Light deflection angle through velocity profile of galaxies in f(R)f(R) model

We explore a new realisation of the galactic scale dynamics via gravitational lensing phenomenon in power-law $f(R)$ gravity theory of the type $f(R)\propto R^{1+\delta}$ with $\delta<<1$ for interpreting the clustered dark matter effects. We utilize the single effective point like potential (Newtonian potential + $f(R)$ background potential) obtained under the weak field limit to study the combined observations of galaxy rotation curve beyond the optical disk size and their lensing profile in $f(R)$ frame work. We calculate the magnitude of light deflection angle with the characteristic length scale (because of Noether symmetry in $f(R)$ theories) appearing in the effective $f(R)$ rotational velocity profile of a typical galaxy with the model parameter $\delta \approx O(10^{-6})$ constrained in previous work. For instance, we work with the two nearby controversial galaxies NGC 5533 and NGC 4138 and explore their galactic features by analysing the lensing angle profiles in $f(R)$ background. We also contrast the magnitudes of $f(R)$ lensing angle profiles and the relevant parameters of such galaxies with the generalised pseudo-isothermal galaxy halo model and find consistency.Comment: 7 pages, 5 figure

Extended galactic rotational velocity profiles in f(R)f(R) gravity background

An attempt has been made to explore the galactic dynamics via the rotational velocity beyond the Einstein's geometric theory of gravity. It is inspired from the geometric relation obtained in the power law $f(R)$ gravity model in vacuum. We analyse the action with a small positive deviation from the Einstein-Hilbert action (taking $R$ as $f(R)\propto R^{1+\delta}$) at the galactic scales for the explanation of cosmological dark matter problem and obtain the contribution of dynamical $f(R)$ background geometry in accelerating the test mass. In the weak field limits, we obtain the effective acceleration of the test mass due to a massive spherically symmetric source in $f(R)$ background and develop an equation for the rotational velocity. We test the viability of the model by tracing the motion of test mass outside the typical galactic visible boundaries without considering any dark matter halo profile. We obtain a nice agreement in the outer regions (up to few tens of kpc beyond the visible boundary) of the typical galaxy by using the known galaxy data.\\ We further explore the galactic dynamics for a galaxy NGC 1052 of which the dark matter deficient galaxies, i.e., DF2 and DF4 are a part (satellite galaxies) and discuss plots of the dynamical feature of rotation curves in $f(R)$ background for the model parameter $\delta<<1$ and interpret the results for its satellite galaxies.Comment: 7 pages, 5 figure

Downs syndrome and its screening: how aware are we?

Background: Down syndrome (DS) is the most common chromosomal abnormality found in live-born babies. The objectives of this study were to assess the knowledge, attitude and practices of pregnant women regarding Down syndrome and its screening.Methods: This was a prospective study done in the Department of Obstetrics and Gynecology, in a tertiary care hospital. All pregnant ladies who attended the antenatal clinic and consented for the study were included. A prevalidated questionnaire was given to these women and data was collected. Responses to pregnant women’s knowledge, attitudes and practices were evaluated in a three-point scale of yes/no/ don’t know. All correct answers or all but one correct answer was scored good and the percentage was calculated.Results: A total of 267 pregnant women were included in the study. Of the 267 women only 156 (58.4%) had heard about Down syndrome. Eighty five percent of the women unanimously agreed that Down syndrome babies had mental impairment. But only 21.1% patients had good knowledge score on Down syndrome. Eleven percent had good knowledge regarding Down syndrome screening tests. Almost sixty five percent of the women had the right attitude towards screening tests and 46.1% patients had followed good practice.Conclusions: Informed decision making rather than imposed decision making must be practiced. Compulsory and effective education regarding Down syndrome and its screening must be provided to all patients at the earliest antenatal visit. The gap between women’s knowledge, theirs attitudes and practice has to be addressed to. Non-invasive prenatal testing might be the future and is quickly bring about a shift in the paradigm in prenatal screening

Simulation of resilient networks

Resilient network is a network, which does not fail under any circumstances. It is the ability of the network to provide and maintain an acceptable level of service in the face of various challenges to normal operation. Disjoint routing strategies are used to calculate disjoint paths, which can be used by the network to route the packet in case of some failure to the existing primary path. Packets arrive at a node in the network in a very random manner. The probability density function for describing the number of such arrivals during a specific period follows the Poisson distribution. The inter-arrival time and the service time at a node follow exponential distribution. As a packet travels from one node to the subsequent node along its path, the packet suffers from different types of delays at each node along the path. Thus the total node delay can be calculated by summing up all the different types of delays. With the increase in traffic and therefore the congestion, the average cost of transmission and retransmission (in the event of a failure) suffers. This varies according to the strategy used for resilience. Routing protocols inherently provide a basic level of resiliency. The ability to “route” around the problem areas defines the efficiency of a routing protocol. However, the time to re-converge the network can vary greatly depending on the protocol being used. When a failure occurs, either the packets can be resent or a new path can be followed from the failure point

