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This work investigates controllability issues under the leader–follower framework of consensus problem on multi-agent networks where its agents exhibit the heterogeneous dynamics involving first-, second-, and third-order integrator agents on a continuous time-scale. The communication topology is directed, time-invariant, and the reliability of all interactions are unity. We employ two kinds of consensus protocols that are linear and distributed. The necessary and sufficient criteria for the controllability of followers’ dynamics through the selected leaders are obtained in terms of matrix-rank conditions. We also obtain some necessary conditions of controllability involving eigenvectors of system matrices. It is verified that, if either of the first-, second-, or third-order integrator agents are absent, then the controllability of the network becomes equivalent to the controllability of the communication topology just like those of the networks with homogeneous dynamic agents. Obtained results are verified with illustrative examples.

Temperature trends over the high-altitude mountains depict an increase with elevation during recent years. These stratified warming trends observed over the Himalayan-Tibetan (HT) regions are higher than the mean warming trends observed over low-elevation regions of South and East Asia, which is attributed to several factors including snow albedo feedback, clouds and water vapor feedback. In this study, we demonstrate the effects of deposition of absorbing aerosols like black carbon and dust on snow albedo and its implications for elevation-dependent warming (EDW). Though the aerosol concentration decreases with elevation, warming due to aerosol-induced snow darkening increases with elevation. Further, surface cooling due to the direct radiative effects (DRE) of aerosols is found to decrease with elevation, which also favors higher warming at high altitudes. The effects of both the deposition of absorbing aerosols on snow albedo and the surface cooling due to the DRE of atmospheric aerosols could strengthen EDW. This study clearly shows the potential of albedo feedback due to aerosol-cryosphere interaction as one of the physical mechanisms contributing to the observed EDW over the HT region.

The recent trend in global mean temperature is expected to increase the frequency, duration, and intensity of heat waves and heat stress all around the world, especially over the Indian subcontinent. To investigate the plausible mechanisms and implications of meteorological feedback of aerosol forcing on heat stress over South Asia, simulations using a regional climate model (RegCM4) coupled with aerosols were carried out from 2015 to 2019. Generally, extreme heat days are observed mainly over the central and western Indo-Gangetic plains (IGPs) during May. The two heat-humidity indices, wet-bulb temperature (WBT) and heat index (HI), showed moderate effects due to aerosol forcing despite the high aerosol loading during the pre-monsoon. The inclusion of aerosols leads to surface cooling (a reduction in maximum surface temperature), with the highest impact over western India (WI) and the IGP. However, this surface cooling due to aerosols is compensated by an increase in near-surface relative humidity (RH), leading to an increase in WBT and HI. This compensating effect of RH on WBT and HI is greater in WI than that in eastern India. Regional heterogeneity in aerosol-induced changes in heat stress has a strong dependence on land-atmosphere interactions. This study clearly shows that aerosol-induced changes in RH play a decisive role in the assessment of heat stress, which answers the link between the prevalence of high heat stress conditions despite high aerosol loading (surface cooling) over the Indian region.

Natural language processing (NLP) developments have made it possible for robots to read and analyze human language with astounding precision, revolutionizing the field of text understanding. An overview of current advancements in NLP approaches and their effects on text comprehension are provided in this abstract. It examines significant developments in fields including named entity identification, sentiment analysis, semantic analysis, and question answering, highlighting the difficulties encountered and creative solutions put forth. To sum up, recent developments in natural language processing have raised the bar for text comprehension. Deep learning models and extensive pre-training have changed methods including semantic analysis, sentiment analysis, named entity identification, and question answering. These developments have produced text comprehension systems that are increasingly precise and complex. However, issues with prejudice, coreference resolution, and contextual comprehension still need to be resolved. The future of NLP for text understanding has considerable potential with continuing study and innovation, opening the door for increasingly sophisticated applications in numerous sectors.

Saravanakumari Vijayakumar,1 Stalin Viswanathan,2 Rajeswari Aghoram3 1Pathology, Sri Lakshmi Narayana Institute of Medical Sciences, Pondicherry 605502, India; 2General Medicine, Jawaharlal Institute of Postgraduate Medical Education and Research, Pondicherry 605006, India; 3Department of Neurology, Jawaharlal Institute of Postgraduate Medical Education and Research, Pondicherry 605006, IndiaCorrespondence: Rajeswari AghoramDepartment of Neurology, Jawaharlal Institute of Postgraduate Medical Education and Research, D. Nagar, Pondicherry 605006, IndiaTel +91 413 229 7285Email rajeswari.a@gmail.comAbstract: Idiopathic CD4 lymphocytopenia is a condition characterized by low CD4 counts. It is rare and most of the information about this illness comes from case reports. Presentation is usually in the 4th decade of life with opportunistic infections, autoimmune disease or neoplasia. The pathophysiology of this condition is not well understood. Management revolves around treatment of the presenting condition and close follow-up of these patients. This review presents a narrative summary of the current literature on idiopathic CD4 lymphocytopenia.Keywords: CD4 T cell lymphocytopenia, opportunistic infections, neoplasia, autoimmune disease

