bluuebunny/crossref_metadata_2025_split huggingface dataset:
Statut symbiotique et souches de rhizobia associées à l’Acacia tortilissubsp.raddiana[Acacia raddianas. s.], mimosoïdée des régions désertiques de l’Algérie
Authors: Noureddine Nazhat-Ezzaman , Amrani Saïd , Aïd Fatiha 
Published: February 2010

L’ Acacia tortilis (Forsskal) Hayne subsp. raddiana (Savi) Brenan [ Acacia raddiana Savi s. s.] est la légumineuse ligneuse la plus répandue dans les régions désertiques d’Algérie. En tant qu’espèce bien adaptée, elle offre un potentiel d’intérêt pour le boisement ou le reboisement de ces régions. Sa capacité d’établir une symbiose fixatrice d’azote avec les rhizobia constitue un caractère important pour son développement et son adaptation aux conditions du milieu. Pour ces raisons, nous avons mené une étude portant sur la prévalence de la symbiose chez cette espèce et sur la caractérisation des souches de rhizobia associées. L’étude a porté sur 101 plants provenant de neuf sites naturels et de huit pépinières et nous a permis d’établir que l’A. tortilis subsp. raddiana est généralement nodulé et fixateur d’azote, malgré les conditions édaphiques défavorables qui prévalent en milieu naturel et dans les pépinières du sud du pays. La caractérisation symbiotique de 51 souches de rhizobia associées à l’A. tortilis subsp. raddiana nous a permis de montrer que celles-ci ne sont pas très spécifiques et qu’elles sont capables, pour la plupart, de former des nodules fixateurs d’azote chez les autres espèces d’acacias des régions désertiques de l’Algérie, en particulier l’ Acacia seyal Del. et l’ Acacia ehrenbergiana Hayne. Ces souches représentent donc un potentiel pour la production d’inoculants destinés à la bactérisation de l’A. tortilis subsp. raddiana, mais également des autres espèces d’acacias. L’analyse des profils de restriction du gène de l’ARN 16S des souches de rhizobia associées a permis de mettre en évidence leur grande diversité. Elles étaient représentées essentiellement par les espèces du genre Ensifer avec une prédominance de l’ Ensifer meliloti et, dans une moindre mesure, par des espèces des genres Mesorhizobium et Rhizobium , comme cela a déjà été rapporté par de nombreux auteurs dans d’autres régions d’Afrique. En plus des espèces de rhizobia reconnues comme étant capables de s’associer avec l’A. tortilis raddiana, nous avons isolé cinq souches que nous n’avons pas pu identifier, par réaction en chaîne de la polymérase – polymorphisme de la longueur du fragment de restriction du gène de l’ARN 16S, et qui pourraient constituer une nouvelle espèce génotypique.
Climate Change: The Political Economy of Kyoto Flexible Mechanisms
Authors: Vlachou Andriana , Konstantinidis Charalampos 
Published: February 2010

The Kyoto Protocol entered into force on February 16, 2005. Emissions reductions targets established by the protocol will be met by domestic policies and by three international flexible mechanisms: clean development, joint implementation, and emissions trading. Following a value-theoretic and class-based approach, the purpose of this paper is to analyze these flexible mechanisms. In particular, the paper investigates the nature and adoption of flexible mechanisms, and their class and environmental links and implications. Carbon-intensive capitalist firms and developed economies are found to be exerting great influence on the shaping and implementation of flexible mechanisms. Environmental effectiveness and justice, and equal sustainable development raised and claimed by worker-citizens, social movements, local communities, and developing countries have not been secured. Thus flexible mechanisms do not present a real challenge to current institutions and practices for sustainable climate conditions for the workers-citizen of the world. JEL classification: B5, P1, Q4
Confronting Neoclassical Myths about Self-employment in Latin America
Authors: Montes-Rojas Gabriel V. 
Published: February 2010

This article analyzes the nature of micro-entrepreneurship in Argentina and relates it to the empirical evidence available for other Latin American countries. It focuses on whether the sector resembles the neoclassical view, characterized by the risk-taking nature of the entrepreneurial activity, or if it is a precarious form of employment of last resort. The evidence confronts the neoclassical view of the micro-entrepreneur sector. It is argued that self-employment should be interpreted as functional to the capital accumulation process and not as a residual activity.JEL classification: J23, L25
Identification of arginine- and lysine-methylation in the proteome of Saccharomyces cerevisiae and its functional implications
Authors: Pang Chi Nam Ignatius , Gasteiger Elisabeth , Wilkins Marc R 
Published: February 2010

