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Carcinoembryonic antigen-related cell adhesion molecule 6 (CEACAM6) is an immunoglobulin superfamily protein primarily expressed on epithelial surfaces and myeloid cells. It plays a significant role in cancer progression by inhibiting apoptosis, promoting drug resistance, and facilitating cancer cell invasion and metastasis. Overexpression of CEACAM6 has been observed in various cancers, including lung, breast, colorectal, and hepatocellular cancers, and is associated with poorer overall survival and disease-free survival. Its differential expression on tumor cell surfaces makes it a promising cancer marker. This review aims to provide a comprehensive summary of CEACAM6's role in different cancer types, its involvement in signaling pathways, and recent advancements in CEACAM6-targeted treatments. [ABSTRACT FROM AUTHOR]

In the post-pandemic era, there is a need for medical professionals with creativity, clinical expertise, and social responsibility. The Chinese government issued a directive to enhance the "Five Characteristics" perceptions of medical students, incorporating moral integrity and adeptness in saving lives and aiding the injured, embracing a compassionate approach to medical practice, possessing the knowledge essential for academic distinction, mastering technical expertise, and the artistry of applying scientific methodologies. The purpose of this study was to investigate the opinions related to ethics and professional behaviors of medical students at one Chinese medical school using a validated 19-item survey instrument and analyze its influencing factors. We conducted a survey in a medical university in Anhui Province, China, and collected 1966 valid questionnaires using the "Five Characteristics Rating Scale". The results indicated high perceptions of "Five Characteristics" among Chinese medical students (85.42 ± 8.727). Lower-grade-year medical students (86.59 ± 7.888) had higher "Five Characteristics" perceptions than upper-grade-year medical students (84.29 ± 9.327, P < 0.05). In addition, medical students experiencing voluntary work during the COVID-19 pandemic showed higher perceptions (86.21 ± 8.357) than those without such experience (85.13 ± 8.842, P < 0.05). Grade year and voluntary work experience during the COVID-19 pandemic were influencing factors of "Five Characteristics" perceptions. Our research offers a theoretical foundation for governments and medical schools to cultivate doctors with high ethical standards and professional expectations. [ABSTRACT FROM AUTHOR]

We aimed to investigate the safety and efficacy of nirmatrelvir/ritonavir (Paxlovid) therapy for hemodialysis-dependent patients with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. Thirteen hemodialysis patients infected with the Omicron variant of SARS-CoV-2 from April 3 to May 30, 2022, were recruited. Laboratory parameters and chest CT (computed tomography) imaging were analyzed. The treatment group included six patients who received 150 mg/100 mg of Paxlovid orally once daily for 5 days, whereas the control group included seven patients who received basic treatment. No serious adverse reactions or safety events were recorded. Four control patients progressed to moderate disease, and none in the treatment group showed progression of chest CT findings (P < 0.05). Paxlovid therapy tended toward early viral clearance and low viral load on Day 8. Moreover, 83.3% of the patients in the treatment group and 57.1% of the patients in the control group turned negative within 22 days. In the Paxlovid treatment group, we found significantly increased levels of lymphocytes (P=0.03) and eosinophils (P=0.02) and decreased levels of D-dimer on Day 8 compared with those on Day 1. Paxlovid therapy showed a potential therapeutic effect with good tolerance in hemodialysis patients. The optimal dose and effectiveness evaluation must be further investigated in a largeer cohort. [ABSTRACT FROM AUTHOR]

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) was reported at the end of 2019 as a worldwide health concern causing a pandemic of unusual viral pneumonia and many other organ damages, which was defined by the World Health Organization as coronavirus disease 2019 (COVID-19). The pandemic is considered a significant threat to global public health till now. In this review, we have summarized the lessons learnt during the emergence and spread of SARS-CoV-2, including its prototype and variants. The overall clinical features of variants of concern (VOC), heterogeneity in the clinical manifestations, radiology and pathology of COVID-19 patients are also discussed, along with advances in therapeutic agents. [ABSTRACT FROM AUTHOR]

