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Basic Characteristics (basic + characteristic)
Selected AbstractsBasic characteristics of the population dynamic and state of exploitation of Moroccan white seabream Diplodus sargus cadenati (Sparidae) in the Canarian archipelagoJOURNAL OF APPLIED ICHTHYOLOGY, Issue 1 2004J. G. Pajuelo Summary Moroccan white seabream Diplodus sargus cadenati (n = 603) were caught off the Canary Islands from April 2000 to March 2001. Total length ranged from 46 to 404 mm. The subspecies was characterized as being dygynous with partial protandry. Overall ratio of males to females was 1 : 2.9. The reproductive season extended from December to May, with a peak in spawning activity in January,February. Fifty per cent maturity was reached at 201 mm total length in males and 216 mm in females. The length,weight relationship for all individuals was described by the following parameters: a = 0.000023, and b = 2.96, when length is given in millimeters and weight in grams. Fish of 0,12 years in age were found. The von Bertalanffy growth parameters for the entire population were: L, = 467 mm, k = 0.143 year,1 and t0 = ,2.14 year. Growth parameters differed between males and females. For all fish, instantaneous rates of mortality were Z = 0.68 year,1, M = 0.31 ± 0.6 year,1 and F = 0.37 ± 0.6 year,1; the exploitation ratio was E = 0.54 ± 0.9. Length at first capture for all individuals was 173 mm. The stock exploited above is an assumed optimum. [source] Increased Interleukin-10 and Cortisol in Long-term Alcoholics after Cardiopulmonary Bypass: A Hint to the Increased Postoperative Infection Rate?ALCOHOLISM, Issue 9 2005Michael Sander Background: Previous studies have shown that 20% of all patients admitted to the hospital abuse alcohol and have increased morbidity after surgery. Long-term alcoholic patients are shown to suffer from immune alterations, which might be critical for adequate postoperative performance. Cardiac surgery with cardiopulmonary bypass (CPB) also leads to pronounced immune alteration, which might be linked with patients' ability to combat infections. Therefore, the aim of our study was to investigate the perioperative levels of TNF-alpha, interleukin-6, interleukin-10, and cortisol in long-term alcoholic and nonalcoholic patients undergoing cardiac surgery to elucidate a possible association with postoperative infections. Methods: Forty-four patients undergoing elective cardiac surgery were included in this prospective study. Long-term alcoholic patients (n= 10) were defined as having a daily ethanol consumption of at least 60 g and fulfilling the Diagnostic and Statistical Manual of Mental Disorders for alcohol abuse. The nonalcoholic patients (n= 34) were defined as drinking less than 20 g ethanol per day. Blood samples were obtained to analyze the immune status upon admission to hospital, the morning before surgery and on admission to the ICU, the morning of days one and three after surgery. Results: Basic characteristics of patients did not differ between groups. Long-term alcoholics had a fourfold increase in postsurgery infection rate and prolonged need for ICU treatment and mechanical ventilation. Postoperative levels of interleukin-10 and cortisol were significantly increased in long-term alcoholic patients compared with nonalcoholic patients. These observations were in line with postoperative interleukin-10 being predictive for postoperative infectious complications. Conclusions: The increased infection rate in long-term alcoholics strengthens the urgent need for interventional approaches providing modulation of the perioperative immune and HPA response in these high-risk patients to counteract their postoperative immune suppression. [source] Ordovician Carbonate Reservoir Bed Characteristics and Reservoir-Forming Conditions in the Lungudong Region of the Tarim BasinACTA GEOLOGICA SINICA (ENGLISH EDITION), Issue 5 2010WANG Weili Abstract: Basic characteristics of Ordovician carbonate reservoir beds in the Lungudong region of northeastern part of the Tarim Basin are described in detail and the reservoir-forming conditions of oil and gas are preliminarily discussed in this paper by collecting and sorting out a large amount of data. The carbonate reservoir beds are mainly developed in open-platform and platform marginal facies; the reservoir beds have large changes in and low average values of physical property; the main type is fractured reservoir beds with the fracture-porous type second. The reservoir bed development is chiefly controlled by the distribution of sedimentary facies, tectonic activity and karstification. Whereas the accumulation and distribution of hydrocarbons in the region are controlled by an advantageous structural location, a good reservoir-caprock combination and a favorable transporting system, with