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141.
Abdul J Chaudhary Spencer O
V Dando Susan M Grimes 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》2001,76(1):47-52
The fluidised bed cell of inert glass beads is an electrolytic reactor which is designed to provide higher ion‐transfer conditions during electrolysis, thus enabling metals to be removed efficiently from dilute solutions. The effectiveness of the method as a means of removing metals from effluent to meet discharge consent levels is studied for the in situ removal of tin from dilute solution (concentration range 0.25–1.00 gdm−3). The results show that the combination of high mass transport conditions and a moderately high electrode surface area per unit electrode volume provides a system for continuous removal of metal from dilute solutions. The effects of acid concentration, tin concentration, current density, fluidised bed agitation, electrode spacing, type of electrode and lead impurities on the removal of tin are reported and expressed in terms of the percentage removal of tin (αSn), the efficiency of tin deposition (ϕSn), and the energy consumption (WSn) for 1 kg of tin deposited. The results show that tin can, under optimised conditions, be removed from dilute solutions to a residual concentration of 0.001 gdm−3. © 2001 Society of Chemical Industry 相似文献
142.
ABSTRACT: BACKGROUND: Weight loss is often difficult to achieve in individuals with type 2 diabetes and anti-obesity drugs are often advocated to support dietary intervention. Despite the extensive use of centrally acting anti-obesity drugs, there is little evidence of how they affect dietary composition. We investigated changes in energy intake and dietary composition of macro- and micronutrients following therapy with the endocannabinoid receptor blocker, rimonabant. METHODS: 20 obese patients with type 2 diabetes were studied before and after 6 months dietary intervention with rimonabant. Dietary intervention was supervised by a diabetes dietician. Five-day food diaries were completed at baseline and at 6 months and dietary analysis was performed using computer software (Dietplan 6). RESULTS: After 6 months, (compared with baseline) there were reductions in weight (107+/-21Kg versus 112+/-21, p<0.001, 4% body weight reduction), and improvements in HbA1c (7.4+/-1.7 versus 8.0+/-1.6%, p<0.05) and HDL cholesterol. Intake of energy (1589+/-384 versus 2225+/-1109kcal, p<0.01), carbohydrate (199+/-74 versus 273+/-194g, p<0.05), protein (78+/-23 versus 98+/-36g, p<0.05), fats (55+/-18 versus 84+/-39g, p<0.01) and several micronutrients were reduced. However, relative macronutrient composition of the diet was unchanged. Improvement in blood glucose was strongly correlated with a reduction in carbohydrate intake (r = 0.76, p<0.001). CONCLUSIONS: In obese patients with type 2 diabetes, rimonabant in combination with dietary intervention led to reduced intake of energy and most macronutrients. Despite this, macronutrient composition of the diet was unaltered. These dietary changes (especially carbohydrate restriction) were associated with weight loss and favourable metabolic effects. 相似文献
143.
Abdolmohammadi S Siyamak S Ibrahim NA Yunus WM Rahman MZ Azizi S Fatehi A 《International journal of molecular sciences》2012,13(4):4508-4522
This study investigates the effects of calcium carbonate (CaCO(3)) nanoparticles on the mechanical and thermal properties and surface morphology of polycaprolactone (PCL)/chitosan nanocomposites. The nanocomposites of PCL/chitosan/CaCO(3) were prepared using a melt blending technique. Transmission electron microscopy (TEM) results indicate the average size of nanoparticles to be approximately 62 nm. Tensile measurement results show an increase in the tensile modulus with CaCO(3) nanoparticle loading. Tensile strength and elongation at break show gradual improvement with the addition of up to 1 wt% of nano-sized CaCO(3). Decreasing performance of these properties is observed for loading of more than 1 wt% of nano-sized CaCO(3). The thermal stability was best enhanced at 1 wt% of CaCO(3) nanoparticle loading. The fractured surface morphology of the PCL/chitosan blend becomes more stretched and homogeneous in PCL/chitosan/CaCO(3) nanocomposite. TEM micrograph displays good dispersion of CaCO(3) at lower nanoparticle loading within the matrix. 相似文献
144.
Soini HA Linville SU Wiesler D Posto AL Williams DR Novotny MV 《Journal of chemical ecology》2012,38(2):145-156
We investigated head- and cheek-rubbing behavior in four species of large felines, lions (Leo panther), leopards (Panthera pardus), tigers (Panthera tigris), and cougars (Puma concolor), in captivity. Preliminary behavioral observations found that lions and tigers, but not leopards and cougars, showed behavioral
responses to cardboard rubbing samples from head and cheek areas from conspecific felines, compared to the blank cardboard
controls. In this context, surface samples on the facial areas of each species were collected to analyze volatile organic
compounds that could be involved in the facial marking of felines. Previously developed stir bar surface sampling methodology
was used. From all cheek and forehead samples, 100 volatile organic compounds were identified or tentatively identified. Among
these, 41 have been previously reported to be present in feline urine and marking secretions. Several new compounds were identified
on facial surfaces. Some of the compounds showed substantial quantitative differences among the species. One compound, that
has not been reported previously in mammals, 3-acetamidofuran, was found in all investigated species. It was synthesized and
tested for behavioral responses. No responses were elicited in a preliminary test. Future research will test other potential
signaling compounds and their mixtures for ability to elicit behavioral responses. 相似文献
145.
