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The first-principles was employed to calculate the adsorption of Cs on (2 × 2) Al(Mg)0.5Ga0.5N and Al0.5 Ga(Mg)0.5N surfaces using density-functional theory within a plane-wave ultrasoft pseudopotential scheme. Then, the surface morphology, stability, work functions and Cs adsorptions of Al(Mg)0.5Ga0.5N and Al0.5 Ga(Mg)0.5N surfaces were investigated. The results reveal that Al(Mg)0.5Ga0.5N surface with Mg in the first layer was more suitable for ultraviolet cathode. The most stable adsorption site for adsorption of Cs on the Al(Mg)0.5Ga0.5N surface was found on N top. With the increase of Cs coverage, the interaction between Cs and atoms in the first layer of surface and that between Cs and Cs was enhanced, the surface dipole moment increased, the work function decreased, the carrier concentration and the absorption in visible light increased. When Cs coverage was greater than 0.5ML, the adsorption of Cs reached saturation, the deformation of surface structure appeared, the adsorption in visible light was greater than that in UV, and the surface was no longer suitable for UV detection. The results show that 0.5ML is the turning point of Cs coverage for the surface doped with Mg. [ABSTRACT FROM AUTHOR]

A common variant (rs53576, G/A) in the oxytocin receptor (OXTR) gene is associated with individual differences in social behavior and may increase the risk for neuropsychiatric disorders characterized by social impairment, especially autism. Although recent functional magnetic resonance imaging (fMRI) studies have identified functional connectivity alteration in some brain regions in risk A allele carriers, it is currently unknown whether this dysfunctional connectivity causes disruption of the topological properties of brain functional networks. We applied a graph-theoretical analysis to investigate the topological properties of brain networks derived from resting-state fMRI in relation to AA homozygotes versus G allele carriers in 290 cognitive normal young adults. We found both AA homozygotes and G allele carriers demonstrated small-world properties; however, male AA homozygotes showed lower normalized clustering coefficient, small-worldness, and local efficiency compared with male G allele carriers, no differences survived after Bonferroni correction; and the inter-group differences of all three metrics exhibited an allele-load-dependent trend (AA < AG < GG), indicating a randomization shift of their brain functional networks. No significant results were observed in any global measures in female AA homozygotes as compared to female G allele carriers. Our results suggested that the topological patterns of brain functional networks were altered in OXTR rs53576 male homozygotes for the risk A allele compared with male G allele carriers, providing evidence for the disruption of integrity in large-scale intrinsic brain networks in a sex-dimorphic manner. [ABSTRACT FROM AUTHOR]

In this study, a novel fluorescent "turn-on" aptasensor was developed for sensitive and rapid detection of tetracycline (TC) in animal-derived food. It is based on aptamer-functionalized nitrogen-doped graphene quantum dots (N-GQDs-aptamer) coupled with cobalt oxyhydroxide (CoOOH) nanoflakes. The CoOOH nanoflakes are efficient fluorescence quenchers in homogeneous solutions, and this is due to their advantages of excellent optical properties, superior flexibility, and water dispersibility. The proposed method's mechanism is driven by quenching based on the fluorescence resonance energy transfer (FRET) between the donor (N-GQDs) and the acceptor (CoOOH nanoflakes). On the other hand, fluorescence recovery is caused by the structure switching behavior of the aptamer. Compared with previous methods, our developed method exhibits better behavior in terms of being easy to fabricate and being simple in detection procedure and maintains the detection limit low enough in TC determination: a linear range from 1 to 100 ng mL−1 and a detection limit of 0.95 ng mL−1 (S/N = 3). Furthermore, the proposed method was applied to five animal-derived food samples (milk, honey, fish, eggs, and chicken muscle) and demonstrated practical applicability. As well, the method has the advantages of simplicity in pre-treatment and convenience in instruments, saves times, and is cost-effective. Finally, the proposed method demonstrates significant potential for sensitive and rapid detection of specific components in real samples. [ABSTRACT FROM AUTHOR]

This paper introduces a weak Galerkin (WG) finite element method for the Stokes equations in the primal velocity-pressure formulation. This WG method is equipped with stable finite elements consisting of usual polynomials of degree k≥1 for the velocity and polynomials of degree k−1 for the pressure, both are discontinuous. The velocity element is enhanced by polynomials of degree k−1 on the interface of the finite element partition. All the finite element functions are discontinuous for which the usual gradient and divergence operators are implemented as distributions in properly-defined spaces. Optimal-order error estimates are established for the corresponding numerical approximation in various norms. It must be emphasized that the WG finite element method is designed on finite element partitions consisting of arbitrary shape of polygons or polyhedra which are shape regular. [ABSTRACT FROM AUTHOR]

The online anomaly detection has been propounded as the key idea of monitoring fault of large-scale sensor nodes in Internet of Things. Now, the exciting progresses of research have been made in online anomaly detection area. However, the highly dynamic distributing character of Internet of Things makes the anomaly detection scheme difficult to be used in online manner. This paper presents a new online anomaly learning and detection mechanism for large-scale service of Internet of Thing. Firstly, our model uses the reversible-jump MCMC learning to online learn anomaly-free of dynamics network and service data. Next, we perform a structural analysis of IoT-based service topology by network utility maximization theory. The results of experiment demonstrate the method accuracy in forecasting dynamics network and service structures from synthetic data. [ABSTRACT FROM AUTHOR]

