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From the 1918 influenza pandemic (H1N1) until the recent 2019 severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic, no efficient diagnostic tools have been developed for sensitive identification of viral pathogens. Rigorous, early, and accurate detection of viral pathogens is not only linked to preventing transmission but also to timely treatment and monitoring of drug resistance. Reverse transcription-polymerase chain reaction (RT-PCR), the gold standard method for microbiology and virology testing, suffers from both false-negative and false-positive results arising from the detection limit, contamination of samples/templates, exponential DNA amplification, and variation of viral ribonucleic acid sequences within a single individual during the course of the infection. Rapid, sensitive, and label-free detection of SARS-CoV-2 can provide a first line of defense against the current pandemic. A promising technique is non-linear coherent anti-Stokes Raman scattering (CARS) microscopy, which has the ability to capture rich spatiotemporal structural and functional information at a high acquisition speed in a label-free manner from a biological system. Raman scattering is a process in which the distinctive spectral signatures associated with light-sample interaction provide information on the chemical composition of the sample. In this prospective, we briefly discuss the development and future prospects of CARS for real-time multiplexed label-free detection of SARS-CoV-2 pathogens.
Artificial insemination (AI) technology use in poultry production has enabled the rapid dissemination of genetic material from a small number of superior males to a high number of females. Excellent fertility in poultry can be obtained by AI compared to natural mating. Successful application of this technique needs good quality semen that should be inseminated very close to the sperm storage tubules in the female to obtain the optimum fertility in chicken. Since the 1950s, AI has been used in commercial poultry production, initially in Israel and Australia, followed by the USA. Doses of spermatozoa required for AI increases with storage time or that obtained from aged bird. The average volume of semen is between 0.05-0.50 ml in light chicken breeds and 0.1-0.9 ml in heavy males. In light turkeys, volume is 0.08-0.30 ml, whereas in heavy-weight males it is 0.1-0.33 ml. Quality evaluation of semen gives an indication of the male reproductive potential and is the major determinant of fertility and subsequently hatchability of eggs. Semen from cockerels contains between 3-7 billion sperm cells/ml. Among the several factors that influence the semen quality, sperm motility is a primary determinant of fertility in domestic fowls; however, visual examination of semen cannot be ignored for successful AI under field conditions. Dilution of low and viscous volume of avian semen is essential for handling and storage, and chicken semen typically requires a two to three-fold dilution. Collected samples should be preserved at 2-8°C for avian species, ideally with turkey sperm stored at 4-8°C, and chicken semen at 7-8°C for good fertility. Currently, the technique of AI in most of the poultry species is well developed; however, there is a need for successful development programme of this technique in non-domesticated birds to assist in creating viable, self-sustaining populations of critically endangered species.
Improving understanding of the pathogen-specific seasonality of enteric infections is critical to informing policy on the timing of preventive measures and to forecast trends in the burden of diarrhoeal disease. Data obtained from active surveillance of cohorts can capture the underlying infection status as transmission occurs in the community. The purpose of this study was to characterise rotavirus seasonality in eight different locations while adjusting for age, calendar time and within-subject clustering of episodes by applying an adapted Serfling model approach to data from a multi-site cohort study. In the Bangladesh and Peru sites, within-subject clustering was high, with more than half of infants who experienced one rotavirus infection going on to experience a second and more than 20% experiencing a third. In the five sites that are in countries that had not introduced the rotavirus vaccine, the model predicted a primary peak in prevalence during the dry season and, in three of these, a secondary peak during the rainy season. The patterns predicted by this approach are broadly congruent with several emerging hypotheses about rotavirus transmission and are consistent for both symptomatic and asymptomatic rotavirus episodes. These findings have practical implications for programme design, but caution should be exercised in deriving inferences about the underlying pathways driving these trends, particularly when extending the approach to other pathogens.
