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Sample records for protein turnover showed

  1. Changes of Protein Turnover in Aging Caenorhabditis elegans

    Energy Technology Data Exchange (ETDEWEB)

    Dhondt, Ineke; Petyuk, Vladislav A.; Bauer, Sophie; Brewer, Heather M.; Smith, Richard D.; Depuydt, Geert; Braeckman, Bart P.

    2017-07-05

    Protein turnover rates severely decline in aging organisms, including C. elegans. However, limited information is available on turnover dynamics at the individual protein level during aging. We followed changes in protein turnover at one-day resolution using a multiple-pulse 15Nlabeling and accurate mass spectrometry approach. Forty percent of the proteome shows gradual slowdown in turnover with age, whereas only few proteins show increased turnover. Decrease in protein turnover was consistent for only a minority of functionally related protein subsets, including tubulins and vitellogenins, whereas randomly diverging turnover patterns with age were the norm. Our data suggests increased heterogeneity of protein turnover of the translation machinery, whereas protein turnover of ubiquitin-proteasome and antioxidant systems are well-preserved over time. Hence, we presume that maintenance of quality control mechanisms is a protective strategy in aging worms, although the ultimate proteome collapse is inescapable.

  2. Regulatory mechanisms of skeletal muscle protein turnover during exercise

    DEFF Research Database (Denmark)

    Rose, Adam John; Richter, Erik

    2009-01-01

    Skeletal muscle protein turnover is a relatively slow metabolic process that is altered by various physiological stimuli such as feeding/fasting and exercise. During exercise, catabolism of amino acids contributes very little to ATP turnover in working muscle. With regards to protein turnover......, there is now consistent data from tracer studies in rodents and humans showing that global protein synthesis is blunted in working skeletal muscle. Whether there is altered skeletal muscle protein breakdown during exercise remains unclear. The blunting of protein synthesis is believed to be mediated...... downstream of changes in intracellular Ca(2+) and energy turnover. In particular, a signaling cascade involving Ca(2+)-calmodulin-eEF2 kinase-eEF2 is implicated. The possible functional significance of altered protein turnover in working skeletal muscle during exercise is discussed. Further work...

  3. Systematic analysis of protein turnover in primary cells.

    Science.gov (United States)

    Mathieson, Toby; Franken, Holger; Kosinski, Jan; Kurzawa, Nils; Zinn, Nico; Sweetman, Gavain; Poeckel, Daniel; Ratnu, Vikram S; Schramm, Maike; Becher, Isabelle; Steidel, Michael; Noh, Kyung-Min; Bergamini, Giovanna; Beck, Martin; Bantscheff, Marcus; Savitski, Mikhail M

    2018-02-15

    A better understanding of proteostasis in health and disease requires robust methods to determine protein half-lives. Here we improve the precision and accuracy of peptide ion intensity-based quantification, enabling more accurate protein turnover determination in non-dividing cells by dynamic SILAC-based proteomics. This approach allows exact determination of protein half-lives ranging from 10 to >1000 h. We identified 4000-6000 proteins in several non-dividing cell types, corresponding to 9699 unique protein identifications over the entire data set. We observed similar protein half-lives in B-cells, natural killer cells and monocytes, whereas hepatocytes and mouse embryonic neurons show substantial differences. Our data set extends and statistically validates the previous observation that subunits of protein complexes tend to have coherent turnover. Moreover, analysis of different proteasome and nuclear pore complex assemblies suggests that their turnover rate is architecture dependent. These results illustrate that our approach allows investigating protein turnover and its implications in various cell types.

  4. Protein turnover in sheep

    International Nuclear Information System (INIS)

    Buttery, P.J.

    1981-01-01

    Considerable advances have been made in the knowledge of the mechanisms and control of synthesis and degradation of proteins in animal tissues during the last decade. Most of the work on the measurement of synthetic and degradative rates of the mixed protein fraction from tissues has been conducted in the rat. There have, unfortunately, been few publications describing results of protein turnover studies with ruminants. Consideration is given here to the techniques used to measure protein turnover, and some of the results obtained, particularly with sheep, are summarized. No attempt has been made to discuss directly the situation in parasitized animals; rather the aim is to provide background information which complements other work dealing with the effects of parasites on the nitrogen metabolism of ruminants. (author)

  5. The research methods and model of protein turnover in animal

    International Nuclear Information System (INIS)

    Wu Xilin; Yang Feng

    2002-01-01

    The author discussed the concept and research methods of protein turnover in animal body. The existing problems and the research results of animal protein turnover in recent years were presented. Meanwhile, the measures to improve the models of animal protein turnover were analyzed

  6. Investigation on the turnover of plant proteins. 2

    International Nuclear Information System (INIS)

    Becker, R.; Winkler, E.; Jung, K.; Huebner, G.

    1981-01-01

    Based on kinetic analyses of amino acid and protein turnover by means of compartment models the synthesis and degradation of the soluble proteins in etiolated epicotyl segments of Pisum sativum L. as well as their dependence on the herbicide 2'-methyl-4'-chlorophenoxyacetic acid (MCPA) were determined quantitatively. The segments were incubated for 10 h in a medium containing 14 C-leucine and subsequently placed in an inactive medium. The radioactivity in the soluble proteins and in the amino acid fraction was followed up for a total of 24 h. A 3-pool model in which the total measurable amino acid pool was divided into a direct precursor pool for protein synthesis and into a degradation pool was best suited to interpret the data. The turnover rate for the soluble proteins of untreated epicotyl segments was determined to be 0.058 h -1 ; at an MCPA concentration of 10 -4 M this value was nearly doubled. An increased proteolytic activity in the epicotyl segments ran parallel to the change of the turnover rate in dependence on MCPA concentration. The heterogeneity of the soluble protein with respect to the turnover rate was investigated by means of 3 H/ 14 C double labelling for individual protein fractions separated by gel electrophoresis. The results obtained in this way were comparable with those of the total pool turnover. (author)

  7. Measurements of protein turnover in man with nitrogen-15

    International Nuclear Information System (INIS)

    Garlick, P.J.; Waterlow, J.C.

    1977-01-01

    Past and present methods of measuring total body protein turnover with 15 N-labelled compounds are reviewed, and a short assessment made of results achieved. Protein turnover in man was first measured by Sprinson and Rittenberg (1949) using 15 N glycine as tracer. The rate of turnover was calculated from the fraction of the dose excreted in urine in the days following a single oral dose of the isotope. In the following years a number of similar methods were devised but interest waned, perhaps because consistent changes in turnover rate under different conditions were not detected. A revival of interest came with the measurement of changes in protein turnover in malnourished and recovering children by Picou and Taylor-Roberts (1969). Nitrogen-15-glycine was infused and measurements were made of the abundance of 15 N in urinary urea, which reached a plateau in about 24 hours. Turnover rates were calculated from the proportion of the infused dose excreted in urea after the plateau had been reached. This method has also been used successfully on adults when the isotope has been given as three-hourly oral doses. In adults, however, plateau labelling in urea is not usually reached for two days. In our laboratory the use of urinary ammonia, which reaches a plateau more quickly than urea, has been examined. In addition, comparisons have been made between constant infusion and single dose of isotope. Halliday and McKeran (1975) infused 15 N-lysine and measured the 15 N abundance in the free lysine of plasma, which reached a plateau in about 12 hours. Turnover in the whole body and turnover of muscle proteins and of plasma albumin were estimated separately. These methods of measuring protein turnover with 15 N are described and results reviewed of the effects of food intake, nutritional status and age. (author)

  8. Plasma Protein Turnover Rates in Rats Using Stable Isotope Labeling, Global Proteomics, and Activity-Based Protein Profiling

    Energy Technology Data Exchange (ETDEWEB)

    Smith, Jordan N.; Tyrrell, Kimberly J.; Hansen, Joshua R.; Thomas, Dennis G.; Murphree, Taylor A.; Shukla, Anil K.; Luders, Teresa; Madden, James M.; Li, Yunying; Wright, Aaron T.; Piehowski, Paul D.

    2017-12-06

    Protein turnover is important for general health on cellular and organism scales providing a strategy to replace old, damaged, or dysfunctional proteins. Protein turnover also informs of biomarker kinetics, as a better understanding of synthesis and degradation of proteins increases the clinical utility of biomarkers. Here, turnover rates of plasma proteins in rats were measured in vivo using a pulse-chase stable isotope labeling experiment. During the pulse, rats (n=5) were fed 13C6-labeled lysine (“heavy”) feed for 23 days to label proteins. During the chase, feed was changed to an unlabeled equivalent feed (“light”), and blood was repeatedly sampled from rats over 10 time points for 28 days. Plasma samples were digested with trypsin, and analyzed with liquid chromatography-tandem mass spectrometry (LC-MS/MS). MaxQuant was used to identify peptides and proteins, and quantify heavy:light lysine ratios. A system of ordinary differential equations was used to calculate protein turnover rates. Using this approach, 273 proteins were identified, and turnover rates were quantified for 157 plasma proteins with half-lives ranging 0.3-103 days. For the ~70 most abundant proteins, variability in turnover rates among rats was low (median coefficient of variation: 0.09). Activity-based protein profiling was applied to pooled plasma samples to enrich serine hydrolases using a fluorophosphonate (FP2) activity-based probe. This enrichment resulted in turnover rates for an additional 17 proteins. This study is the first to measure global plasma protein turnover rates in rats in vivo, measure variability of protein turnover rates in any animal model, and utilize activity-based protein profiling for enhancing measurements of targeted, low-abundant proteins, such as those commonly used as biomarkers. Measured protein turnover rates will be important for understanding of the role of protein turnover in cellular and organism health as well as increasing the utility of protein

  9. A high protein diet upregulated whole-body protein turnover during energy deficit

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    The effects of higher protein diets and sustained energy deficit (ED) on whole-body protein turnover (WBPTO) are not well described. This study examined whether dietary protein level influences whole-body protein breakdown (Ra), non-oxidative leucine disposal (NOLD), and oxidation (Ox) during ED. ...

  10. Protein Turnover Measurements in Human Serum by Serial Immunoaffinity LC-MS/MS.

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    Farrokhi, Vahid; Chen, Xiaoying; Neubert, Hendrik

    2018-02-01

    The half-life of target proteins is frequently an important parameter in mechanistic pharmacokinetic and pharmacodynamic (PK/PD) modeling of biotherapeutics. Clinical studies for accurate measurement of physiologically relevant protein turnover can reduce the uncertainty in PK/PD model-based predictions, for example, of the therapeutic dose and dosing regimen in first-in-human clinical trials. We used a targeted mass spectrometry work flow based on serial immunoaffinity enrichment ofmultiple human serum proteins from a [5,5,5- 2 H 3 ]-L-leucine tracer pulse-chase study in healthy volunteers. To confirm the reproducibility of turnover measurements from serial immunoaffinity enrichment, multiple aliquots from the same sample set were subjected to protein turnover analysis in varying order. Tracer incorporation was measured by multiple-reaction-monitoring mass spectrometry and target turnover was calculated using a four-compartment pharmacokinetic model. Five proteins of clinical or therapeutic relevance including soluble tumor necrosis factor receptor superfamily member 12A, tissue factor pathway inhibitor, soluble interleukin 1 receptor like 1, soluble mucosal addressin cell adhesion molecule 1, and muscle-specific creatine kinase were sequentially subjected to turnover analysis from the same human serum sample. Calculated half-lives ranged from 5-15 h; however, no tracer incorporation was observed for mucosal addressin cell adhesion molecule 1. The utility of clinical pulse-chase studies to investigate protein turnover can be extended by serial immunoaffinity enrichment of target proteins. Turnover analysis from serum and subsequently from remaining supernatants provided analytical sensitivity and reproducibility for multiple human target proteins in the same sample set, irrespective of the order of analysis. © 2017 American Association for Clinical Chemistry.

  11. Control of the Protein Turnover Rates in Lemna minor

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    Trewavas, A.

    1972-01-01

    The control of protein turnover in Lemna minor has been examined using a method described in the previous paper for determining the rate constants of synthesis and degradation of protein. If Lemna is placed on water, there is a reduction in the rate constants of synthesis of protein and an increase (3- to 6-fold) in the rate constant of degradation. The net effect is a loss of protein from the tissue. Omission of nitrate, phosphate, sulfate, magnesium, or calcium results in increases in the rate constant of degradation of protein. An unusual dual effect of benzyladenine on the turnover constants has been observed. Treatment of Lemna grown on sucrose-mineral salts with benzyladenine results in alterations only in the rate constant of synthesis. Treatment of Lemna grown on water with benzyladenine alters only the rate constant of degradation. Abscisic acid on the other hand alters both rate constants of synthesis and degradation of protein together. Inclusion of growth-inhibiting amino acids in the medium results in a reduction in the rate constants of synthesis and increases in the rate constant of degradation of protein. It is concluded that the rate of turnover of protein in Lemna is very dependent on the composition of the growth medium. Conditions which reduce growth rates also reduce the rates of synthesis of protein and increase those of degradation. PMID:16657895

  12. Methyl group turnover on methyl-accepting chemotaxis proteins during chemotaxis by Bacillus subtilis

    International Nuclear Information System (INIS)

    Thoelke, M.S.; Casper, J.M.; Ordal, G.W.

    1990-01-01

    The addition of attractant to Bacillus subtilis briefly exposed to radioactive methionine causes an increase of labeling of the methyl-accepting chemotaxis proteins. The addition of attractant to cells radiolabeled for longer times shows no change in the extent of methylation. Therefore, the increase in labeling for the briefly labeled cells is due to an increased turnover of methyl groups caused by attractant. All amino acids gave enhanced turnover. This turnover lasted for a prolonged time, probably spanning the period of smooth swimming caused by the attractant addition. Repellent did not affect the turnover when added alone or simultaneously with attractant. Thus, for amino acid attractants, the turnover is probably the excitatory signal, which is seen to extend long into or throughout the adaptation period, not just at the start of it

  13. Protein turnover and 3-methylhistidine excretion in non-pregnant, pregnant and gestational diabetic women

    International Nuclear Information System (INIS)

    Fitch, W.L.; King, J.C.

    1986-01-01

    Protein turnover was studied in nine non-pregnant (NP) women, eight pregnant (P) and two gestational diabetic (GDM) women. Whole body protein turnover, synthesis and catabolism rates were measured using a single oral dose of 15 N-glycine followed by measurement of enrichment of urinary ammonia. Urinary 3-methylhistidine (3MH) excretion was measured for three consecutive days, including the day of the protein turnover study. Whole body protein turnover and synthesis rates did not differ between the P and NP women, although the synthesis rates tended to be higher in the P group. Gestational diabetic women appeared to have considerably higher rates of both turnover and synthesis. Pregnant women excreted significantly more urinary 3MH than did non-pregnant women. GDM women appeared to have lower 3MH excretion than the P women. Correlation between 3MH excretion and protein turnover rates was nearly significant (p = .06) in the NP women, but was poorly correlated (p = .43) in the P women, suggesting that muscles may be a less important site of whole body protein turnover in pregnancy than in the non-pregnant state

  14. Metabolic Turnover of Synaptic Proteins: Kinetics, Interdependencies and Implications for Synaptic Maintenance

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    Cohen, Laurie D.; Zuchman, Rina; Sorokina, Oksana; Müller, Anke; Dieterich, Daniela C.; Armstrong, J. Douglas; Ziv, Tamar; Ziv, Noam E.

    2013-01-01

    Chemical synapses contain multitudes of proteins, which in common with all proteins, have finite lifetimes and therefore need to be continuously replaced. Given the huge numbers of synaptic connections typical neurons form, the demand to maintain the protein contents of these connections might be expected to place considerable metabolic demands on each neuron. Moreover, synaptic proteostasis might differ according to distance from global protein synthesis sites, the availability of distributed protein synthesis facilities, trafficking rates and synaptic protein dynamics. To date, the turnover kinetics of synaptic proteins have not been studied or analyzed systematically, and thus metabolic demands or the aforementioned relationships remain largely unknown. In the current study we used dynamic Stable Isotope Labeling with Amino acids in Cell culture (SILAC), mass spectrometry (MS), Fluorescent Non–Canonical Amino acid Tagging (FUNCAT), quantitative immunohistochemistry and bioinformatics to systematically measure the metabolic half-lives of hundreds of synaptic proteins, examine how these depend on their pre/postsynaptic affiliation or their association with particular molecular complexes, and assess the metabolic load of synaptic proteostasis. We found that nearly all synaptic proteins identified here exhibited half-lifetimes in the range of 2–5 days. Unexpectedly, metabolic turnover rates were not significantly different for presynaptic and postsynaptic proteins, or for proteins for which mRNAs are consistently found in dendrites. Some functionally or structurally related proteins exhibited very similar turnover rates, indicating that their biogenesis and degradation might be coupled, a possibility further supported by bioinformatics-based analyses. The relatively low turnover rates measured here (∼0.7% of synaptic protein content per hour) are in good agreement with imaging-based studies of synaptic protein trafficking, yet indicate that the metabolic load

  15. Turnover of whole body proteins and myofibrillar proteins in middle-aged active men

    International Nuclear Information System (INIS)

    Zackin, M.; Meredith, C.; Frontera, W.; Evans, W.

    1986-01-01

    Endurance-trained older men have a higher proportion of lean tissue and greater muscle cell oxidative capacity, reversing age-related trends and suggesting major changes in protein metabolism. In this study, protein turnover was determined in 6 middle-aged (52+/-1 yr) men who were well trained (VO 2 max 55.2+/-5.0 ml O 2 /kg.min) and lean (body fat 18.9+/-2.8%, muscle mass 36.6+/-0.6%). The maintained habitual exercise while consuming 0.6, 0.9 or 1.2 g protein/kg.day for 10-day periods. N flux was measured from 15 N in urea after oral 15 N-glycine administration. Myofibrillar protein breakdown was estimated from urinary 3-methyl-histidine. Dietary protein had no effect on turnover rates, even when N balance was negative. Whole body protein synthesis was 3.60+/-0.12 g/kg.day and breakdown was 3.40+/-0.14 g/kg.day for all N intakes. Whole body protein flux, synthesis and breakdown were similar to values reported for sedentary young (SY) or sedentary old (SO) men on comparable diets. 3-me-his (3.67+/-0.14 μmol/kg.day) was similar to values reported for SY but higher (p<0.01) than for SO. Myofibrillar protein breakdown per unit muscle mass (185+/-7 μmol 3-me-his/g creatinine) was higher (p<0.01) than for SY or SO. In active middle-aged men, myofibrillar proteins may account for a greater proportion of whole body protein turnover, despite an age-related reduction in muscle mass

  16. Effect of thyroid hormone on the protein turnover rate of mouse pancreas

    International Nuclear Information System (INIS)

    He Xinjun; Zhou Hui; Wang Shizhen; Zhou Zhonming; Li Liangxue; Wei Huaiwei; Sun Xiaomiao; Wang Yanli

    1986-01-01

    The effects of thyroid hormone on the protein turnover of pancreas in mice were studied using labelled amino acid incorporation, double isotopic and labelled protein decay methods. After injection of L-thyroxine (100 μ g/mouse) for 5 days, the amino acid incorporation into pancreatic proteins of mice was profoundly decreased, the ratio of 3 H/ 14 C in labelled proteins and the fractional turnover rate of pancreatic proteins were also decreased, the protein half-lives being consequently prolonged. These findings suggest that large doses of thyroid hormone may reduce the trunover rate of pancreatic proteins, by inhibiting not only the synthesis but also the degradation

  17. Feasibility of protein turnover studies in prototroph Saccharomyces cerevisiae strains.

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    Martin-Perez, Miguel; Villén, Judit

    2015-04-07

    Quantitative proteomics studies of yeast that use metabolic labeling with amino acids rely on auxotrophic mutations of one or more genes on the amino acid biosynthesis pathways. These mutations affect yeast metabolism and preclude the study of some biological processes. Overcoming this limitation, it has recently been described that proteins in a yeast prototrophic strain can also be metabolically labeled with heavy amino acids. However, the temporal profiles of label incorporation under the different phases of the prototroph's growth have not been examined. Labeling trajectories are important in the study of protein turnover and dynamics, in which label incorporation into proteins is monitored across many time points. Here we monitored protein labeling trajectories for 48 h after a pulse with heavy lysine in a yeast prototrophic strain and compared them with those of a lysine auxotrophic yeast. Labeling was successful in prototroph yeast during exponential growth phase but not in stationary phase. Furthermore, we were able to determine the half-lives of more than 1700 proteins during exponential phase of growth with high accuracy and reproducibility. We found a median half-life of 2 h in both strains, which corresponds with the cellular doubling time. Nucleolar and ribosomal proteins showed short half-lives, whereas mitochondrial proteins and other energy production enzymes presented longer half-lives. Except for some proteins involved in lysine biosynthesis, we observed a high correlation in protein half-lives between prototroph and auxotroph strains. Overall, our results demonstrate the feasibility of using prototrophs for proteomic turnover studies and provide a reliable data set of protein half-lives in exponentially growing yeast.

  18. Growth rate correlates negatively with protein turnover in Arabidopsis accessions.

    Science.gov (United States)

    Ishihara, Hirofumi; Moraes, Thiago Alexandre; Pyl, Eva-Theresa; Schulze, Waltraud X; Obata, Toshihiro; Scheffel, André; Fernie, Alisdair R; Sulpice, Ronan; Stitt, Mark

    2017-08-01

    Previous studies with Arabidopsis accessions revealed that biomass correlates negatively to dusk starch content and total protein, and positively to the maximum activities of enzymes in photosynthesis. We hypothesized that large accessions have lower ribosome abundance and lower rates of protein synthesis, and that this is compensated by lower rates of protein degradation. This would increase growth efficiency and allow more investment in photosynthetic machinery. We analysed ribosome abundance and polysome loading in 19 accessions, modelled the rates of protein synthesis and compared them with the observed rate of growth. Large accessions contained less ribosomes than small accessions, due mainly to cytosolic ribosome abundance falling at night in large accessions. The modelled rates of protein synthesis resembled those required for growth in large accessions, but were up to 30% in excess in small accessions. We then employed 13 CO 2 pulse-chase labelling to measure the rates of protein synthesis and degradation in 13 accessions. Small accessions had a slightly higher rate of protein synthesis and much higher rates of protein degradation than large accessions. Protein turnover was negligible in large accessions but equivalent to up to 30% of synthesised protein day -1 in small accessions. We discuss to what extent the decrease in growth in small accessions can be quantitatively explained by known costs of protein turnover and what factors may lead to the altered diurnal dynamics and increase of ribosome abundance in small accessions, and propose that there is a trade-off between protein turnover and maximisation of growth rate. © 2017 The Authors The Plant Journal © 2017 John Wiley & Sons Ltd.

  19. FOXO/DAF-16 Activation Slows Down Turnover of the Majority of Proteins in C. elegans

    Directory of Open Access Journals (Sweden)

    Ineke Dhondt

    2016-09-01

    Full Text Available Most aging hypotheses assume the accumulation of damage, resulting in gradual physiological decline and, ultimately, death. Avoiding protein damage accumulation by enhanced turnover should slow down the aging process and extend the lifespan. However, lowering translational efficiency extends rather than shortens the lifespan in C. elegans. We studied turnover of individual proteins in the long-lived daf-2 mutant by combining SILeNCe (stable isotope labeling by nitrogen in Caenorhabditis elegans and mass spectrometry. Intriguingly, the majority of proteins displayed prolonged half-lives in daf-2, whereas others remained unchanged, signifying that longevity is not supported by high protein turnover. This slowdown was most prominent for translation-related and mitochondrial proteins. In contrast, the high turnover of lysosomal hydrolases and very low turnover of cytoskeletal proteins remained largely unchanged. The slowdown of protein dynamics and decreased abundance of the translational machinery may point to the importance of anabolic attenuation in lifespan extension, as suggested by the hyperfunction theory.

  20. FOXO/DAF-16 Activation Slows Down Turnover of the Majority of Proteins in C. elegans.

    Science.gov (United States)

    Dhondt, Ineke; Petyuk, Vladislav A; Cai, Huaihan; Vandemeulebroucke, Lieselot; Vierstraete, Andy; Smith, Richard D; Depuydt, Geert; Braeckman, Bart P

    2016-09-13

    Most aging hypotheses assume the accumulation of damage, resulting in gradual physiological decline and, ultimately, death. Avoiding protein damage accumulation by enhanced turnover should slow down the aging process and extend the lifespan. However, lowering translational efficiency extends rather than shortens the lifespan in C. elegans. We studied turnover of individual proteins in the long-lived daf-2 mutant by combining SILeNCe (stable isotope labeling by nitrogen in Caenorhabditiselegans) and mass spectrometry. Intriguingly, the majority of proteins displayed prolonged half-lives in daf-2, whereas others remained unchanged, signifying that longevity is not supported by high protein turnover. This slowdown was most prominent for translation-related and mitochondrial proteins. In contrast, the high turnover of lysosomal hydrolases and very low turnover of cytoskeletal proteins remained largely unchanged. The slowdown of protein dynamics and decreased abundance of the translational machinery may point to the importance of anabolic attenuation in lifespan extension, as suggested by the hyperfunction theory. Copyright © 2016 The Author(s). Published by Elsevier Inc. All rights reserved.

  1. Effect of alcohol consumption on whole-body protein turnover in healthy adults.

    Science.gov (United States)

    Wutzke, Klaus D; Krentz, Helga; Bruns, Gerrit

    2011-03-01

    The aim of the study was to investigate the whole-body protein turnover, either before or after continuous, moderate ethanol-induced oxidative stress by red wine consumption over a relatively short period in healthy volunteers. Ten healthy adults received an individual regular diet over 20 days. After 10 days, the subjects consumed 0.4 ml ethanol kg(-1) day(-1) as red wine together with dinner over a 10-day period. After 8 and 18 days, respectively, a (15)N-labelled yeast protein was administered in a dosage of 4.2 mg kg(-1) body weight. Urine and faeces were collected over 48 h, respectively. The (15)N-enrichment was measured by isotope ratio mass spectrometry, whereas the protein flux rates were calculated by a three-compartment model. The whole-body protein turnover without/with red wine consumption amounted to 3.73±0.6 and 3.49±0.6 g kg(-1) day(-1) (not significant), respectively. Moderate alcohol consumption does not induce significant short-term changes in the whole-body protein turnover of healthy adults.

  2. Increased Protein Stability and Decreased Protein Turnover in the Caenorhabditis elegans Ins/IGF-1 daf-2 Mutant.

    Science.gov (United States)

    Depuydt, Geert; Shanmugam, Nilesh; Rasulova, Madina; Dhondt, Ineke; Braeckman, Bart P

    2016-12-01

    In Caenorhabditis elegans, cellular proteostasis is likely essential for longevity. Autophagy has been shown to be essential for lifespan extension of daf-2 insulin/IGF mutants. Therefore, it can be hypothesized that daf-2 mutants achieve this phenotype by increasing protein turnover. However, such a mechanism would exert a substantial energy cost. By using classical 35 S pulse-chase labeling, we observed that protein synthesis and degradation rates are decreased in young adults of the daf-2 insulin/IGF mutants. Although reduction of protein turnover may be energetically favorable, it may lead to accumulation and aggregation of damaged proteins. As this has been shown not to be the case in daf-2 mutants, another mechanism must exist to maintain proteostasis in this strain. We observed that proteins isolated from daf-2 mutants are more soluble in acidic conditions due to increased levels of trehalose. This suggests that trehalose may decrease the potential for protein aggregation and increases proteostasis in the daf-2 mutants. We postulate that daf-2 mutants save energy by decreasing protein turnover rates and instead stabilize their proteome by trehalose. © The Author 2016. Published by Oxford University Press on behalf of The Gerontological Society of America.

  3. Analytical errors in measuring radioactivity in cell proteins and their effect on estimates of protein turnover in L cells

    International Nuclear Information System (INIS)

    Silverman, J.A.; Mehta, J.; Brocher, S.; Amenta, J.S.

    1985-01-01

    Previous studies on protein turnover in 3 H-labelled L-cell cultures have shown recovery of total 3 H at the end of a three-day experiment to be always significantly in excess of the 3 H recovered at the beginning of the experiment. A number of possible sources for this error in measuring radioactivity in cell proteins has been reviewed. 3 H-labelled proteins, when dissolved in NaOH and counted for radioactivity in a liquid-scintillation spectrometer, showed losses of 30-40% of the radioactivity; neither external or internal standardization compensated for this loss. Hydrolysis of these proteins with either Pronase or concentrated HCl significantly increased the measured radioactivity. In addition, 5-10% of the cell protein is left on the plastic culture dish when cells are recovered in phosphate-buffered saline. Furthermore, this surface-adherent protein, after pulse labelling, contains proteins of high radioactivity that turn over rapidly and make a major contribution to the accumulating radioactivity in the medium. These combined errors can account for up to 60% of the total radioactivity in the cell culture. Similar analytical errors have been found in studies of other cell cultures. The effect of these analytical errors on estimates of protein turnover in cell cultures is discussed. (author)

  4. Amino acid metabolism and whole-body protein turnover in lambs ...

    African Journals Online (AJOL)

    The effect of protein supplementation of a wheat straw diet on the metabolism of lysine, leucine, methionine and urea, and on whole-body protein turnover rate was investigated in lambs. The metabolism of lysine and leucine is reported elsewhere (Cronje et aI., 1992); in this paper methionine metabolism is discussed, and ...

  5. Acute moderate elevation of TNF-{alpha} does not affect systemic and skeletal muscle protein turnover in healthy humans

    DEFF Research Database (Denmark)

    Petersen, Anne Marie; Plomgaard, Peter; Fischer, Christian P

    2009-01-01

    -alpha infusion (rhTNF-alpha). We hypothesize that TNF-alpha increases human muscle protein breakdown and/or inhibit synthesis. Subjects and Methods: Using a randomized controlled, crossover design post-absorptive healthy young males (n=8) were studied 2 hours under basal conditions followed by 4 hours infusion...... with the phenylalanine 3-compartment model showed similar muscle synthesis, breakdown and net muscle degradation after 2 hours basal and after 4 hours Control or rhTNF-alpha infusion. Conclusion: This study is the first to show in humans that TNF-alpha does not affect systemic and skeletal muscle protein turnover, when......Context: Skeletal muscle wasting has been associated with elevations in circulating inflammatory cytokines, in particular TNF-alpha. Objective: In this study, we investigated whether TNF-alpha affects human systemic and skeletal muscle protein turnover, via a 4 hours recombinant human TNF...

  6. Determination of protein turnover parameters in athletes using 15N tracers

    International Nuclear Information System (INIS)

    Krumbiegel, P.; Kuehne, K.; Faust, H.; Bornhak, H.; Junghans, P.; Zerbes, H.

    1985-01-01

    In 2 adolescent female athletes engaged in technical-acrobatic sports the influence of a high protein diet on the protein turnover rate under training conditions was investigated by means of 15 N-glycine. Protein synthesis was significantly increased, whereas the utilization of nutritive nitrogen was decreased as expected. The 15 N tracer technique is well suited to determine the protein requirements under special training conditions

  7. Impact of transamination reactions and protein turnover on labeling dynamics in C-13-labeling experiments

    DEFF Research Database (Denmark)

    Grotkjær, Thomas; Åkesson, M.; Christensen, Bjarke

    2004-01-01

    A dynamic model describing carbon atom transitions in the central metabolism of Saccharomyces cerevisiae is used to investigate the influence of transamination reactions and protein turnover on the transient behavior of C-13-labeling chemostat experiments. The simulations performed suggest...... that carbon exchange due to transamination and protein turnover can significantly increase the required time needed for metabolites in the TCA cycle to reach isotopic steady state, which is in agreement with published experimental observations. On the other hand, transamination and protein turnover will speed...... behavior until after three residence times. These observations suggest that greater caution should be used while also pointing to new opportunities in the design and interpretation of C-13-labeling experiments....

  8. Dystropathology Increases Energy Expenditure and Protein Turnover in the Mdx Mouse Model of Duchenne Muscular Dystrophy

    Science.gov (United States)

    Radley-Crabb, Hannah G.; Marini, Juan C.; Sosa, Horacio A.; Castillo, Liliana I.; Grounds, Miranda D.; Fiorotto, Marta L.

    2014-01-01

    The skeletal muscles in Duchenne muscular dystrophy and the mdx mouse model lack functional dystrophin and undergo repeated bouts of necrosis, regeneration, and growth. These processes have a high metabolic cost. However, the consequences for whole body energy and protein metabolism, and on the dietary requirements for these macronutrients at different stages of the disease, are not well-understood. This study used juvenile (4- to 5- wk-old) and adult (12- to 14-wk-old) male dystrophic C57BL/10ScSn-mdx/J and age-matched C57BL/10ScSn/J control male mice to measure total and resting energy expenditure, food intake, spontaneous activity, body composition, whole body protein turnover, and muscle protein synthesis rates. In juvenile mdx mice that have extensive muscle damage, energy expenditure, muscle protein synthesis, and whole body protein turnover rates were higher than in age-matched controls. Adaptations in food intake and decreased activity were insufficient to meet the increased energy and protein needs of juvenile mdx mice and resulted in stunted growth. In (non-growing) adult mdx mice with less severe dystropathology, energy expenditure, muscle protein synthesis, and whole body protein turnover rates were also higher than in age-matched controls. Food intake was sufficient to meet their protein and energy needs, but insufficient to result in fat deposition. These data show that dystropathology impacts the protein and energy needs of mdx mice and that tailored dietary interventions are necessary to redress this imbalance. If not met, the resultant imbalance blunts growth, and may limit the benefits of therapies designed to protect and repair dystrophic muscles. PMID:24586653

  9. Interleukin-6 markedly decreases skeletal muscle protein turnover and increases nonmuscle amino acid utilization in healthy individuals

    DEFF Research Database (Denmark)

    van Hall, Gerrit; Steensberg, Adam; Fischer, Christian

    2008-01-01

    CONTEXT: IL-6 is a key modulator of immune function and suggested to be involved in skeletal muscle wasting as seen in sepsis. OBJECTIVE: Our objective was to determine the role of IL-6 in human in vivo systemic and skeletal muscle amino acid metabolism and protein turnover. SUBJECTS AND METHODS...... synthesis was more suppressed than breakdown, causing a small increase in net muscle protein breakdown. Furthermore, rhIL-6 decreased arterial amino acid concentration with 20-40%, despite the increase net release from muscle. CONCLUSIONS: We demonstrated that IL-6 profoundly alters amino acid turnover....... A substantial decrease in plasma amino acids was observed with a concomitant 50% decrease in muscle protein turnover, however, modest increase in net muscle degradation. We hypothesize that the profound reduction in muscle protein turnover and modest increase in net degradation are primarily caused...

  10. Evolutionary Turnover of Kinetochore Proteins: A Ship of Theseus?

    Science.gov (United States)

    Drinnenberg, Ines A; Henikoff, Steven; Malik, Harmit S

    2016-07-01

    The kinetochore is a multiprotein complex that mediates the attachment of a eukaryotic chromosome to the mitotic spindle. The protein composition of kinetochores is similar across species as divergent as yeast and human. However, recent findings have revealed an unexpected degree of compositional diversity in kinetochores. For example, kinetochore proteins that are essential in some species have been lost in others, whereas new kinetochore proteins have emerged in other lineages. Even in lineages with similar kinetochore composition, individual kinetochore proteins have functionally diverged to acquire either essential or redundant roles. Thus, despite functional conservation, the repertoire of kinetochore proteins has undergone recurrent evolutionary turnover. Copyright © 2016 Elsevier Ltd. All rights reserved.

  11. Hepatitis C Virus Core Protein Decreases Lipid Droplet Turnover

    Science.gov (United States)

    Harris, Charles; Herker, Eva; Farese, Robert V.; Ott, Melanie

    2011-01-01

    Steatosis is a frequent complication of hepatitis C virus infection. In mice, this condition is recapitulated by the expression of a single viral protein, the nucleocapsid core. Core localizes to the surface of lipid droplets (LDs) in infected liver cells through a process dependent on host diacylglycerol acyltransferase 1 (DGAT1), an enzyme that synthesizes triglycerides in the endoplasmic reticulum. Whether DGAT1 also plays a role in core-induced steatosis is uncertain. Here, we show that mouse embryonic fibroblasts isolated from DGAT1−/− mice are protected from core-induced steatosis, as are livers of DGAT1−/− mice expressing core, demonstrating that the steatosis is DGAT1-dependent. Surprisingly, core expression did not increase DGAT1 activity or triglyceride synthesis, thus excluding the possibility that core activates DGAT1 to cause steatosis. Instead, we find that DGAT1-dependent localization of core to LDs is a prerequisite for the steatogenic properties of the core. Using biochemical and immunofluorescence microscopy techniques, we show that the turnover of lipids in core-coated droplets is decreased, providing a physiological mechanism for core-induced steatosis. Our results support a bipartite model in which core first requires DGAT1 to gain access to LDs, and then LD-localized core interferes with triglyceride turnover, thus stabilizing lipid droplets and leading to steatosis. PMID:21984835

  12. In vivo measurement of myocardial protein turnover using an indicator dilution technique

    International Nuclear Information System (INIS)

    Revkin, J.H.; Young, L.H.; Stirewalt, W.S.; Dahl, D.M.; Gelfand, R.A.; Zaret, B.L.; Barrett, E.J.

    1990-01-01

    We applied a nondestructive tracer technique, previously developed for measuring skeletal muscle protein turnover, to the measurement of myocardial protein turnover in vivo. During a continuous infusion of L-[ring-2,6-3H]phenylalanine to anesthetized, overnight-fasted dogs, we measured the uptake of radiolabeled phenylalanine from plasma and the release of unlabeled phenylalanine from myocardial proteolysis using arterial and coronary sinus catheterization and analytic methods previously applied to skeletal muscle. Using these measurements, together with a model of myocardial protein synthesis that assumes rapid equilibration of tracer specific activity between myocardial phenylalanyl-tRNA and circulating phenylalanine, we estimated the rates of heart protein synthesis and degradation. The rate of heart protein synthesis was also estimated directly from the incorporation of labeled phenylalanine into tissue protein. The use of [3H]phenylalanine was compared with L-[1-14C]leucine in the measurement of heart protein turnover in dogs given simultaneous infusion of both tracers. Leucine uptake and release by the myocardium exceeded that of phenylalanine by 3.1 +/- 0.4- and 1.7 +/- 0.3-fold, respectively, consistent with leucine's 2.4-fold greater abundance in heart protein and its metabolism via other pathways. Phenylalanine is the preferred tracer for use with this method because of its limited metabolic fate in muscle. One theoretical limitation to the method, slow equilibration of circulating labeled phenylalanine with myocardial phenylalanyl-tRNA, was resolved by comparison of these specific activities after a 30-minute infusion of labeled phenylalanine in the rat. A second, empirical limitation involves precision in the measurement of the small decrements in phenylalanine specific activity that occur with each pass of blood through the coronary circulation

  13. Whole-body protein turnover of a carnivore, Felis silvestris catus.

    Science.gov (United States)

    Russell, K; Lobley, G E; Millward, D J

    2003-01-01

    The cat (Felis silvestris catus) has a higher dietary protein requirement than omnivores and herbivores, thought to be due to metabolic inflexibility. An aspect of metabolic flexibility was examined with studies of whole-body protein turnover at two levels of dietary protein energy, moderate protein (MP; 20 %) and high protein (HP; 70 %), in five adult cats in a crossover design. Following a 14 d pre-feed period, a single intravenous dose of [15N]glycine was administered and cumulative excretion of the isotope in urine and faeces determined over 48 h. N flux increased (Pwork is required to determine exactly why cats have such a high protein requirement.

  14. FOXO/DAF-16 Activation Slows Down Turnover of the Majority of Proteins in C. elegans

    Energy Technology Data Exchange (ETDEWEB)

    Dhondt, Ineke; Petyuk, Vladislav A.; Cai, Huaihan; Vandemeulebroucke, Lieselot; Vierstraete, Andy; Smith, Richard D.; Depuydt, Geert; Braeckman, Bart P.

    2016-09-01

    Cellular protein quality can be maintained by proteolytic elimination of damaged proteins and replacing them with newly synthesized copies, a process called protein turnover (Ward, 2000). Protein turnover rates have been estimated using SILAC (stable isotope labeling by amino acids in cell culture) in prokaryotes and eukaryotes. The last decade has witnessed a growing interest in the analysis of whole-organism proteome dynamics in metazoans using the same approach (Claydon and Beynon, 2012). In recent work, SILAC was applied to monitor protein synthesis throughout life in adult Caenorhabditis elegans (Vukoti et al., 2015) and to investigate food intake (Gomez-Amaro et al., 2015

  15. Protein turnover in acid maltase deficiency before and after treatment with a high protein diet.

    OpenAIRE

    Umpleby, A M; Wiles, C M; Trend, P S; Scobie, I N; Macleod, A F; Spencer, G T; Sonksen, P H

    1987-01-01

    A patient with acid maltase deficiency was treated with a high protein diet for 7 months. Protein turnover expressed in terms of lean body mass was shown to be increased in this patient before the diet but was markedly reduced following the diet. The patient improved clinically whilst on the diet both subjectively and in terms of mobility, breathing and reduced peripheral cyanosis at rest.

  16. Turnover-dependent inactivation of the nitrogenase MoFe-protein at high pH.

    Science.gov (United States)

    Yang, Kun-Yun; Haynes, Chad A; Spatzal, Thomas; Rees, Douglas C; Howard, James B

    2014-01-21

    Proton uptake accompanies the reduction of all known substrates by nitrogenase. As a consequence, a higher pH should limit the availability of protons as a substrate essential for turnover, thereby increasing the proportion of more highly reduced forms of the enzyme for further study. The utility of the high-pH approach would appear to be problematic in view of the observation reported by Pham and Burgess [(1993) Biochemistry 32, 13725-13731] that the MoFe-protein undergoes irreversible protein denaturation above pH 8.65. In contrast, we found by both enzyme activity and crystallographic analyses that the MoFe-protein is stable when incubated at pH 9.5. We did observe, however, that at higher pHs and under turnover conditions, the MoFe-protein is slowly inactivated. While a normal, albeit low, level of substrate reduction occurs under these conditions, the MoFe-protein undergoes a complex transformation; initially, the enzyme is reversibly inhibited for substrate reduction at pH 9.5, yet in a second, slower process, the MoFe-protein becomes irreversibly inactivated as measured by substrate reduction activity at the optimal pH of 7.8. The final inactivated MoFe-protein has an increased hydrodynamic radius compared to that of the native MoFe-protein, yet it has a full complement of iron and molybdenum. Significantly, the modified MoFe-protein retains the ability to specifically interact with its nitrogenase partner, the Fe-protein, as judged by the support of ATP hydrolysis and by formation of a tight complex with the Fe-protein in the presence of ATP and aluminum fluoride. The turnover-dependent inactivation coupled to conformational change suggests a mechanism-based transformation that may provide a new probe of nitrogenase catalysis.

  17. Studies on protein turnover and energy expenditure in chronically undernourished adults during stress of infection

    International Nuclear Information System (INIS)

    Kurpad, A.V.; Shetty, P.S.; Reeds, P.J.

    1994-01-01

    Chronic undernutrition in man leads to adaptive responses which could reduce the requirements for dietary energy and protein. It is also possible that these adaptive responses, which are economical in nature, could lead to a decreased capacity for combating stress. Undernourished people are more susceptible to infections, and during these stresses, show different patterns of protein and energy metabolism from well-nourished subjects. Animal models have clearly shown a diminished response to tissue injury, in terms of the anabolic acute phase response. It is proposed to study the effect of prior nutritional status on the degree to which an infective stress stimulates the acute phase protein synthesis by the liver. In addition, the supply of amino acids to the liver in conditions of stress could come from the breakdown of body tissue proteins, particularly muscle. It is intended to study muscle protein turnover by the use of 13 C-leucine in undernourished subjects under conditions of stress. Since whole body protein turnover can be measured by two methods, using 15 N-glycine and 13 C-leucine, a comparison of these two methods will initially be made in chronically undernourished subjects. It is also intended to study daily energy expenditure in the subject by an isotopic method, i.e. the appearance of 13 CO 2 in the breath after the administration of 13 C-bicarbonate. (author). 8 refs

  18. Peptide Level Turnover Measurements Enable the Study of Proteoform Dynamics.

    Science.gov (United States)

    Zecha, Jana; Meng, Chen; Zolg, Daniel Paul; Samaras, Patroklos; Wilhelm, Mathias; Kuster, Bernhard

    2018-05-01

    The coordination of protein synthesis and degradation regulating protein abundance is a fundamental process in cellular homeostasis. Today, mass spectrometry-based technologies allow determination of endogenous protein turnover on a proteome-wide scale. However, standard dynamic SILAC (Stable Isotope Labeling in Cell Culture) approaches can suffer from missing data across pulse time-points limiting the accuracy of such analysis. This issue is of particular relevance when studying protein stability at the level of proteoforms because often only single peptides distinguish between different protein products of the same gene. To address this shortcoming, we evaluated the merits of combining dynamic SILAC and tandem mass tag (TMT)-labeling of ten pulse time-points in a single experiment. Although the comparison to the standard dynamic SILAC method showed a high concordance of protein turnover rates, the pulsed SILAC-TMT approach yielded more comprehensive data (6000 proteins on average) without missing values. Replicate analysis further established that the same reproducibility of turnover rate determination can be obtained for peptides and proteins facilitating proteoform resolved investigation of protein stability. We provide several examples of differentially turned over splice variants and show that post-translational modifications can affect cellular protein half-lives. For example, N-terminally processed peptides exhibited both faster and slower turnover behavior compared with other peptides of the same protein. In addition, the suspected proteolytic processing of the fusion protein FAU was substantiated by measuring vastly different stabilities of the cleavage products. Furthermore, differential peptide turnover suggested a previously unknown mechanism of activity regulation by post-translational destabilization of cathepsin D as well as the DNA helicase BLM. Finally, our comprehensive data set facilitated a detailed evaluation of the impact of protein

  19. Whole-body protein turnover response to short-term high-protein diets during weight loss: a randomized controlled trial

    Science.gov (United States)

    Objective: Determine whole-body protein turnover responses to high protein diets during weight loss. Design: Thirty-nine adults (age, 21 ± 1 yr; VO2peak, 48 ± 1 ml'kg-1'min-1; body mass index, 25 ± 1 kg•m2) were randomized to diets providing protein at the recommend dietary allowance (RDA), 2X-RD...

  20. Effects of ractopamine and gender on protein turnover in skeletal ...

    African Journals Online (AJOL)

    Effects of the β-agonist, ractopamine-HCl (ractopamine), on skeletal muscle protein turnover were evaluated in 16 steers (512 kg) and 16 heifers (473 kg). Treatments were arranged in a 2 × 2 factorial design and included gender (steer vs. heifer) and ractopamine (0 or 200 mg/d). Steers were implanted with 120 mg ...

  1. USP21 regulates Hippo pathway activity by mediating MARK protein turnover

    DEFF Research Database (Denmark)

    Nguyen, Thanh Hung; Kugler, Jan-Michael; Loya, Anand Chainsukh

    2017-01-01

    observed in cancer and often correlates with worse survival. The activity and stability of Hippo pathway components, including YAP/TAZ, AMOT and LATS1/2, are regulated by ubiquitin-mediated protein degradation. Aberrant expression of ubiquitin ligase complexes that regulate the turnover of Hippo components...

  2. Cell viability and protein turnover in nongrowing Bacillus megaterium at sporulation suppressing temperature.

    Science.gov (United States)

    Kucerová, H; Strnadová, M; Ludvík, J; Chaloupka, J

    1999-01-01

    In Bacillus megaterium, a temperature that suppresses sporulation (43 degrees C) only slightly exceeds both the optimum growth temperature and the temperature still permitting sporulation (40-41 degrees C). Here we show that, when cells grown at 35 degrees C and transferred to a sporulation medium, were subjected to shifts between 35 degrees C and the sporulation suppressing temperature (SST, 43 degrees C), their development and proteolytic activities were deeply affected. During the reversible sporulation phase that took place at 35 degrees C for 2-3 h (T2-T3), the cells developed forespores and their protein turnover was characterized by degradation of short-lived proteins and proteins made accessible to the proteolytic attack because of starvation. During the following irreversible sporulation phase refractile heat-resistant spores appeared at T4-T5. Protein turnover rate increased again after T2 and up to T8 60-70% prelabelled proteins were degraded. The SST suppressed sporulation at its beginning; at T3 no asymmetric septa were observed and the amount of heat-resistant spores at T8 was by 4-5 orders lower than at 35 degrees C. However, the cells remained viable and were able to sporulate when transferred to a lower temperature. Protein degradation was increased up to T3 but then its velocity sharply dropped and the amount of degraded protein at T8 corresponded to slightly more than one-half of that found at 35 degrees C. The cytoplasmic proteolytic activity was enhanced but the activity in the membrane fraction was decreased. When a temperature shift to SST was applied at the beginning of the irreversible sporulation phase (T2.5), the sporulation process was impaired. A portion of forespores lyzed, the others were able to complete their development but most spores were not heat-resistant and their coats showed defects. Protein degradation increased again because an effective proteolytic system was developed during the reversible sporulation phase but the

  3. Turnover of amyloid precursor protein family members determines their nuclear signaling capability.

    Science.gov (United States)

    Gersbacher, Manuel T; Goodger, Zoë V; Trutzel, Annette; Bundschuh, Diana; Nitsch, Roger M; Konietzko, Uwe

    2013-01-01

    The amyloid precursor protein (APP) as well as its homologues, APP-like protein 1 and 2 (APLP1 and APLP2), are cleaved by α-, β-, and γ-secretases, resulting in the release of their intracellular domains (ICDs). We have shown that the APP intracellular domain (AICD) is transported to the nucleus by Fe65 where they jointly bind the histone acetyltransferase Tip60 and localize to spherical nuclear complexes (AFT complexes), which are thought to be sites of transcription. We have now analyzed the subcellular localization and turnover of the APP family members. Similarly to AICD, the ICD of APLP2 localizes to spherical nuclear complexes together with Fe65 and Tip60. In contrast, the ICD of APLP1, despite binding to Fe65, does not translocate to the nucleus. In addition, APLP1 predominantly localizes to the plasma membrane, whereas APP and APLP2 are detected in vesicular structures. APLP1 also demonstrates a much slower turnover of the full-length protein compared to APP and APLP2. We further show that the ICDs of all APP family members are degraded by the proteasome and that the N-terminal amino acids of ICDs determine ICD degradation rate. Together, our results suggest that different nuclear signaling capabilities of APP family members are due to different rates of full-length protein processing and ICD proteasomal degradation. Our results provide evidence in support of a common nuclear signaling function for APP and APLP2 that is absent in APLP1, but suggest that APLP1 has a regulatory role in the nuclear translocation of APP family ICDs due to the sequestration of Fe65.

  4. Distinct responses of protein turnover regulatory pathways in hypoxia- and semistarvation-induced muscle atrophy

    NARCIS (Netherlands)

    de Theije, Chiel C.; Langen, Ramon C. J.; Lamers, Wouter H.; Schols, Annemie M. W. J.; Köhler, S. Eleonore

    2013-01-01

    The balance of muscle protein synthesis and degradation determines skeletal muscle mass. We hypothesized that hypoxia-induced muscle atrophy and alterations in the regulation of muscle protein turnover include a hypoxia-specific component, in addition to the observed effects of reduction in food

  5. Protein turnover, amino acid requirements and recommendations for athletes and active populations

    Energy Technology Data Exchange (ETDEWEB)

    Poortmans, J.R.; Carpentier, A. [Laboratory for Biometry and Sport Nutrition, Faculty of Motor Sciences, Free University of Brussels, Brussels (Belgium); Pereira-Lancha, L.O. [Departamento de Nutrição, Instituto Vita, São Paulo, SP (Brazil); Lancha, A. Jr. [Laboratório de Nutrição Aplicada à Atividade Motora, Escola de Educação Física e Esporte, Universidade de São Paulo, São Paulo, SP (Brazil)

    2012-06-08

    Skeletal muscle is the major deposit of protein molecules. As for any cell or tissue, total muscle protein reflects a dynamic turnover between net protein synthesis and degradation. Noninvasive and invasive techniques have been applied to determine amino acid catabolism and muscle protein building at rest, during exercise and during the recovery period after a single experiment or training sessions. Stable isotopic tracers ({sup 13}C-lysine, {sup 15}N-glycine, {sup 2}H{sub 5}-phenylalanine) and arteriovenous differences have been used in studies of skeletal muscle and collagen tissues under resting and exercise conditions. There are different fractional synthesis rates in skeletal muscle and tendon tissues, but there is no major difference between collagen and myofibrillar protein synthesis. Strenuous exercise provokes increased proteolysis and decreased protein synthesis, the opposite occurring during the recovery period. Individuals who exercise respond differently when resistance and endurance types of contractions are compared. Endurance exercise induces a greater oxidative capacity (enzymes) compared to resistance exercise, which induces fiber hypertrophy (myofibrils). Nitrogen balance (difference between protein intake and protein degradation) for athletes is usually balanced when the intake of protein reaches 1.2 g·kg{sup −1}·day{sup −1} compared to 0.8 g·kg{sup −1}·day{sup −1} in resting individuals. Muscular activities promote a cascade of signals leading to the stimulation of eukaryotic initiation of myofibrillar protein synthesis. As suggested in several publications, a bolus of 15-20 g protein (from skimmed milk or whey proteins) and carbohydrate (± 30 g maltodextrine) drinks is needed immediately after stopping exercise to stimulate muscle protein and tendon collagen turnover within 1 h.

  6. Protein turnover, amino acid requirements and recommendations for athletes and active populations

    International Nuclear Information System (INIS)

    Poortmans, J.R.; Carpentier, A.; Pereira-Lancha, L.O.; Lancha, A. Jr.

    2012-01-01

    Skeletal muscle is the major deposit of protein molecules. As for any cell or tissue, total muscle protein reflects a dynamic turnover between net protein synthesis and degradation. Noninvasive and invasive techniques have been applied to determine amino acid catabolism and muscle protein building at rest, during exercise and during the recovery period after a single experiment or training sessions. Stable isotopic tracers ( 13 C-lysine, 15 N-glycine, 2 H 5 -phenylalanine) and arteriovenous differences have been used in studies of skeletal muscle and collagen tissues under resting and exercise conditions. There are different fractional synthesis rates in skeletal muscle and tendon tissues, but there is no major difference between collagen and myofibrillar protein synthesis. Strenuous exercise provokes increased proteolysis and decreased protein synthesis, the opposite occurring during the recovery period. Individuals who exercise respond differently when resistance and endurance types of contractions are compared. Endurance exercise induces a greater oxidative capacity (enzymes) compared to resistance exercise, which induces fiber hypertrophy (myofibrils). Nitrogen balance (difference between protein intake and protein degradation) for athletes is usually balanced when the intake of protein reaches 1.2 g·kg −1 ·day −1 compared to 0.8 g·kg −1 ·day −1 in resting individuals. Muscular activities promote a cascade of signals leading to the stimulation of eukaryotic initiation of myofibrillar protein synthesis. As suggested in several publications, a bolus of 15-20 g protein (from skimmed milk or whey proteins) and carbohydrate (± 30 g maltodextrine) drinks is needed immediately after stopping exercise to stimulate muscle protein and tendon collagen turnover within 1 h

  7. Protein turnover, amino acid requirements and recommendations for athletes and active populations

    Directory of Open Access Journals (Sweden)

    J.R. Poortmans

    2012-10-01

    Full Text Available Skeletal muscle is the major deposit of protein molecules. As for any cell or tissue, total muscle protein reflects a dynamic turnover between net protein synthesis and degradation. Noninvasive and invasive techniques have been applied to determine amino acid catabolism and muscle protein building at rest, during exercise and during the recovery period after a single experiment or training sessions. Stable isotopic tracers (13C-lysine, 15N-glycine, ²H5-phenylalanine and arteriovenous differences have been used in studies of skeletal muscle and collagen tissues under resting and exercise conditions. There are different fractional synthesis rates in skeletal muscle and tendon tissues, but there is no major difference between collagen and myofibrillar protein synthesis. Strenuous exercise provokes increased proteolysis and decreased protein synthesis, the opposite occurring during the recovery period. Individuals who exercise respond differently when resistance and endurance types of contractions are compared. Endurance exercise induces a greater oxidative capacity (enzymes compared to resistance exercise, which induces fiber hypertrophy (myofibrils. Nitrogen balance (difference between protein intake and protein degradation for athletes is usually balanced when the intake of protein reaches 1.2 g·kg-1·day-1 compared to 0.8 g·kg-1·day-1 in resting individuals. Muscular activities promote a cascade of signals leading to the stimulation of eukaryotic initiation of myofibrillar protein synthesis. As suggested in several publications, a bolus of 15-20 g protein (from skimmed milk or whey proteins and carbohydrate (± 30 g maltodextrine drinks is needed immediately after stopping exercise to stimulate muscle protein and tendon collagen turnover within 1 h.

  8. Resistance training reduces whole-body protein turnover and improves net protein retention in untrained young males.

    Science.gov (United States)

    Hartman, Joseph W; Moore, Daniel R; Phillips, Stuart M

    2006-10-01

    It is thought that resistance exercise results in an increased need for dietary protein; however, data also exists to support the opposite conclusion. The purpose of this study was to determine the impact of resistance exercise training on protein metabolism in novices with the hypothesis that resistance training would reduce protein turnover and improve whole-body protein retention. Healthy males (n = 8, 22 +/- 1 y, BMI = 25.3 +/- 1.8 kg.m(-2)) participated in a progressive whole-body split routine resistance-training program 5d/week for 12 weeks. Before (PRE) and after (POST) the training, oral [15N]-glycine ingestion was used to assess nitrogen flux (Q), protein synthesis (PS), protein breakdown (PB), and net protein balance (NPB = PS-PB). Macronutrient intake was controlled over a 5d period PRE and POST, while estimates of protein turnover and urinary nitrogen balance (N(bal) = N(in) - urine N(out)) were conducted. Bench press and leg press increased 40% and 50%, respectively (p training-induced increases in both NPB (PRE = 0.22 +/- 0.13 g.kg(-1).d(-1); POST = 0.54 +/- 0.08 g.kg(-1).d(-1)) and urinary nitrogen balance (PRE = 2.8 +/- 1.7 g N.d(-1); POST = 6.5 +/- 0.9 g N.d(-1)) were observed. A program of resistance training that induced significant muscle hypertrophy resulted in reductions of both whole-body PS and PB, but an improved NPB, which favoured the accretion of skeletal muscle protein. Urinary nitrogen balance increased after training. The reduction in PS and PB and a higher NPB in combination with an increased nitrogen balance after training suggest that dietary requirements for protein in novice resistance-trained athletes are not higher, but lower, after resistance training.

  9. Olfactory marker protein: turnover and transport in normal and regenerating neurons

    International Nuclear Information System (INIS)

    Kream, R.M.; Margolis, F.L.

    1984-01-01

    A 19,000-dalton acidic protein designated olfactory marker protein (OMP) is a cell-specific marker of mature olfactory chemosensory neurons. Intranasal irrigation of mouse olfactory epithelium with [ 35 S]methionine labeled OMP to high specific activity. Turnover and transport characteristics of 35 S-labeled OMP were compared to those of 35 S-labeled global cytosol protein in groups of young, adult, and Triton-treated adult mice. The latter contained primarily large numbers of regenerating olfactory neurons. In olfactory epithelium of young and Triton-treated mice, the specific activity of OMP was three times that of global cytosol protein, whereas in adults the two measures were equal. In all three groups, however, the rate of degradation of OMP was roughly equal to that of cytosol protein (T1/2 . 5 to 6 days). By contrast, differences in T1/2 for OMP decline in the bulb of adult, young, and Triton-treated adult mice were highly significant (T1/2's of 9.3, 6.1, and 4 to 5 days, respectively; p . 0.001). The specific activity of [35S]methionine incorporated in OMP exceeded that of the free amino acid 5-fold, indicating minimal precursor reutilization during the course of our experiments. Turnover data indicate that increased isotope incorporation into OMP in the epithelium is matched by an accelerated rate of degradation in the bulb. This may be correlated with the physiological state or developmental age of the primary neurons since in young and Triton-treated adult mice, rapidly maturing ''young'' olfactory neurons represent a larger proportion of the total population than in adults. Thus, OMP behaves as a typical, relatively slowly transported soluble protein (v . 2 to 4 mm/day, slow component b)

  10. Accelerated extracellular matrix turnover during exacerbations of COPD

    DEFF Research Database (Denmark)

    Sand, Jannie M B; Knox, Alan J; Lange, Peter

    2015-01-01

    progression. Extracellular matrix (ECM) turnover reflects activity in tissues and consequently assessment of ECM turnover may serve as biomarkers of disease activity. We hypothesized that the turnover of lung ECM proteins were altered during exacerbations of COPD. METHODS: 69 patients with COPD hospitalised...... of circulating fragments of structural proteins, which may serve as markers of disease activity. This suggests that patients with COPD have accelerated ECM turnover during exacerbations which may be related to disease progression....

  11. Cell cycle-specific UNG2 phosphorylations regulate protein turnover, activity and association with RPA

    DEFF Research Database (Denmark)

    Hagen, Lars; Kavli, Bodil; Sousa, Mirta M L

    2008-01-01

    -catalytic domain that confer distinct functional properties to UNG2. These are apparently generated by cyclin-dependent kinases through stepwise phosphorylation of S23, T60 and S64 in the cell cycle. Phosphorylation of S23 in late G1/early S confers increased association with replication protein A (RPA......) and replicating chromatin and markedly increases the catalytic turnover of UNG2. Conversely, progressive phosphorylation of T60 and S64 throughout S phase mediates reduced binding to RPA and flag UNG2 for breakdown in G2 by forming a cyclin E/c-myc-like phosphodegron. The enhanced catalytic turnover of UNG2 p-S23...

  12. Casein and soya-bean protein have different effects on whole body protein turnover at the same nitrogen balance

    DEFF Research Database (Denmark)

    Nielsen, K; Kondrup, J; Elsner, Petteri

    1994-01-01

    was recovered from urinary ammonia and urea during isotope steady state for measurement of protein synthesis and protein degradation. Compared with starvation the protein-free diet decreased N excretion by 75%, probably by increasing the rate of reutilization of amino acids from endogenous proteins for protein......The present study examined whether different proteins have different effects on whole-body protein turnover in adult rats. The rats were either starved, given a protein-free but energy-sufficient diet (1 MJ/kg body weight (BW) per d) or a diet containing intact casein, hydrolysed casein......, or hydrolysed soya-bean protein at a level of 9.1 g/kg BW per d. The diets, which were isoenergetic with the same carbohydrate: fat ratio, were given as a continuous intragastric infusion for at least 4 d. During the last 19 h 15N-glycine (a primed continuous infusion) was given intragastrically and 15N...

  13. Active Gating, Molecular Pumping, and Turnover Determination in Biomimetic Lipidic Cubic Mesophases with Reconstituted Membrane Proteins.

    Science.gov (United States)

    Speziale, Chiara; Zabara, Alexandru Florian; Drummond, Calum John; Mezzenga, Raffaele

    2017-11-28

    Understanding the mechanisms controlling molecular transport in bioinspired materials is a central topic in many branches of nanotechnology. In this work, we show that biomolecules of fundamental importance in biological processes, such as glucose, can be transported in an active, controlled, and selective manner across macroscopic lipidic cubic mesophases, by correctly reconstituting within them their corresponding membrane protein transporters, such as Staphylococcus epidermidis (GlcP Se ). Importantly, by duly exploiting the symporter properties of GlcP Se of coupled glucose/H + transport, the diffusion of glucose can further be tuned by independent physiological stimuli, such as parallel or antiparallel pH gradients, offering an important model to study molecular exchange processes in cellular machinery. We finally show that by measuring the transport properties of the lipidic mesophases with and without the GlcP Se membrane protein reconstituted within, it becomes possible to determine its intrinsic conductance. We generalize these findings to other membrane proteins from the antiporters family, such as the bacterial ClC exchanger from Escherichia coli (EcClC), providing a robust method for evaluating the turnover rate of the membrane proteins in general.

  14. Dynamic Proteomics Emphasizes the Importance of Selective mRNA Translation and Protein Turnover during Arabidopsis Seed Germination*

    Science.gov (United States)

    Galland, Marc; Huguet, Romain; Arc, Erwann; Cueff, Gwendal; Job, Dominique; Rajjou, Loïc

    2014-01-01

    During seed germination, the transition from a quiescent metabolic state in a dry mature seed to a proliferative metabolic state in a vigorous seedling is crucial for plant propagation as well as for optimizing crop yield. This work provides a detailed description of the dynamics of protein synthesis during the time course of germination, demonstrating that mRNA translation is both sequential and selective during this process. The complete inhibition of the germination process in the presence of the translation inhibitor cycloheximide established that mRNA translation is critical for Arabidopsis seed germination. However, the dynamics of protein turnover and the selectivity of protein synthesis (mRNA translation) during Arabidopsis seed germination have not been addressed yet. Based on our detailed knowledge of the Arabidopsis seed proteome, we have deepened our understanding of seed mRNA translation during germination by combining two-dimensional gel-based proteomics with dynamic radiolabeled proteomics using a radiolabeled amino acid precursor, namely [35S]-methionine, in order to highlight de novo protein synthesis, stability, and turnover. Our data confirm that during early imbibition, the Arabidopsis translatome keeps reflecting an embryonic maturation program until a certain developmental checkpoint. Furthermore, by dividing the seed germination time lapse into discrete time windows, we highlight precise and specific patterns of protein synthesis. These data refine and deepen our knowledge of the three classical phases of seed germination based on seed water uptake during imbibition and reveal that selective mRNA translation is a key feature of seed germination. Beyond the quantitative control of translational activity, both the selectivity of mRNA translation and protein turnover appear as specific regulatory systems, critical for timing the molecular events leading to successful germination and seedling establishment. PMID:24198433

  15. Bcl-2-associated athanogene 3 (BAG3) is an enhancer of small heat shock protein turnover via activation of autophagy in the heart.

    Science.gov (United States)

    Inomata, Yui; Nagasaka, Shouta; Miyate, Kazuki; Goto, Yuta; Hino, Chizuru; Toukairin, Chihiro; Higashio, Rieko; Ishida, Kinji; Saino, Tomoyuki; Hirose, Masamichi; Tsumura, Hideki; Sanbe, Atsushi

    2018-02-19

    Bcl-2-associated athanogene 3 (BAG3) is strongly expressed in both cardiac and skeletal muscle. A recent study showed that BAG3 may play a protective role in muscles. Little is known, however, regarding the detailed role of BAG3 in cardiac muscle. To better understand the functional role of cardiac BAG3 in the heart, we generated transgenic (TG) mice that overexpress BAG3. A decrease in fractional shortening, and the induction of cardiac atrial natriuretic peptide, were observed in BAG3 TG mice. Moreover, a marked reduction in the protein level of small HSPs was detected in BAG3 TG mouse hearts. We analyzed the cardiac small HSP levels when either the ubiquitin-proteasome system (UPS) or the autophagy system (AS) was inhibited in BAG3 TG mice. The protein turnovers of small HSPs by the AS were activated in BAG3 TG mouse hearts. Thus, BAG3 is critical for the protein turnover of small HSPs via activation of autophagy in the heart. Copyright © 2018 Elsevier Inc. All rights reserved.

  16. Influence of Sex and Estrogen on Musculotendinous Protein Turnover at Rest and After Exercise

    DEFF Research Database (Denmark)

    Hansen, Mette; Kjær, Michael

    2014-01-01

    Women differ from men with regard to muscle and tendon, most likely because of sex differences in estrogen. The present experimental findings suggest the hypothesis that estrogen has an anabolic effect on muscle primarily by lowering the protein turnover and enhancing sensitivity to resistance...... training. Furthermore, estrogen may reduce the stiffness of tendons, an effect that may be modified by physical training....

  17. Water turnover in reindeer. Some environmental implications

    International Nuclear Information System (INIS)

    Cameron, R.D.; Luick, J.R.; White, R.G.

    1982-01-01

    The nutritional and climatic effects on water turnover (determined using tritiated water) in reindeer are described. At low ambient temperatures (ca. -20 0 C) water turnover is related to protein and mineral intake, which is reflected in the relations of faecal and urinary water to nitrogen and ash excretion via these avenues. As ambient temperature increases, respiratory water, faecal water and urine flow increase, resulting in an increase in water turnover

  18. Effects of dietary protein and glycaemic index on biomarkers of bone turnover in children

    DEFF Research Database (Denmark)

    Dalskov, Stine-Mathilde; Müller, Martha; Ritz, Christian

    2014-01-01

    For decades, it has been debated whether high protein intake compromises bone mineralisation, but no long-term randomised trial has investigated this in children. In the family-based, randomised controlled trial DiOGenes (Diet, Obesity and Genes), we examined the effects of dietary protein...... and glycaemic index (GI) on biomarkers of bone turnover and height in children aged 5-18 years. In two study centres, families with overweight parents were randomly assigned to one of five ad libitum-energy, low-fat (25-30 % energy (E%)) diets for 6 months: low protein/low GI; low protein/high GI; high protein....../low GI; high protein/high GI; control. They received dietary instructions and were provided all foods for free. Children, who were eligible and willing to participate, were included in the study. In the present analyses, we included children with data on plasma osteocalcin or urinary N...