AbstractBackgroundThe methylation of eukaryotic proteins has been proposed to be widespread, but this has not been conclusively shown to date. In this study, we examined 36,854 previously generated peptide mass spectra from 2,607Saccharomyces cerevisiaeproteins for the presence of arginine and lysine methylation. This was done using the FindMod tool and 5 filters that took advantage of the high number of replicate analysis per protein and the presence of overlapping peptides.ResultsA total of 83 high-confidence lysine and arginine methylation sites were found in 66 proteins. Motif analysis revealed many methylated sites were associated with MK,RGG/RXG/RGX or WXXXRmotifs. Functionally, methylated proteins were significantly enriched for protein translation, ribosomal biogenesis and assembly and organellar organisation and were predominantly found in the cytoplasm and ribosome. Intriguingly, methylated proteins were seen to have significantly longer half-life than proteins for which no methylation was found. Some 43% of methylated lysine sites were predicted to be amenable to ubiquitination, suggesting methyl-lysine might block the action of ubiquitin ligase.ConclusionsThis study suggests protein methylation to be quite widespread, albeit associated with specific functions. Large-scale tandem mass spectroscopy analyses will help to further confirm the modifications reported here.
Efficacy of Lactic Acid Bacteria (LAB) supplement in management of constipation among nursing home residents
Authors: An Hyang Mi , Baek Eun Hye , Jang Seok , Lee Do Kyung , Kim Mi Jin , Kim Jung Rae , Lee Kang Oh , Park Jong Gi , Ha Nam Joo 
Published: February 2010

AbstractBackgroundConstipation is a significant problem in the elderly, specifically nursing home and/or extended-care facility residents are reported to suffer from constipation. Lactic acid bacteria (LAB) are beneficial probiotic organisms that contribute to improved nutrition, microbial balance, and immuno-enhancement of the intestinal tract, as well as diarrhea and constipation effect. The objective of this study was to investigate the efficacy of this LAB supplement in the management of nursing home residents.MethodsNineteen subjects (8M, 11F; mean age 77.1 ± 10.1) suffering with chronic constipation were assigned to receive LAB (3.0 × 1011CFU/g) twice (to be taken 30 minutes after breakfast and dinner) a day for 2 weeks in November 2008. Subjects draw up a questionnaire on defecation habits (frequency of defecation, amount and state of stool), and we collected fecal samples from the subjects both before entering and after ending the trial, to investigate LAB levels and inhibition of harmful enzyme activities. Results were tested with SAS and Student's t-test.ResultsAnalysis of questionnaire showed that there was an increase in the frequency of defecation and amount of stool excreted in defecation habit after LAB treatment, but there were no significant changes. And it also affects the intestinal environment, through significantly increase (p< 0.05) fecal LAB levels. In addition, tryptophanase and urease among harmful enzyme activities of intestinal microflora were significantly decreased (p< 0.05) after LAB treatment.ConclusionLAB, when added to the standard treatment regimen for nursing home residents with chronic constipation, increased defecation habit such as frequency of defecation, amount and state of stool. So, it may be used as functional probiotics to improve human health by helping to prevent constipation.
Helicobacter pylori-induced activation of β-catenin involves low density lipoprotein receptor-related protein 6 and Dishevelled
Authors: Gnad Thorsten , Feoktistova Maria , Leverkus Martin , Lendeckel Uwe , Naumann Michael 
Published: February 2010

AbstractBackgroundThe human microbial pathogenHelicobacter pyloriresides in the stomach of about fifty percent of the world's population and represents a risk factor for chronic gastritis, peptic ulcers and, in rare cases, gastric cancer. Alterations of the Wnt/β-catenin signaling pathway have been described in almost every human cancer disease, due to the regulation of target genes being involved in cell cycle control, differentiation, cell migration or stem cell control. Our study aimed to elucidate the role of proximal Wnt signaling components low density lipoprotein receptor-related protein 6 (LRP6) and Dishevelled (Dvl) in the activation of β-catenin early after infection of gastric epithelial cells withH. pylori.ResultsInfection of gastric epithelial NCI-N87 cells withH. pyloriinduces rapid phosphorylation of the Wnt/β-catenin pathway co-receptor LRP6 independent of the cytotoxin-associated gene A (CagA) or vacuolating cytotoxin A (VacA). However, bacteria lacking a functional type 4 secretion system (T4SS) failed to induce LRP6 phosphorylation. Further, we identified proteins of the Dvl family, namely Dvl2 and Dvl3, which are involved in LRP6 phosphorylation.H. pylori-induced nuclear accumulation of β-catenin and its transcriptional activation, and expression of Wnt target genes are strongly reduced in stable knockdown cell lines deficient for LRP6, Dvl2 or Dvl3.ConclusionWe analysed theH. pylori-induced activation of Wnt-signaling factors and demonstrate for the first time that the canonical Wnt-signaling proteins LRP6 and Dvl2 and Dvl3 are involved in the regulation of β-catenin.
Ceramide and ceramide 1-phosphate in health and disease
Authors: Arana Lide , Gangoiti Patricia , Ouro Alberto , Trueba Miguel , Gómez-Muñoz Antonio 
Published: February 2010

