In this strategy, the SA chains are co-cross-linked by CaCl2 and cationic octa-ammonium polyhedral oligomeric silsesquioxane (Oa-POSS) particles as the first network, and an organically cross-linked poly(N-isopropyl acrylamide) (PNIPA) network is introduced into the gels as the second network. Several main results are obtained from the synthesis and characterization of the gels. For OP-PN gels, their properties depend on the content of both uniformly dispersed Oa-POSS and PNIPA network directly. The increased Oa-POSS and PNIPA network content significantly improves both the strength and resilience of gels. Relatively, the increased Oa-POSS is greatly beneficial to the modulus of gels, and the increased PNIPA network is more favorable to advancing the tensile deformation of gels. The gels with hydrophilic PNIPA network exhibit better swelling ability and remarkable temperature responsiveness, and their volume phase transition temperature can be adjusted by altering the content of Oa-POSS. The deswelling rate of gels increases gradually with the increase of POSS content due to the hydrophobic Si–O skeleton of POSS. Moreover, the enhanced drug loading and sustained release ability of the target drug bovine serum albumin displays great potential for this hybrid gel in the biomedical field.In order to improve the performance of traditional sodium alginate (SA) hydrogels cross-linked by Ca The corner arms are reactive or inertial functional groups, which endow POSS with diversified functionality and reactivity [To further improve the mechanical properties and introduce stimulus responsiveness into SA gels, in this work, new nanocomposite SA hydrogels with an interpenetrating polymer network (IPN) structure were designed. Considering that the Caactivity ,26,27. Aactivity . Poly, X-ray diffraction (XRD), differential scanning calorimetry (DSC), thermal gravimetric analysis (TGA), scanning electron microscopy (SEM), and optical microscopy (OM), and the properties of gels—including mechanical properties, swelling, and deswelling behavior—were measured. Moreover, to determine its potential in drug release, bovine serum albumin (BSA) was used as the target drug to analyze the loading and releasing ability of the gels.Based on the above strategy, novel hydrogels were fabricated by combining two different networks: the first one is the SA co-cross-linked by CaClw/w) and dried under vacuum at 40 °C. Sodium alginate (SA) and calcium chloride and were purchased from Aladdin Co., Shanghai, China, and used without further purification. The viscosity of SA  is 400 ± 50 mPa.s. Oa-POSS was provided by Hybrid Plastics Co., Irvine, California, USA. BSA was purchased from J&K Chemical Co., Shanghai, China.NIPA monomer, potassium peroxodisulfate (KPS), N,N’-methylenebisacrylamide (BIS), and N, N, N, N-tetramethylethylenediamine (TEMED) were provided by TCI Co., Tokyo, Japan. NIPA was purified by recrystallization from a toluene/n-hexane mixture  were prepared by a two-step reaction, and the process of synthesis was as follows: A given amount of sodium alginate, KPS, and TEMED was mixed with deionized water in a flask and stirred by a magnetic stirrer for 1 h at room temperature to get a homogeneous solution, then a mixed aqueous solution with monomer NIPA and cross-linker BIS was added to the sodium alginate solution. The solution was stirred quickly for 2 min and then transferred to a mold with certain shape and sealed. Free-radical polymerization was carried out at 20 °C for 24 h to form the first network gels. In the gels, the concentration of sodium alginate was fixed at 2%; the mass ratio of water, NIPA, initiator KPS, and catalyzer TEMED was 1000:100:1.02:0.755; and the molar ratio of BIS and NIPA was fixed at 4%. Then, the formed gels were immersed into supersonic 3 wt % CaCl2 and Oa-POSS for a simple expression, and m corresponds to the mole ratio of NIPA to a single sodium alginate molecule. For example, OP3-PN3 gel means that the mass of Oa-POSS in aqueous solution is 12% of all CaCl2 and Oa-POSS mass, the mole ratio of NIPA is 3 times that of SA. In this research, n and m are equal to or less than 5 to guarantee the homogeneity of gels.In this research, the resulting prepared gels are expressed as OPn-PNm gels, using a simplified numerical value of Oa-POSS content and the ratio of both networks. For OPn-PNm gels, n is defined as 1/4 × mass percentage of Oa-POSS in total CaClFTIR spectra of the gels were taken under ambient conditions by a Nicolet 380 FT-IR spectrometer  with milled, dried, unpurified hydrogels by the conventional KBr disk tablet method.XRD patterns were conducted on a D8 advance X-ray diffractometer  using Cu Kα radiation at 40 kV. The diffraction data were collected with a 2θ angle in the range of 2° to 60° at a scanning rate of 5/min.TGA was analyzed by a Q50 thermogravimetric analyzer  at a heating rate of 20 °C/min in the range of 20 °C to 600 °C under a nitrogen atmosphere, with a flow rate of nitrogen of 30 mL/min.DSC was used to determine the volume phase transition temperature (VPTT) of the samples by using a Q20-Series differential scanning calorimeter . All samples used in DSC measurement were immersed in deionized water at room temperature and allowed to swell for at least 72 h to reach the equilibrium state. The calorimetric analysis was performed from 20 °C to 60 °C at a heating rate of 1 °C/min under a dry nitrogen atmosphere, and the flow rate of nitrogen was 20 mL/min.The morphology of the gels’ network structure was observed by a S3000-N low-vacuum scanning electron microscope . Each sample for observation was rapidly frozen and subsequently freeze-dried for 48 h under vacuum at −60 °C. The dispersion of Oa-POSS in the gels was also observed by SEM, and the samples for observation were etched by 25 wt % hydrofluoric acid (HF) solution to dissolve and eliminate the inorganic particles and then dried under vacuum at 30 °C. The surface morphology of gels was observed by a LV100POL/50iPOL polarizing microscope .2 was used to calculate the tensile strength and modulus, and the tensile strain was taken as the length change relative to the initial length of the sample. The tensile modulus was calculated from the increase in load detected between elongation of 10% and 45%. Compression tests were carried out using samples of the same size, 10 × 10 × 10 mm (width × thickness × length), on the UTM6000 universal mechanical tester . The compression property of all gels was obtained under the following conditions: compression speed 5 mm/min and compression distance 8 mm (80% strain). All gels for testing maintained the same water/polymer ratio (8/1 (w/w)).Tensile mechanical measurements were performed on gels of the same size, 10 × 3 × 80 mm (width × thickness × length), using a UTM6000 universal mechanical tester . The sample length between the jaws was 35 mm and the crosshead speed was 10 mm/min. An initial cross-section of 20 mmThe rheological tests were carried out on a stress-controlled AR2000 rheometer  in dynamic mode at 20 °C. The linear viscoelasticity region was confirmed by dynamic strain sweeps at a constant frequency of 1 rad/s. The storage modulus G’ and loss modulus G” were characterized by dynamic frequency sweeps from 0.1 to 200 rad/s, conducted in fixed strain γ = 1%, which is within the linear regime confirmed by dynamic strain sweeps.The swelling experiment was performed by immersing the dried gels in water at 20 °C for at least 48 h to reach equilibrium. The weight of the gel was measured after wiping off the excess water on the surface with moistened filter paper. The swelling ratio was calculated from the equationThe deswelling kinetics of the hydrogels after a temperature jump from the equilibrated swollen state at 20 °C to hot water at 50 °C were measured after wiping off the excess water on the surface with moistened filter paper. The water retention corresponding to the deswelling ratio was calculated from the equation2 and Oa-POSS aqueous solution), BSA concentration was measured by UV spectroscopy , and absorbance was monitored at 280 nm [Synthesis of hydrogel–drug conjugate was carried out. In the first step of synthesis, BSA was added to sodium alginate aqueous solution to form a homogeneous solution to achieve imbedding. Aside from this step, the process was consistent with the synthesis of blank gels. The loading percentage of BSA was tested by a difference value between added mass and dissolving mass of BSA in reaction condition  could form the ionotropic physical gel rapidly by ion exchange. To structure IPN hydrogels based on SA, NIPA was chosen to be cross-linked first to form a precursor gel with SA, and then the SA network was formed inside the precursor gel by immersing the gel into the solution with abundant exchangeable ions. Polymerization yields, evaluated from the weights of dried gels, were nearly 100% in all cases, revealing a complete reaction. Our concern here is the successful introduction of POSS particles and their link type inside the gels, and several characterizations were used to analyze this problem. First, from the appearance of gels a, it couMoreover, when adding Oa-POSS aqueous solution to the SA aqueous solution as the single cross-linker, the viscosity of the solution increases quickly, accompanied by a great amount of white flocculates, and the integral forming of gels is unsuccessful, meaning that the Oa-POSS particles could not be used as the single cross-linker to achieve the preparation of SA gels. However, this phenomenon indicates that the ion exchange between Oa-POSS and SA happens in the system. According to the molecular structural formula of Oa-POSS, there are eight arms with monovalent ions in the corner of the Si–O cage; a high concentration of Oa-POSS should bring about an increased charge density, which makes it easier to cause aggregation of SA around the POSS particles instead of uniform cross-linking.−1 corresponding to the stretching vibration of (NH3+), 1624; 1501 cm−1 corresponding to the bending vibration of (N–H); and 1139 cm−1 corresponding to the stretching vibration of (Si–O–Si) could be observed. This feature proves the existence of Oa-POSS inside the gels [the gels .Moreover, as shown in the X-ray profiles of Oa-POSS, pure SA, OP0-PN3, and OP3-PN3 gels in 2, the gels cross-linked by POSS particles had a higher ratio of solid residue . Though the actual situation is complex, the combination type (as cross-linker or pure additive) and the cross-linking degree (1 mol Oa-POSS cross-links 1–8 mol SA) are hard to define, and the increased residue mass could still prove the successful introduction of Oa-POSS particles.Thermogravimetric analysis was also used for the gels. Two groups of TG curves belonging to SA and IPN gels with or without Oa-POSS were compared. As shown in Although pure SA hydrogel is not easy to break under compression and small deformation, its strength and resilience still have room to advance in order to meet application demands. The tensile curves of different OPn-PNm gels are shown in From the specific data shown in On the other hand, introducing Oa-POSS truly improves the strength and modulus of both pure SA gels and IPN gels, especially IPN gels. The modulus of OP5-PN3 gels is advanced almost three times that of OP0-PN3 gels. This is ascribed to the overlapped effect of tighter network structure and better stress dispersion by nanoparticles. However, a mass of Oa-POSS should decrease elongation at breakage of gels; the dispersed POSS particles acting as stress concentration points in the gel network lead to increased heterogeneity of the gel, which brings about earlier heterogeneous fracture.The compression properties of pure SA gels and OPn-PNm gels were measured by using a uniaxial compression test. As shown in 3–104 Pa, indicating elastic solid behavior. Second, G’ increased gradually with the increase of frequency for both SA and OPn-PNm gels, indicating that elasticity increases with increased frequency, while G”, corresponding to the viscidity of the network, was stable under low frequency and increased at high frequency. Third, the IPN structure and increased Oa-POSS content led to higher G’, revealing higher strength and better elasticity, which is consistent with the results of tensile tests. The same was found for the G” evolution of gels, meaning greater network viscidity caused by IPN structure and POSS co-cross-linking. Finally, the evolution of the damping factor (tan(δ)) for all gels with shear frequency is shown in The structural characteristics of different gels were further confirmed by rheology tests, and several rheological features are shown in After introducing the hydrophilic PNIPA network, the swelling ability of gels underwent a remarkable change, and at the same time temperature responsiveness was also brought into the gels. Moreover, according to the swelling characteristics, all gels had a volume phase transition temperature (VPTT) corresponding to the drastic decrease of swelling ratio with increased temperature. Although the lower critical solution temperature (LCST) of PNIPA macromolecule chains is unique, the OPn-PNm gels showed differential VPTT due to the interaction