973 resultados para STANDARD AUTOMATED PERIMETRY


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A system that can automatically detect nodules within lung images may assist expert radiologists in interpreting the abnormal patterns as nodules in 2D CT lung images. A system is presented that can automatically identify nodules of various sizes within lung images. The pattern classification method is employed to develop the proposed system. A random forest ensemble classifier is formed consisting of many weak learners that can grow decision trees. The forest selects the decision that has the most votes. The developed system consists of two random forest classifiers connected in a series fashion. A subset of CT lung images from the LIDC database is employed. It consists of 5721 images to train and test the system. There are 411 images that contained expert- radiologists identified nodules. Training sets consisting of nodule, non-nodule, and false-detection patterns are constructed. A collection of test images are also built. The first classifier is developed to detect all nodules. The second classifier is developed to eliminate the false detections produced by the first classifier. According to the experimental results, a true positive rate of 100%, and false positive rate of 1.4 per lung image are achieved.

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The central bearded dragon (Pogona vitticeps) is a medium-sized lizard that is common in semiarid habitats in Australia and that potentially is at risk of fenitrothion exposure from use of the chemical in plague locust control. We examined the effects of single sublethal doses of this organophosphate (OP; low dose = 2.0 mg/kg; high dose = 20 mg/kg; control = vehicle alone) on lizard thermal preference, standard metabolic rate, and prey-capture ability. We also measured activities of plasma total cholinesterase (ChE) and acetylcholinesterase before and at 0, 2, 8, 24, 120, and 504 h after OP dosing. Predose plasma total ChE activity differed significantly between sexes and averaged 0.66 ± 0.06 and 0.45 ± 0.06 μmol/min/ml for males and females, respectively. Approximately 75% of total ChE activity was attributable to butyrylcholinesterase. Peak ChE inhibition reached 19% 2 h after OP ingestion in the low-dose group, and 68% 8 h after ingestion in high-dose animals. Neither OP doses significantly affected diurnal body temperature, standard metabolic rate, or feeding rate. Plasma total ChE levels remained substantially depressed up to 21 d after dosing in the high-dose group, making this species a useful long-term biomonitor of OP exposure in its habitat.

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Objectives: Individual clinical interviews are typically viewed as the “gold standard” when diagnosing major depressive disorder (MDD) and when examining the validity of self-rated questionnaires. However, this approach may be problematic with older people, who are known to underreport depressive symptomatology. This study examined the effect of including an informant interview on prevalence estimations of MDD in an aged-care sample.

Design: The results of an individual clinical interview for MDD were compared with those obtained when an informant interview was incorporated into the assessment. Results from each diagnostic approach were compared with scores on a self-rated depression instrument.

Setting: Low-level aged-care residential facilities in Melbourne (equivalent to “residential homes,” “homes for the elderly,” or “assisted living facilities” in other countries).

Participants: One hundred and sixty-eight aged-care residents (mean age: 84.68 years; SD: 6.16 years) with normal cognitive functioning.

Measurements: Individual clinical interviews were conducted using the Structured Clinical Interview for Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition Axis I Disorders. This interview was modified for use with staff informants. Self-reported depression was measured using the Geriatric Depression Scale-15 (GDS-15).

Results: The estimated point prevalence of MDD rose from 16% to 22% by including an informant clinical interview in the diagnostic procedure. Overall, 27% of depressed residents failed to disclose symptoms in the clinical interview. The concordance of the GDS-15 with a diagnosis of MDD was substantially lower when an informant source was included in the diagnostic procedure.

Conclusion: Individual interviews and self-report questionnaires may be insufficient to detect depression among older adults. This study supports the use of an informant interview as an adjunct when diagnosing MDD among cognitively intact aged-care residents.

