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Metal halide perovskite single crystals are promising for hard X‐ray detection, but growth of large‐sized thin single crystals and inhibition of halide ion migration under high bias are challenging. Herein, the preparation of dense stacking of oriented millimeter‐sized perovskite single crystals with capability of large‐area fabrication, controlled thickness, and high ion migration activation energy (Ea)is reported. The oriented growth results in absence of grain boundaries parallel with the substrates, leading to large carrier mobility‐lifetime (µτ) product of 2.7 × 10−3 cm2 V−1, which is comparable to values of many perovskite bulk single crystals. Under low bias, hard X‐ray detectors exhibit high sensitivity of 1.2 × 104 µC Gy−1 cm−2 and low detection limit of 87.5 nGy s−1, which are comparable to those of many single‐crystal hard X‐ray detectors under high bias. Moreover, combination of low bias and high Ea results in weak halide ion migration and small dark current drift of 3.2 × 10−4 nA cm−1 s−1 v−1. Benefited from the superior detector performance, high‐contrast hard X‐ray imaging can be obtained at a low dose rate of 1.26 µGy s−1. The work may promote the application of perovskite hard X‐ray detectors in practical imaging area. [ABSTRACT FROM AUTHOR]

Metal halide perovskite single crystals are emerging candidates for X‐ray detection, however, it is challenging for growth of thickness‐controlled single‐crystal wafer on commercial backplanes, limiting their practical imaging application. Herein, integration of micrometer‐thick methylammonium lead triiodide (MAPbI3) single‐crystal wafer on indium tin oxide (ITO) substrates by methylamine (MA)‐induced interface recrystallization is reported. Through selection of hole transport material with rich functional group, intimate interface contact with low trap density can be achieved, leading to superior carrier transport properties and homogeneous photoresponse. The as‐fabricated X‐ray detectors exhibit high sensitivity of 1.4 × 104 µC Gyair−1 cm−2 and low detection limit of 177 nGyair s−1, which are comparable to previous reports based on free‐standing MAPbI3 bulk crystals. This work provides a feasible strategy for constructing substrate‐integrated single‐crystal perovskite wafers with controlled thickness, which may promote practical imaging application of perovskite X‐ray detectors. [ABSTRACT FROM AUTHOR]

A comprehensive study of the exciton fine structure (EFS) is presented in 2D‐phenethylammonium lead iodide films using magnetic field‐induced polarization of photoluminescence (PL) in both Faraday and Voigt configurations at fields up to 25 Tesla. Three exciton bands are identified in the PL spectrum associated with bound, dark, and bright excitons, respectively. Under a high magnetic field in Faraday/Voigt configuration, large field‐induced circular/linear polarization is observed in the PL band related to the dark exciton, which is magnetically activated. Furthermore, it is found that the dark exciton has an anomalous field‐induced circular polarization, which cannot be explained by the classical Boltzmann distribution of spin‐polarized species. These findings are well explained by an effective mass model that includes exchange terms unique to the monoclinic symmetry as a perturbation of the EFS in the approximate tetragonal symmetry. It is also confirmed that the field‐induced linear polarization is sensitive to the monoclinic exchange term, whereas the field‐induced circular polarization is immune to such term. [ABSTRACT FROM AUTHOR]

Epilepsy is a complex neurological disease characterized by spontaneous recurrent seizures that affect around 1% of the global population. Despite the significant progress in the mechanisms of epileptogenesis, there is still about 60% of cases in which the cause is unknown. Thus, revealing the molecular mechanisms of epileptogenesis will greatly improve the development of epilepsy treatment. Since the comprehensive characterization of amino acids and water‐soluble vitamins is important in understanding the underlying mechanisms of epilepsy or seizures, we developed two liquid chromatography‐tandem mass spectrometry methods to quantify 17 water‐soluble vitamins and 46 amino acids and applied them to our pentylenetetrazole‐induced kindling rat model. All water‐soluble vitamins were detected with a linearity of r > 0.992 and limits of quantitation between 0.1 and 5 ng/ml except for nicotinic acid. For amino acids, the linearities obtained were good with correlation coefficients higher than 0.99, and matrix effects were between 85.3% and 110%. To handle the multidimensional data more effectively, multivariate statistical analysis approaches used in non‐targeted metabolomics were creatively exploited in the visualization, interpretation, and exploration of the results. [ABSTRACT FROM AUTHOR]

