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• K s was measured before and after sowing along a slope transect in Northeast China. • Sowing decreased K s and its spatial variability overall across the transect. • Sowing shifted K s structure from moderately-structured exponential to pure nugget. • K s distribution was dominated by BD, CLAY and SR both before and after sowing. Saturated hydraulic conductivity (K s) and its spatial variability are essential for the simulation of water and solute transport in the vadose zone. Mechanical operations have been increasingly employed in agricultural systems during recent decades to improve crop establishment, but their impact on K s spatial variability has rarely been evaluated. The objectives were to characterize the slope-scale variability of K s and to identify the primary controls dominating K s distributions before and after mechanical sowing. Along a 900 m slope transect in the black soil region of Northeast China, soil samples were collected in an interval of 20 m, and K s, bulk density (BD), particle-size distribution, wet-aggregate stability (WAS), soil organic carbon content (SOC) and land surface roughness (SR) were investigated before and after mechanical sowing in the spring. The results show that sowing significantly decreased K s along the transect (p < 0.01). Partly due to the strong comparisons among three different sections with respect to soil erosion, i.e., original, erosive and deposited sections, large K s spatial variability was detected both before and after sowing. According to the semivariogram analysis, nevertheless, sowing decreased the semivariances of K s overall and altered its spatial structure, i.e., from an exponential semivariogram possessing a sill of 0.72 mm2 min−2 and exhibiting a moderate spatial dependency before sowing to a pure nugget effect value of 0.27 mm2 min−2 corresponding to random distribution after sowing. Using the state-space approach, BD, CLAY and SR were identified as the main factors regulating K s spatial distributions, whether before or after sowing. These findings demonstrate the remarkable impact of mechanical sowing on K s and its spatial variability, and hold important implications for hydrological modeling and agricultural management in the black soil region of Northeast China. [ABSTRACT FROM AUTHOR]

Salmonella are major pathogens that cause foodborne diseases. In this work, a broad-spectrum Salmonella nanobody-01 (Nb-01) was isolated and applied in the development of a streptavidin-bridged sandwich ELISA (SAB-ELISA) for simultaneously identifying five Salmonella serovars, including Salmonella Enteritidis (S. Enteritidis), Salmonella Typhimurium (S. Typhimurium), Salmonella London (S. London), Salmonella Paratyphi B (S. Paratyphi B) and Salmonella Hadar (S. Hadar). In this work, streptavidin (SA) was utilized as a scaffold to directionally immobilize biotinylated nanobody (BiNb) and Salmonella was detected by phage-displayed nanobodies. The SAB-ELISA can be accomplished within 180 min with a limit of detection (LOD) of 6.31 × 103 colony forming units (CFU) mL−1, 9.15 × 103 CFU mL−1, 4.23 × 103 CFU mL−1, 7.31 × 103 CFU mL−1 and 7.25 × 103 CFU mL−1 towards S. Typhimurium, S. Enteritidis, S. London, S. Paratyphi B and S. Hadar, respectively. In comparison of sandwich ELISA by passive immobilization of Nb-01 on polystyrene plate, the sensitivity was increased by around 6-fold, which confirmed the enhanced immobilization efficacy of SAB-ELISA. Furthermore, the feasibility of the assay for S. Typhimurium determination in actual samples was evaluated, showing excellent recovery, inter-day and intra-day precision. [Display omitted] • One broad-spectrum Salmonella nanobody and four S. typhimurium -specific nanobodies were obtained for the first time. • A novel nanobody-based ELISA was developed for monitoring five Salmonella species. • The streptavidin-bridged enhanced sandwich ELISA exhibited superior analytical performance for Salmonella determination. [ABSTRACT FROM AUTHOR]

• There are antigenic cross-reaction among human, swine, rabbit and avian HEV capsid proteins. • Common epitopes of human, swine and rabbit HEVs are immunodominant epitopes for all the three HEVs. • Common epitopes of human, swine, rabbit and avian HEVs are only immunodominant for avian HEV. Hepatitis E virus (HEV), a zoonotic virus, infects many animal species, including humans. Capsid proteins of human, swine, rabbit and avian HEVs share 48 %–100 % amino acid identity. In the present study, antigenic cross-reactivity among human, swine, rabbit and avian HEV capsid proteins were analyzed in detail using indirect and blocking enzyme-linked immunosorbent assays (ELISAs). The C-terminal 268 amino acids of genotype 1 human, genotype 4 swine, genotype 3 rabbit and genotype B3 avian HEV capsid proteins served as coating antigens for ELISA. Hyperimmune rabbit antisera (against four HEV capsid proteins) and human, pig, rabbit and chicken clinical sera were as primary antibodies. Closely correlated and statistically indistinguishable results were obtained for detection of anti-HEV antibodies in human and pig sera using human, swine and rabbit HEV capsid proteins as coating antigens. Moderately correlated differences in detection of anti-HEV antibodies in rabbit sera were obtained using the three capsid proteins. Statistically significant differences with no correlations were obtained for anti-HEV antibodies detection in chicken sera between avian HEV capsid protein and human, swine and rabbit ones. Blocking ELISA results demonstrated that two common epitopes among the four species HEVs were immunodominant in avian HEV, but were non-immunodominant in human, swine and rabbit HEVs. Nevertheless, three epitopes common to human, swine and rabbit HEVs were all immunodominant epitopes for the three species HEVs. Collectively, these results demonstrate that anti-HEV antibodies in human and pig sera can be detected using human, swine and rabbit HEV capsid proteins. By contrast, for optimal detection of anti-HEV antibodies in rabbit and chicken sera, the respective rabbit and avian HEV capsid proteins should be used. These results provide insights to guide future development of serological assays for diagnosing HEV infections in various animal species. [ABSTRACT FROM AUTHOR]

