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Generating
Kinds of Generating Terms modified by Generating Selected AbstractsGenerating multiply charged protein ions via two-step electrospray ionization mass spectrometryJOURNAL OF MASS SPECTROMETRY (INCORP BIOLOGICAL MASS SPECTROMETRY), Issue 1 2002Chia-Cheng Lee [source] ChemInform Abstract: Alkynes as Equivalents of ,-Diazo Ketones in Generating ,-Oxo Metal Carbenes: A Gold-Catalyzed Expedient Synthesis of Dihydrofuran-3-ones.CHEMINFORM, Issue 31 2010Longwu Ye Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a "Full Text" option. The original article is trackable via the "References" option. [source] ChemInform Abstract: (NH4)2Te2WO8: A New Polar Oxide with Second-Harmonic Generating, Ferroelectric, and Pyroelectric Properties.CHEMINFORM, Issue 5 2008Jun-Ho Kim Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a "Full Text" option. The original article is trackable via the "References" option. [source] Vibration signals from the FT joint can induce phase transitions in both directions in motoneuron pools of the stick insect walking systemDEVELOPMENTAL NEUROBIOLOGY, Issue 2 2003Ulrich Bässler Abstract The influence of vibratory signals from the femoral chordotonal organ fCO on the activities of muscles and motoneurons in the three main leg joints of the stick insect leg, i.e., the thoraco,coxal (TC) joint, the coxa,trochanteral (CT) joint, and the femur,tibia (FT) joint, was investigated when the animal was in the active behavioral state. Vibration stimuli induced a switch in motor activity (phase transition), for example, in the FT joint motor activity switched from flexor tibiae to extensor tibiae or vice versa. Similarly, fCO vibration induced phase transitions in both directions between the motoneuron pools of the TC joint and the CT joint. There was no correlation between the directions of phase transition in different joints. Vibration stimuli presented during simultaneous fCO elongation terminated the reflex reversal motor pattern in the FT joint prematurely by activating extensor and inactivating flexor tibiae motoneurons. In legs with freely moving tibia, fCO vibration promoted phase transitions in tibial movement. Furthermore, ground vibration promoted stance,swing transitions as long as the leg was not close to its anterior extreme position during stepping. Our results provide evidence that, in the active behavioral state of the stick insect, vibration signals can access the rhythm generating or bistable networks of the three main leg joints and can promote phase transitions in motor activity in both directions. The results substantiate earlier findings on the modular structure of the single-leg walking pattern generator and indicate a new mechanism of how sensory influence can contribute to the synchronization of phase transitions in adjacent leg joints independent of the walking direction. © 2003 Wiley Periodicals, Inc. J Neurobiol 56: 125,138, 2003 [source] Postradical vaginal trachelectomy follow-up by isthmic-vaginal smear cytology: A 13-year auditDIAGNOSTIC CYTOPATHOLOGY, Issue 9 2009Zeina Ghorab M.D. Abstract Radical trachelectomy is a fertility preserving alternative for early cervical cancer patients. This audit assesses the role of isthmic-vaginal smear in postoperative follow-up. A total of 94 patients were identified generating 913 smears. The final surgical margin was at the lower uterine segment in 37 cases (39.4%) and significantly correlated with the presence of lower uterine segment endometrial cells (LUSEC) in smears (P = 0.035). The most common abnormal diagnoses in the presence of LUSEC were ASC-US and AGUS seen in 14.2% and 11.9% of positive smears, respectively. The most common follow-up pattern was initial positive smears, which converted to negative (45.7% of patients), showing that reactive changes are another potential overcall pitfall. The only 2 central recurrences were successfully diagnosed by smears. This study summarizes our experience, emphasizing the role of isthmic-vaginal smears for early detection of central recurrence and highlighting the role of LUSEC and reactive changes as potential overcall pitfalls. Diagn. Cytopathol. 2009. © 2009 Wiley-Liss, Inc. [source] Dual-asymmetry electrokinetic flow focusing for pre-concentration and analysis of catecholamines in CE electrochemical nanochannelsELECTROPHORESIS, Issue 14 2009Ren-Guei Wu Abstract In this research, a technique incorporating dual-asymmetry electrokinetic flow (DAEKF) was applied to a nanoCE electrochemical device for the pre-concentration and detection of catecholamines. The DAEKF was constructed by first generating a ,-potential difference between the top and bottom walls, which had been pre-treated with O2 and H2O surface plasma, respectively, yielding a 2-D gradient shear flow across the channel depth. The shear flow was then exposed to a varying ,-potential along the downstream direction by control of the field-effect in order to cause downward rotational flow in the channel. By this mechanism, almost all of the samples were effectively brought down to the electrode surface for analysis. Simulations were carried out to reveal the mechanism of concentration caused by the DAEKF, and the results reasonably describe our experiment findings. This DAEKF technique was applied to a glass/glass CE electrochemical nanochip for the analysis of catecholamines. The optimum detection limit was determined to be 