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We conducted two case studies testing effectiveness of a soil-borne bacteria, Pseudomonas fluorescens strain D7, in controlling Bromus tectorum (cheatgrass) when mixed with native seeds sown after a fire and when sprayed on a native community with high abundances of B. tectorum. Each case study area (162 ha) compared treatments with D7 present and absent and was replicated four times (20.3 ha each) in a completely randomized design. Response variables (foliar cover, aboveground biomass, and density of B. tectorum; density of sown native plants) were measured pretreatment for the sprayed area and each year for 3 yr after treatment at both study areas and were evaluated as a repeated measures analysis. Foliar cover, biomass, and density of B. tectorum with sprayed or seed mixture applications did not differ between D7-treated and untreated areas at any time within the study (F1,6 ≤ 1.42; P ≥ 0.28). D7 as a seed mixture did not significantly impact densities of native seedlings (F1,6 = 1.27; P = 0.30) at any time during the study. Results contrasted with previous D7 studies that showed effective control of B. tectorum within 3 yr of treatment. Since bioherbicidal methods are being commonly applied, we believe that reporting negative results is important for future meta-analytical studies that provide managers with information on the likelihood for weed-suppressive bacteria to effectively control weeds.

The sagebrush biome in the western United States is home to the imperiled greater sage-grouse ( Centrocercus urophasianus ) and encompasses rangelands used for cattle production. Cattle grazing activities have been implicated in the range-wide decline of the sage-grouse, but no studies have investigated the relationship between the physiological condition of sage-grouse and the presence of grazing cattle. We sampled 329 sage-grouse across four sites (two grazed and two ungrazed) encompassing 13 600 km 2 during the spring and late summer–early autumn of 2005 to evaluate whether demographic factors, breeding status, plasma protein levels, and residence in a cattle-grazed habitat were associated with the stress hormone corticosterone. Corticosterone was measured in feces as immunoreactive corticosterone metabolites (ICM). Males captured during the lekking season exhibited higher ICM levels than all others. Prenesting female sage-grouse captured in a grazed site had higher ICM levels than those in ungrazed sites and prenesting female plasma protein levels were negatively correlated with ICM concentrations. With the use of a small-scale spatial model, we identified a positive correlation between cattle pat count and sage-grouse ICM levels. Our model indicated that ICM levels increased by 2.60 ng · g -1 dry feces for every increase in the number of cow pats found in the vicinity. Management practices will benefit from future research regarding the consistency and mechanism(s) responsible for this association and, importantly, how ICM levels and demographic rates are related in this species of conservation concern.

Intensive microstructure sampling over the southern slope of the Cycladic Plateau found very weak mixing in the pycnocline, centered on a thin minimum of diapycnal diffusivity with K ρ = 1.5 × 10 − 6 m2 s− 1. Below the pycnocline, K ρ increased exponentially in the bottom 200 m, reaching 1 × 10− 4 m2 s− 1 a few meters above the bottom. Near-bottom mixing was most intense where the bottom slope equaled the characteristic slope of the semi-diurnal internal tide. This suggests internal wave scattering and/or generation at the bottom, a conclusion supported by near-bottom dissipation rates increasing following rising winds and with intensifying internal waves. Several pinnacles on the slope were local mixing hotspots. Signatures included a vertical line of strong mixing in a pinnacle's wake, an hydraulic jump or lee wave over a downstream side of the summit, and a ‘beam’ sloping upward at the near-inertial characteristic slope. Because dissipation rate averages were dominated by strong turbulence, ϵ/νN2 > 100, the effect on K ρ of alternate mixing efficiencies proposed for this range of turbulent intensity is explored.

Vegetation change and anthropogenic development are altering ecosystems and decreasing biodiversity. Successful management of ecosystems threatened by multiple stressors requires development of ecosystem conservation plans rather than single species plans. We selected the big sagebrush (Artemisia tridentata Nutt.) ecosystem to demonstrate this approach. The area occupied by the sagebrush ecosystem is declining and becoming increasingly fragmented at an alarming rate because of conifer encroachment, exotic annual grass invasion, and anthropogenic development. This is causing rangewide declines and localized extirpations of sagebrush associated fauna and flora. To develop an ecosystem conservation plan, a synthesis of existing knowledge is needed to prioritize and direct management and research. Based on the synthesis, we concluded that efforts to restore higher elevation conifer-encroached, sagebrush communities were frequently successful, while restoration of exotic annual grass-invaded, lower elevation, sagebrush communities often failed. Overcoming exotic annual grass invasion is challenging and needs additional research to improve the probability of restoration and identify areas where success would be more probable. Management of fire regimes will be paramount to conserving sagebrush communities, as infrequent fires facilitate conifer encroachment and too frequent fires promote exotic annual grasses. Anthropogenic development needs to be mitigated and reduced to protect sagebrush communities and this probably includes more conservation easements and other incentives to landowners to not develop their properties. Threats to the sustainability of sagebrush ecosystem are daunting, but a coordinated ecosystem conservation plan that focuses on applying successful practices and research to overcome limitations to conservation is most likely to yield success.

