bluuebunny/crossref_metadata_2025_split huggingface dataset:
MULTI-ARMED BANDITS UNDER GENERAL DEPRECIATION AND COMMITMENT
Authors: Cowan Wesley , Katehakis Michael N. 
Published: October 2014

Generally, the multi-armed has been studied under the setting that at each time step over an infinite horizon a controller chooses to activate a single process or bandit out of a finite collection of independent processes (statistical experiments, populations, etc.) for a single period, receiving a reward that is a function of the activated process, and in doing so advancing the chosen process. Classically, rewards are discounted by a constant factor β∈(0, 1) per round.In this paper, we present a solution to the problem, with potentially non-Markovian, uncountable state space reward processes, under a framework in which, first, the discount factors may be non-uniform and vary over time, and second, the periods of activation of each bandit may be not be fixed or uniform, subject instead to a possibly stochastic duration of activation before a change to a different bandit is allowed. The solution is based on generalized restart-in-state indices, and it utilizes a view of the problem not as “decisions over state space” but rather “decisions over time”.
Progressive increase in community-associated methicillin-resistant Staphylococcus aureus in Indigenous populations in northern Australia from 1993 to 2012
Authors: TONG S. Y. C. , VARRONE L. , CHATFIELD M. D. , BEAMAN M. , GIFFARD P. M. 
Published: October 2014

SUMMARYHospital-based studies have determined high rates of community-associated methicillin-resistant Staphylococcus aureus (MRSA) in Indigenous populations. However, there is a paucity of community-based data. We obtained 20 years (1993–2012) of data on S. aureus isolates (N = 20 210) collected from community clinics that provide services for Indigenous communities in the Northern Territory, Australia. Methicillin resistance increased from 7% to 24%, resistance to macrolides remained stable at ~25%, and there was a slight increase in resistance to trimethoprim-sulfamethoxazole. The increase in methicillin resistance is concerning for the Indigenous communities represented by this data, but it is also of significance if virulent MRSA clones emerge and spread more widely from such settings.
Revisiting N2 fixation in Guerrero Negro intertidal microbial mats with a functional single-cell approach
Authors: Woebken Dagmar , Burow Luke C , Behnam Faris , Mayali Xavier , Schintlmeister Arno , Fleming Erich D , Prufert-Bebout Leslie , Singer Steven W , Cortés Alejandro López , Hoehler Tori M , Pett-Ridge Jennifer , Spormann Alfred M , Wagner Michael , Weber Peter K , Bebout Brad M 
Published: October 2014

Abstract
Photosynthetic microbial mats are complex, stratified ecosystems in which high rates of primary production create a demand for nitrogen, met partially by N2 fixation. Dinitrogenase reductase (nifH) genes and transcripts from Cyanobacteria and heterotrophic bacteria (for example, Deltaproteobacteria) were detected in these mats, yet their contribution to N2 fixation is poorly understood. We used a combined approach of manipulation experiments with inhibitors, nifH sequencing and single-cell isotope analysis to investigate the active diazotrophic community in intertidal microbial mats at Laguna Ojo de Liebre near Guerrero Negro, Mexico. Acetylene reduction assays with specific metabolic inhibitors suggested that both sulfate reducers and members of the Cyanobacteria contributed to N2 fixation, whereas 15N2 tracer experiments at the bulk level only supported a contribution of Cyanobacteria. Cyanobacterial and nifH Cluster III (including deltaproteobacterial sulfate reducers) sequences dominated the nifH gene pool, whereas the nifH transcript pool was dominated by sequences related to Lyngbya spp. Single-cell isotope analysis of 15N2-incubated mat samples via high-resolution secondary ion mass spectrometry (NanoSIMS) revealed that Cyanobacteria were enriched in 15N, with the highest enrichment being detected in Lyngbya spp. filaments (on average 4.4 at% 15N), whereas the Deltaproteobacteria (identified by CARD-FISH) were not significantly enriched. We investigated the potential dilution effect from CARD-FISH on the isotopic composition and concluded that the dilution bias was not substantial enough to influence our conclusions. Our combined data provide evidence that members of the Cyanobacteria, especially Lyngbya spp., actively contributed to N2 fixation in the intertidal mats, whereas support for significant N2 fixation activity of the targeted deltaproteobacterial sulfate reducers could not be found.
Nanosecond light induced, thermally tunable transient dual absorption bands in a-Ge5As30Se65 thin film
Authors: Khan Pritam , Saxena Tarun , Jain H. , Adarsh K. V. 
Published: October 2014