Structure from motion (SfM) photogrammetry is a cost-effective topographic survey tool capable of producing high-quality 3-dimensional structure of a landform. Yet its application has rarely been reported in rill and interrill erosion at the relatively small spatial scales, especially when taking place in the loess that is vulnerable to erosion. The objective was to examine the accuracy and limits of SfM in quantifying rill and interrill erosion occurring in a typical loess during consecutive rainfall simulations. The loess collected from the plough layer of a cropland in the Loess Plateau of China was packed into a 200 × 100 × 35 cm runoff plot and received simulated rainfall at the intensity of 90 mm h−1 on three slopes of 10°, 15° and 20°. A portable laser scanner (LS) and SfM were used to measure soil surface at every 30 min until rill emergence and after another 30-min rainfall aiming to study rill development. Meanwhile, runoff and sediment samples were collected at the plot outlet and oven-dried to calculate the soil loss. The results showed that the elevation differences calculated by subtracting digital elevation models (DEMs) derived by SfM and LS mainly fell between −2 and 2 mm. Moreover, the root mean square error (RMSE) and mean absolute error (MAE) were mostly smaller than 3 mm, suggesting accurate soil erosion measurement made by SfM at the plot scale. Considering the surface variations, the relative RMSE and MAE, i.e., dividing over the mean elevations measured by LS, were found to decrease as soil erosion proceeded and rills emerged. The rill morphology comparison, however, suggested a better fit of SfM for rills larger than 9 cm in maximum surface width, 6.0 × 10−2 m2 in area and 0.9 × 10−3 m3 in volume. In accordance with DEM comparisons, the soil losses estimated by SfM and LS were statistically similar. Nevertheless, these values were much greater than the amount of sediments collected for the early simulation runs, which might be explained primarily by the settling of loess when subject to heavy rainfall. But as rainfall continued and rills further developed, the misestimations made by LS and SfM remarkably dropped, i.e., from −17.8% to 4.9% and from −18.1% to 4.3%, respectively. These findings suggest a generally higher accuracy of SfM in quantifying rill erosion with more fluctuating soil surface than in interrill erosion measurement. • SfM was evaluated for rill and interrill erosion measurements using rainfall simulations. • DEMs and soil losses derived by SfM and LS were rather similar. • SfM was applicable for morphological descriptions of relatively larger rills. • SfM had a generally higher accuracy in quantifying rill erosion with more fluctuating surface. [ABSTRACT FROM AUTHOR]

The upper reaches of the Hanjiang River Basin (HM-CSNWTP) is the headwater source for the middle route of China's South-to-North Water Transfer Project (M-CSNWTP), as well as the north-south transitional zone of central China, and is characterized by high precipitation sensitivity and variability. Changes in precipitation patterns can affect the potential runoff generation capacity of the HM-CSNWTP. Therefore, this study was focused on exploring the dynamic precipitation patterns over the HM-CSNWTP and the potential runoff generation capacity of this region at annual and seasonal timescales. Daily precipitation data from 34 meteorological stations for the period 1961–2016 were collected in order to estimate 4 categories of rainfall indices: average daily precipitation on all days (ADP) and on rainy days (ARP), total amount (TP), and rainy days (TD). The non-parametric Mann-Kendall test, LOWESS smoothing, and collaborative kriging method were implemented. The statistical results indicated that: (1) The annual ADP over the basin decreased slightly, at the rate of −0.22%/10a (−0.002 mm/d/a). Seasonally, summer ADP increased by 1.4%/10a (0.005 mm/d/a), while decreasing ADP values were detected in other seasons. Large increases in annual and summer ARP were found, at rates of 3.73%/10a (0.018 mm/d/a) and 3.72%/10a (0.039 mm/d/a), over the HM-CSNWTP, mainly in the southwestern area (Region III), due to the large changes of annual and summer ARP. Annual and summer ARP increased at significant rates of 7.22%/10a (0.034 mm/d/a) and 10.64%/10a (0.083 mm/d/a), respectively. (2) Decreasing light rainfall amounts (TP 0-10) and days (TD 0-10), and increasing heavy rainfall amounts (TP >25) and days (TD >25) were detected over the HM-CSNWTP, especially for Region III, in which TP >25 and TD >25 increased by 7.00%/10a (1.076 mm/a) and 5.37%/10a (0.023 d/a), respectively. (3) In the wettest assumption scenario, the estimated annual, spring, summer, autumn, and winter runoff depths were 912.9 mm, 183.0 mm, 410.6 mm, 259.0 mm, and 60.3 mm, respectively. In the driest assumption, the estimated annual, spring, summer, autumn, and winter runoff depths were 131.4 mm, 35.6 mm, 65.7 mm, 27.8 mm, and 2.3 mm, respectively, and the planned diversion water accounted for 76.1%, 63.2%, 70.0%, 102.2%, and 156.5% of the annual and seasonal driest assumption runoff depths, respectively. Thus, the water diversion of the M-CSNWTP in the driest assumption may trigger water shortages and environmental disasters in the lower reaches of the Hanjiang River Basin, especially at annual, autumn, and winter timescales. These findings provide some basic information for local water resource management in the HM-CSNWTP. • Average daily precipitation decreased by −0.22%/10a (−0.002 mm/d/a), while the precipitation intensity increased at the significant rate of 3.73%/10a (0.018 mm/d/a) over the basin from 1961–2016. • Decreasing light rainfall amounts and days, and increasing heavy rainfall amounts and days were detected over the HM-CSNWTP. • Annual potential runoff generation capacity over the HM-CSNWTP in the wettest and driest assumption years were 912.9 mm and 131.4 mm, respectively. [ABSTRACT FROM AUTHOR]

