901 resultados para aggregated multicast


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The fourth component of human complement (C4) exists in blood as two major forms or isotypes which differ in their biochemical and functional properties. Because C4A preferentially transacylates onto amino groups, it has been postulated that this isotype is more important in the clearance of immune complexes. Patients having systemic lupus erythematosus (SLE), an autoimmune disease, have an increased incidence of C4A null genes and presumably decreased levels of C4A. Currently accepted methods for the detection of C4, however, cannot accurately quantitate C4A and C4B. Thus, their role in disease susceptibility and activity has not been studied. A novel immunoassay, which utilized heat-aggregated IgG to activate and capture C4, was developed for accurate quantitation of total C4, C4A and C4B by monoclonal antibody conjugates. Higher mean total C4 values were found in a healthy Black control population when compared to White controls. This appeared to be due to an increase in C4B. In SLE patients, mean total C4 levels were significantly lower than controls regardless of disease activity. Serial patient studies showed that the ratio of C4A:C4B remained relatively constant. When the patient group was compared to controls based on C4 null gene status, the mean levels of C4A were identical while C4B was decreased in the patients. This suggests that the common HLA-B8, Dr3 C4A*Q0 gene deletion found in SLE patients may also adversely affect genetic control of the C4B genes. Furthermore, low levels of C4A cannot fully account for disease development in SLE patients having C4A null genes. ^

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Relatively little is known about the distribution and seasonal movement patterns of shortnose sturgeon Acipenser brevirostrum and Atlantic sturgeon Acipenser oxyrinchus oxyrinchus occupying rivers in the northern part of their range. During 2006 and 2007, 40 shortnose sturgeon (66-113.4 cm fork length [FL]) and 8 Atlantic sturgeon (76.2-166.2 cm FL) were captured in the Penobscot River, Maine, implanted with acoustic transmitters, and monitored using an array of acoustic receivers in the Penobscot River estuary and Penobscot Bay. Shortnose sturgeon were present year round in the estuary and overwintered from fall (mid-October) to spring (mid-April) in the upper estuary. In early spring, all individuals moved downstream to the middle estuary. Over the course of the summer, many individuals moved upstream to approximately 2 km of the downstream-most dam (46 river kilometers [rkm] from the Penobscot River mouth [rkm 0]) by August. Most aggregated into an overwintering site (rkm 36.5) in mid-to late fall. As many as 50% of the tagged shortnose sturgeon moved into and out of the Penobscot River system during 2007, and 83% were subsequently detected by an acoustic array in the Kennebec River, located 150 km from the Penobscot River estuary. Atlantic sturgeon moved into the estuary from the ocean in the summer and concentrated into a 1.5-km reach. All Atlantic sturgeon moved to the ocean by fall, and two of these were detected in the Kennebec River. Although these behaviors are common for Atlantic sturgeon, regular coastal migrations of shortnose sturgeon have not been documented previously in this region. These results have important implications for future dam removals as well as for rangewide and river-specific shortnose sturgeon management.

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Intra-session network coding has been shown to offer significant gains in terms of achievable throughput and delay in settings where one source multicasts data to several clients. In this paper, we consider a more general scenario where multiple sources transmit data to sets of clients over a wireline overlay network. We propose a novel framework for efficient rate allocation in networks where intermediate network nodes have the opportunity to combine packets from different sources using randomized network coding. We formulate the problem as the minimization of the average decoding delay in the client population and solve it with a gradient-based stochastic algorithm. Our optimized inter-session network coding solution is evaluated in different network topologies and is compared with basic intra-session network coding solutions. Our results show the benefits of proper coding decisions and effective rate allocation for lowering the decoding delay when the network is used by concurrent multicast sessions.