1.25 and 3.3,nM of dopamine and catechol, respectively. A detection limit at the zeptomole level for dopamine can be obtained in this device, which is close to the level released by a single neuron cell in vitro. [source] Gravity-induced convective flow in microfluidic systems: Electrochemical characterization and application to enzyme-linked immunosorbent assay testsELECTROPHORESIS, Issue 21-22 2004Patrick Morier Abstract A way of using gravity flow to induce a linear convection within a microfluidic system is presented. It is shown and mathematically supported that tilting a 1 cm long covered microchannel is enough to generate flow rates up to 1000 nL·min -1, which represents a linear velocity of 2.4 mm·s -1. This paper also presents a method to monitor the microfluidic events occurring in a covered microchannel when a difference of pressure is applied to force a solution to flow in said covered microchannel, thanks to electrodes inserted in the microfluidic device. Gravity-induced flow monitored electrochemically is applied to the performance of a parallel-microchannel enzyme-linked immunosorbent assay (ELISA) of the thyroid-stimulating hormone (TSH) with electrochemical detection. A simple method for generating and monitoring fluid flows is described, which can, for instance, be used for controlling parallel assays in microsystems. [source] A statistical method for scanning the genome for regions with rare disease allelesGENETIC EPIDEMIOLOGY, Issue 5 2010Chad GarnerArticle first published online: 21 JUN 2010 Abstract Studying the role of rare alleles in common disease has been prevented by the impractical task of determining the DNA sequence of large numbers of individuals. Next-generation DNA sequencing technologies are being developed that will make it possible for genetic studies of common disease to study the full frequency spectrum of genetic variation, including rare alleles. This report describes a method for scanning the genome for disease susceptibility regions that show an increased number of rare alleles among a sample of disease cases versus an ethnically matched sample of controls. The method was based on a hidden Markov model and the statistical support for a disease susceptibility region characterized by rare alleles was measured by a likelihood ratio statistic. Due to the lack of empirical data, the method was evaluated through simulation. The performance of the method was tested under the null and alternative hypotheses under a range of sequence generating and hidden Markov models parameters. The results showed that the statistical method performs well at identifying true disease susceptibility regions and that performance was primarily affected by the amount of variation in the neutral sequence and the number of rare disease alleles found in the disease susceptibility region. Genet. Epidemiol. 34: 386,395, 2010. © 2010 Wiley-Liss, Inc. [source] Power of the Rank Adjacency Statistic to Detect Spatial Clustering in a Small Number of RegionsGEOGRAPHICAL ANALYSIS, Issue 1 2001John Paul Ekwaru The rank adjacency statistic D is a statistical method for assessing spatial autocorrelation or clustering of geographical data. It was originally proposed for summarizing the geographical patterns of cancer data in Scotland (IARC 1985). In this paper, we investigate the power of the rank adjacency statistic to detect spatial clustering when a small number of regions is involved. The investigations were carried out using Monte Carlo simulations, which involved generating patterned/clustered values and computing the power with which the D statistic would detect it. To investigate the effects of region shapes, structure of the regions, and definition of weights, simulations were carried out using two different region shapes, binary and nonhinary weights, and three different lattice structures. The results indicate that in the typical example of considering Canadian total mortality at the electoral district level, the D statistic had adequate power to detect general spatial autocorrelation in twenty-five or more regions. There was an inverse relationship between power and the level of connectedness of the regions, which depends on the weighting function, shape, and arrangement of the regions. The power of the D statistic was also found to compare favorably with that of Moran's I statistic. [source] Impact of nutrition support on treatment outcome in patients with locally advanced head and neck squamous cell cancer treated with definitive radiotherapy: A secondary analysis of RTOG trial 90-03,HEAD & NECK: JOURNAL FOR THE SCIENCES & SPECIALTIES OF THE HEAD AND NECK, Issue 4 2006Rachel Rabinovitch MD Abstract Background. The aim was to evaluate the relationship between nutrition support (NS) on host toxicity and cancer outcome in patients with locally advanced head and neck squamous cell carcinoma (HNSCC) undergoing definitive radiotherapy (XRT). Methods. We performed a secondary analysis of Radiation Therapy Oncology Group (RTOG) 90-03, a prospective randomized trial evaluating four definitive XRT fractionation schedules in patients with locally advanced HNSCC, which prospectively collected data on NS delivered before treatment (BNS), during treatment (TNS), and after definitive XRT. NS data and pretreatment characteristics of the 1073 evaluable patients were analyzed against therapy toxicity and outcome. Results. Patients receiving BNS experienced significantly less