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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Flavor and Quality Characteristics of Two Primocane-bearing Blackberry Cultivars as Impacted by Foliar and Shade Application

Xu, Tianyou 28 July 2023 (has links)
Blackberry (Rubus spp.) is a popular fruit due to its delightful taste and notable health benefits. With a growing demand for regional blackberry production, this study aims to provide Virginia blackberry growers with information on the effectiveness of pre-harvest foliar treatments and shade application on yield, white drupelet disorder, post-harvest attributes, and the aroma profile of two blackberry cultivars, Prime-Ark® Traveler and Prime-Ark® Freedom. The field study was repeated in the 2021 and 2022 growing seasons at the Hampton Roads Agricultural Research and Extension Center in Virginia Beach, VA, in a completely randomized design. Grower standard control (GSC), shade cloth with 30% light reduction (SHA), calcium (CAL), and salicylic acid (SAL) foliar applications were randomly assigned to each variety. Fruit yield and physicochemical attributes of the blackberry were collected and analyzed, and aroma-active compounds in blackberries were identified by use of headspace-solid-phase microextraction-gas chromatography-mass spectrometry-olfaction (HS-SPME-GC-MS-O). Shade cloth significantly reduced the white drupelet disorder (WDD) in Prime-Ark® Freedom but it also reduced the total soluble solid content (°Bx) and °Bx/% titratable acidity (a ratio indicates the sweet and sour balance for fruit) for both cultivars. No significant improvement was found in the TSS, TA, firmness and yield of blackberries treated with CAL and SAL. In total, 16 consistent aroma-active compounds were found across treatments for both varieties and growing seasons. Foliar and shade application did not alter the aroma profile of either blackberry cultivar. However, higher volatile contents were found in 2021 than in 2022, possibly due to climate variation. A clear distinction on aroma profiles of the above two cultivars were also observed: PrimeArk® Freedom was higher in compounds possessing "fruity" and "floral" notes, while PrimeArk® Traveler featured more "green" and "fresh" characteristics. Regional berry growers should be more conservative when adopting foliar and shade applications due to potential seasonal variations surpassing the significance of agronomic treatments. / Master of Science in Life Sciences / Blackberry (Rubus spp.) with its inky purple color, juicy bursts of sweet and tart flavor, and various health benefits has become more popular recently. With growing demands for locally produced blackberries with better flavor, this study will provide Virginia blackberry growers with information on the effectiveness of pre-harvest foliar treatments and shade applications on yield, white drupelet disorder, post-harvest attributes, and aroma profile of two blackberry cultivars, Prime-Ark® Traveler and Prime-Ark® Freedom. The field study was repeated for two growing seasons 2021 and 2022 at the Hampton Roads Agricultural Research and Extension Center in Virginia Beach, VA. All blackberry plants received standard fertigation, with plots receiving additional either calcium or salicylic acid foliar spray, or shade cloth (black mesh cloth) application to reduce 30% direct sunlight. Fruit yield and post-harvest attributes such as sugar content, firmness, phenolic content, and aroma of the Virginia-grown blackberries were studied. Shade cloth (light reduction) was effective in mitigating discoloration in Prime-Ark® Freedom, but it also reduced the sugar content and sweet and sour balance for both varieties. Calcium and salicylic acid were not effective in improving the yield and fruit quality of blackberries. Fruit harvested in 2021 had a more intense aroma and taste when compared to the 2022 season, likely due to the excessive heat and drier climate in year 2. The two cultivars have different aroma profiles, with PrimeArk® Freedom being more "fruity" and "floral" and PrimeArk® Traveler featuring more "green" and "fresh" notes. This study suggests that regional berry growers should be more conservative when adopting agronomic practices such as foliar spray and shade applications due to seasonal variations (temperature, rainfall) possibly surpassing the effectiveness of agronomic treatments.
2