the distribution characterized by zones horizontally and belts vertically, the oil and gas are mainly concentrated in areas with structural uplift, densely developed fractures, and surface karst, a vertical vadose zone, and a horizontal undercurrent belt of palaeokarst. [source] Improved upsampling filter design for spatially scalable video codingINTERNATIONAL JOURNAL OF IMAGING SYSTEMS AND TECHNOLOGY, Issue 5 2007Zhang Wang Abstract Scalable video coding is an ongoing standard, and the current working draft (WD) is to be finalized as an extension of H.264/AVC. It provides scalability at the bit stream level with good compression efficiency and allowing free combinations of spatial, temporal and quality scalability. In the WD, a uniform up-sampling filter is employed to interpolate the base layer frames. This technique achieves high interpolated precision for both luma component and chroma components, but it results in extremely large encoding time which obstructs it from practical use. This paper proposes an improved up-sampling filter design for spatially scalable video coding. It makes use of a basic characteristic of human vision system and intends to assign different filters for different components. Specifically, current usage of the 6-tap up-sampling filter is only for luma component, but for chroma components, much more simplified filter such as 4-tap filter or 2-tap filter should be used instead. Experimental results show that improved up-sampling filter design reduces the computational complexity significantly with negligible coding loss and bit-rate increases. © 2008 Wiley Periodicals, Inc. Int J Imaging Syst Technol, 17, 315,319, 2007 [source] A new progressive coding scheme for halftone dithered images using bit-interleavingINTERNATIONAL JOURNAL OF IMAGING SYSTEMS AND TECHNOLOGY, Issue 4 2006Jing-Ming Guo Abstract A novel progressive coding scheme is presented for the efficient display of dithered images. Dithered images are the results of thresholding original gray-level images with dithering screens. After the preprocessing of bit-interleaving, this algorithm utilizes the characteristic of reordered image to determine the transmitting order and then progressively reconstructs the dithered image. In addition, the dithered images are further compressed by lossy and lossless procedures. The experimental results demonstrate high-quality reconstructions while maintaining low transmitted bit rates. Moreover, an objective error criterion obtained by LMS optimization is also presented in this study. As documented in the experiments, the error criterion is quite consistent to the basic characteristic of human visual system. © 2007 Wiley Periodicals, Inc. Int J Imaging Syst Technol, 16, 121,127, 2006. [source] The regulatory state and the UK Labour Government's re-regulation of provision in the English National Health ServiceREGULATION & GOVERNANCE, Issue 4 2009John S. F. Wright Abstract Following its election in 1997, the UK Labour Government embarked upon a 10 year program of reform of the National Health Service (NHS). By 2005, Labour had doubled the NHS budget and dramatically transformed the shape of the Service. In England, a basic characteristic of the NHS is the organizational split between provider and commissioning agencies. In this article I argue that Labour's re-regulation of NHS provision is a coherent representation of the influence of the "regulatory state" in restructuring arrangements between government, market, and society. The article offers an account of the regulatory state based on a discussion of five key theses: The Audit Society, Regulation Inside Government, The New Regulatory State, The British Regulatory State, and Regulatory Capitalism. The article unfolds Labour's program of reform across themes common to these accounts: the division of labor between state and society, the division of labor within the state, the formalization of previously informal controls, and the development of meta-regulatory techniques of enforced self-regulation. It concludes that the key themes of the regulatory state are at work in Labour's transformation of NHS provision and it offers a discussion of the implications for both scholars of regulation and the UK and European health policy literature. [source] Inelastic spectra for infilled reinforced concrete framesEARTHQUAKE ENGINEERING AND STRUCTURAL DYNAMICS, Issue 15 2004Matja Abstract In two companion papers a simplified non-linear analysis procedure for infilled reinforced concrete frames is introduced. In this paper a simple relation between strength reduction factor, ductility and period (R,µ,T relation) is presented. It is intended to be used for the determination of inelastic displacement ratios and of inelastic spectra in conjunction with idealized elastic spectra. The R,µ,T relation was developed