Joint Coding for Proactive Caching with Changing File Popularities

Proactive caching is a promising technique used to minimize peak traffic rates by storing popular data, in advance, at different nodes in the network. We study a cellular network with one base station (BS) communicating with multiple mobile units (MUs). The BS has a number of cached files to be delivered to the MUs upon demand, and the popularities of these files are changing over time. We show that proactively and constantly updating the MU finite caches and jointly encoding the delivery of different demanded files to the MUs over different time slots minimize the delivery sum rate. We propose two different schemes for a two different scenarios, where the file popularities over time can be either arbitrary increasing or decreasing for the first scheme and decreases with demand for the second scheme. Numerical results show the benefits of the proposed schemes, over conventional caching schemes, in terms of reducing the delivery sum rate. 2017 IEEE.This work is supported by NSERC discovery grant. The research work of Tamer Khattab was made possible by grant number NPRP 7-923-2-344 from Qatar National Research Fund, QNRF (a member of the Qatar Foundation, QF). The statements made herein are the sole responsibilityScopu

Progressive Collapse Analysis of the Champlain Towers South in Surfside, Florida

Since the Ronan Point collapse in the UK in 1968, the progressive collapse analysis of residential buildings has gradually drawn the attention of civil engineers and the scientific community. Recent advances in computer science and the development of new numerical methodologies allow us to perform high-fidelity collapse simulations. This paper assesses different scenarios that could have hypothetically caused the collapse of the Champlain Tower South Condo in Surfside, Florida, in 2021, one of the most catastrophic progressive collapse events that has ever occurred. The collapse analysis was performed using the latest developments in the Applied Element Method (AEM). A high-fidelity numerical model of the building was developed according to the actual structural drawings. Several different collapse hypotheses were examined, considering both column failures and degradation scenarios. The analyses showed that the failure of deep beams at the pool deck level, directly connected to the perimeter columns of the building, could have led to the columns’ failure and subsequent collapse of the eastern wing of the building. The simulated scenario highlights the different stages of the collapse sequence and appears to be consistent with what can be observed in the footage of the actual collapse. To improve the performance of the structure against progressive collapse, two modifications to the original design of the building were introduced. From the analyses, it was found that disconnecting the pool deck beam from the perimeter columns could have been effective in preventing the local collapse of the pool deck slab from propagating to the rest of the building. Moreover, these analyses indicate that enhancing the torsional strength and stiffness of the core could have prevented the collapse of the eastern part of the building, given the assumptions and initiation scenarios considered

A methodology to quantify debris generation after a seismic event

Seismic damage simulation at the regional scale can potentially provide valuable information that can facilitate decision making, enhance planning for disaster mitigation, and reduce human and economic losses. When an earthquake happens, building damage assessment is one of the important issues in earthquake loss estimation. The amount of debris generated and the effects on related critical infrastructures is also an essential information to evaluate. Indeed, as cascading consequence of debris accumulation, the road network can be interrupted. This entails an overall increase in the average number of people who have difficulty evacuating, with high risk that residents cannot evacuate any areas. This study proposes a method to evaluate the debris affected area and the debris amount as a function of the geometric characteristics and the level of damage of the buildings. The first part of this work is focused on the evaluation of the debris area’s extension by numerical simulations. Comparison of the results with images of real seismic damaged structures allows the validation of the results. Besides, experimental tests on a small shaking table are performed to validate the numerical simulations. A mathematic model based on the results is also proposed

The Burden of Revision Sinonasal Surgery in the UK – Data from the Chronic Rhinosinusitis Epidemiology Study (CRES); a cross sectional study