Predictive modeling and mapping based on the quantitative relationships between a species and the biophysical features (predictor variables) of the ecosystem in which it occurs can provide fundamental information for developing sustainable resource management policies for species and ecosystems. To create management strategies with the goal of sustaining a species such as sage grouse (Centrocercus urophasianus), whose distribution throughout North America has declined by approximately 50%, land management agencies need to know what attributes of the range they now inhabit will keep populations sustainable and which attributes attract disproportionate levels of use within a home range. The objectives of this study were to 1) quantify the relationships between sage grouse nest-site locations and a set of associated biophysical attributes using Maximum Entropy, 2) find the best subset of predictor variables that explain the data adequately, 3) create quantitative sage grouse distribution maps representing the relative likelihood of nest-site habitat based on those relationships, and 3) evaluate the implications of the results for future management of sage grouse. Nest-site location data from 1995 to 2003 were collected as part of a long-term research program on sage grouse reproductive ecology at Hart Mountain National Antelope Refuge. Two types of models were created: 1) with a set of predictor variables derived from digital elevation models, a field-validated vegetation classification, and UTM coordinates and 2) with the same predictors and UTM coordinates excluded. East UTM emerged as the most important predictor variable in the first type of model followed by the vegetation classification which was the most important predictor in the second type of model. The average training gain from ten modeling runs using all presence records and randomized background points was used to select the best subset of predictors. A predictive map of sage grouse nest-site habitat created from the application of the model to the study area showed strong overlap between model predictions and nest-site locations.

Greater sage-grouse (Centrocercus urophasianus) habitat management involves vegetation manipulations to increase or decrease specific habitat components. For sage-grouse habitat management to be most effective, an understanding of the functional response of sage-grouse to changes in resource availability is critical. We investigated temporal variation in diet composition and nutrient content (crude protein, calcium, and phosphorus) of foods consumed by preincubating female sage-grouse relative to food supply and age of hen. We collected 86 preincubating female greater sage-grouse at foraging areas during early (18–31 March) and late (1–12 April) preincubation periods during 2002–2003. Females consumed 22 food types including low sagebrush (Artemisia arbuscula Nutt.), big sagebrush (Artemisia tridentata Nutt.), 15 forb species, 2 insect taxa, sagebrush galls, moss, and a trace amount of unidentified grasses. Low sagebrush was the most common food item, but forbs were found in 89% of the crops and composed 30.1% aggregate dry mass (ADM) of the diet. ADM and species composition of female diets were highly variable between collection periods and years, and coincided with temporal variation in forb availability. Adult females consumed more forbs and less low sagebrush compared to yearling females. Because of higher levels of crude protein, calcium, and phosphorus, forbs were important diet components in comparison with low sagebrush, which had the lowest nutrient content of all foods consumed. Our results indicate that increased forb abundance in areas used by female sage-grouse prior to nesting would increase their forb consumption and nutritional status for reproduction. We recommend that managers should emphasize delineation of habitats used by preincubating sage-grouse and evaluate the need for enhancing forb abundance and diversity.

