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Maintenance
Kinds of Maintenance Terms modified by Maintenance Selected AbstractsDEMAND UNCERTAINTY AND RESALE PRICE MAINTENANCECONTEMPORARY ECONOMIC POLICY, Issue 4 2000D FLATH When retailers must commit to shipment quantities prior to resolution of demand uncertainty, manufacturer stipulation of a minimum retail price is likely to be profitable for the manufacturer and not damaging to the retailers. The reason is simple: if demand turns out to be low, the unfettered market-clearing price can lie below the price that maximizes total sales revenue. A minimum retail price that is binding in the low-demand state can thus increase total revenue even though it saddles retailers with unsold merchandise. The ubiquity of full reimbursement for returns in Japan, even though it is in theory merely a second-best way of achieving minimum retail price stipulations, reveals important aspects of manufacturer maintenance of retail prices having to do with enforcement problems, the allocation of risk-bearing, and economic incentives. These aspects of resale price maintenance (RPM) are relevant to the normative evaluation of the special exemptions for RPM that Japan's Fair Trade Commission has long maintained but is now phasing out. [source] GEOGRAPHIC VARIATION, FREQUENCY-DEPENDENT SELECTION, AND THE MAINTENANCE OF A FEMALE-LIMITED POLYMORPHISMEVOLUTION, Issue 1 2010Ryan Calsbeek A central problem in evolutionary biology is to understand how spatial and temporal variation in selection maintain genetic variation within and among populations. Brown anole lizards (Anolis sagrei) exhibit a dorsal pattern polymorphism that is expressed only in females, which occur in "diamond,""bar," and intermediate "diamond-bar" morphs. To understand the inheritance of this polymorphism, we conducted a captive breeding study that refuted several single-locus models and supported a two-locus mode of inheritance. To describe geographic variation in morph frequencies, we surveyed 13 populations from two major islands in The Bahamas. Morph frequencies differed substantially between major islands but were highly congruent within each island. Finally, we measured viability selection on each island to test two hypotheses regarding the maintenance of the polymorphism: (1) that spatial variation in selection maintains variation in morph frequencies between islands, and (2) that temporal variation in selection across years maintains variation within islands. Although bar females had relatively lower survival where they were rare, our data do not otherwise suggest that selection varies spatially between islands. However, diamond-bar females were subject to positive frequency-dependent selection across years, and the relative fitness of bar and diamond females alternated across years. We propose that this polymorphism is maintained by temporal variation in selection coupled with the sheltering of alleles via a two-locus inheritance pattern and sex-limited expression. [source] LIFE-HISTORY DIFFERENTIATION AND THE MAINTENANCE OF MONOECY AND DIOECY IN SAGITTARIA LATIFOLIA (ALISMATACEAE)EVOLUTION, Issue 9 2003Marcel E. Dorken Abstract The existence of monoecious and dioecious populations within plant species is rare. This limits opportunities to investigate the ecological mechanisms responsible for the evolution and maintenance of these contrasting sexual systems. In Sagittaria latifolia, an aquatic flowering plant, monoecious and dioecious populations exist in close geographic proximity but occupy distinct wetland habitats differing in the relative importance of disturbance and competition, respectively. Life-history theory predicts contrasting evolutionary responses to these environmental conditions. We propose that the maintenance of monoecy and dioecy in S. latifolia is governed by ecological selection of divergent life-history strategies in contrasting habitats. Here we evaluate this hypothesis by comparing components of growth and reproduction between monoecious and dioecious populations under four conditions: natural populations, a uniform glasshouse environment, a common garden in which monoecious and dioecious populations and their F1 progeny were compared, and a transplant experiment using shaded and unshaded plots in a freshwater marsh. Plants from dioecious populations were larger in size and produced heavier corms in comparison with monoecious populations. Monoecious populations flowered earlier and produced more flowers, clonal ramets, and corms than dioecious populations. The life-history differences between the sexual systems were shown to have a quantitative genetic basis, with F1 progeny generally exhibiting intermediate trait values. Survival was highest for each sexual system in field plots that most closely resembled the habitats in which monoecious (unshaded) and dioecious (shaded) populations grow. These results demonstrate that monoecious and dioecious populations exhibit contrasting patterns of investment in traits involved with growth and reproduction. Selection for divergent life histories between monoecious and dioecious populations of S. latifolia appears to be the principal mechanism maintaining the integrity of the two sexual systems in areas of geographic overlap. [source] MAINTENANCE OF ANDRODIOECY IN THE FRESHWATER SHRIMP, EULIMNADIA TEXANA: ESTIMATES OF INBREEDING DEPRESSION IN TWO POPULATIONSEVOLUTION, Issue 3 2000Stephen C. Weeks Abstract., Androdioecy is an uncommon form of reproduction in which males coexist