Consumption of a flavonoid-rich acai meal is associated with acute improvements in vascular function and a reduction in total oxidative status in healthy overweight men

Background: Acai (Euterpe oleracea) is a polyphenol-rich fruit marketed as beneficial for health. Experimental data showing improvements in health markers arising from acai consumption in humans is limited. Objective: The objective of the present study was to investigate the effect of acai consumption on acute changes in vascular function and on other disease risk markers, including postprandial plasma insulin, glucose, and oxidative stress. Design: Twenty-three healthy male volunteers, aged 30–65 y and with a body mass index (in kg/m2) of 25–30, completed a randomized,controlled, high-fat challenge, double-blind, crossover, acute dietary intervention trial. The volunteers consumed either an acai-based smoothie (AS) or a macronutrient-matched control smoothie (PS) together with a high-fat breakfast meal challenge. The primary endpoint was the assessment of endothelial function in the brachial artery by flow-mediated dilatation (FMD). Results: The acute consumption of an AS containing 694 mg total phenolics improved vascular function, with postprandial increases in FMD from baseline of 1.4% at 2 h compared with 0.4% after consumption of the PS (P = 0.001) and increases at 6 h of 0.8% for the AS compared with 20.3% for the PS (P , 0.001). There was also a significantly lower incremental area under the curve (iAUC)for total peroxide oxidative status after acai consumption relative to the control. No significant changes were observed in blood pressure,heart rate, or postprandial glucose response. However, the first postprandial insulin peak (after breakfast) and the iAUC for insulin were elevated for the AS relative to the PS. Conclusions: In this acute study in overweight men, acai consumption was associated with improvements in vascular function, which may lower the risk of a cardiovascular event. Future intervention studies, perhaps with a chronic design, in wider populations and with other biomarkers of disease risk are needed to fully elucidate the benefits of acai to health

An investigation of antecedents and consequences of organisational commitment among government administrative employees in Saudi Arabia

This thesis was submitted for the degree of Doctor of Philosophy and awarded by Brunel University.Organisational commitment, viewed as a measurable psychological state, is a core variable of interest in Organisational Behaviour research. It has been studied for more than four decades, largely focusing on the identification of its antecedents and consequences. One widely used conceptualisation is Meyer and Allen‘s (1991) three-component model of commitment, which considers commitment as having three forms: affective, continuance and normative (emotional attachment to an organisation, the perceived cost associated with leaving it and the perceived obligation to remain in it). This research contributes in three ways to improving our understanding of public-sector work behaviour, with particular reference to organisational commitment. Firstly, it examines the multi-dimensionality of organisational commitment. Secondly, it explores the relationships between Meyer and Allen‘s three components, modifying the concept of continuance commitment to include two sub-components, high personal sacrifice and low perceived alternatives, thus proposing a four-factor model, Antecedents and Consequences of Organisational Commitment Components (ACOCC). Thirdly, it considers antecedent variables, including Hofstede‘s (1980) four cultural dimensions (individualism/collectivism, uncertainty avoidance, power distance and masculinity/femininity), as well as selected consequences: in role behaviour, organisational citizen behaviour and employee intention to leave. These selected variables are deemed to be suitable for Saudi Arabian culture and have never been tested before in that context. The study investigates how the commitment components are associated with and mediate relationships with the set of possible work behaviours. Using a sample of 700 employees from different organisation levels (drawn from 16 Saudi ministries in two cities, Riyadh and Jeddah) the hypotheses were tested through structural equation modelling, which confirmed the fit of the proposed recursive ACOCC model. The regression paths were significant between the antecedents (opportunities for learning, impersonal bureaucratic arrangements and Hofstede‘s four cultural dimensions) and affective and normative commitment, as well as for continuance commitment for reasons of high personal sacrifice. Intention to leave and organisational citizen behaviour were fully mediated by the commitment components. Thus the findings reveal the level and form of organisational commitment among public-sector employees and of relationships between the antecedents and consequences of that commitment in a non-Western culture, specifically Saudi Arabia. In particular, they highlight the significant mediation role of organisational commitment. The findings also permit exploration of a number of issues pertaining to cultural dimensions impacting on organisational commitment. Noteworthy here, for example, is the high degree of uncertainty avoidance found among Saudi public-sector top-level managers. These different results have important implications for the nature and management of commitment among government employees in Saudi Arabia and the Gulf Cooperation Council countries as a whole

In vitro approaches to assess the effects of açai (Euterpe oleracea) digestion on polyphenol availability and the subsequent impact on the faecal microbiota

