982 resultados para change detection, visione stereo, background difference


Relevância:

30.00% 30.00%

Publicador:

Resumo:

Soluble fibres, such as guar gum, promote and wheat bran or methylcellulose protect from chemically induced colon carcinogenesis, relative to the effect of a fibre-free diet in rats. Mechanisms are poorly understood. Whereas all fibres are trophic to the colonic epithelium, the heterogeneity of effects on carcinogenesis may reflect different effects on the total number of crypts and, therefore, the size of the stem cell population. This study aimed to assess this hypothesis. Sprague–Dawley rats were fed one of fibre-free diets with or without 10% wheat bran, methylcellulose or guar gum for 4 weeks. The distal colons were stained with methylene blue and quantified for the number and density of crypts using an image analysis system. Epithelial proliferative kinetics was measured stathmokinetically. Methodology for quantifying crypts was valid and reproducible. Rats fed a fibre-free diet had atrophic distal colon, as shown by a decrease in crypt column height and a lower mitotic index. Fibre supplementation prevented the atrophy and was associated with crypt mouth areas that were 30–60% larger than those in the fibre-free group (P < 0.001, ANOVA), with the methylcellulose group being the largest (1.16 µm2). The crypt density of the fibre-free group was 16–19% greater than those in fibre fed groups (P + 0.006), due to the smaller size of the crypts. However, there was no difference in the total number of crypts across the four dietary groups (P > 0.1). Distal colons in all of the dietary groups contained ~105 crypts. In conclusion, although variation in the amount or type of dietary fibre exerts heterogeneous effects on the growth of the colonic epithelium and on colon carcinogenesis, the total number of crypts in the distal colon remains constant. It is, therefore, unlikely that fibres influence carcinogenic events by altering the size of the stem cell population.

Relevância:

30.00% 30.00%

Publicador:

Resumo:

Lung nodule refers to lung tissue abnormalities that may become cancerous. An automated system that detects nodules of common sizes within lung images is developed. It consists of acquisition, pre-processing, background removal, nodule detection, and false positives reduction. The system can assist expert radiologists in their decision making.

Relevância:

30.00% 30.00%

Publicador:

Resumo:

The introduction of ninhydrin treatment as a chemical technique for the visualisation of latent fingermarks on porous surfaces revolutionised approaches to forensic fingermark examination. Since then, a range of amino acid sensitive reagents has been developed and such compounds are in widespread use by law enforcement agencies worldwide. This paper reviews the development and use of these reagents for the detection of latent fingermarks on porous surfaces. A brief overview is provided, including an historical background, forensic significance, and a general approach to the development of latent fingermarks on porous surfaces. This is followed by a discussion of specific amino acid sensitive treatments.

Relevância:

30.00% 30.00%

Publicador:

Resumo:

For people living with a disability, enablers such as assistive technologies, environmental modifications and personal care can make the difference between living fully and merely existing. This article is written from the standpoints of people with disabilities and professionals in one Australian State who found their government and service system to be a constraining rather than an enabling force. It presents two key components of policy and practice change in the area of assistive technology: challenging understandings of disability, assistive technology, and the desired life outcomes that assistive technology contributes to; and building a public evidence base through consumer-focussed research. In short, government funding of assistive technology needs to move beyond a limited focus on functional needs and take responsibility for fully equipping people to live the lives they aspire to.

Relevância:

30.00% 30.00%

Publicador:

Resumo:

In this paper, we present our preliminary studies into naphthoquinones as novel reagents for the detection of latent fingermarks on paper. Latent fingermarks deposited on paper substrates were treated with solutions of selected naphthoquinones in ethyl acetate/HFE-7100, with subsequent heating. The selected compounds were 1,4-dihydroxy-2-naphthoic acid, 1,2-naphthoquinone-4-sulfonate, 2-methoxy-1,4-naphthoquinone and 2-methyl-1,4-naphthoquinone. All of the tested compounds yielded purple-brown visible fingermarks, which also exhibited photoluminescence when illuminated with a high intensity filtered light source at 555nm and viewed through red goggles. Indirect heat using an oven at 150 ◦C for 1 h was found to be superior to direct heat with an iron, which while providing faster development lead to increased levels of background colouration. Luminescence spectrophotometry revealed differences in photoluminescence characteristics for fingermarks developed with the different naphthoquinones, with excitation over the range 530–590 nm. Luminescence spectrophotometry of developed lysine, glycine and serine spots on paper was used to confirm that the naphthoquinones were reacting with amino acids in the latent fingermark.