between both networks. Thermoanalysis was used to display the VPTT of gels more directly. The addition of the PNIPA network endows the gels with responsiveness. The response rate of gels, as one of the most important factors that must be considered for the application of thermosensitive hydrogels in many fields, was analyzed by testing the deswelling kinetics.Relatively, the addition of Oa-POSS increases the deswelling rate of gels significantly. OP5-PN5 gels exhibit fast transparency change as a sign of phase transformation b; they cwas simulated, as shown in Based on the results obtained from comprehensive structure and performance characterization, the structure of the POSS hybrid IPN hydrogels In order to determine the application potential of these kinds of gels, a common drug-delivery macromolecule, bovine serum albumin (BSA), was used as a target to test drug loading and sustained release ability. The profiles of drug release for SA gels and OPn-PNm gels are shown in It needs to be pointed out that the drug loading and release exploration here is only one specific example to display the potential of this gel as a drug-release system. As we know, different drugs with special molecular structure would have different interactions with the gel matrix, which would to be analyzed individually. For the OPn-PNm gels, the introduction of IPN structure and Oa-POSS could adjust the hydrophilic–hydrophobic character of the gels and improve their ability to be combined with certain drugs. On the other hand, the temperature responsiveness of this gel could also be applied for drug delivery in vitro. Correlative experiments were carried out in a simulated human body environment by using the micromolecule drug flutamide as the target drug. It was found that, compared to pure PNIPA gels, OPn-PNm gels had better drug loading and sustained release ability.2 as the co-cross-linking agent of SA and introducing a temperature-responsive PNIPA network into the SA hydrogels simultaneously, to obtain a series of transparent and homogeneous gels without obvious phase separation or aggregates. Through comprehensive analysis of the gels by FTIR, X-ray, TGA, DSC, SEM, and property characterization, it could be confirmed that the Oa-POSS was introduced into the gels successfully, and its content in the gels was determined by the concentration of POSS in a reaction in aqueous solution. Moreover, the addition of a second PNIPA network and Oa-POSS had a significant effect on the properties of gels, and several main conclusions are obtained.In this work, to develop novel biomass-based stimulus-responsive hydrogels with excellent properties, double network POSS hybrid hydrogels (named OPn-PNm gels) were synthesized by using Oa-POSS cationic particles to partly substitute CaClFirst, the mechanical properties of OPn-PNm gels showed great change, which depended on the content of Oa-POSS and PNIPA network inside the gels. With the increase of PNIPA content, the strength and elongation at breakage of gels increased considerably, while the modulus was affected slightly. This is attributed to the stress loading mode of both networks: the rigid SA network as the main stress loader determines the modulus in initial deformation, the second PNIPA network helps to share more stress and keep the gels unbroken in bigger deformation. The increased Oa-POSS improved the strength and modulus of gels significantly, while the elongation at breakage of gels exhibited a considerable decrease. This is ascribed to the stress concentration caused by the increased heterogeneity of gels due to microaggregation of Oa-POSS particles. In addition, the compression resistance and resilience of gels were improved significantly by adding the second network and Oa-POSS, revealing that the network became stiffer. This network characteristic could also be proved by the rheological measurement results. Under the same frequency region, with the increase of the second PNIPA network and Oa-POSS content, the storage modulus and loss modulus of gels increased at different levels, indicating a more elastic network and stronger viscous behavior. Also, the damping effect of OPn-PNm gels was enhanced with the increased PNIPA network content. There was a stronger interface between the two polymer networks, resulting in greater energy consumption.Second, through the research related to the swelling and deswelling properties of gels, it was found that the PNIPA network improved the swelling ability of gels significantly due to its hydrophilic nature, while Oa-POSS had an inverse effect due to the increased hydrophobicity, which could be supported by the results of water contact angle tests. The temperature responsiveness became obvious with the increase of PNIPA content. The VPTT of OPn-PNm gels was close to that of PNIPA gels and should shift to lower temperature with the increase of Oa-POSS content. However, the complete shrinking of OPn-PNm gels at high temperature was inhibited by the robust and hydrophilic SA network. Moreover, the OPn-PNm gels exhibited good swelling–deswelling repeatability under low–high temperature circulation due to the resilience of the gel network.Third, the deswelling rate of OPn-PNm gels increased with the increased PNIPA and Oa-POSS content, the PNIPA network was the main driving force causing the shrinking of the network, and the Si–O skeleton of Oa-POSS acted as a hydrophobic core to accelerate the shrinking of polymer chains. Moreover, the introduction of Oa-POSS particles created some small pores inside the gel network, and the inhomogeneous shrinkage around POSS also formed small pores in the gel surface, all of which improved the deswellling rate.Finally, to investigate the potential of these hybrid gels as a drug-release system, BSA was used as a target drug to analyze the drug-loading and -release properties of the OPn-PNm gels. As the results showed, the addition of PNIPA network and Oa-POSS particles could improve the drug-loading ability effectively due to their strong interaction with drug macromolecules. Although the burst release of drug still existed for all gels, the increased Oa-POSS content significantly improved the sustained release effect of gels in both water and Tris-HCl buffer solution.


P-H1 and M-H1 were synthesized, and they could form 1:1 stable complexes with 4-[-styryl]-N-methylpyridinium iodide (G) in water. Compared with G, the host-guest complexes exhibited enhanced fluorescence, which might be attributed to the spatial confinement of G and restriction of aggregation-caused quenching (ACQ) effects. Based on the host-guest complexation, the first helic[6]arene-based chiral assemblies were then constructed, and they showed rectangular or hexagonal nanostructures by scanning electron microscopy (SEM) images. Interestingly, the assemblies showed clear mirror-image circular dichroism (CD) and circularly polarized luminescence (CPL) spectra in aqueous solution, revealing a consecutive chirality transfer from the chiral macrocyclic cavities of the hosts to G. Moreover, the supramolecular chirality of the assemblies could also show responsiveness to the pH values and temperatures of the system.A couple of water-soluble chiral 2,6-helic[6]arene derivatives  Circularly polarized luminescent (CPL) materials have aroused extensively interest for their potential applications in the fields of biological probes styryl]-N-methylpyridinium iodide (G) in water  effects. Based on the host-guest complexation, the first helic[6]arene-based chiral assemblies with rectangular or hexagonal nanostructures were then constructed. Interestingly, the supramolecular assemblies showed clear mirror-image CD and CPL spectra in aqueous solution, revealing a consecutive chirality transfer from the chiral macrocyclic cavities to G. Moreover, the assemblies could also show the pH and temperature responsive CD and CPL properties.Recently, we reported a new type of chiral macrocyclic arenes, 2,6-helic[6]arenes . As shown in P-H1 was added into a solution of G, significant chemical shift changes of the protons on P-H1 and G appeared. It was found that protons H1, H2, H3, and H4 of the guest shifted upfield dramatically by 0.47, 1.02, 0.50, and 0.48 ppm, respectively. While the resonance peaks related to protons H7, H8, H10 showed downfield shifts compared with free guest G . Moreover, the signals of protons Ha, Hb, Hc, and Hd on P-H1 also showed upfield shifts due to the host-guest interaction. These observations suggested that host P-H1 could form 1:1 stable complex with guest G, and the complexation between P-H1 and G was a fast exchange process on the NMR spectroscopic timescale. From the 2D ROESY spectrum of a solution of 2.0 mM P-H1 and 2.0 mM G  mass spectra confirmed the formation of the 1:1 complex between P-H1 and G  experiments were then carried out in aqueous solution (Ka) for 1:1 complex P-H1·G was determined to be (3.84 ± 0.24) × 105 M−1. Similarly, M-H1 could also form 1:1 stable complex with guest G in water, and the Ka value for the 1:1 complex M-H1·G was determined to be (3.21 ± 0.23) × 105 M−1.Enantiomers 2.0 mM G , S11, coH1 and G , S15 as solution . Consequ−5 M G in aqueous solution exhibited an absorption maximum at 450 nm and a weak emission band at about 600 nm, respectively. When equimolar P-H1 was added into the solution of G, distinct bathochromic shifts of absorption maximum occurred from 450 to 475 nm, while a new emission band centered at 618 nm appeared. Probably due to the cavity inclusion and rotation restriction of G, the ACQ effects of G were avoided and an intensive emission signal was observed in the aqueous solution of P-H1·G.UV/Vis and fluorescence experiments were also performed to investigate the host-guest complexation. As shown in P-H1 contained six carboxyl groups, we further explored the acid/base controlled complexation of P-H1·G by 1H NMR spectroscopy. As shown in P-H1·G in D2O, the carboxylate groups in P-H1 were acidified into carboxylic acids, and the protonated host was then precipitated from the solution. Although the guest was also protonated and possessed good water solubility, most of them might be absorbed by the P-H1 sediment, leading to no signals in the spectrum. Followed by adding an excess of NaOD aqueous solution to the above system, the protonated host dissolved in the solution, and the proton signals of complex P-H1·G recovered, which suggested that complex P-H1·G formed again. These results indicated that the acid/base stimuli-responsive complexation between P-H1 and G could be efficiently controlled  was rapidly injected into 9 mL of water/THF 2:1 (v/v) solution under ultrasonic condition. After the ultrasound was sustained for 5 min, the solution was bubbled by Ar for about 1 h to remove the THF. Then, by continual bubbling, the obtained solution was heated to 100°C until 5 mL of water remained. Thus, the uniformly distributed self-assemblies in H2O were obtained with 0.1 and 0.6 mM, respectively. To study the topological influence of P-H1 and G on the self-assemblies, the similar assembled experiments for free P-H1 and free G were also carried out, respectively. Scanning electron microscopy (SEM) and dynamic light scattering (DLS) were used to investigate the assembled structures of P-H1·G. SEM images of the assembled P-H1·G (0.6 mM) showed hexagon nanostructures with diameters of about 160 nm  decreased to 3.00, the self-assembly morphology of P-H1·G changed from nanohexagon to irregular structures  also showed a pair of mirror-image CPL signals ranging from 500 to 850 nm, which might be attributed to the chirality transfer from the macrocycles to guest G by the strong host-guest interactions and the well-ordered assembled nanostructures. Correspondingly, the maximum glum values of CPL for P-H1·G and M-H1·G were determined to be −2.67 × 10−4 and 1.48 × 10−4 at 655 nm, respectively. Moreover, the pH values dependent on CPL signal changes of the assembled solution could also be found. As shown in P-H1·G/M-H1·G by acid, and the weakened host-guest interactions by base, which were further proved by FL spectra and photograph showing color changes styryl]-N-methylpyridinium iodide in water. Compared with the guest, the host-guest complexes exhibited enhanced fluorescence, which might be attributed to the spatial confinement of the guest and restriction of ACQ effects. Based on the host-guest complexation, the first helic[6]arene-based chiral assemblies were then constructed, and they showed rectangular or hexagonal nanostructures by SEM images. Interestingly, it was found that the assemblies showed clear mirror-image CD and CPL spectra in aqueous solution, which revealed a consecutive chirality transfer from the chiral macrocycles to the achiral guest. Moreover, the assemblies could also show the responsive CD and CPL activities to the pH and temperatures, which would provide an opportunity to further construct new chiral functional materials.In summary, we have synthesized a couple of water-soluble chiral 2,6-helic[6]arene derivatives All datasets generated for this study are included in the manuscript/This work was done mainly by YG, and the manuscript was written by YG with the guidance of YH and C-FC.The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest. The handling editor declared a shared affiliation, though no other collaboration, with the authors  at time of review.


