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This study aimed: to evaluate the association between coronavirus disease 2019 infection and olfactory and taste dysfunction in patients presenting to the out-patient department with influenza-like illness, who underwent reverse transcription polymerase chain reaction testing for coronavirus; and to determine the sensitivity, specificity, and positive and negative predictive values of olfactory and taste dysfunction and other symptoms in these patients.
Methods
Patients presenting with influenza-like illness to the study centre in September 2020 were included in the study. The symptoms of patients who tested positive for coronavirus on reverse transcription polymerase chain reaction testing were compared to those with negative test results.
Results
During the study period, 909 patients, aged 12–70 years, presented with influenza-like illness; of these, 316 (34.8 per cent) tested positive for coronavirus. Only the symptoms of olfactory and taste dysfunction were statistically more significant in patients testing positive for coronavirus than those testing negative.
Conclusion
During the pandemic, patients presenting to the out-patient department with sudden loss of sense of smell or taste may be considered as positive for coronavirus disease 2019, until proven otherwise.
Resource-intensive interventions and education are susceptible to a lack of long-term sustainability and regression to the mean. The respiratory culture nudge changed reporting to “Commensal Respiratory Flora only: No S. aureus/MRSA or P. aeruginosa.” This study demonstrated sustained reduction in broad-spectrum antibiotic duration and long-term sustainability 3 years after implementation.
Gravitational waves from coalescing neutron stars encode information about nuclear matter at extreme densities, inaccessible by laboratory experiments. The late inspiral is influenced by the presence of tides, which depend on the neutron star equation of state. Neutron star mergers are expected to often produce rapidly rotating remnant neutron stars that emit gravitational waves. These will provide clues to the extremely hot post-merger environment. This signature of nuclear matter in gravitational waves contains most information in the 2–4 kHz frequency band, which is outside of the most sensitive band of current detectors. We present the design concept and science case for a Neutron Star Extreme Matter Observatory (NEMO): a gravitational-wave interferometer optimised to study nuclear physics with merging neutron stars. The concept uses high-circulating laser power, quantum squeezing, and a detector topology specifically designed to achieve the high-frequency sensitivity necessary to probe nuclear matter using gravitational waves. Above 1 kHz, the proposed strain sensitivity is comparable to full third-generation detectors at a fraction of the cost. Such sensitivity changes expected event rates for detection of post-merger remnants from approximately one per few decades with two A+ detectors to a few per year and potentially allow for the first gravitational-wave observations of supernovae, isolated neutron stars, and other exotica.
Economic progress in India over the past three decades has not been accompanied by a commensurate improvement in the nutritional status of children, and a disproportionate burden of undernutrition is still focused on socioeconomically disadvantaged populations in the poorest regions. This study examined the nutritional status of children under 3 years of age using data from the fourth round of Indian National Family Health Survey conducted in 2015–2016. Child undernutrition was assessed in a sample of 126,431 under-3 children using the anthropometric indices of stunting, underweight and wasting (‘anthropometric failure’) across 640 districts, 5489 primary sampling units and 35 states/UTs of India. Descriptive statistics were used to examine the regional pattern of childhood undernutrition. Multilevel logistic regression models were fitted to examine the adjusted effect of social group (tribal vs non-tribal) and economic, demographic and contextual factors on the risks of stunting, underweight and wasting accounting for the hierarchical nature of the data. Interaction effects were estimated to model the joint effects of socioeconomic position (household wealth, maternal education, urban/rural residence and geographical region) and social group (tribal vs non-tribal) with the likelihood of anthropometric failure among children. The burden of childhood undernutrition was found to vary starkly across social, economic, demographic and contextual factors. Interaction effects demonstrated that tribal children from economically poorer households, with less-educated mothers, residing in rural areas and living in the Central region of India had elevated odds of anthropometric deprivation than other tribal children. The one-size-fits-all approach to tackling undernutrition in tribal children may not be efficient and could be counterproductive.
A new high time resolution observing mode for the Murchison Widefield Array (MWA) is described, enabling full polarimetric observations with up to
$30.72\,$
MHz of bandwidth and a time resolution of
${\sim}$
$0.8\,\upmu$
s. This mode makes use of a polyphase synthesis filter to ‘undo’ the polyphase analysis filter stage of the standard MWA’s Voltage Capture System observing mode. Sources of potential error in the reconstruction of the high time resolution data are identified and quantified, with the
$S/N$
loss induced by the back-to-back system not exceeding
$-0.65\,$
dB for typical noise-dominated samples. The system is further verified by observing three pulsars with known structure on microsecond timescales.
