Maternal obesity is associated with the formation of small dense LDL and hypoadiponectinemia in the third trimester

Context: Maternal obesity is associated with high plasma triglyceride, poor vascular function, and an increased risk for pregnancy complications. In normal-weight pregnant women, higher triglyceride is associated with increased small, dense low-density lipoprotein (LDL). Hypothesis: In obese pregnancy, increased plasma triglyceride concentrations result in triglyceride enrichment of very low-density lipoprotein-1 particles and formation of small dense LDL via lipoprotein lipase. Design: Women (n = 55) of body mass index of 18–46 kg/m2 were sampled longitudinally at 12, 26, and 35 weeks' gestation and 4 months postnatally. Setting: Women were recruited at hospital antenatal appointments, and study visits were in a clinical research suite. Outcome Measures: Plasma concentrations of lipids, triglyceride-rich lipoproteins, lipoprotein lipase mass, estradiol, steroid hormone binding globulin, insulin, glucose, leptin, and adiponectin were determined. Results: Obese women commenced pregnancy with higher plasma triglyceride, reached the same maximum, and then returned to higher postnatal levels than normal-weight women. Estradiol response to pregnancy (trimester 1–3 incremental area under the curve) was positively associated with plasma triglyceride response (r2 adjusted 25%, P < .001). In the third trimester, the proportion of small, dense LDL was 2-fold higher in obese women than normal-weight women [mean (SD) 40.7 (18.8) vs 21.9 (10.9)%, P = .014], and 35% of obese, 14% of overweight, and none of the normal-weight women displayed an atherogenic LDL subfraction phenotype. The small, dense LDL mass response to pregnancy was inversely associated with adiponectin response (17%, P = .013). Conclusions: Maternal obesity is associated with an atherogenic LDL subfraction phenotype and may provide a mechanistic link to poor vascular function and adverse pregnancy outcome

Preeclampsia is associated with compromized maternal synthesis of long chain polyunsaturated fatty acids leading to offspring deficiency

Obesity and excessive lipolysis are implicated in preeclampsia (PE). Intrauterine growth restriction is associated with low maternal body mass index and decreased lipolysis. Our aim was to assess how maternal and offspring fatty acid metabolism is altered in mothers in the third trimester of pregnancy with PE (n=62) or intrauterine growth restriction (n=23) compared with healthy pregnancies (n=164). Markers of lipid metabolism and erythrocyte fatty acid concentrations were measured. Maternal adipose tissue fatty acid composition and mRNA expression of adipose tissue fatty acid–metabolizing enzymes and placental fatty acid transporters were compared. Mothers with PE had higher plasma triglyceride (21%, P<0.001) and nonesterified fatty acid (50%, P<0.001) concentrations than controls. Concentrations of major n−6 and n−3 long-chain polyunsaturated fatty acids in erythrocytes were 23% to 60% lower (all P<0.005) in PE and intrauterine growth restriction mothers and offspring compared with controls. Subcutaneous adipose tissue Δ−5 and Δ−6 desaturase and very long-chain fatty acid elongase mRNA expression was lower in PE than controls (respectively, mean [SD] control 3.38 [2.96] versus PE 1.83 [1.91], P=0.030; 3.33 [2.25] versus 1.03 [0.96], P<0.001; 0.40 [0.81] versus 0.00 [0.00], P=0.038 expression relative to control gene [square root]). Low maternal and fetal long-chain polyunsaturated fatty acid concentrations in PE may be the result of decreased maternal synthesis

Disturbed sleep and quality of life in female Fibromyalgia patients

Fibromyalgia is a musculoskeletal disorder that mainly affects women. One of the main symptoms of this disorder is poor sleep quality. The aim of this study is to determine how sleep quality and quality of life are related to female fibromyalgia patients versus healthy controls.This paper was initially delivered at the Annual Congress of the Biological Sciences Division of the South African Academy for Science and Art, ARC-Plant Protection Research Institute, Roodeplaat, Pretoria, South Africa on 01 October 2010.http://www.satnt.ac.zaam2014ay201

