As knowledge of the service lifespan of reinforced concrete is crucial in terms of corrosion, the carbonation process is important to study, and high-performance durable reinforced concretes can be produced to prolong the effects of corrosion. To examine carbonation resistance, accelerated carbonation testing was conducted in accordance with the standards of BS 1881-210:2013. In this study, 10–30% of micro palm oil fuel ash (mPOFA) and 0.5–1.5% of nano-POFA (nPOFA) were incorporated into concrete mixtures to determine the optimum amount for achieving the highest carbonation resistance after 28 days water curing and accelerated CO2 conditions up to 70 days of exposure. The effect of carbonation on concrete specimens with the inclusion of mPOFA and nPOFA was investigated. The carbonation depth was identified by phenolphthalein solution. The highest carbonation resistance of concrete was found after the inclusion of 10% mPOFA and 0.5% nPOFA, while the lowest carbonation resistance was found after the inclusion of 30% mPOFA and 1.5% nPOFA.The carbonation rate of reinforced concrete is influenced by three parameters, namely temperature, relative humidity, and concentration of carbon dioxide (CO These ions induce the corrosion of embedded steel rebars  of river sand obtained in Miri, Sarawak, Malaysia itself did not meet the requirements in accordance with the standards; hence, quarry dust was required to be mixed with sand. The amount of river sand used was 50% and that of quarry dust was 50%. The size of the sand was smaller than 4.5 mm while the size of the quarry dust was between 4.5 mm and 9.5 mm. The fineness modulus of the combined fine aggregates (river sand plus quarry dust) was 2.67.A polycarboxylate ether was used as superplasticizer (SP) in this study. It met the requirements of ASTM C494-16 . The selThe mixture proportions of different concretes were derived based on ACI 211-4R . The cemMixing of the concrete was carried out by a pan mixer. The pouring of the concrete into the mold was done in three layers; compaction was done after every layer filled. The specimens were demolded after 24 h of casting and transferred to water curing at 20 ± 2 °C for 28 days.The XRF  was used to determine the chemical compositions of OPC and POFA. For this, OPC, mPOFA and nPOFA were prepared and stored in the sealed plastic bag with 150 g of each sample.The acquired POFA from Miri, Sarawak, Malaysia was subjected to XRD  analysis to determine its phase composition. Prior to analysis, the samples were prepared in powder form. To collect the XRD spectrum, Cu Kα radiation (λ = 1.54059 Å) generated at 40 kV and 40 mA was used. The 2θ scan range was 20–70°. The step size was 0.015. The database of Joint Committee on Powder Diffraction Standards (JCPDS) was used to ascertain the phase composition of POFA.The determination of morphology of POFA was carried out by SEM  and operated at 15 kV. Prior to perform the SEM experiment, the specimens were mounted into the aluminum stubs. The purpose of mounting was to stabilize the sample for viewing and maneuvering in the SEM chamber. Next, the gold splutter coater was used to coat the mounted specimens. Lastly, the coated specimens were placed inside the SEM instrument. The particle size calculation was carried out by ImageJ software (version Java 1.8.0_172).The slump test was carried out according to ASTM C143 standards  to deter2.The size of concrete specimens used for the accelerated carbonation testing was 280 mm × 70 mm × 70 mm. Accelerated carbonation testing was carried out to determine the carbonation depth in accordance to BS 1881-210:2013 . The con2, 20 ± 5 °C temperature and 55 ± 5% relative humidity in accordance with BS 1881-210:2013 [The accelerated carbonation experiment was performed in 4.0 ± 0.5% CO210:2013 .2 concentration in the atmosphere was estimated to be 0.2% while in urban or industrial areas, the CO2 may rise to 0.4% [2, it is almost 10 times higher compared with natural process. This concluded that using 4.0% CO2 can accelerate the carbonation process.Generally, the CO to 0.4% . Since tThe concrete specimens were placed inside the carbonation chamber for up to 70 days. The carbonation chamber was fabricated by Johndec Centigrade Company in Perth, Australia with acrylic box. The carbonation depth measurement was carried out after 56, 63 and 70 days. The measurement of carbonation depth before 56 days was not recorded, as the carbonation depth was too small to be seen. The overview for the set-up of carbonation chamber is shown in The phenolphthalein solution was used to determine the carbonation depth of concrete. The solution was produced by using 1 g of phenolphthalein powder dissolved in a 100 mL solution of 30 mL deionized water and 70 mL of ethanol solution. After spraying on the concrete specimen, the carbonated area was colorless while the uncarbonated area changed to purple color.2. The sorptivity measurement of the specimens with different time intervals and tolerance is shown in The concrete specimens used for sorptivity experiment were 100 mm diameter × 50 mm height cylinders. Triplicate specimens were used for each of 10 concrete mixtures; therefore, a total of 30 specimens were tested. The sorptivity test was carried out in accordance with the ASTM C1585-13 standards . This te2 while POFA contains SiO2 along with high SiO2 + Al2O3 + Fe2O3. The presence of high content of SiO2 in POFA indicates that it is a pozzolanic material. The chemical compositions of OPC and POFA are presented in 2 liberated from cement hydration in concrete to form secondary C-S-H.The XRD of mPOFA and nPOFA are presented in L) of different mineral phases was calculated by the Scherrer equation as shown below.The crystallite size  can be seen inside the concrete pores and matrix (3S) and dicalcium silicate (C2S) [2 inside M0 (There is obvious densification of concrete when incorporating mPOFA and nPOFA as shown in d matrix a when note (C2S) , which cnside M0 a mixture2. The floc and fibrous C-S-H phases filled the pores of the concrete when a greater amount of POFA was incorporated, as obvious from 2/g) compared with mPOFA; hence, the hypothesis given in this study correlates with their work and suggests that increased surface area induces the precipitation of hydration products [POFA has been used with OPC in M10N1, M10N3, M30N1, and M30N3 concrete mixtures whose SEM images are shown in products .In concrete mixtures, both mPOFA and nPOFA acted as nucleation sites and accelerated the precipitation of hydration products such as C-S-H gel in the cementitious matrix . OPC hasThe sizes of different crystals present in various concrete mixtures were calculated from Concrete specimens were removed from the carbonation chamber and placed onto the wet cutting machine. The concrete specimens were sliced 50 mm thick after each exposure period. Phenolphthalein solution was then sprayed onto the sliced surface to identify the carbonated and uncarbonated areas. The Vernier caliper was used to measure the depth of the carbonated area.2 into the concrete, thus, higher carbonation resistance can be found. However, not all mixtures have positive influence on carbonation resistance. M10N1 has the most positive effect on carbonation resistance among all concrete mixtures. Moreover, the carbonation effect tends to increase with exposure periods [The incorporation of POFA into the concretes can influence the carbonation properties. Higher compactness and densification of concrete will lead to difficulty in penetration of CO periods . TherefoThe presence of POFA significantly influenced the carbonation resistance of concrete. In general, the lowest and highest resistance to carbonation was observed for M30N3 (contained 30% mPOFA with 1.5% nPOFA) and M10N1 (contained 10% mPOFA with 0.5% nPOFA), respectively . M10N1 h2 into concrete than micro-sized POFA. Nano-sized POFA has a better micro-filling ability to reduce porosity causing difficulties to penetrate CO2 into concrete. Therefore, using nPOFA provided higher carbonation resistance than mPOFA.The negative impact of a relatively high amount of mPOFA on the carbonation resistance of concrete can be compensated by using nPOFA. The comparison of M10N1 with M30N1 and M10N3 shows that a higher amount of mPOFA produces lower carbonation resistance compared with higher nPOFA. When the amount of mPOFA was increased from 10% to 30%, the carbonation depth extended from 1 mm to 11 mm while increasing nPOFA from 0.5% to 1.5% increased the carbonation depth from 1 mm to only 3 mm. These results suggested that nano-sized POFA has a better ability to resist the penetration of COIn summary, the higher amount of POFA incorporated in concrete increases the number of pores with greater porosity, resulting in a higher carbonation depth (lower carbonation resistance). This is because POFA had a slower pozzolanic reaction  and the The results of sorptivity test with error bars for different 28 days old concrete mixtures with various proportions of OPC and POFA are shown in The water sorptivity values increased with time for all concretes due to the suction mechanism of capillary water molecules. The incorporation of a certain amount of POFA (10%) into concrete showed a greater decrease in sorptivity, which means that it provided a higher resistance to moisture absorption by capillary suction. This indicates that more binding product (C-S-H) formed to refine the pore structure in the concrete matrix, thus producing a denser microstructure in the concrete.The lowest levels of water sorptivity were observed for M10N1 and M10N2, both of which contained 10% mPOFA but 0.5% and 1% nPOFA, respectively. The time for suction of the water molecules through the pores of concrete was lower for M10N1 compared with other concrete mixtures, thus less water sorptivity was observed. Interestingly, although M10N2 had relatively high carbonation depth, it provided significantly low water sorption value, as compared to other concretes except M10N1. This perhaps occurred because the water sorptivity depends not only on the microstructure and compactness of concrete but also on the different processes of experiment. The sorptivity experiment was performed after 28 days of water curing and then 1 min–60 min alternation in wetting time. There is a possibility that after curing in water, when the sorptivity experiment was performed, the water absorption was less due to the reduced degree of dryness in concrete. In contrast, the carbonation measurement was carried out for up to 70 days where the likelihood for dryness was greater, which caused the formation of greater large-size pores in the concrete. Therefore, it showed less carbonation resistance.