We describe system verification tests and early science results from the pulsar processor (PTUSE) developed for the newly commissioned 64-dish SARAO MeerKAT radio telescope in South Africa. MeerKAT is a high-gain (
${\sim}2.8\,\mbox{K Jy}^{-1}$
) low-system temperature (
${\sim}18\,\mbox{K at }20\,\mbox{cm}$
) radio array that currently operates at 580–1 670 MHz and can produce tied-array beams suitable for pulsar observations. This paper presents results from the MeerTime Large Survey Project and commissioning tests with PTUSE. Highlights include observations of the double pulsar
$\mbox{J}0737{-}3039\mbox{A}$
, pulse profiles from 34 millisecond pulsars (MSPs) from a single 2.5-h observation of the Globular cluster Terzan 5, the rotation measure of Ter5O, a 420-sigma giant pulse from the Large Magellanic Cloud pulsar PSR
$\mbox{J}0540{-}6919$
, and nulling identified in the slow pulsar PSR J0633–2015. One of the key design specifications for MeerKAT was absolute timing errors of less than 5 ns using their novel precise time system. Our timing of two bright MSPs confirm that MeerKAT delivers exceptional timing. PSR
$\mbox{J}2241{-}5236$
exhibits a jitter limit of
$<4\,\mbox{ns h}^{-1}$
whilst timing of PSR
$\mbox{J}1909{-}3744$
over almost 11 months yields an rms residual of 66 ns with only 4 min integrations. Our results confirm that the MeerKAT is an exceptional pulsar telescope. The array can be split into four separate sub-arrays to time over 1 000 pulsars per day and the future deployment of S-band (1 750–3 500 MHz) receivers will further enhance its capabilities.
Schizophrenia is a mental disorder characterized by social problems and disorders of thought, behaviour and cognitive functions. These impaired cognitive functions may be associated with alterations in resting state functional connectivity in schizophrenia. Therefore, the present study has been carried out to determine the resting state functional brain connectivity changes associated with schizophrenia in all the resting state networks (RSNs) using independent component analysis approach (ICA) and dual-regression based approach.
Objective
The objective of this study was to investigate the aberrant resting-state functional connectivity patterns in schizophrenia patients as compared to healthy controls.
Methods
35 schizophrenia patients and 31 healthy controls were recruited for the study and scanned by using resting state functional magnetic resonance (rsfMRI). Pre-processing and post-processing of the resting state functional data were performed using the FMRI Expert Analysis Tool (FEAT), which is a part of FSL (FMRIB's Software Library, www.fmrib. ox.ac.uk/fsl).
Results
Our results showed significantly decreased functional connectivity in the regions of left fronto-parietal network, lateral visual network, medial visual network, motor network and default mode network (DMN) in schizophrenia patients as compared with healthy controls.
Conclusion
The overall findings suggest that the alterations in these resting state network connectivity may, in part, contribute to the impairments in cognitive functions associated with schizophrenia. These findings also suggest that aberrant resting state network connectivity contributes to regional functional pathology in schizophrenia and bears significance for core symptoms.
Obsessive Compulsive Personality Disorder (OCPD) is a common, highly co-morbid disorder. Subjected to comparatively little research, OCPD shares aspects of phenomenology and neuropsychology with obsessive-compulsive spectrum disorders and neurodevelopmental disorders such as autism spectrum disorder (ASD). A greater understanding of this interrelationship would provide new insights into its diagnostic classification and generate new research and treatment heuristics.
Aims
To investigate the distribution of OCPD traits within a cohort of OCD patients. To evaluate the clinical overlap between traits of OCPD, OCD and ASD, as well as level of insight and treatment resistance.
Method
We interviewed 73 consenting patients from a treatment seeking OCD Specialist Service. We evaluated the severity of OCPD traits (Compulsive Personality Assessment Scale; CPAS), OCD symptoms (Yale–Brown Obsessive Compulsive Scale; Y-BOCS), ASD traits (Adult Autism Spectrum Quotient; AQ) and insight (Brown Assessment of Beliefs Scale; BABS).
Results
Out of 67 patients, 24 (36%) met DSM-IV criteria for OCPD, defined using the CPAS. Using Pearson's test, CPAS scores significantly (P < 0.01) correlated with total AQ and selected AQ domains but not with BABS. Borderline significant correlation was observed with Y-BOCS (P = 0.07). OCPD was not over-represented in a highly resistant OCD subgroup.
Conclusion
Disabling OCPD traits are common in the OCD clinic. They strongly associate with ASD traits, less strongly with OCD severity and do not appear related to poor insight or highly treatment-resistant OCD. The impact of OCPD on OCD treatment outcomes requires further research.
