Thesis (M.A.)--University of Hong Kong, 1999. / Includes bibliographical references. Also available in print.

Master of Science / Department of Entomology / Thomas W. Phillips / Resistance of stored-grain insects to the fumigant gas phosphine is becoming common, due to genetic-based resistance. Using proper resistance management, phosphine can continue to be effective with efficient monitoring methods. This thesis focuses on assessing the levels of phosphine resistance across North America in a common stored-product pest, the red flour beetle, Tribolium castaneum (Herbst), and on refining a rapid bioassay method so that resistance can be easily and accurately detected. Previous work found that phosphine resistance was present in two regions of the USA, the Southeast and Midwest. In this study a discriminating-dose bioassay was used with adult beetles to determine the number of resistant and susceptible individuals in a test population. Adult T. castaneum from 25 locations across the United States and Canada were collected, and 25-60 adults from each population were assessed for the percentage of resistant individuals. Thirteen populations were deemed susceptible with no resistant insects in the samples, while eight populations had 52% or fewer individuals scored as resistant, and four populations had between 88 and 100% resistant individuals. Dose-mortality experiments were conducted to characterize the “strength” of resistance. One population with 41% resistant beetles in the discriminating dose assay was 4.5-fold resistant relative to the susceptible laboratory strain, compared to 127-fold resistant for a population with all 100% scored as resistant. Adult beetles from twelve populations were used to determine if a “knockdown” test of insects exposed to a high concentration of phosphine (3000 ppm) could assess resistance as well as the discriminating-dose mortality assay. The time required for five out of ten beetles to be knocked down, called the KT[subscript]50 for the time to knockdown 50% of the sample, was useful to characterize resistance. Phosphine susceptible beetles had KT[subscript]50 values less than 15 minutes, while samples from resistant populations had KT[subscript]50’s between 15 and 52 minutes. The refined quick test and knowledge of current levels of phosphine resistance in the United States and Canada reported in this thesis point to the importance of such information in developing phosphine resistance management programs for grain insects.

Doctor of Philosophy / Department of Entomology / Thomas W. Phillips / The phase-out of methyl bromide production, the most effective fumigant for the control of the ham mite, Tyrophagus putrescentiae (Schrank) (Acari: Acaridae), on dry-cured ham has necessitated the search for other management methods. The foundation of a successful management program is an effective monitoring program that provides information on pest presence and abundance over time and space to help in making management decisions. By using the standard trap made from disposable Petri dishes and a dog food-based bait, mite activity was monitored weekly in five dry-cured ham aging rooms from three commercial processing facilities from June 2012 to September 2013. Results indicated that mite numbers in traps in facilities typically had a pattern of sharp decline after fumigation, followed by a steady increase until the next fumigation. Average trap captures varied due to trap location, indicating that traps could be used to identify locations where mite infestation of hams may be more likely to occur. Experiments were also conducted in 6 m x 3 m climate-controlled rooms to determine the effects of some physical factors on trap capture. Factors such as trap design, trap location, trap distance, duration of trapping, and light conditions had significant effects on mite capture. Mites also responded differently to light emitting diodes of different wavelengths, either as a component of the standard trap or as a stand-alone stimulus to orientation. To determine the relationship between trap capture and mite density, experiments were carried out in the climate-controlled rooms. Mite density was varied but trap number remained constant for all mite densities. There was strong positive correlation between trap capture and mite density. In simulated ham aging rooms, the distribution of mites on hams was determined and different sampling techniques such as vacuum sampling, trapping, rack sampling, ham sampling and absolute mite counts from whole hams were compared and correlated. Results showed weak or moderate correlations between sampling techniques in pairwise comparisons. Two sampling plans were developed to determine the number of samples required to estimate mite density on ham with respect to fixed precision levels or to an action threshold for making pest management decisions. Findings reported here can help in the optimization of trapping and sampling of ham mite populations to help in the development of efficient, cost-effective tools for pest management decisions incorporated with alternatives to methyl bromide.