from results of an extensive parametric study employing a SDOF mathematical model composed of structural elements representing the frame and infill. The structural parameters, used in the proposed R,µ,T relation, in addition to the parameters used in a usual (e.g. elasto-plastic) system, are ductility at the beginning of strength degradation, and the reduction of strength after the failure of the infills. Formulae depend also on the corner periods of the elastic spectrum. The proposed equations were validated by comparing results in terms of the reduction factors, inelastic displacement ratios, and inelastic spectra in the acceleration,displacement format, with those obtained by non-linear dynamic analyses for three sets of recorded and semi-artificial ground motions. A new approach was used for generating semi-artificial ground motions compatible with the target spectrum. This approach preserves the basic characteristics of individual ground motions, whereas the mean spectrum of the whole ground motion set fits the target spectrum excellently. In the parametric study, the R,µ,T relation was determined by assuming a constant reduction factor, while the corresponding ductility was calculated for different ground motions. The mean values proved to be noticeably different from the mean values determined based on a constant ductility approach, while the median values determined by the different procedures were between the two means. The approach employed in the study yields a R,µ,T relation which is conservative both for design and performance assessment (compared with a relation based on median values). Copyright © 2004 John Wiley & Sons, Ltd. [source] Vertical-type organic device using thin-film ZnO transparent electrodeELECTRICAL ENGINEERING IN JAPAN, Issue 2 2007Hiroyuki Iechi Abstract We propose a double heterojunction organic light-emitting diode (OLED) using a zinc oxide (ZnO) film, which works as a transparent and electron injection layer. The crystal structure of the ZnO films as a function of Ar/O2 flow ratio and the basic characteristics of the OLED depending on the ZnO sputtering conditions are investigated. Excellent characteristics of the novel OLED were obtained, as high as 470 cd/m2 at 22 V and 7.6 mA/cm2. The results obtained here demonstrate that the vertical organic light-emitting transistor (OLET) using a ZnO layer as an electron injection layer is promising as a key element for flexible sheet displays. © 2006 Wiley Periodicals, Inc. Electr Eng Jpn, 158(2): 49,55, 2007; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/eej.20151 [source] European Schoolnet: enabling school networkingEUROPEAN JOURNAL OF EDUCATION, Issue 4 2009SANTI SCIMECA School networking is increasingly important in a globalised world, where schools themselves can be actors on an international stage. This article builds on the activities and experience of the longest established European initiative in this area, European Schoolnet (EUN), a network of 31 Ministries of Education. First, we offer an introduction covering school networks. We then describe the case of European Schoolnet, its history, role, and relationship with other school networks in the world. We then describe the underlying structure of EUN school networks and their basic characteristics. Using these basic characteristics as a framework, we consider a number of eTwinning, European Schoolnet networks: Network of Innovative Schools (ENIS) and myEUROPE. Last, we identify key features of network literacy, potential future trends in school networks, and areas where further research is needed in this field, and offer some recommendations. [source] Theoretical analysis on thermoelectric power generation with rectangular-fin elements and its applicability in micro systemsHEAT TRANSFER - ASIAN RESEARCH (FORMERLY HEAT TRANSFER-JAPANESE RESEARCH), Issue 3 2006Yutaka Oda Abstract A thermoelectric module, which consists of rectangular-fin elements and has a simple structure suitable for micro fabrication, was newly proposed for a micro- to milli-scale thermoelectric power generator. A unit model was introduced to examine the basic characteristics of thermoelectric power generation with rectangular-fin elements. Theoretical descriptions of the power density and conversion efficiency were given by solving one-dimensional heat and current flows inside the elements. Then, it was found that there exist optimum aspect ratios of the elements to achieve maximum power density and conversion efficiency. Power density becomes larger if the module is downsized with a similarity in shape, while conversion efficiency remains constant, i.e., smaller devices show better performance. Finally, comparative analysis with a standard pi-type module was conducted to emphasize the superiority of the proposed module in micro systems, when convective heat