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Another Method (another + method)
Selected AbstractsRole of Orthopedic Implants and Bone Morphology in the Identification of Human RemainsJOURNAL OF FORENSIC SCIENCES, Issue 2 2007Ellie K. Simpson Ph.D. ABSTRACT: When conventional methods of identification, such as visual recognition and dental comparison, cannot be used to identify a deceased person, it becomes necessary to consider alternative methods. The presence of an orthopedic implant in a body may assist identification if ante-mortem medical records are available for comparison. Another method of identification involves comparison of ante-mortem and postmortem radiographs. Eight cases are reported from Forensic Science SA where the presence of orthopedic implants and/or ante-mortem radiographs were used to try to establish identification. In six cases, positive identification was established, and in two cases with upper limb orthopedic implants, the bones remained unidentified. Manufacturers were unable to provide any information about the distribution and use of the implants that could be of use with identification, as there are no requirements in Australia for individual medical implants to be tracked. Such a system has the potential to aid postmortem identification if serial codes were etched onto implants that could then be traced to manufacturers, surgeons, and recipients of these devices. [source] An unsupervised classification method of uterine electromyography signals: Classification for detection of preterm deliveriesJOURNAL OF OBSTETRICS AND GYNAECOLOGY RESEARCH (ELECTRONIC), Issue 1 2009M. O. Diab Abstract Aim:, This article proposes an unsupervised classification method that can be applied to the electromyography signal of uterine contractions for the detection of preterm birth. Methods:, The frequency content of the electromyography changes from one woman to another, and during pregnancy, so wavelet decomposition is first used to extract the parameters of each contraction, and an unsupervised statistical classification method based on Fisher's test is used to classify the events. A principal component analysis projection is then used as evidence of the groups resulting from this classification. Another method of classification based on a competitive neural network is also applied on the same signals. Both methods are compared. Results:, Results show that uterine contractions may be classified into independent groups according to their frequency content and according to term (either at recording or at delivery). [source] Recent advances in de novo design strategy for practical lead identificationMEDICINAL RESEARCH REVIEWS, Issue 5 2003Teruki Honma Abstract De novo design programs such as LEGEND, LUDI, and LeapFrog can identify novel structures that are predicted to fit the active site of a target protein. However, in the conventional de novo design strategy, the output structures obtained from the programs can be problematic with regard to synthetic accessibility and binding affinity prediction. Thus it has been practically difficult to obtain novel lead compounds that are appropriate for medicinal chemists through the de novo design strategy. Since the late 1990s, several new strategies for lead identification have been reported and the successful examples have been disclosed. One of the strategies is validation of small fragments, which can be substructures of de novo ligands, by using NMR, X-ray, or MS spectra. Another method is prioritization of output structures obtained from de novo design programs by chemical accessibility. This review describes these new strategies with practical applications and future perspectives of de novo design. © 2003 Wiley Periodicals, Inc. Med Res Rev, 23, No. 5, 606,632, 2003 [source] Statistical power when testing for genetic differentiationMOLECULAR ECOLOGY, Issue 10 2001N. Ryman Abstract A variety of statistical procedures are commonly employed when testing for genetic differentiation. In a typical situation two or more samples of individuals have been genotyped at several gene loci by molecular or biochemical means, and in a first step a statistical test for allele frequency homogeneity is performed at each locus separately, using, e.g. the contingency chi-square test, Fisher's exact test, or some modification thereof. In a second step the results from the separate tests are combined for evaluation of the joint null hypothesis that there is no allele frequency difference at any locus, corresponding to the important case where the samples would be regarded as drawn from the same statistical and, hence, biological population. Presently, there are two conceptually different strategies in use for testing the joint null hypothesis of no difference at any locus. One approach is based on the summation of chi-square statistics over