In addition, a series of compression simulations carried out using the PFC2D software are also presented for comparison. The results show the following: (1) with an increase in dry–wet cycles, the damage to the concrete gradually increased, and adding nano-TiO2 into ordinary concrete can improve the material’s sulfate resistance; (2) after 50 sulfate dry–wet cycles, the mass loss rate of ordinary concrete was –3.744%, while that of nano-TiO2-modified concrete was −1.363%; (3) the compressive strength of ordinary concrete was reduced from 41.53 to 25.12 MPa (a reduction of 39.51%), but the compressive strength of nano-TiO2-modified concrete was reduced from 49.91 to 32.12 MPa (a reduction of 35.64%); (4) after a sulfate dry–wet cycle, the nano-TiO2-modified concrete surface produced white crystalline products, considered to be ettringite based on the XRD analysis; (5) when considering the peak stress and strain of the concrete samples, the numerical results agreed well with the test results, indicating the reliability of the method.This study compared the effects of the sulfate dry–wet cycle on the properties of ordinary concrete and nano-TiO Pozzolan can react with Ca(OH)2, so that there is not enough Ca(OH)2 in the paste to react with sulfate [3AH6 more stable and promotes the reaction of Ca(OH)2 with silica [In recent years, there has been an increase in the number of construction projects worldwide; as a result, the use of concrete materials has increased year on year. Due to the influence of the environment, concrete is inevitably influenced by sulfate in nature; in particular, the influence is more significant in coastal areas. Normally, solid salts cannot erode concrete; however, when it exists in the form of a solution, it reacts with concrete, which can not only cause harmful expansion and cracking, but can also reduce the bond strength between the cement slurry itself and the aggregate ,2,3,4. A sulfate ,6,7. In h silica ,9. Moreoh silica . The freh silica , inorganh silica ,13. The 2 particles in concrete. Thus, this article, through a nano-TiO2 concrete experiment, mainly discusses its influence on the resistance of concrete to sulfuric acid attack.A large number of studies have shown that nanomaterials can improve the microstructure and increase the impermeability of concrete ,15, amon2-modified concrete by PFC. Some properties of concrete can be predicted by the simulated specimen, such as how many tensile cracks and shear cracks are produced in the failure.At present, the finite element, block discrete element, and particle flow methods are frequently used to analyze the mechanical properties of concrete structures. The finite element method is suitable for the analysis of deformable media, yet it cannot reflect the complex interaction between particles and highly nonlinear behavior and cannot describe the fluid deformation characteristics of bulk materials . The fin2 on the resistance of concrete to sulfuric acid attack, including mass loss rate, ultrasonic wave velocity, compressive strength, and XRD analyses. The compression simulation of ordinary and nano-TiO2 concrete was carried out by PFC2D software. The micro parameters of concrete in PFC software are obtained. When considering the peak stress and strain of the concrete samples, the numerical results agreed well with the test results, indicating the reliability of the method.In general, the main subject of this paper is the influence of nano-TiO2, sulfate, water-reducing agent, and water. The cement was a conch brand, PO42.5 grade, plain Portland cement; its relative density was 3.12 g/cm3. The main chemical components of the cement are shown in 3. The anhydrous sodium sulfate was a white powder with hygroscopicity, easily to dissolved in water, and the aqueous solution was neutral. The water reducer was made of BASF 2651F, which was a modified polycarboxylic ether made by the spray-drying process. It had good fluidity, a uniform color, and an obvious increase in strength. The titanium dioxide was white; the details of nano-TiO2 are shown in The raw materials included gravel, cement, sand, nano-TiO2 has strong water absorption. When the content nano-TiO2 reaches 5%, the concrete is difficult to mix and form, so the use of a water reducer was necessary. A water reducer ensures that the nano-TiO2-modified concrete becomes a test specimen. In order to reduce the influence of the water reducer on the test results, the two groups used the same 4.1 g amount of water reducer, and nano-TiO2 accounted for 3% of cement in this paper , the mixing procedure was completed to put the mixture into the mold for molding. The size of the compression specimen was 100 mm× 100 mm× 100 mm.To begin, some exploratory tests were carried out and it was found that nano-TiO2-modified concrete after the dry–wet cycles is shown in The specimens were cured for 28 days after the preparation. Then, their surfaces were wiped clean with a wet cloth. Next, the specimens were put into an 80 °C dryer and dried for 2 h. After drying, the specimens were numbered and weighed, and their initial quality and ultrasonic wave velocity were recorded. Thereafter, the samples were put into the sulfate dry–wet cycle testing machine. At the same time, the 5% sodium sulfate solution was injected into the machine until the liquid level was 5 mm higher than the top of samples. The setting of the dry–wet cycle machine one stage every 10 dry–wet, with each cycle lasting 24 h, in which the sulfate soaking time was 15 h and the temperature stage was 30 °C. The drying time was 6 h and the temperature was 80 °C. After 20, 30, 40, and 50 dry–wet cycles, the mass loss rate and ultrasonic wave velocity of each stage were calculated. The surface of the nano-TiO2-modified concrete experienced a small positive increase of 0.072% at 10 cycles and then gradually decreased. Because fine cracks appeared on the surface of the nano-TiO2-modified concrete at 10 cycles, which led to the growth of mass loss, with a further increase in dry–wet cycles, the fine cracks gradually expanded and the sulfate solution entered the surface of the specimen to produce a crystalline powder, which resulted in a decrease in the mass loss rate of the specimen. After 50 dry–wet cycles, the mass loss rate of the ordinary concrete was −3.744%, while the mass loss rate of nano-TiO2-modified concrete was −1.363%. There were few crystalline products in the cracks of the nano-TiO2-modified concrete, which confirms that nano-TiO2 improves the impermeability of concrete and reduces the gap products.The mass loss rate of the specimen after the dry–wet cycle is shown in 2-modified concrete was 3610 m/s at the beginning. From 0 to 30 dry–wet cycles, the ultrasonic wave velocity of the nano-TiO2-modified concrete was always in a declining stage, which confirms that the nano-TiO2-modified concrete had been eroded by sulfate. In the 30–40 dry–wet cycles, the ultrasonic wave velocity of the nano-TiO2-modified concrete remained stable. After 50 dry–wet cycles, the ultrasonic wave velocity of the nano-TiO2-modified concrete was 2612 m/s .The ultrasonic wave velocity of the specimen after dry–wet cycles is shown in 2-modified concrete decreased with the increase in dry–wet cycles. In the beginning, the maximum average compressive strength of the ordinary and nano-TiO2-modified concrete was 41.53 and 49.91 MPa, respectively. The average maximum compressive strength of the concrete with nanoparticles increased by 20.17%. After 50 dry–wet cycles, the compressive strength of the ordinary concrete decreased by 39.51% (from 41.53 to 25.12 MPa), while the compressive strength of the nano-TiO2-modified concrete decreased by 35.64% (from 49.91 to 32.12 MPa).The compressive strength of the specimen after the dry–wet cycles is shown in 2-modified concrete at peak stress increased by approximately 0.5 × 10−3. After 50 dry–wet cycles, the strain corresponding to the peak stress of the ordinary and nano-TiO2-modified concrete decreased by approximately 1.9 × 10−3. The influence of the dry–wet cycles on the compaction and elastic stages was small. The stress–strain trend of the ordinary and nano-TiO2-modified concrete was similar. However, in the yield stage, it had a certain influence: At 20 dry–wet cycles, the specimens showed dispersion after the peak, and the ductility of some of the specimens increased.The stress–strain of the specimen after the dry–wet cycles is shown in 2-modified concrete under normal temperature curing and after the dry–wet cycles. As can be seen, there are several diffraction peaks in the nano-TiO2-modified concrete cured at room temperature: After comparing and analyzing the corresponding characteristic angles, quartz, calcium carbonate, calcium silicate hydrate, etc., were found. There were quartz, calcium carbonate, calcium silicate hydrate, and Ettringite in the spectrum of the nano-TiO2-modified concrete after the dry–wet cycles. Quartz is the main component of sand, calcium carbonate comes from the limestone and the carbonation reaction in the environment, hydrated calcium silicate is the hydration product of cement slurry, and ettringite is the product of sulfate attack. Sulfate attack is a complex physical–chemical process, and it is generally believed that the process of sulfate attack on concrete consists of the following five main chemical reactions 22:2O, CaO, Al2O3, and SO3, respectively. Products such as ettringite and dihydrate gypsum expand by absorbing water, which destroys the micro-housekeeper structure of concrete.2-modified concrete produced 10,502 particles, as shown in 2-modified concrete were filled with a large number of red nanoparticles. When the initial model was generated, the contact accuracy in the model system was not great enough, and there was an interaction between particles. Thus, the initial model was unable to simulate the specimen well, which could be solved by the servo mechanism. When the ratio of the average unbalance force to the average contact force was less than 1 × 10–5, the servo system was stopped, and the specimen state reached stability.PFC2D software was used for modeling. The calculation unit of the aggregate was spherical particles. The size of the specimen was 100 mm × 100 mm, where the ordinary concrete produced 7080 particles, as shown in 10 Pa, the stress of the simulated specimen hardly increases, so it can be roughly estimated that Pb_emod and Cb_emod are between 5 × 108 and 2 × 1010 Pa. With the increase in Ten and Coh, the maximum compressive stress and the corresponding strain increased. It can be roughly estimated that Ten is between 5 × 106 and 5 × 108 Pa. When Coh is 1 × 108 and 5 × 108, the stress–strain curves of the two specimens coincide, it can be roughly estimated that the Coh is between 5 × 106 and 1 × 108 Pa. At the same time, however, the slope remained unchanged, which means that there was no effect on the compressive modulus of elasticity. Through parameter calibration, the micro-parameters of the two types of concrete were obtained, as shown in 2-modified concrete. The parallel effective modulus, tensile strength, and bonding strength of the ordinary concrete were 28.05 GPA, 25 MPa, and 100 MPa, respectively. After 50 dry–wet cycles, the half-particle parallel effective modulus, tensile strength, and bonding strength of the ordinary concrete were 25 GPA, 11 MPa, and 90 MPa, respectively. Meanwhile, the parallel effective modulus, tensile strength, and bonding strength of nano-TiO2-modified concrete were 28.05 GPA, 31 MPa, and 100 MPa, respectively. After 50 dry–wet cycles, the half-particle parallel effective modulus, tensile strength, and bonding strength of the nano-TiO2-modified concrete were 10 GPa, 17 MPa, and 80 MPa, respectively. This reflects the erosion of concrete caused by the dry–wet cycles, which led to the performance degradation of the particles.The parallel bonding model was used in the simulation. The contact force between the particles came from the contact force generated by the overlapping of particles and from the bonding force and torque generated by the parallel bonding model. When bonded, it can resist torque and become linear elasticity until the force exceeds the strength limit and the bonding model is destroyed. Due to the dry–wet cycles, some of the particles became soft, and two groups of parallel bonding combinations were used to reflect the softening phenomenon: First, the influence of four main parameters on compressive stress–strain was studied. 