Impact of Bullying Victimization on Chinese College Students' Suicidal Tendency: The Moderating Effect of Teachers' Emotional Support and Family Support.

Objective: To explore the influence of bully victims on the suicidal tendencies of college students, and the moderating role of teacher emotional support and family support in the relationship between bully victims and college students' suicidal tendencies, in order to provide a reference for the effective intervention of college students' suicide behavior. Methods: Based on a survey of 15,560 college students. Multiple stepwise regression and Interaction analysis explore the impact of the bully victimization on college students' suicidal tendencies and the moderating role of family support and teacher emotional support in the relationship between the bully victim and college students' suicidal tendencies. Results: This study found that the Suicidal Tendencies score of college students was 19.79 points, indicating that some college students have a risk of suicidal tendencies; secondly, verbal bullying (ß = 0.084, P <0.001), physical bullying (ß = 0.222, P <0.001) and social relationship bullying (ß = 0.122, P <0.001) have a positive and significant impact on the suicidal tendencies of college students; in addition, family support and teacher emotional support have a significant regulatory effect on the bully victim and college students Suicidal Tendencies and family support. The regulating effect was significantly higher than that of teacher emotional support. Conclusion: Chinese college students have the risk of suicidal tendencies; peer bullying victimization is an important reason for affecting college students' suicidal tendencies, teacher emotional support is a protective factor for bully victims to affect college students' suicidal tendencies, and family support has a significant moderating effect on the bully victim and college students' suicidal tendencies. Therefore, it is necessary to actively adopt home-school linkage and home-school communication to reduce campus violence and increase the psychological resilience of college students.

A systematic review and meta-analysis of factors related to non-suicidal self-injury among Chinese adolescents.

BACKGROUND: Over the past several decades the prevalence of adolescent non-suicidal self-injury (NSSI) has been rising steadily. Understanding the factors associated with NSSI is a critical public health concern. The current study aims to explore the critical factors related to NSSI among Chinese adolescents. METHODS: A systematic literature search was conducted to identify the studies meeting our eligibility criteria (published until June 2022) in PubMed, Web of Science, Science Direct, Springer Link, CNKI, VIP, and Wanfang data. The meta-package of R language was used to perform a meta-analysis to compute the pooled effect (r). RESULTS: A total of 59 studies were included in this analysis, with a sample size of 192,546. Twenty-four democratic, personal, and social factors were examined in current study. The pooled effect value (r) has revealed that 23 factors are associated with NSSI behaviors among Chinese adolescents. The factor, Internet addiction, has demonstrated the greatest association with NSSI compared to other factors. CONCLUSION: Consistent with previous studies on adolescent NSSI, findings have demonstrated that a number of demographic, personal, and social factors significantly contribute to NSSI behaviors among Chinese adolescents. Future research on prevention and intervention for adolescent NSSI may benefit from targeting these factors.

16-nor Limonoids from Harrisonia perforata as promising selective 11ß-HSD1 inhibitors.

Two new 16-nor limonoids, harperspinoids A and B (1 and 2), with a unique 7/5/5/6/5 ring system, have been isolated from the plant Harrisonia perforate together with a known one, Harperforin G (3). Their structures were elucidated by NMR spectroscopy, X-ray diffraction analysis and computational modelling. Compound 1 exists as polymorphic crystals. Conformations of 1 in solution were further discussed based on the computational results. These compounds exhibited notable inhibitory activity against the 11ß-HSD1 enzyme. Compound 3 had potencies for the inhibition of human 11ß-HSD1 with high selectivity against 11ß-HSD2 (IC50 0.58 µM, SI > 174). Molecular docking and quantitative structure-activity relationship studies revealed a mixed regulatory mechanism.

Spinal mitochondrial-derived ROS contributes to remifentanil-induced postoperative hyperalgesia via modulating NMDA receptor in rats.

