Uterine cavity lavage: Adding fish to conventional cytogenetics for embryonic sexing and diagnosing common chromosomal aberrations

This study was undertaken to examine the efficacy for early prenatal diagnosis of uterine cavity lavage at the level of the internal os and to assess the rate of maternal contamination. In phase I, uterine cavity lavage was performed in 38 women scheduled for pregnancy termination between 6 and 12 weeks. In addition to short- and long-term cultures, one-colour FISH (fluorescence in situ hybridization) with Y and X probes was used for fetal sexing. Two-colour FISH was used in all known male fetuses for the assessment of maternal contamination. In phase II, lavage was performed on 16 women. Fetal sex was diagnosed with direct labelled X and Y probes and common numerical chromosomal aberration was attempted with 18 and 21 direct labelled probes. Fetal sexing was successful in all cases in phases I and II. Out of 34 patients in which tissue was obtained, only FISH was done in six. Long-term cell cultures were successful in the other 28 cases, but complete karyotyping in 19 (56 per cent). No chromosomal aberration was found with the direct labelled probes 18 and 21 in FISH. Maternal contamination was assessed to be 5–10 per cent. This simple and easy-to-master technique is very effective in obtaining fetal cells early in pregnancy for genetic diagnosis, especially by FISH. However, the safety of the procedure must be tested in ongoing pregnancies.     

Inflation of subordinates' performance ratings: main and interactive effects of rater negative affectivity,documentation of work behavior,and appraisal visibility

We hypothesized that raters' tendency to deliberately inflate performance appraisal ratings of subordinates would be associated with rater negative affectivity (NA) and two characteristics of the performance appraisal context: documentation of subordinates' work behaviors and appraisal visibility. We further hypothesized interactions among these variables, such that high‐NA, but not low‐NA raters, would be more likely to inflate ratings under conditions of low documentation and high appraisal visibility. Moreover, we predicted that NA would be associated most strongly with rating inflation when documentation was low and appraisal visibility was high, simultaneously. Results from a sample of 148 supervisors from a variety of organizations supported these hypotheses. We discuss several practical implications of the results and suggest areas for future inquiry. Copyright © 1999 John Wiley & Sons, Ltd.     

Limiting the impact of light pollution on human health, environment and stellar visibility

Light pollution is one of the most rapidly increasing types of environmental degradation. Its levels have been growing exponentially over the natural nocturnal lighting levels provided by starlight and moonlight. To limit this pollution several effective practices have been defined: the use of shielding on lighting fixture to prevent direct upward light, particularly at low angles above the horizon; no over lighting, i.e. avoid using higher lighting levels than strictly needed for the task, constraining illumination to the area where it is needed and the time it will be used. Nevertheless, even after the best control of the light distribution is reached and when the proper quantity of light is used, some upward light emission remains, due to reflections from the lit surfaces and atmospheric scatter. The environmental impact of this "residual light pollution", cannot be neglected and should be limited too. Here we propose a new way to limit the effects of this residual light pollution on wildlife, human health and stellar visibility. We performed analysis of the spectra of common types of lamps for external use, including the new LEDs. We evaluated their emissions relative to the spectral response functions of human eye photoreceptors, in the photopic, scotopic and the 'meltopic' melatonin suppressing bands. We found that the amount of pollution is strongly dependent on the spectral characteristics of the lamps, with the more environmentally friendly lamps being low pressure sodium, followed by high pressure sodium. Most polluting are the lamps with a strong blue emission, like Metal Halide and white LEDs. Migration from the now widely used sodium lamps to white lamps (MH and LEDs) would produce an increase of pollution in the scotopic and melatonin suppression bands of more than five times the present levels, supposing the same photopic installed flux. This increase will exacerbate known and possible unknown effects of light pollution on human health, environment and on visual perception of the Universe by humans. We present quantitative criteria to evaluate the lamps based on their spectral emissions and we suggest regulatory limits for future lighting.     

Urban hinterlands—the case of an Israeli town ecological footprint

Modern urban life is characterized by the consumption of materials and energy, which are imported from all over the world and discharge waste that in many cases has a negative impact on ecosystems far from the cities in which they consumed. Indeed, cities cannot survive without worldwide hinterlands for resources and emissions sequestration. The ecological footprint (EF) concept provides valuable insights into the human appropriation of resources relative to earth’s carrying capacity, and therefore it enables us to compare human demands with nature’s supply and provides an indicator of human ecological sustainability. An attempt was made to calculate the EF of Ra’anana, Israel as a case study, to compare the EF-value with the expected for ecological sustainability and to emphasize the dependence on overseas ecosystems. Ra’anana, a town of 67,300 inhabitants in the year 2002, is considered a ‘dormitory town’ with a high quality of life. The EF was calculated using mainly the component method. The calculated EF for Ra’anana is 4.0 ha/resident which means that the required hinterland, located all over the world, is nearly 180 times the size of the town. The town’s EF is twice the value expected for sustainability on a global scale. We draw several scenarios in order to reduce the EF. On a national basis as well as with the town case study, electric energy, food and waste can be reduced and in turn would have a dramatic impact on the EF.

Neutralization of an extremely acidic sludge and stabilization of heavy metals in flyash aggregates

An extremely acidic, heavy metal-rich sludge (pH=-1.2) was scrubbed with a Class-F fly ash in order to simultaneously neutralize the acidity and stabilize the heavy metals contained in both wastes. This paper outlines the leaching behavior of the aggregate material generated by scrubbing. For proper fly ash/sludge ratios, the fly ash acted as an outstanding neutralizer for the acidic waste. Leaching of heavy metals from the aggregate samples was below the environmental limits within a pH range between 3 and 9. Subsequent washing of the leached aggregate with acidic CALWET solutions did not result in an additional release of heavy metals. It is proposed that coordinative bonding of the metal cations onto neutral surface sites and electrostatic adsorption led to stabilization of the heavy metals within the aggregate structure below hydrolysis pHs.     

The democratic provision of public and private goods from exhaustible resources

The problem of distributing exhaustible natural resources between consumption goods and environmental amenities through a voting process is analyzed. Assuming that individuals are endowed with an equal share of private goods, the method of majority decision does not always achieve a Pareto-optimal distribution. However, by means of side payments, the intensity of preferences is revealed. The voting procedure then leads to a Pareto-optimal solution which is more prone to environmental amenities than the simple method of majority decision.     

On the optimal allocation of pesticides with increasing resistance: The case of alfalfa weevil

The problem of pesticide application under increasing pesticide resistance is explored. A theoretical model is developed to determine optimal pesticide use. This allocation is compared to the laissez-faire solution and to the centralized solution with incomplete information about pesticide resistance. The methodology is then applied in a case study on the Egyptian alfalfa weevil in California.