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Towards participatory environmental management?

While the mainstream approach to environmental management (EM) has tended to be centralized, adopting a narrow conception of 'environment', there is a growing body of literature supporting a participatory approach which is decentralized, community oriented and holistic in its view of the environment. This paper examines the main principles underlying this development and assesses the opportunities and constraints associated with it. It concludes that, while participation is conducive to a localized and inclusive approach to EM, many questions remain about the extent to which it is meaningful in practice or can be institutionalized.

Community-Institutional Relations↗

Emergent properties of food distribution among fire ant larvae

The flow of food into a fire ant colony is a decentralized process in which a global pattern, the even distribution of food among larvae, emerges from the interactions of individuals responding to each other with relatively simple rules of thumb. A simulation of worker-larva feeding interactions (rate and duration of worker-to-larva regurgitation) was employed to resolve the effect of each behavioral component on the distribution of food among larvae during one meal. When feeding interactions between workers and larvae simulated those of the fire ant (larvae signal for feedings at rates depending upon their size and their level of hunger; workers regurgitate a small, fixed volume of food), meal size was proportional to larval size, all larvae were brought to fullness together over an eight-hour period and the proportion of protein in each larva's meal was proportional to that found in the environment. These patterns of food distribution among larvae were the standard against which we compared simulated interactions. When simulated larvae signaled for feedings based upon their hunger (percent of midgut emptiness) but not their size, workers required nearly 12 hours to fill the last larva and, some larvae became full far sooner than others. When simulated larvae signaled for feedings based upon their size but not their hunger, they were brought to fullness evenly over time but were grossly overfed, absorbing food that would have been stored in worker crops. Lengthening the duration of worker-to-larva regurgitation generated substantial variation in the proportion of protein in larval meals, especially among small larvae. When simulated interactions were randomized, larvae received meals that varied substantially in volume and protein, some larvae were filled far sooner than others, and workers required over 24 hours and twice as much food to bring the last larva to fullness. Variation in worker response thresholds (simulated as variable worker-larvae ratios) affected only the total time required to deliver meals to larvae, Dissecting the relationship between worker-larva feeding interactions and the distribution of protein among larvae allowed us to propose a mechanism by which colony growth and reproduction could be regulated. Copyright 1998 Academic Press

Journal Article↗

EMEA and the new pharmaceutical procedures for Europe. European Medicines Evaluation Agency.

The regulation of medicines throughout Europe has undergone significant change since the first pharmaceutical Directive in 1965. 1995 will bring the next major stage in this evolution with the introduction of the so-called "Future System proposals". These will see the creation of the EMEA (the European Medicines Evaluation Agency), the introduction of a Centralized Procedure, applicable to a small number of innovative drugs, and a Decentralized Procedure, based on mutual recognition of licences granted by existing control authorities in other EC countries. The regulation of medicines in the United Kingdom has also changed considerably since the establishment of the Medicines Control Agency in 1989. This article looks at the new licensing arrangements for Europe and the development of medicines control in the UK over the last few years.

Drug and Narcotic Control↗

The study of locomotion by finite state models.

A methodology to derive finite state models of legged locomotion is outlined. Background data for model derivation are joint angle functions and gait diagrams. The method is used to describe the walking of the cat in terms of an abstract automaton. The main features of finite state descriptions of legged locomotion are described. Such models are presenting locomotion invariants of a species in explicit form. It is emphasized that finite state models provide insight into structural features of motor control organization such as decomposition into subsystems, interaction between centralized and decentralized control, and the role of control levels. The finite state model of locomotion can be helpful in suggesting experiments pertinent to the study of motor control and interpretation of experimental results.

Animals↗

Instrument myopia conceptions, misconceptions, and influencing factors.

The literature on instrument myopia is reviewed, with the review organized around three principal objectives. One is to describe and discuss various factors that may influence the degree to which instrument myopia is manifested, including monocular vs. binocular viewing, age, direction of focus, illumination level, fatigue, magnification, astigmatic variations, optical decentration, perceived proximity of the target and peripheral surround, and experience. The second objective is to discuss the intermediate resting state conception of accommodation, its application to instrument myopia, and its strengths and weaknesses as applied to the available literature. The third objective is to summarize the salient problems in the instrument myopia literature, and to present a set of recommendations for guiding future work.

Accommodation, Ocular↗

The ultrastructure of paraganglia associated with the inferior mesenteric ganglia in the guinea-pig.