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Purpose – A growing body of literature points to the importance of public service motivation (PSM) for the performance of public organizations. The purpose of this paper is to assess the method predominantly used for studying this linkage by comparing the findings it yields without and with a correction suggested by Brewer (2006), which removes the common-method bias arising from employee-specific response tendencies. Design/methodology/approach – First, the authors conduct a systematic review of published empirical research on the effects of PSM on performance and show that all studies found have been conducted at the individual level. Performance indicators in all but three studies were obtained by surveying the same employees who were also asked about their PSM. Second, the authors conduct an empirical analysis. Using survey data from 240 organizational units within the Swiss federal government, the paper compares results from an individual-level analysis (comparable to existing research) to two analyses where the data are aggregated to the organizational level, one without and one with the correction for common-method bias suggested by Brewer (2006). Findings – Looking at the Attraction to Policy-Making dimension of PSM, there is an interesting contrast: While this variable is positively correlated with performance in both the individual-level analysis and the aggregated data analysis without the correction for common-method bias, it is not statistically associated with performance in the aggregated data analysis with the correction. Originality/value – The analysis is the first to assess the robustness of the performance-PSM linkage to a correction for common-method bias. The findings place the validity of at least one part of the individual-level linkage between PSM and performance into question.

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Objective: Processes occurring in the course of psychotherapy are characterized by the simple fact that they unfold in time and that the multiple factors engaged in change processes vary highly between individuals (idiographic phenomena). Previous research, however, has neglected the temporal perspective by its traditional focus on static phenomena, which were mainly assessed at the group level (nomothetic phenomena). To support a temporal approach, the authors introduce time-series panel analysis (TSPA), a statistical methodology explicitly focusing on the quantification of temporal, session-to-session aspects of change in psychotherapy. TSPA-models are initially built at the level of individuals and are subsequently aggregated at the group level, thus allowing the exploration of prototypical models. Method: TSPA is based on vector auto-regression (VAR), an extension of univariate auto-regression models to multivariate time-series data. The application of TSPA is demonstrated in a sample of 87 outpatient psychotherapy patients who were monitored by postsession questionnaires. Prototypical mechanisms of change were derived from the aggregation of individual multivariate models of psychotherapy process. In a 2nd step, the associations between mechanisms of change (TSPA) and pre- to postsymptom change were explored. Results: TSPA allowed a prototypical process pattern to be identified, where patient's alliance and self-efficacy were linked by a temporal feedback-loop. Furthermore, therapist's stability over time in both mastery and clarification interventions was positively associated with better outcomes. Conclusions: TSPA is a statistical tool that sheds new light on temporal mechanisms of change. Through this approach, clinicians may gain insight into prototypical patterns of change in psychotherapy.

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The Social Web offers increasingly simple ways to publish and disseminate personal or opinionated information, which can rapidly exhibit a disastrous influence on the online reputation of organizations. Based on social Web data, this study describes the building of an ontology based on fuzzy sets. At the end of a recurring harvesting of folksonomies by Web agents, the aggregated tags are purified, linked, and transformed to a so-called fuzzy grassroots ontology by means of a fuzzy clustering algorithm. This self-updating ontology is used for online reputation analysis, a crucial task of reputation management, with the goal to follow the online conversation going on around an organization to discover and monitor its reputation. In addition, an application of the Fuzzy Online Reputation Analysis (FORA) framework, lesson learned, and potential extensions are discussed in this article.

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BACKGROUND The nine equivalents of nursing manpower use score (NEMS) is used to evaluate critical care nursing workload and occasionally to define hospital reimbursements. Little is known about the caregivers' accuracy in scoring, about factors affecting this accuracy and how validity of scoring is assured. METHODS Accuracy in NEMS scoring of Swiss critical care nurses was assessed using case vignettes. An online survey was performed to assess training and quality control of NEMS scoring and to collect structural and organizational data of participating intensive care units (ICUs). Aggregated structural and procedural data of the Swiss ICU Minimal Data Set were used for matching. RESULTS Nursing staff from 64 (82%) of the 78 certified adult ICUs participated in this survey. Training and quality control of scoring shows large variability between ICUs. A total of 1378 nurses scored one out of 20 case vignettes: accuracy ranged from 63.7% (intravenous medications) to 99.1% (basic monitoring). Erroneous scoring (8.7% of all items) was more frequent than omitted scoring (3.2%). Mean NEMS per case was 28.0 ± 11.8 points (reference score: 25.7 ± 14.2 points). Mean bias was 2.8 points (95% confidence interval: 1.0-4.7); scores below 37.1 points were generally overestimated. Data from units with a greater nursing management staff showed a higher bias. CONCLUSION Overall, nurses assess the NEMS score within a clinically acceptable range. Lower scores are generally overestimated. Inaccurate assessment was associated with a greater size of the nursing management staff. Swiss head nurses consider themselves motivated to assure appropriate scoring and its validation.

