162 research outputs found
A Probabilistic Approach to the Drag-Based Model
The forecast of the time of arrival of a coronal mass ejection (CME) to Earth
is of critical importance for our high-technology society and for any future
manned exploration of the Solar System. As critical as the forecast accuracy is
the knowledge of its precision, i.e. the error associated to the estimate. We
propose a statistical approach for the computation of the time of arrival using
the drag-based model by introducing the probability distributions, rather than
exact values, as input parameters, thus allowing the evaluation of the
uncertainty on the forecast. We test this approach using a set of CMEs whose
transit times are known, and obtain extremely promising results: the average
value of the absolute differences between measure and forecast is 9.1h, and
half of these residuals are within the estimated errors. These results suggest
that this approach deserves further investigation. We are working to realize a
real-time implementation which ingests the outputs of automated CME tracking
algorithms as inputs to create a database of events useful for a further
validation of the approach.Comment: 18 pages, 4 figure
Cytochrome bd as antioxidant redox enzyme
One of the main functions of enzyme complexes that constitute electron transport (respiratory) chains of organisms is to maintain cellular redox homeostasis by oxidizing reducing equivalents, NADH and quinol. Cytochrome bd is a unique terminal oxidase of the chains of many bacteria including pathogenic species. This redox enzyme couples the oxidation of ubiquinol or menaquinol by molecular oxygen to the generation of proton motive force, a universal energy
currency. The latter is used by the organism to produce ATP, another cellular energy currency, via oxidative phosphorylation. Escherichia coli contains two bd–type oxidases, bd-I and bd-II, encoded by the cydAB and appCB operons, respectively. Surprisingly, both bd enzymes make a further contribution to molecular mechanisms of maintaining the appropriate redox balance in
the bacterial cell by means of elimination of reactive oxygen species, such as hydrogen peroxide. This review summarizes recent data on the redox-modulated H 2 O 2 -scavenging activities of cytochromes bd-I and bd-II from E. coli. The possibility of such antioxidant properties in cytochromes bd from other bacteria is also discussed
The Impact of Exercise Intervention with Rhythmic Auditory Stimulation to Improve Gait and Mobility in Parkinson Disease: An Umbrella Review
Difficulties in walking, controlling balance, and performing activities of daily living are common problems encountered by individuals affected by Parkinson disease. Scientific evidence suggests that exercise performed with music or auditory or rhythmical cues facilitates movement and improves balance, gait, mobility, and activities of daily living (ADL) performance in patients with PD. The aim of this umbrella review was to summarize available high-quality evidence from systematic reviews and meta-analyses on the effectiveness of rhythmically cued exercise to improve gait, mobility, and ADL performance in individuals with PD. PubMed, Cochrane, and Embase databases were searched from January 2010 to October 2020 for systematic reviews and meta-analyses which had to be (1) written in English, (2) include studies on populations of males and females with PD of any age, (3) analyze outcomes related to gait, mobility, and ADL, and (4) apply exercise interventions with music or auditory or rhythmical cues. Two independent authors screened potentially eligible studies and assessed the methodological quality of the studies using the AMSTAR 2 tool. Four studies, two systematic reviews and meta-analyses, one a systematic review, and one a meta-analysis, were selected. Overall results indicated positive effects for gait and mobility of the use of rhythmic auditory cueing with exercise and suggested that it should be incorporated into a regular rehabilitation program for patients affected by PD. Nonetheless, more primary level research is needed to address the identified gaps regarding the application of this method to physical exercise interventions
Materials recovery from waste liquid crystal displays: A focus on indium
In the present work the recovery of indium and of the polarizing film from waste liquid crystal displays was experimentally investigated in the laboratory. First of all, the polarizing film was removed by employing a number of different techniques, including thermal and chemical treatments. Leaching of indium was then performed with HCl 6 N, which allowed solubilisation of approximately 90% In (i.e. 260 mg In per kg of glass) at room temperature, without shredding. Indium recovery from the aqueous phase was then investigated through solvent extraction with polyethylene glycol (PEG)-based aqueous biphasic systems. Indium extraction tests through the PEG-ammonium sulphate-water system were conducted as a function of PEG concentration, salt concentration and molecular weight of PEG, using 1,10 phenanthroline as a ligand. The experimental results demonstrated that indium partitioning between the bottom (salt-rich) and the top (PEG-rich) phase is quite independent on the composition of the system, since 80-95% indium is extracted in the bottom phase and 5-20% in the top phase; it was also found that when PEG concentration is increased, the ratio between the bottom and the upper phase volumes decreases, resulting in an increase of indium concentration in the bottom phase (at [PEG]=25% w/w, indium concentration in the bottom phase is ~30% higher than the initial concentration before the extraction)
Electronic witness system in IVF—patients perspective
Objective The objective of this study is to evaluate patient
concerns about in vitro fertilization (IVF) errors and electronic
witness systems (EWS) satisfaction.
