Dramatic Increase (dramatic + increase)

Distribution by Scientific Domains
Distribution within Medical Sciences


Selected Abstracts


Disrupting the Master Narrative: Global Politics, Historical Memory, and the Implications for Naturalization Education

ANTHROPOLOGY & EDUCATION QUARTERLY, Issue 1 2010
Daryl M. Gordon
Dramatic increases in immigration pose challenges for democratic citizenship education to involve national members with different historical memories and current experiences of national belonging. The article draws on ethnographic research with Laotian refugees, who were the target of U.S. violence during the Vietnam War and later became naturalized U.S. citizens. The author contrasts the narrative of citizenship that informs naturalization education with complex ideologies of citizenship articulated by refugees. She argues that a nuanced understanding of citizenship can lead to more meaningful naturalization education, which is necessary to produce citizens with a full sense of national membership and agency in the democratic process.,[naturalization, national belonging, citizenship education, refugees] [source]


Asymmetric localization of numb in the chick somite and the influence of myogenic signals

DEVELOPMENTAL DYNAMICS, Issue 3 2006
Tamara Holowacz
Abstract Whereas Notch signaling is known to play an essential role in the formation of somites, its role during later stages of somite maturation is less well understood. Here, we examine the signals and transcription factors that control the expression of the Notch antagonist, Numb, during somite maturation in the chick embryo. Numb mRNA is present in the epithelial somite and is increased in expression in the forming myotome. Numb protein displays a very specific subcellular localization and dynamic expression during somite maturation. Numb protein is asymmetrically localized in a cortical crescent on the basal side of dividing cells in the dorsomedial lip of the dermomyotome and is subsequently uniformly distributed throughout differentiated myotomal cells. Treatment of somites with either the combination of Wnt-3a and Shh, or ectodermal signals plus noggin, both of which induce somitic myogenesis, did not significantly affect Numb transcript levels but did lead to a dramatic increase in the levels of Numb protein, which was uniformly distributed throughout the cytoplasm of the resultant myotubes. Forced expression of MyoD in somites similarly induced high levels of Numb protein throughout the cytoplasm, without affecting Numb mRNA levels. We also found that signals that promote somitic myogenesis or forced MyoD expression induced expression of the Notch ligand, Serrate-2. Our findings suggest that Notch signals are specifically repressed in the myotome and that asymmetric expression of Numb in dividing cells of the dorsomedial lip of the dermomyotome may modulate whether these cells continue to divide or differentiate into myotomal cells. Developmental Dynamics 235:633,645, 2006. © 2006 Wiley-Liss, Inc. [source]


Brief exposure to the biological mother "potentiates" the isolation behavior of precocial Guinea pig pups

DEVELOPMENTAL PSYCHOBIOLOGY, Issue 8 2006
Michael B. Hennessy
Abstract When isolated rat pups are briefly reunited with a lactating female, her subsequent removal leads to a dramatic increase in the emission of ultrasonic vocalizations, but not other behaviors. Whether this socially induced augmentation of isolation behavior (i.e., "potentiation") is characteristic only of altricial rodents is not known. Therefore, we examined precocial guinea pig pups in a potentiation paradigm. Ten-day-old guinea pigs were isolated in a test cage for 10 min, at which time they were then placed into a second cage for 5 min that either contained a companion or, for controls, was empty. Pups were then isolated again in the test cage for a second 10-min period. Control pups showed a significant reduction in vocalizing and locomotor activity from the first to second isolation period. Exposure to the biological mother prevented the decline in both behaviors (Experiment 1), whereas exposure to a familiar littermate (Experiment 2) had no effect, and exposure to an unfamiliar lactating female (Experiment 3) had only a minimal effect on locomotor activity. The results show that potentiation of isolation behaviors is not limited to altricial rodents, and suggest that specific characteristics of the effect (i.e., its magnitude, the specific behaviors affected, and the selectivity of the response to particular social partners) varies with the abilities and requirements of the young, as well as the behavioral ecology of the species in question. © 2006 Wiley Periodicals, Inc. Dev Psychobiol 48: 653,659, 2006. [source]


Diabetes management in the new millennium using insulin pump therapy

DIABETES/METABOLISM: RESEARCH AND REVIEWS, Issue S1 2002
Bruce W. Bode
Abstract Current goals of therapy of type 1 and 2 diabetes are to achieve near normal glycemia, minimize the risk of severe hypoglycemia, limit excessive weight gain, improve quality of life and delay or prevent late vascular complications. As discussed in this review, insulin pump or continuous subcutaneous insulin infusion (CSII) therapy provides a treatment option that can dramatically aid in achieving all of these goals. In comparison to multiple daily injections (MDI), CSII uses only rapid-acting insulin, provides greater flexibility in timing of meals and snacks, has programmable basal rates to optimize overnight glycemic control, can reduce the risk of exercise-induced hypoglycemia, and enhances patients' ability to control their own diabetes. Most important, in adults and adolescents with type 1 diabetes, CSII has been shown to lower HbA1c levels, reduce the frequency of severe hypoglycemia and limit excessive weight gain versus MDI without increasing the risk of diabetic ketoacidosis. Similarly positive results are being seen with CSII in adults with type 2 diabetes. The effectiveness of CSII and improvements in pump technology have fueled a dramatic increase in the use of this therapy. Practical guidelines are presented for selection of patients, initiation of treatment, patient education, follow-up assessments and troubleshooting. The recent introduction of methods for continuous glucose monitoring provides a new means to optimize the basal and bolus capabilities of CSII and offers the hope of the development of a feedback-controlled artificial pancreas. Copyright © 2002 John Wiley & Sons, Ltd. [source]


