Population-wide genetic analysis of Ovar-DQA1 and DQA2 loci across sheep breeds in India revealed their evolutionary importance and fitness of sheep in a tropical climate.

Genetic variability at the major histocompatibility complex (MHC) is important in any species due to significant role played by MHC for antigen presentation. DQA locus has not been studied for its genetic variability across sheep population in India. In the present study, MHC of sheep at DQA1 and DQA2 loci were evaluated across 17 Indian sheep breeds. Results revealed high degree of heterozygosity (10.34% to 100% for DQA1 and 37.39 to 100% for DQA2). 18 DQA1 alleles and 22 DQA2 alleles were isolated in different breeds. Nucleotide content for DQA region revealed richness of AT content (54.85% for DQA1 and 53.89% for DQA2). DQA1 and DQA2 sequences clustered independently. We could see evidence of divergence of DQA as DQA1 and DQA2 across sheep breeds. Wu-Kabat variability index revealed vast genetic variation across DQA1 and DQA2, specifically at peptide binding sites (PBS) that consisted 21 residues for DQA1 and 17 residues for DQA2. Evolutionary analysis revealed the presence of positive and balancing selection for DQA1 locus, however DQA2 was under purifying selection across sheep breeds. Higher heterozygosity and large diversity at both loci especially at PBS indicated the fitness of the sheep population for evading pathogens and adapt to the harsh tropical climate.

Cross-population genetic analysis revealed genetic variation and selection in the Ovar-DRB1 gene of Indian sheep breeds.

In sheep, MHC variability is studied widely to explore disease association. The aim of the current study was to explore the genetic diversity of Ovar-DRB diversity across sheep breeds of India. Here, Ovar-DRB1 locus was studied across 20 sheep breeds. DRB1 was amplified (301 bp) and sequenced using a PCR-sequence-based typing approach. Results revealed a high degree of heterozygosity across breeds (mean: 73.99%). Overall mean distance for DRB1 was highest in Sangamneri (0.18) and lowest in Madgyal sheep (0.10). There was a higher rate of transition, across breeds. Further, 39 alleles were isolated in different breeds, out of which 10 were new. To allow easy access and use of the immune-polymorphic database, an online database management system was launched (http://www.mhcdbms.in/). Nucleotide content across breeds for the DRB1 region revealed the richness of GC content (59.26%). Wu-Kabat index revealed vast genetic variation across peptide binding sites (PBS) of DRB1. Residues 6, 66, 69, 52, and 81, were polymorphic showing utility for antigen presentation. All breeds were under positive selection for DRB1 locus (dN > dS). Study revealed the importance of DRB locus diversity for beta chain specifically at PBS across sheep breeds of the Indian subcontinent and presented evidence of positive selection for DRB owing to its evolutionary significance.

Prevalence of night eating syndrome among inbound call centre employees in Kuala Lumpur, Malaysia.

Background: Night eating syndrome (NES) is described as a disordered eating pattern relative to sleep, where consumption of food occurs in the evening and night. Numerous studies had been conducted in various populations but studies on (NES) among call centre employees are limited. Aim: This study aimed to determine the prevalence of NES and its determinants among selected inbound call centre employees in Kuala Lumpur, Malaysia. Methods: In this cross-sectional study, a total of 217 inbound call centre employees were recruited through random sampling. A self-administered socio-demographic and work-related questionnaire was used to collect data on the background of the respondents. Information on NES and well-being was obtained by using the Night Eating Questionnaire (NEQ) and World Health Organisation-Five Well-Being Index (WHO-5) respectively. Data on dietary intakes, smoking habits, alcohol intakes and life stress were acquired using a Simple Lifestyle Indicator Questionnaire (SLIQ) while eating behaviour of the respondents was studied using the Three-Factor Eating Questionnaire (TFEQ-18). Results: The mean age of the respondents was 24.1 ± 6.0 years. The prevalence of NES was 12.0% (95% CI = 8.12-17.24). The binary logistic regression identified that NES is significantly associated with adequate exercise (AOR = 4.250, p = 0.012) and emotional eating (AOR = 6.510, p = 0.014). Conclusion: This study showed that the prevalence of NES was high in the call centre and repeated nocturnal eating can have multiple adverse health effects. Therefore, promoting healthy eating habits are crucial to reduce the impacts of NES.