loci. Another method is employed by investigators applying the Bonferroni technique (adjusting the P -value required for rejection to account for the elevated alpha errors when performing multiple tests simultaneously) to test if the heterogeneity observed at any particular locus can be regarded significant when considered separately. Under this approach the joint null hypothesis is rejected if one or more of the component single locus tests is considered significant under the Bonferroni criterion. We used computer simulations to evaluate the statistical power and realized alpha errors of these strategies when evaluating the joint hypothesis after scoring multiple loci. We find that the ,extended' Bonferroni approach generally is associated with low statistical power and should not be applied in the current setting. Further, and contrary to what might be expected, we find that ,exact' tests typically behave poorly when combined in existing procedures for joint hypothesis testing. Thus, while exact tests are generally to be preferred over approximate ones when testing each particular locus, approximate tests such as the traditional chi-square seem preferable when addressing the joint hypothesis. [source] Pharmacokinetic parameters estimation using adaptive Bayesian P-splines modelsPHARMACEUTICAL STATISTICS: THE JOURNAL OF APPLIED STATISTICS IN THE PHARMACEUTICAL INDUSTRY, Issue 2 2009Astrid Jullion Abstract In preclinical and clinical experiments, pharmacokinetic (PK) studies are designed to analyse the evolution of drug concentration in plasma over time i.e. the PK profile. Some PK parameters are estimated in order to summarize the complete drug's kinetic profile: area under the curve (AUC), maximal concentration (Cmax), time at which the maximal concentration occurs (tmax) and half-life time (t1/2). Several methods have been proposed to estimate these PK parameters. A first method relies on interpolating between observed concentrations. The interpolation method is often chosen linear. This method is simple and fast. Another method relies on compartmental modelling. In this case, nonlinear methods are used to estimate parameters of a chosen compartmental model. This method provides generally good results. However, if the data are sparse and noisy, two difficulties can arise with this method. The first one is related to the choice of the suitable compartmental model given the small number of data available in preclinical experiment for instance. Second, nonlinear methods can fail to converge. Much work has been done recently to circumvent these problems (J. Pharmacokinet. Pharmacodyn. 2007; 34:229,249, Stat. Comput., to appear, Biometrical J., to appear, ESAIM P&S 2004; 8:115,131). In this paper, we propose a Bayesian nonparametric model based on P-splines. This method provides good PK parameters estimation, whatever be the number of available observations and the level of noise in the data. Simulations show that the proposed method provides better PK parameters estimations than the interpolation method, both in terms of bias and precision. The Bayesian nonparametric method provides also better AUC and t1/2 estimations than a correctly specified compartmental model, whereas this last method performs better in tmax and Cmax estimations. We extend the basic model to a hierarchical one that treats the case where we have concentrations from different subjects. We are then able to get individual PK parameter estimations. Finally, with Bayesian methods, we can get easily some uncertainty measures by obtaining credibility sets for each PK parameter. Copyright © 2008 John Wiley & Sons, Ltd. [source] Estimation of Pump Flow Rate and Abnormal Condition of Implantable Rotary Blood Pumps During Long-Term In Vivo StudyARTIFICIAL ORGANS, Issue 4 2000K. Nakata Abstract: The control system for an implantable rotary blood pump is not clearly defined. A detection system is considered to be necessary for pump flow monitoring and abnormal conditions such as back flow or a sucking phenomenon where the septum or left ventricle wall is sucked into the cannula, etc. The ultrasound flowmeter is durable and reliable but the control system should not be totally dependent on the flowmeter. If the flowmeter breaks, the rotary blood pumps have no control mechanism. Therefore, the authors suggest controlling the pumps by an intrinsic parameter. One left ventricular assist device (LVAD) calf model was studied where the flow rate and waveform of the pump flow proved to identify the sucking phenomenon. Thus, the pump flow rate was calculated from the required power, motor speed, and heart rate. The value of the coefficient of determination (R2) between the measured and estimated pump flow rate was 0.796. To estimate this abnormal phenomenon, 2 methods were evaluated. One method was the total pressure head in which the pump flow