Heterospecific eavesdropping on disturbance cues of a treefrog.

Alarm signals and cues are crucial to animal survival and vary greatly across species. Eavesdropping on heterospecific alarm signals and cues can provide eavesdroppers with information about potential threats. In addition to acoustic alarm signals, evidence has accumulated that chemical alarm cues and disturbance cues can also play a role in alerting conspecifics to potential danger in adult anurans (frogs and toads). However, there is very little known about whether disturbance cues are exploited by heterospecifics. In the present study, we conducted a binary choice experiment and a prey chemical discrimination experiment, respectively, to test the responses of a sympatric anuran species (red webbed treefrogs, Rhacophorus rhodopus) and a sympatric predator species (Chinese green tree vipers, Trimeresurus stejnegeri) to disturbance odors emitted by serrate-legged small treefrogs (Kurixalus odontotarsus). In the binary choice experiment, we found that the presence of disturbance odors did not significantly trigger the avoidance behavior of R. rhodopus. In the prey chemical discrimination experiment, compared with odors from undisturbed K. odontotarsus (control odors) and odorless control, T. stejnegeri showed a significantly higher tongue-flick rate in response to disturbance odors. This result implies that disturbance odor cues of K. odontotarsus can be exploited by eavesdropping predators to detect prey. Our study provides partial evidence for heterospecific eavesdropping on disturbance cues and has an important implication for understanding heterospecific eavesdropping on chemical cues of adult anurans.

[Relation between Chinese Medical Constitutions and Chemotherapy-induced Leucopenia in Breast Cancer Patients: a Clinical Study].

OBJECTIVE: To analyze the relationship between Chinese medical constitutions and chemotherapy-induced leucopenia (CIL) of primary breast cancer patients. METHODS: Totally 306 breast cancer patients undergoing adjunctive chemotherapy for the 1st time, and effective 291 breast cancer patients were recruited in this study.Nine Basic Constitutional Scale was used before first chemotherapy. Chinese medical constitutions were classified and quantitatively scored. The highest grading for any item of adverse reactions in each case during the whole chemotherapy course was recorded after chemotherapy. Data were statistically analyzed using SPSS16.0. RESULTS: There was no significant difference in CIL between different chemotherapy regimens and various Chinese medical constitutions of breast cancer patients (P > 0.05). Yang deficiency constitution is one risk factor for CIL. The higher the score of yang deficiency constitution, the more severe the CIL. CONCLUSIONS: Yang deficiency constitution was correlated with the degree of CIL. The higher the score of yang deficiency constitution, the greater the risk of III-IV grade CIL in breast cancer patients.

Immunogenicity and safety of an enterovirus 71 vaccine in healthy Chinese children and infants: a randomised, double-blind, placebo-controlled phase 2 clinical trial.