The genesis of giant gold provinces is an international scientific frontier, in which the source of a huge amount of gold and the drive for mineralization are key challenges. The mineralization intensity of the Jiaodong gold province in eastern China is a rare occasion in the world, because it owns gold reserves of ∼5500 tons within an area of less than 10,000 km2. The Jiaodong gold province formed in the superimposed domain of diverse tectonic regimes in an intracontinental setting. Paleoproterozoic regional peak metamorphism and Triassic continental collision are followed by the tectonic transition and gold mineralization at ca. 120 Ma with time intervals of 1.9 billion years and about 100 million years, respectively. The Jiaodong gold deposits are different from orogenic and intrusion-related gold deposits in terms of the tectonic background, types of host rocks, and ore-forming mechanism. These gold deposits show close spatial-temporal and genetic relationships to mafic igneous rocks, implying the derivation of ore-forming fluids from the metasomatic mantle domains. Mafic dykes in Jiaodong have negative εHf(t) values of −29.9 to −9.1, Os content of 0.002–0.16 ppb, heavy δ18O up to 8.23‰, and high initial 187Os/188Os ratios of 0.1352–0.8858. These indicate that the lithospheric mantle was metasomatized by ancient crust-derived components. The lithospheric mantle in the western Jiaodong shows generally more enriched isotope features than that in the eastern part, which is explained to be an important reason for its huge gold resources. The mafic dykes show lighter Mg isotope characteristics (average δ26Mg of −0.33‰, n=50) and high CaO content (overall greater than 6.5 wt%), indicating that the lithospheric mantle would also record the metasomatism by the carbonate rocks from the subducting oceanic slab. Under the background of the rollback of the subducting paleo-Pacific slab and the destruction of the North China Craton, partial melting of the lower crust would produce granitic magmas that led to the enrichment of gold in the residual crust. The syn-mineralization asthenosphere upwelling would promote the recycling of the lower crust and the partial melting of the metasomatic mantle domains. Basic magmas, produced by the partial melting, and the mantle itself would degas to form ore fluids. The ore fluids would further leach gold in the lower crust to increase its fertility. The auriferous fluids were transported to the middle to upper crust along the detachment and strike-slip faults. Water-rock interaction and fluid immiscibility, which occurred in and above the ductile-brittle transition zone to induce gold precipitation, formed the Jiaodong gold deposits. Given the unique geological features and genetic model of the Jiaodong gold deposits, they can be defined as "Jiaodong-type" gold deposits. [ABSTRACT FROM AUTHOR]

High-entropy oxides receive significant attention owing to their "four effects". However, they still suffer from harsh construction conditions such as high temperature and high pressure and present a block-like structure. Herein, in this work, Ni-Mn-Cu-Co-Fe-Al high-entropy layered oxides (HELOs) with a layered nanosheet structure were constructed by a simple pathway of topological transformation under relatively low temperature (300 °C) with six-membered Ni-Mn-Cu-Co-Fe-Al layered double hydroxides (LDHs) precursors, which exhibited an outstanding activity and excellent selectivity for CO2 photoelectroreduction (obtaining the highest carbon monoxide yield of 909.55 µmol·g−1·h−1 under −0.8 V vs. reversible hydrogen electrode (RHE), which is almost twice that of pure electrocatalysis). In addition, the charging voltage of a photo-assisted Zn-CO2 battery with HELOs as electrode was reduced from 2.62 to 2.40 V; the discharging voltage of the battery was increased from 0.51 to 0.59 V with the assistance of illumination. The improvement of round-trip efficiency of the battery indicates that light played a positive role in both the charging and discharging processes. This study not only lays an important foundation for the development of high-entropy oxides but also expands their application in the field of photoelectrochemistry. [ABSTRACT FROM AUTHOR]

Oxygen reduction reaction (ORR) plays a pivotal role in advanced electrochemical energy conversion devices. However, the ORR conversion efficiency is extremely limited. The major obstacles originate from the adsorption and activation of O2 on the electrode surface. A novel nanocomposite catalyst, photosensitizers (PS) meso-tetraphenylporphyrin iron(III) chloride (FePcCl)/NiCoFe-layered double hydroxides (NiCoFe-LDHs) is designed in this study. Herein, owing to excellent oxygen molecules activation ability and remarkable illumination absorption feature, FePcCl/NiCoFe-LDHs is employed to uncover the relationship between the intrinsic ORR activity and PS behaviour. Interestingly, the reaction mechanism of singlet 1O2 is proposed owing to the combination of electrochemical ORR catalysed via LDHs and PS. The boosted cathodic ORR properties exhibit singlet 1O2 dependent response arising from the synergistic effect to selectively produce active intermediates in alkaline medium. This work imparts the promising new mechanism about the high 4-electron ORR selectivity via material design, which will guide the development of photo-assisted energy conversion devices. [ABSTRACT FROM AUTHOR]