Disclosure of interest
This work did not receive funding from external sources. Over the past few years, Dr. Fineberg has received financial support in various forms from the following: Shire, Otsuka, Lundbeck, Glaxo-SmithKline, Servier, Cephalon, Astra Zeneca, Jazz pharmaceuticals, Bristol Myers Squibb, Novartis, Medical Research Council (UK), National Institute for Health Research (UK), Wellcome Foundation, European College of Neuropsychopharmacology, UK College of Mental Health Pharmacists, British Association for Psychopharmacology, International College of Obsessive-Compulsive Spectrum Disorders, International Society for Behavioural Addiction, World Health Organization, Royal College of Psychiatrists.
Dust vortices with a void at the centre are reported in this paper. The role of the spatial variation of the plasma potential in the rotation of dust particles is studied in a parallel plate glow discharge plasma. Probe measurements reveal the existence of a local potential minimum in the region of formation of the dust vortex. The minimum in the potential well attracts positively charged ions, while it repels the negatively charged dust particles. Dust rotation is caused by the interplay of the two oppositely directed ion drag and Coulomb forces. The balance between these two forces is found to play a major role in the radial confinement of the dust particles above the cathode surface. Evolution of the dust vortex is studied by increasing the discharge current from 15 to 20 mA. The local minimum of the potential profile is found to coincide with the location of the dust vortex for both values of discharge currents. Additionally, it is found that the size of the dust vortex as well as the void at the centre increases with the discharge current.
We report the observation of a nonlinear wave packet propagating through a relaxed Taylor state in the Swarthmore Spheromak eXperiment (SSX) device. The wave packet is launched by a fast, pulsed, high current (${\approx}21~\text{kA}$) single-turn theta-pinch coil mounted outside the plasma vessel. The theta-pinch coil is energized by discharging a 40 kV, 2 kJ capacitor circuit. The wave packet velocity is super-thermal and super-Alfvénic; its group velocity is more consistent with a whistler pulse than other characteristic velocities. We also observe a fast density pulse which indicates that it is not Alfvénic in nature.
The successful provision of middle-ear surgery requires appropriate anaesthesia. This may take the form of local or general anaesthesia; both methods have their advantages and disadvantages. Local anaesthesia is simple to administer and does not require the additional personnel required for general anaesthesia. In the low-resource setting, it can provide a very safe and effective means of allowing middle-ear surgery to be successfully completed. However, some middle-ear surgery is too complex to consider performing under local anaesthesia and here general anaesthesia will be required.
Conclusion
This article highlights considerations for performing middle-ear surgery in a safe manner when the available resources may be more limited than those expected in high-income settings. There are situations where local anaesthesia with sedation may prove a useful compromise of the two techniques.
A nonparaxial investigation for propagation characteristics of q-Gaussian laser beam in rippled density plasma is studied by considering the relativistic nonlinearity. The field distribution in the medium is expressed in terms of q parameter and beam width parameter f. Nonlinear parabolic partial differential equation governing the evolution of complex envelope in slowly varying approximation is solved in a modulated density profile. Analytical theory of self-focusing including higher order terms in the expansion of dielectric function up to fourth order is developed and the variation of beam width parameter f with the distance of propagation for different parameters is studied. One may note that increased value of density ripple, laser intensity and depth of modulation, increases self-focusing whereas a lower value of q shows strong self-focusing. A comparative study between paraxial and nonparaxial study has also conducted. This study is useful for research in high energy density physics.
Energy gain of electron beams in bubble regime of the laser wakefield accelerator can be optimized by improving the acceleration length, radial accelerating and focusing force, number of monoenergetic electrons trapped inside the bubble, and increasing dephasing length. In order to enlarge the dephasing length, the phase velocity of the plasma wave can be increased by optimizing the plasma density profile. We report the estimation of dephasing length using plasma density distribution with the flat and linear-upward profile using two-dimensional particle-in-cell simulations. The size of wakefield bubble depends on the plasma density. With a positive plasma density gradient, the size of bubble decreases. The front and trail part of wake bubble will have different phase velocity in plasma density gradient region. After density transition in constant density region, the bubble elongates and the velocity of the back part of the bubble increases so that the accelerated electron phase synchronizes with the phase of the plasma wave. In a result, the electron acceleration length enhances to improve the beam quality.