BACKGROUND: Enterovirus 71 (EV71) outbreaks are a socioeconomic burden, especially in the western Pacific region. Results of phase 1 clinical trials suggest an EV71 vaccine has a clinically acceptable safety profile and immunogenicity. We aimed to assess the best possible dose and formulation, immunogenicity, and safety profile of this EV71 vaccine in healthy Chinese children. METHODS: This randomised, double-blind, placebo-controlled, phase 2 trial was undertaken at one site in Donghai County, Jiangsu Province, China. Eligible participants were healthy boys or girls aged 6­36 months. Participants were randomly assigned (1:1:1:1:1) to receive either 160 U, 320 U, or 640 U alum-adjuvant EV71 vaccine, 640 U adjuvant-free EV71 vaccine, or a placebo (containing alum adjuvant only), according to a blocked randomisation list generated by SAS 9.1. Participants and investigators were masked to the assignment. The primary endpoint was anti-EV71 neutralising antibody geometric mean titres (GMTs) at day 56, analysed according to protocol. The study is registered with ClinicalTrials.gov, number NCT01399853. FINDINGS: We randomly assigned 1200 participants, 240 (120 aged 6­11 months [infants] and 120 aged 12­36 months [children]) of whom were assigned to each dose. 1106 participants completed the study and were included in the according-to-protocol analysis. The main reasons for dropout were withdrawal of consent and refusal to donate a blood sample. Infants who received the 640 U adjuvant vaccine had the highest GMTs on day 56 (742·2 [95% CI 577·3­954·3]), followed by those who received the 320 U formulation (497·9 [383·1­647·0]). For children, those who received the 320 U formulation had the highest GMTs on day 56 (1383·2 [1037·3­1844·5]). Participants who received the vaccine had significantly higher GMTs than did who received placebo (p<0·0001). For the subgroup of participants who were seronegative at baseline, both infants and children who received the 640 U adjuvant vaccine had the highest GMTs on day 56 (522·8 [403·9­676·6] in infants and 708·4 [524·1­957·6] in children), followed by those who received the 320 U adjuvant vaccine (358·2 [280·5­457·5] in infants and 498·0 [383·4­646·9] in children). 549 (45·8%) of 1200 participants (95 CI 42·9­48·6%) reported at least one injection-site or systemic adverse reaction, but the incidence of adverse reactions did not differ significantly between groups (p=0·36). The 640 U alum-adjuvant vaccine group had a significantly higher incidence of induration than did the 640 U adjuvant-free group (p=0·001). INTERPRETATION: Taking immunogenicity, safety, and production capacity into account, the 320 U alum-adjuvant formulation of the EV71 vaccine is probably the best possible formulation for phase 3 trials. FUNDING: The National Science and Technology Major Project (2011ZX10004-902) of the Chinese Ministry of Science and Technology, China's 12­5 National Major Infectious Disease Program (2012ZX10002-001), and Beijing Vigoo Biological.

Efficacy, safety, and immunology of an inactivated alum-adjuvant enterovirus 71 vaccine in children in China: a multicentre, randomised, double-blind, placebo-controlled, phase 3 trial.

BACKGROUND: A vaccine for enterovirus 71 (EV71) is needed to address the high burden of disease associated with infection. We assessed the efficacy, safety, immunogenicity, antibody persistence, and immunological correlates of an inactivated alum-adjuvant EV71 vaccine. METHODS: We did a randomised, double-blind, placebo-controlled, phase 3 trial. Healthy children aged 6-35 months from four centres in China were randomly assigned (1:1) to receive vaccine or alum-adjuvant placebo at day 0 and 28, according to a randomisation list (block size 30) generated by an independent statistician. Investigators and participants and their guardians were masked to the assignment. Primary endpoints were EV71-associated hand, foot, and mouth disease (HFMD) and EV71-associated disease during the surveillance period from day 56 to month 14, analysed in the per-protocol population. This study is registered with ClinicalTrials.gov, number NCT01508247. FINDINGS: 10,245 participants were enrolled and assigned: 5120 to vaccine versus 5125 to placebo. 4907 (with three cases of EV71-associated HFMD and eight cases of EV71-associated disease) versus 4939 (with 30 cases of EV71-associated HFMD and 41 cases of EV71-associated disease) were included in the primary efficacy analysis. Vaccine efficacy was 90·0% (95% CI 67·1-96·9) against EV71-associated HFMD (p=0·0001) and 80·4% (95% CI 58·2-90·8) against EV71-associated disease (p<0·0001). Serious adverse events were reported by 62 of 5117 (1·2%) participants in the vaccine group versus 75 of 5123 (1·5%) in the placebo group (p=0·27). Adverse events occurred in 3644 (71·2%) versus 3603 (70·3%; p=0·33). INTERPRETATION: EV71 vaccine provides high efficacy, satisfactory safety, and sustained immunogenicity. FUNDING: China's 12-5 National Major Infectious Disease Program, Beijing Vigoo Biological.