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Seed production, seed dispersal, and seedling recruitment are integral to forest dynamics, especially in masting species. Often these are studied separately, yet scarcely ever for species with ballistic dispersal even though this mode of dispersal is common in legume trees of tropical African rain forests. Here, we studied two dominant main-canopy tree species, Microberlinia bisulcata and Tetraberlinia bifoliolata (Caesalpinioideae), in 25 ha of primary rain forest at Korup, Cameroon, during two successive masting events (2007/2010). In the vicinity of c. 100 and 130 trees of each species, 476/580 traps caught dispersed seeds and beneath their crowns c. 57,000 pod valves per species were inspected to estimate tree-level fecundity. Seed production of trees increased non-linearly and asymptotically with increasing stem diameters. It was unequal within the two species’ populations, and differed strongly between years to foster both spatial and temporal patchiness in seed rain. The M. bisulcata trees could begin seeding at 42–44 cm diameter: at a much larger size than could T. bifoliolata (25 cm). Nevertheless, per capita life-time reproductive capacity was c. five times greater in M. bisulcata than T. bifoliolata owing to former’s larger adult stature, lower mortality rate (despite a shorter life-time) and smaller seed mass. The two species displayed strong differences in their dispersal capabilities. Inverse modelling (IM) revealed that dispersal of M. bisulcata was best described by a lognormal kernel. Most seeds landed at 10–15 m from stems, with 1% of them going beyond 80 m (<100 m). The direct estimates of fecundity significantly improved the models fitted. The lognormal also described well the seedling recruitment distribution of this species in 121 ground plots. By contrast, the lower intensity of masting and more limited dispersal of the heavier-seeded T. bifoliolata prevented reliable IM. For this species, seed density as function of distance to traps suggested a maximum dispersal distance of 40–50 m, and a correspondingly more aggregated seedling recruitment pattern ensued than for M. bisulcata. From this integrated field study, we conclude that the reproductive traits of M. bisulcata give it a considerable advantage over T. bifoliolata by better dispersing more seeds per capita to reach more suitable establishment sites, and combined with other key traits they explain its local dominance in the forest. Understanding the linkages between size at onset of maturity, individual fecundity, and dispersal capability can better inform the life-history strategies, and hence management, of co-occurring tree species in tropical forests.

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AIMS Primary percutaneous coronary intervention (PPCI) is the preferred reperfusion therapy in ST-elevation myocardial infarction (STEMI). We conducted this study to evaluate the contemporary status on the use and type of reperfusion therapy in patients admitted with STEMI in the European Society of Cardiology (ESC) member countries. METHODS AND RESULTS A cross-sectional descriptive study based on aggregated country-level data on the use of reperfusion therapy in patients admitted with STEMI during 2010 or 2011. Thirty-seven ESC countries were able to provide data from existing national or regional registries. In countries where no such registries exist, data were based on best expert estimates. Data were collected on the use of STEMI reperfusion treatment and mortality, the numbers of cardiologists, and the availability of PPCI facilities in each country. Our survey provides a brief data summary of the degree of variation in reperfusion therapy across Europe. The number of PPCI procedures varied between countries, ranging from 23 to 884 per million inhabitants. Primary percutaneous coronary intervention and thrombolysis were the dominant reperfusion strategy in 33 and 4 countries, respectively. The mean population served by a single PPCI centre with a 24-h service 7 days a week ranged from 31 300 inhabitants per centre to 6 533 000 inhabitants per centre. Twenty-seven of the total 37 countries participated in a former survey from 2007, and major increases in PPCI utilization were observed in 13 of these countries. CONCLUSION Large variations in reperfusion treatment are still present across Europe. Countries in Eastern and Southern Europe reported that a substantial number of STEMI patients are not receiving any reperfusion therapy. Implementation of the best reperfusion therapy as recommended in the guidelines should be encouraged.