(a)2 as well as SiO2 + Al2O3 + Fe2O3 compared with OPC.XRF results show that POFA has higher SiO(b)The LOI value of treated POFA is greatly reduced compared with raw POFA. After the treatment of raw POFA, the LOI value is reduced by 28.75% and 33.33% for mPOFA and nPOFA, respectively.(c)XRD results reveal that mPOFA and nPOFA contain two major phases, namely Quartz and Cristobalite, along with amorphous silica, which participated in pozzolanic reaction.(d)SEM results show that mPOFA had crushed or irregular-shaped particles and found to be bigger in size compared with nPOFA.(e)Inclusion of nPOFA can reduce the size of pores in the concrete matrix due to its better micro-filling ability than mPOFA.(f)The concrete mixture with 10% mPOFA and 0.5% nPOFA, designated as M10N1, can have higher carbonation resistance and lesser sorptivity compared with OPC and other mixtures. However, a higher amount of micro- and nano-POFA has detrimental and negative effects on carbonation resistance and water sorptivity results.Based on the experimental results obtained in the present study and associated discussion, the following conclusions can be drawn:


To act upon the world, creatures must change continuous variables such as muscle length or chemical concentration. In contrast, decision making is an inherently discrete process, involving the selection among alternative courses of action. In this article, we consider the interface between the discrete and continuous processes that translate our decisions into movement in a Newtonian world—and how movement informs our decisions. We do so by appealing to active inference, with a special focus on the oculomotor system. Within this exemplar system, we argue that the superior colliculus is well placed to act as a discrete-continuous interface. Interestingly, when the neuronal computations within the superior colliculus are formulated in terms of active inference, we find that many aspects of its neuroanatomy emerge from the computations it must perform in this role. To induce changes in the external world, it is necessary to contract muscles or secrete chemicals. Such processes necessarily involve the manipulation of continuous variables—muscle length or chemical concentration. In addition, animals must make decisions. To do so, they must entertain several different possible courses of action, or policies. Ultimately, they must select one of these actions or policies that are necessarily discrete. We draw on recent work that considers the interactions between the neuronal processing of discrete and continuous quantities , with theta and alpha cycles as the most popular hypothesized units of perceptual time q decision processes are a natural form for the generative model because they are defined on discrete state spaces  to pursue. To do so, we define prior beliefs about the probability of each policy. Active inference mandates the selection of policies that minimize free energy. However, free energy is a function of outcomes, which are not known for future time steps. The solution to this is to select policies that minimize the expected free energy. To convert the expected free energy for each policy to a probability distribution (that sums to one), we use a softmax  function, 2.3 At the level of biological effectors (glands and muscles) and sensory receptors, the variables the nervous system must deal with are continuous. In other words, to enact a selected policy, it is necessary to map categorical representations to the physical world with continuous states and time. Muscles generate continuous forces, while photoreceptors signal light intensity. This means that there must be a generative model that maps the abstract, discrete outcomes from the generative (MDP) model above, to continuous data  prior beliefs in the latter. The final thing to specify is the process by which the continuous state-space model informs the discrete model. In other words, what sort of evidence is passed from the continuous to the discrete part of the (active) inference scheme? In brief, the discrete part of the generative model provides prior constraints on the continuous part, while the continuous part reciprocates with Bayesian model evidence for the discrete hypotheses entertained by the discrete part to enable Bayesian belief updating. This updating entails the selection of alternative hypotheses (outcomes) that constitute empirical priors at the continuous level.To adjudicate between these hypotheses, we need to compute the posterior probabilities over each outcome . We give an abbreviated outline of this (Bayesian model reduction) procedure here  that can be passed through a softmax function to give the posterior over each outcome model, To convert the evidence for each model back to discrete time, we integrate the model evidence (free energy) over the time period corresponding to one theta cycle. This is then combined with the prior over the model to give a vector  simulations is to illustrate the interactions between the discrete and continuous domains of the oculomotor system. As such, we chose a simple behavioral paradigm with three possible fixation locations . We then set the prior preferences . A Bayesian model average over outcomes then results in the selection of superior collicular buildup neurons that represent the error between the current belief about eye position (given by the fixation neurons) and the anticipated rightward location. These then induce changes in the fixation neuron activity. During the next 100 ms, as the eyes move to fulfill this belief, we can see the resolution of the prediction error in the superior colliculus buildup layer through the movement of the hill of activity toward the pole.5 5.1 Variational message passing is not the only local message passing scheme that has been associated with neuronal signaling. Belief propagation Pearl,  is one aA further possibility is that the messages we have described might be computed through sampling, or Monte Carlo, approaches  speech, locomotion, and autonomic regulation. Language is made up of discrete units  that are expressed as continuous changes in auditory frequencies generated by contraction of the laryngeal  muscles  to other systems. While the ideas we have presented are generally applicable, it will be necessary to specify the generative models required to solve locomotive, autonomic, and abstract decision-making problems. Finally, although the computational anatomy we have proposed has a high degree of face validity, it will be necessary to establish its predictive validity.One way to do so would be to use computational fMRI  via a graphical user interface by typing in Although the generative model changes from application to application, the belief updates described in this article are generic and can be implemented using standard routines (here spm_MDP_VB_X.m). These routines are available as Matlab code in the SPM academic software:


In this study, the shrinkage and creep of concrete containing graphene oxide (GO) nanosheets were experimentally and theoretically investigated. Experiments for the shrinkage and creep of concrete with 0.02% and 0.08% GO nanosheets by the weight of cement and common concrete were carried out. Subsequently, the influence of GO nanosheets on the shrinkage and creep of concrete was analyzed and discussed. A modified model was developed to accurately predict the shrinkage and creep of concrete containing GO nanosheets after models for predicting shrinkage and creep of common concrete were compared and the influential factors and application scope were determined. Results indicate that: (1) GO nanosheets can increase the shrinkage strain and reduce the creep coefficient of concrete, and (2) a modified ACI209 (92) model can accurately predict the shrinkage and creep of concrete containing GO nanosheets. Factors considering concrete strength can be introduced in the model to improve the model accuracy. Concrete has been extensively applied to the building field, owing to its advantages such as easy material obtaining and strong plasticity, since it was invented ,2,3. HowIn addition, the 2D nanometer material graphene oxide (GO) nanosheet is one of the added materials that has received much attention . As the At present, there are many studies about the influence of GO nanosheets on the mechanical property and microstructure of cement and concrete . Recent There are few studies about the influence of GO nanosheets on the shrinkage and creep performance of cement and concrete, and such research is still at an early stage. Xu et al.  believedAlthough there are many studies about the mechanical property ,17,19,20In order to investigate the shrinkage and creep effect of concrete containing GO nanosheets and to establish a shrinkage and creep model, the authors carried out experiments with concrete containing GO nanosheets.The shrinkage and creep experiments of concrete containing GO nanosheets were performed in the Civil Engineering Material Lab of Chongqing University. The cement used for testing was ordinary Portland cement P.O 42.5, and the chemical components and percentage of the cement are shown in The preparation method and sample size are determined according to the standard test methods of long-term