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In this paper, a high gain wideband circularly polarized (CP) microstrip antenna is presented for broadband operation. The proposed structure comprised of a partially grounded printed monopole antenna loaded with a split ring resonator and a metallic reflector. By using the metallic reflector surface underneath the patch radiator results in the reflected waves in the same phase with main lobe radiation, thereby improving the gain and it also acts like a secondary radiator to generate wideband CP behavior in the proposed design. A gain enhancement of 4.3 dBi is achieved in the operating frequency band as compared with the design without a metallic reflector. The maximum gain achieved in the presented method is 8.6 dBic over the entire operating range. The proposed design shows a wideband behavior ranging from 4.30 to 9.10 GHz with the 10-dB impedance bandwidth of 71.64%. In addition, the proposed design yielded a broadside right hand CP radiation with a 3-dB axial ratio bandwidth of 33.88% from 4.98 to 7.01 GHz. The proposed antenna is fabricated and experimental results on reflection coefficient, gain, axial ratio, and radiation patterns concede well with simulation results.
We investigate the Weibel instability (WI) in a dusty plasma which is driven to oscillation by the addition of dust grains in the plasma. Our analysis predicts the existence of three modes in a dusty plasma. There is a high-frequency electromagnetic mode, whose frequency increases with an increase in the relative number density of dust grains and which approaches instability due to the presence of dust grains. The second mode is a damping mode which exists due to dust charge fluctuations in plasma. The third mode is the oscillating WI mode. The dispersion relation and the growth rate of various modes in the dusty plasma are derived using the first-order perturbation theory. The effect of dust grain parameters on frequency and growth rate is also studied and reported.
We present a direct numerical simulation (DNS) study of pseudo-turbulence in buoyancy-driven bubbly flows for a range of Reynolds (
$150\leqslant Re\leqslant 546$
) and Atwood (
$0.04\leqslant At\leqslant 0.9$
) numbers. We study the probability distribution function of the horizontal and vertical liquid velocity fluctuations and find them to be in quantitative agreement with the experiments. The energy spectrum shows a
scaling at high
and becomes steeper on reducing
. To investigate spectral transfers in the flow, we derive the scale-by-scale energy budget equation. Our analysis shows that, for scales smaller than the bubble diameter, the net transfer because of the surface tension and the kinetic energy flux balances viscous dissipation to give
scaling of the energy spectrum for both low and high
N-methyl-D-aspartate receptor (NMDA) encephalitis is a recently described autoimmune disease that typically presents with prodromal symptoms including upper respiratory tract infection, headache, fever, nausea, vomiting and diarrhea. Psychiatric symptoms follow within weeks, including anxiety, insomnia, mania, paranoia and grandiose delusions. The diagnosis is confirmed by the detection of NMDA antibodies in the serum or cerebrospinal fluid (CSF).1 Tumours, especially teratomas, are frequently associated with NMDA encephalitis; however, only 5% of male patients older than 18 years have been found to have an underlying tumour. Optic neuropathy associated with NMDA encephalitis is being increasingly recognised in the literature2–6 and was reviewed most recently by Mugavin et al.2 in 2017. In this report, we present a case of bilateral optic neuropathy in a young man diagnosed with NMDA receptor encephalitis.
The Clinical and Translational Science Award (CTSA) Consortium and the National Center for Advancing Translational Science (NCATS) undertook a Common Metrics Initiative to improve research processes across the national CTSA Consortium. This was implemented by Tufts Clinical and Translational Science Institute at the 64 CTSA academic medical centers. Three metrics were collaboratively developed by NCATS staff, CTSA Consortium teams, and outside consultants for Institutional Review Board Review Duration, Careers in Clinical and Translational Research, and Pilot Award Publications and Subsequent Funding. The implementation program included training on the metric operational guidelines, data collection, data reporting system, and performance improvement framework. The implementation team provided small-group coaching and technical assistance. Collaborative learning sessions, driver diagrams, and change packages were used to disseminate best and promising practices. After 14 weeks, 84% of hubs had produced a value for one metric and about half had produced an initial improvement plan. Overall, hubs reported that the implementation activities facilitated their Common Metrics performance improvement process. Experiences implementing the first three metrics can inform future directions of the Common Metrics Initiative and other research groups implementing standardized metrics and performance improvement processes, potentially including other National Institutes of Health institutes and centers.
