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The impact of agricultural land use on the composition and structure of aquatic insect assemblages (i.e., taxa of Ephemeroptera, Plecoptera, Trichoptera, and Coleoptera (EPTC)) was investigated in tributary streams of the Garonne river basin, southern France. The self-organizing map (SOM) method was applied to compare both instream environmental conditions and EPTC assemblages between forest and agricultural streams. According to the SOM model, the study sites were classified into three main clusters corresponding to distinct EPTC assemblages. The SOM cluster associated with most of the agricultural sites had lower EPTC species richness and diversity. This cluster was also characterized by high levels of total dissolved solids, nitrate (NO3), and chemical oxygen demand. Overall, our study shows that agricultural streams when compared with forest streams had lower biological integrity. In accordance with the European Water Framework Directive, our results indicate that the sites most impacted by agricultural land use should be restored and that the least-impacted forest sites could serve as reference conditions.

The dynamics of benthic detritus and the structure, composition and functional feeding groups of as- sociated macroinvertebrate communities were followed at biweekly intervals over one year in a 4th-order Andean stream located in a forested hill in SW Colombia. The density of macroinvertebrates and the number of taxa showed a similar bimodal annual pattern with highest values occurring from January to mid-March and from July to mid- October. The accumulated benthic detritus and the invertebrate abundance and community structure were appar- ently controlled by stream discharge. This was confirmed by a cluster analysis of invertebrate assemblages over the year where three groups of sampling dates emerged. The first group occurred during high discharges, the second one under intermediate hydrological conditions and the third coincided with low rainfall and low discharges. Nu- merically, collectors dominated, whereas shredders represented less than 5.3 % of the invertebrates. Unexpectedly, benthic detritus and collector densities were negatively correlated; however, no relation between benthic detritus and the abundance of shredders was found, which may suggest that benthic detritus consisting mainly of plant remains was not a limiting resource in this neotropical stream. Macroinvertebrates appear to have a minor role in the decomposition of plant matter which is consistent with previous observations from the same and other tropical streams. As a consequence, macroinvertebrate dynamics in this stream were more influenced by hydrological vari- ations than by input of plant detritus.

L'abondance, la richesse specifique et la structure des communautes de trois groupes de macroinvertebres (Plecopteres, Ephemeropteres et Dipteres Simuliidae) ont ete etudiees dans le bassin de l'oued Sebaou (Algerie). Cinquante-cinq taxa ont ete identifies (22 Ephemeropteres, 14 Plecopteres et 19 Simulies) dans 18 stations situees sur le cours principal et les affluents de l'Oued Sebaou (Grande Kabylie, Algerie). La diversite specifique des differentes stations revele un gradient altitudinal avec une diversite maximale dans les zones de piemont et de basse montagne (200 a 500 m) qui constituent les zones les plus heterogenes. Au contraire, la faible diversite des zones de plaine peut etre attribuee a une temperature de l'eau elevee, a un faible debit ainsi qu'a l'influence des perturbations anthropiques. De meme, la faible diversite des zones d'altitude semble due soit aux faibles temperatures, soit a la forte amplitude thermique journaliere. L'etude des associations d'especes revele trois groupes, les deux premiers etant essentiellement determines par un gradient altitudinal. Les zones amont sont caracterisees par des especes de Plecopteres alors que les zones de piemont presentent une forte abondance et une forte diversite d'Ephemeropteres et de Simuliidae. Le troisieme groupe est caracteristique des sources, avec des especes de Plecopteres peu frequentes et peu abondantes. Aussi bien le gradient altitudinal de diversite que les associations d'especes dans le bassin de l'oued Sebaou, s'averent differents de ceux rencontres en Europe temperee. Cette etude revele que le climat mediterraneen accentue d'Afrique du Nord induit des differences de composition specifique, mais egalement de structure des communautes. Ces resultats fournissent des informations quant a l'influence de variables environnementales sur la distribution des especes et la structure des communautes d'insectes aquatiques en Afrique du nord.

Synecological analyses are usually based on typological, phenetic and cladistic methods. The disadvantages of these techniques are shown. The application of the Wagner parsimony method to synecology is considered. All the methods need some prerequisites, viz. definitions of localities and characters (the most simple one being the presence/absence of taxa); the choice of taxonomic level of taxa; their autochthony. The application of Wagner parsimony needs a new terminology. The congruence of any environmental condition, including freshwater monitoring indices, can be tested on parsimonious trees. The Wagner parsimony method not only provides various indices (tree length, CI, HI, RC, RI) which allow the comparison of trees but also minimal trees which are direct tools in synecology

Besides stimulating GH release, some GH secretagogues also release ACTH and adrenal steroids. Several novel classes of potent GH secretagogues have recently been described, and we have now tested their ability to release corticosterone in conscious normal rats. All analogs that released GH also stimulated corticosterone release to some degree, though the relative effects on GH and corticosterone varied somewhat. The corticosterone responses for some analogs were in the range of those obtained with CRF (2 μg, iv), whereas closely related analogs inactive for GH release failed to release corticosterone. Activation of the hypothalamic-pituitary-adrenal axis with GH release by GHRPs could be a highly diabetogenic combination in susceptible individuals. Therefore, a potent GHRP pentapeptide analog (G7039, 100μ g/day, sc, bid) was given to young obese male Zucker diabetic fatty rats (ZDF, n = 8/group) for 24 days. Other groups received hGH (500 μg/day, sc, bid), recombinant human insulin-like growth factor (rhI...

