A crack caused by shrinkage could remarkably increase the permeability, heavily deteriorate the durability, and heavily deteriorate the service life of a concrete structure. However, different forms of thermal shrinkage can be predicted by directly applying a temperature load on a node. The prediction of moisture-induced stresses in cement-based materials by using the common finite element method (FEM) software is a big challenge. In this paper, we present a simple numerical calculation approach by using the proposed coefficient of hygroscopic expansion (CHE) to predict the moisture-induced deformation of concrete. The theoretical calculation formula of the linear CHE (LCHE) of cement-based material was deduced based on the Kelvin–Laplace equation and the Mackenzie equation. The hygroscopic deformation of cement mortar was investigated by inversion analysis; based on the results, the LCHE could be determined. Moreover, a case analysis of the application of LCHE to concrete is also conducted. The simulated results of concrete shrinkage were close to the experimental ones. As a whole, it is feasible to predict the drying shrinkage of concrete through simple calculation by using the proposed LCHE, which is also beneficial to the direct application of moisture loads on nodes in finite element analysis (FEA). The durability of concrete materials and structures is strongly influenced by cracks that are mostly induced by poor volume stability, and factors such as freeze–thawing, carbonization, alkali–aggregate reactions, chemical attacks, and rebar corrosion all affect durability . The craMoisture transport plays a main role in the durability and serviceability of cement-based materials ,8. It isIn real engineering structures, the deformation and cracking performance of concrete results from the coupling effect of environmental temperate, humidity, and structural loads. It is very important to investigate the hygro–thermo–mechanical deformation cracking performance and mechanisms of concrete. A number of studies have been published on the coupled hygro–thermo mechanical deformation of concrete, with hygro–thermal transference and induced deformation being investigated at high temperatures to analyze the behavior of concrete in fire ,13,14. SSimilar to the effect of ambient temperature on the expansion of concrete samples, during the process of humidity exchange (moisture transfer), there is also a moisture gradient between the “layers” at different distances from the humidity exchange surface. Additionally, this gradient generates a stress differences under the mutual restraint between the layers. Therefore, by referring to the coefficient of thermal expansion (CTE) of materials, it is feasible to propose the concept of the coefficient of hygroscopic expansion (CHE) of cement-based materials. We believe that the application of the CHE to the FEA of calculating humidity effects will be beneficial in solving the difficult problem of calculation the deformation of humidity distribution. This coefficient should also be able simplify the calculation process of humidity deformation. At present, the CHE is mainly used to evaluate the moisture expansion and interfacial stress performance of ceramic tiles, clay blocks, and polymer composite materials ,22. It i0, where M0 is the moisture absorption rate unit) can be calculated as follows: One measures the change of expansion after the moisture absorption rate unit and then divides that change by the initial length of the sample to obtain the CHE.According to the test methods of ceramic tiles—Part 10: Determination of Moisture Expansion (ISO 10545-10)—the initial length of the ceramic brick sample is measured twice (the second time is measured after 3 h) after being reheated and cooled, and then the sample is immersed in boiling water for 24 h. Afterwards, it is cooled down to room temperature, and its length is measured after 1 and 3 h to get the average value. The ratio of the difference between the two average values to the average initial length of the sample is the wet expansion of the ceramic brick. For polymer composites, the CHE , βsh is the LCHE (με), ΔV is the volume change of the specimen (m3), ΔL is the length change of the specimen (m), Δφ is the relative humidity change (%), V is the volume of the specimen of material (m3), L is the length of the specimen of material (m), and εsh is the linear strain .Similar to the definition of the CTE ,24,25, tdεsh is the change of shrinkage strain (με) and dφ is the change of the relative humidity (%). Abbasnia et al. also considered that shrinkage, as one property of a material, can be described by an increment relation, which is expressed as the product of the shrinkage coefficient and the relative humidity of a capillary. This relation can be expressed as [shk is the shrinkage coefficient (με) and f(φ) is the function of relative humidity of pores.In 2006, Gawin et al. proposed that the shrinkage strain of concrete can be assumed to be directly proportional to the change of relative humidity through a phenomenological approach found in Professor Bazant’s research; this approach can be expressed as :(3)dεsh=essed as :(4)εsh=kThe above viewpoints and formulas confirm the feasibility and practicability of defining the wet expansion coefficient of concrete. It should be pointed out that the capillary tension theory and the Kelvin–Laplace formula are not applicable when the relative humidity is lower than 45%. Therefore, the application relative humidity (RH) range of the CHE proposed in this paper is 50%–100%.There is a static balance between the attraction and repulsion of pore water pressure to microstructures in hardened cement-based materials in the absence of self-drying or external drying. When drying occurs, the solution pressure in pores decreases due to the change of the capillary meniscus in the unsaturated pores, the static equilibrium is broken, the water vapor diffuses from the inside of the material to the surface, and more pores water is forced to evaporate to maintain equilibrium. It is generally believed that macropore water is lost first, and once the pore diameter reaches 50 nm, the capillary meniscus and micro shrinkage stress appear  and the φ is relative humidity (με), R is the universal gas constant (8.314 J·mol−1·K−1), T is the temperature in kelvins (K), p is the negative pore fluid pressure (Pa), and mv is the molar volume of water (m3·mol−1).From the point of view of mechanical equilibrium, the relationship between pore pressure and meniscus curvature satisfies the Laplace equation ,30. The p is the average hydrostatic pressure change , S is the saturation factor , K is the bulk modulus of the porous solid (GPa), and K0 is the bulk modulus of the solid skeleton of the material (GPa).According to Mackenzie’s study, for a fully saturated porous medium, if the solid skeleton is linear elastic, the relationship between the change of mean hydrostatic pressure and the linear strain is as follows ,33,34:, Vac/V is the volume fraction of the aggregate in concrete (or cement mortar).As is known, the aggregate accounts for a large part of concrete, and its volume is relatively stable. The shrinkage deformation of concrete mainly comes from the shrinkage of hardened cement paste, and when cement stone shrinks, aggregates limit the shrinkage of cement stone and then reduce the shrinkage effect of concrete. Therefore, the influence of aggregates and their force cannot be ignored in the analysis of the influence of average hydrostatic pressure (or pore hydraulic pressure) on the volume deformation of concrete ,34,35. Op can be expressed as:i indicates the start status and the subscript f indicates the end status.For partially saturated porous solids such as cement-based composites, the average hydrostatic pressure in pores can be replaced by pore fluid pressure. Thus, ΔFurthermore, the relation equation between humidity strain and the relative humidity of cement-based materials can be deduced and expressed as:φ, the expression of the LCHE can be obtained theoretically.By dividing Equation (9) by Δβsh is constant, the LCHE is still not merely related to the relative change of relative humidity.It can be seen that humidity causes the deformation effect of a cement composite. When the CHE, similar to the CTE, is used to describe the deformation effect, the relationship between the wet deformation, the dry deformation, and the LCHE is different from that between the thermal deformation and the LCTE, and its form is more complex. Even if the first three items’ expression of K = 25 GPa, K0 = 26 GPa [Vac/V = 0.65, S = 1, iT = fT = 20 °C, i =φ 100%, and f =φ 50%, the calculated LCHE is then:0 means 1% change of relative humidity and με means 10−6.According to the above formula, for a certain saturated concrete material during a constant temperature drying process, when the parameter values are = 26 GPa ,36, Va/Vfφ to 60%, 70%, 80%, and 90%, we can get the corresponding LCHE values of, respectively, 18.6, 20.2, 21.7, and 23με/φ0. Equation (10) is also applicable to cement mortar after changing the value of the volume fraction of the aggregate in mortar.By changing the value of Ayano and Wittmann proposed an empirical formula for the relationship between the dry shrinkage and relative humidity of mortar and concrete based on the moisture distribution and shrinkage test results of cement-based materials .Mortar:0, which is very close to 16.8με/φ0 calculated according to Equation (10).According to Equation (12), when the relative humidity is reduced from 100% to 50%, the drying shrinkage of concrete is 815.2 με. The corresponding LCHE can be deduced as 815.2/(100−50) = 16.3 με/φ0, respectively. These results are very close to those of Equation (10), as proposed in this paper. Therefore, it is feasible to calculate the LCHE by the proposed theoretical formula of Equation (10).When the relative humidity of concrete drops to 90%, 80%, 70% and 60%, the LCHEs of concrete can be calculated as 24.4, 20.5, 18.5 and 17.2 με/φ0.According to Equation (11), when the relative humidity is reduced from 100% to 50%, the drying shrinkage of mortar is 1148.5 με. The corresponding LCHE can be deduced as 1148.5/(100−50) = 22.97 με/φα is the Biot coefficient of concrete, χws is the fraction of skeleton area in contact with water, cp is the equilibrium capillary pressure (Pa), ρw is the water density (kg·m−3), sK is the bulk modulus for solid phase , TK is the bulk modulus for skeleton , wM is the molar mass of water (1.8 × 10−3 kg·mol−1), R is the universal gas constant , and I is the tensor unit of the second-order.In the research of the hygro–thermo–chemo–mechanical modeling of concrete by Gawin et