bluuebunny/crossref_metadata_2025_split huggingface dataset:
SeekStream: adapting to dynamic user behavior in P2P video‐on‐demand
Authors: Deltouzos Konstantinos , Gkortsilas Ilias , Efthymiopoulos Nikolaos , Efthymiopoulou Maria , Denazis Spyros 
Published: January 2016

SummaryIn recent years, the users' perceived quality of experience (QoE) in streaming services has gained a lot of attention. Particularly, a number of research efforts have focused on providing live streaming and video‐on‐demand (VoD) services using peer‐to‐peer (P2P) architectures. However, in these proposed architectures, the heterogeneity of users and their dynamic behavior has not been sufficiently studied. In a real life scenario, where users have highly heterogeneous bandwidth resources (cable, DSL, 3G networks, etc) and can arbitrarily decide to perform a VCR function (stop, fast forward and seeking), ignoring this behavior can significantly deteriorate the system's efficiency and the perceived QoE. In this paper, we present SeekStream, a scalable P2P VoD architecture that ensures the stable delivery of the video stream to every participating user even in cases of high heterogeneity and frequent seeking operations. Specifically, SeekStream is a set of algorithms that optimize the P2P overlay dynamically and in a distributed fashion, making it adaptive to users dynamic behavior and bandwidth changes. The available bandwidth resources of the participating users are optimally exploited, keeping the contribution from the media server(s) to a minimal level. To illustrate the performance of the proposed algorithms, we are using a centralized overlay network manager that discovers the optimal network graph as a reference. We have developed an extensive P2P VoD simulator that shows the efficiency, scalability, and stability of our system under variant and dynamic conditions. The algorithms of our proposed system introduce less than 4% bandwidth overhead while we achieve high offloading of the media server(s). SeekStream guarantees a high block reception rate for the users, even under extreme seeking patterns. Copyright © 2016 John Wiley & Sons, Ltd.
Temporal and latitudinal trends of p,p′-DDE in eggs and carcasses of North American birds from 1980 to 2005
Authors: Mora Miguel A. , Durgin Bryce , Hudson Lacy B. , Jones Edward 
Published: January 2016

Abstract

The use of 1,1,1-trichloro-2,2-bis(p-chlorophenyl) ethane (DDT) in agriculture in the United States and Canada was prohibited in the early 1970s; however, it continued to be used restrictively in Mexico until 2000. Forty years later, 1,1-dichloro-2,2-bis(p-chlorophenyl) ethylene (p,p′-DDE), continues to be detected in eggs and bird carcasses in North America. The use of DDE has been associated with reproductive failure of several avian species, primarily through eggshell thinning. To assess the temporal and latitudinal distribution of p,p′-DDE in North America, the authors examined DDE concentrations reported in bird tissues in the scientific literature published between 1980 and 2009. Overall, the majority of supported models suggested that DDE concentrations in birds were greater in the upper mid-latitudes (38°–48°) than in other parts of North America. However, spatial trends of DDE seemed to be influenced by regions with large amounts of data, such as the Great Lakes area. Concentrations of p,p′-DDE in eggs averaged 2.5 μg/g, 3.2 μg/g, and 29.5 μg/g wet weight in 1980 and decreased to 1.64 μg/g, 0.87 μg/g, and 1.01 μg/g wet weight by the mid-2000s for the central, eastern, and western North America regions, respectively. The results indicate that, over time, all DDE residues observed in birds have decreased significantly in North America. Environ Toxicol Chem 2016;35:1340–1348. © 2016 SETAC
Productivity changes in OECD healthcare systems: bias‐corrected Malmquist productivity approach
Authors: Kim Younhee , Oh Dong‐hyun , Kang Minah 
Published: January 2016

