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The application of a tube combustion system (pyrolyzer) for the batch combustion of low carbon content environmental matrices, such as soil and sediment, for determining 14C specific activity is examined. The samples were combusted at 600°C, and the CO2 species produced were trapped in 3N NaOH, precipitated as BaCO3 by adding BaCl2, and subjected to acid-hydrolysis to transfer the CO2 species to the absorber-scintillator mixture for liquid scintillation counting (LSC). The method was validated by analyzing the samples by accelerator mass spectrometry (AMS) method. The minimum detectable activity (MDA) for the method, at 2σ confidence level, was 10 Bq kg–1C (4 pMC) for a counting time of 500 min and 7 Bq kg–1C (3 pMC) for 1000 min. The capability of the method to quantify a small excess of 14C specific activity (a few Bq kg–1C or pMC) in the environment of a nuclear facility, when compared to the ambient natural background level, was demonstrated by analyzing a total of 23 soil and 7 sediment samples from the vicinity of a pressurized heavy water reactor (PHWR) nuclear power plant (NPP) at Kaiga, India. The maximum excess 14C specific activity values recorded for soil and sediment matrices were 37 ± 7 Bq kg–1C and 11 ± 7 Bq kg–1C, respectively, confirming minimal radioecological impact of the operation of the NPP on the environment. The 14C specific activity ratio for the recently fallen leaf litter and the soil underneath at most of the sampling points in the vicinity of the NPP had a mean value of 1.03 with an associated standard deviation of 0.07. Statistical tests confirm that the mean values of the data set of 14C specific activity of leaf litter and underlying soil are not significantly different.
The Arcanum mission is a proposed L-class mother-daughter spacecraft configuration for the Neptunian system, the mass and volume of which have been maximised to highlight the wide-ranging science the next generation of launch vehicles will enable. The spacecraft is designed to address a long-neglected but high-value region of the outer Solar System, showing that current advances make such a mission more feasible than ever before. This paper adds to a series on Arcanum and specifically provides progress on the study of areas identified as critical weaknesses by the 2013–2022 decadal survey and areas relevant to the recently published Voyage 2050 recommendations to the European Space Agency (ESA).
Poor academic performance has been linked to factors such as sleep, health, illicit drug use, physical fighting, social media use, cyber bullying, physical activity, homelessness, times spent in video games and television. It is difficult to get a sense of the interplay between and relative importance of different behaviours/factors on academic performance as only limited research has been aimed at quantifying these factors.
Objectives
To evaluate association of school performance and variables in five categories of the YRBSS: physical fighting, diet/lifestyle, electronic device usage, concurrent substance use, and violence/self-harm.
Methods
The CDC Youth Risk Behavior Surveillance System (YRBSS) data from 1991-2019 was used in study. Respondents were grouped by good and poor school performance and variables related to nutrition/lifestyle, electronic device use, concurrent substance use, mood/violence/self-harm were analyzed using chi-square test.
Results
A total of 41,235 student respondents.Nutrition/Lifestyle, electronic device use, concurrent substance use, mood/violence/self-harm are found to be significantly correlated with school performance.
Poor Performance n(%)
Good Performance n(%)
Total n(%)
p-Value
Nutrition/Lifestyle
Daily breakfast
2,715(26)
11,429(38.22)
14,144(35.06)
<0.0001
Sodas ≥2/day
1,998(19.12)
2,710(9.03)
4,708(11.63)
<0.0001
Concurrent Substance Use
Alcohol use
3,544(37.55)
8,067(28.49)
11,611(30.75)
<0.0001
Cigarette smoking
1,616(15.74)
1,845(6.17)
3,461(8.61)
<0.0001
Mood/Violence/Self-Harm
Difficulty concentrating
4,188(46.34)
7,327(28.27)
11,516(32.94)
<0.0001
Felt sad or hopeless
4,373(41.06)
9,038(29.67)
13,410(32.62)
<0.0001
Considered suicide
2,567(24.14)
4,810(15.8)
7,377(17.96)
<0.0001
Conclusions
In national data, we found school performance is affected by nutrition, lifestyle, substance use, mood and exposure to surrounding violence, and self-harm. Further studies should be planned to evaluate benefits from the risk stratification to reduce this burden amongst US adolescents.
Bell's palsy is a lower motor neurone facial weakness of unknown aetiology, although reactivation of a virus within the facial nerve has been proposed.
Methods
A prospective study was conducted of Bell's palsy cases presenting to our paediatric ENT unit over a 19-week period, from February to June 2020. Patients were invited for severe acute respiratory syndrome coronavirus-2 antibody testing. A text-message questionnaire was sent to other ENT centres to determine their observational experience.
