UK PubMed Central (United Kingdom)

Citrate and lactose fermentation are subject to the same metabolic regulation. In both processes, pyruvate is the key intermediate. Lactococcus lactis subsp. lactis...Full Text Available

UK PubMed Central (United Kingdom)

Tetracycline-resistant Lactococcus lactis strains originally isolated from Polish raw milk were analyzed for the ability to transfer their antibiotic resistance genes in vitro, using...Full Text Available

UK PubMed Central (United Kingdom)

We studied how the introduction of an additional ATP-consuming reaction affects the metabolic fluxes in Lactococcus lactis. Genes encoding the hydrolytic part of the F₁ domain...Full Text Available

UK PubMed Central (United Kingdom)

The mechanism of metabolic energy production by malolactic fermentation in Lactococcus lactis has been investigated. In the presence of L-malate, a proton motive force composed of a membrane potential...Full Text Available

British Library Electronic Table of Contents (United Kingdom)

Abstract In the 1990s, significant efforts were invested in the research and development of food-grade expression systems in lactic acid bacteria (LAB). At this time, Lactococcus lactis in particular was demonstrated to be an ideal cell factory for the food-grade production of recombinant proteins. Steady progress has since been made in research on LAB, including Lactococcus, Lactobacillus and Streptococcus, in the areas of recombinant enzyme production, industrial food fermentation, and gene and metabolic pathway regulation. Over the past decade, this work has also led to new approaches on chromosomal integration vectors and host/vector systems. These newly constructed food-grade gene expression systems were designed with specific attention to self-cloning strategies, food-grade selection...

Science.gov (United States)

metric temperatures has been prepared showing the surface water temper- ... occasion, gray levels show different densities for similar water temper- ...

UK PubMed Central (United Kingdom)

Background and AimsIn spatially heterogeneous environments, a trade-off between seedling survival and relative growth rate may promote the coexistence of plant species. In temperate...Full Text Available

Science.gov (United States)

... While the large tanks served to regulate the water temper- ature, the polypropylene aquaria served as independent experimental units. ...

Science.gov (United States)

... The performance at reduced condenser water temper- atures was assumed to be the same as that of the single-effect unit. ...

Science.gov (United States)

... 6.29;Temperate Pinus forest: 5.43;Temperate deciduous broad-leaved forest: 5.41;Boreal Larix deciduous forest: 4.63;Temperate evergreen sclerophyllous broad-leaved forest: 4.23Tropical deciduous broad-leav...

Science.gov (United States)

... should give full con- As for the effects of the Three Gorges on the mouth of sideration to the rising water process and water temper- the river, the ...

British Library Electronic Table of Contents (United Kingdom)

Abstract Question: How do the diversity, size structure, and spatial pattern of woody species in a temperate (Mediterranean climate) forest compare to temperate and tropical forests? Location: Mixed evergreen coastal forest in the Santa Cruz Mountains, California, USA. Methods: We mapped, tagged, identified, and measured all woody stems (?1 cm diameter) in a 6-ha forest plot, following Center for Tropical Forest Science protocols. We compared patterns to those found in 14 tropical and 12 temperate forest plots. Results: The forest is dominated by Douglas-fir (Pseudotsuga menziesii) and three species of Fagaceae (Quercus agrifolia, Q. parvula var. shrevei, and Lithocarpus densiflorus), and includes 31 woody species and 8180 individuals. Much of the diversity was in small-diameter shrubs,...

British Library Electronic Table of Contents (United Kingdom)

This randomized, placebo-controlled, double blind, parallel dose-response study investigated the impact of 4-week commercial yoghurt consumption supplemented with Bifidobacterium animalis subsp. lactis (BB-12) and Lactobacillus acidophilus (LA-5) on fecal bacterial counts of healthy adults. Fifty-eight volunteers were randomly assigned to three different groups: 1. placebo (no probiotic, no starter and no green tea extract); 2. Yoptimal (10^9cfu/100g of BB-12 and LA-5 and 40mg of green tea extract) and 3. Yoptimal-10 (10^1^0cfu/100g of BB-12, 10^9cfu/100g of LA-5 and 40mg of green tea extract). These yoghurt products also contained Lactobacillus delbrueckii subsp. bulgaricus (10^7cfu/100g) and Streptococcus thermophilus (10^1^0cfu/100g). The quantitative PCR (qPCR) results showed that ther...

British Library Electronic Table of Contents (United Kingdom)

Abstract A large remaining source of uncertainty in global model predictions of future climate is how ecosystem carbon (C) cycle feedbacks to climate change. We conducted a field manipulative experiment of warming and nitrogen (N) addition in a temperate steppe in northern China during two contrasting hydrological growing seasons in 2006 [wet with total precipitation 11.2% above the long-term mean (348 mm)] and 2007 (dry with total precipitation 46.7% below the long-term mean). Irrespective of strong intra- and interannual variations in ecosystem C fluxes, responses of ecosystem C fluxes to warming and N addition did not change between the two growing seasons, suggesting independence of warming and N responses of net ecosystem C exchange (NEE) upon hydrological variations in the temperate ...