BACKGROUND: Activation of N-methyl-d-aspartate (NMDA) receptor by reactive oxygen species (ROS) in the spinal cord plays an important role in the development of hyperalgesia in several neuropathic pain models. The study examined the involvement of ROS-NMDA signaling pathway in remifentanil-induced postoperative hyperalgesia. METHODS: Nociceptive responses were measured by paw withdrawal mechanical threshold (PWT) and paw withdrawal thermal latency (PWL) before and up to day 5 after remifentanil infusion. Spinal delivery of MitoSOX red was performed to detect mitochondrial ROS. Changes in expression of NMDA receptor subunits (NR1 and NR2B) in the spinal cord were analyzed by immunofluorescence and Western blotting. Intraperitoneal injection of phenyl-N-tert-butylnitrone (PBN), a non-selective ROS scavenger, was administrated to investigate the role of ROS in remifentanil-induced postoperative hyperalgesia. RESULTS: Intraoperative infusion of remifentanil induced postoperative mechanical allodynia and thermal hyperalgesia. ROS production, phosphorylated NR1 and NR2B subunits of NMDA receptor were found to be significantly increased in the spinal dorsal horn after intraoperative remifentanil infusion. However, remifentanil-induced postoperative hyperalgesia was suppressed by pretreatment of PBN. In addition, reduction of ROS by PBN prevented enhanced phosphorylation of NR1 and NR2B subunits. CONCLUSION: These findings indicated that ROS-dependent activation of NMDA receptor in the spinal cord might be a potential mechanism underlying remifentanil-induced postoperative hyperalgesia.

[Research on certified reference material of emodin in rhubarb and its alcohol extract, water extract].

The certified reference materials (CRMs) of emodin in rhubarb and its alcohol extract, water extract were developed by using quantity transfer technology from single chemical composition to the complex systems. The CRM of emodin was used for quantity transfer, and high performance liquid chromatography (HPLC) method was used to determine the contents of emodin in different matrix composition. By establishing mathematical model and calculating the parts of uncertainty, the uncertainty values were finally gotten. CRMs of emodin in rhubarb, alcohol extract and water extract were accomplished. The content values of emodin were 0.40% ±0.03%, 1.15%±0.18%, 0.16%±0.08% (k=2,P=0.95), respectively. The established method for quantity transfer has successfully solved the technical problems that the value of active ingredient of traditional Chinese medicine can't be traced to SI units. The series of CRMs are assigned as grade primary reference materials, which are useful for quality control of the emodin content, also provide the accurate and reliable CRM, materials standard and standard methods.

[Variation of nitrogen during the high suspended sediments concentration water supply in an artificial shallow lake].

The effect of water quality and suspended sediments in the process of water supply is of an increasing concern recently in an artificial shallow lake. The water supply from the Yellow River to Dongchang Lake happened on April 23rd to 25th, 2012. The synchronous monitoring of flow velocity, suspended sediment concentration, dissolved nitrogen and particulate nitrogen concentration was conducted during the three days in five monitoring sites of the longitudinal profile from inlet to outlet. The spatio-temporal variation of nitrogen and the relationship between nitrogen concentration and suspended sediment concentration was analyzed. Moreover, the analysis of different nitrogen forms in surface water and bottom sediment was also made in the whole lake before and after the water supply. Results showed that the process of water supplement had an obvious effect on flow velocities and suspended sediment concentrations around the inlet area. The influence area was a limited scope. The spatial distribution of nitrogen presented a certain concentration gradient along the flow direction. Around the water inlet, concentrations of all nitrogen forms in water and bottom sediment was higher than those in other lake zones. The amplitude of variation of all nitrogen concentrations in surface water, suspended sediments showed a decreasing trend from water inlet to outlet. And concentrations of total dissolved and particulate nitrogen increased at different ratios after water supply in the lake. Total particulate nitrogen concentration increase was higher. It revealed the water supply of the Yellow River had a great influence on lake water. The dissolved nitrogen was the main nitrogen form in water supply. The ratio of total dissolved nitrogen to particulate nitrogen was 7.3 : 1. Nitrate was the primary form in dissolved nitrogen, and ammonium was the primary form in particulate nitrogen, respectively. The correlation between concentration of suspended sediments and ammonium, total nitrogen were notable during te water supply, the correlation coefficient were 0.868 and 0.876. Ammonium was mainly influenced by water supply and adsorption and precipitation of suspended sediments. However, the concentration of nitrate was not influenced. Organic nitrogen was the main form in bottom sediment. It meant that the Yellow River water and suspended sediments were the input sources of nitrogen to Dongehang Lake.