WC-Co cemented carbide has been widely used as cutting tool materials under cooling conditions. However, WC-Co cemented carbide has low high temperature hardness and poor oxidation resistance at high temperature, which limits its application in the field of high-speed machining. New WC-Al2O3 composite tool materials with high hardness and excellent oxidation resistance at high temperature were fabricated by vacuum hot pressing sintering process at 1450 °C. The mechanical properties of WC-Al2O3 composite tool materials with different Al2O3 content were studied at room and high temperature, combined with the microstructure analysis by XRD\SEM\EDS. It was found that WA5 (5 wt.% Al2O3) had the best comprehensive mechanical properties at room temperature, but its performance at high temperature was inferior to WA20 (20 wt.% Al2O3). The Vickers hardness of WA20 was 21.3 ± 0.19 GPa at 600 °C, which was higher than WA0 (3.44 ± 0.24 GPa) and WA5 (4.4 ± 0.08 GPa) at 600 °C. The oxidation experiment showed that the weight gain of WA20 at high temperature (700 °C and above) was significantly lower than that of WA0 (0 wt.% Al2O3) and WA5, which was due to the good high temperature oxidation resistance of Al2O3. In general, WA20 had good high temperature mechanical properties and better high temperature oxidation resistance, which was suitable for high-speed cutting tool. [ABSTRACT FROM AUTHOR]

In this paper, a Q-switched and three-color operation of Neodymium-doped silica all-fiber laser is realized, in which, a few-layer transition metal dichalcogenides WS2 is pioneered to be used as a saturable absorber (SA). The compact and simple linear cavity contains homemade fiber mirrors by directly depositing a multilayer coating the SiO2/Ta2O5 dielectric films on fiber end-face. In particular, by inserting the WS2-SA into the FP laser cavity, it is found that a stable Q-switching operation was achieved with the higher signal-to-noise ratios (SNR) of 60.76 dB, and the shortest pulse duration of 990 ns, as well as the maximum repetition rate of 124.4 kHz. Meanwhile, the maximum average output power and maximum pulse energy are close to 8.9 mW and 71.5 nJ, respectively. This is, the first demonstration of compact WS2-based neodymium-doped all-fiber laser operation at 1081.9, 1091.3 and 1100.1 nm. [ABSTRACT FROM AUTHOR]

Mafic lava is generally used to study the oxygen fugacity of lithospheric mantle. However, some studies confirmed that the high oxygen fugacity of mafic lava from lithospheric mantle may be result of auto-oxidation during the late magma evolution. Whether mafic lava reflects the oxygen fugacity of source area remains controversial. The major and trace element compositions of biotite, amphibole, and plagioclase as well as the Sr isotopes of plagioclase were in-situ examined aim to evaluate the variation in oxygen fugacity of mafic magma during transportation from depth to current location. Mineralogical characteristics show that the dikes originate from an enriched lithospheric mantle source and experienced very little or no crustal contamination during the magma transfer process. Clinopyroxene, plagioclase, Al-rich amphibole, biotite, and Mg-rich amphibole crystallized successively as the depth of magma reduced from 75.9 to 0.8 km. Fayalite-magnetite-quartz (△FMQ) and Ni-NiO (△NNO) are used as reference oxygen fugacity buffers in this study. The average oxygen fugacity of mafic magma gradually increases from △NNO-1.50 (lithospheric mantle source) to △NNO + 2.74 (near the surface) during magma evolution. Calculation results from clinopyroxene, amphibole and biotite show that the oxygen fugacity of magma increases during fractionation of clinopyroxene, plagioclase, amphibole, and biotite. However, the above fractionation cannot generate such a wide variation in oxygen fugacity. Moreover, it is not caused by degassing in terms of the low carbonate mineral content and increasing S6+/Stot ratios during fractionation. Previous studies have shown a rapid cooling and a high H2O content of the Jiaodong mafic magma. Combine with the garnet-spinel transition zone of mantle lithosphere and magnetite observed in petrography, we tend to propose that the variation in oxygen fugacity of mafic magma were caused by magnetite-spinel fractional crystallization at depth. Low-pressure metamorphic amphibole and the country rocks of Late Mesozoic monzodiorite, which has a much higher oxygen fugacity than the stable range of magnetite-spinel, indicated that the secondary alteration in last stage of magma evolution may cause additional variation in oxygen fugacity. In that case, mafic lava cannot be used to determine the oxygen fugacity of source rock. [ABSTRACT FROM AUTHOR]

