Colonisation of winter wheat grain by Fusarium spp. and mycotoxin content as dependent on a wheat variety, crop rotation, a crop management system and weather conditions.

Science.gov (United States)

Czaban, Janusz; Wróblewska, Barbara; Sułek, Alicja; Mikos, Marzena; Boguszewska, Edyta; Podolska, Grażyna; Nieróbca, Anna

2015-01-01

Field experiments were conducted during three consecutive growing seasons (2007/08, 2008/09 and 2009/10) with four winter wheat (Triticum aestivum L.) cultivars - 'Bogatka', 'Kris', 'Satyna' and 'Tonacja' - grown on fields with a three-field crop rotation (winter triticale, spring barley, winter wheat) and in a four-field crop rotation experiment (spring wheat, spring cereals, winter rapeseed, winter wheat). After the harvest, kernels were surface disinfected with 2% NaOCl and then analysed for the internal infection by different species of Fusarium. Fusaria were isolated on Czapek-Dox iprodione dichloran agar medium and identified on the basis of macro- and micro-morphology on potato dextrose agar and synthetic nutrient agar media. The total wheat grain infection by Fusarium depended mainly on relative humidity (RH) and a rainfall during the flowering stage. Intensive rainfall and high RH in 2009 and 2010 in the period meant the proportions of infected kernels by the fungi were much higher than those in 2008 (lack of precipitation during anthesis). Weather conditions during the post-anthesis period changed the species composition of Fusarium communities internally colonising winter wheat grain. The cultivars significantly varied in the proportion of infected kernels by Fusarium spp. The growing season and type of crop rotation had a distinct effect on species composition of Fusarium communities colonising the grain inside. A trend of a higher percentage of the colonised kernels by the fungi in the grain from the systems using more fertilisers and pesticides as well as the buried straw could be perceived. The most frequent species in the grain were F. avenaceum, F. tricinctum and F. poae in 2008, and F. avenaceum, F. graminearum, F. tricinctum and F. poae in 2009 and 2010. The contents of deoxynivalenol and zearalenon in the grain were correlated with the percentage of kernels colonised by F. graminearum and were the highest in 2009 in the grain from the four

Accumulation of Cs, Sr into leaves and grain of winter wheat under act of N, Zn, Li, Na

International Nuclear Information System (INIS)

Grodzinsky, D.; Tkatchuk, K.; Zhmurko, N.; Bogdan, T.; Guralchuk, Zh.

1998-01-01

The experiments were carried out on cv Lutencens 7 winter wheat grown on grey forest soil. In order to study the influence of nitrogen on Cs and Sr accumulation, a background of P60 K60 added in autumn different doses of nitrogen (30, 60, 120 kg/ha) were applied in spring. The influence of micronutrients on Cs and Sr accumulation was studied by adding 3 kg/ha Zn and 2 kg/ha Li to the soil under ploughing on background of N60 P60 K60. Besides the foliar application with 0.05% Na 2 SO 4 was carried out. Cation content (Cs, Sn, Zn, Li, Na) in soil and plant organs was determined by atomic absorption spectrophotometry. The Cs, Sr content in control plant leaves made up 15.0 and 21.0 mg per g of dry matter at the early stages of plant development. As the plants aged, the content of those elements in the leaves decreased strongly (3-4 times). At early stages of plant development, nitrogen caused an 8.9-11% increase in the Cs content of the leaves. At the stages of heading to grain filling, the Cs content increase was only observed at a high nitrogen dose, whereas low nitrogen doses had no effected on Cs accumulation in leaves. In should be noted that nitrogen (N60 and N120) decreased the Cs content in grain by 32-33%. As for the Sr content of grain, this was 3 to 4-fold less than that of Cs. Nitrogen had no effected on the Sr content of grain. Zn and Li addition to soil as well as foliar nutrition with Na had a different effect on the Cs and Sr content of winter wheat leaves and grain. Addition of Li decreased the Cs and Sr content of old leaves by 13% and 25% respectively. Addition of Zn and Na decreased the Sr content of old leaves but had no effect on the Cs content. Zn, Na and Li reduced the Sr content in grain also, viz. by 16,11 and 7% respectively. Thus the research has demonstrated the possibility of regulating Cs and Sr accumulation in the above-ground organs of winter wheat plants

Factors limiting the grain protein content of organic winter wheat in south-eastern France: a mixed-model approach

NARCIS (Netherlands)

Casagrande, M.; David, C.; Valantin-Morison, M.; Makowski, D.; Jeuffroy, M.H.

2009-01-01

Organic agriculture could achieve the objectives of sustainable agriculture by banning the use of synthetic fertilizers and pesticides. However, organic crops generally show lower performances than conventional ones. In France, organic winter wheat production is characterized by low grain protein

Effect of nitrogen fertilizer application timing on nitrogen use efficiency and grain yield of winter wheat in Ireland

Directory of Open Access Journals (Sweden)

Efretuei A.

2016-06-01

Full Text Available The objectives of this work were to determine the effects of initiating application of fertilizer nitrogen (N to winter wheat at different growth stages (GSs on grain yield and N use efficiency (NUE. A factorial experiment was carried out in two growing seasons (2011 and 2012 with five timings of first N application (GS 24/26 [tillering], GS 30, GS 31, GS 32 or GS 37 and an unfertilized control, two sowing densities (100 and 400 seeds/m2 and a cattle slurry treatment (with or without slurry. The latter was included to simulate variation in soil N supply (SNS. Delaying the first application of N from the tillering stage until GS 30 had no significant effect on grain yield in either year. Further delaying the initial N application until GS 31 caused a significant yield reduction in 2011, in comparison to GS 30 application, but not in 2012. Differences in efficiency of recovery and use of fertilizer N by the crop among the first three application timings were small. There was no evidence to support alteration in the timing of the first application of N in response to low plant density. Slurry application did not influence SNS, so the interaction between SNS and fertilizer N application timing could not be determined. It is concluded that in order to maximise yield and NUE, the first N application should be applied to winter wheat between late tillering and GS 30 and that delaying the first N until GS 31 can lead to yield reductions compared to the yield obtained with earlier application.

Effect of the New Plant Growth Biostimulants Based on Amino Acids on Yield and Grain Quality of Winter Wheat.

Science.gov (United States)

Popko, Małgorzata; Michalak, Izabela; Wilk, Radosław; Gramza, Mateusz; Chojnacka, Katarzyna; Górecki, Henryk

2018-02-21

Field and laboratory experiments were carried out in 2012-2013, aimed at evaluating the influence of new products stimulating plant growth based on amino acids on crop yield, characteristics of grain and content of macro- and micronutrients in winter wheat ( Triticum aestivum L.). The tests included two formulations produced in cooperation with INTERMAG Co. (Olkusz, Poland)-AminoPrim and AminoHort, containing 15% and 20% amino acids, respectively, and 0.27% and 2.1% microelements, respectively. Field experiments showed that the application of products based on amino acids influenced the increase of grain yield of winter wheat (5.4% and 11%, respectively, for the application of AminoPrim at a dose 1.0 L/ha and AminoHort at dose 1.25 L/ha) when compared to the control group without biostimulant. Laboratory tests showed an increase of technological characteristics of grain such as ash content, Zeleny sedimentation index and content of protein. The use of the tested preparations at different doses also contributed to the increase of the nutrients content in grains, in particular copper (ranging 31-50%), as well as sodium (35-43%), calcium (4.3-7.9%) and molybdenum (3.9-16%). Biostimulants based on amino acids, tested in the present study, can be recommended for an efficient agricultural production.

Long-term Low Radiation Decreases Leaf Photosynthesis, Photochemical Efficiency and Grain Yield in Winter Wheat

DEFF Research Database (Denmark)

Mu, H; Jiang, D; Wollenweber, Bernd

2010-01-01

the impact of low radiation on crop growth, photosynthesis and yield. Grain yield losses and leaf area index (LAI) reduction were less than the reduction in solar radiation under both shading treatment in both cultivars. Compared with the control (S0), grain yield only reduced 6.4 % and 9.9 % under 22.......0-22.9 % (S1) and 29.5-49.6 % (S2), which was consistent with the reduction in radiation. The reduction in LAI was partially compensated by increases in the fraction of the top and bottom leaf area to the total leaf area, which facilitated to intercept more solar radiation by the canopy. The decrease......Low radiation reduces wheat grain yield in tree-crop intercropping systems in the major wheat planting area of China. Here, two winter wheat (Triticum aestivum L) cultivars, Yangmai 158 (shading tolerant) and Yangmai 11 (shading sensitive), were shaded from jointing to maturity to evaluate...

Higher Fusarium Toxin Accumulation in Grain of Winter Triticale Lines Inoculated with Fusarium culmorum as Compared with Wheat.

Science.gov (United States)

Góral, Tomasz; Wiśniewska, Halina; Ochodzki, Piotr; Walentyn-Góral, Dorota

2016-10-18

Resistance to Fusarium head blight in 32 winter triticale and 34 winter wheat accessions was evaluated. Triticale and wheat were sown in field experiments in two locations. At the time of flowering, heads were inoculated with three Fusarium culmorum isolates. Fusarium head blight index was scored and after the harvest percentage of Fusarium damaged kernels was assessed. Grain was analysed for type B trichothecenes (deoxynivalenol and derivatives, nivalenol) and zearalenone (ZEN) content. The average Fusarium head blight indexes were 28.0% for wheat and 19.2% for triticale accessions. The percentage of Fusarium damaged kernels was also higher for wheat and came to 55.6%, while for triticale this figure was 40.2%. The average content of deoxynivalenol (DON) for wheat amounted to 11.65 mg/kg and was lower than the result for triticale which was 14.12 mg/kg. The average contents of nivalenol were similar in both cereals: 4.13 mg/kg and 5.19 mg/kg for wheat and triticale respectively. Considerable amounts of DON derivatives in the cereals were also detected. The ZEN content in the grain was 0.60 mg/kg for wheat and 0.66 mg/kg for triticale. Relationships between Fusarium head blight index, Fusarium damaged kernels and mycotoxin contents were statistically significant for wheat and mostly insignificant for triticale. Triticale proved to have less infected heads and kernels than wheat. However, the content of type B trichothecenes was higher in triticale grain than in wheat grain.

The influence of sowing period and seeding norm on autumn vegetation, winter hardiness and yield of winter cereal crops

Directory of Open Access Journals (Sweden)

Potapova G. N.

2017-10-01

Full Text Available the winter wheat and triticale in the middle part of the Ural Mountains haven’t been seeded before. The technology of winter crop cultivation should be improved due to the production of new varieties of winter rye. Winter hardiness and yield of winter rye are higher in comparison with winter triticale and especially with winter wheat. The sowing period and the seeding rate influence the amount of yield and winter hardiness. The winter hardiness of winter cereals and the yield of the rye variety Iset sowed on August 25 and the yield of the triticale variety Bashkir short-stalked and wheat Kazanskaya 560 sowed on August 15 were higher. It is important to sow winter grain in local conditions in the second half of August. The sowing this period allows to provide plants with the necessary amount of positive temperatures (450–500 °C. This helps the plants to form 3–4 shoots of tillering and a mass of 10 dry plants reaching 3–5 grams. The winter grain crops in the middle part of the Ural Mountains should be sown with seeding rates of 6 and 7 million of sprouting grains per 1 ha, and the seeds must be cultivated with fungicidal preparation before seeding.

Root growth, soil water variation, and grain yield response of winter wheat to supplemental irrigation

Directory of Open Access Journals (Sweden)

Jianguo Man

2016-04-01

Full Text Available Water shortage threatens agricultural sustainability in the Huang-Huai-Hai Plain of China. Thus, we investigated the effect of supplemental irrigation (SI on the root growth, soil water variation, and grain yield of winter wheat in this region by measuring the moisture content in different soil layers. Prior to SI, the soil water content (SWC at given soil depths was monitored to calculate amount of irritation water that can rehydrate the soil to target SWC. The SWC before SI was monitored to depths of 20, 40, and 60 cm in treatments of W20, W40, and W60, respectively. Rainfed treatment with no irrigation as the control (W0. The mean root weight density (RWD, triphenyl tetrazolium chloride reduction activity (TTC reduction activity, soluble protein (SP concentrations as well as catalase (CAT, and superoxide dismutase (SOD activities in W40 and W60 treatments were significantly higher than those in W20. The RWD in 60–100 cm soil layers and the root activity, SP concentrations, CAT and SOD activities in 40–60 cm soil layers in W40 treatment were significantly higher than those in W20 and W60. W40 treatment is characterized by higher SWC in the upper soil layers but lower SWC in the 60–100-cm soil layers during grain filling. The soil water consumption (SWU in the 60–100 cm soil layers from anthesis after SI to maturity was the highest in W40. The grain yield, water use efficiency (WUE, and irrigation water productivity were the highest in W40, with corresponding mean values of 9169 kg ha−1, 20.8 kg ha−1 mm−1, and 35.5 kg ha−1 mm−1. The RWD, root activities, SP concentrations, CAT and SOD activities, and SWU were strongly positively correlated with grain yield and WUE. Therefore, the optimum soil layer for SI of winter wheat after jointing is 0–40 cm.

SMALL GRAIN 1, which encodes a mitogen-activated protein kinase kinase 4, influences grain size in rice.

Science.gov (United States)

Duan, Penggen; Rao, Yuchun; Zeng, Dali; Yang, Yaolong; Xu, Ran; Zhang, Baolan; Dong, Guojun; Qian, Qian; Li, Yunhai

2014-02-01

Although grain size is one of the most important components of grain yield, little information is known about the mechanisms that determine final grain size in crops. Here we characterize rice small grain1 (smg1) mutants, which exhibit small and light grains, dense and erect panicles and comparatively slightly shorter plants. The short grain and panicle phenotypes of smg1 mutants are caused by a defect in cell proliferation. The smg1 mutations were identified, using a map-based cloning approach, in mitogen-activated protein kinase kinase 4 (OsMKK4). Relatively higher expression of OsMKK4/SMG1 was detected in younger organs than in older ones, consistent with its role in cell proliferation. Green fluorescent protein (GFP)-OsMKK4/SMG1 fusion proteins appear to be distributed ubiquitously in plant cells. Further results revealed that OsMKK4 influenced brassinosteroid (BR) responses and the expression of BR-related genes. Thus, our findings have identified OsMKK4 as a factor for grain size, and suggest a possible link between the MAPK pathways and BRs in grain growth. © 2013 The Authors The Plant Journal © 2013 John Wiley & Sons Ltd.

Effect of Drought Stress at Pre and Post-anthesis on Dry Matter Accumulation of Grains in Irrigated Winter Wheat

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Sh. Elyasi

2011-01-01

Full Text Available Investigating assimilate contribution and grain filling pattern in winter wheat is importance under drought stress condition. This study was conducted to evaluate the relationship between drought stress on grain filling and yield of 4 cultivars including MV17 (dwarf, Alvand, Shahryar (semi-dwarf and Toos (tall. Experimental design was randomized complete block with three replications. Drought stress assigned to main plots and cultivars to sub plots. Growth curve sampling started at 7 days after anthesis with 4 days interval. In pre-anthesis drought stress Alvand produced highest yield, while it was 29.14% less than control treatment. The yield of Toos cultivar was lowest at pre-anthesis drought stress. Rate of grain filling of Toos cultivar did not change at pre-anthesis drought stress. Drought stress treatment at post-anthesis decreased rate of grain filling in all cultivars as compared to control, but it was significant only Toos c.v. In pre-anthesis drought stress grain filling duration increased in Alvand but decreased in Toos. Alvand with higher rate of grain filling produced highest grain yield (3850 kg/ha. It can be concluded that, drought stress decreases grain filling duration and rate of grain filling.

Increasing Winter Maximal Metabolic Rate Improves Intrawinter Survival in Small Birds.

Science.gov (United States)

Petit, Magali; Clavijo-Baquet, Sabrina; Vézina, François

Small resident bird species living at northern latitudes increase their metabolism in winter, and this is widely assumed to improve their chances of survival. However, the relationship between winter metabolic performance and survival has yet to be demonstrated. Using capture-mark-recapture, we followed a population of free-living black-capped chickadees (Poecile atricapillus) over 3 yr and evaluated their survival probability within and among winters. We also measured the size-independent body mass (M s ), hematocrit (Hct), basal metabolic rate (BMR), and maximal thermogenic capacity (Msum) and investigated how these parameters influenced survival within and among winters. Results showed that survival probability was high and constant both within (0.92) and among (0.96) winters. They also showed that while M s , Hct, and BMR had no significant influence, survival was positively related to Msum-following a sigmoid relationship-within but not among winter. Birds expressing an Msum below 1.26 W (i.e., similar to summer levels) had a winter. Our data therefore suggest that black-capped chickadees that are either too slow or unable to adjust their phenotype from summer to winter have little chances of survival and thus that seasonal upregulation of metabolic performance is highly beneficial. This study is the first to document in an avian system the relationship between thermogenic capacity and winter survival, a proxy of fitness.

Higher Fusarium Toxin Accumulation in Grain of Winter Triticale Lines Inoculated with Fusarium culmorum as Compared with Wheat †

Science.gov (United States)

Góral, Tomasz; Wiśniewska, Halina; Ochodzki, Piotr; Walentyn-Góral, Dorota

2016-01-01

Resistance to Fusarium head blight in 32 winter triticale and 34 winter wheat accessions was evaluated. Triticale and wheat were sown in field experiments in two locations. At the time of flowering, heads were inoculated with three Fusarium culmorum isolates. Fusarium head blight index was scored and after the harvest percentage of Fusarium damaged kernels was assessed. Grain was analysed for type B trichothecenes (deoxynivalenol and derivatives, nivalenol) and zearalenone (ZEN) content. The average Fusarium head blight indexes were 28.0% for wheat and 19.2% for triticale accessions. The percentage of Fusarium damaged kernels was also higher for wheat and came to 55.6%, while for triticale this figure was 40.2%. The average content of deoxynivalenol (DON) for wheat amounted to 11.65 mg/kg and was lower than the result for triticale which was 14.12 mg/kg. The average contents of nivalenol were similar in both cereals: 4.13 mg/kg and 5.19 mg/kg for wheat and triticale respectively. Considerable amounts of DON derivatives in the cereals were also detected. The ZEN content in the grain was 0.60 mg/kg for wheat and 0.66 mg/kg for triticale. Relationships between Fusarium head blight index, Fusarium damaged kernels and mycotoxin contents were statistically significant for wheat and mostly insignificant for triticale. Triticale proved to have less infected heads and kernels than wheat. However, the content of type B trichothecenes was higher in triticale grain than in wheat grain. PMID:27763547

Concentration of radiocaesium in grain following the Chernobyl accident

International Nuclear Information System (INIS)

Kanyar, B.; Czegledi, P.; Kerekes, A.; Kovacs, L.; Sohar, J.; Sztanyik, L.B.

1991-01-01

Radioactivity measurements and dose assessments in Hungary after the Chernobyl accident have shown that the consumption of baker's ware contributes significantly to the internal dose of man. Flour and bread have been contaminated mainly due to radiocaesium deposition onto the of cereals at the end of April and beginning of May, 1986. Because of the different seasonal and growing conditions of biomass, the interception fraction of the standing winter wheat became higher than that of the summer wheat. Therefore, the contribution of grain to the internal dose was relatively high in Hungary where near to 90 per cent of flour and bread is produced from winter wheat in comparison with other countries. The average concentration of 137 Cs in winter grain harvested in summer 1986 was 32 Bq/kg with a range of 11-140 Bq/kg. The bran contained almost half of the total radiocaesium of the grain with about 20 per cent of the weight. The 40 K concentration of grain was 149 Bq/kg. The 137 Cs concentration in white bread commonly used in Hungary was 22 Bq/kg in average. The concentrations found in bread samples from the whole country showed a high variation due to the uneven deposition of radioactive substances. The 137 Cs concentration in winter grain was 0.0075±0.0017 Bq/kg normalized to 1 Bq/m 2 deposition density. The 137 Cs concentration in grain harvested in 1987 or later became less than 1 Bq/kg. It suggests that the root uptake of radiocaesium by cereals must be very small. The per caput committed effective dose equivalent due to consumption of baker's ware was estimated as 50 micro-Sv. (author)

Winter wheat grain yield and its components in the North China Plain: irrigation management, cultivation, and climate

Directory of Open Access Journals (Sweden)

Lihua Lv

2013-09-01

Full Text Available Irrigation has been identified as the main driving factor of groundwater drawdown in the North China Plain (NCP. In order to develop appropriate irrigation strategies for satisfactory yields of wheat (Triticum aestivum L., grain yield (GY, yield components, and water use efficiency (WUE were studied. A field experiment was conducted with two types of winter wheat, 'Shimai15' and 'Shixin733', and five irrigation treatments, including rainfed and four spring irrigation water applications, in four growing seasons (2005 to 2009. Results showed that maximum GY was achieved with three irrigation treatments in the 2005-2006 and 2008-2009 dry seasons and two irrigation treatments in the 2006-2007 normal season. However, in the 2007-2008 wet season, the four irrigation treatments, especially the additional irrigation event at the reviving stage (28, produced maximum GY. Grain yield was significantly related to seasonal full evapotranspiration (ET and 410 to 530 mm of seasonal full ET, including 143 mm rainfall and 214 mm irrigation water, which led to maximum GY. The two types of cultivars responded differently to irrigation management in different rainfall years. The yield of the water-saving cv. 'Shimai 15' was much higher in the dry seasons than in the other seasons. Variations of yield components were mainly caused by irrigation time and meteorological factors. The higher accumulated temperature during the sowing and tillering stages (24 and irrigation or precipitation at the reviving stage (28 significantly improved tiller growth. The lower average temperature in March and April greatly increased grain number per spike. Sunshine duration played a decisive role in improving grain weight. Our results provide very useful information about irrigation time and frequency of winter wheat in the NCP in order to obtain high yield but reduce the use of underground water.

Electrons scattered inside small dust grains of various materials

International Nuclear Information System (INIS)

Richterova, Ivana; Beranek, Martin; Pavlu, Jiri; Nemecek, Zdenek; Safrankova, Jana

2010-01-01

The dust grain charge in an electron beam is given by a difference in numbers of electrons that fall onto the grain and those leaving it. Electrons with energies exceeding 1 keV can penetrate through submicron-sized dust grains. If the grain is small enough, a yield of these electrons reaches unity but they leave a part of their energy inside the grain and this energy excites secondary electrons. The paper presents a hybrid Monte Carlo code that simulates paths of the primary electrons inside a spherical grain and provides the yield of scattered electrons and their energy spectrum as a function of the grain size and material. This code is based on the Richterovaet al. [Phys. Rev. B 74, 235430 (2006)] model but it includes several corrections important for light materials like carbon or ice. The model was verified using experimental results obtained on large planar samples. For spherical samples, we have found that the yield of scattered electrons reaches unity for 50 nm Au grains illuminated by 5 keV electrons, whereas the same effect can be observed on ≅1000 nm carbon grains.

Infrared emission from isolated dust clouds in the presence of very small dust grains

Science.gov (United States)

Lis, Dariusz C.; Leung, Chun M.

1991-01-01

Models of the effects of small grain-generated temperature fluctuations on the IR spectrum and surface brightness of externally heated interstellar dust clouds are presently constructed on the basis of a continuum radiation transport computer code which encompasses the transient heating of small dust grains. The models assume a constant fractional abundance of large and small grains throughout the given cloud. A comparison of model results with IRAS observations indicates that the observed 12-25 micron band emissions are associated with about 10-A radius grains, while the 60-100 micron emission is primarily due to large grains which are heated under the equilibrium conditions.

Climatic warming increases winter wheat yield but reduces grain nitrogen concentration in east China.

Directory of Open Access Journals (Sweden)

Yunlu Tian

Full Text Available Climatic warming is often predicted to reduce wheat yield and grain quality in China. However, direct evidence is still lacking. We conducted a three-year experiment with a Free Air Temperature Increase (FATI facility to examine the responses of winter wheat growth and plant N accumulation to a moderate temperature increase of 1.5°C predicted to prevail by 2050 in East China. Three warming treatments (AW: all-day warming; DW: daytime warming; NW: nighttime warming were applied for an entire growth period. Consistent warming effects on wheat plant were recorded across the experimental years. An increase of ca. 1.5°C in daily, daytime and nighttime mean temperatures shortened the length of pre-anthesis period averagely by 12.7, 8.3 and 10.7 d (P<0.05, respectively, but had no significant impact on the length of the post-anthesis period. Warming did not significantly alter the aboveground biomass production, but the grain yield was 16.3, 18.1 and 19.6% (P<0.05 higher in the AW, DW and NW plots than the non-warmed plot, respectively. Warming also significantly increased plant N uptake and total biomass N accumulation. However, warming significantly reduced grain N concentrations while increased N concentrations in the leaves and stems. Together, our results demonstrate differential impacts of warming on the depositions of grain starch and protein, highlighting the needs to further understand the mechanisms that underlie warming impacts on plant C and N metabolism in wheat.

The effects of irradiation on grain coat color and grain texture in winter wheat

International Nuclear Information System (INIS)

Miao Bingliang; Liu Xueyu

1989-01-01

Dry seeds of the variety ''Yangmai 5'' with red grain coat, semihard grain texture, and the variety ''Ningmai 3'' with red grain coat, soft grain texture were irradiated with Y-rays at various doses.The effect on M1 grain coat color was different between two varieties, the higher doses made grain coat color of ''Yangmai 5'' redder, but had hardly effect on ''Ningmai 3''.The effect on M1 grain texture showed that the grain texture became softer with doses increased.It was found that there were 0.6% of positive ( red to white ) grain coat color mutants and 2.0% of negative(hard to soft) grain texture mutants in M2 of ''Yangmai 5'', and there were 0.7% of negative ( white to red ) grain coat color mutants and 3.6% of positive ( soft to hard ) grain texture mutants in M2 of ''Ningmai 3''. It seemed that the positive mutants selected in M3 were stable in M4. The results showed that γ-rays can be used to improve the grain coat color andgrain texture of wheat varieties

Effects of shading on morphology, physiology and grain yield of winter wheat

DEFF Research Database (Denmark)

Li, Huawei; Jiang, Dong; Wollenweber, Bernd

2010-01-01

In a field experiment, winter wheat (Triticum aestivum L.) cultivars Yangmai 158 (YM 158, shading tolerant) and Yangmai 11 (YM 11, shading-sensitive) were subjected to shading between jointing and maturity. Three shading treatments were applied, i.e. 92% (S1), 85% (S2) and 77% (S3) of full...... the shading treatments applied, leaf area index, length of the peduncle internode, area of the upper leaves and content of pigments increased, which favoured efficient light capture. Shading modified light quality in the canopy as indicated by increases of diffuse- and blue light fractions and a reduction...... the flag leaf, as in most cases Pn of the third and the penultimate leaves were found to increase under shading treatments. Shading increased the redistribution of dry matter from vegetative organs into grains. The responses of the morphological and physiological traits to shading are discussed in relation...

A new component of the interstellar matter - Small grains and large aromatic molecules

International Nuclear Information System (INIS)

Puget, J.L.

1989-01-01

Predictions from dust models constructed to account for the interstellar extinction curve are in conflict with emission data. This paper shows that the introduction of small grains and large aromatic molecules as a new component of the interstellar matter can resolve this conflict. Observational evidence for the existence of very small grains is also reviewed, along with the physics of IR emission by thermal fluctuations and its relation to very small particles. 99 refs

Size and density distribution of very small dust grains in the Barnard 5 cloud

Science.gov (United States)

Lis, Dariusz C.; Leung, Chun Ming

1991-01-01

The effects of the temperature fluctuations in small graphite grains on the energy spectrum and the IR surface brightness of an isolated dust cloud heated externally by the interstellar radiation field were investigated using a series of models based on a radiation transport computer code. This code treats self-consistently the thermal coupling between the transient heating of very small dust grains and the equilibrium heating of conventional large grains. The model results were compared with the IRAS observations of the Barnard 5 (B5) cloud, showing that the 25-micron emission of the cloud must be produced by small grains with a 6-10 A radius, which also contribute about 50 percent to the observed 12-micron emission. The remaining 12 micron flux may be produced by the polycyclic aromatic hydrocarbons. The 60-and 100-micron radiation is dominated by emission from large grains heated under equilibrium conditions.

Capability of crop water content for revealing variability of winter wheat grain yield and soil moisture under limited irrigation.

Science.gov (United States)

Zhang, Chao; Liu, Jiangui; Shang, Jiali; Cai, Huanjie

2018-08-01

Winter wheat (Triticum aestivum L.) is a major crop in the Guanzhong Plain, China. Understanding its water status is important for irrigation planning. A few crop water indicators, such as the leaf equivalent water thickness (EWT: g cm -2 ), leaf water content (LWC: %) and canopy water content (CWC: kg m -2 ), have been estimated using remote sensing techniques for a wide range of crops, yet their suitability and utility for revealing winter wheat growth and soil moisture status have not been well studied. To bridge this knowledge gap, field-scale irrigation experiments were conducted over two consecutive years (2014 and 2015) to investigate relationships of crop water content with soil moisture and grain yield, and to assess the performance of four spectral process methods for retrieving these three crop water indicators. The result revealed that the water indicators were more sensitive to soil moisture variation before the jointing stage. All three water indicators were significantly correlated with soil moisture during the reviving stage, and the correlations were stronger for leaf water indicators than that of the canopy water indicator at the jointing stage. No correlation was observed after the heading stage. All three water indicators showed good capabilities of revealing grain yield variability in jointing stage, with R 2 up to 0.89. CWC had a consistent relationship with grain yield over different growing seasons, but the performances of EWT and LWC were growing-season specific. The partial least squares regression was the most accurate method for estimating LWC (R 2 =0.72; RMSE=3.6%) and comparable capability for EWT and CWC. Finally, the work highlights the usefulness of crop water indicators to assess crop growth, productivity, and soil water status and demonstrates the potential of various spectral processing methods for retrieving crop water contents from canopy reflectance spectrums. Copyright © 2018 Elsevier B.V. All rights reserved.

Analysis of the Determinants of Small-Scale Farmers' Grain Market ...

African Journals Online (AJOL)

In some cases, farmers may sell at low price when they face financial constraints, especially ... Analysis of the Determinants of Small-Scale Farmers' Grain Market Participations. [76] ...... An MSc Thesis Presented to the School of Graduate.

Winter barley mutants created in the Ukraine

International Nuclear Information System (INIS)

Zayats, O.M.

2001-01-01

Full text: Increasing fodder and protein production is one of the objectives of the development of agriculture in Ukraine. Higher productivity of fodder crops, due to new highly productive varieties, is the means to meet this aim. Winter barley is an important crop for fodder purposes. The climate of the Ukraine is favourable for growing this crop. The areas used for the growth of winter barley are however, small (500,000-550,000 ha) and there is a shortage of good quality varieties. The main aim of the work was therefore to create new varieties of highly productive winter barley, of good quality. The new varieties and mutation lines of winter barley were created under the influence of water solutions of N-nitroso-N-methylurea (NMH - 0,012, 0,005%), N-nitroso-N-ethylurea (NEH - 0,05; 0.025; 0,012%) ethyleneimine (EI - 0,02; 0,01; 0,005%) on winter barley seeds of the varieties of local and foreign selections. On the basis of many years of investigations (1984-94) the following mutations were described: hard-grained, winter-hardiness, earliness, middle-maturity, late-maturity, wide and large leaves, narrow leaves, multinodal, great number of leaves, great number of flowers, strong stem (lodging resistant), tallness, semi-dwarfness, dwarfness, and high productivity. Particularly valuable are mutants with high productivity of green bulk. Their potential yield is 70 t/ha. As a result of the work two varieties of winter barley 'Shyrokolysty' and 'Kormovy' were released into the State register of plant varieties of the Ukraine. The other valuable mutant genotypes are used in cross breeding programmes. (author)

Relaxing the Small Particle Approximation for Dust-grain opacities in Carbon-star Wind Models

OpenAIRE

Mattsson, Lars; Höfner, Susanne

2010-01-01

We have computed wind models with time-dependent dust formation and grain-size dependent opacities, where (1) the problem is simplified by assuming a fixed dust-grain size, and where (2) the radiation pressure efficiency is approximated using grain sizes based on various means of the actual grain size distribution. It is shown that in critical cases, the effect of grain sizes can be significant. For well-developed winds, however, the effects on the mass-loss rate and the wind speed are small.

Hard Winter Wheat and Flour Properties in Relation to Breadmaking Quality of Straight-dough Bread: Flour Particle Size and Bread Crumb Grain

Institute of Scientific and Technical Information of China (English)

S H Park; O K Chung; P A Seib

2006-01-01

Samples of 12 hard winter wheats and their flours that produced breads varying in crumb grain scores were studied for 38 quality parameters including: wheat physical and chemical characteristics; flour ash and protein contents, starch damage,swelling power, pasting characteristics, and flour particle size distribution; dough properties determined by a mixograph; and breadmaking properties for pup loaves (100g flour). Only two parameters, the protein content of wheat and the granulation of flour, showed significant correlations with bread crumb grain scores. Protein content of wheat ranging 12.9%～ 14.5% determined by an NIR method showed a weak inverse relationship (r =-0.61, p ＜ 0.05) with bread crumb grain score. Flour particle size distribution measured by both Alpine Air Jet Sieve and NIR methods revealed that the weight wt % of particles less than 38μ m in size and representing 9.6%～ 19.3% of the flour weights was correlated positively (r =0.78, p ＜ 0.01) with crumb grain score, whereas wt % of flour particles larger than 125μm had an inverse relationship (r =-0.60, p＜0.05) with crumb grain score.

The influence of inorganic nitrogen fertilizer forms on micronutrient retranslocation and accumulation in grains of winter wheat.

Science.gov (United States)

Barunawati, Nunun; Giehl, Ricardo F Hettwer; Bauer, Bernhard; von Wirén, Nicolaus

2013-01-01

The fortification of cereal grains with metal micronutrients is a major target to combat human malnutrition of Fe and Zn. Based on recent studies showing that N fertilization can promote Fe and Zn accumulation in cereal grains, we investigated here the influence of nitrate- or ammonium-based N fertilization on the accumulation of Fe, Zn, and Cu as well as metal chelator pools in flag leaves and grains of winter wheat. Fertilization with either N form increased the concentrations of N and of the metal chelator nicotianamine (NA) in green leaves, while 2'-deoxymugineic acid (DMA) remained unaffected. Despite the differential response to N fertilization of NA and DMA levels in flag leaves, N fertilization remained without any significant effect on the net export of these metals during flag leaf senescence, which accounted for approximately one third of the total Fe, Zn, or Cu content in leaves. The significant increase in the accumulation of Fe, Zn, and Cu found in the grains of primarily ammonium-fertilized plants was unrelated to the extent of metal retranslocation from flag leaves. These results indicate that an increased N nutritional status of flag leaves promotes the accumulation of Fe, Zn, and Cu in flag leaves, which is accompanied by an increased pool of NA but not of DMA. With regard to the far higher concentrations of DMA relative to NA in leaves and leaf exudates, DMA may be more relevant for the mobilization and retranslocation of these metals in high-yielding wheat production.

The influence of inorganic nitrogen fertilizer forms on micronutrient retranslocation and accumulation in grains of winter wheat

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Nunun eBarunawati

2013-08-01

Full Text Available The fortification of cereal grains with metal micronutrients is a major target to combat human malnutrition of Fe and Zn. Based on recent studies showing that N fertilization can promote Fe and Zn accumulation in cereal grains, we investigated here the influence of nitrate- or ammonium-based N fertilization on the accumulation of Fe, Zn and Cu as well as metal chelator pools in flag leaves and grains of winter wheat. Fertilization with either N form increased the concentrations of N and of the metal chelator nicotianamine (NA in green leaves, while 2’-deoxymugineic acid (DMA remained unaffected. Despite the differential response to N fertilization of NA and DMA levels in flag leaves, N fertilization remained without any significant effect on the net export of these metals during flag leaf senescence, which accounted for approx. one third of the total Fe, Zn or Cu content in leaves. The significant increase in the accumulation of Fe, Zn and Cu found in the grains of primarily ammonium-fertilized plants was unrelated to the extent of metal retranslocation from flag leaves. These results indicate that an increased N nutritional status of flag leaves promotes the accumulation of Fe, Zn and Cu in flag leaves, which is accompanied by an increased pool of NA but not of DMA. With regard to the far higher concentrations of DMA relative to NA in leaves and leaf exudates, DMA may be more relevant for the mobilization and retranslocation of these metals in high-yielding wheat production.

Exogenous Cytokinins Increase Grain Yield of Winter Wheat Cultivars by Improving Stay-Green Characteristics under Heat Stress.

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Dongqing Yang

Full Text Available Stay-green, a key trait of wheat, can not only increase the yield of wheat but also its resistance to heat stress during active photosynthesis. Cytokinins are the most potent general coordinator between the stay-green trait and senescence. The objectives of the present study were to identify and assess the effects of cytokinins on the photosynthetic organ and heat resistance in wheat. Two winter wheat cultivars, Wennong 6 (a stay-green cultivar and Jimai 20 (a control cultivar, were subjected to heat stress treatment from 1 to 5 days after anthesis (DAA. The two cultivars were sprayed daily with 10 mg L-1 of 6-benzylaminopurine (6-BA between 1 and 3 DAA under ambient and elevated temperature conditions. We found that the heat stress significantly decreased the number of kernels per spike and the grain yield (P < 0.05. Heat stress also decreased the zeatin riboside (ZR content, but increased the gibberellin (GA3, indole-3-acetic acid (IAA, and abscisic acid (ABA contents at 3 to 15 DAA. Application of 6-BA significantly (P < 0.05 increased the grain-filling rate, endosperm cell division rate, endosperm cell number, and 1,000-grain weight under heated condition. 6-BA application increased ZR and IAA contents at 3 to 28 DAA, but decreased GA3 and ABA contents. The contents of ZR, ABA, and IAA in kernels were positively and significantly correlated with the grain-filling rate (P < 0.05, whereas GA3 was counter-productive at 3 to 15 DAA. These results suggest that the decrease in grain yield under heat stress was due to a lower ZR content and a higher GA3 content compared to that at elevated temperature during the early development of the kernels, which resulted in less kernel number and lower grain-filling rate. The results also provide essential information for further utilization of the cytokinin substances in the cultivation of heat-resistant wheat.

Comparison of winter wheat yield sensitivity to climate variables under irrigated and rain-fed conditions

Science.gov (United States)

Xiao, Dengpan; Shen, Yanjun; Zhang, He; Moiwo, Juana P.; Qi, Yongqing; Wang, Rende; Pei, Hongwei; Zhang, Yucui; Shen, Huitao

2016-09-01

Crop simulation models provide alternative, less time-consuming, and cost-effective means of determining the sensitivity of crop yield to climate change. In this study, two dynamic mechanistic models, CERES (Crop Environment Resource Synthesis) and APSIM (Agricultural Production Systems Simulator), were used to simulate the yield of wheat ( Triticum aestivum L.) under well irrigated (CFG) and rain-fed (YY) conditions in relation to different climate variables in the North China Plain (NCP). The study tested winter wheat yield sensitivity to different levels of temperature, radiation, precipitation, and atmospheric carbon dioxide (CO2) concentration under CFG and YY conditions at Luancheng Agro-ecosystem Experimental Stations in the NCP. The results from the CERES and APSIM wheat crop models were largely consistent and suggested that changes in climate variables influenced wheat grain yield in the NCP. There was also significant variation in the sensitivity of winter wheat yield to climate variables under different water (CFG and YY) conditions. While a temperature increase of 2°C was the threshold beyond which temperature negatively influenced wheat yield under CFG, a temperature rise exceeding 1°C decreased winter wheat grain yield under YY. A decrease in solar radiation decreased wheat grain yield under both CFG and YY conditions. Although the sensitivity of winter wheat yield to precipitation was small under the CFG, yield decreased significantly with decreasing precipitation under the rainfed YY treatment. The results also suggest that wheat yield under CFG linearly increased by ≈3.5% per 60 ppm (parts per million) increase in CO2 concentration from 380 to 560 ppm, and yield under YY increased linearly by ≈7.0% for the same increase in CO2 concentration.

Outflow and clogging of shape-anisotropic grains in hoppers with small apertures.

Science.gov (United States)

Ashour, A; Wegner, S; Trittel, T; Börzsönyi, T; Stannarius, R

2017-01-04

Outflow of granular material through a small orifice is a fundamental process in many industrial fields, for example in silo discharge, and in everyday's life. Most experimental studies of the dynamics have been performed so far with monodisperse disks in two-dimensional (2D) hoppers or spherical grains in 3D. We investigate this process for shape-anisotropic grains in 3D hoppers and discuss the role of size and shape parameters on avalanche statistics, clogging states, and mean flow velocities. It is shown that an increasing aspect ratio of the grains leads to lower flow rates and higher clogging probabilities compared to spherical grains. On the other hand, the number of grains forming the clog is larger for elongated grains of comparable volumes, and the long axis of these blocking grains is preferentially aligned towards the center of the orifice. We find a qualitative transition in the hopper discharge behavior for aspect ratios larger than ≈6. At still higher aspect ratios >8-12, the outflowing material leaves long vertical holes in the hopper that penetrate the complete granular bed. This changes the discharge characteristics qualitatively.

Grain Filling Characteristics and Their Relations with Endogenous Hormones in Large- and Small-Grain Mutants of Rice.

Science.gov (United States)

Zhang, Weiyang; Cao, Zhuanqin; Zhou, Qun; Chen, Jing; Xu, Gengwen; Gu, Junfei; Liu, Lijun; Wang, Zhiqin; Yang, Jianchang; Zhang, Hao

2016-01-01

This study determined if the variation in grain filling parameters between two different spikelet types of rice (Oryza sativa L.) is regulated by the hormonal levels in the grains. Two rice mutants, namely, a large-grain mutant (AZU-M) and a small-grain mutant (ZF802-M), and their respective wild types (AZU-WT and ZF802-WT) were grown in the field. The endosperm cell division rate, filling rate, and hormonal levels: zeatin + zeatin riboside (Z+ZR), indo-3-acetic acid (IAA), polyamines (PAs), and abscisic acid (ABA) were determined. The results showed that there was no significant difference between the filling and endosperm cell division rates. These rates were synchronous between the superior and inferior spikelets for both mutants. However, the abovementioned parameters were significantly different between the two spikelet types for the two wild types. The superior spikelets filled faster and their filling rate was higher compared to the inferior ones. Changes in the concentrations of plant hormones were consistent with the observed endosperm cell division rate and the filling rate for both types of spikelets of mutant and wild type plants. Regression analysis showed a significant positive correlation between cell division and filling rates with the concentrations of the investigated hormones. Exogenous chemical application verified the role of ABA, IAA, and PAs in grain filling. The results indicate that poor filling of inferior spikelets in rice occurs primarily due to the reduced hormone concentrations therein, leading to lower division rate of endosperm cells, fewer endosperm cells, slower filling rate, and smaller grain weight.

Grain Filling Characteristics and Their Relations with Endogenous Hormones in Large- and Small-Grain Mutants of Rice.

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Weiyang Zhang

Full Text Available This study determined if the variation in grain filling parameters between two different spikelet types of rice (Oryza sativa L. is regulated by the hormonal levels in the grains. Two rice mutants, namely, a large-grain mutant (AZU-M and a small-grain mutant (ZF802-M, and their respective wild types (AZU-WT and ZF802-WT were grown in the field. The endosperm cell division rate, filling rate, and hormonal levels: zeatin + zeatin riboside (Z+ZR, indo-3-acetic acid (IAA, polyamines (PAs, and abscisic acid (ABA were determined. The results showed that there was no significant difference between the filling and endosperm cell division rates. These rates were synchronous between the superior and inferior spikelets for both mutants. However, the abovementioned parameters were significantly different between the two spikelet types for the two wild types. The superior spikelets filled faster and their filling rate was higher compared to the inferior ones. Changes in the concentrations of plant hormones were consistent with the observed endosperm cell division rate and the filling rate for both types of spikelets of mutant and wild type plants. Regression analysis showed a significant positive correlation between cell division and filling rates with the concentrations of the investigated hormones. Exogenous chemical application verified the role of ABA, IAA, and PAs in grain filling. The results indicate that poor filling of inferior spikelets in rice occurs primarily due to the reduced hormone concentrations therein, leading to lower division rate of endosperm cells, fewer endosperm cells, slower filling rate, and smaller grain weight.

Spatial Variability Analysis of Within-Field Winter Wheat Nitrogen and Grain Quality Using Canopy Fluorescence Sensor Measurements

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Xiaoyu Song

2017-03-01

Full Text Available Wheat grain protein content (GPC is a key component when evaluating wheat nutrition. It is also important to determine wheat GPC before harvest for agricultural and food process enterprises in order to optimize the wheat grading process. Wheat GPC across a field is spatially variable due to the inherent variability of soil properties and position in the landscape. The objectives of this field study were: (i to assess the spatial and temporal variability of wheat nitrogen (N attributes related to the grain quality of winter wheat production through canopy fluorescence sensor measurements; and (ii to examine the influence of spatial variability of soil N and moisture across different growth stages on the wheat grain quality. A geostatistical approach was used to analyze data collected from 110 georeferenced locations. In particular, Ordinary Kriging Analysis (OKA was used to produce maps of wheat GPC, GPC yield, and wheat canopy fluorescence parameters, including simple florescence ratio and Nitrogen Balance Indices (NBI. Soil Nitrate-Nitrogen (NO3-N content and soil Time Domain Reflectometry (TDR value in the study field were also interpolated through the OKA method. The fluorescence parameter maps, soil NO3-N and soil TDR maps obtained from the OKA output were compared with the wheat GPC and GPC yield maps in order to assess their relationships. The results of this study indicate that the NBI spatial variability map in the late stage of wheat growth can be used to distinguish areas that produce higher GPC.

A method of producing small grain Ru intermediate layers for perpendicular magnetic media

International Nuclear Information System (INIS)

Yuan Hua; Qin Yueling; Laughlin, David E.

2008-01-01

NiAl + SiO 2 thin films were used as a grain size reducing seedlayer for cobalt alloy granular perpendicular magnetic recording media. The effect of this NiAl + SiO 2 seedlayer on the microstructure and crystalline orientation of Ru intermediate layer has been investigated. By co-sputtering the composite NiAl + SiO 2 seedlayer, the smallest average grain diameter of NiAl was significantly reduced to about 2.5 nm. The grain size of the subsequent Ru intermediate layer was reduced to about 4 nm. X-ray diffraction results indicate an epitaxial orientation relationship of NiAl (110) // Ru (0002) between the two layers. Moreover, significant improvement of this epitaxial relationship was developed, which produced narrow c-axis distribution of the Ru intermediate layer with small grain size. The addition of the NiAl + SiO 2 seedlayer is a very promising approach to reduce the Ru intermediate layer grain size and eventually the magnetic layer grain size for perpendicular magnetic recording media without deterioration of other properties of thin films

The use of PCR assay for quality testing of grain of winter wheat cultivated in organic, integrated, conventional system and monoculture in phytopathological aspect

Directory of Open Access Journals (Sweden)

Aleksander Łukanowski

2012-12-01

Full Text Available The aim of experiments was to evaluate the occurrence of fungi on grain of winter wheat cv. Roma cultivated in four systems on the experimental fields owned by the Institute of Soil Science and Plant Cultivation. Among pathogenic species, fungi from genus Fusarium dominated. Their number was the lowest on grain harvested in organic system and the highest in integrated one. Saprotrophic species were represented mainly by Alternaria alternata, which occurred the most often in organic system. Determination of F. avenaceum, F. culmorum and F. poae with microscope was confirmed with a PCR assay. All isolates of F. culmorum and F. poae gave an amplification product of Tri 5 gene coding the possibility of trichocene production, while none of isolates of F. avenaceum.

Radiation use efficiency and yield of winter wheat under deficit irrigation in North China

International Nuclear Information System (INIS)

Han, H.; Li, Z.; Ning, T.; Bai, M.; Zhang, X.; Shan, Y.

2008-01-01

An experiment was conducted in North China to investigate the effects of deficit irrigation and winter wheat varieties on the photosynthetic active radiation (PAR) capture ration, PAR utilization and grain yield. Field experiments involved Jimai 20 (J; high yield variety) and Lainong 0153 (L; dryland variety) with non-irrigation and irrigated at the jointing stage. The results showed that whether irrigated at jointing stage or not, there was no significant difference between J and L with respect to the amount of PAR intercepted by the winter wheat canopies. However, significant differences were observed between the varieties with respect to the amount of PAR intercepted by plants that were 60-80 cm above the ground surface. This result was mainly caused by the changes in the vertical distributions of leaf area index. As a result, the effects of the varieties and deficit irrigation on the radiation use efficiency (RUE) and grain yield of winter wheat were due to the vertical distribution of PAR in the winter wheat canopies. During the late growing season of winter wheat, irrespective of the irrigation regime, the RUE and grain yield of J were significantly higher than those of L. These results suggest that a combination of deficit irrigation and a suitable winter wheat variety should be applied in North China

Multiple dislocation pile-ups in small grains at small strains: implications for the Hall-Petch relationship and backstress screening

International Nuclear Information System (INIS)

Schouwenaars, R; Jacobo, V H; Ortiz, A

2014-01-01

A classic explanation for the Hall-Petch relationship is given by the stress field of a single dislocation pile-up perpendicular to the grain boundary. Similarly, the gradual compensation of the stress fields of pile-ups on both sides of the boundary has been invoked to explain the transitory effects observed in the stress- strain curves of ultrafine grained polycrystals. This paper studies the effects of introducing deviations of the highly simplified geometry mentioned above, using the proper mathematical approximations of linear elastic dislocation theory. Multiple pile-ups invalidate the conclusions drawn from the single pile-up model. Pile-ups in multiple grains are assessed by a highly idealised model of an infinite array of periodical pile-ups. In the latter case, screening is always perfect. By considering the Peach-Köhler force between dislocations mutually disoriented grains, the magnitude of the fluctuations around such ideal case can be estimated. However, using sound probabilistic arguments to calculate the free path for dislocation slip in fine-grained polycrystals, it is found that the amount of dislocations that can be stored in the pile- ups is generally too small to explain the strong grain size effects observed experimentally

The nuclear winter

International Nuclear Information System (INIS)

Velikhow, Y.P.

1986-01-01

Nuclear winter is an example of possible secondary effects, and if we speak of secondary we are thinking of small-scale second-order effects, but a nuclear winter is not a second-order effect. If you calculate the amount of heat produced by a nuclear explosion, it is a very small amount which does not have any chance of changing the Earth's climate, but a nuclear explosion drives or stars some new mechanism - the mechanism of nuclear winter - after 100 megatons of dust are transferred to the upper atmosphere. Another example of such amplification is radioactive fall-out, especially long-life radioactive fall-out after the possible elimination of the nuclear power industry, nuclear storage and distribution of storage waste around the globe. This is a very powerful amplification mechanism

Grain Yield and Water Use Efficiency in Extremely-Late Sown Winter Wheat Cultivars under Two Irrigation Regimes in the North China Plain.

Directory of Open Access Journals (Sweden)

Bin Wang

Full Text Available Wheat production is threatened by water shortages and groundwater over-draft in the North China Plain (NCP. In recent years, winter wheat has been increasingly sown extremely late in early to mid-November after harvesting cotton or pepper. To improve water use efficiency (WUE and guide the extremely late sowing practices, a 3-year field experiment was conducted under two irrigation regimes (W1, one-irrigation, 75 mm at jointing; W2, two-irrigation, 75 mm at jointing and 75 mm at anthesis in 3 cultivars differing in spike size (HS4399, small spike; JM22, medium spike; WM8, large spike. Wheat was sown in early to mid-November at a high seeding rate of 800-850 seeds m(-2. Average yields of 7.42 t ha(-1 and WUE of 1.84 kg m(-3 were achieved with an average seasonal evapotranspiration (ET of 404 mm. Compared with W2, wheat under W1 did not have yield penalty in 2 of 3 years, and had 7.9% lower seasonal ET and 7.5% higher WUE. The higher WUE and stable yield under W1 was associated with higher 1000-grain weight (TGW and harvest index (HI. Among the 3 cultivars, JM22 had 5.9%-8.9% higher yield and 4.2%-9.3% higher WUE than WM8 and HS4399. The higher yield in JM22 was attributed mainly to higher HI and TGW due to increased post-anthesis biomass and deeper seasonal soil water extraction. In conclusion, one-irrigation with a medium-sized spike cultivar JM22 could be a useful strategy to maintain yield and high WUE in extremely late-sown winter wheat at a high seeding rate in the NCP.

Yantarnaya is a new variety of fodder winter rye

Directory of Open Access Journals (Sweden)

Bezgodov A.V.

2017-11-01

Full Text Available the article has evaluation of four years observation of the prospective varieties of winter rye Yantarnaya in comparison with the standard in the nursery of the competitive variety trial of the Ural Scientific Research Institute for Agriculture in Yekaterinburg and the results of a two year test in the system of FGBU «Gossortkomissiya». A winter rye is widely used for bread baking mainly. This culture has resistance from negative environmental factors. The main cause of limited use of a winter rye grain for forage is high content water-soluble pentosans over 1.5%. They reduce availability of nutrients to an organism. Creation of varieties with low content of water-soluble pentosans is the rational solution of increase in use of parts of grain of a winter rye in forage production. Together with VIR, a variety with the required characteristics was transferred to the state grade testing. The observation took place in 2013–2017, with contrasts on the weather conditions. According to FGBU «Gossorgkomissiya», the variety has high potential productivity and significantly exceeds same low pentosan variety in the yield.

Assessing the Impact of Air Pollution on Grain Yield of Winter Wheat - A Case Study in the North China Plain

Science.gov (United States)

Zhang, Xiying; Shao, Liwei; Chen, Suying

2016-01-01

The major wheat production region of China the North China Plain (NCP) is seriously affected by air pollution. In this study, yield of winter wheat (Triticum aestivum L.) was analyzed with respect to the potential impact of air pollution index under conditions of optimal crop management in the NCP from 2001 to 2012. Results showed that air pollution was especially serious at the early phase of winter wheat growth significantly influencing various weather factors. However, no significant correlations were found between final grain yield and the weather factors during the early growth phase. In contrast, significant correlations were found between grain yield and total solar radiation gap, sunshine hour gap, diurnal temperature range and relative humidity during the late growing phase. To disentangle the confounding effects of various weather factors, and test the isolated effect of air pollution induced changes in incoming global solar radiation on yield under ceteris paribus conditions, crop model based scenario-analysis was conducted. The simulation results of the calibrated Agricultural Production Systems Simulator (APSIM) model indicated that a reduction in radiation by 10% might cause a yield reduction by more than 10%. Increasing incident radiation by 10% would lead to yield increases of (only) 7%, with the effects being much stronger during the late growing phase compared to the early growing phase. However, there is evidence that APSIM overestimates the effect of air pollution induced changes on radiation, as it does not consider the changes in radiative properties of solar insulation, i.e. the relative increase of diffuse over direct radiation, which may partly alleviate the negative effects of reduced total radiation by air pollution. Concluding, the present study could not detect a significantly negative effect of air pollution on wheat yields in the NCP. PMID:27612146

Assessing the Impact of Air Pollution on Grain Yield of Winter Wheat - A Case Study in the North China Plain.

Directory of Open Access Journals (Sweden)

Xiuwei Liu

Full Text Available The major wheat production region of China the North China Plain (NCP is seriously affected by air pollution. In this study, yield of winter wheat (Triticum aestivum L. was analyzed with respect to the potential impact of air pollution index under conditions of optimal crop management in the NCP from 2001 to 2012. Results showed that air pollution was especially serious at the early phase of winter wheat growth significantly influencing various weather factors. However, no significant correlations were found between final grain yield and the weather factors during the early growth phase. In contrast, significant correlations were found between grain yield and total solar radiation gap, sunshine hour gap, diurnal temperature range and relative humidity during the late growing phase. To disentangle the confounding effects of various weather factors, and test the isolated effect of air pollution induced changes in incoming global solar radiation on yield under ceteris paribus conditions, crop model based scenario-analysis was conducted. The simulation results of the calibrated Agricultural Production Systems Simulator (APSIM model indicated that a reduction in radiation by 10% might cause a yield reduction by more than 10%. Increasing incident radiation by 10% would lead to yield increases of (only 7%, with the effects being much stronger during the late growing phase compared to the early growing phase. However, there is evidence that APSIM overestimates the effect of air pollution induced changes on radiation, as it does not consider the changes in radiative properties of solar insulation, i.e. the relative increase of diffuse over direct radiation, which may partly alleviate the negative effects of reduced total radiation by air pollution. Concluding, the present study could not detect a significantly negative effect of air pollution on wheat yields in the NCP.

Assessing the Impact of Air Pollution on Grain Yield of Winter Wheat - A Case Study in the North China Plain.

Science.gov (United States)

Liu, Xiuwei; Sun, Hongyong; Feike, Til; Zhang, Xiying; Shao, Liwei; Chen, Suying

2016-01-01

The major wheat production region of China the North China Plain (NCP) is seriously affected by air pollution. In this study, yield of winter wheat (Triticum aestivum L.) was analyzed with respect to the potential impact of air pollution index under conditions of optimal crop management in the NCP from 2001 to 2012. Results showed that air pollution was especially serious at the early phase of winter wheat growth significantly influencing various weather factors. However, no significant correlations were found between final grain yield and the weather factors during the early growth phase. In contrast, significant correlations were found between grain yield and total solar radiation gap, sunshine hour gap, diurnal temperature range and relative humidity during the late growing phase. To disentangle the confounding effects of various weather factors, and test the isolated effect of air pollution induced changes in incoming global solar radiation on yield under ceteris paribus conditions, crop model based scenario-analysis was conducted. The simulation results of the calibrated Agricultural Production Systems Simulator (APSIM) model indicated that a reduction in radiation by 10% might cause a yield reduction by more than 10%. Increasing incident radiation by 10% would lead to yield increases of (only) 7%, with the effects being much stronger during the late growing phase compared to the early growing phase. However, there is evidence that APSIM overestimates the effect of air pollution induced changes on radiation, as it does not consider the changes in radiative properties of solar insulation, i.e. the relative increase of diffuse over direct radiation, which may partly alleviate the negative effects of reduced total radiation by air pollution. Concluding, the present study could not detect a significantly negative effect of air pollution on wheat yields in the NCP.

Comparison of wet brewers' grains or dried distillers' grains as supplements to conserved bermudagrass forage as winter feeding options for beef cows.

