Home About us Contact
|
Home About us Contact | ||
|
|
||
Various Techniques (various + techniques)
Selected AbstractsCT02 A STUDY TO EVALUATE VARIOUS TECHNIQUES OF CORONARY ARTERY BYPASS GRAFTINGANZ JOURNAL OF SURGERY, Issue 2007P. Singhal Introduction In Wellington Hospital, CABG is being performed by various techniques like OPCAB, On-pump cardioplegic arrest, fibrillatory arrest and On-pump beating heart. Aim This study was undertaken to compare morbidity and mortality between On- pump CABG and OPCAB on basis of Euroscore. Material and Method From January 2003 till December 2004, data were collected according to Australasian society of Cardiothoracic surgery data set. Euroscores were calculated and patients were divided into 3 groups. Results of OPCAB and On-pump CABG were compared on basis of Euroscore group. In this period we performed 350 On-pump CABG and 254 OPCAB. Results OPCAB group had less number of grafts per patients. Even for triple vessel disease numbers of grafts were lower in OPCAB group. OPCAB group had more patients with total arterial revascularization. There were 10 deaths in On-pump group and 1 in OPCAB group. In the low and moderate risk group there was no significant difference in hospital stay, ventilation hours and ICU stay. However inotropic requirement and requirements of blood products were less in OPCAB group. There was no statistically significant difference between Incidence of new renal failure or arrhythmia in two groups. 2 patients in each group had blocked graft in immediate postop period and required revascularization. There were only 5 patients in the high-risk group in OPCAB making intergroup comparisons difficult. Conclusion OPCAB does not offer any significant advantage in terms of mortality and morbidity over On-pump CABG. To evaluate the effects of number of grafts and total arterial revascularization, it needs a long-term follow-up. [source] A Method of Augmenting the Cheek Area Through SMAS, subSMAS, and Subcutaneous Tissue Recruitment During Facelift SurgeryDERMATOLOGIC SURGERY, Issue 3 2003Dominic A. Brandy MD BACKGROUND As the human face ages, there is a depletion of fat that occurs in the submalar region. Various techniques such as fat transfers, fillers, alloplastic implants, and composite rhytidectomies have been used to augment this area in the past. OBJECTIVE To describe a technique that augments the submalar areas during facelift surgery without the use of fat transfer, fillers, alloplastic implants, or a risky composite technique. METHOD An oval is scribed over the depressed submalar areas preoperatively. During facelift surgery, a fusiform area is scribed over the SMAS. This fusiform is scribed so that the medial end is directed at the center of the submalar depression, and the lateral end is toward the posterior earlobe. A defect is created within the lateral aspect of the fusiform, but not the medial portion. The fusiform is subsequently closed with a 2-0 Ethibond suture using three horizontal mattress sutures and two interrupted sutures. Upon closure of this defect, SMAS, subSMAS, and subcutaneous tissue overlying the SMAS are recruited into the submalar defect by the simple phenomenon of dog-ear formation. Additionally, there is a component of frank elevation of the tissues inferior to the medial aspect of the fusiform and submalar space. RESULTS The aforementioned technique has been performed on 123 patients over 7 years and has resulted in consistently good improvement in the submalar space. The procedure is not difficult to learn, and good results can be achieved with initial cases. The learning curve was not found to be steep, with good results being achieved quickly. CONCLUSION Depression of the submalar space plays a significant role in creating an aged face. In the past, various fillers and/or alloplastic implants have been used to augment this region. A low-risk method is described that mobilizes SMAS, subSMAS, and subcutaneous tissues into the submalar space through the phenomenon of dog-ear formation after fusiform closure. [source] Titanium Containing ,-MnO2 (TM) Hollow Spheres: One-Step Synthesis and Catalytic Activities in Li/Air Batteries and Oxidative Chemical ReactionsADVANCED FUNCTIONAL MATERIALS, Issue 19 2010Lei Jin Abstract Titanium containing ,-MnO2 octahedral molecular sieves having hollow sphere structures are successfully prepared for the first time using a one-step synthesis method. Titanium cations are used as structure-directing agents in the synthesis process. The assembly of the hollow spheres is carried out at the beginning of the process. Various techniques including XRD, N2 adsorption, SEM, EDX, RAMAN, TEM, XPS, and TGA are employed for the materials characterization. Ti is incorporated into the MnO2 framework in isolated sites, and TiO2 phases (anatase and rutile) are not observed. When introduced in medium-sized lithium-air batteries, the materials give very high specific capacity (up to 2.3 A h g,1). These materials are also catalytically tested in the oxidation of toluene with molecular oxygen at atmospheric pressure, showing significant oxidative catalytic activities in this difficult chemical reaction. [source] Novel Solid Acid Catalysts: Sulfonic Acid Group-Functionalized Mesostructured Polymers,ADVANCED FUNCTIONAL MATERIALS, Issue 14 2007R. Xing Abstract Novel solid acid catalysts have been prepared from Fudan University (FDU)-type mesoporous polymers with the Ia d and P6mm mesostructures through a carefully controlled sulfonation procedure. Various techniques have been adopted to characterize throughout their structures, porosity, acidity as well as the information related to the sulfonic acid groups. The sulfonic acid group-functionalized mesopolymers prove to be efficient heterogeneous catalysts in the reactions such as liquid-phase Beckmann