2-modified concrete. It can be seen that the number of cracks in the ordinary concrete is more than that in the nano-TiO2-modified concrete. −3. Meanwhile, the simulated peak stress of the ordinary concrete was 26.4 MPa, and the corresponding strain was 2.27 × 10−3. The difference between the test and simulation peak stress was 2.05%, and the corresponding strain difference was 14.98%. Meanwhile, after 50 dry–wet cycles, the peak stress of the nano-TiO2-modified concrete compression test was 33.82 MPa, and the corresponding strain was 1.86 × 10−3, while the simulated peak stress of the nano-TiO2-modified concrete was 32.3 MPa, and the corresponding strain is 2.34 × 10−3. The difference between the test and simulation peak stress was 4.71%, and the corresponding strain difference was 20.51%. It can be seen that the simulation materials well reflect the mechanical properties of raw materials, especially the peak compressive strength.2 on the resistance of concrete to sulfuric acid attack, including mass loss rate, ultrasonic wave velocity, compressive strength, and XRD analyses. The compression simulation of ordinary concrete and nano-TiO2 concrete was carried out by PFC2D software. The result showed that with an increase in the number of dry–wet cycles, the damage to the concrete gradually increased, and adding nano-TiO2 improved the sulfate resistance of the concrete. After 50 dry–wet cycles, the mass loss rate of the ordinary concrete was −3.744%, while that of the nano-TiO2-modified concrete was −1.363%. The compressive strength of the ordinary concrete decreased by 39.51% from 41.53 to 25.12 MPa, while the compressive strength of the nano-TiO2-modified concrete decreased by 35.64% from 49.91 to 32.12 MPa. After the sulfate dry–wet cycles, white crystalline powder was produced on the surface of the nano-TiO2-modified concrete, identified as ettringite by XRD analysis. Thus, the simulation materials by PFC2D can well reflect the mechanical properties of raw materials, especially the peak compressive strength.The main subject of this paper was the influence of nano-TiO


The onset of bloody stools in neonates often results in antibiotic treatment for suspected necrotizing enterocolitis (NEC). Food protein-induced allergic proctocolitis (FPIAP) is an often-neglected differential diagnosis. We performed a retrospective analysis of antibiotic exposure at our tertiary center from 2011 to 2020 that included three time periods of differing antimicrobial stewardship goals. We compared these data with the conventional treatment guidelines (modified Bell’s criteria). In our cohort of 102 neonates with bloody stools, the length of antibiotic exposure was significantly reduced from a median of 4 to 2 days. The proportion of treated neonates decreased from 100% to 55% without an increase in negative outcomes. There were 434 antibiotic days. Following a management strategy according to modified Bell’s criteria would have led to at least 780 antibiotic days. The delayed initiation of antibiotic treatment was observed in 7 of 102 cases (6.9%). No proven NEC case was missed. Mortality was 3.9%. In conclusion, with FPIAP as a differential diagnosis of NEC, an observational management strategy in neonates with bloody stools that present in a good clinical condition seems to be justified. This may lead to a significant reduction of antibiotic exposure. Further prospective, randomized trials are needed to prove the safety of this observational approach. In neonatology units, the onset of bloody stools often results in the initiation of diagnostic procedures and preventive treatment for possible necrotizing enterocolitis (NEC). Early detection of high-risk neonates presenting with NEC as well as immediate initiation of therapy is crucial for the improvement of patients’ outcomes and mortality rates ,2,3. TheNEC is one of the leading causes of morbidity and mortality in preterm neonates and particularly affects low birth weight (LBW) infants in neonatal intensive care units (NICUs) . Its incBy contrast, FPIAP is a benign disease, that is mostly caused by cow milk protein or soy protein-based infant feeds ,20,21. EIt is challenging in a neonate with rectal bleeding to differentiate between the first symptoms of NEC and FPIAP, especially in preterm infants, where untreated NEC may lead to rapid deterioration with sepsis and the development of severe NEC. Facing this potential risk, most physicians tend to start full NEC treatment, including the initiation of antibiotic therapy and parenteral nutrition (PN) ,27,28,29n = 5), motility disorders such as Hirschsprung’s disease (n = 6) or isolated gastric perforation (n = 1). A total of 43 of the remaining 102 neonates were stratified into Bell IB (42.2%), 50 (49.0%) into Bell II (Bell IIA: 25 (24.5%), Bell IIB: 25 (24.5%)) and 9 (8.8%) into Bell III based on clinical signs as well as radiological and laboratory findings  during the whole study period (2011–2020) was 4 days (range 0–24 days) (n = 102) in our cohort summed up to 434 antibiotic days. If all the neonates had been treated according to the therapeutic guidelines of modified Bell’s staging criteria for NEC, the overall number would have resulted in at least 780 antibiotic days.The median antibiotic exposure of all the neonates (24 days) . A total24 days) . The med24 days) a. Furthe24 days) . Compari24 days) b. AntibiIn seven neonates (6.9% of the whole cohort) with antibiotic exposure, treatment was not initiated immediately after symptom onset. All these patients did not show worsening of their general condition at that time. In three, antibiotic therapy was started due to the persistence of bloody stools; in the other four neonates, antibiotic therapy was started later due to radiological or laboratory findings. Antibiotic therapy was not escalated in the further course with any of these neonates and none needed surgery for NEC treatment nor died during hospitalization.Four neonates (3.9%) died during hospitalization . All theThe data on the feeding regimes before symptom onset were available from 95 of 102 neonates. A total of 69 out of 95 neonates (72.6%) were exclusively breast-fed, whereas 26 (27.4%) received at least partial formula-based feeds. The percentage of neonates with formula-based feeds divided by NEC stages are shown in The possible risk factors before symptom onset for the patients divided by NEC stages according to Bell is displayed in During the 10 year study period, a significant reduction of antibiotic exposure in neonates with bloody stools that were hospitalized in our NICU or neonatal ward was observed without an increase of negative outcome.While in the period of 2011 to 2012, all the neonates were treated according to therapeutic guidance by modified Bell’s criteria as suspected NEC with the administration of antibiotic therapy and parenteral nutrition, the proportion of patients with antibiotic exposure dropped significantly to 55% in the period of 2017 to 2020. Furthermore, the duration of antibiotic therapy for the whole cohort declined significantly from 4 days to 2 days. The highest reduction in antibiotic exposure was most noticeable in newborns with NEC stage IB. Generally, the reduction of antibiotic exposure was not associated with an increased risk of missing proven NEC cases or an increase in negative outcomes. Comparing antibiotic exposure according to the therapeutic guidelines of the modified Bell’s staging criteria for NEC, we were able to reduce the number of antibiotic days by at least 44%. This underlines the robustness of the observed effect and supports the generalization of our results [The proportion and duration of antibiotic treatment, the amount of administration of parenteral nutrition, and the number of performed surgeries was higher with higher NEC stages according to Bell’s classification. This was expected and was in accordance with the therapeutic guidelines of modified Bell’s staging . MortaliSo far, there are not many studies published that question the necessity and threshold of antibiotic treatment in newborns with bloody stools. Maayan-Metzger et al. published a study comparing the management of isolated rectal bleeding (IRB) in newborns at two different time periods. They showed that a reduction in the length of antibiotic treatment and nil per os (NPO) did not lead to the deterioration of their patients’ clinical condition . LenfestOur study results and the observed courses of neonates with bloody stools in our cohort underline that symptoms’ onset might often not be associated with NEC but with an atypical/early-onset type of FPIAP. We therefore hypothesize an overall overtreatment of neonates with bloody stools and advocate a more restricted use of antibiotics in term and preterm newborns with bloody stools on NICUs and neonatal wards, respectively. FPIAP should be considered as primary diagnosis in neonates with bloody stools who appear to be in good clinical condition and show only minor or no abnormalities in laboratory or radiological examinations (Bell IB). Currently, antibiotic stewardship is mandatory for every neonatal unit. Nevertheless, research shows that adherence to antibiotic stewardship programs is not easy to obtain and that the fear of sepsis is a major driver for the overuse of antibiotics ,36. PoteOur secondary objective in our cohort of neonates with bloody stools was to analyse the association of risk factors with higher NEC stages. Many risk factors for NEC are correlated among each other and a bivariate analysis is problematic. Therefore, the risk factors in Due to the retrospective design as the main limitation of our study, we are not able to prove a causal relationship between antibiotic stewardship policies and reduced exposure to antibiotics. Nevertheless, the effect size is highly noticeable without other explanation of the observed effect. The retrospective design is even more of a limitation regarding the analysis of the risk factors of proven NEC cases. The observation of historically established risk factors and pathological diagnostics for NEC, as well as the use of Bell’s classification. may lead physicians to diagnose NEC cases and to start antibiotic treatment. Although stage III NEC may be taken as proof of NEC, there is no clear gold standard for the diagnosis. Due to safety aspects, the early administration of antibiotics for NEC stage IIA and B cases seems to be reasonable; we may challenge the indication for neonates with NEC stage IA and B. Nevertheless, due to the retrospective design, future studies are needed to prove the safety of our approach.This is a retrospective, single-centre cohort study analysing risk factors, clinical courses, therapies, and outcome with focus on the antibiotic stewardship of neonates with bloody stools hospitalised at the Children’s Hospital in Lucerne, Switzerland. The study was approved by the national Swiss Ethics Committee, which consented to the collection of individual data.Included were all newborns  with bloody stools that were hospitalized in the NICU or neonatal ward at the Children’s Hospital of Lucerne between January 1, 2011 and June 30, 2020. Neonates with apparent explanations for their bloody stools, such as anal fissures or swallowed maternal