[Degradation of the absorbed methyl mercaptan by persulfate in alkaline solution].

Methyl mercaptan (CH3SH) is considered to be an important contributor to odors. It is a toxic, corrosive and acid gas. The absorption of CH3SH by alkaline solution is one of the most widely used processes, but the remained solution should be further treated. The degradation of dissolved CH3S- by persulfate (PS) oxidation has not been reported. CH3SH is absorbed in alkaline solution and degraded by PS oxidation using a recycling continuous system for absorption and degradation. The stability of PS under alkaline conditions is discussed. The influence of different reaction conditions on the absorption rate and degradation rate is also studied. It was observed that PS was relatively stability under alkaline conditions and the dissolved CH3S- could be degraded effectively by PS. The absorption rate of CH3SH first increased and then decreased with the increasing concentration of PS. The degradation rate of CH3S- increased with the increasing concentration of PS. It was also observed that the efficiency between absorption and degradation had been significantly increased with the increasing of pH. In the conditions of pH = 12, fixed CH3SH concentration of 80 mg x m(-3) with a fixed gas flow rate of 1.5 L x min(-1), 1.4 g x L(-1) PS, 90% of the dissolved CH3S- can be degraded.

[Activated carbon catalyzed persulfate oxidation of azo dye acid orange 7 in aqueous solution].

Persulfate oxidation is a recently emerging advanced oxidation process for the pollution control. Persulfate (PS) degradation of azo dye acid orange 7 (AO7) in an aqueous solution was studied in the presence of suspended granular activated carbon (GAC) at ambient temperature (e. g., 25 degrees C). It was observed that in the GAC/PS combined system AO7 was not only a good decolorization as well as a good mineralization. The AO7 decolorization ratio, the removal efficiency of the naphthalene ring and the removal of TOC were 80%, 50% and 48%, respectively, at PS/AO7 molar ratio of 100: 1, GAC dosage of 1.0 g/L in 5 h reaction time. As a catalyst, GAC can be reused for several times. For each reuse cycle, AO7 removal efficiencies gradually decreased, however, with the oxidant concentration increased, the extent of the deactivation of GAC decreased. The removal efficiencies of AO7 for each reuse cycle hardly changed, and were all above 90% at PS/AO7 molar ratio of 500: 1, GAC dosage of 1.0 g/L in 5 h reaction time. The adsorption capacity of reused GAC decreased as the reuse time increased. The results of surface oxygen function groups, scanning electron microscopy (SEM) and energy disperse spectroscopy (EDS) analysis of reused GAC changed slightly. Therefore, the reason leading to deactivation of GAC could be that adsorption took up the active sites, thus reducing PS's opportunities to contact with the surface of GAC.

The first genetic map of pigeon pea based on diversity arrays technology (DArT) markers.

With an objective to develop a genetic map in pigeon pea (Cajanus spp.), a total of 554 diversity arrays technology (DArT) markers showed polymorphism in a pigeon pea F(2) mapping population of 72 progenies derived from an interspecific cross of ICP 28 (Cajanus cajan) and ICPW 94 (Cajanus scarabaeoides). Approximately 13% of markers did not conform to expected segregation ratio. The total number of DArT marker loci segregating in Mendelian manner was 405 with 73.1% (P > 0.001) of DArT markers having unique segregation patterns. Two groups of genetic maps were generated using DArT markers. While the maternal genetic linkage map had 122 unique DArT maternal marker loci, the paternal genetic linkage map has a total of 172 unique DArT paternal marker loci. The length of these two maps covered 270.0 cM and 451.6 cM, respectively. These are the first genetic linkage maps developed for pigeon pea, and this is the first report of genetic mapping in any grain legume using diversity arrays technology.