SummaryThis study evaluates productivity changes in the healthcare systems of 30 Organization for Economic Co‐operation and Development (OECD) countries over the 2002–2012 periods. The bootstrapped Malmquist approach is used to estimate bias‐corrected indices of healthcare performance in productivity, efficiency and technology by modifying the original distance functions. Two inputs (health expenditure and school life expectancy) and two outputs (life expectancy at birth and infant mortality rate) are used to calculate productivity growth. There are no perceptible trends in productivity changes over the 2002–2012 periods, but positive productivity improvement has been noticed for most OECD countries. The result also informs considerable variations in annual productivity scores across the countries. Average annual productivity growth is evenly yielded by efficiency and technical changes, but both changes run somewhat differently across the years. The results of this study assert that policy reforms in OECD countries have improved productivity growth in healthcare systems over the past decade. Countries that lag behind in productivity growth should benchmark peer countries' practices to increase performance by prioritizing an achievable trajectory based on socioeconomic conditions. For example, relatively inefficient countries in this study indicate higher income inequality, corresponding to inequality and health outcomes studies. Although income inequality and globalization are not direct measures to estimate healthcare productivity in this study, these issues could be latent factors to explain cross‐country healthcare productivity for future research. Copyright © 2016 John Wiley & Sons, Ltd.
Cost-Effectiveness of Osteoporosis Screening Strategies for Men
Authors: Nayak Smita , Greenspan Susan L 
Published: January 2016

ABSTRACT

Osteoporosis affects many men, with significant morbidity and mortality. However, the best osteoporosis screening strategies for men are unknown. We developed an individual-level state-transition cost-effectiveness model with a lifetime time horizon to identify the cost-effectiveness of different osteoporosis screening strategies for US men involving various screening tests (dual-energy X-ray absorptiometry [DXA]; the Osteoporosis Self-Assessment Tool [OST]; or a fracture risk assessment strategy using age, femoral neck bone mineral density [BMD], and Vertebral Fracture Assessment [VFA]); screening initiation ages (50, 60, 70, or 80 years); and repeat screening intervals (5 years or 10 years). In base-case analysis, no screening was a less effective option than all other strategies evaluated; furthermore, no screening was more expensive than all strategies that involved screening with DXA or the OST risk assessment instrument, and thus no screening was “dominated” by screening with DXA or OST at all evaluated screening initiation ages and repeat screening intervals. Screening strategies that most frequently appeared as most cost-effective in base-case analyses and one-way sensitivity analyses when assuming willingness-to-pay of $50,000/quality-adjusted life-year (QALY) or $100,000/QALY included screening initiation at age 50 years with the fracture risk assessment strategy and repeat screening every 10 years; screening initiation at age 50 years with fracture risk assessment and repeat screening every 5 years; and screening initiation at age 50 years with DXA and repeat screening every 5 years. In conclusion, expansion of osteoporosis screening for US men to initiate routine screening at age 50 or 60 years would be expected to be effective and of good value for improving health outcomes. A fracture risk assessment strategy using variables of age, femoral neck BMD, and VFA is likely to be the most effective of the evaluated strategies within accepted cost-effectiveness parameters. DXA and OST are also reasonable screening options, albeit likely slightly less effective than the evaluated fracture risk assessment strategy. © 2016 American Society for Bone and Mineral Research.
TSC‐22 Promotes Interleukin‐2‐Deprivation Induced Apoptosis in T‐Lymphocytes
Authors: Pépin Aurélie , Espinasse Marie‐Alix , Latré de Laté Perle , Szely Natacha , Pallardy Marc , Biola‐Vidamment Armelle 
Published: January 2016

ABSTRACTOriginally described as a TGF‐β‐inducible gene, tsc‐22 (Transforming growth factor‐beta Stimulated Clone 22) encodes a transcriptional regulator affecting biological processes such as cell growth, differentiation, or apoptosis. Along with GILZ (Glucocorticoid‐Induced Leucine Zipper), TSC‐22 belongs to the evolutionary conserved TSC‐22 Domain family. We previously showed that, in T‐lymphocytes, GILZ expression was induced upon IL‐2 withdrawal, delaying apoptosis through down‐regulation of the pro‐apoptotic protein BIM expression. The aim of this work was then to elucidate the respective roles of GILZ and TSC‐22 upon IL‐2 deprivation‐induced apoptosis. We report here that these two highly homologous genes are concomitantly expressed in most human tissues and in primary T‐lymphocytes and that expression of TSC‐22 promotes T‐lymphocytes apoptosis by inhibiting GILZ functions. Indeed, we demonstrated that TSC‐22 expression in the murine lymphoid CTLL‐2 cell line promoted IL‐2 deprivation‐induced apoptosis. BIM expression and caspases‐9 and ‐3 activities were markedly increased in TSC‐22 expressing clones compared to control clones. Analysis of GILZ expression revealed that TSC‐22 prevented the induction of the GILZ protein upon IL‐2 deprivation, by inhibiting gilz mRNA transcription. These results suggested that TSC‐22 could counteract the protective effect of GILZ on IL‐2‐deprivation‐induced apoptosis. Moreover, TSC‐22‐induced inhibition of GILZ expression was also found in CTLL‐2 cells treated with glucocorticoids or TGF‐β. In the human NKL cell line deprived of IL‐2, TSC‐22 showed the same effect and thus may represent a potent repressor of GILZ expression in IL‐2‐dependent cells, independently of the cell type, or the stimulus, leading to an increase of IL‐2‐deprived T‐cells apoptosis. J. Cell. Biochem. 117: 1855–1868, 2016. © 2016 Wiley Periodicals, Inc.
Shifted power method for computing tensor H‐eigenpairs
Authors: Lu Yinbing , Pan Jianyu 
Published: January 2016

