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BaTiO3 thin films emerge as a highly promising material platform for integrated photonics due to their outstanding electro‐optic properties and diverse functionalities. Despite extensive studies, there remains a notable gap in the understanding of the intricate relationship between the phase structure, domain switching kinetics and electro‐optic performance of these materials. By controlling the structural phase evolution, it is possible to gain deep insights into the physical mechanisms underlying the electro‐optic performance. Here, the phase constitution of BaTiO3 epitaxial thin films is successfully tuned by the insertion of a GdScO3 buffer layer. Continuous polarization rotation paths are observed from an out‐of‐plane tetragonal‐like phase, to an intermediate rhombohedral‐like phase, and finally an in‐plane tetragonal‐like phase, achieving an enhanced effective electro‐optic coefficient of 175 pm V−1 compared to unbuffered films. Furthermore, by in situ second harmonic generation microscopy and electro‐optic measurements, the domain switching behaviors in both statistical and spatially resolved manners are examined, resulting in a clear delineation of the key domain nucleation processes. The in‐depth explorations of these structural mechanisms and kinetics inform the rational design of strong electro‐optic thin films and help in the realization of high‐performance integrated photonic devices such as electro‐optic modulators and multilevel phase shifters. [ABSTRACT FROM AUTHOR]

Earth's lower mantle is a potential water reservoir. The physical and chemical properties of the region are in part controlled by the Fe3+/ΣFe ratio and total iron content in bridgmanite. However, the water effect on the chemistry of bridgmanite remains unclear. We carry out laser-heated diamond anvil cell experiments under hydrous conditions and observe dominant Fe2+ in bridgmanite (Mg, Fe)SiO3 above 105 GPa under the normal geotherm conditions corresponding to depth > 2300 km, whereas Fe3+-rich bridgmanite is obtained at lower pressures. We further observe FeO in coexistence with hydrous NiAs-type SiO2 under similar conditions, indicating that the stability of ferrous iron is a combined result of H2O effect and high pressure. The stability of ferrous iron in bridgmanite under hydrous conditions would provide an explanation for the nature of the low-shear-velocity anomalies in the deep lower mantle. In addition, entrainment from a hydrous dense layer may influence mantle plume dynamics and contribute to variations in the redox conditions of the mantle. The large low-shear-velocity anomalies in the deep lower mantle below 2300 km depth may relate to H2O-induced ferrous iron stability in bridgmanite, according to laser-heated diamond anvil cell experiments. [ABSTRACT FROM AUTHOR]

Methane and other gases released from soft sediments are among the main sources of greenhouse gases in the atmosphere. In this paper, a growth model for isolated bubbles in the sediments was established based on the theory of linear elastic fracture mechanics. Water level drop experiments were conducted using magnesium lithium philip silicate transparent soils, and the changes in bubble pressure and morphology during water level drop were analyzed. The experimental results show that there is a critical pressure for bubble growth caused by a drop in water level. Bubbles only start to grow by fracturing the overlying sediments when the water level drops to the critical value because the critical bubble pressure is lower than the actual bubble pressure. The strength of soil, depth of the bubble position, longitudinal length of bubble, and amount and rate of water level drop are key factors affecting isolated bubble growth. Bubbles in the soils with higher strength are more difficult to reach the critical state but have a faster growth rate once they do reach it. The depth of bubble position only affects the time reaching the critical state and does not impact the post-growth process. Deeper bubbles are more difficult for initiating growth. For bubbles at the same depth, larger bubbles begin growing earlier. As bubbles become larger, the growth rate of the bubble increases progressively faster. Faster water level drops result in shorter times to reach their critical state and accelerate their growth rate. [ABSTRACT FROM AUTHOR]

The input of fresh organic carbon into soils can stimulate organic carbon mineralization via priming effects (PEs). However, little is known about the characterization of PEs in coastal wetlands. We investigated the PEs of two salt marshes (Suaeda salsa and Phragmites australis) in the Yellow River Delta by adding 13C-labeled glucose to soils collected from the 0–10 cm and 20–30 cm layers of both salt marshes. The addition of glucose produced a significant positive PE in both soil layers for both vegetation types. There were no differences in the PE of the topsoil layer between the two vegetation types (p > 0.05), whereas the PE of S. salsa was 19.5% higher than that of P. australis in the subsoil layer (p < 0.05). In addition, the topsoil layer showed a higher average PE of 29.1% compared to that of the subsoil layer for both vegetation types (p < 0.05). The differences in the PEs between the two vegetation types and the two layers could be associated with a differential soil salinity, substrate availability, and microbial community structure. Our findings highlight the important role of PEs in regulating the soil carbon storage of coastal salt marshes, which should be considered when assessing and modeling the soil carbon cycling of coastal wetlands. [ABSTRACT FROM AUTHOR]

Aluminum hydride (AlH3), as a potential new metal fuel, has attracted extensive attention in the field of hydrogen storage materials, propellants and energetic materials due to its excellent properties. In this paper, a new organic liquid phase reduction method was used to prepare AlH3, and the microstructure and composition of the prepared samples were characterized by SEM–EDS, XRD, FT-IR, XPS, etc. The main crystal phase of the prepared AlH3 was α-AlH3, with high quality and no other impurities. The thermal decomposition behavior and non-isothermal reaction kinetics of AlH3 were investigated by TG-DSC. The results show that there are three exothermic stages in the heating process of AlH3: dehydrogenation of AlH3, first oxidation of Al, and second oxidation of Al. The activation energy of the dehydrogenation of AlH3 is 77.8675 kJ/mol (Kissinger method) and 81.4862 kJ/mol (Ozawa method), respectively. The morphology evolution of AlH3 particles during the heating process (300–3000 K) was simulated using a reaction kinetics method based on the ReaxFF force field. The response behavior of AlH3 in the instantaneous high-temperature detonation environment was investigated using the high-energy laser-induced shock wave technique. Under the impact of a high-energy laser (1006 mJ), the AlH3 sample undergoes an ultra-fast reaction and generates a large amount of plasma. The expansion of the plasma pushes the surrounding air to form a supersonic shock wave and propagates forward. The shock wave propagation velocity of AlH3 is 690.99 m/s in the range of 2.1–12.35 μs, and the higher the laser energy, the faster the shock wave propagation velocity. This study provides the basis for the application of AlH3. [ABSTRACT FROM AUTHOR]