al. , the relα and cp in the expression of εsh as expressed in Equation (13), εsh can be derived and expressed as:By substituting Vac/V) and the saturation factor (S) are considered in Equation (9), while the area fraction of the wetted solid skeleton (χws) is considered in Equation (14). Equation (14) describes the linear shrinkage strain of cement-based materials at a constant temperature.Equation (14) is very similar to Equation (9), which was firstly derived and proposed by us. The differences are that the influence of the aggregate volume fraction , which is consistent with the proposed theoretical calculation formula of the LCHE, as expressed in Equation (10). Therefore, Equation (14) also can be used to prove the rationality of the LCHE and its calculation method proposed in this paper.Similar formal equations can also be derived by dividing Equation (14) by ΔThe theoretical derivation method to determine the LCHE of cement-based materials has clear physical significance (see Equation (10)), but it is inconvenient to use this equation when the internal humidity field is hard to determine .Besides the theoretical derivation, the LCHE also can be determined by a test. However, the measure of the internal humidity of materials is relatively complex. Moreover, it may take a long time to determine the deformation of a certain size of materials after the materials are completely balanced with different environments during testing, especially when the relative humidity of the environment is low. Therefore, the inversion analysis method can be considered for the determination of the LCHE of cement-based materials ,39.Here, the inversion analysis method mainly refers to a method in which the parameters required in the concrete simulation are not obtained by measurements in the actual field or laboratory; rather, they are obtained by using some ambient temperature and humidity or deformation measurement values to infer the relevant parameters, which are then applied to the whole simulation calculation process. When some parameters are difficult to obtain through testing or it is difficult to accurately reflect the actual situation, the inversion analysis is helpful for grasping the parameters that are needed for simulation and for more accurately calculating the physical and mechanical properties of concrete. In addition, this method can be used to calculate the required parameters in complex and unstable environments.For this paper, drying shrinkage tests were performed, and the distance change between steel needles was measured and analyzed. The cement mortar specimen was cylindrical disk with a height of 50 mm and diameter of 300 mm, and steel needles with different distances from the center  of the test piece were embedded on the upper surface so that the Vernier calipers could be used to measure the initial gauge distance and the distance change on different days. Considering of the symmetry, the probe of the steel needle was arranged with equal spacing along a certain radial direction, as can be seen in The drying shrinkage experiment results were used to be compared with those from the drying shrinkage experiments to validate the constructed model and the obtained material properties.In inversion analysis, the finite element model, as the forward model, was created based on thermal–mechanical interaction with the transient analysis. The COMSOL Multiphysics software was used for the inversion analysis of the LCHE of cement-based materials.Because moisture distribution cannot be directly treated as moisture stress and deformation in COMSOL, a finite element model was created based on thermal-structural interaction with the transient analysis. In this coupled multi-physical model, the moisture diffusion in the mortar specimen was modeled as heat transfer, and the drying shrinkage behavior was modeled as thermal expansion. Thus, the moisture diffusion coefficient was defined as the thermal conductivity in the analysis. Based on that, the uncertain parameters of moisture expansion and moisture transfer on the concrete surface could be determined by inversion analysis. The model of specimen was meshed by using a tetrahedron element through the free tetrahedral method of COMSOL, as can be seen in The mortar specimen was symmetrical, and the boundary conditions of that for moisture diffusion model are shown in −2s−1), φs is the relative humidity on the surface (%), φen is the ambient relative humidity (%), f is the surface moisture transfer coefficient of mortar , and mkD is the diffusion coefficient of mortar (kg·m−1s−1).The boundary around symmetry axis was naturally assumed to be humidity insulation, and the bottom boundary was also approximately regarded as humidity insulation due to the fact that the moisture exchange coefficient of the epoxy coating on the bottom was very small. Ignoring the impact of water evaporation through the bottom side of the specimen was beneficial for the simplification of the analysis. The upper surface and the outer side of the circular specimen were assumed as the third kind of boundary condition (convection type), which is described by Equation (15).The boundary conditions of the mortar specimen for mechanical model did not need to be defined because the specimen in the experiments was in the condition of free shrinkage.The cement mortar specimens were cured in a standard curing room for 28 days, and then they were put into a closed space with a relative humidity of 50%. Therefore, it was assumed that the internal relative humidity was 100%, that is the initial relative humidity was 100% when t = 0 on the first day of the test.In this inversion analysis, the finite element model established by COMSOL was a forward model. The optimization program was compiled according to the principle of least square method, and the interface with the optimization program code written by the MATLAB program was established. ijE is the i-th radial strain on the j-th day according to drying shrinkage test, ije is the i-th radial strain on the j-th day according to the FEA results, n is the numbers of equidistant measuring points from the center of the specimen to the circumference of the surface in the test, and m is the drying duration of specimen in the experimental moisture and heat conditions.The Gauss–Newton algorithm was adopted in the optimization program. The LCHE and the surface moisture transfer coefficient were the two variables in the optimization code. The objective function can be defined as:The LCHE and the SMTC were assigned a value in each iteration cycle, and then the forward model was called and solved. Finally, this model was replaced with the objective function. When the objective function value was small enough, the finite element calculation results and experimental results were optimized, and then the inversion values of the LCHE and the surface moisture transfer coefficient were obtained.Based on the results of the drying shrinkage of cement mortar specimens at different ages under 50% relative humidity, the LCHE and the SMTC were estimated by the above inversion analysis process. The curve fitting results are shown in 0, and the SMTC was 6.04 mm/d—these values were obtained by inversion analysis. The LCHE of 21.4 με/φ0 was close to that of 22.97 με/φ0, which calculated based on Equation (12), as proposed by Ayano and Wittmann [The LCHE of the cement mortar was 21.4 με/φWittmann . As suchAs shown in In the drying shrinkage test of concrete, the specimen size was 100 × 100 × 400 mm, the deformation probe was buried on the upper surface of the specimen, the standard curing was 3 d after formwork removal, and the specimen was placed in a constant temperature and humidity chamber  for the length change and water loss test, as depicted in The water loss and shrinkage of three groups of specimens  at different ages were measured and recorded for next analysis. The measured water loss rate of concrete is shown in 0, as calculated with Equation (10), was used for concrete, and the shrinkage value was simply calculated according to Equation (2).The internal relative humidity of the concrete was calculated according to the measured water loss rate of concrete, and these results are shown in The calculated value that was found by using the CHE and the measured concrete shrinkage value is shown in The calculated value based on the LCHE in The uncertainty of the experimental and calculating shrinkage of concrete can be analyzed by comparing the calculated values (CV in short) with the average experimental results (AER in short) at the same age; that is, the uncertainty can be found through the following: (CV – AER)/AER × 100%. For our experiments, the maximum, the minimum, and the average deviation were 16.1% (at the age of seven days), 0.2% (at the age of 132 days), and 8.8%, respectively.In this article, the concept of the coefficient of hygroscopic expansion (CHE), which refers to the expression of the coefficient of thermal expansion (CTE), of cement-based materials is presented for the convenience of simulation calculation by using common FEM software and engineering applications.The theoretical calculation formula of the linear coefficient of hygroscopic expansion (LCHE) of a cement-based material is deduced based on the Kelvin–Laplace equation and the Mackenzie Equation , as well as from the consideration of the volume fraction of the aggregate, the saturation factor, the average hydrostatic pressure change resulting from relative humidity variation in porous materials. Our obtained value of the LCHE of mortar and concrete that was calculated by the proposed formula was close to that in relevant references.The theoretical derivation method to determine the LCHE of cement-based materials has clear physical significance, but it is inconvenient to use because it is sometimes difficult to determine the internal humidity field . The inversion method can be used to obtain the LCHE and the surface moisture transfer coefficient of a cement-based material. Thus, the necessary parameters can be obtained for the deformation simulation analysis of cement-based materials without a lot of tests. The experimental shrinkage of concrete is similar to that of FEA analysis because the moisture diffusion in a mortar specimen can be modelled as heat transfer in the COMSOL software, and this model can use the LCHE for inversion analysis.A case analysis of the application of the LCHE was also conducted in this article for evaluating the applicable of the proposed CHE of concrete. The simulated results were close to experimental ones. Thus, it is feasible to calculate and predict the drying shrinkage of concrete through simple calculation by using the LCHE.


