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Changes in vegetation in North America indicate Holocene shifts in the latitudinal temperature gradient along the western margin of the North Atlantic. The dynamics of tree taxa such as oak (Quercus) and hickory (Carya) showed opposing directions of change across different latitudes, consistent with changes in temperature gradients. Pollen-inferred temperatures from 34 sites quantify the changes and reconstruct a long-term southward shift of the sharpest temperature gradient in winter and a northward shift in summer. During the mid-Holocene, however, an oscillation in tree distributions interrupted the trends indicating that the steepest portion of the seasonal temperature gradients migrated rapidly northward at 5.8-3.2 ka. The shift produced an unusually late summer thermal maxima at 42-43.5°N where oak abundance peaked both in the early and mid-Holocene. The changes appear consistent with orbital and ice sheet forcing as well as millennial variability in the North Atlantic pressure field during the mid-Holocene.

A multiproxy record from Twin Ponds, VT, is used to reconstruct climatic variability during the late Pleistocene to early Holocene transition. Pollen, ostracodes, δ18O, and lithologic records from 13.5 to 9.0 cal ka BP are presented. Pollen- and ostracode-inferred climatic reconstructions are based on individual species’ environmental preferences and the modern analog technique. Principal components analysis of all proxies highlights the overall warming trend and centennial-scale climatic variability. During the Younger Dryas cooling event (YD), multiple proxies show evidence for cold winter conditions and increasing seasonality after 12.5 cal ka BP. The early Holocene shows an initial phase of rapid warming with a brief cold interval at 11.5 cal ka BP, followed by a more gradual warming; a cool, wet period from 11.2 to 10.8 cal ka BP; and cool, dry conditions from 10.8 to 10.2 cal ka BP. The record ends with steady warming and increasing moisture. Post-YD climatic variability has been observed at other sites in the northeastern United States and points to continued instability in the North Atlantic during the final phases of deglaciation.

Regions with a large percentage of precipitation occurring near freezing experience high percentages (>10%) of misclassified precipitation events (rain versus snow) and necessitate efforts to improve precipitation phase determination schemes through the use of more accurate surface air temperature thresholds (Trs). Meteorological data from 169 sites in Scandinavia were used to test the applicability of using physiographic categories to determine Trs. Three classification methods involving varying degrees of automation were evaluated. The two automated methods tested did not perform as well as when tested on a smaller region, showing only 0.16% and 0.20% reduction in error. A semi-manual method produced the largest average reduction in misclassified precipitation (0.53%) across all sites. Further refinement of classification criteria for mountain and hill stations showed that at mesoscales (>5 km), maximum elevation is a better predictor of Trs (0.89% average reduction in error) than terrain relief (0.22%), but that relief becomes increasingly important at microscales (0.90%). A new method for categorizing mountainous stations based on upslope or downslope air movement increased the average reduction in error up to 0.53%. These results provide a framework for future landscape classification methods and confirm the importance of microscale topography for determining Trs in alpine regions.

We extend a published 9000 yr fire history record from Little Lake, in the Oregon Coast Range, to 35,000 yr and compare it with the established pollen record from the site. The fire history is based on a high-resolution analysis of charcoal preserved in lake sediments, providing a fire history record that spans the Last Glacial Maximum in North America. The data enabled us to address questions regarding the interactions between large-scale climate changes associated with the shift from glacial to interglacial conditions and the accompanying changes in forest vegetation and fire regimes. The vegetation history indicates a change from open subalpine forests to closed western hemlock and Douglas fir forests as climate moved from cold and dry full glacial to warm and wet Holocene conditions. The fire history indicates that although there was more biomass burned in the Holocene, the frequency of fires between glacial and interglacial conditions was not significantly different, and the fire frequency did not change in concert with regional shifts in vegetation. This suggests that fire is a product of seasonal or multiyear variations in climate that may not cause significant shifts in vegetation. Also, as this short-term climate variability becomes more common in the near future, conditions for fires in these mesic forests may become more common as well.

