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Climate warming may change soil nutrient supply and affect the biogeochemical processes, especially the nitrogen (N) cycle in forest ecosystems. However, little is still known about how root N uptake responds to climate warming, and whether forests will experience more intense N limitation under warming. We studied the N absorption and mycorrhizal infection rate in the roots of seedlings of a subalpine coniferous species, Picea asperata Mast., under experimental warming, four years after the seedlings were transplanted in the experimental plots. We found that warming had a significant positive effect on root N absorption, with increases of 151.1%, 99.6%, and 71.9% in May, July, and October of 2011, respectively, when compared to the control treatment. In addition, warming increased the N element content and reduced the C:N ratio of the roots over the warming period. Warming also increased mycorrhizal infections by 30.5%, 12.3%, and 108.1% in May, July, and October of 2011, respectively, when compa...

This study was designed to evaluate the effect of inorganic and organic fertilizers on banana fruiting, as well as its effect on edaphic macro fauna in banana cultivars in Ecuador. In this study, Dwarf Curaré variety meristematic banana plants were used with different inorganic fertilizers included: CH 4 N 2 O, KCl, (NH 4) 2 HPO 4 , CaH 4P2O8 , K, Mg. Organic solid fertilizers were used as a counterpart. The treatments used to be: (T1) without nitrogen fertilization; (T2) 60; (T3) 120; (T4) 180; (T5) with 240 kg ha-1 of N respectively; (T6, T7, T8) with 1, 2 and 3 kg of organic solid fertilizer per plant1; (T9) mix of T3+T6; (T10) mix of T2+T7. It was found that the application of nitrogen reduced the flowering time by 35 days. Also, it was noted that the use of organic nitrogen did not have the same effect as inorganic nitrogen on fruiting and finally nitrogen accumulation in bunches and fruits. The application of organic and inorganic fertilizers, did not affect the biomass of organisms in the soil

Nitrogen content of the high-pressure bottle steel was high and with big fluctuation, it is difficult to control. SO, investigation on nitrogen content of the all steelmaking process is carried out. Results of the investigation indicated that nitrogen content of the aimed steel was high, nitrogen absorption was mainly happened during tapping and in the course of after refining to before casting。And then nitrogen control measures such as low-nitrogen steel melting technology, optimization of deoxidization, protective casting technology is raised. After that nitrogen content of the aimed steel was reduced and nitrogen absorption during tapping and in the course of after refining to before casting was effectively controlled, nitrogen content of the finished steel was stably controlled in 50×10-6, the effect of nitrogen on property of steel is reduced.

For growth in the aquaculture sector to be sustainable in the long term, there is a critical need to make operations more efficient through effective disease control management and with optimized (and stage specific) feeds and improved feed conversion ratios. An enhanced level of integration spanning from breeding centres, to hatcheries, to nurseries and farm production is a pre-requisite for growth.Synthetic compounds use in aquaculture has created resistant bacteria, immune-suppression and destabilization of helpful bacterial population as well as environmental pollution. To replace their effects, the search for natural alternatives has begun. Through natural compound use it can be hoped to achieve the same results as in the use of synthetic compounds. The present study is a review of the use of some natural substances and of the researches made to reveal their effects on fish. Research have shown the diverse effects of these natural compounds used in fish as immune-modulators, immune-stimulants, bio-productive, antioxidants, antimicrobials, stimulants of the enzymatic equipment, stimulants of nitrogen absorption. A major advantage in the use of natural compounds is the fact that they are natural substances and do not pose any threat to fish, man or environment.

The results of measuring the temperature dependences of the kinematic viscosity and electrical resistivity of liquid lanthanum and aluminum are reported. Taking into account the data on the viscosity, electrical resistivity, surface tension, metallochemical properties of these elements, and the results of physicochemical analysis, conditions for the synthesis of powders of the elements are determined. Isotherms of lowtemperature physical nitrogen absorption on the surface of ultrafine-grained Al-La powders are measured, and data on their specific surface are obtained.

