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Selected AbstractsAtrial Endocarditis,The Importance of the Regurgitant Jet LesionECHOCARDIOGRAPHY, Issue 5 2005Shawn A. Gregory M.D. The jet lesions of valvular regurgitation or intracardiac shunts have been hypothesized to play an important role in the pathogenesis of endocarditis for many years. We describe a case of mitral valve endocarditis that involved the left atrium along the path of a jet lesion. This resulted in atrial endocarditis and pericarditis, both of which complicated her presentation and hospital course. Using transesophageal echocardiography, we were able to directly visualize the path and full extent of infection prior to surgery. Special attention should be focused upon the path of eccentric jets in order to fully define the extent of endocarditis. [source] Claustral Lesions Delay Amygdaloid Kindling in the RatEPILEPSIA, Issue 9 2000Paul Mohapel Summary: Purpose: Lesions of the claustrum in cats and primates have been shown to disrupt the development and expression of amygdaloid-kindled seizures in cats and primates. Because the structure and connectivity of the claustrum can vary between species, we wanted to examine the effects of claustral lesions on kindling in rats. Methods: One group of rats received bilateral radiofrequency lesions of both anterior and posterior regions of the claustrum before amygdaloid kindling. Another group of rats received bilateral anterior and posterior radiofrequency lesions of the claustrum after amygdaloid kindling. Some rats were tested for transfer of kindling to the contralateral amygdala after claustral lesions. Results: Small lesions that destroyed 13% of the claustrum were capable of delaying, but not blocking, amygdaloid kindling. The delay in kindling was due to an increase in the stimulation trials required to kindle to stage 5 seizures. The lesions had no effect on established kindled seizures or on transfer to the contralateral amygdala. Conclusions: As in other species, the claustrum in the rat appears to play a role in kindling from the amygdala. Because of the restricted size of our claustral lesions, however, we were unable to conclusively assess the full extent of the claustrum's participation in limbic kindling. [source] Expression of trunk Hox genes in the centipede Strigamia maritima: sense and anti-sense transcriptsEVOLUTION AND DEVELOPMENT, Issue 3 2006Carlo Brena SUMMARY We report the coding sequence and embryonic expression of the four trunk Hox genes Antennapedia (Antp), Ultrabithorax (Ubx), abdominal-A (abd-A), and Abdominal-B (Abd-B) in the geophilomorph centipede Strigamia maritima. In geophilomorph centipedes, all leg-bearing segments (LBS) are generated during embryogenesis, allowing us to define expression in relation to the full extent of the forming trunk. Persistent Antp expression characterizes the maxillipedal (poison claw) segment, whereas all LBS express the three Hox genes Antp, Ubx, and abd-A. Abd-B is never detectably expressed in segmented tissue, but is restricted to a zone around the proctodaeum that contributes to the hindgut. Expression of all these Hox genes initiates in the unsegmented tissue of the blastodisc, with expression of Antp respecting a sharply defined anterior border before the appearance of morphological segmentation in the trunk. The accumulation of Hox gene transcripts is strongly modulated by the maturing segment pattern, suggesting regulatory interactions with multiple levels of the segment patterning machinery. For one of these genes, Ubx, we detect both sense and anti-sense transcripts. The anti-sense transcripts originate 3, to the Ubx coding sequence and overlap the homeobox exon; they are expressed earlier than the Ubx coding transcripts and persistently, in an axially restricted pattern comparable to but distinct from those of the Hox coding transcripts. The pattern of accumulation of Ubx sense and anti-sense transcripts is strikingly complementary, suggesting the possibility of anti-sense regulation of Ubx expression. [source] Insect glutathione transferases and insecticide resistanceINSECT MOLECULAR BIOLOGY, Issue 1 2005A. A. Enayati Abstract Glutathione transferases (GSTs) are a diverse family of enzymes found ubiquitously in aerobic organisms. They play a central role in the detoxification of both endogenous and xenobiotic compounds and are also involved in intracellular transport, biosynthesis of hormones and protection against oxidative stress. Interest in insect GSTs has primarily focused on their role in insecticide resistance. GSTs can metabolize insecticides by facilitating their reductive dehydrochlorination or by conjugation reactions with reduced glutathione, to produce water-soluble metabolites that are more readily excreted. In addition, they contribute to the removal of toxic oxygen free radical species produced through the action of pesticides. Annotation of the Anopheles gambiae and Drosophila melanogaster genomes has revealed the full extent of this enzyme family in insects. This