Societal Impact Statement: Combining natural and social science approaches to conduct archeological research on wooden cultural relics is important for exploring major aspects of ancient civilizations. The Forbidden City in Beijing, China, is the largest existing wooden palace complex in the world. We examined ancient DNA of imperial wood "Nanmu" specimens taken from representative structural components of the Forbidden City, in order to provide a new perspective on the long‐standing dispute about its species. This allowed us to accurately identify and properly restore these wooden artifacts and improved our understanding of the past interactions between plant distribution, forest resources, and human activities. Summary: Exploring the life styles and production methods of past generations using plant resources can help us to improve our understanding of human civilization. Nanmu, known for its high wood quality, was exclusively used for imperial palace construction in the 15th–19th centuries in China, yet its species has been a subject of long‐standing debate.Here, we revisit this unresolved problem, using morphology and ancient DNA (aDNA) to analyze 21 centuries‐old Nanmu specimens sampled from representative palaces of the Forbidden City.Cytochemical staining demonstrated that endogenous aDNA sporadically occurs in the wood ray parenchyma cells of Nanmu specimens. High‐quality plastid genomes were retrieved from archeological woods for the first time via an aDNA capture method, with 90%–100% coverage (137,663–152,805 bp) and sequence depths of 27.05‐ to 1409.94‐fold. Utilizing these ancient genomes, our results demonstrate that Phoebe zhennan and Phoebehui are most likely the main species of Nanmu in the Forbidden City.This finding diverges from the prevailing view that Nanmu encompasses woods from the whole genus Phoebe and even its close relative Machilus. It also shows that stringent criteria were used when selecting construction materials for the Forbidden City. By combining morphological traits with aDNA analyses, we provide a new solution for identifying the species of timber used for ancient architecture, and we increase our understanding of the way in which forest resources were recognized and utilized by our ancestors despite the lack of a plant taxonomic framework in ancient times. [ABSTRACT FROM AUTHOR]

The eco‐friendly properties enable two‐dimensional (2D) Cu‐based perovskites as ideal candidates for next‐generation optoelectronics, but practical application is limited by low photoelectric conversion efficiency because of poor carrier transport abilities. Here, we report enhanced structural stability of 2D CuBr4 perovskites under compression up to 30 GPa, without obvious volume collapse or structural amorphization, by inserting organic C6H5CH2NH3 (PMA) groups between layers. The band gap value of (PMA)2CuBr4 can be effectively tuned from 1.8 to 1.47 eV by employing external pressures, leading to a broadened absorption range of 400–800 nm. Notably, we successfully detected photoconductivity of the photoresponse at pressures from 10 to 40 GPa; the maximum value of 5×10−3 S cm−1 is observed at 28 GPa, indicating potential applications for high performance photovoltaic candidates under extreme conditions. [ABSTRACT FROM AUTHOR]

The eco‐friendly properties enable two‐dimensional (2D) Cu‐based perovskites as ideal candidates for next‐generation optoelectronics, but practical application is limited by low photoelectric conversion efficiency because of poor carrier transport abilities. Here, we report enhanced structural stability of 2D CuBr4 perovskites under compression up to 30 GPa, without obvious volume collapse or structural amorphization, by inserting organic C6H5CH2NH3 (PMA) groups between layers. The band gap value of (PMA)2CuBr4 can be effectively tuned from 1.8 to 1.47 eV by employing external pressures, leading to a broadened absorption range of 400–800 nm. Notably, we successfully detected photoconductivity of the photoresponse at pressures from 10 to 40 GPa; the maximum value of 5×10−3 S cm−1 is observed at 28 GPa, indicating potential applications for high performance photovoltaic candidates under extreme conditions. [ABSTRACT FROM AUTHOR]

The eco‐friendly properties enable two‐dimensional (2D) Cu‐based perovskites as ideal candidates for next‐generation optoelectronics, but practical application is limited by low photoelectric conversion efficiency because of poor carrier transport abilities. Here, we report enhanced structural stability of 2D CuBr4 perovskites under compression up to 30 GPa, without obvious volume collapse or structural amorphization, by inserting organic C6H5CH2NH3 (PMA) groups between layers. The band gap value of (PMA)2CuBr4 can be effectively tuned from 1.8 to 1.47 eV by employing external pressures, leading to a broadened absorption range of 400–800 nm. Notably, we successfully detected photoconductivity of the photoresponse at pressures from 10 to 40 GPa; the maximum value of 5×10−3 S cm−1 is observed at 28 GPa, indicating potential applications for high performance photovoltaic candidates under extreme conditions. [ABSTRACT FROM AUTHOR]