with hermaphrodites. Androdioecy is thought to be difficult to evolve in species that regularly inbreed. The freshwater shrimp Eulimnadia texana has recently been described as both androdioecious and highly selfing and is thus anomalous. Inbreeding depression is one factor that may maintain males in these populations. Here we examine the extent of "late" inbreeding depression (after sexual maturity) in these clam shrimp using two tests: (1) comparing the fitness of shrimp varying in their levels of individual heterozygosity from two natural populations that differ in overall genetic diversity; and (2) specifically outcrossing and selfing shrimp from these same populations and comparing fitness of the resulting offspring. The effects of inbreeding differed within each population. In the more genetically diverse population, fecundity, size, and mortality were significantly reduced in inbred shrimp. In the less genetically diverse population, none of the fitness measures was significantly lowered in selfed shrimp. Combining estimates of early inbreeding depression from a previous study with current estimates of late inbreeding depression suggests that inbreeding depression is substantial (,= 0.68) in the more diverse population and somewhat lower (,= 0.50) in the less diverse population. However, given that males have higher mortality rates than hermaphrodites, neither estimate of inbreeding depression is large enough to account for the maintenance of males in either population by inbreeding depression alone. Thus, the stability of androdioecy in this system is likely only if hermaphrodites are unable to self-fertilize many of their own eggs when not mated to a male or if male mating success is generally high (or at least high when males are rare). Patterns of fitness responses in the two populations were consistent with the hypothesis that inbreeding depression is caused by partially recessive deleterious alleles, although a formal test of this hypothesis still needs to be conducted. [source] TRAINING, VALIDATION AND MAINTENANCE OF A PANEL TO EVALUATE THE TEXTURE OF DRY BEANS (PHASEOLUS VULGARIS L.)JOURNAL OF SENSORY STUDIES, Issue 3 2008R. ROMERO DEL CASTILLO ABSTRACT The inclusion of dry beans in diets has clear health benefits. However, consumers in developed countries mainly choose beans for their sensory qualities, especially for their texture. This article describes the constitution, training and validation of a panel of judges to evaluate the texture of dry beans. The judges were trained in the perception of different textures, analyzed a wide range of beans and selected seed-coat roughness, seed-coat perceptibility and creaminess/mealiness of the cotyledon as the main attributes to be scored. After training, the panel was capable of discriminating between different varieties of beans and even between beans of the same variety grown at different locations. The analysis of the behavior of the panel in a standard tasting session 2 years after its formation showed that periodic inclusion of samples from the extremes of the scales for the attributes during tasting sessions was sufficient to keep the panel trained. PRACTICAL APPLICATIONS This article could serve as a guide for the training of sensory panels to evaluate the texture of dry beans. It describes the selection of the attributes on which the analysis is based, references for the extreme values of the attributes and how to train the panel. It also provides a practical example of the analysis of the behavior of the panel some time after training. [source] GUIDELINES FOR IMPLEMENTING PREDICTIVE MAINTENANCE*PRODUCTION AND OPERATIONS MANAGEMENT, Issue 2 2002KATHLEEN E. MCKONE Recent advances in predictive maintenance technologies have led many manufacturers to abandon traditional periodic maintenance policies and replace them with predictive maintenance policies. The models in this paper explicitly evaluate the decision to utilize both predictive and periodic maintenance when the objective is to minimize expected maintenance costs per unit time. Renewal theory is used to obtain optimal policies as unique solutions of integral equations that depend on the failure distribution and prediction capabilities. Based on this research, we recommend that practitioners do not abandon the traditional maintenance methods but follow our guidelines for utilizing periodic maintenance in conjunction with the new technologies. [source] Review and Restore for Case-Base MaintenanceCOMPUTATIONAL INTELLIGENCE, Issue 2 2001Thomas Reinartz Case-base maintenance is one of the most important issues for current research in case-based reasoning (CBR). In this article we propose an extended six-step CBR cycle and discuss its two additional steps as part of the maintenance phase of the CBR process. The review step covers assessment and monitoring of the knowledge containers, whereas the restore step actually modifies the contents of the containers according to recommendations resulting from the review step in order to keep the knowledge containers in a usable state. Here we focus our attention on the case base. For the review step, we define several quality measures based on different case and case-base properties that describe specific characteristics of the case base such as correctness, consistency, uniqueness, minimality, and incoherence. Then we use these measures to realize monitoring capabilities for the case-base container that indicate when the restore step is necessary. Finally, we also describe several methods for