The merits of solar coronal at metric-wavelength (MW) radio have long been recognised (e.g. Pick and Vilmer, 2008). High-fidelity solar radio imaging at these frequencies has however remained challenging. On the one hand, dealing with the small spectral and temporal scales of variation in solar radio emission requires a data product capable of tracking the emission simultaneously across time, frequency and morphology. The Fourier imaging nature of interferometry, on the other hand, severely limits the instrumental ability to gather sufficient information to do this with the required fidelity and resolution. Benefiting from the enormous advances in technology the new generation of instruments, like the Murchison Widefield Array (MWA; Tingay et al. (2013), Bowman et al. (2013)), represent a quantum leap in our ability to gather data suitable for radio solar physics.
At low radio frequencies the solar corona is very dynamic in both spectral and temporal domains. To capture the fine details of this complex dynamics, imaging studies at high temporal and spectral resolution are necessary. The advent of the new instruments like the Murchison Widefield Array (MWA; Tingay et al. 2013, Bowman et al. 2013), is now making this possible.
In birds, after natural mating or artificial insemination (AI), sperms are transported through cloaca or vagina at the utero-vaginal junction (UVJ) of oviduct. Only 1% of the deposited sperm passes through the selection process in the vagina to reach the UVJ. In the UVJ, sperm enter the tubular invagination of the surface epithelium of the mucosa collectively called ‘sperm storage tubules’ (SSTs) where they are stored for longer duration retaining their fertilising capacity. The storage capacity and duration varies from species to species. This enables the birds to produce fertile eggs continuously. Shortly before and during egg production, sperm residing in the SST upon release will ascend the oviduct to the site of fertilisation in the infundibulum. Within the SSTs, sperm motility is suppressed and is initiated at some stage before fertilisation. Restoration of sperm motility is necessary for the release of spermatozoa from the SSTs. The exact mechanism by which sperm are stored in these tubules and released has not been established and hence, this is the focus of this review.
To estimate the proportion of products meeting Indian government labelling regulations and to examine the Na levels in packaged foods sold in India.
Nutritional composition data were collected from the labels of all packaged food products sold at Indian supermarkets in between 2012 and 2014. Proportions of products compliant with the Food Safety Standards Authority of India (FSSAI) regulations and labelled with Na content, and mean Na levels were calculated. Comparisons were made against 2010 data from Hyderabad and against the UK Department of Health (DoH) 2017 Na targets.
Eleven large chain retail stores in Delhi and Hyderabad, India.
Packaged food products (n 5686) categorised into fourteen food groups, thirty-three food categories and ninety sub-categories.
More packaged food products (43 v. 34 %; P<0·001) were compliant with FSSAI regulations but less (32 v. 38 %; P<0·001) reported Na values compared with 2010. Food groups with the highest Na content were sauces and spreads (2217 mg/100 g) and convenience foods (1344 mg/100 g). Mean Na content in 2014 was higher in four food groups compared with 2010 and lower in none (P<0·05). Only 27 % of foods in sub-categories for which there are UK DoH benchmarks had Na levels below the targets.
Compliance with nutrient labelling in India is improving but remains low. Many packaged food products have high levels of Na and there is no evidence that Indian packaged foods are becoming less salty.
Introduction: Weight concerns may inhibit smoking quit attempts and may be more influential amongst African-Americans who are more likely to be overweight.
Aims: To assess if weight perception is associated with readiness to quit and whether this relationship is modified by race.
Methods: We used data from a cohort of current smokers undergoing routine health examinations. Based on differences between ideal and measured BMI, participants’ weight perceptions were classified as within, somewhat above, or far above ideal weight. Logistic regression analysis was used to evaluate adjusted associations of weight perception and race with readiness to quit.
Results: Of 2,831 current smokers, 23% were obese and 38% overweight. Amongst white smokers, those who perceived being far above ideal weight were more likely to be ready to quit (OR: 1.45, 95% CI: 1.03–2.03), but this association was not observed for African-American smokers who perceived themselves to be somewhat or far above their ideal weight (OR: 0.35, 95% CI: 0.10–1.24 and OR: 0.36, 95% CI: 0.11–1.19, respectively).