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The p62/SQSTM1 adapter protein has an important role in the regulation of several key signaling pathways and helps transport ubiquitinated proteins to the autophagosomes and proteasome for degradation. Here, we investigate the regulation and roles of p62/SQSTM1 during acute myeloid leukemia (AML) cell maturation into granulocytes. Levels of p62/SQSTM1 mRNA and protein were both significantly increased during all-trans retinoic acid (ATRA)-induced differentiation of AML cells through a mechanism that depends on NF-κB activation. We show that this response constitutes a survival mechanism that prolongs the life span of mature AML cells and mitigates the effects of accumulation of aggregated proteins that occurs during granulocytic differentiation. Interestingly, ATRA-induced p62/SQSTM1 upregulation was impaired in maturation-resistant AML cells but was reactivated when differentiation was restored in these cells. Primary blast cells of AML patients and CD34(+) progenitors exhibited significantly lower p62/SQSTM1 mRNA levels than did mature granulocytes from healthy donors. Our results demonstrate that p62/SQSTM1 expression is upregulated in mature compared with immature myeloid cells and reveal a pro-survival function of the NF-κB/SQSTM1 signaling axis during granulocytic differentiation of AML cells. These findings may help our understanding of neutrophil/granulocyte development and will guide the development of novel therapeutic strategies for refractory and relapsed AML patients with previous exposure to ATRA.

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AIMS HIV infection may be associated with an increased recurrence rate of myocardial infarction. Our aim was to determine whether HIV infection is a risk factor for worse outcomes in patients with coronaray artery disease. METHODS We compared data aggregated from two ongoing cohorts: (i) the Acute Myocardial Infarction in Switzerland (AMIS) registry, which includes patients with acute myocardial infarction (AMI), and (ii) the Swiss HIV Cohort Study (SHCS), a prospective registry of HIV-positive (HIV+) patients. We included all patients who survived an incident AMI occurring on or after 1st January 2005. Our primary outcome measure was all-cause mortality at one year; secondary outcomes included AMI recurrence and cardiovascular-related hospitalisations. Comparisons used Cox and logistic regression analyses, respectively. RESULTS There were 133 HIV+, (SHCS) and 5,328 HIV-negative [HIV-] (AMIS) individuals with incident AMI. In the SHCS and AMIS registries, patients were predominantly male (72% and 85% male, respectively), with a median age of 51 years (interquartile range [IQR] 46-57) and 64 years (IQR 55-74), respectively. Nearly all (90%) of HIV+ individuals were on successful antiretroviral therapy. During the first year of follow-up, 5 (3.6%) HIV+ and 135 (2.5%) HIV- individuals died. At one year, HIV+ status after adjustment for age, sex, calendar year of AMI, smoking status, hypertension and diabetes was associated with a higher risk of death (HR 4.42, 95% CI 1.73-11.27). There were no significant differences in recurrent AMIs (4 [3.0%] HIV+ and 146 [3.0%] HIV- individuals, OR 1.16, 95% CI 0.41-3.27) or in hospitalization rates (OR 0.68 [95% CI 0.42-1.11]). CONCLUSIONS HIV infection was associated with a significantly increased risk of all-cause mortality one year after incident AMI.

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OBJECTIVE Hypertension and an atherogenic lipid profile are known risk factors for coronary heart disease (CHD). Hypertensives show greater changes in atherogenic plasma lipids to acute stress than normotensives. In this study, we investigated whether attribution of failure is associated with lipid stress reactivity in hypertensive compared with normotensive men. METHODS 18 normotensive and 17 hypertensive men (mean±SEM; 45±2.2 years) underwent an acute standardized psychosocial stress task that can be viewed as a situation of experimentally induced failure. We assessed external-stable (ES), external-variable (EV), internal-stable (IS), and internal-variable (IV) attribution of failure and psychological control variables (i.e. extent of depression and neuroticism). Moreover, total cholesterol (TC), low-density-lipoprotein cholesterol (LDL-C), and norepinephrine were measured immediately before and several times after stress. RESULTS ES moderated TC- and LDL-C-stress reactivity in hypertensives as compared to normotensives (interaction mean arterial pressure [MAP]-by-ES for TC: F=3.71, p=.015; for LDL-C: F=3.61, p=.016). TC and LDL-C levels were highest in hypertensives with low ES immediately after stress (p≤.039). In contrast, hypertensives with high ES did not differ from normotensives in TC and LDL-C immediately after stress (p's>.28). Controlling for norepinephrine, depression, and neuroticism in addition to age and BMI did not significantly change results. There were no significant associations between lipid baseline levels or aggregated lipid secretion and IS, IV, or EV (p's>.23). CONCLUSION Our data suggest that ES may independently protect from elevated lipid stress reactivity in hypertensive individuals. ES thus might be a protective factor against CHD in hypertension.

