Predicting coexistence of plants subject to a tolerance-competition trade-off

Ecological trade-offs between species are often invoked to explain species coexistence in ecological communities. However, few mathematical models have been proposed for which coexistence conditions can be characterized explicitly in terms of a trade-off. Here we present a model of a plant community which allows such a characterization. In the model plant species compete for sites where each site has a fixed stress condition. Species differ both in stress tolerance and competitive ability. Stress tolerance is quantified as the fraction of sites with stress conditions low enough to allow establishment. Competitive ability is quantified as the propensity to win the competition for empty sites. We derive the deterministic, discrete-time dynamical system for the species abundances. We prove the conditions under which plant species can coexist in a stable equilibrium. We show that the coexistence conditions can be characterized graphically, clearly illustrating the trade-off between stress tolerance and competitive ability. We compare our model with a recently proposed, continuous-time dynamical system for a tolerance-fecundity trade-off in plant communities, and we show that this model is a special case of the continuous-time version of our model.Comment: To be published in Journal of Mathematical Biology. 30 pages, 5 figures, 5 appendice

A Prospective Randomized Controlled Trial to Study the Impact of a Nutrition-Sensitive Intervention on Adult Women With Cancer Cachexia Undergoing Palliative Care in India

Purpose. Advanced cancer patients with disease progression develop cachexia. Nevertheless, cancer patients at nutritional risk have shown improved body weight and quality of life with oral nutritional supplements. Method. This was a randomized controlled trial in adult female cancer patients (n = 63) attending palliative clinics, with symptoms of cachexia. Eligible patients were randomly distributed into control (n = 33) and intervention (n = 30) groups. Both groups were provided with nutritional and physical activity counseling, but the intervention group received an additional 100 g of Improved Atta (IAtta) for 6 months daily consumption. This study was designed to assess the efficacy of IAtta (with counseling) in enhancing the health status of cachexic patients. Anthropometric measurements, dietary intake, physical activity level and quality of life parameters were assessed at baseline, after 3 months, and at the end of 6 months. Results. Patients in the control group (n = 15) had significantly decreased body weight (P = .003), mid–upper-arm circumference (P = .002), and body fat (P = .002) by the end of intervention. A trend of body weight gain in the intervention group (n = 17; P = .08) and significant increase of body fat (P = .002) was observed; moreover, patients reported a significant improvement in fatigue (P = .002) and appetite scores (P = .006) under quality-of-life domains at the end of intervention. Conclusions. Embedding a nutrition-sensitive intervention ( IAtta ) within Indian palliative care therapy may improve quality of life and stabilize body weight in cancer cachexia patients

Optimization of water extract of Cinnamomum burmannii bark to ascertain its in vitro antidiabetic and antioxidant activities

The antidiabetic and antioxidant activity of water extract of Cinnamomum burmannii bark is well documented. This research aimed to optimize cinnamon water extraction process and verify active components instigating its in vitro antidiabetic activity. The study employed Design Expert 7.0 program to derive factorial design and optimization conditions. The extraction step comprised of three factors (temperature, concentration and time of extraction) and two levels (low and high), with four responses observed (yield, total phenolic content, IC50DPPH antioxidant activity, and IC50 α-glucosidase inhibition). The polynomial equations revealed influence and interaction among the selected factors to the responses and obtained overlay optimization of factors to responses. The results indicated that optimal temperature, concentration, and extraction time were 98 °C, 30% and 20 min, respectively. Corresponding DPPH, α-glucosidase, TPC, and yield values were 3.45 μg/ml, 0.50 μg/ml, 259.08 μg GAE/mg of sample, 6.28%, respectively. LCMS analysis of the optimum extract confirmed typical characteristic of C. burmanii contents (coumarins, polymers of proanthocyanidins A-type and protonated heterodimer of flavan-3-ol group). The optimized water extract of C.burmannii has the potency to assist in complementary therapy to modulate diabetes mellitus

Formulation and Characterization of Phytostanol Ester Solid Lipid Nanoparticles for the Management of Hypercholesterolemia: An ex vivo Study.

Background: Phytostanols are naturally occurring compounds that reduce blood cholesterol levels significantly. However, their aqueous insolubility poses formulation challenges. Aim: To formulate and characterize solid lipid nanoparticle carriers for phytostanol esters to enhance the bioavailability of phytostanols. Methods: Phytostanol ester solid lipid nanoparticles were formulated by the microemulsion method. They were characterized for particle size distribution, polydispersity index, shape, surface charge, entrapment efficiency, stability, chemical structure, and thermal properties. The uptake of the formulation by cell lines, HepG2 and HT-29, and its effect on cell viability were evaluated. Results: The formulation of solid lipid nanoparticles was successfully optimised by varying the type of lipids and their concentration relative to that of surfactants in the present study. The optimised formulation had an average diameter of (171 ± 9) nm, a negative surface charge of (− 23.0 ± 0.8) mV and was generally spherical in shape. We report high levels of drug entrapment at (89 ± 5)% in amorphous form, drug loading of (9.1 ± 0.5)%, nanoparticle yield of (67 ± 4)% and drug excipient compatibility. The biological safety and uptake of the formulations were demonstrated on hepatic and intestinal cell lines. Conclusion: Phytostanol ester solid lipid nanoparticles were successfully formulated and characterized. The formulation has the potential to provide an innovative drug delivery system for phytostanols which reduce cholesterol and have a potentially ideal safety profile. This can contribute to better management of one of the main risk factors of cardiovascular disease