UK PubMed Central (United Kingdom)

Background and AimsTrade-offs are fundamental to life-history theory, and the leaf size vs. number trade-off has recently been suggested to be of importance to our understanding...Full Text Available

UK PubMed Central (United Kingdom)

Nickel was established as an essential micronutrient for the growth of temperate cereal crops. Grain from barley (Hordeum vulgare L. cv `Onda'; containing 40 to 80 nanograms of Ni per...Full Text Available

UK PubMed Central (United Kingdom)

Although salamanders are characteristic amphibians in Holarctic temperate habitats, in tropical regions they have diversified evolutionarily only in tropical America. An adaptive radiation centered...Full Text Available

Energy Technology Data Exchange (ETDEWEB)

Creep properties of modified 9 Cr-1 Mo steel, an alloy significantly improved in elevated-temperature strength over 2 1/4 Cr-1 Mo and other similar alloys, are presented here. Data are primarily on material in the normalized and tempered condition. Effects of variables such as isothermal annealing treatment, cold work, normalizing temperature, tempering temperature, notch, and biaxial stress state have also been examined. Data analysis and comparisons have shown that modified 9 Cr-1 Mo alloy is very insensitive in response to several material variables, heat treatments, and specimen design variables.

Energy Technology Data Exchange (ETDEWEB)

The influences of temperature and duration of tempering on hardness and microstructure were investigated at high-temperature martensitic and low-carbon steels with 9% chrome and the further alloying elements molybdenium, vanadium, niobium and partially tungsten. After austenitizing and subsequent air cooling the steels were tempered at temperatures below, at and above Ac{sub 1b} for different times and finally a hardness test was performed. Making use of the temperature dependence of the hardness tempering diagrams were constructed and the Hollomon-Jaffe-Parameter on the three steels was determined within its application limits. Micrographs of the structure shows the formation of the carbides and the martensite. At tempering temperatures below Ac{sub 1b} a decrease of hardness occurs, above Ac{sub 1b}, a hardness rise due to the partial austenitizing was obtained. While hardening below Ac{sub 1b}, the ...

British Library Electronic Table of Contents (United Kingdom)

Soil acidification via acid precipitation is recognized to have detrimental impacts on forest ecosystems, which is in part associated with the function of ethylene released from the soil. However, the impacts of acidification on the cycling of ethylene in forest soils have not been fully taken into consideration in global change studies. Forest topsoils (0?5 cm) under four temperate forest stands were sampled to study the effects of a pH change on the emissions of ethylene and carbon dioxide from the soils and concentrations of dissolved organic carbon (DOC) released into the soils. Increasing acidification or alkalinization of forest soils could increase concentrations of DOC released into the soils under anoxic and oxic conditions. The ethylene emission from these forest topsoils could s...

Environmental Research Database

DescriptionChanges in glacier mass balance are critically influenced by the distribution of snow accumulation at the start of the melt season, but models of the winter season lag seriously behind those of the melt season. The overall aim is to test physically-based models of the spatial and temporal evolution of the winter snowpack at a temperate ice cap (Langjokull, Iceland), to assess how effectively and also how efficiently they capture variation in winter accumulation. A three-step modelling approach i [continued...

Energy Technology Data Exchange (ETDEWEB)

This report describes work accomplished in the project, titled ''Development of Appropriate Resistance Spot Welding Practice for Transformation-Hardened Steels.'' The Phase 1 of the program involved development of in-situ temper diagrams for two gauges of representative dual-phase and martensitic grades of steels. The results showed that tempering is an effective way of reducing hold-time sensitivity (HTS) in hardenable high-strength sheet steels. In Phase 2, post-weld cooling rate techniques, incorporating tempering, were evaluated to reduce HTS for the same four steels. Three alternative methods, viz., post-heating, downsloping, and spike tempering, for HTS reduction were investigated. Downsloping was selected for detailed additional study, as it appeared to be the most promising of the cooling rate control methods. The downsloping maps for each of the candidate ...

Energy Technology Data Exchange (ETDEWEB)

Hard surface finishing represents the final manufacturing step for functional areas of machine elements in state-of-the-art production. Raceways of rolling bearing rings are ground and honed to the required low roughness. Plastic deformation is restricted to a narrow edge zone of the hardened steel. Reheating of the machined components below the martensite tempering or bainite transformation temperature results in a marked decrease of the XRD line width on the surface. The investigated samples are made of through-hardened standard bearing steel 100Cr6 (international denotation: SAE 52100). On the basis of a material model that explains the effect as a complex diffusion process of dislocational carbon segregation, i.e. static strain aging, the measured kinetics of the XRD line width reduction is simulated by an Arrhenius-type equation, which describes the rate-controlling reaction step of temper carbide dissolution. The formation of a small ...