The eco‐friendly properties enable two‐dimensional (2D) Cu‐based perovskites as ideal candidates for next‐generation optoelectronics, but practical application is limited by low photoelectric conversion efficiency because of poor carrier transport abilities. Here, we report enhanced structural stability of 2D CuBr4 perovskites under compression up to 30 GPa, without obvious volume collapse or structural amorphization, by inserting organic C6H5CH2NH3 (PMA) groups between layers. The band gap value of (PMA)2CuBr4 can be effectively tuned from 1.8 to 1.47 eV by employing external pressures, leading to a broadened absorption range of 400–800 nm. Notably, we successfully detected photoconductivity of the photoresponse at pressures from 10 to 40 GPa; the maximum value of 5×10−3 S cm−1 is observed at 28 GPa, indicating potential applications for high performance photovoltaic candidates under extreme conditions. [ABSTRACT FROM AUTHOR]

Self‐powered perovskite X‐ray detectors have drawn increasing attention due to the merits of low noise, low power consumption as well as high portability and adaptability. However, the active layer thickness is usually compromised by the small carrier diffusion length, which leads to inefficient X‐ray attenuation and hence low sensitivity of the detectors. Herein, self‐powered and highly sensitive single‐crystal perovskite X‐ray detectors are achieved by finely controlling the crystal thickness and optimizing their carrier transport properties. Perovskite single crystals with thickness of around 800 µm are grown by a two‐step crystal growth process to realize the full attenuation of hard X‐ray with the energy of 80 keV. And the incorporation of formamidinium (FA) (FA = CH(NH2)2+) cation into methylammonium lead triiodide (MAPbI3) (MA = CH3NH3+) increases the mobility‐lifetime (µτ) product of the single crystals by nearly one order of magnitude, leading to a record X‐ray detection sensitivity of 8.7 × 104 µC Gyair−1 cm−2 under zero bias. Moreover, the eliminated external bias and reduced trap density weaken the field‐driven ion migration effect, and therefore result in a low detection limit of 27.7 nGy s−1. This work represents an effective way to achieve self‐powered perovskite X‐ray detectors with both high sensitivity and low detection limit. [ABSTRACT FROM AUTHOR]

Perovskite single crystals have recently been regarded as emerging candidates for photovoltaic application due to their improved optoelectronic properties and stability compared to their polycrystalline counterparts. However, high interface and bulk trap density in micrometer‐thick thin single crystals strengthen unfavorable nonradiative recombination, leading to large open‐circuit voltage (VOC) and energy loss. Herein, hydrophobic poly(3‐hexylthiophene) (P3HT) molecule is incorporated into a hole transport layer to interact with undercoordinated Pb2+ and promote ion diffusion in a confined space, resulting in higher‐quality thin single crystals with reduced interface and bulk defect density, suppressed nonradiative recombination, accelerated charge transport, and extraction. As a result, a remarkably enhanced VOC of up to 1.13 V and efficiency of 22.1% are achieved, which are both the highest values for MAPbI3 single‐crystal solar cells. Moreover, the reduced defect density and suppressed carrier recombination lead to superior weak light response of the single‐crystal solar cells after incorporation of P3HT, and an indoor photovoltaic efficiency of 39.2% at 1000 lux irradiation is obtained. [ABSTRACT FROM AUTHOR]

Bi2Fe4O9/Ag3PO4 (BFO/APO) composites as a kind of new material were successfully prepared through the hydrothermal‐precipitation method and employed for degrading 17α‐ethynyl estradiol (EE2). Upon illumination, the total removal efficiency of EE2 reached 98.68 % and the reaction rate constant K value of 1 : 6 BFO/APO (0.05111 min−1) was respectively 7, 5 and 55 times that of BFO (0.01074 min−1), APO (0.007260 min−1) and conventional photocatalysis (9.38×10−4 min−1). The combination with BFO also effectively prevented the occurrence of APO photo corrosion reactions. According to the capture experiments,.O2−, holes and.OH are considered major or minor important respectively to the photocatalytic reaction. This work provides a new insight in construct the direct Z‐scheme photocatalyst for EE2 degradation. [ABSTRACT FROM AUTHOR]

