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In distant hybridization of fishes, there is a low hatching rate of hybrid progenies. To further understand the causes of low hatchability, in this article, cross-breeding between zebrafish (ZF) and crucian carp (CC) are generated, in which the hatching rate of cross progenies (ZF♀ × CC♂, ZC) is 35.67%, while that of reciprocal cross progenies (CC♀ × ZF♂, CZ) is about zero. The structures and SDS-PAGE protein pattern of egg envelopes in hybrid early embryos are like their maternal fish, however, during the process of embryo development, some differences are detected between the CZ and CC. The hatching enzyme gene 1 (he1) nucleotide sequences from ZF and CC were 85.1% identity, while that of 99.6% identity was between the ZF and ZC, and 98.4% from CC and hybrid of CZ. There are differences in predictive protein physicochemical properties of he1 between CZ and CC, but no significant change in he1 mRNA levels during embryonic development. Our data furtherly verify that the characteristics of egg envelope and hatching enzyme in hybrid progenies are inherited from maternal fish. Moreover, there are obvious differences between CZ and maternal parent in both egg envelope and hatching enzyme during embryonic development, which are considered to be related to its low hatching rate.

As shining stars of 2-dimensional materials, transition metal carbides (MXene) and transition metal oxides have attracted much interest in various energy fields due to their excellent conductive and electrochemical properties. However, big challenge still remains in the accessibility of high-performance fibrous electrodes for flexible supercapacitors. In this paper, MnO2 nanorods are loaded on MXene sheets to obtain MnO2@MXene composites by a facile hydrothermal method, which are subsequently coated on carbon nanotube fibers (CNTFs). With a fine control on morphology, the resulting MnO2@MXene/CNTF electrode exhibits a high specific capacitance of 181.8 F/g at 1 A/g, a capacitance retention of 91% after 5000 charge-discharge cycles, as well as superb flexibility, i.e., neglected capacitance loss at a bending angle of 180°. The as-fabricated flexible composite fiber opens a new door for transition metal carbides and transition metal oxides with great potential in flexible electronics.

Understanding the transformation of Se during the flue-gas cooling process is important for controlling Se emissions. By analyzing the thermal stability of Se in ash collected from power plant dust collectors, physical migration was found to be the main pathway by which gaseous Se transformed into ash during the flue-gas cooling process. The dynamic curves were obtained for SeO

The effect of applying sandblasting during pretreatment while preparing titanium based IrO 2 − Ta 2 O 5 anodes by the conventional method was investigated. It was observed that sandblasting influences the surface morphology both before and after coating as deeper and smaller etching pits are obtained on the substrate before coating process and rougher surface is obtained after coating. As a result larger outer electrochemical active surface area (ECSA) is obtained on the anodes with sandblasting, which was determined based on cyclic voltammetry, whereas the inner ECSA is independent of the pretreatment. The polarization measurements in a quasi-steady state reveal that sandblasting has slight influence on the catalytic activity. Accelerated lifetime tests were carried out in acidic 0.9 mol L−1 Na2SO4 solution (pH = 2) at a current density of 5 × 107 A cm−2 under galvanostatic conditions. It shows that sandblasting would shorten the lifetime of the anode due to oxidation of the titanium substrate. This is suggested to be due to the shorter distance between the lowest spot of the outer coating surface and the highest spot of the outer substrate of the anode after applying sandblasting in titanium substrate pretreatment.

