crisis and environmental issue. [1] Electrochemical water electrolysis offers a promising and effective strategy to produce high-quality H 2 without carbon emission. [2] However, the sluggish kinetics of hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) has been a huge challenge for water splitting, which has spurred researchers for exploiting high-efficiency electrocatalysts with reduced dynamic overpotentials. [3] AlthoughPt-based materials and Ru/Ir-based oxides are still known as the most efficient catalysts for HER and OER, they suffer from low abundance and high prices, leading to difficulties in the largescale commercial application. [4] In addition, the most obtained electrocatalysts are not capable of possessing both excellent HER and OER performance in a same electrolyte due to incompatibility of activity over different pH ranges. [5] Therefore, constructing non-noble metal bifunctional electrocatalysts with high performance and cost-effectiveness has become a hot spot for efficient overall water splitting.Recently, low-cost nickel chalcogenides, such as NiS, NiS 2 , and Ni 3 S 2 , have attracted enormous attention for electrolytic water splitting. [6] In particular, the Ni 3 S 2 electrocatalyst has been widely researched due to high conductivity and unique structure configuration, while the imprisoned HER/OER activity Rational design and construction of bifunctional electrocatalysts with excellent activity and durability is imperative for water splitting. Herein, a novel topdown strategy to realize a hierarchical branched Mo-doped sulfide/phosphide heterostructure (Mo-Ni 3 S 2 /Ni x P y hollow nanorods), by partially phosphating Mo-Ni 3 S 2 /NF flower clusters, is proposed. Benefitting from the optimized electronic structure configuration, hierarchical branched hollow nanorod structure, and abundant heterogeneous interfaces, the as-obtained multisite Mo-Ni 3 S 2 /Ni x P y /NF electrode has remarkable stability and bifunctional electrocatalytic activity in the hydrogen evolution reaction (HER)/oxygen evolution reaction (OER) in 1 m KOH solutions. It possesses an extremely low overpotential of 238 mV at the current density of 50 mA cm −2 for OER. Importantly, when assembled as anode and cathode simultaneously, it merely requires an ultralow cell voltage of 1.46 V to achieve the current density of 10 mA cm −2 , with excellent durability for over 72 h, outperforming most of the reported Ni-based bifunctional materials. Density functional theory results further confirm that the doped heterostructure can synergistically optimize Gibbs free energies of H and O-containing intermediates (OH*, O*, and OOH*) during HER and OER processes, thus accelerating the catalytic kinetics of electrochemical water splitting. This work demonstrates the importance of the rational combination of metal doping and interface engineering for advanced catalytic materials.The ORCID identification number(s) for the author(s) of this article can be found under https://doi.

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BackgroundPleistocene climate fluctuations have shaped the patterns of genetic diversity observed in many extant species. In montane habitats, species' ranges may have expanded and contracted along an altitudinal gradient in response to environmental fluctuations leading to alternating periods of genetic isolation and connectivity. Because species' responses to climate change are influenced by interactions between species-specific characteristics and local topography, diversification pattern differs between species and locations. The eastern Himalayas is one of the world's most prominent mountain ranges. Its complex topography and environmental heterogeneity present an ideal system in which to study how climatic changes during Pleistocene have influenced species distributions, genetic diversification, and demography. The Elliot's laughing thrush (Garrulax elliotii) is largely restricted to high-elevation shrublands in eastern Himalayas. We used mitochondrial DNA and microsatellites to investigate how genetic diversity in this species was affected by Pleistocene glaciations.ResultsMitochondrial data detected two partially sympatric north-eastern and southern lineages. Microsatellite data, however, identified three distinct lineages congruent with the geographically separated southern, northern and eastern eco-subregions of the eastern Himalayas. Geographic breaks occur in steep mountains and deep valleys of the Kangding-Muli-Baoxin Divide. Divergence time estimates and coalescent simulations indicate that lineage diversification occurred on two different geographic and temporal scales; recent divergence, associated with geographic isolation into individual subregions, and historical divergence, associated with displacement into multiple refugia. Despite long-term isolation, genetic admixture among these subregional populations was observed, indicating historic periods of connectivity. The demographic history of Garrulax elliotii shows continuous population growth since late Pleistocene (about 0.125 mya).ConclusionWhile altitude-associated isolation is typical of many species in other montane regions, our results suggest that eco-subregions in the eastern Himalayas exhibiting island-like characteristics appear to have determined the diversification of Garrulax elliotii. During the Pleistocene, these populations became isolated on subregions during interglacial periods but were connected when these expanded to low altitude during cooler periods. The resultant genetic admixture of lineages might obscure pattern of genetic variation. Our results provide new insights into sky island diversification in a previously unstudied region, and further demonstrate that Pleistocene climatic changes can have profound effects on lineage diversification and demography in montane species.