weight loss by the end of treatment and less grade 3 to 4 mucositis than patients not receiving BNS. However, patients receiving BNS had a poorer 5-year actuarial locoregional control rate than patients receiving TNS or no NS (29%, 55%, and 57%, respectively, p < .0001) and a poorer 5-year overall survival rate (16%, 36%, and 49%, respectively, p < .0001). Patients receiving BNS were significantly more likely to have a higher T classification, N status, and overall American Joint Committee on Cancer (AJCC) stage and initial presentation with greater pretreatment weight loss, and a poorer Karnofsky Performance Status (KPS) than patients not receiving BNS. After adjusting for the impact of these prognostic factors through a recursive partition analysis, a multivariate analysis with a stratified Cox model found that BNS was still a highly significant independent prognostic factor for increased locoregional failure (hazards ratio [HR], 1.47; 95% confidence interval [CI], 1.21,1.79; p < .0001) and death (HR, 1.41; 95% CI, 1.19,1.67; p < .0001). Conclusion. In this study, the largest prospective evaluation of nutrition data in treated patients with cancer, BNS was associated with inferior treatment outcome in the patients with HNSCC undergoing XRT. These results should be considered hypothesis generating and encourage prospective clinical research and identification of the mechanisms underlying this finding. © 2005 Wiley Periodicals, Inc. Head Neck28: 287,296, 2006 [source] Evaluation of operators' performance for automation design in the fully digital control room of nuclear power plantsHUMAN FACTORS AND ERGONOMICS IN MANUFACTURING & SERVICE INDUSTRIES, Issue 1 2010Chiuhsiang Joe Lin Abstract Recent technical developments in computer hardware and software have meant that human,machine systems can be automated in many respects. If automation fails, however, human operators can have difficulty in recognizing the existence of a problem, identifying what has failed, and taking corrective action to remedy these out-of-the-loop (OOTL) performance problems. Several studies have suggested that taxonomies of levels of automation (LOAs) and types of automation (TOAs) can be used to solve OOTL problems. This study examined the impact of LOAs in process control automation within the context of nuclear power plants (NPPs). A simulation experiment in an NPP is performed to validate this framework using an automatic mode and a semiautomatic mode. Mental demand is found to be significantly reduced under the automatic mode; however, participants felt frustrated with this LOA. Situation awareness is found to be similar in the two modes. The results of an end-of-experiment subjective rating reveal that participants were evenly divided between the two modes with respect to generating and selecting functions. It is therefore suggested that human operators be involved in generating and selecting functions under an automatic mode. © 2009 Wiley Periodicals, Inc. [source] The Multiple Roles of Additives in CaCO3 Crystallization: A Quantitative Case StudyADVANCED MATERIALS, Issue 4 2009Denis Gebauer To date, the knowledge of the multiple roles of additives in calcium carbonate crystallization results from empirical control of crystal growth. We present a crystallization assay generating controlled supersaturation, which allows the categorization of different modes of additive action. This facilitates a novel understanding of the action of crystallization additives. [source] "I think of God, in order not to be aware": defensive dissociation and the use of religious objectsINTERNATIONAL JOURNAL OF APPLIED PSYCHOANALYTIC STUDIES, Issue 2 2004Ryan LaMothe Associate Professor of Pastoral Counselling Abstract This article explores the relation between defensive dissociation and the use of religious objects from three related directions. First, religious objects and their attributes provide an interpretative framework that generates, for the believer, an unassailable and thoroughly self-consistent experience of agentic hate and hostility and a concomitant sense of worth, power, and efficacy, which together keep intolerable anxiety unformulated and thus outside of awareness. The unassailable religious object (e.g., crucifix or swastika) points to the collapse of potential space whereby doubt and ambiguity, which are necessary for the construction of new meaning, are eliminated. Second, I depict how unthinkable anxiety is dissociated, in part, through the formulation of omnipotent identifications and these identifications represent a collapse of potential space , a refusal to recognize likeness in difference and difference in likeness. Third, the collapse of potential space attends the breakdown of the dynamic tension between generating and submitting to experience. On the one hand, this collapse enables a compulsive, omnipotent construction of experience, a concomitant rigid subjectivity, and the foreclosure of new meaning. On the other hand, it leads to an intrapsychic, desymbolized space: an empty space from which subjectivity, meaning, and value are absent. The hidden presence of desymbolized space is indicated in the intentional construction of a depersonalized other and by the wish or plan to annihilate real and imagined others. Copyright © 2004 Whurr Publishers Ltd. [source] The Impact of Generating Initial Hypothesis Sets of Different Sizes on the Quality of the Initial Set, and the Resulting Time