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Wave-assisted propulsion (WAP) systems directly convert wave energy into thrust using elastically mounted hydrofoils. The wave conditions as well as the design of the hydrofoil drive the fluid–structure interaction of the hydrofoil and, consequently, its performance. We employ simulations using a sharp-interface immersed boundary method to examine the effect of three key parameters on the flow physics, the fluid–structure interaction as well as thrust performance of these systems – the stiffness of the torsional spring, the location of the pitch axis and the Strouhal number. We demonstrate the utility of ‘maps’ of energy exchange between the flow and the hydrofoil system, as a way to understand and predict these characteristics. The force-partitioning method (FPM) is used to decompose the pressure forces into interpretable components and to quantify the mechanisms associated with thrust generation. Based on the results from FPM, a phenomenological model for the thrust generated by the WAP foil is presented. The parameters associated with this model are estimated based on data from over 450 distinct simulations. The predictions of the model are compared with the simulations and the use of this model for guiding WAP design is discussed.
Peer victimization predicts the development of mental health symptoms in the transition to adolescence, but it is unclear whether and how parents and school environments can buffer this link.
Methods
We analyzed two-year longitudinal data from the Adolescent Brain Cognitive Development (ABCD) study, involving a diverse sample of 11 844 children across the United States (average at baseline = 9.91 years; standard deviation = 0.63; range = 8.92–11.08; complete case sample = 8385). Longitudinal associations between peer victimization and two-year changes in mental health symptoms of major depression disorder (MDD), separation anxiety (SA), prodromal psychosis (PP), and attention-deficit/hyperactivity disorder (ADHD) were examined including a wide range of covariates. Mixed linear models were used to test for the moderating effects of parental warmth and prosocial school environment.
Results
20% of children experienced peer victimization. Higher exposure to peer victimization was associated with increases in MDD, SA, and ADHD symptoms. Parental warmth was associated with decreases in MDD symptoms but did not robustly buffer the link between peer victimization and mental health symptoms. Prosocial school environment predicted decreases in PP symptoms and buffered the link between peer victimization and MDD symptoms but amplified the link between peer victimization and SA and ADHD symptoms.
Conclusions
Peer victimization is associated with increases in mental health symptoms during the transition to adolescence. Parental warmth and prosocial school environments might not be enough to counter the negative consequences of peer victimization on all mental health outcomes.
Inhibitory control develops in early childhood, and atypical development may be a measurable marker of risk for the later development of psychosis. Additionally, inhibitory control may be a target for intervention.
Methods
Behavioral performance on a developmentally appropriate Go/No-Go task including a frustration manipulation completed by children ages 3–5 years (early childhood; n = 107) was examined in relation to psychotic-like experiences (PLEs; ‘tween’; ages 9–12), internalizing symptoms, and externalizing symptoms self-reported at long-term follow-up (pre-adolescence; ages 8–11). ERP N200 amplitude for a subset of these children (n = 34) with electrophysiological data during the task was examined as an index of inhibitory control.
Results
Children with lower accuracy on No-Go trials compared to Go trials in early childhood (F(1,101) = 3.976, p = 0.049), evidenced higher PLEs at the transition to adolescence 4–9 years later, reflecting a specific deficit in inhibitory control. No association was observed with internalizing or externalizing symptoms. Decreased accuracy during the frustration manipulation predicted higher internalizing, F(2,202) = 5.618, p = 0.004, and externalizing symptoms, F(2,202) = 4.663, p = 0.010. Smaller N200 amplitudes were observed on No-Go trials for those with higher PLEs, F(1,101) = 6.075, p = 0.020; no relationship was observed for internalizing or externalizing symptoms.
Conclusions
Long-term follow-up demonstrates for the first time a specific deficit in inhibitory control behaviorally and electrophysiology, for individuals who later report more PLEs. Decreases in task performance under frustration induction indicated risk for internalizing and externalizing symptoms. These findings suggest that pathophysiological mechanisms for psychosis are relevant and discriminable in early childhood, and further, suggest an identifiable and potentially modifiable target for early intervention.