O aproveitamento de células vivas de leveduras – Saccharomyces cerevisiae – como probiótico, e, componentes extraídos da parede celular desta levedura, como aditivos, para desejadas funções, têm sido objeto de interesse cada vez maior, pelos resultados promissores até então obtidos e, concomitantemente, pelo excedente de biomassa de leveduras gerado pela indústria de etanol e cerveja no Brasil. Por estes motivos, foram conduzidos dois experimentos, um com o objetivo de investigar a possibilidade de utilizar o milho como um veículo alternativo para a levedura S. cerevisiae – como probiótico, e outro, com o propósito de estudar a capacidade de reduzir danos promovidos pelas aflatoxinas, das leveduras vivas, das termolisadas e mananoligossacarídeos. O primeiro experimento foi montando em um arranjo fatorial 2x2x5, constituído de duas concentrações de leveduras (1 e 2%), grãos de milho com dois teores de umidade (16 e 20%) e 5 períodos de armazenamento (0, 15, 30, 90 e 110 dias), distribuído ao acaso, com 4 repetições. O outro estudo, foi um bioensaio, conduzido durante 28 dias, com ratos Wistar, em um experimento com delineamento inteiramente casualizado, com 7 tratamentos e 5 repetições. A concentração de células aplicadas nos grãos de milho não influenciou a viabilidade das leveduras durante o armazenamento. A umidade do substrato interferiu no desenvolvimento da viabilidade, e que, em substratos com maiores teores de umidade foram observadas menores médias de viabilidade durante o armazenamento. A viabilidade das células de leveduras permaneceu constante por 30 dias e aos 90 dias em armazenamento foram observadas reduções no número de células viáveis. As leveduras apresentaram viabilidade de 70% aos 110 dias em armazenamento. A inoculação de leveduras vivas em grãos de milho, visando a sua utilização como probiótico, é uma técnica viável. Os tratamentos com levedura termolisada e mananoligossacarídeos não foram capazes de reduzir os danos promovidos pelas aflatoxinas em nível de hepatócitos. As leveduras vivas foram capazes de reduzir os danos promovidos pelas aflatoxinas em nível celular. / The utilization of live cells of yeasts - Saccharomyces cerevisiae - as probiotic, and, extracted components of the cellular wall of this yeast, as addictive, to desired functions, have been object of interest, due the promising results until then obtained and, simultaneously, for the excess of biomass of yeasts generated by the etanol and beer industry in Brazil. For these reasons, two experiments were led, one with the objective of investigate the possibility to use the corn as an alternative vehicle for the yeast S. cerevisiae - as probiotic, and other, with the purpose of studying the capacity to reduce damages promoted by the aflatoxins of the live yeasts, termoliseds and mananoligossacarides. The first experiment was mounted in a factorial arrangement 2x2x5, constituted of two concentrations of yeasts (1 and 2%), corn grains with two moisture contents (16 and 20%) and 5 storage periods (0, 15, 30, 90 and 110 days), random arrangement, with 4 replications. The other study, was a bioassay, led during 28 days, with rats Wistar, in completely randomzed desing, with 7 treatments and 5 repetitions. The concentration of applied cells in the corn grains did not influence the viability of the yeasts during the storage. The moisture of the substrate interfered in the development of the viability, and that in substrate with bigger moisture contents smaller viability averages were observed during the storage. The viability of the cells of yeasts remains constant for 30 days and to the 90 days in storage reductions were observed in the number of viable cells. The yeasts presented viability from 70% to the 110 days in storage. The inoculation of live yeasts in corn grains, aiming its use as probiotic, is a viable technique. The treatments with yeast termolised and mananoligossacarídes were not capable of reducing the damages promoted by the aflatoxins in hepatocites level. The live yeasts were capable to reduce the damages caused by the aflatoxins in cellular level.

