71,531 research outputs found

    The Davidon-Fletcher-Powell penalty function method: A generalized iterative technique for solving parameter optimization problems

    Get PDF
    The Fletcher-Powell version of the Davidon variable metric unconstrained minimization technique is described. Equations that have been used successfully with the Davidon-Fletcher-Powell penalty function technique for solving constrained minimization problems and the advantages and disadvantages of using them are discussed. The experience gained in the behavior of the method while iterating is also related

    Seed Germination in Ginkgo biloba L. I. Influences of Cold Treatment, Gibberellic Acid and Red Light

    Get PDF
    The influences of cold treatment, gibberellic acid and red light treatment on rate of germination of seeds of Ginkgo biloba L. were followed for a 12-wk period. Dispersal units were collected, and the outer fleshy layer was removed soon after harvest. Of water-imbibed, non-cold-treated seeds, 50% of those which germinated did so within 11 wk after planting. A single application of red light accelerated the 50% germination time by 3 wk. Imbibition in GA3 solution did not appear to accelerate germination. With 4-wk cold treatment the 50% germination time was accelerated 6 wk in water-imbibed seeds. Both red light and GA3 treated seeds also were accelerated 6 wk by cold treatment. An 8-wk cold treatment accelerated the 50% germination time 7 wk for all three treatment groups. The influence of red light observed on non-cold-treated seeds was not seen with seeds receiving a cold treatment prior to irradiation. A 12-wk cold treatment period delayed germination in all treated groups. Dry storage of seeds for 4mo at 25 C also delayed germination regardless of red light, GA3 or cold treatment

    Prebiotic, Probiotic, and Synbiotic Supplementation in Chronic Kidney Disease: A Systematic Review and Meta-analysis

    Get PDF
    Gut dysbiosis has been implicated in the pathogenesis of chronic kidney disease (CKD). Restoring gut microbiota with prebiotic, probiotic, and synbiotic supplementation has emerged as a potential therapeutic intervention but has not been systematically evaluated in the CKD population.This is a systematic review. A structured search of MEDLINE, CINAHL, EMBASE, Cochrane Central Register of Controlled Trials, and the International Clinical Trials Register Search Portal was conducted for articles published since inception until July 2017. Included studies were randomized controlled trials investigating the effects of prebiotic, probiotic, and/or synbiotic supplementation (>1\ua0week) on uremic toxins, microbiota profile, and clinical and patient-centered outcomes in adults and children with CKD.Sixteen studies investigating 645 adults met the inclusion criteria; 5 investigated prebiotics, 6 probiotics, and 5 synbiotics. The quality of the studies (Grades of Recommendation, Assessment, Development and Evaluation) ranged from moderate to very low. Prebiotic, probiotic, and synbiotic supplementation may have led to little or no difference in serum urea (9 studies, 345 participants: mean difference [MD] -0.30\ua0mmol/L, 95% confidence interval [CI] -2.20 to 1.61, P\ua0=\ua0.76, I\ua0=\ua053%), indoxyl sulfate (4 studies, 144 participants: MD -0.02\ua0mg/dL, 95% CI -0.09 to 0.05, P\ua0=\ua0.61, I\ua0=\ua00%), and p-cresyl sulfate (4 studies, 144 participants: MD -0.13\ua0mg/dL, 95% CI -0.41 to 0.15, P\ua0=\ua0.35, I\ua0=\ua00%). Prebiotic supplementation may have slightly reduced serum urea concentration (4 studies, 105 participants: MD -2.23\ua0mmol/L, 95% CI -3.83 to -0.64, P\ua0=\ua0.006, I\ua0=\ua011). Of the 2 studies investigating microbiota changes, synbiotic interventions significantly increased Bifidobacterium. Supplement effects on clinical outcomes were uncertain.There is limited evidence to support the use of prebiotics, probiotics, and/or synbiotics in CKD management

    Fattening Range Lambs on South Dakota Feeds

    Get PDF

    Thirteen-color narrow-band photometry of one thousand bright stars

    Get PDF
    Thirteen-color narrow-band photometry of one thousand bright star

    Preliminary design of a Primary Loop Pump Assembly (PLPA), using electromagnetic pumps

    Get PDF
    A preliminary design study of flight-type dc conduction-permanent magnetic, ac helical induction, and ac linear induction pumps for circulating 883 K (1130 F) NaK at 9.1 kg/sec (20 lb/sec) is described. Various electromagnetic pump geometrics are evaluated against hydraulic performance, and the effects of multiple windings and numbers of pumps per assembly on overall reliability were determined. The methods used in the electrical-hydraulic, stress, and thermal analysis are discussed, and the high temperature electrical materials selected for the application are listed

    One Health in food safety and security education: Subject matter outline for a curricular framework.

    Get PDF
    Educating students in the range of subjects encompassing food safety and security as approached from a One Health perspective requires consideration of a variety of different disciplines and the interrelationships among disciplines. The Western Institute for Food Safety and Security developed a subject matter outline to accompany a previously published One Health in food safety and security curricular framework. The subject matter covered in this outline encompasses a variety of topics and disciplines related to food safety and security including effects of food production on the environment. This subject matter outline should help guide curriculum development and education in One Health in food safety and security and provides useful information for educators, researchers, students, and public policy-makers facing the inherent challenges of maintaining and/or developing safe and secure food supplies without destroying Earth's natural resources

    Hypersonic test facility Patent

    Get PDF
    Hypersonic test facility for studying ablation in models under high pressure and high temperatur

    Scanning optical pyrometer for measuring temperatures in hollow cathodes

    Get PDF
    Life-limiting processes in hollow cathodes are determined largely by the temperature of the electron emitter. To support cathode life assessment, a noncontact temperature measurement technique which employs a stepper motor-driven fiber optic probe was developed. The probe is driven inside the hollow cathode and collects light radiated by the hot interior surface of the emitter. Ratio pyrometry is used to determine the axial temperature profile. Thermocouples on the orifice plate provide measurements of the external temperature during cathode operation and are used to calibrate the pyrometer system in situ with a small oven enclosing the externally heated cathode. The diagnostic method and initial measurements of the temperature distribution in a hollow cathode are discussed
    • …
    corecore