69 research outputs found

    Network virtualization in next-generation cellular networks: a spectrum pooling approach

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    The hardship of expanding the cellular network market results from the tremendous high cost of mobile infrastructure, i.e. the capital expenditures (CAPEX) and the operational expenditures (OPEX). Spectrum Sharing is one of the proposed solution for the high-cost of scalability of cellular networks. However, most of the proposed spectrum pooling frameworks in the literature are mostly approached from a technical view besides there are no good cost models based on real datasets for quantifying the circumstances under which sharing the spectrum and network resources would be beneficial to mobile operators. In this thesis, by studying different sharing scenarios in a fiber-based backhaul mobile network, we assess the incentives for service providers (SPs) to share spectrum/infrastructure in different cellular market areas/economic areas (CMA/BEAs) with different population density, allocated bandwidth (BW), spectrum bid values and considering different network topologies. Moreover, we look at the technical problem of sharing the spectrum between two SPs sharing the same basestation (BS), yet they have different traffic demand as well as different QoS constraints. We design a resource allocation scheme to provision real-time (RT), non-real-time (NRT) as well as Ultra-reliable Low Latency Communications (URLLC) traffic in a single shared BS scenario such that SPs achieve isolation, fairness and enforce their QoS constraints. Finally, we exploit spectrum pooling to develop an approach for dynamically re-configuring the base stations that survive a disaster and are powered by a microgrid to form a multi-hop mesh network in order to provide local cellular service

    Resource Scheduling For Heterogeneous Traffic in LTE Virtual Networks

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    Abstract-Cellular network virtualization is being considered as a key trend in future mobile networks towards improved resource utilization. However, virtualization scenarios need investigation to understand the considerations which should be taken into account when deploying virtualized wireless networks in practice. Towards this, we address the performance of a virtualized network in the presence of heterogeneous classes of traffic. In previous cellular network virtualization literature, both Realtime (RT) and Non-Realtime (NRT) traffic requests have been included without distinction. Both types are provisioned using the same algorithm for allocation of resources specified by the Network Scheduler [1]. However, different types of traffic have different characteristics [2], e.g., RT requests are delay sensitive but may need fixed bandwidth, and hence should be treated differently, especially when wireless channel conditions are factored into the scheduling. We recognize this difference and in this paper, we propose a new approach to improve scheduling of resources for RT and NRT traffic. In particular, we prioritize the traffic belonging to different virtual slices from all service providers (SP/VEs) at the Network Scheduler before allocating resources to different SP/VEs, i.e., we form a Virtual Prioritized Slice (VPS). The virtual prioritized slice is forwarded to the VPS scheduler to serve all RT requests first. Only after the RT traffic is scheduled, the NRT traffic is provisioned using proportional fairness (PF) scheduling. We show by simulation results that this new VPS approach helps outperform recently proposed resource allocation schemes

    The impact of paracentesis flow rate in patients with liver cirrhosis on the development of paracentesis induced circulatory dysfunction

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    Background/AimsAscites is a dreadful complication of liver cirrhosis associated with short survival. Large volume paracentesis (LVP) is used to treat tense or refractory ascites. Paracentesis induced circulatory dysfunction (PICD) develops if no plasma expanders are given with ominous complications. To study the effect of ascites flow rate on PICD development.MethodsSixty patients with cirrhosis and tense ascites underwent LVP of 8 L were randomized into 3 equal groups of different flow rate extraction; group I (80 mL/minute), group II (180 mL/minute) and group III (270 mL/minute). Plasma renin activity (PRA) was measured baseline and on day six. PICD was defined as increase in PRA >50% of the pretreatment value.ResultsIn group I through 3; the mean age was (52.5±9.4 vs. 56.4±8.5 vs. 55.8±7.1 years; P>0.05), mean arterial pressure (81.4±5.6 vs. 81.5±7 vs. 79.5±7.2 mmHg; P>0.05), MELD (17.6±4.1 vs. 15.8±4.1 vs. 14.7±4.5). Baseline PRA was comparable (1,366.0±1244.9 vs. 1,151.3±1,444.8 vs. 951.9±1,088 pg/mL; P>0.05). There was no statistically significant (P>0.05) flow mediated changes (Δ) of creatinine (0.23±0.27 vs. 0.38±0.33 vs. 0.26±0.18 mg/dL), MELD (1.25±5.72 vs. 1.70±2.18 vs. 1.45±2.21) or PRA (450.93±614.10 vs. 394.61±954.64 vs. 629.51±1,116.46 pg/mL). PICD was detected in a similar frequency in the three groups (P>0.05). On univariate logistic analysis only female sex was a fairly significant PICD predictor (Wald 3.85, odds ratio 3.14; P=0.05).ConclusionsThe ascites flow rate does not correlate with PICD development

