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The neuropsychiatric morbidities associated with post-COVID status are important public health issues. The range and severity of morbidity varies with the type of clinical setting and time of assessment. There are limited studies on the long-term persistence of the post-COVID neuropsychiatric symptoms (PCNS). Hence, this study aims to determine the proportion of persistent PCNS after approximately 2 years of COVID and to find any risk factors for persistent PCNS.
Methods
This study was a cross-sectional study of randomly selected 2,281 individuals aged 18–60 years, currently living in the community, who were RT-PCR positive for COVID-19 from the National Institute of Mental Health and Neurosciences (NIMHANS) laboratory (at least 4 weeks before intake) from a period of 1 June 2020 to 31 March 2022. Among them, 927 individuals who met the study criteria were screened for PCNS through telephone interviews using a validated PCNS screening tool comprising sociodemographic details, life events inventory and 20 questions to assess for PCNS. 196 individuals who came positive for PCNS were further evaluated by in-person or web-based interviews with Structured Clinical Interviews for DSM–5-Research Version and World Health Organization-Post-COVID Case Report Form for persistent PCNS. Descriptive statistics, Chi2 test, Mann–Whitney U Test, and Binary logistic regression analysis were used for data analysis. The Institutional Ethics Committee approved this study.
Results
The median age of study participants was 34 years, and 51.3% were female. 68 out of 196 participants (34.7%) had persistent PCNS approximately 2 years (23.84 months) after COVID-19 infection. Chronic fatigue (10.2%), depression (6.1%), cognitive symptoms (4%), hyposmia (3.6%), hypogeusia (3.6%), anxiety (2.5%), panic disorder (2.5%) and insomnia (2%) are the main persistent symptoms. The median age of the participants with persisted PCNS (40 years) is higher compared with the median age of the participants without persisted PCNS (34 years) [Mann–Whitney U = 5,225.0, P = 0.021]. Even though significant associations were found between the development of PCNS after 4 weeks of COVID and female gender, symptomatic COVID-19, severity of COVID-19 (oxygen supplementation), hospital admission, total number of times of COVID-19, and presence of life events, this association were not found with persistence of PCNS at 2 years.
Conclusion
This study revealed that one-third of the individuals with PCNS had persistent symptoms after 2 years. Chronic fatigue is the most common persistent PCNS. Middle-aged and above age groups were found to be a risk factor for persistent PCNS.
The objective of this prospective observational study was to assess the growth and body composition of term small-for-gestational-age (SGA) infants from birth to 6 months and evaluate the effect of catch-up growth (CUG) on body composition. Term SGA newborns were recruited at birth. Anthropometry and body composition were evaluated at 3 days, 6, 10 and 14 weeks, and 6 months. Fat and fat-free mass (FM and FFM) were compared between infants with and without CUG (increase in weight Z-score by > 0·67) by air displacement plethysmography. Factors that could affect body composition and CUG, including parents’ BMI and stature, infants’ birth weight, sex and feeding, were evaluated. A total of 143 SGA newborns (sixty-six boys) with birth weight of 2336 (sd 214) g were enrolled; 109 were followed up till 6 months. Median weight Z-score increased from −2·3 at birth to −1·3 at 6 months, with 51·9 % of infants showing CUG. Infants with CUG had higher FM (1796 (sd 491) g v. 1196 (sd 474) g, P < 0·001) but similar FFM (4969 (sd 508) g v. 4870 (sd 622) g, P = 0·380), and consequently higher FM percentage (FM%) (26·5 (sd 5·8) v. 19·7 (sd 6·9), P < 0·001), compared with those without CUG. Lower birth weight, exclusive breast-feeding and higher parental stature were positively associated with CUG. In conclusion, CUG in term SGA infants in the first 6 months of life was almost entirely attributable to greater gain in FM. Follow-up of this cohort will provide insight into the long-term effect of disproportionate gain in FM in early infancy in SGA babies.