AbstractIn this article, we report the first observation of nanosecond laser induced transient dual absorption bands, one in the bandgap (TA1) and another in the sub-bandgap (TA2) regions of a-Ge5As30Se65 thin films. Strikingly, these bands are thermally tunable and exhibit a unique contrasting characteristic: the magnitude of TA1 decreases while that of TA2 increases with increasing temperature. Further, the decay kinetics of these bands is strongly influenced by the temperature, which signifies a strong temperature dependent exciton recombination mechanism. The induced absorption shows quadratic and the decay time constant shows linear dependence on the laser beam fluence.
Metformin and respiratory chain complex I: the last piece of the puzzle?
Authors: Fontaine Eric 
Published: October 2014

Metformin is the most widely prescribed drug used to treat patients affected by Type 2 diabetes. Metformin has also been shown to prevent some forms of cell death; however, evidence suggests that it may have anti-neoplastic properties. All of these effects have been attributed to complex I inhibition, but the mechanism by which metformin leads to complex I inhibition is not fully understood. Although it has been reported that the incubation of functionally isolated complex I in the presence of high concentrations of metformin led to its inhibition, much lower concentrations of metformin have been shown to inhibit complex I in intact cells. In a recent issue of the Biochemical Journal, Bridges, Jones, Pollak and Hirst [(2014) Biochem. J. 462, 475–487] studied for the first time the effect of metformin on purified complex I. They report that millimolar concentrations of metformin directly inhibit complex I activity in a non-competitive manner. They also specify that the binding of metformin to complex I depends on its conformation. To explain the difference in concentration required to inhibit complex I in intact cells and on isolated enzyme, Bridges et al. (2014) propose that metformin concentrates within mitochondria in intact cells. Albeit theoretically plausible, this attractive hypothesis is not directly tested by Bridges et al. (2014) Moreover, although sparse, the current literature does not support this hypothesis.
Vascular smooth muscle cell proliferation depends on caveolin-1-regulated polyamine uptake
Authors: Grossi Mario , Rippe Catarina , Sathanoori Ramasri , Swärd Karl , Forte Amalia , Erlinge David , Persson Lo , Hellstrand Per , Nilsson Bengt-Olof 
Published: October 2014

Much evidence highlights the importance of polyamines for VSMC (vascular smooth muscle cell) proliferation and migration. Cav-1 (caveolin-1) was recently reported to regulate polyamine uptake in intestinal epithelial cells. The aim of the present study was to assess the importance of Cav-1 for VSMC polyamine uptake and its impact on cell proliferation and migration. Cav-1 KO (knockout) mouse aortic cells showed increased polyamine uptake and elevated proliferation and migration compared with WT (wild-type) cells. Both Cav-1 KO and WT cells expressed the smooth muscle differentiation markers SM22 and calponin. Cell-cycle phase distribution analysis revealed a higher proportion of Cav-1 KO than WT cells in the S phase. Cav-1 KO cells were hyper-proliferative in the presence but not in the absence of extracellular polyamines, and, moreover, supplementation with exogenous polyamines promoted proliferation in Cav-1 KO but not in WT cells. Expression of the solute carrier transporters Slc7a1 and Slc43a1 was higher in Cav-1 KO than in WT cells. ODC (ornithine decarboxylase) protein and mRNA expression as well as ODC activity were similar in Cav-1 KO and WT cells showing unaltered synthesis of polyamines in Cav-1 KO cells. Cav-1 was reduced in migrating cells in vitro and in carotid lesions in vivo. Our data show that Cav-1 negatively regulates VSMC polyamine uptake and that the proliferative advantage of Cav-1 KO cells is critically dependent on polyamine uptake. We provide proof-of-principle for targeting Cav-1-regulated polyamine uptake as a strategy to fight unwanted VSMC proliferation as observed in restenosis.
Modified Posterior Lumbar Interbody Fusion for Radiculopathy following Healed Vertebral Collapse of the Middle-Lower Lumbar Spine
Authors: Yamashita Tomoya , Sakaura Hironobu , Miwa Toshitada , Ohwada Tetsuo 
Published: October 2014

