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Articles 1891 - 1920 of 2421

Full-Text Articles in Life Sciences

Integration Of Edible Beans (Phaseolus Vulgaris L.) Into The Push-Pull Technology Developed For Stemborer And Striga Control In Maize-Based Cropping Systems, Zeyaur R. Khan, Charles A.O. Midega, Japhether M. Wanyama, David M. Amudavi, Ahmed Hassanali, Jimmy Pittchar, John A. Pickett Nov 2009

Integration Of Edible Beans (Phaseolus Vulgaris L.) Into The Push-Pull Technology Developed For Stemborer And Striga Control In Maize-Based Cropping Systems, Zeyaur R. Khan, Charles A.O. Midega, Japhether M. Wanyama, David M. Amudavi, Ahmed Hassanali, Jimmy Pittchar, John A. Pickett

All Peer-Reviewed Publications

Smallholder farming systems in eastern Africa are characterized by cereal/edible legume intercrops in fields severely constrained by parasitic weed, Striga hermonthica, cereal stemborers and declining soil fertility. The push-pull technology concurrently addresses these constraints. It involves intercropping maize with stemborer repellent fodder legume, Desmodium spp. (push), with an attractant crop, Napier grass, Pennisetum purpureum (pull), planted around this intercrop, thus making it difficult to interplant edible legumes. We assessed farmers' practice and perceptions on intercropping and willingness to integrate beans in their push-pull plots from a sample of 300 farmers in six districts in western Kenya. All the respondents traditionally …

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Fungal Entomopathogens: New Insights On Their Ecology, Fernando E. Vega, Mark S. Goettel, Meredith Blackwell, David Chandler, Mark A. Jackson, Siegfried Keller, Masanori Koike, Nguya K. Maniania, Arnulfo Monzón, Bonnie H. Ownley, Judith K. Pell, Drauzio E.N. Rangel, Helen E. Roy Nov 2009

Fungal Entomopathogens: New Insights On Their Ecology, Fernando E. Vega, Mark S. Goettel, Meredith Blackwell, David Chandler, Mark A. Jackson, Siegfried Keller, Masanori Koike, Nguya K. Maniania, Arnulfo Monzón, Bonnie H. Ownley, Judith K. Pell, Drauzio E.N. Rangel, Helen E. Roy

All Peer-Reviewed Publications

An important mechanism for insect pest control should be the use of fungal entomopathogens. Even though these organisms have been studied for more than 100 y, their effective use in the field remains elusive. Recently, however, it has been discovered that many of these entomopathogenic fungi play additional roles in nature. They are endophytes, antagonists of plant pathogens, associates with the rhizosphere, and possibly even plant growth promoting agents. These findings indicate that the ecological role of these fungi in the environment is not fully understood and limits our ability to employ them successfully for pest management. In this paper, …

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A Heteroskedastic Error Covariance Matrix Estimator Using A First-Order Conditional Autoregressive Markov Simulation For Deriving Asympotical Efficient Estimates From Ecological Sampled Anopheles Arabiensis Aquatic Habitat Covariates, Benjamin G. Jacob, Daniel A. Griffith, Ephantus J. Muturi, Erick X. Caamano, John I. Githure, Robert J. Novak Oct 2009

A Heteroskedastic Error Covariance Matrix Estimator Using A First-Order Conditional Autoregressive Markov Simulation For Deriving Asympotical Efficient Estimates From Ecological Sampled Anopheles Arabiensis Aquatic Habitat Covariates, Benjamin G. Jacob, Daniel A. Griffith, Ephantus J. Muturi, Erick X. Caamano, John I. Githure, Robert J. Novak

All Peer-Reviewed Publications

Background. Autoregressive regression coefficients for Anopheles arabiensis aquatic habitat models are usually assessed using global error techniques and are reported as error covariance matrices. A global statistic, however, will summarize error estimates from multiple habitat locations. This makes it difficult to identify where there are clusters of An. arabiensis aquatic habitats of acceptable prediction. It is therefore useful to conduct some form of spatial error analysis to detect clusters of An. arabiensis aquatic habitats based on uncertainty residuals from individual sampled habitats. In this research, a method of error estimation for spatial simulation models was demonstrated using autocorrelation indices and …

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Scared Sick? Predator-Pathogen Facilitation Enhances The Exploitation Of A Shared Resource, Ricardo A. Ramirez, W E. Snyder Oct 2009

Scared Sick? Predator-Pathogen Facilitation Enhances The Exploitation Of A Shared Resource, Ricardo A. Ramirez, W E. Snyder