Study of Viruses Associated with Blackberry Yellow Vein Disease in Mississippi

Ghimire, Pratibha 17 May 2014 (has links)
Blackberry yellow vein disease (BYVD) is the most important virus disease of blackberry in the Southeastern United States. In order to determine viruses in BYVD-affected plants in Mississippi we tested a total of eighty one symptomatic cultivated and wild blackberries collected from different locations for infections by nine different viruses. All tested viruses were present in diseased samples at various rates, with the exception of Rubus canadensis virus 1. Blackberry yellow vein associated virus is prevalent virus in Mississippi, infecting 70% of tested samples, followed by Tobacco ringspot virus. The second part of this research focused on molecular and phylogenetic studies concerning a putatively new virus species, provisionally referred to as Blackberry virus X and present in approximately 27% of the tested samples. Data generated in this study suggest that BVX is a novel species in the family Betaflexiviridae, with final taxonomic allocation (at the genus level) yet to be determined.
3

The usability of mobile Twitter apps : Determining the usability of mobile Twitter apps on Smart phones.

Lehutjo, Tshepo. 30 January 2014 (has links)
This study looks at the usability of mobile Twitter applications running on Android and Blackberry operating systems. Usability is important for mobile Twitter applications, as 55% of active Twitter users access the social network service through their mobile devices. This study gathers empirical data that determines which mobile Twitter application is superior in terms of usability. The mobile Twitter applications evaluated and compared in this study are the official Twitter applications for Android and Blackberry and the third-party Twitter application: TweetCaster for Android and Blackberry. Data is gathered using the System Usability Scale and notes regarding time spent on tasks and the accuracy of task completion are kept, in order to measure satisfaction, efficiency, and effectiveness respectively. The findings of this study show that there is need for further studies and highlights further areas for improvement on mobile Twitter applications.
4

PREPARATION AND CHARACTERIZATION OF BLACKBERRY EXTRACTS AND THEIR ANTICANCER AND ANTI-INFLAMMATORY PROPERTIES

Dai, Jin 01 January 2009 (has links)
Blackberries are rich in polyphenols including anthocyanins. Polyphenols are hypothesized to have biological activities that impact positively on human health. The purpose of these studies was to develop phenolic extracts from selected cultivars of blackberries currently grown in Kentucky as potential Botanical Drug Products for the treatment and prevention of cancer and inflammatory diseases. An ultrasound-assisted ethanol extraction method was employed to obtain anthocyanin-containing extracts (ACEs) from puree or powder (lyophilized puree) of blackberries. ACEs were analyzed for total anthocyanin and phenolics content, polymeric color, and total antioxidant capacity (TAC). The influence of water content in the extraction system was evaluated. A 90 day stability study of the extract and a 48 h stability study of the extract in biologically relevant buffers were completed. HPLC-MS results showed the anthocyanins in ACE were mainly cyanidin-based. As compared to powder-derived ACEs, puree-derived ACEs contained similar amounts of anthocyanins, but greater levels of phenolics and increased TAC. The in vitro antiproliferative effects of ACEs were evaluated in human leukemia (HL- 60), colon (HT-29), and breast (MCF-7) cancer cells. The anticancer mechanism involving reactive oxygen species (ROS) generation was investigated. It was found puree-derived ACEs significantly enhanced production of H2O2 and cytotoxicity in all cell lines as compared to powder-derived ACEs. Cyanidin 3-glucoside exerted anticancer effect by acting synergistically or additively with other active components in the extracts. Furthermore, the phenolic-enriched fractions were separated from non-phenolic fractions in ACEs and found to have potent antioxidant and antiproliferative activities. Pureederived ACE and corresponding phenolic-enriched methanol fraction (MF) induced cell death through ROS-independent caspase 3 pathway whereas the cytotoxicity induced by powder-derived ACE and corresponding MF is related to ROS mechanisms. The in vitro anti-inflammatory studies showed ACEs inhibited Lipid A-induced Interleukin-12 (IL-12) release from mouse dendritic cells, and modulated lipopolysaccharide (LPS)-induced secretion of tumor necrosis factor-α (TNF-α) and Interleukin-6 (IL-6) from murine macrophages. These studies have important implications for the potential use of blackberry extracts for the treatment and prevention of cancer and inflammation diseases and provide essential information for the development of Botanical Drug Products from extracts derived from blackberries and other fruits.
5

"Finns det i Sverige?" : En studie om varför BlackBerry inte fått större genomslag på den svenska smartphonemarknaden