To study antibiotic use in livestock in a temporal context with the development of antimicrobial resistance, long-term changes in antibiotic use must be mapped and their possible causes must be explored. Therefore, the present work assesses the changes in antibiotic use over time in German livestock husbandry. In addition, factors associated with antibiotic use were analyzed to identify possible strategies for further reducing antimicrobial usage. For 2011, 2013 and 2014, antibiotic usage data were collected and examined within the VetCAb project. Three hundred participating pig holdings provided information on their antibiotic use based on obligatory application and delivery forms (ADFs) filled in by their veterinarian as well as information on their current stabling capacities for each production type held. Data on sow, piglet, weaner and fattening pig holdings were described separately, using the semi-annual treatment frequency (TF) to measure antibiotic consumption. Multiple linear mixed models were used to investigate the effects of time, farm size, region and farm management category on the treatment frequency. The study yielded significant time changes with p-values below 0.001 in antibiotic administration with a decreasing median TF in piglets from 3.8 in the first half of 2011 (IQR = 1.1–10.6) to 1.7 in the second half of 2014 (IQR = 0.2–4.5) and in fattening pigs from 5.1 in the first half of 2011 (IQR = 0.2–15.4) to 0.7 in the second half of 2014 (IQR = 0.1–6.7). Meanwhile the TF fluctuated between 8.2 and 12.2 in weaners during the observational period (IQRs between zero (lower quartile) and 37.9 (upper quartile)). Piglet, weaner and fattening pig holdings belonging to the upper third of the holdings in size used significantly more antibiotics than the other holdings investigated. Particularly for weaner and fattening pig holdings, a higher TF was noted for farms without breeding units. The region was only a significant factor in weaners. In conclusion, for 2011, 2013 and 2014, the present study shows a clear reduction in antibiotic treatment frequency in German pig holdings. In addition, the association with various factors such as herd size and farm organization on the antibiotic usage frequency is indisputable. Therefore, these factors should be included in monitoring systems and considered when evaluating intervention measures. Knowledge of antibiotic use is necessary for containing of antimicrobial resistance. In 1998, the EU invitational conference, "The Microbial Threat", issued recommendations on how to combat the increasing threat of developing antimicrobial resistance . In 2000In recent years, various systems have been developed worldwide to map the quantity and frequency of antibiotic use in veterinary medicine. In Germany, one of these monitoring systems was developed within the VetCAb (Veterinary Consumption of Antibiotics) project, which was the first project to publish representative data on antibiotic use in German livestock husbandry. In 2007 and 2008, the VetCAb feasibility study was conducted to determine whether representative monitoring of antibiotic consumption in Germany is feasible, which data can be used as a basis and how the data collection can be organized. This study’s results were published by Merle et al. , 10. TheCurrently, the results from various monitoring systems show substantially reduced antibiotic use in German livestock husbandry –15, as wTo analyze the temporal trend in more detail, the present work focused on the change in antibiotic usage over time in German livestock husbandry, investigating the years 2011, 2013 and 2014. Since some publications have shown that various factors influence both disease incidence –24 and aThus, in the present work, the influences of temporal trends, farm size, farm category, region and the veterinarian supervising the farms on the treatment frequency are considered via regression models.The VetCAb sentinel study is a longitudinal extension of the cross-sectional VetCAb pilot study  and dataEvery participant (farmer or veterinarian) provided information on antimicrobial substance application and/or delivery, including information on the delivery/application date, number of animals treated, name and amount of the antibiotic drug used, the medical indication and the treatment duration. Because documenting this information is mandatory for farmers and veterinarians in Germany within a five-year liability period, this information can be obtained retrospectively from the application and delivery forms (ADFs) in farming practice. Data were exported from the veterinarian’s software system, the database of the company "QS Qualität und Sicherheit GmbH", who run a private monitoring system in Germany, and from manual data entry within the study system. Furthermore, farmers provided the number of livestock places for every production type kept.As in the pilot study, all participants provided consent to use their data for this study, given that all personal data on the pig holding farmers and veterinarians were pseudonymized, as per the privacy statement given to each participant.All data are transferred manually or imported into a database. Interfaces to several official and private computer systems containing antibiotic use data are integrated in the system. The database is based on the open-source relational database system, MySQL and was designed exclusively for this project. Plausibility checks for completeness and pharmacological plausibility are performed during data input and obvious incorrect entries are intercepted. Subsequently, the dataset is also checked in detail regarding different focuses: Farms without antibiotic use and farms with unusually high treatment frequencies (TFs) are checked for correct information. Missing or incorrect information is revised and, if obtainable, corrected or excluded from the analyses.In this survey, four production type groups are considered: sows (averaging 200 kg), suckling piglets (averaging 4 kg), weaners (averaging 15 kg) and fattening pigs (averaging 50 kg). The average weights were used per the pilot study . Group aThe evaluation focuses on calculating the number of drug applications :farmsize–29. The This calculation is consistent with those used by other authors , 31; howIn this analysis, the number of livestock places is used as the population at risk to calculate the TF, i.e., the population size refers to the possibility of keeping animals rather than the number of animals kept , 26. As To study the association of various factors with antibiotic use, a multiple linear regression model is performed separately for each defined production type group separately using TF as the outcome. For this purpose, a right-trimmed data set was used to guarantee robust model estimators, where the top 1% of TFs are excluded .The explanatory variable set in each model contains "Time", "Farm size", "Farm category" and "Region" as fixed factors. Due to the hierarchical structure, the variable "Veterinarian" is included in the model as a random factor. To describe "farm size", holdings are categorized into three groups by means of the 33%- and 67%-percentile of the number of livestock places per holding for 2011. The factor "Farm category" is based on the type of production type groups held per farm. Category "Breeding" comprises holdings with sows and piglets only, "Fattening" comprises holdings with weaners and/or fattening pigs only, and the category "Combined" holdings comprises weaners and/or fattening pigs combined with sows and piglets. The category "Changer" represents the holdings that stops keeping one group, kept an additional group or changes the production type group kept over time during the observational period . For the factor, "Region", the examined animal husbandry collective is divided into geographical areas based on agricultural structures in Germany .Antibiotic use is measured twice yearly, resulting in up to six repeated measurements per holding. Mixed models are used for the analyses to account for the hierarchical data structure , 36. BecThe analyses were performed using the procedures GLIMMIX and MIXED in SAS, version 9.3, TS level 1M2 . To describe the influencing factors’ effects on the TF, the back-transformed estimators of the least-squares means with their associated 95% confidence intervals are considered for each category of factors. F-tests are used to assess the statistical significance of the fixed effects, considering p-values below 5% as statistically significant. The impact of the veterinarian random effect is analyzed using a likelihood ratio chi-square test comparing the full model with the reduced model, thus omitting the hierarchical level.In total, 51 311 ADFs from participating pig farms were analyzed. For weaners and fattening pigs, the median was 4 antibiotic substance prescriptions per holding biannually (IQR = 1–13 prescriptions per holding for weaners and IQR = 1–10 prescriptions per holding for fattening pigs), while for sows and piglets the median were 6 and 7 prescriptions per holding (IQR = 2–14 prescriptions per holding for sows and IQR = 2–16 prescriptions per holding for piglets), respectively.The number of participating holdings within the analyses increased over time. In the first half of 2011, 755 holdings were integrated into the evaluation, and 1 102 holdings were analyzed in the second half of 2014. The population composition changed only slightly relative to "Farm size", "Farm category" and "Region". Sow, piglet and weaner holdings comprised approximately 20% of these holdings each, while fattening pig holdings comprised approximately 40%. The increased number of evaluable fattening pig holdings per half-year was slightly more than that of other groups see .To describe the data basis of further statistical analyses, To improve the statistical significance of the data Tables During the observational period, significant changes occurred in the TF among all groups; however, for sows, the mean TF values estimated via the model remained constant between 0.7 and 1.1. For weaners, the mean values are estimated between 14.7 and 23.1. Although the p-value shows a global statistical significance, no general trend is observed. In contrast, the estimated means are significantly reduced in the piglets and fattening pigs."Farm size" has a significant impact on the TF in all models. The estimated TF means increased with increasing size. For all groups in the category, "Upper third", the estimated mean is at least twice as high as for the "Lower third".The factor "Region" has no significant impact on any group’s TF, except in the weaner model, since the category "East" has a nearly four-fold higher estimated mean (39.0) compared with the "Northwest" and "Middle" regions (11.4).The factor "Farm category" significantly affects the TF in piglets, weaners and fattening pigs, while the sow model is unaffected. In piglets, the model estimated similar means in the categories, "Breeding" and "Combined", at 2.6 and 2.5. The category "Changer" has a significantly higher estimated mean of 4.2. The estimated means of the weaners and fattening pigs in the category "Fattening" are significantly higher (25.8 and 4.6) than in the categories "Combined" (13.7 and 3.1) and "Changer" (17.7 and 33.1).In investigating the effect of veterinarians, values below 0.05 were observed for all p-values in the likelihood ratio test for each group model. This indicates that models addressing the veterinarian clusters fit the data better than models omitting the random veterinarian effect.A sensitivity analysis to investigate the results’ stability was performed by omitting the cases where one veterinarian ID is connected with only one farm ID (data not shown). The analysis showed no changes in interpreting of the p-values that assessed the fixed effects and the veterinarian random effect for all group models.This longitudinal study used data from mandatory ADF documentation in Germany. Veterinarians and farmers participated voluntarily in a panel study and provided data