modifications of the case base in the restore step and their relation to the review step. An initial experimental evaluation shows the appropriateness of the proposed concepts and methods before we conclude the article with a discussion of related work and an outline of future directions to extend these aspects of maintenance in CBR. [source] Management Strategies and Improvement of Performance of Sewer NetworksCOMPUTER-AIDED CIVIL AND INFRASTRUCTURE ENGINEERING, Issue 7 2007Denys Breysse Even when they are conscious about the needs of maintenance to keep the system in a good condition, they lack efficient methods and tools that may help them in taking appropriate decisions. One can say that no really satisfactory and efficient tool exists, enabling the optimization of Inspection, Maintenance, or Rehabilitation (IMR) strategies on such systems. Sewer managers and researchers have been involved for many years in the French National Research Project for Renewal of Non Man Entry Sewer System (RERAU,Réhabilitation des Réseaux d'Assainissement Urbains, in French) to improve their knowledge of these systems and the management policies. During the RERAU project, a specific action has been dedicated to the modeling of asset ageing and maintenance. A special attention has been dedicated to the description of defects and dysfunctions, to the evaluation of performances and its modeling, accounting for its various dimensions (from the point of view of the manager, of the user, of the environment,). After having defined an Index of Technical Performance (ITp), we will introduce the Index of Technical and Economic Performance (ITEp) that is a combined measure of performance (including social costs) and technical costs. This index provides an objective standard tool for managers to compare different alternatives. It is used in the article to compare some simple IMR strategies. It sets the basis of a new method for no-man entry sewer system management, enabling us to analyze the profitableness of investment in terms of both technical and economic performance. [source] Beer Brewing and Consumption in the Maintenance of African Identity by the Enslaved People of the Bahamas, 1783-1834CULTURE, AGRICULTURE, FOOD & ENVIRONMENT, Issue 2 2001Associate Professor Paul Farnsworth First page of article [source] Whole stomach with antro-pyloric nerve preservation as an esophageal substitute: an original techniqueDISEASES OF THE ESOPHAGUS, Issue 2 2004J.-M. Collard SUMMARY., The paper describes an original technique of gastric tailoring in which the two-thirds of the lesser curvature proximal to the crow's foot are denuded flush with the gastric wall, leaving both nerves of Latarjet and the hepatic branches of the left vagus nerve intact. Maintenance of the vagal supply to the antro-pyloric segment in two patients resulted in the presence of peristaltic contractions sweeping over the antrum on simple observation of the antral wall at the end of the procedure and on both upper G-I series and intragastric manometry tracings 6 weeks postoperatively. Gastric exposure to bile on 24-h gastric bile monitoring was normal 6 weeks after the operation. Neither patient had any gastrointestinal symptoms with the exception of early sensations of postprandial fullness when overeating. [source] Predictors for Maintenance of Sinus Rhythm after Cardioversion in Patients with Nonvalvular Atrial FibrillationECHOCARDIOGRAPHY, Issue 5 2002Ökçün M.D. Recurrence of atrial fibrillation (AF) after cardioversion (CV) to sinus rhythm (SR) is determined by various clinical and echocardiographic parameters. Transesophageal echocardiographic (TEE) parameters have been the focus of clinicians' interests for restoring and maintaining SR. This study determined the clinical, transthoracic, and TEE parameters that predict maintenance of SR in patients with nonvalvular AF after CV. We enrolled 173 patients with nonvalvular AF in the study. TEE could not be performed in 26 patients prior to CV. Twenty-five patients had spontaneously CV prior to TEE. Six patients were excluded because of left atrial (LA) thrombus assessed by TEE. CV was unsuccessful in 6 patients. The remaining 110 consecutive patients (56 men, 54 women, mean age 69 ± 9 years), who had been successfully cardioverted to SR, were prospectively included in the study. Fifty-seven (52%) patients were still in SR 6 months after CV. Age, gender, the configuration of the fibrillation wave on the electrocardiogram, pulmonary venous diastolic flow, and the presence of diabetes, hypertension, coronary artery disease, mitral annulus calcification, and mitral valve prolapse (MVP) did not predict recurrence. Duration of AF, presence of chronic obstructive pulmonary disease (COPD), LA diameter, left ventricular ejection fraction (EF), left atrial appendage peak flow (LAAPF), LAA ejection fraction (LAAEF), pulmonary venous systolic flow (PVSF), and the presence of LA spontaneous echo contrast (LASEC) predicted recurrence of AF 6 months after CV. In multivariate analysis, LAAEF < 30% was found to be the only independent variable (P < 0.0012) predicting recurrence at 6 months after CV in patients with nonvalvular AF. LAAEF more than 30% had a sensitivity of 75% and a specificity of 88% in predicting maintenance of SR 6 months after CV in patients with nonvalvular AF. In conclusion, TEE variables often used to determine thromboembolic risk also might be used to predict the outcome of CV. [source] Maintenance of narrow diet breadth in the monarch butterfly caterpillar: response to various plant species and chemicalsENTOMOLOGIA EXPERIMENTALIS ET APPLICATA, Issue 2-3 2002Danel B. Vickerman Abstract In order to better understand the maintenance of a fairly narrow diet breadth in monarch butterfly larvae, Danaus plexippus L. (Lepidoptera: Nymphalidae: Danainae), we measured feeding preference and survival on host and non-host plant species, and sensitivity to host and non-host plant chemicals. For the plant species tested, a hierarchy of feeding preferences was observed; only plants from the Asclepiadaceae were more or equally preferred to Asclepias curassavica, the common control. The feeding preferences among plant species within the Asclepiadaceae are similar to published mean cardenolide concentrations. However, since cardenolide data were not collected from individual plants tested, definitive conclusions regarding cardenolide concentrations and plant acceptability cannot be made. Although several non-Asclepiadaceae were eaten in small quantities, all were less preferred to A. curassavica. Additionally, these non-Asclepiadaceae do not support continued feeding, development, and survival of first and fifth-instar larvae. Preference for a host versus a non-host (A. curassavica versus Vinca rosea) increased for A. curassavica reared larvae as compared to diet-reared larvae suggesting plasticity in larval food preferences. Furthermore, host species were significantly preferred over non-host plant species in bioassays using a host plant or sucrose as a common control. Larval responses to pure chemicals were examined in order to determine if host and non-host chemicals stimulate or deter feeding in monarch larvae. We found that larvae were stimulated to feed by some ubiquitous plant chemicals, such as sucrose, inositol, and rutin. In contrast, several non-host plant chemicals deterred feeding: caffeine, apocynin, gossypol, tomatine, atropine, quercitrin, and sinigrin. Additionally the cardenolides digitoxin and ouabain, which are not in milkweed plants, were neutral in their influence on feeding. Another non-milkweed cardenolide, cymarin, significantly deterred feeding. Extracts of A. curassavica leaves were tested in bioassays to determine which components of the leaf stimulate feeding. Both an ethanol extract of whole leaves and a hexane leaf-surface extract are phagostimulatory, suggesting the involvement of both polar and non-polar plant compounds. These data suggest that the host range of D. plexippus larvae is maintained by both feeding stimulatory and deterrent chemicals in host and non-host plants. [source] Results of the PETHEMA ALL-96 trial in elderly patients with Philadelphia chromosome-negative acute lymphoblastic leukemiaEUROPEAN JOURNAL OF HAEMATOLOGY, Issue 2 2007Juan-Manuel Sancho Abstract Background and aim:,Only 20,30% of elderly patients with acute lymphoblastic leukemia (ALL) are enrolled in clinical trials because of co-morbid disorders or poor performance status. We present the results of treatment of Philadelphia chromosome-negative (Ph,) ALL patients over 55 yr treated in the PETHEMA ALL-96 trial. Patients and methods:,From 1996 to 2006, 33 patients 55 yr with Ph, ALL were included. Induction therapy was vincristine, daunorubicin, prednisone, asparaginase, and cyclophosphamide over 5 weeks. Central nervous system (CNS) prophylaxis involved triple intrathecal (IT) therapy, 14 doses over the first year. Consolidation-1 included mercaptopurine, methotrexate, teniposide and cytarabine, followed by one consolidation-2 cycle similar to the induction cycle. Maintenance consisted of mercaptopurine and methotrexate up to 2 yr in complete remission (CR) with monthly reinduction cycles (vincristine, prednisone and asparaginase) during the first year. Results:,Median (range) age was 65 yr (56,77). Phenotype (30 patients): early-pre-B 7, common/pre-B 18, T 5. Cytogenetics (28 patients): normal 12, complex 10, t(4;11) 2 and other 4. CR was achieved in 19/33 (57.6%) patients, early death occurred in 12 (36.4%) and 2 (6%) were resistant. Overall survival and disease-free survival probabilities (2 yr, 95% CI) were 39% (21%,57%) and 46% (22%,70%), respectively (median follow up of 24 months). Removal of asparaginase and cyclophosphamide from the induction decreased induction death (OR 0.119, CI 95% 0.022,0.637, P = 0.013) and increased survival (20% vs. 52%, P = 0.05). Conclusions:,The prognosis of elderly Ph, ALL patients is poor. In this study, less intensive induction decreased toxic death, allowing delivery of planned consolidation therapy and increased survival probability. [source] Maintenance of CCL5 mRNA stores by post-effector and memory CD8 T cells is dependent on transcription and is coupled to increased mRNA stabilityEUROPEAN JOURNAL OF IMMUNOLOGY, Issue 10 2006Antoine Marçais Abstract Immunological memory is associated with the display of improved effector functions by cells of the adaptive immune system. The storage of untranslated mRNA coding for the CCL5 chemokine by CD8 memory cells is a new process supporting the immediate display of an effector function. Here, we show that, after induction during the primary response, high CCL5 mRNA levels are specifically preserved in CD8 T cells. We have investigated the mechanisms involved in the long-term maintenance of CCL5 mRNA levels by memory CD8 T cells. We demonstrate that the CCL5 mRNA half-life is increased in memory CD8 T cells and that these cells constitutively transcribe ccl5 gene. By inhibiting ccl5 transcription using IL-4, we demonstrate the