Mathematical modelling of gastric emptying and nutrient absorption in the human digestive system

Mathematical modelling of the digestive system can be achieved by assuming the digestive system is described as a series of ideal reactors. A well formulated model could give an understanding of how food products behave within the body, and offer some predictive possibility allowing the design of functional foods to have tailored nutritional responses. The models developed showed good estimates of the gastric emptying rates and glucose absorption rates for solutions with different viscosities and glucose concentrations, when a feedback mechanism is included. Implementing a population balance for solid breakdown in the stomach allowed for parameters to be linked to meal type. With parameter estimates from experimental gastric emptying of a solid meal being further validated against results for the same food type from different experimental results. The main outcomes of this work are (i) the inclusion of meals viscosity into models, and its effects on the gastric secretion and emptying rate as well as the mass transfer of nutrients in the intestinal lumen, (ii) the inclusion of a feedback mechanism on the rate of gastric emptying, and (iii) the development of a population balance to model solid breakdown within the stomach

Global discovery and characterization of small non-coding RNAs in marine microalgae

Background Marine phytoplankton are responsible for 50% of the CO2 that is fixed annually worldwide and contribute massively to other biogeochemical cycles in the oceans. Diatoms and coccolithophores play a significant role as the base of the marine food web and they sequester carbon due to their ability to form blooms and to biomineralise. To discover the presence and regulation of short non-coding RNAs (sRNAs) in these two important phytoplankton groups, we sequenced short RNA transcriptomes of two diatom species (Thalassiosira pseudonana, Fragilariopsis cylindrus) and validated them by Northern blots along with the coccolithophore Emiliania huxleyi. Results Despite an exhaustive search, we did not find canonical miRNAs in diatoms. The most prominent classes of sRNAs in diatoms were repeat-associated sRNAs and tRNA-derived sRNAs. The latter were also present in E. huxleyi. tRNA-derived sRNAs in diatoms were induced under important environmental stress conditions (iron and silicate limitation, oxidative stress, alkaline pH), and they were very abundant especially in the polar diatom F. cylindrus (20.7% of all sRNAs) even under optimal growth conditions. Conclusions This study provides first experimental evidence for the existence of short non-coding RNAs in marine microalgae. Our data suggest that canonical miRNAs are absent from diatoms. However, the group of tRNA-derived sRNAs seems to be very prominent in diatoms and coccolithophores and maybe used for acclimation to environmental conditions

Circulating microRNAs as biomarkers for acute ischemic stroke: a systematic review

Acute ischemic stroke is a leading cause of death and disability worldwide. Unlike myocardial infarction there is no current blood test to diagnose acute ischemic stroke. MicroRNAs are very stable in the blood and have been suggested as potential diagnostic markers. This review aimed to systematically assess case-control studies investigating the association of circulating microRNAs with acute ischemic stroke. Medline, CINAHL, Cochrane Library, Web of Science Scopus, and PubMed were searched for studies that examined the association of circulating microRNAs in acute ischemic stroke patients. Studies meeting specific inclusion and exclusion criteria (such as blood sample were obtained within 24 hours of an acute ischemic stroke) were selected for data extraction. Two authors extracted data from the included studies relevant to study design, patient characteristics, and relative microRNA expression. Eight studies were included involving 572 cases and 431 healthy controls. Twenty-two microRNAs (12 up-regulated and 10 downregulated) were reported as differentially expressed. Only one microRNA, miR-106b, was reported as differentially expressed in at least 2 studies. Significant heterogeneity in the design and methods of the included studies was noted. Differential expression of a large number of microRNAs has been reported early following acute ischemic stroke. More research is required in larger patient populations to further evaluate the diagnostic potential of the reported microRNAs

Atmospheric extinction coefficients in the Ic\mathrm{I_c} band for several major international observatories: Results from the BiSON telescopes, 1984 to 2016

Over 30 years of solar data have been acquired by the Birmingham Solar Oscillations Network (BiSON), an international network of telescopes used to study oscillations of the Sun. Five of the six BiSON telescopes are located at major observatories. The observational sites are, in order of increasing longitude: Mount Wilson (Hale) Observatory (MWO), California, USA; Las Campanas Observatory (LCO), Chile; Observatorio del Teide, Iza\~{n}a, Tenerife, Canary Islands; the South African Astronomical Observatory (SAAO), Sutherland, South Africa; Carnarvon, Western Australia; and the Paul Wild Observatory, Narrabri, New South Wales, Australia. The BiSON data may be used to measure atmospheric extinction coefficients in the $\mathrm{I_c}$ band (approximately 700-900 nm), and presented here are the derived atmospheric extinction coefficients from each site over the years 1984 to 2016.Comment: 15 pages, 10 figures, 4 tables. Accepted by Astronomical Journal: 2017 July 2

ARTP statement on cardiopulmonary exercise testing 2021.

Cardiopulmonary exercise testing (CPET) has become an invaluable tool in healthcare, improving the diagnosis of disease and the quality, efficacy, assessment and safety of treatment across a range of pathologies. CPET's superior ability to measure the global exercise response of the respiratory, cardiovascular and skeletal muscle systems simultaneously in a time and cost-efficient manner has led to the application of CPET in a range of settings from diagnosis of disease to preoperative assessment. The Association for Respiratory Technology and Physiology Statement on Cardiopulmonary Exercise Testing 2021 provides the practitioner and scientist with an outstanding resource to support and enhance practice, from equipment to testing to leadership, helping them deliver a quality assured service for the benefit of all patient groups

Cohort Study Examining the Association of Optimal Blood Pressure Control at Entry With Infrarenal Abdominal Aortic Aneurysm Growth

Background and Aim: The benefit of controlling cardiovascular risk factors in slowing the progression of small abdominal aortic aneurysm (AAA) is controversial. This study investigated the association of optimal blood pressure control at entry with the growth of small AAA. Methods and Results: A total of 1,293 patients with initial AAA diameter <50 mm were followed by a median 5 (inter-quartile range, IQR, 3–7) ultrasound scans for a median of 3.6 years (IQR 1.8, 5.3). Optimal blood pressure control was defined as blood pressure ≤140/90 mmHg at recruitment. The association of optimal blood pressure control at entry with AAA growth was assessed using linear mixed effects models adjusted for established risk factors of AAA growth and factors which were unequally distributed among the blood pressure groups. Optimal blood pressure control at entry was not significantly associated with AAA growth. In the risk factor adjusted model the mean difference in AAA growth between blood pressure groups was 0.04 mm/year (95% CI −0.20, 0.13; p = 0.65). The results were similar in sensitivity analyses excluding outliers or focused on systolic or diastolic blood pressure alone. Conclusions: This observational study suggests that optimal blood pressure control at entry is not associated with slower AAA growth