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Background and Aims: Various methods have been used to check vocal cord movements as a routine before awakening the patient at the end of thyroidectomy to rule out recurrent laryngeal nerve (RLN) palsy; out of which, fibreoptic-assisted visualisation via laryngeal mask airway (LMA) being the most desirable. Methods: Thirty patients of either sex, aged 18-65 years, American Society of Anaesthesiologists (ASA) grade I/II, scheduled for thyroidectomy under general anaesthesia (GA) were included and were randomised to receive either fibreoptic assisted (FB) or LMA CTrach-assisted (CT) visualisation of laryngeal structures at the end of thyroidectomy. The primary outcome was grade of view of laryngeal structures and secondary outcomes were time taken to achieve optimal view of laryngeal structures, ease of visualisation, hemodynamic parameters, and complications. Results: In the fibreoptic group, we obtained comparable optimal laryngeal view i.e., grade 1 and 2 in all (100%) patients in comparison to 14 (93.33%) in LMA CTrach group. The “time taken to achieve the optimal view” was significantly lower in the CTrach group when compared to Fibreoptic group (220.67 ± 95.98 vis-a-vis 136.67 ± 68.98). The ease of visualisation of laryngeal structures was comparable (P = 0.713) and the baseline haemodynamic parameters were comparable between the 2 groups and at various designated intervals. In total, 6.66% and 26.66% patients in group FB and CT group, respectively, required manoeuvres. However, difference was statistically significant (P < 0.05). Conclusion: Both Fibreoptic-assisted and LMA CTrach-assisted visualization of laryngeal structures in thyroidectomy are equally efficacious in terms of the optimal laryngeal view obtained and ease of visualisation. However, the time taken to achieve optimal laryngeal view was lesser with LMA CTrach.

In this study, the authors present three different metamaterial absorbers (MMAs) namely, T, split-I (SI) and split-Jerusalem cross (SJC) with different dimensions and geometrical configurations. The absorption rates of T-, SI- and SJC-shaped absorbers are studied at microwave frequencies. T-shaped absorber demonstrates perfect absorption at 10.19 GHz, making it suitable for single band operation, whereas SI-shaped absorber exhibits two perfect absorption peaks at 9.32 and 10.75 GHz finding its application in dual band operation. However, novel SJC-shaped absorber demonstrates multiple absorption peaks at 9.92, 10.42, 10.93, 11.75 and 13.25 GHz with absorption of 99.5, 91, 99.9, 91.8 and 99.6%, respectively, making it suitable for X- and Ku-band operations. The proposed MMAs have a thickness of around 0.8 mm (i.e.

The management of septic shock has undergone significant modifications in the past decade. Various studies have concluded that while corticosteroids reduce the duration of shock, they do not have any proven mortality benefit. Moreover, the time of initiation of corticosteroids has been debatable. Since, little literature is available on geriatric patients, we have designed a randomized trial to assess the importance of early initiation of low dose hydrocortisone comparing with the standard therapy.To determine the efficacy of early initiation of low dose hydrocortisone in reducing mortality in septic shock in geriatric patients.We conducted a single blinded, randomized controlled trial at a tertiary care hospital in India. Geriatric patients (agegt;60 years) fulfilling the criteria for septic shock were included in the study. All the participants were randomly assigned to two arms- intervention and standard therapy group. The outcomes were studied in terms of 28-day mortality, duration of ICU stay, duration of vasopressor requirement and need for mechanical ventilation.Total 120 patients were randomized to either Intervention arm (N=61) or the Standard therapy arm (N=59). The number of patients with reversal of shock was higher in the intervention arm (53.4%) but no statistically significant association (p= 0.575) was found. There was no significant difference between the two groups in terms of 28- day mortality, length of ICU stay, need for mechanical ventilation and duration of vasopressor support.This single centre trial demonstrated that there was no survival benefit associated with the early initiation of low dose hydrocortisone treatment in patients with vasopressor-dependent septic shock. It raised the concern that whether steroids are safe in elderly patients with septic shock.