Study Design Retrospective study. Objectives Lumbar radiculopathy is rarely observed in patients who have achieved bony healing of vertebral fractures in the middle-lower lumbar spine. The objectives of the study were to clarify the clinical features of such radiculopathy and to evaluate the preliminary outcomes of treatment using a modified posterior lumbar interbody fusion (PLIF) procedure. Methods Fourteen patients with at least 2-year follow-up were enrolled in this study. The radiologic and clinical features of radiculopathy were retrospectively reviewed. As part of our modified PLIF procedure, a bone block was laid on chipped bone to fill the cavity of the fractured end plate and to flatten the cage–bone interface. Results The morphologic features of spinal deformity in our patients typically consisted of the intradiscal vacuum phenomenon, spondylolisthesis, and a retropulsed intervertebral disk with a vertebral rim in the damaged segment. Cranial end plate fracture resulted in radiculopathy of the traversing nerve roots due to lateral recess stenosis. On the other hand, caudal end plate fracture led to unilateral radiculopathy of the exiting nerve root due to foraminal stenosis. The mean recovery rate based on the Japanese Orthopaedic Association score was 65.0%. Solid fusion was achieved in all but one case. Conclusions Because of severe deterioration of the anterior column following end plate fracture, the foraminal zone must be decompressed in caudal end plate fractures. The modified PLIF procedure yielded satisfactory clinical outcomes due to anterior reconstruction and full decompression for both foraminal and lateral recess stenoses.
Intradural Neurocysticercosis of Lumbar Spine: A Case Report
Authors: Ganesan Sudhir , Acharya Shankar , Kalra K. L. , Chahal Rupinder 
Published: October 2014

Study Design Case report. Objective Cysticercosis (parasitic infection caused by Taenia solium) is the most common parasitic infection of the nervous system. However, spinal neurocysticercosis is rare. It can present as an extraspinal or intraspinal lesion, with intramedullary being the rarest location. The symptoms can vary from vague backache and radiculopathy to cauda equine syndrome. Methods We report a 32-year-old man who presented with neurocysticercosis in the lumbar spine and cauda equine syndrome. He had low backache for 1 month, hesitancy in micturition, and decreased perianal sensation for the previous 2 days. Magnetic resonance imaging revealed an intradural extramedullary lesion extending from L2–S1 that was hyperintense in T2- and hypointense in T1-weighted images. Results Because the patient presented with cauda equine syndrome, urgent decompressive laminectomy was done from L2–S1, and the thin-walled cysts with clear fluid were removed. Histopathologic examination confirmed neurocysticercosis. The perianal sensation and the bladder control recovered completely. Conclusion Neurocysticercosis should be considered in the differential diagnosis in patients presenting with a similar picture, and urgent surgical decompression should be attempted to prevent further worsening of the neurologic symptoms.
Fixed Sagittal Plane Imbalance
Authors: Savage Jason W. , Patel Alpesh A. 
Published: October 2014