Biology Faculty Publications

Resource use generally increases with greater consumer diversity, an effect often attributed to resource partitioning. Pathogens and predators are two classes of consumer that exhibit differences in ecologically important traits (e.g., size, resource acquisition strategy, foraging location) that could lead to complementary effects on shared prey/hosts. To examine this possibility, we manipulated diversity among a community of predators and pathogens that together attack an herbivorous beetle, Leptinotarsa decemlineata, and measured resulting effects on herbivore suppression and resulting plant damage. We found that herbivore mortality increased, and plant damage decreased, when more natural enemy species were present. However, closer examination revealed …

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Effect Of Self-Determination Theory-Based Strategies For Staging Recreation Encounters On Intrinsic Motivation Of Youth Residential Campers, Mark F. Roark, Gary D. Ellis Oct 2009

Effect Of Self-Determination Theory-Based Strategies For Staging Recreation Encounters On Intrinsic Motivation Of Youth Residential Campers, Mark F. Roark, Gary D. Ellis

Kinesiology and Health Science Faculty Publications

Parents and caregivers generally believe that the camp experiences they purchase for their children will not only yield transient pleasure and lasting memories of fun encounters, but significant developmental outcomes as well. Camp professionals serving over 11 million youths each year embrace such outcomes and commonly advance mission statements that point to the development of friendship skills, self-confidence, competence, self-reliance, independence, citizenship, and many other developmental outcomes. Empirical evidence of how these outcomes might be facilitated through specific recreation leadership strategies (e.g., activity staging) is lacking. The Self-Determination Theory (SDT) would suggest that youth leaders (e.g., camp counselors, recreation activity …

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Odorants That Induce Hygienic Behavior In Honeybees: Identification Of Volatile Compounds In Chalkbrood-Infected Honeybee Larvae, Jodi A.I. Swanson, Baldwyn Torto, Stephen A. Kells, Karen A. Mesce, James H. Tumlinson, Marla Spivak Oct 2009

Odorants That Induce Hygienic Behavior In Honeybees: Identification Of Volatile Compounds In Chalkbrood-Infected Honeybee Larvae, Jodi A.I. Swanson, Baldwyn Torto, Stephen A. Kells, Karen A. Mesce, James H. Tumlinson, Marla Spivak

All Peer-Reviewed Publications

Social insects that live in large colonies are vulnerable to disease transmission due to relatively high genetic relatedness among individuals and high rates of contact within and across generations. While individual insects rely on innate immune responses, groups of individuals also have evolved social immunity. Hygienic behavior, in which individual honeybees detect chemical stimuli from diseased larvae and subsequently remove the diseased brood from the nest, is one type of social immunity that reduces pathogen transmission. Three volatile compounds, collected from larvae infected with the fungal pathogen Ascosphaera apis and detected by adult honey bees, were identified by coupled gas …

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Relationship Between Virulence And Repellency Of Entomopathogenic Isolates Of Metarhizium Anisopliae And Beauveria Bassiana To The Termite Macrotermes Michaelseni, D. M. Mburu, L. Ochola, N. K. Maniania, P. G.N. Njagi, L. M. Gitonga, M. W. Ndung'u, A. K. Wanjoya, A. Hassanali Sep 2009

Relationship Between Virulence And Repellency Of Entomopathogenic Isolates Of Metarhizium Anisopliae And Beauveria Bassiana To The Termite Macrotermes Michaelseni, D. M. Mburu, L. Ochola, N. K. Maniania, P. G.N. Njagi, L. M. Gitonga, M. W. Ndung'u, A. K. Wanjoya, A. Hassanali

All Peer-Reviewed Publications

Termites encounter a diverse array of potentially useful and harmful fungi in their subterranean habitats. These vary from symbiotic to harmful species with varying levels of virulence. How these hemiedaphic insects survive in habitats with infective fungi is not well understood. Possible mediation of olfactory signals in avoiding contact with entomopathogenic fungi has been explored by a number of workers. In the present study, we initially found that Macrotermes michaelseni detected a virulent isolate of Metarhizium anisopliae from some distance and avoided direct physical contact. We hypothesized that there may be a relationship between virulence and repellency of different isolates …

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Energy Budgets Of Eared Grebes On The Great Salt Lake And Implications For Harvest Of Brine Shrimp, Michael R. Conover, Joe N. Caudell Sep 2009

Energy Budgets Of Eared Grebes On The Great Salt Lake And Implications For Harvest Of Brine Shrimp, Michael R. Conover, Joe N. Caudell

