668 research outputs found

    Rician MIMO Channel- and Jamming-Aware Decision Fusion

    Full text link
    In this manuscript we study channel-aware decision fusion (DF) in a wireless sensor network (WSN) where: (i) the sensors transmit their decisions simultaneously for spectral efficiency purposes and the DF center (DFC) is equipped with multiple antennas; (ii) each sensor-DFC channel is described via a Rician model. As opposed to the existing literature, in order to account for stringent energy constraints in the WSN, only statistical channel information is assumed for the non-line-of sight (scattered) fading terms. For such a scenario, sub-optimal fusion rules are developed in order to deal with the exponential complexity of the likelihood ratio test (LRT) and impractical (complete) system knowledge. Furthermore, the considered model is extended to the case of (partially unknown) jamming-originated interference. Then the obtained fusion rules are modified with the use of composite hypothesis testing framework and generalized LRT. Coincidence and statistical equivalence among them are also investigated under some relevant simplified scenarios. Numerical results compare the proposed rules and highlight their jammingsuppression capability.Comment: Accepted in IEEE Transactions on Signal Processing 201

    Model Order Selection Rules For Covariance Structure Classification

    Full text link
    The adaptive classification of the interference covariance matrix structure for radar signal processing applications is addressed in this paper. This represents a key issue because many detection architectures are synthesized assuming a specific covariance structure which may not necessarily coincide with the actual one due to the joint action of the system and environment uncertainties. The considered classification problem is cast in terms of a multiple hypotheses test with some nested alternatives and the theory of Model Order Selection (MOS) is exploited to devise suitable decision rules. Several MOS techniques, such as the Akaike, Takeuchi, and Bayesian information criteria are adopted and the corresponding merits and drawbacks are discussed. At the analysis stage, illustrating examples for the probability of correct model selection are presented showing the effectiveness of the proposed rules

    asociacion entre angioma cavernoso y glioma cerebral reporte de dos casos y revision de la literatura acerca de los llamados angiogliomas

    Get PDF
    La asociacion entre las malformaciones vasculares y los gliomas cerebrales es inusual. Mientras que la asociacion entre angioma cavernoso con lesiones gliomatosas es aun mas rara, es por esto considerado por algunos autores como una entidad patologica particular llamada angioglioma. Los autores reportan dos casos de asociacion de un angioma cavernoso con una ganglioglioma y un oligodendroglioma, respectivamente. Ademas se realizo una revision de la literatura sobre los llamados angiogliomas. En opinion de los autores, la entidad de los angiogliomas se presenta dentro de un espectro general de neoplasias angiomatosas, que incluyen tumores cerebrales, en su mayoria gliomas de bajo grado, asociados a su vez, con un componente vascular importante

    The Effect of the Association between Donepezil and Choline Alphoscerate on Behavioral Disturbances in Alzheimer's Disease: Interim Results of the ASCOMALVA Trial

    Get PDF
    BACKGROUND: Behavioral and psychological symptoms of dementia (BPSD) are a group of psychological reactions, psychiatric symptoms, and behaviors commonly found in Alzheimer's disease (AD). Four clusters of BPSD have been described: mood disorders (depression, anxiety, and apathy), psychotic symptoms (delusions and hallucinations), aberrant motor behaviors (pacing, wandering, and other purposeless behaviors), and inappropriate behaviors (agitation, disinhibition, and euphoria). Most of them are attributed to acetylcholine deficiency. OBJECTIVE: To evaluate if a higher amount of acetylcholine obtained by associating donepezil and choline alphoscerate might have a favorable effect on BPSD. METHODS: BPSD were measured at baseline and after 24 months in 113 mild/moderate AD patients, included in the double-blind randomized trial ASCOMALVA, by the Neuropsychiatric Inventory (NPI). Two matched groups were compared: group A treated with donepezil (10 mg/day) plus choline alphoscerate (1200 mg/day), and group B treated with donepezil (10 mg/day) plus placebo. RESULTS: Data of NPI revealed a significant decrease of BPSD severity and distress of the caregiver in patients of group A compared with group B. Mood disorders (depression, anxiety and apathy) were significantly decreased in subjects treated with donepezil and choline alphoscerate, while their severity and frequency was increased in the other group. CONCLUSIONS: Patients treated with donepezil plus choline alphoscerate showed a lower level of behavioral disturbances than subjects treated with donepezil only, suggesting that the association can have beneficial effect

    Sleep Macrostructure and NREM Sleep Instability Analysis in Pediatric Developmental Coordination Disorder

    Get PDF
    Developmental Coordination Disorder (DCD) is considered to be abnormal motor skills learning, identified by clumsiness, slowness, and/or motor inaccuracy impairing the daily-life activities in all ages of life, in the absence of sensory, cognitive, or neurological deficits impairment. The present research focuses on studying DCD sleep structure and Cyclic Alternating Pattern (CAP) parameters with a full overnight polysomnography and to study the putative correlations between sleep architecture and CAP parameters with motor coordination skills. The study was a cross-sectional design involving 42 children (26M/16F; mean age 10.12 ± 1.98) selected as a DCD group compared with 79 children (49M/30F; mean age 9.94 ± 2.84) identified as typical (no-DCD) for motor ability and sleep macrostructural parameters according to the MABC-2 and polysomnographic (PSG) evaluations. The two groups (DCD and non-DCD) were similar for age (p = 0.715) and gender (p = 0.854). More significant differences in sleep architecture and CAP parameters were found between two groups and significant correlations were identified between sleep parameters and motor coordination skills in the study population. In conclusion, our data show relevant abnormalities in sleep structure of DCD children and suggest a role for rapid components of A phases on motor coordination development

    Influences of dietary supplementation with Lepidium meyenii (Maca) on stallion sperm production and on preservation of sperm quality during storage at 5 °C.

