656 research outputs found
Confidentiality-Preserving Publish/Subscribe: A Survey
Publish/subscribe (pub/sub) is an attractive communication paradigm for
large-scale distributed applications running across multiple administrative
domains. Pub/sub allows event-based information dissemination based on
constraints on the nature of the data rather than on pre-established
communication channels. It is a natural fit for deployment in untrusted
environments such as public clouds linking applications across multiple sites.
However, pub/sub in untrusted environments lead to major confidentiality
concerns stemming from the content-centric nature of the communications. This
survey classifies and analyzes different approaches to confidentiality
preservation for pub/sub, from applications of trust and access control models
to novel encryption techniques. It provides an overview of the current
challenges posed by confidentiality concerns and points to future research
directions in this promising field
Le site du Lac Bleu et la question de l'extension du pergélisol en France au PléistocÚne supérieur
La revue des donnĂ©es issues de l'archĂ©ologie prĂ©ventive et programmĂ©e, des descriptions de coupes naturelles ou des photos aĂ©riennes conduit Ă recenser plusieurs centaines de structures pĂ©riglaciaires dans le Sud-Ouest de la France. Plusieurs catĂ©gories sont distinguĂ©es : 1) rĂ©seaux de polygones supradĂ©camĂ©triques correspondant Ă des coins Ă remplissage sableux primaire ou mixte, 2) coin Ă remplissage sableux primaire et, 3) rĂ©seau de petits polygones correspondant Ă des fentes de gel Ă maille semi-mĂ©triques Ă mĂ©triques. La datation OSL du remplissage de plusieurs coins sableux et l'information stratigraphique issue de sites prĂ©historiques montre que ces diffĂ©rentes structures traduisent plusieurs d'extension mĂ©ridionale du pergĂ©lisol plĂ©istocĂšne. L'interprĂ©tation de la signification palĂ©oclimatiques des structures, sans ĂȘtre univoque, conduit Ă distinguer des Ă©pisodes de pergĂ©lisol continu/discontinu et/ou sporadique. L'hypothĂšse d'une rĂ©currence de phases d'extension du PergĂ©lisol europĂ©en plĂ©istocĂšne en rĂ©ponse aux Ă©vĂ©nements de Heinrich entre 32ka et 17ka est avancĂ©e
First dating results for the Middle Pleistocene industries (Acheulean â Early Middle Palaeolithic) in the Pyrenees â Garonne region: a multi methods geochronological approach (TL, OSL and TT-OSL) of the Duclos and RomentĂšres sites
The recent development work of the A65 highway has given the opportunity to broaden the corpus of Lower and Middle Palaeolithic open-air sites known in the southern Aquitaine basin. The sites of Duclos (Auriac, Pyrénées-Orientales) and RomentÚres (Le Vignau, Landes), discovered in this context, have yielded an abundant lithic record which has been attributed to the Acheulean of Iberian type for the earlier and, essentially, to the Early Middle Palaeolithic for the latter. The archaeological levels are intercalated in sequences that comprise aeolian silts and colluvial units separated by interglacial luvisols. The pedostratigraphic context of the two sites has provided a rare opportunity to propose a reliable chronostratigraphic framework in this area. To achieve this objective, a study combining several methods of luminescence dating was conducted to complete the geomorphological data. Optically Stimulated Luminescence (OSL) and Thermically Transferred OSL (TT-OSL) dating methods were applied in order to determine the ages of sedimentary quartz grains and thus, of the sampled deposits. In parallel, heated flint and quartzite samples were dated by thermoluminescence (TL). The Pyrenees-Garonne Acheulean industry of Duclos has been attributed to the boundary between Marine Isotopic Stages (MIS) 7 and 6 while the human occupations of RomentÚres date from MIS 6 for the most recent series (Early Middle Palaeolithic) and from MIS 9 and 8 for the older
Arthroscopic Bristow-Latarjet Combined With Bankart Repair Restores Shoulder Stability in Patients With Glenoid Bone Loss
BACKGROUND: Arthroscopic Bankart repair alone cannot restore shoulder stability in patients with glenoid bone loss involving more than 20% of the glenoid surface. Coracoid transposition to prevent recurrent shoulder dislocation according to Bristow-Latarjet is an efficient but controversial procedure. QUESTIONS/PURPOSES: We determined whether an arthroscopic Bristow-Latarjet procedure with concomitant Bankart repair (1) restored shoulder stability in this selected subgroup of patients, (2) without decreasing mobility, and (3) allowed patients to return to sports at preinjury level. We also evaluated (4) bone block positioning, healing, and arthritis and (5) risk factors for nonunion and coracoid screw pullout. METHODS: Between