Wildland Resources Faculty Publications

About 1.5-million eared grebes (Podiceps nigricollis), representing half of the North American population, stage on Utah's Great Salt Lake, USA (GSL) during autumn migration to forage on brine shrimp (Artemia franciscana). Indirectly competing with birds for brine shrimp are commercial harvesters who annually collect >1 million kg (dry wt) of shrimp cysts (i.e., hardened eggs), an amount that during some years equals up to half of all brine shrimp cysts produced annually on the GSL. No information was available regarding what impact this commercial harvest was having on eared grebes. We determined daily energy requirements of eared grebes so that …

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Olfactory Attraction Of Egg Parasitoids To Virgin Females Of Noctuid Stemborers, Anani Yaovi Bruce, Fritz Schulthess, Jones Mueke, Paul André Calatayud Aug 2009

Olfactory Attraction Of Egg Parasitoids To Virgin Females Of Noctuid Stemborers, Anani Yaovi Bruce, Fritz Schulthess, Jones Mueke, Paul André Calatayud

All Peer-Reviewed Publications

To locate hosts, egg parasitoids rely on infochemicals of the adult host stage, e.g. pheromones, rather than cues emitted by the inconspicuous egg themselves. Here, we show that three different egg parasitoid species the scelionids Telenomus busseolae Gahan and Telenomus isis Polaszek and the trichogrammatid Trichogramma bournieri Pintureau & Babault were attracted to both calling and non-calling females of the noctuids Busseola fusca (Fuller), Sesamia calamistis (Hampson) and Sesamia nonagrioides (Lefebvre). In Y-tube olfactometer experiments this study revealed a preference of all three parasitoids for non-calling (general odors of virgin females) and calling moth (sex pheromone) over the control (clean …

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Thermal Tolerance Of The Coffee Berry Borer Hypothenemus Hampei: Predictions Of Climate Change Impact On A Tropical Insect Pest, Juliana Jaramillo, Adenirin Chabi-Olaye, Charles Kamonjo, Alvaro Jaramillo, Fernando E. Vega, Hans Michael Poehling, Christian Borgemeister Aug 2009

Thermal Tolerance Of The Coffee Berry Borer Hypothenemus Hampei: Predictions Of Climate Change Impact On A Tropical Insect Pest, Juliana Jaramillo, Adenirin Chabi-Olaye, Charles Kamonjo, Alvaro Jaramillo, Fernando E. Vega, Hans Michael Poehling, Christian Borgemeister

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Coffee is predicted to be severely affected by climate change. We determined the thermal tolerance of the coffee berry borer , Hypothenemus hampei, the most devastating pest of coffee worldwide, and make inferences on the possible effects of climate change using climatic data from Colombia, Kenya, Tanzania, and Ethiopia. For this, the effect of eight temperature regimes (15, 20, 23, 25, 27, 30, 33 and 35°C) on the bionomics of H. hampei was studied. Successful egg to adult development occurred between 20-30°C. Using linear regression and a modified Logan model, the lower and upper thresholds for development were estimated at …

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A Randomized Cross-Over Study Of The Quality Of Cardiopulmonary Resuscitation Among Females Performing 30:2 And Hands-Only Cardiopulmonary Resuscitation, Cynthia Trowbridge, Jesal N. Parekh, Mark D. Ricard, Jerald Potts, W Clive Patrickson, Carolyn Cason Jul 2009

A Randomized Cross-Over Study Of The Quality Of Cardiopulmonary Resuscitation Among Females Performing 30:2 And Hands-Only Cardiopulmonary Resuscitation, Cynthia Trowbridge, Jesal N. Parekh, Mark D. Ricard, Jerald Potts, W Clive Patrickson, Carolyn Cason

Kinesiology Faculty Publications & Presentations - Archive

Background: Hands-Only cardiopulmonary resuscitation (CPR) is recommended for use on adult victims of witnessed out-of-hospital (OOH) sudden cardiac arrest or in instances where rescuers cannot perform ventilations while maintaining minimally interrupted quality compressions. Promotion of Hands-Only CPR should improve the incidence of bystander CPR and, subsequently, survival from OOH cardiac arrest; but, little is known about a rescuer's ability to deliver continuous chest compressions of adequate rate and depth for periods typical of emergency services response time. This study evaluated chest compression rate and depth as subjects performed Hands-Only CPR for 10 minutes. For comparison purposes, each also performed chest …

