Understanding and controlling the ingress of driven rain through exposed, solid wall masonry structures

Long term performance of historic buildings can be affected by many environmental factors, some of which become more apparent as the competence of the fabric deteriorates. Many tall historic buildings suffer from water ingress when exposed to driving rain conditions, particularly church towers in the south west of England. It is important to recognise that leakage can occur not only through flaws in the roof of a building but also through significant thicknesses of solid masonry. Identification of the most appropriate intervention requires an understanding of the way in which water might enter the structure and the assessment of potential repair options. While the full work schedule used an integrated assessment involving laboratory, field and archival work to assess the repairs which might be undertaken on these solid wall structures, this paper focuses on the laboratory work done to inform the writing of a Technical Advice Note on the effects of wind driven rain and moisture movement in historic structures (English Heritage, 2012). The laboratory work showed that grouting and rendering was effective at reducing water penetration without retarding drying rates, but that use of internal plastering also had a very beneficial effect

Defining the Chaperone’s Role as Escort, Educator or Parent

The concept of family learning in museums emphasizes the interaction between related adults and children through the process of free-choice learning. The complexity of family learning in the context of school visits presents new questions for museum staff on the role of chaperones and the extent to which chaperone-led groups might function as family units. Do chaperones operate as escorts, educators, or parents on a museum field trip? This article provides a brief overview of existing field trip and chaperone research findings, raises some critical questions on the role of parents as chaperones, and describes the results from a study on chaperone behavior in the museum. Results from observations of 289 chaperones in a children's museum setting suggest that chaperone behavior is not necessarily influenced by exhibition context, but parents and chaperones do differ in preferred family learning interactions with children in museum exhibitions

Defining the Scope of Your Evaluation

One challenge of conducting evaluations is finding the right questions to guide the work. A clear purpose for a study gives the evaluator a good sense of what information can answer the questions, and helps frame the scope of the project as a whole. Knowing the scope of the evaluation project provides a sense of the resources needed. A common pitfall for those getting started with evaluation is trying to carry out a project before thinking about the overall purpose of the evaluation. This article provides a brief overview of defining clear and concise evaluation questions and thinking about the overall scope of an evaluation project. Examples include questions and strategies used in small, medium, and large-scale studies

Novel Role for a Neurotrophic Factor in White Adipose Tissue

Neurotrophic factors are a family of growth factors that regulate neuronal plasticity. Thus far, these factors have been understudied in peripheral tissues, including adipose tissues, where they could play a key role in mediating the neuronal inputs that lead to energy expenditure via lipolysis (white fat) and thermogenesis (brown fat). Based on prior experiments, we hypothesized that brain derived neurotrophic factor (BDNF) is the main neurotrophic factor acting in adipose tissues to mediate neurite outgrowth and branching of incoming sympathetic nerves. We found that BDNF knock-out animals had less innervation of their white fat, shown by reduced expression of neuronal markers, but a paradoxical increase in cold-stimulated brown adipogenesis in white fat (‘browning’). Further investigation using immunofluorescent staining indicates that although browning can be activated by some alternate factor that remains ambigious, innervation and stimulation of the sympathetic nervous system is required for activation of UCP1- mediated thermogenesis

DEVELOPMENT AND EVALUATION OF AN ENRICHMENT CULTURE FOR BIOAUGMENTATION OF THE P-AREA CHLORINATED ETHENE PLUME AT THE SAVANNAH RIVER SITE

The Twin Lakes chlorinated ethene plume at the Department of Energy\u27s Savannah River Site (SRS) emerges in a wetland in which trichloroethene (TCE) is completely reduced to ethene and ethane. Novel strains of Dehalococcoides have been detected from the wetland area. The objectives of this study were 1) to develop an enrichment culture capable of completely dechlorinating TCE and tetrachloroethene (PCE) to ethene using samples from the wetland; 2) to evaluate the use of lactate, emulsified vegetable oil and corn syrup as possible electron donors for biostimulation of the P-area chlorinated ethene plume at SRS that is not undergoing natural attenuation; and 3) to evaluate the use of the enrichment culture for bioaugmentation of the P-area chlorinated ethene plume. The enrichment culture was started with samples from microcosms that were used to confirm reductive dechlorination activity in the SRS Twin Lakes area. Samples were transferred to an anaerobic mineral medium, repeatedly fed with TCE and PCE, and transferred a second time to mineral medium. TCE and PCE concentrations of 35-40 mg/L and 4-8 mg/L, respectively, were completely consumed by the enrichment culture within three to five weeks. Quantitative polymerase chain reaction (PCR) analysis indicated a linear increase in Dehalococcoides as increasing amounts of PCE and TCE are reduced to ethene. The Dehalococcoides cell density in the enrichment culture has stabilized at approximately 4.5 x 108 cells per mL. Lactate was used as the electron donor and carbon source. An electron donor balance indicated that most of the lactate is iv fermented to acetate and propionate, with less than 3% used for reductive dechlorination. Methanogenesis in the enrichment culture is insignificant. A laboratory study was conducted to compare biostimulation and bioaugmentation for removal of PCE and TCE from the SRS P-area plume. Microcosms were prepared with sediment and groundwater from the site, at PCE and TCE concentrations close to the reported maxima of 5 mg/L and 35 mg/L, respectively. The pH of the groundwater was adjusted from 5.7 to 7 with NaOH and resazurin was added as a redox indicator. Lactate, corn syrup and emulsified vegetable oil were used for biostimulation. Bioaugmentation was assessed using varying doses of the SRS enrichment culture (1.0, 0.1, 0.01, and 0.001% v/v), along with one treatment using a commercial bioaugmentation culture (1.0% v/v). After more than eight months of incubation, there was no evidence of PCE or TCE dechlorination in any of the biostimulated treatments, even though the amount of donor added was in considerable excess and redox and pH conditions were favorable. The microcosms were bioaugmented after three months of incubation (to establish favorable redox conditions) and the response was immediate. In the treatment that received the 1.0% dose of SRS culture, reduction of the PCE and TCE to ethene was completed in approximately three weeks. The lower doses of SRS culture were also effective, although up to seven months of incubation was needed before dechlorination was complete. In contrast, dechlorination of PCE and TCE was much slower and incomplete in the treatment that received the commercial bioaugmentation culture, over the same incubation period. The microcosm results indicate that the SRS enrichment culture holds promise for use in v bioaugmentation of the P-area groundwater plume. Efforts are underway to scale up the enrichment culture in preparation for a pilot-scale field test

