Children's scale errors with tools.

Children sometimes make scale errors, attempting to interact with tiny object replicas as though they were full size. Here, we demonstrate that instrumental tools provide special insight into the origins of scale errors and, moreover, into the broader nature of children's purpose-guided reasoning and behavior with objects. In Study 1, 1.5- to 3.5-year-olds made frequent scale errors with tools in a free-play session. Study 2 utilized a novel forced-choice method, representing a stronger test by handing 2-year-olds a feasible alternative for goal achievement, but children continued to make scale errors. Study 3 confirmed that errors were not based in perceptual immaturity. Results are explained using a framework of teleofunctional (purpose-based) reasoning as a powerful and early developing influence on children's actions. (PsycINFO Database Record (c) 2011 APA, all rights reserved)     

Application of the FLP/FRT system for conditional gene deletion in yeast Saccharomyces cerevisiae

The yeast Saccharomyces cerevisiae has proved to be an excellent model organism to study the function of proteins. One of the many advantages of yeast is the many genetic tools available to manipulate gene expression, but there are still limitations. To complement the many methods used to control gene expression in yeast, we have established a conditional gene deletion system by using the FLP/FRT system on yeast vectors to conditionally delete specific yeast genes. Expression of Flp recombinase, which is under the control of the GAL1 promoter, was induced by galactose, which in turn excised FRT sites flanked genes. The efficacy of this system was examined using the FRT site-flanked genes HSP104, URA3 and GFP. The pre-excision frequency of this system, which might be caused by the basal activity of the GAL1 promoter or by spontaneous recombination between FRT sites, was detected ca. 2% under the non-selecting condition. After inducing expression of Flp recombinase, the deletion efficiency achieved ca. 96% of cells in a population within 9 h. After conditional deletion of the specific gene, protein degradation and cell division then diluted out protein that was expressed from this gene prior to its excision. Most importantly, the specific protein to be deleted could be expressed under its own promoter, so that endogenous levels of protein expression were maintained prior to excision by the Flp recombinase. Therefore, this system provides a useful tool for the conditional deletion of genes in yeast.     

The farmland conversion process in a polynucleated metropolis

The conversion of farmland to urban land uses is analyzed for a study area on the fringe of Chicago (USA) for the period between 1975 and 1990. Several geographic information system databases are developed to examine the amount and quality of farmland being lost to urban development. The results show that “edge cities” are redefining the landscapes of the urban fringe where low-density residential uses are replacing prime farmland at a rapid rate. A national-level database is used to compare the Chicago area results with other large urban areas of the USA's Midwest. Most large cities of the Midwest reveal a similar pattern of development replacing prime farmland on the urban fringe.     

南波士顿海洋公园：21世纪公共空间设计

马萨诸塞港务局负责开发的南波土顿海洋公园是25万平方米闲置滨海区重新规划的核心工程之一。2004年开始运营的海洋主题公园不仅受到美国各界的广泛关注,而且荣获美国景观设计师协会颁发的国家荣誉奖。在哈文森设计事务所的带领下,景观设计师连同各学科人员共同创作出一个当代公共花园,它不仅立意鲜明大胆,而且生动地记录了该地区的百年海洋史。马萨诸塞港务局最初的目标是建设一座占地4500平方米的“主题公园”,     

Identification of cell surface markers to differentiate rat endothelial and fibroblast cells using lectin arrays and LC-ESI-MS/MS

Vascular endothelial cells located at the inner surface of blood vessels are a key component in angiogenesis and are employed as a primary cell type in the study of angiogenesis. These endothelial cells are, however, easily contaminated with fibroblast cells, which are located in proximity to the endothelial cells, during their isolation from tissue. It is thus important to find markers to distinguish the two cell types. In the present work, lectin arrays were prepared using aldehyde-terminated self-assembled monolayers (SAMs) and utilized to explore cell surface carbohydrate expression patterns on endothelial and fibroblast cells. It was found that the lectins Griffonia simplicifolia II (GS II) and Ulex europaeus agglutinin I (UEA I) selectively bind to rat fibroblast cells and not to rat endothelial cells. GS II-binding glycoproteins on fibroblast cells, which are potential cell surface markers to differentiate endothelial and fibroblast cells, were captured on a GS II lectin column and analyzed by LC-ESI-MS/MS. Six candidate cell surface glycoproteins were identified. Differential expression was confirmed by Western blot analysis for two of these proteins, lysosome-associated membrane glycoprotein-1 and transmembrane glycoprotein NMB.     