transfer resistance is taken into account. © 2006 Wiley Periodicals, Inc. Heat Trans Asian Res, 35(3): 224,244, 2006; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/htj.20108 [source] The stationarity of global mean climateINTERNATIONAL JOURNAL OF CLIMATOLOGY, Issue 7 2004B. G. Hunt Abstract The observed climate exhibits noticeable fluctuations on a range of temporal and spatial scales. Major fluctuations are often attributed to ,external' influences, such as volcanic eruptions or solar perturbations, which obscure climatic fluctuations associated with natural climatic variability generated by internal processes within the climatic system. Although it is difficult to isolate the role of natural climatic variability within the observed climatic system, coupled global climatic models permit such a discrimination to be made in appropriately designed simulations. Thus, the CSIRO coupled global climatic model has been used to determined some basic characteristics of annually averaged global mean climate within a multi-millennial climatic simulation. Some examination of observed climate is also presented. A stationary climatic state was simulated for periods of up to 10 000 years using the CSIRO model, with equilibrium usually being maintained to within 1,2% for all climatic variables investigated. The means by which such stationarity is maintained is analysed and the necessity for rapid negative feedback mechanisms is emphasized. The role of topographically induced climatic features is also discussed. Finally, the implications of the present, presumably greenhouse-related, global warming are considered in the context of the present results. Copyright © 2004 Royal Meteorological Society [source] Prevalence and correlates of alcoholism in community-dwelling elderly living in São Paulo, BrazilINTERNATIONAL JOURNAL OF GERIATRIC PSYCHIATRY, Issue 10 2009Edson Shiguemi Hirata Abstract Objectives To assess the prevalence of alcoholism in elderly living in the city of São Paulo (Brazil) and investigate associated risk factors. Methods A total of 1,563 individuals aged 60 years or older, of both genders of three districts of different socioeconomic classes (high, medium and low) in the city of São Paulo (Brazil) were interviewed. The CAGE screening test for alcoholism was applied and a structured interview was used to assess associated sociodemographic and clinical factors. The tests Mini Mental State Examination, Fuld Object Memory Evaluation, The Informant Questionnaire on Cognitive Decline in the Elderly and Bayer-Activities of Daily Living Scale were used for cognitive and functional assessment. Results Prevalence of alcoholism was 9.1%. Multivariate regression analysis showed that alcoholism was associated with male gender, ,mulatto' ethnicity, smoking, and cognitive and functional impairment. In addition, the younger the individual and the lower the schooling level, the higher the risk for alcoholism. Conclusions The results obtained in this study show that alcoholism is highly frequent in the community-dwelling elderly living in São Paulo, and that it is associated with socio-demographic and clinical risk factors similar to those reported in the literature. This suggests that alcoholism in the elderly of a developing country shares the same basic characteristics seen in developed countries. These findings suggest that it is essential for health services and professional to be prepared to meet this demand that will significantly grow in the next years, especially in developing countries, where the rates of population aging are higher than those of developed countries. Copyright © 2009 John Wiley & Sons, Ltd. [source] An artificial neural network satisfiability testerINTERNATIONAL JOURNAL OF INTELLIGENT SYSTEMS, Issue 12 2001Tatiana Tambouratzis An artificial neural network tester for the satisfiability problem of propositional calculus is presented. Satisfiability is treated as a constraint satisfaction optimization problem and, contrary to most of the existing satisfiability testers, the expressions are converted into disjunctive normal form before testing. The artificial neural network is based on the principles of harmony theory. Its basic characteristics are the simulated annealing procedure and the harmony function; the latter constitutes a measure of the satisfiability of the expression under the current truth assignment to its variables. The tester is such that: (a) the satisfiability of any expression is determined; (b) a truth assignment to the variables of the expression is output which renders true the greatest possible number of clauses; (c) all the truth assignments which render true the maximum number of clauses can be produced. © 2001 John Wiley & Sons, Inc. [source] Histology of the fetal prune belly syndrome with reference to the efficacy of prenatal