Science.gov (United States)

Thomas, M V; Hersom, M J; Thrift, T A; Yelich, J V

2017-01-01

The objective of this study was to examine the use of 2 byproduct supplements and conserved warm-season forage as winter feeding options for primiparous beef cows. Gestating Angus ( = 48) and Brangus ( = 24) 2-yr-old cows were stratified by BW and breed to 1 of 12 pens. Pens were randomly assigned 1 of 2 supplements, wet brewers' grains (WBG) or dried distillers' grains (DDG). Coastal bermudagrass hay or round bale silage (RBS) was fed free choice (6 pens each) and cows received WBG or DDG supplements at a daily rate of 0.05% BW (DM basis) prorated for feeding 3 d/wk. Total BW and BCS changes did not differ ( = 0.65 and = 0.93, respectively) between DDG- and WBG-supplemented cows. Total amount of forage DM offered and mean calculated daily forage DM offered did not differ ( = 0.59 and = 0.20, respectively) between supplement treatments. Estimated daily mean and total supplement DM offered was greater ( forage sources were used in an unbalanced 6 × 4 design to measure intake, digestibility, and rumen parameters in ruminally fistulated steers. Supplement did not affect forage DMI of hay ( = 0.31) or RBS ( = 0.63). Total DMI was not different ( = 0.37 and = 0.73) for hay-based and RBS-based diets, respectively. Total tract digestibility tended to be greater ( = 0.06) for DDG than for WBG in hay diets but was not different ( = 0.76) for RBS diets. Daily mean ruminal pH was greater ( = 0.03) for WBG than for DDG when supplemented to hay-based diets. In RBS diets, a supplement × hour interaction ( = 0.05) existed for ruminal pH. Daily mean ruminal ammonia N concentration was greater ( forage. High-moisture forage sources can be coupled with high-moisture byproduct supplements.

Colour characteristics of winter wheat grits of different grain size

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Horváth Zs. H.

2015-01-01

Full Text Available Nowadays, wheat has spread all over the world due to its extensive usability. The colour of wheat grits is very important for the milling and baking industry because it determines the colour of the products made from it. The instrumental colour measuring is used, first of all, for durum wheat. We investigated the relationship between colour characteristics and grain size in the case of different hard aestivum wheats. We determined the colour using the CIE (Commission Internationale de l’Eclairage 1976 L*, a*, b* colour system measured by MINOLTA CR-300 tristimulus colorimeter. After screening the colour of the wheat fractions of different grain size, grits was measured wet and dry. We determined the L*, a*, b* colour co-ordinates and the whiteness index, too. To evaluate the values we had obtained, we used analysis of variance and regression analysis. We pointed out that the colour of wheat grits of different grain size is dependent on the hardness index of wheat. The lightness co-ordinate (L* of grits of the harder wheat is smaller, while a* and b* co-ordinates are higher. We also found that while grain size rises, the L* co-ordinate decreases and a*, b* values increase in the case of every type of wheat. The colour of grits is determined by the colour of fractions of 250-400 μm in size, independently from the average grain size. The whiteness index and the L* colour co-ordinate have a linear relation (R2 = 0.9151; so, the determination of whiteness index is not necessary. The L* value right characterizes the whiteness of grits.

Mass photosynthesis and distribution of photo assimilates of winter wheat varieties with different maturity feature

International Nuclear Information System (INIS)

Wang Fahong; Zhao Junshi

1996-01-01

The mass photosynthesis rate and distribution of photoassimilates of winter wheat varieties with different maturity feature were studied using GXH-305 portable CO 2 infrared ray analyzer. The mass photosynthesis rate of winter wheat varieties with better maturity feature showed little difference from the varieties with general maturity feature during the early stage of grain filling phase. However, the mass photosynthesis rate of the former was significantly higher than that of the later during the middle and late stage of grain filling. The study with 14 CO 2 -tracing method showed that the relative activity in different organs of varieties with better maturity feature was significantly higher than that of varieties with worse maturity feature during the later growth stage of winter wheat. The rate of photoassimilates distribution in stalk and root system of winter wheat varieties with better maturity was higher than that in the others organs. The physiological mechanism of difference of grain yield and plant decay in varieties with different maturity feature were also discussed

NEW GENOTYPES AND TECHNOLOGICAL INDICATORS OF WINTER TRITICALE

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T. Z.

2016-02-01

Full Text Available The aim of the research was to conduct basic screening of new lines and cultivars of winter hexaploid triticale by the technological and molecular genetics indicators. Molecular and genetic research conducted by polymerase chain reaction allelic variants of gene loci Wx-A1, Wx-B1, and quality parameters of grain, flour and bread – on technological markers. The new cultivars and lines of winter hexaploid triticale of Nosivka Breeding and Research Station of Remeslo Myronivka Institute of Wheat by technological indicators of grain, flour and bread quality were studied. According to representative criteria’s the most promising genotypes, which are the main products in terms Forest-Steppe ecotypes’ and a high-quality raw materials for bakeries and bioethanol were identified. Molecular and genetic identifications of allelic variants of genes loci Wx-A1, Wx-B1 triticale, which in the early stages of ontogenesis to predict targeted uses genotypes were conducted. The first among a series of triticale cultivars and lines Forest-Steppe ecotypes and biotypes with nonfunctional b gene allele WxA1, which defines a high content of amylopectin of starch, an important release for more ethanol was identified. It was found that technological characteristics of grain, flour and bread of new cultivars and lines of winter triticale meet the modern requirements production dietetic food and bioenergy products is important and relevant in the context of food security of Ukraine.

The future of grain science: the contribution of indigenous small grains to food security, nutrition and health in South Africa [AACCI Report

CSIR Research Space (South Africa)

Dlamini, N

2015-08-01

Full Text Available slower release of glucose into the bloodstream, which is an important aspect for the management of diabetes. Despite their potential nutritional and health benefits, production of commercially grown small grain crops is not significant in South Africa...

Impact of Early Sowing on Winter Wheat Receiving Manure or Mineral Fertilizers

DEFF Research Database (Denmark)

Christensen, Bent Tolstrup; Jensen, Johannes Lund; Thomsen, Ingrid Kaag

2017-01-01

(late September) wheat were tested over two cropping seasons (2011–2012 and 2013–2014) using two contemporary cultivars (Hereford and Mariboss) and increasing rates of N (0–300 kg total N ha–1) with animal manure (AM; cattle slurry) or mineral fertilizers (NPK), surface applied in late March. We....... Early sowing increased grain yields by 0.5 and 1.0 Mg ha–1 for NPK and AM, respectively, regardless of N rate. Grain and straw N concentrations were higher with NPK than with AM, and NPK showed higher N use efficiency (0.48–0.53) than AM (0.15–0.22). Moving sowing of winter wheat from late September...... to late August provided higher grain and straw yields; the increased over-winter N uptake suggests that the beneficial effect of earlier sowing may surpass that of a catch crop. Cattle slurry surface applied in late March gave poor N use efficiency and low grain protein content....

Tocotrienols and tocopherols in colored-grain wheat, tritordeum and barley.

Science.gov (United States)

Lachman, Jaromír; Hejtmánková, Alena; Orsák, Matyáš; Popov, Marek; Martinek, Petr

2018-02-01

Colored-grain spring and winter wheat, spring tritordeum and barley (blue aleurone, purple pericarp, and yellow endosperm) from the harvests 2014 and 2015 were evaluated for tocol contents by HPLC-FD. Higher content of total tocols was found in spring wheat varieties compared with winter varieties. Four tocols (β-tocotrienol, α-tocotrienol, β-tocopherol, and α-tocopherol) were identified in wheat and tritordeum varieties. Dominant tocols in purple- and blue-grained wheat and yellow-grained tritordeum were α-tocopherol and β-tocotrienol, whereas spring barley varieties differed from wheat and tritordeum by high α-tocotrienol content. Tocol content was significantly affected by genotype and in a lesser extent in some varieties and lines also by rainfall and temperatures during crop year. Higher rainfall and lower temperatures caused in most varieties higher tocol contents. Purple- and blue-grained wheat lines with higher tocol, anthocyanin and phenolic acids with health benefits may be useful for breeding new varieties. Copyright © 2017 Elsevier Ltd. All rights reserved.

Sustainable use of winter Durum wheat landraces under ...

African Journals Online (AJOL)

... the two checks cultivars. Bi- plot analysis showed that some promising lines with reasonable grain yields, good quality parameters, winter hardiness and drought tolerances among yellow rust resistance durum wheat landraces can be selected for semiarid conditions of Mediterranean countries for sustainable production.

Winter cereal yields as affected by animal manure and green manure in organic arable farming

DEFF Research Database (Denmark)

Olesen, Jørgen E; Askegaard, Margrethe; Rasmussen, Ilse Ankjær

2009-01-01

The effect of nitrogen (N) supply through animal and green manures on grain yield of winter wheat and winter rye was investigated from 1997 to 2004 in an organic farming crop rotation experiment in Denmark on three different soil types varying from coarse sand to sandy loam. Two experimental....... Adjusting for these model-estimated side-effects resulted in wheat grain yields gains from manure application of 0.7-1.1 Mg DM ha-1. The apparent recovery efficiency of N in grains (N use efficiency, NUE) from NH4-N in applied manure varied from 23% to 44%. The NUE in the winter cereals of N accumulated......-estimated benefit of increasing N input in grass-clover from 100 to 500 kg N ha-1 varied from 0.8 to 2.0 Mg DM ha-1 between locations. This is a considerably smaller yield increase than obtained for manure application, and it suggests that the productivity in this system may be improved by removing the cuttings...

Winter reduction in body mass in a very small, nonhibernating mammal: consequences for heat loss and metabolic rates.

Science.gov (United States)

Taylor, Jan R E; Rychlik, Leszek; Churchfield, Sara

2013-01-01

Low temperatures in northern winters are energetically challenging for mammals, and a special energetic burden is expected for diminutive species like shrews, which are among the smallest of mammals. Surprisingly, shrews shrink their body size in winter and reduce body and brain mass, an effect known as Dehnel's phenomenon, which is suggested to lower absolute energy intake requirements and thereby enhance survival when food availability is low. Yet reduced body size coupled with higher body-surface-to-mass ratio in these tiny mammals may result in thermoregulatory heat production at a given temperature constituting a larger proportion of the total energy expenditure. To evaluate energetic consequences of reduced body size in winter, we investigated common shrews Sorex araneus in northeastern Poland. Average body mass decreased by 19.0% from summer to winter, and mean skull depth decreased by 13.1%. There was no difference in Dehnel's phenomenon between years despite different weather conditions. The whole-animal thermal conductance (proportional to absolute heat loss) in shrews was 19% lower in winter than in summer; the difference between the two seasons remained significant after correcting for body mass and was caused by improved fur insulation in winter. Thermogenic capacity of shrews, although much enhanced in winter, did not reach its full potential of increase, and this corresponded with relatively mild subnivean temperatures. These findings indicate that, despite their small body size, shrews effectively decrease their costs of thermoregulation. The recorded decrease in body mass from summer to winter resulted in a reduction of overall resting metabolic rate (in thermoneutrality) by 18%. This, combined with the reduced heat loss, should translate to food requirements that are substantially lower than would be the case if shrews did not undergo seasonal decrease in body mass.

Predicting the yield and quality of winter wheat grown on calcareous chernozem in the lower Don Region

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Olga Biryukova

2015-07-01

Full Text Available Long-term studies have revealed a system of indicators for predicting the yield of winter wheat grown on a calcareous chernozem. It has been established that the prediction and integrated assessment of the yield and quality of grain should be performed with consideration for the balance of macro- and micronutrients in the grain and the above-ground biomass of plants. It has been shown that the contents of protein and gluten in winter wheat grain are mainly determined by the supply of plants with nitrogen and its balance with Mn, Р, Fe, Zn, and K. Possibility of predicting the contents of macro- and micronutrients in wheat grain from the chemical composition of plants at the shooting stage has been revealed.

Comparison of single-grain and small-aliquot OSL dose estimates in <3000 years old river sediments from South India

International Nuclear Information System (INIS)

Thomas, P.J.; Jain, M.; Juyal, N.; Singhvi, A.K.

2005-01-01

We report on OSL dose distributions derived from small-aliquot and single grains of quartz in young fluvial sediments sampled from the Penner River basin, South India. The single-grain dose distributions suggest that 13 out of 19 samples were well bleached. In many well-bleached samples, there was an underestimation in the single-aliquot dose estimates as compared to those from the single grain-the difference between average dose estimates determined by the two methods ranged from ∼1% to 31%. Such a dose underestimation was not detectable in poorly bleached samples. Various possible reasons for the discrepancy between single-grain and small-aliquot dose estimates are discussed. Although there is no satisfactory explanation for this discrepancy, we speculate that the difference in the stimulation wavelengths, 470+/-30nm in the case of single-aliquot and 532nm in the case of single grains, could perhaps be one of the reasons; this may occur because the stimulation wavelength affects the proportion of the medium and slow components in the initial signal

Comparison of single-grain and small-aliquot OSL dose estimates in < 3000 years old river sediments from South India

DEFF Research Database (Denmark)

Thomas, P.J.; Jain, M.; Juyal, N.

2005-01-01

We report on OSL dose distributions derived from small-aliquot and single grains of quartz in young fluvial sediments sampled from the Penner River basin, South India. The single-grain dose distributions suggest that 13 out of 19 samples were well bleached. In many well-bleached samples, there wa......We report on OSL dose distributions derived from small-aliquot and single grains of quartz in young fluvial sediments sampled from the Penner River basin, South India. The single-grain dose distributions suggest that 13 out of 19 samples were well bleached. In many well-bleached samples......, there was an underestimation in the single-aliquot dose estimates as compared to those from the single grain-the difference between average dose estimates determined by the two methods ranged from similar to 1% to 31%. Such a dose underestimation was not detectable in poorly bleached samples. Various possible reasons...... perhaps be one of the reasons; this may occur because the stimulation wavelength affects the proportion of the medium and slow components in the initial signal. (c) 2004 Elsevier Ltd. All rights reserved....

Eat fresh vegetables, fruit, and whole grain products | NIH MedlinePlus the Magazine

Science.gov (United States)

... please turn Javascript on. Feature: Diverticulitis "Eat fresh vegetables, fruit, and whole grain products." Past Issues / Winter 2010 ... or the diverticulitis. I once again eat fresh vegetables and fruit and whole grain products. My two episodes of ...

Winter diet and food selection of the Black-necked Crane Grus nigricollis in Dashanbao, Yunnan, China

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Hao Yan Dong

2016-04-01

Full Text Available The Black-necked Crane Grus nigricollis is a globally vulnerable species whose food is the factor determining its long-term survival. Understanding dietary habits, food preferences, and related factors will facilitate the development of effective conservation plans for the protection of this vulnerable species. For this purpose, we used video recordings and sampling of food availability to examine the dietary composition and temporal variation in food selection of Black-necked Cranes wintering in the Dashanbao National Nature Reserve, China. The Black-necked Crane’s diet consists primarily of domestic food crops such as grains (74% and potatoes (8%, in addition to invertebrates (14%. A much smaller proportion of the diet was comprised of turnips and wild herbaceous plants and tubers. There was monthly variation in food selection, partially related to food availability. Grains were most available in November and decreased through the winter, whereas invertebrates were more available in November and February than in December and January. Grain consumption was lowest in November but higher from December through February. Invertebrate consumption was highest in November and February. The cranes preferred to eat grains throughout winter months, while they mainly selected invertebrates in November and February. We suggested invertebrate populations sharply declined in December and January due to the low temperature. In addition, grain consumption was negatively associated with invertebrate availability. In November, when invertebrates were most abundant, and despite a concomitant peak in grain abundance, we suggested cranes exhibited a preference for invertebrates over grains. We recommend that the protection administration provide appropriate supplemental foods for cranes during freezing weather.

Performance of organic grain legumes in Tuscany

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Valentina Moschini

2014-03-01

Full Text Available In 2005-2007 growing season, few varieties of field bean, high protein pea and white lupin were compared in an organic farm of Central Italy (Mugello area, Tuscany, to evaluate their agronomic performance in terms of grain yield, nutritional quality and competitive ability against weeds. The experiment was performed under rain-fed conditions. Furthermore, grain legumes features were compared between two different sowing seasons (autumnal vs late-winter for two years, in order to get information on the best time of sowing of these species, and the stability of yields of different genotypes in those climatic and soil conditions. These legumes could be an alternative protein source to external soybean, a high-risk alimentary source of genetically modified organisms, in the organic livestock sector. The main findings indicate that higher yields in grain and crude protein were obtained with the pea species and in particular with cultivars Hardy (4.0 t/ha grain yield; 626 kg/ha crude protein yield and Classic (3.1 t/ha grain yield; 557 kg/ha crude protein yield; followed by field bean cv. Chiaro di Torre Lama (2.9 t/ha grain yield; 624 kg/ha crude protein yield and cv. Vesuvio (2.5 t/ha grain yield; 549 kg/ha crude protein yield. Furthermore the field bean is interesting for the stability of yield in both years despite climatic conditions rather different. The white lupin has showed the lower yield but the best values of grain quality, with higher values in lupin Multitalia for dry matter, crude protein and ether extract and in lupin Luxe also for crude fibre, respect to the other legumes analysed. Among lupin varieties, lupin Multitalia showed the best yield results for the pedo-climatic conditions of Mugello area (0.9 t/ha lupin Multitalia; 0.2 t/ha lupin Luxe. The total yield of organic grain legumes, in the experimental site, is resulted higher with an autumnal seeding respect to the late-winter seeding (2.8 t/ha vs 1.9 t/ha.

Mechanism of secondary recrystallization of Goss grains in grain-oriented electrical steel

Science.gov (United States)

Hayakawa, Yasuyuki

2017-12-01

Since its invention by Goss in 1934, grain-oriented (GO) electrical steel has been widely used as a core material in transformers. GO exhibits a grain size of over several millimeters attained by secondary recrystallization during high-temperature final batch annealing. In addition to the unusually large grain size, the crystal direction in the rolling direction is aligned with , which is the easy magnetization axis of α-iron. Secondary recrystallization is the phenomenon in which a certain very small number of {110} (Goss) grains grow selectively (about one in 106 primary grains) at the expense of many other primary recrystallized grains. The question of why the Goss orientation is exclusively selected during secondary recrystallization has long been a main research subject in this field. The general criterion for secondary recrystallization is a small and uniform primary grain size, which is achieved through the inhibition of normal grain growth by fine precipitates called inhibitors. This paper describes several conceivable mechanisms of secondary recrystallization of Goss grains mainly based on the selective growth model.

DIFFERENCES BETWEEN WHEAT CULTIVARS IN GRAIN PARAMETERS RELATED TO ETHANOL PRODUCTION

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Daniela Mikulíková

2011-12-01

Full Text Available Wheat grain samples from sixteen winter cultivars originated from four localities were evaluated and compared in traits related to ethanol production as grain yield, grain hardness, content of protein, starch and amylose, and α-amylase activity. Results obtained indicate significant differences between cultivars in amylose content, α-amylase activity, and grain hardness compared to grain yield, protein content, and starch content where differences were not significant. The amylose content, α-amylase activity, and grain hardness were affected by cultivar. Both testing methods for starch fermentation - separated hydrolysis and fermentation (SHF and simultaneous saccharification and fermentation (SSF revealed difference between cultivars in ethanol yield.

Autumn-winter diet of three carnivores, European mink (Mustela lutreola, Eurasian otter (Lutra lutra and small-spotted genet (Genetta genetta, in northern Spain

Directory of Open Access Journals (Sweden)

Palazón, S.

2008-12-01

Full Text Available This study describes the autumn-winter diet of three carnivores (Mustela lutreola, Lutra lutra and Genetta genetta in northern Spain. Diet composition was analysed from 85 European mink, 156 otter and 564 spotted genet fecal samples The European mink diet was based on small mammals (relative frequency of occurrences 38.1%, fish (30.9% and birds (16.7%. Spotted genet consumed mainly small mammals, birds and fruits, whilst otter predated practically only fish (95%. Using Levins’ index, trophic-niche widths in European mink, small-spotted genet and Eurasian otter were 3.76, 3.77 and 1.10, respectively. The trophic niche overlap by Pianka index for autumn-winter was 0.77 for European mink vs. Small-spotted genet, and 0.60 for European mink vs. otter. The average size of brown trout taken by otter was larger than those consumed by European mink.

Ecological and Geographical Selection of Winter Wheat (Triticum aestivum L. in Kazakhstan and Kyrgyzstan

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Р. А. Уразалієв

2009-10-01

Full Text Available As a result of the lead long-term selection works wint involving a World' s collection and intertype and intertype hybridization with purposeful selection on economic-biological attributes highly productive • grades of a winter wheat, with stability to various kinds of illnesses and high technological qualities of grain have been allocated. The adapted grades of a winter wheat for a various environment of various zones of the countries of the Central Asia that allows to realize potential opportunities of grades in different environments of cultivation and by that to prevent losses of a crop from biotic and abiotic stresses that allows to stabilize productivity and adaptability of culture in a zon winter husbandry are created. The long-term field experiences lead by us and laboratory analyses on a level of productivity, qualities of grain and stability to stresses allows to conclude, that alongside with a genotype, stabilityenvironmental conditions render strong and significant influence on all complex of selection attributes.

Influência de cortes similando pastejo na composição química de grãos de cereais de inverno Cut effects simulating grazing on the chemical composition of grains of winter cereals

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Leo de Jesus Antunes Del Duca

1999-09-01

Full Text Available A demanda crescente pela integração lavoura-pecuária no planalto sul-rio-grandense direciona ao aproveitamento dos cereais de inverno para duplo propósito (forragem e grão. Assim, é necessário um melhor conhecimento dessas culturas relativamente à utilização como forragem e ao valor econômico dos grãos no uso potencial para alimentação humana ou animal. O objetivo deste estudo foi avaliar a influência de cortes (um e dois, simulando pastejo bovino, na composição química dos grãos de aveia-branca (UPF 14, de aveia-preta (comum, de centeio (BR 1, de triticale (BR 4, de cevada (BR 2 e de trigo (IPF 55204 e PF 87451. Os cortes não afetaram, na média dos cereais, os valores de fibra bruta, de extrato etéreo, de energia bruta e de atividade ureática, tendo o teor de matéria mineral aumentado com dois cortes. Excetuando aveia-preta e cevada, com os cortes verificou-se incremento nos percentuais de proteína bruta. Entretanto, observou-se, na média dos cereais, redução com os cortes nos teores de extrativos não-nitrogenados. Os resultados obtidos conduzem à possibilidade de uso dos cereais de inverno para duplo propósito, com aproveitamento dos grãos sem maiores prejuízos à sua composição química.An increased demand for activities integrating crop-cattle production in the Rio Grande do Sul plateau has contributed to a dual purpose use (forage and grain of winter small grains. Therefore, a better knowledge on how to use these cereals for pasture, as well as on the economic value of grains and their potential use in human and animal foods, is necessary. The objective of this study was to evaluate the influence of cuts (one and two simulating cattle grazing in the chemical composition of the grain of white oats (UPF 14, black oats Avena strigosa (comum, rye (BR 1, triticale (BR 4, barley (BR 2, and wheat (IPF 55204 and PF 87451. In the cereal average, cuts did not affect the values of crude fiber, fat, crude energy, and

Effect of Planting Date on Cold Tolerance of Winter and Spring Barley Genotypes

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A. R. Eivazi

2015-01-01

Full Text Available In order to evaluate cold tolerance of twenty barley genotypes under field conditions, an experiment was carried out in a randomized complete block design at 3 sowing dates of October 5, November 5, and December 5 in Saatlu Agricultural Research Station, West Azarbaijan, Iran, during 2010-11 seasons. Also, another experiment was conducted on the same genotypes based on a completely randomized design under greenhouse conditions. in wich Cold stress was applied up to -25°C at two, four and six leaf development stages. LT50, ion leakage and dry matter were measured and apex photographed. Field experiment results showed the lowest significant differences at p≤0.05 between different levels of sowing date, genotype, and interaction between them for plant height, spike/m2, kernel per spike, 1000-kernel weight, grain yield and total dry matter. Genotypes of winter growth type had higher grain yield (4250kg/ha than those with spring growth type (4190kg/ha. There were significant differences for ion leakage and dry matter at 4 and 6 leaf development stages under greenhouse conditions. Genotype 1 (winter growth type with lowest values of range and standard deviation for grain yield, total dry matter and LT50 = -38 °C showed a relatively low ion leakage. In contrast, genotypes 5, 10 and 14 (spring growth type were identified sensitive to cold stress due to having more values of range, standard deviation for grain yield and total dry matter, LT50 = -18 to -27 °C and ion leakage from 25 to 33µS/m. Regression analysis showed 1000-kernel weight and total dry matter to remain at final model. Cluster analysis indicated that genotypes 2, 18, 1, 17 and 19 were superior genotypes. In principal component analysis, four components showed 80% of total variations, and the first component with 26% of variation was an important yield component for improving grain yield of barley genotypes. In conclusion, grain yields of winter and spring barley genotypes were

Electrostatic forces on grains near asteroids and comets

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Hartzell Christine

2017-01-01

Full Text Available Dust on and near the surface of small planetary bodies (e.g. asteroids, the Moon, Mars’ moons is subject to gravity, cohesion and electrostatic forces. Due to the very low gravity on small bodies, the behavior of small dust grains is driven by non-gravitational forces. Recent work by Scheeres et al. has shown that cohesion, specifically van der Waals force, is significant for grains on asteroids. In addition to van der Waals cohesion, dust grains also experience electrostatic forces, arising from their interaction with each other (through tribocharging and the solar wind plasma (which produces both grain charging and an external electric field. Electrostatic forces influence both the interactions of grains on the surface of small bodies as well as the dynamics of grains in the plasma sheath above the surface. While tribocharging between identical dielectric grains remains poorly understood, we have recently expanded an existing charge transfer model to consider continuous size distributions of grains and are planning an experiment to test the charge predictions produced. Additionally, we will present predictions of the size of dust grains that are capable of detaching from the surface of small bodies.

Corn yield for silage and grains in different integrated crop-livestock systems

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Laíse da Silveira Pontes

Full Text Available Abstract In this study, the objective was to assess the influence of two doses of N (90 and 180 kg N ha-1, added to the winter pastures, two integrated crop-livestock systems (ICLS, with and without trees and five positions between the tree rows, on the corn (Zea mays L. quality and productivity, for silage and grain. Adopting the complete randomized block design, the treatments included three replicates. In 2006, following the 14 x 3 m spacing (currently with 158 trees ha-1 the trees were planted in 6 out of the 12 paddocks. While the corn was implemented during summer of 2013/2014, cattle grazing on the annual pasture was done during the prior winter, in both ICLS. Corn for silage was reaped at the R5 phenological stage, whereas for grains it was done at 176 days post seeding. For silage, the corn plants were grinded and then stocked in the experimental mini PVC silos. The silage varied slightly in quality along the positions between the tree rows. The differences observed between N levels in the dry matter, crude protein (CP and grain productivity are expressions of the residual effects of the winter fertilization. Silage quality was improved by the shade effect which minimized the acid detergent fiber and raised the CP, although it reduced the corn production for silage and grains by 52%. Some feasible techniques to reduce these losses are discussed.

Molecular dynamics study on microstructure of near grain boundary distortion region in small grain size nano- NiAl alloy

International Nuclear Information System (INIS)

Wang, J.Y.; Wang, X.W.; Rifkin, J.; Li, D.X.

2001-12-01

Using the molecular dynamics simulation method, the microstructure of distortion region near curved amorphous-like grain boundary in nano-NiAl alloy is studied. The results showed that due to the internal elastic force of high energy grain boundary, distortion layer exists between grain and grain boundary. The lattice expansion and structure factor decreasing are observed in this region. Stacking fault in sample with grain size 3.8nm is clearly observed across the distortion region at the site very close to grain. The influences of different grain sizes on average distortion degree and volume fractions of distortion region, grain and grain boundary are also discussed. (author)

Effects Of Spring Herbicide Treatments On Winter Wheat Growth And Grain Yield*

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Hamouz P.

2015-03-01

Full Text Available Herbicides provide a low-cost solution for protecting crops from significant yield losses. If weed infestations are below damage thresholds, however, then herbicide application is unnecessary and can even lead to yield loss. A small-plot field trial was conducted to examine the effect of herbicides on winter wheat yields. Weeds were removed manually from the trial area before herbicide application. Twenty-four treatments were tested in four replications. Treatment 1 consisted of an untreated weed-free control, whereas the other treatments comprised applications of the following herbicides and their combinations: metsulfuron-methyl + tribenuron-methyl (4.95 + 9.99 g ha−1, pinoxaden (30 g ha−1, fluroxypyr (175 g ha−1, and clopyralid (120 g ha−1. Water (250 l ha−1 or a urea-ammonium nitrate fertilizer solution (UAN, 120.5 l ha−1 was used as the herbicide carrier. Crop injury 30 days after treatment and yield loss were recorded. Results showed minor crop injury by herbicides and their combinations when applied without UAN and moderate injury caused by UAN in combination with herbicides. Yield losses reached 5.3% and 4.3% in those treatments where all of the tested herbicides were applied with and without UAN, respectively. The effect of all treatments on crop yield was, however, statistically insignificant (P = 0.934.

Selection of high hectolitre weight mutants of winter wheat

International Nuclear Information System (INIS)

Crowley, C.; Jones, P.

1989-01-01

Grain quality in wheat includes hectolitre weight (HLW) besides protein content and thousand-grain weight (TGW). The British winter wheat variety ''Guardian'' has a very high yield potential. Although the long grain of ''Guardian'' results in a desirable high TGW the HLW is too low. To select mutants exhibiting increased HLW the character was first analyzed to identify traits that could more easily be screened for using M 2 seeds. In comparison of 6 wheat cultivars, correlation analyses with HLW resulted in coefficients of -0.86 (grain length, L:P 2 seeds for shorter, less prolate grains. Mutagenesis was carried out using EMS sulphonate (1.8 or 3.6%), sodium azide (2 or 20 mM) or X-rays (7.5 or 20 kR). 69 M 2 grains with altered shape were selected. Examination of the M 3 progeny confirmed 6 grain-shape mutants, most of them resulting from EMS treatment (Table). Two of the mutants showed TGW values significantly below the parental variety, but three mutants exhibited HLW and TGW values significantly greater than those of the parental variety. Microplot yield trails on selected M 3 lines are in progress. The influence of physical grain characteristics on HLW offers prospects for mechanical fractionation of large M 2 populations. The application of gravity separators (fractionation on the basis of grain density) and sieves (fractionation on the basis of grain length) in screening mutants possessing improved grain quality is being investigated

Wheat grain mechanical vulnerability to mechanical damage in light of the recent agrophysical research

International Nuclear Information System (INIS)

Grundas, S.

1995-01-01

The paper contains basic information on mechanical damage to wheat grains. The most important causes of mechanical damage and some of its effects in manufacturing are discussed. Grain material included 5 varieties of winter wheat and 2 varieties of spring wheat. Internal mechanical damage was examined by X-ray technique; external damage was examined with the colorimeter method. The results obtained were compared with the estimation results of more important processing features of the grain: gluten quantity and quality and grain hardness. (author)

Mapping of QTLs for leaf area and the association with winter ...

African Journals Online (AJOL)

Variations in plant architecture are often associated with the ability of plants to survive cold stress during winter. In studies of winter hardiness in lentil, it appeared that small leaf area was associated with improved winter survival. Based on this observation, the inheritance of leaf area and the relationship with winter ...

Genome-wide Association Analysis of Kernel Weight in Hard Winter Wheat

Science.gov (United States)

Wheat kernel weight is an important and heritable component of wheat grain yield and a key predictor of flour extraction. Genome-wide association analysis was conducted to identify genomic regions associated with kernel weight and kernel weight environmental response in 8 trials of 299 hard winter ...

Variability in carbon dioxide fluxes among six winter wheat paddocks managed under different tillage and grazing practices

Science.gov (United States)

Carbon dioxide (CO2) fluxes from six winter wheat (Triticum aestivum L.) paddocks (grain only, graze-grain, and graze-out) managed under conventional till (CT) and no-till (NT) systems were synthesized for the 2016-2017 growing season to compare the magnitudes and seasonal dynamics of CO2 fluxes and...

Winter-to-winter variations in indoor radon

International Nuclear Information System (INIS)

Mose, D.G.; Mushrush, G.W.; Kline, S.W.

1989-01-01

Indoor radon concentrations in northern Virginia and central Maryland show a strong dependence on weather. Winter tends to be associated with higher than average indoor radon, and summer with lower than average. However, compared to the winter of 1986-1987, the winter of 1987-1988 was warmer and drier. Consequently, winter-to-winter indoor radon decreased by about 25%. This winter-to-winter decrease is unexpectedly large, and simulates winter-to-summer variations that have been reported

[Effects of water deficit and nitrogen fertilization on winter wheat growth and nitrogen uptake].

Science.gov (United States)

Qi, You-Ling; Zhang, Fu-Cang; Li, Kai-Feng

2009-10-01

Winter wheat plants were cultured in vitro tubes to study their growth and nitrogen uptake under effects of water deficit at different growth stages and nitrogen fertilization. Water deficit at any growth stages could obviously affect the plant height, leaf area, dry matter accumulation, and nitrogen uptake. Jointing stage was the most sensitive stage of winter wheat growth to water deficit, followed by flowering stage, grain-filling stage, and seedling stages. Rewatering after the water deficit at seedling stage had a significant compensation effect on winter wheat growth, and definite compensation effect was observed on the biomass accumulation and nitrogen absorption when rewatering was made after the water deficit at flowering stage. Under the same nitrogen fertilization levels, the nitrogen accumulation in root with water deficit at seedling, jointing, flowering, and grain-filling stages was reduced by 25.82%, 55.68%, 46.14%, and 16.34%, and the nitrogen accumulation in aboveground part was reduced by 33.37%, 51.71%, 27.01%, and 2.60%, respectively, compared with no water deficit. Under the same water deficit stages, the nitrogen content and accumulation of winter wheat decreased with decreasing nitrogen fertilization level, i. e., 0.3 g N x kg(-1) FM > 0.2 g N x kg(-1) FM > 0.1 g N x kg(-1) FM. Nitrogen fertilization had obvious regulation effect on winter wheat plant growth, dry matter accumulation, and nitrogen uptake under water stress.

The Structure of Pre-Transitional Protoplanetary Disks. II Azimuthal Asymmetries, Different Radial Distributions of Large and Small Dust Grains in PDS 70

Science.gov (United States)

Hashimoto, J.; Tsukagoshi, T.; Brown, J. M.; Dong, R.; Muto, T.; Zhu, Z.; Wisniewski, J.; Ohashi, N.; Kudo, T.; Kusakabe, N.;

Radial decoupling of small and large dust grains in the transitional disk RX J1615.3-3255

Science.gov (United States)

Kooistra, Robin; Kamp, Inga; Fukagawa, Misato; Menard, Francois; Momose, Munetake; Tsukagoshi, Takashi; Kudo, Tomoyuki; Kusakabe, Nobuhiko; Hashimoto, Jun; Abe, Lyu;

Research on spatial distribution of photosynthetic characteristics of Winter Wheat

Science.gov (United States)

Yan, Q. Q.; Zhou, Q. Y.; Zhang, B. Z.; Han, X.; Han, N. N.; Li, S. M.

2018-03-01

In order to explore the spatial distribution of photosynthetic characteristics of winter wheat leaf, the photosynthetic rate on different parts of leaf (leaf base-leaf middle-leaf apex) and that on each canopy (top layer-middle layer-bottom layer) leaf during the whole growth period of winter wheat were measured. The variation of photosynthetic rate with PAR and the spatial distribution of winter wheat leaf during the whole growth periods were analysed. The results showed that the photosynthetic rate of different parts of winter wheat increased with the increase of PAR, which was showed as leaf base>leaf middle>leaf apex. In the same growth period, photosynthetic rate in different parts of the tablet was showed as leaf middle>leaf base>leaf apex. For the different canopy layer of winter wheat, the photosynthetic rate of the top layer leaf was significantly greater than that of the middle layer and lower layer leaf. The photosynthetic rate of the top layer leaf was the largest in the leaf base position. The photosynthetic rate of leaf of the same canopy layer at different growth stages were showed as tasseling stage >grain filling stage > maturation stage.

Interstellar grains

Energy Technology Data Exchange (ETDEWEB)

Hoyle, F.; Wickramasinghe, N.C.

1980-11-01

Interstellar extinction of starlight was observed and plotted as a function of inverse wavelength. Agreement with the calculated effects of the particle distribution is shown. The main kinds of grain distinguished are: (1) graphite spheres of radius 0.02 microns, making up 10% of the total grain mass (2) small dielectric spheres of radius 0.04 microns making up 25% and (3) hollow dielectric cylinders containing metallic iron, with diameters of 2/3 microns making up 45%. The remaining 20% consists of other metals, metal oxides, and polysiloxanes. Absorption factor evidence suggests that the main dielectric component of the grains is organic material.

Effects of Favorable Alleles for Water-Soluble Carbohydrates at Grain Filling on Grain Weight under Drought and Heat Stresses in Wheat

Science.gov (United States)

Chang, Xiaoping; Li, Runzhi; Jing, Ruilian

2014-01-01

Drought, heat and other abiotic stresses during grain filling can result in reductions in grain weight. Conserved water-soluble carbohydrates (WSC) at early grain filling play an important role in partial compensation of reduced carbon supply. A diverse population of 262 historical winter wheat accessions was used in the present study. There were significant correlations between 1000-grain weight (TGW) and four types of WSC, viz. (1) total WSC at the mid-grain filling stage (14 days after flowering) produced by leaves and non-leaf organs; (2) WSC contributed by current leaf assimilation during the mid-grain filling; (3) WSC in non-leaf organs at the mid-grain filling, excluding the current leaf assimilation; and (4) WSC used for respiration and remobilization during the mid-grain filling. Association and favorable allele analyses of 209 genome-wide SSR markers and the four types of WSC were conducted using a mixed linear model. Seven novel favorable WSC alleles exhibited positive individual contributions to TGW, which were verified under 16 environments. Dosage effects of pyramided favorable WSC alleles and significantly linear correlations between the number of favorable WSC alleles and TGW were observed. Our results suggested that pyramiding more favorable WSC alleles was effective for improving both WSC and grain weight in future wheat breeding programs. PMID:25036550

CO2 Dynamics in winter wheat and canola under different management practices in the Southern Great Plains

Science.gov (United States)

Wagle, P.; Manjunatha, P.; Gowda, P. H.; Northup, B. K.; Neel, J. P. S.; Turner, K.; Steiner, J. L.

2017-12-01

Rising atmospheric carbon dioxide (CO2) concentration and increased air temperature and climatic variability concerns have prompted considerable interest regarding CO2 dynamics of terrestrial ecosystems in response to major climatic and biophysical factors. However, detailed information on CO2 dynamics in winter wheat (Triticum aestivum L.) and canola (Brassica napus L.) under different agricultural management practices is lacking. As a part of the GRL-FLUXNET, a cluster of eight eddy covariance (EC) systems was deployed on the 420-ha Grazinglands Research on agroEcosystems and the ENvironment (GREEN) Farm at the United States Department of Agriculture, Agricultural Research Service (USDA-ARS), Grazinglands Research Laboratory (GRL), El Reno, OK. The GRL is also one of 18 USDA-ARS Long-Term Agroecosystem Research (LTAR) network sites in the United States. A 4-year crop rotation plan at the farm includes winter wheat for grain only, graze-grain, and graze-out, and canola under conventional till and no-till management conditions. Biometric measurements such as biomass, leaf area index (LAI), canopy cover %, canopy height, and chlorophyll content were collected approximately every 16 days to coincide with Landsat satellite overpass dates. As expected, biomass and LAI were highest in the grain only wheat fields followed by graze-grain and graze-out wheat fields, but they were similar for till and no-till wheat fields within the same grazing practice. Biomass and LAI were similar in till and no-till canola in fall 2016, but both were substantially lower in no-till compared to tilled canola during spring 2017 due to more severe winter damage. Because net ecosystem CO2 exchange (NEE) is strongly regulated by vegetation cover, the magnitudes of NEE were highest in the grain only wheat fields due to more biomass and LAI, followed by graze-grain and graze-out wheat fields. Similarly, the magnitudes of NEE were also higher in tilled canola (i.e., higher biomass and LAI) than

Effects of elevated O3 concentration on winter wheat and rice yields in the Yangtze River Delta, China

International Nuclear Information System (INIS)

Wang Xiaoke; Zhang Qianqian; Zheng Feixiang; Zheng Qiwei; Yao Fangfang; Chen Zhan; Zhang Weiwei; Hou Peiqiang; Feng Zhaozhong; Song Wenzhi; Feng Zongwei; Lu Fei

2012-01-01

The effects of a continuing rise of ambient ozone on crop yield will seriously threaten food security in China. In the Yangtze River Delta, a rapidly developing and seriously air polluted region in China, innovative open-top chambers have been established to fumigate winter wheat and rice in situ with elevated O 3 . Five years of study have shown that the yields of wheat and rice decreased with increasing O 3 concentration. There were significant relationships between the relative yield and AOT40 (accumulated hourly O 3 concentration over 40 ppb) for both winter wheat and rice. Winter wheat was more sensitive to O 3 than rice. O 3 -induced yield declines were attributed primarily to 1000-grain weight and harvest index for winter wheat, and attributed primarily to grain number per panicle and harvest index for rice. Control of ambient O 3 pollution and breeding of O 3 tolerant crops are urgent to guarantee food security in China. - Highlights: ► The wheat and rice response to ozone had been investigated for five years in China. ► There were significant relationships between relative crop yields and AOT40 dose. ► O 3 -induced wheat yield loss was primarily due to 1000-grain weight and harvest index. ► O 3 -induced rice yield loss was primarily due to grains per panicle and harvest index. ► Wheat and rice in this study are more sensitive to O 3 than previous investigations. - The dose–response relationships derived from field fumigation experiments over 5 years can be used to accurately estimate crop losses in China.

Nitrogen dynamics following grain legumes and subsequent catch crops and the effects on succeeding cereal crops

DEFF Research Database (Denmark)

Hauggaard-Nielsen, Henrik; Mundus, Simon; Jensen, Erik Steen

2009-01-01

balances. A 2½-year lysimeter experiment was carried out on a temperate sandy loam soil. Crops were not fertilized in the experimental period and the natural 15N abundance technique was used to determine grain legume N2 fixation. Faba bean total aboveground DM production was significantly higher (1,300 g m...... on the subsequent spring wheat or winter triticale DM production. Nitrate leaching following grain legumes was significantly reduced with catch crops compared to without catch crops during autumn and winter before sowing subsequent spring wheat. Soil N balances were calculated from monitored N leaching from...

Short-term winter wheat (Triticum aestivum L.) cover crop grazing influence on calf growth, grain yield, and soil properties

Science.gov (United States)

Winter cover cropping has many agronomic benefits and can provide forages base for spring livestock grazing. Winter cover crop grazing has shown immediate economic benefits through increased animal production. Winter wheat pasture grazing is common in beef cow-calf production and stocker operations....

Whole Grains Contribute Only a Small Proportion of Dietary Fiber to the U.S. Diet

Directory of Open Access Journals (Sweden)

Sibylle Kranz

2017-02-01

Full Text Available Dietary fiber (DF, found in whole fruits, vegetables, and whole grains (WG, is considered a nutrient of concern in the US diet and increased consumption is recommended. The present study was designed to highlight this critical importance of the difference between WG, high-fiber WG, and sources of fiber that are not from WG. The study is based on the two-day diets reported consumed by the nationally representative sample of Americans participating in What We Eat In America, the dietary component of the National Health and Nutrition Examination Survey from 2003–2010. Foods consumed were classified into tertiles of DF and WG and the contribution of fiber by differing levels of WG content were examined. Foods containing high amounts of WG and DF only contributed about 7% of total fiber intake. Overall, grain-based foods contributed 54.5% of all DF consumed. Approximately 39% of DF came from grain foods that contained no WG, rather these foods contained refined grains, which contain only small amounts of DF but are consumed in large quantities. All WG-containing foods combined contributed a total of 15.3% of DF in the American diet. Thus, public health messaging needs to be changed to specifically encourage consumption of WG foods with high levels of DF to address both recommendations.

Development of Perennial Grain Sorghum

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Stan Cox

2018-01-01

Full Text Available Perennial germplasm derived from crosses between Sorghum bicolor and either S. halepense or S. propinquum is being developed with the goal of preventing and reversing soil degradation in the world’s grain sorghum-growing regions. Perennial grain sorghum plants produce subterranean stems known as rhizomes that sprout to form the next season’s crop. In Kansas, breeding perennial sorghum involves crossing S. bicolor cultivars or breeding lines to S. halepense or perennial S. bicolorn × S. halepense breeding lines, selecting perennial plants from F2 or subsequent populations, crossing those plants with S. bicolor, and repeating the cycle. A retrospective field trial in Kansas showed that selection and backcrossing during 2002–2009 had improved grain yields and seed weights of breeding lines. Second-season grain yields of sorghum lines regrowing from rhizomes were similar to yields in the first season. Further selection cycles have been completed since 2009. Many rhizomatous lines that cannot survive winters in Kansas are perennial at subtropical or tropical locations in North America and Africa. Grain yield in Kansas was not correlated with rhizomatousness in either Kansas or Uganda. Genomic regions affecting rhizome growth and development have been mapped, providing new breeding tools. The S. halepense gene pool may harbor many alleles useful for improving sorghum for a broad range of traits in addition to perenniality.

MULTIGRAIN: a smoothed particle hydrodynamic algorithm for multiple small dust grains and gas

Science.gov (United States)

Hutchison, Mark; Price, Daniel J.; Laibe, Guillaume

2018-05-01

We present a new algorithm, MULTIGRAIN, for modelling the dynamics of an entire population of small dust grains immersed in gas, typical of conditions that are found in molecular clouds and protoplanetary discs. The MULTIGRAIN method is more accurate than single-phase simulations because the gas experiences a backreaction from each dust phase and communicates this change to the other phases, thereby indirectly coupling the dust phases together. The MULTIGRAIN method is fast, explicit and low storage, requiring only an array of dust fractions and their derivatives defined for each resolution element.

Winter Crop Mapping for Improving Crop Production Estimates in Argentina Using Moderation Resolution Satellite Imagery

Science.gov (United States)

Humber, M. L.; Copati, E.; Sanchez, A.; Sahajpal, R.; Puricelli, E.; Becker-Reshef, I.

2017-12-01

Accurate crop production data is fundamental for reducing uncertainly and volatility in the domestic and international agricultural markets. The Agricultural Estimates Department of the Buenos Aires Grain Exchange has worked since 2000 on the estimation of different crop production data. With this information, the Grain Exchange helps different actors of the agricultural chain, such as producers, traders, seed companies, market analyst, policy makers, into their day to day decision making. Since 2015/16 season, the Grain Exchange has worked on the development of a new earth observations-based method to identify winter crop planted area at a regional scale with the aim of improving crop production estimates. The objective of this new methodology is to create a reliable winter crop mask at moderate spatial resolution using Landsat-8 imagery by exploiting bi-temporal differences in the phenological stages of winter crops as compared to other landcover types. In collaboration with the University of Maryland, the map has been validated by photointerpretation of a stratified statistically random sample of independent ground truth data in the four largest producing provinces of Argentina: Buenos Aires, Cordoba, La Pampa, and Santa Fe. In situ measurements were also used to further investigate conditions in the Buenos Aires province. Preliminary results indicate that while there are some avenues for improvement, overall the classification accuracy of the cropland and non-cropland classes are sufficient to improve downstream production estimates. Continuing research will focus on improving the methodology for winter crop mapping exercises on a yearly basis as well as improving the sampling methodology to optimize collection of validation data in the future.

THE STRUCTURE OF PRE-TRANSITIONAL PROTOPLANETARY DISKS. II. AZIMUTHAL ASYMMETRIES, DIFFERENT RADIAL DISTRIBUTIONS OF LARGE AND SMALL DUST GRAINS IN PDS 70 {sup ,}

Energy Technology Data Exchange (ETDEWEB)

Hashimoto, J.; Wisniewski, J. [Department of Physics and Astronomy, The University of Oklahoma, 440 West Brooks Street, Norman, OK 73019 (United States); Tsukagoshi, T. [College of Science, Ibaraki University, Bunkyo 2-1-1, Mito 310-8512 (Japan); Brown, J. M. [Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, MS 78, Cambridge, MA 02138 (United States); Dong, R. [Astronomy Department, University of California, Berkeley, CA 94720 (United States); Muto, T. [Division of Liberal Arts, Kogakuin University, 1-24-2, Nishi-Shinjuku, Shinjuku-ku, Tokyo 163-8677 (Japan); Zhu, Z. [Department of Astrophysical Sciences, Princeton University, Princeton, NJ 08544 (United States); Ohashi, N.; Kudo, T.; Egner, S.; Guyon, O. [Subaru Telescope, 650 North A' ohoku Place, Hilo, HI 96720 (United States); Kusakabe, N.; Akiyama, E. [National Astronomical Observatory of Japan, 2-21-1 Osawa, Mitaka, Tokyo 181-8588 (Japan); Abe, L. [Laboratoire Hippolyte Fizeau, UMR6525, Universite de Nice Sophia-Antipolis, 28, avenue Valrose, F-06108 Nice Cedex 02 (France); Brandner, W.; Carson, J.; Feldt, M. [Max Planck Institute for Astronomy, Königstuhl 17, D-69117 Heidelberg (Germany); Brandt, T. [Astrophysics Department, Institute for Advanced Study, Princeton, NJ (United States); Currie, T. [Department of Astronomy and Astrophysics, University of Toronto, 50 St. George Street, Toronto, ON (Canada); Grady, C. A., E-mail: jun.hashimoto@ou.edu [Eureka Scientific, 2452 Delmer, Suite 100, Oakland, CA 96002 (United States); and others

2015-01-20

The formation scenario of a gapped disk, i.e., transitional disk, and its asymmetry is still under debate. Proposed scenarios such as disk-planet interaction, photoevaporation, grain growth, anticyclonic vortex, eccentricity, and their combinations would result in different radial distributions of the gas and the small (sub-μm size) and large (millimeter size) dust grains as well as asymmetric structures in a disk. Optical/near-infrared (NIR) imaging observations and (sub-)millimeter interferometry can trace small and large dust grains, respectively; therefore multi-wavelength observations could help elucidate the origin of complicated structures of a disk. Here we report Submillimeter Array observations of the dust continuum at 1.3 mm and {sup 12}CO J = 2 → 1 line emission of the pre-transitional protoplanetary disk around the solar-mass star PDS 70. PDS 70, a weak-lined T Tauri star, exhibits a gap in the scattered light from its disk with a radius of ∼65 AU at NIR wavelengths. However, we found a larger gap in the disk with a radius of ∼80 AU at 1.3 mm. Emission from all three disk components (the gas and the small and large dust grains) in images exhibits a deficit in brightness in the central region of the disk, in particular, the dust disk in small and large dust grains has asymmetric brightness. The contrast ratio of the flux density in the dust continuum between the peak position to the opposite side of the disk reaches 1.4. We suggest the asymmetries and different gap radii of the disk around PDS 70 are potentially formed by several (unseen) accreting planets inducing dust filtration.

Responses of Winter Wheat Yields to Warming-Mediated Vernalization Variations Across Temperate Europe

Directory of Open Access Journals (Sweden)

Xiuchen Wu

2017-10-01

Full Text Available Rapid climate warming, with much higher warming rates in winter and spring, could affect the vernalization fulfillment, a critical process for induction of crop reproductive growth and consequent grain filling in temperate winter crops. However, regional observational evidence of the effects of historical warming-mediated vernalization variations on temperate winter crop yields is lacking. Here, we statistically quantified the interannual sensitivity of winter wheat yields to vernalization degree days (VDD during 1975–2009 and its spatial relationship with multi-year mean VDD over temperate Europe (TE, using EUROSTAT crop yield statistics, observed and simulated crop phenology data and gridded daily climate data. Our results revealed a pervasively positive interannual sensitivity of winter wheat yields to variations in VDD (γVDD over TE, with a mean γVDD of 2.8 ± 1.5 kg ha−1 VDD−1. We revealed a significant (p < 0.05 negative exponential relationship between γVDD and multi-year mean VDD for winter wheat across TE, with higher γVDD in winter wheat planting areas with lower multi-year mean VDD. Our findings shed light on potential vulnerability of winter wheat yields to warming-mediated vernalization variations over TE, particularly considering a likely future warmer climate.

Changes in the elemental composition of winter wheat plants caused by the action of Megafol and retardants

Directory of Open Access Journals (Sweden)

I. M. Miroshnichenko

2017-08-01

Full Text Available In the course of field experiments conducted during the 2015–2016 vegetation seasons, retardants Medax Top, 1.0 l/ha (prohexadione-Са and mepiquat-chloride, appeared more effective than Terpal, 1.5 l/ha (mepiquat-chloride and ethephon, on field plots with high-yield varieties. Foliar application of Megafol promoted the productivity of winter wheat varieties Smuglyanka and Podolyanka and reduced the negative influence of retardants on the wheat plants in the vegetation seasons which were characterized by moisture deficit. The influence of modern retardants – prohexadione-Ca + mepiquat-chloride (Medax Top and mepiquat-chloride + etefone (Terpal, both BASF, Germany on the accumulation of some macro- and micronutrients in winter wheat plants was determined. The assays were performed on an ICP-MS Agilent 7700x mass spectrometer (Agilent Technologies, USA with ICP-MS Mass Hunter WorkStation. Samples of winter wheat plants were taken in the phase of flowering and grain ripening. The samples were dried, homogenized, 0.400 gof weight was dissolved in ICP-grade nitric acid in the Milestone Start D (Milestone Inc., USA. All solutions were prepared on 1st class water (18 MΩ cm–1 obtained on the Scholar-UV Nex Up 1000 (Human Corporation, Korea water purification system. The ICP-MS Complete Standard IV-ICPMS-71A was used as the external standard, and the internal standard was Sc, both of Inorganic Ventures, USA. According to the ICP-MS results of plant samples of winter wheat of Smuglylanka and Podolanka, it has been shown that, in conditions of wheat growing on light soils of Polissya, modern compositional retardants affect the ionome of plants during the vegetation season, as well as change the content of inorganic elements in the grain. It was found that winter wheat of the middle-stem intensive Podolyanka type reacted more responsively to retardant treatment than the short-stem highly intensive Smuglyanka type. At the same time, there was an

Flowering time control in European winter wheat

Directory of Open Access Journals (Sweden)

Simon Martin Langer

2014-10-01

Full Text Available Flowering time is an important trait in wheat breeding as it affects adaptation and yield potential. The aim of this study was to investigate the genetic architecture of flowering time in European winter bread wheat cultivars. To this end a population of 410 winter wheat varieties was evaluated in multi-location field trials and genotyped by a genotyping-by-sequencing approach and candidate gene markers. Our analyses revealed that the photoperiod regulator Ppd-D1 is the major factor affecting flowering time in this germplasm set, explaining 58% of the genotypic variance. Copy number variation at the Ppd-B1 locus was present but explains only 3.2% and thus a comparably small proportion of genotypic variance. By contrast, the plant height loci Rht-B1 and Rht-D1 had no effect on flowering time. The genome-wide scan identified six QTL which each explain only a small proportion of genotypic variance and in addition we identified a number of epistatic QTL, also with small effects. Taken together, our results show that flowering time in European winter bread wheat cultivars is mainly controlled by Ppd-D1 while the fine tuning to local climatic conditions is achieved through Ppd-B1 copy number variation and a larger number of QTL with small effects.

Abnormal grain growth: a non-equilibrium thermodynamic model for multi-grain binary systems

International Nuclear Information System (INIS)

Svoboda, J; Fischer, F D

2014-01-01

Abnormal grain growth as the abrupt growth of a group of the largest grains in a multi-grain system is treated within the context of unequal retardation of grain growth due to the segregation of solute atoms from the bulk of the grains into the grain boundaries. During grain boundary migration, the segregated solute atoms are dragged under a small driving force or left behind the migrating grain boundary under a large driving force. Thus, the solute atoms in the grain boundaries of large grains, exhibiting a large driving force, can be released from the grain boundary. The mobility of these grain boundaries becomes significantly higher and abnormal grain growth is spontaneously provoked. The mean-field model presented here assumes that each grain is described by its grain radius and by its individual segregation parameter. The thermodynamic extremal principle is engaged to obtain explicit evolution equations for the radius and segregation parameter of each grain. Simulations of grain growth kinetics for various conditions of segregation with the same initial setting (100 000 grains with a given radius distribution) are presented. Depending on the diffusion coefficients of the solute in the grain boundaries, abnormal grain growth may be strongly or marginally pronounced. Solute segregation and drag can also significantly contribute to the stabilization of the grain structure. Qualitative agreement with several experimental results is reported. (paper)

Physics of dust grains in hot gas

International Nuclear Information System (INIS)

Draine, B.T.; Salpeter, E.E.

1979-01-01

Charging of dust grains in hot (10 4 --10 9 K) plasma is studied, including photoelectron and secondary electron emission, field emission, and transmission of electrons and ions through the grain; resulting grain potentials are (for T > or approx. = 10 5 K) considerably smaller in magnitude than found by Burke and Silk. Even so, large electrostatic stresses can cause ion field emission and rapid destruction of small grains in very hot gas. Rapid rotation can also disrupt small grains, but damping (by microwave emission) usually limits the centrifugal stress to acceptable values for plasma densities n/sub H/ -3 . Sputtering rates are estimated for grains in hot gas, based upon a semiempirical fit to experimental data. Predicted sputtering rates for possible grain constituents are similar to estimates by Barlow, but in some cases differ significantly. Useful approximation formulae are given for the drag forces acting on a grain with arbitrary Mach number

Effects of Post-Anthesis Drought and Waterlogging on Accumulation of High-Molecular-Weight Glutenin Subunits and Glutenin Macropolymers Content in Wheat Grain

DEFF Research Database (Denmark)

Jiang, D; Yue, H; Wollenweber, B

2009-01-01

Drought and flooding during grain filling have become major constraints to wheat quality and yield. The impacts of water deficits and waterlogging during the grain filling on contents of high-molecular-weight glutenin subunits (HMW-GS) and of glutenin macropolymers (GMP) in grains of the winter w...

Why do interstellar grains exist

International Nuclear Information System (INIS)

Seab, C.G.; Hollenbach, D.J.; Mckee, C.F.; Tielens, A.G.G.M.

1986-01-01

There exists a discrepancy between calculated destruction rates of grains in the interstellar medium and postulated sources of new grains. This problem was examined by modelling the global life cycle of grains in the galaxy. The model includes: grain destruction due to supernovae shock waves; grain injection from cool stars, planetary nebulae, star formation, novae, and supernovae; grain growth by accretion in dark clouds; and a mixing scheme between phases of the interstellar medium. Grain growth in molecular clouds is considered as a mechanism or increasing the formation rate. To decrease the shock destruction rate, several new physical processes, such as partial vaporization effects in grain-grain collisions, breakdown of the small Larmor radius approximation for betatron acceleration, and relaxation of the steady-state shock assumption are included

Response of water use efficiency and carbon emission to no-tillage and winter wheat genotypes in the North China Plain.