Rhino-orbito-cerebral mucormycosis is a rapidly progressive disease with high mortality rates of about 60 per cent. The increasing incidence of rhino-orbito-cerebral mucormycosis in coronavirus disease 2019 patients in India and worldwide has become a matter of concern owing to the case fatality rate. This study explored the use of low dose aspirin in decreasing the mortality rate of coronavirus disease 2019 associated mucormycosis.
Method
This was a retrospective observational study. Patients suffering from post-coronavirus disease 2019 mucormycosis were included in the study. Each patient was treated with surgical debridement and systemic amphotericin B. Low dose aspirin was added, and mortality rates were compared with the patients who did not receive aspirin.
Results
The demographic data and rhino-orbito-cerebral mucormycosis staging between the two groups were not significantly different. There was a statistically significant difference in mortality outcomes between the two groups (p = 0.029) and a 1.77 times higher risk of dying for patients not receiving aspirin. Kaplan–Meier survival indicated that patients receiving aspirin had better survival rates (p = 0.04).
The National Institute of Mental Health's Research Domain Criteria (RDoC) framework has prompted a paradigm shift from categorical psychiatric disorders to considering multiple levels of vulnerability for probabilistic risk of disorder. However, the lack of neurodevelopmentally based tools for clinical decision making has limited the real-world impact of the RDoC. Integration with developmental psychopathology principles and statistical methods actualize the clinical implementation of RDoC to inform neurodevelopmental risk. In this conceptual paper, we introduce the probabilistic mental health risk calculator as an innovation for such translation and lay out a research agenda for generating an RDoC- and developmentally informed paradigm that could be applied to predict a range of developmental psychopathologies from early childhood to young adulthood. We discuss methods that weigh the incremental utility for prediction based on intensity and burden of assessment, the addition of developmental change patterns, considerations for assessing outcomes, and integrative data approaches. Throughout, we illustrate the risk calculator approach with different neurodevelopmental pathways and phenotypes. Finally, we discuss real-world implementation of these methods for improving early identification and prevention of developmental psychopathology. We propose that mental health risk calculators can build a needed bridge between the RDoC multiple units of analysis and developmental science.
We investigate the interaction between a singular surface and a strong shock in the self-gravitating interstellar gas clouds with the assumption of spherical symmetry. Using the method of the Lie group of transformations, a particular solution of the flow variables and the cooling–heating function for an infinitely strong shock is obtained. This paper explores an application of the singular surface theory in the evolution of an acceleration wave front propagating through an unperturbed medium. We discuss the formation of an acceleration, considering the cases of compression and expansion waves. The influence of the cooling–heating function on a shock formation is explained. The results of a collision between a strong shock and an acceleration wave are discussed using the Lax evolutionary conditions.
In India, Coronavirus pandemic started in the month of march 2020 and is growing day by day. In view of India being one of the most populous countries, it is hard to follow social distancing and abide by the lockdown rules. Therefore, as of December 2020, total number of covid-19 cases has crossed the 10 million. But the recovery rate in India is high, so the fear due to Covid-19 has decreased in intensity.
Objectives
To assess level of perceived stress in isolated covid-19 patients To assess level of hopelessness in isolated covid-19 patients
Methods
30 Patients of diagnosed Covid-19 positive,who were isolated in covid care setting in Uttar Pradesh(India),above 18yrs of age,of both sexes and willing to participate in the study were included, their socio-demographic data collected. Beck’s hopelessness scale and Perceived stress scale were administered. Infection severity upto moderate was selected and ICU patients were excluded. Results were analysed using SPSS software.
Results
It was observed that level of hopelessness increased with increasing age and increasing severity of covid-19.Level of perceived stress also increased with increasing age and increasing covid severity. There was no relation seen between hopelessness level and perceived stress level and no difference was seen in the levels of hopelessness and perceived stress between the two sexes.
Conclusions
Levels of hopelessness and stress increased with increasing age and increasing severity of covid-19.No relation seen between hopelessness level and perceived stress level and no difference was seen in the levels of hopelessness and perceived stress between the two sexes.
To evaluate the utility of pre-operative transtympanic electrically evoked auditory brainstem responses and post-operative neural response telemetry in auditory neuropathy spectrum disorder patients.