Silencing airway epithelial cell-derived hepcidin exacerbates sepsis induced acute lung injury.

INTRODUCTION: The production of antimicrobial peptides by airway epithelial cells is an important component of the innate immune response to pulmonary infection and inflammation. Hepcidin is a ß-defensin-like antimicrobial peptide and acts as a principal iron regulatory hormone. Hepcidin is mostly produced by hepatocytes, but is also expressed by other cells, such as airway epithelial cells. However, nothing is known about its function in lung infectious and inflammatory diseases. We therefore sought to investigate the role of airway epithelial cell-derived hepcidin in sepsis-induced acute lung injury. METHODS: Acute lung injury was induced by polymicrobial sepsis via cecal ligation and puncture (CLP) surgery. Adenovirus-mediated short hairpin RNA specific for the mouse hepcidin gene hepc1 and control adenovirus were intratracheally injected into mice. The adenovirus-mediated knockdown of hepcidin in airway epithelial cells was evaluated in vivo. Lung injury and the 7-day survival rate were assessed. The levels of hepcidin-related iron export protein ferroportin were measured, and the iron content and function of alveolar macrophages were evaluated. RESULTS: The hepcidin level in airway epithelial cells was upregulated during polymicrobial sepsis. The knockdown of airway epithelial cell-derived hepcidin aggravated the polymicrobial sepsis-induced lung injury and pulmonary bacterial infection and increased the mortality (53.33% in Ad-shHepc1 treated mice versus 12.5% in Ad-shNeg treated mice, P <0.05). The knockdown of hepcidin in airway epithelial cells also led to reduced ferroportin degradation and a low intracellular iron content in alveolar macrophages. Moreover, alveolar macrophages form the airway epithelial cell-derived hepcidin knockdown mice showed impaired phagocytic ability than those from the control mice. CONCLUSIONS: Airway epithelial cell-derived hepcidin plays an important role in CLP induced acute lung injury. The severe lung injury in the airway epithelial cell-derived hepcidin knockdown mice is at least partially related to the altered intracellular iron level and function of alveolar macrophages.

On the open problem related to rank equalities for the sum of finitely many idempotent matrices and its applications.

Tian and Styan have shown many rank equalities for the sum of two and three idempotent matrices and pointed out that rank equalities for the sum P1 + ⋯+P k with P1,…, P k be idempotent (k > 3) are still open. In this paper, by using block Gaussian elimination, we obtained rank equalities for the sum of finitely many idempotent matrices and then solved the open problem mentioned above. Extensions to scalar-potent matrices and some related matrices are also included.

A peptide selectively recognizes Gram-negative bacteria and forms a bacterial extracellular trap (BET) through interfacial self-assembly.

An innate immune system intricately leverages unique mechanisms to inhibit colonization of external invasive Bacteria, for example human defensin-6, through responsive encapsulation of bacteria. Infection and accompanying antibiotic resistance stemming from Gram-negative bacteria aggregation represent an emerging public health crisis, which calls for research into novel anti-bacterial therapeutics. Herein, inspired by naturally found host-defense peptides, we design a defensin-like peptide ligand, bacteria extracellular trap (BET) peptide, with modular design composed of targeting, assembly, and hydrophobic motifs with an aggregation-induced emission feature. The ligand specifically recognizes Gram-negative bacteria via targeting cell wall conserved lipopolysaccharides (LPS) and transforms from nanoparticles to nanofibrous networks in situ to trap bacteria and induce aggregation. Importantly, treatment of the BET peptide was found to have an antibacterial effect on the Pseudomonas aeruginosa strain, which is comparable to neomycin. Animal studies further demonstrate its ability to trigger aggregation of bacteria in vivo. This biomimetic self-assembling BET peptide provides a novel approach to fight against pathogenic Gram-negative bacteria.

Characterization of a new male sterility-related gene Camf1 in Capsicum annum L.