Previous research has indicated that the small compound, SP600125, could induce polyploidy of fish cells, and has established a stable tetraploid cell line from diploid fish cells. In order to explore how fish cells maintain homeostasis under SP600125-stress in vitro, this study investigates impacts of SP600125-stress on intracellular pathways, as well as on regulation of the cellular homeostasis feedback in fish cells. Transcriptomes are obtained from the SP600125-treated cells. Compared with unigenes expressed in control group (crucial carp fin cells), a total of 2670 and 1846 unigenes are significantly upregulated and downregulated in these cells, respectively. Differentially expressed genes are found, which are involved in innate defense, inflammatory pathways and cell adhesion molecules-related pathways. The SP600125-stress enhances cell-mediated immunity, characterized by significantly increasing expression of multiple immune genes. These enhanced immune genes include the pro-inflammatory cytokines (IL-1β, TNF-ɑ, IL-6R), the adaptor signal transducers (STAT, IκBɑ), and the integrins (ɑ2β1, ɑMβ2). Furthermore, mitochondria are contributed to the cellular homeostasis regulation upon the SP600125-stress. The results show that acute inflammation is an adaptive and controlled response to the SP600125-stress, which is beneficial for alleviating toxicity by SP600125. They provide a potential way of breeding fish polyploidy induced by SP600125 in the future research.

Human granulocytic anaplasmosis (HGA), an increasingly recognized febrile tick-borne illness, is caused by a gram-negative obligate intracellular bacterium Anaplasma phagocytophilum. Because of nonspecific clinical manifestations, diagnosis of HGA highly depends on laboratory tests. Identification of immunoreactive proteins is prerequisite for development of specific and sensitive immunoassays for HGA. In this study, we identified novel immunoreactive proteins of A. phagocytophilum. Previous studies indicated that secreted proteins of A. phagocytophilum and other bacteria can be immunoreactive antigens. Here we in silico screened A. phagocytophilum genome for encoding proteins which bear features of type IV secretion system substrates. Among seventy seven predicted proteins, fourteen proteins were determined for antigenicity and nine proteins were showed to be immunoreactive antigens. In addition, an APH1384 peptide harboring a B cell epitope predicted by bioinformatics was found specifically reacting with anti-A. phagocytophilum sera. Hereby, we identified novel immunoreactive proteins and delineated a specific epitope of A. phagocytophilum, which might be employed for HGA diagnosis.

Three dimensional (3D) extrusion-based printing is a paste-based rapid prototyping process, which is capable of building complex 3D structures. The aim of this study was to explore the feasibility of 3D extrusion-based printing as a pharmaceutical manufacture technique for the fabrication of gastro-floating tablets. Novel low-density lattice internal structure gastro-floating tablets of dipyridamole were developed to prolong the gastric residence time in order to improve drug release rate and consequently, improve bioavailability and therapeutic efficacy. Excipients commonly employed in the pharmaceutical study could be efficiently applied in the room temperature 3D extrusion-based printing process. The tablets were designed with three kinds of infill percentage and prepared by hydroxypropyl methylcellulose (HPMC K4M) and hydroxypropyl methylcellulose (HPMC E15) as hydrophilic matrices and microcrystalline cellulose (MCC PH101) as extrusion molding agent. In vitro evaluation of the 3D printed gastro-floating tablets was performed by determining mechanical properties, content uniformity, and weight variation. Furthermore, re-floating ability, floating duration time, and drug release behavior were also evaluated. Dissolution profiles revealed the relationship between infill percentage and drug release behavior. The results of this study revealed the potential of 3D extrusion-based printing to fabricate gastro-floating tablets with more than 8h floating process with traditional pharmaceutical excipients and lattice internal structure design.

The growth and strain evolution of columnar grains in a Fe-0.5%Mn alloy subjected to hot rolling, cold rolling, and austenite-to-ferrite transformation were studied through electron backscattering diffraction analysis. Because of the formation of the three-layer hot-rolled microstructures with more equal and higher grain orientation spread values (GOSVs), double-layer toothed slender columnar grains with an approximate {100} texture and high GOSVs were obtained. The generation of double-layer toothed coarse columnar grains with a rotated cube texture and higher GOSVs was attributed to the formation of a more inhomogeneous hot-rolled microstructure. Driven by the anisotropic strain energy and surface effect and because of the advantageous austenitic grain size, unique three-layer sandwiched microstructures comprising a surface and under layer of coarse columnar grains with high GOSVs and an inner layer of equiaxed grains with low GOSVs were obtained.

