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Atmospheric escape is a central issue in understanding how Mars lost the habitability and it is critically controlled by the link between the atmosphere and the interplanetary space, i.e. the ionosphere. The predominant driver of the Martian ionospheric variability is the solar extreme ultraviolet radiation. To date, how the ionospheric electrons respond to this radiation has been well investigated, but the responses of various ion species are to be understood. Based on a multi-instrument data set from the Mars Atmosphere and Volatile Evolution, we report direct observations of quasi-periodical variations of photoelectrons and ions, with a common period of ≈27.2 d and almost in exact phase with the solar rotation. These diverse variations present remarkably different amplitudes. The ion density variation has a much larger amplitude than the solar flux variation and the electron density variation has a smaller amplitude. For comparison, the amplitude of the photoelectron intensity variation is nearly identical to that of the solar flux variation. The species-dependent solar rotation effects provide a good diagnostic of the upper atmospheric and ionospheric chemistry, urging reconsiderations of the solar-driven composition and variability of any planetary ionosphere.

Joint replacement surgery is one of the orthopedic surgeries with high successful rates; however, wear debris generated from prostheses can ultimately lead to periprosthetic osteolysis and failure of the implant. The implant-derived particulate debris such as ultrahigh molecular weight polyethylene (UHMWPE) can initiate the local immune response and recruit monocytic cells to phagocytose particles for generating reactive oxygen species (ROS). ROS induces osteoclastogenesis and macrophages to secrete cytokines which ultimately promote the development of osteolysis. In this work, we develop the few-layered Nb2C (FNC) as an antioxidant which possesses the feature of decreasing the production of cytokines and inhibiting osteoclastogenesis by its ROS adsorption. Moreover, local injection of FNC attenuates the UHMWPE-induced osteolysis in a mouse calvarial model. In sum, our results suggest that FNC can be used for treating osteolytic bone disease caused by excessive osteoclastogenesis., Graphical abstract Image 1, Highlights • Few-layered Nb2C (FNC) was synthesized by chemical exfoliation from bulk Nb2C (BNC) and showed an outstanding elimination of ROS on the basis of density functional theory (DFT) and inhibition effect of oxidative stress in vitro. • Osteoxlastogenesis was driven by reactive oxygen species (ROS), controlling osteoclasts differentiation in the early stage. • FNC inhibited osteoclastogenesis via scavenging ROS and dampening related signal pathway. • UHMWPE-induced osteolysis was attenuated by FNC therapy.

The λ-shape dielectric anomaly follows the Curie–Weiss law with a 105.8-fold change at a frequency of 500 Hz. The spontaneous polarization of TATC can reach 1.4 μC cm−2. The TATC crystal has a 4.03 eV indirect bandgap.

As total mesorectal excision (TME) for rectal cancer is widely carried out in China, lateral ligament of rectum, as an important anatomical structure of the lateral rectum with certain anatomical value and clinical significance, has been the focus of attention. In this paper, by comparing and analyzing the characteristics about ligaments of the abdomen and pelvis, reviewing the membrane anatomy and the theory of primitive gut rotation, and combining clinical observations and histological studies, the author came to a conclusion that lateral ligament of rectum does not exist, but is only a relatively dense space on the rectal side accompanied by numerous tiny nerve plexuses and small blood vessels penetrating through it.随着全直肠系膜切除术在我国的广泛开展，直肠侧韧带作为直肠侧的一个重要解剖结构，具有一定的解剖价值和临床意义，一直是人们关注的焦点。本文通过对比分析腹盆韧带的特点，回顾膜解剖学和原肠旋转理论，结合临床观察和组织学研究，得出我们的结论：直肠侧韧带并不存在，它只是直肠侧的一个相对致密的间隙，并伴有无数细小的神经丛和小血管穿透其中。.