mini review describes the insect GST enzyme family, focusing specifically on their role in conferring insecticide resistance. [source] Water vapour transport associated with tropical,temperate trough systems over southern Africa and the southwest Indian OceanINTERNATIONAL JOURNAL OF CLIMATOLOGY, Issue 5 2004Martin C. Todd Abstract Tropical,temperate trough (TTT) systems are the dominant rain-producing synoptic type over southern Africa. They represent an important mechanism of poleward transport of energy and momentum. This paper provides an analysis of water vapour transport in TTT systems. An objective sampling of TTT systems is conducted from analysis of daily satellite rainfall products. During the sampled TTT events, rain bands extend from tropical southern Africa near 10 °S to the midlatitudes of the southwest Indian Ocean. The divergent and non-divergent (streamfunction) components of vertically integrated water vapour flux associated with major TTT events are calculated, from National Centers for Environmental Prediction reanalysis data. During TTT events the streamfunction circulation dominates water vapour transport, although adjustments to the divergent component are relatively more important. The results indicate that TTT events facilitate a substantial water vapour flux from the tropics into the midlatitudes. Water vapour transport to the midlatitudes along the TTT axis is facilitated largely by changes to the streamfunction, associated with a strengthening and eastward displacement of the Indian Ocean high, and the advent of midlatitude transients. It is also shown that TTT systems are major regions of moisture convergence. The high vapour concentrations along the full extent of the TTT rain bands are maintained by the divergent circulation. The structure of these divergent vapour flux anomalies is suggestive of adjustments to the Walker circulation, involving strong anomalous divergence over the maritime continent/west Pacific and a weaker enhancement of the major divergence centre over the tropical Atlantic. Copyright © 2004 Royal Meteorological Society [source] Spatial abundance structures in an assemblage of gall-forming sawfliesJOURNAL OF ANIMAL ECOLOGY, Issue 3 2004M. A. McGeoch Summary 1Examination of the fine-scale internal structure of species geographical ranges, and interspecific variation therein across landscapes, contributes to a more comprehensive understanding of the structure of geographical ranges. Two components of this internal structure that require further examination are the occurrence, extent and position of spatial autocorrelation, and relationships between the spatial abundance structures of closely related, ecologically similar species. 2Here we compare the abundance structures of an assemblage of gall-forming sawflies (Tenthredinidae) across a landscape. We identify the relative roles of spatial and non-spatial factors in explaining their abundance structures and test the hypothesis that sawfly density is explained by host plant quality, as has been demonstrated repeatedly at finer scales. We use these results to distinguish between alternative sets of mechanisms that may be operating at the landscape scale. 3Species densities were mainly multimodal across the landscape and significantly spatially structured, with patch, periodic and trend components. The abundance structures thus mimic those found generally for species across the full extent of their geographical ranges. 4Many abundance structure characteristics were unique to species, with differences in their correlogram profiles, distances over which densities were positively autocorrelated, and the absence of significant spatial structure in one species. 5In contrast to previous, fine-scale studies, host plant quality explained little of the variation in sawfly gall density across the landscape, whereas unexplained spatial structure contributed between 30% and 50%. Based on knowledge of the biology of these species and the absence of competitive interactions, species dispersal characteristics and the Moran effect are suggested as probable alternative hypotheses at this scale. 6Therefore, a spatial approach has identified the hierarchical nature of mechanisms underlying the population dynamics of this sawfly assemblage for the first time. Furthermore, it has highlighted the importance of spatial processes in explaining the densities of species at the landscape scale, as well as the individualistic nature of their abundance structures. [source] The status of training and education in information and computer technology of Australian nurses: a national surveyJOURNAL OF CLINICAL NURSING, Issue 20 2008Robert Eley Aims and objectives., A study was undertaken of the current knowledge and future training requirements of nurses in information and computer technology to inform policy to meet national goals for health. Background., The role of the modern clinical nurse is intertwined with information and computer technology and adoption of such technology forms an important component of national