Expression of human growth hormone (hGH) was targeted to growth hormone-releasing (GRF) neurons in the hypothalamus of transgenic rats. This induced dominant dwarfism by local feedback inhibition of GRF. One line, bearing a single copy of a GRF-hGH transgene, has been characterized in detail, and has been termed Tgr (for Transgenic growth-retarded). hGH was detected by immunocytochemistry in the brain, restricted to the median eminence of the hypothalamus. Low levels were also detected in the anterior pituitary gland by radioimmunoassay. Transgene expression in these sites was confirmed by RT-PCR. Tgr rats had reduced hypothalamic GRF and mRNA, in contrast to the increased GRF expression which accompanies GH deficiency in other dwarf rats. Endogenous GH mRNA, GH content, pituitary size and somatotroph cell number were also reduced significantly in Tgr rats. Pituitary adrenocorticotrophic hormone (ACTH) and thyroid-stimulating hormone (TSH) levels were normal, but prolactin content, mRNA levels and lactotroph cell numbers were also slightly reduced, probably due to feedback inhibition of prolactin by the lactogenic properties of the hGH transgene. This is the first dominant dwarf rat strain to be reported and will provide a valuable model for evaluating the effects of transgene expression on endogenous GH secretion, as well as the use of GH secretagogues for the treatment of dwarfism.

The effects of growth hormone-releasing peptide-6 (GHRP-6) on peripheral plasma concentrations of growth hormone (GH) and hypophysial portal plasma concentrations of growth hormone-releasing hormone (GHRH) and somatostatin (SRIF) were investigated in conscious ewes. Paired blood samples were collected from the hypophysial portal vessels and from the jugular vein of nine ewes for at least 2 hr. The sheep were then given a bolus injection of 10 micrograms of GHRP-6 per kg followed by a 2-hr infusion of GHRP-6 (0.1 microgram/kg.hr). Blood sampling continued throughout the infusion and for 2 hr afterwards. An increase in plasma GH concentration was observed in the jugular samples of six of the nine ewes (1.4 +/- 0.3 vs 7.4 +/- 2.0 ng/ml, P0.05) 5-10 min after the GHRP-6 bolus injection, but in no case did we observe a significant coincident release of GHRH. During the infusion period, mean plasma GHRH levels were not significantly increased but there was a 50% increase (P0.05) in GHRH pulse frequency; GHRH pulse amplitude was not changed. Mean SRIF concentration, pulse frequency, and pulse amplitude were unchanged by GHRP-6 treatment. These data indicate that GHRP-6 causes a small, but significant effect on the pulsatile secretion of GHRH, indicating action at the hypothalamus or higher centers of the brain. The large initial GH secretory response to GHRP-6 injection does not appear to be the result of GHRP-6 action on GHRH or SRIF secretion.

Southwestern France consists of 24 departments and covers an area of 128,000 km2. A list of 60 unquestionably valid spe­ cies of mayflies is provided for the region. The study area is the Terra typica of ten of the species : one described by Joly, two by Eaton, and seven by Thomas et al. Five species are endemic to the Pyrenees and are probably restricted to the north slope : Baetis catharus, B. nicolae, Rhithrogena kimminsi, R. strenua, and Habroleptoides berthelemyi. R. germanica, Ecdyonurus macani, and Ephemera vulgata are at risk because their hyporhithron and epipotamon habitats have been endangered by agri­ culture runoff, regulation, and diversion of the streams for irrigation, in particular when the water levels are already very low. For the same reasons, Isonychia ignota, Neoephemera maxima, Brachycercus harisella, and Ephemera glaucops have not been taken for over a century, and Prosopistoma foliaceum for more than 60 years, and all have presumably vanished from the re­ gion.

Le regime alimentaire des larves de Chaoborus flavicans a ete etudie dans le troisieme bassin (profondeur = 0,8 m) de la lagune d'epuration des eaux usees d'un village de l'Aveyron. Sur un cycle annuel, l'eau a ete constamment saturee en oxygene a la surface ; sur le fond, le pourcentage de saturation a varie entre 62,8 et 141,4%. La temperature de l'eau a varie de 4,6 a 25,7%C. La concentration moyenne annuelle en chlorophylle a a ete de 99,3 μg/l, et la biomasse annuelle moyenne de zooplancton de 4,4 g/m 2 en poids sec, incluant en particulier Brachionus calyciflorus et Polyarthra remata (Rotiferes), et Daphnia pulex (Cladoceres). La population de C. flavicans realise cinq generations par an et sa densite a varie entre 1931 et 21586 individus/m 2 . Le pourcentage d'estomacs vides n'est pas significativement different pour les quatre stades larvaires. La caracterisation du regime alimentaire des larves a fait appel aux indices : de Frequence, de Contribution Numerique, de Contribution Ponderale, et tout particulierement d'Importance Relative - deja utilise en ichthyologie (Pinkas et al, 1971). Aux trois premiers stades, les larves se nourrissent exclusivement de B. calyciflorus. Au contraire, les larves de stade IV presentent une grande euryphagie, pas significativement differente sur le fond et en pleine eau. L'Indice d'Importance Relative et l'Indice de Selectivite (Vanderploeg & Scavia 1979) indiquent que ces dernieres exploitent les ressources trophiques de la lagune selon un gradient de vulnerabilite decroissante des proies.