Chemical constituents from fruits of Harrisonia perforata.

Eight limonoids (1-8) including three A, B and D-seco-16-nor-type ones, 5,6-dehydrodesepoxyharperforin C2 (1), harrpernoid B (2), and its C-9S epimer, harrpernoid C (3), along with six known compounds (9-14), were isolated from fruits of Harrisonia perforata. Extensive spectroscopic analysis was used to elucidate their structures and stereochemistries. Further confirmation of structures of 1 and 2 were obtained by single-crystal X-ray diffraction. Limonoids (1-8) were evaluated for their anti-tobacco mosaic virus activity and in vitro cytotoxicity against A549 and HL60 cell lines; only compound 2 showed weak activity.

[Chloride interference in the determination of COD of landfill leachate].

Chemical oxidation demand (COD) is one of the most important determination indicators of landfill leachate. However, the presence of high concentration chloride in leachate generates interference, which hasn't caused enough concern. The objective of this paper is to compare anti-interference ability of chloride among potassium dichromate reflux method, rapid digestion-spectrophotometric method, basic potassium permanganate method and UV spectrophotometry method. For the traditional potassium dichromate reflux method, masking agent can't prevent the chloride interference completely when the concentration of chloride is more than 3550 mg x L(-1). The same thing happens with rapid digestion-spectrophotometric method. Though basic potassium permanganate method can successfully obviate the interference from chloride, low oxidizing ability results in more errors in COD measurement, and the efficiency of potassium permanganate is only 60% of potassium dichromate. UV spectrophotometry can not only shorten the measure time and improve the efficiency, but also avoid the interference from chloride. The result indicates that when COD values is less than 150 mg x L(-1), there is a prominent correlation between UV254 and COD, with a correlation coefficient of 0.9985. Furthermore, when COD values is less than 600 mg x L(-1), the correlation between UV365 and COD is more prominent than UV254, with a correlation coefficient of 0.9996.

Chemical constituents from the leaves and stems of Schisandra rubriflora.

Six new nortriterpenoids, schirubridilactones A-F (1-6), as well as 14 known compounds, were isolated from the leaves and stems of Schisandra rubriflora. The structures of 1-6 were elucidated on the basis of spectroscopic methods including HSQC, HMBC, (1)H-(1)H COSY, and ROESY NMR experiments. The relative stereochemistry of 1 was confirmed through single-crystal X-ray analysis. In addition, compounds 1-6 showed anti-HIV-1 activity with EC(50) values in the range 14.3-80.8 microg/mL and selectivity indices in the range 2.2-9.0.

Lactones from Angiopteris caudatiformis.

Angiopterlactones A (1) and B (2), two unique lactones, and three known lactones, osmundalactone (3), osmundalin (4), and 3,5-dihydroxy-gamma-caprolactone (5), have been isolated from the rhizome of Angiopteris caudatiformis. The structures of 1 and 2 were determined by NMR and MS methods, and the structure of 2 was confirmed by X-ray crystallography. The absolute configurations of 1 and 2 were assigned by application of the CD excitation chirality method and the modified Mosher's method. Compound 1 was slightly cytotoxic against HeLa cells, with an IC(50) value of 68.8 microM, and compounds 3 and 4 showed moderate insect antifeeding activity against Plutella xylostella and Heliothis virescens.

Selaginellin A and B, two novel natural pigments isolated from Selaginella tamariscina.

