216 research outputs found
Non-universal Voronoi cell shapes in amorphous ellipsoid packings
In particulate systems with short-range interactions, such as granular matter
or simple fluids, local structure plays a pivotal role in determining the
macroscopic physical properties. Here, we analyse local structure metrics
derived from the Voronoi diagram of configurations of oblate ellipsoids, for
various aspect ratios and global volume fractions . We focus
on jammed static configurations of frictional ellipsoids, obtained by
tomographic imaging and by discrete element method simulations. In particular,
we consider the local packing fraction , defined as the particle's
volume divided by its Voronoi cell volume. We find that the probability
for a Voronoi cell to have a given local packing fraction shows the
same scaling behaviour as function of as observed for random sphere
packs. Surprisingly, this scaling behaviour is further found to be independent
of the particle aspect ratio. By contrast, the typical Voronoi cell shape,
quantified by the Minkowski tensor anisotropy index ,
points towards a significant difference between random packings of spheres and
those of oblate ellipsoids. While the average cell shape of all cells
with a given value of is very similar in dense and loose jammed sphere
packings, the structure of dense and loose ellipsoid packings differs
substantially such that this does not hold true. This non-universality has
implications for our understanding of jamming of aspherical particles.Comment: 6 pages, 5 figure
Tomographic analysis of jammed ellipsoid packings
Disordered packings of ellipsoidal particles are an important model for disordered granular matter. Here we report a way to determine the average contact number of ellipsoid packings from tomographic analysis. Tomographic images of jammed ellipsoid packings prepared by vertical shaking of loose configurations are recorded and the positions and orientations of the ellipsoids are reconstructed. The average contact number can be extracted from a contact number scaling (CNS) function. The size of the particles, that may vary due to production inaccuracies, can also be determined by this method
Preparation of Innovative PEG/Tannic Acid/TiO2 Hydrogels and Effect of Tannic Acid Concentration on Their Hydrophilicity
Hydrogels are materials that can be used in biomedical and medical applications and have gained increasing interest in recent years. In order to obtain a wide variety of properties, hydrogels containing more innovative components still need to be produced and investigated. In this study, for this purpose, an innovative injectable polyethylene glycol (PEG)/tannic acid (TA)/TiO2 hydrogels were prepared and their properties were investigated. TA, used as a crosslinker for PEG, was used in different concentrations (400 mg, 800 mg, and 1.2 g) in hydrogel preparation to analyse the effect of tannic acid on the properties of the obtained hydrogels. PEG/0.4TA/TiO2, PEG/0.8TA/TiO2 and PEG/1.2TA/TiO2 hydrogels prepared by using FeCl3 to increase the crosslink density in its content and by adding TiO2 due to its antimicrobial properties, were characterized by UV-VIS spectroscopy, FTIR and contact angle measurements. . With the UV-VIS and FTIR spectra, it is seen that TA/Fe3+ metal complexes are formed and the three-dimensional hydrogel network is successfully completed with the help of these metal complexes formed by the addition of FeCl3. In addition, the contact angle measurements of the PEG/0.4TA/TiO2, PEG/0.8TA/TiO2 and PEG/1.2TA/TiO2 hydrogels were found to be 18°, 27° and 27° degrees, respectively, and the hydrophilicity of the hydrogels was reached at constant value in the samples added 0.8 g TA. The obtained new injectable PEG/TA/TiO2 hydrogel is promising for use in biomedical and medical fields, thanks to its contact angle values ​​of less than 90° for biocompatibility and its biocompatible components
Heavy Metals Distribution and Pollution in the Sediments of the Wadi Gaza Mouth, Eastern Mediterranean Coast, Palestine
Wadi Gaza is the most important wetland in Gaza Strip. Due to the difficult economic conditions, the Israeli occupation and lack of the resources, Wadi Gaza became a place for solid and liquid waste disposal from surrounding provinces. The aim of this study is to assess the heavy metals in the sediments of the Wadi Gaza, North, and South of downstream along the beach of Gaza Strip. This was achieved through sediment sampling along the course of the Wadi downstream; north and south of the beach sands, and the geochemical analysis was done in the Ministry of Health Laboratories. The concentrations of Mn, Zn, Ni, Cd, Cu, and Pb were determined in the sediments, using atomic absorption spectrophotometer
