Hepcidin: A Critical Regulator of Iron Metabolism during Hypoxia

Iron status affects cognitive and physical performance in humans. Recent evidence indicates that iron balance is a tightly regulated process affected by a series of factors other than diet, to include hypoxia. Hypoxia has profound effects on iron absorption and results in increased iron acquisition and erythropoiesis when humans move from sea level to altitude. The effects of hypoxia on iron balance have been attributed to hepcidin, a central regulator of iron homeostasis. This paper will focus on the molecular mechanisms by which hypoxia affects hepcidin expression, to include a review of the hypoxia inducible factor (HIF)/hypoxia response element (HRE) system, as well as recent evidence indicating that localized adipose hypoxia due to obesity may affect hepcidin signaling and organismal iron metabolism

Concentration and Ratio of Essential Fatty Acids Influences the Inflammatory Response in Lipopolysaccharide Challenged Mice

The goal of this study was to evaluate the role of both the % of dietary, 18-carbon PUFA (2.5%, 5% and 10%) and the n-6:n-3 ratio (1:1, 10:1 and 20:1) on the acute inflammatory response. Mice were fed diets for 8 weeks and injected intraperitoneally with LPS to induce acute inflammation. After 24. h mice were sacrificed and plasma cytokines measured. Diets significantly affected the erythrocyte PUFA composition and the effect of PUFA ratio was more prominent than of PUFA concentration. The % dietary PUFA affected feed efficiency (

Trash-to-Gas: Converting Space Trash into Useful Products

NASA's Logistical Reduction and Repurposing (LRR) project is a collaborative effort in which NASA is determined to reduce total logistical mass through reduction, reuse and recycling of various wastes and components of long duration space missions and habitats. LRR is focusing on four distinct advanced areas of study: Advanced Clothing System, Logistics-to-Living, Heat Melt Compactor and Trash to Supply Gas (TtSG). The objective of TtSG is to develop technologies that convert material waste, human waste and food waste into high-value products. High-value products include life support oxygen and water, rocket fuels, raw material production feedstocks, and other energy sources. There are multiple pathways for converting waste to products involving single or multi-step processes. This paper discusses thermal oxidation methods of converting waste to methane. Different wastes, including food, food packaging, Maximum Absorbent Garments (MAGs), human waste simulants, and cotton washcloths have been evaluated in a thermal degradation reactor under conditions promoting pyrolysis, gasification or incineration. The goal was to evaluate the degradation processes at varying temperatures and ramp cycles and to maximize production of desirable products and minimize high molecular weight hydrocarbon (tar) production. Catalytic cracking was also evaluated to minimize tar production. The quantities of CO2, CO, CH4, and H2O were measured under the different thermal degradation conditions. The conversion efficiencies of these products were used to determine the best methods for producing desired products

A geotechnical Study on the Characteristics of Swell-Shrink Soils in Kibaha, Tanzania

The properties of Swell-shrink of the soils in Kibaha were studied. Geotechnical and mineralogical tests were carried out on disturbed and undisturbed samples recovered from trial pits at different locations. Using empirical relationships, the swelling potential of the soil was established in correlation with the soil plasticity limits and grain size analysis (claycontents). The average values for the plastic, liquid and linear shrinkage limits for soils were 22.2%, 60.7% and 14.5% respectively. The plasticity Index (PI) which is the difference between liquid limits and plastic limits ranges from 27% to 47.4% with an average of 38.5%. The natural water content is very small ranging from 7% to 11% with an average of9.6% which is smaller than the corresponding shrinkage limit. Furthermore, the samples were tested for percentage of volume change in free swell tests and swelling pressure in one-dimensional swell tests. The free swell and upward pressure were in the excess of 100% to 150% and 50 kPa respectively. In addition, the coefficient of linear extensibility ranged from 0.09 to 0.14 signifying high to very high swell-shrink potential. Finally, the main clay mineral present in the sample was determined by running the X-ray diffraction (XRD) test. The x-ray diffraction scan indicated the presence of high proportion of clay minerals (smectite) in the soils

ASEA Redox Supplement Fails to Improve Aerobic Capacity and Ventilatory Threshold: A Double-Blind, Placebo-Controlled Study

