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Background: The irrational use of antibiotics has led to the emergence of multi drug resistant pathogens. The phenomenon of MIC creeps occurs when organisms start showing raised MIC but within susceptible range giving an indication of the prevalence of rise in resistant pathogens in an area Methods: A cross sectional study in a large tertiary care hospital in North India to observe the susceptibility pattern among uropathogens and the possibility of MIC creeps. The Antimicrobial Susceptibility Testing (AST) and Minimum Inhibitory Concentration (MIC) were conducted by Vitek Compact 2. The identification of Extended Spectrum Beta Lactamase (ESBL) producers and Carbapenem Resistant Enterobacteriaceae (CRE) among Escherichia coli were noted. The MIC 50 and MIC 90 for Nitrofurantoin, the most widely used antibiotic for lower UTI, was calculated to investigate the phenomenon of MIC creep. Results: In our study, a total of 2522 urine samples were analyzed:1538 (61%) were positive with the commonest isolate being E. coli (n=736, 47.8%) followed by Klebsiella spp. (n=178, 11%). Less than 10% of resistance was observed for Fosfomycin, Amikacin, Nitrofurantoin, Imipenem, Meropenem and Colistin. ESBL producers and CRE E. coli were 528 (72% of 736) and 79 (11% of 736) respectively. Overall, 119/736 samples had an MIC ≥128. Amongst the ESBL producers, 96/528 had MIC ≥ 128 and amongst the CRE, 13/79 had MIC ≥ 128. Discussion: E. coli can be used to reflect the trends in development of resistance. In the current study, it was observed that E. coli showed a reduced susceptibility for Nitrofurantoin indicated by a creeping increase in MIC albeit within normal range. Conclusion: Trends in rising MIC should alert prescribers to use drugs such as Nitrofurantoin judiciously. Antimicrobial stewardship practices should be strongly implemented in hospitals to curb rising resistance and obtain better treatment outcomes for patients with infectious diseases.

A miniaturized four-element antenna of 20 mm × 20 mm with edge-to-edge distance of 4.9 mm between the array antennas operating from 4.6–8.6 GHz is investigated in this article. The antenna consists of 4 × integrated dipole driven elements, and complementary split ring resonator (CSRR) metacells are loaded on the both sides of each dipole arms. The loaded meta-couplers magnetically couple to dipole drivers, and the induced resonance effect improves the 10-dB impedance bandwidth (IBW) to 60.6%. To improvise the isolation between antenna elements, metallic vias are implemented that trap electromagnetic (EM)-surface waves to condense into the ground. So, the meta-couplers induce electromagnetic (EM)-propagation as surface wave trapments for radiation and decouple near-field condensed currents, acting as couplers/decouplers. The maximum isolation achieved is >−22.5 dB without any external decoupling network. The diversity parameters indicate good attributes in isotropic, indoor, and outdoor channel environments with an envelope correlation coefficient (ECC) < 0.165 and realized gain of 5.5 dBi with average radiation efficiency of 80–90% in the desired operating bands. An equivalent circuit model using lumped components is designed for the proposed four-element antenna. For validation, a prototype antenna is fabricated and measured to be implemented in 5G applications, which shows good correlation with the full-wave simulated results.

Compact, low-profile metasurface-based wideband and wide dual-band circularly polarized (CP) dielectric resonator antennas (DRAs) are presented in this paper. The rectangular-shaped DRs are loaded over two different types of strategic 7 × 7 metasurface unit cells including a "+" shape metasurface for single-band and square-slotted shape metasurface for dual-band performance. The DRs are fed diagonally with a single perturbed probe feed which is placed at an appropriate angle of 29°. Thus, the hybrid design combination of metasurface unit cells together with the angle of feed location from the center of DRs generates wideband CP radiation with enhanced 3-dB Axial Ratio (AR) and wide impedance matching bandwidths. Proposed antennas are successfully implemented and fabricated prototypes are measured demonstrating significant performance enhancement.

