852 research outputs found
Survey and analysis of the usefulness of the social studies guide for New Hampshire elementary schools
Thesis (Ed.M.)--Boston Universit
Host-parasitoid interactions of Eldana Saccharina (Lepidoptera: Pyralidae) in Cyperus Papyrus.
Thesis (Ph.D.)-University of Natal, Pietermaritzburg, 1994.Since becoming a pest in graminaceous crops in Africa, the African sugarcane
stalkborer Eldana saccharina Walker has been the subject of much study. Its
very cryptic habits have precluded more commonly available control measures
being used against it. Biological control is regarded as a viable control option,
but the apparent paucity of parasitoids in graminaceous crops leads to E.
saccharina being regarded as lacking parasitoids, and thus not a good candidate
for biological control in the classical sense. In contrast, this project argues that
interactions in indigenous hosts of E. saccharina had been ignored, and that
classical biocontrol principles and basic ecological theory could be applied by the
discovery, collection and introduction of parasitoids from its indigenous habitat
to its newly adapted habitat, sugarcane.
The habitat offered by Cyperus papyrus L. was shown to be heterogenous both
temporarily and spatially. Umbels, from young through mature to senescent,
were available in the same proportion for colonisation throughout the year.
Umbels with sexual reproductive stages (seeds) were present from early spring
into late summer, and provided an additional component to the already
heterogenous environment. Young umbels, in addition, developed from rhizomes
in an environment regarded as sub-optimal for photosynthesis, until they reached
the canopy.
All stages of umbels were attacked by E. saccharina, but larvae were only found
in rays of umbels and in the apex of the culm, which was the meristematic area
for rays, both high nutrient areas. Young umbels were never found with borer
pupae, only smaller larvae, indicating that E. saccharina development matched
growth of young umbels until they reached canopy height. Also, the majority of
borings found were occupied, indicating that infestation of young umbels was
recent. All stages of E. saccharina development were found in mature umbels,
which were also most abundant at anyone time. Numerous empty borings were
found in addition to those occupied, indicative of past occupation by E. saccharina. Very few young larvae were found in old umbels, the majority of life
stages found being pupae or empty pupal cases, and also many empty borings,
showing that old umbels were not suitable for E. saccharina development.
A guild of parasitoids which comprised Orgilus bifasciatus Turner, the most
common parasitoid of small and smaller medium E. saccharina larvae, Goniozus
indicus Ashmead the most common parasitoid of larger medium and large larvae,
and an entomogenous fungus Seauveria bassiana (Sals.) Vuill. attacking all life
stages of E. saccharina was found. Three uncommon parasitoids of smaller
saccharina were also found, viz. Sassus sublevis (Granger), Iphiaulax sp. and
Venturia sp. The former three natural enemies were instrumental in depressing
a major outbreak within two months of it being observed and then maintaining
the host population at a lower level in C. papyrus. G. indicus and B. bassiana
were most effective during the summer and autumn months, and O. bifasciatus
most effective during the winter months.
This study supports the hypotheses that the apparent paucity of parasitoids and
lack of biological control success thus far against E. saccharina in sugarcane has
been because very little was known about its ecology and biology in its
numerous indigenous host plants, and that studies of the latter factors coupled
with ecological theory could enhance biological control programmes against this
borer. As more indigenous host plants are investigated in the same way as has
been done with C. papyrus, more will become known of natural enemies of E.
