Plant extract efficacy on mosquito mortality: preliminary studies on the effect of Ailanthus altissima extract on adult Aedes aegypti and Culex quinquefasciatus

Abstract Due to the negative environmental impact and resistance to synthetic insecticides, the development of biological control has increased significantly over the past half century with the potential of plant extracts only recently attracting attention. The purpose of this preliminary study was to examine the potential of Ailanthus altissima extract as a botanical insecticide on adult mosquitoes. Two species of mosquitoes (Aedes aegypti and Culex quinquefasciatus) and a non-target lepidopteran species, Painted Lady butterfly (Vanessa cardui) were treated with A. altissima extract from new, mature, and senesced leaflets using serial dilutions (0, 25, 50, 75, 100%) of extract via two application methods (aerosol and sugar feeding). We found that application method and leaf age had significant effects on mosquito mortality at high concentrations. These findings indicate that while mortality was not significantly high compared to commercial products, there may be potential to use an invasive plant extract as a bio-control tool for mosquito vectors of human disease pathogens

The effects of moderate prenatal alcohol exposure on the organization of exploratory behavior by adult female rats

A large body of research has indicated that moderate Prenatal Alcohol Exposure (PAE - 60 mg/dl peak BAC) can produce impairments on cognitive processes, such as spatial learning and memory. The neurobiological basis of these impairments is poorly understood but is frequently linked to alterations in hippocampal functioning. Although the hippocampus has a central role in learning and memory, damage to the hippocampus can also produce impairments in locomotor and exploratory behaviors by rodents (reviewed in Thompson et al., 2018). Rodent exploratory behavior is organized around home bases, which serves as central points of attraction from which rats and mice organize their exploratory trips into the remaining environment. We are unaware of studies investigating the relationship between moderate prenatal alcohol exposure and exploratory behavior. Thus, in the present study, we tested adult female rats in two experiments where they were allowed to freely explore a circular open field for ~30min. Here, we report that, with respect to home base behavior, exploratory movements were largely intact in rats exposed to alcohol prenatally. Specifically, animals rapidly established home bases within 5min of the beginning of testing and the bases were established in one or two locations in the environment. They made exploratory trips away and back to the home base and made several stops at this location along with bouts of grooming behavior. The results are discussed with respect to theories of hippocampal function and the impact of moderate prenatal alcohol on spatial behavior

Black hole masses and enrichment of z ~ 6 SDSS quasars

We present sensitive near-infrared spectroscopic observations for a sample of five z ~ 6 quasars. These are amongst the most distant, currently known quasars in the universe. The spectra have been obtained using ISAAC at the VLT and include the CIV, MgII and FeII lines. We measure the FeII/MgII line ratio, as an observational proxy for the Fe/alpha element ratio. We derive a ratio of 2.7+/-0.8 for our sample, which is similar to that found for lower redshift quasars, i.e., we provide additional evidence for the lack of evolution in the FeII/MgII line ratio of quasars up to the highest redshifts. This result demonstrates that the sample quasars must have undergone a major episode of iron enrichment in less than one Gyr and star formation must have commenced at z > 8. The linewidths of the MgII and CIV lines give two estimates for the black hole masses. A third estimate is given by assuming that the quasars emit at their Eddington luminosity. The derived masses using these three methods agree well, implying that the quasars are not likely to be strongly lensed. We derive central black hole masses of 0.3-5.2 10^9 solar masses. We use the difference between the redshift of MgII (a proxy for the systemic redshift of the quasar) and the onset of the Gunn Peterson trough to derive the extent of the ionized Stromgren spheres around our target quasars. The derived physical radii are about five Mpc. Using a simple ionization model, the emission of the central quasars would need of order 10^6-10^8 year to create these cavities in a surrounding intergalactic medium with a neutral fraction between 0.1 and 1.0. As the e-folding time scale for the central accreting black hole is on the order of a few times 10^7 year, it can grow by one e-folding or less within this time span.Comment: Accepted by ApJ, 15 pages, 8 figure

Magnetic resonance imaging findings in Kenyans and South Africans with active convulsive epilepsy: an observational study

