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This study constructs a multi-factor capital asset pricing model (CAPM) to analyze systematic risk and other influential risk factors in the silver futures exchange-traded funds (silver futures ETFs) market and then provides an analysis of precious metals investments as a reference. Specifically, the volatility index (VIX) and the real estate investment trusts (REITs) are used as influences of silver futures on political and economic factors. In addition, we use text mining to capture news events on the network into a Boolean matrix, which transforms unstructured data into structured data. Further, the term frequency (TF) and inverse document frequency (IDF) algorithm are applied to calculate the most important keywords on the market and measure them in the model after a sentimental evaluation. The empirical results show that the silver futures ETFs market is indeed affected by market news, providing investors in this market with a reference. JEL classification numbers: C10, C13, G00, G10. Keywords: Silver futures ETFs, Volatility index; Real estate investment trusts, Text mining, Inverse document frequency.

With the global warming, the harm of heat stress (HS) to the breeding industry has become more common, which causes the decline of animal production performance and low immunity. This study aimed to analyze the effect of HS on the intestinal immune function of Salmonella-infected chickens. Fourteen-day-old broilers were divided into the following four groups of eight replicates: control (Control), heat stress (HS), Salmonella Typhimurium (ST), and heat stress + Salmonella Typhimurium (HS+ST). The broilers were subjected to a heat stress of 35 °C from 15 to 28 days of age. Salmonella Typhimurium (ST, 14028, 109 cfu/mL) was inoculated, via oral administration at 29 days of age, into ST and HS+ST group birds. On the 4th day after Salmonella Typhimurium administration, an increase in jejunum IgA levels was observed in chickens infected with Salmonella Typhimurium. Mechanistic regulation of TLR4-NFκB-NLRP3 and TLR4-TBK1 signaling by heat stress was evaluated in Salmonella Typhimurium–infected broilers. Heat stress markedly inhibited the expression of cytokines including TNF-α, IL-6, IL-1β, NLRP3, caspase-1, NF-κB-p65, and p-NF-κB-p65, and the TLR4-TBK1 cytokines IFN-α, IFN-γ, p-IRF3, and p-TBK1 in jejunum of broilers infected with Salmonella Typhimurium. Collectively, our results demonstrate that heat stress can inhibit intestinal immune response by downregulating the expression of TLR4-NFκB-NLRP3 and TLR4-TBK1 signaling pathways in broilers infected with Salmonella Typhimurium.

Shenling Baizhu San has beneficial effects on the metabolism of the gut microbiota, however, the mechanisms underlying microbiota metabolites mediated anti-inflammation signaling are not well understood. Previously, we have demonstrated that supplementation with Shenling Baizhu San alleviated antibiotic-associated diarrhea (AAD). The current study intends to investigate the dynamic modulation of Shenling Baizhu San polysaccharides (SP) on colitis from the gut microbiota metabolites perspective. Administration of SP effectively relieved colitis induced by DSS in mice, including alleviating body weight loss, the downregulation of colon proinflammatory mediators, and the promotion of intestinal injury repair. Whereas, the efficacy was eliminated by antibiotics, which demonstrated that the efficacy of SP was dependent on the gut microbiota. Fecal microbiota transplantation (FMT) showed that the efficacy of SP can be transferred to gut microbiota. Serum metabolomics analysis showed that supplementation with SP significantly promoted tryptophan metabolism, which was consistent with the changed structure of the gut microbiota, including Bacteroides, Bifidobacterium and Ruminococcus regulated by SP. Especially, the tryptophan metabolites-kynurenine (KYN) activated the expression of amplifying aryl-hydrocarbon receptor (AhR) and Cyp1A1 to promote IL-10 expression in colon. These data suggested that SP positively affected colitis in mice by regulating tryptophan metabolic function of their gut microbiota.

