Ecdysone-induced puffing inDrosophila: A model

In the salivary glands ofDrosophila different sets of proteins are synthesized during two successive developmental stages. This reprogramming is controlled by the hormone ecdysone. The results presented allow a proposal for its possible mode of action.     

Inter-municipal cooperation for wastewater treatment: case studies from Israel

Since the beginning of the 1990s, local authorities in Israel have been engaged in promoting advanced Wastewater Treatment Plant (WWTP) projects throughout the country, resulting in the "wastewater treatment revolution" of the 1990s. These achievements are extremely important in the water-scarce country, as untreated or partially treated wastewater has become a major source of pollution of Israel's fresh-water resources, and reuse of high-quality effluents can expand the national water potential. Many of these projects are regional schemes based on a central WWTP, serving a few neighboring municipalities. This paper presents two case studies of such regional cooperation: the "Karmiel Region Union of Towns for Sewage Treatment" and the "Treatment and Reuse of Wastewater in the area of the Hadera Stream, Ltd." corporation. The findings suggest that regional cooperation can be an efficient tool in promoting advanced wastewater treatment, and has several advantages: an efficient use of limited resources (financial and land); balancing disparities between municipalities (size, socio-economic features, consciousness and ability of local leaders); and reducing spillover effects. However, some problems were reported in both cases and should be addressed.     

CHEMISTRY RESPONSE OF TWO FORESTED WATERSHEDS TO ACID ATMOSPHERIC DEPOSITION1

ABSTRACT: The deposition and chemistry of precipitation were estimated for one year in two forest ecosystems in the South-Central United States. Precipitation, throughfall, litter leachate, and soil leachate were analyzed for a small catchment of pine-hardwoods in southeastern Oklahoma and for a catchment of loblolly pines (Pinus taeda L.) in northern Mississippi. In the pine-hardwood forest, 98 percent of the acid deposition was neutralized, 50 percent in the forest canopy, and 48 percent in the forest floor. In the pine forest, 75 percent of the acid deposition was neutralized, all in the forest floor. The pine-hardwood ecosystem accumulated sulfate, nitrate, and ammonia ions, and lost base cations. During seasons of deficient precipitation, dry deposition appeared to enrich the concentrations of hydrogen, nitrate, sulfate, and ammonia ions in throughfall samples at both locations.     

"The little squealer" or "the virtual guardian angel"? Young drivers' and their parents' perspective on using a driver monitoring technology and its implications for parent-young driver communication

Introduction

In-vehicle driving monitoring technologies have the potential to enable young drivers to learn from self-assessment. However, their use is largely dependent on parental involvement.

Method

A total of 79 interviews were conducted with young drivers and parents regarding this technology and its use. Most had the experience of having an in-vehicle data recorder installed in the vehicle driven by the young drivers. Parents and the young drivers expressed both appreciation as well as reservations about its potential as a means to enhance the driving safety of young drivers.

Results

A surprising finding was that some parents did not check the feedback and said they relied on the young driver to do so. Main concerns related to privacy, parent-young driver relationship, self-esteem and confidence, constructive use of the feedback data, and the limitations of the documentation that can be done by the technology.

Conclusions

Providing parents and young drivers with a support system and tools to discuss and utilize the feedback are underscored. Challenges include addressing the invasion of young drivers’ privacy and gender differences, and using the monitoring-capacity of the technology to enhance safe driving practices. Implications for programs to enhance communication and a dialogical approach between parents and young drivers are discussed.     

Veränderungen der Eikapselvolumina während der entwicklung verschiedener Opisthobranchier-Arten (Mollusca,Gastropoda)

An attempt has been made to estimate volumes of eggs and egg-capsules employing the formula of the rotationellipsoid. Measurements of the following stages have been made: immediately after oviposition; blastula; gastrula; appearance of velumanlage; velarcilia, foot and velum small; velarcilia, foot and velum distinct; 1 to 2 days before hatching; hatching. Calculations permitt analysis of: (1) relationship between egg-case volume and egg-volume; (2) capsule volumes during development until hatching in comparison to those after oviposition (enlargement factor). The sacoglossan nudibranch Elysia viridis shows no increase in capsule volume during development. The nudibranchs Catriona aurantia, Tergipes despectus, Eubranchus exiguus, Eubranchus cingulatus, Eubranchus pallidus, Eubranchus farrani and Janolus cristatus reveal a distinct increase in capsule volume when velarcilia, foot, and velum appear. The degree of eggcapsule enlargement and its intensity during development exhibit interspecific differences. The results of this and of a previous paper (Kress, 1971) are compared and discussed with respect to possible explanations for the enlargements, (e.g. excretion of larval kidneys, composition of capsular fluid, influence of salinity).