Digital variance angiography allows about 70% decrease of DSA-related radiation exposure in lower limb X-ray angiography

Our aim was to investigate whether the previously observed higher contrast-to-noise ratio (CNR) and better image quality of Digital Variance Angiography (DVA) - compared to Digital Subtraction Angiography (DSA) - can be used to reduce radiation exposure in lower limb X-ray angiography. This prospective study enrolled 30 peripheral artery disease patients (mean ± SD age 70 ± 8 years) undergoing diagnostic angiography. In all patients, both normal (1.2 µGy/frame; 100%) and low-dose (0.36 µGy/frame; 30%) protocols were used for the acquisition of images in three anatomical regions (abdominal, femoral, crural). The CNR of DSA and DVA images were calculated, and the visual quality was evaluated by seven specialists using a 5-grade Likert scale. For investigating non-inferiority, the difference of low-dose DVA and normal dose DSA scores (DVA30-DSA100) was analyzed. DVA produced two- to three-fold CNR and significantly higher visual score than DSA. DVA30 proved to be superior to DSA100 in the crural region (difference 0.25 ± 0.07, p < 0.001), and there was no significant difference in the femoral (− 0.08 ± 0.06, p = 0.435) and abdominal (− 0.10 ± 0.09, p = 0.350) regions. Our data show that DVA allows about 70% reduction of DSA-related radiation exposure in lower limb X-ray angiography, providing a potential new radiation protection tool for the patients and the medical staff.

Superimposed gratings induce diverse response patterns of gamma oscillations in primary visual cortex

Stimulus-dependence of gamma oscillations (GAMMA, 30–90 Hz) has not been fully understood, but it is important for revealing neural mechanisms and functions of GAMMA. Here, we recorded spiking activity (MUA) and the local field potential (LFP), driven by a variety of plaids (generated by two superimposed gratings orthogonal to each other and with different contrast combinations), in the primary visual cortex of anesthetized cats. We found two distinct narrow-band GAMMAs in the LFPs and a variety of response patterns to plaids. Similar to MUA, most response patterns showed that the second grating suppressed GAMMAs driven by the first one. However, there is only a weak site-by-site correlation between cross-orientation interactions in GAMMAs and those in MUAs. We developed a normalization model that could unify the response patterns of both GAMMAs and MUAs. Interestingly, compared with MUAs, the GAMMAs demonstrated a wider range of model parameters and more diverse response patterns to plaids. Further analysis revealed that normalization parameters for high GAMMA, but not those for low GAMMA, were significantly correlated with the discrepancy of spatial frequency between stimulus and sites’ preferences. Consistent with these findings, normalization parameters and diversity of high GAMMA exhibited a clear transition trend and region difference between area 17 to 18. Our results show that GAMMAs are also regulated in the form of normalization, but that the neural mechanisms for these normalizations might differ from those of spiking activity. Normalizations in different brain signals could be due to interactions of excitation and inhibitions at multiple stages in the visual system.

NEUTROSOPHIC TEXTURE-REGION DIFFERENCE-BASED FUZZY c-MEANS CLUSTERING OF ULTRASOUND TUMOR IMAGES

Owing to its cost effective and non-ionizing procedure, ultrasound imaging has become a primary tool for detection and diagnosis of breast tumors compared to mammography or biopsy. But the precise interpretation of the images obtained is limited due to the intensity inhomogeneties, speckle noise, low contrast, etc. present in the observed images. Also, tumors can appear in different echogenic patterns including visually challenging to detect isoechoic and slightly hypoechoic tumors, and distinguishing the tumor by means of intensity variations only will not suffice. Therefore it is important to preprocess the image to remove unwanted noise and variations, and thereby provide adequate enhancement to highlight the region of interest. In this paper, a segmentation method is proposed where the query images are clustered using fuzzy c-means clustering (FCM) after neutrosophic filtering and enhancement followed by extraction of textural and edge features through the use of Gabor and compass filters. In this work, Prewitt compass filters were implemented to capture the maximum region difference between the tumor and background. By using filters of different orientations, sufficient texture and edge information were able to be captured by using the combination of Gabor and compass filters, which can then aid in the accurate detection of isoechoic and hypoechoic tumors. The neutrosophic preprocessing implemented in this work models the ultrasound noise as combination of Gaussian and Rayleigh distributions, and shows better signal-to-noise ratio than traditionally modeling speckle as Gaussian alone. The proposed method gave an increase of 42.25%, 40.15%, 81.32% and 50.15% and a decrease of 95.83% compared to standard Otsu thresholding, an increase of 23.34%, 19.57%, 24.53% and 24.71% and a decrease of 91.81% compared to simple FCM and an increase of 37.89%, 44.64%, 35.86% and 48.11% and a decrease of 93.68% compared to active contour segmentation in structural similarity index, Jaccard index, Dice coefficient and accuracy and mean square error, respectively. On contrasting with recent learning-based methodologies for tumor segmentation, the proposed method gave comparable accuracy without the need for large training database and expensive graphical processing unit (GPU) computing capabilities.

