bluuebunny/crossref_metadata_2025 huggingface dataset:
Contribution of a mutational bias in hepatitis C virus replication to the genetic barrier in the development of drug resistance
Authors: Powdrill Megan H. , Tchesnokov Egor P. , Kozak Robert A. , Russell Rodney S. , Martin Ross , Svarovskaia Evguenia S. , Mo Hongmei , Kouyos Roger D. , Götte Matthias
Published: December 2011

The development of resistance to direct-acting antivirals (DAAs) targeting the hepatitis C virus (HCV) can compromise therapy. However, mechanisms that determine prevalence and frequency of resistance-conferring mutations remain elusive. Here, we studied the fidelity of the HCV RNA-dependent RNA polymerase NS5B in an attempt to link the efficiency of mismatch formation with genotypic changes observed in vivo. Enzyme kinetic measurements revealed unexpectedly high error rates (approximately 10
-3
per site) for G∶U/U∶G mismatches. The strong preference for G∶U/U∶G mismatches over all other mistakes correlates with a mutational bias in favor of transitions over transversions. Deep sequencing of HCV RNA samples isolated from 20 treatment-naïve patients revealed an approximately 75-fold difference in frequencies of the two classes of mutations. A stochastic model based on these results suggests that the bias toward transitions can also affect the selection of resistance-conferring mutations. Collectively, the data provide strong evidence to suggest that the nature of the nucleotide change can contribute to the genetic barrier in the development of resistance to DAAs.
Neuronal and molecular substrates for optimal foraging in
Caenorhabditis elegans
Authors: Milward Kate , Busch Karl Emanuel , Murphy Robin Joseph , de Bono Mario , Olofsson Birgitta
Published: December 2011

Variation in food quality and abundance requires animals to decide whether to stay on a poor food patch or leave in search of better food. An important question in behavioral ecology asks when is it optimal for an animal to leave a food patch it is depleting. Although optimal foraging is central to evolutionary success, the neural and molecular mechanisms underlying it are poorly understood. Here we investigate the neuronal basis for adaptive food-leaving behavior in response to resource depletion in
Caenorhabditis elegans
, and identify several of the signaling pathways involved. The ASE neurons, previously implicated in salt chemoattraction, promote food-leaving behavior via a cGMP pathway as food becomes limited. High ambient O
2
promotes food-leaving via the O
2
-sensing neurons AQR, PQR, and URX. Ectopic activation of these neurons using channelrhodopsin is sufficient to induce high food-leaving behavior. In contrast, the neuropeptide receptor NPR-1, which regulates social behavior on food, acts in the ASE neurons, the nociceptive ASH neurons, and in the RMG interneuron to repress food-leaving. Finally, we show that neuroendocrine signaling by TGF-β/DAF-7 and neuronal insulin signaling are necessary for adaptive food-leaving behavior. We suggest that animals integrate information about their nutritional state with ambient oxygen and gustatory stimuli to formulate optimal foraging strategies.
Early integrin binding to Arg-Gly-Asp peptide activates actin polymerization and contractile movement that stimulates outward translocation
Authors: Yu Cheng-han , Law Jaslyn Bee Khuan , Suryana Mona , Low Hong Yee , Sheetz Michael P.
Published: December 2011

Integrin-mediated adhesions are critical for stem cell differentiation, cancer metastasis, and the immune response [Hynes RO (2009)
Science
326:1216–1219]. However, the mechanisms of early adhesion formation remain unclear, especially the effects of lateral clustering of integrins and the role of the Src family kinases. Using mobile Arg–Gly–Asp (RGD) peptide ligands on lipid bilayers with nano-fabricated physical barriers [Salaita K, et al. (2010)
Science
327:1380–1385], we observe surprising long-range lateral movements of ligated integrins during the process of cell spreading. Initially, RGD-activated integrin clusters stimulate actin polymerization that radiates from the clusters. Myosin II contraction of actin from adjacent clusters produces contractile pairs that move toward each other against barriers. Force generated by myosin II stimulates a Src kinase-dependent lamellipodial extension and outward movement of clusters. Subsequent retraction by myosin II causes inward movement of clusters. The final cell spread area increases with the density of periodic barriers. Early integrin clustering recruits adhesion proteins, talin, paxillin, and FAK, irrespective of force generation. However, recruitment of vinculin is only observed upon contraction. Thus, we suggest that integrin activation and early clustering are independent of lateral forces. Clustering activates Src-dependent actin polymerization from clusters. Myosin contraction of clusters to lines stimulates active spreading with outward forces from actin polymerization followed by a second wave of contraction. Many of these early mechanical steps are not evident in cells spreading on immobilized matrices perhaps because of the low forces involved. These observations can provide new targets to control integrin-dependent adhesion and motility.
Algorithmic design of self-folding polyhedra
Authors: Pandey Shivendra , Ewing Margaret , Kunas Andrew , Nguyen Nghi , Gracias David H. , Menon Govind
Published: December 2011