Developing efficient and durable bifunctional transition metal phosphide (TMP) electrocatalysts is still a great challenge because of its relatively sluggish kinetics of oxygen evolution reaction (OER). Herein, we report a unique bimetallic diphosphide pair (FeP 2 −NiP 2 ) forming spherical nanocages encapsulated in P-doped carbon layers (FeP 2 − NiP 2 @PC) as advanced bifunctional electrocatalyst synthesized by a very facile phosphorization approach. The obtained FeP 2 −NiP 2 @PC electrocatalyst exhibits an outstanding OER activity with an ultralow overpotential of 248 mV in 1 M KOH and a low overpotential of 117 mV for HER in 0.5 M H 2 SO 4 (@10 mA•cm −2 ). Also it gives an exceptional longterm durability toward OER (60 h) and HER (20 h). Differently from the electrocatalysts as reported, after successive 3000 cycles CV acceleration, its overpotential decreases about 10 mV. Further investigation unveils that the electrochemical activation process boosts in situ phase transformation of oxides and phosphides to oxyhydroxides as the vital intermediates in FeP 2 −NiP 2 @PC during OER electrocatalysis. The direct observation of vital intermediates has been rarely reported on Fe/Ni-based phosphide electrocatalysts. Our exploration demonstrates an extraordinarily efficient and stable nonprecious TMP bifunctional electrocatalyst and provides a novel prospect to shed light on the intrinsic OER electrocatalytic behavior of Fe/Ni-based phosphide electrocatalysts.

The rational construction of earth‐abundant and advanced electrocatalysts for oxygen evolution reaction (OER) is extremely desired and significant to seawater electrolysis. Herein, by directly etching Ni3S2 nanosheets through potassium ferricyanide, a novel self‐sacrificing template strategy is proposed to realize the in situ growth of NiFe‐based Prussian blue analogs (NiFe PBA) on Ni3S2 in an interfacial redox reaction. The well‐designed Ni3S2@NiFe PBA composite as precursor displays a unique spherical magic cube architecture composed of nanocubes, which even maintains after a phosphating treatment to obtain the derived Ni3S2/Fe‐NiPx on nickel foam. Specifically, in alkaline seawater, the Ni3S2/Fe‐NiPx as OER precatalyst marvelously realizes the ultralow overpotentials of 336 and 351 mV at large current densities of 500 and 1000 mA cm–2, respectively, with remarkable durability for over 225 h, outperforming most reported advanced OER electrocatalysts. Experimentally, a series of characterization results confirm the reconstruction behavior in the Ni3S2/Fe‐NiPx surface, leading to the in situ formation of Ni(OH)2/Ni(Fe)OOH with abundant oxygen vacancies and grain boundaries, which constructs the Ni3S2/Fe‐NiPx reconstruction system responsible for the remarkable OER catalytic activity. Theoretical calculation results further verify the enhanced OER activity for Ni3S2/Fe‐NiPx reconstruction system, and unveil that the Fe‐Ni2P/FeOOH as active origin contributes to the central OER activity.

Analyzing evolution characteristics of landscape ecological risk patterns would help establish ecological risk early warning mechanism, reduce the ecological risk probability and promote coastal landscape pattern optimization. In this study, landscape pattern indices were first calculated by using multitemporal Landsat TM images acquired in years 1990, 2000 and 2010, then landscape ecological risk pattern evolution models and the spatiotemporal evolutions of ecological risk patterns of coastal zones in Zhejiang province, China were constructed and analyzed. The results demonstrate that (1) greater changes have taken place in landscape structures during the two decades, and (2) the areas of cropland, sea, woodland and water surface have decreased significantly, while the areas of built-up land, unused land and aquaculture land have increased. In 1990, coastal landscapes were mainly occupied by extremely low and low ecological risk areas. However, by 2010, the low ecological risk area apparently decreased compared to that in 1990, while extremely high and high ecological risk areas increased significantly, occupying spatial regions where originally the extremely low and low ecological risk zones located. Transition rates of ecological risk grades in the second ten years (2000)(2001)(2002)(2003)(2004)(2005)(2006)(2007)(2008)(2009)(2010) were significantly lower than in the first ten years (1990)(1991)(1992)(1993)(1994)(1995)(1996)(1997)(1998)(1999)(2000). The result suggests that people who originally urged to accelerate coastal landscape exploitation and development have started to concern the ecological environment protection and to pursue a mode that economic development and ecological protection are synchronously conducted.

Genes that are indispensable for survival are essential genes. Many features have been proposed for computational prediction of essential genes. In this paper, the least absolute shrinkage and selection operator method was used to screen key sequence-based features related to gene essentiality. To assess the effects, the selected features were used to predict the essential genes from 31 bacterial species based on a support vector machine classifier. For all 31 bacterial objects (21 Gram-negative objects and ten Gram-positive objects), the features in the three datasets were reduced from 57, 59, and 58, to 40, 37, and 38, respectively, without loss of prediction accuracy. Results showed that some features were redundant for gene essentiality, so could be eliminated from future analyses. The selected features contained more complex (or key) biological information for gene essentiality, and could be of use in related research projects, such as gene prediction, synthetic biology, and drug design.

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