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Cytokine storm an uncontrolled over-production of soluble markers of inflammation which is systemic inflammatory response, is a major responsible for the occurrence of ARDS. Animal studies that have implicated ACE2 in the acute lung injury caused due to SARSCoV. It has been hypothesized that ACE2 causes ALI by bringing about autophagy through the AMPK/mTOR pathway. Metformin works through AMPK activation, which leads to phosphorylation of ACE2 and there is an structural change which unables SARS CoV2 to bind with it also it is known that metformin can reduce CRP level.This study aim to find the role of metformin in COVID 19 on disease regression by both clinical assessment and laboratory values.Single blinded randomised controlled trial, parallel group, placebo controlled study for 1 month duration at tertiary health care centre. There is significant clinical improvement in 69% of the subjects at day 6 and 31% at day 7 in metformin group. Also there is effective reduction in CRP level whereas Sr.Ferritin levels are moderately reduced. There is no adverse effect during study period.

In this paper, a Modified Adaptive Cluster-Based Heuristic Approach (MACHBA) has been proposed for wireless sensor networks (WSNs) to perform the cooperative spectrum sensing (CSS) in the shopping mall, weather forecasting, military area and audio, video transmission applications. A Secure CSS based MACBHA has been proposed for secondary spectrum usage. Unlicensed Secondary Users (SUs) utilize parts of the spectrum, which are not used by the licensed primary users (PUs) in cognitive radio WSNs. The unused spectrum of the PUs is utilized by the secondary user cluster. The performance of the MACBHA in WSNs is evaluated using the network simulator tool NS-2.35 in Ubuntu 16.04.6 LTS (Xenial Xerus) operating system. The simulation result shows the performance improvement in network utility. Even though, the number of SUs increases, a minimum latency is achieved.

The usage of non linear loads in recent days are becoming vast that gives an alarm signal to power system and power engineers in terms of quality of power. As a result of large amount of non-linear power electronic equipments harmonic distortion is frequently encountered by the utilities in each day. The purpose of active filter is to eliminate the harmonics present in the electrical signal ensuing in sustaining the quality of the power supply in the system. DSP controlled Shunt Active Filter is used in this paper to eliminate harmonics and compensate reactive power caused by nonlinear load. Discrete Fourier Transformation is used to generate reference source current. The firing pulses for shunt active filter are generated based on a hysteresis based current controller implemented in a DSP controller, so that SAF allows elimination of the harmonics and compensation of reactive power component of load current, ensuing in a supply current which is purely sinusoidal. Simulation results of the proposed SAF to meet the requirements of IEEE-519 standards are given.

Cognitive Radio (CR) has been identified as one of the intelligent solution for Smart Grid (SG) network to transmit Giga-byte data over diverse environments and distribute the electricity to the customers. The basic principle adopted in CR based smart grid network to enhance the performance is effectively utilizing the unused spectrum. To improve the reward function a clustering based Fair Channel Allocation (FCA) algorithm among Secondary Users (SU) has been proposed in this paper. By efficiently allocating the channels among the secondary users, the user and channel rewards can be improved. Analytical equations have been developed for the performance parameters such as user reward, channel reward and Jain’s fairness index which has been simulated using MATLAB R2014b.

Future 5G wireless networks demands for higher energy efficiency and spectral efficiency. To improve the energy efficiency of the wireless networks over fading channels, RF energy harvesting technique can be employed. In this paper, Energy-assisted Amplify and Forward (EAF) cooperative relay protocol has been proposed. To minimize the energy consumption of the battery, Power-Splitting (PS) based Simultaneous Wireless Information and Power Transfer (SWIPT) technique has been adopted in the relay nodes of cooperative wireless networks. The PS technique splits the received signal from the Access Point (AP) into two streams of different power. First stream goes to the information receiver module and the next stream goes to the energy harvester module in the relay. Analytical model and equations have been developed for the performance parameters such as capacity and throughput of the EAF protocol and they have been compared with the Energy-assisted Decode and Forward (EDF) protocol using MATLAB R2013a. It is observed that the capacity and throughput of the EAF relay protocol is 8.6% and 45% better than the EDF relay protocol respectively.