The lunar surface and interior are highly reducing, resulting in the virtually absence of ferric ion. However, recent studies suggest the presence of ferric iron in lunar samples, and in most cases they were found in amorphous silicates (e.g., glass beads) measured by TEM–EELS. In this work, we conducted a systematic TEM–EELS analysis on the iron valence states of Chang'e-5 impact glass beads. The Fe3+/ΣFe ratio of each silicate glass sample was determined from integral intensity of Fe L3 and L2 edge. The measurements show a positive correlation between the dwell time and Fe3+/ΣFe ratio, which reveals that ferric iron can be significantly produced by electron beam bombardment under routine analytical condition. The calculated Fe3+/ΣFe with short dwell times (≤ 20 ms) in our Chang'e-5 impact glass beads show no detectable inherent ferric iron, suggesting that the ferric iron is not ubiquitous as previously reported. It is obvious that a careful control of experiment conditions is critical to determine the inherent redox state of other beam-sensitive terrestrial and extraterrestrial samples. [ABSTRACT FROM AUTHOR]

Background: Liver transplantation has made significant progress in recent decades. Lung cancer is one of the most frequently occurring cancers after liver transplantation. However, the risk of lung cancer among liver transplant patients compared with the general population is unclear. The aim of this meta‐analysis was to assess the risk of developing lung cancer after liver transplantation. Methods: All eligible studies published in PubMed, Web of Science, and Embase from database inception to April 2022 were included. Standardized incidence ratio was used to describe the increased risk of lung cancer in liver transplant recipients as compared with the general population. The random‐effects model was used for the calculations. A funnel plot and Egger test were performed to assess the potential publication bias. Results: Our meta‐analysis included 15 studies, which involved 76,897 liver transplantation patients. Studies included in this review showed significant heterogeneity (I2 = 65.3%; p < 0.001), which required a random‐effects model for effect pooling. The results indicated a significant higher risk of developing lung cancer in liver transplant patients than the general population with a pooled SIR of 2.06 (95% CI: 1.73, 2.46, p < 0.001). When stratified by region, no significant regional difference was observed. It showed a similarly doubled risk of lung cancer in Europe and North America, but an insignificantly increased risk in Asian populations. The sensitivity analysis by removal and substitution of each literature did not change the results. Conclusion: Our meta‐analysis suggests that liver transplant patients are twice as likely as the general population to develop lung cancer. Further research on risk factors for the development of lung cancer after liver transplantation should be conducted and appropriate surveillance protocols should be developed to reduce the risk of its occurrence. [ABSTRACT FROM AUTHOR]

Evidence suggests that college students' future-related feelings and cognition may influence their trust in government. This study aims to explore whether the association between college students' future time perspective and trust in government is mediated through the consideration of future consequences (CFC). A cross-sectional survey was used to collect data from 1,617 college students (86.6% women) aged 17 to 31 years in China via an online questionnaire. The results showed that the students' positive, negative and confused future orientation was positively associated with their trust in government. The consideration of far- future consequences positively mediated the relationship between a positive future orientation and trust in government. These findings support the possibility to evaluate college students' government trust level according to their future orientation, which will improve their positive political participation. [ABSTRACT FROM AUTHOR]

The presence of water may contribute to compositional heterogeneities observed in the deep lower mantle. Mg-rich ferropericlase (Fp) (Mg,Fe)O in the rock-salt structure is the second most abundant phase in a pyrolitic lower mantle model. To constrain water storage in the deep lower mantle, experiments on the chemical reaction between (Mg,Fe)O and H2O were performed in a laser-heated diamond-anvil cell at 95–121 GPa and 2000–2250 K, and the run products were characterized combining in situ synchrotron X-ray diffraction measurements with ex-situ chemical analysis on the recovered samples. The pyrite-structured phase FeO2Hx (x ≤ 1, Py-phase) containing a negligible amount of Mg (<1 at%) was formed at the expense of iron content in the Fp-phase through the reaction between (Mg,Fe)O and H2O, thus serving as water storage in the deepest lower mantle. The formation and segregation of nearly Mg-free Py-phase to the base of the lower mantle might provide a new insight into the deep oxygen and hydrogen cycles. [ABSTRACT FROM AUTHOR]

Phase change memory has been considered as the next generation in non-volatile electronic data storage. The property modulation of such materials by the doping of rare-earth elements has drawn a lot of attention, which motivates us to search for the optimal dopants and reveal the underlying mechanisms. Here, we investigate the role of Gd as a dopant in Ge2Sb2Te5, which exhibits higher crystalline resistance and better thermal stability and antioxidant capacity than the undoped counterpart. Moreover, Gd dopants suppress both the processes of phase transition and grain growth. The crystalline structure remains unchanged with Gd dopants and vacancies are randomly distributed. Furthermore, the bonding mechanism was theoretically investigated. In the amorphous state, Gd atoms modify the local structures around Ge, Sb, and Te atoms. The large coordination number of Gd and the "Gd–Te distorted pentagonal bipyramidal-like" structure can be attributed to the good thermal stability. These microscopic findings figure out some of the key issues about the bonding mechanism, electrical properties, and crystallization behaviors of Gd doped phase change memory materials, which could be useful for storage devices. [ABSTRACT FROM AUTHOR]