The paraganglia of the inferior mesenteric ganglia in the guinea-pig are composed of small chromaffin cells containing an abundance of granule-containing vesicles. The chromaffin cells are almost completely surrounded by satellite cells. In areas in which satellite cell processes do not intervene, the membranes of adjacent chromaffin cells are closely apposed and often form specialized attachment zones. The paraganglia contain a dense capillary network, the endothelial cells of which are often extremely attenuated and show areas of fenestration. The processes of chromaffin cells approach close to the capillary walls and are often bare of satellite cells covering on the side facing the capillary. Evidence has been obtained for the exocytotic release of the contents of chromaffin cell vesicles into pericapillary spaces. Synapses of cholinergic and noradrenergic axons are seen on the chromaffin cells. The cholinergic axons degenerate when the praganglia are decentralized, but the noradrenergic axons, which appear to arise from the local inferior mesenteric ganglia, remain intact. The results suggest that the paraganglia have an endocrine function.

Animals↗

The localization of the beta-subtype of protein kinase C (PKC-beta) in rat sympathetic neurons.

The localization of PKC-beta was studied in rat sympathetic neurons using a polyclonal antibody specific for the beta 1- and beta 2-subspecies. The tissues studied included the superior cervical (SCG) and hypogastric (HGG) ganglia and the target tissues of the SCG and HGG neurons: the submandibular gland, iris, prostate and vas deferens. PKC-beta-LI was found in nerve fibers in both ganglia. A proportion of the fibers in the SCG disappeared after decentralization, suggesting that the fibers were of both pre- and postganglionic origin. The somata of the HGG and SCG neurons expressed varying amounts of PKC-beta-LI, the majority of SCG neurons being labelled only after colchicine treatment. In all target tissues there were PKC-beta-immunoreactive nerve fibers in bundles, but the most peripheral branches of the fibers were negatively labelled. The results show that PKC-beta-LI is widely present in sympathetic postganglionic neurons with mainly quantitative differences. The lack of PKC-beta in the most peripheral branches of nerve fibers might be a general feature of sympathetic postganglionic neurons, suggesting that the participation of PKC-beta in neurotransmitter release and in other functions in nerve terminals in sympathetic adrenergic neurons is unlikely.

Animals↗

The evolving horizon of drug registration--Europe and beyond.

The thalidomide tragedy gave rise to national drug regulation without thought to international harmonization. Thus from the early days of the European Community (EC), there has been a barrier to the free movement of medicinal products. Previous attempts have failed to resolve the problem and the European Commission is currently involved in attempting to establish Community drug legislation which will remove these barriers and create a single internal market. The Commission advocates two procedures (a centralized and a decentralized) largely under the control of the Committee for Proprietary Medicinal Products (CPMP) within the framework of a new European Agency for the Evaluation of Medicinal Products. The present authority of the Commission to make decisions binding on all 12 Member States will be utilized by the CPMP. While the present draft legislation should create significant improvement towards the goal of a single market, it contains some areas of potential concern. That this major venture should be a success is not only critical to the EC economy, its research-based pharmaceutical industry and the health care of its citizens but also to the achievement of global harmonization for pharmaceutical marketing authorization for which there is much evidence of enthusiasm and desire.

European Union↗

Population and structure of nerve cells in mouse submandibular ganglion.

The anatomy of the mouse submandibular ganglion, and population and fine structure of nerve cells were studied by light and electron microscopy. The submandibular ganglion is a plexus containing up to forty ganglia along the main and the smaller excretory ducts of the submandibular gland. Measurements of the volume of nerve cell bodies display a pattern of distribution with two main peaks, suggesting the presence of large and small types of the intraganglionic neuron. The large neurons mainly have axo-dendritic synapses in which the postsynaptic element is a small spine-like process, while axo-somatic synapses are more common in the small neurons. In some small neurons nuclear chromatin is unusually conspicuous, and accumulations of vesicles of fairly uniform size occur within the cell body. Decentralized ganglia contain almost no synapses showing the absence of definite interneurons.

Animals↗

Biotechnology in Japan 1984--a mini-review. Part 2: Government agencies, universities and research institutes.

Major developments in Japanese biotechnology in 1984 are reviewed. Besides industry and academia, research associations (companies and governmental research institutions guided by ministries) carry out joint fundamental research in biotechnology. Another important long-range aspect is the Technopolis Concept, which aims at decentralizing research and technological activities.

Agriculture↗

Diurnal rhythm of mitosis in rabbit corneal epithelium.

