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Greater Accuracy (greater + accuracy)
Selected AbstractsQuantification of algal endosymbionts (Symbiodinium) in coral tissue using real-time PCRMOLECULAR ECOLOGY RESOURCES, Issue 1 2009J. C. MIEOG Abstract Understanding the flexibility of the endosymbioses between scleractinian corals and single-cell algae of the genus Symbiodinium will provide valuable insights into the future of coral reefs. Here, a real-time polymerase chain reaction (PCR) assay is presented to accurately determine the cell densities of Symbiodinium clades C and D in the scleractinian coral Acropora millepora, which can be extended to other coral,symbiont associations in the future. The assay targets single- to low-copy genes of the actin family of both the coral host and algal symbiont. Symbiont densities are expressed as the ratio of Symbiodinium cells to each host cell (S/H ratio, error within 30%), but can also be normalized to coral surface area. Greater accuracy in estimating ratios of associations involving multiple clades is achieved compared with previous real-time PCR assays based on high-copy ribosomal DNA loci (error within an order of magnitude). Healthy adult A. millepora containing ~1.4 × 106 zooxanthellae per cm2 (as determined by haemocytometer counts) had S/H ratios of c. 0.15, i.e. ~15 symbiont cells per 100 host cells. In severely bleached colonies, this ratio decreased to less than 0.005. Because of its capacity to accurately determine both densities and ratios of multiple symbionts within one sample, the assay will open the door for novel research into the mechanisms of symbiont shuffling and switching. [source] Use of linked loci as individuals or haplotypes for marker-assisted breed assignmentANIMAL GENETICS, Issue 1 2008A. Stella Summary The objective of this study was to use simulation to evaluate the benefits of considering haplotypes of loci when linked single nucleotide polymorphisms are used for breed assignment. Three breeds of 10 000 females each were simulated under eight scenarios that differed according to the number of generations separating the breeds, size of breed founder populations and recombination rate between linked loci. Molecular genotypes consisted of 20 groups of three linked loci each. Breed assignment was performed in the final generation and was based on the frequency method. Haplotypes were reconstructed using the expectation,maximization algorithm. Accuracy of breed assignment was based on the frequency of correct breed assignment. Assignment accuracy increased as more genotypes (loci or haplotypes) were considered and more animals were used to estimate genotypic frequencies within breed. For most scenarios, use of haplotypes yielded equal or greater accuracies than when loci were considered independent. The advantage of haplotypes tended to increase as linkage disequilibrium between adjacent loci increased. The greatest advantage for using haplotypes was observed when recombination rate was low (0.001), breeds were separated by few generations (100), and a relatively large number of founder animals (110) was used to form new breeds. In this situation, 90% accuracy of breed assignment was achieved using nine to 14 haplotypes (i.e. 27,42 loci) depending on breed, vs. 39,57 individual loci. [source] Clustering revealed in high-resolution simulations and visualization of multi-resolution features in fluid,particle modelsCONCURRENCY AND COMPUTATION: PRACTICE & EXPERIENCE, Issue 2 2003Krzysztof Boryczko Abstract Simulating natural phenomena at greater accuracy results in an explosive growth of data. Large-scale simulations with particles currently involve ensembles consisting of between 106 and 109 particles, which cover 105,106 time steps. Thus, the data files produced in a single run can reach from tens of gigabytes to hundreds of terabytes. This data bank allows one to reconstruct the spatio-temporal evolution of both the particle system as a whole and each particle separately. Realistically, for one to look at a large data set at full resolution at all times is not possible and, in fact, not necessary. We have developed an agglomerative clustering technique, based on the concept of a mutual nearest neighbor (MNN). This procedure can be easily adapted for efficient visualization of extremely large data sets from simulations with particles at various resolution levels. We present the parallel algorithm for MNN clustering and its timings on the IBM SP and SGI/Origin 3800 multiprocessor systems for up to 16 million fluid particles. The high efficiency obtained is mainly due to the similarity in the algorithmic structure of MNN clustering and particle methods. We show various examples drawn from MNN applications in visualization and analysis of the order of a few hundred gigabytes of data from discrete particle simulations, using dissipative particle dynamics and fluid particle models. Because data clustering is the first step in this concept extraction procedure, we may employ this clustering procedure to many other fields such as data mining, earthquake events and stellar populations in nebula clusters. Copyright © 2003 John Wiley & Sons, Ltd. [source] Eye remember you two: gaze