title: Parasites and pathogens at honey bee mating sites, and the implications for monitoring colony health

authors: Steed, Erin Joy

abstract: Western honey bees (Apis mellifera) are an insect species of high environmental,  economic, and cultural importance due to their provision of pollination services to  cultivated and native plants and production of honey. Rapid, international dispersal of  the parasitic mite, Varroa destructor, has played a central role on colony health. The  host-parasite relationship between V. destructor and immature (brood) and adult worker honey bees has been researched extensively. However adult drone (male) honey bees  and their relationship with V. destructor has been underexplored. I used a choice test to  investigate V. destructor host preference between nurses, foragers, and drones. I  investigated the prevalence and abundance of V. destructor and pathogens at drone  congregation areas compared to apiaries to explore the role of drones and drone  congregation areas in monitoring of pests and pathogens. Varroa destructor selected  drones as hosts in equal proportion to foragers, suggesting that drones are important  phoretic hosts for the dispersal of V. destructor. I found that there was a significant  positive relationship between the V. destructor abundance at DCAs and the V.  destructor abundance at the nearest apiary. There was also a significant positive  relationship between the abundance of DWV in drones and the abundance of DWV in  colonies the nearest apiary. The abundance of DWV was found to be correlated with the  abundance of V. destructor, with more viral copies of DWV found in drones and colony  bees that had higher infestations of V. destructor. These results support the potential of  drones as agents of dispersal for V. destructor and highlights the opportunity that drone  congregation areas present for population-scale monitoring of honey bee pests and  pathogens.

text: Parasites and pathogens at honey bee mating sites, and the implications for monitoring colony health Western honey bees (Apis mellifera) are an insect species of high environmental,  economic, and cultural importance due to their provision of pollination services to  cultivated and native plants and production of honey. Rapid, international dispersal of  the parasitic mite, Varroa destructor, has played a central role on colony health. The  host-parasite relationship between V. destructor and immature (brood) and adult worker honey bees has been researched extensively. However adult drone (male) honey bees  and their relationship with V. destructor has been underexplored. I used a choice test to  investigate V. destructor host preference between nurses, foragers, and drones. I  investigated the prevalence and abundance of V. destructor and pathogens at drone  congregation areas compared to apiaries to explore the role of drones and drone  congregation areas in monitoring of pests and pathogens. Varroa destructor selected  drones as hosts in equal proportion to foragers, suggesting that drones are important  phoretic hosts for the dispersal of V. destructor. I found that there was a significant  positive relationship between the V. destructor abundance at DCAs and the V.  destructor abundance at the nearest apiary. There was also a significant positive  relationship between the abundance of DWV in drones and the abundance of DWV in  colonies the nearest apiary. The abundance of DWV was found to be correlated with the  abundance of V. destructor, with more viral copies of DWV found in drones and colony  bees that had higher infestations of V. destructor. These results support the potential of  drones as agents of dispersal for V. destructor and highlights the opportunity that drone  congregation areas present for population-scale monitoring of honey bee pests and  pathogens.

year: 2023

title: An enzymatic/acid-catalyzed hybrid process for biodiesel production from soybean oil

authors: Ting, Wei-Jia

subjects: acid catalyst

abstract: The present study is aimed at developing an enzymatic/acid-catalyzed hybrid process for biodiesel production using soybean oil as feedstock. In the enzymatic hydrolysis, 88% of the oil taken initially was hydrolyzed by binary immobilized lipase after 5 h under optimal conditions. The hydrolysate was further used in acid-catalyzed esterification for biodiesel production and the effects of temperature, catalyst concentration, feedstock to methanol molar ratio, and reaction time on biodiesel conversion were investigated. By using a feedstock to methanol molar ratio of 1:15 and a sulfuric acid concentration of 2.5%, a biodiesel conversion of 99% was obtained after 12 h of reaction at 50 °C. The biodiesel produced by this process met the American Society for Testing and Materials (ASTM) standard. This hybrid process may open a way for biodiesel production using unrefined and used oil as feedstock.

text: An enzymatic/acid-catalyzed hybrid process for biodiesel production from soybean oil The present study is aimed at developing an enzymatic/acid-catalyzed hybrid process for biodiesel production using soybean oil as feedstock. In the enzymatic hydrolysis, 88% of the oil taken initially was hydrolyzed by binary immobilized lipase after 5 h under optimal conditions. The hydrolysate was further used in acid-catalyzed esterification for biodiesel production and the effects of temperature, catalyst concentration, feedstock to methanol molar ratio, and reaction time on biodiesel conversion were investigated. By using a feedstock to methanol molar ratio of 1:15 and a sulfuric acid concentration of 2.5%, a biodiesel conversion of 99% was obtained after 12 h of reaction at 50 °C. The biodiesel produced by this process met the American Society for Testing and Materials (ASTM) standard. This hybrid process may open a way for biodiesel production using unrefined and used oil as feedstock.

year: 2008

title: The presence of the past: Maori history in contemporary reflection

authors: Mahuika, Nepia

abstract: This is the opening line of a famous saying in my tribe. For our people - Ngāti Porou - these words have become embedded in our tribal identity as important directives that we are encouraged to aspire to. In the “days destined to you”, Ngata reminds us that each generation has its own mana (or authority), our own responsibilities and challenges, our own dreams and destinies to fulfil, and our own histories to tell about Ngāti Porou: who we are, our past, present, and future. If we consider this expectant, and I think hopeful, affirmation as a gift and responsibility, then taking real ownership of the “days destined to us” requires us to know what our forebears have entrusted us with. What are those historical gifts that we might use to “centre” and assert ourselves as Māori, as Ngāti Porou? We might look at this directly, i mua: the past before us because it is our history that is so crucial to us as we walk consciously, and with determination, into the future. Our past before us helps us to know where we are going, it helps us correc our course when we stray, keeps us mindful of the “kaupapa”: whatever that might be in our generation and corner of the Maori universe. We’ve heard already today from both Enoka and Arini how Māori, in our own ways, are engaging with our past, drawing on our korero tuku iho (our oral histories passed down across the generations), on our whakairo (our carving), to illuminate the many ways Māori do, and think about, the past.

text: The presence of the past: Maori history in contemporary reflection This is the opening line of a famous saying in my tribe. For our people - Ngāti Porou - these words have become embedded in our tribal identity as important directives that we are encouraged to aspire to. In the “days destined to you”, Ngata reminds us that each generation has its own mana (or authority), our own responsibilities and challenges, our own dreams and destinies to fulfil, and our own histories to tell about Ngāti Porou: who we are, our past, present, and future. If we consider this expectant, and I think hopeful, affirmation as a gift and responsibility, then taking real ownership of the “days destined to us” requires us to know what our forebears have entrusted us with. What are those historical gifts that we might use to “centre” and assert ourselves as Māori, as Ngāti Porou? We might look at this directly, i mua: the past before us because it is our history that is so crucial to us as we walk consciously, and with determination, into the future. Our past before us helps us to know where we are going, it helps us correc our course when we stray, keeps us mindful of the “kaupapa”: whatever that might be in our generation and corner of the Maori universe. We’ve heard already today from both Enoka and Arini how Māori, in our own ways, are engaging with our past, drawing on our korero tuku iho (our oral histories passed down across the generations), on our whakairo (our carving), to illuminate the many ways Māori do, and think about, the past.

year: 2016