July 2007 and August 2010, 79 patients with recurrent anterior instability and bone loss of more than 20% of the glenoid underwent arthroscopic Bristow-Latarjet-Bankart repair; nine patients (11%) were either lost before 2-year followup or had incomplete data, leaving 70 patients available at a mean of 35 months. Postoperative radiographs and CT scans were evaluated for bone block positioning, healing, and arthritis. Any postoperative dislocation or any subjective complaint of occasional to frequent subluxation was considered a failure. Physical examination included ROM in both shoulders to enable comparison and instability signs (apprehension and relocation tests). Rowe and Walch-Duplay scores were obtained at each review. Patients were asked whether they were able to return to sports at the same level and practice forced overhead sports. Potential risk factors for nonhealing were assessed. RESULTS: At latest followup, 69 of 70 (98%) patients had a stable shoulder, external rotation with arm at the side was 9° less than the nonoperated side, and 58 (83%) returned to sports at preinjury level. On latest radiographs, 64 (91%) had no osteoarthritis, and bone block positioning was accurate, with 63 (90%) being below the equator and 65 (93%) flush to the glenoid surface. The coracoid graft healed in 51 (73%), it failed to unite in 14 (20%), and graft osteolysis was seen in five (7%). Bone block nonunion/migration did not compromise shoulder stability but was associated with persistent apprehension and less return to sports. Use of screws that were too short or overangulated, smoking, and age higher than 35 years were risk factors for nonunion. CONCLUSIONS: The arthroscopic Bristow-Latarjet procedure combined with Bankart repair for anterior instability with severe glenoid bone loss restored shoulder stability, maintained ROM, allowed return to sports at preinjury level, and had a low likelihood of arthritis. Adequate healing of the transferred coracoid process to the glenoid neck is an important factor for avoiding persistent anterior apprehension. LEVEL OF EVIDENCE: Level IV, therapeutic study. See Instructions for Authors for a complete description of levels of evidence
The relationship between traits optimism and anxiety and health-related quality of life in patients hospitalized for chronic diseases: data from the SATISQOL study.
International audienceBACKGROUND: The impact of psychological factors is often taken into account in the evaluation of quality of life. However, the effect of optimism and trait anxiety remains controversial and they are rarely studied simultaneously. We aimed to study the effect of this factor on health-related quality of life (HRQOL) of patients after a hospitalization in relation with their chronic disease. METHODS: Using cross-sectional data from the SATISQOL cohort, we conducted a multicentric study, including patients hospitalized for an intervention in connection with their chronic disease. Six months after hospitalization, patients completed a generic HRQOL questionnaire (SF-36), and the STAI and LOT-R questionnaires to evaluate optimism and trait anxiety. We studied the effect of each trait on HRQOL separately, and simultaneously, taking account of their interaction in 3 models, using an ANOVA. RESULTS: In this study, 1529 patients were included in three participating hospitals and there existed wide diversity in the chronic diseases in our population. The HRQOL score increased for all dimensions of SF36 between 15,8 and 44,5 when the level of anxiety decreased (pâ<â0.0001) for the model 1, assessing the effect of anxiety on HRQOL and increased for all dimensions of SF36 between 3.1 and 12.7 with increasing level of optimism (<â0.0001) in the model 2 assessing the effect of optimism on HRQOL. In the model 3, assessing the effect of both anxiety and optimism on HRQOL, and their interaction, the HRQOL score for all dimensions of the SF36 increased when the level of anxiety decreased (pâ<â0.0001). It increased with increasing level of optimism (pâ<â0.006) in the model for all dimensions of SF36 except the Role Physical dimension. In this model, interaction between anxiety and optimism was significant for the Social Functioning dimension (pâ=â0.0021). CONCLUSIONS: Optimism and trait anxiety appeared to be significantly correlated with HRQOL. Furthermore, an interaction existed between the trait anxiety and optimism for some dimensions of SF36. Contrary to optimism, it seems essential to evaluate trait anxiety in future studies about HRQOL, since it could represent a confounding factor
Horizontal Gene Transfer Regulation in Bacteria as a âSpandrelâ of DNA Repair Mechanisms