A field experiment was conducted in 2015–16 and 2016–17 to estimate the energy budget of aerobic rice (Oriza sativa L.)-wheat (Triticum aestivum L.) cropping system (RWCS) as influenced by K fertilization. Results revealed that in aerobic RWCS the non-renewable energy and renewable energy shares 86% and 14% of the total input energy use respectively. Split application of recommended dose of K (RDK=60 kg K2O/ha) in both rice and wheat, at 50:50 or 75:25 ratio increased the system productivity by 8.2% over applying entire dose as basal (B). Among the treatments, T12 (150% RDK as basal) recorded the highest energy input (37481.5 MJ/ha), whereas T1 (control) recorded the lowest (35474.5 MJ/ha). Treatments T11 [75% RDK as basal + 25% at panicle initiation (PI) or ear initiation (EI)+ 2 foliar spray of 2.5% KNO3] recorded the highest output energy (340 ×103 MJ/ha) which remained at par with T4 [50% RDK as basal + 50% at panicle initiation (PI) or ear initiation (EI)], whereas the lowest was recorded in control (275.9 ×103 MJ/ha). Two split application of 60 kg K2O/ha at 50:50 ratio increased the system energy output by 5.5% and 13.5% over T2 (100% RDK as basal) and T3 (50% RDK as basal) respectively. Similarly, split application of potassium under T4 treatments increased the system energy use efficiency, energy productivity and energy profitability by 17.9%, 25% and 20.5% respectively over control. Thus in aerobic RWCS, 4R (right time, right dose, right method, right form) stewardship based K application ensure efficient utilization of input energy and maximize the production of biological energy.

The effect of potassium (K) application based on 4R stewardship (right rate, time, method, and source) on growth, yield attributes and yields of dry direct seeded basmati rice (Oryza sativa L.) was evaluated during rainy (kharif) season of 2015 and 2016 at IARI, New Delhi. Application of recommended dose of K (60 kg/ha), half as basal and remaining half at panicle initiation (PI) stage increased the grain (5.4 t/ha) and straw yields (7.65 t/ha) by 10 and 4% respectively, over applying the full dose as basal. A strong, positive and significant correlation was observed between yield attributes [panicle weight (r2=0.79), panicle length (r2=0.83), fertility % (r2=0.84)] and yield of dry direct seeded basmati rice. Similarly, positive and significant correlation was observed between leaf area index at 60 DAS (r2=0.73) & 90 DAS (r2=0.91) and dry matter production. The two foliar sprays of 2.5% potassium nitrate (1st at active tillering, and 2nd at panicle initiation) increased fertility (83.5%) and grain yield (4.3 t/ha) by 6% and 8% respectively, over control. However, the combined application of foliar sprays and two split application of recommended dose of K showed non-significant effect on growth, yield and yield attributes. Thus, to obtain higher yield in dry direct seeded basmati rice, application of 60 kg/ha, half as basal and remaining half at panicle initiation (PI) is recommended.

Regional heterogeneity in direct and snow albedo forcing of aerosols over the Himalayan cryosphere was investigated using a regional climate model coupled with the community land model having snow, ice and aerosol radiation module. Deposition of absorbing aerosols like dust (natural) and black carbon (BC) (anthropogenic) decreases the snow albedo (snow darkening) over the Himalayas. Western Himalayas experiences a large reduction in the snow albedo (0.037) despite having lower BC mass concentration compared to central (0.014) and eastern (0.005) Himalayas. The contribution of BC and dust to the snow albedo reduction is comparable over the western and eastern Himalayas. The inclusion of aerosol-induced snow darkening in to the model reduces its bias with respect to the satellite derived surface albedo by 59%, 53% and 35% over western, central and eastern Himalayas respectively during the spring season. Since surface albedo decides the sign and magnitude of aerosol direct radiative forcing, aerosol induced snow darkening significantly affects the direct radiative effects of aerosols. Hence, the aerosol-induced decrease in snow albedo causes an early reversal in the sign of aerosol direct radiative forcing at the top of the atmosphere from warming to cooling over the western and central Himalayas, which can have implications in the radiation balance and water security over the region.

