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Abstract: In this study we have investigated the antagonist affinity, efficacy and duration of action of bencycloquidium bromide (BCQB), a selective muscarinic M3 receptor antagonist, as a possible clinical bronchodilator for the treatment of chronic obstructive pulmonary disease (COPD) and asthma. In competition studies, BCQB showed high affinity toward the M3 receptor in Chinese hamster ovary (CHO) cells (M3 pKi=8.21, M2 pKi=7.21, and M1 pKi=7.86); pA2 =8.85, 8.71 and 8.57 in methacholine-induced contraction of trachea, ileum and urinary bladder, 8.19 in methacholine-induced bradycardia of right atrium in vitro, respectively. In function studies, duration of inhibition of carbachol-induced tonic contraction, BCQB and ipratropium had a very similar onset and offset of action, but onset faster and offset slower than that of tiotropium. After treatment with intratracheally instilled or the inhalation route, BCQB protects against methacholine or antigen-induced bronchoconstriction in a dose-dependent manner in the normal and sensitized guinea pigs in vivo. BCQB and ipratropium-induced inhibitory activity was short lasting, as it declined quickly when compared to tiotropium. These results suggest that BCQB bind muscarinic M3 receptors with high affinity. On this basis we speculate that a putative BCQB-based therapy for COPD might require more than once-a-day administration to be as effective as the currently employed once-daily therapy with tiotropium. Nevertheless, Inhalable M3-selective compounds may spare M2-cardiac receptors and reduce the risks of cardiovascular events associated with the long-term treatment of these agents. [Copyright &y& Elsevier]

This study proposes a new SL LDMOS structure similar to a silicon-on-insulator. The P+/N structure is used to replace the buried oxygen layer of traditional SOI LDMOS devices. The N-type layer is made of SiC material, and the highly doped P-type layer is used to partially deplete the SiC layer to achieve the SOI Like effect. At the same time, the highly doped buried layer is formed by ion implantation in the SiC layer to adjust the electric field in the drift region and improve the breakdown voltage. The Silvaco TCAD software is used to conduct a two-dimensional simulation of the proposed structure. The breakdown voltage of the device is 306 V. Compared with the SOI LDMOS under the same withstand voltage, the proposed SL LDMOS has about 32.9% lower the on-resistance and better electrical characteristics. In the study of radiation effects, the burnout threshold of the proposed structure is LET = 0.93 pC/μm and V d = 222 V, which shows that the device has good anti-single event burnout performance. In the study of the total-ionizing-dose, when the total dose is higher than 119 Krad(Si), the breakdown voltage of the proposed device is significantly higher than that of the SOI LDMOS device. This can effectively address the shortcomings of SOI LDMOS devices regarding the total-ionizing-dose. Therefore, the proposed structure is suitable for application in harsh environments such as those with high radiation. • The high doped P-type layer can deplete the low doped n-type layer(4H-SiC), realize the effect of buried oxygen layer. • Adjusting the electric field in the drift region by using highly doped SiC buried layer. • The burnout threshold of the structure is LET = 0.93 pC/μm and V d = 222 V. The TID does not affect the BV. [ABSTRACT FROM AUTHOR]

This paper describes a single-event burnout (SEB) simulation for a conventional GaN MISFET field plate (FPC-MISFET) and a MISFET with an embedded pn junction (EJ-MISFET). The SEB triggering mechanism is affected by impact ionization. The electrons, which are induced by heavy ion exposure, can rapidly move to the drain, which leads to strong impact ionization around the drain. Compared to the FPC-MISFET, both the peak electric field and the impact ionization around the drain are reduced in the GaN MISFET with the embedded pn junction. The proposed EJ-MISFET also shows improved SEB performance. For a heavy ion, with a linear energy transfer (LET) of 0.6 pC/μm (hitting the devices) vertically, the SEB threshold voltages for the FPC-MISFET and EJ-MISFET are 520 and 760 V, respectively. Unlabelled Image • The SEB performance of GaN MISFET with embedded pn junction is investigated. • Compared to conventional GaN MISFET, the SEB threshold voltage in proposed GaN MISFET is enhanced by 46%. • The improvement of SEB performance is due to embedded pn junction. [ABSTRACT FROM AUTHOR]