Osteosarcoma (OS) is a common type of malignant bone tumor in adolescents with high risk of metastasis. However, the clinical management still remains unsatisfactory. Traditional Chinese medicine (TCM) has been widely considered as an alternative treatment, and their extracts have proved to possess great potential for drug discovery. Baicalein (BA), the active pharmaceutical ingredient ofThe potential anti-cancer effects on cell growth, cell cycle, apoptosis and migration were examined in OS cells. Moreover, the lncRNA-Neighboring Enhancer of FOXA2 (lncRNA-NEF) and Wnt/β-catenin signaling were detected by qPCR and Western blotting assays. TheIn the present study, BA was found to significantly suppress tumor growthIn conclude, our results demonstrated that BA suppressed tumor growth and metastasisThe findings derived from this study validates the anti-cancer activity of BA in OS and provides a novel underlying mechanism, which suggest that BA may be a potential candidate to develop the effective drug for OS patients.

Heat stress can decrease poultry performance indices, immune function, and intestinal development, which can reduce birds' innate protective mechanisms and may be more susceptible for pathogens. Ma chickens heat-stressed with 41°C for 12 h and recovered for 7 d had extremely low immunity. In this study, a susceptible chicken model induced by heat stress and then infected with Escherichia coli O157:H7 was established to explore the mechanisms of birds' intestinal immune function changes. Ma chickens in heat stress + E. coli (HS + E. coli) group were stressed at 41°C for 12 h and recovered for 7 d, then chickens in E. coli group and HS + E. coli group were orally administered with 1 mL E. coli O157:H7 (1 × 109 cfu/mL). Chickens were sacrificed at the fourth day after E. coli administration. Results showed that the HS + E. coli group had increased intestinal length and weight, had higher E. coli counts in cecum contents than the E. coli group. Heat stress also enhanced serum diamine oxidase and decreased IgA level in chickens infected by E. coli. Heat stress had protective effects in small intestinal morphology except for duodenum by using hematoxylin and eosin staining. Compared with the E. coli group birds, IL-1β, TNF-α, and caspase-1 protein levels in the duodenum and ileum were significantly increased. Heat stress also can significantly enhance the gene and protein expression of Hsp70, TLR4, and NF-κB in the duodenum and ileum, respectively. The gene expression of Hsp70, TLR4, and NF-κB in the jejunum was not influenced, but the protein expression of Hsp70 and NF-κB was inhibited by heat stress. The results indicated heat stress can amplify the effect of E. coli on intestinal inflammatory injury of Ma chickens through increasing TLR4-NF-κB signaling pathway.

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High ambient temperature has potential influence on oxidative stress, or systemic inflammation affecting poultry production and immune status of chickens. Heat stress (HS) induces intestinal inflammation and increases susceptibility of harmful pathogens, such as Salmonella and Escherichia coli. Intestinal inflammation is a common result of body immune dysfunction. Therefore, we designed an experiment to analyze the effects of 35 ± 2 °C HS on salmonella infection in chickens through regulation of the immune responses. 40 broiler chickens were randomly divided into 4 groups: control group, heat stress (HS) group, salmonella typhimurium (ST) group and model group (heat stress + salmonella typhimurium, HS + ST). Birds in HS and model group were treated with 35 ± 2 °C heat stress 6 h a day and for 14 continuous days. Then, ST and model group birds were orally administrated with 1 mL ST inoculum (109 cfu/mL). Chickens were sacrificed at the 4th day after ST administration and ileum tissues were measured. We observed that heat stress decreased ileum TNF-α and IL-1β protein expressions. Concomitantly heat stress decreased NLRP3 and Caspase-1 protein levels. The protein expressions of p–NF–κB-p65 and p-IκB-α in ileum. Heat stress also inhibited IFN-α, p-IRF3 and p-TBK1, showing a deficiency in the HS + ST group birds. Together, the present data suggested that heat stress suppressed intestinal immune activity in chickens infected by salmonella typhimurium, as observed by the decrease of immune cytokines levels, which regulated by NF-κB-NLRP3 signaling pathway.

Profile monitoring has been recently considered as one of the most promising areas of research in statistical process monitoring (SPM). It is a technique for monitoring the stability of a functional relationship between a dependent variable and one or more independent variables over time. The monitoring of linear profiles is the most popular one because the relationship between the dependent variable and the independent variables is easy to describe by linearity, in addition to its flexibility and simplicity. Furthermore, almost all existing charting schemes for monitoring linear profiles assume that error terms are normally distributed. In some applications, however, the normality assumption of error terms is not justified. This makes the existing charting schemes not only inappropriate but also less efficient for monitoring linear profiles. In this article, based on the spatial rank-based regression, we propose a charting method for monitoring linear profiles where the error terms are not normal...

