399 research outputs found
Joint Scheduling of URLLC and eMBB Traffic in 5G Wireless Networks
Emerging 5G systems will need to efficiently support both enhanced mobile
broadband traffic (eMBB) and ultra-low-latency communications (URLLC) traffic.
In these systems, time is divided into slots which are further sub-divided into
minislots. From a scheduling perspective, eMBB resource allocations occur at
slot boundaries, whereas to reduce latency URLLC traffic is pre-emptively
overlapped at the minislot timescale, resulting in selective
superposition/puncturing of eMBB allocations. This approach enables minimal
URLLC latency at a potential rate loss to eMBB traffic.
We study joint eMBB and URLLC schedulers for such systems, with the dual
objectives of maximizing utility for eMBB traffic while immediately satisfying
URLLC demands. For a linear rate loss model (loss to eMBB is linear in the
amount of URLLC superposition/puncturing), we derive an optimal joint
scheduler. Somewhat counter-intuitively, our results show that our dual
objectives can be met by an iterative gradient scheduler for eMBB traffic that
anticipates the expected loss from URLLC traffic, along with an URLLC demand
scheduler that is oblivious to eMBB channel states, utility functions and
allocation decisions of the eMBB scheduler. Next we consider a more general
class of (convex/threshold) loss models and study optimal online joint
eMBB/URLLC schedulers within the broad class of channel state dependent but
minislot-homogeneous policies. A key observation is that unlike the linear rate
loss model, for the convex and threshold rate loss models, optimal eMBB and
URLLC scheduling decisions do not de-couple and joint optimization is necessary
to satisfy the dual objectives. We validate the characteristics and benefits of
our schedulers via simulation
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Schedulers for next generation wireless networks : realizing QoE trade-offs for heterogeneous traffic mixes
In this thesis we will focus on the design of schedulers for next generation wireless networks which support application mixes, characterized by different, possibly complex, application/user Quality of Experience (QoE) metrics. The central problem underlying resource allocation for such systems is realizing QoE trade-offs among various applications/users given the dynamic loads and capacity variability they would typically see. In the first part of the thesis our focus is on applications where QoE depends on flow-level delay-based metrics. We consider system-wide metrics which directly capture both users' QoE metrics and appropriate QoE trade-offs among various applications for a wide range of system loads. This approach is different from the traditional wireless scheduler designs which have been driven by rate-based criteria, e.g., utility maximizing/proportionally fair, and/or queue-based packet schedulers which do not directly reflect the link between flow-level delays and users' QoE. In the second part of this thesis we address the key design challenges in networks supporting Ultra Reliable Low Latency Communications (URLLC) traffic which requires extremely high reliability (99.999%) and very low delays (1 msec). We will explore three different types flow delay-based metrics in this proposal, based on 1) overall mean delay; 2) functions of mean delays; and, 3) mean of functions of delays. We begin by considering minimization of mean flow delay for an M/GI/1 queuing model for a wireless Base Station (BS) where the flow size distributions are of the New Better than Used in Expectation + Decreasing Hazard Rate (NBUE +DHZ) type. Such a flow size distribution have been observed in real systems and we too validate this model based on collected data. Using a combination of analysis and simulation we show that our scheduler achieves good performance for users that might correspond to interactive applications like web browsing and/or stored video streaming and is robust to variations in system loads. Next we consider a generalization of this approach where we minimize a metric based on cost functions of the mean flow delays in a multi-class system where users/flows are classified based on their respective QoE requirements and each class's QoE requirement is modeled by its respective cost function. This approach helps us model QoE more accurately and gives us more flexibility in considering QoE trade-offs among heterogeneous user classes. We optimize two different metrics based on how we average the cost functions of delays, namely, functions of mean delays; and mean of functions of delays. The former can be used when users' experiences are sensitive to mean delays and while the latter can be used when user's experience is also sensitive to higher moments of delays, e.g., variance or soft thresholds on delay. Extensive simulations confirm the effectiveness of our proposed approaches at realizing various QoE trade-offs and performance. In 5G wireless networks URLLC traffic is expected to support many applications like industrial automation, mission critical traffic, virtual traffic etc, where the wireless network has to reliability transport small packets with very high reliability and low delays. We address the following aspects related to the system design for URLLC traffic, 1) quantifying the impact of various system parameters like system bandwidth, link SINR, delay and latency constraints on URLLC 'capacity'; 2) provisioning wireless system appropriately to meet URLLC Quality of Service (QoS) requirements; and, 3) designing efficient Hybrid Automatic Repeat Request (HARQ) schemes for transmitting small packets. Further, due the heterogeneity in delay requirements between URLLC and other types of traffic, sharing radio resources between them creates its own unique challenges. We develop efficient multiplexing schemes between URLLC traffic and other mobile broadband traffic based on preemptive puncturing/superposition of the mobile broadband transmissions by URLLC transmissions.Electrical and Computer Engineerin
