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Although collective trolling poses a growing threat to both individuals and virtual community owners, the information systems (IS) literature lacks a rich theorization of this phenomenon. To address the research gaps, we introduce the concept of we-intention to capture the collective nature of collective trolling in virtual communities. We also integrate the social identity model of deindividuation effects (SIDE) and situational action theory to invoke the sociotechnical perspective in theorizing collective trolling in virtual communities. The objective of this study is to use the sociotechnical perspective to understand the we-intention to participate in collective trolling in virtual communities. We test our proposed model using data gathered from 377 Reddit users. Our moderated mediation analysis elaborates how technical elements (i.e., anonymity of self and anonymity of others) influence the we-intention to participate in collective trolling via individual-based social elements (i.e., perceived online disinhibition and social identity), with an environment-based social element (i.e., the absence of capable guardianship) as a boundary condition. We contribute to research by explaining collective trolling in virtual communities from the group-referent intentional action perspective and sociotechnical perspective. We also offer practical insights into ways to combat collective trolling in virtual communities.

A novel tandem photocycloaddition/dehydrogenative aromatization with hydrogen evolution of ortho biaryl-appended 1,3-dicarbonyl compounds for the synthesis of 10-phenanthrenol via cobaloxime catalysis is disclosed.

Objective To clarify the hotspots and trends of multimorbidity research and to provide evidence for further research in China. Methods Papers on multimorbidity were retrieved from PubMed and Web of Science (from inception to August 11,2021).BICOMB and gCLUTO were used for bibliometric and clustering analysis,and CiteSpace was employed for analysis of authors and citations,and burst detection of keywords. Results The research on multimorbidity has been on the rise.Among the authors,Mercer SW published the most papers on this topic and Fortin M was the most cited author.Karolinska Institute topped the institutions in the number of published papers,and the paper published in

The decompositions of separable Werner state, and also isotropic state, are well-known tough issues in quantum information theory, in this work we investigate them in the Bloch vector representation, exploring the symmetric informationally complete positive operator-valued measure (SIC-POVM) in the Hilbert space. We successfully get the decomposition for arbitrary $N\times N$ Werner state in terms of regular simplexes. Meanwhile, the decomposition of isotropic state is found to be related to the decomposition of Werner state via partial transposition. It is interesting to note that in the large $N$ limit, while the Werner states are either separable or non-steerably entangled, most of the isotropic states tend to be steerable., Comment: Few typos are corrected

Objective To establish a mouse model of exogenous iron overload combined with tuberculosis(TB). Methods C57BL/6N mice were divided into negative control, low-, medium-, and high-dose iron groups and received intraperitoneal injection of iron dextran at 0, 3.75, 7.50, and 15.00 mg/dose(3 times/week for 4 weeks), respectively.After 4 weeks, the organ morphology and body weight of the mice were evaluated.The content of serum iron, ferritin, transferrin, and transferrin receptor was determined by ELISA.Heart, liver, spleen, lung, kidney, and small intestine were analyzed for tissue iron content and iron deposition pathology.

Background More than 210,000 medical workers have fought against the outbreak of Coronavirus Disease 2019 (COVID-19) in Hubei in China since December 2019. However, the prevalence of mental health problems in frontline medical staff after fighting COVID-19 is still unknown. Methods Medical workers in Wuhan and other cities in Hubei Province were invited to participate a cross-sectional and convenience sampling online survey, which assessed the prevalence of anxiety, insomnia, depression, and post-traumatic stress disorder (PTSD). Results A total of 1,091 responses (33% male and 67% female) were valid for statistical analysis. The prevalence was anxiety 53%, insomnia 79%, depression 56%, and PTSD 11%. Healthcare workers in Wuhan were more likely to face risks of anxiety (56% vs. 52%, P = 0.03) and PTSD (15% vs. 9%, P = 0.03) than those in other cities of Hubei. In terms of educational attainment, those with doctoral and masters’ (D/M) degrees may experience more anxiety (median of 7.0, [interquartile range (IQR) 2.0–8.5] vs. median 5.0 [IQR 5.0–8.0], P = 0.02) and PTSD (median 26.0 [IQR 19.5–33.0] vs. median 23.0 [IQR 19.0–31.0], P = 0.04) than those with lower educational degrees. Conclusions The mental problems were an important issue for the healthcare workers after COVID-19. Thus, an early intervention on such mental problems is necessary for healthcare workers.