Ammonia is important for industrial development and human life. The traditional Haber Bosch method converts nitrogen into ammonia gas at high temperatures and pressures, causing serious pollution and greenhouse gas emissions. These problems prompt the nitrogen fixation method to proceed in a sustainable way. Ultrathin Ni/V-layered double hydroxides (Ni/V-LDHs) nanosheets with different proportions were prepared successfully for photocatalystic reduction of nitrogen to ammonia, through aqueous miscible organic solvent method (AMO) to achieve the higher surface area and rich oxygen vacancies, containing more carriers and active sites to enhance nitrogen reduction. And the optimal catalyst of Ni/V-LDHs 11 AMO possesses the highest photocatalytic efficiency (176 µmol·g−1·h−1), indicating its potential application prospects in catalyst fields. Consequently, this work achieves an environmentally friendly, low-cost and efficient conversion method for nitrogen reduction to ammonia through solar energy. [ABSTRACT FROM AUTHOR]

As revealed from the results of first-principles calculations, the indium nitride (InN) monolayer is capable of significantly facilitating its interaction with gas molecules after being modified with Transition Metals (TM). Accordingly, the adsorption behavior of Ag-doped InN (Ag–InN) and Pd-doped InN (Pd–InN) monolayers was investigated on two small gas molecules (i.e., SO 2 and NO). To make the proposed material more widely applicable, several critical parameters affecting the performance of gas sensors [e.g., adsorption distance, adsorption energy ( E ad) , charge transfer (QT), and density of state (DOS)] were analyzed in depth. As revealed from the results, both gases were capable of adsorbing stably on the surfaces of Ag–InN and Pd–InN monolayers. In addition, the analysis of electron localization function (ELF), DOS and spin band structure demonstrated the robust chemical interactions between Ag or Pd dopants and the activated atoms in the gas molecules. Given the theoretical results of the present study, we can gain insights into the sensing performance exhibited by the TM Ag as well as Pd modified InN surface. The mentioned prominent properties verified the feasibility of this material as a high-sensitivity gas sensor and could be effectively referenced for its application in sensing and catalytic fields. [ABSTRACT FROM AUTHOR]

Recent years, graphene-based van der Waals (vdW) heterojunction becomes more and more popular in optoelectronics, nanoelectronics, and spintronics device area. Besides, the modulation of Schottky barrier height (SBH) is rather desired to improve the performance of corresponding devices. In the current study, we have focused on the interfacial characteristics and electronic structure of graphene/AlN heterostructure by the first-principles calculations. The results show the intrinsic electronic properties are preserved after graphene and AlN contacting due to the weak interaction between two sublayers. The Bader charge analysis shows that the electrons are transferred from AlN to graphene, leading to graphene as an acceptor while AlN as a donor. Besides, by varying the interlayer distance from 2.5 to 4.3 Å, we found both the n-SBH and p-SBH are significantly tuned. In addition, the optical absorption intensity is enhanced significantly in the graphene/AlN heterojunction. Our findings imply that the SBH is controllable, which is highly desirable in the nano-electronic devices. [ABSTRACT FROM AUTHOR]

In this paper, we have investigated the electronic and magnetic properties of four types of native defects under neutral and charged states in a hexagonal boron phosphide (h-BP) monolayer, including boron vacancy ( V B) , phosphorus vacancy ( V P) , boron on the phosphorus site ( B P) and phosphorus on the boron site ( P B) within the framework of the density functional theory. For the four types of defects, various charge states were investigated, and only 0 and 1 + charge states for all defects are stable within the electronic chemical potential range (i.e. Fermi level range). It is found that B P with the smallest defect formation energy is the most stable defect under both phosphorus-rich and -poor conditions in the whole range of electronic chemical potential. V P and P B are found to be shallow donors (i.e. 1 +/0) but could not be effectively introduced into the h-BP monolayer due to a rather high formation energy, while V B and B P are found to be holes trap centers. Especially, B P with a low defect formation energy, will be produced easily and seriously affect the p-type doping efficiency and conductivity of h-BP. Additionally, V B and V P induce a nonzero magnetic moment while P B and B P show non-magnetic nature in the h-BP monolayer. [ABSTRACT FROM AUTHOR]