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Recilia Banda Kramer (Hemiptera: Cicadellidae), A Vector Of Napier Stunt Phytoplasma In Kenya, Evans Obura, Charles A.O. Midega, Daniel Masiga, John A. Pickett, Mohamed Hassan, Shinsaku Koji, Zeyaur R. Khan Jul 2009

Recilia Banda Kramer (Hemiptera: Cicadellidae), A Vector Of Napier Stunt Phytoplasma In Kenya, Evans Obura, Charles A.O. Midega, Daniel Masiga, John A. Pickett, Mohamed Hassan, Shinsaku Koji, Zeyaur R. Khan

All Peer-Reviewed Publications

Napier grass (Pennisetum purpureum) is the most important fodder crop in smallholder dairy production systems in East Africa, characterized by small zero-grazing units. It is also an important trap crop used in the management of cereal stemborers in maize in the region. However, production of Napier grass in the region is severely constrained by Napier stunt disease. The etiology of the disease is known to be a phytoplasma, 16SrXI strain. However, the putative insect vector was yet unknown. We sampled and identified five leafhopper and three planthopper species associated with Napier grass and used them as candidates in pathogen transmission …

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Anti-Mosquito And Antimicrobial Nor-Halimanoids, Isocoumarins And An Anilinoid From Tessmannia Densiflora, Charles Kihampa, Mayunga H.H. Nkunya, Cosam C. Joseph, Stephen M. Magesa, Ahmed Hassanali, Matthias Heydenreich, Erich Kleinpeter Jul 2009

Anti-Mosquito And Antimicrobial Nor-Halimanoids, Isocoumarins And An Anilinoid From Tessmannia Densiflora, Charles Kihampa, Mayunga H.H. Nkunya, Cosam C. Joseph, Stephen M. Magesa, Ahmed Hassanali, Matthias Heydenreich, Erich Kleinpeter

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The nor-halimane diterpenoid tessmannic acid and its methyl, 2-methylisopropyl and 1-methylbutyl esters, the unusual isocoumarins 8-hydroxy-6-methoxy-3-pentylisocoumarin and 7-chloro-8-hydroxy-6-methoxy-3-pentylisocoumarin, and 5-pentyl-3-methoxy-N-butylaniline were isolated from the stem and root bark extracts of Tessmannia densiflora Harms (Caesalpiniaceae) that showed mosquito larvicidal activity. The structures were determined on interpretation of spectroscopic data. Tessmannic acid and its methyl ester exhibited antibacterial and antifungal activity. The compounds also caused high larvae and adult Anopheles gambiae mosquitoe mortality effects, and stronger mosquito repellency than that shown by the standard repellent DEET, hence indicating Tessmannia species to be potential sources of bioactive natural products. © 2009 Elsevier Ltd. …

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Collective Batesian Mimicry Of Ant Groups By Aggregating Spiders, Ximena J. Nelson, Robert R. Jackson Jul 2009

Collective Batesian Mimicry Of Ant Groups By Aggregating Spiders, Ximena J. Nelson, Robert R. Jackson

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Many predators are averse to attacking ants and many palatable arthropods are Batesian mimics of ants. We considered whether aggregating Batesian mimics of ants can become more repelling to ant-averse predators by, as a group, resembling groups of ants (collective mimicry). Myrmarachne melanotarsa is a gregarious ant-like jumping spider (Salticidae) that resembles and associates with the ant Crematogaster sp. We used three large ant-averse salticids as predators in experiments. Besides M. melanotarsa and Crematogaster we used midges (Chaoborus sp.) and a small nonant-like, but gregarious, salticid (Menemerus sp.) as prey. The predators readily attacked both live midges and the nonant-like …

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Predation And Reproductive Output Of The Ladybird Beetle Stethorus Tridens Preying On Tomato Red Spider Mite Tetranychus Evansi, Erika P.J. Britto, Manoel G.C. Gondim, Jorge B. Torres, Komi K.M. Fiaboe, Gilberto J. Moraes, Markus Knapp Jun 2009

Predation And Reproductive Output Of The Ladybird Beetle Stethorus Tridens Preying On Tomato Red Spider Mite Tetranychus Evansi, Erika P.J. Britto, Manoel G.C. Gondim, Jorge B. Torres, Komi K.M. Fiaboe, Gilberto J. Moraes, Markus Knapp

