Search results for "Diss"

Thiolate Adsorption on Au(hkl) and Equilibrium Shape of Large Thiolate-covered Gold Nanoparticles

2013

The adsorption of thiolates on Au surfaces employing density-functional-theory calculations has been studied. The dissociative chemisorption of dimethyl disulfide (CH3S−SCH3) on 14 different Au(hkl) is used as a model system. We discuss trends on adsorption energies, bond lengths, and bond angles as the surface structure changes, considering every possible Au(hkl) with h, k, l ≤ 3 plus the kinked Au(421). Methanethiolate (CH3S-) prefers adsorption on bridge sites on all surfaces considered; hollow and on top sites are highly unfavourable. The interface tensions for Au(hkl)-thiolate interfaces is determined at low coverage. Using the interface tensions in a Wulff construction method, we cons…

Validation of the Tetracycline Regulatable Gene Expression System for the Study of the Pathogenesis of Infectious Disease

2011

Understanding the pathogenesis of infectious disease requires the examination and successful integration of parameters related to both microbial virulence and host responses. As a practical and powerful method to control microbial gene expression, including in vivo, the tetracycline-regulatable system has recently gained the favor of many investigative groups. However, some immunomodulatory effects of the tetracyclines, including doxycycline, could potentially limit its use to evaluate host responses during infection. Here we have used a well-established murine model of disseminated candidiasis, which is highly dependent on both the virulence displayed by the fungal cells and on the host im…

Toll-like receptor 2 is dispensable for acquired host immune resistance to Candida albicans in a murine model of disseminated candidiasis

2004

Previous work by our group showed that Toll-like receptor 2 (TLR2) is essential for activation of innate immunity, playing a major role in the response of macrophages to Candida albicans, triggering cytokine and chemokine expression, and therefore TLR2 -/- mice are more susceptible to systemic primary candidiasis. In this work, we used a murine model of systemic C. albicans infection, in which resistance to reinfection with virulent wild-type cells is induced by prior exposure of mice to a low-virulence agerminative strain of C. albicans (primary sublethal infection), to study the influence of TLR2 gene deletion on (i) the ability to develop an acquired resistance upon vaccination; (ii) the…

Can Tumor Oxygenation be Improved by Reducing Cellular Oxygen Consumption?

1999

Tumor hypoxia, which can be found in many experimental and human tumors is an important factor influencing the therapeutic efficacy of standard radiotherapy, O2-dependent chemotherapy and photodynamic therapy (Hall, 1994) and might be responsible for the development of aggressive tumor cell subpopulations (Graeber et al., 1996). Since this oxygen deficiency results from a disparity between O2 supply to the tumor tissue and the oxygen demand of the cells, several attempts have been undertaken to improve tumor oxygenation primarily by increasing the arterial oxygen supply. The O2 supply to the tumor cells can be improved by (a) increasing the arterial O2 content (by breathing hyperoxic gases …

Type B Aortic Dissection Diagnosed by Left-Sided Transthoracic Ultrasonography in a Woman With Preeclampsia

2017

Scope-Oriented Thermoeconomic analysis of energy systems. Part I: Looking for a non-postulated cost accounting for the dissipative devices of a vapou…

2010

Abstract The authors of the main thermoeconomic methodologies developed in the last two decades have recently focused their efforts on the analysis of dissipative devices, i.e. those components whose productive purpose is neither intuitive nor easy to define. Coherent and unanimously accepted cost structures have been identified for dissipative components, while ambiguities still exist as concerns the cost allocation principles to be adopted. Being this aspect evidently cost-influencing, accurate analyses focused on the subjectivity of results are needed. This paper is structured in two parts. In the Part I an in-depth study of some critical issues arising from the thermoeconomic analysis o…

Organizational dissent and workplace freedom of speech : a qualitative study of young professional intra-urban migrant workers in Shanghai

2014

Chinese economy reform triggered the largest domestic labor migration in human history. These 150 million migrant workers are treated as second-rate citizens in urban cities because of the discriminatory household registration system: Hukou. Previous studies have predominantly focused on blue-collar migrants while the professional workers, the potential permanent city dwellers, received little attention. This study attempts to fill this gap by exploring the perception of workplace freedom and preference of dissent strategy among professional migrant workers in Shanghai. Eight young and well-educated migrants participated in this study through semi-structured online interviews. This study no…

Comparison of thermal stratification, light attenuation and Chlorophyll-a dynamics between the ends of Lake Tanganyika

2002

Thermal structure, light attenuation, and chlorophyll-a dynamics within the upper 100 m at the northern and southern ends of Lake Tanganyika were measured from August 1995–July 1996. Pronounced variability of thermal structure in time, depth and region were observed. During the dry windy season (June–September), the water column in the south was largely isothermal down to 100 m, while in the north stratification was detectable. Subsequently, in October, cessation of winds coincided with a reestablishment and strengthening of thermal stratification in the south, and a distinct rise of a weakened thermocline in the north was accompanied by an increase in epilimnetic concentrations of dissolve…

Spectral attenuation of solar ultraviolet radiation in humic lakes in Central Finland

2003

The attenuation of solar ultraviolet (UV) radiation in five lakes in Central Finland was evaluated through field measurements and/or by determining the optical properties of the lake water during summer 1999. Spectral UV irradiance in the air and at several depths underwater was measured in three lakes (Lake Palosjärvi, Konnevesi, and Jyväsjärvi) with dissolved organic carbon (DOC) ranging from 4.9 to 8.7 mg l(-1) and chlorophyll a ranging from 1.6 to 16 g l(-1). According to the field measurements, 99% of the UV-B radiation was attenuated in approximately a half meter water column in the clearest lake. In the UV-A region at 380 nm, the corresponding attenuation occurred in the upper one me…

Water-Soluble Chlorophyll Protein (WSCP) Stably Binds Two or Four Chlorophylls

2017

Water-soluble chlorophyll proteins (WSCPs) of class IIa from Brassicaceae form tetrameric complexes containing one chlorophyll (Chl) per apoprotein but no carotenoids. The complexes are remarkably stable toward dissociation and protein denaturation even at 100 °C and extreme pH values, and the Chls are partially protected against photooxidation. There are several hypotheses that explain the biological role of WSCPs, one of them proposing that they function as a scavenger of Chls set free upon plant senescence or pathogen attack. The biochemical properties of WSCP described in this paper are consistent with the protein acting as an efficient and flexible Chl scavenger. At limiting Chl concen…