• The best soil quality indicators of erosion properties were rainfall, bulk density, Ks, and SPR. • Bulk density increased with time due to consolidation following wetting/drying cycles. • The Ks decreased rapidly to a fairly stable value by the fifth wetting/drying cycle. • SPR initially increased following the 1st wetting/drying cycle then decreased to a stable value. • Changes in soil erosion properties in response to soil consolidation are soil-specific. Consolidation of soil by wetting and drying cycles following tillage rapidly changes the soil physical properties but little is known about how these changes impact soil erosion. The objective of this study was to develop equations to predict soil erodibility (K d) and critical shear stress (τ c) in response to consolidation based upon changes in soil bulk density, saturated hydraulic conductivity, water content, soil penetration strength and surface shear strength following a series of wetting and drying cycles. Air-dried soil from four contrasting soil series was loosely filled into 20 soil cylinders (80 total) to simulate freshly tilled conditions. Soil physical and erosion properties were determined at six time periods (0, 1, 3, 5, 7, 10 days) following daily simulated rainfall of 33 mm h−1 for 1 h and 24 h of drainage/drying. The Jet Test device was used to determine K d , and τ c. The bulk density increased with time due to consolidation following the simulated precipitation events with the largest increase (50–100 % of the total) occurring after the first wetting/drying cycle. The Onstad consolidation model tended to over-predict this initial surface bulk density increase, whereas, an exponential model better represented the surface and depth-averaged bulk density changes for the four soils tested. The shear strength and soil penetration resistance increased dramatically after the first wetting/drying cycle then decreased to a fairly stable value in response to subsequent wetting/drying cycles. The saturated hydraulic conductivity, K s , decreased so rapidly with accumulated rainfall that an exponential decay model could not match the decrease in K s as the soil consolidated. The best indicators of erodibility response to consolidation were accumulated rain, surface bulk density, saturated hydraulic conductivity and soil penetration resistance at the 1.3 cm depth. The best indicators of critical shear stress were accumulated rainfall, soil penetration resistance at 1.3 cm and saturated hydraulic conductivity. Because these erosion parameters had intercepts that were dependent upon the soil series, prediction of changes in soil erosion with time following tillage will be soil-specific. [ABSTRACT FROM AUTHOR]

Hepatitis E virus (HEV) is a worldwide zoonotic and public health concern. The study of HEV biology is helpful for designing viral vaccines and drugs. Nanobodies have recently been considered appealing materials for viral biological research. In this study, a Bactrian camel was immunized with capsid proteins from different genotypes (1, 3, 4, and avian) of HEV. Then, a phage library (6.3 × 108 individual clones) was constructed using peripheral blood lymphocytes from the immunized camel, and 12 nanobodies against the truncated capsid protein of genotype 3 HEV (g3-p239) were screened. g3-p239-Nb55 can cross-react with different genotypes of HEV and block Kernow-C1/P6 HEV from infecting HepG2/C3A cells. To our knowledge, the epitope recognized by g3-p239-Nb55 was determined to be a novel conformational epitope located on the surface of viral particles and highly conserved among different mammalian HEV isolates. Next, to increase the affinity and half-life of the nanobody, it was displayed on the surface of ferritin, which can self-assemble into a 24-subunit nanocage, namely, fenobody-55. The affinities of fenobody-55 to g3-p239 were ∼20 times greater than those of g3-p239-Nb55. In addition, the half-life of fenobody-55 was nine times greater than that of g3-p239-Nb55. G3-p239-Nb55 and fenobody-55 can block p239 attachment and Kernow-C1/P6 infection of HepG2/C3A cells. Fenobody-55 can completely neutralize HEV infection in rabbits when it is preincubated with nonenveloped HEV particles. Our study reported a case in which a nanobody neutralized HEV infection by preincubation, identified a (to our knowledge) novel and conserved conformational epitope of HEV, and provided new material for researching HEV biology., (Copyright © 2024 by The American Association of Immunologists, Inc.)

