Low-Temperature Sodium-Ion Batteries: Challenges and Progress

As an ideal candidate for the next generation of large-scale energy storage devices, sodium-ion batteries (SIBs) have received great attention due to their low cost. However, the practical utility of SIBs faces constraints imposed by geographical and environmental factors, particularly in high-altitude and cold regions. In these areas, the low-temperature (LT) performance of SIBs presents a pressing technological challenge that requires significant breakthroughs. In LT environments, the electrochemical reaction kinetics of SIBs are sluggish, the electrode/electrolyte interface is unstable, and the diffusion of sodium ions in electrode materials is slow, leading to a decrease in battery performance. Therefore, the reasonable design of electrolyte and electrode materials is of great significance for optimizing the LT performance of SIBs. In this review, the research progress of LT SIBs electrolytes, cathode, and anode materials, as well as sodium metal batteries and solid-state electrolytes is systematically summarized in recent years, aiming to understand the design principles of LT SIBs, clarify the basic research and development of high-performance SIBs in practical applications, and promote the development of SIBs technology in the full temperature range.     

Sampling and energy evaluation challenges in ligand binding protein design

The steroid hormone 17α‐hydroxylprogesterone (17‐OHP) is a biomarker for congenital adrenal hyperplasia and hence there is considerable interest in development of sensors for this compound. We used computational protein design to generate protein models with binding sites for 17‐OHP containing an extended, nonpolar, shape‐complementary binding pocket for the four‐ring core of the compound, and hydrogen bonding residues at the base of the pocket to interact with carbonyl and hydroxyl groups at the more polar end of the ligand. Eight of 16 designed proteins experimentally tested bind 17‐OHP with micromolar affinity. A co‐crystal structure of one of the designs revealed that 17‐OHP is rotated 180° around a pseudo‐two‐fold axis in the compound and displays multiple binding modes within the pocket, while still interacting with all of the designed residues in the engineered site. Subsequent rounds of mutagenesis and binding selection improved the ligand affinity to nanomolar range, while appearing to constrain the ligand to a single bound conformation that maintains the same “flipped” orientation relative to the original design. We trace the discrepancy in the design calculations to two sources: first, a failure to model subtle backbone changes which alter the distribution of sidechain rotameric states and second, an underestimation of the energetic cost of desolvating the carbonyl and hydroxyl groups of the ligand. The difference between design model and crystal structure thus arises from both sampling limitations and energy function inaccuracies that are exacerbated by the near two‐fold symmetry of the molecule.     

The ultimate and proximate mechanisms driving the evolution of long tails in forest deer mice

Understanding both the role of selection in driving phenotypic change and its underlying genetic basis remain major challenges in evolutionary biology. Here, we use modern tools to revisit a classic system of local adaptation in the North American deer mouse, Peromyscus maniculatus, which occupies two main habitat types: prairie and forest. Using historical collections, we find that forest‐dwelling mice have longer tails than those from nonforested habitat, even when we account for individual and population relatedness. Using genome‐wide SNP data, we show that mice from forested habitats in the eastern and western parts of their range form separate clades, suggesting that increased tail length evolved independently. We find that forest mice in the east and west have both more and longer caudal vertebrae, but not trunk vertebrae, than nearby prairie forms. By intercrossing prairie and forest mice, we show that the number and length of caudal vertebrae are not correlated in this recombinant population, indicating that variation in these traits is controlled by separate genetic loci. Together, these results demonstrate convergent evolution of the long‐tailed forest phenotype through two distinct genetic mechanisms, affecting number and length of vertebrae, and suggest that these morphological changes—either independently or together—are adaptive.     

Staphylococcal protein A promotes osteoclastogenesis through MAPK signaling during bone infection

Bone infection is a common and serious complication in the orthopedics field, which often leads to excessive bone destruction and non‐union. Osteoclast is the only type of cells which have the function of bone resorption. Its over activation is closely related to excessive bone loss. Staphylococcus aureus (S. aureus) is a major pathogen causing bone infection, which can produce a large number of strong pathogenic substances staphylococcal protein A (SPA). However, few studies were reported about the effects of SPA on osteoclastogenesis. In our study, we observed that S. aureus activated osteoclasts and promoted bone loss in bone infection specimens. Then, we investigated the effects of SPA on RANKL‐induced osteoclastogenesis in vitro, the results revealed that SPA promoted osteoclastic differentiation and fusion, and enhanced osteoclastic bone resorption. In addition, we also showed that SPA upregulated the expression of NFATc1 and c‐FOS through the activation of MAPK signaling to promote osteoclastogenesis. Our findings might help us better understand the pathogenic role of S. aureus in bone infection and develop new therapeutic strategies for infectious bone diseases.     

