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This paper presents a metamaterial-inspired, left-handed circularly polarized (LHCP), high-gain, and miniaturized antenna with a radiation efficiency of 92.8%. A properly arranged metamaterial containing a 4 × 4 array of unit cells is placed on the ground plane of the microstrip antenna to increase the antenna’s gain up to 12.8 dBi at 10.3 GHz. Both the unit cell and the antenna are designed on an FR4 substrate with a loss tangent of 0.02 and a relative permittivity of 4.4. The overall dimensions of the designed antenna are 0.88λ0 × 0.88λ0 × 0.052λ0, where λ0 is the free-space wavelength at 9.8 GHz. The simulated bandwidth of the prototype antenna is 2.8 GHz (9.9–12.7 GHz), while the measured bandwidth is 3.2 GHz (9.8–13 GHz). The maximum simulated and measured gains are 14.4 and 12.8 dBi, respectively, at frequencies of 10.4 and 10.3 GHz. Achieving such high gain in a small LHCP antenna is the novelty of our antenna design. The bandwidth of the proposed antenna lies within the upper X-band and lower Ku-band. Therefore, this antenna is suitable for applications such as weather monitoring and air traffic control systems.
This study from a South Indian tertiary care hospital found a 41% peri-rectal Carbapenem-resistant Enterobacterales colonization prevalence at intensive care unit admission, with New Delhi metallo-β-lactamase as the predominant carbapenemase. It underscores the need for contextually appropriate, cost-effective infection prevention strategies to mitigate the spread of resistant organisms in Indian healthcare settings.
This research aims to assess the prevalence, severity and underlying causes of hearing impairments.
Methods
This cross-sectional study used multistage stratified sampling to select 2148 individuals from Salyan and Surkhet, following the World Health Organization’s Ear and Hearing Survey Handbook.
Results
Among 1946 participants, 38.9 per cent had hearing impairments, including 15.9 per cent with disabling hearing loss, with severity increasing with age. Ear diseases affected 34.3 per cent, including dull or retracted tympanic membranes (18 per cent), impacted wax (8 per cent), perforated tympanic membrane (6.1 per cent), and abnormal tympanometry (23.1 per cent). The major causes were age-related hearing loss (50.5 per cent), Eustachian tube dysfunction (23 per cent), chronic suppurative otitis media (10.8 per cent), and otitis media with effusion (4.7 per cent). Higher education and immunisation were associated with reduced risk, while chronic conditions, earaches, drainage and tinnitus increased the risk.
Conclusion
The high prevalence of hearing impairment, primarily from preventable causes, underscores the importance of early screening and strengthened primary health care.
Transcatheter closure of large and complex atrial septal defect can pose challenges and complications during device placement. To improve stability, several assistive techniques have been developed.
Methods:
This retrospective study evaluated the efficacy of the device-assisted device closure technique for large secundum atrial septal defects. Patients who underwent device-assisted device closure of atrial septal defect between December 2023 and August 2024 were analysed.
Results:
Twenty patients (mean age 38.69 years) underwent device closure of large secundum atrial septal defect with device-assisted device closure technique. The mean atrial septal defect diameter was 31.9 mm. The average thick-to-thick measurement was 38.3 mm, which determined the device size. The majority (18 cases) had thin, floppy margins and two had deficient inferior rim. Successful closure was achieved in 18 patients (90%), while two patients (10%) required other methods of assistance. Based on fluoroscopic guidance, patients were divided into two groups: Group A (8 patients) used anteroposterior projection, and Group B (12 patients) used left anterior oblique-cranial view. After initial two failures with anteroposterior view, all cases were successfully closed using left anterior oblique-cranial projection. Device sizes ranged from 36 to 50 mm (median 40 mm). Cocoon devices were used for sizes up to 42 mm, and Occlunix for larger devices. No significant procedural complications occurred, although two patients had minor post-procedural events.
Conclusions:
Device-assisted device closure technique offers a promising and safe dynamic assistance approach for transcatheter closure of large and challenging atrial septal defects. The left anterior oblique-cranial view showed promising results, though without statistical significance. While results are encouraging, larger prospective studies are needed to validate its effectiveness.