    Prognosis of Human Cytomegalovirus in Cancer Patients Undergoing Chemotherapeutic Treatment in Egypt and an Emergent Prevalence of Glycoprotein B-5

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    The human cytomegalovirus (HCMV) is a global opportunistic β-herpes virus causing severe diseases in immune-compromised patients, such as malignant tumor patients, especially those undergoing chemotherapeutic treatment. This study aimed to determine the prevalence of HCMV-DNA in chemotherapeutic treatment naive cancer patients, and after chemotherapy, to compare between conventional nested PCR and ELISA techniques for the detection of HCMV, and to detect glycoprotein B genotypes. Plasma and serum samples before and after three chemotherapy cycles were collected from 49 chemotherapy-naive cancer patients. DNA was extracted from plasma samples using QIAamp® DNA Mini kit. HCMV-DNA was detected using a nested PCR technique. Multiplex nested PCR was used for HCMV-glycoprotein B (gB) genotyping. HCMV-IgG and -IgM were detected using ELISA technique. Thirty one (63.3 %) of the 49 plasma samples of the chemotherapy-naïve cancer patients were positive for HCMV-DNA; 21 of which remained positive after chemotherapy. However, 18 samples were negative of which 16 became positive after chemotherapy. gB-5 was the most common glycoprotein genotype detected (80.6 %), followed by gB-1, gB-3, gB-4, and gB-2. HCMV IgG was detected in the 49 serum samples of chemotherapy-naïve patients, and after exposure to chemotherapy. HCMV-DNA is commonly identified in cancer patients. Its detection after chemotherapy exposure may suggest HCMV reactivation. The most common genotype detected in cancer patients in Egypt is gB-5 in contrast to earlier research. IgG was detected in all patients. This indicates that HCMV is endemic in Egypt, necessitating the development of public awareness campaigns about HCMV infection and preventive strategies

    Phytohormones as Growth Regulators During Abiotic Stress Tolerance in Plants

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    Phytohormones (PHs) play crucial role in regulation of various physiological and biochemical processes that govern plant growth and yield under optimal and stress conditions. The interaction of these PHs is crucial for plant survival under stressful environments as they trigger signaling pathways. Hormonal cross regulation initiate a cascade of reactions which finely tune the physiological processes in plant architecture that help plant to grow under suboptimal growth conditions. Recently, various studies have highlighted the role of PHs such as abscisic acid, salicylic acid, ethylene, and jasmonates in the plant responses toward environmental stresses. The involvement of cytokinins, gibberellins, auxin, and relatively novel PHs such as strigolactones and brassinosteroids in plant growth and development has been documented under normal and stress conditions. The recent identification of the first plant melatonin receptor opened the door to this regulatory molecule being considered a new plant hormone. However, polyamines, which are not considered PHs, have been included in this chapter. Various microbes produce and secrete hormones which helped the plants in nutrient uptake such as N, P, and Fe. Exogenous use of such microbes help plants in correcting nutrient deficiency under abiotic stresses. This chapter focused on the recent developments in the knowledge related to PHs and their involvement in abiotic stresses of anticipation, signaling, cross-talk, and activation of response mechanisms. In view of role of hormones and capability of microbes in producing hormones, we propose the use of hormones and microbes as potential strategy for crop stress management.Fil: EL Sabagh, Ayman. Scientific And Technological Research Council Of Turkey; TurquíaFil: Islam, Mohammad Sohidul. Kafrelsheikh University; EgiptoFil: Hossain, Akbar. Hajee Mohammad Danesh And Technology University; BangladeshFil: Iqbal, Muhammad Aamir. University Of Poonch; PakistánFil: Mubeen, Mohammad. Comsats University Islamabad; PakistánFil: Waleed, Mirza. Comsats University Islamabad; PakistánFil: Reginato, Mariana Andrea. Universidad Nacional de Río Cuarto. Facultad de Ciencias Exactas Fisicoquímicas y Naturales. Instituto de Investigaciones Agrobiotecnológicas. - Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Investigaciones Agrobiotecnológicas; ArgentinaFil: Battaglia, Martin. Cornell University; Estados UnidosFil: Ahmed, Sharif. International Rice Research Institute; FilipinasFil: Rehman, Abdul. The Islamia University Of Bahawalpur; PakistánFil: Arif, Muhammad. The University Of Agriculture; PakistánFil: Athar, Habib-Ur-Rehman. Bahauddin Zakariya University; PakistánFil: Ratnasekera, Disna. University Of Ruhuna; Sri LankaFil: Danish, Subhan. Bahauddin Zakariya University; PakistánFil: Raza, Ali. Sichuan Agricultural University; ChinaFil: Rajendran, Karthika. Vellore Institute Of Technology; IndiaFil: Mushtaq, Muntazir. Icar-national Bureau Of Plant Genetic Resources; IndiaFil: Skalicky, Milan. Czech University Of Life Sciences Prague; República ChecaFil: Brestic, Marian. Czech University Of Life Sciences Prague; República ChecaFil: Soufan, Walid. King Saud University; Arabia SauditaFil: Fahad, Shah. University Of Haripur; PakistánFil: Pandey, Saurabh. Guru Nanak Dev University; IndiaFil: Abdelhamid, Magdi T.. National Research Centre Dokki; Egipt