Efficiency and Final Judgment AccuracyINTERNATIONAL JOURNAL OF AUDITING, Issue 1 2004Sudip Bhattacharjee This study examines the impact of generating initial hypothesis sets of different sizes on the quality of the hypotheses generated (i.e., the ability to consider both the direction and accounts that are over- or understated). We also examine the time efficiency, information search effectiveness, and the final judgment accuracy, conditional on the quality of the initial hypothesis set. Sixty auditors performed an analytical procedures task where they were asked to generate and test either a specific number of initial hypotheses (one, three, or six), or any number of hypotheses desired in order to uncover an error seeded in the financial statements. The results indicate that the three hypotheses group initially generated hypotheses of the highest quality and maintained the hypothesis quality after efficiently searching information and generating additional causes. The one hypothesis group improved the quality of their hypotheses only after generating and testing several causes. However, auditors who generated six hypotheses or any number desired (as in audit practice) considered hypotheses of lower quality in the initial set, and did not improve the hypotheses quality after going through the information search stage. These results suggest that the size of the initial hypothesis set can lead to differences in the gains that accrue from the hypothesis generation and information search stages of diagnostic decisions. [source] The MUC1 oncoprotein as a functional target: Immunotoxin binding to ,/, junction mediates cell killingINTERNATIONAL JOURNAL OF CANCER, Issue 1 2009Daniel B. Rubinstein Abstract MUC1, a heavily glycosylated mucin, has generated considerable interest as a target for tumor killing because of its overexpression in malignancies. Full-length MUC1 (MUC1/TM) is proteolytically cleaved after synthesis generating , and , subunits, which specifically bind in a noncovalent interaction. Although the , chain remains on the cell surface, the , chain binds in an on-and-off interaction. Most anti-MUC1 antibodies (Abs) described to date recognize epitopes within the highly immunogenic ,-chain tandem repeat. Because the ,-chain is shed, such Abs are sequestered and fail to reach MUC1-expressing cells. Immunizing with cDNA encoding MUC1/TM and the spliced MUC1/X isoform from which the tandem repeat has been deleted yielded antibodies to the MUC1 ,/, junction. Pseudomonas toxin PE38 linked to polyclonal anti-MUC1 ,/, junction Abs both bound and killed MUC1-positive malignant cells. Monoclonal DMC209 binds the MUC1 ,/, junction in both MUC1/X and MUC1/TM. When injected into SCID mice xenotransplanted with human breast cancer MDA-MB-231, monoclonal DMC209 showed significant in vivo tumor-suppressive activity. The MUC1/X ,/, junction presents a biologically-significant target in MUC1-expressing malignancies because (i) antibodies directed against cell-bound ,/, junction epitopes reach the intended cellular target, (ii) antibodies to junction epitope are internalized into cells, (iii) anti ,/, junction antibodies can effectively kill high MUC1-expressing cancer cells as antibody-toxin conjugates and (iv) antibodies targeting the MUC1 cell-bound ,/, junction results in tumor suppression in vivo. Our results indicate that cell-bound MUC1 ,/, junction, unlike shed alpha chain, represents a highly effective moiety for targeting and killing MUC1-expressing malignancies. © 2008 Wiley-Liss, Inc. [source] Understanding heterogeneity in meta-analysis: the role of meta-regressionINTERNATIONAL JOURNAL OF CLINICAL PRACTICE, Issue 10 2009W. L. Baker Summary Background:, Meta-regression has grown in popularity in recent years, paralleling the increasing numbers of systematic reviews and meta-analysis published in the biomedical literature. However, many clinicians and decision-makers may be unfamiliar with the underlying principles and assumptions made within meta-regression leading to incorrect interpretation of their results. Aims:, This paper reviews the appropriate use and interpretation of meta-regression in the medical literature, including cautions and caveats to its use. Materials & Methods:, A literature search of MEDLINE (OVID) from 1966-February 2009 was conducted to identify literature relevant to the topic of heterogeneity and/or meta-regression in systematic reviews and meta-analysis. Results:, Meta-analysis, a statistical method of pooling data from studies included in a systematic review, is often compromised by heterogeneity of its results. This could include clinical, methodological or statistical heterogeneity. Meta-regression, said to be a merging of meta-analytic and linear regression principles, is a more sophisticated tool for exploring heterogeneity. It aims to discern whether a linear relationship exists between an outcome measure and on or more covariates. The associations found in a meta-regression should be considered hypothesis generating and not regarded as proof of causality. Conclusions:, The current review will enable clinicians and healthcare decision-makers to appropriately interpret the results of meta-regression when used within the constructs of a systematic review, and be able to extend it to their clinical practice. [source] Influence of the surface on thrombin generationINTERNATIONAL JOURNAL OF LABORATORY HEMATOLOGY, Issue 4 2008T. W. STIEF Summary