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Low-sodium Dietary Approaches to Stop Hypertension (DASH) diets are base producing but restrict red meat without clear justification. We hypothesized that a vitality diet (VD), a low-sodium DASH-type diet with a low dietary acid load containing 6 servings of 100 g cooked lean red meat per week, would be more effective in reducing blood pressure (BP) compared with a higher acid load reference healthy diet (RHD) based on general dietary guidelines to reduce fat intake and increase intake of breads and cereals. A randomized, parallel dietary intervention study was conducted to compare the BP-lowering effect of these 2 diets in postmenopausal women with high/normal BP. Women were randomly assigned to follow either VD or RHD for 14 weeks. Home BP was measured daily with an automated BP monitor under standard conditions. Of 111 women commencing the study, 95 completed (46 VD, 49 RHD). Systolic BP (SBP) throughout the intervention was lower in the VD group compared to the RHD group (repeated-measures analysis of variance time by diet, P = .04), such that at the end of the study, the VD had a fall of SBP by 5.6 ± 1.3 mm Hg (mean ± SEM) compared with a fall of 2.7 ± 1.0 mm Hg in the RHD (group difference, P = .08). When only those taking antihypertensive medications were assessed, the VD (n = 17) had a significant fall of 6.5 ± 2.5 mm Hg SBP (P = .02) and 4.6 ± 1.4 mm Hg diastolic BP (P = .005) after 14 weeks, and their BP was lower than that of the RHD group (n = 18) throughout the study (P < .05). We concluded that a low-sodium DASH diet with a low dietary acid load, which also included lean red meat on most days of the week, was effective in reducing BP in older women, particularly in those taking antihypertensive medications.

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Fabric pilling is a serious problem for the apparel industry. Resistance to pilling is normally tested by simulated accelerated wear and manual assessment of degree of pilling based on a visual comparison of the sample to a set of test images. A number of automated systems based on image analysis have been developed. The authors propose new methods of image analysis based on the two-dimensional wavelet transform to objectively measure the pilling intensity in sample images. Initial work employed the detail coefficients of the two-dimensional discrete wavelet transform (2DDWT) as a measure of the pilling intensity of woven/knitted fabrics.

This method is shown to be robust to image translation and brightness variation. Using the approximation coefficients of the 2DDWT, the method is extended to non-woven pilling image sets. Wavelet texture analysis (WTA) combined with principal components analysis are shown to produce a richer texture description of pilling for analysis and classification. Finally, employing the two-dimensional dual-tree complex wavelet transform as the basis for the WTA feature vector is shown to produce good automated classification on a range of standard pilling image sets.

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The reaction of tris(2,2’-bipyridyl)ruthenium(III) (Ru(bipy) 33+) with various analytes to generate chemiluminescence has been well documented. This investigation sought to undertake a chemiluminometic study of the reactions of Ru(bipy) 33+ with selected Papaver Somniferum alkaloids and specifically synthesised phenethylamines. The investigation, based on a kinetic study, primarily addressed the effect of varying reaction conditions (pH) on Ru(bipy) 33+ chemiluminescence production. To monitor these reactions, a batch chemiluminometer was specifically designed, fabricated and automated to conduct an extensive study on the selected compounds of interest. The instrumentation incorporated a custom built reaction cell and comprised an ‘on-line’ sample preparation system with which calibration standards could be automatically prepared. The instrumentation provided both time-independent (peak area) and time-dependent (kinetic profile) information. A novel approach to the stabilisation of Ru(bipy) 33+ as a chemiluminescencent reagent was also investigated and a recirculating system was employed with the batch chemiluminometer to provide a stable supply of Ru(bipy) 33+. Codeine, thebaine and 6-methoxy-codeine were the Papaver Somniferum alkaloids selected for this study and several N-methylated and N,N-dimethylated phenethylamines and methoxy-substituted phenetheylamines were also synthesised to investigate the affect of pH on the chemiluminescence emission efficiency. The versatility of the batch chemiluminometer facilitated the kinetic study of numerous analytes over a broad pH range. The exemplary performance of the chemiluminometer as an analytical instrument, was demonstrated by the calibration functions, based on peak area data, which exhibited excellent linearity and sensitivity. The estimated detection limits (3s) for the selected alkaloids were in the range 2 x 10-9 M to 7 x 10-9 at pH 5.0 and above, which compared favourably to detection limits for the same compounds determined using FIA. Relative standard deviations (n=5) for peak areas ranged between 1% to 5% with a mean of 3.1% for all calibration standards above 2.5 x 10-8 M. Correlation between concentration and peak area, irrespective of pH and analyte was excellent, with all but two calibration functions having r-squared values greater than 0.990. The analytical figures of merit exemplified the precision and robustness of the reagent delivery and ‘on-line’ sample preparation, as well as the sensitivity of the system. The employment of the chemiluminometer for the measurement of total chemiluminescence emission (peak area) was in itself a feasible analytical technique, which generated highly reproducible and consistent data. Excellent analytical figures of merit, based on peak area, were similarly achieved for the phenethylamines. The effects of analyte structure on chemiluminescence activity was also investigated for the alkaloids and the phenethylamines. Subtle structural variations between the three alkaloids resulted in either a moderately reduced or enhanced total emission that was two or three fold difference only. A significant difference in reaction kinetics was observed between thebaine and codeine/6-methoxy-codeine, which was dependent upon pH. The time-dependent data, namely the observed rate constants for the initial rise in intensity and for the subsequent decay rate, were obtained by fitting a mathematical function (based on the postulated reaction mechanism) to the raw data. The determination of these rate constants for chemiluminescence reactions highlighted the feasibility for utilising such measurements for quantitative analytical applications. The kinetic data were used to discriminate between analyte responses in order to determine the concentrations of individual analytes in a binary mixture. A preliminary, multi-component investigation performed on a binary mixture of codeine and 6-methoxy-codeine (1:1) successfully determined the concentrations of these individual components using such rate constant measurements. Consequently, variations in kinetics resulted in a significant difference between the relative chemiluminescence response based on peak area measurements and the relative response base on peak height measurements obtained using FIA. With regards to the observed reactivity of secondary amines and tertiary amines, chemiluminescence peak area determinations confirmed the vital role of pH on reaction efficiency, which was governed by structural features and kinetics. The tertiary amines investigated generally produced a greater emission under acidic conditions than the corresponding secondary amines. However, the measured chemiluminescence responses were highly dependent upon pH, with similar peak areas obtained for both amine groups under slightly alkaline conditions.