Constrained multiobjective optimization problems (CMOPs) are widespread in real-world applications. Nevertheless, CMOPs with discontinuous feasible regions are challenging for existing evolutionary algorithms due to the difficulty of passing through the infeasible regions. Moreover, there are only several benchmark test problems specified for promoting the research in complex constrained multiobjective optimization. To address these two issues, we first propose a set of CMOPs with discontinuous feasible regions by introducing constraints into the widely used DTLZ test problems, and then a pioneer selection strategy is designed to handle these complex constrained optimization problems. The general idea of the proposed constraint handling strategy is simple, which selects some individuals in the population as the pioneer population, aiming to obtain some well-converged solutions without considering the constraints. By adjusting the ratio of the pioneer solutions during the evaluation, the quasi-optimal solutions are expected to approximate the Pareto optimal front. To investigate the performance of the proposed strategy, it is embedded in a classic evolutionary algorithm and compared with three state-of-the-art constrained multiobjective evolutionary algorithms. Experimental results demonstrate the effectiveness of the proposed strategy and also show that the proposed benchmark problems are challenging for existing approaches.

To compare image quality, radiation, and contrast medium (CM) doses between individualized and conventional scan protocols in combined coronary CT angiography (CCTA) and iliac artery CTA for kidney transplantation patients.148 patients needing assessment for coronary and iliac arteries before kidney transplantation were prospectively enrolled and randomly divided into the conventional and individualized groups. All patients underwent one-stop combined scans on a 256-row CT scanner with automatic tube current modulation, 50 % pre-ASIR-V to control radiation dose. CCTA was performed first using one heartbeat axial scan mode with bolus tracking technique and iliac CTA was performed 3 s after CCTA using a spiral scan. The conventional group (n = 72) used the standard protocol: 100 kVp, 60 mL of 350 mgI/mL CM at 4.5 mL/s flow rate. The individualized group (n = 76) used a body-mass-index (BMI)-dependent protocol: kVp: 80 (BMI 24) and 100 (BMI ≥ 24) and CM: 19 mgI/kg (BMI 18); 21 mgI/kg (18 ≤ BMI 24); and 22 mgI/kg (BMI ≥ 24). Image quality radiation and CM doses of the two groups were compared.There was no significant difference in patient demographic data. Compared with the conventional group, the individualized group reduced contrast flow rate (in mL/s) by 14.4 % (3.85 ± 0.72 vs. 4.5), contrast dose (in mL) by 35.8 % (38.53 ± 7.18 vs. 60) and radiation dose (in mSv) by 34.3 % (4.30 ± 1.73 vs. 6.54 ± 1.45). The individualized group had significantly higher subjective image quality score (P ＜ 0.05), lower noise (17.30 ± 4.97 HU vs. 19.13 ± 4.73 HU, P = 0.02) and higher signal-to-noise ratio (22.09 ± 7.41 vs. 19.55 ± 6.18, P = 0.03) for the three main vessels in CCTA compared with the conventional group. There were no differences in both subjective scores and objective measurements in iliac artery CTA between the two groups.The individualized scanning protocol in the one-stop assessment of coronary and iliac arteries before kidney transplantation significantly reduces both radiation and CM doses while maintaining image quality in iliac artery CTA and providing better coronary artery images in CCTA.