Thrombin generation depends on the surface of the blood vessel or container. With a new ultra-sensitive and -specific thrombin assay the surface-dependent thrombin generation was quantified. Citrated blood or plasma was preincubated for 1 h (37 °C). Citrated blood, plasma, or plasma with 0,10 g/l hemoglobin,erythrocyte microparticles (Hb,MP) were preincubated at 23 °C or at 37 °C. Plasma samples (50 ,l) were recalcified in polystyrol (PS) wells and incubated for different coagulation reaction times (CRT). Final supramolar arginine concentrations, 0.1% Triton X 100, and chromogenic thrombin substrate concentrations in the onefold km,range were added and the linear ,A/t was measured in the recalcified coagulation activity assay (RECA). Aprotinin or corn trypsin inhibitor were added. (i) Recalcification of plasma (in different monovettes) pre-incubated for 1 h (37 °C) generated the following thrombin activities after 7 min (37 °C): 0.74 IU/ml (polypropylene (PP)-citrate), 0.39 IU/ml (PP-EDTA), 0.06 IU/ml (PP-heparin), 1.38 IU/ml (PS), 0.63 IU/ml (1 ml volume PP), 0.13 IU/ml (15 ml volume PP), and 3.62 IU/ml (glass). (ii) Recalcification of preincubated whole blood generated up to about fivefold more thrombin. (iii) Thrombin generation is proportional to the plasmatic concentration of Hb,MP, 10 g/l Hb,MP generating about 4 IU/ml thrombin within 20 min CRT. (iv) The IC50 of aprotinin and corn typsin inhibitor on thrombin generation in RECA are about 2 KIU/ml and about 1 U/ml, respectively. The reaction wall, the preincubation temperature, and hemolysis influences thrombin generation. The RECA allows to diagnose the prothrombotic capacity of any material. [source] An enhanced Markov chain based model for the narrowband LMS channel in built-up areasINTERNATIONAL JOURNAL OF SATELLITE COMMUNICATIONS AND NETWORKING, Issue 2 2005F. Perez-Fontán Abstract In this paper, a technique to derive the transition probabilities for a Markov chain model for the land mobile satellite (LMS) channel in built-up areas is presented. This technique contributes to improving empirically derived parameters in that it can account for elevation and street orientation effects as well as building density. Physical-statistical or ,virtual city' techniques are used to relate observed edification statistics to signal attenuation statistics. This methodology can also be applied to generating correlated time-series for simultaneous links to a constellation of satellites from the same mobile terminal. The proposed approach also allows the generation of enhanced time-series which take into account diffuse multipath and diffraction effects. Copyright © 2005 John Wiley & Sons, Ltd. [source] RNase P RNA-mediated cleavageIUBMB LIFE, Issue 3 2009Leif A. Kirsebom Abstract Metal(II)-induced hydrolysis of RNA produce products with 5,-hydroxyls and 2,;3,-cyclic phosphates at the ends. Ribozymes are RNA molecules that act as catalysts. Some ribozymes that cleave RNA also generate 5,-hydroxyls and 2,;3,-cyclic phosphates whereas others produces 5,-phosphates and 3,-hydroxyls at the ends of the cleavage products. RNase P is an essential endoribonuclease involved in RNA processing. The catalytic RNA subunit of RNase P is a trans-acting ribozyme that cleaves various RNA substrates in vitro generating 5,-phosphates and 3,-hydroxyls as cleavage products. The activity depends on the presence of metal(II) ions such as Mg2+. RNase P RNA has therefore to facilitate a nucleophilic attack that generates the correct product ends and prevent metal(II)-induced hydrolysis of the RNA substrate. In this review, we will discuss our current understanding of the interactions between RNase P RNA and its substrate, role of specific residues with respect to catalysis and positioning of functionally important Mg2+ at and in the vicinity of the cleavage site that ensures that products with correct ends are generated. Moreover, we will discuss the composition of RNase P and its RNA subunit in an evolutionary perspective. © 2009 IUBMB IUBMB Life, 61(3):189,200, 2009 [source] East meets west: adaptive evolution of an insect introduced for biological controlJOURNAL OF APPLIED ECOLOGY, Issue 3 2008C. B Phillips Summary 1A possible explanation for low success rates when introducing natural enemies to new regions for biological control of insect pests is that they fail to adapt to their new conditions. Therefore it has been widely recommended that biological control practitioners increase the probability of local adaptation by maximizing the genetic variation released. An alternative recommendation is to use climate matching to identify native populations that may already possess traits suited to the new region. However, support for these recommendations is weak through lack of empirical evidence that local adaptation is important to biological control. 2This study examined how genetic drift and selection influenced the population frequencies of two asexually reproducing, genetically differentiated parasitoid biotypes that were introduced to New Zealand from South America for biological control. Other than by mutation, the biotypes were genetically fixed due to the absence of recombination both within and between biotypes. This meant that adaptive evolution could occur only if selection acted on any traits that varied between the biotypes introduced from South America. 