Conclusions: Perception of being overweight is associated with increased readiness to quit amongst white but not African-American smokers. Smoking cessation programmes may need to culturally tailor interventions based on smokers’ weight perceptions.
The Evolutionary Map of the Universe (EMU) is a proposed radio continuum survey
of the Southern Hemisphere up to declination + 30°, with the Australian
Square Kilometre Array Pathfinder (ASKAP). EMU will use an automated source
identification and measurement approach that is demonstrably optimal, to
maximise the reliability and robustness of the resulting radio source
catalogues. As a step toward this goal we conducted a “Data
Challenge” to test a variety of source finders on simulated images. The
aim is to quantify the accuracy and limitations of existing automated source
finding and measurement approaches. The Challenge initiators also tested the
current ASKAPsoft source-finding tool to establish how it could benefit from
incorporating successful features of the other tools. As expected, most finders
show completeness around 100% at ≈ 10σ dropping to about 10% by
≈ 5σ. Reliability is typically close to 100% at ≈
10σ, with performance to lower sensitivities varying between finders. All
finders show the expected trade-off, where a high completeness at low
signal-to-noise gives a corresponding reduction in reliability, and vice versa.
We conclude with a series of recommendations for improving the performance of
the ASKAPsoft source-finding tool.
Background and Purpose: Carotid artery stenting (CAS) has been, historically, an alternative to open endarterectomy (CEA) for stroke prevention in high risk patients with carotid atherosclerosis. We sought to determine the rates of periprocedural and long-term stroke or death and the risk factors for complications after CAS in our high risk patient population. Methods: Clinical and treatment variables of consecutive CAS procedures performed between 2002 and 2011 were analyzed. Using univariate and multivariate logistic regression analyses we examined how patient characteristics influenced outcomes and changes in modified Rankin Score (mRS). Results: In 152 patients, the composite total of periprocedural death, stroke, transient ischemic attack (TIA) and myocardial infarction (MI) rate was 3.95% (6/152). Chronic kidney disease (CKD) was strongly associated with periprocedural complications (p<0.001). Coronary artery disease/peripheral vascular disease (CAD/PVD) (p=0.03), dyslipidemia (p=0.02), CKD (p=0.01), and contralateral internal carotid artery stenosis (p=0.02) were non-modifiable risk factors for mRS increase. There were 25 deaths, 8 strokes, 11 TIAs, and 1 MI (mean follow-up 38.4 months, range 0-116 months). The presence of CAD/PVD (p=0.009) and dyslipidemia (p=0.002) were significantly associated with long-term complications. Conclusion: CAS was performed with low periprocedural complications in high-risk patients. Our rates compare very favorably to large-scale trials that have ideal patients. This data encourages the consideration of CAS in patients considered high risk for CEA and provides possible patient characteristics (CKD) to help with periprocedural risk stratification.
Gallium nitride (n-type) films of thickness 300nm were grown on c-plane sapphire substrates using plasma assisted molecular beam epitaxy (PA-MBE). High resolution X-ray diffraction and photoluminescence measurements were used to confirm the crystalline and optical qualities of the grown films. Metal-semiconductor Schottky diodes were fabricated using Pt as the Schottky metal and Al as the Ohmic metal contact. Metal-insulator-semiconductor Schottky diodes were also fabricated using HfO2 (10nm) as the insulator material. Diode parameters like barrier height and ideality factor were extracted from I-V measurements. Introduction of HfO2 as the insulator layer leads to better rectifying behavior (forward to reverse current ratio improves from 5.1 to 8.9) with a reduction in reverse leakage current (by 7.4 times), increase in barrier height (from 0.62eV to 0.74eV) and a reduction in ideality factor (from 6 to 4.1) of the Schottky diode.