Due to the lack of effective early diagnosis and treatment, gallbladder cancer(GBC) remains a malignant tumor with extremely high malignancy and poor prognosis. Therefore, high quality studies are required to break through the bottleneck in GBC diagnosis and treatment. This article reviewed the domestic and foreign GBC research published in 2021, presenting a comprehensive summary of the important advances in the field of clinical diagnosis and treatment. Latest epidemiological data and risk factors, emerging diagnostic methods of peripheral blood laboratory tests and imaging, new pathologic classification system, hot topics and controversies of surgical treatment as well as the dynamics of systemic treatment of GBC are reviewed in the article. The present findings may contribute to a more efficient means of diagnosis and treatment for GBC and hold the promise of improved outcomes for patients with GBC.胆囊癌的恶性程度极高，缺乏早期诊断方法和有效治疗手段，亟需高质量研究突破诊疗瓶颈。本文回顾了2021年国内外发表的胆囊癌研究相关文献，对临床诊疗领域的重要进展进行综述，详细介绍了胆囊癌最新流行病学数据及危险因素、新兴的外周血实验室检查和影像学诊断方法、病理学类型新分类、外科治疗的热点与争议及系统性综合治疗动态。这些研究结果有助于探索更有效的胆囊癌诊治方法，为改善胆囊癌患者的预后带来希望。.

Context. Characterizing the response of the upper Martian atmosphere to solar flares could provide important clues as to the climate evolution of the red planet in the early Solar System, when the extreme ultraviolet and soft X-ray radiation was substantially higher than the present-day level and when these events occurred more frequently. A critical process herein is the Martian atmospheric escape in the form of atomic C and N, as mainly driven by CO2/CO and N2 dissociation. Aims. This study is devoted to evaluating how these escape rates varied on the dayside of Mars during the X8.2 solar flare on 10 September 2017. Methods. The background Martian atmospheric structures, before, during, and after the flare, are constructed from the Neutral Gas and Ion Mass Spectrometer measurements made on board the Mars Atmosphere and Volatile Evolution spacecraft, from which the hot C and N production rate profiles via different photon and photoelectron impact channels and on different flare stages are obtained. They are combined with the respective escape probability profiles computed using a test particle Monte Carlo approach to derive the atomic C and N escape rates on the dayside of Mars. Results. Our calculations indicate that the pre-flare C and N escape rates are (1.3−1.4) × 1024 s−1 over the dayside of Mars. During the event, we find a modest decrease in the C escape rate of 8% about 1 h after the flare peak, followed by a recovery to the pre-flare level several hours later. However, an opposite trend is found for the N escape rate during the same period, which shows an increase of 20% followed by a recovery to the pre-flare level. Conclusions. The distinction between C and N in terms of the variation in the escape rate during the solar flare reflects the competition between two flare-induced effects: enhanced hot atom production via dissociation and enhanced collisional hindrance due to atmospheric expansion.

La0.5-xDyxCa0.5-ySryMnO3 (x=0, 0.05, 0.08, 0.1, 0.14, 0.16, 0.2) polycrystalline samples were prepared by high-temperature solid-state reaction. The A-site disordering is increased with the doping concentration x, and meanwhile the average ionic radius of A-site is kept constant. X-ray diffraction and Raman spectroscopy were combined to investigate the microstructural distortion of MnO6 octahedron. Results show that the rotational vibration (RV) is the dominant distortion mode. With the A-site disordering increasing, RV mode is obviously hardened, and the Jahn-Teller distortion is enhanced. Properties investigation shows that the insulation is strengthened because of FM double exchange effect suppressed with A-site disordering increasing, and the magnetoresistance effect is weakened. A relatively significant magnetoresistance effect was observed in the low temperature region for the high-doped concentration sample, which may be related to the strong magnetic moment of Dy3+.

In general, it is hard to grow large single crystals with a one-dimensional chain structure due to the preferred growth direction and chain breakage. Most reported one-dimensional lead iodine chain single crystals can grow long, but they are difficult to grow thick. Here, we demonstrate for the first time the growth of 2 mm × 4 mm × 8 mm sized single crystal one dimensional organic lead iodine perovskite – DMAPbI3 ((CH3)2NH2PbI3). Benzylamine addition to the solution may help to dissolve crystals with high defect concentrations so that the crystal can grow larger. Through the measurement on the large single crystal, we found that DMAPbI3 is ferroelectric below 260 K, and the dielectric constant of DMAPbI3 at various frequencies at room temperature is as high as more than 100. Blue photoluminescence centered at 2.6 eV was reported. The ferroelectricity of DMAPbI3 may be used to design more stable and efficient organometal halide perovskite solar cells and photoelectric devices.