We have explored the thermodynamics of compressed magnetized plasmas in laboratory experiments and we call these studies ‘magnetothermodynamics’. The experiments are carried out in the Swarthmore Spheromak eXperiment device. In this device, a magnetized plasma source is located at one end and at the other end, a closed conducting can is installed. We generate parcels of magnetized plasma and observe their compression against the end wall of the conducting cylinder. The plasma parameters such as plasma density, temperature and magnetic field are measured during compression using HeNe laser interferometry, ion Doppler spectroscopy and a linear ${\dot{B}}$ probe array, respectively. To identify the instances of ion heating during compression, a PV diagram is constructed using measured density, temperature and a proxy for the volume of the magnetized plasma. Different equations of state are analysed to evaluate the adiabatic nature of the compressed plasma. A three-dimensional resistive magnetohydrodynamic code (NIMROD) is employed to simulate the twisted Taylor states and shows stagnation against the end wall of the closed conducting can. The simulation results are consistent to what we observe in our experiments.
Bovine calf scours reported to be caused by multiple aetiologies resulting in heavy mortality in unweaned calves and huge economic loss to the dairy farmers. Among these, cryptosporidiosis is an emerging waterborne zoonoses and one of the important causes of neonatal calf diarrhoea. Poor immune response coupled with primary cryptosporidial infections predispose neonatal calves to multiple secondary infections resulting in their deaths. In the present study, faecal samples from 100 diarrhoeic calves randomly picked up out of 17 outbreaks of bovine calf diarrhoea in periurban Ludhiana, Punjab in Northern India were subjected to conventional (microscopy, modified Zeihl–Neelsen (mZN) staining) and immunological and molecular techniques (faecal antigen capture ELISA and PCR) for detection of primary Cryptosporidium parvum infection as well as other frequently reported concurrent pathogens, viz. rotavirus and coronavirus, Salmonella spp., Escherichia coli, Clostridium perfringens and Eimeria spp. The faecal antigen capture ELISA and PCR revealed 35% prevalence of C. parvum in contrast to 25% by mZN staining with a relatively higher prevalence (66·7%) in younger (8–14-day-old) calves. The detection rate of the other enteropathogens associated with C. parvum was 45·71% for C. perfringens followed by Salmonella spp (40·0%), rotavirus (36·0%), coronavirus (16·0%), E. coli (12·0%) and Eimeria spp (4·0%) The sensitivity for detection of C. parvum by ELISA and mZN staining in comparison to PCR was 97·14% and 72·72%, respectively. An important finding of the study was that C. parvum alone was found in only 10% of the diarrhoeic faecal samples, whereas, majority of the samples (90%) showed mixed infections ranging from a combination of two to five agents. This is the first documentary proof of C. parvum and associated pathogens responsible for severe periurban outbreaks of bovine calf diarrhoea culminating in heavy mortality from Northern India.
The Stokes axisymmetric flow of an incompressible viscous fluid past a micropolar fluid spheroid whose shape deviates slightly from that of a sphere is studied analytically. The boundary conditions used are the vanishing of the normal velocities, the continuity of the tangential velocities, continuity of shear stresses and spin-vorticity relation at the surface of the spheroid. The hydrodynamic drag force acting on the fluid spheroid is calculated. An exact solution of the problem is obtained to the first order in the small parameter characterizing the deformation. It is observed that due to increase spin parameter value, the drag coefficient decreases. Well known results are deduced and comparisons are made with classical viscous fluid and micropolar fluid.
A s-polarized short-pulse laser impinged obliquely on an overdense plasma slab is shown to produce very significant second harmonic in the direction of specular reflection and transmission. The laser induces a non-linear current on electrons, which is curl free. However, with sharp plasma boundary, it gives rise to electromagnetic radiation at the second harmonic. Our formalism includes multiple reflections of the incident and second-harmonic waves from both the front and rear surfaces. The present work includes finiteness of the slab. The normalized second-harmonic amplitude acquires a sharp peak at some specific angle of incidence for a particular set of parameters dependent on thickness of the slab and plasma density.
In the present research work, the authors have investigated the self-focusing and defocusing of Hermite-cosh-Gaussian laser (HChG) beam in an inhomogeneous rippled density plasmas. By taking the relativistic non-linearity into account, an equation for envelope is set up and solved using Wentzel–Kramers–Brillouin and the paraxial ray approximation. An ordinary non-linear differential equation governing the beam width parameter as a function of propagation distance is set up for different mode structures of the beam. Further, a numerical study of this differential equation is carried for suitable set of plasma and laser parameters. The beam undergoes periodic self-focusing/defocusing due to relativistic non-linearity. We also report the comparison between self-focusing/defocusing of HChG beam in the absence and presence of density ripple. Presence of ripple does not only leads to substantial increase in self-focusing length, but also results in oscillatory character with decreasing f. In a relativistic case, strong oscillatory self-focusing and defocusing is observed. Further, self-focusing is enhanced with increased value of decentered parameter.