Climate warming is increasing the risks of extinction for many species. Giant panda is one of the most vulnerable mammals to climate warming due to its small population size and specialized diet of bamboo. Many studies have quantified projected habitat loss based on climate-change scenarios, but few have employed empirical data to investigate how the thermal habitat of giant panda has changed. In this study, we investigated the frequency, duration, and intensity of potential heat stress (PHS) occurrence that could surpass the biological threshold of giant panda by analyzing daily temperatures throughout the distribution range of giant panda from 1960 to 2010 and giant panda population survey data. We found an increase in the frequency of PHS25 (PHS above threshold of 25 °C) occurrence at a rate of 1.1–5.5 days/decade. The start date of PHS25 occurrence advanced at a rate of − 1.2 to − 4.6 days/decade, while the end date of PHS25 occurrence was delayed at a rate of 0.8–3.0 days/decade. The giant panda habitat is being exposed to an increased PHS occurrence. The area within reserves and densely populated giant panda habitat exposed to PHS occurrence expanded by 32–317% and 38–218%, respectively from the 1960s to the 2000s. Furthermore, PHS occurrence is intensifying; the annual accumulated degree-days of PHS25 and PHS30 occurrence (PHS above threshold of 30 °C) within the reserves increased by 39% and 140%, respectively. These results confirm that the potential threats to giant panda from climate warming are intensifying. It is urgent to expand the extent and range of giant panda habitat to allow giant pandas to move across landscapes in the face of ongoing climate warming.

The changing of the microstructure and properties with the pre-deformation degree of the 2219 aluminum alloys during aging treatment was investigated. The results reveal that the pre-deformation leads to the increasing of the dislocation density in the matrix that in turn gives rise to the formation of the dense and smaller precipitated θ′ phases with dispersive distribution in the α-matrix, which results in the enhancing of the strength of the pre-deformed samples. It is also observed that the strength of the 4.19% pre-deformed sample shows an abrupt slightly decline by comparing with the 2.88% pre-deformed sample, which caused by the formation of the non-uniformly distributed θ′ precipitates due to the large amount of the dislocation cells formed by the pre-deformation in the matrix.

Summary Leydig cells (LCs) play crucial roles in producing testosterone, and their dysfunction leads to male hypogonadism. LC transplantation is a promising alternative therapy for male hypogonadism. However, the source of LCs limits this strategy for clinical applications. Here, we report our success in reprogramming mice fibroblasts into LCs by expressing three transcriptional factors, Dmrt1, Gata4, and Nr5a1. The induced Leydig-like cells (iLCs) expressed steroidogenic genes, had a global gene expression profile similar to that of adult LCs, and acquired androgen synthesis capabilities. When iLCs were transplanted into rats or mice testes that were selectively depleted of endogenous LCs, the transplanted cells could survive and function in the interstitium of testis, resulting in the restoration of normal levels of serum testosterone. These findings demonstrate that the fibroblasts were able to be directly converted into iLCs by few defined factors, which may facilitate future applications in regenerative medicine., Graphical Abstract, Highlights • Direct reprogramming of fibroblasts into Leydig cell fate by defined factors • Induced Leydig-like cells (iLCs) exhibit adult Leydig cell characterizations • Conversion process toward iLCs did not pass through a mitotic cell state • Transplantation of iLCs could survive and function in the interstitium of testis, In this article, Huang, Su, and colleagues show that a cocktail of transcriptional factors can drive direct lineage reprogramming of mouse fibroblasts into functional Leydig cells (iLCs) which exhibit adult Leydig cell characterizations and acquired androgen synthesis capabilities. Furthermore, iLCs could restore testosterone levels of testosterone-deficient rodents when transplanted into rats or mice testes.

Aeromonas hydrophila (A. hydrophila) is a gram-negative opportunistic pathogen widely distributed in the aquatic environment, which can infect humans, birds, amphibians, reptiles, and fishes. However, the interaction between A. hydrophila and host cells has not been well characterized. In the present study, we investigated the role of autophagy in grass carp (Ctenopharyngodon idella) monocytes/macrophages following infection with A. hydrophila. Our results found that A. hydrophila challenge significantly induced autophagy, as shown by the increase of microtubule-associated protein 1 light chain 3 Ⅱ (LC3 Ⅱ) proteins and LC3 puncta in the cells. Moreover, by using confocal microscopy, the A. hydrophila-elicited autophagy was further confirmed by the colocalization of the A. hydrophila with LC3-positive autophagosome in the cells. In return, the effect of the activated autophagy on the survival of A. hydrophila was examined in the same cell model, showing that rapamycin-induced autophagy was effective in restricting the survival of A. hydrophila. In contrast, autophagy blocked by 3-methyladenine (3-MA) enhanced the amount of A. hydrophila in the cells. All these findings for the first time revealed the role of autophagy in the process of A. hydrophila invading fish immune cells.

