Home About us Contact
|
Home About us Contact | ||
|
|
||
Rapid Pace (rapid + pace)
Selected AbstractsCutaneous melanoma: methods of biopsy and definitive surgical excisionDERMATOLOGIC THERAPY, Issue 5 2005Adam I. Riker ABSTRACT:, The proper method of biopsy and definitive surgical excision of cutaneous melanoma is vital for optimal patient outcome. Clearly, the present authors' understanding of the pathophysiology of cutaneous melanoma continues to change at a rapid pace. Indeed, as the present authors' research efforts begin to expose some of the mysteries of melanoma, so do they begin to better understand the intricacies of this dreaded cancer. This article will highlight methods of biopsy for melanoma and the management of the primary tumor. The present authors review current recommendations for excision margins for the primary tumor, usefulness of lymphoscintigraphy, timing of definitive surgical excision, and issues unique for head and neck melanoma. [source] Experimental study of a doubly-fed rotary frequency converterELECTRICAL ENGINEERING IN JAPAN, Issue 4 2010Yasutoshi Takemoto Abstract Wind power generation using an unlimited, natural energy has been getting attention regarding environmental issues in recent years, and the installed capacity of wind power generation system is increasing at a rapid pace, resulting in deterioration of power quality especially in frequency and voltage. This fact will be a big problem in restricting large capacity of wind farms. This paper proposes a new frequency converter: rotary frequency converter (RFC) to moderate the electric output from wind generation, which is to be installed between a set of wind generators and a grid, providing a smoothed electric output, promoting the wind power generation introduction. This mainly consists of a synchronous machine and the adjustable-speed machine. Independent controls of input/output voltage, active power, and reactive power offer electrical separation between the two networks. Experimental study of a prototype model and its characteristics, especially dynamic control, is discussed in this paper. © 2009 Wiley Periodicals, Inc. Electr Eng Jpn, 170(4): 26,34, 2010; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/eej.20922 [source] Proposed life prediction model for laser-formed high-strength low-alloy curved componentsFATIGUE & FRACTURE OF ENGINEERING MATERIALS AND STRUCTURES, Issue 4 2007P. J. McGRATH ABSTRACT Techniques employed for material processing using laser technology are progressing at a rapid pace. One such technique is that of forming sheet metal plates. This high-intensity localized heating process allows for forming of metallic sheet materials without the need for expensive tools and dies or any mechanical assistance. The fundamental mechanisms related to this process are reasonably well understood and documented but there remain areas that require further research and development. One such area is the fatigue behaviour of sheet materials manufactured by this novel process. Hence, the proceeds of this paper deal with fatigue life prediction of sheet metal components laser-formed to a radius with a curvature of approximately 120 mm. The approach to this proposed model considers the mean stress relationship as given by Gerber and a prediction model derived from combining the aspects of life prediction models according to Collins and Juvinall & Marshek. [source] FTC Goes Wild Over Whole Foods MergerJOURNAL OF CORPORATE ACCOUNTING & FINANCE, Issue 2 2008Robert W. Rouse Despite a credit crunch in 2007, merger and acquisition (M&A) activity has continued at a rapid pace. The two primary regulatory agencies that evaluate proposed mergers,the Department of Justice (DOJ) and the Federal Trade Commission (FTC),issued a guidelines commentary in 2006. It gave us vital insight on how the DOJ and FTC evaluate mergers. The authors review the commentary and show how it worked in the case of one recent acquisition,where the FTC and DOJ disagreed. The authors then discuss how companies can avoid the M&A mistakes of the past. © 2008 Wiley Periodicals, Inc. [source] Global Warming: Can Existing Reserves Really Preserve Current Levels of Biological Diversity?JOURNAL OF INTEGRATIVE PLANT BIOLOGY, Issue 3 2006Mai-He Li Abstract Paleoecological evidence and paleoclimatic records indicate that there was a plant poleward migration in latitude and an upward shift in elevation with increased temperatures after the last glaciation. Recent studies have shown that global warming over the past 100 years has been having a noticeable effect on living systems. Current global warming is causing a poleward and upward shift in the range of many plants and animals. Climate change, in connection with other global changes, is threatening the survival of a wide range of plant and animal species. This raises the question: can existing reserves really preserve current levels of biological diversity in the long term given the present rapid pace of climate change? The present paper deals with this question in the context of the responses of plants and animals