strategies in health. The majority of nurses are expected to use information and computer technology during their work; however, the full extent of their knowledge and experience is unclear. Design., Self-administered postal survey. Methods., A 78-item questionnaire was distributed to 10,000 Australian Nursing Federation members to identify the nurses' use of information and computer technology. Eighteen items related to nurses' training and education in information and computer technology. Results., Response rate was 44%. Computers were used by 86·3% of respondents as part of their work-related activities. Between 4,17% of nurses had received training in each of 11 generic computer skills and software applications during their preregistration/pre-enrolment and between 12,30% as continuing professional education. Nurses who had received training believed that it was adequate to meet the needs of their job and was given at an appropriate time. Almost half of the respondents indicated that they required more training to better meet the information and computer technology requirements of their jobs and a quarter believed that their level of computer literacy was restricting their career development. Nurses considered that the vast majority of employers did not encourage information and computer technology training and, for those for whom training was available, workload was the major barrier to uptake. Nurses favoured introduction of a national competency standard in information and computer technology. Conclusions., For the considerable benefits of information and computer technology to be incorporated fully into the health system, employers must pay more attention to the training and education of nurses who are the largest users of that technology. Relevance to clinical practice., Knowledge of the training and education needs of clinical nurses with respect to information and computer technology will provide a platform for the development of appropriate policies by government and by employers. [source] Impact of Chronic Alcohol Ingestion on Cardiac Muscle Protein ExpressionALCOHOLISM, Issue 7 2010Rachel L. Fogle Background:, Chronic alcohol abuse contributes not only to an increased risk of health-related complications, but also to a premature mortality in adults. Myocardial dysfunction, including the development of a syndrome referred to as alcoholic cardiomyopathy, appears to be a major contributing factor. One mechanism to account for the pathogenesis of alcoholic cardiomyopathy involves alterations in protein expression secondary to an inhibition of protein synthesis. However, the full extent to which myocardial proteins are affected by chronic alcohol consumption remains unresolved. Methods:, The purpose of this study was to examine the effect of chronic alcohol consumption on the expression of cardiac proteins. Male rats were maintained for 16 weeks on a 40% ethanol-containing diet in which alcohol was provided both in drinking water and agar blocks. Control animals were pair-fed to consume the same caloric intake. Heart homogenates from control- and ethanol-fed rats were labeled with the cleavable isotope coded affinity tags (ICATÔ). Following the reaction with the ICATÔ reagent, we applied one-dimensional gel electrophoresis with in-gel trypsin digestion of proteins and subsequent MALDI-TOF-TOF mass spectrometric techniques for identification of peptides. Differences in the expression of cardiac proteins from control- and ethanol-fed rats were determined by mass spectrometry approaches. Results:, Initial proteomic analysis identified and quantified hundreds of cardiac proteins. Major decreases in the expression of specific myocardial proteins were observed. Proteins were grouped depending on their contribution to multiple activities of cardiac function and metabolism, including mitochondrial-, glycolytic-, myofibrillar-, membrane-associated, and plasma proteins. Another group contained identified proteins that could not be properly categorized under the aforementioned classification system. Conclusions:, Based on the changes in proteins, we speculate modulation of cardiac muscle protein expression represents a fundamental alteration induced by chronic alcohol consumption, consistent with changes in myocardial wall thickness measured under the same conditions. [source] Concepts and semantic relations in information scienceJOURNAL OF THE AMERICAN SOCIETY FOR INFORMATION SCIENCE AND TECHNOLOGY, Issue 10 2010Wolfgang G. Stock Concept-based information retrieval and knowledge representation are in need of a theory of concepts and semantic relations. Guidelines for the construction and maintenance of knowledge organization systems (KOS) (such as ANSI/NISO Z39.19-2005 in the U.S.A. or DIN 2331:1980 in Germany) do not consider results of concept theory and theory of relations to the full extent. They are not able to unify the currently different worlds of traditional controlled vocabularies, of the social web (tagging and folksonomies) and of the semantic web (ontologies). Concept