9,151 research outputs found
Design of a THz-MEMS frequency selective surface for structural health monitoring
This paper characterizes the relationship between applied force and reflectance/ transmittance of a terahertz frequency selective surface for use as a sensor in structural health monitoring. Numerical modelling of both the mechanical and electromagnetics, solving the elasticity equation and Maxwell’s equations, respectively, has been undertaken for a 3 layer device. The unit cell comprises of a metal cross wire embedded within a (hard) silicon substrate, interleaved with stacks of (soft) low density polyethylene
Projetos temáticos como alternativa para um ensino contextualizado das ciências : análise de um caso
Prognosis following acute coronary syndromes according to prior coronary artery bypass grafting: Meta-analysis
PURPOSE:
Conduct a meta-analysis to study the prognostic influence of a previous coronary artery bypass grafting (CABG) in patients admitted for an acute coronary syndrome (ACS).
METHODS:
A systematic review of the literature was performed using electronic reference databases through January 2013 (MEDLINE, Cochrane Library, Web of Knowledge, Google Scholar and references cited in other studies). Studies in which ACS outcomes with a previous history of CABG were compared with ACS outcomes with no history of previous CABG were considered for inclusion. The main endpoints of interest were mortality and non-fatal acute myocardial infarction. Data was aggregated at three follow-up times using random-effects meta-analysis models.
RESULTS:
Twenty-four studies were included which provided 387,181 patients for analysis. Previous CABG ACS patients were older, more diabetic and had a more frequent history of a previous myocardial infarction. Pooled in-hospital mortality was higher for the previous CABG ACS patients (OR 1.22 [1.04-1.44], p<0.01, I(2) 88%). The pooled adjusted OR showed no significant differences for the two groups (adjusted OR 1.13 [0.93-1.37], p=0.22, I(2) 92%). Previous CABG ACS patient had a higher pooled 30-day mortality (OR 1.28 [1.05-1.55], p=0.02, I(2) 74%); a higher non-adjusted (OR 1.61 [1.38-1.88], p<0.01, I(2) 70%) and adjusted (adjusted OR 1.37 [1.15-1.65], p<0.01, I(2) 0%) long-term mortality. Both the in-hospital and the long-term re-infarction rates were higher for the previous CABG ACS patients.
CONCLUSIONS:
According to our data, ACS patients with previous CABG history had a higher risk for short- and long-term adverse events
the case of ischemic heart disease in Portugal, 2002–2015
The magnitude of the impact of technological innovations on healthcare expenditure is unclear. This paper estimated the impact of high-technology procedures on public healthcare expenditure for patients with ischemic heart disease (IHD) in Portugal. The Blinder–Oaxaca decomposition method was applied to Portuguese NHS administrative data for IHD discharges during two periods, 2008–2015 vs. 2002–2007 (N = 434,870). We modelled per episode healthcare expenditures on the introduction of new technologies, adjusting for GDP, patient age, and comorbidities. The per episode healthcare expenditure was significantly higher in 2008–2015 compared to 2002–2007 for IHD discharges. The increase in the use of high-technology procedures contributed to 28.6% of this growth among all IHD patients, and to 18.4%, 6.8%, 11.1%, and 29.2% for acute myocardial infarction, unstable angina, stable angina, and other IHDs, respectively. Changes in the use of stents and embolic protection and/or coronary brachytherapy devices were the largest contributors to expenditure growth. High-technology procedures were confirmed as a key driver of public healthcare expenditure growth in Portugal, contributing to more than a quarter of this growth.publishersversionpublishe
Socially responsible consumers and stockpiling during crises: the intersection of personal norms and fear
Purpose - Urging people to avoid stockpiling was a common declaration made by governments during the COVID-19 pandemic outbreak, yet empty supermarket shelves and supply shortages of basic products were observed worldwide. This study aims to (a) identify the factors that activate consumer personal norms towards socially responsible behaviours, specifically resisting stockpiling, and (b) examine how fear moderates the link between personal norms and consumer engagement in stockpiling during public crises. Design/methodology/approach - The study recruited a sample of US consumers who were responsible for household grocery shopping during the COVID-19 pandemic. A total of 593 individuals participated in the study, and the collected data were analysed using structural equation modelling. Findings - The results show that awareness of the negative consequences of stockpiling and a sense of personal responsibility for those consequences activate personal norms towards responsible shopping during public crises. However, perceived fear has the opposite effect, encouraging stockpiling. In addition, fear weakens the negative relationship between personal norms and stockpiling. Originality/value - This study extends the norm activation model and indicates that personal norms may not always promote responsible behaviours when fear is high. It is unique in that it sheds light on non-mainstream responsible consumption behaviours (e.g. resisting stockpiling), and the interaction between consumption and social responsibility
Circulating micrornas correlate with multiple myeloma and skeletal osteolytic lesions
