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As natural resource managers continue to face complex problems, cross-boundary stewardship among multiple jurisdictions becomes increasingly important. Cooperation is one strategy for achieving ste...

Floating artificial structures provide sites for fouling communities and favourable habitat for the establishment of non-indigenous species. Two species of Tanaididae dominated crustacean biota in a one year time-series sampling of macroalgae on the floating dock at the West Beach boat ramp, Adelaide, South Australia. This paper provides identifications for these two species and discusses inter- and intra-species variability considering the available body of morphological and molecular information. We have given one species a new species designation, Tanais adelaidensis n. sp. The other has a 655 nucleotide CO1 sequence matching that of Hexapleomera sasuke Tanabe & Kakui, 2019 collected in Japan, also matching a shorter CO1 sequence for a described Zeuxo Templeton, 1840 species from the Eastern Mediterranean. This work underlines the utility and need for detailed morphological and molecular data to resolve the taxonomy and biogeography of fouling and holdfast community tanaids, particularly those that have the demonstrated potential for a history of transport between geographically distant sites.

The boundaries of most protected areas are not large enough to encompass natural processes such as hydrologic and ecological connections between wetlands and within watersheds. Therefore, management is likely to be improved by working across boundaries with multiple jurisdictions. This research explores barriers and opportunities for cross-boundary cooperation for wetland stewardship in Rocky Mountain National Park (RMNP), Colorado, USA, and surrounding areas, using semi-structured interviews with staff members of government agencies, nonprofits, research organizations, and municipalities. Results show that wetlands outside of RMNP are experiencing similar cross-boundary disturbances to those within the park. Although participants recognize that working cooperatively with neighboring jurisdictions can decrease the effects of boundaries on wetland integrity, they also reported that the most significant cross-boundary challenge is working with others to exchange resources, develop a common goal, and implement projects cooperatively. We provide recommendations on how to address cooperative management challenges while taking advantage of opportunities to facilitate cross-boundary wetland stewardship at the ecosystem-scale.

Southern Torrent Salamanders (Rhyacotriton variegatus) range widely from north coastal Oregon to northern California but are a patchily distributed inhabitant of forested seeps and headwater springs. We collected bimonthly samples of this species from managed forest sites in the Mad River watershed, Humboldt County. Larvae were measured, marked, and released, but a limited number of transformed individuals were preserved for laboratory analyses. North coastal R. variegatus breeds annually and has an extended courtship and egg-laying period. Cloacal spermatophores were present in gravid females from February through June, and oviposition likely occurs spring through fall. A prolonged larval period (hatching to metamorphosis) lasts 2–2.5 yr; transformed females require another 1.5–2 yr until first breeding, and clutch size averages 7.5 eggs. Adult sizes, size at metamorphosis, and developmental times were comparable to north coastal Oregon R. variegatus, suggesting that a simple north-south, harsh-...

Female salamanders in the suborder Salamandroidea store sperm in cloacal glands called spermathecae. Scanning electron microscopy was used to study these glands in females of the Southern Torrent Salamander, Rhyacotriton variegatus (Rhyacotritonidae), from northern California. Sperm initially enter the cloaca in a tangled mass from the spermatophore cap, but within the spermathecal tubules, small groups become aligned along their long axes. Sperm nuclei typically are embedded in apical microvilli of the secretory cells forming the distal acini of the spermathecae. Junctional complexes between apices of adjacent epithelial cells are occasionally broached or otherwise absent, and sperm can be found in the intercellular canaliculi between such cells. Spermathecae of R. variegatus are simple glands that branch off a tube extending dorsally into cloacal tissue. This spermathecal anatomy is in-between that of the Plethodontidae, which have a compound tubuloaveolar gland as the single spermatheca, and other salamandroids, in which sperm storage occurs in numerous simple tubular glands, each one a spermatheca. Sperm associations in the simple spermathecae of R. variegatus, however, are most similar to those reported for plethodontids.