Three‐Stage Inter‐Orthorhombic Evolution and High Thermoelectric Performance in Ag‐Doped Nanolaminar SnSe Polycrystals

The ultrahigh thermoelectric performance of SnSe‐based single crystals has attracted considerable interest in their polycrystalline counterparts. However, the temperature‐dependent structural transition in SnSe‐based thermoelectric materials and its relationship with their thermoelectric performance are not fully investigated and understood. In this work, nanolaminar SnSe polycrystals are prepared and characterized in situ using neutron and synchrotron powder diffraction measurements at various temperatures. Rietveld refinement results indicate that there is a complete inter‐orthorhombic evolution from Pnma to Cmcm by a series of layer slips and stretches along the a‐ and b‐axes over a 200 K temperature range. This phase transition leads to drastic enhancement of the carrier concentration and phonon scattering above 600 K. Moreover, the unique nanolaminar structure effectively enhances the carrier mobility of SnSe. Their grain and layer boundaries further improve the phonon scattering. These favorable factors result in a high ZT of 1.0 at 773 K for pristine SnSe polycrystals. The thermoelectric performances of polycrystalline SnSe are further improved by p‐type and n‐type dopants (i.e., doped with Ag and SnCl₂, respectively), and new records of ZT are achieved in Ag_0.015Sn_0.985Se (ZT of 1.3 at 773 K) and SnSe_0.985Cl_0.015 (ZT of 1.1 at 773 K) polycrystals.     

吉林珲春自然保护区东北虎和东北豹及其有蹄类猎物的多度与分布

珲春国家级自然保护区是东北虎(Panthera tigris altaica)、东北豹(Panthera pardus orientalis)等濒危物种在中国的核心分布区。为了探究该区域野生动物的多度水平和空间分布, 了解人类干扰情况, 我们运用相对多度指数(relative abundance index, RAI)分析了2013年4-6月设置于此的83个红外相机位点的监测数据。红外相机的总捕获天数6,060 d, 共捕获10科18种野生哺乳动物, 其中鼬科4种, 猫科动物3种, 犬科、鹿科和松鼠科各2种, 猪科、熊科、麝科、猬科和兔科各1种。研究期间共拍摄到东北虎11只个体, 东北豹13只个体。从相对多度指数来看, 东北虎的相对多度(0.84)远高于东北豹(0.48), 它们的有蹄类猎物中梅花鹿(Cervus nippon)的相对多度最高(2.18), 其次为狍(Capreolus pygargus)(1.53)和野猪(Sus scrofa)(0.92)。人类活动和放牧的相对多度水平(分别为40.64和2.76)显著高于野生动物。在空间分布上, 东北虎和梅花鹿主要在保护区的核心区分布, 且与保护区社区共管区的多度水平差异显著, 而东北豹在不同功能区之间的分布差异不显著, 狍在保护区北部的多度水平较高, 但各功能区之间差异不显著, 野猪在社区共管区的多度水平显著高于核心区。可见, 核心区频繁的人类活动和放牧活动对野生动物的保护产生了影响, 未来应加强关于人类干扰对虎、豹种群及其有蹄类猎物的影响评估。     

Acetaminophen: antipyretic or hypothermic in mice? In either case, PGHS-1b (COX-3) is irrelevant

Acetaminophen (AC) reduces the core temperatures (T(c)) of febrile and non-febrile mice alike. Evidence has been adduced that the selectively AC-sensitive PGHS isoform, PGHS-1b (COX-3), mediates these effects. PGHS-1b, however, has no catalytic potency in mice. To resolve this contradiction, AC was injected intravenously (i.v.) into conscious PGHS-1 gene-sufficient (wild-type (WT)) and -deficient (PGHS-1(-/-)) mice 60 min before or after pyrogen-free saline (PFS) or E. coli LPS (10 microg/kg) i.v. T(c) was monitored continuously; brain and plasma PGE(2) levels were determined hourly. AC at <160 mg/kg did not affect T(c) when given before PFS or LPS; at 160 mg/kg, it caused a approximately 2.5 degrees C T(c) fall in 60 min. LPS given after AC (all doses) induced a approximately 1 degrees C fever, not different from that in AC-untreated mice. But this rise was insufficient to overcome the hypothermia of the 160 mg/kg-treated mice; their T(c) culminated 1 degrees C below baseline. LPS given before AC similarly elevated T(c) approximately 1 degrees C. This rise was reduced to baseline in 30 min by 80 mg AC/kg; T(c) rebounded to its febrile level over the next 30 min. At 160 mg/kg, AC reduced T(c) to 4 degrees C below baseline in 60 min, where it remained until the end of the experiment. WT and PGHS-1(-/-) mice responded similarly to all the treatments. The basal brain and plasma PGE(2) levels of PFS mice and the elevated plasma levels of LPS mice were unchanged by AC at 160 mg/kg; but the latter's brain levels were reduced at 1h, then recovered. Thus, AC could exert an anti-PGHS-2 effect when this enzyme is upregulated in the brain of febrile mice. The hypothermia it induces in non-febrile mice, therefore, is due to another mechanism. PGHS-1b is not involved in either case.