essential role of transcription in the maintenance of CCL5 mRNA stores. Finally, we show that these stores are spontaneously reconstituted when the inhibitory signal is removed, indicating that the transcription of ccl5 is a default feature of memory CD8 T cells imprinted in their genetic program. [source] Maintenance of the relative proportion of oligodendrocytes to axons even in the absence of BAX and BAKEUROPEAN JOURNAL OF NEUROSCIENCE, Issue 11 2009Kumi Kawai Abstract Highly purified oligodendroglial lineage cells from mice lacking functional bax and bak genes were resistant to apoptosis after in-vitro differentiation, indicating an essential role of the intrinsic apoptotic pathway in apoptosis of oligodendrocytes in the absence of neurons (axons) and other glial cells. These mice therefore provide a valuable tool with which to evaluate the significance of the intrinsic apoptotic pathway in regulating the population sizes of oligodendrocytes and oligodendroglial progenitor cells. Quantitative analysis of the optic nerves and the dorsal columns of the spinal cord revealed that the absolute numbers of mature oligodendrocytes immunolabeled for aspartoacylase and adult glial progenitor cells expressing NG2 chondroitin sulfate proteoglycan were increased in both white matter tracts of adult bax/bak -deficient mice and, to a lesser extent, bax -deficient mice, except that there was no increase in NG2-positive progenitor cells in the dorsal columns of these strains of mutant mice. These increases in mature oligodendrocytes and progenitor cells in bax/bak -deficient mice were unexpectedly proportional to increases in numbers of axons in these white matter tracts, thus retaining the oligodendroglial lineage to axon ratios of at most 1.3-fold of the physiological numbers. This is in contrast to the prominent expansion in numbers of neural precursor cells in the subventricular zones of these adult mutant mice. Our study indicates that homeostatic control of cell number is different for progenitors of the oligodendroglial and neuronal lineages. Furthermore, regulatory mechanism(s) operating in addition to apoptotic elimination through the intrinsic pathway, appear to prevent the overproduction of highly mitotic oligodendroglial progenitor cells. [source] Translation of an integral membrane protein in distal dendrites of hippocampal neuronsEUROPEAN JOURNAL OF NEUROSCIENCE, Issue 6 2005Jeffrey C. Grigston Abstract Maintenance of synaptic plasticity requires protein translation. Because changes in synaptic strength are regulated at the level of individual synapses, a mechanism is required for newly translated proteins to specifically and persistently modify only a subset of synapses. Evidence suggests this may be accomplished through local translation of proteins at or near synapses in response to plasticity-inducing patterns of activity. A number of proteins important for synaptic function are integral membrane proteins, which require a specialized group of organelles, proteins and enzymatic activities for proper synthesis. Dendrites appear to contain machinery necessary for the proper production of these proteins, and mRNAs for integral membrane proteins have been found localized to dendrites. Experiments are described that investigate the local translation of membrane proteins in the dendrites of cultured rat hippocampal neurons, using fluorescence recovery after photobleaching. Neurons were transfected with cDNAs encoding a fluorescently labeled transmembrane protein, TGN-38. Under conditions where the transport of this reporter construct was inhibited, the appearance of newly synthesized protein was observed via fluorescent microscopy. The dendritic translation of this protein required activation of glutamate receptors. The results demonstrate a functional capacity for activity-dependent synthesis of integral membrane proteins for distal dendrites in hippocampal neurons. [source] Maintenance and Change in the Diet of Hispanic Immigrants in Eastern North CarolinaFAMILY & CONSUMER SCIENCES RESEARCH JOURNAL, Issue 4 2001Laura H. McArthur The objectives of this descriptive, exploratory study were to assess maintenance and change in the food consumption, preparation, and purchasing practices of Hispanic immigrants currently residing in eastern North Carolina who had lived in the United States for no more than 10 years, and to identify underlying ecological factors and perceptions about food quality that shape their postmigrational food habits. The participants were 33 Hispanic immigrants: 8 males and 25 females. Qualitative data were collected using individual interviews and a focus group session. Findings suggest that these Hispanic immigrants struggle to retain their cultural food traditions and are consuming more high-fat, high-sugar foods than they did in their home countries. Improved economic status and school food service offerings are examples of factors that promote dietary change among children and families. These influences and identified misconceptions about food safety and freshness are important topics for culturally sensitive nutrition education for this population. [source] Intracellular pH homeostasis in the filamentous fungus Aspergillus nigerFEBS JOURNAL, Issue 14 2002Stephan J. A. Hesse Intracellular pH homeostasis in the filamentous fungus Aspergillus niger was measured in real time by 31P NMR during perfusion in the NMR tube of fungal biomass immobilized in Ca2+ -alginate beads. The fungus maintained constant cytoplasmic pH (pHcyt) and