Thus, reduction in the volume of concrete consumption is essential to control greenhouse gases. One approach to this problem is to use textile reinforced concrete (TRC). The main aim of the present study was to compare the subtle TRC facade made of three different types of technical textile rovings  with ordinary facades reinforced by steel reinforcement (ORC). The goal was to compare the basic environmental impact potential according to product category rules (PCR) for concrete structures. The functional unit was defined as an experimental facade with an area of 60 m2 and a 100-year lifespan. Inventory data were elaborated for concrete, steel, and textile fiber production; the building site; service life; demolition; and final disposal. The main life cycle assessment (LCA) parameters were global warming potential (GWP), ozone depletion (ODP), acidification (AP), eutrophication (EP), abiotic depletion (ADP), and photochemical oxidant creation (POCP). All the data used in the work were related to Czech Republic. Textile reinforced concrete facades appeared to be more environmentally friendly in four of six impact categories by an average of 30%. The results of the present study revealed that, in comparison to ORC, TRC has a lower environmental impact for the given conditions and thus good potential for use in sustainable construction.Pitch-faced concrete is becoming a very popular element of modern architecture in the 21st century. In particular, the demand for concrete facades is increasing globally. On the other hand, climate change, environmental degradation, and limited resources are motivations for sustainable building materials. The construction industry is one the highest emitters of CO Civil engineering is one of the largest global consumers of material resources, and producers of waste and harmful emissions. Buildings and building structures have a significant impact on the environment at a local scale as well as globally ,2. This Environmental impacts can be divided into several levels: global, regional, and local . Issues 2 emissions, is cement production [2 emissions [2 emissions in the EU [It is widely known that concrete is the second most-used material in the world after water ,9. Accoroduction . The glomissions , which hmissions  and furtmissions . The Eurmissions . Construn the EU . Optimizn the EU ,19.There are several approaches to solve the above-mentioned problems. Clearly, one possibility is to replace concrete with completely different materials, but this is not possible in many cases due to the indisputable advantages of reinforced concrete. Partial substitution of some environmentally demanding concrete components appears to be an interesting solution ,21, as wThe main aim of the present study was to compare the subtle TRC facade elements made of three different types of technical textile rovings  with ordinary facades reinforced by steel reinforcement (ORC) in terms of selected basic environmental impact potential. Production in the Czech Republic and Czech climatic conditions were considered for all variants. The analysis includes all distances for the transport of the individual raw materials and materials needed for production, as well as the energy flows for the specific production.The details of mixtures of high-performance concrete (HPC) and conventional concrete of class C30/37 (OC) used for all types textile reinforced façade panels are described in 3 density, 15 MPa tensile strength and 2 GPa modulus of elasticity. For OC reinforcement, 6-mm steel curry mesh was used.For textile reinforced concrete elements, hand-made textiles from commercially available AR glass, basalt, and carbon rovings were used, and the technical properties of glass rovings are noted in V1 (ORC steel): Standard concrete reinforced with a 6 mm diameter steel curry net with a mesh of 150 mm × 150 mm. Total thickness of facade boards is 60 mm see .V2 (TRC glass): High performance concrete reinforced with 2 layers of AR glass textile reinforcement. Total thickness of facade panels is 18 mm see .V3 (TRC carbon): High performance concrete reinforced with 2 layers of carbon textile reinforcement. Total thickness of facade panels is 18 mm.V4 : High performance concrete reinforced with 2 layers of basalt textile reinforcement. Total thickness of facade panels is 18 mm.A total of four variants of concrete facade panels were compared:Cradle-to-grave comparisons of the environmental impacts of concrete facades were carried out according to the ISO 14040:2006 standard , which d2 and 100-year lifespan was set as the functional unit. The concrete facade serves as a design feature, as well as a durable building envelope. It protects the building from adverse effects for as long as possible while maintaining design and mechanical parameters. The functional unit represents a measure of the function of the studied system. It provides the basis for the modelling that follows. For the comparison, an experimental facade with area of 60 mFor the comparison of facade panels, a cradle-to-grave scale was used. Therefore, all life phases of the individual variants were assessed as follows: extraction of raw materials and transport to the production plant; production of partial materials and transport to the prefabricated production plant; production, treatment, and transport to the building; installation; and use to the end of the life cycle. Some data used for modelling were obtained from cement manufacturers in the Czech Republic. However, because production is similar worldwide, these values can be considered as universally representative. The transport of individual components was calculated for production and prefabricated production plants in the Czech Republic, and these data may vary considerably for other countries. Concrete facade life cycle steps were broken down into three phases: production, use, and end of life.The production phase includes all processes from the extraction of raw materials, their transport to production plants, processing, transport to the place of production of prefabricated elements, production of prefabricated parts, treatment, storage, transport to the construction site, and their installation. For each material, the exact distance of the conveyed element from the production site to the prefabricated production plant was calculated. Subsequently, the transport of precast elements to the building site was evaluated. Transport was divided into long-distance and local. For local transport, a distance of up to 30 km was considered, and the considered vehicle was a small truck . For long-distance transport, a bigger truck was considered . Data on concrete mixing and preparation of the prefabricated panels were set as averages of Czech concrete plants taken from ICFconcrete 3.0 . Data onAlthough the lifetime of TRC panels is several times higher than that of conventional panels, it is necessary to take into account the moral lifetime, which may be decisive in the case of facade panels. For this reason, a service life of 100 years was chosen for all variants. For TRC elements, regular repairs and a possible replacement of 5% of the elements are expected during this time. In the case of conventional panels, repairs and replacement of elements in the order of 15% are expected. During the use phase, maintenance and cleaning with pressurized water was counted once every 10 years of the facade life. In addition, water for facade cleaning was estimated according to the experience of local companies.In the final phase of the life cycle, work related to demolition is included, including the use of a crane and transport to a landfill. The recyclability of a particular type of reinforced concrete is not included in the assessment.The following tables summarize the input data used to calculate environmental impacts. XY is the result of the impact category indicator XY, CFi,XY is the characterization factor for substance i and impact category XY, mi is the amount of elementary flow of the substance I, I represents elementary flows, and r represents emission sources.In the environmental impact assessment phase, the individual results of the inventory analysis are linked to specific environmental impact categories, and their influence for each category is expressed with an impact category indicator. The first step in impact assessment is classification. Elementary flows from inventory results are assigned to each impact category, which can be potentially influenced by them. Then, in the next step, which is called characterization, the measure of the effect of an elementary flow on individual impact categories is calculated according to its characterization model. Such a model is a defined procedure that expresses the influence of an elementary flow on individual impact categories using a characterization factor for each flow. After classification and characterization of each flow, the result of the impact category indicator can be calculated as the summary of the results of the impact category indicators of all pollutants from the formula :(1)VXY= The LCI output data essential for LCA studies of four variants of facade panels were divided into non-renewable energy resources, non-renewable resources, and renewable resources. 2, and V4 has the lowest GWP. Similarly, AP, EP, and POCP were highest for V1 and lowest for V4 on aggregated environmental impacts at all life cycles. ADP was highest for V2 and least for V4.The aggregated potential of each variant on the different environmental impacts during the all life cycle is shown in 2 in comparison to steel production. In the V3 variant, epoxy resins and super-plasticizer added more GWP to TRC production, while in ORC it was negligible. Transportation contributed more GWP to ORC due to its higher weight compared to TRC. The global warming potential (GWP) is among the most important factors for LCA of concrete development. However, the results may vary depending on the location of the production of prefabricated elements and on the sources used, and therefore cannot be completely generalized. Nonetheless, the results show the potential for improving environmental impact by using TRC for subtle structural elements.The calculation included detailed production data, transport data of individual elements, and partly, their service life. If we consider only the absolute life of the elements and neglect the moral life, the advantage of TRC elements would multiply, since the TRC elements have a lifespan of several hundred years. Durability is undoubtedly an advantage of this material and plays a major role in the results; however, the environmental advantage is already visible for the production phase. The indisputable advantage is, of course, in the lower weight of the final elements and in the steel replacement, which is reflected in the transport and assembly. However, it should be noted that the presented types of textile concrete have some reserves and the environmental impacts could be further improved. Using HPC/UHPC leads to a lifetime that is unlikely to be used in real conditions. We assume that the elements will be replaced for aesthetic reasons before the material disintegrates. The environmental impacts could be improved at two other levels: the use of more environmentally friendly materials and the recycling of TRC. Cement and superplasticizer play a major role in the textile concrete facade. An interesting topic to explore would therefore be the partial replacement of cement with other materials, as well as a change in the plasticizer, with a detailed comparison in terms of durability and life cycle assessment.The present study aimed to compare the subtle TRC facade elements made of three different types of technical textile rovings  with ordinary facades reinforced by steel reinforcement (ORC) in terms of selected basic environmental impact potentials using an LCA technique that also included a life cycle data inventory. In conclusion, after a detailed calculation and analysis of the whole life cycle, textile reinforced concrete facades appear to be more environmentally friendly in comparison to the ordinary solution in four impact categories by an average of 30%. Ozone depletion (ODP) shows an increase due to the use of plasticizers based on polycarboxylates, which have a great influence on this potential. Carbon has higher results from all compared TRC solutions because of the demanding production process. Carbon fiber production has the greatest effect on abiotic depletion, which is twice as high as that of the ORC solution. The remaining impact categories show very good results for TRC. In general, TRC proves to have very good potential for sustainable construction and environmental impacts for the given conditions and not only for facades. Its use can be applied to similar subtle non-bearing elements. A topic of further research could be its use for load-bearing elements. However, this is subject to further examination and implementation of the relevant standards.