  19. Muscle protein turnover in rats treated with corticosterone (CC) or/and nandrolone decanoate (ND) and fed an adequate or a low-protein diet

    Energy Technology Data Exchange (ETDEWEB)

    Santidrian, S.; Cuevillas, F.; Goena, M.; Larralde, J.

    1986-03-01

    In order to investigate the possible antagonistic effect between glucocorticoids and androgens on muscle protein turnover, the authors have measured the fractional rates of gastrocnemius muscle protein synthesis (k/sub s/) and degradation (k/sub d/) by the constant-intravenous-infusion method using L-//sup 14/C/-tyrosine in rats receiving via s.c. per 100 g b.wt. 10 mg of CC, or 2 mg of ND or CC+ND at the indicated doses, and fed either an 18% or 5% protein diets over a period of 5 days. As an additional index of protein synthesis, RNA activity (g of synthesized protein/day/g RNA) was determined as well. Results showed that as compared to vehicle-injected animals fed the adequate diet, CC-treated rats exhibited a reduction of muscle k/sub d/, while ND-treated rats had an outstanding increase of muscle k/sub s/. However, rats receiving CC+ND showed k/sub s/ and k/sub d/ values similar to those displayed by control animals. Nevertheless, when the steroids were injected to rats fed the low-protein diet, CC has a catabolic effect on muscle protein but by reducing k/sub s/, while the anabolic action of ND is still displayed but by a significant reduction of muscle k/sub d/. CC+ND given to these protein-deficient rats caused an increase in muscle k/sub s/ and a reduction in k/sub d/. These results might indicate that, at least in part, ND antagonizes the catabolic action of high doses of CC on muscle protein metabolism.

  20. Muscle protein turnover in rats treated with corticosterone (CC) or/and nandrolone decanoate (ND) and fed an adequate or a low-protein diet

    International Nuclear Information System (INIS)

    Santidrian, S.; Cuevillas, F.; Goena, M.; Larralde, J.

    1986-01-01

    In order to investigate the possible antagonistic effect between glucocorticoids and androgens on muscle protein turnover, the authors have measured the fractional rates of gastrocnemius muscle protein synthesis (k/sub s/) and degradation (k/sub d/) by the constant-intravenous-infusion method using L-/ 14 C/-tyrosine in rats receiving via s.c. per 100 g b.wt. 10 mg of CC, or 2 mg of ND or CC+ND at the indicated doses, and fed either an 18% or 5% protein diets over a period of 5 days. As an additional index of protein synthesis, RNA activity (g of synthesized protein/day/g RNA) was determined as well. Results showed that as compared to vehicle-injected animals fed the adequate diet, CC-treated rats exhibited a reduction of muscle k/sub d/, while ND-treated rats had an outstanding increase of muscle k/sub s/. However, rats receiving CC+ND showed k/sub s/ and k/sub d/ values similar to those displayed by control animals. Nevertheless, when the steroids were injected to rats fed the low-protein diet, CC has a catabolic effect on muscle protein but by reducing k/sub s/, while the anabolic action of ND is still displayed but by a significant reduction of muscle k/sub d/. CC+ND given to these protein-deficient rats caused an increase in muscle k/sub s/ and a reduction in k/sub d/. These results might indicate that, at least in part, ND antagonizes the catabolic action of high doses of CC on muscle protein metabolism

  1. Whole-body protein turnover in malnourished patients with child class B and C cirrhosis on diets low to high in protein energy.

    Science.gov (United States)

    Dichi, J B; Dichi, I; Maio, R; Correa, C R; Angeleli, A Y; Bicudo, M H; Rezende, T A; Burini, R C

    2001-03-01

    The purpose of this study was to determine the rate of whole-body protein turnover in moderately and severely alcoholic, malnourished, cirrhotic patients fed with different amounts of protein or energy. Six male patients (Child classes B and C) and four age- and sex-matched healthy control subjects were studied for 18 d in fasting and feeding states; a single oral dose of [(15)N]glycine was used as a tracer and urinary ammonia was the end product. The kinetic study showed that patients had higher protein catabolism while fasting (patients: 3.14 +/- 1.2 g of lean body mass/9 h; controls: 1.8 +/- 0.3 g of lean body mass/9 h; P hyperproteic/hyperenergetic diet when compared with fasting. Nitrogen retention was consistent with the lower protein-catabolism rate; a statistically significant increase in nitrogen balance was observed when patients were fed with the hyperproteic/hyperenergetic diet compared with fasting (4.3 +/- 3.2 g of nitrogen/d and -2.2 +/- 1.9 g of nitrogen/d, respectively; P hyperproteic/hyperenergetic diet is likely needed to improve their clinical and nutritional status.

  2. New aspects of protein stability and turnover in the regulation of genome integrity

    DEFF Research Database (Denmark)

    Gallina, Irene

    of DNA repair is the control of protein abundance, both at a global cellular level, and locally at the site of damage. This is achieved through transcriptional regulation of protein synthesis and through the control of protein stability and turnover. In this study, we investigate the role of Rad56...... sensitivity when mutant. Prior to the work presented here,all these loci have been mapped to a specific gene except RAD56. We map the rad56-1 mutation to the NAT3 gene, which encodes the catalytic subunit of the NatB N-terminal acetyltransferase in yeast. Deletion of RAD56 causes sensitivity to X-rays, methyl......-scale studies investigating factors involved in DNA metabolism, but no specific function has been assigned to Cmr1. Taking advantage of a series of high-throughput screens we characterize Cmr1 as a chromatinassociated protein, involved in the regulation of fork progression in the presence of replication stress...

  3. Coupling of kinesin ATP turnover to translocation and microtubule regulation: one engine, many machines.

    Science.gov (United States)

    Friel, Claire T; Howard, Jonathon

    2012-12-01

    The cycle of ATP turnover is integral to the action of motor proteins. Here we discuss how variation in this cycle leads to variation of function observed amongst members of the kinesin superfamily of microtubule associated motor proteins. Variation in the ATP turnover cycle among superfamily members can tune the characteristic kinesin motor to one of the range of microtubule-based functions performed by kinesins. The speed at which ATP is hydrolysed affects the speed of translocation. The ratio of rate constants of ATP turnover in relation to association and dissociation from the microtubule influence the processivity of translocation. Variation in the rate-limiting step of the cycle can reverse the way in which the motor domain interacts with the microtubule producing non-motile kinesins. Because the ATP turnover cycle is not fully understood for the majority of kinesins, much work remains to show how the kinesin engine functions in such a wide variety of molecular machines.

  4. The staphylococcal accessory regulator, SarA, is an RNA-binding protein that modulates the mRNA turnover properties of late-exponential and stationary phase Staphylococcus aureus cells

    Directory of Open Access Journals (Sweden)

    John M Morrison

    2012-03-01

    Full Text Available The modulation of mRNA turnover is gaining recognition as a mechanism by which Staphylococcus aureus regulates gene expression, but the factors that orchestrate alterations in transcript degradation are poorly understood. In that regard, we previously found that 138 mRNA species, including the virulence factors protein A (spa and collagen binding protein (cna, are stabilized in a sarA-dependent manner during exponential phase growth, suggesting that SarA protein may directly or indirectly effect the RNA turnover properties of these transcripts. Herein, we expanded our characterization of the effects of sarA on mRNA turnover during late exponential and stationary phases of growth. Results revealed that the locus affects the RNA degradation properties of cells during both growth phases. Further, using gel mobility shift assays and RIP-ChIP, it was found that SarA protein is capable of binding mRNA species that it stabilizes both in vitro and within bacterial cells. Taken together, these results suggest that SarA post-transcriptionally regulates S. aureus gene expression in a manner that involves binding to and consequently altering the mRNA turnover properties of target transcripts.

  5. Employee Turnover among Full-time Public Librarians.

    Science.gov (United States)

    Rubin, Richard

    1989-01-01

    A study of employee turnover in 31 public libraries in the American Midwest established baseline turnover rates and examined the relationship of gender to turnover behavior. Findings showed that: turnover rates are low compared to other occupations; and turnover rates of males and females are similar. (28 references) (Author/MES)

  6. Proteome-wide analysis of protein abundance and turnover remodelling during oncogenic transformation of human breast epithelial cells [version 1; referees: 2 approved, 1 approved with reservations

    Directory of Open Access Journals (Sweden)

    Tony Ly

    2018-05-01

    Full Text Available Background: Viral oncogenes and mutated proto-oncogenes are potent drivers of cancer malignancy. Downstream of the oncogenic trigger are alterations in protein properties that give rise to cellular transformation and the acquisition of malignant cellular phenotypes. Developments in mass spectrometry enable large-scale, multidimensional characterisation of proteomes. Such techniques could provide an unprecedented, unbiased view of how oncogene activation remodels a human cell proteome. Methods: Using quantitative MS-based proteomics and cellular assays, we analysed how transformation induced by activating v-Src kinase remodels the proteome and cellular phenotypes of breast epithelial (MCF10A cells. SILAC MS was used to comprehensively characterise the MCF10A proteome and to measure v-Src-induced changes in protein abundance across seven time-points (1-72 hrs. We used pulse-SILAC MS (Boisvert et al., 2012, to compare protein synthesis and turnover in control and transformed cells. Follow-on experiments employed a combination of cellular and functional assays to characterise the roles of selected Src-responsive proteins. Results: Src-induced transformation changed the expression and/or turnover levels of ~3% of proteins, affecting ~1.5% of the total protein molecules in the cell. Transformation increased the average rate of proteome turnover and disrupted protein homeostasis. We identify distinct classes of protein kinetics in response to Src activation. We demonstrate that members of the polycomb repressive complex 1 (PRC1 are important regulators of invasion and migration in MCF10A cells. Many Src-regulated proteins are present in low abundance and some are regulated post-transcriptionally. The signature of Src-responsive proteins is highly predictive of poor patient survival across multiple cancer types. Open access to search and interactively explore all these proteomic data is provided via the EPD database (www.peptracker.com/epd. Conclusions

  7. Evidence for the Deregulation of Protein Turnover Pathways in Atm-Deficient Mouse Cerebellum: An Organotypic Study.

    Science.gov (United States)

    Kim, Catherine D; Reed, Ryan E; Juncker, Meredith A; Fang, Zhide; Desai, Shyamal D

    2017-07-01

    Interferon-stimulated gene 15 (ISG15), an antagonist of the ubiquitin pathway, is elevated in cells and brain tissues obtained from ataxia telangiectasia (A-T) patients. Previous studies reveal that an elevated ISG15 pathway inhibits ubiquitin-dependent protein degradation, leading to activation of basal autophagy as a compensatory mechanism for protein turnover in A-T cells. Also, genotoxic stress (ultraviolet [UV] radiation) deregulates autophagy and induces aberrant degradation of ubiquitylated proteins in A-T cells. In the current study, we show that, as in A-T cells, ISG15 protein expression is elevated in cerebellums and various other tissues obtained from Atm-compromised mice in an Atm-allele-dependent manner (Atm+/+ Atm+/- Atm-/-). Notably, in cerebellums, the brain part primarily affected in A-T, levels of ISG15 were significantly greater (3-fold higher) than cerebrums obtained from the same set of mice. Moreover, as in A-T cell culture, UV induces aberrant degradation of ubiquitylated proteins and autophagy in Atm-deficient, but not in Atm-proficient, cerebellar brain slices grown in culture. Thus, the ex vivo organotypic A-T mouse brain culture model mimics that of an A-T human cell culture model and could be useful for studying the role of ISG15-dependent proteinopathy in cerebellar neurodegeneration, a hallmark of A-T in humans. © 2017 American Association of Neuropathologists, Inc. All rights reserved.

  8. Sucrose-phosphate synthase in tree species: light/dark regulation involves a component of protein turnover in Prosopis juliflora (SW DC).

    Science.gov (United States)

    Sinha, A K; Shirke, P A; Pathre, U; Sane, P V

    1997-10-01

    Light dependent modulation of sucrose-phosphate synthase activity (SPS; EC 2.4.1.14) was studied in a tree species, namely Prosopis juliflora. In this paper we demonstrate that cycloheximide, an inhibitor of cytoplasmic protein synthesis, when fed to detached leaves of P. juliflora through transpiration stream in the dark or in light completely prevents in vivo light activation of Vlim and Vmax activities of SPS. In case of spinach, however, cycloheximide feeding affects only Vlim activity while Vmax activity remained unchanged. In contrast, chloramphenicol, an inhibitor of protein synthesis in chloroplast has no effect on the light activation of SPS in Prosopis. The treatment with cycloheximide showed slight reduction in the rate of O2 evolution indicating that cycloheximide had very little effect on overall photosynthesis. These results indicate that short term protein turnover of the SPS protein and some other essential component(s) (e.g., a putative protein that modifies SPS activity) is one of the primary steps in a complex and unique regulatory cascade effecting the reversible light activation of SPS.

  9. Innovative scattering analysis shows that hydrophobic disordered proteins are expanded in water

    Energy Technology Data Exchange (ETDEWEB)

    Riback, Joshua A.; Bowman, Micayla A.; Zmyslowski, Adam M.; Knoverek, Catherine R.; Jumper, John M.; Hinshaw, James R.; Kaye, Emily B.; Freed, Karl F.; Clark, Patricia L.; Sosnick, Tobin R.

    2017-10-12

    A substantial fraction of the proteome is intrinsically disordered, and even well-folded proteins adopt non-native geometries during synthesis, folding, transport, and turnover. Characterization of intrinsically disordered proteins (IDPs) is challenging, in part because of a lack of accurate physical models and the difficulty of interpreting experimental results. We have developed a general method to extract the dimensions and solvent quality (self-interactions) of IDPs from a single small-angle x-ray scattering measurement. We applied this procedure to a variety of IDPs and found that even IDPs with low net charge and high hydrophobicity remain highly expanded in water, contrary to the general expectation that protein-like sequences collapse in water. Our results suggest that the unfolded state of most foldable sequences is expanded; we conjecture that this property was selected by evolution to minimize misfolding and aggregation.

  10. Associations of total, dairy, and meat protein with markers for bone turnover in healthy, prepubertal boys

    DEFF Research Database (Denmark)

    Budek, Alicja Zofia; Hoppe, Camilla; Michaelsen, Kim Fleischer

    2007-01-01

    intake was estimated from a 3-d weighed food record. sIGF-I and its binding protein-3 were assessed (immunoassay) in a subgroup of 56 boys. All statistical models included effects of age, BMI, and energy intake. Dairy protein was negatively associated with sOC (P ¼ 0.05) but not significantly associated......We previously reported that high intake of milk, but not meat, equal in protein content, increased serum insulin-like growth factor-I (sIGF-I) in prepubertal boys. sIGF-I plays a key role in bone metabolism. Therefore, the aim of this cross-sectional study was to investigate associations of total.......04) but not significantly associated with sOC and sCTX. Free sIGF-I was positively associated with total (P , 0.01) and dairy (P ¼ 0.06) protein but not with meat protein. Our results indicate that dairy and meat protein may exhibit a distinct regulatory effect on different markers for bone turnover. Future studies should...

  11. Effects of experimental hyperthyroidism on protein turnover in skeletal and cardiac muscle as measured by [14C]tyrosine infusion.

    OpenAIRE

    Carter, W J; Benjamin, W S; Faas, F H

    1982-01-01

    The effect of T3 (3,3',5-tri-iodothyronine) on protein turnover in skeletal and cardiac muscle was measured in intact rats by means of a 6 h [14C]tyrosine-infusion technique. Treatment with 25-30 micrograms of T3/100 g body wt. daily for 4-7 days increased the fractional rate of protein synthesis in skeletal muscle. Since the fractional growth rate of the muscle was decreased or unchanged, T3 treatment increased the rate of muscle protein breakdown. These findings suggest that increased prote...

  12. Studies on water turnover and water requirement in buffalo calves fed on different levels of energy and protein in the diet

    International Nuclear Information System (INIS)

    Verma, D.N.; Kumar, N.; Dass, R.S.; Singh, U.B.

    1980-01-01

    Experiments were conducted for measuring water turnover and water requirement in buffalo calves fed on different levels of energy and protein in the diet. There was significant difference (P<0.01) in the biological half life of tritiated water between various groups of animals. Water turnover rates were statistically (P<0.05) more in groups I and II (106.52 and 99.74 ml/kg/24 hr) than groups III and IV (93.03 and 77.09 ml/kg/24 hr). There was no significant difference in water requirement due to various treatments. (author)

  13. Muscle protein turnover in cattle of differing genetic backgrounds as measured by urinary N tau-methylhistidine excretion

    International Nuclear Information System (INIS)

    McCarthy, F.D.; Bergen, W.G.; Hawkins, D.R.

    1983-01-01

    N tau-methylhistidine (N tau MH) was used as an index for muscle protein degradation and this index was utilized to evaluate degradation rates in young growing cattle. Initially, two Charolais crossbred heifers, 12 months of age, were used to measure the recovery of radioactivity in the urine for a 120-hour period after intravenous injection of [ 14 C]N tau MH. Of the radioactivity injected into the animals, 89.7% was recovered after 120 hours. With rate and amount of clearance as the criteria, the excretion of N tau MH in urine appears to be a valid index of muscle protein degradation in cattle. Eight steers of two genetic types were used to evaluate the effect of frame size on turnover rates of muscle proteins with N tau MH as an index. Large frame cattle (LG) excreted more N tau MH per day throughout the trial. Total daily creatinine excretion was less for small frame (SM) cattle showing an increase with time in LG and SM cattle. N tau MH-to-creatinine ratios showed a decline with time. Fractional breakdown rates (FBR) and fractional synthesis rates (FSR) appeared to parallel each other with rates tending to decrease with age. No differences were observed between LG and SM cattle for FBR, FSR or fractional growth rate

  14. The glomuvenous malformation protein Glomulin binds Rbx1 and regulates cullin RING ligase-mediated turnover of Fbw7.

    Science.gov (United States)

    Tron, Adriana E; Arai, Takehiro; Duda, David M; Kuwabara, Hiroshi; Olszewski, Jennifer L; Fujiwara, Yuko; Bahamon, Brittany N; Signoretti, Sabina; Schulman, Brenda A; DeCaprio, James A

    2012-04-13

    Fbw7, a substrate receptor for Cul1-RING-ligase (CRL1), facilitates the ubiquitination and degradation of several proteins, including Cyclin E and c-Myc. In spite of much effort, the mechanisms underlying Fbw7 regulation are mostly unknown. Here, we show that Glomulin (Glmn), a protein found mutated in the vascular disorder glomuvenous malformation (GVM), binds directly to the RING domain of Rbx1 and inhibits its E3 ubiquitin ligase activity. Loss of Glmn in a variety of cells, tissues, and GVM lesions results in decreased levels of Fbw7 and increased levels of Cyclin E and c-Myc. The increased turnover of Fbw7 is dependent on CRL and proteasome activity, indicating that Glmn modulates the E3 activity of CRL1(Fbw7). These data reveal an unexpected functional connection between Glmn and Rbx1 and demonstrate that defective regulation of Fbw7 levels contributes to GVM. Copyright © 2012 Elsevier Inc. All rights reserved.

  15. Regulation of endoplasmic reticulum turnover by selective autophagy

    NARCIS (Netherlands)

    Khaminets, Aliaksandr; Heinrich, Theresa; Mari, Muriel; Grumati, Paolo; Huebner, Antje K; Akutsu, Masato; Liebmann, Lutz; Stolz, Alexandra; Nietzsche, Sandor; Koch, Nicole; Mauthe, Mario; Katona, Istvan; Qualmann, Britta; Weis, Joachim; Reggiori, Fulvio; Kurth, Ingo; Hübner, Christian A; Dikic, Ivan

    2015-01-01

    The endoplasmic reticulum (ER) is the largest intracellular endomembrane system, enabling protein and lipid synthesis, ion homeostasis, quality control of newly synthesized proteins and organelle communication. Constant ER turnover and modulation is needed to meet different cellular requirements and

  16. Regulation of endoplasmic reticulum turnover by selective autophagy

    NARCIS (Netherlands)

    Khaminets, Aliaksandr; Heinrich, Theresa; Mari, Muriel; Grumati, Paolo; Huebner, Antje K.; Akutsu, Masato; Liebmann, Lutz; Stolz, Alexandra; Nietzsche, Sandor; Koch, Nicole; Mauthe, Mario; Katona, Istvan; Qualmann, Britta; Weis, Joachim; Reggiori, Fulvio; Kurth, Ingo; Huebner, Christian A.; Dikic, Ivan

    2015-01-01

    The endoplasmic reticulum (ER) is the largest intracellular endomembrane system, enabling protein and lipid synthesis, ion homeostasis, quality control of newly synthesized proteins and organelle communication(1). Constant ER turnover and modulation is needed to meet different cellular requirements

  17. Protein turnover in malnourished patients with cystic fibrosis: Effects of elemental and nonelemental nutritional supplements

    International Nuclear Information System (INIS)

    Pelekanos, J.T.; Holt, T.L.; Ward, L.C.; Cleghorn, G.J.; Shepherd, R.W.

    1990-01-01

    To evaluate the relative efficacy of nonelemental versus semielemental enteral supplements for nutritional rehabilitation of cystic fibrosis (CF) patients, whole-body protein turnover using the [ 15 N]glycine method was studied in nine malnourished CF patients during enteral feedings, in a block design study comparing a semielemental formula (Criticare), a higher protein density but nonelemental formula (Traumacal) (T), and a nonelemental formula that had been modified to become isocaloric and isonitrogenous to the semielemental formula (modified Traumacal, MT). No significant differences in rates of protein synthesis or catabolism were observed comparing the three formulas. However, the higher protein density nonelemental formula resulted in higher net protein deposition compared to the other two formulas (T + 0.42 g kg-1 10 h-1 versus 0.33 g kg-1 10 h-1 for Criticare and -0.59 g kg-1 10 h-1 for MT), although this was significant (p less than 0.05) for the MT versus T comparison only. This study lends support to the use of less expensive nonelemental formulas for the nutritional management of malnourished patients with CF

  18. Dual pathways for ribonucleic acid turnover in WI-38 but not in I-cell human diploid fibroblasts

    International Nuclear Information System (INIS)

    Sameshima, M.; Liebhaber, S.A.; Schlessinger, D.

    1981-01-01

    The turnover rates of /sup 3/H-labeled 18S ribosomal ribonucleic acid (RNA), 28S ribsomal RNA, transfer RNA, and total cytoplasmic RNA were very similar in growing WI-38 diploid fibroblasts. The rate of turnover was at least twofold greater when cell growth stopped due to cell confluence, /sup 3/H irradiation, or treatment with 20 mM NaN/sub 3/ or 2 mM NaF. In contrast, the rate of total /sup 3/H-protein turnover was the same in growing and nongrowing cells. Both RNA and protein turnovers were accelerated at least twofold in WI-38 cells deprived of serum, and this increase in turnover was inhibited by NH/sub 4/Cl. These results are consistent with two pathways for RNA turnover, oe of them being nonlysosomal and the other being lyosome mediated (NH/sub 4/Cl sensitive), as has been suggested for protein turnover. Also consistent with the notion of two pathways for RNA turnover were findings with I-cells, which are deficient for many lysosomal enzymes, and in which all RNA turnover were nonlysosomal (NH/sub 4/Cl resistant)

  19. Effect of compounds astragalus extract and cysteamine on finishing pigs growth and protein turnover

    International Nuclear Information System (INIS)

    Wang Cheng; Wang Zhisheng; Zhou Anguo; Liu Guilian; Xue Bai

    2008-01-01

    32 PIC pigs, weighted 59.82±1.32 kg on average, were subjected randomly to 4 treatments for determining the effects of extrogenous metabolism-regulating agents on pig performance, protein turn-over and nitrogen retention by using isotope ( 15 N-Gly) technique and nitrogen balance trial. The 4 treatments were: (1) basal diet; (2) basal diet plus cysteamine (70mg/kg, CS group); (3) basal diet plus non-stable astragalus extracts 250mg/kg (NCAE group); (4) basal diet plus stably astragalus extracts 250mg/kg (CAE group). Astragalus extracts and cysteamine, especially NCAE, redounded to increase pig performance, especially increase average day gain (P<0.05). Both astragalus extracts and cysteamine accelerated protein aggradation rate and amino acid utilization rate, as well as biological value. Astragalus extracts helped to accelerate the synthesis rate of amino acid into body protein and reduce the excretion rate of endogenous urine nitrogen. The mechanism of increasing protein deposition of cysteamine is reducing body protein degradation rate (26.71% reduction, compared to control group), while that of astragalus extracts is bilateral, reducing protein degradation rate (24.84% and 3.66% reduction for NCAE and CAE) and accelerating protein synthesis rate (22.86% and 19.18% increase for NCAE and CAE). Both astragalus extracts and cysteamine contributed the increasing nitrogen retention, net nitrogen utilization and biological value. (authors)

  20. Regulation of myofibrillar accumulation in chick muscle cultures - Evidence for the involvement of calcium and lysosomes in non-uniform turnover of contractile proteins

    Science.gov (United States)

    Silver, Geri; Etlinger, Joseph D.

    1985-01-01

    The effects of calcium on the synthesis and the degradation of individual myofibrillar proteins were investigated using primary chick-leg skeletal muscle cultures labeled with S-35-methionine (for protein accumulation experiments) or Ca(2+)-45 (for calcium efflux experiments). It was found that the turnover of individual contractile proteins is regulated nonuniformly by a calcium-dependent mechanism involving lysosomes. The results also indicate that contractile proteins are released from the myofibril before their breakdown to amino acids.

  1. Blood protein turnover in parasitized ruminants. The influence of host nutrition

    International Nuclear Information System (INIS)

    Dargie, J.D.

    1981-01-01

    Ruminants infected with helminth or protozoal parasites generally become anaemic and hypoalbuminaemic, as well as losing their appetite. Since feed intake plays an important part in determining blood protein levels, it is necessary, when attempting to determine the mechanisms by which parasites cause anaemia and hypoalbuminaemia, to differentiate between the effects of feed intake per se and the specific effects of the parasite on blood protein turnover. This can be done by a variety of radioisotope techniques using infected and pair-fed control animals. Additionally, animals on a poor plane of nutrition suffer more from parasitism than those which are well fed. To understand the reason for this, it is necessary to determine whether diet influences susceptibility to parasite establishment or survival, and/or susceptibility to the metabolic consequences of parasitism. Described here is the current state of knowledge on the interaction between host nutrition and susceptibility to parasitic infection and parasitic disease processes, with particular reference to anaemia and hypoalbuminaemia. It is concluded that there is little evidence that nutrition has a significant bearing on resistance or susceptibility to infection, but that it does not have a profound influence on the ability of animals to withstand the pathogenic effects of parasites. The reasons for this are discussed in detail, but the principal benefit of a good plane of nutrition is that it enables the synthetic machinery of the host to keep pace with the concurrent parasite-induced hypercatabolism of blood proteins. (author)

  2. Serum biomarker profile associated with high bone turnover and BMD in postmenopausal women.

    Science.gov (United States)

    Bhattacharyya, Sudeepa; Siegel, Eric R; Achenbach, Sara J; Khosla, Sundeep; Suva, Larry J

    2008-07-01

    Early diagnosis of the onset of osteoporosis is key to the delivery of effective therapy. Biochemical markers of bone turnover provide a means of evaluating skeletal dynamics that complements static measurements of BMD by DXA. Conventional clinical measurements of bone turnover, primarily the estimation of collagen and its breakdown products in the blood or urine, lack both sensitivity and specificity as a reliable diagnostic tool. As a result, improved tests are needed to augment the use of BMD measurements as the principle diagnostic modality. In this study, the serum proteome of 58 postmenopausal women with high or low/normal bone turnover (training set) was analyzed by surface enhanced laser-desorption/ionization time-of-flight mass spectrometry, and a diagnostic fingerprint was identified using a variety of statistical and machine learning tools. The diagnostic fingerprint was validated in a separate distinct test set, consisting of serum samples from an additional 59 postmenopausal women obtained from the same Mayo cohort, with a gap of 2 yr. Specific protein peaks that discriminate between postmenopausal patients with high or low/normal bone turnover were identified and validated. Multiple supervised learning approaches were able to classify the level of bone turnover in the training set with 80% sensitivity and 100% specificity. In addition, the individual protein peaks were also significantly correlated with BMD measurements in these patients. Four of the major discriminatory peaks in the diagnostic profile were identified as fragments of interalpha-trypsin-inhibitor heavy chain H4 precursor (ITIH4), a plasma kallikrein-sensitive glycoprotein that is a component of the host response system. These data suggest that these serum protein fragments are the serum-borne reflection of the increased osteoclast activity, leading to the increased bone turnover that is associated with decreasing BMD and presumably an increased risk of fracture. In conjunction with the

  3. Effects of resistance training and protein supplementation on bone turnover in young adult women

    Directory of Open Access Journals (Sweden)

    Sinning Wayne E

    2005-08-01

    Full Text Available Abstract Background The strength of aging bone depends on the balance between the resorption and formation phases of the remodeling process. The purpose of this study was to examine the interaction of two factors with the potential to exert opposing influences on bone turnover, resistance exercise training and high dietary protein intake. It was hypothesized that resistance training by young, healthy, untrained women with protein intakes near recommended levels (0.8 g·kg-1·d-1 would promote bone formation and/or inhibit bone resorption, and that subsequent supplementation to provide 2.4 g protein·kg-1·d-1 would reverse these effects. Methods Bone formation was assessed with serum bone-specific alkaline phosphatase (BAP and osteocalcin (OC, and bone resorption with urinary calcium and deoxypyridinoline (DPD. Biochemical, strength, anthropometric, dietary, and physical activity data were obtained from 24 healthy, untrained, eumenorrheic women (18–29y at baseline, after eight weeks of resistance training (3 d·wk-1, ~1 hr·d-1; 3 sets, 6–10 repetitions, 13 exercises, 75–85% maximum voluntary contraction, and after 12 weeks of resistance training and 10 days of protein/placebo supplementation. Subjects were randomized (double-blind to either a high protein (HP or training control (TC group and, during the final 10 days, consumed either enough purified whey protein to bring daily protein intake to 2.4 g·kg-1·d-1, or an equivalent dose of isoenergetic, carbohydrate placebo. Results Strength, lean tissue mass, and DPD increased significantly in both groups over time, while percent body fat and BAP decreased (repeated measures ANOVA, p ≤ 0.05, Bonferroni correction. No significant changes were observed for serum OC or urinary calcium, and no significant group (TC, HP × time (baseline, week 8, week 12 interactions emerged for any of the biochemical measures. Conclusion (1 Twelve weeks of high-intensity resistance training did not appear to

  4. Efficacy of Corrected Rapid Turnover Protein Increment Index (CRII) for Early Detection of Improvement of Nutrition Status in Patients with Malnutrition

    OpenAIRE

    Suyama, Yohji; Adachi, Kyoichi; Notsu, Yoshitomo; Satoh, Emi; Nariai, Yukiko; Hashimoto, Yohko; Sumi, Asako; Kawaguchi, Mikiko; Ishimura, Norihisa

    2009-01-01

    Serum prealbumin level is useful for assessment of changes in nutritional status but it is markedly affected by the inflammation. In this study, we examined the efficacy of the corrected rapid turnover protein increment index (CRII) for prealbumin, which is calculated as [prealbumin level/C-reactive protein (CRP) level on the assessment day]/[prealbumin level/CRP level on the day of starting nutritional care], for prediction of improvement of nutritional status in patients with malnutrition. ...

  5. Development of a method for the accurate measurement of protein turnover in neoplastic cells grown in culture

    International Nuclear Information System (INIS)

    Silverman, J.A.

    1984-01-01

    In this study, it was shown that standard techniques for cell recovery and sample preparation for liquid scintillation counting led to underestimation of the radioactivity present in cell proteins by 20-40%. These techniques involved labeling with 3 He leucine or 14 C leucine, scraping the cells from the dish in a buffer, TCA precipitation of the cell proteins, solubilization in NaOH and counting in a liquid scintillation counter. Hydrolysis of the proteins with HCl or Pronase significantly increased the recovery of the labeled proteins. Also, solubilization in situ with NaOH or hydrolysis in situ with Pronase recovered 5-10% additional labeled proteins. The techniques developed here allow the accurate measurement of radioactivity in cell proteins. In addition, these techniques were used to study protein turnover in rat hepatoma cells grown in culture. These cells regulated their growth rate through changes in the protein synthesis rate as opposed to changes in the protein degradation rate. These data support the hypothesis that neoplastic cells, unlike normal cells, do not regulate proteolysis in growth control; normal cells under similar conditions have been shown to activate lysosomal proteolysis as they reach confluence. The physiologic implications of this observation are discussed

  6. Turnover and metabolism of phosphatidylglycerol acyl moieties in E. coli

    International Nuclear Information System (INIS)

    Cooper, C.L.; Rock, C.O.

    1987-01-01

    Fatty acids synthesized in mutants (plsB) blocked in de novo phospholipid biosynthesis were preferentially transferred to phosphatidylglycerol (PtdGro). The ratio of phospholipid species labeled with 32 P and [ 3 H]acetate in the absence of glycerol-3-P acyltransferase activity indicated that [ 3 H]acetate incorporation into PtdGro was due to fatty acid turnover. The magnitude of the turnover process was difficult to estimate due to a significant contraction of the acetyl-CoA pool following the inhibition of phospholipid synthesis. A possible connection between PtdGro turnover and protein acylation was investigated in an E. coli strain containing a lipoprotein expression vector. Cells were prelabeled with [ 3 H]acetate and lipoprotein expression was induced concomitant with the addition of exogenous [ 14 C]-palmitate. [ 14 C] Palmitate was assimilated into the l-position of phosphatidylethanolamine and transferred to the amino terminus of the lipoprotein. In contrast, the ester-linked lipoprotein fatty acids and PtdGro were not enriched in carbon-14 implying a metabolic relationship between these two pools. The data suggest that turnover of PtdGro acyl moieties is related to protein acylation, but a direct link between the two processes remains to be established

  7. Naturally occurring stable isotopes reflect changes in protein turnover and growth in gilthead sea bream (Sparus aurata) juveniles under different dietary protein levels.

    Science.gov (United States)

    Martin-Perez, Miguel; Fernandez-Borras, Jaume; Ibarz, Antoni; Felip, Olga; Fontanillas, Ramon; Gutierrez, Joaquim; Blasco, Josefina

    2013-09-18

    Ideal nutritional conditions are crucial to sustainable aquaculture due to economic and environmental issues. Here we apply stable isotope analysis as an indicator of fish growth and feeding balance, to define the optimum diet for efficient growing conditions. Juveniles of gilthead sea bream were fed with six isoenergetic diets differing in protein to lipid proportion (from 41/26 to 57/20). As protein intake increased, δ¹⁵N and Δδ¹⁵N of muscle and Δδ¹⁵N and Δδ¹³C of its protein fraction decreased, indicating lower protein turnover and higher protein deposition in muscle. This is reflected in the inverse relationship found between Δδ¹⁵N and growth rate, although no differences were observed in either parameter beyond the protein/lipid proportion 47/23. Principal component analysis (PCA) also signaled 47/23 diet as the pivotal point with the highest growing efficiency, with isotopic parameters having the highest discrimination load. Thus, muscle isotope composition, especially ¹⁵N, can be used to evaluate nutritional status in farmed fish.

  8. Measuring protein breakdown rate in individual proteins in vivo

    DEFF Research Database (Denmark)

    Holm, Lars; Kjaer, Michael

    2010-01-01

    To outline different approaches of how protein breakdown can be quantified and to present a new approach to determine the fractional breakdown rate of individual slow turnover proteins in vivo.......To outline different approaches of how protein breakdown can be quantified and to present a new approach to determine the fractional breakdown rate of individual slow turnover proteins in vivo....

  9. The costs of turnover in nursing homes.

    Science.gov (United States)

    Mukamel, Dana B; Spector, William D; Limcangco, Rhona; Wang, Ying; Feng, Zhanlian; Mor, Vincent

    2009-10-01

    Turnover rates in nursing homes have been persistently high for decades, ranging upwards of 100%. To estimate the net costs associated with turnover of direct care staff in nursing homes. DATA AND SAMPLE: Nine hundred two nursing homes in California in 2005. Data included Medicaid cost reports, the Minimum Data Set, Medicare enrollment files, Census, and Area Resource File. We estimated total cost functions, which included in addition to exogenous outputs and wages, the facility turnover rate. Instrumental variable limited information maximum likelihood techniques were used for estimation to deal with the endogeneity of turnover and costs. The cost functions exhibited the expected behavior, with initially increasing and then decreasing returns to scale. The ordinary least square estimate did not show a significant association between costs and turnover. The instrumental variable estimate of turnover costs was negative and significant (P = 0.039). The marginal cost savings associated with a 10% point increase in turnover for an average facility was $167,063 or 2.9% of annual total costs. The net savings associated with turnover offer an explanation for the persistence of this phenomenon over the last decades, despite the many policy initiatives to reduce it. Future policy efforts need to recognize the complex relationship between turnover and costs.

  10. The longitudinal study of turnover and the cost of turnover in EMS

    Science.gov (United States)

    Patterson, P. Daniel; Jones, Cheryl B.; Hubble, Michael W.; Carr, Matthew; Weaver, Matthew D.; Engberg, John; Castle, Nicholas

    2010-01-01

    Purpose Few studies have examined employee turnover and associated costs in emergency medical services (EMS). The purpose of this study was to quantify the mean annual rate of turnover, total median cost of turnover, and median cost per termination in a diverse sample of EMS agencies. Methods A convenience sample of 40 EMS agencies was followed over a 6 month period. Internet, telephone, and on-site data collection methods were used to document terminations, new hires, open positions, and costs associated with turnover. The cost associated with turnover was calculated based on a modified version of the Nursing Turnover Cost Calculation Methodology (NTCCM). The NTCCM identified direct and indirect costs through a series of questions that agency administrators answered monthly during the study period. A previously tested measure of turnover to calculate the mean annual rate of turnover was used. All calculations were weighted by the size of the EMS agency roster. The mean annual rate of turnover, total median cost of turnover, and median cost per termination were determined for 3 categories of agency staff mix: all paid staff, mix of paid and volunteer (mixed), and all-volunteer. Results The overall weighted mean annual rate of turnover was 10.7%. This rate varied slightly across agency staffing mix: (all-paid=10.2%, mixed=12.3%, all-volunteer=12.4%). Among agencies that experienced turnover (n=25), the weighted median cost of turnover was $71,613.75, which varied across agency staffing mix: (all-paid=$86,452.05, mixed=$9,766.65, and all-volunteer=$0). The weighted median cost per termination was $6,871.51 and varied across agency staffing mix: (all-paid=$7,161.38, mixed=$1,409.64, and all-volunteer=$0). Conclusions Annual rates of turnover and costs associated with turnover vary widely across types of EMS agencies. The study’s mean annual rate of turnover was lower than expected based on information appearing in the news media and EMS trade magazines. Findings

  11. Turnover among healthcare professionals.

    Science.gov (United States)

    Wood, Ben D

    2009-01-01

    Turnover among healthcare professionals is a costly consequence. The existing body of knowledge on healthcare professional turnover is correlated with job satisfaction levels. A landmark study differentiated 2 areas of job satisfaction categories: satisfiers and dissatisfiers (intrinsic and extrinsic motivators). The aim of this article is to examine existing research on precursors of turnover, such as burnout behaviors experienced by healthcare professionals, job satisfaction levels, employee organizational commitment, health complications which precede turnover, some current strategies to reduce turnover, and some effects CEO turnover has on employee turnover intentions.

  12. Global turnover of histone post-translational modifications and variants in human cells

    Directory of Open Access Journals (Sweden)

    Zee Barry M

    2010-12-01

    Full Text Available Abstract Background Post-translational modifications (PTMs on the N-terminal tails of histones and histone variants regulate distinct transcriptional states and nuclear events. Whereas the functional effects of specific PTMs are the current subject of intense investigation, most studies characterize histone PTMs/variants in a non-temporal fashion and very few studies have reported kinetic information about these histone forms. Previous studies have used radiolabeling, fluorescence microscopy and chromatin immunoprecipitation to determine rates of histone turnover, and have found interesting correlations between increased turnover and increased gene expression. Therefore, histone turnover is an understudied yet potentially important parameter that may contribute to epigenetic regulation. Understanding turnover in the context of histone modifications and sequence variants could provide valuable additional insight into the function of histone replacement. Results In this study, we measured the metabolic rate of labeled isotope incorporation into the histone proteins of HeLa cells by combining stable isotope labeling of amino acids in cell culture (SILAC pulse experiments with quantitative mass spectrometry-based proteomics. In general, we found that most core histones have similar turnover rates, with the exception of the H2A variants, which exhibit a wider range of rates, potentially consistent with their epigenetic function. In addition, acetylated histones have a significantly faster turnover compared with general histone protein and methylated histones, although these rates vary considerably, depending on the site and overall degree of methylation. Histones containing transcriptionally active marks have been consistently found to have faster turnover rates than histones containing silent marks. Interestingly, the presence of both active and silent marks on the same peptide resulted in a slower turnover rate than either mark alone on that same

  13. The rate and cost of nurse turnover in Australia.

    Science.gov (United States)

    Roche, Michael A; Duffield, Christine M; Homer, Caroline; Buchan, James; Dimitrelis, Sofia

    2015-01-01

    Nurse turnover is a critical issue facing workforce planners across the globe, particularly in light of protracted and continuing workforce shortages. An ageing population coupled with the rise in complex and chronic diseases, have contributed to increased demands placed on the health system and importantly, nurses who themselves are ageing. Costs associated with nurse turnover are attracting more attention; however, existing measurements of turnover show inconsistent findings, which can be attributed to differences in study design, metrics used to calculate turnover and variations in definitions for turnover. This paper will report the rates and costs of nurse turnover across three States in Australia.

  14. Collagen turnover after tibial fractures

    DEFF Research Database (Denmark)

    Joerring, S; Krogsgaard, M; Wilbek, H

    1994-01-01

    Collagen turnover after tibial fractures was examined in 16 patients with fracture of the tibial diaphysis and in 8 patients with fracture in the tibial condyle area by measuring sequential changes in serological markers of turnover of types I and III collagen for up to 26 weeks after fracture....... The markers were the carboxy-terminal extension peptide of type I procollagen (PICP), the amino-terminal extension peptide of type III procollagen (PIIINP), and the pyridinoline cross-linked carboxy-terminal telopeptide of type I collagen (ICTP). The latter is a new serum marker of degradation of type I...... collagen. A group comparison showed characteristic sequential changes in the turnover of types I and III collagen in fractures of the tibial diaphysis and tibial condyles. The turnover of type III collagen reached a maximum after 2 weeks in both groups. The synthesis of type I collagen reached a maximum...

  15. The costs of turnover in nursing homes

    Science.gov (United States)

    Mukamel, Dana B.; Spector, William D.; Limcangco, Rhona; Wang, Ying; Feng, Zhanlian; Mor, Vincent

    2009-01-01

    Background Turnover rates in nursing homes have been persistently high for decades, ranging upwards of 100%. Objectives To estimate the net costs associated with turnover of direct care staff in nursing homes. Data and sample 902 nursing homes in California in 2005. Data included Medicaid cost reports, the Minimum Data Set (MDS), Medicare enrollment files, Census and Area Resource File (ARF). Research Design We estimated total cost functions, which included in addition to exogenous outputs and wages, the facility turnover rate. Instrumental variable (IV) limited information maximum likelihood techniques were used for estimation to deal with the endogeneity of turnover and costs. Results The cost functions exhibited the expected behavior, with initially increasing and then decreasing returns to scale. The ordinary least square estimate did not show a significant association between costs and turnover. The IV estimate of turnover costs was negative and significant (p=0.039). The marginal cost savings associated with a 10 percentage point increase in turnover for an average facility was $167,063 or 2.9% of annual total costs. Conclusion The net savings associated with turnover offer an explanation for the persistence of this phenomenon over the last decades, despite the many policy initiatives to reduce it. Future policy efforts need to recognize the complex relationship between turnover and costs. PMID:19648834

  16. Existence of life-time stable proteins in mature rats-Dating of proteins' age by repeated short-term exposure to labeled amino acids throughout age

    DEFF Research Database (Denmark)

    Bechshøft, Cecilie Leidesdorff; Schjerling, Peter; Bornø, Andreas

    2017-01-01

    In vivo turnover rates of proteins covering the processes of protein synthesis and breakdown rates have been measured in many tissues and protein pools using various techniques. Connective tissue and collagen protein turnover is of specific interest since existing results are rather diverging. Th...... living days, indicating very slow turnover. The data support the hypothesis that some proteins synthesized during the early development and growth still exist much later in life of animals and hence has a very slow turnover rate.......In vivo turnover rates of proteins covering the processes of protein synthesis and breakdown rates have been measured in many tissues and protein pools using various techniques. Connective tissue and collagen protein turnover is of specific interest since existing results are rather diverging....... The aim of this study is to investigate whether we can verify the presence of protein pools within the same tissue with very distinct turnover rates over the life-span of rats with special focus on connective tissue. Male and female Lewis rats (n = 35) were injected with five different isotopically...

  17. Effects of experimental hyperthyroidism on protein turnover in skeletal and cardiac muscle as measured by [14C]tyrosine infusion.

    Science.gov (United States)

    Carter, W J; Benjamin, W S; Faas, F H

    1982-04-15

    The effect of T3 (3,3',5-tri-iodothyronine) on protein turnover in skeletal and cardiac muscle was measured in intact rats by means of a 6 h [14C]tyrosine-infusion technique. Treatment with 25-30 micrograms of T3/100 g body wt. daily for 4-7 days increased the fractional rate of protein synthesis in skeletal muscle. Since the fractional growth rate of the muscle was decreased or unchanged, T3 treatment increased the rate of muscle protein breakdown. These findings suggest that increased protein degradation is an important factor in decreasing skeletal-muscle mass in hyperthyroidism. In contrast with skeletal muscle, T3 treatment for 7 days caused an equivalent increase in the rate of cardiac muscle growth and protein synthesis. This suggests that hyperthyroidism does not increase protein breakdown in heart muscle as it does in skeletal muscle. The failure of T3 to increase proteolysis in heart muscle may be due to a different action on the cardiac myocyte or to systemic effects of T3 which increase cardiac work.

  18. Studies on the possible role of thyroid hormone in altered muscle protein turnover during sepsis

    International Nuclear Information System (INIS)

    Hasselgren, P.O.; Chen, I.W.; James, J.H.; Sperling, M.; Warner, B.W.; Fischer, J.E.

    1987-01-01

    Five days after thyroidectomy (Tx) or sham-Tx in young male Sprague-Dawley rats, sepsis was induced by cecal ligation and puncture (CLP). Control animals underwent laparotomy and manipulation of the cecum without ligation or puncture. Sixteen hours after CLP or laparotomy, protein synthesis and degradation were measured in incubated extensor digitorum longus (EDL) and soleus (SOL) muscles by determining rate of 14 C-phenylalanine incorporation into protein and tyrosine release into incubation medium, respectively. Triiodothyronine (T3) was measured in serum and muscle tissue. Protein synthesis was reduced by 39% and 22% in EDL and SOL, respectively, 16 hours after CLP in sham-Tx rats. The response to sepsis of protein synthesis was abolished in Tx rats. Protein breakdown was increased by 113% and 68% in EDL and SOL, respectively, 16 hours after CLP in sham-Tx animals. The increase in muscle proteolysis during sepsis was blunted in hypothyroid animals and was 42% and 49% in EDL and SOL, respectively. T3 in serum was reduced by sepsis, both in Tx and sham-Tx rats. T3 in muscle, however, was maintained or increased during sepsis. Abolished or blunted response of muscle protein turnover after CLP in hypothyroid animals may reflect a role of thyroid hormones in altered muscle protein metabolism during sepsis. Reduced serum levels of T3, but maintained or increased muscle concentrations of the hormone, suggests that increased T3 uptake by muscle may be one mechanism of low T3 syndrome in sepsis, further supporting the concept of a role for thyroid hormone in metabolic alterations in muscle during sepsis

  19. The longitudinal study of turnover and the cost of turnover in emergency medical services.

    Science.gov (United States)

    Patterson, P Daniel; Jones, Cheryl B; Hubble, Michael W; Carr, Matthew; Weaver, Matthew D; Engberg, John; Castle, Nicholas

    2010-01-01

    Few studies have examined employee turnover and associated costs in emergency medical services (EMS). To quantify the mean annual rate of turnover, total median cost of turnover, and median cost per termination in a diverse sample of EMS agencies. A convenience sample of 40 EMS agencies was followed over a six-month period. Internet, telephone, and on-site data-collection methods were used to document terminations, new hires, open positions, and costs associated with turnover. The cost associated with turnover was calculated based on a modified version of the Nursing Turnover Cost Calculation Methodology (NTCCM). The NTCCM identified direct and indirect costs through a series of questions that agency administrators answered monthly during the study period. A previously tested measure of turnover to calculate the mean annual rate of turnover was used. All calculations were weighted by the size of the EMS agency roster. The mean annual rate of turnover, total median cost of turnover, and median cost per termination were determined for three categories of agency staff mix: all-paid staff, mix of paid and volunteer (mixed) staff, and all-volunteer staff. The overall weighted mean annual rate of turnover was 10.7%. This rate varied slightly across agency staffing mix (all-paid = 10.2%, mixed = 12.3%, all-volunteer = 12.4%). Among agencies that experienced turnover (n = 25), the weighted median cost of turnover was $71,613.75, which varied across agency staffing mix (all-paid = $86,452.05, mixed = $9,766.65, and all-volunteer = $0). The weighted median cost per termination was $6,871.51 and varied across agency staffing mix (all-paid = $7,161.38, mixed = $1,409.64, and all-volunteer = $0). Annual rates of turnover and costs associated with turnover vary widely across types of EMS agencies. The study's mean annual rate of turnover was lower than expected based on information appearing in the news media and EMS trade magazines. Findings provide estimates of two key

  20. Estimation of whole body protein turnover by L-[1-[sup 13]C]-leucine tracer experiment in post-viral hepatocirrhotic patients

    Energy Technology Data Exchange (ETDEWEB)

    Xinhua, Zhu; Zhenduo, Tang; Tengchang, Dai; Zongqin, Xia [Shanghai Second Medical Univ. (China)

    1993-08-01

    A constant infusion of L-[1-[sup 1]'3C]-leucine given to the subject and the plasma [sup 13]C-leucine enrichment and breath [sup 1]'3CO[sub 2] enrichment were measured with GC-MS and gas isotope ratio MS respectively. The plateau isotope enrichments reached were used to calculate the whole body protein synthesis and breakdown rates using a two pools model. 15 post-viral hepatocirrhotic patients and 6 normal adults were studied. The whole body protein synthesis and breakdown rates were both markedly increased in cirrhotic patients, with the breakdown rate higher than the synthesis rate and hence leading to a negative nitrogen balance. The changes of 7 decompensated cirrhotic patients were more severe than 8 compensated cirrhotic patients. The results suggest that the protein malnutrition and negative nitrogen balance of post-viral hepatocirrhotic patients are not simply due to low intake of protein and that the hyperactive turnover, especially the excessive breakdown of body protein might play an important role.

  1. Rapid phospho-turnover by receptor tyrosine kinases impacts downstream signaling and drug binding.

    Science.gov (United States)

    Kleiman, Laura B; Maiwald, Thomas; Conzelmann, Holger; Lauffenburger, Douglas A; Sorger, Peter K

    2011-09-02

    Epidermal growth factor receptors (ErbB1-4) are oncogenic receptor tyrosine kinases (RTKs) that regulate diverse cellular processes. In this study, we combine measurement and mathematical modeling to quantify phospho-turnover at ErbB receptors in human cells and to determine the consequences for signaling and drug binding. We find that phosphotyrosine residues on ErbB1 have half-lives of a few seconds and therefore turn over 100-1000 times in the course of a typical immediate-early response to ligand. Rapid phospho-turnover is also observed for EGF-activated ErbB2 and ErbB3, unrelated RTKs, and multiple intracellular adaptor proteins and signaling kinases. Thus, the complexes formed on the cytoplasmic tail of active receptors and the downstream signaling kinases they control are highly dynamic and antagonized by potent phosphatases. We develop a kinetic scheme for binding of anti-ErbB1 drugs to receptors and show that rapid phospho-turnover significantly impacts their mechanisms of action. Copyright © 2011 Elsevier Inc. All rights reserved.

  2. Regulation of Hxt3 and Hxt7 turnover converges on the Vid30 complex and requires inactivation of the Ras/cAMP/PKA pathway in Saccharomyces cerevisiae.

    Directory of Open Access Journals (Sweden)

    Chris Snowdon

    Full Text Available Eukaryotic cells adjust their intracellular protein complement as a mechanism to adapt to changing environmental signals. In Saccharomyces cerevisiae the hexose transporters Hxt3 and Hxt7 are expressed and function on the plasma membrane in high and low glucose abundance, respectively. By contrast, Hxt3 is endocytosed and degraded in the vacuole when cells are starved of glucose and Hxt7 in response to rapamycin treatment or when nitrogen is limiting. Yeast uses several signaling pathways, including the TORC1 and Ras/cAMP/Protein Kinase A (PKA pathways, to adapt to nutrient changes in the environment. The multi-protein Vid30 complex (Vid30c, an E3 ubiquitin ligase required for the degradation of FBPase, assists in this adaptation process in a mechanism that is poorly understood. Here we show the endocytosis and the subsequent degradation of both Hxt3 and Hxt7, in response to different nutrient signals, is dependent on components of the Vid30c. Additionally, we define the signaling events required for the turnover of Hxt3 and Hxt7 by showing that Hxt3 turnover requires Ras2 and PKA inactivation, whereas Hxt7 turnover requires TORC1 and Ras2 inactivation. Further investigation led us to identify Rim15, a kinase that is inhibited by both the TORC1 and Ras/cAMP/PKA pathways, as a key downstream effector in signaling both turnover events. Finally, we show that the turnover of both Hxt3 and Hxt7 is dependent on the essential E3 ubiquitin ligase, Rsp5, indicating that the role of the Vid30c might be indirect of Hxt ubiquitylation.

  3. Does public service performance affect top management turnover?

    OpenAIRE

    Boyne, George A.; James, Oliver; John, Peter; Petrovsky, Nicolai

    2010-01-01

    Political and organizational theories suggest that the turnover of chief executives and other members of senior management teams are likely to be influenced by public service performance. We use a panel data set of 148 English local governments over 4 years to test this proposition. The empirical results show that performance has a negative effect on turnover, but that this effect is weaker for chief executives than for members of their senior management teams. In addition, top team turnover ...

  4. Investigating the adequacy of the Competence-Turnover Intention Model: how does nursing competence affect nurses' turnover intention?

    Science.gov (United States)

    Takase, Miyuki; Teraoka, Sachiko; Kousuke, Yabase

    2015-03-01

    The aim of this study was to test the adequacy of the Competence-Turnover Intention Model, which was developed to identify how nursing competence could affect nurses' turnover intention (nurses' intention to voluntarily leave an organisation). Recent studies have suggested that the level of nursing competence is negatively related to nurses' intention to leave their jobs, suggesting that a lack of competence threatens both the quality and quantity of the nursing workforce. However, the mechanism of how nursing competence affects nurses' turnover intention has not been explored previously. A cross-sectional survey design was used. Surveys were distributed to 1337 Japanese registered nurses/midwives in October, 2013. The adequacy of the model was analysed using structural equation modelling. In total, 766 questionnaires were returned, with a return rate of 57%. The model fitted well with the data. The results showed that the level of nursing competence was related positively to the quantity of organisational rewards they felt they had received, and negatively related to the level of exhaustion they experienced. Moreover, the perceived organisational rewards and exhaustion were correlated with nurses' turnover intention through affective commitment. The Competence-Turnover Intention Model is useful for explaining how nursing competence impacts on their turnover intention. Clinical implications derived from the findings are that: promoting nursing competence is key to improving not only the quality of care provided by nurses, but also to retaining the nursing workforce, and the model can be used to develop strategies that would mitigate their turnover intention. © 2014 John Wiley & Sons Ltd.

  5. Investing in Leadership: The District's Role in Managing Principal Turnover

    Science.gov (United States)

    Mascall, Blair; Leithwood, Kenneth

    2010-01-01

    This article presents the results of research into the impact of principal turnover on schools, and the ability of schools to mitigate the negative effects of frequent turnover by distributing leadership in the schools. The findings from this qualitative and quantitative analysis show that rapid principal turnover does indeed have a negative…

  6. Turnover of Biogenic Amines in the Hypothalamus of Rats during Pyrogen Fever

    Science.gov (United States)

    Penn, P. E.; Williams, B. A.

    1979-01-01

    Many pharmacological studies have implicated the biogenic amines in the hypothalamus as playing a role in the production of fever, but few investigations of endogenous neurochemicals have been made during fever. Turnover rates of transmitters utilizing radioactive precursors may be one of the most accurate measurements of activity in brain regions. The present study was designed to measure the turnover of 5-hydroxytryptamine (5-HT) norepinephrine (NE) and dopamine (DA) in the hypothalamus of rats during pyrogen fever. Salmonella typhosa (Wyeth, 8 units) was previously found in our laboratory to produce a significant hyperthermia in most rats by 2.5 hours. This pyrogen (N = l2) or saline control (N = 8) was injected intraperitoneally and the rats killed 2.75 hours later. Rectal temperatures (Tr) were monitored continuously with thermocouples taped to the tail and recorded automatically every 3 minutes. Half of each group received an injection of radioactive precursors, (3)H-tryptophan (0.5 mCi) and (3)H-tryptophan (1.0 mCi), via an indwelling jugular catheter 60 minutes before killing, and the other half at 90 minutes. The rats were killed by near freezing in liquid nitrogen and the brains dissected in the cold. Turnover was measured by the method of Lane (Life Sci 21, 1101, 1977). At the time of killing most of the pyrogen group showed a significant (p pyrogen and saline groups. A significant difference was found in the specific activity of NE between the 60 minute pyrogen and saline groups (4.41 +/- 0.41 vs 2.6 +/- 0.51 dpm/pmole) but no change in turnover. This suggests an increased accumulation of (3)H-NE in the pyrogen group, but no change in utilization. An increased turnover of DA for the pyrogen group (44.5 vs 19.2 pmole/mg protein/hr) was found. However, DA is mainly a precursor in the hypothalamus and measurement was near the limit of sensitivity for the assay; these limitations Must be considered in interpreting this data. The most significant finding was

  7. The Influence of Dietary Habits and Meat Consumption on Plasma 3‐Methylhistidine—A Potential Marker for Muscle Protein Turnover

    Science.gov (United States)

    Kochlik, Bastian; Gerbracht, Christiana; Grune, Tilman

    2018-01-01

    Scope 3‐Methylhistidine (3‐MH) as a potential biomarker for muscle protein turnover is influenced by meat intake but data on the impact of meat on plasma 3‐MH are scarce. We determined the association of plasma 3‐MH, 1‐methylhistidine (1‐MH), and creatinine with dietary habits and assessed the impact of a single white meat intervention during a meat‐free period. Methods and results Plasma 3‐MH, 1‐MH, and creatinine concentrations of healthy young omnivores (n = 19) and vegetarians (n = 16) were analyzed together with data on anthropometry, body composition, grip strength, and nutrition. After baseline measurements omnivores adhered to a meat‐free diet for 6 days and received a defined administration of chicken breast on day four. At baseline, omnivores had higher plasma 3‐MH and 1‐MH concentrations than vegetarians. White meat administration led to a slight increase in plasma 3‐MH in omnivores. The elevated 3‐MH concentrations significantly declined within 24 h after white meat intake. Conclusion 1‐MH concentrations in plasma seem to be suitable to display (white) meat consumption and its influence on 3‐MH plasma concentration. 3‐MH in plasma may be used as a biomarker for muscle protein turnover if subjects have not consumed meat in the previous 24 h. PMID:29573154

  8. 'Memory and molecular turnover,' 30 years after inception.

    Science.gov (United States)

    Meagher, Richard B

    2014-01-01

    In 1984 Sir Francis Crick hypothesized that memory is recorded in the brain as reversible modifications to DNA and protein, but acknowledged that most biomolecules turn over too rapidly to account for long-term memories. To accommodate this possible paradox he modeled an enzymatic mechanism to maintain modifications on hemi-modified multimeric symmetrical molecules. While studies on the turnover of chromatin modifications that may be involved in memory are in their infancy, an exploration of his model in the light of modern epigenetics produced somewhat surprising results. The molecular turnover rates for two classes of chromatin modifications believed to record and store durable memories were approximated from experiments using diverse approaches and were found to be remarkably short. The half-lives of DNA cytosine methylation and post-translationally modified nucleosomal histones are measured in hours and minutes, respectively, for a subset of sites on chromatin controlling gene expression. It appears likely that the turnover of DNA methylation in the brain and in neurons, in particular, is even more rapid than in other cell types and organs, perhaps accommodating neuronal plasticity, learning, and memory. The machinery responsible for the rapid turnover of DNA methylation and nucleosomal histone modifications is highly complex, partially redundant, and appears to act in a sequence specific manner. Molecular symmetry plays an important part in maintaining site-specific turnover, but its particular role in memory maintenance is unknown. Elucidating Crick's paradox, the contradiction between rapid molecular turnover of modified biomolecules and long-term memory storage, appears fundamental to understanding cognitive function and neurodegenerative disease.

  9. Acid phosphatase turnover during repressed and derepressed cultivation of Aspergillus niger

    International Nuclear Information System (INIS)

    Komano, Teruya

    1975-01-01

    Enhancement of the activity of acid phosphatase (EC 3.1.3.2) by phosphate starvation in growing Aspergillus niger mycelia was prevented by cycloheximide. This indicates that the enhancement was due to de novo protein synthesis caused by derepression. Radioactive acid phosphatase extracted from mycelia labeled with 14 C-amino acid was separated into at least four fractions. Experiments on pulse labeling and the chasing of the four acid phosphatases revealed the synthesis and degradation of each fraction occurred at different rates; showing a different rate of turnover of the enzyme molecules. The results of similar experiments performed during culture in the presence of phosphate (partially repressed condition) suggested that the marked change in the activity ratios of the four acid phosphatases during cultivation was the result of the active turnover of enzyme molecules. In contrast, the slight changes in the ratios observed during derepressed cultivation seemed to be the result of similar of synthesis and degradation of each phosphatase fraction. (auth.)

  10. Role of a redox-based methylation switch in mRNA life cycle ( pre- & post- transcriptional maturation and protein turnover : Implications in neurological disorders

    Directory of Open Access Journals (Sweden)

    MALAV SUCHIN TRIVEDI

    2012-06-01

    Full Text Available Homeostatic synaptic scaling in response to neuronal stimulus or activation, as well as due to changes in cellular niche, is an important phenomenon for memory consolidation, retrieval, and other similar cognitive functions. Neurological disorders and cognitive disabilities in autism, Rett syndrome, schizophrenia, dementia etc., are strongly correlated to alterations in protein expression (both synaptic and cytoplasmic. This correlation suggests that efficient temporal regulation of synaptic protein expression is important for synaptic plasticity. In addition, equilibrium between mRNA processing, protein translation and protein turnover is a critical sensor/trigger for recording synaptic information, normal cognition and behavior. Thus a regulatory switch, controlling the lifespan, maturation and processing of mRNA, might influence cognition and adaptive behavior. Here, we propose a two part novel hypothesis that methylation might act as this suggested coordinating switch to critically regulate mRNA maturation at 1.The pre-transcription level, by regulating precursor-RNA (pre-RNA processing into mRNA, via other non-coding RNAs and their influence on splicing phenomenon, and 2. the post-transcription level by modulating the regulatory functions of ribonucleoproteins (RNP and RNA binding proteins (RNABP in mRNA translation, dendritic translocation as well as protein synthesis and synaptic turnover. DNA methylation changes are well recognized and highly correlated to gene expression levels as well as, learning and memory; however, RNA methylation changes are recently characterized and yet their functional implications are not established. This review article provides some insight on the intriguing consequences of changes in methylation levels on mRNA life-cycle. We also suggest that, since methylation is under the control of glutathione antioxidant levels, the redox status of neurons might be the central regulatory switch for methylation

  11. PERAN STRES KERJA DAN KEPUASAN KERJA UNTUK MENGURANGI TURNOVER INTENTION

    Directory of Open Access Journals (Sweden)

    Syarifah Nazenin

    2014-09-01

    Full Text Available Tujuan penelitian ini untuk menguji pengaruh variabel stres kerja dan kepuasan kerja pada turnover intention karyawan tetap bagian produksi. Sampel penelitian ini adalah 86 responden, menggunakan metode Slovin dengan teknik probability sampling dengan jenis proportionate random sampling. Berdasarkan hasil penelitian, menunjukkan bahwa stres kerja berpengaruh positif signifikan pada turnover intention. Kemudian, kepuasan kerja berpengaruh negatif signifikan. Penelitian ini menyimpulkan, bahwa stres kerja berpengaruh positif dan signifikan pada turnover intention karyawan dan kepuasan kerja berpengaruh negatif dan signifikan terhadap turnover intention karyawan. Implikasi manajerial yang bisa dilakukan adalah dengan pengurangan tingkat stres karyawan dan membuat program untuk tujuan menekan turnover intention, seperti kesempatan promosi dan meningkatkan reward karyawan. The purpose of this study conducted to examine the effect of work stress and job satisfaction on turnover intention of employee in production department. The sample was 86 respondent, using Slovin method with proportionate random sampling technique. The result showed that job stress has a positive effect on turnover intention while job satisfaction has a negative effect on turnover intention. This study conclude that job stress has positive and significant impact on employee turnover intention and job satisfaction significantly and negatively related to turnover intention of employees. Therefore, it is recommended to managerial level people to reduce stress levels in employees and to create a program for pressing turnover intention, such as promotional opportunities and improve employee rewards.

  12. The HIV1 protein Vpr acts to enhance constitutive DCAF1-dependent UNG2 turnover.

    Directory of Open Access Journals (Sweden)

    Xiaoyun Wen

    Full Text Available The HIV1 protein Vpr assembles with and acts through an ubiquitin ligase complex that includes DDB1 and cullin 4 (CRL4 to cause G2 cell cycle arrest and to promote degradation of both uracil DNA glycosylase 2 (UNG2 and single-strand selective mono-functional uracil DNA glycosylase 1 (SMUG1. DCAF1, an adaptor protein, is required for Vpr-mediated G2 arrest through the ubiquitin ligase complex. In work described here, we used UNG2 as a model substrate to study how Vpr acts through the ubiquitin ligase complex. We examined whether DCAF1 is essential for Vpr-mediated degradation of UNG2 and SMUG1. We further investigated whether Vpr is required for recruiting substrates to the ubiquitin ligase or acts to enhance its function and whether this parallels Vpr-mediated G2 arrest.We found that DCAF1 plays an important role in Vpr-independent UNG2 and SMUG1 depletion. UNG2 assembled with the ubiquitin ligase complex in the absence of Vpr, but Vpr enhanced this interaction. Further, Vpr-mediated enhancement of UNG2 degradation correlated with low Vpr expression levels. Vpr concentrations exceeding a threshold blocked UNG2 depletion and enhanced its accumulation in the cell nucleus. A similar dose-dependent trend was seen for Vpr-mediated cell cycle arrest.This work identifies UNG2 and SMUG1 as novel targets for CRL4(DCAF1-mediated degradation. It further shows that Vpr enhances rather than enables the interaction between UNG2 and the ubiquitin ligase. Vpr augments CRL4(DCAF1-mediated UNG2 degradation at low concentrations but antagonizes it at high concentrations, allowing nuclear accumulation of UNG2. Further, the protein that is targeted to cause G2 arrest behaves much like UNG2. Our findings provide the basis for determining whether the CRL4(DCAF1 complex is alone responsible for cell cycle-dependent UNG2 turnover and will also aid in establishing conditions necessary for the identification of additional targets of Vpr-enhanced degradation.

  13. Protein turnover and cellular stress in mildly and severely affected muscles from patients with limb girdle muscular dystrophy type 2I.

    Directory of Open Access Journals (Sweden)

    Simon Hauerslev

    Full Text Available Patients with Limb girdle muscular dystrophy type 2I (LGMD2I are characterized by progressive muscle weakness and wasting primarily in the proximal muscles, while distal muscles often are spared. Our aim was to investigate if wasting could be caused by impaired regeneration in the proximal compared to distal muscles. Biopsies were simultaneously obtained from proximal and distal muscles of the same patients with LGMD2I (n = 4 and healthy subjects (n = 4. The level of past muscle regeneration was evaluated by counting internally nucleated fibers and determining actively regenerating fibers by using the developmental markers embryonic myosin heavy chain (eMHC and neural cell adhesion molecule (NCAM and also assessing satellite cell activation status by myogenin positivity. Severe muscle histopathology was occasionally observed in the proximal muscles of patients with LGMD2I whereas distal muscles were always relatively spared. No difference was found in the regeneration markers internally nucleated fibers, actively regenerating fibers or activation status of satellite cells between proximal and distal muscles. Protein turnover, both synthesis and breakdown, as well as cellular stress were highly increased in severely affected muscles compared to mildly affected muscles. Our results indicate that alterations in the protein turnover and myostatin levels could progressively impair the muscle mass maintenance and/or regeneration resulting in gradual muscular atrophy.

