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Tetrahedrite (Cu12Sb4S13) and famatinite (Cu3SbS4) are good candidates for green energy applications because they possess promising thermoelectric and photovoltaic properties as well as contain earth-abundant and nontoxic constituents. Herein, X-ray photoelectron spectroscopy (XPS), ultraviolet photoelectron spectroscopy (UPS), and electron paramagnetic resonance spectroscopy (EPR) methods examined inherent electronic properties and interatomic magnetic interactions of Cu-site doped tetrahedrite and famatinite nanomaterials. An energy-efficient modified polyol method was utilized for the synthesis of tetrahedrite and famatinite nanoparticles doped on the Cu-site with Zn, Fe, Ni, Mn, and Co. This is the first parallel study of tetrahedrite and famatinite nanomaterials with XPS, UPS, and EPR methods alongside a systematic analysis of dopant-dependent effects on the electronic structure and magnetic interactions for each material. XPS showed that the Cu and Sb species in tetrahedrite and famatinite possess different oxidation states, while UPS characterization reveals larger dopant-dependent shifts in the work function for tetrahedrite nanoparticles (4.21 to 4.79 eV) than for famatinite nanoparticles (4.57 to 4.77 eV). Finally, all famatinite nanoparticles display an EPR signal, indicating trace amounts of paramagnetic Cu(II) present below the detection limit of XPS. For tetrahedrite, EPR signatures were observed only for the Zn-doped and Mn-doped nanoparticles, suggesting signal broadening from Cu–Cu spin exchange or spin–lattice relaxation. This study demonstrates the complementary nature of XPS and EPR techniques for studying the oxidation states of metals in solid-state nanomaterials. Comparing the electronic and magnetic properties of tetrahedrite and famatinite while studying the impact of dopant incorporation will guide future endeavors in designing sustainable, high-performance materials for renewable energy applications.

To report the metabotropic glutamate receptor 5 (mGluR5) as the autoantigen of antibodies from 2 patients with Hodgkin lymphoma (HL) and limbic encephalopathy (Ophelia syndrome).

ABSTRACTEastern equine encephalitis virus (EEEV) is a highly virulent, mosquito-borne alphavirus that causes severe and often fatal neurological disease in humans and horses in eastern North American, the Caribbean, and Mexico and throughout Central and South America. EEEV infection is diagnosed serologically by anti-EEEV-specific IgM detection, with confirmation by the plaque reduction neutralization test (PRNT), which is highly specific for alphaviruses. Live virus is used in the PRNT procedure, which currently requires biosafety level 3 containment facilities and select agent security in the case of EEEV. These requirements restrict the ability of public health laboratories to conduct PRNTs. Sindbis virus (SINV)/EEEV recombinant constructs have been engineered to express the immunogenic structural proteins from 2 wild-type EEEV strains in an attenuated form. These SINV/EEEVs, which are not classified as select agents, were evaluated as alternative diagnostic reagents in a PRNT using human, equine, and murine sera. The results indicate that the chimeric viruses exhibit specificity comparable to that of wild-type EEEV, with only a slight reduction in sensitivity. Considering their benefits in increased safety and reduced regulatory requirements, these chimeric viruses should be highly useful in diagnostic laboratories throughout the Americas.

New SHRIMP U-Pb ages and geochemical data have been obtained for the volcano-sedimentary Loch Burn Formation (LBF). A rhyolitic clast from the tops of the Stuart Mountains gave a SHRIMP age of 150.3 ± 1.9 Ma, and a very fine sandstone from the same area was dominated by 147.9 ±2.1 Ma zircons. These ages imply a <148 Ma depositional age for the LBF in this area, in contrast to a previous 195-1+3Ma age determination for an intercalated felsic flow in the North Fiord area, c. 1 km distant. Two tonalitic clasts from Cumbrae Island gave ages of 354.6 ± 2.6 and 326.8 ±3.2 Ma, respectively. The c. 47 m.y. difference between depositional ages in the Stuart Mountains and North Fiord indicates that the LBF as currently mapped includes more than one unit. however, volcanic clasts and lavas from the two areas are indistinguishable in terms of major and trace element geochemistry, and there is currently insufficient information to discriminate between the two units. informal units are therefore proposed: the < 148 Ma LBF-2 unit and the c. 195 Ma LBF-1 unit. volcanic clasts and lavas from both units are probably derived from the Darran Suite arc. The c. 327 Ma tonalite clast has moderate Zr/TiO2 and chemistry similar to most of the other LBF tonalite samples, whereas the c. 355 Ma tonalitic clast has unusual, very high Zr chemistry. Neither appear to be related to any New Zealand plutonics currently well characterised in the literature, based on differences in major and trace element chemistry. however, recent work indicates that possible correlatives with appropriate age and geochemistry exist for both groups of tonalites. No Western Province material is recorded in any of the LBF samples, but this is not considered to exclude formation adjacent to or within the gondwana margin.