Energy Technology Data Exchange (ETDEWEB)

The effect of microalloying with carbide-forming (V,Ti,Nb) and rare-earth elements and of high-temperature thermomechanical processing (HTMP) on the structure, mechanical properties and low temperature behaviour of 38CrSi steel has been investigated. It has been shown that in the case of dissolution of carbides during heating for quench hardening, the tempering resistance of the steel increases. It has also been found that - as a result of HTMP - the susceptibility of the steel irreversible temper brittleness decreases, irrespective of the steel having been microalloyed or not. The data, originating from tensile testing and impact testing (with the help of laser interferometry) in the temperature range from +20 to -196 degC, has been explained in terms of fractographic analysis. It has been shown that microalloying and HTMP favour the occurrence of ductile microvoids in the fracture. On the other hand, HTMP and rare-earth elements changes the ...

Energy Technology Data Exchange (ETDEWEB)

Contents include: countermeasures to save energy of sintering plant and future plans in fukuyama works; improvement of surface quality of continuous-casting slab; development of direct quenching and tempering type HT80 steel with good weldability; numerical analysis of fluid flow in a geothermal reservoir; the finite-element calculation of turbulent flow using the universal law of the wall; development of PC 4 dual fuel engine; design of industrialized housing; Computer-aided Navigation system (CANSY); and new production control system in Fukuyama Works.

Energy Technology Data Exchange (ETDEWEB)

The method is used for repairing armored logging cables. It consists of preparing armor, subsequent connection of current-conducting strands and wires of the armor, and laying of the armor. Sections of connecting the wires of the armor of the lower and upper layers are scattered over the length of the fused section of the cable. In order to improve the fault strength of the cable, the junctions of connection of the armor wires are scattered among themselves at a distance determined by the Euler formula, and thermal tempering of the wire sections is carried out near these junctions, and then the fused section of the cable is reinforced.

Energy Technology Data Exchange (ETDEWEB)

A Paderborn group of builder-owners decided in favour of so-called concrete core activation or isothermal component tempering as an alternative to conventional air conditioning. Results are now available for the first year of operation. [German] Am eigenen Neubau hat eine Paderborner Bauherrengemeinschaft die sogenannte Betonkernaktivierung - oder wie es die Bauherren nennen, isotherme Baukoerpertemperierung - als Alternative zu einer konventionellen Klimaanlage installiert. Inzwischen liegen die Messergebnisse von der ueber einjaehrigen Betriebszeit vor. (orig.)

International Nuclear Information System (INIS)

Effect of helium and hydrogen production on radiation-hardening of F82H irradiated by dual or triple beam condition were investigated. The specimens used were four types of ferritic martensitic steels of F82H-std (Fe-8Cr-2W-0.2V-0.04Ta-0.1C) steels tempered at 750degC for 60 minutes, 20% cold worked F82H steel, F82H tempered for 10 minutes and non-tempered F82H steels. The irradiation was performed at 450degC to 50 dpa under simultaneous dual beams of 10.5 MeV Fe"3"+ and 1.05 MeV He"+ or triple beams of those and 380 keV H"+ ions. The ratios of He (appm)/dpa and H(appm)/dpa were 15 nad 15 (or 150) for dual and triple ion beams. The hardness of the irradiated specimens measured at room temperature using a micro indentation after the irradiations. The hardness in these F82H steels irradiated at 450degC to 18 dpa under triple beam irradiation was harder than that under dual beam irradiation. Irradiation softening and hardening ...

British Library Electronic Table of Contents (United Kingdom)

This study investigates the turnover of polysaccharides by heterotrophic bacterioplankton in the northern Bay of Biscay, a productive marine system on the continental margin of the temperate Atlantic Ocean. Bacterial biomass production (BBP) near the surface ranged from 0.5 to 25.7 nmol C L?1 h?1 during small phytoplankton blooms in May and June that occurred after the main spring bloom. A direct relationship between BBP and total polysaccharides strongly suggests the dependence of bacterial growth on the availability of semi-labile organic matter. Concentrations of combined glucose as well as rate constants of extracellular glucosidase activity and glucose uptake were determined to estimate the actual carbon fluxes from bacterial polysaccharide turnover. Results reveal that ...