In the title compound, C31H34O8, the three benzene rings are nearly perpendicular to each other. The six-membered mannopyranoside ring displays a typical chair conformation. Intermolecular C—H...O hydrogen bonding helps to stabilize the crystal structure. [ABSTRACT FROM AUTHOR]

Background: Sentinel lymph node metastasis (SLNM) is a critical factor in the prognosis and treatment planning for breast cancer (BC), as it indicates the potential spread of cancer to other parts of the body. The accurate prediction and diagnosis of SLNM are essential for improving clinical outcomes and guiding treatment decisions., Objective: This study aimed to construct a Lasso regression model by integrating multimodal ultrasound (US) techniques, including US, shear wave elastography (SWE), and contrast-enhanced ultrasound (CEUS), to improve the predictive accuracy of sentinel lymph node metastasis in breast cancer and provide more precise guidance for clinical treatment., Results: A total of 253 eligible samples were screened, of which 148 were group benign and 105 were group malignant. There were statistically significant differences ( p < 0.05) between group malignant patients in terms of age, palpable mass, body mass index, distance to nipple, maximum diameter, blood flow, microcalcification, 2D border, 2D morphology, and 2D uniformity and group benign. The Lasso regression model was useful in the diagnosis of benign and malignant nodules with an AUC of 0.966 and in diagnosing SLNM with an AUC of 0.832., Conclusion: In this study, we successfully constructed and validated a Lasso regression model based on the multimodal ultrasound technique for predicting whether SLNM occurs in BCs, showing high diagnostic accuracy., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2024 Li, Chen, Liu, Bao, Zhang and Xu.)

Carabranolides present characteristic NMR resonances for the cyclopropane moiety, which distinctly differ from those of other compounds and were used for an NMR-guided isolation in this study. As a result, 11 undescribed carabranolides ( 1 - 11 ), along with five known ones ( 12 - 16 ), were isolated from the fruits of Carpesium abrotanoides L. Compounds 1 - 11 are new esters of carabrol at C-4 with different carboxylic acids. Their structures were elucidated by HRESIMS and NMR spectroscopic data analysis. The biological evaluation showed that compounds 2 - 4 , 15 , and 16 exhibited significant inhibitory activity against LPS-induced NO release with an IC 50 value of 5.6-9.1 μM and dose-dependently decreased iNOS protein expression in RAW264.7 cells.

Olibanum, a golden oleo-gum resin from species in the Boswellia genus ( Burseraceae family), is a famous traditional herbal medicine widely used around the world. Previous phytochemical studies mainly focused on the non-polar fractions of olibanum. In this study, nine novel diterpenoids, boswellianols A-I ( 1 - 9 ), and three known compounds were isolated from the polar methanolic fraction of the oleo-gum resin of Boswellia carterii . Their structures were determined through comprehensive spectroscopic analysis as well as experimental and calculated electronic circular dichroism (ECD) data comparison. Compound 1 is a novel diterpenoid possessing an undescribed prenylmaaliane-type skeleton with a 6/6/3 tricyclic system. Compounds 2 - 4 were unusual prenylaromadendrane-type diterpenoids, and compounds 5 - 9 were new highly oxidized cembrane-type diterpenoids. Compounds 1 and 5 showed significant transforming growth factor β (TGF- β ) inhibitory activity via inhibiting the TGF- β -induced phosphorylation of Smad3 and the expression of fibronectin and N-cadherin (the biomarker of the epithelial-mesenchymal transition) in a dose-dependent manner in LX-2 human hepatic stellate cells, indicating that compounds 1 and 5 should be potential anti-fibrosis agents. These findings give a new insight into the chemical constituents of the polar fraction of olibanum and their inhibitory activities on the TGF- β /Smad signaling pathway.