decompressionINTERNATIONAL JOURNAL OF UROLOGY, Issue 5 2000Kenji Shimada Abstract Background: Deficient abdominal musculature, complex abnormalities of urinary tracts and bilateral abdominal cryptorchidism represent the basic characteristics of prune belly syndrome (PBS). Although prenatal diagnosis of PBS is rarely made, because of the wide variety of ultrasonographic images, reported cases have gradually increased. Once a fetus suspected of having PBS is found, it is sometimes difficult for the pediatric urologists to decide how to treat them. The histology of the kidney and urinary tracts in fetuses with PBS was reviewed in order to give suggestions on the management of prenatal cases. Methods: Autopsy records of nine fetuses (5 males, 2 females and 2 undetermined) with characteristically distended and deficient abdominal wall were reviewed. Gestational age (GA) at detection ranged from 12 to 25 weeks and at delivery from 13 to 32 weeks. Results: Renal histology in two fetuses showed earlier than normal disappearance of cortical nephrogenic zone replaced by cortical cysts and dysplastic structures. The nephrogenic zone was retained in five fetuses which were younger than GA 20 weeks. While the number of glomeruli along the medullary ray was normal for the age in three fetuses younger than GA 20 weeks, it was decreased in all others. Bladder histology was variable showing both increased musculature and defective or dysplastic muscles. There was a tendency for connective tissues in the bladder wall to increase in proportion to GA, The ureter revealed scarcity of muscle bundles among dense connective tissue. The urethra was atretic in eight fetuses. Conclusion: The clinical implication from the renal histology is that decompression of the urinary tract should be done before GA 20 weeks. However, the early fetal treatment appears to have no effect on the urodynamics in this disorder with deficient musculature. [source] Mobile Livelihoods: The Sociocultural Practices of Circular Migrants between Puerto Rico and the United States,INTERNATIONAL MIGRATION REVIEW, Issue 2 2002Jorge Duany This article focuses on the bilateral flow of people between Puerto Rico and the United States - what has come to be known as circular, commuter, or revolving-door migration. It documents the migrants' livelihood practices based on a recent field study of population flows between Puerto Rico and the mainland. Specifically, the basic characteristics of multiple movers, one-time movers and nonmovers residing in Puerto Rico are compared. More broadly, the article assesses the implications of circular migration for Puerto Rican communities on and off the island. The author's basic argument is that the constant displacement of people - both to and from the island - blurs the territorial, linguistic, and juridical boundaries of the Puerto Rican nation. As people expand their means of subsistence across space, they develop multiple attachments to various localities. In the Puerto Rican situation, such mobile livelihoods are easier to establish than in other places because of the free movement of labor and capital between the island and the mainland. The author hypothesizes that circulation does not entail major losses in human capital for most Puerto Ricans, but rather often constitutes an occupational, educational, and linguistic asset. [source] The Spanish public retirement pensions system: Principal challenges and recent developmentsINTERNATIONAL SOCIAL SECURITY REVIEW, Issue 3 2002Francisco Blanco Angel This paper first describes the basic characteristics of the Spanish system of retirement pensions, before addressing its major challenges in the future and the principal solutions proposed. For this purpose, many of the works on social security published in Spain over the past years have been reviewed to provide a recent overview of technical discussions on this subject. Finally, the main reforms undertaken by the government since 1995 are described in some detail and assessed. [source] CONVERTIBLE SECURITIES: A TOLLBOX OF FLEXIBLE FINANCIAL INSTRUMENTS FOR CORPORATE ISSUERSJOURNAL OF APPLIED CORPORATE FINANCE, Issue 1 2000Trevor Ganshaw During the 1990s, convertible and equity-linked securities emerged as a major source of financing for U.S. corporate issuers. Issuance volume grew steadily throughout the decade and the secondary market value of U.S. convertible securities now exceeds $200 billion. In this overview of the market, the authors discuss the following: (1) the growth of issuance volume in the U.S. equity-linked market; (2) the basic characteristics of convertible securities; (3) convertible debt alternatives; and (4) convertible preferred alternatives. As a result of the proliferation of new convertible structures, corporate issuers are now able to adjust coupon/dividend, conversion