Incorporation of 3H-thymidine by rabbit corneal epithelium during the course of a one-hour incubation in vitro varies according to the time of day, suggesting a diurnal rhythm of mitotic activity. Adrenergic decentralization of the cornea does not affect this rhythm. Furthermore, there is no diurnal variation in the basal or sympathomimetically-stimulated cyclic AMP production by freshly excised rabbit corneas, incubated in vitro. Therefore, the diurnal rhythm of corneal epithelial mitotsis in the rabbit is not paced by catecholamines.

Animals↗

Integrating health-related quality of life into cross-national clinical trials.

When planning to implement health-related quality of life (HRQL) assessment in a multinational clinical trial, there are at least four general considerations: the natural history of the disease or condition, the characteristics of the population, the treatment under consideration, and the structure and function of the clinical trial organization. Each of these considerations must be addressed simultaneously when planning, implementing and analysing a cross-national clinical trial. There are five relevant polar components of the natural history of a given disease or condition: (1) time frame (acute versus chronic); (2) life threat (yes versus no); (3) symptomatology (present versus absent); (4) symptom expression (episodic versus constant); and (5) functional impact (present versus absent). Differences in population characteristics, (e.g., age, conditions, co-morbidity), embedded within any cross-national trial, must be addressed conceptually prior to initiating the trial, methodologically when planning implementation, and statistically after the collection of the data. In terms of treatment, issues such as adverse and positive effects and timing of effects must be considered. The methods entailed in planning, implementing and analysing HRQL data will depend upon the degree of centralization of personnel and resources within any given clinical trial. The range of possibilities runs from complete centralization, in which all planning and coordination of data collection and transmittal is done by one office, to complete decentralization, in which the work is distributed to participating sites and interested investigators. Finally, successful implementation of HRQL data collection is enhanced by heightening awareness of the importance of, and value in, assessing HRQL in clinical trials.(ABSTRACT TRUNCATED AT 250 WORDS)

Cross-Cultural Comparison↗

Norepinephrine release from nerve terminals within the rabbit superior cervical ganglion.

Norepinephrine-3H (NE-3H) and its metabolic normetanephrine-3H were released from the superfused rabbit SCG incubated in tyrosine-3H in response to preganglionic stimulation. Neither dopamine-3H nor its metabolite, 3-methoxy-tyrosine could be detected in the superfusate from "control" or "nerve stimulated" tissues. Nerve stimulated NE-3H release a) was calcium dependent, b) had a stimulus threshold similar to that of C fibers, c) was not blocked by either 50 micromolar curare or 100 micromolar atropine, d) was abolished by chronic decentralization and e) was elicited by stimulation of both the cervical sympathetic and internal carotid nerves. These results suggest that there is a here-to-for undescribed, noradrenergic pathway which originates elsewhere in the sympathetic chain but terminates in the superior cervical ganglion.

Animals↗

B-HT 958, a new alpha-adrenoceptor agonist with a high pre/postsynaptic activity ratio.

B-HT 958 (2-amino-6-(p-chlorobenzyl)-4H-5,6,7,8-tetrahydrothiazolo [5,4-d] azepine) was a potent agonist at presynaptic and a less potent agonist at postsynaptic alpha-adrenoceptor sites. Presynaptically this was shown in pithed rats by the inhibition of tachycardia evoked by sympathetic nerve stimulation (0.2 Hz). The 50% inhibitory dose (ID50) was 0.3 mg/kg i.v. Moreover in isolated perfused cat hearts, the drug inhibited the tachycardia and the outflow of noradrenaline induced by sympathetic nerve impulses. These effects of B-HT 958 were antagonized by phentolamine or yohimbine. At postsynaptic sites high doses of B-HT 958 increased the blood pressure of decentralized rats. The dose which increased pressure by 30 mm Hg (PD 30) was 46.3 mg/kg i.v. This effect was antagonized by rauwolscine 5 mg/kg i.v. After pretreatment with reserpine (7.5 mg/kg i.p., 18 h) B-HT 958 proved much more potent (PD 30 = 0.6 mg/kg i.v.) and its effect was strongly antagonized by yohimbine but hardly by prazosin. The dose of yohimbine which shifted the dose-response curve of B-HT 958 by the factor of 10 (D10) to the right was 1.8 mg/kg iv., the corresponding dose of prazosin was 1,900 mg/kg i.v. (extrapolated). B-HT 958 showed also alpha-adrenoceptor blocking properties. This was demonstrated presynaptically in pithed rats by the drug-induced augmentation of tachycardia elicited by electrical stimulation at high frequency (6.4 Hz). At postsynaptic sites B-HT 958 antagonized the blood pressure increase-caused by B-HT 920 (alpha 2; D10 = 1.1 mg/kg i.v.) but not that caused by methoxamine (alpha1). It is concluded that B-HT 958 is a partial agonist at peripheral alpha 2-adrenoceptors. In doses of about 1 mg/kg and with low frequency sympathetic stimulation (less than 6.4 Hz) it acts presynaptically as agonist; in this dose the drug acts postsynaptically mainly as antagonist.