Surge in treatment admissions related to methamphetamine use in Cape Town, South Africa: implications for public health

DRUG AND ALCOHOL REVIEW, Issue 2 2008
ANDREAS PLÜDDEMANN
Abstract Introduction and Aims. In the past decade, methamphetamine has become increasingly a drug of concern globally. The purpose of this study is to describe the changing trends in treatment admissions for methamphetamine abuse in Cape Town, South Africa and to highlight the implications of these changes for policy, practice and research. Design and Methods. Data were collected on admissions for drug abuse treatment through a regular monitoring system involving drug treatment centres and programmes in Cape Town every 6 months as part of the South African Community Epidemiology Network on Drug Use (SACENDU). A one-page form was completed by treatment centre personnel to obtain demographic data, the patients' primary and secondary substances of abuse, the mode, frequency and age of first use of substance and information on prior treatment. Results. The results indicate that between 2004 and 2006 a dramatic increase in treatment admissions for methamphetamine abuse occurred, a large proportion of the methamphetamine patients are adolescents and that the drug is almost exclusively smoked. Discussion and Conclusions. The rapid increase in admissions for methamphetamine abuse is of great concern, particularly as the drug has a number of serious, often chronic, side effects and that a large proportion of the patients are adolescents. The implications for public health are discussed. [source]


Novel Anion Exchangers for Electrodes with Improved Selectivity to Divalent Anions

ELECTROANALYSIS, Issue 17 2004
Vladimir Egorov
Abstract It has been found that replacing of several long-chain alkyl substituents at the nitrogen atom of lipophilic quaternary ammonium salts (QAS) by methyls results in a dramatic increase of the potentiometric selectivity of ion-selective electrodes (ISE) with QAS-based plasticized PVC membranes to some divalent anions against the monovalent ones. The discussed effect of QAS cation nature on the potentiometric selectivity is also partly retained for ISE with neutral carrier-based membranes doped with QAS to provide anion permselectivity. This opens up new possibilities to control the potentiometric selectivity of ISE for divalent anions by the appropriate selection of the anion exchanger. [source]


2-D difference gel electrophoresis of the lung squamous cell carcinoma versus normal sera demonstrates consistent alterations in the levels of ten specific proteins

ELECTROPHORESIS, Issue 23 2007
Paul Dowling Dr.
Abstract Most lung cancers are diagnosed too late for curative treatment to be possible, therefore early detection is crucial. Serum proteins are a rich source of biomarkers and have the potential to be used as diagnostic and prognostic indicators for lung cancer. In order to examine differences in serum levels of specific proteins associated with human lung squamous carcinoma, immunodepletion of albumin and five other high-abundant serum proteins followed by 2-D difference gel electrophoresis (DIGE) analysis and subsequent MS was used to generate a panel of proteins found to be differentially expressed between the cancer and normal samples. Proteins found to have increased abundance levels in squamous cell carcinoma sera compared to normal sera included apolipoprotein A-IV precursor, chain F; human complement component C3c, haptoglobin, serum amyloid A protein precursor and Ras-related protein Rab-7b. Proteins found to have lower abundance levels in squamous cell carcinoma sera compared to normal sera included alpha-2-HS glycoprotein, hemopexin precursor, proapolipoprotein, antithrombin III and SP40; 40. The data presented here demonstrate that high-abundant protein removal combined with 2-D DIGE is a powerful strategy for the discovery of potential biomarkers. The identification of lung cancer-specific biomarkers is crucial to early detection, which in turn could lead to a dramatic increase in survival rates. [source]


Highly sensitive and simple fluorescence staining of proteins in sodium dodecyl sulfate-polyacrylamide-based gels by using hydrophobic tail-mediated enhancement of fluorescein luminescence

ELECTROPHORESIS, Issue 19-20 2003
Chulhun Kang
Abstract Fluorescein has an extremely low luminescence intensity in acidic aqueous media. However, when it was bound to proteins, subsequent increase of luminescence intensity took place. Furthermore, when a hydrophobic tail, such as aliphatic hydrocarbons, was introduced to fluorescein, more dramatic increase of luminescence intensity was observed upon binding to proteins. In the present study, by utilizing this luminescence enhancement, three hydrophobic fluorescein dyes (5-dodecanoyl amino fluorescein, 5-hexadecanoyl amino fluorescein, and 5-octadecanoyl amino fluorescein) were examined as noncovalent fluorescent stains of protein bands in sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). Effective incorporation of the dyes to proteins in gels was accomplished either simply by adding dyes at the protein fixation step, or by treating gels with a staining solution after the fixation. The sensitivity of this staining method using the fluorescein derivatives was approximately 1 ng/band for most proteins. For some cases, protein bands containing as low as 0.1 ng were successfully visualized. In addition, the detection sensitivity showed much less protein-to-protein variation than silver staining. This new staining method was also successfully applied to two-dimensional electrophoresis of rat brain proteins. Its overall sensitivity was comparable to that of silver staining. [source]