rate and motor speed were estimated. During normal conditions the total pressure head is 79.5 ± 7.0 mm Hg whereas in the abnormal condition, it is 180.0 ± 2.8 mm Hg. There was a statistical difference (p < 0.01). Another method is using a current waveform. There is an association between the current and pump flow waves. The current was differentiated and squared to calculate the power of the differentiated current. The normal range of this value was 0.025 ± 0.029; the abnormal condition was 11.25 ± 15.13. There was a statistical difference (p < 0.01). The predicted flow estimation method and a sucking detection method were available from intrinsic parameters of the pump and need no sensors. These 2 methods are simple, yet effective and reliable control methods for a rotary blood pump. [source] Identification of occupational therapy clinical expertise: Decision-making characteristicsAUSTRALIAN OCCUPATIONAL THERAPY JOURNAL, Issue 3 2009Mehdi Rassafiani Background:,Experts are usually determined on the basis of length of experience, reputation, peer acknowledgement, and certification. While these characteristics are important they may, however, not be sufficient for this purpose. Another method for determining clinical expertise is to look at how individuals make decisions in their area of expertise. This study aims to identify clinician expertise on the basis of participants' decision performance and examines this in relation to their length of experience and type of decision-making. Methods:,The Cochran,Weiss,Shanteau (CWS) is a statistical method that can be used to examine individuals' expertise on the basis of how they discriminate between hypothetical cases and consistency in their decision-making. Participants comprised 18 occupational therapists, each with more than 5 years of experience working with children with cerebral palsy. They were required to make treatment judgements for 110 cases (20 of which were repeated) of children with cerebral palsy. The CWS was calculated for each participant. Results and conclusions:,Two groups of participants were identified on the basis of their CWS index , one with both high consistency in decision-making and the ability to discriminate between cases, the other with low consistency and poor discrimination. These two groups did not differ significantly on the basis of length of experience or work setting but did differ on the basis of intervention chosen and their type of decision-making. The CWS method seems to offer promise as a means of determining clinical expertise on the basis of clinical decision-making. Its application to the investigation of clinical reasoning and education is discussed. [source] Flow cytometry antibody screening using pooled red cells,CYTOMETRY, Issue 2 2010Dong Il Won Abstract Background: For red cell alloantibody screening, the column agglutination technique (CAT) is used extensively, and flow cytometry (FC) screening has recently been demonstrated to be accurate, rapid, and cost effective. We attempted to determine whether the high sensitivity of FC allows pooling of screening red cells, which is generally not an acceptable technique in CAT. Methods: For FC screening, a commercial two-cell screening panel was utilized for the preparation of individual cells (CSi), as well as pooled cells diluted 1 in 2 (CSp), and 1 in 3 (CS1/3). Another panel was pooled from 120 randomly selected group O donors (RSp). Results: Comparing the endpoint titrations of serial dilutions, CS1/3 was found to be one dilution, on the average, less sensitive than CSi. In 33 CAT-positive patient samples, the sensitivities of CSi and CSp did not differ significantly without polyethylene glycol (PEG) (30/33, 26/33, respectively, P = 0.125), although they did differ significantly with PEG (32/33, 25/33, respectively, P = 0.016). The percentages of reactive cells among the total cells from RSp were roughly proportional to the relevant antigen frequencies of the local donors. Conclusions: A trend toward reduced sensitivity was observed using pooled red cells, even via FC. Pooled cells from randomly selected group O donors may be employed as another method by which the characteristics of known antibodies might be assessed. © 2009 Clinical Cytometry Society [source] The use of self-expandable metallic stents for palliative treatment of inoperable esophageal cancerDISEASES OF THE ESOPHAGUS, Issue 1 2010A. Eroglu SUMMARY Most patients with esophageal carcinoma present in the advanced stage die from tumor invasion and widespread metastases. Because radical regimens are not appropriate for the majority of patients, and their expected survivals are as short as to be measured by months, the main aim of therapy is palliation with minimum morbidity and mortality. Among the palliative modalities are surgery, external radiotherapy or brachytherapy, dilatation, laser, photodynamic