Prkci Regulates Autophagy and Pancreatic Tumorigenesis in Mice

Protein kinase C iota (PKCι) functions as a bonafide human oncogene in lung and ovarian cancer and is required for Kras(G12D)-mediated lung cancer initiation and progression. PKCι expression is required for pancreatic cancer cell growth and maintenance of the transformed phenotype; however, nothing is known about the role of PKCι in pancreas development or pancreatic tumorigenesis. In this study, we investigated the effect of pancreas-specific ablation of PKCι expression on pancreatic cellular homeostasis, susceptibility to pancreatitis, and Kras(G12D)-mediated pancreatic cancer development. Knockout of pancreatic Prkci significantly increased pancreatic immune cell infiltration, acinar cell DNA damage, and apoptosis, but reduced sensitivity to caerulein-induced pancreatitis. Prkci-ablated pancreatic acinar cells exhibited P62 aggregation and a loss of autophagic vesicles. Loss of pancreatic Prkci promoted Kras(G12D)-mediated pancreatic intraepithelial neoplasia formation but blocked progression to adenocarcinoma, consistent with disruption of autophagy. Our results reveal a novel promotive role for PKCι in pancreatic epithelial cell autophagy and pancreatic cancer progression

Comparison of a Classification Software based on Image Retrieval with the Off-Line Diagnosis of Expert Endoscopists for probe-based Confocal Laser Endomicroscopy (pCLE) of Colorectal Polyps

Gastrointestinal Endoscopy (DDW 2012)BACKGROUND AND AIMS pCLE (Cellvizio, Mauna Kea Technologies) enables in vivo microscopic imaging of the epithelium in real-time during ongoing endoscopy. An image retrieval software prototype for automatic classification of pCLE images, recently developed to assist the endoscopists in the in vivo pCLE diagnosis of colorectal polyps, has the great potential of decreasing inter-observer agreement while increasing diagnostic performance of endoscopists. This study aims at comparing the performances of the classification software with the performance of pCLE diagnosis established off-line by expert endoscopists. METHODS Intravenous fluorescein pCLE imaging of colorectal lesions was performed on patients undergoing surveillance colonoscopies, followed by polypectomies. Histopathology was used as gold standard for the differentiation between neoplastic and non-neoplastic lesions. The pCLE sequences, recorded for each polyp, were analyzed off-line by 2 expert endoscopists, blinded to the endoscopic characteristics and histopathology. These pCLE videos, along with their histopathology diagnosis, were used to train the classification software which is a content-based image retrieval technique followed by k-nearest neighbor classification. All evaluations were performed using leave-onepatient- out (LOPO) cross-validation to avoid bias. RESULTS 135 colorectal lesions, including 6 serrated adenoma cases, were imaged in 71 patients. Based on histopathology, 93 of these 135 lesions were neoplastic and 42 were non-neoplastic. No statistical significance was found for the difference between the performance of software classification (accuracy 89.6%, sensitivity 92.5%, specificity 83.3%, using LOPO) and the performance of off-line diagnosis of pCLE established by the expert endoscopists (accuracy 89.6%, sensitivity 91.4%, specificity 85.7%). The 95% confidence intervals for equivalence testing (−0.073 to 0.073 for accuracy, −0.068 to 0.089 for sensitivity, −0.18 to 0.13 for specificity) are sufficiently small to suggest statistical equivalence. The −0.18 lower bound for the specificity should be sufficient if the classification software is only taken as a second-reader tool to support pCLE diagnosis. CONCLUSIONS The image retrieval software for automatic classification of pCLE sequences of colorectal polyps achieves a high performance which is statistically comparable to that of off-line diagnosis of pCLE sequences established by expert endoscopists. A fortiori, the classification software should be useful, not only to train non expert endoscopists, but also to assist any endoscopist in in vivo pCLE diagnosis. DISCUSSION The proposed software is not a "black box" but an informative tool based on the query by example model that produces, as intermediate results, visually similar annotated pCLE videos directly interpretable by the endoscopist