premium, and call protection in order to meet their tax, accounting, rating agency, and cost-of-capital objectives. Historically, the convertible new issue market has had a broad variety of issuers, spanning all industry sectors as well as both investment grade and high yield credits. But in the last two years, the most aggressive issuers have been technology-oriented companies, including telecommunications, Internet, hardware, software, and biotechnology concerns. Such technology-related issuers, which are often rated below investment grade and unable to secure straight debt capital, are generally in heavy-spending phases and view convertible bonds as a source of inexpensive financing. At the same time, investment-grade, "old-economy" issuers have continued to use convertible securities selectively, in most cases as cheap "quasi-equity" in the context of mergers and acquisitions, or as a tax-deferred strategy for selling cross-holdings of stock. [source] Pharmacokinetics of quinine and its metabolites in pregnant Sudanese women with uncomplicated Plasmodium falciparum malariaJOURNAL OF CLINICAL PHARMACY & THERAPEUTICS, Issue 1 2007I. I. Abdelrahim MSc Summary Objectives:, The study was conducted in New Halfa teaching hospital, eastern Sudan to investigate the pharmacokinetics of quinine in pregnant Sudanese women. Methods:, Sixteen (eight pregnant and eight non-pregnant) Sudanese women infected with Plasmodium falciparum malaria were given a single dose of quinine hydrochloride (10 mg/kg body weight) as intravenous infusion over 2 h. The women were treated with intramuscular artemether. Plasma was collected before quinine administration and up to 72 h thereafter. These were analysed for quinine and its metabolites, 3-hydroxyquinine, (10R)-10,11-dihydroxyquinine and (10S)-10,11-dihydroxyquinine using high-performance liquid chromatography. Results:, The two groups were well matched in their basic characteristics. There was no significant difference in the mean maximum plasma concentration attained (Cmax), the mean time at which Cmax was attained, the elimination half-life (t1/2) and the total area under the plasma concentration vs. time curve (AUC) of quinine and its metabolites between the pregnant in non-pregnant women. Conclusion:, There was no significant difference in quinine metabolism between pregnant and non-pregnant women and there is no need to adjust quinine dose when treating pregnant women. [source] Fabricating autologous tissue to engineer artificial nerveMICROSURGERY, Issue 4 2002Biao Cheng M.D. This study reports on the successful fabrication of artificial nerves with tissue engineering methods. Schwann cells were cultured for 2 weeks, seeded on polyglactin 910 scaffolds, and biomembrane-coated with rat-tail glue and laminin. Observation of the scaffolds' adsorptivity to Schwann cells, and of the growth and migration of Schwann cells, was made using a light microscope, and by scanning and transmission electron microscopy. The Schwann cells were able to migrate and proliferate on the polyglactin 910 fiber. Schwann cells were well-distributed, and formed a Büngner band on which the Schwann cells produced more matrices. Schwann cells on the biomembrane also grew well. We investigated the role of the tissue engineering conduit guide in vivo, using an established rabbit peripheral nerve regeneration model. At 8 weeks, axonal regeneration was observed in the distal nerve stump. Adult Schwann cells can be produced on the coated fiber and the biomembrane. Three-dimensional scaffolds with Schwann cells had the basic characteristics of the artificial nerve. These findings will provide a practical method for fabricating tissue-engineered artificial nerve to repair long nerve defects. © 2002 Wiley-Liss, Inc. MICROSURGERY 22:133,137 2002 [source] Introduction: Second Language Development as a Dynamic ProcessMODERN LANGUAGE JOURNAL, Issue 2 2008KEES DE BOT In this contribution, some of the basic characteristics of complex adaptive systems, collectively labeled Dynamic Systems Theory (DST), are discussed. Such systems are self-organizing, dependent on initial conditions, sometimes chaotic, and they show emergent properties. The focus in DST is on development over time. Language is seen as a dynamic system, and language development, both acquisition and attrition, as a dynamic process. A number of examples of possible applications of DST in the field of applied linguistics are mentioned. After a short presentation of each of the individual articles, some possible lines of research are discussed. [source] Effect of Underlying Heart Disease on the Frequency Content of Ventricular Fibrillation in the Dog HeartPACING AND CLINICAL ELECTROPHYSIOLOGY, Issue 2 2000JASON T. JACOBSON Although prior studies have examined the frequency content of heal electro-gram characteristics during