747 research outputs found
Comparing the impact of E-learning and ICT in Higher Education institutions in Libya and United Kingdom
This paper examines the impact of E-learning and the ICT in the Higher Education (HE) in Libya and UK. A comprehensive analysis of the problems linked to the use of e-learning and ICT in Libyan institutions is performed. It is obvious the pronounced information technology (IT) gap
between Libya and the developed world due to social, political and economic conditions in an Arab country where the primary delivery educational model is essentially traditional. Then possible ways of implementing successfully e-learning and ICT in Libyan educational institutions by considering positive UK examples are explored
Cost-effective occupation dependant infrared zonal heating system for operational university buildings
Recent legislations have necessitated policies for carbon print reduction. Buildings and in particular space heating are major energy consumers and responsible for over 34% of carbon print. This work presents a method of heating only certain parts of the building using far infrared (FIR) heating. This study gives an overview on the application of infrared radiation in heating by modern methods in tune and compatibility with climate developments for the public spaces in this decade. The case study is on a university lecture theatre and the space is split up into varyingly sized zones which enable different parts of the room to be heated depending on the time and occupation of the zone. The potential to heat each zone with FIR is implemented which runs according to the machine learning algorithm (MLA) through a practical study of real CO2 data collection and validation. This allows heating to start running before the zone(s) is occupied to optimise thermal comfort. Results show that occupation zone FIR heating saves an average of 11.175kWh through various occupations compared to the currently equipped convection wall mounted radiators. Occupation forecasting of the room using random forest machine learning has an accuracy of 97.75% for 15-minutes intervals of a day. Cost analysis for the proposed occupation heating show savings of up to 76% and 14.6% compared to convection electric and gas heating respectively. FIR provides a more efficient method of heating with the capacity for zonal implementation. The results in this research demonstrate the feasibility of FIR zonal heating for non-domestic applications
Toward a Decision Support System for Mitigating Urban Heat
With the continuous rise of global urbanization, city planners and policymakers are increasingly concerned with urban heat islands (UHI), which are metropolitan areas that are significantly warmer than their surrounding rural areas. We address the United Nation’s Sustainable Development Goal 11 “Sustainable Cities and Communities,” and we design and develop a decision support system (DSS), which will help city planners and policymakers to overcome economic barriers to reach environmental sustainability goals
Similarity of chest X-ray and thermal imaging of focal pneumonia: a randomised proof of concept study at a large urban teaching hospital
OBJECTIVE: To assess the diagnostic accuracy of thermal imaging (TI) in the setting of focal consolidative pneumonia with chest X-ray (CXR) as the gold standard.
SETTING: A large, 973-bed teaching hospital in Boston, Massachusetts.
PARTICIPANTS: 47 patients enrolled, 15 in a training set, 32 in a test set. Age range 10 months to 82 years (median=50 years).
MATERIALS AND METHODS: Subjects received CXR with subsequent TI within 4 hours of each other. CXR and TI were assessed in blinded random order. Presence of focal opacity (pneumonia) on CXR, the outcome parameter, was recorded. For TI, presence of area(s) of increased heat (pneumonia) was recorded. Fisher\u27s exact test was used to assess the significance of the correlations of positive findings in the same anatomical region.
RESULTS: With TI compared with the CXR (the outcome parameter), sensitivity was 80.0% (95% CIs 29.9% to 98.9%), specificity was 57.7% (95% CI 37.2% to 76.0%). Positive predictive value of TI was 26.7% (95% CI 8.9% to 55.2%) and its negative predictive value was 93.8% (95% CI 67.7% to 99.7%).
CONCLUSIONS: This feasibility study confirms proof of concept that chest TI is consistent with CXR in suggesting similarly localised focal pneumonia with high sensitivity and negative predictive value. Further investigation of TI as a point-of-care imaging modality is warranted
A Majorana Fermion t-J Model in One Dimension
We study a rotation invariant Majorana fermion model in one dimension using
diagrammatic perturbation theory and numerical diagonalization of small
systems. The model is inspired by a Majorana representation of the
antiferromagnetic spin-1/2 chain, and it is similar in form to the t-J model of
electrons, except that the Majorana fermions carry spin-1 and Z_2 charge. We
discuss the implications of our results for the low-energy excitations of the
spin-1/2 chain. We also discuss a generalization of our model from 3 species of
Majorana fermions to N species; the SO(4) symmetric model is particularly
interesting.Comment: 29 LaTeX pages, 11 postscript figure
Accelerated DNA methylation age plays a role in the impact of cardiovascular risk factors on the human heart