Microstructure measurements taken on the Monterey Bay continental shelf, within 4 km of the shelf break, reveal a complex mixing environment. Depth- and time-averaged dissipation rates ( e ¯ = 7.4 – 55.8 × 10 - 9 W kg - 1 ) and diapycnal diffusivities ( K ρ ¯ = 6.1 – 37.8 × 10 - 5 m 2 s - 1 ) were elevated above observations made over other continental shelves with no significant topography, but were below those influenced by topographic features. The close proximity of the shelf break/canyon rim, locally generated internal tides, and nonlinear internal waves all contributed to the elevated turbulence. The complex bathymetry associated with Monterey Submarine Canyon allowed an internal tide to be generated at depths greater than 1500 m, as well as at the shelf break. The observed velocity field was normally dominated by upward energy propagation from the local shelf break generated internal tide, but near low tide downward energy propagation from a surface reflection of the internal tide generated below 1500 m was observed. Turbulent dissipation rates were not well parameterized by either the open-ocean Gregg–Henyey model or the recently developed MacKinnon–Gregg shelf model. Like its application on the New England shelf, the MacKinnon–Gregg model had the correct functional dependence on shear and stratification (dissipation increasing with increasing shear and increasing stratification), however, the magnitude and range of values were too small. The most surprising finding was the presence of what we believe to be large, high-aspect-ratio, downslope-propagating nonlinear internal solitary-like waves of elevation. Upon reaching the canyon rim, these waves propagated into deep water and transformed into waves of depression. On the shelf south of the canyon, the waves of elevation accounted for 20% of the observed turbulent kinetic energy dissipation. Off the shelf, where the solitary-like waves changed to downward displacement, their average dissipation increased 10-fold to e ¯ = 2.6 × 10 - 6 W kg - 1 , and accounted for nearly half the dissipation in the upper 150 m.

In the spring of 1988, time series of microstructure and ADCP current profiles were collected at four locations in the North Main Basin of Puget Sound, Washington. Depth and time averages of diapycnal diffusivity 〈 K ρ 〉 at the four stations ( 1.8−67.0×10 −4 m 2 s −1 ) were one to three decades above typical open-ocean thermocline levels. The buoyancy frequency-squared N2 was near open-ocean levels, but unlike the open-ocean where N2≳S2, finescale shear-squared S2 was three to six times N2 over significant portions of the water column at two of the stations. The time and space mean of all measurements ( 〈 K ρ 〉=3.6×10 −3 m 2 s −1 ) is close to inferred vertical eddy diffusivity from a primitive equation model for Puget Sound ( K z =3×10 −3 m 2 s −1 ) (J. Geophys. Res. 96 (1991) 16779). Large time and space variability of Kρ was found, with differences of inter-station, depth–time means over one decade. A simple scaling argument using the observed Kρ suggests significant exchange of mass between the layers of the subtidal flow over the basin's residence time. Additionally, measurements show that local mixing may be comparable to volume-weighted sill mixing in modifying the Main Basin's stratification. Both are contrary to the “advective reach” simplification of fjord dynamics. The mixing levels were dominated by the passage of a mid-depth, southward-flowing density intrusion and what we interpret as a strongly advected, non-linear internal tide. These mechanisms elevated profile-averaged Kρ by more than 10 times background levels, with sustained patches of K ρ ≥1×10 −2 m 2 s −1 . Critical 8-m gradient Richardson numbers (Ri8 20 m) and strong turbulence suggest that shear instabilities dominated the turbulence production, though there was support for double-diffusive convection in the warm core of the density intrusion.

Counterflowing waters of the Black Sea and Mediterranean Sea are mixed by turbulent entrainment processes along their course through the Turkish Straits. In the Bosphorus Strait, the entrainment into the upper layer from below is abruptly increased when the flow is accelerated in the narrower southern reach, where the flow passes through a contraction. In contrast, the lower layer salinity decreases towards the north first by gradual entrainment within the Strait and later at an increased rate in the wide continental shelf region upon exit into the Black Sea. After passing over the sill located north of the Strait, the flow on the continental shelf proceeds in the form of a gravity current following the local slopes. The topography of the shelf region, assembled from various sources of high-resolution surveys and maps, is reminiscent of a river delta. The water properties and thickness of the Mediterranean plume is modified by turbulent entrainment, shelf currents, stratification, bottom friction and slope. The flow first spreads out on the mid-shelf slope, follows the delta features to reach the shelf edge and, finally, cascades down the steep continental slope. Horizontal spreading by convective instabilities and eastward propagation of anomalous properties along the continental slope are characteristic features of the deeper region adjacent to the shelf. The behaviour of the density current is revealed by results obtained from a reduced gravity model, suggesting that the slope and fine-scale features of the bottom topography are crucial elements in determining plume behaviour. The model results are found to be robust to environmental changes and in good correspondence with observed flow features, especially when the topography with realistic fine scales and slope are adequately represented.

