With the rapid development of higher education in China, the scale of colleges and universities is expanding, and the phenomenon of campus socialization is becoming more and more obvious. In ...particular, the campus and its surrounding environment are becoming more and more complex, which brings many hidden dangers in university life.
In order to improve the effectiveness of safety education in colleges and universities and maintain the long-term effectiveness of college students' safety awareness, the paper proposes the construction and practice path of college safety education mechanism that integrates the psychological characteristics of students in the new era.
Security issues facing universities at home, this track identifies the relationship between campus security incidents and security education and advocacy. Eight solutions to prevent and reduce incidents in schools. The paper proposes to give importance to the study of the security of college students, to create an awareness of security questions in the bank based on the recommendation algorithm, and to create to have online learning and testing for safety awareness.
The passing rate of 10 majors such as humanities, composition and theory of composition technology was 100%, accounting for 12% of the 83 enrolled majors, and the passing rate of 54 majors such as clinical medicine was over 90%.
The safety online learning and testing system of college students' safety education is lively in form and highly accepted by students. The development of college students' safety education starts from the time of receiving the university admission notice, making full use of the "golden time," so as to effectively prevent and reduce the occurrence of campus safety accidents.
The past decade has witnessed an explosion in the use of super-resolution fluorescence microscopy methods in biology and other fields. Single-molecule localization microscopy (SMLM) is one of the ...most widespread of these methods and owes its success in large part to the ability to control the on–off state of fluorophores through various chemical, photochemical, or binding–unbinding mechanisms. We provide here a comprehensive overview of switchable fluorophores in SMLM including a detailed review of all major classes of SMLM fluorophores, and we also address strategies for labeling specimens, considerations for multichannel and live-cell imaging, potential pitfalls, and areas for future development.
PharmMapper is a web server for drug target identification by reversed pharmacophore matching the query compound against an annotated pharmacophore model database, which provides a computational ...polypharmacology prediction approach for drug repurposing and side effect risk evaluation. But due to the inherent nondiscriminative feature of the simple fit scores used for prediction results ranking, the signal/noise ratio of the prediction results is high, posing a challenge for predictive reliability. In this paper, we improved the predictive accuracy of PharmMapper by generating a ligand–target pairwise fit score matrix from profiling all the annotated pharmacophore models against corresponding ligands in the original complex structures that were used to extract these pharmacophore models. The matrix reflects the noise baseline of fit score distribution of the background database, thus enabling estimation of the probability of finding a given target randomly with the calculated ligand–pharmacophore fit score. Two retrospective tests were performed which confirmed that the probability-based ranking score outperformed the simple fit score in terms of identification of both known drug targets and adverse drug reaction related off-targets.
Abstract
Biological processes (like microbial growth & physiological response) are usually dynamic and require the monitoring of metabolic variation at different time-points. Moreover, there is clear ...shift from case-control (N=2) study to multi-class (N>2) problem in current metabolomics, which is crucial for revealing the mechanisms underlying certain physiological process, disease metastasis, etc. These time-course and multi-class metabolomics have attracted great attention, and data normalization is essential for removing unwanted biological/experimental variations in these studies. However, no tool (including NOREVA 1.0 focusing only on case-control studies) is available for effectively assessing the performance of normalization method on time-course/multi-class metabolomic data. Thus, NOREVA was updated to version 2.0 by (i) realizing normalization and evaluation of both time-course and multi-class metabolomic data, (ii) integrating 144 normalization methods of a recently proposed combination strategy and (iii) identifying the well-performing methods by comprehensively assessing the largest set of normalizations (168 in total, significantly larger than those 24 in NOREVA 1.0). The significance of this update was extensively validated by case studies on benchmark datasets. All in all, NOREVA 2.0 is distinguished for its capability in identifying well-performing normalization method(s) for time-course and multi-class metabolomics, which makes it an indispensable complement to other available tools. NOREVA can be accessed at https://idrblab.org/noreva/.
Rare earth (RE=La, Er, Nd) doped ZnO nanopowders were prepared by the chemical method. The structure and morphology of the synthesized samples were systematically investigated by X-ray diffraction ...(XRD) and scanning electron microscope (SEM), respectively. The results showed that REs were incorporated into ZnO lattices and formed nanopowders. Absorption spectra of doped ZnO exhibited enhanced optical absorption in visible region, and photoluminescence (PL) study revealed that pure and REs doped ZnO had different IUV/IDLE ratios, which was also correspond to the structural analyses. In addition, the electronic structures of pure and REs doped ZnO were studied by the first-principles method. It was indicated that the Fermi levels shifted upward into the conduction bands and obtained n-type conductivities after REs doping. The calculated optoelectronic properties of REs doped ZnO were mainly affected by the 4f electrons of Er/Nd and 6s electrons of La, which were closed to the Fermi-levels and had a significant impact on the related properties. Besides, the imaginary parts of dielectric function of REs doped ZnO presented a red shift in low energy part, and the absorption spectra of which larger than that of pure ZnO. It was also found that the defects formation energies of REs doped ZnO on O-rich conditions were lower than that of on Zn-rich conditions, implying a more stable incorporation of REs on O-rich conditions.