Bimolecular reaction rate coefficients (kOH) for reaction of hydroxyl radicals (OH) with adipic, pimelic, suberic, azelaic, sebacic and cis-pinonic acids were measured in aqueous phase for the neutral (pH = 2) and completely deprotonated (pH = 9) forms of the acids listed. Reactions were carried out in bulk solution between 283 and 318 K. Camphoric acid was used as a reference compound for measuring kOH values using a relative rate method, and with hydrogen peroxide (H2O2) as a photochemical source of OH. Concentrations of the reactants were monitored with liquid chromatography coupled with electrospray tandem mass spectrometry (LC-ESI/MS2). The kOH values measured were between 1 and 8 × 10-9 M-1s-1; only adipic and pimelic acids showed a significant pH-dependence to their OH reactivity. The kinetic data acquired and the data reported in the literature for camphoric, glutaric and succinic acids were used to optimize new structure-activity relationship (SAR) parameters. The SAR developed here allowed accurate prediction of kOH values for aliphatic carboxylic acids in the temperature range between 283 and 318 K. The accuracy of the developed SAR was evaluated against the experimental kOH values measured in this work and obtained from the literature data. Moreover, this work is the first to accurately predict the temperature-dependent kOH values for carboxylic acids.

The Ni(Pt)/Si-cap/SiGe silicidation process has been optimized by modulating the Si-cap layer thickness and a cold Si preamorphization implantation (PAI), which effectively reduces the sheet resistance (Rs). In addition, it is revealed that PAI can obviously increase the Ni(Pt)Si grain size for a lower Rs.

Fault location is an effective way to ensure quickly power recovery after a failure in power distribution system. Bad operation environment of FTU, damaged elements or lost information usually cause variations in fault information for correlation analysis in fault location of power distribution system. A data mining (DM) correlation analysis model based on rough sets (RS) theory and immune algorithm (IA) is proposed in this paper. Firstly, using RS theory to extract domain knowledge, a set of the given variant fault pattern is converted into a decision table in RS. Secondly, an attribute reduction of the decision table is made by using the IA theory, and the intrinsic correlation rules between input vector (condition attribute) and output vector (decision attribute) are mined. Then, the data mining method is used to deal with the distortion of FTU real-time input information. According to the current limit information sequence of section switches, line fault states in each section are judged to realize the fault location in power distribution network. Finally, the feasibility and effectiveness of the fault location model of distribution network based on RS-IA data mining model is verified by simulation.

In recent years ferroelectric polymers have attracted much attention due to their potentials in flexible electronics. To satisfy the requirements of low operation voltage and low power consumption, it is required to reduce the ferroelectric film thickness down to, for example, 100 nm. However, decreased film thickness results in low crystallinity and thus worse electrical performance. One possible solution is to realize the epitaxial growth of ferroelectric thin films via effective control of structure and orientation of ferroelectric crystals. Here we report our work on poly(tetrafluoroethylene)-template-induced ordered growth of ferroelectric thin films. We focus on the study of thermal stability of ferroelectric phase in these ferroelectric films. Our work indicates that epitaxial growth effectively increases the crystallinity and the melting and ferroelectric phase transition temperatures and implies the extended application of ferroelectric devices at higher temperature.

Based on the contact fretting fatigue theory and fatigue tests, the fastener fatigue fracture mechanism of composite large interference fit connection was conducted in this paper. Test results showed that the fatigue fracture mode of composite mechanical connections in large interference fit (1.8% and 3%) were fastener fatigue fracture. Under the impact of cyclic load, fastener fretting wear and damage type of fretting fatigue were generated between blind bolted fastener and composite hole. According to the theory of fretting white layer, the failure mechanism of fastener fatigue fracture was explored, which provided theoretical basis and experimental basis for the design of mechanical connected structure with higher fatigue life.