Multiple myeloma (MM) is the second most frequent hematological disease and can cause skeletal osteolytic lesions. This study aims to evaluate the expression of circulating microRNAs (miR-NAs) in MM patients and to correlate those levels with clinicopathological features, including bone lesions. A panel of miRNAs associated with MM onset and progression, or with bone remodeling, was analyzed in the plasma of 82 subjects (47 MM patients; 35 healthy controls). Results show that miR-16-5p, miR-20a-5p, and miR-21-5p are differently expressed between MM patients and healthy controls. Receiver operating characteristic analyses indicate that their combined expression has potential as a molecular marker (Area Under the Curve, AUC of 0.8249). Furthermore, significant correlations were found between the analyzed miRNAs and disease stage, treatment, ß2 microglobulin, serum albumin and creatinine levels, but not with calcium levels or genetic alterations. In this cohort, 65.96% of MM patients had bone lesions, the majority of which were in the vertebrae. Additionally, miR-29c-3p was decreased in patients with osteolytic lesions compared with patients without bone disease. Interestingly, circulating levels of miR-29b-3p correlated with cervical and thoracic vertebral lesions, while miR-195-5p correlated with thoracic lesions. Our findings suggest circulating miRNAs can be promising biomarkers for MM diagnosis and that their levels correlate with myeloma bone disease and osteolytic lesions.The project was supported by AO Spine-ESA Grant Award 2018 (AO Foundation); As-sociação Portuguesa Contra a Leucemia, Sociedade Portuguesa de Hematologia, AMGEN; and by Portuguese funds through FCT-Fundação para a Ciência e a Tecnologia (FCT)/Ministério da Ciência, Tecnologia e Ensino Superior in the framework of the project POCI-01-0145-FEDER-031402-R2Bone (FEDER-Fundo Europeu de Desenvolvimento Regional funds through the COMPETE 2020-Operacional Programme for Competitiveness and Internationalisation—POCI, Portugal 2020)
Surface roughness dependent osteoblast and fibroblast response on poly(l-lactide) films and electrospun membranes
Poly(l-lactide) electrospun mats with random and aligned fiber orientation and films have been produced with degrees of crystallinity ranging from 0 up to nearly 50%. The overall surface roughness is practically constant irrespective of the sampling areas (1 × 1 µm to 20 × 20 µm) for degrees of crystallinity below 30%, increasing for higher degrees of crystallinity for the larger sampling areas. Further, due to fiber confinement, surface roughness variations are smaller in electrospun mats. Samples with 50% of crystallinity show the lowest osteoblast and the highest fibroblast proliferation. Therefore, it is verified that higher roughness promotes lower osteoblast but higher fibroblast proliferation. The overall results indicate the relevant role of the sub-microenvironment variations associated to the microscale roughness in determining the different cell responses.Portuguese Foundation for Science and Technology (FCT); contract grant numbers: C/FIS/UI607/2011, PTDC/CTM-NAN/112574/2009, contract grant numbers: SFRH/BPD/63148/2009, SFRH/BPD/90870/2012, Matepro—Optimizing Materials and Processes, Programa Operacional Regional do Norte, Quadro de Referência
Estratégico Nacional” (QREN), “Fundo Europeu de Desenvolvimento Regional” (FEDER); contract grant number: NORTE-07–0124-FEDER-000037
Towards Studying Hierarchical Assembly in Real Time: A Milky Way Progenitor Galaxy at z = 2.36 under the Microscope
We use Hubble Space Telescope (HST) imaging and near-infrared spectroscopy
from Keck/MOSFIRE to study the sub-structure around the progenitor of a Milky
Way-mass galaxy in the Hubble Frontier Fields (HFF). Specifically, we study an
pc, rest-frame
ultra-violet luminous "clump" at a projected distance of 100~pc from a
M galaxy at with a magnification
. We measure the star formation history of the clump and galaxy by
jointly modeling the broadband spectral energy distribution from HST photometry
and H from MOSFIRE spectroscopy. Given our inferred properties (e.g.,
mass, metallicity, dust) of the clump and galaxy, we explore scenarios in which
the clump formed \emph{in-situ} (e.g., a star forming complex) or
\emph{ex-situ} (e.g., a dwarf galaxy being accreted). If it formed
\emph{in-situ}, we conclude that the clump is likely a single entity as opposed
to a aggregation of smaller star clusters, making it one of the most dense star
clusters cataloged. If it formed \emph{ex-situ}, then we are witnessing an
accretion event with a 1:40 stellar mass ratio. However, our data alone are not
informative enough to distinguish between \emph{in-situ} and \emph{ex-situ}
scenarios to a high level of significance. We posit that the addition of
high-fidelity metallicity information, such as [OIII]4363\AA, which can be
detected at modest S/N with only a few hours of JWST/NIRSpec time, may be a
powerful discriminant. We suggest that studying larger samples of moderately
lensed sub-structures across cosmic time can provide unique insight into the
hierarchical formation of galaxies like the Milky Way.Comment: Accepted to MNRA
Association of PDE11A global haplotype with major depression and antidepressant drug response
Cyclic nucleotide phosphodiesterases (PDEs) hydrolyze the intracellular second messengers cAMP and cGMP to their corresponding monophosphates. PDEs play an important role in signal transduction by regulating the intracellular concentration of cyclic nucleotides. We have previously shown that the individual haplotype GAACC in the PDE11A gene was associated with major depressive disorder (MDD) based on block-by-block analysis. There are two PDE genes, PDE11A and PDE1A, located in chromosome 2q31–q32. In this study, we have further explored whether the whole region 2q31–q32 contribute to MDD or antidepressant response 278 depressed Mexican-American participants and 321 matched healthy controls. Although there is no significant interaction between the two genes, the remission rate of individual carrying the combination genotype at rs1880916 (AG/AA) and rs1549870 (GG) is significantly increased. We analyzed the global haplotype by examining 16 single-nucleotide polymorphisms (SNPs) in PDE11A and six SNPs in PDE1A. None of the haplotypes consisting of six SNPs in the PDE1A have a significant difference between depressed and control groups. Among haplotypes consisting of 16 SNPs across 440 kb in the PDE11A gene, 18 common haplotypes (with frequency higher than 0.8%) have been found in the studied population. Six haplotypes showed significantly different frequencies between the MDD group and the control group. The phylogenetic network result for the 16 SNPs showed that several historic recombination events have happened in the PDE11A gene. The frequency of one haplotype is significantly lower in the remitter group than in the nonremitter group for the depressed participants treated with either desipramine or fluoxetine. Thus, our data suggest that the PDE11A global haplotype is associated with both MDD and antidepressant drug response
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