Design and implementation of a QoS-aware communication protocol for named data networks

In the recent decade, a significant discrepancy has been identified between the IP-based Internet architecture and its primary use. Despite being fundamentally designed for facilitating ubiquitous interconnectivity between communication endpoints, the TCP/IP protocol suite is overwhelmingly used for content distribution. In fact, the IP-based architecture has several limitations when dealing with large-scale content distribution, including multicasting efficiency, handshaking overhead, mobility, routing scalability, and security. These limitations, facing the IP paradigm, have fostered the design of novel Internet architectures to meet the accelerating expansion in consumer Internet traffic. Named Data Networking (NDN) is a data-centric Internet architecture solution. It has recently received much attention as an efficient alternative Internet architecture to the IP-based Internet architecture. Generally, NDN represents a clean-slate receiver-oriented design which utilizes the Interest/Data model to retrieve data from possible source nodes [ZAB+14]. NDN architecture is based on four main concepts: content forwarding, in-network caching, multicasting, and built-in security at the data level. In-network caching and multipath forwarding strategies are the two significant features of NDN architecture. Content forwarding directly leverages data names—that carry application semantics - to exchange two types of packets, i.e. Interest and Data. In fact, the current routing algorithms of NDN networks do not make use of the unique NDN primitives, such as in-network caching and multipath forwarding. Therefore, this thesis is devoted to the development of a novel routing algorithm that improves the performance of NDN networking in terms of overall network resource-usage efficiency, data retrieval delay, and bandwidth. Aside from routing, the caching strategy of NDN networks completely ignores the topology structure of the network, thus the cache memories are exhausted in vain. Accordingly, a challenge of improving the routing strategy together with increasing the caching efficiency emerges. To tackle this challenge, three different methods to optimize the performance of the current caching capability and the forwarding mechanism of NDN are proposed, namely the Hop Distance Aware Caching (HDAC) strategy, the Segmented Data Aware Routers (SDAR) method, and the Knowledge Sharing-Based Forwarding (KSBF) strategy. The purposed KSBF strategy employs statistical information shared by neighbor routers and makes a forwarding decision for an Interest packet based on this knowledge. In other words, each NDN router selects the next hop based on what is called the “most probable path” rather than the best path determined by computing the Dijkstra algorithm. The process of sharing of statistical information is mainly controlled by the NDN forwarding mechanism. The SDAR method focuses on reducing the segmented data retrieval latency. In addition, a novel caching policy, i.e. HDAC strategy, is proposed to make a decision of whether to store the incoming packets in the memory based on the distance between the various NDN routers. Through evaluating the performance of the proposed methods, it is found that they significantly reduce the data retrieval time, the total resource usage and the overall bandwidth consumption

GÖRSEL BİR İMAJ VE MEKÂN METAFORUNUN KAYNAĞI OLARAK BAHAR

Yaygın kullanımında bir mevsime karşılık gelen bahar sözcüğü, klâsik Türk şiirinde çiçek, yaprak, yüz ve yanak anlamlarının yanı sıra put, tapınak ve kiliseyi de karşılamaktadır. Sözcüğün bu çok çeşitli kullanımlarında görsel bir tasviri ifade arayışı göze çarpmaktadır. Klâsik Türk şiirinde güzellik unsurlarının bir mekân estetiğinin yansımalarından doğduğu söylenebilir. Baharın lügatlerdeki karşılığına ve örnek metinlerde kullanımına bakıldığında, sözcüğün aslında mekânı ifade eden bir kavramken zamanla o mekânın niteliklerine benzer özellikler gösteren başka bir anlamsal forma dönüştüğü görülecektir. Hristiyanlara ait mabetlerde de tapınaklarda olduğu gibi resim ve putların bulunması, kilisenin klâsik Türk edebiyatında bahar sözcüğüyle karşılanmasına neden olmuştur, denebilir. Şiirlerde görsel bir imaj öne çıkarılmak istendiğinde kilisenin (deyr), sahip olduğu resim ve süslemeler sebebiyle bir istiare olarak dış mekânın ifadesinde kullanıldığı görülmektedir

Evaluation of Sleep Quality in Pregnancy According to Trimesters and Investigation of Related Factors