Key role of selective viral-induced mortality in determining marine bacterial community composition

ENVIRONMENTAL MICROBIOLOGY, Issue 2 2007
T. Bouvier
Summary Viral infection is thought to play an important role in shaping bacterial community composition and diversity in aquatic ecosystems, but the strength of this interaction and the mechanisms underlying this regulation are still not well understood. The consensus is that viruses may impact the dominant bacterial strains, but there is little information as to how viruses may affect the less abundant taxa, which often comprise the bulk of the total bacterial diversity. The potential effect of viruses on the phylogenetic composition of marine bacterioplankton was assessed by incubating marine bacteria collected along a North Pacific coastal-open ocean transect in seawater that was greatly depleted of ambient viruses. The ambient communities were dominated by typical marine groups, including alphaproteobacteria and the Bacteroidetes. Incubation of these communities in virus-depleted ambient water yielded an unexpected and dramatic increase in the relative abundance of bacterial groups that are generally undetectable in the in situ assemblages, such as betaproteobacteria and Actinobacteria. Our results suggest that host susceptibility is not necessarily only proportional to its density but to other characteristics of the host, that rare marine bacterial groups may be more susceptible to viral-induced mortality, and that these rare groups may actually be the winners of competition for resources. These observations are not inconsistent with the ,phage kills the winner' hypothesis but represent an extreme and yet undocumented case of this paradigm, where the potential winners apparently never actually develop beyond a very low abundance threshold in situ. We further suggest that this mode of regulation may influence not just the distribution of single strains but of entire phylogenetic groups. [source]


Inhibition of Notch signaling biases rat thymocyte development towards the NK cell lineage

EUROPEAN JOURNAL OF IMMUNOLOGY, Issue 5 2004
Jens van den Brandt
Abstract Notch receptors are involved in directing the choice between alternative cell fates in developmental scenarios such as thymopoiesis. By pharmacological interference in rat fetal thymus organ culture we show that inhibition of Notch signaling arrests T,cell development at an early double-negative stage and is accompanied by a dramatic increase in the number of NK cells. These cells show an activated phenotype, lack recombination of the TCR, gene locus and express perforin. Similarly, in thymic lobes reconstituted with fetal liver cells, progenitors predominantly develop into NK cells both after pharmacological interference of Notch and after treatment with a recombinant rat Notch1/Fc chimera. Collectively, this identifies the lineage decision of NK/T precursor cells as an important site of Notch action in rat thymocytes. [source]


CLINICAL STUDY: Suppression of cue-induced heroin craving and cue-reactivity by single-trial transcutaneous electrical nerve stimulation at 2 Hz

ADDICTION BIOLOGY, Issue 2 2006
Fei Zhong
ABSTRACT The purpose of the present study was to investigate the efficacy of 2 Hz transcutaneous electrical nerve stimulation (TENS) to reduce cue-induced heroin craving and the corresponding cardiovascular responses. Seventy heroin addicts with at least 1 month of abstinence were enrolled and randomly divided into two groups of 35, to receive single-trial 2 Hz TENS (TENS group) or mock TENS (mock group) during experimental procedure, respectively. They were required to express their degree of craving by visual analog scale before and after the presentation of a video-cue, and after TENS treatment, which lasted for 30 minutes. Heart rate and arterial blood pressure were simultaneously monitored in 56 cases, with 28 in each group. Results show that in mock group, video-cue induced a dramatic increase of craving score, which did not return to baseline in 150 minutes, whereas in the TENS group, 2 Hz TENS treatment produced a significant decrease of craving, reaching baseline in 90 minutes. Video-cue induced a significant increase of heart rate and systolic and diastolic blood pressure, which remained elevated for at least 60 minutes in the mock group; whereas in the TENS group, they returned to baseline immediately after the termination of TENS. These results indicate that the craving induced by a heroin-related cue can be immediately and significantly suppressed, and the cardiovascular activation totally abolished by a single-trial 2 Hz TENS for 30 minutes [source]


Forced swim stress activates rat hippocampal serotonergic neurotransmission involving a corticotropin-releasing hormone receptor-dependent mechanism

EUROPEAN JOURNAL OF NEUROSCIENCE, Issue 12 2002
Astrid C. E. Linthorst
Summary Serotonin is important for adequate coping with stress. Aberrant serotonin function is implicated in the aetiology of major depression and anxiety disorders. Dysregulation of the hypothalamic,pituitary,adrenocortical axis, involving elevated corticotropin-releasing hormone (CRH) activity, also plays a role in these stress-related illnesses. Here we studied the effects of stress on hippocampal serotonin and the role of the CRH system using in vivo microdialysis. First, rats were subjected to a forced swim stress, resulting in a dramatic increase in hippocampal serotonin (1500% of baseline), which was associated with the occurrence of diving behaviour. The diving-associated increase in serotonin depended on activation of CRH receptors, as it was antagonized by intracerebroventricular pretreatment with D -Phe-CRH12,41. Secondly, the effects of intracerebroventricular administration of CRH and urocortin (0.03,1.0 µg) were studied. Both CRH and urocortin caused a dose-dependent rise in hippocampal serotonin (maximally 350% of baseline) and 5-hydroxyindoleacetic acid levels, suggesting the involvement of CRH receptor type 1. Because the effects of urocortin were prolonged, CRH receptor type 2 could play a role in a later phase of the neurotransmitter response. Experiments using adrenalectomized rats showed that CRH-induced serotonin changes were adrenally independent. These data suggest that the raphe-hippocampal serotonin system is able to mount, CRH receptor-dependent, responses to specific stressful situations that surpass the usually observed maximal increases of about 300% of baseline during stress and enhanced vigilance. [source]


