Screening of monoclonal antibodies recognizing oncofetal antigens for isolation of trophoblasts from maternal blood for prenatal diagnosis

Many monoclonal antibodies have been produced against tumour-associated cell surface antigens for cancer therapy. They have therefore been selected for minimal reactivity with normal tissues and in particular for lack of binding to blood cells or serum components. Many of the antigens recognized are of fetal origin. These monoclonal antibodies may therefore be ideal candidates to recognize and sort fetal trophoblasts from maternal blood for prenatal diagnosis of genetic abnormalities. A panel of 19 anti-tumour antibodies were therefore screened for reactivity with early trimester placenta and two, 340 and 154, were shown to stain trophoblasts. If MAb 340 is linked to magnetic beads, it can efficiently sort trophoblast cell lines from whole blood.     

Predation risk and foraging behavior of the hoary marmot in Alaska

Summary I observed hoary marmots for three field seasons to determine how the distribution of food and the risk of predation influenced marmots' foraging behavior. I quantified the amount of time Marmota caligata foraged in different patches of alpine meadows and assessed the distribution and abundance of vegetation eaten by marmots in these meadows. Because marmots dig burrows and run to them when attacked by predators, marmot-toburrow distance provided an index of predation risk that could be specified for different meadow patches.Patch use correlated positively with food abundance and negatively with predation risk. However, these significant relationships disappeared when partial correlations were calculated because food abundance and risk were intercorrelated. Using multiple regression, 77.0% of the variance in patch use was explained by a combination of food abundance, refuge burrow density, and a patch's distance from the talus where sleeping burrows were located. Variations in vigilance behavior (look-ups to search for predators while feeding) according to marmots' ages, the presence of other conspecifics, and animals' proximity to their sleeping burrows all indicated that predation risk influenced foraging.In a forage-manipulation experiment, the use of forage-enhanced patches increased six-fold, verifying directly the role of food availability on patch used. Concomitant with increased feeding, however, was the intense construction of refuge burrows in experimental patches that presumably reduced the risk of feeding. Thus, I suggest that food and predation risk jointly influence patch use by hoary marmots and that both factors must be considered when modeling the foraging behavior of species that can be predator and prey simultaneously.     

Early Development of Systems Analysis in Natural Resources Management from Man and Nature to the Miami Conservancy District

Contemporary approaches to natural resources and environmental decision-making typically draw on a “systems” perspective to assess and improve management strategies. This paper describes the early genesis of the systems analysis approach. It concentrates on a period between the mid-19th to early 20th centuries. During the early part of this period, George Marsh's Man and Nature and related works laid out an approach to problem-solving that recognized the relationship among physically disperse elements in the environment, the need to balance benefits against costs, the potential for using quantitative modeling to understand management options, and the importance of integrating human and natural components into solutions. In the early 20th century, the Miami Conservancy District project brought this approach to fruition with its use of complex simulation and optimization modeling, detailed cost–benefit analysis, and its linking of economics, engineering, science, and law into a far-reaching solution to a complex water resources problem. The objective of this paper is to describe the early development and application of this conceptual approach to problem-solving. An examination of the origins of natural resources systems analysis can broaden one's perspective of the contemporary field to understand its roots as a philosophy for environmental problem-solving.     

Direct and short-term culture preparation of chorionic villi. Is any one method best?

Chorionic villi from 20 diagnostic cases were prepared for cytogenetic analysis by a direct and two short-term culture methods. No significant differences were found between the methods in the quality and quantity of metaphases obtained. A further study using villi from 20 pre-termination patients indicated an inherent variation in the quality of villi resulting in inconsistent processing and variation in the response of a sample to the methods. This suggests that it would be advantageous to process the villi by more than one method.     

Sibling recognition in thirteen-lined ground squirrels: effects of genetic relatedness,rearing association,and olfaction

Summary I investigated sibling-sibling recognition in captive thirteen-lined ground squirrels (Spermophilus tridecemlineatus) by cross-fostering lab-born pups shortly after birth. When young reached about 45 days of age, I observed dyadic interactions in a test arena of pairs from four relatedness X rearing groups, and recorded the frequency of exploratory encounters between individuals. Sibs-reared together and nonsibs-reared together exhibited significantly fewer exploratory encounters than either sibs-reared apart or nonsibsreared apart. Young reared together were equally exploratory, regadless of relatedness; similarly, young reared apart, whether they were sibs or nonsibs, showed similar levels of exploration. Thus, the differential treatment of siblings in the lab appears to be based on rearing association and not genetic relatedness per se. I interpret this recognition based on association (rearing familiarity) in the context of the species' social organization and compare my results on S. tridecemlineatus with similar studies on S. beldingi, S. parryii, and S. richardsonii. I also used an olfactory impairment technique (zinc sulfate) and found that differential treatment in thirteen-lined ground squirrels was influenced by olfactory cues.     