therapy, bipolar electrocoagulation tumor probe, and chemical ablation. The placement of self-expandable metallic stents is another method that improves dysphagia for these patients. In this study, the aim was to evaluate retrospectively the effectiveness of metallic stents deployed because of inoperable malignant esophageal stenosis and esophagotracheal fistulas. The results of 170 patients with 202 stents administered because of inoperable malignant esophageal stenosis and esophagorespiratory fistula between January 2000 and October 2008 at the Ataturk University, Department of Thoracic Surgery, were investigated. Despite epidemiological and clinical data, information regarding relief of dysphagia and quality of life were also examined. One hundred seventy patients with stents were between 28 and 91 years old (mean age 63.7 years ± 11.4 years). Ninety-seven were male and 73 were female. Stent indications were advanced tumors with distant metastasis (82 cases, 48.2%), unresectable tumors (51 cases, 30%), patients who cannot tolerate surgery or chemoradiotherapy (18 cases, 10.5%), local recurrence after primary therapy (1 case, 0.5%), esophagorespiratory fistulas from tumor or therapy (14 cases, 8.2%), and refusal of surgery (4 cases, 2.3%). Dysphagia scores evaluated by a modified Takita's grading system improved from 3.4 before the procedure to 2.6 afterward. The overall complication rate without chest pain was 31.7% (occurring in 64 cases). Mean survival was 177.7 days ± 59.3 days (2,993 days). Quality-of-life scores (The European Organization of Research and Treatment of Cancer QLQ C30) improved from 73 ± 10.3 (57,85) to 112 ± 12.6 (90,125). In therapy of malignant esophageal obstructions, metallic stents provide a significant improvement in dysphagia and require less frequent re-intervention according to other methods of dysphagia palliation such as dilatation, laser, and photodynamic therapy, nearly completely relieve esophagotracheal fistulas and improve quality of life to an important degree. [source] Microstructural Characterization of Lamellar Features in TiAl by FIB Imaging,ADVANCED ENGINEERING MATERIALS, Issue 6 2010Dennis Peter A novel experimental procedure is introduced to determine phase fractions and the distribution of individual phases of TiAl-based two-phase alloys using the focused ion beam (FIB) technique. Two , -titanium aluminide alloys with a fine-grained duplex and a nearly lamellar microstructure are examined. The special FIB-based preparation procedure results in high contrast ion beam-induced images for all investigated alloys and allows to quantify the phase contents easily by automated microstructural analysis. Fine two-phase structures, e.g. lamellar colonies in , -TiAl, can be imaged in high resolution with respect to different phases. To validate the FIB-derived data, we compare them to results obtained with another method to determine phase fractions, electron back-scatter diffraction (EBSD). This direct comparison shows that the FIB-based technique generally provides slightly higher ,2 -fractions, and thus helps to overcome the limited lateral resolution near grain boundaries and interfaces associated with the conventional EBSD approach. Our study demonstrates that the FIB-based technique is a simple, fast, and more exact way to determine high resolution microstructural characteristics with respect to different phase constitutions in two-phase TiAl alloys and other such materials with fine, lamellar microstructures. [source] On the estimation of fatigue life in notches differentiating the phases of crack initiation and propagationFATIGUE & FRACTURE OF ENGINEERING MATERIALS AND STRUCTURES, Issue 1 2010J. VÁZQUEZ ABSTRACT Over the last three decades, a variety of models have been developed in order to predict the life of components under fatigue. Some of the models are based on the definition of the fatigue process as a combination of the phases of crack initiation and crack propagation, considering component life as the sum of the duration of each phase. Other models consider only one of the phases; some consider only initiation while others only propagation, though in this case, from cracks with lengths in the order of the microstructural dimensions. This article will carry out a comparative analysis of the methods that consider life as the sum of the duration of both phases. In this same line, it proposes yet another method, which simulates crack growth according to damage theories. In analysing the behaviour of each model, this paper will describe various elements: the prediction that each of them produces regarding notched specimens submitted to testing, the advantages and inconveniences of each, and lastly, the possibilities of applying each of the models to more realistic geometries. [source] PEL: an unbiased method for estimating