Energy Technology Data Exchange (ETDEWEB)

This paper summarizes the results of a long-term research project by SKBV which aimed to find ways of increasing spiral chute capacity while minimizing particle degradation, and also to extend the life of chute linings. Spiral chutes have been redesigned in such a way that chute speeds are considerably slower. The most wear-resistant and economic material for the inlet area was found to be slabs of tempered alloy cast steel, and for normal chute sections, cast basalt plates. Vertical rom bunkers can now be lined with thin cladding sections of GRC. Staple pit spiral chutes have been considerably improved in respect to wear and abrasion by the use of toughened steel as the chute lining material. Several of the innovations developed during the course of the research project are in use in West German mines and some have also been introduced abroad. (In German)

Energy Technology Data Exchange (ETDEWEB)

Mechanical properties of P-LDHA and V-ROL N steels of the Czech production are compared with other ultra-high strength steels produced in the world. The most important results can be summarized into following points: 1. Optimally heat treated P-LDHA steel exhibits substantially better strength characteristics then the V-ROL N steel. 2. Optimal tempering temperature of the P-LDHA steel is 300 C. 3. Basic mechanical properties of P-LDHA steel belong to the top of the UHS steels ranking and are well comparable with those of American 300 M steel. 4. In the low-cycle fatigue region, the P-LDHA steel exhibits slightly better fatigue resistance then the 300 M steel. On the other hand, the high-cycle fatigue resistance of 300 M steel is slightly better then that of the P-LDHA steel. (orig.)

British Library Electronic Table of Contents (United Kingdom)

Commercial rolled magnesium sheets of alloys AZ31 (Mg-3 mass%Al-1 mass%Zn) and ZE10 (Mg-1 mass% Zn-<1 mass% Rare Earths) in O-temper condition were used for blanking experiments near room temperature. A serrated fracture surface can be observed in case of AZ31 but not in case of ZE10. During the shearing process of the AZ31 sheet, many micro cracks parallel to the sheet plane are generated in the shearing zone. These micro cracks lead to the formation of loose particles during the shearing operation, which interfere with further processing of the part and incur additional costs by increasing the scrap rate. It is found that the strong basal texture of this alloy is an important reason for the generation of such serrated cracks. In this paper a new method of selective texture modification i...

Energy Technology Data Exchange (ETDEWEB)

This paper describes how hydrogen transport affects the severity of hydrogen embrittlement in 300 M and AerMet100 ultra high strength steels. Slow strain rate tests were carried out on specimens coated with electrodeposited cadmium and aluminium-based SermeTel 1140/962. Hydrogen diffusivities were measured using two-cell permeation and galvanostatic charging methods and values of 8.0 x 10{sup -8} and 1.0 x 10{sup -9} cm{sup 2} s{sup -1} were obtained for 300 M and AerMet100, respectively. A two-dimensional diffusion model was used to predict the hydrogen distributions in the SSR specimens at the time of failure. The superior embrittlement resistance of AerMet100 was attributed to reverted austenite forming around martensite laths during tempering.

British Library Electronic Table of Contents (United Kingdom)

The effects of a modifier that contains Rare Earths (RE), low melting point alloy (Al-Bi-Sb) and Ca-Si alloy on an ultrahigh carbon steel containing 1.9wt.% C were studied. Microstructure characterization was carried out with optical microscopy (OM) and scanning electronic microscopy (SEM) combined with energy-dispersive spectrometry (EDS). Upon modification, the continuous eutectic carbide network structure was broken up and changed to a partly isolated and finer blocky structure in the as-cast alloy. Differential scanning calorimetry (DSC) revealed that the eutectoid temperature increased and the eutectic temperature decreased for the modified alloy. Modification also improved the impact toughness of the tempered steel, with a significant increase from 6.5 to 12.6Jcm^-^2, despite the har...

International Nuclear Information System (INIS)

There are reported the results of corrosion resistance investigation of aluminium bronzes, containing about 8 and 10% of aluminium and modifying quantities of zirconium. The tests of corrosion resistance were carried out in synthetic seawater, in 3% NaCl aqueous solution and in 10% H_2SO_4 aqueous solution, with reference to industrial bronze BA93 (CuAl9Fe3). The bronzes were tested in an annealed, hardened, tempered state and after plastic hot working. The conclusion is that corrosion resistance of aluminium bronzes, especially against selective corrosion, depends more on material structure, resulted form heat treatment, than on chemical composition. (author). 6 refs, 8 figs, 6 tabs.

Energy Technology Data Exchange (ETDEWEB)

The performance of advanced ceramics under cavitation loading in distilled water was studied by using a laboratory test with vibration-induced cavitation following the pattern of the ASTM standard G32-92. The hardened and tempered martensitic steel 100Cr6 was used as a reference. The aim was to identify mechanisms and the effects of important microstructural parameters on damage of polished Al{sub 2}O{sub 3}, Al{sub 2}O{sub 3}-ZrO{sub 2}, ZrO{sub 2} and SiC ceramics. Results showed that surface damage of brittle ceramics was mainly dominated by intergranular fracture, followed by detachment of single grains or fragments of them. Both incubation time and erosion rate were affected by the amount of initial surface cavities, grain sizes and secondary phases at grain boundaries. (orig.)