Background and Aims Old vineyards are often suggested to be superior to younger ones, a claim that has scarcely been investigated scientifically. The aim of this study was to investigate if vineyard age influences vine performance. Methods and Results Five commercial Shiraz vineyards in the Barossa Valley, SA, were selected; each site contained younger vines, which had been vegetatively propagated from older vines on the same site. Measurements of vegetative growth and reproductive development were obtained over three seasons. Results show that the effect of vine age is difficult to measure and separate from seasonal and site interactions. Vine age was strongly correlated with trunk circumference. Vines aged 49 years showed more similarities with older vines (93–168 years old) than with younger vines (6–28 years old). Conclusions Vine age had an impact on grapevine reproductive performance. Older vines produced a yield greater than that of younger vines. Greater vine size, measured by increase in trunk circumference over time, may be a key determining factor in increased reproductive capacity. Significance of the Study Vine age is commonly attributed to superior vine performance, as a precursor to fruit and wine quality. Our findings suggest that increasing vine age had a positive effect on reproductive performance in terms of yield, contrary to popular belief. This establishes a starting point for future studies that are underway to quantify if these findings have an effect on fruit and wine composition and sensory attributes.

Landscape air temperature thresholds (TA) and percent misclassified precipitation (error) for 12 years of meteorological observations from 40 stations across the Scandinavian Peninsula were derived and compared using both manual and geographic information system (GIS) landscape classification methods. Dew-point, wet-bulb, and wet bulb 0.5 were also tested. Both classification methods used the following west to east landscape categories: windward (WW) ocean, coast, fjord, hill, and mountain in Norway; and leeward (LW) mountain, hill, rolling terrain, and coast in Sweden. GIS landscape classification has the advantages of automating the classification process and increasing objectivity. The GIS classification was based on station location (LW or WW) relative to the Scandinavian mountain range, and the % water or range of elevation change within 15 km. The GIS and manual method had the same TA for 20 stations, and similar total reduction in error (2.29 to 2.17% respectively) when compared to country TA. Therefore, automated GIS landscape classification can be used to decrease error from common country or global scale TA. Wet-bulb temperature thresholds for GIS landscapes resulted in a greater reduction in error (8.26%) compared to air (2.29%), and dew-point (−16.67%) thresholds. However, finding stations reporting relative humidity or wet-bulb temperature may limit its widespread use.

We present a new oxygen isotope (δ18O) record from carbonate-rich lake sediments from central Vermont. The record from Twin Ponds spans from 13.5 cal ka BP (1950 AD) to present, but contains a 6 ka long hiatus starting shortly after 7.5 cal ka BP. We compare the record for ca. 13.5–7.5 cal ka BP with published δ18O data from the region after using a Bayesian approach to produce many possible chronologies for each site. Principal component analysis then identified chronologically-robust, multi-site oxygen isotope signals, including negative values during the Younger Dryas, but no significant deviations from the early Holocene mean of the regional records. However, differences among sites indicate significant trends that likely relate to interacting changes in the regional gradients of seasonal temperatures and precipitation as well as moisture sources, moisture pathways, and aridity that were controlled by large-scale climatic controls such as insolation, the progressive decline of the Laurentide Ice Sheet, and changes in oceanic circulation. Centennial shifts punctuate these trends at ca. 9.3 and 8.2 cal ka BP, and reveal that the local character of these short-lived features requires a detailed understanding of lake hydrology and regional isotopic gradients to yield reliable information for regional climate reconstructions.