    Safety and efficacy of percutaneous nephrolithotripsy in comorbid patients: A 3 years prospective observational study

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    Purpose: To report the result of percutaneous nephrolithotripsy (PCNL) via standard nephrostomy tract in a single training institution. The perioperative complications in relation to the comorbid state are particularly assessed. Patients and methods: A prospective interventional study between January 2019 to November 2022, included 210 patients scheduled for PCNL. The average age was 40.3 ± 11.8 years (range 18- 67 years). Patients were categorized into two groups. The first group comprised 146 cases (69 .5%) with no associated co-morbidities while the second group 64 (30.5%) had co-morbidities such as obesity in 4 cases (1.9%), hypertension (HTN) in 24 cases (11.4%) cases, diabetes mellitus (DM) in 17 (8.1%) cases, history of recurrent stone surgery in 11 (5.2%) cases and more than one in 8 cases (3.8%). Co-morbidities, stone burden, location of stone, time of surgery, stay in the hospital, further operations, and negative events were among the reported data. Complications and the stone-free rate were the main outcome indicators. Results: Intraoperative complications were reported in 40 (18.8%) patients (18 group 1 and 22 group 2) during PCNL. Bleeding occurred in 22 (10.5%) patients (9 group 1 and 13 group 2), blood transfusions were needed in 4 (1.9%) (2 group 1 and 2 group 2), extravasation was observed in 11 patients (5.2%) (6 group 1 and 5 group 2) and cardiac arrhythmia in 3 (1.4%) (1 group 1 and 2 group 2) patients. Postoperative complications occurred in 61 patients (29%) (24 group 1 and 37 group 2) in the form of fever in 10 patients (4.8 %) (3 group 1 and 7 group 2) and prolonged leakage in 50 patients (23.8%) (21 group 1 and 29 group 2). One patient of group 2 died from postoperative sepsis. Extravasation and postoperative leakage were higher in diabetic patients than in non-diabetics. Stonefree rate was 60.5% (127 of 210). Clinically significant residual fragments (CSRFs) found in 70 cases (33.3%) (33 group 1 and 37 group 2). In 13 cases (6.2%) (5 group 1 and 8 group 2), clinically insignificant residual fragments (CIRFs) were found. In 8 (3 group 1 and 5 group 2) of the 13 cases, spontaneous stone passage was observed within 4-6 weeks of surgery. Residual stones in three cases (1 group 1 and 2 group 2) were asymptomatic and 4 mm or less, whereas stones increased in two cases of group 2. Among all factors studied, stone burden was significantly correlated to both intraoperative and postoperative complications. The occurrence of postoperative fever increased with large stone burden. Conclusions: PCNL is a therapeutic modality that is effective, feasible, and safe for a wide range of patients with concurrent medical issues. A steep curve is required to reduce intraoperative and postoperative complications

    Evaluation of Rezum therapy as a minimally invasive modality for management of Benign Prostatic Hyperplasia: A prospective observational study

