Hindcasting and Validation of Mumbai Oil Spills using GNOME

Oil spill trajectory forecasting became mandatory for providing advisory services to the regulatory authorities during the event of oil spill, for planning their remediation and clean up measures. The present study describes a method to simulate the trajectory of the spilled oil using GNOME and validating it using available Radar data. The trajectory forecasting of two oil spill events, happened in mumbai high region, during 2010- 2011 has been executed in hindcast mode using General NOAA Operational Modeling Environment. The forcing parameters such as, forecasted European Center of Medium Range Weather Forecast winds and Regional Ocean Modeling system currents were used for the execution. The likely areas which are to be affected are found from the prediction. The trajectory obtained from GNOME is compared with oil spill signatures obtained from the radar data of a particular time step. The observed oil slicks were found within the average distance of 3.73 km and 4.16 km from the prediction for MSC chitra spill and Mumbai uran trunk pipeline spill respectively. This trajectory model can be used for making the contingency plans, conducting the mock drills and during oil spill response and preparedness operation

Pulmonary vasospasm in systemic sclerosis: noninvasive techniques for detection

In a subgroup of patients with systemic sclerosis (SSc), vasospasm affecting the pulmonary circulation may contribute to worsening respiratory symptoms, including dyspnea. Noninvasive assessment of pulmonary blood flow (PBF), utilizing inert-gas rebreathing (IGR) and dual-energy computed-tomography pulmonary angiography (DE-CTPA), may be useful for identifying pulmonary vasospasm. Thirty-one participants (22 SSc patients and 9 healthy volunteers) underwent PBF assessment with IGR and DE-CTPA at baseline and after provocation with a cold-air inhalation challenge (CACh). Before the study investigations, participants were assigned to subgroups: group A included SSc patients who reported increased breathlessness after exposure to cold air (n = 11), group B included SSc patients without cold-air sensitivity (n = 11), and group C patients included the healthy volunteers. Median change in PBF from baseline was compared between groups A, B, and C after CACh. Compared with groups B and C, in group A there was a significant decline in median PBF from baseline at 10 minutes (−10%; range: −52.2% to 4.0%; P < 0.01), 20 minutes (−17.4%; −27.9% to 0.0%; P < 0.01), and 30 minutes (−8.5%; −34.4% to 2.0%; P < 0.01) after CACh. There was no significant difference in median PBF change between groups B or C at any time point and no change in pulmonary perfusion on DE-CTPA. Reduction in pulmonary blood flow following CACh suggests that pulmonary vasospasm may be present in a subgroup of patients with SSc and may contribute to worsening dyspnea on exposure to cold

Evaluation of oil spill trajectory model with the observed SVP drifter track

Indian National Centre for Ocean Information Services (INCOIS) collaborated with Indian Coast Guard(ICG) and conducted Surface Velocity Program (SVP) drifter experiment at Mumbai High region for evaluating the operational oil spill trajectory model. INCOIS adopted General National Oceanic and Atmospheric Administration(NOAA) Operational Modelling Environment(GNOME) from NOAA and customised it in diagnostic mode for Indian ocean. GNOME was operationalised during May 2014. The objective of this experiment is to compare the drift pattern obtained from an oil spill trajectory model with the observed drifter track. SVP drifter was procured from M/s. Pacific Gyre, USA. It gives the Lagrangian trajectory path over the ocean. It was deployed by officials of Indian Coast Guard at Mumbai High region on 20 November 2016,12.45 hrs at 72.2295º E, 18.91035º N off Mumbai. It gave its drifted path along the west coast of India for ten days, before it beached near Diu on 3 December 2016.This observed track was considered for comparing the simulated positions obtained from GNOME when forced with currents of different ocean general circulation models. The results show that the positions of the drifter obtained, while forced with analysed currents of GODAS -MOM4p1 (GM4p1) and Hybrid Co-ordinate Ocean Model (HYCOM) are found to be in better agreement with the actual position of the drifter

Opportunity cost determines free-operant action initiation latency and predicts apathy

Background Apathy, a disabling and poorly understood neuropsychiatric symptom, is characterised by impaired self-initiated behaviour. It has been hypothesised that the opportunity cost of time (OCT) may be a key computational variable linking self-initiated behaviour with motivational status. OCT represents the amount of reward which is foregone per second if no action is taken. Using a novel behavioural task and computational modelling, we investigated the relationship between OCT, self-initiation and apathy. We predicted that higher OCT would engender shorter action latencies, and that individuals with greater sensitivity to OCT would have higher behavioural apathy. Methods We modulated the OCT in a novel task called the 'Fisherman Game', Participants freely chose when to self-initiate actions to either collect rewards, or on occasion, to complete non-rewarding actions. We measured the relationship between action latencies, OCT and apathy for each participant across two independent non-clinical studies, one under laboratory conditions (n = 21) and one online (n = 90). 'Average-reward' reinforcement learning was used to model our data. We replicated our findings across both studies. Results We show that the latency of self-initiation is driven by changes in the OCT. Furthermore, we demonstrate, for the first time, that participants with higher apathy showed greater sensitivity to changes in OCT in younger adults. Our model shows that apathetic individuals experienced greatest change in subjective OCT during our task as a consequence of being more sensitive to rewards. Conclusions Our results suggest that OCT is an important variable for determining free-operant action initiation and understanding apathy