direction modulates face recognition in a developmental studyDEVELOPMENTAL SCIENCE, Issue 5 2006Alastair D. Smith The effects of gaze direction on memory for faces were studied in children from three different age groups (6,7, 8,9, and 10,11 years old) using a computerized version of a task devised by Hood, Macrae, Cole-Davies and Dias (2003). Participants were presented with a sequence of faces in an encoding phase, and were then required to judge which faces they had previously encountered in a surprise two-alternative forced-choice recognition test. In one condition, stimulus eye gaze was either direct or deviated at the viewing phase, and eyes were closed at the test phase. In another condition, stimulus eyes were closed at the viewing phase, with either direct or deviated gaze at the test phase. Modulation of gaze direction affected hit rates, with participants demonstrating greater accuracy for direct gaze targets compared to deviated gaze targets in both conditions. Reaction times (RT) to correctly recognized stimuli were faster for direct gaze stimuli at the viewing phase, but not at the test phase. The age group of participants differentially affected these measures: there was a greater hit rate advantage for direct gaze stimuli in older children, although RTs were less affected by age. These findings suggest that while the facilitation of face recognition by gaze direction is robust across encoding and recognition stages, the efficiency of the process is affected by the stage at which gaze is modulated. [source] Accuracy and precision of the continuous underway fish egg sampler (CUFES) and bongo nets: a comparison of three species of temperate fishFISHERIES OCEANOGRAPHY, Issue 6 2005P. PEPIN Abstract We examine the accuracy and precision of the continuous underway fish egg sampler (CUFES) relative to bongo nets based on the catch ratio of Atlantic cod (Gadus morhua), American plaice (Hippoglossoides platessoides), and cunner (Tautogolabrus adspersus). We derived expectation of catch ratios based on the application of a one-dimensional model of the vertical distribution of fish eggs applied to cod and on prior data on egg vertical distribution. Samples were collected in May and August 2001, two periods when the vertical structure of the water column differed substantially. Stationary CUFES collections did not yield significant differences in accuracy or precision relative to the underway CUFES. In May, when there was relatively little stratification, the CUFES-to-bongo catch ratio of cod and plaice eggs was well within expectations based on model predictions. In August, the CUFES-to-bongo catch ratios of cod and cunner were higher than expected. Generally, there was a greater proportion of early stage eggs in bongo than in CUFES samples, with the strongest differences in American plaice. The replicate variance of the CUFES was ,25 times greater than that of the bongo nets, probably because of the large volumes sampled by bongo nets relative to the CUFES. Given that the CUFES provides greater accuracy in mapping but lower precision than bongo nets, multiple sampling gears may be the most effective method for surveying fish eggs of pelagic and demersal species. [source] Assessing the sources and magnitude of diurnal nitrate variability in the San Joaquin River (California) with an in situ optical nitrate sensor and dual nitrate isotopesFRESHWATER BIOLOGY, Issue 2 2009BRIAN A. PELLERIN Summary 1.,We investigated diurnal nitrate (NO3,) concentration variability in the San Joaquin River using an in situ optical NO3, sensor and discrete sampling during a 5-day summer period characterized by high algal productivity. Dual NO3, isotopes (,15NNO3 and ,18ONO3) and dissolved oxygen isotopes (,18ODO) were measured over 2 days to assess NO3, sources and biogeochemical controls over diurnal time-scales. 2.,Concerted temporal patterns of dissolved oxygen (DO) concentrations and ,18ODO were consistent with photosynthesis, respiration and atmospheric O2 exchange, providing evidence of diurnal biological processes independent of river discharge. 3.,Surface water NO3, concentrations varied by up to 22% over a single diurnal cycle and up to 31% over the 5-day study, but did not reveal concerted diurnal patterns at a frequency comparable to DO concentrations. The decoupling of ,15NNO3 and ,18ONO3 isotopes suggests that algal assimilation and denitrification are not major processes controlling diurnal NO3, variability in the San Joaquin River during the study. The lack of a clear explanation for NO3, variability likely reflects a combination of riverine biological processes and time-varying physical transport of NO3, from upstream agricultural drains to the mainstem San Joaquin River. 