Metastability and uniqueness of vortex states at depinning

We present results from numerical simulations of transport of vortices in the zero-field cooled (ZFC) and the field-cooled (FC) state of a type-II superconductor. In the absence of an applied current $I$, we find that the FC state has a lower defect density than the ZFC state, and is stable against thermal cycling. On the other hand, by cycling $I$, surprisingly we find that the ZFC state is the stable state. The FC state is metastable as manifested by increasing $I$ to the depinning current $I_{c}$, in which case the FC state evolves into the ZFC state. We also find that all configurations acquire a unique defect density at the depinning transition independent of the history of the initial states.Comment: 4 pages, 4 figures. Problem of page size correcte

Patterns of cognitive dysfunction in progressive MS

Background: Progressive MS is associated with a high frequency of cognitive impairment. However, it is not clear to what extent this reflects global dysfunction, or independent deficits in specific functions

Construction of a Plasmodium falciparum Rab-interactome identifies CK1 and PKA as Rab-effector kinases in malaria parasites

Background information The pathology causing stages of the human malaria parasite Plasmodium falciparum reside within red blood cells that are devoid of any regulated transport system. The parasite, therefore, is entirely responsible for mediating vesicular transport within itself and in the infected erythrocyte cytoplasm, and it does so in part via its family of 11 Rab GTPases. Putative functions have been ascribed to Plasmodium Rabs due to their homology with Rabs of yeast, particularly with Saccharomyces that has an equivalent number of rab/ypt genes and where analyses of Ypt function is well characterized. Results Rabs are important regulators of vesicular traffic due to their capacity to recruit specific effectors. In order to identify P. falciparum Rab (PfRab) effectors, we first built a Ypt-interactome by exploiting genetic and physical binding data available at the Saccharomyces genome database (SGD). We then constructed a PfRab-interactome using putative parasite Rab-effectors identified by homology to Ypt-effectors. We demonstrate its potential by wet-bench testing three predictions; that casein kinase-1 (PfCK1) is a specific Rab5B interacting protein and that the catalytic subunit of cAMP-dependent protein kinase A (PfPKA-C) is a PfRab5A and PfRab7 effector. Conclusions The establishment of a shared set of physical Ypt/PfRab-effector proteins sheds light on a core set Plasmodium Rab-interactants shared with yeast. The PfRab-interactome should benefit vesicular trafficking studies in malaria parasites. The recruitment of PfCK1 to PfRab5B+ and PfPKA-C to PfRab5A+ and PfRab7+ vesicles, respectively, suggests that PfRab-recruited kinases potentially play a role in early and late endosome function in malaria parasites

Characterization of a qubit Hamiltonian using adaptive measurements in a fixed basis

We investigate schemes for Hamiltonian parameter estimation of a two-level system using repeated measurements in a fixed basis. The simplest (Fourier based) schemes yield an estimate with a mean square error (MSE) that decreases at best as a power law ~N^{-2} in the number of measurements N. By contrast, we present numerical simulations indicating that an adaptive Bayesian algorithm, where the time between measurements can be adjusted based on prior measurement results, yields a MSE which appears to scale close to \exp(-0.3 N). That is, measurements in a single fixed basis are sufficient to achieve exponential scaling in N.Comment: 5 pages, 3 figures, 1 table. Published versio

Convection and AGN Feedback in Clusters of Galaxies

A number of studies have shown that the convective stability criterion for the intracluster medium (ICM) is very different from the Schwarzchild criterion due to the effects of anisotropic thermal conduction and cosmic rays. Building on these studies, we develop a model of the ICM in which a central active galactic nucleus (AGN) accretes hot intracluster plasma at the Bondi rate and produces cosmic rays that cause the ICM to become convectively unstable. The resulting convection heats the intracluster plasma and regulates its temperature and density profiles. By adjusting a single parameter in the model (the size of the cosmic-ray acceleration region), we are able to achieve a good match to the observed density and temperature profiles in a sample of eight clusters. Our results suggest that convection is an important process in cluster cores. An interesting feature of our solutions is that the cooling rate is more sharply peaked about the cluster center than is the convective heating rate. As a result, in several of the clusters in our sample, a compact cooling flow arises in the central region with a size R that is typically a few kpc. The cooling flow matches onto a Bondi flow at smaller radii. The mass accretion rate in the Bondi flow is equal to, and controlled by, the rate at which mass flows in through the cooling flow. Our solutions suggest that the AGN regulates the mass accretion rate in these clusters by controlling R: if the AGN power rises above the equilibrium level, R decreases, the mass accretion rate drops, and the AGN power drops back down to the equilibrium level.Comment: 41 pages, 7 figures, accepted for publication in ApJ. Changes in this version: extended discussion of Bondi accretion in clusters, better mass model, new numerical solution

Diagnostic pitfalls of urogenital tuberculosis

Objectives: To describe characteristics, details of diagnosis and outcomes of urogenital tuberculosis (UGTB) in a low-prevalence country. Methods: We conducted a retrospective observational study of 37 consecutive patients diagnosed with UGTB between 1st January 2014 and 31st October 2019 in an East London hospital. Results: 68% (25/37) of patients were male and the median age was 42 years (IQR 34–55). 89% (33/37) of patients were born outside the United Kingdom with 65% (24/37) born in the South Asian region. Renal (32.4%), epididymal (24.3%) and endometrial TB (21.6%) were the most prevalent forms of UGTB. Only 13.5% of UGTB patients had concurrent pulmonary TB. The median length of time from symptom onset to treatment was 163 days, while endometrial TB had an average delay to diagnosis of 564 days. Approximately half of patients with UGTB were culture positive (51.4%). However, 70% of early morning urines (EMUs) sent in urinary TB were culture positive. 11 patients (30.6%) underwent two or more invasive procedures, such as biopsy to obtain specimen samples. The mean treatment length for all UGTB cases was 7.3 months (SD 3.1). Notably, 25% of patients with endometrial TB required surgery despite antituberculous treatment. Conclusions: UGTB is challenging to diagnose as early disease is often asymptomatic. Clinicians faced with non-specific symptoms, or features suggestive of urogenital malignancy amongst patients from TB-endemic areas, should maintain a high suspicion of UGTB

A comparative clinical study of classical and nonclassical Siravyadha in Vipadika

In Ayurveda all the skin diseases are described under single heading i.e. ‘Kushta’ which are further divided into Mahakushta and Kshudrakushta. Vipadika is among the 11 types of Kshudra Kushta involving Vata Kapha mentioned in classics characterized by ‘Panipada Sphutana’ (Fissures in Palms and Soles) and ‘Tivravedana’ (Severe Pain). On basis of its signs and symptoms it can be correlated with ‘Palmoplantar Psoriasis’. Kushtachikitsa is classified into Shodhanam, Shamanam and Nidanparivarjana amongst which Shodhana Chikitsa is of greater significance in skin diseases, and Raktamokshana is considered to be a shortest and effective treatment in the management of skin diseases. Siravyadha is a type of Panchashodhana described by Acharya’s as an effective remedy in number of disease conditions. Acharya Sushruta and Vagbhata has mentioned that Siravyadha is half treatment in Shalyatantra as Basti is the half treatment in Kayachikitsa. Diseases which do not get pacified so quickly by therapeutic measures like Snehana, Swedana etc. are pacified by Siravyadha