LYCOPENE IN THE MANAGEMENT OF ORAL SUBMUCOUS FIBROSIS
Background: Oral Submucous Fibrosis is a potentially malignant disorder well known for its chronic and resistant nature. The conservative drug treatment that is currently available for this disorder is clearly inadequate. The aim of the study was to evaluate the efficacy of oral lycopene therapy when used in combination with conventional intralesional steroid therapy in the management of oral submucous fibrosis. Methods: Forty five patients with oral submucous fibrosis (grade III and IV) were included under the study and were randomly divided into 3 groups consisting of 15 cases each: Group A (oral lycopene 16 mg/day with biweekly intralesional steroids and hyaluronidase), Group B (oral antioxidant capsules with biweekly intralesional steroids and hyaluronidase) and Group C (biweekly intralesional steroids and hyaluronidase alone). Mouth opening and burning sensation were recorded from baseline to 6 weeks. Cases were followed up to 3 and 6 months. Results: There was significant increase in mouth opening among all the 3 groups. The results were statistically significant between Group A and C and Group B and C. Conclusion: Lycopene in combination with intralesional steroids and Hyaluronidase, is highly efficacious in improving the mouth opening and reducing other symptoms in patients with Oral Submucous Fibrosis. No side effects were reported with its usage
Simple Methods to Represent Shapes with Sample Spheres
Representing complex shapes with simple primitives in high accuracy is
important for a variety of applications in computer graphics and geometry
processing. Existing solutions may produce suboptimal samples or are complex to
implement. We present methods to approximate given shapes with user-tunable
number of spheres to balance between accuracy and simplicity: touching
medial/scale-axis polar balls and k-means smallest enclosing circles. Our
methods are easy to implement, run efficiently, and can approach quality
similar to manual construction.Comment: SIGGRAPH Asia 2020 Technical Communication
Preserving the Native Valve: Does Valve-Sparing Repair Improve Outcomes in the Tetralogy of Fallot Repair?
Background: Tetralogy of Fallot (TOF), a complex congenital heart defect, often requires surgical intervention, and choosing the optimal approach is critical for long-term patient health. While individual studies have highlighted the potential benefits of valve-sparing surgeries, including improved cardiac function and reduced need for reintervention, no comprehensive systematic review has compared these outcomes directly with those of non-valve-sparing surgical techniques. This study aims to fill that gap by analyzing available evidence to provide clearer insights into the effectiveness and potential advantages of valve-sparing approaches thereby guiding clinical decision-making and improving surgical strategies for TOF patients.
Methods: Data collection was conducted using PubMed, PubMed Central, and Medline databases, adhering to PRISMA guidelines to ensure a rigorous and comprehensive review process. The search strategy incorporated Medical Subject Headings (MeSH) and key terms to identify relevant studies. Initially, seventy articles were identified, which were then screened based on their titles and abstracts. This process refined the selection to fifteen articles for full-text review, and ultimately, eight high-quality studies were included in the final analysis. Given the significant limitation of available high-quality clinical trials and prospective studies, we ensured that all selected papers met strict inclusion and exclusion criteria and passed quality checks. This systematic approach provides a solid foundation for analyzing and comparing surgical outcomes, contributing valuable insights to the field.
Results: This study analyzed data from 962 patients across eight studies, with 351 undergoing valve-sparing surgery and 611 receiving Tetralogy of Fallot (TOF) correction through non-valve-sparing methods. Based on the findings, preserving the native pulmonary valve, this approach promotes better growth and functionality of the valve over time. Additionally, valve-sparing surgery was associated with improved ventricular function in most studies, though findings on the need for reintervention were mixed. Importantly, the risk of complications appeared comparable between the two surgical modalities, yet valve-sparing repair consistently demonstrated superior overall outcomes. However, low birth weight remains a significant risk factor, even for valve-sparing procedures, highlighting the need for careful patient selection and management.