Electropalatographic Study of Speech Sound Errors in Adults with Acquired Aphasia

Traditionally speech errors in adults with acquired aphasia have been described as either apraxic errors, characteristic of anterior lesions in the cerebral cortex affecting areas such as Broca's area, or phonemic paraphasic errors due to posterior lesions in areas such as Wernicke’s area. However, studies have reported overlap in the descriptions of apraxic and phonemic paraphasic errors despite the assumption that these errors arise from different levels in the speech planning and execution process. For example, phonemic substitutions are associated with both types of error. Part of the problem is due to difficulties in identifying the precise nature and source of the errors which cannot be resolved by auditory perceptual judgements alone. This study investigates, by means of elcctropalatography (EPG), the location and timing of contact patterns produced by ten adults with acquired aphasia. The subjects were variously diagnosed by traditional classification as Broca’s aphasic with or without apraxia, conduction and anomic. These subjects variously demonstrated atypical patterns when compared to ten control speakers such as: increased temporal and/or spatial variability; specific difficulties in the sequencing and timing of two adjacent lingual consonants; and the presence of intrusive lingual/palatal contact patterns. These errors were usually undetected through auditory analysis. The atypical patterns were not associated uniquely with a particular aphasic syndrome but were subject specific and often related to the site of the lesion within the brain, for example, the basal ganglia. Both subjects diagnosed with apraxia of speech and those with phonemic paraphasia produced the EPG patterns noted above. The EPG data provided insights into the nature and origins of errors such as substitutions which were unavailable from auditory-based analysis. Many of these error patterns could be accounted for by modification to Dell’s model of spreading activation (Dell, 1980, 1985, 1986, 1990). The results have important implications for therapeutic intervention since accurate diagnosis is crucial for effective intervention

Tests for the prediction of reading success and reading failure on the primary level ..

Typewritten sheets in cover. Thesis (M.A.)--Boston University This item was digitized by the Internet Archive. Bibliography: p. 60-63

Quantification of Dye Degradation on Titanium Dioxide-Based Membranes

The purpose of this study was to examine the dye degradation on the titanium dioxide (TiO2)-based membranes. While many studies have shown photocatalytic degradation of dye on TiO2 in solution, few studies have been reported on the solid TiO2 substrate. In this work, a new method is developed to quantify the dye degradation on TiO2-based membranes. A hydrothermal method is used to synthesize the photocatalytic TiO2 nanofibers; vacuum filtration is applied to fabricate a self-assembled membrane. Silver is incorporated into the nanofibers through in situ reduction before vacuum filtration to fabricate Ag/TiO2 membrane in an attempt to red shift the material’s photoactive range; however, oxidized Ag species, such as Ag2O and AgOH, are likely incorporated due to the nanofibers’ basic environment. The catalytic properties of TiO2 and Ag/TiO2 membranes are then evaluated by the dye – methylene blue degradation under different conditions. A digital method by coupling the image-capturing method using a Gel Imaging System and the analysis using ImageJ has been standardized to monitor the dye degradation over time on the membranes. This study successfully calibrates the linear region (0 – 72.3 ng) of methylene blue drop cast on the membranes. The color intensity of two methylene blue droplets’ mass (36.3 ng and 49.6 ng) is traced under dark and light conditions. The dye degradation on the membranes follows 1st order reaction kinetics while dye degrades faster on the Ag/TiO2 membrane than the TiO2 membrane. This method may potentially be used to quantify other dye degradation on the semiconductor membranes in an effort to develop (photo)catalysts for applications such as water treatment