Wocan Hydrothermal Field located on an axial volcanic ridge on the Carlsberg Ridge. The main Ag-carriers were late-stage Cu sulfides in Cu-rich chimney. Display omitted
•First present seafloor ...hydrothermal mineralization processes on the slow-spreading Carlsberg Ridge.•The Cu-rich chimneys were formed at slightly lower temperatures than Cu-rich and Fe-rich massive sulfides.•The main Ag-carriers were both late-stage Cu sulfides and Fe sulfides.•Fluid mixing of hydrothermal fluids with seawater might result in significant redistributions of trace elements.
The basalt-hosted Wocan Hydrothermal Field (WHF), located on the NW slope of an axial volcanic ridge at a depth of ∼3000m at 6°22′N on the slow-spreading Carlsberg Ridge, northwest Indian Ocean, was discovered in 2013 during Chinese DY28th cruise. Preliminary investigations show that the field consists of two hydrothermal sites: Wocan-1, which shows indications for recent high-temperature hydrothermal activity, is located near the peak of the axial volcanic ridge at a water depth of 2970–2990m, and Wocan-2 site, located at a water depth of 3100m, ∼1.7km to the northwest of Wocan-1. The recovered hydrothermal precipitates can be classified into four groups: (i) Cu-rich chimneys; (ii) Cu-rich massive sulfides; (iii) Fe-rich massive sulfides; and (iv) silicified massive sulfides. We conducted mineral texture and assemblage observation and Laser-ablation ICP-MS analyses of the hydrothermal precipitates to study the mineralization processes. Our results show that there are distinct systematic trace element distributions throughout the different minerals in the four sample groups. In general, chalcopyrite from the group (i) is enriched in Pb, As, Mo, Ga, Ge, V, and Sb, metals that are commonly referred to as medium- to low-temperature elements. In contrast these elements are present in low contents in the chalcopyrite grains from other sample groups. Selenium, a typical high-temperature metal, is enriched in chalcopyrite from groups (ii) and (iv), whereas Ag and Sn are enriched only in some silicified massive sulfides. As with chalcopyrite, pyrite also shows distinct trace element associations in grains with different habitus. The low-temperature association of elements (Pb, Mo, Mn, U, Mg, Ag, and Tl) is typically present in colloform/framboidal pyrite, whereas the high-temperature association (Se, Co, and Bi) is enriched in euhedral pyrite. Sphalerite in the groups (i) and (iii) at Wocan-1 is characterized by high concentrations of Ga, Ge, Pb, Cd, As, and Sb, indicating that sphalerite in these sample groups likely precipitated at intermediate temperatures. Early bornite, which mainly occurs in the central part of the Cu-rich chimney, is typically enriched in Sn and In compared to the other minerals. In contrast, late bornite that likely formed during increasing interaction of hydrothermal fluids with cold, oxygenated seawater has low Sn and In, but significantly higher concentrations of Ag, Au, Mo and U. Digenite, also forming in the exterior parts of the samples during the late stages of hydrothermal fluid venting, is poor in most trace elements, except Ag and U. The notable Ag enrichment in the late-stage mineral assemblages at both Wocan-1 and Wocan-2 may therefore be related to lower temperatures and elevated pH. Our results indicate that Wocan-1 has experienced a cycle of heating with Cu-rich chimney growth and subsequent cooling, followed by late seafloor weathering, while Wocan-2 has seen intermediate- to high-temperature mineralization followed by intense silicification of sulfides. Seafloor weathering processes or mixing of hydrothermal fluids with seawater during the waning stages of hydrothermal fluid flow result in significant redistributions of trace elements in sulfide minerals.
Molybdenum disulfide (MoS2) has attracted extensive attention as a non-noble metal electrocatalyst for hydrogen evolution reaction (HER). Controlling the skeleton structure at the nanoscale is ...paramount to increase the number of active sites at the surface. However, hydrothermal synthesis favors the presence of the basal plane, limiting the efficiency of catalytic reaction. In this work, perfect hollow MoS2 microspheres capped by hollow MoS2 nanospheres (hH-MoS2) were obtained for the first time, which creates an opportunity for improving the HER electrocatalytic performance. Benefiting from the controllable hollow skeleton structure and large exposed edge sites, high-efficiency HER activity was obtained for stacked MoS2 thin shells with a mild degree of disorder, proving the presence of rich active sites and the validity of the combined structure. In general, the obtained hollow micro/nano MoS2 nanomaterial exhibits optimized electrocatalytic activity for HER with onset overpotential as low as 112 mV, low Tafel slope of 74 mV decade–1, high current density of 10 mA cm–2 at η = 214 mV, and high TOF of 0.11 H2 s–1 per active site at η = 200 mV.