The ~ 120 Ma Jiaodong province in the North China Craton, composed of abundant Mesozoic granites that intrude Precambrian metamorphic basement, is bordered by the Sulu orogenic belt, which formed through the collision between the North China and Yangtze cratons in the Triassic. Insights on the geodynamic setting and source of gold and fluids in the Jiaodong gold province are based on a detailed study of the Sanshandao deposit. The δ13CPDB and δ18O values of hydrothermal calcite from this deposit range from − 4.3 to − 6.5‰ and 11.4 to 15.1‰, respectively, which are compatible with a mantle source. Pre-ore mafic dykes in the deposit show typical arc-like geochemical features, suggesting that the mantle source was metasomatized prior to the basic magmatism. The δ34S values of gold-related pyrite from Sanshandao and other large deposits in the province range from 10.9 to 11.5‰ and are higher than those of the country rocks, but consistent with the signature of orogenic gold deposits sourced from a Neoproterozoic sedimentary reservoir. These high positive δ34S values are interpreted to be inherited from auriferous Neoproterozoic sedimentary rocks of the northern Yangtze Craton, which were subducted into the mantle lithosphere beneath the North China Craton during the formation of eclogite in the adjacent Sulu orogenic belt in the Triassic. The syn-ore Lower Cretaceous mafic dykes display oceanic island basalt-like geochemical features, suggesting that asthenosphere upwelling triggered the release of gold and sulfur from an enriched and fertilized mantle lithosphere, contributing to the auriferous fluid which formed the widespread gold mineralization in the Jiaodong province at ca. 120 Ma. [ABSTRACT FROM AUTHOR]

SCNT technology has been successfully used to clone a variety of mammals, but the cloning efficiency is very low. This low efficiency is likely due to the incomplete reprogramming of SCNT embryos. Histone modification and DNA methylation may participate in these events. Thus, it would be interesting to attempt to improve the efficiency of SCNT by using a HDACi VPA. In order to guarantee the effect of VPA and reduce its cytotoxicity, a comprehensive analysis of the cell proliferation and histone modification was performed. The results showed that 0.5 and 1 mM VPA treatment for 24 h were the optimal condition. According to the results, H3K4me3 was increased in 0.5 and 1 mM VPA groups, whereas H3K9me2 was significantly decreased. These are the signals of gene-activation. In addition, VPA treatment led to the overexpression of Oct4 and Nanog. These indicated that VPA-treated cells had similar patterns of histone to zygotic embryos, and may be more favorable for reprograming. A total of 833 cloned embryos were produced from the experimental replicates of VPA-treated donor cells. In 1 mM treatment group, the blastocyst rates were significantly increased compared with control. At the same time, our findings demonstrated the interrelation between DNA methylation and histone modifications. [ABSTRACT FROM AUTHOR]

More than 0.5 billion tons of late Permian bauxite overlies the karstic topography of the Maokou Formation of western Guangxi in China. Here, we provide new mineralogical, geochemical, Sr-Nd-Pb isotopic, and pyrite S isotope and trace element compositional data for the Pingguo bauxite deposit, aiming to further our understanding of the genesis of Permian bauxite. The Pingguo bauxite contains three distinct layers: a lower layer dominated by ferric clay or weathered iron ore, a middle layer of cryptocrystalline and oolitic bauxite ore, and an upper layer dominated by argillaceous bauxite. The bauxite ore is mainly diaspore, pyrite, chamosite, and anatase, whereas the argillaceous bauxite contains diaspore, kaolinite, pyrophyllite, pyrite, and anatase. Two types of pyrite have been identified within the bauxite: fine-grained and framboidal pyrite (Py1) occurring in aggregates and coarse-grained and euhedral pyrite (Py2). Py1 is enriched in trace elements and is thought to have a diagenetic origin, whereas Py2 is deficient in trace elements and is considered to have formed by later recrystallization. The S isotopic composition of pyrite (−34.11 to −18.91‰) and visible ovoid microorganisms within the bauxite provide evidences of microbial activity during bauxite formation. The Sr-Nd-Pb isotopic composition of the bauxite indicates that these ores were generated by the weathering of basalts belonging to the Emeishan Large Igneous Province (LIP) and limestones of the Maokou Formation. Microorganisms were likely to have enhanced the dissolution and weathering of the parent rock and facilitated the precipitation of diaspore under near-surface conditions. [ABSTRACT FROM AUTHOR]