blood, as well as neonates with congenital anomalies or enteral infections, were excluded.We classified the neonates into NEC stages I-III, according to the modified Bell’s classification of NEC  based onThe Children’s Hospital of Lucerne is a tertiary neonatal centre in Central Switzerland, where birth rates are around 7000 deliveries annually. The Children’s Hospital of Lucerne is responsible for special care for all neonates, including intermediate and intensive neonatal care as well as paediatric surgery within Central Switzerland.During the observed time period of 10 years, the management of neonates with bloody stools changed. During 2011–2012, neonates with bloody stools were always managed for a working diagnosis of NEC and classical NEC management was started until NEC was excluded. In the following years (2013–2016), there was growing evidence that NEC might not be the cause of the onset of bloody stools, but it was suggestive of an early-onset/atypical form of FPIAP and, therefore, the management changed slowly. Neonates without risk factors or clinical signs of infection, or with normal further work-up, were increasingly observed. During this period of time, antibiotic stewardship was implemented for suspected neonatal early-onset sepsis, catheter-related blood stream infections and ventilation-associated pneumonia at our centre . During The primary outcome was defined as the exposure to antibiotic treatment within three different time periods of antibiotic stewardship (2011 to 2012 versus 2013 to 2016 versus 2017 to 2020) for the whole cohort and for different NEC stages and in comparison with therapeutic guidance by the modified Bell’s staging criteria. Mortality within the three different time periods was defined as a secondary outcome.As a secondary objective, we investigated the possible differences in risk factors between the different NEC stages according to Bell.Neonates with bloody stools were identified through the hospital-based electronic database for diagnoses. Allergic and food-induced gastroenteritis or colitis, necrotizing enterocolitis, melena, rectal bleeding, and other diseases of the alimentary tract in newborns were used as search terms. For all the identified neonates, a retrospective chart review of the patient’ data and clinical courses was performed. The following data were collected and pseudonymised. The newborns’ clinical/birth characteristics included: gestational age (GA), birth weight (BW), gender, risk factors for NEC/comorbidities  or small patent ductus arteriosus (PDA))/with hemodynamic relevance but no need for surgery )/with hemodynamic relevance and need for surgery ), perinatal asphyxia, small for gestational age (SGA), sepsis, RBC (red blood cell) transfusion, PT (platelet transfusion), FFP (fresh frozen plasma) transfusion, hypotonia with need for vasopressors, antibiotic treatment before symptom onset, feeding regimen before onset). Furthermore, we evaluated the clinical symptoms , as well as the radiological and laboratory findings and therapy , change of feeds, surgery) and the neonates’ outcome.The data for the risk factors, therapies, and outcomes were evaluated in a descriptive manner by NEC stages. The categorial data were displayed as absolute and relative frequencies. The continuous variables were described using descriptive statistics including median, first and third quartile  and/or range (minimum–maximum). The comparisons between the risk factors and NEC stages were performed utilizing the Kruskal—Wallis test and Fisher’s exact test. Rank correlation coefficients  were calculated to explore potential associations with increasing NEC stages. Multiple, ordered regression analysis was performed to assess potential associations of risk factors and higher NEC stages, applying Akaike’s model selection criterion. These analyses are purely exploratory and hypothesis-generating. Therefore, no adjustment for multiple testing was made. A level of significance of 0.05 was adopted. The statistical analyses were performed using Stata .In conclusion, our study questions the necessity of antibiotic treatment for all neonates with bloody stools according to the management guidance in the modified Bell’s criteria for suspected NEC. With FPIAP as the main differential diagnosis, it seems to be justified to follow an observational management strategy in patients that appear to be in good clinical condition, which may lead to a significant reduction in antibiotic exposure. Further prospective, randomized trials are needed to prove the safety of this observational approach.


The availability of different lithology with which concrete can be packaged could create substantial questions on the differences that they can provide to the same mixture. Different kinds of aggregates were analyzed individually to investigate their main characteristics, which allowed us to package five types of concrete mixtures. These five mixtures were compared to each other through compressive strength values. Furthermore, it was considered microscopically what possible differences could exist between these different mixtures, for example, differences in the cement/aggregate reaction. The chemical characterization of the aggregates, used as the skeleton of the cement mixes, was proposed as an important investigative phase in order to better understand the differences in the geotechnical and physical-mechanical characteristics and to verify the presence of any harmful phases for the durability of the concrete. The development of society has led to a continuous improvement of the construction techniques to create voluminous buildings ,2. Concrcaementum mixed with lime and a pulvis puteolana (pozzolanic powder) which constituted the binder of the mixture [Since ancient times, the use of binders and similar materials characterized the history of man’s settlements, but only with Romans concrete was used as a modern connotation ,6. In fa mixture ,8.Nowadays, concrete indicates a conglomerate formed by cement, aggregates  and water which, hardening, gives rise to a real artificial stone . In modeThe apparently simple composition of the concrete underestimates the problems of degradation that can arise in the short and long term due to the presence of macro and micro pollutants or to reactivity with the aggregates ,13. AfteThe Council Directive 89/106/EEC declares that construction products must possess characteristics that impose important requirements of mechanical strength and stability, safety in case of fire, energy saving, protection against noise, hygiene and safety in use . On May In addition, the UNI EN 12620:2013 deals with the correct qualitative characterization of the aggregates that must be used in the packaging of concrete .For all these reasons, a correct assessment of the medium- and long-term effects is necessary to verify the suitability of the materials both at the delivery of the work and after periods of exposure to the mechanical stresses imposed by anthropogenic activities  and to tThis study aimed to characterize the lithic component of the concrete with specific laboratory tests aimed at highlighting its strengths and defects in the best possible way. Furthermore, we wanted to petrographically and mechanically compare mixtures of concrete made with aggregates of different types and different genesis: e.g., natural conglomerates with a high form factor with a smooth surface, originated from quarries in different regions; and artificial breccia obtained by crushing natural conglomerates and characterized by irregular morphology and high surface roughness.The aggregates used in the construction field come from the processing of natural deposits geologically called conglomerates, consolidated sedimentary deposits consisting of a preponderant content of more or less rounded pebbles and gravels ,21. The The suitability of the different types of aggregates was determined using the main laboratory tests, physical-mechanical and thermal, which the UNI EN standard normally requires from producers of aggregates ,25,26,27Three different types of aggregates were compared: (a) conglomerate of carbonate sedimentary rocks from Nervesa della Battaglia ; (b) conglomerate of silicate and carbonate metamorphic rocks from Santhià ; and (c) artificial porphyry aggregates from waste processing in the extraction of slabs and blocks for ornaments from Segonzano .The metamorphic aggregates, on the other hand, came from the selection of alluvial conglomerate gravels of the Vercelli plain originating by the fluvioglacial activity between the Riss and Würm glaciations (moraine amphitheater of Ivrea) . SamplesFinally, the porphyry aggregates were obtained from the processing of rhyolitic ignimbritic deposits of the Atesina porphyritic platform that originated following the Permian volcanic activity . The cruIn addition, two different calcareous sand samples were used, characterized by different sizes 0/6 and 0/1, as shown in For each of these three types of aggregates, concrete mixtures were made both with aggregates from the original conglomerates and with materials obtained from their crushing.The preparation of a single type of mixture with the use of the same water/cement ratio (w/c) but with different aggregates highlights possible strengths and weaknesses of some lithologies rather than others. The description of the mixtures was better described in For the fine fraction, a medium-coarse sand with calcareous gravel and a medium-fine sand  were usFirst of all, specific analyses were carried out on the individual aggregates to evaluate all their characteristics in order to then be able to establish the parameters necessary to create the concrete mixes. All the analyses were carried out at the Laboratory of the Department of Physics and Earth Sciences of the University of Ferrara .The analyses performed on the individual aggregates were: particle size analyses ,35,36,37Petrographic analysis is important to identify the presence or not of minerals responsible for the alkali–silica reaction ,39. It iThe analyses of the single aggregates made it possible to identify the characteristics of the analyzed material. Thanks to this, it was possible to obtain five mixtures on which the compressive strength tests and petrographic analyses were carried out.To prepare the concrete, the compressive strength class had to first be chosen from which the minimum w/c ratio to use was deduced. Then the optimal particle size curve was determined, obtained using a predetermined theoretical curve as a reference (Bolomey’s curve) ,44.3 . Anothe104:2016  , which consists of the measurement of the fall of a fresh concrete cone suitably formed inside a conical mold with standardized dimensions [For each mixture obtained, the workability measurement was immediately carried out through the mensions . The conmensions . A consiFirst, the results obtained for the single aggregates are shown, then for the created mixtures.Various properties of the concrete depend on the particle size distribution of the aggregate and in particular its workability, that is, the ability to be mixed, installed and processed. A mixture of only a coarse aggregate would be difficult to work because the lack of fine particles inhibits the flow of an inert material on the other; in addition, a mixture without internal adhesion and therefore inconsistent and easily disintegrated would be created. On the other hand, a mixture with abundant fine particles prefers a lot of water to be able to overcome the internal resistance due to the increase in the surface of the particles. Finally, an optimal particle size distribution resulting from the correct calibration of percentages of the different sizes available is the best way to achieve the desired workability and resistance characteristics .The crushed-stone aggregates of fine grain size are in all three cases