For the sake of screening novel genes related to the male sterility in chili pepper for studying the molecular mechanism of plant male sterility, the gene differential expression analysis was performed by cDNA-amplified fragment length polymorphism (cDNA-AFLP) in the genic male sterile-fertile line 114AB of Capsicum annum L., and a variety of differentially expressed cDNA fragments were detected in fertile or sterility material. Camf1, a transcript-derived fragment (TDF) accumulated in fertile line flower buds was further investigated. The Camf1 has 1,854 bp in length with no introns containing a 1,707-bp open reading frame (ORF). The deduced amino acid sequence of Camf1 shares higher similarity to some members from a glyoxal oxidase-related protein family, and has a glyoxal oxidase conserved domain at the N-terminus and a domain of unknown function (DUF1929) at C-terminal end. Expression analysis showed that Camf1 expressed only in stage 3-7 flower buds of male fertile of C. annum L. 114AB, and no detection in all organs of male sterility. The peak of expression level of Camf1 appeared at stage 4 flower buds of fertile line. Furthermore, expression analysis of different organs revealed that Camf1 expressed only in anthers of male fertile material and there were no expression in sepals, petals, pistils, roots, stems, leaves and open flowers. These results suggested that Camf1 was an anther-specific gene and might be essential for the fertility of C. annum L.

Nano-hydroxyapatite/ß-tricalcium phosphate ceramics scaffolds loaded with cationic liposomal ceftazidime: preparation, release characteristics in vitro and inhibition to Staphylococcus aureus biofilms.

In the current study, nano-hydroxyapatite/ß-tricalcium phosphate (HA/ß-TCP) ceramics scaffolds loaded with cationic liposomal ceftazidime (CLCs) prepared by modified reverse phase evaporation method, the investigations of their release characteristics were performed by the dissolution tests, in vitro anti-biofilm activity of the scaffolds was studied by the determination of bacterial susceptibility with ELISA. The mean particle size, zeta potential, pH and entrapment efficiency of the CLCs studied were 161.5 ± 5.37 nm, 60.60 ± 5.24 mV, 6.90 ± 0.07 and 16.57 ± 0.13%, respectively. Electron microscopic images of the samples indicated that the liposomes were well preserved in the scaffolds and that it was the CLCs rather than free ceftazidime releasing from the scaffolds. The minimal inhibitory concentrations (MICs) to Staphylococcus aureus of free ceftazidime and its liposomal formulation were 6.00 µg/mL and the release behaviors of both CLCs and free ceftazidime from scaffolds were based on the dissolution/diffusion processes, Fick's law. These results demonstrated that CLCs could inhibit remarkably the formation of S. aureus biofilm more effectively than free ceftazidime (P < 0.05). The study demonstrated that the HA/ß-TCP ceramic scaffolds was such a material that could sustain release CLCs and maintain the adequate amounts of CLCs to absorb to biofilm. It provided an ideal way to inhibit bacterial biofilms for clinical practices.

[Metabolomics study of the myocardial tissue of rats of cardiac blood stasis syndrome].