British Library Electronic Table of Contents (United Kingdom)

Science plays paradoxical roles in environmental planning. As a process for generating and adapting knowledge of the biophysical environment to human use, it is essential to achieving sustainability. As the socially contested evaluation of competing claims to truth, however, adversarial science often becomes the focus of conflict in the planning process. British Columbia's Central Coast Land and Resource Management Plan (CCLRMP) planning process took place amid industrial restructuring, market campaigns, and scientific disputes over the conservation of the world's largest remaining temperate rainforest. This article shows how adversarial science set the terms of the policy debate, as well as the means for compromise. A multisector interdisciplinary information team played a key role in arr...

International Nuclear Information System (INIS)

Effects of helium and hydrogen production on irradiation hardening of martensitic steel F82H (Fe-8Cr-2W-0.2V-0.04Ta-0.1C) were examined by dual or triple beam experiments. The effects of tempering and cold working were also examined. The irradiations were performed at about 500degC to 50 dpa under simultaneous dual beams of 10.5 MeV Fe"3"+ and 1.05 MeV He"+ or triple beams of those and 380 keV H"+ ions. The value of appm-He/dpa for the dual ion beams was about 15, and the values of appm-He/dpa and appm-H/dpa for the triple ion beams were 15 and 15 (or 150), respectively. The hardness of the irradiated specimens measured at room temperature using a micro indentation after the irradiations. Irradiation softening and hardening was observed in F82H-std, F82H+20%CW and a non-tempered F82H steels irradiated at about 500degC to 18 and 50 dpa, respectively, by dual ion beams. The hardness of the specimens irradiated at about 500degC to 18 dpa under ...

Energy Technology Data Exchange (ETDEWEB)

The effect of accelerated thermal cycling on a joint between modified 9Cr-1Mo steel (Grade 91) and Alloy 800 welded with Inconel 82 and 182 filler material is discussed. This is part of a trimetallic transition joint involving Grade 91-Alloy 800-316LN austenitic stainless steel for steam generator application. It has been shown that, during thermal cycling following the typical post-weld tempering treatment at 760 deg. C for 2 h, no carbon diffusion occurs from the ferritic steel towards the weld metal. There is, in fact, a hardness increase at the ferritic steel/weld metal interface which is probably a result of work hardening. Carbon migration sets in only after unusually long post-weld heat treatments for 20 and 50 h at 760 deg. C followed by thermal cycling. Significantly, even under the most severe thermal cycling test conditions imposed, no cracking or oxide notching could be detected, thus demonstrating the superior performance potential of modified 9Cr-1Mo ...

Energy Technology Data Exchange (ETDEWEB)

The aim of this work is to describe the processes during plasma nitriding of Nb-containing, powder metallurgy prepared (PM) tool steel. PM steel was studied containing 2.5% C, 3.3% Si, 6.2% Cr, 2.2% Mo, 2.6% V, 2.6% Nb and 1.0% W, produced by melt atomization and hot isostatic pressing. The hardened and tempered steel was plasma nitrided at temperatures ranging from 470 to 530 deg. C. The nitriding time was 30-180 min. Optical microscopy, electron microscopy, XRD, EDS, WDS and hardness measurements were used to study the steel's properties, microstructure, phases and chemical composition. The nitriding temperature of 470 deg. C was found to be unsuitable for practical use because the layers prepared at this temperature were non-uniform. The compound layer formed by M{sub 2,3}(C,N) and M{sub 4}N was found after nitriding at temperatures of 500 and 530 deg. C for at least 60 min. The effect of niobium on the formation of this layer was studied.

International Nuclear Information System (INIS)

In this work we report a study of the induced changes in structure and corrosion behavior of martensitic stainless steels nitrided by plasma immersion ion implantation (PI"3) at different previous heat treatments. The samples were characterized by x-ray diffraction and glancing angle x-ray diffraction, scanning electron microscopy, energy dispersive x-ray spectroscopy, and potentiodynamic measurements. Depending on the proportion of retained austenite in the unimplanted material, different phase transformations are obtained at lower and intermediate temperatures of nitrogen implantation. At higher temperatures, the great mobility of the chromium yields CrN segregations like spots in random distribution, and the #alpha#"'-martensite is degraded to#alpha#-Fe (ferrite). The nitrided layer thickness follows a fairly linear relationship with the temperature and a parabolic law with the process time. The corrosion resistance depends strongly on chromium segregation from the martensitic ...

Environmental Research Database

ObjectivesThe overall objective of the proposal is to test the conclusions reached in a recent article by Magnani, Mencuccini et al (2007), in which we proposed for the first time that the Net Ecosystem Productivity (NEP) of forests of the temperate and boreal region does not depend on temperature or rainfall but, rather, on nitrogen deposition (Ndep) from the atmosphere. It is widely accepted that Ndep can increase forest C sequestration, however the results from our 2007 paper reported a sensitivity dC/ [continued...]DescriptionCombustion of fossil fuels and use of fertilisers in agriculture has increased the amount of nitrogen compounds present in the atmosphere and the biosphere. More atmospheric nitrogen is converted into reactive nitrogen by anthropogenic activities than by all natural processes combined. This phenomenal historical increase in nitrogen deposition is responsible for several serious environmental problems, such as soil acidification and ...