Estimating robot performance in human robot teams is a vital problem in human robot interaction community. In a previous work, we presented extended neglect tolerance model for estimation of robot performance, where the human operator switches control between robots sequentially based on acceptable performance levels, taking into account any false alarms in human robot interactions. Task complexity is a key parameter that directly impacts the robot performance as well as the false alarms occurrences. In this paper, we validate the extended neglect tolerance model for two robot tasks of varying complexity levels. We also present the impact of task complexity on robot performance estimations and false alarms demands. Experiments were performed with real and virtual humanoid soccer robots across tele-operated and semi-autonomous modes of autonomy. Measured false alarm demand and robot performances were largely consistent with the extended neglect tolerance model predictions for both real and virtual robot experiments. Experiments also showed that the task complexity is directly proportional to false alarm demands and inversely proportional to robot performance.
In 1978, 22 staff members of the National Institute of Virology, Pune, India, were given two doses of human diploid cell antirabies vaccine (HDCV) for primary pre-exposure prophylactic immunization; the interval between the two doses being approximately 4 weeks. Eighteen of these 22 vaccinees were given a booster dose 1 year later. All 18 vaccinees developed protective levels of antibody; most of them had antibody levels exceeding 10 IU/ml.
In 1984, 5 years after the booster dose, 11 (79·0%) of 14 vaccinees tested still possessed neutralizing antibody levels ranging from 0·5 IU/ml to 10 IU/ml. Fourteen days after the administration of a booster dose, the antibody levels ranged from 10 to ≥ 100 IU/ml for all except one vaccinee (5·2 IU/ml). These findings demonstrate that the majority of vaccinees retained detectable neutralizing antibody after pre-exposure prophylaxis for as long as 5 years and that a single booster dose thereafter evoked a good antibody response.
Considerable difference of opinion has existed as to whether the incidence of cancer is at all affected by the habits of life of different classes of the community. There is of course no doubt that in certain occupations particular forms of malignant disease are exceptionally prevalent, the case of chimney sweeps being notorious; but the more general question as to the incidence on large groups of occupations has not been so definitely determined. The present research was suggested by the apparently contradictory results obtained by Heron from his study of London statistics, and by Maynard from an analysis of United States data.
Constitute hypothesis for origin of supernumerary phantom limb (SPL) after stroke.
Single case description, review of literature and formulation of hypothesis.
A 59-year-old lady was evaluated for complaints of left-sided hemiparesis and extra limbs attached to her left shoulder for the past 7 months. Neuropsychological assessment revealed left hemineglect with SPL, and profile suggested bilateral frontal, right parietotemporal and basal ganglia involvement. Magnetic resonance imaging brain scan showed gliotic cavity secondary to the old haematoma in right putamen with white matter changes in the right frontoparietotemporal lobes.
The conceptual framework of body schema can be used to classify many of the neurological disorders of body representation. Generation of SPL comes under the subtype of pathology of updating among the disorders of body schema. The continuous updating allows the body schema to modulate perceptual processing of objects according to their position in space. Brain areas classified as parts of motor system can, under pathological conditions (haemorrhage), influence body perception. So, when she used to move her arm, the representation of the estimated position was not updated by the motor commands. Sensory and motor information therefore becomes discrepant, and failure to integrate these two sources of information leads to loss of normal coherence, and the perceived shape of the body was altered by adding a SPL to accommodate the discrepancy.
The potential environmental and health concerns surrounding actinides and the use of nuclear fuels limits the acceptance of nuclear power by the public. This in turn, hinders the capability of this country to take advantage of nuclear power. Expanding our fundamental knowledge of actinide coordination chemistry will allow for the development of improved actinide sensors, new separations methods, or new means of radioactive waste remediation. We have designed and optimized a solution-phase parallel method for the synthesis of a library of symmetrical 2-quinoxalinol salens, Schiff-base type ligands with a 2-quinoxalinol incorporated into the salen backbone. This combines the rigid salen coordination framework with the quinoxaline properties that impart properties for use in colorimetric or fluorescent sensors. These have now been incorporated into organic soluble resins for metal extraction.