3,336 research outputs found
Depart and approach procedures for UAS in a VFR environment
This paper assesses the depart and approach operations of Unmanned Aircraft Systems (UAS) in one of the most challenging scenarios: when flying under Visual Flight Rules (VFR). Inspired by some existing procedures for (manned) general aviation, some automatic and predefined procedures for UAS are proposed. Hence, standardized paths to specific waypoints close to the airport are defined for depart operations, just before starting the navigation phase. Conversely, and for the approach maneuvers, it is foreseen a first integration into a holding pattern near the landing runway (ideally above it) followed by a standard VFR airfield traffic pattern. This paper discusses the advantages of these operations which aim at minimizing possible conflicts with other existing aircraft while reducing the Pilot-in-Command workload. Finally, some preliminary simulations are shown where these procedures have been successfully tested with simulated surrounding traffic
Products of N-connected groups
[EN] Two subgroups H and K of a finite group G are said to be
N -connected if the subgroup generated by x and y is a nilpotent group,
for every pair of elements x in H and y in K. This paper is devoted to
the study of pairwise N -connected and permutable products of finitely
many groups, in the framework of formation and Fitting class theory.The second and third authors have been supported by Proyecto BMF2001-1667-C03-03, Ministerio de Ciencia y Tecnolog´ıa and FEDER, SpainHauck, P.; MartÃnez Pastor, A.; Perez Ramos, MD. (2003). Products of N-connected groups. Illinois Journal of Mathematics. 47(4):1033-1045. http://hdl.handle.net/10251/51893S1033104547
Analysis of Li-ion battery degradation using self-organizing maps
This paper proposes a new methodology to identify the different degradation processes of Li-Ion battery cells. The goal of this study is to determine if different degradation factors can be separated by waveform analysis from aged cells with similar remaining capacity. In contrast to other works, the proposed method identifies the past operating conditions in the cell, regardless of the actual State of Health. The methodology is based on a data-driven approach by using a SOM (Self-organizing map), an unsupervised neural network. To verify the hypothesis a SOM has been trained with laboratory data from whole data cycles, to classify cells concerning their degradation path and according to their discharge voltage patterns. Additionally, this new methodology based on the SOM allows discriminating groups of cells with different cycling conditions (based on depth of discharge, ambient temperature and discharge current). This research line is very promising for classification of used cells, not only depending on their current static parameters (capacity, impedance), but also the battery use in their past life. This will allow making predictions of the Remaining Useful Life (RUL) of a battery with greater precision
Beneficial effects of non-alcoholic grape-derived products on human health: a literature review
Vine is widely cultivated due to the economic value of wine and other grape derivatives.
The grape berry is characterized by the presence of a wide variety of flavonoids, which have been
investigated for their health promoting properties. Several epidemiological studies have shown that a
moderate consumption of wine is associated with a J-shaped effect on some risk factors for chronic
diseases. On the other hand, the wine market has shown a decreasing trend due to the frequent abuse
of alcoholic beverages also by young people, as denounced by WHO. Accordingly, the scientific
research in the field of non-alcoholic grape products has been further stimulated. The aim of this paper
was a preliminary collection of data on human studies supporting the beneficial properties of
unfermented grape products. The most convincing positive effects, observed in humans, consisted in
the reduction of risk factors for cardiovascular diseases, such as hypertension and oxidative stress.
Other human trials have been published in the area of: immune system, diabetes, cognitive functions,
oral health, and cancer. Generally speaking, the findings listed in this review support the use of nonalcoholic
grape derivatives, as a source of beneficial compounds for the human diet, even though
further studies are necessar
Raisins in human health : a review
In the last years, the scientific research in the field of non-alcoholic grape products has increased significantly. Raisins are often evaluated negatively from the nutritional point of view, mainly for their high sugar content. On the other hand, some in vitro and in vivo studies have suggested that raisins could have healthy effects due to their positive phytochemical profile. The aim of this work was the collection of scientific studies performed in humans to assess critically the health-promoting effects of raisins, as a part of the normal/Mediterranean diet. In most cases, the beneficial effects of raisins have been assessed in intervention studies focused on cardiovascular area, diabetes and oral health, where a decrease in postprandial glycemia and insulinemia both in diabetic and healthy subjects has been observed. The positive effects were generally evident after a short-term consumption of about 70 g/die of raisins in comparison to a similar quantity of snacks or glucose solution. Surprisingly, some positive findings were shown in oral health. On these bases several findings support the suitability of raisins as a source of healthy compounds for human diet, but limits in the data published till now clearly support the need of new specifically designed trials
Selenium and impaired physical function in US and Spanish older adults
Background: Selenium (Se) is a trace element with a narrow safety margin.
Objectives: To evaluate the cross-sectional and longitudinal dose-response association between Se exposure and
measures of impaired physical function and disability in older adults.
Design: NHANES 2011–2014 cross-sectional (US, n = 1733, age ≥60 years) and Seniors-ENRICA-2 2017–2019
cross-sectional and longitudinal (Spain, n = 2548 and 1741, respectively, age ≥65 years) data were analyzed.
Whole blood and serum Se levels were measured using inductively coupled plasma-mass spectrometry. Lowerextremity
performance was assessed with the Short Physical Performance Battery, and muscle weakness with
a dynamometer. Incident mobility and agility limitations, and disability in instrumental activities of daily living
(IADL) were ascertained with standardized questionnaires. Analyses were adjusted for relevant confounders,
including physical activity. Results across studies were pooled using random-effects meta-analysis.