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Predatory behaviour and reproductive output of the ladybird beetle Stethorus tridens Gordon as function of the tomato red spider mite (TRSM), Tetranychus evansi Baker & Pritchard, densities was investigated in the laboratory. Adult female of S. tridens were isolated in cylindrical plastic arenas, containing a leaf disc of Solanum americanum Mill. with 5, 20, 40, 60, 80 or 100 T. evansi nymphs. The number of prey consumed and eggs laid were evaluated daily for ten consecutive days, starting at the oviposition. Oviposition of S. tridens was positively correlated with prey consumption and lower threshold prey consumption for S. tridens laying …

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Concentrations Of Selenium And Mercury In Eared Grebes (Podiceps Nigricollis) From Utah’S Great Salt Lake, Usa, Michael R. Conover, Josh L. Vest Jun 2009

Concentrations Of Selenium And Mercury In Eared Grebes (Podiceps Nigricollis) From Utah’S Great Salt Lake, Usa, Michael R. Conover, Josh L. Vest

Wildland Resources Faculty Publications

We examined selenium and mercury concentrations in eared grebes (Podiceps nigricollis) that spent the fall of 2006 on the Great Salt Lake (UT, USA), where their diet consisted mainly of brine shrimp (Artemia franciscana). Selenium concentrations in livers varied based on when the grebes were collected (lower in September [mean ± standard error, 9.4 ± 0.7 μg/g dry wt] than in November [14.5 ± 1.4 μg/g]), on where the birds were collected on the Great Salt Lake (Antelope Island, 8.6 ± 0.5 μg/g; Stansbury Island, 15.2 ± 1.4 μg/g), and on the grebe's age (juveniles, 8.5 ± 1.5 μg/g; adults, …

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White Lupin Leads To Increased Maize Yield Through A Soil Fertility-Independent Mechanism: A New Candidate For Fighting Striga Hermonthica Infestation?, Laure Weisskopf, Pollycarp Akello, Roxane Milleret, Zeyaur R. Khan, Fritz Schulthess, Jean Michel Gobat, Renée Claire Le Bayon Jun 2009

White Lupin Leads To Increased Maize Yield Through A Soil Fertility-Independent Mechanism: A New Candidate For Fighting Striga Hermonthica Infestation?, Laure Weisskopf, Pollycarp Akello, Roxane Milleret, Zeyaur R. Khan, Fritz Schulthess, Jean Michel Gobat, Renée Claire Le Bayon

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Nitrogen (N)-deficiency and lack of phosphorus (P) availability are major constraints to maize yields in Western Kenya. In a two-season field study in the lake Victoria basin, we tested the capacity of white lupin (Lupinus albus (L.), cv. Ultra), as a nitrogen-fixing crop with a highly efficient P-acquisition capacity, to increase maize yields when used as a companion or cover crop, or as a source of organic matter. Each experiment was performed on three different fields (Vertisols) differing in N/P availability, previous cropping history and in levels of infestation by the parasitic weed Striga hermonthica (Del.) Benth. Our results show …

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Where To Sample? Ecological Implications Of Sampling Strata In Determining Abundance And Impact Of Natural Enemies Of The Coffee Berry Borer, Hypothenemus Hampei, Juliana Jaramillo, Adenirin Chabi-Olaye, Christian Borgemeister, Charles Kamonjo, Hans Michael Poehling, Fernando E. Vega Jun 2009

Where To Sample? Ecological Implications Of Sampling Strata In Determining Abundance And Impact Of Natural Enemies Of The Coffee Berry Borer, Hypothenemus Hampei, Juliana Jaramillo, Adenirin Chabi-Olaye, Christian Borgemeister, Charles Kamonjo, Hans Michael Poehling, Fernando E. Vega

All Peer-Reviewed Publications

Several parasitoids of African origin have been introduced to coffee producing areas of the Americas and Asia as biological control agents of the coffee berry borer (CBB) Hypothenemus hampei (Coleoptera: Curculionidae). These parasitoids have become established in the field but their effect on the CBB has been limited. A two-year field study in Western Kenya has found Prorops nasuta (Hymenoptera: Bethylidae) to be the predominant parasitoid emerging from CBB-infested coffee berries collected on coffee trees or from the ground. P. nasuta comprises more than 75% of the total natural enemies collected. The density of P. nasuta was 90% higher in …

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Diversity, Distribution And Role Of Wild Crucifers In Major Cabbage And Kale Growing Areas Of Kenya, R. Kahuthia-Gathu, B. Löhr, H. M. Poehling, P. K. Mbugua Jun 2009

