Scientific Background (scientific + background)

Distribution by Scientific Domains


Selected Abstracts


Genetic analysis of early neurogenesis: Dedicated to the scientific contributions of Jose A. Campos-Ortega (1940,2004),

DEVELOPMENTAL DYNAMICS, Issue 7 2006
Volker Hartenstein
Abstract Jose Campos-Ortega stands out as one of the pioneers of developmental-genetic studies of early neurogenesis. He also liked to reflect about the history of science: how one discovery leads to the next, and what role individuals play in the progress of science. He had indeed started to work on a book describing the history of developmental genetics during the last year of his life. His goal in this book was to "explain how developmental genetics originated, how it transformed developmental biology and, while doing so, how it contributed to achieve the biological synthesis." In the following, I would like to reflect on the origin and growth of the field Campos-Ortega contributed so much. In doing so, it is of particular interest to consider his scientific roots, and the manner in which he entered the stage of developmental genetics. I believe that Campos-Ortega's unusual scientific background influenced in an important manner the way in which he shaped the study of early neurogenesis. Developmental Dynamics 235:2003,2008, 2006. © 2006 Wiley-Liss, Inc. [source]


Perpest model, a case-based reasoning approach to predict ecological risks of pesticides

ENVIRONMENTAL TOXICOLOGY & CHEMISTRY, Issue 11 2002
Paul J. Van den Brink
Abstract The PERPEST model is a model that predicts the ecological risks of pesticides in freshwater ecosystems. This model simultaneously predicts the effects of a particular concentration of a pesticide on various (community) endpoints. In contrast to most effect models, PERPEST is based on empirical data extracted from the literature. This model is based on case-based reasoning, a technique that solves new problems (e.g., what is the effect of pesticide A?) by using past experience (e.g., published microcosm experiments). The database containing the past experience has been constructed by performing a review of freshwater model ecosystem studies. This review assessed the effects on various endpoints (e.g., community metabolism, phytoplankton, and macroinvertebrates) and classified them according to their magnitude and duration. The PERPEST model searches for analogous situations in the database, based on relevant (toxicity) characteristics of the compound. This allows the model to predict effects of pesticides for which no effects on a semifield scale have been published. The PERPEST model results in a prediction showing the probability of classes of effects (no, slight, or clear effects, plus an optional indication of recovery) on the various grouped endpoints. This paper discusses the scientific background of the model as well as its strengths, limitations, and possible applications. [source]


Less-oxidative hemodialysis solution rendered by cathode-side application of electrolyzed water

HEMODIALYSIS INTERNATIONAL, Issue 3 2007
Masaaki NAKAYAMA
Abstract Electrolyzed water (EW) generated on the cathode side reportedly displays anti-oxidative properties, and application of EW to hemodialysis (HD) systems supposedly suppresses oxidative markers in patients on HD. However, most of the chemical properties and biological effects of such solutions remain unclear. This study aimed to examine those issues to clarify the scientific background for the clinical use of EW solution. Reverse osmosis water comprising EW from the cathode side (e-RO) was prepared and used to process a test HD solution (e-HD). Chemical and biological properties of these solutions were compared with controls. Redox properties were examined by chemiluminescence (CL) of the luminol-H2O2 system. Biological effects of e-RO on human polymorphonuclear leukocytes (PMNs) were tested with respect to the cellular protection against methylglyoxal, and with respect to the preservation of cellular function as to radical generation. Control HD solution presented the highest CL, followed by e-HD, control RO, suggesting a lower oxidative capacity for EW-based solutions. Increased levels of dissolved hydrogen were characteristic of e-RO and e-HD. Application of e-RO tended to be associated with less injury of PMNs by methylglyoxal, and with significantly higher levels of radical generation compared with the control. Compared with control HD, e-RO-based HD solution displays less-oxidative capacity in chemical terms, and may at least partly facilitate preservation of PMN viability. These results appear to offer a scientific basis for supporting the clinical challenge of applying this technology to HD treatment. [source]