Pre-weaning lamb growth rates have dramatically increased on the hill country property Tempello, from 258 g/head/day in 2001 to 350 g/head/day in 2007. Total kilograms of lamb liveweight weaned off the Corriedale and Corriedale/Poll Dorset flock area has increased from 60 tonnes to 76 tonnes, despite a reduction in ewe numbers. Keywords: grazing management, hill country, lamb production, subterranean clover, summer dry

An ion of m/z 110.06036 (ion formula [C6H8NO](+); error: 0.32 mDa) was observed in the collision induced dissociation tandem mass spectrometry experiments of protonated N-(3-aminophenyl)benzamide, which is a rearrangement product ion purportedly through nitrogen-oxygen (N-O) exchange. The N-O exchange rearrangement was confirmed by the MS/MS spectrum of protonated N-(3-aminophenyl)-O (18) -benzamide, where the rearranged ion, [C6H8NO (18) ](+) of m/z 112 was available because of the presence of O (18) . Theoretical calculations using Density Functional Theory (DFT) at B3LYP/6-31 g(d) level suggest that an ion-neutral complex containing a water molecule and a nitrilium ion was formed via a transition state (TS-1), followed by the water molecule migrating to the anilide ring, eventually leading to the formation of the rearranged ion of m/z 110. The rearrangement can be generalized to other protonated amide compounds with electron-donating groups at the meta position, such as, -OH, -CH3, -OCH3, -NH(CH3)2, -NH-Ph, and -NHCOCH3, all of which show the corresponding rearranged ions in MS/MS spectra. However, the protonated amide compounds containing electron-withdrawing groups, including -Cl, -Br, -CN, -NO2, and -CF3, at the meta position did not display this type of rearrangement during dissociation. Additionally, effects of various acyl groups on the rearrangement were investigated. It was found that the rearrangement can be enhanced by substitution on the ring of the benzoyl with electron-withdrawing groups.

In South Asia, the technological and societal shift from drinking surface water to groundwater has resulted in a great reduction of acute diseases due to water borne pathogens. However, arsenic and other naturally occurring inorganic toxic substances present in groundwater in the region have been linked to a variety of chronic diseases, including cancers, heart disease, and neurological problems. Due to the highly specific symptoms of chronic arsenic poisoning, arsenic was the first inorganic toxic substance to be noticed at unsafe levels in the groundwater of West Bengal, India and Bangladesh. Subsequently, other inorganic toxic substances, including manganese, uranium, and fluoride have been found at unsafe levels in groundwater in South Asia. While numerous drinking water wells throughout Myanmar have been tested for arsenic, relatively little is known about the concentrations of other inorganic toxic substances in Myanmar groundwater. In this study, we analyzed samples from 18 drinking water wells (12 in Myingyan City and 6 in nearby Tha Pyay Thar Village) and 2 locations in the Ayeyarwaddy River for arsenic, boron, barium, beryllium, cadmium, cobalt, chromium, copper, fluoride, iron, mercury, manganese, molybdenum, nickel, lead, antimony, selenium, thallium, uranium, vanadium, and zinc. Concentrations of arsenic, manganese, fluoride, iron, or uranium exceeded health-based reference values in most wells. In addition, any given well usually contained more than one toxic substance at unsafe concentrations. While water testing and well sharing could reduce health risks, none of the wells sampled provide water that is entirely safe with respect to inorganic toxic substances. It is imperative that users of these wells, and users of other wells that have not been tested for multiple inorganic toxic substances throughout the region, be informed of the need for drinking water testing and the health consequences of drinking water contaminated with inorganic toxic substances.

A high-resolution pollen record from Fargher Lake, Washington shows a series of millennial-scale changes in vegetation and climate during marine isotope stages (MIS) 3 and 2. A comparison of Fargher Lake with pollen records from Little Lake, Oregon and Carp Lake, Washington, reveals regional patterns of change. During the early part of MIS 3 (ca 60,000–45,000 cal yr BP), Fargher and Carp lakes indicate transitions between open and closed vegetation and cold dry and warm wet conditions. Between 45,000 and 27,500 cal yr BP, all three records show shifts between low- and high-elevation taxa that indicate a series of temperature changes. These temperature changes are similar to those in the Santa Barbara Basin and may be explained by changes in the strength of the Aleutian low. During MIS 2 (27,500–14,000 cal yr BP), shifts between wet- and dry-adapted taxa were most prominent at Little Lake. There is also evidence for two minor warmings. MIS 2 climate variations do not correlate well with those in the Santa Barbara Basin. However, precipitation changes in the Pacific Northwest during MIS 2 correlate with evidence of ice-sheet surges into the North Atlantic and were probably related to variations in the strength and position of the glacial anticyclone and the jet stream.