Horizontal gene transfer (HGT) is recognized as the major force for bacterial genome evolution. Yet, numerous questions remain about the transferred genes, their function, quantity and frequency. The extent to which genetic transformation by exogenous DNA has occurred over evolutionary time was initially addressed by an in silico approach using the complete genome sequence of the Ralstonia solanacearum GMI1000 strain. Methods based on phylogenetic reconstruction of prokaryote homologous genes families detected 151 genes (13.3%) of foreign origin in the R. solanacearum genome and tentatively identified their bacterial origin. These putative transfers were analyzed in comparison to experimental transformation tests involving 18 different genomic DNA positions in the genome as sites for homologous or homeologous recombination. Significant transformation frequency differences were observed among these positions tested regardless of the overall genomic divergence of the R. solanacearum strains tested as recipients. The genomic positions containing the putative exogenous DNA were not systematically transformed at the highest frequencies. The two genomic âhot spotsâ, which contain recA and mutS genes, exhibited transformation frequencies from 2 to more than 4 orders of magnitude higher than positions associated with other genes depending on the recipient strain. These results support the notion that the bacterial cell is equipped with active mechanisms to modulate acquisition of new DNA in different genomic positions. Bio-informatics study correlated recombination âhot-spotsâ to the presence of Chi-like signature sequences with which recombination might be preferentially initiated. The fundamental role of HGT is certainly not limited to the critical impact that the very rare foreign genes acquired mainly by chance can have on the bacterial adaptation potential. The frequency to which HGT with homologous and homeologous DNA happens in the environment might have led the bacteria to hijack DNA repair mechanisms in order to generate genetic diversity without losing too much genomic stability
Disruption of the autoinhibited state primes the E3 ligase parkin for activation and catalysis
The PARK2 gene is mutated in 50% of autosomal recessive juvenile parkinsonism (ARJP) cases. It encodes parkin, an E3 ubiquitin ligase of the RBR family. Parkin exists in an autoinhibited state that is activated by phosphorylation of its Nâterminal ubiquitinâlike (Ubl) domain and binding of phosphoubiquitin. We describe the 1.8 Ă
crystal structure of human parkin in its fully inhibited state and identify the key interfaces to maintain parkin inhibition. We identify the phosphoubiquitinâbinding interface, provide a model for the phosphoubiquitinâparkin complex and show how phosphorylation of the Ubl domain primes parkin for optimal phosphoubiquitin binding. Furthermore, we demonstrate that the addition of phosphoubiquitin leads to displacement of the Ubl domain through loss of structure, unveiling a ubiquitinâbinding site used by the E2~Ub conjugate, thus leading to active parkin. We find the role of the Ubl domain is to prevent parkin activity in the absence of the phosphorylation signals, and propose a model for parkin inhibition, optimization for phosphoubiquitin recruitment, release of inhibition by the Ubl domain and engagement with an E2~Ub conjugate. Taken together, this model provides a mechanistic framework for activating parkin
1H-NMR urinary metabolomic profiling for diagnosis of gastric cancer
Background: Metabolomics has shown promise in gastric cancer (GC) detection. This research sought to identify whether GC has a unique urinary metabolomic profile compared with benign gastric disease (BN) and healthy (HE) patients. Methods: Urine from 43 GC, 40 BN, and 40 matched HE patients was analysed using 1H nuclear magnetic resonance (1H-NMR) spectroscopy, generating 77 reproducible metabolites (QC-RSD Results: GC displayed a clear discriminatory biomarker profile; the BN profile overlapped with GC and HE. LASSO-LR identified three discriminatory metabolites: 2-hydroxyisobutyrate, 3-indoxylsulfate, and alanine, which produced a discriminatory model with an area under the ROC of 0.95. Conclusions: GC patients have a distinct urinary metabolite profile. This study shows clinical potential for metabolic profiling for early GC diagnosis
2013 Doctoral Workshop on Distributed Systems
The Doctoral Workshop on Distributed Systems was held at Les Plans-sur-Bex, Switzerland, from June 26-28, 2013. Ph.D. students from the Universities of NeuchĂątel and Bern as well as the University of Applied Sciences of Fribourg presented their current research work and discussed recent research results. This technical report includes the extended abstracts of the talks given during the workshop
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