The ASEA redox cell signaling supplement beverage has been commercially available for the past decade. Despite the market longevity of this supplement, athletic sponsorship, and anecdotal ergogenic claims, there is no independent, peer-reviewed research on its efficacy. The purpose of this study was to determine if ASEA improves aerobic capacity (VO2 max) and/or ventilatory threshold (VT) of physically active subjects. Eleven (6 females, 5 males) young adults (21.9 ± 3.9 yrs) performed 3 VO2 max tests: (a) baseline; (b) after 2 wks of supplementing with ASEA; and (c) after 2 wks of taking a placebo in a cross-over design. The treatment order was randomized and double-blind. The subjects consumed 4 oz∙d-1 (118 mL∙d -1) of the ASEA treatment according to the manufacturer’s recommendations. The subjects’ VO2 max values at baseline (55.0 ± 8.6 mL·kg-1 ·min-1), placebo (53.6 ± 9.1 mL·kg-1 ·min-1), and ASEA (53.7 ± 10.1 mL·kg-1 ·min-1) were not significantly different (P=0.172). Similarly, absolute VO2 max (P=0.436), time to reach VO2 max (P=0.955), VT as a percentage of VO2 max (P=0.678), and maximal heart rate (P=0.410) were not significantly different between trials. Contrary to the manufacturer’s claims, ASEA did not improve the aerobic performance of young, fit adults who supplemented with the product daily for 2 wks

Food Matrix and the Microbiome: Considerations for Preclinical Chronic Disease Studies

Animal models of chronic disease are continuously being refined and have evolved with the goal of increasing the translation of results to human populations. Examples of this progress include transgenic models and germ-free animals conventionalized with human microbiota. The gut microbiome is involved in the etiology of several chronic diseases. Therefore, consideration of the experimental conditions that may affect the gut microbiome in preclinical disease is very important. Of note, diet plays a large role in shaping the gut microbiome and can be a source of variation between animal models and human populations. Traditionally, nutrition researchers have focused on manipulating the macronutrient profile of experimental diets to model diseases such as metabolic syndrome. However, other dietary components found in human foods, but not in animal diets, can have sizable effects on the composition and metabolic capacity of the gut microbiome and, as a consequence, manifestation of the chronic disease being modeled. The purpose of this review is to describe how food matrix food components, including diverse fiber sources, oxidation products from cooking, and dietary fat emulsifiers, shape the composition of the gut microbiome and influence gut health

Waste Water Brine Purification through Electrodialysis Ion Exchange

Reutilizing resources onboard the International Space Station (ISS) and for future deep space missions are critical for mission longevity and sustainability. Waste water brine produced from water recovery systems contain chemical species that could be processed into a potential fertilizer for future plant systems.Fertilizer production can be achieved through a process called electrodialysis ion exchange. Waste water containing inorganic salt components are fed through a series of ion exchange membranes to produce fertilizer (a phosphate rich stream), electrolysis-grade water, and other useful commodities.A test bed was constructed to conduct controlled experiments and an experimental design procedure developed to determine the feasibility of the process. Conductivity and pH probes were utilized to determine the ion concentration in each of the product streams, along with ion chromatography (IC) to define the exact concentration of each ion in every stream throughout the experiment. This is crucial in order to convey the effectiveness of ion removal from the incoming waste water stream.The waste water and electrolyte streams were prepared in the lab prior to experimentation. Additionally, the ion exchange membrane configurations were developed and Opto 22 data analysis software incorporated to conduct measurements in real time.Ions successfully diffused across their respective membranes into the concentrate, acid, and base streams. This resulted in pure water, a phosphate rich stream, and a separate anion/hydrogen and cation/hydroxide stream

Scaling metagenome sequence assembly with probabilistic de Bruijn graphs

Deep sequencing has enabled the investigation of a wide range of environmental microbial ecosystems, but the high memory requirements for {\em de novo} assembly of short-read shotgun sequencing data from these complex populations are an increasingly large practical barrier. Here we introduce a memory-efficient graph representation with which we can analyze the k-mer connectivity of metagenomic samples. The graph representation is based on a probabilistic data structure, a Bloom filter, that allows us to efficiently store assembly graphs in as little as 4 bits per k-mer, albeit inexactly. We show that this data structure accurately represents DNA assembly graphs in low memory. We apply this data structure to the problem of partitioning assembly graphs into components as a prelude to assembly, and show that this reduces the overall memory requirements for {\em de novo} assembly of metagenomes. On one soil metagenome assembly, this approach achieves a nearly 40-fold decrease in the maximum memory requirements for assembly. This probabilistic graph representation is a significant theoretical advance in storing assembly graphs and also yields immediate leverage on metagenomic assembly