Self-assembly has emerged as a paradigm for highly parallel fabrication of complex three-dimensional structures. However, there are few principles that guide a priori design, yield, and defect tolerance of self-assembling structures. We examine with experiment and theory the geometric principles that underlie self-folding of submillimeter-scale higher polyhedra from two-dimensional nets. In particular, we computationally search for nets within a large set of possibilities and then test these nets experimentally. Our main findings are that (
i
) compactness is a simple and effective design principle for maximizing the yield of self-folding polyhedra; and (
ii
) shortest paths from 2D nets to 3D polyhedra in the configuration space are important for rationalizing experimentally observed folding pathways. Our work provides a model problem amenable to experimental and theoretical analysis of design principles and pathways in self-assembly.
Gating of the MlotiK1 potassium channel involves large rearrangements of the cyclic nucleotide-binding domains
Authors: Mari Stefania A. , Pessoa João , Altieri Stephen , Hensen Ulf , Thomas Lise , Morais-Cabral João H. , Müller Daniel J.
Published: December 2011

Cyclic nucleotide-regulated ion channels are present in bacteria, plants, vertebrates, and humans. In higher organisms, they are closely involved in signaling networks of vision and olfaction. Binding of cAMP or cGMP favors the activation of these ion channels. Despite a wealth of structural and studies, there is a lack of structural data describing the gating process in a full-length cyclic nucleotide-regulated channel. We used high-resolution atomic force microscopy (AFM) to directly observe the conformational change of the membrane embedded bacterial cyclic nucleotide-regulated channel MlotiK1. In the nucleotide-bound conformation, the cytoplasmic cyclic nucleotide-binding (CNB) domains of MlotiK1 are disposed in a fourfold symmetric arrangement forming a pore-like vestibule. Upon nucleotide-unbinding, the four CNB domains undergo a large rearrangement, stand up by ∼1.7 nm, and adopt a structurally variable grouped conformation that closes the cytoplasmic vestibule. This fully reversible conformational change provides insight into how CNB domains rearrange when regulating the potassium channel.
Sparse linear modeling of next-generation mRNA sequencing (RNA-Seq) data for isoform discovery and abundance estimation
Authors: Li Jingyi Jessica , Jiang Ci-Ren , Brown James B. , Huang Haiyan , Bickel Peter J.
Published: December 2011

Since the inception of next-generation mRNA sequencing (RNA-Seq) technology, various attempts have been made to utilize RNA-Seq data in assembling full-length mRNA isoforms de novo and estimating abundance of isoforms. However, for genes with more than a few exons, the problem tends to be challenging and often involves identifiability issues in statistical modeling. We have developed a statistical method called “sparse linear modeling of RNA-Seq data for isoform discovery and abundance estimation” (SLIDE) that takes exon boundaries and RNA-Seq data as input to discern the set of mRNA isoforms that are most likely to present in an RNA-Seq sample. SLIDE is based on a linear model with a design matrix that models the sampling probability of RNA-Seq reads from different mRNA isoforms. To tackle the model unidentifiability issue, SLIDE uses a modified Lasso procedure for parameter estimation. Compared with deterministic isoform assembly algorithms (e.g., Cufflinks), SLIDE considers the stochastic aspects of RNA-Seq reads in exons from different isoforms and thus has increased power in detecting more novel isoforms. Another advantage of SLIDE is its flexibility of incorporating other transcriptomic data such as RACE, CAGE, and EST into its model to further increase isoform discovery accuracy. SLIDE can also work downstream of other RNA-Seq assembly algorithms to integrate newly discovered genes and exons. Besides isoform discovery, SLIDE sequentially uses the same linear model to estimate the abundance of discovered isoforms. Simulation and real data studies show that SLIDE performs as well as or better than major competitors in both isoform discovery and abundance estimation. The SLIDE software package is available at
https://sites.google.com/site/jingyijli/SLIDE.zip
.
Insects.
Authors: Chown S. L.
Published: December 2011

In this chapter, several of the responses to climate change by insects (agricultural pests, pollinators, biological control agents, human and animal disease vectors) and the outcomes thereof are discussed. Further consideration is also given to these responses at two different levels: that of assemblage richness per se, and whether this might be useful for forecasting; and at the population level, dealing specifically with likely limits to responses and how these might further be comprehended. The largely neglected area of the potential impacts of bioengineering and biogeoengineering to mitigate climate change are also briefly examined.
Fish: freshwater ecosystems.
Authors: Linnansaari T. , Cunjak R. A.
Published: December 2011

This chapter focuses on cold adaptation in freshwater fish, and especially how predicted climate change may alter the winter environment and conditions in streams and lakes, and how selected freshwater fish are likely to respond. Consequently, geographical research is restricted to high latitude regions in northern North America, northern Eurasia, and the southernmost areas of South America (Argentina). It discusses climate change scenarios and models and model predictions for temperature and precipitation in selected regions. The effects of altered ice processes and winter flow on freshwater fish, changes in their winter growth and productivity, and intra- and interspecific interactions and population dynamics, are explored.
Strategies of molecular adaptation to climate change: the challenges for amphibians and reptiles.
Authors: Storey K. B. , Storey J. M.
Published: December 2011