INVID Jönköping AB is an IT-consultant company. They are a part of the INVID-group that employ about 140 people and are represented in ten different locations in Sweden. INVIDs business areas include development and customization of web applications. The company has been developing a web publishing tool, INVID Publisher.NET. Small- and medium sized companies are offered hosting of a complete web portal/platform with Content Management System/Customer Relationship Management (CMS/CRM) functionality. Customers can manage the content published on web pages. They can choose among a set of templates were there are modules for example text/html and news. To find the right template for the purpose can be a difficult task for the customer. The purpose of our report is to an answer two main questions: • How to develop modules for DotNetNuke? • What is the foundation for the architecture and structure of DotNetNuke? Our goal was to create modules with the programming language VB.NET and server technology ASP.NET. We would take advantage of the DotNetNuke web application framework for developing modules that offer the customer a way to easily and effectively build new web pages with INVID Publisher .NET. The starting point for the module we have developed is based on analysis of former existing module that INVID AB was not comfortable with. We analysed and discussed the problems that the old module constituted. During the development of the module we also received feedback on our work from our tutor on INVID and other members of the development team. Our work has lead to a template module were the customer can create new web pages based on templates and also create new templates. INVID and we also consider our module to be graphically well designed. In the future it’s possible to further develop our module to a great extent because we have followed the principles of DotNetNuke and have written program code that is object-oriented, reusable, and extensible and is based on good programming principles and prominent design patterns. / INVID Jönköping AB är ett IT-konsult bolag. De ingår i INVID-gruppen som totalt sysselsätter drygt 140 personer och finns representerade på tio orter i Sverige. De är verksamma inom ett flertal IT-områden, däribland utveckling och anpassning av webbapplikationer. Företaget har under en tid arbetat med att utveckla ett webbpubliceringsverktyg, INVID Publisher.NET. Små- och medelstora- företag erbjuds en komplett webbportalplattform med Content Management System/Customer Relationship Management (CMS/CRM) funktionalitet sammankopplat med webbhotelltjänster som företaget erbjuder. Kunder har möjlighet att själva påverka det innehåll som finns publicerat på webbsidor. De kan välja bland ett antal mallar där det finns moduler för bl.a. text/bild och nyheter. Att hitta rätt mall för ändamålet kan dock vara svårt för kunden. Vårt examensarbetes frågeställningar var följande: • Hur utvecklar man en modul för DotNetNuke? • Vad ligger till grund för DotNetNukes arkitektur och uppbyggnad? Vårt mål var att skapa en eller flera moduler med programmeringsspråket VB.NET och servertekniken ASP.NET. Vi avsedde också att lära oss webbapplikationsramverket DotNetNuke för att bygga modul(er) som erbjuder kunden att enkelt och effektivt bygga nya sidor i INVID Publisher .NET. Utgångspunkten för den modul som vi utvecklade bygger på analyser av tidigare existerande mallmodul som företaget (INVID AB) inte var nöjda med. Vi analyserade och diskuterade de problem som den gamla modulen medförde. Under utvecklingens gång fick vi feedback på vårt arbete från vår handledare på företaget och andra personer från utvecklingsavdelningen. Examensarbetet har resulterat i en fungerande mallmodul där kunden kan med lätthet skapa nya sidor utifrån mallar och även skapa nya mallar. Uppdragsgivaren och vi anser att modulen som utvecklats är mycket grafiskt väldesignad. I framtiden kan modulen vidareutvecklas framgångsfullt bl.a. tack vare att vi i vårt utvecklingsarbete har följt DotNetNuke-ramverket och dess principer strikt. Vi har även skrivit kod som bl.a. karakteriseras av att den är objektorienterad, återanvändbar, utbyggbar och bygger på goda programmeringsprinciper och framstående designmönster.