The eastern Arabian Sea is influenced by both the advection of upwelled water from the western Arabian Sea and winter convective mixing. Therefore, sediments collected from the eastern Arabian Sea can help to understand the long-term seasonal hydrographic changes. We used the planktonic foraminifera census and stable isotopic ratio (δ18O) from sediments drilled during the International Ocean Discovery Program Expedition 355 to reconstruct surface hydrographic changes in the eastern Arabian Sea during the last 350 kyr. The increased abundance of Globigerina bulloides suggests enhanced advection of upwelled water during the latter half of MIS7 and the beginning of MIS6, as a result of a strengthened summer monsoon. A large drop in upwelling and/or advection of upwelled water from the western Arabian Sea is inferred during the subsequent interval of MIS6, based on the rare presence of G. bulloides. The comparable relative abundance of Neogloboquadrina dutertrei, G. bulloides and Globigerinoides ruber suggests that during the early part of MIS5, hydrographic conditions were similar to today. The upwelling decreased and winter convection increased with the progress of the glacial interval. A good coherence between planktonic foraminiferal assemblage-based monsoon stacks from both the eastern and western Arabian Sea suggests a coeval response of the entire northern Arabian Sea to the glacial–interglacial changes. The glacial–interglacial difference in δ18Osw-ivc was at a maximum with 4–5 psu change in salinity during Termination 2 and 3, and a minimum during Termination 4. The significantly reduced regional contribution to the glacial–interglacial change in δ18Osw-ivc during Termination 4 suggests a lesser change in the monsoon.
Navigation and path analysis in a cluttered environment is a challenging task over the last few decades. In this paper, a behavior-based neural network (BNN) and reactive control architecture have been presented for navigation of the mobile robot. Two different reactive behaviors have been taken as inputs function. Obstacle position is the first reactive behavior given by u(o), whereas obstacle angle u(n) according to the target position is the second reactive behavior. The angular velocity and steering angle are the output of the controller. The backpropagation architecture reduces the errors of weight function and records the best weight data that match the BNN controller. Using the BNN algorithm, the robot reacts quickly as compared to other developed techniques. To validate the performance of the controller, simulation and experimental results have been compared in the common platforms. The deviation in results for both the scenarios is found to be within 10%. The results of the BNN algorithm have also been compared with other existing techniques. Effectiveness of the proposed technique is measured in terms of smoothness of the realistic path, collision point detection, path length, and performance time.
Opioid analgesics are often prescribed following rhinology surgery. This study aimed to evaluate whether the quantity of opioid analgesics prescribed is justified.
Patients were asked about their pain management post-operatively. Parameters recorded included: current pain (using a 10-point Likert scale); type of operation; the opioid analgesics prescribed; and the quantity of opioid tablets taken and other methods of pain relief used.
Thirty-five patients were successfully contacted. The median pain score at one week post-operation was 1 (interquartile range, 0–3). Of these 35 patients, 16 were prescribed opioids, whilst 19 were not. Patients prescribed opioids took a median of 8 tablets (interquartile range, 0.8–10.5) out of the 28 tablets prescribed.
The study shows that the quantity of post-operative opioid analgesics prescribed does not compare with the amount consumed by patients to relieve pain, resulting in a surplus of opioid medication which has the potential to be abused.
Tendencies to attend to threatening cues in the environment and to interpret ambiguous situations with negative/hostile intent maintain and may even precipitate internalizing and externalizing problems in young people with a history of maltreatment. Challenging maladaptive information-processing styles using cognitive bias modification (CBM) training may reduce symptoms.
To investigate the acceptability of CBM training in nine young people attending alternate education provision units in the UK, and 10 young people living in out-of-home care institutions in Nepal with a history of maltreatment.
CBM training consisted of five sessions of training over a 2-week period; each training session consisted of one module targeting attention biases and one module targeting interpretation biases for threat. A feedback form administered after training measured acceptability. Pre- and post-intervention measures of internalizing and externalizing symptoms were also taken.
Most young people (89%) found the training helpful and 84% found the training materials realistic. There were reductions in many symptom domains, but with individual variation. Although limited by the lack of a control condition, we established generalizability of acceptability across participants from two cultural settings.
Replication of these findings in larger feasibility randomized controlled trials with measures of attention and interpretation bias before and after intervention, are needed to assess the potential of CBM in reducing anxiety symptoms and its capacity to engage targeted mechanisms.