Background: Pancreatic enzyme replacement therapy (PERT) is used to treat exocrine pancreatic insufficiency in cystic fibrosis. Results/Methods: Efficacy and safety of a unique enteric-coated (EC) bicarbonate-buffered PERT product (PERTZYE®/PANCRECARB®; Digestive Care, Inc., Bethlehem, PA, USA) was studied in a randomized, double-blind, placebo-controlled cross-over design. Subjects were stabilized on EC-bicarbonate-buffered PERT and a high-fat diet. During two treatment periods, subjects were randomized to EC-bicarbonate-buffered PERT or placebo, followed by a 72-h stool collection employing an ingested stool dye marker. Mean coefficient of fat absorption with EC-bicarbonate-buffered PERT was 82.5% compared with 46.3% with the placebo (absolute difference 36.2%; p < 0.001), a 78.2% improvement for active over placebo. Similar improvements in nitrogen absorption were observed. Overall stool frequency and stool weight decreased (p < 0.001). No safety concerns were identified. Summary: EC-bicarbonate-buffer...

As shrinkage in concrete leading to the subsequent cracking and reducing durability, the study on shrinkage is quite important. Based on microstructure of pores obtained from Nitrogen absorption method and mechanical testing, a numerical shrinkage model was built. The standard shrinkage test results show consistent in the blended cement pastes with different water-to-cement ratioand admixture content to predict shrinkage values, which confirmes the shrinkage model based upon microstructure of blended cement pastes.

This chapter discusses the growth, nitrogen absorption/distribution, and physiological responses of Salix matsudana seedlings cultured in hydroponic solution with different nitrogen sources ammonium nitrogen (\( {{{\text{NH}}_{4}}^{ + }} \)–N) or nitrate nitrogen (\( {{{\text{NO}}_{3}}^{ - }} \)–N)); inadequate, medium, high, or excessive nitrogen. Results showed that S. matsudana biomass increased with increasing nitrogen concentration to a certain extent. S. matsudana growth was inhibited by excessive nitrogen concentration, and the inhibition rate of \( {{{\text{NH}}_{4}}^{ + }} \)–N was higher than that of \( {{{\text{NO}}_{3}}^{ - }} \)–N. S. matsudana showed absorption preference toward \( {{{\text{NH}}_{4}}^{ + }} \)–N than \( {{{\text{NO}}_{3}}^{ - }} \)–N under the same nitrogen concentration. at.% content, 15N absorption, and Ndff% exhibited the following trend in different organs of S. matsudana: root > stem > leaf. Moreover, \( {{{\text{NH}}_{4}}^{ + }} \)–N content was higher than that of \( {{{\text{NO}}_{3}}^{ - }} \)–N, and the difference intensified with increasing nitrogen concentration. Excessive and inadequate nitrogen concentrations of \( {{{\text{NH}}_{4}}^{ + }} \)–N and \( {{{\text{NO}}_{3}}^{ - }} \)–N exerted different effects on physiological parameters in roots and leaves. Root activity under excessive concentrations of \( {{{\text{NH}}_{4}}^{ + }} \)–N and \( {{{\text{NO}}_{3}}^{ - }} \)–N decreased by 50.61 % and increased by 19.53 %, respectively, compared with that of the control group. Root length, root surface area, average root diameter, root volume, and root tips were lower by 30.92, 29.48, 19.44, 27.01 and 36.41 %, respectively, in \( {{{\text{NH}}_{4}}^{ + }} \)–N treatment and by 1.66, 5.65, 1.49, 5.06, and 25.72 %, respectively, in \( {{{\text{NO}}_{3}}^{ - }} \)–N treatment than those in the control group. This result indicated that high \( {{{\text{NH}}_{4}}^{ + }} \)–N concentrations elicited stronger stress effect on S. matsudana than \( {{{\text{NO}}_{3}}^{ - }} \)–N. Therefore, the effect of \( {{{\text{NH}}_{4}}^{ + }} \)–N on S. matsudana could be alleviated to some extent by adding \( {{{\text{NO}}_{3}}^{ - }} \)–N to improve the remediation of water polluted by nitrogen.