  14. Collagen turnover in normal and degenerate human intervertebral discs as determined by the racemization of aspartic acid

    NARCIS (Netherlands)

    Sivan, S.-S.; Wachtel, E.; Tsitron, E.; Sakkee, N.; Ham, F. van der; Groot, J.de; Roberts, S.; Maroudas, A.

    2008-01-01

    Knowledge of rates of protein turnover is important for a quantitative understanding of tissue synthesis and catabolism. In this work, we have used the racemization of aspartic acid as a marker for the turnover of collagen obtained from healthy and pathological human intervertebral disc matrices. We

  15. Regulation of Nur77 protein turnover through acetylation and deacetylation induced by p300 and HDAC1.

    Science.gov (United States)

    Kang, Shin-Ae; Na, Hyelin; Kang, Hyun-Jin; Kim, Sung-Hye; Lee, Min-Ho; Lee, Mi-Ock

    2010-09-15

    Although the roles of Nur77, an orphan member of the nuclear hormone receptor superfamily, in the control of cellular proliferation, apoptosis, inflammation, and glucose metabolism, are well recognized, the molecular mechanism regulating the activity and expression of Nur77 is not fully understood. Acetylation of transcription factors has emerged recently as a major post-translational modification that regulates protein stability and transcriptional activity. Here, we examined whether Nur77 is acetylated, and we characterized potential associated factors. First, Nur77 was found to be an acetylated protein when examined by immunoprecipitation and western blotting using acetyl protein-specific antibodies. Second, expression of p300, which possesses histone acetyltransferase activity, enhanced the acetylation and protein stability of Nur77. Treatment with a histone deacetylase (HDAC) inhibitor, trichostatin A, also increased Nur77 acetylation. Among the several types of HDACs, HDAC1 was found as the major enzyme affecting protein level of Nur77. HDAC1 decreased the acetylation level, protein level, and transcriptional activity of Nur77. Interestingly, overexpression of Nur77 induced expression of both p300 and HDAC1. Finally, the expression of Nur77 increased along with that of p300, but decreased with induction of HDAC1 after treatment with epithelial growth factor, nerve growth factor, or 6-mercaptopurine, suggesting that the self-control of the acetylation status contributes to the transient induction of Nur77 protein. Taken together, these results demonstrate that acetylation of Nur77 is modulated by p300 and HDAC1, and suggest that acetylation is an important post-translational modification for the rapid turnover of Nur77 protein. Copyright 2010 Elsevier Inc. All rights reserved.

  16. Hospital Mergers in Norway: Employee Health and Turnover to Three Destinations

    Directory of Open Access Journals (Sweden)

    Mari Holm Ingelsrud

    2017-03-01

    Full Text Available This article investigates the probability of turnover to three destinations following hospital merg- ers: within the hospital sector, out of the hospital sector, and out of work. It is hypothesized that mergers increase turnover to nonemployment among employees with poor health and increase turnover to employment outside of the hospital sector among healthy employees. Discrete-time survival analyses show that mergers increase turnover within the hospital sector for all employ- ees, regardless of health. Turnover to other sectors and out of work does not increase. Possible explanations for the limited turnover out of the sector associated with mergers are aspects of the Norwegian labor market such as the institution of employee participation, low unemployment, and labor shortages within hospitals.

  17. Mentor program boosts new nurses' satisfaction and lowers turnover rate.

    Science.gov (United States)

    Fox, Kathy C

    2010-07-01

    In 2004, the turnover rate among first-year registered nurses (RNs) at St. Francis Hospital and Health Centers had mushroomed to 31%. Based on research, in 2006, the hospital embarked on a journey to implement an RN mentor program to improve satisfaction and reduce turnover. A pilot program was initiated, including 12 RN mentors and 12 RN protégés from select nursing units. The results showed a 0% turnover rate during the 1-year pilot program. Based on these findings, the mentor program was expanded to include RNs working in inpatient nursing units and surgery and emergency departments. Each year, the RN turnover rate has decreased. In 2009, the turnover rate was 10.3%. Because of the success of the program, it has been expanded in scope to include other professionals experiencing high turnover in targeted departments, including radiological technicians, respiratory therapists, pharmacists, and physical therapists.

  18. Predictors of Staff Turnover and Turnover Intentions within Addiction Treatment Settings: Change Over Time Matters.

    Science.gov (United States)

    Garner, Bryan R; Hunter, Brooke D

    2014-01-01

    This study examined the extent to which changes over time in clinicians' responses to measures of work attitude (eg, job satisfaction) and psychological climate (eg, supervisor support) could predict actual turnover and turnover intentions above and beyond absolute levels of these respective measures. Longitudinal data for this study were collected from a sample of clinicians (N = 96) being trained to implement an evidence-based treatment for adolescent substance use disorders. Supporting findings from a recent staff turnover study, we found job satisfaction change was able to predict actual turnover above and beyond average levels of job satisfaction. Representing new contributions to the staff turnover literature, we also found that change over time in several other key measures (eg, job satisfaction, role manageability, role clarity) explained a significant amount of variance in turnover intentions above and beyond the absolute level of each respective measure. A key implication of the current study is that organizations seeking to improve their ability to assess risk for staff turnover may want to consider assessing staff at multiple points in time in order to identify systematic changes in key employee attitudes like turnover intentions and job satisfaction.

  19. Predictors of Staff Turnover and Turnover Intentions within Addiction Treatment Settings: Change over Time Matters

    Directory of Open Access Journals (Sweden)

    Bryan R. Garner

    2014-01-01

    Full Text Available This study examined the extent to which changes over time in clinicians’ responses to measures of work attitude (eg, job satisfaction and psychological climate (eg, supervisor support could predict actual turnover and turnover intentions above and beyond absolute levels of these respective measures. Longitudinal data for this study were collected from a sample of clinicians ( N = 96 being trained to implement an evidence-based treatment for adolescent substance use disorders. Supporting findings from a recent staff turnover study, we found job satisfaction change was able to predict actual turnover above and beyond average levels of job satisfaction. Representing new contributions to the staff turnover literature, we also found that change over time in several other key measures (eg, job satisfaction, role manageability, role clarity explained a significant amount of variance in turnover intentions above and beyond the absolute level of each respective measure. A key implication of the current study is that organizations seeking to improve their ability to assess risk for staff turnover may want to consider assessing staff at multiple points in time in order to identify systematic changes in key employee attitudes like turnover intentions and job satisfaction.

  20. PENGARUH KEPUASAN KERJA TERHADAP KOMITMEN ORGANISASI DAN TURNOVER INTENTION

    Directory of Open Access Journals (Sweden)

    Agi Syarif Hidayat

    2018-03-01

    Full Text Available The high level of employee turnover in the marketing department at PT. Toyamilindo indicates low organizational commitment and high turnover intention. The purpose of this study is to determine the effect of job satisfaction on organizational commitment and turnover intention. Quantitative methods are used in this study. Population is the  employees of marketing department at PT. Toyamilindo with 50 people. Sampling technique used is sampling saturated with the number of samples of 50 people. Data collection technique uses questionnaires and regression analysis. Finding on the research results shows that there are positive and significant influence of job satisfaction on organizational commitment and negative and significant influence of job satisfaction on turnover intention, and also the influence of organizational commitment on work satisfaction to turnover intention. The managerial implications of corporate leaders must improve employee work satisfaction, especially in terms of salary.

  1. KECENDERUNGAN KEPUASAN KERJA SEBAGAI TRIGGER TURNOVER

    Directory of Open Access Journals (Sweden)

    Raditya Adi Saputra

    2017-06-01

    Full Text Available The purpose of this study are: (1 To determine the effect of job satisfaction on turnover intention; (2 To determine the effect of work stress on turnover intention; (3 To determine the effect of compensation on turnover intention; (4 To determine the effect of organizational climate on turnover intention; and (5 To determine the stress of work, compensation, organizational climate and job satisfaction effect on turnover intention. The population in this study are employees of the Cooperative KOKAPURA AVIA totaling 180 people, while employees who have worked more than three years as many as 128 people. Samples were taken 97 people. The technique of collecting data using questionnaires. The analysis used is multiple regression analysis and path analysis using PLS 3.0 Smart program. Based on the results of the study concluded that: (1 Job satisfaction significantly influence employee turnover intention; (2 Work stress significantly influence employee turnover intention; (3 Compensation incentives significantly influence employee turnover intention; (4 organizational climate significantly influence employee turnover intention; and (5 Work stress, incentive compensation, organizational climate and job satisfaction simultaneously significantly influence employee turnover intention.

  2. Radiocarbon Dating of the Human Eye Lens Crystallines Reveal Proteins without Carbon Turnover throughout Life

    Science.gov (United States)

    Lynnerup, Niels; Kjeldsen, Henrik; Heegaard, Steffen; Jacobsen, Christina; Heinemeier, Jan

    2008-01-01

    Background Lens crystallines are special proteins in the eye lens. Because the epithelial basement membrane (lens capsule) completely encloses the lens, desquamation of aging cells is impossible, and due to the complete absence of blood vessels or transport of metabolites in this area, there is no subsequent remodelling of these fibers, nor removal of degraded lens fibers. Human tissue ultimately derives its 14C content from the atmospheric carbon dioxide. The 14C content of the lens proteins thus reflects the atmospheric content of 14C when the lens crystallines were formed. Precise radiocarbon dating is made possible by comparing the 14C content of the lens crystallines to the so-called bomb pulse, i.e. a plot of the atmospheric 14C content since the Second World War, when there was a significant increase due to nuclear-bomb testing. Since the change in concentration is significant even on a yearly basis this allows very accurate dating. Methodology/Principal Findings Our results allow us to conclude that the crystalline formation in the lens nucleus almost entirely takes place around the time of birth, with a very small, and decreasing, continuous formation throughout life. The close relationship may be further expressed as a mathematical model, which takes into account the timing of the crystalline formation. Conclusions/Significance Such a life-long permanence of human tissue has hitherto only been described for dental enamel. In confront to dental enamel it must be held in mind that the eye lens is a soft structure, subjected to almost continuous deformation, due to lens accommodation, yet its most important constituent, the lens crystalline, is never subject to turnover or remodelling once formed. The determination of the 14C content of various tissues may be used to assess turnover rates and degree of substitution (for example for brain cell DNA). Potential targets may be nervous tissues in terms of senile or pre-senile degradation, as well as other highly

  3. Radiocarbon dating of the human eye lens crystallines reveal proteins without carbon turnover throughout life.

    Directory of Open Access Journals (Sweden)

    Niels Lynnerup

    Full Text Available BACKGROUND: Lens crystallines are special proteins in the eye lens. Because the epithelial basement membrane (lens capsule completely encloses the lens, desquamation of aging cells is impossible, and due to the complete absence of blood vessels or transport of metabolites in this area, there is no subsequent remodelling of these fibers, nor removal of degraded lens fibers. Human tissue ultimately derives its (14C content from the atmospheric carbon dioxide. The (14C content of the lens proteins thus reflects the atmospheric content of (14C when the lens crystallines were formed. Precise radiocarbon dating is made possible by comparing the (14C content of the lens crystallines to the so-called bomb pulse, i.e. a plot of the atmospheric (14C content since the Second World War, when there was a significant increase due to nuclear-bomb testing. Since the change in concentration is significant even on a yearly basis this allows very accurate dating. METHODOLOGY/PRINCIPAL FINDINGS: Our results allow us to conclude that the crystalline formation in the lens nucleus almost entirely takes place around the time of birth, with a very small, and decreasing, continuous formation throughout life. The close relationship may be further expressed as a mathematical model, which takes into account the timing of the crystalline formation. CONCLUSIONS/SIGNIFICANCE: Such a life-long permanence of human tissue has hitherto only been described for dental enamel. In confront to dental enamel it must be held in mind that the eye lens is a soft structure, subjected to almost continuous deformation, due to lens accommodation, yet its most important constituent, the lens crystalline, is never subject to turnover or remodelling once formed. The determination of the (14C content of various tissues may be used to assess turnover rates and degree of substitution (for example for brain cell DNA. Potential targets may be nervous tissues in terms of senile or pre

  4. Pengaruh Budaya Organisasi dan Gaya Kepemimpinan Transformasional terhadap Intensi Turnover Karyawan

    OpenAIRE

    Ginting, Artiwinata

    2016-01-01

    This study aims to determine the influence of organization culture and transformational leadership style toward to employee turnover intention. Data were collected by using employee turnover intention scale, organization culture scale and transformational leadership style scale. This research involved 206 employees. The results showed that organization culture and transformational leadership style not significant influenced to employee turnover intention. The organizational culture negatively...

  5. Understanding the factors that determine registered nurses' turnover intentions.

    Science.gov (United States)

    Osuji, Joseph; Uzoka, Faith-Michael; Aladi, Flora; El-Hussein, Mohammed

    2014-01-01

    Turnover among registered nurses (RNs) produces a negative impact on the health outcomes of any health care organization. It is also recognized universally as a problem in the nursing profession. Little is known about the turnover intentions and career orientations of RNs working in Calgary, Alberta, Canada. The aim of this study is to contribute to the knowledge of and to advance the discussion on the turnover of nursing professionals. The study population consisted of RNs employed in the five major hospitals in Calgary. There were 193 surveys returned, representing a response rate of 77.2%. The results show that age and education have a negative effect on turnover intention. Education was found to have a significant negative effect on career satisfaction but not on job satisfaction and organizational commitment. Length of service has a significant negative effect on turnover intention. Role ambiguity has significant highly negative effect on career satisfaction. Growth opportunity and supervisor support have a very significant positive effect on job satisfaction, career satisfaction, and organizational commitment. External career opportunities and organizational commitment do not seem to have a significant effect on turnover intention. Career satisfaction, on the other hand, had negative significant effects on turnover intention.

  6. Analysis and control of employee turnover.

    Science.gov (United States)

    McConnell, Charles R

    2007-01-01

    Turnover is a relatively simple and easily described concept. However, considerable confusion often results when addressing turnover because of differences in how it is defined; that is, what is counted, how it is counted, and how the turnover rates are expressed. Turnover is also costly, although not enough attention is paid to its cost because so much of it is indirect, and thus, not readily visible. There are a variety of causes of turnover, some which can be corrected and some which cannot be avoided. Reducing or otherwise controlling turnover requires continuing management attention to its causes and constant recognition of what can and should be controlled and what cannot be controlled. Ongoing attention to turnover is an essential part of the department manager's role.

  7. Uptake and degradation of circulating proteins by the liver.

    NARCIS (Netherlands)

    Buys, Carolus Henricus Cornelis Maria

    1976-01-01

    Circulating proteins, like all proteins in a living animal, are subject to continual replacement or turnover. This process implies both synthesis and degradation, This thesis deals with the degradative part of turnover of circulating proteins. ... Summary

  8. An Integrative Literature Review of Patient Turnover in Inpatient Hospital Settings.

    Science.gov (United States)

    Park, Shin Hye; Weaver, Lindsay; Mejia-Johnson, Lydia; Vukas, Rachel; Zimmerman, Julie

    2016-05-01

    High patient turnover can result in fragmentation of nursing care. It can also increase nursing workload and thus impede the ability of nurses to provide safe and high-quality care. We reviewed 20 studies that examined patient turnover in relation to nursing workload, staffing, and patient outcomes as well as interventions in inpatient hospital settings. The studies consistently addressed the importance of accounting for patient turnover when estimating nurse staffing needs. They also showed that patient turnover varied by time, day, and unit type. Researchers found that higher patient turnover was associated with adverse events; however, further research on this topic is needed because evidence on the effect of patient turnover on patient outcomes is not yet strong and conclusive. We suggest that researchers and administrators need to pay more attention to patterns and levels of patient turnover and implement managerial strategies to reduce nursing workload and improve patient outcomes. © The Author(s) 2015.

  9. Business Ethics & Employee Turnover: CAFE Matrix

    OpenAIRE

    Sapovadia, Vrajlal; Patel, Sweta

    2013-01-01

    Abstract: Business ethics is in discussion for its importance universally, so is the employee turnover in business. Unethical practices are unwanted, so is the high employee turnover. Unethical practices and high employee turnover in business is ubiquitous. No consensus exists on defining ethics. Employee turnover is well defined, but there is no consensus on when employee turnover is disadvantageous for the company. The Golden Rule or ethic of reciprocity, a maxim states that either ...

  10. The excretion of isotope in urea and ammonia for estimating protein turnover in man with [15N]glycine

    International Nuclear Information System (INIS)

    Fern, E.B.; Garlick, P.J.; McNurlan, M.A.; Waterlow, J.C.

    1981-01-01

    Four normal adults were given [ 15 N]-glycine in a single dose either orally or intravenously. Rates of whole-body protein turnover were estimated from the excretion of 15 N in ammonia and in urea during the following 9 h. The rate derived from urea took account of the [ 15 N]urea retained in body water. In postabsorptive subjects the rates of protein synthesis given by ammonia were equal to those from urea, when the isotope was given orally, but lower when an intravenous dose was given. In subjects receiving equal portions of food every 2 h rates of synthesis calculated from ammonia were much lower than those from urea whether an oral or intravenous isotope was given. Comparison of rates obtained during the postabsorptive and absorptive periods indicated regulation by food intake primarily of synthesis when measurements were made on urea, but regulation primarily of breakdown when measurements were made on ammonia. These inconsistencies suggest that changes in protein metabolism might be assessed better by correlating results given by different end-products, and it is suggested that the mean value given by urea and ammonia will be useful for this purpose. (author)

  11. Excretion of isotope in urea and ammonia for estimating protein turnover in man with (/sup 15/N)glycine

    Energy Technology Data Exchange (ETDEWEB)

    Fern, E B; Garlick, P J; McNurlan, M A; Waterlow, J C [London School of Hygiene and Tropical Medicine (UK)

    1981-01-01

    Four normal adults were given (/sup 15/N)-glycine in a single dose either orally or intravenously. Rates of whole-body protein turnover were estimated from the excretion of /sup 15/N in ammonia and in urea during the following 9 h. The rate derived from urea took account of the (/sup 15/N)urea retained in body water. In postabsorptive subjects the rates of protein synthesis given by ammonia were equal to those from urea, when the isotope was given orally, but lower when an intravenous dose was given. In subjects receiving equal portions of food every 2 h rates of synthesis calculated from ammonia were much lower than those from urea whether an oral or intravenous isotope was given. Comparison of rates obtained during the postabsorptive and absorptive periods indicated regulation by food intake primarily of synthesis when measurements were made on urea, but regulation primarily of breakdown when measurements were made on ammonia. These inconsistencies suggest that changes in protein metabolism might be assessed better by correlating results given by different end-products, and it is suggested that the mean value given by urea and ammonia will be useful for this purpose.

  12. Antigen-driven T-cell turnover

    NARCIS (Netherlands)

    Fraser, Christophe; Ferguson, Neil M.; de Wolf, Frank; Ghani, Azra C.; Garnett, Geoff P.; Anderson, Roy M.

    2002-01-01

    A mathematical model is developed to characterize the distribution of cell turnover rates within a population of T lymphocytes. Previous models of T-cell dynamics have assumed a constant uniform turnover rate; here we consider turnover in a cell pool subject to clonal proliferation in response to

  13. Docosahexaenoate-containing molecular species of glycerophospholipids from frog retinal rod outer segments show different rates of biosynthesis and turnover

    International Nuclear Information System (INIS)

    Louie, K.; Wiegand, R.D.; Anderson, R.E.

    1988-01-01

    The authors have studied the de novo synthesis and subsequent turnover of major docosahexaenoate-containing molecular species in frog rod outer segment (ROS) phospholipids following intravitreal injection of [2- 3 H]glycerol. On selected days after injection, ROS were prepared and phospholipids extracted. Phosphatidylcholine (PC), phosphatidylethanolamine (PE), and phosphatidylserine (PS) were isolated and converted to diradylglycerols with phospholipase C. Diradylglycerols were derivatized with benzoic anhydride and resolve into diacylglycerobenzoates and ether-linked glycerobenzoates. The diacylglycerobenzoates were fractionated into molecular species by HPLC, quantitated, and counted for radioactivity. Label was incorporated into ROS phospholipids by day 1 and was followed up through the eighth day. The dipolyenoic species 22:6-22:6 from PC showed 1 3-5 times higher radiospecific activity than the same species from either PE or PS. The rate of decline was determined by calculating the half-life of each molecular species, which was used as a measure of the turnover of the species. The percent distribution of radioactivity in the molecular species of PC and PE was quite different from the relative mass distribution at day 1. However, percent dpm approached the mole percent by 31 days. In PS, percent dpm and mole percent were the same at all time points. These results indicate that the molecular species composition of PC and PE in frog retinal ROS is determined by a combination of factors, which include rate of synthesis, rate of degradation, and selective interconversions. In contrast, PS composition appears to be determined at the time of synthesis

  14. The SCF ubiquitin ligase Slimb controls Nerfin-1 turnover in Drosophila.

    Science.gov (United States)

    Lin, Xiaohui; Wang, Feng; Li, Yuanpei; Zhai, Chaojun; Wang, Guiping; Zhang, Xiaoting; Gao, Yang; Yi, Tao; Sun, Dan; Wu, Shian

    2018-01-01

    The C2H2 type zinc-finger transcription factor Nerfin-1 expresses dominantly in Drosophila nervous system and plays an important role in early axon guidance decisions and preventing neurons dedifferentiation. Recently, increasing reports indicated that INSM1 (homologue to nerfin-1 in mammals) is a useful marker for prognosis of neuroendocrine tumors. The dynamic expression of Nerfin-1 is regulated post-transcriptionally by multiple microRNAs; however, its post-translational regulation is still unclear. Here we showed that the protein turnover of Nerfin-1 is regulated by Slimb, the substrate adaptor of SCF Slimb ubiquitin ligase complex. Mechanistically, Slimb associates with Nerfin-1 and promotes it ubiquitination and degradation in Drosophila S2R + cells. Furthermore, we determined that the C-terminal half of Nerfin-1 (Nerfin-1 CT ) is required for its binding to Slimb. Genetic epistasis assays showed that Slimb misexpression antagonizes, while knock-down enhances the activity of Nerfin-1 CT in Drosophila eyes. Our data revealed a new link to understand the underlying mechanism for Nerfin-1 turnover in post-translational level, and provided useful insights in animal development and disease treatment by manipulating the activity of Slimb and Nerfin-1. Copyright © 2017 Elsevier Inc. All rights reserved.

  15. A phase II clinical trial does not show that high dose simvastatin has beneficial effect on markers of bone turnover in multiple myeloma

    DEFF Research Database (Denmark)

    Søndergaard, Teis Esben; Pedersen, PT; Levin Andersen, Thomas

    2008-01-01

    Several studies have evaluated the impact of low dose statin (20-80 mg/day) on bone metabolism with inconclusive results despite promising data of preclinical studies. In this study, we investigated the effect of high dose simvastatin (HD-Sim) on biochemical markers of bone turnover and disease...... acid phosphatase, TRACP); (ii) bone resorption (collagen fragments CTX and NTX); (iii) bone formation (osteocalcin and aminoterminal propeptide of type I collagen PINP); (iv) cholesterol; (v) regulators of bone metabolism [osteoprotegerin (OPG) and Dickkopf-1 (DKK-1)] and (vi) disease activity...... (monoclonal proteins or free light chains in serum). TRACP activity in serum and levels of collagen fragments (NTX) in urine increased for all patients temporarily during the 7 days of treatment with HD-Sim indicating that osteoclasts may have been stimulated rather than inhibited. The other markers of bone...

  16. Turnover rate of hypoxic cells in solid tumors

    International Nuclear Information System (INIS)

    Ljungkvist, A.S.E.; Bussink, J.; Rijken, P.F.J.W.; Van Der Kogel, A.J.

    2003-01-01

    Most solid tumors contain hypoxic cells, and both the amount and duration of tumor hypoxia has been shown to influence the effect of radiation treatment negatively. It is important to understand the dynamic processes within the hypoxic cell population in non-treated tumors, and the effect of different treatment modalities on the kinetics of hypoxic cells to be able to design optimal combined modality treatments. The turnover rate of hypoxic cells was analyzed in three different solid tumor models with a double bio-reductive hypoxic marker assay with sequential injection of the two hypoxic markers. Previously it was shown that this assay could be used to detect both a decrease and an increase of tumor hypoxia in relation to the tumor vasculature with high spatial resolution. In this study the first hypoxic marker, pimonidazole, was administered at variable times relative to tumor harvest, and the second hypoxic marker, CCI-103F, was injected at a fixed time before harvest. The hypoxic cell turnover rate was calculated as the loss of pimonidazole positive cells relative to CCI-103F. The murine C38 line had the fastest hypoxic turnover rate of 60% /24h and the human xenograft line SCCNij3 had the slowest hypoxic turnover rate of 30% /24 h. The hypoxic turnover rate was most heterogeneous in the SCCNij3 line that even contained viable groups of cells that had been hypoxic for at least 5 days. The human xenograft line MEC82 fell in between with a hypoxic turnover rate of 50% /24 h. The hypoxic cell turnover was related to the potential tumor volume doubling time (Tpot) with a Tpot of 26h in C38 and 103h in SCCNij3. The dynamics of hypoxic cells, quantified with a double hypoxic marker method, showed large differences in hypoxic cell turnover rate and were related to Tpot

  17. Norepinephrine turnover in brown adipose tissue is stimulated by a single meal

    International Nuclear Information System (INIS)

    Glick, Z.; Raum, W.J.

    1986-01-01

    A single meal stimulates brown adipose tissue (BAT) thermogenesis in rats. In the present study the role of norepinephrine in this thermogenic response was assessed from the rate of its turnover in BAT after a single test meal. For comparison, norepinephrine turnover was determined in the heart and spleen. A total of 48 male Wistar rats (200 g) were trained to eat during two feeding sessions per day. On the experimental day, one group (n = 24) was meal deprived and the other (n = 24) was given a low-protein high-carbohydrate test meal for 2 h. The synthesis inhibition method with α-methyl-p-tyrosine was employed to determine norepinephrine turnover from its concentration at four hourly time points after the meal. Tissue concentrations of norepinephrine were determined by radioimmunoassay. Norepinephrine concentration and turnover rate were increased more than threefold in BAT of the meal-fed compared with the meal-deprived rats. Neither were significantly altered by the meal in the heart or spleen. The data suggest that norepinephrine mediates a portion of the thermic effect of meals that originate in BAT

  18. Treatment staff turnover in organizations implementing evidence-based practices: Turnover rates and their association with client outcomes

    Science.gov (United States)

    Garner, Bryan R.; Hunter, Brooke D.; Modisette, Kathryn C.; Ihnes, Pamela C.; Godley, Susan H.

    2011-01-01

    High staff turnover has been described as a problem for the substance use disorder treatment field. This assertion is based primarily on the assumption that staff turnover adversely impacts treatment delivery and effectiveness. This assumption, however, has not been empirically tested. In this study, we computed annualized rates of turnover for treatment staff (n=249) participating in an evidence-based practice implementation initiative and examined the association between organizational-level rates of staff turnover and client-level outcomes. Annualized rates of staff turnover were 31% for clinicians and 19% for clinical supervisors. Additionally, multilevel analyses did not reveal the expected relationship between staff turnover and poorer client-level outcomes. Rather, organizational-level rates of staff turnover were found to have a significant positive association with two measures of treatment effectiveness: less involvement in illegal activity and lower social risk. Possible explanations for these findings are discussed. PMID:22154040

  19. Kramers Turnover Theory for a Triple Well Potential

    International Nuclear Information System (INIS)

    Pollak, E.; Talkner, P.

    2001-01-01

    Kramers turnover theory is solved for a particle in a symmetric triple well potential for temperatures above the crossover temperature between tunneling and activated barrier crossing. Comparison with the turnover theory for a double well potential shows that the presence of the intermediate well always leads to a decrease of the reaction rate. At most though, the rate is a factor of two smaller than in the case of a double well potential. (author)

  20. PENGARUH KEAMANAN KERJA PADA TURNOVER INTENTION DENGAN KEPUASAN KERJA SEBAGAI VARIABEL PEMEDIASI

    Directory of Open Access Journals (Sweden)

    Utama I Wayan Mudiartha

    2015-10-01

    Full Text Available He aim of this study is to examine the effect of job security on exit intention, the effect of job security on job satisfaction, the influence of job satisfaction on turnover intention and the role of job satisfaction in mediating the relationship between job security and turnover intention. Data were collected from 56 contract administration employees at the three study programs of Faculty of Economic and Business, Udayana University and analyzed by linear regression analysis technique. The results show that job security is negatively impacts turnover intention, job security affects job satisfaction positively, job satisfaction affects turnover intention  negatively,and job satisfaction mediates the effect of job security on turnover intention.

  1. Organizational turnover as endogenous precursor of industry dynamics and organizational dissolution

    NARCIS (Netherlands)

    Cattani, Gino; Pennings, Johannes M.; Wezel, Filippo Carlo

    2002-01-01

    This paper studies the effect of organizational turnover on firm survival within the Dutch accounting service industry during the period 1880-1986. We address three issues: (1) estimating the effect of organizational turnover on organizational dissolution; (2) showing the significance of propinquity

  2. The regulation of skeletal muscle protein turnover during the progression of cancer cachexia in the Apc(Min/+ mouse.

    Directory of Open Access Journals (Sweden)

    James P White

    Full Text Available Muscle wasting that occurs with cancer cachexia is caused by an imbalance in the rates of muscle protein synthesis and degradation. The Apc(Min/+ mouse is a model of colorectal cancer that develops cachexia that is dependent on circulating IL-6. However, the IL-6 regulation of muscle protein turnover during the initiation and progression of cachexia in the Apc(Min/+ mouse is not known. Cachexia progression was studied in Apc(Min/+ mice that were either weight stable (WS or had initial (≤5%, intermediate (6-19%, or extreme (≥20% body weight loss. The initiation of cachexia reduced %MPS 19% and a further ∼50% with additional weight loss. Muscle IGF-1 mRNA expression and mTOR targets were suppressed with the progression of body weight loss, while muscle AMPK phosphorylation (Thr 172, AMPK activity, and raptor phosphorylation (Ser 792 were not increased with the initiation of weight loss, but were induced as cachexia progressed. ATP dependent protein degradation increased during the initiation and progression of cachexia. However, ATP independent protein degradation was not increased until cachexia had progressed beyond the initial phase. IL-6 receptor antibody administration prevented body weight loss and suppressed muscle protein degradation, without any effect on muscle %MPS or IGF-1 associated signaling. In summary, the %MPS reduction during the initiation of cachexia is associated with IGF-1/mTOR signaling repression, while muscle AMPK activation and activation of ATP independent protein degradation occur later in the progression of cachexia. IL-6 receptor antibody treatment blocked cachexia progression through the suppression of muscle protein degradation, while not rescuing the suppression of muscle protein synthesis. Attenuation of IL-6 signaling was effective in blocking the progression of cachexia, but not sufficient to reverse the process.

  3. The Regulation of Skeletal Muscle Protein Turnover during the Progression of Cancer Cachexia in the ApcMin/+ Mouse

    Science.gov (United States)

    White, James P.; Baynes, John W.; Welle, Stephen L.; Kostek, Matthew C.; Matesic, Lydia E.; Sato, Shuichi; Carson, James A.

    2011-01-01

    Muscle wasting that occurs with cancer cachexia is caused by an imbalance in the rates of muscle protein synthesis and degradation. The ApcMin/+ mouse is a model of colorectal cancer that develops cachexia that is dependent on circulating IL-6. However, the IL-6 regulation of muscle protein turnover during the initiation and progression of cachexia in the ApcMin/+ mouse is not known. Cachexia progression was studied in ApcMin/+ mice that were either weight stable (WS) or had initial (≤5%), intermediate (6–19%), or extreme (≥20%) body weight loss. The initiation of cachexia reduced %MPS 19% and a further ∼50% with additional weight loss. Muscle IGF-1 mRNA expression and mTOR targets were suppressed with the progression of body weight loss, while muscle AMPK phosphorylation (Thr 172), AMPK activity, and raptor phosphorylation (Ser 792) were not increased with the initiation of weight loss, but were induced as cachexia progressed. ATP dependent protein degradation increased during the initiation and progression of cachexia. However, ATP independent protein degradation was not increased until cachexia had progressed beyond the initial phase. IL-6 receptor antibody administration prevented body weight loss and suppressed muscle protein degradation, without any effect on muscle %MPS or IGF-1 associated signaling. In summary, the %MPS reduction during the initiation of cachexia is associated with IGF-1/mTOR signaling repression, while muscle AMPK activation and activation of ATP independent protein degradation occur later in the progression of cachexia. IL-6 receptor antibody treatment blocked cachexia progression through the suppression of muscle protein degradation, while not rescuing the suppression of muscle protein synthesis. Attenuation of IL-6 signaling was effective in blocking the progression of cachexia, but not sufficient to reverse the process. PMID:21949739

  4. [Turnover Experience of Male Nurses].

    Science.gov (United States)

    Kim, Hyunsu; Lee, Jeongseop

    2017-02-01

    The aim of this study was to identify turnover experiences of men in nursing and to derive a substantive theory on the turnover experience of men who are nurses. Data were collected through in-depth interviews with 13 men who had worked as a nurse for 1 year or more, and had a turnover experience during that period. Collected data were analyzed on the basis of Strauss and Corbin's grounded theory. The core category in the turnover experiences of the respondents was 'seeking a stable place for me'. In the analysis of the core category, types of 'contentment', 'seeking', 'survival' and 'confusion' were identified. The sequential stages of these nurses' turnover experience were 'confrontation', 'incertitude', 'retrying' and 'realization'. However, when a problem arose in the process, they returned to the stage of confusion. Thus, these stages could occur in a circular fashion. These findings provide a deep understanding of the turnover experience of men in nursing and offers new information about how they adapt to nursing practice. The findings should be useful as foundational data for men who hope to become nurses and also for managers responsible for nurses who are men. © 2017 Korean Society of Nursing Science

  5. Occupational stress and employee turnover.

    Science.gov (United States)

    Bridger, Robert S; Day, Andrea J; Morton, Kate

    2013-01-01

    Questionnaire data captured in January-March 2007 were examined in relation to turnover in males and females during the next five years. In general, most of the workplace stressors (such as role conflict or peer support) were not antecedents of turnover in any group. Junior personnel with psychological strain in 2007 had an increased risk of turnover in the next five years. Low commitment to the service in 2007 increased the odds of turnover in male and female juniors and in female officers. Female juniors with less effective skills for coping with stress and who exercised less frequently on a weekly basis were more likely to leave. An incidental finding was that the odds of turnover were three times greater in female officers with children than in female officers with no children. Stress management interventions focusing on effective coping and sports and exercise participation which are targeted appropriately may improve retention.

  6. Managing voluntary turnover through challenging assignments

    NARCIS (Netherlands)

    Preenen, P.T.Y.; de Pater, I.E.; van Vianen, A.E.M.; Keijzer, L.

    2011-01-01

    This study examines employees’ challenging assignments as manageable means to reduce turnover intentions, job search behaviors, and voluntary turnover. Results indicate that challenging assignments are negatively related to turnover intentions and job search behaviors and that these relationships

  7. Managing voluntary turnover through challenging assignments

    NARCIS (Netherlands)

    Preenen, P.T.Y.; Pater, I.E. de; Vianen, A.E.M. van; Keijzer, L.

    2011-01-01

    This study examines employees' challenging assignments as manageable means to reduce turnover intentions, job search behaviors, and voluntary turnover. Results indicate that challenging assignments are negatively related to turnover intentions and job search behaviors and that these relationships

  8. Changes in alanine turnover rate due to nutritional and genetic obesity in the rat.

    Science.gov (United States)

    Yebras, M; Salvadó, J; Arola, L; Remesar, X; Segués, T

    1994-08-01

    The changes in alanine turnover were determined in Zucker rats, which were either genetically obese (fa/fa) or rendered obese by dietary treatment (cafeteria fed). The whole body rate of alanine turnover was higher in genetically obese rats than in rats in which obesity was induced by diet (cafeteria). This is possibly due to variations in the rate of the amino acid incorporation into proteins, since the rate of whole body alanine degradation is the same for both groups. Thus, the different pattern followed by alanine turnover rate in these types of obese animals reflects the differences in the nitrogen economy of these animals, pointing to a higher alanine utilization in the genetically obese animals and a conservative management of alanine in the cafeteria-fed animals.

  9. ANTESEDEN EMPLOYEE TURNOVER

    Directory of Open Access Journals (Sweden)

    Heryadi Fardilah

    2018-03-01

    Full Text Available This research is concerning the effect of workplace environment, job satisfaction, and  job performance on employee turnover, and the background is to get the convenience of employees condition, the satisfaction of job results, maximum performance, and keep and reduce in and out employees. The purpose of this research is to see how far the influence of workplace environment, job satisfaction, and job performance on employee turnover. Planning of this research uses primary data that is got by handing over questioners to 200 employees in Telecommunication company in East Jakarta. The analysis method which is used is double regresi.  Results of  this  research give conclusion that there's a positive and significant influence of workplace environment, job satisfaction, and job performance on employee turnover.

  10. Bone turnover in postmenopausal osteoporosis. Effect of calcitonin treatment.

    Science.gov (United States)

    Civitelli, R; Gonnelli, S; Zacchei, F; Bigazzi, S; Vattimo, A; Avioli, L V; Gennari, C

    1988-10-01

    To investigate the effectiveness of calcitonin treatment of postmenopausal osteoporosis in relation to bone turnover, we examined 53 postmenopausal osteoporotic women before and after one year of therapy with salmon calcitonin (sCT), at the dose of 50 IU every other day. Baseline evaluation revealed that 17 (32%) patients had high turnover (HTOP), and 36 (68%) normal turnover osteoporosis (NTOP) as assessed by measurement of whole body retention (WBR) of 99mTc-methylene diphosphonate. The two groups did not differ in terms of bone mineral content (BMC) measured by dual photon absorptiometry at both lumbar spine and femoral diaphysis. However, HTOP patients had higher levels of serum osteocalcin (OC) and urinary hydroxyproline excretion (HOP/Cr). Multivariate regression analysis showed no correlation between parameters of bone turnover (WBR, OC, HOP/Cr) and both femoral and vertebral bone density; the latter being negatively correlated only with the years elapsed since menopause (R2 = 0.406). Treatment with sCT resulted in a significant increase of vertebral BMC in the 53 patients taken as a whole group (+/- 7%, P less than 0.001). When the results obtained in HTOP and NTOP were analyzed separately, only those with HTOP showed a marked increment of spinal BMC (+22%, P less than 0.001), NTOP subjects neither gained nor lost bone mineral during the study. Femoral BMC decreased in the whole group after sCT therapy (-3%, P less than 0.003). However, HTOP patients maintained initial BMC values, whereas those with NTOP lost a significant amount of bone during the study period (-5%, P less than 0.001). The increase of vertebral bone mass was associated with a marked depression of bone turnover detectable in both subsets of patients and in the whole group. (a) assessment of bone turnover cannot help predict the severity of bone loss in postmenopausal osteoporosis; (b) calcitonin therapy appears to be particularly indicated for patients with high-turnover osteoporosis

  11. Costs of employee turnover

    Directory of Open Access Journals (Sweden)

    Jiří Duda

    2013-01-01

    Full Text Available The aim of this paper is to establish a general methodology for calculating the costs incurred by employee turnover. This paper deals with identification of costs incurred by the departure of an employee, and does not deal with the cost of recruitment of a new employee. Economic calculations are adjusted to the tax policy in the Czech Republic. The costs of employee turnover (according to Bliss, 2012 include the costs of substitution of the unoccupied position, costs of conducting the exit interview and termination of the contract. The cost of an executive’s time to understand the causes of leaving and costs of the leaving employee’s training were also determined. Important factors in the costs of employee turnover also include the loss of knowledge and possibly also a loss of customers. Costs of lost employee and department productiveness represent an important part of the costs of employee turnover, as well. For all of these costs there have been proposed general calculations formulas.

  12. [New nurse turnover intention and influencing factors].

    Science.gov (United States)

    Han, Sang Sook; Sohn, In Soon; Kim, Nam Eun

    2009-12-01

    The study was done to identify turnover intention in new nurses according to characteristics of the nurses and other factors affecting turnover and to provide data to set up a strategy to reduce the turnover. Data were collected from 1,077 new nurses who had less than 12 months employment experience and worked in one of 188 hospitals. Eight research instruments were used. Data analysis was done using SPSS WIN 15.0 program. Several factors influence new nurse turnover intention. The average score for turnover intention was 2.12. The scores for subscales were self efficacy, 3.76, nursing performance, 3.90, job satisfaction, 2.09, organization commitment, 1.28, stress, 1.32, burnout, 2.82 and nursing organizational culture, 3.29. Turnover intention was related to self efficacy, nursing performance, job satisfaction, organization commitment, stress, burnout, nursing organizational culture, duration of in-class training, duration of on the job training, number of hospital beds, length of employment and duration of employment in current workplace. The predicting factors for turnover intention were burnout, stress, duration of employment in the current workplace, self efficacy and nursing performance. Those factors explained 51.6% of turnover intention. New nurse turnover intention can be reduced by mitigating the factors affecting this intention.

  13. Turnover among Community Mental Health Workers in Ohio.

    Science.gov (United States)

    Bukach, Ashley M; Ejaz, Farida K; Dawson, Nicole; Gitter, Robert J

    2017-01-01

    This study examined turnover of community mental health workers in 42 randomly selected mental health agencies in Ohio. The turnover rate in 2011 was 26 %. A regression analysis indicated that agencies with lower turnover offered higher maximum pay and were smaller in size, while those offering career advancement opportunities, such as career ladder programs, had higher turnover. The findings suggest that improving wages for workers is likely to reduce turnover. It is also possible that smaller agencies have lower turnover due to stronger relationships with workers and/or more successful hiring practices. Furthermore, turnover that occurs as a result of career advancement could have positive effects and should be examined separate from other types of turnover in the future.

  14. Histone turnover within nonproliferating cells

    International Nuclear Information System (INIS)

    Commerford, S.L.; Carsten, A.L.; Cronkite, E.P.

    1982-01-01

    The turnover of DNA and histones in the livers and brains of mice has been determined. These mice had been exposed to constant levels of tritiated water from conception until they were 8 months old. At this point, exposure to tritium was discontinued, and the tritium remaining in DNA and histones was measured at various intervals afterward. The half-lives calculated for these components (with 95% confidence limits given in parentheses) were 117 (85 to 188) days for liver histone, 318 (241 to 466) days for liver DNA, 159 (129 to 208) days for brain histone and 593 (376 to 1406) days for brain DNA. The difference between histone and DNA turnover is statistically significant for both tissues and indicates that histone turnover within tissues cannot be solely accounted for by cell turnover within the tissue but also must include histone turnover within living cells. The half-life of histone within cells is estimated to be 117 (88 to 178) days in liver and 223 (187 to 277) days in brain

  15. Using Turnover as a Recruitment Strategy

    Science.gov (United States)

    Duncan, Sandra

    2009-01-01

    Teacher turnover is notoriously high in the field of early childhood education with an estimated 33% of staff exiting the workplace each year. Turnover is costly. Not only do high levels of turnover negatively impact children's growth and development, it also erodes the program's economic stability and wherewithal to provide effective operations…

  16. Constitutive endocytosis and turnover of the neuronal glycine transporter GlyT2 is dependent on ubiquitination of a C-terminal lysine cluster.

    Directory of Open Access Journals (Sweden)

    Jaime de Juan-Sanz

    Full Text Available Inhibitory glycinergic neurotransmission is terminated by sodium and chloride-dependent plasma membrane glycine transporters (GlyTs. The mainly glial glycine transporter GlyT1 is primarily responsible for the completion of inhibitory neurotransmission and the neuronal glycine transporter GlyT2 mediates the reuptake of the neurotransmitter that is used to refill synaptic vesicles in the terminal, a fundamental role in the physiology and pathology of glycinergic neurotransmission. Indeed, inhibitory glycinergic neurotransmission is modulated by the exocytosis and endocytosis of GlyT2. We previously reported that constitutive and Protein Kinase C (PKC-regulated endocytosis of GlyT2 is mediated by clathrin and that PKC accelerates GlyT2 endocytosis by increasing its ubiquitination. However, the role of ubiquitination in the constitutive endocytosis and turnover of this protein remains unexplored. Here, we show that ubiquitination of a C-terminus four lysine cluster of GlyT2 is required for constitutive endocytosis, sorting into the slow recycling pathway and turnover of the transporter. Ubiquitination negatively modulates the turnover of GlyT2, such that increased ubiquitination driven by PKC activation accelerates transporter degradation rate shortening its half-life while decreased ubiquitination increases transporter stability. Finally, ubiquitination of GlyT2 in neurons is highly responsive to the free pool of ubiquitin, suggesting that the deubiquitinating enzyme (DUB ubiquitin C-terminal hydrolase-L1 (UCHL1, as the major regulator of neuronal ubiquitin homeostasis, indirectly modulates the turnover of GlyT2. Our results contribute to the elucidation of the mechanisms underlying the dynamic trafficking of this important neuronal protein which has pathological relevance since mutations in the GlyT2 gene (SLC6A5 are the second most common cause of human hyperekplexia.

  17. Beyond the tradition: test of an integrative conceptual model on nurse turnover.

    Science.gov (United States)

    Battistelli, A; Portoghese, I; Galletta, M; Pohl, S

    2013-03-01

    This paper aimed to extend research on nurse turnover by developing and testing a theoretical model of turnover intention that includes two emergent key off-the-job constructs, work-family conflict (WFC) and community embeddedness (CE). Nurse turnover is considered one of the most significant issues in health care. There is a considerable body of knowledge that has focused on the study of the on-the-job factors of nurse turnover, showing the important role of job attitudes. Recently, WFC and job embeddedness (JE) have been identified as variables that could help explain levels of nurse turnover. Using structural equation modelling from a cross-sectional survey, the relationships between the variables were explored in a sample of 440 nurses from an Italian public hospital. The questionnaire measures demographic data and psychosocial factors such as job satisfaction, organizational commitment, WFC, CE and turnover intentions. The findings supported the importance of non-work dimensions in turnover models. The results suggest that when studying turnover phenomena in health organizations, the extra-work domains (WFC and JE) can contribute to a decrease in the intention to leave, in addition to the more typically emphasized attitude dimension. © 2012 The Authors. International Nursing Review © 2012 International Council of Nurses.

  18. Supervisory Turnover in Outpatient Substance Abuse Treatment

    Science.gov (United States)

    Knight, Danica K.; Broome, Kirk M.; Edwards, Jennifer R.; Flynn, Patrick M.

    2009-01-01

    Staff turnover is a significant issue within substance abuse treatment, with implications for service delivery and organizational health. This study examined factors associated with turnover among supervisors in outpatient substance abuse treatment. Turnover was conceptualized as being an individual response to organizational-level influences, and predictors represent aggregate program measures. Participants included 532 staff (including 467 counselors and 65 clinical/program directors) from 90 programs in four regions of the USA. Using logistic regression, analyses of structural factors indicated that programs affiliated with a parent organization and those providing more counseling hours to clients had higher turnover rates. When measures of job attitudes were included, only parent affiliation and collective appraisal of satisfaction were related to turnover. Subsequent analyses identified a trend toward increased supervisory turnover when satisfaction was low following the departure of a previous supervisor. These findings suggest that organizational-level factors can be influential in supervisory turnover. PMID:19949883

  19. How Teacher Turnover Harms Student Achievement

    Science.gov (United States)

    Ronfeldt, Matthew; Loeb, Susanna; Wyckoff, James

    2013-01-01

    Researchers and policymakers often assume that teacher turnover harms student achievement, though recent studies suggest this may not be the case. Using a unique identification strategy that employs school-by-grade level turnover and two classes of fixed-effects models, this study estimates the effects of teacher turnover on over 850,000 New York…

  20. Differential Subplastidial Localization and Turnover of Enzymes Involved in Isoprenoid Biosynthesis in Chloroplasts.

    Directory of Open Access Journals (Sweden)

    Catalina Perello

    Full Text Available Plastidial isoprenoids are a diverse group of metabolites with roles in photosynthesis, growth regulation, and interaction with the environment. The methylerythritol 4-phosphate (MEP pathway produces the metabolic precursors of all types of plastidial isoprenoids. Proteomics studies in Arabidopsis thaliana have shown that all the enzymes of the MEP pathway are localized in the plastid stroma. However, immunoblot analysis of chloroplast subfractions showed that the first two enzymes of the pathway, deoxyxylulose 5-phosphate synthase (DXS and reductoisomerase (DXR, can also be found in non-stromal fractions. Both transient and stable expression of GFP-tagged DXS and DXR proteins confirmed the presence of the fusion proteins in distinct subplastidial compartments. In particular, DXR-GFP was found to accumulate in relatively large vesicles that could eventually be released from chloroplasts, presumably to be degraded by an autophagy-independent process. Together, we propose that protein-specific mechanisms control the localization and turnover of the first two enzymes of the MEP pathway in Arabidopsis chloroplasts.

  1. The validation of the turnover intention scale

    Directory of Open Access Journals (Sweden)

    Chris F.C. Bothma

    2013-04-01

    Full Text Available Orientation: Turnover intention as a construct has attracted increased research attention in the recent past, but there are seemingly not many valid and reliable scales around to measure turnover intention. Research purpose: This study focused on the validation of a shortened, six-item version of the turnover intention scale (TIS-6. Motivation for the study: The research question of whether the TIS-6 is a reliable and a valid scale for measuring turnover intention and for predicting actual turnover was addressed in this study. Research design, approach and method: The study was based on a census-based sample (n= 2429 of employees in an information, communication and technology (ICT sector company (N= 23 134 where the TIS-6 was used as one of the criterion variables. The leavers (those who left the company in this sample were compared with the stayers (those who remained in the employ of the company in this sample in respect of different variables used in the study. Main findings: It was established that the TIS-6 could measure turnover intentions reliably (α= 0.80. The TIS-6 could significantly distinguish between leavers and stayers (actual turnover, thereby confirming its criterion-predictive validity. The scale also established statistically significant differences between leavers and stayers in respect of a number of the remaining theoretical variables used in the study, thereby also confirming its differential validity. These comparisons were conducted for both the 4-month and the 4-year period after the survey was conducted. Practical/managerial implications: Turnover intention is related to a number of variables in the study which necessitates a reappraisal and a reconceptualisation of existing turnover intention models. Contribution/value-add: The TIS-6 can be used as a reliable and valid scale to assess turnover intentions and can therefore be used in research to validly and reliably assess turnover intentions or to

  2. A role for PERK in the mechanism underlying fluoride-induced bone turnover

    International Nuclear Information System (INIS)

    Sun, Fei; Li, Xining; Yang, Chen; Lv, Peng; Li, Guangsheng; Xu, Hui

    2014-01-01

    While it has been well-documented that excessive fluoride exposure caused the skeletal disease and osteoblasts played a critical role in the advanced skeletal fluorosis, the underlying mechanism that mediated these effects remain poorly understood. The present study was undertaken to examine the effect of fluoride on bone of rats and MC3T3-E1 cells in vitro. Herein we found pathological features of high bone turnover in fluoride-treated rats, which was supported by an increase of osteogenic and osteoclastogenic genes expression in different stages of fluoride exposure. The skeletal toxicity of fluoride was accompanied by activation of endoplasmic reticulum (ER) stress and subsequent unfolded protein response (UPR). A novel finding of this study was that expression of PKR-like endoplasmic reticulum kinase (PERK) was the same trend with receptor activator for nuclear factor-κ B ligand (RANKL), and NF-E2 p45-related factor 2 (Nrf2) was the same trend with Runt-related transcription factor 2 (Runx2) in bones of rats exposed to varied fluoride condition. Based on these data, we hypothesized that up-regulation of PERK probably played a role in mediating bone turnover induced by fluoride. Action of fluoride on MC3T3-E1 cells differentiation was demonstrated through analysis of alkaline phosphatase (ALP) activity and mineralized nodules formation. Meantime, an increase of binding immunoglobulin protein (BiP) expression indicated the active ER stress in cells exposed to various dose of fluoride. Blocking PERK expression using siRNA showed the obvious decrease of osteogenic and osteoclastogenic factors expression in MC3T3-E1 cells exposed to certain dose of fluoride that could positively stimulate osteoblastic viability. In conclusion these findings underscore the importance of PERK in modulating fluoride induced bone formation and bone resorption. Understanding the link between PERK and bone turnover could probe into the mechanism underlying different bone lesion of

  3. How Serious of a Problem is Staff Turnover in Substance Abuse Treatment? A Longitudinal Study of Actual Turnover1

    Science.gov (United States)

    Eby, Lillian T.; Burk, Hannah; Maher, Charleen P.

    2010-01-01

    In the substance abuse treatment field, the annual turnover rate is cited as being anywhere between 19 and 50 percent (Johnson & Roman, 2002; Gallon, Gabriel, & Knudsen, 2003; Knudsen et al., 2003; McLellan et al., 2003). However, no research to date has evaluated these claims by tracking turnover longitudinally using organizational turnover data from substance abuse treatment centers. This research presents the results of a longitudinal study designed to systematically examine actual turnover among counselors and clinical supervisors. Twenty-seven geographically dispersed treatment organizations, serving a wide range of clients in the public and private sector, provided data for the study over a two year time span (2008–2009). The annual turnover rate was 33.2% for counselors and 23.4% for clinical supervisors. For both groups the majority of turnover was voluntary (employee-initiated). Specific reasons for turnover were largely consistent across the two groups, with the most common reason being a new job or new opportunity. The findings are discussed in terms of the unique employment context of substance abuse treatment. Practical recommendations are also discussed to help stem the tide of turnover in the field of substance abuse treatment. PMID:20675097

  4. How serious of a problem is staff turnover in substance abuse treatment? A longitudinal study of actual turnover.

    Science.gov (United States)

    Eby, Lillian T; Burk, Hannah; Maher, Charleen P

    2010-10-01

    In the substance abuse treatment field, the annual turnover rate is cited as being anywhere between 19% and 50% (J.A. Johnson & P.M. Roman, 2002; S.L. Gallon, R.M. Gabriel, J.R.W. Knudsen, 2003; H.K. Knudsen, J.A. Johnson, & P.M. Roman, 2003; A.T. McLellan, D. Carise, & H.D. Kleber, 2003). However, no research to date has evaluated these claims by tracking turnover longitudinally using organizational turnover data from substance abuse treatment centers. This research presents the results of a longitudinal study designed to systematically examine actual turnover among counselors and clinical supervisors. Twenty-seven geographically dispersed treatment organizations, serving a wide range of clients in the public and private sector, provided data for the study over a 2-year time span (2008-2009). The annual turnover rate was 33.2% for counselors and 23.4% for clinical supervisors. For both groups, the majority of turnover was voluntary (employee-initiated). Specific reasons for turnover were largely consistent across the two groups, with the most common reason being a new job or new opportunity. The findings are discussed in terms of the unique employment context of substance abuse treatment. Practical recommendations are also discussed to help stem the tide of turnover in the field of substance abuse treatment. Copyright (c) 2010 Elsevier Inc. All rights reserved.

  5. Positive muscle protein net balance and differential regulation of atrogene expression after resistance exercise and milk protein supplementation

    DEFF Research Database (Denmark)

    Reitelseder, Søren; Agergaard, Jakob; Doessing, Simon

    2014-01-01

    Purpose Resistance exercise and amino acid availability are positive regulators of muscle protein net balance (NB). However, anabolic responses to resistance exercise and protein supplementation deserve further elucidation. The purpose was to compare intakes of whey, caseinate (both: 0.30 g/kg lean...... body mass), or a non-caloric control after heavy resistance exercise on protein turnover and mRNA expressions of forkhead homeobox type O (FOXO) isoforms, muscle RING finger 1 (MuRF1), and Atrogin1 in young healthy males. Methods Protein turnover was determined by stable isotope-labeled leucine...

  6. Chronic Teacher Turnover in Urban Elementary Schools

    Directory of Open Access Journals (Sweden)

    Kacey Guin

    2004-08-01

    Full Text Available This study examines the characteristics of elementary schools that experience chronic teacher turnover and the impacts of turnover on a school’s working climate and ability to effectively function. Based on evidence from staff climate surveys and case studies, it is clear that high turnover schools face significant organizational challenges. Schools with high teacher turnover rates have difficulty planning and implementing a coherent curriculum and sustaining positive working relationships among teachers. The reality of these organizational challenges is particularly alarming, given that high turnover schools are more likely to serve low-income and minority students. The negative relationship between teacher turnover and school functioning, and the fact that turbulent schools are disproportionately likely to serve lowincome and minority students have important implications for both district and school-level policies. Specifically: Teacher turnover rates are one indicator of school health, which school districts should consider when focusing on school improvements. Districts need to begin by developing the means to identify individual schools that experience high levels of teacher turnover. Current district policies in implementing professional development for teachers in low-performing schools are inefficient when teachers do not remain in the schools in which they are trained. In order for low-performing schools to improve, districts need to consider providing incentive programs so that high quality teachers apply for, and remain in, these schools. Future research is needed to address the causal link between turnover, organizational functioning and student outcomes. Additionally, there is a need for research examining district policies that may facilitate teacher turnover within a district, including how districts place and transfer teachers, as well as how teachers’ salaries are budgeted.

  7. How Employee Turnover Affects Productivity

    DEFF Research Database (Denmark)

    Eriksen, Bo

    Research on employee turnover suggests that turnover results in negative organization-level outcomes. This paper provides a firm-level analysis of the impact of the in- and outflows of human resources on productivity and how the presence of organizational slack resources moderates the effects...... moderate this effect so that the negative consequences of employee turnover are less severe for larger, older and capital intensive firms. These moderating variables indicate the presence of slack resources in the firm, and thus that the accumulation of slack reduces the efficiency losses from employee...

  8. Glucosamine but not ibuprofen alters cartilage turnover in osteoarthritis patients in response to physical training

    DEFF Research Database (Denmark)

    Petersen, Susanne Germann; Saxne, T; Heinegard, D

    2010-01-01

    OBJECTIVE: To investigate changes in levels of serum cartilage oligomeric matrix protein (COMP) and urine c-telopeptide of type-2 collagen (CTX-II) as markers for cartilage turnover in patients with osteoarthritis (OA) of the knee, in response to muscle strength training in combination with treat......OBJECTIVE: To investigate changes in levels of serum cartilage oligomeric matrix protein (COMP) and urine c-telopeptide of type-2 collagen (CTX-II) as markers for cartilage turnover in patients with osteoarthritis (OA) of the knee, in response to muscle strength training in combination......). RESULTS: All three groups increased their muscle strength following 12 weeks of strength training (Preduced in the glucosamine-treated group after the training period (P=0.012), whereas they did not change in the two other groups. Glucosamine reduced COMP statistically...

  9. Buckwheat seedling flavonoids do not undergo rapid turnover

    International Nuclear Information System (INIS)

    Margna, U.; Vainjaerv, T.

    1981-01-01

    Pulse-labelling with exogenous [1- 14 C]-L-phenylalanine showed that of all flavonoids of buckwheat seedling cotyledons only anthocyanins underwent a slow turnover (not more than 6-8 per cent a day) whilst the major flavonoids, rutin and four C-glycosylflavones, remained metabolically stable within at least 7 days. From excised hypocotyls pulse-labelled flavonoids (anthocyanins and rutin) began to disappear gradually beginning with the second day of incubation. As hypocotyls, however, during prolonged incubation soon began to autolyse a considerable part of that loss was obviously due to abnormal shifts in cell metabolic activities with a possibility that some microbial process was also involved. In hypocotyls of intact seedlings pulse-labelled rutin, similar to rutin in cotyledons, showed no signs of turnover. (author)

  10. On the controlling mechanism of the upper turnover states in the NTC regime

    KAUST Repository

    Ji, Weiqi

    2015-12-18

    Using n-butane, n-heptane and iso-octane as representative fuels exhibiting NTC (negative temperature coefficient) behavior, comprehensive computational studies with detailed mechanisms and theoretical analysis were performed to investigate the upper stationary point, denoted as turnover states, on the NTC curve near the higher temperature regime, where the ignition delay τ exhibits a local maximum. It is found that the global behavior of the turnover states exhibits distinctive thermodynamic and kinetic characteristics under different pressures, in that the ignition delay at the turnover states shows an Arrhenius dependence on the temperature T and an approximate inverse quadratic power law dependence on the pressure P. These global behaviors imply that the temperature and pressure of the turnover states are not independent and can be correlated by Arrhenius dependence, as ln P ∝ 1/T. Further theoretical analyses demonstrate that such turnover states result from the competition between the low-temperature chain branching reactions and the decomposition of the intermediate species, and therefore correspond to a critical value, α, of the ratio of OH production from low-temperature chemistry. In addition, the ignition delay at the turnover state can be well correlated by the analytical expression derived by Peters et al., with the further demonstration that the pressure dependence of the turnover ignition delay mainly result from the H2O2 decomposition reaction. Comparison of the present results with the literature experimental data of n-heptane ignition delay time shows very good agreement.

  11. Job Satisfaction and Employee Turnover Intention: A Case Study of Private Hospital in Erbil

    Directory of Open Access Journals (Sweden)

    Govand Anwar

    2015-09-01

    Full Text Available Today it became a huge challenge for Human Resource Managers to retain the employees for longer time of period and decrease the rate of employee turnover. The main research objective is to find out the correlation between job satisfaction and employee turnover intention in private hospital in Erbil. A quantitative method was used to analyze the current study. 144 participants were involved in this study from private hospital in Erbil. The correlation between job satisfaction factor as independent factor and turnover as dependent factor, the value of R for the Job satisfaction is =.386** which indicates that turnover is a positive and weak correlation with turnover intention. The coefficients analysis for this study, the value Beta for turnover is = .386> 0.01, which supported the research hypothesis. This study showed that the there is a positive correlation between job satisfaction and employee turnover. Finally, on the turnover intentions of private hospital personnel in Erbil, most of them would quit in case if they have a better opportunities.

  12. Differential challenge stressor-hindrance stressor relationships with job attitudes, turnover intentions, turnover, and withdrawal behavior: a meta-analysis.

    Science.gov (United States)

    Podsakoff, Nathan P; LePine, Jeffery A; LePine, Marcie A

    2007-03-01

    In this article, a 2-dimensional work stressor framework is used to explain inconsistencies in past research with respect to stressor relationships with retention-related criteria. Results of meta-analyses of 183 independent samples indicated that whereas hindrance stressors had dysfunctional relationships with these criteria (negative relationships with job satisfaction and organizational commitment and positive relationships with turnover intentions, turnover, and withdrawal behavior), relationships with challenge stressors were generally the opposite (positive relationships with job satisfaction and organizational commitment and negative relationships with turnover intentions and turnover). Results also suggested that the differential relationships between challenge stressors and hindrance stressors and the more distal criteria (withdrawal behavior and turnover) were due, in part, to the mediating effects of job attitudes. (c) 2007 APA, all rights reserved.

  13. Lactate turnover in fast-moving vertebrates: The control of plasma metabolite fluxes

    Energy Technology Data Exchange (ETDEWEB)

    Weber, J.M.

    1987-01-01

    The goals of this thesis were: (1) to investigate the major factors involved in the regulation of plasma metabolite turnover at the whole-organism level-using lactate as a model, and (2) to determine whether endurance-adapted animals can support higher lactate turnover rates than sedentary animals. Lactate turnover was measured by bolus injection of (U{sup {minus}14}C)lacetate in skipjack tuna, Katsuwonus pelamis, and in thoroughbred race horses, Equus caballus. In tuna, turnover rates ranged from 112 to 431 umol min{sup {minus}1} kg{sup {minus}1}, and they were positively correlated with (lactate). These rates were higher than expected for a mammal of equivalent size. Plots of resting lactate and glucose turnover rates vs body mass on a log-log scale were linear for a wide range mammalian body sizes, and they showed the same slope as the classic body mass vs metabolic rate relationship.

  14. Protein synthesis and antioxidant capacity in aging mice : Effects of long-term voluntary exercise

    NARCIS (Netherlands)

    Vaanholt, Lobke M.; Speakman, John R.; Garland, Theodore; Lobley, Gerald E.; Visser, G. Henk

    2008-01-01

    Exercise increases metabolic rate and the production of reactive oxygen species (ROS) but also elevates protein turnover. ROS cause damage to macromolecules (e. g., proteins) and thereby contribute to aging. Protein turnover removes and replaces damaged proteins. The balance between these two

  15. Addressing employee turnover and retention: keeping your valued performers.

    Science.gov (United States)

    McConnell, Charles R

    2011-01-01

    Employee turnover and employee retention are inextricably linked; to control turnover is to enhance retention. Turnover is a relatively simple concept; however, considerable confusion often results when addressing turnover because of differences in how it is defined; that is, what is counted, how it is counted, and how the turnover rates are expressed. Turnover is also costly, although not enough attention is paid to its cost because so much of it is indirect and thus not readily visible. There are a variety of causes of turnover, some that can be corrected and some that cannot be avoided. Reducing or otherwise controlling turnover requires continuing management attention to its causes and constant recognition of what can and should be controlled and what cannot be controlled. Ongoing attention to turnover is an essential part of the department manager's role; every improvement in turnover is a direct improvement in retention, with eventual positive effects on the bottom line.

  16. Turnover of regulated nurses in long-term care facilities.

    Science.gov (United States)

    Chu, Charlene H; Wodchis, Walter P; McGilton, Katherine S

    2014-07-01

    To describe the relationship between nursing staff turnover in long-term care (LTC) homes and organisational factors consisting of leadership practices and behaviours, supervisory support, burnout, job satisfaction and work environment satisfaction. The turnover of regulated nursing staff [Registered Nurses (RNs) and Registered Practical Nurses (RPNs)] in LTC facilities is a pervasive problem, but there is a scarcity of research examining this issue in Canada. The study was conceptualized using a Stress Process model. Distinct surveys were distributed to administrators to measure organisational factors and to regulated nurses to measure personal and job-related sources of stress and workplace support. In total, 324 surveys were used in the linear regression analysis to examine factors associated with high turnover rates. Higher leadership practice scores were associated with lower nursing turnover; a one score increase in leadership correlated with a 49% decrease in nursing turnover. A significant inverse relationship between leadership turnover and nurse turnover was found: the higher the administrator turnover the lower the nurse turnover rate. Leadership practices and administrator turnover are significant in influencing regulated nurse turnover in LTC. Long-term care facilities may want to focus on building good leadership and communication as an upstream method to minimize nurse turnover. © 2013 John Wiley & Sons Ltd.

  17. Stayers, Leavers, and Switchers Among Certified Nursing Assistants in Nursing Homes: A Longitudinal Investigation of Turnover Intent, Staff Retention, and Turnover

    Science.gov (United States)

    Rosen, Jules

    2011-01-01

    Purpose: Studies of certified nursing assistant (CNA) turnover in nursing homes are typically cross-sectional and include full-time and part-time workers. We conducted a longitudinal study to evaluate the job factors and work attitudes associated with just full-time staying or leaving. For those who did not stay, we assessed reasons for leaving and satisfaction following job transition. Design and Methods: A random sample of CNAs identified through the Pennsylvania Department of Health's CNA registry, working≥30 hr weekly in a nursing facility was surveyed by telephone at baseline and 1 year later. Results: Of the 620 responding to both surveys, 532 (85.8%) remained (stayers), 52 (8.4%) switched to another facility (switchers), and 36 (5.8%) left the industry (leavers). At baseline, switchers reported higher turnover intentions and fewer benefits compared with stayers and left for new opportunities. Leavers had lower job satisfaction and emotional well-being and left for health reasons. Turnover intentions were predicted by low job satisfaction and low emotional well-being. Actual turnover was predicted only by turnover intentions and by the absence of health insurance. Pay was not a predictor of turnover intent or turnover. Implications: There are two distinct groups of CNAs contributing to turnover. Attitudinal factors, such as job satisfaction and emotional well-being, are mediated via turnover intentions to effect actual turnover. Even accounting for methodological differences, this turnover rate is lower than previous studies, which use alternative methods and include part-time workers. This study should help nursing home administrators better understand the work-related factors associated with staff turnover. PMID:21498629

  18. Salary, Performance, and Superintendent Turnover

    Science.gov (United States)

    Grissom, Jason A.; Mitani, Hajime

    2016-01-01

    Purpose: Superintendent retention is an important goal for many school districts, yet the factors contributing to superintendent turnover are poorly understood. Most prior quantitative studies of superintendent turnover have relied on small, cross-sectional samples, limiting the evidence base. Utilizing longitudinal administrative records from…

  19. The mediating effects of job satisfaction on turnover intention for long-term care nurses in Taiwan.

    Science.gov (United States)

    Kuo, Huai-Ting; Lin, Kuan-Chia; Li, I-Chuan

    2014-03-01

    This study explores the mediating effects of job satisfaction on work stress and turnover intention among long-term care nurses in Taiwan. Healthcare institutions face a nursing shortage, and it is important to examine the factors that influence turnover intention among nurses. Excessive levels of work stress may lead to employee dissatisfaction and a significant inverse relationship between work stress and job satisfaction, including subsequent effects on turnover among nurses. However, little is known about the mediating role of job satisfaction on work stress and turnover intention among long-term care nurses. A cross-sectional survey and a correlation design were used. Multistage linear regression was used to test the mediation model. This study showed that job satisfaction significantly mediated the relationship between work stress and turnover intention. Thirty-eight percent of the variance in turnover intention explained by work stress was accounted for by the mediation pathway. The results of this study showed that higher job satisfaction significantly decreased work stress and turnover intention among long-term care nurses. This study provides nursing administrators with a resource to build a supportive environment to increase nurses' job satisfaction and to decrease their stress and turnover. © 2013 John Wiley & Sons Ltd.