The coordinated learning is importance of technique for cooperative multi-objects system in large-scale Internet of Things . The coordinated learning has attracted a lot of attention for its applications in Internet of Things. However, the self-adaptive makes the coordinated learning difficult to be used in IoT. This paper proposes multi-objects scalable coordinated learning algorithm based on the maximum potential loss of coordination. The algorithm defines an interaction measure that allows objects to dynamically estimate the potential utility loss of coordination with any cluster of objects. The interaction mechanism makes each object compute their beneficial coordination set in different situations and makes the best use of their limited communication resource in Internet of Things. As a result of experiments, our algorithm adapts policy learning of object and their coordination network for different context. Finally, the experiments with the smart agriculture data set demonstrate that the proposed scheme is effective and robust. [ABSTRACT FROM AUTHOR]

A common variant (rs53576) of the OXTR gene has been implicated in a number of socio-emotional phenotypes, such as anxiety-related behavior. Previous studies have demonstrated that A-allele carriers have higher levels of physiological and dispositional stress reactivity and depressive symptomatology compared to those with the GG genotype, but the mediating neural mechanisms remain poorly understood. We combined voxel-based morphometry and resting-state functional connectivity analyses in a large cohort of healthy young Chinese Han individuals to test the hypothesis that the OXTR gene polymorphism influences an anxiety-related temperamental trait, as assessed by the harm avoidance subscale from the Tridimensional Personality Questionnaire via modulating the gray matter volume and resting-state functional connectivity of the brain, especially the limbic system. We revealed that female subjects with the AA genotype showed increased harm avoidance scores relative to G-carrier females. We also found that, compared to female individuals with the GG/GA genotype, female individuals with the AA genotype exhibited significantly smaller amygdala volumes bilaterally (especially the centromedial subregion), with a trend of allele-load-dependence. Compared to female individuals with the GG/GA genotype, female subjects with the AA genotype demonstrated reduced resting-state functional coupling between the prefrontal cortex and amygdala bilaterally, also with an allele-load-dependent trend. Furthermore, the magnitude of prefrontal-amygdala coupling in the left hemisphere was positively correlated with harm avoidance scores in female subjects. Our findings highlight a possible neural pathway by which a naturally occurring variation of the OXTR gene may affect an anxiety-related temperamental trait in female subjects by modulating prefrontal-amygdala functional connectivity. [ABSTRACT FROM AUTHOR]

Perennial ryegrass ( Lolium perenne L.) and Italian ryegrass ( Lolium multiflorum Lam.) are important temperate forage grasses which are closely related, generating fertile interspecific hybrids. All groups are represented by multiple cultivars in the commercial pasture seeds market. Due to the close taxonomic relationship between the two species, differentiation based on morphophysiological criteria is not always readily achievable. In addition, an obligate outbreeding reproductive habit produces high levels of individual heterozygosity and intrapopulation diversity, which presents problems for discrimination between cultivars. Molecular genetic marker polymorphism provides an effective means of addressing these challenges. An iterative process of resequencing from loci distributed across the perennial ryegrass genome was used to identify single nucleotide polymorphism (SNP) markers, which were then validated and formatted in a highly multiplexed (384-plex) assay system. SNP genotyping was then performed across samples of 48-192 individuals from a total of 27 ryegrass cultivars (19 of perennial ryegrass, seven of Italian ryegrass and one hybrid cultivar). SNP markers from perennial ryegrass exhibited a high level of transfer to Italian ryegrass. Data analysis permitted quantification of intra- and inter-species diversity, as well as discrimination between cultivars within each species, including diploid and autotetraploid cultivars of perennial ryegrass. Lower levels of SNP-based diversity were detected in Italian ryegrass than in perennial ryegrass. A neighbour-joining tree based on genetic distance analysis located a hybrid cultivar to an intermediate position between the two species-specific cultivar groups. The resulting catalogue of ryegrass cultivars will provide support for the processes of cultivar accreditation and quality assurance. [ABSTRACT FROM AUTHOR]

The weak Galerkin finite element method is a novel numerical method that was first proposed and analyzed by Wang and Ye () for general second order elliptic problems on triangular meshes. The goal of this paper is to conduct a computational investigation for the weak Galerkin method for various model problems with more general finite element partitions. The numerical results confirm the theory established in Wang and Ye (). The results also indicate that the weak Galerkin method is efficient, robust, and reliable in scientific computing. [ABSTRACT FROM AUTHOR]