performance and durability of ordinary concrete (GB/T 50082-2009). C50 concrete was prepared for the shrinkage and creep experiment, and the sample size was 100 mm × 100 mm × 400 mm. The water-cement ratio (w/c) was 0.35. According to previous studies ,20,22, tThe material selection and their combinations were designed according to the standard test method of the mechanical properties of ordinary concrete (GB/T 50081-2002). In order to enable the graphene oxide powder to be dissolved and dispersed well in water, 0.02% and 0.08% GO-water solution was made first, and then the polycarboxylate superplasticizer was added to the graphene oxide aqueous solution. After that, the solution was added to concrete. The GO-water is tested using microscopic equipment used in a previous study . FinallyA deformation meter, as shown in The samples were maintained in the standard curing room for 7 days, and the axial compressive strength test was conducted for various components before the shrinkage and creep test, as shown in After the axial compressive strength test was completed, the micrometer gauge was installed on the sides of the shrinkage and creep samples, as shown in Concrete shrinkage includes plastic shrinkage, autogenous shrinkage, drying shrinkage, and carbonated shrinkage. The shrinkage strain of the test samples was measured after 7 days of maintenance, so plastic shrinkage produced in the concrete molding and hardening process was not considered. Carbonated shrinkage often takes a long time, so it was also ignored. The entire shrinkage process in the experiment included autogenous shrinkage and drying shrinkage. Autogenous shrinkage is the macro volume shrinkage triggered by self-desiccation in the concrete when the concrete has no moisture exchange with the outside environment. Drying shrinkage refers to shrinkage caused by water loss in the environment.stε is the shrinkage rate when the test period of concrete sample is t(d), and t is calculated from the initial start of the test; bL is the scale distance of concrete sample (400 mm in this experiment); 0L is the initial reading of sample length (mm); tL is the length reading of concrete sample when the test period is t(d) (mm).The shrinkage value gained in the experiment was processed according to the following equation, and the concrete shrinkage was gained:The change of the shrinkage strain of concrete with time was obtained from the test, as shown in 2, which will produce a chemical reaction with GO(–COOH) in graphene. Hence, the hydration process is accelerated [The shrinkage strain of concrete with GO nanosheets was higher than the shrinkage strain of concrete without GO nanosheets after the 3rd day. This is possibly because when GO nanosheets were mixed with cement in the beginning, the electronegative oxygen functional groups in GO nanosheets and the metal cations in the cement compound adsorbed each other rapidly, and the formation of flocculent structure reduced the mobility of the cement . Such nuelerated ,37, the On the 60th day, the shrinkage strain of the three groups reached the peak value at the same time, and the values increased with the increase of the addition of the amount of GO nanosheets. After the 60th day, the shrinkage strain began to slowly decline. In the later hydration process, the increase rate of shrinkage strain dropped gradually. This is because: (1) the moisture adsorbed by GO nanosheets is released, which will help to solidify the concrete  and to wctε is the creep strain (mm/m) when the concrete samples are loaded for t days, and it is accurate to 0.001 mm/m; tL is the total deformation value (mm) when the concrete samples are loaded for t days, and it is accurate to 0.001 mm; L0 is the initial deformation value (mm) in loading, and it is accurate to 0.001 mm; bL is the scale distance (mm), and it is accurate to 1 mm; tε is the shrinkage value (mm/m) of the shrinkage samples under the same age, and it is accurate to 0.001 mm/m.Equation (2) was used to calculate the creep strain of concrete.tφ is the creep coefficient after loading for t days, and it is accurate to 0.001 mm/m; ε0 is the initial strain value (mm/m) in loading, and it is accurate to 0.001 mm/m.The creep coefficient was used to measure the creep behavior of concrete with GO nanosheets, and is expressed by:In According to the comparison of the creep coefficient curve of different concrete samples, the creep coefficient of the GOSC-1 and GOSC-2 groups are obviously lower than that of the PSC group, indicating that the addition of GO nanosheets can significantly reduce the creep coefficient of concrete. Moreover, the creep coefficient of samples with a larger dosage is smaller than the creep coefficient of samples with a smaller dosage, as GO nanosheets can enhance the compressive strength of concrete. Furthermore, within a certain scope, the higher the GO nanosheets content is, the bigger the compressive strength will be ,40 and tA previous study  can alsoTraditional models for predicting shrinkage and creep of common concrete are presented in As can be seen from As mentioned previously, traditional models were established based on test data that were obtained in certain test conditions. Accordingly, these models have their own application scope. Details of the application scope are summarized in The test conditions documented in In α and β). Accordingly, models for predicting shrinkage and creep of concrete containing GO nanosheets are modified by:sh∞ε and ∞φ are the final values of shrinkage strain and creep coefficient in the ACI209 model.The 1st Opt fitting software was used to fit the concrete containing 0.02% and 0.08% GO nanosheets by weight of cement to get the coefficients in Equations (5) and (6). The influential and exponential coefficients obtained from the weighting are presented in Using the modified model, the shrinkage and creep of the concrete containing 0.02% and 0.08% GO nanosheets by weight of cement are calculated and compared with that predicted by the ACI 209 (92) model and the experimental result, as shown in In cmf is the average cube crushing strength of concrete in 28 days.For the purpose of convenient use, the coefficients in Equations (5) and (6) are modeled. Because of the different fundamental characteristics of concrete, such as cement variety, water cement ratio, mineral admixtures, and aggregates, the concrete shrinkage and creep are different. Meanwhile, the differences of test conditions will also lead to the differences of concrete shrinkage and creep. Therefore, the coefficients of concrete strength influence the final values of shrinkage and creep as well as the relation between the concrete strength at 28 days and shrinkage and creep development curve indexes. Linear square fitting was conducted according to the values in The above modeled coefficients were introduced into Equations (5) and (6) to obtain Equations (9) and (10), which can be used for modeling the shrinkage and creep of concrete containing GO nanosheets.This study has compared the shrinkage and creep of concrete containing 0.02% and 0.08% GO nanosheets by weight of cement and common concrete. The shrinkage and creep on the 1st, 3rd, 7th, 14th, 28th, 45th, 60th, 120th, and 150th days during the loading age were experimentally obtained. This study has provided experimental evidence for other related investigation. Furthermore, the existing models for the shrinkage and creep of common concrete have been modified to predict the shrinkage and creep of concrete containing GO nanosheets, which will provide more reference for other researchers. The main conclusions are drawn as follows.(1) GO nanosheets can increase the shrinkage strain and reduce the creep coefficient of concrete. The higher the dosage is, the larger the influence will be.(2) The influence of GO nanosheets on the shrinkage strain of concrete increases first and then drops as the loading age rises. In a certain scope, with the increase of the dosage, it often takes a longer time to get a peak value.(3) The influence of GO nanosheets on the creep of concrete does not present a unified changing trend in the loading age. However, in a certain scope, the higher the dosage of GO nanosheets is, the larger the influence on the creep coefficient will be.(4) A modified ACI209 (92) model can accurately predict the shrinkage and creep of concrete containing GO nanosheets. Factors considering concrete strength can be introduced in the model to improve the model accuracy.