Clinical Utility of Intravascular Ultrasound (IVUS) in Carotid Artery Interventions: A Systematic Review and Meta-analysis.

BACKGROUND: Carotid plaque morphology plays an important role in determining outcome of carotid artery stenting (CAS). Intravascular ultrasound (IVUS) and its extension VH (Virtual Histology)-IVUS evaluate plaque characteristics in real time and guide decision making during stenting. To date, there is no consensus about indications of IVUS and its validated methods. This systematic review and meta-analysis aims to evaluate the clinical utility of IVUS in carotid artery interventions (CAS) and develop a future consensus for research and practice parameters. METHODS: A systematic review and meta-analysis was performed of the English literature articles published till February 2021. Studies reporting on IVUS parameters and findings and also its performance compared with other imaging modalities were included in review. Pooled prevalence with 95% confidence intervals (CI) was calculated. The statistical analysis was conducted in R version 3.6.2. RESULTS: A total of 2015 patients from 29 studies were included. Proportional meta-analysis was performed on 1566 patients from 11 studies. In 9 studies, stroke/transient ischemic attack (TIA) had a pooled prevalence of 4% (95% CI 3%-5%) while asymptomatic stroke had a pooled prevalence of 46% (95% CI 31%-62%) in 4 studies following IVUS. Two studies reported that IVUS detected more plaque protrusion compared with angiography (n=33/396 vs 11/396). IVUS led to stent type or size change in 8 of 48 cases which were missed on angiography in 3 other studies. Concordance between VH-IVUS and true histology was good at 80% to 85% reported in 2 studies. CONCLUSIONS: This systematic review and meta-analysis showed, though IVUS fared better to computed tomography (CT)/magnetic resonance (MR) angiography for better stent selection during CAS, with low to moderate risk of bias in the studies included. However, large scale, preferably randomized controlled studies are needed to predict its role in determining clinical outcome.

Isolation, purification and structural elucidation of Mellein from endophytic fungus Lasiodiplodia theobromae strain (SJF-1) and its broad-spectrum antimicrobial and pharmacological properties.

In an on-going investigation of bioactive metabolites producing potential endophytic fungi, the strain Lasiodiplodia theobromae (SJF-1) was isolated from a medicinal plant Syzygium cumini. The cultural, morphological and molecular identification was done with the SJF-1 strain. The obtained gene sequence was deposited in NCBI with accession number MG 938644. The methanolic extract of SJF-1 strain possessed one major bioactive fraction, and it was purified by column chromatography. Further, it was identified as Mellein by various spectroscopic studies (1 H, 13 C, DEPT-135°, FT-IR, ESI-HR-MS and 2D NMR). Biologically, Mellein showed potent anti-Xanthomonas activity with minimum inhibitory concentration (MIC) values ranging from 1·9 to 62·5 µg ml-1 against 11 Xanthomonas strains, a broad-spectrum antimicrobial activity with MIC 7·8-31·25 µg ml-1 and 1·9-31·25 µg ml-1 towards both bacterial and fungal strains, respectively. The scanning electron microscope analysis proved the antimicrobial efficacy of a Mellein by rupturing the cell walls of Xanthomonas sp. Molecular docking studies further supported that the Mellein showed good binding interactions with the proteins of Xanthomonas sp. to reduce pathogenicity. Further, in silico pharmacological studies showed that this metabolite exhibited high gastrointestinal absorption properties and promising oral drug bioavailability. We report, anti-Xanthomonas, in silico docking and pharmacological studies of Mellein from (SJF-1) strain for the first time.

Role of probiotics in adjunct to non-surgical periodontal therapy in patients with chronic periodontitis: a systematic review and meta-analysis.

