363 research outputs found

    A 10-MM_{\odot} YSO with a Keplerian disk and a nonthermal radio jet

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    We previously observed the star-forming region G16.59-0.05 through interferometric observations of both thermal and maser lines, and identified a high-mass young stellar object (YSO) which is surrounded by an accretion disk and drives a nonthermal radio jet. We performed high-angular-resolution (beam FWHM ~0.15") 1.2-mm continuum and line observations towards G16.59-0.05 with the Atacama Large Millimeter Array (ALMA). The main dust clump, with size ~104^4 au, is resolved into four relatively compact (diameter ~2000 au) millimeter (mm) sources. The source harboring the high-mass YSO is the most prominent in molecular emission. By fitting the emission profiles of several unblended and optically thin transitions of CH3_3OCH3_3 and CH3_3OH, we derived gas temperatures inside the mm-sources in the range 42--131 K, and calculated masses of 1--5 MM_{\odot}. A well-defined Local Standard of Rest velocity (Vlsr) gradient is detected in most of the high-density molecular tracers at the position of the high-mass YSO, pinpointed by compact 22-GHz free-free emission. This gradient is oriented along a direction forming a large (~70 degree) angle with the radio jet, traced by elongated 13-GHz continuum emission. The butterfly-like shapes of the P-V plots and the linear pattern of the emission peaks of the molecular lines at high velocity confirm that this Vlsr gradient is due to rotation of the gas in the disk surrounding the high-mass YSO. The disk radius is ~500 au, and the Vlsr distribution along the major axis of the disk is well reproduced by a Keplerian profile around a central mass of 10±\pm2 MM_{\odot}. The position of the YSO is offset by >~ 0.1" from the axis of the radio jet and the dust emission peak. To explain this displacement we argue that the high-mass YSO could have moved from the center of the parental mm source owing to dynamical interaction with one or more companions.Comment: 16 pages, 12 figures, accepted by Astronomy & Astrophysics, Main Journa

    DIVERSITY AND HABITAT PROFILE OF THE SHALLOW WATER HOLOTHURIANS IN CAMOTES ISLANDS, CENTRAL PHILIPPINES

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    Species diversity and habitat profile of holothurians in Camotes Islands, Cebu Philippines were studied as baseline data for resource and ecological management. A 150 meter transect was laid in sandy, muddy and rocky substrates of the coastal barangays during the day and night assessments of the four municipalities of Camotes Islands which are San Francisco, Poro, Tudela and Pilar. Physico-chemical instruments and interview guide to the gleaners were used to gather data. Actual collection of specimen and other data was done in every 10 meter distance in the transect where a 1m quadrat was used. Results show that there are 20 species of holothurians belonging to 3 families namely Holothuriidae, Stichopodidae and Synaptidae. There are 2 species found in sandy substrate; 10 in muddy substrate; 2 in pure rocky substrate and 6 found in both rocky and muddy substrates. Results further show that there are 13 common species of Holothurians found in the four municipalities. The most diverse municipality is San Francisco which has 18 species followed by Poro (15); Pilar (14) and Tudela (13). For the distinct species, Holothuria rigida is found only in San Francisco followed by Pearsonothuria graffei (in Tudela and Pilar); Physico-chemical parameters like salinity, range from 23-38 ppt; temperature is 260C-350C, pH 4.5-8.0 both day and night assessments. Substrate grain size analysis shows that 100 microns dominate the amount of substrates in all the barangays, followed by 200 microns and then 400 microns. Keywords: Diversity, Habitat Profile, Holothurians, Camotes Island

    Avaliação da degradação de hidrocarbonetos policíclicos aromáticos (HPA) em solos arenosos utilizando como oxidante persulfato de sódio ativado com Ferro.

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    Polycyclic Aromatic Hydrocarbons (PAHs) are pollutants that can cause mutagenic and carcinogenic to humans and cause environmental harm. The present study evaluated the degradation of phenanthrene and anthracene contaminants present in sandy soils using sodium persulfate activated with Fe2+ in acid medium. It was evaluated three sandy soils named A, B and C with different organic carbon tenors of 27, 16 and 31 g kg-1 respectively. After 24 hours of reaction, it was achieved a treatment efficiency of 60, 45 and 11% for the phenanthrene and 97, 96 and 81% for anthracene. There was no change in the composition of organic carbon in soil after the use of the oxidant. However there was a change in the constitution of the soil humic fractions. The use of the persulfate oxidant may be considered promising for use in soil because it does not compete with the organic carbon in the soil

    Research on Experiential Marketing from the Qingdao International Beer Festival

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    近年来,“体验”一词成为营销界出现频率越来越高的词汇。在学术界,早在上世纪70年代就有学者提出,但较为集中和富有成果的研究基本都在2000以后才出现,并且长期以来都以约瑟夫·派恩、詹姆斯·吉尔摩和伯德·施密特博士的研究为奠基之作;在业界,体验营销作为一种新型的营销方式,在国外的很多企业,尤其是很多跨国企业中已经得到了很成熟的应用,并且取得了很好的效果,而在国内,由于多种原因,只在小部分企业当中得以应用,普及程度并不高。不管未来如何,现如今体验式营销作为一种为消费者带来个性化消费体验的营销手段,已经逐渐开始流行并被商家所接受和采用,研究体验营销及其应用,对国内产品品牌建设方面有很高的借鉴价值。 ...In recent years, the word “experiencing” appears more and more frequently in the marketing area. As a matter of fact,the concept of experiential marketing had been mentioned during the 1970s. As a new way of marketing, experiential marketing has already been widely used in foreign enterprises, especially in the transnational enterprises. Howerer, in china, as a result of several things, experienti...学位:文学硕士院系专业:新闻传播学院广告学系_传播学学号:1052006115025