Polyurethane (PU) is the sixth most used plastic in the world. Because many PU derived materials are thermosets and the monomers are valuable, chemical recycling to recover the polyol component is the most viable pathway to utilizing postconsumer PU waste in a closed-loop fashion. Acidolysis is an effective method to recover polyol from PU waste. Previous studies of PU acidolysis rely on the use of dicarboxylic acid (DCA) in high temperature reactions (>200 °C) in the liquid phase and result in unwanted byproducts, high energy consumption, complex separations of excess organic acid, and an overall process that is difficult to scale up. In this work, we demonstrate selective PU acidolysis with DCA vapor to release polyol at temperatures below the melting points of the DCAs (<150 °C). Notably, acidolysis with DCA vapor adheres to the principles of green chemistry and prevents in part esterification of the polyol product, eliminating the need for additional hydrolysis/processing to obtain the desired product. The methodology was successfully applied to a commercial PU foam (PUF) postconsumer waste.

Hepatitis E virus (HEV) is the most common cause of acute viral hepatitis worldwide, responsible for approximately 20 million infections annually. Among the three open reading frames (ORFs) of the HEV genome, the ORF3 protein is involved in virus release. However, the host proteins involved in HEV release need to be clarified. In this study, a host protein, thioredoxin domain-containing protein 5 (TXNDC5), interacted with the non-palmitoylated ORF3 protein by co-immunoprecipitation analysis. We determined that the overexpression or knockdown of TXNDC5 positively regulated HEV release from the host cells. The 17 FCL 19 mutation of the ORF3 protein lost the ability to interact with TXNDC5. The releasing amounts of HEV with the ORF3 mutation (FCL17-19SSP) were decreased compared with wild-type HEV. The overexpression of TXNDC5 can stabilize and increase ORF3 protein amounts, but not the TXNDC5 mutant with amino acids 1-88 deletion. Meanwhile, we determined that the function of TXNDC5 on the stabilization of ORF3 protein is independent of the Trx-like domains. Knockdown of TXNDC5 could lead to the degradation of ORF3 protein by the endoplasmic reticulum (ER)-associated protein degradation-proteasome system. However, the ORF3 protein cannot be degraded in the knockout-TXNDC5 stable cells, suggesting that it may hijack other proteins for its stabilization. Subsequently, we found that the other members of protein disulfide isomerase (PDI), including PDIA1, PDIA3, PDIA4, and PDIA6, can increase ORF3 protein amounts, and PDIA3 and PDIA6 interact with ORF3 protein. Collectively, our study suggested that HEV ORF3 protein can utilize TXNDC5 for its stability in ER to facilitate viral release., Importance: Hepatitis E virus (HEV) infection is the leading cause of acute viral hepatitis worldwide. After the synthesis and modification in the cells, the mature ORF3 protein is essential for HEV release. However, the host protein involved in this process has yet to be determined. Here, we reported a novel host protein, thioredoxin domain-containing protein 5 (TXNDC5), as a chaperone, contributing to HEV release by facilitating ORF3 protein stability in the endoplasmic reticulum through interacting with non-palmitoylated ORF3 protein. However, we also found that in the knockout-TXNDC5 stable cell lines, the HEV ORF3 protein may hijack other proteins for its stabilization. For the first time, our study demonstrated the involvement of TXNDC5 in viral particle release. These findings provide some new insights into the process of the HEV life cycle, the interaction between HEV and host factors, and a new direction for antiviral design., Competing Interests: The authors declare no conflict of interest.

Chemical recycling of polyurethane (PU) waste is essential to displace the need for virgin polyol production and enable sustainable PU production. Currently, less than 20% of PU waste is downcycled through rebinding to lower value products than the original PU. Chemical recycling of PU waste often requires significant input of materials like solvents and slow reaction rates. Here, we report the fast (<10 min) and solvent-free acidolysis of a model toluene diisocyanate (TDI)-based flexible polyurethane foam (PUF) at <200 °C using maleic acid (MA) with a recovery of recycled polyol (repolyol) in 95% isolated yield. After workup (hydrolysis of repolyl ester and separations), the repolyol exhibits favorable physical properties that are comparable to the virgin polyol; these include 54.1 mg KOH/g OH number and 624 cSt viscosity. Overall, 80% by weight of the input PUF is isolated into two clean-cut fractions containing the repolyol and toluene diamine (TDA). Finally, end-of-life (EOL) mattress PUF waste is recycled successfully with high recovery of repolyol using MA acidolysis. The solvent-free and fast acidolysis with MA demonstrated in this work with both model and EOL PUF provides a potential pathway for sustainable and closed-loop PU production., Competing Interests: The authors declare the following competing financial interest(s): A.S., T.F., P.G., and N.H. are employees of The Dow Chemical Company., (© 2024 The Authors. Published by American Chemical Society.)