Adrenergic alpha-Agonists↗

Nonequilibrium ion transport through pores. The influence of barrier structures on current fluctuations, transient phenomena and admittance.

In this paper is presented an investigation of the influence of the internal structure of pores in membranes on a) the time dependent macroscopic relaxation current after a voltage jump, b) the macroscopic frequency dependent admittance and c) the microscopic current fluctuations around stationary (nonequilibrium) states. All these quantities are determined by the time dependent transport equations, which are calculated with the use of the eigenvectors and eigenvalues of the matrix of coefficients, occurring in the transport equations. Numerical calculations for channels with up to 31 barriers are presented. The treatment of the fluctuations is done with the use of a general approach to nonequilibrium transport noise recently developed by one of the authors. It is shown that the influence of the internal barrier structure as, e.g., the height of central or decentral barriers in the pores is of great complexity. Nevertheless we hope that the calculations lead to a better understanding especially of the microscopic nonequilibrium transport fluctuations in complex systems.

Ion Channels↗

Stimulation of the synthesis of catecholamines in a sympathetic ganglion via cholinergic and non-cholinergic mechanisms.

Electrical stimulation of the preganglionic sympathetic neurons rapidly and markedly elevated the contents of the primary dopamine (DA) and noradrenaline (NA) metabolites, i.e., 3,4-dihydroxyphenylacetic acid (DOPAC) and 3,4-dihydroxyphenylethylene glycol (DOPEG) in the superior cervical ganglion and it enhanced the accumulation of DOPAC and DA following inhibition of the DA-beta-hydroxylase by FLA-63. The stimulation also increased the concentration of DA and decreased the concentration of NA in the salivary gland both without and with DA-beta-hydroxylase inhibition. Chlorisondamine inhibited the increase in ganglionic DOPAC following preganglionic stimulation (5 Hz, 30 min) by 30-50% and it even better reduced the biochemical changes in the salivary gland. Atropine did not produce any clearcut inhibition of the stimulation-induced effects on the superior cervical ganglion or the salivary gland, nor did it enhance the effect of chlorisondamine. The results suggest that nicotine, but not muscarine receptors in the cell body region of the postganglionic NA neurons partially mediate the effects of preganglionic stimulation. The effects remaining after blockade of the nicotine and muscarine receptors might be due to release of a neuropeptide acting on a special receptor. The stimulation-induced increase in the concentration of DOPAC in the superior cervical ganglion might, at least partly, be the result of a depolarization of the NA nerve cell body regions since similar changes were produced by electrical stimulation of the chronically decentralized ganglion.

3,4-Dihydroxyphenylacetic Acid↗

Mental health consumer survey on a shoestring budget-it is possible!

Consumers of service in a decentralized unit of a county mental health services organization were surveyed. Two samples, one of 100 and one of 386 former clients, were selected for a questionnaire survey of satisfaction and perception of ensuing changes. This report is offered as an example of what a busy clinical team can accomplish in the midst of its basic task of providing therapeutic and diagnostic help.

Community Mental Health Services↗

Clinical results with three different kinds of small optic PMMA-IOLs.

In this prospective study the clinical results using three different small optic IOLs are presented. The best results were achieved in those cases with an anterior capsule rim overlapping the entire optic periphery. In those cases with sulcus fixation, haptic in/out and optic in/out positions a higher percentage of capsule fibrosis (Soemmering's rings) was documented (sulcus fixation: 100%, haptic in/out position: 75%, optic in/out position: 65.5%, bag: 7.3%). The fibrosis developed because of contact between the anterior and the posterior capsule leaf. These cases also showed decentrations of the intraocular lens (IOL) more often (sulcus fixation: 50%, haptic in/out position: 75%, optic in/out position: 34.5%, bag: 31.7%). Only one patient was disturbed by glare and halo phenomenons. Cellular reactions on the lens surface were moderate in most cases. Differences specific to lens type were found between the three IOLs implanted. The clinical results were comparable to the results of other comprehensive IOL studies. Under certain indication small optic IOLs represent an alternative to flexible implants for small incision surgery.

Aged↗