Science.gov (United States)

Ren, Yujie; Gao, Chao; Han, Huifang; Li, Quanqi

2018-04-20

No-tillage management practices reduce net CO 2 losses from farmland and keep soil from degrading, but also decrease winter wheat grain yield and water use efficiency (WUE) in the North China Plain (NCP). Suitable management practices, namely, the choice of genotypes, could enhance crop yield and WUE; however, how the WUE and CO 2 exchange responds to no-tillage practices and winter wheat genotypes remains unclear. In the 2015-2016 and 2016-2017 winter wheat growing seasons in the NCP, a field experiment was carried out, and tested two tillage methods (no-tillage with mulching and conventional tillage) and two winter wheat genotypes ('Tainong 18' and 'Jimai 22'). The goal of the study was to identify the relationship between winter wheat grain yield, water consumption, and carbon emissions in no-tillage practices. The results showed that, compared to conventional tillage, no-tillage significantly reduced the net CO 2 -C cumulative emissions and water consumption; however, the grain yield was significantly reduced by 6.8% and 12.0% in the first and second growing seasons, respectively. Compared with Jimai 22, Tainong 18 had a compensatory effect on the yield reduction caused by no-tillage. As a result, the yield carbon utilization efficiency (R) and WUE were the highest in no-tillage with Tainong 18 (NT18), and the carbon emission per unit water consumption was the lowest in NT18. The results support the idea that a combination of no-tillage with genotype can improve the regulation of soil carbon emissions and water consumption of winter wheat, thus, providing theoretical support for sustainable crop production and soil development in the NCP. Copyright © 2018 Elsevier B.V. All rights reserved.

Titan's Emergence from Winter

Science.gov (United States)

Flasar, F. Michael; Achterberg, Richard; Jennings, Donald; Schinder, Paul

2011-01-01

We summarize the changes in Titans thermal structure derived from Cassini CIRS and radio-occultation data during the transition from winter to early spring. Titan's surface, and middle atmosphere show noticeable seasonal change, whereas that in most of the troposphere is mated. This can be understood in terms of the relatively small radiative relaxation time in the middle atmosphere and much larger time scale in the troposphere. The surface exhibits seasonal change because the heat capacity in an annual skin depth is much smaller than that in the lowest scale height of the troposphere. Surface temperatures rise 1 K at raid and high latitudes in the winter northern hemisphere and cool in the southern hemisphere. Changes in in the middle atmosphere are more complicated. Temperatures in the middle stratosphere (approximately 1 mbar) increase by a few kelvin at mid northern latitudes, but those at high latitudes first increase as that region moves out of winter shadow, and then decrease. This probably results from the combined effect of increased solar heating as the suit moves higher in the sky and the decreased adiabatic warming as the sinking motions associated with the cross-equatorial meridional cell weaken. Consistent with this interpretation, the warm temperatures observed higher up at the winter polar stratopause cool significantly.

On the relation between ionospheric winter anomalies and solar wind

International Nuclear Information System (INIS)

Rumi, G.C.

2001-01-01

There are two different winter anomalies. A small one that appears in connection with ionization at relatively low latitudes in the bottom of the D-region of the ionosphere. There, the electron densities in the winter happen to be less than should be expected. On the other hand, the classic winter anomaly is present when in the winter the upper D-region, again at relatively low latitudes, has more ionization than should be expected. Both these effects are due to the slant compression of the geomagnetic field produced by the solar wind in the wind in the winter season (which is, of course, the summer season when reference is made to events in the other hemisphere). It is shown that the small winter anomaly is a consequence of a hemispheric imbalance in the flux of galactic cosmic rays determined by the obliquely distorted geomagnetic field. It is shown that the standard winter anomaly can be ascribed to the influx of a super solar wind, which penetrates into the Earth's polar atmosphere down to E-region, heights and, duly concentrated through a funneling action at the winter pole of the distorted geomagnetic field, slows down the winter polar vortex. An equatorward motion of the polar air with its content of nitric oxide brings about the excess of ionization in the upper D-region at lower latitudes. The experimentally observed rhythmic recurrence of the upper winter anomaly is correlated to a possible rhythmic recurrence of the super solar wind. The actual detection of the upper winter anomaly could yield some information on the velocity of the basic solar wind. A by-product of the present analysis, the determination of Γ, the coefficient of collisional detachment of the electrons from the O 2 - ions, is presented in the Appendix

On the relation between ionospheric winter anomalies and solar wind

Energy Technology Data Exchange (ETDEWEB)

Rumi, G.C. [Lecco, (Italy)

2001-06-01

There are two different winter anomalies. A small one that appears in connection with ionization at relatively low latitudes in the bottom of the D-region of the ionosphere. There, the electron densities in the winter happen to be less than should be expected. On the other hand, the classic winter anomaly is present when in the winter the upper D-region, again at relatively low latitudes, has more ionization than should be expected. Both these effects are due to the slant compression of the geomagnetic field produced by the solar wind in the wind in the winter season (which is, of course, the summer season when reference is made to events in the other hemisphere). It is shown that the small winter anomaly is a consequence of a hemispheric imbalance in the flux of galactic cosmic rays determined by the obliquely distorted geomagnetic field. It is shown that the standard winter anomaly can be ascribed to the influx of a super solar wind, which penetrates into the Earth's polar atmosphere down to E-region, heights and, duly concentrated through a funneling action at the winter pole of the distorted geomagnetic field, slows down the winter polar vortex. An equatorward motion of the polar air with its content of nitric oxide brings about the excess of ionization in the upper D-region at lower latitudes. The experimentally observed rhythmic recurrence of the upper winter anomaly is correlated to a possible rhythmic recurrence of the super solar wind. The actual detection of the upper winter anomaly could yield some information on the velocity of the basic solar wind. A by-product of the present analysis, the determination of {gamma}, the coefficient of collisional detachment of the electrons from the O{sub 2} {sup -} ions, is presented in the Appendix.

Effects of Zn, macronutrients, and their interactions through foliar applications on winter wheat grain nutritional quality.

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Shaoxia Wang

Full Text Available Although application of Zn combined with macronutrients (K, P, and N can be used to fortify wheat grain with Zn, little is known about their interactions when foliar application is employed or the influences of common soil fertility management practices (e.g. N and straw management on their efficiency. Therefore, the effects of foliar-applied Zn and N, P, or K on grain nutritional quality (especially Zn were investigated in wheat grown under different soil N rates at two sites with (Sanyuan or without (Yangling employing straw return. A 4-year-long field experiment was also conducted to evaluate the environmental stability of the foliar formulations. Across 6 site-years, foliar Zn application alone or combined with N, P, or K fertilizers resulted in 95.7%, 101%, 67.9% and 121% increases in grain Zn concentration, respectively. In terms of increasing grain Zn concentration, foliar-applied Zn positively interacted with N (at Sanyuan and K (at Yangling, but negatively interacted with P at any condition tested, suggesting depressive effects of foliarly-applied P on physiological availability of Zn. Although these interaction effects were the major factor that governing the efficiency of foliar-applied Zn combined with N, P, or K on grain Zn concentration, the magnitude of the increase/decrease in grain Zn (-3.96~5.71 mg kg-1 due to these interactions was much less than the average increases following Zn+K (31.3, Zn+P (18.7, and Zn+N (26.5 mg kg-1 treatments relative to that observed in foliar Zn-only treatment. The combined foliar application of Zn with N, P, or K did not cause any adverse impact on grain yield and other nutritional quality and in some cases slightly increased grain yield and macronutrient concentrations. Grain phytic acid:Zn molar ratios were respectively 52.0%, 53.1%, 43.4% and 63.5% lower in the foliar Zn, Zn+N, Zn+P and Zn+K treatments than in the control treatment. These effects were consistent over four years and across three

Effects of Zn, macronutrients, and their interactions through foliar applications on winter wheat grain nutritional quality.

Science.gov (United States)

Wang, Shaoxia; Li, Meng; Liu, Ke; Tian, Xiaohong; Li, Shuo; Chen, Yanlong; Jia, Zhou

2017-01-01

Although application of Zn combined with macronutrients (K, P, and N) can be used to fortify wheat grain with Zn, little is known about their interactions when foliar application is employed or the influences of common soil fertility management practices (e.g. N and straw management) on their efficiency. Therefore, the effects of foliar-applied Zn and N, P, or K on grain nutritional quality (especially Zn) were investigated in wheat grown under different soil N rates at two sites with (Sanyuan) or without (Yangling) employing straw return. A 4-year-long field experiment was also conducted to evaluate the environmental stability of the foliar formulations. Across 6 site-years, foliar Zn application alone or combined with N, P, or K fertilizers resulted in 95.7%, 101%, 67.9% and 121% increases in grain Zn concentration, respectively. In terms of increasing grain Zn concentration, foliar-applied Zn positively interacted with N (at Sanyuan) and K (at Yangling), but negatively interacted with P at any condition tested, suggesting depressive effects of foliarly-applied P on physiological availability of Zn. Although these interaction effects were the major factor that governing the efficiency of foliar-applied Zn combined with N, P, or K on grain Zn concentration, the magnitude of the increase/decrease in grain Zn (-3.96~5.71 mg kg-1) due to these interactions was much less than the average increases following Zn+K (31.3), Zn+P (18.7), and Zn+N (26.5 mg kg-1) treatments relative to that observed in foliar Zn-only treatment. The combined foliar application of Zn with N, P, or K did not cause any adverse impact on grain yield and other nutritional quality and in some cases slightly increased grain yield and macronutrient concentrations. Grain phytic acid:Zn molar ratios were respectively 52.0%, 53.1%, 43.4% and 63.5% lower in the foliar Zn, Zn+N, Zn+P and Zn+K treatments than in the control treatment. These effects were consistent over four years and across three soil N

Migration and health risks of nonylphenol and bisphenol a in soil-winter wheat systems with long-term reclaimed water irrigation.

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Wang, Shiyu; Liu, Fei; Wu, Wenyong; Hu, Yaqi; Liao, Renkuan; Chen, Gaoting; Wang, Jiulong; Li, Jialin

2018-04-12

Reclaimed water reuse has become an important means of alleviating agricultural water shortage worldwide. However, the presence of endocrine disrupters has roused up considerable attention. Barrel test in farmland was conducted to investigate the migration of nonylphenol (NP) and bisphenol A (BPA) in soil-winter wheat system simulating reclaimed water irrigation. Additionally, the health risks on humans were assessed based on US EPA risk assessment model. The migration of NP and BPA decreased from the soil to the winter wheat; the biological concentration factors (BCFs) of NP and BPA in roots, stems, leaves, and grains all decreased with their added concentrations in soils. The BCFs of NP and BPA in roots were greatest (0.60-5.80 and 0.063-1.45, respectively). The average BCFs of NP and BPA in winter wheat showed negative exponential relations to their concentrations in soil. The amounts of NP and BPA in soil-winter wheat system accounted for 8.99-28.24% and 2.35-4.95%, respectively, of the initial amounts added into the soils. The hazard quotient (HQ) for children and adults ranged between 10 -6 and 1, so carcinogenic risks could be induced by ingesting winter wheat grains under long-term reclaimed water irrigation. Copyright © 2018 Elsevier Inc. All rights reserved.

Electron-beam-induced current study of small-angle grain boundaries in multicrystalline silicon

International Nuclear Information System (INIS)

Chen, J.; Sekiguchi, T.; Xie, R.; Ahmet, P.; Chikyo, T.; Yang, D.; Ito, S.; Yin, F.

2005-01-01

Recombination activity of small-angle grain boundaries (SA GBs) in multicrystalline silicon (mc-Si) was studied by means of electron-beam-induced current (EBIC) technique. In the as-grown mc-Si, the EBIC contrasts of special Σ and random GBs were weak at both 300 and 100 K, whereas those of SA GBs were weak (<3%) at 300 K and strong (30-40%) at 100 K. In the contaminated mc-Si, SA GBs showed stronger EBIC contrast than Σ and R GBs at 300 K. It is indicated that SA GBs possess high density of shallow levels and are easily contaminated with Fe compared to other GBs

Sage-grouse habitat selection during winter in Alberta

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Carpenter, Jennifer L.; Aldridge, Cameron L.; Boyce, Mark S.

2010-01-01

Greater sage-grouse (Centrocercus urophasianus) are dependent on sagebrush (Artemisia spp.) for food and shelter during winter, yet few studies have assessed winter habitat selection, particularly at scales applicable to conservation planning. Small changes to availability of winter habitats have caused drastic reductions in some sage-grouse populations. We modeled winter habitat selection by sage-grouse in Alberta, Canada, by using a resource selection function. Our purpose was to 1) generate a robust winter habitat-selection model for Alberta sage-grouse; 2) spatially depict habitat suitability in a Geographic Information System to identify areas with a high probability of selection and thus, conservation importance; and 3) assess the relative influence of human development, including oil and gas wells, in landscape models of winter habitat selection. Terrain and vegetation characteristics, sagebrush cover, anthropogenic landscape features, and energy development were important in top Akaike's Information Criterionselected models. During winter, sage-grouse selected dense sagebrush cover and homogenous less rugged areas, and avoided energy development and 2-track truck trails. Sage-grouse avoidance of energy development highlights the need for comprehensive management strategies that maintain suitable habitats across all seasons. ?? 2010 The Wildlife Society.

Small vs. large dust grains in transitional disks: do different cavity sizes indicate a planet?. SAO 206462 (HD 135344B) in polarized light with VLT/NACO

Science.gov (United States)

Garufi, A.; Quanz, S. P.; Avenhaus, H.; Buenzli, E.; Dominik, C.; Meru, F.; Meyer, M. R.; Pinilla, P.; Schmid, H. M.; Wolf, S.

2013-12-01

Context. Transitional disks represent a short stage of the evolution of circumstellar material. Studies of dust grains in these objects can provide pivotal information on the mechanisms of planet formation. Dissimilarities in the spatial distribution of small (μm-size) and large (mm-size) dust grains have recently been pointed out. Aims: Constraints on the small dust grains can be obtained by imaging the distribution of scattered light at near-infrared wavelengths. We aim at resolving structures in the surface layer of transitional disks (with particular emphasis on the inner 10-50 AU), thus increasing the scarce sample of high-resolution images of these objects. Methods: We obtained VLT/NACO near-IR high-resolution polarimetric differential imaging observations of SAO 206462 (HD 135344B). This technique allows one to image the polarized scattered light from the disk without any occulting mask and to reach an inner working angle of ~0.1″. Results: A face-on disk is detected in H and Ks bands between 0.1″ and 0.9″. No significant differences are seen between the H and Ks images. In addition to the spiral arms, these new data allow us to resolve for the first time an inner disk cavity for small dust grains. The cavity size (≃28 AU) is much smaller than what is inferred for large dust grains from (sub-)mm observations (39 to 50 AU). This discrepancy cannot be ascribed to any resolution effect. Conclusions: The interaction between the disk and potential orbiting companion(s) can explain both the spiral arm structure and the discrepant cavity sizes for small and large dust grains. One planet may be carving out the gas (and, thus, the small grains) at 28 AU, and generating a pressure bump at larger radii (39 AU), which holds back the large grains. We analytically estimate that, in this scenario, a single giant planet (with a mass between 5 and 15 MJ) at 17 to 20 AU from the star is consistent with the observed cavity sizes. Based on observations collected at the

Morphological characteristics, dry matter production, and nutritional value of winter forage and grains under grazing and split nitrogen fertilization

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Loreno Egidio Taffarel

2017-06-01

Full Text Available Morphological characteristics, dry matter production, and nutritional values of winter forage and grains were evaluated. This study was conducted from April 24, 2012 to November 7, 2013 in the Western Paraná State University (UNIOESTE, Marechal Cândido Rondon, Brazil. Pastures under one grazing and non-grazing conditions were evaluated under 120 kg N ha-1 fertilization split into two 60 kg N ha-1 treatments. Two pastures received 40 kg N ha-1 three times. IPR 126 oat, BRS Tarumã wheat, and IPR 111 triticale were the test crops. Topdressing with 40 or 60 kg N ha-1 did not change morphological characteristics until 60 d after sowing. Pastures under non-grazing that received 120 kg N ha-1 treatments were taller than the controls, whereas those under grazing that received 80 or 120 kg N ha-1 presented with higher leaf production than did the controls. Total average dry matter (DM production in 2012 and 2013 was, respectively, 5,275 kg ha-1 and 6,270 kg ha-1 for oat, 3,166 kg ha-1 and 7,423 kg ha-1 for wheat, and 4,552 kg ha-1 and 7,603 kg ha-1 for triticale. Split N fertilization did not cause differences in the levels of crude protein (CP, neutral detergent fiber (NDF, and acid detergent fiber (ADF in the forage. Nevertheless, increases in in vitro dry matter digestibility (IVDMD were observed in oat and wheat receiving 60 kg N ha-1 during the first graze. IVDMD did not change in oat, wheat, and triticale forages receiving 80 or 120 kg N ha-1 during the second graze. Grazing did not affect the nutritional values of wheat and triticale grains, but reduced those of oat. Therefore, the results of the present study suggest that grazing lengthens the crop cycles, and so allow the staggered sowing of summer crops.

Genetic resources as initial material for developing new soft winter wheat varieties

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В. М. Кір’ян

2016-12-01

Full Text Available Purpose. To estimate genetic resources collection of soft winter wheat plants (new collection accessions of Ustymivka Experimental Station for Plant Production and select initial material for breeding of adaptive, productive and qualitative soft winter wheat varieties. Methods. Field experiment, laboratory testing. Results. The authors pre- sented results of study of over 1000 samples of gene pool of soft winter wheat from 25 countries during 2001–2005 in Ustymivka Experimental Station for Plant Production of Plant Production Institute nd. a. V. Ya. Yuriev, NAAS of Ukraine for a complex of economic traits. More than 400 new sources with high adaptive properties were selected that combine traits of high productivity and high quality of grain, early ripening, resistance to biotic and abiotic fac- tors (the assessment of samples for 16 valuable traits is given. The selected material comes from various agro-cli- matic zones, including zones of unsustainable agriculture. Conclusions. Recommended sources of traits that have breeding value will allow to enrich high-quality assortment of wheat and considerably accelerate breeding process du- ring development of new soft winter wheat varieties.

Variations in grain lipophilic phytochemicals, proteins and resistance to Fusarium spp. growth during grain storage as affected by biological plant protection with Aureobasidium pullulans (de Bary).

Science.gov (United States)

Wachowska, Urszula; Tańska, Małgorzata; Konopka, Iwona

2016-06-16

Modern agriculture relies on an integrated approach, where chemical treatment is reduced to a minimum and replaced by biological control that involves the use of active microorganisms. The effect of the antagonistic yeast-like fungus Aureobasidium pullulans on proteins and bioactive compounds (alkylresorcinols, sterols, tocols and carotenoids) in winter wheat grain and on the colonization of wheat kernels by fungal microbiota, mainly Fusarium spp. pathogens, was investigated. Biological treatment contributed to a slight increase contents of tocols, alkylresorcinols and sterols in grain. At the same time, the variation of wheat grain proteins was low and not significant. Application of A. pullulans enhanced the natural yeast colonization after six months of grain storage and inhibited growth of F. culmorum pathogens penetrating wheat kernel. This study demonstrated that an integrated approach of wheat grain protection with the use of the yeast-like fungus A. pullulans reduced kernel colonization by Fusarium spp. pathogens and increased the content of nutritionally beneficial phytochemicals in wheat grain without a loss of gluten proteins responsible for baking value. Copyright © 2016. Published by Elsevier B.V.

Mechanical weed control in organic winter wheat

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Euro Pannacci

2017-12-01

Full Text Available Three field experiments were carried out in organic winter wheat in three consecutive years (exp. 1, 2005-06; exp. 2, 2006- 07; exp. 3, 2007-08 in central Italy (42°57’ N - 12°22’ E, 165 m a.s.l. in order to evaluate the efficacy against weeds and the effects on winter wheat of two main mechanical weed control strategies: i spring tine harrowing used at three different application times (1 passage at T1, 2 passages at the time T1, 1 passage at T1 followed by 1 passage at T1 + 14 days in the crop sowed at narrow (traditional row spacing (0.15 m; and ii split-hoeing and finger-weeder, alone and combined at T1, in the crop sowed at wider row spacing (0.30 m. At the time T1 winter wheat was at tillering and weeds were at the cotyledons-2 true leaves growth stage. The experimental design was a randomized block with four replicates. Six weeks after mechanical treatments, weed ground cover (% was rated visually using the Braun-Blanquet coverabundance scale; weeds on three squares (0.6×0.5 m each one per plot were collected, counted, weighed, dried in oven at 105°C to determine weed density and weed above-ground dry biomass. At harvest, wheat ears density, grain yield, weight of 1000 seeds and hectolitre weight were recorded. Total weed flora was quite different in the three experiments. The main weed species were: Polygonum aviculare L. (exp. 1 and 2, Fallopia convolvulus (L. Á. Löve (exp. 1 and 3, Stachys annua (L. L. (exp. 1, Anagallis arvensis L. (exp. 2, Papaver rhoeas L. (exp.3, Veronica hederifolia L. (exp. 3. In the winter wheat sowed at narrow rows, 2 passages with spring-tine harrowing at the same time seems to be the best option in order to reconcile a good efficacy with the feasibility of treatment. In wider rows spacing the best weed control was obtained by split hoeing alone or combined with finger-weeder. The grain yield, on average 10% higher in narrow rows, the lower costs and the good selectivity of spring-tine harrowing

Toolbox for Research and Exploration (TREX): Investigations of Fine-Grained Materials on Small Bodies

Science.gov (United States)

Domingue, D. L.; Allain, J.-P.; Banks, M.; Christoffersen, R.; Cintala, M.; Clark, R.; Cloutis, E.; Graps, A.; Hendrix, A. R.; Hsieh, H.;

Adaptive temperature regulation in the little bird in winter: predictions from a stochastic dynamic programming model.

Science.gov (United States)

Brodin, Anders; Nilsson, Jan-Åke; Nord, Andreas

2017-09-01

Several species of small birds are resident in boreal forests where environmental temperatures can be -20 to -30 °C, or even lower, in winter. As winter days are short, and food is scarce, winter survival is a challenge for small endothermic animals. A bird of this size will have to gain almost 10% of its lean body mass in fat every day to sustain overnight metabolism. Birds such as parids (titmice and chickadees) can use facultative hypothermia, a process in which body temperature is actively down-regulated to a specific level, to reduce heat loss and thus save energy. During cold winter nights, these birds may decrease body temperature from the normal from 42 ° down to 35 °C, or even lower in some species. However, birds are unable to move in this deep hypothermic state, making it a risky strategy if predators are around. Why, then, do small northern birds enter a potentially dangerous physiological state for a relatively small reduction in energy expenditure? We used stochastic dynamic programming to investigate this. Our model suggests that the use of nocturnal hypothermia at night is paramount in these biomes, as it would increase winter survival for a small northern bird by 58% over a winter of 100 days. Our model also explains the phenomenon known as winter fattening, and its relationship to thermoregulation, in northern birds.

Donor of winter rye short stem (Secale cereale L. Gnom 1

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В. В. Скорик

2013-08-01

Full Text Available The article proves that the genetic cluster analysis using of parents – offspring system at the period of 38 generations of directional intentional selection to short stem, the height of winter rye plants has been reduced less than 90 cm with simultaneously productivity integral components increasing. Directional selection on parent plants short stem has revealed pleiotropic effects to increasing averages of productivity yield capacity, spike length, flowers number, grains, and short stem and simultaneously its productivity reducing, plant and weight reducing of 100 direct descendants grains. Plant height donor of short stem Gnome 1 has been controlled prevailing by genetic factors and has been less influenced by environmental conditions. Selection by enlargement of elite plants grains has predetermined genetically increasing of the average height of families in the next generation without the concept selection requirements satisfaction. Therefore, the directed selections, by the structural analysis results, are annually held in two phases, first – to the expressed short stem and then among of them – to the high weight of 100 grains per plant and desirable productivity elements. A creative dominant short stem donor with stems up to 90 cm and a weight of 100 grains per plant more than 4.0 g has been made. A short stem spike shortness donor Dwarf 1possesses a significant reserve of common genetic mutation of quantitative characteristics, which can be used by direct and indirect selection. This population has been represented by its large amount, in order to enhance capabilities of directional selection plants short stem providing with the desired productivity components during the studying. Informative additive genetic cluster analysis is high. Plants productivity is considered to be extremely complicated selection characteristics, including many component constituents parts related genetically. One of these traits changing inevitably causes

Frequent Occupational Exposure to Fusarium Mycotoxins of Workers in the Swiss Grain Industry

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Hélène Niculita-Hirzel

2016-12-01

Full Text Available Type B trichotecens such as deoxynivalenol (DON, 3-acetyldeoxynivalenol (3-ADON, 15-acetyldeoxynivalenol (15-ADON, nivalenol (NIV and zearalenone (ZEN are mycotoxins contaminating wheat and wheat dust. Mycotoxins are toxic upon ingestion and considered potentially toxic when inhaled. Whereas dietary exposure to mycotoxins is controlled in food, data on occupational exposure by inhalation by grain workers are scarce. The objectives of this study were to determine the incidence of DON, 3-ADON, 15-ADON, NIV and ZEN in aerosols generated during grain harvesting and unloading and the risk of exposure of grain workers. Aerosols were collected during the threshing of 78 winter wheat fields and grain unloading of 59 grain lots in six grain terminals in the Vaud region (Switzerland. The samples represented the diversity of the winter wheat cultivar and of the farming system (88 treated with fungicides, 46 untreated. Using a HPLC MS/MS method developed to quantify mycotoxins in aerosols, we report that the mycotoxin content of aerosols was not affected by the wheat cultivars or farming system, but that the incidence of the mycotoxins differed between activities. While wheat harvesting generated on average 28, 20 and 1 ng·m−3 of DON, NIV and ZEN, respectively, grain unloading generated 53, 46 and 4 ng·m−3. Personal sampling revealed that working in a cab was an efficient protective measure. However, it was not sufficient to avoid chronic exposure to multiple mycotoxins. The most exposed activity was the cleaning, exposing workers to DON, NIV and ZEN at concentrations as high as 65, 59 and 3 ng·m−3. These data provide valuable information for future studies of mycotoxin toxicity at relevant concentrations on respiratory health.

Production and evaluation of dwarf and semi-dwarf winter wheat mutants

International Nuclear Information System (INIS)

Barabas, Z.; Kertesz, Z.

1984-01-01

A special research programme for evolving and evaluating dwarf wheat forms resistant to lodging was carried out at the Cereal Research Institute, Wheat Division, Szeged, Hungary. Seed lots of the two tall winter wheat varieties Jubilejnaya 50 and Partizanka were exposed to gamma ray of 60 Co. With irradiation of 15000 rad 60 Co all of M 1 plants grown in the field were almost totally destroyed in 1980 and about 50% in 1982. In the greenhouse the number of lost M 1 plants was insignificant. Only a small number of plants died both in the greenhouse and in the field when they were irradiated with 5000 rad. A treatment with this lower dose of irradiation probably may help the breeders in selection for winter hardiness. 97 dwarf wheat lines already established were analysed for height character by a top cross method using the variety Jubilejnaya 50 as a tester. Height data of the simultaneously grown parental as well as the F 1 and F 2 offsprings indicated that the majority of them were recessive, except 3 cases where dominant or semi-dominant dwarfism was observed. Noteworthy is the Mx 158 a new semi-dwarf variety candidate, 60-65 cm in height at normal stand and resistant to all the main diseases here (powdery mildew and rusts). Its grain and protein production per unit area is also very good. Some genetically lesser-known dwarf sources were investigated in a complete crossing diallel test. (author)

Effects of climatic changes upon the variability of some productivity characters in winter triticale (X Triticosecale Wittm.

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Ionuț RACZ

2017-05-01

Full Text Available The global acceleration warm conditions determine an additional stress for plant growth and development stages with a high impact on plant grain yield performances. During five experimental years the climatic conditions varied quite a lot so that the main productivity elements: the number of grains/spike, weight of grains per spike and number of spikes per square meter had different values which influencing final grain yield. Analyzing the relationship between rainfall/temperature and grain yield, including its components, can be observed a strong relation between those especially in the first growth stages (from plant emergence and vegetative restarting in early spring. Climatic conditions have manifested an important influence also in the last phenophases of winter triticale plant with a negative influence on grain yield. Being a process of long duration, grain yield formation is strongly affected by temperature (r=0.89 and rainfall conditions (r=0.45.

Diet and gut morphology of male mallards during winter in North Dakota

Science.gov (United States)

Olsen, R.E.; Cox, R.R.; Afton, A.D.; Ankney, C.D.

2011-01-01

A free-ranging Mallard (Anas platyrhynchos) population was investigated during winter (December-January 1996-1999) below the Garrison Dam, North Dakota, USA, to relate diet to gut morphology variation in males. Four explanatory variables (fish consumption, male age, winter, and body size) were evaluated as to whether they influenced five response variables associated with gut characteristics of Mallards. Response variables were lower gastro-intestinal tract mass (LGIT), dry liver mass, dry gizzard mass, small intestine length, and ceca length. Diets of Mallards were comprised primarily of Rainbow Smelt (Osmerus mordax) and concomitantly variation in gizzard mass was small. LGIT mass of juveniles was larger than that of adults, greater for those that consumed fish, and greater during the coldest and snowiest winter. Liver mass and small intestine length of Mallards that consumed fish were greater than those that did not. Mallards may maintain lengthy intestines to increase digestive efficiency. Gut size variation was not entirely attributable to dietary composition but also influenced by body size and environmental conditions such that over-winter survival is maximized.

Variability of yield traits and disease resistance in winter triticale genetic resources accessions

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Wanda Kociuba

2014-07-01

Full Text Available A systematic gathering of winter triticale accessions was started in Poland in 1982 by the Institute of Genetics, Breeding and Seed Science at the Agricultural University in Lublin (at present its name is: Institute of Genetics, Breeding and Plant Biotechnology at the University of Life Sciences in Lublin. First, breeding lines obtained in local breeding stations were gathered. Next, accessions were imported from the following world gene banks: Beltsville, Gatersleben, and VIR. Interesting hybrid materials obtained in research centers were also included in the collection. Now, the collection includes 2349 accessions (1329 of winter triticale and 1020 of spring triticale. The evaluation is conducted in a 4-year cycle of field experiments using the same methods. The gathered accessions represent a large range of variability of both morphological and commercial traits. The large differentiation of accessions especially concerns traits such as: plant height, number and weight of grains per spi- ke, protein content in grain, field resistance to powdery mildew, brown rust and leaf and spike diseases.

The genome of Diuraphis noxia, a global aphid pest of small grains.

Science.gov (United States)

Nicholson, Scott J; Nickerson, Michael L; Dean, Michael; Song, Yan; Hoyt, Peter R; Rhee, Hwanseok; Kim, Changhoon; Puterka, Gary J

2015-06-05

The Russian wheat aphid, Diuraphis noxia Kurdjumov, is one of the most important pests of small grains throughout the temperate regions of the world. This phytotoxic aphid causes severe systemic damage symptoms in wheat, barley, and other small grains as a direct result of the salivary proteins it injects into the plant while feeding. We sequenced and de novo assembled the genome of D. noxia Biotype 2, the strain most virulent to resistance genes in wheat. The assembled genomic scaffolds span 393 MB, equivalent to 93% of its 421 MB genome, and contains 19,097 genes. D. noxia has the most AT-rich insect genome sequenced to date (70.9%), with a bimodal CpG(O/E) distribution and a complete set of methylation related genes. The D. noxia genome displays a widespread, extensive reduction in the number of genes per ortholog group, including defensive, detoxification, chemosensory, and sugar transporter groups in comparison to the Acyrthosiphon pisum genome, including a 65% reduction in chemoreceptor genes. Thirty of 34 known D. noxia salivary genes were found in this assembly. These genes exhibited less homology with those salivary genes commonly expressed in insect saliva, such as glucose dehydrogenase and trehalase, yet greater conservation among genes that are expressed in D. noxia saliva but not detected in the saliva of other insects. Genes involved in insecticide activity and endosymbiont-derived genes were also found, as well as genes involved in virus transmission, although D. noxia is not a viral vector. This genome is the second sequenced aphid genome, and the first of a phytotoxic insect. D. noxia's reduced gene content of may reflect the influence of phytotoxic feeding in shaping the D. noxia genome, and in turn in broadening its host range. The presence of methylation-related genes, including cytosine methylation, is consistent with other parthenogenetic and polyphenic insects. The D. noxia genome will provide an important contrast to the A. pisum genome and

The Triticeae Toolbox: Combining Phenotype and Genotype Data to Advance Small-Grains Breeding

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Victoria C. Blake

2016-07-01

Full Text Available The Triticeae Toolbox (; T3 is the database schema enabling plant breeders and researchers to combine, visualize, and interrogate the wealth of phenotype and genotype data generated by the Triticeae Coordinated Agricultural Project (TCAP. T3 enables users to define specific data sets for download in formats compatible with the external tools TASSEL, Flapjack, and R; or to use by software residing on the T3 server for operations such as Genome Wide Association and Genomic Prediction. New T3 tools to assist plant breeders include a Selection Index Generator, analytical tools to compare phenotype trials using common or user-defined indices, and a histogram generator for nursery reports, with applications using the Android OS, and a Field Plot Layout Designer in development. Researchers using T3 will soon enjoy the ability to design training sets, define core germplasm sets, and perform multivariate analysis. An increased collaboration with GrainGenes and integration with the small grains reference sequence resources will place T3 in a pivotal role for on-the-fly data analysis, with instant access to the knowledge databases for wheat and barley. T3 software is available under the GNU General Public License and is freely downloadable.

Reduced irrigation increases the water use efficiency and productivity of winter wheat-summer maize rotation on the North China Plain.

Science.gov (United States)

Wang, Yunqi; Zhang, Yinghua; Zhang, Rui; Li, Jinpeng; Zhang, Meng; Zhou, Shunli; Wang, Zhimin

2018-03-15

The groundwater table has fallen sharply over the last 30years on the North China Plain, resulting in a shortage of water for winter wheat irrigation. Reducing irrigation may be an important strategy to maintain agricultural sustainability in the region; however, few studies have evaluated the transition from conventional irrigation management practices to reduced irrigation management practices in the winter wheat-summer maize rotation system. Here, we compare the yield, water consumption, and water use efficiency of winter wheat-summer maize rotation under conventional irrigation and reduced irrigation on the North China Plain from 2012 to 2015. Reducing irrigation decreased the yield but increased the water use efficiency and significantly advanced the harvest date of winter wheat. As a result, the summer maize sowing date advanced significantly, and the flowering date subsequently advanced 2-8days, thus extending the summer maize grain-filling stage. Therefore, the yield and water use efficiency of summer maize were higher under reduced irrigation than conventional irrigation, which compensated for the winter wheat yield loss under reduced irrigation. In addition, under reduced irrigation from 2012 to 2015, the yield and water use efficiency advantage of the winter wheat-summer maize rotation ranged from 0.0 to 9.7% and from 4.1 to 14.7%, respectively, and water consumption and irrigated water decreased by 20-61mm and 150mm, respectively, compared to conventional irrigation. Overall, the reduced irrigation management practice involving no irrigation after sowing winter wheat, and sowing summer maize on June 7 produced the most favorable grain yield with superb water use efficiency in the winter wheat-summer maize rotation. This study indicates that reducing irrigation could be an efficient means to cope with water resource shortages while maintaining crop production sustainability on the North China Plain. Copyright © 2017. Published by Elsevier B.V.

Winter wheat response to irrigation, nitrogen fertilization, and cold hazards in the Community Land Model 5

Science.gov (United States)

Lu, Y.

2017-12-01

Winter wheat is a staple crop for global food security, and is the dominant vegetation cover for a significant fraction of earth's croplands. As such, it plays an important role in soil carbon balance, and land-atmosphere interactions in these key regions. Accurate simulation of winter wheat growth is not only crucial for future yield prediction under changing climate, but also for understanding the energy and water cycles for winter wheat dominated regions. A winter wheat growth model has been developed in the Community Land Model 4.5 (CLM4.5), but its responses to irrigation and nitrogen fertilization have not been validated. In this study, I will validate winter wheat growth response to irrigation and nitrogen fertilization at five winter wheat field sites (TXLU, KSMA, NESA, NDMA, and ABLE) in North America, which were originally designed to understand winter wheat response to nitrogen fertilization and water treatments (4 nitrogen levels and 3 irrigation regimes). I also plan to further update the linkages between winter wheat yield and cold hazards. The previous cold damage function only indirectly affects yield through reduction on leaf area index (LAI) and hence photosynthesis, such approach could sometimes produce an unwanted higher yield when the reduced LAI saved more nutrient in the grain fill stage.

Calculation of accurate small angle X-ray scattering curves from coarse-grained protein models

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Stovgaard Kasper

2010-08-01

Full Text Available Abstract Background Genome sequencing projects have expanded the gap between the amount of known protein sequences and structures. The limitations of current high resolution structure determination methods make it unlikely that this gap will disappear in the near future. Small angle X-ray scattering (SAXS is an established low resolution method for routinely determining the structure of proteins in solution. The purpose of this study is to develop a method for the efficient calculation of accurate SAXS curves from coarse-grained protein models. Such a method can for example be used to construct a likelihood function, which is paramount for structure determination based on statistical inference. Results We present a method for the efficient calculation of accurate SAXS curves based on the Debye formula and a set of scattering form factors for dummy atom representations of amino acids. Such a method avoids the computationally costly iteration over all atoms. We estimated the form factors using generated data from a set of high quality protein structures. No ad hoc scaling or correction factors are applied in the calculation of the curves. Two coarse-grained representations of protein structure were investigated; two scattering bodies per amino acid led to significantly better results than a single scattering body. Conclusion We show that the obtained point estimates allow the calculation of accurate SAXS curves from coarse-grained protein models. The resulting curves are on par with the current state-of-the-art program CRYSOL, which requires full atomic detail. Our method was also comparable to CRYSOL in recognizing native structures among native-like decoys. As a proof-of-concept, we combined the coarse-grained Debye calculation with a previously described probabilistic model of protein structure, TorusDBN. This resulted in a significant improvement in the decoy recognition performance. In conclusion, the presented method shows great promise for

Winter cover crops as a best management practice for reducing nitrogen leaching

Science.gov (United States)

Ritter, W. F.; Scarborough, R. W.; Chirnside, A. E. M.

1998-10-01

The role of rye as a winter cover crop to reduce nitrate leaching was investigated over a three-year period on a loamy sand soil. A cover crop was planted after corn in the early fall and killed in late March or early April the following spring. No-tillage and conventional tillage systems were compared on large plots with irrigated corn. A replicated randomized block design experiment was conducted on small plots to evaluate a rye cover crop under no-tillage and conventional tillage and with commercial fertilizer, poultry manure and composted poultry manure as nitrogen fertilizer sources. Nitrogen uptake by the cover crop along with nitrate concentrations in groundwater and the soil profile (0-150 cm) were measured on the large plots. Soil nitrate concentrations and nitrogen uptake by the cover crop were measured on the small plots. There was no significant difference in nitrate concentrations in the groundwater or soil profile with and without a cover crop in either no-tillage or conventional tillage. Annual amounts of nitrate-N leached to the water-table varied from 136.0 to 190.1 kg/ha in 1989 and from 82.4 to 116.2 kg/ha in 1991. Nitrate leaching rates were somewhat lower with a cover crop in 1989, but not in 1990. There was no statistically significant difference in corn grain yields between the cover crop and non-cover crop treatments. The planting date and adequate rainfall are very important in maximizing nitrogen uptake in the fall with a rye cover crop. On the Delmarva Peninsula, the cover crop should probably be planted by October 1 to maximize nitrogen uptake rates in the fall. On loamy sand soils, rye winter cover crops cannot be counted on as a best management practice for reducing nitrate leaching in the Mid-Atlantic states.

Exposure to grain dust and microbial components in the Norwegian grain and compound feed industry.

Science.gov (United States)

Halstensen, Anne Straumfors; Heldal, Kari Kulvik; Wouters, Inge M; Skogstad, Marit; Ellingsen, Dag G; Eduard, Wijnand

2013-11-01

The aim of this study was to extensively characterize grain workers' personal exposure during work in Norwegian grain elevators and compound feed mills, to identify differences in exposures between the workplaces and seasons, and to study the correlations between different microbial components. Samples of airborne dust (n = 166) were collected by full-shift personal sampling during work in 20 grain elevators and compound feed mills during one autumn season and two winter seasons. The personal exposure to grain dust, endotoxins, β-1→3-glucans, bacteria, and fungal spores was quantified. Correlations between dust and microbial components and differences between workplaces and seasons were investigated. Determinants of endotoxin and β-1→3-glucan exposure were evaluated by linear mixed-effect regression modeling. The workers were exposed to an overall geometric mean of 1.0mg m(-3) inhalable grain dust [geometric standard deviation (GSD) = 3.7], 628 endotoxin units m(-3) (GSD = 5.9), 7.4 µg m(-3) of β-1→3-glucan (GSD = 5.6), 21 × 10(4) bacteria m(-3) (GSD = 7.9) and 3.6 × 10(4) fungal spores m(-3) (GSD = 3.4). The grain dust exposure levels were similar across workplaces and seasons, but the microbial content of the grain dust varied substantially between workplaces. Exposure levels of all microbial components were significantly higher in grain elevators compared with all other workplaces. The grain dust exposure was significantly correlated (Pearson's r) with endotoxin (rp = 0.65), β-1→3-glucan (rp = 0.72), bacteria (rp = 0.44) and fungal spore (rp = 0.48) exposure, whereas the explained variances were strongly dependent on the workplace. Bacteria, grain dust, and workplace were important determinants for endotoxin exposure, whereas fungal spores, grain dust, and workplace were important determinants for β-1→3-glucan exposure. Although the workers were exposed to a relatively low mean dust level, the microbial exposure was high. Furthermore, the

Economical effectiveness of fungal diseases control of winter wheat in 2000-2008

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Anna Jaczewska-Kalicka

2009-01-01

Full Text Available Winter wheat is a very susceptible species to infection by pathogenic fungi requires the application of plant protection products. Their effectiveness and profitability of application depend on numerous factors. The most important of them are: weather and environmental conditions, managing and organisation of production, the intensity of oc-currence and harmfulness of occurring pathogenes, the amount of obtained yield, costs of protection and grain selling prices. Presented research results are derived from plot ex-periments conducted in the Field Experimental Station IOR-PIB Grodzisk Mazowiecki, on the fields of Agricultural Experimental Station SGGW Chylice, mazowieckie voivode-ship, in 2000-2008 on winter wheat. A high differentiation was stated in profitability of applying particular fungicides, as well as considerable differences between particular vegetative seasons of winter wheat cultivation. In each year, except 2000, protection treatments were profitable, in spite of high costs being on average 10% of the value of protected crop.

Summer fallow soil management - impact on rainfed winter wheat

DEFF Research Database (Denmark)

Li, Fucui; Wang, Zhaohui; Dai, Jian

2014-01-01

Summer fallow soil management is an important approach to improve soil and crop management in dryland areas. In the Loess Plateau regions, the annual precipitation is low and varies annually and seasonally, with more than 60% concentrated in the summer months from July to September, which...... is the summer fallow period in the winter wheat-summer fallow cropping system. With bare fallow in summer as a control, a 3-year location-fixed field experiment was conducted in the Loess Plateau to investigate the effects of wheat straw retention (SR), green manure (GM) planting, and their combination on soil...... water retention (WR) during summer fallow, winter wheat yield, and crop water use and nitrogen (N) uptake. The results showed that SR increased soil WR during summer fallow by 20 mm on average compared with the control over 3 experimental years but reduced the grain yield by 8% in the third year...

The effect of nitrogen fertilizing and fungicide application on the yield and selected parameters of grain quality of winter wheat

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Alena Bezdíčková

2007-01-01

Full Text Available In 2001–2004 an influence of gradually increased portions of nitrogen (100–130–160 kg/N.ha–1 applied on the wheat variety Ebi in combination with the modified fungicidal protection in the yield and the selected quality grain parameters were observed within the small-plot field trials. Nitrogenous fertilizers according to the amount of nitrogen contained were applied in 2–4 terms during vegetation in regeneration (55kg/N.ha–1, 1st production (45kg/N.ha–1, 2nd production (30kg/N.ha–1 and qualitative portion (30kg/N.ha–1. The fungicidal protection was based on the equal treatment in the phase of BBCH 37 and with regard to the varieties different treatment in the phase of BBCH 55. The dependence on the year was proved at all observed parameters. Higher intensity of nitrogenous fertilization had no decisive impact on the yields. From the point of view of increased yields, the second production nitrogenous fertilization had the strongest impact; it increased the grain yields by 0.084–0.461 t./ha–1. Higher intensity of nitrogenous fertilization positively influenced the baker’s grain quality. The increased portions of nitrogen decisively increased the volume of N-substances in all trial years. The second production nitrogenous fertilization increased the N-substances volume from 0.1 to 0.8%. Qualitative additional fertilization increased their volume from 0.26 to 1.38%. Higher N portions increased sedimentation in most cases. The falling number was not considerably influenced. The mechanical grain qualities (volume weight, number full grains, and GTW were relatively less influenced than the baker’s quality by the nitrogenous fertilization. The application of fungicides positively influenced not only the yields but also mechanical qualities of the grain, i.e. volume weight, thousand grains weight and portion of Full grains. On the contrary the baker’s quality was not decisively influenced. It was proved that the decisive

Sputtering of nano-grains by energetic ions

CERN Document Server

Bringa, E M

2002-01-01

Sputtering from grains with a size of tens of nanometers is important in a number of astrophysical environments having a variety of plasma properties and can have applications in nano-technology. Since energy deposition by incident ions or electrons can create 'hot' regions in a small grain, thermal spike (TS) models have been applied to estimate the sputtering. The excitations produced by a fast ion are often assumed to form a 'hot' cylindrical track. In this paper we use molecular dynamics (MD) calculations to describe the energy transport and sputtering due to the creation of a 'hot' track in a grain with one quarter million atoms. We show the enhancement due to grain size and find that TS models work over a limited range of excitation densities. Discrepancies of several orders of magnitude are found when comparing our MD results for sputtering of small dust grains to those obtained by the astrophysical community using spike models.

Winter climate limits subantarctic low forest growth and establishment.

Science.gov (United States)

Harsch, Melanie A; McGlone, Matt S; Wilmshurst, Janet M

2014-01-01

Campbell Island, an isolated island 600 km south of New Zealand mainland (52 °S, 169 °E) is oceanic (Conrad Index of Continentality  =  -5) with small differences between mean summer and winter temperatures. Previous work established the unexpected result that a mean annual climate warming of c. 0.6 °C since the 1940's has not led to upward movement of the forest limit. Here we explore the relative importance of summer and winter climatic conditions on growth and age-class structure of the treeline forming species, Dracophyllum longifolium and Dracophyllum scoparium over the second half of the 20th century. The relationship between climate and growth and establishment were evaluated using standard dendroecological methods and local climate data from a meteorological station on the island. Growth and establishment were correlated against climate variables and further evaluated within hierarchical regression models to take into account the effect of plot level variables. Winter climatic conditions exerted a greater effect on growth and establishment than summer climatic conditions. Establishment is maximized under warm (mean winter temperatures >7 °C), dry winters (total winter precipitation <400 mm). Growth, on the other hand, is adversely affected by wide winter temperature ranges and increased rainfall. The contrasting effect of winter warmth on growth and establishment suggests that winter temperature affects growth and establishment through differing mechanisms. We propose that milder winters enhance survival of seedlings and, therefore, recruitment, but increases metabolic stress on established plants, resulting in lower growth rates. Future winter warming may therefore have complex effects on plant growth and establishment globally.

Sources of Nitrogen for Winter Wheat in Organic Cropping Systems

DEFF Research Database (Denmark)

Petersen, Søren O; Schjønning, Per; Olesen, Jørgen E

2013-01-01

mineralizable N (PMN), microbial biomass N (MBN)] were monitored during two growth periods; at one site, biomass C/N ratios were also determined. Soil for labile N analysis was shielded from N inputs during spring application to isolate cumulated system effects. Potentially mineralizable N and MBN were...... explained 76 and 82% of the variation in grain N yields in organic cropping systems in 2007 and 2008, showing significant effects of, respectively, topsoil N, depth of A horizon, cumulated inputs of N, and N applied to winter wheat in manure. Thus, soil properties and past and current management all......In organic cropping systems, legumes, cover crops (CC), residue incorporation, and manure application are used to maintain soil fertility, but the contributions of these management practices to soil nitrogen (N) supply remain obscure. We examined potential sources of N for winter wheat (Triticum...

Updated stomatal flux and flux-effect models for wheat for quantifying effects of ozone on grain yield, grain mass and protein yield.

Science.gov (United States)

Grünhage, Ludger; Pleijel, Håkan; Mills, Gina; Bender, Jürgen; Danielsson, Helena; Lehmann, Yvonne; Castell, Jean-Francois; Bethenod, Olivier

2012-06-01

Field measurements and open-top chamber experiments using nine current European winter wheat cultivars provided a data set that was used to revise and improve the parameterisation of a stomatal conductance model for wheat, including a revised value for maximum stomatal conductance and new functions for phenology and soil moisture. For the calculation of stomatal conductance for ozone a diffusivity ratio between O(3) and H(2)O in air of 0.663 was applied, based on a critical review of the literature. By applying the improved parameterisation for stomatal conductance, new flux-effect relationships for grain yield, grain mass and protein yield were developed for use in ozone risk assessments including effects on food security. An example of application of the flux model at the local scale in Germany shows that negative effects of ozone on wheat grain yield were likely each year and on protein yield in most years since the mid 1980s. Copyright © 2012 Elsevier Ltd. All rights reserved.

Small Scale Farmers' Knowledge on Grain Losses from Bean ...

African Journals Online (AJOL)

consumers continue to demand higher quality grains, it is increasingly important to prevent contamination and deterioration ... Understanding the insects and microorganism behaviour, and conditions ... restaurants irrespective of category.

Uptake of [14C]triadimenol via grain and root after seed treatment of winter barley with a flowable seed dressing: Influence of soil moisture and sowing date on the distribution of radioactivity and active ingredient content in plant and soil

International Nuclear Information System (INIS)

Schneider, M.

1988-12-01

Winter barley seed of the 'Vogelsander Gold' variety was shown in a total of 7 lysimeters after seed treatment with [benzene ring-U- 14 C]triadimenol in the formulation as [ 14 C]Baytan 075 FS and [ 14 C]Baytan 25 DS at an early (September) and a late date (October). After both dates of sowing, the FS-treated winter barley developed under 3 different soil moisture conditions. The radioactivity and active ingredient contents in plants and soil were recorded until tillering as a function of low, high and natural precipitation after sowing. Details on the uptake of radioactivity via grain and roots were quantitatively and qualitatively studied in two further lysimeters, a pot experiment as well as experiments in the growth chamber. The results are presented and discussed in detail. (orig./MG) [de

Infrared observations of an outburst of small dust grains from the nucleus of Comet P/Halley 1986 III at perihelion

Science.gov (United States)

Gehrz, R. D.; Johnson, C. H.; Magnuson, S. D.; Ney, E. P.; Hayward, T. L.

1995-01-01

A close examination of the 0.7- to 23-micron infrared data base acquired by Gehrz and Ney (1992), suggests that the nucleus of Comet P/Halley 1986 III emitted a burst of small dust grains during a 3-day period commencing within hours of perihelion passage on 1986 February 9.46 UT. The outburst was characterized by significant increases in the coma's grain color temperature T(sub obs), temperature excess (superheat: S = T(sub obs)/T(sub BB)), infrared luminosity, albedo, and 10-micron silicate emission feature strength. These changes are all consistent with the sudden ejection from the nucleus of a cloud of grains with radii of approximately 0.5 micron. This outburst may have produced the dust that was responsible for some of the tail streamers photographed on 1986 February 22 UT. The peak of the dust outburst occurred about 3 days before a pronounced increase in the water production rate measured by the Pioneer Venus Orbiter Ultraviolet Spectrometer. We suggest that jets that release large quantities of small particles may be largely responsible for some of the variable infrared behavior that has been reported for P/Halley and other comets during the past two decades. Such jets may also account for some of the differences IR Type I and IR Type II comets.

Optimizing Winter Wheat Resilience to Climate Change in Rain Fed Crop Systems of Turkey and Iran

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Marta S. Lopes

2018-05-01

Full Text Available Erratic weather patterns associated with increased temperatures and decreasing rainfall pose unique challenges for wheat breeders playing a key part in the fight to ensure global food security. Within rain fed winter wheat areas of Turkey and Iran, unusual weather patterns may prevent attaining maximum potential increases in winter wheat genetic gains. This is primarily related to the fact that the yield ranking of tested genotypes may change from one year to the next. Changing weather patterns may interfere with the decisions breeders make about the ideotype(s they should aim for during selection. To inform breeding decisions, this study aimed to optimize major traits by modeling different combinations of environments (locations and years and by defining a probabilistic range of trait variations [phenology and plant height (PH] that maximized grain yields (GYs; one wheat line with optimal heading and height is suggested for use as a testing line to aid selection calibration decisions. Research revealed that optimal phenology was highly related to the temperature and to rainfall at which winter wheat genotypes were exposed around heading time (20 days before and after heading. Specifically, later winter wheat genotypes were exposed to higher temperatures both before and after heading, increased rainfall at the vegetative stage, and reduced rainfall during grain filling compared to early genotypes. These variations in exposure to weather conditions resulted in shorter grain filling duration and lower GYs in long-duration genotypes. This research tested if diversity within species may increase resilience to erratic weather patterns. For the study, calculated production of a selection of five high yielding genotypes (if grown in five plots was tested against monoculture (if only a single genotype grown in the same area and revealed that a set of diverse genotypes with different phenologies and PHs was not beneficial. New strategies of progeny

Mountain big sagebrush age distribution and relationships on the northern Yellowstone Winter Range

Science.gov (United States)

Carl L. Wambolt; Trista L. Hoffman

2001-01-01

This study was conducted within the Gardiner Basin, an especially critical wintering area for native ungulates utilizing the Northern Yellowstone Winter Range. Mountain big sagebrush plants on 33 sites were classified as large (≥22 cm canopy cover), small (

Grain yield increase in cereal variety mixtures: A meta-analysis of field trials

DEFF Research Database (Denmark)

Kiær, Lars Pødenphant; Skovgaard, Ib; Østergård, Hanne

2009-01-01

on grain yield. To investigate the prevalence and preconditions for positive mixing effects, reported grain yields of variety mixtures and pure variety stands were obtained from previously published variety trials, converted into relative mixing effects and combined using meta-analysis. Furthermore...... as meeting the criteria for inclusion in the meta-analysis; on the other hand, nearly 200 studies were discarded. The accepted studies reported results on both winter and spring types of each crop species. Relative mixing effects ranged from 30% to 100% with an overall meta-estimate of at least 2.7% (p

Association Mapping of Malting Quality Quantitative Trait Loci in Winter Barley: Positive Signals from Small Germplasm Arrays

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Lucía Gutiérrez

2011-11-01

Full Text Available Malting quality comprises one of the most economically relevant set of traits in barley ( L.. It is a complex phenotype, expensive and difficult to measure, that would benefit from a marker-assisted selection strategy. Malting quality is a target of the U.S. Barley Coordinated Agricultural Project (CAP and development of winter habit malting barley varieties is a key objective of the U.S. barley research community. The objective of this work was to detect quantitative trait loci (QTL for malting quality traits in a winter breeding program that is a component of the U.S. Barley CAP. We studied the association between five malting quality traits and 3072 single nucleotide polymorphisms (SNPs from the barley oligonucleotide pool assay (BOPA 1 and 2, assayed in advanced inbred lines from the Oregon State University (OSU breeding program from three germplasm arrays (CAP I, CAP II, and CAP III. After comparing 16 models we selected a structured association model with posterior probabilities inferred from software STRUCTURE (QK approach to use on all germplasm arrays. Most of the marker-trait associations are germplasm- and environment-specific and close to previously mapped genes and QTL relevant for malt and beer quality. We found alleles fixed by random genetic drift, novel unmasked alleles, and genetic-background interaction. In a relatively small population size study we provide strong evidence for detecting true QTL.

CAN A SMALL WINTER RESORT BE MANAGED AND MARKETED LIKE A LARGE ONE: A CASE OF BULGARIAN SKI RESORT BANSKO

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Filip Shabanski

2013-12-01

Full Text Available Throughout the world today there are about 80 countries which practice various winter sports. Regardless of the wide geographical range demand in terms of existing infrastructure is highly concentrated in a few regions of the world. To be competitive ski resorts have to deliver good experiences and excellent value to tourists. Current community officials and destination managers of the Bulgarian ski resort of Bansko believe that the main weakness of this ski centre is the extensive waiting at the bottom gondola station and advocates expansion of the ski runs and lift capacity. The aim of the article is to research the strengths and weaknesses of the resort in regional and world context and to prove that further expansion will not forge a strong emotional connection with visitors and thus will not bring success in destination markets. The methodology used in this article follows three steps: 1 Literature review on the nature of the ski market in the world, as well as factors contributing to effective destination management; 2 International, national and regional data analysis of existing secondary data on winter sports market and 3 Qualitative study carried out with a purposive sample of key informants. The SWOT analysis based on the results of the qualitative study show that touristic shareholders in Bansko should apply an appropriate strategy for small winter resorts by offering a unique product that speaks to the world instead of trying to promote universal broad product for the mass market.

The effect of oleander glycosides on the germination of pollen grains and the mitosis of the generative nucleus in Tradescantia bracteata Small and Allium cepa L.

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J. A. Tarkowska

2015-01-01

Full Text Available The effect of water solution of a mixture of glycosides from oleander (Nerium oleander L. on the germination of pollen grains and on the mitosis of the generative nucleus in Tradescantia bracteata Small and Allium cepa L. has been studied. An inhibition of the germination and of the growth of pollen tubes was observed, proportionally to the concentration of glycosides. The pollen grains of A. cepa are more sensitive. The disturbances in mitosis lead to the formation of two or more uneven-sized doughter nuclei, or to the formation of restitution nuclei. These anomalies are more numerous in T. bracteata. From these results d t appears that pollen grains of A. cepa are characterized by a generally high physiological sensitivity and a small mitotic sensitivity, wheras for T. bracteata the opposite is true.

Winter climate limits subantarctic low forest growth and establishment.