rearrangement of cyclohexanone oxime and condensation of ethylene glycol with the aldehydes having different molecular sizes. [source] Fluid regimens for colostomy irrigation: a systematic reviewINTERNATIONAL JOURNAL OF EVIDENCE BASED HEALTHCARE, Issue 3 2008Lucylynn Lizarondo Abstract Background, Various techniques for managing faecal evacuation have been proposed; however, colostomy irrigation is favoured as it leads to better patient outcomes. Alternative fluid regimens for colostomy irrigation have been suggested to achieve effective evacuation. Aim, The objective of this review was to summarise the best available evidence on the most effective fluid regimen for colostomy irrigation. Search strategy, Trials were identified by electronic searches of CINAHL, PubMed, MEDLINE, Current Contents, the Cochrane Library and EMBASE. Unpublished articles and references lists from included studies were also searched. Selection criteria, Randomised controlled trials and before-and-after studies investigating any fluid regimen for colostomy irrigation were eligible for inclusion. Outcomes measured included fluid inflow time, total wash-out time, haemodynamic changes during irrigation, cramps, leakage episodes, quality of life and level of satisfaction. Data collection and analysis, Trial selection, quality appraisal and data extraction were carried out independently by two reviewers. Differences in opinion were resolved by discussion. Main results, The systematic literature search strategy identified two cross-over trials that compared water with another fluid regimen. Owing to the differences in irrigating solutions used, the results were not pooled for analysis. Both the polyethylene glycol electrolyte solution and glyceryl trinitrate performed significantly better than water. Conclusion, There is some evidence to support the effectiveness of fluid regimens other than water, such as polyethylene glycol electrolyte and glyceryl trinitrate, for colostomy irrigation. Further well-designed clinical trials are required to establish solid evidence on the effectiveness of other irrigating solutions that might enhance colonic irrigation. [source] Synthesis of copolymer from 1,3,5-trioxane and 1,3-dioxolane catalyzed by Maghnite-H+JOURNAL OF APPLIED POLYMER SCIENCE, Issue 5 2010Khadidja Beloufa Abstract Copolymers (polyoxymethylene) were prepared by cationic copolymerization of 1,3,5-trioxane (TOX) with 1,3-dioxolane (DOX) in the presence of Maghnite-H+ (Mag-H+) in solution. Maghnite is a Montmorillonite sheet silicate clay, with exchanged protons to produce Mag-H+. Various techniques, including 1H-NMR, 13C-NMR, FT-IR spectroscopy, and Ubbelohde viscometer were used to elucidate structural characteristics properties of the resulting copolymers. The influence of the amount of catalyst, of dioxolane (DOX), temperature, solvent, and time of copolymerization on yield and on intrinsic viscosity of copolymers was studied. The yield of copolymerization depends on the amount of Mag-H+ used and the reaction time. We also propose mechanisms involved in the synthesis of copolymer (polyoxymethylene). © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2010 [source] Improved k -space trajectory measurement with signal shiftingMAGNETIC RESONANCE IN MEDICINE, Issue 1 2007Marine Beaumont Abstract Various techniques for k -space trajectory measurement have been described in the literature. Self-encoding gradient techniques are time-consuming due to the high number of phase-encoding steps needed. The approach with localized slices is faster, but its use apparently has not been reported in the context of high spatial resolution experiments. Signals associated with high k -space frequencies may then reach low or even zero values, and this may result in errors in the estimate of the trajectories at the k -space periphery. To overcome this problem without increasing the measurement duration of the localized slice method too much, a new approach is proposed in which an addition dephasing gradient applied prior to the gradient to be measured shifts the signal maximum. Magn Reson Med 58:200,205, 2007. © 2007 Wiley-Liss, Inc. [source] Peptide-based radiopharmaceuticals: Future tools for diagnostic imaging of cancers and other diseasesMEDICINAL RESEARCH REVIEWS, Issue 3 2004S.M. Okarvi Abstract An Erratum has been published for this article in Medicinal Research Reviews 2004;24:685,686. Small synthetic receptor-binding peptides are the agents of choice for diagnostic imaging and radiotherapy of cancers due to their favorable pharmacokinetics. Molecular modification techniques permit the synthesis of a variety of bioactive peptides with chelating groups, without compromising biological properties. Various techniques have been developed that allow efficient and site-specific labeling of peptides with clinically useful radionuclides such as 99mTc, 123I, 111In, and 18F. Among them, 99mTc is the radionuclide of choice because of its excellent chemical and imaging characteristics. Recently, many 99mTc-labeled peptides have proven to be useful imaging agents. Beside 99mTc-labeled peptides, several peptides radiolabeled with 111In and 123I have been prepared and characterized. In addition, 18F-labeled peptides hold clinical potential due to their ability to quantitatively detect and characterize a variety of human diseases using positron-emission tomography. The availability of this wide range of peptides labeled with different radionuclides offers multiple diagnostic and therapeutic applications. Various receptors are over-expressed in particular tumor types and peptides binding to these receptors can be used to visualize tumor lesions scintigraphically. Thus, radiolabeled peptides have potential use as carriers for the delivery of radionuclides to tumors, infarcts, and infected tissues for