Methods
Four auditory neuropathy spectrum disorder patients who had undergone cochlear implantation and used it for more than one year were studied. All four patients underwent pre-operative transtympanic electrically evoked auditory brainstem response testing, intra-operative and post-operative (at 3, 6 and 12 months after switch-on) neural response telemetry, and out-patient cochlear implant electrically evoked auditory brainstem response testing (at 12 months).
Results
Patients with better waveforms on transtympanic electrically evoked auditory brainstem response testing showed superior performance after one year of implant use. Neural response telemetry and electrically evoked auditory brainstem response measures improved in all patients.
Conclusion
Inferences related to cochlear implantation outcomes can be based on the waveform of transtympanic electrically evoked auditory brainstem responses. Robust transtympanic electrically evoked auditory brainstem responses suggest better performance. Improvements in electrically evoked auditory brainstem responses and neural response telemetry over time indicate that electrical stimulation is favourable in auditory neuropathy spectrum disorder patients. These measures provide an objective way to monitor changes and progress in auditory pathways following cochlear implantation.
Adaptive control of flow separation based on online dynamic mode decomposition (DMD) is formulated and implemented on a canonical separated laminar boundary layer via a pulse-modulated zero-net mass-flux jet actuator located just upstream of separation. Using a linear array of thirteen flush-mounted microphones, dynamical characteristics of the separated flow subjected to forcing are extracted by online DMD. This method provides updates of the modal characteristics of the separated flow while forcing is applied at a rate commensurate with the characteristic time scales of the flow. In particular, online DMD provides a time-varying linear estimate of the nonlinear evolution of the controlled flow without any prior knowledge. Using this adaptive model, feedback control is then implemented in which the linear quadratic regulator gains are computed recursively. This physics-based, autonomous approach results in more efficient flow reattachment compared with commensurate open-loop control. Four Reynolds numbers are tested to assess robustness, $Re_c = 0.9\times 10^5$, $Re_c = 1\times 10^5$, $Re_c = 1.1\times 10^5$ and $Re_c = 1.25\times 10^5$. All controlled cases exhibit a significant reduction in mean separation bubble height, requiring approximately 10 characteristic time periods to establish control.
To assess psychiatric comorbidity in patients of alcohol dependence.
Method
All the patients of alcohol dependence attending alcohol and drug de-addiction OPD and adult psychiatry OPD on specific days were screened. Those fulfilling the selection criteria were included in the study. A detailed evaluation was done for socio-demographic variables and history of drug using semi-structured proforma especially prepared for the study. Diagnosis of alcohol dependence was made according to DSM-IV-TR criteria. The patients were seen for co-morbid psychiatric illness by applying Structured Clinical Interview for DSM-IV-TR I & II (SCID I & II).
Results
Out of 37 patients 24 (64.8%) were found to have comorbid psychiatric illness. Axis I and Axis II comorbidity was found in 64.8% and 5.4% of the samples, respectively. Patients of cluster A & B personality were equally distributed in the sample. Patients with more than one comorbidity accounted for 37.8% of the sample.
Conclusion
Psychiatric comorbidity in alcohol dependence is very high, other substance in particular. Number of comorbid diagnoses in a person may as high as three.
There are major health care implications of quality of life (QOL) in longstanding disorders such as Bipolar affective disorder (BD) for the patients and their caregivers.
Objectives
The aim of the present study is to compare quality of life among bipolar disorder patients, their caregivers and to assess whether the level of depression correlates with the scores of quality of life in Bipolar Disorder patients.
Method
We compared bipolar disorder (N = 40), their caregivers (N = 40) and no psychiatric illnesses (N = 150) on health related quality of life (HRQOL) which was assessed using the 26-item World Health Organization QOL instrument (WHOQOL-BREF Hindi version). All patients were diagnosed using the Structured Clinical Interview for DSM IV. Within the group with bipolar disorder, we examined the relationship between HRQOL using WHOQOL BREF Hindi version and depression assessed using the 17-item Hamilton Depression Rating Scale (HDRS).
Results
Patients in bipolar disorder group had lower QOL on all the four domains compared to healthy controls, caregivers. The four domains of the WHOQOL scale correlated negatively with the HDRS.
Conclusions
Our findings suggest that bipolar depression and residual symptoms of depression are negatively correlated with QOL in BD patients.