As an important part of carbon dioxide capture, utilization and storage (CCUS), the progress of injecting CO2 into oil reservoirs could increase the recovery rate and achieve large-scale carbon storage. It has become one of the most important carbon storage methods around the world. This paper selected the tight sandstone of the fourth member of the Quantou Formation in the southern Songliao Basin to carry out a CO2 storage physical simulation experiment. Representative samples were collected at 24 h, 72 h, 192 h and 432 h to study the CO2 water-rock interaction and to analyze the mineral composition, pore structure and the evolutionary characteristics of physical reservoir properties over time. Physical property analysis, Ion analysis, X-ray diffraction mineral analysis, QEMSCAN mineral analysis, scanning electron microscopy and high-resolution CT scanning techniques were adopted. The main points of understanding were: (i) It shows a differential evolution of different minerals following the storage time of CO2, and carbonate minerals are mainly dissolved with ankerite as a typical representation; a small amount of calcite is formed in 24 h, and dissolved in the later period; feldspar and quartz were partially dissolved; clay mineral precipitation blocked the pores and gaps; (ii) The evolution in mineral variation leads to the complexity of pore structure evolution, following a trend of "small pores decreasing and large pores increasing" with extending storage time. The final porosity and permeability ratios gradually increase from 4.07% to 21.31% and from 2.97% to 70.06% respectively; (iii) There is a negative correlation between the increasing ratio and the original physical properties of the tight stones due to the dissolution of ankerite. Relevant research could provide scientific guidance and technical support for the geological storage of CO2 in lacustrine tight continental sandstones and the development of CCUS technology. [ABSTRACT FROM AUTHOR]

The Watts–Strogatz networks are important models that interpolate between regular lattices and random graphs, and Barabási–Albert networks are famous models that explain the origin of the scale-free networks. Here, we consider the first encounters between two particles (e.g., prey A and predator B) embedded in the Watts–Strogatz networks and the Barabási–Albert networks. We address numerically the mean first-encounter time (MFET) while the two particles are moving and the mean first-passage time (MFPT) while the prey is fixed, aiming at uncovering the impact of the prey's motion on the encounter time, and the conditions where the motion of the prey would accelerate (or slow) the encounter between the two particles. Different initial conditions are considered. In the case where the two particles start independently from sites that are selected randomly from the stationary distribution, on the Barabási–Albert networks, the MFET is far less than the MFPT, and the impact of prey's motion on the encounter time is enormous, whereas, on the Watts–Strogatz networks (including Erdős-Rényi random networks), the MFET is about 0.5–1 times the MFPT, and the impact of prey's motion on the encounter time is relatively small. We also consider the case where prey A starts from a fixed site and the predator starts from a randomly drawn site and present the conditions where the motion of the prey would accelerate (or slow) the encounter between the two particles. The relation between the MFET (or MFPT) and the average path length is also discussed. [ABSTRACT FROM AUTHOR]

Additives in thermoelectric materials are conventionally considered as either extrinsic defects or second phases regardless of their dynamic processes. Herein, In4SnSe4, with inherent low thermal conductivity, is introduced into n‐type PbTe. It is revealed that In4SnSe4 decomposes incompletely at high temperatures, in which around 80% of In4SnSe4 dissolves into InSe and Sn, while 20% forms as nano‐precipitates. Benefiting from the incomplete decomposition, PbTe‐0.1%In4SnSe4 presents superior thermoelectric performance compared to the stepwise and compositionally identical PbTe‐0.4%InSe‐0.1%Sn. The residual In4SnSe4 along with Sn and InSe jointly contribute to the synergetic optimization of carrier mobility and lattice thermal conductivity in PbTe‐0.1%In4SnSe4. As a result, the room‐temperature dimensionless figure of merit (ZT) of ≈0.4 and the ZTave of ≈0.83 at 300–573 K are obtained, and an experimental maximum thermoelectric conversion efficiency (η) of ≈2.5% (ΔT ≈ 400 K) is obtained, demonstrating significant research progress in n‐type PbTe. This work indicates that the In4SnSe4 incomplete decomposition effectively decouples the electron and phonon transports in n‐type PbTe and the strategy of utilizing the unstable additives is proven feasible. Additionally, more dynamic behaviors of additives are worth expecting and may promote more achievements for other thermoelectric systems. [ABSTRACT FROM AUTHOR]

Bolus volume is very important in the biomechanics of swallowing. By noninvasively characterizing swallow responses to volume challenges, we can gain more knowledge on swallowing and evaluate swallowing behavior easily. This study aimed to evaluate the impact of bolus volume on the biomechanical characteristics of oropharyngeal swallowing events with a noninvasive sensing system. Fifteen healthy male subjects were recruited and instructed to swallow 5, 10, and 15 ml of water. The sensing system consisted of a tongue pressure sensor sheet, bend sensor, surface electrodes, and a microphone. They were used to monitor tongue pressure, hyoid activity, surface EMG of swallowing-related muscles, and swallowing sound, respectively. In addition to the onset, the peak time and offset of the above four structures, certain characteristics, such as the duration, peak value, and interval of the structure motions, were measured during the different drinking tasks. The coordination between the hyoid movement and tongue pressure was also assessed. Although no sequence of the structural events changed with volume, most of the timings of the structural events were significantly delayed, except for certain hyoid activities. The swallowing volume did not affect the active durations of the monitored structures, the peak values, or intervals of tongue pressure and supra- and infrahyoid muscle activity, but certain hyoid kinetic phases were prolonged when a larger volume was swallowed. Additionally, sequential coordination between hyoid movement and tongue pressure was confirmed among the three volumes. These findings suggest that oropharyngeal structural movements change in response to bolus volume to facilitate safe swallowing. The noninvasive and quantitative measurements taken with the sensing system provide essential information for understanding normal oropharyngeal swallowing. [ABSTRACT FROM AUTHOR]

The gas in soft cohesive sediments tends to transport through fractures or cracks, and the study on fracture toughness of soft soil is an important component of the research on gas migration. A method for measuring fracture toughness of soft sediments is proposed in this paper. The gas injection tests on soft soil at constant flow rate were conducted, and the fracture toughness of soft soil could be calculated combined with the theory of linear elastic fracture mechanics based on the gas pressure and the orifice diameter. Through direct observation of the bubble growth in Laponite RD transparent soil, the law of gas pressure variation and the mechanism of bubble fracture growth in soft soil were further verified. The methods and instruments proposed in this paper are convenient and easy for operating, which are suitable for measuring fracture toughness of soft soil in laboratory. The fracture toughness of soft soil obtained by the method presented in this paper is consistent with the measurements of the in-situ soft clay proposed in the literature, which suggests that the fracture toughness measurement method of soft soil proposed in this paper is reasonable. [ABSTRACT FROM AUTHOR]