In the east of Xiaolangdi, many river terraces are developed at the exit of the Yellow River Gorges. Among them the terraces in Kouma, Yanshi of Henan Province are most typical, where the Yellow River developed three staircase terraces, among which the altitude of gravel stratum of the topmost terrace is 30-35 m higher than the river level. The top of the gravel stratum was covered by 60 m eolian loess deposits which have many brownish-red paleosol strips. And the paleosol S14 is at its bottom. Research on systematic magnetostratigraphy and paleosol-loess matching indicates that the bottom age of the loess on the topmost terrace is 1165 ka. Therefore, it can be concluded that the terrace develops no later than 1.165 Ma and the situation that the Yellow River runs through Sanmen Gorges and inpours into East China Sea happened at least before 1.165 Ma. [ABSTRACT FROM AUTHOR]

It is shown that there exists an elementary vortex topological current in the modified two-dimensional Gross–Pitaevskii theory. An explicit expression for the vortex velocity field as a function of the order parameter is derived. The evolution of vortices is studied from the topological properties of the order parameter field. It is found that vortices generate or annihilate at the limit points and encounter, split, or merge at the bifurcation points of the order parameter field ψ. [ABSTRACT FROM AUTHOR]

Purpose: To develop and validate a prediction model based on imaging data for the prognosis of mild chronic subdural hematoma undergoing atorvastatin treatment. Methods: We developed the prediction model utilizing data from patients diagnosed with CSDH between February 2019 and November 2021. Demographic characteristics, medical history, and hematoma characteristics in non-contrast computed tomography (NCCT) were extracted upon admission to the hospital. To reduce data dimensionality, a backward stepwise regression model was implemented to build a prognostic prediction model. We calculated the area under the receiver operating characteristic curve (AUC) of the prognostic prediction model by a tenfold cross-validation procedure. Results: Maximum thickness, volume, mean density, morphology, and kurtosis of the hematoma were identified as the most significant predictors of good hematoma dissolution in mild CSDH patients undergoing atorvastatin treatment. The prediction model exhibited good discrimination, with an area under the curve (AUC) of 0.82 (95% confidence interval [CI], 0.74–0.90) and good calibration (p = 0.613). The validation analysis showed the AUC of the final prognostic prediction model is 0.80 (95% CI 0.71–0.86) and it has good prediction performance. Conclusion: The imaging data-based prediction model has demonstrated great prediction accuracy for good hematoma dissolution in mild CSDH patients undergoing atorvastatin treatment. The study results emphasize the importance of imaging data evaluation in the management of CSDH patients. [ABSTRACT FROM AUTHOR]

It is found that the fluorescence of carbon dots (CD) with an emission peak at 459 nm is strongly quenched by silver nanoparticles (AgNPs) with their absorption peak at 430 nm. The finding was applied in a fluorescence quenchometric lateral flow immunochromatographic assay for detection of zearalenone (ZEN) with CDs conjugated to ovalbumin (OVA) as donor signal probe and AgNP-Ab as acceptor signal probe. The assay has an LOD of 0.1 μg·L−1 for ZEN. This is 10 times better than the respective “turn-off” AgNP-based LFIA. In case of cereal samples and their products, the LODs range from 1 to 2.5 μg·kg−1. Only minor cross reactivity is found for fusarium toxins, and no cross-sensitivity for aflatoxin B1, T-2 mycotoxin, ochratoxin A, deoxynivalenol, and fumonisin B1. The assay represents a simple, sensitive, and rapid tool for determination of ZEN in cereal samples and their products.Schematic presentation of fluorescence quenching lateral flow immunochromatographic assay (FLFIA) based on carbon dots (CD) and silver nanoparticle (AgNP) fluorescence resonance energy transfer (FRET) system for the rapid high sensitive detection of zearalenone (ZEN) in cereal samples. [ABSTRACT FROM AUTHOR]

Folic acid (FA) is an essential vitamin in humans, and thus, rapid, accurate, and sensitive methods for its quantification in different biological samples are needed. This work describes a novel, simple, and effective dual-emission fluorescence nanoprobe for FA detection and quantification. The probe was covalently linked to amino-modified orange quantum dots (QDs) and carboxyl-modified blue graphene quantum dots (GQDs). The resulting material exhibited two emission peaks at 401 and 605 nm upon excitation at 310 nm. The probe had good selectivity and sensitivity toward FA with an exceptionally low detection limit (LOD = 0.09 nM). This probe was effectively used to quantify FA in animal serum samples. The method has potential utility for FA analysis in different types of biological samples. [ABSTRACT FROM AUTHOR]

Purpose: With the escalating social pressures, there has been a continuous rise in the prevalence of depression among the population, leading to substantial healthcare burdens. Moreover, conventional pharmacological interventions still exhibit certain limitations. Therefore, the primary objective of this study is to systematically evaluate the clinical efficacy of probiotics in the treatment of depression. Methods: Randomized controlled trials of probiotics in treating depressive symptoms were retrieved from Pubmed, Cochrane Library, Web of Science, Wan Fang database, and CNKI between the establishment of the database and March 2022. The primary outcome was Beck's depression rating scale (BDI) scores, while the secondary outcomes were depression scores on the DASS-21 scale, biochemical indicators (IL-6, NO, and TNF-α levels), and adverse events. In addition, Revman 5.3 was used for Meta-analysis and quality evaluation, and Stata 17 was used for the Egger test and Begg's test. A total of 776 patients, including 397 and 379 patients in the experimental and control groups, respectively, were included. Results: The total BDI score of the experimental group was lower than that of the control group (MD = − 1.98, 95%CI − 3.14 to − 0.82), and the score of DASS (MD = 0.90, 95%CI − 1.17 to 2.98), the IL-6 level (SMD = − 0.55, 95%CI − 0.88 to − 0.23), the NO level (MD = 5.27, 95% CI 2.51 to 8.03), and the TNF-α level (SMD = 0.19, 95% CI − 0.25 to 0.63). Conclusion: The findings substantiate the therapeutic potential of probiotics in mitigating depressive symptoms by significantly reducing Beck's Depression Inventory (BDI) scores and alleviating the overall manifestation of depression. [ABSTRACT FROM AUTHOR]