definitions as well as semantic relations are based on epistemological theories (empiricism, rationalism, hermeneutics, pragmatism, and critical theory). A concept is determined via its intension and extension as well as by definition. We will meet the problem of vagueness by introducing prototypes. Some important definitions are concept explanations (after Aristotle) and the definition of family resemblances (in the sense of Wittgenstein). We will model concepts as frames (according to Barsalou). The most important paradigmatic relation in KOS is hierarchy, which must be arranged into different classes: Hyponymy consists of taxonomy and simple hyponymy, meronymy consists of many different part-whole-relations. For practical application purposes, the transitivity of the given relation is very important. Unspecific associative relations are of little help to our focused applications and should be replaced by generalizable and domain-specific relations. We will discuss the reflexivity, symmetry, and transitivity of paradigmatic relations as well as the appearance of specific semantic relations in the different kinds of KOS (folksonomies, nomenclatures, classification systems, thesauri, and ontologies). Finally, we will pick out KOS as a central theme of the Semantic Web. [source] The Cross-linguistic Study of Sentence ProductionLINGUISTICS & LANGUAGE COMPASS (ELECTRONIC), Issue 4 2009T. Florian Jaeger The mechanisms underlying language production are often assumed to be universal, and hence not contingent on a speaker's language. This assumption is problematic for at least two reasons. Given the typological diversity of the world's languages, only a small subset of languages has actually been studied psycholinguistically. And, in some cases, these investigations have returned results that at least superficially raise doubt about the assumption of universal production mechanisms. The goal of this paper is to illustrate the need for more psycholinguistic work on a typologically more diverse set of languages. We summarize cross-linguistic work on sentence production (specifically: grammatical encoding), focusing on examples where such work has improved our theoretical understanding beyond what studies on English alone could have achieved. But cross-linguistic research has much to offer beyond the testing of existing hypotheses: it can guide the development of theories by revealing the full extent of the human ability to produce language structures. We discuss the potential for interdisciplinary collaborations, and close with a remark on the impact of language endangerment on psycholinguistic research on understudied languages. [source] A census of young stellar populations in the warm ULIRG PKS 1345+12MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY, Issue 4 2007J. Rodríguez Zaurín ABSTRACT We present a detailed investigation of the young stellar populations (YSP) in the radio-loud ultraluminous infrared galaxy (ULIRG), PKS 1345+12 (z= 0.12), based on high-resolution Hubble Space Telescope (HST) imaging and long-slit spectra taken with the William Herschel Telescope (WHT) at La Palma. While the images clearly show bright knots suggestive of super star clusters (SSCs), the spectra reveal the presence of YSP in the diffuse light across the full extent of the halo of the merging double nucleus system. Spectral synthesis modelling has been used to estimate the ages of the YSP for both the SSC and the diffuse light sampled by the spectra. For the SSC, we find ages tSSC < 6 Myr with reddenings 0.2 < E(B,V) < 0.5 and masses 106 < MYSPSSC < 107 M,. In the region to the south of the western nucleus that contains the SSC our modelling of the spectrum of the diffuse light is also consistent with a relatively young age for the YSP (,5 Myr), although older YSP ages cannot be ruled out. However, in other regions of the galaxy we find that the spectra of the diffuse light component can only be modelled with a relatively old post-starburst YSP (0.04,1.0 Gyr) or with a disc galaxy template spectrum. The results demonstrate the importance of accounting for reddening in photometric studies of SSC and highlight the dangers of focusing on the highest surface brightness regions when trying to obtain a general impression of the star formation activity in the host galaxies of ULIRGs. The case of PKS 1345+12 provides clear evidence that the star formation histories of the YSP in ULIRGs are complex. While the SSC represent the vigorous phase of star formation associated with the final stages of the merger, the YSP in the diffuse light are likely to represent star formation in one or more of the merging galaxies at an earlier stage or prior to the start of the merger. Intriguingly, our long-slit spectra show line splitting at the locations of the SSC, indicating that they are moving at up to 450 km s,1 with respect to the local ambient gas. Given their kinematics, it is plausible that the SSCs have been formed either in fast moving gas streams/tidal tails that are falling back into the nuclear