    CD4+CD25+ Regulatory T Cells Can Mediate Suppressor Function in the Absence of Transforming Growth Factor β1 Production and Responsiveness

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    CD4+CD25+ regulatory T cells inhibit organ-specific autoimmune diseases induced by CD4+CD25−T cells and are potent suppressors of T cell activation in vitro. Their mechanism of suppression remains unknown, but most in vitro studies suggest that it is cell contact–dependent and cytokine independent. The role of TGF-β1 in CD4+CD25+ suppressor function remains unclear. While most studies have failed to reverse suppression with anti–transforming growth factor (TGF)-β1 in vitro, one recent study has reported that CD4+CD25+ T cells express cell surface TGF-β1 and that suppression can be completely abrogated by high concentrations of anti–TGF-β suggesting that cell-associated TGF-β1 was the primary effector of CD4+CD25+-mediated suppression. Here, we have reevaluated the role of TGF-β1 in CD4+CD25+-mediated suppression. Neutralization of TGF-β1 with either monoclonal antibody (mAb) or soluble TGF-βRII-Fc did not reverse in vitro suppression mediated by resting or activated CD4+CD25+ T cells. Responder T cells from Smad3−/− or dominant-negative TGF-β type RII transgenic (DNRIITg) mice, that are both unresponsive to TGF-β1–induced growth arrest, were as susceptible to CD4+CD25+-mediated suppression as T cells from wild-type mice. Furthermore, CD4+CD25+ T cells from neonatal TGF-β1−/− mice were as suppressive as CD4+CD25+ from TGF-β1+/+ mice. Collectively, these results demonstrate that CD4+CD25+ suppressor function can occur independently of TGF-β1

    Lung retrieval from non–heart beating cadavers with the use of a rat lung transplant model

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    AbstractBackground: Lungs retrieved from cadavers after death and circulatory arrest may alleviate the critical shortage of lungs for transplant. We report a rat lung transplantation model that allows serial measurement of arterial blood gases after left single lung transplantation from non–heart beating donors. Methods: Twelve Sprague-Dawley rats underwent left lung transplantation with a vascular cuff technique. Donor rats were anesthetized with intraperitoneal injection of pentobarbital, heparinized, intubated via tracheotomy, and then killed with pentobarbital. Lungs were retrieved immediately or after 2 hours of oxygen ventilation after death (tidal volume 1 mL/100 g, rate 40/min FIO2 = 1.0, positive end-expiratory pressure 5 cm H2O). Recipient rats were anesthetized, intubated, and ventilated. The carotid artery and jugular vein were cannulated for arterial blood gases and infusion of Ringer's lactate (4 mL/h). Anesthesia was maintained with halothane 0.2%, and recipient arterial blood gases were measured at 4 and 6 hours after lung transplantation after snaring the right pulmonary artery for 5 minutes. Animals were put to death 6 hours after lung transplantation, and portions of transplanted lungs were frozen in liquid nitrogen and assayed for wet/dry ratio, myeloperoxidase as a measure of neutrophil infiltration, and conjugated dienes as a measure of free radical–mediated lipid peroxidation. Results: Arterial PO2 and wet/dry ratio were not significantly different in recipients of non–heart beating donor lungs retrieved immediately after death or after 2 hours of oxygen ventilation. Significant neutrophil infiltration was observed in recipients of non–heart beating donor lungs retrieved 2 hours after death from oxygenventilated donors. Conclusions: Strategies to ameliorate reperfusion injury may allow for successful lung transplantation from non–heart beating donors.J Thorac Cardiovasc Surg 2001;122:18-2

    Trimethoxylated halogenated chalcones as dual inhibitors of mao-b and bace-1 for the treatment of neurodegenerative disorders

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    Six halogenated trimethoxy chalcone derivatives (CH1–CH6) were synthesized and spec-trally characterized. The compounds were further evaluated for their inhibitory potential against monoamine oxidases (MAOs) and β-secretase (BACE-1). Six compounds inhibited MAO-B more effectively than MAO-A, and the 2′,3′,4′-methoxy moiety in CH4–CH6 was more effective for MAO-B inhibition than the 2′,4′,6′-methoxy moiety in CH1–CH3. Compound CH5 most potently inhibited MAO-B, with an IC50 value of 0.46 µM, followed by CH4 (IC50 = 0.84 µM). In 2′,3′,4′-methoxy derivatives (CH4-CH6), the order of inhibition was –Br in CH5 >-Cl in CH4 >-F in CH6 at the para-position in ring B of chalcone. CH4 and CH5 were selective for MAO-B, with selectivity index (SI) values of 15.1 and 31.3, respectively, over MAO-A. CH4 and CH5 moderately inhibited BACE-1 with IC50 values of 13.6 and 19.8 µM, respectively. When CH4 and CH5 were assessed for their cell viability studies on the normal African Green Monkey kidney cell line (VERO) using MTT assays, it was noted that both compounds were found to be safe, and only a slightly toxic effect was observed in concentrations above 200 µg/mL. CH4 and CH5 decreased reactive oxygen species (ROS) levels of VERO cells treated with H2 O2, indicating both compounds retained protective effects on the cells by antioxidant activities. All compounds showed high blood brain barrier permeabilities analyzed by a parallel artificial membrane permeability assay (PAMPA). Molecular docking and ADME prediction of the lead compounds provided more insights into the rationale behind the binding and the CNS drug likeness. From non-test mutagenicity and cardiotoxicity studies, CH4 and CH5 were non-mutagenic and non-/weak-cardiotoxic. These results suggest that CH4 and CH5 could be considered candidates for the cure of neurological dysfunctions
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