characterized by higher values than the respective coarser fractions, and this could be explained by the crushing process, which in the smallest elements tends to form splinters that are difficult to work due to their minute size ,53.From the analysis of the results of the sand samples, however, the presence of a low and non-reactive percentage of very fine materials was observed  . Based oThe MB value was determined according to the operating procedure of the methylene blue test  for the Knowing the bulk density and the water absorption value is important to better create the mixtures. High water absorption generally requires more water in the mixture to make up for that which is lost within the porosity of the grains and therefore not directly used by the cement during the hydration reaction ,57. ThisThe Los Angeles values , wear-reFrom the observation of the Los Angeles coefficient (LA) reported in In This test is essential for artifacts that will undergo wear and tear lasting over time such as road surfaces, but it was deliberately considered in this work as a valid support to the proposed studies.Calcareous aggregates. The predominant carbonate lithology of these aggregates is confirmed, and it reflects the supply basin of the Treviso epiclastic conglomerates from which these aggregates came. In fact, clasts of carbonate sedimentary rocks of marine origin predominate . There aMetamorphic aggregates. From the analysis of both gravels and inert aggregates produced by the artificial crushing of the gravels, the clear silicate composition can be seen, above all attributable to paragenesis of clear metamorphic development but with the subordinate presence of intrusive magmatic paragenesis. Also in this case, the analyses support the origin of the alluvial conglomerate and the possible supply basin from which the aggregate samples came . The obsPorphyry aggregates. The porphyritic aggregates of effusive rock of the Atesina porphyritic platform are made up of phenocrysts immersed in a microcrystalline groundmass . AbundanAs noted in the previous section, between the three lithologies chosen, there are differences in the physical-mechanical characteristics as well as the petrographic ones. In addition, for the same lithology, a concrete mixture can vary if rounded aggregates of gravel or polyhedral aggregates of stone are used. The highlighting of these different characteristics can be tackled by considering the packaging of standard mixtures with many w/c ratios and particle size distributions but varying in each of them the lithology and the geometric shape of the coarse fraction.For each type of mixture, the grain size distribution is similar to the Bolomey’s curve  and simi3). The bulk density value obtained for all the mixtures is generally higher than that in other research works [For each mixture, the bulk density was determined through a measurement of the weight of a fresh concrete sample suitably packaged in special molds . The resch works ,68.2. Ten cubes were packaged for each concrete mixture in order to obtain a number of data that would allow obtaining a correct representative average.The fresh concrete samples, in the form of cubes, were subsequently matured in immersion in water at 20 °C for 28 days as required by the UNI EN 12390-3:2019  and subs2 imposed by the UNI EN 11104:2016 [28 in 28 values remain more or less constant for all ten concrete cubes. In this case, the values are similar to those in other scientific works [104:2016 . Furtheric works .The compressive strength test was followed by macroscopic observation of the concrete samples. These samples were obtained by prolonging the crushing phase induced by the press and which therefore allowed the analyzed cubes to be partially crushed. Some representative elements were extrapolated for each packaged mixture, and the main macroscopically observable characteristics were compared.From the first analysis, a substantial difference is observed between the fracturing that occurred on cubes with round aggregates compared to that on cubes with crushed aggregates. The observation of the fragments shows that the detachment between cement paste and aggregate seems to be facilitated in the fragments packaged with round aggregates (gravel). This could be supported by the presence of frequent concave impressions that represent the negative mold of the aggregate itself. It therefore appears to be a detachment facilitated by the shape of the aggregate and is observed in both lithologies with rounded aggregates a,b.On the other hand, in the fragments deriving from cubes packed with crushed aggregates, no evidence of detachment-impression surfaces is observed as in those with rounded aggregates c–e. ThesThe detailed analysis of the thin section allowed us to focus on the aggregate/cement paste contact edges and to recognize some distinctive features that characterize the fragments with rounded aggregates and fragments with crushed aggregates . There iOn the other hand, the fragments with crushed aggregates have a greater paste/aggregate compenetration. This apparent interrelation between the two components is seen above all on the fragments with porphyry aggregate. In fact, in From the comparison of the photo images in The final comparison of the data obtained made it possible to identify some mixtures of aggregates that could provide good physical-mechanical and lithological characteristics to concrete.2, between calcareous and porphyry, but which are still significant since all the mixtures were prepared with the same parameters .The analysis of the average compressive strengths reported in A possible correlation between compressive strength results and the Los Angeles values was therefore analyzed. The Los Angeles test is a mechanical test that could provide information on the intimate resistance of the aggregates subjected to crushing . As can 28 higher than the corresponding rounded aggregates [The graph in gregates . In thisgregates , with coTo support this, the VL values proposed in 28 values for each type of mixture. In addition, the range of variability is observed, that is, the numerical interval within which all the data obtained are found, between the maximum and minimum resistance values. As can be seen, there is a greater range of variability for mixtures made with calcareous lithologies (both rounded gravels and crushed stones) and for porphyry while lower values for mixtures made with metamorphic aggregates. In any case, all the ranges of variability are restricted probably due to the fact that the samples have comparable mechanical strengths. However, it is important to consider that the presence of a range of variability is physiological and probably caused by the package of the cubes [he cubes .The standard deviation represents the average distance of the data from their mean value. This statistical data confirm the goodness of the average obtained. It is possible to obtain two equal averages from different concentrated data: the best data distribution is the one with the smallest standard deviation, which means that the values are not so different from their average. The standard deviation values shown in Another parameter to determine the correct distribution of the data is the variation coefficient, expressed as a percentage ratio between the standard deviation and the average of the measurements. Low coefficient-of-variation values indicate that the concrete cubes were packaged with accuracy . Low coeThe graph in From all this information, it can be said that the resistance data obtained are well concentrated around the representative average value for each concrete mixture and also confirm the optimal packaging of the samples .This research work was focused on the petrographical and physical-mechanical characterization of three natural aggregates, lithologically very different from each other.Experimental research presented included testing of petrographic properties of natural aggregates and demonstrating the relevance of their characterization in the concrete mixture.The morphology of the aggregate clasts is important in conferring mechanical strength to the concrete, and consequently, the type and shape of the chosen lithology become a fundamental factor. This research work showed that mixtures with crushed aggregates have higher mechanical strength than mixtures with round aggregates. Unfortunately, however, the vast majority of Italian concrete mixing plants use rounded aggregates since most of the aggregate quarries are made up of alluvial sedimentary deposits characterized by gravels. In addition, the costs for crushing the extracted rounded alluvial material would be minor and not very advantageous.The physical-mechanical data indicated good results of the porphyry aggregate with respect to the other lithologies. Furthermore, it seems that better mechanical characteristics can be obtained by the crushed aggregates thanks to their rough surface. These conclusions are valid for the w/c ratio used, for the lithologies compared and for the maturation of the concrete cubes for 28 days. Despite this, the porphyry aggregate consists of a vitreous silicate component that over time can probably degrade the durability of the concrete through chemical reactions such as alkali–silica, which are particularly harmful.2 imposed by the UNI EN 11104:2016. Furthermore, a substantial growth trend was observed, passing from calcareous to metamorphic and porphyritic lithology.As concerns the compressive strength values of each mixture, it was observed that all the breaking values exceeded the minimum resistance limit of 30 N/mmTo better characterized this, further analyses are needed especially of blends packaged with different w/c ratios. It is, in fact, possible to foresee that this difference is no longer observable for high-performance concrete mixtures, with low w/c ratios and high mechanical strengths, since the cement present in considerable quantities could reduce the effects due to the petrographic composition and the form factor of the aggregates used for the mixture. In addition, it is necessary to observe the trend of the data also for maturation of the concrete cube for more than 28 days imposed by the legislation to verify that the alkali–silica reactions cannot arise with the vitreous paste of the porphyry aggregates.Another important aspect is the necessary use of higher water contents, with the same consistency class, with a crushed aggregate compared to a rounded aggregate. This increase in water is necessary by the lower smoothness of the crushed surfaces which, being rougher, make the concrete more viscous. It is therefore deduced that crushed aggregates offer greater resistance to flow than those with rounded aggregates. This would not be a problem if there was not a consequent increase in the cement content needed to maintain the required w/c ratio, but this would mean an increase in the final cost of the mixture, largely due to the cost of this component. This would produce an uneconomical and unsaleable concrete. It should also be remembered that a concrete that is easily workable is preferred, a characteristic guaranteed by the right w/c ratio and, in addition to the additives, by the use of an alluvial aggregate with smooth surfaces. The minimum limits in the dosages of cement and w/c ratios imposed by the UNI EN standards for the packaging of a specific type of concrete, however, ensure the achievement of the mechanical resistances, and therefore it is not necessary to use aggregates with characteristics such as the surface macro roughness of the porphyry.Ultimately it is always necessary to find the right way to relate experimental deductions deriving from studies such as the one proposed and the real practical needs imposed by the world of work, with a focus on the economic factor of the entire production process.