regions as part of the merger process or as a consequence of jet-induced star formation linked to the extended, diffuse radio emission detected in the halo of the galaxy. [source] Exploring adolescent perceptions of parental beliefs and practices related to friendships in diverse ethnic communitiesNEW DIRECTIONS FOR CHILD & ADOLESCENT DEVELOPMENT, Issue 116 2007Niobe Way It is important to examine both the belief systems and the practices of parents in regard to adolescent friendships. Belief systems inform parental practices and also reveal the full extent of cultural variations that exist within and across ethnic communities. [source] A review of the effectiveness of aspartame in helping with weight controlNUTRITION BULLETIN, Issue 2 2006A. De La Hunty Summary, Strategies to reverse the upward trend in obesity rates need to focus on both reducing energy intake and increasing energy expenditure. The provision of low- or reduced-energy-dense foods is one way of helping people to reduce their energy intake and so enable weight maintenance or weight loss to occur. The use of intense sweeteners as a substitute for sucrose potentially offers one way of helping people to reduce the energy density of their diet without any loss of palatability. This report reviews the evidence for the effect of aspartame on weight loss, weight maintenance and energy intakes in adults and addresses the question of how much energy is compensated for and whether the use of aspartame-sweetened foods and drinks is an effective way to lose weight. All studies which examined the effect of substituting sugar with either aspartame alone or aspartame in combination with other intense sweeteners on energy intake or bodyweight were identified. Studies which were not randomised controlled trials in healthy adults and which did not measure energy intakes for at least 24 h (for those with energy intakes as an outcome measure) were excluded from the analysis. A minimum of 24-h energy intake data was set as the cut-off to ensure that the full extent of any compensatory effects was seen. A total of 16 studies were included in the analysis. Of these 16 studies, 15 had energy intake as an outcome measure. The studies which used soft drinks as the vehicle for aspartame used between 500 and about 2000 ml which is equivalent to about two to six cans or bottles of soft drinks every day. A significant reduction in energy intakes was seen with aspartame compared with all types of control except when aspartame was compared with non-sucrose controls such as water. The most relevant comparisons are the parallel design studies which compare the effects of aspartame with sucrose. These had an overall effect size of 0.4 standardised difference (SD). This corresponds to a mean reduction of about 10% of energy intake. At an average energy intake of 9.3 MJ/day (average of adult men and women aged 19,50 years) this is a deficit of 0.93 MJ/day (222 kcal/day or 1560 kcal/week), which would be predicted (using an energy value for obese tissue of 7500 kcal/kg) to result in a weight loss of around 0.2 kg/week with a confidence interval 50% either side of this estimate. Information on the extent of compensation was available for 12 of the 15 studies. The weighted average of these figures was 32%. Compensation is likely to vary with a number of factors such as the size of the caloric deficit, the type of food or drink manipulated, and timescale. An estimate of the amount of compensation with soft drinks was calculated from the four studies which used soft drinks only as the vehicle. A weighted average of these figures was 15.5%. A significant reduction in weight was seen. The combined effect figure of 0.2 SD is a conservative figure as it excludes comparisons where the controls gained weight because of their high-sucrose diet and the long-term follow-up data in which the aspartame groups regained less weight than the control group. An effect of 0.2 SD corresponds to about a 3% reduction in bodyweight (2.3 kg for an adult weighing 75 kg). Given the weighted average study length was 12 weeks, this gives an estimated rate of weight loss of around 0.2 kg/week for a 75-kg adult. The meta-analyses demonstrate that using foods and drinks sweetened with aspartame instead of sucrose results in a significant reduction in both energy intakes and bodyweight. Meta-analyses both of energy intake and of weight loss produced an estimated rate of weight loss of about 0.2 kg/week. This close agreement between the figure calculated from reductions in energy intake and actual measures of weight loss gives confidence that this is a true effect. The two meta-analyses used different sets of studies with widely differing designs and controls. Although this makes comparisons between them difficult, it suggests that the final figure of around 0.2 kg/week is robust and is applicable to the variety of ways aspartame-containing foods are used by consumers. This review has shown that using foods and drinks sweetened with aspartame instead of those sweetened with sucrose