Since the late 90s, support and services at SAAB have produced and maintained a product called ELDIS. ELDIS is an application used by Swedish armed forces at air bases in Sweden and flight technicians at air bases. It displays electrical information, wire diagrams, and detailed information for cables, electrical equipment, and other electrical devices. The main problem for ELDIS is that when drawing wire diagrams in the application, it takes too long of a time when the stored procedures are retrieving information from the database. There are two significant areas in this project, analyzing and optimizing stored procedures and implementing a client-side solution. This project aims to guide SAAB to choose the right approach for solving the performance issue of the application and display some of the problems that can exist with slow stored procedures for companies in general. This project has optimized the most used stored procedure at SAAB and compared it to a client-side solution and the original application. The result of this project is that both the optimized stored procedure implementation and the client-side implementation is a faster option than the original implementation. It also highlights that when trying to optimize the stored procedures, indexing on the database should be considered for increasing the performance of a stored procedure.

This study was undertaken to determine the effect of oxygen absorber packets (OAP) (AGELESS Z.300 E) in improving the shelf-life of selected dried food products, including dried potato pearls, dried sliced apple, dried carrot, white rice, nonfat dry milk, all purpose flour, rolled oats, and wheat. Items were stored at four different temperatures (-20, 10, 21, and 29.5°C) over a period of 24 months with observations at 6-month intervals. Hunter colorimeter, thiobarbituric acid reactive substance (TBARS) germination rate, gluten weight, and volume were parameters used as quality indicators of various dried foods. Statistical analysis indicated a significant time and temperature effect for almost all the stored products. Storage at a high temperature (29.5°C) renders OAP ineffective in reducing browning during storage. Potato pearls, dried sliced apple, and dried carrot exhibit darkening by the first 6 months of storage at 29.5°C regardless of oxygen status of the container. White rice showed yellowing under the same conditions. Most of the dried food products that were stored at 10 and 21°C with or without oxygen absorber packets maintained their color as indicted by a relatively constant lightness reading (L*) over time. TBARS values rose in all stored food with increasing storage time, especially when the dried products were stored at higher temperature (29.5°C). Statistical analysis indicated a significant OAP effect in reducing TBARS concentration over time. Germination of wheat kernel was reduced to less than 80% after 24 months of storage at 29.5°C. However, when stored with oxygen absorber packets, germination was still 86%. Storage length and temperature are the primary factors that determine the quality of home-stored dried food items.

No description available.

<p>Hermetic storage systems have gained global popularity for their ability to minimize stored product losses by depleting oxygen. However, relying solely on insects to deplete oxygen in hermetic storage, when this process takes longer, can result in (further) damage to stored commodities. This study was conducted to investigate: (i) the potential of four different germinating seeds (soybean, rice, cowpea, and corn) in scavenging oxygen within hermetic storage systems; (ii) the impact of container volume and the number of germinating seeds on oxygen depletion; and (iii) the effects of germinating seeds on insect mortality and grain quality. Among the crops tested, cowpea, during their fourth, fifth, and sixth germination stages (T4, T5, and T6), depleted oxygen below 5% within 12 hours. The fourth stage of cowpea (T4) was identified as a potential oxygen scavenger due to its shorter germination time and ease of handling. Moreover, increasing the number of germinating seeds resulted in a faster initial rate of oxygen depletion in all-sized jars. Doubling both the volume of the jars and the number of germinating seeds had a similar rate of oxygen depletion. Additionally, an equation was derived to predict the required number of germinating seeds based on data from different numbers of seed and container volume combinations. Relative humidity levels increased to approximately 90% when empty jars were used but remained consistent at 40% when the jars were filled with grains. Furthermore, using 10, 20, and 30 germinating cowpea seeds with stored grains and insects, oxygen levels were reduced below 5% at different time intervals. Complete adult mortality of <em>C. maculatus</em> was achieved within 3-5 days of exposure, depending upon the number of germinating seeds. 20 and 30 seeds achieved complete mortality within 72 hours, while 10 seeds required 120 hours. As the number of germinating seeds increased, egg counts decreased, and moisture content significantly increased in the treatment involving 30 seeds. Furthermore, no adult emerged after 96 and 120 hours of exposure to normoxia for the 30 and 20 seed treatments, respectively. However, in the 10 seeds treatment, a small percentage of adults (0.29%) did emerge even after 120 hours of exposure.</p>

No description available.