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Below-and aboveground abundance and distribution of fungal entomopathogens in experimental conventional and organic cropping systems
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No full textAbstract: This is a follow up study of a cohort of academic retirees in retrospective in a well based record assessment. In this study, a preliminary survey was made to determine the mortality and survival profile of retired academic staff retirees of University of Ibadan in Nigeria. From total population of 302 of pensionable 60 to 65 years of age of service and 35 years in service as at year 2012 of retired academic staff retirees surveyed, 109 were randomly selected during the study dates "January 1977 to December 2012". Simple descriptive frequency count and the Life Table model were identified as the most suitable approach to analyze the demographic characteristics and pattern of mortality; this provides estimates of probabilities of surviving a given number of years after retirement. Since life table is non-parametric procedure for estimating life expectancy at different points and does not produce a measure of precision. We utilised the distribution of the survival and hazard function to give a more elegant and measure precision of life expectancy. The survival probability curves for the males and females respondents indicate that there is no significant difference in the survival probability for the two groups using Mantel-cox test with probability 0.287. There is significant difference between mortality rate of voluntary and compulsory ages of retirees during the period of study of retired academic staff of the university. The survival probability of gender and their duration of service are not significant with probability 0.738, thus one could infer that duration of service before retirement does not have effect on longevity of retired academic staff of the university. The University academic retirees' median residual life time is 9.07 years
Pharmacological Characterization of (E)-N-(4-Fluorobut-2-enyl)- 2-carbomethoxy-3-(4Ј-tolyl)nortropane (LBT-999) as a Highly Promising Fluorinated Ligand for the Dopamine Transporter
No full textABSTRACT In the aim to develop an efficient fluorinated probe for positron emission tomography (PET) exploration of the dopamine transporter (DAT), we studied several in vitro and in vivo characteristics of the phenyltropane derivative (E)-N-(4-fluorobut-2-enyl)-2-carbomethoxy-3-(4Ј-tolyl)nortropane (LBT-999). In vitro on rat striatal membrane, [ 3 H]LBT-999 bound to a single site with a K d of 9 nM, B max of 17 pmol/mg protein, and a very high selectivity for the DAT [IC 50 for 1-{2-[bis-(4-fluorophenyl)-methoxy]ethyl}-4-(3-phenylpropyl)piperazine (GBR 12909) and (E)-N-(3-iodoprop-2-enyl)-2-carbomethoxy-3-(4Ј-methylphenyl)nortropane (PE2I): 2.4 and 18 nM, respectively; IC 50 for paroxetine, citalopram, N,N-dimethyl-2-(2-amino-4-methylphenyl thio)benzylamine, nisoxetine, and desipramine Ͼ1 M]. In vitro on post-mortem human brain sections, LBT-999 bound with high intensity to the caudate-putamen, weakly to the thalamus, and not in the neocortex and cerebellum. This binding was totally abolished in the presence of PE2I. Ex vivo cerebral biodistribution of [ 11 C]LBT-999 in rats showed striatum/ cerebellum radioactivity ratios of 18 and 25 at 30 and 60 min postinjection, respectively. This accumulation was strongly prevented by preinjection of GBR 12909, whereas paroxetine and nisoxetine had no effect. An in vivo kinetic PET study in three baboons showed a fast and very high uptake in the striatum, with a plateau at 30 min postinjection and a maximal putamen/ cerebellum ratio of 30. Taken together, these findings demonstrate that LBT-999 is a highly promising agent for in vivo exploration of the DAT. This probe is currently labeled with 18 F for further characterizations. As the membrane dopamine transporter (DAT) is very involved in a number of brain functions, in vivo exploration of this molecular target could become a relevant tool for the knowledge of pathophysiological mechanisms and diagnosis and follow-up of several neurological and psychiatric conditions. In this field, scintigraphic exploration of the DAT could be very useful for the early diagnosis and follow-up of Parkinson's disease. Most of these studies have been performed using single photon emission computerized tomography with radioligands chemically derived from the cocaine structure and labeled with 123 I such as 2-carbomethoxy-3-(4-iodophenyl)tropane ABBREVIATIONS: DAT, dopamine transporter; FPCIT
X-RAY PRODUCTION USING LASER-PLASMA ACCELERATORS
No full textAbstract: Bubble regime has been investigated using three-dimensional particle-in-cell simulations of ultra-relativistically intense laser pulses with duration a fraction of the plasma wavelength Electrons trapped inside the bubble experience an electrostatic force and undergo betatron motion. The present work analyzes the spontaneous radiation emitted by electrons undergoing betatron motion in the plasma bubble. Numerical simulations have been used to calculate the expected spectra and spatial distribution of the radiation. We discuss these theoretical results and an experiment at Strathclyde that is being set up to measure the betatron radiation. Laser-plasma accelerators and betatron oscillations: A light source capable of delivering pulses of X-rays with femtosecond duration should provide a new probe with a time resolution that would enable investigation of the evolution of molecular and solid state matter. Laser-plasma accelerators represent a new interesting way of generating short pulses of X-rays. The mechanism determining X-ray emission can be sketched through the following steps: -The propagation of intense laser pulses in underdense plasma generates plasma waves: laser wakefield acceleration (LWFA) occurs when a laser pulse travelling at a velocity close to the speed of light excites a trailing plasma wave or wake through the action of the ponderomotive force which expels electrons from regions of high laser intensity. -Electrons can be trapped in the wake and surf the electric field of the wake thus gaining energy from the wave . -If an intense laser pulse is ultra-relativistic and its duration shorter than the plasma wavelength, the ponderomotive force will expel plasma electrons radially and leave a cavitated (bubble) region behind the pulse, surrounded by a high electron density region. -Electrons are trapped at the rear of the bubble and accelerate along the laser axis, creating a beam with a radial and longitudinal size much smaller than the laser spot diamete