A qualitative and quantitative evaluation of the Advancing Quality pay-for-performance programme in the NHS North West

BackgroundAdvancing Quality (AQ) is a voluntary programme providing financial incentives for improvement in the quality of care provided to NHS patients in the north-west of England.Objectives(1) To identify the impact of AQ on key stakeholders and clinical practice; (2) to assess its cost-effectiveness; (3) to identify key factors that assist or impede its successful implementation; and (4) to provide lessons for the wider implementation of pay-for-performance schemes across the NHS.DesignWe tested whether or not the financial incentives of AQ had an impact on mortality using two methods: a between-region difference-in-differences analysis comparing the North West region and the rest of England for the incentivised and non-incentivised conditions and a triple-difference analysis comparing performance on the incentivised conditions, as well as the non-incentivised conditions, in the North West region and the rest of England. A cost-effectiveness analysis of AQ based on the first 18 months of the programme was also undertaken. We used interviews and observation to explore how and why changes occurred.ResultsRisk-adjusted mortality rates for all three of the conditions we studied (pneumonia, heart failure and myocardial infarction) decreased in both the North West region and the rest of England during the first 18 months of the scheme. The reduction in mortality for incentivised conditions was greater in the North West region than in the rest of England. Compared with non-incentivised conditions within the North West region, there was a significant reduction in overall mortality for incentivised conditions, comprising a statistically significant reduction in pneumonia and non-significant reductions in the other two conditions. Comparing mortality for the incentivised conditions with mortality for these conditions in other regions, there was a significant reduction in overall mortality in the North West region, again made up of individually significant reductions in pneumonia and non-significant reductions in the other two conditions. The reduction in mortality over the 18-month period studied for non-incentivised conditions was not significantly different between the North West region and the rest of England. The between-region difference-in-differences analysis after 42 months showed that risk-adjusted mortality for the incentivised conditions fell in the rest of England and the North West region. This reduction in the rest of England was significantly larger than in the North West region and was concentrated in pneumonia. However, the reductions in mortality were larger for the non-incentivised conditions in the North West region than in the rest of England between these periods. For incentivised conditions, the triple-difference analysis shows a larger reduction in mortality for the rest of England than in the North West region between the short- and long-term periods.ConclusionsBased on the first 18 months, the AQ programme was a relatively effective and cost-effective intervention. However, findings at 42 months are open to interpretation. One interpretation is that the short-term improvements were not sustained and that the observed improvements in mortality in the non-incentivised conditions within hospitals participating in AQ were unrelated to the programme. An alternative interpretation is that these improvements are related to the positive spillover effect of AQ. Further research should be undertaken to determine the explanation for the findings.FundingThe National Institute for Health Research Health Services and Delivery Research programme.

Research on the Pre-Judging and Pre-Warning Information Management System Based on the Tourism Crisis

Determined by its compound nature such as region-difference, temporariness and wide implications, the tourism is an industry which can be dramatically influenced by crisis of different types and standards. It has become a significant point of tourism crisis management to avoid the crisis or keep the lowest loss before crisis erupts. This essay analyzes the content of the tourism crisis pre-warning information management system through its concept and features, and designs the functions of the system. Basic on the realization of its functions, this essay builds up the tourism crisis pre-warning information management system to form a closed circuit of information, and to pre-warn the crisis by reasonable information utilization on any conditions such as non-crisis, successive pre-control and failure.

An Analysis on the Differences of Regional Energy Efficiency in China - The Empirical Study Based on Theil Index

This paper divides Chinas 30 provinces into eastern region, central region and western region, uses the energy intensity as an index to analyze energy efficiency from 1995 to 2010 in China and take the empirical study in regional differences of energy efficiency by Theil index. The results of this research indicate that the total, within-region and between-region difference of energy efficiency are all constantly reducing in China. There is a rapid decrease of the total difference and within-region difference of energy efficiency. The total difference mainly consists of within-regional difference. The within-region differences of energy efficiency in the three regions are not the same. To be specific, the difference in the eastern and central regions decreases, while the difference in the western region is showing some characteristics of fluctuation.

The Research of the Lime Soil Properties on the Road in Jilin Area

Lime soil, literature [1] just gave a general rule to the mixture’s composition design. Because of the soil’s ingredient region difference, the reasonable mix of lime soil in special region must be determined by the test. This paper first quoted the formation of lime soil’s strength and the effect factor, and then regarded the non-side limitation compressive strength at different ages as inspection norm. Used orthogonal design method, the mix for the lime stabilized soil in Jilin area was investigated in this paper. The optimum mix and the main effect factor was determined by the strength at 28 days and verified by the regression strength at 90 days. In the meantime, the key problem had been summarized on the lime stabilized soil construction point and quality control.