Phonological Priming In Young Children Who Stutter: Holistic Versus Incremental Processing

Purpose: To investigate the holistic versus incremental phonological encoding processes of young children who stutter (CWS; N = 26) and age- and gender-matched children who do not stutter (CWNS; N = 26) via a picture-naming auditory priming paradigm. Method: Children named pictures during 3 auditory priming conditions: neutral, holistic, and incremental. Speech reaction time (SRT) was measured from the onset of picture presentation to the onset of participant response. Results: CWNS shifted from being significantly faster in the holistic priming condition to being significantly faster in the incremental priming condition from 3 to 5 years of age. In contrast, the majority of 3- and 5-year-old CWS continued to exhibit faster SRT in the holistic than the incremental condition. Conclusion: CWS are delayed in making the developmental shift in phonological encoding from holistic to incremental processing, a delay that may contribute to their difficulties establishing fluent speech.Communication Sciences and Disorder

THE INFLUENCE OF FULVIC ACID ON COPPER(II), CADMIUM(II) AND ZINC(II) REMOVAL FROM DRINKING WATER BY ALUM COAGULATION AND COPPER(II) AND CADMIUM(II) COMPLEXING CAPACITY MEASUREMENTS OF FULVIC ACID AND NATURAL FRESHWATER SAMPLES BY DIALYSIS TITRATION

The metal ion complexing chemistry of organic ligands commonly found in drinking water sources is the object of the studies in this dissertation. These ligands, called humics as a class, were modelled in some cases by a soil-derived humic material called fulvic acid. The role of natural humics in the transport and speciation of dissolved metal ions in drinking water sources, particularly health hazards like Cd(\u272+), is investigated. Some properties of soil-derived fulvic acid (SFA) were also elucidated. One study modelled a drinking water clarification and decolorizing process using aluminum hydroxide coagulation to measure Cd(\u272+), Zn(\u272+) and Cu(\u272+) removal from solution by the coagulation treatment. The effect of SFA on these metal ion removals was determined in a statistically designed experiment where the relative effects of changing metal ion concentration, Al(\u273+) concentration, solution pH, and SFA concentration on metal ion removal were revealed. Over the variable levels used in the experiment, increasing pH from 5 to 7, and increasing Al(\u273+) dosage caused the greatest overall increase in Cu(\u272+), Cd(\u272+) and Zn(\u272+) removal. Fulvic acid, representing naturally-occurring humics, aided metal ion removal when enough aluminum coagulant was used to remove all dissolved fulvic acid. When insufficient coagulant was used and some fulvic acid remained in solution, the humic material stabilized dissolved metal ions by formation of a soluble metal ion complex and resolubilized metal ions ordinarily coprecipitated with the aluminum hydroxide floc. Cu(\u272+) is very effectively removed on average (\u3e 90%) under the experimental conditions, but Cd(\u272+) and Zn(\u272+) are not (\u3c 20%). To perform the metal ion removal experiment, and to filter natural water samples with no substantial metal ion losses due to wall effects or contaminations, a microfilter apparatus was assembled and evaluated. The apparatus has all plastic surfaces for solution contact and allows vacuum filtration directly into a polypropylene receiving vessel, thereby eliminating the need for a filter flask. Cu(\u272+) losses and contaminations during filtration of standard Cu(\u272+) solutions through the plastic filter apparatus or a glass filter support, with cellulose acetate or polycarbonate filter membranes, were measured in a statistically designed experiment. The results show small Cu(\u272+) losses with the plastic filter support and either membrane (0-13% losses) compared to the glass support with either membrane (25-79% losses). The use of an all plastic filter apparatus for the filtration of natural water samples is recommended to minimize changes to the native levels of dissolved metal ions. A dialysis separation technique, where complexed and unbound metal ions are distinguished in the determination of natural freshwater metal ion binding capacities, was evaluated in another study. The dialysis technique metal ion binding results could not be distinguished from potentiometric titration results in a statistical comparison of the two methods. Nomenclature to describe metal ion binding in natural water systems was suggested. A brief literature survey of metal ion binding studies was described. The dialysis technique was applied to the measurement of 6.25 (mu)M EDTA, 15.5 (mu)M SFA and seven natural water sample capacities of Cu(\u272+) and Cd(\u272+) complexation. The metal ion binding capacities of SFA increased with pH and Cu(\u272+)-SFA capacities were greater than Cd(\u272+)-SFA capacities at the same pH. The Cu(\u272+) binding ability of the natural water samples correlates negatively with their alkalinity, pH, hardness and conductance. Cd(\u272+) binding capacities did not correlate well with any water sample characteristic

Smallholders' Cost Efficiency in Mozambique: Implications for Improved Maize Seed Adoption