Energy Technology Data Exchange (ETDEWEB)

With regard to long-term high-temperature strength, molybdenum is an effective alloying element but rather expensive as well. The author describes its influence on high-temperature strength properties of CrMoV alloyed steel. Besides molybdenum, also vanadium and carbon have an increasing effect on limiting rupture stress which furthermore may be effected by heat treatment, the cooling rate being a dominating factor in this process. To guarantee optimum long-term high-temperature strength properties, a minimum of a least 0.5% Mo and 0.35% V is required. The cooling rate after austentizing must be high enough to enable transformation in the bainitic structure to take place. A two-to-three-hour tempering treatment at about 720/sup 0/C is regarded as an optimum.

Science.gov (United States)

Antibodies to Ehrlichia canis were detected by indirect immunofluorescence in sera from 233 of 2,077 (11%) military working dogs in various locations throughout the world and from 535 of 938 (57%) civilian dogs in the United States during a 1-year period of study. Overall, E canis infection rates ranged from 13% in the tropical and temperate zones below 45 degrees N to 8% in the cold zone north of 45 degrees N latitude. The highest antibody prevalence rate (24%) was found among a select population of dogs stationed between 40 degrees and 45 degrees north latitude (Japan and Okinawa). The seropositive military dogs did not have clinical signs of ehrlichiosis, thus indicating that the predominant form of infection was subclinical. On the other hand, 216 (23%) of the seropositive civilian dogs had various signs of the disease. The difference was attributed to the fact that the sera from civilian dogs were submitted by practitioners who suspected the disease. ...

Science.gov (United States)

Development of a high performance air heater through use of an evacuated tube cover design is described. The cover design utilizes evacuated fluorescent light tubes laid parallel in a close packed array to form an inner transparent glazing over a conventional metal absorber plate with flow behind the plate. A tempered flat glass plate was used as an outer glazing. Both clear and infrared reflective (IR) tubes were investigated. Solar transmittance tests indicate that the clear tube array has a higher transmittance than two flat sheets of low-iron glass. The IR coating produced substantial transmittance loss. Thermal conductance tests indicate that the tubes behave similar to two flat glass sheets with a vacuum in between. The IR reflective coating was only marginally effective at reducing heat conductance. Final prototype designs are presented along with collector performance estimates.

CERN Document Server

Correlations are studied between the power density of Alfv\\'en-cyclotron waves (having frequencies between 0.02 and 2 Hz) and the ratio of the perpendicular and parallel temperature of the protons. The wave power spectrum is evaluated from high-resolution 3D magnetic field vector components, and the ion temperatures are derived from the velocity distribution functions as measured in fast solar wind during the Helios-2 primary mission at radial distances from the Sun between 0.3 AU and 0.9 AU. From our statistical analysis, we obtain a striking correlation between the increases in the proton temperature ratio and enhancements in the wave power spectrum. Near the Sun the transverse part of the wave power is often found to be by more than an order of magnitude higher than its longitudinal counterpart. Also the measured ion temperature anisotropy appears to be limited by the theoretical threshold value for the ion-cyclotron instability. This suggests that high-frequency Alfv\\'{e}n waves ...

Science.gov (United States)

Penicillium crustosum is common in food and feed both in subtropical and temperate regions. Recently, it has also been found occurring frequently in glacier ice, sea ice and sea water of Arctic regions of Svalbard. The aim of the study was to compare isolates of the same fungal species from widely different habitats and geographic regions to see if the nutritional physiology and the profile of secondary metabolites were consistent or depended on the isolation source. All 121 strains examined produced the following families of secondary metabolites: penitrems (100%), roquefortines (100%), terrestric acids (99.2%) and viridicatols (100%), whereas 81 of 83 Arctic isolates additionally produced andrastin A. However, only 8 of 38 non-Arctic isolates produced detectable andrastin A. The quantitative profiles of 96 strains were compared using cluster, principal component and correspondence analyses. There was no clear grouping of Arctic versus non-Arctic, creatine ...

Energy Technology Data Exchange (ETDEWEB)

This article discusses the proper use of sandy land in China from the viewpoint of ecology. The many low-yield fields in every locality across China include sandy land that is unsuited to the cultivation of grains such as paddy rice, corn and wheat. Separate investigations of the northern plain and the southern coast between 1980 and 1982 demonstrated that sandy land in a warm climatic zone (e.g. Huang He) is suited to peanuts, soybeans and other oil-bearing crops; that forestation can be carried out on sandy land in Inner Mongolia and Xinjiang; and that coastal sandy land has much salinity and is best suited to growing horsetail beefwood. Moreover, the creation of windbreaks along the coasts of southern China has lessened the threat of wind-blown sand which had made rice not worth cultivating on sandy land. It is concluded that different crops can be grown on the sandy soil of China's temperate, warm, semitropical and tropical zones.