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Melanie A Harsch

Full Text Available Campbell Island, an isolated island 600 km south of New Zealand mainland (52 °S, 169 °E is oceanic (Conrad Index of Continentality  =  -5 with small differences between mean summer and winter temperatures. Previous work established the unexpected result that a mean annual climate warming of c. 0.6 °C since the 1940's has not led to upward movement of the forest limit. Here we explore the relative importance of summer and winter climatic conditions on growth and age-class structure of the treeline forming species, Dracophyllum longifolium and Dracophyllum scoparium over the second half of the 20th century. The relationship between climate and growth and establishment were evaluated using standard dendroecological methods and local climate data from a meteorological station on the island. Growth and establishment were correlated against climate variables and further evaluated within hierarchical regression models to take into account the effect of plot level variables. Winter climatic conditions exerted a greater effect on growth and establishment than summer climatic conditions. Establishment is maximized under warm (mean winter temperatures >7 °C, dry winters (total winter precipitation <400 mm. Growth, on the other hand, is adversely affected by wide winter temperature ranges and increased rainfall. The contrasting effect of winter warmth on growth and establishment suggests that winter temperature affects growth and establishment through differing mechanisms. We propose that milder winters enhance survival of seedlings and, therefore, recruitment, but increases metabolic stress on established plants, resulting in lower growth rates. Future winter warming may therefore have complex effects on plant growth and establishment globally.

Winter Climate Limits Subantarctic Low Forest Growth and Establishment

Science.gov (United States)

Harsch, Melanie A.; McGlone, Matt S.; Wilmshurst, Janet M.

2014-01-01

Campbell Island, an isolated island 600 km south of New Zealand mainland (52°S, 169°E) is oceanic (Conrad Index of Continentality  = −5) with small differences between mean summer and winter temperatures. Previous work established the unexpected result that a mean annual climate warming of c. 0.6°C since the 1940's has not led to upward movement of the forest limit. Here we explore the relative importance of summer and winter climatic conditions on growth and age-class structure of the treeline forming species, Dracophyllum longifolium and Dracophyllum scoparium over the second half of the 20th century. The relationship between climate and growth and establishment were evaluated using standard dendroecological methods and local climate data from a meteorological station on the island. Growth and establishment were correlated against climate variables and further evaluated within hierarchical regression models to take into account the effect of plot level variables. Winter climatic conditions exerted a greater effect on growth and establishment than summer climatic conditions. Establishment is maximized under warm (mean winter temperatures >7 °C), dry winters (total winter precipitation <400 mm). Growth, on the other hand, is adversely affected by wide winter temperature ranges and increased rainfall. The contrasting effect of winter warmth on growth and establishment suggests that winter temperature affects growth and establishment through differing mechanisms. We propose that milder winters enhance survival of seedlings and, therefore, recruitment, but increases metabolic stress on established plants, resulting in lower growth rates. Future winter warming may therefore have complex effects on plant growth and establishment globally. PMID:24691026

Mechanisms of adaptation of small grains to soil acidity

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Đalović Ivica G.

2010-01-01

Full Text Available Acid soils limit crop production on 30-40% of the world's arable land and up to 70% of the world's potentially arable land. Over 60% of the total arable lands in Serbia are acid soils. Soil acidity is determined by hydrogen (H+ in soil solution and it is influenced by edaphic, climatic, and biological factors. Major constraints for plant growth on acid mineral soils are toxic concentrations of mineral elements like Al of H+ and/or low mineral nutrient availability due to low solubility (e.g. P and Mo or low reserves and impaired uptake (e.g. Mg2+ at high H+ concentrations. Aluminum (Al toxicity is primary factor limiting crop production on acid soils. This review examines our current understanding of mechanisms of Al-toxicity, as well as the physiological and genetic basis for Al-toxicity and tolerance. Inhibition of root growth by Al leads to more shallow root systems, which may affect the capacity for mineral nutrient acquisition and increase the risk of drought stress. Of the two principal strategies (tolerance and avoidance of plants for adaptation to adverse soil conditions, the strategy of avoidance is more common for adaptation to acid mineral soils. At the same, the short view of the most important genetics tolerance mechanisms, developed and determined in some small grains genotypes, is showed as well.

Importance of winter pea cv. Maksimirski ozimi in production of the milk on family farms in Croatia

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Darko Uher

2008-12-01

Full Text Available Two year field trials (1999-2001 were carried out to determine the effect of seed winter pea inoculation and nitrogen top-dressing on number and nodule dry weight g/plant of pea root and also on the yield of winter pea cv. Maksimirski ozimi and triticale cv. Clercal mixture. Just before sowing the inoculation of pea seeds was performed by the variety of Rhizobium leguminosarum bv. viciae which is part of the microbial collection of the Department of Microbiology at the Faculty of Agriculture University of Zagreb. The highest total nodule number on pea root (28 nodule/plant was determined on the inoculated variant 2 as well as nodule dry weight (0,175 g/plant. Average pea seed yield were ranging from 1327 kg ha-1 (control up to 1825 kg ha-1 (inoculation. Average triticale grain yield were ranging from 2375 kg ha-1 (control up to 3345 kg ha-1 (nitrogen top-dressing. Average total grain yield of winter peas in mixture triticale were ranging from 3702 kg ha-1 (control up to 5045 kg ha-1 (nitrogen top-dressing. This paper and given results are a humble contribution to the research of pea growth in the Republic of Croatia.

Effect of acicular ferrite formation on grain refinement in the coarse-grained region of heat-affected zone

International Nuclear Information System (INIS)

Wan, X.L.; Wei, R.; Wu, K.M.

2010-01-01

The microstructure of acicular ferrite and its formation for the grain refinement of coarse-grained region of heat-affected zone of high strength low-alloy bainite steels were studied using three-dimensional reconstruction technique. Crystallographic grain size was analyzed by means of electron backscatter diffraction. It was revealed that the microstructure in the coarse-grained region of the heat-affected zone consisted of predominantly bainite packets and a small proportion of acicular ferrite. Acicular ferrite was of lath or plate-like rather than needle or rod-like morphology. Tempering of the coarse-grained region of heat-affected zone showed that the acicular ferrite was more stable than the bainite, indicating that the acicular ferrite was formed prior to bainite. The acicular ferrite laths or plates divided the prior austenite grains into smaller and separate regions, and confining the bainite transformed at lower temperatures in the smaller regions and hence leading to the grain refinement in the coarse-grained region of the heat-affected zone.

Effect of acicular ferrite formation on grain refinement in the coarse-grained region of heat-affected zone

Energy Technology Data Exchange (ETDEWEB)

Wan, X.L.; Wei, R. [Institute of Advanced Steels and Welding Technology, Hubei Provincial Key Laboratory for Systems Science on Metallurgical Processing, Key Laboratory for Ferrous Metallurgy and Resources Utilization of Ministry of Education, Wuhan University of Science and Technology, Wuhan 430081 (China); Wu, K.M., E-mail: wukaiming@wust.edu.cn [Institute of Advanced Steels and Welding Technology, Hubei Provincial Key Laboratory for Systems Science on Metallurgical Processing, Key Laboratory for Ferrous Metallurgy and Resources Utilization of Ministry of Education, Wuhan University of Science and Technology, Wuhan 430081 (China)

2010-07-15

The microstructure of acicular ferrite and its formation for the grain refinement of coarse-grained region of heat-affected zone of high strength low-alloy bainite steels were studied using three-dimensional reconstruction technique. Crystallographic grain size was analyzed by means of electron backscatter diffraction. It was revealed that the microstructure in the coarse-grained region of the heat-affected zone consisted of predominantly bainite packets and a small proportion of acicular ferrite. Acicular ferrite was of lath or plate-like rather than needle or rod-like morphology. Tempering of the coarse-grained region of heat-affected zone showed that the acicular ferrite was more stable than the bainite, indicating that the acicular ferrite was formed prior to bainite. The acicular ferrite laths or plates divided the prior austenite grains into smaller and separate regions, and confining the bainite transformed at lower temperatures in the smaller regions and hence leading to the grain refinement in the coarse-grained region of the heat-affected zone.

Two techniques for mapping and area estimation of small grains in California using Landsat digital data

Science.gov (United States)

Sheffner, E. J.; Hlavka, C. A.; Bauer, E. M.

1984-01-01

Two techniques have been developed for the mapping and area estimation of small grains in California from Landsat digital data. The two techniques are Band Ratio Thresholding, a semi-automated version of a manual procedure, and LCLS, a layered classification technique which can be fully automated and is based on established clustering and classification technology. Preliminary evaluation results indicate that the two techniques have potential for providing map products which can be incorporated into existing inventory procedures and automated alternatives to traditional inventory techniques and those which currently employ Landsat imagery.

Study of grain boundary tunneling in barium-titanate ceramic films

CERN Document Server

Wong, H; Poon, M C

1999-01-01

The temperature and the electric-field dependences of the current-voltage characteristics and the low-frequency noise of barium-titanate ceramic films are studied. An abnormal field dependence is observed in the resistivity of BaTiO sub 3 materials with a small average grain size. In addition, experiments show that the low-frequency noise behaviors are governed by grain-boundary tunneling at room temperature and by trapping-detrapping of grain-boundary states at temperatures above the Curie point. Physical models for the new observations are developed. Results suggest that grain-boundary tunneling of carriers is as important as the double Schottky barrier in the current conduction in BaTiO sub 3 materials with small grain sizes.

Study on physiological characteristics of winter wheat in drought land

International Nuclear Information System (INIS)

Man Huimin; Yu Guohua; Zhan Shumin; Liu Xin; Zhang Guoshu

1995-01-01

Physiological characteristics of winter wheat cultivated in drought land was studied. The results showed that with precipitation of 1 m in the growing period of wheat, it was feasible to use drought cultivation techniques, i.e., increasing the application of P, K and Zn, maintaining the present application of N and increasing the density of wheat plants, to increase the ability of photosynthesis in the parts from the top inter-node above, and a 4900 kg/hm 2 or more of grain yield was obtained. 14 C-assimilate transportation from different parts to grain in drought and irrigating cultivation conditions were 83. 73% and 75.31% respectively. The proline content in flag leaf and the chlorophyll content in the parts from the top inter-node above with drought cultivation were significantly higher than those with normal cultivation

Occurrence of Penicillium verrucosum, ochratoxin A, ochratoxin B and citrinin in on-farm stored winter wheat from the Canadian Great Lakes Region.

Directory of Open Access Journals (Sweden)

Victor Limay-Rios

Full Text Available The occurrence of P. verrucosum and ochratoxin A (OTA were surveyed for 3 and 4 years, respectively. A total of 250 samples was collected from an average of 30 farms during the 2011, 2012, 2013 and 2014 winter seasons. Most storage bins surveyed were typically 11 m high round bins made of corrugated, galvanized steel, with flat-bottoms and conical roofs. Samples of clumped grain contained the most P. verrucosum (p<0.05, n = 10 followed by samples taken from the first load (n = 24, mean = 147±87 CFU/g and last load (n = 17, mean = 101±77 CFU/g. Five grain samples (2.2% tested positive for OTA, citrinin and OTB at concentrations of 14.7±7.9, 4.9±1.9 and 1.2±0.7 ng/g, with only three samples exceeding 5 ng/g. Grain samples positive for OTA were related to moisture resulting from either condensation or migrating moist warm air in the bin or areas where precipitation including snow entered the bin. Bins containing grain and clumps contaminated with OTA were studied in detail. A number of statistically-significant risk factors for OTA contamination were identified. These included 1 grain clumps accumulated around or directly under manhole openings, 2 debris and residue of old grain or grain clumps collected from the bin walls or left on storage floor and augers and 3 grain clumps accumulated around side doors. Even when grain enters storage below the 14.5% threshold of moisture, condensation and moisture migration occurs in hotspots in modern corrugated steel storage bins. Hot spots of OTA contamination were most often in areas affected by moisture migration due to inadequate aeration and exposure to moisture from precipitation or condensation. Further, we found that the nature of the condensation affects the nature and distribution of small and isolated areas with high incidence of toxin contamination and/or P. verrucosum prevalence in the grain bins examined.

Work Tasks as Determinants of Grain Dust and Microbial Exposure in the Norwegian Grain and Compound Feed Industry.

Science.gov (United States)

Straumfors, Anne; Heldal, Kari Kulvik; Wouters, Inge M; Eduard, Wijnand

2015-07-01

The grain and compound feed industry entails inevitable risks of exposure to grain dust and its microbial content. The objective of this study was therefore to investigate task-dependent exposure differences in order to create knowledge basis for awareness and exposure reducing measures in the Norwegian grain and compound feed industry. A total of 166 samples of airborne dust were collected by full-shift personal sampling during work in 20 grain elevators and compound feed mills during one autumn season and two winter seasons. The personal exposure to grain dust, endotoxins, β-1→3-glucans, bacteria, and fungal spores was quantified and used as individual outcomes in mixed models with worker nested in company as random effect and different departments and tasks as fixed effects. The exposure levels were highest in grain elevator departments. Exposure to endotoxins was particularly high. Tasks that represented the highest and lowest exposures varied depending on the bioaerosol component. The most important determinants for elevated dust exposure were cleaning and process controlling. Cleaning increased the dust exposure level by a factor of 2.44 of the reference, from 0.65 to 1.58mg m(-3), whereas process controlling increased the dust exposure level by a factor of 2.97, from 0.65 to 1.93mg m(-3). Process controlling was associated with significantly less grain dust exposure in compound feed mills and the combined grain elevators and compound feed mills, than in grain elevators. The exposure was reduced by a factor of 0.18 and 0.22, from 1.93 to 0.34mg m(-3) and to 0.42mg m(-3), respectively, compared with the grain elevators. Inspection/maintenance, cleaning, and grain rotation and emptying were determinants of higher exposure to both endotoxin and β-1→3-glucans. Seed winnowing was in addition a strong determinant for endotoxin, whereas mixing of animal feed implied higher β-1→3-glucan exposure. Cleaning was the only task that contributed significantly to

An induced mutant of Coastcross 1 Bermudagrass with improved winter hardiness

International Nuclear Information System (INIS)

Burton, G.W.; Constantin, M.J.; Dobson, J.W. Jr.; Hanna, W.W.; Powell, J.B.

1980-01-01

Coastcross 1 bermudagrass, a sterile F 1 hybrid, (Coastal x PI 255445) establishes faster, yields as much dry matter, is 12% more digestible, and gives 30-35% better daily gains and liveweight gains per ha when fed to cattle than does the Coastal clone but fails to develop rhizomes and lacks the winter hardiness of Coastal. To create a winter hardy mutant, 500,000 green stems were exposed to 7000 rad of 60 -Co rays at Oak Ridge, TN June 21, 1971 and were immediately planted at Blairsville, GA where relatively severe winters occur frequently. One of 4 plants surviving the 1971-72 winter was like Coastcross 1 in yield, in vitro dry matter digestibility and appearance in a 3-yr test during mild winters at Tifton, GA. Following the moderate winter of 1976-77, Coastcross 1-M3 yielded more than Coastcross 1 but only about half as much as Coastal. The severe winter of 1977-78 destroyed about 98% of the plants of Coastcross 1 and Coastcross 1-M3 but reduced the stand of Coastal very little. The small gain in winter hardiness by Coastcross 1-M3 suggests that several genes control the winter hardiness of well-established Coastal bermudagrass. (author)

Second generation sequencing and morphological faecal analysis reveal unexpected foraging behaviour by Myotis nattereri (Chiroptera, Vespertilionidae) in winter

DEFF Research Database (Denmark)

Hope, Paul R; Bohmann, Kristine; Gilbert, M. Thomas P.

2014-01-01

BACKGROUND: Temperate winters produce extreme energetic challenges for small insectivorous mammals. Some bat species inhabiting locations with mild temperate winters forage during brief inter-torpor normothermic periods of activity. However, the winter diet of bats in mild temperate locations is ...

Economic analysis of nitrogen fertilization in winter bean plant under no-tillage system

Directory of Open Access Journals (Sweden)

Michelle Traete Sabundjian

2014-09-01

Full Text Available With the expansion and diversity of the no-tillage system, it is necessary to evaluate the economic benefits generated throughout the production cycle, especially those related to remnants of previous crops and nitrogen fertilizer management of succeeding crops. This study aimed to evaluate the economic viability of four cover nitrogen doses on winter bean grain yield grown under no-tillage system after different crops. The experimental design was randomized blocks with four replications, in a 8x4 factorial scheme, with 32 treatments consisting of a combination of crop remnants (mayze; mayze - Azospirillum brasilense; Urochloa ruziziensis; Urochloa ruziziensis - Azospirillum brasilense; mayze + U. ruziziensis; mayze -A. brasilense + U. ruziziensis; mayze + U. ruziziensis - A. brasilense; mayze -A. brasilense + U. ruziziensis - A. brasilense and cover nitrogen doses (0 kg ha-1, 30 kg ha-1, 60 kg ha-1 and 90 kg ha-1. It was possible to conclude that the highest grain yield of winter bean plants irrigated by aspersion was obtained with the use of 90 kg ha-1 of cover nitrogen in succession to Urochloa ruziziensis without the inoculation of Azospirillum brasilense. In order to improve profits, it is recommended to apply 90 kg ha-1 of cover nitrogen to bean crops succeeding the other crops, except for inoculated Urochloa ruziziensis.

Exogenous abscisic acid application during grain filling in winter wheat improves cold tolerance of offspring's seedlings

DEFF Research Database (Denmark)

Li, X.; Cai, J.; Liu, Fulai

2014-01-01

Low temperature seriously depresses seed germination and seedling growth in winter wheat (Triticum aestivum L.). In this study, wheat plants were sprayed with abscisic acid (ABA) and fluridone (inhibitor of ABA biosynthesis) at 19 days after anthesis (DAA) and repeated at 26 DAA. The seeds of those...

Genetic differentiation between sympatric and allopatric wintering populations of Snow Geese

Science.gov (United States)

Humphries, E.M.; Peters, J.L.; Jonsson, J.E.; Stone, R.; Afton, A.D.; Omland, K.E.

2009-01-01

Blackwater National Wildlife Refuge on the Delmarva Peninsula, Maryland, USA has been the wintering area of a small population of Lesser Snow Geese (Chen caerulescens caerulescens; LSGO) since the 1930s. Snow Geese primarily pair in wintering areas and gene flow could be restricted between this and other LSGO wintering populations. Winter pair formation also could facilitate interbreeding with sympatric but morphologically differentiated Greater Snow Geese (C. c. atlantica; GSGO).We sequenced 658 bp of the mitochondrial DNA control region for 68 Snow Geese from East Coast and Louisiana wintering populations to examine the level of genetic differentiation among populations and subspecies. We found no evidence for genetic differentiation between LSGO populations but, consistent with morphological differences, LSGO and GSGO were significantly differentiated. We also found a lack of genetic differentiation between different LSGO morphotypes from Louisiana. We examined available banding data and found the breeding range of Delmarva LSGO overlaps extensively with LSGO that winter in Louisiana, and documented movements between wintering populations. Our results suggest the Delmarva population of LSGO is not a unique population unit apart from Mid-Continent Snow Geese. ?? 2009 by the Wilson Ornithological Society.

Seasonal variation in orthopedic health services utilization in Switzerland: the impact of winter sport tourism.

Science.gov (United States)

Matter-Walstra, Klazien; Widmer, Marcel; Busato, André

2006-03-03

Climate- or holiday-related seasonality in hospital admission rates is well known for many diseases. However, little research has addressed the impact of tourism on seasonality in admission rates. We therefore investigated the influence of tourism on emergency admission rates in Switzerland, where winter and summer leisure sport activities in large mountain regions can generate orthopedic injuries. Using small area analysis, orthopedic hospital service areas (HSAo) were evaluated for seasonality in emergency admission rates. Winter sport areas were defined using guest bed accommodation rate patterns of guest houses and hotels located above 1000 meters altitude that show clear winter and summer peak seasons. Emergency admissions (years 2000-2002, n = 135'460) of local and nonlocal HSAo residents were evaluated. HSAo were grouped according to their area type (regular or winter sport area) and monthly analyses of admission rates were performed. Of HSAo within the defined winter sport areas 70.8% show a seasonal, summer-winter peak hospital admission rate pattern and only 1 HSAo outside the defined winter sport areas shows such a pattern. Seasonal hospital admission rates in HSAo in winter sport areas can be up to 4 times higher in winter than the intermediate seasons, and they are almost entirely due to admissions of nonlocal residents. These nonlocal residents are in general -and especially in winter- younger than local residents, and nonlocal residents have a shorter length of stay in winter sport than in regular areas. The overall geographic distribution of nonlocal residents admitted for emergencies shows highest rates during the winter as well as the summer in the winter sport areas. Small area analysis using orthopedic hospital service areas is a reliable method for the evaluation of seasonality in hospital admission rates. In Switzerland, HSAo defined as winter sport areas show a clear seasonal fluctuation in admission rates of only nonlocal residents, whereas

The long term variation in the ionospheric winter absorption anomaly

International Nuclear Information System (INIS)

Beynon, W.J.G.; Williams, E.R.

1976-01-01

An analysis of vertical incidence absorption data for a mid-latitude station (Freiburg 48 0 N 7.5 0 E) for the 13-year period 1957 to 1969 shows that there is a solar cycle variation both in the number of winter anomaly days and in the magnitude of the absorption anomaly. The magnitude of this variation is discussed in relation to solar X-ray flux and to geomagnetic disturbance. The magnitude of winter anomaly absorption is a maximum in the frequency range 2 to 2.5 MHz. Comparison of the winter anomaly phenomenon at a range of mid-latitude stations suggests that there may be small longitude variation in the magnitude of the phenomenon. (author)

Transfer factor of (90)Sr and (137)Cs to lettuce and winter wheat at different growth stage applications.

Science.gov (United States)

Al Attar, Lina; Al-Oudat, Mohammad; Safia, Bassam; Ghani, Basem Abdul

2015-12-01

The effect of clay soil contamination time on the transfer factors (Fvs) of (137)Cs and (90)Sr was investigated in four different growth stages of winter wheat and lettuce crops. The experiment was performed in an open field using lysimeters. The Fvs were the ratio of the activity concentrations of the radionuclides in crops to those in soil, both as dry weight (Bq kg(-1)). Significant difference of log-Fvs was evaluated using one-way Analysis of Variance (ANOVA). Basically, Fvs of (90)Sr were higher than those of (137)Cs, despite of the application stage or crop' variety. Higher Fvs for both radionuclides were observed for lettuce in comparison to winter wheat. Fvs of (90)Sr showed comparable trends for both crops with enhanced Fvs obtained when contamination occurred in early stages, i.e. 1.20 for lettuce and 0.88 and 0.02 for winter wheat, straw and grains, respectively. Despite the fluctuation noted in the pattern of Fvs for (137)Cs, soil contaminated at the second stage gave the highest Fvs for lettuce and grains, with geometric means of 0.21 and 0.01, respectively. However, wheat-straw showed remarkable increase in Fv for the latest contamination (ripening stage), about 0.06. It could be concluded that soil contamination at early growth stages would represent high radiological risk for the scenarios studied with an exception to (137)Cs in winter wheat-straw which reflected greater hazard at the latest application. Copyright © 2015 Elsevier Ltd. All rights reserved.

Charging properties of a dust grain in collisional plasmas

International Nuclear Information System (INIS)

Khrapak, S.A.; Morfill, G.E.; Khrapak, A.G.; D'yachkov, L.G.

2006-01-01

Charging related properties of a small spherical grain immersed in a collisional plasma are investigated. Asymptotic expressions for charging fluxes, grain surface potential, long range electrostatic potential, and the properties of grain charge fluctuations due to the discrete nature of the charging process are obtained. These analytical results are in reasonable agreement with the available results of numerical modeling

Analysis of Yield and Yield Related Traits Variability of Winter Wheat (Triticum aestivum L. Cv. Izolda and Double Haploid Lines

Directory of Open Access Journals (Sweden)

Kozdój Janusz

2015-12-01

Full Text Available The yield-forming potential of winter wheat is determined by several factors, namely total number of shoots per plant and total number of spikelets per spike. The field experiments were conducted during three vegetation seasons at the Plant Breeding and Acclimatization Institute – National Research Institute (PBAI–NRI, located in Radzików, Poland. The objective of this study was a comparative analysis of the structural yield-forming factor levels, which determine grain yield per spike and per plant of the DH lines and standard Izolda cultivar. Results indicate that several DH lines showed some differences in tested morphological structures of plant, yield factor levels and in grain yield per spike and per plant in comparison to standard Izolda, regardless of the year. Mean grain yield per plant of DH lines was 26.5% lower in comparison to standard Izolda only in the second year of study. It was caused by a reduction of productive tillers number. Structural yield-forming potential of DH lines was used in 38% and 59% and in case of Izolda in 47% and 61% (the second and the third year of experiment, respectively. The mean grain yield per spike of DH lines was 14.8% lower than Izolda cultivar only in third year of experiment and it was caused by about 12% lower number of grains per spike. Structural yield-forming potential of DH spikes was used in 82.4%, 85.4% and 84.9% and in case of Izolda in 83.8%, 87% and 89.5% (the first, the second and the third year of experiment, respectively. The grain yield per winter wheat plant (both DH lines and standard Izolda was significantly correlated with the number of productive tillers per plant (r = 0.80. The grain yield per winter wheat spike (both DH lines and Izolda cultivar was significantly and highly correlated with the number of grains per spike (r = 0.96, number of fertile spikelets per spike (r = 0.87 and the spike length (r = 0.80. Variation of spike and plant structural yield-forming factors

New NS varieties of six-rowed winter barley

Directory of Open Access Journals (Sweden)

Pržulj Novo

2009-01-01

Full Text Available The paper describes the characteristics of several new NS varieties of winter six-rowed barley released in Serbia between 2004 and 2007. These are Somborac, Ozren, Javor, Novosadski 773, Sremac and Leotar. In the official variety trials in the country, all six of these varieties outyielded the check variety, and the margins were as follows: Somborac - 3.4%, Ozren - 5.0%, Javor - 7.3%, Novosadski 773 - 3.4%, Sremac - 7.4%, and Leotar - 7.2%. Yield levels in absolute terms depended on the variety as well as year. All six-rowed NS varieties headed earlier than the check and had better resistance to lodging than the check has. The test weight of the new varieties was 70.2-73.8 kg/hl and the 1000-grain weight 33.4-50.2 g. The cellulose content was 4.4-4.8%, the fat content 1.4%, and the protein content 13.3-14.6%. The high variability of the new NS varieties of winter six-rowed barley makes it possible to choose the most suitable genotype for each barley-growing area in the country. .

Magnetic properties of atmospheric PMx in a small settlement during heating and non-heating season

Science.gov (United States)

Petrovsky, E.; Kotlik, B.; Zboril, R.; Kapicka, A.; Grison, H.

2012-04-01

Magnetic properties of environmental samples can serve as fast and relatively cheap proxy method to investigate occurrence of iron oxides. These methods are very sensitive in detecting strongly magnetic compounds such as magnetite and maghemite and can reveal concentration and assess grain-size distribution of these minerals. This information can be significant in estimating e.g. the source of pollutants, monitoring pollution load, or investigating seasonal and climatic effects. We studied magnetic properties of PM1, PM2.5 and PM10, collected over 32-48 hours in a small settlement in south Bohemia during heating and non-heating season. The site is rather remote, with negligible traffic and industrial contributions to air pollution. Thus, the suggested seasonal effect should be dominantly due to local (domestic) heating, burning wood or coal. In our contribution we show typical differences in PMx concentration, which is much higher in the winter (heating) sample, accompanied by SEM analyses and magnetic data oriented on concentration and grain-size distribution of magnetite/maghemite particles. While concentration of Fe-oxides does not vary that much, significant seasonal differences were observed in composition and grain-size distribution, reflecting different sources of the dust particles.

Grain size refinement of inconel 718 thermomechanical processing

International Nuclear Information System (INIS)

Okimoto, P.C.

1988-01-01

Inconel 718 is a Ni-Fe precipitation treated superalloy. It presents good thermal fatigue properties when the material has small grain size. The aim of this work is to study the grain size refinement by thermomechanical processing, through observations of the microstructural evolution and the influence of some of the process variables in the final grain size. The results have shown that this refinement occured by static recrystallization. The presence of precipitates have influenced the final grain size if the deformations are below 60%. For greater deformations the grain size is independent of the precipitate distribution in the matrix and tends to a limit size of 5 μm. (author)

Spirit Scans Winter Haven

Science.gov (United States)

2006-01-01

At least three different kinds of rocks await scientific analysis at the place where NASA's Mars Exploration Rover Spirit will likely spend several months of Martian winter. They are visible in this picture, which the panoramic camera on Spirit acquired during the rover's 809th sol, or Martian day, of exploring Mars (April 12, 2006). Paper-thin layers of light-toned, jagged-edged rocks protrude horizontally from beneath small sand drifts; a light gray rock with smooth, rounded edges sits atop the sand drifts; and several dark gray to black, angular rocks with vesicles (small holes) typical of hardened lava lie scattered across the sand. This view is an approximately true-color rendering that combines images taken through the panoramic camera's 753-nanometer, 535-nanometer, and 432-nanometer filters.

Diffusion mechanisms in grain boundaries in solids

International Nuclear Information System (INIS)

Peterson, N.L.

1982-01-01

A critical review is given of our current knowledge of grain-boundary diffusion in solids. A pipe mechanism of diffusion based on the well-established dislocation model seems most appropriate for small-angle boundaries. Open channels, which have atomic configurations somewhat like dislocation cores, probably play a major role in large-angle grain-boundary diffusion. Dissociated dislocations and stacking faults are not efficient paths for grain-boundary diffusion. The diffusion and computer modeling experiments are consistent with a vacancy mechanism of diffusion by a rather well-localized vacancy. The effective width of a boundary for grain-boundary diffusion is about two atomic planes. These general features of grain-boundary diffusion, deduced primarily from experiments on metals, are thought to be equally applicable for pure ceramic solids. The ionic character of many ceramic oxides may cause some differences in grain-boundary structure from that observed in metals, resulting in changes in grain-boundary diffusion behavior. 72 references, 5 figures

On the theory of dynamics of dust grain in plasma

Science.gov (United States)

Stepanenko, A. A.; Krasheninnikov, S. I.

2013-03-01

The dynamics of rotationally symmetric dust grains in plasma embedded in a magnetic field are of concern. The general expressions for forces and torques acting on dust are found. It is shown that dust spinning is determined by torques related to both the Lorentz force (dominant for relatively small grains) and the gyro-motion of plasma particles impinging the grain (which prevails for large grains). The stability of grain spinning is analyzed and it is shown that, for some cases (e.g., oblate spheroid), there is no stable dynamic equilibrium of grain spinning.

Technology transfer for the handling post-harvest of grains at small farmer's level in three villages of the Municipality of La Vega Cundinamarca

International Nuclear Information System (INIS)

Hernandez Hernandez, Jose Eugenio

1999-01-01

The small agricultural producers of La Vega Municipality, in the Cundinamarca Department, the same as most of the rural producers of the country, they have been seeing seriously affected their crops of corn, bean and in general of basic grains, because of the attack of different agents biological considered plagues in the stored grains; as insects, microorganisms, birds and rodents, due to the ignorance of the appropriate techniques for the handling post-harvest of these products already the lack of sure systems of storage and conservation of the same ones. With the co-financing of the Technology National Program Transfer - PRONATTA. The present project developed a methodological model of technology transfer for the handling post-harvest of basic grains; the causes were determined that originated the problem and they thought about several technological alternatives of solution. Among the causes it was the lack of arrangement of the grains after the gathering and the use of systems and storage structures that didn't offer protection to the product, in front of the action of the destructive biological agents, in such a way that they were given training in the handling of the grains, appropriate silos were built, shops were developed with the farmers, to divulge notes, manuals and didactic videos, among others

Winters fuels report

International Nuclear Information System (INIS)

1995-01-01

The outlook for distillate fuel oil this winter is for increased demand and a return to normal inventory patterns, assuming a resumption of normal, cooler weather than last winter. With industrial production expected to grow slightly from last winter's pace, overall consumption is projected to increase 3 percent from last winter, to 3.4 million barrels per day during the heating season (October 1, 1995-March 31, 1996). Much of the supply win come from stock drawdowns and refinery production. Estimates for the winter are from the Energy Information Administration's (EIA) 4th Quarter 1995 Short-Tenn Energy Outlook (STEO) Mid-World Oil Price Case forecast. Inventories in place on September 30, 1995, of 132 million barrels were 9 percent below the unusually high year-earlier level. Inventories of high-sulfur distillate fuel oil, the principal type used for heating, were 13 percent lower than a year earlier. Supply problems are not anticipated because refinery production and the ready availability of imports should be adequate to meet demand. Residential heating off prices are expected to be somewhat higher than last winter's, as the effects of lower crude oil prices are offset by lower distillate inventories. Heating oil is forecast to average $0.92 per gallon, the highest price since the winter of 1992-93. Diesel fuel (including tax) is predicted to be slightly higher than last year at $1.13 per gallon. This article focuses on the winter assessment for distillate fuel oil, how well last year's STEO winter outlook compared to actual events, and expectations for the coming winter. Additional analyses include regional low-sulfur and high-sulfur distillate supply, demand, and prices, and recent trends in distillate fuel oil inventories

Wheat grain mechanical vulnerability to mechanical damage in light of the recent agrophysical research[X-radiation]; Podatnosc ziarna pszenicy na uszkodzenia mechaniczne w swietle dotychczasowych badan agrofizycznych

Energy Technology Data Exchange (ETDEWEB)

Grundas, S [Instytut Agrofizyki Polskiej Akademii Nauk, Lublin (Poland)

1995-07-01

The paper contains basic information on mechanical damage to wheat grains. The most important causes of mechanical damage and some of its effects in manufacturing are discussed. Grain material included 5 varieties of winter wheat and 2 varieties of spring wheat. Internal mechanical damage was examined by X-ray technique; external damage was examined with the colorimeter method. The results obtained were compared with the estimation results of more important processing features of the grain: gluten quantity and quality and grain hardness. (author)

Microdochium nivale and Microdochium majus in seed samples of Danish small grain cereals

DEFF Research Database (Denmark)

Nielsen, L. K.; Justesen, A. F.; Jensen, J. D.

2013-01-01

Microdochium nivale and Microdochium majus are two of fungal species found in the Fusarium Head Blight (FHB) complex infecting small grain cereals. Quantitative real-time PCR assays were designed to separate the two Microdochium species based on the translation elongation factor 1a gene (TEF-1a......) and used to analyse a total of 374 seed samples of wheat, barley, triticale, rye and oat sampled from farmers’ fields across Denmark from 2003 to 2007. Both fungal species were detected in the five cereal species but M. majus showed a higher prevalence compared to M. nivale in most years in all cereal...... species except rye, in which M. nivale represented a larger proportion of the biomass and was more prevalent than M. majus in some samples. Historical samples of wheat and barley from 1957 to 2000 similarly showed a strong prevalence of M. majus over M. nivale indicating that M. majus has been the main...

Winter to winter recurrence of atmospheric circulation anomalies over East Asia and its impact on winter surface air temperature anomalies.

Science.gov (United States)

Zhao, Xia; Yang, Guang

2017-01-01

The persistence of atmospheric circulation anomalies over East Asia shows a winter to winter recurrence (WTWR) phenomenon. Seasonal variations in sea level pressure anomalies and surface wind anomalies display significantly different characteristics between WTWR and non-WTWR years. The WTWR years are characterized by the recurrence of both a strong (weak) anomalous Siberian High and an East Asian winter monsoon over two successive winters without persistence through the intervening summer. However, anomalies during the non-WTWR years have the opposite sign between the current and ensuing winters. The WTWR of circulation anomalies contributes to that of surface air temperature anomalies (SATAs), which is useful information for improving seasonal and interannual climate predictions over East Asia and China. In the positive (negative) WTWR years, SATAs are cooler (warmer) over East Asia in two successive winters, but the signs of the SATAs are opposite in the preceding and subsequent winters during the non-WTWR years.

Performance evaluation of commercial maize hybrids across diverse Terai environments during the winter season in Nepal

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Mahendra Prasad Tripathi

2016-12-01

Full Text Available The hybrid maize cultivars of multinational seed companies are gradually being popular among the farmers in Nepal. This paper reports on research finding of 117 maize hybrids of 20 seed companies assessed for grain yield and other traits at three sites in winter season of 2011 and 2012. The objective of the study was to identify superior maize hybrids suitable for winter time planting in eastern, central and inner Terai of Nepal. Across site analysis of variance revealed that highly significant effect of genotype and genotype × environment interaction (GEI on grain yield of commercial hybrids. Overall, 47 genotypes of 16 seed companies identified as high yielding and stable based on superiority measures. The statistical analysis ranked topmost three genotypes among tested hybrids as P3856 (10515 kg ha-1, Bisco prince (8763 kg ha-1 as well as Shaktiman (8654 kg ha-1 in the first year; and 3022 (8378 kg ha-1, Kirtiman manik (8323 kg ha-1 as well as Top class (7996 kg ha-1 in the second year. It can be concluded that stable and good performing hybrids identified as potential commercial hybrids for general cultivation on similar environments in Nepal.

Fractal dust grains in plasma

International Nuclear Information System (INIS)

Huang, F.; Peng, R. D.; Liu, Y. H.; Chen, Z. Y.; Ye, M. F.; Wang, L.

2012-01-01

Fractal dust grains of different shapes are observed in a radially confined magnetized radio frequency plasma. The fractal dimensions of the dust structures in two-dimensional (2D) horizontal dust layers are calculated, and their evolution in the dust growth process is investigated. It is found that as the dust grains grow the fractal dimension of the dust structure decreases. In addition, the fractal dimension of the center region is larger than that of the entire region in the 2D dust layer. In the initial growth stage, the small dust particulates at a high number density in a 2D layer tend to fill space as a normal surface with fractal dimension D = 2. The mechanism of the formation of fractal dust grains is discussed.

Impact of Solid and Hollow Varieties of Winter and Spring Wheat on Severity of Wheat Stem Sawfly (Hymenoptera: Cephidae) Infestations and Yield and Quality of Grain.

Science.gov (United States)

Szczepaniec, Adrianna; Glover, Karl D; Berzonsky, William

2015-10-01

Wheat stem sawfly (WSS), Cephus cinctus Norton (Hymenoptera: Cephidae), has recently emerged as a key pest of wheat (Triticum aestivum L.) in the Great Plains and Canadian provinces. The expanding impact of WSS has caused considerable economic losses to wheat production. Solid-stem varieties of wheat remain the only effective measure of suppression of WSS, and the goal of this research was to test whether five solid- and hollow-stem varieties of winter and spring wheat reduce survival of WSS in South Dakota. We reported that solid-stem varieties had significantly lower numbers of WSS larvae, and this effect was especially evident when WSS infestation rates exceeded 15%. We also observed that the yield of solid-stem varieties was significantly lower than hollow-stem varieties when the abundance of WSS was low, but not when populations of WSS were relatively high. We did not observe consistent differences in grain quality between solid- and hollow-stem varieties, however, and in case of protein levels of grain, solid-stem wheat varieties performed better than hollow-stem wheat. We conclude that solid-stem varieties of wheat appear to effectively suppress WSS survival, and reduced yield of these varieties is less apparent when populations of C. cinctus are high enough to affect the yield of hollow-stem wheat. This is the first report to describe the effectiveness of solid-stem varieties of wheat on WSS in South Dakota. More research in the state is necessary before more robust conclusions can be drawn. © The Authors 2015. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

MATHEMATICAL MODEL OF GRAIN MICRONIZATION

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V. A. Afanas’ev

2014-01-01

Full Text Available Summary. During micronisation grain moisture evaporates mainly in decreasing drying rate period. Grain layer located on the surface of the conveyor micronisers will be regarded as horizontal plate. Due to the fact that the micronisation process the surface of the grain evaporates little moisture (within 2-7 % is assumed constant plate thickness. Because in the process of micronization grain structure is changing, in order to achieve an exact solution of the equations necessary to take into account changes thermophysical, optical and others. Equation of heat transfer is necessary to add a term that is responsible for the infrared heating. Because of the small thickness of the grain, neglecting the processes occurring at the edge of the grain, that is actually consider the problem of an infinite plate. To check the adequacy of the mathematical model of the process of micronisation of wheat grain moisture content must be comparable to the function of time, obtained by solving the system of equations with the measured experimental data of experience. Numerical solution of a system of equations for the period of decreasing drying rate is feasible with the help of the Maple 14, substituting the values of the constants in the system. Calculation of the average relative error does not exceed 7- 10 %, and shows a good agreement between the calculated data and the experimental values.

[Effects of long-term mixed application of organic and inorganic fertilizers on canopy apparent photosynthesis and yield of winter wheat].

Science.gov (United States)

Zhao, Jun; Dong, Shu-ting; Liu, Peng; Zhang, Ji-wang; Zhao, Bin

2015-08-01

A field experiment was conducted using the winter wheat (Triticum aestivum) variety Shimai 15. The source of organic nitrogen was cow manure, and four fertilization treatments were included, i.e., no N fertilizer application, single application of urea, single application of cow manure, and mixed application of urea and cow manure. The effects of different applications of inorganic and organic nitrogen on canopy apparent photosynthesis (CAP), photosynthetic rate of flag leaves (Pn), leaf area index (LAI), florescence parameters and grain yield of winter wheat were determined. The results showed that urea had the largest effect on the early growth period, as at this stage the CAP, Pn and LAI of the single application of urea were the highest, which was followed by the mixed application and the single application of cow manure. However, 10 days after anthesis, the single application of cow manure and the mixed application delayed the leaf senescence process when compared with the single application of urea. This could be due to the two treatments having higher anti-oxidant enzyme activity and promoting a longer green leaf duration, which could maintain a higher photosynthetic capability. What' s more, the mixed application had a better performance and got the highest grain yield. Consequently, the mixed application of organic and inorganic fertilizers could delay leaf senescence and maintain a better canopy structure and higher photosynthesis capability at the late grain filling stage, which resulted in a higher grain yield.

[Influence of water deficit and supplemental irrigation on nitrogen uptake by winter wheat and nitrogen residual in soil].

Science.gov (United States)

Wang, Zhaohui; Wang, Bing; Li, Shengxiu

2004-08-01

Pot experiment in greenhouse showed that water deficit at all growth stages and supplemental irrigation at tillering stage significantly decreased the nitrogen uptake by winter wheat and increased the mineral N residual (79.8-113.7 mg x kg(-1)) in soil. Supplemental irrigation at over-wintering, jointing or filling stage significantly increased the nitrogen uptake by plant and decreased the nitrogen residual (47.2-60.3 mg x kg(-1)) in soil. But, the increase of nitrogen uptake caused by supplemental irrigation did not always mean a high magnitude of efficient use of nitrogen by plants. Supplemental irrigation at over-wintering stage didn't induce any significant change in nitrogen content of grain, irrigation at filling stage increased the nitrogen content by 20.9%, and doing this at jointing stage decreased the nitrogen content by 19.6%, as compared to the control.

Intersection of mycotoxins from grains to finished baking

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Viera Šottníková

2016-07-01

Full Text Available This work is focused on the evaluation of the content of deoxynivalenol and zearalenone in samples of winter wheat of the following varieties: Sultan, Cubus, Akteur, Seladon, Mulan, Chevalier, Evina, Hewitt, Bohemia, Baletka. The total amount of 10 samples harvested in 2011 and 2012 was evaluated and included variants both treated and untreated against fungal diseases. The samples were adjusted for mycotoxicological determination and subsequently measured by the ELISA method. The content of deoxynivalenol (DON and zearalenone (ZEA was measured in grain, flour and breadrolls in all samples. Out of all samples 43% were found to have positive content of DON and 75% of ZEA. In the treated variants, the average DON content was found to be 115 µg.kg-1 in grain, 77 µg.kg-1 in flour and 97 µg.kg-1 in pastries. In the untreated variants, the average DON content was found to be 208 µg.kg-1 in grain, 103 µg.kg-1 in flour and 128 µg.kg-1 in pastries. Moreover, the average ZEA content in the treated variant was 4.95 µg.kg-1 in grain, 3.38 µg.kg-1 in flour and 4.51 µg.kg-1 in pastries, in the non-treated variant average ZEA content in grain was 3.07 µg.kg-1, 4.97 µg.kg-1 in flour and 2.81 µg.kg-1 in pastries. The maximal acceptable limits given by the valid legislation were not exceeded in any analysed sample. It can be concluded wheat grain grown in the Czech Republic, whether it is treated or untreated by fungicides, is not dangerous for consumers. The content of both mycotoxins is not dependent on each other, and the untreated variant has a slightly higher dependency between DON and ZEA.

Does Wyoming's Core Area Policy Protect Winter Habitats for Greater Sage-Grouse?

Science.gov (United States)

Smith, Kurt T.; Beck, Jeffrey L.; Pratt, Aaron C.

2016-10-01

Conservation reserves established to protect important habitat for wildlife species are used world-wide as a wildlife conservation measure. Effective reserves must adequately protect year-round habitats to maintain wildlife populations. Wyoming's Sage-Grouse Core Area policy was established to protect breeding habitats for greater sage-grouse ( Centrocercus urophasianus). Protecting only one important seasonal habitat could result in loss or degradation of other important habitats and potential declines in local populations. The purpose of our study was to identify the timing of winter habitat use, the extent which individuals breeding in Core Areas used winter habitats, and develop resource selection functions to assess effectiveness of Core Areas in conserving sage-grouse winter habitats in portions of 5 Core Areas in central and north-central Wyoming during winters 2011-2015. We found that use of winter habitats occured over a longer period than current Core Area winter timing stipulations and a substantial amount of winter habitat outside of Core Areas was used by individuals that bred in Core Areas, particularly in smaller Core Areas. Resource selection functions for each study area indicated that sage-grouse were selecting habitats in response to landscapes dominated by big sagebrush and flatter topography similar to other research on sage-grouse winter habitat selection. The substantial portion of sage-grouse locations and predicted probability of selection during winter outside small Core Areas illustrate that winter requirements for sage-grouse are not adequately met by existing Core Areas. Consequently, further considerations for identifying and managing important winter sage-grouse habitats under Wyoming's Core Area Policy are warranted.

Simulation of growing grains under orientation relation - dependent quadruple point dragging

International Nuclear Information System (INIS)

Ito, K

2015-01-01

The growth behaviour of a specified grain embedded in matrix grains, for which the migration mobility of the quadruple points depended on the relation between the orientations of the growing and shrinking grains, was studied using a modified Potts MC-type threedimensional simulation. Large embedded grains continued to grow without being overcome by coarsening matrix grains, whereas small embedded grains disappeared, under the influence of the relative mobilities of the quadruple points, the composition of the matrix grain texture and the width of the grain size distribution of the matrix grains. These results indicate that orientation relation-dependent quadruple point dragging can affect the recrystallization texture during the grain coarsening stage. (paper)

Exogenous lactobacilli mitigate microbial changes associated with grain fermentation in vitro

Science.gov (United States)

Cereal grains are often included in equine diets. Sugars and starch in grains can be digested and absorbed in the small intestine, but a high proportion of grain in the diet can allow starch to reach the hindgut, disturbing the microbial ecology. Streptococci and lactobacilli both catabolize starch ...

Grain-boundary sliding in a TiAl alloy with fine-grained duplex microstructure during 750 deg. C creep

Energy Technology Data Exchange (ETDEWEB)

Peter, D. [Ruhr University Bochum, Institute for Materials, D-44780 Bochum (Germany); Viswanathan, G.B., E-mail: Viswanathan.11@osu.edu [Ruhr University Bochum, Institute for Materials, D-44780 Bochum (Germany) and Department of Materials Science and Engineering, Ohio State University, Columbus, OH 43210 (United States); Wagner, M.F.-X.; Eggeler, G. [Ruhr University Bochum, Institute for Materials, D-44780 Bochum (Germany)

2009-06-15

Constant-load creep experiments at a temperature of 750 deg. C and a nominal stress of 300 MPa were conducted on a fine-grained Ti-45Al-5Nb-0.2B-0.2C (in at.%) alloy with a duplex microstructure. Microstructures before and after creep (accumulated strain: 9.6%) were analyzed using scanning and transmission electron microscopy (SEM and TEM). TEM analysis after creep indicates that the individual microstructural constituents of the fine duplex microstructure, namely, the equiaxed {gamma} and the lamellar {alpha}{sub 2}/{gamma} colonies, undergo varying degrees of deformation and develop various substructures. Lamellar grains deform by dislocation creep. They show clear evidence for dislocation and twin activity. In contrast, only few dislocations are found in the equiaxed grains. We show that the regions with small equiaxed {gamma} grains, representing 65-75 vol.% of the microstructure, deform by grain-boundary sliding.

Grain-boundary sliding in a TiAl alloy with fine-grained duplex microstructure during 750 deg. C creep

International Nuclear Information System (INIS)

Peter, D.; Viswanathan, G.B.; Wagner, M.F.-X.; Eggeler, G.

2009-01-01

Constant-load creep experiments at a temperature of 750 deg. C and a nominal stress of 300 MPa were conducted on a fine-grained Ti-45Al-5Nb-0.2B-0.2C (in at.%) alloy with a duplex microstructure. Microstructures before and after creep (accumulated strain: 9.6%) were analyzed using scanning and transmission electron microscopy (SEM and TEM). TEM analysis after creep indicates that the individual microstructural constituents of the fine duplex microstructure, namely, the equiaxed γ and the lamellar α 2 /γ colonies, undergo varying degrees of deformation and develop various substructures. Lamellar grains deform by dislocation creep. They show clear evidence for dislocation and twin activity. In contrast, only few dislocations are found in the equiaxed grains. We show that the regions with small equiaxed γ grains, representing 65-75 vol.% of the microstructure, deform by grain-boundary sliding.

Thermal transfer and apparent-dose distributions in poorly bleached mortar samples: results from single grains and small aliquots of quartz

International Nuclear Information System (INIS)

Jain, M.; Thomsen, K.J.; Boetter-Jensen, L.; Urray, A.S.

2004-01-01

In the assessment of doses received from a nuclear accident, considerable attention has been paid to retrospective dosimetry using the optically stimulated luminescence (OSL) of heated materials such as bricks and tiles. quartz extracted from these artefacts was heated during manufacture; this process releases all the prior trapped charge and simultaneously sensitises he quartz. Unfortunately unheated materials such as mortar and concrete are ore common in industrial sites and particularly in nuclear installations. These materials are usually exposed to daylight during quarrying and construction, but in general this exposure is insufficient to completely empty (bleach) any geological trapped charge. This leads to a distribution of apparent doses in the sample at the time of construction with only some (if ny) grains exposed to sufficient light to be considered well bleached for SL dosimetry. The challenge in using such materials as retrospective dosemeters is in identifying these well-bleached grains when an accident dose as been superimposed on the original dose distribution. We investigate here, sing OSL, the background dose in three different mortar samples: render, whitewash and inner wall plaster from a building built in 1964. These samples re found to be both poorly bleached and weakly sensitive (only 0.3% of rains giving a detectable dose response). We study thermal transfer in ingle grains of quartz, investigate the grain-size dependence of bleaching n the size range 90-300 μm and compare the dose-distributions obtained rom small aliquots and single-grain procedures. A comparison of three different methods viz. (a) first 5%, (b) probability plot and (c) comparison f internal and external uncertainties, is made for equivalent dose estimation. The results have implications for accident dosimetry, archaeological studies and dating of poorly bleached sediments

Winter is losing its cool

Science.gov (United States)

Feng, S.

2017-12-01

Winter seasons have significant societal impacts across all sectors ranging from direct human health to ecosystems, transportation, and recreation. This study quantifies the severity of winter and its spatial-temporal variations using a newly developed winter severity index and daily temperature, snowfall and snow depth. The winter severity and the number of extreme winter days are decreasing across the global terrestrial areas during 1901-2015 except the southeast United States and isolated regions in the Southern Hemisphere. These changes are dominated by winter warming, while the changes in daily snowfall and snow depth played a secondary role. The simulations of multiple CMIP5 climate models can well capture the spatial and temporal variations of the observed changes in winter severity and extremes during 1951-2005. The models are consistent in projecting a future milder winter under various scenarios. The winter severity is projected to decrease 60-80% in the middle-latitude Northern Hemisphere under the business-as-usual scenario. The winter arrives later, ends earlier and the length of winter season will be notably shorter. The changes in harsh winter in the polar regions are weak, mainly because the warming leads to more snowfall in the high latitudes.

Small grain size zirconium-based coatings deposited by magnetron sputtering at low temperatures

Energy Technology Data Exchange (ETDEWEB)

Jimenez, O., E-mail: omar.jimenez.udg@gmail.com [Departamento de Ingeniería de Proyectos, CUCEI, Universidad de Guadalajara, AP 307, CP 45101 Zapopan, Jal (Mexico); Department of Materials Science and Engineering, The University of Sheffield, Sheffield S1 3JD (United Kingdom); Audronis, M.; Leyland, A. [Department of Materials Science and Engineering, The University of Sheffield, Sheffield S1 3JD (United Kingdom); Flores, M.; Rodriguez, E. [Departamento de Ingeniería de Proyectos, CUCEI, Universidad de Guadalajara, AP 307, CP 45101 Zapopan, Jal (Mexico); Kanakis, K.; Matthews, A. [Department of Materials Science and Engineering, The University of Sheffield, Sheffield S1 3JD (United Kingdom)

2015-09-30

Hard, partly amorphous, ZrTiB(N) coatings were deposited by Physical Vapour Deposition (PVD) onto (111) silicon wafers at low substrate temperatures of 85 and 110 °C using Closed Field Unbalanced Magnetron Sputtering. A segmented rectangular sputter target composed of three pieces (Zr/TiB{sub 2}/Zr) was used as the source of evaporation of coating components. Two different substrate biases (i.e. floating potential and − 50 V) and N{sub 2} reactive-gas flow rates of 2, 4 and 6 sccm were employed as the main deposition parameter variables. The chemical composition, structure, morphology and mechanical properties were investigated using a variety of analytical techniques such as Glow-Discharge Optical Emission Spectroscopy, cross-sectional Scanning Electron Microscopy (SEM), Glancing Angle X-ray Diffraction (GAXRD) and nanoindentation. With other parameters fixed, coating properties were found to be dependent on the substrate negative bias and nitrogen flow rate. Linear scan profiles and SEM imaging revealed that all coatings were smooth, dense and featureless (in fracture cross section) with no apparent columnar morphology or macro-defects. GAXRD structural analysis revealed that mostly metallic phases were formed for coatings containing no nitrogen, whereas a solid solution (Zr,Ti)N single phase nitride was found in most of the reactively deposited coatings — exhibiting a very small grain size due to nitrogen and boron grain refinement effects. Hardness values from as low as 8.6 GPa up to a maximum of 25.9 GPa are related mainly to solid solution strengthening effects. The measured elastic moduli correlated with the trends in hardness behaviour; values in the range of 120–200 GPa were observed depending on the selected deposition parameters. Also, high H/E values (> 0.1) were achieved with several of the coatings.

Mitigation of greenhouse gas emissions in the French winter oilseed rape in order to produce sustainable biodiesel

Directory of Open Access Journals (Sweden)

Flénet Francis

2012-05-01

Full Text Available The objectives of the study were (1 to evaluate the possibility for the French winter oilseed rape to achieve the 50% greenhouse gas (GHG saving criteria of the European Directive on the promotion of renewable energy (2009/28/EC, and (2 to investigate mitigation options. The agricultural GHG emissions were calculated with the actual seed yields and cultural operations of more than 5000 winter oilseed rape fields producing seeds collected by 27 grain storage companies (GSC, while the same values of GHG emissions for transport and biodiesel processing were used for all GSC. The study clearly showed that the 50% GHG saving criteria could not be achieved each year, by each of the grain storage company, without improvements of crop management. The possibility to reduce the GHG emissions by improving the efficiency of mineral N fertilization was demonstrated. Improving seed yields without increasing the amount of N application on the fields would also decrease GHG emissions. On the contrary, the application of organic matter appeared to be largely ineffective because of the way N2O emissions were calculated in the study (tier 1 method of International Panel on Climate Change.

Coagulation of dielectric dust grains due to variable asymmetric charging

International Nuclear Information System (INIS)

Manweiler, Jerry W.; Armstrong, Thomas P.; Cravens, Thomas E.

1998-01-01

Observational evidence of electrical forces acting significantly on small solids is present for both the modern solar system in Saturn's rings and the ancient solar system in chondritic meteorites. It is likely that grain-grain coagulation rates are affected by the distribution of charges on small grains. Plasma particle impacts and photoelectric effects can provide the charges. It appears that some charging is inevitable and that plasma grain interactions need to be evaluated to determine the size of the effect on coagulation rates. We apply the results of our previous charging work to models of the protoplanetary nebula. It is expected that the protoplanetary nebula is weakly ionized except in certain instances and locations such as: solar flares in the interior, ultraviolet radiation at the outer boundary, and during enhanced luminosity of the star. Since the grains we study are non-conducting and show strong dipole moments in flowing plasma, we modify the geometric cross sections to include the effects of flowing plasma on non-conducting grains with plasma mediated shielding. This paper provides results showing how plasma flow affects the processes involved in charging the grains--total charge and charge distribution. We calculate the modifications to the cross sections and subsequent changes in the coagulation rates

PRODUCTION AND RECOIL LOSS OF COSMOGENIC NUCLIDES IN PRESOLAR GRAINS

International Nuclear Information System (INIS)

Trappitsch, Reto; Leya, Ingo

2016-01-01

Presolar grains are small particles that condensed in the vicinity of dying stars. Some of these grains survived the voyage through the interstellar medium (ISM) and were incorporated into meteorite parent bodies at the formation of the Solar System. An important question is when these stellar processes happened, i.e., how long presolar grains were drifting through the ISM. While conventional radiometric dating of such small grains is very difficult, presolar grains are irradiated with galactic cosmic rays (GCRs) in the ISM, which induce the production of cosmogenic nuclides. This opens the possibility to determine cosmic-ray exposure (CRE) ages, i.e., how long presolar grains were irradiated in the ISM. Here, we present a new model for the production and loss of cosmogenic 3 He, 6,7 Li, and 21,22 Ne in presolar SiC grains. The cosmogenic production rates are calculated using a state-of-the-art nuclear cross-section database and a GCR spectrum in the ISM consistent with recent Voyager data. Our findings are that previously measured 3 He and 21 Ne CRE ages agree within the (sometimes large) 2 σ uncertainties and that the CRE ages for most presolar grains are smaller than the predicted survival times. The obtained results are relatively robust since interferences from implanted low-energy GCRs into the presolar SiC grains and/or from cosmogenic production within the meteoroid can be neglected.

Segregation of solute elements at grain boundaries in an ultrafine grained Al-Zn-Mg-Cu alloy

International Nuclear Information System (INIS)

Sha, Gang; Yao, Lan; Liao, Xiaozhou; Ringer, Simon P.; Chao Duan, Zhi; Langdon, Terence G.

