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The purpose of this study is to develop a novel breast abnormality detection system by utilizing the potential of infrared breast thermography (IBT) in early breast abnormality detection. Since the temperature distributions are different in normal and abnormal thermograms and hot thermal patches are visible in abnormal thermograms, the abnormal thermograms possess more complex information than the normal thermograms. Here, the proposed method exploits the presence of hot thermal patches and vascular changes by using the power law transformation for pre-processing and singular value decomposition to characterize the thermal patches. The extracted singular values are found to be statistically significant (p?<?0.001) in breast abnormality detection. The discriminability of the singular values is evaluated by using seven different classifiers incorporating tenfold cross-validations, where the thermograms of the Department of Biotechnology-Tripura University-Jadavpur University (DBT-TU-JU) and Database of Mastology Research (DMR) databases are used. In DMR database, the highest classification accuracy of 98.00% with the area under the ROC curve (AUC) of 0.9862 is achieved with the support vector machine using polynomial kernel. The same for the DBT-TU-JU database is 92.50% with AUC of 0.9680 using the same classifier. The comparison of the proposed method with the other reported methods concludes that the proposed method outperforms the other existing methods as well as other traditional feature sets used in IBT based breast abnormality detection. Moreover, by using Rank1 and Rank2 singular values, a breast abnormality grading (BAG) index has also been developed for grading the thermograms based on their degree of abnormality.  相似文献   
94.
The aims of this study were to evaluate the weekly and annual cumulative radiofrequency-electromagnetic field (RF-EMF) exposure attributed to mobile phone (MP) use, and assess whether a novel app (Quanta Monitor?) could be employed in a small human sample to characterise the RF-EMF exposures associated with the use of MPs. Ten participants provided their two months’ daily objective data on their MP exposures (i.e. transmitted and received power densities) attributed to different modes of MP usage such as cellular calls, cellular data and Wi-Fi. The results demonstrated that total transmitted power density (cellular phone calls, data and Wi-Fi surfing) could be many orders of magnitude higher than that from the total received power density. Of the total transmitted power density, cellular data use contributed the largest portion. Our study showed that Quanta Monitor? could be employed in prospective assessment of exposures to MPs in epidemiological studies.  相似文献   
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Aim

To provide a systematic review of the existing theory, framework, systems and instruments for tracing and evaluating quality in rural health services.

Subjects and methods

We searched six electronic databases up to March 2016. Observational studies of quality assessment of rural health services using theoretical models were included. Ekman’s scale was used to evaluate the quality of the included studies.

Results

A total of 18 studies, published between 2001 and 2015, met the inclusion criteria. The corresponding authors for most of them (7, 44%) are from Chinese institutions and three (3, 17%) from Australian institutions. Five studies (28%) focused on township hospitals. Primary health care quality was reported in five studies (28%), followed by clinical service in four (22%). More than half of the studies (61%) were considered of high quality, and the remainder was of moderate quality. These studies applied 16 theoretical systems, including the model/pattern (4, 25%), method/tool (7, 44%) and framework of the theory (5, 31%). Most of the theoretical models (14, 88%) obtained positive observations. In addition, the conceptual model (6, 36%) and TOPSIS method (2, 13%) were more frequently reported.

Conclusion

Although most of the current studies were considered to have high-quality and positive results, there were limitations in the number of publications and research on theoretical systems. The lacks of unified standards and comprehensive evaluation are important issues that need to be pointed out and resolved.
  相似文献   
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Intersectionality theory calls for the understanding of race/ethnicity, sex/gender and class as interlinked. Intersectional analysis can contribute to public health both through furthering understanding of power dynamics causing health disparities, and by pointing to heterogeneities within, and overlap between, social groups. The latter places the usefulness of social categories in public health under scrutiny. Drawing on McCall we relate the first approach to categorical and the second to anti-categorical intersectionality. Here, we juxtapose the categorical approach with traditional between-group risk calculations (e.g. odds ratios) and the anti-categorical approach with the statistical concept of discriminatory accuracy (DA), which is routinely used to evaluate disease markers in epidemiology. To demonstrate the salience of this distinction, we use the example of racial/ethnic identification and its value for predicting influenza vaccine uptake compared to other conceivable ways of organizing attention to social differentiation. We analyzed data on 56,434 adults who responded to the NHFS. We performed logistic regressions to estimate odds ratios and computed the area under the receiver operating characteristic curve (AU-ROC) to measure DA. Above age, the most informative variables were education and household poverty status, with race/ethnicity providing minor additional information. Our results show that the practical value of standard racial/ethnic categories for making inferences about vaccination status is questionable, because of the high degree of outcome variability within, and overlap between, categories. We argue that, reminiscent of potential tension between categorical and anti-categorical perspectives, between-group risk should be placed and understood in relationship to measures of DA, to avoid the lure of misguided individual-level interventions.  相似文献   
100.

Purpose

The number of single households has increased worldwide with middle-aged people in such households indicating the highest increase. However, there is a lack of studies on the topic. This study estimated the quality of life (QOL) by household type for middle-aged Korean adults.

Methods

We used the Korea National Health and Nutrition Examination Survey data from 2007 to 2015. QOL was analyzed using EQ-5D 3-level, and demographic and health-related variables were included as confounders. The households were divided into single household, married couple without child, other one-generation, married couple with child, single parent with child, other two-generation, and three-generation. Logistic regression using level, strata, and sample weight of data was performed based on average QOL.

Results

This study included 18,147 responders aged 45–64 years, with single households constituting 5.7%. Single households having average or less QOL were 48.4%, with men and women constituting 40.1 and 53.3%, respectively. After adjusting socioeconomic factors and health-related factors, the odds ratio (OR) of single households was 1.375 (95% CI 1.122–1.684) compared to the three-generation group. According to the sex, the OR of single households with men was higher (OR 1.552, 95% CI 1.121–2.149). However, no significance was found in women.

Conclusions

The study results revealed that middle-aged people in single households had low QOL than those in multi-person households. The trend was significantly observable in men than in women. Because middle-aged adults might transform into elderly with low QOL, program development and social support for middle-aged adults in single households should be provided.
  相似文献   
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