Gravito–capillary waves at free surfaces are ubiquitous in several natural and industrial processes involving quiescent liquid pools bounded by cylindrical walls. These waves emanate from the relaxation of initial interface distortions, which often take the form of a cavity (depression) centred on the symmetry axis of the container. The surface waves reflect from the container walls leading to a radially inward propagating wavetrain converging (focussing) onto the symmetry axis. Under the inviscid approximation and for sufficiently shallow cavities, the relaxation is well-described by the linearised potential-flow equations. Naturally, adding viscosity to such a system introduces viscous dissipation that enervates energy and dampens the oscillations at the symmetry axis. However, for viscous liquids and deeper cavities, these equations are qualitatively inaccurate. In this study, we decompose the initial localised interface distortion into several Bessel functions and study their time evolution governing the propagation of concentric gravito–capillary waves on a free surface. This is carried out for inviscid as well as viscous liquids. For a sufficiently deep cavity, the inward focussing of waves results in large interfacial oscillations at the axis, necessitating a second-order nonlinear theory. We demonstrate that this theory effectively models the interfacial behaviour and highlights the crucial role of nonlinearity near the symmetry axis. This is rationalised via demonstration of the contribution of bound wave components to the interface displacement at the symmetry axis Contrary to expectations, the addition of slight viscosity further intensifies the oscillations at the symmetry axis although the mechanism of wavetrain generation here is quite different compared with bubble bursting where such behaviour is well known (Duchemin et al., Phys. Fluids, vol. 14, issue 9, 2002, pp. 3000–3008). This finding underscores the limitations of the potential flow model and suggests avenues for more accurate modelling of such complex free-surface flows.
A knowledge, attitudes and control practices (KAP)-based study on ticks and tick-borne diseases (TTBD) and resistance development in ticks was conducted in Dhar district of Madhya Pradesh covering 200 livestock owners using a questionnaire. Based on our scoring criteria, results indicated only 25% (19.16–31.60) respondents possessing basic knowledge of TTBDs while 75% (68.40–80.84) respondents were not aware of TBDs. Due to lack of proper awareness of TTBDs, about 1.28 times more respondents (OR 95% CI 0.42–3.86) were having heavy tick infestations in their animals. However, about 36.5% (29.82–43.58) respondents showed a favourable attitude towards the adoption of different tick control practices; consequently, their animals showed low-level infestation. Amongst various feeding systems for animals, a mixed type of feeding system was mostly adopted by 57.5% respondents followed by manger system (37.5%) while grazing was the least adopted method (5%). Results indicated that the grazing animals were 6 times (OR 95% CI 2.93–12.28) more susceptible to ticks and possessed heavy tick infestation. Resistance status of collected tick isolates of Rhipicephalus microplus and Hyalomma anatolicum was assessed and revealed that both tick species were found resistant to deltamethrin. The goals of this study were to assess some of the underlying causes of ticks and TBD in livestock in Dhar district of Madhya Pradesh state using the KAP survey and resistance characterization of ticks.
Human gut microbial species are crucial for dietary metabolism and biosynthesis of micronutrients. Digested products are utilised by the host as well as several gut bacterial species. These species are influenced by various factors such as diet, age, geographical location, and ethnicity. India is home to the largest human population in the world. It is spread across diverse ecological and geographical locations. With variable dietary habits and lifestyles, Indians have unique gut microbial composition. This review captures contrasting and common trends of gut bacterial community establishment in infants (born through different modes of delivery), and how that bacterial community manifests itself along infancy, through old age between Indian and global populations. Because dysbiosis of the gut community structure is associated with various diseases, this review also highlights the common and unique bacterial species associated with various communicable as well as noncommunicable diseases such as diarrhoea, amoebiasis, malnutrition, type 2 diabetes, obesity, colorectal cancer, inflammatory bowel disease, and gut inflammation and damage to the brain in the global and Indian population.