Study Design Literature review. Objective To discuss the evaluation and management of fixed sagittal plane imbalance. Methods A comprehensive literature review was performed on the preoperative evaluation of patients with sagittal plane malalignment, as well as the surgical strategies to address sagittal plane deformity. Results Sagittal plane imbalance is often caused by de novo scoliosis or iatrogenic flat back deformity. Understanding the etiology and magnitude of sagittal malalignment is crucial in realignment planning. Objective parameters have been developed to guide surgeons in determining how much correction is needed to achieve favorable outcomes. Currently, the goals of surgery are to restore a sagittal vertical axis < 5 cm, pelvic tilt < 20 degrees, and lumbar lordosis equal to pelvic incidence ± 9 degrees. Conclusion Sagittal plane malalignment is an increasingly recognized cause of pain and disability. Treatment of sagittal plane imbalance varies according to the etiology, location, and severity of the deformity. Fixed sagittal malalignment often requires complex reconstructive procedures that include osteotomy correction. Reestablishing harmonious spinopelvic alignment is associated with significant improvement in health-related quality-of-life outcome measures and patient satisfaction.
Is Polymethyl Methacrylate a Viable Option for Salvaging Lateral Mass Screw Failure in the Subaxial Cervical Spine?
Authors: Gallizzi Michael A. , Kuhns Craig A. , Jenkins Tyler J. , Pfeiffer Ferris M. 
Published: October 2014

Study Design Biomechanical analysis of lateral mass screw pullout strength. Objective We compare the pullout strength of our bone cement–revised lateral mass screw with the standard lateral mass screw. Methods In cadaveric cervical spines, we simulated lateral mass screw “cutouts” unilaterally from C3 to C7. We salvaged fixation in the cutout side with polymethyl methacrylate (PMMA) or Cortoss cement (Orthovita, Malvern, Pennsylvania, United States), allowed the cement to harden, and then drilled and placed lateral mass screws back into the cement-augmented lateral masses. On the contralateral side, we placed standard lateral mass screws into the native, or normal lateral, masses and then compared pullout strength of the cement-augmented side to the standard lateral mass screw. For pullout testing, each augmentation group was fixed to a servohydraulic load frame and a specially designed pullout fixture was attached to each lateral mass screw head. Results Quick-mix PMMA-salvaged lateral mass screws required greater force to fail when compared with native lateral mass screws. Cortoss cement and PMMA standard-mix cement-augmented screws demonstrated less strength of fixation when compared with control-side lateral mass screws. Attempts at a second round of cement salvage of the same lateral masses led to more variations in load to failure, but quick-mix PMMA again demonstrated greater load to failure when compared with the nonaugmented control lateral mass screws. Conclusion Quick-mix PMMA cement revision equips the spinal surgeon with a much needed salvage option for a failed lateral mass screw in the subaxial cervical spine.
Biotin-deficient diet induces chromosome misalignment and spindle defects in mouse oocytes
Authors: Tsuji Ai , Nakamura Toshinobu , Shibata Katsumi 
Published: October 2014

Abstract
Increased abnormal oocytes due to meiotic chromosome misalignment and spindle defects lead to elevated rates of infertility, miscarriage, and trisomic conceptions. Here, we investigated the effect of biotin deficiency on oocyte quality. Three-week-old female ICR mice were fed a biotin-deficient or control diet (0, 0.004 g biotin/kg diet) for 21 days. On day 22, these mouse oocytes were analyzed by immunofluorescence. Due to biotin, undernutrition increased the frequency of abnormal oocytes (the biotin deficient vs. control: 40 vs. 16%). Next, the remaining mice in the biotin-deficient group were fed a control or biotin-deficient diet from day 22 to 42. Although biotin nutritional status in the recovery group was restored, the frequency of abnormal oocytes in the recovery group was still higher than that in the control group (48 vs. 18%). Our results indicate that steady, sufficient biotin intake is required for the production of high-quality oocytes in mice.
Species delimitation and phylogeny estimation under the multispecies coalescent
Authors: Jones Graham 
Published: October 2014