Guest molecular features determining the formation of α and β phases of poly oxide (PPO) are explored by collecting literature data and adding many new film preparations, both by solution casting and by guest sorption in amorphous films. Independently of the considered preparation method, the α-form is favored by the hydrophobic and bulky guest molecules, while the hydrophilic and small guest molecules favor the β-form. Furthermore, molecular modeling studies indicate that the β-form inducer guests establish stronger dispersive interactions with the PPO units than the α-form inducer guests. Thus, the achievement of co-crystalline  α- and β-forms would result from differences in energy gain due to the host–guest interactions established at the local scale. An engineering thermoplastic polymer, poly oxide (PPO), is always amorphous by melt processing , while iIn particular, two completely different classes of co-crystalline (CC) forms with low-molecular-mass guest molecules can be obtained. The CC forms of Class i are formed only with a few specific guests , exhibit regular polymer helices, and give rise to highly ordered crystalline phases . The CC c = 0.528 nm and c = 0.547 nm) and different polymer packing  (The CC forms of Class ii can be divided into two subclasses (α and β) with different values of the chain periodicities  .Both the CC α- and β-forms can be obtained by guest-induced crystallization of amorphous samples or solution processing. However, in previous studies, we have found that most guest molecules give only CC α-form or CC β-form, independently of the crystallization procedure, and, as a consequence, have been named α or β guests of PPO.3, respectively, being much lower than that of the corresponding amorphous phase (1.04 g/cm3)  .A study on the stability of the NC α- and β-forms to the uptake of β and α guests, respectively, has shown that the NC α phases by sorption of a β guest lead to CC α phases, while on the contrary, the NC β phases by sorption of an α guest can lead to CC α phases . This clAlong with another commercial thermoplastic polymer  , PPO is The present study collects literature data as well as new data relative to the influence of the chemical nature of the guest on the formation of CC and NC α or β phases of PPO. PPO crystallization is conducted by two different routes: solution casting and guest-induced crystallization of amorphous films. The aim is to try to establish, with the support of molecular modeling, guest molecular features determining the formation of α or β crystalline phases.w = 350 kg/mol, P6130 grade) of PPO was kindly supplied by SABIC, Milan. The following compounds: acetonitrile, p-xylene, 1,3-dichlorobenzene, perchloroethylene, m-xylene, ethylbenzene, 1,2-dichloropropane, 1,4-dioxane, ethyl acetate, diethyl ether, and tetrahydrofuran were purchased from Aldrich and used without further purification.An ultrahigh molecular weight  was conducted with a Vertex 70 Bruker spectrophotometer. It is equipped with a deuterated triglycine sulfate detector and a Ge/KBr beam splitter, which are operated at 2.0 cmδsp)   and soluδsp) , were coA is the Avogadro’s number (6.02 × 1023 molecules/mol).The guest molecular volume was calculated from the following equation :Vguest=We carried out the density functional theory static calculations with the Gaussian 09, Revision E.01 set of programs . We adopp-xylene (A) and 1,3-dichlorobenzene (B) exhibit hk0 diffraction peaks at 2θCuKα ≈ 7.1°, 11.3°, 15.0° typical of the α-form, while the crystalline phases obtained with perchloroethylene (D), ethylbenzene (E), 1,2-dichloropropane (F), and 1,4-dioxane (G) exhibit the hk0 diffraction peaks at 2θCuKα ≈ 7.7°, 12.8° typical of the β-form. The WAXD pattern of the film obtained by casting from m-xylene solution (C) shows diffraction peaks of both α and β crystalline forms.WAXD patterns of the NC PPO films (with thickness in the range 40–70 µm), as obtained by casting from 1.5 wt% polymer solutions in many different solvents, followed by guest removal by immersion in acetonitrile for 2 hours, are shown in −1. In fact, −1), while the spectra of −1).This information is confirmed by FTIR spectra of the same films of The crystalline forms (α or β) of films as crystallized by sorption of the same solvents in amorphous PPO films were also established by WAXD and FTIR measurements, like those of This fourth column of Based on the crystallization data of 3 and lower than 149 Å3 lead to the α- and β-forms, respectively. As for the guest molecular volume, it is worth adding that it also has a key role in determining the orientation    of PPO fm plane) . Table 3In summary, our data in The molecular modeling of the following section is aimed to rationalize the presently observed behavior.3, as examples of β-form inducer guests, and 1,1,1-trichloroethane (TCA) and CCl4, as examples of α-form inducer guests. For the sake of simplicity, the conformation of the model dimer was assumed in the extended state as in the repetition unit of the model chain of Supplementary Figure S2C of de-to-e with an increase of τ as reported in Potential energy calculations were performed in the hypothesis that the formation of the α and β CC and NC forms is driven by the host–guest dispersive interactions exerted at the local scale between a PPO monomeric unit and a guest molecule. In particular, the potential energy was calculated on the methyl-terminated model dimer of PPO as shown in Eg and Ed-st, respectively. The values of the minimum potential energy relative to the model dimer, after subtraction for the corresponding absolute minimum, are reported in In the first step, calculations were performed on the isolated guest, and the isolated model dimer as a function of τ, to find the corresponding minimum potential energy g (g standing for guest) pointing perpendicular to the plane of the phenyl ring in front of the corresponding center of mass cm1 , while treating the model dimer and the guest in low-energy conformations as rigid bodies. In practice, the guest was initially positioned with the center of mass cmmass cm1  and/or pssing Oc . The spag, and the rotations around its principal axes, while fixing the value of τ. Thus, the identified minima were approached starting from different initial configurations, making our simple approach quite reliable.In the third and last step, the potential energy profiles were calculated starting from the identified low-energy configurations while minimizing the energy with respect to the internal coordinates of the guest, the position of its center of mass cmE) is shown as a function of τ. For each value of τ, the energy gain (ΔE) was calculated as the difference between the energy of the adduct with the stretched PPO model dimer Ea-st and the sum (Eg + Ed-st), that is, ΔE = Eg-st − (Ea + Ed-st). Therefore, the values of ΔE account exclusively for the dispersive energies established at the host–guest interface. The negative values of ΔE at a given τ value entail that the given conformation is stabilized by the guest. Notice that the lower the ΔE, the higher the stabilization effect.In ΔE values). In particular, the β-form guest inducers DCA and CHCl3 produce a neat decrease of the potential energy by 6.5–7.5 kcal/mol, whereas the α-form guest inducers TCA and CCl4 produce a lower decrease of potential energy that amounts to 5–6 kcal/mol. Furthermore, whereas DCA and TCA tend to stabilize the stretched PPO conformations the higher, the greater the τ value, the potential energy stabilization tends to decrease for the ball-like molecules CCl4 and CHCl3 with increasing τ. Therefore, although kinetic aspects of the guest-induced crystallization of PPO in the α- and β-forms come certainly into play, according to 3 guest molecules, regardless of the stretching state of the model dimer.It is apparent that by the effect of the presence of the guest molecules, a neat gain of potential energy is achieved, regardless of the τ value and guest type  .The low-energy configurations of the host–guest adducts obtained from calculations for the α- and β-form inducers are shown in 3 and DCA show a preferential interaction between a hydrogen atom and the center of the phenyl ring of the PPO dimer, while the α-forms guest inducers CCl4 and TCA preferentially interact via a chlorine atom with the center of the phenyl ring. Such a kind of interaction between a halogen atom and a phenyl ring has already been reported , the host-guest center-to-center distance (dCM1-guest), the guest molecular volume, and the water solubility of the guests. These parameters’ lowest and highest values were scaled to 100 and 0%, respectively, for ΔE and dCM1-guest, and to 0 and 100%, respectively, for the molecular volume and water solubility.In 3. The less hydrophilic guest molecules TCA and CCl4 that possess a higher molecular volume, instead,  to evaluate the influence of the chemical nature of the guest on the formation of α or β phases.3 and lower than 149 Å3 lead to the α- and β-forms, respectively. Moreover, all guests with solubility lower than 0.11 mmol per 100 ml of water and higher than 2 mmol per 100 ml of water lead to the α- and β-forms, respectively.The present analysis shows that independently of the two considered crystallization methods, the α-form is favored by hydrophobic and bulky guest molecules while the β-form (being characterized by a higher chain periodicity) is favored by hydrophilic and small guest molecules. In detail, all the considered guests with molecular volumes higher than 230 ÅAccording to our molecular modeling study on two α-form inducer guests and on two β-form inducer guests, the latter would establish stronger dispersive interactions with the polymer chain than the α-form inducers. Therefore, the achievement of CC (and derived NC) β-forms would result from the high energy gain achieved by the adduct, and the short center-to-center distance established at host-guest interfaces.