is an effective way to maintain and lose weight without reducing the palatability of the diet. The decrease in energy intakes and the rate of weight loss that can reasonably be achieved is low but meaningful and, on a population basis, more than sufficient to counteract the current average rate of weight gain of around 0.007 kg/week. On an individual basis, it provides a useful adjunct to other weight loss regimes. Some compensation for the substituted energy does occur but this is only about one-third of the energy replaced and is probably less when using soft drinks sweetened with aspartame. Nevertheless, these compensation values are derived from short-term studies. More data are needed over the longer term to determine whether a tolerance to the effects is acquired. To achieve the average rate of weight loss seen in these studies of 0.2 kg/week will require around a 220-kcal (0.93 MJ) deficit per day based on an energy value for obese tissue of 7500 kcal/kg. Assuming the higher rate of compensation (32%), this would require the substitution of around 330 kcal/day (1.4 MJ/day) from sucrose with aspartame (which is equivalent to around 88 g of sucrose). Using the lower estimated rate of compensation for soft drinks alone (15.5%) would require the substitution of about 260 kcal/day (1.1 MJ/day) from sucrose with aspartame. This is equivalent to 70 g of sucrose or about two cans of soft drinks every day. [source] WHAT KIND OF PHILOSOPHER WAS LOCKE ON MIND AND BODY?PACIFIC PHILOSOPHICAL QUARTERLY, Issue 2 2010HAN-KYUL KIM The wide range of conflicting interpretations that exist in regard to Locke's philosophy of mind and body (i.e. dualistic, materialist, idealistic) can be explained by the general failure of commentators to appreciate the full extent of his nominalism. Although his nominalism that focuses on specific natural kinds has been much discussed, his mind-body nominalism remains largely neglected. This neglect, I shall argue, has given rise to the current diversity of interpretations. This paper offers a solution to this interpretative puzzle, and it attributes a view to Locke that I shall describe as nominal symmetry. [source] Changes in red cell ion transport, reduced intratumoral neovascularization, and some mild motor function abnormalities accompany targeted disruption of the Mouse Kell gene (Kel),AMERICAN JOURNAL OF HEMATOLOGY, Issue 8 2009Xiang Zhu Kell (ECE-3), a highly polymorphic blood group glycoprotein, displays more than 30 antigens that produce allo-antibodies and, on red blood cells (RBCs), is complexed through a single disulfide bond with the integral membrane protein, XK. XK is a putative membrane transporter whose absence results in a late onset form of neuromuscular abnormalities known as the McLeod syndrome. Although Kell glycoprotein is known to be an endothelin-3-converting enzyme, the full extent of its physiological function is unknown. To study the functions of Kell glycoprotein, we undertook targeted disruption of the murine Kel gene by homologous recombination. RBCs from Kel(,/,) mice lacked Kell glycoprotein, Kell/XK complex, and endothelin-3-converting enzyme activity and had reduced levels of XK. XK mRNA levels in spleen, brain, and testis were unchanged. In Kel(,/,) mice RBC Gardos channel activity was increased and the normal enhancement by endothelin-3 was blunted. Analysis of the microvessels of tumors produced from LL2 cells indicated that the central portion of tumors from wild-type mice were populated with many mature blood vessels, but that vessels in tumors from Kel(,/,) mice were fewer and smaller. The absence of Kell glycoprotein mildly affected some motor activities identified by foot splay on the drop tests. The targeted disruption of Kel in mouse enabled us to identify phenotypes that would not be easily detected in humans lacking Kell glycoprotein. In this regard, the Kell knockout mouse provides a good animal model for the study of normal and/or pathophysiological functions of Kell glycoprotein. Am. J. Hematol., 2009. © 2009 Wiley-Liss, Inc. [source] Computational chemistry study of the environmentally important acid-catalyzed hydrolysis of atrazine and related 2-chloro- s -triazinesPEST MANAGEMENT SCIENCE (FORMERLY: PESTICIDE SCIENCE), Issue 8 2002Phillip Sawunyama Abstract Many chlorine-containing pesticides, for example 2-chloro- s -triazines, are of great concern both environmentally and toxicologically. As a result, ascertaining or predicting the fate and transport of these compounds in soils and water is of current interest. Transformation pathways for 2-chloro- s -triazines in the environment include dealkylation, dechlorination (hydrolysis), and ring cleavage. This study explored the feasibility of using computational chemistry, specifically the hybrid density functional theory method, B3LYP, to predict hydrolysis trends of atrazine (2-chloro- N4 -ethyl- N6 -isopropyl-1,3,5-triazine-2,4-diamine) and related 2-chloro- s -triazines to the corresponding 2-hydroxy- s -triazines. Gas-phase energetics are described