Objective: Focal epilepsy is common in low- and middle-income countries. The frequency and nature of possible underlying structural brain abnormalities have, however, not been fully assessed. Methods: We evaluated the possible structural causes of epilepsy in 331 people with epilepsy (240 from Kenya and 91 from South Africa) identified from community surveys of active convulsive epilepsy. Magnetic resonance imaging (MRI) scans were acquired on 1.5-Tesla scanners to determine the frequency and nature of any underlying lesions. We estimated the prevalence of these abnormalities using Bayesian priors (from an earlier pilot study) and observed data (from this study). We used a mixed-effect modified Poisson regression approach with the site as a random effect to determine the clinical features associated with neuropathology. Results: MRI abnormalities were found in 140 of 240 (modeled prevalence = 59%, 95% confidence interval [CI]: 53%–64%) of people with epilepsy in Kenya, and in 62 of 91 (modeled prevalence = 65%, 95% CI: 57%–73%) in South Africa, with a pooled modeled prevalence of 61% (95% CI: 56%–66%). Abnormalities were common in those with a history of adverse perinatal events (15/23 [65%, 95% CI: 43%–84%]), exposure to parasitic infections (83/120 [69%, 95% CI: 60%–77%]) and focal electroencephalographic features (97/142 [68%, 95% CI: 60%–76%]), but less frequent in individuals with generalized electroencephalographic features (44/99 [44%, 95% CI: 34%–55%]). Most abnormalities were potentially epileptogenic (167/202, 82%), of which mesial temporal sclerosis (43%) and gliosis (34%) were the most frequent. Abnormalities were associated with co-occurrence of generalized non-convulsive seizures (relative risk [RR] = 1.12, 95% CI: 1.04–1.25), lack of family history of seizures (RR = 0.91, 0.86–0.96), convulsive status epilepticus (RR = 1.14, 1.08–1.21), frequent seizures (RR = 1.12, 1.04–1.20), and reported use of anti-seizure medication (RR = 1.22, 1.18–1.26). Significance: MRI identified pathologies are common in people with epilepsy in Kenya and South Africa. Mesial temporal sclerosis, the most common abnormality, may be amenable to surgical correction. MRI may have a diagnostic value in rural Africa, but future longitudinal studies should examine the prognostic role

Effect of vessel wettability on the foamability of "ideal" surfactants and "real-world" beer heads

The ability to tailor the foaming properties of a solution by controlling its chemical composition is highly desirable and has been the subject of extensive research driven by a range of applications. However, the control of foams by varying the wettability of the foaming vessel has been less widely reported. This work investigates the effect of the wettability of the side walls of vessels used for the in situ generation of foam by shaking aqueous solutions of three different types of model surfactant systems (non-ionic, anionic and cationic surfactants) along with four different beers (Guinness Original, Banks’s Bitter, Bass No 1 and Harvest Pale). We found that hydrophilic vials increased the foamability only for the three model systems but increased foam stability for all foams except the model cationic system. We then compared stability of beer foams produced by shaking and pouring and demonstrated weak qualitative agreement between both foam methods. We also showed how wettability of the glass controls bubble nucleation for beers and champagne and used this effect to control exactly where bubbles form using simple wettability patterns

Giant negative magnetoresistance in semiconductors doped by multiply charged deep impurities

A giant negative magnetoresistance has been observed in bulk germanium doped with multiply charged deep impurities. Applying a magnetic field the resistance may decrease exponentially at any orientation of the field. A drop of the resistance as much as about 10000% has been measured at 6 T. The effect is attributed to the spin splitting of impurity ground state with a very large g-factor in the order of several tens depending on impurity.Comment: 4 pages, 4 figure

Prevalence and risk factors for active convulsive epilepsy in rural northeast South Africa

Rationale: Epilepsy is among the most common neurological disorders worldwide. However,there are few large, population-based studies of the prevalence and risk factors for epilepsy in southern Africa. Methods: From August 2008 to February 2009, as part of a multi-site study, we undertook a three-stage, population-based study, embedded within the Agincourt health and socio-demographic surveillance system, to estimate the prevalence and identify risk factors of active convulsiveepilepsy (ACE) in a rural South African population. Results: The crude prevalence of ACE, after adjusting for non-response and the sensitivity of the screening method, was 7.0/1,000 individuals (95%CI 6.4—7.6) with significant geographic hetero-geneity across the study area. Being male (OR = 2.3; 95%CI 1.6—3.2), family history of seizures(OR = 4.0; 95%CI 2.0—8.1), a sibling with seizures (OR = 7.0; 95%CI 1.6—31.7), problems after deliv-ery (OR = 5.9; 95%CI 1.2—24.6), and history of snoring (OR = 6.5; 95%CI 4.5—9.5) were significantlyassociated with ACE. For children, their mother’s exposure to some formal schooling was pro-tective (OR = 0.30; 95%CI 0.11—0.84) after controlling for age and sex. Human immunodeficiencyvirus was not found to be associated with ACE. Conclusions: ACE is less frequent in this part of rural South Africa than other parts of sub-SaharanAfrica. Improving obstetric services could prevent epilepsy. The relationship between snoring and ACE requires further investigation, as does the relative contribution of genetic and environmental factors to examine the increased risk in those with a family history of epilepsy