Immunoglobulin G4-related disease (IgG4-RD) can affect various organs, including the cardiovascular system. In this study, we described the case of a 72-year-old man with periaortitis both in the ascending and terminal aorta related to IgG4-RD. He presented with swelling in the left leg. Computed tomography (CT) showed increased wall thickness of the ascending aorta and retroperitoneal fibrosis, which, in turn, caused deep vein thrombosis. Using positron emission tomography-computed tomography, the patient was diagnosed with IgG4-RD in the aorta. Although it was difficult to distinguish intramural hematoma (IMH) from IgG4-related periaortitis, treatment with steroids has dramatically improved his periaortitis. IgG4-related periaortitis should be differentiated from IMH due to their similar morphologies. Several reported cases of retroperitoneal fibrosis (RF) associated with IgG4-RD responded dramatically to steroid therapy. IgG4-RD can affect any organ in the body, and IgG4-RD in the cardiovascular system has been previously reported. However, there are very few reports of IgG4-related periaortitis mimicking an intramural hematoma (IMH). These two conditions present with radiologic similarities, leading to misdiagnosis and treatment. Herein, we describe the case of IgG4-related periaortitis in the ascending aorta with RF and the development of acute deep vein thrombosis (DVT).Immunoglobulin G4-related disease (IgG4-RD) is defined as a systemic inflammatory disease characterized by elevated serum levels of IgG4, infiltration of IgG4-positive lymphocytes, and storiform fibrosis. The patient was prescribed 30 mg/day prednisolone (0.34 mg/kg/day) for 4 weeks. After that, the dosage was gradually reduced. The left lower extremity diameter, CRP, and serum IgG4 were noted to improve after the start of prednisolone. The left iliac vein with enhanced uptake of 18F-FDG was shrunk, and thrombi remained despite anticoagulant therapy (A 72-year-old man with a history of RF presented with swelling and pain of the left lower extremity. The symptoms were attributed to acute DVT diagnosed by magnetic resonance angiography (MRA), which showed occlusion of the left iliac vein ( In terms of IgG4-related aortitis, diagnostic certainty is difficult in many cases due to its radiologic similarities between aortitis, IMH, and aortic dissection. Thus, IgG4-related aortitis can be confused with these acute aortic diseases using CT imaging in emergency situations due to the increased aortic wall thickness. In this present case, emergency surgery to address the findings of the ascending aorta was avoided because of the possibility of vasculitis based on the development of RF and acute DVT. As a result, medications, including steroid therapy, have remarkably improved the aortic abnormalities and retroperitoneal lesions. Thrombolysis was limited to treating the DVT; however, the improvement of RF may have contributed to the improvement of edema in the left lower extremity.IgG4-RD was first recognized in autoimmune pancreatitis in 2001, and IgG4-related vascular disease was first reported in 2008. In two case reports, a thoracotomy was performed for IgG4-related aortitis because differentiation could not be preoperatively performed. In this case, thrombolysis could have been used to manage acute DVT; however, this approach would have been contraindicated for IMH. Therefore, using the least necessary intervention and managing the case with anticoagulant therapy alone might be considered a safer strategy. To address this diagnostic hurdle, MRI can quickly distinguish between IgG4-related aortitis and IMH in an emergency room, as shown in The differential diagnosis between IMH and IgG4-related aortitis has been identified of great importance since the treatments differ significantly in terms of their invasiveness; IgG4-RD can be treated with medication, whereas treatment of IMH in the ascending aorta requires a thoracotomy. Although IMH is much less common than acute aortic dissection, they have similar mortality rates. However, obtaining a cardiovascular biopsy remains difficult and is deemed high risk; thus, a cardiovascular biopsy cannot always be obtained. Therefore, FDG PET-CT is useful for the diagnosis and evaluation of disease activity. In addition, FDG PET-CT may indicate other biopsy sites for diagnosis. In the case of our patient, serum IgG4 was elevated, and a remarkable accumulation of FDG was observed around the ascending aorta by PET-CT. Disease activity was also confirmed in RF and the left iliac vein. Disease activity was especially evidenced by the thrombosis formation in the left iliac vein, which could be associated with vasculitis, as shown in IgG4-related vasculitis has no specific diagnostic criteria; it is diagnosed with the same diagnostic criteria as normal IgG4-RD. A definitive diagnosis requires tissue obtained by biopsy or surgery. The typical pathologic features include adventitial inflammation, fibrous thickening, and lymphoplasmacytic infiltration. However, in one case, rapid aortic wall thinning after steroid therapy caused the rupture of an aortic aneurysm. Thus, patients treated with steroid therapy for suspected IgG4-related aortitis should be followed up due to the possibility of aortic aneurysm formation with steroid treatment.Steroid therapy has been well recognized as the first-line therapy for IgG4-RD. Mizushima demonstrated that perivascular lesions of periaortitis improved with steroid therapy, and changes in serum IgG4 levels after steroid administration reflect the therapeutic effect.In this study, we presented the case of IgG4-related aortitis in the ascending aorta with RF and acute iliac vein occlusion. IgG4-related aortitis has been noted to have radiologic similarities to acute aortic diseases, such as aortic dissection and IMH. Treatment plans differ widely for patients according to the diagnosis, and we should keep this fact in mind.


The paper is intended to provide scientists, civil engineers, and designers with guidelines for examining and assessing the long-term durability of old concrete, and also extending knowledge in the field of archaeological restoration and the protection of old concrete structures.This research aims to determine the mechanical, chemical, and physical properties of old concrete used in the former Leipziger Palace in Wrocław, Poland. The cylindrical specimens were taken from the basement concrete walls using a concrete core borehole diamond drill machine. The determination of the durability and strength of old concrete was based on specified chosen properties of the old concrete obtained through the following set of tests: measurements of dry density, tests of water absorption, specification of concrete compressive strength and frost resistance, determination of the modulus of elasticity, measurement of the pH value, determination of water-soluble chloride salts and sulphate ions, and X-ray diffraction analyses. Large dispersions of the compressive strength (10.4 MPa to 34.2 MPa), density (2049 kg/m Concrete and reinforcement concrete were invented in the second half of the 19th century, and developed new possibilities to create new constructions and extended knowledge in civil and building engineering . The losThe present investigation of old concrete is related to a former palace building, called Leipziger Palace. The former Leipziger Palace in Wrocław (Poland) was built on the site of a riding school, from 1872 to 1874, by the banker Ignacy (Ignatz) Leipziger. The palace was designed by the famous architect Carl Schmidt (1835–1888), who was the designer of buildings important to Wrocław , includiThis paper contains investigations on old concrete basement walls for which determinations of the durability and concrete strength based on the chosen mechanical, chemical, and physical properties were carried out. The concrete basement walls were 120 ÷ 140-year-old structural concrete elements. The investigation program consisted of the following sets of laboratory tests: measurements of dry density, tests of water absorption, specification of concrete compressive strength, specification of frost resistance, determination of modulus of elasticity, measurement of the pH value, determination of water-soluble chloride and sulphate ions, and carrying out X-ray diffraction analyses. It should be noted, that the available tools and laboratory equipment used to perform the present investigation were used in previous laboratory tests on old concretes performed by the authors ,33. The fc,cycl 100) and a length to core diameter ratio of 1 were used for compressive tests. The dimensions of the concrete cores were specified according to the standard EN 12504-1 [fc,cycl 100 can be directly comparable to the cube strength fc,cube of 15 cm × 15 cm × 15 cm concrete specimens. Secondly, six concrete cores with a length to core diameter ratio equal to 1.5 and 2.0 with a diameter of approximately 100 mm were prepared to determine the modulus of elasticity indicated by two chosen standards. The EN 12390-13 [The old concrete specimens for the determination of the mechanical, chemical, and physical properties were taken from the structural elements of basement walls by a concrete core borehole diamond drill machine see a. It can 12504-1 . The str12390-13  standard12390-13  requires12390-13 .The density of the old concrete was specified according to the method given in the EN 12390-7 standard . Before EN 13369 standard  was applThe Advantest 9 C300KN computer-controlled mechanical testing machine was used to perform uniaxial compressive experimental tests on the old concrete cylinder specimens. The EN 12390-3 standard  guidelinThe concrete specimens were subjected to 50 freezer cycles in a freezing chamber with a temperature- and time-controlled refrigerating and heating system according to the PN-B-06250 standard  for the EC,S in the range of 33% ultimate strength of concrete for old core samples with a length to diameter ratio equal to 2.0. The 30% of the ultimate strength is required in ISO 1920-10 [Determination of the secant elasticity modulus in the compression was performed using the guidelines of two standards: EN 12390-13  and ASTM 1920-10  for the  1920-10  standard 1920-10 , like EN 1920-10 , needs 4The ISO 10523  standard−) and sulfate ions (SO42−). The Volhard method was used for the determination of the chloride ions. Like in the pH measurement, the old concrete samples were crushed, dissolved in distilled water, and filtrated through a mixed cellulose ester membrane filter with a pore size of 45 μm before the measurements of the water-soluble chloride ions (Cl−) and sulfate ions (SO42−) were carried out.The EN 1744-1 + A1 standard  was applThe morphology of the old concrete samples was performed using a scanning electron microscope  equipped with an energy dispersive X-ray spectrometer , which allowed for the identification of the elemental composition of the tested material. The accelerating voltage was 15 kV. The results of the analysis were documented with the image (SEM), the graphical representation of the reflection peaks (EDX), and the chemical composition table.