2011-01-01

The solute segregation at grain boundaries (GBs) of an ultrafine grained (UFG) Al-Zn-Mg-Cu alloy processed by equal-channel angular pressing (ECAP) at 200 o C was characterised using three-dimensional atom probe. Mg and Cu segregate strongly to the grain boundaries. In contrast, Zn does not always show clear segregation and may even show depletion near the grain boundaries. Trace element Si selectively segregates at some GBs. An increase in the number of ECAP passes leads to a decrease in the grain size but an increase in solute segregation at the boundaries. The significant segregation of alloying elements at the boundaries of ultrafine-grained alloys implies that less solutes will be available in the matrix for precipitation with a decrease in the average grain size. -- Research Highlights: → Atom probe tomography has been employed successfully to reveal unique segregation of solutes at ultrafine grained material. → Mg and Cu elements segregated strongly at the grain boundary of an ultrafine grained Al-Zn-Mg-Cu alloy processed by 4-pass and 8-pass ECAP at 200 o C. Zn frequently depleted at GBs with a Zn depletion region of 7-15 nm in width on one or both sides of the GBs. Only a small fraction (3/13) of GBs were observed with a low level of Zn segregation where the combined Mg and Cu excess is over 3.1 atom/nm 2 . Si appeared selectively segregated at some of the GBs. → The increase in number of ECAP passes from 4 to 8 correlated with the increase in mean level segregation of Mg and Cu for both solute excess and peak concentration. → The change of plane normal of a grain boundary within 30 o only leads to a slight change in the solute segregation level.

Macro-Elements and Trace Elements in Cereal Grains Cultivated in Latvia

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Jākobsone Ida

2015-09-01

Full Text Available Cereal-based foods have great importance in the compensation of micro- and trace element deficiency, because 50% of the foods produced worldwide are made up of cereal grains. The aim of the research was to determine the concentration of macro-elements and trace elements in different cereals cultivated in Latvia. Various cereals were used in the research: rye (n = 45, barley (n = 54, spring wheat (n = 27, winter wheat (n = 53, triticale (n = 45 and oats (n = 42. Thirteen macro- and trace elements (Cd, Pb, Ni, Cr, Al, Cu, K, Na, Mn, Fe, Zn, Mg, Ca were determined in cereal grain samples (n = 266. Macro-elements and trace elements varied significantly (p < 0.01 or p < 0.001. The highest concentrations of macro- and trace elements were found in oats and the lowest in rye. The obtained data will expand the opportunity for food and nutrition scientists to evaluate content of the examined elements in grain products, and dietary consumption (bioavailability of the examined macro-elements and trace elements.

Applying stochastic small-scale damage functions to German winter storms

Science.gov (United States)

Prahl, B. F.; Rybski, D.; Kropp, J. P.; Burghoff, O.; Held, H.

2012-03-01

Analyzing insurance-loss data we derive stochastic storm-damage functions for residential buildings. On district level we fit power-law relations between daily loss and maximum wind speed, typically spanning more than 4 orders of magnitude. The estimated exponents for 439 German districts roughly range from 8 to 12. In addition, we find correlations among the parameters and socio-demographic data, which we employ in a simplified parametrization of the damage function with just 3 independent parameters for each district. A Monte Carlo method is used to generate loss estimates and confidence bounds of daily and annual storm damages in Germany. Our approach reproduces the annual progression of winter storm losses and enables to estimate daily losses over a wide range of magnitudes.

High yielding small grain mutant of rice variety Pankaj

Energy Technology Data Exchange (ETDEWEB)

NONE

1987-07-01

Full text: By treatment with EMS a mutant has been produced from the variety Pankaj which has better tillering, longer panicle and more grains per panicle. In multilocation trials at Burdwan, Suri and Rampurhat in West Bengal it yielded significantly more than Pankaj and Mahsuri at all locations, with a mean 5.2t. The mutant named BU 79 would be a suitable substitute for Pankaj and similar long-duration rices. (author)

Radon emanation rate as a function of monazite grain size

International Nuclear Information System (INIS)

Yogesan, S.; Stanley, J.D.; Rosli Mahat; Yusof Md Amin

1995-01-01

In this study, a sample of monazite from local mining area was divided to 7 parts according to size (μm) and each sample was analysed using silicon surface barrier detector and multichannel analyser. From this study it has found that small grain monazite produced more radon that big grain monazite and radium is distributed on or near the surface of the monazite grain

Sistemas de coberturas de solo no inverno e seus efeitos sobre o rendimento de grãos do milho em sucessão Soil covering systems in the winter and its effects on maize grain yield grown in succession

Directory of Open Access Journals (Sweden)

Adriano Alves da Silva

2007-08-01

milho também aumenta quando em sucessão à ervilhaca.The black oats use (Avena strigosa as species of soil covering in the winter, cause immobilization of the nitrogen (N, that reduces the plant development and grain yield of maize cultivated in succession. Thus, the black oat intercropped systems with leguminous as common vetch (Vicia sativa and brassicas as oilseed radish (Raphanus sativus is aimed at increasing nitrogen (N disponibility in the system and the permanence timing of its residues in the soil. Two experiments were carried out in the growth seasons of 2001/2002 and 2002/2003, in Rio Grande do Sul, Brazil. The first one was aimed at evaluating the effect of three winter species of soil covering, grown as a single culture and as intercropped crops on maize grain yield, with and without nitrogen side-dressed. The second one was aimed at determining the most adequate seed ratio of oilseed radish and black oat in intercropped systems, as soil covering crops in the winter preceding maize, under different nitrogen levels side-dressed. In Experiment I, treatments were composed by N application of 180kg ha-1, a control without N side-dressed and seven winter soil covering systems. In the Experiment II, treatments consisted of two levels of N side-dressing application in maize, a control without N side-dressed, and of three seed ratio of oilseed radish and black oat, as single and as intercropped crops and a control without crop in the winter. In all intercropped systems, independently of seed ratio used, the oilseed radish was mostly responsible for the yield of dry mass of the systems. The intercropped systems of common vetch or oilseed radish with black oat minimize the negative effect of oat on maize grain yield cultivated in succession in systems with low N availability and, even with high N supply, maize grain yield also increases when grown after common vetch.

The Impact of Phosphorus Supply on Selenium Uptake During Hydroponics Experiment of Winter Wheat (Triticum aestivum) in China.

Science.gov (United States)

Liu, Hongen; Shi, Zhiwei; Li, Jinfeng; Zhao, Peng; Qin, Shiyu; Nie, Zhaojun

2018-01-01

Selenium (Se) is a necessary trace element for humans and animals, and Se fertilization is an efficient way to increase Se concentration in the edible parts of crops, thus enhance the beneficiary effects of Se in human and animal health. Due to the similarity of physical and chemical properties between phosphate () and selenite (), phosphorus (P) supply often significantly impacts the absorption of Se in plants, but little is known about how P supply influences the subcellular distribution and chemical forms of Se. In this study, the effects of P supply on subcellular distribution and chemical forms of Se in winter wheat were investigated in a hydroponic trial with medium Se level (0.1 mg Se L -1 ). P was applied with three concentrations (0.31, 3.1, and 31 mg P L -1 ) in the experiment. The results showed that increasing P supply significantly decreased the concentration and accumulation of Se in the roots, stems, and leaves of winter wheat. An increase in P supply significantly inhibited Se accumulation in the root cell wall, but enhanced Se distribution in the organelles and soluble fraction of root cells. These findings suggest that increased P supply inhibited the root-to-shoot transport of Se. An increase in P supply enhanced Se accumulation in the cell wall of plant stems (both apical and axillary stem) and cell organelles of plants leaves, but inhibited Se distribution in the soluble fraction of stems and leaves. This suggests that P supply enhances Se transportation across the cell membrane in shoots of winter wheat. In addition, increased P supply also altered the chemical forms of Se in tissues of winter wheat. These findings will help in understanding of the regulation grain Se accumulation and provide a practical way to enhance Se intake for humans inform Se-enriched grains.

Discrete stochastic charging of aggregate grains

Science.gov (United States)

Matthews, Lorin S.; Shotorban, Babak; Hyde, Truell W.

2018-05-01

Dust particles immersed in a plasma environment become charged through the collection of electrons and ions at random times, causing the dust charge to fluctuate about an equilibrium value. Small grains (with radii less than 1 μm) or grains in a tenuous plasma environment are sensitive to single additions of electrons or ions. Here we present a numerical model that allows examination of discrete stochastic charge fluctuations on the surface of aggregate grains and determines the effect of these fluctuations on the dynamics of grain aggregation. We show that the mean and standard deviation of charge on aggregate grains follow the same trends as those predicted for spheres having an equivalent radius, though aggregates exhibit larger variations from the predicted values. In some plasma environments, these charge fluctuations occur on timescales which are relevant for dynamics of aggregate growth. Coupled dynamics and charging models show that charge fluctuations tend to produce aggregates which are much more linear or filamentary than aggregates formed in an environment where the charge is stationary.

Observed Decrease of North American Winter Temperature Variability

Science.gov (United States)

Rhines, A. N.; Tingley, M.; McKinnon, K. A.; Huybers, P. J.

2015-12-01

There is considerable interest in determining whether temperature variability has changed in recent decades. Model ensembles project that extratropical land temperature variance will detectably decrease by 2070. We use quantile regression of station observations to show that decreasing variability is already robustly detectable for North American winter during 1979--2014. Pointwise trends from GHCND stations are mapped into a continuous spatial field using thin-plate spline regression, resolving small-scales while providing uncertainties accounting for spatial covariance and varying station density. We find that variability of daily temperatures, as measured by the difference between the 95th and 5th percentiles, has decreased markedly in winter for both daily minima and maxima. Composites indicate that the reduced spread of winter temperatures primarily results from Arctic amplification decreasing the meridional temperature gradient. Greater observed warming in the 5th relative to the 95th percentile stems from asymmetric effects of advection during cold versus warm days; cold air advection is generally from northerly regions that have experienced greater warming than western or southwestern regions that are generally sourced during warm days.

Fracture toughness of WWER Uranium dioxide fuel pellets with various grain size

International Nuclear Information System (INIS)

Sivov, R.; Novikov, V.; Mikheev, E.; Fedotov, A.

2015-01-01

Uranium dioxide fuel pellets with grain sizes 13, 26, and 33 μm for WWER were investigated in the present work in order to determine crack formation and the fracture toughness.The investigation of crack formation in uranium oxide fuel pellets of the WWER-types showed that Young’s modulus and the microhardness of polycrystalline samples increase with increasing grain size, while the fracture toughness decreases. Characteristically, radial Palmqvist cracks form on the surface of uranium dioxide pellets for loads up to 1 kg. Transgranular propagation of cracks over distances several-fold larger than the length of the imprint diagonal is observed in pellets with large grains and small intragrain pores. Intergranular propagation of cracks along grain boundaries with branching occurs in pellets with small grains and low pore concentration on the grain boundaries. Blunting on large pores and at breaks in direction does not permit the cracks to reach a significant length

Accommodation of Plastic Deformation by Ultrasound-Induced Grain Rotation

NARCIS (Netherlands)

Dutta, R.K.; Petrov, R.H.; Hermans, M.J.M.; Richardson, I.M.

2015-01-01

Electron backscatter diffraction was used to investigate the softening effect in low-carbon steel [Fe-0.051C-0.002Si-0.224Mn-0.045Al (wt pct)] during tensile deformation with in situ ultrasonic treatment. A bimodal grain size distribution is observed with relatively small equiaxed grains with an

New winter hardy winter bread wheat cultivar (Triticum aestivum L. Voloshkova

Directory of Open Access Journals (Sweden)

Л. М. Голик

2007-12-01

Full Text Available Creation of Initial raw for breeding of winter wheat by change of the development type under low temperatures influence was described. Seeds of spring wheat were vernalized in aluminum weighting bottle. By using low temperatures at sawing of M2-6 at the begin ind of optimal terms of sawing of winter wheat, new winter-hardy variety of Voloshkova was bred.

Application of carbon extraction replicas in grain-size measurements of high-strength steels using TEM

International Nuclear Information System (INIS)

Poorhaydari, Kioumars; Ivey, Douglas G.

2007-01-01

In this paper, the application of carbon extraction replicas in grain-size measurements is introduced and discussed. Modern high-strength microalloyed steels, used as structural or pipeline materials, have very small grains with substructures. Replicas used in transmission electron microscopes can resolve the grain boundaries and can be used for systematic measurement of grain size in cases where the small size of the grains pushes the resolution of conventional optical microscopes. The grain-size variations obtained from replicas are compared with those obtained from optical and scanning electron microscopy. An emphasis is placed on the importance of using the correct technique for imaging and the optimal magnification. Grain-size measurements are used for estimation of grain-boundary strengthening contribution to yield strength. The variation in grain size is also correlated with hardness in the base metal of several microalloyed steels, as well as the fine-grained heat-affected zone of a weld structure with several heat inputs

33 CFR 100.109 - Winter Harbor Lobster Boat Race, Winter Harbor, ME.

Science.gov (United States)

2010-07-01

... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false Winter Harbor Lobster Boat Race, Winter Harbor, ME. 100.109 Section 100.109 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY REGATTAS AND MARINE PARADES SAFETY OF LIFE ON NAVIGABLE WATERS § 100.109 Winter Harbor...

Long-term effects of manure and inorganic fertilizers on yield and soil fertility for a winter wheat-maize system in Jiangsu, China

NARCIS (Netherlands)

Dong, J.; Hengsdijk, H.; Dai, T.; Boer, de W.; Qi, J.; Cao, W.

2006-01-01

Winter wheat-maize rotations are dominant cropping systems on the North China Plain, where recently the use of organic manure with grain crops has almost disappeared. This could reduce soil fertility and crop productivity in the long run. A 20-year field experiment was conducted to 1) assess the

Comparison of snowpack and winter wet-deposition chemistry in the Rocky Mountains, USA: implications for winter dry deposition

Science.gov (United States)

Clow, David W.; Ingersoll, George P.; Mast, M. Alisa; Turk, John T.; Campbell, Donald H.

Depth-integrated snowpack chemistry was measured just prior to maximum snowpack depth during the winters of 1992-1999 at 12 sites co-located with National Atmospheric Deposition Program/National Trend Network (NADP/NTN) sites in the central and southern Rocky Mountains, USA. Winter volume-weighted mean wet-deposition concentrations were calculated for the NADP/NTN sites, and the data were compared to snowpack concentrations using the paired t-test and the Wilcoxon signed-rank test. No statistically significant differences were indicated in concentrations of SO 42- or NO 3- ( p>0.1). Small, but statistically significant differences ( p⩽0.03) were indicated for all other solutes analyzed. Differences were largest for Ca 2+ concentrations, which on average were 2.3 μeq l -1 (43%) higher in the snowpack than in winter NADP/NTN samples. Eolian carbonate dust appeared to influence snowpack chemistry through both wet and dry deposition, and the effect increased from north to south. Dry deposition of eolian carbonates was estimated to have neutralized an average of 6.9 μeq l -1 and a maximum of 12 μeq l -1 of snowpack acidity at the southernmost sites. The good agreement between snowpack and winter NADP/NTN SO 42- and NO 3- concentrations indicates that for those solutes the two data sets can be combined to increase data density in high-elevation areas, where few NADP/NTN sites exist. This combination of data sets will allow for better estimates of atmospheric deposition of SO 42- and NO 3- across the Rocky Mountain region.

PRESENCE OF CITRININ IN GRAINS AND ITS POSSIBLE HEALTH EFFECTS.

Science.gov (United States)

Čulig, Borna; Bevardi, Martina; Bošnir, Jasna; Serdar, Sonja; Lasić, Dario; Racz, Aleksandar; Galić, Antonija; Kuharić, Željka

2017-01-01

Citrinin is a mycotoxin produced by several species of the genera Aspergillus , Penicillium and Monascus and it occurs mainly in stored grain. Citrinin is generally formed after harvest and occurs mainly in stored grains, it also occurs in other plant products. Often, the co-occurrence with other mycotoxins is observed, especially ochratoxin A, which is usually associated with endemic nephropathy. At the European Union level, systematic monitoring of Citrinin in grains began with the aim of determining its highest permissible amount in food. Thus, far the systematic monitoring of the above mentioned mycotoxin in Croatia is yet to begin. The main goal of this study was to determine the presence of Citrinin in grains sampled in the area of Međimurje, Osijek-Baranja, Vukovar-Srijem and Brod-Posavina County. For the purpose of identification and quantification of citrinin, high performance liquid chromatograph (HPLC) with fluorescence was used (Calibration curve k > 0.999; Intra assay CV = 2.1%; Inter assay CV = 4.3%; LOQ possibly indicating a significant intake of citrinin in humans. It must be stated that grains and grain-based products are the basis of everyday diet of all age groups, especially small children, where higher intake of citrinin can occur. Consequently, we emphasize the need for systematic analysis of larger amount of samples, from both large grains and small grains, especially in the area of Brod-Posavina County, in order to obtain more realistic notion of citrinin contamination of grains and to asses the health risk in humans.

What do we know about winter active ground beetles (Coleoptera, Carabidae) in Central and Northern Europe?

Science.gov (United States)

Jaskuła, Radomir; Soszyńska-Maj, Agnieszka

2011-01-01

This paper summarizes the current knowledge on winter active Carabidae in Central and Northern Europe. In total 73 winter active species are listed, based on literature and own observations. Ground beetles are among the three most numerous Coleoptera families active during the autumn to spring period. The winter community of Carabidae is composed both of larvae (mainly autumn breeding species) and adults, as well as of epigeic species and those inhabiting tree trunks. Supranivean fauna is characterized by lower species diversity than the subnivean fauna. The activity of ground beetles decreases in late autumn, is lowest during mid-winter and increases in early spring. Carabidae are noted as an important food source in the diet of insectivorous mammals. They are also predators, hunting small winter active invertebrates.

Characteristics of Urban Natural Areas Influencing Winter Bird Use in Southern Ontario, Canada

Science.gov (United States)

Smith, Paul G. R.

2007-03-01

Characteristics of urban natural areas and surrounding landscapes were identified that best explain winter bird use for 28 urban natural areas in southern Ontario, Canada. The research confirms for winter birds the importance of area (size) and natural vegetation, rather than managed, horticultural parkland, within urban natural areas as well as percent urban land use and natural habitat in surrounding landscapes. Alien bird density and percent ground feeding species increased with percent surrounding urban land use. Higher percent forest cover was associated with higher percentages of forest, bark feeding, small (species. Natural area size (ha) was related to higher species richness, lower evenness and higher percentages of insectivorous, forest interior, area-sensitive, upper canopy, bark feeding, and non-resident species. Higher number of habitat types within natural areas and percent natural habitat in surrounding landscapes were also associated with higher species richness. Common, resident bird species dominated small areas (20 ha start to support some area-sensitive species. Areas similar to rural forests had >25% insectivores, >25% forest interior species, >25% small species, and species. Indicator species separated urban natural areas from rural habitats and ordination placed urban natural areas along a gradient between urban development and undisturbed, rural forests. More attention is needed on issues of winter bird conservation in urban landscapes.

Sowing terms of winter bread wheat variety-innovations (Triticum aestivum L. in the conditions of change of climate

Directory of Open Access Journals (Sweden)

О. Л. Дергачов

2010-10-01

Full Text Available Results of studying of influence of sowing terms on productivity and indices of quality of grain of winter bread wheat variety-innovations of V.M. Remeslo Myronivka Institute of Wheat of NAAS of Ukraine in the conditions of Right-bank Forest-steppe are shown. Negative correlation of productivity of varieties on average temperature of air during the sowing period is shown.

Combined effects of elevated temperature and CO2 enhance threat from low temperature hazard to winter wheat growth in North China.

Science.gov (United States)

Tan, Kaiyan; Zhou, Guangsheng; Lv, Xiaomin; Guo, Jianping; Ren, Sanxue

2018-03-12

We examined the growth and yield of winter wheat (Triticum aestivum) in response to the predicted elevated CO 2 concentration and temperature to determine the mechanism of the combined impacts in North China Plain. An elevated treatment (CO 2 : 600 μmol mol -1 , temperature: +2.5~3.0 °C, ECTI) and a control treatment (ambient CO 2 and temperature, CK) were conducted in open-top chambers from October 2013 to June 2016. Post-winter growth stages of winter wheat largely advanced and shifted to a cooler period of nature season under combined impact of elevated CO 2 and temperature during the entire growing season. The mean temperature and accumulated photosynthetic active radiations (PAR) over the post-winter growing period in ECTI decreased by 0.8-1.5 °C and 10-13%, respectively compared with that in CK, negatively impacted winter wheat growth. As a result, winter wheat in ECTI suffered from low temperature hazards during critical period of floret development and anthesis and grain number per ear was reduced by 10-31% in the three years. Although 1000-kernel weight in ECTI increased by 8-9% mainly due to elevated CO 2 , increasing CO 2 concentration from 400 to 600 μmol mol -1 throughout the growth stage was not able to offset the adverse effect of warming on winter wheat growth and yield.

Cohesion of Mm- to Cm-Sized Asteroid Simulant Grains: An Experimental Study

Science.gov (United States)

Brisset, Julie; Colwell, Joshua E.; Dove, Adrienne; Jarmak, Stephanie; Anderson, Seamus

2017-10-01

The regolith covering the surfaces of asteroids and planetary satellites is very different from terrestrial soil particles and subject to environmental conditions very different from what is found on Earth. The loose, unconsolidated granular material has angular-shaped grains and a broad size distribution. On small and airless bodies (Earth surface gravity, the cohesion behavior of the regolith grains will dictate the asteroid’s surface morphology and its response to impact or spacecraft contact.Previous laboratory experiments on low-velocity impacts into regolith simulant with grain sizes landing missions to small bodies such as asteroids or Martian moons.

Fluctuations of the charge on a dust grain in a plasma

International Nuclear Information System (INIS)

Cui, C.; Goree, J.

1994-01-01

A dust grain in a plasma acquires an electric charge by collecting electron and ion currents. These currents consist of discrete charges, causing the charge to fluctuate around an equilibrium value (Q). Electrons and ions are collected at random intervals and in a random sequence, with probabilities that depend on the grain's potential. The authors developed a model for these probabilities and implemented it in a numerical simulation of the collection of individual ions and electrons, yielding a time series Q(t) for the grain's charge. Electron emission from the grain is not included, although it could be added easily to the method. They obtained the power spectrum and the rms fluctuation level, as well as the distribution function of the charge. Most of the power in the spectrum lies at frequencies much lower than 1/τ, the inverse charging time. The rms fractional fluctuation level varies as 0.5 |left-angle N right-angle | -1/2 , where left-angle N right-angle = left-angle Q right-angle/e is the average number of electron charges on the grain. This inverse square-root scaling means that fluctuations are most important for small grains. They also show that very small grains can experience fluctuations to neutral and positive polarities, even in the absence of electron emission

Grain boundaries of nanocrystalline materials - their widths, compositions, and internal structures

International Nuclear Information System (INIS)

Fultz, B.; Frase, H.N.

2000-01-01

Nanocrystalline materials contain many atoms at and near grain boundaries. Sufficient numbers of Moessbauer probe atoms can be situated in grain boundary environments to make a clear contribution to the measured Moessbauer spectrum. Three types of measurements on nanocrystalline materials are reported here, all using Moessbauer spectrometry in conjunction with X-ray diffractometry, transmission electron microscopy, or small angle neutron scattering. By measuring the fraction of atoms contributing to the grain boundary component in a Moessbauer spectrum, and by knowing the grain size of the material, it is possible to deduce the average width of grain boundaries in metallic alloys. It is found that these widths are approximately 0.5 nm for fcc alloys and slightly larger than 1.0 nm for bcc alloys.Chemical segregation to grain boundaries can be measured by Moessbauer spectrometry, especially in conjunction with small angle neutron scattering. Such measurements on Fe-Cu and Fe 3 Si-Nb were used to study how nanocrystalline materials could be stabilized against grain growth by the segregation of Cu and Nb to grain boundaries. The segregation of Cu to grain boundaries did not stabilize the Fe-Cu alloys against grain growth, since the grain boundaries were found to widen and accept more Cu atoms during annealing. The Nb additions to Fe 3 Si did suppress grain growth, perhaps because of the low mobility of Nb atoms, but also perhaps because Nb atoms altered the chemical ordering in the alloy.The internal structure of grain boundaries in nanocrystalline materials prepared by high-energy ball milling is found to be unstable against internal relaxations at low temperatures. The Moessbauer spectra of the nanocrystalline samples showed changes in the hyperfine fields attributable to movements of grain boundary atoms. In conjunction with SANS measurements, the changes in grain boundary structure induced by cryogenic exposure and annealing at low temperature were found to be

Fatigue in tension perpendicular to the grain

DEFF Research Database (Denmark)

Clorius, Christian Odin; Pedersen, Martin Bo Uhre; Hoffmeyer, Preben

1999-01-01

Traditinally fatigue resistance is quantified as number of cycles to failure at a given stress level. A previous study by the authors showed that fatigue in compression parallel to the grain is governed partly by duration of load and partly by an effect of loading, i.e. a combination of a creep...... mechanism and a mechanism connected to damage introduce in the loading sequences. The purpose of the present study is to disentangle the effect of duration of load from the effect of load oscillation in fatigue in tension perpendicular to the grain. Fatigue experiments are made on small specimens...... and on dowel type joints with slotted in steel plates. In series of ten, the small specimens are taken to fatigue failure in uniform tension at square wave shaped load cycles at 0.01 Hz and 0.1 Hz. In order to test the predictive validity of the result from the small tension specimens, fatigue experiments...

Fatigue In Tension Perpendicular to the Grain

DEFF Research Database (Denmark)

Clorius, Christian Odin; Pedersen, Martin Uhre; Hoffmeyer, Preben

2004-01-01

Traditionally fatigue resistance is quantified as number of cycles to failure at a given stress level. A previous study by the authors showed that fatigue in compression parallel to the grain is governed partly by duration of load and partly by an effect of loading, i.e. a combination of a creep...... mechanism and a mechanism connected to damage introduced in the loading sequences. The purpose of the present study is to disentangle the effect of duration of load from the effect of load oscillation in fatigue in tension perpendicular to the grain. Fatigue experiments are made on small specimens...... and on dowel type joints with slotted in steel plates. In series of ten, the small specimens are taken to fatigue failure in uniform tension at square wave shaped load cycles at 0.01 Hz and 0.1 Hz. In arder to test the predictive validity of the result from the small tension specimens, fatigue experiments...

Soil physical attributes in forms of sowing the annual winter pasture and intervals between grazing

Directory of Open Access Journals (Sweden)

Milton da Veiga

Full Text Available The sowing of winter pastures in areas used for summer grain production and their management under direct cattle grazing can cause changes in soil physical attributes, whose intensity depends on the degree of soil mobilization, grazing interval, stocking rate and weather. To study these aspects it was conducted over four years an experiment in a randomized block with split plots design and four replications. In the main plots were applied two forms of sowing the annual winter pasture (direct seeding and seeding + harrowing and, in the subplots, four intervals between grazing (7, 14 and 28 days and ungrazed. Undisturbed soil cores were sampled at the end of each grazing cycle, in the 0-0.05 m layer to determine the saturated hydraulic conductivity and aggregate stability and in the layers of 0-0.05, 0.05-0.10, 0.10-0.15 and 0.15-0.20 m depth to determine bulk density and classes of soil pores. The direct seeding of annual winter pasture increases hydraulic conductivity and reduces soil bulk density in relation to seeding + harrowing while dairy cows trampling increases soil density and reduces macroporosity in the most superficial soil layer. The variation in climatic conditions among grazing cycles affects the soil physical attributes more markedly than forms of sowing and intervals between grazing of the annual winter pasture.

Life Cycle Assessment on Carbon Footprint of Winter Wheat-Summer Maize Cropping System Based on Survey Data of Gaomi in Shandong Province, China

Directory of Open Access Journals (Sweden)

ZHU Yong-chang

2017-08-01

Full Text Available Grain production can generate huge amount of greenhouse gases through raw material production and energy comsumption, nitrogen fertilizer amendment and farming machinery operation. Based questionnaire survey of raw material inputs and management of wheat-maize cropping system in Gaomi, Shandong Province, carbon footprint of grain production was calculated using life cycle assessment methodology. Carbon footprint per unit area of wheat, maize, and winter wheat-summer maize cropping system were 5 183.33, 3 778.09 kg CO2-eq·hm-2 and 8 961.42 kg CO2-eq·hm-2, carbon footprint per unit grain yield were 0.69, 0.40 kg CO2-eq·kg-1 and 0.53 kg CO2-eq·kg-1, carbon footprint per unit net present value were 1.82, 0.40 kg CO2-eq·yuan-1 and 0.44 kg CO2-eq·yuan-1, respectively. Greenhouse gas(GHG emission of winter wheat-summer maize cropping system mainly came from nitrogen fertilizer production(48.30% and nitrogen fertilizer application(12.04%, irrigation electricity consumption(12.94% and machinery oil consumption(11.20%. Optimizing the application of fertilizer, reducing the amount of nitrogen fertilizer and saving water irrigation were important ways to realize the clean production.

An overview of winter squash (Cucurbita maxima Duch. and pumpkin (Cucurbita moschata Duch. growing in Turkey

Directory of Open Access Journals (Sweden)

Ahmet Balkaya

2015-06-01

Full Text Available Cucurbita L. species of the pumpkin and winter squash are grown all over the world. Winter squash and pumpkin are two of the most important Cucurbit vegetable crops in Turkey. Turkey is one of the important diversity areas, for the cultivated cucurbits because of their adaptation to diverse ecological conditions as a result of both natural selection and also the selection by farmers. Farmers have maintained the local population of winter squash and pumpkin, which are mainly sold in local markets. Only one improved cultivar of the winter squash is currently grown commercially in Turkey. It is a traditional vegetable often grown in small gardens. In this contribution, the last status of winter squash and pumpkin production in Turkey, the growing techniques and problems of these winter squash and pumpkin species, their genetic collection and characterization, and the utilization of the presented species in Turkey are examined.

Limitation of multi-elemental fingerprinting of wheat grains: Effect of cultivar, sowing date, and nutrient management

DEFF Research Database (Denmark)

Suarez-Tapia, Alfonso; Kucheryavskiy, Sergey V.; Christensen, Bent Tolstrup

2017-01-01

Multi-element fingerprinting demonstrates some potential for tracing the origin of agricultural products but not for discriminating among crop cultivars and nutrient management (source, rate). With principal component analysis (PCA) and univariate statistics, we examined 19 elements in grains from...... two winter wheat cultivars (Hereford, Mariboss) grown with different rates of animal manure (AM) or mineral fertilisers (NPK) in a long-term field experiment and two sowing dates (early, timely). Nitrogen, Cd and Mn related to NPK, and Mo and Na to AM. Barium, Fe, and P reflected nutrient rate......; these elements increased with nutrient rate regardless of source. Unmanured grains were enriched in Cu. Mariboss was characterized by higher concentrations of Sr, Ba and Sc compared to Hereford with Sr in grain as the main separator. Univariate statistics showed higher concentrations of N, P, Mg, Ba, Cu, Mo...

Comet Grains: Their IR Emission and Their Relation to ISM Grains

Science.gov (United States)

Wooden, Diane H.; DeVincenzi, Donald (Technical Monitor)

2002-01-01

Comets and the chodritic, porous interplanetary dust particles (CP IDPs) that they shed in their comae are reservoirs of primitive solar nebula materials. The high porosity and fragility of cometary grains and CP IDPs, and anomalously high deuterium contents of highly fragile, pyroxene-rich Cluster IDPs imply these aggregate particles contain significant abundances of grains from the interstellar medium (ISM). IR spectra of comets (3 - 40 micron) reveal the presence of a warm (nearIR) featureless emission modeled by amorphous carbon grains. Broad and narrow resonances near 10 and 20 microns are modeled by warm chondritic (50% Fe and 50% Mg) amorphous silicates and cooler Mg-rich crystalline silicate minerals, respectively. Cometary amorphous silicates resonances are well matched by IR spectra of CP IDPs dominated by GEMS (0.1 micron silicate spherules) that are thought to be the interstellar Fe-bearing amorphous silicates produced in AGB stars. Acid-etched ultramicrotomed CP IDP samples, however, show that both the carbon phase (amorphous and aliphatic) and the Mg-rich amorphous silicate phase in GEMS are not optically absorbing. Rather, it is Fe and FeS nanoparticles embedded in the GEMS that makes the CP IDPs dark. Therefore, CP IDPs suggest significant processing has occurred in the ISM. ISM processing probably includes in He' ion bombardment in supernovae shocks. Laboratory experiments show He+ ion bombardment amorphizes crystalline silicates, increases porosity, and reduces Fe into nanoparticles. Cometary crystalline silicate resonances are well matched by IR spectra of laboratory submicron Mg-rich olivine crystals and pyroxene crystals. Discovery of a Mg-pure olivine crystal in a Cluster IDP with isotopically anomalous oxygen indicates that a small fraction of crystalline silicates may have survived their journey from AGB stars through the ISM to the early solar nebula. The ISM does not have enough crystalline silicates (ISM Mg-rich crystals leads to the

Dust Spectroscopy and the Nature of Grains

Science.gov (United States)

Tielens, A. G. G. M.

2006-01-01

Ground-based, air-borne and space-based, infrared spectra of a wide variety of objects have revealed prominent absorption and emission features due to large molecules and small dust grains. Analysis of this data reveals a highly diverse interstellar and circumstellar grain inventory, including both amorphous materials and highly crystalline compounds (silicates and carbon). This diversity points towards a wide range of physical and chemical birthsites as well as a complex processing of these grains in the interstellar medium. In this talk, I will review the dust inventory contrasting and comparing both the interstellar and circumstellar reservoirs. The focus will be on the processes that play a role in the lifecycle of dust in the interstellar medium.

What do we know about winter active ground beetles (Coleoptera, Carabidae in Central and Northern Europe?

Directory of Open Access Journals (Sweden)

Radomir Jaskula

2011-05-01

Full Text Available This paper summarizes the current knowledge on winter active Carabidae in Central and Northern Europe. In total 73 winter active species are listed, based on literature and own observations. Ground beetles are among the three most numerous Coleoptera families active during the autumn to spring period. The winter community of Carabidae is composed both of larvae (mainly autumn breeding species and adults, as well as of epigeic species and those inhabiting tree trunks. Supranivean fauna is characterized by lower species diversity than the subnivean fauna. The activity of ground beetles decreases in late autumn, is lowest during mid-winter and increases in early spring. Carabidae are noted as an important food source in the diet of insectivorous mammals. They are also predators, hunting small winter active invertebrates.

Process of Equiaxed Grains of RE-Al Alloy under Slope Vibration

International Nuclear Information System (INIS)

Xie Shikun; Yi Rongxi; Pan Xiaoliang; Zheng Xiaoqiu; Guo Xiuyan

2010-01-01

A new technique using slope vibration casting process during heating and isothermal holding period to prepare Al-7Si-2RE alloy has been studied. The small, near-spherical and non-dendritic microstructure with the semi-solid processing requirements has been obtained. Experiments show that the cooling method, pouring process and the convection of melt caused by slope vibration had significant effects on the formation of near-spherical primary gains. The water-cooled copper mold casting with slope vibration at the temperature near liquidus can obtain Al-7Si-2RE alloy with small homogeneous equiaxed grains, the average grain diameter is 48.3 μm, and the average grain roundness is 1.92.

BRILLIANT PEBBLES: A METHOD FOR DETECTION OF VERY LARGE INTERSTELLAR GRAINS

International Nuclear Information System (INIS)

Socrates, Aristotle; Draine, Bruce T.

2009-01-01

A photon of wavelength λ ∼ 1 μm interacting with a dust grain of radius a p ∼ 1 mm (a 'pebble') undergoes scattering in the forward direction, largely within a small characteristic diffraction angle θ s ∼ λ/a p ∼ 100''. Though millimeter-size dust grains contribute negligibly to the interstellar medium's visual extinction, the signal they produce in scattered light may be detectable, especially for variable sources. Observations of light scattered at small angles allow for the direct measurement of the large grain population; variable sources can also yield tomographic information of the interstellar medium's mass distribution. The ability to detect brilliant pebble halos requires a careful understanding of the instrument point-spread function.

Contribution of Nitrogen Uptake and Retranslocation during Reproductive Growth to the Nitrogen Efficiency of Winter Oilseed-Rape Cultivars (Brassica napus L. Differing in Leaf Senescence

Directory of Open Access Journals (Sweden)

Fabian Koeslin-Findeklee

2016-01-01

Full Text Available Genotypic variation in N efficiency defined as high grain yield under limited nitrogen (N supply of winter oilseed-rape line-cultivars has been predominantly attributed to N uptake efficiency (NUPT through maintained N uptake during reproductive growth related to functional stay-green. For investigating the role of stay-green, N retranslocation and N uptake during the reproductive phase for grain yield formation, two line cultivars differing in N starvation-induced leaf senescence were grown in a field experiment without mineral N (N0 and with 160 kg N·ha−1 (N160. Through frequent harvests from full flowering until maturity N uptake, N utilization and apparent N remobilization from vegetative plant parts to the pods could be calculated. NUPT proved being more important than N utilization efficiency (NUE for grain yield formation under N-limiting (N0 conditions. For cultivar differences in N efficiency, particularly N uptake during flowering (NUPT and biomass allocation efficiency (HI to the grains, were decisive. Both crop traits were related to delayed senescence of the older leaves. Remobilization of N particularly from stems and leaves was more important for pod N accumulation than N uptake after full flowering. Pod walls (high N concentrations and stems (high biomass mainly contributed to the crop-residue N at maturity. Decreasing the crop-inherent high N budget surplus of winter oilseed-rape requires increasing the low N remobilization efficiency particularly of pod-wall N to the grains. Addressing this conclusion, multi-year and -location field experiments with an extended range of cultivars including hybrids are desirable.

Nanoscale abnormal grain growth in (001) epitaxial ceria

International Nuclear Information System (INIS)

Solovyov, Vyacheslav F.; Develos-Bagarinao, Katherine; Nykypanchuk, Dmytro

2009-01-01

X-ray reciprocal-space mapping and atomic force microscopy (AFM) are used to study kinetics and mechanisms of lateral grain growth in epitaxial (001) ceria (CeO 2 ) deposited by pulsed laser deposition on (001) yttria-stabilized zirconia (YSZ) and (12 lowbar 10) (r-cut) sapphire. Rate and character of the grain growth during postannealing at 1050 deg. C are found to be strongly dependent on the type of the epitaxial substrate. Films deposited on YSZ exhibit signatures of normal grain growth, which stagnated after the lateral grain size reaches 40 nm, consistent with the grain-boundary pinning by the thermal grooving. In contrast, when r-cut sapphire substrate was used, abnormal (secondary) grain growth is observed. A small population of grains grow to well over 100 nm consuming smaller, 100 nm large (001) terminations and rendering the sample single-crystalline quality. The grain growth is accompanied by reduction in lateral rms strain, resulting in a universal grain size--rms strain dependence. Analysis of the AFM and x-ray diffraction data leads to the conclusion that bimodal initial grain population consisting of grains with very different sizes is responsible for initiation of the abnormal growth in (001) CeO 2 films on r-cut sapphire. Due to different surface chemistry, when a YSZ substrate is used, the initial grain distribution is monomodal, therefore only normal growth is active. We demonstrate that a 2.2 deg. miscut of the sapphire substrate eliminates the large-grain population, thus suppressing abnormal grain growth. It is concluded that utilization of abnormal grain growth is a promising way for synthesis of large (001) ceria terminations.

Winter University 2017. Urban rivers as a part of sustainable development

Directory of Open Access Journals (Sweden)

Valeria Nuyanzina

2017-03-01

Full Text Available The article presents proposals worked out by the international teams that took part in the 18th session of International Baikal Winter University of Urban Planning. The session focused on small rivers rehabilitation as a part of sustainable development. Through the case study of the Ushakovka River in Irkutsk, the teams proposed new ideas of riverfront development, which can be also applied to other small rivers.

Pure iron grains are rare in the universe.

Science.gov (United States)

Kimura, Yuki; Tanaka, Kyoko K; Nozawa, Takaya; Takeuchi, Shinsuke; Inatomi, Yuko

2017-01-01

The abundant forms in which the major elements in the universe exist have been determined from numerous astronomical observations and meteoritic analyses. Iron (Fe) is an exception, in that only depletion of gaseous Fe has been detected in the interstellar medium, suggesting that Fe is condensed into a solid, possibly the astronomically invisible metal. To determine the primary form of Fe, we replicated the formation of Fe grains in gaseous ejecta of evolved stars by means of microgravity experiments. We found that the sticking probability for the formation of Fe grains is extremely small; only a few atoms will stick per hundred thousand collisions so that homogeneous nucleation of metallic Fe grains is highly ineffective, even in the Fe-rich ejecta of type Ia supernovae. This implies that most Fe is locked up as grains of Fe compounds or as impurities accreted onto other grains in the interstellar medium.

Winter Weather Emergencies

Science.gov (United States)

Severe winter weather can lead to health and safety challenges. You may have to cope with Cold related health problems, including ... there are no guarantees of safety during winter weather emergencies, you can take actions to protect yourself. ...

Technological quality of common bean grains obtained in different growing seasons

Directory of Open Access Journals (Sweden)

Eliana Francischinelli Perina

2014-03-01

Full Text Available The traits that provide technological quality to common bean grains exhibit genetic and environmental variation and variation in the genotype x environment interaction. In this context, the aim of this study was to assess the effect of different periods of the growing season on the technological quality of common bean grains. The experiment was conducted with 25 bean genotypes (carioca [beige with brown stripes] and black commercial group that are part of the Value for Cultivation and Use (Valor de Cultivo e Uso - VCU trials in three growing seasons, namely, the 2009/2010 rainy season, the 2010/2011 dry season and the 2010/2011 winter season, in a randomized block experimental design with three replications in which the following items were assessed: cooking time (CT, water absorption capacity before cooking (Peanc and after cooking (Peapc, percentage of whole grains (PWG, total soluble solids in the broth (TSSb, volume expansion before cooking (EXPVbc and after cooking (EXPVac, and dry grain density (DD, grain density after maceration (SD and grain density after cooking (CD. Assessments showed that the different growing seasons for obtaining grains for the purpose of analysis of technological quality have an effect on the results and on differentiation among genotypes, indicating genotype x environment interaction. They also showed that the genotypes C2-1-6-1, C4-8-1-1, LP04-03, IAC-Imperador, P5-4-4-1 and Pr11-6-4-1-2 had the best results in relation to cooking time in the mean values of the three growing seasons. The use of early selection based on phenotypic correlations that exist among the technological features is not expressive, due to the variation of magnitude among the different growing seasons.

Multi-model uncertainty analysis in predicting grain N for crop rotations in Europe

Czech Academy of Sciences Publication Activity Database

Yin, X.; Kersebaum, K. C.; Kollas, C.; Baby, S.; Beaudoin, N.; Manevski, K.; Palosuo, T.; Nendel, C.; Wu, L.; Hoffmann, M.; Hoffmann, H. D.; Sharif, B.; Armas-Herrera, C.; Bindi, M.; Charfeddine, M.; Conradt, T.; Constantin, J.; Ewert, F.; Ferrise, R.; Gaiser, T.; de Cortazar-Atauri, I. G.; Giglio, L.; Hlavinka, Petr; Lana, M.; Launay, M.; Louarn, G.; Manderscheid, R.; Mary, B.; Mirschel, W.; Moriondo, M.; Oeztuerk, M.; Pacholski, A.; Ripoche-Wachter, D.; Roetter, R. P.; Ruget, F.; Trnka, Miroslav; Ventrella, D.; Weigel, H-J.; Olesen, J. E.

2017-01-01

Roč. 84, mar (2017), s. 152-165 ISSN 1161-0301 R&D Projects: GA MŠk(CZ) LO1415 Institutional support: RVO:67179843 Keywords : air co2 enrichment * climate-change * catch crops * nitrogen-fertilization * wheat production * winter-wheat * model stics * sugar-beet * wide-range * growth * Continuous simulation * Grain N * Model calibration * Model ensemble * Model inter-comparison * Single year simulation Subject RIV: GC - Agronomy OBOR OECD: Agronomy , plant breeding and plant protection Impact factor: 3.757, year: 2016

Novel Field Data on Phytoextraction: Pre-Cultivation With Salix Reduces Cadmium in Wheat Grains.

Science.gov (United States)

Greger, Maria; Landberg, Tommy

2015-01-01

Cadmium (Cd) is a health hazard, and up to 43% of human Cd intake comes from wheat products, since Cd accumulates in wheat grains. Salix spp. are high-accumulators of Cd and is suggested for Cd phytoextraction from agricultural soils. We demonstrate, in field, that Salix viminalis can remove Cd from agricultural soils and thereby reduce Cd accumulation in grains of wheat subsequently grown in a Salix-treated field. Four years of Salix cultivation reduce Cd concentration in the soil by up to 27% and in grains of the post-cultivated wheat by up to 33%. The higher the plant density of the Salix, the greater the Cd removal from the soil and the lower the Cd concentration in the grains of post-cultivated wheat, the Cd reduction remaining stable several years after Salix cultivation. The effect occurred in both sandy and clayey soil and in winter and spring bread wheat cultivars. Already one year of Salix cultivation significantly decrease Cd in post grown wheat grains. With this field experiment we have demonstrated that phytoextraction can reduce accumulation of a pollutant in post-cultivated wheat and that phytoextraction has no other observed effect on post-cultivated crops than reduced uptake of the removed pollutant.

Disintegration of Dust Aggregates in Interstellar Shocks and the Lifetime of Dust Grains in the ISM

Science.gov (United States)

Dominik, C.; Jones, A. P.; Tielens, A. G. G. M.; Cuzzi, Jeff (Technical Monitor)

1994-01-01

Interstellar grains are destroyed by shock waves moving through the ISM. In fact, the destruction of grains may be so effective that it is difficult to explain the observed abundance of dust in the ISM as a steady state between input of grains from stellar sources and destruction of grains in shocks. This is especially a problem for the larger grains. Therefore, the dust grains must be protected in some way. Jones et al. have already considered coatings and the increased post-shock drag effects for low density grains. In molecular clouds and dense clouds, coagulation of grains is an important process, and the largest interstellar grains may indeed be aggregates of smaller grains rather than homogeneous particles. This may provide a means to protect the larger grains, in that, in moderate velocity grain-grain collisions in a shock the aggregates may disintegrate rather than be vaporized. The released small particles are more resilient to shock destruction (except in fast shocks) and may reform larger grains later, recovering the observed size distribution. We have developed a model for the binding forces in grain aggregates and apply this model to the collisions between an aggregate and fast small grains. We discuss the results in the light of statistical collision probabilities and grain life times.

Winter survival of Scots pine seedlings under different snow conditions.

Science.gov (United States)

Domisch, Timo; Martz, Françoise; Repo, Tapani; Rautio, Pasi

2018-04-01

Future climate scenarios predict increased air temperatures and precipitation, particularly at high latitudes, and especially so during winter. Soil temperatures, however, are more difficult to predict, since they depend strongly on the fate of the insulating snow cover. 'Rain-on-snow' events and warm spells during winter can lead to thaw-freeze cycles, compacted snow and ice encasement, as well as local flooding. These adverse conditions could counteract the otherwise positive effects of climatic changes on forest seedling growth. In order to study the effects of different winter and snow conditions on young Scots pine (Pinus sylvestris L.) seedlings, we conducted a laboratory experiment in which 80 1-year-old Scots pine seedlings were distributed between four winter treatments in dasotrons: ambient snow cover (SNOW), compressed snow and ice encasement (ICE), flooded and frozen soil (FLOOD) and no snow (NO SNOW). During the winter treatment period and a 1.5-month simulated spring/early summer phase, we monitored the needle, stem and root biomass of the seedlings, and determined their starch and soluble sugar concentrations. In addition, we assessed the stress experienced by the seedlings by measuring chlorophyll fluorescence, electric impedance and photosynthesis of the previous-year needles. Compared with the SNOW treatment, carbohydrate concentrations were lower in the FLOOD and NO SNOW treatments where the seedlings had almost died before the end of the experiment, presumably due to frost desiccation of aboveground parts during the winter treatments. The seedlings of the ICE treatment showed dead needles and stems only above the snow and ice cover. The results emphasize the importance of an insulating and protecting snow cover for small forest tree seedlings, and that future winters with changed snow patterns might affect the survival of tree seedlings and thus forest productivity.

The role of martensitic transformation on bimodal grain structure in ultrafine grained AISI 304L stainless steel

International Nuclear Information System (INIS)

Sabooni, S.; Karimzadeh, F.; Enayati, M.H.; Ngan, A.H.W.

2015-01-01

In the present study, metastable AISI 304L austenitic stainless steel samples were subjected to different cold rolling reductions from 70% to 93%, followed by annealing at 700 °C for 300 min to form ultrafine grained (UFG) austenite with different grain structures. Transmission electron microscopy (TEM) and nanoindentation were used to characterize the martensitic transformation, in order to relate it to the bimodal distribution of the austenite grain size after subsequent annealing. The results showed that the martensite morphology changed from lath type in the 60% rolled sample to a mixture of lath and dislocation-cell types in the higher rolling reductions. Calculation of the Gibbs free energy change during the reversion treatment showed that the reversion mechanism is shear controlled at the annealing temperature and so the morphology of the reverted austenite is completely dependent on the morphology of the deformation induced martensite. It was found that the austenite had a bimodal grain size distribution in the 80% rolled and annealed state and this is related to the existence of different types of martensite. Increasing the rolling reduction to 93% followed by annealing caused changing of the grain structure to a monomodal like structure, which was mostly covered with small grains of around 300 nm. The existence of bimodal austenite grain size in the 80% rolled and annealed 304L stainless steel led to the improvement of ductility while maintaining a high tensile strength in comparison with the 93% rolled and annealed sample

Monte Carlo tests of small-world architecture for coarse-grained networks of the United States railroad and highway transportation systems

Science.gov (United States)

Aldrich, Preston R.; El-Zabet, Jermeen; Hassan, Seerat; Briguglio, Joseph; Aliaj, Enela; Radcliffe, Maria; Mirza, Taha; Comar, Timothy; Nadolski, Jeremy; Huebner, Cynthia D.

2015-11-01

Several studies have shown that human transportation networks exhibit small-world structure, meaning they have high local clustering and are easily traversed. However, some have concluded this without statistical evaluations, and others have compared observed structure to globally random rather than planar models. Here, we use Monte Carlo randomizations to test US transportation infrastructure data for small-worldness. Coarse-grained network models were generated from GIS data wherein nodes represent the 3105 contiguous US counties and weighted edges represent the number of highway or railroad links between counties; thus, we focus on linkage topologies and not geodesic distances. We compared railroad and highway transportation networks with a simple planar network based on county edge-sharing, and with networks that were globally randomized and those that were randomized while preserving their planarity. We conclude that terrestrial transportation networks have small-world architecture, as it is classically defined relative to global randomizations. However, this topological structure is sufficiently explained by the planarity of the graphs, and in fact the topological patterns established by the transportation links actually serve to reduce the amount of small-world structure.

Film grain noise modeling in advanced video coding

Science.gov (United States)

Oh, Byung Tae; Kuo, C.-C. Jay; Sun, Shijun; Lei, Shawmin

2007-01-01

A new technique for film grain noise extraction, modeling and synthesis is proposed and applied to the coding of high definition video in this work. The film grain noise is viewed as a part of artistic presentation by people in the movie industry. On one hand, since the film grain noise can boost the natural appearance of pictures in high definition video, it should be preserved in high-fidelity video processing systems. On the other hand, video coding with film grain noise is expensive. It is desirable to extract film grain noise from the input video as a pre-processing step at the encoder and re-synthesize the film grain noise and add it back to the decoded video as a post-processing step at the decoder. Under this framework, the coding gain of the denoised video is higher while the quality of the final reconstructed video can still be well preserved. Following this idea, we present a method to remove film grain noise from image/video without distorting its original content. Besides, we describe a parametric model containing a small set of parameters to represent the extracted film grain noise. The proposed model generates the film grain noise that is close to the real one in terms of power spectral density and cross-channel spectral correlation. Experimental results are shown to demonstrate the efficiency of the proposed scheme.

Polar mesosphere winter echoes during MaCWAVE

Directory of Open Access Journals (Sweden)

S. Kirkwood

2006-07-01

Full Text Available During the MaCWAVE winter campaign in January 2003, layers of enhanced echo power known as PMWE (Polar Mesosphere Winter Echoes were detected by the ESRAD 52 MHz radar on several occasions. The cause of these echoes is unclear and here we use observations by meteorological and sounding rockets and by lidar to test whether neutral turbulence or aerosol layers might be responsible. PMWE were detected within 30 min of meteorological rocket soundings (falling spheres on 5 separate days. The observations from the meteorological rockets show that, in most cases, conditions likely to be associated with neutral atmospheric turbulence are not observed at the heights of the PMWE. Observations by instrumented sounding rockets confirm low levels of turbulence and indicate considerable small-scale structure in charge density profiles. Comparison of falling sphere and lidar data, on the other hand, show that any contribution of aerosol scatter to the lidar signal at PMWE heights is less than the detection threshold of about 10%.

Experimental log hauling through a traditional caribou wintering area

Directory of Open Access Journals (Sweden)

Harold G. Cumming

1998-03-01

Full Text Available A 3-year field experiment (fall 1990-spring 1993 showed that woodland caribou (Rangifer tarandus caribou altered their dispersion when logs were hauled through their traditional wintering area. Unlike observations in control years 1 and 3, radio-collared caribou that had returned to the study area before the road was plowed on January 6 of the experimental year 2, moved away 8-60 km after logging activities began. Seasonal migration to Lake Nipigon islands usually peaked in April, but by February 22 of year 2, 4 of the 6 had returned. The islands provide summer refuge from predation, but not when the lake is frozen. Tracks in snow showed that some caribou remained but changed locations. They used areas near the road preferentially in year 1, early year 2, and year 3, but moved away 2-5 km after the road was plowed in year 2. In a nearby undisturbed control area, no such changes occurred. Caribou and moose partitioned habitat on a small scale; tracks showed gray wolf (Canis lupus remote from caribou but close to moose tracks. No predation on caribou was observed within the wintering area; 2 kills were found outside it. Due to the possibility of displacing caribou from winter refugia to places with higher predation risk, log hauling through important caribou winter habitat should be minimized.

Evaluation of nitrogen uptake patterns in spring and winter wheat in western Oregon

International Nuclear Information System (INIS)

Baloch, D.M.; Malghani, M.A.K.; Khan, M.A.; Kakar, E.

2010-01-01

An understanding of the ground nitrogen (N) uptake pattern for wheat (Triticum aestivum L.) is essential to facilitate nitrogen management. The purpose of this study was to determine the nitrogen uptake pattern of spring and winter wheat grown in western Oregon, USA. Data used in this study were obtained from three different trials. For spring wheat rotation trials five spring wheat cultivars were used. Fertilizer N (16-16-16-4) at the rate of 140 kg ha/sup -1/ was applied at the time of planting. In small plot rotation trials five fertilizer treatments - 0, 50, 100,150 and 200 kg N ha/sup -1/ were used. Rotations include winter wheat following clover and winter wheat following oat. The N uptake and dry matter yield of winter wheat were also determined from unfertilized plots of wheat trial. The maximum N uptake for spring wheat and winter wheat were at 1100 and 2000 accumulated growing degree days (GDD), before Feekes 10, respectively. The maximum N uptake rate for spring wheat, 0.038 kg N GDD/sup -1/, occurred at 750 GDD and the peak N uptake was observed approximately 35 days after Feekes 2. Nitrogen uptake in winter wheat was significantly affected by rotations. (author)

Verification of “Channel-Probability Model” of Grain Yield Estimation

Directory of Open Access Journals (Sweden)

ZHENG Hong-yan

2016-07-01

Full Text Available The "channel-probability model" of grain yield estimation was verified and discussed systematically by using the grain production data from 1949 to 2014 in 16 typical counties, and 6 typical districts, and 31 provinces of China. The results showed as follows:(1Due to the geographical spatial scale was large enough, different climate zones and different meteorological conditions could compensated, and grain yield estimation error was small in the scale of nation. Therefore, it was not necessary to modify the grain yield estimation error by mirco-trend and the climate year types in the scale of nation. However, the grain yield estimation in the scale of province was located at the same of a climate zone,the scale was small, so the impact of the meteorological conditions on grain yield was less complementary than the scale of nation. While the spatial scale of districts and counties was smaller, accordingly the compensation of the impact of the meteorological conditions on grain yield was least. Therefore, it was necessary to use mrico-trend amendment and the climate year types amendment to modify the grain yield estimation in districts and counties.(2Mirco-trend modification had two formulas, generally, when the error of grain yield estimation was less than 10%, it could be modified by Y×(1-K; while the error of grain yield estimation was more than 10%, it could be modified by Y/(1+K.(3Generally, the grain estimation had 5 grades, and some had 7 grades because of large error fluctuation. The parameters modified of super-high yield year and super-low yield year must be depended on the real-time crop growth and the meteorological condition. (4By plenty of demonstration analysis, it was proved that the theory and method of "channel-probability model" was scientific and practical. In order to improve the accuracy of grain yield estimation, the parameters could be modified with micro-trend amendment and the climate year types amendment. If the

Formation of dust grains with impurities in red giant winds

Science.gov (United States)

Dominik, Carsten

1994-01-01

Among the several proposed carriers of diffuse interstellar bands (DIB's) are impurities in small dust grains, especially in iron oxide grains (Huffman 1977) and silicate grains (Huffman 1970). Most promising are single ion impurities since they can reproduce the observed band widths (Whittet 1992). These oxygen-rich grains are believed to originate mostly in the mass flows from red giants and in supernovae ejecta (e.g. Gehrz 1989). A question of considerable impact for the origin of DIB's is therefore, whether these grains are produced as mainly clean crystals or as some dirty materials. A formalism has been developed that allows tracking of the heterogeneous growth of a dust grain and its internal structure during the dust formation process. This formalism has been applied to the dust formation in the outflow from a red giant star.

Winter time burst of CO2 from the High Arctic soils of Svalbard

DEFF Research Database (Denmark)

Friborg, Thomas; Hansen, Birger; Elberling, Bo

of relatively few measurements which appear to give small and constant emission rates. Further, most studies of the processes behind winter time emission of CO2 conclude that the flux during this time of year can be linked to the respiratory release of CO2 from soil micro organisms, which is temperature...... the winter at a high arctic location in Svalbard (78°N). Measurements were conducted in the field during the winter season of 2004-2005 and show reliable and continuous measurements of CO2 fluxes down to a level of 0.01 ìmol m-2 s-1 and good correspondence with other types of soil chambers. Our results...... indicate that a substantial part of the annual CO2 emission from the ecosystem occur during the freeze in period, where more CO2 is emitted from the soil over a few weeks than the accumulated flux for the rest of the winter. During the coldest part of the...