Fake news impacts individuals' behavior and decision-making while also disrupting political processes, perceptions of medical advice, and societal trends. Improving individuals' ability to accurately assess fake news can reduce its harmful effects. However, previous research on media literacy interventions designed for improving fake news credibility assessments has yielded inconsistent results. We systematically collected 33 independent studies and performed a meta-analysis to examine the effects of media literacy interventions on assessing fake news credibility ( n  = 36,256). The results showed that media literacy interventions significantly improved fake news credibility assessments (Hedges' g  = 0.53, 95% confidence interval [0.29-0.78], p  < 0.001). Gaming interventions were the most effective intervention form. Conversely, the intervention channel, outcome measurement, and subject characteristics (age, gender, and country development level) did not influence the intervention effects.

Objectives: To investigate the level of neuropsychological development in large for gestational age (LGA) infants at the age of 12 months., Methods: The infants, aged 12 to <13 months, who attended the Outpatient Service of Child Care in the First Affiliated Hospital of Shandong First Medical University from December 2021 to June 2023, were enrolled as subjects. According to the gestational age and birth weight, they were divided into preterm appropriate for gestational age (AGA) group, preterm LGA group, early term AGA group, early term LGA group, full-term AGA group, and full-term LGA group. A modified Poisson regression analysis was used to investigate the association between LGA and neuropsychological development outcome at 12 months of age., Results: After adjustment for confounding factors, compared with the full-term AGA group at the age of 12 months, the full-term LGA group had a significant increase in the risk of language deficit ( RR =1.364, 95% CI : 1.063-1.750), the early term LGA group had significant increases in the risk of abnormal gross motor, fine motor, language, and the preterm LGA group had significant increases in the risk of abnormal language, social behavior, and total developmental quotient ( P< 0.05); also, the early term AGA group had higher risks of developmental delay across all five attributes and in total developmental quotient at the age of 12 months ( P< 0.05); except for the language attribute, the preterm AGA group had higher risks of developmental delay in the other 4 attributes ( P< 0.05)., Conclusions: The neuropsychological development of LGA infants with different gestational ages lags behind that of full-term AGA infants at 12 months of age, and follow-up and early intervention of such infants should be taken seriously in clinical practice.

Wavefront coding (WFC) is an effective technique for extending the depth-of-field of imaging systems, including optical encoding and digital decoding. We applied physical prior information and frequency domain model to the wavefront decoding, proposing a reconstruction method by a generative model. Specifically, we rebuild the baseline inspired by the transformer and propose three modules, including the point spread function (PSF) attention layer, multi-feature fusion block, and frequency domain self-attention block. These models are used for end-to-end learning to extract PSF feature information, fuse it into the image features, and further re-normalize the image feature information, respectively. To verify the validity, in the encoding part, we use the genetic algorithm to design a phase mask in a large field-of-view fluorescence microscope system to generate the encoded images. And the experimental results after wavefront decoding show that our method effectively reduces noise, artifacts, and blur. Therefore, we provide a deep-learning wavefront decoding model, which improves reconstruction image quality while considering the large depth-of-field (DOF) of a large field-of-view system, with good potential in detecting digital polymerase chain reaction (dPCR) and biological images.

Five undescribed sesquiterpenoid dimers, aucklandiolides A-E (1-5), one new sesquiterpenoid glycoside, β-cyclocostunolide-15-β-D-glucopyranoside (6), and seventeen known analogues (7-23) were isolated from the roots of Aucklandia costus. Their structures were elucidated by comprehensive HRESIMS and NMR spectroscopic data analysis, and their configurations were confirmed by the computational calculations of ECD and NMR chemical shifts. Aucklandiolides A and B are the first examples of dimeric sesquiterpenoids with a unique 6/6/6/5/6/6 ring system originated from a proposed Diels-Alder cycloaddition between two eudesmane sesquiterpenoids. Besides, compounds 9-11, 20, and 22 showed significant inhibition of nitric oxide production in LPS-stimulated RAW 264.7 cells at a concentration of 20 μM., Competing Interests: Declaration of Competing Interest The authors declare that there are no conflicts of interest., (Copyright © 2023 Elsevier B.V. All rights reserved.)