AbstractSphingolipids are essential components of cell membranes, and many of them regulate vital cell functions. In particular, ceramide plays crucial roles in cell signaling processes. Two major actions of ceramides are the promotion of cell cycle arrest and the induction of apoptosis. Phosphorylation of ceramide produces ceramide 1-phosphate (C1P), which has opposite effects to ceramide. C1P is mitogenic and has prosurvival properties. In addition, C1P is an important mediator of inflammatory responses, an action that takes place through stimulation of cytosolic phospholipase A2, and the subsequent release of arachidonic acid and prostaglandin formation. All of the former actions are thought to be mediated by intracellularly generated C1P. However, the recent observation that C1P stimulates macrophage chemotaxis implicates specific plasma membrane receptors that are coupled to Gi proteins. Hence, it can be concluded that C1P has dual actions in cells, as it can act as an intracellular second messenger to promote cell survival, or as an extracellular receptor agonist to stimulate cell migration.
Differential genome-wide gene expression profiling of bovine largest and second-largest follicles: identification of genes associated with growth of dominant follicles
Authors: Hayashi Ken-Go , Ushizawa Koichi , Hosoe Misa , Takahashi Toru 
Published: February 2010

Abstract

Background
Bovine follicular development is regulated by numerous molecular mechanisms and biological pathways. In this study, we tried to identify differentially expressed genes between largest (F1) and second-largest follicles (F2), and classify them by global gene expression profiling using a combination of microarray and quantitative real-time PCR (QPCR) analysis. The follicular status of F1 and F2 were further evaluated in terms of healthy and atretic conditions by investigating mRNA localization of identified genes.

Methods
Global gene expression profiles of F1 (10.7 +/- 0.7 mm) and F2 (7.8 +/- 0.2 mm) were analyzed by hierarchical cluster analysis and expression profiles of 16 representative genes were confirmed by QPCR analysis. In addition, localization of six identified transcripts was investigated in healthy and atretic follicles using in situ hybridization. The healthy or atretic condition of examined follicles was classified by progesterone and estradiol concentrations in follicular fluid.

Results
Hierarchical cluster analysis of microarray data classified the follicles into two clusters. Cluster A was composed of only F2 and was characterized by high expression of 31 genes including IGFBP5, whereas cluster B contained only F1 and predominantly expressed 45 genes including CYP19 and FSHR. QPCR analysis confirmed AMH, CYP19, FSHR, GPX3, PlGF, PLA2G1B, SCD and TRB2 were greater in F1 than F2, while CCL2, GADD45A, IGFBP5, PLAUR, SELP, SPP1, TIMP1 and TSP2 were greater in F2 than in F1. In situ hybridization showed that AMH and CYP19 were detected in granulosa cells (GC) of healthy as well as atretic follicles. PlGF was localized in GC and in the theca layer (TL) of healthy follicles. IGFBP5 was detected in both GC and TL of atretic follicles. GADD45A and TSP2 were localized in both GC and TL of atretic follicles, whereas healthy follicles expressed them only in GC.

Conclusion
We demonstrated that global gene expression profiling of F1 and F2 clearly reflected a difference in their follicular status. Expression of stage-specific genes in follicles may be closely associated with their growth or atresia. Several genes identified in this study will provide intriguing candidates for the determination of follicular growth.
A case report of pseudoprogression followed by complete remission after proton-beam irradiation for a low-grade glioma in a teenager: the value of dynamic contrast-enhanced MRI
Authors: Meyzer Candice , Dhermain Frédéric , Ducreux Denis , Habrand Jean-Louis , Varlet Pascale , Sainte-Rose Christian , Dufour Christelle , Grill Jacques 
Published: February 2010

