Is there an association between leukoaraiosis volume and diabetes?

Objectives: The relation between white matter loss (WML) and diabetes is still debated. The aim of this study was to investigate the correlation between typical WML— and diabetesrelated magnetic resonance imaging (MRI) findings in a cohort of patients scheduled for carotid endarterectomy (CEA). Materials and methods: Ninety-three consecutive patients (mean age 71 ± 9 years; male 71) were included in a single-centre retrospective study. All the patients underwent MRI as baseline evaluation prior to CEA. A neuroradiologist blinded to the presence of risk factors calculated WML volume and number of lesions on FLAIR images using a semi-automated segmentation technique. Receiver operating characteristics analysis was performed to search for any association between WML volume and the number of WML lesions. The Mann—Whitney tests were used to determine significant WML differences between diabetic and non-diabetic patients. Logistic regression analysis was performed to evaluate the potential association of other variables. Results: The prevalence of diabetes was 20.4% (n = 19). WML volume and number of WML lesions were significantly associated with diabetes (P = 0.001). A statistically significant difference in WML volume was found between diabetic and non-diabetic patients (P < 0.0001). Only diabetes, among all the investigated variables (WML volume, CAD status, age, smoking status, gender, hypertension, hyperlipidemia, diabetes) was significantly associated with WML (P = 0.0001)

Relationship between epicardial fat volume on cardiac CT and atherosclerosis severity in three-vessel coronary artery disease: a single-center cross-sectional study

BACKGROUND: The ideal treatment strategy for stable three-vessel coronary artery disease (CAD) patients are difficult to determine and for patients undergoing conservative treatment, imaging evidence of coronary atherosclerotic severity progression remains limited. Epicardial fat volume (EFV) on coronary CT angiography (CCTA) has been considered to be associated with coronary atherosclerosis. Therefore, this study aims to evaluate the relationship between EFV level and coronary atherosclerosis severity in three-vessel CAD. METHODS: This retrospective study enrolled 252 consecutive patients with three-vessel CAD and 252 normal control group participants who underwent CCTA between January 2018 and December 2019. A semi-automatic method was developed for EFV quantification on CCTA images, standardized by body surface area. Coronary atherosclerosis severity was evaluated and scored by the number of coronary arteries with ≥ 50% stenosis on coronary angiography. Patients were subdivided into groups on the basis of lesion severity: mild (score = 3 vessels, n = 85), moderate (3.5 vessels ≤ score < 4 vessels, n = 82), and severe (4 vessels ≤ score ≤ 7 vessels, n = 85). The independent sample t-test, analysis of variance, and logistic regression analysis were used to evaluate the associations between EFV level and severity of coronary atherosclerosis. RESULTS: Compared with normal controls, three-vessel CAD patients had significantly higher EFV level (65 ± 22 mL/m(2) vs. 48 ± 19 mL/m(2); P < 0.001). In patients with three-vessel CAD, there was a progressive decline in EFV level as the score of coronary atherosclerosis severity increased, especially in those patients with a body mass index (BMI) ≥ 25 kg/m(2) (75 ± 21 mL/m(2) vs. 72 ± 22 mL/m(2) vs. 62 ± 17 mL/m(2); P < 0.05). Multivariable regression analysis showed that both BMI (OR 3.40, 95% CI 2.00–5.78, P < 0.001) and the score of coronary atherosclerosis severity (OR 0.49, 95% CI 0.26–0.93, P < 0.05) were independently related to the change of EFV level. CONCLUSION: Three-vessel CAD patients do have higher EFV level than the normal controls. While, there may be an inverse relationship between EFV level and the severity of coronary atherosclerosis in patients with three-vessel CAD

Urbanization and dengue ecology

As mudanças demográficas ocorridas nos países subdesenvolvidos, a partir dos anos 60, geradas por intenso fluxo migratório rural-urbano, resultaram em crescimento desordenado das cidades, nas quais se destacam a carência de facilidades - em particular, de habitação e saneamento básico. Cerca de 20% da população das grandes e médias cidades estão vivendo em favelas, cortiços ou em áreas de invasão. Pela falta de abastecimento de água, há necessidade de armazená-la precariamente, tal como pela ausência de destino adequado do lixo ocorre a proliferação de criadouros potenciais do Aedes aegypti, principal mosquito vetor da dengue, ou seja, depósitos improvisados para água potável e recipientes em que a água é acumulada, constituídos principalmente por latas, plásticos e garrafas usadas. A indústria moderna, por outro lado, privilegia a produção de material descartável. O vírus do dengue tem sua propagação facilitada pela intensidade e freqüência dos meios de transporte, os quais favorecem também a disseminação dos vetores da doença. Estes são alguns dos fatores que tentam explicar o ressurgimento do dengue, a mais importante arbovirose no mundo atualmente e que acomete milhares de pessoas todos os anos.Demographic changes occurring in underdeveloped countries due to intense rural-urban migration since the 1960s have resulted in overcrowded cities with multiple deficiencies, particularly in housing and basic sanitation. Some 20% of the population in large and medium-sized cities live in slums or under similar conditions. Lack of regular water supply and public garbage collection foster the proliferation of potential breeding sites for Aedes aegypti (the main mosquito vector for dengue), including precarious reservoirs for potable water and disposable recipients which accumulate water, like used cans and plastic and glass bottles. Modern industries also produce large volumes of disposable materials. Propagation of the dengue virus and the spread of dengue vectors are favored by the high intensity, frequency, and speed of private and public transportation. Such factors can help explain the re-emergence of dengue, the most important arbovirus in the world today, affecting thousands of people each year