from 2011, 2013, and 2014. Based on the calculated semi-annual TF for each pig holding, the influence of various factors on antibiotic consumption on pig farms was analyzed, using regression models. This study’s main achievement is observing a cohort of pig holdings over several years.This study is a longitudinal extension of the cross-sectional VetCAb project. Van Rennings et al.  showed tThe data presented here are based on voluntary participation, thus carrying the risk of selection bias, or migration bias in longitudinal studies. The true antimicrobial use may have been higher and the reduction less pronounced than that in the presented data. However, the TF range results suggest that both selection bias  and migrAdditionally, a bias due to ADF misallocation must be discussed. Using ADFs as data sources risks assigning the ADFs and antibiotic treatments to the incorrect production type groups. The group designations were not standardized, and were often used in colloquial speech for the ADFs, resulting in the allocations being ambiguous. Specifically, the term "weaner" has various meanings in veterinary and farming practice in Germany. Therefore, an exalted misallocation frequency is possible; however, we assume that veterinarians will define production types homogeneously by adhering to the Medicinal Products Act, so that this effect will decrease over the years.In this study, antibiotic use is measured by the treatment frequency calculated based on the nUDD. Most other studies on antibiotic consumption in veterinary medicine are based on sales data (viz. amounts). Merle et al. , van RenAlthough TF is similar to amount-based calculations for antibiotic use, its comparison to other studies is restricted due to systematically different approaches in defining standard weights and DDDA. In addition, this comparison is hindered by varying group definitions. In the present VetCAb study, the observed animal holdings are divided into the groups piglet, weaner, fattening pig and sow. In other surveys, production type groups were summarized, such as those of Bos et al.  and JensOverall, internationally and even nationally, no harmonized approach exists for assessing antibiotic consumption; therefore, increased attention should be paid to standardizing definitions and calculation methods in antibiotic monitoring to compare antibiotic use.Despite the many differences described above, temporal trends within the systems can be compared. In this study, sufficient data were available to assess the temporal development of antibiotic usage in all animal groups. While the median TF for sows remained unchanged and constantly low over the study period, piglets and fattening pigs showed remarkably reduced antimicrobial consumption. In contrast, antibiotic use in weaners fluctuated significantly, which requires further investigation.In general, the marked differences in the TFs between groups may be explained by animals’ different exposures to infectious hazards. Since fattening animals  receive the most antibiotics in pig farming, this area should be the focus for reduction. The fluctuating TF medians in the weaner collective were striking, which could be explained by the possible misallocation described above.In total, a statistically significant reduction in antibiotic use over time is evident in this study. This is consistent with reported sales data in Germany, where since 2011, a reduction by 468 tons to approximately 1 238 tons was observed in 2014 . This trThe reduced antibiotic usage can also be seen in other European countries, as shown in Sjölund et al.’s study . The sixIn summary, nearly all countries with antibiotic use monitoring systems in livestock husbandry document success in reducing antibiotic consumption for many reasons. One of the main reasons is that awareness in both society and the agricultural sector has improved. This increase developed due to implementing monitoring systems, publishing scientific studies from across Europe e.g., , 45–50) –50 45–50International surveys show that antibiotic use in animal husbandry cannot be reduced indefinitely. In 2015, the National Veterinary Institute of Sweden (SVA) published the yearly Swedish Veterinary Antibiotic Resistance Monitoring (SVARM) results, which showed that the temporal trend of veterinary antimicrobial consumption in Sweden has reduced over several years. In contrast, antibiotic sales for pigs remained stagnate over the past five years. However, another change occurred instead. Product sales for individual medications increased, while sales of group medications decreased ; thus, iDiseases requiring antibiotic treatment can occur in any animal holding type. For this reason, the aim cannot be to ban antibiotic uses, but to change its application. Responsible antibiotic handling does not mean non-use, but prudent use. It must be assumed that in the future, a plateau will be reached, and the reduction will stagnate at the necessary level. Further studies are needed to assess the antimicrobial level needed to treat diseased animals without conflicting with animal welfare through the legal compulsion for further reductions.Furthermore, all measures must be evaluated regularly and in detail to adjust the monitoring and benchmarking system if necessary. As a first step, multiple linear regression for each defined production type group was performed to investigate weather monitoring antibiotic use should be accompanied by evaluating secondary data.In this study, the estimated means of TF rose with increasing farm size in all production type groups. In contrast, Vieira et al.  identifiIn our study, spatial factors did not significantly impact the TF, except for in weaners. This result is consistent with those of van Rennings et al. . AlthougThe factor "Farm category" has a significant effect on the TF in piglets, weaners and fattening pigs, while the sow model was unaffected. Fattening pigs show similar results to those of van der Fels-Klerx et al. ; on specAccording to van Rennings et al. , the infOverall, the factors, "Farm size", "Veterinarian" and "Farm category", appears to impact the TF, while the "Region" factor shows no effect when the data are adjusted for confounding. However, it has to be assumed that these three identified factors are not solely influential; thus, to improve existing systems for antibiotic monitoring or establish new intervention measures, additional studies are needed. Evaluating the secondary data may greatly benefit this.In the longitudinal VetCAb sentinel study, antibiotic administration decreased significantly over time in the study population. The factors, "Farm size", "Veterinarian" and "Farm category", appeared to impact the treatment frequency. Considering these effects, these factors should complement antibiotic use monitoring.S1 Fig(TIF)Click here for additional data file.S2 Fig(TIF)Click here for additional data file.S3 Fig(TIF)Click here for additional data file.S4 Fig(TIF)Click here for additional data file.S5 Fig(TIF)Click here for additional data file.S6 Fig(TIF)Click here for additional data file.S7 Fig(TIF)Click here for additional data file.S8 Fig(TIF)Click here for additional data file.S9 Fig(TIF)Click here for additional data file.S10 Fig(TIF)Click here for additional data file.S11 Fig(TIF)Click here for additional data file.S12 Fig(TIF)Click here for additional data file.S1 Table(DOCX)Click here for additional data file.S2 TableThe coloured lines show the estimated variances for observations within one veterinarian or within one of the six time-points.(DOCX)Click here for additional data file.


The rol17 (repressor of lrx1 17) mutant was identified as a new suppressor of lrx1 that induces also a short root phenotype. The ROL17 locus encodes isopropylmalate synthase 1, a protein involved in leucine biosynthesis. Dependent on growth conditions, mutations in ROL17 do not necessarily alter the level of leucine, but always cause development of the rol17 mutant phenotypes, suggesting that the mutation does not only influence leucine biosynthesis. Changes in the metabolome of rol17 mutants are also found in plants with inhibited TOR kinase activity. Furthermore, rol17 mutants show reduced sensitivity to the TOR kinase inhibitor AZD-8055, indicating a modified TOR network. Together, these data suggest that suppression of lrx1 by rol17 is the result of an alteration of the TOR network.The growth and development of organisms must be tightly controlled and adjusted to nutrient availability and metabolic activities. The Target of Rapamycin (TOR) network is a major control mechanism in eukaryotes and influences processes such as translation, mitochondrial activity, production of reactive oxygen species, and the cytoskeleton. In  TogetheLRX genes cause changes in cell wall composition and ultrastructure , an enzyme involved in leucine (Leu) biosynthesis. Metabolomic analysis revealed that the effect of rol17 does not correlate with reduced Leu accumulation, suggesting that IPMS1 might be involved in establishing a link between amino acid biosynthesis and the TOR network that is required to achieve coordinated plant growth and development.The observed suppression of Arabidopsis thaliana, ecotype Columbia (Col), was used for all experiments. The SAIL line rol17-2 is in the qrt1-2 mutant background  medium  or on Hoagland (HG) medium  and images were obtained with a DFC420 digital camera (Leica). For root length measurements, seedlings were grown as described above, the plates were scanned, and root length was measured using ImageJ software. On one plate, two genotypes were grown on a single lane, which was always at the same position on the plates (same distance from the top), to avoid positional effects that can influence plant growth. Several plate replicates were used to produce the data points.AZD-8055 was dissolved in DMSO and added to the MS medium (described above) after autoclaving. Sterilized seeds were directly plated, germinated, and grown on medium containing AZD-8055 for 7 days. For the control treatment without AZD-8055, only DMSO was added to the medium.rol17 and showing a wild type-like phenotype were isolated, and the phenotype was confirmed in the F3 generation. Fifty seedlings of each of the 10 F3 families were pooled, ground in liquid nitrogen, and DNA was extracted following an established protocol  and obtained for the lrx1 mutant and the lrx1 rol17 double mutant. Sequences of the lrx1 and lrx1 rol17 mutants were separately mapped to the Arabidopsis genome , and polymorphisms to the lrx1 sequence were subtracted from those to the lrx1 rol17 mutant. The resulting list of rol17-specific single nucleotide polymorphisms (SNPs) was filtered for mutations changing the sequence of encoded proteins based on the annotation provided by the TAIR database. For the SNP selection we used in-house Perl scripts (which can be provided upon request).For whole-genome sequencing, 10 seedlings of an F2 population segregating for IPMS1 and ACTIN2 . The RNA was quantified by using ND-1000 (Nanodrop) and 300 ng was used for reverse transcription using the iScript kit (Bio-Rad). The DNA produced was diluted 10-fold in nuclease-free water and 1 µl was used for PCR, using primers specific for –1 of the internal standard DL-2-aminoheptanedioic acid. The samples were briefly vortexed and centrifuged at 15 000 × g for 15 min. The collected supernatants were fully evaporated in a Savant SpeedVac concentrator (Thermo Fisher Scientific) at 42 °C, resuspended in 30 μl of 50% acetonitrile, and transferred to liquid chromatography (LC) vials. Leu quantification was performed using an ultra-performance LC (UPLC) system (Thermo Scientific Dionex UltiMate 3000) coupled to a Bruker Compact electrospray ionization quadrupole time-of-flight mass spectrometer . The UPLC separation was performed with a C18 reverse-phase column  at 45 °C using the following gradient of solvent A  and solvent B : 0–0.1 min, 99% A; 0.1–7 min, 30% A; 7.1–10 min, 99% A. The flow rate was 0.3 ml min–1 and 5 µl of each sample was injected. The electrospray