This study reports and discusses the first case of glaciotectonic landforms in the Shyok valley of the Trans-Himalayan Karakoram Range, Ladakh, where a large decomposed granite megablock (8.2 km2) along with underlying diamicton is thrust over the unconsolidated Quaternary glaciofluvial sediments along a fault gouge zone near the village of Khalsar. The absence of deformation signatures below the fault gouge indicates that the brittle fault acted as a décollement surface under frozen conditions along which the glaciotectonic megablock was translated. The other deformation features include slickensides, ductile shear, thrust propagation fold noses, clastic dykes and rafts of granite and slate within the diamicton sediments. These features indicate a subglacial glaciotectonic nappe origin of the landform. The presence of juxtaposed brittle to ductile deformation fabric, clastic dykes and the superimposition of deformed decomposed granite and diamicton over the undisturbed fluvial sediments indicates a permafrost glacial margin and proglacial environment under sufficient subglacial hydrodynamic conditions for the entrapment and transportation of the glaciotectonic megablock. The deformation fabric consistently shows a southeast orientation, indicating an advancing glacier motion from northwest to southeast. The Siachen Glacier which formerly flowed down the Nubra valley is the most likely cause of the Khalsar glaciotectonic landform.
The whitefly, Bemisia tabaci (Gennadius) is documented as a major pest on soybean. It was reported that whitefly response towards its hosts and their cultivars varies, and is mediated through various host-related factors. Considering the significance of leaf morphological characteristics in influencing the host–whitefly responses, the present investigation was conducted in screen-house conditions to study the prevailing variations in leaf morphological characteristics of soybean genotypes and their role in governing the adult whitefly attractiveness and oviposition preference. In the multiple-choice test, the whitefly population (eggs, nymphs and adults) was found to be lowest in moderately resistant genotypes (SL 1028 and SL 1074) compared to highly susceptible (DS 3105) and susceptible genotypes (SL 688, SL 958 and SL 1113). The foliar trichomes were characterized using scanning electron microscopy and leaf area, leaf lamina thickness and leaf shape data were acquired using standard procedures. To determine the factors involved in the resistance/susceptible responses towards whitefly, Pearson correlation was applied between the morphological characteristics and the whitefly population. The results show that the leaf area, trichome density, trichome length and trichome angle showed a significant positive correlation with the whitefly population, whereas leaf lamina thickness was negatively correlated. Thus, for developing whitefly-resistant germplasm, breeders should choose genotypes having narrow and thick leaves with sparse, short and flat trichomes.
In this paper, a wideband circularly polarized corrugated G-shaped grounded ring slot antenna is presented. The proposed antenna structure is excited using a coplanar waveguide-fed monopole antenna, which is placed inside a corrugated G-shaped grounded ring. Due to the asymmetry in the ground plane, two orthogonal modes, having equal magnitude and out of phase by 90° are excited, resulting in circular polarization (CP). The generation of the CP in the proposed antenna structure is explained using thin dipole current element approximation. A prototype of the proposed antenna is fabricated and tested. The measured results exhibit a 3 dB axial ratio bandwidth of 37.6% (2.22–3.25 GHz), and reflection coefficient bandwidth (|S11| ≤ −10 dB) of 47.91% (2.13–3.47 GHz). Additionally, the design guidelines are also presented for G-shaped grounded ring slot antennas.
Self-focusing of Gaussian laser beam has been investigated in quantum plasma under the effect of applied axial magnetic field. The nonlinear differential equation has been derived for studying the variations in the beam-width parameter. The effect of initial plasma electron temperature and the axial magnetic field on self-focusing and normalized intensity are studied. Our investigation reveals that normalized intensity increases to tenfolds where quantum effects are dominant. The normalized intensity further increases to twelvefolds on increasing the magnetic field.