Ferroelectrics are widely applied in modern industrial production due to their fascinating physical properties. New findings on organic ferroelectric materials have gained the attention of researchers because they have flexible designs and are easy to produce. Here, we report on an overlooked compound, trimethylammonium bromide ((CH3)3NHBr), that demonstrates ferroelectricity just below room temperature. The compound undergoes a first-order paraelectric–ferroelectric phase transition at the Curie temperature (Tc) around 286 K, accompanied by significant changes in the structural, thermal and electrical properties. The space group of the compound transforms from P21 to P21/m at the Curie temperature Tc. The remnant polarization Pr is about 0.4 μC cm−2 at 230 K and 0.25 μC cm−2 at 243 K. This finding reveals a new pathway to design and synthesize molecular ferroelectrics.

Organic-inorganic hybrid ferroelectrics (OIHFs) have fueled enormous interest benefiting from their less environmental pollution, performance-tailored functionality, low product costs as well as tunability of structures. However, the lack of material synthesis approaches and diverse targeted molecular design is a stumbling block for designing novel OIHFs rationally. Here, we report a unique organic-inorganic hybrid ferroelectric (3,3-difluoropyrrolidine)2CdCl4 1 and another novel nonferroelectric crystal (3,3-difluoropyrrolidine)2Cd2Cl6 2 by changing various crystallization solvents. Significantly, 1 presents a ferroelectric phase transition behavior at ∼367 K, and the distinct symmetry breaking, i.e., mmmFm, sets up a biaxial ferroelectric with four equivalent directions of polarization, which has a Pr ∼ 0.77 μC/cm2. Systematic studies prove that ferroelectricity can be ascribed to the synergistic effects of the distortion of the inorganic anion skeleton and the ordering of organic cations. This work reveals the potential of constructing novel ferroelectrics based on the solvent selective effect and pyrrolidinium as organic cations.

Monolayer molybdenum disulfide (MoS

The double-wave method is widely used in ferroelectric measurements to eliminate the effects of conductance and capacitance components while preserving the ferroelectric domain contribution. However, in polycrystalline ferroelectric material, the assumption of the evolution of domains by the double-wave method no longer applies due to the domain back switch of de-field, and the domain contribution calculated by the current subtraction method is also problematic. Therefore, we proposed a new method to calculate the charge contribution of conductance and eliminate the conductance interference in the hysteresis loop. Finally, the feasibility of this new method is verified in many typical polycrystalline ferroelectric materials. This work provides a path for the study of ferroelectric properties of some high conductivity materials.

SrTiO

Graphitic carbon nitride (g-C3N4) is a two-dimensional (2D) photocatalyst, but it appears a mediocre catalytic property due to the recombination of charge carriers. Constructing heterojunctions can boost the separation and suppress the recombination of photo-generated electron–hole pairs. For the conventional Type-II heterojunction, the oxidation ability is significantly reduced due to the decreasing of band gap. We try to maintain its oxidation capacity and promote the artificial bandgap by tailoring a Z-scheme heterojunction through interface engineering. Herein, we grafted different proportions of YMnO3 3D-nanoparticles onto g-C3N4 2D-nanosheets. This special 2D/3D mixed-dimensional nanocomposite exhibits efficient charge carrier transport performance according to the electrochemistry and photocurrent measurement. The outstanding photocatalytic oxidation ability can be verified by the rate of Rhodamine B degradation, which is 3.8 and 2.3 times of YMnO3 and g-C3N4, respectively. Theoretical calculation, active group capture experiments and electron spin resonance indicate the energy band position and the reactive groups (superoxide radicals and holes). The optimized g-C3N4/YMnO3 heterojunction utilizes the interfacial synergistic effect to achieve a composition of vigorous oxidizing ability and outstanding visible light harvesting. This work will pave a promising access for mechanism and interface engineering of other g-C3N4-based Z-scheme heterojunctions.