Larsson, Sofia, Sjögren, Jenny January 2011 (has links)
No description available.
6

Lietuvoje augančių gervuogių vaisių fitocheminės sudėties įvairovės tyrimas / Phytochemical composition diversity assay of blackberry fruits growing in Lithuania

Šlajūtė, Jolanta 30 June 2014 (has links)
Šio tyrimo tikslas yra įvertinti gervuogių (Rubus caesius L. ir Rubus nessensis Hall.) vaisių antocianinų sudėtį ir jos įvairavimą skirtingu nokimo metu bei vaisių ekstraktų antiradikalinį aktyvumą. Vienas iš tyrimo objektų yra dviejų skirtingų Rubus genties atstovų (Rubus caesius L. ir Rubus nessensis Hall.) vaisiai, kurie buvo renkami periodiškai kas savaitę nuo pat vaisių derėjimo pradžios, Šilutės rajone. Nustačius optimalias ekstrahavimo sąlygas, vaisių etanoliniai ekstraktai buvo tiriami spektrofometrijos metodu bei nustatomas ekstraktų antiradikalinis aktyvumas, atliekant fotometrinius 2,2-difenil-1-pikrilhidrazilo (DPPH) bei 2,2’-azino-bis-(3-etilbenztiazolin-6-sulfono rūgšties) (ABTS) radikalo katijono sujungimo metodus, o gauti rezultatai vertinami remiantis pagal tai, kurią nokimo savaitę buvo renkami vaisių mėginiai. Antrasis tyrimo objektas – R.caesius L. vaisiai, surinkti iš įvairių Lietuvos vietovių, kurių etanolinių ekstraktų sudėtyje esantis antocianinų suminis kiekis taip pat buvo vertinamas spektrofotometrijos metodu, tačiau šioje tyrimo dalyje buvo siekiama nustatyti antocianinų sudėties įvairavimą priklausomai nuo gervuogių vaisių rinkimo vietovės. Tyrimo rezultatai. Nustatyta, jog iš dviejų tirtų gervuogių rūšių, gausesne antocianinų frakcijos sudėtimi pasižymi R. caesius L. vaisių ekstraktai, kuriuose antocianinų kiekis siekė nuo 4,16 proc. iki 4,89 proc. sausoje žaliavos masėje. Atitinkamai R. nessensis Hall. vaisių ekstraktuose nustatyta antocianinų... [toliau žr. visą tekstą] / The objective of this study is to evaluate the blackberry (Rubus caesius L and Rubus nessensis Hall.) fruit’s anthocyanin composition and its variation during different ripening time and also to measure the antiradical activity in fruit extracts. One of the objects of the study is two different Rubus genus (Rubus caesius L. and Rubus nessensis Hall.) fruits, which were collected weekly from the beginning of fruit bearing in Šilutė’s area. Once the optimum extraction conditions were determined, the ethanol extracts of the fruits have been investigated using spectrophotometry and their antiradical activity was investigated using photometric 2,2- diphenyl-1-picrylhydrazyl (DPPH) and 2,2 '-azine-bis-(3- ethylbenzthiazoline-6-sulfonic acid ) (ABTS) radical scavenging techniques, and the results were evaluated according to the time, when fruit samples were collected. The second object of the research - R.caesius L. fruits collected from different locations in Lithuania. The total amount of anthocyanins in the extracts was also determined using spectrophotometry, but in this part of the study the main point was to determine how the variation of anthocyanins depends on the blackberry fruit collection area. The results showed that from two studied species of blackberry, R. caesius L. fruit extracts contained a larger amount of anthocyanin’s fraction, compared to R. nessensis Hall. fruits. In R. caesius L. fruit extracts anthocyanin’s concentration ranged from 4,16 percent to 4.89... [to full text]
7

Compostos bioativos em amora-preta e encapsulação do seu extrato antocianico por gelificação termica com curdlana / Bioactive compounds in blackberry (Rubus spp.) and encapsulation of blackberry anthocyanins using gelification of curdlan