In this paper, a compact wideband tightly-coupled dipole antenna array has been developed. Dipole elements are placed in the triangular lattice to reduce the side lobe level in the radiation pattern of one of the planes. To obtain the initial dimensions, 1-D infinite array analysis of the proposed array is carried out. The infinite array is designed to operate in 5–14.3 GHz (96.3% impedance bandwidth) frequency band. The antenna array can be used in C and X band applications. Inter-element coupling is utilized to achieve ultra-wideband performance in the proposed array. A 2 × 8 elements finite array is designed with the feed network. An ultra-wideband parallel strip to microstrip transition is used to feed the array elements. A metallic shielding for the feed network helps in reducing the back lobes. The overall size of the array with the reflector and the feed network is 148 mm × 224 mm × 54.5 mm. To validate the proposed concept, the antenna array is fabricated and tested. Impedance bandwidth of 2.8:1 along with broadside radiation pattern throughout the band of interest is observed.
In the present paper, we have investigated self-focusing of the quadruple Gaussian laser beam in underdense cold quantum plasma. The non-linearity chosen is associated with the relativistic mass effect that arises due to quiver motion of electron and electron density perturbation caused by ponderomotive force. The non-linearity modifies the plasma frequency in the dielectric function and hence the refractive index of the medium. The focusing/defocusing of the quadruple laser depends on the refractive index of the medium. We have set up non-linear differential equation that controls the beam width parameter by using well-known paraxial ray approximation and Wentzel–Krammers–Brillouin approximation. The effect of intensity parameter and electron temperature is observed on laser beam self-focusing in the presence of cold quantum plasma. From the results, it is revealed that electron temperature and the initial intensity of the laser beam control the profile dynamics of the laser beam.
The paper presents an investigation on self-focusing of cosh-Gaussian (ChG) laser beam in a relativistic–ponderomotive non-uniform plasma. It is observed numerically that the selection of decentered parameter and initial beam radius determines the focusing/defocusing of ChG laser beam. For given value of these parameters, the plasma density ramp of suitable length can avoid defocusing and enhance focusing effect significantly. Focusing length and extent of focusing may also be controlled by varying slope of the ramp density. A comparison with Gaussian beam has also been attempted for optimized set of parameters. The results establish that ChG beam focuses earlier and sharper relative to Gaussian beam. We have setup the non-linear differential equation for the beam width parameter using Wentzel–Kramers–Brillouin and paraxial ray approximation and solved it numerically using Runge–Kutta method.
The numerical simulation of non conservative system is a difficult challenge for two reasons at least. The first one is that it is not possible to derive jump relations directly from conservation principles, so that in general, if the model description is non ambiguous for smooth solutions, this is no longer the case for discontinuous solutions. From the numerical view point, this leads to the following situation: if a scheme is stable, its limit for mesh convergence will depend on its dissipative structure. This is well known since at least [1]. In this paper we are interested in the “dual” problem: given a system in non conservative form and consistent jump relations, how can we construct a numerical scheme that will, for mesh convergence, provide limit solutions that are the exact solution of the problem. In order to investigate this problem, we consider a multiphase flow model for which jump relations are known. Our scheme is an hybridation of Glimm scheme and Roe scheme.
Ultraviolet photoconductivity in Copper doped ZnO (Cu:ZnO) thin films synthesized by sol-gel technique is investigated. Response characteristics of Pure ZnO thin film and Cu:ZnO thin film UV photodetector with 1.3 at. wt % Cu doping biased at 5 V for UV radiation of λ = 365 nm and intensity = 24 µwatt/cm2 has been studied. Cu:ZnO UV photodetector is found to exhibit a high photocoductive gain (K = 1.5×104) with fast recovery (T90% = 23s) in comparison to pure ZnO thin film based photodetector (K = 4.9×101 and T90% = 41s). Cu2+ ions have been substituted in ZnO lattice which has been confirmed by X-ray diffraction (XRD) and Raman spectroscopy leading to lowering of dark current (Ioff ∼ 1.44 nA). Upon UV illumination, more electron hole pairs are generated in the photodetector due to the high porosity and roughness of the surface of the film which favours adsorption of more oxygen on the surface of the photodetector. The photogenerated holes recombined with the trapped electrons, increasing the concentration of photogenerated electrons in the conduction band enhancing the photocurrent (Ion ∼ 0.02 mA) of the Cu:ZnO photodetector.