fibrillation, little is know about the effects of underlying heart disease on these parameters. This study was designed to compare the frequency content of local electrograms during VF in canine models of acute ischemia, subacute infarction, and chronic myocardial infarction (MI) to those in control animals to test the hypothesis that underlying heart disease can alter the basic characteristics of VF. VF was induced using burst pacing in three groups of mongrel dogs. Five dogs were evaluated 8 weeks after LAD occlusion MI, five were evaluated 5 days after experimental MI, and 5 had VF induced before (control) and immediately after LAD occlusion (ischemia). During VF, unipolar electrograms were recorded from 112 sites on the anterior LV and electrograms were evaluated 15 and 30 seconds after VF initiation in each group. Electrograms were analyzed by fast Fourier transform. No significant time dependent changes in VF characteristics were noted. The peak frequency was highest in control animals and 8-week MI, intermediate in 5-day MI, and lowest in acute ischemia (P < 0.01 for pairwise comparisons). In contrast, the fractional of energy within a bandwidth of 25% peak amplitude was highest in acute ischemia, (P < 0.001) and similar in the other three groups. Infarction decreased total energy by approximately 50%. In conclusion, the pressure of ischemia or infarction alters the frequency content of VF in a complex fashion. In addition to decreasing the peak frequency, the shape of the power spectral curve is altered in models of structural heart disease. These results suggest that the electrophysiological changes produced by infarction or ischemia alter the structural organization of ventricular fibrillation. [source] Moving dislocations in general anisotropic piezoelectric solidsPHYSICA STATUS SOLIDI (B) BASIC SOLID STATE PHYSICS, Issue 4 2005Ai Kah Soh Abstract The explicit closed-form solution is presented for a moving dislocation with the generalized Burgers vector = [b1, b2, b3, ,,]T in an anisotropic piezoelectric solid, where ,, corresponds to an electric dipole layer along the slip plane. The steady-state version of the Stroh formalism for piezoelectricity is used in this work. Particular attention is paid to the basic characteristics of the electric displacement and electric field due to the moving piezoelectric dislocations. As an important example, a detailed analysis is made for moving dislocations in hexagonal piezoelectric crystals. (© 2005 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] Nitrides as spintronic materialsPHYSICA STATUS SOLIDI (B) BASIC SOLID STATE PHYSICS, Issue 2 2003Tomasz Dietl Abstract A report on the progress in spintronics-related works involving group III nitrides is given, emphasizing contradictory opinions concerning the basic characteristics of these materials. The actual position of magnetic impurities in the GaN lattice as well as a possible role of magnetic precipitates is discussed. The question as to whether the hole introduced by Mn impurities is localized tightly on the Mn d levels or rather on the hybridized p,d bonding states is addressed. The nature of spin,spin interactions and magnetic phases, as provided by theoretical and experimental findings, is outlined and the possible origins of the high-temperature ferromagnetism observed in (Ga, Mn)N are presented. Experimental studies aimed at evaluating characteristic times of spin coherence and dephasing in GaN are described. (© 2003 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] Recent advances in rational gene transfer vector design based on poly(ethylene imine) and its derivativesTHE JOURNAL OF GENE MEDICINE, Issue 8 2005Michael Neu Abstract The continually increasing wealth of knowledge about the role of genes involved in acquired or hereditary diseases renders the delivery of regulatory genes or nucleic acids into affected cells a potentially promising strategy. Apart from viral vectors, non-viral gene delivery systems have recently received increasing interest, due to safety concerns associated with insertional mutagenesis of retro-viral vectors. Especially cationic polymers may be particularly attractive for the delivery of nucleic acids, since they allow a vast synthetic modification of their structure enabling the investigation of structure-function relationships. Successful clinical application of synthetic polycations for gene delivery will depend primarily on three factors, namely (1) an enhancement of the transfection efficiency, (2) a reduction in toxicity and (3) an ability of the vectors to overcome numerous biological barriers after systemic or local administration. Among the polycations presently used for gene delivery, poly(ethylene imine), PEI, takes a prominent position, due to its potential for endosomal escape. PEI as well as derivatives of