Cardiovascular disease remains the leading cause of death globally and here in the United States. Diet has a major impact on the pathogenesis of atherosclerosis and subsequent cardiovascular morbidity and mortality. An unhealthy diet is the most significant potential behavioral and modifiable risk factor for ischemic heart disease. Despite these established facts, dietary interventions are far less frequent than pharmaceutical and procedural interventions in the management of cardiovascular disease. The beneficial effects of a plant-based diet on cardiovascular morbidity and mortality have been demonstrated in a number of recent clinical studies. The significant findings of each study are discussed in this review article, highlighting the role of a healthy plant-based diet in improving cardiovascular outcomes. From a clinician’s standpoint, the knowledge and understanding of the facts and data points from these recent clinical studies would ensure more effective patient counseling on the substantial benefits of dietary interventions.

Aspirin is one of the most widely used medications across the global healthcare system and is the foundation in treating ischemic heart disease, as well as secondary prevention for ischemic and valvular heart disease. Challenges arise in treating patients with cardiovascular disease who have concomitant aspirin intolerance. Through an extensive review of the literature, we provide a comprehensive background on the pharmacology of aspirin, the mechanisms behind aspirin intolerance, the importance of aspirin in cardiovascular disease, and the management of aspirin intolerance in both acute coronary syndrome and stable coronary artery disease. Our review includes a multidisciplinary approach from the internist, allergist/immunologist, and cardiologist when evaluating this important patient population.

Background: Liver abscess is common clinical condition encountered in outpatient and emergency setting however; rupture of it can lead to higher morbidity and mortality of patients. Despite different and easily accessible modalities are available to diagnose the condition early, still ruptured liver abscess presents with a common cause of acute abdomen in surgical emergency.Methods: This was a retrospective study carried in Sarojini Naidu Medical College, Agra, between 2019 and 2021. All patients with ruptured liver abscess (ultrasound diagnosed) were included in this study, and those patients having other causes of peritonitis were excluded.Results: Out of the fourty patients assessed, all patients were male (100%). The most affected age group was 31-40 years (50%) followed by 41-50 years (30%). Right hypochondrium pain was the most common presenting complaint. 80% have history of chronic alcohol intake. Twenty patients (50%) had presented with signs of toxemia. Only right lobe of the liver was affected the most in 28 patients (70%). Escherichia coli was the most common organism isolated in our study in 21patients (52.5%). A total of 16 patients (40%) had diabetes in our study and total of 7 (17.5%) patients had mortality in our study.Conclusions: Ruptured liver abscess can be diagnosed in emergency setting and is preventable if early intervention is done. It carries high morbidity and mortality so early diagnosis and prompt treatment can reduce the risk of it.

The objective of this study was to find out some specific key findings for the processing effects on the semi-solid slurry and its impact on the cast properties of the aluminum based alloys. In this focused review article, effect of semi-solid slurry on the cast composite has been discussed according to processing parameters, technological aspects and its applications. &nbsp

This research work presents novel coconut jute/ chicken egg shell (CJ/ES) bio-composite is made through using powder processing technique influenced by gelatin gel. Chicken egg shell in powder form is selected as matrix materials while coconut jute fibers act as reinforcing material is used to develop a novel processing technique. A successful incorporation of gelatin gel as a binder confirms the strong interface between egg shell and coconut jute. Developed composites are analyzed for interfacial effect by microstructural characterizations and mechanical properties.

Al6061-SS316L composite was produced by a novel reinforcement fabricated via 81 µm Al powder and micro size grind 316L stainless steel chips in semi-solid stage through liquid metallurgy. Initially powder and chip particulates were properly mixed with ball milling operation and then injected into the primary melt of AA6061 in different proportion. The effect of reinforcement incorporation has been investigated according to Reinforcement Incorporation Factor (RIF), Microstructure, Density and Micro-indentation hardness measurement. Results reveal that a successful incorporation of the reinforcements reduces the cavities of the cast composite and increase the hardness value for different replicates. RIF also affects the density and microstructure of the cast composites significantly.

This research work investigates the effect of laser shock peening (LSP) on commercially pure titanium grade 1 (CP Ti-1) weldment. The welding was done using gas tungsten arc welding (GTAW) with ERTi-2 filler wire. LSP was carried out on the cap surface of the weldment. The optical microstructure showed the Widmanstatten-type martensitic structure in the fusion zone (as-welded). The LSP fusion zone showed a refined microstructure compared to that of as-welded condition. Scanning electron microscope (SEM) of LSP weldment showed the indentation on the surface of the weld. This was a result of the surface ablation that occurred during LSP. X-ray diffraction analysis showed the absence of transformation of phases in the weldment. A reduction of 14.8% of crystalline size was observed in LSP weldment. A higher compressive residual stress was observed in LSP weldment than the as-welded condition. Tensile test showed the occurrence of failure in the base metal region in the case of LSP weldment, as against the failure in the case of as-welded condition in the fusion zone.