ionization source was operated in positive mode and parameters were set as follows: gas temperature 220 °C, drying gas 9 l min–1, nebulizer 2.2 bar, capillary voltage 4500 V, and end plate offset 500 V. The instrument was set to acquire m/z 50–1300. All data were analyzed using DataAnalysis  and TargetAnalysis . Absolute Leu quantification was based on a standard curve between 0.06 and 1 µg. This analysis was performed using QuantAnalysis software .For comparison of Leu levels, entire seedlings grown for 8 days in a vertical orientation on either 0.5 × MS or HG medium containing phytagel (Sigma) and Ultrapure Agarose (Invitrogen), respectively, were collected. Per sample, 100 mg of fresh material was frozen in liquid nitrogen and ground with glass beads in a Retsch mill. Polar compounds were extracted with 70% methanol and 1 µg ml–1 (–1 methoxyamine (Sigma) containing 10 µg ml–1 of a C8 to C30 fatty acid methyl esters (FAMES) mixture was added and the samples were shaken for 90 minutes at 1400 rpm and 28 °C in an Eppendorf thermomixer. Next, 90 µl of N-methyl-N-trimethylsilyl-trifluoroacetamide (Aldrich) was added and the reaction continued for 30 min at 37 °C. After cooling, 50 µl was transferred to an Agilent vial for injection. Four hours after derivatization, 1 µl of sample was injected in splitless mode on an Agilent 7890A gas chromatograph coupled to an Agilent 5977B mass spectrometer. The column was an Rxi-5SilMS . The liner (Restek) was changed before each series analysis of 24 samples. The oven temperature was 70 °C for 7 min and then increased at 10 °C min–1 to 330 °C for 4 min (run length 36.5 min). Helium constant flow was 0.7 ml min–1. Temperatures were the following: injector 250 °C, transfer line 300 °C, source 230 °C, and quadrupole 150 °C. Samples and blanks were randomized. Three independently derivatized quality controls  were injected at the beginning, middle, and end of the analysis for monitoring the derivatization stability. An alkane mix  was injected in the middle of the queue for external retention index (RI) calibration and FAMES (C8 to C30) were added to each sample for internal RI calibration. Five scans per second were acquired. After the splitless analysis was performed, samples were injected in split mode (1:30) to avoid saturation of abundant compounds. Raw Agilent data files were converted to NetCDF format and analyzed with AMDIS (http://chemdata.nist.gov/mass-spc/amdis/). A home retention indices/mass spectra library built from the NIST (Agilent), Golm (P<0.01). Multivariate analysis  was then carried out on the selected metabolites. The concentrations of 77 metabolites were expressed in µg mg–1 fresh weight in the following way: ribitol  normalized peak area was calibrated to the response coefficient to ribitol of the standard of each of these 77 metabolites (one point in splitless mode and one point in split mode to ensure that the response was linear). This one-point calibration gives a good estimation of the absolute concentration.Seedlings were grown for 8 days in vertical orientation on HG medium supplemented with 1% glucose and 0.8% UltraPure Agarose (Invitrogen), and 100 mg of fresh tissue was collected, frozen in liquid nitrogen, and ground in a Retsch mill. A 50 mg sample of the ground powder was resuspended in 1 ml of –20 °C precooled water:acetonitrile:isopropanol  containing the internal standard ribitol at 4 µg mllrx1 mutant of Arabidopsis is characterized by a defect in root hair development but shows otherwise normal root growth because LRX1 is predominantly expressed in the root hairs  mutant seedlings that developed wild type-like root hairs—that is, a suppressed lrx1 phenotype—were selected, and their phenotype was confirmed in the M3 generation  of AZD-8055, while lrx1 rol17 seedlings were not affected at this concentration. Even at higher concentrations (0.5 μM), lrx1 rol17 seedlings showed less reduction in root length than lrx1 seedlings .Backcrossing of rol17 locus. To this end, in the segregating F2 population of a second backcross of lrx1 rol17 with lrx1, eight plants showing a rol17 phenotype were selected, the plant material was pooled, genomic DNA was extracted, and whole-genome sequencing was performed. In parallel, the original lrx1 mutant used for EMS mutagenesis , an α/β-hydrolase (α/β-HYD), isopropyl malate synthase 1 (IPMS1), and flavin-dependent monooxygenase 1 (FMO1)  , and werol17 see . lrx1 α/ rol17-1 , Fig. 2Aanalyzed . Homozygt growth , confirmt growth . By cont of lrx1 . This le rol17-2 . The rolc region . This Prg region  and has IPMS1 sequence 5′ of the T-DNA insertion, a band of comparable intensity was detected in the extracts of the wild type and lrx1 rol17-1, whereas lrx1 rol17-2 resulted in a weaker band; this observation suggested that the incomplete ipms1 mRNA in lrx1 rol17-2 is largely degraded, confirming previous findings  produced a strong band, confirming that RNA extraction and reverse transcription were successful in all samples.In a next step, total RNA was extracted from 7-day-old seedlings and semi-quantitative RT–PCR was performed to investigate transcript abundance in the two alleles . Using a rol17-1 . All samrol17 alleles in the LRX1 wild-type background, the lrx1 rol17-1 mutant was crossed with Col. In the F2 generation, plants with a short-root rol17 mutant phenotype homozygous for wild-type LRX1 were selected. Again, separation of either α/β-hyd or fmo1 from rol17-1 was not achieved, and rol17-1 thus contains also these two mutations  in the presence of the TOR inhibitor  in accumulation between the two lines, among which valine  was the only amino acid  that is produced from pyruvate in a series of enzymatic steps, most of which are shared with the synthesis of the BCAA Val  or comparable in the wild type and rol17 mutant lines (as in HG-grown seedlings), suggesting that the defect in plant growth cannot be simply explained by limited Leu availability. For the same reason, the function of Leu as a regulatory metabolite that mediates the regulation of gene expression , a group of sulfur- and nitrogen-containing secondary metabolites present in Brassicaceae, with over 40 different compounds in Arabidopsis (lrx1 root hair defect by the rol17 mutations (rol17 mutants reflects a modified TOR network that is likely to affect root hair cells as well. For the coordination of the diverse mechanisms leading to cell growth, plants must regulate cell-wall-modulating activities, since cell wall expansion is a rate-limiting step in turgor-driven cell growth (lrx1 is suppressed by modifying TOR signaling (lrx1 mutant phenotype (lrx1 (lrx1 mutant phenotype remains to be demonstrated. LRX-type proteins have recently been identified as extracellular receptors of RALF peptides (Suppression of the utations  can be el growth . Previouhenotype . The TORhenotype  and modiJXB onlineSupplementary data are available at Fig. S1. wakl4 does not suppress lrx1.Fig. S2. Root growth of T-DNA knockout lines of rol17 candidate genes.Fig. S3. IPMS1 protein comparison among different species.Table S1. Raw data of metabolomic analysis.Table S2. Primers used to identify the EMS polymorphisms.Table S3. Primers used to identify the T-DNA mutations alleles.Table S4. Primers used for RT–PCR.Supplementary Figures S1-S3Click here for additional data file.Supplementary Table S1Click here for additional data file.


Immunoglobulin (Ig) G4-related sclerosing disease is a pathological concept proposed in Japan during the early 2000s. This lesion-forming disease may exhibit characteristics of a systemic disease but often affects a single organ. To date, IgG4-related sclerosing disease in the mammary gland, or IgG4-related mastitis (IgG4-RM), has rarely been reported.Here, we describe the case of a female patient who was admitted to our hospital with the main complaints of left breast and axillary lymphadenopathy. A careful diagnostic imaging examination led to an initial suspicion of breast cancer. However, a needle biopsy led to a diagnosis of IgG4-RM. Subsequently, the patient was successfully treated with predonin.The treatment requirements for breast cancer and IgG4-RM differ considerably. This is a good example of a case wherein unnecessary surgical treatment, which is indicated for breast cancer, was avoided by needle biopsy. Accordingly, the patient was appropriately treated with steroids following a correct diagnosis. The concept of immunoglobulin (Ig) G4-related sclerosing disease was recently proposed in Japan to explain the similar pathological imaging findings and responses to steroid therapy between extra-pancreatic lesions associated with autoimmune pancreatitis and pancreatic pathologies associated with IgG4-positive plasma cell infiltration . Umbara Although IgG4-related sclerosing diseases occur in various organs, these lesions are rarely observed in the mammary glands , 7. In tA 70-year-old woman initially presented in the Department of Blood Medicine at our hospital with a complaint of reactive axillary lymphadenopathy 6 years earlier. Subsequently, a multiple nodule in the left breast was observed during a recent computed tomography follow-up, at which time the patient was introduced to our department. Her chief complaint involved mild left axillary pain. She had no notable personal or family history.During the physical examination, we palpated a soft, elastic, and egg-sized tumor with a smooth surface in the left breast upper region. This tumor exhibited mild tenderness. Additionally, we palpated multiple bean-sized tumors in the left axilla. The fusion status was unclear. Following mammography, the right and left mammary tissues were classified as categories 1 and 3, respectively, and the patient was diagnosed with asymmetric mammary gland tissue Fig. . ObviousGiven the examination findings, which differed from typical breast cancer, the differential diagnosis also included malignant lymphoma. Frequent bilateral cervical, supraclavicular fossa, axillary, and inguinal lymphadenopathies were observed. Many of these areas were thick, with a low cortical echo level and internal heterogeneity. Most of these abnormalities had lymph node gates, and no deviation of the lymph nodes was observed.A core needle biopsy of the left breast tissue revealed a high degree of mixed T and B lymphocytic and plasma cell infiltration, as well as interstitial fibrosis Fig. A. MammarAs noted, the concept of IgG4-related sclerosing disease was proposed to address the similarities of this condition with those of pathologic pancreatic extracorporeal lesions associated with autoimmune pancreatitis; additionally, both lesions respond well to steroid treatment , 8, 9. SThe existing comprehensive diagnostic criteria for IgG4-related sclerosing disease include the following items . ClinicaIn the present case, the mammary gland and axillary lymph node findings met the clinical criteria. The IgG4 level was not initially investigated because of the original suspicion of breast cancer; however, this parameter was later examined and found to be 882 mg/dL (reference range 4.5–117 mg/dL), which met the blood criterion. Furthermore, the analytical findings of the mammary gland tissue and lymph node met the pathological criteria. Accordingly, the present case was finally and definitively diagnosed with IgG4-RM.As noted, breast cancer was initially suspected, and IgG4-RM was diagnosed only after a needle biopsy. The diagnosis may have been reached sooner if an IgG4 analysis had been performed. However, this is not a realistic assumption. Still, in such cases, misdiagnosis can complicate treatment. Currently, surgery is the standard treatment for breast cancer, whereas IgG4-RM responds well to steroid therapy and does not tend to recur . TherefoIgG4-RM is very rare, and the clinical and imaging findings often lead to a suspicion of breast cancer. In such cases, a histopathological examination by a pathologist familiar with pathological conditions of the mammary gland is important to ensure a correct diagnosis and the avoidance of unnecessary surgical procedures.