Objective:Pregnancy causes changes in the duration and quality of sleep. Insomnia, insufficient sleep time, and symptoms associated with restless legs syndrome/Willis-Ekbom disease (RLS/WED) are frequently described during pregnancy. We aimed to evaluate the deterioration in sleep quality during pregnancy according to trimesters and to examine the effect of RLS/WEH and its correlation with clinical and biochemical markers.Materials and Methods:Hundred pregnant women were included in the study prospectively and consecutively. Pregnant women were evaluated to determine their clinical characteristics, including demographic data, habits, and medical backgrounds by using a questionnaire. Pittsburgh Sleep Quality Index (PSQI), Epworth Sleepiness Scale (ESS), disease duration, severity, triggering factors, and family history for RLS/WEH were recorded. Complete blood count, fasting blood glucose, kidney function tests, ferritin, iron and iron binding capacity were also analyzed.Results:The mean age was 28.8±6.0 years. PSQI values were significantly higher in the third trimester (p=0.044), and ESS values were similar between trimesters (p=0.524). RLS/WEH was detected in 34% of the pregnant women; there was no difference between trimesters (p=0.188). The PSQI score was significantly higher in RLS/WEH patients (p=0.013). There was no significant difference in clinical and biochemical parameters between pregnant women with and without subjective poor sleep quality at night (PSQI >5 points).Conclusion:It is shown that night sleep quality is deteriorated in pregnant women, especially in the last trimester. The fact that the frequency of RLS/WEH is not different in pregnant women with poor sleep quality suggests the existence of other factors underlying poor sleep quality

Missed Gallstones in the Bile Duct and Abdominal Cavity: A Case Report

WOS: 000258504600027PubMed: 1871977

Systemic Immune Inflammation-Index and CANLPH Score in Patients with Mitral Stenosis Undergoing Balloon Valvuloplasty

Objective: to evaluate CANLPH score and systemic immune inflammation index (SII) in patients with symptomatic rheumatic mitral stenosis (MS) undergoing percutaneous mitral balloon valvuloplasty (PMBV). Methods: 62 patients who underwent PMBV in our clinic between 2018 and 2021 were included retrospectively. The patients were divided into 2 groups according to echo score. The CANLPH score was calculated from the cut-off values of C-reactive protein to albumin ratio (CAR), neutrophil to lymphocyte ratio (NLR) and platelet to hemoglobin ratio (PHR), determined with the Youden index and SII by the formula platelet x neutrophil/lymphocyte. P \u3c0.05 was considered statistically significant. Results: The mean age of the patients was 44.5±10.4 years (40 female, 64.5%). The mean values of SII and CANLPH scores were higher in the Echo score \u3e8 group (p \u3c0.001, both). The mean mitral gradient before and after PMBV was 12.6±5.7mm Hg and 5.0±2.4 mm Hg, and the mean valve area was 1.12±0.27 cm2 and 1.85±0.29 cm2. A statistically significant and negative correlation was observed between the gradient decrease after the procedure and the CANLPH score and SII (r=-0.426, p=0.001 and r=-0.418, p=0.001, respectively). In receiver operating characteristic (ROC) curve analysis, it was concluded that the ability of CANPLH score to predict the higher Echo scores was noninferior to SII with an area under curve (AUC:0.820 (0.701-0.906) and AUC:0.786 (0.664-0.880), z statistics 0.576 and p=0.564. Conclusion: SII and CANLPH scores are correlated with Echo score. A significant negative relationship was found with both biomarkers and gradient decrease after the PMBV

Epidemiology of surgery associated acute kidney injury (EPIS-AKI): a prospective international observational multi-center clinical study