4.,The application of an in situ optical NO3, sensor along with discrete samples provides a view into the fine temporal structure of hydrochemical data and may allow for greater accuracy in pollution assessment. [source] Neural system interactions underlying human transitive inferenceHIPPOCAMPUS, Issue 8 2010Sandra N. Moses Abstract Human problem solving relies on multiple strategies supported by dynamic neural network interactions. The transitive inference (TI) problem solving task can be accomplished by the extraction of relations among stimuli or by responding to reinforcement histories of items using associative learning. Relational and associative strategies are assumed to rely on the hippocampus and caudate nucleus, respectively; which compete to control behavior. However, we found that increased recruitment of both systems in TI is correlated with greater accuracy and awareness, and reduced associative responding to single items. Contrary to prior assumptions, the hippocampus and caudate interact cooperatively to facilitate successful TI. We suggest that the dynamics of the relationship between the hippocampus and caudate depends critically upon task demands. © 2010 Wiley-Liss, Inc. [source] Analyzing brain networks with PCA and conditional Granger causalityHUMAN BRAIN MAPPING, Issue 7 2009Zhenyu Zhou Abstract Identifying directional influences in anatomical and functional circuits presents one of the greatest challenges for understanding neural computations in the brain. Granger causality mapping (GCM) derived from vector autoregressive models of data has been employed for this purpose, revealing complex temporal and spatial dynamics underlying cognitive processes. However, the traditional GCM methods are computationally expensive, as signals from thousands of voxels within selected regions of interest (ROIs) are individually processed, and being based on pairwise Granger causality, they lack the ability to distinguish direct from indirect connectivity among brain regions. In this work a new algorithm called PCA based conditional GCM is proposed to overcome these problems. The algorithm implements the following two procedures: (i) dimensionality reduction in ROIs of interest with principle component analysis (PCA), and (ii) estimation of the direct causal influences in local brain networks, using conditional Granger causality. Our results show that the proposed method achieves greater accuracy in detecting network connectivity than the commonly used pairwise Granger causality method. Furthermore, the use of PCA components in conjunction with conditional GCM greatly reduces the computational cost relative to the use of individual voxel time series. Hum Brain Mapp, 2009. © 2008 Wiley-Liss, Inc. [source] Narcissism, confidence, and risk attitudeJOURNAL OF BEHAVIORAL DECISION MAKING, Issue 4 2004W. Keith Campbell Abstract The present research addresses whether narcissists are more overconfident than others and whether this overconfidence leads to deficits in decision making. In Study 1, narcissism predicted overconfidence. This was attributable to narcissists' greater confidence despite no greater accuracy. In Study 2, participants were offered fair bets on their answers. Narcissists lost significantly more points in this betting task than non-narcissists, due both to their greater overconfidence and greater willingness to bet. Finally, in Study 3, narcissists' predictions of future performance were based on performance expectations rather than actual performance. This research extends the literature on betting on knowledge to the important personality dimension of narcissism. Copyright © 2004 John Wiley & Sons, Ltd. [source] Image analysis systems for the detection of disseminated breast cancer cells on bone-marrow cytospinsJOURNAL OF CLINICAL LABORATORY ANALYSIS, Issue 3 2005Sven Becker Abstract We assessed the accuracy of automated cell imaging systems when compared to manual evaluation of cytospin slides in determining the presence of cytokeratin-positive, disseminated breast cancer cells in bone marrow aspirates. A total of 298 cytospin slides of bone marrow aspirates were first evaluated by individual screening by one expert immunocytologist. Subsequently, all 298 slides were evaluated by the Automated Cell Imaging System (ACIS) by ChromaVisionÔ. Two separate analysis cycles were performed using ACIS. The results of the two ACIS analysis cycles were almost identical: in 293 out of 298 samples (98.3%), identical numbers of disseminated breast cancer cells were detected. In the remaining five samples (1.7%), the result of the two ACIS analysis cycles differed by only one tumor cell. By using the manual technique, 120 cytospin samples were found to be positive. ACIS was able to detect additional tumor cells in 64 cases. Not once did ACIS miss tumor cells when compared to the manual technique. Using ACIS, we were able to determine the bone marrow status of patients with nonmetastatic breast cancer faster, with greater accuracy, and with greater reproducibility than with the manual technique. J. Clin. Lab. Anal. 19:115,119, 2005. © 2005 Wiley-Liss, Inc. [source] Effect of Two Types of Control Questions and Two Question Formats on the Outcomes of Polygraph Examinations,JOURNAL OF FORENSIC SCIENCES, Issue 4 2008Frank Horvath Ph.D. Abstract:, Two major variations of polygraph "Control Question" testing, the Zone Comparison (ZoC) and the Modified General Question Test (MGQT) were evaluated. Within each, the type of control question, Exclusive or "time bar" (e.g., "Before you were 21, did you ever...") and Nonexclusive or "no time bar"(e.g., "Did you ever,.?") was manipulated in a mock theft scenario, with 80 male and 40 female