diagnostic imaging and radiotherapy. Many radiolabeled peptides are currently under investigation to determine their potential as imaging agents. These peptides are designed mainly for thrombus, tumor, and infection/inflammation imaging. This article presents recent developments in small synthetic peptides for imaging of thrombosis, tumors, and infection/inflammation. © 2004 Wiley Periodicals, Inc. Med Res Rev, 24, No. 3, 357,397, 2004 [source] Jacobi,Davidson methods for cubic eigenvalue problemsNUMERICAL LINEAR ALGEBRA WITH APPLICATIONS, Issue 7 2005Tsung-Min Hwang Abstract Several Jacobi,Davidson type methods are proposed for computing interior eigenpairs of large-scale cubic eigenvalue problems. To successively compute the eigenpairs, a novel explicit non-equivalence deflation method with low-rank updates is developed and analysed. Various techniques such as locking, search direction transformation, restarting, and preconditioning are incorporated into the methods to improve stability and efficiency. A semiconductor quantum dot model is given as an example to illustrate the cubic nature of the eigenvalue system resulting from the finite difference approximation. Numerical results of this model are given to demonstrate the convergence and effectiveness of the methods. Comparison results are also provided to indicate advantages and disadvantages among the various methods. Copyright © 2004 John Wiley & Sons, Ltd. [source] An investigation of the effect of silane water-crosslinking on the properties of poly(L-lactide)POLYMER INTERNATIONAL, Issue 5 2010Changyu Han Abstract A silane-grafting water-crosslinking approach was developed to crosslink poly(L -lactide) (PLLA) by grafting vinylalkoxysilane onto PLLA using dicumyl peroxide, followed by silane hydrolysis to form siloxane linkages between PLLA chains. The degree of silane grafting onto PLLA was qualitatively characterized using Fourier transform infrared spectroscopy and quantitatively determined using inductively coupled plasma mass spectrometry. Crosslinked PLLA films were obtained by curing of silane-grafted PLLA in hot water. Gel fractions were evaluated in order to calculate the crosslinking reaction kinetics and crosslinking density. Various techniques were used to investigate the effect of silane water-crosslinking on the thermomechanical properties, hydrolysis resistance and biodegradation of PLLA. In addition to an improvement in thermal stability and mechanical properties, hydrolysis resistance was significantly enhanced as a result of silane water-crosslinking of PLLA. Moreover, the biodegradation of silane water-crosslinked PLLA was retarded compared with neat PLLA. Copyright © 2010 Society of Chemical Industry [source] Interventions for replacing missing teeth: bone augmentation techniques for dental implant treatmentAUSTRALIAN DENTAL JOURNAL, Issue 1 2009M Esposito Background:, Dental implants require sufficient bone to be adequately stabilized. For some patients implant treatment would not be an option without bone augmentation. A variety of materials and surgical techniques are available for bone augmentation. Objectives:, General objectives: To test the null hypothesis of no difference in the success, function, morbidity and patient satisfaction between different bone augmentation techniques for dental implant treatment. Specific objectives: (A) to test whether and when augmentation procedures are necessary; (B) to test which is the most effective augmentation technique for specific clinical indications. Trials were divided into three broad categories according to different indications for the bone augmentation techniques: (1) major vertical or horizontal bone augmentation or both; (2) implants placed in extraction sockets; (3) fenestrated implants. Search strategy:, The Cochrane Oral Health Group's Trials Register, the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE and EMBASE were searched. Several dental journals were handsearched. The bibliographies of review articles were checked, and personal references were searched. More than 55 implant manufacturing companies were also contacted. Last electronic search was conducted on 9 January 2008. Selection criteria:, Randomized controlled trials (RCTs) of different techniques and materials for augmenting bone for implant treatment reporting the outcome of implant therapy at least to abutment connection. Data collection and analysis:, Screening of eligible studies, assessment of the methodological quality of the trials and data extraction were conducted independently and in duplicate. Authors were contacted for any missing information. Results were expressed as random-effects models using mean differences for continuous outcomes and odd ratios for dichotomous outcomes with 95% confidence intervals. The statistical unit of the analysis was the patient. Main results:, Seventeen RCTs out of 40 potentially eligible trials reporting the outcome of 455 patients were suitable for inclusion. Since different techniques were evaluated in different trials, no meta-analysis could be performed. Ten trials evaluated different techniques for vertical or horizontal bone augmentation or both. Four trials evaluated different techniques of bone grafting for implants placed in extraction sockets and three trials evaluated different techniques to treat bone dehiscence or fenestrations around implants. Authors' conclusions:, Major bone grafting procedures of resorbed mandibles may not be justified. Bone substitutes (Bio-Oss or Cerasorb) may replace autogenous bone for sinus lift procedures of atrophic maxillary sinuses. Various techniques can augment bone horizontally and vertically, but it is unclear which is the most efficient. It is unclear whether augmentation procedures at immediate single implants placed in fresh extraction sockets are