The preparation and characterization of crystals of the superconducting polymer, (SN)x

A technique is described for growing (SN)_x crystals which have superior electrical properties to those reported previously. The room temperature electrical conductivity has increased, so has the ratio of the room temperature and 4°K resistivities. There is no conductivity maximum in the region 20–30°K and the superconducting transition temperature is higher.     

Critical Role of Estrogens on Bone Homeostasis in Both Male and Female: From Physiology to Medical Implications

Bone is a multi-skilled tissue, protecting major organs, regulating calcium phosphate balance and producing hormones. Its development during childhood determines height and stature as well as resistance against fracture in advanced age. Estrogens are key regulators of bone turnover in both females and males. These hormones play a major role in longitudinal and width growth throughout puberty as well as in the regulation of bone turnover. In women, estrogen deficiency is one of the major causes of postmenopausal osteoporosis. In this review, we will summarize the main clinical and experimental studies reporting the effects of estrogens not only in females but also in males, during different life stages. Effects of estrogens on bone involve either Estrogen Receptor (ER)α or ERβ depending on the type of bone (femur, vertebrae, tibia, mandible), the compartment (trabecular or cortical), cell types involved (osteoclasts, osteoblasts and osteocytes) and sex. Finally, we will discuss new ongoing strategies to increase the benefit/risk ratio of the hormonal treatment of menopause.     

The evaluation of the state of dispersion in immiscible blends where the minor phase exhibits fractionated crystallization

Summary Differential Scanning Calorimetry (DSC) can provide a qualitative measure of the state of dispersion of an immiscible blend if the minor phase exhibits fractionated crystallization when dispersed into fine particles. The technique is only sensitive to the volume of the dispersed particle and not to its shape and can only be used when the exotherms of interest do not overlap with other thermal transitions present in the multicomponent system. Selfnucleation is a valuable tool to ascertain the presence of fractionated crystallization. The morphology induced by fractionated crystallization in immiscible blends could lead to enhanced plastic deformation during yielding of the matrix.     

Treatment of Cs liquid wastes by reverse osmosis Part I. Preliminary tests

As a consequence of an accidental fusion of a ¹³⁷Cs source in a steel production factory, 40 m³ of radioactive liquids were generated in the plant decontamination process. This radioactive liquid waste was treated by a reverse osmosis plant, managing to declassify more than 36 m³. The remaining 4 m³ were treated by evaporation reducing the final volume to less than 1 m³. Prior to the waste treatment at the steel factory, preliminary tests were done in order to determine reverse osmosis membrane performance with ¹³⁷Cs effluents. The influence ofgamma and electron irradiation on structure and transport properties of reverse osmosis membranes was studied; and reverse osmosis performance with a ¹³⁷Cs-contaminated liquid obtained from contaminated ashes was assessed. The aim of this paper is to describe and show the results of these preliminary tests.     

Interactions between cleaning gobies and territorial damselfish on coral reefs

We studied the interactions between cleaning gobies, Elacatinus spp., at cleaning stations and territorial dusky damselfish, Stegastes fuscus, on a Barbadian fringing reef to enhance our understanding of the behavioural impact of cleaning stations on members of a coral reef community. Cleaning stations within damselfish territories were visited by significantly fewer species and fewer individuals than those outside damselfish territories. At cleaning stations within damselfish territories, the main client was the territory holder itself. Client behaviour did not differ between the two types of cleaning station; however, cleaning gobies at stations within damselfish territories spent less time cleaning clients, their cleaning bouts were shorter, and their feeding rate on clients was slower. These effects appear to be due to the repeated aggression of territorial damselfish towards fish intruding on to their territories to visit cleaning stations. The overlap between a territorial damselfish and a cleaning station therefore appears to have detrimental impacts on cleaning goby foraging. The presence of cleaning stations within damselfish territories exerted some effects on the territory owners. Although the rates of intrusions were similar on territories with and without cleaning stations, damselfish with cleaning stations tended to chase intruders more often, had a lower foraging rate, and were at higher risk of egg predation because of increased intrusions by egg predators. A potential benefit to territorial damselfish is regular access to a cleaning station; however, the magnitude of this benefit is unknown. This study reveals that damselfish, which are ubiquitous on coral reefs, can generate significant variation in levels of use of cleaning stations, which leads to new questions relating to the settlement behaviour of both cleaning gobies and damselfish. Copyright 1998 The Association for the Study of Animal Behaviour. Copyright 1998 The Association for the Study of Animal Behaviour.     

Treatment of Cs liquid wastes by reverse osmosis Part II. Real application

As a consequence of an accidental fusion of a ¹³⁷Cs source in a steel production factory, 40 m³ of radioactive liquids were generated in the plant decontamination process. This radioactive liquid waste was treated by a reverse osmosis plant, managing to declassify more than 36 m³. The remaining 4 m³ were treated by evaporation reducing the final volume to less than 1 m³. This paper describes the reverse osmosis plant used and the process of treatment, and presents the results of reverse osmosis membrane performance in the course of the treatment.