Crossover is a crucial operation for generating promising offspring solutions in evolutionary multi-objective optimization. Among various crossover operators, the simulated binary crossover (SBX) is the most widely used in evolutionary multi-objective optimization. Despite that SBX is effective in solving problems with regular Pareto sets, its performance degenerates dramatically on problems with rotated Pareto sets.To address this issue, we propose a modified SBX, named the rotation-based simulated binary crossover (RSBX), to improve the performance of multi-objective evolutionary algorithms (MOEAs) on rotated problems whose Pareto sets are not parallel with the decision variables. The main idea is to introduce the rotation property into the SBX, and then an adaptive selection strategy is proposed to make use of both SBX and RSBX. The proposed method is embedded in three representative MOEAs, and they are compared with their original versions on some problems with rotated Pareto sets, respectively. Experimental results demonstrate that the proposed method is efficient in promoting the performance of conventional MOEAs for handling rotated multi-objective optimization problems.

MnO/carbon nanofiber (CNF) composite is demonstrated as a high-performance electrode material for supercapacitors. LiMn2O4 (LMO) nanoparticle-decorated polyacrylonitrile (PAN) nanofibers are fabricated via electrospinning. Afterwards, LMO is converted to MnO and PAN is fully carbonized under synergistic annealing, resulting in MnO/CNF composite. The composite exhibits electrochemically active in an extended potential window of -1.0 – 0.8 V vs. Ag/AgCl. Moreover, a two-step electrochemical stimulation is observed for MnO at 0.0 V and 0.4 V corresponding to the phase transformations from MnO to Mn3O4 and from Mn3O4 to MnO2, respectively. As a result, the composite presents a high capacitance of 409.7 F g−1 at 1 A g−1 in -0.4 – 0.8 V vs. Ag/AgCl due to the phase transformations of MnO. Also, the composite owns 301.8 F g−1 at 1 A g−1 in -1.0 – 0.2 V vs. Ag/AgCl, which is 2.65 times the value of CNFs owing to the enhanced conductivity and surface redox by incorporating MnO. Finally, a supercapacitor with a working voltage of 1.8 V is realized using MnO/CNF composite as both negative and positive electrodes.

Summary Quantification of stemflow is necessary for the assessment of forest ecosystem hydrological effects. Nevertheless, variation of stemflow among plant functional groups is currently not well understood. Stemflow production of co-occurring evergreen broadleaved trees (Cyclobalanopsis multinervis and Cyclobalanopsis oxyodon) and deciduous broadleaved trees (Fagus engleriana and Quercus serrata var. brevipetiolata) was quantified through field observations in a mixed evergreen and deciduous broadleaved forest. The research results revealed that stemflow increased linearly with increasing rainfall magnitude, with precipitation depths of 6.9, 7.2, 10.0 and 14.8 mm required for the initiation of stemflow for C. multinervis, C. oxyodon, F. engleriana and Q. serrata, respectively. Stemflow percentage and funneling ratio (FR) increased with increasing rainfall in a logarithmic fashion. Stemflow percentage and FR tended to grow rapidly with increasing rainfall magnitude up to a rainfall threshold of 50 mm, above which, further rainfall increases brought about only small increases. For C. multinervis, C. oxyodon, F. engleriana and Q. serrata, FR averaged 19.8, 14.8, 8.9 and 2.8, respectively. The stemflow generating rainfall thresholds for evergreen species were smaller than for deciduous species. Furthermore, stemflow percentage and FR of the former was greater than the latter. For both evergreen species and deciduous species, overall funneling ratio (FRs) decreased with increasing basal area. We concluded that: (1) although stemflow partitioning represented a fairly low percentage of gross rainfall in mixed evergreen and deciduous broadleaved forests, it was capable of providing substantial amount of rainwater to tree boles; (2) the evergreen species were more likely to generate stemflow than deciduous species, and directed more intercepted rainwater to the root zone; (3) small trees were more productive in funneling stemflow than larger trees, which may provide a favorable condition for the survival and growth of small trees when competing with larger trees.