In this study, we assessed the N and P absorption of 2 Salix integra clones in artificial eutrophicated water based on the method of pot experiment, and further conducted the study on \( {{{\text{NH}}_{4}}^{ + }} \)–N and \( {{{\text{NO}}_{3}}^{ - }} \)–N uptake kinetics. The results showed that 2 Salix integra clones could effectively remove TN (90 %) at the treatment level of low concentrations, which was 2 times as that of high concentrations treatment. While for removal efficiency of total phosphorus (TP), at the treatment level of low concentrations it reached 80 %, and then at high concentrations it attained 90 %. The order of removal efficiency was S. integra “Yizhibi” > S. integra “Weishanhu.” Moreover, the removal efficiency of \( {{{\text{NH}}_{4}}^{ + }} \)–N and \( {{{\text{NO}}_{3}}^{ - }} \)–N was both increased as the concentration changed. For the maximum absorption efficiency and affinity, generally speaking, S. integra “Weishanhu” was greater than S. integra “Yizhibi” in the state of single N source. However, when the other N source existed, the maximum absorption efficiency would fall down to 50 %.

The phase structure and magnetic were investigated by means of x-ray diffraction and differential thermal /thermogravimetric analyzer. The result showed that nitrogenized reaction started at 140oC with little nitrogen diffused into Tm2CrFe13Si3 compound. The nitrogen absorption of the Tm2CrFe13Si3 compound was most violent at 700oC, and its Curie temperature TC increased obviously. As the temperature increased continually, part of the Tm2CrFe13Si3 compound decomposed into TmN compound and α-Fe.

The effects of the waterworks sludge as cultivation substrate on the properties of substrate and the growth of potted flowers—Globe amaranth were studied. The results showed that the waterworks sludge as cultivation substrate could promote the growth of Globe amaranth in height, leaf length, fresh weight, and the TN, TP, TK content in the stems and leaves. Compared to the control groups without waterworks sludge, waterworks sludge could improve the physicochemical properties of the substrate; promote the nitrogen absorption for the Globe amaranth, and improve its ornamental value. So, waterworks sludge had certain advantage as a new cultivation substrate.

Sm-Fe-N was prepared by melt-spun Sm-Fe with liquid-N2-cooled copper wheel and nitrogen absorption under N2 gas pressures up to 25 MPa. The structure and magnetic properties of the Sm-Fe-N prepared under varied temperatures, N2 pressures and nitrogen absorption time have been investigated systematically. The liquid N2 melt-spun process improves the homogeneity of the samples while the high N2 pressure increases the efficiency of the nitrogenation process. The Sm-Fe-N decomposes under 25 MPa N2 at temperatures above 743 K.

Application with 50 mg L−1 5-aminolevulinic acid (5-ALA) to pakchoi (Brassica campestris ssp. chinensis var. communis Tsen et Lee) seedlings showed that when seedlings were cultured in 1/2 Hoagland's solution containing 1/2 of standard (3.75 mmol L−1) or standard nitrate (7.5 mmol L−1), the outer leaves of rosette plants gradually turned yellow, whereas much fewer yellowed leaves were found when 5-ALA was added. Analysis showed that 5-ALA treatment increased the leaf chlorophyll content, root activities, and insomuch plant production. 5-ALA treatment also greatly increased the content of free amino acids and soluble proteins. However, 5-ALA treatment decreased nitrate accumulation in both leaf blades and petioles, which was related with higher activity of nitrate reductase (NR) and higher level of NR gene transcript in pakchoi leaves. These results suggest that exogenous 5-ALA treatment may promote nitrogen absorption and assimilation with less nitrate accumulation in leaf tissues.