Redistribution of small GTP-binding protein, Rab27B, in rat parotid acinar cells after stimulation with isoproterenol

EUROPEAN JOURNAL OF ORAL SCIENCES, Issue 3 2009
Akane Imai
Small GTP-binding protein, Rab27, has been implicated in the regulation of different types of membrane trafficking, including melanosome transport in melanocytes and regulated secretion events in a wide variety of secretory cells. We have previously shown that Rab27 is involved in the control of isoproterenol (IPR)-induced amylase release from rat parotid acinar cells. Although Rab27 is predominantly localized on secretory granules under resting conditions, changes to its intracellular localization after ,-stimulation have never been elucidated. The present study investigated IPR-induced redistribution of Rab27B in the parotid acinar cells, revealing translocation from secretory granules to the subapical region after 5 min of IPR treatment and then diffusion into the cytosol after 30 min of IPR treatment. Dissociation of Rab27B from the apical plasma membrane is probably mediated through the Rab GDP dissociation inhibitor (GDI) in the cytosol extracting GDP-bound Rab protein from membranes, as a dramatic increase in the amount of the Rab27B,GDI complex in the cytosol was observed 30 min after stimulation with IPR. These results indicate that, in parotid acinar cells, Rab27B is translocated, in a time-dependent manner, from secretory granules into the apical plasma membrane as a result of exposure to IPR, and then into the cytosol through binding with the GDI. [source]


Heparin-binding hemagglutinin (HBHA) of Mycobacterium leprae is expressed during infection and enhances bacterial adherence to epithelial cells

FEMS MICROBIOLOGY LETTERS, Issue 2 2009
Cristiana Soares De Lima
Abstract A heparin-binding hemagglutinin (HBHA) expressed on the surface of Mycobacterium tuberculosis is an antigenic protein that has been implicated in bacterial adherence to epithelial cells and systemic dissemination. In this study, the potential role of the Mycobacterium leprae HBHA (ML-HBHA) homologue in leprosy was investigated. Initially, the in vivo expression of HBHA and its association with the M. leprae cell envelope was confirmed by immunoblotting and proteomic analysis. Mycobacterium leprae recombinant HBHA (rML-HBHA) bound to a heparin,Sepharose column, and its capacity to act as an adhesin was demonstrated in experiments showing that the exogenous addition of the protein to latex beads or to M. leprae cells promotes a dramatic increase in association with epithelial cells. Finally, serum anti-HBHA immunoglobulin G levels were investigated in individuals infected with M. leprae. Altogether, our data indicate that HBHA is recognized during the course of bacterial infection in humans and may play a role in leprosy pathogenesis. [source]


The effect of temperature and ventilation condition on the toxic product yields from burning polymers

FIRE AND MATERIALS, Issue 1 2008
A. A. Stec
Abstract A major cause of death or permanent injury in fires is inhalation of toxic gases. Moreover, every fire is unique, and the range of products, highly dependant on fire conditions, produces a wide variety of toxic and irritant species responsible for the most fire fatalities. Therefore, to fully understand each contribution to the toxicity it is necessary to quantify the decomposition products of the material under the test. Fires can be divided into a number of stages from smouldering combustion to early well-ventilated flaming through to fully developed under-ventilated flaming. These stages can be replicated by certain bench-scale physical fire models using different fuel-to-oxygen ratios, controlled by the primary air flow, and expressed in terms of the equivalence ratio (the actual fuel/air ratio divided by the stoichiometric fuel/air ratio). This work presents combustion product yields generated using a small-scale fire model. The Purser Furnace apparatus (BS7990 and ISO TS 19700) enables different fire stages to be created. Identification and quantification of combustion gases and particularly their toxic components from different fire scenarios were undertaken by continuous Fourier transform infrared spectroscopy. The relationship between type of the fire particularly the temperature and ventilation conditions and the toxic product yields for four bulk polymers, low-density polyethylene, polystyrene (PS), Nylon 6.6 and polyvinyl chloride (PVC) is reported. For all the polymers tested, except PVC, there is a dramatic increase in the yield of products of incomplete combustion (CO and hydrocarbons) with increase in equivalence ratio, as might be expected. For PVC there is a consistently high level of products of incomplete combustion arising both from flame inhibition by HCl and oxygen depletion. There is a low sensitivity to furnace temperature over the range 650,850°C, except that at 650°C PS shows an unexpectedly high yield of CO under well-ventilated conditions and PVC shows a slightly higher hydrocarbon yield. This demonstrates the dependence of toxic product yields on the equivalence ratio, and the lack of dependence on furnace temperature, within this range. Copyright © 2007 John Wiley & Sons, Ltd. [source]