Fault detection and diagnosis &#x0028 FDD &#x0029 facilitates reliable operation of systems. Various approaches have been proposed for FDD like Analytical redundancy &#x0028 AR &#x0029, Principal component analysis &#x0028 PCA &#x0029, Discrete event system &#x0028 DES &#x0029 model etc., in the literature. Performance of FDD schemes greatly depends on accuracy of the sensors which measure the system parameters. Due to various reasons like faults, communication errors etc., sensors may occasionally miss or report erroneous values of some system parameters to FDD engine, resulting in measurement inconsistency of these parameters. Schemes like AR, PCA etc., have mechanisms to handle measurement inconsistency, however, they are computationally heavy. DES based FDD techniques are widely used because of computational simplicity, but they cannot handle measurement inconsistency efficiently. Existing DES based schemes do not use Measurement inconsistent &#x0028 MI &#x0029 parameters for FDD. These parameters are not permanently unmeasurable or erroneous, so ignoring them may lead to weak diagnosis. To address this issue, we propose a Measurement inconsistent discrete event system &#x0028 MIDES &#x0029 framework, which uses MI parameters for FDD at the instances they are measured by the sensors. Otherwise, when they are unmeasurable or erroneously reported, the MIDES invokes an estimator diagnoser that predicts the state&#x0028 s &#x0029 the system is expected to be in, using the subsequent parameters measured by the other sensors. The efficacy of the proposed method is illustrated using a pump-valve system. In addition, an MIDES based intrusion detection system has been developed for detection of rogue dynamic host configuration protocol &#x0028 DHCP&#x0029 server attack by mapping the attack to a fault in the DES framework.

Dual mixed slurry for AA6061/Al2O3-Al powder was formed under argon gas protection and used to fabricate composite due to the effect of free vortex flow in semi-solid stage. Initially, Al2O3 reinfo...

Invasive weeds ubiquitously found in terrestrial and aquatic ecosystems form potential feedstock for lignocellulosic ethanol production. The present study has reported a bioprocess for production of ethanol using mixed feedstock of 8 invasive weeds found in India. The feedstock was subjected to pretreatment comprising dilute acid hydrolysis (for hydrolysis of hemicellulosic fraction), alkaline delignification and enzymatic hydrolysis of cellulosic fraction. Pentose-rich and hexose-rich hydrolyzates obtained from pretreatment were fermented separately using microbial cultures of S. cerevisiae and C. shehatae. Fermentation mixture was sonicated at 35 kHz at 10% duty cycle. The time profiles of total reducing sugars, ethanol and biomass was fitted to a kinetic model using Genetic Algorithm. Sonication boosted the kinetics of fermentation 2-fold. The net bioethanol yield of the process was ∼220 g/kg raw biomass (with contributions of 86.8 and 133 g/kg raw biomass from pentose and hexose fermentations, respectively). Comparative evaluation of parameters of kinetic model under control and test conditions revealed several beneficial influences of sonication on both pentose and hexose fermentation systems such as faster transport of nutrients, substrate and products across cell membrane, rise in Monod saturation constant for substrate with concurrent reduction in substrate inhibition, and reduction of energy requirements for cell maintenance. Flow cytometry analysis of native and ultrasound-treated cells revealed no adverse influence of sonication on cell viability.