This chapter discusses the lives of ectothermic terrestrial vertebrates (amphibians and reptiles) and how they are affected by and adapt to changing environmental conditions. The focus is on species that have adapted to life in seasonally cold environments and examine some of the specialized biochemical adaptations that support cold and freeze tolerance. The range of molecular mechanisms that are available to organisms to make adaptive changes to their biochemistry in response to environmental stress are highlighted. The climate change and ectothermic vertebrates; amphibian and reptile cold hardiness; principles of biochemical adaptation; enzymatic and metabolic adaptation; and regulation of gene expression are presented.
The relationship between climate warming and hibernation in mammals.
Authors: Frank C. L.
Published: December 2011

This chapter discusses the effects of climate warming on the mammalian phenologies. The predicted effects of climate warming on hibernation; and field studies on hibernation by eastern chipmunks (Tamias striatus) in southeastern New York, USA are highlighted.
Trees and boreal forests.
Authors: Olsen J. E. , Lee Y. K.
Published: December 2011

This chapter focuses on the effects of temperature on the growth-dormancy cycling of boreal forest trees. It includes recent warming-induced changes in phenology and growth in trees, adaptation techniques in response to global warming, and temperature effects in the growing season (photosynthesis and morphology). It also discusses dormancy and winter survival in a climate change perspective and temperature under embryogenesis affecting adaptive properties.
The paradoxical increase in freezing injury in a warming climate: frost as a driver of change in cold climate vegetation.
Authors: Ball M. C. , Harris-Pascal D. , Egerton J. J. G. , Lenné T.
Published: December 2011

Responses of cold climate vegetation to increasing temperature and CO2 are enormously complex and varied, but many general predictions can be made based on the interplay of temperature with the natural seasonal progression in phenological events and acclimation to temperature extremes. Paradoxically, greater freezing stress is predicted to occur in cold climate vegetation with increasing temperature, with the effects being amplified by increasing CO2. The vulnerability of frost, loss in snow cover and delay in the breaking of dormancy in a warming climate are all discussed.
Annual field crops.
Authors: Kosová K. , Prášil I. T.
Published: December 2011

In this chapter, a variety of cold adaptation mechanisms including reversible mechanisms of cold acclimatization as well as developmental adaptations (vernalization) are described. A special focus on the regulatory relationships between vernalization and acquisition of enhanced frost tolerance in the model species Arabidopsis thaliana and cereals (such as wheat and barley) from the tribe Triticeae is given.
The potential impact of climate change on temperate zone woody perennial crops.
Authors: Quamme H. A. , Neilsen D.
Published: December 2011

This chapter discusses the implication of climate change on production of horticultural-grown woody perennials that overwinter in the temperate zone. Freezing injury affects the survival of many temperate zone woody perennials and is a major constraint to the production of fruit and nut crop and many landscape plants. Although these plants have evolved a capacity to avoid or tolerate freezing, they suffer winter damage frequently and this affects survival or productivity. Low-temperature injury can occur in all parts of the plant depending upon tissue susceptibility, exposure, and stage of acclimatization. The level of cold hardiness during acclimatization varies with species and cultivar. This chapter reports how peach and apricot production in the Okanagan Valley (British Columbia, Canada) has been affected by climate change during the autumn and winter prior to harvest, for an 88-year period (1921-2008).
Plant invasion in India: an overview.
Authors: Kohli R. K. , Batish D. R. , Singh J. S. , Singh H. P. , Bhatt J. R.
Published: December 2011

This chapter describes the status and vulnerability of the Indian region to plant invasion, and presents the major invasive plants in India and their attributes (growth, reproduction, survival, stress response, allelopathic potential and dispersal, among other biological and ecological aspects related to invasion), as well as potential invasive plants in the process of establishment. The management of potential invasive species and established species is briefly discussed.
Invasive species: ecology and impact of Lantana camara invasions.
Authors: Sharma G. P. , Raghubanshi A. S.
Published: December 2011

This chapter describes the biological characteristics of invasive species (i.e. in terms of fitness homeostasis and phenotypic plasticity, interaction with animals, geographical range, vegetative reproduction, fire tolerance, competitive ability and allelopathy), the invasion process, and the deleterious effects of invasive species on ecosystem attributes, focusing on Lantana camara as one of the major invasive species in India. Management options against L. camara invasion are discussed.
Biology of Chromolaena odorata, Ageratina adenophora and Ageratina riparia: a review.
Authors: Tripathi R. S. , Yadav A. S. , Kushwaha S. P. S.
Published: December 2011

This chapter covers the reproductive potential, population ecology (competitive interaction, allelopathic interaction, and effects of soil moisture, light intensity, and soil nitrogen on population density), origin, geographical distribution, invasion and management (physical, biological and chemical control methods) of E. odoratum [Chromolaena odorata], E. riparium and E. adenophorum [E. trapezoideum].
Predicting the geographical distribution of an invasive species (Chromolaena odorata L. (King) & H.E. Robins) in the Indian subcontinent under climate change scenarios.
Authors: Barik S. K. , Adhikari D.
Published: December 2011