The ceramics of Sr3-xBaxSn2O7 (0 ≤ x ≤ 0.6) were synthesized by solid-state reaction method. The lattice constants of Sr3-xBaxSn2O7 increase with increasing of Ba doping. With increasing of the Ba2+ concentration from x = 0 to x = 0.2, the phase transition temperature reduces by 73 K. The vibration modes related to the phase transitions are strongly related to the tilting and rotation of SnO6 octahedra. The doping of Ba significantly aggravates the anharmonic effect and increases the Raman activity of the vibration mode A 2 ( 5 ) , and reduces the phonon lifetime and the Raman activity of the vibration mode A 1 17 .

A typical multiferroic manganese oxide of HoMnO3 was partially substituted by Fe at Mn site. Orthogonal crystalline phase of HoMn1−xFexO3 was synthesized at normal pressure. This finding has changed the conventional method of synthesizing orthogonal crystalline phase of rare-earth manganese oxides under high-temperature and high-pressure. The doping of iron ions suppresses the formation of hexagonal phase as revealed from X-ray diffraction, Morphology analysis, Raman spectrum and X-ray photoelectron spectroscopy. The doping of Fe3+ into HoMnO3 causes changes in the space group of the sample and ferroelectricity at room temperature. There are two phases with a ferroelectric space group of $${P6}_{3}cm$$ and a paraelectric one of Pnma coexisted in Ho $${\text{Mn}}_{1-x}{Fe}_{x}{O}_{3}$$ polycrystalline with x 0.15, the phase with $${P6}_{3}cm$$ space group disappears, and samples have only one crystalline phase Pnma. We found that the sample remained ferroelectricity at room temperature in the process of changing the doping concentration. The ferroelectric property disappears until it completely changed to the orthogonal phase. The synthesis of orthogonal HoMnO3 at normal pressure has not been previously reported and potentially open up abroad research and application prospects.

Advances in creating metal oxide heterostructures have received a great deal of attention because novel properties like two-dimensional electron gas (2DEG), which was first found in LaAlO3/SrTiO3 interface, while does not exist in the bulk materials. To extend the study on 2DEG, we investigate the electronic property of interesting nonpolar/nonpolar LiAlO2/SrTiO3 heterostructure (also perovskite/nonperovskite oxide heterostructure), with and without oxygen vacancies by first-principles calculations. Two types of interfaces, SrO/LiAlO2 and TiO2/LiAlO2 interfaces, were modeled with the stable stacking configurations. Oxygen vacancies at LiAlO2/SrTiO3 interface induce the carriers in this system. there is no 2DEG behavior detected. Our results show that three-dimensional transport behavior occurs in the perovskite/non-perovskite oxide interface.

Molecule-based ferroelectrics are a class of highly desirable intelligent materials for their highly variable physical properties, easy and environmentally friendly processing, especial light weight and mechanical flexibility. 4-Aminopyridinium Perchlorate (APP), used to be known as a pyroelectric below 243 K, is first discovered to be a new molecular ferroelectric in this work, which has a perfect electric hysteresis loops with a large spontaneous polarization of 1.0 μC/cm2 and a small coercive field of 0.67 kV/cm below 246 K. Owing to the dramatic changes of the protonated cations and order–disorder of anions, the crystal symmetry of APP transforms from P21/c to P21 in this first-order phase transition, which is revealed by other measurements, such as differential scanning calorimetry, heat capacity, dielectric anomalies and Raman spectrum.

Molecular ferroelectrics are a kind of functional materials that have large application prospects. Comparing with the traditional inorganic ferroelectrics, they have some advantages, such as easy design, environment-friendliness, nontoxicity, and flexibility. In this study, a new molecular ferroelectric pyridin-2-ylmethanaminium perchlorate was discovered, which undergoes a ferroelectric phase transition at around 264.8 K. The spontaneous polarization reaches 0.22 μC cm−2, and the coercive fields are as small as 1.1 kV cm−1 at 202 K. The single-crystal X-ray diffraction analysis reveals that the space group transforms from a polar space group of P21 at 173 K to a centrosymmetric space group of P21/c at 293 K. By analyzing the crystal structure changes below and above the phase transition temperature, it can be concluded that the phase transition is induced by the disorder of perchlorate. Its ferroelectricity was confirmed by the measurements of differential scanning calorimetry, dielectric and hysteresis loop.