Energy harvesting (EH) or scavenging is recognized as harvesting energy from ambient energy sources in the surrounding environment. This paper reports a literature review on radio frequency (RF) EH using different metasurface/metamaterial structures based on split-ring resonators (SRRs), electric inductive-capacitive (ELC) resonators, square-patch unit cells, square-ring unit cells, etc. The essential parameters in rectifying antenna (rectenna) design are included, such as receiving antenna efficiency, conversion efficiency, dimensions, supporting substrate properties, frequency band, and overall performance, etc. It is noted that rectenna design using conventional antennas such as microstrip antennas, monopole antennas, slot antennas, dielectric resonator antennas, etc. suffers from low power conversion efficiency with larger size. To overcome the above-mentioned constraints and enhance the conversion efficiency with smaller size, metasurface/metamaterial structures are used as EH collectors. An introduction to EH is discussed, followed by an overview of energy sources in the ambient environment. Several hypothetical and experimental studies on metasurface-based EH systems are summarized. Published version

In this article, a low profile circularly polarized (CP) antenna with wide 3-dB axial ratio beamwidth (ARBW) is presented. Two-pair of parallel slots are etched on a circular patch and manifested as magnetic dipoles (MDs). These narrow slots are arranged symmetrically about the axes, and one pair is orthogonal to another pair of slots. The philosophy of CP radiation across a wide angular range strongly depends on the spacing between the paired-dipoles, for example spacing of $0.22\lambda _{0}$ , two-orthogonal far-field radiated components become equal across a wide-angle. Moreover, this particular spacing between the paired-dipoles provides a symmetrical electric field distribution along the periphery of the patch, which ensures the broadside LHCP radiation with wide 3-dB ARBW of 228° and 214° at the plane of $\varphi = 0^{\circ }$ and $\varphi = 90^{\circ }$ , respectively. The measured results from the fabricated prototype exhibit good agreement with the simulated results. The antenna has impedance bandwidth (IBW) and CP bandwidth (CPBW) of 2.6% (64 MHz), and 0.9% (22 MHz), respectively. The broadside radiation holds antenna gain higher than 5 dBic across the entire CPBW.

A compact metasurface-based circularly polarized (CP) dielectric resonator antenna (DRA) is proposed with wideband characteristics. The antenna forms a very simple structure, composed of a rectangular DR, a single coaxial probe, and plus-shaped unit cells-based metasurface. The metasurface is realized on a grounded FR-4 substrate. Next, a rectangular DR is loaded centrally over the metasurface. The DR is fed with a perturbed probe feed at an appropriate angle of ( θ =29°), along the diagonal line. Thus, a novel hybrid technique involving the angle of feed location from the center of DR, and the N × N unit cells-based metasurface is utilized for generating a wideband CP radiation. The resonance from the rectangular DR and surface waves along the 7× 7 plus-shaped unit cells-based metasurface is exploited to achieve a wide 3-dB axial ratio (AR) and impedance matching bandwidth. The fabricated antenna prototype used for the validation of predicted results confirms the successful implementation of the proposed technique. Measured results demonstrate a wide impedance bandwidth of 32% (3.6 GHz - 7.0 GHz) and an overlapping 3-dB AR bandwidth of 20.4% (4.2 GHz - 5.2 GHz). Moreover, the antenna adopts a left-hand circular polarization (LHCP) with 6-7 dBic measured gain within the operational frequency range. Overall, the proposed antenna offers low-profile, simplicity, ease of design, and high performance.

Vitamins are essential for various biological responses such as immune function and gene expression in humans. The infections of respiratory tract with Klebsiella pneumoniae is quite common throughout the world. Vitamin C supplements reduces the duration and symptoms of the respiratory infections shown by few therapeutic trials. This study was undertaken to find out whether Vitamin C has got any effect upon the sensitivity pattern of antibacterial prescribed for Klebsiella pneumoniae isolated from respiratory samples using disc diffusion method in vitro. In our study, by using student T test analysis, Vitamin C significantly decreased the inhibition zone of antibiotics Ciprofloxacin (40%), Imipenem (72%) indicating a decrease in their antibacterial effect invitro. Also, Vitamin C enhanced the antibacterial effect of Doxycycline (64%) and Ceftazidime-Clavulanic acid (36%) significantly. Significant decrease in zone diameter was observed on addition of Vitamin C to antibiotics, Imipenem (56%), Ciprofloxacin (40%). It is to be noted that effect of Vitamin C on Ceftazidime-Clavulanic acid is both increase and decrease in zone diameter which were also statistically significant. This might be due to small sample size of isolates (Number – 50) undertaken in the study. The observations noted in this study need further development in terms of increased number of isolates and proper standardization of Vitamin concentrations, with respect to each antibiotic. Being an invitro study, it does not establish any chemical interactions between Vitamins and antibiotics and needs further research by clinical methods. Key Messages: The interaction of Vitamin C on antibacterial against common respiratory pathogens needs further exploration in the area of research as they show interesting results when studied invitro under a small sample size. Keywords: Vitamin C, Klebsiella pneumoniae, Antibacterials.