subjects randomly assigned to be either innocent or guilty. Polygraphic data collected by experienced field examiners were numerically scored by an evaluator blind to all aspects of the study. Decision accuracy was not related to the type of procedure (ZoC/MGQT) used or the subject's sex. Accuracy was significantly related to the type of control question [,2(2) = 11.46, p = 0.003; ,c = 0.29]. Nonexclusive control questions produced greater accuracy than Exclusive control questions on both innocent and guilty subjects. These results and subjects' self-reports support the general "theory" on which control question (CQ) testing is based. The need for better empirical support of accepted dogma and current field practices is strongly indicated by these findings. [source] Bringing Everyday Mind Reading Into Everyday Life: Assessing Empathic Accuracy With Daily Diary DataJOURNAL OF PERSONALITY, Issue 5 2010Maryhope Howland ABSTRACT Individual differences in empathic accuracy (EA) can be assessed using daily diary methods as a complement to more commonly used lab-based behavioral observations. Using electronic dyadic diaries, we distinguished among elements of EA (i.e., accuracy in levels, scatter, and pattern, regarding both positive and negative moods) and examined them as phenomena at both the day and the person level. In a 3-week diary study of cohabiting partners, we found support for differentiating these elements. The proposed indices reflect differing aspects of accuracy, with considerable similarity among same-valenced accuracy indices. Overall there was greater accuracy regarding negative target moods than positive target moods. These methods and findings take the phenomenon of "everyday mindreading" (Ickes, 2003) into everyday life. We conclude by discussing empathic accuracies as a family of capacities for, or tendencies toward, accurate interpersonal sensitivity. Members of this family may have distinct associations with the perceiver's, target's, and relationship's well-being. [source] Inconsistencies Between Actual and Estimated Blood Alcohol Concentrations in a Field Study of College Students: Do Students Really Know How Much They Drink?ALCOHOLISM, Issue 9 2005Courtney L. Kraus Background: Alcohol use by college students is commonly measured through the use of surveys. The validity of such data hinge on the assumption that students are aware of how much alcohol they actually consume. Recent studies call this assumption into question. Students tend to overestimate the appropriate sizes of standard drinks, suggesting that they might underestimate how much alcohol they consume. If this is true, then students' actual blood alcohol concentrations (BACs) should be higher than BACs estimated based on self-report data. The present study examined this issue Methods: Breathalyzer readings and self-reported drinking data were collected from 152 college students during the fall of 2004. Estimated BACs were calculated by means of a standard formula, and the relation between actual and estimated BACs was examined. Factors contributing to discrepancies between the two values were identified Results: Estimated BAC levels were significantly higher, not lower, than breath BAC measures. The accuracy of estimated BACs decreased as the number of drinks and amount of time spent drinking increased. Being male and drinking only beer predicted greater accuracy of estimated BACs Conclusions: Although laboratory data suggest that students underestimate how much they drink, the hypothesis was not supported by data collected in the field. It appears that students might actually overestimate rather than underestimate their levels of consumption when surveyed in the midst of a night of drinking. The findings corroborate observations made by other researchers and suggest that the findings of laboratory studies on college drinking do not necessarily extend to real-world settings. [source] Correlating sideband patterns with powder patterns for accurate determination of chemical shift parameters in solid-state NMRMAGNETIC RESONANCE IN CHEMISTRY, Issue 10 2008M. S. Ironside Abstract Powder patterns and sideband patterns have different strengths when it comes to using them to determine chemical shift parameters. Here, we show that chemical shift parameters can be determined with high accuracy by analysing the correlation pattern from a 2D experiment which correlates a powder pattern in the indirect dimension with a sideband pattern in the direct dimension. The chemical shift parameters so determined have greater accuracy than those obtained by analysing a sideband or powder pattern alone, for the same signal-to-noise ratio. This method can be applied for both resolved correlation patterns and to cases where two components share similar isotropic chemical shifts. The methodology is demonstrated in this paper, both theoretically and experimentally, on the 31P signals of the bis-phosphonate drug, pamidronate. Copyright © 2008 John Wiley & Sons, Ltd. [source] The Relationship between Empathy and Estimates of Observed PainPAIN MEDICINE, Issue 2 2009A. D. Green MSc ABSTRACT Objective., Recent research suggests that higher scores on measures of empathy correlate with a stronger response