Dowels are located in transverse joints of Jointed Plain Concrete Pavements (JPCP) and they are used to provide load transfer between individual slabs, reduce faulting and improve performance. Dowels and the concrete itself are under the highest stress in the vicinity of joints; thus, in terms of pavement design, the joints are the weakest points of the whole structure. This study dealt with the drawbacks of JPCP with dowels. The evaluation was based on direct measurements on real airport and motorway pavements and highlights insufficient efficiency of load transfer and its possible causes. The authors present a successful outcome with validation by using the finite element method where high tensile stress values of the surrounding concrete were found. Jointed plain concrete pavement is typically composed of a Portland Cement Concrete (PCC) surface course constructed on top of either an underlying base course or in exceptional cases on the subgrade. Joints of concrete pavement are stressed by the effects of overruns of heavy vehicles and temperature and moisture gradient of concrete slabs. The dowels in transverse joints must allow horizontal movement of slabs in the contracting time after the pavement is paved and during its further use. In addition, they reduce vertical movements on slab edges and occurrence of vertical unevenness along the pavement lifecycle. The monitored parameter is the transfer of load on joints expressed by the value of LTE (Load transfer efficiency).ld is the loaded slab and ud is the adjacent unloaded slab deflection [The loaded and adjacent unloaded slabs deflect when a wheel load is applied at a joint edge. Deflections of jointed slab are directly coherent to joint performance. When the loaded and unloaded slabs deflect equally, the joints performance is accomplished. Load transfer efficiency may be described by the following equation:LTE (%)=dThe LTE depends on a number of circumstances, including the base course or subgrade support, aggregate interlock, joint width and spacing, temperature and moisture (which could affect joint opening), number of passes and load intensity, and the methodology of measurement through the load transfer devices . Several studies describe the most performance problems with concrete pavement as a result of poor performance of transverse joints ,3. A pooLong-term evaluation of the measurement results on tested concrete pavements of airport runways and motorways shows that the LTE values range between 0.70 and 0.90. According to the current Czech technical specification TP 92, efficient transfer should exceed 0.90, otherwise the structures should be evaluated to decide whether a measure is necessary. This means that the majority of joints fail to meet this criterion. The evaluation of the current study is based on direct measurements by falling weight deflectometers (FWD) made by companies KUAB and Rodos .The issue of LTE is dealt with by many authors and organizations ,6. The aIn addition, the results show that in many cases LTE is low when different types of dowels are used. The reasons include the behavior of dowels at overruns of heavy vehicles, the quality of subbase and subgrade, and the quality of dowels, their coating and alignment. In Slovakia, recommended dimensions of dowels (diameter and length) are applied to concrete slab thickness; in the Czech Republic, a unified diameter (25 mm) and length (500 mm) of dowels are used for all pavement thicknesses ,16,17,18Some studies and recommendations also suggest that the position of dowels towards the transverse joint significantly affects the performance. The alignment of dowel bars is important since significant misalignment of dowels in a doweled joint may prevent that joint from opening/closing properly. The occurrence of a single joint that does not open/close effectively will not necessarily result in a mid-panel crack or another pavement defect, but the risk of mid-panel cracking and joint distress increases with each successive joint with limited opening/closing capabilities. The vertical tilt is particularly critical, as well as the vertical and longitudinal translation of the dowels .Software based on the principle of the finite element method (FEM), such as SCIA Nexis, ANSYS, etc., allow modeling of stress in concrete pavements, which can be used for making comparisons of calculated and real values. The FEM calculation allows monitoring stress conditions of concrete in terms of load and to compare different types of structures and used dowels . 3D FEM is an efficient and accurate method to calculate the interaction characteristics in concrete pavements. Research activities tend to study tensile stress concentration of the surrounding concrete around dowels and potential to cracking. A small diameter, high strength of dowels and their position are considered the main reasons for failure ,25,26,27The aim of the research activities of the authors from the Czech Republic and Slovakia was to carry out measurements on test sections, present the experience with modeling in software based on the principle of FEM and inform of new findings regarding dowels. In addition, we aimed to point out and investigate the differences in tensile stress on the bottom part of concrete slabs and around dowels with defectively installed dowels, which are crucial for design ,29.The aim of the measurements was to evaluate bearing capacity and determine LTE of concrete slabs on airport runways (RWY), taxiways (TWY) and aprons in Slovakia, and road sections complying with motorway design standards in the Czech Republic.An example of a “heavy loaded” area of concrete pavement includes an airport runway. Deformations measured by dynamic load on the slab edge (at the joint) and recorded on the adjacent slab depend mainly on the construction design of joints. The transverse joints were reinforced with dowels while the longitudinal joints were without any reinforcement on a RWY section selected for experimental measurements.Dynamic load tests with the aim to measure LTE between slabs were carried out by FWD KUAB  with the average load force of 150 kN and with the load duration of 60 ms. According to the differences in the pavement structure—mainly in the slab thickness —the runways were divided into sections. A configuration scheme of five tested slabs is shown in LTE on transverse joints was higher than 80% and, on some paths of RWY (JPCP thickness 300 mm), it was higher than 92% a. LTE onThe evaluation of LTE on edges of six slabs with the FWD/HWD RODOS 10001  was performed. Low values of load transfer on transverse joints reinforced with dowels (slab thickness 250 mm) were found on two sections on R1 and D1. The effect of different load  and temperature (gradient −0.10 and +0.43 °C/10 mm) were also studied . The meaThe measurement results from the test sections can be used for modeling in software based on the finite element method and can be focused on specific and problematic parts of the structure.The modeling included an analysis of stress on concrete slab edges while using findings from field measurements on the test sections. The software allows modeling of stress at the bottom part of slabs by traffic and temperature load and can account for the interaction of pavement and subgrade.Different degrees of interaction of concrete slabs were considered for the selected pavement structure. The result of such modeling is a numeric and graphic representation of concrete slabs behavior (stress and deflections).The calculation was made by FEM method with the use of SCIA Nexis software. The modeling of the interaction of concrete slabs and subbase is reduced to a 2D model, whose special case is the Pasternak model. Pasternak’s characteristics of subbase properties with two parameters (C1 and C2) describe the behavior of slabs better, particularly on solid subbase. The authors of the software, Kolar and Nemec, produced a multi-parameter 2D model, which is equivalent to half-space. Selecting proper constants of C1 and C2, it is possible to draw close to the real deformation of slabs.zE is the deformation modulus of soil, G is the shear modulus, and H is the depth of deformed zones of the spatial model “damping function” f(z), which is defined by the slump ratio at a given depth w for settlement surface w0 in the form:The constant C parameters influence the stress and the distribution stress has an effect on the settlement of the base (subbase). Therefore, an iterative equation is used for the constant C. For the calculation module Soilin and the relationship between the constants of the model (3D) and surface model (2D) the following equations were used:Unlimited slide is considered between the slabs and the subbase, which helps to get the most unfavorable stress values in the slab. This phenomenon usually occurs in practice, particularly regarding the dilation of slabs and warping of slabs due to temperature gradient.Another step is the modeling of transverse and longitudinal joints which break the integrity of the pavement. The selected 2D macro can be assigned with a constant thickness (constant isotropy), variable thickness (variable isotropy) and orthotropy. In the cases when the constant isotropy is assigned, 2D macros will be assigned with a constant thickness and material . In the case orthotropy is considered, macros will be assigned with thickness parameters using the values of stiffness matrix elements. This is method allows modeling any joint.The calculation included an analysis of static stress at the bottom part of the concrete slab while considering defective positions of dowels. Software ANSYS, with the use of detail spatial calculation models, modeled pavement structure, which consisted of a mechanically compacted aggregate layer with the thickness of 250 mm and concrete slabs fitted with dowels and tie bars. Tie bars are made of construction steel of 20 mm diameter and 800 mm length, and their central part is covered with a plastic coating. Steel dowels, 25 mm diameter and 500 mm length, are smooth on the surface. The sliding of dowels is allowed by the plastic coating of an average width of 0.4 mm. The global calculation model covers an area formed by 3.0 m × 3.0 m slabs. The detailed, more accurate, model includes a transverse joint with five dowels. The global calculation model includes boundary conditions for the detailed model, global displacement and stress of the area. The cross cut of the concrete slab at the place of transverse and longitudinal joints is considered based on the assumption that at these weaker spots the slabs will be split into separate rectangular segments of 5.5 m × 4.5 m. The