65 research outputs found
Impact of Commercial Search Engines and International Databases on Engineering Teaching and Research
For the last three decades, the engineering higher education and professional environments have been completely transformed by the "electronic/digital information revolution" that has included the introduction of personal computer, the development of email and world wide web, and broadband Internet connections at home. Herein the writer compares the performances of several digital tools with traditional library resources. While new specialised search engines and open access digital repositories may fill a gap between conventional search engines and traditional references, these should be not be confused with real libraries and international scientific databases that encompass textbooks and peer-reviewed scholarly works. An absence of listing in some Internet search listings, databases and repositories is not an indication of standing. Researchers, engineers and academics should remember these key differences in assessing the quality of bibliographic "research" based solely upon Internet searches
Relationship between p53 mutations and inducible nitric oxide synthase expression in human colorectal cancer.
Parasitological and serological studies on amoebiasis and other intestinal parasitic infections in the rural sector around Recife, Northeast Brazil
How to move ionized gas: an introduction to the dynamics of HII regions
This review covers the dynamic processes that are important in the evolution
and structure of galactic HII regions, concentrating on an elementary
presentation of the physical concepts and recent numerical simulations of HII
region evolution in a non-uniform medium.
The contents are as follows:
(1) The equations (Euler equations; Radiative transfer; Rate equations; How
to avoid the dynamics; How to avoid the atomic physics).
(2) Physical concepts (Static photoionization equilibrium; Ionization front
propagation; Structure of a D-type front; Photoablation flows; Other
ingredients - Stellar winds, Radiation pressure, Magnetic fields,
Instabilities).
(3) HII region evolution (Early phases: hypercompact and ultracompact
regions; Later phases: compact and extended regions; Clumps and turbulence).Comment: To be published as a chapter in 'Diffuse Matter from Star Forming
Regions to Active Galaxies' - A volume Honouring John Dyson. Eds. T. W.
Harquist, J. M. Pittard and S. A. E. G. Falle. 25 pages, 7 figures. Some
figures degraded to meet size restriction. Full-resolution version available
at http://www.ifront.org/wiki/Dyson_Festschrift_Chapte
Stakeholder identification in the planning phase of aggregate and quarrying projects
The need to accommodate social and environ- mental parameters in planning new quarrying activities is becoming increasingly apparent in modern societies in order to improve sustaina- bility of the sector and manage social risk. In- volvement of all interested stakeholders from the early stages of the planning phase is an inte- gral part of the "social license" which is earned and allows the society to monitor and measure the performance of the project and the company throughout the quarry life cycle. The planning process should include an in depth analysis of all political, economic, social and technological factors involved. This paper aims to discuss the most important issues related to stakeholder identification and analysis and the way this pro- cess can be improved for the benefit of both the company and the society. It is believed that such an approach also allows companies to achieve realistic views of the concerns of the people and the way they value their environment within the area of potential quarry developmen
Stakeholder identification in the planning phase of aggregate and quarrying projects
The need to accommodate social and environ- mental parameters in planning new quarrying activities is becoming increasingly apparent in modern societies in order to improve sustaina- bility of the sector and manage social risk. In- volvement of all interested stakeholders from the early stages of the planning phase is an inte- gral part of the “social license” which is earned and allows the society to monitor and measure the performance of the project and the company throughout the quarry life cycle. The planning process should include an in depth analysis of all political, economic, social and technological factors involved. This paper aims to discuss the most important issues related to stakeholder identification and analysis and the way this pro- cess can be improved for the benefit of both the company and the society. It is believed that such an approach also allows companies to achieve realistic views of the concerns of the people and the way they value their environment within the area of potential quarry development
Frequent nitric oxide synthase-2 expression in human colon adenomas: implication for tumor angiogenesis and colon cancer progression.
An increased expression of nitric oxide synthase (NOS) has been observed in human colon carcinoma cell lines as well as in human gynecological, breast, and central nervous system tumors. This observation suggests a pathobiological role of tumor-associated NO production. Hence, we investigated NOS expression in human colon cancer in respect to tumor staging, NOS-expressing cell type(s), nitrotyrosine formation, inflammation, and vascular endothelial growth factor expression. Ca2+-dependent NOS activity was found in normal colon and in tumors but was significantly decreased in adenomas (P < 0.001) and carcinomas (Dukes' stages A-D: P < 0.002). Ca2+-independent NOS activity, indicating inducible NOS (NOS2), is markedly expressed in approximately 60% of human colon adenomas (P < 0.001 versus normal tissues) and in 20-25% of colon carcinomas (P < 0.01 versus normal tissues). Only low levels were found in the surrounding normal tissue. NOS2 activity decreased with increasing tumor stage (Dukes' A-D) and was lowest in colon metastases to liver and lung. NOS2 was detected in tissue mononuclear cells (TMCs), endothelium, and tumor epithelium. There was a statistically significant correlation between NOS2 enzymatic activity and the level of NOS2 protein detected by immunohistochemistry (P < 0.01). Western blot analysis of tumor extracts with Ca2+-independent NOS activity showed up to three distinct NOS2 protein bands at Mr 125,000-Mr 138,000. The same protein bands were heavily tyrosine-phosphorylated in some tumor tissues. TMCs, but not the tumor epithelium, were immunopositive using a polyclonal anti-nitrotyrosine antibody. However, only a subset of the NOS2-expressing TMCs stained positively for 3-nitrotyrosine, which is a marker for peroxynitrite formation. Furthermore, vascular endothelial growth factor expression was detected in adenomas expressing NOS2. These data are consistent with the hypothesis that excessive NO production by NOS2 may contribute to the pathogenesis of colon cancer progression at the transition of colon adenoma to carcinoma in situ
- …