Intervertebral disc degeneration (IVDD) is one of the major causes of low back pain, but effective therapies are still lacking because of its complicated pathology. It has been demonstrated that increased levels of interleukin-1β (IL-1β) may promote the development of IVDD. Cardamonin (CAR) is a chalcone extracted from Alpinia katsumadai and other plants. It exhibits an anti-inflammatory effect in multiple diseases. In the present study, we investigated the protective effects of CAR on rat nucleus pulposus (NP) cells under IL-1β stimulation in vitro and in a puncture-induced rat IVDD model in vivo. We explored the CAR treatment's inhibition of the expression of inflammatory factors such as cyclooxygenase-2 (COX-2), inducible nitric oxide synthase (iNOS), prostaglandin E2 (PGE2), nitric oxide (NO), tumor necrosis factor alpha (TNF-α) and interleukin-6 (IL-6) in rat NP cells. Moreover, the up-regulation of matrix metalloproteinase-13 (MMP-13) and thrombospondin motifs 5 (ADAMTS-5) and the degradation of aggrecan and collagen II induced by IL-1β were reversed by CAR. Mechanistically, we demonstrated that CAR inhibited nuclear factor kappa B (NF-κB) signaling by activating the nuclear factor erythroid-derived 2-like 2 (Nrf2) in IL-1β-induced rat NP cells. Furthermore, the protective effect of CAR was shown in the IVDD model through persistent intragastric administration. Taken together, our results revealed that CAR could activate the Nrf2/HO-1 signaling axis and be a novel agent for IVDD therapy.

Nonlocality is a key feature of quantum theory and is reflected in the violation of Bell inequalities for entangled systems. The experimental tests beyond the electromagnetism and massless quanta are of great importance for understanding the nonlocality in different quantum interactions. In this work, we develop a generalized Clauser-Horne inequality pertaining especially to the high energy physics processes, which is quantum mechanical intervene free. We find, in the process of pseudoscalar quarkonium exclusive decay to entangled $\Lambda\bar{\Lambda}$ pairs, the inequality could be violated and is verifiable in high energy experiments, like BES III or BELLE II., Comment: 13 pages, 1 figure

The uncertainty principle lies at the heart of quantum physics, and is widely thought of as a fundamental limit on the measurement precisions of incompatible observables. Here we show that the traditional uncertainty relation in fact belongs to the leading order approximation of a generalized uncertainty relation. That is, the leading order linear dependence of observables gives the Heisenberg type of uncertainty relations, while higher order nonlinear dependence may reveal more different and interesting correlation properties. Applications of the generalized uncertainty relation and the high order nonlinear dependence between observables in quantum information science are also discussed., Comment: 26 pages, 3 figures; published in Ann. Phys. (Berlin)

The Leggett inequality is a constraint on the bipartite correlation that admits certain types of non-localities. Existing tests mainly focused on the electromagnetic systems where measurement apparatus are assumed to be projective and sharp. However, in nature there are interactions that do not obey the same conservation laws for photon, and the actual measurements may subject to unavoidable uncertainties due to the fundamental physical principles. In this work, we generalize the Leggett inequality to incorporate the measurements that are unsharp and/or biased. It is found that the parity violation in nature provides a spontaneous implementation of an unsharp measurement for the spin of hyperon. A fine structured Leggett inequality for hyperon decays characterized by the asymmetry parameters is obtained and its violation is found which could be observed with the yet obtained data in experiment, like BESIII and Belle., Comment: 22 pages, 7 figures; published in Phys. Rev. D

Transition metal phosphides (TMPs) have the advantages of large theoretical capacity, good thermal stability and low cost, are widely concerned as potential electrode materials for lithium ion battery (LIBs). Herein, a mild method was used to load CoP on graphene oxide to prepare porous CoP@RGO materials. The CoP@RGO exhibits an excellent electrochemical performance due to its good porosity and excellent electronic conductivity. The initial discharge specific capacity of the CoP@RGO electrode reaches 1210 mAh g−1, and after 50 cycles, the discharge specific capacity still reaches 745 mAh g−1. The outstanding performance of the CoP@RGO provides not only a novel insight into the modulated volume expansion of anode but also one of the most effective strategies for large-scale production of graphene-loaded new phosphide electrodes. The pseudocapacitance-controlled charge storage contributions of 80.2% at 0.8 mV s−1 sweep rates, which shows it exhibits higher pseudocapacitance -controlled charge storage contributions.