Conclusion: The evidence presented in the current study strongly supports the use of valve-sparing surgery for improved patient outcomes. The present study highlights the significant benefits of valve-sparing surgery over other surgical techniques, providing valuable insights that can inform clinical practice. By demonstrating its advantages, this project serves as a foundation for helping surgeons make more informed decisions regarding patient care
Bronchiectasis in India:results from the European Multicentre Bronchiectasis Audit and Research Collaboration (EMBARC) and Respiratory Research Network of India Registry
BACKGROUND: Bronchiectasis is a common but neglected chronic lung disease. Most epidemiological data are limited to cohorts from Europe and the USA, with few data from low-income and middle-income countries. We therefore aimed to describe the characteristics, severity of disease, microbiology, and treatment of patients with bronchiectasis in India. METHODS: The Indian bronchiectasis registry is a multicentre, prospective, observational cohort study. Adult patients ( 6518 years) with CT-confirmed bronchiectasis were enrolled from 31 centres across India. Patients with bronchiectasis due to cystic fibrosis or traction bronchiectasis associated with another respiratory disorder were excluded. Data were collected at baseline (recruitment) with follow-up visits taking place once per year. Comprehensive clinical data were collected through the European Multicentre Bronchiectasis Audit and Research Collaboration registry platform. Underlying aetiology of bronchiectasis, as well as treatment and risk factors for bronchiectasis were analysed in the Indian bronchiectasis registry. Comparisons of demographics were made with published European and US registries, and quality of care was benchmarked against the 2017 European Respiratory Society guidelines. FINDINGS: From June 1, 2015, to Sept 1, 2017, 2195 patients were enrolled. Marked differences were observed between India, Europe, and the USA. Patients in India were younger (median age 56 years [IQR 41-66] vs the European and US registries; p<0\ub70001]) and more likely to be men (1249 [56\ub79%] of 2195). Previous tuberculosis (780 [35\ub75%] of 2195) was the most frequent underlying cause of bronchiectasis and Pseudomonas aeruginosa was the most common organism in sputum culture (301 [13\ub77%]) in India. Risk factors for exacerbations included being of the male sex (adjusted incidence rate ratio 1\ub717, 95% CI 1\ub703-1\ub732; p=0\ub7015), P aeruginosa infection (1\ub729, 1\ub710-1\ub750; p=0\ub7001), a history of pulmonary tuberculosis (1\ub720, 1\ub707-1\ub734; p=0\ub7002), modified Medical Research Council Dyspnoea score (1\ub732, 1\ub725-1\ub739; p<0\ub70001), daily sputum production (1\ub716, 1\ub703-1\ub730; p=0\ub7013), and radiological severity of disease (1\ub703, 1\ub701-1\ub704; p<0\ub70001). Low adherence to guideline-recommended care was observed; only 388 patients were tested for allergic bronchopulmonary aspergillosis and 82 patients had been tested for immunoglobulins. INTERPRETATION: Patients with bronchiectasis in India have more severe disease and have distinct characteristics from those reported in other countries. This study provides a benchmark to improve quality of care for patients with bronchiectasis in India. FUNDING: EU/European Federation of Pharmaceutical Industries and Associations Innovative Medicines Initiative inhaled Antibiotics in Bronchiectasis and Cystic Fibrosis Consortium, European Respiratory Society, and the British Lung Foundation
Inferior conjunctival autografting for pterygium surgery: an alternative way of preserving the glaucoma filtration site in far western Nepal
Probiotic Characterization of Cholesterol-Lowering Saccharomyces cerevisiae Isolated from Frass of Pyrrharctia isabella Caterpillars
Background and Objectives: Cholesterol hyper-accumulation is a growing factor causing cardiovascular diseases (CVD), a leading cause of global mortality and accounts for 16.7 million deaths worldwide. As far as India is concerned, there is an increase from 25.7 to 54.7 million cases of CVD per year since the year 1990, and change in the dietary pattern being the major cause of this condition. Amongst, coronary heart disease and atherosclerosis remain prominent with its major causative agent as high cholesterol levels. However, the current treatment of these diseases is inadequate, and impose systemic toxicity such as stent thrombosis, chronic inflammation, etc., probiotics with cholesterol-lowering ability is an ideal and safe choice for the prevention of the condition.
Materials and Methods: The present study involved the culture-dependent method for the enumeration of microorganisms from caterpillar frass. Upon microscopic screening, yeast isolates were further characterized for their in-vitro probiotic potential such as toxicity assessment, tolerance to pH, bile, temperature, and salt conditions, safety assessment by measuring antibiotics susceptibility, evaluating antagonistic activity, assessing survival in simulated gastrointestinal environment, measuring aggregation capability, evaluating cholesterol-lowering activity and identifying microorganisms using molecular identification tools.
Results and Conclusion: The culture-dependent approach resulted in the isolation of four yeast cultures from the frass of Pyrrharctia isabella caterpillar. Yeast cultures designated as CP-I, CP-II, CP-III, and CP-IV were resistant for bile (1.2%), wide range of pH (1.5–10), and up to 42ºC temperature along with antimicrobial activity. CP-I culture also possessed bile salt hydrolase while tolerated stressful salt conditions, gastrointestinal environment, and exhibited good aggregation properties and hydrophobicity. Interestingly, CP-I could reduce cholesterol levels by 9.16% under in-vitro conditions. Molecular identification of CP-I showed its genetic similarity 97% with Saccharomyces cerevisiae. This study demonstrated for the first-time isolation of cholesterol-lowering probiotic yeast Saccharomyces cerevisiae from caterpillar frass in in-vitro conditions
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