Thin thermistor films of chemical composition Ni 0.48 Co 0.24 Cu 0.6 Mn 1.68 O 4 were prepared by metal organic decomposition (MOD). Stock solution that was used for thin-film deposition was prepared by dissolving manganese (III) and nickel (II) acetylacetonates, cobalt acetate and copper nitrate in a mixture of methanol, ethylene glycol and acetic acid. Thin-films were fabricated by either dip-coating or spin-coating. Polycrystalline single-phase cubic spinel was obtained after annealing from 600 to 800°C in air. Smooth and dense thin-films, free from cracks, were formed on aluminosilicate glass, however, the thin-film surface was irregular on fused silica, suggesting that the coefficient of thermal expansion of the substrate plays a crucial role in thin-film morphology. Electrical properties are strongly influenced by the annealing temperature: the resistivity and hopping activation energy vary from ρ (298 K) =9.75 Ω cm and E H =0.139 eV for films annealed at 600°C to ρ (298 K) =1015 Ω cm and E H =0.247 eV for the films annealed at 800°C. The Seebeck coefficient was negative for the films annealed at 600 and 650°C and became positive for films annealed at higher temperatures. Electrical conduction was described in terms of small polaron hopping between Mn 4+ and Mn 3+ cations located in octahedral sites of the spinel structure. Changes of the electrical properties were attributed to the reduction of manganese Mn 4+ →Mn 3+ during annealing at high temperatures.

The diameter - velocity dispersion relation in B, V, and K for three early-type galaxies in the Leo I (M96) group is derived from published photometry and kinematic data. The relations in all three colors have slopes which agree well with those for the Coma cluster. The RMS scatter of the Leo I galaxies in each color is extremely small, consistent with the group's compactness. These relations yield estimates of the Coma-Leo I distance ratio of 9.01 +/- 0.51, 8.77 +/- 0.43, and 8.82 +/- 0.31, respectively, with a weighted mean of 8.84 +/- 0.23. The general agreement among the three colors indicates that the early-type galaxies in Leo I and Coma have similar stellar populations. The Coma-Leo I distance ratio coupled with estimates of the absolute distance to the Leo I group allows the Hubble constant to be determined, free of the uncertainties which arise when working with the Virgo cluster. Several high quality distance estimates are available from a variety of techniques: Cepheids in M96 (Tanvir et al. 1995) and M95 (Graham et al. 1997), surface brightness fluctuations (Tonry et al. 1997), planetary nebulae luminosity functions (Ciardullo et al. 1993), and the luminosity of the red giant branch tip (Sakai, Freedman, & Madore 1996). Adopting a cosmic recession velocity of the Coma cluster in the microwave background frame of 7200 +/- 300 km/s, these distance estimates lead to values of the Hubble constant ranging from 70 to 81 km/s/Mpc, with an unweighted mean of 75 +/- 6 km/s/Mpc., To appear in New Astronomy; 15 pages including 3 figures and 2 tables

When mid-latitude internal waves are at the background state modeled by Garrett and Munk ( J. Geophys. Res. , 80: 291–297, 1975), wave-wave interactions transfer energy to dissipative scales so slowly that instabilities generate overturns not much larger than the scales at which viscosity dissipates the turbulence. Consequently, high wavenumber spectra contain only the viscous decay portion of the universal turbulent spectrum. Increases in low-wavenumber shear above background produce larger overturns and turbulence sufficiently intense to form well-developed inertial subranges. The turbulent region of the vertical spectrum is separated from the wave region by a k 3 −1 rolloff that does not vary with the amplitude of low-wavenumber shear, indicating that the wave field is saturated. At low latitudes, internal wave shear is generally more intense than at mid latitudes, but the turbulence is similar to that found with mid-latitude waves at background. Dynamically, the anomaly implies that wave-wave interactions transfer energy to dissipative scales more slowly at low latitudes than at high latitudes. Kinematically, this anomaly results from steeper slope in the rolloff range.

In order to understand the daily cycle of heat storage within the surface mixed layer it is necessary to distinguish between the mixed layer, the zone of relatively homogeneous water formed by the history of mixing, and the mixing layer, the zone in which mixing is currently active. We compare surface layer definitions based on density (or temperature) with turbulence measurements to evaluate their skill in finding mixed and mixing layer depths, using definitions based on density increase from the surface, and on density gradients. Both types of definition are capable of finding the mixed layer depth, with some tuning for local conditions. Neither definition, however, gives mixing layer depths consistently matching the turbulence measurements, although density differences give more stable results. Measurements of turbulent dissipation rates or overturning length scales often yield consistent estimates of mixing layer depths, but there are cases where overturning lengths give distinctly better results. We conclude that overturning length scales give the most reliable measure of mixing layer depth, although conventional shipborne CTDs are seldom capable of sufficiently resolving the overturns.

