Existing forms of REE in gold-bearing pyrite of the Jinshan gold deposit,Jiangxi Province,China

Rare earth element(REE) is widely used in various fields of geology.Study of the existing forms of REE in geological objects is a necessity for us to solve geological problems related with REE.This paper tried to make it clear the existing forms of REE in gold-bearing pyrite in Jinshan gold deposit by stepwise dissolution test with ICP-MS analysis.Results showed that content of REE in fluid-inclusions of gold-bearing pyrite was very low,which only took about 0.07%–0.70% of the ΣREE,and that of pyrite phase ...

Inventory of mangrove wetlands in the Pearl River Estuary of China using remote sensing

Mangrove forests have important ecological functions in protecting the environment. However, the mangrove wetlands have been largely lost because of intensified human activities in the study area. Remote sensing can be conveniently used for the inventory of mangrove forests because field investigation is very difficult. In this study, a knowledge-based system is developed to retrieve spatio-temporal dynamics of mangrove wetlands using multi-temporal remote sensing data. Radar remote sensing data are also used to provide complementary information for the quantitative analysis of mangrove wetlands. Radar remote sensing is able to penetrate mangrove forests and obtain the trunk information about mangrove structures. The integration of radar remote sensing with optical remote sensing can significantly improve the accuracies of classifying mangrove wetland types and estimating wetland biomass.

The effect of renal artery stenting on hypertension and renal function in patients with atherosclerotic renovascular disease

Background The purpose of this study was to evaluate the effects of percutaneous transluminal renalr stenting (PTRS) on hypertension and renal function in patients with atherosclerotic renovascular disease.Methods A total of 147 stents were deployed in 147 lesions of 135 consecutive patients for poorly controlled hypertension or preservation of renal function. Clinical follow-up of the effect of the procedure on renal function, blood pressure control, number of antihypertensive medications, and survival was performed in 128 (95%) patients after 22±14 months. Angiographic follow-up were performed in 70% of the patients at 7.24-5.6 months after PTRS. Results The immediate technical success was 100%. At 22±14 months, systolic and diastolic blood pressures significantly decreased (from 172±23 to 159±20 mm Hg and from 93±16 to 85±13 mm Hg, respectively; P<0.05). The number of antihypertensive medications was reduced on average by 0.74 (from 2.6±1.8 to 1.9±1.7, P<0.01). Among the 49 patients whose renal function was impaired initially (Serum creatinine concentration (SCC) >130 μmol/L), SCC was improved in 25%, became stabilized in 48% and continued to deteriorate in 27%. When SCC was <130 μtmol/L, 97% of the patients remained stabilized, while only 2 patients, SCC deteriorated by 22 months. The cumulative probability of survival was 96% (129/135) at 22 months, with 3 deaths related to end-stage renal disease. The in-stentrestenosis rate was 7.4% (7/95) at a mean follow up of 7.2±5.6 months.Conclusions In patients with atherosclerotic renal-artery stenosis, PTRS could beneficially affect blood pressure control and may improve or prevent further deterioration of renal function.

Protective effects of curcumin against human immunodeficiency virus 1 gp120 V3 loop-induced neuronal injury in rats

Curcumin improves the learning and memory deficits in rats induced by the gp120 V3 loop. The present study cultured rat hippocampal neurons with 1 nM gp120 V3 loop and 1 μM curcumin for 24 hours. The results showed that curcumin inhibited the gp120 V3 loop-induced mitochondrial membrane potential decrease, reduced the mRNA expression of the pro-apoptotic gene caspase-3, and attenuated hippocampal neuronal injury.

Establishment and characterization of a new cell line derived from human colorectal laterally spreading tumor

AIM:To study the molecular mechanism of laterally spreading tumor (LST), a cell line [Laterally Spreading Tumor-Rectum 1 (LST-R1)] was derived and the characteristics of this cell line were investigated. METHODS:A new cell line (LST-R1) originated from laterally spreading tumor was established. Properties of the cell line were characterized using scanning and transmission electron microscopy, immunohistochemistry method, cytogenetic analysis and nude mice xenograft experiments. In vitro invasion assay, cDNA microarray and Western blotting were used to compare the difference between the LST-R1 and other colorectal cancer cell lines derived from prudent colon cancer. RESULTS:Our study demonstrated that both epithelial special antigen (ESA) and cytokeratin-20 (CK20) were expressed in LST-R1. The cells presented microvilli and tight junction with large nuclei. The karyotypic analysis showed hyperdiploid features with structural chromosome aberrations. The in vivo tumorigenicity was also demonstrated in nude mice xenograft experiments. The invasion assay suggested this cell line has a higher invasive ability. cDNA microarray and Western blotting show the loss of the expression of E-cadherin in LST-R1 cells.CONCLUSION:We established and characterized a colorectal cancer cell line, LST-R1 and LST-R1 has an obvious malignant tendency, which maybe partially attributed to the changes of the expression of some adhesion molecules, such as E-cadherin. It is also a versatile tool for exploring the original and progressive mechanisms of laterally spreading tumor and the early colon cancer genesis.

