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101.
The use of corporate ombuds (“a neutral member of the corporation who provides confidential and informal assistance to employees in resolving work-related concerns and is outside the normal management control structure”) is a growing phenomenon among large U.S. corporations. In contrast to such classic approaches to dispute resolution as grievance procedures, arbitration, and lawsuits, ombuds use non-adversary methods. The paper closes with a detailed “idealized design” for an ombuds program usable for comparison with existing systems or as a starting point for the development of new ombuds positions. 相似文献
102.
Sandra Szlapinski Brenda Strutt Madeline Deane Edith Arany Jamie Bennett David J. Hill 《International journal of molecular sciences》2021,22(23)
Gestational diabetes mellitus results, in part, from a sub-optimal β-cell mass (BCM) during pregnancy. Artemisinins were reported to increase BCM in models of diabetes by α- to β-cell conversion leading to enhanced glucose tolerance. We used a mouse model of gestational glucose intolerance to compare the effects of an artemisinin (artesunate) on glycemia of pregnant mice with vehicle treatment (acetone) or no treatment. Animals were treated daily from gestational days (GD) 0.5 to 6.5. An intraperitoneal glucose tolerance test was performed prior to euthanasia at GD18.5 or post-partum. Glucose tolerance was significantly improved in both pregnant and non-pregnant mice with both artesunate and vehicle-alone treatment, suggesting the outcome was primarily due to the acetone vehicle. In non-pregnant, acetone-treated animals, improved glucose tolerance was associated with a higher BCM and a significant increase in bihormonal insulin and glucagon-containing pancreatic islet cells, suggesting α- to β-cell conversion. BCM did not differ with treatment during pregnancy or post-partum. However, placental weight was higher in acetone-treated animals and was associated with an upregulation of apelinergic genes. Acetone-treated animals had reduced weight gain during treatment despite comparable food consumption to non-treated mice, suggesting transient effects on nutrient uptake. The mean duodenal and ileum villus height was reduced following exposure to acetone. We conclude that acetone treatment may mimic transient fasting, resulting in a subsequent improvement in glucose tolerance during pregnancy. 相似文献
103.
One- and two-dimensional 1H and 13C NMR spectra were obtained for a variety of homopolysaccharides, including the glucans dextran and pullulan, and the fructans levan and inulin. The NMR results provided information about the primary structure of these polysaccharides. Our results are in agreement with those determined previously by methylation analysis and other classical methods. The number of α(1 → 44) and α(1 → 6) linkages could be quantitated for pullulan. The presence of a single nonreducing glucose residue in the polyfructose inulin could also be demonstrated. In the case of the branched polysaccharides dextran and levan, it was possible to determine the degree of branching. In addition for lower molecular weight polysaccharides such as inulin and partially hydrolyzed dextran, it was possible to detect signals arising from reducing and non-reducing end groups. Their approximate molecular weight could be determined by quantitation of these signals. 相似文献
104.
The use of one-dimensional Nuclear Magnetic Resonance (NMR) spectroscopy as applied to structural studies of starch, starch products and glycogen is reviewed. Proton, carbon-13 and phosphorus-31 NMR spectra of a range of starches and starch products are described. These spectra, particularly carbon-13 NMR spectra, permit one to obtain structural information regarding these molecules. From the proton NMR spectra, which can be obtained with greater sensitivity, it is possible to determine the DP (degree of polymerization, the average number of glucose units per molecule) and the degree of branching (the proportion of glucose units which are (1→6) linked) without recourse to chemical or enzymatic methods. Moreover, the anomer distribution of the reducing sugars can be determined by 1H or 13C NMR. Finally, some examples of the application of NMR to follow the time course of enzymatic digestion and sugar anomerization are discussed, as is the solid-state NMR of starch and glycogen. The phosphorus-31 NMR spectra provide information about the nature of the phosphate groups in potato starch. 相似文献
105.
LEAPs and Bounds—an Energy Demand and Constraint Optimised Model of the Irish Energy System 总被引:1,自引:0,他引:1
Fionn Rogan Caiman J. Cahill Hannah E. Daly Denis Dineen J. P. Deane Charlie Heaps Manuel Welsch Mark Howells Morgan Bazilian Brian P. Ó Gallachóir 《Energy Efficiency》2014,7(3):441-466
This paper builds a model of energy demand and supply for Ireland with a focus on evaluating, and providing insights for, energy efficiency policies. The demand-side comprises sectoral sub-models, with a detailed bottom–up approach used for the transport and residential sectors and a top–down approach used for the industry and services sectors. The supply side uses the linear programming optimisation features of the Open Source Energy Modelling System applied to electricity generation to calculate the least-cost solution. This paper presents the first national level model developed within the Long Range Energy Alternatives Planning software to combine detailed end-use analysis on the demand side with a cost-minimising optimisation approach for modelling the electricity generation sector. Through three scenarios over the period 2009–2020, the model examines the aggregate impact on energy demand of a selection of current and proposed energy efficiency policies. In 2020, energy demand in the energy efficiency scenario is 8.6 % lower than the reference scenario and 11.1 % lower in the energy efficiency?+?scenario. 相似文献
106.