The Journal of Microelectronic Research 2008

https://scholarworks.rit.edu/meec_archive/1016/thumbnail.jp

Ongoing β-Cell Turnover in Adult Nonhuman Primates Is Not Adaptively Increased in Streptozotocin-Induced Diabetes

OBJECTIVE: \u3b2-Cell turnover and its potential to permit \u3b2-cell regeneration in adult primates are unknown. Our aims were 1) to measure \u3b2-cell turnover in adult nonhuman primates; 2) to establish the relative contribution of \u3b2-cell replication and formation of new \u3b2-cells from other precursors (defined thus as \u3b2-cell neogenesis); and 3) to establish whether there is an adaptive increase in \u3b2-cell formation (attempted regeneration) in streptozotocin (STZ)-induced diabetes in adult nonhuman primates. RESEARCH DESIGN AND METHODS: Adult (aged 7 years) vervet monkeys were administered STZ (45-55 mg/kg, n = 7) or saline (n = 9). Pancreas was obtained from each animal twice, first by open surgical biopsy and then by euthanasia. \u3b2-Cell turnover was evaluated by applying a mathematic model to measured replication and apoptosis rates. RESULTS: \u3b2-Cell turnover is present in adult nonhuman primates (3.3 \ub1 0.9 mg/month), mostly (~80%) derived from \u3b2-cell neogenesis. \u3b2-Cell formation was minimal in STZ-induced diabetes. Despite marked hyperglycemia, \u3b2-cell apoptosis was not increased in monkeys administered STZ. CONCLUSIONS: There is ongoing \u3b2-cell turnover in adult nonhuman primates that cannot be accounted for by \u3b2-cell replication. There is no evidence of \u3b2-cell regeneration in monkeys administered STZ. Hyperglycemia does not induce \u3b2-cell apoptosis in nonhuman primates in vivo

Influence of Total Western Diet on Docosahexaenoic Acid Suppression of Silica-Triggered Lupus Flaring in NZBWF1 Mice

Lupus is a debilitating multi-organ autoimmune disease clinically typified by periods of flare and remission. Exposing lupus-prone female NZBWF1 mice to crystalline silica (cSiO2), a known human autoimmune trigger, mimics flaring by inducing interferon-related gene (IRG) expression, inflammation, ectopic lymphoid structure (ELS) development, and autoantibody production in the lung that collectively accelerate glomerulonephritis. cSiO2-triggered flaring in this model can be prevented by supplementing mouse diet with the ω-3 polyunsaturated fatty acid (PUFA) docosahexaenoic acid (DHA). A limitation of previous studies was the use of purified diet that, although optimized for rodent health, does not reflect the high American intake of saturated fatty acid (SFA), ω-6 PUFAs, and total fat. To address this, we employed here a modified Total Western Diet (mTWD) emulating the 50th percentile U.S. macronutrient distribution to discern how DHA supplementation and/or SFA and ω-6 reduction influences cSiO2-triggered lupus flaring in female NZBWF1 mice. Six-week-old mice were fed isocaloric experimental diets for 2 wks, intranasally instilled with cSiO2 or saline vehicle weekly for 4 wks, and tissues assessed for lupus endpoints 11 wks following cSiO2 instillation. In mice fed basal mTWD, cSiO2 induced robust IRG expression, proinflammatory cytokine and chemokine elevation, leukocyte infiltration, ELS neogenesis, and autoantibody production in the lung, as well as early kidney nephritis onset compared to vehicle-treated mice fed mTWD. Consumption of mTWD containing DHA at the caloric equivalent to a human dose of 5 g/day dramatically suppressed induction of all lupus-associated endpoints. While decreasing SFA and ω-6 in mTWD modestly inhibited some disease markers, DHA addition to this diet was required for maximal protection against lupus development. Taken together, DHA supplementation at a translationally relevant dose was highly effective in preventing cSiO2-triggered lupus flaring in NZBWF1 mice, even against the background of a typical Western diet