An introduction to the journal is presented in which the editor discusses various reports within the issue on topics concerning computational mathematics.

Background: Brain death (BD), the irreversible cessation of function in the whole brain, is a well-known condition in most countries. The criteria and practical guidelines for brain death determination (BDD) in China were issued by the Brain Injury Evaluation Quality Control Center (BQCC) of the National Health and Family Planning Commission in 2013. Thereafter, we proposed a plan called the three-step quality control plan (three-step QCP) to ensure the safety and consistency of the clinical judgments regarding BD. By retrospectively reviewing this plan, we aimed to identify problems during its implementation and to provide suggestions for future work on quality control for BDD. Methods: Data were retrieved from the BQCC database. The characteristics and test results of physicians undergoing a BDD training course and the BD case records submitted by hospitals before and after receiving accreditation were analyzed. Results: In the first step of the plan, the error rate for physicians undergoing the BDD paper test was highest for limb movement discrimination (26.29%); this error rate was correlated with age (per 10-year increase) (odds ratio = 1.262, 95% confidence interval 1.067–1.491, P = 0.007) but was nonsignificantly associated with sex, specialty category, professional level, and hospital level (P > 0.05). During the second step of the plan, the highest percentage of problems was associated with apnea testing (22.75%), followed by ancillary testing of BDD (16.17%). In the last step, the highest percentage of problems in the case records was associated with apnea testing (41.73%). Conclusions: The three-step QCP is of significant utility for ensuring accuracy and appropriateness in BDD. Simultaneously, this study provides important evidence for advancing quality control for BDD in the next stage. [ABSTRACT FROM AUTHOR]