Influence of sulphide Cu (I) promoting additives concentration on acid and catalytic properties of high-silica zeolites in straight-run gasoline conversion

In present article the influence of Cu[2]S promoting additives concentration on acid and catalytic properties of high silica MFI-type zeolites is investigated in the process of conversion of straight-run gasoline fractions of gas condensate into high octane components of motor fuels. It was shown that zeolite modified with 1% of Cu[2]S nanoscaled powder possesses the highest acid centers concentration and highest catalytic activity

Attitudinal Determinants of diet and lifestyle among African and Caribbean women living in the UK : study design and rationale

The aim of this article is to describe the rationale and design of a cross-sectional study that investigated the influence of attitudinal factors on diet and lifestyle of African and Caribbean women living in the UK. The results of the study will be presented elsewhere. African and Caribbean women are at high risk of obesity which exacerbates health inequalities. In the UK, little work has been carried out to better understand attitudinal factors that contribute towards obesity, lifestyle and health practice amongst this group. Methods: The study applied a comprehensive questionnaire to capture socio-demographic data and explore general attitudes towards diet and lifestyle of African and Caribbean women. Dietary data were collected using triple-pass 24-hour recalls. In addition, all participants had anthropometric measures, blood pressure and biochemical indices assessed using standardised methods. Discussion: Potential strengths and limitations of the current study design, exploring health, diet, and lifestyle habits and the contextual influence on these practices among African and Caribbean in the UK are discussed. Findings from this study will contribute to the understanding of food and health practices, the role of socio-cultural factors and potential barriers and facilitators to the adoption of a healthy lifestyle, which could reduce the risk of cardiovascular disease, obesity, and type 2 diabetes, all of which have increased prevalence in these communities

Risk Factors for Maternal Vitamin D Deficiency within the United Arab Emirates

Introduction: Vitamin D deficiency during pregnancy is a public health problem and it has been associated with negative pregnancy outcomes for both mothers and infants. Aim: To estimate the prevalence of vitamin D deficiency in pregnant women in the United Arab Emirates (UAE) and to identify the contribution of risk factors to the 25(OH)D levels. Methods: It is a cross-sectional study in which vitamin D levels of 1088 adult pregnant women were assessed. Information on vitamin D intake was available in a sub-sample of 266 women. Results: The mean serum 25(OH)D was 26.2 nmol/L (95% CI 25.2-27.1 range 5-129.1 nmol/L) with 69% of women being vitamin D deficient (<30 nmol/L). In the bivariate analysis, showed that no predictors could have been indicated as no values exceeded significance (p<0.2). Stepwise multiple linear regression analysis could not be applied to identify predictors of vitamin D levels as no values exceeded p=0.2. Conclusion: Due to the high prevalence of vitamin deficiency in UAE, there is an urge for interventions focusing on supplementation, fortification and diet diversity for preventing health consequences during a critical period of development

Re-formulating Monascus fermented durian seeds yogurt with strawberry (Fragaria x ananassa) puree to enhance its microbiological, physicochemical and organoleptic properties

Healthy lifestyle and consumption of fermented products, is the trend that is popular among health-conscious individuals. Monascus fermented durian seed (MFDS) is a fermented product of durian seed using the Monascus purpureus culture. Even though MFDS possessed specific bioactive properties, such as competent antioxidant, antidiabetes and anti-hypercholesterolemia. However, the addition of MFDS extract to yogurt has some limitations [e.g.: reduction of colour and taste preference]. Thus, there is a need for an innovative food technology method to enhance key organoleptic characteristics of a newly formulated yogurt product made of MFDS and strawberry puree. The aim of this investigation was to determine the effect of difference concentrations of strawberry puree on microbiology, physicochemical, and organoleptic properties of MFDS yogurt product. The results showed that all concentrations of strawberry puree [5%, 10%, 15%, and 20% (w/v) of the total mixture] have affected the microbial, physicochemical and sensory properties of re-formulated yogurt product. Strawberry purees caused an acidity increase of yogurt with pH value between 4.287 and 4.475. The recorded titratable acidity was 0.74% to 1.17%. The colour parameters such as lightness and yellowness also decreased, however, the values of redness, chroma, and hue increased. The shelf-life experiment (maximum of 7 days) of the re-formulated yogurt revealed a maximum syneresis of 22.52%. Based on the sensory evaluation preferences, re-formulated yogurt with 10% strawberry puree was the most favourable product, with a preferred value of the colour at 5.6 (rather like), the flavour at 5.8 (rather like), and mouthfeel (rather like)