Growth in the immediate postnatal period for extremely low birth weight (ELBW, birth weight < 1000 g) infants is an important topic in neonatal medicine. The goal is to ensure adequate postnatal growth and to minimize complications resulting from suboptimal growth. Past efforts have focused on postnatal nutrition as well as on minimizing comorbidities. It has not been systematically assessed whether antenatal factors play a role in postnatal growth. In this report, we conducted a retrospective study on 91 maternal–neonatal pairs. We prospectively collected maternal and neonatal demographic data, neonatal nutrition in the first 7 days of life and after enteral nutrition is fully established, comorbidity data, as well as weight data from birth to 50 weeks corrected gestational age. We developed a linear mixed-effects model to examine the role of placental insufficiency, as defined by fetal Doppler studies, in postnatal weight z-score trajectory over time in the ELBW population. We relied on Akaike Information Criterion (AIC) and Bayesian Information Criterion (BIC) for model selection. Interestingly, the selected model included a quadratic term of time and a placental insufficiency-by-time interaction term. In a covariate analysis, AIC and BIC both favored a model that included calories intake in the first 7 days of life and the total duration of antibiotics as fixed-effects, but not their interaction terms with time. Overall, we demonstrated for the first time that placental insufficiency, an antenatal factor, is a major determinant of postnatal weight trajectory in the ELBW population. Prospective studies are warranted to confirm our findings.
Chickpea is one of the most important nutritious grain legume crops in the world. There is limited information available on micro- and macro-nutrients in chickpea. Therefore, an effort was made to evaluate a set of 40 chickpea genotypes belonging to all the gene pools including cultivated (Cicer arietinum) as well as wild, Cicer reticulatum from the primary gene pool, Cicer echinospermum from the secondary gene pool and Cicer microphyllum from the tertiary gene pools. Concentration in the seed of the micro- (Zn, Fe, Cu and Mn) and macro-nutrients (Ca, Mg and K) was studied. Substantial variation was observed among different gene pools for the concentration of all the nutrients. The cultivated chickpea exhibited higher seed Cu, Mn, Mg and Ca than wilds indicating positive domestication effect, whereas wild crop relatives were found to have higher levels than cultivated chickpeas for seed Zn, Fe and K concentrations. While comparing desi-type chickpeas with Kabulis, it was revealed that desi types possessed more Zn, Cu, Ca and Mg than Kabulis but reverse was true for seed Fe, Mn and K. Among different desi types (desi brown, desi green and desi black), desi brown types were generally associated with higher mineral nutrient levels. The present study led to the identification of most promising genotypes for different seed micro- and macro-nutrients. These promising lines may serve as genetic resources useful in gene discovery programmes and for alleviating malnutrition or hidden hunger in the developing world.
In this article, we investigate the chronology of a large parallel-walled mudbrick structure at the site of Pachamta in Rajasthan, India. Pachamta is larger than the contemporaneous Harappan site of Kalibangan and part of a society collectively known as the Ahar Culture. Recent excavations at Pachamta provided an opportunity to elaborate on the available dates for this society and to investigate the chronology of an enigmatic parallel-walled structure. The chronology and function of such prominent structures remains murky, although scholars have suggested that these buildings served as public storage because they resemble the granary at Harappa. Through excavation, our team collected data for assessing the Pachamta parallel-walled structure including construction methods, process of abandonment, and associated dates. The thirteen 14C assays from the site and an associated phase and sequence model performed in OxCal 4.3 demonstrate that the building was constructed, used, and abandoned in a relatively brief period. If parallel-walled structures are storage buildings, then expansion of the building may indicate prosperity or surplus, while abandonment may indicate an end to abundance or a shift in resource management. Carefully dating the structure allows us to investigate the timing of social processes including political and economic shifts within the settlement.
In this work, a new compact, low profile, frequency, and end-fire pattern reconfigurable antenna is presented. The proposed antenna consists of four parasitic elements and an electric-inductive-capacitive (ELC) resonator enclosed with a closed ring resonator (CRR). The reconfigurability in the proposed antenna is achieved with the help of five PIN diodes (D1–D5) embedded on the top surface of the substrate. The diode (D1) is implanted between ELC and CRR resonators for frequency reconfigurability. The other four diodes (D2–D5) are implanted between the ground plane and four parasitic elements to control the electrical length of the ground plane to achieve pattern diversity. The ground plane and parasitic elements steer the primary omni-directional beam to bi-directional and uni-directional end-fire radiation at multiple frequencies. The proposed antenna exhibits multiband operation and end-fire pattern diversity depending upon the different states of PIN diodes. The overall size of the proposed antenna is 0.20λ0× 0.17λ0× 0.009λ0, where λ0 is calculated at the lowest resonance frequency. The impedance bandwidth of the antenna ranges from 1.45 to 26.22%, while peak gain varies from 0.86 to 3.86 dBi depending upon the state of operation. The measured results are in agreement with the simulated results, which confirm the frequency and pattern diversity performance of the antenna. The proposed antenna can be used in back-to-back repeater systems.