SummaryIn this paper, we propose a shifted symmetric higher‐order power method for computing the H‐eigenpairs of a real symmetric even‐order tensor. The local convergence of the method is proved. In addition, by utilizing the fixed‐point analysis, we can characterize exactly which H‐eigenpairs can be found and which cannot be found by the method. Numerical examples are presented to illustrate the performance of the method. Copyright © 2016 John Wiley & Sons, Ltd.
Flavonoids from the flowers of Impatiens glandulifera Royle isolated by high performance countercurrent chromatography
Authors: Vieira Mariana N. , Winterhalter Peter , Jerz Gerold 
Published: January 2016

AbstractIntroductionImpatiens glandulifera Royle (Balsaminaceae) is an annual herb from the Himalaya region, currently widespread along European river systems and one of the most important neophyte invading plants in Germany. Exploring the effects of allelopathic plant chemicals is important for the understanding of its ecological impacts in the process of suppression of indigenous plant species.ObjectiveTo investigate the chemical composition of Impatiens glandulifera flowers (IGFs) using high performance countercurrent chromatography (HPCCC).MethodsThe flowers of Impatiens glandulifera were manually separated and extracted with ethanol. LC‐ESI‐MS/MS was used to characterise the crude extract of IGF. The various flavonoids detected were isolated by HPCCC using of methyl tert‐butyl ether–acetonitrile–water (2:2:3, v/v/v). The combination of the data provided by preparative ESI‐MS/MS metabolite profiling, LC‐ESI‐MS/MS, UV‐vis and 1D/2D‐NMR spectroscopic analysis was used to elucidate the structures of the isolated compounds.ResultsHPCCC runs led to the direct isolation of pure dihydromyricetin (ampelopsin), eriodictyol‐7‐O‐glucoside, kaempferol‐3‐O‐glucoside (astragalin) and kaempferol‐3‐O‐6ʺ‐malonyl‐glucoside, as well as the pre‐purification of kaempferol‐3‐O‐rhamno‐rhamnosyldiglucoside, quercetin‐3‐O‐galactoside (hyperoside), quercetin and kaempferol in a single step.ConclusionThis is the first report on the flavonoid composition of the species Impatiens glandulifera. The developed protocol was successfully used to isolate the main flavonoids from the crude extract of IGFs. This combined HPCCC and HPLC procedure could be applied to the fast fractionation and recovery of flavonoid derivatives of other plant extracts. Copyright © 2016 John Wiley & Sons, Ltd.
Comparison of curved root canals preparation using reciprocating, continuous and an association of motions
Authors: Hoppe Carolina Bender , Böttcher Daiana Elisabeth , Justo Aline Martins , Só Marcus Vinícius Reis , Grecca Fabiana Soares 
Published: January 2016