AbstractThis article describes a Bayesian method for inferring both species delimitations and species trees under the multispecies coalescent model using DNA sequences from multiple loci. The focus here is on species delimitation with no a priori assignment of individuals to species, and no guide tree. The method uses a new model for the population sizes along the branches of the species tree, and three new operators for sampling from the posterior using the Markov chain Monte Carlo (MCMC) algorithm. The correctness of the moves is demonstrated both by proofs and by tests of the implementation. Current practice, using a pipeline approach to species delimitation under the multispecies coalescent, has been shown to have major problems on simulated data [10]. The same simulated data set is used to demonstrate the accuracy and efficiency of the present method. The method is implemented in a package called STACEY for BEAST2.
Disruption of the CYTOCHROME C OXIDASE DEFICIENT1 Gene Leads to Cytochrome c Oxidase Depletion and Reorchestrated Respiratory Metabolism in Arabidopsis
Authors: Dahan Jennifer , Tcherkez Guillaume , Macherel David , Benamar Abdelilah , Belcram Katia , Quadrado Martine , Arnal Nadège , Mireau Hakim 
Published: October 2014

Abstract
Cytochrome c oxidase is the last respiratory complex of the electron transfer chain in mitochondria and is responsible for transferring electrons to oxygen, the final acceptor, in the classical respiratory pathway. The essentiality of this step makes it that depletion in complex IV leads to lethality, thereby impeding studies on complex IV assembly and respiration plasticity in plants. Here, we characterized Arabidopsis (Arabidopsis thaliana) embryo-lethal mutant lines impaired in the expression of the CYTOCHROME C OXIDASE DEFICIENT1 (COD1) gene, which encodes a mitochondria-localized PentatricoPeptide Repeat protein. Although unable to germinate under usual conditions, cod1 homozygous embryos could be rescued from immature seeds and developed in vitro into slow-growing bush-like plantlets devoid of a root system. cod1 mutants were defective in C-to-U editing events in cytochrome oxidase subunit2 and NADH dehydrogenase subunit4 transcripts, encoding subunits of respiratory complex IV and I, respectively, and consequently lacked cytochrome c oxidase activity. We further show that respiratory oxygen consumption by cod1 plantlets is exclusively associated with alternative oxidase activity and that alternative NADH dehydrogenases are also up-regulated in these plants. The metabolomics pattern of cod1 mutants was also deeply altered, suggesting that alternative metabolic pathways compensated for the probable resulting restriction in NADH oxidation. Being the first complex IV-deficient mutants described in higher plants, cod1 lines should be instrumental to future studies on respiration homeostasis.
Etihad Airlines: growth through successful strategic partnerships
Authors: Al Ali Hamad A. , Ahmad Syed Zamberi 
Published: October 2014

Subject area
International business and/or strategic management.

Study level/applicability
This case is useful for undergraduate and postgraduate level students majoring in international business management and/or strategic management.

Case overview
Etihad Airways was established in 2003, in Abu Dhabi, United Arab Emirates (UAE) with the UAE government as sole owner. It is the national carrier of UAE with Abu Dhabi as its centre of operations. Etihad is recognized as a fast-growing player in the aviation industry, and has become one of the dominant international players in the industry in a relatively short time. Etihad's fleet now contains more than 67 planes, with more than 1,300 flights per week to diverse destinations across the Middle East, Africa, Europe, Asia, Australia and North America. The company describes its business strategy as “sustainable growth”. Looking through a practitioner's lens, strategic partnerships have been the critical activities through which Etihad has delivered its strategy. The purpose of this case study is therefore to elaborate on its major and successful partnerships and the critical benefits of these. Secondary data were collected from credible sources including academic studies, relevant Etihad publications and industry reports published by official aviation associations.

Expected learning outcomes
Students will be able to understand the theory of strategic partnerships, their roles and benefits and critically evaluate the pre-staging “requirements” of such partnerships. In this case, the specific learning outcome of it is to help students to understand the importance of successful strategic partnerships for Etihad Airlines and how partnership strategies can improve the performance of Etihad Airlines.

Supplementary materials
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