It takes a few millimetres of rainfall to cause the 34 most polluting combined sewer overflows (CSOs) to discharge into the River Thames. Currently, in a typical year, spillages to the tidal reaches of the River Thames occur about 60 times, with an estimated spill volume of 39 million cubic metres. Both the UK Government and the European Union have determined that the CSO discharges have an adverse environmental impact on fish species, introduce unacceptable aesthetics and elevate the health risks for recreational users of the Thames, with a frequency of discharge which is in breach of the Urban Wastewater Treatment Directive. Studies have established that the environmental objectives can be fully met on the most cost-effective basis by completing both quality improvements to treatment works and by the provision of a storage and transfer tunnel to intercept unsatisfactory CSOs. Extensive modelling has been undertaken to develop an optimised solution. In parallel with the design development a rigorous and comprehensive site selection methodology has been established to select sites and consult stakeholders and the public on the preferred sites and scheme, with the first stage of public consultation planned for later in 2010. The London Tideway Tunnels are an essential part of the delivery of improvements to the water quality of the tidal River Thames, and this ambitious, historic scheme represents a vital strategic investment in London’s infrastructure.

Mayflies (Ephemeroptera) are known to have short adult life-spans. Adults are unable to feed, and they utilize reserves stored during their aquatic larval stage. Energy reserves (fat, glycogen, and free sugars) of mature larvae, subimagoes and imagoes of both sexes of Siphlonurus aestivalis Eaton were compared. All the stages of both sexes had low glycogen and free sugar contents, and the only significant change occurred during the transformation of the mature larva to subimago when almost all the reserves of free sugars were used up. Glycogen and free sugars may serve as energy sources permitting individuals to swim and fly out of the water during emergence. Fat made up most of the energy reserves of mature larvae and was the main source of energy used during the final development of both sexes. Young adult males had high fat reserves which they used as a source of energy for their swarming flights. In contrast, females did not seem to use a significant amount of fat for flight. This difference is probably related to the different mating strategies of the sexes in this species. Males perform long flights waiting for females, whereas females perform only brief flights to mate and reproduce.

These studies characterized the secretion of GH-releasing factor (GRF) and somatostatin (SRIF) into the hypophysial portal circulation in ewes after long term restricted feeding. In addition, we examined the temporal relationship between the concentrations of these two hypothalamic peptides in portal blood and the concentration of GH in jugular blood. Six sheep were fed 1000 g hay/day (normal feeding) and 6 sheep were fed 400-600 g hay/day (restricted feeding). This resulted in a wt loss of 35% in restricted animals compared with 6% in control animals after 20 weeks. Fluctuations in portal levels of GRF indicated a pulsatile pattern of secretion with approximately 60% of pulses coincident with, or immediately preceding, a GH pulse. Similarly, 65% of GH pulses were associated with GRF pulses. Restricted feeding increased (P less than 0.01) mean ( +/- SEM) plasma GH levels (9.8 +/- 1.4 vs. 2.9 +/- 0.6 ng/ml) and mean GH pulse amplitude (7.9 +/- 1.8 vs. 2.8 +/- 0.3 ng/ml) but did not affect mean GH pulse frequency (6.0 +/- 1.1 vs. 5.7 +/- 1.1 pulses/8 h). The level of feeding had no effect on mean portal concentration of GRF (restricted: 5.5 +/- 0.8, normal: 6.6 +/- 1.4 pg/ml), GRF pulse amplitude (14.7 +/- 2.3 vs. 13.5 +/- 0.7 pg/ml), or GRF pulse frequency (5.3 +/- 1.1 vs. 6.7 +/- 0.9 pulses/8 h). Portal concentrations of SRIF in sheep on a restricted diet were half (P less than 0.01) those of sheep fed a normal diet (10.2 +/- 2.3 vs. 19.6 +/- 1.6 pg/ml). Pulses of SRIF were not significantly associated with changes in GH or GRF concentrations. These data indicate a functional role for hypothalamic GRF in initiating GH pulses. Furthermore, the increase in GH secretion in underfed sheep was most probably due to a decrease in the release of SRIF into hypophysial portal blood. Restricted feeding had no affect on GRF secretion, but because of the reduced exposure of the pituitary gland to SRIF, it is possible that responsiveness to GRF is enhanced.

To elucidate the role of growth hormone (GH)-releasing hormone (GRH) and somatostatin (SRIH) in the regulation of the growth hormone (GH) secretory pattern, we collected portal blood from five unanesthetized ovariectomized ewes for repeated measurements of GRH and SRIH simultaneous with those of peripheral GH. Hormones were measured at 10-min intervals for 5.5 h and their interrelationships analyzed. Mean portal GRH was 20.4 +/- 6.7 (SD) pg/ml and the estimated overall secretion rate was 13 pg/min. GRH secretion was pulsatile with peaks of 25-40 pg/ml and a mean pulse interval of 71 min. Mean portal SRIH was 72 +/- 33 pg/ml and the estimated overall secretion rate was 32 pg/min. SRIH secretion was also pulsatile with peaks of 65-160 pg/ml and a mean pulse interval of 54 min. The GH pulse interval was 62 min. A significant association was present between GRH and GH secretory peaks though not between GRH and SRIH or SRIH and GH. Insulin hypoglycemia resulted in a rapid and brief stimulation of SRIH secretion followed by a decline in GH levels. No effect was observed on GRH secretion until 90 min, when a slight increase occurred. The results suggest (a) the presence of an independent neural rhythmicity of GRH and SRIH secretion with a primary role of GRH in determining pulsatile GRH secretion, and (b) that the inhibitory effects of insulin hypoglycemia on GH in this species are attributable to a combination of enhanced SRIH secretion and possibly other factors, though without significant inhibition of GRH.