The vegetation in the desert riparian zone represents a critical barrier in the maintenance of the ecosystem's balance. However, in recent years, the vegetation degradation of the riparian zone has seriously hindered economic development and ecological environment conservation. Based on a field investigation and literature, the mechanisms of vegetation degradation in the lower reaches of the Ugan River are discussed in this study through the analysis of plant coverage, diversity, substitution rate, distribution pattern, grey correlation analysis, and the relationship with groundwater depth. The results showed that the vegetation coverage in this region is relatively low when the water depth exceeds 4 m. Furthermore, the Shannon–Wiener index, the Simpson index, and the Pielou index all decreased with increases in water depth. Woody plants are the main species maintaining the ecological balance of the region with an aggregation distribution pattern. The degradation of vegetation is the result of the lack of water sources and the intense water consumption caused by human activities (especially agricultural). To promote ecological balance and vegetation restoration, the relative optimal water depth range should be maintained within 2 to 5 m as well as proper control of human activities. In addition, the degraded vegetation can gradually be restored using point and surface (i.e., flowering in the center and spreading to the surrounding areas). The results can provide a scientific basis for vegetation restoration and ecological conservation in the lower reaches of China's Ugan River. [ABSTRACT FROM AUTHOR]

Micrometeorite impacts and solar wind irradiation, the dominant space weathering (SW) processes, largely modified compositions and microtexture of soil materials on the Moon. Here, we report the SW characteristics of the Chang'e‐5 lunar soils from mid‐high latitude (43.06°N). All mineral phases exposed on the surface of a single basalt clast have a vapor deposit layer, whereas the textures of the solar wind irradiation‐damaged zone are dependent on the host mineral species. Nanophase Fe (npFe0) particles are spherical in the amorphized zone of pyroxenes, elongated in ilmenite, and irregular on the jagged surface of iron sulfide, but not found in Fe‐poor merrillite. Vesicles were found in the damaged zone of ilmenite and merrillite, but with different shapes. The observations were compared to Apollo samples and demonstrate no significant altitude‐dependent effects on the SW, which is important for decoding the reflectance spectra of the Moon. Plain Language Summary: The lunar surface has been suffering intense meteorite impacts and solar wind irradiation for billions of years, which heavily modifies its physical properties, chemical compositions and mineralogical features, and in turn, the optical reflectance spectra of the Moon. The meteorite impacts are random events, but the intensity of solar wind irradiation is latitude dependent. However, all Apollo and Luna missions landed in a narrow and low range of lunar latitude. The Chang'e‐5 (CE‐5) mission returned lunar soil samples from a middle latitude (43.06°N), providing unique samples for study of lunar space weathering (SW). In this paper, we report the SW features of various minerals from a single basaltic clast of the CE‐5 sample. Our observations reveal phase‐dependent effects on the SW. Furthermore, the CE‐5 lunar soil shows no significant differences from those of Apollo samples, suggestive of little latitude‐dependent effects on lunar SW. Key Points: The space weathering (SW) characteristics of lunar soils returned by Chang'e‐5 landing at the mid‐high latitude site are reportedMicroscopic textures of SW depend on mineral species but show no relationship with the latitude of sampling siteThe SW products by micrometeorite impacts and solar wind irradiation are distinguished [ABSTRACT FROM AUTHOR]

In order to improve thermal conductivity, energy performance, and combustion performance of the aluminum-containing thermite, nanocarbon materials were added to thermite. Aluminum/molybdenum and trioxide/nanocarbon materials (Al/MoO3/NCM) were fabricated by electrostatic spinning technology. The Al and MoO3 particles of the nAl/MoO3/NCM thermite are much smaller than nitrocellulose (NC); thus, the two components can be better attached to NC fibers. Results on thermal conductivity demonstrated that the addition of NCM can improve the thermal conductivity of Al/MoO3, and the addition of reduced graphene oxide (RGO) has a more significant impact on thermal conductivity. Energy performance analysis results indicated that the energy performance of Al/MoO3/NCM thermite spinning is the best when the value of combustion oxygen equivalent ratio (Φ) is 0.90–1.00. The combustion performance results show that the addition of NCM can significantly increase the combustion rate of thermites, and the addition of RGO improves its combustion rate the most, followed by carbon nanotubes (CNT) and nanoflake graphite (NFG) being the lowest. By changing the shape of the Al/MoO3/NCM charge and the internal composition of the charge, the sensitivity of the agent can be adjusted, and the matching performance and use performance of the electric igniter can be improved. [ABSTRACT FROM AUTHOR]

Periodontitis is the leading cause of tooth loss in adults, and psychological factors play an important role in the development of periodontitis. To elucidate the adverse effects of psychological stress on the inflammatory process and redox status of periodontitis tissue, fifty male Sprague-Dawley rats were divided into the control, experimental periodontitis, psychological stress, experimental periodontitis plus psychological stress, and experimental periodontitis plus psychological stress plus fluoxetine groups. Chronic unpredictable mild stress (CUMS) was used to establish psychological stress, and silk ligature was used to induce experimental periodontitis. Four weeks later, stressed rats showed altered behaviour, serum hormone levels, and sucrose preference. More obvious alveolar bone loss and attachment loss and higher protein expressions of inflammatory cytokines were observed in the experimental periodontitis plus psychological stress group. The combination of CUMS and periodontitis had synergistic effects on increasing hypoxia-inducible factor-1α (HIF-1α) protein expression and reactive oxygen species (ROS) and malondialdehyde (MDA) contents and decreasing antioxidant enzyme activities compared with those in the stress or periodontitis groups. Moreover, psychological stress further increased p-IκBα and p-NF-κB p65 protein levels and decreased IκBα protein levels in periodontitis rats. Fluoxetine administration alleviated the adverse effects of psychological stress on the progression of periodontitis in rats. These results hint us that psychological stress could aggravate inflammation in periodontitis tissues, which may be partly due to local worsening of oxidative damage and further activation of the nuclear factor kappa-B (NF-κB) signalling pathway. [ABSTRACT FROM AUTHOR]