OBJECTIVE: To compare the different sterility standards and the cost issues involved when choosing an opioid product for intraspinal administration.DATA SOURCES: Literature accessed through MEDLINE and other Internet search engines (September 2002–April 2003) was evaluated. Key search terms included epidural/intrathecal, opioids, sterility, and compounding.DATA SYNTHESIS: Intraspinal use is prevalent in the area of pain management. Product selection is of utmost importance when administering through the intraspinal route. An evaluation of guidelines on sterility and a cost comparison were conducted.CONCLUSIONS: The preservative-free commercially available products that are indicated for intrathecal/epidural use are the best alternative due to proper outside testing and stringent quality assurance. The generic morphine preservative-free product may also be considered if proper steps are taken to ensure that the final product is diluted properly.

Despite extensive research, reduced corn (Zea maysL.) performance is still encountered using conservation tillage on fine‐textured soils in cool humid temperate climates. These problems are intensified when corn is planted into residue from a previous crop such as winter wheat (Triticum aestivumL.). The objective of this 4‐yr study was to determine the influence of fall zone tillage (ZT), no tillage (NT), and conventional moldboard plow tillage (CT) (fall plowing) on corn performance and soil physical quality under a winter wheat–corn–soybean (Glycine maxL. Merr.) rotation with and without red clover (Trifolium pratenseL.) (RC) underseeded in the wheat phase of the rotation. A randomized complete block design (3 × 2 factorial, 4 replicates) was established on three adjacent fields in the fall of 1996 on a Brookston clay loam soil (fine loamy, mixed, mesic, Typic Argiaquoll) at Woodslee, ON Canada, and measurements were collected during 1997 to 2000. Over both wet and dry growing seasons from 1998‐2000, zone tillage following underseeded RC produced average corn grain yields (7.23 Mg ha−1) that were within 1% of those obtained using conventional tillage (7.33 Mg ha−1), and 36% higher than those obtained using no tillage and RC (5.33 Mg ha−1). Zone tillage also improved soil quality as evidenced by generally lower soil strength than no tillage, and near‐surface soil physical quality parameters that were equivalent to, or more favorable than, those of the other treatments. It was concluded that corn production using zone tillage and RC underseeding is a viable option in Brookston clay loam soil, as it retains much of the soil quality benefit of conventional tillage but still achieves most of the yield benefit of conventional moldboard plow tillage.