Objectives/Hypothesis The aim of this study was to investigate the surgical revision rate in patients with Chronic Rhinosinusitis (CRS) in the UK CRS Epidemiology Study (CRES). Previous evidence from national Sinonasal Audit showed that 1459 CRS patients demonstrated a surgical revision rate 19.1% at 5 years, with highest rates seen in those with polyps (20.6%). Setting Thirty secondary care centres around the UK. Participants A total of 221 controls and 1249 patients with CRS were recruited to the study including those with polyps (CRSwNPs), without polyps (CRSsNPs) and with allergic fungal rhinosinusitis (AFRS). Interventions Self-administered questionnaire. Primary outcome measure The need for previous sinonasal surgery. Results A total of 651 patients with CRSwNPs, 553 with CRSsNPs and 45 with AFRS were included. A total of 396 (57%) of patients with CRSwNPs/AFRS reported having undergone previous endoscopic nasal polypectomy (ENP), of which 182 of the 396 (46%) reported having received more than one operation. The mean number of previous surgeries per patient in the revision group was 3.3 (range 2 to 30) and a mean duration of time of 10 years since the last procedure. The average length of time since their first operation up to inclusion in the study was 15.5 years (range 0-74). Only 27.9% of all patients reporting a prior ENP had received concurrent endoscopic sinus surgery (ESS) (n=102). For comparison, surgical rates in patients with CRSsNPs were significantly lower; 13% of cases specifically reported ESS and of those only 30% reported multiple procedures (chi-squared p < 0.001). Conclusions This study demonstrated there is a high burden of both primary and revision surgery in patients with CRS, worst in those with AFRS and least in those with CRSsNPs. The burden of revision surgery appears unchanged in the decade since the Sinonasal Audit

Prediabetes management in the Middle East, Africa and Russia: Current status and call for action:

Most data on the burden of diabetes and prediabetes are from countries where local infrastructure can support reliable estimates of the burden of non-communicable diseases. Countries in the Middle ..

A comparative randomized clinical trial evaluating the efficacy and safety of tacrolimus versus hydrocortisone as a topical treatment of atopic dermatitis in children

Background: Atopic dermatitis (AD) aetiology is not exactly identified, but it is characterized by pruritic skin reactions with elevation in the levels of inflammatory markers. Despite the fact that Corticosteroids are the mainstay therapy in the management of AD, they have many local and systemic adverse effects.Objective: The aim of this study is to evaluate the efficacy and safety of topical tacrolimus ointment in comparison to topical hydrocortisone cream in the management of the AD of children diagnosed with AD.Patients and Methods: This study was conducted on 200 children with AD. They were simply randomized into two groups, the tacrolimus group treated with 0.03% topical tacrolimus ointment and the hydrocortisone group treated with 1% hydrocortisone cream twice daily during the 3 weeks study period.Results: At the end of the study, both the tacrolimus and hydrocortisone groups showed a significant decline in the mean serum level of IL-10, IL-17, and IL-23 (p &lt; 0.05) when compared to their baseline levels. However, the tacrolimus group showed a more significant decrease (p &lt; 0.05) in the mean serum level of IL-10, IL-17, and IL-23 as compared to the hydrocortisone group [Mean differences = 1.600, 95% CI: 0.9858–2.214; 1.300, 95% CI: 1.086–1.514 and 4.200, 95% CI: 3.321–5.079]. Moreover, the median mEASI decreased similarly from 32 to 21 in the tacrolimus group and from 30 to 22 in the hydrocortisone group (p &gt; 0.05) [Median difference = −2.000, 95% CI: −2.651 to −1.349; Median difference = 1.000, 95% CI: 0.3489–1.651]. Mild to moderate transient stinging and erythema were the main adverse effects that showed higher incidence in the tacrolimus group than in the hydrocortisone group (p &lt; 0.05). In most cases, they resolved within 3–4 days. Besides, tacrolimus ointment did not cause skin atrophy as compared to the hydrocortisone group (p &lt; 0.05).Conclusion: Tacrolimus ointment is more beneficial than hydrocortisone cream in managing AD in children in terms of lowering the inflammatory markers, however, there is no difference on the dermatitis severity scale. Moreover, tacrolimus is safer with a better side effect profile compared to hydrocortisone.Trial Registration: The trial is registered at ClinicalTrials.gov (CT.gov identifier: NCT05324618

Molecular markers of anti-malarial drug resistance in Lahj Governorate, Yemen: baseline data and implications