As patients become more involved in decisions affecting their health, it is important to monitor and improve the support clinicians provide to facilitate shared decision making. The Decision Support Analysis Tool (DSAT) was developed as a research tool to evaluate practitioners' use of decision support and related communication skills during a clinical encounter. The DSAT, consisting of six categories of decision support skills and four categories of communication skills, was tested with 34 actual transcripts of patient-physician dialogue. The patients were prepared for the clinical encounter with either a detailed decision aid plus worksheet (n=16) or a pamphlet (n=18). Pairs of raters, blinded to the intervention allocation, coded each transcript independently. The overall inter-rater agreement and kappa coefficients were, respectively 75% and 0.59 for the decision support skills and 76% and 0.68 for the communication skills categories. The frequency of DSAT skills coded: (a) were significantly correlated with three out of six patient and physician outcome measures (r>0.30, P

France implemented a comprehensive smoke-free policy in public places in February 2007 for workplaces, shopping centres, airports, train stations, hospitals and schools. On January 2008, it was extended to meeting places (bars, restaurants, hotels, casinos, nightclubs). This paper evaluates France's smoke-free law based on the International Tobacco Control Policy Evaluation Project in France (the ITC France Project), which conducted a cohort survey of approximately 1,500 smokers and 500 non-smokers before the implementation of the laws (Wave 1, conducted December 2006 to February 2007) and two waves after the implementation (Wave 2, conducted between September-November 2008; and Wave 3, conducted between September-December 2012). Results show that the smoke-free law led to a very significant and near total elimination of indoor smoking in key venues such as bars (from 95.9% to 3.7%) and restaurants (from 64.7% to 2.3%) at Wave 2, which was sustained four years later at Wave 3 (1.4% in restaurants; 6.6% in bars). Smoking in workplaces declined significantly after the law (from 42.6% to 19.3%), which continued to decline at Wave 3 (to 12.8%). Support for the smoke-free law increased significantly after their implementation and continued to increase at Wave 3 (among smokers for bars and restaurants; among smokers and non-smokers for workplaces). The findings demonstrate that smoke-free policies that are implemented in ways consistent with the Guidelines for Article 8 of the WHO Framework Convention on Tobacco Control (WHO FCTC) lead to substantial and sustained reductions in tobacco smoke in public places while also leading to high levels of support by the public.

France implemented a comprehensive smoke-free law in two phases: Phase 1 (February 2007) banned smoking in workplaces, shopping centres, airports, train stations, hospitals, and schools; Phase 2 (January 2008) banned smoking in hospitality venues (bars, restaurants, hotels, casinos, nightclubs). This paper evaluates France's smoke-free law based on the International Tobacco Control Policy Evaluation Project in France (the ITC France Project), which conducted a cohort survey of approximately 1,500 smokers and 500 non-smokers before the implementation of the laws (Wave 1) and two waves after the implementation (Waves 2 and 3). Results show that the smoke-free law led to a very significant and near-total elimination of observed smoking in key venues such as bars (from 94-97% to 4%) and restaurants (from 60-71% to 2-3%) at Wave 2, which was sustained four years later (6-8% in bars; 1-2% in restaurants). The reduction in self-reported smoking by smoking respondents was nearly identical to the effects shown in observed smoking. Observed smoking in workplaces declined significantly after the law (from 41-48% to 18-20%), which continued to decline at Wave 3 (to 14-15%). Support for the smoke-free laws increased significantly after their implementation and continued to increase at Wave 3 (p

The extraction of manganese(II), iron(III), cobalt(II), nickel(II), copper(II), zinc(II) and cadmium (II) from 1.0 M sodium sulphate by LIX 1104 (a hydroxamic acid) was investigated at various aqueous pH values. The extraction order is: Fe(III)>Cu(II)>Zn(II)>Ni(II)≈Co(II)>Cd(II)>Mn(II). Slope analysis and non-linear least-squares regression showed that LIX 1104 formed chelates of the nature ML2 with manganese, cobalt, zinc and cadmium and ML2 (HL) with nickel and copper. LIX 1104 appears particularly useful for the removal of iron (III) from other base metals as it functions in strongly acidic media and does not co-extract acid significantly. It can also be used to separate copper from other base metals.