−1. The study sample was grounded in an agate mortar until the whole sample passed through a 63 um sieve. PDXL software was used to process the diffraction data.The mineralogical composition of the concrete samples was determined by the X-ray diffractometer . A copper tube (CuKα = 1.54178 Å) was used as the source of the X-ray emissions. The tests were carried out under the operating conditions of the device: 40 kV and 15 mA, 5–90 ◦2θ range, with a scanning rate of 5°·min3 to 2205 kg/m3 . However, the mean dry density of the old concrete specimens are below the 2160 kg/m3 limit specified in the ACI 318-19 standard [The laboratory tests showed that the dry density of the old concrete varied from 2049 kg/mg/m3 see . The meao EN 206   of 8 MPa (N/mm2) and cube strength  of 10 MPa.Finally, it is possible to determine the characteristic in-situ compressive cube strength EN 13791  standardo EN 206  is estimstandard , should Cylindrical samples were subjected to 50 freezer cycles consisting of freezing at −18 ± 2 °C for 4 h and thawing by total immersion in water at 18 ± 2 °C for 4 h. After 50 freezer cycles see a, the coples see a. The diEC,S, specified according to EN 12390-13 [E0.0–0.4 and E0.1–0.3 was observed. The mean modulus of elasticity for E0.0–0.4 was 12.17 GPa and for E0.1–0.3 was 14.97 GPa.The stabilized secant modulus of elasticity, 12390-13 , ranged 12390-13 , the mod2) and greater or equal to 13.73 MPa (140 kg/cm2), the modulus of elasticity corresponds values of 9810 MPa  and 14,715 MPa , respectively. For the specified characteristic in-situ cube compressive strength equal to 11.4 MPa, the modulus of elasticity corresponded to a value 11.8 GPa, according to guidelines [The present EN 1992-2 standard  states tThe pH value is an important factor that influences the corrosion rate of reinforcement ,76. Fres−) and sulfate ions (SO42−) was determined as the percentage of dry weight using the chemical tests. The water-soluble chloride ion values ranged from 0.028 % to 0.108 %  arete mix , and therete mix ). Based The scanning electron microscopy (SEM) image of the chosen sample taken from the old concrete structure is shown in The presented image SEM see a of the The XRD method was applied for the identification of the phase composition of the old concrete. The results of the mineralogical composition (in the form of a diffraction pattern) based on a chosen old concrete sample are presented in 0,32 (Si4O10) (OH)2xnH2O–montmorillonite, calcium–magnesium–aluminium–silicate hydrate (C-M-A-S-H), CaCO3  as the carbonate phase, Ca(OH)2–portlandite, and SiO2–quartz. The registered chemical compounds are products of the reacted clinker phases included in the cement used for concrete, including many years of exposure to atmospheric conditions and water.The analysis of the evolution of concrete over the years, its phase composition, and its microstructure is critical to determine its durability. The obtained test results see  indicate3S or C2S), but also from other soluble siliceous materials that may be present in the cement. In the investigated old concrete samples, the calcium silicate was combined with aluminium and magnesium ions. The present form is the result of long-term environmental influences. The crystalline CaCO3 is the result of the reaction of atmospheric carbon dioxide with the mineral components of the cement. With CO2 entering the concrete for many years, carbonation reactions can produce one or more reaction fronts that progressively move through the concrete structure. The resulting carbonation products influence the porosity/permeability of concrete. The inward diffusion of carbonate ions forms calcite, which stabilizes the paste and develops a carbonate-stabilized shell. The presence of a chemical that forms complex compounds that include calcium, magnesium, and aluminium ions may result from the hydration process of the cement used for concrete, or it may be the result of the influence of a corrosive environment on the structural concrete for 120 to 140 years.The calcium–silicate–hydrate (C-S-H) is the most important of the hydration phases of cement. C-S-H precipitates from the ions produced in the pore solution through the dissolution of anhydrous calcium silicates , and Ca(OH)2–portlandite.The chemical composition (SEM/EDS) and X-ray composition (XRD) indicated the domination of certain compounds in the old concrete structure, such as calcium-magnesium–aluminium–silicate hydrate (C-M-A-S-H), CaCOThe old concrete had a layer structure formed from the products of the cement hydration process.The registered chemical compounds were the products of the reacted clinker phases included in the cement used for concrete, including many years of exposure to the atmospheric conditions and water.The old concrete did not meet most of the current standard requirements see , neverthThis paper focuses mainly on the characterization of old concrete samples from a historical building. The mechanical, chemical, and physical properties of old concrete built in the former Leipziger Palace in Wrocław, Poland, were specified through laboratory tests. The investigation found the following conclusions:This paper determined the properties of old concrete built in the former Leipziger Palace nearly 120 to 140 years ago. Determination of the mechanical, chemical, and physical properties of old concrete makes it possible for proper future investigations on planning for the condition assessment of old concrete constructions. The authors are hopeful that the present investigation sparks interest among a wide group of engineers, archaeologists, and scientists on the subject of old concrete. This investigation may also be treated as motivation for new investigations on old concrete structures.


It was found that 1 showed pH-dependent guest-binding behavior. That is, 1 strongly bound an anionic guest, 6-p-toluidinonaphthalene-2-sulfonate (TNS) with binding constant (K/M−1) for 1:1 host-guest complexes of 9.6 × 104 M−1 at pH 3.8, which was larger than those at pH 7.4 and 10.7 , indicating a favorable electrostatic interaction between anionic guest and net cationic 1. What is more, release of the entrapped guest molecules by 1 was easily controlled by pH stimulus. Large favorable enthalpies (ΔH) for formation of host-guest complexes were obtained under the pH conditions employed, suggesting that electrostatic interaction between anionic TNS and 1 was the most important driving force for host-guest complexation. Such contributions of ΔH for formation of host-guest complexes decreased along with increased pH values from acidic to basic solutions. Upon addition of dithiothreitol (DTT) as a reducing reagent to an aqueous PBS buffer (pH 7.4) containing 1 and TNS, the fluorescence intensity originating from the bound guest molecules decreased gradually. A treatment of 1 with DTT gave 2, having less guest-binding affinity by the cleavage of disulfide bonds of 1. Consequently, almost all entrapped guest molecules by 1 were released from the host. Moreover, such reduction-responsive cleavage of 1 and release of bound guest molecules was performed more rapidly in aqueous buffer at pH 10.7.A water-soluble cyclophane dimer having two disulfide groups as a reduction-responsive cleavable bond as well as several acidic and basic functional groups as a pH-responsive ionizable group  Synthetic macrocyclic hosts play a crucial role in supramolecular chemistry and nanoscience ,2,3,4. C1 . In addition, we demonstrated pH-dependent guest-binding behavior and reduction-responsive cleavage of 1, with a concomitant enhanced release of bound guest molecules.Among these hosts, azacyclophanes have an advantage from the view point of their modifications by attaching various functional moieties on the nitrogen atoms of the macrocyclic skeleton ,31,32. O1 . The forbilities . Host 1 1  of 1 was synthesized by aminolysis of 4 with EDTAD. A treatment with trifluoroacetic acid (TFA) gave water-soluble cyclophane dimer 1 from 5 by removal of the protecting groups in a fairly good yield. All the new obtained compounds were fully assigned by 1H and 13C NMR spectroscopy, matrix-assisted laser desorption time of flight mass spectrometry (MALDI-TOF MS), and elemental analysis  as an anionic fluorescent guest, whose emission is extremely sensitive in the intensity to change in microenvironmental polarity surrounded by the molecule, was examined by fluorescence titration experiments at 298 K. First, we executed the fluorescence titration experiments of 1 with TNS at three pH levels: 3.8 (acidic), 7.4 , and 10.7 (basic). Upon addition of 1 in a large excess amount to each of the aqueous buffers containing TNS, the fluorescence intensity originated from the entrapped guest increased, showing saturation behavior, as shown in 1 increased in the following sequence of pH: 3.8 > 7.4 > 10.7 (K/M−1) for 1:1 host-guest complexes was calculated on the basis of the Benesi–Hildebrand method +, where M stands for the corresponding thiol of cyclophane, C49H64N8O5S  containing 1 and TNS at 298 K, the fluorescence intensity originating from the bound guest molecules decreased gradually, as shown in 1 with DTT gave 2 with less guest-binding affinity by the cleavage of disulfide bonds of 1. Accordingly, almost all entrapped guest molecules by 1 were released to the bulk aqueous phase. Moreover, reduction-responsive cleavage of 1, accompanying the release of entrapped guest molecules, was performed more rapidly in aqueous buffer at pH 10.7, as shown in 1 with TNS, the fluorescence intensity decreased, indicating the release of the entrapped guest molecules  was prepared according to the literature reported previously ethanesulfonic acid (HEPES) buffer (pH 7.4), and carbonate buffer (pH 10.7) were used for fluorescence experiments.Succinimidyl ester derivative of tetraaza[6.1.6.1]paracyclophane bearing Boc-protected β-alanine residues (eviously . 