Rare‐earth sulfides are of research interest for lithium‐ion batteries (LIBs) due to their abundant lithium intercalation sites and low redox voltage. However, their electrochemical performances are not satisfactory because of poor conductivity and volume change upon electrochemical cycling. Herein, nanoarchitectures of γ‐Ce2S3 encapsulated in a hollow mesoporous carbon nanosphere (Ce2S3@HMCS) are fabricated using the self‐template strategy combined with the in‐sphere sulfuration method and tested as an LIB anode. The void space between the Ce2S3 core and the outer layer of the carbon nanosphere has been properly designed and modulated to achieve excellent electrochemical performance in terms of electronic conductivity, reversibility, and rate capability. The reversible capacity of Ce2S3@HMCS is 2.6 times that of the pure Ce2S3 anode, which can gradually increase and maintain a capacity of 282 mAh·g−1 at a current density of 1 A·g–1, and a high Coulombic efficiency (~100%) can be achieved even after 1000 cycles. This good performance is attributed to the unique yolk–shell nanostructure with a highly crystallized and stable Ce3S2 core and volume expansion buffer space upon lithiation/delithiation. Ex situ X‐ray diffraction and nuclear magnetic resonance results indicate that the lithiation of Ce2S3@HMCS is an intercalation process. This study represents an important advancement in precise structural design with in‐sphere sulfuration and sheds light on a potential direction for high‐performance lithium storage. [ABSTRACT FROM AUTHOR]

Investigation of gas migration in saturated soil is of great theoretical and practical significance in marine science and engineering. The transport of gas bubbles in soil and its effects on soil physical and mechanical properties can be further studied. Gas injection and permeability tests were conducted using a self-developed oedometer with gas injection and water infiltration. Before the gas injection test, the remolded saturated soil was consolidated in an oedometer device to an effective vertical stress of 100 kPa. Gas injection tests were then performed to investigate the transport mechanism of bubbles in saturated soil and the changes in water permeability after gas injection. The results show that it is difficult for gas to migrate through capillary invasion and fracturing from the pore scale owing to the high gas entry pressure in fine-grained sediments. Hence, initial gas migration mechanism in pore scale is elastic-plastic expansion. The scale of cavities expands from micron to millimeter during gas injection, and gas pressure for fracturing reduces with the expansion of cavities. The fracturing initiated in millimeter scale and gas invades further into the soil. Interconnections of cavities and cracks resulting in an increasing of drainage rate and coefficient of permeability. [ABSTRACT FROM AUTHOR]

It remains a daunting task to quantify the configurational entropy of a material from atom‐revolved electron microscopy images and correlate the results with the material's lattice thermal conductivity, which strides across statics, dynamics, and thermal transport of crystal lattice over orders of magnitudes in length and time. Here, a proof‐of‐principle study of atomic‐scale visualization and quantification of configurational entropy in relation to thermal conductivity in single crystalline trigonal GeSb2Te4 (aka t‐GeSb2Te4) with native atomic site disorder is reported. A concerted effort of large t‐GeSb2Te4 single crystal growth, in‐lab developed analysis procedure of atomic column intensity, the visualization and quantification of configurational entropy including corresponding modulation, and thermal transport measurements enable an entropic "bottom‐up" perspective to the lattice thermal conductivity of t‐GeSb2Te4. It is uncovered that the configurational entropy increases phonon scattering and reduces phonon mean free path as well as promotes anharmonicity, thereby giving rise to low lattice thermal conductivity and promising thermoelectric performance. The current study sheds lights on an atomic scale bottom‐up configurational entropy design in diverse regimes of structural and functional materials research and applications. [ABSTRACT FROM AUTHOR]

The high level of trust in government in China has been attributed to the Chinese government's success in economic development. However, the increased public demand in China in recent years has made the public less likely to focus on the government's economic performance, which inspired us to explore the correlation between government's economic performance and trust in government. Based on the Asian Barometer Survey, this study examines the relationship between the government's economic performance and trust in government in China. The findings suggest that good economic performance by the government was positively associated with a high level of trust in government. High respect for authority was not only positively associated with trust in government but also weakened the relationship between the government's economic performance and trust in government. This study provides evidence that although the conventional concept of respect for authority may positively predict trust in government, it will weaken the effects of good economic performance by the government on trust in government. The results provide reference for governments in contexts similar to that in China seeking to improve their reputations. [ABSTRACT FROM AUTHOR]

Based on early experiences and current conditions, a future time perspective influences college students' behaviors, while psychological violence critically threatens college students' health. This study explored the relationship between a future time perspective and the psychological violence of perpetrators based on an online investigation of 1424 college students (87.1% women) aged 17 to 31 in China. The results showed that a future time perspective is significantly positively associated with psychological violence. Positive future orientation is negatively associated with psychological violence. Negative and confused future orientations are positively associated with psychological violence. These findings support the need to introduce an intervention regarding a future time perspective to reduce psychological violence among college students. [ABSTRACT FROM AUTHOR]

Background/aim: In order to enrich epidemiological knowledge regarding traumatic dental injuries (TDI) in China, and to further improve the treatment, prevention and education of TDI, the aim of this study was to retrospectively analyze the TDI that presented to the emergency dental department at the Stomatological Hospital in Xi'an, China.Methods: This retrospective study included all first-visit patients who presented with TDI at the Stomatological Hospital affiliated with the Fourth Military Medical University in Xi'an, China, between January 2013 and June 2019. Data were extracted using the terms of diagnosis of TDI from the hospital database.Results: Overall, 965 (606 males and 359 females) files were reviewed. The average age was 22.8 ± 13.4 years. Among the 2059 teeth injured (average of 2.1 teeth per patient), the maxillary incisors (1751; 85.0%) were the most prevalent teeth to present with injuries, while the main types of injuries were concussions (14.8%) enamel-dentin-fractures (14.50%) and enamel-dentin-pulp fractures (14.0%). After initial examination and diagnosis, 4.2% patients refused treatment.Conclusions: The epidemiological statistics of TDI in Xi'an, China show consistency with other studies from around the world, but they also vary in diagnosis proportion and the choice of treatments. This information may further instruct treatment, prevention and emergency resources distribution to target the high-risk groups. [ABSTRACT FROM AUTHOR]