The probability of steel corrosion in the fly ash concrete was assessed by measuring the half-cell potentials of steel bars within beams dimensions of 100 × 100 × 500 mm3, and the flexural strengths of these beams after 300 days of immersion in a 5% NaCl solution were determined. The results demonstrate that the compressive strength of fly ash concrete is reduced at an early age but increases as the concrete continues to hydrate. The fly ash increases the sulfuric acid resistance of concrete. Fly ash additions have only a limited effect on reducing the risk of probability of corrosion of steel in the concrete. The load capacities of 10% and 20% fly ash reinforced concrete beams are higher than that of the control beams after 300 days immersed in a 5% NaCl solution.Vietnamese fly ash was used as a partial replacement for ordinary Portland cement in the proportions of 10%, 20% and 40%, while the water to cementitious ratios were kept constant at 0.42, 0.5 and 0.55, respectively, for three groups. The compressive strengths of all mixes were determined up to 90 days. The acid resistance of fly ash concrete was examined by the mass loss and compressive strength loss of 100 × 100 × 100 mm The widespread use of concrete as a construction material has many associated environmental impacts related to its raw materials and manufacturing, most notably the production of Portland cement. By comparison, fly ash is a by-product of coal-fired electricity generation, but has the potential to be used as a supplementary cementitious material in concrete, replacing a proportion of the Portland cement ,2.42−) are generally higher in the Class C fly ash than in the Class F fly ash [2O and K2O), carbon  and sulfate (SO3) can also affect the performance of the fly ash.Fly ash (FA) is classified by several different standards. Based on the source of origin and composition, ASTM C618, standard specification for coal fly ash and raw or calcined natural pozzolan for use in concrete  divides  fly ash  divides 3 of fly ash as a partial cement replacement of concrete with an estimated saving of 3,000 tonnes of ordinary Portland cement (OPC) [The use of fly ash as a supplementary cementitious material (SCM) in concrete potentially has economic and performance advantages, including improved workability, enhanced mix efficiency and increased durability. Fly ash as a cement replacement is also widely recognised and specified in standards covering SCMs  and genent (OPC) .3S (3CaO SiO2), dicalcium silicate, C2S (2CaO SiO2), tricalcium aluminate, C3A (3CaO Al2O3) and tetra-calcium alumino-ferrite, C4AF (4CaO Al2O3 Fe2O3). These compounds react with water to produce a hydrated calcium silicate (CSH) and lime. However, if fly ash is added to the mix, it reacts with the lime to form additional CSH, contributing to the cementing product produced by the normal hydration of the cement paste [Fly ash can directly contribute to sustainable development by reducing the quantity of Portland cement required while maintaining other criteria including engineering design aspects, constructional aspects and economic advantages . This isnt paste .There has been significant research concerning the influence of different fly ashes on the physical properties and durability of concrete. The incorporation of fly ash into the mixture greatly influences the properties of the fresh concrete plus the mechanical properties and durability of the hardened concrete. The extent to which fly ash affects these properties is dependent not only on the level and composition of the fly ash, but also on other parameters including the composition and proportions of the other ingredients in the concrete mix, the type and size of the concrete component, the exposure conditions during and after placement and the optimum construction practices. Clearly, there is no single replacement level that is best suited for all applications . The strThis paper investigates the development of compressive strength, acid resistance via visual monitoring of the concrete surfaces, mass loss and compressive strength loss; and the reduced probability of corrosion for embedded steel for concrete made with OPC partially replaced by fly ash from Northern Vietnam in varying proportions of 0%, 10%, 20% and 40%, and varying water to cementitious material (W–CM) ratios of 0.42, 0.50 and 0.55.The cementitious materials used in this study consisted of ordinary Portland cement from the Song Gianh Company, Quang Binh, Vietnam and ASTM Class F fly ash  from PhaThe compositions of all mixes are presented in 3 were cast for each mix to determine the compressive strengths at 1, 7, 14, 28, 56 and 90 days. All specimens were demolded after one day and cured in water at approximately 27 °C until the test dates.The compressive strength tests were conducted in accordance with BS EN 12390-3:2009: testing hardened concrete—part 3: compressive strength of test specimens . Eightee3 were cast from which three cubes were used to determine the mass loss and residual compressive strength after immersion in a 10% sulfuric acid (H2SO4) solution for 90 days in the laboratory. The 10% sulfuric acid solution was made by dilution directly from 98% concentrated sulfuric acid with potable water. It is noted that 10% sulfuric acid does not represent a specific exposure environment; however, this concentration of acid has been used to test the sulfuric acid resistance of construction products by the Los Angeles County for over 20 years [The acid resistance of the concrete mixes was evaluated in accordance with the modified ASTM C267 standard test methods for chemical resistance of mortars, grouts, and monolithic surfacings and polymer concretes . Six cub20 years . The rel2 and a length of 500 mm with one 8 mm diameter steel bar of grade 250, with a yield strength of 250 MPa, located towards the lower face of the beams with a reinforcement cover of 15 mm  was almost equal to the compressive strength of control specimens M1  at 56 days a. The coAfter 90 days of immersion in a 10% sulfuric acid solution, the surfaces of all concrete cubes were cleaned and appear as shown in Counter-intuitively, as the water to cementitious ratio increased the resistance to 10%, the sulfuric acid solution by the fly ash containing specimens also increased. For example, comparison of the M4  and M8  specimens see  show theThe change in mass and compressive strength for specimens exposed to 10% sulfuric acid solution are shown in Similar to surface degradation of the concrete, the mass loss reduced when W–CM ratios increased. For example, at a 0% fly ash replacement, the mass losses of the concrete specimens are 11.4%, 9.3% and 6.1% for W–CM ratios of 0.42, 0.5 and 0.55, respectively. At a 10% fly ash replacement, the mass losses of the concrete specimens are 6%, 6.7% and 4.4% for W–CM ratios of 0.42, 0.5 and 0.55, respectively. At a 20% fly ash replacement, the mass losses of the concrete specimens are 6.9%, 6.6% and 1.3 % for W–CM ratios of 0.42, 0.5 and 0.55, respectively. At a 40% fly ash replacement, the mass losses of the concrete specimens are 1.5%, 0.4% and 0.4 % for W–CM ratios of 0.42, 0.5 and 0.55, respectively. It can be concluded that fly ash reduces the mass loss from the concrete surface resulting from sulfuric acid exposure, and the higher the proportion of fly ash replacements, the lower the mass loss from the concrete surface. Moreover, the mass loss also depends on the water to cementitious ratio, with higher W–CM ratios resulting in lower mass loss.As previously observed with respect to surface degradation and mass loss, at a 0% and 10% fly ash replacement, the compressive strength loss reduced when W–CM ratios increased. For example, the compressive strengths loss of concrete with a 0% fly ash replacement are 61.2%, 50.1% and 48.5% for W–CM ratios of 0.42, 0.5 and 0.55, respectively. The compressive strengths losses of concrete at a 10% fly ash replacement are 53.9%, 36.9% and 17.4% for W–CM ratios of 0.42, 0.5 and 0.55 respectively. At 20% and 40% fly ash replacement, the compressive strengths losses of concrete for W–CM = 0.5 are higher than that for W–CM of 0.42 and 0.55. In general, fly ash decreases the compressive strength loss resulting from sulfuric acid exposure demonstrating an increased acid resistance. The greater the level of fly ash replacement, the lower the loss in compressive strength. Within the scope of this investigation, a W–CM ratio of 0.55 demonstrates the highest acid resistance, compared to W–CMs of 0.42 and 0.5.Half-cell potentials of the embedded steel bar specimens of Groups 1, 2 and 3 are plotted in The half-cell potentials of all the steel bars were more negative than −250 mV after 21 days of immersion in a 5% NaCl solution, consistent with a high probability of corrosion activity. Within the scope of this investigation fly ash showed little beneficial effect on the initial corrosion resistance of steel bars in concrete, with the 10% fly ash replacement appearing to have the most positive effect.After 301 days of immersion in 5% NaCl solution, all beams were tested in flexure under three point bending. The yield and ultimate loads of all beams were determined, and the results are presented in Although earlier results indicate that the compressive strengths of concrete made with partial fly ash replacement can match that of control concrete without fly ash after 90 days , the loaFor Group 2 (W–CM = 0.5), the yield load of the control beam remained higher than that of the fly ash beams. The yield load of the control beam was 16.00 kN, while the yield load of the 10%, 20% and 40% fly ash replacement beams were 17.00, 16.2 and 15.8 kN, respectively. However, the ultimate load of the 10% and 20% fly ash replacement beams were higher than that of the control beam while the ultimate load of the 40% fly ash beam was smaller than that of the control beam (0% fly ash). The ultimate failure load of the control beam was 17.32 kN, while the ultimate failure loads for 10%, 20% and 40% fly ash replacement beams were 18.45, 17.97 and 16.95 kN, respectively. This trend is consistent with that previously observed for the development of compressive strength of fly ash concrete in For Group 3 (W–CM = 0.55) the yield load and ultimate load of the fly ash replacement beams were higher than that of the control beam. The yield load of the control beam was 14 kN, while the yield load of the 10%, 20% and 40% fly ash replacement beams were 18, 14.5 and 15.5 kN, respectively. The ultimate failure load of the control beam was 16.71 kN, while the ultimate failure loads for the 10%, 20% and 