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Practical Protocol (practical + protocol)
Selected AbstractsBuchwald,Hartwig Aminations of Aryl Chlorides: A Practical Protocol Based on Commercially Available Pd(0)-NHC Catalysts.CHEMINFORM, Issue 28 2005L. J. Goossen Abstract For Abstract see ChemInform Abstract in Full Text. [source] A Simple and Practical Protocol for the Palladium-Catalyzed Cross-Coupling of Boronic Acids with Methyl Iodide.CHEMINFORM, Issue 8 2005Lukas J. Goossen No abstract is available for this article. [source] A practical protocol to assess impacts of unplanned disturbance: a case study in Tuggerah Lakes Estuary, NSWECOLOGICAL MANAGEMENT & RESTORATION, Issue 2003A. J. Underwood Summary Environmental managers are often confronted with unplanned or accidental disturbances that may lead to environmental impacts. Procedures for detecting or measuring the size of such impacts are complicated because of the lack of data available before the disturbance and because of the intrinsic variability of most natural measures. Here, a protocol for detecting impacts is illustrated for single-measure variables (numbers of individual species) and multivariate measures (relative abundances of invertebrates in assemblages). The present paper describes a case concerning drainage of acidified water into an estuary due to construction of a drainage channel in an area of wetland for which there had been no prior investigations (i.e. no ,before' data). The spatial extent of any impact was also unknowable. Sampling was, therefore, designed to allow for impacts of only a few tens of metres (using control sites 50 m from the mouth of the channel) and impacts covering much larger areas (500 m and 1 km from the mouth of the channel). Invertebrates in the mud around the channel and in control sites were sampled in replicated cores and the amount of seagrass in each core was weighed. Average abundances of invertebrate animals and weights of seagrass were compared, as was variation among samples in potentially impacted and control sites (using univariate analyses of variance). Sets of species were compared using multivariate methods to test the hypothesis that there was an impact at one of the scales examined. In fact, there was no evidence for any sort of impact on the fauna or seagrasses; the disturbance was a short-term pulse without any obvious or sustained ecological response. One consequence of the study was that the local council was able to demonstrate no impact requiring remediation and no penalties were imposed for the unapproved construction of the channel. The implications of this type of study after an environmental disturbance are discussed. The present study identifies the need for clear definition of relevant hypotheses, coupled with rigorous planning of sampling and analyses, so that reliable answers are available to regulators and managers. [source] An effective skeletal muscle prefractionation method to remove abundant structural proteins for optimized two-dimensional gel electrophoresisELECTROPHORESIS, Issue 11 2005Bradley Jarrold Abstract Proteomic analysis of biological samples in disease models or therapeutic intervention studies requires the ability to detect and identify biologically relevant proteins present in relatively low concentrations. The detection and analysis of these low-level proteins is hindered by the presence of a few proteins that are expressed in relatively high concentrations. In the case of muscle tissue, highly abundant structural proteins, such as actin, myosin, and tropomyosin, compromise the detection and analysis of more biologically relevant proteins. We have developed a practical protocol which exploits high-pH extraction to reduce or remove abundant structural proteins from skeletal muscle crude membrane preparations in a manner suitable for two dimensional gel electrophoresis. An initial whole-cell muscle lysate is generated by homogenization of powdered tissue in Tris-base. This lysate is subsequently partitioned into a supernatant and pellet containing the majority of structural proteins. Treatment of the pellet with high-pH conditions effectively releases structural proteins from membrane compartments which are then removed through ultracentrifugation. Mass spectrometric identification shows that the majority of protein spots reduced or removed by high-pH treatment were contractile proteins or contractile-related proteins. Removal of these proteins enabled successful detection and identification of minor proteins. Structural protein removal also results in significant improvement of gel quality and the ability to load higher amounts of total protein for the detection of lower abundant protein classes. [source] New efficient copper fluoride-based catalyst for enantioselective hydrosilylation of ketones in aerobic conditionsISRAEL JOURNAL OF CHEMISTRY, Issue 