The effects of long term restricted feeding on the synthesis, storage, and release of GH, LH, FSH, and PRL were examined in adult ovariectomized ewes. Two groups of six ewes were fed a diet of either 1000 g/day (normal feeding) or 400-600 g/day (restricted feeding) hay for 20 weeks. Restricted feeding increased mean plasma GH concentrations and the amplitude of GH pulses, but did not affect GH pulse frequency. In contrast, mean plasma LH and FSH concentrations and LH pulse frequency were decreased by restricted feeding. Mean plasma PRL concentrations were unaffected by treatment. The levels of mRNA for GH in pituitary cytosol were increased by restricted feeding, but no changes were seen in mRNA levels of alpha-subunit, LH beta, FSH beta, or PRL. The pituitary contents of hormones measured did not change with the level of feeding. In conclusion, these data show that long term restricted feeding affects anterior pituitary function in adult ewes, presumably reflecting alterations in the secretion of hypothalamic releasing and inhibiting factors.

Signal transducers and activators of transcription (STATs) are a family of transcription factors linked to class I cytokine receptors. In the present study, we investigated whether their distribution in the hypothalamus reflects the feedback regulation by growth hormone and what role they might play in the functioning of target neurones. We demonstrate that each of the seven known STATs has a distinct distribution in the hypothalamus. Notably, the STAT5 proteins, that are important in growth hormone (GH) and prolactin signalling in peripheral tissues, were expressed in somatostatin neurones of the periventricular nucleus and dopamine neurones of the arcuate nucleus. Because somatostatin neurones are regulated by feedback from circulating GH, we investigated the importance of STAT5 in these neurones. We demonstrate that STAT5b protein expression, similar to somatostatin mRNA, is sexually dimorphic in the periventricular nucleus of rats and mice. Furthermore, chronic infusion of male dwarf rats with GH increased the expression of STAT5b, while a single injection of GH into similar rats induced the phosphorylation of STAT5 proteins. The cellular abundance of somatostatin mRNA in STAT5b-deficient mice was significantly reduced in the periventricular nucleus, effectively reducing the sexually dimorphic expression. These results are consistent with the hypothesis that STAT5 proteins are involved in the feedback regulation of somatostatin neurones by GH, and that these neurones may respond to patterned GH secretion to reinforce sexual dimorphism in the GH axis.

Synthetic GH-releasing peptides such as GHRP-6 are potent GH secretagogues (GHSs) in several species, but attempts to stimulate growth by continuous GHS exposure have had limited success. GHSs also release ACTH and adrenal steroids. Since glucocorticoid excess is associated with poor linear growth, stimulation of the hypothalamo-pituitary-adrenal (HPA) axis by continuous GHS administration may compromise their growth-promoting effects. We have now examined the effects of continuous GHRP-6 infusion (100 mg/day, s.c. for 14 days) in normal 150-day-old female rats, and in adrenalectomized (Adx) rats with or without dexamethasone (Dex) replacement. Infusion of GHRP-6 did not significantly affect body weight gain compared with excipient-treated controls in either intact rats (controls, 9.0 +/- 1.6 vs GHRP-6, 11.8 +/- 0.9 g) or Adx rats (4.4 +/- 1.5 vs 7.9 +/- 2.7 g). However, GHRP-6 significantly increased weight gain in Adx rats treated with Dex (controls, 3.5 +/- 1.4 vs GHRP-6, 15.4 +/- 1.6 g;P

Besides stimulating GH release, some GH secretagogues also release ACTH and adrenal steroids. Several novel classes of potent GH secretagogues have recently been described, and we have now tested their ability to release corticosterone in conscious normal rats. All analogs that released GH also stimulated corticosterone release to some degree, though the relative effects on GH and corticosterone varied somewhat. The corticosterone responses for some analogs were in the range of those obtained with CRF (2 microg, iv), whereas closely related analogs inactive for GH release failed to release corticosterone. Activation of the hypothalamic-pituitary-adrenal axis with GH release by GHRPs could be a highly diabetogenic combination in susceptible individuals. Therefore, a potent GHRP pentapeptide analog (G7039, 100 microg/day, sc, bid) was given to young obese male Zucker diabetic fatty rats (ZDF, n = 8/group) for 24 days. Other groups received hGH (500 microg/day, sc, bid), recombinant human insulin-like growth factor (rhIGF)-1 (750 microg/day, sc, infusion) or excipient, alone or in combination. Both G7039 and hGH increased weight gain, markedly raised serum glucose (G7039, 542 +/- 37; hGH, 725 +/- 30; excipient, 330 +/- 57 mg/dl) and doubled insulin levels but had opposite effects on serum triglycerides (G7039, 1412 +/- 44; hGH 501 +/- 46; excipient 1058 +/- 73 mg/dl) and fat depot weights. In contrast, treatment with IGF-1, alone or in combination with hGH or G7039, improved the diabetic state and stimulated growth. Thus, both G7039 and hGH treatment stimulated growth in ZDF rats, but greatly worsened diabetes, unless IGF-1 was coadministered. Some of the effects ofG7039 could be explained by GH release, but the effects on blood lipids and body fat were not seen with hGH and may reflect the additional activation of the hypothalamic-pituitary-adrenal axis by the secretagogue. The magnitude of these adverse effects in the ZDF animals suggest that chronic administration of GHRP analogs with cortisol-releasing activity to obese or diabetes-prone individuals warrants careful evaluation.