Ludwig’s angina is a rapidly spreading, potentially fatal infection of deep fascial spaces of the neck leading to airway oedema and death. This, in recent times when associated with COVID-19 infection, possess treatment challenges making the patient susceptible to opportunistic infections with reduced healing potential. Owing to the multifactorial aetiology in our case and addressing them at the earliest, it is important to achieve favourable outcomes. The space infection that seeded with untreated trivial dental caries progressed to necrotising fasciitis of neck with mycobacterial growth on cartridge-based nucleic acid amplification test for tuberculosis testing. The presence ofMycobacteriumorganisms should be speculated in patients with pulmonary signs of tuberculosis (TB) because a suppurative TB lymphadenitis of neck could also have the same presentation. The decisive moment in successful outcome was identification of mycobacteria in COVID-19 infected patient, thereby allowing to initiate the antitubercular therapy along with surgical debridement. Thus, medical management of patient with cohabiting infections is difficult task and needs appropriate addressal.

Introduction: Dengue fever is the most important mosquito-borne viral disease, found to be endemic in tropical and subtropical countries. In recent decades, the incidence of dengue infection has increased around the world and has become a major public health concern. Materials and Methods: The prospective study was conducted during the period from July 2018 to December 2020 at Sri Muthukumaran Medical College, Hospital & Research Institute, Chennai, India. All the Serum samples were collected with clinically suspected cases of Dengue and then it was confirmed by (NS1 antigen, IgM & IgG antibody) rapid serological test kit. All the clinical details & Hematological parameters were also recorded. Result: During the study period, a total of 434 patients were suspected to have the Dengue infection. Majority of the cases were males 268 (62%) rather than Females 166 (38%). 146 (34%) samples were found to be positive for Dengue viral infection. Fever is the most common clinical presentation which was found in all the patients, followed by headache (56%), vomiting (52%), body pain (33.2%), Myalgia (32%), Joint pain (31.5%), Dry cough (29%), Nausea (22%), Abdominal pain (20%), Diarrhea (13%), Retro orbital pain (10%), Burning Micturition (8.2%), Hemoptysis (2.7%), and Rashes (0.2%). Hematological parameters such as Thrombocytopenia were 36 (24%), followed by Leucopenia 16 (11%), and raised Hematocrit 11 (7.2%). Conclusions: Study has revealed that clinical manifestation is varied considerably from fever, myalgia to life threatening situations like dengue hemorrhagic fever or dengue shock syndrome if not treated on time. Therefore, early recognition and prompt management is required to decrease the morbidity and mortality of illness. Keywords: Clinical profile, Dengue fever, Laboratory parameter.

Metasurface (MS) absorbers with polarization-insensitivity and wide-angle reception features have attracted much attention due to their unique absorption property. A polarization-insensitive broadband MS absorber structure, having wide-angle reception based on square split-ring resonators (SSRRs) and loaded with lumped resistors, is proposed in this paper. The proposed MS unit cell consists of a fixed-thickness FR4 dielectric substrate and a variable air-thickness substrate. The simulation results show that the proposed MS absorber is stable across a wide angular range for both normal and oblique incidences. Furthermore, the simulated results show that some parameters, such as unit-cell geometry and lumped resistors, can be varied to improve the performance of the MS absorber. The experimental results indicate that the proposed MS absorber can be achieved an absorption higher than 90% across the frequency range from 1.89 GHz to 6.85 GHz with a relative bandwidth of 113%, which is in agreement with simulation results. Thus, the proposed MS absorber can be more suitable in RF energy harvesting or wireless power transfer applications.