Maize is an important staple in Mozambique. It is also a dominant crop produced by smallholder farmers. However, the actual maize yields, currently estimated at 1.4 tons/ha, fall short of potential yields of 5-6.5 tons/ha. With population growth rate increasingly exceeding agricultural (and maize) productivity growth rate, the government of Mozambique faces a serious problem of food insecurity and poverty alleviation. This study examines cost inefficiency among smallholder maize farmers in Mozambique, and the impact of improved maize seed adoption on cost efficiency. A Translog functional form is used to estimate the frontier cost function. A cost-inefficiency function is used to examine the factors that determine cost inefficiency among farmers. Econometric techniques to control for self-selection bias resulting from endogeneity of the adoption variable are used.stochastic frontier, technology adoption, selection bias, Mozambique, Crop Production/Industries, Q12, Q16, D13, O33,

Print quality for air photo interpretation

Thesis (M.A.)--Boston UniversitySummary: An experiment is described in which military photo interpreters select between stereographs on the basis of information content. The 16 stereographs used were all printed from the same pair of negatives of scale 1:8,400. Each stereograph was printed differently to emphasize one or more of 13 targets in the scene. The interpreters viewed individual targets in each stereograph through an Abrams CF-8 stereoscope and recorded their choice on a questionnaire. A choice was also made for overall appearance without using the stereoscope. The results from 35 observations are: Comparison Preference Preference Percent (Averaged from N targets) Light Transparency Light Transparency 100 vs. Light Transparency Dark Transparency Light Print Light Print 93 vs. Dark Print Transparency Transparency 81 vs. Print Higher Gradient Higher Gradient 80 vs. Lower Gradient (Within similar density ranges) - - - - - - - - - - - - - - - - - - - - - - *USAF Institute of 1echnology with duty station at Boston University Institute of Aerial Photography. This thesis work was supported under Contract AF 33(166)-21. Collimated Light Collimated Light 74 Printing vs. Diffuse Light Printing Eastman Variable Eastman Variable 66 Contrast Contrast vs. DuPont Varigam Unferrotyped Unferrotyped Glossy 59 Glossy Surface Surface vs. Ferrotyped Glossy Surface It is concluded that for gaining intormation under the conditions of this study military photo interpreters show: 1. Strong preference for positive transparencies instead of positive paper prints. 2. Strong preference tor positives which were printed from collimated light instead of positives printed from diffuse light. 3. Strong preference for lighter appearing instead or darker appearing positives; providing the details are neither "washed out" nor '"blocked up." There is a tendeney for very light "washed out highlights" to be accepted while "'blocked up shadows" are rejected. 4. Strong preference for positive material D-Log E Curve gradients which are higher instead of lower for the same general range of densities in the positive. 5. Moderate preference for prints made on Eastman Variable Contrast Paper (Experimental Emulsion 47763A) inetead of prints made on DuPont Varigam when both are printed with ultraviolet light for use in the toe region or their respective D-Log E curves. This does not mean that DuPont Varigam paper is unacceptable. The Eastman paper has the advantage of reaching the same Dmax for all contrasts, and of having the same directional color response as Varigam. 6. Only a slight preference for unglossed surface prints instead of glossy surface prints. The conclusions would seem to warrant expenditure of time and effort toward: 1. Development of suitable equipment for viewing positive transparencies in stereo without cutting individual frames fromm the roll. 2. Study the feasibility of using: a. Variable contrast positive transparency in roll form. b. Only variable contrast paper for continuous tone printing (instead of papers of separate contrasts). 3. Supplying a summary of the information in this report regarding the photo interpreter's preferences in Technical Order form to appropriate photofinishing agencies

Unit organization of the topic history of labor in the United States.

Thesis (Ed.M.)--Boston Universit

Wellness programs and administrative procedures: implications for teacher use of short term sick leave in Iowa schools

This study was conducted to determine the selected factors which affected teacher use of short term sick leave in Iowa public school districts from 1980 through 1989. The selected factors were grouped into two categories, wellness programs and administrative procedures;The seven selected factors in the wellness category include exercise programs, incentives, medical screening, nutrition programs, lifestyle management programs, fitness assessment, and a wellness newsletter. The six selected factors in the administrative procedure category include teachers calling their supervisor when ill, attendance as part of evaluation, district policy on teacher attendance, attendance monitoring systems, incentives for positive attendance, and positive feedback on teacher attenDance;;As a related aspect of this study, several other factors were analyzed to determine any influence on teacher use of sick leave. These factors included the size of district, the health insurance carrier, and a rebate given to the school district by the health insurance carrier;Four hundred thirty-one questionnaires were distributed to superintendents and wellness coordinators in Iowa public schools. The questionnaires were intended to determine use of wellness activities, administrative procedures, and the number of short term teacher sick days used in each district. The short term sick days were calculated by subtracting from the total district teacher sick days all teacher sick days of 30 or more consecutive days accumulated for any teacher(s);Analyses of the data indicate that only those districts which offered lifestyle management programs affected the use of short term teacher sick leave. This study was unable to identify a significant relationship between any of the other factors and teacher use of short term sick leave