The objective of this study was to establish the significance of probiotic usage, both as a preventive as well as a therapeutic strategy for the management of periodontal disease. It also substantiates the existing studies of single/combined bacterial strain for exhibiting variable ecological impact on oral bacteria. Data sources included literature searches of PubMed (MEDLINE), Scopus, Embase, CENTRAL and Web of science databases for placebo controlled randomized clinical trials of SRP with orally administered probiotics in any form as an adjunct. Data extraction was conducted and information from the included studies was tabulated according to the study designs, form of drug delivery, main outcomes, and clinical parameters. Data collected were based on the focused question outlined for the present systematic review. The reviewers cross-checked all extracted data. CAL and PD were assessed as the primary outcome to compare the effectiveness of adjunctive probiotic therapy in addition to SRP. Fourteen clinical studies were included and demonstrated efficacy in reducing periodontal probing depth (PPD) and gaining clinical attachment level (CAL), between probiotics and SRP/placebo. Adjunctive probiotic therapy in addition to SRP leads to decrease in probing depth and clinical attachment gain in chronic periodontitis patients. However, further high-quality randomized clinical trials with microbiological outcomes are required to fortify the conclusion.

Effects of a randomized controlled trial of a brief, student-nurse led, parent-based sexual health intervention on parental protective factors and HPV vaccination uptake.

BACKGROUND: Parents play a pivotal role in adolescent sexual health and Human Papillomavirus (HPV) vaccination. Nurses are on the frontlines of healthcare and play a critical role in promoting HPV vaccination and parent-child sexual health communication. We enhanced the Families Talking Together (FTT) parent-based sexual health curriculum to include adolescent vaccinations herein, FTT + HPV, and trained student nurses to provide a strong HPV vaccination and parent-child sexual health communication endorsement. METHODS: Using a randomized attention-controlled trial design, we examined the efficacy of FTT + HPV among 519 parents and their 11-14 year old youth recruited from medically underserved communities between 2015 and 2018. Participants were recruited from 22 after-school programs (e.g., Boys and Girls Clubs) and 19 charter schools. For parents, we examined protective factors including parent-child sexual health communication and parental involvement. For youth, we examined sexual health knowledge, parent-child sexual health communication, and parent-child connectedness. To assess HPV vaccination initiation and completion, we searched IMMTRAC immunization registry records for 85% of youth and used parental report for youth without registry records. Group differences were calculated using the estimated mean difference at one- and six months post-intervention with significance set at the p < 0.05 level. RESULTS: Baseline rates of HPV vaccination were low at 55.7%. No significant difference between the groups was seen in vaccination initiation or completion rates by one-month post-intervention. However, by six-months post intervention, there was a significant difference between the groups with 70.3% of the intervention group initiating the HPV vaccination series vs. 60.6% for the control group (p = 0.02). No difference between the groups was found for HPV series completion at six-months. There were significant differences in condom knowledge (p = 0.04), parent-child connectedness (p = 0.04), and communication frequency (p = 0.001) with greater improvement in the intervention vs. the control group. Rates of sexual activity remained low in both groups throughout the six-month follow-up period. CONCLUSION: A brief parent-based adolescent sexual health and HPV vaccination intervention delivered by student nurses can improve sexual health outcomes including protective parental factors, adolescent sexual health knowledge, and HPV vaccination initiation rates. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT02600884 . Prospectively registered September 1, 2015.

Recurrent aplastic anemia with donor-type aplasia: A rare occurrence in the Indian subcontinent.

Donor-type aplasia (DTA) is a condition where an individual continues to be aplastic even after a successful engraftment of a hematopoeitic stem cell transplant with a majority of donor type cells in the bone marrow. This entity has been seen with varying frequency around the world, especially in Southeast Asia. However, its incidence in the Indian subcontinent remains fairly low. Here is a case of a 17-year-old child with DTA who had a 89% population of donor cells after a successful transplant and presented with recurrent severe aplastic anemia later. The patient eventually succumbed to his condition before a second transplant could be performed. The awareness about the seriousness of this relatively rare condition, therefore, needs to be emphasized.

Farmer's participatory approach for breed improvement in Malpura sheep.