Results
During the study period, 17 children presented with Bell's palsy, compared with only 3 children in the same time period in the previous year (p < 0.0001). Five patients underwent severe acute respiratory syndrome coronavirus-2 antibody testing, the results of which were all negative. Four out of 15 centres questioned perceived an increased incidence in paediatric Bell's palsy.
Conclusion
Clinicians are encouraged to be vigilant to the increase in paediatric Bell's palsy seen during the coronavirus disease 2019 pandemic, which may represent a post-viral sequela of coronavirus disease 2019.
The current study was undertaken to identify the sources of tolerance to bruchid in cowpea, by screening a set of germplasm accessions as a source for natural resistance. A total of 103 diverse accessions of cowpea were evaluated for resistance to Callosobruchus maculatus Fab. under no-choice artificial infestation conditions. Significant differences among the cowpea accessions were observed for oviposition, adult emergence, exit holes and per cent seed weight loss (PSWL) caused by the bruchid infestation. The accessions showed variation in physical seed parameters viz., colour, shape, testa texture, length, width and seed hardness. Among the seed biochemical parameters studied, per cent sugar content ranged from 0.322 (IC330950) to 1.493 (IC249137), and per cent phenol content ranged from 0.0326 (EC390261) to 1.081 (EC528423). Correlation studies indicated that PSWL had significant positive correlation (r = 0.335) with exit holes, oviposition (r = 0.219), adult emergence (r = 0.534) and seed roundness (r = 0.219). Adult emergence had a significant negative correlation with seed hardness (r = −0.332). Correlation with biochemical parameters indicated that PSWL had a significant positive correlation (r = 0.231) with sugar content and a significant negative correlation with phenol content (r = −0.219). None of the accessions were found to be immune to bruchid infestation. However, out of studied accessions, EC528425 and EC528387 were identified as resistant based on PSWL and moderately resistant based on adult emergence. These resistance sources of cowpea germplasm can be used as potential donors for development of bruchid tolerant/resistant cultivars.
Coronavirus disease 2019 personal protective equipment has been reported to affect communication in healthcare settings. This study sought to identify those challenges experimentally.
Method
Bamford–Kowal–Bench speech discrimination in noise performance of healthcare workers was tested under simulated background noise conditions from a variety of hospital environments. Candidates were assessed for ability to interpret speech with and without personal protective equipment, with both normal speech and raised voice.
Results
There was a significant difference in speech discrimination scores between normal and personal protective equipment wearing subjects in operating theatre simulated background noise levels (70 dB).
Conclusion
Wearing personal protective equipment can impact communication in healthcare environments. Efforts should be made to remind staff about this burden and to seek alternative communication paradigms, particularly in operating theatre environments.
Background: Biallelic variants in POLR1C are associated with POLR3-related leukodystrophy (POLR3-HLD), or 4H leukodystrophy (Hypomyelination, Hypodontia, Hypogonadotropic Hypogonadism), and Treacher Collins syndrome (TCS). The clinical spectrum of POLR3-HLD caused by variants in this gene has not been described. Methods: A cross-sectional observational study involving 25 centers worldwide was conducted between 2016 and 2018. The clinical, radiologic and molecular features of 23 unreported and previously reported cases of POLR3-HLD caused by POLR1C variants were reviewed. Results: Most participants presented between birth and age 6 years with motor difficulties. Neurological deterioration was seen during childhood, suggesting a more severe phenotype than previously described. The dental, ocular and endocrine features often seen in POLR3-HLD were not invariably present. Five patients (22%) had a combination of hypomyelinating leukodystrophy and abnormal craniofacial development, including one individual with clear TCS features. Several cases did not exhibit all the typical radiologic characteristics of POLR3-HLD. A total of 29 different pathogenic variants in POLR1C were identified, including 13 new disease-causing variants. Conclusions: Based on the largest cohort of patients to date, these results suggest novel characteristics of POLR1C-related disorder, with a spectrum of clinical involvement characterized by hypomyelinating leukodystrophy with or without abnormal craniofacial development reminiscent of TCS.
Manipur, an international border region has the highest incidence of human immunodeficiency virus (HIV)-1 infection in India. Nevertheless, there have been no analytical reviews of research article published within this region. In this review, the authors aim to draw the attention of policy makers, medical practitioners and researchers in adopting new strategies to limit the expansion of HIV/acquired immunodeficiency syndrome (AIDS) not only in Manipur but also in other international border areas. A systematic search for published literature in last decade was performed based on the keywords ‘Manipur’ and ‘HIV’ using the PubMed. Twenty-six articles were selected and reviewed. There were high incidence of drug resistance (53%), emergence of recombinant virus (32%) and increased incidence of co-infection with hepatitis C virus. The prime cause of the HIV is due to the uses of ‘heroin’ smuggled from the ‘South Asia Golden Triangle’ and complex patterns of cross-border movement for trade and commerce. The drug abuse, social stigma, geographical location and resource limitation and socio-political problem of the region have contributed strongly on spreading and failure of preventively programme of HIV/AIDS. This review will provide vital knowledge for the policy makers and clinicians for sentinel surveillance of AIDS pandemic in Manipur and other international border regions.