to observed pain, as well as higher estimates of pain intensity. Little work to date has examined the impact of empathy on evaluations of different levels of expressed pain, or how empathy may alter the accuracy of interpreting these painful facial expressions. This study examines the role of empathy in rating the intensity of facial expressions of pain, and the accuracy of these ratings relative to self-reported pain. The potential mediating role of available pain cues or the moderating role of gender on this relationship are also examined. Methods., Undergraduate participants (observers, N = 130) were shown video clips of facial expressions of individuals from a cold presser pain task (senders), and then asked to estimate that pain experience. This estimate was compared with the video sender's actual pain ratings. Results., Higher empathy was associated with an overall increase in estimates of senders' pain, which was not mediated by video subject or participant gender or the duration of painful facial expressions. Further analyses revealed that high empathy was associated with greater accuracy in inferring pain on only one of three inferential accuracy indices. Conclusions., While observers with greater empathy may infer greater pain in senders, resulting in a smaller underestimation bias overall, they are not necessarily more accurate in estimating pain on any given stimuli. The importance of these potential differences in perceived pain for clinical assessment and interpersonal relationships are discussed. [source] Definitions of the phenotypic manifestations of sickle cell disease,AMERICAN JOURNAL OF HEMATOLOGY, Issue 1 2010Samir K. Ballas Sickle cell disease (SCD) is a pleiotropic genetic disorder of hemoglobin that has profound multiorgan effects. The low prevalence of SCD (,100,000/US) has limited progress in clinical, basic, and translational research. Lack of a large, readily accessible population for clinical studies has contributed to the absence of standard definitions and diagnostic criteria for the numerous complications of SCD and inadequate understanding of SCD pathophysiology. In 2005, the Comprehensive Sickle Cell Centers initiated a project to establish consensus definitions of the most frequently occurring complications. A group of clinicians and scientists with extensive expertise in research and treatment of SCD gathered to identify and categorize the most common complications. From this group, a formal writing team was formed that further reviewed the literature, sought specialist input, and produced definitions in a standard format. This article provides an overview of the process and describes 12 body system categories and the most prevalent or severe complications within these categories. A detailed Appendix provides standardized definitions for all complications identified within each system. This report proposes use of these definitions for studies of SCD complications, so future studies can be comparably robust and treatment efficacy measured. Use of these definitions will support greater accuracy in genotype,phenotype studies, thereby achieving a better understanding of SCD pathophysiology. This should nevertheless be viewed as a dynamic rather than final document; phenotype descriptions should be reevaluated and revised periodically to provide the most current standard definitions as etiologic factors are better understood, and new diagnostic options are developed. Am. J. Hematol. 2010. © 2009 Wiley-Liss, Inc. [source] Attitude of health-care providers toward childhood leukemia patients with different socio-economic status,PEDIATRIC BLOOD & CANCER, Issue 5 2008Saskia Mostert MD Abstract Background Treatment results differ significantly between poor and prosperous children with leukemia in Indonesia. The objective of this study was to determine whether parental socio-economic status influences beliefs, attitude, and behavior of health-care providers (hcp) treating childhood leukemia in Indonesia. Procedure A self-administered semi-structured questionnaire was filled in by 102 hcp (69 doctors, 28 nurses, 2 psychologists, 2 hematology technicians, 1 administrator). Results Most hcp (98%) asked parents about their financial situation. The decision to start treatment was influenced by parental socio-economic status (86%), motivation of parents (80%), and motivation of doctors (76%). Health-care providers stated that prosperous patients comply better with treatment (64%), doctors comply better with treatment for the prosperous (53%), most patients cannot afford to complete treatment (58%), less extensive explanations are given toward poor families (60%), and communication is impeded by differences in status (67%). When dealing with prosperous families a minority of hcp stated that they pay more attention (27%), work with greater accuracy (24%), take more interest (23%), and devote more time per visit (22%). Most hcp denied differences in the quality of medical care (93%) and the chances of cure (58%) between poor and prosperous patients. Conclusions Beliefs, attitude, and behavior of hcp toward poor versus prosperous patients appeared to differ. These differences may contribute to the immense drop-out rate and slight chances