The Late Cretaceous-Paleocene succession exposed on the Tora coast, near the southeastern tip of the North Island, is distinguished by an unusual lithofacies of the Whangai Formation, and by an apparently unique formation, Manurewa Formation, which spans the Cretaceous/Tertiary (K/T) boundary.The Late Cretaceous siliceous Whangai Formation at Tora includes zones of slumps and olistostromes, containing megaclasts of limestone up to 3 m long. The olistostromal deposits suggest steep submarine topography with a high rate of erosion, and imply tectonic activity. The common occurrence of hummocky cross-stratification suggests deposition in shelf depths above storm wave base. The sharply overlying Manurewa Formation is interpreted as the infill of a major shallow channel complex, perhaps >9 km wide and spanning the K/T boundary in time. The older of two channelled units is of latest Cretaceous (latest Haumurian/late Maastrichtian) age, and consists of bioturbated alternating thin sandstone and mudstone with thin conglomerate lenses and limestone beds. It is likely to have been deposited in a low-energy environment, probably deeper than that of the Whangai. The younger channel system, of early Paleocene (early Teurian) age, erodes into the older in the northeast, and into the underlying Whangai Formation in the southwest. Basal deposits consist predominantly of medium to coarse, thick-bedded, glauconitic sandstone, with local low-angle cross-stratification and microflora typical of low salinity conditions, suggesting deposition in shallow shelf depths. These deposits contain olistrostromes with megaclasts up to 1 m long of limestone and rarer dark grey siltstone or very fine sandstone clasts typical of Whangai Formation. The inclusion of megaclasts of Whangai Formation indicates that local emergence and erosion of older strata was occurring. Deposits grade upward into well-sorted bioturbated sandstones of the Awhea Formation, with prominent low-angle cross-stratification, interpreted as very shallow marine, probably nearshore deposits.The channel system represented by the Manurewa Formation records an initial relative sea-level rise, followed by an abrupt sea-level fall at, or close to, the K/T boundary. New Zealand was in a passive margin tectonic setting at the time, but the widespread presence of olistostromes, some including clasts derived from older strata, suggest that local tectonic activity and uplift was occurring. The effects may have been enhanced by a climatic shift in storm tracks and intensity in the latest Cretaceous, which is supported by the evidence of strong wave activity.By contrast, to the south in Marlborough, the K/T boundary succession is commonly characterised by an apparently conformable lithologic change from limestone to chert, although with local hiatus. To the north, in southern Hawke's Bay, the coeval succession is characterised by a disconformity separating greensand from underlying light grey, slightly calcareous mudstone of the Whangai Formation. The Tora sequence may provide the link between two distinctly different lithologic successions.

A series of 1,3,5-triazine-based estrogen receptor (ER) modulators that are modestly selective for the ERβ subtype are reported. Compound 1, which displayed modest potency and selectivity for ERβ vs ERα, was identified via high-throughput screening utilizing an ERβ SPA-based binding assay. Subsequent analogue preparation resulted in the identification of compounds such as 21 and 43 that display 25- to 30-fold selectivity for ERβ with potencies in the 10−30 nM range. These compounds profile as full antagonists at ERβ and weak partial agonists at ERα in a cell-based reporter gene assay. In addition, the X-ray crystal structure of compound 15 complexed with the ligand binding domain of ERβ has been solved and was utilized in the design of more conformationally restrained analogues such as 31 in an attempt to increase selectivity for the ERβ subtype.

AuCl4^- ions are transformed into Au crystallites via two consecutive photoreactions inside cross-linked polymers of diallyldimethylammonium chloride swollen with methanol. The photoreactions are markedly influenced by the gel matrix, which facilitates pathways not observed in homogeneous solutions and controls the direction of propagation. Initially, the reactions are repressed by air, but at longer times they are aided by products from the O2-reduction. The first process is an efficient monophotonic chain reduction of AuCl4^- with chain lengths in excess of 80 and an atypical pseudofirst-order termination. Kinetic data from fully swollen gels is understood in terms of a mechanism involving solution reactions of ·CH2OH radical chain carriers. Light-absorbing products of the first photoreaction, believed to be gold clusters, initiate the second process that yields metal particles. Several common kinetic features are displayed by both photoreactions. However, generation of Au crystallites takes place via an unusual biphotonic chain reaction, with reaction rates that are correlated to the number of particle formation and decay cycles.

The 0.23 Ma Kaingaroa Ignimbrite is a composite, multiple flow-unit ignimbrite erupted from the Reporoa Caldera, Taupo Volcanic Zone, New Zealand. Reporoa Caldera evolved from a single vent during the initial stages of the Kaingaroa eruption, to a trapdoor caldera with the opening up of fractures along the eastern margin and asymmetric eruption of early phases of the ignimbrite. Finally, plate collapse occurred during the later stages of the eruption. Kaingaroa Ignimbrite pumice clasts range in composition from dacite to rhyolite. Five pumice types have been identified based largely on the geochemical variation of Rb and Sr and ferromagnesian mineral composition. Pumice types A, B, C, and D exhibit variations in mineralogy, trace element chemistry, and isotopic composition consistent with derivation from a weakly zoned magma chamber. A subordinate dacitic juvenile component (type E) appears to be unrelated to the Kaingaroa pumices by crystal fraction-ation or assimilation, and is interpreted as a distinct magma batch that was incorporated into the eruption. The asymmetrical removal of magma from the chamber during caldera collapse is inferred to have resulted in a greater degree of drawdown along the eastern margin of the chamber, as suggested by the current spatial distribution of post-caldera rhyolites.