How to express the designer's creative intent in a simple and intuitive way is the main problem in 3d modeling, especially for novice designers. This paper presents a free shape 3d modeling system for creative design based on modified Catmull-Clark subdivision. The system contains a series of easy but novel operations which can be used to change the topology of models, such as creating holes and handles. In order to create sharp features, feature marking operations are provided to specify where the sharp feature is. This system also provides surface conversion function to make the modeling results be compatible with the traditional CAD systems. Firstly, a simple but efficient quad domain division scheme is adopted to generate quad sub-meshes. In order to improve the smoothness at the regular vertices, long boundary curves which across multiple sub-meshes are used to be the boundary constraints while fitting. In this way, the smoothness at regular vertex can be C continuous. We perform experiments for both skilled and novice designers. Results show that our system is easy to operate and can be used to construct complex models with less time. [ABSTRACT FROM AUTHOR]

In recent decades, many additives with different characteristics have been applied to strengthen and toughen AlO-based ceramic cutting tool materials. Among them, SiC whiskers and SiC nanoparticles showed excellent performance in improving the material properties. While no attempts have been made to add SiC whiskers and SiC nanoparticles together into the ceramic matrix and the synergistically toughening effects of them have not been studied. An AlO-SiC-SiC advanced ceramic cutting tool material is fabricated by adding both one-dimensional SiC whiskers and zero-dimensional SiC nanoparticles into the AlO matrix with an effective dispersing and mixing process. The composites with 25 vol% SiC whiskers and 25 vol% SiC nanoparticles alone are also investegated for comparison purposes. Results show that the AlO-SiC-SiC composite with both 20 vol% SiC whiskers and 5 vol% SiC nanoparticles additives have much improved mechanical properties. The flexural strength of AlO-SiC-SiC is 730±95 MPa and fracture toughness is 5.6±0.6 MPa·m. The toughening and strengthening mechanisms of SiC whiskers and nanoparticles are studied when they are added either individually or in combination. It is indicated that when SiC whiskers and nanoparticles are added together, the grains are further refined and homogenized, so that the microstructure and fracture mode ratio is modified. The SiC nanoparticles are found helpful to enhance the toughening effects of the SiC whiskers. The proposed research helps to enrich the types of ceramic cutting tool and is benefit to expand the application range of ceramic cutting tool. [ABSTRACT FROM AUTHOR]

The effect of chitosan-ergothioneine coating (CHER) on the post-mortem quality and shelf life of Japanese sea bass ( Lateolabrax japonicas) stored at 4 ± 1 °C for 16 days was investigated. Four different treatments were used: control without coating, CH with chitosan coating, ER with 0.3 % ergothioneine immersion, and CHER with chitosan containing 0.3 % ergothioneine coating. Sea bass pH value, total volatile basic nitrogen, peroxide value, thiobarbituric acid-reactive substances, biogenic amines, color, texture profile, and microbiological and sensory qualities were measured. The results indicate that treatment with CHER coating inhibited increase of total volatile basic nitrogen, peroxide value, and TBA value; maintained tissue hardness; and reduced microorganism counts, such as Pseudomonas, compared with control treatment. The efficiency was better than that of ER or CH treatment. Furthermore, sea bass treated with chitosan-ergothioneine coating also exhibited a positive effect, causing low biogenic amine content, especially putrescine, cadaverine, and histamine. Sensory evaluation proved the efficacy of chitosan-ergothioneine coating by maintaining the overall quality of sea bass during the storage period. Our study suggests that chitosan-ergothioneine coating might be a promising candidate for maintaining sea bass quality and extending their shelf life. [ABSTRACT FROM AUTHOR]