House dust mite allergen Der f enhanced bronchial epithelial cell cytokine expression

The house dust mites (Dermatophagoides farinae, Derf) are the major source of aeroaller gens implicated in the expression of atopic disorders, including asthma, allergic rhinitis and atopic dermatitis. In particular, strong circumstantial evidence suggests that house dust mite antigens are important precipitating factors of asthma. Many house dust mite allergens are proteases that can elicit airway inflammation by stimulating the release of cytokines from bronchial epithelial cells. To investigate whether Der f allergen proteases induced cytokine production from the epithelial cell line BEAS-2B, BEAS-2B cells were cultured with 4 different concentrations of Derf (0.02, 0.2, 2, 20μg/ml) for 24-96 h, after which supernatants were assayed for interleukin (IL)-6 and IL-8 with ELISA. Reverse transcription-PCR was also performed. The cell sheets were intact throughout the observation in control group without any exposure to Der f antigen. In the experimental groups cells treated with Der f allergen showed changes in the anchorage status of the monolayer. There was a significant increase in the level of cytokine production compared with the untreated sample. The release of IL-6 and IL-8 increased in a concentration-dependent manner (P <0.05, respectively) with the addition of increasing dosage of Der f to the cell sheets. Levels of IL-6 and IL-8 began to rise at 24 h and 48 h after allergen exposure, and they increased significantly in the supematants at 72 h and 96 h. At the same time the concentration dependence of induction of IL-6 and IL-8 expression as well as an increase in the expression of IL-6 and IL-8 mRNA manifested evidently. HDM-induced airway inflammation may include Der f-mediated release of inflammatory mediators, and the proteolytic activity of an allergen may stimulate the release of proinflammatory cytokines from human bronchial epithelium. It is suggested that IL-6 and IL-8 production by bronchial epithelial cells may play a role in the pathogenesis of allergic asthma.

Photoluminescent Properties and Applications of Platinum(Ⅱ)Complexes Molecularly Dispersed in Polymer Matrices

The photoluminescence of some platinum(Ⅱ)complexes of aromaticα-diimines and pyridine-2-thiolates is enhanced upon incorporation into the polymer matrices polymethmethylacrylate(PMMA),polycarbonate,and polystyrene.Some applications of the platinum(Ⅱ)-PMMA films as luminscent sensors reported.When platinum(Ⅱ)-PMMA films are in ethanol solutions with different chloroform concentration,there is a systematic decrease of emission intensity with increasing chloroform concentration and the variation follows a Stern-volmer relationship.

汉字部件及其位置的发展研究

选取小学二年级、五年级学生和大学生对汉字部件及其位置的发展进行了研究。结果表明,汉字部件的发展在3个年级表现出一致的趋势。部件位置的发展趋势不一致,它在小学五年级阶段表现出更重要的作用。

Curcumin protects against interleukin-6-induced rapid Ca～(2+) influx in rat hippocampal neurons

The current study sought to investigate the potential protective action of curcumin against interleukin-6-induced injury in rat hippocampal neurons. The results revealed that interleukin-6 induced typical cellular injury, such as the swelling of cell bodies and increased Ca^2＋ concentration. After administration of curcumin, interleukin-6-induced neurons recovered to a normal state, and the fluorescence intensity of Ca^2＋ gradually returned to normal. These findings suggest that curcumin exerts a protective effect on hippocampal neurons of rats. In addition, our results suggest that the protective effect of curcumin involves prevention of the rapid Ca^2＋ influx induced by interleukin-6, which maintains Ca^2＋ homeostasis.

Effects of humic acid on recoverability and fractal structure of alum-kaolin flocs

Particle surface characteristics, floc recoverability and fractal structure of alum-kaolin flocs were investigated using in situ particle image velocimetry （PIV） and microbalance with or without humic acid. Experimental results indicated that the zeta potential of kaolin particle surface after adsorption of humic acid was related with humic acid concentration and its acid-base buffering capacity. Adsorption of humic acid resulted in more negative electrophoresis on the particle surface. Coagulant dosages for particles to form flocs would increase with increasing humic concentration. PIV was used to evaluate floc structural fragmentation, floc surface erosion as well as recoverability after high shear. It was found that the floc size during the steady phase of growth was small, while the regrowing capability decreased in the presence of humic acid. The recoverability was closely related with floc breakage modes including floc structural fragmentation and floc surface erosion. The fractal dimensions of alum-kaolin flocs by mass-size method based on microbalance would decrease with increasing humic concentration. This study proved that humic acid had adverse influences on the performance of coagulation process.

Value of qualitative research in polycystic ovary syndrome

Objective This article aims to introduce the benefits of qualitative research and to discuss how such research can be applied to the study of polycystic ovary syndrome （PCOS）. Data sources Relevant articles were published in English as of May 2013 from Pubmed. Terms ＂polycystic ovary syndrome/PCOS, qualitative research and methodology＂ were used for searching. Study selection Articles studying PCOS with qualitative methods were reviewed. Articles associated with the use of qualitative research in clinical research were cited. Results Six qualitative studies related to PCOS were found in the literature search. These studies addressed different aspects in PCOS women including their womanhood, lived experience, information need, and experience of treatment with acupuncture. Five of these six studies used phenomenology as guiding theory. Conclusion Quantitative research has been the dominant approach in the field so far, qualitative research is relevant to the advancement of PCOS.