needed, and which is the most effective augmentation procedure, however, sites treated with barrier plus Bio-Oss showed a higher position of the gingival margin when compared to sites treated with barriers alone. Non-resorbable barriers at fenestrated implants regenerated more bone than no barriers, however it remains unclear whether such bone is of benefit to the patient. It is unclear which is the most effective technique for augmenting bone around fenestrated implants. Bone morphogenetic proteins may enhance bone formation around implants grafted with Bio-Oss. Titanium may be preferable to resorbable screws to fixate onlay bone grafts. The use of particulate autogenous bone from intraoral locations, also taken with dedicated aspirators, might be associated with an increased risk of infective complications. These findings are based on few trials including few patients, sometimes having short follow up, and often being judged to be at high risk of bias. [source] Models for Bounded Systems with Continuous DynamicsBIOMETRICS, Issue 3 2009Amanda R. Cangelosi Summary Models for natural nonlinear processes, such as population dynamics, have been given much attention in applied mathematics. For example, species competition has been extensively modeled by differential equations. Often, the scientist has preferred to model the underlying dynamical processes (i.e., theoretical mechanisms) in continuous time. It is of both scientific and mathematical interest to implement such models in a statistical framework to quantify uncertainty associated with the models in the presence of observations. That is, given discrete observations arising from the underlying continuous process, the unobserved process can be formally described while accounting for multiple sources of uncertainty (e.g., measurement error, model choice, and inherent stochasticity of process parameters). In addition to continuity, natural processes are often bounded; specifically, they tend to have nonnegative support. Various techniques have been implemented to accommodate nonnegative processes, but such techniques are often limited or overly compromising. This article offers an alternative to common differential modeling practices by using a bias-corrected truncated normal distribution to model the observations and latent process, both having bounded support. Parameters of an underlying continuous process are characterized in a Bayesian hierarchical context, utilizing a fourth-order Runge,Kutta approximation. [source] Pt Nanoparticles Supported on Highly Dispersed Alumina Coated inside SBA-15 for Enantioselective HydrogenationCHEMCATCHEM, Issue 10 2010Hongna Wang Abstract A series of Al2O3@SBA-15 composites with different alumina loadings have been prepared using a solid-state grinding method. Various techniques, such as X-ray diffraction, N2,sorption, FT-IR spectroscopy, and NMR spectroscopy, are used to characterize their structures and acidity. The Al2O3@SBA-15 composites retain the mesostructure of the SBA-15 host and the alumina is highly dispersed and uniformly coated inside the mesopores. The Al2O3@SBA-15 composites serve as remarkable supports for Pt nanoparticles, which can be used as catalysts in the enantioselective hydrogenation of ethyl pyruvate. Both the Brønsted acid sites that originate from the interface of Al2O3 and SBA-15 in the Al2O3@SBA-15 composites and the appropriate interaction of Pt nanoparticles with alumina coated inside the mesopores of SBA-15 can improve the catalytic behavior of Pt/Al2O3@SBA-15 catalysts. [source] Cells meeting our immunophenotypic criteria of endothelial cells are large plateletsCYTOMETRY, Issue 2 2007Michiel H. Strijbos Abstract Background Circulating endothelial cells (CEC) are shed from damaged vasculature, making them a rational choice to serve as surrogate marker for vascular damage. Currently, various techniques and CEC definitions are in use, and their standardization and validation is needed. A flow cytometric single platform assay defining CEC as forward light scatter (FSC)low-to-intermedate, sideward light scatter (SSC)low, CD45,, CD31++ and CD146+ is a promising approach to enumerate CEC because of its simplicity (Mancuso et al., Blood 2001;97:3658,3661). Here, we set out to confirm the endothelial nature of these cells. Methods We isolated cells with a FSClow-to-intermediate, SSClow, CD31++, CD45dim immunophenotype (termed "cells meeting our immunophenotypic criteria for endothelial cells" [CMOIC]) from healthy donors to study the expression of endothelium-associated markers using several techniques. Special attention was paid to reagents identifying the endothelial cell-specific marker CD146. We compared antigen expression patterns of CMOIC with those of the HUVEC endothelial cell line and lymphocytes. Electron microscopy was used to detect the presence of endothelial cell-specific Weibel,Palade bodies in the sorted cells. Results CD146 expression was negative on CMOIC for all tested CD146 mAbs, but positive on HUVEC cells and a minor subset of T lymphocytes. Using flow cytometry, we found no expression of any endothelium-associated marker except for CD31 and CD34. HUVEC cells were positive for all endothelial markers except for CD34. Evaluation of CMOIC morphology showed a homogenous population of cells with a highly irregular nucleus-like structure and positive endothelial immunohistochemistry. CMOIC contained neither nuclei nor DNA. Electron microscopy revealed the absence of a nucleus, the absence of endothelial specific Weibel,Palade bodies, and revealed CMOIC to be large platelets. Conclusion The vast majority of cells with the immunophenotype FSClow-to-intermediate, SSClow, CD45,, CD31++ do not express CD146 and are large platelets rather than endothelial cells. © 2007 Clinical Cytometry Society. [source] Intricacies of the