Sources of E. coli were determined from impaired waterways in the Appomattox River watershed (in the lower Piedmont and South-Central Virginia) for the development of bacterial Total Maximum Daily Loads (TMDLs). The Appomattox River watershed is primarily undeveloped with 70.8% of the land forested, 17.0% used for agriculture (mainly livestock production), and 7.7% classified as water, wetland or barren land. The remaining 4.5% is developed for residential, commercial, and industrial land uses (mainly within the city of Petersburg). Using Antibiotic Resistance Analysis, a known source library of 1,280 E. coli isolates (320 isolates per source) was constructed. Water samples were collected monthly for between eleven and fourteen months (11/02-12/03) from 40 locations throughout the Appomattox watershed and analyzed for fecal coliforms, E. coli, and resistance to 7 antibiotics of varying concentrations. A total of 486 water samples (9,907 isolates) were analyzed during the study. The objectives of this study were verify that each sampling site exceeded state bacterial count standards (using fecal coliform data), to compare the Discriminate Analysis and Logistic Regression statistical models for use in the classification of isolates, and finally to determine the source of contamination at each site. The fecal coliform and E.coli data was used to determine if each site exceeded state standards during the assessment period. Thirty-eight of the sites exceeded the fecal coliform standard at least 10% of the time, and thirty-three exceeded the E.coli standard at least 10% of the time. Discriminate Analysis (DA) is typically used to classify isolates, but the results obtained from the DA model were unrealistic based on the watershed land uses. By statistically analyzing the original 1,280 E.coli isolates six different ways, a more appropriate classification of isolates was determined. The six analyzing methods were Regular DA and Logistic Regression (LR); DA and LR where each isolate whose probability fell below 80% was deleted; DA and LR where each isolate whose probability fell below 80% was used to create an Unknown category. The Logistic Regression model with an Unknown category proved to be the most appropriate. By using the Logistic Regression model, with Unknown category, to classify isolates, twenty five of the forty sites were discovered to be contaminated predominately with Livestock and fourteen of the sites predominately by Wildlife. One site was equally divided between these two categories. Human and Pet contamination were not dominant at any of the forty sites. This comparison of the DA and LR statistical methods could change the analysis standard for Bacterial Source Tracking and suggests that the model required to classify isolates depends on the watershed characteristics. / Master of Science

Made available in DSpace on 2016-08-17T17:11:04Z (GMT). No. of bitstreams: 1 DISSERTACAO_ARIEL DE ALMEIDA COELHO.pdf: 1092576 bytes, checksum: 5f74aa9cceb65b68fc6d8633937e2c89 (MD5) Previous issue date: 2014-03-20 / FUNDAÇÃO DE AMPARO À PESQUISA E AO DESENVOLVIMENTO CIENTIFICO E TECNOLÓGICO DO MARANHÃO / This study aimed to verify the effect of bovine somatotrophin (bST) on sexual development, semen and endocrine traits in peripubertal buffalo. A total of 20 male Murrah buffaloes (Bubalus bubalis) (14 months of age) were randomly distributed into two treatments (bST vs control). The body weight, body condition score, testicular measurements, semen traits and IGF-I levels were evaluated once a month for a year. The ejaculate was collected by electroejaculation and physical and morphological analyzes were proceeded. Data analysis was performed using the Statistical Analysis System for Windows, SAS®. There was no difference (P>0.05) between bST and Control treatments on body weight or body condition score. Testicular measurements also showed no differences (P>0.05) between treatments, but increases significantly in a similar trend. There was no positive effect of bST treatment on age at first appearance of spermatozoa in the ejaculate (P> 0.05), but the bST group showed a significant tendency to increase the number of animals exhibiting puberty at each breeding soundness evaluation (P = 0.054). Sperm motility, vigor and percentage of abnormalities showed no difference (P>0.05). There was no difference (P>0.05) between bST and Control treatments on IGF-I serum concentrations. In conclusion, the use of bST did not result in positive effects on sexual development, semen traits and endocrine profile of male buffaloes in peripubertal period. / Objetivou-se com este estudo verificar o efeito da somatotropina bovina (bST) sobre o desenvolvimento sexual, características seminais e hormonais em bubalinos no período peripuberal. Um total de 20 búfalos machos, não castrados, da raça Murrah (Bubalus bubalis) (12 meses de idade) foram distribuídos em dois tratamentos (bST vs controle) em um delineamento de blocos ao acaso com dez repetições. O peso corporal, escore de condição corporal, biometria testicular, características seminais e os níveis de IGF-I foram avaliados uma vez por mês durante oito meses. O ejaculado foi coletado por eletroejaculação e submetido a análise física e morfológica. A análise dos dados foi realizada utilizando o Statistical Analysis System for Windows, SAS®. Não houve diferença (P> 0,05) entre os tratamentos bST e Controle no peso e no escore de condição corporal. As mensurações testiculares também não apresentaram diferenças (P> 0,05) entre os tratamentos, mas aumentaram com a idade significativamente em uma tendência similar. Não houve efeito positivo do tratamento com bST sobre a idade ao aparecimento dos primeiros espermatozóides no ejaculado (P>0,05). O bST apresentou uma tendência significativa em antecipar a puberdade (P = 0,054). A motilidade, vigor e percentual de anormalidades espermáticas não apresentou diferença (P> 0,05) entre tratamentos. Não houve diferença (P> 0,05) entre os tratamentos bST e Controle nas concentrações séricas de IGF-I. Em conclusão, o uso de bST não resulta em efeitos positivos sobre o desenvolvimento ponderal e sexual em bubalinos machos no período peripuberal.