The objective of the study was to propose a model for a community-based breeding programme (CBBP) in Malpura sheep. The study was carried out for nine years (2012-2018) in 31 villages covering 77 flocks. The average flock size was 54.39 ± 0.65. The study revealed that the Malpura sheep is a long-day breeder with 72.1% of lambing during August to January. The higher concentration of lambing in this period is to avoid the stress of harsh summer and scarcity of feed. The disposal pattern of male lambs was stringent due to selection. Only 3.1% of male lambs reach to adult stage. For females, the replacement rate was 34.11%. The live weights (kg) from 8,263 lambs were 3.34 ± 0.01, 14.61 ± 0.04, 20.48 ± 0.07 and 30.01 ± 0.16, for birth, three-, six- and 12-month age, respectively. Non-genetic factors such as sex, season and year of birth and flock significantly influenced growth. The heritability was 0.20 ± 0.03, 0.20 ± 0.008, 0.23 ± 0.004 and 0.17 ± 0.009 for birth, three-, six- and 12-month weight, respectively. This indicated scope for genetic improvement, given a systematic breeding programme, is in place. The present model followed by sheep breeders is highly dependent upon the Government aided Central Sheep and Wool Research Institute (CSWRI) for supply of breeding rams, data collection and health care. Alternate self-sustainable model of CBBP is proposed wherein a breeder's organization leads the way to establish a ram-rearing centre (RRC), teams of experts for ram selection, data collection and market linkage. CSWRI will continue to assist for selection decisions and real-time data entry using a cloud-based "Avimegh" platform. The early selection of 5% male lambs at weaning and rearing them at RRC until final selection at 12-month will provide unbiased selection of rams under CBBP. The surplus rams will be sold by RRC for profit. Several key measures such as micro-finance, co-ordination between stakeholders, market linkage and technical input for data collection and selection have been suggested to make the CBBP self-sustainable.

Sexual health problems and health-seeking behavior of men who have sex with men in Agra City, Uttar Pradesh.

BACKGROUND: Men who have sex with men (MSM) are at high risk of acquiring sexually transmitted illnesses. The gross stigmatization of homosexuality and discrimination has always affected their health-seeking behavior. OBJECTIVES: The study aimed to assess the magnitude of sexual health problems, factors associated, and their health-seeking behavior. METHODS: Descriptive cross-sectional study was conducted in Agra city, Uttar Pradesh during December 2017 and November 2019 among a sample of 52 MSM. The Snowball technique of sampling was used to recruit the eligible subjects. Data were collected by interview and analyzed using MS excel. RESULTS: Overall prevalence of any sexual health problem in past 1 year was 71.2%. Anal/perianal problems (26.9%) and genital/oral vesicles (26.9%) were the most commonly encountered illnesses MSM who had all their sexual encounters with men (completely homosexual), those MSM who used to play both insertive and receptive roles, had 5 or more sexual partners, used condom irregularly had significantly higher chances of having sexual health problems. Most (70.3%) MSM sought treatment for their sexual health problem from an Allopathic doctor; 29.4% took treatment from a government health facility. The majority (94.1%) of them were reportedly satisfied with the health care facility. Most (79.4%) respondents preferred not to disclose their sexual behavior during interaction with their sexual health care provider. CONCLUSION: High prevalence of sexual health problems was found among MSM who engage in high-risk sexual behavior. MSM requires access to STIs screening. Behavior change communication is needed to improve their health-seeking behavior.

Are newer insulin analogues better for people with Type 1 diabetes?

Achieving optimal blood glucose control in Type 1 diabetes is a delicate balance between ensuring tight glycaemic control and achieving this without the expense of hypoglycaemia and weight gain, two major factors impacting quality of life. This is a real challenge for people with Type 1 diabetes and underpins many of the struggles they face in self-managing on a day-to-day basis. The main goals of insulin delivery are to try to simulate the physiology of ß-cell insulin secretion as closely as possible and to overcome the challenges of peripheral insulin administration by achieving rapidity of onset with mealtime insulins and stability of the glucose-lowering effects of long-acting insulins. Since the early days of human insulin use, there have been many developments in insulin formulations that aim to achieve these goals as much as possible, thus contributing to better glycaemic control whilst minimizing hypoglycaemia. In the present review we discuss the currently available insulin analogues and the challenges of achieving glucose control using current analogues in those on multiple daily injections, and appraise the evidence base for newer-generation insulin analogues, such as insulin degludec, glargine U300, faster-acting insulin aspart and BioChaperone lispro. We also highlight new insulins in development and unmet needs in people with Type 1 diabetes.