Abstract
A fourteen years-old boy was treated post-operatively with proton therapy for a recurrent low-grade oligodendroglioma located in the tectal region. Six months after the end of irradiation (RT), a new enhancing lesion appeared within the radiation fields. To differentiate disease progression from radiation-induced changes, dynamic susceptibility contrast-enhanced (DSCE) MRI was used with a T2* sequence to study perfusion and permeability characteristics simultaneously. Typically, the lesion showed hypoperfusion and hyperpermeability compared to the controlateral normal brain. Without additional treatment but a short course of steroids, the image disappeared over a six months period allowing us to conclude for a pseudo-progression. The patient is alive in complete remission more than 2 years post-RT.
Estrogen Negative Feedback on Gonadotropin Secretion: Evidence for a Direct Pituitary Effect in Women
Authors: Shaw N. D. , Histed S. N. , Srouji S. S. , Yang J. , Lee H. , Hall J. E. 
Published: February 2010

Abstract
Context: Studies in humans and animals indicate that estrogen negative feedback occurs at the level of the hypothalamus, but it is unclear whether estrogen also exerts an inhibitory effect directly at the pituitary.
Objectives: The aim of the study was to determine whether estrogen has a direct negative feedback effect at the pituitary and whether this varies with aging.
Design and Setting: A GnRH antagonist and graded doses of GnRH were used to isolate pituitary responsiveness before and after estrogen administration in Clinical Research Center studies at an academic medical center.
Subjects: Subjects were healthy postmenopausal women aged 48–56 yr (n = 8) or 70–75 yr (n= 8).
Interventions: A suppressive dose of the NAL-GLU GnRH antagonist was administered, followed by graded doses of GnRH before and after 1 month of estrogen administration.
Results: LH and FSH responses to GnRH decreased after estrogen administration (P = 0.01 and P = 0.0001, respectively). The ratio of FSH to LH amplitudes decreased in response to estrogen (P = 0.04) indicating a greater sensitivity of FSH than LH to inhibition by estrogen. The inhibitory effect of estrogen on FSH was attenuated with aging (P = 0.02), but was maintained for LH (P = 0.4).
Conclusions: Studies that control for endogenous GnRH and estradiol demonstrate a direct pituitary site of estrogen negative feedback on LH and FSH responsiveness to GnRH in women. The effect of estrogen on FSH responsiveness is greater than on LH and is attenuated with aging. These studies indicate that estrogen negative feedback occurs directly at the pituitary and contributes to the differential regulation of FSH and LH secretion.
Sex Hormone-Binding Globulin as an Independent Determinant of Cortical Bone Status in Men at the Age of Peak Bone Mass
Authors: Vanbillemont Griet , Lapauw Bruno , Bogaert Veerle , Goemaere Stefan , Zmierczak Hans-Georg , Taes Youri , Kaufman Jean-Marc 
Published: February 2010

AbstractContext: Sex steroids are important determinants of the skeletal development, growth, and maintenance after achievement of peak bone mass. A large fraction of these hormones are bound by SHBG, and previous studies have shown that SHBG could be a determinant of bone characteristics.Objective: We investigated associations of serum SHBG levels with cortical and trabecular bone characteristics in young healthy men.Design and Settings: A total of 677 healthy male siblings aged 25–45 yr were recruited in a cross-sectional, population-based study.Main Outcomes: Areal bone parameters were assessed using dual-energy x-ray absorptiometry. Cortical bone parameters at the tibia and radius and trabecular vBMD at the radius were assessed using peripheral quantitative computed tomography. Serum testosterone, estradiol, and SHBG levels were measured using immunoassays.Results: Regression models including age, height, and weight showed that SHBG levels were positively associated with bone area at the hip and the whole body, but not with areal bone mineral density (BMD). Higher SHBG levels were associated with a larger cortical bone area and periosteal and endosteal circumferences at both the tibia and the radius, whereas trabecular volumetric BMD at the radius was negatively associated with SHBG levels. Associations persisted after adjustment for (free) sex steroid levels. No associations were found with cortical volumetric BMD or cortical thickness.Conclusion: In this population of healthy adult men at the age of peak bone mass, SHBG levels were positively associated with cortical bone size, independently from sex-steroid levels. This suggests a possible independent role of SHBG in the determination of adult bone size.
Analysis and modelling by finite element method of the equal channel angular extrusion pressure
Authors: Luri R , Luis Pérez C J 
Published: February 2010