This chapter describes the application of ecological niche modelling (ENM) in depicting the current and future geographical distribution of C. odorata based on its ecological niche using 458 records collected for native range distributions in North and South America. The predictive capacity of the niche model transferred to the Indian subcontinent was evaluated by assessing the probability level at which the model was successful in correctly predicting the current distributional range of the selected species. The model calibration test for C. odorata in its native range yielded good results. Among the input environmental parameters, the climatic variables were more sensitive and contributed 62% to the structure of the modelled ecological niche of the species compared with the physiographic variables, which contributed only 38%. The thermal variables, i.e. mean annual temperature (20.4%) and mean annual minimum temperature (29%), governed the macro-scale niche characteristic. The niche model showed that the response of the species peaked at a mean annual temperature range of 15-25°C, and there was a consistent increase in responsiveness with an increase in mean annual minimum temperature. The niche model generated using native range distribution predicted most of the validation points in the northern part of the Indian subcontinent at >70% probability. However, some locations in central and southern India were predicted at a probability level of <30%. The areas suitable for C. odorata include Jammu and Kashmir, Himachal Pradesh, Uttarakhand and West Bengal in the central Himalayas, and Arunachal Pradesh, Sikkim, Meghalaya, Nagaland, Mizoram, Manipur and Assam in the eastern Himalayas. The model also shows environmental suitability in Gujarat, Maharashtra, Karnataka, Kerala, Tamil Nadu, Andhra Pradesh and Orissa. Areas adjacent to the Indian sub-region showing high suitability for the species include Nepal, Myanmar and Pakistan. The Western and Eastern Ghats, the central Himalayan region, and the northeastern part of the Indian subcontinent are shown to be more susceptible to invasion by C. odorata under current climatic conditions and predicted future climate warming.
A brief appraisal of genus Potamogeton L. in the Kashmir valley.
Authors: Ganie A. H. , Reshi Z. A. , Wafai B. A.
Published: December 2011

This chapter briefly covers the geographical distribution (Asia, South America, North America, Europe, Australia and Africa), growth form and habitat preference, modes of reproduction, and invasion status of Potamogeton spp. in Kashmir Valley, India.
Remote sensing of invasive alien plant species.
Authors: Kushwaha S. P. S.
Published: December 2011

This chapter describes the applications of remote sensing in the study of the spatial distribution of invasive alien species and the monitoring of infestation of an area by these species. The results of studies on Eichhornia crassipes and Lantana camara in India are summarized.
Invasive alien plants in tropical forests of the South-eastern Ghats, India: ecology and management.
Authors: Parthasarathy N. , Pragasan L. A. , Muthumperumal C.
Published: December 2011

This chapter presents a study on the diversity and ecology of invasive alien plants in the forests of the southern Eastern Ghats, and some measures to control the spread of invasive species. The study was conducted in the tropical forests of six major hill complexes in Tamil Nadu, India, i.e. Bodamalais (BM), Chitteris (CH), Kalrayan (KA), Kolli hills (KO), Pachamalais (PM) and Shervarayans (SH). Of the 47 alien species, herb diversity was greatest (26 species), followed by trees (12 species), lianas (6 species) and shrubs (3 species). Total and alien species diversity and abundance of woody species (trees and lianas) varied across the sites. A positive correlation was observed between total tree and liana diversity, between total tree and liana abundance, and between alien tree and alien liana diversity, but not between alien tree and liana abundance. The most abundant alien species included Acacia farnesiana and Tamarindus indica among the trees, and Lantana camara and Rubus niveus among the lianas. In general, the diaspores of the alien invasive plants are dispersed by the autochorous mode (53%), followed by zoochory (38%) and anemochory (9%). The trees and lianas with fleshy fruits (berry or drupe) are largely dispersed by the zoochorous mode, followed by the shrubs. The autochorous mode of dispersal was prevalent in herbs. Among the sites, BM recorded the highest disturbance score, followed by PM, CH, KA, KO and SH. The diversity of total and alien tree species was negatively correlated with site disturbance scores.
Plant invasions in Jammu and Kashmir state, India.
Authors: Khuroo A. A. , Reshi Z. A. , Dar G. H. , Hamal I. A.
Published: December 2011

This chapter summarizes research on plant invasions in Jammu and Kashmir, India. A conceptual framework that has been followed to study plant invasions within the state is outlined, and a critical review of the progress in plant invasion research in three distinct regions (Kashmir, Jammu and Ladakh) is presented. Current knowledge gaps and future challenges to a better scientific understanding and management of plant invasions in the state are discussed.
Economics of invasive alien species.
Authors: Vinish Kathuria Vinish Kathuria , Singh S. P.
Published: December 2011