OBJECTIVE: To find out the metabolite profile of rats' myocardial tissue of cardiac blood stasis syndrome (CBSS), and to analyze the metabolic pathway of CBSS rats' myocardial tissue by observing the changes of phenotypes intervened by Yangxin Tongmai Recipe (YTR). METHODS: Acute myocardial infarction (AMI) rat model of CBSS was prepared by ligating the left anterior descending coronary artery. Meanwhile, the model was interfered with YTR. The metabolites of rats' myocardial tissue were detected in the model group, the YTR group, the sham-operation group, and the blank control group using GC-MS (8 rats in each group). Changes of metabolite contents were analyzed among different groups using principal component analysis (PCA) and least-square analysis. RESULTS: As for PCA: The results of PCA showed that principal component integral (PCI) of the four groups was mainly distributed in the three regions of oval scatterplot. The factor loading gram showed that contents of glycine, fumaric acid, malic acid, glutamic acid, glucose, phosphoric acid, galactopyranose, lysine were changed in the model group. Analysis of partial least square method: PLS regression model showed that obvious linear correlation existed between the model group and the YTR group, which proved the model was reasonably established. The drug intervention was highly positively correlated with glycine, malic acid, glutamic acid, glucose, highly correlated with urea and butanedioic acid, but negatively correlated with lysine. According to VIP value, each variable was closely correlated with the drug intervention in sequence as malic acid, glutamic acid, glycine, glucose, fumaric acid, urea, galactose, tyrosine, lactic acid, and alanine. Results of variability analysis: Obvious changed variability analysis of metabolite difference showed that 10 metabolites such as glycine, etc. obviously decreased in the model group, showing significant difference when compared with the normal group (P<0.01). Compared with the model group, contents of glycine, fumaric acid, malic acid, glutamic acid, glucose, tyrosine,urea, lactic acid, and alanine, etc. obviously increased after drug intervention (P<0.01). Of them, the increment of malic acid, glumatic acid, tyrosine, and urea was less, showing significant difference when compared with that of the normal group. The mean of lysine was slightly lowered after drug intervention, but with insignificant difference when compared with that of the model group. AMI rats of CBSS was closely correlated with myocardial metabolites such as malic acid, glutamic acid, glycine, glucose, fumaric acid, urea, galactopyranose, lactic acid, alanine, and tyrosine, etc. CONCLUSIONS: The metabolite profile of rats' myocardial tissue showed AMI rat model of CBSS was closely correlated with post-hypoxia glucose metabolism disorder. YTR could effectively intervene this process.

[Mesenchymal stem cells implantation increases the myofibroblasts congregating in infarct region in a rat model of myocardial infarction].

OBJECTIVE: To investigate the modulation effects of mesenchymal stem cells (MSC) implantation on the myofibroblasts congregating in the infarct region after myocardial infarction (MI). METHODS: MI was induced in SD rats by left anterior descending coronary artery ligation, and the experimental animals were assigned randomly into the sham group, MI + PBS group and MI + MSC group (myocardial injection of 0.1 ml 2×10(7)/ml in four locations in the infarct region). Echocardiography, hemodynamic examinations and Masson trichrome staining were performed. Implanted MSC differentiation and myofibroblasts congregating in infarct region were investigated by immunofluorescence staining. TGF-ß(1)-Smad2 signaling pathway was examined by real-time RT-PCR and Western blot. RESULTS: (1) Four weeks late, heart-weight/body-weight ratio [(3.04 ± 0.16) mg/g vs. (3.34 ± 0.14) mg/g, P < 0.01] and myocardial infarction size [(38.72 ± 2.38)% vs. (46.36 ± 2.81)%, P < 0.01] were significantly reduced in MI + MSC group than in MI + PBS group, while scar thickness of infarct region was thicker [(0.93 ± 0.17) mm vs. (0.65 ± 0.16) mm, P = 0.01], and LVEF was higher [LVEF: (32.5 ± 5.9)% vs. (26.5 ± 4.5)%, P = 0.03] in MI + MSC group than in MI + PBS group. (2) Myofibroblasts congregating in the infarct region was significantly enhanced in MI + MSC group compared with MI + PBS group [(196 ± 20) cells/mm(2) vs. (89 ± 25) cells/mm(2), P < 0.01], and part of implanted MSC expressed α-SMA(+). (3) TGF-ß(1) expression and the phosphorylating of Smad2 in the infarct region were significantly upregulated in MI + MSC group compared with MI + PBS group (all P < 0.05). CONCLUSIONS: MSC could improve myocardial function and promote myofibroblasts congregating in the infarct region via activating the TGF-ß(1)-Smad2 signaling pathway in this model.

Progress in research on gut microbiota in ethnic minorities in China and consideration of intervention strategies based on ethnic medicine: A review.