This study aims to explore the expression pattern and clinical significance of circ_001680 in gastric carcinoma (GC) process.Circ_001680 levels in 40 pairs of GC and paracancerous ones were detected by quantitative real-time polymerase chain reaction (qRT-PCR). The relationship between circ_001680 and GC clinicopathological parameters was analyzed. AGS and SGC-7901 cells were used for constructing circ_001680 knockdown models by shRNA transfection. Proliferative and metastatic abilities in GC cells with circ_001680 knockdown were examined by cell counting kit-8 (CCK-8) and transwell assay, respectively. Dual-Luciferase reporter assay was conducted to clarify the interaction between circ_001680 and MAP2. Their co-regulation on GC process was detected through rescue experiments.Circ_001680 was highly expressed in GC tissues and cell lines. High level of circ_001680 predicted high incidences of lymphatic and distant metastasis, and poor prognosis in GC patients. Knockdown of circ_001680 suppressed proliferative and metastatic abilities in AGS and SGC-7901 cells. MAP2 was the target gene binding circ_001680, which was lowly expressed in GC. In addition, MAP2 was negatively correlated to circ_001680. Knockdown of MAP2 could abolish the suppressed proliferative and metastatic abilities in GC cells with circ_001680 knockdown.Circ_001680 is highly expressed in GC tissues and closely related to metastasis and prognosis in GC patients, which promotes the proliferative and metastatic abilities in GC cells by negatively interacting with MAP2.

Although the dental lamina of permanent teeth in human being has been developed as early as the embryo stage, the replacement of the deciduous teeth by permanent teeth does not take place untill the age of 6 to 12 years old. The molecular mechanism of the initiation of permanent teeth is still unclear. The rodent species are usually used for the tooth development research in the past. However, this animal model is not suitable for the tooth replacement study because of the absence of tooth replacement in rodents. After 10 years of efforts, our team has established the animal model of miniature pig for tooth replacement research. Using this model, we firstly defined the spatiotemporal pattern of teeth replacement. In the further mechanism research, results showed that the growing rate of the deciduous teeth was faster than that of the surrounding alveolar bone, and biomechanical stress inside mandible was generated due to the fast growth of deciduous teeth. The stress might up-regulate the signal of Runt-related transcription factor 2 (RUNX2)-Wnt pathway in the mesenchyme between the deciduous and permanent teeth, sustain the successional dental lamina at the resting stage and inhibit the development of permanent teeth. A similar expression pattern was also found in the mesenchyme between the deciduous and permanent teeth in human. Our findings demonstrated that the eruption of deciduous tooth released the stress inside mandible, thus induced the "Wnt translocation" from the mesenchyme into the epithelium of permanent counterpart and therefore initiated the development of permanent teeth. The underlying mechanism of the replacement of deciduous teeth by permanent teeth is the regulation of biomechanical stress throughout the initiation process. Based on the findings, we proposed the theory of "biomechanical stress regulation of the tooth replacement" . The replacement pattern and regulatory mechanism provide a scientific foundation for the organ development and regeneration by regulating the biomechanical stress and Wnt pathway in the future.尽管人类替换恒牙的牙板在胚胎时就已经形成，但直到6~12岁期间才进行乳恒牙替换，这种替换恒牙时空启动的调控分子机制一直不清楚。因以往牙发育研究多以啮齿类动物为研究模型，没有乳恒牙替换，无法进行人类乳恒牙替换相关研究。本课题组经过10余年努力，创建小型猪牙发育研究平台，利用此大型动物模型开展乳恒牙发育替换模式和机制研究。明确了小型猪乳恒牙替换的时空发育模式，进一步的牙替换机制研究表明，乳牙发育速率快于颌骨产生的组织内生物应力；该应力上调乳恒牙之间间充质内Runt相关转录因子2（Runt-related transcription factor 2，RUNX2）-Wnt信号，抑制替换恒牙牙板发育，使替换恒牙牙板较长时间处于相对静止状态；该分子表达模式在人乳恒牙牙胚之间间充质内得到验证；乳牙萌出释放组织内应力引起Wnt信号从间充质转位至恒牙上皮启动恒牙发育。由此发现了组织内应力调控乳恒牙替换的机制，提出"组织内应力调控牙齿替换"学说。乳恒牙替换模式及调控机制的发现为通过调控生物力学及Wnt通路实现器官发育与再生提供了科学基础。.