This chapter discusses why the management or spread of invasive alien species (IAS) is an economic issue, and summarizes the economic impact of invasive species at the international scale. The economic impact of IAS in India and efforts to control the spread of IAS in the region are covered. Issues with regard to the control of IAS are discussed. Tabulated data on sources of invasive species and their economic impact in agricultural, coastal, forest, freshwater and grassland ecosystems, and on the economic impact of Prosopis juliflora are presented.
Control of Lantana and restoration of biodiversity in reserve forests of Chandigarh: a case study.
Authors: Ishwar Singh Ishwar Singh
Published: December 2011

This chapter briefly discusses the ecological and environmental impacts of L. camara, and describes management strategies (removal of the causes of weed infestation and physical removal of L. camara) for the eradication of this invasive weed in forest reserves in Chandigarh, India, including the Sukhna Wildlife Sanctuary.
THE EUROPEAN WORLD OF TEMPORARY EMPLOYMENT
Authors: Van Lancker Wim
Published: December 2011

Departing from growing concerns about in-work poverty and the proliferation of flexible employment, we investigate the association between temporary employment and poverty in a European comparative perspective. In doing so, we focus specifically on possible gender dimensions, because some are concerned that the impact of flexible employment on income security will be different for men and women and that gender inequality will increase. By means of a logistic multilevel model, we analyse recent EU-SILC data for 24 European countries. The results show that the temporarily employed have a higher poverty risk vis-à-vis permanent workers, mainly caused by lower wages. However, the risk factors to become working poor are similar. The poorly educated, young workers and those living in a single earner household with dependent children have an increased probability to live in poverty, whether they are employed on temporary or permanent basis. Differences between European welfare regimes demonstrate that policy constellations influence the magnitude of these risk factors. Counter-intuitively, temporary working women have a lower poverty risk than their male counterparts. They are better protected because they are more often secondary earners in a dual earning household, while men are more often primary earners. This article advances knowledge on the linkages between temporary employment, economic insecurity and gender differences in European welfare states.
Safety Assessment and Pharmacokinetics of Intrathecal Methylprednisolone Acetate in Dogs
Authors: Rijsdijk Mienke , van Wijck Albert J. M. , Kalkman Cor J. , Meulenhoff P. C. Willem , Grafe Marjorie R. , Steinauer Joanne , Yaksh Tony L.
Published: December 2011

Background

Intrathecal methylprednisolone acetate (MPA) has been used in patients with chronic pain syndromes. Its safety has been debated after reports of adverse events. No systematic preclinical evaluation of MPA has been reported. In the current study, the acute and long-term effects of intrathecal MPA on dog spinal tissue was studied with the injectate reformulated to include minimal adjuvants.

Methods

Seventeen dogs were implanted with intrathecal catheters and randomized to three groups: vehicle (lidocaine; 4 dogs), MPA 20 mg/ml (human dose; 7 dogs), and MPA 80 mg/ml (maximum deliverable dose; 6 dogs). In parallel with the human protocols, dogs received four injections at 7-day intervals. Clinical observations and plasma methylprednisolone measurements were done before and at intervals after intrathecal delivery. One week (acute) or 6 weeks (long-term) after the last injection, animals were sacrificed and spinal tissues harvested for histopathology.

Results

Other than a brief motor block, no adverse clinical event occurred in any animal. Group A (vehicle) showed minimal histologic changes (median histology-score; acute: 1.3, long-term: 1.0). Group B (MPA 20 mg/ml) had a diffuse inflammatory reaction (acute: 2.0, long-term: 3.0), group C (MPA 80 mg/ml) a severe inflammatory response, with large inflammatory masses (acute: 4.0, long-term: 7.0) The severity of the inflammatory reaction increased significantly with increasing dose at long-term sacrifice (acute P = 0.167, long-term P = 0.014). No neuronal injury, demyelination, or gliosis was seen in any animal.

Conclusion

These results, showing dose-dependent intrathecal inflammatory reactions at MPA doses and injectate concentrations comparable to those used in humans, indicate that the continued use of this modality in humans is not recommended.
Predictors of Pain Relieving Response to Sympathetic Blockade in Complex Regional Pain Syndrome Type 1
Authors: van Eijs Frank , Geurts José , van Kleef Maarten , Faber Catharina G. , Perez Roberto S. , Kessels Alfons G.H. , Van Zundert Jan
Published: December 2011

Background

Sympathetic blockade with local anesthetics is used frequently in the management of complex regional pain syndrome type 1(CRPS-1), with variable degrees of success in pain relief. The current study investigated which signs or symptoms of CRPS-1 could be predictive of outcome. The incidence of side effects and complications of sympathetic blockade also were determined prospectively.

Methods

A prospective observational study was done of 49 patients with CRPS-1 in one extremity only and for less than 1-yr duration who had severe pain and persistent functional impairment with no response to standard treatment with medication and physical therapy.

Results

Fifteen (31%) patients had good or moderate response. The response rate was not different in patient groups with cold or warm type CRPS-1 or in those with more or less than 1.5°C differential increase in skin temperature after sympathetic blockade. Allodynia and hypoesthesia were negative predictors for treatment success in CRPS-1. There were no symptoms or signs of CRPS-1 that positively predicted treatment success. A majority of patients (84%) experienced transient side effects such as headache, dysphagia, increased pain, backache, nausea, blurred vision, groin pain, hoarseness, and hematoma at the puncture site. No major complications were reported.