We develop and demonstrate how to use the Graphical Unitary Group Approach (GUGA)-based MRCISD with Core-Valence Separation (CVS) approximation to compute the core-excited states. First, perform a normal Self-Consistent-Field (SCF) or valence MCSCF calculation to optimize the molecular orbitals. Second, rotate the optimized target core orbitals and append to the active space, form an extended CVS active space, and perform a CVS-MCSCF calculation for core-excited states. Finally, construct the CVS-MRCISD expansion space and perform a CVS-MRCISD calculation to optimize the CI coefficients based on the variational method. The CVS approximation with GUGA-based methods can be implemented by flexible truncation of the Distinct Row Table. Eliminating the valence-excited configurations from the CVS-MRCISD expansion space can prevent variational collapse in the Davidson iteration diagonalization. The accuracy of the CVS-MRCISD scheme was investigated for excitation energies and compared with that of the CVS-MCSCF and CVS-CASPT2 methods using the same active space. The results show that CVS-MRCISD is capable of reproducing well-matched vertical core excitation energies that are consistent with experiments by combining large basis sets and a rational reference space. The calculation results also highlight the fact that the dynamic correlation between electrons makes an undeniable contribution in core-excited states., (© 2024 Author(s). Published under an exclusive license by AIP Publishing.)

Vaccination is the most effective method to protect humans and animals from diseases. Anti-idiotype vaccines are safer due to their absence of pathogens. However, the commercial production of traditional anti-idiotype vaccines using monoclonal and polyclonal antibodies (mAb and pAb) is complex and has a high failure rate. The present study designed a novel, simple, low-cost strategy for developing anti-idiotype vaccines with nanobody technology. We used porcine circovirus type 2 (PCV2) as a viral model, which can result in serious economic loss in the pig industry. The neutralizing mAb-1E7 (Ab1) against PCV2 capsid protein (PCV2-Cap) was immunized in the camel. And 12 nanobodies against mAb-1E7 were screened. Among them, Nb61 (Ab2) targeted the idiotype epitope of mAb-1E7 and blocked mAb-1E7's binding to PCV2-Cap. Additionally, a high-dose Nb61 vaccination can also protect mice and pigs from PCV2 infection. Epitope mapping showed that mAb-1E7 recognized the 75 NINDFL 80 of PCV2-Cap and 101 NYNDFLG 107 of Nb61. Subsequently, the mAb-3G4 (Ab3) against Nb61 was produced and can neutralize PCV2 infection in the PK-15 cells. Structure analysis showed that the amino acids of mAb-1E7 and mAb-3G4 respective binding to PCV2-Cap and Nb61 were also similar on the amino acids sequences and spatial conformation. Collectively, our study first provided a strategy for producing nanobody-based anti-idiotype vaccines and identified that anti-idiotype nanobodies could mimic the antigen on amino acids and structures. Importantly, as more and more neutralization mAbs against different pathogens are prepared, anti-idiotype nanobody vaccines can be easily produced against the disease with our strategy, especially for dangerous pathogens.IMPORTANCEAnti-idiotype vaccines utilize idiotype-anti-idiotype network theory, eliminating the need for external antigens as vaccine candidates. Especially for dangerous pathogens, they were safer because they did not contact the live pathogenic microorganisms. However, developing anti-idiotype vaccines with traditional monoclonal and polyclonal antibodies is complex and has a high failure rate. We present a novel, universal, simple, low-cost strategy for producing anti-idiotype vaccines with nanobody technology. Using a neutralization antibody against PCV2-Cap, a nanobody (Ab2) was successfully produced and could mimic the neutralizing epitope of PCV2-Cap. The nanobody can induce protective immune responses against PCV2 infection in mice and pigs. It highlighted that the anti-idiotype vaccine using nanobody has a very good application in the future, especially for dangerous pathogens., Competing Interests: The authors declare no conflict of interest.

Porcine reproductive and respiratory syndrome (PRRS) is a serious global pig industry disease. Understanding the mechanism of viral replication and developing efficient antiviral strategies are necessary for combating with PRRS virus (PRRSV) infection. Recently, nanobody is considered to be a promising antiviral drug, especially for respiratory viruses. The present study evaluated two nanobodies against PRRSV nucleocapsid (N) protein (PRRSV-N-Nb1 and -Nb2) for their anti-PRRSV activity in vitro and in vivo . The results showed that intracellularly expressed PRRSV-N-Nb1 significantly inhibited PRRSV-2 replication in MARC-145 cells (approximately 100%). Then, the PRRSV-N-Nb1 fused with porcine IgG Fc (Nb1-pFc) as a delivering tag was produced and used to determine its effect on PRRSV-2 replication in porcine alveolar macrophages (PAMs) and pigs. The inhibition rate of Nb1-pFc against PRRSV-2 in PAMs could reach >90%, and it can also inhibit viral replication in vivo . Epitope mapping showed that the motif Serine 105 (S105) in PRRSV-2 N protein was the key amino acid binding to PRRSV-N-Nb1, which is also pivotal for the self-interaction of N protein via binding to Arginine 97. Moreover, viral particles were not successfully rescued when the S105 motif was mutated to Alanine (S105A). Attachment, entry, genome replication, release, docking model analysis, and blocking enzyme-linked immunosorbent assay (ELISA) indicated that the binding of PRRSV-N-Nb1 to N protein could block its self-binding, which prevents the viral replication of PRRSV. PRRSV-N-Nb1 may be a promising drug to counter PRRSV-2 infection. We also provided some new insights into the molecular basis of PRRSV N protein self-binding and assembly of viral particles.IMPORTANCEPorcine reproductive and respiratory syndrome virus (PRRSV) causes serious economic losses to the swine industry worldwide, and there are no highly effective strategies for prevention. Nanobodies are considered a promising novel approach for treating diseases because of their ease of production and low costing. Here, we showed that PRRSV-N-Nb1 against PRRSV-N protein significantly inhibited PRRSV-2 replication in vitro and in vivo . Furthermore, we demonstrated that the motif Serine 105 (S105) in PRRSV-N protein was the key amino acid to interact with PRRSV-N-Nb1 and bond to its motif R97, which is important for the self-binding of N protein. The PRRSV-N-Nb1 could block the self-interaction of N protein following viral assembly. These findings not only provide insights into the molecular basis of PRRSV N protein self-binding as a key factor for viral replication for the first time but also highlight a novel target for the development of anti-PRRSV replication drugs., Competing Interests: The authors declare no conflict of interest.