on the basis of calculations performed at the B3LYP/6-311++G(d,p)//B3LYP/6-31G* level of theory. Calculated free energies of hydrolysis (,hG298) are nearly the same for simazine (2-chloro- N4,N6 -diethyl-1,3,5-triazine-2,4-diamine), atrazine, and propazine (2-chloro- N4,N6 -di-isopropyl-1,3,5-triazine-2,4-diamine), suggesting that hydrolysis is not significantly affected by the side-chain amine-nitrogen alkyl substituents. High-energy barriers also suggest that the reactions are not likely to be observed in the gas phase. Aqueous solvation effects were examined by means of self-consistent reaction field methods (SCRF). Molecular structures were optimized at the B3LYP/6-31G* level using the Onsager model, and solvation energies were calculated at the B3LYP/6-311++G(d,p) level using the isodensity surface polarizable continuum model (IPCM). Although the extent of solvent stabilization was greater for cationic species than neutral ones, the full extent of solvation is underestimated, especially for the transition state structures. As a consequence, the calculated hydrolysis barrier for protonated atrazine is exaggerated compared with the experimentally determined one. Overall, the hydrolysis reactions follow a concerted nucleophilic aromatic substitution (SNAr) pathway. Published in 2002 for SCI by John Wiley & Sons, Ltd [source] Imaging of the Calf Vocal Fold With High-Frequency Ultrasound,THE LARYNGOSCOPE, Issue 10 2008Conor J. Walsh MSME Abstract Objectives/Hypothesis: High-frequency ultrasound imaging offers the potential for assisting in the diagnosis and treatment of vocal fold pathology if it allows aspects of vocal fold microstructure to be visualized noninvasively. The objective of this study was to assess the ability of high-frequency ultrasound to image vocal fold anatomy and injected biomaterials. Study Design: The vocal folds of two excised calf larynges were imaged ex vivo and compared with corresponding histological sections. Methods: High-frequency ultrasound imaging was performed under saline submersion using 40 and 50 MHz transducers, and corresponding cryostat cross-sections were stained with H&E, Trichome, and Verhoeff's Van Gieson stains. Results: The epithelial surface, lamina propria, and underlying muscle were easily identified with the high-frequency ultrasound as verified with histological sections representing each imaged region. The arytenoid cartilage vocal process can also be clearly distinguished from the surrounding tissue, as can the full extent of injected biomaterials within the superficial lamina propria. Useful ultrasound resolution was obtained to depths of at least 10 mm within the tissue with the 40 MHz transducer. Conclusions: This preliminary study demonstrates the capability of high-frequency ultrasound to image the layered anatomy of the calf vocal fold and to discern materials injected into the superficial lamina propria, indicating that this technology holds a strong potential for use in phonosurgery. [source] Electrocardiographic Body Surface Mapping: Potential Tool for the Detection of Transient Myocardial Ischemia in the 21st Century?ANNALS OF NONINVASIVE ELECTROCARDIOLOGY, Issue 2 2009Monique R. Robinson D.Phil Coronary artery disease (CAD) is one of the leading causes of cardiovascular mortality and morbidity worldwide. CAD presents as a wide spectrum of clinical disease from stable angina to ST segment elevation myocardial infarction. The 12-lead electrocardiogram (ECG) has been the main tool for the diagnosis of these events for almost a century but is limited in its diagnostic ability. For patients with suspected angina, the exercise tolerance test is often used to provoke and detect stress-induced ischemia but does not provide a definitive answer in a substantial proportion of patients. Body surface mapping (BSM) is a technique that samples multiple points around the thorax to provide a more comprehensive electrocardiographic data set than the conventional 12-lead ECG. Moreover, recent preliminary data demonstrate that BSM can detect and display transient regional myocardial ischemia in an intuitive fashion, employing subtraction color mapping, making it potentially valuable for diagnosing CAD causing transient regional ischemia. Research is ongoing to determine the full extent of its utility. [source] WHEN IS A SERVICE AN ESSENTIAL PUBLIC SERVICE?ANNALS OF PUBLIC AND COOPERATIVE ECONOMICS, Issue 4 2009Steven Van De Walle ABSTRACT,:,Citizens consider certain public (and private) services as essential services and therefore to be shielded from the full extent of market forces. Little is known about why some services are considered essential public services while other sometimes very similar services are not. In this article, we analyze public opinion using Eurobarometer data to test models exploring what factors determine whether citizens in 15 EU countries consider certain services as essential services and therefore to be provided to all. Despite the variety in public opinion, political orientations and geographic factors do