Imbalanced basal ganglia connectivity is associated with motor deficits and apathy in Huntington's disease

The gating of movement depends on activity within the cortico-striato-thalamic loops. Within these loops, emerging from the cells of the striatum, run two opponent pathways-the direct and indirect basal ganglia pathway. Both are complex and polysynaptic but the overall effect of activity within these pathways is thought to encourage and inhibit movement respectively. In Huntington's disease (HD), the preferential early loss of striatal neurons forming the indirect pathway is thought to lead to disinhibition giving rise to the characteristic motor features of the condition. But early HD is also associated with apathy, a loss of motivation and failure to engage in goal-directed movement. We hypothesised that in HD, motor signs and apathy may be selectively correlated with indirect and direct pathway dysfunction respectively. We used spectral dynamic casual modelling of resting state fMRI data to model effective connectivity in a model of these cortico-striatal pathways. We tested both of these hypotheses in vivo for the first time in a large cohort of patients with prodromal HD. Using an advanced approach at the group level by combining Parametric Empirical Bayes and Bayesian Model Reduction procedure to generate large number of competing models and compare them by using Bayesian model comparison. With this automated Bayesian approach, associations between clinical measures and connectivity parameters emerge de novo from the data. We found very strong evidence (posterior probability > 0.99) to support both of our hypotheses. Firstly, more severe motor signs in HD were associated with altered connectivity in the indirect pathway components of our model and, by comparison, loss of goal-direct behaviour or apathy, was associated with changes in the direct pathway component. The empirical evidence we provide here is demonstrates that imbalanced basal ganglia connectivity may play an important role in the pathogenesis of some of commonest and disabling features of HD and may have important implications for therapeutics

Determining Conductivity and Thickness of Continuously Varying Layers on Metals Using Eddy Currents

Modifications to metal surfaces are important for many products; they can improve the interaction of the product with its environment, while retaining the structural properties of the bulk metal. Surface modifications provide properties such as good electrical contact as well as resistance to wear, corrosion and high temperatures. Consequently, it is desirable to develop nondestructive methods for characterizing near-surface properties, such as the electrical conductivity and magnetic permeability. In this paper we present an eddy current method to determine the structure of continuously changing surface layers.</p

Prosthetic Management of Oroantral Communication: A Case Report

Oro-Antral Communication (OAC) is an abnormal communication between the maxillary sinus and the oral cavity. It may be the result of different pathological processes and often occurs following an extraction. This article presents a case of closure of OAC followed by a failed palatal flap. A maxillary obturator was designed and fabricated in heat polymerized acrylic resin. The treatment should always be individualized and planned to avoid failures and promote fast healing

A practical guide to automating fluorine-18 PET radiochemistry using commercially available cassette-based platforms

The automation of positron emission tomography (PET) radiochemistry using cassette-based automated radiosynthesis platforms is an essential component of clinical translation for the vast majority of 18F-based radiopharmaceuticals. The technology is widely adopted by good manufacturing practice (GMP) compliant radiopharmaceutical production facilities and research institutions developing novel tracers for clinical studies. Despite automation being fundamental to clinical translation, educational resources which introduce this branch of radiochemistry to the uninitiated are limited. Publications featuring automation assume previous experience of using these platforms and therefore, the detail they provide may not be sufficient for a novice user. In this Tutorial Account, we aim to bridge this knowledge gap and provide a resource for efficient automation for radiochemists across all levels of experience

Manipulating infrared photons using plasmons in transparent graphene superlattices

Superlattices are artificial periodic nanostructures which can control the flow of electrons. Their operation typically relies on the periodic modulation of the electric potential in the direction of electron wave propagation. Here we demonstrate transparent graphene superlattices which can manipulate infrared photons utilizing the collective oscillations of carriers, i.e., plasmons of the ensemble of multiple graphene layers. The superlattice is formed by depositing alternating wafer-scale graphene sheets and thin insulating layers, followed by patterning them all together into 3-dimensional photonic-crystal-like structures. We demonstrate experimentally that the collective oscillation of Dirac fermions in such graphene superlattices is unambiguously nonclassical: compared to doping single layer graphene, distributing carriers into multiple graphene layers strongly enhances the plasmonic resonance frequency and magnitude, which is fundamentally different from that in a conventional semiconductor superlattice. This property allows us to construct widely tunable far-infrared notch filters with 8.2 dB rejection ratio and terahertz linear polarizers with 9.5 dB extinction ratio, using a superlattice with merely five graphene atomic layers. Moreover, an unpatterned superlattice shields up to 97.5% of the electromagnetic radiations below 1.2 terahertz. This demonstration also opens an avenue for the realization of other transparent mid- and far-infrared photonic devices such as detectors, modulators, and 3-dimensional meta-material systems.Comment: under revie