Enhanced Hydrogen Evolution Catalysis of Pentlandite due to the Increases in Coordination Number and Sulfur Vacancy during Cubic-Hexagonal Phase Transition.

The search for new phases is an important direction in materials science. The phase transition of sulfides results in significant changes in catalytic performance, such as MoS2 and WS2 . Cubic pentlandite [cPn, (Fe, Ni)9 S8 ] can be a functional material in batteries, solar cells, and catalytic fields. However, no report about the material properties of other phases of pentlandite exists. In this study, the unit-cell parameters of a new phase of pentlandite, sulfur-vacancy enriched hexagonal pentlandite (hPn), and the phase boundary between cPn and hPn are determined for the first time. Compared to cPn, the hPn shows a high coordination number, more sulfur vacancies, and high conductivity, which result in significantly higher hydrogen evolution performance of hPn than that of cPn and make the non-nano rock catalyst hPn superior to other most known nanosulfide catalysts. The increase of sulfur vacancies during phase transition provides a new approach to designing functional materials.

Relationship of individual and mixed urinary metals exposure with liver function in the China National Human Biomonitoring (CNHBM) of Zhejiang Province.

BACKGROUND: Heavy metals have been reported to affect liver function. However, there is currently little and inconsistent knowledge about the effects of combined and individual urinary metals on specific parameters of liver function in the general population. Therefore, this study aimed to investigate their associations. METHODS: This study involved 807 general population from the China National Human Biomonitoring of Zhejiang Province 2017-2018. Concentrations of urinary metals, including Chromium (Cr), Cobalt (Co), Nickle (Ni), Arsenic (As), Selenium (Se), Molybdenum (Mo), Cadmium (Cd), Thallium (Tl) and Lead (Pb) were measured. Alanine aminotransferase (ALT), aspartate aminotransferase (AST), total protein (TP), albumin (ALB), direct bilirubin (DBIL), total bilirubin (TBIL) as liver function biomarkers. Multivariable linear regression and weighted quantile sum (WQS) regression were employed to explore the associations of urinary metals with liver function biomarkers. Subgroup analysis stratified by gender and age, excluding smokers and drinkers for sensitivity analysis. RESULTS: Both statistical models indicated that urinary metals were positively associated with ALT and AST, while negatively with TP, ALB, DBIL and TBIL. In the WQS analysis, each quartile increase in the ln-transformed levels of metal mixtures was associated with 4.11 IU/L (95% CI: 1.07, 7.15) higher ALT and 3.00 IU/L (95% CI: 1.75, 4.25) higher AST, as well as, with 0.67 g/L (95% CI: 1.24, -0.11) lower TP, 0.74 g/L (95% CI: 1.09, -0.39) lower ALB, 0.38 µmol/L (95% CI: 0.67, -0.09) lower DBIL, and 1.56 µmol/L (95% CI: 2.22, -0.90) lower TBIL. The association between urinary metals and ALT was primarily driven by Cd (55.8%), Cr contributed the most to the association with AST (20.2%) and TBIL (45.2%), while the association with TP was primarily driven by Ni (38.2%), the association with ALB was primarily driven by As (32.8%), and the association with DBIL was primarily driven by Pb (30.9%). The associations between urinary metals and liver function might differ by sex and age. CONCLUSION: Urinary metals were significantly associated with liver function parameters. Further studies are required to clarify the relationship between heavy metals and liver function.

Oldhamite: a new link in upper mantle for C-O-S-Ca cycles and an indicator for planetary habitability.