Behavioral Skills Training (BST) is an evidence-based practice used to teach a wide variety of skills to different populations (Erhard et al., 2019; Parson et al., 2012; Reed et al., 2018; Tomlinso et al., 2018). BST can be used to perform Discrete-trial teaching (DTT), which is an effective teaching procedure that simplifies teaching for children with developmental disabilities and helps to expand their repertoires (Sarokoff & Sturmey, 2004). In the past, virtual-BST, which is a cost-effective and convenient method (LeBlanc et al., 2020; Tomlinson et al., 2018), has been used to teach individuals how to implement Applied Behavior Analysis interventions (Rios et al., 2020). The purpose of the current study was to compare the effectiveness of in-person BST and virtual BST to train three caregivers and three behavior technicians to implement DTT with children diagnosed with autism spectrum disorder. Using a multiple baseline across participants design, results of the current study indicated that, after the introduction of BST, participants in both groups (i.e., in-person BST and virtual BST) showed a high improvement in DTT implementation skills compared to baseline. Findings suggest that both modalities of BST are effective methods for training individuals on how to implement DTT.

The dependence of dielectric permittivity on the applied electric field, high dielectric constant and low cost makes barium strontium titanate (BST) a promising ferroelectric material for applications in tunable microwave devices. High tunability and low dielectric loss is desired for tunable microwave devices. The primary objective of this research was to optimize the tunability and dielectric loss of BST thin films at microwave frequencies with different deposition techniques. Ba0.5Sr0.5TiO3 thin films were grown on Pt/TiO2/SiO2/Si, by pulsed laser deposition (PLD) and sputtering. Parallel plate capacitor structures were designed using ADS and fabricated. The microstructural and phase analysis of the BST films were performed using X-ray diffraction (XRD) method. The diffraction patterns are attributed to cubic (perovskite) crystal system. The analysis of surface morphology was done using atomic force microscopy. Electrical properties of parallel plate capacitors were measured using LCR meter and tunability of 2.4:1 and loss tangent of 0.05 was achieved at low frequencies for laser deposited BST thin films. Tunability of 2.8:1 and loss tangent of 0.03 was achieved at low frequencies for sputtered BST thin films. The correlation of optimized structural and dielectric properties of thin films deposited by pulsed laser deposition and sputtering technique was analyzed and compared. The structural characterization of sputtered BST thin film on MgO, Alumina and LaAl2O3 was achieved for the fabrication of interdigital capacitors. Interdigital capacitor has been designed using ADS momentum.

The objective of this research is to implement monolithic analog phase shifters based on barium strontium titanate (BST) coated sapphire substrates for IEEE 802.11b wireless local area network (WLAN) applications. It has been known that several BST thin film properties such as high relative permittivity, electric field dependence, fast polarization response, relatively low loss, and high breakdown field, allow for miniaturization and high performance of analog phase shifters. Before attempting to implement BST phase shifters, coplanar waveguides (CPWs) and interdigital capacitors (IDCs) based on various BST compositions and thicknesses have been developed and characterized to capitalize on the electrical properties of BST thin films. Based on the characteristics of BST thin films, two design topologies have been studied to implement phase shifters. The first topology is a reflection-type structure. The reflection-type phase shifter composed of a 3-dB coupler and two identical reflective terminations has provided a large phase shift with a relatively low insertion loss. The second topology is an all-pass network structure. The all-pass network phase shifter consists of only lumped elements so that one can shrink in size of devices. The total chip area of the all-pass network phase shifter is only 2.6 mm * 2.2 mm with a loss figure-of-merit (FOM) of more than 69 deg/dB at 2.4 GHz. This is the smallest size and the best performance obtained to date for BST phase shifters in the 2.4 GHz band and comparable or even better than the state of the GaAs MMIC phase shifters. The nonlinear response of the all-pass network phase shifter also was investigated with two-tone intermodulation distortion (IMD) measurement. Furthermore, the all-pass network phase shifter was studied to ascertain a design to ensure minimum performance variation over a range of temperature and to determine which BST composition performed best in the face of temperature variations. Compact beamforming networks (BFNs) for WLAN systems using client-based smart antennas have been demonstrated to validate the feasibility of BST technology for WLAN applications. The two-element BFNs have been shown to increase throughput and network capacity by rejecting interference.