Henry's Law constants have been measured for a suite of naturally-occurring halogenated methanes (CH 3 Cl, CH 3 I, CH 2 Br 2 , CHBr 2 Cl, CHBrCl 2 , CHBr 3 , CH 2 I 2 and CH 2 ClI) in seawater. The procedure involved equilibrating a gas stream with a temperature-controlled column of seawater containing the compounds of interest at nanomolar concentrations. Temperature dependencies of the constants are reported between 0 and 20°C.

The use of two-phase potentiometric metal extraction titrations to study solvent extraction equilibria is described. The method provides a highly reproducible and convenient manner by which to determine extraction behaviour. The system was tested on a number of acidic extractants, namely D2EHPA, Ionquest 801, Cyanex 272, naphthenic acid and Versatic 10 acid. The extraction from an aqueous nitrate medium of silver(I), copper(II) and cadmium(II) was studied. The potentiometric data were used to obtain extraction curves and elucidate the nature of the extracted complexes by slope analysis and non-linear least squares treatment. In general, the following extraction order was obtained: D2EHPA > Ionquest 801 > Cyanex 272 and naphthenic > Versatic 10 for copper(II) and cadmium(II). Organophosphorus acids were shown to form complexes of the nature of Cu(HA2)2 with copper(II) and carboxylic acids formed dimeric complexes (CuA2(HA))2. With cadmium octahedral complexes of the form CdA2(HA)4 occurred. The extraction of silver(I) by Versatic 10 gave a dimeric complex (AgA(HA))2. HA denotes the extractant in the acid form.

Unialgal nonaxenic cultures of seven species of phytoplankton, including both warm- and cold-water organisms, were examined under halocarbon-clean conditions for the production of CH 3 Cl. Incubations of all species showed CH 3 Cl increases significantly greater than in the control medium. The magnitude of increase varied with the phytoplankton species present and in some cases also with growth stage. Longer time series showed that CH 3 Cl continued to increase after the death of all the phytoplankton cells. Although direct production as a by-product of phytoplankton metabolism cannot be ruled out earlier in the time series, indirect chemical and (or) biotic reaction of algal-associated organic matter is required to explain this continued increase. Characterization of the role of bacteria in both pre- and postsenescent stage CH 3 Cl production will require comparable experiments carried out under axenic conditions

Many studies on cool, forested streams have shown that removal of riparian canopy leads to higher incident radiation, blooms in algal and macroinvertebrate populations, and concomitant increases in salmonid abundance. In warm, high-elevation desert streams, however, an open canopy may not increase salmonid density. Our seven study reaches on 3rd-order tributaries of the John Day River in eastern Oregon included riparian areas ranging from denuded, heavily grazed streambanks to intact conifer forest. Average summer solar inputs to these sites varied from 165 to 2230 megajoules/m 2 , and stream temperatures were influenced by the density and extent of canopy. Densities of steelhead trout (Oncorhynchus mykiss) and sculpin (Cottus supp.) decreased significantly with greater incident radiation and higher stream temperatures, although many warm-water cyprinids increased in abundance in unshaded sites. Periphyton standing crops (g ash-free dry mass/m 2 ) closely tracked solar inputs and was, in...

The effect of a commonly used modifier, isodecanol, on the cobalt(II) -chloride system with the tertiary diamine extractants N,N,N’ N’-tetra-n-octylethylenediamine (tetocen) and N,N-di-n-ocryl-2-(aminomethyl)pyridine (pyridioc) was studied. The diamine extractants behave as stronger bases, the extraction of cobalt(II) decreases and chelate extraction mode is enhanced as the alcohol concentration in benzene is increased. The observations have been discussed in terms of changes in the solubility parameter and dielectric constant of the diluent and the solvation energy and solubility of the solute.