Results: Meta-analyzed odds ratios (95% confidence interval) per log2 increase in whole blood Se were 0.54
(0.32; 0.76) for weakness, 0.59 (0.34; 0.83) for impaired lower-extremity performance, 0.48 (0.31; 0.68) for
mobility limitations, 0.71 (0.45; 0.97) for agility limitations, and 0.34 (0.12; 0.56) for disability in at least one
IADL. Analyses for serum Se in NHANES showed similar results. Findings suggest the inverse association with
grip strength is progressive below 140 μg/L (p-value for non-linear trend in the Seniors-ENRICA-2 study = 0.13),
and above 140 μg/L (p-value for non-linear trend in NHANES = 0.11). In the Seniors-ENRICA-2 cohort, with a
2.2 year follow-up period, a doubling in baseline Se levels were associated with a lower incidence of weakness
[odds ratio (95% confidence interval): 0.45 (0.22; 0.91)], impaired lower-extremity performance [0.63 (0.32;
1.23)], mobility [0.43 (0.21; 0.91)] and agility [0.38 (0.18; 0.78)] limitations.
Discussion: In US and Spanish older adults, Se concentrations were inversely associated with physical function
limitations. Further studies are needed to elucidate underlying mechanisms.Instituto de Salud Carlos III
European Commission
PI18/287
16/609State Secretary of R + D + I
PID2019-108973RB-C21/C22European Social Fund (ESF)
European Commissio
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Genetic susceptibility to telomere shortening through the rs2293607 polymorphism is associated with a greater risk of alcohol use disorder
Telomere shortening is usually considered a biomarker of ageing. Harmful alcohol use promotes accelerated biological ageing and alcohol use disorders (AUDs) are associated with short telomere length (TL). This study was conducted to examine the relationship of TL to AUD and determine whether single nucleotide polymorphisms (SNPs) in TERC and TERT modulate this association. For this purpose, we genotyped TERC SNPs rs2293607, rs12696304, and rs16847897 and TERT SNPs rs2735940, rs2736100, and rs2736098 in 308 male patients with AUD and 255 sex-matched healthy controls and measured TL in a subset of 99 patients and 99 controls paired by age and smoking status. Our results showed that the mean TL was shorter in patients with AUD than in controls. The area under the ROC curve was 0.70 (P < 0.001). The GG genotype of TERC rs2293607 was more common among patients with AUD than among controls (9.8% vs. 5.1%; P = 0.038). No difference was found for the other SNPs. Carriers of the GG genotype of rs2293607 had shorter telomeres than did allele A carriers. In conclusion, patients with AUD had shorter telomeres. Genetic susceptibility to telomere shortening through the rs2293607 SNP is associated with a greater risk of AUD
Sex differences between women and men with COPD: A new analysis of the 3CIA study
Background: There is partial evidence that COPD is expressed differently in women than in men, namely on symptoms, pulmonary function, exacerbations, comorbidities or prognosis. There is a need to improve the characterization of COPD in females.
Methods: We obtained and pooled data of 17 139 patients from 22 COPD cohorts and analysed the clinical differences by sex, establishing the relationship between these characteristics in women and the prognosis and severity of the disease. Comparisons were established with standard statistics and survival analysis, including crude and multivariate Cox-regression analysis.
Results: Overall, 5355 (31.2%) women were compared with men with COPD. Women were younger, had lower pack-years, greater FEV1%, lower BMI and a greater number of exacerbations (all p < 0.05). On symptoms, women reported more dyspnea, equal cough but less expectoration (p < 0.001). There were no differences in the BODE index score in women (2.4) versus men (2.4) (p = 0.5), but the distribution of all BODE components was highly variable by sex within different thresholds of BODE. On prognosis, 5-year survival was higher in COPD females (86.9%) than in males (76.3%), p < 0.001, in all patients and within each of the specific comorbidities that we assessed. The crude and adjusted RR and 95% C.I. for death in males was 1.82 (1.69–1.96) and 1.73 (1.50–2.00), respectively.
Conclusions: COPD in women has some characteristic traits expressed differently than compared to men, mainly with more dyspnea and COPD exacerbations and less phlegm, among others, although long-term survival appears better in female COPD patients
Transcriptomic differences in MSA clinical variants
Background: Multiple system atrophy (MSA) is a rare oligodendroglial synucleinopathy of unknown etiopathogenesis including two major clinical variants with predominant parkinsonism (MSA-P) or cerebellar dysfunction (MSA-C). Objective: To identify novel disease mechanisms we performed a blood transcriptomic study investigating differential gene expression changes and biological process alterations in MSA and its clinical subtypes. Methods: We compared the transcriptome from rigorously gender and age-balanced groups of 10 probable MSA-P, 10 probable MSA-C cases, 10 controls from the Catalan MSA Registry (CMSAR), and 10 Parkinson Disease (PD) patients. Results: Gene set enrichment analyses showed prominent positive enrichment in processes related to immunity and inflammation in all groups, and a negative enrichment in cell differentiation and development of the nervous system in both MSA-P and PD, in contrast to protein translation and processing in MSA-C. Gene set enrichment analysis using expression patterns in different brain regions as a reference also showed distinct results between the different synucleinopathies. Conclusions: In line with the two major phenotypes described in the clinic, our data suggest that gene expression and biological processes might be differentially affected in MSA-P and MSA-C. Future studies using larger sample sizes are warranted to confirm these results
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