The last complete listing of mayflies of France was published in 1922. The current work updates the species of each province and Corsica as part of the National Inventory (INVFMR) recently initiated by the authors and coll. A total of 149 species in 37 genera are treated. Major synonyms are also noted. The status and/or distribution of twelve species remain questionable and require further investigation. Eighteen species known from areas peripheral to France are considered as potentially occuring in France., Le dernier catalogue exhaustif des Ephémères de France datant de 1922, une liste bibliographique actualisée des espèces signalées par départements (Corse incluse) est dressée, dans le cadre de l'Inventaire National (INVFMR) que les auteurs et coll. viennent de lancer. Les principales synonymies sont mentionnées. Pour douze espèces, statut et/ou provenance sont toutefois douteux et doivent être vérifiés. Dix-huit autres espèces, signalées seulement de régions frontalières, sont considérées comme potentielles pour la faune de France. La liste totale compte 149 espèces, regroupées en 37 genres., Thomas Alain, Masselot Gérard. Les Ephémères de France : inventaire des espèces signalées et des espèces potentielles (Ephemeroptera). In: Bulletin de la Société entomologique de France, volume 101 (5), décembre 1996. pp. 467-488.

Sound attenuation and speech intelligibility evaluations were conducted on a modified active noise reduction (ANR) headset being considered for use by sensor operators in Navy P3-C aircraft. Measurements were obtained on 10 male ensigns in the Naval Aviation Flight Training Program. A comparison of the sound attenuation values obtained with the ANR on (combined passive and active attenuation) to values obtained with the ANR off' (passive attenuation) revealed 10-15 (B greater attenuation at 125, 250 and 500 Hz, and 1-5 dB less attenuation at 1000 and 2000 Hz. Speech intelligibility scores obtained with the ANR on were 10% greater than scores obtained with the ANR off' at the two highest noise levels (110 and 115 dB SPL). The results of the evaluations demonstrated that ANR technology could prove beneficial to sensor operators in P3-C acoustical environments. Improved low-frequency noise attenuation should enhance sensor operator performance in monitoring low-frequency acoustical signals and decrease the likelihood that operators would sustain auditory fatigue during typical long-duration flights. The results were instrumental in the decision to proceed with the further development and procurement of the headset for use by sensor operators in the Navy's P3-C community. (MM)

The putative negative feedback effects of IGF-I and IGF-II on GH secretion were tested by intracerebroventricular (icv) and intrapituitary administration to sheep. Over two consecutive days, serial jugular blood samples were taken at 10 min intervals for 6 h from ewes (n=3/group) fitted with indwelling stainless steel cannulae into the lateral or third cerebral ventricles. The sheep were injected (icv) with either vehicle or purified ovine IGF-I (2, 4 or 8 μg). IGF-I injection had no effect on plasma GH secretion. Serial blood samples were taken from a second group of nine ewes in which ovine or recombinant human (rh) IGF-I was infused (2·5 μg/h for 2 h) into the third ventricle; once again, IGF-I failed to affect the episodic pattern of GH secretion. Three ewes fitted with indwelling stainless steel cannulae placed in the anterior pituitary gland were consecutively infused with either ovine or rhIGF-I (2·5 μg/h for 2 h) or vehicle. Plasma GH concentrations were suppressed in 3/3 sheep from 1–1·5 h after the commencement of infusion and GH levels remained low for the remainder of the sampling period. In another group of five ewes synergistic effects of IGF-I and IGF-II on GH secretion were tested by icv infusion of rhIGF-I, rhIGF-II, or rhIGF-I+rhIGF-II (5 μg/h for 2 h) or vehicle (sterile 10 mm HCl/saline). Each sheep received each treatment in a randomised design. Infusion (icv) of IGF-I and IGF-II alone or in combination failed to alter GH secretion. These observations suggest that IGF-I derived from peripheral tissues may modulate GH release at the pituitary level but that IGF-I acts neither alone nor in conjunction with IGF-II as a negative feedback regulator of GH secretion via the hypothalamus in the ewe. Journal of Endocrinology (1995) 144, 323–331

The accreditation of laboratories for carrying out calibration and testing is increasingly recognized internationally as an effective means of raising the quality of performance of such laboratories and, through the medium of accreditation standards, a means of international intercomparison of testing and calibration competence. The majority of developed countries have established national accreditation services and many others are in the throes of setting them up. In the United Kingdom the National Measurement Accreditation Service (NAMAS) was established in 1985 by the amalgamation of the National Testing Laboratory Accreditation Service set up in 1981, and the British Calibration Service set up in 1966. To date, NAMAS has handled some 1500 accreditations. This experience, long and extensive by international standards, has put NAMAS in a pre-eminent position in the international league and the NAMAS practices have been used as a model by many other accreditation services.

The effect of hypothalamopituitary disconnection (HPD) on growth hormone (GH) secretion was studied in sheep. Plasma GH levels were measured in serial blood samples (10 min x 6-8 h) taken from 12 Romney wethers and 5 ewes which had undergone HPD 40-506 days earlier and from 4 wethers (10 min x 7 h) to serve as controls. Five wethers and 5 ewes were taken approximately 300 days after HPD and injected with vehicle or 10 micrograms/kg of the synthetic hexapeptide growth hormone-releasing peptide 6 (GHRP-6); GH responses were monitored. In a second series of sheep, 4 wethers and 6 HPD wethers were given saline, 0.5 micrograms/kg of synthetic growth hormone-releasing factor (GRF) or 5 micrograms/kg GHRP-6 and were blood-sampled to measure the plasma GH response. A further group of 4 HPD wethers and 3 control wethers were killed and the anterior pituitary glands collected for the quantification of GH and LH beta mRNA by Northern analysis. Three HPD wethers and 1 HPD ewe and 1 control ewe were killed and their brains were perfused; the hypothalami were sectioned and immunostained for the presence of GRF-containing fibres in the median eminence. Normal episodic GH secretion was abolished by HPD in both wethers and ewes but plasma values did not fall below the assay detection limit, indicating constitutive secretion. Northern blot analyses showed that the GH mRNA was detectable in HPD wethers at a lower (p0.05) level than in control animals but mRNA for LH beta was undetectable in the HPD wethers. Immunohistochemistry revealed GRF-positive staining in the median eminence of the controls but GRF-positive staining was not seen below the operation site in the median eminence of the HPD animals. In the first series, 3/5 wethers and 3/5 of the ewes responded to GHRP-6 challenge; the magnitude of the response was similar in both sexes. In the second series, responses to GRF were lower (48%) (p0.03) in HPD wethers than in control wethers, and responses to GHRP-6 were much lower (p0.01) than those to GRF in both controls and HPD wethers. These studies show that HPD removes GRF inputs to the pituitary gland and abolishes pulsatile GH secretion in most cases but constitutive non-pulsatile secretion continues. The HPD wether pituitary glands had lower GH mRNA levels than controls. Accordingly, HPD sheep were able to respond to a single injection of GRF although the response was half that seen in control animals.(ABSTRACT TRUNCATED AT 400 WORDS)