Purpose: Seroma formation is the most common cause of morbidity associated with laparoscopic inguinal hernia repair. This study aimed to examine the relationship between the thickness of subcutaneous fat (TSF) and the risk of postoperative seroma.We reviewed data from a prospective cohort of 229 male patients who underwent laparoscopic total extra-peritoneal (TEP) hernioplasty for indirect inguinal hernia between August 2018 and July 2021. The TSF was assessed using preoperative ultrasound images. The risk factors for postoperative seroma were determined using univariate and multivariate logistic regression models.Postoperative seromas occurred in 26 patients (11.4%). The factors associated with postoperative seroma included longer hernia duration, larger hernia defects, extension into the scrotum, and greater TSF (P < 0.05). In multivariate analysis, a greater TSF was independently associated with a greater risk of postoperative seroma (per 1 mm: odd ratio [OR] 1.105, 95% confidence interval [CI] 1.048–1.165, P < 0.001; TSF ≥ 26.0 mm: OR 7.033, 95% CI 2.485–19.901, P < 0.001). Similar results were obtained in the subgroup analysis. The area under the curve of TSF for predicting seroma formation was 0.703 (95% CI 0.601–0.806).Ultrasound-derived TSF may be a promising prognostic factor for postoperative seroma in patients undergoing laparoscopic TEP repair. Further validation is required and then this parameter can be used to improve decision-making process.Methods: Seroma formation is the most common cause of morbidity associated with laparoscopic inguinal hernia repair. This study aimed to examine the relationship between the thickness of subcutaneous fat (TSF) and the risk of postoperative seroma.We reviewed data from a prospective cohort of 229 male patients who underwent laparoscopic total extra-peritoneal (TEP) hernioplasty for indirect inguinal hernia between August 2018 and July 2021. The TSF was assessed using preoperative ultrasound images. The risk factors for postoperative seroma were determined using univariate and multivariate logistic regression models.Postoperative seromas occurred in 26 patients (11.4%). The factors associated with postoperative seroma included longer hernia duration, larger hernia defects, extension into the scrotum, and greater TSF (P < 0.05). In multivariate analysis, a greater TSF was independently associated with a greater risk of postoperative seroma (per 1 mm: odd ratio [OR] 1.105, 95% confidence interval [CI] 1.048–1.165, P < 0.001; TSF ≥ 26.0 mm: OR 7.033, 95% CI 2.485–19.901, P < 0.001). Similar results were obtained in the subgroup analysis. The area under the curve of TSF for predicting seroma formation was 0.703 (95% CI 0.601–0.806).Ultrasound-derived TSF may be a promising prognostic factor for postoperative seroma in patients undergoing laparoscopic TEP repair. Further validation is required and then this parameter can be used to improve decision-making process.Results: Seroma formation is the most common cause of morbidity associated with laparoscopic inguinal hernia repair. This study aimed to examine the relationship between the thickness of subcutaneous fat (TSF) and the risk of postoperative seroma.We reviewed data from a prospective cohort of 229 male patients who underwent laparoscopic total extra-peritoneal (TEP) hernioplasty for indirect inguinal hernia between August 2018 and July 2021. The TSF was assessed using preoperative ultrasound images. The risk factors for postoperative seroma were determined using univariate and multivariate logistic regression models.Postoperative seromas occurred in 26 patients (11.4%). The factors associated with postoperative seroma included longer hernia duration, larger hernia defects, extension into the scrotum, and greater TSF (P < 0.05). In multivariate analysis, a greater TSF was independently associated with a greater risk of postoperative seroma (per 1 mm: odd ratio [OR] 1.105, 95% confidence interval [CI] 1.048–1.165, P < 0.001; TSF ≥ 26.0 mm: OR 7.033, 95% CI 2.485–19.901, P < 0.001). Similar results were obtained in the subgroup analysis. The area under the curve of TSF for predicting seroma formation was 0.703 (95% CI 0.601–0.806).Ultrasound-derived TSF may be a promising prognostic factor for postoperative seroma in patients undergoing laparoscopic TEP repair. Further validation is required and then this parameter can be used to improve decision-making process.Conclusion: Seroma formation is the most common cause of morbidity associated with laparoscopic inguinal hernia repair. This study aimed to examine the relationship between the thickness of subcutaneous fat (TSF) and the risk of postoperative seroma.We reviewed data from a prospective cohort of 229 male patients who underwent laparoscopic total extra-peritoneal (TEP) hernioplasty for indirect inguinal hernia between August 2018 and July 2021. The TSF was assessed using preoperative ultrasound images. The risk factors for postoperative seroma were determined using univariate and multivariate logistic regression models.Postoperative seromas occurred in 26 patients (11.4%). The factors associated with postoperative seroma included longer hernia duration, larger hernia defects, extension into the scrotum, and greater TSF (P < 0.05). In multivariate analysis, a greater TSF was independently associated with a greater risk of postoperative seroma (per 1 mm: odd ratio [OR] 1.105, 95% confidence interval [CI] 1.048–1.165, P < 0.001; TSF ≥ 26.0 mm: OR 7.033, 95% CI 2.485–19.901, P < 0.001). Similar results were obtained in the subgroup analysis. The area under the curve of TSF for predicting seroma formation was 0.703 (95% CI 0.601–0.806).Ultrasound-derived TSF may be a promising prognostic factor for postoperative seroma in patients undergoing laparoscopic TEP repair. Further validation is required and then this parameter can be used to improve decision-making process. [ABSTRACT FROM AUTHOR]

Background: Bone marrow-derived cells (BMDCs) have the ability to differentiate into intestinal epithelial cells after transplantation and participate in the regeneration process of damaged epithelium.Aims: To investigate whether BMDCs could differentiate into intestinal epithelium long term in chimeric mice after transplantation and without special treatment.Methods: Forty irradiated C57BL/6 mice were used. Thirty of them (group A) received transplantation of BMDCs from GFP transgenic mice, and ten (group B) received PBS. The chimeric percentage at the 14th month was examined by flow cytometry. Engraftment of BMDCs was detected by immunohistochemistry in intestinal epithelium. Immunofluorescence observation was used to detect coexpression of PCK, CD45 and Chromogranin A with GFP. BMDCs in the epithelium were observed by an immune electron microscope. The percent of GFP(+) epithelial cells was also determined by flow cytometry.Results: Mice in group A had a survival rate of 93.3% 1 week after transplantation. BMDCs could engraft into recipients' intestinal epithelium. These cells expressed epithelial cell marker PCK, but could not express CD45. Some of them differentiated into enteroendocrine cells expressing Chromogranin A. GFP(+) villous epithelial cells ranged from 9.41 to 16.07% in different subgroups of group A. BMDCs in epithelium developed the characteristics of enterocytes and goblet cells. GFP(+)/PCK(+) epithelial cells at the 6th month made up a proportion of 16.11% among all the isolated epithelial cells.Conclusions: Long term, BMDCs could repopulate recipient's intestinal epithelium even without any special treatment, which suggests a novel insight into the maintenance of the intestinal epithelial constitution. [ABSTRACT FROM AUTHOR]