One of the variables affecting gut microbiota is ethnicity. There are 56 ethnic subgroups in China, and their intestinal flora differs. A wealth of medical resources has also been produced by the presence of numerous ethnic minorities. In this study, we reviewed the pertinent literature on the intestinal flora of ethnic minorities in China and abroad using the CiteSpace visualization software, and we used bibliometric techniques to find the most widely prescribed medications for preventing and treating endemic diseases in ethnic minorities. Based on the gut microbiology of minority populations, we suggest that by comprehensive development involving literature, experimental, and clinical research, the pharmacological action mechanisms for interventions in endemic diseases can be drawn from ethnic medicine. This point of view has not been discussed before and will offer a fresh perspective on the creation and application of ethnic medications as well as a fresh method for the management of prevalent diseases in ethnic communities.

Caridinastellata, a new species of atyid shrimp (Decapoda, Caridea, Atyidae) with the male description of Caridinacavernicola Liang & Zhou, 1993 from Guangxi, China.

Caridinastellata sp. nov. is described from streams in Guangxi, south-western China. The new species clearly belongs to "Caridinaserrata group" of the genus and shows a morphological similarity with C.cantonensis Yu, 1938, C.serrata Stimpson, 1860 and C.pacboDo et al. 2020. Caridinastellata is distinguished from congeners, based on differences in its male first pleopod and appendix masculina morphology, along with COI and 16S rRNA molecular evidence. The first pleopod endopod in male is rectangle, about 0.70 × length of exopod, about 3.7-3.9 × as long as proximally wide, inner margin concave, bearing nearly equal spine setae, outer margin bearing nearly equal long and dense spine setae; appendix interna well developed, arising from distal 1/5 of endopod, reaching to end of endopod, with cincinuli distally. The new species displays a unique and brightly coloured pattern and, therefore, can be easily recognised in the field. Liang & Zhou, 1993 described C.cavernicola from the Lenggu Cave, Du'an County, Guangxi. However, the description was based exclusively on two females. We have collected specimens of both sexes near the type locality and describe herein the previously unknown male and present morphological data on females. Data on the habitat, ecology and levels of threat of the two species are provided and suggest that they should be categorised as vulnerable (VU) under the current IUCN Criteria.

[Dural modulation effects of mesenchymal stem cells implantation on myocardial collagen remodeling in a rat model of myocardial infarction].

OBJECTIVE: To investigate the modulation effects of mesenchymal stem cells (MSCs) implantation on the collagen remodeling in myocardial infarction. METHODS: Acute myocardial infarction (AMI) was induced in SD rats by left anterior descending coronary artery ligation, and the animals were assigned randomly into the Sham group, MI + PBS group and MI + MSCs group. Echocardiography and hemodynamic examinations were performed to evaluate the cardiac function. HE staining and Masson trichrome staining were used to evaluate the myocardial infarction size. Infarcted area and infarcted expansion index were calculated. The expression of collagens in infarcted hearts was evaluated by immunohistochemistry, RT-PCR and Western blot. RESULTS: (1) Infarct area was significantly reduced post MSCs transplantation [MI + MSCs vs. MI + PBS: (38.27 ± 2.70)% vs. (46.20 ± 3.17)%, P < 0.001]. (2) Cardiac function was significantly improved post MSCs transplantation [MI + MSCs vs. MI + PBS: FS(%): 29.98 ± 4.50 vs. 23.43 ± 3.34, P = 0.005; LVSP (mm Hg, 1 mm Hg = 0.133 kPa): 113.63 ± 10.81 vs. 99.25 ± 16.76, P < 0.05; LVEDP (mm Hg): 12.10 ± 4.28 vs. 20.08 ± 4.26, P < 0.05; +dp/dtmax (mm Hg/s): 4616.63 ± 363.34 vs. 3912.75 ± 248.79, P < 0.05; -dp/dtmax (mm Hg/s): 4254.63 ± 324.34 vs. 3530.88 ± 309.71, P < 0.05]. (3) Collagen synthesis was enhanced in infarcted area and decreased in non-infarcted area post MSCs transplantation (P < 0.05). CONCLUSIONS: MSCs transplantation could enhance the collagen synthesis in infarcted area while decrease the deposition of collagen in non-infarcted area in this MI model. This may be one of the mechanisms by which ventricular remodeling is attenuated post MSCs transplantation.