This study examined the role of the adrenergic system in the regulation of growth hormone (GH) secretion in sheep. Intravenous infusion of noradrenaline (0.5 microgram/kg per min for 2 hr) totally suppressed plasma GH concentrations. Concomitant treatment of animals with the beta-adrenergic antagonist propranolol completely blocked the noradrenaline-induced suppression of GH. In contrast, intravenous injection of the centrally acting alpha 2-agonist clonidine (2 micrograms/kg) elicited a release of GH. To further investigate the central adrenergic regulation of GH secretion 10 micrograms of noradrenaline or adrenaline was microinjected (1 microliter) directly into the preoptic area of the hypothalamus of ovariectomized ewes. When the time of injection coincided with a GH trough period, both noradrenaline and adrenaline caused an increase in plasma GH concentrations, whereas if the injection coincided with an endogenous pulse of GH no additional GH response was obtained. In conclusion, these results provide evidence for the involvement of the adrenergic system in the regulation of GH secretion in sheep. Centrally, adrenergic pathways exert a stimulatory effect on GH release via an alpha 2-adrenergic system, whereas peripherally adrenergic pathways exert an inhibitory effect via beta-adrenergic mediated mechanisms. Furthermore, adrenergic stimulation of the preoptic area may inhibit somatostatin activity and directly facilitate a GH pulse. Alternatively, adrenergic innervation of the preoptic area may influence neurons (somatostatin or other) that project to the arcuate nucleus and stimulate the release of GH-releasing factor.

Hardware, software, and procedural details are presented for creation of a personal computer-based dichotic listening test. The source code is in Microsoft QuickBasic 4.5 and incorporates subject instructions, a practice-to- criterion routine, and automated stimuli presentation and scoring. The original computer platform was an 80286-based computer with a VGA card but the code has been tested with 80386 and 80486 microprocessors and various video modes with no problems. The stimuli are digitized analog signals and are presented through Antex processing cards. Source code and stimuli files are available from the authors. Hearing, Selective Attention, Dichotic Listening, Automated Testing.

The bioavailability of controlled-release morphine 30-mg tablets (MSC) administered orally or rectally and immediate-release morphine (RMS) 30-mg suppositories per rectum, was compared in this 14-subject, randomized, single-dose, analytically blinded, crossover study. Rectal MSC plasma morphine area under the curve from 0-24 hours (AUC0-24) was 50.8% of RMS and was similar for MSC administered by either route (rectal MSC = 90% oral MSC). Rectal MSC had a significantly delayed time to peak plasma level (5.4 vs 1.07 and 2.5 hrs for rectal MSC vs RMS and oral MSC, respectively) and a significantly attenuated time to maximum concentration (6.1 vs 25.4 and 9.7 ng/ml, respectively). Proctoscopy 24 hours after insertion revealed seven instances of mild, transient mucosal erythema or edema with rectal MSC and 12 with RMS. The number of nonlocal adverse effects was 14 with rectal MSC, 19 with RMS, and 18 with oral MSC. Further studies must determine the therapeutic consequences of pharmacokinetic differences and establish guidelines for rectal MSC use. The product is currently not recommended by the manufacturer for rectal administration.

Following an initial proposal from the National Physical Laboratory (NPL), an intercomparison programme on low cycle fatigue (LCF) testing was established in 1984 under the auspices of the Community Bureau of Reference (BCR) of the European Commission. Mr. G.B. Thomas, chairman of the LCF working party of the High Temperature Mechanical Testing Committee (HTMTC) and Dr. C. Amzallag, on behalf of the French working group on LCF, agreed to prepare guidelines for the procedures to be used in test programmes. These were based on the procedures used in previous French intercomparisons and modified on the basis of the draft of the HTMTC code of practice. 1,2 The guidelines were circulated to prospective participants and re-issued in revised form in 1985 in response to comments received.

A 26-year-old white woman had premature rupture of membranes at 35 weeks' gestation. Cervical specimens initially demonstrated group B streptococci and Chlamydia trachomatis. Amniocentesis was performed and the amniotic fluid was positive for chlamydia by direct fluorescent antibody stain. The Gram stain was negative. The patient had an elevated white blood cell count. Labor was induced because of suspected chorioamnionitis. A 2120-g female infant was delivered with an Apgar score of 9 at 1 and 5 minutes. The infant's eye and nasopharyngeal specimens were positive for chlamydia by direct fluorescent antibody stain. After delivery, both Ureaplasma urealyticum and C trachomatis were isolated from the amniotic fluid and fetal membranes. This is the first reported case of chlamydial isolation in amniotic fluid.