Review of Green Food Processing techniques. Preservation, transformation, and extraction
This review presents innovative food processing techniques and their role in promoting sustainable food industry. These techniques (such as microwave, ultrasound, pulse electric field, instant controlled pressure drop, supercritical fluid processing) in the frontiers of food processing, food chemistry, and food microbiology, are not new and were already used for> 30 years by academia and industry. We will pay special attention to the strategies and the tools available to make preservation, transformation and extraction greener and present them as success stories for research, education and at industrial scale. The design of green and sustainable processes is currently a hot research topic in food industry. Herein we aimed to describe a multifaceted strategy (innovative technologies, process intensification, bio-refinery concept) to apply this concept at research, educational, and industrial level.Industrial relevance: Green Food Processing could be a new concept to meet the challenges of the 21st century, to protect both the environment and consumers, and in the meantime enhance competition of industries to be more ecologic, economic and innovative. This green approach should be the result of a whole chain of values in both senses of the term: economic and responsible, starting from the production and harvesting of food raw materials, processes of preservation, transformation, and extraction together with formulation and marketing
Low back pain education and short term quality of life: a randomized trial
BACKGROUND: Different interventions can reduce the burden of the chronic low back pain. One example is the use of a 'Back School Programme'. This is a brief therapy that uses a health education method to empower participants through a procedure of assessment, education and skill development. This study aimed to evaluate to what extent the programme could improve quality of life in those who suffer from the condition. METHODS: This was a randomized controlled trial. One-hundred and two female patients with low back pain (n = 102) were randomly allocated into two groups, matched in terms of age, weight, education, socioeconomic status, occupation and some aspects of risk behavior. Group 1 (back school group, n = 50) but not group 2 (clinic group, n = 52) received the 'Back School Programme'. Then quality of life using the Short Form Health Survey (SF-36) was assessed at two time points: at baseline and at three months follow-up. The findings were compared both within and between two groups. RESULTS: The 'Back School Programme' was effective in improving patients' quality of life; significant differences were found on all eight subscales of the SF-36 for group 1. In the clinic group (group 2), improvement was observed on three scales (bodily pain, vitality and mental health) but these improvements were less than in group 1. The mean improvement over all eight subscales of the SF-36 was significantly better for the 'Back School Programme' group. CONCLUSION: The 'Back School Programme' is an effective intervention and might improve the quality of life over a period of 3 months in patients who experience chronic low back pain
Search for dark matter produced in association with bottom or top quarks in √s = 13 TeV pp collisions with the ATLAS detector
A search for weakly interacting massive particle dark matter produced in association with bottom or top quarks is presented. Final states containing third-generation quarks and miss- ing transverse momentum are considered. The analysis uses 36.1 fb−1 of proton–proton collision data recorded by the ATLAS experiment at √s = 13 TeV in 2015 and 2016. No significant excess of events above the estimated backgrounds is observed. The results are in- terpreted in the framework of simplified models of spin-0 dark-matter mediators. For colour- neutral spin-0 mediators produced in association with top quarks and decaying into a pair of dark-matter particles, mediator masses below 50 GeV are excluded assuming a dark-matter candidate mass of 1 GeV and unitary couplings. For scalar and pseudoscalar mediators produced in association with bottom quarks, the search sets limits on the production cross- section of 300 times the predicted rate for mediators with masses between 10 and 50 GeV and assuming a dark-matter mass of 1 GeV and unitary coupling. Constraints on colour- charged scalar simplified models are also presented. Assuming a dark-matter particle mass of 35 GeV, mediator particles with mass below 1.1 TeV are excluded for couplings yielding a dark-matter relic density consistent with measurements