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Background Self-management is seen as a primary mechanism to support the optimization of care for people with chronic diseases such as symptomatic vascular disease. There are no established and evidence-based stroke-specific chronic disease self-management programs. Our aim is to evaluate whether a stroke-specific program is safe and feasible as part of a Phase II randomized-controlled clinical trial.
Methods Stroke survivors are recruited from a variety of sources including: hospital stroke services, local paper advertisements, Stroke South Australia newsletter (volunteer peer support organization), Divisions of General Practice, and community service providers across Adelaide, South Australia. Subjects are invited to participate in a multi-center, single-blind, randomized, controlled trial. Eligible participants are randomized to either;
standard care,
standard care plus a six week generic chronic condition self-management group education program, or,
standard care plus an eight week stroke specific self-management education group program.
Interventions are conducted after discharge from hospital. Participants are assessed at baseline, immediate post intervention and six months.
Study Outcomes The primary outcome measures determine study feasibility and safety, measuring, recruitment, participation, compliance and adverse events.
Secondary outcomes include:
• positive and active engagement in life measured by the Health Education Impact Questionnaire,
• improvements in quality of life measured by the Assessment of Quality of Life instrument,
• improvements in mood measured by the Irritability, Depression and Anxiety Scale,
• health resource utilization measured by a participant held diary and safety.

Conclusion The results of this study will determine whether a definitive Phase III efficacy trial is justified.

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What does the around-the-clock economic activity mean for workers' health? Despite the fact that non-standard work accounts for an increasing share of the job opportunities, relatively little is known about the potential consequences for health and the existing evidence is ambiguous. In this paper I examine the associations between non-standard job schedules and workers' physical and mental health outcomes using longitudinal data from the Household, Income and Labour Dynamics in Australia (HILDA). Specifically, the four health indicators considered are self-rated health and the SF-36 health indices for general health, mental health and physical functioning. Overall results generally suggest a negative relationship between non-standard work schedules and better health for both males and females. Regarding the statistical significance and magnitudes of the associations, however, we observe apparent differences between males and females. Among females, most of the coefficients in all models are statistically insignificant, which implies very small magnitudes in terms of the correlation between non-standard working hours and health. These results apply uniformly to all health measures investigated. Among males, on the other hand, the negative relationship is more noticeable for self-rated health, general health and physical functioning than for mental health. The pooled OLS and random effects coefficients are usually larger in magnitude and more significant than the fixed effects parameters. Nonetheless, even the more significant coefficients do not imply large effects in absolute terms.

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This study presents some implications of recent policy moves to enhance the harmonization of financial reporting and disclosure by adopting international financial reporting standards. In particular the impact on small organizations that do not participate in capital markets is considered. The results of a survey of practitioners indicate a perception that the non-capital market sector is likely to be significantly affected by additional reporting burden that convergence with international financial reporting standards imposes. On the whole the results show there was concern that the traditional users of the financial reports of organizations who do not participate in capital markets, would have limited if any, use for financial reports that conformed to international financial reporting standards, The results of this study have implications for nations such as Malaysia and New Zealand, which are currently engaging in the differential reporting debate.