Fulminant amebic colitis: An unusual postoperative complication of intraabdominal malignancy.

Amebiasis caused by protozoa Entamoeba histolytica (EH) is the third leading parasitic cause of human mortality. Although amebiasis is endemic in India, only about 10% of the infected individuals manifest disease. Clinical spectrum of amebiasis ranges from asymptomatic colonization to amebic colitis to hemorrhagic and fulminant colitis. Factors causing an invasive infection are not completely understood. Pathogen virulence, host immunity, and ability of the pathogen to evade host immune response play vital role in determining the disease course. Host factors such as immunocompromised states may make an individual susceptible to develop symptomatic infection. Malignancies usually result in chronic debilitation which may make the individual prone to develop invasive amebiasis with rapid progression. We report two cases of invasive amebiasis which developed a fulminant course in the immediate postoperative period after abdominal surgeries for visceral malignancies.

Nitrogen partitioning and remobilization in relation to leaf senescence, grain yield and protein concentration in Indian wheat cultivars.

Nitrogen (N) fertilizer represents a significant cost for the grower and may also have environmental impacts through nitrate leaching and N2O (a greenhouse gas) emissions associated with denitrification. The objectives of this study were to quantify the genetic variability in N partitioning and N remobilization in Indian spring wheat cultivars and identify traits for improved grain yield and grain protein content for application in breeding N-efficient cultivars. Twenty-eight bread wheat cultivars and two durum wheat cultivars were tested in field experiments in two years in Maharashtra, India. Growth analysis was conducted at anthesis and harvest to assess above-ground dry matter (DM) and dry matter and N partitioning. Flag-leaf photosynthesis rate (A max ), flag-leaf senescence rate and canopy normalized difference vegetation index (NDVI) were also assessed. Significant N × genotype level interaction was observed for grain yield and N-use efficiency. There was a positive linear association between post-anthesis flag-leaf A max and grain yield amongst the 30 genotypes under high N (HN) conditions. Flag-leaf A max was positively associated with N uptake at anthesis (AGNA). Under both HN and low N (LN) conditions, higher N uptake at anthesis was associated with delayed onset of flag-leaf senescence and higher grain yield. Under N limitation, there was a genetic negative correlation between grain yield and grain protein concentration. Deviation from this negative relationship (grain protein deviation or GPD) was related to genotypic differences in post-anthesis N uptake. It is concluded that N uptake at anthesis was an important determinant of flag-leaf photosynthesis rate and grain yield under high N conditions; while post-anthesis N uptake was an important determinant of GPD of wheat grown under low to moderate N conditions in India.

The breeding structure for the small ruminant resources in India.

Intense selection for a few desired traits has resulted in reduction of the effective population size (Ne) in most of the plant and livestock populations across the world. The objective of the research was to assess the impact of Ne on the genetic architecture of the population in a simulated data with variable Ne for general population under selection. Along with this, the estimate of Ne and its ratio to adult breeding population (NB) in the census data of small ruminants of India were also investigated. Results indicated that the average inbreeding ([Formula: see text]) decreases with increase in Ne; similarly, increase in [Formula: see text] per generation was highest in population with lowest Ne. Correlation of estimated breeding value (EBV) with true breeding value (TBV) was not much affected with effective population size. An effective number of chromosome segments (Me) in the populations under selection were significantly affected by magnitude of Ne, with linear positive relation between Ne and Me. Results on livestock census data revealed that all the sheep and goat breeds have sufficiently large Ne based on derived and actual census data. The median for ratio of effective population size to adult census size in sheep breeds was 0.120 and for goat breeds was 0.131. Karnah and Poonchi sheep shares the status of endangered breeds due to a smaller number of breeding female population and hence need attention for conservation. The Ne was large in sheep and goat due to less selection pressure as a result of low coverage of breed improvement programs, availability of large number of breeding males, and absence of artificial insemination (AI) in the field flocks. The estimates of Ne and its ratio to the adult census size (NB) excluded several factors such as fluctuating population size and overlapping generations. Study revealed introspection from most of the industrial breeding programs on the issue of Ne for populations under selection. Similarly, in small ruminants, large Ne indicates huge genetic diversity and scope of improvement in the productivity in near future.