T he June 2006 edition of Rangelands provides an opportunity for us to highlight a couple of points about the role of peer review in nontechnical publications produced by the SRM. This wildlife-themed issue was thought-provoking, informative, and for the most part accurate in its portrayal of some wildlife conservation issues facing resource managers. However, the articles by Schroeder et al' and Brunner2 regarding sagegrouse help illuminate 2 points about SRM's nontechnical publications: 1) the need for a rigorous peer-review process in publishing issue papers, and 2) the need to clearly separate peer-reviewed literature from editorial pieces in Rangelands. In the Viewpoint article by Schroeder et all, the authors provide a detailed critique of the SRM Issue Paper titled "Ecology and Management of Sage-Grouse and SageGrouse Habitat."3 Their assessment revealed many legitimate problems with the information presented in the issue paper, such as the lack of references for stated facts and unsupported interpretations of existing data. These problems stemmed largely from the issue paper review and publication process. To our knowledge, the issue paper did not undergo formal and rigorous peer review by experts in the field of sage-grouse and sage-grouse habitat. SRM's Wildlife Habitat Committee (WHC) was informally given the opportunity to provide information on sage-grouse, but surprisingly was not intimately involved in developing or approving the issue paper. At the 2006 SRM annual meeting in Vancouver, the WHC discussed the fundamental problems with the issue paper publication process. As a committee, we made a request to the SRM Board of Directors to develop a formal process for the publication of issue papers that includes peer review. We commend the Board for quickly adopting guidelines for the development of issue papers that should improve the rigor of these nontechnical publications. The issue paper guidelines are now posted on the SRM website at: ww. rangelands.org/publications_issuepapers.shtml. Disseminating nontechnical information on species of c ncern, such as sage-grouse, is highly important and valuable if done in a scientifically sound manner. However, as Schroeder et al' point out, we have a responsibility as scientists to present material based upon the best-available and most current research, which includes peer-reviewed literature from inside and outside SRM. The SRM Sage-grouse Issue Paper3 serves as a good example of why we need to use a rigorous peer-review process for widely distributed nontechnical publications that represent SRM as a scientific society. Our second point regarding peer review in nontechnical publications can be made by critiquing the article by Brunner2 titled "Sage-Grouse at the Crossroads" that appeared in Rangelands. This article was not identified as having been peer reviewed, but it did appear in the "Feature Articles" section alongside peer-reviewed papers. Unfortunately, much of the information presented by Brunner2 on sage-grouse biology, habitat requirements, and relationships to domestic lives ock grazing is not supported by scientific research. It is impossible, though, for individuals unfamiliar with sage-grouse biology and management to know whether the assertions are based on science, anecdote, or opinion because statements of fact are made with no literature citations. Brunner2 also provides inaccurate information on the potential effect of the Endangered Species Act (ESA) on private landowners. The article states that "A landowner simply cannot afford to have an endangered or threatened species on his land. He faces $75,000 fines plus jail time if a bird is 'harassed', ie, flushed as the person drives over his own land." This statement is false; criminal penalties under Section 11 of the ESA4 can only be imposed for those who "knowingly violate" its prohibitions, which can include harassment. These statements are concerning given that many of us in SRM work with farmers and ranchers every day to improve habitat for species of concern while keeping the goal of agricultural production at the forefront. Endangered species conservation

The reaction of Pt(C 2 H 4 ) 2 (PCy 3 ) with (OC) 4 M(μ-H)(μ-P n Pr 2 )Pt(CO)(PCy 3 , ( 1 : M  Cr, Mo, W) occurs in a highly specific, kinetically controlled manner to give MPt 2 (μ 2 M  Pt -CO)(η 2 Pt  Pt -H)(μ 2 M  Pt -P n Pr 2 )(CO) 4 (PCy 3 ) 2 ( 5 ), as the first formed trimer. The trimer 5 (M  Mo, W) isomerizes to give MPt 2 (μ 2 Pt  Pt -CO) ((μ 2 M  Pt H)(μ 2 M  Pt -P n Pr 2 )(CO) 4 )PCy 3 ) 2 ( 6 ) which in turn isomerizes to MPt 2 μ 2 M  Pt CO)(μ 2 M  Pt (μ 2 Pt  Pt -P n Pr 2 )(CO) 4 (PCy 3 ) 2 ( 7 , as the final isolable product. These results provide a detailed insight into the mechanism of “Pt(PCy 3 ) addition”, a cluster assembly process.