The extraction of sulphuric acid using binary extractants is reported. The binary extractants studied consisted of equimolar mixtures of the organophosphorus acid extractants D2EHPA, PC-88A and Cyanex 302 and the amine-type extractants Alamine 336, Aliquat 336, Adogen 283 and Primene JMT. The most efficient loading from a solution initially containing 75 g/l sulphuric was obtained at an organic to aqueous phase volume ratio of 5:1 using a 50% solution of the binary extractant in Shellsol AB. The best binary extractant in terms of extraction efficiency was Alamine 336/D2EHPA. A McCabe-Thiele construction shows that relatively few equilibrium stages are required for efficient extraction. The efficiency of stripping the loaded organic phases with water is poor and the use of a basic stripping solution to increase the stripping efficiency may be necessary.

Cyanex 301, Cyanex 302 and Cyanex 272 were used to extract cobalt(II) and nickel(II) from a sulphate medium in order to elucidate any separation properties these phosphinic acid extractants display. All the reagents extracted cobalt selectively, Cyanex 302 exhibiting better separation characteristics than Cyanex 272, which in turn showed a higher selectivity than did Cyanex 301. The separation (pH0.5Ni-pH0.5Co) found for Cyanex 302 was 2.6 pH units, compared to 1.7 pH units for Cyanex 272 and 1.1 pH units for Cyanex 301. Based on these results and the fact that Cyanex 301 would need strong acid to strip it, an experiment was conducted using Cyanex 302 and Cyanex 272 to separate cobalt(II) and nickel(II) from a solution containing 100 g/l NiSO4·6H2O and 2 g/l CoSO4·7H2O with favourable results. Vapour pressure osmometry was used to determine the degree of aggregation of the extractants in toluene. Both Cyanex 272 and Cyanex 302 are dimeric and Cyanex 301 exists as a monomer. Slope analysis methods were used to determine the nature of the cobalt(II) and nickel(II) complexes extracted.

The extraction behaviour of Cyanex 301, Cyanex 302 and their binary extractant mixtures with Aliquat 33b towards copper(II), zinc(II), iron(III), iron(II), cobalt(II), nickel(II) and manganese(Il) is indicated. The extraction data were collected from sulphate solutions with acidities ranging from pH 10 to 8 mol/dm3 sulphuric acid. Cyanex 301 is a more efficient extractant than Cyanex 302 and is able to effect extraction at greater acidities. In combination with the organic base Aliquat 336 the extraction power of these extractants is lowered and in some cases the extraction is suppressed appreciably. However, the suppression of extraction can be useful in metal separation and affords greater control over the back-extraction. The suppression is ascribed to the high stability of the acid-base couple which must dissociate in order to effect extraction.

The extraction of cobalt(II) from a chloride medium (pH 1 to 5) by N,N,N1,N1-tetra-n-octylethylenediamine, N,N-di-n-octyl-2-(aminomethyl)pyridine, Alamine 336 and Aliguat 336 dissolved in 5% isodecanol - benzene was investigated. The protonation constants of the tertiary amine extractants are reported. They were obtained using the program SUPERQUAD in conjunction with the electrode calibration program MAGEC. The nature of the extracted complexes was elucidated using spectrophotometric methods, including the program TRIANG. Extraction equilibria are proposed based on these results. Gaussian analysis was employed to resolve the spectra of the extracted complexes in order to obtain estimates of the concentrations of the individual extracted complexes. These estimates were utilized in a non-linear least squares curve-fitting procedure to obtain extraction constants for the proposed extraction equilibria.