Consistent with pathophysiological models of psychosis, temporal disturbances in schizophrenia spectrum populations may reflect abnormal cortical (e.g. prefrontal cortex) and subcortical (e.g. striatum) cerebellar connectivity. However, few studies have examined associations between cerebellar connectivity and timing dysfunction in psychosis populations, and none have been conducted in youth at clinical high-risk (CHR) for psychosis. Thus, it is currently unknown if impairments in temporal processes are present in CHR youth or how they may be associated with cerebellar connectivity and worsening of symptoms.
Methods
A total of 108 (56 CHR/52 controls) youth were administered an auditory temporal bisection task along with a resting state imaging scan to examine cerebellar resting state connectivity. Positive and negative symptoms at baseline and 12 months later were also quantified.
Results
Controlling for alcohol and cannabis use, CHR youth exhibited poorer temporal accuracy compared to controls, and temporal accuracy deficits were associated with abnormal connectivity between the bilateral anterior cerebellum and a right caudate/nucleus accumbens striatal cluster. Poor temporal accuracy accounted for 11% of the variance in worsening of negative symptoms over 12 months.
Conclusions
Behavioral findings suggest CHR youth perceive durations of auditory tones as shortened compared to objective time, which may indicate a slower internal clock. Poorer temporal accuracy in CHR youth was associated with abnormalities in brain regions involved in an important cerebellar network implicated in prominent pathophysiological models of psychosis. Lastly, temporal accuracy was associated with worsening of negative symptoms across 12 months, suggesting temporal dysfunction may be sensitive to illness progression.
Despite the clinical impact of motor symptoms such as agitation or retardation on the course of depression, these symptoms are poorly understood. Novel developments in the field of instrumentation and mobile devices allow for dimensional and continuous recording of motor behavior in various settings, particularly outside the laboratory. Likewise, the use of novel assessments enables to combine multimodal neuroimaging with behavioral measures in order to investigate the neural correlates of motor dysfunction in depression. The research domain criteria (RDoC) framework will soon include a motor domain that will provide a framework for studying motor dysfunction in mood disorders. In addition, new studies within this framework will allow investigators to study motor symptoms across different stages of depression as well as other psychiatric diagnoses. Finally, the introduction of the RDoC motor domain will help test how motor symptoms integrate with the original five RDoC domains (negative valence, positive valence, cognitive, social processes, and arousal/regulation).
When sober, problematic drinkers display exaggerated reactivity to threats that are uncertain (U-threat). Since this aversive affective state can be alleviated via acute alcohol intoxication, it has been posited that individuals who exhibit heightened reactivity to U-threat at baseline are motivated to use alcohol as a means of avoidance-based coping, setting the stage for excessive drinking. To date, however, no study has attempted to characterize the dispositional nature of exaggerated reactivity to U-threat and test whether it is a vulnerability factor or exclusively a disease marker of problematic alcohol use.
Method
The current investigation utilized a family study design to address these gaps by examining whether (1) reactivity to U-threat is associated with risk for problematic alcohol use, defined by family history of alcohol use disorder (AUD) and (2) reactivity to U-threat is correlated amongst adult biological siblings. A total of 157 families, and 458 individuals, participated in the study and two biological siblings completed a threat-of-shock task designed to probe reactivity to U-threat and predictable threat (P-threat). Startle potentiation was collected as an index of aversive responding.
Results
Within biological siblings, startle potentiation to U-threat [intraclass correlation (ICC) = 0.35] and P-threat (ICC = 0.63) was significantly correlated. In addition, independent of an individuals’ own AUD status, startle potentiation to U-threat, but not P-threat, was positively associated with risk for AUD (i.e. AUD family history).
Conclusion
This suggests that heightened reactivity to U-threat may be a familial vulnerability factor for problematic drinking and a novel prevention target for AUD.
Crimean-Congo haemorrhagic fever (CCHF) is an emerging zoonotic disease in India which is prevalent in neighbouring countries. CCHF virus (CCHFV) is a widespread tick-borne virus which is endemic in Africa, Asia, Eastern Europe and the Middle East. In the present study, samples of clinically suspected human cases from different areas of northern-western India were tested for the presence of CCHFV by RT–PCR through amplification of nucleocapsid (N) gene of CCHFV. Positive samples were sequenced to reveal the prevailing CCHFV genotype(s) and phylogenetic relatedness. A phylogenetic tree revealed the emergence of diverse strains in the study region showing maximum identity with the Pakistan, Afghanistan and Iran strains, which was different from earlier reported Indian strains. Our findings reveal for the first time the emergence of the Asia 1 group in India; while earlier reported CCHFV strains belong to the Asia 2 group.