Energy Technology Data Exchange (ETDEWEB)

The thesis relates to an investigation done on greenhouse gases in coniferous forest soils. The production of nitrous oxide (N{sub 2}O) and carbon dioxide (CO{sub 2}), and the consumption of methane (CH{sub 4}) in a temperate forest soil were studied by a rapid and sensitive gas chromatographic (GC) method for analysing all three greenhouse gases at or below ambient levels. Gas fluxes were measured in soil incubation and lysimeter experiments. 15 soil samples were taken at random within a 100 m{sup 2} area in a Norway spruce forest stand (Picea abies). The fluxes of N{sub 2}O, CH{sub 4} and CO{sub 2} were measured under standardized laboratory incubation conditions to investigate spatial variability in relation to other factors such as nitrogen (N) mineralization rate, nitrification rate, organic carbon (OC), total N and pH. The effects of temperature, soil moisture content, and ammonium addition were also studied in an incubation experiment. A more detailed study ...

Science.gov (United States)

Anthropogenic nitrogen (N) deposition affects many natural processes, including forest litter decomposition. Saprotrophic fungi are the only organisms capable of completely decomposing lignocellulosic (woody) litter in temperate ecosystems, and therefore the responses of fungi to N deposition are critical in understanding the effects of global change on the forest carbon cycle. Plant litter decomposition under elevated N has been intensively studied, with varying results. The complexity of forest floor biota and variability in litter quality have obscured N-elevation effects on decomposers. Field experiments often utilize standardized substrates and N-levels, but few studies have controlled the decay organisms. Decomposition of beech (Fagus sylvatica) blocks inoculated with two cord-forming basidiomycete fungi, Hypholoma fasciculare and Phanerochaete velutina, was compared experimentally under realistic levels of simulated N deposition at Wytham Wood, Oxfordshire, ...

Energy Technology Data Exchange (ETDEWEB)

This study explores the effects of atmospheric CO2 enrichment and climate change on soil moisture (W{sub r} ) and biome-level water limitation (L{sub TA}), using a dynamic global vegetation and water balance model forced by five different scenarios of change in temperature, precipitation, radiation, and atmospheric CO2 concentration, all based on the same IS92a emission scenario. L{sub TA} is defined as an index that quantifies the degree to which transpiration and photosynthesis are co-limited by soil water shortage (high values indicate low water limitation). Soil moisture decreases in many regions by 2071-2100 compared to 1961-1990, though the regional pattern of change differs substantially among the scenarios due primarily to differences in GCM-specific precipitation changes. In terms of L{sub TA}, ecosystems in northern temperate latitudes are at greatest risk of increasing water limitation, while in most other latitudes L{sub TA} tends to increase (but again ...

Energy Technology Data Exchange (ETDEWEB)

The Gulf of California represents one of the most productive and unique marginal seas in the world. The mouth of the Gulf captures warm equatorial water while annual wind patterns assure major upwelling of nutrient-rich water leading to a rich marine biota. These conditions have created a wide array of tropical through warm temperate carbonate environments. The most unusual of these environments is located in the La Paz region of Baja California Sur where tropical-subtropical water temperatures and low rainfall have allowed growth of corals, calcareous red algae, and other shelled invertebrates to form a carbonate bank environment. Sampling and mapping transacts in shallow bays north of La Paz and on the adjacent Espiritu Santo island have revealed a full spectrum of subenvironments including mangrove bordered, terrigenous mud dominated coastal zones, which grade into carbonate tidal flats. In addition, single coral heads as well as incipient reef structures ...

Energy Technology Data Exchange (ETDEWEB)

This paper reports the estimates concerning the atmospheric carbon dioxide absorption and storage by living plants all over the world. It is necessary to decrease atmospheric carbon dioxide concentrations for avoiding global warming. As living plants absorb carbon dioxide by photosynthesis and accumulate carbon in their bodies, they can play an important role to remove atmospheric carbon dioxide. Literatures describing distribution areas, biomass values and net primary productivity (NPP) of forests, marine plants and microorganisms were collected. Examining those data, the biomass and NPP of forests, marine plants and microorganisms can be summarized as follows: (1) Forest biomass and their NPP of the world. The world's forest area is recently estimated as 4 billion hectares, and their biomass is about 400 billion tons of carbon which is equal to 2/3 of the total atmospheric carbon. The NPP of the world's forest is estimated as 25-35 billion tons C/year. (2) Mean ...