Conclusions

The presence of allodynia and hypoesthesia are negative predictors for treatment success. The selection of sympathetic blockade as treatment for CRPS-1 should be balanced carefully between potential success and side effect ratio. The procedure is as likely to cause a transient increase in pain as a decrease in pain. Patients should be informed accordingly.
The nuclear receptor PPARβ/δ programs muscle glucose metabolism in cooperation with AMPK and MEF2
Authors: Gan Zhenji , Burkart-Hartman Eileen M. , Han Dong-Ho , Finck Brian , Leone Teresa C. , Smith Emily Y. , Ayala Julio E. , Holloszy John , Kelly Daniel P.
Published: December 2011

To identify new gene regulatory pathways controlling skeletal muscle energy metabolism, comparative studies were conducted on muscle-specific transgenic mouse lines expressing the nuclear receptors peroxisome proliferator-activated receptor α (PPARα; muscle creatine kinase [MCK]-PPARα) or PPARβ/δ (MCK-PPARβ/δ). MCK-PPARβ/δ mice are known to have enhanced exercise performance, whereas MCK-PPARα mice perform at low levels. Transcriptional profiling revealed that the lactate dehydrogenase b (Ldhb)/Ldha gene expression ratio is increased in MCK-PPARβ/δ muscle, an isoenzyme shift that diverts pyruvate into the mitochondrion for the final steps of glucose oxidation. PPARβ/δ gain- and loss-of-function studies in skeletal myotubes demonstrated that PPARβ/δ, but not PPARα, interacts with the exercise-inducible kinase AMP-activated protein kinase (AMPK) to synergistically activate Ldhb gene transcription by cooperating with myocyte enhancer factor 2A (MEF2A) in a PPARβ/δ ligand-independent manner. MCK-PPARβ/δ muscle was shown to have high glycogen stores, increased levels of GLUT4, and augmented capacity for mitochondrial pyruvate oxidation, suggesting a broad reprogramming of glucose utilization pathways. Lastly, exercise studies demonstrated that MCK-PPARβ/δ mice persistently oxidized glucose compared with nontransgenic controls, while exhibiting supranormal performance. These results identify a transcriptional regulatory mechanism that increases capacity for muscle glucose utilization in a pattern that resembles the effects of exercise training.
Control of Starch Granule Numbers in Arabidopsis Chloroplasts
Authors: Crumpton-Taylor Matilda , Grandison Scott , Png Kenneth M.Y. , Bushby Andrew J. , Smith Alison M.
Published: December 2011

The aim of this work was to investigate starch granule numbers in Arabidopsis (Arabidopsis thaliana) leaves. Lack of quantitative information on the extent of genetic, temporal, developmental, and environmental variation in granule numbers is an important limitation in understanding control of starch degradation and the mechanism of granule initiation. Two methods were developed for reliable estimation of numbers of granules per chloroplast. First, direct measurements were made on large series of consecutive sections of mesophyll tissue obtained by focused ion beam-scanning electron microscopy. Second, average numbers were calculated from the starch contents of leaves and chloroplasts and estimates of granule mass based on granule dimensions. Examination of wild-type plants and accumulation and regulation of chloroplast (arc) mutants with few, large chloroplasts provided the following new insights. There is wide variation in chloroplast volumes in cells of wild-type leaves. Granule numbers per chloroplast are correlated with chloroplast volume, i.e. large chloroplasts have more granules than small chloroplasts. Mature leaves of wild-type plants and arc mutants have approximately the same number of granules per unit volume of stroma, regardless of the size and number of chloroplasts per cell. Granule numbers per unit volume of stroma are also relatively constant in immature leaves but are greater than in mature leaves. Granule initiation occurs as chloroplasts divide in immature leaves, but relatively little initiation occurs in mature leaves. Changes in leaf starch content over the diurnal cycle are largely brought about by changes in the volume of a fixed number of granules.
Personalization in library databases: not persuasive enough?
Authors: McLaughlin Jean E.
Published: December 2011

Purpose

The intersection of persuasive technology and personalization features in enterprises such as Amazon.com delivers familiar consumer web interactions related to the purchase of goods. This paper aims to describe the intersection in terms of academic library database personalization features, persuasive technology, and student research.

Design/methodology/approach

The paper compares personalization features in popular academic library databases and a case study of usage in a university system provides a perspective on use in the academic community. Research on student use of technology related to databases and Web 2.0 provides information on potential and actual use of personalization features.

Findings

Personalization and filtering features of research databases and the evolving Web 2.0 technology platform offer helpful tools to researchers, but the technology may not be persuasive enough to make significant changes in research behavior. Usage statistics indicate that personalization features are used, but compared to total enrollment, use is not high. There is much room for extension of persuasive elements in library databases.