Pollen and geochemical data from Little Lake, western Oregon, suggest several patterns of millennial-scale environmental change during marine isotope stage (MIS) 2 (14,100–27,600 cal yr B.P.) and the latter part of MIS 3 (27,600–42,500 cal yr B.P.). During MIS 3, a series of transitions between warm- and cold-adapted taxa indicate that temperatures oscillated by ca. 2°–4°C every 1000–3000 yr. Highs and lows in summer insolation during MIS 3 are generally associated with the warmest and coldest intervals. Warm periods at Little Lake correlate with warm sea-surface temperatures in the Santa Barbara Basin. Changes in the strength of the subtropical high and the jet stream may account for synchronous changes at the two sites. During MIS 2, shifts between mesic and xeric subalpine forests suggest changes in precipitation every 1000–3000 yr. Increases in Tsuga heterophylla pollen at 25,000 and 22,000 cal yr B.P. imply brief warmings. Minimum summer insolation and maximum global ice-volumes during MIS 2 correspond to cold and dry conditions. Fluctuations in precipitation at Little Lake do not correlate with changes in the Santa Barbara Basin and may be explained by variations in the strength of the glacial anticyclone and the position of the jet stream.

Four new species of Smittium (Zygomyco- ta, Trichomycetes, Harpellales), S. caudatum, S. com- mune, S. acutum, and S. kansense, that live in the hindguts of stream Chironomidae (midge) larvae collected in Kansas and Oklahoma are described. One or more axenic cultures were obtained from all species but S. kansense. Each of the cultured species has distinctive isozyme patterns, though 12 isolates of S. commune were split into two isozyme groups. Prob- lems in identification of Smittium spp. based solely on axenic cultures of the fungus are discussed.

Pollen records from two sites in western Oregon provide information on late-glacial variations in vegetation and climate and on the extent and character of Younger Dryas cooling in the Pacific Northwest. A subalpine forest was present at Little Lake, central Coast Range, between 15,700 and 14,850 cal yr B.P. A warm period between 14,850 and 14,500 cal yr B.P. is suggested by an increase in Pseudotsuga pollen and charcoal. The recurrence of subalpine forest at 14,500 cal yr B.P. implies a return to cool conditions. Another warming trend is evidenced by the reestablishment of Pseudotsuga forest at 14,250 cal yr B.P. Increased haploxylon Pinus pollen between 12,400 and 11,000 cal yr B.P. indicates cooler winters than before. After 11,000 cal yr B.P. warm dry conditions are implied by the expansion of Pseudotsuga. A subalpine parkland occupied Gordon Lake, western Cascade Range, until 14,500 cal yr B.P., when it was replaced during a warming trend by a montane forest. A rise in Pinuspollen from 12,800 to 11,000 cal yr B.P. suggests increased summer aridity. Pseudotsuga dominated the vegetation after 11,000 cal yr B.P. Other records from the Pacific Northwest show an expansion of Pinus from ca. 13,000 to 11,000 cal yr B.P. This expansion may be a response either to submillennial climate changes of Younger Dryas age or to millennial-scale climatic variations.