  20. Healthy looking hospital nurses showing vitamin d deficiency: correlation of vitamin d levels with their levels of parathhyroid hormone and bone turnover markers

    International Nuclear Information System (INIS)

    Nasim, A.; Salim, B.; Niazi, S.; Fatima, N.

    2015-01-01

    To evaluate the correlation of low vitamin D levels with parathyroid hormone (PTH) levels and bone turn over markers among apparently healthy hospital nurses. Methods: Screening was done on 50 recruited healthy female nursing staff, aged between 18 to 35 years, for vitamin D levels. Among them 31 were found to be deficient in vitamin D. These 31 nurses were selected for further evaluation in trance. Their vitamin D levels were calculated by using the electrochemiluminescence immunoassay. Blood samples were drawn to estimate serum PTH levels accordingly. Samples were also collected from these recruited subjects to evaluate their bone turn over markers, including, osteocalcin, procollagen type 1 N propeptide and Beta-Crosslaps. Results: Out of 50 subjects, 31 subjects were found to have Vitamin D levels below 50 nmol/l. Out of these 31 subjects, 13 subjects, 41.9%, showed vitamin D levels below 20 nmol/l. Among these 13 subjects, all had significantly raised PTH levels (p-value: <0.001, r-value: -0.781). In rest of all the subjects, including those having Vitamin D levels above 20nmol/l, inordinately, PTH levels were normal. No reciprocity was found between low Vitamin D and raised PTH levels with bone turnover markers, except with P1NP (r-value 0.022). Conclusion: PTH levels show a steep augmentation in serum, when vitamin D levels hit the trough below 20 nmol/l. These are the subjects who should be treated prior to the development of complications of bone resorption. Moreover we could not find any significant correlation of Vitamin D and PTH with any bone turnover marker except P1NP. (author)

  1. A multistudy examination of organizational stressors, emotional labor, burnout, and turnover in sport organizations.

    Science.gov (United States)

    Larner, R J; Wagstaff, C R D; Thelwell, R C; Corbett, J

    2017-12-01

    While a growing body of research has examined the types of organizational stressors encountered by individuals and their allied responses, little is known about how such individuals manage their emotional responses to these stressors or the consequences of such behaviors. This article presents novel findings from two studies examining the moderating role that emotional labor plays in the relationship between the frequency of organizational stressor experience, burnout, turnover intentions, and actual turnover in sport. In study 1, participants (n=487) completed measures of organizational stressors (OSI-SP), emotional labor (ELS), burnout (ABQ), and turnover intentions. In study 2, a 6-month longitudinal design was used to examine measures of organizational stressors (OSI-SP), emotional labor (ELS), turnover intentions, and actual turnover. Study 1 showed that surface acting moderated the relationship between the frequency of organizational stressors and burnout in sport. Further, surface acting acted as an important mechanism through which burnout mediated the relationship between the frequency of organizational stressors and turnover intentions. Study 2 showed that surface acting moderated the relationship between the organizational stressor frequency and turnover intentions-but not actual turnover-over time. These results highlight the importance of surface acting in understanding how individuals respond to organizational stressors encountered in sport, expanding our understanding of the positive and negative responses component of the meta-model of stress, emotions, and performance. These findings also highlight potentially deleterious emotion-management behaviors that practitioners might consider when aiming to support individuals encountering organizational stressors in sport. © 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  2. Ubiquitin in signaling and protein quality control

    DEFF Research Database (Denmark)

    Al-Saoudi, Sofie Vincents

    is related to the cancer-predisposition disease, Lynch syndrome. Of 24 different MSH2 variants, some of which have been linked to Lynch syndrome, we show that there is a strong correlation between the predicted structural stability and the protein half-life. We show that a predicted destabilization of 3 kcal....../mol is sufficient to cause proteasomal degradation of MSH2 variants. Importantly our calculations can, in addition to protein turnover, also predict pathogenicity of MSH2 variants, suggesting that this approach can be applied for Lynch syndrome diagnosis, and perhaps for other hereditary diseases....

  3. Reversal in the relationship between species richness and turnover in a phytoplankton community.

    Science.gov (United States)

    Matthews, Blake; Pomati, Francesco

    2012-11-01

    Negative relationships between species richness and the rate of compositional turnover are common, suggesting that diverse communities have greater stability than depauperate ones; however, the mechanistic basis for this pattern is still widely debated. Species richness and turnover can covary either because they are mechanistically linked or because they share common environmental drivers. Few empirical studies have combined long-term changes in community composition with multiple drivers of environmental change, and so little is known about how the underlying mechanisms of species coexistence interact with changes in the mean and variability of environmental conditions. Here, we use a 33 year long time series (1976-2008) of phytoplankton community composition from Lake Zurich, to examine how environmental variation influences the relationship between richness and annual turnover. We find that the relationship between richness and annual turnover reverses midway through the time series (1992-1993), leading to a hump-shaped relationship between species richness and annual turnover. Using structural equation modeling we show that annual turnover and diversity are independently associated with different drivers of environmental change. Furthermore, we find that the observed annual sequences of community assembly give rise to rates of species accumulation that are more heterogeneous through time than expected by chance, likely owing to a high proportion of species showing significant autocorrelation and to strong positive covariation in the occurrences of species.

  4. High Turnover of Tissue Factor Enables Efficient Intracellular Delivery of Antibody-Drug Conjugates

    DEFF Research Database (Denmark)

    de Goeij, Bart E.C.G.; Satijn, D.; Freitag, C. M.

    2015-01-01

    specificities. TF-ADC demonstrated effective killing against tumor cell lines with variable levels of target expression. In xenograft models, TF-ADC was relatively potent in reducing tumor growth compared with EGFR-and HER2-ADCs. We hypothesize that the constant turnover of TF on tumor cells makes this protein...

  5. Perceived Work Conditions and Turnover Intentions: The Mediating Role of Meaning of Work

    Science.gov (United States)

    Arnoux-Nicolas, Caroline; Sovet, Laurent; Lhotellier, Lin; Di Fabio, Annamaria; Bernaud, Jean-Luc

    2016-01-01

    Perceived working conditions lead to various negative outcomes for employee behaviors, including turnover intentions. Although potential mediators for these relationships were previously identified, the importance of meaning of work has not yet been investigated. This study examines the role of this psychological resource as a mediator for the relationships between perceived working conditions and turnover intentions in a sample of 336 French workers from different job contexts. Results show that adverse working conditions were positively and significantly associated with turnover intentions. Meaning of work is negatively related to both perceived working conditions and turnover intentions. Mediation analyses for meaning of work demonstrated indirect effects of several adverse working conditions on turnover intentions. The role of meaning of work as a psychological resource for employees facing adverse working conditions is discussed, especially regarding its implications for research and practice within organizational contexts. PMID:27242616

  6. Perceived Work Conditions and Turnover Intentions: The Mediating Role of Meaning of Work.

    Science.gov (United States)

    Arnoux-Nicolas, Caroline; Sovet, Laurent; Lhotellier, Lin; Di Fabio, Annamaria; Bernaud, Jean-Luc

    2016-01-01

    Perceived working conditions lead to various negative outcomes for employee behaviors, including turnover intentions. Although potential mediators for these relationships were previously identified, the importance of meaning of work has not yet been investigated. This study examines the role of this psychological resource as a mediator for the relationships between perceived working conditions and turnover intentions in a sample of 336 French workers from different job contexts. Results show that adverse working conditions were positively and significantly associated with turnover intentions. Meaning of work is negatively related to both perceived working conditions and turnover intentions. Mediation analyses for meaning of work demonstrated indirect effects of several adverse working conditions on turnover intentions. The role of meaning of work as a psychological resource for employees facing adverse working conditions is discussed, especially regarding its implications for research and practice within organizational contexts.

  7. Turnover of 14C-glucose in soils and its relationship with soil characters

    International Nuclear Information System (INIS)

    Ni Jinzhi; Xu Jianmin; Xie Zhengmiao; Ye Qingfu

    2001-01-01

    The turnover of 14 C-glucose added in 13 soils was studied. The turnover rate of 14 C-glucose can be divided into three phases: 0 - 3d, 3 - 28d and 28 - 294d. The range of the turnover rate and half -life of 14 C-glucose were 1.3 x 10 -1 - 2.5 x 10 -1 d -1 and 3 - 5d, 0.7x 10 -2 - 1.2 x 10 -2 d -1 and 58 - 97d, 0.5 x 10 -3 - 1.4 x 10 -3 d -1 and 491 - 1504d, respectively. Correlation analysis showed that from 0 to 3 days the turnover rate of 14 C-glucose had significant positive correlation with soil qCO 2 , from 3 to 28 days, the turnover rate of 14 C-glucose had no significant correlation with soil physico-chemical and biological properties. The turnover rate of 14 C-glucose had significant or highly significant negative correlation with soil total organic carbon, total nitrogen, CEC and significant positive correlation with soil sand content during the period from 28 to 294 days. Turnover of 14 C-glucose during the third period has close correlation with soil properties

  8. Does Enhancing Work-Time Control and Flexibility Reduce Turnover? A Naturally Occurring Experiment.

    Science.gov (United States)

    Moen, Phyllis; Kelly, Erin L; Hill, Rachelle

    2011-02-01

    We investigate the turnover effects of an organizational innovation (ROWE-Results Only Work Environment) aimed at moving away from standard time practices to focus on results rather than time spent at work. To model rates of turnover, we draw on survey data from a sample of employees at a corporate headquarters (N = 775) and institutional records of turnover over eight months following the ROWE implementation. We find the odds of turnover are indeed lower for employees participating in the ROWE initiative, which offers employees greater work-time control and flexibility, and that this is the case regardless of employees' gender, age, or family life stage. ROWE also moderates the turnover effects of organizational tenure and negative home-to-work spillover, physical symptoms, and job insecurity, with those in ROWE who report these situations generally less likely to leave the organization. Additionally, ROWE reduces turnover intentions among those remaining with the corporation. This research moves the "opting-out" argument from one of private troubles to an issue of greater employee work-time control and flexibility by showing that an organizational policy initiative can reduce turnover.

  9. Commitment Profiles and Employee Turnover

    Science.gov (United States)

    Stanley, Laura; Vandenberghe, Christian; Vandenberg, Robert; Bentein, Kathleen

    2013-01-01

    We examined how affective (AC), normative (NC), perceived sacrifice (PS), and few alternatives (FA) commitments combine to form profiles and determine turnover intention and turnover. We theorized that three mechanisms account for how profiles operate, i.e., the degree to which membership is internally regulated, the perceived desirability and…

  10. Stress and Protein Turnover in Lemna minor1

    Science.gov (United States)

    Cooke, Robert J.; Oliver, Jane; Davies, David D.

    1979-01-01

    Transfer of fronds of Lemna minor L. to adverse growth conditions or stress situations causes a lowering of the growth rate and a loss of soluble protein per frond, the extent of the loss being dependent on the nature of the stress. The loss or protein is due to two factors: (a) a decrease in the rate constant of protein synthesis (ks); (b) an increase in the rate constant of protein degradation (kd). In plants adapted to the stresses, protein synthesis increases and the initially rapid rate of proteolysis is reduced. Addition of abscisic acid both lowers ks and increases kd, whereas benzyladenine seems to alleviate the effects of stress on protein content by decreasing kd rather than by altering ks. Based on the measurement of enzyme activities, stress-induced protein degradation appears to be a general phenomenon, affecting many soluble proteins. The adaptive significance of stress-induced proteolysis is discussed. PMID:16661102

  11. Higher molecular weight dissolved organic nitrogen turnover as affected by soil management history

    DEFF Research Database (Denmark)

    Lønne Enggrob, Kirsten

    of different management histories on the turnover of high Mw DON. Further, we distinguished between several classes of high Mw DON, i.e., 1-10 kDa and >10 kDa. 3. Materials and methods With the use of micro-lysimeters, the turnover of triple-labeled (15N, 14C and 13C) high Mw DON was studied in a sandy soil......High molecular weight dissolved organic nitrogen turnover as affected by soil management history *Kirsten Lønne Enggrob,1 Lars Elsgaard,1 and Jim Rasmussen1 1Aarhus University, Dept. of Agroecology, Foulum, Denmark 1. Introduction Dissolved organic nitrogen (DON) play an important role in soil N...... are presented for 14CO2 evolution during 14 days of incubation. 4. Results and conclusion Results showed that the turnover rate of high Mw DON was dependent on both the Mw size of DON and on the soil liming history. Evidence showing where in the DON Mw sizes the bottleneck lies will be presented....

  12. On-call work and physicians' turnover intention: the moderating effect of job strain.

    Science.gov (United States)

    Heponiemi, Tarja; Presseau, Justin; Elovainio, Marko

    2016-01-01

    Physician shortage and turnover are major problems worldwide. On-call duties may be among the risk factors of high turnover rates among physicians. We investigated whether having on-call duties is associated with physicians' turnover intention and whether job strain variables moderate this association. The present study was a cross-sectional questionnaire study among 3324 (61.6% women) Finnish physicians. The analyses were conducted using analyses of covariance adjusted for age, gender, response format, specialization status and employment sector. The results showed that job strain moderated the association between being on-call and turnover intention. The highest levels of turnover intention were among those who had on-call duties and high level of job strain characterized by high demands and low control opportunities. The lowest levels of turnover intention were among those who were not on-call and who had low strain involving low demands and high control. Also, job demands moderated the association between being on-call and turnover intention; turnover intention levels were higher among those with on-call duties and high demands than those being on-call and low demands. To conclude, working on-call was related to physicians' turnover intention particularly in those with high job strain. Health care organizations should focus more attention on working arrangements and scheduling of on-call work, provide a suitable working pace and implement means to increase physicians' participation and control over their job.

  13. Intracellular protein breakdown. 8

    International Nuclear Information System (INIS)

    Bohley, P.; Kirschke, H.; Langner, J.; Wiederanders, B.; Ansorge, S.

    1976-01-01

    Double-labelled proteins from rat liver cytosol ( 14 C in long-lived, 3 H in short-lived proteins after in-vivo-labelling) are used as substrates for unlabelled proteinases in vitro. Differences in the degradation rates of short-lived and long-lived proteins in vitro by different proteinases and after addition of different effectors allow conclusions concerning their importance for the in-vivo-turnover of substrate proteins. The main activity (>90%) of soluble lysosomal proteinases at pH 6.1 and pH 6.9 is caused by thiolproteinases, which degrade preferentially short-lived cytosol proteins. These proteinases are inhibited by leupeptin. Autolysis of double-labelled cell fractions shows a remarkably faster breakdown of short-lived substrate proteins only in the soluble part of lysosomes. Microsomal fractions degrade in vitro preferentially long-lived substrate proteins. (author)

  14. Work Overload and Turnover Intention of Junior Auditors in Greater Jakarta, Indonesia

    Directory of Open Access Journals (Sweden)

    Andika Pradana

    2015-11-01

    Full Text Available This paper aims to analyze how work overload influences turnover intentions of newly hired junior auditors in public accounting offices. Job satisfaction, work related stress and work life conflicts are used as mediating variables between work overload and turnover intention. This study employed 141 auditors from several accounting firms operating in the Greater Jakarta region. The sample was selected using purposive sampling. Three mediation hypotheses were tested using Structural Equation Modeling (SEM. The results show that work overload has a significant effect on increasing turnover intention through both job satisfaction and work related stress. In comparison, work overload does not influence turnover intention through work life balance. This may be due to the nature of the respondents, in which a majority of the newly hired accountants employed in this study are unmarried.

  15. Nurse turnover: a literature review - an update.

    Science.gov (United States)

    Hayes, Laureen J; O'Brien-Pallas, Linda; Duffield, Christine; Shamian, Judith; Buchan, James; Hughes, Frances; Laschinger, Heather K Spence; North, Nicola

    2012-07-01

    Concerns related to the complex issue of nursing turnover continue to challenge healthcare leaders in every sector of health care. Voluntary nurse turnover is shown to be influenced by a myriad of inter-related factors, and there is increasing evidence of its negative effects on nurses, patients and health care organizations. The objectives were to conduct a comprehensive review of the related literature to examine recent findings related to the issue of nursing turnover and its causes and consequences, and to identify on methodological challenges and the implications of new evidence for future studies. A comprehensive search of the recent literature related to nursing turnover was undertaken to summarize findings published in the past six years. Electronic databases: MEDLINE, CINAHL and PubMed, reference lists of journal publications. Keyword searches were conducted for publications published 2006 or later that examined turnover or turnover intention in employee populations of registered or practical/enrolled or assistant nurses working in the hospital, long-term or community care areas. Literature findings are presented using an integrative approach and a table format to report individual studies. From about 330 citations or abstracts that were initially scanned for content relevance, 68 studies were included in this summary review. The predominance of studies continues to focus on determinants of nurse turnover in acute care settings. Recent studies offer insight into generational factors that should be considered in strategies to promote stable staffing in healthcare organizations. Nursing turnover continues to present serious challenges at all levels of health care. Longitudinal research is needed to produce new evidence of the relationships between nurse turnover and related costs, and the impact on patients and the health care team. Copyright © 2011 Elsevier Ltd. All rights reserved.

  16. Schistosoma mansoni; relationship between membrane turnover rates and susceptibility to immune damage. Part of a coordinated programme on preparation of irradiated vaccines against some human diseases

    International Nuclear Information System (INIS)

    Pereira Tavares, C.A.

    1983-11-01

    It is known that the schistosomulum of Schistosoma mansoni become refractory to damage by antibody and complement in vitro in the presence of serum, or Concanavalin A (Con A), or after contact with host tissues, presumably due to intrinsic changes in the surface membrane. This project studied the effect of dialysed fetal calf serum (DFCS) and Con A on the synthesis and turnover of individual proteins in the surface membrane using the incorporation of 14 C- and 3 H-labelled Arginine and the separation of the membrane proteins in SDS-PAGE. The results indicate that during the period in which schistosomules become resistant to immune attack, no qualitative alterations in electrophoretic patterns of surface proteins were observed. There was, however, a marked heterogeneity in synthesis and degradation among constituent proteins. In addition, Con A which had been shown to be effective in stimulating loss of susceptibility to immune attack, caused a slight decrease in the synthesis and turnover rate of high molecular weight proteins, whilst DFCS increased synthesis and turnover of low molecular weight proteins. This suggests that at least two processes occur in the membrane which may be related to the development of protection against immune attack. Serum might stimulate the loss of crucial antigens by accelerating their turnover making antibody attachment difficult, and Con A could be stabilizing the membrane by crosslinking large macromolecules. It is possible that in vivo both mechanisms occur to make the schistosomule surface refractory to damage

  17. An Exploration of Turnover Experience of IT Professionals in the District of Columbia

    Science.gov (United States)

    Edeh, George

    2016-01-01

    Turnover among information technology professionals costs organization in revenues. According to Computer Economics (2008), the cost of replacing one information technology employee is $50,000. Reports from the United States Department of Commerce and Office of Technology Policy showed that turnover rate in Information Technology has exceeded 20%…

  18. Selectivity in protein degradation during sporulation of Bacillus subtilis

    International Nuclear Information System (INIS)

    Mitani, Takahiko; Kadota, Hajime

    1976-01-01

    The breakdown of cellular protein was investigated in Bacillus subtilis ATCC 6051 labeled with glycine-2- 3 H or L-phenylalanine-U- 14 C at the different stages of vegetative growth and sporulation. The growth of the culture was determined by measuring optical density at 660 nm. The heat-resistant spores were scored by plating after heating at 80 deg C for 10 minutes. A question whether the turnover of glycine-labeled protein is similar to that of phenylalanine-labeled protein was experimentally studied. The patterns obtained with the glycine-labeled protein were different from those of phenylalanine-labeled protein. This was not multiple turnover. The cellular protein which was labeled with glycine at an early stage of sporulation showed rapid degradation, but the degradation of the protein labeled with glycine at later stages did not occur at all. Another question whether the labeled glycine incorporated into cells at the different stages of growth and sporulation was present in the spore coat fraction of matured spores was studied. Experiment demonstrated that the glycine incorporated into cells at the late sporulation stage was mainly utilized for the biosynthesis of the spore coat protein. These data suggest that the spore coat protein which contains relatively large amount of glycine is rarely subject to further degradation. (Iwakiri, K.)

  19. Metabolism of whole body protein in pregnant and non-pregnant gilts using 15N-glycine single-dose end-product method

    International Nuclear Information System (INIS)

    Wu De; Liu Huifang; Zhou Anguo; Wang Kangning; Yang Feng

    2007-01-01

    The metabolism of whole-body protein for pregnant and non-pregnant gilts was investigated using single-dose of 15 N-glycine end-product method. The results showed that there were no differences (P>0.05) in protein dynamic metabolism, amino acids utilization rate between pregnant and non-pregnant gilts at breeding. However, N flux, protein turnover rate, protein synthesis rate and breakdown rate of pregnant gilts were lower (P<0.05) than those of non-pregnant gilts at 30days after breeding, but the protein aggradiation's rate increased by 25% (P<0.05). During late gestation, N flux, protein turnover rate, protein synthesis rate and breakdown rate of pregnant sows were significantly increased (P<0.01), and protein aggradation's rate increased by 71.1%, compared with that of non-pregnant gilts. (authors)

  20. Dynamic structure of stock communities: a comparative study between stock returns and turnover rates

    Science.gov (United States)

    Su, Li-Ling; Jiang, Xiong-Fei; Li, Sai-Ping; Zhong, Li-Xin; Ren, Fei

    2017-07-01

    The detection of community structure in stock market is of theoretical and practical significance for the study of financial dynamics and portfolio risk estimation. We here study the community structures in Chinese stock markets from the aspects of both price returns and turnover rates, by using a combination of the PMFG and infomap methods based on a distance matrix. An empirical study using the overall data set shows that for both returns and turnover rates the largest communities are composed of specific industrial or conceptional sectors and the correlation inside a sector is generally larger than the correlation between different sectors. However, the community structure for turnover rates is more complex than that for returns, which indicates that the interactions between stocks revealed by turnover rates may contain more information. This conclusion is further confirmed by the analysis of the changes in the dynamics of community structures over five sub-periods. Sectors like banks, real estate, health care and New Shanghai take turns to comprise a few of the largest communities in different sub-periods, and more interestingly several specific sectors appear in the communities with different rank orders for returns and turnover rates even in the same sub-period. To better understand their differences, a comparison between the evolution of the returns and turnover rates of the stocks from these sectors is conducted. We find that stock prices only had large changes around important events while turnover rates surged after each of these events relevant to specific sectors, which shows strong evidence that the turnover rates are more susceptible to exogenous shocks than returns and its measurement for community detection may contain more useful information about market structure.

  1. Relationship between ICU nurses' moral distress with burnout and anticipated turnover.

    Science.gov (United States)

    Shoorideh, Foroozan Atashzadeh; Ashktorab, Tahereh; Yaghmaei, Farideh; Alavi Majd, Hamid

    2015-02-01

    Moral distress is one of intensive care unit nurses' major problems, which may happen due to various reasons, and has several consequences. Due to various moral distress outcomes in intensive care unit nurses, and their impact on nurses' personal and professional practice, recognizing moral distress is very important. The aim of this study was to determine correlation between moral distress with burnout and anticipated turnover in intensive care unit nurses. This study is a descriptive-correlation research. A total of 159 intensive care unit nurses were selected from medical sciences universities in Iran. Data collection instruments included "demographic questionnaire," "ICU Nurses' Moral Distress Scale," "Copenhagen Burnout Inventory" and "Hinshaw and Atwood Turnover Scale." Data analysis was done by using SPSS19. Informed consent from samples and research approval was obtained from Shahid Beheshti Medical Sciences University Research Ethics Board in Tehran. The findings showed intensive care unit nurses' moral distress and anticipated turnover was high, but burnout was moderate. The results revealed that there was a positive statistical correlation between intensive care unit nurses' age, their work experience and the fraction of nurses' number to number of intensive care unit beds with their moral distress and burnout. However, there were no correlation between gender, marriage status, educational degree and work shift and moral distress. Some of the findings of this research are consistent with other studies and some of them are inconsistent. Similarly, moral distress with burnout and anticipated turnover did not have statistical correlation. However, a positive correlation was found between burnout and anticipated turnover. The results showed that increase in the recruitment of young nurses, and nursing personnel, and diminishing intensive care unit nurses' moral distress, burnout and their turnover intention are essential. © The Author(s) 2014.

  2. Store turnover as a predictor of food and beverage provider turnover and associated dietary intake estimates in very remote Indigenous communities.

    Science.gov (United States)

    Wycherley, Thomas; Ferguson, Megan; O'Dea, Kerin; McMahon, Emma; Liberato, Selma; Brimblecombe, Julie

    2016-12-01

    Determine how very-remote Indigenous community (RIC) food and beverage (F&B) turnover quantities and associated dietary intake estimates derived from only stores, compare with values derived from all community F&B providers. F&B turnover quantity and associated dietary intake estimates (energy, micro/macronutrients and major contributing food types) were derived from 12-months transaction data of all F&B providers in three RICs (NT, Australia). F&B turnover quantities and dietary intake estimates from only stores (plus only the primary store in multiple-store communities) were expressed as a proportion of complete F&B provider turnover values. Food types and macronutrient distribution (%E) estimates were quantitatively compared. Combined stores F&B turnover accounted for the majority of F&B quantity (98.1%) and absolute dietary intake estimates (energy [97.8%], macronutrients [≥96.7%] and micronutrients [≥83.8%]). Macronutrient distribution estimates from combined stores and only the primary store closely aligned complete provider estimates (≤0.9% absolute). Food types were similar using combined stores, primary store or complete provider turnover. Evaluating combined stores F&B turnover represents an efficient method to estimate total F&B turnover quantity and associated dietary intake in RICs. In multiple-store communities, evaluating only primary store F&B turnover provides an efficient estimate of macronutrient distribution and major food types. © 2016 Public Health Association of Australia.

  3. Protein oxidation and peroxidation

    DEFF Research Database (Denmark)

    Davies, Michael Jonathan

    2016-01-01

    Proteins are major targets for radicals and two-electron oxidants in biological systems due to their abundance and high rate constants for reaction. With highly reactive radicals damage occurs at multiple side-chain and backbone sites. Less reactive species show greater selectivity with regard...... to the residues targeted and their spatial location. Modification can result in increased side-chain hydrophilicity, side-chain and backbone fragmentation, aggregation via covalent cross-linking or hydrophobic interactions, protein unfolding and altered conformation, altered interactions with biological partners...... and modified turnover. In the presence of O2, high yields of peroxyl radicals and peroxides (protein peroxidation) are formed; the latter account for up to 70% of the initial oxidant flux. Protein peroxides can oxidize both proteins and other targets. One-electron reduction results in additional radicals...

  4. Biotic turnover rates during the Pleistocene-Holocene transition

    Science.gov (United States)

    Stivrins, Normunds; Soininen, Janne; Amon, Leeli; Fontana, Sonia L.; Gryguc, Gražyna; Heikkilä, Maija; Heiri, Oliver; Kisielienė, Dalia; Reitalu, Triin; Stančikaitė, Miglė; Veski, Siim; Seppä, Heikki

    2016-11-01

    The Northern Hemisphere is currently warming at the rate which is unprecedented during the Holocene. Quantitative palaeoclimatic records show that the most recent time in the geological history with comparable warming rates was during the Pleistocene-Holocene transition (PHT) about 14,000 to 11,000 years ago. To better understand the biotic response to rapid temperature change, we explore the community turnover rates during the PHT by focusing on the Baltic region in the southeastern sector of the Scandinavian Ice Sheet, where an exceptionally dense network on microfossil and macrofossil data that reflect the biotic community history are available. We further use a composite chironomid-based summer temperature reconstruction compiled specifically for our study region to calculate the rate of temperature change during the PHT. The fastest biotic turnover in the terrestrial and aquatic communities occurred during the Younger Dryas-Holocene shift at 11,700 years ago. This general shift in species composition was accompanied by regional extinctions, including disappearance of mammoth (Mammuthus primigenius) and reindeer (Rangifer tarandus) and many arctic-alpine plant taxa, such as Dryas octopetala, Salix polaris and Saxifraga aizoides, from the region. This rapid biotic turnover rate occurred when the rate of warming was 0.17 °C/decade, thus slightly lower than the current Northern Hemisphere warming of 0.2 °C/decade. We therefore conclude that the Younger Dryas-Holocene shift with its rapid turnover rates and associated regional extinctions represents an important palaeoanalogue to the current high latitude warming and gives insights about the probable future turnover rates and patterns of the terrestrial and aquatic ecosystem change.

  5. THE EFFECT OF JOB SATISFACTION ON IT EMPLOYEES TURNOVER INTENTION IN ISRAEL

    Directory of Open Access Journals (Sweden)

    Ladelsky Limor

    2014-07-01

    Full Text Available Employee voluntary turnover is very costly for companies, particularly for the Hi-Tech sector, where the costs of their IT labor force is expensive. Employees\\' voluntary turnover has substantial negative impacts on the companies especially costs, potential loss of valuable knowledge, skills and organizational knowledge.That is why it becomes a critical issue to take address. Studies have been carried out on the reasons which lead to this tendency, however the ability to explain and predict it remains restricted.The objective of this paper is to present the reasons for voluntary turnover of employees in the IT sector in Israel from the IT employees` perspective. A broad analysis of the field literature led to the following groups of causes affecting voluntary turnover: organizational causes: Human Resource Management (HRM related, organizational culture, job related, leadership and internal marketing related; extra organizational causes: individual and, respectively, labor market related causes. This could be approached as n light of this review this article will focus on one of the extra organizational causes of voluntary turnover, i.e. the effect of job satisfaction on voluntary turnover intention among IT employees in Hi-Tech companies in Israel. This correlation was researched in an extensive empirical study among two population groups: IT employees and IT managers and by using mixed method research (combination of quantitative and qualitative research.The findings that supported the literature show job satisfaction has a negative effect on voluntary turnover intention among IT employees in Hi-Tech companies in Israel. Additionally, it was found that job satisfaction indirectly affects voluntary turnover intentions and that emotional variables such as commitment, motivation and loyalty mediate voluntary turnover intention.This finding is supported partially in the literature which only pointed out commitment as a mediating factor in the

  6. Degradation of protein translation machinery by amino acid starvation-induced macroautophagy

    DEFF Research Database (Denmark)

    Gretzmeier, Christine; Eiselein, Sven; Johnson, Gregory R.

    2017-01-01

    , unbiased approaches relying on quantitative mass spectrometry-based proteomics. Macroautophagy is induced by rapamycin treatment, and by amino acid and glucose starvation in differentially, metabolically labeled cells. Protein dynamics are linked to image-based models of autophagosome turnover. Depending...... on the inducing stimulus, protein as well as organelle turnover differ. Amino acid starvation-induced macroautophagy leads to selective degradation of proteins important for protein translation. Thus, protein dynamics reflect cellular conditions in the respective treatment indicating stimulus-specific pathways...

  7. Turnover of grain legume N rhizodeposits and effect of rhizodeposition on the turnover of crop residues

    DEFF Research Database (Denmark)

    Mayer, J.; Buegger, F.; Jensen, E.S.

    2004-01-01

    The turnover of N derived from rhizodeposition of faba bean (Vicia faba L.), pea (Pisum sativum L.) and white lupin (Lupinus albus L.) and the effects of the rhizodeposition on the subsequent C and N turnover of its crop residues were investigated in an incubation experiment (168 days, 15 degrees....... In the experiment the turnover of C and N was compared in soils with and without previous growth of three legumes and with and without incorporation of crop residues. After 168 days, 21% (lupin), 26% (faba bean) and 27% (pea) of rhizodeposition N was mineralised in the treatments without crop residues. A smaller...... amount of 15-17% was present as microbial biomass and between 30 and 55% of mineralised rhizodeposition N was present as microbial residue pool, which consists of microbial exoenzymes, mucous substances and dead microbial biomass. The effect of rhizodeposition on the C and N turnover of crop residues...

  8. Microbial degradation of dissolved proteins in seawater

    International Nuclear Information System (INIS)

    Hollibaugh, J.T.; Azam, F.

    1983-01-01

    An experimental protocol using radiolabeled proteins was developed to investigate the rates and mechanisms whereby dissolved proteins are degraded in natural marine plankton communities. The results of field observations and laboratory experiments indicate that proteins are degraded by a particle-bound, thermolabile system, presumably bacteria-associated enzymes, with an apparent half-saturation constant of ca. 25 μg bovine serum albumin (BSA) per liter. Gel permeation chromatography indicated that peptides of chain length intermediate between BSA and the final products of degradation (MW<700) do not accumulate in the medium. Competition experiments indicate that the system is relatively nonspecific. Turnover rates for the protein pool in samples collected in the Southern California Bight were of the same order of magnitude as the turnover rate of the L-leucine pool and were correlated with primary productivity, chlorophyll a concentrations, bacterial abundance and biomass, and L-leucine turnover rate. These data suggest that amino acids derived from proteins are utilized preferentially and do not completely mix with the amino acids in the bulk phase

  9. WORK OVERLOAD AND TURNOVER INTENTION OF JUNIOR AUDITORS IN GREATER JAKARTA, INDONESIA

    Directory of Open Access Journals (Sweden)

    Andika Pradana

    2015-11-01

    Full Text Available This paper aims to analyze how work overload influences turnover intentions of newly hired junior auditors in public accounting offices. Job satisfaction, work related stress and work life conflicts are used as mediating variables between work overload and turnover intention. This study employed 141 auditors from several accounting firms operating in the Greater Jakarta region. The sample was selected using purposive sampling. Three mediation hypotheses were tested using Structural Equation Modeling (SEM. The results show that work overload has a significant effect on increas- ing turnover intention through both job satisfaction and work related stress. In comparison, work overload does not influence turnover intention through work life balance. This may be due to the nature of the respondents, in which a majority of the newly hired accountants employed in this study are unmarried.

  10. Cell kinetics of the marine sponge Halisarca caerulea reveal rapid cell turnover and shedding

    NARCIS (Netherlands)

    Goeij, de J.M.; Kluijver, de A.; Duyl, van F.C.; Vacelet, J.; Wijffels, R.H.; Goeij, de A.F.P.M.; Cleutjens, J.P.M.; Schutte, B.

    2009-01-01

    This study reveals the peculiar in vivo cell kinetics and cell turnover of the marine sponge Halisarca caerulea under steady-state conditions. The tropical coral reef sponge shows an extremely high proliferation activity, a short cell cycle duration and massive cell shedding. Cell turnover is

  11. The incorporation of 2-[14C]glycine into porcine lens protein

    International Nuclear Information System (INIS)

    Lee, Y.B.; Kauffman, R.G.; DeVenecia, G.

    1977-01-01

    A series of experiments was conducted to estimate the apparent turnover rate of lens soluble protein, the incorporation rate of 2-[ 14 C]glycine into various soluble protein components and the effect of nutritional stress on the disappearance of radioactivity with time. Evidence is presented that there are two fractions of soluble lens protein with different turnover rates: one is a fast turnover fraction with a half-life of 20.8 hr and the other is a metabolically inert fraction with an infinitely long half-life. It is postulated that the fast turnover fraction is present in the newly-formed younger fibers in the periphery, whereas the inert fraction is in the old lens fibers of the cortex and nucleus. Sephadex G-200 column chromatography was used to separate the soluble lens protein into four components: A, B, C and D in the order of elution. The changes in specific activities of the four components with the time course after injection were followed. Prolonged starvation did not affect the disappearance of carbon incorporated into lens protein with the time course after injection, suggesting normal synthesis and degradation of lens protein without regard to dietary stress. (author)

  12. Antecedents of Norwegian Beginning Teachers' Turnover Intentions

    Science.gov (United States)

    Tiplic, Dijana; Brandmo, Christian; Elstad, Eyvind

    2015-01-01

    This study aims at exploring several individual, organizational, and contextual factors that may affect beginning teachers' turnover intentions during their first years of practice. The sample consists of 227 beginning teachers (69% female and 31% male) from 133 schools in Norway. The results show four important antecedents of beginning teachers'…

  13. KORELASI ANTARA EMPLOYEES INVOLVEMENT, TURNOVER SERTA PENGARUHNYA TERHADAP PRODUKTIVITAS

    Directory of Open Access Journals (Sweden)

    Purnawan Adi Wicaksono

    2012-02-01

    Full Text Available Praktek yang berkembang menyatakan bahwa employee involvement memiliki efek positif terhadap kinerja organisasi. Perubahan pada kultur organisasi dapat menimbulkan dampak berkurangnya absen, turnover, pengambilan keputusan yang lebih baik dan sebagainya. Sehingga menarik untuk diteliti apakah ada korelasi antara aplikasi perubahan organisasi yaitu employee involvement, turnover serta produktivitas Berdasarkan studi literatur didapatkan hubungan antara employee involvement dengan level turnover, serta hubungan turnover dengan produktivitas. Sehingga employee involvement dapat digunakan sebagai salah satu aspek menghitung produktivitas Keyword : employee involvement, turnover, produktivitas

  14. The Teacher Labour Market, Teacher Turnover and Disadvantaged Schools: New Evidence for England

    Science.gov (United States)

    Allen, Rebecca; Burgess, Simon; Mayo, Jennifer

    2018-01-01

    We study the market for teachers in England, in particular teacher turnover. We show that there is a positive raw association between the level of school disadvantage and the turnover rate of its teachers. This association diminishes as we control for school, pupil and local teacher labour market characteristics, but is not eliminated. The…

  15. Helicase properties of the Escherichia coli UvrAb protein complex

    International Nuclear Information System (INIS)

    Oh, E.Y.; Grossman, L.

    1987-01-01

    The Escherichia coli UvrA protein has an associated ATPase activity with a turnover number affected by the presence of UvrB protein as well as by DNA. Specifically, the structure of DNA significantly influences the turnover rate of the UvrAB ATPase activity. Double-stranded DNA maximally activates the turnover rate 10-fold whereas single-stranded DNA maximally activates the turnover rate 20-fold, suggesting that the mode of interaction of UvrAB protein with different DNAs is distinctive. We have previously shown that the UvrAB protein complex, driven by the binding energy of ATP, can locally unwind supercoiled DNA. The nature of the DNA unwinding activity and single-stranded DNA activation of ATPase activity suggest potential helicase activity. In the presence of a number of helicase substrates, the UvrAB complex, indeed, manifests a strand-displacement activity-unwinding short duplexes and D-loop DNA, thereby generating component DNA structures. The energy for the activity is derived from ATP or dATP hydrolysis. Unlike the E. coli DnaB, the UvrAB helicase is sensitive to UV-induced photoproducts

  16. The Link between HR Attributions and Employees’ Turnover Intentions

    Directory of Open Access Journals (Sweden)

    Juliana Caesaria Tandung

    2016-02-01

    Full Text Available Human Resources Management (HRM is part of the organizational functions that contribute to the effectiveness of a firm’s performance, and brings an organization a competitive advantage through the implementation of its Human Resources (HR practices. HR practices adopted by management are perceived or attributed subjectively by individual employees, and can in turn affect the employees’ attitudes and behavior (e.g. Job satisfaction and turnover intention. The purpose of this study is to contribute to the process-based approach by investigating the effect of HR attributions on turnover intentions, with job satisfaction playing a mediating role. The analysis is on the individual level, with 454 respondents from various organizations within the Netherlands. The results show that HR attributions can affect the turnover intention, through the presence of job satisfaction. Thus, it can be said that it is important to always consider the employees’ attitudes and behavior when examining their perception of HR practices, and in predicting their intention to leave.

  17. Turnover intention among Italian nurses: the moderating roles of supervisor support and organizational support.

    Science.gov (United States)

    Galletta, Maura; Portoghese, Igor; Penna, Maria Pietronilla; Battistelli, Adalgisa; Saiani, Luisa

    2011-06-01

    The purpose of this study was to examine the variables that are related to person-environment fit in Italian nurses, highlighting the role of supervisor support and organizational support in the relationship between nurses' perceptions of care adequacy, job satisfaction, and turnover intention. Therefore, 1240 nurses from three hospitals completed a self-administered questionnaire. The results showed that supervisor support and organizational support act differently as moderators of the care adequacy-job satisfaction-turnover intention relationship. Finally, job satisfaction was a mediating variable between care adequacy and turnover intention. These findings have important implications for hospitals because they help to promote effective work environments and to reduce turnover intention. © 2011 Blackwell Publishing Asia Pty Ltd.

  18. Rethinking Teacher Turnover: Longitudinal Measures of Instability in Schools

    Science.gov (United States)

    Holme, Jennifer Jellison; Jabbar, Huriya; Germain, Emily; Dinning, John

    2018-01-01

    While there is a robust literature examining the patterns and causes of teacher turnover, few articles to date have critically examined the measures of turnover used in these studies. Yet, an assessment of the way turnover is measured is important, as the measures become the means by which the "problem" of turnover becomes defined and…

  19. Earnings Management Surrounding CEO Turnover: Evidence from Korea

    OpenAIRE

    JONG-SEO CHOI; YOUNG-MIN KWAK; CHONGWOO CHOE

    2012-01-01

    This article examines the empirical relation between CEO turnover and earnings management in Korea using a sample of 317 CEO turnovers and 634 non-turnover control firms during the period of 2001-2008. We classify CEO turnovers into four types depending on whether the departure of outgoing CEO is peaceful or forced and the incoming CEO is promoted from within or recruited from outside the firm. We measure earnings management by both discretionary accruals and real activities management. We al...

  20. Thiamine content and turnover rates of some rat nervous regions, using labeled thiamine as a tracer

    International Nuclear Information System (INIS)

    Rindi, G.; Patrini, C.; Comincioli, V.; Reggiani, C.

    1980-01-01

    The content of total thiamine radioactivity in some nervous structures and liver of the rat was determined in a steady state condition, using [thiazole-2- 14 C]thiamine as a tracer. The contents were analyzed by a mamillary type compartmental model which enabled the authors to calculate the influx and efflux fractional rate constants, turnover times, turnover rates and relative accuracy. The results show in general a good agreement between turnover rate values and brain regional sensitivity to thiamine deficiency, the most vunerable areas to thiamine depletion being those with the highest turnover rates. (Auth.)

  1. Bacterial protein meal in diets for pigs and minks

    DEFF Research Database (Denmark)

    Hellwing, Anne Louise Frydendahl; Tauson, Anne-Helene; Skrede, Anders

    2007-01-01

    The effect of increasing the dietary content of bacterial protein meal (BPM) on protein turnover rate, and on nucleic acid and creatinine metabolism in growing minks and pigs was investigated in two experiments. In each experiment, 16 animals were allocated to four experimental diets. The diets...... containing no BPM served as controls, i.e. for minks diet M1, for pigs P1; the experimental diets contained increasing levels of BPM to replace fish meal (minks) or soybean meal (pigs), so that up to 17% (P2), 20% (M2), 35% (P3), 40% (M3), 52% (P4), and 60% (M4) of digestible N was BPM derived. Protein...... turnover rate was measured by means of the end-product method using [15N]glycine as tracer and urinary nitrogen as end-product. In minks, protein flux, synthesis, and breakdown increased significantly with increasing dietary BPM. In pigs, diet had no observed effect on protein turnover rate. The intake...

  2. Turn-over of Stratijm Corneum in Leprosy

    Directory of Open Access Journals (Sweden)

    R P Okhandiar

    1987-01-01

    Full Text Available Stratum corneum showed increased proliferative activity on the patches of leprosy as evidenced by a significantly fast stratum corneum turnover time (p 0.001 measured by fluorescent staining technic with dansyl chloride. These findings suggest imperfect keratinization on the patches of leprosy leading to formation of structurally weak stratum corneum.

  3. Water turnover rate and its metabolism in defaunated, refaunated and faunated male buffalo calves

    International Nuclear Information System (INIS)

    Chaudhary, L.C.; Srivastava, Arun

    1993-01-01

    In tropical countries like India, environment climatic conditions are variable throughout the year ranging from favourable to very hostile. The high temperature and humidity and often limited supply of water causes low productivity of livestock even when good quality of feed is supplied in required quantity. The turnover rate of water is related to environmental temperature, feed supply, protein or electrolyte content of the diet and also on physiological status of the animals.In the present experiment tritiated water dilution technique was used in an attempt to study the effect of removing ciliate protozoa from the rumen (defaunation) on water metabolism and its turnover rate in buffalo calves given wheat straw and concentrate mixture. (author). 18 refs., 2 tabs

  4. Workforce turnover at local health departments: nature, characteristics, and implications.

    Science.gov (United States)

    Newman, Sarah J; Ye, Jiali; Leep, Carolyn J

    2014-11-01

    Employee turnover, defined as total separations from employment, is expensive, can result in lost capacity, and can limit local health departments' (LHDs') ability to respond to public health needs. Despite the importance of workforce capacity in public health, little is known about workforce turnover in LHDs. To examine the extent to which LHDs experience turnover and identify LHD characteristics that are associated with turnover. A cross-sectional data set of employee turnover and LHD characteristics from the 2013 National Profile of LHDs was analyzed. Descriptive statistics and bivariate analyses were conducted in 2014 on turnover rates. The effect of the following LHD characteristics on turnover rates were examined: population size, governance type, degree of urbanization, top executive experience level, expenditures per capita, and LHD budget cuts. In 2013, LHDs experienced a mean turnover rate of 9.88%; approximately one third of turnover was due to retirements. LHDs with shared state and local governance experienced a higher turnover rate than LHDs with exclusive state or local governance. LHDs that are units of state agencies had a significantly higher retirement rate than those governed by local authorities. Top executive experience level, per capita expenditures, and LHD budget cuts were also related to turnover rates. LHDs experienced a lower overall turnover rate than state health departments in 2011 and lower than all local and state government agencies in 2012. Strengthening leadership skills of new top executives and ensuring adequate funding may reduce turnover in LHDs. Copyright © 2014 American Journal of Preventive Medicine. Published by Elsevier Inc. All rights reserved.

  5. The relationship between family-to-work conflict of employee and co-workers' turnover intention

    Directory of Open Access Journals (Sweden)

    Tavakol Sharafi

    2012-01-01

    Full Text Available Previous studies have convincingly shown that employees' family lives can affect their work outcomes. We investigate whether family-to-work conflict (FWC experienced by the employee also affects the turnover intention of a co-worker. We predict that the employee's FWC has an effect on the co-worker's turnover intention through the crossover of positive and negative work attitudes. Using a sample of 154 co-worker dyads, we found that the employee FWC was positively related to co-worker turnover intention through the crossover of (reduced work engagement. Results show that family matters at work, affecting employee. In addition, employee's job engagement was positively related to his (her co-worker job engagement and it was negatively related co-worker turnover intention and employee's FWC was not positively related to co-worker turnover intention trough the crossover of (reduced feelings of engagement.

  6. High School Band Students' Perspectives of Teacher Turnover

    Science.gov (United States)

    Kloss, Thomas E.

    2013-01-01

    Teacher turnover remains an important issue in education. The least researched perspectives, though, are those of the students who experience teacher turnover. The purpose of this study was to examine how high school band students experience teacher turnover. A total of twelve students were interviewed, representing three schools that experienced…

  7. Turnover in health care: the mediating effects of employee engagement.

    Science.gov (United States)

    Collini, Stevie A; Guidroz, Ashley M; Perez, Lisa M

    2015-03-01

    This study aimed to understand the interaction between interpersonal respect, diversity climate, mission fulfilment and engagement to better predict turnover in health care. Registered nurse turnover has averaged 14% and current nursing shortages are expected to spread. Few studies have studied employee engagement as a mediator between organisational context and turnover. Study participants were employees working within 185 departments across ten hospitals within a large healthcare organisation in the USA. Although a total of 5443 employees work in these departments, employee opinion survey responses were aggregated by department before being linked to turnover rates gathered from company records. Engagement fully mediated the relationship between respect and turnover and the relationship between mission fulfilment and turnover. Diversity climate was not related to turnover. Turnover in health care poses a significant threat to the mission of creating a healing environment for patients and these results demonstrate that workplace respect and connection to the mission affect turnover by decreasing engagement. The findings demonstrated that to increase engagement, and improve turnover rates in health care, it would be beneficial for organisations, and nurse management to focus on improving mission fulfilment and interpersonal relationships. © 2013 John Wiley & Sons Ltd.

  8. Numbers of simultaneous turnovers calculated from anesthesia or operating room information management system data.

    Science.gov (United States)

    Dexter, Franklin; Marcon, Eric; Aker, John; Epstein, Richard H

    2009-09-01

    More personnel are needed to turn over operating rooms (ORs) promptly when there are more simultaneous turnovers. Anesthesia and/or OR information management system data can be analyzed statistically to quantify simultaneous turnovers to evaluate whether to add an additional turnover team. Data collected for each case at a six OR facility were room, date of surgery, time of patient entry into the OR, and time of patient exit from the OR. The number of simultaneous turnovers was calculated for each 1 min of 122 4-wk periods. Our end point was the reduction in the daily minutes of simultaneous turnovers exceeding the number of teams caused by the addition of a team. Increasing from two turnover teams to three teams reduced the mean daily minutes of simultaneous turnovers exceeding the numbers of teams by 19 min. The ratio of 19 min to 8 h valued the time of extra personnel as 4.0% of the time of OR staff, surgeons, and anesthesia providers. Validity was suggested by other methods of analyses also suggesting staffing for three simultaneous turnovers. Discrete-event simulation showed that the reduction in daily minutes of turnover times from the addition of a team would likely match or exceed the reduction in the daily minutes of simultaneous turnovers exceeding the numbers of teams. Confidence intervals for daily minutes of turnover times achieved by increasing from two to three teams were calculated using successive 4-wk periods. The distribution was sufficiently close to normal that accurate confidence intervals could be calculated using Student's t distribution (Lilliefors' test P = 0.58). Analysis generally should use 13 4-wk periods as increasing the number of periods from 6 to 13 significantly reduced the coefficient of variation of the averages but not increasing the number of periods from 6 to 9 or from 9 to 13. The number of simultaneous turnovers can be calculated for each 1 min over 1 yr. The reduction in the daily minutes of simultaneous turnovers

  9. Turnover Time

    Science.gov (United States)

    Ecosystems contain energy and materials such as carbon, nitrogen, phosphorus, and water, and are open to their flow-through. Turnover time refers to the amount of time required for replacement by flow-through of the energy or substance of interest contained in the system, and is ...

  10. Emergency room nurses' pathway to turnover intention: a moderated serial mediation analysis.

    Science.gov (United States)

    Bruyneel, Luk; Thoelen, Tom; Adriaenssens, Jef; Sermeus, Walter

    2017-04-01

    The aim of this study was to explore the association between the quality of the work environment, job characteristics, demographic characteristics and a pathway of job satisfaction, emotional exhaustion and turnover intention among nurses in emergency departments and perform subgroup analyses. Turnover intention among nurses is high. Multiple causes have been described, mostly in large studies of nurses working on general wards, often without considering complementarity of conceptual models and showing scant interest in the consistency of associations across subgroups of nurses. Cross-sectional multicentre survey. Convenience sample of 294 nurses in 11 Belgian emergency departments during 2014-2015. Indirect effects in the form of mediation and serial mediation were estimated to assess the association between work environment (Magnet model), job characteristics (Job Demand Control Support model) and turnover intention via job satisfaction and emotional exhaustion. Consistency of these indirect effects across subgroups of nurses was examined using moderated mediation analysis (conditional indirect effects). Several Magnet and Job Demand Control Support dimensions were related to turnover intention, either via job dissatisfaction (mediation) or via job satisfaction and emotional exhaustion (serial mediation). In the case of social support from supervisor, these indirect effects were only significant for female nurses, among whom turnover intention was higher. Last, nurses with more years of experience were less likely to indicate turnover intention. To maximize prevention of turnover intention at emergency departments, interventions could target early career nurses, work environment and job characteristics. Female nurses in particular may also benefit from improved social support from their supervisor. © 2016 John Wiley & Sons Ltd.

  11. Role of work overload toward turnover intention among newly hired public accountants

    OpenAIRE

    Pradana, Andika; Salehudin, Imam

    2013-01-01

    This paper aims to analyze how work overload influences turnover intentions of newly hired public accountants. Job satisfaction, work related stress and work life conflicts are used as mediating variable between work overload and turnover intention. This study employed 141 auditors from several accounting firms operating in the Greater Jakarta region. Six proposed hypotheses was tested using Structural Equation Modeling (SEM). Results showed that work overload has significant effect in increa...

  12. Pitfalls in quantifying species turnover: the residency effect

    Directory of Open Access Journals (Sweden)

    Kevin Chase Burns

    2014-03-01

    Full Text Available The composition of ecological communities changes continuously through time and space. Understanding this turnover in species composition is a central goal in biogeography, but quantifying species turnover can be problematic. Here, I describe an underappreciated source of bias in quantifying species turnover, namely ‘the residency effect’, which occurs when the contiguous distributions of species across sampling domains are small relative to census intervals. I present the results of a simulation model that illustrates the problem theoretically and then I demonstrate the problem empirically using a long-term dataset of plant species turnover on islands. Results from both exercises indicate that empirical estimates of species turnover may be susceptible to significant observer bias, which may potentially cloud a better understanding of how the composition of ecological communities changes through time.

  13. Effect of white striping myopathy on breast muscle (Pectoralis major) protein turnover and gene expression in broilers.

    Science.gov (United States)

    Vignale, Karen; Caldas, Justina V; England, Judy A; Boonsinchai, Nirun; Magnuson, Andrew; Pollock, Erik D; Dridi, Sami; Owens, Casey M; Coon, Craig N

    2017-04-01

    A study was conducted to evaluate the effect of white striping ( ) of broiler breast muscle ( Pectoralis major ) on protein turnover and gene expression of genes related to protein degradation and fatty acid synthesis. A total of 560 day-old male broiler chicks Cobb 500 were allocated in a total of 16 pens, 35 chicks per pen. A completely randomized design was conducted with a 2 × 3 factorial arrangement (2 scores: severe and normal, and 3 breast meat samples sites). At d 60, 20 birds were randomly selected, euthanized, and scored for white striping. Scoring was either normal ( , no WS) or severe ( ). Also, the same day, 17 birds (16 infused, one control) were randomly selected and infused with a solution of 15 N Phen 40% ( ). Breast muscle tissue was taken for gene expression analysis of the following genes: MuRF1, atrogin-1, IGF-1, insulin receptor ( ), fatty acid synthetase, and acetyl CoA carboxylase ( ). Each bird was humanely euthanized after 10 minutes of infusion and scored for WS (NORM or SEV). Samples of the breast muscle ( Pectoralis major ) were taken at different layers (3 samples per bird: ventral, medial, dorsal), along with a sample of excreta for 3-methylhistidine analysis. Out of the 16 breast samples taken, only 10 were selected for analysis based on the WS score (5 NORM and 5 SEV). No significant differences ( P > 0.05) were found in fractional synthesis rate ( ) between SEV WS, NORM and sample sites for breast meat. However, fractional breakdown rate ( ) was significantly higher in birds with SEV WS compared to NORM (8.2 and 4.28, respectively, P white striping are degrading more muscular protein and mobilizing more fat. © 2016 Poultry Science Association Inc.

  14. Scale dependence in species turnover reflects variance in species occupancy.

    Science.gov (United States)

    McGlinn, Daniel J; Hurlbert, Allen H

    2012-02-01

    Patterns of species turnover may reflect the processes driving community dynamics across scales. While the majority of studies on species turnover have examined pairwise comparison metrics (e.g., the average Jaccard dissimilarity), it has been proposed that the species-area relationship (SAR) also offers insight into patterns of species turnover because these two patterns may be analytically linked. However, these previous links only apply in a special case where turnover is scale invariant, and we demonstrate across three different plant communities that over 90% of the pairwise turnover values are larger than expected based on scale-invariant predictions from the SAR. Furthermore, the degree of scale dependence in turnover was negatively related to the degree of variance in the occupancy frequency distribution (OFD). These findings suggest that species turnover diverges from scale invariance, and as such pairwise turnover and the slope of the SAR are not redundant. Furthermore, models developed to explain the OFD should be linked with those developed to explain species turnover to achieve a more unified understanding of community structure.

  15. Protein Turnover and Cellular Stress in Mildly and Severely Affected Muscles from Patients with Limb Girdle Muscular Dystrophy Type 2I

    DEFF Research Database (Denmark)

    Hauerslev, Simon; Sveen, Marie-Louise; Vissing, John

    2013-01-01

    Patients with Limb girdle muscular dystrophy type 2I (LGMD2I) are characterized by progressive muscle weakness and wasting primarily in the proximal muscles, while distal muscles often are spared. Our aim was to investigate if wasting could be caused by impaired regeneration in the proximal...... by using the developmental markers embryonic myosin heavy chain (eMHC) and neural cell adhesion molecule (NCAM) and also assessing satellite cell activation status by myogenin positivity. Severe muscle histopathology was occasionally observed in the proximal muscles of patients with LGMD2I whereas distal...... highly increased in severely affected muscles compared to mildly affected muscles. Our results indicate that alterations in the protein turnover and myostatin levels could progressively impair the muscle mass maintenance and/or regeneration resulting in gradual muscular atrophy....

  16. Leaf and fine root carbon stocks and turnover are coupled across Arctic ecosystems.

    Science.gov (United States)

    Sloan, Victoria L; Fletcher, Benjamin J; Press, Malcolm C; Williams, Mathew; Phoenix, Gareth K

    2013-12-01

    Estimates of vegetation carbon pools and their turnover rates are central to understanding and modelling ecosystem responses to climate change and their feedbacks to climate. In the Arctic, a region containing globally important stores of soil carbon, and where the most rapid climate change is expected over the coming century, plant communities have on average sixfold more biomass below ground than above ground, but knowledge of the root carbon pool sizes and turnover rates is limited. Here, we show that across eight plant communities, there is a significant positive relationship between leaf and fine root turnover rates (r(2) = 0.68, P turnover rates of both leaf (r(2) = 0.63, P community scale. These ecological relationships not only demonstrate close links between above and below-ground plant carbon dynamics but also allow plant carbon pool sizes and their turnover rates to be predicted from the single readily quantifiable (and remotely sensed) parameter of LAI, including the possibility of estimating root data from satellites. © 2013 John Wiley & Sons Ltd.

  17. Turnover and vacancy rates for registered nurses: do local labor market factors matter?

    Science.gov (United States)

    Rondeau, Kent V; Williams, Eric S; Wagar, Terry H

    2008-01-01

    Turnover of nursing staff is a significant issue affecting health care cost, quality, and access. In recent years, a worldwide shortage of skilled nurses has resulted in sharply higher vacancy rates for registered nurses in many health care organizations. Much research has focused on the individual, group, and organizational determinants of turnover. Labor market factors have also been suggested as important contributors to turnover and vacancy rates but have received limited attention by scholars. This study proposes and tests a conceptual model showing the relationships of organization-market fit and three local labor market factors with organizational turnover and vacancy rates. The model is tested using ordinary least squares regression with data collected from 713 Canadian hospitals and nursing homes. Results suggest that, although modest in their impact, labor market and the organization-market fit factors do make significant yet differential contributions to turnover and vacancy rates for registered nurses. Knowledge of labor market factors can substantially shape an effective campaign to recruit and retain nurses. This is particularly true for employers who are perceived to be "employers-of-choice."

  18. An application of Six Sigma methodology to turnover intentions in health care.

    Science.gov (United States)

    Taner, Mehmet

    2009-01-01

    The purpose of this study is to show how the principles of Six Sigma can be applied to the high turnover problem of doctors in medical emergency services and paramedic backup. Six Sigma's define-measure-analyse-improve-control (DMAIC) is applied for reducing the turnover rate of doctors in an organisation operating in emergency services. Variables of the model are determined. Explanatory factor analysis, multiple regression, analysis of variance (ANOVA) and Gage R&R are employed for the analysis. Personal burnout/stress and dissatisfaction from salary were found to be the "vital few" variables. The organisation took a new approach by improving its initiatives to doctors' working conditions. Sigma level of the process is increased. New policy and process changes have been found to effectively decrease the incidence of turnover intentions. The improved process is gained, standardised and institutionalised. This study is one of the few papers in the literature that elaborates the turnover problem of doctors working in the emergency and paramedic backup services.

  19. Nurse turnover: the mediating role of burnout.

    Science.gov (United States)

    Leiter, Michael P; Maslach, Christina

    2009-04-01

    This study tested whether the mediation model of burnout could predict nurses' turnover intentions. A better understanding of what factors support a commitment to a nursing career could inform both policies and workplace practices. The mediation model of burnout provides a way of linking the quality of a nurse's worklife to various outcomes, such as turnover. Data on areas of worklife, burnout, and turnover intentions were collected by surveying 667 Canadian nurses in the Atlantic Provinces. The findings supported the mediation model of burnout, in which areas of worklife predicted burnout, which in turn predicted turnover intentions. Cynicism was the key burnout dimension for turnover, and the most critical areas of worklife were value conflicts and inadequate rewards. The results of this study provide some new insights into how the intention of nurses to leave their job is related to particular aspects of their worklife and to burnout. These results suggest what may be the most appropriate areas to target for interventions to reduce the risk of nurses exiting early from their chosen career.

  20. AN ECONOMETRIC APPROACH ABOUT VOLUNTARY TURNOVER

    Directory of Open Access Journals (Sweden)

    ADALET EREN

    2013-06-01

    Full Text Available This study analyzes individual and organizational variables that affect voluntary turnover are determined in the special defence and security companies. A binomial logistic regression model is used to estimate voluntary turnover.  Binomial Logistic regression, reliability test (scale alfa, variance (ANOVA, Post-hoc/Tukey, correlation (Pearson and other basic statistical techniques  with SPSS 13 statistical packet program was used in the analyzes ofresearch data. The study finds that; situation of suppose working, number of child, number of death child, number of home’s moving, support of rent, total monthly income of household, last work’s region, number of prizes, affect voluntary turnover are determined.

  1. Age-related collagen turnover of the interstitial matrix and basement membrane: Implications of age- and sex-dependent remodeling of the extracellular matrix

    DEFF Research Database (Denmark)

    Kehlet, Stephanie N.; Willumsen, Nicholas; Armbrecht, Gabriele

    2018-01-01

    The extracellular matrix (ECM) plays a vital role in maintaining normal tissue function. Collagens are major components of the ECM and there is a tight equilibrium between degradation and formation of these proteins ensuring tissue health and homeostasis. As a consequence of tissue turnover, small...... collagen fragments are released into the circulation, which act as important biomarkers in the study of certain tissue-related remodeling factors in health and disease. The aim of this study was to establish an age-related collagen turnover profile of the main collagens of the interstitial matrix (type I...... an increased turnover. In summary, collagen turnover is affected by age and sex with the interstitial matrix and the basement membrane being differently regulated. The observed changes needs to be accounted for when measuring ECM related biomarkers in clinical studies....

  2. Glutathione turnover in 14 rat tissues

    International Nuclear Information System (INIS)

    Potter, D.W.; Tran, T.

    1990-01-01

    GSH is a tripeptide found in all tissues and is important in maintaining cellular redox status. First-order rate constants for GSH turnover were determined for various tissues of Fischer male rats. Animals were administered [ 35 S]Cys by tail vein injection and GSH turnover was estimated by the decrease in GSH specific activity following incorporation of Cys, 1-102 hr after administration. Tissue nonprotein sulfhydryls (NPSH) were detected by Ellman's assay and compared with GSH and Cys concentrations determined by HPLC with electrochemical detection. [ 35 S]GSH was analyzed by HPLC equipped with a flow-through radioactivity detector. Although total GSH and Cys were usually slightly lower than NPSH concentrations for the tissues examined, both assay systems gave comparable results. An exception was the glandular stomach which had approximately 2-fold higher NPSH. Liver and kidney had rapid turnover rates with GSH half-lives between 2-5 hr, while heart and skeletal muscle tissue had half-lives of 80-90 hr. Turnover in the blood was slowest, with a half-life of 170 hr. Gastrointestinal tract tissues were shown to have intermediate turnover rates of the following order: glandular stomach > duodenum = small intestine = caecum = large intestine = colon > forestomach. GSH half-life in lung and skin was approximately 45 hr. These studies indicate that tissues utilize GSH at markedly different rates

  3. Effects of role stress on nurses' turnover intentions: The mediating effects of organizational commitment and burnout.

    Science.gov (United States)

    Han, Sang-Sook; Han, Jeong-Won; An, Young-Suk; Lim, So-Hee

    2015-10-01

    This paper was designed to extend the extant research regarding factors related to nurses' turnover intentions. This survey-based study was based on a path analysis designed to verify a hypothesized causal model involving nurses' role stress, organizational commitment, turnover intentions, and burnout. This study distributed 500 questionnaires to nurses in general hospitals with more than 500 beds located in Seoul, Korea, during 16-30 April 2012. Role conflict, an underlying factor in role stress, had no significant effect on role stress, but the results showed that role ambiguity reduced organizational commitment. On the other hand, role conflict and role ambiguity increased the level of burnout. Organizational commitment reduced turnover intentions, and burnout increased turnover intentions. Role conflict and role ambiguity had no direct effect on turnover intentions, but they had indirect effects on organizational commitment and burnout. To reduce nurses' turnover rate, this study recommends developing plans to improve their organizational commitment because it mediates role stress and turnover intention. © 2014 The Authors. Japan Journal of Nursing Science © 2014 Japan Academy of Nursing Science.

  4. Predicting Employee Turnover from Communication Networks.

    Science.gov (United States)

    Feeley, Thomas H.; Barnett, George A.

    1997-01-01

    Investigates three social network models of employee turnover: a structural equivalence model, a social influence model, and an erosion model. Administers a communication network questionnaire to all 170 employees of an organization. Finds support for all three models of turnover, with the erosion model explaining more of the variance than do the…

  5. Tritium turnover in succulent plants

    International Nuclear Information System (INIS)

    Krishnamoorthy, T.M.; Gogate, S.S.; Soman, S.D.

    1977-01-01

    Measurements of turnover rates for tissue free water tritium (TFWT) and tissue bound tritium (TBT) were carried out in three succulent plants, Opuntia sp., E. Trigona and E. Mili using tritiated water as tracer. The estimated half-times were 52, 57.5 and 80 days for TFWT and 212, 318 and 132 days for TBT in the stems of the above plants respectively. Opuntia sp. showed significant incorporation of TBT, 10% of TFWT on weight basis, while the other two plants showed lesser incorporation, 2-3% of TFWT. However, the leaves of E. Mili indicated the same level of fixation of TBT as the stem of Opuntia sp. (author)

  6. A Ministudy of employee turnover in US hospitals.

    Science.gov (United States)

    Collins, Sandra K; McKinnies, Richard C; Matthews, Eric P; Collins, Kevin S

    2015-01-01

    A ministudy was conducted to collect self-reported employee turnover rates in US hospitals. The results indicate many hospitals are struggling with high employee turnover rates. Widespread variances in ratings were observed across hospitals, which may be due to lack of consistency in how they each calculate their employee turnover. This makes benchmarking for the purposes of performance improvement challenging.

  7. Fatty acid uptake and turnover rate in the ischemic before and after bypass surgery

    International Nuclear Information System (INIS)

    Freundlieb, C.; Hoeck, A.; Vyska, K.; Erbel, R.; Feinendegen, L.E.