Owing to nonlinear viscoelasticity, materials often show characteristic features that resemble those of thixotropy. This issue has been debated in the literature over the past several decades, and several experimental protocols have been proposed to distinguish thixotropy from viscoelasticity. In this work, we assess these protocols by carrying out experiments using polymer solutions, thixotropic clay dispersions, and modeling their behavior, respectively, using the FENE-P constitutive equation and a viscoelastic aging model. We find that the criteria proposed in the literature, such as a step down jump in the shear rate and shear startup at different waiting times elapsed since preshear, are inadequate to distinguish thixotropy from viscoelasticity. In marked contrast, we show that the application of step-strain or step-stress after cessation of the preshear serves as a useful discriminant between thixotropy and viscoelasticity. In thixotropic materials, we observe that the application of step strain (or step stress) after cessation of the preshear eventually leads to slowing down of relaxation dynamics as a function of waiting time. However, for viscoelastic materials, the relaxation modulus (creep compliance) curve shifts to lower modulus (higher compliance) values as a function of waiting time until equilibrium is reached. While the proposed criterion offers a robust distinction between viscoelasticity and thixotropy for the systems studied here, further experimental investigations based on other systems are needed to establish its versatility and will lead to a greater insight into this long-standing issue in rheological categorization., 60 pages, 22 figures. This article may be downloaded for personal use only. Any other use requires prior permission of the author and AIP Publishing. This article appeared in (Agarwal et al., Journal of Rheology 65, 663 (2021))

Generative models have become adept at producing artifacts such as images, videos, and prose at human-like levels of proficiency. New generative techniques, such as unsupervised neural machine translation (NMT), have recently been applied to the task of generating source code, translating it from one programming language to another. The artifacts produced in this way may contain imperfections, such as compilation or logical errors. We examine the extent to which software engineers would tolerate such imperfections and explore ways to aid the detection and correction of those errors. Using a design scenario approach, we interviewed 11 software engineers to understand their reactions to the use of an NMT model in the context of application modernization, focusing on the task of translating source code from one language to another. Our three-stage scenario sparked discussions about the utility and desirability of working with an imperfect AI system, how acceptance of that system's outputs would be established, and future opportunities for generative AI in application modernization. Our study highlights how UI features such as confidence highlighting and alternate translations help software engineers work with and better understand generative NMT models., Comment: 18 pages, 1 figure. To be published in IUI 2021

We present Python Statistical Analysis of Turbulence (P-SAT), a lightweight, Python framework that can automate the process of parsing, filtering, computation of various turbulent statistics, spectra computation for steady flows. P-SAT framework is capable to work with single as well as on batch inputs. The framework quickly filters the raw velocity data using various methods like velocity correlation, signal-to-noise ratio (SNR), and acceleration thresholding method in order to de-spike the velocity signal of steady flows. It is flexible enough to provide default threshold values in methods like correlation, SNR, acceleration thresholding and also provide the end user with an option to provide a user defined value. The framework generates a .csv file at the end of the execution, which contains various turbulent parameters mentioned earlier. The P-SAT framework can handle velocity time series of steady flows as well as unsteady flows. The P-SAT framework is capable to obtain mean velocities from instantaneous velocities of unsteady flows by using Fourier-component based averaging method. Since P-SAT framework is developed using Python, it can be deployed and executed across the widely used operating systems. The GitHub link for the P-SAT framework is: https://github.com/mayank265/flume.git.

Dry sliding wear characteristics, mechanical properties and microstructural behavior of powder-chip based reinforcement silicon rich LM6 aluminum alloy, fabricated by semi-solid casting were investigated. Wear tests were conducted on powder-chip reinforced cast samples using the pin on disc apparatus under 5, 10 and 15 N with 0.4, 0.8 and 1.2 m/s sliding speeds for 250, 500 and 750 m sliding distances versus EN31 tool steel hardened to 62 HRC. An observation from the microstructure images indicated that the porosity of the cast composite reduces due to the distribution of un-melted chips inside the short cavities by the addition of reinforcement and confirmed with the obtained results of density. The fracture in cast specimens indicates that the micro-cracks were prevalently propagated along the broken eutectic silicon particles. Additionally, wear resistance was increased reasonably due to the inclusion of reinforcement under metallic wear environment. Worn surfaces SEM, EDS, XRD and, AFM analysis suggests that surfaces plastically deformed along with silicon brittle asperities which stuck on the softer surface of the contact layers, while dominant wear mechanisms were found from these surfaces and wear debris.