The Lower Cambrian black shale at the northern margin of the Upper Yangtze Platform is an important source rock with large sedimentary thickness and high organic carbon content, which gives it important oil and gas exploration value. Restoring its developmental environment and clastic provenance is of great significance for the prediction of hydrocarbon source rock distribution. By systematic field outcrop sampling in the Chengkou area, South China, and geochemical testing, this study investigated the formation environment and source supply of the black shale and discusses the effect of climate change and terrigenous input on the formation of the black shale. It also reconstructs the process by which these excellent-quality hydrocarbon source rocks were formed. The results showed that the black shale has high Al2O3 content (7.38-13.90%), K2O content (1.01-2.93%), Na2O content (1.98-2.88%) and total Fe2O3 content (2.35-5.36%), and is enriched by trace elements such as V (average 242 µg/g), Cr (average 83 µg/g) and Ni (average 58 µg/g). CIA, K/Al and Rb/Al ratios indicate that the climate was warm and humid during the period of black shale deposition. V/Cr, U/Th, Ce/Ce* and MoEF-UEF indicate that the sedimentary waterbody underwent an anoxic → suboxic → anoxic → suboxic cycle. A positive Eu/Eu* anomaly also suggests the occurrence of early submarine hydrothermal activity. The Th/Sc - Zr/Sc chart indicates that the sedimentary components of the black shale did not undergo a recycling process, and it is therefore possible to effectively identify the location of the source. The Co/Th-La/Sc and La/Th-Hf diagrams confirm the presence of both felsic and mafic source rocks in the black shale. The Hannan paleo-uplift may have been an effective source area. [ABSTRACT FROM AUTHOR]

Objective: Early diagnosis remains the primary goal for leprosy management programs. This study aims to determine whether active surveillance of patients with leprosy and their contact individuals increased identification of latent leprosy cases in the low-endemic areas. Methods: This cross-sectional survey was carried out between October 2014 and August 2016 in 21 counties throughout Shandong Province. The survey was conducted among patients with leprosy released from treatment (RFT) and their contacts from both household and neighbors. Results: A total of 2,210 RFT patients and 9,742 contacts comprising 7877 household contacts (HHCs), including 5,844 genetic related family members (GRFMs) and 2033 non-genetic related family members and 1,865 contacts living in neighboring houses (neighbor contacts, NCs), were recruited. Among identified individuals, one relapsed and 13 were newly diagnosed, giving a detection rate of 0.12%, corresponding to 120 times the passive case detection rate. Detection rates were similar for HHCs and NCs (0.114% vs. 0.214%, P = 0.287). Analysis of the family history of leprosy patients revealed clustering of newly diagnosed cases and association with residential coordinates of previously-diagnosed multibacillary leprosy cases. Conclusion: Active case-finding programs are feasible and contributes to early case detection by tracking HHCs and NCs in low-endemic areas. Author summary: Leprosy has been eliminated as a public health problem in 1994 in Shandong Province. However, the district continues to report a relatively high number of cases of leprosy infection involving deformity. Several studies have shown that individuals in contact with people infected with leprosy are at high risk of developing the disease. Subclinical infections among such individuals are important in the chain of M. leprae transmission. Some hyperendemic areas show growing interest in active case finding (ACF). Recent data from the World Health Organization (WHO) show that high rates of relapsed patients, grade 2 disability (G2D) since 2011, and the extensive family history of leprosy among people in Shandong Province P.R. China, indicate a need to reconsider the current approach to leprosy prevention. Active case finding was conducted in 21 counties of Shandong Province among patients with leprosy released from treatment (RFT) and their contacts. We achieved a detection rate of 0.12%, which was much higher than the rate for passive case finding. Our ACF program confirmed the need to implement this strategy among families and neighbors of RFT patients in historically high-endemic areas of leprosy. The program could reduce the risk of G2D by facilitating early detection and treatment, thereby reducing the disease burden. [ABSTRACT FROM AUTHOR]

Random access memory devices that rely on phase changes are primarily limited by the speed of crystallization. However, imaging structural dynamics in working devices with nanoscale resolution remains elusive. Using an ultrafast liquid-quenching system in transmission electron microscope, we obtain a melt-quenched amorphous phase-change material Ge2Sb2Te5 nanosheet. We find that the applied incubation field (pretreatment) leads to nonuniform nucleus formation and growth in the amorphous Ge2Sb2Te5, accompanied by a slight change in electric properties. Moreover, the phase-change mechanism changes from the material inherent crystallization mechanism (nucleation-dominated) to the heterocrystallization mechanism, indicating the incubation period of nucleation might be bypassed. [ABSTRACT FROM AUTHOR]

Background: Aldehyde dehydrogenase 2 (ALDH2) and cytochrome p450 2E1 (CYP2E1) are important alcohol-metabolizing enzymes. The aim of this meta-analysis was to evaluate the association of ALDH2 rs671 and CYP2E1 rs2031920 polymorphisms with hepatocellular carcinoma (HCC) susceptibility in East Asians. Methods: A systematic search strategy was implemented in MEDLINE, PubMed, Scopus, Embase, and China Academic Journals databases. Nineteen case-control studies were selected for inclusion. Pooled odds ratios (ORs) and 95% confidence intervals (CIs) were calculated through random-effects or fixed-effects models. Subgroup analysis, meta-regression, sensitivity analysis, cumulative meta-analysis, and evaluation of publication bias were performed. Results: The overall meta-analysis did not find a significant association of ALDH2 rs671 and CYP2E1 rs2031920 genotypes with HCC susceptibility in East Asians. In addition, stratified analysis by country, Hardy-Weinberg equilibrium status, and source of controls also did not identify any association. Conclusion: The ALDH2 rs671 and CYP2E1 rs2031920 polymorphisms are not associated with HCC susceptibility in East Asians. [ABSTRACT FROM AUTHOR]