Two hundred years of a diverse Daphnia community in Lake Naivasha (Kenya): effects of natural and human-induced environmental changes

FRESHWATER BIOLOGY, Issue 8 2004
Joachim Mergeay
Summary 1. We used fossil diapausing eggs extracted from 210Pb-dated sediment cores to reconstruct historical changes in the Daphnia community of Lake Naivasha, a climate-sensitive lake in Kenya which over the past 200 years has experienced a series of well-documented natural and anthropogenic environmental changes. 2. Contiguous sampling and analysis of four cores yielded ephippial capsules of eight Daphnia species. Only two of these had been recorded previously in live collections from Lake Naivasha, and one species is new to science. The four more common species (Daphnia barbata, D. laevis, D. magna, and D. pulex) show striking differences in abundance patterns and population dynamics through time. Four other species (D. lumholtzi, D. curvirostris, D. longispina s.l., and Daphnia sp. nov. type Limuru.) appear to have been present only occasionally. Nevertheless, between 1895 and 1915 seven species of Daphnia inhabited Lake Naivasha simultaneously. 3. Despite considerable natural environmental change associated with climate-driven lake-level fluctuations, the Daphnia community of Lake Naivasha has been severely affected by human activities over the past century, especially the introduction of exotic fishes and water-quality changes because of agricultural soil erosion. The recent reappearance of large-bodied Daphnia species (D. magna, D. barbata, D. lumholtzi, Daphnia sp. nov. type Limuru) after 20,110 years of absence can be explained by their release from fish predation, following a dramatic increase in turbidity caused by excess clastic sediment input from eroded catchment soils. The small-bodied species D. laevis has fared less well recently, presumably because the benefit of lowered predation pressure is counteracted by more pronounced negative effects of increased turbidity on this species and loss of submerged macrophyte beds which formerly served as predation refuge. 4. Our results suggest that, despite considerable environmental instability and the absence of specialised zooplanktivores, top-down control of fish on large zooplankton is important in Lake Naivasha. Predation pressure from fish has led to clear-cut shifts in local Daphnia species composition, but failed to drive the larger taxa to extinction. [source]


The mechanisms of resistance to antimalarial drugs in Plasmodium falciparum

FUNDAMENTAL & CLINICAL PHARMACOLOGY, Issue 2 2003
Jacques Le Bras
Abstract Drug-resistant malaria is primarily caused by Plasmodium falciparum, a species highly prevalent in tropical Africa, the Amazon region and South-east Asia. It causes severe fever or anaemia that leads to more than a million deaths each year. The emergence of chloroquine resistance has been associated with a dramatic increase in malaria mortality among inhabitants of some endemic regions. The rationale for chemoprophylaxis is weakening as multiple-drug resistance develops against well-tolerated drugs. Plasmodium falciparum drug-resistant malaria originates from chromosome mutations. Analysis by molecular, genetic and biochemical approaches has shown that (i) impaired chloroquine uptake by the parasite vacuole is a common characteristic of resistant strains, and this phenotype is correlated with mutations of the Pfmdr1, Pfcg2 and Pfcrt genes; (ii) one to four point mutations of dihydrofolate reductase (DHFR), the enzyme target of antifolates (pyrimethamine and proguanil) produce a moderate to high level of resistance to these drugs; (iii) the mechanism of resistance to sulfonamides and sulfones involves mutations of dihydropteroate synthase (DHPS), their enzyme target; (iv) treatment with sulphadoxine,pyrimethamine selects for DHFR variants Ile(51), Arg(59), and Asn(108) and for DHPS variants Ser(436), Gly(437), and Glu(540); (v) clones that were resistant to some traditional antimalarial agents acquire resistance to new ones at a high frequency (accelerated resistance to multiple drugs, ARMD). The mechanisms of resistance for amino-alcohols (quinine, mefloquine and halofantrine) are still unclear. Epidemiological studies have established that the frequency of chloroquine resistant mutants varies among isolated parasite populations, while resistance to antifolates is highly prevalent in most malarial endemic countries. Established and strong drug pressure combined with low antiparasitic immunity probably explains the multidrug-resistance encountered in the forests of South-east Asia and South America. In Africa, frequent genetic recombinations in Plasmodium originate from a high level of malaria transmission, and falciparum chloroquine-resistant prevalence seems to stabilize at the same level as chloroquine-sensitive malaria. Nevertheless, resistance levels may differ according to place and time. In vivo and in vitro tests do not provide an adequate accurate map of resistance. Biochemical tools at a low cost are urgently needed for prospective monitoring of resistance. [source]


The Care,tech Link: An Examination of Gender, Care and Technical Work in Healthcare Labour