The MAC layer of 802.11 protocol possess inherent weakness making it vulnerable to various security attacks like denial of service, deauthentication attack, flooding attacks, rogue access point (RAP) etc. In this manuscript we focus on evil twin attack. An evil twin is a RAP setup by cloning the MAC address and the Service Set IDentifier of an existing wireless access point (AP). An evil twin is setup so that the client(s) unknowingly connect to them under the pretext that they are connected to a genuine AP. Once a client is connected, an attacker eavesdrops on its communication to hijack client’s communication, re-direct clients to malicious websites, steal credentials of the clients connecting to it. Existing methods to detect the evil twin include maintaining white lists, patching AP/client, timing based solutions, protocol modifications etc. These methods usually require extensive setup and maintenance, have scalability and compatibility issues, require changes in protocol stack making them expensive to deploy and manage. The network conditions under normal and evil twin attack are almost similar thereby crafting a signature or defining an anomaly pattern usually leads to large amount of false positives. In this manuscript, we propose an IDS for detecting the evil twin attack, which addresses most of these issues associated with the existing detection mechanisms. Further the scheme is also proved to detect a single evil twin, multiple evil twins for single AP and multiple evil twins for multiple APs. The proposed IDS has been deployed in a lab environment and its detection rate exceeds 92% mark and the accuracy is 100% in all the runs.

Tensile properties and fracture behaviors of silicon rich LM6 aluminum alloy were investigated in details for as cast alloy and modified by LM6 powdery-chip capsules. The obtained results showed that 20% modified LM6 cast composite ensured the excellent tensile properties (tensile strength of 203 MPa with 3.8% elongation). An impressive increase in the elongation (6.8%) was found for 25% modified cast composite with good ultimate tensile strength, 6.2% higher than unmodified (182 MPa). Characterization of the casts and fracture surfaces were carried out to study the effect of reinforcement particles. An influence of un-melted chip structure was observed inside the cavities and on fractured surfaces. The XRD results showed that cast consisted of inter-metallics of AlO2, Al2Si and Al4Si. It was attributed to micro-cracks prevalently propagated along the broken eutectic silicon particles and some rejected solid particles on the fractured surfaces with ductile and inter-granular fracture. Debonding and cracking of silicon particles were also detected on the fractured surface of the specimens.

A four-element MIMO (multiple-input multiple-output) antenna system utilizing planar inverted-F antenna for 5 GHz WLAN (wireless local area network, band 1: 5.15–5.35 GHz, band 2: 5.725–5.825 GHz) access point applications is presented in this paper. The detrimental effects of practical device environment on the antenna isolation performance are compensated using an array of metasurface-based isolator between the antenna elements. The proposed isolator partially absorbs the fields responsible for coupling and rotates the polarization of rest of the coupled fields. The working mechanism of the proposed isolator is explained with the surface current distribution. The proposed antenna also exhibits spatial/pattern diversity and thus, the lower values of envelope correlation coefficient make it suitable for the MIMO application.

In this paper, we present TraceHub - a platform that connects new non-trivial state-of-the-art time-series analytics with datasets from different domains. Analytics owners can run their insights on new datasets in an automated setting to find insight's potential and improve it. Dataset owners can find all possible types of non-trivial insights based on latest research. We provide a plug-n-play system as a set of Dataset, Transformer pipeline, and Analytics APIs for both kinds of users. We show a usefulness measure of generated insights across various types of analytics in the system. We believe that this platform can be used to bridge the gap between time-series analytics and datasets by significantly reducing the time to find the true potential of budding time-series research and improving on it faster.

Dhruva is a 100 MWth Research Reactor having heavy water as primary coolant and demineralized water as secondary coolant. There are three shell and tube type vertical heat exchangers in the primary coolant system. The heat exchanger is having single-pass construction on both sides, with heavy water on the tube side and demineralized light water on the shell side. Due to identifying a minor leak from tube side to shell side, one of the heat exchangers had to be taken out for repairs, which would eventually require the replacement of cover joint gaskets. The dished end covers of the heat exchanger are bolted to the shell with a double tongue and groove joint having one inner ring gasket and an outer ring gasket to provide the sealing. The gaskets used in these grooves are spiral wound metallic gasket with graphite as the filler medium. Because of the inherent design of the joint, there is a limitation in tightening torque of the flanged bolts. The inner and outer gaskets are compressed by the 60 numbers of flange bolts. The allowable torque on the bolts is limited due to the configuration. Excess tightening will result in flange rotation and induce undue stresses as well as leakage from the inner gasket. Hence to optimize the bolt loading, a stress analysis of the joint was carried out. To validate the results, a mock set-up simulating the site condition and configuration of the joint was fabricated. New gaskets were procured and tested in the mock set-up for various bolt load conditions and the results were found to be in agreement with the results of analysis. Subsequently, the heat exchanger was removed and after repair and leak rectification, the dished end covers were assembled with new gaskets as per the test results. The heat exchanger is performing satisfactorily without any leaks.