An alternative approach is based on statistically computed signal analysis technique for the design of antenna array exhibiting lower side lobes in their radiation pattern. New and generalized expressions for the array factor of all physically realizable linear antenna arrays are introduced. An algorithm based on the statistically computed signal analysis is designed. By considering the random elements, distance between the sensors, their mean, variance, average amplitude pattern and correlation of the amplitude between the two angles, some mathematical formulations have been done and shown with the help of MATLAB. Based on these generalized expressions, a new way of synthesizing arrays with reduced side lobes is available. It applies to end fire antenna array, which may have either even or odd numbers of sensors with restricted elements spacing. Final expressions shown are a clear relationship between elements excitation and null location in the radiation patterns.
The oviposition, larval arrest and establishment by the stem borer Chilo partellus (Swinhoe) were measured on different maize genotypes during anthesis. The maize genotypes tested were: Inbred A (Susceptible), Mp 704, MBR-8637, MBR-8650, MBR-8668, Poza Rica 7832, ER-29 SVR, Katumani Composite B, MMV 400, Bulk CG 4141, and ICZ2-CM. The moths oviposited on the middle leaves of the plant and the neonate larvae moved to leaf sheaths and ear husks to feed (arrest). As they grew older, the larvae invaded the stem, ear shanks and tassel to complete feeding (establishment) and to pupate. The response of the stem borer differed with resistant and susceptible maize genotypes at anthesis. More eggs were laid and larval arrest was higher on the susceptible than on resistant genotypes. Genotypes also differed in the resistance of feeding sites to larval establishment; the genotype Poza Rica 7832 showed resistance to larval establishment in the stems and ears, but the shank was heavily infested. By contrast, MBR 8637 showed greater resistance to larval establishment in the shank than the other genotypes. These resistance sources could be utilized effectively in a maize breeding programme to develop varieties with moderate to high levels of resistance at all potential feeding sites.
The luminescent property of ZnO nanoparticles prepared using the wet chemical method has been investigated. The ZnO nanoparticles in the range 5–10 nm exhibit hexagonal Wurtzite structure, and the photoluminescence (PL) spectrum at room temperature shows a broad visible luminescence band and insignificant near-bandgap emission. The broad green luminescence is dominant at both room and boiled off liquid-nitrogen temperature, while the ultraviolet band edge emission is strongly quenched. The prepared ZnO nanoparticles have residual intermediate compound on the surface in the form of an acetate group, which acts as defect centers for the emission of green luminescence. A trace amount of zinc hydroxide is observed in one of the samples and is found to further enhance the intensity of the green luminescence. Raman scattering studies on nanoparticles indicate that the acetate/hydroxyl groups are loosely bound on the surface and are not present in the interior of the ZnO crystal structure
Size dependence of the low frequency vibrational spectra of ZnO nanocrystals prepared using chemical method has been investigated. Optical transmission spectra of the ZnO colloid solution exhibit a shift in the onset of the absorption band edge from 332 to 350 nm due to particle growth. X-ray diffraction analysis of the prepared ZnO nanocrystals exhibit peaks corresponding to the hexagonal wurtzite structure. Two peaks with unusually very high intensity were observed in the low frequency (∼ 10- 25 cm-1) Raman spectra of these nanocrystals. The peak position of these phonon modes shifted towards lower frequencies as the size of the nanocrystals increases and assigned to the confinement of acoustic phonons in ZnO nanocrystals.
The influence of the integration of ultra-thin layer of different metals (Al, Cu, Sn, Te, Pb and Au) with the c-axis oriented ZnO thin film on the ultraviolet (UV) photoresponse is investigated. The transfer of electrons from the metal layer to the semiconductor at the interface compensate the surface states which otherwise takes electrons from the interior of ZnO layer and thereby increases the conductivity under UV illumination. The Sn/ZnO sample exhibits a responsivity of the order of 8.5 KV/W at a low UV intensity of 140 μW/cm2 (⎻ = 365 nm) with a fast rise and fall time of 105 and 400 ms respectively.