<p>Abstract</p> <p>Background</p> <p>This is an investigation of anti-malarial molecular markers coupled with a therapeutic efficacy test of chloroquine (CQ) against falciparum malaria in an area of unstable malaria in Lahj Governorate, Yemen. The study was aimed at assessment of therapeutic response to CQ and elucidation of baseline information on molecular markers for <it>Plasmodium falciparum </it>resistance against CQ and sulphadoxine/pyrimethamine (SP).</p> <p>Methods</p> <p>Between 2002 and 2003 the field test was conducted according to the standard WHO protocol to evaluate the therapeutic efficacy of CQ in 124 patients with falciparum malaria in an endemic area in Lahj Governorate in Yemen. Blood samples collected during this study were analysed for <it>P. falciparum </it>chloroquine resistance transporter gene (<it>pfcrt</it>)-76 polymorphisms, mutation <it>pfcrt-</it>S163R and the antifolate resistance-associated mutations dihydrofolate reductase (<it>dhfr</it>)-C59R and dihydropteroate synthase (<it>dhps</it>)-K540E. Direct DNA sequencing of the <it>pfcrt </it>gene from three representative field samples was carried out after DNA amplification of the 13 exons of the <it>pfcrt </it>gene.</p> <p>Results</p> <p>Treatment failure was detected in 61% of the 122 cases that completed the 14-day follow-up. The prevalence of mutant <it>pfcrt </it>T76 was 98% in 112 amplified pre-treatment samples. The presence of <it>pfcrt </it>T76 was poorly predictive of <it>in vivo </it>CQ resistance (PPV = 61.8%, 95% CI = 52.7-70.9). The prevalence of <it>dhfr </it>Arg-59 mutation in 99 amplified samples was 5%, while the <it>dhps </it>Glu-540 was not detected in any of 119 amplified samples. Sequencing the <it>pfcrt </it>gene confirmed that Yemeni CQ resistant <it>P. falciparum </it>carry the old world (Asian and African) CQ resistant haplotype CVIETSESI at positions 72,73,74,75,76,220,271, 326 and 371.</p> <p>Conclusion</p> <p>This is the first study to report baseline information on the characteristics and implications of anti-malarial drug resistance markers in Yemen. It is also the first report of the haplotype associated with CQR <it>P. falciparum </it>parasites from Yemen. Mutant <it>pfcrt</it>T76 is highly prevalent but it is a poor predictor of treatment failure in the study population. The prevalence of mutation <it>dhfr</it>Arg59 is suggestive of emerging resistance to SP, which is currently a component of the recommended combination treatment of falciparum malaria in Yemen. More studies on these markers are recommended for surveillance of resistance in the study area.</p

Antimicrobial resistance among migrants in Europe: a systematic review and meta-analysis

BACKGROUND: Rates of antimicrobial resistance (AMR) are rising globally and there is concern that increased migration is contributing to the burden of antibiotic resistance in Europe. However, the effect of migration on the burden of AMR in Europe has not yet been comprehensively examined. Therefore, we did a systematic review and meta-analysis to identify and synthesise data for AMR carriage or infection in migrants to Europe to examine differences in patterns of AMR across migrant groups and in different settings. METHODS: For this systematic review and meta-analysis, we searched MEDLINE, Embase, PubMed, and Scopus with no language restrictions from Jan 1, 2000, to Jan 18, 2017, for primary data from observational studies reporting antibacterial resistance in common bacterial pathogens among migrants to 21 European Union-15 and European Economic Area countries. To be eligible for inclusion, studies had to report data on carriage or infection with laboratory-confirmed antibiotic-resistant organisms in migrant populations. We extracted data from eligible studies and assessed quality using piloted, standardised forms. We did not examine drug resistance in tuberculosis and excluded articles solely reporting on this parameter. We also excluded articles in which migrant status was determined by ethnicity, country of birth of participants' parents, or was not defined, and articles in which data were not disaggregated by migrant status. Outcomes were carriage of or infection with antibiotic-resistant organisms. We used random-effects models to calculate the pooled prevalence of each outcome. The study protocol is registered with PROSPERO, number CRD42016043681. FINDINGS: We identified 2274 articles, of which 23 observational studies reporting on antibiotic resistance in 2319 migrants were included. The pooled prevalence of any AMR carriage or AMR infection in migrants was 25·4% (95% CI 19·1-31·8; I2 =98%), including meticillin-resistant Staphylococcus aureus (7·8%, 4·8-10·7; I2 =92%) and antibiotic-resistant Gram-negative bacteria (27·2%, 17·6-36·8; I2 =94%). The pooled prevalence of any AMR carriage or infection was higher in refugees and asylum seekers (33·0%, 18·3-47·6; I2 =98%) than in other migrant groups (6·6%, 1·8-11·3; I2 =92%). The pooled prevalence of antibiotic-resistant organisms was slightly higher in high-migrant community settings (33·1%, 11·1-55·1; I2 =96%) than in migrants in hospitals (24·3%, 16·1-32·6; I2 =98%). We did not find evidence of high rates of transmission of AMR from migrant to host populations. INTERPRETATION: Migrants are exposed to conditions favouring the emergence of drug resistance during transit and in host countries in Europe. Increased antibiotic resistance among refugees and asylum seekers and in high-migrant community settings (such as refugee camps and detention facilities) highlights the need for improved living conditions, access to health care, and initiatives to facilitate detection of and appropriate high-quality treatment for antibiotic-resistant infections during transit and in host countries. Protocols for the prevention and control of infection and for antibiotic surveillance need to be integrated in all aspects of health care, which should be accessible for all migrant groups, and should target determinants of AMR before, during, and after migration. FUNDING: UK National Institute for Health Research Imperial Biomedical Research Centre, Imperial College Healthcare Charity, the Wellcome Trust, and UK National Institute for Health Research Health Protection Research Unit in Healthcare-associated Infections and Antimictobial Resistance at Imperial College London