Novel magnetically recyclable Pd/γ-AlOOH@FeO catalysts were prepared using γ-AlOOH@FeO as a magnetic supporter and nano-Pd particles as the active catalytic component. The structure of the catalysts was characterized by XRD (X-ray diffraction), TEM (transmission electron microscopy), N adsorption-desorption, and a VSM (vibration sample magnetometer). The catalytic activity and recyclability for the Heck coupling reaction were investigated. Results showed that the magnetic γ-AlOOH@FeO possessed a core-shell structure, as well as that the nano-Pd particles were 6-8 nm and had been well dispersed in the γ-AlOOH shell. In the Heck coupling reactions, the magnetic Pd/γ-AlOOH@FeO catalysts exhibited good catalytic activity and recyclability. For the (0.021 mol%)Pd/γ-AlOOH@FeO catalyst, the bromobenzene conversion and product yield reached about 100% and 96.3%, respectively, under a 120°C reaction temperature and 12 h reaction time. After being recycled 8 times, the conversion of bromobenzene and the recovery of the catalyst were about 90% and 93%, respectively. The nano-Pd particles were kept well dispersed in the used Pd/γ-AlOOH@FeO catalyst. [ABSTRACT FROM AUTHOR]

Human acrosin is an attractive target for the discovery of male contraceptive drugs. For the first time, structure-based drug design was applied to discover structurally diverse human acrosin inhibitors. A parallel virtual screening strategy in combination with pharmacophore-based and docking-based techniques was used to screen the SPECS database. From 16 compounds selected by virtual screening, a total of 10 compounds were found to be human acrosin inhibitors. Compound 2 was found to be the most potent hit (IC = 14 μM) and its binding mode was investigated by molecular dynamics simulations. The hit interacted with human acrosin mainly through hydrophobic and hydrogen-bonding interactions, which provided a good starting structure for further optimization studies. [ABSTRACT FROM AUTHOR]

The calculation of charge transition energy level (CTL) and defect formation energy are of significance to explore potential n-type or p-type doping in materials. Based on the first-principles method, this paper systematically studied the structural, magnetic, and defect properties of 12 kinds of dopants in the two-dimensional hexagonal gallium nitride (2D h-GaN) system. The results show that the most stable charge states (MSCSs) for n-type systems are 0 and 1+, and all the n-type substitutes act as shallow donors. The MSCSs of the p-type systems are 1−, 0 and 1+, and the acceptor ionization energy is distributed higher than the valence band maximum (VBM) from ~1.25 to 2.85 eV, acting as deep acceptors, which will capture electrons (holes) in n-(p-type) 2D h-GaN and affect the carrier conductivity. Thus, it is difficult to achieve p-type doping through a single defect in 2D h-GaN, and complex defects are necessary to achieve p-type doping experimentally. [ABSTRACT FROM AUTHOR]

Stress and strain distributions in and around a single or two-coupled pyramidal InAs quantum dots (QDs) embedded in GaAs are calculated by finite element methods according to the continuum elasticity theory. By changing the quantum dot spacing and thickness of cap layer, the results about strain and stress distributions show compressive strain and stress distribution in the QDs and relaxation undergoes two stages with different speeds for different quantum dot height, quantum width and thickness of cap layer. The stress and strain distributions of pyramidal QDs would not vary monotonously with geometric dimensions. The height of quantum dot and cap layer thickness can effectively adjust the vertical correlation of self-assembly QDs according to the calculation. The shape of stress distribution at surface of cap layer can be tuned from a quadrangle into a circle by increasing the thickness of cap layer or decreasing the height of quantum dot. Also, a new approach to grow quantum ring is found in this paper. The calculations of two-coupled QDs show that the self-assembly technology might fail if the horizontal distance between two QDs is not large enough. The stress induced by upper QDs will be relaxed to zero with a longer distance downwards is found in this paper. [ABSTRACT FROM AUTHOR]

In order to strengthen the scientific management of saline-alkali land and the accurate management of agricultural production, a scientific data governance platform for saline-alkali land was developed. Based on the data accumulation of big data platform, the relationship between wheat growth and meteorology was taken as the research object. Thirteen variables including atmospheric pressure, temperature, light, and precipitation were extracted from surface meteorological data for correlation analysis, and temperature, precipitation, and sunshine were selected as the characteristic variables; through discretization processing, we have finally determined the three indicators that can be categorized: accumulative temperature, sunshine hours, and temperature. Finally, the three indicators are combined with months to build a model of farming season and weather based on Apriori. The results show that when judging the farming season with the month as the index, the accuracy of the model is between 78.81 and 100%. When the temperature or accumulated temperature is taken as the index to judge the winter wheat farming time, the accuracy of the model is above 90%. This shows that accurate analysis of farming season can be achieved through big data correlation analysis, which provides technical support for the timely adoption of agricultural production. [ABSTRACT FROM AUTHOR]