A considerable proportion of dietary plant-polyphenols reach the colon intact; determining the effects of these compounds on colon-health is of interest. We hypothesise that both fibre and plant polyphenols present in açai (Euterpe oleracea) provide prebiotic and anti-genotoxic benefits in the colon. We investigated this hypothesis using a simulated in vitro gastrointestinal digestion of açai pulp, and a subsequent pH-controlled, anaerobic, batch-culture fermentation model reflective of the distal region of the human large intestine. Following in vitro digestion, 49.8% of the total initial polyphenols were available. In mixed-culture fermentations with faecal inoculate, the digested açai pulp precipitated reductions in the numbers of both the Bacteroides-Prevotella spp. and the Clostridium-histolyticum groups, and increased the short-chain fatty acids produced compared to the negative control. The samples retained significant anti-oxidant and anti-genotoxic potential through digestion and fermentation. Dietary intervention studies are needed to prove that consuming açai is beneficial to gut health

Characterization of CTX-M β-lactamases in Enterobacteriaceae from major teaching hospitals

Escherichia coli and Klebsiella pneumoniae cause a wide range of infections. Multidrug-resistance strains carrying extended-spectrum β-lactamases (ESBLs) has become a growing problem worldwide. The CTX-M type ESBLs has emerged distinctly, especially in Escherichia coli and Klebsiella pneumoniae. CTX-M type has been associated with many outbreaks of infections both in the hospitals and community. CTX-M-15 is now identified as the most predominantly distributed CTX-M enzyme. Clonal outbreaks of CTX-M-15 producing Enterobacteriaceae have been described in many countries including the United Kingdom, and Escherichia coli is the most commonly involved species. A total of 100 isolates were received in 2010 from London St George’s hospital, England, 50 Escherichia coli, 17 Klebsiella spp, 9 Enterobacter spp, 13 Proteus spp, 6 Lactose fermenting coliforms, 2 Pantoea spp, one Serratia marcescens, one Morganella morganii, and one Hafnia alvei. The antimicrobial susceptibility results showed that 5 Escherichia coli and one Klebsiella pneumoniae isolates were found to be resistance to cefotaxime, ceftazidime, ceftriaxone, cefotaxime, ciprofloxacin, and gentamicin, making them multi-drug resistant bacteria. None of the isolates showed resistance to imipenem, ertapenem, or morepenem, thus making carbapenems the drug of choice for the treatment of these infections due to multi-resistant isolates. The overall frequency of CTX-M-15 type ESBL-producers detected in this study was 6 (6%) most of them 5/6 (83%) were from Escherichia coli and one was (17%) Klebsiella pneumoniae isolates. The 6 CTX-M-positive isolates were typed by PFGE, only two strains of Escherichia coli showed more than 85% similarity, owing to clonal homology for both strains. The rest strains showed less than 85% similarity. S1 nuclease plasmid profiles were obtained for ESBL-producers isolates. A total of one to three plasmids per isolate, ranging from approximately 78.0 to 152.0 kb, were observed. The plasmids from most isolates were assigned to be IncFA and IncFB replicons. Analysis of phylogenetic groups showed group A and group B2. The method of phylogenetic classification of exteraintestinal pathogenic Escherichia coli depends on examine and combination of two preserved genes (chuaA and yjaA) and the DNA fragment TSP. Primer walking and PCR experiments were used for the genetic environment studies which showed 5 different genetic constructions for the described blaCTX-M-15 genes. Conjugation studies were used to detect the transferability of the plasmids harbouring the reported blaCTX-M-15 genes. Three isolates were found transferable by conjugation. In conclusion, this study reports the presence of hospital highly resistant blaCTX-M-15 in St George’s hospital. The spread of blaCTX-M-15 is probably due to horizontal gene transfer harbouring ISEcp1 and the conjugative properties of plasmids carrying blaCTX-M-15

Effect of Strain Profiling on Anisotropic Opto-Electronic Properties of As\u3csub\u3e2\u3c/sub\u3eX\u3csub\u3e3\u3c/sub\u3e (X =S, Te) Monolayers from First Principles

Strain Engineering is a widely adopted approach to modulate the opto-electronic performance of 2-Dimensional (2D) materials. Recently, anisotropic Van der Waals (vdW) based 2D As2S3 monolayer has gained significant attention within the scientific community due to its stability in ambient conditions. Similar compounds like As2Te3 have also been theoretically explored. However, its indirect bandgap nature limits its application in optical devices. In this study, a systematic study of compressive and tensile strain on three profiles–Uniaxial along a-axis, Uniaxial along b-axis and biaxial strain from −10% to +10%, is performed for As2S3 and As2Te3 monolayers. Certain strain profiles like Uniaxial tensile strain of 8% along b-axis results in transition to direct bandgap material. Similarly, for As2Te3, shear strain of (−10%, +8%) along (a, b) axis results in direct bandgap material. In addition, the anisotropic optical absorption spectrum is obtained for unstrained and strained monolayers within the random phase approximation (RPA)

Theoretical Investigations of the Structural, Dynamical, Electronic, Magnetic, and Thermoelectric Properties of Co\u3ci\u3eM\u3c/i\u3eRhSi (\u3ci\u3eM\u3c/i\u3e = Cr, Mn) Quaternary Heusler Alloys