Of "Cotton Balls" and "Owl's eyes".

Report of a 3-month old girl child who died due to multi-systemic infection of cytomegalovirus (CMV) involving the lungs, liver and kidneys along with pneumocystis jiroveci pneumonia (PJP). The mother of the child tested positive for CMV IgG and HIV with a very low CD4 count (160/ µl). Co-infection of cytomegalovirus and pneumocystis jiroveci always occurs in the setting of immunocompromise. Congenital CMV infection is transmitted through the placenta, especially during the first trimester and causes severe multi-systemic disease whereas perinatal infection is acquired during childbirth/ breastfeeding where the babies have maternal protective antibodies leading to much milder or asymptomatic infection. PJP is more common in infancy and presents as hypoxic pneumonia. CMV causes cyto-nucleomegaly and classic "owl's eye" inclusions on histology while PJP presents with characteristic fluffy "cotton ball" alveolar exudates.

Permanent neonatal diabetes: combining sulfonylureas with insulin may be an effective treatment.

BACKGROUND: Permanent neonatal diabetes caused by mutations in the KCNJ11 gene may be managed with high-dose sulfonylureas. Complete transfer to sulfonylureas is not successful in all cases and can result in insulin monotherapy. In such cases, the outcomes of combining sulfonylureas with insulin have not been fully explored. We present the case of a woman with diabetes due to a KCNJ11 mutation, in whom combination therapy led to clinically meaningful improvements. CASE: A 22-year-old woman was found to have a KCNJ11 mutation (G334V) following diagnosis with diabetes at 3 weeks. She was treated with insulin-pump therapy, had hypoglycaemia unawareness and suboptimal glycaemic control. We assessed the in vitro response of the mutant channel to tolbutamide in Xenopus oocytes and undertook sulfonylurea dose-titration with C-peptide assessment and continuous glucose monitoring. In vitro studies predicted the G334V mutation would be sensitive to sulfonylurea therapy [91 ± 2% block (n = 6) with 0.5 mM tolbutamide]. C-peptide increased following a glibenclamide test dose (from 5 to 410 pmol/l). Glibenclamide dose-titration was undertaken: a lower glibenclamide dose did not reduce blood glucose levels, but at 1.2 mg/kg/day insulin delivery was reduced to 0.1 units/h. However, when insulin was stopped, hyperglycaemia ensued. Glibenclamide was further increased (2 mg/kg/day), but once-daily long-acting insulin was still required to maintain glycaemia. This resulted in improved HbA1c of 52 mmol/mol (6.9%), restoration of hypoglycaemia awareness and reduced glycaemic variability. CONCLUSION: In people with KCNJ11 mutations causing permanent neonatal diabetes, and where complete transfer is not possible, consideration should be given to dual insulin and sulfonylurea therapy. This article is protected by copyright. All rights reserved.

Detection of prostate specific antigen (PSA) in human saliva using an ultra-sensitive nanocomposite of graphene nanoplatelets with diblock-co-polymers and Au electrodes.

Prostate-specific antigen (PSA) is a commonly used biomarker for the detection of prostate cancer (PCa) and there are numerous data available for its invasive detection in the serum and whole blood. In this work, an electrochemical sensing method was devised to detect traces of PSA in human saliva using a hybrid nanocomposite of graphene nanoplatelets with diblock co-polymers and Au electrodes (GRP-PS67-b-PAA27-Au). The pure graphitic composition on filter paper provides significantly high electrical and thermal conductivity while PS67-b-PAA27 makes an amphiphilic bridge between GRP units. The sensor utilizes the binding of an anti-PSA antibody with an antigen-PSA to act as a resistor in a circuit providing an impedance change that in turn allows for the detection and quantification of PSA in saliva samples. A miniaturized electrical impedance analyzer was interfaced with a sensor chip and the data were recorded in real-time using a Bluetooth-enabled module. This fully integrated and optimized sensing device exhibited a wide PSA range of detection from 0.1 pg mL-1 to 100 ng mL-1 (R2 = 0.963) with a lower limit of detection of 40 fg mL-1. The performance of the biosensor chip was validated with an enzyme-linked immunosorbent assay technique with a regression coefficient as high as 0.940. The advantages of the newly developed saliva-PSA electrical biosensor over previously reported serum-PSA electrochemical biosensors include a faster response time (3-5 min) to achieve a stable electrical signal for PSA detection, high selectivity, improved sensitivity, no additional requirement of a redox electrolyte for electron exchange and excellent shelf life. The presented sensor is aimed for clinical commercialization to detect PSA in human saliva.