In the solar system, oldhamite (CaS) is generally considered to be formed by the condensation of solar nebula gas. Enstatite chondrites, one of the most important repositories of oldhamite, are believed to be representative of the material that formed Earth. Thus, the formation mechanism and the evolution process of oldhamite are of great significance to the deep understanding of the solar nebula, meteorites, the origin of Earth, and the C-O-S-Ca cycles of Earth. Until now, oldhamite has not been reported to occur in mantle rock. However, here we show the formation of oldhamite through the reaction between sulfide-bearing orthopyroxenite and molten CaCO3 at 1.5 GPa/1510 K, 0.5 GPa/1320 K, and 0.3 GPa/1273 K. Importantly, this reaction occurs at oxygen fugacities within the range of upper-mantle conditions, six orders of magnitude higher than that of the solar nebula mechanism. Oldhamite is easily oxidized to CaSO4 or hydrolysed to produce calcium hydroxide. Low oxygen fugacity of magma, extremely low oxygen content of the atmosphere, and the lack of a large amount of liquid water on the celestial body's surface are necessary for the widespread existence of oldhamite on the surface of a celestial body otherwise, anhydrite or gypsum will exist in large quantities. Oldhamites may exist in the upper mantle beneath mid-ocean ridges. Additionally, oldhamites may have been a contributing factor to the early Earth's atmospheric hypoxia environment, and the transient existence of oldhamites during the interaction between reducing sulfur-bearing magma and carbonate could have had an impact on the changes in atmospheric composition during the Permian-Triassic Boundary.

Experimental Study on the Tridacna squamosa Shell: Distinctive Structure and Mechanical Behavior.

Tridacna squamosa, Lamarck, 1819 (Bivalvia Cardiida Cardiidae, known as the fluted giant clam) is one of the largest-sized bivalve shells, which is equipped with a strong and tough bioceramic shell to effectively protect itself from the attack of predators. To better understand the mechanical defense mechanism, the relationship between the microstructure, composition, and mechanical properties of the Tridacna squamosa shell was investigated. We find that the Tridacna squamosa shell is composed of aragonite CaCO3 and a small portion of organic matter, which are well-arranged, assembling a multiscale, inhomogeneous, and anisotropic structure. Three levels of microstructure units are identified, including the smallest aragonite rods, medium sheets, and block-like lamellae. Such multiscale structures are the main contributor to creating abundant fracture surfaces much larger than the case for single mineral components, leading to multiple toughening mechanisms observed in Vickers indentation experiments, such as pulled-out of mineral platelet and crack deflection. The material inhomogeneity in the cross-sectional direction indicates that the material is stronger at the inner layer than that at the outer layer, which also facilitates an effective defense against the predator attack. This study may provide insights into the design of biomaterials with the desired mechanical properties.

[Establishment and evaluation of identification method for Yersinia pestis and Yersinia pseudotuberculosis].

OBJECTIVE: To establish a gene identification method of Yersinia pestis and Yersinia pseudotuberculosis for plague surveillance. METHODS: According to the specific genomic sequences of Y. pestis and Y. pseudotuberculosis, i.e. "pestis Island (PeI)" and "pseudotuberculosis Island (PsI)" and the published genomic sequences of 12 strains of Y. pestis and 4 strains of Y. pseudotuberculosis, the specific identification primers of these sequences were designed. RESULTS: A total of 52 strains of Y. pestis and 57 strains of Y. pseudotuberculosis and other intestinal bacteria strains were tested with PCR. Of the 5 pairs of Y. pestis identification primers, PeI2 and PeI11 were specific for Y. pestis. Besides Y. pestis, the primers PeI1, PeI3 and PeI12 could detect part of 57 Y. pseudotuberculosis strains. Of the 5 pairs of Y. pseudotuberculosis identification primers, PsI1 could detect all the 52 strains of Y. pestis and 57 strains of Y. pseudotuberculosis. PsI7, PsI16, PsI18 and PsI19 were specific for Y. pseudotuberculosis. CONCLUSION: The primers PsI1, PeI 2 and PeI11, PsI7, PsI16, PsI18 and PsI19 can be used in the rapid identification of Y. pestis and Y. pseudotuberculosis, which can be also used to explore the circulation of atypical Y. pestis in quiescent plague foci.

Discovery, diversity and evolution of novel coronaviruses sampled from rodents in China.