This paper evaluates the impact of different types of fibers on the engineering features of CSA-based concretes at different water-cement ratios of 0.35 and 0.28. In this study, metallic fibers including double hooked-end steel fibers and hooked-end steel fibers, and non-metallic fibers  fibers) were utilized at fiber content of 1%. The mechanical properties of concretes were assessed at different curing ages. Dimensional stability of the concrete mixes was also examined. The morphology of the fractured specimens was studied by using the SEM method. The results indicate that the engineering properties of concrete were improved by introducing fibers to the concrete, irrespective of fiber type. The results show that DHE steel fiber has an important effect on the flexural performance of CSA cement-based concretes and results in deflection-hardening behavior. It was observed that fibers and particularly PVA fibers cause a decrease in shrinkage deformation. Microstructure tests demonstrate that prismatic ettringite is the main hydration product of CSA cement-based concrete. The SEM observation also confirms that the inclusion of CSA cement in concrete improves the cohesiveness between the fibers and cement matrix.Calcium sulfoaluminate (CSA) cement has recently gained increased attention due to its lower amount of CO Convemissions . Using amissions . CSA cemmissions . Thereafmissions ,8. CSA cmissions ,10,11.4A3$), and depending on the raw material composition, it may contain minor phases like belite (C2S), calcium sulfate (C$), and aluminoferrite (C4AF) [4) content between 18–20%, 22–24%, and higher than 25% resulted in slight shrinkage during setting, minimal dimensional change, and notable expansion, respectively [The main constituent of CSA clinker is ye’elimite (Ce (C4AF) ,13,14. Te (C4AF) , while ie (C4AF) . Hence, e (C4AF) . The preCement-based materials are weak materials in term of tensile strength, and thus concrete has a brittle behavior and cracks are practically unavoidable ,19. CracDespite the advantages of concrete compared to other construction materials, its brittleness can shorten the service life of structures. Moreover, drying shrinkage is critical for large surface area concrete structures and can decrease the overall strength and durability of concrete due to the formation of cracks. The objective of this study is to explore the impact of different fibers on the engineering properties of concretes manufactured with CSA cement. The properties of CSA cement-based concretes and particularly their hydration products have been assessed by other researchers ,32,33. ACalcium sulfoaluminate cement (CSA) produced by Italcementi Group ,) was utilized in this study. The chemical composition and physical properties of CSA cement are listed in Silica fine aggregate and coarse aggregate were employed at 50.3% and 49.7%, respectively, to assure a uniform concrete. The features of the aggregates are presented in A Driver Care 10-Sika as a superplasticizer agent and tartaric acid as a retarder were utilized to adjust the workability and setting time of the concrete mixes. Double hooked-end (DHE) steel fibers with aspect ratio of 65, hooked-end (HE) steel fiber with aspect ratio of 65, and polyvinyl alcohol fiber (PVA) with aspect ratio of 75 were employed in this study. The appearance of different fibers is shown in The absolute volume method  was usedCompressive strength tests were conducted on the cubic specimens with 100 mm dimension as per ASTM C39  by usingThe results of compressive strength tests for concrete developed at water-cement ratios of 0.35 and 0.28 are shown in The results further demonstrate that strength development in concretes produced at a higher water-cement ratio  was higher compared to that of concretes manufactured at a water-cement ratio of 0.28. For instance, the average 28 and 56-day compressive strengths of FRC with water-cement ratio of 0.35 were 19% and 25% higher than their 7-day strength, while the increase was 12% and 16% in FRC produced at a water-cement ratio of 0.28. This can be explained by the fact that the free water that was available in concretes with a water-cement ratio of 0.28 was consumed very fast by ye’elimite to generate ettringite, and a lesser amount of water was available for its further hydration and strength gain. On the other hand, in concretes that were manufactured at a water-cement ratio of 0.35, further reactions occurred at later ages, which consequently developed higher strength growth.The failure mode of high performance concrete under compression loads is shown in The splitting tensile strength results of different FRC mixes at water-cement ratios of 0.35 and 0.28 are shown in For FRC developed at a water-cement ratio of 0.28, a similar trend to concretes with a water-cement ratio of 0.35 was observed. The addition of fibers in concrete caused an improvement in splitting tensile strength, irrespective of the type of fibers. As can be seen in The results further demonstrate that the curing of specimens had a higher impact on the improvement of FRC strength when compared to that of the plain CSA concrete. For example, the average 28- and 56-day splitting tensile strengths of FRC with water-cement ratio of 0.35 were 42% and 57% higher than their 7-day strength. This suggests that the chemical cohesion between fibers and cement matrix was increased over time because of cement expansion, and consequently caused an increment in the splitting tensile strength of the concrete. The impact of curing age on the enhancement of splitting tensile strength of concrete was reduced by decreasing the water-cement ratio. For example, the average 28- and 56-day splitting tensile strengths of FRC with a water-cement ratio of 0.28 were 30% and 42% higher than their splitting tensile strength at seven days. The reason is that in concretes with low water-cement ratio , free water was consumed significantly in the early periods and developed higher strength at seven days. Therefore, there is a lack of free water inside the concrete for further cement hydration at later periods .The 28-day modulus of elasticity of different FRC mixes with water-cement ratios of 0.35 and 0.28 is shown in The Load-CMOD curves for different fiber-reinforced concretes at curing ages of 7, 28, and 56 days are illustrated in In general, a trend similar to the flexural behavior of concretes was developed at a water-cement ratio of 0.35 for concrete mixes with a water-cement ratio of 0.28. The addition of fibers increased the flexural strength of concrete, irrespective of fiber type. For example, the improvement in flexural strength of CSA-DHE1, CSA-HE1, and CSA-PVA1 mixes ranged from 86% to 92%, 47% to 56%, and 10% to 20%, respectively, depending on the testing age. Similarly, a deflection-hardening behavior was achieved in the CSA-DHE1 mix, while the addition of other kinds of fibers led to a deflection-softening behavior. The results indicate that the highest flexural strength was achieved by the CSA-DHE1 mix—its flexural strength at 56 days was 16.9 MPa.1, Fr2, Fr3, and Fr4 show residual flexural strengths matching CMOD at 0.5 mm, 1.5 mm, 2.5 mm, and 3.5 mm, respectively. Generally, it can be seen that an increment in CMOD results in a decrease in residual flexural tensile strengths. However, the flexural performance of CSA-DHE1 is different from other mixes and a deflection-hardening behavior was observed. The results indicate that Fr2 is the highest residual flexural tensile strength in the mix containing 1% DHE steel fibers, and a reduction took place in Fr3 and Fr4. For instance, the Fr2 and Fr3 of the CSA-DHE1 mix cured for 28 days increased by 12% and 5% as compared to its Fr1, while the Fr4 reduced by 18% as compared to its Fr1. The results of the CSA-HE1 mix at 28 days indicate that the Fr2, Fr3, and Fr4 reduced by 15%, 33%, and 49%, respectively as compared to its Fr1. These results approve the important effect of DHE steel fibers in enhancing the flexural behavior of concrete and can undoubtedly have a key helpful contribution in designing concrete structure subjected to bending load.The residual flexural tensile strengths for different FRC at curing ages of 7, 28, and 56 days are illustrated in 3 of CSA-DHE1, CSA-HE1, and CSA-PVA1 mixes at 28 days were 15.4, 6.4, and 1.2 MPa, respectively. As can be noticed in 3 and Fr4 were slightly lower than Fr2. This can be explained by the fact that the DHE steel fibers bridge the macro-cracks and absorb more energy as the flexural load exceeding the strength of concrete and its anchoring mechanism have an important influence on the improvement of flexural strength [Similarly, the results of concrete prepared at a water-cement ratio of 0.28 indicate that the residual flexural tensile strengths of concrete containing 1% DHE steel fibers were significantly higher with respect to those of the concretes reinforced with 1% HE steel or PVA fibers, particularly at greater CMOD. For instance, the Frstrength .Crack propagation on the surface of concrete beams containing different types of fibers is illustrated in It should be noted that the orientation of fibers and their distribution in the concrete beams have an important effect on the flexural performance of concrete. The cross sections of fracture concrete beams containing different types of fibers and the distribution of fibers on their surface are shown in The results of the dimensional stability test under drying conditions for different fiber-reinforced concretes at water-cement ratios of 0.35 and 0.28 are shown in The results further indicate that contrary to concretes manufactured at a higher water-cement ratio , no evidence of expansion occurred in CSA-based mixes at a water-cement ratio of 0.28. In other words, the expansion of concrete at day 1 has been fully canceled and a greater amount of shrinkage took place in the early periods as compared to concretes with a water-cement ratio of 0.35. This can be explained by the appearance of autogenous shrinkage that occurred in these concretes as a result of higher cement content and lower water-cement ratio. However, the shrinkage strain of concretes at later periods  was lower as compared to concrete with a higher water-cement ratio. Cheung and Leung  studied SEM observation was performed in the secondary electron (SE) mode to study the microstructure of concrete; the images are shown in The results indicate that the addition of fibers causes an increase in the compressive strength of concrete, irrespective of fiber type. The compressive strength improvement of FRC at a water-cement ratio of 0.35 varied from 1% to 13%, while this improvement at a water-cement ratio of 0.28 ranged from 2% to 20%, depending on fiber type and testing age.The inclusion of 1% fibers and particularly DHE steel fibers in CSA cement-based mixes results in an increase in the splitting tensile and flexural strength of FRC. Introducing DHE steel fibers in CSA concrete results in a deflection-hardening behavior in concrete, while concretes reinforced either with HE steel fibers or PVA fibers exhibit a deflection-softening response. The improved post-cracking behavior of the FRC can be explained by the fact that the DHE steel fibers inhibit the development of macro-cracks through the anchoring mechanism.The addition of fibers in concrete has no important influence on the elastic modulus of FRC.Introducing discrete fibers in CSA cement-based concretes reduces the shrinkage deformation of FRC, irrespective of the water-cement ratio and fiber type. CSA-PVA1 shows the lowest shrinkage among different mixes and its final shrinkage was decreased by 25% and 27% at water-cement ratios of 0.35 and 0.28, respectively.The prismatic ettringite crystals with 0.29–0.7 µm wide, and 2–6 µm length are the primary hydration products of CSA mix with a water-cement ratio of 0.35. The results further indicate that the size of ettringite crystals is reduced by decreasing the water-cement ratio, and crystals with 0.1–0.5 µm wide, and 2–6 µm length were developed. The SEM results also confirms that the chemical cohesion between the cement matrix and fibers has been improved.This paper evaluated the effect of different types of fibers on the engineering properties of CSA cement-based concretes. The following conclusions are presented from the experimental results:


Pelosinus lilae” strain UFO1, was isolated under strictly anaerobic conditions from an Fe(III)-reducing enrichment established with uncontaminated soil from the Department of Energy Oak Ridge Field Research Center, Tennessee. “P. lilae” UFO1 is a rod-shaped, spore-forming, and Gram-variable anaerobe with a fermentative metabolism. It is capable of reducing the humic acid analog anthraquinone-2,6-disulfonate (AQDS) using a variety of fermentable substrates and H2. Reduction of Fe(III)-nitrilotriacetic acid occurred in the presence of lactate as carbon and electron donor. Ferrihydrite was not reduced in the absence of AQDS. Nearly complete reduction of 1, 3, and 5 ppm Cr(VI) occurred within 24 h in suspensions containing 108 cells mL−1 when provided with 10 mM lactate; when 1 mM AQDS was added, 3 and 5 ppm Cr(VI) were reduced to 0.1 ppm within 2 h. Strain UFO1 is a novel species within the bacterial genus Pelosinus, having 98.16% 16S rRNA gene sequence similarity with the most closely related described species, Pelosinus fermentans R7T. The G+C content of the genomic DNA was 38 mol%, and DNA-DNA hybridization of “P. lilae” UFO1 against P. fermentans R7T indicated an average 16.8% DNA-DNA similarity. The unique phylogenetic, physiologic, and metal-transforming characteristics of “P. lilae” UFO1 reveal it is a novel isolate of the described genus Pelosinus.The capability of microorganisms to alter metal speciation offers potential for the development of new strategies for immobilization of toxic metals in the environment. A metal-reducing microbe, “ In addilla spp. , 1996. Tlla spp. . Althouglla spp. , this grormation , and exhormation , potentiIn situ biological treatment can be less expensive and less disruptive than traditional ex situ technologies for remediation of metal-contaminated sites, as it relies on indigenous microorganisms to achieve clean-up of hazardous wastes , Tennessee. The unique phylogenetic and metal-transforming characteristics of “P. lilae” UFO1 reveal it is a novel species of the described genus designated Pelosinus.s wastes . Examina2 and processed in an anaerobic glove bag under N2-CO2-H2 (75:20:5).Strict anaerobic techniques were used throughout this study . Sedimen3)3⋅9H2O in 0.5 L water and adjusting to pH 7.0 with ∼345 mL 1 M KOH, and the resulting precipitate was washed thoroughly in DI water (Enrichment cultures were initiated in 27 mL anaerobic pressure tubes (Bellco Glass) containing 9 mL anaerobic freshwater medium (ATCC medium 2129) and ∼1 g FRC sediment. A suspension of 2-line ferrihydrite (∼1 M) was synthesized by dissolving 40 g Fe or as follows (per liter): 0.5 g yeast extract; 0.5 g proteose peptone; 0.5 g casamino acids; 0.5 g glucose; 0.5 g soluble starch; 0.3 g sodium pyruvate; 0.3 g K2HPO4; 0.05 g MgSO4 .After isolation, “ g MgSO4 , supplem2:CO2 (80:20). Tubes or vials were sealed with thick butyl-rubber stoppers and sterilized by autoclaving. FW medium was used for experiments examining electron donor and acceptor utilization.Anaerobic, bicarbonate-buffered, freshwater (FW) medium was prepared, as described previously by Cells were harvested by centrifugation from cultures grown in R2A broth, washed twice in anoxic FW medium, and suspended in sterile, pH 7, anoxic FW medium. For screening of potential electron donors and acceptors, sterile anoxic stock solutions were prepared for a variety of electron donors and acceptors and added to the FW medium. Utilization was evaluated in triplicate incubations.P. lilae” UFO1 to reduce the following electron acceptors was examined: Fe(III)-NTA, 2 line-ferrihydrite, AQDS, Cr(VI), As(V), NO3-, NO2-, SO42-, and SeO42-. The ability of washed cell suspensions to reduce Cr(VI) was examined under non-growth conditions, defined here by the omission of phosphate from the FW medium. Washed cells were added to the medium to give a concentration of 108 cells mL-1.The ability of “® AN MicroPlate™  (Carbon substrate utilization by strain UFO1 was examined under anaerobic conditions using the BIOLOG States) . AnaerobPotentially fermentable substrates were examined in FW medium (containing 0.5 mM cysteine as a reducing agent) in the absence of an electron acceptor. The following substrates (10 mM each) were tested: fructose, fumarate, glucose, glycerol, lactate, malate, mannitol, pyruvate, succinate, and 0.3% wt/vol. yeast extract. Fermentation of substrates was defined as the ability to grow after three successive 10% transfers, and growth was monitored by measuring optical density at 600 nm.2DS) were measured spectrophotometrically at 405 and 325 nm under anoxic conditions. The molar absorptivity coefficients calculated for AQDS were 𝜀405 = 0.13 and 𝜀325 = 6.1 mM-1 cm-1; for AH2DS, the coefficients used were 𝜀405 = 10.3 and 𝜀325 = 0.8 mM-1 cm-1. Aqueous Fe(II) in sample filtrate (filtered through 0.2-μm filter) that was diluted 1:10 in 0.5 N HCl was quantified spectrophotometrically at 562 nm with ferrozine  was evaluated by measuring soluble As(V) at 865 nm in samples preserved in KIO3 and HCl as described previously . The spectrometer was calibrated employing the Au 4f7/2, Cu 2p3/2, and Ag 3d5/2 photopeaks with binding energies of 83.99, 932.66, and 368.27 eV, respectively. A consistent 400-μm spot size was analyzed on all surfaces using a monochromatized Al Kα (hν = 1486.6 eV) X-ray source at 300 W and a pass energy of 46.95 eV for survey scans, and 11.75 eV for high-resolution scans. The system was operated at a base pressure of 10-8 to 10-9 torr. An emission angle (2ϕ) of 45° was used throughout. Following baseline subtraction (2–CH2–)n] to a binding energy (Eb) of 284.8 eV (X-ray photoelectron spectroscopy (XPS) was employed to determine the valence state of Fe in cell suspensions incubated with 5 mM AQDS and 2 line-ferrihydrite or ferrihydrite alone. The extent of Fe(III)-reduction at both uncolonized and colonized Fe(III)-oxide surfaces was examined. Ferrihydrite samples were dried onto a Si wafer before mounting for XPS analysis. Samples were mounted for XPS in an anaerobic glove box and transported to the spectrometer in a plate chamber sealed under an anaerobic atmosphere. Brief (<5 s) exposure to air occurred during introduction of the samples into a Ntraction , curve-f284.8 eV .p level models describing multiplet splitting associated with ferrous and ferric ions have been demonstrated by Gupta and Sen . The G+C content of genomic DNA was determined by high-performance liquid chromatography using the method of P. lilae” UFO1 were grown in anoxic R2A broth at 30°C overnight and harvested by centrifugation. The pellet was suspended in a mixture of isopropanol and water (1:1) and submitted to DSMZ for DNA-DNA hybridization with Pelosinus fermentans R7T (DSM 17108). DNA was isolated from the cell pellet using a French pressure cell and purified by chromatography on hydroxyapatite as described by in situ temperature probe (Varian). Percent DNA-DNA similarity was measured in 2X saline sodium citrate (SSC) solution at 65°C.Cells of “P. lilae” UFO1 was grown on R2A broth containing 20 mM fumarate at 30°C. The cells were harvested by centrifugation, frozen (-20°C), and analyzed by Microbial ID  for fatty acid methyl ester content.An overnight culture of “2O) using a combination of Peltier cooling and differential pumping. ESEM imaging looked first at the edges of the mount then progressed inward to find regions of optimal cell density, minimal desiccation, and minimal precipitation of salts.Cells were grown overnight at 30°C in R2A broth containing 20 mM fumarate for morphological characterization using a Philips XL 30 Environmental Scanning Electron Microscope (ESEM), operating at 10 kV with a typical target current of 1.75 μA. Prior to imaging, the cells were washed twice and re-suspended in phosphate buffered saline (pH 7). Droplets of the washed cell suspension were placed in a conical ESEM mount to maximize solution volume. The chamber was maintained at ∼45% relative humidity . PCR amplification of the 16S rRNA gene was performed with primers 8F (5′-AGAGTTTGATCCTGGCTCAG-3′) , 250 μM dNTPs, 800 nM of each primer, 2 mM MgSO4, and 1.5 μL of genomic DNA template. The PCR amplification conditions were as follows: an initial 95°C denaturation for 5 min, followed by 30 cycles of 95°C denaturation for 1 min, 56.1°C primer annealing for 1 min, and 72°C extension for 2.5 min, and then a final extension at 72°C for 4 min. PCR products were purified using the Qiagen QIAquick PCR Purification Kit  per manufacturer’s instructions. The 16S rRNA gene PCR products were sequenced at the Idaho State University Molecular Research Core Facility (MRCF) on an ABI 3100 automated capillary sequencer  using 8F, 519R (5′-ATTACCGCGGCTGCTGG-3′)  according to the manufacturer’s instructions. Plasmids were purified from clones using the Qiagen Qiaprep® Spin Miniprep kit  and sequenced directly using primers M13F (5′-GTAAAACGACGGCAG-3′), M13R (5′-CAGGAAACAGCTATGAC-3′), T3 (5′-ATTAACCCTCACTAAAGGGA-3′), and T7 (5′-TAATACGACTCACTATAGGG-3′) at the ISU MRCF. The GenBank accession number for the 16S rRNA sequence of “P. lilae” UFO1 is DQ295866, and the draft genome accession number is CP008852.Genomic DNA was extracted from “TCAG-3′) , 907R (5TCAG-3′) , 704F (5TCAG-3′) , and 149TCAG-3′) . Each 50CTGG-3′) , 907R, 7CTGG-3′) , and 1491 . Phylogenetic tree was inferred within the ARB software by the Maximum Likelihood method PHYML, version 20130708 (Species representing the Negativicutes Class were determined based on the List of Prokaryotic Names with Standing in Nomenclature (LPSN)1 . Phyloge1  software1 , motile, and stains Gram-variable. Structures that appeared to be spores were also visible . Extracellular polymeric substance (EPS) is associated with individual cells, as judged by electron-dense materials surrounding the cell periphery. The production of spores was supported by the observation that a 10% inoculum from thermally-treated (85°C for 32 min) cell suspensions of “P. lilae” UFO1 could be re-grown in R2A broth and also exhibited the ability to reduce AQDS in the presence of H2 upon transfer to fresh media.