Survey response in colorectal surgery:A systematic review

Background: Survey research is widely used for developing value-based management strategies in colorectal surgery. However, declining response rates threaten the validity of results. Our aim is to identify factors that influence response rate in colorectal surgical surveys and provide recommendations for future survey design.Methods: We performed a (MEDLINE) search between 2007 and 2020 for survey studies in colorectal surgery providing response rates.Results: Our search revealed 5693 studies, of which 128 studies were included. Patients with colorectal cancer have a lower mean response rate than patients with benign pathology (62.8% vs 75.5%, p &lt; 0.001). Response rate depends on the mode of survey; conducted in person (76%), postal (68%), email (61%) and web-based (44%). Patients participate more often than doctors (P &lt; 0.001). Reminders can positively influence response rates in postal patient surveys (p = 0.03). The proportion of web-based doctor surveys has grown over time (p &lt; 0.01) and overall survey response is declining over time (p = &lt; 0.01).Conclusion: In-person surveying should be explored first in colorectal surgery, especially when addressing colorectal cancer patients and doctors. Reminders are useful to boost response rate in postal surveys directed at patients. Web-based doctor surveys generate the lowest response rate. As response rate is declining, it is important to address these factors when designing and reviewing colorectal surgical survey studies.</p

Paläofluide in störungskontrollierten Bruchsystemen der Aachener Geothermie-Bohrung

In der vorliegenden Arbeit werden geologische Prozesse im Untergrund des linksrheinischen Rhenoherzynikums und deren Verhältnis zum regionaltektonischen Rahmen anhand der Proben aus der Aachener Geothermie- Bohrung mit dem Schwerpunkt des Fluid- und Stofftransportes untersucht. Die methodische Vorgehensweise basiert auf einer systematischen und detaillierten Bestandsaufnahme der Paläofluide in Form von Flüssigkeitseinschlüssen an Kernmaterial der Bohrung. Im Aachener Raum wurden Untersuchungen von Flüssigkeitseinschlüssen hauptsächlich an postvariszischen Pb-Zn-Gangvorkommen durchgeführt. Die Homogenisierungstemperaturen (Th) von NaCl-CaCl2-Lösungen unterschiedlicher Salinität liegen zwischen 70°C und maximal 190°C (Redecke 1992, Stroink 1993, Muchez et al. 1994, Glasmacher 1995). Für die tektonischmetallogentische Entwicklung des Rheinischen-Schiefergebirges können generell zwei Fluid-Aktivitätsperioden unterschieden werden (Behr et al. 1993). Die im Zuge der variszischen Gebirgsbildung synkinematische Defluidisierung des Orogenkörpers generierte das Fluid-System der ‚Tectonic Brines‘ (1). Diese sind Na-(K)-Cl-betonte Lösungen geringer Salinität mit CO2, CH4 und N2 sowie durch Th < 350°C gekennzeichnet. Im Gegensatz dazu wurden die meisten postvariszischen Ganglagerstätten des Rheinischen- Schiefergebirges durch ‚Basement Brines‘ (2) gebildet. Diese sind Ca- Na-Cl-Lösungen hoher Salinität mit Th < 250°C (Behr et al. 1993).conferenc

Modeling a porous region for natural convection heat transfer and experimental validation in slender cylindrical geometries

Natural convection heat transfer in fluid-saturated porous media has in recent years gained considerable attention especially in high-temperature reactors. It is proposed in this study that light water reactors (LWRs) can be made safer by redesigning the fuel in the fuel assembly. The proposed design is aimed at increasing the safety level in LWRs by the use of fuel in the form of loose coated particles in a helium environment inside the nuclear fuel cladding tubes of the fuel elements. The coated particle fuel being a heat source forms a bed in the cladding tube closed at both ends, the heat from the particles is transferred to the gas in the tube, and the gas movement is due to natural convection. In this study, we investigate the heat transfer characteristics inside a cladding tube containing packed beds of spherical particles by simulating a porous region whose medium properties are defined; that is, the geometrical model representing the packed bed is specified as a porous region. The finite volume method was used in solving the three-dimensional Navier-Stokes equation while the heat transfer coefficient h and the dimensionless numbers such as Ra f(Gr, Pr) and Nu are used in analyzing the results. Simulated results from this investigation were validated with experimental results. The discrepancy in the results may be due to uncertainties, experimental errors, numerical errors, and the consequence of the lump parameter effect in the porous region modeling approach. This approach may be considered a unique means of estimating heat transfer characteristics in porous media.The Department of Mechanical and Aeronautical Engineering, University of Pretoria, Pretoria, South Africa.http://www.ans.org/pubs/journals/ntam2017Mechanical and Aeronautical Engineerin

