Squeezing out the last 1 nanometer of water: A detailed nanomechanical study

In this study, we present a detailed analysis of the squeeze-out dynamics of nanoconfined water confined between two hydrophilic surfaces measured by small-amplitude dynamic atomic force microscopy (AFM). Explicitly considering the instantaneous tip-surface separation during squeezeout, we confirm the existence of an adsorbed molecular water layer on mica and at least two hydration layers. We also confirm the previous observation of a sharp transition in the viscoelastic response of the nanoconfined water as the compression rate is increased beyond a critical value (previously determined to be about 0.8 nm/s). We find that below the critical value, the tip passes smoothly through the molecular layers of the film, while above the critical speed, the tip encounters "pinning" at separations where the film is able to temporarily order. Pre-ordering of the film is accompanied by increased force fluctuations, which lead to increased damping preceding a peak in the film stiffness once ordering is completed. We analyze the data using both Kelvin-Voigt and Maxwell viscoelastic models. This provides a complementary picture of the viscoelastic response of the confined water film

Polyglucosan bodies in medullary catecholaminergic neurones in SUDEP

Polyglucosan bodies have been reported in the context of hypoxic-ischaemic perinatal brain injury, mainly in the pallidum but with rare reports in brainstem neurones. We report a case of a five year old boy with cerebral palsy, complex neurology and epilepsy with a sudden nocturnal death. At post-mortem long-standing bilateral necrosis of basal ganglia and hippocampal atrophy was identified in keeping with hypoxic-ischaemic perinatal injury. In addition numerous polyglucosan bodies, which were PAS, p62 and ubiquitin positive, were noted in brainstem neurones and dendrites, primarily involving the ventrolateral and dorsomedial medulla. Immunohistochemistry confirmed relative preservation of medullary neuronal populations in the reticular formation, including catecholaminergic (tyrosine hydroxylase, TH), serotonergic (tryptophan hydroxylase) and neurokinin1 receptor/somatostatin positive neurones. The polyglucosan bodies predominated in catecholaminergic neurones which could indicate their selective vulnerability and a functional deficiency, which during a critical peri-ictal period contributed to the sudden death in epilepsy

Review: Neuropathology findings in autonomic brain regions in SUDEP and future research directions

Autonomic dysfunction is implicated from clinical, neuroimaging and experimental studies in sudden and unexpected death in epilepsy (SUDEP). Neuropathological analysis in SUDEP series enable exploration of acquired, seizure-related cellular adaptations in autonomic and brainstem autonomic centres of relevance to dysfunction in the peri-ictal period. Alterations in SUDEP compared to control groups have been identified in the ventrolateral medulla, amygdala, hippocampus and central autonomic regions. These involve neuropeptidergic, serotonergic and adenosine systems, as well as specific regional astroglial and microglial populations, as potential neuronal modulators, orchestrating autonomic dysfunction. Future research studies need to extend to clinically and genetically characterized epilepsies, to explore if common or distinct pathways of autonomic dysfunction mediate SUDEP. The ultimate objective of SUDEP research is the identification of disease biomarkers for at risk patients, to improve post-mortem recognition and disease categorisation, but ultimately, for exposing potential treatment targets of pharmacologically modifiable and reversible cellular alterations

Role of community health nurse in earthquake affected areas

The role of Community Health Nurses (CHNs) outside the traditional hospital setting is meant to provide and promote the health care needs of the community. Such nurses can play a substantial role in the community setting including emergencies like disasters. This became evident after the earthquake of October 8, 2005 in Pakistan. The objective was to address the issues, faced by primary healthcare providers working in earthquake-affected areas focusing on participatory approach. The experience of the interventions done by CHN by a guided frame work (assessment, planning, implementation and evaluation components) is described. Issues identified by CHN included: lack of training of health care providers, lack of collaboration, communication between the medical and management staff due to poor infrastructure of the healthcare facilities. The interventions were carried out, utilizing existing resources. Efforts were directed to build capacity of health care providers at grass root level to fill in gaps of health care delivery system for sustainable change. Overall, working in the earthquake affected areas is challenging. Health leadership should foresee role of CHN in emergencies where quality healthcare interventions are essential

Fiber-assisted detection with photon number resolution

We report the development of a photon-number resolving detector based on a fiber-optical setup and a pair of standard avalanche photodiodes. The detector is capable of resolving individual photon numbers, and operates on the well-known principle by which a single mode input state is split into a large number (eight) of output modes. We reconstruct the photon statistics of weak coherent input light from experimental data, and show that there is a high probability of inferring the input photon number from a measurement of the number of detection events on a single run.Comment: 4 pages, 2 figures; Submitted for publicatio

Heliophysics Event Knowledgebase for the Solar Dynamics Observatory and Beyond

The immense volume of data generated by the suite of instruments on SDO requires new tools for efficient identifying and accessing data that is most relevant to research investigations. We have developed the Heliophysics Events Knowledgebase (HEK) to fill this need. The HEK system combines automated data mining using feature-detection methods and high-performance visualization systems for data markup. In addition, web services and clients are provided for searching the resulting metadata, reviewing results, and efficiently accessing the data. We review these components and present examples of their use with SDO data.Comment: 17 pages, 4 figure

Cognitive and psychomotor effects of adjunctive aripiprazole or paliperidone in patients of schizophrenia receiving olanzapine: a double blind placebo controlled clinical study

Background: Emergence of atypical antipsychotics has revolutionized the treatment of schizophrenia by exploiting dual actions on serotonin as well as dopaminergic receptors. Still, monotherapy with these agents is insufficient to control cognitive and psychomotor as well as positive and negative symptoms. Hence combination therapy with antipsychotics is common in clinical practice. Objective of current study is to compare the effects of addition of aripiprazole or paliperidone on cognition and psychomotor functions in schizophrenia receiving olanzapine.Methods: This is prospective, double blind, placebo controlled, parallel group study in 90 patients of schizophrenia showing partial or no response to olanzapine measured by Positive And Negative Symptoms Score (PANSS) scale. They were randomly divided to receive adjuvant aripiprazole, paliperidone or placebo for 6 weeks.Results: Combination of aripiprazole and olanzapine shows significant improvement in most of the cognition and psychomotor parameters like attention, perception, verbal memory, thinking and processing as well as motor speed while combination of paliperidone and olanzapine is associated with improvement in only some of the cognitive and psychomotor parameters such as attention, perception and verbal memory only. Both the combinations are efficacious in controlling positive and negative symptoms of schizophrenia as assessed by PANSS scale.Conclusions: The best augmenting strategy with for olanzapine nonresponsive patients will be D2 receptor partial agonist like aripiprazole rather than D2 antagonist like paliperidone and other atypical antipsychotic agents for better improvement in cognition and psychomotor domains