A new species of congrid eel genus, Ariosoma is described here based on two mature female specimens collected from trawl by-catch landings at Thoothukudi fishing harbour, off Thoothukudi, Bay of Bengal. The new species can be easily distinguished from its congeners in having pre-anal length 48.7–49.1% TL; dorsal-fin origin just before pectoral-fin insertion; body bicoloured, pale brown dorsally and silvery white ventrally; preopercular portion dark; pectoral fin reddish with dark spot at the base; SO canal with six pores; pre-dorsal vertebrae 10–11; pre-anal vertebrae 61–64; total vertebrae 162–163. Further, the new species differs from all the congeners of Indian waters in having more total vertebrae, except A. albimaculatum (162–163 vs 129–153 in others; 161–164 in A. albimaculatum). The new species identity was also supported by molecular analyses using the mitochondrial COI gene and the result revealed that the new species is closely related to Ariosoma maurostigma and Ariosoma albimaculatum with a pair-wise genetic distance of 11.4% and 11.6% followed by A. melanospilos with 16.8%.
Indigofera oblongifolia Forssk. locally known as ‘Goilia or Jhil’, is an important underutilized leguminous browse shrub for small ruminants in hot arid region of India and traditionally utilized for its medicinal value. Its irregular patchy distribution was observed in depression of rocky areas, bunds of farmer fields and along the depression on the road sides in Jaisalmer and Pali district during collection. Soil samples collected from Pali district have high level of pH and electrical conductivity as compared to Jaisalmer which indicates its suitability to saline areas. It exhibited good plant growth under Jodhpur conditions with respect to plant height (171.5 cm), number of branches (47.9) and canopy diameter (100–210 and 115–180 cm in north-south and east-west direction, respectively) after 12 months of planting in fields under protected condition. Morphological characterization showed the presence of high coefficient of variation (%) in the number of raceme per branch (27.3) followed by raceme length (22.9), pod length (21.0) and least in pod width (8.1). Phytochemical results revealed that leaves of I. oblongifolia contained considerable amounts of total phenols (31.44 mg g−1), flavonoids (29.73 mg g−1) and antioxidant capacity (6.26 FRU g−1) which make its suitability as a browse species to ruminants in rangelands. Along with these finding, its traditional knowledge and utilization are detailed in this paper as to hasten further research on its various aspects for its sustainable utilization in rangelands or in alternate land use systems in the Indian hot arid region.
Epilepsy is one of the most common neurological disorders characterized by an enduring predisposition to generate seizures, which can affect all age groups. Prevalence of overall psychiatric disorders among persons with epilepsy is significantly higher, and children and adolescents with epilepsy were found to have even higher rate of disorders ranging from 35% to 50%. Along with anxiety and depressive disorders, attention deficit hyperactivity disorder (ADHD) is also a common psychiatric disorder in children and adolescents. This study was primarily aimed to estimate the prevalence of psychiatric disorders among adolescents diagnosed with epilepsy. It also looked for any association between such disorders with various sociodemographic and epilepsy related factors.
Methods
A cross sectional study was conducted among 117 adolescents aged 11 to 18 years diagnosed with epilepsy. Patients with intellectual disability were excluded. After taking written informed consent and assent from parents and participants, relevant sociodemographic and clinical data were recorded. Prediction of having a psychiatric disorder was made using multi-informant type of Strength and Difficulties Questionnaire (SDQ), with a total score in borderline range suggestive of possible and score in abnormal range suggestive of probable psychiatric disorder. Data were analysed using Statistical Package for Social Sciences (SPSS) software version 22. Chi-square test was used to find association between categorical variables. For all statistical interpretations, p < 0.05 was considered the threshold for statistical significance
Results
Assessment with multi-informant type of SDQ has predicted that 64.1% of adolescents with epilepsy has possible (23.9%) or probable (40.2%) psychiatric disorder.
Prevalence of abnormal scores for hyperactivity subscale was 29.9%, conduct subscale was 29.1%, emotional symptoms subscale was 40.2% and peer-problem subscale was 27.4%.
88 % had high pro-social score suggestive of good social behaviors.
An abnormal or borderline total difficulty score on SDQ was significantly associated with inadequate seizure control (p = 0.029). No significant association was noted between a higher total difficulty score on SDQ with age, sex, sociodemographic status or disease related variables like age of onset, duration and type of epilepsy, monotherapy or polytherapy or family history of psychiatric illness.
Conclusion
A higher proportion of adolescents with epilepsy were identified to risk of having a psychiatric morbidity, which can possibly impair the quality of life and treatment outcome, particularly in Indian context.
Early identification of such disorders using screening tools and a multidisciplinary approach for managing them at the earliest can possibly improve the outcome, for which further research is recommended.