Genetic gains in wheat in Turkey: Winter wheat for dryland conditions

Directory of Open Access Journals (Sweden)

Mesut Keser

2017-12-01

Full Text Available Wheat breeders in Turkey have been developing new varieties since the 1920s, but few studies have evaluated the rates of genetic improvement. This study determined wheat genetic gains by evaluating 22 winter/facultative varieties released for rainfed conditions between 1931 and 2006. The study was conducted at three locations in Turkey during 2008–2012, with a total of 21 test sites. The experimental design was a randomized complete block with four replicates in 2008 and 2009 and three replicates in 2010–2012. Regression analysis was conducted to determine genetic progress over time. Mean yield across all 21 locations was 3.34 t ha−1, but varied from 1.11 t ha−1 to 6.02 t ha−1 and was highly affected by moisture stress. Annual genetic gain was 0.50% compared to Ak-702, or 0.30% compared to the first modern landmark varieties. The genetic gains in drought-affected sites were 0.75% compared to Ak-702 and 0.66% compared to the landmark varieties. Modern varieties had both improved yield potential and tolerance to moisture stress. Rht genes and rye translocations were largely absent in the varieties studied. The number of spikes per unit area decreased by 10% over the study period, but grains spike−1 and 1000-kernel weight increased by 10%. There were no significant increases in harvest index, grain size, or spike fertility, and no significant decrease in quality over time. Future use of Rht genes and rye translocations in breeding programs may increase yield under rainfed conditions. Keywords: Genetic gain, Rainfed wheat production, Winter wheat, Yield

The Impact of Sowing Technology on Ponderal Features of Winter Wheat Seeds in Timişoara

Directory of Open Access Journals (Sweden)

Marcela Dragoş

2011-10-01

Full Text Available Wheat is a grass, originally from the Fertile Crescent region of the Near East, but now cultivated worldwide. The paper presents the results obtained in the last two years of experience, about the influence of sowing technology on the ponderal features of the winter wheat seeds. The experimental parcels were laid down in a randomized complete block design with three replications in the pedo-climatic conditions of Timişoara. The purpose of the research is to determine the influence of some sowing links on the thousand grain mass and hectoliter mass. The average data obtained after two years of study indicate an increase of about 2 % of the thousand grain mass and hectoliter mass on the second sowing period (16-31 Octoberand a distinctive decrease of 2-3% on the fourth sowing period(16-30 November. During the two years of experience the row distance and the sowing density had a negative impact on both thousand grain mass and hectoliter mass in both variants compared with the control variant, the difference being statistical significant.

Effects of exogenous ABA application on post-anthesis dry matter redistribution and grain starch accumulation of winter wheat with different staygreen characteristics

Directory of Open Access Journals (Sweden)

Dongqing Yang

2014-04-01

Full Text Available The objective of this study was to investigate whether and how exogenous abscisic acid (ABA is involved in mediating starch accumulation in the grain and redistribution of carbohydrates during grain filling of two wheat cultivars with different staygreen characteristics. At blooming stage, plants of Wennong 6 (a staygreen cultivar and Jimai 20 (control were sprayed with 10 mg L− 1 abscisic acid (ABA for 3 days. The application of ABA significantly (P < 0.05 increased grain filling rate, starch accumulation rate and content, remobilization of dry matters to kernels, and 1000-grain weight of the two cultivars. Exogenous ABA markedly (P < 0.05 increased grain yield at maturity, and Wennong 6 and Jiami 20 showed 14.14% and 4.86% higher compared yield than the control. Dry matter accumulation after anthesis of Wennong 6 was also significantly (P < 0.05 influenced by exogenous ABA, whereas that of Jimai 20 was unchanged. Application of ABA increased endogenous zeatin riboside (ZR content 7 days after anthesis (DAA, and spraying ABA significantly increased endogenous indole-3-acetic acid (IAA and ABA contents from 7 to 21 DAA and decreased gibberellin (GA3 content at 14 DAA, but increased GA3 content from 21 to 35 DAA. The results suggested that increased yield of staygreen was due to greater starch assimilation owing to a higher filling rate and longer grain-filling duration.

Coarse-graining stochastic biochemical networks: adiabaticity and fast simulations

Energy Technology Data Exchange (ETDEWEB)

Nemenman, Ilya [Los Alamos National Laboratory; Sinitsyn, Nikolai [Los Alamos National Laboratory; Hengartner, Nick [Los Alamos National Laboratory

2008-01-01

We propose a universal approach for analysis and fast simulations of stiff stochastic biochemical kinetics networks, which rests on elimination of fast chemical species without a loss of information about mesoscoplc, non-Poissonian fluctuations of the slow ones. Our approach, which is similar to the Born-Oppenhelmer approximation in quantum mechanics, follows from the stochastic path Integral representation of the cumulant generating function of reaction events. In applications with a small number of chemIcal reactions, It produces analytical expressions for cumulants of chemical fluxes between the slow variables. This allows for a low-dimensional, Interpretable representation and can be used for coarse-grained numerical simulation schemes with a small computational complexity and yet high accuracy. As an example, we derive the coarse-grained description for a chain of biochemical reactions, and show that the coarse-grained and the microscopic simulations are in an agreement, but the coarse-gralned simulations are three orders of magnitude faster.

Accretion growth of water-ice grains in astrophysically-relevant dusty plasma experiment

Science.gov (United States)

Chai, Kil-Byoung; Marshall, Ryan; Bellan, Paul

2016-10-01

The grain growth process in the Caltech water-ice dusty plasma experiment has been studied using a high-speed camera equipped with a long-distance microscope lens. It is found that (i) the ice grain number density decreases four-fold as the average grain length increases from 20 to 80 um, (ii) the ice grain length has a log-normal distribution rather than a power-law dependence, and (iii) no collisions between ice grains are apparent. The grains have a large negative charge so the agglomeration growth is prevented by their strong mutual repulsion. It is concluded that direct accretion of water molecules is in good agreement with the observed ice grain growth. The volumetric packing factor of the ice grains must be less than 0.25 in order for the grain kinetic energy to be sufficiently small to prevent collisions between ice grains; this conclusion is consistent with ice grain images showing a fractal character.

The response of winter wheat to water stress and nitrogen fertilizer use efficiency

International Nuclear Information System (INIS)

Wang, F.; Qi, M.; Wang, H.; Changjiu, Z.

1995-01-01

The response of winter wheat to water stress imposed at different crop growth stages by deficit irrigation and fertilizer use under several schemes of irrigation were evaluated on fine sandy soil and sand loam soil. The results showed that according to grain yield response factor K, the order of sensitive growth stages of winter wheat to water stress in decreasing sequence were booting to flowering ( K= 0.90), winter afterward to booting ( K= 0.69), flowering to milking ( K= 0.44) and milking to ripening ( K= 0.25). Field water efficiency would get 16.7 kg/mm.ha when no water stress in growth period, and when water stress has occurred in some growth stages, the value of it decreased by 5 - 20 percent. It was also found that high fertilizer application rate without split application would not significantly influence the yield on fine sandy soil. But schedule of irrigation affected the translocation of nitrogen in the plant. When water stress occurred in later growth stage, the ratio of NUE in gain to straw decreased, and fertilizer was available for crop only about one month after fertilizer application, excessive fertilizer rate would result in decrease of NUE by leaching of nitrogen in sandy soil. Total recovery of fertilizer at harvest was half amount of application. 6 refs; 10 tabs; ( author)

Hall measurements and grain-size effects in polycrystalline silicon

International Nuclear Information System (INIS)

Ghosh, A.K.; Rose, A.; Maruska, H.P.; Eustace, D.J.; Feng, T.

1980-01-01

The effects of grain size on Hall measurements in polycrystalline silicon are analyzed and interpreted, with some modifications, using the model proposed by Bube. This modified model predicts that the measured effective Hall voltage is composed of components originating from the bulk and space-charge regions. For materials with large grain sizes, the carrier concentration is independent of the intergrain boundary barrier, whereas the mobility is dependent on it. However, for small grains, both the carrier density and mobility depend on the barrier. These predictions are consistent with experimental results of mm-size Wacker and μm-size neutron-transmutation-doped polycrystalline silicon

IFPE/GBGI, Grain-Bubble Gas Inter-linkage

International Nuclear Information System (INIS)

2007-01-01

Description: The fuel microstructure examination at the thermocouple tips in the lower and upper part of a steady-state irradiated experimental fuel rod with different as fabricated fuel-to-clad gaps in these two regions revealed on-set of grain boundary gas bubble precipitation in the fuel center of the small-gap/low-temperature region (lower part) and developed inter-linkage in the fuel center of the large-gap/high-temperature region (upper part). By use of a diffusion model and the measured temperatures, corresponding grain boundary gas 'concentrations' were calculated

Black brant from Alaska staging and wintering in Japan

Science.gov (United States)

Derksen, Dirk V.; Bollinger, K.S.; Ward, David H.; Sedinger, J.S.; Miyabayashi, Y.

1996-01-01

Black brant (Branta bernicla nigricans) nest in colonies in arctic Canada, Alaska, and Russia (Derksen and Ward 1993, Sedinger et al. 1993). Virtually the entire population stages in fall at Izembek Lagoon near the tip of the Alaska Peninsula (Bellrose 1976) before southward migration (Dau 1992) to winter habitats in British Columbia, Washington, Oregon, California, and Baja California (Subcommittee on Black Brant 1992). A small number of black brant winter in Japan, Korea, and China (Owen 1980). In Japan 3,000–5,000 brant of unknown origin stop over in fall, and a declining population (in the northern islands (Brazil 1991, Miyabayashi et al. 1994). Here, we report sightings of brant in Japan that were marked in Alaska and propose a migration route based on historical and recent observations and weather patterns.

ITCZ and ENSO pacing on East Asian winter monsoon variation during the Holocene: Sedimentological evidence from the Okinawa Trough

Science.gov (United States)

Zheng, Xufeng; Li, Anchun; Wan, Shiming; Kao, Shuhji; Kuhn, Gerhard

2016-04-01

Deep-sea fan sediments provide an excellent geological archive for paleoenvironment reconstruction. Grain size, clay mineral and elemental (Ti, Fe, Ca) compositions were measured for a core retrieved from a submarine fan in the Okinawa Trough. Varimax-rotated Principal Component Analysis (V-PCA) on time-evolution of grain size spectrum reveals that, since the Holocene, sediment was transported mainly by the benthic nepheloid layer (33%) and upper layers (33%) which is driven by the East Asian winter monsoon (EAWM). The intensification of the Kuroshio Current during the Holocene, masks the fluvial signal of the summer monsoon and obstructs clay minerals derived from the Yellow River, a major contributor prior to 12 ka BP. A new grain size index (GSI), which represents the EAWM well, exhibits a negative correlation with the δ18O record in Dongge Cave, China during the Holocene when sea level was relatively steady. This anticorrelation suggests the southward migration of the Intertropical Convergence Zone (ITCZ). The consistency among our records and rainfall records in Peru, Ti counts in the Cariaco Basin, monsoon records in Oman and the averaged summer insolation pattern at 30°N further support the ITCZ's impact on monsoon systems globally. Cross-Correlation Analyses for GSI and log(Ti/Ca) against δ18O record in Dongge Cave reveal a decoupling between the East Asian winter and summer monsoon during 5500-2500 cal yr BP, with greater complexity in the last 2500 years. This can be attributed to exacerbated ENSO mode fluctuations and possibly anthropogenic interference superimposed on insolation and ITCZ forcing.

The Relationship Between Debris and Grain Growth in Polycrystalline Ice

Science.gov (United States)

Rivera, A.; McCarthy, C.

2017-12-01

An understanding of the mechanisms of ice flow, as well as the factors that affect it, must be improved in order to make more accurate predictions of glacial melting rates, and hence, sea level rise. Both field and laboratory studies have made an association between smaller grain sizes of ice and more rapid deformation. Therefore, it is essential to understand the different factors that affect grain size. Observations from ice cores have shown a correlation between debris content in layers of ice with smaller grain sizes, whereas layers with very little debris have larger grain sizes. Static grain growth rates for both pure ice and ice containing bubbles are well constrained, but the effect of small rock/dust particles has received less attention. We tested the relationship between debris and grain growth in polycrystalline ice with controlled annealing at -5°C and microstructural characterization. Three samples, two containing fine rock powder and one without, were fabricated, annealed, and imaged over time. The samples containing powder had different initial grain sizes due to solidification temperature during fabrication. Microstructural analysis was done on all samples after initial fabrication and at various times during the anneal using a light microscope housed in a cold room. Microstructural images were analyzed by the linear-intercept method. When comparing average grain size over time between pure ice and ice with debris, it was found that the rate of growth for the pure ice was larger than the rate of growth for the ice with debris at both initial grain sizes. These results confirm the observations seen in nature, and suggest that small grain size is indeed influenced by debris content. By understanding this, scientists could gain a more in-depth understanding of internal ice deformation and the mechanisms of ice flow. This, in turn, helps improve the accuracy of glacial melting predictions, and sea level rise in the future.

Kuiper Belt Dust Grains as a Source of Interplanetary Dust Particles

Science.gov (United States)

Liou, Jer-Chyi; Zook, Herbert A.; Dermott, Stanley F.

1996-01-01

The recent discovery of the so-called Kuiper belt objects has prompted the idea that these objects produce dust grains that may contribute significantly to the interplanetary dust population. In this paper, the orbital evolution of dust grains, of diameters 1 to 9 microns, that originate in the region of the Kuiper belt is studied by means of direct numerical integration. Gravitational forces of the Sun and planets, solar radiation pressure, as well as Poynting-Robertson drag and solar wind drag are included. The interactions between charged dust grains and solar magnetic field are not considered in the model. Because of the effects of drag forces, small dust grains will spiral toward the Sun once they are released from their large parent bodies. This motion leads dust grains to pass by planets as well as encounter numerous mean motion resonances associated with planets. Our results show that about 80% of the Kuiper belt grains are ejected from the Solar System by the giant planets, while the remaining 20% of the grains evolve all the way to the Sun. Surprisingly, the latter dust grains have small orbital eccentricities and inclinations when they cross the orbit of the Earth. This makes them behave more like asteroidal than cometary-type dust particles. This also enhances their chances of being captured by the Earth and makes them a possible source of the collected interplanetary dust particles; in particular, they represent a possible source that brings primitive/organic materials from the outer Solar System to the Earth. When collisions with interstellar dust grains are considered, however, Kuiper belt dust grains around 9 microns appear likely to be collisionally shattered before they can evolve toward the inner part of the Solar System. The collision destruction can be applied to Kuiper belt grains up to about 50 microns. Therefore, Kuiper belt dust grains within this range may not be a significant part of the interplanetary dust complex in the inner Solar

Influence of age and sex on winter site fidelity of sanderlings Calidris alba

Directory of Open Access Journals (Sweden)

Pedro M. Lourenço

2016-09-01

Full Text Available Many migratory bird species show high levels of site fidelity to their wintering sites, which confers advantages due to prior knowledge, but may also limit the ability of the individual to move away from degrading sites or to detect alternative foraging opportunities. Winter site fidelity often varies among age groups, but sexual differences have seldom been recorded in birds. We studied a population of individually colour-marked sanderlings wintering in and around the Tejo estuary, a large estuarine wetland on the western coast of Portugal. For 160 individuals, sighted a total of 1,249 times between November 2009 and March 2013, we calculated the probability that they moved among five distinct wintering sites and how this probability is affected by distance between them. To compare site fidelity among age classes and sexes, as well as within the same winter and over multiple winters, we used a Site Fidelity Index (SFI. Birds were sexed using a discriminant function based on biometrics of a large set of molecularly sexed sanderlings (n = 990. The vast majority of birds were observed at one site only, and the probability of the few detected movements between sites was negatively correlated with the distance among each pair of sites. Hardly any movements were recorded over more than 15 km, suggesting small home ranges. SFI values indicated that juveniles were less site-faithful than adults which may reflect the accumulated knowledge and/or dominance of older animals. Among adults, females were significantly less site faithful than males. A sexual difference in winter site fidelity is unusual in shorebirds. SFI values show site-faithfulness is lower when multiple winters were considered, and most birds seem to chose a wintering site early in the season and use that site throughout the winter. Sanderlings show a very limited tendency to explore alternative wintering options, which might have implications for their survival when facing habitat change

Film grain synthesis and its application to re-graining

Science.gov (United States)

Schallauer, Peter; Mörzinger, Roland

2006-01-01

Digital film restoration and special effects compositing require more and more automatic procedures for movie regraining. Missing or inhomogeneous grain decreases perceived quality. For the purpose of grain synthesis an existing texture synthesis algorithm has been evaluated and optimized. We show that this algorithm can produce synthetic grain which is perceptually similar to a given grain template, which has high spatial and temporal variation and which can be applied to multi-spectral images. Furthermore a re-grain application framework is proposed, which synthesises based on an input grain template artificial grain and composites this together with the original image content. Due to its modular approach this framework supports manual as well as automatic re-graining applications. Two example applications are presented, one for re-graining an entire movie and one for fully automatic re-graining of image regions produced by restoration algorithms. Low computational cost of the proposed algorithms allows application in industrial grade software.

Dust grain charging in a wake of other grains

International Nuclear Information System (INIS)

Miloch, W. J.; Block, D.

2012-01-01

The charging of dust grain in the wake of another grains in sonic and supersonic collisionless plasma flows is studied by numerical simulations. We consider two grains aligned with the flow, as well as dust chains and multiple grain arrangements. It is found that the dust charge depends significantly on the flow speed, distance between the grains, and the grain arrangement. For two and three grains aligned, the charges on downstream grains depend linearly on the flow velocity and intergrain distance. The simulations are carried out with DiP3D, a three dimensional particle-in-cell code with both electrons and ions represented as numerical particles [W. J. Miloch et al., Phys. Plasmas 17, 103703 (2010)].

Winter maintenance performance measure.

Science.gov (United States)

2016-01-01

The Winter Performance Index is a method of quantifying winter storm events and the DOTs response to them. : It is a valuable tool for evaluating the States maintenance practices, performing post-storm analysis, training : maintenance personnel...

Use of optical sensor for in-season nitrogen management and grain yield prediction in maize

Directory of Open Access Journals (Sweden)

Bandhu Raj Baral

2015-12-01

Full Text Available Precision agriculture technologies have developed optical sensors which can determine plant’s normalized difference vegetation index (NDVI.To evaluate the relationship between maize grain yield and early season NDVI readings, an experiment was conducted at farm land of National Maize Research Program, Rampur, Chitwan during winter season of 2012. Eight different levels of N 0, 30, 60, 90, 120, 150, 180 and 210 kg N/ha were applied for hybrid maize RML 32 × RML 17 to study grain yield response and NDVI measurement. Periodic NDVI was measured at 10 days interval from 55 days after sowing (DAS to 115 DAS by using Green seeker hand held crop sensor. Periodic NDVI measurement taken at a range of growing degree days (GDD was critical for predicting grain yield potential. Poor exponential relationship existed between NDVI from early reading measured before 208 GDD (55 DAS and grain yield. At the 261GDD (65DAS a strong relationship (R2 = 0.70 was achieved between NDVI and grain yield. Later sensor measurements after 571 GDD (95DAS failed to distinguish variation in green biomass as a result of canopy closure. N level had significantly influenced on NDVI reading, measured grain yield, calculated in season estimated yield (INSEY, predicted yield with added N (YPN, response index (RI and grain N demand. Measuring NDVI reading by GDD (261–571 GDD allow a practical window of opportunity for side dress N applications. This study showed that yield potential in maize could be accurately predicted in season with NDVI measured with the Green Seeker crop sensor.

Impact of energetic cosmic-ray ions on astrophysical ice grains

International Nuclear Information System (INIS)

Mainitz, Martin; Anders, Christian; Urbassek, Herbert M.

2017-01-01

Highlights: • We use the REAX potential to model dissociations and reactions. • An ice grain consisting of a mixture of small molecules is considered. • The passage of a cosmic-ray ion initiates an ion track. • The track induces a shock wave and disintegrates the grain. • Abundant fragments and reaction products are detected. - Abstract: Using molecular-dynamics simulation with REAX potentials, we study the consequences of cosmic-ray ion impact on ice grains. The grains are composed of a mixture of H_2O, CO_2, NH_3, and CH_3OH molecules. Due to the high energy deposition of the cosmic-ray ion, 5 keV/nm, a strong pressure wave runs through the grain, while the interior of the ion track gasifies. Abundant molecular dissociations occur; reactions of the fragments form a variety of novel molecular product species.

THE EFFECTS OF GRAIN SIZE AND TEMPERATURE DISTRIBUTIONS ON THE FORMATION OF INTERSTELLAR ICE MANTLES

Energy Technology Data Exchange (ETDEWEB)

Pauly, Tyler; Garrod, Robin T., E-mail: tap74@cornell.edu [Cornell Center for Astrophysics and Planetary Science, Cornell University, Ithaca, NY 14853-6801 (United States)

2016-02-01

Computational models of interstellar gas-grain chemistry have historically adopted a single dust-grain size of 0.1 micron, assumed to be representative of the size distribution present in the interstellar medium. Here, we investigate the effects of a broad grain-size distribution on the chemistry of dust-grain surfaces and the subsequent build-up of molecular ices on the grains, using a three-phase gas-grain chemical model of a quiescent dark cloud. We include an explicit treatment of the grain temperatures, governed both by the visual extinction of the cloud and the size of each individual grain-size population. We find that the temperature difference plays a significant role in determining the total bulk ice composition across the grain-size distribution, while the effects of geometrical differences between size populations appear marginal. We also consider collapse from a diffuse to a dark cloud, allowing dust temperatures to fall. Under the initial diffuse conditions, small grains are too warm to promote grain-mantle build-up, with most ices forming on the mid-sized grains. As collapse proceeds, the more abundant, smallest grains cool and become the dominant ice carriers; the large population of small grains means that this ice is distributed across many grains, with perhaps no more than 40 monolayers of ice each (versus several hundred assuming a single grain size). This effect may be important for the subsequent processing and desorption of the ice during the hot-core phase of star formation, exposing a significant proportion of the ice to the gas phase, increasing the importance of ice-surface chemistry and surface–gas interactions.

The Effects of Grain Size and Temperature Distributions on the Formation of Interstellar Ice Mantles

Science.gov (United States)

Pauly, Tyler; Garrod, Robin T.

2016-02-01

Computational models of interstellar gas-grain chemistry have historically adopted a single dust-grain size of 0.1 micron, assumed to be representative of the size distribution present in the interstellar medium. Here, we investigate the effects of a broad grain-size distribution on the chemistry of dust-grain surfaces and the subsequent build-up of molecular ices on the grains, using a three-phase gas-grain chemical model of a quiescent dark cloud. We include an explicit treatment of the grain temperatures, governed both by the visual extinction of the cloud and the size of each individual grain-size population. We find that the temperature difference plays a significant role in determining the total bulk ice composition across the grain-size distribution, while the effects of geometrical differences between size populations appear marginal. We also consider collapse from a diffuse to a dark cloud, allowing dust temperatures to fall. Under the initial diffuse conditions, small grains are too warm to promote grain-mantle build-up, with most ices forming on the mid-sized grains. As collapse proceeds, the more abundant, smallest grains cool and become the dominant ice carriers; the large population of small grains means that this ice is distributed across many grains, with perhaps no more than 40 monolayers of ice each (versus several hundred assuming a single grain size). This effect may be important for the subsequent processing and desorption of the ice during the hot-core phase of star formation, exposing a significant proportion of the ice to the gas phase, increasing the importance of ice-surface chemistry and surface-gas interactions.

Energy and tannin extract supplementation for dairy cows on annual winter pastures

Directory of Open Access Journals (Sweden)

Tiago Pansard Alves

2017-05-01

Full Text Available Energy supplementation can increase the consumption of metabolizable energy and substrate for microbial growth, while condensed tannins aid in increasing the duodenal flow of foodborne metabolizable proteins. The objective of this study was to evaluate the effects of energy supplementation and the inclusion of tannin extract (TE from Acacia mearnsii (Weibull Black, Tanac S. A., Montenegro, Brazil on the production performance of dairy cows grazing on winter pastures. Nine multiparous Holstein cows in mid lactation were distributed in a 3 × 3 Latin square experimental design over three periods of 28 days (21 adaptation and 7 sampling. The treatments were: without supplementation (WS, supplementation with 4 kg of corn grain (CG, and corn grain + 80 g of tannin extract (TE. The dry matter (DM intake from pastures was similar among treatments, but the consumption of DM of the supplement was higher in the CG treatment than that in the TE treatment. The total DM intake was higher for the supplemented animals (17.3 kg?day-1 than that for the unsupplemented animals (14.9 kg?day-1 and in the TE treatment (17.7 kg?day-1 than in the CG treatment (16.7 kg day-1. Milk production increased from the unsupplemented to the supplemented animals (20.9 to 23.5 kg, respectively, while the content of urea N in the milk decreased (12.6 to 10.5 mg?100 mL-1, respectively. There were no differences in milk production or content of milk urea N between the CG and TE treatments. Energy supplementation is a tool for improving the nutritional profile and the performance of dairy cows in mid lactation grazing on annual winter pastures, while tannin extract aids in improving the energy balance.

Efficiency of Estonian grain farms in 2000 2004

Directory of Open Access Journals (Sweden)

N. VASILIEV

2008-12-01

Full Text Available The aim of this study is to analyse the efficiency of Estonian grain farms after Estonia’s transition to a market economy and during the accession period to the European Union (EU. The non-parametric method Data Envelopment Analysis (DEA was used to estimate the total technical, pure technical and scale efficiency of Estonian grain farms in 2000–2004. Mean total technical efficiency varied from 0.70 to 0.78. Of the grain farms 62% are operating under increasing returns to scale. Solely based on the DEA model it is not possible to determine optimum farm scale and the range of Estonian farm sizes operating efficiently is extensive. The most pure technically efficient farms were the smallest and the largest but the productivity of small farms is low compared to larger farms because of their small scale. Therefore, they are the least competitive. Since pre-accession period to the EU, large input slacks of capital have replaced the former excessive use of labour and land. This raises the question about the effects on efficiency of the EU’s investment support schemes in new member states.;

Estimating winter survival of winter wheat by simulations of plant frost tolerance

NARCIS (Netherlands)

Bergjord Olsen, A.K.; Persson, T.; Wit, de A.; Nkurunziza, L.; Sindhøj, E.; Eckersten, H.

2018-01-01

Based on soil temperature, snow depth and the grown cultivar's maximum attainable level of frost tolerance (LT50c), the FROSTOL model simulates development of frost tolerance (LT50) and winter damage, thereby enabling risk calculations for winter wheat survival. To explore the accuracy of this

Effects of grain size and humidity on fretting wear in fine-grained alumina, Al{sub 2}O{sub 3}/TiC, and zirconia

Energy Technology Data Exchange (ETDEWEB)

Krell, A. [Fraunhofer Inst. for Ceramic Technologies and Sintered Materials, Dresden (Germany); Klaffke, D. [Federal Inst. for Materials Research and Testing, Berlin (Germany)

1996-05-01

Friction and wear of sintered alumina with grain sizes between 0.4 and 3 {micro}m were measured in comparison with Al{sub 2}O{sub 3}/TiC composites and with tetragonal ZrO{sub 2} (3 mol% Y{sub 2}O{sub 3}). The dependence on the grain boundary toughness and residual microstresses is investigated, and a hierarchical order of influencing parameters is observed. In air, reduced alumina grain sizes improve the micromechanical stability of the grain boundaries and the hardness, and reduced wear is governed by microplastic deformation, with few pullout events. Humidity and water slightly reduce the friction of all of the investigated ceramics. In water, this effect reduces the wear of coarser alumina microstructures. The wear of aluminas and of the Al{sub 2}O{sub 3}/TiC composite is similar; it is lower than observed in zirconia, where extended surface cracking occurs at grain sizes as small as 0.3 {micro}m.

The Relationship Between Microscopic Grain Surface Structure and the Dynamic Capillary-Driven Advance of Water Films over Individual Dry Natural Sand Grains

Science.gov (United States)

Kibbey, T. C. G.; Adegbule, A.; Yan, S.

2017-12-01

The movement of nonvolatile solutes in unsaturated porous media at low water contents depends on transport in surface-associated water films. The focus of the work described here was on studying solute movement in water films advancing by capillary forces over initially-dry grain surfaces, to understand how microscopic surface roughness features influence the initial velocity of water film advance. For this work, water containing a non-adsorbing conservative tracer was used to track the movement of advancing water films. A stainless steel capillary tube connected to an external reservoir a fixed distance below the grain surface was used to transmit solution to the grain surface under negative pressure (positive capillary pressure), consistent with conditions that might be expected in the unsaturated zone. The small internal diameter of the capillary prevents solution from draining out of the capillary back into the reservoir. When the capillary is contacted with a grain surface, capillary forces that result from contact between the fluid and the rough grain surface cause water films to wick across the grain surface. Multiple experiments were conducted on the same grain, rotating the grain and varying the capillary contact point around the circumference of the grain. Imaging was conducted at fixed intervals using an automated Extended Depth of Field (EDF) imaging system, and images were analyzed to determine initial velocity. Grain surfaces were then characterized through scanning electron microscope (SEM) imaging, using a hybrid stereoscopic reconstruction method designed to extract maximum detail in creating elevation maps of geologic surfaces from tilted pairs of SEM images. The resulting elevation maps were used to relate surface roughness profiles around the grain with initial velocities. Results suggest that velocity varies significant with contact point around an individual grain, and correlates quantitatively with the local grain surface structure

Incorporating Yearly Derived Winter Wheat Maps Into Winter Wheat Yield Forecasting Model

Science.gov (United States)

Skakun, S.; Franch, B.; Roger, J.-C.; Vermote, E.; Becker-Reshef, I.; Justice, C.; Santamaría-Artigas, A.

2016-01-01

Wheat is one of the most important cereal crops in the world. Timely and accurate forecast of wheat yield and production at global scale is vital in implementing food security policy. Becker-Reshef et al. (2010) developed a generalized empirical model for forecasting winter wheat production using remote sensing data and official statistics. This model was implemented using static wheat maps. In this paper, we analyze the impact of incorporating yearly wheat masks into the forecasting model. We propose a new approach of producing in season winter wheat maps exploiting satellite data and official statistics on crop area only. Validation on independent data showed that the proposed approach reached 6% to 23% of omission error and 10% to 16% of commission error when mapping winter wheat 2-3 months before harvest. In general, we found a limited impact of using yearly winter wheat masks over a static mask for the study regions.

Winter weather demand considerations.

Science.gov (United States)

2015-04-01

Winter weather has varied effects on travel behavior. Using 418 survey responses from the Northern Virginia : commuting area of Washington, D.C. and binary logit models, this study examines travel related changes under : different types of winter wea...

Controlling factors of stratigraphic occurrences of fine-grained turbidites: Examples from the Japanese waters

Science.gov (United States)

Ikehara, K.

2017-12-01

Fine-grained turbidite has been used for subaqueous paleoseismology, and has been recognized from shallow- to deep-water environments around the Japanese islands. Stratigraphic occurrence of fine-grained turbidites in the deepest Beppu Bay, south Japan, with its water depth of 75 m suggest clear influence of sea-level changes. Turbidite frequency was high during the post glacial sea-level rising and last 2.7 ka, and was low during the Holocene maximum sea-level highstand (5.3-2.7 ka). Retreat and progress of coastal delta front of the nearby river might affect the sediment supply to the deepest basin. On the other hand, fine-grained turbidites found in the forearc basins ( 3500 and 4500 m in water depths) and trench floor ( 6000 m in water depth) along the southern Ryukyu arc have no clear relation with sea-level changes. Sediment and bathymetric characteristics suggest that origin of these fine-grained turbidites is Taiwan. Remarkable tectonic uplift of Taiwanese coast with small mountainous rivers and narrow shelf may produce the continuous supply of fine-grained turbidites in this area. The Japan Trench floor composes of a series of small basins reflecting subducting horst-graben structure of the Pacific Plate. Each small basin acts as a natural sediment trap receiving the earthquake-induced turbidity currents. Thick fine-grained turbidites are also occurred in the small basins in the Japan Trench floor ( 7500 m in water depth). These are most likely induced by huge earthquakes along the Japan Trench. Thus, their stratigraphic occurrences might have close relation with recurrence of huge earthquakes in the past.

Stochastic diffusion of dust grains by the interplanetary magnetic field

International Nuclear Information System (INIS)

Hassan, M.H.A.; Wallis, M.K.

1983-10-01

The effects of the sectored Interplanetary Magnetic Field on charged dust grains orbiting around the sun under radiation pressure and Poynting-Robertson drag forces are examined for initially circular and non-inclined orbits. The distribution function of the charged grains satisfies a Fokker-Planck equation in which the sectored field is taken as a source of stochastic impulses. By adopting the integrals of the impulse-free motion as variable parameters, the Fokker-Planck equation can be properly treated as a diffusion equation. Analytic solutions of the resulting diffusion equation show that dust grains injected near the ecliptic plane are scattered strongly to high helio-latitudes. The scattering is more pronounced for small grains injected at large distances from the Sun. (author)

Effects of dirty snow in nuclear winter simulations

International Nuclear Information System (INIS)

Vogelmann, A.M.; Robock, A.; Ellingson, R.G.

1988-01-01

A large-scale nuclear war would inject smoke into the atmosphere from burning forests, cities, and industries in targeted areas. This smoke could fall out onto snow and ice and would lower cryospheric albedos by as much as 50%. A global energy balance climate model is used to investigate the maximum effect these ''dirty snow'' albedos have on the surface temperature in nuclear winter simulations which span several years. These effects are investigated for different nuclear winter scenarios, snow precipitation rates, latitudinal distributions of smoke, and seasonal timings. We find that dirty snow, in general, would have a small temperature effect at mid- and low latitudes but could have a large temperature effect at polar latitudes, particularly if the soot is able to reappear significantly in later summers. Factors which limit the climatic importance of the dirty snow are (1) the dirty snow albedo is lowest when the atmosphere still contains a large amount of light-absorbing smoke; (2) even with dirty snow, sea ice areas can still increase, which helps maintain colder temperatures through the sea ice thermal inertial feedback; (3) the snow and ice areas affected by the dirty snow albedos are largest when there is little seasonal solar insolation; and (4) the area affected by the dirty snow is relatively small under all circumstances. copyright American Geophysical Union 1988

Grain-filling duration and grain yield relationships in wheat mutants

International Nuclear Information System (INIS)

Larik, A.S.

1987-01-01

Nine stable mutants of bread wheat along with their mother cultivars were investigated for grain-filling characteristics in relation to grain yield. Significant differences among mutants for grain-filling duration and grain-filling index were observed. Inspite of the consistent differences in grain-filling duration there was no significant association between grain-filling duration and grain yield in C-591 and Nayab mutants. Failure to detect an yield advantage due to differences in grain-filling duration in these genotypes suggests that any advantage derived from alteration of grain-filling period may have been outweighed by the coincident changes in length of the vegetative period. Other factors such as synchrony of anthesis may have limited out ability to find an association between grainfilling duration and grain yield. On the contrary, significant association between grain-filling duration and grain yield displayed by indus-66 indus-66 mutants derived from gamma rays, shows the ability of gamma rays to induce functional alternations in the pattern of gene arrangements controlling these traits. Thus, the vaability observed in these physiological traits suggests that selection for these traits could be useful in improving grain yield. (author)

Genotype, environment, seeding rate, and top-dressed nitrogen effects on end-use quality of modern Nebraska winter wheat.

Science.gov (United States)

Bhatta, Madhav; Regassa, Teshome; Rose, Devin J; Baenziger, P Stephen; Eskridge, Kent M; Santra, Dipak K; Poudel, Rachana

2017-12-01

Fine-tuning production inputs such as seeding rate, nitrogen (N), and genotype may improve end-use quality of hard red winter wheat (Triticum aestivium L.) when growing conditions are unpredictable. Studies were conducted at the Agronomy Research Farm (ARF; Lincoln, NE, USA) and the High Plains Agricultural Laboratory (HPAL; Sidney, NE, USA) in 2014 and 2015 in Nebraska, USA, to determine the effects of genotype (6), environment (4), seeding rate (3), and flag leaf top-dressed N (0 and 34 kg N ha -1 ) on the end-use quality of winter wheat. End-use quality traits were influenced by environment, genotype, seeding rate, top-dressed N, and their interactions. Mixograph parameters had a strong correlation with grain volume weight and flour yield. Doubling the recommended seeding rate and N at the flag leaf stage increased grain protein content by 8.1% in 2014 and 1.5% in 2015 at ARF and 4.2% in 2014 and 8.4% in 2015 at HPAL. The key finding of this research is that increasing seeding rates up to double the current recommendations with N at the flag leaf stage improved most of the end-use quality traits. This will have a significant effect on the premium for protein a farmer could receive when marketing wheat. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.

Residual N effect of long-term applications of cattle slurry using winter wheat as test crop

DEFF Research Database (Denmark)

Suarez, Alfonso; Thomsen, Ingrid Kaag; Rasmussen, Jim

2018-01-01

) as reference treatments. In the test years, the customary nutrient treatments were withheld and each plot divided into six subplots randomly allocated increasing rates of mineral fertilizer N (0–250 kg N ha−1). The winter wheat yielded more in the first test year due to crop rotational effects and more benign...... climatic conditions, substantiating that more test years are needed when estimating residual N effects. The residual value of N added previously with NPK was negligible. In the first year, grain yields at N optimum were similar for NPK and SLU, but the amount of fertilizer N needed to reach optimum yield...... in cattle slurry (50, 100 and 150 kg total-N ha−1 termed ½, 1 and 1½ SLU), we estimated the residual N value over two consecutive growth periods (2014/2015 and 2015/2016). We used winter wheat as test crop and soils with a history of mineral fertilizers only (1 PK (no N)) and 1 NPK (100 kg N ha−1...

Effects of feeding blends of grains naturally contaminated with Fusarium mycotoxins on small intestinal morphology of turkeys.

Science.gov (United States)

Girish, C K; Smith, T K

2008-06-01

An experiment was conducted to investigate the effects of feeding grains naturally contaminated with Fusarium mycotoxins on morphometric indices of duodenum, jejunum, and ileum in turkeys. The possible preventative effect of a polymeric glucomannan mycotoxin adsorbent (GMA) was also determined. Three hundred 1-d-old male turkey poults were fed wheat, corn, and soybean meal-based starter (0 to 3 wk), grower (4 to 6 wk), developer (7 to 9 wk), and finisher (10 to 12 wk) diets formulated with control grains, contaminated grains, and contaminated grains + 0.2% GMA. Morphometric indices were measured at the end of each growth phase and included villus height (VH), crypt depth, villus width, thicknesses of submucosa and muscularis, villus-to-crypt ratio, and apparent villus surface area (AVSA). At the end of the starter phase, feedborne mycotoxins significantly decreased the VH in the duodenum, and supplementation of the contaminated diet with GMA prevented this effect. The feeding of contaminated grains also reduced (P effects in jejunum and ileum. No effects of diets were seen on morphometric variables at the end of the developer and finisher phases. It was concluded that consumption of grains naturally contaminated with Fusarium mycotoxins results in adverse effects on intestinal morphology during early growth phases of turkeys, and GMA can prevent many of these effects.

Something from nothing: self-charging of identical grains

Science.gov (United States)

Shinbrot, Troy; Yoshimatsu, Ryuta; Nuno Araujo, Nuno; Wurm, Gerhard; Herrmann, Hans

We investigate the electrostatic charging of an agitated bed of identical grains using simulations, mathematical modeling, and experiments. We simulate charging with a discrete-element model including electrical multipoles and find that infinitesimally small initial charges can grow exponentially rapidly. We propose a mathematical Turing model that defines conditions for exponential charging to occur and provides insights into the mechanisms involved. Finally, we confirm the predicted exponential growth in experiments using vibrated grains under microgravity, and we describe novel predicted spatiotemporal states that merit further study. I acknowledge support from NSF/DMR, award 1404792.

Large scale statistics for computational verification of grain growth simulations with experiments

International Nuclear Information System (INIS)

Demirel, Melik C.; Kuprat, Andrew P.; George, Denise C.; Straub, G.K.; Misra, Amit; Alexander, Kathleen B.; Rollett, Anthony D.

2002-01-01

It is known that by controlling microstructural development, desirable properties of materials can be achieved. The main objective of our research is to understand and control interface dominated material properties, and finally, to verify experimental results with computer simulations. We have previously showed a strong similarity between small-scale grain growth experiments and anisotropic three-dimensional simulations obtained from the Electron Backscattered Diffraction (EBSD) measurements. Using the same technique, we obtained 5170-grain data from an Aluminum-film (120 (micro)m thick) with a columnar grain structure. Experimentally obtained starting microstructure and grain boundary properties are input for the three-dimensional grain growth simulation. In the computational model, minimization of the interface energy is the driving force for the grain boundary motion. The computed evolved microstructure is compared with the final experimental microstructure, after annealing at 550 C. Characterization of the structures and properties of grain boundary networks (GBN) to produce desirable microstructures is one of the fundamental problems in interface science. There is an ongoing research for the development of new experimental and analytical techniques in order to obtain and synthesize information related to GBN. The grain boundary energy and mobility data were characterized by Electron Backscattered Diffraction (EBSD) technique and Atomic Force Microscopy (AFM) observations (i.e., for ceramic MgO and for the metal Al). Grain boundary energies are extracted from triple junction (TJ) geometry considering the local equilibrium condition at TJ's. Relative boundary mobilities were also extracted from TJ's through a statistical/multiscale analysis. Additionally, there are recent theoretical developments of grain boundary evolution in microstructures. In this paper, a new technique for three-dimensional grain growth simulations was used to simulate interface migration

Impact of energetic cosmic-ray ions on astrophysical ice grains

Energy Technology Data Exchange (ETDEWEB)

Mainitz, Martin; Anders, Christian; Urbassek, Herbert M., E-mail: urbassek@rhrk.uni-kl.de

2017-02-15

Highlights: • We use the REAX potential to model dissociations and reactions. • An ice grain consisting of a mixture of small molecules is considered. • The passage of a cosmic-ray ion initiates an ion track. • The track induces a shock wave and disintegrates the grain. • Abundant fragments and reaction products are detected. - Abstract: Using molecular-dynamics simulation with REAX potentials, we study the consequences of cosmic-ray ion impact on ice grains. The grains are composed of a mixture of H{sub 2}O, CO{sub 2}, NH{sub 3}, and CH{sub 3}OH molecules. Due to the high energy deposition of the cosmic-ray ion, 5 keV/nm, a strong pressure wave runs through the grain, while the interior of the ion track gasifies. Abundant molecular dissociations occur; reactions of the fragments form a variety of novel molecular product species.

Chevron defect at the intersection of grain boundaries with free surfaces in Au

International Nuclear Information System (INIS)

Radetic, T.; Lancon, F.; Dahmen, U.

2002-01-01

We have identified a new defect at the intersection between grain boundaries and surfaces in Au using atomic resolution transmission electron microscopy. At the junction line of 90 deg. tilt grain boundaries of (110)-(001) orientation with the free surface, a small segment of the grain boundary, about 1 nm in length, dissociates into a triangular region with a chevronlike stacking disorder and a distorted hcp structure. The structure and stability of these defects are confirmed by atomistic simulations, and we point out the relationship with the one-dimensional incommensurate structure of the grain boundary

Development, test and evaluation of a computerized procedure for using Landsat data to estimate spring small grains acreage

Science.gov (United States)

Mohler, R. R. J.; Palmer, W. F.; Smyrski, M. M.; Baker, T. C.; Nazare, C. V.

1982-01-01

A number of methods which can provide information concerning crop acreages on the basis of a utilization of multispectral scanner (MSS) data require for their implementation a comparatively large amount of labor. The present investigation is concerned with a project designed to improve the efficiency of analysis through increased automation. The Caesar technique was developed to realize this objective. The processability rates of the Caesar procedure versus the historical state-of-the-art proportion estimation procedures were determined in an experiment. Attention is given to the study site, the aggregation technology, the results of the aggregation test, and questions of error characterization. It is found that the Caesar procedure, which has been developed for the spring small grains region of North America, is highly efficient and provides accurate results.

Giant grains

International Nuclear Information System (INIS)

Leitch-Devlin, M.A.; Millar, T.J.; Williams, D.A.

1976-01-01

Infrared observations of the Orion nebula have been interpreted by Rowan-Robinson (1975) to imply the existence of 'giant' grains, radius approximately 10 -2 cm, throughout a volume about a parsec in diameter. Although Rowan-Robinson's model of the nebula has been criticized and the presence of such grains in Orion is disputed, the proposition is accepted, that they exist, and in this paper situations in which giant grains could arise are examined. It is found that, while a giant-grain component to the interstellar grain density may exist, it is difficult to understand how giant grains arise to the extent apparently required by the Orion nebula model. (Auth.)

76 FR 45397 - Export Inspection and Weighing Waiver for High Quality Specialty Grain Transported in Containers

Science.gov (United States)

2011-07-29

...-AB18 Export Inspection and Weighing Waiver for High Quality Specialty Grain Transported in Containers... permanent a waiver due to expire on July 31, 2012, for high quality specialty grain exported in containers... of high quality specialty grain exported in containers are small entities that up until recently...

To Everything There Is a Season: Summer-to-Winter Food Webs and the Functional Traits of Keystone Species.

Science.gov (United States)

Humphries, Murray M; Studd, Emily K; Menzies, Allyson K; Boutin, Stan

2017-11-01

From a trophic perspective, a seasonal increase in air temperature and photoperiod propagates as bottom-up pulse of primary production by plants, secondary production by herbivores, and tertiary production by carnivores. However, food web seasonality reflects not only abiotic variation in temperature and photoperiod, but also the composition of the biotic community and their functional responses to this variation. Some plants and animals-here referred to as seasonal specialists-decouple from food webs in winter through migration or various forms of metabolic arrest (e.g., senescence, diapause, and hibernation), whereas some plants and resident animals-here referred to as seasonal generalists-remain present and trophically coupled in winter. The co-occurrence of species with divergent responses to winter introduces seasonal variation in interaction strengths, resulting in summer-to-winter differences in trophic organization. Autumn cooling and shortening day length arrests primary productivity and cues seasonal herbivores to decouple, leaving generalist carnivores to concentrate their predation on the few generalist herbivores that remain resident, active, and vulnerable to predation in winter, which themselves feed on the few generalist plant structures available in winter. Thus, what was a bottom-up pulse, spread among many species in summer, including highly productive seasonal specialists, reverses into strong top-down regulation in winter that is top-heavy, and concentrated among a small number of generalist herbivores and their winter foods. Intermediate-sized, generalist herbivores that remain active and vulnerable to predation in winter are likely to be keystone species in seasonal food webs because they provide the essential ecosystem service of turning summer primary productivity into winter food for carnivores. Empirical examination of terrestrial mammals and their seasonal trophic status in the boreal forest and across an arctic-to-tropics seasonality

Temporal and Fine-Grained Pedestrian Action Recognition on Driving Recorder Database.

Science.gov (United States)

Kataoka, Hirokatsu; Satoh, Yutaka; Aoki, Yoshimitsu; Oikawa, Shoko; Matsui, Yasuhiro

2018-02-20

The paper presents an emerging issue of fine-grained pedestrian action recognition that induces an advanced pre-crush safety to estimate a pedestrian intention in advance. The fine-grained pedestrian actions include visually slight differences (e.g., walking straight and crossing), which are difficult to distinguish from each other. It is believed that the fine-grained action recognition induces a pedestrian intention estimation for a helpful advanced driver-assistance systems (ADAS). The following difficulties have been studied to achieve a fine-grained and accurate pedestrian action recognition: (i) In order to analyze the fine-grained motion of a pedestrian appearance in the vehicle-mounted drive recorder, a method to describe subtle change of motion characteristics occurring in a short time is necessary; (ii) even when the background moves greatly due to the driving of the vehicle, it is necessary to detect changes in subtle motion of the pedestrian; (iii) the collection of large-scale fine-grained actions is very difficult, and therefore a relatively small database should be focused. We find out how to learn an effective recognition model with only a small-scale database. Here, we have thoroughly evaluated several types of configurations to explore an effective approach in fine-grained pedestrian action recognition without a large-scale database. Moreover, two different datasets have been collected in order to raise the issue. Finally, our proposal attained 91.01% on National Traffic Science and Environment Laboratory database (NTSEL) and 53.23% on the near-miss driving recorder database (NDRDB). The paper has improved +8.28% and +6.53% from baseline two-stream fusion convnets.

Temporal and Fine-Grained Pedestrian Action Recognition on Driving Recorder Database

Directory of Open Access Journals (Sweden)

Hirokatsu Kataoka

2018-02-01

Full Text Available The paper presents an emerging issue of fine-grained pedestrian action recognition that induces an advanced pre-crush safety to estimate a pedestrian intention in advance. The fine-grained pedestrian actions include visually slight differences (e.g., walking straight and crossing, which are difficult to distinguish from each other. It is believed that the fine-grained action recognition induces a pedestrian intention estimation for a helpful advanced driver-assistance systems (ADAS. The following difficulties have been studied to achieve a fine-grained and accurate pedestrian action recognition: (i In order to analyze the fine-grained motion of a pedestrian appearance in the vehicle-mounted drive recorder, a method to describe subtle change of motion characteristics occurring in a short time is necessary; (ii even when the background moves greatly due to the driving of the vehicle, it is necessary to detect changes in subtle motion of the pedestrian; (iii the collection of large-scale fine-grained actions is very difficult, and therefore a relatively small database should be focused. We find out how to learn an effective recognition model with only a small-scale database. Here, we have thoroughly evaluated several types of configurations to explore an effective approach in fine-grained pedestrian action recognition without a large-scale database. Moreover, two different datasets have been collected in order to raise the issue. Finally, our proposal attained 91.01% on National Traffic Science and Environment Laboratory database (NTSEL and 53.23% on the near-miss driving recorder database (NDRDB. The paper has improved +8.28% and +6.53% from baseline two-stream fusion convnets.

Dissecting grain yield pathways and their interactions with grain dry matter content by a two-step correlation approach with maize seedling transcriptome

Directory of Open Access Journals (Sweden)

Melchinger Albrecht E

2010-04-01

Full Text Available Abstract Background The importance of maize for human and animal nutrition, but also as a source for bio-energy is rapidly increasing. Maize yield is a quantitative trait controlled by many genes with small effects, spread throughout the genome. The precise location of the genes and the identity of the gene networks underlying maize grain yield is unknown. The objective of our study was to contribute to the knowledge of these genes and gene networks by transcription profiling with microarrays. Results We assessed the grain yield and grain dry matter content (an indicator for early maturity of 98 maize hybrids in multi-environment field trials. The gene expression in seedlings of the parental inbred lines, which have four different genetic backgrounds, was assessed with genome-scale oligonucleotide arrays. We identified genes associated with grain yield and grain dry matter content using a newly developed two-step correlation approach and found overlapping gene networks for both traits. The underlying metabolic pathways and biological processes were elucidated. Genes involved in sucrose degradation and glycolysis, as well as genes involved in cell expansion and endocycle were found to be associated with grain yield. Conclusions Our results indicate that the capability of providing energy and substrates, as well as expanding the cell at the seedling stage, highly influences the grain yield of hybrids. Knowledge of these genes underlying grain yield in maize can contribute to the development of new high yielding varieties.

A QTL on the short arm of wheat (Triticum aestivum L.) chromosome 3B affects the stability of grain weight in plants exposed to a brief heat shock early in grain filling.

Science.gov (United States)

Shirdelmoghanloo, Hamid; Taylor, Julian D; Lohraseb, Iman; Rabie, Huwaida; Brien, Chris; Timmins, Andy; Martin, Peter; Mather, Diane E; Emebiri, Livinus; Collins, Nicholas C

2016-04-22

Molecular markers and knowledge of traits associated with heat tolerance are likely to provide breeders with a more efficient means of selecting wheat varieties able to maintain grain size after heat waves during early grain filling. A population of 144 doubled haploids derived from a cross between the Australian wheat varieties Drysdale and Waagan was mapped using the wheat Illumina iSelect 9,000 feature single nucleotide polymorphism marker array and used to detect quantitative trait loci for heat tolerance of final single grain weight and related traits. Plants were subjected to a 3 d heat treatment (37 °C/27 °C day/night) in a growth chamber at 10 d after anthesis and trait responses calculated by comparison to untreated control plants. A locus for single grain weight stability was detected on the short arm of chromosome 3B in both winter- and autumn-sown experiments, determining up to 2.5 mg difference in heat-induced single grain weight loss. In one of the experiments, a locus with a weaker effect on grain weight stability was detected on chromosome 6B. Among the traits measured, the rate of flag leaf chlorophyll loss over the course of the heat treatment and reduction in shoot weight due to heat were indicators of loci with significant grain weight tolerance effects, with alleles for grain weight stability also conferring stability of chlorophyll ('stay-green') and shoot weight. Chlorophyll loss during the treatment, requiring only two non-destructive readings to be taken, directly before and after a heat event, may prove convenient for identifying heat tolerant germplasm. These results were consistent with grain filling being limited by assimilate supply from the heat-damaged photosynthetic apparatus, or alternatively, accelerated maturation in the grains that was correlated with leaf senescence responses merely due to common genetic control of senescence responses in the two organs. There was no evidence for a role of mobilized stem reserves (water

Prevalence of operator fatigue in winter maintenance operations.

Science.gov (United States)

Camden, Matthew C; Medina-Flintsch, Alejandra; Hickman, Jeffrey S; Bryce, James; Flintsch, Gerardo; Hanowski, Richard J

2018-02-02

Similar to commercial motor vehicle drivers, winter maintenance operators are likely to be at an increased risk of becoming fatigued while driving due to long, inconsistent shifts, environmental stressors, and limited opportunities for sleep. Despite this risk, there is little research concerning the prevalence of winter maintenance operator fatigue during winter emergencies. The purpose of this research was to investigate the prevalence, sources, and countermeasures of fatigue in winter maintenance operations. Questionnaires from 1043 winter maintenance operators and 453 managers were received from 29 Clear Road member states. Results confirmed that fatigue was prevalent in winter maintenance operations. Over 70% of the operators and managers believed that fatigue has a moderate to significant impact on winter maintenance operations. Approximately 75% of winter maintenance operators reported to at least sometimes drive while fatigued, and 96% of managers believed their winter maintenance operators drove while fatigued at least some of the time. Furthermore, winter maintenance operators and managers identified fatigue countermeasures and sources of fatigue related to winter maintenance equipment. However, the countermeasures believed to be the most effective at reducing fatigue during winter emergencies (i.e., naps) were underutilized. For example, winter maintenance operators reported to never use naps to eliminate fatigue. These results indicated winter maintenance operations are impacted by operator fatigue. These results support the increased need for research and effective countermeasures targeting winter maintenance operator fatigue. Copyright © 2018 Elsevier Ltd. All rights reserved.

Electronic and atomic structures of KFe2Se2 grain boundaries

International Nuclear Information System (INIS)

Fan, Wei; Liu, Da-Yong; Zeng, Zhi

2014-01-01

Highlights: •Twist grain boundary has lower grain-boundary energy. •Twist grain-boundary has similar electronic structure to that in crystal. •Charge and magnetic-moment fluctuations are large within tilt grain boundary. •Bi-collinear AFM is most stable even with existence of grain boundary. •Insulating Fe-vacancy phase is stable with existence of twist grain boundary. -- Abstract: The electronic and atomic structures of the twist and tilt grain boundaries (GB) of the iron-based superconductor KFe 2 Se 2 are studied based on the simulations of the first principles density functional theory. Our results have clarified that the Σ5[0 0 1] twist grain boundary of KFe 2 Se 2 with layered structure has the lower grain-boundary energy. The local structure and the main features of the basic electronic structure within the [0 0 1] twist grain-boundary region have small differences compared with those in KFe 2 Se 2 crystal. The large fluctuations of the charges and magnetic moments are found in the [0 0 1] tilt grain-boundary regions, especially the former are more prominent. The bi-collinear anti-ferromagnetic order is the most stable magnetic order even with grain boundaries in the bulk. The √(5)a×√(5)a superstructure of Fe-vacancies in K 2 Fe 4 Se 5 phase is intrinsically related to the coincident-site lattice of Σ5[0 0 1] twist grain boundary

Carpel size, grain filling, and morphology determine individual grain weight in wheat.

Science.gov (United States)

Xie, Quan; Mayes, Sean; Sparkes, Debbie L

2015-11-01

Individual grain weight is a major yield component in wheat. To provide a comprehensive understanding of grain weight determination, the carpel size at anthesis, grain dry matter accumulation, grain water uptake and loss, grain morphological expansion, and final grain weight at different positions within spikelets were investigated in a recombinant inbred line mapping population of bread wheat (Triticum aestivum L.)×spelt (Triticum spelta L.). Carpel size, grain dry matter and water accumulation, and grain dimensions interacted strongly with each other. Furthermore, larger carpels, a faster grain filling rate, earlier and longer grain filling, more grain water, faster grain water absorption and loss rates, and larger grain dimensions were associated with higher grain weight. Frequent quantitative trait locus (QTL) coincidences between these traits were observed, particularly those on chromosomes 2A, 3B, 4A, 5A, 5DL, and 7B, each of which harboured 16-49 QTLs associated with >12 traits. Analysis of the allelic effects of coincident QTLs confirmed their physiological relationships, indicating that the complex but orderly grain filling processes result mainly from pleiotropy or the tight linkages of functionally related genes. After grain filling, distal grains within spikelets were smaller than basal grains, primarily due to later grain filling and a slower initial grain filling rate, followed by synchronous maturation among different grains. Distal grain weight was improved by increased assimilate availability from anthesis. These findings provide deeper insight into grain weight determination in wheat, and the high level of QTL coincidences allows simultaneous improvement of multiple grain filling traits in breeding. © The Author 2015. Published by Oxford University Press on behalf of the Society for Experimental Biology.

In situ grain fracture mechanics during uniaxial compaction of granular solids

Science.gov (United States)

Hurley, R. C.; Lind, J.; Pagan, D. C.; Akin, M. C.; Herbold, E. B.

2018-03-01

Grain fracture and crushing are known to influence the macroscopic mechanical behavior of granular materials and be influenced by factors such as grain composition, morphology, and microstructure. In this paper, we investigate grain fracture and crushing by combining synchrotron x-ray computed tomography and three-dimensional x-ray diffraction to study two granular samples undergoing uniaxial compaction. Our measurements provide details of grain kinematics, contacts, average intra-granular stresses, inter-particle forces, and intra-grain crystal and fracture plane orientations. Our analyses elucidate the complex nature of fracture and crushing, showing that: (1) the average stress states of grains prior to fracture vary widely in their relation to global and local trends; (2) fractured grains experience inter-particle forces and stored energies that are statistically higher than intact grains prior to fracture; (3) fracture plane orientations are primarily controlled by average intra-granular stress and contact fabric rather than the orientation of the crystal lattice; (4) the creation of new surfaces during fracture accounts for a very small portion of the energy dissipated during compaction; (5) mixing brittle and ductile grain materials alters the grain-scale fracture response. The results highlight an application of combined x-ray measurements for non-destructive in situ analysis of granular solids and provide details about grain fracture that have important implications for theory and modeling.