GENDER, WORK & ORGANISATION, Issue 4 2008
Sally Lindsay
Despite the dramatic increase of technology in the healthcare field, little is known of how care work and technical work are related. Examining substitute healthcare providers offers a useful illustration of the care,tech link because nursing (care) and medical (technical) models often merge. Forty-two interviews with men and women (nurse practitioners, nurse anaesthetists and physician assistants) were conducted in the USA. The results showed that the gendered nature of care,tech boundaries has shifted in small but important ways and that the gendering of work influenced the shape of these boundaries. Men often encountered barriers when moving too far into the care realm and attempted to overcome this by ,caring cautiously' and emphasizing problem-solving care. Women faced similar barriers from the ,old boys network' when they entered highly technical areas. There is also evidence that men and women challenged existing care,tech boundaries and moved beyond their traditional roles. [source]


Selective elimination of amplified CDK4 sequences correlates with spontaneous adipocytic differentiation in liposarcoma

GENES, CHROMOSOMES AND CANCER, Issue 11 2009
Zofia Hélias-Rodzewicz
Well-differentiated and undifferentiated liposarcomas are characterized by high-level amplifications of chromosome 12 regions including the CDK4 and MDM2 genes. These amplicons are either localized, in well-differentiated liposarcoma (WDLPS), on extrachromosomal structures (ring or rod chromosomes), or integrated into chromosome arms in undifferentiated tumors. Our results reveal that extrachromosomal amplicons are unstable, and frequently lost by micronucleation. This loss correlates with hypermethylation of eliminated sequences and changes of their replication time. Treatment of cells with demethylating agents during early S-phase significantly decreases the rate of micronuclei positive for CDK4. We also demonstrate that, in our model, micronuclei are generated during anaphase as a consequence of anaphase abnormalities (chromosome lagging and anaphase bridges). Finally, a dramatic increase of adipocytic differentiation was noted in cells that have eliminated copies of CDK4 gene in micronuclei. These findings provide evidence that, in WDLPS, adipocytic differentiation could be the consequence of CDK4 loss, an event occurring rarely in undifferentiated tumors in which the amplified sequences are integrated into chromosome arms. © 2009 Wiley-Liss, Inc. [source]


Noninvasive diagnosis and monitoring of nonalcoholic steatohepatitis: Present and future,

HEPATOLOGY, Issue 2 2007
Anna Wieckowska
Nonalcoholic fatty liver disease (NAFLD) is the most common chronic liver disease in the United States, and its prevalence is increasing worldwide. It currently affects approximately 30% of adults and 10% of children in the United States. NAFLD represents a wide spectrum of conditions ranging from simple fatty liver which in general follows a benign nonprogressive clinical course, to nonalcoholic steatohepatitis (NASH), which is a more serious form of NAFLD that may progress to cirrhosis and end-stage liver disease. At present, a liver biopsy remains the only reliable way to diagnose NASH and establish the presence of fibrosis. Current noninvasive clinically available tests lack accuracy and reliability. In light of the dramatic increase in the prevalence of NAFLD in conjunction with the significant research effort in developing novel therapies for patients with NASH, noninvasive, simple, reproducible, and reliable biomarkers are greatly needed. They will not only help in the diagnosis of NASH, but also be useful for assessment of treatment response and prognosis and remain a research priority in the NAFLD field. (HEPATOLOGY 2007;46:582,589.) [source]


Novel PlexorÔ SNP genotyping technology: comparisons with TaqMan® and homogenous MassEXTENDÔ MALDI-TOF mass spectrometry,

HUMAN MUTATION, Issue 9 2007
E.A. Tindall
Abstract Analysis of SNPs for association, linkage, haplotype, and pharmacogenetic studies has led to a dramatic increase in the number and evolution of medium- to high-throughput genotyping technologies. This study introduces PlexorÔ as a new method for medium-throughput (single SNP) genotyping. We compare this fluorescent-based chemistry for call rate, accuracy, affordability, throughput, and overall efficiency against two commonly used technologies. These include fluorescent-based TaqMan® allelic discrimination for single SNP analysis (medium-throughput) and the homogenous MassEXTENDÔ (hMEÔ) chemistry using matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF) mass spectrometry for multiple SNP analysis (high-throughput). Analysis of 11 SNPs, including all six possible nucleotide substitutions, showed PlexorÔ to be highly comparable for both call rate (94.7%) and accuracy (99.2%) to the TaqMan® (94.6% and 99.8%, respectively) and hMEÔ (91.9% and 98.1%, respectively) chemistries. We demonstrate that this novel method is an efficient, cost-effective alternative to TaqMan® genotyping commonly used in diagnostic settings. Hum Mutat 28(9), 922,927, 2007. © 2007 Wiley-Liss, Inc. [source]


Changes in clutch size, brood size and numbers of nesting Squacco Herons Ardeola ralloides over a 32-year period in the Camargue, southern France

IBIS, Issue 1 2001
HEINZ HAFNER
Changes in numbers of nesting pairs, clutch size, and brood size of Squacco Herons Ardeola ralloides in the Camargue, southern France were analysed over a 32-year period. The annual numbers of breeding pairs [average 84 pairs pL 30 sd, n = 32 years) exhibited a possible increasing trend, but with considerable variability. This variability is associated with local spring rainfall, which may influence the available surface area of their preferred freshwater habitats. In contrast to population size, clutch size decreased substantially in recent years. Our data do not provide a causal explanation for this change in clutch size, although the reduction temporally corresponds with increasing rice cultivation and with a dramatic increase in the number of Cattle Egrets Bubulcus ibis in the Camargue. [source]