Single-Scar Technique for Donor Harvesting in Hair Transplantation SurgeryDERMATOLOGIC SURGERY, Issue 6 2004Dominic A. Brandy MD Background. Although single-scar techniques have been published and are used by approximately half of all surgeons, this approach is not as common as one might suspect. Objective. The objective is to demonstrate several surgical gems that make the single-scar donor technique a viable method that can be performed by the vast majority of hair restoration surgeons. Methods. The author presents various techniques such as postauricular skin elevation, subcutaneous undermining of the nape scalp, debulking of underlying scar tissue, temporary staple closure, and permanent double-layered closure using magnification (preferably 2.5 × or greater). All of these contribute to a loose closure with an aesthetically pleasing single donor scar after multiple surgeries. Results. Utilizing the various techniques described in this article, the author has been able to achieve a cosmetically attractive single scar after multiple surgeries in the vast majority of patients. Conclusion. An aesthetically pleasing single, thin donor scar is preferable to multiple scars or a thick single scar at the donor area after multiple hair restoration surgical procedures. The author presents several methods that help hair restoration surgeons conquer some of the obstacles that have deterred them from performing a single-scar technique with consistently excellent results. [source] Inorganic Analogues of GrapheneEUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 27 2010C. N. R. Rao Abstract The discovery of graphene has aroused great interest in the properties and phenomena exhibited by two-dimensional inorganic materials, especially when they comprise only a single, two or a few layers. Graphene-like MoS2 and WS2 have been prepared by chemical methods, and the materials have been characterized by electron microscopy, atomic force microscopy (AFM) and other methods. Boron nitride analogues of graphene have been obtained by a simple chemical procedure starting with boric acid and urea and have been characterized by various techniques that include surface area measurements. A new layered material with the composition BCN possessing a few layers and a large surface area discovered recently exhibits a large uptake of CO2. [source] Identification of phospholipids as new components that assist in the in vitro trimerization of a bacterial pore proteinFEBS JOURNAL, Issue 3 2001Hans De Cock The in vitro trimerization of folded monomers of the bacterial pore protein PhoE, into its native-like, heat- and SDS-stable form requires incubations with isolated cell envelopes and Triton X-100. The possibility that membranes could be isolated that are enriched in assembly factors required for assembly of the pore protein was now investigated. Fractionation of total cell envelopes of Escherichia coli via various techniques indeed revealed the existence of membrane fractions with different capacities to support assembly in vitro. Fractions containing mainly inner membrane vesicles supported the formation of trimers that were associated with these membrane vesicles. However, only a proportion of these trimers were heat- and SDS-stable and these were formed with slow kinetics. In contrast, fractions containing mainly outer membrane vesicles supported formation of high amounts of heat-stable trimers with fast kinetics. We identified phospholipids as active assembly components in these membranes that support trimerization of folded monomers in a process with similar characteristics as observed with inner membrane vesicles. Furthermore, phospholipids strongly stimulate the kinetics of trimerization and increase the final yield of heat-stable trimers in the context of outer membranes. We propose that lipopolysaccharides stabilize the assembly competent state of folded monomers as a lipochaperone. Phospholipids are involved in converting the folded monomer into new assembly competent intermediate with a short half-life that will form heat-stable trimers most efficiently in the context of outer membrane vesicles. These results provide biochemical evidence for the involvement of different lipidic components at distinct stages of the porin assembly process. [source] Genotyping errors, pedigree errors, and missing dataGENETIC EPIDEMIOLOGY, Issue S1 2005Anthony L. Hinrichs Abstract Our group studied the effects of genotyping errors, pedigree errors, and missing data on a wide range of techniques, with a focus on the role of single-nucleotide polymorphisms (SNPs). Half of our group used simulated data, and half of our group used data from the Collaborative Study on the Genetics of Alcoholism (COGA). The simulated data had no missing genotypes and no genotyping errors, so our group, as a whole, removed data and introduced artificial errors to study the robustness of various techniques. Our teams showed that genotyping errors are less detectable and may have a greater impact on SNPs than on microsatellites, but recently developed methods that account for genotyping errors help reduce false positives, and the assumptions of these methods appear to be supported by observations from repeated genotyping. The ability to detect linkage disequilibrium (LD) was also substantially reduced by missing data; this in turn could affect tagging SNPs chosen to generate haplotypes. In the COGA sample, genotyping measurements were repeated in three ways. First, full-genome screens were performed on three sets of markers: 328 microsatellites, 11,560 SNPs from the Affymetrix GeneChip Mapping 10,K Array marker set, and 4,720 SNPs from the Illumina Linkage III panel. Second, the entire Affymetrix marker set was typed on the same 184 individuals by two different laboratories. Finally, the Affymetrix and Illumina marker panels had 94 SNPs in common. Our teams showed that both SNPs and microsatellites can be readily used to identify pedigree errors, and that SNPs have fewer genotyping errors and a low inconsistency rate. However, a fairly high rate of no-calls, especially for the Affymetrix platform, suggests that the inconsistency rate may be higher than observed. Genet. Epidemiol. 