Canopy temperature depression at grain filling correlates to winter wheat yield in the U.S. southern high plains

Science.gov (United States)

Wheat breeding has improved drought tolerance over the years. However, our knowledge on drought tolerance in relation to the canopy temperature (CT) and grain yield is limited. A three-season wheat field study ending 2012, 2015, and 2016 was conducted at Bushland, Texas to investigate the relationsh...

Algorithm based on regional separation for automatic grain boundary extraction using improved mean shift method

Science.gov (United States)

Zhenying, Xu; Jiandong, Zhu; Qi, Zhang; Yamba, Philip

2018-06-01

Metallographic microscopy shows that the vast majority of metal materials are composed of many small grains; the grain size of a metal is important for determining the tensile strength, toughness, plasticity, and other mechanical properties. In order to quantitatively evaluate grain size in metals, grain boundaries must be identified in metallographic images. Based on the phenomenon of grain boundary blurring or disconnection in metallographic images, this study develops an algorithm based on regional separation for automatically extracting grain boundaries by an improved mean shift method. Experimental observation shows that the grain boundaries obtained by the proposed algorithm are highly complete and accurate. This research has practical value because the proposed algorithm is suitable for grain boundary extraction from most metallographic images.

Extreme winter warming events more negatively impact small rather than large soil fauna: shift in community composition explained by traits not taxa.

NARCIS (Netherlands)

Bokhorst, S.F.; Phoenix, G.K.; Bjerke, J.W.; Callaghan, T.V.; Huyer-Brugman, F.A.; Berg, M.P.

2012-01-01

Extreme weather events can have negative impacts on species survival and community structure when surpassing lethal thresholds. Extreme winter warming events in the Arctic rapidly melt snow and expose ecosystems to unseasonably warm air (2-10 °C for 2-14 days), but returning to cold winter climate

Cycling of grain legume residue nitrogen

DEFF Research Database (Denmark)

Jensen, E.S.

1995-01-01

Symbiotic nitrogen fixation by legumes is the main input of nitrogen in ecological agriculture. The cycling of N-15-labelled mature pea (Pisum sativum L.) residues was studied during three years in small field plots and lysimeters. The residual organic labelled N declined rapidly during the initial...... management methods in order to conserve grain legume residue N sources within the soil-plant system....

Change of Landscape Structure before and after Winter Olympic Games in Nagano City

Science.gov (United States)

Fujii, Yoshio; Takeda, Toshiharu

Recently it is desirable to realize the conservation of biodiversity and to create the city with symbiosis with nature even in local city. In this study, we chose Nagano City which was the site of the Winter Olympic Games as the subject of study, investigated the change of land cover by using Landsat TM data of the year 1985 and 1999 which were before and after the Winter Olympic Games, and grasped the change of landscape structure quantitatively by using landscape indices. As a result, we obtained the following conclusions. The expansion of urban area proceeded rapidly before and after the Winter Olympic Games. The area of artificial land cover in the city planning area has increased by 57%. In the meantime the areas of upland field and paddy field have decreased by 45% and 50% respectively. Therefore, agricultural land changed into urban area remarkably. It was found that the shape of paches of paddy field and upland field especially became small and the inequality of the paches decreased before and after the Winter Olympic Games. It became clear that the fragmentation has occurred in agricultural land such as paddy field, upland field and orchard.

Grain yields and disease resistance as selection criteria for introduction of new varieties of small grain cereal in Lubumbashi, D.R. Congo.

Science.gov (United States)

Mukobo, M R P; Ngongo, L M; Haesaert, G

2014-01-01

Wheat production in African countries is a major challenge for their development, considering their increasing consumption of wheat flour products. In the Democratic Republic of Congo, wheat and wheat-based products are the important imported food products although there is a potential for the cultivation of small grain cereals such as durum wheat, wheat and triticale. Trials done in Lubumbashi in the Katanga Province have shown that Septoria Leaf Blotch, Septoria Glume Blotch and Fusarium head blight are the main constraints to the efficient development of these cultures. Some varieties of Elite Spring Wheat, High Rainfall Wheat, Triticale and Durum Wheat from CIMMYT were followed during 4 growing seasons and agronomic characteristics and their levels of disease resistance were recorded. Correlations of agronomic characteristics with yields showed that in most cases, thousand kernel weight is the parameter that has the most influence on the yield level (p < 0.0001). The analysis of variance for all diseases showed that there were significant effects related to the year, the species and the interaction years x species. Triticale varieties seem to have a better resistance against the two forms of Septoria compared to wheat varieties but, they seem to be more sensitive to Fusarium Head Blight than wheat varieties. However, the Fusarium Head Blight has a rather low incidence in Lubumbashi.

Early sowing increases nitrogen uptake and yields of winter wheat grown with cattle slurry or mineral fertilizers

DEFF Research Database (Denmark)

Suarez, Alfonso; Rasmussen, Jim; Thomsen, Ingrid Kaag

2018-01-01

of the two cultivars did not differ consistently with respect to the effect of early sowing on crop yield, N concentration and offtake, or ANR. Within the north-west European climatic region, moving the sowing time of winter wheat from mid-September to mid-August provides a significant yield and N offtake......The current study evaluated the effect of sowing date (early, mid-August or timely, mid-September) on two winter wheat (Triticum aestivum L.) cultivars (Hereford, Mariboss) with different rates of nitrogen (N) (0–225 kg total N/ha) applied as animal manure (AM; cattle slurry) or mineral fertilizers...... (N: phosphorus: potassium; NPK). Overwinter plant N uptake and soil mineral N content were determined during 2014/15, while harvest yields (grain, straw, N content) were determined during 2014/15 and 2015/16. Overwinter uptake of N was 14 kg N/ha higher in early than in timely-sown wheat. Despite...

Transport properties of olivine grain boundaries from electrical conductivity experiments

Science.gov (United States)

Pommier, Anne; Kohlstedt, David L.; Hansen, Lars N.; Mackwell, Stephen; Tasaka, Miki; Heidelbach, Florian; Leinenweber, Kurt

2018-05-01

Grain boundary processes contribute significantly to electronic and ionic transports in materials within Earth's interior. We report a novel experimental study of grain boundary conductivity in highly strained olivine aggregates that demonstrates the importance of misorientation angle between adjacent grains on aggregate transport properties. We performed electrical conductivity measurements of melt-free polycrystalline olivine (Fo90) samples that had been previously deformed at 1200 °C and 0.3 GPa to shear strains up to γ = 7.3. The electrical conductivity and anisotropy were measured at 2.8 GPa over the temperature range 700-1400 °C. We observed that (1) the electrical conductivity of samples with a small grain size (3-6 µm) and strong crystallographic preferred orientation produced by dynamic recrystallization during large-strain shear deformation is a factor of 10 or more larger than that measured on coarse-grained samples, (2) the sample deformed to the highest strain is the most conductive even though it does not have the smallest grain size, and (3) conductivity is up to a factor of 4 larger in the direction of shear than normal to the shear plane. Based on these results combined with electrical conductivity data for coarse-grained, polycrystalline olivine and for single crystals, we propose that the electrical conductivity of our fine-grained samples is dominated by grain boundary paths. In addition, the electrical anisotropy results from preferential alignment of higher-conductivity grain boundaries associated with the development of a strong crystallographic preferred orientation of the grains.

The U.S. Federal Highway Administration winter Maintenance Decision Support System (MDSS) project

Energy Technology Data Exchange (ETDEWEB)

Pisano, P.A. [Federal Highway Administration, Road Weather Managment Program, Washington, D.C. (United States); Stern, A.D. [Mitretek Systems, Inc., Oceanic, Atmospheric and Space Systems, Falls Church, VA (United States); Mahoney, W.P. [National Center for Atmospheric Research, Research Applications Program, Boulder, CO (United States)

2004-07-01

Managing a winter maintenance program today is an increasingly complex endeavor. Just making sure that a plow blade is at the ready when the first flake falls is only a small part of the task. With tight budgets and the high expectation of the public for keeping roads clear of snow and ice, today's maintenance manager has to be able to handle multiple tasks or risk getting behind the onslaught of winter weather. Good information leads to effective practices, however all of the regulations concerning chemical applications, environmental impacts and multiple, often contradictory weather forecasts can lead to information overload. The United States Department of Transportation (DOT), Federal Highway Administration (FHWA) recognized this potential problem in the late 1990's as part of its Road Weather Management (RWM) program. Generally speaking, there were plenty of weather forecasts, along with a few companies that issued road-specific forecasts, but there was a lack of linkage between the information available and the decisions made by winter maintenance managers. It was this weak link that became the genesis for the winter Maintenance Decision Support System (MDSS). The MDSS has since matured into a functional prototype. During the winter of 2002-2003, the prototype was deployed at several maintenance garages in central Iowa for a field demonstration. This paper will document the implementation of the demonstration, a summary of lessons learned, and technology transfer activities. It will also describe plans for a longer, more comprehensive demonstration during the winter of 2003-2004. (orig.)

Martini Coarse-Grained Force Field : Extension to Carbohydrates

NARCIS (Netherlands)

Lopez, Cesar A.; Rzepiela, Andrzej J.; de Vries, Alex H.; Dijkhuizen, Lubbert; Huenenberger, Philippe H.; Marrink, Siewert J.

2009-01-01

We present an extension of the Martini coarse-grained force field to carbohydrates. The parametrization follows the same philosophy as was used previously for lipids and proteins, focusing on the reproduction of partitioning free energies of small compounds between polar and nonpolar phases. The

Prevalence of IgE antibodies to grain and grain dust in grain elevator workers.

Science.gov (United States)

Lewis, D M; Romeo, P A; Olenchock, S A

1986-01-01

IgE-mediated allergic reactions have been postulated to contribute to respiratory reactions seen in workers exposed to grain dusts. In an attempt better to define the prevalence of IgE antibodies in workers exposed to grain dusts, we performed the radioallergosorbent test (RAST) on worker sera using both commercial allergens prepared from grain and worksite allergens prepared from grain dust samples collected at the worksite. We found that the two types of reagents identified different populations with respect to the specificity of IgE antibodies present. The RAST assay performed using worksite allergens correlated well with skin test procedures. These results may allow us to gain better understanding of allergy associated with grain dust exposure, and document the utility of the RAST assay in assessment of occupational allergies. PMID:3709478

Prevalence of IgE antibodies to grain and grain dust in grain elevator workers

Energy Technology Data Exchange (ETDEWEB)

Lewis, D.M.; Romeo, P.A.; Olenchock, S.A.

1986-04-01

IgE-mediated allergic reactions have been postulated to contribute to respiratory reactions seen in workers exposed to grain dusts. In an attempt better to define the prevalence of IgE antibodies in workers exposed to grain dusts, we performed the radioallergosorbent test (RAST) on worker sera using both commercial allergens prepared from grain and worksite allergens prepared from grain dust samples collected at the worksite. We found that the two types of reagents identified different populations with respect to the specificity of IgE antibodies present. The RAST assay performed using worksite allergens correlated well with skin test procedures. These results may allow us to gain better understanding of allergy associated with grain dust exposure, and document the utility of the RAST assay in assessment of occupational allergies.

Prevalence of IgE antibodies to grain and grain dust in grain elevator workers

International Nuclear Information System (INIS)

Lewis, D.M.; Romeo, P.A.; Olenchock, S.A.

1986-01-01

IgE-mediated allergic reactions have been postulated to contribute to respiratory reactions seen in workers exposed to grain dusts. In an attempt better to define the prevalence of IgE antibodies in workers exposed to grain dusts, we performed the radioallergosorbent test (RAST) on worker sera using both commercial allergens prepared from grain and worksite allergens prepared from grain dust samples collected at the worksite. We found that the two types of reagents identified different populations with respect to the specificity of IgE antibodies present. The RAST assay performed using worksite allergens correlated well with skin test procedures. These results may allow us to gain better understanding of allergy associated with grain dust exposure, and document the utility of the RAST assay in assessment of occupational allergies

Climate impact of idealized winter polar mesospheric and stratospheric ozone losses as caused by energetic particle precipitation

Science.gov (United States)

Meraner, Katharina; Schmidt, Hauke

2018-01-01

Energetic particles enter the polar atmosphere and enhance the production of nitrogen oxides and hydrogen oxides in the winter stratosphere and mesosphere. Both components are powerful ozone destroyers. Recently, it has been inferred from observations that the direct effect of energetic particle precipitation (EPP) causes significant long-term mesospheric ozone variability. Satellites observe a decrease in mesospheric ozone up to 34 % between EPP maximum and EPP minimum. Stratospheric ozone decreases due to the indirect effect of EPP by about 10-15 % observed by satellite instruments. Here, we analyze the climate impact of winter boreal idealized polar mesospheric and polar stratospheric ozone losses as caused by EPP in the coupled Max Planck Institute Earth System Model (MPI-ESM). Using radiative transfer modeling, we find that the radiative forcing of mesospheric ozone loss during polar night is small. Hence, climate effects of mesospheric ozone loss due to energetic particles seem unlikely. Stratospheric ozone loss due to energetic particles warms the winter polar stratosphere and subsequently weakens the polar vortex. However, those changes are small, and few statistically significant changes in surface climate are found.

Eco-functional intensification by cereal-grain legume intercropping in organic farming systems for increased yields, reduced weeds and improved grain protein concentration

DEFF Research Database (Denmark)

Bedoussac, Laurent; Journet, Étienne-Pascal; Hauggaard-Nielsen, Henrik

2014-01-01

Intercropping, i.e., simultaneously growing two (or more) species in the same field for a significant period of time but without necessarily concomitant sowing or harvest, is a practice aimed at eco-functional intensification. This chapter integrates a comprehensive amount of original data from...... field experiments conducted since 2001 on spring and winter cereal-grain legume intercrops in experimental and farm contexts in France and Denmark, in an attempt to generalise the findings and draw up common guidelines. We have shown that intercrops appear to be a useful agronomic solution for organic......, structure and manuring strategies. Consequently, it should be emphasized that: (i) the species and varietal traits suited to intercropping and organic farming will make it necessary to reconsider the varietal selection criteria; (ii) further mechanistic understanding of the behaviour of intercropping...

The influence of tungsten powder grain size on the properties of small bars and thick wires

International Nuclear Information System (INIS)

Jesionek, B.; Ludynski, Z.

1980-01-01

The object of the investigations was, if possible, to determine the exact significance of the influence of the pressing parameters on the properties of tungsten bars and larger diameter wires, with special reference to the size of the tungsten grains. Tungsten powders, reduced under different conditions and with different grain sizes, were used for the investigations. These powders were pressed in steel dies at three different pressures, 72.5, 108, and 176 MPa, and the pressings were sintered. After sintering, the following properties of the bars were examined: ability to sinter, strength, and grain size. The bars were then worked down to 1.02 mm diameter wire and the following properties measured: tensile strength, plastic properties and the occurence of internal flaws (cracks). Finally, the optimum pressing parameters of the tungsten powder were determined. (Auth.)

46 CFR 45.73 - Winter freeboard.

Science.gov (United States)

2010-10-01

... 46 Shipping 2 2010-10-01 2010-10-01 false Winter freeboard. 45.73 Section 45.73 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) LOAD LINES GREAT LAKES LOAD LINES Freeboards § 45.73 Winter freeboard. The minimum winter freeboard (fw) in inches is obtained by the formula: fw=f(s)+T s...

Grain-size effect on the electrical properties of nanocrystalline indium tin oxide thin films

Energy Technology Data Exchange (ETDEWEB)

Lee, Jong Hoon [Korea Research Institute of Standards and Science, 267 Gajeong-Ro, Yuseong-Gu, Daejeon 305-340 (Korea, Republic of); Kim, Young Heon, E-mail: young.h.kim@kriss.re.kr [Korea Research Institute of Standards and Science, 267 Gajeong-Ro, Yuseong-Gu, Daejeon 305-340 (Korea, Republic of); University of Science & Technology, 217 Gajeong-Ro, Yuseong-Gu, Daejeon 305-350 (Korea, Republic of); Ahn, Sang Jung [Korea Research Institute of Standards and Science, 267 Gajeong-Ro, Yuseong-Gu, Daejeon 305-340 (Korea, Republic of); University of Science & Technology, 217 Gajeong-Ro, Yuseong-Gu, Daejeon 305-350 (Korea, Republic of); Ha, Tae Hwan [University of Science & Technology, 217 Gajeong-Ro, Yuseong-Gu, Daejeon 305-350 (Korea, Republic of); Future Biotechnology Research Division, Korea Research Institute of Bioscience and Biotechnology (KRIBB), 125 Gwahak-ro, Yuseong-Gu, Daejeon 305-806 (Korea, Republic of); Kim, Hong Seung [Department of Nano Semiconductor Engineering, Korea Maritime and Ocean University, 727 Taejong-Ro, Busan 606-791 (Korea, Republic of)

2015-09-15

Highlights: • Nanometer-sized small grains were observed in the ITO thin films. • The grain size increased as the post-thermal annealing temperature increased. • The mobility of ITO thin films increased with increasing grain size. • The ITO film annealed at 300 °C was an amorphous phase, while the others were polycrystalline structure. - Abstract: In this paper, we demonstrate the electrical properties, depending on grain size, of nanocrystalline indium tin oxide (ITO) thin films prepared with a solution process. The size distributions of nanometer-sized ITO film grains increased as the post-annealing temperature increased after deposition; the grain sizes were comparable with the calculated electron mean free path. The mobility of ITO thin films increased with increasing grain size; this phenomenon was explained by adopting the charge-trapping model for grain boundary scattering. These findings suggest that it is possible to improve mobility by reducing the number of trapping sites at the grain boundary.

Modelling fungal sink competitiveness with grains for assimilates in wheat infected by a biotrophic pathogen

Science.gov (United States)

Bancal, Marie-Odile; Hansart, Amandine; Sache, Ivan; Bancal, Pierre

2012-01-01

Background and Aims Experiments have shown that biotrophic fungi divert assimilates for their growth. However, no attempt has been made either to account for this additional sink or to predict to what extent it competes with both grain filling and plant reserve metabolism for carbon. Fungal sink competitiveness with grains was quantified by a mixed experimental–modelling approach based on winter wheat infected by Puccinia triticina. Methods One week after anthesis, plants grown under controlled conditions were inoculated with varying loads. Sporulation was recorded while plants underwent varying degrees of shading, ensuring a range of both fungal sink and host source levels. Inoculation load significantly increased both sporulating area and rate. Shading significantly affected net assimilation, reserve mobilization and sporulating area, but not grain filling or sporulation rates. An existing carbon partitioning (source–sink) model for wheat during the grain filling period was then enhanced, in which two parameters characterize every sink: carriage capacity and substrate affinity. Fungal sink competitiveness with host sources and sinks was modelled by representing spore production as another sink in diseased wheat during grain filling. Key Results Data from the experiment were fitted to the model to provide the fungal sink parameters. Fungal carriage capacity was 0·56 ± 0·01 µg dry matter °Cd−1 per lesion, much less than grain filling capacity, even in highly infected plants; however, fungal sporulation had a competitive priority for assimilates over grain filling. Simulation with virtual crops accounted for the importance of the relative contribution of photosynthesis loss, anticipated reserve depletion and spore production when light level and disease severity vary. The grain filling rate was less reduced than photosynthesis; however, over the long term, yield loss could double because the earlier reserve depletion observed here would shorten the

Winter sowing of adapted lines as a potential yield increase strategy in lentil (Lens culinaris Medik.)

Energy Technology Data Exchange (ETDEWEB)

Barrios, A.; Aparicio, T.; Rodríguez, M.J.; Pérez de la Vega, M.; Caminero, C.

2016-11-01

Lentil (Lens culinaris Medik. subsp. culinaris) is a traditional crop in Spain although current grain yield in Spain is relatively low and unstable. The effect of an early sowing date (winter sowing) on yield in the Spanish Central Plateau (meseta) was analyzed comparing it to the traditional spring sowing. Yield from eleven cultivars currently available for sowing in Spain and two F6:7 populations of recombinant inbred lines (RIL), ´Precoz´ × ´WA8649041´ (89 lines) and ´BGE016365´ × ´ILL1918´ (118 lines), was evaluated in winter and spring sowing dates for three seasons (2005/06, 2006/07 and 2007/08) and two localities. Yield and stability were assessed by the method of consistency of performance with some modifications. When comparing with the best currently available cultivars sown in the traditional spring sowing date, (with an estimated average yield of 43.9 g/m in our experimental conditions), winter sowing using adapted breeding lines proved to be a suitable strategy for increasing lentil yield and yield stability in the Spanish meseta, with an average yield increase of 111% (reaching an estimated yield of 92.8 g/m). Results point to that lentil production can greatly increase in the Spanish meseta if adequate plant materials, such as some of the lines analyzed, are sown at late fall. (Author)

Winter sowing of adapted lines as a potential yield increase strategy in lentil (Lens culinaris Medik.

Directory of Open Access Journals (Sweden)

Abel Barrios

2016-06-01

Full Text Available Lentil (Lens culinaris Medik. subsp. culinaris is a traditional crop in Spain although current grain yield in Spain is relatively low and unstable. The effect of an early sowing date (winter sowing on yield in the Spanish Central Plateau (meseta was analyzed comparing it to the traditional spring sowing. Yield from eleven cultivars currently available for sowing in Spain and two F6:7  populations of recombinant inbred lines (RIL, ´Precoz´ × ´WA8649041´ (89 lines and ´BGE016365´ × ´ILL1918´ (118 lines, was evaluated in winter and spring sowing dates for three seasons (2005/06, 2006/07 and 2007/08 and two localities. Yield and stability were assessed by the method of consistency of performance with some modifications. When comparing with the best currently available cultivars sown in the traditional spring sowing date, (with an estimated average yield of 43.9 g/m in our experimental conditions, winter sowing using adapted breeding lines proved to be a suitable strategy for increasing lentil yield and yield stability in the Spanish meseta, with an average yield increase of 111% (reaching an estimated yield of 92.8 g/m. Results point to that lentil production can greatly increase in the Spanish meseta if adequate plant materials, such as some of the lines analyzed, are sown at late fall.

Electrostatic Charging and Particle Interactions in Microscopic Insulating Grains

Science.gov (United States)

Lee, Victor

In this thesis, we experimentally investigate the electrostatic charging as well as the particle interactions in microscopic insulating grains. First, by tracking individual grains accelerated in an electric field, we quantitatively demonstrate that tribocharging of same-material grains depends on particle size. Large grains tend to charge positively, and small ones tend to charge negatively. Theories based on the transfer of trapped electrons can explain this tendency but have not been validated. Here we show that the number of trapped electrons, measured independently by a thermoluminescence technique, is orders of magnitude too small to be responsible for the amount of charge transferred. This result reveals that trapped electrons are not responsible for same-material tribocharging of dielectric particles. Second, same-material tribocharging in grains can result in important long-range electrostatic interactions. However, how these electrostatic interactions contribute to particle clustering remains elusive, primarily due to the lack of direct, detailed observations. Using a high-speed camera that falls with a stream charged grains, we observe for the first time how charged grains can undergo attractive as well as repulsive Kepler-like orbits. Charged particles can be captured in their mutual electrostatic potential and form clusters via multiple bounces. Dielectric polarization effects are directly observed, which lead to additional attractive forces and stabilize "molecule-like" arrangements of charged particles. Third, we have developed a new method to study the charge transfer of microscopic particles based on acoustic levitation techniques. This method allows us to narrow the complex problem of many-particle charging down to precise charge measurements of a single sub-millimeter particle colliding with a target plate. By simply attaching nonpolar groups onto glass surfaces, we show that the contact charging of a particle is highly dependent on

'Downward control' of the mean meridional circulation and temperature distribution of the polar winter stratosphere

Science.gov (United States)

Garcia, Rolando R.; Boville, Byron A.

1994-01-01

According to the 'downward control' principle, the extratropical mean vertical velocity on a given pressure level is approximately proportional to the meridional gradient of the vertically integrated zonal force per unit mass exerted by waves above that level. In this paper, a simple numerical model that includes parameterizations of both planetary and gravity wave breaking is used to explore the influence of gravity wave breaking in the mesosphere on the mean meridional circulation and temperature distribution at lower levels in the polar winter stratosphere. The results of these calculations suggest that gravity wave drag in the mesosphere can affect the state of the polar winter stratosphere down to altitudes below 30 km. The effect is most important when planetary wave driving is relatively weak: that is, during southern winter and in early northern winter. In southern winter, downwelling weakens by a factor of 2 near the stratospause and by 20% at 30 km when gravity wave drag is not included in the calculations. As a consequence, temperatures decrease considerably throughout the polar winter stratosphere (over 20 K above 40 km and as much as 8 K at 30 km, where the effect is enhanced by the long radiative relaxation timescale). The polar winter states obtained when gravity wave drag is omitted in this simple model resemble the results of simulations with some general circulation models and suggest that some of the shortcomings of the latter may be due to a deficit in mesospheric momentum deposition by small-scale gravity waves.

Thermomagnetic Stability in Pseudo Single Domain Grains

Science.gov (United States)

Nagy, Lesleis; Williams, Wyn; Muxworthy, Adrian; Fabian, Karl; Conbhuí, Pádraig Ó.

2016-04-01

The reliability of paleomagnetic remanences are well understood for fine grains of magnetite that are single-domain (SD, uniformly magnetized). In particular Néel's theory [1] outlined the thermal energies required to block and unblock magnetic remanences. This lead to determination of thermal stability for magnetization in fine grains as outlined in Pullaiah et. al. [2] and a comprehensive understanding of SD paleomagnetic recordings. It has been known for some time that single domain magnetite is possible only in the grain size range 30 - 80nm, which may only account for a small fraction of the grain size distribution in any rock sample. Indeed rocks are often dominated by grains in the pseudo single domain (PSD) size range, at approximately 80 - 1000nm. Toward the top end of this range multi-domain features begin to dominate. In order to determine thermomagnetic stability in PSD grains we need to identify the energy barriers between all possible pairs of local energy minima (LEM) domain states as a function of both temperature and grain size. We have attempted to do this using the nudged elastic band (NEB) method [3] which searches for minimum energy paths between any given pair of LEM states. Using this technique we have determined, for the first time, complete thermomagnetic stability curves for PSD magnetite. The work presented is at a preliminary stage. However it can be shown that PSD grains of magnetite with simple geometries (e.g. cubes or cuboctahedra) have very few low energy transition paths and the stability is likely to be similar to that observed for SD grains (as expected form experimental observations). The results will provide a basis for a much more rigorous understanding of the fidelity of paleomagnetic signals in assemblages of PSD grains and their ability to retain ancient recordings of the geomagnetic field. References: [1] Néel, Louis. "Théorie du traînage magnétique des ferromagnétiques en grains fins avec applications aux terres

A three-component system incorporating Ppd-D1, copy number variation at Ppd-B1, and numerous small-effect quantitative trait loci facilitates adaptation of heading time in winter wheat cultivars of worldwide origin.

Science.gov (United States)

Würschum, Tobias; Langer, Simon M; Longin, C Friedrich H; Tucker, Matthew R; Leiser, Willmar L

2018-06-01

The broad adaptability of heading time has contributed to the global success of wheat in a diverse array of climatic conditions. Here, we investigated the genetic architecture underlying heading time in a large panel of 1,110 winter wheat cultivars of worldwide origin. Genome-wide association mapping, in combination with the analysis of major phenology loci, revealed a three-component system that facilitates the adaptation of heading time in winter wheat. The photoperiod sensitivity locus Ppd-D1 was found to account for almost half of the genotypic variance in this panel and can advance or delay heading by many days. In addition, copy number variation at Ppd-B1 was the second most important source of variation in heading, explaining 8.3% of the genotypic variance. Results from association mapping and genomic prediction indicated that the remaining variation is attributed to numerous small-effect quantitative trait loci that facilitate fine-tuning of heading to the local climatic conditions. Collectively, our results underpin the importance of the two Ppd-1 loci for the adaptation of heading time in winter wheat and illustrate how the three components have been exploited for wheat breeding globally. © 2018 John Wiley & Sons Ltd.

A grain-boundary diffusion model of dynamic grain growth during superplastic deformation

International Nuclear Information System (INIS)

Kim, Byung-Nam; Hiraga, Keijiro; Sakka, Yoshio; Ahn, Byung-Wook

1999-01-01

Dynamic grain growth during superplastic deformation is modelled on the basis of a grain-boundary diffusion mechanism. On the grain boundary where a static and a dynamic potential difference coexist, matter transport along the boundary is assumed to contribute to dynamic grain growth through depositing the matter on the grain surface located opposite to the direction of grain-boundary migration. The amount of the diffusive matter during deformation is calculated for an aggregate of spherical grains and is converted to the increment of mean boundary migration velocity. The obtained relationship between the strain rate and the dynamic grain growth rate is shown to be independent of deformation mechanisms, provided that the grain growth is controlled by grain-boundary diffusion. The strain dependence, strain-rate dependence and temperature dependence of grain growth predicted from this model are consistent with those observed in superplastic ZrO 2 -dispersed Al 2 O 3

Grain-boundary effects on the magnetoresistance properties of perovskite manganite films

International Nuclear Information System (INIS)

Gupta, A.; Gong, G.Q.; Xiao, G.; Duncombe, P.R.; Lecoeur, P.; Trouilloud, P.; Wang, Y.Y.; Dravid, V.P.; Sun, J.Z.

1996-01-01

The role of grain boundaries in the magnetoresistance (MR) properties of the manganites has been investigated by comparing the properties of epitaxial and polycrystalline films of La 0.67 D 0.33 MnO 3-δ (D=Ca,Sr, or vacancies). While the MR in the epitaxial films is strongly peaked near the ferromagnetic transition temperature and is very small at low temperatures, the polycrystalline films show large MR over a wide temperature range down to 5 K. The results are explained in terms of switching of magnetic domains in the grains and disorder-induced canting of Mn spins in the grain-boundary region. copyright 1996 The American Physical Society

Russian Kefir Grains Microbial Composition and Its Changes during Production Process.

Science.gov (United States)

Kotova, I B; Cherdyntseva, T A; Netrusov, A I

2016-01-01

By combining DGGE-PCR method, classical microbiological analysis and light- and electron microscopic observations, it was found that the composition of microbial communities of central Russia regions kefir grains, starter and kefir drink include bacteria of the genera Lactobacillus, Leuconostoc and Lactococcus, and yeast anamorphs of the genera Saccharomyces, Kazachstania and Gibellulopsis. Fifteen prokaryotic and four eukaryotic pure cultures of microorganisms were isolated and identified from kefir grains. It has been shown that members of the genus Lactobacillus prevailed in kefir grains, whereas strains Leuconostoc pseudomesenteroides and Lactococcus lactis dominated in the final product - kefir drink. Yeasts contained in kefir grains in small amounts have reached a significant number of cells in the process of development of this dairy product. The possibility of reverse cell aggregation has been attempted in a mixed cultivation of all isolated pure cultures, but full formation kefir grains is not yet observed after 1.5 years of observation and reinoculations.

Carpel size, grain filling, and morphology determine individual grain weight in wheat

OpenAIRE

Xie, Quan; Mayes, Sean; Sparkes, Debbie L.

2015-01-01

Individual grain weight is a major yield component in wheat. To provide a comprehensive understanding of grain weight determination, the carpel size at anthesis, grain dry matter accumulation, grain water uptake and loss, grain morphological expansion, and final grain weight at different positions within spikelets were investigated in a recombinant inbred line mapping population of bread wheat (Triticum aestivum L.)?spelt (Triticum spelta L.). Carpel size, grain dry matter and water accumulat...

Complex Role of Secondary Electron Emissions in Dust Grain Charging in Space Environments: Measurements on Apollo 11 and 17 Dust Grains

Science.gov (United States)

Abbas, M. M.; Tankosic, D.; Spann, J. F.; LeClair, A. C.

2010-01-01

Dust grains in various astrophysical environments are generally charged electrostatically by photoelectric emissions with radiation from nearby sources, or by electron/ion collisions by sticking or secondary electron emissions. Knowledge of the dust grain charges and equilibrium potentials is important for understanding of a variety of physical and dynamical processes in the interstellar medium (ISM), and heliospheric, interplanetary, planetary, and lunar environments. The high vacuum environment on the lunar surface leads to some unusual physical and dynamical phenomena involving dust grains with high adhesive characteristics, and levitation and transportation over long distances. It has been well recognized that the charging properties of individual micron/submicron size dust grains are expected to be substantially different from the corresponding values for bulk materials and theoretical models. In this paper we present experimental results on charging of individual dust grains selected from Apollo 11 and Apollo 17 dust samples by exposing them to mono-energetic electron beams in the 10- 400 eV energy range. The charging rates of positively and negatively charged particles of approximately 0.2 to 13 microns diameters are discussed in terms of the secondary electron emission (SEE) process, which is found to be a complex charging process at electron energies as low as 10-25 eV, with strong particle size dependence. The measurements indicate substantial differences between dust charging properties of individual small size dust grains and of bulk materials.

Diffusion coefficients of Fokker-Planck equation for rotating dust grains in a fusion plasma

Science.gov (United States)

Bakhtiyari-Ramezani, M.; Mahmoodi, J.; Alinejad, N.

2015-11-01

In the fusion devices, ions, H atoms, and H2 molecules collide with dust grains and exert stochastic torques which lead to small variations in angular momentum of the grain. By considering adsorption of the colliding particles, thermal desorption of H atoms and normal H2 molecules, and desorption of the recombined H2 molecules from the surface of an oblate spheroidal grain, we obtain diffusion coefficients of the Fokker-Planck equation for the distribution function of fluctuating angular momentum. Torque coefficients corresponding to the recombination mechanism show that the nonspherical dust grains may rotate with a suprathermal angular velocity.

Winter warming from large volcanic eruptions

Science.gov (United States)

Robock, Alan; Mao, Jianping

1992-01-01

An examination of the Northern Hemisphere winter surface temperature patterns after the 12 largest volcanic eruptions from 1883-1992 shows warming over Eurasia and North America and cooling over the Middle East which are significant at the 95-percent level. This pattern is found in the first winter after tropical eruptions, in the first or second winter after midlatitude eruptions, and in the second winter after high latitude eruptions. The effects are independent of the hemisphere of the volcanoes. An enhanced zonal wind driven by heating of the tropical stratosphere by the volcanic aerosols is responsible for the regions of warming, while the cooling is caused by blocking of incoming sunlight.

Variation in the Level of Grain Defect Light Flecks and Spots on Cattle Hides

Science.gov (United States)

Nafstad, O; Grønstøl, H

2001-01-01

The occurrence of hide damage light flecks and spots was determined on tanned hides from 28 herds during a period of 8 to 12 months. Light flecks and spots are described as small areas of grain loss up to 3 mm in diameter that are seen on dyed crust cattle leather. Damage was found on 75.8% of all hides. The neck and shoulders were the anatomical region with the highest prevalence of damage. Sixty-eight per cent of all hides had light flecks and spots in this region. The forelimbs and dewlap were the anatomical region with the second highest occurrence with a prevalence of 39.1%. This distribution corresponded to the known distribution of lice in cattle. No significant differences were observed in age, sex, prevalence of lice in the herd assessed in March or infestations with different lice species. The frequency of light flecks and spots varied significantly during the year. The frequency was highest in the late winter and early spring, decreased significantly during the summer and was lowest in the autumn. This variation supported the importance of lice in the development of light flecks and spots and suggested a relatively long healing period for the damages induced by lice. PMID:11455905

Studies about diffusion through grain boundary

International Nuclear Information System (INIS)

Allevato, C.E.

1983-01-01

Samples with layers of gold-silver and silver-chromium were deposited in high vacuum (10 -5 -10 -6 Torr) on glass and sodium chloride substrates. After deposition, these films were annealed at different temperatures and analysed by Rutherford Backscattering, Auger Spesctroscopy and Transmission Electron Microscopy. A simulated convolution was done using a computer in order to evalute the precision of the particle detector employed in the backscattering. The concentration profiles used to determine the diffusion coefficient were obtained by Auger electron spectroscopy. This technique demanded a study of sputtering rate to convert time of sputtering in thickness. This rate was determined by two methods. Analyses of the samples of silver-chromium, heated up to 250 0 C, by transmission electron microscopy and Auger electron spectroscopy, indicated the presence of oxide in small isolated regions, as crystallites. Values of the diffusion coefficient and activation energy related to the diffusion through the volume and by the grain boundary were determined by Suzuoka's method. The system Ag/Cr, due to its high grain boundary density, led to an increase of the diffusion coefficient so that this coefficient and the activation energy were obtained only from the grain boundary. (Author) [pt

Grain dissection as a grain size reducing mechanism during ice microdynamics

Science.gov (United States)

Steinbach, Florian; Kuiper, Ernst N.; Eichler, Jan; Bons, Paul D.; Drury, Martin R.; Griera, Albert; Pennock, Gill M.; Weikusat, Ilka

2017-04-01

Ice sheets are valuable paleo-climate archives, but can lose their integrity by ice flow. An understanding of the microdynamic mechanisms controlling the flow of ice is essential when assessing climatic and environmental developments related to ice sheets and glaciers. For instance, the development of a consistent mechanistic grain size law would support larger scale ice flow models. Recent research made significant progress in numerically modelling deformation and recrystallisation mechanisms in the polycrystalline ice and ice-air aggregate (Llorens et al., 2016a,b; Steinbach et al., 2016). The numerical setup assumed grain size reduction is achieved by the progressive transformation of subgrain boundaries into new high angle grain boundaries splitting an existing grain. This mechanism is usually termed polygonisation. Analogue experiments suggested, that strain induced grain boundary migration can cause bulges to migrate through the whole of a grain separating one region of the grain from another (Jessell, 1986; Urai, 1987). This mechanism of grain dissection could provide an alternative grain size reducing mechanism, but has not yet been observed during ice microdynamics. In this contribution, we present results using an updated numerical approach allowing for grain dissection. The approach is based on coupling the full field theory crystal visco-plasticity code (VPFFT) of Lebensohn (2001) to the multi-process modelling platform Elle (Bons et al., 2008). VPFFT predicts the mechanical fields resulting from short strain increments, dynamic recrystallisation process are implemented in Elle. The novel approach includes improvements to allow for grain dissection, which was topologically impossible during earlier simulations. The simulations are supported by microstructural observations from NEEM (North Greenland Eemian Ice Drilling) ice core. Mappings of c-axis orientations using the automatic fabric analyser and full crystallographic orientations using electron

On Presolar Stardust Grains from CO Classical Novae

Science.gov (United States)

Iliadis, Christian; Downen, Lori N.; José, Jordi; Nittler, Larry R.; Starrfield, Sumner

2018-03-01

About 30%–40% of classical novae produce dust 20–100 days after the outburst, but no presolar stardust grains from classical novae have been unambiguously identified yet. Although several studies claimed a nova paternity for certain grains, the measured and simulated isotopic ratios could only be reconciled, assuming that the grains condensed after the nova ejecta mixed with a much larger amount of close-to-solar matter. However, the source and mechanism of this potential post-explosion dilution of the ejecta remains a mystery. A major problem with previous studies is the small number of simulations performed and the implied poor exploration of the large nova parameter space. We report the results of a different strategy, based on a Monte Carlo technique, that involves the random sampling over the most important nova model parameters: the white dwarf composition; the mixing of the outer white dwarf layers with the accreted material before the explosion; the peak temperature and density; the explosion timescales; and the possible dilution of the ejecta after the outburst. We discuss and take into account the systematic uncertainties for both the presolar grain measurements and the simulation results. Only those simulations that are consistent with all measured isotopic ratios of a given grain are accepted for further analysis. We also present the numerical results of the model parameters. We identify 18 presolar grains with measured isotopic signatures consistent with a CO nova origin, without assuming any dilution of the ejecta. Among these, the grains G270_2, M11-334-2, G278, M11-347-4, M11-151-4, and Ag26 have the highest probability of a CO nova paternity.

PROPERTIES OF DUST GRAINS PROBED WITH EXTINCTION CURVES

International Nuclear Information System (INIS)

Nozawa, Takaya; Fukugita, Masataka

2013-01-01

Modern data of the extinction curve from the ultraviolet to the near-infrared are revisited to study properties of dust grains in the Milky Way (MW) and the Small Magellanic Cloud (SMC). We confirm that the graphite-silicate mixture of grains yields the observed extinction curve with the simple power-law distribution of the grain size but with a cutoff at some maximal size: the parameters are tightly constrained to be q = 3.5 ± 0.2 for the size distribution a –q and the maximum radius a max = 0.24 ± 0.05 μm, for both MW and SMC. The abundance of grains, and hence the elemental abundance, is constrained from the reddening versus hydrogen column density, E(B – V)/N H . If we take the solar elemental abundance as the standard for the MW, >56% of carbon should be in graphite dust, while it is dust /ρ H = 1 / (120 +10 -16 ) for the MW and 1 / (760 +70 -90 ) for the SMC under the elemental abundance constraints. We underline the importance of the wavelength dependence of the extinction curve in the near-infrared in constructing the dust model: if A λ ∝λ –γ with γ ≅ 1.6, the power-law grain-size model fails, whereas it works if γ ≅ 1.8-2.0.

Identification of Accretion as Grain Growth Mechanism in Astrophysically Relevant Water&ice Dusty Plasma Experiment

Science.gov (United States)

Marshall, Ryan S.; Chai, Kil-Byoung; Bellan, Paul M.

2017-03-01

The grain growth process in the Caltech water-ice dusty plasma experiment has been studied using a high-speed camera and a long-distance microscope lens. It is observed that (I) the ice grain number density decreases fourfold as the average grain major axis increases from 20 to 80 μm, (II) the major axis length has a log-normal distribution rather than a power-law dependence, and (III) no collisions between ice grains are apparent. The grains have a large negative charge resulting in strong mutual repulsion and this, combined with the fractal character of the ice grains, prevents them from agglomerating. In order for the grain kinetic energy to be sufficiently small to prevent collisions between ice grains, the volumetric packing factor (I.e., ratio of the actual volume to the volume of a circumscribing ellipsoid) of the ice grains must be less than ˜0.1 depending on the exact relative velocity of the grains in question. Thus, it is concluded that direct accretion of water molecules is very likely to dominate the observed ice grain growth.

Identification of Accretion as Grain Growth Mechanism in Astrophysically Relevant Water–Ice Dusty Plasma Experiment

Energy Technology Data Exchange (ETDEWEB)

Marshall, Ryan S.; Chai, Kil-Byoung; Bellan, Paul M. [Applied Physics and Materials Science, Caltech, Pasadena, CA 91125 (United States)

2017-03-01

The grain growth process in the Caltech water–ice dusty plasma experiment has been studied using a high-speed camera and a long-distance microscope lens. It is observed that (i) the ice grain number density decreases fourfold as the average grain major axis increases from 20 to 80 μ m, (ii) the major axis length has a log-normal distribution rather than a power-law dependence, and (iii) no collisions between ice grains are apparent. The grains have a large negative charge resulting in strong mutual repulsion and this, combined with the fractal character of the ice grains, prevents them from agglomerating. In order for the grain kinetic energy to be sufficiently small to prevent collisions between ice grains, the volumetric packing factor (i.e., ratio of the actual volume to the volume of a circumscribing ellipsoid) of the ice grains must be less than ∼0.1 depending on the exact relative velocity of the grains in question. Thus, it is concluded that direct accretion of water molecules is very likely to dominate the observed ice grain growth.

Grain-size sorting and slope failure in experimental subaqueous grain flows

NARCIS (Netherlands)

Kleinhans, M.G.; Asch, Th.W.J. van

2005-01-01

Grain-size sorting in subaqueous grain flows of a continuous range of grain sizes is studied experimentally with three mixtures. The observed pattern is a combination of stratification and gradual segregation. The stratification is caused by kinematic sieving in the grain flow. The segregation is

Climate impact of idealized winter polar mesospheric and stratospheric ozone losses as caused by energetic particle precipitation

Directory of Open Access Journals (Sweden)

K. Meraner

2018-01-01

Full Text Available Energetic particles enter the polar atmosphere and enhance the production of nitrogen oxides and hydrogen oxides in the winter stratosphere and mesosphere. Both components are powerful ozone destroyers. Recently, it has been inferred from observations that the direct effect of energetic particle precipitation (EPP causes significant long-term mesospheric ozone variability. Satellites observe a decrease in mesospheric ozone up to 34 % between EPP maximum and EPP minimum. Stratospheric ozone decreases due to the indirect effect of EPP by about 10–15 % observed by satellite instruments. Here, we analyze the climate impact of winter boreal idealized polar mesospheric and polar stratospheric ozone losses as caused by EPP in the coupled Max Planck Institute Earth System Model (MPI-ESM. Using radiative transfer modeling, we find that the radiative forcing of mesospheric ozone loss during polar night is small. Hence, climate effects of mesospheric ozone loss due to energetic particles seem unlikely. Stratospheric ozone loss due to energetic particles warms the winter polar stratosphere and subsequently weakens the polar vortex. However, those changes are small, and few statistically significant changes in surface climate are found.

Importance and role of grain size in free surface cracking prediction of heavy forgings

Energy Technology Data Exchange (ETDEWEB)

Wang, Zhenhua [State Key Laboratory of Metastable Materials Science and Technology, Yanshan University, Qinhuangdao 066004 (China); Key Laboratory of Advanced Forging & Stamping Technology and Science, Yanshan University, Ministry of Education of China, Qinhuangdao 066004 (China); Sun, Shuhua; Wang, Bo [State Key Laboratory of Metastable Materials Science and Technology, Yanshan University, Qinhuangdao 066004 (China); Shi, Zhongping [Key Laboratory of Advanced Forging & Stamping Technology and Science, Yanshan University, Ministry of Education of China, Qinhuangdao 066004 (China); Fu, Wantang, E-mail: wtfu@ysu.edu.cn [State Key Laboratory of Metastable Materials Science and Technology, Yanshan University, Qinhuangdao 066004 (China)

2015-02-11

The importance and role of grain size in predicting surface cracking of heavy forgings were investigated. 18Mn18Cr0.5N steel specimens with four different grain sizes were tensioned between 900 and 1100 °C at a strain rate of 0.1 s{sup −1}. The nucleation sites and crack morphology were analyzed through electron backscatter diffraction analysis, and the fracture morphology was examined using scanning electron microscopy. The nucleation sites were independent of the grain size, and cracks primarily formed at grain boundaries and triple junctions between grains with high Taylor factors. Grains with lower Taylor factors inhibited crack propagation. Strain was found to mainly concentrate near the grain boundaries; thus, a material with a larger grain size cracks more easily because there are fewer grain boundaries. Fine grains can be easily rotated to a lower Taylor factor to further inhibit cracking. The fracture morphology transformed from a brittle to ductile type with a lowering of grain size. At lower temperature, small dimples on the fracture surfaces of specimens with smaller grain sizes were left by single parent grains and the dimple edge was the grain edge. At higher temperature, dimples formed through void coalescence and the dimple edge was the tearing edge. Finally, the relationship between the reduction in area, grain size, and deformation temperature was obtained.

Grain dynamics and plastic properties of highly refined materials

Energy Technology Data Exchange (ETDEWEB)

Lagos, Miguel; Retamal, Cesar, E-mail: mlagos@utalca.c, E-mail: cretamal@utalca.c [Facultad de IngenierI a, Universidad de Talca, Campus Los Niches, Curico (Chile)

2010-12-15

It has been shown that a grain boundary may undergo two competing classes of elastic instability when the in-plane shear stress exceeds the proper critical values. It may buckle acquiring a sinusoidal shape or may develop a periodic series of fissures, separating bands with a sigmoidal profile. The two instabilities lead to grain sliding, but the corresponding expressions relating the relative velocity between adjacent grains with stress do differ. The plastic properties for small strains were calculated for the two force laws, which we called force models A and B. A comparison of the theoretical results with published experimental data shows that model A, while giving predictions within the experimental uncertainties for a series of superplastic aluminium and titanium alloys, fails for Avesta 2304 steel. However, excellent results are obtained when model B is applied for this steel.

Grain dynamics and plastic properties of highly refined materials

International Nuclear Information System (INIS)

Lagos, Miguel; Retamal, Cesar

2010-01-01

It has been shown that a grain boundary may undergo two competing classes of elastic instability when the in-plane shear stress exceeds the proper critical values. It may buckle acquiring a sinusoidal shape or may develop a periodic series of fissures, separating bands with a sigmoidal profile. The two instabilities lead to grain sliding, but the corresponding expressions relating the relative velocity between adjacent grains with stress do differ. The plastic properties for small strains were calculated for the two force laws, which we called force models A and B. A comparison of the theoretical results with published experimental data shows that model A, while giving predictions within the experimental uncertainties for a series of superplastic aluminium and titanium alloys, fails for Avesta 2304 steel. However, excellent results are obtained when model B is applied for this steel.

Grain dynamics and plastic properties of highly refined materials

Science.gov (United States)

Lagos, Miguel; Retamal, César

2010-12-01

It has been shown that a grain boundary may undergo two competing classes of elastic instability when the in-plane shear stress exceeds the proper critical values. It may buckle acquiring a sinusoidal shape or may develop a periodic series of fissures, separating bands with a sigmoidal profile. The two instabilities lead to grain sliding, but the corresponding expressions relating the relative velocity between adjacent grains with stress do differ. The plastic properties for small strains were calculated for the two force laws, which we called force models A and B. A comparison of the theoretical results with published experimental data shows that model A, while giving predictions within the experimental uncertainties for a series of superplastic aluminium and titanium alloys, fails for Avesta 2304 steel. However, excellent results are obtained when model B is applied for this steel.

Properties and Alignment of Interstellar Dust Grains toward Type Ia Supernovae with Anomalous Polarization Curves

Energy Technology Data Exchange (ETDEWEB)

Hoang, Thiem, E-mail: thiemhoang@kasi.re.kr [Korea Astronomy and Space Science Institute 776, Daedeokdae-ro, Yuseong-gu, Daejeon 34055 (Korea, Republic of); Canadian Institute for Theoretical Astrophysics, University of Toronto, 60 St. George Street, Toronto, ON M5S 3H8 (Canada); Institute of Theoretical Physics, Goethe Universität Frankfurt, D-60438 Frankfurt am Main (Germany)

2017-02-10

Recent photometric and polarimetric observations of Type Ia supernovae (SNe Ia) show unusually low total-to-selective extinction ratios ( R {sub V} < 2) and wavelengths of maximum polarization ( λ{sub max} < 0.4 μ m) for several SNe Ia, which indicates peculiar properties of interstellar (IS) dust in the SN-hosted galaxies and/or the presence of circumstellar (CS) dust. In this paper, we use an inversion technique to infer the best-fit grain size distribution and the alignment function of interstellar grains along the lines of sight toward four SNe Ia with anomalous extinction and polarization data (SN 1986G, SN 2006X, SN 2008fp, and SN 2014J). We find that to reproduce low values of R{sub V}, a significant enhancement in the mass of small grains of radius a < 0.1 μ m is required. For SN 2014J, a simultaneous fit to its observed extinction and polarization is unsuccessful if all the data are attributed to IS dust (model 1), but a good fit is obtained when accounting for the contribution of CS dust (model 2). For SN 2008fp, our best-fit results for model 1 show that in order to reproduce an extreme value of λ{sub max} ∼ 0.15 μ m, small silicate grains must be aligned as efficiently as big grains. For this case, we suggest that strong radiation from the SN can induce efficient alignment of small grains in a nearby intervening molecular cloud via the radiative torque (RAT) mechanism. The resulting time dependence polarization from this RAT alignment model can be tested by observing at ultraviolet wavelengths.

Contrasting response of biomass and grain yield to severe drought in Cappelle Desprez and Plainsman V wheat cultivars

Directory of Open Access Journals (Sweden)

Kenny Paul

2016-02-01

Full Text Available We report a case study of natural variations and correlations of some photosynthetic parameters, green biomass and grain yield in Cappelle Desprez and Plainsman V winter wheat (Triticum aestivum L. cultivars, which are classified as being drought sensitive and tolerant, respectively. We monitored biomass accumulation from secondary leaves in the vegetative phase and grain yield from flag leaves in the grain filling period. Interestingly, we observed higher biomass production, but lower grain yield stability in the sensitive Cappelle cultivar, as compared to the tolerant Plainsman cv. Higher biomass production in the sensitive variety was correlated with enhanced water-use efficiency. Increased cyclic electron flow around PSI was also observed in the Cappelle cv. under drought stress as shown by light intensity dependence of the ratio of maximal quantum yields of Photosystem I and Photosystem II, as well by the plot of the Photosystem I electron transport rate as a function of Photosystem II electron transport rate. Higher CO2 uptake rate in flag leaves of the drought-stressed Plainsman cv. during grain filling period correlates well with its higher grain yield and prolonged transpiration rate through spikes. The increase in drought factor (DFI and performance (PI indices calculated from variable chlorophyll fluorescence parameters of secondary leaves also showed correlation with higher biomass in the Cappelle cultivar during the biomass accumulation period. However, during the grain filling period, DFI and PI parameters of the flag leaves were higher in the tolerant Plainsman V cultivar and showed correlation with grain yield stability. Our results suggest that overall biomass and grain yield may respond differentially to drought stress in different wheat cultivars and therefore phenotyping for green biomass cannot be used as a general approach to predict grain yield. We also conclude that photosynthetic efficiency of flag and secondary leaves

Grain-dependent responses of mammalian diversity to land use and the implications for conservation set-aside.

Science.gov (United States)

Wearn, Oliver R; Carbone, Chris; Rowcliffe, J Marcus; Bernard, Henry; Ewers, Robert M

2016-07-01

Diversity responses to land-use change are poorly understood at local scales, hindering our ability to make forecasts and management recommendations at scales which are of practical relevance. A key barrier in this has been the underappreciation of grain-dependent diversity responses and the role that β-diversity (variation in community composition across space) plays in this. Decisions about the most effective spatial arrangement of conservation set-aside, for example high conservation value areas, have also neglected β-diversity, despite its role in determining the complementarity of sites. We examined local-scale mammalian species richness and β-diversity across old-growth forest, logged forest, and oil palm plantations in Borneo, using intensive camera- and live-trapping. For the first time, we were able to investigate diversity responses, as well as β-diversity, at multiple spatial grains, and across the whole terrestrial mammal community (large and small mammals); β-diversity was quantified by comparing observed β-diversity with that obtained under a null model, in order to control for sampling effects, and we refer to this as the β-diversity signal. Community responses to land use were grain dependent, with large mammals showing reduced richness in logged forest compared to old-growth forest at the grain of individual sampling points, but no change at the overall land-use level. Responses varied with species group, however, with small mammals increasing in richness at all grains in logged forest compared to old-growth forest. Both species groups were significantly depauperate in oil palm. Large mammal communities in old-growth forest became more heterogeneous at coarser spatial grains and small mammal communities became more homogeneous, while this pattern was reversed in logged forest. Both groups, however, showed a significant β-diversity signal at the finest grain in logged forest, likely due to logging-induced environmental heterogeneity. The �

Distributed generation in small remote Northern communities

International Nuclear Information System (INIS)

Malcolm, D.G.

2012-01-01

The presentation discusses the physical and social challenges of reliable and environmentally sound electricity generation in remote northern communities in Canada. There are several hundred remote communities in the boreal region of Canada and throughout the Arctic. Electrical energy requirements are usually a few megawatts. Access to some Arctic remote communities is by air and small water craft only, except when winters are cold enough for winter roads to be constructed for a few weeks each year. These communities, as well as new mining operations and their camp communities, provide a market segment for small reactors. However, there are social acceptance hurdles to be addressed. Trust-building is a must when working with First Nations, Metis, and Inuit communities, and this requires community presence long before proposals for new generation facilities are presented.

Distributed generation in small remote Northern communities

Energy Technology Data Exchange (ETDEWEB)

Malcolm, D.G. [Yellowknife, North West Territories (Canada)

2012-07-01

The presentation discusses the physical and social challenges of reliable and environmentally sound electricity generation in remote northern communities in Canada. There are several hundred remote communities in the boreal region of Canada and throughout the Arctic. Electrical energy requirements are usually a few megawatts. Access to some Arctic remote communities is by air and small water craft only, except when winters are cold enough for winter roads to be constructed for a few weeks each year. These communities, as well as new mining operations and their camp communities, provide a market segment for small reactors. However, there are social acceptance hurdles to be addressed. Trust-building is a must when working with First Nations, Metis, and Inuit communities, and this requires community presence long before proposals for new generation facilities are presented.

36 CFR 1002.19 - Winter activities.

Science.gov (United States)

2010-07-01

... RECREATION § 1002.19 Winter activities. (a) Skiing, snowshoeing, ice skating, sledding, innertubing, tobogganing and similar winter sports are prohibited on Presidio Trust roads and in parking areas open to...

Snow Tweets: Emergency Information Dissemination in a US County During 2014 Winter Storms.

Science.gov (United States)

Bonnan-White, Jess; Shulman, Jason; Bielecke, Abigail

2014-12-22

This paper describes how American federal, state, and local organizations created, sourced, and disseminated emergency information via social media in preparation for several winter storms in one county in the state of New Jersey (USA). Postings submitted to Twitter for three winter storm periods were collected from selected organizations, along with a purposeful sample of select private local users. Storm-related posts were analyzed for stylistic features (hashtags, retweet mentions, embedded URLs). Sharing and re-tweeting patterns were also mapped using NodeXL. RESULTS indicate emergency management entities were active in providing preparedness and response information during the selected winter weather events. A large number of posts, however, did not include unique Twitter features that maximize dissemination and discovery by users. Visual representations of interactions illustrate opportunities for developing stronger relationships among agencies. Whereas previous research predominantly focuses on large-scale national or international disaster contexts, the current study instead provides needed analysis in a small-scale context. With practice during localized events like extreme weather, effective information dissemination in large events can be enhanced.

Impurity effects on the grain boundary cohesion in copper

Science.gov (United States)

Li, Yunguo; Korzhavyi, Pavel A.; Sandström, Rolf; Lilja, Christina

2017-12-01

Segregated impurities at grain boundaries can dramatically change the mechanical behavior of metals, while the mechanism is still obscure in some cases. Here, we suggest a unified approach to investigate segregation and its effects on the mechanical properties of polycrystalline alloys using the example of 3 s p impurities (Mg, Al, Si, P, or S) at a special type Σ 5 (310 )[001 ] tilt grain boundary in Cu. We show that for these impurities segregating to the grain boundary, the strain contribution to the work of grain boundary decohesion is small and that the chemical contribution correlates with the electronegativity difference between Cu and the impurity. The strain contribution to the work of dislocation emission is calculated to be negative, while the chemical contribution is calculated to be always positive. Both the strain and chemical contributions to the work of dislocation emission generally become weaker with the increasing electronegativity from Mg to S. By combining these contributions together, we find, in agreement with experimental observations, that a strong segregation of S can reduce the work of grain boundary separation below the work of dislocation emission, thus embrittling Cu, while such an embrittlement cannot be produced by a P segregation because it lowers the energy barrier for dislocation emission relatively more than for work separation.