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BACKGROUND Associations between social status and health behaviours are well documented, but the mechanisms involved are less understood. Cultural capital theory may contribute to a better understanding by expanding the scope of inequality indicators to include individuals' knowledge, skills, beliefs and material goods to examine how these indicators impact individuals' health lifestyles. We explore the structure and applicability of a set of cultural capital indicators in the empirical exploration of smoking behaviour among young male adults. METHODS We analysed data from the Swiss Federal Survey of Adolescents (CH-X) 2010-11 panel of young Swiss males (n = 10 736). A set of nine theoretically relevant variables (including incorporated, institutionalized and objectified cultural capital) were investigated using exploratory factor analysis. Regression models were run to observe the association between factor scores and smoking outcomes. Outcome measures consisted of daily smoking status and the number of cigarettes smoked by daily smokers. RESULTS Cultural capital indicators aggregated in a three-factor solution representing 'health values', 'education and knowledge' and 'family resources'. Each factor score predicted the smoking outcomes. In young males, scoring low on health values, education and knowledge and family resources was associated with a higher risk of being a daily smoker and of smoking more cigarettes daily. CONCLUSION Cultural capital measures that include, but go beyond, educational attainment can improve prediction models of smoking in young male adults. New measures of cultural capital may thus contribute to our understanding of the social status-based resources that individuals can use towards health behaviours.

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Amongst the various hypotheses that challenged to explain the coexistence of species with similar life histories, theoretical, and empirical studies suggest that spatial processes may slow down competitive exclusion and hence promote coexistence even in the absence of evident trade-offs and frequent disturbances. We investigated the effects of spatial pattern and density on the relative importance of intra- and interspecific competition in a field experiment. We hypothesized that weak competitors increased biomass and seed production within neighborhoods of conspecifics, while stronger competitors would show increased biomass and seed production within neighborhoods of heterospecifics. Seeds of four annual plant species (Capsella bursa-pastoris, Stachys annua, Stellaria media, Poa annua) were sown in two spatial patterns (aggregated vs. random) and at two densities (low vs. high) in three different species combinations (monocultures, three and four species mixtures). There was a hierarchy in biomass production among the four species and C. bursa-pastoris and S. media were among the weak competitors. Capsella and Stellaria showed increased biomass production and had more individuals in the aggregated compared to the random pattern, especially when both superior competitors (S. annua, P. annua) were present. For P. annua we observed considerable differences among species combinations and unexpected pattern effects. Our findings support the hypothesis that weak competitors increase their fitness when grown in the neighborhood of conspecifics, and suggested that for the weakest competitors the species identity is not important and all other species are best avoided through intraspecific aggregation. In addition, our data suggest that the importance of spatial pattern for the other competitors might not only depend on the position within the hierarchy but also on the identity of neighbor species, species characteristics, below ground interactions, and other nonspatial factors.

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Sport-motor tests play an important role in football talent selections. However, single tests represent only parts of the complex game performance. The best game performance therefore does not necessarily need to go hand in hand with the best results in all tests of a test battery. Considering the complexity of the game performance appropriately, a holistic perspective together with a person-oriented approach are applied. Thereby, systems consisting of several variables are identified and analysed in a longitudinal study. Following this idea, six sport-motor tests were aggregated into a subsystem. 106 young male elite football players were tested three times (2011, 2012, 2013; Mage, t2011=12.26, SD=0.29). One year later (2014) their performance level was enquired. Data were analysed using the LICUR method, a cluster analytical method. Four patterns were identified, which remained stable at all measuring points. The players frequently show intraindividual and structurally similar patterns over time. At the third measuring point, a pattern occurred out of which the players are significantly more likely to advance to the highest performance level one year later. This pattern appears consistently above average, but does not always show best test performances. The significantly frequent development along structurally stable patterns suggests a predictive validity of the subsystem sport-motor tests between the ages of 12 to 15. Above average, but not necessarily outstanding performances both in the motor abilities as well as in the football specific tests appears to be particularly promising. This finding emphasizes the need of a holistic perspective in the talent selection.