Ferreira, Daniela Souza, 1978- 15 July 2008 (has links)
Orientador: Adriana Zerlotti Mercadante / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia de Alimentos / Made available in DSpace on 2018-08-11T06:49:41Z (GMT). No. of bitstreams: 1 Ferreira_DanielaSouza_M.pdf: 861449 bytes, checksum: 0972445ef423fb371289eeef23009060 (MD5) Previous issue date: 2008 / Resumo: Dentre as várias opções de espécies frutíferas com boas perspectivas de comercialização, surge a amora-preta (Rubus spp.) como umas das mais promissoras. A amora-preta é uma pequena fruta que tem apresentado sensível crescimento nos últimos anos no Rio Grande do Sul, Sul de Minas Gerais e tem elevado potencial para ser cultivada no estado de São Paulo. No Rio Grande do Sul, a amora-preta tem tido grande aceitação pelos produtores, devido ao seu baixo custo de produção, facilidade de manejo, rusticidade e pouca utilização de defensivos agrícolas. Muitos fitoquímicos presentes em amora-preta exibem propriedades benéficas à saúde, como compostos fenólicos, com destaque para os pigmentos antociânicos. Estes pigmentos, que conferem a coloração atraente à fruta, possuem baixa estabilidade frente a algumas condições do meio como pH neutro e alcalino, alta temperatura e presença de luz. Assim, através deste estudo foram determinados espectrofotometricamente o teor de alguns compostos bioativos presentes em amora-preta cultivar Tupy, como antocianinas totais, monoméricas, poliméricas e copigmentadas, além de compostos fenólicos totais, flavonóides totais e carotenóides. A atividade antioxidante foi avaliada frente aos radicais ABTS e DPPH. Por cromatografia líquida de alta eficiência (HPLC), acoplada em série a detectores de arranjo de diodos (PDA) e de espectrômetro de massas (MS) foram identificadas as antocianinas e os carotenóides presentes no extrato de amora. Com o intuito de aumentar a estabilidade das antocianinas, o extrato antociânico da amora-preta foi encapsulado utilizando a técnica de gelificação térmica. O material de parede selecionado foi a curdlana por não perder a capacidade gelificante em pH abaixo de 2. Após o processo de encapsulação foram avaliadas algumas características das partículas como o tamanho médio, a eficiência de encapsulação e o perfil de liberação do recheio. As antocianinas identificadas em amora-preta foram cianidina 3-glucosídeo, cianidina 3-dioxalil-glucosídeo, cianidina 3-malonil-glucosídeo e cianidina 3- rutinosídeo. A antocianina majoritária foi a cianidina 3-glucosídeo perfazendo 92,9 % da área total. O teor de antocianinas totais foi de 90,5 ± 0,1 mg/100 g, sendo composto por 76,2 ± 0,3 % de monoméricas, 22,8 ± 0,4 % de poliméricas e 1,6 ± 0,1 % de copigmentadas. As antocianinas monoméricas foram encontradas como 104,1 ± 1,7 mg em cianidina 3-glucosídeo/100 g de fruta. Foi observado que a amora-preta possui baixo teor de carotenóides (86,5 ± 0,1 mg/100 g) e os carotenóides encontrados foram: all-trans-b-caroteno (39,6 %), all-trans-luteína (28,2 %), all-trans-b-criptoxantina (13,9 %), 9-cis-b-caroteno (3,8%), all-trans-a-caroteno (3,3 %), 13-cis-b-criptoxantina (3,1 %), all-transzeaxantina (2,7 %), 13-cis-b-caroteno (1,7 %), 5,6-epóxi-b-criptoxantina + fitoeno (0,8%), além de um carotenóide não identificado representando 2,9 %. Com a presença de elevados teores de compostos fenólicos totais (241,7 ± 0,8 mg/100 g) e de flavonóides totais (173,7 ± 0,7 mg/100 g), pode-se concluir que estes compostos presentes na amora-preta foram os principais responsáveis pela elevada capacidade antioxidante avaliada pela habilidade de capturar radicais livres ABTS (TEAC 2209,7 ± 68,4 mM/ g) e DPPH (EC50 33,8 ± 1,8 g amostra/g DPPH). As partículas formadas por gelificação térmica com 4,3, 5,1 e 5,6 % de curdlana apresentaram forma esférica e multinucleada. A distribuição de tamanho apresentou perfil semelhante para as diferentes concentrações de curdlana, embora