Photoelectric Emission Measurements on the Analogs of Individual Cosmic Dust Grains

Science.gov (United States)

Abbas, M. M.; Tankosic, D.; Craven, P. D.; Spann, J. F.; LeClair, A.; West, E. A.; Weingartner, J. C.; Tielens, A. G. G. M.; Nuth, J. a.; Camata, R. P.

2006-01-01

The photoelectric emission process is considered to be the dominant mechanism for charging of cosmic dust grains in many astrophysical environments. The grain charge and equilibrium potentials play an important role in the dynamical and physical processes that include heating of the neutral gas in the interstellar medium, coagulation processes in the dust clouds, and levitation and dynamical processes in the interplanetary medium and planetary surfaces and rings. An accurate evaluation of photoelectric emission processes requires knowledge of the photoelectric yields of individual dust grains of astrophysical composition as opposed to the values obtained from measurements on flat surfaces of bulk materials, as it is generally assumed on theoretical considerations that the yields for the small grains are much different from the bulk values. We present laboratory measurements of the photoelectric yields of individual dust grains of silica, olivine, and graphite of approx. 0.09-5 micrometer radii levitated in an electrodynamic balance and illuminated with ultraviolet radiation at 120-160 nm wavelengths. The measured yields are found to be substantially higher than the bulk values given in the literature and indicate a size dependence with larger particles having order-of-magnitude higher values than for submicron-size grains.

Grain-size variations on a longitudinal dune and a barchan dune

Science.gov (United States)

Watson, Andrew

1986-01-01

The grain-size characteristics of the sand upon two dunes—a 40 m high longitudinal dune in the central Namib Desert and a 6.0 m high barchan in the Jafurah sand sea of Saudi Arabia—vary with position on the dunes. On the longitudinal dune, median grain size decreases, sorting improves and the grain-size distributions are less skewed and more normalized toward the crest. Though sand at the windward toe is distinct, elsewhere on the dune the changes in grain-size characteristics are gradual. An abrupt change in grain size and sorting near the crest—as described by Bagnold (1941, pp. 226-229)—is not well represented on this dune. Coarse grains remain as a lag on concave slope units and small particles are winnowed from the sand on the steepest windward slopes near the crest. Avalanching down slipfaces at the crest acts only as a supplementary grading mechanism. On the barchan dune median grain size also decreases near the crest, but sorting becomes poorer, though the grain-size distributions are more symmetric and more normalized. The dune profile is a Gaussian curve with a broad convex zone at the apex upon which topset beds had accreted prior to sampling. Grain size increases and sorting improves down the dune's slipface. However, this grading mechanism does not influence sand on the whole dune because variations in wind regime bring about different modes of dune accretion. On both dunes, height and morphology appear to influence significantly the grain-size characteristics.

Polymorphism of proteins in selected slovak winter wheat genotypes using SDS-PAGE

Directory of Open Access Journals (Sweden)

Dana Miháliková

2016-12-01

Full Text Available Winter wheat is especially used for bread-making. The specific composition of the grain storage proteins and the representation of individual subunits determines the baking quality of wheat. The aim of this study was to analyze 15 slovak varieties of the winter wheat (Triticum aestivum L. based on protein polymorphism and to predict their technological quality. SDS-PAGE method by ISTA was used to separate glutenin protein subunits. Glutenins were separated into HMW-GS (15.13% and LMW-GS (65.89% on the basis of molecular weight in SDS-PAGE. At the locus Glu-A1 was found allele Null (53% of genotypes and allele 1 (47% of genotypes. The locus Glu-B1 was represented by the HMW-GS subunits 6+8 (33% of genotypes, 7+8 (27% of genotypes, 7+9 (40% of genotypes. At the locus Glu-D1 were detected two subunits, 2+12 (33% of genotypes and 5+10 (67% of genotypes which is correlated with good bread-making properties. The Glu – score was ranged from 4 (genotype Viglanka to 10 (genotypes Viola, Vladarka. According to the representation of individual glutenin subunits in samples, the dendrogram of genetic similarity was constructed. By the prediction of quality the results showed that the best technological quality was significant in the varieties Viola and Vladarka which are suitable for use in food processing.

Impact of Climate Change Effects on Contamination of Cereal Grains with Deoxynivalenol

DEFF Research Database (Denmark)

van der Fels-Klerx, H J; van Asselt, E D; Madsen, M S

2013-01-01

Climate change is expected to aggravate feed and food safety problems of crops; however, quantitative estimates are scarce. This study aimed to estimate impacts of climate change effects on deoxynivalenol contamination of wheat and maize grown in the Netherlands by 2040. Quantitative modelling...... the impacts of climate change effects on food safety, and of considering both direct and indirect effects when assessing climate change impacts on crops and related food safety hazards....... two different global and regional climate model combinations were used. A weather generator was applied for downscaling climate data to local conditions. Crop phenology models and prediction models for DON contamination used, each for winter wheat and grain maize. Results showed that flowering...

Neuro - Fuzzy Analysis for Silicon Carbide Abrasive Grains ...

African Journals Online (AJOL)

Grinding wheels are made of very small, sharp and hard abrasive materials or grits held together by strong porous bond. Abrasive materials are materials of extreme hardness that are used to shape other materials by a grinding or abrading action and they are used either as loose grains, as grinding wheels, or as coatings ...

Surface wind energy trends near Taiwan in winter since 1871

Directory of Open Access Journals (Sweden)

Lei Zhang

2017-01-01

Full Text Available The tropical surface wind speed in boreal winter reaches a maximum near Taiwan. This stable wind resource may be used for future clean energy development. How this surface wind energy source has changed in past 141 years is investigated using the 20th century reanalysis dataset and CMIP5 models. Our observational analysis shows that the surface wind speed experienced a weakening trend in the past 141 years (1871 - 2010. The average decreasing rate is around -1.4 m s-1 per century. The decrease is primarily attributed to the relative sea surface temperature (SST cooling in the subtropical North Pacific, which forces a large-scale low-level anti-cyclonic circulation anomaly in situ and is thus responsible for the southerly trend near Taiwan. The relative SST trend pattern is attributed mainly to the greenhouse gas effect associated with anthropogenic activities. The southerly trend near Taiwan is more pronounced in the boreal winter than in summer. Such seasonal difference is attributed to the reversed seasonal mean wind, which promotes more efficient positive feedback in the boreal winter. The CMIP5 historical run analysis reveals that climate models capture less SST warming and large-scale anti-cyclonic circulation in the subtropical North Pacific, but the simulated weakening trend of the surface wind speed near Taiwan is too small.

A comparison of grain boundary evolution during grain growth in fcc metals

International Nuclear Information System (INIS)

Brons, J.G.; Thompson, G.B.

2013-01-01

Grain growth of Cu and Ni thin films, subjected to in situ annealing within a transmission electron microscope, has been quantified using a precession-enhanced electron diffraction technique. The orientation of each grain and its misorientation with respect to its neighboring grains were calculated. The Cu underwent grain growth that maintained a monomodal grain size distribution, with its low-angle grain boundaries being consumed, and the Ni exhibited grain size distributions in stages, from monomodal to bimodal to monomodal. The onset of Ni’s abnormal grain growth was accompanied by a sharp increase in the Σ3 and Σ9 boundary fractions, which is attributed to simulation predictions of their increased mobility. These Σ3 and Σ9 fractions then dropped to their room temperature values during the third stage of grain growth. In addition to the Σ3 and Σ9 boundaries, the Σ5 and Σ7 boundaries also underwent an increase in total boundary fraction with increasing temperature in both metals

Transfer factor of "9"0Sr and "1"3"7Cs to lettuce and winter wheat at different growth stage applications

International Nuclear Information System (INIS)

Al Attar, Lina; Al-Oudat, Mohammad; Safia, Bassam; Ghani, Basem Abdul

2015-01-01

The effect of clay soil contamination time on the transfer factors (F_vs) of "1"3"7Cs and "9"0Sr was investigated in four different growth stages of winter wheat and lettuce crops. The experiment was performed in an open field using lysimeters. The F_vs were the ratio of the activity concentrations of the radionuclides in crops to those in soil, both as dry weight (Bq kg"−"1). Significant difference of log-F_vs was evaluated using one-way Analysis of Variance (ANOVA). Basically, F_vs of "9"0Sr were higher than those of "1"3"7Cs, despite of the application stage or crop' variety. Higher F_vs for both radionuclides were observed for lettuce in comparison to winter wheat. F_vs of "9"0Sr showed comparable trends for both crops with enhanced F_vs obtained when contamination occurred in early stages, i.e. 1.20 for lettuce and 0.88 and 0.02 for winter wheat, straw and grains, respectively. Despite the fluctuation noted in the pattern of F_vs for "1"3"7Cs, soil contaminated at the second stage gave the highest F_vs for lettuce and grains, with geometric means of 0.21 and 0.01, respectively. However, wheat-straw showed remarkable increase in F_v for the latest contamination (ripening stage), about 0.06. It could be concluded that soil contamination at early growth stages would represent high radiological risk for the scenarios studied with an exception to "1"3"7Cs in winter wheat-straw which reflected greater hazard at the latest application. - Highlights: • Higher TFs for both radionuclides were observed for leafy plant in comparison to cereals. • Despite the growth stages & plants' variety, TFs of "9"0Sr were always higher than those of "1"3"7Cs. • TFs of "9"0Sr showed comparable trends in both crops and were higher at earlier growth stages. • Fluctuation noted in TFs for "1"3"7Cs in lettuce with higher TFs at second contamination-stage. • High TFs for "1"3"7Cs when contamination occurred at the latest growth stage of wheat vegetative.

Examining winter visitor use in Yellowstone National Park

Science.gov (United States)

Mae A. Davenport; Wayne A. Freimund; William T. Borrie; Robert E. Manning; William A. Valliere; Benjamin Wang

2000-01-01

This research was designed to assist the managers of Yellowstone National Park (YNP) in their decision making about winter visitation. The focus of this report is on winter use patterns and winter visitor preferences. It is the author’s hope that this information will benefit both the quality of winter experiences and the stewardship of the park resources. This report...

Investigation of microorganisms involved in biosynthesis of the kefir grain.

Science.gov (United States)

Wang, Sheng-Yao; Chen, Kun-Nan; Lo, Yung-Ming; Chiang, Ming-Lun; Chen, Hsi-Chia; Liu, Je-Ruei; Chen, Ming-Ju

2012-12-01

The purpose of this study was to understand the significance of each microorganism in grain formation by evaluating their microbial aggregation and cell surface properties during co-aggregation of LAB and yeasts together with an investigation of biofilm formation. Non-grain forming strains from viili were also evaluated as a comparison. Results indicated that the kefir grain strains, Lactobacillus kefiranofaciens and Saccharomyces turicensis possess strong auto-aggregation ability and that Lactobacillus kefiri shows significant biofilm formation properties. Significant co-aggregation was noted when S. turicensis and kefir LAB strains (Lb. kefiranofaciens and Lb. kefiri) were co-cultured. Most of the tested LAB strains are hydrophilic and had a negative charge on their cell surface. Only the kefir LAB strains, Lb. kefiranofaciens HL1 and Lb. kefiri HL2, possessed very high hydrophobicity and had a positive cell surface charge at pH 4.2. In contrast, the LAB and yeasts in viili did not show any significant self-aggregation or biofilm formation. Based on the above results, we propose that grain formation begins with the self-aggregation of Lb. kefiranofaciens and S. turicensis to form small granules. At this point, the biofilm producer, Lb. kefiri, then begins to attach to the surface of granules and co-aggregates with other organisms and components in the milk to form the grains. On sub-culturing, more organisms attach to the grains resulting in grain growth. When investigated by scanning electron microscopy, it was found that short-chain lactobacilli such as Lb. kefiri occupy the surface, while long-chain lactobacilli such as Lb. kefiranofaciens have aggregated towards the center of the kefir grains. These findings agree with the above hypothesis on the formation of grains. Taken together, this study demonstrates the importance of cell surface properties together with fermentation conditions to the formation of grains in kefir. Copyright © 2012 Elsevier Ltd. All

Winter Dew Harvest in Mexico City

Directory of Open Access Journals (Sweden)

Arias-Torres Jorge Ernesto

2015-12-01

Full Text Available This study presents experimental and theoretical results of winter dew harvest in México City in terms of condensation rate. A simplified theoretical model based on a steady-state energy balance on a radiator-condenser was fitted, as a function of the ambient temperature, the relative humidity and the wind velocity. A glass sheet and aluminum sheet white-painted were used as samples over the outdoor experiments. A good correlation was obtained between the theoretical and experimental data. The experimental results show that there was condensation in 68% of the winter nights on both condensers. The total winter condensed mass was 2977 g/m2 and 2888 g/m2 on the glass sheet and aluminum sheet white-painted, respectively. Thus, the condensed mass on the glass was only 3% higher than that on the painted surface. The maximum nightly dew harvests occurred during December, which linearly reduced from 50 g/m2 night to 22 g/m2 night as the winter months went by. The condensation occurred from 1:00 a.m. to 9:00 a.m., with maximum condensation rates between 6:00 a.m. and 7:00 a.m. The dew harvest can provide a partial alternative to the winter water shortage in certain locations with similar climates to the winter in Mexico City, as long as pollution is not significant.

Grain size dependence of the critical current density in YBa2Cu3Ox superconductors

International Nuclear Information System (INIS)

Kuwabara, M.; Shimooka, H.

1989-01-01

The grain size dependence of the critical current density in bulk single-phase YBa 2 Cu 3 O x ceramics was investigated. The grain size of the materials was changed to range approximately from 1.0 to 25 μm by changing the conditions of power processing and sintering, associated with an increase in the sintered density of the materials with increasing grain size. The critical current density has been found to exhibit a significant grain size dependence, changing from 880 A/cm 2 to a value of 100 A/cm 2 with a small increase in the average grain size from 1.2 to 2.0 μm. This seems to provide information about the nature of the weak link between superconducting grains which might govern the critical current density of the materials

The spatial distribution of microfabric around gravel grains: indicator of till formation processes

Science.gov (United States)

KalväNs, Andis; Saks, Tomas

2010-05-01

Till micromorphology studies in thin sections is an established tool in the field of glacial geology. Often the thin sections are inspected only visually with help of mineralogical microscope. This can lead to subjective interpretation of observed structures. More objective method used in till micromorphology is measurement of apparent microfabric, usually seen as preferred orientation of elongated sand grains. In theses studies only small fraction of elongated sand grains often confined to small area of thin section usually are measured. We present a method for automated measurement of almost all elongated sand grains across the full area of the thin section. Apparently elongated sand grains are measured using simple image analysis tools, the data are processed in a way similar to regular till fabric data and visualised as a grid of rose diagrams. The method allows to draw statistical information about spatial variation of microfabric preferred orientation and fabric strength with resolution as fine as 1 mm. Late Weichselian tills from several sites in Western Latvia were studied and large variations in fabric strength and spatial distribution were observed in macroscopically similar till units. The observed types of microfabric spatial distributions include strong, monomodal and uniform distribution; weak and highly variable in small distances distribution; consistently bimodal distribution and domain-like pattern of preferred sand grain orientation. We suggest that the method can be readily used to identify the basic deformation and sedimentation processes active during the final stages of till formation. It is understood that the microfabric orientation will be significant affected by nearby large particles. The till is highly heterogonous sediment and the source of microfabric perturbations observed in thin section might lie outside the section plane. Therefore we suggest that microfabric distribution around visible sources of perturbation - gravel grains cut

TRAJECTORIES AND DISTRIBUTION OF INTERSTELLAR DUST GRAINS IN THE HELIOSPHERE

Energy Technology Data Exchange (ETDEWEB)

Slavin, Jonathan D. [Harvard-Smithsonian Center for Astrophysics, MS 83, 60 Garden Street, Cambridge, MA 02138 (United States); Frisch, Priscilla C. [Department of Astronomy and Astrophysics, University of Chicago, 5460 S. Ellis Avenue, Chicago, IL 60637 (United States); Mueller, Hans-Reinhard [Department of Physics and Astronomy, Dartmouth College, Hanover, NH 03755 (United States); Heerikhuisen, Jacob; Pogorelov, Nikolai V. [Department of Physics and Center for Space Physics and Aeronomic Research, University of Alabama, Huntsville, AL 35899 (United States); Reach, William T. [Universities Space Research Association, MS 211-3, Moffett Field, CA 94035 (United States); Zank, Gary [Department of Physics and Center for Space Plasma and Aeronomic Research, University of Alabama, Huntsville, AL 35805 (United States)

2012-11-20

The solar wind carves a bubble in the surrounding interstellar medium (ISM) known as the heliosphere. Charged interstellar dust grains (ISDG) encountering the heliosphere may be diverted around the heliopause or penetrate it depending on their charge-to-mass ratio. We present new calculations of trajectories of ISDG in the heliosphere, and the dust density distributions that result. We include up-to-date grain charging calculations using a realistic UV radiation field and full three-dimensional magnetohydrodynamic fluid + kinetic models for the heliosphere. Models with two different (constant) polarities for the solar wind magnetic field (SWMF) are used, with the grain trajectory calculations done separately for each polarity. Small grains a {sub gr} {approx}< 0.01 {mu}m are completely excluded from the inner heliosphere. Large grains, a {sub gr} {approx}> 1.0 {mu}m, pass into the inner solar system and are concentrated near the Sun by its gravity. Trajectories of intermediate size grains depend strongly on the SWMF polarity. When the field has magnetic north pointing to ecliptic north, the field de-focuses the grains resulting in low densities in the inner heliosphere, while for the opposite polarity the dust is focused near the Sun. The ISDG density outside the heliosphere inferred from applying the model results to in situ dust measurements is inconsistent with local ISM depletion data for both SWMF polarities but is bracketed by them. This result points to the need to include the time variation in the SWMF polarity during grain propagation. Our results provide valuable insights for interpretation of the in situ dust observations from Ulysses.

Leadership in American Indian Communities: Winter Lessons

Science.gov (United States)

Metoyer, Cheryl A.

2010-01-01

Winter lessons, or stories told in the winter, were one of the ways in which tribal elders instructed and directed young men and women in the proper ways to assume leadership responsibilities. Winter lessons stressed the appropriate relationship between the leader and the community. The intent was to remember the power and purpose of that…

Assesment of winter wheat advanced lines by use of multivariate statistical analyses

Directory of Open Access Journals (Sweden)

Boshev Dane

2016-01-01

Full Text Available This study was conducted to evaluate 49 advanced lines of winter wheat (Triticum aestivum L. for their morphoagronomic traits and to determine best criteria for selection of lines to be included in future breeding program. The material was assessed in two years experiment at two locations, using RCBD design with three replications. Ten quantitative traits: plant height, number of fertile tillers, spike length, number of spikelets per spike, number of grains per spike, weight of grain per spike and per plant, fertility, biological yield and harvest index were evaluated by PCA and two-way cluster analysis. Three main principal components were determined explaining 71.391% of the total variation among the genotypes. One third of the variation is explained by PC1 which reflects the genotype yield potential. PC2 and PC3 explained 25.22% and 15.49% of the total variance, mostly in relation to the plant height and spike components, respectively. Biplot graph revealed strongest positive association between spike length, number of spikelets and biological yield and between number of tillers, weight of grains per spike and per plant. Two-way cluster analysis resulted with a dendrogram with one solely separated genotype, superior for all traits and two main clusters of genotypes defined with wide genetic diversity especially between the groups within the second cluster. Genotypes with high values for specific traits will be included in the future breeding programmes. Classification of genotypes and the extend of variation among them illustrated on the heatmap has proved to be practical tool for selecting genotypes with desired traits in the early stages of the breeding process.

Ion drag force on dust grains in the magnetized edge plasma

International Nuclear Information System (INIS)

Matyash, K.; Schneider, R.; Ikkurthi, V.R.; Melzer, A.

2009-01-01

A 3-dimensional Particle-Particle Particle-Mesh (P3M) code [K. Matyash, R. Schneider, F. Taccogna, D. Tskhakaya, J. Nucl. Mater. 363-365 (2007) 458] is applied to simulate a small-size (smaller than a Debye length) spherical dust grain confined in the magnetized plasma near the material wall of a tokamak. Plasma particles (electrons and ions) are treated kinetically (Particle-in-Cell with Monte Carlo Collisions (PIC MCC)), which allows to resolve self-consistently the electrostatic sheath in front of the wall. In order to describe accurately the plasma particles' motion close to the dust grain, the PIC technique is supplemented with Molecular Dynamics (MD), employing an analytic electrostatic potential for the interaction with the dust grain. The charging of a spherical, conducting dust grain confined in the sheath potential close to the wall of a tokamak is simulated. A magnetic field normal to the wall was investigated. The ion drag force resulting from dust grain collisions with the streaming ions is calculated. This force is critical for a realistic description of the dust particle dynamics and transport in fusion plasmas.

Grain boundaries in Ni3Al. 2

International Nuclear Information System (INIS)

Kung, H.; Sass, S.L.

1992-01-01

This paper discusses the dislocation structure of small angle tilt and twist boundaries in ordered Ni 3 Al, with and without boron, investigated using transmission electron microscopy. Dislocation with Burgers vectors that correspond to anti-phase boundary (APB)-coupled superpartials were found in small angle twist boundaries in both boron-free and boron-doped Ni 3 Al, and a small angle tilt boundary in boron-doped Ni 3 Al. The boundary structures are in agreement with theoretical models proposed by Marcinkowski and co-workers. The APB energy determined from the dissociation of the grain boundary dislocations was lower than values reported for isolated APBs in Ni 3 Al. For small angle twist boundaries the presence of boron reduced the APB energy at the interface until it approached zero. This is consistent with the structure of these boundaries containing small regions of increased compositional disorder in the first atomic plane next to the interface

Application of binomial and multinomial probability statistics to the sampling design process of a global grain tracing and recall system

Science.gov (United States)

Small, coded, pill-sized tracers embedded in grain are proposed as a method for grain traceability. A sampling process for a grain traceability system was designed and investigated by applying probability statistics using a science-based sampling approach to collect an adequate number of tracers fo...

TRAJECTORIES AND DISTRIBUTION OF INTERSTELLAR DUST GRAINS IN THE HELIOSPHERE

International Nuclear Information System (INIS)

Slavin, Jonathan D.; Frisch, Priscilla C.; Müller, Hans-Reinhard; Heerikhuisen, Jacob; Pogorelov, Nikolai V.; Reach, William T.; Zank, Gary

2012-01-01

The solar wind carves a bubble in the surrounding interstellar medium (ISM) known as the heliosphere. Charged interstellar dust grains (ISDG) encountering the heliosphere may be diverted around the heliopause or penetrate it depending on their charge-to-mass ratio. We present new calculations of trajectories of ISDG in the heliosphere, and the dust density distributions that result. We include up-to-date grain charging calculations using a realistic UV radiation field and full three-dimensional magnetohydrodynamic fluid + kinetic models for the heliosphere. Models with two different (constant) polarities for the solar wind magnetic field (SWMF) are used, with the grain trajectory calculations done separately for each polarity. Small grains a gr ∼ gr ∼> 1.0 μm, pass into the inner solar system and are concentrated near the Sun by its gravity. Trajectories of intermediate size grains depend strongly on the SWMF polarity. When the field has magnetic north pointing to ecliptic north, the field de-focuses the grains resulting in low densities in the inner heliosphere, while for the opposite polarity the dust is focused near the Sun. The ISDG density outside the heliosphere inferred from applying the model results to in situ dust measurements is inconsistent with local ISM depletion data for both SWMF polarities but is bracketed by them. This result points to the need to include the time variation in the SWMF polarity during grain propagation. Our results provide valuable insights for interpretation of the in situ dust observations from Ulysses.

[Flag leaf photosynthetic characteristics, change in chlorophyll fluorescence parameters, and their relationships with yield of winter wheat sowed in spring].

Science.gov (United States)

Xu, Lan; Gao, Zhi-qang; An, Wei; Li, Yan-liang; Jiao, Xiong-fei; Wang, Chuang-yun

2016-01-01

With five good winter wheat cultivars selected from the middle and lower reaches of Yangtze River and Southwest China as test materials, a field experiment in Xinding basin area of Shanxi Province was conducted to study the photosynthetic characteristics, chlorophyll content, and chlorophyll fluorescence parameters of flag leaf at different sowing dates, as well as the correlations between these indices and yield for two years (2013-2014). The results showed that the difference in most fluorescence parameters except chlorophyll content among cultivars was significant. The correlations between these fluorescence parameters and yield were significant. The variation coefficient of chlorophyll (Chl) content was low (0.12-0.17), and that of performance index based on absorption (PIabs) was high (0.32-0.39), with the partial correlation coefficients of them with grain yield from 2013 to 2014 ranged in 0.70-0.81. Under the early sowing condition, the grain yield positively correlated with PIabs at flowering and filling stages and chlorophyll content at grain filling stage, but negatively correlated with the relative variable fluorescence at I point (Vi) at grain filling stage. About 81.1%-82.8% of grain yield were determined by the variations of PIabs, Chl, and Vi. Wheat cultivars had various performances in the treatments with different sowing dates and a consistent trend was observed in the two experimental years. Among these 5 cultivars, Yangmai 13 was suitable for early sowing, with the flag leaf photosynthetic rate (Pn), Chl, most fluorescence parame-ters, and grain yield showed obviously high levels. In conclusion, under early sowing condition chlorophyll content at grain filling stages, PIabs at flowering and filling stages, and Pn were important indices for selecting wheat cultivars with high photosynthetic efficiency.

A new approach to grain refinement of an Mg-Li-Al cast alloy

International Nuclear Information System (INIS)

Jiang, B.; Qiu, D.; Zhang, M.-X.; Ding, P.D.; Gao, L.

2010-01-01

Crystallographic calculation based on the edge-to-edge matching model predicted that both TiB 2 and Al 3 Ti intermetallic compounds have strong potential to be effective grain refiners for β phase in the Mg-14Li-1Al alloy due to the small atomic matching misfit across the interface between the compounds and β phase. Experimental results showed that addition of 1.25 wt%Al-5Ti-1B master alloy reduced grain size of β phase in the alloy from 1750 to 500 μm. The possible grain refining mechanisms were also discussed.

The effect of tillage intensity on soil structure and winter wheat root/shoot growth

DEFF Research Database (Denmark)

Munkholm, Lars Juhl; Hansen, Elly Møller; Olesen, Jørgen E

2008-01-01

was followed during the growing seasons using spectral reflectance and mini-rhizotron measurements, respectively. A range of soil physical properties were measured. We found decreased early season shoot and root growth with decreasing tillage intensity. Differences diminished later in the growing season...... of this study was to investigate the effect of tillage intensity on crop growth dynamics and soil structure. A tillage experiment was established in autumn 2002 on two Danish sandy loams (Foulum and Flakkebjerg) in a cereal-based crop rotation. The tillage systems included in this study were direct drilling (D...... with decreasing tillage intensity for the first year winter wheat at Foulum. In general ploughing resulted in the highest grain yields. This study highlights the important interaction between soil structure and crop growth dynamics....

[Effects of Short-time Conservation Tillage Managements on Greenhouse Gases Emissions from Soybean-Winter Wheat Rotation System].

Science.gov (United States)

Xie, Yan; Chen, Xi; Hu, Zheng-hua; Chen, Shu-tao; Zhang, Han; Ling, Hui; Shen, Shuang-he

2016-04-15

Field experiments including one soybean growing season and one winter-wheat growing season were adopted. The experimental field was divided into four equal-area sub-blocks which differed from each other only in tillage managements, which were conventional tillage (T) , no-tillage with no straw cover ( NT) , conventional tillage with straw cover (TS) , and no-tillage with straw cover (NTS). CO₂ and N₂O emission fluxes from soil-crop system were measured by static chamber-gas chromatograph technique. The results showed that: compared with T, in the soybean growing season, NTS significantly increased the cumulative amount of CO₂ (CAC) from soil-soybean system by 27.9% (P = 0.045) during the flowering-podding stage, while NT significantly declined CAC by 28.9% (P = 0.043) during the grain filling-maturity stage. Compared with T, NT significantly declined the cumulative amount of N₂O (CAN) by 28.3% (P = 0.042) during the grain filling-maturity stage. In the winter-wheat growing season, compared with T, TS and NT significantly declined CAC by 24.3% (P = 0.032) and 36.0% (P = 0.041) during the elongation-booting stage, and also declined CAC by 26.8% (P = 0.027) and 33.1% (P = 0.038) during the maturity stage. During the turning-green stage, compared with T treatment, NT, NTS, and TS treatments had no significant effect on CAN, while NTS significant declined CAN by 42.0% (P = 0.035) compared with NT. Our findings suggested that conservation tillage managements had a more significant impact on CO₂ emission than 20 emission from soil-crop system.

Winter climate change and coastal wetland foundation species: salt marshes vs. mangrove forests in the southeastern United States.

Science.gov (United States)

Osland, Michael J; Enwright, Nicholas; Day, Richard H; Doyle, Thomas W

2013-05-01

We live in an era of unprecedented ecological change in which ecologists and natural resource managers are increasingly challenged to anticipate and prepare for the ecological effects of future global change. In this study, we investigated the potential effect of winter climate change upon salt marsh and mangrove forest foundation species in the southeastern United States. Our research addresses the following three questions: (1) What is the relationship between winter climate and the presence and abundance of mangrove forests relative to salt marshes; (2) How vulnerable are salt marshes to winter climate change-induced mangrove forest range expansion; and (3) What is the potential future distribution and relative abundance of mangrove forests under alternative winter climate change scenarios? We developed simple winter climate-based models to predict mangrove forest distribution and relative abundance using observed winter temperature data (1970-2000) and mangrove forest and salt marsh habitat data. Our results identify winter climate thresholds for salt marsh-mangrove forest interactions and highlight coastal areas in the southeastern United States (e.g., Texas, Louisiana, and parts of Florida) where relatively small changes in the intensity and frequency of extreme winter events could cause relatively dramatic landscape-scale ecosystem structural and functional change in the form of poleward mangrove forest migration and salt marsh displacement. The ecological implications of these marsh-to-mangrove forest conversions are poorly understood, but would likely include changes for associated fish and wildlife populations and for the supply of some ecosystem goods and services. © 2012 Blackwell Publishing Ltd.

Flixweed is more competitive than winter wheat under ozone pollution: evidences from membrane lipid peroxidation, antioxidant enzymes and biomass.

Directory of Open Access Journals (Sweden)

Cai-Hong Li

Full Text Available To investigate the effects of ozone on winter wheat and flixweed under competition, two species were exposed to ambient, elevated and high [O3] for 30 days, planted singly or in mixculture. Eco-physiological responses were examined at different [O3] and fumigating time. Ozone reduced the contents of chlorophyll, increased the accumulation of H2O2 and malondialdehyde in both wheat and flixweed. The effects of competition on chlorophyll content of wheat emerged at elevated and high [O3], while that of flixweed emerged only at high [O3]. The increase of H2O2 and malondialdehyde of flixweed was less than that of wheat under the same condition. Antioxidant enzyme activities of wheat and flixweed were seriously depressed by perennial and serious treatment using O3. However, short-term and moderate fumigation increased the activities of SOD and POD of wheat, and CAT of flixweed. The expression levels of antioxidant enzymes related genes provided explanation for these results. Furthermore, the increase of CAT expression of flixweed was much higher than that of SOD and POD expression of wheat. Ozone and competition resulted in significant reductions in biomass and grain yield in both winter wheat and flixweed. However, the negative effects on flixweed were less than wheat. Our results demonstrated that winter wheat is more sensitive to O3 and competition than flixweed, providing valuable data for further investigation on responses of winter wheat to ozone pollution, in particular combined with species competition.

Energy and greenhouse gas profiles of polyhydroxybutyrates derived from corn grain: a life cycle perspective.

Science.gov (United States)

Kim, Seungdo; Dale, Bruce E

2008-10-15

Polyhydroxybutyrates (PHB) are well-known biopolymers derived from sugars orvegetable oils. Cradle-to-gate environmental performance of PHB derived from corn grain is evaluated through life cycle assessment (LCA), particularly nonrenewable energy consumption and greenhouse gas emissions. Site-specific process information on the corn wet milling and PHB fermentation and recovery processes was obtained from Telles. Most of energy used in the corn wet milling and PHB fermentation and recovery processes is generated in a cogeneration power plant in which corn stover, assumed to be representative of a variety of biomass sources that could be used, is burned to generate electricity and steam. County level agricultural information is used in estimating the environmental burdens associated with both corn grain and corn stover production. Results show that PHB derived from corn grain offers environmental advantages over petroleum-derived polymers in terms of nonrenewable energy consumption and greenhouse gas emissions. Furthermore, PHB provides greenhouse gas credits, and thus PHB use reduces greenhouse gas emissions compared to petroleum-derived polymers. Corn cultivation is one of the environmentally sensitive areas in the PHB production system. More sustainable practices in corn cultivation (e.g., using no-tillage and winter cover crops) could reduce the environmental impacts of PHB by up to 72%.

Thermal stability of grain boundaries in nanocrystalline Zn studied by positron lifetime spectroscopy

International Nuclear Information System (INIS)

Zhou Kai; Li Hui; Pang Jinbiao; Wang Zhu

2012-01-01

Nanocrystalline Zn prepared by compacting nanoparticles with mean grain size about 55 nm at 15 MPa has been studied by positron lifetime spectroscopy. For the bulk Zn sample, the vacancy defect is annealed out at about 350 °C, but for the nanocrystalline Zn sample, the vacancy cluster in grain boundaries is quite difficult to be annealed out even at very high temperature (410 °C). In the grain boundaries of nanocrystalline Zn, the small free volume defect (not larger than divacancy) is dominant according to the high relative intensity for the short positron lifetime (τ 1 ). The oxide (ZnO) inside the grain boundaries has been found having an effect to hinder the decrease of average positron lifetime (τ av ), which probably indicates that the oxide stabilizes the microstructure of the grain boundaries. This stabilization is very important for the nanocrystalline materials using as radiation resistant materials.

Landscape Characteristics of Oriental Honey Buzzards Wintering in Western Part of Flores Island Based on Satellite-Tracking Data

Science.gov (United States)

Syartinilia; Farisi, G. H. Al; Higuchi, H.

2017-10-01

Oriental Honey Buzzards (OHBs, Pernis ptilorhynchus) are migratory raptor that has been satellite-tracked since 2003. Some islands in Indonesia which are used for wintering habitat are Flores and Borneo. However, both islands have different characteristics of climate and land cover. The objectives of this research were to analyze the landscape characteristic of the OHBs wintering habitat in western Flores, and to subsequently compare landscape characteristic of the OHBs wintering habitat in Borneo. Landscape habitat characteristics were analyzed using Principal Component Analysis (PCA) combined with GIS and then compared to the previous study in Borneo Island. The result showed that the first of six principal components explained 79.14% and 77.59% of the observed variation in landscape characteristics of both core and edge habitats, subsequently. Habitat selection by OHBs at wintering site was influenced by the availability of thermal wind and food. Savannah was identified as the main landscape characteristic that was different between wintering habitat in Flores and Borneo. Savannah is well-known as a habitat for many species of amphibians, reptiles, and small mammals so that it can be a hunting area that provide alternative feed for OHBs.

Solvation free energies and partition coefficients with the coarse-grained and hybrid all-atom/coarse-grained MARTINI models.

Science.gov (United States)

Genheden, Samuel

2017-10-01

We present the estimation of solvation free energies of small solutes in water, n-octanol and hexane using molecular dynamics simulations with two MARTINI models at different resolutions, viz. the coarse-grained (CG) and the hybrid all-atom/coarse-grained (AA/CG) models. From these estimates, we also calculate the water/hexane and water/octanol partition coefficients. More than 150 small, organic molecules were selected from the Minnesota solvation database and parameterized in a semi-automatic fashion. Using either the CG or hybrid AA/CG models, we find considerable deviations between the estimated and experimental solvation free energies in all solvents with mean absolute deviations larger than 10 kJ/mol, although the correlation coefficient is between 0.55 and 0.75 and significant. There is also no difference between the results when using the non-polarizable and polarizable water model, although we identify some improvements when using the polarizable model with the AA/CG solutes. In contrast to the estimated solvation energies, the estimated partition coefficients are generally excellent with both the CG and hybrid AA/CG models, giving mean absolute deviations between 0.67 and 0.90 log units and correlation coefficients larger than 0.85. We analyze the error distribution further and suggest avenues for improvements.

Solvation free energies and partition coefficients with the coarse-grained and hybrid all-atom/coarse-grained MARTINI models

Science.gov (United States)

Genheden, Samuel

2017-10-01

We present the estimation of solvation free energies of small solutes in water, n-octanol and hexane using molecular dynamics simulations with two MARTINI models at different resolutions, viz. the coarse-grained (CG) and the hybrid all-atom/coarse-grained (AA/CG) models. From these estimates, we also calculate the water/hexane and water/octanol partition coefficients. More than 150 small, organic molecules were selected from the Minnesota solvation database and parameterized in a semi-automatic fashion. Using either the CG or hybrid AA/CG models, we find considerable deviations between the estimated and experimental solvation free energies in all solvents with mean absolute deviations larger than 10 kJ/mol, although the correlation coefficient is between 0.55 and 0.75 and significant. There is also no difference between the results when using the non-polarizable and polarizable water model, although we identify some improvements when using the polarizable model with the AA/CG solutes. In contrast to the estimated solvation energies, the estimated partition coefficients are generally excellent with both the CG and hybrid AA/CG models, giving mean absolute deviations between 0.67 and 0.90 log units and correlation coefficients larger than 0.85. We analyze the error distribution further and suggest avenues for improvements.

Grain-boundary engineering applied to grain growth in a high temperature material

International Nuclear Information System (INIS)

Huda, Z.

1993-01-01

Crystallography of grain boundaries are determined for a high temperature material, before and after grain growth processes, so as to study the induction of special properties useful for application in components of a gas-turbine engine. The philosophy of grain-boundary engineering is applied to grain growth in APK-6, a powder formed nickel-base superalloy so as to establish the possible structure/property relationships. The alloy in the as received condition is shown to possess a strong texture and contained coincident site lattices (CSL) boundaries with most boundaries having sigma values in the range of 3 > sigma > 25. A normal grain-growth heat treatment result in a good population of low angle grain boundaries, and drastically reduces the proportion of CSL boundaries. A strong [011] annealing texture is observed after an intermediate grain growth; most grain boundaries, here, tend to be high angle indicating a possibility of possessing special properties. (author)

Neural network classification technique and machine vision for bread crumb grain evaluation

Science.gov (United States)

Zayas, Inna Y.; Chung, O. K.; Caley, M.

1995-10-01

Bread crumb grain was studied to develop a model for pattern recognition of bread baked at Hard Winter Wheat Quality Laboratory (HWWQL), Grain Marketing and Production Research Center (GMPRC). Images of bread slices were acquired with a scanner in a 512 multiplied by 512 format. Subimages in the central part of the slices were evaluated by several features such as mean, determinant, eigen values, shape of a slice and other crumb features. Derived features were used to describe slices and loaves. Neural network programs of MATLAB package were used for data analysis. Learning vector quantization method and multivariate discriminant analysis were applied to bread slices from what of different sources. A training and test sets of different bread crumb texture classes were obtained. The ranking of subimages was well correlated with visual judgement. The performance of different models on slice recognition rate was studied to choose the best model. The recognition of classes created according to human judgement with image features was low. Recognition of arbitrarily created classes, according to porosity patterns, with several feature patterns was approximately 90%. Correlation coefficient was approximately 0.7 between slice shape features and loaf volume.

Grain Refinement of Freeform Fabricated Ti-6Al-4V Alloy Using Beam/Arc Modulation

Science.gov (United States)

Mitzner, Scott; Liu, Stephen; Domack, Marcia S.; Hafley, Robert A.

2012-01-01

Grain refinement can significantly improve the mechanical properties of freeform-fabricated Ti-6Al-4V alloy, promoting increased strength and enhanced isotropy compared with coarser grained material. Large beta-grains can lead to a segregated microstructure, in regard to both alpha-phase morphology and alpha-lath orientation. Beam modulation, which has been used in conventional fusion welding to promote grain refinement, is explored in this study for use in additive manufacturing processes including electron beam freeform fabrication (EBF(sup 3)) and gas-tungsten arc (GTA) deposition to alter solidification behavior and produce a refined microstructure. The dynamic molten pool size induced by beam modulation causes rapid heat flow variance and results in a more competitive grain growth environment, reducing grain size. Consequently, improved isotropy and strength can be achieved with relatively small adjustments to deposition parameters.

Barriers to wheelchair use in the winter.

Science.gov (United States)

Ripat, Jacquie D; Brown, Cara L; Ethans, Karen D

2015-06-01

To test the hypothesis that challenges to community participation posed by winter weather are greater for individuals who use scooters, manual and power wheelchairs (wheeled mobility devices [WMDs]) than for the general ambulatory population, and to determine what WMD users identify as the most salient environmental barriers to community participation during the winter. Cross-sectional survey organized around 5 environmental domains: technological, natural, physical, social/attitudinal, and policy. Urban community in Canada. Convenience sample of WMD users or their proxy (N=99). Not applicable. Not applicable. Forty-two percent identified reduced outing frequency in winter months, associated with increased age (χ(3)=6.4, P=.04), lack of access to family/friends for transportation (χ(2)=8.1, P=.04), and primary type of WMD used in the winter (scooter χ(2)=8.8, P=.003). Most reported tires/casters becoming stuck in the snow (95%) or slipping on the ice (91%), difficulty ascending inclines/ramps (92%), and cold hands while using controls or pushing rims (85%); fewer identified frozen wheelchair/scooter batteries, seat cushions/backrests, or electronics. Sidewalks/roads were reported to be problematic by 99%. Eighty percent reported needing additional help in the winter. Limited community access in winter led to a sense of loneliness/isolation, and fear/anxiety related to safety. Respondents identified policies that limited participation during winter. People who use WMDs decrease their community participation in cold weather because of multiple environmental barriers. Clinicians, researchers, and policymakers can take a multidimensional approach to mitigate these barriers in order to enhance community participation by WMD users in winter. Copyright © 2015 American Congress of Rehabilitation Medicine. Published by Elsevier Inc. All rights reserved.

AGA predicts winter jump in residential gas price

International Nuclear Information System (INIS)

Anon.

1992-01-01

The American Gas Association predicts the average heating bill for residential gas consumers could increase by as much as 18% this winter. AGA Pres. Mike Baly said, Last year's winter was warmer than normal. If the 1992-93 winter is similar, AGA projects that residential natural gas heating bills will go up about 6%. If we see a return to normal winter weather, our projection show the average bill could rise by almost 18%

Fine-Grained Turbidites: Facies, Attributes and Process Implications

Science.gov (United States)

Stow, Dorrik; Omoniyi, Bayonle

2016-04-01

Within turbidite systems, fine-grained sediments are still the poor relation and sport several contrasting facies models linked to process of deposition. These are volumetrically the dominant facies in deepwater and, from a resource perspective, they form important marginal and tight reservoirs, and have great potential for unconventional shale gas, source rocks and seals. They are also significant hosts of metals and rare earth elements. Based on a large number of studies of modern, ancient and subsurface systems, including 1000s of metres of section logging, we define the principal genetic elements of fine-grained deepwater facies, present a new synthesis of facies models and their sedimentary attributes. The principal architectural elements include: non-channelised slope-aprons, channel-fill, channel levee and overbank, turbidite lobes, mass-transport deposits, contourite drifts, basin sheets and drapes. These comprise a variable intercalation of fine-grained facies - thin-bedded and very thin-bedded turbidites, contourites, hemipelagites and pelagites - and associated coarse-grained facies. Characteristic attributes used to discriminate between these different elements are: facies and facies associations; sand-shale ratio, sand and shale geometry and dimensions, sand connectivity; sediment texture and small-scale sedimentary structures; sediment fabric and microfabric; and small-scale vertical sequences of bed thickness. To some extent, we can relate facies and attribute characteristics to different depositional environments. We identify four distinct facies models: (a) silt-laminated mud turbidites, (b) siliciclastic mud turbidites, (c) carbonate mud turbidites, (d) disorganized silty-mud turbidites, and (e) hemiturbidites. Within the grainsize-velocity matrix turbidite plot, these all fall within the region of mean size < 0.063mm, maximum grainsize (one percentile) <0.2mm, and depositional velocity 0.1-0.5 m/s. Silt-laminated turbidites and many mud

Selection of flooded agricultural fields and other landscapes by female northern pintails wintering in Tulare Basin, California

Science.gov (United States)

Fleskes, Joseph P.; Jarvis, Robert L.; Gilmer, David S.

2003-01-01

Habitat selection and use are measures of relative importance of habitats to wildlife and necessary information for effective wildlife conservation. To measure the relative importance of flooded agricultural fields and other landscapes to northern pintails (Anas acuta) wintering in Tulare Basin (TB), California, we radiotagged female pintails during late August-early October, 1991-1993 in TB and other San Joaquin Valley areas and determined use and selection of these TB landscapes through March each year. Availability of landscape and field types in TB changed within and among years. Pintail use and selection (based upon use-to-availability log ratios) of landscape and field types differed among seasons, years, and diel periods. Fields flooded after harvest and before planting (i.e., pre-irrigated) were the most available, used, and selected landscape type before the hunting season (Prehunt). Safflower was the most available, used, and-except in 1993, when pre-irrigated fallow was available-selected pre-irrigated field type during Prehunt. Pre-irrigated barley-wheat received 19-22% of use before hunting season, but selection varied greatly among years and diel periods. During and after hunting season, managed marsh was the most available, used, and, along with floodwater areas, selected landscape type; pre-irrigated cotton and alfalfa were the least selected field types and accounted for <13% of pintail use. Agricultural drainwater evaporation ponds, sewage treatment ponds, and reservoirs accounted for 42-48% of flooded landscape available but were little used and least selected. Exodus of pintails from TB coincided with drying of pre-irrigated fallow, safflower, and barley-wheat fields early in winter, indicating that preferred habitats were lacking in TB during late winter. Agriculture conservation programs could improve TB for pintails by increasing flooding of fallow and harvested safflower and grain fields. Conservation of remaining wetlands should concentrate

Phloem Transport of Arsenic Species from Flag Leaf to Grain During Grain Filling

Energy Technology Data Exchange (ETDEWEB)

A Carey; G Norton; C Deacon; K Scheckel; E Lombi; T Punshon; M Guerinot; A Lanzirotti; M Newville; et al.

2011-12-31

Strategies to reduce arsenic (As) in rice grain, below concentrations that represent a serious human health concern, require that the mechanisms of As accumulation within grain be established. Therefore, retranslocation of As species from flag leaves into filling rice grain was investigated. Arsenic species were delivered through cut flag leaves during grain fill. Spatial unloading within grains was investigated using synchrotron X-ray fluorescence (SXRF) microtomography. Additionally, the effect of germanic acid (a silicic acid analog) on grain As accumulation in arsenite-treated panicles was examined. Dimethylarsinic acid (DMA) and monomethylarsonic acid (MMA) were extremely efficiently retranslocated from flag leaves to rice grain; arsenate was poorly retranslocated, and was rapidly reduced to arsenite within flag leaves; arsenite displayed no retranslocation. Within grains, DMA rapidly dispersed while MMA and inorganic As remained close to the entry point. Germanic acid addition did not affect grain As in arsenite-treated panicles. Three-dimensional SXRF microtomography gave further information on arsenite localization in the ovular vascular trace (OVT) of rice grains. These results demonstrate that inorganic As is poorly remobilized, while organic species are readily remobilized, from leaves to grain. Stem translocation of inorganic As may not rely solely on silicic acid transporters.

Phloem transport of arsenic species from flag leaf to grain during grain filling

Energy Technology Data Exchange (ETDEWEB)

Carey, Anne-Marie; Norton, Gareth J.; Deacon, Claire; Scheckel, Kirk G.; Lombi, Enzo; Punshon, Tracy; Guerinot, Mary Lou; Lanzirotti, Antonio; Newville, Matt; Choi, Yongseong; Price, Adam H.; Meharg, Andrew A. (EPA); (U. South Australia); (Aberdeen); (UC); (Dartmouth)

2011-09-20

Strategies to reduce arsenic (As) in rice grain, below concentrations that represent a serious human health concern, require that the mechanisms of As accumulation within grain be established. Therefore, retranslocation of As species from flag leaves into filling rice grain was investigated. Arsenic species were delivered through cut flag leaves during grain fill. Spatial unloading within grains was investigated using synchrotron X-ray fluorescence (SXRF) microtomography. Additionally, the effect of germanic acid (a silicic acid analog) on grain As accumulation in arsenite-treated panicles was examined. Dimethylarsinic acid (DMA) and monomethylarsonic acid (MMA) were extremely efficiently retranslocated from flag leaves to rice grain; arsenate was poorly retranslocated, and was rapidly reduced to arsenite within flag leaves; arsenite displayed no retranslocation. Within grains, DMA rapidly dispersed while MMA and inorganic As remained close to the entry point. Germanic acid addition did not affect grain As in arsenite-treated panicles. Three-dimensional SXRF microtomography gave further information on arsenite localization in the ovular vascular trace (OVT) of rice grains. These results demonstrate that inorganic As is poorly remobilized, while organic species are readily remobilized, from leaves to grain. Stem translocation of inorganic As may not rely solely on silicic acid transporters.

Effects of coarse-graining on the scaling behavior of long-range correlated and anti-correlated signals.

Science.gov (United States)

Xu, Yinlin; Ma, Qianli D Y; Schmitt, Daniel T; Bernaola-Galván, Pedro; Ivanov, Plamen Ch

2011-11-01

We investigate how various coarse-graining (signal quantization) methods affect the scaling properties of long-range power-law correlated and anti-correlated signals, quantified by the detrended fluctuation analysis. Specifically, for coarse-graining in the magnitude of a signal, we consider (i) the Floor, (ii) the Symmetry and (iii) the Centro-Symmetry coarse-graining methods. We find that for anti-correlated signals coarse-graining in the magnitude leads to a crossover to random behavior at large scales, and that with increasing the width of the coarse-graining partition interval Δ, this crossover moves to intermediate and small scales. In contrast, the scaling of positively correlated signals is less affected by the coarse-graining, with no observable changes when Δ 1 a crossover appears at small scales and moves to intermediate and large scales with increasing Δ. For very rough coarse-graining (Δ > 3) based on the Floor and Symmetry methods, the position of the crossover stabilizes, in contrast to the Centro-Symmetry method where the crossover continuously moves across scales and leads to a random behavior at all scales; thus indicating a much stronger effect of the Centro-Symmetry compared to the Floor and the Symmetry method. For coarse-graining in time, where data points are averaged in non-overlapping time windows, we find that the scaling for both anti-correlated and positively correlated signals is practically preserved. The results of our simulations are useful for the correct interpretation of the correlation and scaling properties of symbolic sequences.

Ionizing radiation for insect control in grain and grain products

International Nuclear Information System (INIS)

Tilton, E.W.; Brower, J.H.

1987-01-01

A technical review summarizes and discusses information on various aspects of the use of ionizing radiation for the control of insect infestation in grains and grain products. Topics include: the effects of ionizing radiation on insects infesting stored-grain products; the 2 main types of irradiators (electron accelerators; radioisotopes (e.g.: Co-60; Cs-137); dosimetry systems and methodology; variations in radiation resistance by stored-product pests; the proper selection of radiation dose; the effects of combining various treatments (temperature, infrared/microwave radiation, hypoxia, chemicals) with ionizing radiation; sublethal radiation for controlling bulk grain insects; the feeding capacity of irradiated insects; the susceptibility of insecticide-resistant insects to ionizing radiation; and the possible resistance of insects to ionizing radiation. Practical aspects of removing insects from irradiated grain also are discussed

Seasonal prediction skill of winter temperature over North India

Science.gov (United States)

Tiwari, P. R.; Kar, S. C.; Mohanty, U. C.; Dey, S.; Kumari, S.; Sinha, P.

2016-04-01

The climatology, amplitude error, phase error, and mean square skill score (MSSS) of temperature predictions from five different state-of-the-art general circulation models (GCMs) have been examined for the winter (December-January-February) seasons over North India. In this region, temperature variability affects the phenological development processes of wheat crops and the grain yield. The GCM forecasts of temperature for a whole season issued in November from various organizations are compared with observed gridded temperature data obtained from the India Meteorological Department (IMD) for the period 1982-2009. The MSSS indicates that the models have skills of varying degrees. Predictions of maximum and minimum temperature obtained from the National Centers for Environmental Prediction (NCEP) climate forecast system model (NCEP_CFSv2) are compared with station level observations from the Snow and Avalanche Study Establishment (SASE). It has been found that when the model temperatures are corrected to account the bias in the model and actual orography, the predictions are able to delineate the observed trend compared to the trend without orography correction.

White Sea's Severe Winter Hydrological Hazard and Its Effect On Decrease of Population of Greenland Seals (1998/99 Winter Ecological Catastrophe)

Science.gov (United States)

Melentyev, Konstantin V.; Chernook, Vladimir I.

Types of hydrological hazards are various but its agencies are especially diversified . At this study hazard effects will be assessed for White Sea population of Greenland seals - a representatives of high level of marine fodder chains and the prime part of the Arctic nature. Number of population and type of their migration are strongly depended from different meteorological and hydrological parameters and processes, climate change and anthropogenical press, including pollution and fur-seal fishery, create additional problems. Especially hard situation happens now with the ice- associated sea mammals (p olar bear, seal, walrus, etc.). Mass destruction of seals in the White Sea (ecological catastrophe) which happens periodically is close connected with different kind of meteorological and hydrological hazard. Greenland seals selected these water areas for whelping where a rookeries are organized on pack ice. But severe winter conditions (long-run severe frosts and NE winds) can modify ice regime of the White Sea which lead to effect "blocking" of pack ice (and whelping rookeries) inside the "Basin". These features stimulated strong reduction number ofseals (especially pups). Marine biology use modelling of the system "sea mammal-media", study "behavior factors" and mammals biodiversity at the different natural conditions. But the main critical goal is the development of special observational network for the White Sea and contiguous regions. A contemporary technologies assume integration of remote sensing and in situ hydro-chemical measurements. Airborne IR and visible observation of the marginal Arctic seas became now an indispensable part of marine ecological investigations. Application of satellite data for monitoring of sea mammals has been attractive also but practical use is restrained by its small spatial resolution, daytime illumination and cloud influence in the Arctic. Launching ERS synthetic aperture radar (SAR) in 1991, which provides global all- weather

Stress-assisted grain growth in nanocrystalline metals: Grain boundary mediated mechanisms and stabilization through alloying

International Nuclear Information System (INIS)

Zhang, Yang; Tucker, Garritt J.; Trelewicz, Jason R.

2017-01-01

The mechanisms of stress-assisted grain growth are explored using molecular dynamics simulations of nanoindentation in nanocrystalline Ni and Ni-1 at.% P as a function of grain size and deformation temperature. Grain coalescence is primarily confined to the high stress region beneath the simulated indentation zone in nanocrystalline Ni with a grain size of 3 nm. Grain orientation and atomic displacement vector mapping demonstrates that coalescence transpires through grain rotation and grain boundary migration, which are manifested in the grain interior and grain boundary components of the average microrotation. A doubling of the grain size to 6 nm and addition of 1 at.% P eliminates stress-assisted grain growth in Ni. In the absence of grain coalescence, deformation is accommodated by grain boundary-mediated dislocation plasticity and thermally activated in pure nanocrystalline Ni. By adding solute to the grain boundaries, the temperature-dependent deformation behavior observed in both the lattice and grain boundaries inverts, indicating that the individual processes of dislocation and grain boundary plasticity will exhibit different activity based on boundary chemistry and deformation temperature.

Hormonal changes in the grains of rice subjected to water stress during grain filling.

Science.gov (United States)

Yang, J; Zhang, J; Wang, Z; Zhu, Q; Wang, W

2001-09-01

Lodging-resistant rice (Oryza sativa) cultivars usually show slow grain filling when nitrogen is applied in large amounts. This study investigated the possibility that a hormonal change may mediate the effect of water deficit that enhances whole plant senescence and speeds up grain filling. Two rice cultivars showing high lodging resistance and slow grain filling were field grown and applied with either normal or high amount nitrogen (HN) at heading. Well-watered and water-stressed (WS) treatments were imposed 9 days post anthesis to maturity. Results showed that WS increased partitioning of fixed (14)CO(2) into grains, accelerated the grain filling rate but shortened the grain filling period, whereas the HN did the opposite way. Cytokinin (zeatin + zeatin riboside) and indole-3-acetic acid contents in the grains transiently increased at early filling stage and WS treatments hastened their declines at the late grain filling stage. Gibberellins (GAs; GA(1) + GA(4)) in the grains were also high at early grain filling but HN enhanced, whereas WS substantially reduced, its accumulation. Opposite to GAs, abscisic acid (ABA) in the grains was low at early grain filling but WS remarkably enhanced its accumulation. The peak values of ABA were significantly correlated with the maximum grain filling rates (r = 0.92**, P water stress during grain filling, especially a decrease in GAs and an increase in ABA, enhances the remobilization of prestored carbon to the grains and accelerates the grain filling rate.

MAGNETIC GRAIN TRAPPING AND THE HOT EXCESSES AROUND EARLY-TYPE STARS

Energy Technology Data Exchange (ETDEWEB)

Rieke, G. H.; Gáspár, András; Ballering, N. P., E-mail: grieke@as.arizona.edu, E-mail: agaspar@as.arizona.edu, E-mail: ballerin@email.arizona.edu [Steward Observatory, University of Arizona, Tucson, AZ 85721 (United States)

2016-01-10

A significant fraction of main sequence stars observed interferometrically in the near-infrared have slightly extended components that have been attributed to very hot dust. To match the spectrum appears to require the presence of large numbers of very small (<200 nm in radius) dust grains. However, particularly for the hotter stars, it has been unclear how such grains can be retained close to the star against radiation pressure force. We find that the expected weak stellar magnetic fields are sufficient to trap nm-sized dust grains in epicyclic orbits for a few weeks or longer, sufficient to account for the hot excess emission. Our models provide a natural explanation for the requirement that the hot excess dust grains be smaller than 200 nm. They also suggest that magnetic trapping is more effective for rapidly rotating stars, consistent with the average vsini measurements of stars with hot excesses being larger (at ∼2σ) than those for stars without such excesses.