Equal channel angular extrusion (ECAE) is a process used to impart severe plastic deformation within the material billet. This has a great deal of interest because of the improvement achieved in the mechanical properties of the material to be processed. In this study, a finite element method (FEM) analysis has been used in order to find out how the geometrical parameters of the ECAE dies and the part affect the punch force. This is important in order to predict the force required to perform the process accurately. By solving several finite element models with different geometries, a mathematical model for the extrusion pressure was obtained, and it has been possible to study the influence of the geometry on the processing force. From this, a better die design can be made. FEM modelling has been validated by comparison with experimental results. This comparison has shown a good agreement between both of them (a difference lower than 8 per cent). Moreover, the error obtained with an analytical analysis based on the upper bound method has been determined by comparison of analytical and FEM results. This has shown that the difference between analytical and FEM results was less than 9 per cent.
Suppression of Cell Adhesion on Well-defined Concentrated Polymer Brushes of Hydrophilic Polymers
Authors: Yoshikawa Chiaki , Hashimoto Yoshihide , Hattori Shinya , Honda Takako , Zhang Kun , Terada Dohiko , Kishida Akio , Tsujii Yoshinobu , Kobayashi Hisatoshi 
Published: February 2010

Abstract
The cell adhesion was investigated on polymer brushes of poly(2-hydroxyethyl methacrylate) (PHEMA), poly(2-hydroxyethyl acrylate) (PHEA), and poly[poly(ethylene glycol) methyl ether methacrylate] (PPEGMA) with different graft densities (in semidilute and concentrated regimes) and thicknesses. The concentrated polymer brushes (CPBs) of all the three, regardless of differences in chemical structure and hydrophilicity, almost completely suppressed the adhesion of L929 fibroblast cell in contrast to the corresponding semidilute polymer brushes (SDPBs). Along with our previous study on excellent protein repellency of CPB owing to its unique size-exclusion effect (of entropic origin), we concluded that such bioinertness should be commonly found in CPB of neutral and hydrophilic polymers.
Analyse des Übertragungsverhaltens von Differenzdrucksensoren durch dynamische DruckkalibrierungAnalyzing Frequency Response of Differential Pressure Sensors by Dynamic Pressure Calibration
Authors: Kober Timo , Sindlinger Stefan , Werthschützky Roland 
Published: February 2010

Zusammenfassung
Stand der Technik bei Differenzdrucksensoren für die Prozessmesstechnik ist ein Nennmessbereich von Δp
N=10 mbar bei einem statischen Nenndruck bis p
Stat=160 bar. Dabei wird eine Messunsicherheit ≤2×10-3 angestrebt. Drucksensoren für raue Umgebungsbedingungen, deren Verformungskörper aus Silizium besteht, benötigen metallische Trennmembranen zur Medientrennung. Zum Schutz des Meßelementes vor zu hoher statischer und dynamischer Druckbelastung werden spezielle mechanische Überlastschutzvorrichtungen verwendet. Um zuverlässige Überlastschutzsysteme zu entwickeln, wird deren Frequenzcharakteristik experimentell durch eine neuartige dynamische Druckquelle ermittelt.
Anregung und drahtlose Lock-in-Messung von Hüftprothesenschwingungen zur LockerungsdetektionExcitation and Wireless Lock-in Measurement of Hip Prosthesis Vibrations for Loosening Detection
Authors: Marschner Uwe , Jettkant Birger , Fischer Wolf-Joachim , Ruwisch Dietmar , Grätz Hagen , Woldt Gregor , Clasbrummel Bernhard 
Published: February 2010

Zusammenfassung
Es wird ein Experimentalaufbau zur Anregung und drahtlosen Messung von Schwingungen einer teilweise in einen künstlichen Oberschenkelknochen einzementierten Hüftprothese vorgestellt. Um das dynamische Verhalten des mechanischen Systems zu diskutieren, wurde ein translatorisch-rotatorisches Netzwerkmodell erstellt. Mit diesem Modell werden die Eigenfrequenzen des Femur-Prothesen-Verbundes berechnet.
Taktil-optischer 3D-Taster zur Messung von MikrobauteilenThree-Dimensional Tactile-Optical Probing for the Measurement of Microparts
Authors: Tutsch Rainer , Andräs Matthias , Neuschaefer-Rube Ulrich , Petz Marcus , Wiedenhöfer Thomas , Wissmann Mark 
Published: February 2010

Zusammenfassung
Die taktile Messung von Mikrobauteilen erfordert Taster mit sehr kleinen Antastelementen und Antastkräften. Der taktil-optische Taster (sog. Fasertaster) stellt hierbei eine herausragende, etablierte Lösung dar und erlaubt auch die Messung von ansonsten unzugänglichen Mikrogeometrien. Allerdings war durch die auf diesem Prinzip basierende taktil-optische Messmethode bislang keine volle 3D-Messfähigkeit erreichbar. Neue Ansätze zur Überwindung dieser Einschränkung stellen die stereoskopische Erfassung der Tastkugel sowie die auf einem Speckle-Muster basierende Auswertung der z-Auslenkung des Tastelements dar.