16 research outputs found
A comparison of childrenâs perspectives: Analyzing cultural and gender issues for preservice teachers around the world
For the past 7 years, preservice teachers in multiple countries around the world
have been involved in an international internet project designed to increase their cultural competence, improve their language and technology skills, and enhance their collaboration skills for working with diverse populations. Preservice teachers' reflections are analyzed by gender, years of experience, and outcomes related to the project that will influence their experiences
in the education field. Barriers to collaboration and solutions on how to overcome these barriers are presented in this article
Substantially improved pharmacokinetics of recombinant human butyrylcholinesterase by fusion to human serum albumin
<p>Abstract</p> <p>Background</p> <p>Human butyrylcholinesterase (huBChE) has been shown to be an effective antidote against multiple LD<sub>50 </sub>of organophosphorus compounds. A prerequisite for such use of huBChE is a prolonged circulatory half-life. This study was undertaken to produce recombinant huBChE fused to human serum albumin (hSA) and characterize the fusion protein.</p> <p>Results</p> <p>Secretion level of the fusion protein produced <it>in vitro </it>in BHK cells was ~30 mg/liter. Transgenic mice and goats generated with the fusion constructs expressed in their milk a bioactive protein at concentrations of 0.04â1.1 g/liter. BChE activity gel staining and a size exclusion chromatography (SEC)-HPLC revealed that the fusion protein consisted of predominant dimers and some monomers. The protein was confirmed to have expected molecular mass of ~150 kDa by Western blot. The purified fusion protein produced <it>in vitro </it>was injected intravenously into juvenile pigs for pharmacokinetic study. Analysis of a series of blood samples using the Ellman assay revealed a substantial enhancement of the plasma half-life of the fusion protein (~32 h) when compared with a transgenically produced huBChE preparation containing >70% tetramer (~3 h). <it>In vitro </it>nerve agent binding and inhibition experiments indicated that the fusion protein in the milk of transgenic mice had similar inhibition characteristics compared to human plasma BChE against the nerve agents tested.</p> <p>Conclusion</p> <p>Both the pharmacokinetic study and the <it>in vitro </it>nerve agent binding and inhibition assay suggested that a fusion protein retaining both properties of huBChE and hSA is produced <it>in vitro </it>and <it>in vivo</it>. The production of the fusion protein in the milk of transgenic goats provided further evidence that sufficient quantities of BChE/hSA can be produced to serve as a cost-effective and reliable source of BChE for prophylaxis and post-exposure treatment.</p
The James Webb Space Telescope Mission
Twenty-six years ago a small committee report, building on earlier studies,
expounded a compelling and poetic vision for the future of astronomy, calling
for an infrared-optimized space telescope with an aperture of at least .
With the support of their governments in the US, Europe, and Canada, 20,000
people realized that vision as the James Webb Space Telescope. A
generation of astronomers will celebrate their accomplishments for the life of
the mission, potentially as long as 20 years, and beyond. This report and the
scientific discoveries that follow are extended thank-you notes to the 20,000
team members. The telescope is working perfectly, with much better image
quality than expected. In this and accompanying papers, we give a brief
history, describe the observatory, outline its objectives and current observing
program, and discuss the inventions and people who made it possible. We cite
detailed reports on the design and the measured performance on orbit.Comment: Accepted by PASP for the special issue on The James Webb Space
Telescope Overview, 29 pages, 4 figure
The influence of season on preovulatory events associated with estrus synchronization in dwarf goats raised in Quebec /