Genetic variation in N-use efficiency and associated traits in Indian wheat cultivars.

Nitrogen (N) fertilizer represents a significant cost for the grower and may also have environmental impacts through nitrate leaching and N2O (a greenhouse gas) emissions associated with denitrification. The objectives of this study were to quantify the genetic variability in N-use efficiency (NUE) in Indian spring wheat cultivars and identify traits for improved NUE for application in breeding. Twenty eight bread wheat cultivars and two durum wheat cultivars were tested in field experiments in two years in Maharashtra, India. Detailed growth analysis was conducted at anthesis and harvest including dry matter (DM) and N partitioning. Senescence of the flag leaf was assessed from a visual score every 3-4 days from anthesis to complete flag-leaf senescence and fitted against thermal time to estimate the onset and end of post-anthesis senescence. Grain yield (GY) was reduced under low N (LN) by an average of 1.46 t ha-1 (-28%). Significant N × genotype level interaction was observed for grain yield and NUE. Above-ground N uptake at harvest was reduced from 162 kg N ha-1 under high N (HN) to 85 kg N ha-1 under low N (LN) conditions, while N-utilization efficiency (grain DM yield per unit crop N uptake at harvest; NUtE) increased from 32.7 to 44.6 kg DM kg-1 N. Genetic variation in GY under LN related mainly to variation in N uptake at harvest rather than NUtE; and the N × genotype effect for GY was mainly explained by the interaction for N uptake at harvest. Averaging across years, the linear regression of onset of flag-leaf senescence on GY amongst cultivars was significant under both HN (R2 0.16. p < 0.05) and LN (R2 0.21, p < 0.05) conditions. Onset of flag-leaf senescence was positively associated with N uptake at anthesis under HN (R2 0.34, p < 0.001) and LN (R2 0.22, p < 0.01) conditions. Flag-leaf senescence timing was not associated with post-anthesis N uptake. It is concluded that increased N accumulation at anthesis was correlated with flag-leaf senescence timing and that N accumulation at anthesis is an important trait for enhancing grain yield and NUE of wheat grown under low to moderate N supply in India.

Steering and control of miniaturized untethered soft magnetic grippers with haptic assistance.

Untethered miniature robotics have recently shown promising results in several scenarios at the microscale, such as targeted drug delivery, microassembly, and biopsy procedures. However, the vast majority of these small-scale robots have very limited manipulation capabilities, and none of the steering systems currently available enable humans to intuitively and effectively control dexterous miniaturized robots in a remote environment. In this paper, we present an innovative micro teleoperation system with haptic assistance for the intuitive steering and control of miniaturized self-folding soft magnetic grippers in 2-D space. The soft grippers can be wirelessly positioned using weak magnetic fields and opened/closed by changing their temperature. An image-guided algorithm tracks the position of the controlled miniaturized gripper in the remote environment. A haptic interface provides the human operator with compelling haptic sensations about the interaction between the gripper and the environment, as well as enables the operator to intuitively control the target position and grasping configuration of the gripper. Finally, magnetic and thermal control systems regulate the position and grasping configuration of the gripper. The viability of the proposed approach is demonstrated through two experiments involving 26 human subjects. Providing haptic stimuli elicited statistically significant improvements in the performance of the considered navigation and micromanipulation tasks. Note to Practitioners-The ability to accurately and intuitively control the motion of miniaturized grippers in remote environments can open new exciting possibilities in the fields of minimally-invasive surgery, micromanipulation, biopsy, and drug delivery. This paper presents a micro teleoperation system with haptic assistance through which a clinician can easily control the motion and open/close capability of miniaturized wireless soft grippers. It introduces the underlying autonomous magnetic and thermal control systems, their interconnection with the master haptic interface, and an extensive evaluation in two real-world scenarios: following of a predetermined trajectory, and pick-and-place of a microscopic object.