The structural, dynamical, electrical, magnetic, and thermoelectric properties of CoMRhSi (M = Cr, Mn) quaternary Heusler alloys (QHAs) were investigated using density functional theory (DFT). The Y-type-II crystal structure was found to be the most stable configuration for these QHAs. Both CoCrRhSi and CoMnRhSi alloys possess a half-metallic behavior with a 100% spin-polarization as the majority spin channel is metallic. On the other hand, the minority spin channel is semiconducting with narrow indirect band gaps of 0.54 eV and 0.57 eV, respectively, along the Γ− high symmetry line. In addition, both CoCrRhSi and CoMnRhSi alloys possess a ferromagnetic structure with total magnetic moments of 4 μB, and 5 μB, respectively, which are prominent for spintronics applications. The thermoelectric properties of the subject QHAs were calculated by using Boltzmann transport theory within the constant relaxation time approximation. The lattice thermal conductivities were also evaluated by Slack’s equation. The predicted values of the figure-of-merit (ZT) for CoCrRhSi and CoMnRhSi were found to be 0.84 and 2.04 at 800 K, respectively, making them ideal candidates for thermoelectric applications

Liquid Metal Application for Continuously Tunable Frequency Reconfigurable Antenna

This paper presents two different designs for frequency reconfigurable antennas capable of continuous tuning. The radiator, for both antenna designs, is a microstrip patch, formed from liquid metal, contained within a microfluidic channel structure. Both patch designs are aperture fed. The microfluidic channel structures are made from polydimethylsiloxane (PDMS). The microfluidic channel structure for the first design has a meander layout and incorporates rows of posts. The simulated antenna provides a frequency tuning range of approximately 118% (i.e. 4.36 GHz) over the frequency range from 1.51 GHz to 5.87 GHz. An experimental result for the fully filled case shows a resonance at 1.49 GHz (1.3% error compared with the simulation). Experienced rheological behavior of the liquid metal necessitates microfluidic channel modifications. For that reason, we modified the channel structure used to realise the radiating patch for the second design. Straight channels are implemented in the second microfluidic device. According to simulation the design yields a frequency tuning range of about 77% (i.e. 3.28 GHz) from 2.62 GHz to 5.90 GHz

Complexity science for sleep stage classification from EEG

Automatic sleep stage classification is an important paradigm in computational intelligence and promises consider- able advantages to the health care. Most current automated methods require the multiple electroencephalogram (EEG) chan- nels and typically cannot distinguish the S1 sleep stage from EEG. The aim of this study is to revisit automatic sleep stage classification from EEGs using complexity science methods. The proposed method applies fuzzy entropy and permutation entropy as kernels of multi-scale entropy analysis. To account for sleep transition, the preceding and following 30 seconds of epoch data were used for analysis as well as the current epoch. Combining the entropy and spectral edge frequency features extracted from one EEG channel, a multi-class support vector machine (SVM) was able to classify 93.8% of 5 sleep stages for the SleepEDF database [expanded], with the sensitivity of S1 stage was 49.1%. Also, the Kappa’s coefficient yielded 0.90, which indicates almost perfect agreement

The prevalence of diabetes and prediabetes in the adult population of Jeddah, Saudi Arabia- a community-based survey

BACKGROUND: Type 2 (T2DM) is believed to be common in Saudi Arabia, but data are limited. In this population survey, we determined the prevalence of T2DM and prediabetes. MATERIALS AND METHODS: A representative sample among residents aged ≥ 18 years of the city of Jeddah was obtained comprising both Saudi and non-Saudi families (N = 1420). Data on dietary, clinical and socio-demographic characteristics were collected and anthropometric measurements taken. Fasting plasma glucose and glycated hemoglobin (HbA1c) were used to diagnose diabetes and prediabetes employing American Diabetes Association criteria. Multiple logistic regression analysis was used to identify factors associated with T2DM. RESULTS: Age and sex standardized prevalence of prediabetes was 9.0% (95% CI 7.5-10.5); 9.4% (7.1-11.8) in men and 8.6% (6.6-10.6) in women. For DM it was 12.1% (10.7-13.5); 12.9% (10.7-13.5) in men and 11.4% (9.5-13.3) in women. The prevalence based on World Population as standard was 18.3% for DM and 11.9% for prediabetes. The prevalence of DM and prediabetes increased with age. Of people aged ≥50 years 46% of men and 44% of women had DM. Prediabetes and DM were associated with various measures of adiposity. DM was also associated with and family history of dyslipidemia in women, cardiovascular disease in men, and with hypertension, dyslipidemia and family history of diabetes in both sexes. DISCUSSION: Age was the strongest predictor of DM and prediabetes followed by obesity. Of people aged 50 years or over almost half had DM and another 10-15% had prediabetes leaving only a small proportion of people in this age group with normoglycemia. Since we did not use an oral glucose tolerance test the true prevalence of DM and prediabetes is thus likely to be even higher than reported here. These results demonstrate the urgent need to develop primary prevention strategies for type 2 diabetes in Saudi Arabia