“P. lilae” UFO1 at 30°C is shown in Figure 2. Optimal temperature and pH for growth of “P. lilae” UFO1 were determined using R2A broth supplemented with 20 mM fumarate. The range of growth temperatures was 22–37°C, with an optimum of 37°C; average generation times at 22, 30, and 37°C were 4.6, 2.9, and 1.9 h, respectively. The range of pH for growth on R2A broth with 20 mM fumarate was 5.5–8, with optimum growth at pH 7. No growth was observed at temperatures of 13°C or 42°C, or at pH ≤ 5.4 or pH ≥ 8.5.A growth curve for “D-fructose, L-fucose, D-galactose, D-galacturonic acid, D-glucose-6-phosphate, glycerol, 3-methyl-D-glucose, palatinose, L-rhamnose, α-ketobutyric acid, α-ketovaleric acid, pyruvic acid, and succinic acid. “P. lilae” UFO1 fermented the following substrates : fructose, fumarate, glucose, glycerol, lactate, mannitol, pyruvate, and yeast extract. Malate and succinate were tested but not fermented. “P. lilae” UFO1 did not grow chemoautotrophically on H2-CO2 (see Table 1).Carbon sources utilized in Biolog AN microplates were P. lilae” UFO1 was isolated from an Fe(III)-reducing enrichment by cultivation with acetate and AQDS, this “P. lilae” was not capable of respiratory growth on AQDS when 10 mM acetate was provided as the electron donor. AQDS was reduced to AH2DS only in the presence of fermentable substrates or H2 (Table 1). In the presence of 10 mM lactate, nitrate was reduced to nitrite following 1 week of incubation. As(V), NO3-, SeO42-, and SO42- were not reduced in the presence of 10 mM lactate.Although “P. lilae” UFO1 is shown in Figure 3. In the presence of 10 mM lactate, nearly 3 mM Fe(II) was produced after 1 week of incubation. Production of Fe(II) was not evident in abiotic controls. Biotic reduction of Fe(III)-NTA in the absence of lactate did not occur.The incomplete reduction of 10 mM Fe(III)-NTA by “3/2 spectra collected on a cell-free control containing ferrihydrite incubated with culture medium and H2 suggested that abiotic Fe(III)-reduction did not take place under these conditions (Table 2). The collected peak envelope is described well by the Fe(III) multiplet splitting model and is in agreement with published iron oxide spectra (data not shown). However, cell-free controls incubated with H2 + AQDS, lactate, or lactate + AQDS revealed the presence of 14.8, 26.2, and 26.0 atom% Fe(II), respectively, indicating some abiotic reduction of ferrihydrite occurred. Incubation of ferrihydrite with strain UFO1 and H2, both with and without AQDS, revealed a significant increase in the Fe(II) contribution compared to the abiotic controls. Addition of a principal Fe(II) peak at 708.4 eV for the ferrihydrite spectra (together with associated multiplet and satellite peaks) was required to complete the model (not shown). In contrast, lactate did not appear to significantly enhance reduction of ferrihydrite by “P. lilae” UFO1 regardless of the presence of AQDS.High-resolution core Fe 2pP. lilae” UFO1 under non-growth conditions. Figure 4A shows the nearly complete removal of 1 and 3 ppm Cr(VI) by strain UFO1 within 24 h when lactate (10 mM) was provided as an electron donor, whereas 5 ppm Cr(VI) decreased to an average 0.3 ppm in 26 h. Over the course of the experiment, controls containing heat-treated cells  did not exhibit significant Cr(VI) removal suggesting that sorption to cell surfaces did not contribute to the removal of Cr(VI) seen in other treatments. In Figure 4B, it is evident that Cr(VI) removal was dramatically enhanced in the presence of 1 mM AQDS. For treatments containing 3 and 5 ppm Cr(VI) with lactate (10 mM) plus 1 mM AQDS, Cr(VI) concentrations dropped to less than 0.1 ppm after just 2 h of incubation with cell suspensions of strain UFO1. There was no significant change in Cr(VI) concentrations in cell-free and heat-treated controls. In contrast to the Fe(III)-NTA results, where lactate appeared to be required for Fe(III) reduction, Cr(VI) was removed in the absence of lactate from 3 to 0.5 ppm in 24 h, which may suggest the use of endogenous carbon reserves by “P. lilae” UFO1, if removal is assumed to be the result of reduction. Others have similarly observed removal of soluble Cr(VI) by other bacterial species in the absence of exogenous electron donors (2) with a non-specific NADH oxidoreductase activity that can reduce Cr(VI) to Cr(III). In Pelosinus sp. HCF1 (P. lilae” UFO1 (see below).Soluble Cr(VI) was removed from solution in cell suspensions of “n donors , suggestsp. HCF1 , Cr reduP. lilae” UFO1 was previously evaluated for its U(VI) transformation abilities . The predominant fatty acids identified were C15:1 ω8c, C17:1 ω8c, and C15:0. “P. lilae” UFO1 had straight saturated (35.52%) and unsaturated (62.38%) chains, 6.59% C11 and C13 fatty acids, 74.87% C15 and C17. The fatty acid profile of strain UFO1 is consistent with profiles characteristic of members of the Class Negativicutes described previously (14:0 DMA and C14:1 ω7c DMA) accounted for 9.52% of the total fatty acids identified and are characteristic of anaerobic bacteria. Significant amounts of dimethyl acetals among members of the Class Negativicutes have been reported previously (The majority of fatty acids identified in strain UFO1 were straight unsaturated chains in eviously  with theeviously .P. lilae” UFO1 contained meso-diaminopimelic acid (m-Dpm) as the diagnostic diamino acid in the total hydrolysate of the peptidoglycan. Alanine and glutamic acid were also present in the peptidoglycan. Partial hydrolysis of the peptidoglycan revealed the presence of the peptides L-ala—D-glu and Dpm—D-ala. From these data, it was concluded that “P. lilae” UFO1 shows the directly cross-linked peptidoglycan type, A1γ m-Dpm-direct . The DNA G+C content of P. fermentans R7T, is 41.0 mol% . Results indicate that “P. lilae” UFO1 is phylogenetically distinct from the most closely related organisms P. fermentans R7T   with a clone detected in a pH 5, Fe(III)-reducing enrichment established with background sediments from the FRC, pH5lac302-37 (AY527741) (P. lilae” UFO1: 97% for Gly030-8A (AY524569) and 97% for Gly030-5C (AY524568). A recent paper by Pelosinus in enrichments of sediments from a United Kingdom nuclear site. Stimulation with glycerol phosphate resulted in substantial increases in bacteria closely related to Pelosinus, which comprised 33% of bacteria identified at the genus level. This work implicates Pelosinus species as having a key role in the removal of soluble U(VI) via precipitation to a reduced, crystalline U(IV) phosphate mineral, considered to be more recalcitrant to oxidative remobilization, in contaminated sediments.“tans R7T , Pelosinpionica) , and Peldefluvii . The disY527741) . AdditioY527741)  that werP. lilae” UFO1, significant inter-operon heterogeneity among 16S rRNA gene clones from “P. lilae” UFO1 was detected. Sequencing of cloned 16S rRNA gene PCR products revealed two distinct 16S rRNA gene sequences were present in strain UFO1. These differences were not due to the presence of a contaminant, as the culture was extensively purified prior to analysis , and a NiFe-hydrogenase (UFO1_2674) linked to a cytochrome b (UFO1_2673). Obviously, characterized metal-reducing Firmicutes, including strain UFO1, harbor a multiplicity of genes conferring metal detoxification ability, further extending the importance of these organisms in the biogeochemical processing of toxic metals.The draft genome sequence for strain UFO1  was dataPelosinus lilae” UFO1 represents a novel addition to a recently described and poorly characterized genus of fermentative bacteria. The most closely-related species, P. fermentans R7T, was similarly isolated from an Fe(III)-reducing enrichment; however, the enrichment was established with kaolin lenses originating from Plast, Russia -oxide, ferrihydrite. The presence of AQDS also enhanced Cr(VI) removal from solution. The AQDS-AH2DS couple has a standard potential (Eo) of -184 mV at pH 7 (42--Cr(OH)3 couple (+480 mV at pH 7)  removal in the presence of AQDS was likely due to reduction. These findings suggest that fermentative bacteria such as strain UFO1 may play a role in the reduction of humic acids, which may in turn facilitate the reduction of metallic contaminants in subsurface environments.“, Russia . This su at pH 7 , which iat pH 7) ; therefo“Pelosinus lilae” UFO1 was isolated from pristine sediments beneath Oak Ridge National Laboratory, Oak Ridge, TN, United States. Organisms with high 16S rRNA gene sequence similarity to strain UFO1 have been detected in Fe(III)-reducing  from cell suspensions , Cr(VI) and U(VI) by UFO1 suggest a potentially important role for this and similar organisms in influencing the biogeochemistry of pristine and contaminated geologic media at the ORFRC.reducing  and U(VIreducing  enrichmepensions . “P. lilAR, SC, AN, JI, and DC conducted the experiments. AR, SC, YF, DC, and TM designed the experiments. All authors contributed to the preparation of the 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.