thickness of concrete slabs is 240 mm, which is a similar value as the standard used thickness of concrete slabs in the Czech Republic . The dowThe calculation used a boundary condition of the fixed placement in the horizontal direction and flexible placement (Winkler’s model) in the vertical direction. This boundary condition was applied to the bottom part of the subbase aggregate layer. Winkler’s model of subgrade works with modeling of subgrade soil. Linear changes in temperature along the concrete slab thickness were assigned in such way that the temperature of the bottom was 0 °C and the surface −7 °C. The external load by dual wheel axle of 50 kN force, representing load by the standard design axle (Czech design axle), was entered into the numeric model apart from its own weight and temperature load. The axis of one wheel axle intersects the axis of a dowel. The axis of the second wheel axle is located 344 mm apart in the Y direction. The diameter of the contact areas is 240 mm. These areas are located right next to the transverse joint edge of the monitored slab .Global numeric model ZS1 ;Global numeric model ZS2 (load by axle);Local numeric model ZS1 ; andLocal numeric model ZS2 (load by axle).Spatial models of the pavement allow performing different variants of solutions with the inclusion of dowels in different positions. Non-linear calculations were performed for 17 variants. A certain variant models the precise position of a dowel according to the project design. Another variant models the missing dowel. Six variants model different vertical translations of dowels. Another six variants model different vertical tilts of dowels. Three variants model different longitudinal translations of dowels. Each of the variants of defective dowels was described by a calculation:The goal of the calculation was to observe whether a defective dowel position has an impact on the stress at the bottom part of concrete slab and cracking potential of concrete in the vicinity of the dowel. An analysis of stress of the concrete around dowels was performed as well. The mentioned assumptions were applied for the calculation of a set of six slabs. The pavement structure consisted of a concrete layer of 250 mm thickness, laid on a layer of asphalt concrete AC of 50 mm thickness, a cement bound granular mixture CBGM of 180 mm thickness, and a protection gravel course of 270 mm thickness. The scheme of the set of concrete slabs is shown in The calculations of LTE show the impact of load transfer values on the evaluated parameters. In the first case, orthotropy was considered for the evaluated transverse joint without reduced stiffness matrix elements a. In thiIn another case, when orthotropy was considered for the evaluated transverse joint, but with reduced stiffness matrix elements, the values of parameters of subbase C1 and C2 near the evaluated transverse joint were reduced as well b. The reIn addition, a situation was modeled when the parameters of the transverse joint were reduced in greater degree and some of the parameters had zero value. As in the previous case, the values of parameters of subbase C1 and C2 near the evaluated transverse joint were reduced, the values equaled zero under the joint c. The caThe adverse effect of temperature gradient on slab stress can be reduced . This caFor the given conditions, the calculations of stress were made on the K EX and K INT structures. Regarding both structures, the length of slabs was 5.0 m and the width was 3.5 m. The stress at the bottom of the slab calculated while taking into account the temperature effect inside (K INT) was lower than when dealing with the pavement outside (K EX). This difference was based on lower temperature gradient and the fact that the structure (K INT) was designed for the central part of the tunnel. In contrast to the point of maximum load-induced stress, the temperature-induced maximum stress was in the center of the slab.The calculation results of horizontal tensile stress at the bottom part of the slab joint under the dowels were only slightly influenced by the investigated misalignment positions of dowels, and they nearly always ranged 0.94–1.05 MPa for slabs of 300 mm thickness and 1.2–1.3 MPa for slabs of 250 mm thickness, which are low values . In addict = 2.3 MPa) , steps (ZS1 and ZS2) and variants. The FEM analysis determined tensile stress of the surrounding concrete for each dowel position (5.5–14 MPa) and initiated a potential risk of cracking (approximated tensile strength of concrete f2.3 MPa) . The couThe lowest values of tensile stress were identified in Variants V10 and V11, when the dowel was tilted towards the load by the axle. The highest value of tensile stress was identified in Variant V14, when the dowel was tilted out of the load by the axle. Therefore, it was possible to see the highest sensitivity of tensile stress to the tilt of the dowel position.ct = 32 MPa)—in accordance with the requirements of standard CSN EN 13877-1. Consequently, concrete cracking will not occur.The calculated extreme values of compressive stress had a similar trend (regarding the variants) to the one of tensile stress. In no variants did compressive stress (11–30 MPa) reach compressive strength of the material  and measurements of deformations on real road pavements structures with the use of strain gauges will support theoretical results. Based on the performed experiments and modeling results, revision of allowed misalignment of the dowels could lead to updates of this standard.The world research of dowels and experience with their application lead to using bigger diameter of dowels in relation to JPCP thickness and number of load applications. Therefore, the research results were applied in the revision of standard TP 098 Design of Road Concrete Pavements in Slovakia where 30 mm dowel diameter needs to be used for highways and allows designing and assessment of roads by the finite element method.


Escherichia coli and Pseudomonas aeruginosa, rescues antibiotic efficacy against antibiotic‐exposed cells, and represses biofilm formation. It is shown that cPAC has a potentiating effect, both in vitro and in vivo, on a broad range of antibiotic classes against pathogenic E. coli, Proteus mirabilis, and P. aeruginosa. Evidence that cPAC acts by repressing two antibiotic resistance mechanisms, selective membrane permeability and multidrug efflux pumps, is presented. Failure of cPAC to potentiate antibiotics against efflux pump‐defective mutants demonstrates that efflux interference is essential for potentiation. The use of cPAC to potentiate antibiotics and mitigate the development of resistance could improve treatment outcomes and help combat the growing threat of antibiotic resistance.Antibiotic resistance is spreading at an alarming rate among pathogenic bacteria in both medicine and agriculture. Interfering with the intrinsic resistance mechanisms displayed by pathogenic bacteria has the potential to make antibiotics more effective and decrease the spread of acquired antibiotic resistance. Here, it is demonstrated that cranberry proanthocyanidin (cPAC) prevents the evolution of resistance to tetracycline in  Remarkably, when combined with tetracycline, cPAC was able to completely prevent the evolution of resistance in E. coli and P. aeruginosa. These results suggest that in combination with antibiotic therapy, cPAC has the potential to decrease the spread of antibiotic resistance and prolong the effectiveness of currently available drugs.The global spread of antibiotic resistance is undermining decades of progress in fighting bacterial infections. Due to the overuse of antibiotics in medicine and agriculture, we are on the cusp of returning to a pre‐antibiotic era in which minor infections can once again become deadly. Countering the fall in antibiotic efficacy by improving the effectiveness of currently available antibiotics is therefore an important goal. Antibiotic efficacy is limited by the expression of intrinsic tolerance mechanisms such as production of antibiotic‐tolerant and/or persister cells, or formation of biofilm, and emergence of antibiotic‐resistant pathogens recalcitrant to treatment due to acquired resistance. Here, we report that a purified cranberry proanthocyanidin (cPAC) fraction potentiates the activity of a broad range of antibiotic classes against the opportunistic pathogens Opportunistic pathogens colonize surfaces in healthcare settings, on indwelling medical devices, and on living tissues, leading to infections that must be treated with antibiotics. Two major factors complicate the effectiveness of antibiotic treatments: i) antibiotic‐resistant bacteria and ii) the formation of antibiotic‐tolerant biofilms.Vaccinium macrocarpon L.) fruit and its derivatives have long been anecdotally reported as a natural remedy for urinary tract infections.P. aeruginosa;E. coli and P. aeruginosa, and demonstrate the broad spectrum, antibiotic‐potentiating activity of cPAC against various pathogenic Gram‐negative bacteria, both in vitro and in vivo. We also show that cPAC is able to repress two important intrinsic antibiotic resistance mechanisms: selective membrane permeability and multidrug efflux pump activity.The American cranberry . FigureE. coli CFT073, P. mirabilis HI4320, and P. aeruginosa PA14 using up to 98% less antibiotic than that required in the absence of cPAC. cPAC also potentiated trimethoprim (TMP) and fosfomycin (FOS) activities to inhibit the growth of P. mirabilis HI4320; 81% and 98% less antibiotic were needed, respectively, than in the absence of cPAC. In the case of P. aeruginosa strain PAO1, cPAC enhanced the efficiency of the antibiotics SMX, FOS, NIT, GEN, KAN, and AZT . The fact that cPAC potentiates a given antibiotic against one strain but not another  provides evidence that the effect is specific and that cPAC is not simply inactivating the antibiotic. It is not surprising that the FICI values for the two P. aeruginosa strains were different for some antibiotics as they had different MICantibiotic values.We conducted screening assays with cPAC in combination with several classes of clinically approved antibiotics belonging to the World Health Organization's list of essential medications.P. mirabilis HI4320. In the case of P. aeruginosa PA14, combination of cPAC with co‐trimoxazole decreased the MIC by 32‐fold, which is significantly more effective than the potentiating combinations of cPAC with TMP or SMX alone . The fact that cPAC potentiates antibiotics, but does not act as an antibiotic on its own, suggests that treatment with cPAC is unlikely to create selective pressure for the evolution of