little to explain why citizens have different opinions about the provision of public services. The article ends by outlining a research agenda for the further analysis of this underexplored research topic. [source] Decorrugation, edge detection, and modelling of total field magnetic observations from a historic town site, Yellowstone National Park, USAARCHAEOLOGICAL PROSPECTION, Issue 1 2010Steven D. Sheriff Abstract Cinnabar, Montana is a historic town site and railroad depot near the northern edge of Yellowstone National Park and was inhabited between 1883 and 1903. Remains of foundations and old photographs help determine the area of the town, but the south and east limits are unknown. We acquired total field magnetic intensity data to help determine the full extent of the town. Randomly distributed ferrous magnetic sources on the surface and typical noise associated with acquisition complicate the signal. To separate signal and noise we applied filtering and edge detection techniques common in the aeromagnetic industry to our data. Regional removal, decorrugation, upward continuation, and edge detection successfully separated signal and noise. Following filtering, we extracted two larger anomalies from the data set. For those two anomalies, we estimated the edges of their causative sources by calculating the maxima in the horizontal gradient of their anomalies and by inverse modelling those sources; both methods yield similar results. An archaeological test unit excavation within one of the anomalies clearly indicates the remains of buried domestic features, the foundation to a house or other building associated with the late nineteenth to early twentieth century use of Cinnabar. Thus the southeast extent of Cinnabar is greater than previously thought. The lack of surface indicators or adequate historic photography precluded the identification of this buried feature without the aid of the magnetic study. Copyright © 2009 John Wiley & Sons, Ltd. [source] What a difference copy number variation makesBIOESSAYS, Issue 4 2007Hildegard Kehrer-Sawatzki DNA copy number variation (CNV) represents a considerable source of human genetic diversity. Recently,1 a global map of copy number variation in the human genome has been drawn up which reveals not only the ubiquity but also the complexity of this type of variation. Thus, two human genomes may differ by more than 20 Mb and it is likely that the full extent of CNV still remains to be discovered. Nearly 3000 genes are associated with CNV. This high degree of variability with regard to gene copy number between two individuals challenges definitions of normality. Many CNVs are located in regions of complex genomic structure and this currently limits the extent to which these variants can be genotyped by using tagging SNPs. However, some CNVs are already amenable to genome-wide association studies so that their influence on human phenotypic diversity and disease susceptibility may soon be determined. BioEssays 29:311,313, 2007. © 2007 Wiley Periodicals, Inc. [source] Sex differences in the prevalence of human birth defects: A population-based study,BIRTH DEFECTS RESEARCH, Issue 5 2001Joseph M. Lary Background Sex differences in the prevalence of several human birth defects have often been reported in the literature, but the extent of sex differences for most birth defects is unknown. To determine the full extent of sex differences in birth defects in a population, we examined population-based data from the Metropolitan Atlanta Congenital Defects Program (MACDP). Methods MACDP records were analyzed for 1968 through 1995. We determined the sex-specific prevalence of all major birth defects, using the total number of live births by sex during these years as the denominator. For each specific defect, we calculated a relative risk with regard to sex on the basis of the ratio of prevalence among males to prevalence among females. Male,female relative risks were also determined for total major birth defects and for several broad categories of defects. Results The overall prevalence of major defects at birth was 3.9% among males and 2.8% among females. All but two of the major categories of birth defects (nervous system defects and endocrine system defects) had a higher prevalence among males. Defects of the sex organs were eight and one-half times more prevalent among males and accounted for about half of the increased risk of birth defects among males relative to females. Urinary tract defects were 62% more prevalent among males, and gastrointestinal tract defects were 55% more prevalent among males. Among specific defect types, twofold or greater differences in prevalence by sex were common. Conclusions Our data indicate that sex differences in the prevalence of specific human birth defects are common, and male infants are at greater risk for birth defects than female infants. Several mechanisms have been proposed to account for these differences. Teratology 64:237,251, 2001. Published 2001 Wiley-Liss, Inc. [source] | ||||||||||||||||||||||