Staff burnout in a psychiatric hospital: A cross-lagged panel design

Previous research has shown that burnout in staff members at psychiatric hospitals is significantly associated with state anxiety and collegial support. The directionality of these relationships may be inferred using a cross-lagged panel design. To do this, 35 staff members representing various clinical disciplines completed measures of burnout, support, and anxiety twice, eight months apart. Burnout comprised three factors: emotional exhaustion, depersonalization, and personal accomplishment. Findings from one cross-lagged panel suggested that emotional exhaustion causes state anxiety. The second panel showed that lack of collegial support caused depersonalization. Understanding causes and effects of burnout for inpatient psychiatric staff may lead to training and resource development that will improve the quality of their work environment.     

Measurements of 60Co in spoons activated by neutrons during the JCO criticality accident at Tokai-mura in 1999

Neutron activated items from the vicinity of the place where the JCO criticality accident occurred have been used to determine the fluence of neutrons around the facility and in nearby residential areas. By using underground laboratories for measuring the activation products, it is possible to extend the study to also cover radionuclides with very low activities from long-lived radionuclides. The present study describes gamma-ray spectrometry measurements undertaken in a range of underground laboratories for the purpose of measuring (60)Co more than 2 years after the criticality event. The measurements show that neutron fluence determined from (60)Co activity is in agreement with previous measurements using the short-lived radionuclides (51)Cr and (59)Fe. Limits on contamination of the samples with (60)Co are evaluated and shown to not greatly affect the utility of neutron fluence determinations using (60)Co activation.     

Simulation of Halocarbon Production and Emissions and Effects on Ozone Depletion

/ This paper describes an integrated model that simulates future halocarbon production/emissions and potential ozone depletion. Applications and historical production levels for various halocarbons are discussed first. A framework is then presented for modeling future halocarbon impacts incorporating differences in underlying demands, applications, regulatory mandates, and environmental characteristics. The model is used to simulate the potential impacts of several prominent issues relating to halocarbon production, regulation, and environmental interactions, notably: changes in agricultural methyl bromide use, increases in effectiveness of bromine for ozone depletion, modifications to the elimination schedule for HCFCs, short-term expansion of CFC demand in low use compliance countries, and delays in Russian Federation compliance. Individually, each issue does not unequivocally represent a significant likely increase in long-term atmospheric halogen loading and stratospheric ozone depletion. In combination, however, these impacts could increase peak halogen concentrations and long-term integral halogen loading, resulting in higher levels of stratospheric ozone depletion and longer exposure to increased levels of UV radiation.KEY WORDS: Halocarbons; Ozone depletion; Montreal Protocol; Integrated assessment     

Predictors for people's response to a tornado warning: Arkansas, 1 March 1997

On 1 March 1997, powerful tornadoes touched down in Arkansas (USA) on a Saturday afternoon. Twenty-six fatalities and 400 non-fatal injuries were reported. We performed a population-based cross-sectional study to determine factors associated with appropriate responses to tornado warnings. Of 146 survey participants, 140 (96 per cent) knew the difference between 'tornado watch' and 'tornado warning' and were aware of when the warning was announced. Of those 140 participants, 64 (45.7 per cent) responded to the warning by seeking shelter, and 58 (90.6 per cent) of those 64 acted within five minutes of hearing the warning. Four factors were positively associated with those seeking shelter: having graduated from high school (OR = 4.2, 95 per cent CI = 1.1-15.5); having a basement in one's house (OR = 3.8, 95 per cent exact CI = 1.1-17.1); hearing a siren (OR = 4.4, 95 per cent CI = 1.3-18.9); and having prepared a household plan of response when tornadoes occur (OR = 2.6, 95 per cent CI = 1.1-6.3). On the basis of these findings, we recommend: first, that people who live in tornadoprone areas have a personal plan of action to help them respond immediately to warnings; second, public-health education officials in areas with frequent tornadic activity should do more to educate the public about what they can do to protect themselves from a tornado; and third, that emergency-management officials planning protection measures for vulnerable communities should consider that most people have limited time (our study documented five minutes) in which to respond to a tornado warning. Thus, shelters in tornado-prone areas should be quickly accessible by residents.     

Consumer Choice and Farmers’ Markets

The increasing popularity of local food consumption can be attributed to the heightened awareness of food safety concerns, carbon emissions produced from food transportation, and an understanding of how large corporations’ obtain their food supplies. Although there is increasing discussion on both the local and organic food movement independently, there is not a wide availability of literature examining the motivations and perceptions of consumers with regard to farmers’ markets. Issues such as perceptions about what type of food consumers are purchasing at markets, nor the main motivations for frequenting such establishments are discussed. Therefore the purpose of this study was to determine consumer motivations, benefits, and perceptions of farmers’ markets. Using the case study location of Toronto, Canada, this study surveyed 300 participants during the fall of 2011. Findings indicated that the main purpose for visiting famers’ markets is not solely to fulfill grocery needs. Quality of products offered and the ability to support the local community were the primary motivators to visit the markets.