Integrative taxonomy uncovers a new stygobiotic Caridina species (Decapoda, Caridea, Atyidae) from Guizhou Province, China.

Collecting much-needed information on the taxonomy, distribution, and ecology of cave-dwelling shrimp is vital for addressing the urgent challenges in conservation biodiversity in fragile cave ecosystems. Caridina incolor sp. nov., a new atyid shrimp from an underground stream of Yaoshui Cave, Daqikong scenic area, Libo County, Guizhou Province, southwestern China is described based on morphology and DNA analysis (mitochondrial COI). Caridina incolor sp. nov. differs from epigean congeners by its smaller eyes which range from reduced to completely blind; colorless body and appendages; long stylocerite and sixth abdominal segment; and relatively large eggs. In comparison to other cave species, Caridina incolor sp. nov. presents a long rostrum and stylocerite; slender sixth abdominal segment; and unique shape of the appendix masculina. Data on the habitat, ecology, and levels of threat are provided and suggest that it should be categorized as Critically Endangered (CR) under the current IUCN criteria.

Effect of Ag alloying and trace precipitation on corrosion resistance of Ti-Ta-Ag ternary alloy.

This work systematically analysed the electrochemical and corrosion behaviour of Ti-Ta-Ag ternary alloy samples in Hank's solution. For the samples with 1.5% and 3% Ag content, the sintering temperature increased from 750 to 950°C, and the corresponding corrosion resistance increased by 100 times due to the increased alloying of Ag; meanwhile for the sample with 4.5% Ag content, the sintering temperature increased from 750 to 950°C, and the corresponding corrosion resistance decreased by six times due to the increased precipitation of Ag. These tests prove that the Ag alloying is beneficial to the enhancement of the corrosion resistance of Ti-Ta-Ag ternary alloy, but the Ag trace precipitation has the opposite effect. A series of electrochemical characterizations and density functional theory calculations explain the mechanism of the above phenomenon. Ag alloying can promote the formation of uniform, complete, dense, stable and thick passivation layer on the surface of Ti-Ta-Ag ternary alloy, which makes Ti-Ta-Ag ternary alloy uniformly corroded without pitting. In addition, Ag alloying can effectively reduce the contact resistance of the solid-liquid interface. However, the trace precipitation of Ag plays the opposite role to the above effect.

Observing time effect of SSRIs on suicide risk and suicide-related behaviour: a network meta-analysis protocol.

INTRODUCTION: Suicide is a serious problem worldwide and 90% cases are associated with pre-existing or underlying mental illness. As a common treatment for depressive symptoms that suicidal people may receive, selective serotonin reuptake inhibitors (SSRIs) have been linked to a possible increase in suicide rates. Studies focusing on SSRIs and suicide have produced inconsistent results, suggesting that use of SSRIs decreases, increases, has no effect on suicide rates, or that the effect of SSRIs on suicide is age-dependent. This protocol of network meta-analysis aims to precisely evaluate the time effects of SSRIs by observing weekly changes of suicidality in the first 2 months of the treatment, and consequently, to explore whether the effect of the SSRIs on suicide varies depending on the stages of the treatment; if so, we will identify the turning point. METHODS AND ANALYSIS: We will search in the following databases: PubMed, Web of science, China National Knowledge Infrastructure and Wanfang Data, from dates of inception to 9 July 2021, with language restricted to English and Chinese. Studies focusing on the time effect of SSRIs on suicide will be retrieved. Then, the study selection process will follow the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guideline, and the quality assessment will be conducted with Cochrane Collaboration's tool. Two researchers will work independently on data extraction using a standardised data extraction spreadsheet. Any disagreement between two researchers will be discussed and determined by a third researcher. ETHICS AND DISSEMINATION: This work does not require ethics approval as it will be based on published studies. This review will be published in peer-reviewed journals. PROSPERO REGISTRATION NUMBER: CRD42021244779.