Topography is an important factor affecting soil erosion and is measured as a combination of the slope length and slope steepness (LS-factor) in erosion models, like the Chinese Soil Loss Equation. However, global high-resolution LS-factor datasets have rarely been published. Challenges arise when attempting to extract the LS-factor on a global scale. Furthermore, existing LS-factor estimation methods necessitate projecting data from a spherical trapezoidal grid to a planar rectangle, resulting in grid size errors and high time complexity. Here, we present a global 1-arcsec resolution LS-factor dataset (DS-LS-GS1) with an improved method for estimating the LS-factor without projection conversion (LS-WPC), and we integrate it into a software tool (LS-TOOL). Validation of the Himmelblau-Orlandini mathematical surface shows that errors are less than 1%. We assess the LS-WPC method on 20 regions encompassing 5 landform types, and R 2 of LS-factor are 0.82, 0.82, 0.83, 0.83, and 0.84. Moreover, the computational efficiency can be enhanced by up to 25.52%. DS-LS-GS1 can be used as high-quality input data for global soil erosion assessment., (© 2024. The Author(s).)

Hepatitis E virus (HEV) is a zoonotic pathogen that is widespread worldwide. At present, most enzyme-linked immunosorbent assay (ELISA) kits only detect antibodies against human HEV. In this study, a nanobody-horseradish peroxidase (HRP) fusion protein-based competitive ELISA (cELISA) with more convenience and spectral characteristics for HEV antibody detection was developed and used to detect HEV IgG in various species. First, 6 anti-swine HEV capsid protein nanobodies were screened using phage display technology from an immunized Bactrian camel. Then, HEV-Nb67-HRP fusions were expressed and used as a probe for developing a cELISA. The cutoff value of the cELISA was 17.8%, and there was no cross-reaction with other anti-swine virus antibodies, suggesting that the cELISA had good specificity. The intra-assay and interassay coefficients of variation (CVs) were 1.33 to 5.06% and 1.52 to 6.84%, respectively. The cELISA and Western blot showed a higher coincidence rate (97.14%, kappa value = 0.927) than cELISA and indirect ELISA (95.00%, kappa value = 0.876) in clinical swine serum samples. Finally, the seroprevalence of HEV IgG in humans, pigs, rabbits, cows, and goats was 30.67%, 19.26%, 8.75%, 27.59%, and 18.08%, respectively, suggesting that cELISA may have a broader scale for mammalian HEV antibody detection. These results suggest that the newly developed cELISA was rapid, low-cost, reliable, and useful for the serological evaluation of current HEV. IMPORTANCE HEV is thought to be a zoonotic infection and is widespread worldwide; it is beneficial to establish a more convenient and spectral method for HEV antibody detection. In this study, a convenient, time-saving, reproducible, highly sensitive, specific, and novel nanobody-based cELISA was developed and can be used to detect IgG antibodies against mammalian HEV. It provides a new technique for serological evaluation and ELISA-based diagnosis of HEV infection., Competing Interests: The authors declare no conflict of interest.

Circulation of influenza A virus (IAV), especially within poultry and pigs, continues to threaten public health. A simple and universal detecting method is important for monitoring IAV infection in different species. Recently, nanobodies, which show advantages of easy gene editing and low cost of production, are a promising novel diagnostic tool for the monitoring and control of global IAVs. In the present study, five nanobodies against the nucleoprotein of H9N2 IAV were screened from the immunized Bactrian camel by phage display and modified with horseradish peroxidase (HRP) tags. Out of which, we determined that H9N2-NP-Nb5-HRP can crossreact with different subtypes of IAVs, and this reaction is also blocked by positive sera for antibodies against different IAV subtypes. Epitope mapping showed that the nanobody-HRP fusion recognized a conserved conformational epitope in all subtypes of IAVs. Subsequently, we developed a nanobody-based competitive ELISA (cELISA) for detecting anti-IAV antibodies in different species. The optimized amount of coating antigen and dilutions of the fusion and testing sera were 100 ng/well, 1:4000, and 1:10, respectively. The time for operating the cELISA was approximately 35 min. The cELISA showed high sensitivity, specificity, reproducibility, and stability. In addition, we found that the cELISA and hemagglutination inhibition test showed a consistency of 100% and 87.91% for clinical and challenged chicken sera, respectively. Furthermore, the agreement rates were 90.4% and 85.7% between the cELISA and commercial IEDXX ELISA kit. Collectively, our developed nanobody-HRP fusion-based cELISA is an ideal method for monitoring IAV infection in different species., Competing Interests: Conflict of interest The authors declare that they have no conflicts of interest with the contents of this article., (Copyright © 2022 The Authors. Published by Elsevier Inc. All rights reserved.)