The uncertainty relation, as one of the fundamental principles of quantum physics, captures the incompatibility of noncommuting observables in the preparation of quantum states. In this work, we derive two strong and universal uncertainty relations for $N(N\ge2)$ observables with discrete and bounded spectra, one in multiplicative form and the other in additive form. To verify their validity, for illustration, we implement in the spin-1/2 system an experiment with single-photon measurement. The experimental results exhibit the validity and robustness of these uncertainty relations, and indicate the existence of stringent lower bounds., Comment: 9 pages, 5 figures. Slightly extended

Taking advantage of coherent light beams, we experimentally investigate the variancebased uncertainty relations and the optimal majorization uncertainty relation for the two-dimensional quantum mechanical system.Different from most of the experiments which devoted to record each individual quantum, we examine the uncertainty relations by measuring an ensemble of photons with two polarization degree of freedom characterized by the Stokes parameters which allow us to determine the polarization density matrix with high precision. The optimality of the recently proposed direct-sum majorization uncertainty relation is verified by measuring the Lorenz curves. Results show that the Lorenz curve method represents a faithful verification of the majorization uncertainty relation and the uncertainty relation is indeed an ensemble property of quantum system., Comment: 7 pages, 7 figures

Employing the lattice theory on majorization, we investigate the universal quantum uncertainty relation for any number observables and general measurement. We find: 1. The least bounds of the universal uncertainty relations can only be properly defined in the lattice theory; 2. Contrary to variance and entropy, the metric induced by the majorization lattice implies an intrinsic structure of the quantum uncertainty; 3. The lattice theory correlates the optimization of uncertainty relation with the entanglement transformation under local quantum operation and classical communication. Interestingly, the optimality of the universal uncertainty relation is found can be mimicked by the Lorenz curve, initially introduced in economics to measure the wealth concentration degree of a society., Comment: 25 pages, 2 figures; published in Ann. Phys. (Berlin)

This paper studies how the purchase of insurance policies against epidemic security risks, a voluntary strategy of individuals, impacts the controlling of epidemic security risk propagation in networks and the profit of the insurer. For this purpose, we first formulated a modified agent-based framework that characterizes the coupled dynamics of individual security-protection investment behaviors and epidemic security risk propagation process, to study the effectiveness of insurance policies. Second, we proposed a novel insurance policy that follows the designed “precaution and dynamic post-indemnity” (PDPI) principle, taking the correlated and interdependent characteristics of epidemic security risks into account. We determined how the PDPI insurance policy affects security-protection investment coverage and epidemiological dynamics by tuning the allocation coefficient of insurance funds α and the ratio between the premium and the cost of investment R. The results indicated that, although insurance policies have negative influences on voluntary investment behaviors, the risk propagation can be controlled effectively by appropriate combination of α and R, because the precaution mechanism in the PDPI insurance policy can counteract this side effect by guaranteeing the security-protection investment coverage among insured individuals with larger degrees. We further found that, although the insurance policy cannot lead to the maximal profit when the policy has the best performance on risk propagation prevent, the insurer still can earn positive profits. Finally, some effective PDPI insurance policies against specific investment costs are given. The models and findings shed new and meaningful insights into designing and measuring effective insurance policies associated with security-protection investment in controlling the propagation of epidemic security risks.

A series of 1-sulfonyl-1-trifluoromethyl allenes were prepared for the first time from commercial available 2-bromo-3,3,3-trifluoropropene. Cycloaddition reaction of these trifluoromethylated allenes with nitrones occured readily under mild conditions, giving the corresponding trifluoromethylated isoxazolidines in high yields.

Uncertainty principle is an inherent nature of quantum system that undermines the precise measurement of incompatible observables and hence the applications of quantum theory. Entanglement, another unique feature of quantum physics, was found may help to reduce the quantum uncertainty. In this paper, we propose a practical method to reduce the one party measurement uncertainty by determining the measurement on the other party of an entangled bipartite system. In light of this method, a family of conditional majorization uncertainty relations in the presence of quantum memory is constructed, which is applicable to arbitrary number of observables. The new family of uncertainty relations implies sophisticated structures of quantum uncertainty and nonlocality, that were usually studied by using scalar measures. Applications to reduce the local uncertainty and to witness quantum nonlocalities are also presented., 24 pages, 4 figures; published in Adv. Quantum Technol

Scientific Reports 7: Article number: 44764; published online: 20 March 2017; updated: 25 May 2018 This Article contains errors in the following equations: In Equation 7, should read: In Equation 9, should read: In Equation 10, should read: In Equation 16, should read: In Equation 17, should read