    1982-01-01

    17-123-Iodo-heptadecanoic acid (IHA) turnover in myocardium signals myocardial metabolism of free fatty acids. Thus, it appeared promising to examine the influence of cardiovascular surgery on coronary perfusion and on the metabolic state of the ischemic myocardium by use of IHA. The data show that IHA uptake and elimination are two separate parameters which may be changed in the ischemic heart. The two parameters do not necessarily change in parallel. In ischemic heart disease at rest a normal IHA accumulation pattern may be associated with altered regional IHA turnover rates. On the other hand also accumulation defects without changes in IHA turnover rate were observed. Although the relationship between IHA uptake and turnover is not yet sufficiently understood that statements about the indication and prognosis of bypass surgery can be derived

  8. PENGARUH KEPUASAN KERJA DAN KOMITMEN ORGANISASI TERHADAP TURNOVER INTENTION

    Directory of Open Access Journals (Sweden)

    V. Mardi Widyadmono

    2017-04-01

    Full Text Available This study assesses the influence of job satisfaction and organizational commitment on Turnover Intention. Futhermore, the study identify the mediation role of organizational commitment in the relationship between job satifaction and Turnover Intention. The participants of the study are 98 employees working in private companies operated in Yogyakarta, (36 men and 62 women. Respondents complete questionnaire containing questions on job satisfaction variable, questions on organizational commitment and questions on Turnover Intention. The statistics tools applied are regression analysis to assess the relation between variables and Sobel test to measure the mediation role of organizational commitment. The results of the investigation revealed that job satisfication and organizational commitment influence negatively and significantly Turnover Intention. The higher the job satisfication and the organizational commitment of employees lead to the lower Turnover Intention. The organizational commitment does not play mediation role in the relationship between job satisfication and Turnover Intention

  9. Linking HRM Practices and Institutional Setting to Collective Turnover: An Empirical Exploration

    Directory of Open Access Journals (Sweden)

    Dirk Van Dierendonck

    2016-12-01

    Full Text Available The present study addresses the relationship between human resources management (HRM practices and employee turnover by taking into account the influence of socioeconomic environment. Data was collected at company level with an international sample of 830 companies from 12 countries (Netherlands, Belgium, United Kingdom, Brazil, Switzerland, China, France, Italy, Poland, Germany, South Africa, and Spain. A division into four bundles of human resources (HR practices is introduced: remunerative, communication, developmental, and well-being practices. The influence of the socioeconomic environment was factored in by including the institutional setting in terms of the level of coordination as a country-level variable. The results showed that collective turnover is related to both a country’s institutional determinants and to company HR practices. Remunerative HR practices may have a negative influence in terms of enhancing turnover, particularly within countries high in coordination. HR well-being practices are the most beneficial practices in terms of reducing employee turnover. Our study adds to our knowledge on the relation between HR practices and turnover from an international perspective. It complements the empirical knowledge on the effectiveness of HRM practices in a cross-national setting and supports the notion that the institutional context should be given more attention when studying HR effectiveness.

  10. Relationship Between Work-Family Conflict, Job Embeddedness, Workplace Flexibility, and Turnover Intentions

    OpenAIRE

    Afsar, Bilal; Ur Rehman, Zia

    2017-01-01

    The present study seeks to propose and test a research model that investigates job embeddedness as a mediator and workplace flexibility as a moderator of the effect of family-work conflict on turnover intentions. This study uses a survey method and a structured questionnaire to collect data from 187 nurses working in various hospitals in Islamabad, Pakistan. The results showed that on-the-job embeddedness partially mediated the effect of work-family conflict on nurses' turnover intention. Fur...

  11. Explaining turnover intention in Korean public community hospitals: occupational differences.

    Science.gov (United States)

    Hwang, Jee-In; Chang, Hyejung

    2008-01-01

    Personnel in public hospitals had relatively low job satisfaction despite of tenure employment. High turnover rates degrade hospital image and incur additional costs related to recruitment and training. The purposes of this study were to describe the occupational differences and to identify factors affecting turnover intention among public hospital personnel. A questionnaire survey was conducted as part of Administrative Services Quality Evaluation Program by Seoul metropolitan municipality from 1 November to 1 December in 2003. The subjects were 1251 entire hospital personnel in four hospitals. The questionnaire was designed to measure job satisfaction, organizational commitment, turnover intention, and demographic characteristics. Logistic regression analysis was performed to determine factors influencing turnover intention. There were significant differences in job satisfaction, organizational commitment, and turnover intention according to the occupations. The turnover intention rates were highest among physicians, followed by paramedicals and nursing staffs and then administrators. The significant factors affecting turnover intention were involvement and loyalty among physicians, hospital type, satisfaction with systems and loyalty among nursing staffs, satisfaction with relationship and loyalty among administrators, and loyalty among paramedicals. There were different moderators that influence turnover intentions of hospital personnel. Loyalty had the most important effect upon turnover intention in all occupations. 2007 John Wiley & Sons, Ltd

  12. Hypoxic cell turnover in different solid tumor lines

    International Nuclear Information System (INIS)

    Ljungkvist, Anna S.E.; Bussink, Johan; Kaanders, Johannes H.A.M.; Rijken, Paulus F.J.W.; Begg, Adrian C.; Raleigh, James A.; Kogel, Albert J. van der

    2005-01-01

    Purpose: Most solid tumors contain hypoxic cells, and the amount of tumor hypoxia has been shown to have a negative impact on the outcome of radiotherapy. The efficacy of combined modality treatments depends both on the sequence and timing of the treatments. Hypoxic cell turnover in tumors may be important for optimal scheduling of combined modality treatments, especially when hypoxic cell targeting is involved. Methods and Materials: Previously we have shown that a double bioreductive hypoxic marker assay could be used to detect changes of tumor hypoxia in relation to the tumor vasculature after carbogen and hydralazine treatments. This assay was used in the current study to establish the turnover rate of hypoxic cells in three different tumor models. The first hypoxic marker, pimonidazole, was administered at variable times before tumor harvest, and the second hypoxic marker, CCI-103F, was injected at a fixed time before harvest. Hypoxic cell turnover was defined as loss of pimonidazole (first marker) relative to CCI-103F (second marker). Results: The half-life of hypoxic cell turnover was 17 h in the murine C38 colon carcinoma line, 23 h and 49 h in the human xenograft lines MEC82 and SCCNij3, respectively. Within 24 h, loss of pimonidazole-stained areas in C38 and MEC82 occurred concurrent with the appearance of pimonidazole positive cell debris in necrotic regions. In C38 and MEC82, most of the hypoxic cells had disappeared after 48 h, whereas in SCCNij3, viable cells that had been labeled with pimonidazole were still observed after 5 days. Conclusions: The present study demonstrates that the double hypoxia marker assay can be used to study changes in both the proportion of hypoxic tumor cells and their lifespan at the same time. The present study shows that large differences in hypoxic cell turnover rates may exist among tumor lines, with half-lives ranging from 17-49 h

  13. Biochemical markers of bone turnover

    International Nuclear Information System (INIS)

    Kim, Deog Yoon

    1999-01-01

    Biochemical markers of bone turnover has received increasing attention over the past few years, because of the need for sensitivity and specific tool in the clinical investigation of osteoporosis. Bone markers should be unique to bone, reflect changes of bone less, and should be correlated with radiocalcium kinetics, histomorphometry, or changes in bone mass. The markers also should be useful in monitoring treatment efficacy. Although no bone marker has been established to meet all these criteria, currently osteocalcin and pyridinium crosslinks are the most efficient markers to assess the level of bone turnover in the menopausal and senile osteoporosis. Recently, N-terminal telopeptide (NTX), C-terminal telopeptide (CTX) and bone specific alkaline phosphatase are considered as new valid markers of bone turnover. Recent data suggest that CTX and free deoxypyridinoline could predict the subsequent risk of hip fracture of elderly women. Treatment of postmenopausal women with estrogen, calcitonin and bisphosphonates demonstrated rapid decrease of the levels of bone markers that correlated with the long-term increase of bone mass. Factors such as circadian rhythms, diet, age, sex, bone mass and renal function affect the results of biochemical markers and should be appropriately adjusted whenever possible. Each biochemical markers of bone turnover may have its own specific advantages and limitations. Recent advances in research will provide more sensitive and specific assays

  14. Social Capital and Turnover. Towards a Theoretically Informed Model for Social Capital in Turnover Research: Applications to the U.S. Military

    Science.gov (United States)

    2007-03-01

    Hamilton College, Clinton, NY. Porter L. & Steers R. (1973). Organizational, work, and personal factors in employee turnover and absenteeism ...in Modern Sociology. Annual Review of Sociology 24, pp. 1-24. Price, J. (1977). A Theory of Turnover. In Labour turnover and retention (Chapter 3...for measurement. Research Paper, University of Rome La Sapienza, Department of Public Economics: June 2005. Sabatini, F. Social capital, labour

  15. Work hours and turnover intention among hospital physicians in Taiwan: does income matter?

    Science.gov (United States)

    Tsai, Yu-Hsuan; Huang, Nicole; Chien, Li-Yin; Chiang, Jen-Huai; Chiou, Shu-Ti

    2016-11-21

    Physician shortage has become an urgent and critical challenge to many countries. According to the workforce dynamic model, long work hours may be one major pressure point to the attrition of physicians. Financial incentive is a common tool to human power retention. Therefore, this large-scale physician study investigated how pay satisfaction may influence the relationship between work hours and hospital physician's turnover intention. Data were obtained from a nationwide survey of full-time hospital staff members working at 100 hospitals in Taiwan. The analysis sample comprised 2423 full-time physicians. Dependent variable was degree of the physicians' turnover intention to leave the current hospital. The pay satisfaction was assessed by physicians themselves. We employed ordinal logistic regression models to analyze the association between the number of work hours and turnover intention. To consider the cluster effect of hospitals, we used the "gllamm" command in the statistical software package Stata Version 12.1. The results show that 351 (14.5%) of surveyed physicians reported strong intention to leave current hospital. The average work hours per week among hospital physicians was 59.8 h. As expected, work hours exhibited an independent relationship with turnover intention. More importantly, pay satisfaction could not effectively moderate the positive relationship between work hours and intentions to leave current hospital. The findings show that overtime work is prevalent among hospital physicians in Taiwan. Both the Taiwanese government and hospitals must take action to address the emerging problem of physician high turnover rate. Furthermore, hospitals should not consider relying solely on financial incentives to solve the problem. This study encouraged tackling work hour problem, which would lead to the possibility of solving high turnover intention among hospital physicians in Taiwan.

  16. Work hours and turnover intention among hospital physicians in Taiwan: does income matter?

    Directory of Open Access Journals (Sweden)

    Yu-Hsuan Tsai

    2016-11-01

    Full Text Available Abstract Background Physician shortage has become an urgent and critical challenge to many countries. According to the workforce dynamic model, long work hours may be one major pressure point to the attrition of physicians. Financial incentive is a common tool to human power retention. Therefore, this large-scale physician study investigated how pay satisfaction may influence the relationship between work hours and hospital physician’s turnover intention. Methods Data were obtained from a nationwide survey of full-time hospital staff members working at 100 hospitals in Taiwan. The analysis sample comprised 2423 full-time physicians. Dependent variable was degree of the physicians’ turnover intention to leave the current hospital. The pay satisfaction was assessed by physicians themselves. We employed ordinal logistic regression models to analyze the association between the number of work hours and turnover intention. To consider the cluster effect of hospitals, we used the “gllamm” command in the statistical software package Stata Version 12.1. Results The results show that 351 (14.5% of surveyed physicians reported strong intention to leave current hospital. The average work hours per week among hospital physicians was 59.8 h. As expected, work hours exhibited an independent relationship with turnover intention. More importantly, pay satisfaction could not effectively moderate the positive relationship between work hours and intentions to leave current hospital. Conclusions The findings show that overtime work is prevalent among hospital physicians in Taiwan. Both the Taiwanese government and hospitals must take action to address the emerging problem of physician high turnover rate. Furthermore, hospitals should not consider relying solely on financial incentives to solve the problem. This study encouraged tackling work hour problem, which would lead to the possibility of solving high turnover intention among hospital physicians in

  17. Two waves of proteasome-dependent protein degradation in the hippocampus are required for recognition memory consolidation.

    Science.gov (United States)

    Figueiredo, Luciana S; Dornelles, Arethuza S; Petry, Fernanda S; Falavigna, Lucio; Dargél, Vinicius A; Köbe, Luiza M; Aguzzoli, Cristiano; Roesler, Rafael; Schröder, Nadja

    2015-04-01

    Healthy neuronal function and synaptic modification require a concert of synthesis and degradation of proteins. Increasing evidence indicates that protein turnover mediated by proteasome activity is involved in long-term synaptic plasticity and memory. However, its role in different phases of memory remains debated, and previous studies have not examined the possible requirement of protein degradation in recognition memory. Here, we show that the proteasome inhibitor, lactacystin (LAC), infused into the CA1 area of the hippocampus at two specific time points during consolidation, impairs 24-retention of memory for object recognition in rats. Administration of LAC after retrieval did not affect retention. These findings provide the first evidence for a requirement of proteasome activity in recognition memory, indicate that protein degradation in the hippocampus is necessary during selective time windows of memory consolidation, and further our understanding of the role of protein turnover in memory formation. Copyright © 2015 Elsevier Inc. All rights reserved.

  18. Managing teacher turnover

    African Journals Online (AJOL)

    Erna Kinsey

    - ... vacant teaching posts are not filled (Pretorius & Heard, 1999; Anon., ... it reaches critical proportions. This article therefore investigates teacher turnover as a phenome- non to be managed and suggests ways of doing so. The study is based.

  19. [Cost of nursing turnover in a Teaching Hospital].

    Science.gov (United States)

    Ruiz, Paula Buck de Oliveira; Perroca, Marcia Galan; Jericó, Marli de Carvalho

    2016-02-01

    To map the sub processes related to turnover of nursing staff and to investigate and measure the nursing turnover cost. This is a descriptive-exploratory study, classified as case study, conducted in a teaching hospital in the southeastern, Brazil, in the period from May to November 2013. The population was composed by the nursing staff, using Nursing Turnover Cost Calculation Methodology. The total cost of turnover was R$314.605,62, and ranged from R$2.221,42 to R$3.073,23 per employee. The costs of pre-hire totaled R$101.004,60 (32,1%), and the hiring process consumed R$92.743,60 (91.8%) The costs of post-hire totaled R$213.601,02 (67,9%), for the sub process decreased productivity, R$199.982,40 (93.6%). The study identified the importance of managing the cost of staff turnover and the financial impact of the cost of the employee termination, which represented three times the average salary of the nursing staff.

  20. Tracer kinetics: Modelling of tracer behaviour in nonlinear and nonsteady state systems exemplified by the evaluation of protein turnover in plant organs

    International Nuclear Information System (INIS)

    Winkler, E.

    1991-01-01

    If nonlinear biological processes are investigated by means of tracer experiments they can be modelled with linear kinetic equations (compartment equations) as long as the total system is in a stationary state. But if nonstationary behaviour is included considerations on the kinetics of the individual processes are necessary. Within the range of biological and agricultural investigations especially first order reactions (constant fraction processes), zero order reactions (constant amount process) and saturation reactions (Michaelis-Menten-kinetics) are to be taken into account. A rigorous treatment of data based on system theory can be preceeded by graphic-algebraic procedure which may be more or less uncertain in its results but which can easily be handled. An example is given of methodological considerations concerning the combination of evaluation procedures and the discrimination between different reaction mechanisms. It treats protein turnover in 2 different parts of growing wheat plants investigated by means of an 15 N-tracer experiment. Whereas in a stationary system (upper stalk section) linear tracer equations were sufficient irrespective of the true reaction mechanism, for protein synthesis in the upper leaf as a nonstationary system it was necessary to decide between the hypotheses of a zero order and a first order reaction. In accordance with statements in the literature the unambiguous result was a combination of protein synthesis as a zero order process and of protein degradation as a first order process. (orig.) [de

  1. The phase model of burnout and employee turnover.

    Science.gov (United States)

    Goodman, Eric A; Boss, R Wayne

    2002-01-01

    This study explores the phase model of burnout and investigates its relationship to actual turnover in a hospital. The results indicate that employees who turnover have significantly higher burnout phase scores that those who stay in the organization. A further comparison of voluntary and involuntary turnover demonstrates that there is no significant differences on burnout phase scores. The findings lend support to the usefulness of the phase model of burnout.

  2. Human adenosine deaminase: properties and turnover in cultured T and B lymphoblasts

    International Nuclear Information System (INIS)

    Daddona, P.E.

    1981-01-01

    In this study, the properties and rate of turnover of adenosine deaminase are compared in cultured human T and B lymphoblast cell lines. 1) Relative to B lymphoblasts, the level of adenosine deaminase activity in extracts of T lymphoblast cell lines (MOLT-4, RPMI-8402, CCRF-CEM, and CCRF-HSB-2) is elevated 7-14-fold and differs by 2-fold between the C cell lines. 2) In both T and B lymphoblast extracts, the enzyme is apparently identical, based on K/sub m/ for adenosine and deoxyadenosine, K/sub i/ for inosine, V/sub max/ for adenosine, /sub S20,w/, isoelectric pH, and heat stability. Furthermore, by radioimmunoassay, the quantity of adenosine deaminase-immunocreative protein is proportional to the level of enzyme activity in all cell lines studies. 3) Using a purification and selective immunoprecipitation technique, the enzyme turnover could be assessed in cell lines labeled with [ 35 S]methionine. The apparent rate of adenosine deaminase synthesis, relative to total protein, is 2-fold faster in both T cell lines (RPMI-8402 and CCRF-CEM) than in the B cell lines (MGL-8 and GM-130). The apparent half-life (tsub1/2) for the enzyme degradation is 19 and 39 h, respectively, in CCFR-CEM and RPMI-8402, while the tsub1/2 in both B cell lines is 7-9 h. From the net rate of synthesis and degradation, the T cell lines, respectively, exhibit approximately a 6- and 12-fold difference in adenosine deaminase turnover relative to B cells, consistent with the observed differences in enzyme activity. This study suggests that while adenosine deaminase is apparently identical in both T and B lymphoblast cell lines, alterations in both the rate of enzyme synthesis and degradation contribute to its high steady state level in T cells

  3. VALSARTAN REGULATES MYOCARDIAL AUTOPHAGY AND MITOCHONDRIAL TURNOVER IN EXPERIMENTAL HYPERTENSION

    Science.gov (United States)

    Zhang, Xin; Li, Zi-Lun; Crane, John A.; Jordan, Kyra L.; Pawar, Aditya S.; Textor, Stephen C.; Lerman, Amir; Lerman, Lilach O.

    2014-01-01

    Renovascular hypertension alters cardiac structure and function. Autophagy is activated during left ventricular hypertrophy and linked to adverse cardiac function. The Angiotensin II receptor blocker Valsartan lowers blood pressure and is cardioprotective, but whether it modulates autophagy in the myocardium is unclear. We hypothesized that Valsartan would alleviate autophagy and improve left ventricular myocardial mitochondrial turnover in swine renovascular hypertension. Domestic pigs were randomized to control, unilateral renovascular hypertension, and renovascular hypertension treated with Valsartan (320 mg/day) or conventional triple therapy (Reserpine+hydralazine+hydrochlorothiazide) for 4 weeks post 6-weeks of renovascular hypertension (n=7 each group). Left ventricular remodeling, function and myocardial oxygenation and microcirculation were assessed by multi-detector computer tomography, blood-oxygen-level-dependent magnetic resonance imaging and microcomputer tomography. Myocardial autophagy, markers for mitochondrial degradation and biogenesis, and mitochondrial respiratory-chain proteins were examined ex vivo. Renovascular hypertension induced left ventricular hypertrophy and myocardial hypoxia, enhanced cellular autophagy and mitochondrial degradation, and suppressed mitochondrial biogenesis. Valsartan and triple therapy similarly decreased blood pressure, but Valsartan solely alleviated left ventricular hypertrophy, ameliorated myocardial autophagy and mitophagy, and increased mitochondrial biogenesis. In contrast, triple therapy only slightly attenuated autophagy and preserved mitochondrial proteins, but elicited no improvement in mitophagy. These data suggest a novel potential role of Valsartan in modulating myocardial autophagy and mitochondrial turnover in renovascular hypertension-induced hypertensive heart disease, which may possibly bolster cardiac repair via a blood pressure-independent manner. PMID:24752430

  4. 41 CFR 109-27.5002 - Stores inventory turnover ratio.

    Science.gov (United States)

    2010-07-01

    ... turnover ratio. 109-27.5002 Section 109-27.5002 Public Contracts and Property Management Federal Property....5002 Stores inventory turnover ratio. Comparison of investment in stores inventories to annual issues... comparison may be expressed either as a turnover ratio (dollar value of issues divided by dollar value of...

  5. Employee Turnover: An Empirical and Methodological Assessment.

    Science.gov (United States)

    Muchinsky, Paul M.; Tuttle, Mark L.

    1979-01-01

    Reviews research on the prediction of employee turnover. Groups predictor variables into five general categories: attitudinal (job satisfaction), biodata, work-related, personal, and test-score predictors. Consistent relationships between common predictor variables and turnover were found for four categories. Eight methodological problems/issues…

  6. Causes and consequences of collective turnover: a meta-analytic review.

    Science.gov (United States)

    Heavey, Angela L; Holwerda, Jacob A; Hausknecht, John P

    2013-05-01

    Given growing interest in collective turnover (i.e., employee turnover at unit and organizational levels), the authors propose an organizing framework for its antecedents and consequences and test it using meta-analysis. Based on analysis of 694 effect sizes drawn from 82 studies, results generally support expected relationships across the 6 categories of collective turnover antecedents, with somewhat stronger and more consistent results for 2 categories: human resource management inducements/investments and job embeddedness signals. Turnover was negatively related to numerous performance outcomes, more strongly so for proximal rather than distal outcomes. Several theoretically grounded moderators help to explain average effect-size heterogeneity for both antecedents and consequences of turnover. Relationships generally did not vary according to turnover type (e.g., total or voluntary), although the relative absence of collective-level involuntary turnover studies is noted and remains an important avenue for future research. PsycINFO Database Record (c) 2013 APA, all rights reserved.

  7. Turnover intention of graduate nurses in South Korea.

    Science.gov (United States)

    Lee, Haejung; Lim, Yeonjung; Jung, Hee Young; Shin, Youn-Wha

    2012-06-01

    The purpose of this study was to identify the turnover intention of graduate nurses in South Korea and to explore the correlates of turnover intention. A descriptive, correlational design was used. The participants comprised 225 female nurses who were working at 13 general hospitals and who had accumulated turnover intention was 7.51. Turnover intention was found to be related to the number of beds in the hospital, workplace, and duration of job orientation (theory and practice), instruction by a preceptor, job stress, clinical competence, self-efficacy, and the practice environment. In the multivariate approach, the practice environment, job stress, and the workplace were found to be significantly related to turnover intention and accounted for 36% of the said intention in the studied graduate nurses. The results support that the characteristics of magnet hospitals that improve the practice environment could play a critical role in retaining nurses in hospitals. Managerial interventions that enhance the practice environment, reduce job stress, and place graduate nurses in nursing units with a single specialty could benefit the hospitals employing such nurses. Further research to explore the effects of managerial strategies on graduate nurses' turnover intention is warranted. © 2011 The Authors; Japan Journal of Nursing Science © 2011 Japan Academy of Nursing Science.

  8. The efficiency of a dedicated staff on operating room turnover time in hand surgery.

    Science.gov (United States)

    Avery, Daniel M; Matullo, Kristofer S

    2014-01-01

    To evaluate the effect of orthopedic and nonorthopedic operating room (OR) staff on the efficiency of turnover time in a hand surgery practice. A total of 621 sequential hand surgery cases were retrospectively reviewed. Turnover times for sequential cases were calculated and analyzed with regard to the characteristics of the OR staff being primarily orthopedic or nonorthopedic. A total of 227 turnover times were analyzed. The average turnover time with all nonorthopedic staff was 31 minutes, for having only an orthopedic surgical technician was 32 minutes, for having only an orthopedic circulator was 25 minutes, and for having both an orthopedic surgical technician and a circulator was 20 minutes. Statistical significance was seen when comparing only an orthopedic surgical technician versus both an orthopedic circulator and a surgical technician and when comparing both nonorthopedic staff versus both an orthopedic circulator and a surgical technician. OR efficiency is being increasingly evaluated for its effect on hospital revenue and OR staff costs. Reducing turnover time is one aspect of a multifaceted solution in increasing efficiency. Our study showed that, for hand surgery, orthopedic-specific staff can reduce turnover time. Economic/Decision Analysis III. Copyright © 2014 American Society for Surgery of the Hand. Published by Elsevier Inc. All rights reserved.

  9. Salary and Ranking and Teacher Turnover: A Statewide Study

    Science.gov (United States)

    Garcia, Cynthia Martinez; Slate, John R.; Delgado, Carmen Tejeda

    2009-01-01

    This study examined three years of data obtained from the Academic Excellence Indicator System of the State of Texas regarding teacher turnover rate and teacher salary. Across all public school districts, teacher salary was consistently negatively related to teacher turnover; that is, where salary was lower, turnover rate was higher When data were…

  10. Stochastic lattice model of synaptic membrane protein domains.

    Science.gov (United States)

    Li, Yiwei; Kahraman, Osman; Haselwandter, Christoph A

    2017-05-01

    Neurotransmitter receptor molecules, concentrated in synaptic membrane domains along with scaffolds and other kinds of proteins, are crucial for signal transmission across chemical synapses. In common with other membrane protein domains, synaptic domains are characterized by low protein copy numbers and protein crowding, with rapid stochastic turnover of individual molecules. We study here in detail a stochastic lattice model of the receptor-scaffold reaction-diffusion dynamics at synaptic domains that was found previously to capture, at the mean-field level, the self-assembly, stability, and characteristic size of synaptic domains observed in experiments. We show that our stochastic lattice model yields quantitative agreement with mean-field models of nonlinear diffusion in crowded membranes. Through a combination of analytic and numerical solutions of the master equation governing the reaction dynamics at synaptic domains, together with kinetic Monte Carlo simulations, we find substantial discrepancies between mean-field and stochastic models for the reaction dynamics at synaptic domains. Based on the reaction and diffusion properties of synaptic receptors and scaffolds suggested by previous experiments and mean-field calculations, we show that the stochastic reaction-diffusion dynamics of synaptic receptors and scaffolds provide a simple physical mechanism for collective fluctuations in synaptic domains, the molecular turnover observed at synaptic domains, key features of the observed single-molecule trajectories, and spatial heterogeneity in the effective rates at which receptors and scaffolds are recycled at the cell membrane. Our work sheds light on the physical mechanisms and principles linking the collective properties of membrane protein domains to the stochastic dynamics that rule their molecular components.

  11. Substance Abuse-Specific Knowledge Transfer or Loss? Treatment Program Turnover versus Professional Turnover among Substance Abuse Clinicians

    Science.gov (United States)

    Eby, Lillian T.; Curtis, Sara L.

    2014-01-01

    This longitudinal study investigated the extent to which substance abuse (SA) clinician turnover is associated with SA-specific knowledge loss due to change in professions (professional turnover) versus SA-specific knowledge transfer due to movement from one SA clinical setting to another (treatment program turnover). For this study, clinicians had to voluntarily leave their current treatment program. Eligible clinicians completed a quantitative survey while employed and a qualitative post-employment exit interview 1 year later. Compared to those that exited the SA profession (N = 99), clinicians who changed treatment programs (N = 120) had greater SA-specific formal knowledge and were more likely to be personally in recovery. No differences were found between the two groups in terms of SA-specific practical knowledge. PMID:25115318

  12. HUBUNGAN ANTARA KETERLIBATAN KERJA DENGAN TURNOVER INTENTION PADA KARYAWAN PT. GARDA TRIMITRA UTAMA, JAKARTA

    Directory of Open Access Journals (Sweden)

    Roni Faslah

    2010-08-01

    Full Text Available The purpose of this research is to get a valid and reliable data or fact, to know the correlations between job involvement with turnover intention to employee PT. Garda Trimitra Utama, Jakarta.The analysis test by finding regression equation, that is Ŷ = 75,304 – 0,238X. For regression significance test and the result is, F-count (5,94 > F-table (4,03. Showing that, it has significance regression. While regression linearity test, F-count (1,54 < F-table = (1.96, showing that regression is linear. The result of product moment of correlations coefficient test, is rxy = -0,231 continued by using correlations coefficient significance test with t-test. Counting result is, t-count(-1,73 < -t-table (-1,67. It means that there are significance and negative correlations between job involvement with turnover intention.Beside that, the result of determination coefficient test is 5,34%, it means that turnover intention to employee variable determined by 5,34% job involvement variable. The conclusion of the research have shown that there is a negative correlations between job involvement with turnover intention to employee.

  13. Retaining the nursing workforce: factors contributing to the reduction of nurses' turnover intention in Japan.

    Science.gov (United States)

    Takase, Miyuki; Teraoka, Sachiko; Yabase, Kousuke

    2016-01-01

    The aim of this study was to investigate the effects of psychological contract fulfilment, perceived advancement opportunities and age on reducing the turnover intention of nurses in Japan. The factors that contribute to and mitigate the intentions of nurses to leave their organisations need to be investigated to understand the determinants of nurse turnover better. However, there is a paucity of studies identifying these mitigating factors. Potential participants were 1337 registered nurses and midwives, of whom 766 participated in the study (a return rate of 57%). The data were analysed using a moderated regression analysis. Fulfilment of the psychological contract and perceived advancement opportunities independently and jointly contributed to a reduction in nurses' turnover intentions. The results also showed that nurses' ages were negatively correlated with their turnover intentions. Fulfilment of the psychological contract and advancement opportunities are important for reducing nurses' turnover intentions, especially among younger nurses. Clear guidelines/evaluations of contributions made by nurses and their organisations are needed to enhance the experience of nurses in terms of psychological contract fulfilment. Moreover, a structured advancement support system needs to be implemented to reduce nurses' turnover intentions. © 2014 John Wiley & Sons Ltd.

  14. Stock Option Compensation and Managerial Turnover

    OpenAIRE

    Raluca Georgiana NASTASESCU

    2009-01-01

    This study examines the association between managerial turnover and equity-based compensation. I investigate whether stock options act to bond executives to their firms and whether retention of managers is a motivation of companies in designing CEO incentive contracts. The results show that stock options do negatively influence the probability of a CEO leaving the company. The monetary cost of losing the value of equity-based compensation package keeps the manager with his company. I also fin...

  15. Unit-level voluntary turnover rates and customer service quality: implications of group cohesiveness, newcomer concentration, and size.

    Science.gov (United States)

    Hausknecht, John P; Trevor, Charlie O; Howard, Michael J

    2009-07-01

    Despite substantial growth in the service industry and emerging work on turnover consequences, little research examines how unit-level turnover rates affect essential customer-related outcomes. The authors propose an operational disruption framework to explain why voluntary turnover impairs customers' service quality perceptions. On the basis of a sample of 75 work units and data from 5,631 employee surveys, 59,602 customer surveys, and organizational records, results indicate that unit-level voluntary turnover rates are negatively related to service quality perceptions. The authors also examine potential boundary conditions related to the disruption framework. Of 3 moderators studied (group cohesiveness, group size, and newcomer concentration), results show that turnover's negative effects on service quality are more pronounced in larger units and in those with a greater concentration of newcomers.

  16. Autoradiographic imaging of phosphoinositide turnover in the brain

    International Nuclear Information System (INIS)

    Hwang, P.M.; Bredt, D.S.; Snyder, S.H.

    1990-01-01

    With [ 3 H]cytidine as a precursor, phosphoinositide turnover can be localized in brain slices by selective autoradiography of the product [ 3 H]cytidine diphosphate diacylglycerol, which is membrane-bound. In the cerebellum, glutamatergic stimulation elicits an increase of phosphoinositide turnover only in Purkinje cells and the molecular layer. In the hippocampus, both glutamatergic and muscarinic cholinergic stimulation increase phosphoinositide turnover, but with distinct localizations. Cholinergic stimulation affects CA1, CA3, CA4, and subiculum, whereas glutamatergic effects are restricted to the subiculum and CA3. Imaging phosphoinositide turnover in brain slices, which are amenable to electrophysiologic studies, will permit a dynamic localized analysis of regulation of this second messenger in response to synaptic stimulation of specific neuronal pathways

  17. Substance use disorder counselors' job performance and turnover after 1 year: linear or curvilinear relationship?

    Science.gov (United States)

    Laschober, Tanja C; de Tormes Eby, Lillian Turner

    2013-07-01

    The main goals of the current study were to investigate whether there are linear or curvilinear relationships between substance use disorder counselors' job performance and actual turnover after 1 year utilizing four indicators of job performance and three turnover statuses (voluntary, involuntary, and no turnover as the reference group). Using longitudinal data from 440 matched counselor-clinical supervisor dyads, results indicate that overall, counselors with lower job performance are more likely to turn over voluntarily and involuntarily than not to turn over. Further, one of the job performance measures shows a significant curvilinear effect. We conclude that the negative consequences often assumed to be "caused" by counselor turnover may be overstated because those who leave both voluntarily and involuntarily demonstrate generally lower performance than those who remain employed at their treatment program.

  18. Direct and Indirect Effects of Psychological Contract Breach on Academicians’ Turnover Intention in Turkey

    OpenAIRE

    Buyukyilmaz, Ozan; Cakmak, Ahmet F.

    2013-01-01

    This study aims to investigate the assumed direct and indirect relationships between psychological contract breach and turnover intention through psychological contract violation and perceived organizational support. Data for the sample was collected from 570 academicians from a variety of universities in Turkey. Hierarchical regression analyses were conducted to test the hypotheses. The results show that psychological contract breach was positively related to turnover intention and psycholog...

  19. Histone H4 hyperacetylation and rapid turnover of its acetyl groups in transcriptionally inactive rooster testis spermatids.

    Science.gov (United States)

    Oliva, R; Mezquita, C

    1982-01-01

    In order to study the relationship between acetylation of histones, chromatin structure and gene activity, the distribution and turnover of acetyl groups among nucleosomal core histones and the extent of histone H4 acetylation were examined in rooster testis cell nuclei at different stages of spermatogenesis. Histone H4 was the predominant acetylated histone in mature testes. Hyperacetylation of H4 and rapid turnover of its acetyl groups are not univocally correlated with transcriptional activity since they were detected in both genetically active testicular cells and genetically inactive elongated spermatids. During the transition from nucleohistone to nucleoprotamine in elongated spermatids the chromatin undergoes dramatic structural changes with exposition of binding sites on DNA (1). Hyperacetylation of H4 and rapid turnover of its acetyl groups could be correlated with the particular conformation of chromatin in elongated spermatids and might represent a necessary condition for binding of chromosomal proteins to DNA. Images PMID:7162988

  20. Physician and staff turnover in community primary care practice.

    Science.gov (United States)

    Ruhe, Mary; Gotler, Robin S; Goodwin, Meredith A; Stange, Kurt C

    2004-01-01

    The effect of a rapidly changing healthcare system on personnel turnover in community family practices has not been analyzed. We describe physician and staff turnover and examine its association with practice characteristics and patient outcomes. A cross-sectional evaluation of length of employment of 150 physicians and 762 staff in 77 community family practices in northeast Ohio was conducted. Research nurses collected data using practice genograms, key informant interviews, staff lists, practice environment checklists, medical record reviews, and patient questionnaires. The association of physician and staff turnover with practice characteristics, patient satisfaction, and preventive service data was tested. During a 2-year period, practices averaged a 53% turnover rate of staff. The mean length of duration of work at the current practice location was 9.1 years for physicians and 4.1 years for staff. Longevity varied by position, with a mean of 3.4 years for business employees, 4.0 years for clinical employees, and 7.8 years for office managers. Network-affiliated practices experienced higher turnover than did independent practices. Physician longevity was associated with a practice focus on managing chronic illness, keeping on schedule, and responding to insurers' requests. No association was found between turnover and patient satisfaction or preventive service delivery rates. Personnel turnover is pervasive in community primary care practices and is associated with employee role, practice network affiliation, and practice focus. The potentially disruptive effect of personnel turnover on practice functioning, finances, and longitudinal relationships with patients deserves further study despite the reassuring lack of association with patient satisfaction and preventive service delivery rates.

  1. University Lecturers' Professional Empowerment and Turnover in ...

    African Journals Online (AJOL)

    Many universities in Uganda are grappling with the challenge of academic staff turnover. While research conducted so far has established different factors explaining the problems of turnover, many of which have been addressed, this challenge has not been resolved. Hitherto, attention has not been paid to whether ...

  2. Relationship between Job Satisfaction and Turnover Intention ...

    African Journals Online (AJOL)

    This study explores the association between job satisfaction and turnover intentions among lecturers in three public universities in Tanzania. It had three objectives: (1) to determine the level of perceived job satisfaction among lecturers; (2) to determine the association between job satisfaction and turnover intention; and (3) ...

  3. Increased soluble serum markers caspase-cleaved cytokeratin-18, histones, and ST2 indicate apoptotic turnover and chronic immune response in COPD.

    Science.gov (United States)

    Hacker, Stefan; Lambers, Christopher; Pollreisz, Andreas; Hoetzenecker, Konrad; Lichtenauer, Michael; Mangold, Andreas; Niederpold, Tina; Hacker, Andreas; Lang, György; Dworschak, Martin; Vukovich, Thomas; Gerner, Christopher; Klepetko, Walter; Ankersmit, Hendrik Jan

    2009-01-01

    Chronic obstructive pulmonary disease (COPD) is a worldwide burden and a major cause of death. The disease is accompanied by chronic inflammation and increased cellular turnover that is partly due to an overwhelming induction of apoptosis. In this study, we hypothesized that systemic markers of apoptosis are altered in patients with mild-to-severe COPD. A total number of 64 patients and controls were enrolled in the study. Lung function parameters of all groups (nonsmoker, healthy smoker, COPD GOLD I&II, COPD GOLD III&IV) were evaluated at the time of inclusion. Enzyme-linked immunosorbent assays were used to quantify protein levels in serum samples. Serum contents of apoptotic end-products caspase-cleaved cytokeratin-18 and histone-associated-DNA-fragments were increased in patients with COPD, whereas anti-inflammatory soluble ST2 showed a peak in patients with COPD I&II (P=0.031) compared to healthy smokers. Levels of pro-inflammatory caspase-1/ ICE correlated significantly with the number of pack years (R=0.337; P=0.007). Our results indicate a systemic release of apoptosis-specific proteins as markers for increased cellular turnover accompanied by progression of COPD. Furthermore, soluble ST2 seems to have a critical role in the anti-inflammatory regulatory mechanism at early stages of the disease.

  4. Protein kinase C, focal adhesions and the regulation of cell migration

    DEFF Research Database (Denmark)

    Fogh, Betina S; Multhaupt, Hinke A B; Couchman, John Robert

    2014-01-01

    in their intracellular compartment. Among these are tyrosine kinases, which have received a great deal of attention, whereas the serine/threonine kinase protein kinase C has received much less. Here the status of protein kinase C in focal adhesions and cell migration is reviewed, together with discussion of its roles...... and adhesion turnover. Focal adhesions, or focal contacts, are widespread organelles at the cell-matrix interface. They arise as a result of receptor interactions with matrix ligands, together with clustering. Recent analysis shows that focal adhesions contain a very large number of protein components...

  5. One hundred years of employee turnover theory and research.

    Science.gov (United States)

    Hom, Peter W; Lee, Thomas W; Shaw, Jason D; Hausknecht, John P

    2017-03-01

    We review seminal publications on employee turnover during the 100-year existence of the Journal of Applied Psychology . Along with classic articles from this journal, we expand our review to include other publications that yielded key theoretical and methodological contributions to the turnover literature. We first describe how the earliest papers examined practical methods for turnover reduction or control and then explain how theory development and testing began in the mid-20th century and dominated the academic literature until the turn of the century. We then track 21st century interest in the psychology of staying (rather than leaving) and attitudinal trajectories in predicting turnover. Finally, we discuss the rising scholarship on collective turnover given the centrality of human capital flight to practitioners and to the field of human resource management strategy. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

  6. Exploring correlates of turnover among nursing assistants in the National Nursing Home Survey.

    Science.gov (United States)

    Temple, April; Dobbs, Debra; Andel, Ross

    2011-01-01

    High turnover of nursing assistants (NAs) has implications for the quality of nursing home care. Greater understanding of correlates of NA turnover is needed to provide insight into possible retention strategies. This study examined nursing home organizational characteristics and specific job characteristics of staff in relation to turnover of NAs. Cross-sectional data on 944 nationally representative nursing homes were derived from the 2004 National Nursing Home Survey. Using a 3-month turnover rate, 25% of the facilities with the lowest turnover rates were classified as low turnover, 25% of the facilities with the highest turnover were classified as high turnover, and the remaining 50% of the facilities were classified as moderate turnover. Multinomial logistic regression was used to examine organizational and job characteristics associated with low and high turnover compared with moderate turnover. One organizational characteristic, staffing levels at or greater than 4.0 hours per patient day, was associated with greater odds of low NA turnover and reduced odds of high NA turnover. Job characteristics including higher wages and union membership were associated with greater odds of low NA turnover, whereas wages, fully paid health insurance, employee assistance benefits, and involvement in resident care planning were associated with reduced odds of high NA turnover. The results of this study suggest that job characteristics of NA staff may be particularly important for turnover. Specifically, the provision of competitive wages and benefits (particularly health insurance) and involvement of NAs in resident care planning could potentially reduce NA turnover, as could maintaining high levels of nurse staffing.

  7. The Structural Model of Psychological Contract Violation, Organizational Commitment, Turnover, Job Satisfaction and Deviant Behaviors

    Directory of Open Access Journals (Sweden)

    M. Golparvar

    2014-12-01

    Full Text Available This research was conducted with the purpose of studying the structural model of the relationships of psychological contract violation with organizational commitment, turnover, job satisfaction and deviant behaviors. Research method was correlation and the statistical population were male employees of an industrial company in Shiraz city, from among which 300 employees were selected using convenience sampling. Assessment instruments consisted of Psychological Contract Violation Questionnaire (Tekleab etal, 2005, Organizational Commitment Questionnaire (Speier & Vankatesh, 2002, Job Satisfaction Questionnaire (Spector, 1985, Turnover Questionnaire (Tekleab etal, 2005 and Deviant Behavior Questionnaire (Bennett & Robinson, 2000. Data was analyzed using Pearson’s correlation coefficient, structure equation modeling (SEM and mediation analysis. Findings showed that psychological contract violation explained 7.1 percent of organizational commitment variance, organizational commitment and job satisfaction explained 16.7 percent of turnover variance, organizational commitment explained 20.3 percent of job satisfaction variance and turnover explained 4.3 percent of deviant behavior variance. Mediation analysis showed that organizational commitment played the complete mediator variable in the relation of psychological contract violation with job satisfaction and job satisfaction was the partial mediator variable in the relation of organizational commitment with turnover. Finally with regard to the limitation of generalization of current research results it is suggested to industrial organizations that they should not violate their obligations to employees in anyway.

  8. Job turnover and labor turnover : a taxonomy of employment dynamics

    NARCIS (Netherlands)

    Hassink, Wolter H.J.; Hamermesh, Daniel S.

    1994-01-01

    We present an organized set of stylized facts on the relations among flows of workers,changes in employment and changes in the numer of jobs at the firm level. Job turnover isusually measured by comparing stocks of employment in each firm at two points in time andadding up the absolute employment

  9. Long-term nitrogen addition affects the phylogenetic turnover of soil microbial community responding to moisture pulse.

    Science.gov (United States)

    Liu, Chi; Yao, Minjie; Stegen, James C; Rui, Junpeng; Li, Jiabao; Li, Xiangzhen

    2017-12-13

    How press disturbance (long-term) influences the phylogenetic turnover of soil microbial communities responding to pulse disturbances (short-term) is not fully known. Understanding the complex connections between the history of environmental conditions, assembly processes and microbial community dynamics is necessary to predict microbial response to perturbation. We started by investigating phylogenetic spatial turnover (based on DNA) of soil prokaryotic communities after long-term nitrogen (N) deposition and temporal turnover (based on RNA) of communities responding to pulse by conducting short-term rewetting experiments. The results showed that moderate N addition increased ecological stochasticity and phylogenetic diversity. In contrast, high N addition slightly increased homogeneous selection and decreased phylogenetic diversity. Examining the system with higher phylogenetic resolution revealed a moderate contribution of variable selection across the whole N gradient. The moisture pulse experiment showed that high N soils had higher rates of phylogenetic turnover across short phylogenetic distances and significant changes in community compositions through time. Long-term N input history influenced spatial turnover of microbial communities, but the dominant community assembly mechanisms differed across different N deposition gradients. We further revealed an interaction between press and pulse disturbances whereby deterministic processes were particularly important following pulse disturbances in high N soils.

  10. Effects of Nurses' Perceptions of Actual and Demanded Competence on Turnover Intentions.

    Science.gov (United States)

    Takase, Miyuki; Yamamoto, Masako; Sato, Yoko; Imai, Takiko; Kawamoto, Mitsuko

    2017-10-01

    With the growing focus on continuous professional development, demands placed on nurses to uphold nursing competence have been increasing. This study examined how nurses with different lengths of clinical experience perceived the relationship between their actual competence and the competence they felt was demanded of them, and how this relationship was related to their turnover intentions. Survey questionnaires were distributed to 1,377 nurses, of whom 765 returned usable completed forms. The results showed that across all the groups of clinical experience, nurses perceived the demanded competence levels to be higher than their actual competence levels. However, turnover intentions were not related to nurses' perceptions of demanded competence and were negatively related to perceptions of actual competence. The levels of competence demanded should not be considered as threats for nurses. Improving nurses' competence may reduce their turnover intentions.

  11. Plant traits and environment: floating leaf blade production and turnover of waterlilies.

    Science.gov (United States)

    Klok, Peter F; van der Velde, Gerard

    2017-01-01

    Floating leaf blades of waterlilies fulfill several functions in wetland ecosystems by production, decomposition and turnover as well as exchange processes. Production and turnover rates of floating leaf blades of three waterlily species, Nuphar lutea (L.) Sm., Nymphaea alba L. and Nymphaea candida Presl, were studied in three freshwater bodies, differing in trophic status, pH and alkalinity. Length and percentages of leaf loss of marked leaf blades were measured weekly during the growing season. Area and biomass were calculated based on leaf length and were used to calculate the turnover rate of floating leaf blades. Seasonal changes in floating leaf production showed that values decreased in the order: Nymphaea alba , Nuphar lutea , Nymphaea candida . The highest production was reached for Nuphar lutea and Nymphaea alba in alkaline, eutrophic water bodies. The production per leaf was relatively high for both species in the acid water body. Nymphaea candida showed a very short vegetation period and low turnover rates. The ratio Total potential leaf biomass/Maximum potential leaf biomass (P/B max ) of the three species ranged from 1.35-2.25. The ratio Vegetation period (Period with floating leaves)/Mean leaf life span ranged from 2.94-4.63, the ratio Growth period (Period with appearance of new floating leaves)/Vegetation period from 0.53-0.73. The clear differences between Nymphaea candida versus Nuphar lutea and Nymphaea alba , may be due to adaptations of Nymphaea candida to an Euro-Siberic climate with short-lasting summer conditions.

  12. Nurse turnover in the Kingdom of Saudi Arabia: An integrative review.

    Science.gov (United States)

    Falatah, Rawaih; Salem, Olfat A

    2018-04-06

    To appraise and synthesise existing literature on nurse turnover in the Saudi Arabian context. Saudi Arabia is notably one of the nations with a health care system that is bombarded by high rates of turnover and turnover intention. Moreover, rapid population growth and the expansion of the health care system increase the demand on registered nurses in the kingdom. Eleven primary sources were reviewed using Whittemore and Knafl's (Journal of Advanced Nursing, 2005; 52, 546-553) integrative review method. There is variation in the reported turnover rates across the studies. The identified determinants of nurse turnover in the Saudi Arabian context included nurses' demographics, satisfaction, leadership and management, and job-related factors. There is a need for more studies that focus on the cost and outcome of nurse turnover and turnover intention in the Saudi Arabian context. The review highlights the alarming rates of nurse turnover and its determinants in Saudi Arabia. Nurse managers in Saudi Arabia should consider this information, as they make daily assignments. © 2018 John Wiley & Sons Ltd.

  13. Patient-centered medical home implementation and primary care provider turnover.

    Science.gov (United States)

    Sylling, Philip W; Wong, Edwin S; Liu, Chuan-Fen; Hernandez, Susan E; Batten, Adam J; Helfrich, Christian D; Nelson, Karin; Fihn, Stephan D; Hebert, Paul L

    2014-12-01

    The Veterans Health Administration (VHA) began implementing a patient-centered medical home (PCMH) model of care delivery in April 2010 through its Patient Aligned Care Team (PACT) initiative. PACT represents a substantial system reengineering of VHA primary care and its potential effect on primary care provider (PCP) turnover is an important but unexplored relationship. This study examined the association between a system-wide PCMH implementation and PCP turnover. This was a retrospective, longitudinal study of VHA-employed PCPs spanning 29 calendar quarters before PACT and eight quarters of PACT implementation. PCP employment periods were identified from administrative data and turnover was defined by an indicator on the last quarter of each uncensored period. An interrupted time series model was used to estimate the association between PACT and turnover, adjusting for secular trend and seasonality, provider and job characteristics, and local unemployment. We calculated average marginal effects (AME), which reflected the change in turnover probability associated with PACT implementation. The quarterly rate of PCP turnover was 3.06% before PACT and 3.38% after initiation of PACT. In adjusted analysis, PACT was associated with a modest increase in turnover (AME=4.0 additional PCPs per 1000 PCPs per quarter, P=0.004). Models with interaction terms suggested that the PACT-related change in turnover was increasing in provider age and experience. PACT was associated with a modest increase in PCP turnover, concentrated among older and more experienced providers, during initial implementation. Our findings suggest that policymakers should evaluate potential workforce effects when implementing PCMH.

  14. The tear turnover and tear clearance tests - a review.

    Science.gov (United States)

    Garaszczuk, Izabela K; Montes Mico, Robert; Iskander, D Robert; Expósito, Alejandro Cerviño

    2018-03-01

    The aim is to provide a summary of methods available for the assessment of tear turnover and tear clearance rates. The review defines tear clearance and tear turnover and describes their implication for ocular surface health. Additionally, it describes main types of techniques for measuring tear turnover, including fluorescein tear clearance tests, techniques utilizing electromagnetic spectrum and tracer molecule and novel experimental techniques utilizing optical coherence tomography and fluorescein profilometry. Areas covered: Internet databases (PubMed, Science Direct, Google Scholar) and most frequently cited references were used as a principal resource of information on tear turnover rate and tear clearance rate, presenting methodologies and equipment, as well as their definition and implications for the anterior eye surface health and function. Keywords used for data-search were as follows: tear turnover, tear clearance, fluorescein clearance, scintigraphy, fluorophotometry, tear flow, drainage, tear meniscus dynamics, Krehbiel flow and lacrimal functional unit. Expert commentary: After decades, the topic of tear turnover assessment has been reintroduced. Recently, new techniques have been developed to propose less invasive, less time consuming and simpler methodologies for the assessment of tear dynamics that have the potential to be utilized in clinical practice.

  15. Stable isotopic constraints on global soil organic carbon turnover

    Science.gov (United States)

    Wang, Chao; Houlton, Benjamin Z.; Liu, Dongwei; Hou, Jianfeng; Cheng, Weixin; Bai, Edith

    2018-02-01

    Carbon dioxide release during soil organic carbon (SOC) turnover is a pivotal component of atmospheric CO2 concentrations and global climate change. However, reliably measuring SOC turnover rates on large spatial and temporal scales remains challenging. Here we use a natural carbon isotope approach, defined as beta (β), which was quantified from the δ13C of vegetation and soil reported in the literature (176 separate soil profiles), to examine large-scale controls of climate, soil physical properties and nutrients over patterns of SOC turnover across terrestrial biomes worldwide. We report a significant relationship between β and calculated soil C turnover rates (k), which were estimated by dividing soil heterotrophic respiration rates by SOC pools. ln( - β) exhibits a significant linear relationship with mean annual temperature, but a more complex polynomial relationship with mean annual precipitation, implying strong-feedbacks of SOC turnover to climate changes. Soil nitrogen (N) and clay content correlate strongly and positively with ln( - β), revealing the additional influence of nutrients and physical soil properties on SOC decomposition rates. Furthermore, a strong (R2 = 0.76; p turnover and thereby improving predictions of multiple global change influences over terrestrial C-climate feedback.

  16. Changes in Inflammatory and Bone Turnover Markers After Periodontal Disease Treatment in Patients With Diabetes.

    Science.gov (United States)

    Izuora, Kenneth E; Ezeanolue, Echezona E; Neubauer, Michael F; Gewelber, Civon L; Allenback, Gayle L; Shan, Guogen; Umpierrez, Guillermo E

    2016-06-01

    The underlying mechanisms for increased osteopenia and fracture rates in patients with diabetes are not well understood, but may relate to chronic systemic inflammation. We assessed the effect of treating periodontal disease (POD), a cause of chronic inflammation, on inflammatory and bone turnover markers in patients with diabetes. Using an investigator-administered questionnaire, we screened a cross-section of patients presenting for routine outpatient diabetes care. We recruited 22 subjects with POD. Inflammatory and bone turnover markers were measured at baseline and 3 months following POD treatment (scaling, root planing and subantimicrobial dose doxycycline). There were nonsignificant reductions in high-sensitivity C-reactive protein (6.34-5.52mg/L, P = 0.626) and tumor necrosis factor-alpha (10.37-10.01pg/mL, P = 0.617). There were nonsignificant increases in urinary C-terminal telopeptide (85.50-90.23pg/mL, P = 0.684) and bone-specific alkaline phosphatase (7.45-8.79pg/mL, P = 0.074). Patients with >90% adherence with doxycycline were 6.4 times more likely to experience reduction in tumor necrosis factor-alpha (P = 0.021) and 2.8 times more likely to experience reductions in high-sensitivity C-reactive protein (P = 0.133). Treatment of POD in patients with diabetes resulted in nonsignificant lowering of inflammatory markers and nonsignificant increase in bone turnover markers. However, adherence to doxycycline therapy resulted in better treatment effects. Copyright © 2016 Southern Society for Clinical Investigation. Published by Elsevier Inc. All rights reserved.

  17. Employee Turnover: Evidence from a Case Study.

    Science.gov (United States)

    Borland, Jeff

    1997-01-01

    Patterns of employee turnover from a medium-sized law firm in Australia were examined in regard to theories of worker mobility (matching, sectoral shift, and incentive). Results support a role for matching effects, but personnel practices affect the timing of turnover. Matching and incentive-based theories do not explain the high rates of turnover…

  18. Modelling assessment of oil sands pit lakes turn-over potential

    International Nuclear Information System (INIS)

    Mackenzie, I.; Vandenberg, J.; Lauzon, N.; Takyi, A.

    2006-01-01

    Pit lakes form when surface mining operations are discontinued and dewatering is terminated. Their use as a treatment step for oil sands surface mining reclamation waters was discussed. The goal of the End Pit Lake Subgroup of the Cumulative Environmental Management Association is to establish guidelines that will enable operators to achieve acceptable water quality for these lakes. Although both biological and physical processes affect turn-over potential, this presentation focused on the size of pit lakes, their depth, starting lake salinity concentrations, inflow rates and inflow salinity flux. These parameters where selected because of their influence on density gradients and turn-over potential. One-dimensional and two-dimensional modelling simulations were performed to examine turnover potential for a large range of pit lake configurations and conditions. The pit lake scenarios chosen for this modelling study included a wide range of changes in 3 lake sizes (1, 4 and 8 km 2 ), 3 lake depths (5, 20 and 50 m), 2 lake starting salinities (1 and 5 parts per thousand), 2 inflow rates (2 and 10 million m 3 per year), 3 starting inflow salinity concentrations (1, 2 and 4 parts per thousand) and 2 rates of influent salinity decrease (6- and 28- year half-life). Simulations showed that autumn is the governing season for determining turn-over potential. For the scenarios examined in this study, the expelling of salt from saline water upon ice formation and the effect of fresh water loading during spring melt events were not found to be significant factors governing turn-over potential. This presentation reviewed the DYRESM, CE-QUAL-W2, and RMA models used in this study. The conclusions reached by each model was also reviewed along with ongoing follow-up work

  19. Wind energy industry in Germany. Turnover and employment

    International Nuclear Information System (INIS)

    Keuper, A.; Schmidt, A.

    1994-01-01

    As a consequence of the growing wind energy market in Germany the importance of the industry in this business are has grown. In 1994 the turnover will go beyond 500 million DM, and the number of employees will reach 2,900. The turnover and the number of employees are increasing in spite of the higher efficiency. In 1994 only 5 employees are needed by a manufacturer to install 1 MW rated power instead of 15 in 1989, and the ratio of installed power to manufacturer's turnover has risen from 0,25 W/DM in 1988 to 0,455 W/DM in 1994. On the other hand the turnover of the manufacturers per employee has increased from 80,000 DM in 1988 to 440,000 DM in 1994. Economic development has considerably been advanced by subsidies for the application of wind energy technology. (orig.)

  20. Regulation of intestinal protein metabolism by amino acids.

    Science.gov (United States)

    Bertrand, Julien; Goichon, Alexis; Déchelotte, Pierre; Coëffier, Moïse

    2013-09-01

    Gut homeostasis plays a major role in health and may be regulated by quantitative and qualitative food intake. In the intestinal mucosa, an intense renewal of proteins occurs, at approximately 50% per day in humans. In some pathophysiological conditions, protein turnover is altered and may contribute to intestinal or systemic diseases. Amino acids are key effectors of gut protein turnover, both as constituents of proteins and as regulatory molecules limiting intestinal injury and maintaining intestinal functions. Many studies have focused on two amino acids: glutamine, known as the preferential substrate of rapidly dividing cells, and arginine, another conditionally essential amino acid. The effects of glutamine and arginine on protein synthesis appear to be model and condition dependent, as are the involved signaling pathways. The regulation of gut protein degradation by amino acids has been minimally documented until now. This review will examine recent data, helping to better understand how amino acids regulate intestinal protein metabolism, and will explore perspectives for future studies.

  1. Performance and turnover intentions: a social exchange perspective

    NARCIS (Netherlands)

    Biron, M.; Boon, C.

    2013-01-01

    Purpose - Prior research has yielded mixed results regarding the relationship between performance and turnover intentions. Drawing from social exchange theory, the purpose of this paper is to propose that the performance-turnover intentions association may be contingent upon individuals' exchange

  2. Substance Use Disorder Counselors’ Job Performance and Turnover after 1 Year: Linear or Curvilinear Relationship?1

    Science.gov (United States)

    Laschober, Tanja C.; de Tormes Eby, Lillian Turner

    2013-01-01

    The main goals of the current study were to investigate whether there are linear or curvilinear relationships between substance use disorder counselors’ job performance and actual turnover after 1 year utilizing four indicators of job performance and three turnover statuses (voluntary, involuntary, and no turnover as the reference group). Using longitudinal data from 440 matched counselor-clinical supervisor dyads, results indicate that overall, counselors with lower job performance are more likely to turn over voluntarily and involuntarily than not to turn over. Further, one of the job performance measures shows a significant curvilinear effect. We conclude that the negative consequences often assumed to be “caused” by counselor turnover may be overstated because those who leave both voluntarily and involuntarily demonstrate generally lower performance than those who remain employed at their treatment program. PMID:22527711

  3. Superintendent Turnover in Kentucky. Issues & Answers. REL 2011-No. 113

    Science.gov (United States)

    Johnson, Jerry; Huffman, Tyler; Madden, Karen; Shope, Shane

    2011-01-01

    This study examines superintendent turnover in Kentucky public school districts for 1998/99-2007/08, looking at how turnover varies by rural status, Appalachian and non-Appalachian region, and 2007/08 school district characteristics. Key findings include: (1) Kentucky school districts averaged one superintendent turnover during 1998/99-2007/08;…

  4. The effect of culture on the curvilinear relationship between performance and turnover.

    Science.gov (United States)

    Sturman, Michael C; Shao, Lian; Katz, Jan H

    2012-01-01

    Although researchers have theorized that there exists a curvilinear relationship between job performance and voluntary turnover, their research has been tested in the United States or culturally similar Switzerland. Through a study of the performance-turnover relationship from a multinational service-oriented organization in 24 countries, we demonstrate that the general relationship between performance and turnover is similar across countries but the details of that relationship change across countries. Using 4 cultural dimensions--in-group collectivism, power distance, uncertainty avoidance, and performance orientation--we find that cultural factors alter the overall probability of voluntary turnover and influence the degree of curvilinearity in the performance-turnover relationship. Our findings have implications for research on the performance-turnover relationship, turnover research, and practice.

  5. Eldecalcitol normalizes bone turnover markers regardless of their pre-treatment levels.

    Science.gov (United States)

    Shiraki, Masataka; Saito, Hitoshi; Matsumoto, Toshio

    2012-09-01

    Three-year treatment with eldecalcitol has been shown to improve lumbar and total hip bone mineral density (BMD), decrease bone turnover markers, and lower the incidences of vertebral and wrist fractures in patients with osteoporosis more than with treatment with alfacalcidol under vitamin D repletion. The purpose of this study was to determine whether there was a risk of eldecalcitol causing severely suppressed bone turnover in osteoporosis patients with low pre-treatment levels of bone turnover markers. Post-hoc analysis was conducted on the data from a 3-year, randomized, double-blind, active-comparator, clinical trial of eldecalcitol versus alfacalcidol under vitamin D repletion conducted in Japan. Enrolled patients with baseline measurements of bone turnover markers were stratified into tertiles according to their pre-treatment levels of serum bone-specific alkaline phosphatase, serum procollagen type I N-terminal propeptide, or urinary collagen-N-telopeptide. Eldecalcitol treatment rapidly reduced bone turnover markers, and kept them within the normal range. However, in the patients whose baseline values for bone turnover were low, eldecalcitol treatment did not further reduce bone turnover markers during the 3-year treatment period. Further long-term observation may be required to reach the conclusion. CLINICALTRIALS.GOV NUMBER: NCT00144456. Eldecalcitol normalizes, but does not overly suppress, bone turnover regardless of baseline levels of bone turnover markers. Thus, it is unlikely that eldecalcitol treatment will increase the risk of severely suppressed bone turnover and therefore deterioration of bone quality, at least for a treatment duration of 3 years.

  6. Organisational commitment and turnover intentions in humanitarian organisations

    NARCIS (Netherlands)

    Wijnmaalen, Julia; Heyse, Liesbet; Voordijk, Johannes T.

    2016-01-01

    Unwanted staff turnover is a prominent HRM problem in humanitarian organisations. In the profit sector, HRM tools such as pay, benefits, socialisation and training have proven to be effective in increasing organisational commitment and decreasing staff turnover. This study explores whether such

  7. Reviewing Employee Turnover: Focusing on Proximal Withdrawal States and an Expanded Criterion

    Science.gov (United States)

    Hom, Peter W.; Mitchell, Terence R.; Lee, Thomas W.; Griffeth, Rodger W.

    2012-01-01

    We reconceptualize employee turnover to promote researchers' understanding and prediction of why employees quit or stay in employing institutions. A literature review identifies shortcomings with prevailing turnover dimensions. In response, we expand the conceptual domain of the turnover criterion to include multiple types of turnover (notably,…

  8. Deubiquitylating enzyme USP9x regulates hippo pathway activity by controlling angiomotin protein turnover

    DEFF Research Database (Denmark)

    Nguyen, Thanh Hung; Andrejeva, Diana; Gupta, Rajat

    2016-01-01

    /TAZ activity. We demonstrate that USPx regulates ubiquitin-mediated turnover of the YAP inhibitor, Angiomotin. USP9x acts to deubiquitylate Angiomotin at lysine 496, resulting in stabilization of Angiomotin and lower YAP/TAZ activity. USP9x mRNA levels were reduced in several cancers. Clinically, USP9x m......RNA levels were reduced in several cancers with low USPx expression correlating with poor prognosis in renal clear cell carcinoma. Our data indicate that USP9x may be a useful biomarker for renal clear cell carcinoma....

  9. Occupational Health and Safety Management and Turnover Intention in the Ghanaian Mining Sector.

    Science.gov (United States)

    Amponsah-Tawiah, Kwesi; Ntow, Michael Akomeah Ofori; Mensah, Justice

    2016-03-01

    The mining industry is considered as one of the most dangerous and hazardous industries and the need for effective and efficient occupational health and safety management is critical to safeguard workers and the industry. Despite the dangers and hazards present in the mining industry, only few studies have focused on how occupational health and safety and turnover intentions in the mines. The study suing a cross-sectional survey design collected quantitative data from the 255 mine workers that were conveniently sampled from the Ghanaian mining industry. The data collection tools were standardized questionnaires that measured occupational health and safety management and turnover intentions. These scales were also pretested before their usage in actual data collection. The correlation coefficient showed that a negative relationship existed between dimensions of occupational health and safety management and turnover intention; safety leadership (r = -0.33, p safety facilities and equipment (r = -0.32, p safety procedure (r = -0.27, p safety leadership and safety facility were significant predictors of turnover intention, (β = -0.28, p safety leadership in ensuring the effective formulation of policies and supervision of occupational health and safety at the workplace. The present study demonstrates that safety leadership is crucial in the administration of occupational health and safety and reducing turnover intention in organizations.

  10. Plant traits and environment: floating leaf blade production and turnover of waterlilies

    Directory of Open Access Journals (Sweden)

    Peter F. Klok

    2017-04-01

    Full Text Available Floating leaf blades of waterlilies fulfill several functions in wetland ecosystems by production, decomposition and turnover as well as exchange processes. Production and turnover rates of floating leaf blades of three waterlily species, Nuphar lutea (L. Sm., Nymphaea alba L. and Nymphaea candida Presl, were studied in three freshwater bodies, differing in trophic status, pH and alkalinity. Length and percentages of leaf loss of marked leaf blades were measured weekly during the growing season. Area and biomass were calculated based on leaf length and were used to calculate the turnover rate of floating leaf blades. Seasonal changes in floating leaf production showed that values decreased in the order: Nymphaea alba, Nuphar lutea, Nymphaea candida. The highest production was reached for Nuphar lutea and Nymphaea alba in alkaline, eutrophic water bodies. The production per leaf was relatively high for both species in the acid water body. Nymphaea candida showed a very short vegetation period and low turnover rates. The ratio Total potential leaf biomass/Maximum potential leaf biomass (P/Bmax of the three species ranged from 1.35–2.25. The ratio Vegetation period (Period with floating leaves/Mean leaf life span ranged from 2.94–4.63, the ratio Growth period (Period with appearance of new floating leaves/Vegetation period from 0.53–0.73. The clear differences between Nymphaea candida versus Nuphar lutea and Nymphaea alba, may be due to adaptations of Nymphaea candida to an Euro-Siberic climate with short-lasting summer conditions.

  11. Turnover intention among intensive care unit nurses in Alexandria, Egypt.

    Science.gov (United States)

    Mosallam, Rasha; Hamidi, Samer; Elrefaay, Manal

    2015-06-01

    Given the difficulty in recruiting new nurses, it is imperative to retain those already in the profession. This cross-sectional study explored the relationship of demographic and work-related factors, burnout, conflict management and relationship between nurses and physicians on turnover intentions among ICU nurses in eight major hospitals in Alexandria, Egypt. Data on burnout, conflict management, nurse-physician communication, and turnover intention were collected by surveying 100 nurses in eight hospitals in Alexandria governorate. All nurses at the ICU of selected hospitals were approached (n=100) and a 47-item Likert scale questionnaire was administered to explore the factors affecting the turnover intention of ICU nurses in Alexandria. ICU nurses exhibited a mean score for turnover intention of 3.23 (mean score percentage 65.0%). There was a moderately positive statistically significant correlation between turnover intention and emotional exhaustion (r=0.29, Pturnover intention were emotional exhaustion and age. Nurses turnover intention at the ICU of the selected hospitals is high and is significantly associated with nurses' emotional exhaustion, poor nurse-physician communication, and nurses age.

  12. Literature review of labour turnover and absenteeism costs in the coal mining industry

    Energy Technology Data Exchange (ETDEWEB)

    Woolf, A.

    1977-01-01

    This paper includes labor turnover formulae, turnover costs, and turnover rates for the mining industry. Few meaningful studies or reports on absenteeism costs and labour turnover in mining were retrieved.

  13. Health insurance, cost expectations, and adverse job turnover.

    Science.gov (United States)

    Ellis, Randall P; Albert Ma, Ching-To

    2011-01-01

    Because less healthy employees value health insurance more than the healthy ones, when health insurance is newly offered job turnover rates for healthier employees decline less than turnover rates for the less healthy. We call this adverse job turnover, and it implies that a firm's expected health costs will increase when health insurance is first offered. Health insurance premiums may fail to adjust sufficiently fast because state regulations restrict annual premium changes, or insurers are reluctant to change premiums rapidly. Even with premiums set at the long run expected costs, some firms may be charged premiums higher than their current expected costs and choose not to offer insurance. High administrative costs at small firms exacerbate this dynamic selection problem. Using 1998-1999 MEDSTAT MarketScan and 1997 Employer Health Insurance Survey data, we find that expected employee health expenditures at firms that offer insurance have lower within-firm and higher between-firm variance than at firms that do not. Turnover rates are systematically higher in industries in which firms are less likely to offer insurance. Simulations of the offer decision capturing between-firm health-cost heterogeneity and expected turnover rates match the observed pattern across firm sizes well. 2010 John Wiley & Sons, Ltd.