PEI currently under investigation for DNA and RNA delivery will be discussed. This review focuses on structure-function relationships and the physicochemical aspects of polyplexes which influence basic characteristics, such as complex formation, stability or in vitro cytotoxicity, to provide a basis for their application under in vivo conditions. Rational design of optimized polycations is an objective for further research and may provide the basis for a successful cationic polymer-based gene delivery system in the future. Copyright © 2005 John Wiley & Sons, Ltd. [source] Anaesthetic implications of arrhythmogenic right ventricular dysplasia/cardiomyopathyANAESTHESIA, Issue 1 2009A. K. Alexoudis Summary Arrhythmogenic right ventricular dysplasia, also called right ventricular cardiomyopathy, is a genetically determined heart muscle disease, characterised by life-threatening ventricular arrhythmias in apparently healthy young people. The primary myocardial pathology is that the myocardium of the right ventricular free wall is replaced by fibrous or fibrofatty tissue, with scattered residual myocardial cells. Right ventricular function is abnormal and in severe cases is associated with global right ventricular dilation and overt biventricular heart failure. Although still relatively rare, arrhythmogenic right ventricular cardiomyopathy is a well recognised cause of sudden unexpected peri-operative death. In this review, we describe the basic characteristics of this disease, emphasising the diagnosis and we offer some suggestions for the anaesthetic management of these patients in the peri-operative period. [source] Optimization of data collection taking radiation damage into accountACTA CRYSTALLOGRAPHICA SECTION D, Issue 4 2010Gleb P. Bourenkov To take into account the effects of radiation damage, new algorithms for the optimization of data-collection strategies have been implemented in the software package BEST. The intensity variation related to radiation damage is approximated by log-linear functions of resolution and cumulative X-ray dose. Based on an accurate prediction of the basic characteristics of data yet to be collected, BEST establishes objective relationships between the accessible data completeness, resolution and signal-to-noise statistics that can be achieved in an experiment and designs an optimal plan for data collection. [source] HemoCD as an Artificial Oxygen Carrier: Oxygen Binding and AutoxidationARTIFICIAL ORGANS, Issue 2 2009Koji Kano Abstract Despite many attempts to construct completely artificial systems for carrying oxygen (O2) in aqueous solution, no successful example had been reported until quite recently except for picket fence porphinatoiron(II) embedded in liposomal membrane. We newly prepared a 1:1 complex (hemoCD) of 5,10,15,20-tetrakis(4-sulfonatophenyl)porphinatoiron(II) (Fe[II]TPPS) and a per- O -methylated ,-cyclodextrin dimer having a pyridine linker (Py3CD). HemoCD binds O2 reversibly in aqueous solution. The oxygen affinity corresponding to the partial O2 pressure, at which half of the hemoCD molecules are oxygenated, was 16.9 torr in phosphate buffer at pH 7.0 and 25°C. Oxy-hemoCD was gradually autoxidized (t1/2 = 30.1 h) due to nucleophilic attack of a water molecule to the O2,Fe bond. Encapsulation of the iron center of Fe(II)TPPS by two cyclodextrin truncated cones is essential for binding of O2 to the ferrous center of the porphyrin. This manuscript reports the basic characteristics of hemoCD and the possible future utility of a totally artificial O2 carrier. [source] The future of primary paediatric care in Europe: reflections and Report of the EPA/UNEPSA CommitteeACTA PAEDIATRICA, Issue 1 2010S Barak Abstract Background:, Changes in the scope of the field of paediatrics and the variability in primary paediatric care (PPC) and practice throughout Europe motivated the European Paediatric Association and Union of National European Paediatric Societies and Associations (EPA/UNEPSA) to establish a working group to discuss definitions of paediatric coverage in terms of age limits, find common denominators in the provision of PPC and examine the challenges and goals of 21st century paediatrics relevant to the continent. These issues were presented at the 2008 Europaediatrics in Istanbul, where a consensus declaration was drawn up and accepted by the EPA/UNEPSA Executive Committee. Aim:, To present an outline of the essential elements of the 2008 EPA/UNEPSA Executive Committee consensus declaration. Conclusion:, The definition of basic characteristics and the establishment of requirements for optimal PPC and practice are important steps in overcoming the differences among European countries and pave the way for an acceptable formulation of standardized high-quality paediatric medical care in Europe. [source] | ||||||||||||||||||||||