Current Navy flight helmets do not provide sufficient passive sound attenuation of the high‐intensity, low‐frequency noise present in some naval aircraft. As part of a program to provide improved hearing protection for aviators and aircrew personnel, the Naval Aerospace Medical Research Laboratory conducted sound attenuation evaluations of four helmet‐integrated active noise reduction (ANR) systems. Sound attenuation measurements (passive attenuation and combined passive/active attenuation) were obtained on Navy and Marine Corps student aviators wearing the prototype helmets in a laboratory noise environment. A Knowles miniature microphone was used to obtain sound levels at the subject's ear. Three sets of measurements were obtained on each subject for each of the prototype systems. A comparison of the combined passive/active attenuation measurements with the passive attenuation measurements reveal increased sound attenuation at 125,250, and 500 Hz and decreased attenuation at 1000 and 2000 Hz. Speech int...

Load- or strain-controlled cycles have been used to assess the low-cycle fatigue behaviour of the wrought Ni-Cr-base alloy IN 597, mainly at 850°C. Very large reductions in cyclic endurance were produced by the introduction of tensile dwell periods. Dwell periods of only a few seconds duration changed the mode of fracture from transcrystalline to predominantly intercrystalline with extensive grain boundary cavitation. Evaluation of the data by existing analytical procedures showed that a simple fractional life expression was suitable for both load- and straincontrolled cycling and gave cyclic endurance predictions within a factor of ± 2. Quantification of microstructural damage provided evidence supporting the fractional life concept.

The low-cycle fatigue performance of the Ni-Cr-base alloys IN597 and IN738 has been examined with particular reference to the creep-fatigue interaction. Results are reported showing a systematic effect on life of IN597 of the level of tensile stress during tests involving cycles with dwell periods. For both alloys the simple life fraction rule correlates the data in a fairly satisfactory manner but some method of stress compensation is necessary for the strain range partitioning (SRP) method. Certain limitations of the SRP method in dealing with results from highly creep resistant alloys are discussed.

Description illustree de la larve au dernier stade de Baetis cleopatrae n. sp., rencontree dans le delta du Nil (Egypte). Cette espece appartient au groupe atrebatinus et presente des affinites morphologiques avec B. balcanicus Muller-Liebenau & Soldan. 1981.

Une espece nouvelle, Baetis albinatii nov. sp., est decrite (imago mâle et larve au dernier stade) a partir de materiel recolte en Corse. Elle appartient au groupe muticus et est tres voisine de B. navasi Muller-Liebenau, 1974.

Ce travail donne une liste de 33 especes de Tipulidae s. s. recoltees a l'etat imaginal dans l'environnement immediat d'une quarantaine de cours d'eau du Sud-Ouest de la France.

19 imagos de Porricondyla ramadei n. sp. ont ete obtenues par elevage. Biotope : des touffes de Bryophytes immergees en eau agitee, dans un torrent des Hautes-Pyrenees a 1 260 m d'altitude. Le prelevement totalisait par ailleurs plusieurs centaines d'invertebres d'especes considerees comme franchement torrenticoles.

The long-term negative feedback effects of sustained elevations in circulating estradiol and progesterone on the pulsatile secretion of gonadotropin-releasing hormone (GnRH) and luteinizing hormone (LH) were evaluated in the ewe following ovariectomy during the mid-late anestrous and early breeding seasons. GnRH secretion was monitored in serial samples of hypophyseal portal blood. Steroids were administered from the time of ovariectomy by s.c. Silastic implants, which maintained plasma concentrations of estradiol and progesterone at levels resembling those that circulate during the mid-luteal phase of the estrous cycle; control ewes did not receive steroidal replacement. Analysis of hormonal pulse patterns in serial samples during 6-h periods on Days 8-10 after ovariectomy disclosed discrete, concurrent pulses of GnRH in hypothalamo-hypophyseal portal blood and LH in peripheral blood of untreated ovariectomized ewes. These pulses occurred every 97 min on the average. Treatment with either estradiol or progesterone greatly diminished or abolished detectable pulsatile secretion of GnRH and LH, infrequent pulses being evident in only 3 of 19 steroid-treated ewes. No major seasonal difference was observed in GnRH or LH pulse patterns in any group of ewes. Our findings in the ovariectomized ewe provide direct support for the conclusion that the negative-feedback effects of estradiol and progesterone on gonadotropin secretion in the ewe include an action on the brain and a consequent inhibition of pulsatile GnRH secretion.

240 imagos appartenant a 31 especes de Limoniidae et une espece de Ptychopteridae sont citees de l'environnement immediat de cours d'eau, jusqu'a 2 200 m d'altitude. 21 especes sont nouvelles pour la Faune de France, 5 autres pour celle des Pyrenees Francaises. Une synonymie est proposee.Les larves de Pseudolimnophila sepium, Idiocera (Protogonomyia) limbata, Molophilus bifidus, M. flavus et Ptychoptera paludosa sont signalees pour la premiere fois dans des biotopes d'eau courante.

Description illustree (antenne, aile, terminalia) des imagos mâle et femelle d'Antocha (s. str.) Phoenicia n. sp., proche d'A. vitripennis (Meigen, 1830) ; redescription des imagos ♂ et ♀ d'A. (s. str.) libanotica Lackschewitz, 1939.