Diversity, Distribution And Role Of Wild Crucifers In Major Cabbage And Kale Growing Areas Of Kenya, R. Kahuthia-Gathu, B. Löhr, H. M. Poehling, P. K. Mbugua

All Peer-Reviewed Publications

An investigation of the diversity and distribution of wild crucifer species and their importance for cultivated crucifers was conducted during 2005 and 2006 in the highland and mid-altitude semi-arid areas of Kenya. Thirteen species of wild crucifers in nine genera were recorded: Raphanus raphanistrum, Erucastrum arabicum, Sisymbrium officinale, Crambe kilimandscharica, Capsella bursa-pastoris, Rorippa nudiuscula, Ro. micrantha, Ro. microphylla, Lepidium bonariense, Coronopus didymus, Brassica rapa, B. juncea and an unidentified Brassica species. Highland areas had significantly higher species diversity and species richness than mid-altitude semi-arid areas. Species richness, diversity and evenness varied with season and location. Raphanus raphanistrum was the dominant …

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Prospects For Developing Odour Baits To Control Glossina Fuscipes Spp., The Major Vector Of Human African Trypanosomiasis, Maurice O. Omolo, Ahmed Hassanali, Serge Mpiana, Johan Esterhuizen, Jenny Lindh, Mike J. Lehane, Philippe Solano, Jean Baptiste Rayaisse, Glyn A. Vale, Steve J. Torr, Inaki Tirados May 2009

Prospects For Developing Odour Baits To Control Glossina Fuscipes Spp., The Major Vector Of Human African Trypanosomiasis, Maurice O. Omolo, Ahmed Hassanali, Serge Mpiana, Johan Esterhuizen, Jenny Lindh, Mike J. Lehane, Philippe Solano, Jean Baptiste Rayaisse, Glyn A. Vale, Steve J. Torr, Inaki Tirados

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We are attempting to develop cost-effective control methods for the important vector of sleeping sickness, Glossina fuscipes spp. Responses of the tsetse flies Glossina fuscipes fuscipes (in Kenya) and G. f. quanzensis (in Democratic Republic of Congo) to natural host odours are reported. Arrangements of electric nets were used to assess the effect of cattle-, human- and pig-odour on (1) the numbers of tsetse attracted to the odour source and (2) the proportion of flies that landed on a black target (1 × 1 m). In addition responses to monitor lizard (Varanus niloticus) were assessed in Kenya. The effects of …

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Bed Net Use And Associated Factors In A Rice Farming Community In Central Kenya, Peter N. Ng'ang'a, Gayathri Jayasinghe, Violet Kimani, Josephat Shililu, Charity Kabutha, Lucy Kabuage, John Githure, Clifford Mutero May 2009

Bed Net Use And Associated Factors In A Rice Farming Community In Central Kenya, Peter N. Ng'ang'a, Gayathri Jayasinghe, Violet Kimani, Josephat Shililu, Charity Kabutha, Lucy Kabuage, John Githure, Clifford Mutero

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Background. Use of insecticide-treated nets (ITNs) continues to offer potential strategy for malaria prevention in endemic areas. However their effectiveness, sustainability and massive scale up remain a factor of socio-economic and cultural variables of the local community which are indispensable during design and implementation stages. Methods. An ethnographic household survey was conducted in four study villages which were purposefully selected to represent socio-economic and geographical diversity. In total, 400 households were randomly selected from the four study villages. Quantitative and qualitative information of the respondents were collected by use of semi-structured questionnaires and focus group discussions. Results. Malaria was reported …

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Fortification Of Reduced Fat Cheddar Cheese With N-3 Fatty Acids: Effect On Off-Flavor Generation, Silvana Martini, J. E. Thurgood, C. Brothersen, Robert E. Ward, D. J. Mcmahon May 2009

Fortification Of Reduced Fat Cheddar Cheese With N-3 Fatty Acids: Effect On Off-Flavor Generation, Silvana Martini, J. E. Thurgood, C. Brothersen, Robert E. Ward, D. J. Mcmahon

Nutrition, Dietetics, and Food Sciences Faculty Publications

The objective of this study was to fortify 50% reduced fat Cheddar cheese with n-3 fatty acids and evaluate whether this fortification generated specific off-flavors in the cheese. Docosahexaenoic (DHA) and eicosapentaenoic (EPA) fatty acids were added to the cheese to obtain 3 final fortification levels [18, 35, and 71mg of DHA/EPA per serving size (28g) of cheese] representing 10, 20, and 40% of the suggested daily intake level for DHA/EPA. The presence of oxidized, rancid, and fishy flavors as a function of fortification level and cheese aging (6 mo) was evaluated using a sensory descriptive panel. No differences were …