Entanglement is a unique nature of quantum theory and has tremendous potential for application. Nevertheless, the complexity of quantum entanglement grows exponentially with an increase in the number of entangled particles. Here we introduce a quantum state concentration scheme which decomposes the multipartite entangled state into a set of bipartite and tripartite entangled states. It is shown that the complexity of the entanglement induced by the large number of particles is transformed into the high dimensions of bipartite and tripartite entangled states for pure quantum systems. The results not only simplify the tedious work of verifying the (in)equivalence of multipartite entangled states, but also are instructive to the quantum many-body problem involving multipartite entanglement., Comment: 16 pages, 1 figure; published in Phys. Rev. A

The uncertainty relation is a distinguishing feature of quantum theory, characterizing the incompatibility of noncommuting observables in the preparation of quantum states. Recently, many uncertainty relations were proposed with improved lower bounds and were deemed capable of incorporating multiple observables. Here we report an experimental verification of seven uncertainty relations of this type with single-photon measurements. The results, while confirming these uncertainty relations, show as well the relative stringency of various uncertainty lower bounds., slightly extended. To appear in PRA

Two metal-organic frameworks, [Co2(ABTC)(bimh)(OH)]·2H2O (1) and [Co3(ABTC)2(dimb)4]n (2) [H3ABTC = 3,4′,5-azobenzenetricarboxylic acid, bimh = 1,1′-(1,4-hexanediy)bis(imidazole), dimb = 1,4-bis(1H-imidazol-1-yl)benzene], were prepared under solvothermal conditions and structurally characterized. Complex 1 demonstrates a complicated 3D (3,8)-connected tfz-d net with (43)2(46.617.85) topology. The framework of 2 can be classified as a rare 3D (3,6,6)-connected net with the Schafli symbol of (4.62)2(42.610.83)(44.610.8), and exhibits an intriguing self-penetrating motif. Meanwhile, the thermal stabilities and magnetic properties for 1 and 2 were also probed.

The transformation of hydroxyl group in benzyl or allyl alcohols to trifluoromethyl was achieved via the reaction of the corresponding alkyloxydiphenylphosphine and CuCF3, generated in situ from methyl fluorosulfonyldifluoroacetate and CuI, under mild conditions. A plausible mechanism was proposed on the basis of experimental results.

In this study, we investigate whether bone marrow mononuclear cells (BM-MNC) or peripheral blood mononuclear cells (PB-MNC) have therapeutic efficacy in type 2 diabetes (T2D).Search terms included stem cell, bone marrow cell, peripheral blood cell, umbilical cord blood and T2D in MEDLINE, the Cochrane Controlled Trials Register, EMBASE, the Wanfang Database, the China Science and Technology Periodical Database and China Journal Net.Fifteen trials met our inclusion criteria (n = 497). One group included 266 cases with BM-MNC therapy and the other group contained 231 cases with PB-MNC treatment. Glycosylated hemoglobin was decreased after BM-MNC or PB-MNC therapy compared with that before (12 months: P0.001; 6 months: P0.001; 3 months: P0.05). Fasting plasma glucose was reduced in BM-MNC therapy group compared with control after 12-month follow-up (P0.001) and after BM-MNC therapy compared with that before (9 months: P0.001) but was not obvious in other stages. Meanwhile, the analysis showed that C-peptide level increased after BM-MNC and PB-MNC therapy compared with the control therapy (12 months: P0.001) and with that before therapy (6 months: P0.05). Insulin requirement reduction was also observed in patients receiving BM-MNC therapy (3, 6, 9 and 12 months: P0.05).To a certain extent, BM-MNC or PB-MNC therapy for T2D demonstrated superiority of glycemic control, increased insulin biosynthesis and elevated insulin secretion from existing β-cells and might prevent islet cell loss.

Curcumin, extracted from South Asian spice turmeric, has been determined to have the promising ability in antioxidation and anti-inflammation. However, the effect of curcumin on treating brain damage has been not reported. In this article, the aim was to evaluate the effect of curcumin on cell apoptosis in rats exposed to hypoxia-hypercapnia and explore the therapeutic potential of curcumin in hypoxia-hypercapnia brain damage (HHBD). Sprague Dawley rats were randomly assigned into 3 groups: control group, hypoxia-hypercapnia group and curcumin group. The Fas/FasL expressions in HHBD rats treated by curcumin were measured by immunohistochemical staining and western blotting. The pathological changes of brain cells were observed by transmission electron microscope. Rats with HHBD showed significant increase of Fas/FasL expression and ultrastructural changes in brain tissue cells. Curcumin intervention effectively reversed the Fas/FasL-mediated apoptosis and HHBD-induced brain edema. Curcumin may be a potential therapeutic alternative for HHBD.

