EVALUATION OF PHYTOCHEMICAL CONSTITUENTS AND ANTIMICROBIAL ACTIVITY OF SILVER NANOPARTICLE SYNTHESIZED IPOMOEA NIL AGAINST SELECTED PATHOGENS

ABSTRACTObjective: The objective of this study is to investigate a simple and feasible approach for the production of silver nanoparticles (AgNPs) by using leafextract of Ipmoea nil and to evaluate its antibacterial activity.Methods: The AgNPs synthesized was characterized by a change in color and the absorption peaks by ultraviolet-visible spectroscopy. The phytocompounds responsible for the reduction and capping of silver ions was known from Fourier transform infrared spectra and phytochemical analysis.The antibacterial effects of prepared aqueous AgNPs were detected against five types of pathogenic bacteria, including Gram-negative and Grampositivebacteria (Escherichia coli, Salmonella, Bacillius, Proteus, and Klebsilla pneumonia) using agar well diffusion method.Results: A peak absorption value between 400 and 450 nm and the color change of the extract from yellowish to red wine were corresponds tothe plasmon absorbance of AgNPs. On the other hand, aqueous extract of I. nil mediated AgNPs found to be effective against tested microorganisms(Salmonella, Bacillus, and Proteus) with inhibition zone in the range of 10-13 mm (20 μl and 10 μl) except E. coli and K. pneumonia. Furthermore,aqueous extract of I. nil leaves had no ability to suppress the growth of the tested microorganisms in the concentration of 10 μl. The control alsoproduced similar inhibition zones like AgNPs.Conclusions: Our findings indicated that green synthesized AgNPs mediated by I. nil leaf extract had an efficient anti-bactericidal activity against thebacterial species tested. Hence, further studies are needed to highlight its mechanism and application as an antibacterial agent.Keywords: Ipomoea nil, Silver nanoparticles, Antibacterial activity, Bacteria

Human Posterior Parietal Cortex Plans Where to Reach and What to Avoid

In this time-resolved functional magnetic resonance imaging (fMRI) study, we aimed to trace the neuronal correlates of covert planning processes that precede visually guided motor behavior. Specifically, we asked whether human posterior parietal cortex has prospective planning activity that can be distinguished from activity related to retrospective visual memory and attention. Although various electrophysiological studies in monkeys have demonstrated such motor planning at the level of parietal neurons, comparatively little support is provided by recent human imaging experiments. Rather, a majority of experiments highlights a role of human posterior parietal cortex in visual working memory and attention. We thus sought to establish a clear separation of visual memory and attention from processes related to the planning of goal-directed motor behaviors. To this end, we compared delayed-response tasks with identical mnemonic and attentional demands but varying degrees of motor planning. Subjects memorized multiple target locations, and in a random subset of trials targets additionally instructed (1) desired goals or (2) undesired goals for upcoming finger reaches. Compared with the memory/attention-only conditions, both latter situations led to a specific increase of preparatory fMRI activity in posterior parietal and dorsal premotor cortex. Thus, posterior parietal cortex has prospective plans for upcoming behaviors while considering both types of targets relevant for action: those to be acquired and those to be avoided

Space representation for eye movements is more contralateral in monkeys than in humans

Contralateral hemispheric representation of sensory inputs (the right visual hemifield in the left hemisphere and vice versa) is a fundamental feature of primate sensorimotor organization, in particular the visuomotor system. However, many higher-order cognitive functions in humans show an asymmetric hemispheric lateralization—e.g., right brain specialization for spatial processing—necessitating a convergence of information from both hemifields. Electrophysiological studies in monkeys and functional imaging in humans have investigated space and action representations at different stages of visuospatial processing, but the transition from contralateral to unified global spatial encoding and the relationship between these encoding schemes and functional lateralization are not fully understood. Moreover, the integration of data across monkeys and humans and elucidation of interspecies homologies is hindered, because divergent findings may reflect actual species differences or arise from discrepancies in techniques and measured signals (electrophysiology vs. imaging). Here, we directly compared spatial cue and memory representations for action planning in monkeys and humans using event-related functional MRI during a working-memory oculomotor task. In monkeys, cue and memory-delay period activity in the frontal, parietal, and temporal regions was strongly contralateral. In putative human functional homologs, the contralaterality was significantly weaker, and the asymmetry between the hemispheres was stronger. These results suggest an inverse relationship between contralaterality and lateralization and elucidate similarities and differences in human and macaque cortical circuits subserving spatial awareness and oculomotor goal-directed actions

Getting Around When You’re Just Getting By: The Travel Behavior and Transportation Expenditures of Low-Income Adults, MTI Report 10-02