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    Objective: To evaluate safety and efficacy of Rezum therapy as a minimally invasive modality for management of benign prostatic hyperplasia in patients with prostate volume 80cc. Methods: Between June 2020 and February 2023, A total of 98 patients diagnosed with BPH and managed by Rezum were included in this study. Patients were divided based on their prostate volume of either less than 80 cc or greater than 80 cc. We evaluated several parameters related to their condition, including prostate volume, post-voiding residual (PVR) before and after surgery, number of treatments received, maximum urine flow rate (Qmax) before and after surgery and mean follow- up periods. Results: The mean age was 68 years (SD 11.2). The median prostatic volume was 62 cc (IQR 41, 17). A maximum of 9 treatments were administered. Six months was determined to be the average post-operative follow-up period (IQR: 3.5-7.2). The mean preoperative total PSA was 2.7 (IQR 1, 2), preoperative mean PVR was 79.8 cm3, preoperative mean Qmax was 8.2 ml/s (IQR 4.7-10.5), and median post-operative days until catheter removal was four days (IQR 3,1). Post-operative PVR was 24.7 cm3 (IQR 18.2, 29.4) and the mean post-operative Qmax was 18.3 ml/s (SD 6.3). Qmax levels significantly increased, by an average of 8.2 ml/s (SD 7.13) (p < 0.001). Similarly, a decrease of average PVR of 97.28 cm3 (SD 95.85) (p < 0.001) was detected, which is a substantial reduction. Between prostates less 80cc and those over 80cc, there were no appreciable differences in Qmax or PVR (p-values: 0.435 and 0.431, respectively). Conclusions: From our study, we conclude that Rezum water vapor thermal therapy, as a minimally invasive modality, is an effective and safe surgical option for management of benign prostatic hyperplasia of men with moderate to severe lower urinary tract symptoms (LUTS). This procedure has been shown to be effective in patients with varying larger prostate volumes

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

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    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

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    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

    Surgical site infection after gastrointestinal surgery in high-income, middle-income, and low-income countries: a prospective, international, multicentre cohort study

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    Background: Surgical site infection (SSI) is one of the most common infections associated with health care, but its importance as a global health priority is not fully understood. We quantified the burden of SSI after gastrointestinal surgery in countries in all parts of the world. Methods: This international, prospective, multicentre cohort study included consecutive patients undergoing elective or emergency gastrointestinal resection within 2-week time periods at any health-care facility in any country. Countries with participating centres were stratified into high-income, middle-income, and low-income groups according to the UN's Human Development Index (HDI). Data variables from the GlobalSurg 1 study and other studies that have been found to affect the likelihood of SSI were entered into risk adjustment models. The primary outcome measure was the 30-day SSI incidence (defined by US Centers for Disease Control and Prevention criteria for superficial and deep incisional SSI). Relationships with explanatory variables were examined using Bayesian multilevel logistic regression models. This trial is registered with ClinicalTrials.gov, number NCT02662231. Findings: Between Jan 4, 2016, and July 31, 2016, 13 265 records were submitted for analysis. 12 539 patients from 343 hospitals in 66 countries were included. 7339 (58·5%) patient were from high-HDI countries (193 hospitals in 30 countries), 3918 (31·2%) patients were from middle-HDI countries (82 hospitals in 18 countries), and 1282 (10·2%) patients were from low-HDI countries (68 hospitals in 18 countries). In total, 1538 (12·3%) patients had SSI within 30 days of surgery. The incidence of SSI varied between countries with high (691 [9·4%] of 7339 patients), middle (549 [14·0%] of 3918 patients), and low (298 [23·2%] of 1282) HDI (p < 0·001). The highest SSI incidence in each HDI group was after dirty surgery (102 [17·8%] of 574 patients in high-HDI countries; 74 [31·4%] of 236 patients in middle-HDI countries; 72 [39·8%] of 181 patients in low-HDI countries). Following risk factor adjustment, patients in low-HDI countries were at greatest risk of SSI (adjusted odds ratio 1·60, 95% credible interval 1·05–2·37; p=0·030). 132 (21·6%) of 610 patients with an SSI and a microbiology culture result had an infection that was resistant to the prophylactic antibiotic used. Resistant infections were detected in 49 (16·6%) of 295 patients in high-HDI countries, in 37 (19·8%) of 187 patients in middle-HDI countries, and in 46 (35·9%) of 128 patients in low-HDI countries (p < 0·001). Interpretation: Countries with a low HDI carry a disproportionately greater burden of SSI than countries with a middle or high HDI and might have higher rates of antibiotic resistance. In view of WHO recommendations on SSI prevention that highlight the absence of high-quality interventional research, urgent, pragmatic, randomised trials based in LMICs are needed to assess measures aiming to reduce this preventable complication
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