  14. Workplace experiences and turnover intention among adult survivors of childhood cancer.

    Science.gov (United States)

    Crom, Deborah B; Ness, Kirsten K; Martinez, Larry R; Hebl, Michelle R; Robison, Leslie L; Hudson, Melissa M; Brinkman, Tara M

    2018-03-17

    The purpose of this study was to investigate workplace experiences and turnover intention (consideration of leaving or changing a job) and to examine factors associated with turnover intention among survivors. Adult survivors of childhood cancer with a history of employment (n = 289) completed measures of workplace experiences (n = 50, 18-29 years; n = 183, 30-44 years; n = 56; > 45 years of age at follow-up). Turnover intention was assessed using three items from the Job Satisfaction Scale. Responses were dichotomized as reflecting high vs. low turnover intention. Path analysis was used to estimate the influence of demographic characteristics, treatment exposures (cranial radiation therapy [CRT]), and workplace experiences on turnover intention. Thirty percent of survivors reported high turnover intention (95% CL, 25 to 36%). Exposure to CRT (P = 0.003), older attained age (P workplace discrimination (P = 0.008), and having lower continuance (P discrimination, mediated through job satisfaction, also influenced survivors' reported intent to leave their jobs. One third of adult survivors of childhood cancer report turnover intention, which is related to their cancer treatment, but more temporally proximal, workplace discrimination. Additional research is needed to understand the consequences of turnover intention among survivors. Survivors and their health care providers should be aware of legislative policies related to workplace discrimination (e.g., American with Disabilities Act) and related implications for job turnover.

  15. Engineered P450 biocatalysts show improved activity and regio-promiscuity in aromatic nitration.

    Science.gov (United States)

    Zuo, Ran; Zhang, Yi; Jiang, Chao; Hackett, John C; Loria, Rosemary; Bruner, Steven D; Ding, Yousong

    2017-04-12

    Nitroaromatics are among the most important and commonly used chemicals but their production often suffers from multiple unsolved challenges. We have previously described the development of biocatalytic nitration processes driven by an engineered P450 TxtE fusion construct. Herein we report the creation of improved nitration biocatalysts through constructing and characterizing fusion proteins of TxtE with the reductase domain of CYP102A1 (P450BM3, BM3R). The majority of constructs contained variable linker length while one was rationally designed for optimizing protein-protein interactions. Detailed biochemical characterization identified multiple active chimeras that showed improved nitration activity, increased coupling efficiency and higher total turnover numbers compared with TxtE. Substrate promiscuity of the most active chimera was further assessed with a substrate library. Finally, a biocatalytic nitration process was developed to nitrate 4-Me-DL-Trp. The production of both 4-Me-5-NO 2 -L-Trp and 4-Me-7-NO 2 -L-Trp uncovered remarkable regio-promiscuity of nitration biocatalysts.

  16. Species Turnover through Time: Colonization and Extinction Dynamics across Metacommunities.

    Science.gov (United States)

    Nuvoloni, Felipe Micali; Feres, Reinaldo José Fazzio; Gilbert, Benjamin

    2016-06-01

    Island biogeography and metacommunity theory often use equilibrium assumptions to predict local diversity, yet nonequilibrium dynamics are common in nature. In nonequilibrium communities, local diversity fluctuates through time as the relative importance of colonization and extinction change. Here, we test the prevalence and causes of nonequilibrium dynamics in metacommunities of mites associated with rubber trees distributed over large spatial (>1,000 km) and temporal (>30-60 generations) scales in Brazil. We measured colonization and extinction rates to test species turnover and nonequilibrium dynamics over a growing season. Mite metacommunities exhibited nonequilibrium dynamics for most months of the year, and these dynamics tracked climatic conditions. Monthly shifts in temperature of more than 1°C resulted in nonequilibrium dynamics, as did mean temperatures outside of two critical ranges. Nonequilibrium dynamics were caused by a change in colonization with temperature change and changes in both colonization and extinction with absolute temperature. Species turnover showed different trends; high relative humidity increased both colonization and extinction rates, increasing turnover but not nonequilibrium dynamics. Our study illustrates that testing nonequilibrium dynamics can provide new insights into the drivers of colonization, extinction, and diversity fluctuations in metacommunities.

  17. Computational model of collagen turnover in carotid arteries during hypertension.

    Science.gov (United States)

    Sáez, P; Peña, E; Tarbell, J M; Martínez, M A

    2015-02-01

    It is well known that biological tissues adapt their properties because of different mechanical and chemical stimuli. The goal of this work is to study the collagen turnover in the arterial tissue of hypertensive patients through a coupled computational mechano-chemical model. Although it has been widely studied experimentally, computational models dealing with the mechano-chemical approach are not. The present approach can be extended easily to study other aspects of bone remodeling or collagen degradation in heart diseases. The model can be divided into three different stages. First, we study the smooth muscle cell synthesis of different biological substances due to over-stretching during hypertension. Next, we study the mass-transport of these substances along the arterial wall. The last step is to compute the turnover of collagen based on the amount of these substances in the arterial wall which interact with each other to modify the turnover rate of collagen. We simulate this process in a finite element model of a real human carotid artery. The final results show the well-known stiffening of the arterial wall due to the increase in the collagen content. Copyright © 2015 John Wiley & Sons, Ltd.

  18. Explaining the Gap in Charter and Traditional Public School Teacher Turnover Rates

    Science.gov (United States)

    Stuit, David A.; Smith, Thomas M.

    2012-01-01

    This study uses national survey data to examine why charter school teachers are more likely to turnover than their traditional public school counterparts. We test whether the turnover gap is explained by different distributions of factors that are empirically and theoretically linked to turnover risk. We find that the turnover rate of charter…

  19. Bullying and employee turnover among healthcare workers: a three-wave prospective study.

    Science.gov (United States)

    Hogh, Annie; Hoel, Helge; Carneiro, Isabella G

    2011-09-01

    To investigate the risk of turnover among targets of bullying at work. Exposure to bullying seems to leave targets with intentions to leave their workplaces. However, it is uncertain to what extent they actually leave. Data were collected by questionnaires in a three-wave study among Danish healthcare workers at the time of graduation (T₁ ), 1 (T₂ ) and 2 years (T₃ ) later. We followed 2154 respondents who participated in all three waves. The first year after graduation, 9.2% reported being bullied at work, 1.8% frequently. Follow-up analyses showed a strong relationship between exposure to bullying at T₂ and turnover at T₃ [odds ratio (OR) for frequently bullied = 3.1]. The inclusion of push factors such as low social support and low sense of community, intention to leave and ill health did not change the relation between bullying and turnover significantly. Three reasons for quitting stood out among reasons given by the bullied respondents: poor leadership, being exposed to negative behaviour and health problems. Bullying may be costly to an organization in terms of staff turnover and subsequent recruitment and training of replacements. IMPACT FOR NURSING MANAGEMENT: Managers should regularly monitor the psychosocial work environment. To prevent bullying local policies and procedures should be developed, implemented and evaluated. 2011 Blackwell Publishing Ltd.

  20. Using the Job-Demands-Resources model to predict turnover in the information technology workforce – General effects and gender

    Directory of Open Access Journals (Sweden)

    Peter Hoonakker

    2014-01-01

    Full Text Available High employee turnover has always been a major issue for Information Technology (IT. In particular, turnover of women is very high. In this study, we used the Job Demand/Resources (JD-R model to examine the relationship between job demands and job resources, stress/burnout and job satisfaction/commitment, and turnover intention and tested the model for gender differences. Data were collected in five IT companies. A sample of 624 respondents (return rate: 56%; 54% males; mean age: 39.7 years was available for statistical analyses. Results of our study show that relationships between job demands and turnover intention are mediated by emotional exhaustion (burnout and relationships between job resources and turnover intention are mediated by job satisfaction. We found noticeable gender differences in these relationships, which can explain differences in turnover intention between male and female employees. The results of our study have consequences for organizational retention strategies to keep men and women in the IT work force.

  1. THE ROLE OF ORGANIZATIONAL COMMITMENT MEDIATION ON THE EFFECT OF PERSON-ORGANIZATION FIT AND JOB SATISFACTION TO TURNOVER INTENTION

    Directory of Open Access Journals (Sweden)

    Risma N.

    2018-02-01

    Full Text Available This study aimed to analyze and find out the role of organizational commitment mediation on the effect of person-organization fit and job satisfaction to the turnover intention of marketing funding employees. The research method used was quantitative. The type of this research was causal associative by using purposive sampling method in the sample determination. Respondents are 96 employees of Marketing Funding at Bank Nusa Tenggara Barat, Indonesia. The data analysis technique used was Partial Least Square analysis. The research result showed that person-organization fit has no significant effect on turnover intention, job satisfaction has no significant effect on turnover intention, person-organization fit has significant effect on the organizational commitment, job satisfaction has significant effect on organizational commitment, organizational commitment has significant effect on turnover intention, organizational commitment fully mediates the relationship between person-organization fit on turnover intention, and organizational commitment fully mediates the relationship between job satisfaction on turnover intention.

  2. Part of the job: the role of physical work conditions in the nurse turnover process.

    Science.gov (United States)

    Vardaman, James M; Cornell, Paul T; Allen, David G; Gondo, Maria B; Muslin, Ivan S; Mobley, Robin N; Brock, Meagan E; Sigmon, Tracy L

    2014-01-01

    Retention of nursing staff remains an important issue for health care managers. Turnover research has focused primarily on motivational and social factors as keys to retention, whereas the role of the physical work conditions has received considerably less attention. However, work design theory suggests that physical work conditions may be an important factor in fostering retention among nursing staff. The aim of this study was to integrate work design theory with turnover process models to explore the influence of perceptions of physical work conditions on the development of turnover intentions among nursing staff. Drawing on two samples of registered nurses working in cancer units in metropolitan hospitals in the southeastern United States, this study explores the impact of perceptions of physical work conditions on turnover intentions using ordinary least squares regression. Hypotheses are tested in Study 1 and replicated in Study 2. A measure of perceptions of physical work conditions is also developed and validated using exploratory (Study 1) and confirmatory (Study 2) factor analyses. Perceptions of physical work conditions explain variance in turnover intentions above than that explained by motivational and social factors. Specifically, employee perceptions of noisy work conditions are found to significantly increase turnover intentions, whereas perceptions that work conditions facilitate tasks were found to significantly reduce turnover intentions. Perceptions of temperature and health hazard did not show significant effects. Results suggest that health care managers and scholars should re-examine the role of physical work conditions in the turnover process. Investments in upgrades that facilitate tasks may foster retention better than investments that simply improve employee comfort. Negative perceptions of work conditions may have no impact if they are considered a normal "part of the job," although negative perceptions of conditions that are viewed as

  3. Work-life balance, job satisfaction and turnover intention amongst ...

    African Journals Online (AJOL)

    Work-life balance, job satisfaction and turnover intention amongst ... Employee turnover has signifi cant costs and negative consequences for ... However, no interaction effect was observed between overall work-life balance and job ...

  4. The role of job satisfaction, work engagement, self-efficacy and agentic capacities on nurses' turnover intention and patient satisfaction.

    Science.gov (United States)

    De Simone, Silvia; Planta, Anna; Cicotto, Gianfranco

    2018-02-01

    Nurses' voluntary turnover is a worrying global phenomenon which affects service quality. Retaining nursing staff within a hospital is important to eliminate the negative influence of voluntary turnover on the quality of care and organisation costs. This research helps explain nurses' voluntary turnover by analysing the role of self-efficacy, agentic capacities, job satisfaction, and work engagement on hospital turnover intention, and to study the relationships between these variables and patient satisfaction. This study gathered data from 194 nurses and 181 patients from 22 inpatient wards at two hospitals in southern Italy. Correlation analysis revealed that job satisfaction, work engagement, self-efficacy and agentic capacities were positively interrelated and negatively correlated with turnover intention. Path analysis showed that self-efficacy, some agentic capacities (anticipation and self-regulation), job satisfaction, and work engagement had direct or indirect effects on nurses' turnover intention, and that job satisfaction exerted a stronger effect on turnover intention. Also, patient satisfaction was positively correlated with nurses' job satisfaction, work engagement, self-efficacy, self-regulation and anticipation and negatively correlated with nurses' turnover intention. Results highlighted the importance of implementing actions (for example through feedforward methodology and the goal setting technique) to improve self-efficacy, self-regulation skill, work engagement and job satisfaction in order to reduce nurses' turnover intention and increase patient satisfaction with nursing care. Copyright © 2017 Elsevier Inc. All rights reserved.

  5. Health workforce acquisition, retention and turnover in southwest ...

    African Journals Online (AJOL)

    Background: Skill mix of health professionals, staff acquisition and turnover rate are among the major challenges for the delivery of quality health care. This study assessed the health workforce acquisition, retention, turnover rate and their intention to leave. Methods: A cross-sectional survey with quantitative and qualitative ...

  6. ON THE TURNOVER OF THE TULLY-FISHER RELATION

    NARCIS (Netherlands)

    RHEE, MH; PELETIER, RF; VANALBADA, TS

    1995-01-01

    The observed turnover at the high linewidth end of the infrared Tully-Fisher relation can be explained by the stellar population differences among galaxies. When the IRAS 60 mu m fluxes are added to the Tully-Fisher relation as a second parameter, the turnover disappears and the scatter becomes

  7. Relationship between perceived organizational politics, organizational trust, human resource management practices and turnover intention among Nigerian nurses

    Directory of Open Access Journals (Sweden)

    Ramatu Abdulkareem Abubakar

    2014-09-01

    Full Text Available Prior research has indicated that employee turnover is detrimental to both individuals and organisations. Because a turnover intention in the workplace is detrimental, several factors have been suggested to better understand the reasons why employees may decide to leave their organisations. Some of the organizational-related factors that have been considered by previous research include perceived organizational justice, job satisfaction, perceived psychological contract breach, and perceived organizational support, among others. Despite these empirical studies, literatures indicate that less attention has been paid to the influence of perceived organisational politics, organizational trust, and perceived human resource practices management (HRM practices on employee turnover. Hence, the present study fills in the gap by examining the relationship between perceived organisational politics, organizational trust, perceived human resource management practices and employee turnover among Registered Nurses in Nigerian public hospitals using multiple regression analysis technique. One hundred and seventy five Registered Nurses participated in the study. Result indicated that perceived organisational politics was significantly and positively related to turnover intentions. The result also showed that both organizational trust and perceived human resource practices were significantly and negatively related to turnover intentions. Theoretical and practical implications of the results are discussed.

  8. Identifying molecular effects of diet through systems biology: influence of herring diet on sterol metabolism and protein turnover in mice.

    Directory of Open Access Journals (Sweden)

    Intawat Nookaew

    Full Text Available BACKGROUND: Changes in lifestyle have resulted in an epidemic development of obesity-related diseases that challenge the healthcare systems worldwide. To develop strategies to tackle this problem the focus is on diet to prevent the development of obesity-associated diseases such as cardiovascular disease (CVD. This will require methods for linking nutrient intake with specific metabolic processes in different tissues. METHODOLOGY/PRINCIPAL FINDING: Low-density lipoprotein receptor-deficient (Ldlr -/- mice were fed a high fat/high sugar diet to mimic a westernized diet, being a major reason for development of obesity and atherosclerosis. The diets were supplemented with either beef or herring, and matched in macronutrient contents. Body composition, plasma lipids and aortic lesion areas were measured. Transcriptomes of metabolically important tissues, e.g. liver, muscle and adipose tissue were analyzed by an integrated approach with metabolic networks to directly map the metabolic effects of diet in these different tissues. Our analysis revealed a reduction in sterol metabolism and protein turnover at the transcriptional level in herring-fed mice. CONCLUSION: This study shows that an integrated analysis of transcriptome data using metabolic networks resulted in the identification of signature pathways. This could not have been achieved using standard clustering methods. In particular, this systems biology analysis could enrich the information content of biomedical or nutritional data where subtle changes in several tissues together affects body metabolism or disease progression. This could be applied to improve diets for subjects exposed to health risks associated with obesity.

  9. Effects of work environment and job characteristics on the turnover intention of experienced nurses: The mediating role of work engagement.

    Science.gov (United States)

    Wan, Qiaoqin; Li, Zhaoyang; Zhou, Weijiao; Shang, Shaomei

    2018-01-19

    To assess turnover intention among experienced nurses and explore the effects of work environment, job characteristics and work engagement on turnover intention. The nursing shortage is an urgent concern in China. A high turnover rate of experienced nurses could have serious effects on the quality of care, costs and the efficiency of hospitals. It is crucial to explore the predictors of turnover intention and develop strategies tailored to experienced nurses. A descriptive, cross-sectional survey design. A total of 778 experienced nurses from seven hospitals was surveyed on their work engagement, job characteristics, work environment and turnover intention in March-May 2017. Structural equation modelling was used to test a theoretical model and the hypotheses. The results showed that 35.9% of experienced nurses had high-level turnover intention. The final model explained 50% of the variance in experienced nurses' turnover intention and demonstrated that: (1) work environment was positively associated with higher work engagement and lower turnover intention and work engagement partially mediated the relationship between work environment and turnover intention; and (2) job characteristics were positively related to higher work engagement and lower turnover intention and work engagement fully mediated the relationship between job characteristics and turnover intention. The study confirms the intrinsic and extrinsic motivators on work engagement posited by job demands-resources model. Theory-driven strategies to improve work environment, enhance job characteristics and promote wok engagement are needed to address the nursing shortage and high turnover intention among experienced nurses. © 2018 John Wiley & Sons Ltd.

  10. Nursing staff turnover at a Swedish university hospital: an exploratory study.

    Science.gov (United States)

    Sellgren, Stina F; Kajermo, Kerstin N; Ekvall, Göran; Tomson, Göran

    2009-11-01

    The aim was to explore opinions on individual needs and other factors that may influence nursing staff turnover. High staff turnover is a great problem for many hospitals. It is shown to have a negative effect on the quality of nursing care and to increase hospital costs. In 2004 in a large university hospital in Sweden five focus group discussions (FGDs) including department heads (1), nursing managers (2) and members of nursing staff (2) were carried out. The questions to be addressed were 'Why do nurses leave?' and 'Why do nurses stay?' In addition, register data of staff turnover for 2002-2003 were analysed in relation to different facts about the units, such as number of employees, type of care and medical specialty. Categories of opinions identified in the FGDs were compared with results of the statistical analyses on the relationship between staff turnover and unit parameters to identify overall factors that may influence on nurse staff turnover. Four major factors were identified as having a possible influence on staff turnover: 'intrinsic values of motivation', 'work load', 'unit size 'and 'leadership'. Smaller units had lower staff turnover as well as outpatient units and day care. It was not possible to compare statements from participants from smaller units with those from participants from larger units. Two factors had diverging data, 'salary' and 'spirit of the time'. A surprising finding was the little mention of patient care in relation to staff turnover. It is important for managers to ensure that intrinsic values of nurses are met to minimise the risk for high turnover rates. Inpatient care must receive adequate staffing and nursing care could be organised into smaller units or work teams to avoid dissatisfaction and high turnover.

  11. Terrestrial carbon turnover time constraints on future carbon cycle-climate feedback

    Science.gov (United States)

    Fan, N.; Carvalhais, N.; Reichstein, M.

    2017-12-01

    Understanding the terrestrial carbon cycle-climate feedback is essential to reduce the uncertainties resulting from the between model spread in prognostic simulations (Friedlingstein et al., 2006). One perspective is to investigate which factors control the variability of the mean residence times of carbon in the land surface, and how these may change in the future, consequently affecting the response of the terrestrial ecosystems to changes in climate as well as other environmental conditions. Carbon turnover time of the whole ecosystem is a dynamic parameter that represents how fast the carbon cycle circulates. Turnover time τ is an essential property for understanding the carbon exchange between the land and the atmosphere. Although current Earth System Models (ESMs), supported by GVMs for the description of the land surface, show a strong convergence in GPP estimates, but tend to show a wide range of simulated turnover times (Carvalhais, 2014). Thus, there is an emergent need of constraints on the projected response of the balance between terrestrial carbon fluxes and carbon stock which will give us more certainty in response of carbon cycle to climate change. However, the difficulty of obtaining such a constraint is partly due to lack of observational data on temporal change of terrestrial carbon stock. Since more new datasets of carbon stocks such as SoilGrid (Hengl, et al., 2017) and fluxes such as GPP (Jung, et al., 2017) are available, improvement in estimating turnover time can be achieved. In addition, previous study ignored certain aspects such as the relationship between τ and nutrients, fires, etc. We would like to investigate τ and its role in carbon cycle by combining observatinoal derived datasets and state-of-the-art model simulations.

  12. SOME FEATURES OF CONTROL STAFF TURNOVER IN PERSONNEL MANAGEMENT

    Directory of Open Access Journals (Sweden)

    S. N. Kaznacheeva

    2015-01-01

    Full Text Available The author refers to the decision of the actual problem of staff turnover in the transformation of the Russian economy. In light of the problem of the effectiveness of human resources management the author indicates the most frequent problems faced by the company and focus on the problem of staff turnover. The author presents a different interpretation, defining "Marketing personnel" as a kind of administrative activity aimed at ensuring the long-term organization of human resources (identifying staffing needs, and these needs, that is, covering the organization's needs for personnel. It highlights the main features and distinctive features of marketing staff. We consider the objective (external and subjective reasons (internal reasons for staff turnover. The author proposes a number of measures to help identify the causes of turnover.

  13. Examining the temporal relationship between psychological climate, work attitude, and staff turnover

    Science.gov (United States)

    Garner, Bryan R.; Hunter, Brooke D.

    2012-01-01

    Relative to the broader industrial-organizational (I-O) psychology field, research on the turnover of substance use disorder (SUD) treatment staff is in its infancy. Despite its long and rich history, recent reviews of the turnover literature within I-O psychology have noted there remains considerable room for improvement. In particular, recommendations have been made for research that considers time in the turnover process and explores more distal causes of staff turnover. Addressing these gaps, this paper examined the temporal relationship between latent measures of psychological climate, work attitude, and staff turnover. Using data from 95 SUD treatment staff clustered within 29 treatment organizations, multilevel discrete-time survival analyses revealed that a latent measure of work attitude (e.g., job satisfaction, pay satisfaction, turnover intentions) fully mediated the temporal relationship between latent measures of psychological climate (e.g., supervisor support, coworker support, role conflict) and subsequent staff turnover. PMID:22658290

  14. Blind Spots: Small Rural Communities and High Turnover in the Superintendency

    Science.gov (United States)

    Kamrath, Barry; Brunner, C. Cryss

    2014-01-01

    This article examines high superintendency turnover through rural community members' perceptions of such attrition in their districts. Findings indicate that community members perceived high turnover as negative and believed that turnover was created by financial pressures, rural community resistance to educational trends, and bias against…

  15. The effects of sexual harassment on turnover in the military: time-dependent modeling.

    Science.gov (United States)

    Sims, Carra S; Drasgow, Fritz; Fitzgerald, Louise F

    2005-11-01

    Sexual harassment has consistently negative consequences for working women, including changes in job attitudes (e.g., lower satisfaction) and behaviors (e.g., increased work withdrawal). Cross-sectional evidence suggests that harassment influences turnover intentions. However, few studies have used actual turnover; rather, they rely on proxies. With a sample of 11,521 military servicewomen with turnover data spanning approximately 4 years, the authors used the appropriate method for longitudinal turnover data--Cox's regression--to investigate the impact of harassment on actual turnover. Experiences of harassment led to increased turnover, even after controlling for job satisfaction, organizational commitment, and marital status. Among officers, harassment also affected turnover over and above rank. Given turnover's relevance to organizational bottom lines, these findings have important implications not only for individual women but also for organizations. ((c) 2005 APA, all rights reserved).

  16. Bone turnover in postmenopausal osteoporosis

    International Nuclear Information System (INIS)

    Thomsen, K.

    1988-02-01

    Studies of the bone turnover in postmenopausal osteoporosis are essential, because the associated bone loss is inevitably due to the relative increase of bone resorption compared with bone formation. Measurement of the bone mineral content (BMC) in normal adults is assessed - partly on the uncorrected values and partly in proportion to the body muscle mass. The whole body retention (WBR) method is presented. The WBR and alternative urinary excretion (UE) methods used by the author are characterised and compared with the retention methods described in the literature. The representativity of WBR and UE for the estimation of bone turnover in normal subjects and patients with various bone metabolic diseases is discussed. The conclusion is that the modified retention methods used by the author have a satisfactory precision and accuracy in relation to the clinical studies carried out. The author's modification of the WBR method for determination of bone turnover and the alternative urinary excretion method (UE) consists in continuous scanning in the whole body count, using a gamma camera, and with the collimator a short distance from the volunteer. This procedure has the advantage of restricting the radioactive dose to 2 mCi (72 MBa). This is smaller by a factor of 5-10 than the dose used to measure WBR with equally simple counting equipment: With the author's procedure, using frontal counting, WBR is systematically underestimated by about 4 per cent point compared to the purely dorsal count, but since the frontal position is the most comfortable, requires a smaller radioactive dose, and the error is systematic, it is the preferred counting procedure. Correction of WBR and UE for bone mineral content is in principle a new parameter of bone turnover, whose improved accuracy increases the validity of the retention determinations. 136 refs. (EG)

  17. Telaah Hubungan Kepuasan Kerja Dan Komitmen Organisasional Terhadap Turnover Intention

    Directory of Open Access Journals (Sweden)

    Ali Amran

    2017-04-01

    ABSTRACT       Employees are the most important resources of company. They are human resources to do and move all of the activities of company. Therefore, company needs to keep and maintain their job satisfaction and organizational commitment in order to reduce the intention to leave the company (turnover intention. It is necessary to study the relationship among job satisfaction, organizational commitment and turnover intention. This will give benefit to determine the important values of employees’ job satisfaction and organizational commitment and its influences on turnover intention. The research methods are descriptive survey and verificative survey that is used to assess the performance of independent variables: those are job satisfaction and organizational commitment,  and dependent variable: that is turnover intention with doing observation to employees of PT. Alexindo Bekasi. The result of this research is there is influence of job satisfaction and organizational commitment on turnover intention. This research is the improvement of existing researches which can be applied in the other companies specially for the human resource or employee behavior field.   Keywords: Job Satisfaction, Organizational Commitment, Turnover Intention

  18. Organisational commitment and turnover intentions: evidence from Nigerian paramilitary organisation

    Directory of Open Access Journals (Sweden)

    Dotun Olaleye Faloye

    2014-09-01

    Full Text Available This study explores the empirical link between different dimensions of organizational commitment and turnover intentions on Nigeria paramilitary organisation. A literature review of organizational commitment and employee turnover provides the basis for the research hypotheses. Four research hypotheses were formulated and tested at 95% and 99% confidence level. The study adopted a survey research design. A self-administered questionnaire was used, involving 144 respondents from selected paramilitary organisation in Akure, Nigeria to collect data and testing the existing theory. Data collected were analysed using both descriptive and inferential statistical techniques. In contrary to theory, the study revealed a weak positive relationship between organizational commitment dimensions (affective, continuance and normative and turnover intentions. The relationships are statistically significant expect the one between turnover intention and normative commitment which is statistically insignificant. The study concluded that the commitment of an employee to organisational goals, missions, and values is not enough to predict his/her stay in the organisation. There are other variables apart from organisational commitment that are predictor of employees’ intentions to quit. Thus, organisations should look beyond forces in their internal environment, when considering reduction in employee’s turnover intentions and the actual employee’s turnover.

  19. Leave or Stay as a Risky Choice: Effects of Salary Reference Points and Anchors on Turnover Intention

    Science.gov (United States)

    Xiong, Guanxing; Wang, X. T.; Li, Aimei

    2018-01-01

    Within a risky choice framework, we examine how multiple reference points and anchors regulate pay perception and turnover intentions in real organizational contexts with actual employees. We hypothesize that the salary range is psychologically demarcated by three reference points into four regions, the minimum requirement (MR), the status quo (SQ), and the goal (G). Three studies were conducted: Study 1 analyzed the relationship between turnover intention and the subjective likelihood of falling into each of four expected salary regions; Study 2 tested the mediating effect of pay satisfaction on salary reference point-dependent turnover intention; and Study 3 explored the anchoring effect of estimated peer salaries. The results show that turnover intention was higher in the region below MR or between SQ and G but lower in the region above G or between MR and SQ. That is, turnover intention can be high even in situations of salary raise, if the raise is below a salary goal (i.e., leaving for a lack of opportunity) and low even in situations of salary loss, if the expected salary is still above the MR (i.e., staying for security). In addition, turnover intention was regulated by pay satisfaction and peer salaries. In conclusion, turnover intention can be viewed as a risky choice adapted to salary reference points. PMID:29872409

  20. THE RELATION BETWEEN EMOTIONAL LABOR, JOB BURNOUT AND INTENTION TO TURNOVER: A RESEARCH ON TRAVEL AGENCY WORKERS

    Directory of Open Access Journals (Sweden)

    Lokman TOPRAK

    2015-07-01

    Full Text Available The aim of this study is to show the relation between emotional labor, job burnout and intention to turnover of travel agency workers, and to develop appropriate suggestions in the light of obtained findings. For this aim, a survey is applied to travel agency workers which is one of the emotional labor-intensive jobs. According to the results of this research, emotional labor behaviors of travel agency workers influence job burnout negatively and their level of job burnout influences intention to turnover positively. However, any relation between emotional labor and intention to turnover was not found.

  1. Executive turnover: the influence of dispersion and other pay system characteristics.

    Science.gov (United States)

    Messersmith, Jake G; Guthrie, James P; Ji, Yong-Yeon; Lee, Jeong-Yeon

    2011-05-01

    Using tournament theory as a guiding theoretical framework, in this study, we assess the organizational implications of pay dispersion and other pay system characteristics on the likelihood of turnover among individual executives in organizational teams. Specifically, we estimate the effect of these pay system characteristics on executive turnover decisions. We use a multi-industry, multilevel data set composed of executives in publicly held firms to assess the effects of pay dispersion at the individual level. Consistent with previous findings, we find that pay dispersion is associated with an increased likelihood of executive turnover. In addition, we find that other pay characteristics also affect turnover, both directly and through a moderating effect on pay dispersion. Turnover is more likely when executives receive lower portions of overall top management team compensation and when they have more pay at risk. These conditions also moderate the relationship between pay dispersion and individual turnover decisions, as does receiving lower compensation relative to the market.

  2. Below the Surface of Special Education Administrator Turnover

    Science.gov (United States)

    Meeks, Amy

    2016-01-01

    The field of special education administration has experienced a shortage of high quality special education leadership candidates for several decades. If school districts are to effectively address the turnover of educational leaders, they must know what is happening that affects turnover of their leadership team. The intent of this study was to…

  3. Specificity and evolvability in eukaryotic protein interaction networks.

    Directory of Open Access Journals (Sweden)

    Pedro Beltrao

    2007-02-01

    Full Text Available Progress in uncovering the protein interaction networks of several species has led to questions of what underlying principles might govern their organization. Few studies have tried to determine the impact of protein interaction network evolution on the observed physiological differences between species. Using comparative genomics and structural information, we show here that eukaryotic species have rewired their interactomes at a fast rate of approximately 10(-5 interactions changed per protein pair, per million years of divergence. For Homo sapiens this corresponds to 10(3 interactions changed per million years. Additionally we find that the specificity of binding strongly determines the interaction turnover and that different biological processes show significantly different link dynamics. In particular, human proteins involved in immune response, transport, and establishment of localization show signs of positive selection for change of interactions. Our analysis suggests that a small degree of molecular divergence can give rise to important changes at the network level. We propose that the power law distribution observed in protein interaction networks could be partly explained by the cell's requirement for different degrees of protein binding specificity.

  4. Defects in MAP1S-mediated autophagy turnover of fibronectin cause renal fibrosis.

    Science.gov (United States)

    Xu, Guibin; Yue, Fei; Huang, Hai; He, Yongzhong; Li, Xun; Zhao, Haibo; Su, Zhengming; Jiang, Xianhan; Li, Wenjiao; Zou, Jing; Chen, Qi; Liu, Leyuan

    2016-05-01

    Excessive deposition of extracellular matrix proteins in renal tissues causes renal fibrosis and renal function failure. Mammalian cells primarily use the autophagy-lysosome system to degrade misfolded/aggregated proteins and dysfunctional organelles. MAP1S is an autophagy activator and promotes the biogenesis and degradation of autophagosomes. Previously, we reported that MAP1S suppresses hepatocellular carcinogenesis in a mouse model and predicts a better prognosis in patients suffering from clear cell renal cell carcinomas. Furthermore, we have characterized that MAP1S enhances the turnover of fibronectin, and mice overexpressing LC3 but with MAP1S deleted accumulate fibronectin and develop liver fibrosis because of the synergistic impact of LC3-induced over-synthesis of fibronectin and MAP1S depletion-caused impairment of fibronectin degradation. Here we show that a suppression of MAP1S in renal cells caused an impairment of autophagy clearance of fibronectin and an activation of pyroptosis. Depletion of MAP1S in mice leads to an accumulation of fibrosis-related proteins and the development of renal fibrosis in aged mice. The levels of MAP1S were dramatically reduced and levels of fibronectin were greatly elevated in renal fibrotic tissues from patients diagnosed as renal atrophy and renal failure. Therefore, MAP1S deficiency may cause the accumulation of fibronectin and the development of renal fibrosis.

  5. Turnover of registered nurses in Israel: characteristics and predictors.

    Science.gov (United States)

    Toren, Orly; Zelker, Revital; Lipschuetz, Michal; Riba, Shoshana; Reicher, Sima; Nirel, Nurit

    2012-05-01

    In an era of global and local nursing shortages, nursing turnover has negative consequences in terms of diminished quality of care, increased costs and economic losses and decreased job satisfaction. To examine the turnover rate of registered nurses in Israel by assessing the varying degree of turnover between economic sectors, between hospital and community facilities, and/or between types of hospitals; and by examining potential predicting factors of turnover among registered nurses. A national phone survey was undertaken in Israel consisting of a random sampling of registered nurses of working age (up to age 60). The subjects comprised 10% of a national database of 32,000 registered nurses. The turnover rate among working nurses in Israel currently stands at 23%. In addition, 13% of employed nurses have taken a temporary leave of absence for a period greater than 6 months in the past 10 years, most up to 1 year. While job satisfaction rates were relatively high (72%), Professional satisfaction rates were 60% with no significant difference between hospital and community nurses. The turnover rate of registered nurses from a hospital setting to the community was significantly higher (pcommunity registered nurses to hospitals. Predicting factors of turnover were found to be: young age, part-time work, lack of advanced professional education, academic education and low satisfaction with the nursing profession. The shift of nursing workforce is mainly from hospitals to community health settings. There is a need to monitor and understand the characteristics of job and professional satisfaction among hospital nurses in order to implement crucial organizational interventions and retain hospital nursing staffs. Since young nurses, nurses working part time and nurses with no advanced professional and academic education, tend to move more than others, efforts should be targeted at these specific groups. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.

  6. Protein turnover in lactating mink (Mustela vison) is not affected by dietary protein supply

    DEFF Research Database (Denmark)

    Tauson, Anne-Helene; Fink, Rikke; Chwalibog, André

    2006-01-01

    The mink is a strict carnivore and may therefore serve as a model for the cat. Current recommendations for protein supply for lactating mink are based on production experiments with preweaning kit growth as a measure of dietary adequacy (1,2). Recently, nitrogen balance and substrate oxidation have...... in humans (7), growing pigs (8), and growing rats (9). In adult cats, both protein synthesis and breakdown were lower when feeding a low- than when feeding a high-protein diet [20 vs. 70% of metabolizable energy (ME)5 from protein] (10). The objectives of this study were therefore to develop a ¹5N...

  7. Promoting retention of nurses: A meta-analytic examination of causes of nurse turnover.

    Science.gov (United States)

    Nei, Darin; Snyder, Lori Anderson; Litwiller, Brett J

    2015-01-01

    Because the health care field is expected to be the fastest growing job field until 2020, an urgent need to focus on nurse retention exists. The aim of this study was to examine the relationships between predictors of turnover (i.e., personal characteristics, role states, job characteristics, group/leader relations, organizational/environmental perceptions, attitudinal reactions) and turnover cognitions and intentions, as well as actual turnover among nurses, in an effort to determine the strongest predictors of voluntary turnover. Meta-analysis was used to determine best estimates of the effect of predictors on turnover based on 106 primary studies of employed nurses. Meta-analyzed correlations were subjected to path analysis to establish the structural relationships among the study variables. Supportive and communicative leadership, network centrality, and organizational commitment are the strongest predictors of voluntary turnover based on meta-analytic correlations. Additional variables that relate to nurse turnover intentions include job strain, role tension, work-family conflict, job control, job complexity, rewards/recognition, and team cohesion. The findings suggest that some factors, such as salary, are relatively less important in prediction of turnover. Administrators concerned about nurse turnover may more effectively direct resources toward altering certain job characteristics and work conditions in the effort to reduce voluntary turnover among nurses.

  8. Perceptions of hospital CEOs about the effects of CEO turnover.

    Science.gov (United States)

    Khaliq, Amir A; Thompson, David M; Walston, Stephen L

    2006-01-01

    Empirical evidence is scarce on chief executive officer (CEO) turnover in U.S. hospitals, with potentially serious implications for many of these organizations. This study, based on a nationwide survey of CEOs at non-federal general surgical and medical community hospitals conducted in the spring of 2004, reports the perceptions of hospital CEOs regarding the circumstances and impact of CEO turnover on U.S. hospitals. In the opinion of the respondents, the impact includes competitors taking advantage of turnover by luring employees and physicians away from the target hospital, significantly increasing the likelihood of other senior executives leaving the hospital, and many of the important strategic activities being delayed or cancelled altogether. Interestingly, the perceptions of CEOs regarding the effects of turnover do not seem to differ regardless of voluntary or involuntary circumstances of turnover. However, there is a notable bias in emphasizing the perceived negative implications of respondents' own departures and allegedly positive effects of their predecessors' departures.

  9. Accelerated collagen turnover in women with angina pectoris without obstructive coronary artery disease: An iPOWER substudy.

    Science.gov (United States)

    Nielsen, Signe H; Mygind, Naja D; Michelsen, Marie M; Bechsgaard, Daria F; Suhrs, Hannah E; Genovese, Federica; Nielsen, Henning B; Brix, Susanne; Karsdal, Morten; Prescott, Eva; Kastrup, Jens

    2018-05-01

    Aim Collagens are major cardiac extracellular matrix components, known to be actively remodelled and accumulated during diffuse myocardial fibrosis. We evaluated whether accelerated collagen turnover described by neo-epitope biomarkers reflecting collagen formation and degradation separates patients with diffuse myocardial fibrosis from asymptomatic controls. Methods and results Seventy-one women with angina pectoris without significant coronary artery disease assessed by invasive coronary angiogram were included. Competitive enzyme-linked immunosorbent assays (ELISAs) measuring circulating protein fragments in serum assessed the formation and degradation of collagen type III (Pro-C3, C3M and C3C), IV (P4NP7S and C4M), V (Pro-C5 and C5M) and VI (Pro-C6 and C6M), and degradation of collagen type I (C1M). Serum samples from 32 age-matched asymptomatic women were included as controls. Symptomatic women presented significantly elevated levels of Pro-C6, C3C, C3M, C4M and C8-C ( p angina pectoris, but without significant obstructive coronary artery disease, showed an imbalanced collagen turnover compared to asymptomatic controls. The examined biomarkers are tools to monitor active collagen remodelling in patients with angina pectoris, in risk of developing myocardial fibrosis.

  10. Turnover and employment in the German wind energy industry

    International Nuclear Information System (INIS)

    Keuper, A.

    1995-01-01

    Results of the fast growing wind energy market in 1994 are the turnover reaching more than 800 million DM, and the number of employees to about 3,700. In 1995 the manufacturers expect to need less than 4 employees to build and to install 1 MW rated power and to decrease the ratio of manufacturer's turnover per installed power unit to about 1900 DM/kW. In spite of this development it is expected that the turnover and the number of employees will increase due to the still fast growing market. (orig.)

  11. Superintendent Turnover in Kentucky. Summary. Issues & Answers. REL 2011-No. 113

    Science.gov (United States)

    Johnson, Jerry; Huffman, Tyler; Madden, Karen; Shope, Shane

    2011-01-01

    This study examines superintendent turnover in Kentucky public school districts for 1998/99-2007/08, looking at how turnover varies by rural status, Appalachian and non-Appalachian region, and 2007/08 school district characteristics. Key findings include: (1) Kentucky school districts averaged one superintendent turnover during 1998/99-2007/08;…

  12. Are nursing home survey deficiencies higher in facilities with greater staff turnover.

    Science.gov (United States)

    Lerner, Nancy B; Johantgen, Meg; Trinkoff, Alison M; Storr, Carla L; Han, Kihye

    2014-02-01

    To examine CNA and licensed nurse (RN+LPN/LVN) turnover in relation to numbers of deficiencies in nursing homes. A secondary data analysis of information from the National Nursing Home Survey (NNHS) and contemporaneous data from the Online Survey, Certification and Reporting (OSCAR) database. Data were linked by facility as the unit of analysis to determine the relationship of CNA and licensed nurse turnover on nursing home deficiencies. The 2004 NNHS used a multistage sampling strategy to generate a final sample of 1174 nursing homes, which represent 16,100 NHs in the United States. This study focused on the 1151 NNHS facilities with complete deficiency data. Turnover was defined as the total CNAs/licensed nurse full-time equivalents (FTEs) who left during the preceding 3 months (full- and part-time) divided by the total FTE. NHs with high turnover were defined as those with rates above the 75th percentile (25.3% for CNA turnover and 17.9% for licensed nurse turnover) versus all other facilities. This study used selected OSCAR deficiencies from the Quality of Care, Quality of Life, and Resident Behavior categories, which are considered to be more closely related to nursing care. We defined NHs with high deficiencies as those with numbers of deficiencies above the 75th percentile versus all others. Using SUDAAN PROC RLOGIST, we included NNHS sampling design effects and examined associations of CNA/licensed nurse turnover with NH deficiencies, adjusting for staffing, skill mix, bed size, and ownership in binomial logistic regression models. High CNA turnover was associated with high numbers of Quality of Care (OR 1.53, 95% CI 1.10-2.13), Resident Behavior (OR 1.42, 95% CI 1.03-1.97) and total selected deficiencies (OR 1.54, 95% CI 1.12-2.12). Licensed nurse turnover was significantly related to Quality of Care deficiencies (OR 2.06, 95% CI 1.50-2.82) and total selected deficiencies (OR 1.71, 95% CI 1.25-2.33). When both CNA turnover and licensed nurse turnover were

  13. Congruence in demersal fish, macroinvertebrate, and macroalgal community turnover on shallow temperate reefs.

    Science.gov (United States)

    Thomson, Russell J; Hill, Nicole A; Leaper, Rebecca; Ellis, Nick; Pitcher, C Roland; Barrett, Neville S; Edgar, Graham J

    2014-03-01

    To support coastal planning through improved understanding of patterns of biotic and abiotic surrogacy at broad scales, we used gradient forest modeling (GFM) to analyze and predict spatial patterns of compositional turnover of demersal fishes, macroinvertebrates, and macroalgae on shallow, temperate Australian reefs. Predictive models were first developed using environmental surrogates with estimates of prediction uncertainty, and then the efficacy of the three assemblages as biosurrogates for each other was assessed. Data from underwater visual surveys of subtidal rocky reefs were collected from the southeastern coastline of continental Australia (including South Australia and Victoria) and the northern coastline of Tasmania. These data were combined with 0.01 degree-resolution gridded environmental variables to develop statistical models of compositional turnover (beta diversity) using GFM. GFM extends the machine learning, ensemble tree-based method of random forests (RF), to allow the simultaneous modeling of multiple taxa. The models were used to generate predictions of compositional turnover for each of the three assemblages within unsurveyed areas across the 6600 km of coastline in the region of interest. The most important predictor for all three assemblages was variability in sea surface temperature (measured as standard deviation from measures taken interannually). Spatial predictions of compositional turnover within unsurveyed areas across the region of interest were remarkably congruent across the three taxa. However, the greatest uncertainty in these predictions varied in location among the different assemblages. Pairwise congruency comparisons of observed and predicted turnover among the three assemblages showed that invertebrate and macroalgal biodiversity were most similar, followed by fishes and macroalgae, and lastly fishes and invertebrate biodiversity, suggesting that of the three assemblages, macroalgae would make the best biosurrogate for

  14. Estimation of Employee Turnover with Competing Risks Models

    Directory of Open Access Journals (Sweden)

    Grzenda Wioletta

    2015-12-01

    Full Text Available Employee turnover accompanies every business organization, regardless of the industry and size. Nowadays, many companies struggle with problems related to the lack of sufficient information about the nature of employee turnover processes. Therefore, comprehensive analysis of these processes is necessary. This article aims to examine the turnover of employees from a big manufacturing company using competing risks models with covariates and without covariates. This technique allows to incorporate the information about the type of employment contract termination. Moreover, Cox proportional hazard model enables the researcher to analyse simultaneously multiple factors that affect employment duration. One of the major observations is that employee remuneration level differentiates most strongly the risk of job resignation.

  15. Missed nursing care: the impact on intention to leave and turnover.

    Science.gov (United States)

    Tschannen, Dana; Kalisch, Beatrice J; Lee, Kyung Hee

    2010-12-01

    The purpose of the study was to examine the relationship between missed nursing care, nurse turnover, and intention to leave. A cross-sectional study using the MISSCARE Survey was conducted. The sample comprised 110 patient-care units in 10 acute-care hospitals. Staffing data, turnover rates, and unit-level Case Mix Index were collected from the participating hospitals. Higher percentages of females on the unit were associated with lower turnover rates (beta = -.235, p = .010). Units with higher rates of missed care (beta = .302, p reduce intention to leave (and subsequent turnover).

  16. A retrospective analysis of employee turnover in the health care setting.

    Science.gov (United States)

    Bednar, B; McMullen, N

    1998-02-01

    Significant factors implicated in staff turnover include: variables in organizational structure; employee characteristics; needs and values, and the nature of tasks performed. This article will present the causative factors related to turnover and the conceptual models of the motivational theorists Maslow, Herzberg, Adams, and Mobley. No quantitative or qualitative research could be found on the potential causes of turnover in freestanding dialysis clinics. The staff turnover of a for-profit dialysis company for a 12 month period will be reported by job title, tenure, and level of job satisfaction.

  17. A Review of the Literature on Principal Turnover

    Science.gov (United States)

    Snodgrass Rangel, Virginia

    2018-01-01

    Among the many challenges facing public schools are high levels of principal turnover. Given the important role that principals play and are expected to play in the improvement process, concerns about principal turnover have resulted in a growing body of research on its causes and consequences. The purpose of this review is to take stock of what…

  18. How Teacher Turnover Harms Student Achievement. NBER Working Paper No. 17176

    Science.gov (United States)

    Ronfeldt, Matthew; Lankford, Hamilton; Loeb, Susanna; Wyckoff, James

    2011-01-01

    Researchers and policymakers often assume that teacher turnover harms student achievement, but recent evidence calls into question this assumption. Using a unique identification strategy that employs grade-level turnover and two classes of fixed-effects models, this study estimates the effects of teacher turnover on over 600,000 New York City 4th…

  19. Antecedents and consequence of employee turnover intention: Empirical evidence from Ghana

    Directory of Open Access Journals (Sweden)

    Michael A. Gyensare

    2015-08-01

    Full Text Available Guided by the theory of reasoned action, this study found support for the hypothesized inverse relationship between work-related factors and employee turnover intention on the one hand, and turnover intention and perceptions of accountable absence legitimacy on the other hand. Specifically, the higher employees’ turnover intent, the lower their perceptions about the accountability of their absence behavior and vice versa. The findings highlight the need to consider turnover intention as a salient construct that plays a dual role, first as a consequence variable to job satisfaction, affective and normative commitments, and next as an antecedent to accountable absence legitimacy in the workplace. The article concludes with a discussion on the significance of lessening employee turnover intent as a means of mitigating the perceptions of absence legitimacy in the workplace.

  20. The effect of the organizational socialization on organizational commitment and turnover intention with regard to moderate effect of career aspirations intention

    Directory of Open Access Journals (Sweden)

    Hossein Vazifehdust

    2014-02-01

    Full Text Available This paper discusses the influence of the Organizational socialization, on Organizational commitment and turnover intention with regard to moderate effect of career aspirations intention. Data were collected via a questionnaire from employees of east branches of social security organization of Tehran. Path analysis of data from 155 respondents was used to test 5 hypotheses. The results show organizational socialization has positive effect on organizational commitment, but negative effect on turnover intention moreover organizational commitment and career aspiration intention have positive effect on turnover intention. Further research should examine the different dimensions of macro-environmental condition on turnover intention.

  1. Turnover in intracranial aneurysm phantoms: its relation to neck size

    International Nuclear Information System (INIS)

    Chung, Tae Sub; Lee, Young Jun; Rhim, Yoon Chul

    2003-01-01

    To evaluate the physiologic background of aneurysms poorly visualized during 3D-TOF MRA, contrast-enhanced MRA (CEMRA) and DSA due to hemodynamic isolation. Using handmade elastic silicon phantoms to represent terminal basilar tip aneurysms, 3D-TOF MRA, CEMRA and DSA were used to determine blood turnover. Aneurysmal neck size was 2 mm and 10 mm, and the use of a pulsatile pump also helped recreate human physiologic parameters. We compared the results with those of computational fluid dynamics. DSA images of the narrow-necked aneurysm showed that a small volume of contrast medium washed into it during the systolic phase. As the width of its neck increased, the turnover volume of fragments of contrast bolus also increased. At CEMRA, the broad-necked aneurysm was visualized as the main bolus of Gd-DTPA passed through it, and at delayed CEMRA, the narrow-necked aneurysm was visualized faintly after the passage of bolus Gd-DTPA. The results correlated closely with those of 3D-TOF MRA and computational fluid dynamics. The visualization of intracranial aneurysms at 3D-TOF MRA, CEMRA and DSA was greatly dependent upon blood turnover, which varied according to aneurysmal neck size. A narrow-necked aneurysm might be missed at 3D-TOF MRA, CEMRA and DSA due to hemodynamic isolation

  2. The Impact of Human Resource Management Practices on Employee Turnover

    OpenAIRE

    Ozoliņa-Ozola, I

    2014-01-01

    The aim of this research was to identify the human resource management practices that are effective for employee turnover reducing. For this purpose the methods of document analysis and expert survey were used. On the basis of analysis of the scientific literature retrieved from academic databases the human resource management practices, which were mentioned in connection with employee turnover, were detected and described its effect on employee turnover. By conducting two separate expert sur...

  3. A case study into labour turnover within an NHS Trust.

    Science.gov (United States)

    Bamford, David; Hall, Catherine

    2007-02-01

    This paper investigates turnover in a British NHS Trust, to find out why staff left and whether factors identified in the literature with regards to improving turnover were pertinent to the organization. The research also investigated staff groups with high turnover--staff with less than 12 months service, and the unqualified nursing staff group--to ascertain whether there were any reasons for leaving or areas of dissatisfaction particular to these groups. The outcomes of the research complied with much of the published research with some interesting differences. The main reasons for leaving were identified as moving house, promotion or career development and taking up education and training opportunities elsewhere. There was no evidence of 'level of pay', commonly given as a significant influence behind turnover, as a reason for leaving. It was also found that the retention strategies identified in the published research were mainly applicable to the research, with evidence to support the improvement of line management skills, training and development, career development, appraisal, communications and induction in order to reduce turnover. There was less evidence for introducing work-life balance policies, improving communications, pay and working relationships as retention strategies. Recommendations for future management of labour turnover within the NHS Trust and elsewhere are made, with observations about the validity of some existing models. The core contribution of this research is in adding to the body of knowledge about labour turnover issues. This is of value to those working in the UK health-care and wider public sector. Specific recommendations for future research are made.

  4. Radiotracer studies on protein metabolism in different focuses of growth in vivo

    International Nuclear Information System (INIS)

    Rapoport, E.A.; Konikova, A.S.

    1979-01-01

    The role of various components of protein turnover in the liver growth induced by partial hepatectomy or phenobarbital as well as in malignant tumours has been studied with a radiotracer method. The ratio of the utilized precursors of exo- and endogenous origin during the formation of protein in focuses of growth, is labile, depends on a number of factors and varies even in the subcellular structures of the cell nucleus. It is probable that due to their reutilization through transreactions the protein structural units have in some focuses of growth and during formation of some proteins a definite superiority over the free aminoacids. It is also shown that the release of proteins and their degradation products from Walker 256 carcinosarcoma and the reutilization of proteins and their degradation products by sarcoma M-1 contribute to the protein turnover in the tumours. 8author)

  5. Effects of a preceptorship programme on turnover rate, cost, quality and professional development.

    Science.gov (United States)

    Lee, Tso-Ying; Tzeng, Wen-Chii; Lin, Chia-Huei; Yeh, Mei-Ling

    2009-04-01

    The purpose of the present study was to design a preceptorship programme and to evaluate its effects on turnover rate, turnover cost, quality of care and professional development. A high turnover rate of nurses is a common global problem. How to improve nurses' willingness to stay in their jobs and reduce the high turnover rate has become a focus. Well-designed preceptorship programmes could possibly decrease turnover rates and improve professional development. A quasi-experimental research design was used. First, a preceptorship programme was designed to establish the role and responsibilities of preceptors in instructing new nurses. Second, a quasi-experimental design was used to evaluate the preceptorship programme. Data on new nurses' turnover rate, turnover cost, quality of nursing care, satisfaction of preceptor's teaching and preceptor's perception were measured. After conducting the preceptorship programme, the turnover rate was 46.5% less than the previous year. The turnover cost was decreased by US$186,102. Additionally, medication error rates made by new nurses dropped from 50-0% and incident rates of adverse events and falls decreased. All new nurses were satisfied with preceptor guidance. The preceptorship programme effectively lowered the turnover rate of new nurses, reduced turnover costs and enhanced the quality of nursing care, especially by reducing medication error incidents. Positive feedback about the programme was received from new nurses. Study findings may offer healthcare administrators another option for retaining new nurses, controlling costs, improving quality and fostering professional development. In addition, incentives and effective support from the organisation must be considered when preceptors perform preceptorship responsibilities.

  6. A multilevel investigation on nursing turnover intention: the cross-level role of leader-member exchange.

    Science.gov (United States)

    Portoghese, Igor; Galletta, Maura; Battistelli, Adalgisa; Leiter, Michael P

    2015-09-01

    To analyse nursing turnover intention from the unit by using multilevel approach, examining at the individual level, the relationships between job characteristics, job satisfaction and turnover intention, and at the group level the role of leader-member exchange. Research on nursing turnover has given little attention to the effects of multilevel factors. Aggregated data of 935 nurses nested within 74 teams of four Italian hospitals were collected in 2009 via a self-administered questionnaire. Hierarchical linear modelling showed that job satisfaction mediated the relationship between job characteristics and intention to leave at the individual level. At the unit level, leader-member exchange was directly linked to intention to leave. Furthermore, cross-level interaction revealed that leader-member exchange moderated the relationship between job characteristics and job satisfaction. This study supported previous research in single-level turnover studies concerning the key role of job satisfaction, providing evidence that job characteristics are important in creating motivating and satisfying jobs. At the unit-level, leader-member exchange offers an approach to understand the role of unit-specific conditions created by leaders on nurses' workplace wellbeing. This study showed that it is important for nursing managers to recognise the relevance of implementing management practices that foster healthy workplaces centred on high-quality nurse-supervisor relationships. © 2014 John Wiley & Sons Ltd.

  7. Turnover of texture in low rate sputter-deposited nanocrystalline molybdenum films

    International Nuclear Information System (INIS)

    Druesedau, T.P.; Klabunde, F.; Loehmann, M.; Hempel, T.; Blaesing, J.

    1997-01-01

    The crystallite size and orientation in molybdenum films prepared by magnetron sputtering at a low rate of typical 1 (angstrom)s and a pressure of 0.45 Pa was investigated by X-ray diffraction and texture analysis. The surface topography was studied using atomic force microscopy. Increasing the film thickness from 20 nm to 3 microm, the films show a turnover from a (110) fiber texture to a (211) mosaic-like texture. In the early state of growth (20 nm thickness) the development of dome-like structures on the surface is observed. The number of these structures increases with film thickness, whereas their size is weakly influenced. The effect of texture turnover is reduced by increasing the deposition rate by a factor of six, and it is absent for samples mounted above the center of the magnetron source. The effect of texture turnover is related to the bombardment of the films with high energetic argon neutrals resulting from backscattering at the target under oblique angle and causing resputtering. Due to the narrow angular distribution of the reflected argon, bombardment of the substrate plane is inhomogeneous and only significant for regions close to the erosion zone of the magnetron

  8. How Multiple Interventions Influenced Employee Turnover: A Case Study.

    Science.gov (United States)

    Hatcher, Timothy

    1999-01-01

    A 3-year study of 46 textile industry workers identified causes of employee turnover (supervision, training, organizational communication) using performance analysis. A study of multiple interventions based on the analysis resulted in changes in orientation procedures, organizational leadership, and climate, reducing turnover by 24%. (SK)

  9. Coupled Model of Artificial Neural Network and Grey Model for Tendency Prediction of Labor Turnover

    Directory of Open Access Journals (Sweden)

    Yueru Ma

    2014-01-01

    Full Text Available The tendency of labor turnover in the Chinese enterprise shows the characteristics of seasonal fluctuations and irregular distribution of various factors, especially the Chinese traditional social and cultural characteristics. In this paper, we present a coupled model for the tendency prediction of labor turnover. In the model, a time series of tendency prediction of labor turnover was expressed as trend item and its random item. Trend item of tendency prediction of labor turnover is predicted using Grey theory. Random item of trend item is calculated by artificial neural network model (ANN. A case study is presented by the data of 24 months in a Chinese matured enterprise. The model uses the advantages of “accumulative generation” of a Grey prediction method, which weakens the original sequence of random disturbance factors and increases the regularity of data. It also takes full advantage of the ANN model approximation performance, which has a capacity to solve economic problems rapidly, describes the nonlinear relationship easily, and avoids the defects of Grey theory.

  10. Retaining your high performers: moderators of the performance-job satisfaction-voluntary turnover relationship.

    Science.gov (United States)

    Nyberg, Anthony

    2010-05-01

    Two divergent ideas explain the relationship between performance and voluntary turnover. One suggests that higher performing employees, who are rewarded for their superior work product, will desire to remain with an organization that values their performance and will, consequently, be less likely than lower performing employees to voluntarily leave. An alternative idea suggests that higher performing employees, who are more desirable to external companies as a result of their superior work product, will have more external job opportunities and will, consequently, be more likely than their lower performing colleagues to voluntarily leave. The current study evaluated the behaviors and attitudes of 12,545 insurance employees over a 3-year period to examine how these 2 divergent expectations influence the performance-voluntary turnover relationship. Results show that both pay growth and the relevant unemployment rate interact with performance to influence the performance-voluntary turnover relationship and that they work independently of employee job satisfaction influences. PsycINFO Database Record (c) 2010 APA, all rights reserved.

  11. Type VI collagen turnover-related peptides—novel serological biomarkers of muscle mass and anabolic response to loading in young men

    DEFF Research Database (Denmark)

    Nedergaard, Anders; Sun, Shu; Karsdal, Morten A

    2013-01-01

    Immobilization-induced loss of muscle mass is a complex phenomenon with several parallels to sarcopenic and cachectic muscle loss. Muscle is a large organ with a protein turnover that is orders of magnitude larger than most other tissues. Thus, we hypothesize that muscle loss and regain is reflec...

  12. Complexity Science and the Dynamics of Climate and Communication: Reducing Nursing Home Turnover

    Science.gov (United States)

    Anderson, Ruth A.; Corazzini, Kirsten N.; McDaniel, Reuben R.

    2008-01-01

    Purpose Turnover in nursing homes is a widespread problem adversely affecting care quality. Using complexity theory, we tested the effect of administrative climate, communication patterns, and the interaction between the two on turnover, controlling for facility context. Design and Methods Perceptions of administrative climate and communication were collected from 3,449 employees in 164 randomly sampled nursing homes, and they were linked to secondary data on facility characteristics, resource allocation, and turnover. We used hierarchical regression to test the hypotheses. Results Climate and communication both affected turnover, but lower turnover was dependent on the interaction between climate and communication. In nursing homes with reward-based administrative climates, higher levels of communication openness and accuracy explained lower turnover of licensed vocational nurses and certified nurse assistants, relative to nursing homes with an ambiguous climate. Adequate staffing and longer tenure of the nursing director were also important predictors of turnover. Implications Although context is important, managers can also influence turnover by addressing climate and communication patterns and by encouraging stable nursing leadership. PMID:15197292

  13. Exploring factors influencing voluntary turnover intent of Generation X public servants: A South African case

    Directory of Open Access Journals (Sweden)

    Hester Nienaber

    2012-12-01

    Full Text Available Purpose: The purpose of this article is to report on the factors perceived to influence the turnover intent of Generation X public servants. The problem: The researcher investigated the factors that Generation X public servants in South Africa perceive as influencing their turnover intent. Design: The problem was studied by way of a case study. The data were collected by means of semi-structured interviews. A total of eight purposively selected Generation X public servants participated in this study. Findings: The findings of the study show that the factors influencing the turnover intent of the Generation X public servants correspond to some of those proposed in the literature, including the nature of the job, traditional attitudes, and organisational context, both on the macro- and the micro-levels. Furthermore, these factors are also congruent with the drivers of engagement as set out in the literature, specifically content, coping, compensation, community and career. One of the implications of the findings of this study is that although the value of employees to organisations were established as long ago as the Renaissance, organisations still do not capitalise on their most important asset. It is in particular the direct (line manager that plays a crucial role in optimising the value-add of employees. Value: This study is original as it was the first to investigate the turnover intentions of Generation X public servants. Generation X employees are important as they are deemed to be the knowledge repositories of organisations and they are next in line to support the organisation when the Baby Boomers retire. The perceived turnover intentions correspond to some of the components of the generic turnover model proposed by Holtom et al. (2008. The question that arises is whether the turnover intentions of Generation X are any different from other generations. Conclusions: Given their unique characteristics, Generation X is a turnover risk, which

  14. DNA turnover and strand breaks in Escherichia coli

    International Nuclear Information System (INIS)

    Hanawalt, P.; Grivell, A.; Nakayama, H.

    1975-01-01

    The extent of DNA turnover has been measured in a dnaB mutant of Escherichia coli, temperature sensitive for semiconservative DNA replication. At the nonpermissive temperature about 0.02 percent of the deoxynucleotides in DNA are exchanged per generation period. This turnover rate is markedly depressed in the presence of rifampicin. During thymine starvation strand breaks accumulate in the DNA of E. coli strains that are susceptible to thymineless death. Rifampicin suppresses the appearance of these breaks, consistent with our hypothesis that transcription may be accompanied by repairable single-strand breaks in DNA. DNA turnover is enhanced severalfold in strands containing 5-bromodeoxyuridine in place of thymidine, possibly because the analog (or the deoxyuridine, following debromination) is sometimes recognized and excised

  15. Job and industry turnover for registered and licensed vocational nurses.

    Science.gov (United States)

    Spetz, Joanne; Rickles, Jordan; Chapman, Susan; Ong, Paul M

    2008-09-01

    Most studies of nurse turnover focus on job turnover, which could reflect nurse advancement and thus not be detrimental to the workforce. The authors discuss findings from a study that involved 2 cohorts of graduates from registered nursing and licensed vocational nursing community college programs in California. The duration of employment in the healthcare industry, as well as with specific employers, is tracked, lending a more thorough analysis of nursing job and industry turnover than found in other studies.

  16. Health care workplace discrimination and physician turnover.

    Science.gov (United States)

    Nunez-Smith, Marcella; Pilgrim, Nanlesta; Wynia, Matthew; Desai, Mayur M; Bright, Cedric; Krumholz, Harlan M; Bradley, Elizabeth H

    2009-12-01

    To examine the association between physician race/ ethnicity, workplace discrimination, and physician job turnover. Cross-sectional, national survey conducted in 2006-2007 of practicing physicians (n = 529) randomly identified via the American Medical Association Masterfile and the National Medical Association membership roster. We assessed the relationships between career racial/ethnic discrimination at work and several career-related dependent variables, including 2 measures of physician turnover, career satisfaction, and contemplation of career change. We used standard frequency analyses, odds ratios and chi2 statistics, and multivariate logistic regression modeling to evaluate these associations. Physicians who self-identified as nonmajority were significantly more likely to have left at least 1 job because of workplace discrimination (black, 29%; Asian, 24%; other race, 21%; Hispanic/Latino, 20%; white, 9%). In multivariate models, having experienced racial/ethnic discrimination at work was associated with high job turnover (adjusted odds ratio, 2.7; 95% CI, 1.4-4.9). Among physicians who experienced workplace discrimination, only 45% of physicians were satisfied with their careers (vs 88% among those who had not experienced workplace discrimination, p value workplace discrimination, p value Workplace discrimination is associated with physician job turnover, career dissatisfaction, and contemplation of career change. These findings underscore the importance of monitoring for workplace discrimination and responding when opportunities for intervention and retention still exist.

  17. Staff turnover in statewide implementation of ACT: relationship with ACT fidelity and other team characteristics.

    Science.gov (United States)

    Rollins, Angela L; Salyers, Michelle P; Tsai, Jack; Lydick, Jennifer M

    2010-09-01

    Staff turnover on assertive community treatment (ACT) teams is a poorly understood phenomenon. This study examined annual turnover and fidelity data collected in a statewide implementation of ACT over a 5-year period. Mean annual staff turnover across all observations was 30.0%. Turnover was negatively correlated with overall fidelity at Year 1 and 3. The team approach fidelity item was negatively correlated with staff turnover at Year 3. For 13 teams with 3 years of follow-up data, turnover rates did not change over time. Most ACT staff turnover rates were comparable or better than other turnover rates reported in the mental health and substance abuse literature.

  18. Job satisfaction mediates subjective social status and turnover intention among Chinese nurses.

    Science.gov (United States)

    Feng, Danjun; Su, Shan; Yang, Yang; Xia, Jinghua; Su, Yonggang

    2017-09-01

    Nurse turnover is one of the reasons for the global nurse shortage. Although previous studies have examined the determinants of turnover intention in detail, there is limited knowledge on the effect of subjective social status on nurse turnover intention. Therefore, in this study, we examined this relationship, including job satisfaction as a mediator, among Chinese nurses. This cross-sectional study employed questionnaires to assess subjective social status, job satisfaction, and turnover intention in 581 nurses who were randomly recruited from 10 hospitals in Jinan, China. The results partially supported our model. Although subjective social status exerted no significant direct effect on turnover intention, it exerted a significant indirect effect through job satisfaction. These results provide a new insight into why nurses leave their jobs, and possible new solutions to the nurse turnover problem. Efforts should be made to improve nurses' subjective social status. © 2017 John Wiley & Sons Australia, Ltd.

  19. The Modern Technologies to Reduce Turnover of Company Staff

    Directory of Open Access Journals (Sweden)

    Zaiko Tetiana O.

    2017-12-01

    Full Text Available The article is aimed at analyzing and substantiating the use in practice of modern technologies to reduce turnover of staff, which do not bear significant financial costs for the company. The authors have proved that non-material measures to reduce staff turnover in companies are becoming predominant nowadays. Among them as the most important are indicated: introduction of flexible schedule (mode of work, transition to the remote form of employment, and distribution of internal shares, in particular related to the strengthening of cohesion of staff, its team spirit. Also the reasons of transition from material to intangible factors of influence on conduct of workers have been disclosed. The advantages of non-material measures of the staff turnover reduction for both employees and employers were analyzed. For the first ones the most important are motivation and job satisfaction, while for the others it is reduction of staff turnover, formation of the responsible worker, improvement of quality and productivity of work.

  20. The Escherichia coli antiterminator protein BglG stabilizes the 5 ...

    Indian Academy of Sciences (India)

    Unknown

    Keywords. Antitermination; mRNA stability; RNA binding protein ... factor, Rho, and the pBR322 copy number protein, Rop, have been .... Transcription analysis using the oligo- ..... Retarded RNA turnover in Escherichia coli a means of main-.

  1. Dynamics of Adipocyte Turnover in Humans

    Energy Technology Data Exchange (ETDEWEB)

    Spalding, K; Arner, E; Westermark, P; Bernard, S; Buchholz, B; Bergmann, O; Blomqvist, L; Hoffstedt, J; Naslund, E; Britton, T; Concha, H; Hassan, M; Ryden, M; Frisen, J; Arner, P

    2007-07-16

    Obesity is increasing in an epidemic fashion in most countries and constitutes a public health problem by enhancing the risk for cardiovascular disease and metabolic disorders such as type 2 diabetes. Owing to the increase in obesity, life expectancy may start to decrease in developed countries for the first time in recent history. The factors determining fat mass in adult humans are not fully understood, but increased lipid storage in already developed fat cells is thought to be most important. We show that adipocyte number is a major determinant for the fat mass in adults. However, the number of fat cells stays constant in adulthood in lean and obese and even under extreme conditions, indicating that the number of adipocytes is set during childhood and adolescence. To establish the dynamics within the stable population of adipocytes in adults, we have measured adipocyte turnover by analyzing the integration of {sup 14}C derived from nuclear bomb tests in genomic DNA. Approximately 10% of fat cells are renewed annually at all adult ages and levels of body mass index. Neither adipocyte death nor generation rate is altered in obesity, suggesting a tight regulation of fat cell number that is independent of metabolic profile in adulthood. The high turnover of adipocytes establishes a new therapeutic target for pharmacological intervention in obesity.

