984 resultados para dynamic monitoring
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We study the minimum mean square error (MMSE) and the multiuser efficiency η of large dynamic multiple access communication systems in which optimal multiuser detection is performed at the receiver as the number and the identities of active users is allowed to change at each transmission time. The system dynamics are ruled by a Markov model describing the evolution of the channel occupancy and a large-system analysis is performed when the number of observations grow large. Starting on the equivalent scalar channel and the fixed-point equation tying multiuser efficiency and MMSE, we extend it to the case of a dynamic channel, and derive lower and upper bounds for the MMSE (and, thus, for η as well) holding true in the limit of large signal–to–noise ratios and increasingly large observation time T.
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Monitoring of posture allocations and activities enables accurate estimation of energy expenditure and may aid in obesity prevention and treatment. At present, accurate devices rely on multiple sensors distributed on the body and thus may be too obtrusive for everyday use. This paper presents a novel wearable sensor, which is capable of very accurate recognition of common postures and activities. The patterns of heel acceleration and plantar pressure uniquely characterize postures and typical activities while requiring minimal preprocessing and no feature extraction. The shoe sensor was tested in nine adults performing sitting and standing postures and while walking, running, stair ascent/descent and cycling. Support vector machines (SVMs) were used for classification. A fourfold validation of a six-class subject-independent group model showed 95.2% average accuracy of posture/activity classification on full sensor set and over 98% on optimized sensor set. Using a combination of acceleration/pressure also enabled a pronounced reduction of the sampling frequency (25 to 1 Hz) without significant loss of accuracy (98% versus 93%). Subjects had shoe sizes (US) M9.5-11 and W7-9 and body mass index from 18.1 to 39.4 kg/m2 and thus suggesting that the device can be used by individuals with varying anthropometric characteristics.
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SUMMARY : Detailed knowledge of the different components of the immune system is required for the development of new immunotherapeutic strategies. CD4 T lymphocytes represent a highly heterogeneous group of cells characterized by various profiles of cytokine production and effector vs. regulatory functions. They are central players in orchestrating adaptive immune responses: unbalances between the different subtypes can lead either to aggressive autoimmune disorders or can favour the uncontrolled growth of malignancies. In this study we focused on the characterization of human CD4 T cells in advanced stage melanoma patients as well as in patients affected by various forms of autoimmune inflammatory spondyloarthropathies. In melanoma patients we report that a population of FOXP3 CD4 T cells, known as regulatory T cells, is overrepresented in peripheral blood, and even more in tumor-infitrated lymph nodes as well as at tumor sites, as compared to healthy donors. In tumor-infiltrated lymph nodes, but not in normal lymph nodes or in peripheral blood, FOXP3 CD4 T cells feature a highly differentiated phenotype (CD45RA-CCR7+/-), which suggests for a recent encounter with their cognate antigen. FOXP3 CD4 T cells have been described to be an important component of the several known immune escape mechanisms. We demonstrated that FOXP3 CD4 T cells isolated from melanoma patients exert an in vitro suppressive action on autologous CD4 T cells, thus possibly inhibiting an efficient anti-tumor response. Next, we aimed to analyse CD4 T cells at antigen-specific level. In advanced stage melanoma patients, we identified for the first time, using pMHCII multimers, circulating CD4 T cells specific for the melanoma antigen Melan-A, presented by HLA-DQB1 *0602. Interestingly, in a cohort of melanoma patients enrolled in an immunotherapy trails consisting of injection of a Melan-A derived peptide, we did not observe signif cant variations in the ex vivo frequencies of Melan-A specific CD4 T cells, but important differences in the quality of the specific CD4 T cells. In fact, up to 50% of the ex vivo Melan-A/DQ6 specific CD4 T cells displayed a regulatory phenotype and were hypoproliferative before vaccination, while more effector, cytokine-secreting Melan-A/DQ6 specific CD4 T cells were observed after immunization. These observations suggest that peptide vaccination may favourably modify the balance between regulatory and effector tumor-specific CD4 T cells. Finally, we identified another subset of CD4 T cells as possible mediator of pathology in a group of human autoimmune spondyloarthropathies, namely Th17 cells. These cells were recently described to play a critical role in the pathogenesis of some marine models of autommunity. We document an elevated presence of circulating Th17 cells in two members of seronegative spondyloarthropathies, e.g. psoriatic arthritis and ankylosing spondylitis, while we do not observe increased frequencies of Th17 cells in peripheral blood of rheumatoid arthritic patients. In addition, Th17 cells with a more advanced differentiation state (CD45RA-CCR7-CD27-) and polyfunctionality (concomitant secretion of IL-17, IL-2 and TNFα) were observed exclusively in patients with seronegative spondylarthropathies. Together, our observations emphasize the importance of CD4 T cells in various diseases and suggest that immunotherapeutic approaches considering CD4 T cells as targets should be evaluated in the future.