A 62-year-old male presented to hospital with acute aphasia. His past medical history was significant for a previous left middle cerebral artery stroke, from which he fully recovered, hypertension, dyslipidemia, coronary artery disease, one episode of atrial fibrillation postoperatively, and thalidomide exposure in utero. Although initially he was thought to be aphasic, on further examination, he demonstrated significant abulia. His level of consciousness was normal, and neurological examination was otherwise unremarkable. A CT angiogram of the head and neck was performed. The patient was not a candidate for acute therapy, as he had established stroke on imaging, and the time of onset was unclear.
Cerebral malaria (CM) is the severe neurological complication causing acute non-traumatic encephalopathy in tropical countries. The mechanisms underlying the fatal cerebral complications are still not fully understood. Glutamate, a major excitatory neurotransmitter in the central nervous system of the mammalian brain, plays a key role in the development of neuronal cells, motor function, synaptic plasticity, learning and memory processes under normal physiological conditions. The subtypes of ionotropic glutamate receptor are N-methyl-D-aspartate receptors (NMDARs) which are involved in cellular mechanisms of learning and memory, synaptic plasticity and also mediate excitotoxic neuronal injury. In the present study, we found that glutamate level in synaptosomes, as well as expression of NMDAR, was elevated during the extreme condition of CM in C57BL6 mice. Arteether at 50 mg kg−1 × 1, 25 mg kg−1 × 2, days decreased the NMDAR expression and increased the overall survival of the experimental CM mice.
The present study investigated if the presence of encircling granulosa cells protected against di(2-ethylhexyl)phthalate (DEHP)-induced oxidative stress in rat oocytes cultured in vitro. Denuded oocytes and cumulus–oocyte complexes (COCs) were treated with or without various doses of DEHP (0.0, 25.0, 50.0, 100, 200, 400 and 800 μM) in vitro. Morphological apoptotic changes, levels of oxidative stress and reactive oxygen species (ROS), mitochondrial membrane potential, and expression levels of apoptotic markers (Bcl2, Bax, cytochrome c) were analyzed. Our results showed that DEHP induced morphological apoptotic changes in a dose-dependent manner in denuded oocytes cultured in vitro. The effective dose of DEHP (400 µg) significantly (P>0.05) increased oxidative stress by elevating ROS levels and the mitochondrial membrane potential with higher mRNA expression and protein levels of apoptotic markers (Bax, cytochrome c). Encircling granulosa cells protected oocytes from DEHP-induced morphological changes, increased oxidative stress and ROS levels, as well as increased expression of apoptotic markers. Taken together our data suggested that encircling granulosa cells protected oocytes against DEHP-induced apoptosis and that the presence of granulosa cells could act positively towards the survival of oocytes under in vitro culture conditions and may be helpful during assisted reproductive technique programmes.
There is evidence of increased morbidity, decreased quality of life, and premature mortality in people living with HIV (PLHIV) who smoke tobacco compared to PLHIV who do not smoke tobacco. Evidence-based screening for tobacco dependence, pharmacological treatment, and treatment monitoring and education into relapse prevention are not readily available in low- and middle-income countries (LMIC). We evaluated the effects of a brief tobacco dependence intervention in improving knowledge on the health effects of smoking and intention to quit smoking in PLHIV in Nepal, a low-income country in south Asia.
Using a quasi-experimental design, we assigned 59 smokers to participate in the intervention and 67 in the control group. The 1.5 h smoking cessation intervention emphasized harms of smoking, reasons for smoking and quitting, causes of relapse in previous quit attempts, and quitting strategies. We collected data at baseline and immediately post-intervention.
Findings indicate that a brief smoking cessation intervention produced a significant increase in smoking-related knowledge and intention to quit among PLHIV. The positive effects of our intervention remained significant after adjusting for potential confounders.
Our brief tobacco dependence intervention was effective in improving knowledge on the health effects of smoking and intention to quit among PLHIV. Further studies are required to evaluate the effectiveness of our intervention in increasing smoking cessation among PLHIV in LMIC.