Research limitations/implications

There are many areas for exploration in determining how personalization may best be used in the future. This includes observing trends in usage, understanding users and their needs, and future technology changes.

Practical implications

Librarians can provide instruction about personalization in library databases in multiple forms. Suggestions for extensions of technology provide a view of possible personalization enhancements including persuasive elements.

Originality/value

The description of the intersection of personalization and persuasive technology in the academic library database environment is unique. The paper's comparison of personalization features of academic library databases provides a view of features and options within popular library databases.
Millennials and the adoption of new technologies in libraries through the diffusion of innovations process
Authors: Blackburn Heidi
Published: December 2011

Purpose

Literature on the features of new technology in libraries of every type and size is readily available, but looking at the factors playing a part in the process (relative advantage, compatibility, complexity, trialability and observability) will bring an understanding of how Millennials integrate technology into libraries. This paper seeks to discuss some of the issues involved.

Design/methodology/approach

This research focuses on Millennials and their adoption of new technologies in libraries through the process of diffusion and the stages of adoption as outlined by Everett Rogers: communication through certain channels; over time; and among members of a social system. Among these sections, Millennials as innovators and early adopters are explored, as well as the five stages of the innovation decision process.

Findings

Libraries have increasingly seen technology become a quick candidate as a solution to nearly every problem existing in the field. Though rapidly suggested as an alternative, the new technology is not adopted as quickly as in other sectors. However, Millennials act as change agents and bring technology‐driven attitudes to work, using specific communication channels to change employee attitudes towards adoption of the new tools.

Originality/value

Although applied to different fields, few studies have been conducted using the theory of diffusion in library science with a focus on innovation; rather the focus has been on technology adoption. The paper highlights how looking at the overarching trend, instead of focusing on the specifics of one single technology tool, will help researchers, administrators and practitioners understand the paradigm shift in the rapid adoption of such tools overall.
Role of policies in collaborative design process for digital libraries within African higher education
Authors: Ngimwa Pauline , Adams Anne
Published: December 2011

Purpose

This paper aims to explore the role of institutional and national policies in the design process of educational digital libraries developed collaboratively with key stakeholders within the African higher education context.

Design/methodology/approach

A qualitative research project based on three case studies of universities in Africa (Uganda, Kenya, Uganda) was carried out; comprising a retrospective review of the design process of ten innovative digital libraries through 38 in‐depth interviews with key design stakeholders. The interviews were conducted between September and December, 2009, while the data were triangulated with observations and documentary evidence from key policies.

Findings

Institutional and national policies were found to have tremendous impact on the design process of digital libraries as well as on their sustainability. Their absence in the design process was found to stifle innovation.

Research limitations/implications

This research was limited to the design process of digital libraries in African higher education. The research findings suggest that policy makers are important design gatekeepers and as such digital library designers should actively review relevant national and institutional policies, incorporate the implications of policies into design processes, and help to develop relevant policies.

Originality/value

The paper provides an understanding of the critical impact policies have with respect to supporting the design of educational digital libraries that are developed collaboratively with stakeholders. The retrospective review of completed digital library design processes carried out offers a different methodological approach for obtaining a high level understanding of the phenomenon under investigation.
Evaluation of the resource utilization efficiency of university libraries using DEA techniques and a proposal of alternative evaluation variables
Authors: Noh Younghee
Published: December 2011

Purpose

This paper seeks to rediscover the most suitable efficiency evaluation variables (input and output variables) for digital libraries and to employ the data envelopment analysis (DEA) model to measure the resource utilization efficiency of university libraries.

Design/methodology/approach

In order to analyze and evaluate university library efficiency, the paper introduces the DEA‐CCR Model and the DEA‐BCC Model. Based on these research tools, the Technical Efficiency (CCR*BCC) was determined. First, a reference group was created with a 100 percent efficiency rate, then the factors contributing to inefficient DMUs were analyzed, and the difference in the efficiency rate compared according to the different governing bodies of the libraries. Finally, the difference of efficiency according to the introduction and rejection of electronic resources was analyzed. It was possible to measure the technical efficiency, pure‐technical efficiency, and scale efficiency.

Findings

The results showed that the efficiency of university libraries varied significantly according to whether or not electronic resources were included in the evaluation. In addition, the findings confirmed decision making units (DMUs) have a 100 percent efficiency rate and a low efficiency rate as well as proposed benchmarking DMUs for inefficient DMUs and a direction for future improvements.

Originality/value

The paper identifies that there was a significant difference in efficiency, according to the presence of electronic resources in university libraries.
Personal information management (PIM), reference management and mind maps: the way to creative librarians?
Authors: Fourie Ina
Published: December 2011

Purpose

This column aims to explore the potential of personal information management (PIM) and reference management. It focuses on combining the use of PIM and reference management software with mind maps to stimulate the creative and innovative use of information collected

Design/methodology/approach

Following a brief review of the literature on the topic per se, awareness is raised of appropriate software and the potential of mind maps. The column is written against the background of research from information behaviour, PIM, mind maps, creativity, innovation and the reflective and evidence‐focused librarian.