Availability of resistance sources among cultivated varieties helps in easy utilization as donor owing to no deleterious linkage drag. In the present investigation, 121 rice varieties were screened for their resistance against a virulent isolate of Fusarium fujikuroi (Ff-10) and genotyped using reported microsatellite markers. Among 121 varieties, only eight varieties, namely Luna Sankhi, Improved Tapaswini, Sarasa, Sadabahar, CR-311, Kshira, Wifa-10 and Binadhan-8, were found to be highly resistant (HR), seven varieties were resistant (R), 31 were moderately resistant (MR), 10 were moderately susceptible (MS), 11 were susceptible (S) and the rest 54 were highly susceptible (HS). The allele diversity of molecular markers classified the population into three clusters. The highly resistant varieties were grouped in major clusters II and III, whereas the remaining genotypes were distributed in all three clusters. Analysis of molecular variance (AMOVA) resulted in 95% of the maximum diversity within the test population and 5% diversity between populations. Population structure analysis grouped the genotypes into two sub-populations based on relatedness, where most of the resistant genotypes were grouped into one sub-population and other genotypes were distributed among sub-populations. Re-examination of reported markers' trait associations with bakanae resistance in the experimental population identified marker RM-3698 as associated with resistance accounting 8.4% explained phenotypic variation. This study shows that simple sequence repeat markers can be used to assess allelic diversity and population structure of bakanae resistance in rice varieties. The highly resistant genotypes, along with resistance markers, could be used as donors in marker-assisted bakanae improvement breeding programmes.
We develop a dynamic model of corporate investment and financing, in which shocks to the value of collateralizable assets generate variation in firms’ debt capacity. We show that the degree of similarity among firms’ financial flexibility forecasts cross-sectional variation in return correlation. We test the implications of the model with firm-level data in two empirical analyses using i) an instrumental variable approach based on shocks to the value of collateralizable corporate assets and ii) the outbreak of the COVID-19 crisis as an event study. We find that firms in the same percentile of the cross-sectional distribution of financial flexibility have 62% higher correlation in stock-return residuals than firms 50 percentiles apart.
In this article, an innovative design of a broadband circularly polarized compact planar antenna for RFID (radio frequency identification) receivers is presented. The suggested structure used the concept of slots loaded parasitic element printed underneath a coplanar waveguide-fed radiator to achieve the circularly polarized (CP) radiation and size reduction. A parasitic element loaded with F-slot and L-slot, and a window-type slotted ground plane was used to achieve resonance at 2.45 GHz with right-handed circularly polarized radiation for RFID handheld reader application. Experimental results confirmed that the designed antenna of size 16.5 × 14.8 × 1.6 mm3 attained a −10 dB impedance bandwidth of 15.8% (from 2.330 to 2.716 GHz) and 3 dB AR bandwidth of 3.43% (from 2.410 to 2.494 GHz). An axial ratio of 0.43 dB was achieved in the boresight of the antenna at the 2.45 GHz RFID band. The concept of electric field distribution on the antenna was used to elaborate the excitation of CP radiation in the antenna.
Lasers are created to study the timescale of electron motion in atoms and molecules. They also have wide applications in areas like solid state, plasma physics, nanoscience and defence technology. This book helps readers to master the large variety of physical phenomena and technological aspects involved in laser technology. Besides explaining the physical principles and common techniques of laser science and technology, it also elaborates on topics like High-harmonic Generation (HHG) and strong-field Non-sequential Double Ionization (NSDI), effects of a low energy atto-second pulse, laser spectroscopy, laser cooling and trapping, quantum optics and laser applications. Many important concepts covered include a new test system design of comprehensive characterization of non-imaging laser IR guided missiles, advanced laser and opto-electronics technologies for Low Intensity Conflict (LIC) applications and development of highly advanced laser cavity and resonator for high power chemical oxygen iodine laser at the Laser Science and Technology Centre (LASTEC).
