397 research outputs found
Augmented-LSTM and 1D-CNN-LSTM based DPD models for linearization of wideband power amplifiers
Abstract. Artificial Neural Networks (ANNs) have gained popularity in modeling the nonlinear behavior of wideband power amplifiers. Recently, modern researchers have used two types of neural network architectures, Long Short-Term Memory (LSTM) and Convolutional Neural Network (CNN), to model power amplifier behavior and compensate for power amplifier distortion. Each architecture has its own advantages and limitations. In light of these, this study proposes two digital pre-distortion (DPD) models based on LSTM and CNN. The first proposed model is an augmented LSTM model, which effectively reduces distortion in wideband power amplifiers. The measurement results demonstrate that the proposed augmented LSTM model provides better linearization performance than existing state-of-the-art DPDs designed using ANNs. The second proposed model is a 1D-CNN-LSTM model that simplifies the augmented LSTM model by integrating a CNN layer before the LSTM layer. This integration reduces the number of input features to the LSTM layer, resulting in a low-complexity linearization for wideband PAs. The measurement results show that the 1D-CNN-LSTM model provides comparable results to the augmented LSTM model. In summary, this study proposes two novel DPD models based on LSTM and CNN, which effectively reduce distortion and provide low-complexity linearization for wideband PAs. The measurement results demonstrate that both models offer comparable performance to existing state-of-the-art DPDs designed using ANNs
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Meal fatty acids have differential effects on postprandial blood pressure and biomarkers of endothelial function but not vascular reactivity in postmenopausal women in the Randomized Controlled Dietary Intervention and VAScular function (DIVAS)-2 Study
Background: Elevated postprandial triacylglycerol concentrations, impaired vascular function and hypertension are important independent cardiovascular disease (CVD) risk factors in women. However, the effects of meal fat composition on postprandial lipemia and vascular function in postmenopausal women are unknown.
Objective: This study investigated the impact of sequential meals rich in saturated (SFAs), monounsaturated (MUFAs) or n-6 polyunsaturated fatty acids (PUFAs) on postprandial flow-mediated dilatation (FMD, primary outcome measure), vascular function and associated CVD risk biomarkers (secondary outcomes) in postmenopausal women.
Methods: A double-blind, randomized, cross-over, postprandial study was conducted with 32 postmenopausal women (58 ± 1 years, BMI 25.9 ± 0.7 kg/m2). After fasting overnight, participants consumed high-fat meals at breakfast (0 min; 50 g fat, containing 33-36 g SFAs, MUFAs or n-6 PUFAs) and lunch (330 min; 30 g fat, containing 19-20 g SFAs, MUFAs or n-6 PUFAs), on separate occasions. Blood samples were collected before breakfast and regularly after the meals for 480 min, with specific time points selected for measuring vascular function and blood pressure.
Results: Postprandial FMD, laser Doppler imaging and digital volume pulse responses were not different after consuming the test fats. The incremental AUC (IAUC) for diastolic blood pressure was lower (-0.5-fold) after the MUFA than SFA-rich meals (P=0.009), with a similar trend for systolic blood pressure (-0.4-fold; P=0.012). This corresponded with a lower IAUC (-6.4-fold) for the plasma nitrite response after the SFA than MUFA-rich meals (P=0.010). The soluble intercellular adhesion molecule-1 (sICAM-1) time course profile, AUC and IAUC were lower after the n-6 PUFA than SFA and MUFA-rich meals (P≤0.001). Lipids, glucose and markers of insulin sensitivity did not differ between the test fats.