The objectives of the current experiment were to determine whether boars heterozygous for the mutation in skeletal ryanodine receptors (sRyR), known to cause porcine stress syndrome, differed from wild-type boars in hypothalamic-pituitary-adrenal axis (HPA) function. We have examined basal plasma ACTH, cortisol, and corticosteroid-binding globulin (CBG) concentrations; plasma ACTH and cortisol responses to a nose-snare stressor and at slaughter; dexamethasone suppression of plasma ACTH and cortisol concentrations; and glucocorticoid receptor (GR) density in the pituitary gland, hippocampus, hypothalamus, and frontal cortex. We have also examined carcass yields, composition, and meat quality to determine whether differences in HPA activity were accompanied by an increased incidence of meat quality characteristics associated with pale, soft, exudative (PSE) meat. Thirty boars either heterozygous or wild-type (n = 15 per genotype) for mutated sRyRwere tested for HPA function at 7 mo of age. Heterozygous boars had lower basal plasma ACTH (P< .05) and cortisol (P< .04) concentrations. Integrated basal plasma ACTH and cortisol levels were also lower (P< .05 and P< .005, respectively). Genotype had no significant effect on basal CBG, stressor-induced (nose snare or slaughter) or dexamethasone suppression of plasma ACTH or cortisol concentrations. No differences in immunoreactive GR levels were found in the pituitary gland or any brain region examined. We did find a significant, negative correlation (r = −.62, P< .02) between peak (0800) basal plasma ACTH concentrations and hippocampal GR levels. The alterations in basal HPA function in heterozygous boars were accompanied by lighter body weights (P< .03), decreased carcass fat depth (P< .04), and increased carcass lean yields (P< .02). There was a higher incidence of meat quality characteristics associated with PSE meat in heterozygous boars indicated by higher carcass temperatures (P< .04) and meat brightness (P< .0001) with lower carcass pH at slaughter (P< .03) and after chilling (P< .003). In conclusion, we have found differences in basal and not stressor-induced HPA function between boars heterozygous and wild-type for mutated sRyR. This altered basal HPA activity was accompanied by an increased incidence of meat quality aspects associated with PSE meat in heterozygous boars.

AbstractStocking rate is the key, determining effect of management intensive grazing on dairy farm profitability. However, increased stocking rate can increase NO3leaching from pastures. Increasing stocking rate increases NO3- loss through leaching because the bulk of the N conszdmed by the anilmal is excreted in concentrated areas of the pasture mainly in urine. We used experimental data from the northeast U.S. and the literature to assess the relationships between stocking rate and NO3leaching losses beneath an intensively grazed pasture. A relatively low cumulative seasonal stocking rate of about 200 mature Hothead ha−1could result in a 10 mg l−1NO3N concentration in the leachate beneath a fertilized, intensively grazed pasture. This means that while management intensive grazing can improve farm profitability and help control erosion, it can have a significant negative effect on water quality beneath pastures. The extent to which this effect occurs within specific watershed need to be evaluated in context of the other cropping systems and lands uses within the watershed.

Endemic/epidemic dengue viruses (DEN) that are transmitted among humans by the mosquito vectors Aedes aegypti and Aedes albopictus are hypothesized to have evolved from sylvatic DEN strains that are transmitted among nonhuman primates in West Africa and Malaysia by other Aedes mosquitoes. We tested this hypothesis with phylogenetic studies using envelope protein gene sequences of both endemic/epidemic and sylvatic strains. The basal position of sylvatic lineages of DEN-1, -2, and -4 suggested that the endemic/epidemic lineages of these three DEN serotypes evolved independently from sylvatic progenitors. Time estimates for evolution of the endemic/epidemic forms ranged from 100 to 1,500 years ago, and the evolution of endemic/epidemic forms represents relatively recent events in the history of DEN evolution. Analysis of envelope protein amino acid changes predicted to have accompanied endemic/epidemic emergence suggested a role for domain III in adaptation to new mosquito and/or human hosts.