Energy Technology Data Exchange (ETDEWEB)

Strain-controlled fatigue experiments under simultaneous irradiation have been performed to investigate the specific loadings of structural materials in next-step fusion devices. All irradiations were done on specimens made of the tempered ferritic/martensitic Cr steel MANET-I at 420 C using a 104 MeV [alpha]-particle beam. Continuous push-pull cycling (R=-1) has been applied with total strain ranges [Delta][epsilon][sub t] between 0.5 and 1.0%. Under in-beam conditions at e.g. [Delta][epsilon][sub t]= 0.5% a number of cycles to failure of N[sub f]=42000, a He concentration of 400 appm and a damage dose of 1.6 dpa has been reached. This N[sub f] is by about a factor of two below the average N[sub f]-value of unirradiated reference tests, but seven times higher than N[sub f] of comparable postirradiated specimens. It was found, that at least at 420 C conventional postirradiation tests are a conservative approach to in-situ conditions, and that in strain-controlled ...

International Nuclear Information System (INIS)

Due to thermal gradients and load changes steam-turbine casings suffer combined creep-fatigue loading. Creep and fatigue portions depend on service conditions. Special interest is focused on the behaviour of creep-fatigue cracks, originated from potential defects due to construction and manufacturing weldments, on residual lifetime assessment. The project deals with the crack-growth behaviour at 530deg C and r.t. of welded and unwelded heat-resistant cast steels: 1% CrMoV-cast (GS-17 CrMoV 5 11, two melts: low and high V-content) and 12% CrMoV-cast (G-X 22 CrMoV 12 1). The crack planes of CT-specimens investigated, taken from manual arc-welded plates, were situated in the heat-affected zone (HAZ). The fatigue, creep and combined creep-fatigue crack-growth behaviour was investigated by means of low-frequency (0.5 and 0.05 Hz) tests, holding-time (20 min) tests and constant load tests up to about 5 000 h. Metallographic investigations show that in the case of both 1% and 12% CrMoV-cast ...

Science.gov (United States)

No research has compared expressions of weight bias across different subgroups of obese individuals. This study compared attitudes toward and beliefs about obesity in women with and without binge eating disorder (BED) and examined whether these attitudes are related to psychological factors. Fifty obese women with BED were compared with an age- and body mass index (BMI)-matched group of 50 obese women without BED on a battery of established measures of anti-fat attitudes and beliefs about weight controllability and psychological factors (self-esteem, depression, and eating disorder features). The ageand BMI-matched groups did not differ with respect to beliefs about obesity or attitudes toward obese persons, or in self-esteem or depression. Correlational analyses conducted separately within each group revealed that women with BED who reported more favorable attitudes towards obese persons had higher self-esteem and lower levels of depression, whereas there were no significant ...

Energy Technology Data Exchange (ETDEWEB)

The precipitation hardened, ferrite-pearlite medium-carbon steels microalloyed with vanadium (AFP steels) have been developed over the last few years as materials allowing processing by controlled, continuous cooling down from forging temperatures, for achieving benefits such as reducing the number of required heat treatment and working processes and saving expensive alloying materials. Due to their cost-saving advantages, the steels rapidly have been accepted as an alternative material to the quenched and tempered steels and re particularly used for fabrication of automobile parts. Their drawbacks however are the lower yield strength, and low ductility and toughness as compared to the heat-treatable steels. The research project therefore was intended to enhance the properties of the microalloyed, medium-carbon steels and widen their applicability by establishing further and improving existing thermomechanical treatment processes that will considerably improve the ...

Energy Technology Data Exchange (ETDEWEB)

The study reports ultrasonography and computerise tomography findings in 16 patients with amoebic abscesses, 12 of whom lived in a temperate peripheral area north-east of Naples (Italy). All patients have a clinical-diagnostic condition called sub-urban amoebiasis. The personal experience with the US guided therapeutic drainage of amoebic abscess with repeated cavity washing, which is important for positive parasitology. Combined US and CT assessment facilitated the diagnosis of amoebiasis and its differentiation from pyogenic abscess and hepatoma. [Italian] La colonizzazione epatica rappresenta la localizzazione piu' comune dell'amebiasi extraintestinale e gli ascessi epatici ne costituiscono la manifestazione piu' frequente sviluppandosi nel 3-9 % dei pazienti affetti da infezione parassitaria. Diversi studi confermano che la terapia medica dell'amebiasi risulta piu' efficace quando viene associato il drenaggio ...

International Nuclear Information System (INIS)

Full text: The US commercial nuclear industry has just completed an outstanding decade of plant performance. Safety levels and electric production are at unprecedented high levels and continue to exceed even high industry goals. Nuclear energy continues to keep the highest priority on performance improvement programs and highly trained/qualified people that maintain its record setting safety and reliability of operations. While the industry has maintained a consistently high level of performance, the advent of deregulation and the consolidation of NPP ownership, as well as the current climate of concern about both rising energy costs and availability of power, has raised the standard for nuclear energy's level of competitiveness in today's market place. The resulting challenge is how to more effectively manage risk and improve performance even further in a generally high performing organization. Newer technology and more training by themselves are not the answer. Rather, the answer ...