Background: The role of sine oculis homeobox 4 (SIX4) has been found in some malignant tumors. However, there have been few studies on the function of SIX4 in esophageal squamous cell carcinoma (ESCC). This study aimed to explore the regulatory mechanism of SIX4 in ESCC. Methods: RT‐qPCR and Western blot analysis were used to measure mRNA and protein expression. The function of SIX4 was investigated using CCK‐8, colony formation, flow cytometry, wound healing and transwell assays. A mouse xenograft tumor assay was designed to perform in vivo experiments. Results: SIX4 was upregulated in ESCC and indicated poor clinical outcomes in ESCC patients. Functionally, knockdown of SIX4 inhibited cell proliferation and induced apoptosis in ESCC. In addition, the silencing of SIX4 inhibited cell migration, invasion and EMT in ESCC. More importantly, upregulation of SIX4 could activate the PI3K/AKT pathway in ESCC cells and promote tumor growth in vivo. Conclusions: Upregulation of SIX4 indicates poor clinical outcomes in ESCC patients and promotes tumor growth and cell metastasis in ESCC. [ABSTRACT FROM AUTHOR]

The exceptional structural tunability of organic metal halides endows them with fascinating electronic and photophysical properties, providing much scope for applications. In this work, single crystals of the organic metal halide (C4H9NH3)2MnI4 are found to show reversible thermo‐induced luminescent chromism within a wide temperature range. The (C4H9NH3)2MnI4 single crystal exhibits two emission peaks at 550 and 672 nm, which are assigned to a d–d transition of Mn2+‐centered tetrahedra and self‐trapped excitons, respectively. The temperature‐dependent emission color change is attributed to the thermo‐induced trapping and detrapping process of the self‐trapped exciton. (C4H9NH3)2MnI4 exhibits a maximum photoluminescence quantum efficiency of up to 68 % at 70 °C. The disclosed interacted photoluminescence decay mechanisms may prove useful for the further design of organic metal halides for optical thermometry. [ABSTRACT FROM AUTHOR]

Sweetcane (Erianthus arundinaceus [Retzius] Jeswiet) is an ecologically dominant warm‐season perennial grass native to southern China. It traditionally plays an important role in sugarcane breeding due to its excellent biological traits and genetic relatedness to sugarcane. Recent studies have shown that sweetcane has a great potential in bioenergy and environmental remediation. The objective of this paper is to review the current research on sweetcane biology, phenology, biogeography, agronomy, and conversion technology, in order to explore its development as a bioenergy crop with environmental remediation potential. Sweetcane is resistant to a variety of stressors and can adapt to different growth environments. It can be used for ecological restoration, soil and water conservation, contaminated land repairing, nonpoint source pollutants barriers in buffer strips along surface waters, and as an ornamental and remediation plant on roadsides and in wetlands. Sweetcane exhibits higher biomass yield, calorific value and cellulose content than other bioenergy crops under the same growth conditions, thereby indicating its superior potential in second‐generation biofuel production. However, research on sweetcane as a bioenergy plant is still in its infancy. More works need be conducted on breeding, cultivation, genetic transformation, and energy conversion technologies. Sweetcane is an ecologically dominant warm‐season perennial grass with excellent biological traits and genetic relatedness to sugarcane. It not only plays an important role in sugarcane breeding, but also has great potential in environmental remediation and as a biofuel feedstock. It can be planted on many types of marginal land in southern China for biofuel feedstock, environmental remediation, or both. More works need be conducted on its breeding, cultivation, genetic transformation, and energy conversion technologies. [ABSTRACT FROM AUTHOR]

Summary of main observation and conclusion: Selective oxidative C—H sulfenylation of imidazopyridine heterocycles is achieved using an undivided electrolytic cell. The reaction avoids the use of stoichiometric amount of external chemical oxidant and produces hydrogen gas as the only byproduct. Both aryl and aliphatic thiols demonstrate good reactivity for C—S bond formation. This work describes an exogenous‐oxidant‐free C—H sulfenylation of imidazopyridines using an electrochemical oxidative protocol. [ABSTRACT FROM AUTHOR]

ABSTRACT In order to further decrease the cost and enhance the durability of sulfonated poly(ether ether ketone) membrane for vanadium redox flow battery, a super thin (40 μm) polytetrafluoroethylene (PTFE)/SPEEK (PS) membrane is prepared. The physico-chemical properties and single cell performance of PS membranes prepared with different casting solvents including NMP ( N-methyl-2-pyrrolidone), DMF ( N,N′-dimethylformamide), and DMAc ( N,N′-dimethylacetamide) have been investigated. Results show that the energy efficiency of VRB with PS/DMF can reach up to 91.2% at the current density of 40 mA cm−2, which is 11.1% and 6.4% higher than that of the commercial Nafion 212 and pristine SPEEK membrane, respectively. In addition, charge-discharge test over 150 times proves that the PS/DMF membrane possesses high stability and thus it is suitable for VRB application. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016, 133, 43593. [ABSTRACT FROM AUTHOR]

