93 research outputs found

    Simulations and Measurements of the Background Encountered by a High-Altitude Balloon-Borne Experiment for Hard X-ray Astronomy

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    We have modelled the hard X-ray background expected for a high-altitude balloon flight of the Energetic X-ray Telescope Experiment (EXITE2), an imaging phoswich detector/telescope for the 20--600 keV energy range. Photon and neutron-induced contributions to the background are considered. We describe the code and the results of a series of simulations with different shielding configurations. The simulated hard X-ray background for the actual flight configuration agrees reasonably well (within a factor of \sim 2) with the results measured on the first flight of EXITE2 from Palestine, Texas. The measured background flux at 100 keV is \sim 4 ×\times 104^{-4} counts cm2^{-2} s1^{-1} keV1^{-1}.Comment: 17 pages Latex (uses aaspp4.sty) plus 7 postscript figures: available in file figs.tar.g

    TILLING for allergen reduction and improvement of quality traits in peanut (Arachis hypogaea L.)

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    <p>Abstract</p> <p>Background</p> <p>Allergic reactions to peanuts (<it>Arachis hypogaea </it>L.) can cause severe symptoms and in some cases can be fatal, but avoidance is difficult due to the prevalence of peanut-derived products in processed foods. One strategy of reducing the allergenicity of peanuts is to alter or eliminate the allergenic proteins through mutagenesis. Other seed quality traits could be improved by altering biosynthetic enzyme activities. Targeting Induced Local Lesions in Genomes (TILLING), a reverse-genetics approach, was used to identify mutations affecting seed traits in peanut.</p> <p>Results</p> <p>Two similar copies of a major allergen gene, <it>Ara h 1</it>, have been identified in tetraploid peanut, one in each subgenome. The same situation has been shown for major allergen <it>Ara h 2</it>. Due to the challenge of discriminating between homeologous genes in allotetraploid peanut, nested PCR was employed, in which both gene copies were amplified using unlabeled primers. This was followed by a second PCR using gene-specific labeled primers, heteroduplex formation, CEL1 nuclease digestion, and electrophoretic detection of labeled fragments. Using ethyl methanesulfonate (EMS) as a mutagen, a mutation frequency of 1 SNP/967 kb (3,420 M<sub>2 </sub>individuals screened) was observed. The most significant mutations identified were a disrupted start codon in <it>Ara h 2.02 </it>and a premature stop codon in <it>Ara h 1.02</it>. Homozygous individuals were recovered in succeeding generations for each of these mutations, and elimination of Ara h 2.02 protein was confirmed. Several Ara h 1 protein isoforms were eliminated or reduced according to 2D gel analyses. TILLING also was used to identify mutations in fatty acid desaturase <it>AhFAD2 </it>(also present in two copies), a gene which controls the ratio of oleic to linoleic acid in the seed. A frameshift mutation was identified, resulting in truncation and inactivation of AhFAD2B protein. A mutation in <it>AhFAD2A </it>was predicted to restore function to the normally inactive enzyme.</p> <p>Conclusions</p> <p>This work represents the first steps toward the goal of creating a peanut cultivar with reduced allergenicity. TILLING in peanut can be extended to virtually any gene, and could be used to modify other traits such as nutritional properties of the seed, as shown in this study.</p

    Geology and taphonomy of a unique tyrannosaurid bonebed from the upper Campanian Kaiparowits Formation of southern Utah: implications for tyrannosaurid gregariousness