29(Suppl. 1):S120,S124, 2005. © 2005 Wiley-Liss, Inc. [source] Techniques for liver parenchymal transection: a meta-analysis of randomized controlled trialsHPB, Issue 4 2009Viniyendra Pamecha Abstract Background:, Different techniques of liver parenchymal transection have been described, including the finger fracture, sharp dissection, clamp,crush methods and, more recently, the Cavitron ultrasonic surgical aspirator (CUSA), the hydrojet and the radiofrequency dissection sealer (RFDS). This review assesses the benefits and risks associated with the various techniques. Methods:, Randomized clinical trials were identified from the Cochrane Library Trials Register, MEDLINE, EMBASE, Science Citation Index Expanded and reference lists. Odds ratio (ORs), mean difference (MDs) and standardized mean differences (SMDs) were calculated with 95% confidence intervals based on intention-to-treat analysis or available-case analysis. Results:, We identified seven trials including a total of 556 patients. Blood transfusion requirements were lower with the clamp,crush technique than with the CUSA or hydrojet. The clamp,crush technique was quicker than the CUSA, hydrojet or RFDS. Infective complications and transection blood loss were greater with the RFDS than with the clamp,crush method. There was no significant difference between techniques in mortality, morbidity, liver dysfunction or intensive therapy unit and hospital stay. Conclusions:, The clamp,crush technique is more rapid and is associated with lower rates of blood loss and otherwise similar outcomes when compared with other methods of parenchymal transection. It represents the reference standard against which new methods may be compared. [source] Bulk Heterojunction Solar Cells: The Role of Processing in the Fabrication and Optimization of Plastic Solar Cells (Adv. Mater.ADVANCED MATERIALS, Issue 14-15 200915/2009) Alan Heeger and co-workers report on page 1521 on the role of processing methodology in the fabrication and optimization of bulk heterojunction (BHJ) ,plastic' solar cells. Several techniques that have recently been used to optimize the BHJ nanomorphology are discussed and compared and some insights are given into the mechanisms behind these various techniques. The cover image depicts a multilayer solar cell ribbon along with the polymer, fullerene, and solvent additive, which were used to fabricate a low bandgap polymer solar cell with greater than 5% power conversion efficiency. [source] Effectiveness of different techniques for removing gutta-percha during retreatmentINTERNATIONAL ENDODONTIC JOURNAL, Issue 1 2005A. V. Masiero Abstract Aim, To evaluate the effectiveness of various techniques for removing filling material from root canals in vitro. Methodology, Eighty extracted mandibular premolar teeth were selected for the study. The teeth were root filled using thermomechanical compaction of gutta-percha. After 8 months, the filling material was removed and canals were reinstrumented using the following techniques: group I , hand instrumentation with K-type files (SybronEndo, Orange, CA, USA); group II , K3 Endo System (SybronEndo); group III , M4 system (SybronEndo) with K-type files (SybronEndo); and group IV , Endo-gripper system (Moyco Union Broach, York, PA, USA) with K-type files (SybronEndo). The amount of filling debris remaining on root canal walls was assessed radiographically; the images were digitized and analysed using AutoCAD 2000 software. Total canal area, area of the cervical, middle and apical thirds, and area of remaining filling material were outlined by one operator. The ratios between these areas were calculated as percentages of remaining debris. Thereafter, data were analysed by means of one-way anova and the post-hoc Duncan test to identify differences between the four techniques. Results, Multiple comparisons of the percentages of remaining filling material in the entire canal did not reveal any significant differences between the methods of removal. However, when each third was analysed separately, significant differences for remaining debris were present between groups. The apical third had the most remaining material, whilst the cervical and middle thirds were significantly cleaner (P = 0.002). Comparison of the techniques revealed that teeth instrumented with K3 rotary instruments had a lower ratio of remaining filling material in the apical third (P = 0.012). Conclusion, In the apical third, K3 rotary instruments were more efficient in removing gutta-percha filling material than the other techniques, which were equally effective for the other thirds. [source] Tensor visualizations in computational geomechanicsINTERNATIONAL JOURNAL FOR NUMERICAL AND ANALYTICAL METHODS IN GEOMECHANICS, Issue 10 2002Boris Jeremi Abstract We present a novel technique for visualizing tensors in three dimensional (3D) space. Of particular interest is the visualization of stress tensors resulting from 3D numerical simulations in computational geomechanics. To this end we present three different approaches to visualizing tensors in 3D space, namely hedgehogs, hyperstreamlines and hyperstreamsurfaces. We also present a number of examples related to stress distributions in 3D solids subjected to single and load couples. In addition, we present stress visualizations resulting from single-pile and pile-group computations. The main objective of this work is to investigate various techniques for visualizing general