Relevância:

30.00% 30.00%

Publicador:

Resumo:

In this paper, a novel bipolar time-spread (TS) echo hiding based watermarking method is proposed for stereo audio signals, to overcome the low robustness problem in the traditional TS echo hiding method. At the embedding, echo signals with opposite polarities are added to both channels of the host audio signal. This improves the imperceptibility of the watermarking scheme, since added watermarks have similar effects in both channels. Then decoding part is developed, in order to improve the robustness of the watermarking scheme against common attacks. Since these novel embedding and decoding methods utilize the advantage of two channels in stereo audio signals, it significantly reduces the interference of host signal at watermark extraction which is the main reason for error detection in the traditional TS echo hiding based watermarking under closed-loop attack. The effectiveness of the proposed watermarking scheme is theoretically analyzed and verified by simulations under common attacks. The proposed echo hiding method outperforms conventional TS echo hiding based watermarking when their perceptual qualities are similar.

Relevância:

30.00% 30.00%

Publicador:

Resumo:

Background : We aimed to determine the role of skeletal muscle mitochondrial ATP production rate (MAPR) in relation to exercise tolerance after resistance training (RT) in chronic heart failure (CHF).

Methods and Results : Thirteen CHF patients (New York Heart Association functional class 2.3 ± 0.5; Left ventricular ejection fraction 26 ± 8%; age 70 ± 8 years) underwent testing for peak total body oxygen consumption (VO2peak), and resting vastus lateralis muscle biopsy. Patients were then randomly allocated to 11 weeks of RT (n = 7), or continuance of usual care (C; n = 6), after which testing was repeated. Muscle samples were analyzed for MAPR, metabolic enzyme activity, and capillary density. VO2peak and MAPR in the presence of the pyruvate and malate (P+M) substrate combination, representing carbohydrate metabolism, increased in RT (P < .05) and decreased in C (P < .05), with a significant difference between groups (VO2peak, P = .005; MAPR, P = .03). There was a strong correlation between the change in MAPR and the change in peak total body oxygen consumption (VO2peak) over the study (r = 0.875; P < .0001), the change in MAPR accounting for 70% of the change in VO2peak.

Conclusions : These findings suggest that mitochondrial ATP production is a major determinant of aerobic capacity in CHF patients and can be favorably altered by muscle strengthening exercise.

Relevância:

30.00% 30.00%

Publicador:

Resumo:

Background: Brain glutathione levels are decreased in schizophrenia, a disorder that often is chronic and refractory to treatment. N-acetyl cysteine (NAC) increases brain glutathione in rodents. This study was conducted to evaluate the safety and effectiveness of oral NAC (1 g orally twice daily [b.i.d.]) as an add-on to maintenance medication for the treatment of chronic schizophrenia over a 24-week period.

Methods:
A randomized, multicenter, double-blind, placebo-controlled study. The primary readout was change from baseline on the Positive and Negative Symptoms Scale (PANSS) and its components. Secondary readouts included the Clinical Global Impression (CGI) Severity and Improvement scales, as well as general functioning and extrapyramidal rating scales. Changes following a 4-week treatment discontinuation were evaluated. One hundred forty people with chronic schizophrenia on maintenance antipsychotic medication were randomized; 84 completed treatment.

Results: Intent-to-treat analysis revealed that subjects treated with NAC improved more than placebo-treated subjects over the study period in PANSS total [5.97 (10.44, 1.51), p .009], PANSS negative [mean difference 1.83 (95% confidence interval: 3.33, .32), p .018], and PANSS general [2.79 (5.38, .20), p .035], CGI-Severity (CGI-S) [.26 (.44,.08), p .004], and CGI-Improvement (CGI-I) [.22 (.41, .03), p .025] scores. No significant change on the PANSS positive subscale was seen. N-acetyl cysteine treatment also was associated with an improvement in akathisia (p .022). Effect sizes at end point were consistent with moderate benefits.

Conclusions: These data suggest that adjunctive NAC has potential as a safe and moderately effective augmentation strategy for chronic schizophrenia.