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    Tyrannosaurids are hypothesized to be gregarious, possibly parasocial carnivores engaging in cooperative hunting and extended parental care. A tyrannosaurid (cf. Teratophoneus curriei) bonebed in the late Campanian age Kaiparowits Formation of southern Utah, nicknamed the Rainbows and Unicorns Quarry (RUQ), provides the first opportunity to investigate possible tyrannosaurid gregariousness in a taxon unique to southern Laramidia. Analyses of the site’s sedimentology, fauna, flora, stable isotopes, rare earth elements (REE), charcoal content and taphonomy suggest a complex history starting with the deaths and transport of tyrannosaurids into a peri-fluvial, low-energy lacustrine setting. Isotopic and REE analyses of the fossil material yields a relatively homogeneous signature indicating the assemblage was derived from the same source and represents a fauna living in a single ecospace. Subsequent drying of the lake and fluctuating water tables simultaneously overprinted the bones with pedogenic carbonate and structurally weakened them through wet-dry cycling. Abundant charcoal recovered from the primary bone layer indicate a low temperature fire played a role in the site history, possibly triggering an avulsion that exhumed and reburied skeletal material on the margin of a new channel with minimal transport. Possible causes of mortality and concentration of the tyrannosaurids include cyanobacterial toxicosis, fire, and flooding, the latter being the preferred hypothesis. Comparisons of the RUQ site with other North American tyrannosaur bonebeds (Dry Island-Alberta; Daspletosaurus horneri-Montana) suggest all formed through similar processes. Combined with ichnological evidence, these tyrannosaur mass-burial sites could be part of an emerging pattern throughout Laramidia reflecting innate tyrannosaurid behavior such as habitual gregariousness

    Evaluation of the Physicochemical, Structural, Thermal, and Behavioral Properties of the Energy of Consciousness Healing Treated Zinc Chloride

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    Zinc chloride is a source of zinc used in various pharmaceutical/nutraceutical formulations. The objective of the current study was to investigate the impact of The Trivedi Effect® - Energy of Consciousness Healing Treatment (Biofield Energy Treatment) on physical, structural, thermal, and behavioral properties of zinc chloride using PXRD, PSD, FT-IR, UV-vis, and DSC analysis. Zinc chloride was divided into two parts – one part was control, while another part was treated with The Trivedi Effect® remotely by twenty renowned Biofield Energy Healers and defined as The Trivedi Effect® Treated sample. A significant alteration of the crystallite size and relative intensities of the PXRD peaks was observed in The Trivedi Effect® treated sample compared with the control sample. The average crystallite size of the treated sample was significantly increased by 23.18% compared with the control sample. The particle size values at d10, d50, and d90 values were significantly decreased by 3.70%, 4.13%, and 6.13%, respectively in the treated sample compared with the control sample. Therefore, the surface area of the treated sample was increased by 4.21% compared with the control sample. The FT-IR spectroscopic analysis revealed that Zn-Cl stretching in the control sample was found at 512 cm-1, whereas it was significantly shifted upward to 520 cm-1 in the treated sample. The UV-vis analysis exhibited that wavelength of the maximum absorbance (λmax) of the control and treated samples were at 197.6 nm and 197.1 nm, respectively. The DSC analysis exhibited that the melting temperature was decreased by 0.22%, while decomposition temperature was increased by 2.56% in the treated sample compared to the control sample. The latent heat of fusion of the treated sample (320.44 J/g) was significantly decreased by 16.70% compared with the control sample (284.67 J/g). Similarly, the enthalpy of decomposition of the treated sample (952.53 J/g) was significantly increased by 122.61% compared with the control sample (427.90 J/g). Thus, the results indicated that the thermal stability of the treated zinc chloride was improved compared with the control sample. The current study anticipated that The Trivedi Effect® - Energy of Consciousness Healing Treatment might lead to produce a thermally stable new polymorphic form of zinc chloride, which would be more soluble and bioavailable compared with the untreated compound. Hence, the treated zinc chloride would be very useful to design better nutraceutical/pharmaceutical formulations that might offer better therapeutic response against inflammatory diseases, immunological disorders, aging, stress, cancer, etc. https://www.trivedieffect.com/science/evaluation-of-the-physicochemical-structural-thermal-and-behavioral-properties-of-the-energy-of-consciousness-healing-treated-zinc-chloride http://www.sciencepublishinggroup.com/journal/paperinfo?journalid=217&doi=10.11648/j.bio.20170502.1

    Development of a High-Density Linkage Map and Tagging Leaf Spot Resistance in Pearl Millet Using Genotyping-by-Sequencing Markers