Maintenance of staff training continues to be problematic at agencies that serve individuals with developmental disabilities, due to high client to staff ratios, staff turnover and lack of time and resources for training. The purpose of this study was to find a refresher method that staff could independently access that would be effective, as well as convenient and non-aversive. Seven staff participants at a day program for adults with developmental disabilities were trained on two client intervention plans using a Behavioral Skills Training (BST) method. Each group was given follow-up training: one group received a video refresher; one utilized flashcards and one served as the control group. All participants increased correct responses after BST training. While all participants also maintained a higher percentage of correct responses after maintenance training, all of the video and one of the flashcard group participants exhibited higher scores in the last few months of the study than did the control group. Participant surveys revealed that the videos were the most preferred method of maintenance training; participants thought they would be most likely to independently access videos over flashcards, if the resources were made available.

Abstract The recent trend in low temperature co-fired ceramic (LTCC) technology is to integrate more elements into multilayer modules. This thesis describes work specifically aimed at developing ferroelectric barium strontium titanate (BST) for integration into such modules. In particular, an objective was the development of a novel, electric field controlled, tunable component to be used at microwave frequencies (2–26 GHz). For the application envisaged, relative permittivity is required to be low (100–1000) and adjustable by a suitable applied electric field, the dissipation factor at room temperature must be low (~0.001) at 2–26 GHz, and most importantly, the sintering temperature must be suited to the LTCC technology (~900 °C) Initial work was focused on sol-gel derived Ba0.7Sr0.3TiO3 powders with boron oxide addition, which were sintered at 900 °C, the dissipation factor was 0.006. The dissipation factor was not low enough for the desired microwave application, and attention turned to powders prepared by the mixed-oxide route. The Ba0.7Sr0.3TiO3 powders, fluxed with the optimum amounts of boron oxide and lithium carbonate, could be sintered at 890 °C to the same density as is achieved with un-fluxed Ba0.7Sr0.3TiO3 sintered at 1360 °C. The dissipation factor for this fluxed powder was acceptably low, although permittivity was too high for the particular objective. Subsequently, research was on BST modified by magnesia, 0.4Ba0.55Sr0.45TiO3-0.6MgO (BSTM). With the optimum fluxing additives, the sintering temperature necessary to achieve a dense BSTM-based ceramic was reduced to 950 °C. The developed microstructure was good, and the relative permittivity and dissipation factor values (221, 0.0012 at 1 kHz) at room temperature indicated good microwave properties. Studies were also undertaken with organic-based tape-casting slurries, laminating procedures and burn-out and sintering schedules. Several kinds of tapes were fabricated and characterized. A test structure for the measurement of dielectric properties at 26 GHz of the optimized BSTM-based ceramic was constructed. The specimen was 50 μm thick layer of BST on an alumina substrate. The relative permittivity and tunability were 130 and >15 % at 4 V μm-1 at room temperature. A tunable phase-shifter was fabricated from the same BSTM-based tape using a novel gravure printing technique, and measurements at 26 GHz showed phase shift from 10 to 35° when the electric field was increased from 1 V μm-1 to 2.5 V μm-1. Some exploratory experiments are described to assess the compatibility of the developed BST-based LTCC with commercial LTCC and some electroceramics.

Made available in DSpace on 2014-06-12T23:04:09Z (GMT). No. of bitstreams: 2 arquivo8906_1.pdf: 544189 bytes, checksum: d9554187d2d520387234985b0ae8c669 (MD5) license.txt: 1748 bytes, checksum: 8a4605be74aa9ea9d79846c1fba20a33 (MD5) Previous issue date: 2003 / A somatotropina bovina recombinante (BST) tem sido utilizada como ferramenta para incrementar a produção leiteira em ruminantes, podendo ser aplicada à caprinocultura leiteira do Nordeste. A presente pesquisa foi realizada com o objetivo de verificar o efeito da BST sobre a produção e a qualidade do leite de cabra, de raças exóticas submetidas a diferentes níveis de concentrado, no semi-árido nordestino. O experimento foi conduzido na Embrapa/Caprinos, em Sobral-Ceará. Utilizou - se cabras leiteiras das raças Anglo-Nubiana (16) e Saanen (14), adultas, selecionadas de acordo com o nível de produção e a ordem de parição. Para avaliação da produção leiteira foram aplicadas quatro doses de BST (3,0 mg/ kg / PV), em intervalos de 14 dias. A avaliação da composição físico-química foi realizada através da determinação dos teores de proteína, gordura, lactose, minerais, acidez, densidade, extrato seco total e extrato seco desengordurado. Testes de aceitabilidade e diagnóstico de atributos foram realizados para avaliação sensorial do leite de cabra das raças em estudo. Após avaliações estatísticas, observou-se que a administração de BST aumentou (p<0,05) a produção de leite (36%) e a produção de leite corrigida (43%) de cabras, de raças exóticas na região semi-árida do Nordeste. A administração de BST não alterou a composição físicoquímica do leite de cabra das raças Anglo-Nubiana e Saanen. Essas características foram afetadas pela raça (p < 0,05). O leite de cabra dos animais não tratados comBST teve maior aceitação do que o leite de animais suplementados com o produto. O sabor do leite da raça Saanen teve melhor aceitação do que o da raça Anglo Nubiana, porém, ambos foram classificados como gostei moderadamente . O leite de cabra foi caracterizado como sendo um leite de cor branca clara, sabor doce leve e apresentando fraco odor estranho