To assess how well Caribbean regional institutions (RIs) met their commitments from the 2007 Port-of-Spain Summit (POSS) declaration on noncommunicable diseases (NCDs), and evaluate the POSS impact on the United Nations High-level Meeting (HLM) on NCDs in 2011 (2011 HLM), HLM NCD review in 2014 (2014 HLM), World Health Organization’s 2025 NCD targets (2025 WHO), and 2030 Sustainable Development Goals (SDGs) agreed upon in 2015.This study uses a method developed by the University of Toronto’s Global Governance Program to measure institutions’ compliance with commitments from a summit and the match with commitments from earlier summits. This approach was supplemented using data from published literature, primary documents, and semistructured key informant interviews to detail how and why Caribbean RIs met the 2007 POSS commitments, how the 2007 POSS commitments led to compliance, and how the 2007 POSS influenced international NCD commitments.Caribbean RIs implemented the 2007 POSS commitments better when they had more public legitimacy, when their missions aligned with those commitments, and when more resources were available to them. Implementation constraints arose from multiple, sometimes competing, interests of the decision-making and national implementing bodies of the Caribbean Community (CARICOM). Internationally, the early, expanding efforts of the POSS pioneers had an initially important but subsequently diminishing impact on the HLMs.For the Caribbean region, the Caribbean Public Health Agency should be funded to lead strengthened Caribbean RIs in coordinated action on NCDs. At the international level, the United Nations should embed NCDs in a “whole-of-global-governance” approach, monitor implementation annually, foster transregional partnerships on NCD-related themes, engage civil society, and support regular regional and global summits to enhance implementation and improvement, aimed at future HLMs on NCDs, the 2025 WHO targets, and the SDG NCD targets. In 2007, the world’s first summit dedicated to noncommunicable diseases (NCDs) was held by the heads of government of the Caribbean Community (CARICOM) in Port-of-Spain, Trinidad and Tobago. At that assembly, the landmark Declaration of Port-of-Spain: Uniting to Stop the Epidemic of Chronic NCDs was issued. The Declaration contained 27 commitments for NCD prevention and control, including reducing risk factors and improving access to preventive care . AdditioExisting studies have analyzed the preparations, production, and outcomes of the Port-of-Spain Summit (POSS) and their impacts in the short term -4. HowevThis article asks what the longer-term regional and global impacts of the POSS were, as the world’s first summit on preventing and controlling NCDs. It answers by assessing CARICOM members’ compliance with their POSS commitments, how Caribbean RIs met their summit commitments, and how the POSS influenced the United Nations High-level Meeting of the General Assembly on the Prevention and Control of Non-communicable Diseases on 19–20 September 2011 (2011 HLM), the high-level meeting of the General Assembly on the prevention and control of NCDs on 10 July 2014 (2014 HLM), and the United Nations 2030 Sustainable Development Goals (SDGs), particularly SDG3  agreed upon at the United Nations Sustainable Development Summit (SDG Summit) on 25–27 September 2015.This study uses a method developed by the University of Toronto’s Global Governance Program to measure members’ compliance with commitments from a particular summit and how well those commitments matched commitments from a previous summit -9.This analysis employs a framework first developed by George von Furstenberg and Joseph Daniels for assessing compliance with Group of Seven (G7) summit objectives, supplemented by Marina Larionova’s assessment of G7 members’ compliance with international and regional organizations’ mandates -11. For Using data collected from published literature, primary documents, and semistructured key informant interviews, the analysis also identifies the influence of the POSS on NCD-related actions taken by regional and global organizations.Bulletin of the World Health Organization, Revista Panamericana de Salud Pública/Pan American Journal of Public Health, Lancet, British Medical Journal, Global Heart, American Journal of Public Health, Health and Place, World Medical and Health Policy,Global Governance, International Organization, International Affairs, and Administrative Sciences. This was supplemented by a systematic search using the University of Toronto Libraries database for combinations of key words on noncommunicable diseases, heart and stroke, cancer, diabetes, chronic respiratory disease, Caribbean Community, summit, United Nations high-level meeting, and Sustainable Development Goals. The most relevant articles are identified in the works cited and in the references of this article.Relevant published literature was identified through scanning peer-reviewed journals on public health and on global governance. These journals included the Primary documents included those in the global summitry archives of the Global Governance Program at the University of Toronto and those provided by the Caribbean Public Health Agency (CARPHA) and key informants. A total of 50 semistructured interviews were conducted between 2010 and 2017, with current and former officials of the institutions of interest. RI responses were assessed according to raw information provided by these key informants, triangulated with and confirmed by publicly available data on specific implementing actions and, in some cases, progress reports provided by the Caribbean RIs themselves.Following standard practice, RIs were conceived as both “actors” and “frameworks for action” . They prMore specifically, CARICOM RIs’ responses were assessed according to those RIs’ speed of starting to implement each mandate, the continuity and completeness of that implementation, and the extent to which members of RIs complied with related commitments.This POSS influence was assessed in a three-step process. First, the POSS Declaration was matched with the 2011 HLM outcome document. Second, the 2011 HLM outcome document was matched with the outcome document from the 2014 HLM. Third, members’ compliance with the commitments contained in all the outcome documents was measured, using methods developed by the University of Toronto’s Global Governance Program. The assessment next traced, through key informant interviews using a snowball technique, the political and diplomatic process from the POSS to the SDG Summit in 2015, at which the SDG targets were agreed upon, using the same methods as those used for the Caribbean RIs, thus adding to works based on research done before the 2011 HLM -17.This research was conducted for the Port-of-Spain Declaration Evaluation Research Group  led by the University of the West Indies (UWI), Cave Hill campus, and funded by Canada’s International Development Research Centre on behalf of the Pan American Health Organization (PAHO) and CARICOM .The POSS Declaration issued 27 commitments that reflected the cognizance of the CARICOM heads of government of their governments’ capacity constraints and the heads’ resolve to have Caribbean RIs provide collective expertise and technical resources to facilitate compliance with those commitments.Very few studies have analyzed either Caribbean RIs’ responsiveness to the POSS commitments or the impact of these responses on CARICOM members’ compliance with those commitments. The Healthy Caribbean Coalition (HCC), a not-for-profit civil society organization comprising over 100 nongovernmental organizations committed to preventing and combatting NCDs in the Caribbean, was one of the few bodies to assess Caribbean RIs’ responses to their POSS commitments, but it did not address factors influencing responsiveness . POSDevaThe speed of responses and completeness of implementing activities varied (data available upon request). The Caribbean Food and Nutrition Institute (CFNI), the Caribbean Epidemiology Centre (CAREC), CARPHA, the Office of Trade Negotiation (OTN), the Caribbean Agricultural Research and Development Institute (CARDI), UWI, and the HCC were timely in their responses and addressed the full range of activities required to fulfill their mandates throughout the evaluation period. (CFNI and CAREC merged into CARPHA in 2013.) The Caribbean Cooperation in Health (CCH) Secretariat and the Caribbean Regional Organisation for Standards and Quality (CROSQ) fared well in their breadth and continuity; however, there was a slight lag in responding to the POSS commitments.Caribbean RI responses related to member compliance with the POSS Declaration varied significantly among the institutions and their specific institutional mandates (data available upon request). Member compliance with commitments related to the mandates of PAHO institutions, UWI, and CCH was much higher than compliance with commitments related to CROSQ and OTN; compliance requiring collaboration with these two CARICOM institutions was significantly lower.Three reinforcing factors supported the speed and ability of Caribbean RIs to undertake activities to meet their POSS mandates and related commitments: institutional legitimacy, material resources, and alignment of the institutions’ mandates with the commitments. The interests of the decision-making bodies and implementing agencies were critical to Caribbean RIs’ impact on member compliance. When the mandates aligned with those interests, Caribbean member states were more likely to adopt the RIs’ policy recommendations. CFNI was wound down in 2012, before CARPHA became operational, which perhaps affected CARPHA’s responsiveness to the POSS diet and nutrition commitments.The POSS Declaration reinforced the institutional legitimacy of existing Caribbean RIs and ascribed legitimacy to new regional institutions . This leSimilarly, the mandate issued to OTN to pursue fair trade policies legitimized its advocacy for prioritizing health in negotiating multilateral trade agreements and assessing the implications of global trade policies on controlling and preventing obesity.Caribbean RIs struggled to address the POSS Declaration commitments using existing institutional and budgetary resources. The POSS did not authorize new monies to fund the mandates or create implementation mechanisms. Subsequent strategies neither assigned nor identified additional funding for these institutions. The ability to utilize existing resources or access additional funding was crucial. CAREC and CFNI were financed through PAHO’s regional budget allocations and extrabudgetary projects. OTN could use existing in-house technical resources, and the HCC successfully attracted regional funding  and inteTo leverage the overarching structure of CARICOM to support CARPHA’s mandate, CARPHA developed platforms that provided sustained involvement with relevant RIs . CARPHA CARPHA also encouraged dialogue between regional decision-making bodies . In collWhen the assigned commitments were aligned with Caribbean RIs’ existing missions, the response speed was not hampered by the extra effort that often accompanies institutions with assigned mandates acting outside their core missions. The CFNI, CARDI, CAREC, CCH, and OTN were already engaged in activities that fell within the scope of their 2007 POSS Declaration mandates and related commitments. OTN was already exploring the intersection of health and trade and reviewing the use of trade policies to address