Design The design of this study is a prospective single-center
cohort study.
Setting The setting of this study was located in the private
IVF center.
Patient(s) Four hundred eight infertile patients attending an
IVF cycle at a GENERA center in Italy were equipped with an
EWS.
Intervention(s) Although generally recognized as a very rare
event in IVF, biological sample mix-up has been reported in
the literature. For this reason, some IVF laboratories have
introduced EWS with the aim to further reduce the risk of
error during biological samples handling. Participating
patients received a questionnaire developed through a Likert
scale ranging from 1 to 6.
Main outcomes measure(s) Patient concerns about sample
mix-up without and with an EWS were assessed.
Result(s) 90.4 % of patients expressed significant concerns
relating to sample mix-up. The EWS reduced these concerns
in 92.1 % of patients, 97.1 % of which were particularly satisfied with the electronic traceability of their gametes and
embryos in the IVF laboratory. 97.1 % of patients felt highly
comfortable with an IVF center equipped with an EWS.
Female patients had a significantly higher appreciation of
the EWS when compared to their male partners (p = 0.029).
A significant mix-up event occurred in an Italian hospital during the study and patient's satisfaction increased significantly
towards the use of the EWS after the event (p = 0.032).
Conclusion(s) EWS, by sensibly reducing the risk for sample
mix-up in IVF cycles, has been proved to be a trusted strategy
from patient's perspective
Desnutrição e desfechos clínicos e nutricionais de pacientes oncológicos atendidos em um ambulatório de nutrição: um estudo transversal
O objetivo deste trabalho foi avaliar a associação entre a Avaliação Subjetiva Global Produzida Pelo Paciente e os desfechos clínicos e nutricionais. Foi realizado um estudo transversal, retrospectivo, com pacientes atendidos em Ambulatório de Nutrição e Oncologia, entre Janeiro de 2018 a Janeiro de 2020. Foram incluídos adultos com diagnóstico de câncer hematológico ou tumor sólido. Os dados demográficos e clínicos foram coletados a partir de prontuário eletrônico e os dados nutricionais e sintomas coletados através da ficha de anamnese. A relação entre variáveis categóricas foi avaliada pelos testes do qui-quadrado ou exato de Fischer, e de variáveis contínuas através dos testes de Pearson ou correlação de Spearman. O nível de significância utilizado foi de 5%. Foram avaliados 260 pacientes, sendo 51,5% do sexo feminino e 84,2% de raça branca, com idade média de 59 anos. Em relação ao diagnóstico nutricional, 41,5% dos pacientes eram bem nutridos, 39,6% apresentavam suspeita de desnutrição ou desnutrição moderada e 18,8% eram desnutridos graves. Observou-se associação significativa entre pacientes com desnutrição e os seguintes desfechos: idade, óbito, tipo de câncer, em especial, esôfago, pulmão e cólon, presença de diabetes melito, tipo de tratamento clínico e via alimentar. Também foi observada associação significativa com os sintomas de disfagia, odinofagia, saciedade precoce, alteração do paladar, xerostomia e inapetência quando comparado os pacientes desnutridos com os classificados como bem nutrido.
Cytogenetic and molecular characterization of durum wheat chromosome transfers with 1D-associated gluten protein genes and their pyramiding
Gluten quality of bread wheat is known to be mainly associated with high- (HMW-GS) and low-(LMW-GS) molecular weight glutenin subunits encoded by Glu-1 (L arm of group-1 chromosomes) and Glu-3 (S arm of group-1 chromosomes) genes, respectively, with the 1D alleles of such genes having the major impact on bread making properties. Transfer of chromosomal segments containing the Glu-D1 and Gli-D1/Glu-D3 loci was successfully achieved in a number of instances resorting to chromosome engineering. Using this strategy, we isolated two 1A-1D recombinant lines, in which the Gli-D1/Glu-D3 genes and the Glu-D1d allele (HMW-GS "5+10") were separately transferred into the 1AS and 1AL arm, respectively, of recipient durum wheat lines (named PS and PL, respectively). Also, a detailed genetic map of both recombinant chromosome arms was developed. Stable PS + PL double-recombinant lines have been obtained as a result of homologous recombination in the 1A portions shared by the two recombinant chromosomes present in PS x PL hybrids. Preliminary quality tests suggest that the Glu-D3 + Glu-D1d combined presence could determine a slight increase of gluten quality parameters over those associated with Glu-D1d alone
Efficacy and Safety of Bempedoic Acid in Patients With Hypercholesterolemia: Systematic Review and Meta‐Analysis of Randomized Controlled Trials
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