SummaryThe aim of this study was to compare the rotary ProTaper Universal system, the single‐file reciprocating WaveOne system and an association of motions assessing shaping ability, cleanliness, preparation time and instrument failures after preparation of curved root canals. Sixty root canals of extracted human molar teeth, with curvatures ranging between 20° and 40°, were divided into three groups, according with preparation system. Canals were prepared until apical size 25 using the ProTaper Universal system (G1), WaveOne (G2), or a hybrid technique (G3) associating reciprocating preparation with rotary glide path and cervical pre‐enlargement. Teeth were scanned pre and post‐operatively using computed tomography. Direction of transportation and centering ability of canals were measured using a computer image analysis program, and the results were analyzed statistically using one‐way ANOVA. Preparation time was analyzed by one‐way ANOVA and the Tukey post hoc test. Instrument failures were recorded. The amounts of debris and smear layer were quantified based on a numerical evaluation scale by scanning electron microscopy and were analyzed statistically using the Kruskal–Wallis test. No difference in transportation and centering ratio was found between the systems. Instrumentation with WaveOne was significantly faster than with other instruments (p < 0.05). During preparation, no instruments fractured and three suffered deformations. For debris removal and remaining smear layer, the results for the three groups were similar. The single‐file reciprocating instrument was capable of providing faster root canal preparation with similar transporting, centralization and cleaning ability when compared with continuous and an association of motions in curved canals. SCANNING 38:462–468, 2016. © 2016 Wiley Periodicals, Inc.
Quantitative analysis of the cell‐surface roughness and viscoelasticity for breast cancer cells discrimination using atomic force microscopy
Authors: Wang Yuhua , Xu Chaoxian , Jiang Ningcheng , Zheng Liqin , Zeng Jinshu , Qiu Caimin , Yang Hongqin , Xie Shusen 
Published: January 2016

SummaryBreast cancer has been one of the most common malignant tumors threatening female health with high incidence. Cell mechanics is becoming an important issue and could serves as a potential indicator for early cancer diagnosis. In this study, atomic force microscopy (AFM) was applied to characterize and compare the surface nanostructure and viscoelasticity of different breast cell lines. Our results show that breast cancerous cells MCF‐7 exhibit more disorganized filamentous cytoskeleton structure with increased membrane roughness compared to benign breast cells MCF‐10A (P < 0.05). The viscoelastic properties, including elasticity and viscosity, are significantly different between the two cell lines. MCF‐7 displays reduced elasticity and viscosity, indicating that breast cancer cells are softer and more fluid than benign counterpart. Our findings provide new insights into the biophysical changes of cells during tumor transformation and suggest it could be used for early cancer detection at single cell level. SCANNING 38:558–563, 2016. © 2016 Wiley Periodicals, Inc.
Cryptanalysis and improvement of a chaotic maps‐based anonymous authenticated key agreement protocol for multiserver architecture
Authors: Lu Yanrong , Li Lixiang , Peng Haipeng , Yang Yixian 
Published: January 2016

AbstractWith the purpose of ensuring secure communication through wireless environments, authenticated key agreement protocols with user anonymity are widely investigated. Inspired by the semi‐group property of Chebyshev maps and multiple servers in the network environment, Tsai et al. proposed a novel chaotic maps‐based anonymous authenticated key agreement protocol based on multiserver architecture. Unfortunately, we observe that the Tsai et al. protocol falls to key‐compromise impersonation attack, which opens the door for an attacker to launch an offline password‐guessing attack. Moreover, the Tsai et al. protocol also unfortunately violates the session key security. Elaborating on the security of chaotic maps‐based authenticated key agreement, we present an enhanced protocol employing biometrics that attempts to repair the security pitfalls found in Tsai et al. Security analysis shows that the enhanced protocol satisfies more security attributes while retaining the merits of the original protocol. We also present a formal proof of the enhanced protocol with the Burrows–Abadi–Needham logic. The performance of our protocol is evaluated with its predecessor protocols, and the comparative results show that it outperforms the predecessor protocols in terms of better trade‐off between desirable security attributes and computational overhead. Copyright © 2016 John Wiley & Sons, Ltd.
Surgical and Survival Outcome Following Truly Palliative Gastrectomy in Patients with Incurable Gastric Cancer
Authors: Tokunaga Masanori , Makuuchi Rie , Miki Yuichiro , Tanizawa Yutaka , Bando Etsuro , Kawamura Taiichi , Terashima Masanori 
Published: January 2016