  2. Phylogenetic turnover during subtropical forest succession across environmental and phylogenetic scales.

    Science.gov (United States)

    Purschke, Oliver; Michalski, Stefan G; Bruelheide, Helge; Durka, Walter

    2017-12-01

    Although spatial and temporal patterns of phylogenetic community structure during succession are inherently interlinked and assembly processes vary with environmental and phylogenetic scales, successional studies of community assembly have yet to integrate spatial and temporal components of community structure, while accounting for scaling issues. To gain insight into the processes that generate biodiversity after disturbance, we combine analyses of spatial and temporal phylogenetic turnover across phylogenetic scales, accounting for covariation with environmental differences. We compared phylogenetic turnover, at the species- and individual-level, within and between five successional stages, representing woody plant communities in a subtropical forest chronosequence. We decomposed turnover at different phylogenetic depths and assessed its covariation with between-plot abiotic differences. Phylogenetic turnover between stages was low relative to species turnover and was not explained by abiotic differences. However, within the late-successional stages, there was high presence-/absence-based turnover (clustering) that occurred deep in the phylogeny and covaried with environmental differentiation. Our results support a deterministic model of community assembly where (i) phylogenetic composition is constrained through successional time, but (ii) toward late succession, species sorting into preferred habitats according to niche traits that are conserved deep in phylogeny, becomes increasingly important.

  3. Is high employee turnover really harmful?: An empirical test using company records

    NARCIS (Netherlands)

    Glebbeek, A.C.; Bax, E.H.

    2004-01-01

    We tested the hypothesis that employee turnover and firm performance have an inverted U-shaped relationship: overly high or low turnover is harmful. Our analysis was based on economic performance data from 110 offices of a temporary employment agency. These offices had high variation in turnover but

  4. Peningkatan Komitmen Organisasi untuk Menurunkan Angka Turnover Karyawan

    Directory of Open Access Journals (Sweden)

    Elita Halimsetiono

    2014-05-01

    Full Text Available Komitmen organisasi dapat diartikan sebagai suatu sikap yang harus dimiliki oleh setiap pegawai untuk menunjukkan loyalitas terhadap organisasi tempat mereka bekerja. Pada dasarnya, komitmen organisasi berkaitan erat dengan aspek-aspek psikologis dalam menerima dan memercayai nilai-nilai dan tujuan organisasi yang muncul sebagai keinginan untuk tetap mempertahankan keanggotaan dalam organisasi. Permasalahan yang sering dikaitkan dengan rendahnya komitmen organisasi adalah pindah kerja (turnover. Masalah ini memiliki dampak yang merugikan organisasi karena dapat menghambat efektivitas dan efisiensi kerja yang selanjutnya akan menurunkan tingkat produktivitas organisasi. Oleh karena itu, untuk mencegah tingginya turnover karyawan, organisasi perlu meningkatkan komitmen organisasi karyawannya. Caranya adalah dengan mengetahui faktor-faktor apa saja yang memengaruhi komitmen organisasi dan bagaimana cara untuk meningkatkan komitmen organisasi tersebut. Artikel ini membahas faktor-faktor apa saja yang memengaruhi komitmen organisasi dan cara-cara yang dapat digunakan untuk meningkatkan komitmen organisasi sebagai upaya untuk menurunkan angka turnover karyawan. Organizational commitment can be interpreted as an attitude that should be owned by every employee to demonstrate loyalty to the organization where they work. Basically, organizational commitment is closely related to the psychological aspects in the acceptance and confidence to the values and objectives of the organization that are presented through the existence of a desire to maintain membership in the organization. Problems which are associated with low organizational commitment is turnover. This problem has an adverse impact on the organization because it can inhibit the effectiveness and efficiency of the work that would lower the level of productivity of the organization. Therefore, to prevent the high employee turnover, the organization should increase the organizational commitment of

  5. Does Judge Turnover Affect Judicial Performance?

    DEFF Research Database (Denmark)

    Guerra, Alice; Tagliapietra, Claudio

    2017-01-01

    office to another after three years of mandate, and the law prescribes their transfer after ten years to guarantee their independence. Flaws in the process managing the backlog of outbound judges and the existence of asynchrony between outbound and inbound transfers produce a chain of delays...... to the disposition of court cases. Using a novel dataset on Court of Appeal Districts in Italy (2008–2012), we provide evidence of a strong negative relation between high turnover rates and judicial performance. We find that marginal increases in judge turnover rates lead to a statistically significant decrease...... in judicial performance over two years of time...

  6. The evolutionary turnover of recombination hot spots contributes to speciation in mice.

    Science.gov (United States)

    Smagulova, Fatima; Brick, Kevin; Pu, Yongmei; Camerini-Otero, R Daniel; Petukhova, Galina V

    2016-02-01

    Meiotic recombination is required for the segregation of homologous chromosomes and is essential for fertility. In most mammals, the DNA double-strand breaks (DSBs) that initiate meiotic recombination are directed to a subset of genomic loci (hot spots) by sequence-specific binding of the PRDM9 protein. Rapid evolution of the DNA-binding specificity of PRDM9 and gradual erosion of PRDM9-binding sites by gene conversion will alter the recombination landscape over time. To better understand the evolutionary turnover of recombination hot spots and its consequences, we mapped DSB hot spots in four major subspecies of Mus musculus with different Prdm9 alleles and in their F1 hybrids. We found that hot spot erosion governs the preferential usage of some Prdm9 alleles over others in hybrid mice and increases sequence diversity specifically at hot spots that become active in the hybrids. As crossovers are disfavored at such hot spots, we propose that sequence divergence generated by hot spot turnover may create an impediment for recombination in hybrids, potentially leading to reduced fertility and, eventually, speciation. Published by Cold Spring Harbor Laboratory Press.

  7. Cogema in 1996: increasing turnover and stable net results

    International Nuclear Information System (INIS)

    Anon.

    1997-01-01

    This short article gives some financial informations about the Cogema group for 1996. The net result for 1996 reached 977 millions of French Francs (FF) with respect to 973 for the previous year. The turnover reached 34.427 billions of FF in 1996 and 30.611 in 1995, which represents a 12.5% growth. In the mining sector, the turnover has decreased to 2.853 billions of FF with respect to 3.238 in 1995. In the engineering and industry services sector the turnover of the overall companies, with the exception of Cogema, has considerably progressed (2.199 billions of FF in 1996, 1.738 in 1995). (J.S.)

  8. Diagnosing Causes of Teacher Retention, Mobility and Turnover: Guidelines for TIF Grantees

    Science.gov (United States)

    Finster, Matthew

    2015-01-01

    To effectively address teacher turnover, Teacher Incentive Fund (TIF) grantees need to follow an approach that entails aligning the tracking, diagnosing, and intervening processes. Unfortunately, too often retention strategies are implemented without regard to the various types of teacher turnover and specific data about the causes of turnover.…

  9. Turning Over Patient Turnover: An Ethnographic Study of Admissions, Discharges, and Transfers

    Science.gov (United States)

    Mowinski Jennings, Bonnie; Sandelowski, Margarete; Boshamer, Cary C.; Higgins, Melinda K.

    2014-01-01

    The impact on nursing work of patient turnover (admissions, discharges, and transfers) became evident in an ethnographic study of turbulence. The patient turnover data were generated from extensive observations, 21 formal interviews, and a year of admission and discharge records on one medical and one surgical unit. Timing of turnover events on the two units differed, but on both units admissions typically interrupted workflow more than did discharges, clustered admissions were more disruptive than staggered admissions, and patient turnover during change of shift was more disruptive than during medication administration. Understanding the complexity of patient turnover will elucidate the work involved and improve the evidence base for nurse staffing, a key determinant of quality and safety of care. PMID:24242196

  10. Current Proteomic Methods to Investigate the Dynamics of Histone Turnover in the Central Nervous System.

    Science.gov (United States)

    Farrelly, L A; Dill, B D; Molina, H; Birtwistle, M R; Maze, I

    2016-01-01

    Characterizing the dynamic behavior of nucleosomes in the central nervous system is vital to our understanding of brain-specific chromatin-templated processes and their roles in transcriptional plasticity. Histone turnover-the complete loss of old, and replacement by new, nucleosomal histones-is one such phenomenon that has recently been shown to be critical for cell-type-specific transcription in brain, synaptic plasticity, and cognition. Such revelations that histones, long believed to static proteins in postmitotic cells, are highly dynamic in neurons were only possible owing to significant advances in analytical chemistry-based techniques, which now provide a platform for investigations of histone dynamics in both healthy and diseased tissues. Here, we discuss both past and present proteomic methods (eg, mass spectrometry, human "bomb pulse labeling") for investigating histone turnover in brain with the hope that such information may stimulate future investigations of both adaptive and aberrant forms of "neuroepigenetic" plasticity. © 2016 Elsevier Inc. All rights reserved.

  11. Staff Turnover in Assertive Community Treatment (Act) Teams: The Role of Team Climate.

    Science.gov (United States)

    Zhu, Xi; Wholey, Douglas R; Cain, Cindy; Natafgi, Nabil

    2017-03-01

    Staff turnover in Assertive Community Treatment (ACT) teams can result in interrupted services and diminished support for clients. This paper examines the effect of team climate, defined as team members' shared perceptions of their work environment, on turnover and individual outcomes that mediate the climate-turnover relationship. We focus on two climate dimensions: safety and quality climate and constructive conflict climate. Using survey data collected from 26 ACT teams, our analyses highlight the importance of safety and quality climate in reducing turnover, and job satisfaction as the main mediator linking team climate to turnover. The findings offer practical implications for team management.

  12. Faunal turnover of marine tetrapods during the Jurassic-Cretaceous transition.

    Science.gov (United States)

    Benson, Roger B J; Druckenmiller, Patrick S

    2014-02-01

    Marine and terrestrial animals show a mosaic of lineage extinctions and diversifications during the Jurassic-Cretaceous transition. However, despite its potential importance in shaping animal evolution, few palaeontological studies have focussed on this interval and the possible climate and biotic drivers of its faunal turnover. In consequence evolutionary patterns in most groups are poorly understood. We use a new, large morphological dataset to examine patterns of lineage diversity and disparity (variety of form) in the marine tetrapod clade Plesiosauria, and compare these patterns with those of other organisms. Although seven plesiosaurian lineages have been hypothesised as crossing the Jurassic-Cretaceous boundary, our most parsimonious topology suggests the number was only three. The robust recovery of a novel group including most Cretaceous plesiosauroids (Xenopsaria, new clade) is instrumental in this result. Substantial plesiosaurian turnover occurred during the Jurassic-Cretaceous boundary interval, including the loss of substantial pliosaurid, and cryptoclidid diversity and disparity, followed by the radiation of Xenopsaria during the Early Cretaceous. Possible physical drivers of this turnover include climatic fluctuations that influenced oceanic productivity and diversity: Late Jurassic climates were characterised by widespread global monsoonal conditions and increased nutrient flux into the opening Atlantic-Tethys, resulting in eutrophication and a highly productive, but taxonomically depauperate, plankton. Latest Jurassic and Early Cretaceous climates were more arid, resulting in oligotrophic ocean conditions and high taxonomic diversity of radiolarians, calcareous nannoplankton and possibly ammonoids. However, the observation of discordant extinction patterns in other marine tetrapod groups such as ichthyosaurs and marine crocodylomorphs suggests that clade-specific factors may have been more important than overarching extrinsic drivers of faunal

  13. Protein intake does not increase vastus lateralis muscle protein synthesis during cycling

    DEFF Research Database (Denmark)

    Hulston, CJ; Wolsk, Emil; Grøndahl, Thomas Sahl

    2011-01-01

    PURPOSE: This study aimed to investigate the effect of protein ingestion on leg protein turnover and vastus lateralis muscle protein synthesis during bicycle exercise and recovery. METHODS: Eight healthy males participated in two experiments in which they ingested either a carbohydrate solution...... sampling, and blood flow measurements. Muscle protein synthesis was calculated from the incorporation of l-[ring-C6]phenylalanine into protein. RESULTS: Consuming protein during exercise increased leg protein synthesis and decreased net leg protein breakdown; however, protein ingestion did not increase...... protein synthesis within the highly active vastus lateralis muscle (0.029%·h(-1), ± 0.004%·h(-1), and 0.030%·h(-1), ± 0.003%·h(-1), in CHO and CHO + P, respectively; P = 0.88). In contrast, consuming protein, during exercise and recovery, increased postexercise vastus lateralis muscle protein synthesis...

  14. Factors influencing turnover intention among registered nurses in Samar Philippines.

    Science.gov (United States)

    Labrague, Leodoro J; Gloe, Donna; McEnroe, Denise M; Konstantinos, Kostas; Colet, Paolo

    2018-02-01

    Despite the massive nurse migration and turnover of nurses in the Philippines, there remains a lack of studies describing factors influencing the migration of Filipino nurses. This study explored the effects of nurses' characteristics, work satisfaction, and work stress with the intent to leave an organization among registered nurses in the Philippines. This study utilized a descriptive, cross-sectional approach. One hundred sixty six (166) nurses participated in the study during the months of September 2015 to December 2015. Three standardized instruments were used in the study: Job Satisfaction Index (JSI), Job Stress Scale (JSS), and Turnover Intention Inventory Scale (TIIS). Data were analyzed using descriptive and inferential statistical tools. Nurses' ages were found to significantly influence their turnover intentions. Job satisfaction (β=-0.47, p=0.001) and job stress (β=0.23, p=0.001) strongly predicted turnover intentions in the nurses. The mean values for the job satisfaction scale, job stress scale, and turnover intention inventory scale were 3.13 (SD=0.60), 2.74 (SD=0.71), and 2.43 (SD=0.67) respectively. Several predictors of turnover intentions were determined in this study through nurses' age, job satisfaction, and job stress as being the most influential factors. Efforts to increase nurses' job satisfaction and reduce job stress should be implemented to halt further loss of these skilled groups of healthcare professionals. Copyright © 2017 Elsevier Inc. All rights reserved.

  15. Non-invasive quantification of collagen turnover in renal transplant recipients.

    Directory of Open Access Journals (Sweden)

    Elisabeth G D Stribos

    Full Text Available Kidney allograft failure due to chronic injury/rejection remains the main cause of graft loss in renal transplant recipients (RTR. Here, we investigated whether specific biomarkers of extracellular matrix (ECM turnover are associated with allograft function and chronic kidney disease (CKD stage in RTR. Seventy-eight patients who attended the University Medical Center Groningen for a routine check-up after kidney transplantation were enrolled in the study. Plasma and/or 24h-urine samples were collected and specific matrix-metalloproteinase-generated neo-epitope fragments of collagens were measured by enzyme-linked immunosorbent assay. Our results demonstrated that urinary levels of C3M, a marker for collagen type III degradation, correlated with estimated glomerular filtration rate (eGFR; r = 0.58, p<0.0001, with lower levels detected in the urine of patients with advanced CKD. In addition, plasma levels of Pro-C6, a marker for collagen type VI formation, significantly increased with disease progression and correlated with eGFR (r = -0.72, p<0.0001. Conversely, plasma C3M and urinary Pro-C6 levels showed no correlation with renal function. We identified two neo-epitope biomarkers of tissue turnover associated with ECM remodeling and fibrosis that can stratify patients by CKD stage. This is as promising first step towards non-invasive monitoring of ECM turnover in the kidneys.

  16. Staff turnover in statewide implementation of ACT: relationship with ACT fidelity and other team characteristics

    OpenAIRE

    Rollins, Angela L.; Salyers, Michelle P.; Tsai, Jack; Lydick, Jennifer M.

    2010-01-01

    Staff turnover on assertive community treatment (ACT) teams is a poorly understood phenomenon. This study examined annual turnover and fidelity data collected in a statewide implementation of ACT over a 5-year period. Mean annual staff turnover across all observations was 30.0%. Turnover was negatively correlated with overall fidelity at Year 1 and 3. The team approach fidelity item was negatively correlated with staff turnover at Year 3. For 13 teams with 3 years of follow-up data, turnover ...

  17. Extensive Turnover of Compatible Solutes in Cyanobacteria Revealed by Deuterium Oxide (D_2O) Stable Isotope Probing

    International Nuclear Information System (INIS)

    Baran, Richard; Lau, Rebecca; Bowen, Benjamin P.; Diamond, Spencer; Jose, Nick

    2017-01-01

    In diverse environments on a global scale cyanobacteria are important primary producers of organic matter. Moreover, while mechanisms of CO_2 fixation are well understood, the distribution of the flow of fixed organic carbon within individual cells and complex microbial communities is less well characterized. To obtain a general overview of metabolism, we describe the use of deuterium oxide (D_2O) to measure deuterium incorporation into the intracellular metabolites of two physiologically diverse cyanobacteria: a terrestrial filamentous strain (Microcoleus vaginatus PCC 9802) and a euryhaline unicellular strain (Synechococcus sp. PCC 7002). D_2O was added to the growth medium during different phases of the diel cycle. Incorporation of deuterium into metabolites at nonlabile positions, an indicator of metabolite turnover, was assessed using liquid chromatography mass spectrometry. Expectedly, large differences in turnover among metabolites were observed. Some metabolites, such as fatty acids, did not show significant turnover over 12–24 h time periods but did turn over during longer time periods. Unexpectedly, metabolites commonly regarded to act as compatible solutes, including glutamate, glucosylglycerol, and a dihexose, showed extensive turnover compared to most other metabolites already after 12 h, but only during the light phase in the cycle. We observed extensive turnover and found it surprising considering the conventional view on compatible solutes as biosynthetic end points given the relatively slow growth and constant osmotic conditions. Our suggests the possibility of a metabolic sink for some compatible solutes (e.g., into glycogen) that allows for rapid modulation of intracellular osmolarity. To investigate this, uniformly "1"3C-labeled Synechococcus sp. PCC 7002 were exposed to "1"2C glucosylglycerol. Following metabolite extraction, amylase treatment of methanol-insoluble polymers revealed "1"2C labeling of glycogen. Overall, our work shows that D_2

  18. Employee turnover and productivity among small business entities in Nigeria

    Directory of Open Access Journals (Sweden)

    John N. N. Ugoani

    2016-12-01

    Full Text Available This study was designed to evaluate the problems of employee turnover on productivity among small business entities in Nigeria, and recommend remedial actions. Employee turnover is the separation of employees from employers and replacement with other employees. Productive manpower is a critical element for the economic survival of any small business entity. The survey research design was used for the study. The sample comprised of 320 respondents. Data generated were analyzed by using descriptive, and Z-test statistical techniques. It was found that employee turnover adversely affects productivity in small business entities.

  19. Exit interviews to reduce turnover amongst healthcare professionals.

    Science.gov (United States)

    Webster, Joan; Flint, Anndrea

    2014-08-19

    Exit interviews are widely used in healthcare organisations to identify reasons for staff attrition, yet their usefulness in limiting turnover is unclear. To determine the effectiveness of various exit interview strategies in decreasing turnover rates amongst healthcare professionals. We searched the Cochrane EPOC Group Specialised Register; Cochrane Central Register of Controlled Trials (CENTRAL), Issue 11, 2012; MEDLINE, Ovid (1950- ); EMBASE, Ovid (1947- ); CINAHL, EbscoHost (1980- ), and PsycINFO, OVID (1806-) between October 31 and November 6, 2012. We also screened the reference lists of included studies and relevant reviews; and searched trial registries for planned and on-going studies. We did not restrict searches by language or publication date. Randomised controlled trials, controlled clinical trials, controlled before-after studies and interrupted time series studies comparing turnover rates between healthcare professionals who had undergone one form of exit interview with another form of exit interview or with no interview. Two review authors independently assessed trial quality and extracted data. The original search identified 1560 citations, of which we considered 19 potentially relevant. The two authors independently reviewed the abstracts of these studies and retrieved the full texts of eight studies. We excluded all eight following independent assessment; they were either interviews, commentaries on how to do an exit interview or descriptive studies about reasons for leaving. We found no studies that matched our inclusion criteria. For this first update, we screened 2220 citations and identified no new studies. Evidence about the effectiveness of exit interviews to reduce turnover is currently not available. However, exit interviews may provide useful information about the work environment which, in turn, may be useful in the development of interventions to reduce turnover.

  20. Estimating Cause: Teacher Turnover and School Effectiveness in Michigan

    Science.gov (United States)

    Keesler, Venessa; Schneider, Barbara

    2010-01-01

    The purpose of this paper is investigate issues related to within-school teacher supply and school-specific teacher turnover within the state of Michigan using state administrative data on Michigan's teaching force. This paper 1) investigates the key predictors of teacher turnover and mobility, 2) develops a profile of schools that are likely to…

  1. Roles of perceived exchange quality and organisational identification in predicting turnover intention

    Directory of Open Access Journals (Sweden)

    Manish Kumar

    2012-03-01

    Full Text Available This paper explores whether the perceived quality of the leader–member exchange and the general environment of exchange could predict turnover intention. It further examines the role of organisational identification as an explanatory variable mediating between exchange relationships and turnover intention. The authors used three-step hierarchical linear regressions on a data set collected in two time waves. The results supported the mediating role of organisational identification for the leader–member exchange and turnover intention relationship as well as the general environment of exchange and turnover intention relationship. Moreover, as was expected, the general exchange quality had a greater impact on organisational identification compared to the leader–member exchange quality. However, the findings did not confirm the expected trend in the case of two exchange variables predicting turnover intention.

  2. Calculation of turnover rates in stable-isotope studies

    International Nuclear Information System (INIS)

    Wootton, R.; Ford, G.C.; Cheng, K.N.; Halliday, D.

    1985-01-01

    In a comparison of glucose turnover measured with 2 H-glucose and with 13 C-glucose Tserng and Kalhan used five apparently different equations and obtained conflicting answers. There is, however, no difference in principle between the use of a stable isotope as a tracer and the use of a radioactive isotope, and the rate of appearance of tracee in a steady-state system (the turnover) can therefore be shown to be proportional to the equilibrium dilution of the infused tracer. Because the sensitivity of measurement of this dilution made using a gas chromatograph-mass spectrometer is lower than that made by radioactivity measurement, the contribution to the measured turnover rate due to the infusate cannot be neglected, as it usually is in radioisotope work. A convenient calibration curve to establish this dilution is the mole ratio of the pure infusate against the area ratio for the relevant ions. Tserng and Kalhan's apparently conflicting results for glucose-turnover using 13 C-glucose as the tracer can all be shown to amount to approximately 11.6 μmol min -1 kg -1 . This value is only slightly lower (0.05 2 H-glucose as the tracer and supports the use of 13 C-glucose as an alternative. (author)

  3. PENGARUH JOB SATISFACTION TERHADAP OCB DAN TURNOVER INTENTION

    Directory of Open Access Journals (Sweden)

    Febru Rida Ningsih

    2015-06-01

    Full Text Available This article aims to provide the impact of job satisfaction to OCB and turnover intention. This study used a quantitative method with a statistical analysis. Simple analysis regression used to test each hypotheses. The object of this research is a branch of national bank. Population in this research are entire employees of a brach of national bank that is e non frontliner employees. Non-probability sampling is used of this reseach. The measurement of job satiafaction and turnover intention variables used likert scale that developed by Rinaldi (2008 and measurement of OCB variable adopted from  Organ (1988.  The result of this research has shown that hypotheses one is rejected and hypotheses two is accepted. Eventually, through this article, an understanding that job satisfaction does not significantly influence to OCB but job satisfaction has significant influence to turnover intention.

  4. Mentoring and turnover intentions in public accounting firms: a research note

    OpenAIRE

    Matthew Hall; David Smith

    2009-01-01

    Turnover in public accounting firms is a critically important issue as firms seek to retain quality accounting personnel in the face of skilled labour shortages. Mentoring is one initiative that has been suggested as a means of reducing the high costs associated with employee turnover. However, prior accounting research examining the association between mentoring and turnover intentions has produced mixed results, which may be due, at least in part, to difficulties in operationalizing the men...

  5. The mediating role of emotional exhaustion in the relationship of mindfulness with turnover intentions and job performance

    OpenAIRE

    Reb, J; Narayanan, J; Chaturvedi, S; Ekkirala, S

    2016-01-01

    The role of mindfulness in the workplace has emerged as a legitimate and growing area of organizational scholarship. T he present research examined the role of employee emotional exhaustion in mediating the relationship of mindfulness with turnover intentions and task performance . Drawing on theory and empirical research on both organizational behavior and mindfulness, w e predicted that more mindful employees would show lower turnover intentions and higher task performance and that th e s e...

  6. Nurse Knowledge, Work Environment, and Turnover in Highly Specialized Pediatric End-of-Life Care.

    Science.gov (United States)

    Lindley, Lisa C; Cozad, Melanie J

    2017-07-01

    To examine the relationship between nurse knowledge, work environment, and registered nurse (RN) turnover in perinatal hospice and palliative care organizations. Using nurse intellectual capital theory, a multivariate analysis was conducted with 2007 National Home and Hospice Care Survey data. Perinatal hospice and palliative care organizations experienced a 5% turnover rate. The professional experience of advanced practice nurses (APNs) was significantly related to turnover among RNs (β = -.032, P < .05). Compared to organizations with no APNs professional experience, clinical nurse specialists and nurse practitioners significantly reduced RN turnover by 3 percentage points. No other nurse knowledge or work environment variables were associated with RN turnover. Several of the control variables were also associated with RN turnover in the study; Organizations serving micropolitan (β = -.041, P < .05) and rural areas (β = -.037, P < .05) had lower RN turnover compared to urban areas. Organizations with a technology climate where nurses used electronic medical records had a higher turnover rate than those without (β = .036, P < .05). The findings revealed that advanced professional experience in the form of APNs was associated with reductions in RN turnover. This suggests that having a clinical nurse specialist or nurse practitioner on staff may provide knowledge and experience to other RNs, creating stability within the organization.

  7. Determinants of CEO Turnover in Publicand Private Firms in Denmark - CEO and Firm Characteristics

    DEFF Research Database (Denmark)

    Sponholtz, Carina

    In this study we are the first to draw on longitudinal matched employer-employee data to study CEO turnover. Using this data we contribute tothe existing literature by examining the e¤ect of previously unstudied in-dividual characteristics on CEO turnover. Additionally, we are able toexamine CEO...... turnover. Finally, the inverse relationshipbetween firm performance and CEO turnover only exists in LLL firms(larger limited liability firms, both publicly and privately held), whereagency costs are assumed and found to be highest.In this study we are the first to draw on longitudinal matched employer-employee...... turnover across a variety of firm types that di¤er with re-spect to the corporate governance issues they face. Our simple methodol-ogy to define CEO turnover results in turnover rates similar to those foundpreviously. Our results indicate that CEO characteristics are an important factor in explaining CEO...

  8. Characteristics of the Nursing Practice Environment Associated With Lower Unit-Level RN Turnover.

    Science.gov (United States)

    Nelson-Brantley, Heather V; Park, Shin Hye; Bergquist-Beringer, Sandra

    2018-01-01

    The aim of this study is to examine characteristics of the nursing practice environment associated with lower RN turnover. Identifying characteristics of the practice environment that contribute to lower RN turnover is important for meeting the national quality strategy priority of reducing healthcare costs. Data from 1002 adult care units in 162 National Database of Nursing Quality Indicators participating hospitals were analyzed using multivariate linear regression. The Practice Environment Scale of the Nursing Work Index was used to measure practice environment characteristics. RN turnover was measured at the unit level. Nursing units with higher overall ratings of the nursing practice environment had lower rates of RN turnover. Units with higher RN perceived staffing and resource adequacy experienced significantly lower RN turnover. Unit managers and hospital administrators should consider RN perception of staffing and resource adequacy and the overall practice environment when developing targeted strategies for decreasing RN turnover.

  9. The influence of a steroid hormone and of physical exercise on protein metabolism in rats

    International Nuclear Information System (INIS)

    Menschikowski, M.; Jung, K.; Junghans, P.; Petzke, K.J.; Albrecht, V.; Akademie der Wissenschaften der DDR, Potsdam

    1989-01-01

    The influence of an anabolic steroid hormone preparation and of a physical exercise training program was studied on the nitrogen and protein metabolism in rats with the help of the 15 N tracer technique and the emission spectrometric 15 N isotope analysis. For the determination of the dynamic parameters of the protein metabolism graphic (stochastic) and computer-aided compartmental methods wer compared. Using the area method as a stochastic approach the animals showed significant differences in the protein turnover parameters under the influence of hormone treatment and (or) physical stress by swimming exercise in comparison to the controls. (author)

  10. Biodiversity effects on resource use efficiency and community turnover of plankton in Lake Nansihu, China.

    Science.gov (United States)

    Tian, Wang; Zhang, Huayong; Zhang, Jian; Zhao, Lei; Miao, Mingsheng; Huang, Hai

    2017-04-01

    The relationship between biodiversity and ecosystem functioning is a central issue in ecology, especially in aquatic ecosystems due to the ecophysiological characteristics of plankton. Recently, ecologists have obtained conflicting conclusions while analyzing the influence of species diversity on plankton resource use efficiency (RUE) and community turnover. In this study, both phytoplankton and zooplankton communities were investigated seasonally from 2011 to 2013 in Lake Nansihu, a meso-eutrophic and recovering lake in China. The effects of phytoplankton diversity on RUE of phytoplankton (RUE PP ), zooplankton (RUE ZP ), and community turnover were analyzed. Results showed that both phytoplankton species richness and evenness were positively correlated with RUE PP . RUE ZP had a negative relationship with phytoplankton species richness, but a weak unimodal relationship with phytoplankton evenness. Cyanobacteria community had the opposite influence on RUE PP and RUE ZP . Thus, cyanobacteria dominance will benefit RUE PP in eutrophic lakes, but the growth and reproduction of zooplankton are greatly limited. The strong negative relationship between total phosphorus and RUE ZP confirmed these results. Phytoplankton community turnover tended to decrease with increasing phytoplankton evenness, which was consistent with most previous studies. The correlation coefficient between phytoplankton species richness and community turnover was negative, but not significant (p > 0.05). Therefore, phytoplankton community turnover was more sensitive to the variation of evenness than species richness. These results will be helpful in understanding the effects of species diversity on ecosystem functioning in aquatic ecosystems.

  11. The Impact Of Reward System On Employee Turnover Intention A Study On Logistics Industry Of Sri Lanka

    Directory of Open Access Journals (Sweden)

    M.V.S. Mendis

    2017-09-01

    Full Text Available Human capital is a paramount important part of todays business world. For any company to achieve its corporate strategies it is important to have motivated committed workforce within the company. Therefore keep employees satisfy is a necessity for any organization. Otherwise they may leave the company as there are lots of job opportunities remain in this modern business world. This study focus on how reward system of an organization impact on employee turnover intention. This study empirically evaluated five independent variables remuneration cash incentives work life balance supervisor support and employee recognition and their relationship to the turnover intention of non-executives in the logistics industry of Sri Lanka. The sample consists of 97 non-executive staff in the logistics industry of Sri Lanka. The data collection was done by using a self-administrated structured questionnaire. The results indicated that remuneration cash incentives work life balance supervisor support and employee recognition variables were negatively and significantly correlated with turnover intention. And those relationships were strong. Results of regressing the reward system on turnover intention showed that reward system is a powerful predictor of labour turnover in logistics industry of Sri Lanka. The research findings give evidence that better financial and non-financial rewards have strong impact on employee turnover intention. Therefore to reduce employees high intention to leave the company the management needs to develop well balanced reward system in both financial and non-financial aspects.

  12. Endoplasmic reticulum stress and N-glycosylation modulate expression of WFS1 protein

    International Nuclear Information System (INIS)

    Yamaguchi, Suguru; Ishihara, Hisamitsu; Tamura, Akira; Yamada, Takahiro; Takahashi, Rui; Takei, Daisuke; Katagiri, Hideki; Oka, Yoshitomo

    2004-01-01

    Mutations of the WFS1 gene are responsible for two hereditary diseases, Wolfram syndrome and low frequency sensorineural hearing loss. The WFS1 protein is a glycoprotein located in the endoplasmic reticulum (ER) membrane but its function is poorly understood. Herein we show WFS1 mRNA and protein levels in pancreatic islets to be increased with ER-stress inducers, thapsigargin and dithiothreitol. Another ER-stress inducer, the N-glycosylation inhibitor tunicamycin, also raised WFS1 mRNA but not protein levels. Site-directed mutagenesis showed both Asn-663 and Asn-748 to be N-glycosylated in mouse WFS1 protein. The glycosylation-defective WFS1 protein, in which Asn-663 and Asn-748 had been substituted with aspartate, exhibited an increased protein turnover rate. Consistent with this, the WFS1 protein was more rapidly degraded in the presence of tunicamycin. These data indicate that ER-stress and N-glycosylation play important roles in WFS1 expression and stability, and also suggest regulatory roles for this protein in ER-stress induced cell death

  13. Effects of ractopamine and gender on protein turnover in skeletal ...

    African Journals Online (AJOL)

    p2492989

    Ractopamine significantly decreased rates of in vitro protein degradation ... with 140 mg trenbolone acetate and 14 mg estradiol (Component TE-H, Vet Life). ... samples were not used for statistical analysis, and samples collected after 15 and 29 ..... and its interaction with gender for RNA, DNA, and protein concentrations as.

  14. Survey of pay satisfaction, job satisfaction and employee turnover in ...

    African Journals Online (AJOL)

    Survey of pay satisfaction, job satisfaction and employee turnover in selected business organisations in Lagos, Nigeria. ... Global Journal of Social Sciences ... The study was an attempt at investigating the relatedness of pay satisfaction, job satisfaction and employee turnover in business organizations in Lagos Nigeria.

  15. High bone turnover in Irish professional jockeys.

    LENUS (Irish Health Repository)

    Waldron-Lynch, F

    2012-02-01

    SUMMARY: Professional jockeys are routinely exposed to high impact trauma and sustain fractures frequently. We found that jockeys restrict their caloric intake in order to maintain regulation weights, and that bone turnover is high. There are significant health and safety implications for the racing industry. INTRODUCTION: Professional jockeys routinely sustain fractures from high impact falls. Jockeys maintain a low percentage body fat and a low body mass index (BMI) to achieve low weight targets in order to race. We evaluated dietary habits and bone metabolism in jockeys. METHODS: Bone mineral density (BMD) was measured in 27 male jockeys of the 144 jockeys licensed in Ireland. Fourteen (52%) had BMD T score below -1.0, of whom 12 consented to clinical review, nutritional survey, endocrine studies, and bone turnover markers (BTM). BTM were compared to age- and sex-matched controls (n = 16). RESULTS: BMI was 20.6 +\\/- 1.7 kg\\/m(2); previous fracture frequency was 3.2 +\\/- 2.0 per rider. All had normal endocrine axes. The jockeys\\' diet as determined by a 7-day dietary recall was deficient in energy, calcium, and vitamin D intake. Compared with the control group, the jockey group had evidence of increased bone turnover. CONCLUSIONS: A substantial proportion of the professional jockeys in Ireland have low-normal BMD, low BMI, and high bone turnover that may result from weight and dietary restrictions. These factors seem to have a deleterious effect on their bone health and predispose the jockeys to a high fracture risk that should be remediated.

  16. ON THE ORIGIN OF THE HIGH COLUMN DENSITY TURNOVER IN THE H I COLUMN DENSITY DISTRIBUTION

    International Nuclear Information System (INIS)

    Erkal, Denis; Gnedin, Nickolay Y.; Kravtsov, Andrey V.

    2012-01-01

    We study the high column density regime of the H I column density distribution function and argue that there are two distinct features: a turnover at N H I ≈ 10 21 cm –2 , which is present at both z = 0 and z ≈ 3, and a lack of systems above N H I ≈ 10 22 cm –2 at z = 0. Using observations of the column density distribution, we argue that the H I-H 2 transition does not cause the turnover at N H I ≈ 10 21 cm –2 but can plausibly explain the turnover at N H I ∼> 10 22 cm –2 . We compute the H I column density distribution of individual galaxies in the THINGS sample and show that the turnover column density depends only weakly on metallicity. Furthermore, we show that the column density distribution of galaxies, corrected for inclination, is insensitive to the resolution of the H I map or to averaging in radial shells. Our results indicate that the similarity of H I column density distributions at z = 3 and 0 is due to the similarity of the maximum H I surface densities of high-z and low-z disks, set presumably by universal processes that shape properties of the gaseous disks of galaxies. Using fully cosmological simulations, we explore other candidate physical mechanisms that could produce a turnover in the column density distribution. We show that while turbulence within giant molecular clouds cannot affect the damped Lyα column density distribution, stellar feedback can affect it significantly if the feedback is sufficiently effective in removing gas from the central 2-3 kpc of high-redshift galaxies. Finally, we argue that it is meaningful to compare column densities averaged over ∼ kpc scales with those estimated from quasar spectra that probe sub-pc scales due to the steep power spectrum of H I column density fluctuations observed in nearby galaxies.

  17. Protein dynamics during presynaptic complex assembly on individual ssDNA molecules

    OpenAIRE

    Gibb, Bryan; Ye, Ling F.; Kwon, YoungHo; Niu, Hengyao; Sung, Patrick; Greene, Eric C.

    2014-01-01

    Homologous recombination is a conserved pathway for repairing double?stranded breaks, which are processed to yield single?stranded DNA overhangs that serve as platforms for presynaptic complex assembly. Here we use single?molecule imaging to reveal the interplay between Saccharomyce cerevisiae RPA, Rad52, and Rad51 during presynaptic complex assembly. We show that Rad52 binds RPA?ssDNA and suppresses RPA turnover, highlighting an unanticipated regulatory influence on protein dynamics. Rad51 b...

  18. Input-driven versus turnover-driven controls of simulated changes in soil carbon due to land-use change

    Science.gov (United States)

    Nyawira, S. S.; Nabel, J. E. M. S.; Brovkin, V.; Pongratz, J.

    2017-08-01

    Historical changes in soil carbon associated with land-use change (LUC) result mainly from the changes in the quantity of litter inputs to the soil and the turnover of carbon in soils. We use a factor separation technique to assess how the input-driven and turnover-driven controls, as well as their synergies, have contributed to historical changes in soil carbon associated with LUC. We apply this approach to equilibrium simulations of present-day and pre-industrial land use performed using the dynamic global vegetation model JSBACH. Our results show that both the input-driven and turnover-driven changes generally contribute to a gain in soil carbon in afforested regions and a loss in deforested regions. However, in regions where grasslands have been converted to croplands, we find an input-driven loss that is partly offset by a turnover-driven gain, which stems from a decrease in the fire-related carbon losses. Omitting land management through crop and wood harvest substantially reduces the global losses through the input-driven changes. Our study thus suggests that the dominating control of soil carbon losses is via the input-driven changes, which are more directly accessible to human management than the turnover-driven ones.

  19. The fission yeast RNA binding protein Mmi1 regulates meiotic genes by controlling intron specific splicing and polyadenylation coupled RNA turnover.

    Directory of Open Access Journals (Sweden)

    Huei-Mei Chen

    Full Text Available The polyA tails of mRNAs are monitored by the exosome as a quality control mechanism. We find that fission yeast, Schizosaccharomyces pombe, adopts this RNA quality control mechanism to regulate a group of 30 or more meiotic genes at the level of both splicing and RNA turnover. In vegetative cells the RNA binding protein Mmi1 binds to the primary transcripts of these genes. We find the novel motif U(U/C/GAAAC highly over-represented in targets of Mmi1. Mmi1 can specifically regulate the splicing of particular introns in a transcript: it inhibits the splicing of introns that are in the vicinity of putative Mmi1 binding sites, while allowing the splicing of other introns that are far from such sites. In addition, binding of Mmi1, particularly near the 3' end, alters 3' processing to promote extremely long polyA tails of up to a kilobase. The hyperadenylated transcripts are then targeted for degradation by the nuclear exonuclease Rrp6. The nuclear polyA binding protein Pab2 assists this hyperadenylation-mediated RNA decay. Rrp6 also targets other hyperadenylated transcripts, which become hyperadenylated in an unknown, but Mmi1-independent way. Thus, hyperadenylation may be a general signal for RNA degradation. In addition, binding of Mmi1 can affect the efficiency of 3' cleavage. Inactivation of Mmi1 in meiosis allows meiotic expression, through splicing and RNA stabilization, of at least 29 target genes, which are apparently constitutively transcribed.

  20. Nurse turnover in New Zealand: costs and relationships with staffing practises and patient outcomes.

    Science.gov (United States)

    North, Nicola; Leung, William; Ashton, Toni; Rasmussen, Erling; Hughes, Frances; Finlayson, Mary

    2013-04-01

    To determine the rates and costs of nurse turnover, the relationships with staffing practises, and the impacts on outcomes for nurses and patients. In the context of nursing shortages, information on the rates and costs of nursing turnover can improve nursing staff management and quality of care. Quantitative and qualitative data were collected prospectively for 12 months. A re-analysis of these data used descriptive statistics and correlational analysis techniques. The cost per registered nurse turnover represents half an average salary. The highest costs were related to temporary cover, followed by productivity loss. Both are associated with adverse patient events. Flexible management of nursing resources (staffing below budgeted levels and reliance on temporary cover), and a reliance on new graduates and international recruitment to replace nurses who left, contributed to turnover and costs. Nurse turnover is embedded in staffing levels and practises, with costs attributable to both. A culture of turnover was found that is inconsistent with nursing as a knowledge workforce. Nurse managers did not challenge flexible staffing practices and high turnover rates. Information on turnover and costs is needed to develop strategies that retain nurses as knowledge-based workers. © 2012 Blackwell Publishing Ltd.

  1. A human protein interaction network shows conservation of aging processes between human and invertebrate species.

    Directory of Open Access Journals (Sweden)

    Russell Bell

    2009-03-01

    Full Text Available We have mapped a protein interaction network of human homologs of proteins that modify longevity in invertebrate species. This network is derived from a proteome-scale human protein interaction Core Network generated through unbiased high-throughput yeast two-hybrid searches. The longevity network is composed of 175 human homologs of proteins known to confer increased longevity through loss of function in yeast, nematode, or fly, and 2,163 additional human proteins that interact with these homologs. Overall, the network consists of 3,271 binary interactions among 2,338 unique proteins. A comparison of the average node degree of the human longevity homologs with random sets of proteins in the Core Network indicates that human homologs of longevity proteins are highly connected hubs with a mean node degree of 18.8 partners. Shortest path length analysis shows that proteins in this network are significantly more connected than would be expected by chance. To examine the relationship of this network to human aging phenotypes, we compared the genes encoding longevity network proteins to genes known to be changed transcriptionally during aging in human muscle. In the case of both the longevity protein homologs and their interactors, we observed enrichments for differentially expressed genes in the network. To determine whether homologs of human longevity interacting proteins can modulate life span in invertebrates, homologs of 18 human FRAP1 interacting proteins showing significant changes in human aging muscle were tested for effects on nematode life span using RNAi. Of 18 genes tested, 33% extended life span when knocked-down in Caenorhabditis elegans. These observations indicate that a broad class of longevity genes identified in invertebrate models of aging have relevance to human aging. They also indicate that the longevity protein interaction network presented here is enriched for novel conserved longevity proteins.

  2. Cysteine proteinases regulate chloroplast protein content and composition in tobacco leaves: a model for dynamic interactions with ribulose-1,5-bisphosphate carboxylase/oxygenase (Rubisco) vesicular bodies.

    Science.gov (United States)

    Prins, Anneke; van Heerden, Philippus D R; Olmos, Enrique; Kunert, Karl J; Foyer, Christine H

    2008-01-01

    The roles of cysteine proteinases (CP) in leaf protein accumulation and composition were investigated in transgenic tobacco (Nicotiana tabacum L.) plants expressing the rice cystatin, OC-1. The OC-1 protein was present in the cytosol, chloroplasts, and vacuole of the leaves of OC-1 expressing (OCE) plants. Changes in leaf protein composition and turnover caused by OC-1-dependent inhibition of CP activity were assessed in 8-week-old plants using proteomic analysis. Seven hundred and sixty-five soluble proteins were detected in the controls compared to 860 proteins in the OCE leaves. A cyclophilin, a histone, a peptidyl-prolyl cis-trans isomerase, and two ribulose-1,5-bisphosphate carboxylase/oxygenase (Rubisco) activase isoforms were markedly altered in abundance in the OCE leaves. The senescence-related decline in photosynthesis and Rubisco activity was delayed in the OCE leaves. Similarly, OCE leaves maintained higher leaf Rubisco activities and protein than controls following dark chilling. Immunogold labelling studies with specific antibodies showed that Rubisco was present in Rubisco vesicular bodies (RVB) as well as in the chloroplasts of leaves from 8-week-old control and OCE plants. Western blot analysis of plants at 14 weeks after both genotypes had flowered revealed large increases in the amount of Rubisco protein in the OCE leaves compared to controls. These results demonstrate that CPs are involved in Rubisco turnover in leaves under optimal and stress conditions and that extra-plastidic RVB bodies are present even in young source leaves. Furthermore, these data form the basis for a new model of Rubisco protein turnover involving CPs and RVBs.

  3. Biochemical relationships between bone turnover markers and blood glucose in patients with type 2 diabetes mellitus.

    Science.gov (United States)

    Hussein, Rasha M

    2017-11-01

    Patients with type 2 diabetes mellitus develop many complications including osteopenia, which is associated with high fracture risk. Osteocalcin is a non collagenous protein derived from the osteoblasts. Recently, it was found that osteocalcin enhances the pancreatic beta cell proliferation, insulin secretion and protection against type 2 diabetes. Investigation of the association of serum osteocalcin and other bone turnover markers with blood glucose level and diabetes mellitus duration in type 2 diabetic patients. Twenty diagnosed type 2 diabetic patients together with 20 healthy controls were enrolled in this study. Serum osteocalcin, alkaline phosphatase activity and calcium concentrations were measured by commercial ELISA kits. The results showed that type 2 diabetic patients exhibited a significantly lower serum osteocalcin and calcium (p=0.0001 and 0.002 respectively) and a higher alkaline phosphatase (p=0.008) compared to the controls. Multiple linear regression analysis revealed that serum osteocalcin was inversely associated with fasting blood glucose and Diabetes Mellitus duration (β=- 0.018; p=0.007 and β=- 0.085; p=0.014 respectively) in Type 2 diabetic patients. In addition, alkaline phosphatase was positively associated (β=0.828; p=0.015) while serum calcium was negatively associated (β=- 0.046; p=0.048) with Diabetes Mellitus duration. These results refer to the strong association between diabetes and bone turnover markers and call for monitoring of diabetes-associated osteopenia in type 2 diabetic patients. Copyright © 2017 Diabetes India. Published by Elsevier Ltd. All rights reserved.

  4. Intrinsically Disordered Segments Affect Protein Half-Life in the Cell and during Evolution

    NARCIS (Netherlands)

    Lee, R.T.J.G. van der; Lang, B.; Kruse, K.; Gsponer, J.; Groot, N.; Huynen, M.A.; Matouschek, A.; Fuxreiter, M.; Babu, M.M.

    2014-01-01

    Precise control of protein turnover is essential for cellular homeostasis. The ubiquitin-proteasome system is well established as a major regulator of protein degradation, but an understanding of how inherent structural features influence the lifetimes of proteins is lacking. We report that yeast,

  5. Application of two neural network paradigms to the study of voluntary employee turnover.

    Science.gov (United States)

    Somers, M J

    1999-04-01

    Two neural network paradigms--multilayer perceptron and learning vector quantization--were used to study voluntary employee turnover with a sample of 577 hospital employees. The objectives of the study were twofold. The 1st was to assess whether neural computing techniques offered greater predictive accuracy than did conventional turnover methodologies. The 2nd was to explore whether computer models of turnover based on neural network technologies offered new insights into turnover processes. When compared with logistic regression analysis, both neural network paradigms provided considerably more accurate predictions of turnover behavior, particularly with respect to the correct classification of leavers. In addition, these neural network paradigms captured nonlinear relationships that are relevant for theory development. Results are discussed in terms of their implications for future research.

  6. The Link between Training Satisfaction, Work Engagement and Turnover Intention

    Science.gov (United States)

    Memon, Mumtaz Ali; Salleh, Rohani; Baharom, Mohamed Noor Rosli

    2016-01-01

    Purpose: The purpose of this paper is to examine the casual relationship between training satisfaction, work engagement (WE) and turnover intention and the mediating role of WE between training satisfaction and turnover intention. Design/methodology/approach: Data were collected from 409 oil and gas professionals using an email survey…

  7. Flexible work arrangements, job satisfaction, and turnover intentions: the mediating role of work-to-family enrichment.

    Science.gov (United States)

    McNall, Laurel A; Masuda, Aline D; Nicklin, Jessica M

    2010-01-01

    The authors examined the relation between the availability of 2 popular types of flexible work arrangements (i.e., flextime and compressed workweek) and work-to-family enrichment and, in turn, the relation between work-to-family enrichment and (a) job satisfaction and (b) turnover intentions. In a sample of 220 employed working adults, hierarchical regression analyses showed that work-to-family enrichment mediated the relation between flexible work arrangements and both job satisfaction and turnover intentions, even after controlling for gender, age, marital status, education, number of children, and hours worked. Thus, the availability of flexible work arrangements such as flextime and compressed workweek seems to help employees experience greater enrichment from work to home, which, in turn, is associated with higher job satisfaction and lower turnover intentions. The authors discuss the implications for research and practice.

  8. Correlation of cell growth and heterologous protein production by Saccharomyces cerevisiae

    DEFF Research Database (Denmark)

    Liu, Zihe; Hou, Jin; Martinez Ruiz, José Luis

    2013-01-01

    .g., metabolic and cellular stresses have a strong impact on recombinant protein production. In this work, we investigated the effect of the specific growth rate on the production of two different recombinant proteins. Our results show that human insulin precursor is produced in a growth-associated manner...... turnover, cell cycle, and global stress response. We also found that there is a shift at a specific growth rate of 0.1 h−1 that influences protein production. Thus, for lower specific growth rates, the α-amylase and insulin precursor-producing strains present similar cell responses and phenotypes, whereas......With the increasing demand for biopharmaceutical proteins and industrial enzymes, it is necessary to optimize the production by microbial fermentation or cell cultures. Yeasts are well established for the production of a wide range of recombinant proteins, but there are also some limitations; e...

  9. Underestimation of glucose turnover corrected with high-performance liquid chromatography purification of [6-3H]glucose

    International Nuclear Information System (INIS)

    Schwenk, W.F.; Butler, P.C.; Haymond, M.W.; Rizza, R.A.

    1990-01-01

    We have recently reported that during infusion of commercially available [6-3H]glucose, a radioactive nonglucose contaminant may accumulate in plasma causing errors in the measurement of glucose turnover. To determine whether purification of this tracer by HPLC (high-performance liquid chromatography) before infusion would eliminate the contaminant in plasma and remove the underestimation of glucose turnover reported during hyperinsulinemia, four normal subjects each underwent two 5-h euglycemic clamps during infusion of insulin (1 mU.kg-1.min-1). Glucose turnover was measured with either commercially available [6-3H]glucose or with HPLC-purified [6-3H]glucose. HPLC analysis of samples from the clamps done with commercially available [6-3H]glucose showed that 9.7% of the infused tracer and 26% of the plasma glucose 3H radioactivity were contaminants. In contrast, no contaminant was observed in the plasma during infusion of HPLC-purified [6-3H]glucose. During the last hour of the clamp, mean glucose turnover using commercially available [6-3H]glucose was less (P less than 0.01) than the mean glucose infusion rate (7.6 +/- 0.3 vs. 10.5 +/- 0.3 mg.kg-1.min-1) yielding apparent negative (P less than 0.001) hepatic glucose release. In contrast, when HPLC-purified [6-3H]glucose was employed, glucose turnover equaled the glucose infusion rate (10.4 +/- 0.9 vs. 10.2 +/- 0.9 mg.kg-1.min-1) and hepatic glucose release was no longer negative. We conclude that removal of a tritiated nonglucose contaminant in [6-3H]glucose by HPLC yields correct estimations of glucose turnover at steady state

  10. The curvilinear effect of work engagement on employees' turnover intentions.

    Science.gov (United States)

    Caesens, Gaëtane; Stinglhamber, Florence; Marmier, Virginie

    2016-04-01

    Numerous studies have shown the positive consequences of work engagement for both organisations and employees experiencing it. For instance, research has demonstrated that work-engaged employees have lower levels of turnover intentions than non-engaged employees. However, in this research, we examined whether there is a dark side of work engagement. More precisely, we investigated whether the relationship between work engagement and employees' turnover intentions might be non-linear. Based on two different samples, our results indicated that the relationship between work engagement and employees' turnover intentions is curvilinear. The theoretical and practical implications of these results are discussed. © 2014 International Union of Psychological Science.

  11. Efficacy of 22Na turnover in ecopbysiological studies of carnivores

    African Journals Online (AJOL)

    Efficacy of 22Na turnover in ecopbysiological studies of carnivores. loS. Wilkinson and J.D. Skinner*. Mammal Research Institute, University of Pretoria, Pretoria, 0002 Republic of South Africa. Received 8 December 1986; accepted 11 August 1987. 22Na turnover rates gave overestimates of mean 23Na intake in both ...

  12. Employee turnover: measuring the malady.

    Science.gov (United States)

    O'Connor, Stephen

    2002-01-01

    One measure of an organization's value to its employees is turnover. But how do you know if your employees are wondering if the grass is greener elsewhere? Scott Badler in his book What's So Funny about Looking for a Job? suggests a quick quiz to find out.

  13. Work engagement, burnout and related constructs as predictors of turnover intentions

    Directory of Open Access Journals (Sweden)

    Janine du Plooy

    2010-12-01

    Research purpose: The main purpose of the study was to determine whether work engagement, burnout, organisational citizenship behaviour (OCB and work alienation are predictors of turnover intentions. Motivation for the study: Organisations operating within the 21st century face significant challenges in the management of talent and human capital. One in particular is voluntary employee turnover and the lack of appropriate business models to track this process. Research design, approach and method: A secondary data analysis (SDA was performed in a quantitative research tradition on the cross-sectional survey data collected from a large South African Information and Communication Technologies (ICT sector company (n = 2429. Main findings: The results of the study confirmed the predictive model (work engagement, burnout, OCB and work alienation of turnover intention. Specifically, work engagement and OCBs were significantly negatively related to turnover intention; whilst burnout and work alienation were significantly positively related to turnover intention. Several third-variable relationships, such as biographic and demographic variables, indicated statistical significance. Practical/managerial implications: Practical implications of the study could impact on human resource (HR value-chain activities in the form of evidence-based and improved recruitment and selection procedures, employee retention strategies and training and development interventions. Issues concerning talent management could also be addressed. Contribution/value-add: The study described in this article took Industrial/Organisational (I/O psychological concepts and linked them in unique combinations to establish better predictive validity of a new turnover intentions model.

  14. Predictors of actual turnover in a national sample of newly licensed registered nurses employed in hospitals.

    Science.gov (United States)

    Brewer, Carol S; Kovner, Christine T; Greene, William; Tukov-Shuser, Magdalene; Djukic, Maja

    2012-03-01

    This paper is a report of a study of factors that affect turnover of newly licensed registered nurses in United States hospitals. There is a large body of research related to nursing retention; however, there is little information specific to newly licensed registered nurse turnover. Incidence rates of turnover among new nurses are unknown because most turnover data are not from nationally representative samples of nurses. This study used a longitudinal panel design to obtain data from 1653 registered nurses who were recently licensed by examination for the first time. We mailed surveys to a nationally representative sample of hospital registered nurses 1 year apart. The analytic sample consisted of 1653 nurses who responded to both survey mailings in January of 2006 and 2007. Full-time employment and more sprains and strains (including back injuries) result in more turnover. Higher intent to stay and hours of voluntary overtime and more than one job for pay reduces turnover. When we omitted intent to stay from the probit model, less job satisfaction and organizational commitment led to more turnover, confirming their importance to turnover. Magnet Recognition Award(®) hospitals and several other work attributes had no effect on turnover.   Turnover problems are complex, which means that there is no one solution to decreasing turnover. Multiple points of intervention exist. One specific approach that may improve turnover rates is hospital policies that reduce strains and sprains. © 2011 The Authors. Journal of Advanced Nursing © 2011 Blackwell Publishing Ltd.

  15. Dynamics of Hippocampal Protein Expression During Long-term Spatial Memory Formation*

    Science.gov (United States)

    Borovok, Natalia; Nesher, Elimelech; Levin, Yishai; Reichenstein, Michal; Pinhasov, Albert

    2016-01-01

    Spatial memory depends on the hippocampus, which is particularly vulnerable to aging. This vulnerability has implications for the impairment of navigation capacities in older people, who may show a marked drop in performance of spatial tasks with advancing age. Contemporary understanding of long-term memory formation relies on molecular mechanisms underlying long-term synaptic plasticity. With memory acquisition, activity-dependent changes occurring in synapses initiate multiple signal transduction pathways enhancing protein turnover. This enhancement facilitates de novo synthesis of plasticity related proteins, crucial factors for establishing persistent long-term synaptic plasticity and forming memory engrams. Extensive studies have been performed to elucidate molecular mechanisms of memory traces formation; however, the identity of plasticity related proteins is still evasive. In this study, we investigated protein turnover in mouse hippocampus during long-term spatial memory formation using the reference memory version of radial arm maze (RAM) paradigm. We identified 1592 proteins, which exhibited a complex picture of expression changes during spatial memory formation. Variable linear decomposition reduced significantly data dimensionality and enriched three principal factors responsible for variance of memory-related protein levels at (1) the initial phase of memory acquisition (165 proteins), (2) during the steep learning improvement (148 proteins), and (3) the final phase of the learning curve (123 proteins). Gene ontology and signaling pathways analysis revealed a clear correlation between memory improvement and learning phase-curbed expression profiles of proteins belonging to specific functional categories. We found differential enrichment of (1) neurotrophic factors signaling pathways, proteins regulating synaptic transmission, and actin microfilament during the first day of the learning curve; (2) transcription and translation machinery, protein

  16. Dynamics of Hippocampal Protein Expression During Long-term Spatial Memory Formation.

    Science.gov (United States)

    Borovok, Natalia; Nesher, Elimelech; Levin, Yishai; Reichenstein, Michal; Pinhasov, Albert; Michaelevski, Izhak

    2016-02-01

    Spatial memory depends on the hippocampus, which is particularly vulnerable to aging. This vulnerability has implications for the impairment of navigation capacities in older people, who may show a marked drop in performance of spatial tasks with advancing age. Contemporary understanding of long-term memory formation relies on molecular mechanisms underlying long-term synaptic plasticity. With memory acquisition, activity-dependent changes occurring in synapses initiate multiple signal transduction pathways enhancing protein turnover. This enhancement facilitates de novo synthesis of plasticity related proteins, crucial factors for establishing persistent long-term synaptic plasticity and forming memory engrams. Extensive studies have been performed to elucidate molecular mechanisms of memory traces formation; however, the identity of plasticity related proteins is still evasive. In this study, we investigated protein turnover in mouse hippocampus during long-term spatial memory formation using the reference memory version of radial arm maze (RAM) paradigm. We identified 1592 proteins, which exhibited a complex picture of expression changes during spatial memory formation. Variable linear decomposition reduced significantly data dimensionality and enriched three principal factors responsible for variance of memory-related protein levels at (1) the initial phase of memory acquisition (165 proteins), (2) during the steep learning improvement (148 proteins), and (3) the final phase of the learning curve (123 proteins). Gene ontology and signaling pathways analysis revealed a clear correlation between memory improvement and learning phase-curbed expression profiles of proteins belonging to specific functional categories. We found differential enrichment of (1) neurotrophic factors signaling pathways, proteins regulating synaptic transmission, and actin microfilament during the first day of the learning curve; (2) transcription and translation machinery, protein

  17. What does nurse turnover rate mean and what is the rate?

    Science.gov (United States)

    Kovner, Christine T; Brewer, Carol S; Fatehi, Farida; Jun, Jin

    2014-01-01

    Registered nurse turnover is an important indicator of the nurse job market. Despite its wide use as a measure for health-care system analysis, there is a lack of consistency in the definition of turnover. Some definitions include any nurse leaving an organization; others may include involuntary and voluntary leaving. These inconsistent definitions also result in various turnover rates. The RN Work Project is a 10-year panel study of new nurses. Data were collected from the new nurses, rather than from a specific organization. About 17.5% of new nurses leave their first job within 1 year of starting their jobs. Consistent and accurate measurement of turnover is an important step in addressing organizational work environments and policies about the nursing workforce. © The Author(s) 2014 Reprints and permissions: sagepub.co.uk/journalsPermissions.nav.

  18. The mediating role of job satisfaction between leader-member exchange and turnover intentions.

    Science.gov (United States)

    Han, Guohong Helen; Jekel, Marc

    2011-01-01

    The aim of the present study was to investigate whether job satisfaction mediates between leader-member exchange and nurse turnover intentions. Limited knowledge is available on the mediating role of job satisfaction between leader-member exchange and turnover intentions in the nursing field. This is a cross-sectional survey study. Data were collected in a US hospital. Higher leader-member exchange was associated with lower turnover intentions (β=-0.41, PLeader-member exchange was positively related to one's job satisfaction (β=0.50, Pleader-member exchange and job satisfaction were both controlled for, the link between leader-member exchange and turnover intentions was no longer significant (β=-0.12, P>0.05). Job satisfaction mediates the link between leader-member exchange and turnover intentions. The present study reinforces the significant role of managers. Nurse managers can try to cultivate a good relationship with the nurses. This can enhance nurses' job satisfaction and in turn lower their turnover intentions. © 2010 The Authors. Journal compilation © 2010 Blackwell Publishing Ltd.

  19. Turnover of radio-iodinated and biosynthetically labelled fibrinogen in rhesus monkeys

    International Nuclear Information System (INIS)

    Moza, A.K.

    1982-01-01

    Successful radio-iodination of monkey fibrinogen using a previously documented method for rabbit fibrinogen is reported. The label was securely bound to fibrinogen without any evidence of polymerisation. Turnover rates and other kinetic parameters of fibrinogen using 125 I-fibrinogen have been compared with those obtained with biosynthetically labelled donor 75 Se-fibrinogen. Both studies yielded identical results. The values for normal monkeys showed a half life of 43.8 +- 1.03 h with 125 I-fibrinogen and 47.15 +- 1.24 with 75 Se-fibrinogen. The turnover rate of endogenous 75 Se-fibrinogen following administration of 75 Se-selenomethionine has also been studied. The half disappearance time value of 100.34 h was much longer than the t1/2 values obtained with either 125 I or 75 Se-fibrinogen. This is believed to be due the staggered input of fibrinogen molecules from the liver. (author)

  20. Proteins interacting with the 26S proteasome

    DEFF Research Database (Denmark)

    Hartmann-Petersen, R; Gordon, C

    2004-01-01

    The 26S proteasome is the multi-protein protease that recognizes and degrades ubiquitinylated substrates targeted for destruction by the ubiquitin pathway. In addition to the well-documented subunit organization of the 26S holoenzyme, it is clear that a number of other proteins transiently...... associate with the 26S complex. These transiently associated proteins confer a number of different roles such as substrate presentation, cleavage of the multi-ubiquitin chain from the protein substrate and turnover of misfolded proteins. Such activities are essential for the 26S proteasome to efficiently...... fulfill its intracellular function in protein degradation....

  1. Employee motivation development opportunities seeking to reduce employee turnover

    OpenAIRE

    Pilukienė, Laura; Kšivickaitė, Gertūda

    2014-01-01

    In this article, the authors analyse one of the main nowadays human resources problem – growing employee turnover. Employee motivation process is analysed as a key competitive advantage in employee retention that leads to the growth of the business company’s productivity and competitive stability. The main goal of the article is to analyse the employee motivation and employee turnover relationship and its development possibilities in Lithuania’s business sector.

  2. An empirical note on job turnover and internal mobility of workers

    OpenAIRE

    Hassink, W.H.J.

    1995-01-01

    I find that large firms have a higher rate of job turnover in which internal mobility of workers is involved. These firms are able to reduce turnover costs, by making use of their ability to attain a higher internal mobility rate.

  3. Age-related collagen turnover of the interstitial matrix and basement membrane: Implications of age- and sex-dependent remodeling of the extracellular matrix.

    Science.gov (United States)

    Kehlet, Stephanie N; Willumsen, Nicholas; Armbrecht, Gabriele; Dietzel, Roswitha; Brix, Susanne; Henriksen, Kim; Karsdal, Morten A

    2018-01-01

    The extracellular matrix (ECM) plays a vital role in maintaining normal tissue function. Collagens are major components of the ECM and there is a tight equilibrium between degradation and formation of these proteins ensuring tissue health and homeostasis. As a consequence of tissue turnover, small collagen fragments are released into the circulation, which act as important biomarkers in the study of certain tissue-related remodeling factors in health and disease. The aim of this study was to establish an age-related collagen turnover profile of the main collagens of the interstitial matrix (type I and III collagen) and basement membrane (type IV collagen) in healthy men and women. By using well-characterized competitive ELISA-assays, we assessed specific fragments of degraded (C1M, C3M, C4M) and formed (PINP, Pro-C3, P4NP7S) type I, III and IV collagen in serum from 617 healthy men and women ranging in ages from 22 to 86. Subjects were divided into 5-year age groups according to their sex and age. Groups were compared using Kruskal-Wallis adjusted for Dunn's multiple comparisons test and Mann-Whitney t-test. Age-specific changes in collagen turnover was most profound for type I collagen. PINP levels decreased in men with advancing age, whereas in women, the level decreased in early adulthood followed by an increase around the age of menopause (age 40-60). Sex-specific changes in type I, III and IV collagen turnover was present at the age around menopause (age 40-60) with women having an increased turnover. In summary, collagen turnover is affected by age and sex with the interstitial matrix and the basement membrane being differently regulated. The observed changes needs to be accounted for when measuring ECM related biomarkers in clinical studies.

  4. Norepinephrine metabolism in man using deuterium labeling: turnover 4-hydroxy-3-methoxymandelic acid

    Energy Technology Data Exchange (ETDEWEB)

    Mardh, G.; Sjoequist, B.; Anggard, E.

    1982-06-01

    4-Hydroxy-3-methoxymandelic acid (HMMA; VMA) labeled with three deuterium atoms was used to study the turnover and fate of HMMA following intravenous injection. Five healthy men were given a pulse dose of 5.0 mumol of labeled HMMA. Plasma and urinary levels of both endogenous and labeled HMMA were subsequently followed by gas chromatography-mass spectrometry using selected ion detection. The kinetic parameters were determined both with and without compensation for the pool expansion caused by the injection of labeled HMMA. The urinary recovery of labeled HMMA was 85 +/- 10% (mean +/- SD). No conversion of HMMA to 4-hydroxy-3-methoxyphenyl glycol (HMPG) occurred. The biological half-life of HMMA was 0.54 +/- 0.22 h. The apparent volume of distribution was 0.36 +/- 0.11 L/kg. The production rate or body turnover was 1.27 +/- 0.51 mumol HMMA/h and urinary excretion rate was 0.82 +/- 0.22 mumol/h. These results show that HMMA is turnover over rapidly in a relatively small volume of distribution and that, unlike HMPG, it is an end metabolite of norepinephrine in man.

  5. The perceived stress and turnover intention of direct-care staff of community residential facilities

    OpenAIRE

    Lightle, Kevin Eugene

    1990-01-01

    This study examines turnover among direct-care staff of community residential facilities. Turnover is of concern as the projected rate indicated by direct-care staff is 34%. A review of personnel records project an annual turnover rate of 40%. Stress is examined for its relationship to turnover. The Maslach Burnout Inventory is used to measure the perceived stress level of staff. Results indicate direct-care staff are not stressed to the point of burnout in two of ...

  6. Whole body and tissue cholesterol turnover in the baboon

    International Nuclear Information System (INIS)

    Dell, R.B.; Mott, G.E.; Jackson, E.M.; Ramakrishnan, R.; Carey, K.D.; McGill, H.C. Jr.; Goodman, D.S.

    1985-01-01

    Cholesterol turnover was studied in four baboons by injecting [ 14 C]cholesterol 186 days and [ 3 H]cholesterol 4 days before necropsy, and fitting a two- or three-pool model to the resulting specific activity-time data. At necropsy, cholesterol mass and specific activity were determined for the total body and for many tissues. The principal aim of this study was to estimate the extent of cholesterol synthesis in the side pools of the model, by computing the amount of side pool synthesis needed to equal the measured total body cholesterol. Central pool synthesis varied from 61 to 89% of the total cholesterol production rate. Moreover, the finding that the measured total body cholesterol fell within the range obtained from the kinetic analysis by using reasonable assumptions, provides evidence for the physiological validity of the model. A second aim of this study was to explore cholesterol turnover in various tissues. A pool model predicts that rapidly turning over tissues will have higher specific activities at early times and lower specific activities at later times after injection of tracer relative to slowly turning over tissues, except where significant synthesis occurs. Results in all four baboons were similar. Turnover rates for the different tissues loosely fell into three groups which were turning over at fast, intermediate, and slow rates. Finally, the magnitude of variation of cholesterol specific activity was moderate for several distributed tissues (fat, muscle, arteries, and the alimentary tract), but was small for liver. Cholesterol turnover in serial biopsies of skin, muscle, and fat could, however, be fitted with a single pool to estimate tissue turnover rates

  7. Turnover of nursing employees in a Gauteng hospital group

    Directory of Open Access Journals (Sweden)

    Japie Greyling

    2010-11-01

    Research purpose: The purpose of this study was to investigate individual determinants of voluntary turnover to identify a risk-group profile. Motivation for the study: Nursing employers should have a clearer understanding of the dynamics around nurses’ turnover behaviour and embark on strategies to retain their talent. Research design, approach and method: A survey measuring voluntary turnover was conducted among 262 professional and assistant nurses in three selected hospitals in Gauteng province using the McCarthy, Tyrrell and Cronin (2002 instrument. Pearson’s chi square with Yates’s continuity correction tested the relationship among the variables presented in a contingency table, in other words the risk group and each of the individual determinants. Main findings: Discontent with salaries was the major determinant of the nurses’ resignation. Organisational causes were nursing practices, the work environment, physical-emotional costs and employment opportunities after resignation. Practical/managerial implications: Hospital management could indeed establish a good rapport with nursing staff while facilitating respectful and ethical conduct by doctors towards nursing staff. Putting into place effective labour practices and business strategies could improve job satisfaction in the workplace. Contribution/value-add: This study contributed to a greater understanding of the personal and organisational determinants of the turnover of nurses in South African hospitals.