saccharina. Parasitoid guilds could be selected, even from rare parasitoids in the
more stable indigenous habitats, which would provide control in the unstable
habitat of sugarcane
Use of Recommended Laboratory Testing Methods Among Patients with Tuberculosis in California
This study assessed the extent to which laboratory methods recommended by the Centers for Disease Control and Prevention were used in tuberculosis testing of patients in California in 1998. While recommended methods were used for most patients, there was room for improvement by hospital and independent non-health maintenance organization laboratories
Book Reviews
Book reviews by Charles S. Desmond, James F. Thornburg, Edward J. Gray, Walter H. E. Jaeger, and Thomas L. Shaffer
Chemical profile and in vivo toxicity evaluation of unripe Citrus aurantifolia essential oil
Citrus aurantifolia (Christm.) Swingle (syn. C. MEDICA var. ACIDA Brandis) (family: Rutaceae) essential oil is one of the cheapest oils found in local markets. Although, it is generally accepted as non-toxic to vital organs and cells, majority of people are cynical about it usage. Herein, the present study reports the chemical composition and in vivo oral toxicity study of unripe C. aurantifolia essential oil found in Ghana. The toxicity of C. aurantifolia essential oil extract was investigated via oral administration using two methods: The acute toxicity single dose study (SDS) and the repeated dose method. The oil exhibited no acute toxicity but in the sub-chronic studies, the effects was dose and time-dependent. Chemical profile investigation of the oil showed 9 constituent of phytochemicals (Germacrene isomers (61.2%), Pineen (14%), Linalool dimmer (2.9%), Bornane (11%), Citral (2.9%), Anethole (1.5%), Anisole (1.1%), Safrole (0.3%) and Demitol (0.6%)). Histopathological studies revealed conditions such as necrosis, edema and inflammatory reaction in the liver, spleen and kidneys. Marginal upsurge of biochemical parameters above normal and elevated levels of lymphocytes (35.20–46.40 g/dL) demonstrated mild toxicity among the 100 mg/kg and 500 mg/kg dose groups at the sub-chronic stage. Low levels of hemoglobin (13.60 to 12.70 g/dL), MCV (34.20–24.0 fL), MCH (40.20–36.40 g/dL) along with high levels of liver enzymes confirmed the mild toxicity of the oil at sub-chronic stage. These results demonstrate that, despite consideration of lime essential oil as safe, it can have mild hematotoxic, nephrotoxic and hepatotoxic effects
Mycobacteria in Nail Salon Whirlpool Footbaths, California
In 2000, an outbreak of Mycobacterium fortuitum furunculosis affected customers using whirlpool footbaths at a nail salon. We swabbed 30 footbaths in 18 nail salons from 5 California counties and found mycobacteria in 29 (97%); M. fortuitum was the most common. Mycobacteria may pose an infectious risk for pedicure customers
A Study of the Relationship between Food Group Recommendations and Perceived Stress: Findings from Black Women in the Deep South
Black women in the Deep South experience excess morbidity/mortality from obesity-related diseases, which may be partially attributable to poor diet. One reason for poor dietary intake may be high stress, which has been associated with unhealthy diets in other groups. Limited data are available regarding dietary patterns of black women in the Deep South and to our knowledge no studies have been published exploring relationships between stress and dietary patterns among this group. This cross-sectional study explored the relationship between stress and adherence to food group recommendations among black women in the Deep South. Participants (n=355) provided demographic, anthropometric, stress (PSS-10), and dietary (NCI ASA-24 hour recall) data. Participants were obese (BMI = 36.5 kg/m2) and reported moderate stress (PSS-10 score = 16) and minimal adherence to Dietary Guidelines for Americans food group recommendations (1/3 did not meet recommendations for any food group). Participants reporting higher stress had higher BMIs than those reporting lower stress. There was no observed relationship between stress and dietary intake in this sample. Based on these study findings, which are limited by potential misreporting of dietary intake and limited variability in stress measure outcomes, there is insufficient evidence to support a relationship between stress and dietary intake
Quality-of-Life Impact of an Investigational Subunit-Adjuvanted Herpes Zoster Vaccine in Adults ≥50 Years of Age
n/
Urban health nexus with coronavirus disease 2019 (COVID-19) preparedness and response in Africa:Rapid scoping review of the early evidence
Introduction:Severe acute respiratory syndrome coronavirus 2 also called coronavirus disease 2019 was first reported in the African continent on 14 February 2020 in Egypt. As at 18 December 2020, the continent reported 2,449,754 confirmed cases, 57,817 deaths and 2,073,214 recoveries. Urban cities in Africa have particularly suffered the brunt of coronavirus disease 2019 coupled with criticisms that the response strategies have largely been a ‘one-size-fits-all’ approach. This article reviewed early evidence on urban health nexus with coronavirus disease 2019 preparedness and response in Africa.Methods:A rapid scoping review of empirical and grey literature was done using data sources such as ScienceDirect, GoogleScholar, PubMed, HINARI and official websites of World Health Organization and Africa Centres for Disease Control and Prevention. A total of 26 full articles (empirical studies, reviews and commentaries) were synthesised and analysed qualitatively based on predefined inclusion criteria on publication relevance and quality.Results:Over 70% of the 26 articles reported on coronavirus disease 2019 response strategies across Africa; 27% of the articles reported on preparedness towards coronavirus disease 2019, while 38% reported on urbanisation nexus with coronavirus disease 2019; 40% of the publications were full-text empirical studies, while the remaining 60% were either commentaries, reviews or editorials. It was found that urban cities remain epicentres of coronavirus disease 2019 in Africa. Even though some successes have been recorded in Africa regarding coronavirus disease 2019 fight, the continent’s response strategies were largely found to be a ‘one-size-fits-all’ approach. Consequently, adoption of ‘Western elitist’ mitigating measures for coronavirus disease 2019 containment resulted in excesses and spillover effects on individuals, families and economies in Africa.Conclusion:Africa needs to increase commitment to health systems strengthening through context-specific interventions and prioritisation of pandemic preparedness over response. Likewise, improved economic resilience and proper urban planning will help African countries to respond better to future public health emergencies, as coronavirus disease 2019 cases continue to surge on the continent
- …