Candida albicans ( C. albicans ) is an opportunistic pathogenic fungus that often causes mucosal and systemic infections. Several pattern recognition receptors (PRRs), such as Toll-like receptors (TLRs) and C-type lectin receptors (CLRs), have been implicated in the host recognition of C. albicans . These PRRs recognize the pathogen-associated molecular patterns (PAMPs) of C. albicans to activate innate immune cells, thereby rapidly inducing various inflammatory responses by activating intracellular signaling cascades. Herbal medicine and its active components deserve priority development due to their low toxicity and high antibacterial, antiviral and antifungal activities. This review discussed the activities of herbal compounds against C. albicans and their related mechanisms, especially their regulatory role on innate immune cells such as neutrophils, macrophages, and dendritic cells (DCs) implicated in C. albicans infections. Our work aims to find new therapeutic drugs and targets to prevent and treat diseases caused by C. albicans infection with the mechanisms by which this fungus interacts with the innate immune response., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2023 Bao, Li, Bu, Yang, Song, Wang, Wang and Li.)

In Brief: Intrauterine adhesion (IUA) is one of the main causes of female infertility. This study reveals that endoplasmic reticulum stress activation upregulates the TGF-β/SMAD pathway to induce epithelial-mesenchymal transition and promote endometrial fibrosis in an IUA model., Abstract: IUA is a common gynecological disease and is a leading cause of female infertility. Mechanical or infectious damage to the endometrial basal layer can lead to endometrial fibrosis, which is the most common cause of IUA. Endoplasmic reticulum stress (ERS), the transforming growth factor beta signaling pathway (TGF-β/SMAD) and epithelial-mesenchymal transition (EMT) are important factors promoting endometrial fibrosis. The purpose of this study was to determine the up- and downstream regulatory relationships of the above three in the process of endometrial fibrosis. The rat IUA model was induced by double injury method and prophylactic injection of the ERS inhibitor 4-phenylbutyric acid (4-PBA) was given in vivo. The ERS activator tunicamycin and the TGF-β/SMAD pathway inhibitor A 83-01 were used in human endometrial epithelial cells (HEECs) in vitro. Masson's trichrome, Sirius red staining, immunohistochemistry, immunofluorescence and Western blot analyses were used to determine ERS, TGF-β/SMAD pathway, EMT and fibrosis markers in the uterine tissue and HEECs of the different treatment groups. In animal experiments, ERS and the TGF-β/SMAD pathway had been activated and EMT occurred in an in vivo model of IUA but was suppressed in animals treated with prophylactic 4-PBA. In in vitro experiments, tunicamycin-treated HEECs had increased the activation of ERS, the abundance of TGF-β/SMAD pathway and fibrosis markers while EMT occurred, but the TGF-β/SMAD pathway and EMT were significantly inhibited in the tunicamycin+A 83-01 group. Our data suggest that increased ERS can induce EMT and promote endometrial fibrosis through the TGF-β/SMAD pathway.

Natural products derived from natural resources, including nutritional functional food, play an important role in human health. In recent years, the study of anti-fungal and other properties of agri-foods and derived functional compounds has been a hot research topic. Candida albicans is a parasitic fungus that thrives on human mucosal surfaces, which are colonized through opportunistic infection. It is the most prevalent cause of invasive fungal infection in immunocompromised individuals, resulting in a wide variety of clinical symptoms. Moreover, the efficacy of classical therapeutic medications such as fluconazole is often limited by the development of resistance. There is an ongoing need for the development of novel and effective antifungal therapy and medications. Infection of C. albicans is influenced by a great quantity of virulence factors, like adhesion, invasion-promoting enzymes, mycelial growth, and phenotypic change, and among others. Furthermore, various natural products especially from food sources that target C. albicans virulence factors have been researched, providing promising prospects for C. albicans prevention and treatment. In this review, we discuss the virulence factors of C. albicans and how functional foods and derived functional compounds affect them. Our hope is that this review will stimulate additional thoughts and suggestions regarding nutritional functional food and therapeutic development for patients afflicted with C. albicans .

