Achieving Optimal Throughput and Near-Optimal Asymptotic Delay Performance in Multi-Channel Wireless Networks with Low Complexity: A Practical Greedy Scheduling Policy

In this paper, we focus on the scheduling problem in multi-channel wireless networks, e.g., the downlink of a single cell in fourth generation (4G) OFDM-based cellular networks. Our goal is to design practical scheduling policies that can achieve provably good performance in terms of both throughput and delay, at a low complexity. While a class of $O(n^{2.5} \log n)$-complexity hybrid scheduling policies are recently developed to guarantee both rate-function delay optimality (in the many-channel many-user asymptotic regime) and throughput optimality (in the general non-asymptotic setting), their practical complexity is typically high. To address this issue, we develop a simple greedy policy called Delay-based Server-Side-Greedy (D-SSG) with a \lower complexity $2n^2+2n$, and rigorously prove that D-SSG not only achieves throughput optimality, but also guarantees near-optimal asymptotic delay performance. Specifically, we show that the rate-function attained by D-SSG for any delay-violation threshold $b$, is no smaller than the maximum achievable rate-function by any scheduling policy for threshold $b-1$. Thus, we are able to achieve a reduction in complexity (from $O(n^{2.5} \log n)$ of the hybrid policies to $2n^2 + 2n$) with a minimal drop in the delay performance. More importantly, in practice, D-SSG generally has a substantially lower complexity than the hybrid policies that typically have a large constant factor hidden in the $O(\cdot)$ notation. Finally, we conduct numerical simulations to validate our theoretical results in various scenarios. The simulation results show that D-SSG not only guarantees a near-optimal rate-function, but also empirically is virtually indistinguishable from delay-optimal policies.Comment: Accepted for publication by the IEEE/ACM Transactions on Networking, February 2014. A preliminary version of this work was presented at IEEE INFOCOM 2013, Turin, Italy, April 201

Suitable low Global Warming Potential (GWP) refrigerants for two-speed Heat Pumps for residential applications based on simulated performance

The next generation of heat pumps (HPs), including those intended for cold climates must transition to low-global warming potential (GWP) refrigerants to mitigate climate change. HPs must be designed to alleviate the problems of excessive discharge temperatures, low suction pressure and high-pressure ratio at low ambient conditions and insufficient heating capacity relative to the rated heating capacity. In this paper we recognize those concerns. Low global warming potential (GWP) refrigerants are screened based on the shape of their temperature-entropy (T-S) saturation boundary. Simulations of the two-stage HP with low GWP refrigerants (R32, R454B, R466A, and R452B) to replace R-410A was accomplished using the DOE/ORNL Heat Pump Design Model. Systemic inefficiency was addressed by component-level exergy analysis to refine design options. HPs with low-GWP refrigerants address issues of reducing energy consumption, lowering carbon footprint, and enabling environmental sustainability

Antibiotic prescribing in two private sector hospitals; one teaching and one non-teaching: A cross-sectional study in Ujjain, India

BACKGROUND: The worldwide increase in antibiotic resistant bacteria is of great concern. One of the main causes is antibiotic use which is likely to be high but is poorly described in India. The aim was to analyze and compare antibiotic prescribing for inpatients, in two private sector tertiary care hospitals; one Teaching and one Non-teaching, in Ujjain, India. METHODS: A cross-sectional study with manual data collection was carried out in 2008. Antibiotic prescribing was recorded for all inpatients throughout their hospital stay. Demographic profile of inpatients and prescribed antibiotics were compared. WHO Anatomical Therapeutic Chemical (ATC) classifications for antibiotics was used and Defined Daily Doses (DDD) were calculated per patient day. RESULTS: A total of 8385 inpatients were admitted during the study period. In the Teaching hospital (TH) 82% of 3004 and in the Non-teaching hospital (NTH) 79% of 5381 patients were prescribed antibiotics. The most commonly prescribed antibiotic groups were; fluoroquinolones and aminoglycosides in the TH and, 3rd generation cephalosporins and combination of antibiotics in the NTH. Of the prescriptions, 51% in the TH and 87% in the NTH (p<0.001) were for parenteral route administration. Prescribing by trade name was higher in the NTH (96%) compared with the TH (63%, p<0.001). CONCLUSIONS: The results from both hospitals show extensive antibiotic prescribing. High use of combinations of antibiotics in the NTH might indicate pressure from pharmaceutical companies. There is a need to formulate and implement; based on local prescribing and resistance data; contextually appropriate antibiotic prescribing guidelines and a local antibiotic stewardship program

Chitosan Encapsulation of Ferrateᵛᶦ for Controlled Release to Water: Mechanistic Insights and Degradation of Organic Contaminant