This paper elaborates the effect of unmatched stored energy in high-voltage high-energy pulsed power systems. High-voltage insulation failure of KALI system is analyzed thoroughly for its occurrence. According to the simulations and analysis energy mismatch of MARX generator and Blumlein transmission line is found to be the most significant cause for high-voltage failure of the system. MARX generator and Blumlein of KALI are redesigned to attain better energy balance at same voltage level. Observations, simulation and analytical results are illustrated in the following sections.
Independent outbreaks of dengue virus (DENV) infection and sporadic cases of chikungunya virus (CHIKV) have been recorded in the metropolitan city of Delhi on several occasions in the past. However, during a recent 2010 arboviral outbreak in Delhi many cases turned negative for DENV. This prompted us to use duplex reverse transcriptase–polymerase chain reaction (D-RT–PCR) to establish the aetiology of dengue/chikungunya through sequencing of CprM and E1 genes of dengue and chikungunya viruses. Interestingly, for the first time, both DENV and CHIKV co-circulated simultaneously and in equally dominant proportion during the post-monsoon period of 2010. DENV-1 genotype III and the East Central South African genotype of CHIKV were associated with post-monsoon spread of these viruses.
A genomic library of Entamoeba histolytica (pathogenic strain HM-1: IMSS) was screened to detect repetitive DNA clones other than those from the highly abundant ribosomal DNA (rDNA). One such clone (HMc) had a 2·3 kb insert which hybridized with the main genome and not the rDNA circle. Southern hybridization of E. histolytica genomic DNA, digested with EcoR I and probed with HMc, showed multiple bands. The banding pattern was identical in all axenic pathogenic strains tested. Differences, however, existed when the banding pattern of a pathogenic strain was compared with that of a non-pathogenic strain. HMc was present in about 25–30 copies per genome in strain HM-1: IMSS. Nucleotide sequence analysis of HMc revealed a partial open reading frame which hybridized with a 1·35 kb poly A+ transcript in Northern blots. The deduced amino acid sequence did not, however, show significant homology with known proteins. The HMc sequence was found only in E. histolytica as it hybridized with 5 different axenic strains of E. histolytica but did not recognize other closely related species of Entamoeba. It has thus the potential to be used as a species-specific DNA probe.
In 12-year (1975–87) fertilizer trial on a pearl millet-wheat rotation, there were no responses to applied K and exchangeable K decreased from 620 to 200 kg/ha. In spite of progressively diminishing exchangeable K, removal of K by crops was independent of soil K status, indicating that exchangeable K had no relation to K uptake in this soil. Thus, nonexchangeable K made a major contribution to plant K, up to 90% in untreated plots and > 70% in K-treated plots. A significant (r = -·708) relationship between nonexchangeable K and K fixation capacity was found. Nonexchangeable K was also significantly but negatively correlated (r = -0·583) with free energy exchange (ΔGr). Potassium supply values, expressed by pK-½p (Ca + Mg), were positively and significantly correlated with K removal by crops in 1987 and with the K saturation values of the exchange phase, so that both these measures can be successfully used to test soil K availability. The results of this study suggested that on this soil, under a pearl millet-wheat crop system, inclusion of K in the fertilizer programme may soon be needed.
In the present analysis, a normal mode approach is used to study waves in a plasma subjected to a spatially uniform but temporally stochastic magnetic field. The first part deals with the evolution of circularly polarized transverse waves. Making a linear analysis, it is shown that the coherent waves are damped. The nature of the damping is determined by the Kubo number. In the second part, the nonlinear interaction of three coherent waves propagating along the magnetic field is analyzed. The coupling coefficients for the interaction of two circularly polarized waves and a longitudinal one are calculated. It is shown that for coherent waves, the system is equivalent to the interaction of two damped transverse modes with an undamped longitudinal one.