Dois experimentos foram realizados para avaliar a influência de duas porcentagens de lisina associada à restrição alimentar sobre o desempenho e balanço de nitrogênio de suínos em terminação. No experimento I, foram utilizados 48 suínos machos castrados, com média de peso de 76,2±2,3kg, distribuídos em delineamento em blocos ao acaso, em esquema fatorial 2x2 (duas porcentagens de lisina total - normal ou com 30% a mais - e duas formas de arraçoamento - à vontade ou com restrição). Com 28 dias, a porcentagem de inclusão de lisina não influenciou o ganho de peso, mas a porcentagem mais alta resultou em menor consumo e melhor conversão alimentar. A restrição alimentar diminuiu o ganho de peso sem afetar a conversão alimentar. No experimento II, 24 suínos machos castrados, com média de peso de 74,1±2,5kg, foram alojados em gaiolas de metabolismo para receber os mesmos tratamentos. Aos 14 dias de experimento, as dietas não influenciaram a absorção de nitrogênio e a ureia plasmática, porém a dieta ad libitum com a maior porcentagem de lisina reduziu a retenção de nitrogênio. Aos 28 dias, essa mesma dieta aumentou a concentração de ureia plasmática. Conclui-se que o aumento da lisina nas rações melhora o desempenho de suínos machos castrados em terminação, independentemente da forma de arraçoamento, e que a restrição alimentar, nesta fase, não é benéfica. Two experiments were led to evaluate the influence of two percentages of lysine associated to feed restriction over performance and nitrogen balance of finishing barrows. In experiment I, 48 barrows were used, weighing 76.2±2.3kg, distributed in a randomized blocks design in factorial scheme 2x2 (two levels of total lysine - normal or added in 30% - and two feed programs - restricted or ad libitum). At 28 days, the levels of lysine did not influence weight gain, but the higher level provided lesser feed intake and better feed:gain. The feed restriction decreased the weight gain without affecting feed:gain. In Experiment II, 24 barrows, weighing 74.1±2.5kg, were put in metabolic cages to receive the same previously described treatments. At 14 days of the experiment, the diets did not influence the nitrogen absorption and the plasmatic urea, however, the ad libitum diet associated at the higher lysine level reduced nitrogen retention. At 28 days, this same diet increased the plasmatic urea concentration. It was concluded that the increase of lysine levels in diets improves performance in finishing barrows, regardless of the feed program, and feed restriction, in this phase, is not beneficial.

The experiment studied the influence of slag system on nitrogen content in high nitrogen steels which refined by the method of high-pressure and bottom-blowing nitrogen under the conditions of 1.0Mpa. The results shows that nitrogen content are up to 1.0% without the over of slag, and after adding slag, nitrogen content are up to 1.39%; Alkalinity of protecting slag has little effect on the nitrogen content, however, there are very effective to increase nitrogen after using CaF2 instead of SiO2 ,and its nitrogen content are as high as 1.48%; the effect of increasing nitrogen are clear by adding no more than 0.5% pure aluminum, but when aluminum content are more than 0.5%, the nitrogen content in steel are not change significantly, meanwhile, if adding CaF2 slag system, it will be more effective increase nitrogen than only adding pure aluminum.

A series of hydrotalcite-derived mixed oxides containing different organic interlayer anions in the hydrotalcite precursors have been synthesized and studied as catalysts in the transesterification of glycerol trioctanoate with methanol. There are significant differences in the catalytic activity of these mixed oxides, indicating a great impact of interlayer anions in hydrotalcite precursors. Generally, anions with high charge density and, therefore, high content within the interlayer of the hydrotalcites lead to higher catalytic activity in the derived mixed oxides in contrast to anions with low charge density. An influence of interlayer anions on the structural properties of the hydrotalcites, such as interlayer distance, which is determined by X-ray diffraction analysis, and on the surface area and pore volume of the corresponding mixed oxides, which are determined by nitrogen absorption, is obtained. Furthermore, interlayer anions had a significant effect on the thermal stability of the hydrotalcite structure as well as on the pore size distribution of derived mixed oxides.