Lean Burn Gas Engine with a Pre Chamber Ignition System: Grid Independence Study and Design Optimization

Pre-chamber ignition systems are used in the lean burn gas engines to avail benefits of low emissions and high efficiency. Numerical investigations of these pre-chamber ignition systems are challenging due to the requirement of local refinement inside the pre-chamber, especially between the electrodes. In addition, high pressurized jets from the pre-chamber small holes require jet-directed fine mesh, which is quite challenging with the cylinder hexahedron coarse moving mesh. In the present work, a specialized mesh with the optimized spatial grid size distribution of the single cylinder engine with pre-chamber ignition system is generated and the influence of the pre-chamber geometry on charge motion and exhaust gas residuals inside pre-chamber is numerically investigated. Firstly, grid independence study of a single cylinder engine and pre-chamber ignition system is conducted respectively and validated with experimental data of the open cycle at motored operation for reference geometry. Afterward, a study of pre-chamber ignition system geometry is conducted using an open-cycle mesh (valves and piston motion are included), to optimize the charge motion and exhaust gas residuals inside the pre-chamber. Subsequently, charge motion inside the pre-chamber from open cycle simulation before ignition is mapped with closed-cycle mesh (no valves included) using Star-CD SMAP feature, to initialize the similar flow conditions inside the pre-chamber ignition system, which in turn is used to study the flame kernel development. The mapping process drastically reduces overall grid size and consequently time and computational power required by simulation without affecting the accuracy of results. Several pre-chamber designs were evaluated and the influence of pre-chamber geometry on flow velocity, TKE and exhaust gas residuals inside the spark gap and their subsequent effects on the flame (kernel) development were studied

single grain grinding an experimental and fem assessment

Abstract Peripheral grinding is inherently complex due to peculiar factors such as: the non deterministic microgeometry of the grinding wheel, the composition of the grinding wheel, essentially non homogeneous, the cutting process dynamics, where the grains' cutting edges operate on a surface whose microgeometry is the result of the cutting actions of the preceding abrasive grains. This paper compares the results of the experimental analysis of the effect of single cutting grains on the actual microgeometry of worked surfaces, and the results obtained by a FEM cutting model where the measured microgeometry of the cutting grains is considered

Current Available Computer-Aided Detection Catches Cancer but Requires a Human Operator

Introduction: This study intends to show that the current widely used computer-aided detection (CAD) may be helpful, but it is not an adequate replacement for the human input required to interpret mammograms accurately. However, this is not to discredit CAD’s ability but to further encourage the adoption of artificial intelligence-based algorithms into the toolset of radiologists. Methods: This study will use Hologic (Marlborough, MA, USA) and General Electric (Boston, MA, USA) CAD read images provided by patients found to be Breast Imaging Reporting and Data System (BI-RADS) 6 from 2019 to 2020. In addition, patient information will be pulled from our institution’s emergency medical record to confirm the findings seen in the pathologist report and the radiology read. Results: Data from a total of 24 female breast cancer patients from January 31st 2019 to April 31st 2020, was gathered from our institution’s emergency medical record with restrictions in patient numbers due to coronavirus disease 2019 (COVID-19). Within our patient population, CAD imaging was shown to be statistically significant in misidentifying breast cancer, while radiologist interpretation still proves to be the most effective tool. Conclusion: Despite a low sample size due to COVID-19, this study found that CAD did have significant difficulty in differentiating benign vs. malignant lesions. CAD should not be ignored, but it is not specific enough. Although CAD often marks cancer, it also marks several areas that are not cancer. CAD is currently best used as an additional tool for the radiologist

An experimental right atrium platform to assess recirculation in hemodialysis catheters

Hemodialysis (HD) is a treatment supporting decreased kidney function, via a catheter inserted into the heart’s Right Atrium (RA). Recirculation is a source of inefficiency for treatment, where blood is dialysed again due to poor catheter design. Lab-testing is still relatively unexplored, hence, a mechanical testing system was designed with the intention of providing a consistent and repeatable environment for testing HD catheters. System geometry was composed using a Computer-Aided Design (CAD) model of a heart, with the RA scaled to appropriate dimensions, and a PolyDiMethylSiloxane (PDMS) model produced through 3D printing and negative wax casting. Pulsatile blood flow was mimicked by peristaltic pumps driving a blood analogue (BA). Recirculation was induced by adding dyed BA to the system via the catheter and measured using a colourimeter. The developed platform was initially evaluated using two catheters, demonstrating capability to accurately replicate atrial hemodynamic conditions. Two step-tipped catheters, A and B, were tested at 350 ml/min, producing recirculation values of 13.11% and 18.58%, respectively. The results exhibit the ability of the system developed to evaluate HD catheter performance, with potential to explore a wider range of tip geometries relevant to clinical preference. Furthermore, this advancement towards an anatomically accurate lab-based test system could be paired with computational methods to progress the evaluation of such medical devices and enhance their development