of survival among poor patients with leukemia in developing countries. Pediatr Blood Cancer 2008;50:1001,1005. © 2007 Wiley-Liss, Inc. [source] The Diamedica Draw-Over Vaporizer: a comparison of a new vaporizer with the Oxford Miniature VaporizerANAESTHESIA, Issue 1 2009W. A. English Summary The Diamedica Draw-Over Vaporizer (DDV) has been developed as an alternative to the Oxford Miniature Vaporizer (OMV). Both can function as draw-over or plenum vaporizers. The performances of these two vaporizers were compared under conditions simulating intermittent positive pressure ventilation (IPPV) and continuous flow (CF). Series 1 experiments were conducted with the vaporizers in water baths at 20, 25 and 30 °C. Vaporizers were tested at dial settings of 1,4% over a range of minute volumes (1.75,6 l.min,1) and flow rates (3,8 l.min,1). Series 2 experiments compared output of the vaporizers over time at ambient temperatures of 20, 25 and 30 °C. A minute volume of 6 l.min,1 (IPPV) and a gas flow of 8 l.min,1 (CF) were used with a vaporizer setting of 2%. Vapour concentrations were recorded at 5-min intervals. In series 1 IPPV experiments, the DDV vaporizer was more accurate, producing significantly fewer vapour concentrations 0.5% more than or less than setting (p = 0.013). The OMV tended to produce more favourable results under continuous flow (p = 0.42). In series 2 experiments, the accuracy of both vaporizers was similar but consistency of output over time was better for the DDV and consistency of output according to differences in ambient temperature was better for the DDV. The OMV produced more vapour concentrations that were markedly higher than dial setting, particularly at high ambient temperatures. The DDV is a suitable alternative to the OMV with some distinct advantages. These include a larger reservoir, tendency towards greater accuracy during IPPV and improved consistency of output. [source] Development of a parathyroid database in Melbourne and review of the last 50 casesANZ JOURNAL OF SURGERY, Issue 9 2004Meei J. Yeung Background: Minimally invasive parathyroidectomy (MIP) is only possible if preoperative localization studies accurately identify the abnormal parathyroid tissue. The aim of the present paper was to evaluate the accuracy of these studies in our geographical region and the consequences on MIP. Methods: A Filemaker Pro database was designed and a retrospective analysis was carried out on the last 50 parathyroidectomies. Results: There were a total of 49 patients who underwent parathyroidectomy; with one patient having two operations. Forty-nine preoperative ultrasound localization studies were performed. Ultrasound sensitivity of correct localization of abnormal parathyroids was 41% with a false positive rate of 25%. Twenty-two sestamibi scans identified 14 abnormal parathyroids. Sestamibi scanning had a sensitivity of 32% for correct localization and a false positive rate of 32%. There were 16 different radiologists or nuclear medicine physicians involved with the nuclear medicine scans, and 22 different radiologists involved in the preoperative ultrasound scans. Forty-seven patients were cured of hyperparathyroidism after a primary operation, with a total of 48 patients in all being cured following re-exploration. One patient was lost to follow up. The success of primary exploration was therefore 96% and following re-exploration this increased to 98%. Conclusion: We found preoperative localization studies to have low sensitivities and high false positive rates. To move successfully towards MIP, we need to identify a radiologist with a special interest in localization studies to achieve greater accuracy. [source] Comparison of 11 endogenous control genes for normalization of mRNA obtained from paraffin-embedded tissuesAPMIS, Issue 12 2009REKHA PAI Real-time reverse transcriptase PCR (RT-PCR) based assays are being increasingly used in characterization of gene expression. Good quality mRNA is an essential prerequisite for such assays. While fresh tissues provide quality mRNA, the same may not be true of tissues which are formalin-fixed and paraffin-embedded (FFPE). This emphasizes the need to identify a good endogenous control gene to normalize for differences in quality and RNA recovery. We attempted to characterize gene expression patterns of 11 commonly used endogenous control genes among 20 FFPE tissues (both neoplastic and normal). Pearson's coefficient of correlation was determined by comparing the expression of each gene against the mean expression of all other genes. ,2 microglobulin (,2M) and ,-actin (,A) (r = 0.95 and 0.94, respectively) were found to be stably expressed across all tissues. However, ,A had greater accuracy (2 × SD) than ,2M and therefore may be a better choice of an endogenous control for experiments that require normalization while using FFPE tissues. [source] Lay knowledge of eyewitness issues: A Canadian evaluationAPPLIED COGNITIVE PSYCHOLOGY, Issue 3 2009J. Don Read Lay opinions concerning eyewitness topics were surveyed in three community samples of juror-eligible participants in Canada. The scientific reliability of these topics had been previously evaluated by eyewitness experts. The first survey