40% fly ash replacement beams were 19.02, 17.66 and 18.73 kN, respectively. It can be seen that the load capacity of the Group 3 beams are consistent with the trend in compressive strength development .The Vietnamese sourced fly ash investigated in this study contributes to improvements in the workability of fresh concrete. This is consistent with differences between the spherical shape of fly ash particles and angular shape of the cement particles, as confirmed by previous research.Within the range of investigation (10% to 40% replacement), fly ash reduced the compressive strength of the concrete at early age, either before 28 days or 56 days depending on the W–CM ratios. After this time, the compressive strength of the fly ash specimens continues to develop, albeit slowly, and gains higher strengths than that of the control specimens, while the compressive strengths of the control specimens (0% fly ash) is no longer developed.Within the range of investigation, (10% to 40% replacement), the optimum fly ash replacement proportion was found to be 20% by weight of Portland cement.Fly ash increases the sulfuric acid resistance of the concrete. This results in a reduction in surface degradation, mass loss and compressive strength loss resulting from exposure to sulfuric acid solution. The greater the level of fly ash replacement, the less surface degradation, mass loss and compressive strength loss was observed. Within the scope of this investigation, water to cementitious ratio of 0.55 shows the highest acid resistance compared with values of 0.42 and 0.5.Within the scope of this investigation, fly ash has had little effect on reducing the probability of corrosion of steel bars embedded in concrete specimens, but a 10% fly ash replacement showed greatest benefit.In general, 10% and 20% fly ash reinforced concrete beams show better flexural resistance than that of the control beams without fly ash after 300 days exposure in a 5% NaCl solution.Further research should be conducted at different levels of replacements  to identify optimum replacement levels for the enhancement of the various performance criteria investigated.Based on the results reported in this paper, the following conclusions can be made:


The environment receives antibiotics through a combination of direct application , as well as indirect release through pharmaceutical manufacturing, sewage and animal manure. Antibiotic concentrations in many sewage-impacted rivers are thought to be sufficient to select for antibiotic resistance genes. Yet, because antibiotics are nearly always found associated with antibiotic-resistant faecal bacteria in wastewater, it is difficult to distinguish the selective role of effluent antibiotics within a ‘sea’ of gut-derived resistance genes. Here we examine the potential for macrolide and fluoroquinolone prescribing in England to select for resistance in the River Thames catchment, England. We show that 64% and 74% of the length of the modelled catchment is chronically exposed to putative resistance-selecting concentrations (PNEC) of macrolides and fluoroquinolones, respectively. Under current macrolide usage, 115 km of the modelled River Thames catchment  exceeds the PNEC by 5-fold. Similarly, under current fluoroquinolone usage, 223 km of the modelled River Thames catchment  exceeds the PNEC by 5-fold. Our results reveal that if reduced prescribing was the sole mitigating measure, that macrolide and fluoroquinolone prescribing would need to decline by 77% and 85%, respectively, to limit resistance selection in the catchment. Significant reductions in antibiotic prescribing are feasible, but innovation in sewage-treatment will be necessary for achieving substantially-reduced antibiotic loads and inactivation of DNA-pollution from resistant bacteria. Greater confidence is needed in current risk-based targets for antibiotics, particularly in mixtures, to better inform environmental risk assessments and mitigation. The environment receives antibiotics through a combination of direct application , as well as indirect release through pharmaceutical manufacturing, sewage and animal manure ,2. As paThe QPP in 2015/16 aimed to reduce antibiotic over-use and inappropriate prescribing through a reduction in:the number of antibiotics prescribed in primary care by ≥1% from each Clinical Commissioning Group (CCG’s) 2013/14 value;the proportion of broad-spectrum antibiotics prescribed in primary care. Specifically, the QPP aims to reduce prescriptions of co-amoxiclav, cephalosporins and fluoroquinolones by 10%  as a percentage of the total number of antibiotics prescribed in primary care, or to be below the 2013/14 median proportion for English CCGs (11.3%), whichever represents the smallest reduction.The NHS of England successfully reduced their antibiotic prescriptions in 2015/16 by 7.3% (37.03 million items to 34.34 million) as compared to 2014/15. The NHS also saw a reduction of 16% in broad-spectrum antibiotics (3.94 million items to 3.3 million). The goal for 2016/17 was, in part, to reduce total antibiotic prescribing in primary care by 4% (based on 2013/14) and broad-spectrum antibiotics by 20% (based on 2014/15). The majority of the reductions seen in 2016/17 were for amoxicillin, co-amoxiclav, and some cephalosporins, not macrolides or fluoroquinolones. The only exceptions being erythromycin, which saw a reduction in consumption in the primary care setting, of 0.078 DDDs and azithromycin which saw an increase of 0.023 DDDs per 1000 inhabitants per day in England [Any reduction in antibiotic prescribing would result in a proportional reduction in antibiotics released into wastewater. This is because a significant fraction of antibiotics are conserved as they pass through the body before being excreted as a mixture of the parent compound and metabolites in the urine and faeces ,11. The This study focused on two questions that explore the link between antibiotic use and environmental impact:To what extent might current macrolide and fluoroquinolone prescribing contribute to antibiotic resistance selection in sewage-impacted rivers in southern England?How much of a reduction in macrolide and fluoroquinolone prescribing might be required to alleviate the hazard of antibiotic resistance selection in rivers, if it was the sole means of mitigating environmental load?in vivo and the environment, and as such, are found in nearly all antibiotic surveillance studies [The study focused on macrolides and fluoroquinolones because: 1) they are two of the more persistent classes of antibiotics  studies –31; 2) t studies ; and, 3) studies ,34.th quartile of predicted values of annual dilution factors, i.e., between 2.24 and 6.26 [The River Thames catchment  in southern England was selected for this study as it is the most highly populous catchment in the United Kingdom (nearly 4 million people). It also might be seen as a realistic worst-case scenario, as this part of England is in the 25and 6.26 . Many riand 6.26 ,36–38.Macrolide prescribing data for each month of 2015/16 were acquired from the NHS Business Service Authority (NHSBSA), i.e., azithromycin, clarithromycin and erythromycin . FluoroqNHS prescription data for each CCG per month in 2014/15 were converted to units of kg , and thein vivo, which is a function of health, age, gender, ethnicity, as well as dosage and mode of administration, e.g., capsule, injection. Given the large uncertainty associated with estimating excretion rates across diverse populations, an average rate acquired from the literature was used: macrolide excretion rate of 32.2% and 64.2% for fluoroquinolones  Suiteescribed . Estimatescribed –51, withLow Flows 2000 Water Quality eXtension (LF2000-WQX) model ,53 is anIn summary, LF2000-WQX was parameterised with the highest monthly fluoroquinolone and macrolide prescription rate for each of the four CCGs  . Lowest Modelled PNECs were acquired from Bengtsson-Palme and Larsson (2016) owing to the absence of empirically-determined MSCs for most of the study antibiotics. The PNECs derived in Bengtsson-Palme and Larsson (2016) were selected to inform antibiotic discharge limits from pharmaceutical manufacturing by the AMR Industry Alliance . The PNEPNECs for fluoroquinolones ranged from 0.064 to 0.5 μg/L and for macrolides 0.25 to 1 μg/L . When prThis study aimed to understand the degree of resistance selection that might be occurring in the River Thames catchment under current macrolide and fluoroquinolone prescribing practice by the NHS as well as after foreseeable and aspirational reductions in prescribing. The objective was to estimate the level of reduction in NHS antibiotic prescribing that might be necessary to reduce the hazard of resistance selection in sewage-impacted rivers.The maxima PECs for macrolides and fluoroquinolones prescribed in 2015/16 were 4.3 μg/L and 2.0 μg/L, respectively. Hazard characterisation revealed 279 out of 457 reaches in the catchment are ‘at risk’ or ‘critical’ for macrolide resistance selection —equatingConsistent with the 2015/16 QPP goals, a 4% reduction in macrolide prescribing saw a 3.8% reduction in the length of the modelled Thames catchment ‘at risk’ for macrolide resistance selection , and a 0.1% reduction in the length of the modelled Thames catchment ‘at risk’ for fluoroquinolone resistance selection .A more ambitious 20% reduction of the 2015/16 prescription rate of macrolides resulted in an 8.9% reduction in the length of the modelled Thames catchment ‘at risk’ for macrolide resistance selection . A 20% reduction in fluoroquinolones resulted in a 5.4% reduction in the length of the modelled Thames catchment ‘at risk’ for fluoroquinolone resistance selection .A sensitivity analysis was conducted to identify the NHS prescribing rate that protects ≥90% of the length of the modelled Thames catchment from macrolide and fluoroquinolone resistance selection. A target of 90% was a pragmatic decision, as many rivers in England are highly impacted by, or solely composed of, sewage effluent—particularly in headwaters. Hence, a target of 100% would be unrealistic and necessitate even more dramatic reductions in antibiotic use or zero effluent discharge.The sensitivity analysis revealed that macrolide prescriptions must decline by 77% to protect 90.4% of the length of the Thames catchment from macrolide resistance selection ; Fig 4A.The goal of this study was to evaluate how antibiotic prescribing, alone, contributes to antibiotic resistance selection in the aquatic environment. Such a perspective is fundamentally naïve as the catchment contains considerable land for grazing and is