Relevância:

30.00% 30.00%

Publicador:

Resumo:

Recent data from the Red List of the International Union for the Conservation of Nature show that 1240 of the world’s estimated 10 027 species of birds (12.4%) are listed as threatened (Hoffmann et al. 2010). Globally, many more are ‘declining’ in conservation status. In Europe, much attention has been given to the marked decline in the abundance and distributional extent of farmland birds associated with the intensification of agricultural production (Fuller et al. 1995; Donald et al. 2001). Recent analyses suggest woodland species alsomaynowbe experiencing significant declines (e.g. Hewson et al. 2007). In the Americas, the declining status of neotropical migrants has motivated considerable research over the last 30 years (e.g. Terborgh 1989; Robinson and Wilcove 1994). In the tropics, narrowly endemic land birds have been identified as those species most at risk of decline globally in coming decades owing to projected changes in land-use (Jetz et al. 2007). Particular taxonomic groups also are experiencing marked declines. Migratory shorebirds, for example, which depend on key stop-over sites for refuelling during intercontinental migration, are particularly vulnerable to the degradation and destruction of these sites (Barter 2002; Rogers et al. 2010). Such widespread change among the world’s avifauna has profound implications for global biodiversity, ecosystem function and the provision of ecosystem services (Sekercioglu 2006).

Relevância:

30.00% 30.00%

Publicador:

Resumo:

The study of interactions between organic biomolecules and semiconducting surfaces is an important consideration for the design and fabrication of field-effect-transistor (FET) biosensor. This paper demonstrates DNA detection by employing a double-gate field effect transistor (DGFET). In addition, an investigation of sensitivity and signal to noise ratio (SNR) is carried out for different values of analyte concentration, buffer ion concentration, pH, reaction constant, etc. Sensitivity, which is indicated by the change of drain current, increases non-linearly after a specific value (∼1nM) of analyte concentration and decreases non-linearly with buffer ion concentration. However, sensitivity is linearly related to the fluidic gate voltage. The drain current has a significant effect on the positive surface group (-NH2) compared to the negative counterpart (-OH). Furthermore, the sensor has the same response at a particular value of pH (5.76) irrespective of the density of surface group, although it decreases with pH value. The signal to noise ratio is improved with higher analyte concentrations and receptor densities.

Relevância:

30.00% 30.00%

Publicador:

Resumo:

All Change is a country & western instrumental featuring rhythm guitar, lead banjo, rhythm banjo, fiddle and upright bass with a wooden barn echo.

Relevância:

30.00% 30.00%

Publicador:

Resumo:

All Change Loop is a country & western instrumental featuring rhythm guitar, lead banjo, rhythm banjo, fiddle and upright bass with a wooden barn echo.

Relevância:

30.00% 30.00%

Publicador:

Resumo:

All Change RG & B Loop is a country & western instrumental featuring rhythm guitar and upright bass with a wooden barn echo.

Relevância:

30.00% 30.00%

Publicador:

Resumo:

Video event detection is an effective way to automatically understand the semantic content of the video. However, due to the mismatch between low-level visual features and high-level semantics, the research of video event detection encounters a number of challenges, such as how to extract the suitable information from video, how to represent the event, how to build up reasoning mechanism to infer the event according to video information. In this paper, we propose a novel event detection method. The method detects the video event based on the semantic trajectory, which is a high-level semantic description of the moving object’s trajectory in the video. The proposed method consists of three phases to transform low-level visual features to middle-level raw trajectory information and then to high-level semantic trajectory information. Event reasoning is then carried out with the assistance of semantic trajectory information and background knowledge. Additionally, to release the users’ burden in manual event definition, a method is further proposed to automatically discover the event-related semantic trajectory pattern from the sample semantic trajectories. Furthermore, in order to effectively use the discovered semantic trajectory patterns, the associative classification-based event detection framework is adopted to discover the possibly occurred event. Empirical studies show our methods can effectively and efficiently detect video events.

Relevância:

30.00% 30.00%

Publicador:

Resumo:

A desirable property of any edge detector is that it be a projection in the mathematical sense, that is, that when it is applied to its own output it produces no further change. This report examines the behaviour of some conventional and some new operators when applied to line-drawings. The Marr-Hildreth and some gradient operators are among the conventional operators examined. Also a class of energy feature detectors is explored. It is shown that the energy feature detector is a true projection and does not proliferate edges when applied to a line-drawing, whereas several of the conventional operators do.