Tetraoxy-anion of iron in +6 oxidation state (FeVIO42−, FeVI) commonly called ferrate, has shown tremendous potential as a green oxidative agent for decontaminating water and air. Encapsulation of solid potassium salt of ferrate (K2FeO4) circumvents the inherent drawbacks of the instability of ferrate under humid conditions. In the encapsulated strategy, controlled release without exposing the solid ferrate to the humid environment avoids self-decomposition of the oxidant by water in the air, and the ferrate is mostly used to decontaminate water efficiently. This study demonstrated the formulation of oxidative microcapsules with natural materials present in chitosan, whose release rate of the core material can be controlled by the type of intermediate hydrocarbon layer and the pH-dependent swelling of chitosan shell. The pH played a pivotal role in swelling chitosan shell and releasing the core oxidant. In a strong acidic solution, chitosan tended to swell quickly and release FeVI at a faster rate than under neutral conditions. Additionally, among the several long-chain hydrocarbon compounds, oleic acid exhibited the strongest “locking” effect when applied as the intermediate layer, giving rise to the slow release of FeVI . Coconut oil and mineral oil, in comparison, allowed FeVI to penetrate the layer within shorter lengths of time and showed comparable degrees of degradation of target contaminant, methylene orange, under ambient temperature and near-neutral conditions. These findings have practical ramifications for remediating environmental and industrial processes

Lobariaceae from the Western Ghats of India

The lichen family Lobariaceae has 34 species represented in India. In this paper six new records are reported for the first time from different states of the Western Ghats: Lobaria adscripta (Nyl.) Hue, L. fuscotomentosa Yoshim, Pseudocyphellaria argyracea (Bory ex Delise) Vain, P. aurata (Sm. Ex. Ach.) Vain., P. crocata (L.) Vain. and Sticta duplolimbata (Hue) Vain. Of these, two are new records to Kerala, one new record to Karnataka, one to Kerala and Tamil Nadu each and Sticta duplolimbata (Hue) Vain. as new record to India (Tamil Nadu)

Minihepcidins are rationally designed small peptides that mimic hepcidin activity in mice and may be useful for the treatment of iron overload

Iron overload is the hallmark of hereditary hemochromatosis and a complication of iron-loading anemias such as β-thalassemia. Treatment can be burdensome and have significant side effects, and new therapeutic options are needed. Iron overload in hereditary hemochromatosis and β-thalassemia intermedia is caused by hepcidin deficiency. Although transgenic hepcidin replacement in mouse models of these diseases prevents iron overload or decreases its potential toxicity, natural hepcidin is prohibitively expensive for human application and has unfavorable pharmacologic properties. Here, we report the rational design of hepcidin agonists based on the mutagenesis of hepcidin and the hepcidin-binding region of ferroportin and computer modeling of their docking. We identified specific hydrophobic/aromatic residues required for hepcidin-ferroportin binding and obtained evidence in vitro that a thiol-disulfide interaction between ferroportin C326 and the hepcidin disulfide cage may stabilize binding. Guided by this model, we showed that 7–9 N-terminal amino acids of hepcidin, including a single thiol cysteine, comprised the minimal structure that retained hepcidin activity, as shown by the induction of ferroportin degradation in reporter cells. Further modifications to increase resistance to proteolysis and oral bioavailability yielded minihepcidins that, after parenteral or oral administration to mice, lowered serum iron levels comparably to those after parenteral native hepcidin. Moreover, liver iron concentrations were lower in mice chronically treated with minihepcidins than those in mice treated with solvent alone. Minihepcidins may be useful for the treatment of iron overload disorders

Fine-Grained Multivariate Time Series Anomaly Detection in IoT

Funding Information: Funding Statement: This work was supported in part by the National Natural Science Foundation of China under Grant 62272062, the Researchers Supporting Project number. (RSP2023R102) King Saud University, Riyadh, Saudi Arabia, the Open Research Fund of the Hunan Provincial Key Laboratory of Network Investigational Technology under Grant 2018WLZC003, the National Science Foundation of Hunan Province under Grant 2020JJ2029, the Hunan Provincial Key Research and Development Program under Grant 2022GK2019, the Science Fund for Creative Research Groups of Hunan Province under Grant 2020JJ1006, the Scientific Research Fund of Hunan Provincial Transportation Department under Grant 202143, and the Open Fund of Key Laboratory of Safety Control of Bridge Engineering, Ministry of Education (Changsha University of Science Technology) under Grant 21KB07. Publisher Copyright: © 2023 Tech Science Press. All rights reserved.Peer reviewedPublisher PD