at risk of receiving animal waste containing antibiotics. Pollutants found in sewage, agriculture, and street runoff can co-select for antibiotic resistance, making this model a conservative estimate of the hazard of resistance selection –68.in vivo, perhaps during antibiotic treatment of human infections [in situ [CTX-M-14 [CTX-M-14, in particular, has been attributed to conjugative plasmids rather than to clonal expansion of a bacterial host strain owing to the high level of clonal diversity [A non-trivial proportion of the resistance genes found downstream of STPs originate from human gut bacteria, many of which have acquired resistance fections –71. Antifections ,73 maintfections –76; 2) hfections ; 3) sele[in situ ,78,79 an[in situ . In envi[in situ . Once ev[in situ  and blaCCTX-M-14 . Dissemiiversity –85. Conviversity ,87.et al. 2011, isolated extended-spectrum β-lactamase-producing Escherichia coli (blaCTX-M-14) belonging to the clinically important O25b:H4-ST131 lineage from the River Thames in west London [et al. 2015, analysed sediment samples from thirteen sites across the River Thames basin for class 1 integron prevalence and cefotaxime- -resistant E. coli [et al. 2016, showed a rapid increase in class 1 integrons (intI1) in natural river biofilms, within the Thames catchment, exposed to trace levels of additional STP effluent [intI1 reported within sewage-effluent-exposed periphyton occurred without statistically significant changes in the microbial community. This result was suggestive of increased horizontal gene transfer—a phenomenon that is important for the dissemination of antibiotic resistance genes. Using a novel Raman-Deuterium Isotope Probing technique, Song et al. 2017 reported 35±5%, 28±3%, 25±1% of the total bacterial population recovered from the River Thames with resistance to carbenicillin-, kanamycin- and both antibiotics, respectively [2O) and minimally-destructive instrument for resistance detection (Raman) thereby minimises the culture bias usually introduced into such determinations, potentially offering a more realistic measure of the prevalence of antibiotic resistance within the microbiota of the River Thames.Evidence of antibiotic-resistant microorganisms recovered from the River Thames catchment has been reported in the literature. Djanji t London . Amos et E. coli . The auteffluent . The staectively . The useTo our knowledge, this study is the first attempt to model the impact of current and aspirational antibiotic prescribing in England on antibiotic resistance selection in freshwater rivers. The study’s approach reflects the state of our knowledge at this time, and as such, is limited in many ways.The results do not reflect the granular differences in prescribing that are seen between small CCGs as there would be no way to attribute an antibiotic user to a particular STP confidently. It is expected that if such an effort were possible, it would highlight elevated antibiotics in STPs that have: older demographics , hospitIn this model, we applied any reductions in antibiotic prescribing, i.e., 4 or 20%, uniformly across all antibiotics within the class. However, the use of antibiotics within a class are unlikely to be uniformly reduced. As a result, some reductions in prescribing could delay or hasten the time to achieve ‘low risk’. For example, ciprofloxacin is the most ‘potent’ fluoroquinolone in its class, with a PNEC of 64 ng/L; ofloxacin and norfloxacin are less ‘potent’, with a PNEC of 500 ng/L. In other words, ciprofloxacin is 7.8 times more potent than ofloxacin and norfloxacin. Hence, the benefit gained from reducing 1 unit of ciprofloxacin necessitates a reduction in 7.8 units of ofloxacin or norfloxacin. As ciprofloxacin represents the majority of fluoroquinolone prescribed 96.9%; , any redSimilarly, macrolides azithromycin and clarithromycin have PNECs of 250 ng/L, four times more potent than erythromycin (1000 ng/L). Prescription of macrolides varies considerably between the four study CCGs Tables , with clThe PNECs employed in this study have recently emerged as modelled estimates for assessing the hazard of resistance selection . To dateet al. 2018, reported that synergistic and antagonistic interactions increased in frequency with the number of drugs in the bacteria’s environment [Recent experimental evidence suggests antibiotics can act synergistically and antagonistically when in mixtures ,97. Tekiet al. 2018, demonstrated that many synergies were found within the same class of antibiotic, in particular, where the same cellular process was targeted. The authors postulated that by targeting the same functional process at different steps, drug combinations of the same class could bypass the apparent redundancy of having multiple antibiotics within the same class and exhibit a synergistic effect [Brochado c effect . The autc effect . NotablyAnother limitation of this study is that it does not take into account the presence of many potentially relevant chemicals that are known to be present in sewage and sewage-impacted rivers, such as:antibiotics from agriculture and animal use ;biocides, which have been shown to co-select for antibiotic resistance genes –101;metals, which have been shown to co-select for antibiotic resistance genes –105;other classes of pharmaceuticals that might have synergistic or antagonistic impacts on resistance selection ,106,107 herbicides and pesticides that have been shown to co-select for resistance genes ,109.It is impractical to experimentally test all the chemicals found in sewage in isolation and mixtures for the threshold concentration that allows for resistance selection, as there are simply too many. However, our environment can be assayed for such insight, by measuring the diversity and quantity of antibiotic resistance genes in the river environment and their relationship to STPs, farms, hospitals, aquaculture, urban runoff, etc. Where ‘pristine’ environments still exist, they might serve as benchmarks for qualifying and quantifying ‘natural’ resistance gene prevalence and their biogeography. However, this might prove difficult as wildlife have been implicated in the dissemination of human clinical resistance genes, making ‘pristine’ locations potentially unattainable . Quantif3/d. A majority of the small STPs not included in the model are located in the upper-most reaches of the catchment where flows are typically very low. Headwaters impacted by small STPs are likely to have a disproportionate impact on seeding the catchment with pharmaceuticals as well as antibiotic-resistant bacteria, the former of which would further add to the total load of macrolides and fluoroquinolones in the catchment. The omission of these STPs is unlikely to increase the antibiotic load in the catchment substantially; however, it might impact the DNA ‘seeding’ and maintenance of antibiotic resistance.LF2000-WQX generates PECs from STPs characterised by dry weather flows of >5000 mIn this study, we projected a decline in antibiotic prescribing without considering the likely change in other important factors that would occur concurrently with a gradual reduction in prescribing. An increasing and ageing UK population will consume more pharmaceuticals per capita, increasing the antibiotic load. Dryer summers, resulting from climate change, might impact the frequency PNECs are exceeded owing to lower dilution ,111. MorPrevious research using LF2000-WQX to generate PECs, e.g., steroid estrogens ,112, gluhttps://ecdc.europa.eu/en/antimicrobial-consumption/database/country-overview). Macrolide prescribing in the Netherlands (1.38 DDD/1000/d) was only 47% that of the UK (2.90 DDD/1000/d). The extent to which the Netherlands still overprescribes and misprescribes macrolides would be highly instructive in defining safe limits for further reductions in macrolide prescribing. Notably, the UK has a lower fluoroquinolone prescribing rate in the community (0.44 DDD/1000/d) as compared to the Netherlands (0.75). Hence, there are important lessons to be mutually shared across Europe and more widely on how to optimise antibiotic prescribing—a point not lost on the Advisory Committee on Antimicrobial Prescribing, Resistance and Healthcare Associated Infection [Reduction of antibiotics in the environment can be achieved through a range of mitigating actions, the first of which can be through improved antibiotic stewardship. The results of this study indicate that current goals for antibiotic stewardship do not go far enough ,115. In nfection  and Publnfection .The UK has reported between 8.8% and 23.1% of all systemic antibiotic prescriptions in English primary care as inappropriate, with some high prescribing practices in England capable of reducing antibiotic prescriptions by as much as 52.9% . In a liA step-change in the way we currently handle our wastewater in needed to tackle the challenge of antibiotic and DNA pollution. One option is to set emission limits on the concentration of antibiotics, in much the same way the pharmaceutical industry has voluntarily adopted for its manufacturing supply chain . The setMoreover, there is a rapidly growing list of chemicals that are found within sewage effluent that has been shown to select or co-select for ARGs, i.e., antiepileptics , biocideIt is relevant to highlight that any engineering solutions employed for the removal of antibiotics from sewage effluent might be ineffective in reducing the DNA pollution from antibiotic-resistant bacteria. Co-development of engineering solutions to tackle the chemical and biological drivers of ARGs in the environment is required to reduce the environmental pressure caused by our wastewater. In addition, the by-products of STP, sludge, which contains antibiotic resistance, antibiotics and non-antibiotic chemical drivers of resistance are currently amended to land, representing additional risks to humans and the environment , but areshould be met through changes in prescribing. Arguably, environmental targets could be more readily achieved by a holistic, integrated AMR action plan, which constrains and optimises antibiotic prescribing, while also addressing the chronic release of antimicrobials, biocides, metals and resistance genes from STP effluent.This study explores the reduction in macrolide and fluoroquinolone prescribing needed to alleviate the modelled hazard from antibiotic resistance selection in sewage-impacted rivers. It is unclear if the projected reductions in antibiotic prescriptions of 77 to 85% could be achieved solely through reduced prescribing by the NHS. Moreover, it remains unexplored whether, ethically, it