3The two parasitoid biotypes were released simultaneously at 14 sites and their frequencies were monitored for up to 10 years. Changes in biotype frequency were consistent with strong directional selection favouring one of the South American biotypes, thus generating established parasitoid populations that were better adapted to New Zealand conditions than those that had originally been released. This local adaptation of the control agent contributed to greater mortality of the pest. 4Synthesis and applications. This study provides the first clear demonstration of the importance of releasing natural enemy genetic variation in new regions to foster adaptive evolution and improve success rates in classical biological control. However, the benefit to biological control of maximizing the genetic variation released needs to be balanced against possible risks to non-target species. The results do not support the concept of choosing sampling sites for putative biological control agents based solely on climatic similarities between the source location and the intended region of introduction. [source] Bayesian counterfactual analysis of the sources of the great moderationJOURNAL OF APPLIED ECONOMETRICS, Issue 2 2008Chang-Jin Kim We use counterfactual experiments to investigate the sources of the large volatility reduction in US real GDP growth in the 1980s. Contrary to an existing literature that conducts counterfactual experiments based on classical estimation and point estimates, we consider Bayesian analysis that provides a straightforward measure of estimation uncertainty for the counterfactual quantity of interest. Using Blanchard and Quah's (1989) structural VAR model of output growth and the unemployment rate, we find strong statistical support for the idea that a counterfactual change in the size of structural shocks alone, with no corresponding change in the propagation of these shocks, would have produced the same overall volatility reduction as what actually occurred. Looking deeper, we find evidence that a counterfactual change in the size of aggregate supply shocks alone would have generated a larger volatility reduction than a counterfactual change in the size of aggregate demand shocks alone. We show that these results are consistent with a standard monetary VAR, for which counterfactual analysis also suggests the importance of shocks in generating the volatility reduction, but with the counterfactual change in monetary shocks alone generating a small reduction in volatility. Copyright © 2007 John Wiley & Sons, Ltd. [source] Distribution modelling and statistical phylogeography: an integrative framework for generating and testing alternative biogeographical hypothesesJOURNAL OF BIOGEOGRAPHY, Issue 11 2007Corinne L. Richards Abstract Statistical phylogeographic studies contribute to our understanding of the factors that influence population divergence and speciation, and that ultimately generate biogeographical patterns. The use of coalescent modelling for analyses of genetic data provides a framework for statistically testing alternative hypotheses about the timing and pattern of divergence. However, the extent to which such approaches contribute to our understanding of biogeography depends on how well the alternative hypotheses chosen capture relevant aspects of species histories. New modelling techniques, which explicitly incorporate spatio-geographic data external to the gene trees themselves, provide a means for generating realistic phylogeographic hypotheses, even for taxa without a detailed fossil record. Here we illustrate how two such techniques , species distribution modelling and its historical extension, palaeodistribution modelling , in conjunction with coalescent simulations can be used to generate and test alternative hypotheses. In doing so, we highlight a few key studies that have creatively integrated both historical geographic and genetic data and argue for the wider incorporation of such explicit integrations in biogeographical studies. [source] Impairment of cytoskeleton-dependent vesicle and organelle translocation in green algae: combined use of a microfocused infrared laser as microbeam and optical tweezersJOURNAL OF MICROSCOPY, Issue 2 2002A. Holzinger Summary A Nd-YAG laser at 1064 nm is used as optical tweezers to move intracellular objects and a laser microbeam to cause impairment of cytoskeleton tracks and influence intracellular motions in desmidiaceaen green algae. Naturally occurring migrations of large nuclei are inhibited in Micrasterias denticulata and Pleurenterium tumidum when the responsible microtubules are targeted with a laser microbeam generating 180 mW power in the focal plane. Impairment of the microtubule tracks appears to be irreversible, as the nucleus cannot pass the former irradiated area in Pleurenterium or remains abnormally dislocated in Micrasterias. The actin filament-dependent movement of secretory vesicles and smaller particles can be manipulated by the same IR-laser at 90 mW when functioning as optical tweezers. In Closterium lunula particles are displaced from their cytoplasmic tracks for up to 10 µm but return to their tracks immediately after removing the light pressure gained by the optical tweezers. The cytoplasmic tracks consist of actin filament cables running parallel to the longitudinal axis of Closterium cells as depicted by Alexa phalloidin staining and confocal laser scanning microscopy. Dynamics and extensibility of the cytoplasmic strands connecting particles to the tracks are also