dopamine D 5 receptors (Tiberi and Caron, 1994), serotonin 5-HT 2C recep-tors
No full textABSTRACT Single amino acid mutations in the third intracellular loop, as well as other domains of G protein-coupled receptors, have been shown to confer drastic changes in receptor properties and have been postulated to be responsible for various disease states. To determine whether an amino acid mutation can confer dramatic alterations in the 5-hydroxytryptamine 2A (5-HT 2A ) receptor, we mutated amino acid 322 to lysine (C322K), glutamate (C322E) or arginine (C322R). Transient expression of the mutant receptors revealed properties associated with constitutive activity. Radioligand binding studies revealed an increase in 5-HT affinity from 293 nM (native) to 86 nM (C322E), 25 nM (C322K) and 11 nM (C322R). 5-HT potency for stimulation of inositol phosphate production increased from 152 nM (native) to 61 nM (C322E) and 25 nM (C322K). Basal inositol phosphate levels in COS-7 cells expressing C322K and C322E mutant receptors were 8-fold and 4-fold higher, respectively, than cells expressing native 5-HT 2A receptors. Basal levels of inositol phosphate stimulated by C322K receptors represented 48% of total inositol phosphate production stimulated by native receptors in the presence of 10 M 5-HT. Antipsychotic drugs (chlorpromazine, clozapine, haloperidol, loxapine and risperidone) displayed inverse agonist activity by inhibiting C322K constitutive activation of phosphatidylinositol hydrolysis. These data indicate that amino acid 322 in the 5-HT 2A receptor plays an important role in maintaining the inactive conformation and provide further evidence that amino acid mutations can produce profound alterations in G protein-coupled receptor activity. The third intracellular loop of GPCR has been identified as a region that is crucial for receptor/G protein interactions (Strader et al., 1987; Recently, several GPCR have exhibited constitutive activity in vivo. Naturally occurring amino acid mutations in the luteinizing hormone recepto
Blame on Them, Shame on Us: Combining Affective and Normative Behaviour in Intelligent Virtual Agents (Extended Abstract)
No full textABSTRACT Virtual environments often try to simulate situations where agents should display socially acceptable behaviour, as described by social norms. Actions that fulfil or violate norms can be potential sources for emotions, not just for the agent responsible, but for all agents that witness the event. We claim that the type and intensity of those emotions depends, not only on the salience (importance) of the norm, but also on the social relations between agents. We present a model to generate emotions triggered by a norm-related event, based on a subjective evaluation (appraisal) of this event made by every agent that witnessed it. This appraisal takes into account the salience of the norms and the social relations in order to create more believable agents
Experimental and Numerical Analyses of Sloshing Flows
No full textAbstract Recently the demand of sloshing analysis is rising for building large LNG carriers and LNG platforms. This study considers the experimental and numerical observations on strongly nonlinear sloshing flows in ship cargo and their coupling effects with ship motion. Violent sloshing flows in experiments are observed, and two different numerical methods, finite difference method and smoothed particle hydrodynamics (SPH) method, are applied for the simulation of violent sloshing flows. Several physical issues are introduced in the analysis of sloshing flows, and the corresponding numerical models are described. This study demonstrates that the physics-based numerical schemes are essential in the prediction of violent sloshing flow and sloshing-induced impact pressure. To study the sloshing effects on ship motion, a ship motion program based on impulsive response function (IRF) is coupled with the developed numerical models for sloshing analysis. The results show that the nonlinearity of sloshinginduced forces and moments plays a critical role in the coupling effects
Instructional Design and Learning Theory on the Development of a Multimedia Courseware
No full textAbstract-This paper discusses on the possibility of taking advantage of the well-served Gagne's theory of learning and combining it with the benefits of instructional design. Such potent combination can surely be extended further with the integration of advanced multimedia is undoubtedly helpful in today's education realm. The best of all these factors may have a positive impact on the teaching and learning scenario. Hopefully it has an optimistic bearing on the study of computer programming for non-computer science students when an interactive multimedia application is developed based on Gagne's theory of learning
Servant Leadership and Public Administration: Solving the Public Sector Financial Problems Through Service
No full textAssociation between Metformin Use and Cancer Stage at Diagnosis among Elderly Medicare Beneficiaries with Preexisting Type 2 Diabetes Mellitus and Incident Prostate Cancer
No full textObjective. To examine the association between metformin use and cancer stage at diagnosis among elderly men with preexisting diabetes mellitus and incident prostate cancer. Methods. This study used a population-based observational cohort of elderly men (≥66 years) with preexisting diabetes and incident prostate cancer between 2008 and 2009 ( = 2, 652). Cancer stage at diagnosis (localized versus advanced) was based on the American Joint Cancer Committee classification. Metformin use and other independent variables were measured during the one year before cancer diagnosis. Logistic regressions with inverse probability treatment weights were used to control for the observed selection bias. Results. A significantly lower percentage of metformin users were diagnosed with advanced prostate cancer as compared to nonusers (4.7% versus 6.7%, < 0.03). After adjusting for the observed selection bias and other independent variables, metformin use was associated with a 32% reduction in the risk of advanced prostate cancer (adjusted odds ratio, AOR: 0.68, 95% confidence interval, CI: 0.48, 0.97). Conclusions. This is the first epidemiological study to support the role of metformin in reducing the risk of advanced prostate cancer. Randomized clinical trials are needed to confirm the causal link between metformin use and prostate cancer diagnosis stage