Saxitoxin (STX) as one of the most harmful and typical paralytic shellfish toxins, is posing a serious threat to environmental and human health, thus it is essential to develop a sensitive and reliable analytical method for STX detection. Herein, we proposed a strategy for rapid and sensitive detection of STX with surface-enhanced Raman spectroscopy (SERS), by employing cysteine modified gold nanoparticles (Cys-AuNPs) as SERS probe to capture STX molecules through electrostatic interactions and multiple hydrogen bonds between Cys and STX molecules. Moreover, the XPS and zeta potential results indicated that Cys could bond to AuNPs through Au-S bonds and the addition of STX could induce the efficient aggregation of Cys-AuNPs owing to the presence of electrostatic interactions and multiple hydrogen bonds between Cys and STX molecules. Furthermore, considering the high sensitivity and stability of the dynamic surface-enhanced Raman spectroscopy (D-SERS) strategy with the formation of a 3D hotspot matrix, the highly sensitive detection of STX was realized to a level of 1 × 10−7 M by using the D-SERS strategy. Consequently, Cys-AuNPs as high affinity substrates can provide high sensitivity for the detection of STX through the D-SERS strategy. [ABSTRACT FROM AUTHOR]

Cyanide (C≡N) can lead to blood, cardiovascular system, and nervous system disorders owing to the acute and chronic toxicity; thus, aiming at the group or individual poisoning incidents, it is necessary to develop the sensitive and credible method for rapid on-site detection of poisons cyanide. Surface-enhanced Raman spectroscopy (SERS) with the advantages of providing fingerprint information of target molecules and single-molecules sensitivity has been widely used in on-site analysis; however, the SERS measurements always suffer from the problem of the stability of substrates. Here, the polyvinylpyrrolidone (PVP)-stabilized Au NPs (PVP-Au NPs) have been assembled through the simple, convenient evaporation-induced strategy with the large-scale hotspots substrates. The presence of PVP can not only facilitate the assembly of Au NPs but also prevent the corrosion of CN− towards the Au NPs with the formation of [Au (CN)2]−1, providing high stable and reproducible SERS signals. Moreover, the PVP-Au NPs have been assembled on the Si wafer to fabricate the portable SERS chip for rapid on-site detection of CN− with an RSD of 5.8% and limitation of 100 ppb. Furthermore, by coupling a portable Raman spectrometer, the SERS spectra of CN− spiked into different specimens to simulate the poison samples have been collected and analyzed on SERS chips with the recovery of 89–103% and RSD not higher than 11.3%. Consequently, the fabricated SERS chip with assembled PVP-Au NPs can provide sensitive and credible detection for CN− in different specimens, and then would satisfy the rapid on-site evaluation of CN− in poisoning incidents with the portable Raman spectrometer. [ABSTRACT FROM AUTHOR]

A colorimetric microplate assay for determination of Staphylococcus aureus DNA is described. Linear padlock probes were designed to recognize target sequences. After DNA binding, the linear padlock probes were circularized by ligation and then hybridize with biotin-labeled capture probes. Biotin-labeled capture probes act as primers to initiate the RCA. The biotin-labeled RCA products hybridize with digoxin-labeled signal probes fixed on streptavidin-functionalized wells of a 96-well plate. To enhance sensitivity, an AuNP-anti-digoxigenin-POx-HRP conjugate was added to the wells and then bound to digoxin-labeled signalling probes. The oxidation of tetramethylbenzidine (TMB) by H2O2 produces a color change from colorless to blue via HRP catalysis. After the reaction was terminated, absorbance is measured at 450 nm. For target sequences of Staphylococcus aureus, the detection limit is 1.2 pM. For genomic DNA, the detection limit is 7.4 pg.μL−1. The potential application of the method was verified by analyzing spiked food samples. [ABSTRACT FROM AUTHOR]

The authors describe two kinds of immunochromatographic assays. The first is based on the use of dyed polymer microspheres (MICA), the another on the use of quantum dots (QICA). Both enable visual detection of enrofloxacin (ENR) in animal tissue and milk. Both the MICA and the QICA have visual limits of detection of 1 μg·L when working in buffer, of 5 μg·kg in case of animal tissue, and of 10 μg·L in case of milk. Other quinolones do not interfere. The MICA and QICA described here are convenient and fairly rapid in that the detection process (including sample pretreatment and assay) takes 20 min only which is far less than the commercial enzyme-linked immunosorbent assay (ELISA) test kit which requires 120 min. The MICA and QICA are more sensitive than the immunochromatographic assay using colloidal gold labels and the same polyclonal antibody. The results of analysis of spiked samples via MICA and QICA are in good agreement with those obtained by the commercial ELISA test kit. [ABSTRACT FROM AUTHOR]

dTMP-GH is a chimeric protein containing a tandem dimer of thrombopoietin mimetic peptide (dTMP) fused to human growth hormone (hGH) prepared previously by our team. It shows significant bioactivity in promoting thrombocytopoiesis, but detection of intact dTMP-GH in plasma is still a challenge due to the presence of endogenous hGH. In this study, a rabbit polyclonal antibody with high affinity to dTMP was obtained with a BSA-conjugated immunogen composed of 20 amino acids sequence spanning two TMP and the linker. A monoclonal antibody termed as 3B2 was screened out by using immunizing mice with whole dTMP-GH, which was proved to simultaneously interact with rhGH, TMP-GH, and dTMP-GH, respectively. In this study, we developed a specific and sensitive sandwich enzyme-linked immunosorbent assay (ELISA) with two antibodies (one polyclonal and one HRP-conjugated monoclonal) to quantify dTMP-GH. The polyclonal antibody and HRP-conjugated monoclonal antibody 3B2 were applied as the capture antibody and detection antibody, respectively. A good correlation between ELISA and bicinchoninic acid (BCA) assay in the quantification of diluted dTMP-GH was observed (r = 0.996). Meanwhile, the standard curve of this ELISA method was found in a linear relationship between 0.2 and 10 ng/mL in the presence of rabbit plasma. In vivo experiments demonstrate that the newly developed method is effective to detect dTMP-GH in rabbits, which paves the way for further pharmacokinetic evaluation. [ABSTRACT FROM AUTHOR]