Carbonaceous aerosol is an important component of atmospheric fine particles that has an important impact on air quality, human health, and climate change. In order to explore the long-term changes in carbonaceous aerosol under the background of emission reduction, this study measured the mass concentrations of organic carbon (OC) and elemental carbon (EC) of PM 2.5 , which collected in the northern suburbs of Nanjing for five years (December 17, 2014 to January 5, 2020). The results showed that the five-year average ρ (OC) and ρ (EC) were (10.2±5.3) μg·m -3 and (1.6±1.1) μg·m -3 , accounting for 31.1% and 5.2% of PM 2.5 , respectively. OC and EC concentrations were both high in winter and low in summer. According to the nonparametric Mann-Kendall test and Sen's slope, the mass concentrations of OC and PM 2.5 decreased significantly[OC: P <0.0001, -0.79 μg·(m 3 ·a) -1 , -0.29%·a -1 ; PM 2.5 : P <0.0001, -4.59 μg·(m 3 ·a) -1 , -1.58%·a -1 ]. Although EC had an upward trend, the significance and range of change were not obvious[ P =0.02, 0.05 μg·(m 3 ·a) -1 , 0.02%·a -1 ]. OC and EC decreased significantly during winter from 2014 to 2019[OC: P <0.0001, -2.05 μg·(m 3 ·a) -1 , -0.74%·a -1 ; EC: P =0.001, -0.15 μg·(m 3 ·a) -1 , -0.05%·a -1 ], and the decline was more obvious than the whole. The correlation between OC and EC showed that the sources in winter and summer were more complex than those in spring and autumn. According to the characteristic ratio of OC and EC, the contribution of coal combustion and biomass burning decreased from 2015 to 2019, whereas the impact of industrial sources and vehicle emissions became more significant. Corresponding to this was the obvious decline in OC and the slight recovery of EC. The OC/EC ratio was over 2.0, indicating that there was secondary pollution in the study area. Further calculation revealed that the variation in SOC was consistent with that in OC, showing a significant decrease[ P <0.0001, -0.47 μg·(m 3 ·a) -1 , -0.17%·a -1 ]. The average mass concentration of SOC was (5.0±3.5) μg·m -3 , accounting for 49.2% of OC. These changes indicate clear effects of the prevention and control of air pollution in Nanjing in recent years. Furthermore, future control can focus on the emissions of VOCs to reduce secondary pollution.

Background: In mammals, body mass lost during food restriction is often rapidly regained, and fat is accumulated when ad libitum feeding is resumed. Studies in small cold-acclimated mammals have demonstrated significant mobilization of fat deposits during cold exposure to meet the energy requirements of metabolic thermogenesis. However, no studies to our knowledge have examined the effect of cold exposure on fat accumulation during body mass recovery when refed ad libitum. In this study, striped hamsters restricted to 80% of their regular food intake were then refed ad libitum and exposed to one of three conditions: Intermittent cold temperature (5 °C) for 2 h per day (ICE-2 h/d), intermittent cold temperature (5 °C) for 12 h per day (ICE-12 h/d), or persistent cold exposure (PCE) for four weeks. We measured energy intake, fat deposit mass, serum thyroid hormone levels, and uncoupling protein 1 expression in brown adipose tissue., Results: There was no significant effect of intermittent or persistent cold exposure on body mass regain, whereas energy intake increased significantly and total fat deposit decreased in the ICE-12 h/d and PCE groups compared to the ICE-2 h/d group and control group maintained at 23 °C (CON). In the ICE-12 h/d and PCE groups, hamsters had 39.6 and 38.3% higher serum 3,3',5-triiodothyronine levels, respectively, and 81.6 and 71.3% up-regulated expression of uncoupling protein 1, respectively, in brown adipose tissue compared to their counterparts in the CON group. The rate of mitochondrial state III and state IV respiration O 2 consumption and the activity of cytochrome c oxidase in BAT and liver were significantly higher in the ICE-12 h/d and PCE groups than in the ICE-2 h/d and CON groups., Conclusions: Our findings suggest thyroid hormone-mediated heat production in brown adipose tissue and liver may be involved in preventing fat accumulation during refeeding in animals frequently or persistently exposed to cold conditions., (© 2022. The Author(s).)