Study of Ag precipitation and mechanical properties of Ti-Ta-Ag ternary alloy.

Ti-25Ta-xAg alloy samples with different content of Ag were prepared by spark plasma sintering method. X-ray diffraction, microscopic metallographic, scanning electron microscopy, and transmission electron microscopy were used to analyze the phase structure and morphology of the alloy samples. Ti-Ta-Ag can form a stable ternary alloy system. Furthermore, with the increase of Ag content and sintering temperature, Ag will be precipitated at the grain boundary. In order to explore the precipitation mechanism of Ag in the alloy and its influence on the mechanical properties, the crystal structure, electronic structure, and elastic constant under different Ag solid solubility were calculated systematically by using first-principles calculations. The results show that the critical temperature of Ag in Ti-Ta-Ag ternary alloy is about 2200 K, and the high temperature is favorable for the aging precipitation of Ag. The lattice constants and mechanical properties of (Ti1-x Ag x )3Ta solid solution suddenly change when the Ag solid solubility x value is equal to 0.8, and their changes will follow different rules. The internal mechanism of this phenomenon is that the 4d10 electronic states of Ag have changed from obvious local electronic states to mixed local and non-local electronic states. These results provide theoretical guidance for the application of Ti-Ta-Ag ternary alloys in biomedicine.

Two freshwater shrimp species of the genus Caridina (Decapoda, Caridea, Atyidae) from Dawanshan Island, Guangdong, China, with the description of a new species.

A faunistic and ecological survey was conducted to document the diversity of freshwater atyid shrimps of Dawanshan Island. Two species of Caridina that occur on this island were documented and discussed. One of these, Caridina tetrazona sp. nov. is described and illustrated as new to science. It can be easily distinguished from its congeners based on a combination of characters, which includes a short rostrum, the shape of the endopod of the male first pleopod, the segmental ratios of antennular peduncle and third maxilliped, the slender scaphocerite, and the absence of a median projection on the posterior margin. Live individuals of the new species display a unique coloration pattern with four dark blue transverse bands on the body, and can be easily recognized in the field. So far, despite considerable surveying efforts made on neighboring islands, this species has only been found from a small stream on Dawanshan Island, which suggests that it may have a very limited range, probably endemic to Dawanshan Island. Molecular characteristics of the mitochondrial cytochrome c oxidase subunit I (COI) demonstrate that this species shows sufficient interspecific divergence from its congeners, including C. serrata Stimpson, 1860, which was found in four streams on Dawanshan Island, and has been previously reported on the neighboring islands of Hong Kong, Dong'ao, Wailingding, and Guishan.

Macrobrachium tenuipes, a new stygophile freshwater prawn specie (Crustacea: Caridea: Palaemonidae) from a karst cave of Guangxi, southwestern China.

Based on morphological, molecular, and ecological evidences, a fourth species of cave-dwelling shrimp Macrobrachium tenuipes sp. nov. is described from Guangxi Zhuang Autonomous Region, southwestern China. This new species with smooth carapace and the extremely slender pereiopods, can be separated from other congeners by the shape of rostrum; the segmental ratios, the arrangement of teeth on the cutting edge of the fingers of second pereiopod; the longer and narrower scaphocerite; and the longer uropodal diaeresis spine. The new taxon is genetically distinct from 18 other species of Macrobrachium for which COI and 18S rRNA sequences are available. The data observed on the habitat and ecology will contribute to the conservation for M. tenuipes sp. nov.