Measurements of mass and momentum flux in non-ideal molecular beams

Momentum transfer and mass determinations for nonideal molecular beam - fluid mechanic

Altered Human Neutrophil Function in Response to Acute Psychological Stress

Objective: To examine the effects of an acute laboratory psychological stress task on neutrophil function, specifically phagocytosis of Escherichia coli and stimulated superoxide production in human neutrophils. There is mounting evidence that acute stress is associated with short-term increases in a number of immune indices. \ud \ud Methods: Participants were 40 (n = 20 females) university students (mean age, 25.9 ± 4.56 years). Blood samples to determine neutrophil function by flow cytometry were taken at the end of resting baseline, during an acute stress task, and during recovery. The stress task was a 10-minute time-pressured mental arithmetic challenge with social evaluation. \ud \ud Results: There was an acute increase in phagocytic ability, $\rho$ = .047, η2p = 0.076, and a reduction of superoxide production, p = .026, η2p = 0.101, associated with the stress task relative to baseline. \ud \ud Conclusion: These findings suggest that neutrophil bactericidal function may be sensitive to mental challenge tasks that provoke acute psychological stress. Further research is needed to replicate the observed psychological stress-induced changes in neutrophil function. \ud \u

Development and evaluation of lessons for class and group situations in grade I. Volume I.

Thesis (Ed.M.)--Boston University For volume II, please see: http://hdl.handle.net/2144/1415

Effectiveness of the ADEC as a level 2 screening test for young children with suspected autism spectrum disorders in a clinical setting

Background The Autism Detection in Early Childhood (ADEC) is a clinician-administered, Level 2 screening tool. A retrospective file audit was used to investigate its clinical effectiveness. Method Toddlers referred to an Australian child development service between 2008 and 2010 (N?=?53, M age?=?32.2 months) were screened with the ADEC. Their medical records were reviewed in 2013 when their mean age was 74.5 months, and the original ADEC screening results were compared with later diagnostic outcomes. Results The ADEC had good sensitivity (87.5%) and moderate specificity (62%). Three behaviours predicted autism spectrum disorders (ASDs): response to name, gaze switching, and gaze monitoring (p???.001). Conclusions The ADEC shows promise as a screening tool that can discriminate between young children with ASDs and those who have specific communication disorders or developmental delays that persist into middle childhood but who do not meet the criteria for ASDs

The Infrared Absorption Spectrum of Carbon Suboxide

The infrared absorption spectrum of carbon suboxide vapor has been studied under low dispersion in the region from 2μ to 25μ. The vibrational bands observed may be satisfactorily accounted for on the basis of a linear symmetric structure for the carbon suboxide molecule, in agreement with evidence obtained from Raman spectra and from electron diffraction investigations.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/71281/2/JCPSA6-5-8-642-1.pd

Orbital assembly and maintenance study

The requirements, conceptual design, tradeoffs, procedures, and techniques for orbital assembly of the support structure of the microwave power transmission system and the radio astronomy telescope are described. Thermal and stress analyses, packaging, alignment, and subsystems requirements are included along with manned vs. automated and transportation tradeoffs. Technical and operational concepts for the manned and automated maintenance of satellites were investigated and further developed results are presented

Depressive symptoms and quality of life in people with age-related macular degeneration

Purpose: To examine quality of life and associated factors in people with Age-Related Macular Degeneration (AMD). Methods: One hundred and forty-five AMD participants (mean age 78.0 +/- 7.7 years) and 104 age- and gender- matched controls (mean age 78.1 +/- 5.8 years) comprised the study populations for this case-control study. Depressive symptoms were measured with the Goldberg Anxiety and Depression (GAD) scale; general health and daily functioning was assessed with the Medical Outcomes Study Short Form 36 (SF-36) and questions relating to assistance required for daily living activities. Results: People with AMD performed more poorly than controls on the GAD depression scale, and physical functioning subscale of SF-36. 44.4% of people with AMD had clinically significant depressive symptoms compared to 17.5% of controls (p < 0.001). Multiple regression analysis revealed that AMD was independently associated with depressive symptoms and a path model indicated that AMD led to depressive symptoms both directly and indirectly via reduced general health and social functioning. Conclusion: Psychological and functional outcome measures are reduced in people with AMD. Earlier recognition and treatment of depressive symptoms in people with AMD may be crucial to maintaining quality of life in this group

Linear oscillations of a compressible hemispherical bubble on a solid substrate

The linear natural and forced oscillations of a hemispherical bubble on a solid substrate are under theoretical consideration. The contact line dynamics is taken into account with the Hocking condition, which eventually leads to interaction of the shape and volume oscillations. Resonant phenomena, mostly pronounced for the bubble with the fixed contact line or with the fixed contact angle, are found out. The limiting case of weakly compressible bubble is studied. The general criterion identifying whether the compressibility of a bubble can be neglected is obtained.Comment: new slightly extended version with some minor changes, added journal reference and DOI information; 12 pages, 8 figures, published in Physics of Fluid

Orbital assembly and maintenance study. Executive summary

A sound, practical approach for the assembly and maintenance of very large structures in space is presented. The methods and approaches for assembling two large structures are examined. The maintenance objectives include the investigation of methods to maintain five geosynchronous satellites. The two assembly examples are a 200-meter-diameter radio astronomy telescope and a 1,000-meter-diameter microwave power transmission system. The radio astronomy telescope operates at an 8,000-mile altitude and receives RF signals from space. The microwave power transmission system is part of a solar power satellite that will be used to transmit converted solar energy to microwave ground receivers. Illustrations are included

A probabilistic framework for forward model-driven SHM

A challenge for many structural health monitoring (SHM) technologies is the lack of available damage state data. This problem arises due to cost implications of damaging a structure in addition to issues associated with the feasibility and safety of testing a structure in multiple damage scenarios. Many data-driven approaches to SHM are successful when the appropriate damage state data is available, however the problem of obtaining data for various damage states of interest restricts their use in industry. Forward model-driven approaches to SHM seek to aid this challenge. This methodology uses validated physical models to generate predictions of the system at different damage states, providing machine learning strategies with training data, to infer decision bounds. An ideal forward model-driven SHM framework is one in which one or more physical models are able to produce predictions that are statistically representative of data obtained from the physical structure. Validation of these physical models requires observational data. As a result, validation is performed on a component or sub-system level where damage state data can be more easily obtained. This methodology requires the combination of several low-level physical models via a multi-level uncertainty integration technique. This paper outlines such a framework using uncertainty quantification technologies and statistical methods for combining low-level probabilistic models whilst accounting of discrepancies that may occur in interactions with other low-level models. The method contains several statistical techniques for accounting for model discrepancies that may occur at any point throughout the modelling process. Model discrepancies arise due to missing physics or simplifications and result in the model deviating from the observed physics even when the ‘true’ parameters of the model are known. By accounting for model discrepancies throughout the framework the approach allows for further insight into model form errors whilst also improving the techniques ability to produce statistically representative predictions across damage states. The paper presents the key stages highlighting the relevant technologies and application considerations. Additionally, a discussion of integration with current data-driven approaches and the appropriate machine learning tools is given for a forward model-driven SHM approach