In temperate zones most breeds of goats are anestrous and anovulatory during spring and summer, but start cycling as day length decreases during the fall. In tropical zones, indigenous goats, such as the Pygmy and the Nigerian Dwarf, tend to cycle throughout the year. Some studies have indicated that dwarf breeds become more seasonal when they are raised in temperate zones, while others maintain that they are capable of breeding throughout the year. In this study, Pygmy and Nigerian Dwarf goats became more seasonal in Quebec. The majority of the animals were cycling during December and February, but a significant proportion exhibited anestrus during October, May, and June. Several hormones, including prostaglandins (PG), progestagens, and gonadotropins (eCG, FSH, GnRH, hCG), have been used for the control and synchronization of estrus and ovulation in goats, but limited research has been conducted with dwarf breeds. In this study, dwarf goats were synchronized in November, March, and July with a 10-day MAP sponge coupled with 125 mug cloprostenol i.m. 48 h before sponge removal and 300 IU eCG i.m. at sponge removal. A seasonal shift was detected in the intervals to the onset of estrus, the LH surge, and ovulation following sponge removal. These intervals were shorter in November and July than in March (P < 0.05). The intervals between the onset of estrus and the LH surge and between the LH surge and ovulation were found constant throughout the different seasons. The administration of 50 mug GnRH at 24 h after sponge removal improved the timing and synchrony of the LH surge and ovulation in dwarf goats (P < 0.05). The knowledge acquired from this research may serve to improve reproductive efficiency in dwarf goats by facilitating the determination of an optimal time for breeding, artificial insemination, and oocyte and embryo recovery
Composition of Weight Loss In Severely Obese Women: A New Look At Old Methods
Seven severely obese, outpatient dieters lost weight (mean ± SEM, 14 ± 1 kg), and the composition of weight lost was determined by six different models. Total body water (TBW), total body potassium (TBK), and body density, bone mineral content, and fat as determined by dual photon absorptiometry (DPA) were measured while subjects were weight-stable, before and after weight loss. Fat loss was calculated by three two-compartment models (2C-TBW, 2C-TBK, and hydrodensitometry [2C-HD]), one three-compartment model (HD with correction for water content of fat-free mass (FFM], 3C), and one four-compartment model (HD with correction for water and mineral content of FFM, 4C), and was measured directly by DPA. Mean composition of weight loss was similar for all models (mean weight lost as fat: 89% for DPA, 91.5% for 4C, 89% for 3C, 88.6% for 2C-HD, and 87% for 2C-TBW) except 2C-TBK (weight lost as fat, 66%). There was a much wider range of individual values for the 2C-TBW and 2C-TBK models (17% to 138% and 18% to 93%, respectively) than for the multicompartment models (63% to 112%) and DPA (76% to 107%). Almost opposite results were obtained for the same individual when using the 2C-TBK and 2C-TBW models. The discrepancy between these models was due to the inverse relationship between changes in TBW and TBK in the group as a whole (r = - .34, NS). In addition, TBK loss was found to be dependent on the initial level of hyperinsulinemia, calculated as the area under the 2-hour oral glucose tolerance curve. In conclusion, in severely obese patients, fat-loss measurements by presently available methods are not very consistent for individuals, although group averages are similar. Individual differences are due to variable changes in body fluid and potassium compartments, and multicompartment models are recommended to correct for this
Path Dependence in Decision-Making Processes: Exploring the Impact of Complexity under Increasing Returns
The development of path-dependent processes basically refers to positive feedback in terms of increasing returns as the main driving forces of such processes. Furthermore, path dependence can be affected by context factors, such as different degrees of complexity. Up to now, it has been unclear whether and how different settings of complexity impact path-dependent processes and the probability of lock-in. In this paper we investigate the relationship between environmental complexity and path dependence by means of an experimental study. By focusing on the mode of information load and decision quality in chronological sequences, the study explores the impact of complexity on decision-making processes. The results contribute to both the development of path-dependence theory and a better understanding of decision-making behavior under conditions of positive feedback. Since previous path research has mostly applied qualitative case-study research and (to a minor part) simulations, this paper makes a further contribution by establishing an experimental approach for research on path dependence.You can play an additonal video-file that demonstrates a brief instruction to the ComPad-Explorer (see "Supplementary material" below)