In this work, we investigate signatures of physical aging in an aqueous dispersion of Carbopol that shows yield stress and weak enhancement in elastic modulus as a function of time. We observe that the creep curves, as well as strain recovery, show a significant dependence on waiting time elapsed since shear melting. The corrected strain, which is the strain in excess of the recovered strain, has been observed to show time–waiting time superposition in the effective time domain, wherein time is normalized by time dependent relaxation time that shows a power-law dependence. The corresponding power law exponent, which is close to unity in a limit of small stresses, decreases with stress and tends to zero as stress approaches the yield stress. For a range of stresses, the material shows time–stress superposition suggesting the shape of the evolving relaxation time spectrum to be independent of the time as well as the stress. This work, therefore, suggests the presence of physical aging in an aqueous dispersion of Carbopol even though the elastic modulus shows only a weak enhancement. We also discuss the Andrade type of creep behavior in aqueous Carbopol dispersion.

An experimental setup is traditionally used to calibrate the electric (E) field probe used for the specific absorption rate (SAR) measurement of wireless communication devices. Numerical simulation is herein proposed to perform the calibration of the E-field probe. The numerical approach is validated with known calibration data at several frequencies. The unknown calibration factor at a given frequency is deduced and the corresponding SAR of the wireless communication device measured.

Wi-Fi devices have limited battery life because of which conserving battery life is imperative. The 802.11 Wi-Fi standard provides power management feature that allows stations U+0028 STAs U+0029 to enter into sleep state to preserve energy without any frame losses. After the STA wakes up, it sends a null data or PS-Poll frame to retrieve frame U+0028 s U+0029 buffered by the access point U+0028 AP U+0029, if any during its sleep period. An attacker can launch a power save denial of service U+0028 PS-DoS U+0029 attack on the sleeping STA U+0028 s U+0029 by transmitting a spoofed null data or PS-Poll frame U+0028 s U+0029 to retrieve the buffered frame U+0028 s U+0029 of the sleeping STA U+0028 s U+0029 from the AP causing frame losses for the targeted STA U+0028 s U+0029. Current approaches to prevent or detect the PS-DoS attack require encryption, change in protocol or installation of proprietary hardware. These solutions suffer from expensive setup, maintenance, scalability and deployment issues. The PS-DoS attack does not differ in semantics or statistics under normal and attack circumstances. So signature and anomaly based intrusion detection system U+0028 IDS U+0029 are unfit to detect the PS-DoS attack. In this paper we propose a timed IDS based on real time discrete event system U+0028 RTDES U+0029 for detecting PS-DoS attack. The proposed DES based IDS overcomes the drawbacks of existing systems and detects the PS-DoS attack with high accuracy and detection rate. The correctness of the RTDES based IDS is proved by experimenting all possible attack scenarios.

Commercialization of the developed technology is a prime factor for any nation and sector to retain its existence in this global economy. Day by day the technological advancement touching new high in various sectors like the automobile and aircraft industries but high design efficiency is achieved only when it is complemented by appropriate material. In the list newer addition is MMCs (Metal Matrix Composites) which are favorable because of their lower cost achieved by cheaper reinforcement, easy processing, and capabilities of mass production. In recent days, the importance of semi-solid casting has been well accepted among various processing routes for aluminum alloys despite many challenges in terms of process parameters like porosity, agglomeration, non-uniform reinforcement particle distribution, low wettability, and engulfment, and this is a main consideration for the present work. Semi-solid casting is considered to be one of the most important and effective manufacturing processes of aluminum alloy for viable mechanical and metallurgical properties in the current perspective of product requirement and competitiveness. A glimpse of the current status is presented, which shows the potential of the process which can be utilized by the industries for several benefits. In a nutshell, it can be found that process has the capability of alteration by the use of different scraps and also have flexibility according to the processing parameters like stirring, pouring temperature, type of reinforcements, etc.