Background: Intrauterine adhesion (IUA) is one of the leading causes of infertility and the main clinical challenge is the high recurrence rate. The key to solving this dilemma lies in elucidating the mechanisms of endometrial fibrosis. The aim of our team is to study the mechanism underlying intrauterine adhesion fibrosis and the origin of fibroblasts in the repair of endometrial fibrosis., Methods: Our experimental study involving an animal model of intrauterine adhesion and detection of fibrosis-related molecules. The levels of molecular factors related to the endothelial-to-mesenchymal transition (EndMT) were examined in a rat model of intrauterine adhesion using immunofluorescence, immunohistochemistry, qPCR and Western blot analyses. Main outcome measures are levels of the endothelial marker CD31 and the mesenchymal markers alpha-smooth muscle actin (α-SMA) and vimentin., Results: Immunofluorescence co-localization of CD31 and a-SMA showed that 14 days after moulding, double positive cells for CD31 and a-SMA could be clearly observed in the endometrium. Decreased CD31 levels and increased α-SMA and vimentin levels indicate that EndMT is involved in intrauterine adhesion fibrosis., Conclusions: Endothelial cells promote the emergence of fibroblasts via the EndMT during the endometrial fibrosis of intrauterine adhesions., (© 2022. The Author(s).)

Influenza A virus (IAV) is internalized into its host cells by endocytosis, which involves many cellular proteins and molecules. In this study, we focus on the function of calcium ion (Ca 2+ ) in IAV endocytosis. We have found that IAV infection is accompanied by the increase in concentration of cytosolic Ca 2+ , which is mainly attributed to the influx of extracellular Ca 2+ . When Ca 2+ influx is abolished, IAV internalization will be markedly suppressed, but the virus attachment to its host cells will be unaffected. Extracellular Ca 2+ influx is essential to the clathrin-mediated endocytosis (CME) of IAVs but dispensable to the clathrin-independent endocytosis of the virus and is dispensable to the CME of transferrin or low-density lipoprotein as a control. Ca 2+ influx might participate in the dynamin-promoted membrane fission in the CME of IAVs. Our study highlights that IAVs enter host cells via extracellular Ca 2+ influx-involved clathrin- and dynamin-dependent endocytosis, which will facilitate better understanding of IAV infection and development of anti-influenza drugs.

Black carbon (BC) is an important component of atmospheric particulate matter (PM) emitted during the combustion process. Light absorption and scattering exhibited by BC affect the exchange of solar energy on Earth. In this study, continuous measurements of atmospheric particulate BC were carried out, using a BC analyzer (AE33) in the suburban area of Nanjing from January 2019 to May 2019, to realize the diurnal variations of BC during the different seasons and potential sources of BC during the clean (CD, PM 2.5 <35 μg ·m -3 ) and haze days (PD, PM 2.5 >75 μg ·m -3 ). The results showed that the average concentration of BC was (3.8±2.3) μg ·m -3 ; a higher average BC concentration value of (4.3±2.6) μg ·m -3 was observed during the winter, exceeding that during the spring period by a factor of 1.3. The higher BC concentrations during the winter was attributed to the stagnant weather conditions and additional emissions. Significant diurnal cycles of BC were observed with higher BC concentrations during rush hours of traffic, suggesting traffic origins. The Ångström exponent were 1.32 and 1.30 during the spring and winter periods, respectively, indicating that the BC was mainly produced from the traffic emissions during both the seasons. This hypothesis was also supported by the average BC/CO ratio of 0.005, which was similar to that of BC derived by traffic emissions. Moreover, we discovered that the contributions of traffic emissions to BC were 68%-87% and 72%-86% during the haze and clean periods, respectively. This indicated enhanced contributions of coal combustion and biomass burning to BC in Nanjing during the haze events. Finally, using the potential source contribution function (PSCF) and concentration weighted trajectory (CWT) analysis, we highlighted that the BC at the receptor site was mainly from the local emissions in the surrounding areas of Nanjing.