Burnout among surgeons before and during the SARS-CoV-2 pandemic: an international survey

Background: SARS-CoV-2 pandemic has had many significant impacts within the surgical realm, and surgeons have been obligated to reconsider almost every aspect of daily clinical practice. Methods: This is a cross-sectional study reported in compliance with the CHERRIES guidelines and conducted through an online platform from June 14th to July 15th, 2020. The primary outcome was the burden of burnout during the pandemic indicated by the validated Shirom-Melamed Burnout Measure. Results: Nine hundred fifty-four surgeons completed the survey. The median length of practice was 10&nbsp;years; 78.2% included were male with a median age of 37&nbsp;years old, 39.5% were consultants, 68.9% were general surgeons, and 55.7% were affiliated with an academic institution. Overall, there was a significant increase in the mean burnout score during the pandemic; longer years of practice and older age were significantly associated with less burnout. There were significant reductions in the median number of outpatient visits, operated cases, on-call hours, emergency visits, and research work, so, 48.2% of respondents felt that the training resources were insufficient. The majority (81.3%) of respondents reported that their hospitals were included in the management of COVID-19, 66.5% felt their roles had been minimized; 41% were asked to assist in non-surgical medical practices, and 37.6% of respondents were included in COVID-19 management. Conclusions: There was a significant burnout among trainees. Almost all aspects of clinical and research activities were affected with a significant reduction in the volume of research, outpatient clinic visits, surgical procedures, on-call hours, and emergency cases hindering the training. Trial registration: The study was registered on clicaltrials.gov "NCT04433286" on 16/06/2020

Epidemiology of injuries from fire, heat and hot substances : global, regional and national morbidity and mortality estimates from the Global Burden of Disease 2017 study

Background Past research has shown how fires, heat and hot substances are important causes of health loss globally. Detailed estimates of the morbidity and mortality from these injuries could help drive preventative measures and improved access to care. Methods We used the Global Burden of Disease 2017 framework to produce three main results. First, we produced results on incidence, prevalence, years lived with disability, deaths, years of life lost and disability-adjusted life years from 1990 to 2017 for 195 countries and territories. Second, we analysed these results to measure mortality-to-incidence ratios by location. Third, we reported the measures above in terms of the cause of fire, heat and hot substances and the types of bodily injuries that result. Results Globally, there were 8 991 468 (7 481 218 to 10 740 897) new fire, heat and hot substance injuries in 2017 with 120 632 (101 630 to 129 383) deaths. At the global level, the age-standardised mortality caused by fire, heat and hot substances significantly declined from 1990 to 2017, but regionally there was variability in age-standardised incidence with some regions experiencing an increase (eg, Southern Latin America) and others experiencing a significant decrease (eg, High-income North America). Conclusions The incidence and mortality of injuries that result from fire, heat and hot substances affect every region of the world but are most concentrated in middle and lower income areas. More resources should be invested in measuring these injuries as well as in improving infrastructure, advancing safety measures and ensuring access to care.Peer reviewe