Obstructive sleep apnoea is a common chronic sleep disorder characterised by collapse of the upper airway during sleep. The nasal airway forms a significant part of the upper airway and any obstruction is thought to have an impact on obstructive sleep apnoea. A systematic review was performed to determine the role of rhinological surgical interventions in the management of obstructive sleep apnoea.
Methods
A systematic review of current literature was undertaken; studies were included if they involved comparison of a non-surgical and/or non-rhinological surgical intervention with a rhinological surgical intervention for treatment of obstructive sleep apnoea.
Results
Sixteen studies met the selection criteria. The pooled data suggest that there are reductions in the apnoea/hypopnea index and respiratory disturbance index following nasal surgery. However, the current body of studies is too heterogeneous for statistically significant meta-analysis to be conducted.
Conclusion
Nasal surgery may have limited benefit for a subset of patients based on current evidence.
Mental health and wellbeing, including addressing impacts of historical trauma and substance use among young people, has been identified as a key priority by Indigenous communities and leaders across Canada and globally. Yet, research to understand mental health among young Indigenous people who have used drugs is limited.
Aims.
To examine longitudinal risk and strengths-based factors associated with psychological distress among young Indigenous people who use drugs.
Method.
The Cedar Project is an ongoing cohort study involving young Indigenous people who use drugs in Vancouver, Prince George, and Chase, British Columbia, Canada. This study included participants who completed the Symptom Checklist-90-Revised, returned for follow-up between 2010 and 2012, and completed the Childhood Trauma Questionnaire. Adjusted linear mixed-effects models estimated effects of study variables on changes in area T-scores of psychological distress.
Results.
Of 202 eligible participants, 53% were women and the mean age was 28 years. Among men, childhood maltreatment (emotional abuse, physical abuse, sexual abuse, physical neglect), any drug use, blackouts from drinking, and sex work were associated with increased distress. Among women, childhood maltreatment (emotional abuse, physical abuse, physical neglect), blackouts from drinking, and sexual assault were associated with increased distress, while having attempted to quit using drugs was associated with reduced distress. Marginal associations were observed between speaking their traditional language and living by traditional culture with lower distress among men.
Conclusion.
Culturally safe mental wellness interventions are urgently needed to address childhood trauma and harmful coping strategies that exacerbate distress among young Indigenous people who use drugs.
The study primarily aimed to calculate the orientation of the cochlea pre-operatively, using high-resolution computed tomography of the temporal bone, and predict the ease of electrode insertion.
Methods
Pre-operatively, high-resolution computed tomography scans were conducted on children scheduled for cochlear implantation, and two angles, α and β, were calculated. The values of α and β were then correlated with intra-operative difficulty in insertion of the electrode array.
Results
Ninety-six children were included in the study. Of the seven patients who had an α angle of less than 50 degrees, the surgeon experienced difficulties in electrode insertion. However, there were four patients with an α angle of more than 50 degrees for whom the surgeon also experienced difficulties in electrode insertion. In all these patients, the β angle was more than 20 degrees.
Conclusion
Calculation of cochlear orientation and its angle with the surgical axis (α and β) can aid the planning of surgery, particularly with regard to the cochleostomy site and preservation of residual hearing.
The Global Muon Detector Network (GMDN) is composed by four ground cosmic ray detectors distributed around the Earth: Nagoya (Japan), Hobart (Australia), Sao Martinho da Serra (Brazil) and Kuwait city (Kuwait). The network has operated since March 2006. It has been upgraded a few times, increasing its detection area. Each detector is sensitive to muons produced by the interactions of ~50 GeV Galactic Cosmic Rays (GCR) with the Earth′s atmosphere. At these energies, GCR are known to be affected by interplanetary disturbances in the vicinity of the earth. Of special interest are the interplanetary counterparts of coronal mass ejections (ICMEs) and their driven shocks because they are known to be the main origins of geomagnetic storms. It has been observed that these ICMEs produce changes in the cosmic ray gradient, which can be measured by GMDN observations. In terms of applications for space weather, some attempts have been made to use GMDN for forecasting ICME arrival at the earth with lead times of the order of few hours. Scientific space weather studies benefit the most from the GMDN network. As an example, studies have been able to determine ICME orientation at the earth using cosmic ray gradient. Such determinations are of crucial importance for southward interplanetary magnetic field estimates, as well as ICME rotation.