For materials near the phase boundary between weak and strong topological insulators (TIs), their band topology depends on the band alignment, with the inverted (normal) band corresponding to the strong (weak) TI phase. Here, taking the anisotropic transition-metal pentatelluride ZrTe_{5} as an example, we show that the band inversion manifests itself as a second extremum (band gap) in the layer stacking direction, which can be probed experimentally via magnetoinfrared spectroscopy. Specifically, we find that the band anisotropy of ZrTe_{5} features a slow dispersion in the layer stacking direction, along with an additional set of optical transitions from a band gap next to the Brillouin zone center. Our work identifies ZrTe_{5} as a strong TI at liquid helium temperature and provides a new perspective in determining band inversion in layered topological materials.

The emerging two-dimensional (2D) materials such as graphene have opened the door to industrial applications. Here, we consider the oxide perovskite monolayer of SrTiO

We report here a simple in-situ methodology to grow CdS nanobelts on Cd foil via annealing under H2S/N2 flux. The maximum size of CdS nanobelt reaches 4 μm in width and 200 μm in length. CdS nanobelts crystallize in wurtzite structure, growing along (1 0 1 ¯ 0) direction. Grain boundaries in Cd foil induce the formation of the mesh pattern structure overwide the surface. And the cluster structure of CdS nanbelts is a result of rapid reaction between H2S and liquid form Cd outpouring through loopholes on the surface.

Polycrystalline samples of La0.5−xYxCa0.5−ySryMnO3 (0 ≤ x ≤ 0.20, 0 ≤ y ≤ 0.22) were synthesized by solid state reaction method. The degree of A-site disorder increases linearly with increasing doping content. Structural analysis of X-ray diffraction shows that samples crystallize in a pure orthorhombic Pnma phase and antisymmetry stretching appears in MnO6 octahedron. Raman spectra illustrate rotationlike mode and antisymmetry stretching mode are both hardened with increasing A-site disordering, indicating the Jahn-Teller distortion strengthened. The metal-insulator transition temperature and MR values are found to decrease with increasing A-site disordering. The suppression of metallic behavior is ascribed to the enhancement of Jahn-Teller effect caused by increasing A-site disordering.

Methane (CH4) has superior economic value and application prospect compared with CO, and is an ideal product for photoreduction of CO2. However, low CO2 conversion efficiency and poor selectivity on production are both obstacles to its practical application. Herein, we develop a “M-scheme” photocatalyst CeO2/Ti3C2/TiO2 (CTT) for superior CO2 reduction and selective CH4 generation. This dual heterojunction is constructed by annealing precursor CeO2/Ti3C2 to form anatase TiO2 in situ. CTT composed by CeO2/Ti3C2 and TiO2/Ti3C2 significantly promotes the charge carrier transfer, improving its photoelectric performance. Ti3C2 exhibits a metallicity in the composite, which not only plays the role of a platform to receive transferred electrons, but also resembles the behavior of precious metals to assist in the decomposition of H2 molecules to H+. The reaction between H+ and CO on Ti3C2 contributes to the decreased by-products and decent CH4 selectivity. This work provides a facile and up-and-coming model to construct “M-scheme” heterojunction, realizing the megamerger between optimized photoelectric performance and selective CO2 photoreduction.