Introduction: Infective keratitis is a potentially vision threatening condition caused by various microbial etiology. Due to high virulence and rapid progression of many etiological agents, any corneal inflammation should be considered a potential threat to vision, requiring immediate evaluation and treatment. Evaluation of epidemiological and microbiological profile of infective keratitis of a region can significantly contribute towards appropriate management of this ophthalmic emergency. Aim: To study the bacterial and fungal etiological agents and the epidemiological factors associated with infective keratitis in patients attending the Ophthalmology Department of Government Medical College, Thrissur, Kerala, India. Settings and Study Design: In this cross-sectional study, a total of 135 corneal scrapings were evaluated from patients presenting with corneal ulcers from December 2012 to May 2014. Materials and Methods: Scrapings were subjected to Gram staining, KOH wet mount and culture for bacterial and fungal pathogens. Isolates were identified by conventional methods and their antibiotic susceptibility pattern was established. Statistical Analysis: The results were analysed by mean, Chisquare test and Fisher’s exact test. Results: Corneal trauma was the main risk factor associated with infective keratitis (59.3%) and vegetative matter was the most common trauma type observed (36.3%). Culture was positive in 35.56% of cases, of which 18.52% were bacterial and 17.04% were fungal. Gram positive cocci were the predominant isolates (64%). Staphylococcus epidermidis was the most common bacterial isolate (32%), followed by Streptococcus pneumoniae and Pseudomonas aeruginosa (16% each). Fusarium species was the most common fungal isolate (39.13%), followed by Curvularia species and Aspergillus species (13.04%). Unidentified dematiaceous fungi accounted for 17.39%. Sensitivity of Gram stain in bacterial and fungal detection was 56% and 39%, while specificity was 95% and 96% respectively. Sensitivity and specificity of KOH wet mount examination in the detection of fungal elements was observed as 82% and 91% respectively. Conclusion: Our study observed corneal injury as the main risk factor associated with infective keratitis. Males were more affected than females. Staphylococcus epidermidis and Fusarium species were the commonest bacterial and fungal isolates respectively. Geographical variation persists in microbial etiology of infective keratitis

Background: Contrast induced nephropathy (CIN) is associated with significant morbidity and mortality after percutaneous coronary intervention (PCI). The aim of this study is to evaluate the collective probability of CIN in Indian population by developing a scoring system of several identified risk factors in patients undergoing PCI. Methods: This is a prospective single center study of 1200 consecutive patients who underwent PCI from 2008 to 2011. Patients were randomized in 3:1 ratio into development (n = 900) and validation (n = 300) groups. CIN was defined as an increase of ≥25% and/or ≥0.5 mg/dl in serum creatinine at 48 hours after PCI when compared to baseline value. Seven independent predictors of CIN were identified using logistic regression analysis - amount of contrast, diabetes with microangiopathy, hypotension, peripheral vascular disease, albuminuria, glomerular filtration rate (GFR) and anemia. A formula was then developed to identify the probability of CIN using the logistic regression equation. Results: The mean (±SD) age was 57.3 (±10.2) years. 83.6% were males. The total incidence of CIN was 9.7% in the development group. The total risk of renal replacement therapy in the study group is 1.1%. Mortality is 0.5%. The risk scoring model correlated well in the validation group (incidence of CIN was 8.7%, sensitivity 92.3%, specificity 82.1%, c statistic 0.95). Conclusion: A simple risk scoring equation can be employed to predict the probability of CIN following PCI, applying it to each individual. More vigilant preventive measures can be applied to the high risk candidates.

Formation of ultrafine particles and their subsequent growth have been examined during new particle formation (NPF) events in two contrasting environments under varying ambient conditions, one for a tropical semi-urban coastal station, Trivandrum, and the other for a high-altitude free-tropospheric Himalayan location, Hanle. At Trivandrum, NPF bursts took place in the late evening/night hours, whereas at Hanle the burst was a daytime event. During the nucleation period, the total number concentration reached levels as high as ~ 15 900 cm−3 at Trivandrum, whereas at Hanle, the total number concentration was ~ 2700 cm−3, indicating the abundant availability of precursors at Trivandrum and the pristine nature of Hanle. A sharp decrease was associated with NPF for the geometric mean diameter of the size distribution, and a large increase in the concentration of the particles in the nucleation regime (Dp < 25 nm). Once formed, these (secondary) aerosols grew from nucleation (diameter Dp < 25 nm) to Aitken (25 ≤ Dp ≤ 100 nm) regime and beyond, to the accumulation size regimes (100 ≤ Dp ≤ 1000 nm), with varying growth rates (GR) for the different size regimes at both the locations. A more rapid growth ~ 50 nm h−1 was observed at Trivandrum, in contrast to Hanle where the growth rate ranged from 0.1 to 20 nm h−1 for the transformation from the nucleation to accumulation – a size regime that can potentially act as cloud condensation nuclei (CCN). The faster coagulation led to lifetimes of < 1 h for nucleation mode particles.