to global climate change, based on a literature review. Consequently, we recommend expanding reserves towards the poles and/or towards higher altitudes, to permit species to shift their ranges to keep pace with global warming. (Managing editor: Ya-Qin Han) [source] The role of plant defence proteins in fungal pathogenesisMOLECULAR PLANT PATHOLOGY, Issue 5 2007RICARDO B. FERREIRA SUMMARY It is becoming increasingly evident that a plant,pathogen interaction may be compared to an open warfare, whose major weapons are proteins synthesized by both organisms. These weapons were gradually developed in what must have been a multimillion-year evolutionary game of ping-pong. The outcome of each battle results in the establishment of resistance or pathogenesis. The plethora of resistance mechanisms exhibited by plants may be grouped into constitutive and inducible, and range from morphological to structural and chemical defences. Most of these mechanisms are defensive, exhibiting a passive role, but some are highly active against pathogens, using as major targets the fungal cell wall, the plasma membrane or intracellular targets. A considerable overlap exists between pathogenesis-related (PR) proteins and antifungal proteins. However, many of the now considered 17 families of PR proteins do not present any known role as antipathogen activity, whereas among the 13 classes of antifungal proteins, most are not PR proteins. Discovery of novel antifungal proteins and peptides continues at a rapid pace. In their long coevolution with plants, phytopathogens have evolved ways to avoid or circumvent the plant defence weaponry. These include protection of fungal structures from plant defence reactions, inhibition of elicitor-induced plant defence responses and suppression of plant defences. A detailed understanding of the molecular events that take place during a plant,pathogen interaction is an essential goal for disease control in the future. [source] Acrylamide: An Update on Current Knowledge in Analysis, Levels in Food, Mechanisms of Formation, and Potential Strategies of ControlNUTRITION REVIEWS, Issue 12 2004Richard H. Stadler PhD This review summarizes the research to date on acrylamide levels in food, analytical methods, main sources of dietary exposure, mechanisms of formation, and mitigation research in the major food categories. Significant progress in the research has been made over the past 18 months, as reflected by the numerous publications and national and international workshops on the subject. This rapid pace of developments is mainly attributable to the coordinated and collaborative efforts of all of those concerned: the food industry, academia, private/enforcement laboratories, and national authorities. Most of the information gaps identified since the findings in early 2002 on the occurrence of acrylamide in foods and exposure assessments have been addressed, and public databases have been established by several authorities. Today, the performance of analytical methods, particularly for "difficult" food matrices, is adequate, and any modifications made over the past 12 to 18 months in analytical procedures did not significantly impact the initial exposure calculations. Several avenues into mitigation have been explored in the different food categories, with much emphasis being placed on potato-based products, and empirical trials (mostly pilot studies) have provided better knowledge of the key parameters that influence acrylamide formation. However, despite these intensive efforts, only marginal reductions have been achieved by the food industry, and any further progress will entail long-term studies at the primary production level. Any measures devised to reduce exposure to acrylamide in commercial foods must be carefully assessed in terms of food safety and quality. A hitherto poorly addressed concern is the formation of acrylamide in foods prepared by consumers in the home, and more guidance on this by national authorities is warranted. [source] Oil price movements and globalisation: is there a Connection?OPEC ENERGY REVIEW, Issue 3 2002Robert Looney There has been considerable speculation over the years concerning the cost of large oil price movements ("shocks") to consuming countries. For the advanced industrial countries, the conventional wisdom appears to be that, because these economies are becoming more service,oriented, less energy is needed per unit of gross domestic product (GDP) and hence a lessening of the economic costs associated with increased oil prices. On the other hand, because many newly industrialised or catching,up countries are entering a phase of energy,intensive industrialisation, the same oil shocks are placing an increasing burden on these economies. One can easily argue, however, that industrialisation is only one facet of economic change taking place in the world economy. Conceivably, the rapid pace of increased globalisation may significantly modify these patterns. To test this proposition, an operational definition of globalisation is developed and shown to be positively associated with