The eco‐friendly properties enable two‐dimensional (2D) Cu‐based perovskites as ideal candidates for next‐generation optoelectronics, but practical application is limited by low photoelectric conversion efficiency because of poor carrier transport abilities. Here, we report enhanced structural stability of 2D CuBr4 perovskites under compression up to 30 GPa, without obvious volume collapse or structural amorphization, by inserting organic C6H5CH2NH3 (PMA) groups between layers. The band gap value of (PMA)2CuBr4 can be effectively tuned from 1.8 to 1.47 eV by employing external pressures, leading to a broadened absorption range of 400–800 nm. Notably, we successfully detected photoconductivity of the photoresponse at pressures from 10 to 40 GPa; the maximum value of 5×10−3 S cm−1 is observed at 28 GPa, indicating potential applications for high performance photovoltaic candidates under extreme conditions. [ABSTRACT FROM AUTHOR]

All‐inorganic Cd‐based metal halide is widely studied and applied in the field of optoelectronics due to its superior stability, diverse phase structure, and unique photoelectric properties. However, all‐inorganic 0D Cd‐based metal halide is not widely studied due to their extreme synthesis conditions. In this paper, a simple mild solution method is devised to successfully synthesize 0D Cs3CdBr5 by manipulating the crystal growth kinetics. Simultaneously, the influence of the doping element Mn on the transition matrix and the optical properties are investigated. By doping with an appropriate concentration of Mn2+, a green emission (520 nm) with photoluminescence quantum yield (PLQY) as high as 97.39% is obtained. Benefiting from near‐unity PLQY and the excellent optical properties, the white emitting light‐emitting diodes (WLEDs) with Cs3CdBr5:20%Mn as green phosphor exhibit warm white light emission with color rendering index (CRI) of 91 and correlated color temperature (CCT) of 4108 K. In addition, Cs3CdBr5:20%Mn also demonstrates excellent X‐ray scintillation properties with a low detection limit of 32.83 nGyair·s−1. The results show that Cs3CdBr5:Mn is not only a promising candidate for solid‐state lighting but also a promising candidate for low‐dose high‐resolution X‐ray imaging. [ABSTRACT FROM AUTHOR]

Objective: To evaluate Chinese healthcare providers' knowledge regarding medical abortion, to understand provider preferences for abortion methods, and to investigate the role of remuneration on providers' decision making.Methods: Between November 2009 and May 2010, 658 abortion service providers from family-planning service centers and hospitals in Shenzhen and Henan, China, were surveyed via self-administered questionnaires.Results: The knowledge score (out of a maximum of 32) regarding medical abortion was 16-20 for 60.9% of the providers; 20.4% of the providers preferred medical abortion to surgical abortion, whereas 35.0% preferred surgical abortion. Overall, 72.2% of providers stated that they did not receive any commission for providing medical abortion or surgical abortion.Conclusion: Most healthcare providers believed that surgical abortion was preferable to medical abortion. Efforts should be made to overcome the perceived disadvantages of medical abortion. [ABSTRACT FROM AUTHOR]

Abstract: Objective: To investigate providers'' knowledge and attitudes about medical abortion (MA) and their views regarding the main challenges to expanding the use of MA in urban and rural areas in China. Methods: A total of 658 abortion providers were surveyed from November 7, 2009, to May 29, 2010. Results: The providers'' knowledge about MA was relatively poor, and most thought the risks of severe complications of MA were much higher than they are. Urban nonphysician providers were the least informed about MA. Most providers thought that the main challenges to an expanded use of MA were its lesser effectiveness in comparison to surgical abortion and women''s lack of knowledge about it. In rural areas many providers thought that deficiencies of clinics, such as limited bed space and inadequate toilets and washing facilities, also posed serious obstacles to expanding MA use. Conclusion: Abortion providers, especially urban nonphysician providers, need refresher training to strengthen their knowledge of the approved protocol for providing MA in China, and also of the indications, contraindications, and safety and efficacy of the method. Deficiencies at abortion facilities should be addressed as well, and they are more numerous in rural areas. [Copyright &y& Elsevier]