demonstrated in the area of large vacuoles which are surrounded by actin filament bundles. In Micrasterias trapping of secretory vesicles by the optical tweezers causes irreversible malformations of the cell shape. The vesicle accumulation itself dissipates within 30 s after removing the optical tweezers, also indicating reversibility of the effects induced, in the case of actin filament-mediated processes. [source] Poster Sessions CP10: Blood,Brain BarrierJOURNAL OF NEUROCHEMISTRY, Issue 2002M. A. García Kinetic analysis of vitamin C uptake has demonstrated that specialized cells take up ascorbic acid (AA), the reduced form of vitamin C, through sodium-AA cotransporters. Recently, two different isoforms of sodium-vitamin C cotransporters (SVCT 1, 2) that mediate high affinity Na+ -dependent l -ascorbic acid have been cloned. SVCT2 was detected mainly in choroid plexus cells and neurons, however, there are no evidences of SVCT2 expression in glial cells. High concentrations of vitamin C has been demonstrated in brain hypothalamic area. The hypothalamic glial cells, known as alpha and beta tanycytes, are specialized ependymal cells that bridge the cerebrospinal fluid and the portal blood of the median eminence. Our hypothesis postulates that tanycytes take up reduced vitamin C from the portal blood and cerebrospinal fluid generating an high concentration of this vitamin in brain hypothalamic area. In situ immunohistochemical analyses demonstrated that SVCT2 transporter is selectively expressed in apical region of tanycytes. A newly developed primary culture of mouse hypothalamic tanycytes was used to confirm the expression and function of SVCT2 isoform in these cells. Reduced vitamin C uptake was temperature and sodium dependent. Kinetic analysis showed an apparent Km of 20 ,m and a Vmax of 45 pmol/min per million cells for the transport of ascorbic acid. The expression of SVCT2 was confirmed by immunoblots and RT,PCR. Tanycytes may perform a neuroprotective role concentrating the vitamin C in the hypothalamic area. Acknowledgements:, Supported by Grands FONDECYT 1010843 and DIUC-GIA 201.034.006-1.4 from Concepción University. [source] Association Between Val66Met Brain-Derived Neurotrophic Factor (BDNF) Gene Polymorphism and Post-Treatment Relapse in Alcohol DependenceALCOHOLISM, Issue 4 2009Marcin Wojnar Background:, The purpose of this study was to examine relationships between genetic markers of central serotonin (5-HT) and dopamine function, and risk for post-treatment relapse, in a sample of alcohol-dependent patients. Methods:, The study included 154 patients from addiction treatment programs in Poland, who met DSM-IV criteria for alcohol dependence. After assessing demographics, severity of alcohol use, suicidality, impulsivity, depression, hopelessness, and severity of alcohol use at baseline, patients were followed for approximately 1 year to evaluate treatment outcomes. Genetic polymorphisms in several genes (TPH2, SLC6A4, HTR1A, HTR2A, COMT, and BDNF) were tested as predictors of relapse (defined as any drinking during follow-up) while controlling for baseline measures. Results:, Of 154 eligible patients, 123 (80%) completed follow-up and 48% (n = 59) of these individuals relapsed. Patients with the Val allele in the Val66Met BDNF polymorphism and the Met allele in the Val158Met COMT polymorphism were more likely to relapse. Only the BDNF Val/Val genotype predicted post-treatment relapse [odds ratio (OR) = 2.62; p = 0.019], and time to relapse (OR = 2.57; p = 0.002), after adjusting for baseline measures and other significant genetic markers. When the analysis was restricted to patients with a family history of alcohol dependence (n = 73), the associations between the BDNF Val/Val genotype and relapse (OR = 5.76, p = 0.0045) and time to relapse (hazard ratio = 4.93, p = 0.001) were even stronger. Conclusions:, The Val66Met BDNF gene polymorphism was associated with a higher risk and earlier occurrence of relapse among patients treated for alcohol dependence. The study suggests a relationship between genetic markers and treatment outcomes in alcohol dependence. Because a large number of statistical tests were conducted for this study and the literature on genetics and relapse is so novel, the results should be considered as hypothesis generating and need to be replicated in independent studies. [source] Solubilisation of proteins from rayfish residues by endogenous and commercial enzymesJOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE, Issue 1 2004Laura Pastoriza Abstract The aim of the present study was to design methods for the digestion of fish proteins from processing wastes, leading to new possibilities for little-used species or those generating a significant volume of residues. Residues of rayfish (Raja clavata) were used for the solubilisation of protein by hydrolysis treatment. The kinetics of hydrolysis was studied using rayfish enzymes, either by autolysis of the protein in a triturate of the raw material or by application of a multi-enzyme preparation previously extracted from the viscera of the species. Their effectiveness was compared with that of two commercial enzymes, papain and pepsin. Optimum conditions of hydrolysis and enzymatic activity for digestion with rayfish enzymes were ascertained. The yield of material and the efficiency of digestion in each of the hydrolysis processes are reported. Copyright © 2003 Society of Chemical