A broadband electromagnetic metasurface (MS) absorber with a wide-angle coverage is designed and discussed for energy harvesting applications. The proposed MS absorber consists of two split-ring resonators (SRR) forming an X-shaped in the middle and layout is designed on FR4 dielectric substrate. An air gap layer is separated between the dielectric substrate and a ground plane. At normal incidence, the proposed MS structure achieves a higher absorption ratio (>90%) with a 10-dB impedance bandwidth of more than 4 GHz (2.14 GHz-6.4 GHz). For oblique incidence, greater than 85% absorptivity is observed from $0^{\circ}, to 30^{\circ}$ across the frequencies range from 2.14 GHz to 6.4 GHz. Two higher absorption peaks of more than 80% at 2.4 GHz and from 5 GHz to 6.5 GHz for TEM polarization are achieved respectively at 45° and 60°. Furthermore, the absorption mechanism is numerically demonstrated in detail.

In this letter, a low-profile circularly polarized (CP) narrow-slots slotted-patch antenna for wide 3 dB axial-ratio beamwidth (ARBW) performance is presented. It consists of two pairs of narrow slots along the diagonal lines of a square patch with a single feed. These pairs of narrow slots are conceived and placed to serve as magnetic dipoles with quarter-wavelength separation, forcing the amplitude of the orthogonal electric field components to be equal across a wide angle. The 3 dB ARBW of the CP antenna is a strong function of the mutual magnetic field, which is feasible to alter with different parameters of the slot. The location, dimensions, and gap between the slots are tuned to achieve wide 3 dB ARBW. Measured results of the fabricated prototype exhibit 3 dB ARBW of 226° with ARmin of 0.52 dB and 198° with ARmin of 1.61 dB in two principal planes at $\boldsymbol{\varphi } = \text{0}^\circ $ and $\boldsymbol{\varphi } = \text{90}^\circ $ , respectively. The antenna offers impedance bandwidth of 85 MHz (2.448–2.533 GHz) and CP bandwidth (CPBW) of 23 MHz (2.474–2.497 GHz). The minimum peak gain is 3.87 dBic in the broadside direction.

A microwave metasurface (MS) absorber for ISM band applications is proposed and studied. The proposed MS structure consists of two metallic layers separated by two dielectric FR4 materials with a thickness of 1.6 mm. An air gap with a thickness of 10 mm placed between the dielectric layers. The proposed MS absorber exhibits near-unity absorption and wider absorption bandwidth at an operating frequency of 2.4 GHz under normal incidence. For oblique incidence, it shows wider absorption bandwidth and an absorption value of more than 93% for different incident angles for TEM-mode and more than 93% at for TE mode. Moreover, a numerical analysis presented to explain the physical interpretation of the absorption mechanism in detail.

Electromagnetic Compatibility (EMC) engineers should self-check the antenna’s condition and parameters, including Antenna Factor (AF) and Gain, continuously, by calibrating the antenna. Therefore, several analyses have been done to compare between SAM and SSM in EMC testing lab. Based on the analysis, the antenna to be used inside a 3 m semi-anechoic chamber need to be positioned 1.5 m above the ground plane to avoid the reflection. The Antenna Factor (AF) results show a good agreement with manufacturer data. SAM is recommended as a calibration method in the semi-anechoic chamber because the percentage error is 5% which is lower compared with SSM (18%). This is due to the site imperfection in the EMC lab. The uncertainty for the EMC lab is up to ±4 dB, compared to the calibration test site where allowed uncertainty is ±1 dB. Therefore, an absorber needs to be placed between two antennas. In addition, the phase center of the reference antenna needs to take into consideration for highly accurate AF.

A left hand circularly polarized (LHCP) circular microstrip patch antenna (CMSA), operating at 5.8 GHz dedicated short range communication (DSRC) band using metallic posts (MPs) is explored in this paper for road transport and traffic telematics (RTTT) application. Optimal tuning of the distance between each pair of MPs a 176◦ wide axial ratio (AR) beamwidth for on-board unit (OBU) antenna is achieved. The OBU antenna offers a 18.5 dB cross-polarization isolation well-above the European standard (CEN-EN12253) for RTTT application. Analysis of the OBU integrated on a car model is also done to evaluate the effect of a large electromagnetic object on the antenna performance. The OBU antenna integrated on a vehicle offers a considerably high gain of 10.4 dBic with the 3 dB AR beamwidth of 298◦ and 236◦ in E-plane and H-plane, respectively.