In this paper we report the fabrication and characterization of Ag/(Ba,Sr)TiO3 /LaNiO3/LaAlO3 capacitors. All the films, including the top (silver) and bottom (LaNiO3) electrodes, were deposited using a pulsed laser deposition technique. The electrical and dielectric properties of (Ba,Sr)TiO3 capacitors were found to improve significantly by means of silver doping. For example, the leakage current density of a Ag/Ag-doped-(Ba,Sr)TiO3 /LaNiO3/ capacitor was about an order of magnitude lower and dielectric constant was ∼40 % higher than that of a Ag/(Ba,Sr)TiO3 /LaNiO3/capacitor over a range of biases. The improvement in the electrical properties of (Ba,Sr)TiO3 films is believed to be caused by a double role of silver. The first one is associated with the reduced oxygen vacancies due to improved oxygenation of BST films in presence of silver and the second one is associated unpinning effect of domain walls again in presence of silver.
The effects of infestation and damage by the stalk-borer, Chilo partellus (Swinhoe) (Lepidoptera: Pyralidae), were studied in the field on the grain yield of the following maize cultivare: Inbred A (susceptible), ICZ2-CM (resistant) and Katumani Composite B (a commercial early maturing cultivar). Borer infestation levels (egg-population density and larval-pupal population density) and damage levels (follar damage and stalk damage) were significantly lower during the long rainy season of 1984 than 1985. On Inbred A, oviposition by the moths during the pre-flowering and flowering stages was much more important in causing a reduction in the grain yield than that during the post-flowering stage of the crop. There was no correlation with grain yield on ICZ2-CM and Katumani. The larval-pupal population density on Inbred A (but not on ICZ2-CM or Katumani), had a significant negative correlation with grain yield. Follar damage and stalk-tunnelling by the borer only affected the grain yield of Inbred A. Under artificial infestation, the grain yield of Katumani is reduced significantly by the borer attack, but under natural infestation it escapes due to its early maturity. By comparison, ICZ2-CM has inherent resistance to C. partellus and infestation and damage by the borer have no effect on grain yield.
Two indigenous maize cuitivars, Inbred A and Nyamula, were evaluated in a field trial for their susceptibility/resistance to Chilo partellus at the artificial infestation levels of 10 larvae/plant and 20 larvae/plant. Foliar damage was caused predominantly by C. partellus, but stem-tunnelling was caused not only by C. partellus but also by another species of borer, Eldana saccharina, which invaded the crop during the tassel emergence stage and persisted during harvest. In the 10-week old crop, the number of C. partellus recorded on Nyamula was greater than on Inbred A, but the incidence of injury to foliage and stem-tunnelling on the two cuitivars was the same. At harvest the degree of damage to the two cuitivars varied. At the infestation level of 20 larvae/plant, the cuitivars suffered equal stem-tunnelling. There was a significant negative correlation between stem-tunnelling and yield for Inbred A, but the correlation was not significant for Nyamula. At the infestation level of 10 larvae/plant, the correlation between stem-tunnelling and yield was not significant for either of the cuitivars, perhaps, due to excessive activity of E. saccharina in the stalks of Inbred A.
The ovipositional responses of the stem-borer, Chilo partellus (Swinhoe), to the maize cultivar Inbred A are greater than the maize cultivar, Nyamula. These responses are elicited by certain characters of the plants that are perceivable prior to the moth's arrival on the plants (distance-perceivable) as well as those perceivable after arrival on the plants (contact-perceivable). Distance-perceivable characters were not found to be responsible for the difference in the oviposition on the two cultivars tested.
The contact-perceivable characters of the maize cultivars differ in eliciting oviposition by moths. Contact with the cultivar Nyamula elicits much less oviposition than with the other cultivar tested.