BACKGROUND: DNA methylation (DNAm) age acceleration (AgeAccel) and cardiac age by 12-lead advanced electrocardiography (A-ECG) are promising biomarkers of biological and cardiac aging, respectively. We aimed to explore the relationships between DNAm age and A-ECG heart age and to understand the extent to which DNAm AgeAccel relates to cardiovascular (CV) risk factors in a British birth cohort from 1946. RESULTS: We studied four DNAm ages (AgeHannum, AgeHorvath, PhenoAge, and GrimAge) and their corresponding AgeAccel. Outcomes were the results from two publicly available ECG-based cardiac age scores: the Bayesian A-ECG-based heart age score of Lindow et al. 2022 and the deep neural network (DNN) ECG-based heart age score of Ribeiro et al. 2020. DNAm AgeAccel was also studied relative to results from two logistic regression-based A-ECG disease scores, one for left ventricular (LV) systolic dysfunction (LVSD), and one for LV electrical remodeling (LVER). Generalized linear models were used to explore the extent to which any associations between biological cardiometabolic risk factors (body mass index, hypertension, diabetes, high cholesterol, previous cardiovascular disease [CVD], and any CV risk factor) and the ECG-based outcomes are mediated by DNAm AgeAccel. We derived the total effects, average causal mediation effects (ACMEs), average direct effects (ADEs), and the proportion mediated [PM] with their 95% confidence intervals [CIs]. 498 participants (all 60-64 years) were included, with the youngest ECG heart age being 27 and the oldest 90. When exploring the associations between cardiometabolic risk factors and Bayesian A-ECG cardiac age, AgeAccelPheno appears to be a partial mediator, as ACME was 0.23 years [0.01, 0.52] p = 0.028 (i.e., PM≈18%) for diabetes, 0.34 [0.03, 0.74] p = 0.024 (i.e., PM≈15%) for high cholesterol, and 0.34 [0.03, 0.74] p = 0.024 (PM≈15%) for any CV risk factor. Similarly, AgeAccelGrim mediates ≈30% of the relationship between diabetes or high cholesterol and the DNN ECG-based heart age. When exploring the link between cardiometabolic risk factors and the A-ECG-based LVSD and LVER scores, it appears that AgeAccelPheno or AgeAccelGrim mediate 10-40% of these associations. CONCLUSION: By the age of 60, participants with accelerated DNA methylation appear to have older, weaker, and more electrically impaired hearts. We show that the harmful effects of CV risk factors on cardiac age and health, appear to be partially mediated by DNAm AgeAccelPheno and AgeAccelGrim. This highlights the need to further investigate the potential cardioprotective effects of selective DNA methyltransferases modulators
Experimental observation of topological Fermi arcs in type-II Weyl semimetal MoTe2
Weyl semimetal is a new quantum state of matter [1-12] hosting the condensed
matter physics counterpart of relativisticWeyl fermion [13] originally
introduced in high energy physics. The Weyl semimetal realized in the TaAs
class features multiple Fermi arcs arising from topological surface states [10,
11, 14-16] and exhibits novel quantum phenomena, e.g., chiral anomaly induced
negative mag-netoresistance [17-19] and possibly emergent supersymmetry [20].
Recently it was proposed theoretically that a new type (type-II) of Weyl
fermion [21], which does not have counterpart in high energy physics due to the
breaking of Lorentz invariance, can emerge as topologically-protected touching
between electron and hole pockets. Here, we report direct spectroscopic
evidence of topological Fermi arcs in the predicted type-II Weyl semimetal
MoTe2 [22-24]. The topological surface states are confirmed by directly
observing the surface states using bulk-and surface-sensitive angle-resolved
photoemission spectroscopy (ARPES), and the quasi-particle interference (QPI)
pattern between the two putative Fermi arcs in scanning tunneling microscopy
(STM). Our work establishes MoTe2 as the first experimental realization of
type-II Weyl semimetal, and opens up new opportunities for probing novel
phenomena such as exotic magneto-transport [21] in type-II Weyl semimetals.Comment: submitted on 01/29/2016. Nature Physics, in press. Spectroscopic
evidence of the Fermi arcs from two complementary surface sensitive probes -
ARPES and STS. A comparison of the calculated band structure for T_d and 1T'
phase to identify the topological Fermi arcs in the T_d phase is also
included in the supplementary informatio
Sanitation in informal settlements in East Africa (3ksan)
Improving access to sanitation in slums in East Africa is a challenge. The 3ksan project has been working to identify the barriers and catalysts to sanitation in Kigali, Kampala and Kisumu. Household surveys in the informal settlements in these three cities have provided insight into the different levels of service provision and demand, access to financial services, and perceptions of enforcement of the regulations. This paper presents key results from the household survey, highlighting the different challenges in the three cities
Scrotal calcinosis due to resorption of cyst walls: a case report
<p>Abstract</p> <p>Introduction</p> <p>Scrotal calcinosis is a rare benign entity defined as the presence of multiple calcified nodules within the scrotal skin. There are controversies about the origin of this entity. In fact, it is still debatable whether scrotal calcinosis is an idiopathic growth or dystrophic calcification of dartoic muscles. It is also unclear whether scrotal calcinosis originates from inflammation of epidermal cysts affected by mild to moderate inflammation of mononuclear cells, from foreign body granuloma formation followed by resorption of cyst walls or from eccrine epithelial cysts.</p> <p>Case presentation</p> <p>We report a 41-year-old male Turkish patient presenting with a 10-year history of scrotal tumours increasing slowly in size and number. Histopathologically, there was no epithelial lining around the calcified nodules, but there was fibrosis adjacent to atrophic stratified squamous epithelium.</p> <p>Conclusion</p> <p>Results of histopathological examinations suggested that scrotal calcinosis might have been due to resorption of cyst walls. Surgery remains the key for this problem. In cases of non-massive scrotal calcinosis, like the case presented here, excision of the nodules from the affected part of the scrotal wall and repairing the defect with horizontal stitches offer good cosmetic results without relapse.</p
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