Te doped CdS films are prepared by co-evaporating Tellurium (Te) and Cadmium sulfide (CdS) in a domestic vacuum system. Results of X-ray diffraction (XRD) and Atomic Force Microscope (AFM) show improved crystallinity and surface smoothness at trace Te dopant while the band gap and transmittance maximum remains almost unchanged. Combination of CdS LO and CdTe LO phonon is observed, indicating the well dispersion of Te.

Two water-soluble polysaccharides were obtained from the leaves of Abelmoschus esculentus using aqueous extraction and purification with DEAE-52 and Sephadex G-100. AEP-11 (1.9 × 105 Da) consisted of D-arabinose, D-xylose, D-glucose, D-mannose, and D-galactose in a 2.9:3.1:0.3:0.4:3.4 ratio. AEP-22 (1.6 × 106 Da) consisted of D-arabinose, xylose, D-mannose, and galactose in a 4.7:0.8:0.6:3.9 ratio. AFM and Congo red indicated that the enhanced flexibilities of AEP-11 and AEP-22 chains could lead to agglomerated morphologies and may further confirm random coils instead of triple helical conformations. CD revealed the presence of disordered structure in AEP-22 compared with the ordered structure in AEP-11. In antioxidant activity assay, AEP, AEP-11, and AEP-22 all exhibited strong radical-scavenging capacities (AEP > AEP-11 > AEP-22) and obvious reducing power.

The polycrystalline samples of YMn1−xFexO3 (YMFO) and co-doped Y1−yDyyMn0.8Fe0.2O3 (YDMFO) with x ranging from 0 to 0.7 and y from 0 to 0.2 are synthesized by solid state reaction method and comparatively investigated. Structural analysis by X-Ray diffraction and Raman scattering shows that sample crystallizes in a pure hexagonal P63 cm phase for YMFO with x ≤ 0.2 and all the co-doped compounds. The tilting angle α of MnO5 bipyramids decreases, while the Mn–OT bond lengths are extended with increasing Fe3+ concentration. These parameters are almost not changed in co-doped samples. The structural results indicate that the distortion of MnO5 is weakened by Fe3+ substitution at Mn3+ site, while those are not altered in YDMFO. Magnetic measurements indicate that the antiferromagnetic interaction is suppressed by Fe3+ doping, which is ascribed to the weakened distortion of MnO5 bipyramids. Weak ferromagnetic ordering is found in Dy–Fe co-doped YMnO3 samples at low temperature, which is resulted from the Dy3+−Fe3+/Mn3+ exchange interaction.

A new molecular ferroelectric is discovered in an organic–inorganic hybrid compound, (C6H5NH3)2CdCl4, which undergoes a reversible order–disorder ferroelectric phase transition at 369 K and has a spontaneous polarization of about 0.5 μC cm−2, larger than the Rochelle salt. Large dielectric anomaly, pyroelectricity and P–E hysteresis loop were observed to represent the ferroelectricity of the compound. Especially, the dielectric constant at the transition temperature increases more than 40 times than that at room temperature, which indicates potential applications on switches and sensors for its high-temperature response and excellently reversible characterization.

Laser-induced femtosecond demagnetization, femtomagnetism, offers a potential route to develop faster magnetic storage devices. It is generally believed that the traditional spin-wave theory, which is developed for thermally driven slow demagnetization, can not explain this rapid demagnetization by design. Here we show that this traditional spin-wave theory, once augmented by laser-induced spin-orbit torque, provides a highly efficient paradigm for demagnetization, by capturing low-energy spin-wave excitation that is absent in existing mechanisms. Our paradigm is different from existing ones, but does not exclude them. Microscopically, we find that optical spin-orbit torque generates massive spin waves across several hundred lattice sites, collapsing the long-range spin-spin correlation within 20 fs. Our finding does not only explain new experiments, but also establishes an alternative paradigm for femtomagnetism. It is expected to have far-reaching impacts on future research., 21 pages, 5 figures, 2 tables