Purpose: The incidence, patient features, risk factors and outcomes of surgery-associated postoperative acute kidney injury (PO-AKI) across different countries and health care systems is unclear. Methods: We conducted an international prospective, observational, multi-center study in 30 countries in patients undergoing major surgery (> 2-h duration and postoperative intensive care unit (ICU) or high dependency unit admission). The primary endpoint was the occurrence of PO-AKI within 72 h of surgery defined by the Kidney Disease: Improving Global Outcomes (KDIGO) criteria. Secondary endpoints included PO-AKI severity and duration, use of renal replacement therapy (RRT), mortality, and ICU and hospital length of stay. Results: We studied 10,568 patients and 1945 (18.4%) developed PO-AKI (1236 (63.5%) KDIGO stage 1500 (25.7%) KDIGO stage 2209 (10.7%) KDIGO stage 3). In 33.8% PO-AKI was persistent, and 170/1945 (8.7%) of patients with PO-AKI received RRT in the ICU. Patients with PO-AKI had greater ICU (6.3% vs. 0.7%) and hospital (8.6% vs. 1.4%) mortality, and longer ICU (median 2 (Q1-Q3, 1-3) days vs. 3 (Q1-Q3, 1-6) days) and hospital length of stay (median 14 (Q1-Q3, 9-24) days vs. 10 (Q1-Q3, 7-17) days). Risk factors for PO-AKI included older age, comorbidities (hypertension, diabetes, chronic kidney disease), type, duration and urgency of surgery as well as intraoperative vasopressors, and aminoglycosides administration. Conclusion: In a comprehensive multinational study, approximately one in five patients develop PO-AKI after major surgery. Increasing severity of PO-AKI is associated with a progressive increase in adverse outcomes. Our findings indicate that PO-AKI represents a significant burden for health care worldwide

EPIdemiology of Surgery-Associated Acute Kidney Injury (EPIS-AKI) : Study protocol for a multicentre, observational trial

More than 300 million surgical procedures are performed each year. Acute kidney injury (AKI) is a common complication after major surgery and is associated with adverse short-term and long-term outcomes. However, there is a large variation in the incidence of reported AKI rates. The establishment of an accurate epidemiology of surgery-associated AKI is important for healthcare policy, quality initiatives, clinical trials, as well as for improving guidelines. The objective of the Epidemiology of Surgery-associated Acute Kidney Injury (EPIS-AKI) trial is to prospectively evaluate the epidemiology of AKI after major surgery using the latest Kidney Disease: Improving Global Outcomes (KDIGO) consensus definition of AKI. EPIS-AKI is an international prospective, observational, multicentre cohort study including 10 000 patients undergoing major surgery who are subsequently admitted to the ICU or a similar high dependency unit. The primary endpoint is the incidence of AKI within 72 hours after surgery according to the KDIGO criteria. Secondary endpoints include use of renal replacement therapy (RRT), mortality during ICU and hospital stay, length of ICU and hospital stay and major adverse kidney events (combined endpoint consisting of persistent renal dysfunction, RRT and mortality) at day 90. Further, we will evaluate preoperative and intraoperative risk factors affecting the incidence of postoperative AKI. In an add-on analysis, we will assess urinary biomarkers for early detection of AKI. EPIS-AKI has been approved by the leading Ethics Committee of the Medical Council North Rhine-Westphalia, of the Westphalian Wilhelms-University Münster and the corresponding Ethics Committee at each participating site. Results will be disseminated widely and published in peer-reviewed journals, presented at conferences and used to design further AKI-related trials. Trial registration number NCT04165369

Reducing the environmental impact of surgery on a global scale: systematic review and co-prioritization with healthcare workers in 132 countries

Abstract Background Healthcare cannot achieve net-zero carbon without addressing operating theatres. The aim of this study was to prioritize feasible interventions to reduce the environmental impact of operating theatres. Methods This study adopted a four-phase Delphi consensus co-prioritization methodology. In phase 1, a systematic review of published interventions and global consultation of perioperative healthcare professionals were used to longlist interventions. In phase 2, iterative thematic analysis consolidated comparable interventions into a shortlist. In phase 3, the shortlist was co-prioritized based on patient and clinician views on acceptability, feasibility, and safety. In phase 4, ranked lists of interventions were presented by their relevance to high-income countries and low–middle-income countries. Results In phase 1, 43 interventions were identified, which had low uptake in practice according to 3042 professionals globally. In phase 2, a shortlist of 15 intervention domains was generated. In phase 3, interventions were deemed acceptable for more than 90 per cent of patients except for reducing general anaesthesia (84 per cent) and re-sterilization of ‘single-use’ consumables (86 per cent). In phase 4, the top three shortlisted interventions for high-income countries were: introducing recycling; reducing use of anaesthetic gases; and appropriate clinical waste processing. In phase 4, the top three shortlisted interventions for low–middle-income countries were: introducing reusable surgical devices; reducing use of consumables; and reducing the use of general anaesthesia. Conclusion This is a step toward environmentally sustainable operating environments with actionable interventions applicable to both high– and low–middle–income countries