A multimodel assessment of future climatological droughts in the United Kingdom,

INTERNATIONAL JOURNAL OF CLIMATOLOGY, Issue 14 2009
Jean-Philippe Vidal
Abstract This paper presents a detailed assessment of future rainfall drought patterns over the United Kingdom. Previously developed bias-corrected high-resolution gridded precipitation time series are aggregated to the scale relevant for water resources management, in order to provide 21st-century time series for 183 hydrologic areas, as computed by six General Circulation Models (GCMs) under two emissions scenarios. The control run data are used as a ,learning time series' to compute the Standardized Precipitation Index (SPI) at four different time scales. SPI values for three 30-year future time slices are computed with respect to these learning time series in order to assess the changes in drought frequency. Multimodel results under the A2 scenario show a dramatic increase in the frequency of short-term extreme drought class for most of the country. A decrease of long-term droughts is expected in Scotland, due to the projected increase in winter precipitation. The analysis for two catchment case studies also showed that changes under the B2 scenario are generally consistent with those of the A2 scenario, with a reduced magnitude in changes. The overall increase with time in the spread of individual GCM results demonstrates the utility of multimodel statistics when assessing the uncertainty in future drought indices to be used in long-term water resources planning. Copyright © 2009 Royal Meteorological Society [source]


Online end-to-end quality of service monitoring for service level agreement management

INTERNATIONAL JOURNAL OF COMMUNICATION SYSTEMS, Issue 4 2008
Xiaoyuan Ta
Abstract A major challenge in network and service level agreement (SLA) management is to provide Quality of Service (QoS) demanded by heterogeneous network applications. Online QoS monitoring plays an important role in the process by providing objective measurements that can be used for improving network design, troubleshooting and management. Online QoS monitoring becomes increasingly difficult and complex due to the rapid expansion of the Internet and the dramatic increase in the speed of network. Sampling techniques have been explored as a means to reduce the difficulty and complexity of measurement. In this paper, we investigate several major sampling techniques, i.e. systematic sampling, simple random sampling and stratified sampling. Performance analysis is conducted on these techniques. It is shown that stratified sampling with optimum allocation has the best performance. However, stratified sampling with optimum allocation requires additional statistics usually not available for real-time applications. An adaptive stratified sampling algorithm is proposed to solve the problem. Both theoretical analysis and simulation show that the proposed adaptive stratified sampling algorithm outperforms other sampling techniques and achieves a performance comparable to stratified sampling with optimum allocation. A QoS monitoring software using the aforementioned sampling techniques is designed and tested in various real networks. Copyright © 2007 John Wiley & Sons, Ltd. [source]


Changing concepts of bladder regeneration

INTERNATIONAL JOURNAL OF UROLOGY, Issue 8 2007
Akihiro Kanematsu
Abstract: During the last decade, there has been a dramatic increase in studies aimed at regeneration of the urinary bladder. Many studies employed animal-derived or synthetic materials as grafts for experimental bladder augmentation models, with or without additional measures to promote regeneration, such as autologous cell transplantation or growth factor loading. However, in spite of encouraging results in several reports, few methodologies have shown proven definitive clinical utility. One major problem in these studies is the lack of a clear distinction between native and regenerated bladder in total bladder function after augmentation. Another crucial problem is the absorption and shrinkage of larger grafts, which may result from insufficient vascular supply and smooth muscle regeneration. In contrast, researchers have recently attempted to establish alternative regenerative strategies for treating bladder diseases, and have employed far more diverse approaches according to the various pathological conditions to be treated. For total replacement of the bladder after cystectomy for invasive bladder cancer, urothelium-covered neobladder with non-urinary tract backbone remains a viable choice. In addition, functional bladder diseases such as urinary incontinence, weak detrusor, or non-compliant fibrotic bladder have also been major targets for many leading research groups in this field. These conditions are studied much more from different therapeutic standpoints, aiming at the prevention or reversal of pathological conditions in muscle remodeling or neural control. Such altered research direction would inevitably lead to less surgically based basic biological research, and also would include a far wider spectrum of adult and pediatric bladder diseases, from overactive bladder to dysfunctional voiding. [source]


Fifty Years of Refugee Studies: From Theory to Policy

INTERNATIONAL MIGRATION REVIEW, Issue 1 2001
Richard Black
This article reviews the growth of the field of refugee studies, focusing on its links with, and impact on, refugee policy. The last fifty years, and especially the last two decades, have witnessed both a dramatic increase in academic work on refugees and significant institutional development in the field. It is argued that these institutions have developed strong links with policymakers, although this has often failed to translate into significant policy impacts. Areas in which future policy-orientated work might be developed are considered. [source]


GAAP versus The Street: An Empirical Assessment of Two Alternative Definitions of Earnings