the strength of oil price shocks. The main finding of the study is that increased globalisation appears to be strengthening the impact of oil price shocks in the advanced industrial countries, but to a much lesser extent in the newly industrialising countries. [source] Cytochromes P450 of insects: the tip of the iceberg,PEST MANAGEMENT SCIENCE (FORMERLY: PESTICIDE SCIENCE), Issue 10 2001Jeffrey G Scott Abstract The cytochrome P450-dependent monooxygenases are an extremely important metabolic system involved in the metabolism of endogenous compounds and xenobiotics. Collectively, P450 monooxygenases can metabolize numerous substrates and carry out multiple oxidative reactions. The large number of substrates metabolized is due to the plethora of P450 isoforms and to the broad substrate specificity of some isoforms. Monooxygenases of insects have several functional roles, including growth, development, feeding and protection against xenobiotics, including resistance to pesticides and tolerance to plant toxins. This review begins with background information about P450s and their evolution, followed by a discussion of the extraordinary diversity of insect P450s. Given the enormous interest in studying individual P450s, we then provide a synopsis of the different methods that have been used in their isolation and the substrates that are known to be metabolized. We conclude by summarizing the lessons we have learned from the study of individual insect P450s, including their roles in insecticide resistance, plant,insect interactions and insect physiology. However, these studies are just the ,tip of the iceberg'. Our knowledge continues to expand at a rapid pace, suggesting that the next decade will outpace the last in terms of improving our understanding of the cytochromes P450 of insects. © 2001 Society of Chemical Industry [source] Biodegradable polymers applied in tissue engineering research: a reviewPOLYMER INTERNATIONAL, Issue 2 2007Monique Martina Abstract Typical applications and research areas of polymeric biomaterials include tissue replacement, tissue augmentation, tissue support, and drug delivery. In many cases the body needs only the temporary presence of a device/biomaterial, in which instance biodegradable and certain partially biodegradable polymeric materials are better alternatives than biostable ones. Recent treatment concepts based on scaffold-based tissue engineering principles differ from standard tissue replacement and drug therapies as the engineered tissue aims not only to repair but also regenerate the target tissue. Cells have been cultured outside the body for many years; however, it has only recently become possible for scientists and engineers to grow complex three-dimensional tissue grafts to meet clinical needs. New generations of scaffolds based on synthetic and natural polymers are being developed and evaluated at a rapid pace, aimed at mimicking the structural characteristics of natural extracellular matrix. This review focuses on scaffolds made of more recently developed synthetic polymers for tissue engineering applications. Currently, the design and fabrication of biodegradable synthetic scaffolds is driven by four material categories: (i) common clinically established polymers, including polyglycolide, polylactides, polycaprolactone; (ii) novel di- and tri-block polymers; (iii) newly synthesized or studied polymeric biomaterials, such as polyorthoester, polyanhydrides, polyhydroxyalkanoate, polypyrroles, poly(ether ester amide)s, elastic shape-memory polymers; and (iv) biomimetic materials, supramolecular polymers formed by self-assembly, and matrices presenting distinctive or a variety of biochemical cues. This paper aims to review the latest developments from a scaffold material perspective, mainly pertaining to categories (ii) and (iii) listed above. Copyright © 2006 Society of Chemical Industry [source] Disorders of left,right asymmetry: Heterotaxy and situs inversus,AMERICAN JOURNAL OF MEDICAL GENETICS, Issue 4 2009Mardi J. Sutherland Abstract Cilia function is critical to the development of proper organ laterality. Primary ciliary dyskinesia (PCD) causes randomization of situs. Heterotaxy, or situs ambiguus, is an abnormal arrangement of the thoracic and abdominal organs that results in congenital anomalies. Animal models and developmental biological approaches have defined pathways required during embryogenesis for proper left,right pattern formation. New candidates for genetic causes of human laterality disorders have emerged from recent studies on the assembly, transport, and signaling functions of cilia at the node as well as identification of cilia within the developing heart. There is evidence that deleterious genetic variants within one or more developmental pathways may disrupt signaling in a synergistic or combinatorial fashion to cause congenital anomalies. The molecular pathways underlying PCD and heterotaxy are being discovered at a rapid pace, and there is increasing recognition of the overlap between these two categories of laterality disorders and their relationship to