Absorbing aerosols such as black carbon (BC) or dust over high-altitude Himalayan regions have potential implications on the regional climate and hydrological cycle over South Asia. Making use of extensive measurements of atmospheric BC from several Himalayan stations, an assessment of radiative forcing due to direct and snow-albedo darkening is examined. Generally, BC concentration in the atmosphere peaks during pre-monsoon season over the Himalayas and the climatological mean of atmospheric BC over Hanle (western Himalayas, 4.5 km msl) and Nepal Climate Observatory-Pyramid (central Himalayas, 5 km msl) are 106±27 ng m−3 and 190±95 ng m−3, respectively. Based on the optical and physical properties of composite aerosols measured at Hanle, clear sky direct radiative forcing (DRF) at the top of the atmosphere is estimated as 1.69 W m−2 over snow surface and −1.54 W m−2 over sandy surface during pre-monsoon season. The estimated amount of BC in the snow varied from 117 to 1.7 µg kg−1 for wide range of dry deposition velocities (0.01–0.054 cm s−1) of BC, snow depth (2–10 cm) and snow densities (195–512 kg m−3). Using a size-resolved wet scavenging parametrisation, the amount of BC on snow due to wet scavenging is estimated as 29 µg kg−1 for an accumulated snow depth of 27 cm. For the range of 10–200 µg kg−1 of BC in snow, the diurnally averaged forcing due to snow darkening has been found to vary from 0.87 to 10.2 W m−2 for fresh snow and from 2.6 to 28.1 W m−2 for the aged snow, which is significantly higher than the DRF. The direct and surface albedo radiative forcing could lead to significant warming over the Himalayas during pre-monsoon.

A numerical study is presented on the effects of chemical reaction and magnetic field on the unsteady free convection flow, heat and mass transfer characteristics in a viscous, incompressible and electrically conducting fluid past an exponentially accelerated vertical plate by taking into account the heat due to viscous dissipation. The problem is governed by coupled non-linear partial differential equations. The dimensionless equations of the problem have been solved numerically by the implicit finite difference method of Crank - Nicolson’s type. The effects of governing parameters on the flow variables are discussed quantitatively with the aid of graphs for the flow field, temperature field, concentration field, skin-friction, Nusselt number and Sherwood number. It is found that under the influence of chemical reaction, the flow velocity as well as concentration distributions reduce, while the viscous dissipation parameter leads to increase the temperature.

Background/Aims: To assess the factors causing delay in attaining DTB time of 90 min occurred in 23.5%. Mean door to ECG – 6.5 min (SD = 2.7), mean time for the decision of PCI – 7.5 min (SD = 10.5), mean time taken for the patient's consent – 19.6 min (SD = 17.6), for STEMI team activation – 6.7 min (SD = 7.6), average time for financial process – 39.2 min (SD = 22.9). Average time for sheath to balloon – 5.2 min (SD = 1.7). Hospital related delay occurred in 5%, patient related delay in 80%, both together in 15%. 89.5% of patient related delay was due to delay in giving consent and financial reasons. There was no statistically significant delay for patients presented at morning or night and during the weekdays or weekend. Total mortality was 4.7%. Mortality among 90 min was 10% (‘p’ = 0.2). Conclusions: With effective hospital strategies, the DTB time of 90 min can be achieved in majority of patients. The chief delay in DTB time in this study was due to a delay in obtaining consent and financial reasons.

This investigation is undertaken to study the hydromagnetic flow of a viscous incompressible fluid past an oscillating vertical plate embedded in a porous medium with radiation, viscous dissipation and variable heat and mass diffusion. Governing equations are solved by unconditionally stable explicit finite difference method of DuFort - Frankel’s type for concentration, temperature, vertical velocity field and skin - friction and they are presented graphically for different values of physical parameters involved. It is observed that plate oscillation, variable mass diffusion, radiation, viscous dissipation and porous medium affect the flow pattern significantly.