Chlamydomonas reinhardtii offers a great promise for large-scale production of multiple recombinant proteins of pharmaceutical and industrial interest. However, the nuclear-encoding transgenes usually are expressed at a low level, which severely hampers the use of this alga in molecular farming. In this study, the promoter of the endogenous intraflagellar transport 25 (IFT25) gene of C. reinhardtii was tested for its ability to drive the expression of green fluorescent protein (GFP), which functions as a readout for target gene expression . IFT25 promoter (IFT25P) alone was not able to drive GFP expression to a detectable level. IFT25P, however, can drive robust IFT25-GFP fusion protein expression when the intron-containing IFT25 gene was inserted between IFT25P and GFP cDNA. When an extended version of foot-and-mouth virus 2A protease (2A) sequence was further inserted between the intron-containing IFT25 gene and the GFP cDNA, discrete GFP protein was observed to release from the IFT25-2A-GFP polyprotein via 2A self-cleaving with a cleavage efficacy of approximately 99%. The monomer GFP was accumulated to a level of as high as 0.68% of total soluble proteins. To test whether the newly developed bicistronic IFT25P-IFT25-2A expression system can be used to overexpress heterologous proteins of different origins and sizes, we inserted codon-optimized cDNAs encoding a Trichoderma reesei xylanase1 (25 kDa) and a Lachnospiraceae bacterium ND2006 type V CRISPR-Cas protein LbCpf1 (147 kDa) to the vector and found that the production of xylanase1 and LbCpf1 was as high as 0.69 and 0.49% of total soluble protein. Our result showed that IFT25P-IFT25-2A system is more efficient to drive nuclear gene expression in C. reinhardtii than other conventionally used promoters, thus representing a novel efficient recombinant protein expression tool and has the potential to be scaled for commercial production of nuclear-encoded recombinant proteins of different sizes and origins in C. reinhardtii. [ABSTRACT FROM AUTHOR]

Renal interstitial fibrosis is a major pathologic feature of diabetic nephropathy, while the pathogenesis and therapeutic interventions of diabetic renal interstitial fibrosis are not well established. In this study, we first demonstrated that high glucose could induce renal fibroblast (NRK-49F) cell proliferation and activation to myofibroblasts, accompanied by a significant increase in the intracellular levels of reactive oxygen species (ROS) derived from nicotinamide adenine dinucleotide phosphate oxidase 4 (NOX4). ROS-mediated ERK1/2 activation was found to play a crucial role in high glucose-induced fibroblast proliferation and activation. Resveratrol, like the NOX4-targeting small interfering RNA (siRNA), markedly inhibited high glucose-induced fibroblast proliferation and activation by reducing NOX4-derived ROS production. It was then revealed that the increase in the expression of NOX4 induced by high glucose was due to the inactivation of AMP-activated protein kinase (AMPK), which could be reversed by resveratrol. Further in vivo investigation demonstrated that resveratrol treatment significantly attenuated renal fibrosis in db/db mice, accompanied by an evident increase in phospho-AMPK and decrease in NOX4. In summary, our results suggest that high glucose can directly promote renal fibroblasts proliferation and activation in a ROS-dependent manner, and resveratrol is a potential therapeutic agent against diabetic renal fibrosis via regulation of AMPK/NOX4/ROS signaling. Key message: [ABSTRACT FROM AUTHOR]

Key message: A targeted amplicon-based genotyping-by-sequencing approach has permitted cost-effective and accurate discrimination between ryegrass species (perennial, Italian and inter-species hybrid), and identification of cultivars based on bulked samples. Abstract: Perennial ryegrass and Italian ryegrass are the most important temperate forage species for global agriculture, and are represented in the commercial pasture seed market by numerous cultivars each composed of multiple highly heterozygous individuals. Previous studies have identified difficulties in the use of morphophysiological criteria to discriminate between these two closely related taxa. Recently, a highly multiplexed single nucleotide polymorphism (SNP)-based genotyping assay has been developed that permits accurate differentiation between both species and cultivars of ryegrasses at the genetic level. This assay has since been further developed into an amplicon-based genotyping-by-sequencing (GBS) approach implemented on a second-generation sequencing platform, allowing accelerated throughput and ca. sixfold reduction in cost. Using the GBS approach, 63 cultivars of perennial, Italian and interspecific hybrid ryegrasses, as well as intergeneric Festulolium hybrids, were genotyped. The genetic relationships between cultivars were interpreted in terms of known breeding histories and indistinct species boundaries within the Lolium genus, as well as suitability of current cultivar registration methodologies. An example of applicability to quality assurance and control (QA/QC) of seed purity is also described. Rapid, low-cost genotypic assays provide new opportunities for breeders to more fully explore genetic diversity within breeding programs, allowing the combination of novel unique genetic backgrounds. Such tools also offer the potential to more accurately define cultivar identities, allowing protection of varieties in the commercial market and supporting processes of cultivar accreditation and quality assurance. [ABSTRACT FROM AUTHOR]