The 0.89 Ma Tikorangi Ignimbrite (revised name) is a mixed andesite-rhyolite ignimbrite preserved within a localised area of the Matahana Basin on the western side of the Taupo Volcanic Zone, New Zealand. The source of the ignimbrite is poorly constrained, but the location and limited maximum pumice and lithic data available suggest that the ignimbrite was emplaced by a pyroclastic flow erupted from within the Kapenga caldera complex. The ignimbrite is the oldest exposed unit sourced from the complex and offers a window into the early history of the Taupo Volcanic Zone.The Tikorangi Ignimbrite can be conveniently divided into three units. The Lower Tikorangi ignimbrite (LTi) is dominantly rhyolitic and has been subject to varying degrees of hydrothermal alteration. This progressively grades into the Middle Tikorangi ignimbrite (MTi), which best illustrates the mixed nature of the ignimbrite, and has four types of juvenile pumice: black, grey black, brown black (all andesitic, in various states of oxidation), and white-grey (rhyolitic). The top of the Middle Tikorangi ignimbrite grades up into a densely welded, dominantly andesitic lenticulite. The Upper Tikorangi ignimbrite (UTi) is poor in lithics, crystals, and pumice, but with both andesite and rhyolite pumice clasts common up to the top of the ignimbrite.The geochemistry and petrography of vitric fragments and fiamme indicate that both magma mixing and mingling between andesite and rhyolite have occurred. Mixing occurred when hotter andesite magma was injected into a reservoir of more viscous rhyolitic magma and immediately triggered a violent eruption. The initial stage of the eruption was driven by superheating of the rhyolite magma and continued degassing. Subsequently, chamber evacuation permitted caldera block collapse that drove the eruption by pumping out the remaining magma. An increase in rifting within the Taupo Volcanic Zone, at 0.90 Ma, may have facilitated the eruption process.

Summary A 1983 human Mississippi isolate of eastern equine encephalomyelitis virus (EEEV), recently identified as an antigenic subtype of the North American variety, was genetically characterized using oligonucleotide fingerprinting and sequencing of viral RNA. This strain was found to be very closely related to other North American EEEV isolates from the same time period. Phylogenetic analysis suggested that this subtype belongs to a single EEEV lineage in North America. Two amino acid substitutions in the E 2 envelope glycoprotein, not seen in eight other isolates sequenced, probably contributed to the antigenic difference with respect to other EEEV strains. These substitutions include threonine for lysine at position 71, resulting in the addition of a potential N-linked glycosylation site, and lysine for glutamic acid at position 147.

Twelve stutterers and twelve non-stutterers each read out loud following three types of rehearsal: overt rehearsal of the material, silent rehearsal, or inappropriate overt rehearsal (counting backwards). Silent rehearsal impaired performance (fluency) compared to the other conditions. Heart rate measures (HR) and electro-myography (EMG) did not differentiate stutterers from non-stutterers, except that EMG immediately before speech was significantly elevated after silent rehearsal for stutterers. the data suggest that silent rehearsal may be accompanied by excessively high muscle tone, and impair rather than facilitate fluency.

Western equine encephalomyelitis (WEE) virus (Togaviridae: Alphavirus) was shown previously to have arisen by recombination between eastern equine encephalomyelitis (EEE)- and Sindbis-like viruses (C. S. Hahn, S. Lustig, E. G. Strauss, and J. H. Strauss, Proc. Natl. Acad. Sci. USA 85:5997-6001, 1988). We have now examined the recombinational history and evolution of all viruses belonging to the WEE antigenic complex, including the Buggy Creek, Fort Morgan, Highlands J, Sindbis, Babanki, Ockelbo, Kyzylagach, Whataroa, and Aura viruses, using nucleotide sequences derived from representative strains. Two regions of the genome were examined: sequences of 477 nucleotides from the C terminus of the E1 envelope glycoprotein gene which in WEE virus was derived from the Sindbis-like virus parent, and 517 nucleotide sequences at the C terminus of the nsP4 gene which in WEE virus was derived from the EEE-like virus parent. Trees based on the E1 region indicated that all members of the WEE virus complex comprise a monophyletic group. Most closely related to WEE viruses are other New World members of the complex: the Highlands J, Buggy Creek, and Fort Morgan viruses. More distantly related WEE complex viruses included the Old World Sindbis, Babanki, Ockelbo, Kyzylagach, and Whataroa viruses, as well as the New World Aura virus. Detailed analyses of 38 strains of WEE virus revealed at least 4 major lineages; two were represented by isolates from Argentina, one was from Brazil, and a fourth contained isolates from many locations in South and North America as well as Cuba. Trees based on the nsP4 gene indicated that all New World WEE complex viruses except Aura virus are recombinants derived from EEE- and Sindbis-like virus ancestors. In contrast, the Old World members of the WEE complex, as well as Aura virus, did not appear to have recombinant genomes. Using an evolutionary rate estimate (2.8 x 10(-4) substitutions per nucleotide per year) obtained from E1-3' sequences of WEE viruses, we estimated that the recombination event occurred in the New World 1,300 to 1,900 years ago. This suggests that the alphaviruses originated in the New World a few thousand years ago.