Protective alumina thin films of different thicknesses (35–95 nm) were grown by pulsed RF magnetron sputtering technique at room temperature on germanium (Ge) coated black polyimide or Kapton® substrate which is often employed as sunshield membrane on communications satellite antennas. The thin alumina top layer provides shielding of Ge coating from degradation during storage. The alumina thin film was characterized by X-ray diffraction, field emission scanning electron microscopy and X-ray photoelectron spectroscopy (XPS) techniques to investigate microstructural and electronic characteristics. Thermo-optical properties such as IR emittance, solar absorptance, reflectance and transmittance and electrical property e.g. sheet resistance of the deposited alumina films were measured. The RF losses e.g. insertion loss and return loss were measured in both Ku band (10.5–14.5 GHz) and Ka band (27–40 GHz). Finally, to prove anti-degradation behavior of alumina thin film, water droplet spreading experiments were carried out and evaluated its chemical degradation by XPS.

SHS activities in India can be broadly discussed under the topics of solid-state combustion and solution combustion. In this article, the focus is on the practice of solid-state SHS activities based on the technology developed in Russia.

Future high speed mobile applications require diverse Quality of Service (QoS). To provide flexible data rate services while satisfying the low delay requirements, adaptive MIMO OFDM is a promising technique over time varying channels. In this paper a variable power adaptive MIMO OFDM system under imperfect CSI using cross layer design for mobile ad hoc networks is proposed. Data throughput is maximized while maintaining the delay QoS requirements in the presence of channel estimation errors. Numerical results show that the variable power adaptive MIMO OFDM system provides better spectral efficiency than its constant power counterpart.

Cognitive radio (CR) has become a key technology for addressing spectrum scarcity. In CR networks, spectrum access should not interfere the incumbent networks. Due to the requirement above, common control channel approaches, which are widely used in traditional multichannel environments, may face serious CR long-time blocking problem and control channel saturation problem. Although channel-hopping-based approaches can avoid these two problems, existing works still have significant drawbacks including long time-to-rendezvous, unbalance channel loading, and low channel utilization. This paper tends to the issue of range mindful survivable methodologies with disappointment likelihood limitations under static activity in adaptable transfer speed optical systems. The joint disappointment likelihood amongst essential and reinforcement ways must be beneath the most extreme fair joint disappointment likelihood for each activity request. It creates whole number direct program (ILP) models for committed way security and shared-way assurance with a specific end goal to limit the aggregate number of recurrence spaces expended, and furthermore propose a range mindful devoted insurance (SADP) calculation and a range mindful shared security (SASP) calculation. This demonstrates the ILP show arrangements devour least number of recurrence spaces, however prompt higher normal joint disappointment likelihood contrasted with the SADP and SASP calculations. In addition, both the SADP and SASP calculations accomplish a superior execution as far as aggregate number of recurrence openings expended when contrasted with a customary devoted way insurance calculation and an ordinary shared-way assurance calculation, separately, however prompt higher normal joint disappointment likelihood.

Extant literature has pointed at how process and outcome of service encounters impact the overall service evaluation. Little has been known about how individuals process these two elements (process vs. outcome) and evaluate them. We draw theoretical insights from Construal Level Theory and propose that individuals assign asymmetric weights to the two elements of service encounters based on the Construal Level associated with the context of the service experience. We test our propositions with real consumer reviews posted on an online portal and find support for the same. We provide theoretical and managerial insights.