The significant thermal stability improvement induced by laser annealing (LA) is demonstrated for 50-A Ni(Pt) film silicidation. For the first time, it is revealed that LA may induce less stress in ultrathin Ni(Pt)Si film during silicidation, which can directly improve the thermal stability of the film. The local area annealing model is proposed to discuss the origin of stress relief. Besides, it is discovered that LA can result in a higher Pt concentration at the Ni(Pt)Si film surface, which will also enhance the resistance of Ni(Pt)Si film agglomeration.

Two miniature inverted-repeat transposable elements (MITEs), MCLas-A and MCLas-B, were recently identified from ‘ Candidatus Liberibacter asiaticus’ known to be associated with citrus Huanglongbing (HLB, yellow shoot disease). MCLas-A was suggested as an active MITE because of its mobility. The immediate upstream gene of the two MITEs was predicted to be a putative transposase. The goal of this study is to analyze the sequence variation in the upstream putative transposase of MITEs and explore the possible correlation between sequence variation of transposase gene and MITE activity. PCR and sequence analysis showed that 12 sequence types were found in six major amplicon types from 43 representative ‘Ca. L. asiaticus’ isolates from China, the United States and Brazil. Out of the 12 sequence types, three (T4, T5-2, T6) were reported for the first time. Recombination events were found in the two unique sequence types (T5-2 and T6) which were detected in all Brazilian isolates. Notably, no sequence variation or recombination events were detected in the upstream putative transposase gene of MCLas-A, suggesting the conservation of the transposase gene might be closely related with the MITE activity. Phylogenetic analysis demonstrated two well supported clades including five subclades were identified, clearly reflecting the geographical origins of isolates, especially that of Ruili isolates, Sao Paulo isolates and a few Florida isolates.

β-adrenergic receptor blockers (β-blockers) are widely detected in the aquatic environment; however, the effects of these pharmaceuticals on aquatic organisms remain uncertain. In this study, adult zebrafish were exposed to two different β-blockers, propranolol and metoprolol, for 96 h. After exposure, the transcriptional responses of genes encoding the β-adrenergic receptor (i.e., adrb1, adrb2a, adrb2b, adrb3a and adrb3b), genes involved in detoxification and the stress response (i.e., hsp70, tap, mt1 and mt2), and genes related to the antioxidant system (i.e., cu/zn-sod, mn-sod, cat and gpx) were examined in the brain, liver and gonad. Our results show that both propranolol and metoprolol exposure changes the mRNA level of β-adrenergic receptors, indicating clear pharmacological target engagement of the β-blockers. The transcription of genes related to antioxidant responses and detoxification process were induced, suggesting that β-blocker exposure can activate the detoxification process and result in oxidative stress in fish. Moreover, the transcriptional responses displayed substantial tissue- and gender-specific effects. Considering the environmental concentrations of propranolol and metoprolol, these results suggest that these pharmaceuticals are unlikely to pose a risk to fish. However, the impacts in prolonged exposure, along with other possible side effects due to β-adrenergic receptor blockade, should be further assessed.

Organic semiconducting/ferroelectric blend films attracted much attention due to their electrical bistability and rectification properties and thereof the potential in resistive memory devices. During film deposition from the blend solution, spinodal decomposition induced phase separation, resulting in discrete semiconducting phase whose electrical property could be modulated by the continuous ferroelectric phase. However, blend films processed by common spin coating method showed extremely rough surfaces, even comparable to the film thickness, which caused large electrical leakage and thus compromised the resistive switching performance. To improve film roughness and thus increase the productivity of these resistive devices, we developed temperature controlled spin coating technique to carefully adjust the phase separation process. Here we reported our experimental results from the blend films of ferroelectric poly(vinylidene fluoride-trifluoroethylene (P(VDF-TrFE)) and semiconducting poly(3-hexylthiophene) (P3HT). We conducted a series of experiments at various deposition temperatures ranging from 20 to 90 °C. The resulting films were characterized by AFM, SEM, and VPFM to determine their structure and roughness. Film roughness first decreased and then increased with the increase of deposition temperature. Electrical performance was also characterized and obviously improved insulating property was obtained from the films deposited between 50 and 70 °C. By temperature control during film deposition, it is convenient to efficiently fabricate ferroelectric/semiconducting blend films with good electrical bistability.