isolated cardiovascular malformations. This review focuses on the clinical manifestations, molecular mechanisms, and human genetics of these disorders of laterality. © 2009 Wiley-Liss, Inc. [source] The influence of basal metabolic rate on blood pressure among indigenous SiberiansAMERICAN JOURNAL OF PHYSICAL ANTHROPOLOGY, Issue 2 2008J. Josh Snodgrass Abstract Hypertension is an important global health issue and is currently increasing at a rapid pace in most industrializing nations. Although a number of risk factors have been linked with the development of hypertension, including obesity, high dietary sodium, and chronic psychosocial stress, these factors cannot fully explain the variation in blood pressure and hypertension rates that occurs within and between populations. The present study uses data collected on adults from three indigenous Siberian populations (Evenki, Buryat, and Yakut [Sakha]) to test the hypothesis of Luke et al. (Hypertension 43 (2004) 555,560) that basal metabolic rate (BMR) and blood pressure are positively associated independent of body size. When adjusted for body size and composition, as well as potentially confounding variables such as age, smoking status, ethnicity, and degree of urbanization, BMR was positively correlated with systolic blood pressure (SBP; P < 0.01) and pulse pressure (PP; P < 0.01); BMR showed a trend with diastolic blood pressure (DBP; P = 0.08). Thus, higher BMR is associated with higher SBP and PP; this is opposite the well-documented inverse relationship between physical activity and blood pressure. If the influence of BMR on blood pressure is confirmed, the systematically elevated BMRs of indigenous Siberians may help explain the relatively high blood pressures and hypertension rates documented among native Siberians in the post-Soviet period. These findings underscore the importance of considering the influence of biological adaptation to regional environmental conditions in structuring health changes associated with economic development and lifestyle change. Am J Phys Anthropol, 2008. © 2008 Wiley-Liss, Inc. [source] Three-dimensional surface acquisition systems for the study of facial morphology and their application to maxillofacial surgeryTHE INTERNATIONAL JOURNAL OF MEDICAL ROBOTICS AND COMPUTER ASSISTED SURGERY, Issue 2 2007Chung How Kau Abstract Background There has been a growing interest in three-dimensional (3D) surface imaging devices over the last few years. Methods This comprehensive review discusses the various emerging technologies in this field of 3D imaging and applies the use of technology to oral and maxillofacial imaging. Results The paper shows that there is increased awareness and application of technology to the field. Conclusion 3D surface acquisition technology is improving at a rapid pace and has a place in oral and maxillofacial surgery. Copyright © 2007 John Wiley & Sons, Ltd. [source] Brief Overview of BioMicroNano TechnologiesBIOTECHNOLOGY PROGRESS, Issue 1 2005Paul L. Gourley This paper provides a brief overview of the fields of biological micro-electromechanical systems (bioMEMs) and associated nanobiotechnologies, collectively denoted as BioMicroNano. Although they are developing at a very rapid pace and still redefining themselves, several stabilized areas of research and development can be identified. Six major areas are delineated, and specific examples are discussed and illustrated. Various applications of the technologies are noted, and potential market sizes are compared. [source] Climate Change Enhances the Potential Impact of Infectious Disease and Harvest on Tropical WaterfowlBIOTROPICA, Issue 4 2009Lochran W. Traill ABSTRACT Global warming exacerbates threats to biodiversity as ecological systems shift in response to altered climatic conditions. Yet the long-term survival of populations at direct risk from climate change may also be undermined by local factors such as infectious disease or anthropogenic harvest, which leave smaller and more isolated populations increasingly vulnerable to the rapid pace of global change. We review current and future threats to an exemplar tropical waterfowl species, magpie geese Anseranas semipalmata, and focus on the potential synergies between infectious diseases, harvest, and climate change. We outline viral, bacterial, and fungal pathogens likely to cause disease in geese, and give mention to parasites. Further, we elaborate on a previously developed, spatially explicit population viability model to simulate demographic responses to hunting and novel or enhanced disease outbreaks due to climate change. With no harvest, the simulated disease epizootics only threatened metapopulation viability when both mortality rate was high and outbreaks were regular (a threshold response). However, when contemporary site-specific harvest is included as an additive impact, the response to disease severity and probability was linear. We recommend field research to test these hypotheses linking drivers of waterfowl population decline to disease,climate change interactions. [source] | |||||||||||||||||||