How much do people with limited resources pay for cars, public transit, and other means of travel? How does their transportation behavior change during periods of falling employment and rising fuel prices? This research uses in-depth interviews with 73 adults to examine how rising transportation costs impact low-income families. The interviews examine four general areas of interest: travel behavior and transportation spending patterns; the costs and benefits of alternative modes of travel; cost management strategies; and opinions about the effect of changing transportation prices on travel behavior. Key findings include: Most low-income household are concerned about their transportation costs. Low-income individuals actively and strategically manage their household resources in order to survive on very limited means and to respond to changes in income or transportation costs. In making mode-choice decisions, low-income travelers—like higher-income travelers—carefully evaluate the costs of travel (time and out-of-pocket expenses) against the benefits of each of the modes. Some low-income individuals in our sample were willing to endure higher transportation expenditures—such as the costs of auto ownership or congestion tolls—if they believed that they currently benefit or would potentially benefit from these increased expenses. Although low-income households find ways to cover their transportation expenditures, many of these strategies had negative effects on households. The report concludes with recommendations on how to increase transportation affordability, minimize the impact that new transportation taxes or fees have on low-income people, and develop new research and data collection to support the previous two efforts

Estimating Volatility in Prices of Pulses in India: An Application of Garch Model

Although, India is the largest pulse producing country in the world, the production of these crops in the country has shown sluggish growth over the years. Low growth rate coupled with high fluctuations in production of pulses is mainly responsible for poor performance of pulse sector. It also leads to high price variability. Variability in the prices of pulses is a major concern for decision makers. This study was conducted to estimate the volatility in the prices of major pulses (chickpea, pigeonpea, blackgram, greengram and lentil) in India using GARCH model. Results have shown that the volatility in the current period depends on volatility in the preceding period in case of pulses as evident from the significant ARCH term for all the crops. Further, the sum of α and β coefficients has been found more than one for all the pulse crops except pigeonpea in period I thus indicating an explosive price series with a tendency to meander away from mean value. The volatility in the price series of pigeonpea has been found more persistent and explosive in recent period. So, there is a need for regular monitoring of prices and appropriate interventions by the government, when necessary, to make the development of pulse sector more sustainable

Steroidi i poliketidi iz kore biljke Uvaria hamiltonii

Two known steroids, stigmasterol and 6beta-hydroxystigmasta-4,22-dien-3-one (1) and two unusual polyketides, cis-4-hydroxymellein (2) and trans-4-hydroxymellein (3) were isolated from the stem bark of Uvaria hamiltonii. The structures of the compounds were elucidated independently by high-resolution 2D-NMR techniques and confirmed by comparison with previously reported values.Dva poznata steroida, stigmasterol i 6-hidroksistigmasta-4,22-dien-3-on (1) i dva neuobičajena poliketida, cis-4-hidroksimelein (2) i trans-4-hidroksimelein (3) izolirana su iz kore biljke Uvaria hamiltonii. Strukture spojeva određene su neovisno 2D-NMR spektroskopijom visoke rezolucije i usporedbom s literaturnim podacima

Efficacy of selected anthelmintics against gastrointestinal nematodes of sheep owned by smallholder farmers in Wolaita, Southern Ethiopia

The present study was conducted to investigate the efficacy of albendazole, tetramisole and ivermectin against gastrointestinal nematodes of sheep owned by smallholder farmers. Eighty three sheep were selected for the study and divided into four groups: the first group was treated with Albendazole, the second group treated with Tetramisole, the third group with Ivermectin and the fourth group untreated to serve as control. Faecal sample were collected on day zero before treatment, and again on day 10 post treatment. The efficacy for each anthelmintic was measured using the faecal egg count reduction test. The arithmetic faecal egg count reduction for albendazole, tetramisole and ivermectin were 99.34%, 97.77%, and 98.30% respectively. Therefore, the current finding suggests that there is a good state of efficacy for all tested anthelmintics against gastrointestinal nematodes of sheep. Keywords: Anthelmintic, Faecal egg count, Nematodes, efficac

Expression of recombinant thermus aquaticus dna polymerase gene

Taq DNA polymerase derived from the extreme thermophillic microorganism, Thermus aquaticus is very useful in Polymerase Chain Reaction (PCR) in which high temperature stable Deoxyribonucleotide acid (DNA polymerase is needed in amplifying a specific DNA fragment. It is also useful in DNA sequencing. For this purpose, many techniques of cloning and expression of this enzyme were practiced to obtain a high performance enzyme. The purification methods were designed to retrieve a high enzyme yield. In this method, we have tried to express the recombinant Taq Pol I enzyme in different expression systems to select the best host for the protein expression. The host BL-21 was selected because of the additional property within it, a plysS plasmid for tighter protein expression but simpler purification method as adapted from Grimm et. al (1995). Protein expression was induced over a 12 hour period using IPTG before it was viewed in a large SDS- PAGE. There were bands along a marker indicating a complete protein expression as the weight of Taq DNA polymerase is 94 kD