Assessment of cognitive decline through quantitative analysis of the timed up and go test

Cognitive decline and dementia have emerged as major challenges in modern healthcare with enormous associated societal and economic costs. Shifting demographics, owing to increasing numbers of people aged over 65 have greatly increased the potential scale of this problem in years to come. We report a novel quantitative method for assessment of cognitive decline (defined as a decline in mini mental state examination (MMSE) score of three or more) using quantitative parameters derived from body-worn inertial sensors. We sought to determine if baseline quantitative parameters and changes from baseline at follow-up, in those parameters could be used to automatically classify participants as cognitively declined or intact. Quantitative movement parameters were obtained at a baseline clinical assessment and in a follow-up assessment approximately 2 years later, using shank mounted triaxial gyroscopes. Data were obtained from 189 community dwelling older adults (aged over 60, 59 male, 130 female, mean age: 70.43 ± 6.57) while performing the timed up and go test. Nine participants who were deemed to be cognitively impaired at baseline (MMSE < 24) were excluded from analysis. Results suggest that quantitative parameters measured at baseline are 75.94% accurate in predicting cognitive decline in participants who were cognitively intact at baseline. A combination of baseline quantitative movement parameters and the change at follow-up (compared to baseline) in these parameters were 88.78% accurate in classifying final cognitive status in participants deemed cognitively intact at baseline. The reported method may be suitable for use as a portable cognitive screening tool, prompting further specialist clinical investigation and may also form part of a tool for longitudinal monitoring of cognitive function.     

Theoretical progress and challenges in H3+ dissociative recombination

We discuss the Jahn-Teller mechanism for dissociative recombination in low energy collisions between electrons and H3+ ions, in energy ranges relevant to the processes underway in interstellar clouds. While theory has become capable of predicting recombination rates in reasonable agreement with storage ring experiments, some discrepancies remain with them, and a long-standing discrepancy with stationary afterglow measurements remains troubling. Speculations about the desirable improvements in both theory and experiment are presented.     

A common basis for recency effects in immediate and delayed recall.

Examined the effects of word frequency and list length on the long-term serial position curve in 2 experiments, using a total of 68 undergraduates. In Exp I, the object was to find a distractor activity that would be sufficient to eliminate the recency effect in conventional free recall. In Exp II, whether list length would show a similar pattern of effects in a continuous-distractor paradigm was examined. Results demonstrate that word frequency and list length had the same effects on the serial-position curve in the continuous-distractor paradigm of delayed recall that they had previously been shown to have in immediate recall. High word frequency and shorter lists led to improved recall of preterminal items but did not influence recall of terminal items. Results suggest that the same processes underlie recency effects in the 2 paradigms and that accounts that attribute recency effects to primary (or short-term) memory are inadequate. (41 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Mechanisms of normal and abnormal neurulation: evidence from embryo culture studies

In this paper we estimate the size of several categories of "Israeli" immigrants in the United States. According to the 1990 U.S. census, there were about 95,000 Israeli-born immigrants in the United States in that year. Using the language and ancestry information available in the Public Use Microdata Sample (PUMS) of the 1990 census, we estimate that of this total, about 80,000 are Jews and 15,000 are Palestinian Arabs born in Israel. In addition to the Israeli-born, we present a range for the number of Jewish immigrants from Israel who are not Israeli-born (about 30,000-56,000). Thus our estimate for the total number of Jewish immigrants from Israel in the United States in 1990 is between 110,000 and 135,000. Fertility information available in the PUMS, also enable us to provide estimates for the number of second-generation Israelis in the United States in the 1990 (about 42,000). Finally, using both the 1980 and 1990 PUMS, we provide estimates for the rate of return migration among Israeli-born Jewish immigrants in the United States.     

Gastrulation and hatch as critical thermal windows for salmonid embryo development

Climate change and impoundment increase river temperatures, shifting the bioclimatic envelope in which freshwater biota have evolved and increasing salmonid egg mortality. To mitigate this, conservation flows from reservoirs are often implemented to maintain favourable water temperatures downstream from impoundments throughout salmonid embryo development. However, as water to maintain conservation flows becomes scarcer, there is a need to understand the requirements of salmonid embryos and balance these with anthropogenic demands. This study combines a laboratory-based and a modelling approach to test the effect of different temperatures on the survival from fertilisation to hatch of a model salmonid species. Further, the effect of dropping temperatures from high to optimal conditions at hatch—a perceived period of greater sensitivity to high temperatures—is tested. The study shows embryo mortality increases with temperature and is greatest during gastrulation and hatch. Also, embryos that experienced high temperatures during gastrulation had high mortality rates at hatch, even when hatch conditions were optimal. This indicates sublethal developmental abnormalities caused by high temperatures during gastrulation increase mortality at hatch. Therefore, to maintain high rates of salmonid embryo survival, cold water resources from reservoirs ideally will target both gastrulation and hatch developmental stages.