    Get PDF
    Stallion semen is damaged by oxidative stress during cooling and transport. Semen processing and extenders have been tested to improve the fertilizing capacity of semen and to preserve semen during transport. Dietary supplementation with natural antioxidants has been proposed to prevent oxidative damages. In this study, for the first time, the effect of dietary supplementation with Lepidium meyenii (Maca) on the characteristics of fresh and chilled stallion semen was evaluated. Maca is a traditional Andean crop used as a nutraceutical for the fertility-enhancing properties that are linked with antioxidant activity. The diet of five stallions was supplemented with 20 g of Maca powder daily for a total of 60 days. A control group of five stallions received the same diet without Maca. Semen was collected once before the administration of Maca (D0), twice during the administration at 30 and 60 days (D30 and D60), and finally twice at 30 and 60 days after the end of the administration (D90 and D120). Ejaculates were processed for cooled shipping at 5 °C and evaluated in the laboratory for total and progressive motility, acrosome integrity, and lipid peroxidation after collection and after 24, 48, and 72 h of storage. Dietary supplementation with Maca improved sperm concentration (from 213 ± 80.4 to 447 ± 73.1 × 106 spz/mL) and total sperm count (from 10,880 ± 4377 to 24,783 ± 4419 × 106 spz). The beneficial effects of Maca supplementation on motility and acrosome integrity in the raw semen were detected from the end of treatment with Maca (D60) until the end of the study (D120). Furthermore, during cooling storage, total motility, progressive motility, and acrosome integrity declined more slowly in the Maca-treated group than in the control group. Lipid peroxidation did not change during cooling storage in either group and did not show a significant difference between the two groups. In this study, the dietary supplementation with Maca increased sperm production and stabilized semen quality during chilled storage

    FEM analysis of RF breast ablation: Multiprobe versus cool-tip electrode

    Get PDF
    Background: Radio-frequency ablation (RFA) has recently received much attention as an effective minimally invasive strategy for the local treatment of tumors. The purpose of this study was to evaluate the efficacy of single-needle cool-tip RF breast ablation in terms of temperature distribution and duration of the procedure as compared to multiprobe RF breast ablation. Materials and Methods: Two different commercially available radiofrequency ablation needle electrodes were compared. Finite-element method (FEM) models were developed to simulate the thermoablation procedures. A series of ex vivo radiofrequency thermal lesions were induced to check the response of the FEM calculations. Results: Data obtained from FEM models and from ex vivo procedures showed that cool-tip RF breast ablation assures better performances than multiprobe RF breast ablation in terms of temperature distribution and duration of the procedure. Histopathological analysis of the cool-tip RF thermoablated specimens showed successful induction of coagulation necrosis in the thermoablated specimens. Conclusion: Data obtained from FEM models and from ex vivo procedures suggest that the proposed cool-tip RF breast ablation may kill more tumor cells in vivo with a single application than the multiprobe RF breast ablation

    Single-Center 8-Years Clinical Follow-Up of Cladribine-Treated Patients From Phase 2 and 3 Trials

    Get PDF
    Background: Cladribine is approved for the treatment of highly-active relapsing multiple sclerosis (MS), where it is also effective on disability progression. In the present single-center study, we aim to report on the 8-years clinical follow-up of 27 patients included in phase 2 and 3 clinical trials for cladribine. Methods: We included patients exposed to cladribine (n = 13) or placebo (n = 14) in ONWARD, CLARITY, and ORACLE-MS trials, and followed-up at the same center after trial termination. Outcomes of long-term disease progression were recorded. Results: During 8-year follow-up, patients treated with cladribine presented with reduced risk of EDSS progression (HR = 0.148; 95%CI = 0.031, 0.709; p = 0.017), of reaching EDSS 6.0 (HR = 0.115; 95%CI = 0.015, 0.872; p = 0.036), and of SP conversion (HR = 0.010; 95%CI = 0.001, 0.329; p = 0.010), when compared with placebo. Conclusions: Our exploratory study provides additional evidence that cladribine may be useful to prevent or, at least, mitigate the risk of disability progression after 8 years

    Cardiovascular profile improvement during Natalizumab treatment

    Get PDF
    Cardiovascular comorbidities are associated with the risk of MS progression. Thus, we aim to measure variations of cardiovascular risk factors during Natalizumab treatment and their possible clinical associations. Seventy-one relapsing-remitting MS patients treated with Natalizumab were followed-up during a 12.9 ± 6.2 months. Cardiovascular risk factors were recorded on first and last study visits: systolic blood pressure, uric acid, total cholesterol, LDL, HDL, and triglycerides. EDSS progression and relapse occurrence were recorded. At multilevel mixed-effects linear regression models, the population presented with a significant reduction of total cholesterol (Coeff = -7.340; 95%CI = -13.152--1.527; p = 0.013), and of HDL cholesterol (Coeff = -3.473; 95%CI = -6.333--0.613; p = 0.017), and a non-significant reduction of LDL cholesterol (Coeff = -1.872; 95%CI = -8.481-0.736; p = 0.053), and of triglycerides (Coeff = -8.815; 95%CI = -34.011-5.380; p = 0.094). Uric acid levels increased during the study period (Coeff = 0.159; 95%CI = 0.212-0.340; p = 0.038). No significant associations were found with clinical outcomes. Serum lipids decreased and anti-oxidant uric acid increased during Natalizumab treatment. These biomarkers need to be further explored in relation to clinical outcomes on larger cohorts with longer follow-ups
    • …
    corecore