assessed participant responses to the identically worded expert items. Participants responded to many statements with greater accuracy than anticipated. Two subsequent surveys assessed the consistency of lay knowledge across variations in the directionality and wording of items and the provision of additional contextual information. Taken together, jury-eligible participants frequently responded to survey items in ways that closely resembled the responses of experts and suggested awareness and understanding of these topics at levels beyond those previously obtained. Further, the provision of contextual information increased response accuracy and reduced the frequencies of ,Don't Know' responses. Deficiencies in knowledge for 50% of the topics were also apparent; however, these topics were frequently those for which the experts themselves had not reached consensus. Copyright © 2008 John Wiley & Sons, Ltd. [source] Basis of metamemory judgments for text with multiple-choice, essay and recall tests,APPLIED COGNITIVE PSYCHOLOGY, Issue 2 2009Ruth H. Maki Accuracy of metamemory for text was compared for multiple-choice, essay and recall tests. Essay and recall tests were scored with Latent Semantic Analysis (LSA), number of correct idea units and number of word matches. Each measure was correlated with college students' predictions and posttest confidence judgments across texts to determine metamemory accuracy. Metamemory accuracy varied for different types of tests with multiple-choice tests generally producing greater accuracy than essay tests. However, metamemory accuracy for essay and recall tests depended on the measure used to score them. Number of correct idea units produced the highest metamemory accuracy, word matches produced an intermediate level, and LSA produced the lowest accuracy. Students used the quantity of output in their judgments, so performance measures that related most strongly to quantity matched judgments better than measures based on answer quality. The results are compatible with an accessibility account of judgments about performance on text. Copyright © 2008 John Wiley & Sons, Ltd. [source] A study investigating obstetricians' and gynaecologists' management of women requesting an intrauterine deviceAUSTRALIAN AND NEW ZEALAND JOURNAL OF OBSTETRICS AND GYNAECOLOGY, Issue 2 2010Kirsten I. BLACK Background:, Intrauterine methods including the copper intrauterine device (Cu-IUD) and the levonorgestrel intrauterine system (LNG-IUS) provide highly effective long-term reversible contraception. The reasons for relative low use of these methods in Australia compared to many European countries are not clear, but may in part relate to provider reluctance because of outdated knowledge about their safety and efficacy. Aims:, The aim of this study was to survey Australian Fellows of the Royal Australian and New Zealand College of Obstetricians and Gynaecologists about their knowledge of the risks, benefits and mechanisms of action of intrauterine methods. Methods:, In 2008, we undertook a cross-sectional survey of all Australian Fellows not registered as a subspecialist. The survey was mailed to 1050 practitioners and 701 were returned, comprising a response rate of 67%. Results:, Knowledge about the LNG-IUS was significantly better than for the Cu-IUD in terms of correct understanding about mechanism of action (89.3% vs. 30%; P < 0.001) and efficacy (63.2% vs. 33.5%; P < 0.001). According to the WHO, both methods are considered suitable for use in nulliparous women, yet only 39.1% of providers believed the Cu-IUD suitable compared to 69.4% for the LNG-IUS (P < 0.001). When responses were analysed according to time from graduation, many aspects of knowledge about these devices showed a linear trend, with greater accuracy in recent graduates (<10 years) compared with graduates of more than 30 years. Conclusion:, Both methods are highly effective, non-user dependent and reversible and deserve greater understanding and consideration for use by Australian practitioners and women. [source] Nonoverlapping Clusters: Approximate Distribution and Application to Molecular BiologyBIOMETRICS, Issue 2 2001Xiaoping Su Summary. An approach is developed for the screening of genomic sequence data to identify gene regulatory regions. This approach is based on deciding if putative transcription factor binding sites are clustered together to a greater extent than one would expect by chance. Given n events occurring on an interval of width L (L base pairs), an r:w cluster is defined as r+ 1 consecutive events all contained within a window of length wL. Accurate and easily computable approximations are derived for the distribution of the number of nonoverlapping r:w clusters under the model that the positions of the n events have a uniform distribution. Simulations demonstrate that these approximations have greater accuracy than existing methods. The approximation is applied to detect erythroid-specific regulatory regions in genomic DNA sequences, first in an artificial case where r is specified a priori and then as part of an exploratory approach. [source] Global Expression Profiling in Epileptogenesis: Does It Add to the Confusion?BRAIN PATHOLOGY, Issue 1 2010Yi