In this study, PM 2.5 samples were collected from October to November of 2015 in the northern suburb of Nanjing. The mass concentrations of organic carbon (OC), elemental carbon (EC), and levoglucosan in the samples were analyzed by thermal optical transmittance (TOT) and ion chromatography. The average concentrations of OC and EC were respectively (11.3±4.9) μg·m -3 and (1.1±0.9) μg·m -3 . The average total carbon (TC) was 22.9%, and the OC/EC was 7.4. The quality concentrations of PM 2.5 , OC, EC, and SOC all reflected daytime features, and the correlation between OC and EC was better during the day than at night (correlation coefficients of 0.86 for day and 0.7 for night). By analyzing the mass concentrations of PM 2.5 , levoglucosan, and SOC, as well as the data of backward trajectories and fire point data, it was determined that the northern suburb of Nanjing is affected by the long-distance transportation of biomass from Hebei and other places from October 13-16. The correlations between levoglucosan and OC, EC, or SOC were significant (correlation coefficients of 0.78, 0.79, and 0.65, respectively), and the contribution of biomass combustion during sampling to OC was 21.9%.

A total of 32 daily PM 2.5 samples were collected from December 2016 to February 2017 in the urban area of Xuzhou city. Water-soluble inorganic ions (WSⅡs), including F - , Cl - , NO 3 - , SO 4 2- , Na + , Mg 2+ , NH 4 + , K + and Ca 2+ , were determined by ion chromatography. The average mass concentration of PM 2.5 was (164.8±77.3) μg·m -3 and the average total mass concentration of the nine ions was (67.5±36.1) μg·m -3 , the contribution of the WSⅡs to the PM 2.5 was more than 40.9%. The order of the concentrations of individual ions was NO 3 - > SO 4 2- > NH 4 + > Cl - > Ca 2+ > K + > Na + > Mg 2+ > F - . NH 4 + , NO 3 - , and SO 4 2- (SNA) were the major components of the water-soluble ions in the PM 2.5 measurement. The average mass concentration of WSⅡs in clean air, mild haze, and severe haze was (12.8±8.8), (59.0±22.8) and (86.3±36.0) μg·m -3 , respectively. The contribution of SNA to WSⅡs was 86.4%, 82.8%, and 78.9%, respectively. The correlation between each component of SNA with each other was significant. NH 4 + , NO 3 - , and SO 4 2- were in the form of (NH 4 ) 2 SO 4 and NH 4 NO 3 . Secondary formation, biomass burning, fossil fuel combustion, and dust were the major sources of the water-soluble ions in PM 2.5 .

Objective: To investigate the cause and related risk factors of an outbreak caused by Brucellosis., Methods: Epidemiological investigation and laboratory test were carried out among occupationally invloved population including sheep slaughters and sellers in the village., Results: 18 people were serology positive among the 129 occupationally involved persons under survey. Seven of them were confirmed cases, 11 were latent infection, to make the overall attack rate as 14%. 90% of the sheep were from high-risk areas of Brucella. Among the occupationally involved persons, 89% of them never wore face masks, 84% never wear overalls and 70% never wear gloves. Factors as:work but wearing no gloves (RR = 7.4, 95%CI:1.1-53.0), with hand wound (RR = 3.4, 95%CI:1.1-11.0) could increase the risk of Brucella infection., Conclusion: The cause of this outbreak was due to the plentiful influx of unchecked sheep from the northern part of China and the employees in the process of sheep slaughtering or trading were lack of effective prevention programs.