Hepatitis E virus (HEV) is thought to be a zoonotic pathogen that causes serious economic loss and threatens human health. However, there is a lack of efficient antiviral strategies. As a more promising tool for antiviral therapy, nanobodies (also named single-domain antibodies, sdAbs) exhibit higher specificity and affinity than traditional antibodies. In this study, nanobody anti-genotype four HEV open reading frame 2 (ORF2) was screened using phage display technology, and two nanobodies (nb14 and nb53) with high affinity were prokaryotically expressed. They were identified to block HEV ORF2 virus like particle (VLP) sp239 (aa 368-606) absorbing HepG2 cells in vitro . With the previously built animal model, the detection indicators of fecal shedding, viremia, seroconversion, alanine aminotransferase (ALT) levels, and liver lesions showed that nb14 could completely protect rabbits from swine HEV infection, and nb53 partially blocked swine HEV infection in rabbits. Collectively, these results revealed that nb14, with its anti-HEV neutralizing activity, may be developed as an antiviral drug for HEV., Competing Interests: 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., (Copyright © 2022 Chen, Wang, Zhang, Li, Gao, Nan, Zhao, Zhou and Liu.)

Background: Hepatitis E virus (HEV) genotypes 3 and 4 are zoonotic. In this study, HEV infection in laboratory Bama miniature pigs in Sichuan Province of China was investigated. Firstly, one hundred rectal swabs were collected for HEV RNA testing, and chose positive samples for sequence analysis. Concurrently, for pathogenicity study, six healthy Bama miniature pigs were randomly divided into two groups of 3 pigs each. A total of 500 μL of HEV stock (positive fecal samples identified in this study) was inoculated intravenously into each pig in the experimental group, and the three pigs in the other group served as negative controls. Serum and fecal samples were collected at 1 to 10 weeks post-inoculation (wpi) for alanine aminotransferase (ALT) levels, anti-HEV antibodies and HEV RNA detection, respectively. During necropsies, liver lesions and HEV antigen in liver were observed at 10 wpi., Results: The rate of fecal sample HEV RNA-positivity was 12% (12/100). Sequence comparisons indicated that partial ORF1 and ORF2 gene sequences of this isolate shared highest identities with corresponding sequences of genotype 4a HEV isolates (81.4%-96.1% and 89.9%-97.1%, respectively). Phylogenetic tree analysis further demonstrated that sequences of this isolate clustered together with sub-genotype 4a HEV isolate sequences. Experimentally, the pathogenicity of Bama miniature pigs infected with this isolate exhibited viremia, fecal virus shedding, seroconversion, ALT level increasing, liver lesions and HEV antigen in liver., Conclusions: This is the first study to confirm that HEV is currently circulating in laboratory Bama miniature pigs in China and this isolate can successfully infect Bama miniature pigs experimentally. More importantly, this study suggested HEV screening of laboratory pigs should be conducted to prevent research personnel from acquiring zoonotic HEV infections., (© 2022. The Author(s).)

While soil erosion drives land degradation, the impact of erosion on soil microbial communities and multiple soil functions remains unclear. This hinders our ability to assess the true impact of erosion on soil ecosystem services and our ability to restore eroded environments. Here we examined the effect of erosion on microbial communities at two sites with contrasting soil texture and climates. Eroded plots had lower microbial network complexity, fewer microbial taxa, and fewer associations among microbial taxa, relative to non-eroded plots. Soil erosion also shifted microbial community composition, with decreased relative abundances of dominant phyla such as Proteobacteria, Bacteroidetes, and Gemmatimonadetes. In contrast, erosion led to an increase in the relative abundances of some bacterial families involved in N cycling, such as Acetobacteraceae and Beijerinckiaceae. Changes in microbiota characteristics were strongly related with erosion-induced changes in soil multifunctionality. Together, these results demonstrate that soil erosion has a significant negative impact on soil microbial diversity and functionality., (© 2021. The Author(s), under exclusive licence to International Society for Microbial Ecology.)

To determine the relationship between decreased egg production and avian HEV infection, thirty healthy 23-week-old Hy-Line Variety Brown layer hens were randomly divided into 3 groups with 10 hens per group. Next, a genotype 3 avian HEV strain from China was used to inoculate laying hens via oronasal or intravenous routes using a 50% chicken infectious dose of 500. All hens were necropsied at 14 weeks postinoculation (wpi). Fecal virus shedding, viremia, seroconversion, serum alanine aminotransferase (ALT) increases and liver lesions showed that after intravenous (i.v.) and oronasal inoculation, the laying hens were successfully infected. Compared with the uninoculated group, the i.v. and oronasally inoculated groups exhibited egg production decreases at 1wpi and 2wpi, reaching peak production at 3wpi and 8wpi, respectively. In both groups, decreased production was evident for 12 weeks and overall decreases ranged from 10% to 30%. In addition, in the 7 field layer farms exhibiting decreased egg production, vaccination regimens had been completed against Newcastle disease, infectious bronchitis, avian influenza H9N2 and H5N1 and egg drop syndrome virus. However, circulating avian HEV was confirmed on these farms using tests to detect avian HEV IgG antibodies and RNA. Therefore, the experimental and field data indicate that avian HEV infection acting alone could account for observed decreases in egg production in laying hens., (Copyright © 2017 Elsevier B.V. All rights reserved.)