resistance.At concentrations required to potentiate antibiotic efficacy, cPAC alone had no detectable growth inhibition activity against all four pathogenic strains . Given the ability of cPAC to potentiate TMP or SMX alone, we investigated the interaction of cPAC with co‐trimoxazole  higher than survival with SMX treatment alone. The median survival time of infected D. melanogaster treated with cPAC alone or SMX alone was 202 and 178 h, respectively  different from the survival of untreated flies infected with P. aeruginosa PA14. The survival of uninfected D. melanogaster was similar to treatment with cPAC or SMX alone , which indicates that cPAC (at 50 µg mL−1) or SMX (at 256 µg mL−1) alone is safe for this animal.Our next goal was to investigate the potential of cPAC to enhance the efficacy of antibiotics against bacterial infections in vivo. To this end, we used the model host ed Figure3A. SurGalleria mellonella) larvae killing model, in which cPAC or SMX was administered alone, or in combination, to larvae infected with a lethal dose of P. aeruginosa PA14. The median survival of infected and untreated larvae was 21 h, but increased to 47 h with the cPAC and SMX combination treatment. This is a significantly  longer survival time than the 36 h median survival time with SMX treatment alone . These results confirm that cPAC potentiates the activity of SMX in vivo, at the tested concentration of 50 µg mL−1 cPAC.To confirm that cPAC is able to potentiate antibiotics in more than one host, we also used the greater wax moth  inhibition of monoculture biofilms, which is consistent with other studies showing that cPAC or cranberry extracts can decrease bacterial adhesion.P < 0.01) inhibitory effect on the development of biofilms in a dose‐dependent manner  as an indicator, which revealed that cPAC increases outer membrane permeability of bacterial cells , remained fluorescent over time due to a failure to pump out EtBr  membrane disruption by cetyl trimethylammonium bromide (CTAB), a cell membrane–disrupting agent, suggesting that outer membrane permeabilization and target specific efflux pump inhibition are achieved by cPAC without altering cell membrane integrity.To identify the mechanism(s) of action by which cPAC potentiates antibiotic activity, we quantified the changes in bacterial cell outer membrane permeability using 1‐ls Figure5A–C. I2.7E. coli, and MexAB–OprM of P. aeruginosa, with the A‐type dimeric cPAC molecule as the test ligand. Ligand‐binding domains of AcrAB–TolC and MexAB–OprM efflux pump components exhibit sufficient space to accommodate the cPAC molecule with an average volume of 497.1 Å3 . We tested structural in silico interactions of cPAC with the exit duct, adapter, and transporter components of the efflux pumps .To understand how cPAC is able to inhibit the activity of efflux pumps, we performed in silico docking analyses using the efflux pump protein complexes AcrAB–TolC of s FigureA and cois FigureA. cPAC sE. coli in vitro , P. mirabilis HI4320,P. aeruginosa PAO1 (ATCC 15692), and P. aeruginosa PA14 (UCBPP‐PA14).P. aeruginosa PA14 were used in this study: −mexL (overexpressing MexJK‐OprM),−nfxB (overexpressing MexCD‐OprJ),−nfxC (overexpressing MexEF‐OprN),−nalC (overexpressing MexAB‐OprM),−mexA (nonfunctioning MexAB‐OprM),−oprM .−1 tryptone, 5 g L−1 yeast extract, and 5 g L−1 NaCl, supplemented with 1.5% (w/v) agar ). After overnight incubation at 37 °C, a single colony was inoculated into 10 mL of Mueller–Hinton broth adjusted with Ca2+ and Mg2+  and the culture was incubated at 37 °C on an orbital shaker at 200 rpm for a time length specific to each experiment. LB broth was used for bacterial culture in all experiments unless otherwise specified. The purified cranberry‐derived proanthocyanidin  was obtained from Ocean Spray Cranberries Inc. The supplier prepared the sample according to well‐established methodsO1 ATCC 192, and PDetermination of MICs: MICs were determined by preparing twofold serial dilutions of cPAC, and antibiotics in MHB‐II broth. A range of concentrations of the antibiotics (0.0003–1024 µg mL−1) was chosen due to their known potency against all four bacterial strains. Bacterial growth was assessed by i) monitoring the cell growth (observed as a pellet and turbidity) in the wells600), and iii) using the resazurin microtiter plate assay.In Vivo Infection Assay Using D. Melanogaster Flies: Fruit flies (D. melanogaster) were infected orally in fly feeding assay in which flies were anesthetized, starved of food and water for several hours, and separated into vials containing filter paper disks inoculated with freshly grown P. aeruginosa PA14, as well as 5% sucrose agar (sterile) with and without 50 µg mL−1 cPAC alone or in combination with 256 µg mL−1 SMX. Post infection mortality of flies was monitored daily for 14 days, with each treatment tested twice in triplicate. Additional details can be found in the Supporting Information.In Vivo Infection Assay Using Galleria Mellonella Larvae: Twenty G. mellonella larvae were injected with active cultures of P. aeruginosa per treatment. All injected larvae were incubated in Petri dishes at 28 °C under 30% relative humidity in the dark, and the number of dead larvae was scored daily post infection. A larva was considered dead when it displayed no vital signs in response to touch, followed by increased melanization. Additional details are given in the Supporting Information.Biofilm Assays: Biofilm formation was quantified using the standard microtiter plate model−6 and 10 × 10−6m, respectively.z‐stacks using a 63× objective on a Zeiss 800 confocal laser scanning microscope and rendered such that living cells are colored green, and dead cells are colored red as described in the Supporting Information.Modified Disk‐Diffusion Assay: A modified disk‐diffusion assay6 CFU mL−1 and plated on MHB‐II agar plate. Step 1: commercially available TET 30 µg or MIN 30 µg antibiotic disk  was placed on top of the inoculated agar surface and the plate was incubated at 37 °C for 18 h. Custom disks were prepared using sterile blank disks  supplemented with 400 µg glucose or 400 µg cPAC with or without 400 µg glucose and left to dry at room temperature. Step 2: The antibiotic disk was carefully replaced with custom disks containing glucose or cPAC or their combination, and the plate was incubated at 37 °C for an additional 18 h.Emergence of Resistance Analysis: For characterization of in vitro resistance evolution by standard sequential passaging technique,E. coli CFT073 and P. aeruginosa PA14 cells were grown to exponential phase in MHB‐II at 37 °C. MICs were determined by preparing twofold serial dilutions in 96‐well microtiter plates. Each well was inoculated with the desired bacterial strain, and the plate was incubated at 37 °C for 18 h under static conditions. Bacterial growth was assessed by i) monitoring the cell growth (observed as a pellet and turbidity) in the wells600nm). Bacterial suspension from sub‐MIC (0.5 × MIC) of TET or cPAC or cPAC+TET combination was used to prepare the inoculum for the next day MIC experiment by diluting it to a final concentration of ≈106 CFU mL−1 in MHB‐II. This was repeated for 21 passages, and the ratio of the MIC obtained during each day relative to the MIC at 0 day (first time exposure) was determined. The data were expressed as relative fold increase in MIC with each day or passage. Experiments were performed with biological replicates.Membrane Permeabilization and Membrane Integrity Assays: The outer membrane permeabilization activity of cPAC was determined by the NPN  assay,600 of 0.5–0.6 . The cells were harvested, washed, resuspended 4‐(2‐hydroxyethyl)‐1‐piperazineethanesulfonic acid (HEPES) buffer containing 1 × 10−3mN‐ethylmaleimide . Aliquots were mixed with NPN to a final concentration of 10 × 10−6m (in cell suspension), and fluorescence was measured using the microplate reader . The BacLight kit  was used to assess cell membrane damage,EtBr Efflux Assay: To assess the effect of cPAC on the inhibition of the proton motive force–driven multidrug efflux pump, an EtBr efflux assay was performed.600 of 0.8–1.0 . Cells were loaded in polystyrene microcentrifuge tubes (2 mL) and mixed with 5 × 10−6m EtBr and cPACs at 25% of their MIC or a 100 × 10−6m concentration of the proton conductor CCCP (Sigma‐Aldrich Canada) as a positive control. Replica tubes that did not receive cPACs or proton conductor served as negative controls. The tubes were incubated for 1 h . The inoculum then was adjusted to an OD600 of 0.4 with MHB‐II broth containing 5 × 10−6m EtBr, and 2 mL of aliquot of this mixture was pelleted . The pellets were incubated on ice immediately, resuspended in 1 mL of MHB‐II, and aliquoted (200 µL) into a polystyrene 96‐well, black, clear‐bottom plate . EtBr efflux from the cells was monitored at room temperature using the microplate reader . Readings were taken at 5 min intervals for 1 h to monitor efflux pump activity. The background fluorescence of the medium was subtracted from all measurements, and the assay was repeated independently in triplicate.In Silico Docking Analysis: 3DLigandSite server was used to predict ligand binding sites on targeted protein structures using an automated method by searching a structural library to identify homologous structures with bound ligands.http://www.swissdock.ch/) to confirm the accuracy and robustness of predicted docking complexes. The ligand docking methods are described in the Supporting Information.Statistical Analysis: Where indicated, a two‐tailed Student's t‐test (P < 0.05) was used to determine whether the presence of cPAC resulted in a significant difference compared to levels for the control. A two‐way analysis of variance (ANOVA), followed by Sidak's multiple comparison, was used for biofilm assays to analyze statistical significance of the difference in biomass. Fruit fly survival curves were prepared using GraphPad Prism 6  to perform a statistical log–rank (Mantel–Cox) test. Throughout the text, all of the changes (increase or decrease) reported were statistically significant. Statistically nonsignificant values were not mentioned in the text.Full Methods: Detailed procedures of all methods are available in the Supporting Information.Authors Nathalie Tufenkji and Vimal B. Maisuria have applied for a patent (WO 2017/096484) on the use of cranberry derived phenolic compounds as antibiotic synergizing agent against pathogenic bacteria. The patent application is presently under review by the USPTO, with both authors listed as inventors. All authors declare that they have no other conflicts of interest.SupplementaryClick here for additional data file.