Bone marrow stromal antigen 2 (BST-2/tetherin) is a type II transmembrane protein that plays various roles, including protective and detrimental roles in the host. Cellular responses to BST-2 expression or the lack thereof, may be cell type and context-dependent and may vary with time. When protective, BST-2 functions as an antiviral factor, renowned for its ability to tether budding enveloped viruses to the membrane of infected cells. Tethering of budding virions prevents their release into the extracellular milieu limiting infection of naïve cells. The antiviral role of BST-2 has been predominantly studied using cultured cells. Insight into the role of BST-2 in inhibition of viral infection in vivo came from our study of the alphavirus Chikungunya virus (CHIKV) and the retrovirus mouse mammary tumor virus, (MMTV). BST-2 prevents the release of CHIKV and MMTV virions from infected cells and limits the replication of both viruses in mice. In the context of CHIKV infection, BST-2 protects the host in a tissue-type dependent manner. In lymphoid and most non-lymphoid tissues, expression of BST-2 limits CHIKV replication. In addition, BST-2 regulates CHIKV-induced inflammatory responses in mice, an indication that BST-2 may function to initiate and amplify innate immune responses. Host response to MMTV infection depends on the stage of the infection and disease sequela. Acute infection of immune cells with MMTV results in an initial increase in BST-2 expression followed by a sharp decline. In contrast, in MMTV-induced mammary tumors, BST-2 mRNA and protein are elevated, so is the viral load. This is an indication that the antiviral role of BST-2 is not operative once mammary tumors have developed. These data provided the initial evidence that BST-2 may promote breast cancer progression. Indeed, data from two mouse models of breast cancer show that expression of BST-2 is necessary for cell to cell and cell to extracellular matrix interactions. Thus, BST-2 expression in breast cancer cells enhances cancer cell adhesion, anchorage-independency, migration, and invasion, culminating in increased tumor mass, increased metastases, and reduced host survival. Structurally, BST-2 homodimerization is important for its cancer-promoting role as dimers of BST-2 regulate anchorage-independency, resistance to anoikis, and enhanced adhesion between cancer cells and components (proteins and cells) of the tumor microenvironment. How BST-2 is enriched in breast cancer cells was elusive until our in silico analyses of a large human breast cancer dataset that revealed the involvement of epigenetic regulation of BST-2 in breast tumors. In highly aggressive breast cancers, specific CpG sites in and at close proximity to the BST-2 promoter are hypomethylated. This is in sharp contrast to non-aggressive luminal cancers and normal breast epithelial cells. These data suggest that a progressive loss of methylation on the BST-2 gene may contribute to constitutive overexpression of BST-2 in tumors. Overall, these findings show that 1) BST-2 contributes to the emergence and progression of breast malignancies and may be used as a therapeutic target or as a biomarker for aggressive breast cancers; and, 2) BST-2 acts as a viral sensor to initiate antiviral inflammatory responses and could be exploited therapeutically to treat viral infections. We highlight the need for additional research on the antiviral and cancer-promoting roles of BST-2 to reconcile both functions for the purpose of therapeutics.

Behavioral skills training (BST) is effective for teaching safety skills but often requires a behavior analyst to conduct the training, which can make it costly and inaccessible for most parents or teachers. Parent-conducted BST may allow for children to receive training without the need for a trained behavior analyst. However, providing parents with training can often be difficult. Manualized training from a website could allow parents access to needed material at a low or no cost. This study evaluated a web-based manualized intervention implemented by parents for teaching firearm safety skills using BST. First, BST experts and parents validated the web-based manual. Next, we used a multiple-probe across participants design to assess the effectiveness of parent-conducted BST. Results indicate that three children acquired the safety skills after parent-conducted BST alone, and the other three children required experimenter-conducted IST. The advantages of parent-conducted BST, limitations, and areas for future research are discussed.