as partículas obtidas com maior concentração de curdlana (5.6 %) apresentaram maior uniformidade no tamanho, maior umidade e maior eficiência de encapsulação. O perfil de liberação de todas as partículas contendo antocianinas apresentou cinética exponencial de primeira ordem, com total liberação nos primeiros 20 minutos em tampão pH 1,0 / Abstract: Among the fruit species with good perspectives for commercialization, blackberry fruit (Rubus spp.) is one of the best options. Blackberry is a small fruit, which has been increasingly cultivated in Rio Grande do Sul State, South of Minas Gerais State, also presenting high potential for cultivation in São Paulo State. In Rio Grande do Sul, blackberry has been widely accepted by the farmers, due to its low production cost, easy handling, rusticity and use of low amounts of agricultural defensives. Several phytochemicals found in blackberry, such as phenolic compounds and anthocyanins, show beneficial health properties to humans. The anthocyanins, responsible for the attractive color of blackberries, possess low stability in some medium conditions, such as neutral and alkaline pH, high temperature and presence of light. Thus, using spectrophotometric methods, the levels of some bioactive compounds were determined in blackberries cv. Tupy, such as total anthocyanins, monomeric, polymeric and copigmented anthocyanins, as well as phenolic compounds, total flavonoids and total carotenoids. The antioxidant activity was determined using the free radicals ABTS and DPPH. Both anthocyanins and carotenoids from blackberry extracts were separated and identified by high performance liquid chromatography (HPLC) connected in series to diode array (PDA) and mass spectrometer (MS) detectors In order to increase the anthocyanin stability, the anthocyanic blackberry extract was encapsulated by thermal gelification. Curdlan was the wall material selected, since the gel formed was stable in pH values lower than 2. After the encapsulation process, some particle characteristics, such as medium size, encapsulation efficiency and release profile, were evaluated. The anthocyanins identified in blackberry were cyanidin 3-glucoside, cyanidin 3-dioxalyl-glucoside, cyanidin 3-malonil-glucoside and cyanidin 3-rutinoside. The major anthocyanin was cyanidin 3-glucoside, representing 92.9 % of the total area. The levels of total anthocyanins were 90.5 ± 0.1 mg/100 g, composed by 76.2 ± 0.3 % of monomeric, 22.8 ± 0.4 % of polymeric and 1.6 ± 0.1 % of copigmented ones. The monomeric anthocyanins were quantified as 104.1 ± 1.7 mg of cyanidin 3-glucoside/100 g of fruit. The levels of carotenoids found in blackberry were low (86.5 ± 0.1 mg/100 g), represented by all-trans-b-carotene (39.6 %), all-trans-lutein (28.2 %), all-trans-b-cryptoxanthin (13.9 %), 9-cis-b-carotene (3.8%), all-trans-a-carotene (3.3 %), 13-cis-b-cryptoxanthin (3.1 %), all-trans-zeaxanthin (2.7 %), 13-cis-b-carotene (1.7 %), 5,6-epoxy-b-cryptoxanthin + phytoene (0.8%), and a not identified carotenoid representing 2.9 %. The elevated levels of phenolic compounds (241.7 ± 0.8 mg/100 g) and flavonoids (173.7 ± 0.7 mg/100 g) are most probably responsible for the high antioxidant activity against the free radicals ABTS (TEAC 2209.7 ± 68.4 mM/100g) and DPPH (EC50 33.8 ± 1.8 g sample/g DPPH). The particles formed by thermal gelification with 4.3, 5.1 and 5.6 % of curdlan presented spherical and multinucleated forms. The profiles of the size distribution were similar for all curdlan concentrations; although the particles with the highest curdlan concentration (5.6 %) showed highest size distribution uniformity, highest moisture and highest encapsulation efficiency. The release profile of anthocyanins from all particles followed first-order kinetics, with total release in 20 minutes in buffer pH 1.0 under agitation at room temperature / Mestrado / Mestre em Ciência de Alimentos
8