Lower and middle income countries (LMICs) are home to >80% of the global population, but mental health researchers and LMIC investigator led publications are concentrated in 10% of LMICs. Increasing research and research outputs, such as in the form of peer reviewed publications, require increased capacity building (CB) opportunities in LMICs. The National Institute of Mental Health (NIMH) initiative, Collaborative Hubs for International Research on Mental Health reaches across five regional ‘hubs’ established in LMICs, to provide training and support for emerging researchers through hub-specific CB activities. This paper describes the range of CB activities, the process of monitoring, and the early outcomes of CB activities conducted by the five research hubs.
Methods
The indicators used to describe the nature, the monitoring, and the early outcomes of CB activities were developed collectively by the members of an inter-hub CB workgroup representing all five hubs. These indicators included but were not limited to courses, publications, and grants.
Results
Results for all indicators demonstrate a wide range of feasible CB activities. The five hubs were successful in providing at least one and the majority several courses; 13 CB recipient-led articles were accepted for publication; and nine grant applications were successful.
Conclusions
The hubs were successful in providing CB recipients with a wide range of CB activities. The challenge remains to ensure ongoing CB of mental health researchers in LMICs, and in particular, to sustain the CB efforts of the five hubs after the termination of NIMH funding.
In search of a suitable resource conservation technology under pigeonpea (Cajanus cajan L.)–wheat (Triticum aestivum L.) system in the Indo-Gangetic Plains, the effects of conservation agriculture (CA) on crop productivity and water-use efficiency (WUE) were evaluated during a 3-year study. The treatments were: conventional tillage (CT), zero tillage (ZT) with planting on permanent narrow beds (PNB), PNB with residue (PNB + R), ZT with planting on permanent broad beds (PBB) and PBB + R. The PBB + R plots had higher pigeonpea grain yield than the CT plots in all 3 years. However, wheat grain yields under all plots were similar in all years except for PBB + R plots in the second year, which had higher wheat yield than CT plots. The contrast analysis showed that pigeonpea grain yield of CA plots was significantly higher than CT plots in the first year. However, both pigeonpea and wheat grain yields during the last 2 years under CA and CT plots were similar. The PBB + R plots had higher system WUE than the CT plots in the second and third years. Plots under CA had significantly higher WUE and significantly lower water use than CT plots in these years. The PBB + R plots had higher WUE than PNB + R and PNB plots. Also, the PBB plots had higher WUE than PNB in the second and third years, despite similar water use. The interactions of bed width and residue management for all parameters in the second and third years were not significant. Those positive impacts under PBB + R plots over CT plots were perceived to be due to no tillage and significantly higher amount of estimated residue retention. Thus, both PBB and PBB + R technologies would be very useful under a pigeonpea–wheat cropping system in this region.
Expressed sequence tag-simple sequence repeat (EST-SSR) markers were used to analyse genetic diversity among three Lens species. The SSR loci amplified successfully in wild species, with 94·82% transferability in Lens culinaris subsp. orientalis, 95·4% in Lens nigricans, 98·81% in L. culinaris subsp. odemensis, 94·82% in L. culinaris subsp. tomentosus and 96·55% in Lens ervoides. Ninety-nine alleles (average 3·41 alleles/locus) were detected by 29 SSR markers. Based on the unweighted pair group method with arithmetic mean cluster analysis, all the genotypes were grouped into three clusters at a similarity level of 0·30. The diversity analysis indicated no species-specific clustering of the wild and cultivated species. Wild species L. nigricans and L. culinaris subsp. odemensis, L. culinaris subsp. orientalis and L. ervoides were grouped in Cluster I, whereas the Mediterranean land races of L. culinaris subsp. culinaris and L. culinaris subsp. tomentosus formed a separate group in Cluster II A. Cluster II B comprised L. ervoides, L. culinaris subsp. orientalis and L. culinaris subsp. culinaris. Clusters II C, II D and II F included cultivated Indian lentil genotypes. Cluster II E comprised Indian and Mediterranean germplasm lines. Cluster II F included three early maturing germplasm lines, whereas Cluster III included only two germplasm lines. The functional annotation of SSR-containing unigenes revealed that a majority of genes were involved in an important transport-related function or were a component of metabolic pathways. A high level of polymorphism of EST-SSRs and their transferability to related wild species indicated that these markers could be used for molecular screening, map construction, comparative genomic studies and marker-assisted selection.