Cardiac hypertrophy is the enlargement of cardiomyocytes in response to persistent release of catecholamine which further leads to cardiac fibrosis. Chrysin, flavonoid from honey, is well known for its multifarious properties like antioxidant, anti-inflammatory, anti-fibrotic and anti-apoptotic. To investigate the cardioprotective potential of chrysin against isoproterenol (ISO), cardiac hypertrophy and fibrosis are induced in rats. Acclimatised male albino Wistar rats were divided into seven groups (n 6): normal (carboxymethyl cellulose at 0·5 % p.o.; as vehicle), hypertrophy control (ISO 3 mg/kg, s.c.), CHY15 + H, CHY30 + H & CHY60 + H (chrysin; p.o.15, 30 and 60 mg/kg respectively + ISO at 3 mg/kg, s.c.), CHY60 (chrysin 60 mg/kg in per se) and LST + H (losartan 10 mg/kg p.o. + ISO 3 mg/kg, s.c.) were treated for 28 d. After the dosing schedule on day 29, haemodynamic parameters were recorded, after that blood and heart were excised for biochemical, histological, ultra-structural and molecular evaluations. ISO administration significantly increases heart weight:body weight ratio, pro-oxidants, inflammatory and cardiac injury markers. Further, histopathological, ultra-structural and molecular studies confirmed deteriorative changes due to ISO administration. Pre-treatment with chrysin of 60 mg/kg reversed the ISO-induced damage to myocardium and prevent cardiac hypertrophy and fibrosis through various anti-inflammatory, anti-apoptotic, antioxidant and anti-fibrotic pathways. Data demonstrated that chrysin attenuated myocardial hypertrophy and prevented fibrosis via activation of transforming growth factor-beta (TGF-β)/Smad signalling pathway.
Archaeologists have used isotope analysis (δ13C, δ15N) of the collagen of human bones, as well as knowledge of available nutrients, to infer that the diet of the ancient Maya was drawn from the resources of the Maya forest landscape. The interpretations have focused on plant carbohydrates from maize and protein dominated by white-tail deer. The δ15N values of bone collagen suggest that most of the protein requirements of the Maya could have been satisfied with a mixture of wild animal flesh and wild and cultivated plants including beans. Chaya, Cnidoscolus aconitifolius, domesticated before the Spanish conquest, has a high-protein content and the potential to have been a significant contributor to the ancient Maya diet. Chaya is easily propagated, is grown in home gardens by the Maya today, and is a significant part of the local traditional diet. Chaya's stable isotopic composition of carbon (δ13C) resembles that of other terrestrial plants, but its values for nitrogen (δ15N) are significantly higher. Consumption of chaya would result in slightly higher δ15N values in humans than expected from the consumption of terrestrial animals. Thus, chaya is situated well as a component of the complex, diverse, and varied diets of ancient Mesoamericans.
This study investigates a low-profile circularly polarized (CP) antenna using coplanar waveguide feeding. Rectangular-shaped slots and an inverted L-shaped slit are entrenched into the ground plane to enhance the impedance bandwidth of the antenna. Furthermore, the antenna is implemented with six elliptical electromagnetic band gap structures on its substrate to enhance the −10 dB return loss bandwidth and also to generate CP waves. The experimental and theoretical results closely match each other and indicate that a simple and compact design antenna with dimensions of 0.317λ0 × 0.317λ0 × 0.023λ0(λ0 is the operating wavelength at 4.74 GHz in free space) achieves 36.9% (3.91–5.68 GHz) of the −10 dB return loss bandwidth and 9.98% (4.09–4.52 GHz) of the 3-dB axial ratio bandwidth, thus making it a favorable entrant for radio altimeter and wireless avionics infra-communication systems.
A mathematical model is proposed for a revolute joint mechanism with an n-degree of freedom (DOF). The matrix approach is used for finding the relation between two consecutive links to determine desired link parameters such as position, velocity and acceleration using the forward kinematic approach. The matrix approach was confirmed for a proposed 10 DOF revolute type (R-type) human upper limb model with servo motors at each joint. Two DOFs are considered each at shoulder, elbow and wrist joint, followed by four DOF for the fingers. Two DOFs were considered for metacarpophalangeal (mcp) and one DOF each for proximal interphalangeal (pip) and distal interphalangeal (dip) joints. MATLAB script function was used to evaluate the mathematical model for determining kinematic parameters for all the proposed human upper limb model joints. The simplified method for kinematic analysis proposed in this paper will further simplify the dynamic modeling of any mechanism for determining joint torques and hence, easy to design control system for joint movements.