Industry [source] Variation in 24 hemostatic genes and associations with non-fatal myocardial infarction and ischemic strokeJOURNAL OF THROMBOSIS AND HAEMOSTASIS, Issue 1 2008N. L. SMITH Summary., Background:, Arterial thrombosis involves platelet aggregation and clot formation, yet little is known about the contribution of genetic variation in fibrin-based hemostatic factors to arterial clotting risk. We hypothesized that common variation in 24 coagulation,fibrinolysis genes would contribute to risk of incident myocardial infarction (MI) or ischemic stroke (IS). Methods:, We conducted a population-based, case,control study. Subjects were hypertensive adults and postmenopausal women 30,79 years of age, who sustained a first MI (n = 856) or IS (n = 368) between 1995 and 2002, and controls matched on age, hypertension status, and calendar year (n = 2689). We investigated the risk of MI and IS associated with (i) global variation within each gene as measured by common haplotypes and (ii) individual haplotypes and single nucleotide polymorphisms (SNPs). Significance was assessed using a 0.2 threshold of the false discovery rate q -value, which accounts for multiple testing. Results:, After accounting for multiple testing, global genetic variation in factor (F) VIII was associated with IS risk. Two haplotypes in FVIII and one in FXIIIa1 were significantly associated with increased IS risk (all q -values < 0.2). A plasminogen gene SNP was associated with MI risk. All are new discoveries not previously reported. Another 24 tests had P -values < 0.05 and q -values > 0.2 in MI and IS analyses, 23 of which are new and hypothesis generating. Conclusions:, Apart from the association of FVIII variation with IS, we found little evidence that common variation in the 24 candidate fibrin-based hemostasis genes strongly influences arterial thrombotic risk, but our results cannot rule out small effects. [source] Repetition rate continuously controllable passively Q-switched Nd:YAG bonded microchip laserLASER PHYSICS LETTERS, Issue 8 2007H. Lei Abstract A stable repetition rate continuously controllable passively Q-switched Nd:YAG bonded microchip laser is presented. A 0.8 mm-thickness 7 mm-diameter Nd:YAG crystal at 1.6 at.% is adapted as active medium and the saturable absorber for passively Q-switched pulse generating, a 0.2 mm-thickness 6.8-mm diameter Cr4+:YAG piece was thermal bonded into the Nd:YAG after primary optical contact. By using pulse pump and controlling the duty cycle of electric pulse and temperature of laser diode, a 1 W C-mount packaged fast-collimated laser diode, we can continuously achieve repetition rate from 1 kHz to 10 kHz as active Q-switched laser. The delay time at 10 kHz is 90 ,s, while the single pulse energy is 2.8 ,J with pulse width of 2 ns. (© 2007 by Astro Ltd., Published exclusively by WILEY-VCH Verlag GmbH & Co. KGaA) [source] Is the prevalence of asthma declining?ALLERGY, Issue 2 2010Systematic review of epidemiological studies To cite this article: Anandan C, Nurmatov U, van Schayck OCP, Sheikh A. Is the prevalence of asthma declining? Systematic review of epidemiological studies. Allergy 2010; 65: 152,167. Abstract Asthma prevalence has increased very considerably in recent decades such that it is now one of the commonest chronic disorders in the world. Recent evidence from epidemiological studies, however, suggests that the prevalence of asthma may now be declining in many parts of the world, which, if true is important for health service planning and also because this offers the possibility of generating and testing new aetiological hypotheses. Our objective was to determine whether the prevalence of asthma is declining worldwide. We undertook a systematic search of EMBASE, Medline, Web of Science and Google Scholar, for high quality reports of cohort studies, repeat cross-sectional studies and analyses of routine healthcare datasets to examine international trends in asthma prevalence in children and adults for the period 1990,2008. There were 48 full reports of studies that satisfied our inclusion criteria. The large volume of data identified clearly indicate that there are, at present, no overall signs of a declining trend in asthma prevalence; on the contrary, asthma prevalence is in many parts of the world still increasing. The reductions in emergency healthcare utilization being reported in some economically developed countries most probably reflect improvements in quality of care. There remain major gaps in the literature on asthma trends in relation to Africa and parts of Asia. There is no overall global downward trend in the prevalence of asthma. Healthcare planners will for the foreseeable future, therefore, need to continue with high levels of anticipated expenditure in relation to provision of asthma care. [source] Bases, spanning sets, and the axiom of choiceMLQ- MATHEMATICAL LOGIC QUARTERLY, Issue 3 2007Paul Howard Abstract Two theorems are proved: First that the statement "there exists a field F such that for every vector space over F, every generating set contains a basis" implies the axiom of choice. This generalizes theorems of Halpern, Blass, and Keremedis. Secondly, we prove that the assertion that every vector space over ,2 has a basis implies that every well-ordered collection of two-element sets has a choice function. (© 2007 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] | |||||||||||||||||||||||||||||||||||||||||||