vacuolar pH (pHvac) values of 7.6 and 6.2, respectively, when the extracellular pH (pHex) was varied between 1.5 and 7.0 in the presence of citrate. Intracellular metabolism did not collapse until a ,pH over the cytoplasmic membrane of 6.6,6.7 was reached (pHex 0.7,0.8). Maintenance of these large pH differences was possible without increased respiration compared to pHex 5.8. Perfusion in the presence of various hexoses and pentoses (pHex 5.8) revealed that the magnitude of ,pH values over the cytoplasmic and vacuolar membrane could be linked to the carbon catabolite repressing properties of the carbon source. Also, larger ,pH values coincided with a higher degree of respiration and increased accumulation of polyphosphate. Addition of protonophore (carbonyl cyanide m -chlorophenylhydrazone, CCCP) to the perfusion buffer led to decreased ATP levels, increased respiration and a partial (1 µm CCCP), transient (2 µm CCCP) or permanent (10 µm CCCP) collapse of the vacuolar membrane ,pH. Nonlethal levels of the metabolic inhibitor azide (N3,, 0.1 mm) caused a transient decrease in pHcyt that was closely paralleled by a transient vacuolar acidification. Vacuolar H+ influx in response to cytoplasmic acidification, also observed during extreme medium acidification, indicates a role in pH homeostasis for this organelle. Finally, 31P NMR spectra of citric acid producing A. niger mycelium showed that despite a combination of low pHex (1.8) and a high acid-secreting capacity, pHcyt and pHvac values were still well maintained (pH 7.5 and 6.4, respectively). [source] Maintenance of a small anadromous subpopulation of brown trout (Salmo trutta L.) by strayingFRESHWATER BIOLOGY, Issue 2 2006F. AYLLON Summary 1. Microsatellite and isozyme loci variation were used to study structure and dynamics of a brown trout (Salmo trutta) population heavily affected by damming. The downstream area accessible for spawning was drastically reduced to a stream 1 km long influenced by regulated discharge. 2. Stocking of hatchery-reared juveniles failed and the population is entirely supported by anadromous adults from neighbouring populations. 3. Temporal genetic stability is reported here. Some punctual between-river genetic differences are likely because of different contribution from each neighbouring river through years. 4. High anadromy-mediated gene flow produces a lack of genetic substructure in the region. The role of anadromous brown trout on maintenance of endangered small populations is emphasised. [source] Maintenance of the alcohol dehydrogenase polymorphism in Tiger Salamanders, II.FUNCTIONAL ECOLOGY, Issue 1 2000Differences in biochemical function among allozymes Abstract 1.,Previous studies of Tiger Salamanders demonstrated that variation in alcohol dehydrogenase (Adh) contributed significantly to associations between multilocus heterozygosity and oxygen consumption traits, and that Adh variation was associated with levels of pond-oxygen and metamorphic ability in extreme oxygen environments. Here Adh allozymes are characterized kinetically, and relationships between Adh and oxygen-related physiological traits (ATP/Hb, 2,3-DPG/Hb) are measured. 2.,Kinetic differences were measured among Adh allozymes in the acetaldehyde-to-ethanol direction: kcat/Km ratios (the catalytic constant divided by the Michaelis,Menton constant) were significantly higher in Adh-SF than the other two genotypes, and in Adh-SS compared with Adh-FF. No significant differences were measured in the ethanol to acetaldehyde direction. 3.,Adh-SS had a significantly higher ATP/Hb than Adh-FF, with the Adh-SF intermediate. In addition, a significant interaction between Hb and body mass was measured, such that Adh-FF showed a negative relationship between Hb concentration and body mass while the other two genotypes showed a positive relationship. 4.,These results are consistent with the hypothesis that variation at the Adh locus has adaptive and physiological significance, and that functional differences among Adh allozymes partly explain significant associations between multilocus genotype and organismal traits. [source] Maintenance of self-renewal ability of mouse embryonic stem cells in the absence of DNA methyltransferases Dnmt1, Dnmt3a and Dnmt3bGENES TO CELLS, Issue 7 2006Akiko Tsumura DNA methyltransferases Dnmt1, Dnmt3a and Dnmt3b cooperatively regulate cytosine methylation in CpG dinucleotides in mammalian genomes, providing an epigenetic basis for gene silencing and maintenance of genome integrity. Proper CpG methylation is required for the normal growth of various somatic cell types, indicating its essential role in the basic cellular function of mammalian cells. Previous studies using Dnmt1,/, or Dnmt3a,/,Dnmt3b,/, ES cells, however, have shown that undifferentiated embryonic stem (ES) cells can tolerate hypomethylation for their proliferation. In an attempt to investigate the effects of the complete loss of CpG DNA methyltransferase function, we established mouse ES cells lacking all three of these enzymes by gene targeting. Despite the absence of CpG methylation, as demonstrated by genome-wide methylation analysis, these triple knockout (TKO) ES cells grew robustly and maintained their undifferentiated characteristics. TKO ES cells retained pericentromeric heterochromatin domains marked with methylation at Lys9 of histone H3 and heterochromatin protein-1, and maintained their normal chromosome numbers. Our results indicate that ES cells can maintain stem cell properties and chromosomal stability