This article develops practical methods for Bayesian inference in the autoregressive fractionally integrated moving average (ARFIMA) model using the exact likelihood function, any proper prior distribution, and time series that may have thousands of observations. These methods utilize sequentially adaptive Bayesian learning, a sequential Monte Carlo algorithm that can exploit massively parallel desktop computing with graphics processing units (GPUs). The article identifies and solves several problems in the computation of the likelihood function that apparently have not been addressed in the literature. Four applications illustrate the utility of the approach. The most ambitious is an ARFIMA(2,d,2) model for the Campito tree ring time series (length 5405), for which the methods developed in the article provide an essentially uncorrelated sample of size 16,384 from the exact posterior distribution in under four hours. Less ambitious applications take as little as 4 minutes without exploiting GPUs. 相似文献
146.
147.
Susan Schonfield Peter Frost Robert Cramb Chris Royle 《Journal of Automated Methods and Management in Chemistry》1989,11(1):22-27
The Nova Stat Profile 1 analyser, a combined sodium, potassium,
ionized calcium, haematocrit and conventional blood gas analyser,
was evaluated over a four month period. In addition to assessing
and demonstrating that the instrument met analytical requirements,
an appreciation of the use of ionised calcium (iCa) was made.
Prospective costs were characterised and practical problems of iCa
measurement addressed. 相似文献
148.
David B. Whitman Christopher D. Cox Dr. Michael J. Breslin Karen M. Brashear John D. Schreier Michael J. Bogusky Dr. Rodney A. Bednar Dr. Wei Lemaire Joseph G. Bruno George D. Hartman Dr. Duane R. Reiss C. Meacham Harrell Richard L. Kraus Dr. Yuxing Li Susan L. Garson Scott M. Doran Dr. Thomayant Prueksaritanont Dr. Chunze Li Dr. Christopher J. Winrow Dr. Kenneth S. Koblan Dr. John J. Renger Paul J. Coleman Dr. 《ChemMedChem》2009,4(7):1069-1074
Silent Night : Antagonism of the orexin (or hypocretin) system has recently been identified as a novel mechanism for the treatment of insomnia. Herein, we describe discovery of a dual (OX1R/OX2R) orexin receptor antagonist featuring a 1,4‐diazepane central constraint that blocks orexin signaling in vivo. In telemetry‐implanted rats, oral administration of this antagonist produced a decrease in wakefulness, while increasing REM and non‐REM sleep.
149.
Alexander Semmler Susanna Moskau Andreas Grigull Susan Farmand Thomas Klockgether Yvo Smulders Henk Blom Bernd Zur Birgit Stoffel-Wagner Michael Linnebank 《Nutrition journal》2010,9(1):1-4
Background
Several studies demonstrated an association of homocysteine plasma levels and the plasma lipoprotein profile. This cross-sectional pilot study aimed at analyzing whether blood levels of the two important cofactors of homocysteine metabolism, folate and vitamin B12, coincide with the lipoprotein profile.Methods
In a retrospective single center approach, we analyzed the laboratory database (2003-2006) of the University Hospital Bonn, Germany, including 1743 individuals, in whom vitamin B12, folate and at least one lipoprotein parameter had been determined by linear multilogistic regression.Results
Higher folate serum levels were associated with lower serum levels of low density lipoprotein cholesterol (LDL-C; Beta = -0.164; p < 0.001), higher levels of high density lipoprotein cholesterol (HDL-C; Beta = 0.094; p = 0.021 for trend) and a lower LDL-C-C/HDL-C-ratio (Beta = -0.210; p < 0.001). Using ANOVA, we additionally compared the individuals of the highest with those of the lowest quartile of folate. Individuals of the highest folate quartile had higher levels of HDL-C (1.42 ± 0.44 mmol/l vs. 1.26 ± 0.47 mmol/l; p = 0.005), lower levels of LDL-C (3.21 ± 1.04 mmol/l vs. 3.67 ± 1.10 mmol/l; p = 0.001) and a lower LDL-C/HDL-C- ratio (2.47 ± 1.18 vs. 3.77 ± 5.29; p = 0.002). Vitamin B12 was not associated with the lipoprotein profile.Conclusion
In our study sample, high folate levels were associated with a favorable lipoprotein profile. A reconfirmation of these results in a different study population with a well defined status of health, diet and medication is warranted. 相似文献150.
Richard B Kreider Colin D Wilborn Lem Taylor Bill Campbell Anthony L Almada Rick Collins Mathew Cooke Conrad P Earnest Mike Greenwood Douglas S Kalman Chad M Kerksick Susan M Kleiner Brian Leutholtz Hector Lopez Lonnie M Lowery Ron Mendel Abbie Smith Marie Spano Robert Wildman Darryn S Willoughby Tim N Ziegenfuss Jose Antonio 《Journal of the International Society of Sports Nutrition》2010,7(1):1-43
Sports nutrition is a constantly evolving field with hundreds of research papers published annually. For this reason, keeping up to date with the literature is often difficult. This paper is a five year update of the sports nutrition review article published as the lead paper to launch the JISSN in 2004 and presents a well-referenced overview of the current state of the science related to how to optimize training and athletic performance through nutrition. More specifically, this paper provides an overview of: 1.) The definitional category of ergogenic aids and dietary supplements; 2.) How dietary supplements are legally regulated; 3.) How to evaluate the scientific merit of nutritional supplements; 4.) General nutritional strategies to optimize performance and enhance recovery; and, 5.) An overview of our current understanding of the ergogenic value of nutrition and dietary supplementation in regards to weight gain, weight loss, and performance enhancement. Our hope is that ISSN members and individuals interested in sports nutrition find this review useful in their daily practice and consultation with their clients. 相似文献