Systém pre podporu sploupráce v danej firme / Collaboration tools within a given company

Dedíková, Zuzana January 2012 (has links)
The diploma thesis deals with the specific collaborative tools used in given company. It aims to validate the hypotheses selected within the surveyed company. The thesis is divided into two parts. The first part contains theoretical bases of the thesis. It outlines issues of information technology and communication tools since their beginnings towards the latest trends. The focus is on enterprise Microsoft and its products Microsoft Lync, Microsoft SharePoint and Windows Phone and enterprise BlackBerry and its contribution to the development and use of mobile communication devices. The practical part contains characteristics of surveyed company, the process of creating the survey, methodology, analysis and evaluation of given hypotheses.
9

Development and Evaluation of a BlackBerry-based Wearable Mobility Monitoring System

Wu, Hui Hsien 05 January 2012 (has links)
A Wearable Mobility Monitoring System (WMMS) can be an advantageous device for rehabilitation decision-making. This thesis presents the design and evaluation of a proof-of-concept WMMS that uses the BlackBerry Smartphone platform. A Java program was developed for the BlackBerry 9550, using the integrated tri-axial accelerometer, Global Positioning System sensor (GPS), CMOS digital video camera, and timer to identify change-of-state (CoS) among static states, dynamic states, small activity of daily living (ADL) movements, and car riding. Static states included sitting, lying, standing, and taking an elevator. Dynamic states included walking on level ground, walking on stairs, and walking on a ramp. Small activity of daily living movements included bathroom activities, working in the kitchen, and meal preparation. Following feature extraction from the sensor data, two decision trees were used to distinguish CoS and mobility activities. CoS identification subsequently triggered video recording for improved mobility context analysis during post-processing.
10

Acquiring Multimodal Disaggregate Travel Behavior Data Using Smart Phones

Taghipour Dizaji, Roshanak 23 January 2013 (has links)
Despite the significant advances that have been made in traffic sensor technologies, there are only a few systems that provide measurements at the trip level and fewer yet that can do so for all travel modes. On the other hand, traditional methods of collecting individual travel behavior (i.e. manual or web-based travel diaries) are resource intensive and prone to a wide range of errors. Moreover, although dedicated GPS loggers provide the ability to collect detailed travel behavior data with less effort, their use still faces several challenges including the need to distribute and retrieve the logger; the potential need to have the survey participants upload data from the logger to a server; and the need for survey participants to carry another device with them on all their trips. The widespread adoption of smart phones provides an opportunity to acquire travel behavior data from individuals without the need for participants to record trips in a travel diary or to carry dedicated recording devices with them on their travels. The collected travel data can then be used by municipalities and regions for forecasting the travel demand or for analyzing the travel behavior of individuals. In the current research, a smart phone based travel behavior surveying system is designed, developed, and pilot tested. The custom software written for this study is capable of recording the travel characteristics of individuals over the course of any period of time (e.g. days or weeks) and across all travel modes. In this system, a custom application on the smart phone records the GPS data (using the onboard GPS unit) at a prescribed frequency and then automatically transmits the data to a dedicated server. In the server, the data are stored in a dedicated database to be then processed using trip characteristics inference algorithms. The main challenge with the implemented system is the need to reduce the amount of energy consumed by the device to calculate and transmit the GPS fixes. In order to reduce the power consumption from the travel behavior data acquisition software, several techniques are proposed in the current study. Finally, in order to evaluate the performance of the developed system, first the accuracy of the position information obtained from the data acquisition software is analyzed, and then the impact of the proposed methods for reducing the battery consumption is examined. As a conclusion, the results of implemented system shows that collecting individual travel behavior data through the use of GPS enabled smart phones is technically feasible and would address most of the limitations associated with other survey techniques. According to the results, the accuracy of the GPS positions and speed collected through the implemented system is comparable to GPS loggers. Moreover, proposed battery reduction techniques are able to reduce the battery consumption rate from 13.3% per hour to 5.75% per hour (i.e. 57% reduction) when the trip maker is non-stationary and from 5.75% per hour to 1.41% per hour (i.e. 75.5% reduction) when the trip maker is stationary.

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