Flood-related disaster vulnerability: an impending crisis of megacities in Asia

JOURNAL OF FLOOD RISK MANAGEMENT, Issue 3 2010
Y. Adikari
Abstract The megacities around the world have been located in fertile river basins since the beginning of civilization. In recent years, population has been increasing drastically; as a result, people migrate to cities and live in vulnerable and marginal areas, thus giving rise to slums. Therefore, we would like to point out why and how megacities in Asia are vulnerable to flood. The vulnerability of the cities, especially the slums, is shaped by forces such as global changes, internal migration patterns, development practices and political instability, which constantly reshape the risk of floods, which may be frequent and disastrous. Hence, development choices with a strong scientific background, especially in the cities prone to monsoon, are necessary to protect development, and not only floods but all disaster risks should be regulated and mainstreamed into the development planning of cities. [source]


Recent advances in chemical peeling in Japan

THE JOURNAL OF DERMATOLOGY, Issue 10 2006
Fukumi FURUKAWA
ABSTRACT Chemical peeling is one of the dermatological treatments available for certain cutaneous diseases and conditions or aesthetic improvement. This treatment consists of the application of one or more chemical agents to the skin. Recently in Japan, chemical peeling has been very popular for medical as well as aesthetic treatment. Because the scientific background and an adequate approach have not been completely established, medical and social problems have been reported. To address these issues, the Japanese Dermatological Association has established standard guidelines for chemical peeling, and the scientific background and validity of chemical peeling has been assessed. In this review, a set of guidelines for chemical peeling is introduced, and we will discuss several clinical and histological studies including the effects of glycolic acid, and the application of deer peeling to skin tumors in our department. [source]


A concept for a satellite mission to measure cloud ice water path, ice particle size, and cloud altitude,

THE QUARTERLY JOURNAL OF THE ROYAL METEOROLOGICAL SOCIETY, Issue S2 2007
S. A. Buehler
Abstract A passive satellite radiometer operating at submillimetre wavelengths can measure cloud ice water path (IWP), ice particle size, and cloud altitude. The paper first discusses the scientific background for such measurements. Formal scientific mission requirements are derived, based on this background and earlier assessments. The paper then presents a comprehensive prototype instrument and mission concept, and demonstrates that it meets the requirements. The instrument is a conically scanning 12-channel radiometer with channels between 183 and 664 GHz, proposed to fly in tandem with one of the Metop satellites. It can measure IWP with a relative accuracy of approximately 20% and a detection threshold of approximately 2 g m,2. The median mass equivalent sphere diameter of the ice particles can be measured with an accuracy of approximately 30 µm, and the median IWP cloud altitude can be measured with an accuracy of approximately 300 m. All the above accuracies are median absolute error values; root mean square error values are approximately twice as high, due to rare outliers. Copyright © 2007 Royal Meteorological Society [source]


Going to the Roots of the Stem Cell Controversy

BIOETHICS, Issue 6 2002
Søren Holm
The purpose of this paper is to describe the scientific background to the current ethical and legislative debates about the generation and use of human stem cells, and to give an overview of the ethical issues underlying these debates. The ethical issues discussed are 1) stem cells and the status of the embryo, 2) women as the sources of ova for stem cell production, 3) the use of ova from other species, 4) slippery slopes towards reproductive cloning, 5) the public presentation of stem cell research and 6) the evaluation of scientific uncertainty and its implications for public policy. [source]


Vitamin D3 upregulated protein 1 (VDUP1) is a regulator for redox signaling and stress-mediated diseases

THE JOURNAL OF DERMATOLOGY, Issue 10 2006
Jin Woong CHUNG
ABSTRACT Vitamin D3 upregulated protein 1 (VDUP1) is a 46-kDa multifunctional protein, initially isolated in HL-60 cells as a protein of which expression is upregulated by vitamin D3 administration. Subsequently, it was identified independently by investigators from diverse scientific backgrounds as a thioredoxin binding protein that negatively regulates the expression and the activity of thioredoxin, and is thus involved in redox regulation. Further studies have revealed that VDUP1 plays multiple roles in a wide range of cellular processes such as proliferation or apoptosis. Recently, it has been reported that VDUP1 is also involved in the immune system via positive regulation of natural killer development. In addition, VDUP1 has been revealed to be associated with the fatty acid utilization. In the present review, we discuss the novel aspects of VDUP1 function as well as the historical background of VDUP1. Future studies will explore the diagnostic and therapeutic potential of modulating the function of VDUP1 in vivo. [source]