It is commonly accepted that psychological stress is closely associated with the occurrence and development of chronic orofacial pain. However, the pathogenesis underlying this process has not been fully elucidated. In the present study, we explored the role of N-methyl-D-aspartate receptors (NMDARs) and Jun N-terminal kinase (JNK) mediated intercellular communication between neurons and astrocytes in the spinal trigeminal nucleus caudalis (Vc) in the induction of masseter hyperalgesia by psychological stress in rats. We found that subjecting rats to 14 days of restraint stress (8 h/d) caused a significant decrease in body weight gain, behavioral changes and marked masseter hyperalgesia in the rats. We also found that exposure to restraint stress for 14 days caused the expression of pJNK in astrocytes in the Vc to significantly increase, and intrathecally infusing a JNK inhibitor significantly prevented restraint stress-induced masseter hyperalgesia in the rats. In addition, after exposure to restraint stress for 14 days, the stressed group exhibited a noticeably increased expression level of pNR2B in neurons in the Vc. Then, we intrathecally injected MK-801 (an NMDAR inhibitor) and ifenprodil (a selective NR2B subunit antagonist) and observed that the two types of inhibitors not only alleviated masseter hyperalgesia but also significantly inhibited the phosphorylation of JNK in the Vc after restraint stress; this indicates that the effect of NMDAR antagonists may influence the activation of astrocytic JNK. Furthermore, inhibitors of neuronal nitric oxide synthase (nNOS) activation and guanylate cyclase (GC) inhibitor could not only inhibit the expression of pJNK in the Vc, but also effectively alleviate masseter hyperalgesia induced by restraint stress. Taken together, our results suggest that NMDAR activation could increase JNK phosphorylation in astrocytes after restraint stress, which may depend on the nNOS-GC pathway. The intercellular communication between neurons and astrocytes in the Vc may play a key role in the induction of masseter muscle hyperalgesia by psychological stress in rats. [ABSTRACT FROM AUTHOR]

This study compared urban/rural trends in cigarette smoking rates among older male adults in China. Data were derived from the China Health and Nutrition Survey (N = 5,147). Logistic models were computed to assess the occurrence of cigarette smoking between 1991 and 2011 across urban/rural administrative districts. Cigarette smoking rates remained consistent (about 50%) in rural villages over the last two decades but decreased by about 1.1 percentage points annually in urban neighborhoods. After adjusting for individual and community characteristics, divergent urban/rural trends in cigarette smoking rates did not vary statistically. Trends in cigarette smoking may be associated with unbalanced social and economic development in urban and rural China, and are an indicator of social determinants of health inequalities. Results suggest tobacco control policies and interventions should specifically focus on older adults vulnerable to economic inequality. Findings have implications for health and economic inequality among older adults in general. [ABSTRACT FROM AUTHOR]

Abstract: Lead‐free tin sulfide (SnS), with an analogous structure to SnSe, has attracted increasing attention because of its theoretically predicted high thermoelectric performance. In practice, however, polycrystalline SnS performs rather poorly as a result of its low power factor. In this work, bulk sodium (Na)‐doped SnS single crystals are synthesized using a modified Bridgman method and a detailed transport evaluation is conducted. The highest zT value of ≈1.1 is reached at 870 K in a 2 at% Na‐doped SnS single crystal along the b‐axis direction, in which high power factors (2.0 mW m−1 K−2 at room temperature) are realized. These high power factors are attributed to the high mobility associated with the single crystalline nature of the samples as well as to the enhanced carrier concentration achieved through Na doping. An effective single parabolic band model coupled with first‐principles calculations is used to provide theoretical insight into the electronic transport properties. This work demonstrates that SnS‐based single crystals composed of earth‐abundant, low‐cost, and nontoxic chemical elements can exhibit high thermoelectric performance and thus hold potential for application in the area of waste heat recovery. [ABSTRACT FROM AUTHOR]

The variational Born iterative method (VBIM) is employed here to reconstruct 3-D objects with permittivity contrast buried in spherically multilayered media. The nonlinear inverse problem is solved iteratively via the conjugate-gradient method, and in each iteration, the scattered field is linearized by using the Born approaximation. The forward solver is provided by the method of moments combined with a Krylov subspace method. The dyadic Green’s function for spherically layered media is constructed in terms of the spherical vector wave functions by using the scattering superposition in the spherical coordinate system and then transformed into the Cartesian coordinate system. Thus, the inversion region is discretized into $N$ uniform cubic cells and the reconstructed result can be obtained in the Cartesian coordinate system by employing VBIM. Numerical results with high resolution are presented to validate the capability of our method in reconstructing 3-D multiple objects of arbitrary shapes buried in spherically multilayered media. [ABSTRACT FROM PUBLISHER]

We apply the forward scattering and inverse scattering algorithms to a cold unmagnetized plasma region within a multilayered background medium. Each layer has a different plasma frequency. The disturbed region in the plasma has an arbitrary shape, so it is an electromagnetic wave scatterer and can exist in any layer. The stabilized biconjugate-gradient fast Fourier transform (BCGS-FFT) algorithm is used to compute the scattered field. The scattered fields calculated by the BCGS-FFT yield excellent agreement with simulated results from the commercial software. In the inverse scattering process, the variational Born iterative method is used to reconstruct the relative permittivity, and thus the plasma frequency of the disturbed region. Multiple frequencies are adopted to determine the dispersive property of the plasma medium. [ABSTRACT FROM PUBLISHER]

ABSTRACT The method of moments (MOM) is applied to solve electromagnetic (EM) scattering problems in spherically multilayered media. A spectral-domain dyadic Green's function (DGF) in a spherically multilayered medium is constructed in terms of the spherical vector wave functions by using the method of scattering superposition in the spherical coordinate system. Its expression is later transformed to that in the Cartesian coordinate. We discretize the computational domain which contains the scatterer into N size-independent cells in the Cartesian coordinate. Based on the transformed DGFs, the volume integral equations can be solved by MOM combined with Krylov subspace iterative methods. In this letter, we choose the bi-conjugate gradient stabilized (BCGS) iteration method due to its fast convergence. Numerical results compared with FDTD solutions from a commercial software are presented to validate the accuracy and efficiency of our method. © 2017 Wiley Periodicals, Inc. Microwave Opt Technol Lett 59:526-530, 2017 [ABSTRACT FROM AUTHOR]