The size-dependent brittle-to-ductile transition of silicon has been observed with nanowire structures in experiments and many research efforts have focused on revealing its underlying physical mechanisms through both experimental and simulation approaches. While most simulation studies using molecular dynamics have considered the influence of various factors such as strain rate, temperature, and size, etc., little is known about the effect of boundary conditions and simulation types, i.e. constant energy vs. constant temperature simulations. In this work, we study the effects of boundary conditions and thermostats on the failure behavior of silicon nanowires by performing the molecular dynamics simulation of the uniaxial tensile test with three modified embedded-atom-method potentials. The nanowires are subjected to either periodic boundary conditions or fixed-end boundary conditions and the simulation is conducted under either the constant energy or constant temperature conditions by Langevin thermostat. The simulations reveal that Young’s modulus and tensile strength exhibit little dependence on the boundary condition and thermostat while the failure strain of the nanowires increases with fixed boundary conditions compared to the nanowires subjected to periodic boundary conditions. The failure behaviors, which are quantified by our novel ductility failure probability parameter, exhibit larger, but limited variations depending on the boundary condition, but the trend is mixed and not conclusive.

The remarkably abnormal growth behavior of columnar grains and the formation of Σ3 grain boundaries (GBs) were studied via plastic deformation and annealing based on an electron backscattering diffraction (EBSD) investigation. Driven by the stored energy and GB mobility, coarse austenite columnar grains were formed by the abnormal growth of fine equiaxed grains with higher grain orientation spread (GOS) values in the reducing atmosphere of hydrogen. Moreover, extraordinarily coarse columnar grains with high GOS values and non-{1 1 1} texture were formed by microstructure inheritance during γ → α transformation. In addition, slender ferritic columnar or island grains with Σ3 GBs and low GOS values were generally obtained, and the formation mechanism was strictly associated with the Kurdjumov-Sachs (K-S) relationship, which was induced during variant selection driven by the GB mobility and surface effect in the reducing atmosphere of hydrogen.

The soils of shrublands are important for organic carbon storage in terrestrial ecosystems, but geographical patterns and environmental controls of soil organic carbon (SOC) remain largely understudied compared to other terrestrial ecosystems, leaving a significant gap in our understanding of terrestrial ecosystem carbon budgets. Here, we quantified SOC density (SOCD) and its potential determinants based on a comprehensive dataset with a consistent stratified random sampling of extensive soil profiles down to the parent material or to one meter depth across 1211 sites across China. Our up-to-date estimate of SOCD in Chinese shrublands is an average of 8.36 kg m−2, and ca. 43% of SOC is stored in the upper 20 cm relative to the one meter top soil, which is higher than estimates for shrublands globally. We also observed that SOCD was positively related to shrubland biomass and more so with belowground biomass. Furthermore, SOCD was positively related to mean annual precipitation (MAP), soil total nitrogen (N), phosphorus (P), clay and silt percent, but decreased with increasing mean annual temperature (MAT). Dark felty soils stored the highest SOCD and frigid desert soils stored the lowest. Soil total nitrogen (N), MAP, soil type, MAT, and belowground biomass, soil clay, and pH were the best predictors of total SOCD in Chinese shrublands. We concluded that Chinese shrubland soils store the lowest density of organic carbon so far recorded compared to forests and grasslands, and that the vertical distribution of SOC in Chinese shrublands was much shallower. While both climate (in particular MAP) and soil total N exerted dominant control over geographical patterns of SOCD across Chinese shrublands, soil type also played a significant role. Our study also emphasizes this key role of edaphic variables in determining the SOCD of shrublands and that they should be better incorporated into large-scale assessments of SOC dynamics. Our study extends existing work conducted in forest and grasslands and provides the most up-to-date knowledge on benchmark values for SOCD in Chinese shrublands, with important implications for predicting the fate of C stored in shrubland soils in response to climate change.