AbstractBackground and objectivesGastrectomy is sometimes performed even in patients with incurable factors, particularly when they have urgent symptoms. The aim of this study was to clarify the clinicopathological characteristics of patients undergoing palliative gastrectomy and to identify prognostic factors.MethodsThis study included consecutive 137 gastric cancer patients with urgent symptoms who underwent gastrectomy with macroscopic residual tumor at Shizuoka Cancer Center. Clinicopathological characteristics and surgical outcomes were investigated. In addition, we used the Cox proportional hazards model to identify independent prognostic factors.ResultsOf 137 patients, urgent symptoms were bleeding in 58 patients and stenosis in 112 patients. Postoperative complications were observed in 58 patients (42 %). Chemotherapy was given after surgery in 94 patients (70 %). Median survival time for all patients was 9.9 months, and was longer in patients receiving chemotherapy (11.1 months) than in those not receiving chemotherapy (6.8 months; p = 0.002). Multivariate analysis identified macroscopic type (hazard ratio, 0.471; 95 % confidence interval, 0.364–0.927) as an independent prognostic factor.ConclusionsThe postoperative complication rate was high and survival outcome was poor in patients undergoing palliative gastrectomy. Postoperative chemotherapy may carry a better survival outcome, so we should try to give chemotherapy after palliative gastrectomy.
Les fistules péniennes urétrocutanées postcirconcision: à propos de 85 cas
Authors: Sow Y. , Diao B. , Tfeil Y. O. , Fall P. A. , Fall B. , Kabore A. F. , Ndoye A. K. H. , Diagne B. A. 
Published: January 2016

Résumé

Buts
Analyser les aspects cliniques et thérapeutiques des cas de fistules péniennes liés à une circoncision et pris en charge dans notre pratique quotidienne urologique.

Patients et méthodes
Étude rétrospective des dossiers des patients admis pour fistule pénienne postcirconcision de la période allant de 1990 à 2007.

Résultats
Quatre-vingt-cinq cas ont été notés avec une moyenne d’âge de 10,7 ans (15 mois et 38 ans). La circoncision était réalisée par un personnel paramédical dans la majorité des cas. Le délai de consultation était en moyenne de 4,1 ± 5,3 ans (1 semaine-28 ans). La fistule était associée à une amputation partielle du gland dans un cas et une sténose du méat urétral dans trois cas. Le traitement chirurgical a consisté surtout à un dédoublement urétrocutané. Avec un recul moyen de 3,35 ans (2 mois-8 ans), nous avions noté 81,2 % de bons résultats.

Conclusion
La fistule pénienne postcirconcision est fréquente dans nos régions. Sa prise en charge est assez codifiée, mais le risque d’échec n’est pas négligeable, d’oú l’intérêt de la prévention.
Profil épidémiologique et clinique de l’infertilité masculine à l’hôpital général de Grand-Yoff, Sénégal: à propos de 492 cas
Authors: Niang L. , Ndoye M. , Labou I. , Jalloh M. , Kane R. , Diaw J. J. , Ndiaye A. , Guèye S. M. 
Published: January 2016

Résumé

Objectif
Décrire le profil général de l’infertilité masculine, au Sénégal, en milieu hospitalier.

Matériels et méthodes
Il s’agit d’une étude rétrospective, descriptive, portant sur 492 dossiers de patients vus en consultation pour infertilité conjugale du couple entre 2000 et 2004. L’ensemble des paramètres étudiés portait sur les éléments cliniques et les explorations paracliniques.

Résultats
L’âge moyen des patients était de 39 ans. La durée d’évolution de l’infertilité était en moyenne de six ans. L’infertilité était de type primaire dans 66,5 % des cas. Sur le plan clinique, la varicocèle était l’anomalie la plus souvent retrouvée, soit dans 64,6 % des cas. Le spermogramme était perturbé dans 84,3 % des cas. Les principales perturbations étaient une oligospermie inférieure à 5 millions de spermatozoïes/ml (35,6 %) et une azoospermie dans 28,6 % des cas.

Conclusion
Le profil général de l’infertilité est polymorphe. L’exploration est limitée par la non-disponibilité de la partenaire et l’absence de coordination entre gynécologues et andrologues. L’amélioration de la prise en charge de l’infertilité doit passer par de nouvelles voies de recherche, notamment génétiques et immunologiques, afin d’identifier les causes habituellement cachées de l’infertilité. Elle doit aussi reposer sur une bonne collaboration entre praticiens de santé de la reproduction et la mise en place d’unités d’assistance médicale à la procréation (AMP).