in the absence of CpG methylation and CpG DNA methyltransferases. [source] Comprehensive Inpatient Treatment of Refractory Chronic Daily HeadacheHEADACHE, Issue 4 2009Alvin E. Lake III PhD Objective., (1) To assess outcome at discharge for a consecutive series of admissions to a comprehensive, multidisciplinary inpatient headache unit; (2) To identify outcome predictors. Background., An evidence-based assessment (2004) concluded that many refractory headache patients appear to benefit from inpatient treatment, underscoring the need for more research, including outcome predictors. Methods., The authors completed a retrospective chart review of 283 consecutive admissions over 6 months. The inpatient program (mean length of stay = 13.0 days) included intravenous and oral medication protocols, drug withdrawal when indicated, cognitive-behavior therapy, and other services when needed, including anesthesiological intervention. Patient-reported pain levels and consensus of medical staff determined outcome status. Results., The 267 completers (94%) included 212 women and 55 men (mean age = 40.3 years, range = 13-74) from 43 states and Canada. The modal diagnosis was intractable, chronic daily headache (85%), predominantly migraine. Most (59%) had medication overuse headache (MOH), involving opioids (48%), triptans (16%), or butalbital-containing analgesics (10%). Psychiatric diagnoses included stress-related headache (82%), mood disorders (70%), anxiety disorders (49%), and personality disorders (PD, 26%). More patients with a PD (62%) had opioid-related MOH than those with no PD (38%), P < .005. Of the completers, 78% had moderate to significant pain reduction, with comparable improvement in mood, function, and behavior. Clinical factors predicting moderate-significant headache improvement were limited to MOH (84% vs 69%, P < .007) and presence of a PD (68% vs 81%, P < .03). Conclusions., Most patients (78%) improved following aggressive, comprehensive inpatient treatment. Maintenance of improvement is likely to depend on multiple post-discharge factors, including continuity of care, compliance, and home or work environment. [source] Whole-system approaches to health and social care partnerships for the frail elderly: an exploration of North American models and lessonsHEALTH & SOCIAL CARE IN THE COMMUNITY, Issue 5 2006Dennis L. Kodner PhD Abstract Irrespective of cross-national differences in long-term care, countries confront broadly similar challenges, including fragmented services, disjointed care, less-than-optimal quality, system inefficiencies and difficult-to-control costs. Integrated or whole-system strategies are becoming increasingly important to address these shortcomings through the seamless provision of health and social care. North America is an especially fertile proving ground for structurally oriented whole-system models. This article summarises the structure, features and outcomes of the Program of All-Inclusive Care for Elderly People (PACE) programme in the United States, and the Système de soins Intégrés pour Personnes Âgées (SIPA) and the Programme of Research to Integrate Services for the Maintenance of Autonomy (PRISMA) in Canada. The review finds a somewhat positive pattern of results in terms of service access, utilisation, costs, care provision, quality, health status and client/carer satisfaction. It concludes with the identification of common characteristics which are thought to be associated with the successful impact of these partnership initiatives, as well as a call for further research to understand the relationships, if any, between whole-system models, services and outcomes in integrated care for elderly people. [source] TPM,Total Productive Maintenance: Impact on competitiveness and a framework for successful implementationHUMAN FACTORS AND ERGONOMICS IN MANUFACTURING & SERVICE INDUSTRIES, Issue 4 2001K.S. Park Total Productive Maintenance (TPM) describes a synergistic relationship among all organizational functions, but particularly between production and maintenance, for continuous improvement of product quality, operational efficiency, capacity assurance, and safety. This article provides the key factors that are critical to the successful implementation of TPM. It is thus crucial to provide and discuss those factors for more effective TPM implementation. Also, this study explores the impact of TPM on the competitiveness of the company. This research concludes that long-term benefits of TPM are the result of considerable investment in human resource development and management. For TPM practitioners, we advise to build a supportive culture and environment with a strong emphasis on human and organizational aspects to promote effective TPM implementation. © 2001 John Wiley & Sons, Inc. [source] Distal goal and proximal goal transfer of training interventions in an executive education programHUMAN RESOURCE DEVELOPMENT QUARTERLY, Issue 3 2009Travor C. Brown This study assessed transfer from a customized executive training program involving 89 public sector employees. Participants who set a distal goal had higher self-efficacy than those in both the "do your best" (DYB) and the proximal plus distal goal conditions. Participants who set proximal plus distal goals had higher maintenance than those who set distal outcome goals, and those who were urged to DYB. The distal goal participants had a higher level of applied generalization than their DYB counterparts. Maintenance did not differ between DYB and distal goal