Wireless Sensor Networks (WSN) consists of a large number of miniature size, low-power, smart sensor nodes interfacing with one another and deployed over a certain inaccessible geographical locale having inadequate power and storage space. Energy efficiency is a foremost concern in WSN. To maximize the network lifetime, one possible solution is to harvest energy from the ambient boundless accessible energy sources in the environment nearby to the sensor nodes. The use of energy harvesting (EH) nodes as cooperative relays is a promising and budding solution in WSN. Energy harvest from one source is not sufficient to congregate the power requirement of sensor nodes. In this work, in order to improve the network lifetime electromagnetic radiation energy harvesting (EMR EH) method has been proposed. Communication is carried out by signal cooperation through relays in order to assist the sources to exchange their data for longer time periods. The current slot's transmission is based on transmitter knowledge about the present channel signal to noise ratio (SNR), past harvested energy and present energy stored in the battery. In order to solve the low power problem while maximizing the lifetime of wireless sensor nodes power management schemes like water filling energy harvesting strategies is included. The network performance metrics such as the probability of successful data exchange and the network lifetime gain has been derived and simulated using MATLAB. Simulations results illustrate that proposed technique afford enhanced result compared to existing energy harvesting schemes.

Radiative cooling devices should ideally operate with a shield substrate that completely blocks solar radiation but is transparent in the “atmospheric window” (8−13 μm) region. In this paper, we introduce a new type of shield for radiative cooling applications based on the use of polyethylene foils pigmented with nanocrystalline TiO2. Homogeneous shields were prepared by spreading colloidal suspension of TiO2 (rutile ca. 60 nm) between two polyethylene sheets followed by hot pressing. Optical and structural properties of the films were investigated using X-ray diffraction, TEM, and UV/vis/NIR and FTIR spectroscopy. The shields show high IR transmittance and high solar reflectance, which are favorable characteristics for solar radiation shields in radiative cooling devices. The mechanism for obtaining improved optical properties of nanocrystalline foils (in comparison with submicrometer bulk foils) is discussed with respect to both the materials and the shield preparation method. The simplicity and low-cos...

Ontologies play an important role for the semantic web which aims at capturing domain knowledge and provide a commonly agreed understanding of a domain, which may be reused and shared across applications and groups. Developing and deploying large-scale ontology solutions typically involves several separate tasks and requires applying multiple tools. Different tools from different sources need to inter operate and are integrated into frameworks. These frameworks must be open to other commercial environments and provide connectors and interfaces to industrial standards. In this paper we propose an evaluation framework for properties of ontologies and technologies for developing and deploying ontologies.

Purpose:Doses to rectum, bladder and Point‐A in patients who received intracavitary HDR brachytherapy treatment were calculated by both orthogonal radiographsreconstruction method and by image based reconstruction method and were compared. Method and Materials: Twenty‐five patients of carcinoma cervix who received intracavitary brachytherapy treatment by micro‐Selectron HDR unit were included in this study. For these patients, in Plato treatment planning system, reconstruction of sources, applicator, organs at risk and Point‐A were done using conventional orthogonal radiographs and by using 1 mm thick CT scanimages. Bladder was identified on radiographs through a Foley's catheter inserted into it filled with 7 cc of radio‐opaque fluid and the rectum through a rectal marker. Doses were calculated at 5 points each on bladder and rectum, for the treatment dose of 7 Gy to Point‐A (right & left). On CTimages, these organs were delineated with the radiologists help and from dose‐volume‐histograms,doses to 1, 2 and 5 cc of these organs were calculated besides dose to Point‐A (right & left). Results: The critical organdoses estimated by the CT method were consistently higher when compared to those by the radiographs method. When compared to the radiographicdose maximum for bladder, doses to 1, 2 and 5 cc of bladder were higher by 89%, 69.7% and 41.6% on an average respectively. For rectum, the corresponding values were 36.6%, 21.7% and 0.4%. However dose to Point‐A did not differ by more than 3% between the two methods. Conclusion: The conventional orthogonal radiography based reconstruction method consistently underestimates the doses to critical organs while the doses to reference points are comparable in these two methods. Long‐term follow‐up in such patients can identify the threshold volumes for these critical organs beyond which complication rates are bound to rise.