To understand the relationship between plant community succession and soil nutrient dynamics is crucial in intervening vegetation succession. This paper reported the results from a study carried out in a forest-steppe zone on the Loess Plateau, with emphasis on the vegetation characteristics and soil nutrient dynamics duringvegetation restoration on abandoned farmlands of this area. The results showed that under zonal habitat conditions, natural vegetation succession would turn toward the original vegetation communities, but the expected shrub or trees communities didn't occur after 40 approximately 50 years, and Stipa bungeana, Artemisia sacrorum, Bothriochloa ischaemun, Stipa grandis and Lespedeza davurica communities were still the widely distributed communities. Vegetation restoration had a significant effect on soil nutrient dynamics. In general, soil nutrient contents increased with restoration time, and extremely significant changes occurred in soil organic matter, total N, available N, and available K (P< 0.001),while only significant changes in available P (0.05 < P < 0.01) and no significant change in total P (P > 0.05). Moreover, the changes were also found in soil profile. Statistical analysis showed that from surface layer (0 approximately 20 cm) to deeper layer (to 60 cm), extremely significant changes occurred in soil organic matter, total N, available N, available K and available P (P < 0.001), and significant change in total P (P< 0.05). Soil nutrients intended to accumulate in surface layer. Further linear correlation analysis showed that soil organic matter, total N, available N and available K were significantly correlated each other ( P< 0.001), but didn't show correlation with soil total P and available P.

The ALMANAC model was validated in a drought-stressed year and in a period from 1989 to 1998 at different sites of Texas to evaluate its ability in simulating maize and sorghum yields at different spatial scales and to extend its application range. There were 11 sites for maize and 8 sites for sorghum in plot-size simulations, and 9 counties for maize and sorghum in county level simulations. The model showed similar accuracy in simulating both plot-size and county level mean grain yields. It could also simulate single-year yields under water-limited climatic conditions for several sites and mean county yields of maize and sorghum, and had small CV values of mean yields for a long-term prediction. The mean error was 8.9% for sorghum and 9.4% for maize in field scale simulations, and was only 2.6% for maize and-0.6% for sorghum in county level mean yield simulations. Crop models often require extensive input data sets to realistically simulate crop growth. The development of such input data sets is difficult for some model users. The soil, weather, and crop parameter data sets developed in this study could be used as the guidelines for model applications in similar climatic regions and on similar soils.

Objective: To study the effects of the bone matrix gelatin and composite of bone morphogenetic protein and fibrin glue (BMP-FG) on the repair of thyroid cartilage defect., Method: Full-thickness defects measuring 0.4 cm x 0.4 cm were created in four sections in thyroid cartilages of 20 adult dogs. The defects were divided into 4 groups by the sections they in. Group A was empty group, without implant; Group B were repaired by implanted with hydroxylapatite; Group C with bone matrix gelatin (containing BMP); Group D with bone morphogenetic protein-fibrin glue composite. The animals were killed separately at 2, 4, 12 weeks after operation. The effects of repair were analyzed by routine histological examination and electron microscope., Result: In the BMP-FG implanted group, the result showed complete absorption of the implant and substitution by new-formed cartilage and bone. The defects in the BMG group regenerated less cartilage and bone, the inflammation was sever. The gross appearance and histological features of HA group were similar to the empty group., Conclusion: Both BMP-FG and BMG can induce cartilage and bone regeneration to repair the defect of thyroid cartilage. BMP-FG has a better effect.

Vegetation cover and land management are the main limiting factors of soil erosion, and quantitative evaluation on the effect of different vegetation on soil erosion is essential to land use and soil conservation planning. The vegetation cover and management factor (C) in the universal soil loss equation (USLE) is an index to evaluate this effect, which has been studied deeply and used widely. However, the C factor study is insufficient in China. In order to strengthen the research of C factor, this paper reviewed the developing progress of C factor, and compared the methods of estimating C value in different USLE versions. The relative studies in China were also summarized from the aspects of vegetation canopy coverage, soil surface cover, and root density. Three problems in C factor study were pointed out. The authors suggested that cropland C factor research should be furthered, and its methodology should be unified in China to represent reliable C values for soil loss prediction and conservation planning.

Wind erosion is becoming a constraining factor to agriculture and animal husbandry in the arid and semiarid area of Luanhe River. In this paper, wind erosion process was studied through simulation experiments. The results showed that soil humidity and vegetation coverage were the main factors affecting wind erosion. The wind erosion rate was decreased with increasing soil humidity and vegetation coverage, and hence, wind erosion process was reduced by modulating soil humidity and vegetation coverage in human activities.