Objectives The purpose of our study was to assess the risk of cardiovascular disease (CVD) mortality in a Canadian cohort of 337 397 individuals (169 256 men and 168 141 women) occupationally exposed to ionizing radiation and included in the National Dose Registry (NDR) of Canada. Material and methods Exposure to high doses of ionizing radiation, such as those received during radiotherapy, leads to increased risk of cardiovascular diseases. The emerging evidence of excess risk of CVDs after exposure to doses well below those previously considered as safe warrants epidemiological studies of populations exposed to low levels of ionizing radiation. In the present study, the cohort consisted of employees at nuclear power stations (nuclear workers) as well as medical, dental and industrial workers. The mean whole body radiation dose was 8.6 mSv for men and 1.2 mSv for women. Results During the study period (1951-1995), as many as 3 533 deaths from cardiovascular diseases have been identified (3 018 among men and 515 among women). In the cohort, CVD mortality was significantly lower than in the general population of Canada. The cohort showed a significant dose response both among men and women. Risk estimates of CVD mortality in the NDR cohort, when expressed as excess relative risk per unit dose, were higher than those in most other occupational cohorts and higher than in the studies of Japanese atomic bomb survivors. Conclusions The study has demonstrated a strong positive association between radiation dose and the risk of CVD mortality. Caution needs to be exercised when interpreting these results, due to the potential bias introduced by dosimetry uncertainties, the possible record linkage errors, and especially by the lack of adjustment for non-radiation risk factors.

The potential of the chelate extraction mode displayed by diamine extractants is illustrated by using two tertiary diamine extractants to extract palladium(II) and platinum(IV) from a base metal solution containing copper(II), nickel(IT), cobalml) and iron(III) in 1 mol/dm3lithium chloride. The extraction behaviour of the diamine extractants is compared with that of the commercially-available extractants Alamine 336 (a tertiary monoamine extractant) and Aliquat 336 (a quaternary monoammonium chloride salt). By exploiting the chelate extraction mode, specific to diamine extractants, separation of palladium(IT) from platinum(lv) can be achieved. The only base metal ion that is extracted is iron(III). Iron(III) can be stripped with 1 mol/dm3sulphuric acid or the extraction can be performed under mildly acidic conditions, e.g. pH 4.7. Under the latter conditions ironflll) precipitates quantitatively as a hydroxide complex and can be removed by filtration. The selective back-extraction of palladium(II...

An elaborate drainage and water quality research project, consisting of 24 adjacent plots, each 75 m long ¥ 15 m wide was established in Quebec. A vertical plastic curtain was installed around the periphery of each plot, to a depth of 2 m below the soil surface, to minimize water and chemical flows between plots. A trenchless drain laying machine with a modified shoe behind the plow was used to install the plastic curtain. The system worked extremely well. It has several advantages compared to traditional methods of curtain installation by backhoe.

Numerous studies have looked at various aspects of organohalogen production by marine macrophytic algae which occupy the coastal zones of the world’s oceans, but only recently has evidence been provided which shows that phytoplankton occupying the vastly greater expanse of open ocean waters can in some instances act as halocarbon sources. The question of such sources in the open ocean is important on account of their potentially large contribution to fluxes of halogens into the atmosphere where they play a significant role in determining the trace chemical composition, and in particular the concentration of ozone. We review evidence for production of volatile organohalogens by marine phytoplankton, and present recent results from our laboratory and from field experiments which were aimed at elucidating this source.

Methyl chloride was measured directly in seawater using a purge and trap system and gas chromatography with electron capture detection. The results indicate that surface waters of the northwest Atlantic are a source of methyl chloride to the atmosphere during late spring/early summer. The average surface concentration was 271 pM (σ = 68 pM), supersaturated with respect to an assumed tropospheric boundary layer mixing ratio of 0.7 ppbv. Elevated concentrations were observed throughout the region in waters above the seasonal thermocline. Near-surface maxima of differing thickness and intensity were also seen within this upper layer. Broad maxima within the 200–800m depth range were associated with water masses more recently subducted from the surface than the surrounding main thermocline waters. Coastal inputs of methyl chloride appear not to be an important source in the area of study. Although there is some indication of elevated concentrations associated with higher phytoplankton activity in shelf edge regions, the picture concerning phytoplankton production of methyl chloride is still unclear. Further work is required to look at direct and indirect mechanisms by which phytoplankton may influence the distribution of methyl chloride in the oceans. The global ocean-to-atmosphere flux estimated from this data set, 3.3 - 4.8 × 1010 mol CH3Cl yr−1 (1.7 - 2.4 × 1012 g CH3Cl yr−1) suggests that the oceans may contribute a smaller flux of methyl chloride to the atmosphere than previously thought.