Yuen Wang MBBS Abstract Since the inception of global gene expression profiling platforms in the mid-1990s, there has been a significant increase in publications of differentially expressed genes in the process of epileptogenesis. In particular for mesial temporal lobe epilepsy, the presence of a latency period between the first manifestation of seizures to chronic epilepsy provides the opportunity for therapeutic interventions at the molecular biology level. Using global expression profiling techniques, approximately 2000 genes have been published demonstrating differential expression in mesial temporal epilepsy. The majority of these changes, however, are specific to laboratory or experimental conditions with only 53 genes demonstrating changes in more than two publications. To this end, we review the current status of gene expression profiling in epileptogenesis and suggest standard guidelines to be followed for greater accuracy and reproducibility of results. [source] Scaling the structure,function relationship for clinical perimetryACTA OPHTHALMOLOGICA, Issue 4 2005Ronald S. Harwerth Abstract. Purpose:,The full ranges of glaucomatous visual field defects and retinal ganglion cell losses extend over several orders of magnitude and therefore an interpretation of the structure,function relationship for clinical perimetry requires scaling of both variables. However, the most appropriate scale has not been determined. The present study was undertaken to compare linear and logarithmic transformations, which have been proposed for correlating the perimetric defects and neural losses of glaucoma. Methods:,Perimetry, by behavioural testing, and retinal histology data were obtained from rhesus monkeys with significant visual field defects caused by experimental glaucoma. Ganglion cell densities were measured in histologic sections of retina that corresponded to specific perimetry test locations for the treated and control eyes. The linear (percentage) and logarithmic (decibel) relationships for sensitivity loss as a function of ganglion cell loss were analysed. Results:,With decibel scaling, visual sensitivity losses and ganglion cell densities were linearly correlated with high coefficients of determination (r2), although the parameters of the functions varied with eccentricity. The structure,function relationships expressed as linear percentage-loss functions were less systematic in two respects. Firstly, the relationship exhibited considerable scatter in the data for small losses in visual sensitivity and, secondly, visual sensitivity losses became saturated with larger losses in ganglion cell density. The parameters of the percentage-loss functions also varied with eccentricity, but the variation was less than for the decibel-loss functions. Conclusions:,Linear scaling of perimetric defects and ganglion cell losses might potentially improve the structure,function relationship for visual defects associated with small amounts of cell loss, but the usefulness of the relationship is limited because of the high variability in that range. With log,log co-ordinates, the structure,function relationship for clinical perimetry is relatively more accurate and precise for cell losses greater than about 3 dB. The comparatively greater accuracy and precision of decibel loss functions are a likely consequence of the logarithmic scale of stimulus intensities for perimetry measurements and because the relationship between visual sensitivity and the number of neural detectors is a form of probability summation. [source] Australian Cancer Network Clinical Practice Guidelines for the Management of ocular and periocular Melanoma: an evidence-based literature analysisCLINICAL & EXPERIMENTAL OPHTHALMOLOGY, Issue 7 2008Simon E Skalicky MBBS Abstract Background:, With recent advances in the diagnosis and management of ocular and periocular melanoma, many of which are based on results from randomized control trials, there is an increasing need for an evidence-based review of the literature for the Australasian population. The Australian Cancer Network has recently redeveloped the evidence-based Clinical Practice Guidelines for the Management of Melanoma, including a chapter on ocular melanoma. These are the first evidence-based guidelines on ocular melanoma to be created by the Australian Cancer Network. Methods:, The primary research questions were formed and a detailed literature search was undertaken. Each relevant article was assessed and graded I,IV according to the level of evidence. Articles were grouped into bodies of evidence which were then assessed. Results:, A total of 107 relevant articles were identified and grouped into 12 bodies of evidence. Guidelines based on this analysis were formulated and graded. These are presented below. Conclusions:, The management of ocular melanoma has benefited from recent advances in imaging, molecular biology and cytogenetics, and tumours today are detected earlier and with greater accuracy than 25 years ago. With improved treatment ocular and periocular melanomas can be controlled locally, with good preservation of vision in many patients. However, there remains no cure for metastatic disease. [source] | ||||||||||||||||||||||