JOURNAL OF ACCOUNTING RESEARCH, Issue 1 2002
Mark T. Bradshaw
Managers, security analysts, investors, and the press rely increasingly on modified definitions of GAAP net income, known by such names as "operating" and "pro forma" earnings. We document this phenomenon and discuss competing explanations for the recent rise in the use of such modified earnings numbers and implications for the interpretation of related accounting research. Our results show that over the past 20 years there has been a dramatic increase in the frequency and magnitude of cases where "GAAP" and "Street" earnings differ. Further, there is a very strong bias toward the reporting of a Street earnings number that exceeds the GAAP earnings number. We also show that the market response to the Street earnings number has displaced GAAP earnings as a primary determinant of stock prices. Finally, through an analysis of earnings releases, we show that management has taken a proactive role in defining and emphasizing the Street number when communicating to analysts and investors. [source]


Second Generation Sol-Gel Encapsulated Lipases: Robust Heterogeneous Biocatalysts

ADVANCED SYNTHESIS & CATALYSIS (PREVIOUSLY: JOURNAL FUER PRAKTISCHE CHEMIE), Issue 6-7 2003
Manfred
Abstract The original procedure for the encapsulation of lipases in sol-gel materials produced by the fluoride-catalyzed hydrolysis of mixtures of RSi(OCH3)3 and Si(OCH3)4 has been improved considerably. This involves higher enzyme loading, variation of the alkylsilane precursor, and the use of additives such as isopropyl alcohol, 18-crown-6, Tween,80®, methyl-,-cyclodextrin and/or KCl. A dramatic increase in enzyme activity is observed. The sol-gel lipase immobilizates are also excellent catalysts in the kinetic resolution of chiral alcohols and amines, recycling without any substantial loss in enantioselectivity and a residual activity of 70% being possible even after 20 reaction cycles. [source]


Physically and chemically modified polycarbonate by metal ion implantation

ADVANCES IN POLYMER TECHNOLOGY, Issue 3 2008
Rashi Nathawat
Abstract Changes in physical and chemical properties have been studied for polycarbonate (PC) implanted by 100 keV Ni+ with various fluences from 1 × 1014 to 1 × 1016 ions/cm2. Changes in the surface morphology and composition have been observed with atomic force microscopy and X-ray diffraction (XRD). Ni particles as precipitates in PC were observed by cross-section transmission electron microscopy at the 100-nm depth. Ion implantation induces changes in the topography of PC as indicated by a dramatic increase in surface roughness with ion fluence. Implanted metal ions show direct evidence of compound formation on the surface. Chemical changes in the surface region have been observed by Raman spectroscopy and UV,vis spectroscopy. UV,vis absorption analysis indicates a drastic decline in optical band gap from 5.46 to 1.76 eV at an implanted dose of 1 × 1016 ions/cm2. It is shown that partial destruction of the original chemical bonding under ion implantation leads to the creation of new amorphous and graphite-like structures, which are confirmed by Raman spectroscopy. © 2009 Wiley Periodicals, Inc. Adv Polym Techn 27:143,151, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/adv.20130 [source]


Corporate Cash Policy and How to Manage it with Stock Repurchases

JOURNAL OF APPLIED CORPORATE FINANCE, Issue 3 2008
Amy Dittmar
At the end of 2004 total U.S. corporate cash holdings reached an all-time high of just under $2 trillion,an amount equal to roughly 15% of the total U.S. GDP. And during the past 25 years, average cash holdings have jumped from 10% to 23% of total corporate assets. But at the same time their levels of cash have risen, U.S. companies have paid out dramatically increasing amounts of cash to buy back shares. This article addresses the following questions: What accounts for the dramatic increase in the average level of corporate cash holdings since 1980? And why do some companies keep so much cash (with one fourth of U.S. firms holding cash amounting to at least 36% of total assets) while others have so little (with another quarter having less than 3%)? Why do companies pay out excess cash in the form of stock repurchases (rather than, say, dividends), and what explains the significant increase in repurchases (both in absolute terms and relative to dividends) over time? The author begins by arguing that cash reserves provide companies with a buffer against possible shortfalls in operating profits,one that, especially during periods of financial trouble, can be used to avoid financial distress or provide funding for promising projects that might otherwise have to be put off. Such buffers are particularly valuable in the case of smaller, riskier companies with lots of growth opportunities and limited access to capital markets. And the dramatic increase in corporate cash holdings between 1980 and the present can be attributed mainly to an increase in the risk of publicly traded companies,an increase in risk that reflects in part a general increase in competition, but also a notable change over time in the kinds of companies (smaller, newer, less profitable, non-dividend paying firms) that have chosen to go public. At the other end of the corporate spectrum are large, relatively mature companies with limited growth opportunities. Although such companies tend to produce considerable free cash flow, they also tend to retain relatively small amounts of cash (as a percentage of total assets), in part because of shareholder concern about the corporate "free cash flow problem",the well-documented tendency of such companies to destroy value through overpriced (often diversifying) acquisitions and other misguided attempts to pursue growth at the expense of profitability. For companies with highly predictable earnings and investment plans, dividends provide one means of addressing the free cash flow problem. But for companies with more variable earnings and less predictable reinvestment, open-market stock repurchases provide a more flexible means of distributing cash to shareholders. Unlike the corporate "commitment" implied by dividend payments, an open market stock repurchase program creates what amounts to an option but not an obligation to distribute funds. The value of such flexibility, which increases during periods of increased risk and uncertainty, explains much of the apparent substitution of repurchases for dividends in recent years. [source]