NCDs. The CCH Secretariat had an established regional mechanism for coordinating stakeholder consultation and developing regional health frameworks and strategic plans.POSS also had an early, significant influence on the global governance of NCDs, through the 2011 HLM, the 2014 HLM, and the 2015 SDG Summit, although that influence progressively diminished. The 2011 HLM, held only four years after the POSS, was the second-ever United Nations summit devoted to health . The POSThe 2011 HLM outcome document had only one direct reference to the POSS, but the document put the reference in its preamble’s paragraph, which expressed United Nations appreciation for various regional initiatives to control and prevent NCDs. The 2011 HLM’s 205 precise, future-oriented, politically obligatory and binding commitments substantially matched the 27 POSS commitments . A majorReciprocally, a majority (59%) of the POSS commitments were reflected in the 2011 HLM ones at least once . HoweverUnited Nations members’ compliance with 2011 HLM commitments in the first year after that HLM shows an influential “POSS” push through to 2012 (data available upon request). Of the eight commitments initially assessed for compliance, the six with a matched POSS precursor commitment  had higher compliance by the United Nations’ 40 Western Hemisphere members and by the CARICOM members specifically (data available upon request). If the POSS parent had high first-year compliance from CARICOM members, its matched 2011 HLM offspring had higher first-year compliance too (data available upon request).More specifically, the six 2011 HLM commitments with a POSS parent had an average compliance of +0.27 by Western Hemisphere members, compared to −0.11 for the two commitments without a parent (data available upon request). The increase was even higher for the CARICOM members. However, there was also a similar increase among CARICOM members for commitments without a POSS match, suggesting a more general POSS participation effect.Among the 13 2011 HLM commitments subsequently assessed for first-year compliance, the 9 commitments with POSS parents had average compliance +0.27 higher among CARICOM members than among the other United Nations members of the Western Hemisphere (data available upon request). For the remaining 4 commitments, the average compliance for CARICOM members was −0.07 lower than for the other Western Hemisphere members.This POSS influence was enhanced by higher first-year compliance from CARICOM members with their parent POSS commitments (data available upon request). The three POSS commitments with the highest first-year compliance, averaging +0.14, had their three matched 2011 HLM offspring secure first-year compliance of +0.47. The three POSS commitments with the lowest compliance, averaging −0.49, had their three matched 2011 HLM offspring secure first-year compliance of only +0.09.Assessing CARICOM members’ compliance with their 27 POSS commitments in annual intervals, as measured by the implementation of 14 indicators set out by the CCH in Phase III of the Regional Caribbean Cooperation Strategy, suggests a sustained positive POSS push (data available upon request).  – “Investing in Health for Sustainable Development.”)The political process through which the regional POSS shaped the United Nations’ global NCD regime began by producing POSS with a global vision. The first phase began in 1986, when CARICOM health ministers approved the CCH’s first initiative in which NCDs were a priority. The CARICOM heads of government then approved a regional approach to NCDs at their meeting in 2001 in Nassau, Bahamas. In July 2006 they approved “a special regional consultation” hosted by Trinidad and Tobago, and in February 2007 upgraded it to a regional “summit,” also held in Trinidad and Tobago. The POSS was held in Port-of-Spain in September 2007.The initiative to produce POSS had begun with three members of the Caribbean Commission on Health and Development, some of whom sought a CARICOM summit as a pathway to a United Nations one . EssentiThe second phase started right after POSS, when CARICOM heads of government were told that they needed to take their work further. With PAHO’s encouragement, they injected NCDs into their broader Commonwealth Heads of Government Meeting and the Summit of the Americas, both hosted in Port-of-Spain in 2009. Within the Americas, other regional blocs in Central and South America issued declarations on NCDs .At the United Nations, key individuals from the Caribbean lobbied the United Nations secretary general to hold a high-level meeting on NCDs. They drafted the authorizing resolution in a way that aligned with POSS to benefit all regions.In 2007, the World Health Organization (WHO) began crafting a global plan on NCDs. PAHO/WHO members soon recognized that preventing and controlling NCDs required a political solution involving the highest level of policymakers, namely heads of government. The Caribbean diplomatic missions in Geneva and New York, delegations from Caribbean countries attending WHO and United Nations meetings, and the Norwegian and Russian representatives pushed to pass resolutions at the annual World Health Assembly and at the United Nations, calling for a high-level meeting on NCDs in 2011. Each of the six WHO regions met in the lead-up to the HLM. The first Global Ministerial Conference on Healthy Lifestyles and Noncommunicable Disease Control, held in Moscow in May 2011, provided additional support.During the negotiations on the 2011 HLM outcome document, disagreements arose over targets and indicators, financing, WHO or United Nations leadership, the use of WHO’s “best buys,” and the addition of mental health to the four major NCDs of cancer, diabetes, respiratory disease, and cardiovascular disease. Some United Nations members disagreed with using the term “best buys” but referenced the WHO text that listed those measures. Influential individuals from the Caribbean helped to focus the 2011 HLM on the big four NCDs, as POSS had done. Those individuals also shaped other outcomes in POSS-consistent ways.In the third phase, creating the subsequent 2014 HLM, the direct Caribbean contribution diminished, even though Trinidad and Tobago led the Group of 77 developing countries at the United Nations . AlthougThe next United Nations HLM on NCDs occurred at the United Nations in New York on 27 September 2018. The declaration from that meeting was titled “Time to Deliver: Accelerating Our Response to Address NCDs for the Health and Well-Being of Present and Future Generations.” It emphasized the need to mobilize further political action at the national and global levels to prevent and control NCDs. The next United Nations HLM on NCDs is scheduled for 2025.The fourth phase, securing the SDGs with NCDs included, relied even more on WHO , 33. WHOThe result was the 2015 SDG Summit’s inclusion of an NCD target (reduce premature deaths from NCDs 30% by 2030) in SDG3 on health, as well as the identification of health-supporting measures in other SDGs. The concepts of health throughout the human life cycle and moving from an illness framework to a wellness one were also advanced.This analysis aimed to assess how Caribbean regional institutions met their commitments from POSS, the first political summit on NCDs. The study found that public legitimacy, mission alignment with POSS, and resources enhanced RI compliance. Furthermore, when RI commitments aligned with national interests, CARICOM member-state compliance with the POSS commitments was much higher.When Caribbean RIs’ overall mandates aligned with the interests of respective national decision-making bodies and implementing agencies, member-state compliance with the commitments in the POSS Declaration was much higher. In addition to two Caribbean RIs (CARPHA and the CCH Secretariat), two PAHO decision-making bodies (CFNI and CAREC) were composed of Caribbean health ministers. Similarly, the national implementing bodies of those RIs consisted of health officials who shared similar health interests. These actors played a key role in convening the 2007 POSS and were intimately aware of the directives issued in the POSS Declaration.In contrast, the decision-making body and implementing agencies of OTN and CROSQ are composed of trade ministers and officials accountable to various stakeholders. The processes of those bodies were often stymied as officials sought to resolve competing interests. An example is the CROSQ’s response to its mandate to standardize effective tobacco warning labels. Controlling tobacco use is one of the commitments in the POSS Declaration. It is also a primary mandate of the CROSQ when it comes to standard-setting and quality control. During the CROSQ consultation process, Trinidad and Tobago tobacco manufacturers vigorously opposed initial schedules for rotating health warnings because they felt such warnings would increase their cost of doing business. Some national health-based organizations rejected the tobacco warning labels because they were not far-reaching enough.This analysis highlights the value of funding CARPHA to lead strengthened Caribbean RIs to prevent and control the rising burdens of NCDs. The analysis further shows the value of embedding NCDs in the biggest, broadest, whole-of-global-governance approach at the United Nations and of engaging the private sector, civil society, and mass publics. It also suggests the value of annual compliance monitoring and regular summits to review, reinforce, and improve implementation, now aimed at the 2025 HLM on NCDs and the 2030 SDGs review conference.With the global and regional burden of NCDs still rising rapidly, but with NCDs as only one of the 169 targets in the SDGs, new actions from and in the Caribbean are needed now. These could include regular CARICOM summit sessions on NCDs, interministerial council meetings to review and improve implementation, a streamlined monitoring mechanism benefiting all key actors, the addition of NCDs to the agenda of the European Union’s Latin America and the Caribbean meetings, and continuous comprehensive assessments of compliance with NCD-related commitments from the POSS, CARICOM heads of government meetings, HLMs, and the SDGs, with a focus on the fiscal, economic, and environmental benefits that compliance brings.To show continued global leadership, the CARICOM Quasi Cabinet, the Council for Trade and Economic Development, and the Caribbean finance ministers and foreign ministers should use the intersessional conferences and heads of government meetings to take key decisions on smoke-free public spaces and mandatory food labeling as human rights and consumer empowerment issues. They should also adjust the public tax structure to reduce the consumption of tobacco, alcohol, and sugar-sweetened beverages by Caribbean citizens. To accelerate action, more research on implementation is needed, particularly focusing on barriers to the uptake of evidence, political feasibility, and the building of all-of-society alliances.Research conducted for this analysis was funded by the International Development Research Centre.RPSP/PAJPH or PAHO.Authors hold sole responsibility for the views expressed in the manuscript, which may not necessarily reflect the opinion or policy of the


Biomedical publications listed in Medline were analyzed based on publisher’s location [1] and first author’s country of origin . In the present analysis I wished to determine the languages of biomedical publications and the publishers’ locations.