This paper describes a method for quantifying wind farm availability using two different approaches and comparing the results. Wind turbine suppliers regularly guarantee turbine availability in terms of time. A typical value of 97% is generally taken as the industry standard. This paper shows that this guarantee can potentially under-compensate the wind farm operator for losses sustained depending on when the period of non-availability occurs. Here we present an alternative method to quantify wind farm availability based on energy, which relates the energy losses in an Irish wind farm in 2007 to periods of turbine non-availability. It is shown in this analysis completed at this operational wind farm that while the technical non-availability as a percentage of time is 3%, the percentage of energy lost during downtimes is actually 11%. Based on the financial analysis above, the financial losses are significant. To answer the question should wind turbine availability be time or energy based, this paper shows that it can be advantageous for wind turbine owners to have energy-based calculations as long as the developers have sufficient monitoring of not only wind speed but also SCADA data. 相似文献
107.
Plant secondary chemistry can vary among plant tissues, individuals, and populations, and this variation has population-level
consequences for upper trophic levels. In this study, we examined the multi-trophic consequences of variation in iridoid glycosides,
which are a component of plant defense against generalist herbivores and also contribute to the unpalatability of sequestering
herbivores to both vertebrate and invertebrate predators. Several populations of Catalpa bignonioides were located and examined for the presence of the Catalpa Sphinx, Ceratomia catalpae, a specialist herbivore of Catalpa. We quantified iridoid glycoside content in Catalpa Sphinx caterpillars and in damaged and undamaged C. bignonioides leaves. Overall, leaves of C. bignonioides that were damaged by Catalpa Sphinx caterpillars contained lower concentrations of two major iridoid glycosides, catalpol
and catalposide, than leaves of undamaged trees from naturally occurring populations. Catalpa Sphinx caterpillars sequester
only catalpol, and increasing catalpol and catalposide concentrations in leaves were associated with increased catalpol sequestration
by caterpillars. The parasitoid Cotesia congregata develops successfully inside catalpol-sequestering Catalpa Sphinx caterpillars, and we examined parasitoid larvae for the
presence of catalpol. Parasitoid larvae dissected from caterpillars contained catalpol, but at lower concentrations than their
host caterpillars. The variation in chemical defense documented here has rarely been documented over multiple trophic levels,
but such resolved systems are ideal for examining competing hypotheses about the effects of plant secondary metabolites on
higher trophic levels. 相似文献
108.
This study compared different methods of tissue preparation for extraction of iridoid glycosides sequestered by three species
of lepidopteran larvae. Junonia coenia is a specialist on plant species that produce iridoid glycosides, while the arctiids Estigmene acrea and Spilosoma congrua are both polyphagous and will eat plants that produce iridoid glycosides. Larvae of all three species were reared on leaves
of Plantago lanceolata, which produces two primary iridoid glycosides, aucubin and catalpol. Three methods of preparing the specimens before extraction
in methanol were compared in all three species: 1) larvae were flash-frozen in liquid nitrogen, 2) larvae were macerated fresh
in boiling methanol, or 3) larvae were macerated fresh in room temperature methanol. A set of J. coenia larvae was oven-dried before maceration as an additional treatment for this species only. Junonia coenia sequestered the most iridoid glycosides, while E. acrea sequestered the least, and S. congrua was intermediate. Estigmene acrea was poor at sequestering catalpol. Tissue preparation method only significantly influenced iridoid glycoside recovery from
S. congrua, with maceration in room-temperature methanol being the most effective of the three methods. This study shows that treatment
of insects prior to iridoid glycoside extraction can influence recovery of the compounds, and that the effects of treatment
may vary among different species. 相似文献
109.
Luteinizing hormone (LH) plays an important role in the reproductive cycles of all mammals. There is a large amount of both nucleotide and amino acid sequence data available for LH from eutherian mammals, but little is known about the primary structure of LH in marsupials. We have used consensus PCR primers to generate specific probes for screening pituitary cDNA libraries and report the cloning of the cDNAs encoding the alpha-subunit of LH (also shared by a number of other glycoprotein hormones) and the LH-specific beta-subunit, from the common brushtail possum, Trichosurus vulpecula, and the red kangaroo, Macropus rufus. Southern blotting experiments indicated that both genes are probably present as single copies. Comparison of the deduced marsupial protein sequences with homologous sequences from other vertebrates revealed a high degree of conservation, especially for the alpha-subunit. These sequences represent the first complete primary structures for a marsupial glycoprotein hormone to have been elucidated. 相似文献
110.
Guleryuz O.G. Lutwak E. Deane Yang Gaoyong Zhang 《IEEE transactions on information theory / Professional Technical Group on Information Theory》2002,48(8):2377-2383
We show that for a special class of probability distributions that we call contoured distributions, information-theoretic invariants and inequalities are equivalent to geometric invariants and inequalities of bodies in Euclidean space associated with the distributions. Using this, we obtain characterizations of contoured distributions with extremal Shannon and Renyi entropy. We also obtain a new reverse information-theoretic inequality for contoured distributions. 相似文献