Trichomycetes (Zygomycota) are arthro- pod-associated fungi consisting of three orders, only one of which, the Harpellales, contains cultured spe? cies. Isozyme patterns were studied using starch gel electrophoresis of 108 isolates representing 18 de? scribed species from six genera of Harpellales (Cap- niomyces, Furculomyces, Genistelloides, Simuliomyces, Smittium, and Trichozygospora), and some unde? scribed species of Smittium, as well as three isolates of Amoebidium parasiticum (Amoebidiales) and three species of nontrichomycetous fungi. A total of 176 different band positions for 13 loci in 11 enzyme sys? tems were produced. The banding patterns were con? sistent with haploidy. Numerical taxonomic and prin- cipal coordinate analyses of Trichomycetes compared isozyme variation within and among described and undescribed species, including three named isolates of uncertain identity. There was no discernible pat? tern among the cultures attributable to geographic origin or type of insect host family. Isolates of de? scribed species produced similarity clusters that gen? erally correlated well with morphologically defined genera and species. Based on isozyme patterns, one isolate tentatively identified as G. hibernus was re-ex- amined and reclassified as C. stellatus. Thirty-six un? described isolates of Smittium produced seven clus? ters that probably represent new species. Other un? described Smittium isolates grouped with described species and may be conspecific. Cophenetic correla? tion coefficients for 13 clusters of Harpellales species were >0.90, but for A. parasiticum it was only 0.87; the latter may represent a species complex. Thirty- two isolates of Sm. culisetae originating from France, Australia, Japan, and six USA states (including Ha? waii) were isozymically very similar or identical to each other, despite differences in their geographic origins and dipteran host families. A phenogram based on isozyme patterns generally corresponded with one from a previous immunological study.

A new optical‐lever based atomic force microscope is described in which the cantilever scans and is accurately tracked by a scanning focused spot. It can operate at forces below one nanoNewton over image areas greater than 100 μ×100 μ. It can be combined with optical microscopes of high numerical aperture and operated with the sample and cantilever in fluids. As examples of its applications, images of living cells in Petri dishes and a 6 in. (15.24 mm) silicon wafer are included.

International audience; High-resolution pollen records from North America show that terrestrial environments were affected by Dansgaard-Oeschger (D-O) and Heinrich climate variability during the last glacial. In the western, more mountainous regions, these climate changes are generally observed in the pollen records as altitudinal movements of climate-sensitive plant species, whereas in the southeast, they are recorded as latitudinal shifts in vegetation. Heinrich (HS) and Greenland (GS) stadials are generally correlated with cold and dry climate and Greenland interstadials (GI) with warm-wet phases. The pollen records from North America confirm that vegetation responds rapidly to millennial-scale climate variability, although the difficulties in establishing independent age models for the pollen records make determination of the absolute phasing of the records to surface temperatures in Greenland somewhat uncertain.

Forty nine patients with rectosigmoid carcinoma considered unsuitable for surgery underwent endoscopic Nd:YAG laser treatment for palliation of symptoms and tumour eradication, if feasible. Altogether 25 (51%) of the lesions had distal margins less than 7 cm from the anus and 36 (73%) extended above the peritoneal reflection. In seven patients with tumours less than 3 cm in diameter, symptomatic improvement was achieved in all (mean follow up 16 months) and complete tumour eradication in three. In the remaining 42 patients with larger tumours (34 greater than 2/3 circumferential, mean length 5.5 cm), symptomatic improvement was achieved with repeated treatments (average 3.4) in 31 (74%) over a mean follow up of 19 weeks. Of the parameters assessed, only circumferential tumour extent proved significant in predicting functional outcome after treatment. All treatment failures (eight initial, three late) occurred in patients with extensive tumours, and only seven of these patients were considered fit for colostomy. Bowel perforation occurred in two patients (5%) but there was no treatment-related mortality. Mean stay in hospital for all laser treatments was nine days (30% were outpatient attendances). These results suggest that laser therapy may be the palliative treatment of choice in patients with rectal carcinoma unsuitable for surgery.