Conductive graphene/polymer nanocomposites have drawn particular attention owing to their great promising in various environmental and energy-related applications. A percolation theory based on variation of conductive filler fraction has been demonstrated as the central guide for their fabrications. However, it typically fails in some special cases since the assumption has ignored the effect of interfacial interaction between the conductive nanofillers and the material matrix. Herein, we employ a graphene/poly(vinyl alcohol) model to study the effect of interfacial interaction on their electrical conductivity by using two types of graphene with different oxygen content. We further demonstrate “cage effect” as a critical role on their conductivities, which arise from the interfacial hydrogen bonding interaction between the graphene nanofiller and PVA matrix. A “cage effect” modified percolation theory gave an excellent match with the experimental data. Notably, such “cage effect” can be effective alleviated by applying a hot drawing treatment, thus achieving a higher electrical conductivity. As such, we successfully fabricate a graphene/PVA composite with a superior electrical conductivity up to 25 S m−1 at a 6.25 wt% graphene. Its excellent electronic stability after multiple bending operations was also verified in a laboratory prototype device to confirm its suitability for flexible electronics.

The global total of protected areas to conserve biodiversity is increasing steadily, while numerous studies show that they are broadly effective. That said, how will current conservation strategies work, given the current and expected changes to the global climate? The giant panda is a conservation icon and exceptional efforts protect its remaining habitats. It provides a unique case study to address this question. There are many studies on the projected loss of habitats as climate warms, but few consider the geographical arrangement of future habitats, current protected area, and species’ dispersal abilities. Most alarmingly, we expect much greater habitat fragmentation after climate change. Here, we combine long-term data on giant pandas with climate-change scenarios to predict future habitat loss and distribution in the Min Shan of Sichuan and Gansu, China. We employ metapopulation capacity as a mechanistic measure of a species’ response to habitat fragmentation. The results show that climate changes will lead to 16.3 ± 1.4 (%) losses of giant panda habitats. Alarmingly, 11.4% of the remaining habitat fragments would be smaller than the extinction threshold area as the extent of fragmentation increases nearly fourfold. The projected fragmentation of giant panda habitats predicts 9% lower effectiveness inside the protected area network compared with that outside of reserves. A 35% reduction will occur in future effectiveness of reserve networks. The results challenge the long-term effectiveness of protected areas in protecting the species’ persistence. They indicate a need for integrating both natural processes and dynamic threats over a simple reliance on individual static natural reserves.

We present a theoretical investigation on the terahertz (THz) absorption by long-period InAs/GaSb type-II superlattices (SLs) with inverted band structures. It is found that in such SLs the band inversion causes a significant electron–hole hybridization and a strong THz absorption can be induced by this hybridization. The THz absorption coefficient is even larger than mid-infrared absorption coefficient for short-period InAs/GaSb SLs. Moreover, we find that the strong THz absorption can be further improved and optimized by the proper choice of InAs/GaSb layer widths. The interesting absorption features are well manifested in hybridization gaps and optical transition matrix elements. This study is pertinent to the potential application of long-period inverted InAs/GaSb type-II SLs as high-efficiency THz photodetectors.

Evolution of microstructure and tensile properties of extruded AZ31 alloys through Ca addition have been systematically investigated in this paper. Results show that Al–Mn and Al2Ca phases scattered along extruding direction exist in extruded AZ31-xCa (0.5 and 1 wt%Ca) alloys. AZ31-1 wt%Ca alloys exhibit finer microstructure with mean grain size of ~2.79 μm in comparison with AZ31-0.5 wt%Ca alloys, which is mainly related to the dynamic recrystallization (DRX) and the inhibition of grain coarsening by Al2Ca phase. In addition, the increased Ca content weakens the {0001} basal texture of extruded AZ31 alloys owing to the formation of Al2Ca phase. The comprehensive mechanical properties of extruded AZ31 alloys have an obvious improvement by adding Ca element owing to the grain refinement strengthening, second phase strengthening and texture strengthening.