We obtained one new molecular ferroelectric material tris(2-hydroxyethyl) ammonium bromide (TAB) that crystallizes in aqueous solution at room temperature with a space group of R3m which belongs to ten polar space groups. There is a paraelectric-to-ferroelectric phase transition at 424 K (from hexagonal R3m to hexagonal R3m phase). Such a high transition temperature is close to that of diisopropylamine bromide (426 K) and higher than that of many other molecular ferroelectrics, such as triethylmethylammonium tetrabromoferrate(III) (360 K); some of the organic-inorganic perovskite ferroelectrics, such as (cyclohexylammonium)2PbBr4 (363 K); and some inorganic ferroelectrics, including BaTiO3 (393 K). The saturated polarization and the coercive field of TAB measured from the ferroelectric hysteresis loop are about 0.54 μC·cm-2 and 0.62 kV/cm, respectively. Given its superior performance, including high phase transition temperature, room-temperature ferroelectricity, small coercive electric field, and adjustable ladder-shaped dielectric constant, TAB will have many potential applications.

The aim of the study was to investigate the endogenous metabolites of patients with psoriasis vulgaris which will be helpful for the diagnosis of the disease and to provide the evidence of pathogenesis and the formulation for the individualized dosage regimen.This study investigated the plasma metabolomic profiling between the psoriasis vulgaris patients (N=12) and the healthy volunteers (N=12) using ultra-performance liquid chromatography/quadrupole time-of-flight mass spectrometry (UPLC/Q-TOF MS) metabolomic techniques. Principal component analysis (PCA) and orthogonal partial least squares discriminant analysis (OPLS-DA) were used to identify and visualize the metabolic data clusters.A total of 22 differential metabolites contributing to the clusters were identified, among which the levels of threonine (p0.001), leucine (p0.001), phenylalanine (p0.001), tryptophan (p=0.018), palmitamide (p0.001), Linoleic amide (p0.001), oleamide (p0.001), stearamide (p0.001), cis-11- eicosenamide (p0.001), trans-13-Docosenamide (p0.001), uric acid (p=0.034), LysoPC (16:0) (p0.001), LysoPC (18:3) (p0.001), LysoPC (18:2) (p=0.024), LysoPC (18:1) (P=0.012) and LysoPC (18:0) (p=0.002) were significantly higher in the plasma of psoriasis vulgaris patients compared with the healthy controls, whereas oleic acid (p0.001), arachidonic acid (p0.001) and N-linoleoyl taurine (p0.001) were significantly lower. These biomarkers are related to glucose metabolism, lipid metabolism, amino acid metabolism, nucleic acid metabolism and so on.The data suggest that psoriasis vulgaris patients may have disrupted lipid and amino acid metabolism, as well as inflammation and functional lesions in the liver and kidney. This study deepens the understanding of psoriasis vulgaris pathogenesis and proposes novel ideas and methods for auxiliary diagnosis and treatment of the disease.

Hybrid organic-inorganic halide perovskites (HOIPs) MAPbBr

Developing a simple and low-cost approach to synthesis of morphologically controllable nanoarrays is still the most desirable task. Herein, we discover a one-step strategy for the Cu2S nanoarray formation in situ on Cu foil, basing on the use of thermal annealing process in an H2S/N2 mixed gas flow. The strategy does not require any of additional catalysts or nano-template. The results indicated that annealing time and annealing temperature are very important for the formation of nanoarrays, which can change the morphologic features obviously. Neat nanoarray growing conditions are the annealing temperature of 200 °C, and the annealing time of 2 h. The hexagonal morphology of the Cu2S nanoarrays gradually decreases in diameter from bottom to top. The crystal structure and formation mechanism of Cu2S are analyzed in detail.

Business digitization has aggravated the existing security and privacy concerns of customers, resulting in new challenges on organizational security and privacy protection. However, our knowledge on whether information security (ISec) studies respond in a timely manner to the requirements of industry and the situational changes in security and privacy brought about by digitizing business is limited. In this study, we fully compared the match between ISec papers published in six leading information system (IS) journals in the last four years and the themes of IBM ISec capability reference model. We evaluated the practical relevance of ISec research in the IS field. Furthermore, we identified four security objects (i.e., data, human behavior, IT/IS, and business processes) in organizations and coded each paper to one or more of these security objects. By examining the interaction between security objects, we provided some suggestions for the research and industry communities.