age-dependent genetic disease risk from pedigree data unselected for family historyGENETIC EPIDEMIOLOGY, Issue 5 2009F. Alarcon Abstract Providing valid risk estimates of a genetic disease with variable age of onset is a major challenge for prevention strategies. When data are obtained from pedigrees ascertained through affected individuals, an adjustment for ascertainment bias is necessary. This article focuses on ascertainment through at least one affected and presents an estimation method based on maximum likelihood, called the Proband's phenotype exclusion likelihood or PEL for estimating age-dependent penetrance using disease status and genotypic information of family members in pedigrees unselected for family history. We studied the properties of the PEL and compared with another method, the prospective likelihood, in terms of bias and efficiency in risk estimate. For that purpose, family samples were simulated under various disease risk models and under various ascertainment patterns. We showed that, whatever the genetic model and the ascertainment scheme, the PEL provided unbiased estimates, whereas the prospective likelihood exhibited some bias in a number of situations. As an illustration, we estimated the disease risk for transthyretin amyloid neuropathy from a French sample and a Portuguese sample and for BRCA1/2 associated breast cancer from a sample ascertained on early-onset breast cancer cases. Genet. Epidemiol. 33:379,385, 2009. © 2008 Wiley-Liss, Inc. [source] Generalization of belief and plausibility functions to fuzzy sets based on the sugeno integralINTERNATIONAL JOURNAL OF INTELLIGENT SYSTEMS, Issue 11 2007Chao-Ming Hwang Uncertainty has been treated in science for several decades. It always exists in real systems. Probability has been traditionally used in modeling uncertainty. Belief and plausibility functions based on the Dempster,Shafer theory (DST) become another method of measuring uncertainty, as they have been widely studied and applied in diverse areas. Conversely, a fuzzy set has been successfully used as the idea of partial memberships of multiple classes for the presentation of unsharp boundaries. It is well used as the representation of human knowledge in complex systems. Nowadays, there exist several generalizations of belief and plausibility functions to fuzzy sets in the literature. In this article, we propose a new generalization of belief and plausibility functions to fuzzy sets based on the Sugeno integral. We then make comparisons of the proposed generalization with some existing methods. The results show the effectiveness of the proposed generalization, especially for being able to catch more information about the change of fuzzy focal elements. © 2007 Wiley Periodicals, Inc. Int J Int Syst 22: 1215,1228, 2007. [source] Deterministic fallacies and model validationJOURNAL OF CHEMOMETRICS, Issue 3-4 2010Douglas M. Hawkins Abstract Stochastic settings differ from deterministic ones in many subtle ways, making it easy to slip into errors through applying deterministic thinking inappropriately. We suspect this is the cause of much of the disagreement about model validation. A further technical issue is a common misapplication of cross-validation, in which it is applied only partially, leading to incorrect results. Statistical theory and empirical investigation verify the efficacy of cross-validation when it is applied correctly. In settings where data are relatively scarce, cross-validation is attractive in that it makes the maximum possible use of all available information, at the cost of potentially substantial computation. The bootstrap is another method that makes full use of all available data for both model fitting and model validation, at a cost of substantially increased computation, and it shares many of the broad philosophical background of cross-validation. Increasingly, the computational cost of these methods is not a major concern, leading to the recommendation, in most circumstances, to use cross-validation or bootstrapping rather than the earlier standard method of splitting the available data into a learning and a testing portion. Copyright © 2010 John Wiley & Sons, Ltd. [source] Myth and reality: practical test system for the measurement of anti-DNA antibodies in the diagnosis of systemic lupus erythematosus (SLE)JOURNAL OF CLINICAL LABORATORY ANALYSIS, Issue 2 2010Laura J. McCloskey Abstract The myth persists that only the labor intensive Farr radioimmunoassay and Crithidia luciliae immunofluorescence (CL-IFA) are systemic lupus erythematosus (SLE)-specific tests. We compared them to ELISA with bacteriophage , DNA (EL-dsDNA) and denatured calf thymus DNA (EL-ssDNA). By percentile ranking, the specificity cut-off level was set both out of clinical context (SOCC) on 100 blood bank donors, and in clinical context (SICC) on 100 patients