ROLES OF MICRORNAS IN PLANT ABIOTIC STRESS, DEVELOPMENT AND VIRAL INFECTION

Plant microRNAs play important roles in plant growth and development. Here we investigated the roles of miRNAs in the plant abiotic stress, development and viral infection. MicroRNA membrane array analysis using five different abiotic stress treatments resulted in the identification of 8 novel stress inducible miRNA-families. Functional studies on novel stress inducible miR168 revealed its functional relation with abiotic stress. Over expression of miR168 in Arabidopsis showed upregulation of four stress related miRNAs (miR163, miR167, miR398 and miR408). Analysis of 9 independent transgenic lines showed induction of miR398, an oxidative stress responsive miRNA with a corresponding down regulation of its target genes. Heavy metal oxidative stress tolerance bioassays confirmed the susceptibility of transgenics compared to the wild types indicating the fact that the miR168 is indirectly involved in plant abiotic stress by inducing other stress responsive miRNAs. MicroRNAs are highly conserved across the plant kingdom. A miRNA atlas was drafted for different tomato organs and fruit stages using the known miRNA sequences from different plants species. A large variation in both number and level of miRNA expression pattern was observed among different organs as well as among fruit stages. In the present investigation, we have found a window of expression for different miRNAs during the fruit development. A gradual decrease in the expression levels of miR160h, miR167a and miR399d and a gradual increase in miR164a have been noticed towards the fruit maturation while miR398b showed dual peaks during fruit development indicating a potential role of various miRNAs in fruit development and maturation. Sonchus yellow net virus (SYNV) infected Nicotinana benthamiana leaves showed severe disease symptoms at two weeks post infection (WPI) and gradually recovered from the SYNV infection after 4-5 WPI correlating with the overall miRNA levels. The miRNA array and northern analysis showed an overall reduction of miRNA biogenesis during 2WPI followed by restoration to normal levels supporting the idea that the SYNV indeed interfered with the host miRNA levels which caused the symptoms and recovery phenotypes. Overall studies on plant abiotic stress, development and viral infection showed important roles of miRNAs in different aspects of plant life

Yield of Diagnostic Tests in the Evaluation of Syncopal Episodes in Older Patients

ABSTRACT: YIELD OF DIAGNOSTIC TESTS IN THE EVALUATION OF SYNCOPAL EPISODES IN OLDER PATIENTS Mallika L. Mendu, Gail McAvay, Rachel Lampert, Jonathan Stoehr, Mary E. Tinetti, Department of Internal Medicine, Department of Epidemiology and Public Health Yale University, School of Medicine, New Haven, CT Syncopal episodes are common among older adults; etiologies range from benign to life-threatening. We determined the frequency, yield, and costs of tests obtained to evaluate older persons with syncope. We also calculated the cost per test yield and determined whether the San Francisco Syncope Rule (SFSR) improved test yield. Review of 2,106 consecutive patients 65 years and older admitted following a syncopal episode. Electrocardiograms (99%), telemetry (95%), cardiac enzymes (95%), and head computed tomography (CT) (63%) were the most frequently obtained tests. Cardiac enzymes, CTs, echocardiograms, carotid ultrasounds, and electroencephalography all affected diagnosis or management in \u3c5% of cases and helped determine etiology of syncope \u3c 2% of the time. Postural blood pressure, performed in only 38% of episodes, had the highest yield with respect to affecting diagnosis (18-26%) or management (25-30%) and determining etiology of the syncopal episode (15-21%). The cost per test affecting diagnosis or management was highest for electroencephalography ($32,973), CT ($24,881), and cardiac enzymes ($22,397) and lowest for postural blood pressure ($17-$20). The yields and costs for cardiac tests were better among patients meeting, than not meeting, SFSR. For example, the cost per cardiac enzymes affecting diagnosis or management was$10,331 in those meeting, versus $111,518 in those not meeting, the SFSR. Many unnecessary tests are obtained to evaluate syncope. Selecting tests based on history and examination and prioritizing less expensive and higher yield tests would ensure a more informed and cost-effective approach to evaluating older patients with syncope

Design of a fiber optic oxygen sensor based on immobilized hemoglobin

The fiber optic Oxygen sensor consists of a thin layer of immobilized deoxyhemoglobin at the common end of a bifurcated fiber. Immobilization is done using the alginate gel procedure. The immobilized reagent is separated from the standard oxygen sample by the gel with or without semi-permeable membrane, and the entire configuration is enclosed in an oxygen free sample cell. Light from a tungsten-halogen lamp, filtered through a 405nm filter is passed through one arm of a bifurcated fiber to the sample cell. The reflected intensity (a highly polished aluminum foil or a plate is placed at the bottom of the sample cell ) from the other arm of the bifurcated fiber is measured using a photomultiplier tube and a power meter. The above procedure is repeated for a 435 nm filter. The ratio of the reflected intensities at 435nm and 405nm gives an indication of the concentration of oxygen in the standard samples. Since this is a ratio measurement, it is insensitive to slow loss of reagent and drift. The reflected intensities decrease with increase in the amount of deoxyhemoglobin and with increase in the thickness of the immobilized layer. Precautions should be taken to prevent the oxidation of hemoglobin to methemoglobin. Response time is an important factor in determining the time required for equilibrium to be attained. It takes about 3 minutes to reach equilibrium for a 0.5mm thick layer of immobilized deoxyhemoglobin, coated with the membrane and 2 minutes without the membrane