We developed a novel approach called SHAFTS (SHApe-FeaTure Similarity) for 3D molecular similarity calculation and ligand-based virtual screening. SHAFTS adopts a hybrid similarity metric combined ...with molecular shape and colored (labeled) chemistry groups annotated by pharmacophore features for 3D similarity calculation and ranking, which is designed to integrate the strength of pharmacophore matching and volumetric overlay approaches. A feature triplet hashing method is used for fast molecular alignment poses enumeration, and the optimal superposition between the target and the query molecules can be prioritized by calculating corresponding “hybrid similarities”. SHAFTS is suitable for large-scale virtual screening with single or multiple bioactive compounds as the query “templates” regardless of whether corresponding experimentally determined conformations are available. Two public test sets (DUD and Jain’s sets) including active and decoy molecules from a panel of useful drug targets were adopted to evaluate the virtual screening performance. SHAFTS outperformed several other widely used virtual screening methods in terms of enrichment of known active compounds as well as novel chemotypes, thereby indicating its robustness in hit compounds identification and potential of scaffold hopping in virtual screening.
Hydrothermal activity on mid‐ocean ridges plays an important role in shaping marine chemistry, yet the variability of hydrothermal venting and its forcing mechanism remain elusive. Here, we analyzed ...a sediment core obtained near the tectonic‐controlled Tianxiu vent field, Carlsberg Ridge, to reconstruct the hydrothermal venting history. The core documented two significant hydrothermal events (H1 and H2) in the past 30 ka. H1 occurred at 24.1–24.5 ka during the Last Glacial Maximum (LGM), while H2 occurred at 10.5–11.6 ka during the deglacial period. Compared to H2, H1 was relatively weak, and it occurred concurrently with a tectonic event. We suggest that H2 was caused by the increased melt production associated with the decompression melting of the upper mantle during sea‐level fall, which is consistent with previously published records, whereas H1 was likely triggered by an intense tectonic event associated with depressurization during the LGM, which was previously unrecognized.
Plain Language Summary
Hydrothermal systems are controlled not only by magmatism but also by tectonism. Previous studies have shown that there is a relationship between the variability of hydrothermal activity and sea‐level changes. Increased melt production during glacial periods has been invoked to explain the enhanced hydrothermal activities during glacial terminations. However, little attention has been paid to the relationship between hydrothermal activity and tectonic events during the glacial–interglacial cycle. Based on the analysis of a sediment core collected near the tectonic‐controlled Tianxiu vent field, Carlsberg Ridge, we reconstructed the hydrothermal venting history and found that enhanced hydrothermal activities not only occurred at 10.5–11.6 ka during the last glacial termination but also occurred concurrently with an intense tectonic event at 24.1–24.5 ka during the Last Glacial Maximum. We infer that this earlier hydrothermal event was induced by the improved permeability of the oceanic crust due to depressurization during the glacial sea‐level fall. This is the first time that the hydrothermal venting history of a tectonic‐controlled hydrothermal system in the Indian Ocean is characterized, and the coupling between hydrothermal and tectonic events associated with sea‐level changes is revealed.
Key Points
A 30 ka history of hydrothermal and tectonic activity was reconstructed for the Tianxiu vent field
The hydrothermal event at 24.1–24.5 ka was triggered by tectonic events resulting from depressurization during the Last Glacial Maximum
The hydrothermal event at 10.5–11.6 ka was caused by increased decompression melting of the upper mantle during the Last Glacial Maximum
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► Pyrite FeS2 crystallites were prepared by using K4Fe(CN)6·3H2O as Fe source. ► The as-prepared pyrite FeS2 could high-efficiently degrade organic dyes. ► The adsorption ability of ...the FeS2 crystallites is much higher than their photocatalytic degradation capacity.
FeS2 crystallites were synthesized successfully via a solvothermal method, using potassium ferrocyanide K4Fe(CN)6·3H2O as Fe source, sulfur powder as S source in the presence of polyvinyl pyrrolidone (PVP) as dispersant. And potassium carbonate provided an alkaline environment. The phase and morphology of the products were characterized by means of X-ray powder diffraction (XRD) and scanning electron microscopy (SEM). It was found that the temperature and solvent ratio (VEtOH:VH2O) play a crucial role in the formation of FeS2 with a cubic phase structure (pyrite). Then based on a series of experiments, the possible formation mechanism of pyrite FeS2 crystallites was proposed. In addition, research also showed that the as-prepared pyrite FeS2 crystallites could high-efficiently absorb or photocatalytically degrade some organic dyes such as Methylene blue (MB), Safranine T, Methyl orange (MO), Rhodamine B (Rh B) and Pyronine B. Furthermore, the adsorption and photocatalytic degradation abilities of FeS2 for organic dyes were also compared.
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