tached to the arthropod host by a basal holdfast. The holdfast is composed of an amorphous cement secreted from one end ofthe thallus through discrete pores (Whisler and Fuller, 1968). Amoebidium parasiticum is found on the external cu? ticle of a number of aquatic Crustacea (Branchiopoda, Amphipoda, Isopoda, Copepoda and Cladocera) and Insecta, including larvae of Dip? tera (Chironomidae, Culicidae), Ephemeroptera, Trichoptera, and in the rectum of Odonata (Lichtwardt, 1986). Contrary to the specific ep? ithet, the fungus does not penetrate the host cu? ticle and has not been reported to be parasitic. Amoebidium parasiticum was the first axenically cultured trichomycete (Whisler, 1960,1962). The fungus has been placed in the order Amoebidales (Lichtwardt, 1986) and may reproduce by amoeboid cells which encyst and form cytospores, or by sporangiospores. Typically, reproduction is by the sporangio? spore phase where growth occurs from a sporan? giospore to a mature thallus apparently in the presence of a low calcium ion concentration. Un? der standard culture conditions, the young thal? lus enlarges in size and nuclear number until the cell reaches a mature length of approximately 52 pm. The cytoplasm cleaves into approximately 13 diagonally elongated sporangiospores which increase in volume and rupture the sporangial wall (Whisler, 1968). In the alternate reproductive pathway amoebae are produced instead of sporangiospores. In this pathway, under culture conditions, the thallus enlarges in volume and nuclear number until the cell reaches a length of approximately 45 pm, at which time a transverse cytoplasmic cleavage occurs, in contrast to the diagonally oriented cleavage of sporangiospore formation; in nature there can be sizable varia? tion in thallus dimensions. No wall forms around the cleaved units, and as the thallus wall ruptures, naked amoebae escape. Following a period of active migration, the amoebae become rotund and inactive and deposit a wall to form a cyst (Whisler, 1966,1968). Whisler (1966,1968) outlined several factors which may induce A. parasiticum to switch from the sporangiospore phase to the amoeba-cyst phase in its life cycle under laboratory conditions. A dialyzed extract of daphnids (of unknown composition) induced amoebagenesis. A pH value near 8, and a tem? perature near 30 C and a relatively high calcium concentration (about 0.01 M) were optimal for amoeba formation.

Buffer layer configurations consisting of magnetron sputtered ZrO2, Zr–Si mixed oxide, and SiO2 were investigated for sputter deposition of Bi–Sr–Ca–Cu–O high‐Tc superconducting thin films onto silicon wafers. A problem associated with film flaking during postdeposition annealing was overcome by burying the sample in a powder of Bi–Sr–Ca–Cu–O material. Crack growth and buckling in the buffer layers, associated with differential thermal expansions, were eliminated by raising the deposition temperature for the buffer layers. Unfortunately, the improved buffer layers were not good enough to prevent substrate–film interactions over the long annealing times (e.g., 14 h), and the sufficiently high temperature (e.g., 850 °C) needed for the formation of the 2223 high Tc (110 K) phase.

Optical systems including those applied in the areas of optical communication and optically assisted chemistry can involve energies of the order of 0.1 to 3 watts deposited in system optical elements. These energy levels are sufficient to induce significant bending of elements due to thermal gradients and to raise average elements temperature substantially. We have considered several forms of fused silica and ULE mirrors that control both the gradient induced bending and reduce the overall temperature rise. These mirror forms make use of high thermal conductivity materials bonded to the basic mirror and applications of conductively coupled heat sinks to reduce the effects of the thermal loads. We have found that a typical 2.5 cm diameter beam will result in surface deformations of less than 0.004 microns (peak) per deposited watt for steady-state conditions. For symmetric loading the majority of this deformation is found to be power. Finite element models of several mirror forms have been utilized to predict the detailed deflection distribution of the thermally loaded mirrors. Nastran predicted deflections were then decomposed into Zernike polynomial representations of the surface. By utilizing material choice as a degree of freedom in multi-element system design, we have found it possible to define beam handling systems that have very little thermally induced defocus for symmetric thermal loading. Heat rejection from the system utilizes controlled conduction to minimize structural deflections of the supporting structure. For asymmetric loading, higher order aberrations begin to appear and the control of thermally induced system wavefront error becomes more difficult. The major aberration, however, continues to be power for a significant range of beam decenter. Mounting geometry, thermal conductor configuration and bonding effects were included in the analysis. Good agreement between closed form and finite element analysis results was found for simplified check cases.