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The shape of alliance processes over the course of psychotherapy has already been studied in several process-outcome studies on very brief psychotherapy. The present study applies the shape-of-change methodology to short-term dynamic psychotherapies and complements this method with hierarchical linear modeling. A total of 50 psychotherapies of up to 40 sessions were included. Alliance was measured at the end of each session. The results indicate that a linear progression model is most adequate. Three main patterns were found: stable, linear, and quadratic growth. The linear growth pattern, along with the slope parameter, was related to treatment outcome. This study sheds additional light on alliance process research, underscores the importance of linear alliance progression for outcome, and also fosters a better understanding of its limitations.
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Predicting which species will occur together in the future, and where, remains one of the greatest challenges in ecology, and requires a sound understanding of how the abiotic and biotic environments interact with dispersal processes and history across scales. Biotic interactions and their dynamics influence species' relationships to climate, and this also has important implications for predicting future distributions of species. It is already well accepted that biotic interactions shape species' spatial distributions at local spatial extents, but the role of these interactions beyond local extents (e.g. 10 km(2) to global extents) are usually dismissed as unimportant. In this review we consolidate evidence for how biotic interactions shape species distributions beyond local extents and review methods for integrating biotic interactions into species distribution modelling tools. Drawing upon evidence from contemporary and palaeoecological studies of individual species ranges, functional groups, and species richness patterns, we show that biotic interactions have clearly left their mark on species distributions and realised assemblages of species across all spatial extents. We demonstrate this with examples from within and across trophic groups. A range of species distribution modelling tools is available to quantify species environmental relationships and predict species occurrence, such as: (i) integrating pairwise dependencies, (ii) using integrative predictors, and (iii) hybridising species distribution models (SDMs) with dynamic models. These methods have typically only been applied to interacting pairs of species at a single time, require a priori ecological knowledge about which species interact, and due to data paucity must assume that biotic interactions are constant in space and time. To better inform the future development of these models across spatial scales, we call for accelerated collection of spatially and temporally explicit species data. Ideally, these data should be sampled to reflect variation in the underlying environment across large spatial extents, and at fine spatial resolution. Simplified ecosystems where there are relatively few interacting species and sometimes a wealth of existing ecosystem monitoring data (e.g. arctic, alpine or island habitats) offer settings where the development of modelling tools that account for biotic interactions may be less difficult than elsewhere.
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Postoperative neurosurgical patients are at risk of developing complications. Systemic and neuro-monitoring are used to identify patients who deteriorate in order to treat the underlying cause and minimize the impact on outcome. Hypotension and hypoxia are likely to be the most frequent insults and can be detected easily with blood pressure monitoring and pulse oximetry. Repeated clinical examination, however, is probably the most important monitor in the postoperative setting. Clinical scores such as the Glasgow Coma Score and the more recently introduced FOUR Score are important tools to standardize the clinical assessment. Intracranial pressure monitoring, cerebral blood flow monitoring, electroencephalography, and brain imaging are often used postoperatively. Despite the numerous publications on this topic only few studies address the impact of postoperative monitoring on outcome. Accordingly, in most patients the decision on which monitors are to be used must be based on the patient's presentation and clinical judgment.
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Therapeutic drug monitoring (TDM), combined in certain situations with pharmacogenetic tests of metabolism, has proven a valuable tool for psychopharmacotherapy. Uncertain drug adherence, suboptimal tolerability, nonresponse at therapeutic doses, or pharmacokinetic drug-drug interactions are typical situations when measurement of medication concentrations is helpful. This article is an adaptation of guidelines recently issued by the AGNP-TDM group (Hiemke et al., www. agnp.de), but its content focuses mainly on the TDM of antidepressants. Finally, the potential benefits of TDM for optimization of pharmacotherapy can only be obtained if the method is adequately integrated into the clinical treatment process.