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    Pearl millet [Pennisetum glaucum (L.) R. Br; also Cenchrus americanus (L.) Morrone] is an important crop throughout the world but better genomic resources for this species are needed to facilitate crop improvement. Genome mapping studies are a prerequisite for tagging agronomically important traits. Genotyping-by-sequencing (GBS) markers can be used to build high-density linkage maps, even in species lacking a reference genome. A recombinant inbred line (RIL) mapping population was developed from a cross between the lines ‘Tift 99D2B1’ and ‘Tift 454’. DNA from 186 RILs, the parents, and the F1 was used for 96-plex ApeKI GBS library development, which was further used for sequencing. The sequencing results showed that the average number of good reads per individual was 2.2 million, the pass filter rate was 88%, and the CV was 43%. High-quality GBS markers were developed with stringent filtering on sequence data from 179 RILs. The reference genetic map developed using 150 RILs contained 16,650 single-nucleotide polymorphisms (SNPs) and 333,567 sequence tags spread across all seven chromosomes. The overall average density of SNP markers was 23.23 SNP/cM in the final map and 1.66 unique linkage bins per cM covering a total genetic distance of 716.7 cM. The linkage map was further validated for its utility by using it in mapping quantitative trait loci (QTLs) for flowering time and resistance to Pyricularia leaf spot [Pyricularia grisea (Cke.) Sacc.]. This map is the densest yet reported for this crop and will be a valuable resource for the pearl millet community

    Geoeconomic variations in epidemiology, ventilation management, and outcomes in invasively ventilated intensive care unit patients without acute respiratory distress syndrome: a pooled analysis of four observational studies

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    Background: Geoeconomic variations in epidemiology, the practice of ventilation, and outcome in invasively ventilated intensive care unit (ICU) patients without acute respiratory distress syndrome (ARDS) remain unexplored. In this analysis we aim to address these gaps using individual patient data of four large observational studies. Methods: In this pooled analysis we harmonised individual patient data from the ERICC, LUNG SAFE, PRoVENT, and PRoVENT-iMiC prospective observational studies, which were conducted from June, 2011, to December, 2018, in 534 ICUs in 54 countries. We used the 2016 World Bank classification to define two geoeconomic regions: middle-income countries (MICs) and high-income countries (HICs). ARDS was defined according to the Berlin criteria. Descriptive statistics were used to compare patients in MICs versus HICs. The primary outcome was the use of low tidal volume ventilation (LTVV) for the first 3 days of mechanical ventilation. Secondary outcomes were key ventilation parameters (tidal volume size, positive end-expiratory pressure, fraction of inspired oxygen, peak pressure, plateau pressure, driving pressure, and respiratory rate), patient characteristics, the risk for and actual development of acute respiratory distress syndrome after the first day of ventilation, duration of ventilation, ICU length of stay, and ICU mortality. Findings: Of the 7608 patients included in the original studies, this analysis included 3852 patients without ARDS, of whom 2345 were from MICs and 1507 were from HICs. Patients in MICs were younger, shorter and with a slightly lower body-mass index, more often had diabetes and active cancer, but less often chronic obstructive pulmonary disease and heart failure than patients from HICs. Sequential organ failure assessment scores were similar in MICs and HICs. Use of LTVV in MICs and HICs was comparable (42\ub74% vs 44\ub72%; absolute difference \u20131\ub769 [\u20139\ub758 to 6\ub711] p=0\ub767; data available in 3174 [82%] of 3852 patients). The median applied positive end expiratory pressure was lower in MICs than in HICs (5 [IQR 5\u20138] vs 6 [5\u20138] cm H2O; p=0\ub70011). ICU mortality was higher in MICs than in HICs (30\ub75% vs 19\ub79%; p=0\ub70004; adjusted effect 16\ub741% [95% CI 9\ub752\u201323\ub752]; p&lt;0\ub70001) and was inversely associated with gross domestic product (adjusted odds ratio for a US$10 000 increase per capita 0\ub780 [95% CI 0\ub775\u20130\ub786]; p&lt;0\ub70001). Interpretation: Despite similar disease severity and ventilation management, ICU mortality in patients without ARDS is higher in MICs than in HICs, with a strong association with country-level economic status. Funding: No funding
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