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Mate-Odour Identification By Both Sexes Of Evarcha Culicivora, An East African Jumping Spider, Fiona R. Cross, Robert R. Jackson May 2009

Mate-Odour Identification By Both Sexes Of Evarcha Culicivora, An East African Jumping Spider, Fiona R. Cross, Robert R. Jackson

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Evarcha culicivora is an unusual salticid spider because each sex actively courts the other and both sexes make distinctive mate-choice decisions. Here we use olfactometer experiments for investigating the ability of each sex to identify potential mates on the basis of odour alone. Test spiders spent more time in the vicinity of opposite-sex conspecific source spiders, regardless of whether or not these source spiders had previously mated, when the alternatives were conspecific individuals of the same sex, juveniles or a control (no odour source). This trend held regardless of the test spider's and source spider's age after reaching maturity and, …

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Variability In Pheromone Communication Among Different Haplotype Populations Of Busseola Fusca, A. E. Félix, G. Genestier, C. Malosse, P. A. Calatayud, B. Le Rü, J. F. Silvain, B. Frérot May 2009

Variability In Pheromone Communication Among Different Haplotype Populations Of Busseola Fusca, A. E. Félix, G. Genestier, C. Malosse, P. A. Calatayud, B. Le Rü, J. F. Silvain, B. Frérot

All Peer-Reviewed Publications

The relationship between pheromone composition and mitochondrial haplotype clades was investigated by coupling DNA analyses with pheromone identification and male mate searching behavior among different geographic populations of Busseola fusca. The within-population variations in pheromone blend were as great as those observed between geographic populations, suggesting that the female sex pheromone blend was not the basis of reproductive isolation between the geographic clades. Furthermore, while data from wind tunnel experiments demonstrated that most of the tested males were sensitive to small variations in pheromone mixture, there was considerable within-population variability in the observed response. The study identified a new pheromone …

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Increasing Omega Fatty Acid Content In Milk Through Cow’S Diet: Effect On Milk Flavor, K. A. S. Nelson, Silvana Martini Apr 2009

Increasing Omega Fatty Acid Content In Milk Through Cow’S Diet: Effect On Milk Flavor, K. A. S. Nelson, Silvana Martini

Nutrition, Dietetics, and Food Sciences Faculty Publications

Milk with an increased content of eicosapentaenoic acid (EPA), docosahexaenoic acid (DHA), and conjugated linoleic acid (CLA) was obtained by incorporating fish oil into the feed of cows. The 4 feed treatments used were a control diet of 57% forage and 43% concentrate mix with EnerGII fat supplement at 1.65% of dietary DM, or EnerGII in the basal diet was partially replaced with 1) 0.21% partially ruminally inert calcium salts of 71% fish oil given at 0.41% of DM; 2) 0.41% inert calcium salts of 71% fish oil given at 0.83% of DM; or 3) 0.83% inert calcium salts of …

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Evaluation Of Farmers' Field Days As A Dissemination Tool For Push-Pull Technology In Western Kenya, David M. Amudavi, Zeyaur R. Khan, Japhether M. Wanyama, Charles A.O. Midega, Jimmy Pittchar, Ahmed Hassanali, John A. Pickett Mar 2009

Evaluation Of Farmers' Field Days As A Dissemination Tool For Push-Pull Technology In Western Kenya, David M. Amudavi, Zeyaur R. Khan, Japhether M. Wanyama, Charles A.O. Midega, Jimmy Pittchar, Ahmed Hassanali, John A. Pickett

All Peer-Reviewed Publications

Our earlier study on farmers' adoption of 'Push-pull' technology (PPT) for management of cereal stemborers and Striga weed showed that field days (FDs) could be effective in technology dissemination. Hence, in an effort to utilize effective and economical dissemination strategies, we undertook a detailed study in 2007 to assess their effectiveness in PPT dissemination by interviewing 1492 participants randomly selected during participation in FDs. A majority (80%) of the respondents learnt about the biology and damage caused by stemborers and Striga, how PPT works, how to implement PPT and utilize its products, among others. Consequently, over 70% of them favoured …

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Spatiotemporal Dynamics Of Immature Culicines (Subfamily Culicinae) And Their Larval Habitats In Mwea Rice Scheme, Kenya, Ephantus J. Muturi, Joseph M. Mwangangi, Benjamin G. Jacob, Josephat I. Shililu, Charles M. Mbogo, John I. Githure, Robert J. Novak Mar 2009