The free urinary metabolites, homovanillic, indoleacetic and 5-hydroxyindoleacetic acid were measured in 24 h urines obtained from seven highly selected drug-free chronic schizophrenic patients and seven mentally normal control subjects on a low amine diet. Gas chromatography selected ion monitoring of silylated extracts was used to assay each metabolite using its own deuterated form as an internal standard. In the electron impact mode the positive ion fragments used to quantitate the amount of each metabolite in the urine were, respectively, m/z 209/211 for homovanillic acid, 319/321 for indoleacetic acid and 290/292 for 5-hydroxyindoleacetic acid. It was found essential that each compound be assayed using its own deuterated derivative as the internal standard. When expressed per mg creatinine, the homovanillic and 5-hydroxyindoleacetic acid levels of the chronic schizophrenic patients were in the normal range, but indoleacetic acid was slightly and statistically significantly higher, p = 0.01.

Summary. A computer-assisted instruction (CAI) system can provide detailed and immediate feedback following every student response. Two such procedures, labelled ‘active’ and ‘passive’ were designed for helping children to multiply two- and three-digit numbers by one-digit numbers. The active feedback procedure required an overt response to be given to each element in the procedure for computing the answer. The ‘passive’ procedure merely printed a feedback message. Two experiments are described which had treatment conditions of (i) no feedback, (ii) passive, and (iii) active feedback. As well as on-line performances being recorded in detail by the computer, pre-and post-tests were given. Substantial gains on pre-and post-tests were recorded for the feedback groups, and a regression analysis showed that greatest effects were with pupils whose initial level of achievement was low. Overall differences between the two feedback groups did not reach significance. Finally, a simple model to account for multiplication performance is proposed.

Parasympathetic denervation of the rat parotid gland by avulsion of the auriculotemporal nerve caused a marked and lasting decrease in gland weight. Parasympathectomy did not change the levels of choline in the gland but decreased by 60% the levels of acetylcholine (ACh) ten days after surgery and 65% at 28 days. It is puzzling that relatively high levels of ACh remained after parasympathetic denervation. The presence of additional cholinergic nerves that innervate the gland, or pass through it en route to other structures may account for some of the remaining ACh. Also, Schwann cells from denervated nerves might have contributed to some of the ACh. The existence of an extraneuronal source of ACh is considered.

The PARCS CODE calculates the coherent, incoherent, and overdense surface radar cross sections of a rocket plume. The modified Born approximation calculation includes attenuation, local index of refraction, Doppler shift and range cell truncation. The program accepts plume data directly from the AeroChem LAPP code, but may be interfaced with other sources of plume definition.

Martin (10) described the accumulation of choline (Ch) against a concentration gradient by human red blood cells. Later he and his associates (8, 9, 11) reported that lithium treatment strongly inhibited Ch transport in human red cells. Furthermore, the Ch transport system did not recover when red cell ghosts were prepared, a procedure which removed both intracellular as well as extracellular lithium. After a patient was withdrawn from lithium therapy, the Ch transport system in the red cells took about three months to recover. Inasmuch as this time is about the life of red cells in the blood compartment, they suggested that lithium therapy produced an irreversible inhibition of Ch transport. The clinical significance of this startling observation is unknown.