Conclusions: Our study revealed a differential impact of meal fat composition on blood pressure, plasma nitrite and sICAM-1, but no effect on postprandial FMD or lipemia in postmenopausal women
Development of an integrated BIM and lean maturity model
The level of Building Information Modelling (BIM) and Lean adoption has been rapidly increased. The benefits of integrating these two approaches have also been identified. However, to achieve the maximum benefits of the interaction of these two approaches, there needs to be assessment tools to analyse their performances collectively. Because understanding and analysing the performances of these approaches would provide value to the entire project in terms of lessons learned, more value generation, and continuous improvements. Therefore, this paper aims to propose an integrated BIM and Lean Maturity Model based on reviewing the literature around current maturity models. This paper proposes an Integrated BIM and Lean Maturity Model named “IDEAL” which could serve as a basis in terms of assessing the performances of the projects implementing BIM and Lean together
Barriers to help-seeking from healthcare professionals amongst women who experience domestic violence:A qualitative study in Sri Lanka
BACKGROUND: Domestic violence (DV) is a major global public health problem which is associated with significant adverse consequences. Although Sri Lankan women who experience DV receive treatment from healthcare professionals (HCPs) for DV related physical and psychological problems, disclosure of DV within health services is quite low. This study explored barriers to disclosure of DV to HCPs among Sri Lankan women who experience DV. METHOD: This qualitative study took place in the Central Province of Sri Lanka. Twenty women who had experienced DV were recruited from Gender Based Violence Centers (Mithuru Piyasa Centers) and a toxicology unit of the two selected hospitals. Participants were purposefully selected using maximum variation sampling technique. In-depth interviews were conducted until data saturation was reached. Interviews were recorded, and analyzed using thematic analysis. RESULTS: Survivor related barriers to help seeking included women’s lack of knowledge and perceptions about the role of HCPs, lack of confidence in HCPs, fear of repercussions, personal attitudes towards DV, and their love and loyalty towards the perpetrator. Women preferred it if HCPs initiated discussions about DV, and they valued it when HCPs could be confidential and protect their privacy, and give enough time for DV related issues during consultations. A perpetrator related barrier was the controlling behavior of the perpetrator. Social stigma and social and cultural norms about the role of women emerged as the socio-cultural constraints to disclosure. CONCLUSIONS: Barriers to help seeking for DV from HCPs exist at individual, healthcare level, and societal level. Community programs are needed to increase women’s access to healthcare services and interventions should be implemented to develop effective, preventive, and supportive strategies at the healthcare system level. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1186/s12889-022-13116-w
Impact of the apolipoprotein E (epsilon) genotype on cardiometabolic risk markers and responsiveness to acute and chronic dietary fat manipulation
Apolipoprotein (APO) E (ε) genotype is considered to play an important role in lipid responses to dietary fat manipulation but the impact on novel cardiometabolic risk markers is unclear. To address this knowledge gap, we investigated the relationship between the APOE genotype and cardiometabolic risk markers in response to acute and chronic dietary fat intakes. Associations with fasting (baseline) outcome measures (n = 218) were determined using data from the chronic DIVAS (n = 191/195 adults at moderate cardiovascular disease risk) and acute DIVAS-2 (n = 27/32 postmenopausal women) studies examining the effects of diets/meals varying in saturated, polyunsaturated and monounsaturated (MUFA) fatty acid composition. Participants were retrospectively genotyped for APOE (rs429358, rs7412). For baseline cardiometabolic outcomes, E4 carriers had higher fasting total and low-density lipoprotein-cholesterol (LDL-C), total cholesterol: high-density lipoprotein-cholesterol (HDL-C) and LDL-C: HDL-C ratios, but lower C-reactive protein (CRP) than E3/E3 and E2 carriers (p ≤ 0.003). Digital volume pulse stiffness index was higher in E2 carriers than the E3/E3 group (p = 0.011). Following chronic dietary fat intake, the significant diet × genotype interaction was found for fasting triacylglycerol (p = 0.010), with indication of a differential responsiveness to MUFA intake between the E3/E3 and E4 carriers (p = 0.006). Test fat × genotype interactions were observed for the incremental area under the curve for the postprandial apolipoprotein B (apoB; p = 0.022) and digital volume pulse reflection index (DVP-RI; p = 0.030) responses after the MUFA-rich meals, with a reduction in E4 carriers and increase in the E3/E3 group for the apoB response, but an increase in E4 carriers and decrease in the E3/E3 group for the DVP-RI response. In conclusion, baseline associations between the APOE genotype and fasting lipids and CRP confirm previous findings, although a novel interaction with digital volume pulse arterial stiffness was observed in the fasted state and differential postprandial apoB and DVP-RI responses after the MUFA-rich meals. The reported differential impact of the APOE genotype on cardiometabolic markers in the acute and chronic state requires confirmation
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High prevalence of undernutrition and low dietary diversity in institutionalised elderly living in Sri Lanka
This research received no specific grant from any funding agency in the public, commercial and not-for-profit sectors. The authors wish to thank the participants, administrators and caregivers of the homes for elders for their enthusiastic cooperation and also the Nutrition Research Team of the Department of Applied Nutrition, Wayamba University of Sri Lanka, for their valuable assistance during the course of the study. The authors also wish to thank Mr. S. Rahanan for coordination and the assistance given in data collection especially in Tamil speaking participants. K.M.R designed and managed the study, interpreted the data and drafted the manuscript. M.P.P.M contributed to the data collection, data analysis and coordination of the study. M.W, K.G.J and J.A.L assisted in data interpretation and critical revision of the manuscript. The authors declare that there is no conflict of interest of any kind involved in this study or this publication.
Ethical clearance for this study was obtained from the Ethical Review Committee of the Sri Lanka Medical Association (ERC/13-037)
Single-nucleotide polymorphism rs2070600 regulates AGER splicing and the sputum levels of the COPD biomarker soluble receptor for advanced glycation end-products.
The COPD susceptibility SNP rs2070600 affects the levels of the COPD biomarker sRAGE in sputum as well as splicing of AGER. Moreover, @PouwelsScience et al. demonstrate large differences in sRAGE levels between serum and sputum. https://bit.ly/3t0pJtK
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