The 14-mer thrombopoietin mimetic peptide (TMP), especially in the form of dimer, displayed potent megakaryocytopoiesis activity in vitro. However, it is difficult to prepare such short peptide with high bioactivity through gene-engineering approaches. In this study, a chimeric protein containing a tandem dimer of TMP (dTMP) fused to human growth hormone (hGH), a kind of hematopoietic growth factor that activates the same signal pathways as thrombopoietin, was produced in Escherichia coli by soluble expression. By rational utilization of the XmnI and EcoRV restriction sites, a PCR fragment encoding dTMP-GH was inserted into the plasmid vector pMAL-p2X at the position right after Xa factor cleavage site, in frame with maltose-binding protein (MBP) gene. Under optimized conditions, a high-level expression of soluble MBP-dTMP-GH fusion protein was obtained. By application of amylose resin chromatography, Xa factor digestion, hydrophobic chromatography followed by gel filtration, the dTMP-GH fusion protein was separated. Finally, a relatively high yield of dTMP-GH fusion protein with high purity (>98 %) and without redundant amino acid was achieved, as identified by high-performance liquid chromatography, mass spectrometry, and amino acid sequencing. The functional assays showed that dTMP-GH could promote the proliferation of megakaryoblast cells and maturation of murine megakaryocytes derived from bone marrow, in a dose-dependent manner. Moreover, an enhanced effect of dTMP-GH on megakaryocytopoiesis was found as compared with equimolar concentration of dTMP and rhGH. This work provides a new avenue to generate thrombopoietic agents based on TMP. [ABSTRACT FROM AUTHOR]

Perennial ryegrass is a globally cultivated obligate outbreeding diploid species (2 n = 2 x = 14) which is subjected to periods of waterlogging stress due to flood irrigation during winter and the lead-up to summer. Reduction of oxygen supply to root systems due to waterlogging produces consequent deleterious effects on plant performance. Framework genetic maps for a large-scale genetic mapping family [ F(NA × AU)] were constructed containing 91 simple sequence repeat and 24 single nucleotide polymorphism genetic markers. Genetic trait dissection using both control and waterlogging treatments was performed in the glasshouse, a total of 143 maximally recombinant genotypes being selected from the overall sib-ship and replicated threefold in the trial. Analysis was performed for nine quantitative morphological traits measured 8 weeks after stress treatments were applied. A total of 37 quantitative trait loci (QTLs) were identified; 19 on the NA parental genetic map, and 18 on the AU parental genetic map. Regions of particular interest were identified on linkage groups (LGs) 4 and 3 of the respective maps, which have been targeted for further analysis by selection of critical recombinants. This first study of genetic control of waterlogging tolerance in ryegrasses has important implications for breeding improvement of abiotic stress adaptation. [ABSTRACT FROM AUTHOR]

Mesenchymal stem cells (MSCs) are multipotent cells, which can differentiate into different tissues. It is still controversial whether MSCs can be isolated from adult peripheral blood (PB) under normal conditions and whether they can be mobilized in a way similar to that of hematopoietic stem cells (HSCs). In this study, rat MSCs circulating in the PB under normal conditions can be isolated and cultured, and MSCs from PB and BM can be mobilized by LiCL. The mobilized MSCs can be induced to differentiate into neuron by such factors as β-mercaptoethanol and supernatants of nerve cell cultures. The present study provides a broader perspective on the repair of neural trauma. [ABSTRACT FROM AUTHOR]

A fluorometric aptamer-based method is described for the determination of aflatoxin B1 (AFB1). The fluorescent dye thioflavin T (ThT) forms a complex with the aptamer against AFB1 (aptamer/ThT), and the fluorescence of the complex is strongly enhanced. On addition of AFB1, it will bind to the aptamer and release ThT. The fluorescence of free ThT is much weaker. The fluorescence of the system, best measured at excitation/emission wavelengths of 440/487 nm, drops gradually in the AFB1 concentration range from 0.2 to 200 ng·mL−1, exhibiting good linearity. The detection limits are 0.2 ng·mL−1 in buffer solution, and 1 ng·mL−1 when applied to plant-derived food. The recovery of AFB1 from spiked foodstuff ranges from 74.7% to 121%. The assay can be performed within 20 min. Graphical abstract Schematic presentation of label-free thioflavin T (ThT)-based fluorescence aptasensor using aflatoxin B1(AFB1) aptamer/ThT G-quadruplex complex and the AFB1 aptamer/AFB1 complex fluorescent signal system for the rapid and sensitive detection of AFB1 in soy sauce, spirits, rice, corn and peanuts. [ABSTRACT FROM AUTHOR]