The cationic complex [η5-Cp(OC)(η2-allene)Fe(PPh2H)]PF6 reacts with Pt-(C2H4)(PPh3)2 via C2H4 substitution (rather than oxidative addition of the PH bond) to give [η3-(2-η5-Cp(OC)(PR3)Fe-allyl)Pt(PPh3)2]PF6 PR3 = PPh2H the structure of which has been determined by a single crystal X-ray diffraction study of its dimethylphenylphosphine analog [Pr3 = PMe2Ph]. Crystal data: [C53H50FeOP3 Pt+] [PF6−]·2[C6H6] is triclinic, space group P1 with a 13.504(2), b 14.044(6), c 17.759(4) A, α 98.05(2), β 108.59(1), γ 104.44(2)°, U 3002(3) A3, Z = 2, Dx 1.49 Mg m−3, λ(Mo-Kα) 0.71069 A, μ 27.6 cm−1, F(000) = 1356, T 298 K, R = 0.0527 (Rw = 0.0575) for 7731 observed (I > 3σ(I) reflections. The compound contains an ordered η2-η1-Fe, η3-Pt allyl moiety with PtC distances of 2.151(9) and 2.165(8) A to the terminal atoms and 2.272(7) A to the central atom; the FeC distance is 1.967(7) A. The plane of the allyl group is canted at an angle of 122.5° with respect to the PtP2 plane. The Pt…Fe separation is 3.794(1) A.

Morbidity and surveillance data on viral hepatitis cases in the United States since 1970 has revealed plateauing of case rate, continued failure to observe seasonal variation, more general geographic distribution of cases, and persistence, although at progressively lower levels, of highest rates in males 15-29 years of age. Based on results of HBS Ag testing, as much as 24 per cent of hepatitis B may be misdiagnosed by physicians and from 18 to 46 per cent of reported cases can be classified hepatitis B, thus suggesting that hepatitis B may account for up to one-half the recognized viral hepatitis in this country. HBS Ag-negative hepatitis still seems commonly acquired through close personal contact; hepatitis B patients 15-29 years of age also commonly have personal contact association. Parenteral drug abuse and transfusion of blood and blood products continue to play a role in dissemination of hepatitis B, but hepatitis B seems to account for only about one half of all reported transfusion-associated hepatitis. Case fatality rates for reported cases appear to increase with age but are not higher for HBS Ab positive patients than for negative patients.

An investigation of hepatitis in personnel at a university hospital revealed 79 cases of viral hepatitis, type B, between January 1968 and August 1972. Thirty-four cases occurred in staff who worked on the renal ward and hemodialysis unit, and 34 in personnel who worked in the clinical laboratories. The number of cases correlated temporally with the number of hepatitis B surface antigen (HBsAg)-positive patients undergoing hemodialysis in the hospital. Clinical hepatitis attack rates and hepatitis B antibody prevalence rates correlated with exposure to blood from patients with renal disease, including those who received transplants, both in the renal ward and in the clinical laboratories. Transmission was thought to be by accidental and inapparent parenteral routes involving infective blood from patients with renal disease who were chronic carriers of HBsAg. A control program designed to prevent further cases of hepatitis was instituted. The potential of epidemic viral hepatitis is a serious problem in institutions providing hemodialysis.

Prominent thermohaline staircases, extending vertically for hundred of meters, have been found in only fewew locations in teh oceanic thermocline. Their unique structure and their resemblance to staircases formed in laboratory salt fingerinn lead to an immediate identification with double diffusion. Nevertheless, little has een known about the intensity and structure of mixing in the staircases. Recent observations with the Multi-Scale Profiler (MSP) reveal the layers to be in slow, steady relative motion and to have very low leverls of e, the rate of viscous dissipation of turbulent kinetic energy. Because of the strong shear, the fingers appear to be strongly inclined o the horizontal and to produce low buoyancy fluxes into the layers.

Summary The IgM and IgG make-up of the antirabies antibody response was studied in thirty-nine individuals who received a full course of duck-embryo-derived antirabies vaccine. The IgM response was shown to be greatly prolonged making up 79% and 47% of 'the total antirabies antibody response on the 13th and 27th days after initiation of immunisation, respectively. The prolongation of the IgM response was felt to be due to persistence of antigen caused by the 14 daily shots of vaccine. Since IgM antibody does not leave the circulation and cannot get to tissue sites where it is needed, it is suggested that this response—and, hence, this schedule of immunisation—need modification. Such a modification would be designed to permit the more rapid appearance of high of IgG antirabies antibody.