Numerical study on natural convection of MWCNT nanofluids in a enclosure based on experimental conductivity and viscosity

Papers presented to the 11th International Conference on Heat Transfer, Fluid Mechanics and Thermodynamics, South Africa, 20-23 July 2015.This study is motivated by the much reported enhancement in thermal conductivity of nanofluids and their potential as a replacement for conventional coolant fluids. Among the various factors considered in the selection of a coolant fluid, this study focused on the convective behaviour of nanofluids as demonstrated in a square enclosure with differentially heated side walls at low particle concentrations of 0 – 1 % and Ra number range of 104 to 106. Therefore, the study consists of numerical investigation by using experimentally determined thermal conductivities and viscosities of the nanofluid. A theoretical model was used for higher (though less practical) particle concentration of up to 8 %. The simulations were done by using CD Adapco’s Star-CCM+ Code (v 8.06) revealed an initial enhancement in the Nusselt number with varying particle concentration before rapidly falling to an average value that continues to diminish for the concentration range tested. This was true for different Ra numbers. The variation was attributed to the counteracting, non-linear effects of thermal conductivity and viscosity both of which increases by increasing particle concentration. The thermal conductivity effect were observed to be more dominant for a very narrow range of low particle concentration below 0.1 % while the viscous effect was found to be the more dominant at higher particle concentration above 0.1 %.am201

Why high tech needs high touch: Supporting continuity of community primary health care

Background: Integrated care through community-oriented primary care (COPC) deployed through municipal teams of community health workers (CHWs) has been part of health reform in South Africa since 2011. The role of COPC and integration of information and communication technology (ICT) information to improve patient health and access to care, require a better understanding of patient social behaviour.   Aim: The study sought to understand how COPC with CHWs visiting households offering health education can support antenatal follow-up and what the barriers for access to care would be.   Method: A mixed methodological approach was followed. Quantitative patient data were recorded on an electronic health record-keeping system. Qualitative data collection was performed through interviews of the COPC teams at seven health posts in Mamelodi and telephonic patient interviews. Interviews were analysed according to themes and summarised as barriers to access care from a social and community perspective.   Results: An integrated COPC approach increased the number of traceable pregnant women followed up at home from 2016 – 2017. Wrong addresses or personal identification were given at the clinic because of fear of being denied care. Allocating patients correctly to a ward-based outreach team (WBOT) proved to be a challenge as many patients did not know their street address.   Conclusion: Patient health data available to a health worker on a smartphone as part of COPC improve patient traceability and follow-up at home making timely referral possible. Health system developments that support patient care on community level could strengthen patient health access and overall health

Microwave-plasma synthesis of nano-sized silicon carbide at atmospheric pressure

A microwave plasma process operating at atmospheric pressure was developed for the synthesis of SiC nanoparticles. The process utilizes methyltrichlorosilane (MTS) as precursor, acting as both carbon and silicon source, along with an additional hydrogen feed to ensure a fully reducing reaction environment. In addition, argon served as carrier gas.. The parameters studied were the H2:MTS molar ratio and the total enthalpy, in the range 0 to 10 and 70 to 220 MJ/kg respectively. The particles size distribution ranged from 15 to 140 nm as determined by SEM and TEM micrographs. It was found that an increase in enthalpy and a higher H2:MTS ratio resulted in smaller SiC particle sizes. The adhesion of particles was a common ocuurence during the process, resulting in larger agglomerate sizes.South African National Research Foundationhttp://www.elsevier.com/locate/ceramint/hb201

Quantum walks: a comprehensive review

Quantum walks, the quantum mechanical counterpart of classical random walks, is an advanced tool for building quantum algorithms that has been recently shown to constitute a universal model of quantum computation. Quantum walks is now a solid field of research of quantum computation full of exciting open problems for physicists, computer scientists, mathematicians and engineers. In this paper we review theoretical advances on the foundations of both discrete- and continuous-time quantum walks, together with the role that randomness plays in quantum walks, the connections between the mathematical models of coined discrete quantum walks and continuous quantum walks, the quantumness of quantum walks, a summary of papers published on discrete quantum walks and entanglement as well as a succinct review of experimental proposals and realizations of discrete-time quantum walks. Furthermore, we have reviewed several algorithms based on both discrete- and continuous-time quantum walks as well as a most important result: the computational universality of both continuous- and discrete- time quantum walks.Comment: Paper accepted for publication in Quantum Information Processing Journa