with either rheumatoid arthritis or scleroderma (50/50). Clinical sensitivity was calculated on 100 random SLE patients. At 95% SICC, the sensitivity of Farr, CL-IFA, EL-dsDNA, and EL-ssDNA was similar (95%CI): 76% (66,84), 76% (66,84), 63% (53,72), and 75% (65,83), respectively; 87% of the patients were positive by at least one method and 55%by all methods. At 99% SICC, the sensitivity was also similar (95% CI): 57% (47,67), 47% (37,57), 58% (47,67), and 43% (33,53), respectively. The areas under ROC curve were similar (95% CI) when patients were used as controls for specificity. At 99% SOCC, EL-ssDNA identified 89% positive, 2 negative but positive by another method at 95% SICC, and 9 negative (i.e. 89/2/9), followed by CL-IFA (80/6/14), Farr (76/12/12), and EL-dsDNA (64/23/13). Thus, at relatively low cost and easy automation, under the same conditions of specificity, the two ELISA tests combined were at least as good, if not superior, to CL-IFA or Farr: they showed similar clinical sensitivity and also identified more patients with anti-DNA antibodies. J. Clin. Lab. Anal. 24:77,84, 2010. © 2010 Wiley-Liss, Inc. [source] Controlling the mass action of ,-synuclein in Parkinson's diseaseJOURNAL OF NEUROCHEMISTRY, Issue 2 2008Changyoun Kim Abstract Parkinson's disease (PD) is an age-related neurodegenerative disease with unknown etiology. Growing evidence from genetic, pathologic, animal modeling, and biochemical studies strongly support the theory that abnormal aggregation of ,-synuclein plays a critical role in the pathogenesis of PD. Protein aggregation is an alternative folding process that competes with the native folding pathway. Whether or not a protein is subject to the aggregation process is determined by the concentration of the protein as well as thermodynamic properties inherent to each polypeptide. An increase in cellular concentration of ,-synuclein has been associated with the disease in both familial and sporadic forms of PD. Thus, maintenance of the intraneuronal steady state levels of ,-synuclein below the critical concentration is a key challenge neuronal cells are facing. Expression of the ,-synuclein gene is under the control of environmental factors and aging, the two best-established risk factors for PD. Studies also suggest that the degradation of this protein is mediated by proteasomal and autophagic pathways, which are two mechanisms that are related to the pathogenesis of PD. Recently, vesicle-mediated exocytosis has been suggested as a novel mechanism for disposal of neuronal ,-synuclein. Relocalization of the protein to specific compartments may be another method for increasing its local concentration. Regulation of the neuronal steady state levels of ,-synuclein has significant implications in the development of PD, and understanding the mechanism may disclose potential therapeutic targets for PD and other related diseases. [source] Abstracts of the 8th Meeting of the Italian Peripheral Nerve Study Group: 79JOURNAL OF THE PERIPHERAL NERVOUS SYSTEM, Issue 1 2003U Del Carro Peripheral neuropathy is one of the most common secondary complications of diabetes mellitus, causing severe and prolonged morbidity. However, clinical and experimental studies have reported that careful glucose control may prevent, stabilize, and/or reverse neuropathy and other chronic diabetic complications. Unfortunately, insulin therapy does not prevent the development or progression of chronic lesions in the vessels, kidneys, eyes, or nerves of the diabetic patient. There is great interest in investigating other forms of endocrine replacement therapy, such as transplantation of the pancreas or of the islets of Langerhans (IT). Diabetic polyneuropathy (DP) evolution is characterized by progressive demyelination and axonal loss and is manifested by signs and symptoms on physical examination and abnormalities in nerve conduction studies (NCS). NCS provide reliable, noninvasive, objective measures of peripheral nerve function and constitute the most important technique for the evaluation of the severity of DP in clinical trials. Several research groups have demonstrated that skin biopsy with measurement of intraepidermal nerve fiber density is another method minimally invasive and repeatable that provides direct pathologic evidence of axonal damage in diabetic neuropathy. Fifty-one consecutive IDDM patients with or without end stage renal disease were enrolled at the moment of islet (Is), kidney (KD), kidney-pancreas (KP) or kidney-islet (KI) transplantation. Patients underwent skin biopsy punch, neurologic examination and neurophysiological investigation. Particularly, 20 pts underwent KP tx, 16 KD tx, 10 islet tx and 5 KI. The patients were comparable for duration of diabetes, dialysis (when present), age, lipid profile. In half of the patients a follow-up of 2 years has been reached. After