conditions. [source] The Apotheosis of Home and the Maintenance of Spaces of ViolenceHYPATIA, Issue 4 2002JOSHUA M. PRICE The "Home" is ideologically understood as a place of safety and refuge. Such an account cloaks violence against women. The voices of battered women can disrupt that dominant construction of the space of the home, a construction typified by the work of Gaston Bachelard. The space that Bachelard presupposes and theorizes as given is in fact being-produced, cleaned, and organized by people who themselves may not find in it any solace or respite. [source] Germ-line transformation of pink bollworm (Lepidoptera: Gelechiidae) mediated by the piggyBac transposable elementINSECT MOLECULAR BIOLOGY, Issue 3 2000J. J. Peloquin Abstract The pink bollworm, Pectinophora gossypiella, is a world-wide pest of cultivated cotton. In certain growing regions populations are suppressed by a sterile release strategy. Efforts to improve the sterile insect technique as well as our understanding of lepidopteran biology could benefit greatly from a germ-line transformation system. We report transformation of pink bollworm with a piggyBac transposable element carrying the enhanced green flourescent protein (EGFP) marker gene. This vector,marker system resulted in recovery of transgenics at a rate of approximately 3.5%. Integration of the transforming construct that was typical of piggyBac was demonstrated by Southern analysis and sequence determination of transposon flanks. Expression of the EGFP marker was visualized by fluorescent microscopy and Western Blot analysis. Maintenance of transformed strains indicates that the transgene segregates in a Mendelian fashion and has been stable over fourteen generations to date. [source] Maintenance of internet-based prevention: A randomized controlled trialINTERNATIONAL JOURNAL OF EATING DISORDERS, Issue 2 2007Corinna Jacobi PhD Abstract Objective: Excessive weight or shape concerns and dieting are among the most important and well-established risk factors for the development of symptoms of disordered eating or full-syndrome eating disorders. Prevention programs should therefore target these factors in order to reduce the likelihood of developing an eating disorder. The aims of this study were to determine the short-term and maintenance effects of an internet-based prevention program for eating disorders. Method: One hundred female students at two German universities were randomly assigned to either an 8-week intervention or a waiting-list control condition and assessed at preintervention, postintervention, and 3-month follow-up. Results: Compared with the control group, the intervention produced significant and sustained effects for high-risk women. Conclusion: Internet-based prevention is effective and can be successfully adapted to a different culture. © 2006 by Wiley Periodicals, Inc. Int J Eat Disord 2006 [source] University timetabling through conceptual modelingINTERNATIONAL JOURNAL OF INTELLIGENT SYSTEMS, Issue 11 2005Jonathan Lee A number of approaches have been proposed in tackling the timetabling problem, such as operational research, human-machine interaction, constraint programming, expert systems, and neural networks. However, there are still several key challenges to be addressed: easily reformulated to support changes, a generalized framework to handle various timetabling problems, and ability to incorporate knowledge in the timetabling system. In this article, we propose an automatic software engineering approach, called task-based conceptual graphs, to addressing the challenges in the timetabling problem. Task-based conceptual graphs provide the automation of software development processes including specification, verification, and automatic programming. Maintenance can be directly performed on the specifications rather than on the source code; moreover, hard and soft constraints can be easily inserted or removed. A university timetabling system in the Department of Computer Science and Information Engineering at National Central University is used as an illustrative example for the proposed approach. © 2005 Wiley Periodicals, Inc. Int J Int Syst 20: 1137,1160, 2005. [source] Proteasome activation as a novel antiaging strategyIUBMB LIFE, Issue 10 2008Niki Chondrogianni Abstract Homeostasis is a key feature of cellular lifespan. Maintenance of cellular homeostasis influences the rate of aging and is determined by several factors, including efficient proteolysis of damaged proteins. Protein degradation is predominately catalyzed by the proteasome. Specifically, the proteasome is responsible for cell clearance of abnormal, denatured or in general damaged proteins as well as for the regulated degradation of short-lived proteins. As proteasome has an impaired function during aging, emphasis has been given recently in identifying ways of its activation. A number of studies have shown that the proteasome can be activated by genetic manipulations as well as by factors that affect its conformation and stability. Importantly the developed proteasome activated cell lines exhibit an extended lifespan. This review article discusses in details the various factors that are involved in proteasome biosynthesis and assembly and how they contribute to its activation. Finally as few natural compounds have been identified having proteasome activation properties, we discuss the advantages of this novel antiaging strategy. © 2008 IUBMB IUBMB Life, 60(10): 651,655, 2008 [source] | ||||||||||||||||||||||||||||||||||||||||||||||||||||