Plasma and red blood cell choline concentrations have been suggested as possible peripheral markers of brain cholinergie dysfunction in various human diseases such as major affective disorders, tardive dyskinesia, Tourette’s syndrome and senile dementia of the Alzheimer’s type (1, 2, 4–8, 10). The present study was initiated to explore these possible relationships in normal human volunteers and patients of similar age. The patients were diagnosed as having tardive dyskinesia or dementia of the Alzheimer’ s type. These patients were relatively old and their diets were difficult to control. Therefore, additional studies were done in rats and monkeys of various age groups where dietary factors could be held constant. The results obtained indicate that plasma and red blood cell choline levels do not correlate with brain dysfunction in either humans or monkeys. However, in these same species, with increasing age, plasma choline levels increase. Interestingly, increased plasma choline was not observed in aging rats.

In a prospective survey of infants born in a single maternity unit, asymptomatic faecal colonisation by Clostridium difficile occurred in 31 (47%) of 66 babies who provided a faecal sample during week one of life and at age 14 and 28 days, and in 46 (30.7%) of the total of 150 babies for whom at least one faecal sample was obtained during the month of study. There was no evidence for acquisition of the organism from the mother during delivery and colonisation was unrelated to the means of delivery, infant sex, means of feeding, duration of hospital stay, or antibiotic treatment. New colonisation occurred throughout the month of the study and further evidence for environmental acquisition was obtained by the finding of a similar strain of C difficile in 7 babies from one ward together with positive environmental cultures. Colonisation was frequently transient and occasionally intermittent; most infants kept the same strain during their period of carriage. Twenty two (47.8%) babies colonised by C difficile had low titres of cytopathic faecal toxin but none had symptomatic diarrhoea or features of necrotizing enterocolitis. The in vitro toxigenic potential of 57 toxigenic isolates from 36 babies was low and 12 babies carried non-toxigenic strains. Transient colonisation by C difficile in early life is almost certainly more common than is generally recognized and the neonate provides an important reservoir of potential infection.

Oral phosphatidylcholine (PC) in a dose of 250 mg/kg choline equivalent, was given 1, 2, 4, 8, 12, and 24 hr prior to brain assay to groups of fasted mice. The animals were then killed by focused microwave irradiation to the head and brain choline (Ch) and acetylcholine (ACh) assayed by chemical demethylation using gas chromatography-nitrogen phosphorous (GC-NP) detection. Mouse brain Ch levels increased significantly at 4 (P less than .001) and 8 (P less than .01) hr after PC administration. However, there was no change in mouse brain ACh. When this experiment was repeated in a second series of animals at 1, 3, 6, and 12 hr pretreatment with PC, only the 6 hr pretreatment showed a significant increase in brain Ch (P less than .01). The effects of PC administration to alter the known ACh depleting effects of scopolamine were also determined by giving PC orally 4 hr before and scopolamine, 0.1, 0.32, and 1 mg/kg, one hr before microwave irradiation. The known depleting effects of scopolamine pretreatment on brain ACh were confirmed (P less than .001). A large dose (1 mg/kg) of scopolamine also caused a decrease in brain Ch (P less than .001). Pretreatment with PC reversed the depletion of brain Ch induced by scopolamine but had no effect on depleted brain ACh. The results indicate that, although mouse brain Ch can be increased by oral PC, there is no effect on mouse brain ACh.

Life history attributes of two populations of Rhyacotriton olympicus were studied in western Oregon. A population in the Coast Range had (1) smaller eggs; (2) smaller metamorphic size; (3) smaller size at maturity; (4) smaller mean adult size; (5) smaller maximum size, and (6) higher fecundity, compared to a population in the Columbia River Gorge. Also, the population in the Coast Range is thought to have smaller hatchlings and lower age at maturity. Females are larger in both populations. Spermatophores were found in females in all months except August, September, December and January, indicating an ex- tended courtship season. Similarly, oviposition may occur at almost any time,, although there is a peak of courtship and egg-laying activity in May in both populations. Data on growth, density and movement of marked larvae are given for the population in the Columbia River Gorge. Females reproduce annually and apparently do not attend the embryos. In many respects, the reproductive mode of R. olympicus is more like that of hemidactyliine plethodontids than other ambys- tomatids.