Continuous, persistent replication of a wild-type strain of vesicular stomatitis virus in cultured sandfly cells for 10 months profoundly decreased virus replicative fitness in mammalian cells and greatly increased fitness in sandfly cells. After persistent infection of sandfly cells, fitness was over 2,000,000-fold greater than that in mammalian cells, indicating extreme selective differences in the environmental conditions provided by insect and mammalian cells. The sandfly-adapted virus also showed extremely low fitness in mouse brain cells (comparable to that in mammalian cell cultures). It also showed an attenuated phenotype, requiring a nearly millionfold higher intracranial dose than that of its parent clone to kill mice. A single passage of this adapted virus in BHK-21 cells at 37 degrees C restored fitness to near neutrality and also restored mouse neurovirulence. These results clearly illustrate the enormous capacity of RNA viruses to adapt to changing selective environments.

The Early Cretaceous Darran Complex of the Median Tectonic Zone near Milford, South Island, New Zealand, consists dominantly of biotite - two-pyroxene diorites cut by biotite-hornblende microdiorite and quartz monzodiorite dikes. The host diorite gives a 138 ± 2.9 Ma SHRIMP age on zircons, which is interpreted to be the age of igneous crystallisation. The calc-alkaline geochemistry of the host diorites and the microdiorites is attributed to melting of a mantle wedge source fluxed by slab-derived fluids. Ductile deformation (D1) of the host diorite and the microdiorite dikes took place at mid-upper amphibolite facies conditions, with extension lineations indicating a top to the NNE sense of shear. A SHRIMP age of 136 ± 1.9 Ma on zircons from a quartz monzodiorite dike injected along D1 shears is statistically indistinguishable from that of the host diorite. This suggests that D1 was synmagmatic and that subduction, during or shortly after magma emplacement, was oblique to the Gondwana margin at c. 138 Ma.The quartz monzodiorite dikes are enriched in Na2O, Al2O3, and Sr, depleted in Y, and have a distinctly adakitic geochemistry. The change in chemistry from calc-alkaline magmas to alkali-calcic adakitic magmas reflects the melting of a mafic, garnet-bearing, essentially plagioclase-free source in the root of a volcanic arc system.

Ion microprobe U-Pb zircon ages have been obtained from four samples of Cretaceous granitoid and two samples of volcanogenic sediment from the northwest Nelson-Westland region of the South Island of New Zealand. Crow Granite, which intrudes lower Paleozoic metasedi-mentary rocks in the Buller Terrane on the eastern side of the Karamea Batholith, has given a crystallisation age of 137 ± 3 Ma (2a). This age is typical of the Jurassic-Early Cretaceous plutonic rocks that dominate the Median Tectonic Zone, and raises the possibility that the Western Province and the Median Tectonic Zone were linked some 20 m.y. earlier than previously proposed. The “Gouland granod-iorite”, which forms a large pluton at the northeastern margin of the Karamea Batholith, has a crystallisation age of 119 ± 2 Ma (2a). This age is similar to the Separation Point Batholith (118 Ma), and the distinctive chemistry of the batholith (high Na, Al, Sr, and low Y) is also displayed by the Gouland granodiorite. The “Big Deep granite”, which intrudes Devonian granites of the Karamea Batholith in the Upper Buller Gorge, has a crystallisation age of 110 ± 3 Ma (2a), similar to the age of Buckland Granite (Rahu Suite) in the Paparoa Batholith. Berlins Porphyry in the Lower Buller Gorge also has a mid-Cretaceous age of 111 ± 2 Ma (2a). Two samples of Stitts Tuff from the Lower Buller Gorge have given crystallisation ages of 101 ± 2 Ma (2a) and 102 ± 3 Ma (2a). These ages constrain the timing of initiation of fault-bounded sedimentary basins on the West Coast, related to a major period of crustal extension before the opening of the Tasman Sea Basin.