6-p-tol3) +, where M shows C66H93N9O11S2.A solution of succinimidyl ester derivative of cyclophane (3)   in dry N, N-dimethylformamide , and the resulting mixture was stirred for 5 days at 60 °C. Chloroform (100 mL) was added to the residue, and the mixture was then washed with saturated aqueous sodium chloride (20 mL). After being dried (Na2SO4), the solution was evaporated to dryness under reduced pressure to give a white solid. The crude product was purified on a column of Sephadex LH-20 (methanol) as an eluent for purification. Evaporation of the main fraction on a rotatory evaporator gave a white solid . Subsequently, trifluoroacetic acid (1.3 mL) was added to a solution of 5  in dry DCM (4 mL), and the mixture was stirred for 3 h at room temperature. Evaporation of the solvent under reduced pressure gave a white solid. The crude product was purified on a column of Sephadex LH-20 (methanol) as an eluant. The product fraction was evaporated and dried in vacio to give a white solid. : 1H NMR  δ 1.44 , 2.05 , 2.15 , 2.35 , 2.44 , 2.82 , 2.89 , 3.07 , 3.12 , 3.20 , 3.45 , 3.58 , 3.69 , 4.04 , 6.92 , 7.18 , and 7.40 . 13C NMR  δ 22.3, 22.4, 25.6, 28.7, 31.0, 34.5, 35.7, 40.3, 42.0, 47.6, 55.1, 121.8, 128.2, 130.2, 139.4, 141.5, 160.1, and 170.1. Found: C, 49.32; H, 6.16; N, 9.38. Calcd for C124H156F18N20O28S4•10H2O: C, 49.23; H, 5.86; N, 9.26. MALDI-TOF MS: m/z 2162.3 [M + H]+ and 2184.3 [M + Na]+, where M denotes cyclophane derivative as a free base and carboxylic acid (C112H150N20O16S4).Ethylenediaminetetraacetic dianhydride  was added to a solution of 1, and the fluorescence intensity originating fron the guest was monitored after each addition. The K values were calculated by using the Benesi–Hildebrand method for titration data.To each solution of TNS (1.0 μM), HEPES buffer  were added increasing amounts of Elemental analyses were measured using an elemental analyzer J-Science Lab JM11 . Fluorescence spectra, IR spectra, MALDI-TOF MS, and NMR spectra were recorded on a JASCO FP-750 , Perkin-Elmer spectrum one spectrometer , Bruker autoflex speed , and Bruker Avance III 400 , respectively.1. Host 1 was found to show pH-dependent guest-binding behavior. The bind and release of TNS as an anionic guest by 1 was easily controlled by pH stimulus. Large favorable ΔH values were obtained under the pH conditions employed, suggesting that electrostatic interaction between anionic TNS and 1 was the most effective driving force for host-guest complexation. In addition, 1 was found to show reduction-responsive guest-binding behavior. Monomeric cyclophane 2 with less guest-binding affinity formed by the cleavage of disulfide bonds of 1 by DTT. Consequently, almost all entrapped guest molecules were released from 1. Moreover, release of entrapped guest molecules proceeded more rapidly through reduction-responsive cleavage of 1 at basic pH. Finally, guest-binding and releasing abilities of 1 are controlled by pH stimulus as well as reducing reagents, such as DTT.We synthesized a water-soluble cyclophane dimer with two disulfide groups as a reduction-responsive cleavable bond as well as several acidic and basic functional groups as a pH-responsive ionizable group


Escherichia coli and Bacillus subtilis as the representative strains of Gram-negative and Gram-positive organisms, respectively. Freshly prepared discs and discs stored in the dark for 7 or 14 days served as our controls. We show that the antibiotic potential of oxytetracycline exposed to sunlight dramatically decreases over the course of 14 days against both E. coli and B. subtilis. However, the effectiveness of streptomycin was only moderately impacted by sunlight. It is important to note that antibiotics that last longer in the environment may play a deleterious role in the rise and spread of antibiotic-resistant bacteria. Further studies are needed to substantively analyze the safety and efficacy of antibiotics used for broader environmental applications.Antibiotic stewardship is of paramount importance to limit the emergence of antibiotic-resistant bacteria in not only hospital settings, but also in animal husbandry, aquaculture, and agricultural sectors. Currently, large quantities of antibiotics are applied to treat agricultural diseases like citrus greening disease (CGD). The two commonly used antibiotics approved for this purpose are streptomycin and oxytetracycline. Although investigations are ongoing to understand how efficient this process is to control the spread of CGD, to our knowledge, there have been no studies that evaluate the effect of environmental factors such as sunlight on the efficacy of the above-mentioned antibiotics. We conducted a simple disc-diffusion assay to study the efficacy of streptomycin and oxytetracycline after exposure to sunlight for 7- or 14-day periods using  Although antibiotics have been used for agricultural purposes for decades, due to the rapid rise in antibiotic resistance this usage needs to be revisited. Questions remain on the appropriate mode of application for antibiotics and the actual benefits of using antibiotics for treating the infections caused by plant pathogens, especially for the ones that are intracellular in nature. Here, we show that the two commonly used commercial antibiotics, oxytetracycline and streptomycin, lose their efficacy at different rates in the presence of sunlight. While the former loses its potency within days, the latter remains active for many days. Thus, oxytetracycline may not be active long enough to produce its desired effect, and streptomycin may persist in the environment and as a side effect due to its selective pressure, may force the rise of streptomycin-resistant pathogens.Candidatus Liberibacter asiaticus (CLas) that is transmitted between plants by certain psyllids, which are sap-feeding insects. CLas is a fastidious, Gram-negative, intracellular plant pathogen that belongs to the phylum of α-proteobacteria  and the freshly prepared discs  showed negligible and maximum zones of inhibition (ZOI), respectively  dissolved in water and placed the antibiotic-laden discs in either a natural outdoor setting with abundant sunlight to simulate agricultural use, or in a dark indoor cabinet for 7 or 14 days. In addition to the discs that were kept in the dark, we also used freshly prepared discs and vehicle (water) discs as controls. The discs were then placed, as shown in ectively . The dissubtilis . This su 14 days . This imE. coli and B. subtilis, respectively, when compared to that of our positive control. Further measurable decrease to nearly 50% efficiency compared to our positive control was noted subsequent to 14 days of sunlight exposure for E. coli. However, the decrease in efficiency for B. subtilis at the 14-day time point was within the standard error when compared to that of the 7-day time point  served as our negative and positive controls, respectively. As expected, the ZOI were unobservable for our blank discs and maximum for our positive controls . Similarme point .E. coli and B. subtilis (see B. subtilis and 10.28 ± 0.26 mm (P) and 10.08 ± 0.48 mm (H) for E. coli. For streptomycin, the ZOI were 10.11 ± 0.49 mm (P) and 10.06 ± 0.39 mm (H) for B. subtilis and 10.56 ± 0.81 mm (P) and 10.44 ± 0.73 mm (H) for E. coli. Based on this data, we infer that UV radiation from sunlight is likely the most dominant cause for the decrease in the antibiotic potential of oxytetracycline.Next, we investigated whether the increase in temperature or UV radiation from sunlight leads to the increased loss of the antibiotic potential of oxytetracycline. For this purpose, we prepared the antibiotic discs containing oxytetracycline or streptomycin as described previously and placed them either (i) in a dark incubator at 37°C; or (ii) in an enclosed dark chamber illuminated with a UV light source at room temperature; for 48 h. Subsequent to this step, these discs and the control discs were subjected to the disc-diffusion assay described previously. As shown in ilis see , 2CC’. QRapid rise of antibiotic resistance in bacteria is a major concern worldwide with enormous predicted fatalities resulting from drug-resistant bacteria causing difficult to treat infections. Antibiotics are now routinely used in clinics, animal husbandry, and agriculture. Acknowledgment of the fact that the rise of antibiotic resistance stemming from one of those settings could potentially render antibiotics useless led to the formation of a multidisciplinary collaborative initiative to promote antibiotic stewardship under the umbrella term One Health . DespiteStreptomyces spp. However, soil bacteria do not produce antibiotics at levels comparable to commercial applications – which can occasionally be in the scale of thousands of kilograms . A 100 μl aliquot of culture was then spread onto LB agar plates using sterile beads and set to dry completely prior to the placement of discs, see section below.The UV sterilized Whatman filter paper discs (7 mm) were impregnated with 5 μl of a freshly made stock antibiotic solution of either 40 mg/ml streptomycin sulfate (MilliporeSigma) in sterile distilled water or 10 mg/ml oxytetracycline hydrochloride (Alfa Aesar) in sterile distilled water to reach a concentration of 200 μg for streptomycin and 50 μg for oxytetracycline in each disc, and then set to dry completely. The concentrations selected were based on the concentration range recommended for agricultural use , and aftGraphPad Prism Software (version 8.3.1) was used to analyze the data. All data represent biological triplicate data with technical replicates. Graphs show mean values and error bars represent standard deviation (SD).The raw data supporting the conclusions of this article will be made available by the authors, without undue reservation.SK and PE: conception and design of the study, and writing of the manuscript. SK and AO: data acquisition. SK, AO, and PE: analysis and/or interpretation of the data. All authors contributed to the article and approved the submitted version.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.