Spectral Analysis for Preconditioning of Multi-Dimensional Riesz Fractional Diffusion Equations

In this paper,we analyze the spectra of the preconditioned matrices arising from discretized multi-dimensional Riesz spatial fractional diffusion equations.The finite difference method is employed to approximate the multi-dimensional Riesz fractional derivatives,which generates symmetric positive definite ill-conditioned multi-level Toeplitz matrices.The preconditioned conjugate gradient method with a preconditioner based on the sine transform is employed to solve the resulting linear system.Theoretically,we prove that the spectra of the preconditioned matrices are uniformly bounded in the open interval(12,32)and thus the preconditioned conjugate gradient method converges linearly within an iteration number independent of the discretization step-size.Moreover,the proposed method can be extended to handle ill-conditioned multi-level Toeplitz matrices whose blocks are generated by functions with zeros of fractional order.Our theoretical results fill in a vacancy in the literature.Numerical examples are presented to show the convergence performance of the proposed preconditioner that is better than other preconditioners.

医用钛表面纳米薄膜的制备及生物相容性研究

本实验采用经抛光打磨的纯钛片与氢氧化钠溶液进行水热反应,在钛片表面形成一维钛酸盐纳米结构薄膜,水热处理后的样品浸泡在模拟体液中进一步矿化,研究其表面诱导磷灰石沉积的能力。采用TEM、SEM、XRD、FTIR和EDX等测试手段表征样品矿化前后钛片表面的微观形貌、结构及元素组成。研究了反应时间对样品表面微观结构及性质的影响,并探讨了纳米结构形成的机理。通过对样品矿化后表面羟基磷灰石形成情况的研究,得出了最佳仿生表面的微观结构组成。结果显示:钛片与氢氧化钠水热反应能在其表面形成结构规整,尺寸均一的纳米结构薄膜;TEM结果表明钛片与6 mol/L氢氧化钠溶液在180℃条件下反应1 h便可观察到纳米结构的形成;通过对比不同反应条件下样品表面纳米结构的SEM结果得知:反应时间对表面薄膜的纳米结构的尺寸及结构均有影响;FTIR及XRD结果表明水热处理后的钛片表面有钛酸盐和钛酸生成,EDX及XRD结果显示水热处理后的钛片经SBF浸泡7 d后其表面能够诱导磷灰石沉积。

TiO_2纳米管/PLGA可降解多孔支架材料的制备

为了增加无机-有机杂化材料的稳定性和均一性,满足其在组织工程领域的实际应用。本文采用接枝法修饰二氧化钛纳米管,随后将其与丙交酯-乙交酯共聚物(PLGA)复合。并利用溶液浇铸/粒子浸出法制备出组织工程用多孔生物支架。采用核磁(1H-NMR)、傅里叶变换红外光谱仪(FTIR)、热重分析(TGA)、扫描电子显微镜(SEM)、透射电子显微镜(TEM)等对杂化支架材料的结构与形貌进行表征;并研究了杂化支架与纯的PLGA支架表面矿化行为以及表面亲水性能。结果表明:TiO2纳米管接枝到PLGA表面,分布较均匀,且平均接枝量为18.8%左右;TiO2纳米管/PLGA杂化支架更有利于钙磷层的沉积以及其表面亲水性能的提高。

Analogous comparison unravels heightened antiviral defense and boosted viral infection upon immunosuppression in bat organoids

Horseshoe bats host numerous SARS-related coronaviruses without overt disease signs.Bat intestinal organoids,a unique model of bat intestinal epithelium,allow direct comparison with human intestinal organoids.We sought to unravel the cellular mechanism(s)underlying bat tolerance of coronaviruses by comparing the innate immunity in bat and human organoids.We optimized the culture medium,which enabled a consecutive passage of bat intestinal organoids for over one year.Basal expression levels of IFNs and IFN-stimulated genes were higher in bat organoids than in their human counterparts.Notably,bat organoids mounted a more rapid,robust and prolonged antiviral defense than human organoids upon Poly(I:C)stimulation.TLR3 and RLR might be the conserved pathways mediating antiviral response in bat and human intestinal organoids.The susceptibility of bat organoids to a bat coronavirus CoV-HKU4,but resistance to EV-71,an enterovirus of exclusive human origin,indicated that bat organoids adequately recapitulated the authentic susceptibility of bats to certain viruses.Importantly,TLR3/RLR inhibition in bat organoids significantly boosted viral growth in the early phase after SARS-CoV-2 or CoV-HKU4 infection.Collectively,the higher basal expression of antiviral genes,especially more rapid and robust induction of innate immune response,empowered bat cells to curtail virus propagation in the early phase of infection.