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A l'heure actuelle, le monitoring de la problématique du cannabis en Suisse constitue un ensemble de travaux qui permettent le suivi de la situation au niveau national et qui sont mis en oeuvre par un consortium d'instituts. Ce monitoring comprend l'étude présentée dans ce rapport, l'étude sentinelle. Elle s'intéresse à l'évolution de la situation en matière de cannabis ainsi qu'à la gestion de cette situation au niveau local. Ainsi, les observations relevées par des professionnels de terrain dans différents domaines (santé/social, école/formation professionnelle, police/justice) et dans quatre cantons suisses (St Gall, Tessin, Vaud, Zurich), dits "sentinelle", sont récoltées et analysées annuellement. [P. 5]
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The Division of Criminal and Juvenile Justice Planning issued its first state legislation monitoring report in February 2002, covering the first six months’ impact of Senate File 543 (which enacted a number of sentencing changes) on the justice system; monitoring of the correctional impact of this bill was at the request of several members of the legislature. Since then, the Criminal and Juvenile Justice Planning Advisory Council has requested that CJJP monitor the correctional impact of enacted legislation of particular interest. This report covers monitoring results or future plans to monitor the following: 1. Changes in “crack” cocaine and “powder” cocaine penalties under Chapter 124.401 (effective FY2004; see p.3). 2. Commitments to prison involving manufacture, distribution, or possession of methamphetamine under Chapter 124.401 (see p.5). 3. Prosecution of offenders for child endangerment under Chapter 726.6(g) for permitting the presence of a child or minor at a location where a controlled substance manufacturing or a product possession violation occurs (see p.7). 4. Provision of an enhanced penalty for manufacturing of controlled substances under Chapter 124.401C when children are present and the offender is not charged under section 726.6(g) (see p. 7). 5. Creating a new offense when a retailer sells more than two packages of any product containing pseudoephedrine (chapter 126.23A) and providing for an enhanced penalty under Chapter 714.7C when a theft involves more than two packages of similar products (see p.8). 6. Establishment of parole eligibility at 70% of time served for persons sentenced under the “85% law” provisions of Iowa Code Section 902.12. (effective FY2005; see p. 9).
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Bone is a physiologically dynamic tissue being constantly regenerated throughout life as a consequence of bone turnover by bone-resorbing osteoclasts and bone-forming osteoblasts. In certain bone diseases, such as osteoporosis, the imbalance in bone turnover leads to bone loss and increased fracture risk. Measurement of bone mineral density (BMD) predicts the risk of fracture, but also biochemical markers of bone metabolism have been suggested to be suitable for prediction of fractures and monitoring the efficacy of antiresorptive treatment. Tartrate-resistant acid phosphatase 5b (TRACP 5b) is an enzyme released from osteoclasts into the circulation, from where it can be detected kinetically or immunologically. Conventional assays for serum total TRACP were spectrophotometric and suffered from interference by other acid phosphatases and non-osteoclastic TRACP 5a isoform. Our aim was to develop novel immunoassays for osteoclastic TRACP 5b. Serum TRACP 5b levels were elevated in individuals with high bone turnover, such as children, postmenopausal women, patients with osteoporosis, Paget’s disease and breast cancer patients with bone metastases. As expected, hormone replacement therapy (HRT) in postmenopausal women decreased the levels of serum TRACP 5b. Surprisingly, the highest TRACP 5b levels were observed in individuals with rare autosomal dominant osteopetrosis type II (ADO2), which is characterized by high BMD and fracture risk with simultaneously elevated levels of deficient osteoclasts. In ADO2 patients, elevated levels of serum TRACP 5b were associated with high fracture frequency. It is likely that serum TRACP 5b reflects the number of inactive osteoclasts in ADO2. Similar results supporting the hypothesis that TRACP 5b would reflect the number of osteoclasts instead of their activity were observed with cultured osteoclasts and in animal models. Novel TRACP 5b immunoassays may prove to be of value either as independent or combinatory tools with other bone metabolic markers and BMD measurements in clinical practice and bone research.
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This report is a well illustrated and practical Guide intended to aid engineers and engineering technicians in monitoring, maintaining, and protecting bridge waterways so as to mitigate or prevent scour from adversely affecting the structural performance of bridge abutments, piers, and approach road embankments. Described and illustrated here are the scour processes affecting the stability of these components of bridge waterways. Also described and illustrated are methods for monitoring waterways, and the various methods for repairing scour damage and protecting bridge waterways against scour. The Guide focuses on smaller bridges, especially those in Iowa. Scour processes at small bridges are complicated by the close proximity of abutments, piers, and waterway banks, such that scour processes interact in ways difficult to predict and for which reliable design relationships do not exist. Additionally, blockage by woody debris or by ice, along with changes in approach channel alignment, can have greater effects on pier and abutment scour for smaller bridges. These considerations tend to cause greater reliance on monitoring for smaller bridges. The Guide is intended to augment and support, as a source of information, existing procedures for monitoring bridge waterways. It also may prompt some adjustments of existing forms and reports used for bridge monitoring. In accord with increasing emphasis on effective management of public facilities like bridges, the Guide ventures to include an example report format for quantitative risk assessment applied to bridge waterways. Quantitative risk assessment is useful when many bridges have to be evaluated for scour risk and damage, and priorities need to be determined for repair and protection work. Such risk assessment aids comparison of bridges at risk. It is expected that bridge inspectors will implement the Guide as a concise, handy reference available back at the office. The Guide also likely may be implemented as an educational primer for new inspectors who have yet to become acquainted with waterway scour. Additionally, the Guide may be implemented as a part of process to check whether existing bridge-inspection forms or reports adequately encompass bridge-waterway scour.