The performance of respirator cartridges was measured during challenge by organic-vapor mixtures. All cartridges were tested in pairs under carefully controlled conditions of mass flow, temperature and relative humidity. Five chemical compounds were used during the testing: methyl ethyl ketone, isopropyl alcohol, hexane, n-butyl acetate and ethyl benzene. Cartridges were challenged by a single compound first at 1000 and then at 2000 ppm (by volume) concentration, under a standard flow of 40 Lpm. Every challenge was performed separately at 50% and then at 85% relative humidity. The authors chose the high concentration of each single-component challenge to equal the arithmetic total concentration of the five different two-component mixtures that were subsequently tested. The chemical concentrations were monitored upstream of the cartridges by infrared analysis and downstream by gas chromatography. The results showed that the observed breakthrough times for most of the mixture components were similar to those times measured for each single component at its high concentration.

Light intensity and color preferences of five ascoglossan (= sacoglossan) molluscs were analyzed, including three chloroplast symbiotic species (Costasiella lilianae (Marcus), Tridachia crispala (Morch), and Elysia tuca (Marcus), and two aposymbiotic species (Oxynoe antillarum Morch and Berthelinia caribbea Edmunds). Symbiotic species oriented toward light, but preferred intensities less than those of photosynthetic optima. Aposymbiotic species avoided light at all intensities tested (100-500 με/m2/s). Light avoidance, and selection of intensities sub-optimal for photosynthesis, possibly function as mechanisms for predator avoidance. Field observations showed that most species exhibit a diurnal cycle of movements (upward at night, and seeking concealment by day); this pattern presumably results from the light intensity selection behavior.All species except Oxynoe antillarum exhibited distinct color preferences. These may function in location of food or, less likely, serve as temporal cues regulating vertical movements.

Secular trends in blood pressure among young adults reflect the proportion of the population at risk of developing hypertension and may be markers of progress in primary prevention. National health examination data from three successive surveys were analyzed to assess blood pressure trends for adult blacks and whites aged 18-34 years in two body mass index (BMI; weight (kg)/height (m)2) strata (< 25 or > or = 25). Blood pressure was categorized into a four-point ordinal scale using the weighted, within-sex 50th, 75th, and 90th percentiles for 18- to 24-year-old adults in the 1960-1962 survey. The effects were analyzed with cumulative logit models with alpha = 0.01. The systolic blood pressure decreased moderately for 25- to 34-year-old males and for females except those aged 25-34 years with a BMI of > or = 25. Diastolic blood pressure increased among males with a BMI of > or = 25 and among white males with a BMI of < 25, but did not show a significant overall trend among females. A BMI of > or = 25 was associated with substantially higher blood pressure in each survey, except for one age-sex-race subgroup. Racial differences within BMI were less consistent than the differences across BMI strata. In summary, the situation with respect to hypertension among females may have improved during this time period but for males may have worsened with respect to diastolic blood pressure. Data for both sexes support a need for population-wide obesity prevention to reduce the incidence of hypertension.

One of the most important questions in arbovirology concerns the origin of epidemic Venezuelan equine encephalitis (VEE) viruses; these viruses caused periodic, extensive epidemics/epizootics in the Americas from 1938-1973 (reaching the United States in 1971) but had recently been presumed extinct. We have documented the 1992 emergence of a new epidemic/epizootic VEE virus in Venezuela. Phylogenetic analysis of strains isolated during two outbreaks indicated that the new epidemic/epizootic virus(es) evolved recently from an enzootic VEE virus in northern South America. These results suggest continued emergence of epizootic VEE viruses; surveillance of enzootic viruses and routine vaccination of equines should therefore be resumed.