Introduction: The conventional model of abdominal anatomy described multiple mesenteries. Dissection techniques were based on this. Recent studies demonstrate the mesentery is continuous from duodenojejunal flexure to anorectal junction. Given this, it is important to update dissection techniques related to the mesentery in the cadaveric setting.Materials and Methods: A technique of mesenteric dissection was developed and tested in a cohort of 20 adult human cadavers . As the technique enabled excision of the mesentery as a single unit, it was possible to characterize the anatomy of the ex vivo mesentery.Results: The technique developed enabled dissection of an intact and continuous mesentery in all cadavers examined. Examination of the ex vivo mesentery demonstrated that a mesoduodenum was present in all cases. The mesentery was continuous from the mesoduodenum to the mesorectum and ended at the level of the anorectal junction.Conclusions: A technique was developed that reproducibly enabled dissection of an intact and continuous mesentery from the duodenum to the anorectal junction. A mesoduodenum was consistently observed and noted to be in continuity with the remainder of the mesentery. According to the conventional model of abdominal anatomy, the mesentery is defined as a double fold of peritoneum, separated by fatty connective tissue containing vessels and nerves, suspending some parts of the intra-abdominal gut tube from the posterior abdominal wall . The namThe conventional model of mesenteric anatomy describes multiple mesenteries. According to this model, some regions of the intestine have associated mesentery and are “intraperitoneal” whilst others do not, and are described as “retroperitoneal” . RecentlRecently, we also demonstrated mesenteric continuity in the human cadaveric setting . This isthe mesentery,” and transverse and sigmoid colon .Twenty , donated, adult human cadavers that were embalmed and fixed by infusion of 10% formalin and stored in 10% formalin were used in this study. All the cadavers were examined All the cadavers used in this study were donated for medical education and research with due consent of the relatives of the deceased under statutory law and with institutional approval. Any further clearance from the Institutional Ethics Committee was not required.A protocol was developed, based on recent reports, enabling dissection of the mesentery in the cadaver. The protocol was applied to all cadavers. The steps of the protocol are as follows:in situ. The common bile and main pancreatic ducts were ligated and divided where they entered the second part of duodenum. Jejunal and ileal intestinal loops were reflected toward the left shoulder, thereby exposing the underlying mesentery.The anterior abdominal wall was opened and reflected from above downwards as per standard protocol for human cadaveric dissection , 26. TheThe peritoneal reflection at the lateral aspect of the ascending colon was divided, providing access to the plane formed by the colon and underlying fascia. These were separated, enabling detachment of the colon from the posterior abdominal wall  . The mesThe mesosigmoid was mobilized free from the posterior abdominal wall in a similar manner, the reflection was divided through and the attached region of the mesosigmoid was detached from the underlying fascia toward the midline. Detachment of the mesosigmoid was continued distally under the mesorectum, thereby detaching this from the surrounding musculoskeletal mainframe. This was completed as far distally as was possible, which usually corresponded to the level at which the pelvic floor was encountered. The anorectal junction was then ligated and divided.At this point the mesentery has been fully detached but remains connected at the major vascular trunks and also at the regions of peritoneal ligamentous connection. These were all then divided and it was then possible to remove the entire mesentery from the abdominal cavity.In all cases, detailed observations were recorded and photographed.A protocol for mesenteric dissection in the cadaver was generated as described above. The protocol was applied to all cadavers and enabled mobilization of the mesentery in each case. The same protocol was applicable irrespective of the sex or age of the cadaver.Once the mesentery was dissected a number of observations were made possible. In every case, the mesentery was continuous from the mesoduodenum to the mesorectum –5. This The anterior and posterior aspects of the mesentery were inspected. With exception of the mesoduodenum, all regions of the mesentery were apparent when viewed from front on As the mesentery was continuous, distinct anatomical boundaries were not apparent subdividing individual regions. Given this, regions were subdivided based on the region of intestine with which they were continuous. The small intestinal region of mesentery comprised the mesentery associated with the jejunum and ileum. The ileal region of mesentery was continuous above with the transverse mesocolon. The small intestinal region of mesentery was continuous with the mesentery of the ascending colon (the ascending or right mesocolon) , 2.The transverse mesocolon was continuous at the splenic flexure, with the mesentery of the left colon (the left mesocolon or descending mesocolon). The latter continued distally as the mesosigmoid which in turn led onto the mesorectum , 2. The The duodenum and mesoduodenum were located posterior to the composite mesentery of the small intestine, ascending and transverse colons , 3–5. ThIn all cadavers the mobilized mesentery was connected to the posterior abdominal wall at the superior and inferior mesenteric arteries , 6. All According to surgical dissections , 27, theThe present study confirmed the presence of regions of the mesentery associated with both the ascending and descending regions of colon. In the undisturbed state, these were flattened against the posterior abdominal wall (but separate from it). Previous studies have mistakenly interpreted these regions of the mesentery as parietal peritoneum of the posterior abdominal wall.According to the conventional model of mesenteric anatomy, the root of the mesentery corresponds to the area where the small intestinal mesentery inserts directly into the posterior abdominal wall , 28. As Here, we have developed a technique that consistently enabled us dissect an intact and continuous mesentery from the duodenum to the anorectal junction. We found a mesoduodenum in all specimens and it was continuous with the adjacent part of the mesentery.It is likely that the dissection approach described in this study, and designed specifically to excise an intact and continuous mesentery, will assist students of anatomy, surgery, and radiology in further exploring the mesentery. Classical methods of cadaveric dissection lead the student with the erroneous impression there are multiple individual regions of mesentery , 26. TheThe raw data supporting the conclusions of this manuscript will be made available by the authors, without undue reservation, to any qualified researcher.The patients/participants provided their written informed consent to participate in this study.AK, TJ, and VK conceived and designed the study. AK, MF, HK, VK, TJ, and GR acquired, analyzed, and interpreted the data. AK and TJ wrote the manuscript. JC edited the manuscript. All authors provided approval for the final manuscript.The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.


Health care associated urinary tract infections (HAUTI) is a common complicating factor of urological practice. It is unclear what the appropriate empirical antibiotic choices are and how infection control policies (ICP) influence this. The aim of this study is to use probabilistic approaches towards the problem. That is to determine the chances of coverage of empirical antibiotic choices in HAUTIs and their annual trends in Europe. In addition, the impact of departmental self-reported compliance with catheter management and regulated usage of prophylactic antibiotics policies was tested. The estimated chances of coverage of antibiotics and further probabilistic calculations are carried out using the Global Prevalence of Infections in Urology (GPIU) annual surveillance study European data.GPIU is a multi-state annual prevalence study conducted in urology departments to detect patients with HAUTIs, using the Center for Disease Control (CDC) definitions and antimicrobial resistance (AMR). In this analysis; the European cohort from 2005 to 2015 was used. The estimated chance of coverage for each antibiotic choice in HAUTIs was calculated using the Bayesian Weighted Incidence Syndromic Antibiogram (WISCA) approach. Annual trend of the overall cohort and number of appropriate antibiotic choices were estimated. Departments were compared according to their self-reported compliance to ICPs to determine if there was an impact on chances of coverage and appropriate antibiotic choices.We estimated that in most study years less than half of the single agent antibiotics and all combination options were appropriate for empirical treatment of HAUTIs. Departments with compliance to both ICPs were estimated to have 66%(2006) to 44% (2015) more antibiotic choices compared to departments with complete lack of compliance to the ICPs. In our estimates departments with adherence to a single policy was not superior to departments with complete lack of adherence to ICPs.Most single agent choices had limited coverage for HAUTIs and combination choices had improved chance of coverage. Optimal antibiotic selection decision should be part of decision experiments and tested in local surveillance studies. Departments with self-reported compliance to ICPs have more antibiotic choices and details of the compliance should be evaluated in future studies. The analysis herein showed that over the 10-year course there was no clear time trend in the chances of coverage of antibiotics (Bayesian WISCA) in European urology departments. Health care associated urinary tract infections (HAUTI) in urology are a complicating factor of health care and their prevalence is estimated to be 7.7% . UnfortuAlthough, surveillance data is useful for clinical decision making (stewardship) and policy development, has some limitations. The main one is derived from the conventional approaches to synthesize AMR data, which focus on the pathogens and their susceptibility profile for each antibiotic choice. Whereas, from a stewardship and clinical point of view for selecting the appropriate empirical treatment the more relevant question is: “Which antibiotic works best for the condition being treated?”