Based on the existing form of Zn2SiO4 in willemite, the chemical precipitation method was used to synthesize Zn2SiO4. Through the orthogonal experimentation, the reaction conditions of melten NaOH decomposing Zn2SiO4 were optimized, and the optimal experimental conditions include reaction temperature of 400 °C, reaction time of 4 h, and alkaline-to-ore molar ratio of 20:1. Based on the optimized experiment, on-line detection for the alkali leaching was made by using Raman spectroscopy; XRD was used to analyze the structure of water leaching residue, to explore the reaction mechanism of NaOH decomposing Zn2SiO4. The results show that during the reaction process, the Si-O bond in SiO4 is destroyed, and the NaOH inserts itself into the silicate lattice, producing an immediate Na2ZnSiO4 product. After the alkali leaching process, Zn2+ can be separated from the SiO4 array, which can be released out of the silicate in the form of ZnO.

A novel and practical reaction for the direct intramolecular oxidative coupling of butenylated arenes is reported. With the catalysis of Pd(OAc)2, reactions of various butenylated arenes and carboxylic acids with Selectfluor reagent in CH3CN solution afforded the corresponding monocarboxylation/cyclization products in good yields under mild conditions. This research demonstrated an economic method with the synthesis of 2-tetralyl carboxylic esters, a valuable class of bioactive compounds.

A new sesquiterpenoid glycoside, called speciosaoside A ( 1 ), and a known sesquiterpenoid glycoside, (1′R,3′R,5′R,8′S)-epi-dihydrophaseic acid β-D-glucoside ( 2 ), were isolated from the fruits of Chaenomeles speciosa (Sweet) Nakai (Rosaceae) using column chromatography and preparative HPLC. The structure of compound 1 was deduced from comprehensive spectroscopic analysis including IR, HR-ESI-MS, 1D NMR, and 2D NMR. The structure of compound 2 was identified by comparison of its spectral data with those reported in the literature.

The uncertainty relation is one of the key ingredients of quantum theory. Despite the great efforts devoted to this subject, most of the variance-based uncertainty relations are state-dependent and suffering from the triviality problem of zero lower bounds. Here we develop a method to get uncertainty relations with state-independent lower bounds. The method works by exploring the eigenvalues of a Hermitian matrix composed by Bloch vectors of incompatible observables and is applicable for both pure and mixed states and for arbitrary number of N- dimensional observables. The uncertainty relation for incompatible observables can be explained by geometric relations related to the parallel postulate and the inequalities in Horn's conjecture on Hermitian matrix sum. Practical entanglement criteria are also presented based on the derived uncertainty relations., 15 pages, no figures

As an effective tool to build interpretive models, variable selection plays an increasingly important role in high-dimensional data analysis. It has been proven that ensemble learning can significantly improve selection accuracy, alleviate the instability of traditional selection methods, and reduce false discovery rate (FDR). Therefore, variable selection ensembles (VSEs) have gained much interest in recent years. Stability selection [1], a VSE technique based on subsampling in combination with a base algorithm like lasso, is an effective method to control FDR and to improve selection accuracy in linear regression models. In this paper, we apply it to handle variable selection problems in a Cox model. Some simulated data with various censoring rates are used to study the influence of one parameter Amin in stability selection to its performance. In the meantime, stability selection is compared with other variable selection approaches. The experimental results demonstrate its good performance.

The expression of keratinocyte growth factor-1 (KGF-1) and keratinocyte growth factor-2 (KGF-2) in skin wounds in mice was studied using multiple methods. The dynamic expression of KGF-1 and KGF-2 for antemortem and postmortem injuries as well as the examination of antemortem injuries after death under different temperature and over varying time periods was studied. It demonstrates that skin KGF-1 resulting from an antemortem injury starts to rise at 6 hours, reaches its peak at 1 day, and starts to drop at 5 days. The expression of skin KGF-2 resulting from an antemortem injury starts to rise at 12 hours, reaches its peak at 7 days, and begins to drop at 10 days. Skin KGF-1 and skin KGF-2 after death stabilize within 7 days at 4°C and -20°C, within 5 days at 20°C, and within 1 day at 30°C. The application of KGF-1 and KGF-2 indicators in skin wound age determination is both feasible and reliable.