Management intensive grazing (MIG) is a grazing system in which animals at a high stocking density are rotated through several paddocks at short time intervals (12–24 h) so that animal performance is maximized. Although MIG has the potential to increase dairy farm profitability in the northeast USA, recent work in this region has shown that a substantial amount of N recycled through urine is leached below the root zone. How soil properties, particularly water‐holding capacity, can affect NO3‐N leaching from beneath urine and feces spots under the climatic conditions of the northeast USA is not known. We conducted a field study to measure NO3‐N leaching loss from spring‐, summer‐, and fall‐applied urine and summer applied feces beneath N‐fertilized orchardgrass (Dactyls glomerataL., cv. Pennlate) using large drainage lysimeters installed in two soils that differed greatly in soil water storage capacity. The study sites were located in central Pennsylvania on a Hagerstown silt loam soil (fine, mixed, mesic Typic Hapludalf) and a Hartleton channery silt loam (loamy‐skeletal, mixed, mesic Typic Hapludult). Compared to the Hagerstown soil, the Hartleton soil provided an 85% decrease in plant N uptake, a 52% increase in leachate volume, but no significant increase in NO3‐N leaching beneath urine spots. However, the lower soil water‐holding capacity of the Hartleton soil caused the NO3‐N leaching losses to be more evenly distributed over the year.

There is a pressing need for a social dimension to be built into environmental planning and management programmes in the Pacific, due to the fact that conservation occurs within the context of a social and cultural world, and that many environmental management failures are underwritten by social problems. The political strength of the environment sector in Fiji will determine the degree of central government support for environmental dimensions of national planning. Such strengthening can be facilitated through improving the social context of the practice of environmental management and planning. A social dimension is built into an environmental planning model which incorporates social as well as biological criteria for the selection of ecologically sensitive areas in need of environmental protection.

Abstract: Emuruangogolak is a Quaternary basalitrachyte volcano situated in the Suguta graben of the northern Kenva rift, and probably erupted last early in this century. Following the construction of an early trachytic shield volcano, two episodes of caldera collapse occurred. each preceded by explosive pvroclastic activity. Post-calelera volcanism consisted of alternating phases of basalt and trachyte eruption. The basic lavas are high-Ti ferrobasalts of a mildly alkaline ‘transitional’ composition and the trachytes are peralkaline and oversaturated. A distinct compositional bimodality exists and no rocks in the range 49–59. SiO, have been found. Major and trace element analyses suggest that the trachytes are genetically related to the basalts. Associations of almost identical lavas occur in Ethiopia. Pantelleria and the Azores but with the presence of intermediate terms Fractional crystallization is the mechanism currently preferred to account for the origin of the trachytes. The ‘Daly gap’ may be a consequence of a crystallization process which limits the volume of intermediate magma available at any time. In addition, the physical properties and spatial distribution of the different magmas probably discriminate against the cruption of lavas of intermediate composition.

Abstract: Seven Pliocene volcanoes, one of which is described in detail, occur in the northern part of the Kenya Rift. They have low-angle, shield like forms, and comprise lavas, pumice tuffs and ash-flow tuffs almost wholly of trachytic composition. Each volcano possesses a structurally complex source zone in which plugs, dykes and pumice tuffs are concentrated and in which clearly defined craters and calderas are uncommon. By contrast, the flank zones are stratiform with slopes of about 5 and are composed of lavas and ash-flow sheets erupted in a highly fluid condition. The volcanoes range up to 50 km in diameter and are elongated parallel to the general trend of the rift reflecting a tectonic control on the distribution of the vents and their products. This combination of morphological, structural and compositional features suggests that the volcanoes are of a type not described before. Notes on the petrography of the lavas are included and it is suggested that the trachytes are petrogenetically related to alkali basalts, compositionally similar to those which form the substrate to the trachyte volcanoes.

Semen donors have been required to register with the Human Fertilization and Embryology Authority since its formation in 1990. Since then many clinics have reported a shortage of donor semen for donor insemination treatment. Is this because potential donors are worried about the protection of their anonymity? No published studies are available concerning the attitudes to semen donation in the UK. It was against this background that an investigation of the attitudes of potential semen donors was carried out. Four dimensions were investigated: (i) motives, (ii) personal detachment and involvement, (iii) detachment and involvement with respect to recipients, and (iv) detachment and involvement with respect to offspring. A total of 55 potential semen donors completed the attitude questionnaire from semen donation programmes in three in-vitro fertilization units. The questionnaire format was found to be an effective method of data collection for this sensitive area of research, and the major findings were (i) 89% of potential donors required confidentiality and guaranteed anonymity; (ii) 82% did not mind providing non-identifying information to the recipients and offspring; (iii) 69% of potential donors expected financial reward; and (iv) 69% did not welcome counselling.