Cartesian tensors of rank 2 and it's application to geomechanics problems. Copyright © 2002 John Wiley & Sons, Ltd. [source] Isolating the root cause of propagated oscillations in process plantsINTERNATIONAL JOURNAL OF ADAPTIVE CONTROL AND SIGNAL PROCESSING, Issue 4 2005Xiaoyun Zang Abstract Oscillations are a common type of propagated disturbance, whose sources might be attributable to a number of different phenomena such as poor controller tuning or actuator nonlinearity. A number of data-driven methods have already been proposed to isolate the source loop of nonlinearity induced plant-wide oscillations. Amongst these the bi-amplitude ratio index, correlation dimension, maximal Lyapunov exponent, nonlinearity index and spectral ICA show promise. The propagation of oscillations is first examined in order to gain an understanding of how this might affect the performances of the various techniques. The various methods are then described and their performance on a set of simulation generated data and two industrial case studies are compared. Copyright © 2004 John Wiley & Sons, Ltd. [source] Preparation and thermal decomposition reaction kinetics of a dysprosium(III) p -chlorobenzoate 1,10-phenanthroline complexINTERNATIONAL JOURNAL OF CHEMICAL KINETICS, Issue 2 2008Jian Jun Zhang The title complex [Dy(p -ClBA)3Phen]2·2H2O was synthesized, where p -ClBA is p -chlorobenzoate and Phen is 1,10-phenanthroline. The complex was characterized by various techniques including elemental analysis, IR, XRD, and molar conductance. The thermal decomposition of the complex was studied under the nonisothermal condition by TG-DTG and IR techniques. The kinetic parameters of dehydration process were obtained from the analysis of DSC curves of the complex by the NL-DIF and Popescu methods, respectively. © 2007 Wiley Periodicals, Inc. 40: 66,72, 2008 [source] Review of systems for monitoring curd setting during cheesemakingINTERNATIONAL JOURNAL OF DAIRY TECHNOLOGY, Issue 2 2002Donal J O'Callaghan This paper reviews the current state of development of various techniques for monitoring coagulum formation in cheesemaking, and the implications of recent research findings. The techniques, which have become available for on-line use on modern cheese vats include hot wire probes, vibrating probes and several types of optical probe. Recent research has focused on comparing the various techniques against a background of cheese manufacture from milk with seasonal variation. The findings indicate that on-line techniques can improve the consistency of coagulum at cutting in a modern cheese factory. [source] New model for the formation and function of sagittocysts: Symsagittifera corsicae n. sp. (Acoela)INVERTEBRATE BIOLOGY, Issue 2 2002Robert Gschwentner Abstract. This study is focused on the formation and function of sagittocysts, which are secretions typical of members of the acoel family Sagittiferidae. The needle-shaped sagittocysts are produced in specialized gland cells (sagittocytes) whose distal necks are often surrounded by muscle mantles. Contraction of the muscle mantle ejects the sagittocyst. We establish a model for the development of sagittocytes and muscle mantles out of the stem cell pool of the new acoel species Symsagittifera corsicae. We used various techniques, especially interference and phase-contrast microscopy of living specimens as well as labeling of the body-wall musculature, for species characterization. In addition to the morphological features, we provide the third complete sequence of the 18S rDNA gene in the family Sagittiferidae. [source] Synthesis and characterization of novel polyimide/SiO2 nanocomposite materials containing phenylphosphine oxide via sol-gel techniqueJOURNAL OF APPLIED POLYMER SCIENCE, Issue 6 2010Canan Kizilkaya Abstract In this article, a series of novel polyimide/silica (PI/SiO2) nanocomposite coating materials were prepared from tetraethoxysilane (TEOS), ,-glycidyloxypropyltrimethoxysilane (GOTMS), and polyamic acid (PAA) via sol-gel technique. PAA was prepared by the reaction of 3,3,,4,4,-benzophenone tetracarboxylic dianhydride (BTDA) and bis (3-aminophenyl) phenyphosphine oxide (BAPPO) in N -methyl-2- pyrrolidone (NMP). BAPPO was synthesized hydrogenation of bis (3-nitrophenyl) phenyphosphine oxide (BNPPO) in the presence of Pd/C. The silica content in the hybrid coating materials was varied from 0 to 20 wt %. The molecular structures of the composite materials were analyzed by means of FT-IR and 29Si-NMR spectroscopy techniques. The physical and mechanical properties of the nanocomposites were evaluated by various techniques such as, hardness, contact angle, and optical transmission and tensile tests. These measurements revealed that all the properties of the nanocomposite coatings were improved noticeable, by the addition of sol-gel precursor into the coating formulation. Thermogravimetric analysis showed that the incorporation of sol-gel precursor into the polyimide matrix leads to an enhancement in the thermal stability and also flame resistance properties of the coating material. The surface morphology of the hybrid coating was characterized by scanning electron microscopy (SEM). SEM studies indicated that nanometer-scaled inorganic particles were homogenously dispersed throughout the polyimide matrix © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2010 [source] Advanced glycation end products: a highly complex set of biologically relevant compounds detected by mass spectrometry,JOURNAL OF MASS SPECTROMETRY (INCORP BIOLOGICAL MASS SPECTROMETRY), Issue 4 2001Annunziata Lapolla Abstract Structural information on ,AGE-peptides,' a class of substances belonging to advanced glycation end products (AGE) and originating by proteolysis of glycated proteins, was gained through various analytical approaches on the mixture