MHD Boundary Layer Flow of a Nanofluid Past a Wedge

AbstractThis paper analyzes the steady laminar magnetohydrodynamic (MHD) flow, heat and mass transfer characteristics in a nanofluid over a wedge in the presence of a variable magnetic field. The governing nonlinear partial differential equations are transformed into a system of ordinary differential equations using similarity variables and then solved numerically by using spectral quasi linearization method (SQLM). The present numerical results are validated by favourable comparisons with previously published ones as the special cases of the present investigations. The effects of magnetic parameter, Falkner-Skan power-law parameter and the volume fraction parameter on the non-dimensional heat and mass transfer rates are presented graphically

Multiscale characterization of mechanical and fracture properties of cortical bone specimens

Bone is a hierarchical material with multiple length scales ranging from mineralized collagen fibrils at the nanoscale, single lamella at the sub microscale, lamellar structure at the microscale, osteons at the mesoscale to a whole bone at the macroscale. Several fracture testing methods are available including the three-point bending test, the compact tension test and the double cantilever test. However, these methods are confined to the macroscopic scale. At the microscopic scale, Vickers Fracture Indentation was proposed. Nevertheless, the study observed instances of varied crack lengths making it irreproducible and thus there is a need for further advancement on the testing front at the lower length scales. The research objective is to measure the fracture properties of bone at the level of osteons and at lower length scales using scratch testing. Cortical Bone Specimens obtained from porcine and bovine femurs have been cut, ground, polished and tested using an arduous experimental procedure. The nature of the fracture observed exhibited a strong anisotropy with toughening mechanisms and a competition between plastic flow and brittle fracture. Scanning Electron Microscopy revealed the presence of micro cracking, crack bridging, crack deflection and flaking or chipping along the length of the scratch. The process of applying nonlinear fracture mechanics methodologies such as the J-integral or the energetic size effect law in the analysis used to determine the fracture toughness of bone was meticulous. The results of this investigation showed not only a coupling between elasticity and fracture characteristics but also a mixed mode fracture involved in the determination of the fracture resistance. The investigation employs scratch tests which determine the fracture properties not only at the microscale but also at the lower length scales due to the scalability of the scratch tests. Furthermore, nanoindentation tests were conducted on cortical bone specimens to determine their mechanical properties. Due to the viscoelasticity and viscoplasticity exhibited by cortical bone specimens, creep induced rate effect studies were carried out and their influence on the fracture properties was studied. The presented research paves the way towards a deeper understanding of the fragility of hard biological tissues. The knowledge gained could be applied to inform novel treatment for bone diseases, prevention of bone brittlement and design of advanced structural materials

A pattern of serious adverse drug reactions reported in a tertiary care hospital, Rangaraya Medical College, Kakinada, Andhra Pradesh

Background: Serious adverse drug reactions (ADRs) constitute a major limitation in clinical development of a drug thus necessitating close monitoring. Studies regarding the pattern of serious ADRs are limited in southern India. The present study was conducted in tertiary care hospital in Andhra Pradesh with an objective to evaluate the pattern of severe cutaneous and non-cutaneous ADRs in our hospital and to assess the causality, severity, and preventability of these reactions.Methods: A retrospective observational study was conducted over two years, from January 2016 till January 2018 in our ADR monitoring center. The pattern of serious adverse drug reactions, the nature of ADR, suspected drug, the outcome and preventability were analyzed using Modified Hartwig and Siegel scale, and modified Schumock and Thorton scale.Results: Out of 734 ADRs reported, 42 were serious, while 692 were non-serious. Out of 42, 22 were dermatological in origin while the others were acute kidney injury, acute psychosis, febrile neutropenia, gynecomastia, and lipodystrophy. According to WHO causality assessment scale, 27 were probable while 15 were possible. The majority were reported in the age group of 16 to 65 years with female (34) preponderance. The most common drug category responsible was antimicrobials, followed by antiretrovirals, anti-epileptics, and analgesics.Conclusions: Antimicrobial, anti-epileptics, and analgesics contributed to serious ADRs. Although non-cutaneous ADRs did not result in hospitalization, they caused social inhibition and mental stress in the patient

A critical review of 'optimal' annuitization strategies

This paper is an analysis of different self-annuitization strategies advised to a retiree. At the time of retirement, an individual has the choice between annuitizing immediately with their wealth or delaying until a future date while making the most from returns earned through financial markets. This is a similar structure to how a Defined Contribution (DC) pension plan works. Various researchers have assisted retirees on this dilemma of whether or not to annuitize. They designed strategies that work under general market settings and any individual preferences that maximize the income generation. However, these studies assume that individuals are making decisions as if they are maximizing or behaving optimally. In reality, what might be ``optimal" in a general sense may not match the optimality defined in a normative sense of giving advice. The effect of the gap between the prescribed and descriptive nature of this advice is not well discussed in the current literature. Our motivation comes from examining the prescriptive nature of the strategies with respect to downside risk. In this paper, we choose three different self-annuitization strategies, from three different papers: Milevsky (2001), Milevksy and Young (2007) and Giacinto and Vigna (2012). The strategies proposed in these papers provide normative advice to retirees on if and when to annuitize in retirement years. While an attempt is made to minimize the risk of outliving their own assets and maximize the risk-reward trade-off. The main concern should be the elicited risk in adopting these strategies and doing poorly. In the retirement years, it could be more catastrophic to an individual if he/she runs out of money by following the normative solutions proposed through these strategies. For an average retiree who has limited financial literacy or deteriorating cognitive abilities, it is highly challenging to have their future secured without the fear of inadequate income. Thus, we use risk measures to review the given literature on various plausible explanations of their working strategy and assess the risk of compromising income security. We implement modern world parameters into these strategies to assess if they are truly delivering sound advice