John Rawls' use of a contractarian strategy for justifying basic principles of justice has raised the hope that a similar strategy might work for a theory of right and moral principles generally. I want to show that this hope cannot be fulfilled. In what follows I interpret contractarianism in a Rawlsian way on the grounds that his is the most plausible version of the doctrine we are likely to get. I am not however concerned with the details of Rawls' argument for justice but instead with an idea that appears to underlie the contractarian strategy. In order to avoid the complications of Rawlsian exegesis, I choose to discuss the doctrine as it might be used to justify a moral principle of mutual assistance and not as Rawls in fact uses it to justify principles of justice. My argument cannot be applied directly to Rawls' account of justice without showing that the principles of justice are like the principle of mutual assistance in ways relevant to my argument, and this I have not tried to do. Nevertheless, insofar as I have succeeded in showing an incoherency in the very idea of a contractarian justification of one important moral principle, I will also have built a prima facie case against a contractarian justification of other moral principles, including principles of justice. According to Rawlsian contractarianism, morality is a part of the theory of rational choice: a moral principle is rationally justified or explained to the extent that it can be shown to be prudentially rational for self-interested beings to choose that principle to regulate their social conduct, given a philosophically suitable description of the cir

Fetuses were decapitated in one uterine horn in each of 14 sows at 45 d of gestation. Control (C) and decapitated (D) fetuses were removed by Caesarean section from three sows at 65 d of gestation (total of 10 D and 10 C fetuses), two sows at 85 d (six D and six C fetuses) and nine sows at 110 d (nine C and nine D fetuses) of gestation (Exp. 1). In Exp. 2, four to six fetuses were removed from each of two Ossabaw (O) gilts and three crossbred (C, Landrace X Yorkshire) gilts at 70 d of gestation, from three C and O gilts at 90 d of gestation and from three C and two O gilts at 110 d of gestation. In Exp. 1, one semitendinosis muscle was removed for histochemistry, whereas the contralateral muscle was removed and weighed. A medial portion of biceps femoris muscle was removed and used for histochemistry in Exp. 2. In both experiments, transverse sections (cryostat) of muscle were stained for lipid, glycogen (PAS) and the following enzymes: acid ATPase, NADH-TR, NADPH-TR, malate dehydrogenase (NAD- and NADP-dependent reactions; MDH), succinate dehydrogenase (SDH), alpha-glycerol phosphate dehydrogenase (with and without NAD; alpha-GPDH), isocitrate dehydrogenase (NAD dependent; ICDH), esterase, lipoprotein lipase and lipase. In Exp. 1, body and muscle weights of the two groups were not significantly different (P greater than .05) at 65 d of gestation, whereas D fetuses were smaller and had lighter weight muscles (P less than .05) at 85 d of gestation.(ABSTRACT TRUNCATED AT 250 WORDS)

L'imago male de Rhithrogena ourika n. sp., recoltee dans le Haut Atlas (Maroc) est decrite et figuree. Il s'agit de la premiere espece de Rhithrogena identifiee en Afrique du Nord.

Des prelevements sur fonds de pierres et de graviers ont ete effectues en 237 stations reparties sur 108 cours d'eau. Atherix ibis a ete recolte jusqu'a 2 200 m d'altitude, Ibisia marginata 1 500 m et Atrichops crassipes 900 m. Les principaux facteurs limitant la repartition des trois especes sont :1) la temperature de l'eau qui doit atteindre en ete un minimum de 13-14 °C pour A. ibis, de 11-12 °C pour I. marginata, de 18-19° C pour A. crassipes ;2) la pente (les ruisseaux sont plus rarement colonises au-dela de 25 %) en correlation directe avec la stabilite des pierres du fond entre lesquelles les larves d'A. ibis et d'I. marginata vivent etroitement inserees. Dans ce biotope precis, une taille reduite et une faible section transversale constituent une facteur favorable a l'installation ou au maintien des especes dans les cours d'eau a forte pente (Hexatoma et Dicranota comparativement a A. ibis, divers Oligochetes comparativement a Eiseniella tetraedra). A. crassipes, essentiellement psammophile, vit en courant lent ou meme temporairement nul ;3) la presence de branches d'arbres a feuilles caduques au-dessus de l'eau, necessaire a I. marginata pour accomplir son cycle de developpement. Cette espece pond sur la face inferieure des feuilles de plusieurs essences, en particulier de Corylus avellana. La tendance a une oviposition collective est nette, la meme feuille pouvant porter jusqu'a plus de 400 pontes.De l'amont vers l'aval on rencontre donc : soit la succession ibis - marginata sous l'action predominante de l'altitude (etages de vegetation), soit, toujours en couvert de feuillus, la succession marginata - ibis par faible temperature estivale a altitude moderee.La nymphose, toujours aerienne, a lieu le plus souvent dans les Bryophytes bordant le cours, a une distance de l'eau de 0,5 a 2 m chez I. marginata, dans les Bryophytes mais aussi dans les graviers emerges chez A. ibis, dans le sable chez A. crassipes. Elle dure de 10 a 12 jours a 19 °C chez A. crassipes.

Description de la larve au dernier stade et des adultes d'Ecdyonurus ifranensis n. sp. Cette espece est plus alticole qu'E. rothschildi.

Description illustree de la larve au dernier stade de Baetis bisri n. sp., rencontree dans le Sud du Liban, B. bisri presente des affinites morphologiques avec les especes du groupe rhodani et en particulier avec B. canariensis Muller-Liebenau, 1971.

Description illustree de la larve au dernier stade de Baetis spei n.sp. Cette espece, rencontree dans le Sud du Liban, presente quelques affinites morphologiques avec B. buceratus Eaton.

Description illustree de la larve au dernier stade et de l'imago mâle de Baetis numidicus n. sp. Cette espece, rencontree dans le Nord de l'Algerie, presente a l'etat larvaire des affinites morphologiques avec B. gracilis Bogoescu et Tabacaru.