Large-scale geo-facial image analysis
While face analysis from images is a well-studied area, little work has explored the dependence of facial appearance on the geographic location from which the image was captured. To fill this gap, we constructed GeoFaces, a large dataset of geotagged face images, and used it to examine the geo-dependence of facial features and attributes, such as ethnicity, gender, or the presence of facial hair. Our analysis illuminates the relationship between raw facial appearance, facial attributes, and geographic location, both globally and in selected major urban areas. Some of our experiments, and the resulting visualizations, confirm prior expectations, such as the predominance of ethnically Asian faces in Asia, while others highlight novel information that can be obtained with this type of analysis, such as the major city with the highest percentage of people with a mustache
Telecardiology Application in Jordan: Its Impact on Diagnosis and Disease Management, Patients’ Quality of Life, and Time- and Cost-Savings
Objectives. To assess the impact of live interactive telecardiology on diagnosis and disease management, patients’ quality of life, and time- and cost-savings. Methods. All consecutive patients who attended or were referred to the teleclinics for suspected cardiac problems in two hospitals in remote areas of Jordan during the study period were included in the study. Patients were interviewed for relevant information and their quality of life was assessed during the first visit and 8 weeks after the last visit. Results. A total of 76 patients were included in this study. Final diagnosis and treatment plan were established as part of the telecardiology consultations in 71.1% and 77.3% of patients, respectively. Patients’ travel was avoided for 38 (50.0%) who were managed locally. The majority of patients perceived that the visit to the telecardiology clinic results in less travel time (96.1%), less waiting time (98.1%), and lower cost (100.0%). Telecardiology consultations resulted in an improvement in the quality of life after two months of the first visit. Conclusions. Telecardiology care in remote areas of Jordan would improve the access to health care, help to reach proper diagnosis and establish the treatment plan, and improve the quality of life
Effect of extracranial lesion severity on outcome of endovascular thrombectomy in patients with anterior circulation tandem occlusion: analysis of the TITAN registry
Introduction Endovascular treatment (EVT) for tandem occlusion (TO) of the anterior circulation is complex but effective. The effect of extracranial internal carotid artery (EICA) lesion severity on the outcomes of EVT is unknown. In this study we investigated the effect of EICA lesion severity on the outcomes of tandem occlusion EVT. Methods A multicenter retrospective TITAN (Thrombectomy In TANdem lesions) study that included 18 international endovascular capable centers was performed. Patients who received EVT for atherosclerotic TO with or without EICA lesion intervention were included. Patients were divided into two groups based on the EICA lesion severity (high-grade stenosis (>= 90% North American Symptomatic Carotid Endarterectomy Trial) vs complete occlusion). Outcome measures included the 90-day clinical outcome (modified Rankin Scale score (mRS)), angiographic reperfusion (modified Thrombolysis In Cerebral Ischemia (mTICI) at the end of the procedure), procedural complications, and intracranial hemorrhage at 24 hours follow-up. Results A total of 305 patients were included in the study, of whom 135 had complete EICA occlusion and 170 had severe EICA stenosis. The EICA occlusion group had shorter mean onset-to-groin time (259 +/- 120 min vs 305 +/- 202 min;p=0.037), more patients with diabetes, and fewer with hyperlipidemia. With respect to the outcome, mTICI 2b-3 reperfusion was lower in the EICA occlusion group (70% vs 81%;p=0.03). The favorable outcome (90-day mRS 0-2), intracerebral hemorrhage and procedural complications were similar in both groups. Conclusion Atherosclerotic occlusion of the EICA in acute tandem strokes was associated with a lower rate of mTICI 2b-3 reperfusion but similar functional and safety outcomes when compared with high-grade EICA stenosis
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