4 2001James Courmarcel A new copper(II) fluoride,chiral diphosphines catalytic system was developed. This one is very efficient and selective for the hydrosilylation of several substituted or unsubstituted aromatic ketones in so far as moderate to excellent enantioselectivities were obtained. An oxygen acceleration effect was observed that led us to propose a practical protocol with a low amount of catalyst. [source] Toward a practical protocol for human optic nerve DTI with EPI geometric distortion correctionJOURNAL OF MAGNETIC RESONANCE IMAGING, Issue 4 2009Udomchai Techavipoo PhD Abstract Purpose To develop a practical protocol for diffusion tensor imaging (DTI) of the human optic nerve with echo planar imaging (EPI) geometric distortion correction. Materials and Methods A conventional DTI protocol was modified to acquire images with fat and cerebrospinal fluid (CSF) suppression and field inhomogeneity maps of contiguous coronal slices covering the whole brain. The technique was applied to healthy volunteers and multiple sclerosis patients with and without a history of unilateral optic neuritis. DTI measures and optic nerve tractography before and after geometric distortion correction were compared. Diffusion measures from left and right or from affected and unaffected eyes in different subject cohorts were reported. Results The image geometry after correction closely resembled reference anatomical images. Optic nerve tractography became feasible after distortion correction. The diffusion measures from the healthy volunteers were in good agreement with the literature. Statistically significant differences were found in the fractional anisotropy and orthogonal eigenvalues between affected and unaffected eyes in optic neuritis patients with poor recovery. The diffusion measures before and after geometric distortion correction were not significantly different. For cohorts without optic neuritis, the difference between diffusion measures from left and right eyes was not statistically significant. Conclusion The proposed technique could provide a practical DTI protocol to study the human optic nerve. J. Magn. Reson. Imaging 2009;30:699,707. © 2009 Wiley-Liss, Inc. [source] Experimental quantum secret sharingFORTSCHRITTE DER PHYSIK/PROGRESS OF PHYSICS, Issue 8-10 2006Ch. Schmid Abstract We consider two simple and practical protocols for multiparty communication and show their experimental realization. These protocols deal with the task of secret sharing in which a secret message is split among several parties in a way that its reconstruction requires their mutual collaboration. In the presented schemes the parties solve the problem by two different approaches: The first uses as a resource the multiqubit entangled state |,4 - ,. As no interferometric setups are required here, contrary to known schemes, involving Greenberger-Horne-Zeilinger states, its implementation is simpler and more stable. In the second scheme only sequential transformations on a single qubit are used. This further tremendously simplifies the method, makes it scalable with regard to the number of participating partners and above all, technologically comparable to quantum key distribution. [source] Weight-related dosing, timing and monitoring hydrocortisone replacement therapy in patients with adrenal insufficiencyCLINICAL ENDOCRINOLOGY, Issue 3 2004Peak M. Mah Summary objective, The objective of this study was to examine the variables determining hydrocortisone (HC) disposition in patients with adrenal insufficiency and to develop practical protocols for individualized prescribing and monitoring of HC treatment. design and patients, Serum cortisol profiles were measured in 20 cortisol-insufficient patients (09·00 h cortisol < 50 nmol/l) given oral HC as either a fixed or ,body surface area-adjusted' dose in the fasted or fed state. Endogenous cortisol levels were measured in healthy subjects. Pharmacokinetic analysis was performed using P-Pharm software, and computer simulations were used to assess the likely population distribution of the data. results, Body weight was the most important predictor of HC clearance. A fixed 10-mg HC dose overexposed patients to cortisol by 6·3%, whereas weight-adjusted dosing decreased interpatient variability in maximum cortisol concentration from 31 to 7%, decreased area under the curve (AUC) from 50 to 22% (P < 0·05), and reduced overexposure to < 5%. Food taken before HC delayed its absorption. Serum cortisol measured 4 h after HC predicted cortisol AUC (r2 = 0·78; P < 0·001). conclusions, We recommend weight-adjusted HC dosing, thrice daily before food, monitored with a single serum cortisol measurement using a nomogram. This regimen was prospectively examined in 40 cortisol-insufficient patients, 85% of whom opted to remain on the new thrice-daily treatment regimen. [source] | ||||||||||||||||