  8. Adeprene influence on the turnover rate of brain noradrenaline

    International Nuclear Information System (INIS)

    Tyutyulkova, N.I.; Gorancheva, J.I.; Ankov, V.K.

    1978-01-01

    The influence of Adeprene - Bulgarian antidepressant - on the content and the turnover rate of the rat brain noradrenaline was studied. The animals were injected intraperitoneally during 5 days with 20 mg/kg Adeprene. One hour after the last administration of Adeprene, Tyrosine, labelled with 14 C was injected. The animals were sacrified on the 1st, 2nd and 4th hours after the injection of 14 C-Tyrosine. The tyrosine and noradrenaline concentration were determined spectrofluorimetrically the concentration of the compounds labelled with 14 C by means of a liquid scintillator. The turnover rate constant of noradrenaline was calculated on the basis of the obtained results and the respective formula. It was established that under the influence of Adeprene, the noradrenaline concentration in the brain rises from 0,5 g/g in the control animals to 0,6 in treated mice. The turnover rate constant of noradrenaline, however, drops to 0,9 g/g/hour as compared to 0,15 g/g/hours in the controls. The determination of the turnover rate provides an idea about the intensity of utilization and synthesis of the mediator and is considered consequently as a more radiosensitive index for the neuronal activity then the total amine content. (A.B.)

  9. Carbon Turnover during Effluent Application to the Land: A Potential Role for Vegetation?

    Directory of Open Access Journals (Sweden)

    Vasileios A. Tzanakakis

    2015-01-01

    Full Text Available This work investigates the effect of plant species (Eucalyptus camaldulensis vs. Arundo donax on carbon (C turnover during wastewater application to the land. The study was carried out in 40-liter pots under field conditions and plant species were treated either with pre-treated municipal wastewater or freshwater. Plant species had a strong effect on soil organic matter with pots planted with E. camaldulensis showing greater values than pots planted with A. donax. In accordance, greater respiration rates were measured in E. camaldulensis pots compared to those planted with A. donax. The respiration rate followed a decreasing trend with the progress of the season for both species. These findings suggest differences in soil microbial community composition and/or activity in the rhizosphere of plant species. Minor effects of plant species or effluent were observed in dissolved organic carbon, protein, and hexoses content. In conclusion, the results of the present study reveal an important role of plant species on C cycling in terrestrial environments with potential implications on the sequestration of C and release of nutrients and pollutants.

  10. An empirical not on job turnover and internal mobility of workers

    NARCIS (Netherlands)

    Hassink, W.H.J.

    1996-01-01

    The rate of job turnover in which the internal mobility of workers is involved is higher in large firms than in small firms. Large firms are able to reduce turnover costs by using their ability to attain a higher internal mobility rate.

  11. Radioimmunoassay of human eosinophil cationic protein

    International Nuclear Information System (INIS)

    Venge, P.; Roxin, L.E.; Olsson, I.

    1977-01-01

    A radioimmunosorbent assay has been developed which allows the detection in serum of a cationic protein derived from eosinophil granulocytes. In 34 healthy individuals the mean level was 31 μg/l. with a range of 5 to 55 μg/l. The serum concentration of 'eosinophil' cationic protein was correlated (P<0.001) to the number of eosinophil granulocytes in peripheral blood. Quantitiation of 'eosinophil' cationic protein in serum might be useful in the study of eosinophil granulocyte turnover and function in vivo. (author)

  12. Gingival crevicular fluid bone turnover biomarkers: How postmenopausal women respond to orthodontic activation.

    Science.gov (United States)

    Smuthkochorn, Sorapan; Palomo, J Martin; Hans, Mark G; Jones, Corey S; Palomo, Leena

    2017-07-01

    Bone turnover associated with orthodontic tooth movement is evidenced by increased bone turnover markers in gingival crevicular fluid (GCF). Postmenopausal women have an increased concentration of serum bone turnover markers. The filtrate of this serum makes up GCF, but little is known of the bone turnover around teeth in this cohort. The objective of this investigation was to compare the GCF bone turnover markers in premenopausal vs postmenopausal women receiving orthodontic treatment at baseline and at orthodontic activation. Twenty-eight women were enrolled in the study and separated into 2 groups: premenopausal (16) and postmenopausal (12). Bone turnover was evaluated by GCF at baseline and 24 hours after orthodontic appliance activation. GCF concentrations of RANKL and OPN were measured using ELISA. Baseline and change in concentrations were compared between groups. Baseline RANKL and OPN were significantly different between the premenopausal and postmenopausal groups (P orthodontic appliance activation in both groups (P orthodontic activation was not significantly different between groups. Although postmenopausal women have a different bone turnover profile at baseline than do their premenopausal counterparts, there is no difference in their response to orthodontic activation. This confers a level of security associated with orthodontic activation. Future studies are warranted to construct biomarker curves throughout orthodontic therapy. Copyright © 2017 American Association of Orthodontists. Published by Elsevier Inc. All rights reserved.

  13. The relationship between clinician turnover and adolescent treatment outcomes: An examination from the client perspective

    Science.gov (United States)

    Garner, Bryan R.; Funk, Rodney R.; Hunter, Brooke D.

    2012-01-01

    The turnover of substance use disorder (SUD) treatment staff has been assumed to adversely impact treatment effectiveness, yet only limited research has empirically examined this assumption. Representing an extension of prior organizational-level analyses of the impact of staff turnover on client outcomes, this study examined the impact of SUD clinician turnover on adolescent treatment outcomes using a client perspective. Multilevel regression analysis did reveal that relative to those adolescents who did not experience clinician turnover, adolescents who experienced both direct and indirect clinician turnover reported a significantly higher percentage of days using alcohol or drugs at 6-month follow-up. However, clinician turnover was not found to have significant associations (negative or positive) with the other five treatment outcomes examined (e.g., substance-related problems, involvement in illegal activity). Thus, consistent with our prior findings, the current study provides additional evidence that turnover of SUD clinicians is not necessarily associated with adverse treatment outcomes. PMID:23083980

  14. Revisiting the impact of job satisfaction and organizational commitment on nurse turnover intention: an individual differences analysis.

    Science.gov (United States)

    De Gieter, Sara; Hofmans, Joeri; Pepermans, Roland

    2011-12-01

    Nurse turnover is an important contributing factor to the worldwide nursing shortage. Many studies have examined the antecedents of nurse turnover to gain a better understanding of the problem and help hospitals reduce their turnover rates. However, an important shortcoming of this research stream is its exclusive focus on explaining turnover behavior of the "average nurse", thereby disregarding individual differences between nurses and groups of nurses. To examine individual differences in the relationships between two crucial turnover antecedents - job satisfaction and organizational commitment - and nurse turnover intention. A sample of 287 nurses working for a variety of Belgian hospitals participated in the study. A survey method was used to collect quantitative data, which were analyzed through standard multiple linear regression, mixture regression models and t-tests. In the total sample of hospital nurses, both job satisfaction and organizational commitment significantly predicted nurse turnover intention. However, subsequent individual differences analyses revealed the existence of two subgroups of nurses. In the satisfaction focused group, only job satisfaction was found to predict nurse turnover intention, whereas in the satisfaction and commitment focused group both job satisfaction and organizational commitment were related to turnover intention. Furthermore, nurses in the latter group displayed stronger turnover intention, were significantly younger and had less job tenure and organizational tenure than nurses in the satisfaction focused group. The debate on the antecedents of nurse turnover still continues, as the existing models fail to fully grasp nurse turnover. The present study identifies individual differences in nurse turnover antecedents among groups of nurses as a possible reason for the absence of one comprehensive turnover model that holds for the general nursing population. Further studies are needed in order to capture the total impact

  15. Does value congruence between nurses and supervisors effect job satisfaction and turnover?

    Science.gov (United States)

    Hunt, Deborah

    2014-07-01

    The purpose of this study was to examine the relationship of congruency of leadership support and value of patient outcomes between nurses and nurse managers and nurses' job satisfaction and turnover intent. Turnover most often has a negative effect on an organization. Leadership support and patient outcomes have been identified as important factors, but congruency has not been studied in great detail. This quantitative non-experimental study included registered nurses (92) and nurse managers (21) in five non-magnet hospitals in the United States. Value congruence on leadership support was correlated with job satisfaction: Satisfaction in Nursing Scale (SINs)-Workload Barriers (r = 0.327, Administrative Support r = 0.544 and Collegiality = 0.920, P congruence and leadership support (Leadership Practices Inventory, LPI) was negatively correlated with turnover intent (r = 0.317, P 0.05) was noted. Value congruence of leadership support is related to job satisfaction and may be a factor in turnover intent. Nurse Administrators can use these results to develop policies to address the turnover especially in the area of leadership support. © 2013 John Wiley & Sons Ltd.

  16. Comparison in bone turnover markers during early healing of femoral neck fracture and trochanteric fracture in elderly patients

    Directory of Open Access Journals (Sweden)

    Shota Ikegami

    2009-10-01

    Full Text Available Healing of fractures is different for each bone and bone turnover markers may reflect the fracture healing process. The purpose of this study was to determine the characteristic changes in bone turnover markers during the fracture healing process. The subjects were consecutive patients with femoral neck or trochanteric fracture who underwent surgery and achieved bone union. There were a total of 39 patients, including 33 women and 6 men. There were 18 patients (16 women and 2 men with femoral neck fracture and 21 patients (17 women and 4 men with trochanteric fracture. Serum bone-specific alkaline phosphatase (BAP was measured as a bone formation marker. Urine and serum levels of N-terminal telopeptide of type I collagen (NTX, as well as urine levels of C-terminal telopeptide of type I collagen (CTX and deoxypyridinoline (DPD, were measured as markers of bone resorption. All bone turnover markers showed similar changes in patients with either type of fracture, but significantly higher levels of both bone formation and resorption markers were observed in trochanteric fracture patients than in neck fracture patients. BAP showed similar levels at one week after surgery and then increased. Bone resorption markers were increased after surgery in patients with either fracture. The markers reached their peak values at three weeks (BAP and urinary NTX, five weeks (serum NTX and DPD, and 2-3 weeks (CTX after surgery. The increase in bone turnover markers after hip fracture surgery and the subsequent decrease may reflect increased bone formation and remodeling during the healing process. Both fractures had a similar bone turnover marker profile, but the extent of the changes differed between femoral neck and trochanteric fractures.

  17. Comparison in bone turnover markers during early healing of femoral neck fracture and trochanteric fracture in elderly patients.

    Science.gov (United States)

    Ikegami, Shota; Kamimura, Mikio; Nakagawa, Hiroyuki; Takahara, Kenji; Hashidate, Hiroyuki; Uchiyama, Shigeharu; Kato, Hiroyuki

    2009-10-10

    Healing of fractures is different for each bone and bone turnover markers may reflect the fracture healing process. The purpose of this study was to determine the characteristic changes in bone turnover markers during the fracture healing process. The subjects were consecutive patients with femoral neck or trochanteric fracture who underwent surgery and achieved bone union. There were a total of 39 patients, including 33 women and 6 men. There were 18 patients (16 women and 2 men) with femoral neck fracture and 21 patients (17 women and 4 men) with trochanteric fracture. Serum bone-specific alkaline phosphatase (BAP) was measured as a bone formation marker. Urine and serum levels of N-terminal telopeptide of type I collagen (NTX), as well as urine levels of C-terminal telopeptide of type I collagen (CTX) and deoxypyridinoline (DPD), were measured as markers of bone resorption. All bone turnover markers showed similar changes in patients with either type of fracture, but significantly higher levels of both bone formation and resorption markers were observed in trochanteric fracture patients than in neck fracture patients. BAP showed similar levels at one week after surgery and then increased. Bone resorption markers were increased after surgery in patients with either fracture. The markers reached their peak values at three weeks (BAP and urinary NTX), five weeks (serum NTX and DPD), and 2-3 weeks (CTX) after surgery. The increase in bone turnover markers after hip fracture surgery and the subsequent decrease may reflect increased bone formation and remodeling during the healing process. Both fractures had a similar bone turnover marker profile, but the extent of the changes differed between femoral neck and trochanteric fractures.

  18. [A study of work values, professional commitment, turnover intention and related factors among clinical nurses].

    Science.gov (United States)

    Wang, Kuei-Ying; Chou, Chuan-Chiang; Huang, Jui-Lan

    2010-02-01

    The high rate of turnover in nursing positions is a global problem. There have been few studies done addressing the relationship between work values and nurse turnover intention. The purpose of this study was to explore the relationship between work values, professional commitment and turnover intention among clinical nurses. A cross-sectional survey was conducted between February 1st to March 10th, 2008 on a convenience sample of nurses, all of whom had at least a half year of work experience at one of four teaching hospitals in Taiwan. A total of 289 valid responses were received, with a response rate of 96.3%. Major findings included: (1) Nurses who were older, had more years of school, had worked more years, held specific job duties, earned a higher salary, held Buddhist beliefs, or were married with two or more children presented higher work values and professional commitment and lower turnover intention; (2) As a group, total work values and professional commitment scores corresponded negatively with turnover intention scores; (3) Significant factors affecting turnover intent in clinical nurses included professional commitment, institution characteristics, Buddhist beliefs and salary. These four variables accounted for 52.2% of the variation in turnover intention. This study indicated that nurses with higher work values and professional commitment tend to exhibit less turnover intention. It is highly recommended to develop strategies to bolster the teaching of altruistic values and professional commitment in nursing education in order to reduce turnover intent. Also, further studies on the influence of religious beliefs and organizational attributes on nurse turnover intentions are also suggested.

  19. Effects of breeder turnover and harvest on group composition and recruitment in a social carnivore.

    Science.gov (United States)

    Ausband, David E; Mitchell, Michael S; Waits, Lisette P

    2017-09-01

    Breeder turnover can influence population growth in social carnivores through changes to group size, composition and recruitment. Studies that possess detailed group composition data that can provide insights about the effects of breeder turnover on groups have generally been conducted on species that are not subject to recurrent annual human harvest. We wanted to know how breeder turnover affects group composition and how harvest, in turn, affects breeder turnover in cooperatively breeding grey wolves (Canis lupus Linnaeus 1758). We used noninvasive genetic sampling at wolf rendezvous sites to construct pedigrees and estimate recruitment in groups of wolves before and after harvest in Idaho, USA. Turnover of breeding females increased polygamy and potential recruits per group by providing breeding opportunities for subordinates although resultant group size was unaffected 1 year after the turnover. Breeder turnover had no effect on the number of nonbreeding helpers per group. After breeding male turnover, fewer female pups were recruited in the new males' litters. Harvest had no effect on the frequency of breeder turnover. We found that breeder turnover led to shifts in the reproductive hierarchies within groups and the resulting changes to group composition were quite variable and depended on the sex of the breeder lost. We hypothesize that nonbreeding females direct help away from non-kin female pups to preserve future breeding opportunities for themselves. Breeder turnover had marked effects on the breeding opportunities of subordinates and the number and sex ratios of subsequent litters of pups. Seemingly subtle changes to groups, such as the loss of one individual, can greatly affect group composition, genetic content, and short-term population growth when the individual lost is a breeder. © 2017 The Authors. Journal of Animal Ecology © 2017 British Ecological Society.

  20. Casein and soya-bean protein have different effects on whole body protein turnover at the same nitrogen balance

    DEFF Research Database (Denmark)

    Nielsen, K; Kondrup, J; Elsner, Petteri

    1994-01-01

    , or hydrolysed soya-bean protein at a level of 9.1 g/kg BW per d. The diets, which were isoenergetic with the same carbohydrate: fat ratio, were given as a continuous intragastric infusion for at least 4 d. During the last 19 h 15N-glycine (a primed continuous infusion) was given intragastrically and 15N...... synthesis. The protein diets produced a positive N balance which was independent of the protein source. Intact and hydrolysed casein increased protein synthesis 2.6- and 2.0-fold respectively, compared with the protein-free diet. Protein degradation increased 1.4- and 1.2-fold respectively. Hydrolysed soya-bean...... protein did not increase protein synthesis but decreased protein degradation by 35% compared with the protein-free diet. Compared with the hydrolysed soya-bean protein, intact casein resulted in 2.2- and 2.8-fold higher rates of protein synthesis and degradation respectively. These results are not easily...

  1. Leadership styles of nursing home administrators and their association with staff turnover.

    Science.gov (United States)

    Donoghue, Christopher; Castle, Nicholas G

    2009-04-01

    The purpose of this study was to examine the associations between nursing home administrator (NHA) leadership style and staff turnover. We analyzed primary data from a survey of 2,900 NHAs conducted in 2005. The Online Survey Certification and Reporting database and the Area Resource File were utilized to extract organizational and local economic characteristics of the facilities. A general linear model (GLM) was used to estimate the effects of NHA leadership style, organizational characteristics, and local economic characteristics on nursing home staff turnover for registered nurses (RNs), licensed practical nurses (LPNs), and nurse's aides (NAs). The complete model estimates indicate that NHAs who are consensus managers (leaders who solicit, and act upon, the most input from their staff) are associated with the lowest turnover levels, 7% for RNs, 3% for LPNs, and 44% for NAs. Shareholder managers (leaders who neither solicit input when making a decision nor provide their staffs with relevant information for making decisions on their own) are associated with the highest turnover levels, 32% for RNs, 56% for LPNs, and 168% for NAs. The findings indicate that NHA leadership style is associated with staff turnover, even when the effects of organizational and local economic conditions are held constant. Because leadership strategies are amenable to change, the findings of this study may be used to develop policies for lowering staff turnover.

  2. PENGARUH WORK OVERLOAD DAN WORK FAMILY CONFLICT TERHADAP TURNOVER INTENTION YANG DIMEDIASI OLEH WORK EXHAUSTION

    Directory of Open Access Journals (Sweden)

    Nurul Hidayatin Nisa

    2016-01-01

    Full Text Available The purpose of this research was to examine factors that determine turnover intention in medical representative at PT. APL. To be known before that medical representatives have high percentage in turnover. The research using work exhaustion as mediation to determine the relationship between works overload and work family conflict of turnover intention. Research method is quantitative approach in causal research. The analysis tools are AMOS and T-Sobel. Findings of this research are both work overload and work family conflict berpengaruh with work exhaustion and turnover intention, work exhaustion mediated work overload and work family conflict over turnover intention.

  3. Protein kinase C is activated in glomeruli from streptozotocin diabetic rats. Possible mediation by glucose

    International Nuclear Information System (INIS)

    Craven, P.A.; DeRubertis, F.R.

    1989-01-01

    Glomerular inositol content and the turnover of polyphosphoinositides was reduced by 58% in 1-2 wk streptozotocin diabetic rats. Addition of inositol to the incubation medium increased polyphosphoinositide turnover in glomeruli from diabetic rats to control values. Despite the reduction in inositol content and polyphosphoinositide turnover, protein kinase C was activated in glomeruli from diabetic rats, as assessed by an increase in the percentage of enzyme activity associated with the particulate cell fraction. Total protein kinase C activity was not different between glomeruli from control and diabetic rats. Treatment of diabetic rats with insulin to achieve near euglycemia prevented the increase in particulate protein kinase C. Moreover, incubation of glomeruli from control rats with glucose (100-1,000 mg/dl) resulted in a progressive increase in labeled diacylglycerol production and in the percentage of protein kinase C activity which was associated with the particulate fraction. These results support a role for hyperglycemia per se in the enhanced state of activation of protein kinase C seen in glomeruli from diabetic rats. Glucose did not appear to increase diacylglycerol by stimulating inositol phospholipid hydrolysis in glomeruli. Other pathways for diacylglycerol production, including de novo synthesis and phospholipase C mediated hydrolysis of phosphatidylcholine or phosphatidyl-inositol-glycan are not excluded

  4. Index Fund Selections with GAs and Classifications Based on Turnover

    Science.gov (United States)

    Orito, Yukiko; Motoyama, Takaaki; Yamazaki, Genji

    It is well known that index fund selections are important for the risk hedge of investment in a stock market. The`selection’means that for`stock index futures’, n companies of all ones in the market are selected. For index fund selections, Orito et al.(6) proposed a method consisting of the following two steps : Step 1 is to select N companies in the market with a heuristic rule based on the coefficient of determination between the return rate of each company in the market and the increasing rate of the stock price index. Step 2 is to construct a group of n companies by applying genetic algorithms to the set of N companies. We note that the rule of Step 1 is not unique. The accuracy of the results using their method depends on the length of time data (price data) in the experiments. The main purpose of this paper is to introduce a more`effective rule’for Step 1. The rule is based on turnover. The method consisting of Step 1 based on turnover and Step 2 is examined with numerical experiments for the 1st Section of Tokyo Stock Exchange. The results show that with our method, it is possible to construct the more effective index fund than the results of Orito et al.(6). The accuracy of the results using our method depends little on the length of time data (turnover data). The method especially works well when the increasing rate of the stock price index over a period can be viewed as a linear time series data.

  5. Centennial black carbon turnover observed in a Russia steppe soil

    Energy Technology Data Exchange (ETDEWEB)

    Hammes, K.; Torn, M.S.; Lapenas, A.G.; Schmidt, M.W.I.

    2008-09-15

    Black carbon (BC), from incomplete combustion of fuels and biomass, has been considered highly recalcitrant and a substantial sink for carbon dioxide. Recent studies have shown that BC can be degraded in soils. We use two soils with very low spatial variability sampled 100 years apart in a Russian steppe preserve to generate the first whole-profile estimate of BC stocks and turnover in the field. Quantities of fire residues in soil changed significantly over a century. Black carbon stock was 2.5 kg m{sup -2}, or about 7-10% of total organic C in 1900. With cessation of biomass burning, BC stocks decreased 25% over a century, which translates into a centennial soil BC turnover (293 years best estimate; range 182-541 years), much faster than so-called inert or passive carbon in ecosystem models. The turnover time presented here is for loss by all processes, namely decomposition, leaching, and erosion, although the latter two were probably insignificant in this case. Notably, at both time points, the peak BC stock was below 30 cm, a depth interval, which is not typically accounted for. Also, the quality of the fire residues changed with time, as indicated by the use benzene poly carboxylic acids (BPCA) as molecular markers. The proportions of less-condensed (and thus more easily degradable) BC structures decreased, whereas the highly condensed (and more recalcitrant) BC structures survived unchanged over the 100-year period. Our results show that BC cannot be assumed chemically recalcitrant in all soils, and other explanations for very old soil carbon are needed.

  6. Assessing the effect of dietary calcium intake and 25 OHD status on bone turnover in women in Pakistan.

    Science.gov (United States)

    Khan, Aysha Habib; Naureen, Ghazala; Iqbal, Romaina; Dar, Farhan Javed

    2013-01-01

    Bone health assessed in three towns of Karachi, Pakistan in females showed poor calcium intake, vitamin D deficiency, secondary hyperparathyroidism, and high bone turnover. Correlates of high bone turnover included females residing in Saddar Town, underweight females less than 30 years of age from low socio-economic status, and secondary hyperparathyroidism. To assess bone health and association of dietary calcium and 25 hydroxy vitamin D with bone turnover in the community-dwelling females of Karachi. Bone health was assessed in three randomly selected towns of Karachi, Pakistan. One premenopausal female fulfilling the inclusion criteria from each household was included in the study. Dietary calcium was assessed through a food frequency questionnaire and biochemical markers including calcium, phosphates, albumin, magnesium, creatinine, and SGPT, intact parathyroid hormone, 25 hydroxy vitamin D, and N-telopeptide of type I collagen were measured to assess the bone health. Three hundred and five females were included from three towns. Overall, 90.5% of females had vitamin D deficiency with 42.6 and 23.3% having secondary hyperparathyroidism and high bone turn over respectively. Prevalence of vitamin D deficiency, secondary hyperparathyroidism, and high bone turnover was significantly different among towns. Mean vitamin D levels were significantly low and iPTH levels significantly high in females with high bone turnover. Calcium intake was not significantly different among females with normal, high, and low bone turnover. Correlates of high bone turnover included females residing in Saddar Town, underweight females less than 30 years of age belonging to low socio-economic status, and secondary hyperparathyroidism. Compromised bone health is seen in community-dwelling females of Karachi. There is a need to perform large-scale community-based studies in all age groups to understand the interplay of markers in our population to understand the impact of these variables

  7. Maternal obesity modulates intracellular lipid turnover in the human term placenta.

    Science.gov (United States)

    Hirschmugl, B; Desoye, G; Catalano, P; Klymiuk, I; Scharnagl, H; Payr, S; Kitzinger, E; Schliefsteiner, C; Lang, U; Wadsack, C; Hauguel-de Mouzon, S

    2017-02-01

    Obesity before pregnancy is associated with impaired metabolic status of the mother and the offspring later in life. These adverse effects have been attributed to epigenetic changes in utero, but little is known about the role of placental metabolism and its contribution to fetal development. We examined the impact of maternal pre-pregnancy obesity on the expression of genes involved in placental lipid metabolism in lean and obese women. Seventy-three lean and obese women with healthy pregnancy were recruited at term elective cesarean delivery. Metabolic parameters were measured on maternal venous blood samples. Expression of 88 genes involved in lipid metabolism was measured in whole placenta tissue. Proteins of genes differently expressed in response to maternal obesity were quantified, correlated with maternal parameters and immunolocalized in placenta sections. Isolated primary trophoblasts were used for in vitro assays. Triglyceride (TG) content was increased in placental tissue of obese (1.10, CI 1.04-1.24 mg g -1 , Pwomen. Among target genes examined, six showed positive correlation (Pobese vs lean women. CGI-58 protein levels correlated positively with maternal insulin levels and pre-pregnancy body mass index (R=0.63, Ptreatment of cultured trophoblast cells. Pre-gravid obesity significantly modifies the expression of placental genes related to transport and storage of neutral lipids. We propose that the upregulation of CGI-58, a master regulator of TG hydrolysis, contributes to the turnover of intracellular lipids in placenta of obese women, and is tightly regulated by metabolic factors of the mother.

  8. A study on the magnitude and causes of turnover among academic ...

    African Journals Online (AJOL)

    Considering high turnover as a sign of failure in an educational organization, the study was conducted to assess the causes of turnover among the academic staffs of Ambo University. The study focused on six plausible factors: economic, managerial, environmental, social and technological, teaching related factors and ...

  9. Telaah Hubungan Kepuasan Kerja Dan Komitmen Organisasional Terhadap Turnover Intention

    OpenAIRE

    Ali Amran; Acep Rohendi

    2017-01-01

    ABSTRAK Karyawan merupakan elemen yang sangat penting bagi perusahaan. Karyawan sebagai sumber daya manusia adalah penggerak utama berjalannya roda perusahaan sehingga perusahaan harus menjaga kepuasan kerja dan komitmen organisasional agar karyawan tidak berkeinginan untuk berpindah ke perusahaan lain (turnover intention). Hal ini perlu dikaji pengaruh kepuasan kerja dan komitmen organisasional terhadap turnover intention sehingga dapat bermanfaat untuk mengetahui nilai penting dari kepu...

  10. Organizational Consequences of Staff Turnover in Outpatient Substance Abuse Treatment Programs

    Science.gov (United States)

    Knight, Danica K.; Edwards, Jennifer R.; Flynn, Patrick M.

    2014-01-01

    The purpose of this study was to examine the impact of staff turnover on perceptions of organizational demands and support among staff who remained employed in substance abuse treatment programs. The sample consisted of 353 clinical staff from 63 outpatient agencies. Two scales from the Survey of Organizational Functioning (SOF) measured work-environment demands (Stress, Inadequate Staffing), and three measured supportive work relationships (Communication, Cohesion, Peer Collaboration). Results from a series of multilevel models documented that counselors working in programs that had previously experienced high staff turnover perceived higher demands and lower support within their organization, even after controlling for other potentially burdensome factors such as budget, census, and individual measures of workload. Two individual-level variables, caseload and tenure, were important determinants of work-environment demands, but were not related to supportive work relationships. Findings suggest that staff turnover increases workplace demands and decreases perceptions of support, and underscore the need to reduce stress and minimize subsequent turnover among clinical staff. PMID:22154028

  11. The Modern Technologies to Reduce Turnover of Company Staff

    OpenAIRE

    Zaiko Tetiana O.; Poplavska Oksana M.

    2017-01-01

    The article is aimed at analyzing and substantiating the use in practice of modern technologies to reduce turnover of staff, which do not bear significant financial costs for the company. The authors have proved that non-material measures to reduce staff turnover in companies are becoming predominant nowadays. Among them as the most important are indicated: introduction of flexible schedule (mode) of work, transition to the remote form of employment, and distribution of internal shares, in pa...

  12. Both H4K20 mono-methylation and H3K56 acetylation mark transcription-dependent histone turnover in fission yeast

    International Nuclear Information System (INIS)

    Yang, Hanna; Kwon, Chang Seob; Choi, Yoonjung; Lee, Daeyoup

    2016-01-01

    Nucleosome dynamics facilitated by histone turnover is required for transcription as well as DNA replication and repair. Histone turnover is often associated with various histone modifications such as H3K56 acetylation (H3K56Ac), H3K36 methylation (H3K36me), and H4K20 methylation (H4K20me). In order to correlate histone modifications and transcription-dependent histone turnover, we performed genome wide analyses for euchromatic regions in G2/M-arrested fission yeast. The results show that transcription-dependent histone turnover at 5′ promoter and 3′ termination regions is directly correlated with the occurrence of H3K56Ac and H4K20 mono-methylation (H4K20me1) in actively transcribed genes. Furthermore, the increase of H3K56Ac and H4K20me1 and antisense RNA production was observed in the absence of the histone H3K36 methyltransferase Set2 and histone deacetylase complex (HDAC) that are involved in the suppression of histone turnover within the coding regions. These results together indicate that H4K20me1 as well as H3K56Ac are bona fide marks for transcription-dependent histone turnover in fission yeast.

  13. Both H4K20 mono-methylation and H3K56 acetylation mark transcription-dependent histone turnover in fission yeast

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Hanna [Department of Biological Sciences, Korea Advanced Institute of Science and Technology, 291 Daehak-ro, Yuseong-gu, Daejeon 34141 (Korea, Republic of); Kwon, Chang Seob [Department of Chemistry and Biology, Korea Science Academy of KAIST, Busan, 614-822 (Korea, Republic of); Choi, Yoonjung, E-mail: jjungii@kaist.ac.kr [Department of Biological Sciences, Korea Advanced Institute of Science and Technology, 291 Daehak-ro, Yuseong-gu, Daejeon 34141 (Korea, Republic of); Lee, Daeyoup, E-mail: daeyoup@kaist.ac.kr [Department of Biological Sciences, Korea Advanced Institute of Science and Technology, 291 Daehak-ro, Yuseong-gu, Daejeon 34141 (Korea, Republic of)

    2016-08-05

    Nucleosome dynamics facilitated by histone turnover is required for transcription as well as DNA replication and repair. Histone turnover is often associated with various histone modifications such as H3K56 acetylation (H3K56Ac), H3K36 methylation (H3K36me), and H4K20 methylation (H4K20me). In order to correlate histone modifications and transcription-dependent histone turnover, we performed genome wide analyses for euchromatic regions in G2/M-arrested fission yeast. The results show that transcription-dependent histone turnover at 5′ promoter and 3′ termination regions is directly correlated with the occurrence of H3K56Ac and H4K20 mono-methylation (H4K20me1) in actively transcribed genes. Furthermore, the increase of H3K56Ac and H4K20me1 and antisense RNA production was observed in the absence of the histone H3K36 methyltransferase Set2 and histone deacetylase complex (HDAC) that are involved in the suppression of histone turnover within the coding regions. These results together indicate that H4K20me1 as well as H3K56Ac are bona fide marks for transcription-dependent histone turnover in fission yeast.

  14. Turnover rates in microorganisms by laser ablation electrospray ionization mass spectrometry and pulse-chase analysis

    Energy Technology Data Exchange (ETDEWEB)

    Stopka, Sylwia A.; Mansour, Tarek R.; Shrestha, Bindesh [Department of Chemistry, W.M. Keck Institute for Proteomics Technology and Applications, The George Washington University, Washington, DC 20052 (United States); Maréchal, Éric; Falconet, Denis [Laboratoire de Physiologie Cellulaire et Végétale, UMR 5168, CEA-CNRS-INRA-Univ. Grenoble Alpes, Grenoble (France); Vertes, Akos, E-mail: vertes@gwu.edu [Department of Chemistry, W.M. Keck Institute for Proteomics Technology and Applications, The George Washington University, Washington, DC 20052 (United States)

    2016-01-01

    Biochemical processes rely on elaborate networks containing thousands of compounds participating in thousands of reaction. Rapid turnover of diverse metabolites and lipids in an organism is an essential part of homeostasis. It affects energy production and storage, two important processes utilized in bioengineering. Conventional approaches to simultaneously quantify a large number of turnover rates in biological systems are currently not feasible. Here we show that pulse-chase analysis followed by laser ablation electrospray ionization mass spectrometry (LAESI-MS) enable the simultaneous and rapid determination of metabolic turnover rates. The incorporation of ion mobility separation (IMS) allowed an additional dimension of analysis, i.e., the detection and identification of isotopologs based on their collision cross sections. We demonstrated these capabilities by determining metabolite, lipid, and peptide turnover in the photosynthetic green algae, Chlamydomonas reinhardtii, in the presence of {sup 15}N-labeled ammonium chloride as the main nitrogen source. Following the reversal of isotope patterns in the chase phase by LAESI-IMS-MS revealed the turnover rates and half-lives for biochemical species with a wide range of natural concentrations, e.g., chlorophyll metabolites, lipids, and peptides. For example, the half-lives of lyso-DGTS(16:0) and DGTS(18:3/16:0), t{sub 1/2} = 43.6 ± 4.5 h and 47.6 ± 2.2 h, respectively, provided insight into lipid synthesis and degradation in this organism. Within the same experiment, half-lives for chlorophyll a, t{sub 1/2} = 24.1 ± 2.2 h, and a 2.8 kDa peptide, t{sub 1/2} = 10.4 ± 3.6 h, were also determined. - Highlights: • High-throughput pulse-chase analysis using direct sampling of biological cells. • Ion mobility separation for the elucidation of isotopologs. • Identification of isotopologs in difference heat plots of DT vs. m/z. • Simultaneous determination of turnover rates for lipids and

  15. Formation and Maintenance of Robust Long-Term Information Storage in the Presence of Synaptic Turnover.

    Directory of Open Access Journals (Sweden)

    Michael Fauth

    2015-12-01

    Full Text Available A long-standing problem is how memories can be stored for very long times despite the volatility of the underlying neural substrate, most notably the high turnover of dendritic spines and synapses. To address this problem, here we are using a generic and simple probabilistic model for the creation and removal of synapses. We show that information can be stored for several months when utilizing the intrinsic dynamics of multi-synapse connections. In such systems, single synapses can still show high turnover, which enables fast learning of new information, but this will not perturb prior stored information (slow forgetting, which is represented by the compound state of the connections. The model matches the time course of recent experimental spine data during learning and memory in mice supporting the assumption of multi-synapse connections as the basis for long-term storage.

  16. Organisational Commitment, Job Satisfaction and Turnover ...

    African Journals Online (AJOL)

    This study investigated organisational commitment, job satisfaction and turnover intentions among records management personnel in Ondo State Civil Service, Akure, Nigeria. Simple random sampling technique was used to draw 240 subjects from a population size of 275 records management personnel.

  17. Reducing Operating Room Turnover Time for Robotic Surgery Using a Motor Racing Pit Stop Model.

    Science.gov (United States)

    Souders, Colby P; Catchpole, Ken R; Wood, Lauren N; Solnik, Jonathon M; Avenido, Raymund M; Strauss, Paul L; Eilber, Karyn S; Anger, Jennifer T

    2017-08-01

    Operating room (OR) turnover time, time taken between one patient leaving the OR and the next entering, is an important determinant of OR utilization, a key value metric for hospital administrators. Surgical robots have increased the complexity and number of tasks required during an OR turnover, resulting in highly variable OR turnover times. We sought to streamline the turnover process and decrease robotic OR turnover times and increase efficiency. Direct observation of 45 pre-intervention robotic OR turnovers was performed. Following a previously successful model for handoffs, we employed concepts from motor racing pit stops, including briefings, leadership, role definition, task allocation and task sequencing. Turnover task cards for staff were developed, and card assignments were distributed for each turnover. Forty-one cases were observed post-intervention. Average total OR turnover time was 99.2 min (95% CI 88.0-110.3) pre-intervention and 53.2 min (95% CI 48.0-58.5) at 3 months post-intervention. Average room ready time from when the patient exited the OR until the surgical technician was ready to receive the next patient was 42.2 min (95% CI 36.7-47.7) before the intervention, which reduced to 27.2 min at 3 months (95% CI 24.7-29.7) post-intervention (p system changes are needed to capitalize on that result. Pit stop and other high-risk industry models may inform approaches to the management of tasks and teams.

  18. Effects of long- and short-term management on the functional structure of meadows through species turnover and intraspecific trait variability.

    Science.gov (United States)

    Volf, Martin; Redmond, Conor; Albert, Ágnes J; Le Bagousse-Pinguet, Yoann; Biella, Paolo; Götzenberger, Lars; Hrázský, Záboj; Janeček, Štěpán; Klimešová, Jitka; Lepš, Jan; Šebelíková, Lenka; Vlasatá, Tereza; de Bello, Francesco

    2016-04-01

    The functional structures of communities respond to environmental changes by both species replacement (turnover) and within-species variation (intraspecific trait variability; ITV). Evidence is lacking on the relative importance of these two components, particularly in response to both short- and long-term environmental disturbance. We hypothesized that such short- and long-term perturbations would induce changes in community functional structure primarily via ITV and turnover, respectively. To test this we applied an experimental design across long-term mown and abandoned meadows, with each plot containing a further level of short-term management treatments: mowing, grazing and abandonment. Within each plot, species composition and trait values [height, shoot biomass, and specific leaf area (SLA)] were recorded on up to five individuals per species. Positive covariations between the contribution of species turnover and ITV occurred for height and shoot biomass in response to both short- and long-term management, indicating that species turnover and intraspecific adjustments selected for similar trait values. Positive covariations also occurred for SLA, but only in response to long-term management. The contributions of turnover and ITV changed depending on both the trait and management trajectory. As expected, communities responded to short-term disturbances mostly through changes in intraspecific trait variability, particularly for height and biomass. Interestingly, for SLA they responded to long-term disturbances by both species turnover and intraspecific adjustments. These findings highlight the importance of both ITV and species turnover in adjusting grassland functional trait response to environmental perturbation, and show that the response is trait specific and affected by disturbance regime history.

  19. The crowding-out effect of the extrinsic motivation: An empirical study on the turnover intention of members of the youth social organization

    Directory of Open Access Journals (Sweden)

    Zhang Yuting

    2016-01-01

    Full Text Available The youth voluntary organization has been outstanding in the social governance. Therefore it’s an important issue how to ensure its role played sustainably in the long term. Particularly in reality, a few youth voluntary organizations sometimes become lax and act no function due to the turnover of its members. So it can tell that it’s given a very realistic meaning to discuss the factors influencing the turnover intention of the management of the organization. Based on the theory of organizational identification, the essay tries to find out the members’ intrinsic motivation to join the youth voluntary organization and its impact on turnover intention, and to verify the regulating mechanism of extrinsic motivation to the organizational identification and the mediating mechanism of organizational identification to the turnover intention. The result of the study into members of the Zhejiang youth voluntary organization shows that: (1 the intrinsic intention has the most significant influence on the turnover of the members of the youth voluntary organization; (2 the organizational identification plays a mediating role between intrinsic motivation and turnover intention; (3 the relationship between intrinsic motivation and organizational identification will be moderated by extrinsic motivation. The result of this study releases a revelatory meaning to raise the organizational identification of the members and restrain their turnover intention.

  20. Tropical Estuarine Macrobenthic Communities Are Structured by Turnover Rather than Nestedness.

    Science.gov (United States)

    Medeiros, Carlinda Raílly; Hepp, Luiz Ubiratan; Patrício, Joana; Molozzi, Joseline

    2016-01-01

    Turnover (i.e., species substitution) and nestedness (i.e., subsets of species from more diverse locations), the two main mechanisms used to explain the beta diversity of biological communities, have different implications for biodiversity conservation. To better understand how these mechanisms contribute to beta diversity, we tested the following hypotheses: (i) greater dissimilarity in community composition occurs between estuarine zones than other hierarchical level studied; (ii) beta diversity in these communities develops by turnover in estuaries with a lower degree of anthropogenic impact, but by nestedness in estuaries with a greater degree of anthropogenic impact; and (iii) the structuring mechanism is independent of season. We studied two tropical estuaries (dry and wet seasons) that vary in terms of land-use of the drainage basins. Subtidal benthic macroinvertebrates were sampled along the estuarine gradient in each of the two estuaries. The additive partitioning approach to species diversity was used to determine the hierarchical scale with the greatest dissimilarity in community composition. General beta diversity was measured using the Sorensen dissimilarity index, partitioning the turnover and nestedness components. The greatest dissimilarity in the composition of the communities occurred between the zones along the estuarine gradient in both seasons (dry = 58.6%; wet = 46.3%). In the estuary with a lower degree of anthropogenic influence, benthic macroinvertebrate diversity was generated by turnover regardless of the season. In the estuary with a greater degree of anthropogenic impact, beta diversity was structured by turnover during the dry season and a combination of both mechanisms during the wet season. We conclude that turnover is the principal mechanism responsible for beta diversity in benthic macroinvertebrate communities in tropical estuaries.

  1. E3 Ubiquitin Ligase RNF125 Activates Interleukin-36 Receptor Signaling and Contributes to Its Turnover.

    Science.gov (United States)

    Saha, Siddhartha S; Caviness, Gary; Yi, Guanghui; Raymond, Ernest L; Mbow, M Lamine; Kao, C Cheng

    2018-01-01

    Signaling by the interleukin-36 receptor (IL-36R) is linked to inflammatory diseases such as psoriasis. However, the regulation of IL-36R signaling is poorly understood. Activation of IL-36R signaling in cultured cells results in an increased polyubiquitination of the receptor subunit, IL-1Rrp2. Treatment with deubiquitinases shows that the receptor subunit of IL-36R, IL-1Rrp2, is primarily polyubiquitinated at the K63 position, which is associated with endocytic trafficking and signal transduction. A minor amount of ubiquitination is at the K48 position that is associated with protein degradation. A focused siRNA screen identified RNF125, an E3 ubiquitin ligase, to ubiquitinate IL-1Rrp2 upon activation of IL-36R signaling while not affecting the activated IL-1 receptor. Knockdown of RNF125 decreases signal transduction by the IL-36R. Overexpression of RNF125 in HEK293T cells activates IL-36R signaling and increases the ubiquitination of IL-1Rrp2 and its subsequent turnover. RNF125 can coimmunoprecipitate with the IL-36R, and it traffics with IL-1Rrp2 from the cell surface to lysosomes. Mutations of Lys568 and Lys569 in the C-terminal tail of IL-1Rrp2 decrease ubiquitination by RNF125 and increase the steady-state levels of IL-1Rrp2. These results demonstrate that RNF125 has multiple regulatory roles in the signaling, trafficking, and turnover of the IL-36R. © 2017 S. Karger AG, Basel.

  2. Distribution of sterol carrier protein2 (SCP2) in rat tissues and evidence for slow turnover in liver and adrenal cortex

    International Nuclear Information System (INIS)

    Kharroubi, A.; Chanderbhan, R.; Fiskum, G.; Noland, B.J.; Scallen, T.J.; Vahouny, G.V.

    1986-01-01

    Sterol carrier protein 2 (SCP 2 ) has been implicated in the regulation of the terminal stages of hepatic cholesterol biosynthesis, and in sterol utilization for adrenal steroid hormone and hepatic bile acid synthesis. In the present studies, a highly sensitive radioimmunoassay, using [ 125 I] SCP 2 , has been developed. Highest levels of SCP 2 were found in rat liver with progressively lower levels in intestinal mucosa, adrenal, kidney, lung and testis. SCP 2 levels were low or absent in heart, brain, skeletal muscle and serum. Liver SCP 2 was largely (44%) associated with the microsomal fraction, while in adrenal, 46% was associated with mitochondria, a distribution which is consistent with the proposed roles for SCP 2 in these tissues. Levels of SCP 2 in AS 30D hepatoma cells were only 5% of those in normal liver. In liver there was no indication of diurnal rhythm of SCP 2 in the cytosol and only slight variation of the microsomal SCP 2 levels. Fasting has only slight effects on SCP 2 concentration of rat liver microsomes and cytosol. Neither ACTH nor cycloheximide treatment of rats had a significant effect on SCP 2 distribution in the adrenal. In general, these findings indicate that SCP 2 has a low turn-over rate

  3. Bone Turnover Status: Classification Model and Clinical Implications

    Science.gov (United States)

    Fisher, Alexander; Fisher, Leon; Srikusalanukul, Wichat; Smith, Paul N

    2018-01-01

    Aim: To develop a practical model for classification bone turnover status and evaluate its clinical usefulness. Methods: Our classification of bone turnover status is based on internationally recommended biomarkers of both bone formation (N-terminal propeptide of type1 procollagen, P1NP) and bone resorption (beta C-terminal cross-linked telopeptide of type I collagen, bCTX), using the cutoffs proposed as therapeutic targets. The relationships between turnover subtypes and clinical characteristic were assessed in1223 hospitalised orthogeriatric patients (846 women, 377 men; mean age 78.1±9.50 years): 451(36.9%) subjects with hip fracture (HF), 396(32.4%) with other non-vertebral (non-HF) fractures (HF) and 376 (30.7%) patients without fractures. Resalts: Six subtypes of bone turnover status were identified: 1 - normal turnover (P1NP>32 μg/L, bCTX≤0.250 μg/L and P1NP/bCTX>100.0[(median value]); 2- low bone formation (P1NP ≤32 μg/L), normal bone resorption (bCTX≤0.250 μg/L) and P1NP/bCTX>100.0 (subtype2A) or P1NP/bCTX0.250 μg/L) and P1NP/bCTXturnover (both markers elevated ) and P1NP/bCTX>100.0 (subtype 4A) or P1NP/bCTX75 years and hyperparathyroidism. Hypoalbuminaemia and not using osteoporotic therapy were two independent indicators common for subtypes 3, 4A and 4B; these three subtypes were associated with in-hospital mortality. Subtype 3 was associated with fractures (OR 1.7, for HF OR 2.4), age>75 years, chronic heart failure (CHF), anaemia, and history of malignancy, and predicted post-operative myocardial injury, high inflammatory response and length of hospital stay (LOS) above10 days. Subtype 4A was associated with chronic kidney disease (CKD), anaemia, history of malignancy and walking aids use and predicted LOS>20 days, but was not discriminative for fractures. Subtype 4B was associated with fractures (OR 2.1, for HF OR 2.5), age>75 years, CKD and indicated risks of myocardial injury, high inflammatory response and LOS>10 days. Conclusions: We

  4. The prospective effects of workplace violence on physicians' job satisfaction and turnover intentions: the buffering effect of job control.

    Science.gov (United States)

    Heponiemi, Tarja; Kouvonen, Anne; Virtanen, Marianna; Vänskä, Jukka; Elovainio, Marko

    2014-01-17

    Health care professionals, including physicians, are at high risk of encountering workplace violence. At the same time physician turnover is an increasing problem that threatens the functioning of the health care sector worldwide. The present study examined the prospective associations of work-related physical violence and bullying with physicians' turnover intentions and job satisfaction. In addition, we tested whether job control would modify these associations. The present study was a 4-year longitudinal survey study, with data gathered in 2006 and 2010.The present sample included 1515 (61% women) Finnish physicians aged 25-63 years at baseline. Analyses of covariance (ANCOVA) were conducted while adjusting for gender, age, baseline levels, specialisation status, and employment sector. The results of covariance analyses showed that physical violence led to increased physician turnover intentions and that both bullying and physical violence led to reduced physician job satisfaction even after adjustments. We also found that opportunities for job control were able to alleviate the increase in turnover intentions resulting from bullying. Our results suggest that workplace violence is an extensive problem in the health care sector and may lead to increased turnover and job dissatisfaction. Thus, health care organisations should approach this problem through different means, for example, by giving health care employees more opportunities to control their own work.

  5. Constituent attachment and voluntary turnover in low-wage/low-skill service work.

    Science.gov (United States)

    Ellingson, Jill E; Tews, Michael J; Dachner, Alison M

    2016-01-01

    This paper draws on life stage theory, ethnographic research conducted in the service sector, and evidence for secondary segmentation within the low-wage/low-skill labor force to offer evidence that social bond development with coworkers can help reduce the high rate of turnover observed in low-wage/low-skill service work. Contrary to the belief that these employees will leave before social ties can develop, constituent attachment was found to be the only significant predictor of turnover in 2 samples of front-line service workers in a casual dining, national restaurant chain after controlling for other aspects of work that can create a sense of attachment to a job, and other job attitudes, such as satisfaction and commitment. However, the effect was dependent on developmental life stage. Constituent attachment reduced turnover among workers classified as emerging adults, whereas constituent attachment did little to affect turnover among nonemerging adults. Implications of the results are discussed with respect to the value of considering segmentation in future research on turnover in the service sector and the use of life stage theory for understanding the leaving behavior of workers in different stages of adulthood. (c) 2016 APA, all rights reserved).

  6. Metabolic behavior of cell surface biotinylated proteins

    International Nuclear Information System (INIS)

    Hare, J.F.; Lee, E.

    1989-01-01

    The turnover of proteins on the surface of cultured mammalian cells was measured by a new approach. Reactive free amino or sulfhydryl groups on surface-accessible proteins were derivatized with biotinyl reagents and the proteins solubilized from culture dishes with detergent. Solubilized, biotinylated proteins were then adsorbed onto streptavidin-agarose, released with sodium dodecyl sulfate and mercaptoethanol, and separated on polyacrylamide gels. Biotin-epsilon-aminocaproic acid N-hydroxysuccinimide ester (BNHS) or N-biotinoyl-N'-(maleimidohexanoyl)hydrazine (BM) were the derivatizing agents. Only 10-12 bands were adsorbed onto streptavidin-agarose from undervatized cells or from derivatized cells treated with free avidin at 4 degrees C. Two-dimensional isoelectric focusing-sodium dodecyl sulfate gel electrophoresis resolved greater than 100 BNHS-derivatized proteins and greater than 40 BM-derivatized proteins. There appeared to be little overlap between the two groups of derivatized proteins. Short-term pulse-chase studies showed an accumulation of label into both groups of biotinylated proteins up until 1-2 h of chase and a rapid decrease over the next 1-5 h. Delayed appearance of labeled protein at the cell surface was attributed to transit time from site of synthesis. The unexpected and unexplained rapid disappearance of pulse-labeled proteins from the cell surface was invariant for all two-dimensionally resolved proteins and was sensitive to temperature reduction to 18 degrees C. Long-term pulse-chase experiments beginning 4-8 h after the initiation of chase showed the disappearance of derivatized proteins to be a simple first-order process having a half-life of 115 h in the case of BNHS-derivatized proteins and 30 h in the case of BM-derivatized proteins

  7. Cmr1/WDR76 defines a nuclear genotoxic stress body linking genome integrity and protein quality control

    DEFF Research Database (Denmark)

    Gallina, Irene; Colding, Camilla Skettrup; Henriksen, Peter

    2015-01-01

    DNA replication stress is a source of genomic instability. Here we identify changed mutation rate 1 (Cmr1) as a factor involved in the response to DNA replication stress in Saccharomyces cerevisiae and show that Cmr1-together with Mrc1/Claspin, Pph3, the chaperonin containing TCP1 (CCT) and 25...... other proteins-define a novel intranuclear quality control compartment (INQ) that sequesters misfolded, ubiquitylated and sumoylated proteins in response to genotoxic stress. The diversity of proteins that localize to INQ indicates that other biological processes such as cell cycle progression...... propose that Cmr1/WDR76 plays a role in the recovery from genotoxic stress through regulation of the turnover of sumoylated and phosphorylated proteins....

  8. Protein turnover and metabolism in the elderly intensive care unit patient

    NARCIS (Netherlands)

    Phillips, Stuart M.; Dickerson, Roland N.; Moore, Frederick A.; Paddon-Jones, Douglas; Weijs, Peter J. M.

    2017-01-01

    Many intensive care unit (ICU) patients do not achieve target protein intakes particularly in the early days following admittance. This period of iatrogenic protein undernutrition contributes to a rapid loss of lean, in particular muscle, mass in the ICU. The loss of muscle in older (aged >60 years)

  9. Protein carbonylation in plants

    DEFF Research Database (Denmark)

    Møller, Ian Max; Havelund, Jesper; Rogowska-Wrzesinska, Adelina

    2017-01-01

    This chapter provides an overview of the current knowledge on protein carbonylation in plants and its role in plant physiology. It starts with a brief outline of the turnover and production sites of reactive oxygen species (ROS) in plants and the causes of protein carbonylation. This is followed...... by a description of the methods used to study protein carbonylation in plants, which is also very brief as the methods are similar to those used in studies on animals. The chapter also focuses on protein carbonylation in plants in general and in mitochondria and in seeds in particular, as case stories where...... specific carbonylated proteins have been identified. Protein carbonylation appears to accumulate at all stages of seed development and germination investigated to date. In some cases, such as seed aging, it is probably simply an accumulation of oxidative damage. However, in other cases protein...

  10. The relationships between organisational citizenship behaviour, job satisfaction and turnover intention.

    Science.gov (United States)

    Tsai, Yafang; Wu, Shih-Wang

    2010-12-01

    This study aims to explore the relationships between organisational citizenship behaviour, job satisfaction and turnover intention. Because of the changing health policies landscape, Taiwan's hospital administrators are facing major cost reduction challenges. Specifically, the high turnover rate of nurses represents a hindrance and a human resource cost. This study focuses on ways of reducing the employee turnover rate through enhanced organisational citizenship behaviour and job satisfaction. A cross-sectional study. This study focuses on hospital nurses in Taiwan. Our research samples were obtained from one medical centre, three regional hospitals and seven district hospitals. Out of 300 questionnaires distributed among samples, 237 were completed and returned. Pearson's correlation was used to test for relationships among the main variables. One-way analysis of variance and Scheffé's post hoc analysis were employed to test the influence of demographic data on the main variables. The results reveal that the nurses' job satisfaction has a significantly positive correlation with organisational citizenship behaviour and a negative correlation with turnover intention. This study has proven that the turnover intention of clinical nurses is related to their organisational citizenship behaviour and job satisfaction. Hospital administrators can reduce the turnover intention by meeting nurses' needs and by promoting their organisational citizenship behaviour. Organisational citizenship behaviour involves behaviour that encourages staff to endeavour to voluntarily improve organisational performance without lobbying for compensation. Employees' job satisfaction includes satisfaction with the working environment or welfare programme in the context of human resource initiatives. Similarly, human resource protocols may serve as the starting point for promoting staff organisational citizenship behaviour. Administrators in clinical healthcare are encouraged to meet their

  11. Unsteady Flows Control Hydrologic Turnover Rates in Antarctic Hyporheic Zones

    Science.gov (United States)

    Wlostowski, A. N.; Gooseff, M. N.; McKnight, D. M.; Lyons, W. B.; Saelens, E.

    2016-12-01

    Hydrologic turnover of the hyporheic zone (HZ) is the process of HZ flowpaths receiving water and solutes from the stream channel while simultaneously contributing water and solutes from the HZ back to the stream channel. The influence of hydrologic turnover on HZ solute storage depends on the relative magnitude of hyporheic exchange rates (i.e. physical transport) and biogeochemical reaction rates. Because both exchange rates and reaction rates are unsteady in natural systems, the availability of solutes in the HZ is controlled by the legacy of hydraulic and biological conditions. In this study, we quantify the influence of unsteady flows on hydrologic turnover of the HZ. We study a glacial melt stream in the McMurdo Dry Valleys of Antarctica (MDVs). The MDVs provide an ideal setting for investigating hydrologic and chemical storage characteristics of HZs, because nearly all streamflow is generated from glacier melt and the HZ is vertically bounded by continuous permafrost. A dense network of shallow groundwater wells and piezometers was installed along a 60-meter reach of Von Guerard Stream. 12 days of continuous water level data in each well was used to compute the magnitude and direction of 2D hydraulic gradients between the stream channel and lateral hyporheic aquifer. Piezometers were sampled daily for stable isotope abundances. The direction and magnitude of the cross-valley (CV), perpendicular to the thalweg, component of hydraulic gradients is sensitive to daily flood events and exhibits significant spatial heterogeneity. CV gradients are consistently oriented from the hyporheic aquifer towards the stream channel on 2 sections of the study reach, whereas CV gradients are consistently oriented from the stream channel towards the hyporheic aquifer on 1 section. Three sections show diel changes in orientation of CV gradients, coincident with the passage of daily flood events. During a 4-day period of low flows, the HZ is isotopically distinct from the stream

  12. Organizational consequences of staff turnover in outpatient substance abuse treatment programs.

    Science.gov (United States)

    Knight, Danica K; Becan, Jennifer E; Flynn, Patrick M

    2012-03-01

    The purpose of this study was to examine the impact of staff turnover on perceptions of organizational demands and support among staff who remained employed in substance abuse treatment programs. The sample consisted of 353 clinical staff from 63 outpatient agencies. Two scales from the Survey of Organizational Functioning measured work environment demands (stress and inadequate staffing), and 3 measured supportive work relationships (communication, cohesion, and peer collaboration). Results from a series of multilevel models documented that counselors working in programs that had previously experienced high staff turnover perceived higher demands and lower support within their organization, even after controlling for other potentially burdensome factors such as budget, census, and individual measures of workload. Two individual-level variables, caseload and tenure, were important determinants of work environment demands but were not related to supportive work relationships. Findings suggest that staff turnover increases workplace demands, decreases perceptions of support, and underscores the need to reduce stress and minimize subsequent turnover among clinical staff. Copyright © 2012 Elsevier Inc. All rights reserved.

  13. The effect of positive interactions on temporal turnover of community composition along an environmental gradient.

    Directory of Open Access Journals (Sweden)

    Youshi Wang

    Full Text Available It has been demonstrated that the interplay between negative and positive interactions simultaneously shapes community structure and composition. However, few studies have attempted to examine the effect of facilitation on compositional changes in communities through time. Additionally, due to the difficulties in collecting the long-term data, it would be useful to indicate the rate of temporal turnover using a readily obtainable metric. Using an individual-based model incorporating plant strategies, we examined the role of facilitation on the temporal turnover of communities located at different positions along an environmental gradient for three model scenarios: CM without facilitation; CFM-U, a unimodal relationship between facilitation and environmental severity; and CFM-L, a positively linear relationship between facilitation and environmental severity. Our results demonstrated that facilitation could increase, decrease or have no remarkable effect on temporal turnover. The specific outcome depended on the location of the focal community across the environmental gradient and the model employed. Compared with CM, the inclusion of positive interactions (i.e. CFM-U and CFM-L, at intermediate environmental stress levels (such as S = 0.7 and 0.8 resulted in lower Bray-Curtis similarity values; at other severity levels, facilitation slowed down (such as S = 0.3 and 0.4 at low to medium stress levels, and S = 0.9 at high stress levels or had only a subtle effect (such as at S = 0.1 on temporal turnover. We also found that the coefficient of variation (CV in species abundances and the rate of temporal variability showed a significant quadratic relationship. Our theoretical analysis contributes to the understanding of factors driving temporal turnover in biotic communities, and presents a potential metric (i.e. CV in species abundances assessing the consequences of ongoing environmental change on community structure.

  14. The effect of positive interactions on temporal turnover of community composition along an environmental gradient.

    Science.gov (United States)

    Wang, Youshi; Yang, Zhiyong; Zhou, Shurong; Soininen, Janne; Ai, Dexiecuo; Li, Yali; Chu, Chengjin

    2013-01-01

    It has been demonstrated that the interplay between negative and positive interactions simultaneously shapes community structure and composition. However, few studies have attempted to examine the effect of facilitation on compositional changes in communities through time. Additionally, due to the difficulties in collecting the long-term data, it would be useful to indicate the rate of temporal turnover using a readily obtainable metric. Using an individual-based model incorporating plant strategies, we examined the role of facilitation on the temporal turnover of communities located at different positions along an environmental gradient for three model scenarios: CM without facilitation; CFM-U, a unimodal relationship between facilitation and environmental severity; and CFM-L, a positively linear relationship between facilitation and environmental severity. Our results demonstrated that facilitation could increase, decrease or have no remarkable effect on temporal turnover. The specific outcome depended on the location of the focal community across the environmental gradient and the model employed. Compared with CM, the inclusion of positive interactions (i.e. CFM-U and CFM-L), at intermediate environmental stress levels (such as S = 0.7 and 0.8) resulted in lower Bray-Curtis similarity values; at other severity levels, facilitation slowed down (such as S = 0.3 and 0.4 at low to medium stress levels, and S = 0.9 at high stress levels) or had only a subtle effect (such as at S = 0.1) on temporal turnover. We also found that the coefficient of variation (CV) in species abundances and the rate of temporal variability showed a significant quadratic relationship. Our theoretical analysis contributes to the understanding of factors driving temporal turnover in biotic communities, and presents a potential metric (i.e. CV in species abundances) assessing the consequences of ongoing environmental change on community structure.

  15. Effects of water and nitrogen addition on species turnover in temperate grasslands in northern China.

    Directory of Open Access Journals (Sweden)

    Zhuwen Xu

    Full Text Available Global nitrogen (N deposition and climate change have been identified as two of the most important causes of current plant diversity loss. However, temporal patterns of species turnover underlying diversity changes in response to changing precipitation regimes and atmospheric N deposition have received inadequate attention. We carried out a manipulation experiment in a steppe and an old-field in North China from 2005 to 2009, to test the hypothesis that water addition enhances plant species richness through increase in the rate of species gain and decrease in the rate of species loss, while N addition has opposite effects on species changes. Our results showed that water addition increased the rate of species gain in both the steppe and the old field but decreased the rates of species loss and turnover in the old field. In contrast, N addition increased the rates of species loss and turnover in the steppe but decreased the rate of species gain in the old field. The rate of species change was greater in the old field than in the steppe. Water interacted with N to affect species richness and species turnover, indicating that the impacts of N on semi-arid grasslands were largely mediated by water availability. The temporal stability of communities was negatively correlated with rates of species loss and turnover, suggesting that water addition might enhance, but N addition would reduce the compositional stability of grasslands. Experimental results support our initial hypothesis and demonstrate that water and N availabilities differed in the effects on rate of species change in the temperate grasslands, and these effects also depend on grassland types and/or land-use history. Species gain and loss together contribute to the dynamic change of species richness in semi-arid grasslands under future climate change.

  16. Turnover, staffing, skill mix, and resident outcomes in a national sample of US nursing homes.

    Science.gov (United States)

    Trinkoff, Alison M; Han, Kihye; Storr, Carla L; Lerner, Nancy; Johantgen, Meg; Gartrell, Kyungsook

    2013-12-01

    The authors examined the relationship of staff turnover to selected nursing home quality outcomes, in the context of staffing and skill mix. Staff turnover is a serious concern in nursing homes as it has been found to adversely affect care. When employee turnover is minimized, better care quality is more likely in nursing homes. Data from the National Nursing Home Survey, a nationally representative sample of US nursing homes, were linked to Nursing Home Compare quality outcomes and analyzed using logistic regression. Nursing homes with high certified nursing assistant turnover had significantly higher odds of pressure ulcers, pain, and urinary tract infections even after controlling for staffing, skill mix, bed size, and ownership. Nurse turnover was associated with twice the odds of pressure ulcers, although this was attenuated when staffing was controlled. This study suggests turnover may be more important in explaining nursing home (NH) outcomes than staffing and skill mix and should therefore be given greater emphasis.

  17. Centennial black carbon turnover observed in a Russian steppe soil

    Directory of Open Access Journals (Sweden)

    K. Hammes

    2008-09-01

    Full Text Available Black carbon (BC, from incomplete combustion of fuels and biomass, has been considered highly recalcitrant and a substantial sink for carbon dioxide. Recent studies have shown that BC can be degraded in soils. We use two soils with very low spatial variability sampled 100 years apart in a Russian steppe preserve to generate the first whole-profile estimate of BC stocks and turnover in the field. Quantities of fire residues in soil changed significantly over a century. Black carbon stock was 2.5 kg m−2, or about 7–10% of total organic C in 1900. With cessation of biomass burning, BC stocks decreased 25% over a century, which translates into a centennial soil BC turnover (293 years best estimate; range 182–541 years, much faster than so-called inert or passive carbon in ecosystem models. The turnover time presented here is for loss by all processes, namely decomposition, leaching, and erosion, although the latter two were probably insignificant in this case. Notably, at both time points, the peak BC stock was below 30 cm, a depth interval, which is not typically accounted for. Also, the quality of the fire residues changed with time, as indicated by the use benzene polycarboxylic acids (BPCA as molecular markers. The proportions of less-condensed (and thus more easily degradable BC structures decreased, whereas the highly condensed (and more recalcitrant BC structures survived unchanged over the 100-year period. Our results show that BC cannot be assumed chemically recalcitrant in all soils, and other explanations for very old soil carbon are needed.

  18. Transformational leadership moderates the relationship between emotional exhaustion and turnover intention among community mental health providers.

    Science.gov (United States)

    Green, Amy E; Miller, Elizabeth A; Aarons, Gregory A

    2013-08-01

    Public sector mental health care providers are at high risk for burnout and emotional exhaustion which negatively affect job performance and client satisfaction with services. Few studies have examined ways to reduce these associations, but transformational leadership may have a positive effect. We examine the relationships between transformational leadership, emotional exhaustion, and turnover intention in a sample of 388 community mental health providers. Emotional exhaustion was positively related to turnover intention, and transformational leadership was negatively related to both emotional exhaustion and turnover intention. Transformational leadership moderated the relationship between emotional exhaustion and turnover intention, indicating that having a transformational leader may buffer the effects of providers' emotional exhaustion on turnover intention. Investing in transformational leadership development for supervisors could reduce emotional exhaustion and turnover among public sector mental health providers.

  19. Patients with polymyositis show changes in muscle protein charges

    DEFF Research Database (Denmark)

    Bartels, E M; Jacobsen, Søren; Rasmussen, L

    1989-01-01

    Polymyositis (PM) appears with indolent proximal muscle weakness and is an inflammatory disease with breakdown of muscle cells. In our study the protein charge concentrations of the contractile proteins in the A and I bands were determined, applying a microelectrode technique. Patients with PM sh...

  20. Effects of growth state and 3H labeling level on RNA turnover in WI-38 fibroblasts and HeLa cells

    International Nuclear Information System (INIS)

    Sameshima, M.; Schlessinger, D.

    1981-01-01

    The rate of turnover of prelabeled RNA in WI-38 human diploid fibroblasts varied with the level of 3 H incorporated, the cell density of cultures, and the arrest of growth by senescence. The half-life of RNA in sparse cultures of growing WI-38 diploid fibroblasts depended on the level of [ 3 H]uridine incorporated; extrapolated to zero levels of incorporation, the half-life was 15 to 20 days. At any level of incorporated [ 3 H]uridine, however, RNA half-life decreased to 4 to 5 days in superconfluent cultures as the culture growth slowed. A similar shortening of half-life was observed when growth was stopped by 3 H irradiation or clonal senescence. However, the rate of turnover was not simply dependent on whether cells were growing; for example, turnover did not increase when growth was arrested by incubating cells in conditioned medium. HeLa and L cells also showed an RNA half-life of about 14 to 20 days with an increase in turnover rate of crowded cultures. However, this increase occurred at higher cell densities than with the diploid fibroblasts. Also, the growth rate and rate of RNA turnover of HeLa and L cells were much less affected by incorporated 3 H. The differential responses to confluence and 3 H label can explain the higher turnover rate of RNA in normal human fibroblasts compared to SV40-transformed cells [S.A. Liebhaber, S. Wolf, and D. Schlessinger, Cell 13, 121-127 (1978)