The silicon nanowire is a novel nanometer-scale structure which can be used in various electronic and optoelectronic devices. While the plastic deformation and failure mechanisms, including the brittle-to-ductile transition at room temperature, of nanowires have been studied both experimentally and theoretically, the fundamental atomic-scale mechanisms of these behaviors still remain incompletely understood. In this article we study the mechanical and failure behaviors of the [110]-oriented single-crystalline silicon nanowires by performing uniaxial tensile tests using molecular dynamics simulations with three modified embedded-atom-method (MEAM) potentials, referred to as Baskes, Lee, and Lee-modified. The effects of several key parameters such as size, temperature, and strain rate are investigated. A preliminary examination of the three MEAM potentials reveals that Lee and Lee-modified models outperform Baskes model in predicting the thermal expansion coefficient and surface energies. The uniaxial tensile simulations show that some mechanical properties such as Young’s modulus and tensile strength exhibit size-dependence while there is little size-effect on the failure strain. A novel parameter named the ductile failure probability is introduced to quantify the failure behavior of the nanowire during the tensile test, which scales from 0 for the pure brittle to 1 for the pure ductile mode failure. Overall, the ductile failure probability increases with decreasing size and increasing temperature in all of the three models. The Baskes nanowires exhibit the most ductile failures among the three models whereas most Lee-modified nanowires fail through fractures on the (111) plane. The Lee model shows some intermediate levels of ductile failure behavior. The difference due to the strain rate is very small, but overall nanowires become slightly more brittle as the strain rate decreases.

The Si1−xGex thin layer is fabricated by two-step Ge ion implantation into (0 0 1) silicon. The embedded SiGe nanoclusters are produced in the Si1−xGex layer upon further annealing. The number and size of the nanoclusters changed due to the Ge diffusion during annealing. Micro defects around the nanoclusters are illustrated. It is revealed that the change of Si–Si phonon mode is causing by the nanoclusters and micro defects.

Closing the energy budget at flux measurement sites is problematic, even when the fetch extends over flat, homogeneous surfaces with low vegetation cover. We used the residual energy balance and ordinary least square (OLS) linear regression methods to quantify spatial variability in soil heat flux contributing to energy balance closure (EBC), by deploying a mobile energy system within the footprints of three Eddy-covariance towers located in the steppe of Inner Mongolia, China. The EBC at the study sites had a daily average residual of 8–19 W m−2 with OLS slopes of 0.83–0.96. The EBC was better achieved at the wet site than at the dry site. The spatial variability in soil heat flux was 48 W m−2 (13% of Rn) during the day and 15 W m−2 (34%) at night, with an average of 29 W m−2 (24%) across the three sites. A 9% OLS slope difference due to this variability was recorded from our eight plot measurements. A large amount of missing energy (110 W m−2 at peak) could occur with decreasing OLS slope of 23% across the three grassland sites when soil heat flux is not taken into account. In particular, heat storage in the top soil layer not only influenced the magnitude of EBC, but also adjusted soil heat flux to match the ‘truth schedule’. Heat storage in the top soil layer comprised half of the soil heat flux when the heat flux plate was deployed at a depth of 30 mm. If this part of heat storage was neglected, the residual of EBC would increase as large as 60 W m−2 with OLS slope decreasing 9%. Comparing them with the multiple-location soil heat flux measurements, the single-location measurements from near the Eddy-covariance towers obtained a slightly better EBC with the OLS slope increasing by 4%.

SiGe nanoparticles with uniform diameter of about 30 nm in the top silicon of silicon on insulator (SOI) were synthesized by Ge ion implantation combined with subsequent annealing process. The density of those nanoparticles is 6 × 10 7 /cm 2 . These nanoparticles are formed by agglomeration of the recoil atoms and the migrated adatoms. The method presented in this study will allow efficient fabrication of uniform SiGe nanoparticles into SOI.