Spatiotemporal Dynamics Of Immature Culicines (Subfamily Culicinae) And Their Larval Habitats In Mwea Rice Scheme, Kenya, Ephantus J. Muturi, Joseph M. Mwangangi, Benjamin G. Jacob, Josephat I. Shililu, Charles M. Mbogo, John I. Githure, Robert J. Novak

All Peer-Reviewed Publications

An ecological study was conducted at three study sites in Mwea Rice Scheme, Kenya to identify the diverse aquatic habitats in which culicine mosquitoes thrived and to explore the best strategies for mosquito control in the area. During the 11-month study period, ten habitat categories and 11 culicine species mainly dominated by Culex quinquefasciatus (72.0%) and Culex annulioris (17.9%) were identified from pupae and late instars larval samples. Two of the 11 culicine species, Ficalbia (Mimomyia) plumosa and Uranotaenia spp., have not been reported previously in the study area. Rurumi had more habitat types than either of the other study …

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Submicroscopic Gametocytes And The Transmission Of Antifolate-Resistant Plasmodium Falciparum In Western Kenya, Mayke J.A.M. Oesterholt, Michael Alifrangis, Colin J. Sutherland, Sabah A. Omar, Patrick Sawa, Christina Howitt, Louis C. Gouagna, Robert W. Sauerwein, Teun Bousema Feb 2009

Submicroscopic Gametocytes And The Transmission Of Antifolate-Resistant Plasmodium Falciparum In Western Kenya, Mayke J.A.M. Oesterholt, Michael Alifrangis, Colin J. Sutherland, Sabah A. Omar, Patrick Sawa, Christina Howitt, Louis C. Gouagna, Robert W. Sauerwein, Teun Bousema

All Peer-Reviewed Publications

Background: Single nucleotide polymorphisms (SNPs) in the dhfr and dhps genes are associated with sulphadoxine-pyrimethamine (SP) treatment failure and gametocyte carriage. This may result in enhanced transmission of mutant malaria parasites, as previously shown for chloroquine resistant parasites. In the present study, we determine the association between parasite mutations, submicroscopic P. falciparum gametocytemia and malaria transmission to mosquitoes. Methodology/Principal Findings: Samples from children treated with SP alone or in combination with artesunate (AS) or amodiaquine were genotyped for SNPs in the dhfr and dhps genes. Gametocytemia was determined by microscopy and Pfs25 RNA-based quantitative nucleic acid sequence-based amplification (Pfs25 QT-NASBA). …

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Selenium And Mercury Concentrations In California Gulls Breeding On The Great Salt Lake, Utah, Usa, Michael R. Conover, Josh L. Vest Feb 2009

Selenium And Mercury Concentrations In California Gulls Breeding On The Great Salt Lake, Utah, Usa, Michael R. Conover, Josh L. Vest

Wildland Resources Faculty Publications

We examined selenium (Se) and mercury (Hg) concentrations in adult California gulls (Larus californicus) nesting on the Great Salt Lake, Utah, USA, during 2006 and 2007. During 2006, the mean Se concentration (± standard error) was 18.1 ± 1.5 μg/g in blood on a dry-weight basis and 8.1 ± 0.4 μg/g in liver. During 2007, Se concentrations were 15.7 ± 1.5 μg/g in blood and 8.3 ± 0.4 μg/g in liver; Hg concentrations were 2.4 ± 0.3 μg/g in blood and 4.1 ± 0.5 μg/g in liver. Gulls collected from a freshwater colony located within the watershed of the Great …

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Do Sharp-Tailed Grouse Select Loafing Sites To Avoid Visual Or Olfactory Predators?, Michael R. Conover, Jennifer S. Borgo Feb 2009

Do Sharp-Tailed Grouse Select Loafing Sites To Avoid Visual Or Olfactory Predators?, Michael R. Conover, Jennifer S. Borgo

Wildland Resources Faculty Publications

Grouse should seek loafing sites hidden from predators; however, good hiding sites from predators that use vision to locate prey differ from good hiding sites from predators that use odor to locate prey. We compared characteristics of control sites to sites used for loafing by sharp-tailed grouse (Tympanuchus phasianellus) to determine whether selection of loafing sites was more influenced by the need to hide from visual or olfactory predators. Sites used for loafing were similar to control sites in characteristics that would help hide a grouse from visual predators (i.e., visual obstruction, lateral visibility, visual obstruction, cover ht, and surface …

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