KP tx, and partially with KI, a complete normalization of glycometabolic control has been achieved, with statistically lower HbA1c in comparison with KD group (KP = 6.2; 0.1% vs. KD = 8.4; 0.5%; p < 0.01). In the KI/Is group, a long-term restoration of islet endocrine function has been achieved, with insulin independence. When this has been lost, a persistent secretion of C-peptide was shown for a long period of time. This was correlated with a global improvement quality of life and vascular structure. Preliminary results will be presented. [source] Corrosion behaviour of tool steels in tannic acidsMATERIALS AND CORROSION/WERKSTOFFE UND KORROSION, Issue 3 2009H. Winkelmann Abstract It is well known that cutting knifes in the wood industry often suffer from corrosion. Investigations showed that the corrosiveness of different wood types is responsible for a major part of the damage, and that different woods have a different corrosive impact. It is revealed that tannin, a water-soluble acid, which can be found in all woods in different concentrations, is the most aggressive acid contained in the wood, and so it is responsible for the main part of the corrosive attack. In view of the above, the ability of different cold-work steels to resist corrosion caused by tannic acid has been investigated. Often corrosion is measured by the mass loss of the sample divided by the surface of the sample under certain conditions during a fixed period of time. One problem with this method is that there is also a weight gain caused by oxidation or by other side reactions at the samples surface. So in some cases the weight of the sample even increases during the testing time, which makes the quantification of the corrosion impossible with this method. Due to the reasons already mentioned, another method was used to quantify the test results. This method is based on inductive coupled plasma,optical emission spectral analyses (ICP-OES), where the released Fe is quantified. The results of the corrosion resistant tests get correlated to the microstructure and the elemental composition of the analysed cold-work steels. The present investigations improve the understanding of important material parameters to enhance the corrosion resistance against tannin. It is revealed that the higher the primary carbide concentration is the more Cr or other passivating elements are necessary in the matrix to show a good protection against corrosion by tannin. Three materials with different elemental compositions have been investigated, and for one of those materials the influence of different heat treatments was also analysed. The investigations could show that annealing parameters and freeze-cycle processing (FCP) have less impact on the corrosion resistance to tannin than elemental composition and austenitising temperature. [source] Thermal histories of IVA iron meteorites from transmission electron microscopy of the cloudy zone microstructureMETEORITICS & PLANETARY SCIENCE, Issue 3 2009J. I. GOLDSTEIN Thin sections for TEM analysis were produced by a focused ion beam instrument. Use of the TEM allowed us to avoid potential artifacts which may be introduced during specimen preparation for SEM analysis of high Ni particles <30 nm in size and to identify microchemical and microstructural changes due to the effects of shock induced reheating. No cloudy zone was observed in five of the eight moderately to highly shocked (>13 GPa) IVA irons that were examined in the TEM. Shock induced reheating has allowed for diffusion from 20 nm to 400 nm across kamacite/taenite boundaries, recrystallization of kamacite, and the formation, in Jamestown, of taenite grain boundaries. In the eleven IVA irons with cloudy zone microstructures, the size of the high-Ni particles in the cloudy zone increases directly with increasing bulk Ni content. Our data and the inverse correlation between cooling rate and high-Ni particle size for irons and stony-irons show that IVA cooling rates at 350-200 °C are inversely correlated with bulk Ni concentration and vary by a factor of about 15. This cooling rate variation is incompatible with cooling in a metallic core that was insulated with a silicate mantle, but is compatible with cooling in a metallic body of radius 150 ± 50 km. The widths of the tetrataenite regions next to the cloudy zone correlate directly with high-Ni particle size providing another method to measure low temperature cooling rates. [source] Whistle: another method of induction of pediatric anesthesiaPEDIATRIC ANESTHESIA, Issue 9 2007Rajesh Mahajan MD No abstract is available for this article. [source] The making of fetal surgeryPRENATAL DIAGNOSIS, Issue 7 2010Jan A. Deprest Abstract Fetal diagnosis prompts the question for fetal therapy in highly selected cases. Some conditions are suitable for in utero surgical intervention. This paper reviews