. An alternative way to answer this question is through a compound measure called weighted incidence syndromic combination antibiograms (WISCA) . This isBayesian analytical approach can adequately address this issue. In brief, the Bayesian approach treats each time point as a set of prior information to build up towards the current information . Pa. Pa14]. nfection .From 2005 to 2015, 365 urology departments screened 22,263 cases and reported 1,468  symptomatic HAUTIs with microbiological proof of infection. Summary of patient acquisition according to STROBE guidance is provided in The WISCA approach was adopted within the Bayesian framework , 6. This1,…,pn), where pj is the probability of pathogen (j). The probability of an antibiotic choice to be sensitive to a certain pathogen is sampled through the Beta distribution . In both types we employ hierarchical modelling techniques on the GPIU data from the preceding two years of each studied year to calculate the informative priors. This is then combined with the raw data to obtain the posterior distributions for each studied year and calculate the Bayesian WISCA. A sensitivity analysis was conducted to determine the impact of the assumption of coding intermediate as resistant in the data set.Mainly we have two cores of calculations. The probabilities of etiological pathogens are sampled through the Dirichlet distribution  of antibiotic choices that are appropriate for empirical treatment with the lowest possible risk of failure. In Bayesian WISCA threshold of above 0.5 helps for classification, utilizing the mean value alone cannot represent the uncertainty of the estimate in a useful way. The Bayesian WISCA estimate uncertainty is the range of values it can achieve and is represented using the interquartile range (IQR). To account for the estimate uncertainty and derive more robust decisions the IQR was used to establish thresholds. This is briefly illustrated in While a Antibiotic choices with an estimated WISCA IQR below 0.5 are categorized as inappropriate antibiotics. Their chances of appropriateness are less than inappropriateness within the IQR of simulated samples. On the contrary antibiotic choices with an estimated WISCA IQR above 0.5 represents chances of appropriateness greater than inappropriateness within the IQR of simulated samples. Hence, those choices are categorized as appropriate antibiotics. For antibiotic choices with an IQR that overlaps the probability of 0.5 we are uncertain with their appropriateness. A summary of this stratification is provided in Adherence to two ICPs was reported by investigators. These are; catheter management policy and policy for regulated usage of prophylactic antibiotics in urology departments. Based on the reported ICP adherence, hospitals were stratified into three groups. These were;Complete adherence: adherence to both policies;Partial adherence: adherence to one policy amongst two; andAbsence of ICP adherence: adherence to none of the two policies.Bayesian WISCA values were estimated for these three categories. Probabilistic comparison was achieved with the inverse cumulative density function method to simulate 1000 WISCA samples for each policy. This is followed by comparing each sample between groups to determine the probability of the WISCA to be greater than the comparator. This process classifies each sample superior or not to the comparator for each antibiotic choice. A threshold of 75% is used as an acceptable level for deducing conclusions on the trends. For example, if the Bayesian WISCA values of an antibiotic in group x is greater than those of the same antibiotic in group y in 75% of the sampled cases, then the antibiotic shows a trend of superior appropriateness when applied in group x rather than in group y. Of note, conventional reporting of p-values was avoided within the Bayesian framework and estimates are presented with a degree of certainty [ertainty , 19.The analyzed data consisted of 1,468 cases from Europe diagnosed with HAUTI (according to CDC criteria) from 2005 to 2015. The annual prevalence of HAUTIs in Europe ranged from 3.8% (2006) to 11.8% (2011). Urology departments from 29 countries across Europe provided data. The number of patients screened, departments and countries participating, and prevalence of HAUTIs with culture proven infection annually are presented in The mean age of patients was 63.8 (IQR: 55–76) and gender ratio was 2:1 for male to female. The subgroups of diagnosis had a similar distribution .E.coli ranged from 33% (Cefepime-2015) to 100% (Imipenem-except 2008) for single agents and from 75% (Ampicillin with Beta Lactamase Inhibitor (BLI) +Aminoglycosides in 2015) to 100%  for combinations. These rates for E.coli were obtained from a sample size ranging from 3 cases (Cefepime–2015) to 61 cases (Gentamicin-2014) (The sensitivity rates for in-2014) . SensitiBayesian WISCA of antibiotics in HAUTIs of single agents ranged from 0.29 (IQR: 0.21–0.37) for Amp+BLI (2006) to 0.81(IQR:0.76–0.86) for Imipenem (2008)  . The estBayesian WISCA for single agents was for Imipenem in all consecutive years, which was above 0.7 in all instances. In all years except for 2015 there was at least one combination choice with an estimated Bayesian WISCA of greater than 0.8. Sensitivity analysis for the Bayesian WISCA did not impact the values , Ceftazidime , Cefepime , Gentamicin , Amikacin , Imipenem (2006–2015) and Ciprofloxacin . Throughout all study years Amoxicllin+BLI, Cefuroxime and Cefotaxime were categorized as inappropriate. Unlike the single antibiotic choices, all combination agents were classified as appropriate throughout the study years except for 2009 where we were uncertain with one combination choice.The proportion of single agent antibiotics classified as appropriate (WISCA IQR>0.5) fluctuated throughout the years without an obvious trend . HighestBayesian WISCA.Analysis of the established threshold was repeated with an increase of 0.1 increments. The results for single agent antibiotic choices are illustrated in Bayesian WISCA values of antibiotics in departments with different ICP adherences are illustrated in The Partial adherence vs. absence of ICPs: The estimated WISCA IQRs showed overlap in most time points in these two categories . We are Complete adherence vs partial adherence: The number of superior antibiotic choices over the study years ranged between two (11%) (2007–2008) to 16 (88%) (2013) . AmongstComplete adherence vs. absence of ICP: Number of superior estimates of antibiotic choices ranged between 0 (2007–2008) to 13 (72%) (2015) . From 20Bayesian WISCA in European urology departments for HAUTIs defined by strict criteria (CDC) over a period of 10-years. We estimated that the mean Bayesian WISCA value for single agent antibiotic choices ranged from 0.29 (Amp+BLI in 2006) to 0.81 (Imipenem 2008). Combination of antibiotic choices showed an increase in the estimates. By further utilizing the analytic methods we were able to stratify the antibiotic choices as appropriate, inappropriate and equivocal for empirical treatment of HAUTIs. We estimated that half of the single antibiotic agents are inappropriate and for one third of them we are uncertain. In our estimates all combination agents remained appropriate throughout the study years. Our analytical approach has also demonstrated that self-reported adherence to a range of infection prevention policies coincides with higher number of antibiotic choices.We evaluated the chances of coverage of empirical antibiotic choices through the Bayesian analytical approach was utilized, which to our knowledge was first used by Bielicki J.A. et al . In their study, the Bayesian WISCA was used to select appropriate empirical antibiotics for blood stream infections in a pediatric population. However, they used a non-informative prior, which means they didn’t account for prior year surveillance data. In our study we used robust validated methods  to include the prior year data (informative prior) when calculating the Bayesian WISCA value [Bayesian approach into WISCA with an informative prior has facilitated to obtain probabilities of coverage for antibiotic choices with their respective level of uncertainty.Chance of providing coverage (WISCA) is a relatively new concept for evaluating antibiotics by accounting for both frequency of HAUTI pathogens and their respective AMR , 20, 21.CA value . In brieBayesian WISCA values of the studied antibiotics showed fluctuations over the 10-year period but lacked a clear time trend. We further assessed the antibiotic choices by establishing cut-off values to determine if an antibiotic would be an appropriate choice for empirical treatment. Similarly, this approach also did not demonstrate a time trend in the proportion of appropriate antibiotic choices. However, this finding should be interpreted with caution as we are uncertain with at least 20% of single agent choices. We also conducted a threshold analysis, whereby the threshold was gradually increased at an increment of 0.1. This demonstrated that in several years the threshold could be increased to 0.6 without a decrease in the number of appropriate antibiotics. This exploratory analysis is particularly important as it can be utilized in local surveillance data to establish the optimal decision for appropriate antibiotic lists whilst controlling for risk of failure.The Bayesian WISCA proposing a plausible strategy for complicated, severe HAUTIs such as urosepsis. For example, the mean Bayesian WISCA estimate of Amp+BLI alone ranged between 0.29  to 0.46  and for Gentamicin alone ranged from 0.46  to 0.65 . The combination of these two antibiotics lead to a substantial increase in the mean Bayesian WISCA estimate ranging from 0.56  to 0.76 . This combination choice, like other Beta-lactam and Aminoglycoside combinations, is estimated to have a similar chance of coverage with broad spectrum antibiotics such as Imipenem and Piperacillin/Tazobactam that should be conserved as much as possible in the face of increasing antibiotic resistance. The examples provided illustrate the need for careful interpretation of the obtained estimates. Moreover, the Bayesian WISCA can facilitate finding effective strategies for selecting appropriate antibiotics for empirical treatment. We would also stress out the importance of making better choices of empirical treatments with the Bayesian WISCA. If one opts to obtain an absolute certainty of complete coverage of pathogens with empirical treatment the Bayesian WISCA (estimate of 1 with no uncertainty) then multiple agents and classes of antibiotics would be combined. This would, however, defeat the purpose of antibiotic stewardship and optimization of choices.It should be emphasized that by classifying an antibiotic as inappropriate in this study we are not suggesting them to be redundant and we encourage their utility in the presence of culture and sensitivity results if proven to be sensitive. Optimal antibiotic selection approaches are still to be discovered, but in our study, we confirmed that combination options improve the Bayesian WISCA tools. ICPs can reduce the need (less infection episodes) and demand (responsible use) for antibiotics [Bayesian WISCA framework to obtain comparable and reliable outcomes, which is one of the main difficulties of infection related policy studies. In our study, comparison of ICPs was carried out by utilizing probabilistic and simulation methods.As part of our work we carried out an exploratory analysis of the impact of ICPs on appropriate antibiotics through the ibiotics . The polibiotics . In our Bayesian WISCA are required. Nevertheless, our study does provide an overall trend over a 10-year period in urology practice. Finally, we have not accounted for the geographical variation in Europe. This was due to insufficient data to represent certain areas and would generate uncertain results although the mean estimates would not change.Despite the advantages of the novel approach we adopted in analyzing HAUTIs there are certain limitations that require attention. Firstly, the GPIU surveillance study gathers data from urology departments through an altruistic contribution. Therefore, insufficient sampling of the HAUTI population is of concern. However, departments contributing to this study do have a high level of awareness of AMR issues. Therefore, even if our results are based on an incomplete representation, its more likely to be the optimal section of the population. Secondly, only two ICPs were evaluated and unfortunately the local practice of these ICPs is not known. Thirdly, these estimates represent a sampled population in Europe at given time points and cannot be used to derive local empiric antibiotic policies. By pooling different hospital data, the inter-hospital heterogeneity has not been accounted for. We could have preferred to subgroup the samples of each hospital, but this would lead to very low sample sizes and unreliable estimates. Studies to assess inter-hospital heterogeneity as part of the Bayesian WISCA approach adopted should be repeated in local surveillance studies to improve local policy recommendations.In conclusion, we were able to estimate that there was no clear time trend in chances of coverage of the antibiotic choices in European urology departments. Departments with self-reported adherence to ICPs have more antibiotic choices. Future studies should focus on determining the optimal selection of antibiotics for subgroups of HAUTIs. Moreover, the S1 Fig(DOCX)Click here for additional data file.S2 Fig(DOCX)Click here for additional data file.S1 Appendix(DOCX)Click here for additional data file.S2 Appendix(DOCX)Click here for additional data file.S3 Appendix(DOCX)Click here for additional data file.S4 Appendix(DOCX)Click here for additional data file.S5 Appendix(DOCX)Click here for additional data file.S1 Table(DOCX)Click here for additional data file.S2 TableA. Number of departments from each European country per year. (“x” refers to no registries from the country on the GPIU study year). B. Number of patients surveyed and the prevalence of HAUTIS per year.(DOCX)Click here for additional data file.S3 Table(DOCX)Click here for additional data file.S4 Table(DOCX)Click here for additional data file.