produced by proteinase K digestion of in vitro glycated bovine serum albumin. Both matrix-assisted laser desorption/ionization mass spectrometry (MALDI-MS) and high-performance liquid chromatography/electrospray ionization mass spectrometry (HPLC/ESI-MS) were employed, and the results were compared with those from conventional spectroscopic methods (UV, fluorescence, gel permeation). The data acquired by the various techniques all depict the digestion mixtures as highly complex, with components exhibiting molecular mass in the range 300,3500 Da. In the analysis of HPLC/ESI-MS data, identification of AGE-peptides was facilitated by 3D mapping. Structural information was gained by means of multiple mass spectrometric experiments. Copyright © 2001 John Wiley & Sons, Ltd. [source] Building the capacity for evidence-based clinical nursing leadership: the role of executive co-coaching and group clinical supervision for quality patient servicesJOURNAL OF NURSING MANAGEMENT, Issue 2 2007BA (Hons), JO ALLEYNE DProf Aim, The general aims of this article were to facilitate primary care nurses (District Nurse Team Leaders) to link management and leadership theories with clinical practice and to improve the quality of the service provided to their patients. The specific aim was to identify, create and evaluate effective processes for collaborative working so that the nurses' capacity for clinical decision-making could be improved. Background, This article, part of a doctoral study on Clinical Leadership in Nursing, has wider application in the workplace of the future where professional standards based on collaboration will be more critical in a world of work that will be increasingly complex and uncertain. This article heralds the type of research and development activities that the nursing and midwifery professions should give premier attention to, particularly given the recent developments within the National Health Service in the United Kingdom. The implications of: Agenda for Change, the Knowledge and Skills Framework, ,Our Health, Our Care, Our Say' and the recent proposals from the article Modernising Nursing Career, to name but a few, are the key influences impacting on and demanding new ways of clinical supervision for nurses and midwives to improve the quality of patient management and services. Method, The overall approach was based on an action research using a collaborative enquiry within a case study. This was facilitated by a process of executive co-coaching for focused group clinical supervision sessions involving six district nurses as co-researchers and two professional doctoral candidates as the main researchers. The enquiry conducted over a period of two and a half years used evidence-based management and leadership interventions to assist the participants to develop ,actionable knowledge'. Group clinical supervision was not practised in this study as a form of ,therapy' but as a focus for the development of actionable knowledge, knowledge needed for effective clinical management and leadership in the workplace. Findings, ,,Management and leadership interventions and approaches have significantly influenced the participants' capacity to improve the quality of services provided to their patients. ,,Using various techniques, tools, methods and frameworks presented at the sessions increased participants' confidence to perform. ,,A structured approach like the Clinical Nursing Leadership Learning and Action Process (CLINLAP) model makes implementing change more practical and manageable within a turbulent care environment. The process of Stakeholder Mapping and Management made getting agreement to do things differently much easier. Generally it is clear that many nurses and midwives, according to the participants, have to carry out management and leadership activities in their day-to-day practice. The traditional boundary between the private, the public and the voluntary sector management is increasingly becoming blurred. Conclusion, It is conclusive that the district nurses on this innovative programme demonstrated how they were making sense of patterns from the past, planning for the future and facilitating the clinical nursing leadership processes today to improve quality patient services tomorrow. Their improved capacity to manage change and lead people was demonstrated, for example, through their questioning attitudes about the dominance of general practitioners. They did this, for example, by initiating and leading case conferences with the multi-disciplinary teams. It became evident from this study that to use group clinical supervision with an executive co-coaching approach for the implementation and to sustain quality service demand that ,good nursing' is accepted as being synonymous with ,good management'. This is the future of ,new nursing'. [source] A hyperbranched, rotaxane-type mechanically interlocked polymerJOURNAL OF POLYMER SCIENCE (IN TWO SECTIONS), Issue 18 2010Shijun Li Abstract Based on the dibenzo-24-crown-8/1,2-bis(pyridinium)ethane recognition motif, a hyperbranched mechanically interlocked polymer was prepared by polyesterification of an easily available dynamic trifunctional AB2 pseudorotaxane monomer. It was characterized by various techniques including 1H NMR, COSY, NOESY, GPC, viscosity, TGA, dynamic laser light scattering, AFM, and SEM. Its GPC Mn was determined to be 191 kDa with polydispersity 1.7 and its hydrodynamic diameter in a dilute solution in acetone was about 70 nm. This measured Mn value corresponds to about 93 repeating units. The study reported here presents not only a new polymer topology but also a novel and convenient way to prepare mechanically interlocked polymers. © 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 48: 4067,4073, 2010 [source] | ||||||||||||||||||||||||||||||||||||||||||||||