Two new unusual natural pigments were first isolated from the whole herbs of Selaginella tamariscina. The structure of selaginellin A (1) was established as (R,S)-4-[(4'-hydroxy-3-((4-hydroxyphenyl)ethynyl)biphenyl-2-yl)(4-hydroxyphenyl)methylene]-2,5-cyclohexadien-1-one and selaginellin B (2) as (R,S)-4-[(4'-methoxy-4-(methyl)-3-((4-methoxyphenyl)ethynyl)biphenyl-2-yl)(4-methoxyphenyl)methylene]-2,5-cyclohexadien-1-one, along with four known biflavonoids, amentoflavone (3), hinokiflavone (4), heveaflavone (5), and 7''-O-methylamentoflavone (6). Their chemical structures were elucidated by spectral analysis of electrospray ionization mass spectroscopy (ESI-MS), one-dimensional nuclear magnetic resonance spectroscopy (1D-NMR) and two-dimensional-nuclear magnetic resonance spectroscopy (2D-NMR) including (1)H-NMR, (13)C-NMR, distortionless enhancement by polarization transfer (DEPT) and heteronuclear multiple bond coherence (HMBC), and single-crystal X-ray diffraction techniques.

Role of the reduction site in the fluorinated or sulfated TiO2 photocatalytic process.

In this article, the effects of TiO2 surface fluorination and sulfation, on the active oxygen species formed at the reduction site in the photocatalytic process, namely O2*- and H2O2, were investigated from a new perspective. The superoxide radical, (O2*-), was determined by colorimetry of nitroblue tetrazolium, a prominent O2*- scavenger. Hydrogen peroxide (H2O2) was estimated by using the iodide-starch method. In the naked TiO2 photocatalysis, O2*-, though less reactive, was a very important intermediate. When the TiO2 surface was fluorinated, more O2*- and H2O2 were produced, which indicated that the surface modification could greatly reduce the recombination of photogenerated electrons and holes, thus enhancing the photocatalytic rate. In the sulfated system, photocatalysis proceeded with a more complicated mechanism. These results added support to the view of fluoride-induced enhancement and sulfide's nonappreciable inhibition effect.

Enhanced photocatalytic activity of TiO2 by surface fluorination in degradation of organic cationic compound.

Experiments were carried out to investigate the influence of TiO2 surface fluorination on the photodegradation of a representative organic cationic compound, Methylene Blue (MB). The electropositive MB shows poor adsorption on TiO2 surface; its degradation performs a HO-radical-mediated mechanism. In the F-modified system, the kinetic reaction rate enlarged more than 2.5 fold that was attributed mainly to the accumulating adsorption of MB and the increased photogenerated hole available on the F-modified TiO2 surface.

Reaction site and mechanism in the UV or visible light induced TiO2 photodegradation of Orange G.

For TiO2 heterogeneous reaction, the reaction site and the detailed mechanism are interesting and controversy topics. In this paper, effects of surface fluorination of TiO2 on the photocatalytic degradation of an azo dye, Orange G(OG) under UV or visible light irradiation were investigated, and the possible reaction site and mechanism were elucidated. The adsorption of OG on TiO2 was nearly inhibited by fluoride but its UV light induced photodegradation rate was greatly increased by a factor of about 2.7, which was due to the more generated free hydroxyl radicals. It supported the views that fluoride could desorb the oxidant species from surface and that the reaction sites could move to the bulk solution. In TiO2/Vis system, the observed inhibition effects of fluorination could be interpreted by the competitive adsorption, which provided additional evidences that the visible light sensitized photodegradation of dye pollutants on the catalyst surface.

Involvement of chloride anion in photocatalytic process.

The effect of Cl- on photocatalytic degradation (PCD) of pollutants is an important factor since it is ubiquitous in nature. In general, Cl- showed an inhibition on photodegradation due to its scavenging HO* radicals. In this paper, experiments were carried out to examine the effects of Cl- on the PCD of Methylene Blue (MB) and Orange II (OII) in aqueous TiO2 suspensions under UV light illumination. It was found that low concentration of Cl- (< 0.01 mol/L) showed little influence on both dyes, however, high concentration of Cl (> 0.10 mol/L) had a very different influence on the decolorization of dyes: a significant inhibition for MB but a great promotion for OII. In the presence of 0.50 mol/L Cl-, the rate decreased by 70% for MB while increased 7.5-fold for OII. Furthermore, two bands in the ultraviolet region of OII were rapidly broken down. The proposed mechanism was discussed in detail.