Findings

There is growing emphasis on more than information literacy skills and the responsible use of information. Creative and innovative use of information is stressed. More intensive use and exploitation of information is necessary to justify the time and effort spent in using PIM and reference management software. Mind maps and collaboration might support creative and innovative use of information, and need to be further exploited. Although software is strong in supporting collaboration, there is very limited built‐in support for the combination of features for information and reference management with features for mind maps.

Originality/value

Although much has been published on developments in PIM and reference management, there is limited coverage of combining PIM and reference management with the use of mind maps and creativity, reflection and noting evidence.
Rethinking budgetary slack as budget risk management
Authors: Elmassri Moataz , Harris Elaine
Published: December 2011

Purpose

The purpose of this paper is to draw on a small‐scale study that investigated the relationships between the budget‐setting process and slack, and how budgetary, behavioural and contextual factors can affect this relationship, to reconceptualise the phenomenon of budgetary slack as a budget risk management strategy.

Design/methodology/approach

A case study method was employed, which enabled the researchers to investigate factors suggested by prior literature that affect slack creation. In total, nine structured interviews were conducted in a state‐owned Egyptian petroleum company, which gave the researchers a different way of thinking about the budget slack phenomenon.

Findings

The authors found that slack is created, but not perceived negatively by managers, wherever they are in the organisational hierarchy. Few factors from the literature appeared to have any effect on the creation of budgetary slack, but the covert view of budget slack as a negative behaviour, adopted by early literature was perceived by participants as unethical and inconsistent with Egyptian culture. Managers did not recognise the notion of budgetary slack, though a “contingency” was created and was seen as entirely rational and acceptable by both superiors and subordinates. These findings are consistent with more recent literature in taking a more positive view, and with risk management thinking.

Research limitations/implications

The evidence from this small study in a single organisation obviously cannot be generalised to the whole population. More research is needed in different contexts in order to discover whether managers may perceive this link between budget contingencies and risk management. Also, further research may explore the ethical dimension of behaviour and its possible foundation in religious values and beliefs, to see if this influences how building “contingencies” into budgets is perceived.

Practical implications

If we were to stop portraying the creation of budgetary slack as a negative behaviour and accept that practitioners find it acceptable in managing budgets in an uncertain economic environment, more managers may be open about it.

Originality/value

The main contribution of this paper is that it proposes that what was originally described as a negative behavioural phenomenon be rethought as a positive risk management strategy. Though other authors have viewed budget slack more positively, none has made the explicit link to risk management. The authors reposition budget slack in terms of contingency planning and show how this is consistent with risk management thinking.
Tacit knowledge barriers in franchising: practical solutions
Authors: Cumberland Denise , Githens Rod
Published: December 2011

Purpose

The purpose of this paper is to identify barriers that hinder tacit knowledge transfer in a franchise environment and offer a compendium of solutions that encourage franchisees and franchisors to leverage tacit knowledge as a resource for competitive advantage.

Design/methodology/approach

Drawing from the research on franchise organizations there are five barriers to tacit knowledge transfer that present a challenge to both vertical and horizontal information flow in a franchise environment. It is suggested that when specific behaviors and processes are adopted to encourage sharing tacit knowledge it is possible to reduce tension and promote collaboration in the franchise relationship.

Findings

Barriers to tacit knowledge transfer in franchise organizations include: Trust, Maturation, Communication, Competition, and Culture. Ideas for fostering knowledge sharing are offered.

Research limitations/implications

The factors identified only partially explain why there may be resistance to sharing tacit knowledge between franchisees and franchisors. Solutions recommended will need further testing to assess their impact on creating cultures that embrace tacit knowledge sharing.

Practical implications

For franchisors and franchisees to encourage tacit knowledge sharing they will need to recognize and value what each player contributes to the relationship.

Originality/value

The identification of specific barriers to tacit knowledge transfer in franchise environment sets the stage for future work that can expand on solutions in the franchise context that potentially has economic and psychological benefits for both parties.
The impact of human resource disclosure on corporate image
Authors: Alvarez Dominguez América
Published: December 2011

Purpose

The purpose of this paper is to investigate the effects of human resource disclosure on corporate image.

Design/methodology/approach

The information about human resources presented in their annual reports by 105 Spanish listed companies was grouped in three categories, previously defined in literature. We distinguish information about human capital (items usually included as human capital in Intellectual Capital reports), social information about employees and information about ethics questions relative to employees. A content analysis of these 105 annual reports was conducted to measure human resource disclosure and a regression analysis was carried out to study the impact of this information on company image.

Findings

The findings reflect the significant effect of the three categories of human resource disclosure on corporate image.

Practical implications

This study might encourage firms to improve their disclosure policy on issues related to human capital, such as training, and on social and ethical aspects of employees, such as health and safety at work and working rights.

Originality/value

This paper contributes to research on human resources by confirming the impact not only of information about human capital, which is mainly oriented to shareholders, but of social and ethical information about employees, oriented as well as to stakeholders, on corporate reputation.