historically important steps in the development of fetal surgery. The first invasive fetal intervention in 1963 was an intra-uterine blood transfusion. It took another 20 years to understand the pathophysiology of other candidate fetal conditions and to develop safe anaesthetic and surgical techniques before the team at the University of California at San Francisco performed its first urinary diversion through hysterotomy. This procedure would be abandoned as renal and pulmonary function could be just as effectively salvaged by ultrasound-guided insertion of a bladder shunt. Fetoscopy is another method for direct access to the feto-placental unit. It was historically used for fetal visualisation to guide biopsies or for vascular access but was also abandoned following the introduction of high-resolution ultrasound. Miniaturisation revived fetoscopy in the 1990s, since when it has been successfully used to operate on the placenta and umbilical cord. Today, it is also used in fetuses with congenital diaphragmatic hernia (CDH), in whom lung growth is triggered by percutaneous tracheal occlusion. It can also be used to diagnose and treat urinary obstruction. Many fetal interventions remain investigational but for a number of conditions randomised trials have established the role of in utero surgery, making fetal surgery a clinical reality in a number of fetal therapy programmes. The safety of fetal surgery is such that even non-lethal conditions, such as myelomeningocoele repair, are at this moment considered a potential indication. This, as well as fetal intervention for CDH, is currently being investigated in randomised trials. Copyright © 2010 John Wiley & Sons, Ltd. [source] Use of ,dual protection' and other combinations of contraceptive methods in AustraliaAUSTRALIAN AND NEW ZEALAND JOURNAL OF PUBLIC HEALTH, Issue 6 2007Nick Parr Abstract Objective: To examine the demographic profiles of contraceptive users in Australia, paying particular attention to the use of condoms with other methods. Method: Data from a specific section on contraceptive use in the 2005 Wave 5 of the nationwide, longitudinal Household Income and Labour Dynamics in Australia (HILDA) were analysed. The section was restricted to 2,221 women aged 18-44; women were excluded if they were pregnant or subfecund, or if they or their partner had been sterilised. Results: Two-thirds of respondents were using contraception, including more than 15% who indicated use of more than one method. The contraceptive pill (39%) was the most widely used method, followed by the condom (28%). Women using sex-related methods were more likely to be using more than one method. More than one-quarter of pill users (28%) were using condoms as well. The combination of pill and condom was significantly associated with age, being a student, and country of birth. Less than 3% of women reported using rhythm methods and of these two-thirds were using another method. Conclusions: Dual protection provided by the combination of the condom with the pill or other methods has become an important factor in the prevention of sexually transmitted infections and unwanted pregnancies, but continuing education on dual protection and better access to treatment is still necessary for both men and women, particularly among at-risk groups. [source] Dehydrohalogenation in Alpha-Functionalized Poly- p -xylylenes,CHEMICAL VAPOR DEPOSITION, Issue 4 2006P. Carrow Abstract Poly(p -xylylene) or parylene has been around for more than a half a century. It is typically deposited by the Gorham method from [2.2] paracyclophane. However, another method is via alpha-derivatives of p -xylene. Both poly(,-bromo- p -xylylene) and poly(,-chloro- p -xylylene) have been successfully deposited by this route through predominately HBr or HCl dehydrohalogenation gas-phase reactions. In the study reported here we synthesize ,,,,,-tribromo- p -xylene and ,-bromo-,,,,,-dichloro- p -xylene as CVD precursors to yield ,,,- and ,,,,-dihalogenated poly(p -xylylene)s to try to convert them, via post-deposition annealing, to poly(phenylene ethynylene) (PPE). PPE and its intermediate poly(phenylene vinylene) (PPV), have potentially better thermal and oxidative properties, and in addition they are both photoluminescent. The as-deposited and annealed thin films have been characterized by Rutherford backscattering spectrometry (RBS), infrared spectroscopy, and UV-vis spectrophotometry, and electrically tested by dielectric constant, bias-temperature stress (BTS), and leakage current. It is found that the thin films crystallizes concurrent with the formation of PPV and possibly converts to PPE but has much residual chlorine and bromine. However, PPV exhibits excellent stability in contact with copper and is more thermally stable than poly(p -xylylene). 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