Phase change memory, which is based on the reversible switching of phase change materials between amorphous and crystalline states, is one of the most promising bases of nonvolatile memory devices. However, the transition mechanism remains poorly understood. In this study, via in situ transmission electron microscopy with an externally applied DC voltage and nanosecond electrical pulses, for the first time we revealed a reversible structural evolution of Ge2Sb2Te5 thin films from an amorphous state to a single-crystal state via polycrystals as an intermediate state. This transition is different from the traditional understanding of structural changes in Ge2Sb2Te5, i.e., from an amorphous structure to a hexagonal close-packed structure via face-centered cubic as an intermediate structure. In situ observations indicate that this poly-to-single crystal structural transition is caused by coalescence of neighbouring grains induced by an electric field, in which a fast heating/cooling rate is found to be essential. Our study opens a new avenue for the realization of the multi-level operation of phase change materials. [ABSTRACT FROM AUTHOR]

The paleoflow direction of the basal conglomerate of the Changzhougou formation is obtained by the paleocurrent analysis of certain sedimentary structures, and the ancient sedimentary environment of the Qian'an Region is determined by observing the psephicity and gradation of gravel in conglomerate. The results show that the paleoflow direction is from northwest to southwest, and the paleocurrent data manifest a single-peak style in a rose diagram. The average paleoflow direction in the Qian'an region is 265°. The basal conglomerate is of littoral facies, and the sediments of conglomerates are mainly sourced from Shanhaiguan. [ABSTRACT FROM AUTHOR]

Based on monitoring data collected from 2006 to 2009 at the lower reaches of the Tarim River, tempo-spatial variations in groundwater depth and chemistry during an approximately 3-year interval of intermittent water delivery were studied. Results indicate that as the groundwater depth increased at the upper sector of the river's lower reaches from March 2007 to September 2009, so too did the main chemical composition of groundwater. Groundwater depth at the intermediate sector also increased, but major ions in groundwater declined. The groundwater depth at the lower sector started to decrease in August 2008, and the concentrations of main ions in the groundwater generally rose and fell along with the variations in groundwater depth. The groundwater depth and chemistry in the monitoring wells located at a distance from the aqueduct expressed complex changes at different sections. For instance, at the section near the Daxihaizi Reservoir Section B, groundwater depth increased gradually, but chemical composition changed little. In contrast, the groundwater depth of monitoring wells far from the Daxihaizi Reservoir (Section I) decreased and salt content in the groundwater increased. In sectors at a moderate distance from the reservoir, groundwater depth decreased and concentrations of main ions significantly increased. [ABSTRACT FROM AUTHOR]

ABSTRACT Ecohydrological research focuses on the relationship between changes in the hydrological conditions and the response of plant communities to those changes. To save the degraded riparian forests at the lower reaches of the Tarim River, water conveyance embankments (whose goal is to prevent water from overflowing the riverbanks) were constructed mid-stream in order to guide the watercourse down to the river's destination. To investigate and evaluate the influence of these embankments on the Tarim River's riparian forest communities, we prepared three monitoring sections (five others were added later) that included six monitoring wells, six vegetation sample plots and six soil profiles at each section. From 2001 to 2007, data on groundwater depth, vegetation coverage, species diversity, total dissolved solids and concentrations of ions were collected and analysed. The results indicate that groundwater depths gradually increased, total dissolved solids and major ions in groundwater sharply increased and vegetation coverage and species diversity declined. Moreover, at the start of our investigation, the hydrological connection extended more than 1000 m from the embankments; by 2007, however, the region beyond 800 m had become a water and salinity discharging area. On the basis of these findings, the removal of the embankments should be urgently considered to protect the riparian forest ecosystems. Copyright © 2013 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

In order to improve thermal conductivity, energy performance, and combustion performance of the aluminum-containing thermite, nanocarbon materials were added to thermite. Aluminum/molybdenum and trioxide/nanocarbon materials (Al/MoO3/NCM) were fabricated by electrostatic spinning technology. The Al and MoO3 particles of the nAl/MoO3/NCM thermite are much smaller than nitrocellulose (NC); thus, the two components can be better attached to NC fibers. Results on thermal conductivity demonstrated that the addition of NCM can improve the thermal conductivity of Al/MoO3, and the addition of reduced graphene oxide (RGO) has a more significant impact on thermal conductivity. Energy performance analysis results indicated that the energy performance of Al/MoO3/NCM thermite spinning is the best when the value of combustion oxygen equivalent ratio (Φ) is 0.90–1.00. The combustion performance results show that the addition of NCM can significantly increase the combustion rate of thermites, and the addition of RGO improves its combustion rate the most, followed by carbon nanotubes (CNT) and nanoflake graphite (NFG) being the lowest. By changing the shape of the Al/MoO3/NCM charge and the internal composition of the charge, the sensitivity of the agent can be adjusted, and the matching performance and use performance of the electric igniter can be improved. [ABSTRACT FROM AUTHOR]

In this paper, we analysed the monitored data from nine groundwater-monitoring transects in the lower reaches of Tarim River during the five times of stream water deliveries to the river transect where the stream flow ceased. The results showed that the groundwater depth in the lower reaches of Tarim River rose from −9.30 m before the conveyances to −8.17 and −6.50 m after the first and second conveyances, −5.81 and −6.00 m after the third and fourth the conveyance, and −4.73 m after the fifth. The horizontal extent of groundwater recharge was gradually enlarged along both sides of the channel of conveyance, i.e., from 250 m in width after the first conveyance to 1,050 m away from the channel after the fourth delivery. With the rising groundwater level, the concentrations of major anions Cl−, SO and cations Ca2+, Mg2+, Na+, as well as total dissolved solids (TDS) in groundwater underwent a significant change. The spatial variations in groundwater chemistry indicated that the groundwater chemistry at the transect near Daxihaizi Reservoir changed earlier than that farther from it. In the same transect, the chemical variations were earlier in the monitoring well close to watercourse than that farther away from the stream. In general, the concentration of the major ions and TDS at each monitoring well increased remarkably when the water delivery started, and decreased with the continued water delivery, and then increased once again at the end of the study period. Hence, the whole study period may be divided into three stages: the initial stage, the intermediate stage and the later stage. According to the three stages of groundwater chemistry reaction to water delivery and the relationships between groundwater chemical properties and groundwater depths, we educe that under the situation of water delivery, the optimum groundwater depth in the lower reaches of the Tarim River should be −5 m. [ABSTRACT FROM AUTHOR]