In this paper, the resonance characteristics of aperture type frequency selective surface (FSS) is presented. A systematic investigation is carried out to design the compact FSS. The optimized structure consists of rectangular Archimedean spiral with inter-digital capacitance. Resonance characteristics is verified in both single-layer as well as the double-layer approach by embedding FSS on one side of the dielectric substrate. The performances of the dual-layer are observed by varying air-gap between two FSS layers. The structure offers satisfactory resonance (transmission and reflection) characteristics at optimum air-gap of 7 mm between two layers with the 3 dB cutoff region over a frequency range (3.66–4.66 GHz). Finally, an array of 31 × 31 FSS elements of two layers is fabricated for experimental characterization. A close agreement between simulated and measured results is observed.

Freezing of Gait (FoG) is a paroxysmal and devitalizing symptom associated with Parkinson’s disease (PD). Episodes of FoG impedes gait and augments fall propensity, often leading to serious fall-injury. In this paper, we present a method for online detection of FoG using a wearable motion sensor. The novelty lies in utilizing the Empirical Wavelet Transform for signal denoising and incorporating the two new features to ameliorate the accuracy of the algorithm. Fundamentally, we have focused on a patient-independent model and leveraged a single ankle sensor which makes it a more feasible approach in terms of usability. Our model is evaluated on Daphnet dataset and achieved the average Sensitivity of.95 and Specificity of.70 with only a single sensor, demonstrating its immense potential.

In the paradigm of remote patient monitoring, clinical significance, robustness and repeatability of measurements are key aspects. Such measurements using sensors or wearables, implantable or proxemics devices are often termed “Digital Biomarkers” as they are surrogate markers for patient's health condition. We have invested in creating digital biomarkers platform which connects patients & physicians by enabling remote monitoring and augmenting clinical reports and physical examination data with the insights derived from continuous monitoring of these parameters. In this paper, we present a case-study using the platform and a wrist-worn wearable with inertial, pressure and PPG sensor onboard the device which are used to estimate various fitness and physiological parameters. We also present a robust step detection algorithm with better detection accuracy than the proprietary app in indoor trajectories with multiple sharp turns. Our method is also shown to resist false step detections with better resilience while performing activities other than walking, and detect short spells of indoor walking with significantly better accuracy.

this paper gives a complete description for the designing, and the development of a system which will be responsible and useful for proposing various ideas at University level. The main target for designing such a system is supposed to be the interactivity between the higher officials and the common people to propose ideas. A transparent system between that decision-makers and the stakeholder for the University can be managed with the help of such a system. The proposals can be submitted with the help of the system, online and can be put to vote by other stakeholders. The decision can be made with the help of positive vote for the idea proposed. Mubadarah (meaning "Idea" in Arabic) can be collected from various stakeholders of the system and can reach the decision-makers of the University. The system can be helpful enough for various other purposes.

Pervasive detection and quantification of tremor for Parkinson’s Disease (PD) patients, using Commercial Off-the-self (COTS) wrist-wearable device is an important problem to investigate. Parkinsonian tremor is one of the earliest and major surrogate biomarker which indicates the progress or status of the disease for patients under treatment using drugs or deep brain stimulation (DBS) therapy. However, it is a challenging issue as tremor occurs at the minor extremities like fingers in some cases such as pill-rolling symptom, the effect of the same on a wrist-worn motion sensor system is not significant enough to be captured. In this paper, we explore the possibility of using the wrist-based photoplethysmography (PPG) as a novel sensor modality in detecting tremor at rest. Our preliminary results gathered from healthy cohorts performing simulations of Parkinsonian tremor elucidates the merit of the proposed method. Also, since PPG acquisition is power-hungry, we have leveraged a conceptual method of compressive sensing to reduce the overall power requirement of the application.

In this work, a wideband phase shifter is designed with SIW loaded with an array of square complementary omega (SCO) in the ground plane. The SCOs are aligned in a manner wherein the stem is pointing in the direction of propagation, a constant phase shift of 45° over a wide range of frequencies with respect to a reference is obtained. The phase shifter is compact with an electrical length of 0.83λ g at 10 GHz and has an operating bandwidth ranging from 8 to 14 GHz ( 55%) with an accuracy of 5°, return loss > 15 dB and insertion loss < 1 dB.