Although rodents are important reservoirs for RNA viruses, to date only one species of rodent coronavirus (CoV) has been identified. Herein, we describe a new CoV, denoted Lucheng Rn rat coronavirus (LRNV), and novel variants of two Betacoronavirus species termed Longquan Aa mouse coronavirus (LAMV) and Longquan Rl rat coronavirus (LRLV), that were identified in a survey of 1465 rodents sampled in China during 2011-2013. Phylogenetic analysis revealed that LAMV and LRLV fell into lineage A of the genus Betacoronavirus, which included CoVs discovered in humans and domestic and wild animals. In contrast, LRNV harbored by Rattus norvegicus formed a distinct lineage within the genus Alphacoronavirus in the 3CL(pro), RdRp, and Hel gene trees, but formed a more divergent lineage in the N and S gene trees, indicative of a recombinant origin. Additional recombination events were identified in LRLV. Together, these data suggest that rodents may carry additional unrecognized CoVs.

Ongoing spillover of Hantaan and Gou hantaviruses from rodents is associated with hemorrhagic fever with renal syndrome (HFRS) in China.

BACKGROUND: Longquan City, Zhejiang province, China, has been seriously affected by hemorrhagic fever with renal syndrome (HFRS) since the first cases were registered in 1974. To understand the epidemiology and emergence of HFRS in Longquan, which may be indicative of large parts of rural China, we studied long-term incidence patterns and performed a molecular epidemiological investigation of the causative hantaviruses in human and rodent populations. METHOD/PRINCIPAL FINDINGS: During 1974-2011, 1866 cases of HFRS were recorded in Longquan, including 20 deaths. In 2011, the incidence of HFRS remained high, with 19.61 cases/100,000 population, despite the onset of vaccination in 1997. During 1974-1998, HFRS cases in Longquan occurred mainly in winter, while in the past decade the peak of HFRS has shifted to the spring. Notably, the concurrent prevalence of rodent-borne hantaviruses in the region was also high. Phylogenetic analyses of viral sequences recovered from rodents in Longquan revealed the presence of novel genetic variants of Gou virus (GOUV) in Rattus sp. rats and Hantaan virus (HTNV) in the stripe field mice, respectively. Strikingly, viral sequences sampled from infected humans were very closely related to those from rodents. CONCLUSIONS/SIGNIFICANCE: HFRS represents an important public health problem in Longquan even after years of preventive measures. Our data suggest that continual spillover of the novel genetic variant of GOUV and the new genetic lineage of HTNV are responsible for the high prevalence of HFRS in humans. In addition, this is the first report of GOUV associated with human HFRS cases, and our data suggest that GOUV is now the major cause of HFRS in this region.

[Investigation on the natural infectious status of hantaviruses among small mammals in Longquan city, Zhejiang province].

OBJECTIVE: To investigate the situation of the natural infection of hantaviruses (HV) in small mammals and to provide evidence for the control and prevention of hemorrhagic fever with renal syndrome (HFRS) in Longquan area, Zhejiang province. METHODS: Small mammals were captured by night trap, and lung tissue samples were collected and stored in liquid nitrogen. HV antigens were detected by indirect immuno-fluorescence assay (IFA). The partial S genome segment sequences were amplified by RT-PCR. DNAStar program was used for editing and comparing the sequences. Phylogeny was analyzed through PAUP*4.0 software. RESULTS: 319 small animals were collected in Longquan, and 9 hantavirus antigen-positive samples were identified. The positive rate of hantavirus in Apodemus agrarius was 4.97%. Phylogenetic tree constructed by partial S segment (620 - 999 nt) showed that the 9 strains carried by A. agrarius from Longquan all belonged to HTNV, and had a closer evolutionary relationship with isolate Z251 from Zhejiang province. CONCLUSION: Our results indicated that the main host was A. agrarius and the infection rate of HTNV was high in Longquan area.