We analysed stability and predictive capabilities of known nitrogen absorption features between plant material prepared for NIRS (dried) and RS (fresh) studies. Grass spectra were taken of the plant canopy, and again after the grass sample was dried and ground. Models were derived using stepwise multiple linear regression (sMLR). Regression values (adj.r2) produced using the dried material were greater than those produced using canopy material. For dried material only wavebands from the SWIR region were selected. Wavebands selected by sMLR on canopy material were located in both the VNIR and SWIR regions. Using wavebands selected for dried material models produced low adj.r2 values when applied to canopy plant material; differences in adj.r2 values are smaller when wavebands selected in canopy material models are applied to dried material. Widening of nitrogen features produced higher adj.r2 values for both dried and canopy material. This work shows that obtaining models with high predictive capabilities for nitrogen concentration is possible, but waveband selection should not be limited to features identified by NIRS studies. To accommodate for variability in absorption features, and instrument errors, absorption features should be widened.

Zusammenfassung Die Ammoniak-, Harnstoff-, Glutamat- und Glutaminkonzentrationen in der V. portae und der V. jugularis bei Schafen wurden in zwei Futterungsperioden — mit bzw. ohne Harnstoffzusatz — bestimmt. Gleichzeitig wurde der Blutdurchflus durch die V. portae mit elektromagnetischen Blutstromungsaufnehmern fortlaufend registriert. Aus den porto-jugularen Konzentrationsdifferenzen und dem Blutdurchflus waren quantitative Ruckschlusse auf die Resorption von Ammoniak und Glutamat aus dem Intestinaltrakt moglich. Das Maximum der Ammoniakresorption betrug 1.8 mmol/kg KGW/h bei Harnstoffzusatz und 1.15 mmol/kg KGW/h ohne Harnstoffzusatz. Die durchschnittliche tagliche Ammoniakresorption ist bei einem 50-kg-Schaf mit 8.5 g bzw. 13.0 g ohne bzw. mit Harnstoffutterung anzusetzen. Der Anteil des in Form des Glutamats resorbierten Ammoniaks liegt unter 10%. Diese Transportform des Ammoniaks ist bei vermehrter Ammoniakanflutung rasch gesattigt. Das Glutamin scheint beim Transport des Ammoniaks aus dem Intestinaltrakt zur Leber keine Rolle zu spielen.

The aim of this work is to construct a periodic compartmental model of the nitrogen dynamics in young evergreen trees based on the kinetic description of nitrogen absorption, distribution and mobilization in each organ. It considers each tissue type as source and sink for nitrogen and uses flow equations to simulate the dynamics of nitrogen partitioning during an annual cycle. This model will be used to get information that may improve the criteria that are followed in the nitrogen fertilization of citrus at present.

The central origin of the potato (Solanum tuberosum) is Lake Titicaca of the central Andean highlands. People living in the Andean mountains utilize potato for staple food from ancient times. According to the previous studies, the distribution of the wild species related with the cultivars is human- induced environment such as roadside, cultivated fields, Inca ruins and garbage dumps. However, the mankind marched to the Andean mountains before approximately 10 thousand years. Before mankind's arrivals, the wild species of potato grew in the Andean mountains. We focus on the dung piles of vicuña (Vicugna vicugna) of Camelidae animal for the gene cradles for Solanum species. One of the wild species, Solanum acaule, establishes the colonies at the dung piles of vicuña. They absorb the nitrogen from the abundant soil nutrients of the dung piles for both vegetative and seed reproduction. The tuber growth of the Solanum cultivar is related with the rich nutrition use of the wild species growing in the dung piles of Camelidae animals.

Two varieties of wheat plants, i.e., Acsad 65 and Cham 3 were cultivated inDeirezzor to Governorate study effect of applied different rates of nitrogen fertilizer onthe chemical and fertility properties of soil as well as the economical return of thestudied two grown varieties.The obtained results showed that applying mineral fertilizer gaves areal increasein the wheat yield, while this didn't occur when phosphorus was applied alone. Also,increasing the rate of nitrogen fertilizer within the complete fertilization equation gave areal increase increment in wheat yield reached of about 310.08 kg/donum in case ofCham-3 as compared to the control treatment, while increasing nitrogen fertilizer rateover the optimal limits didn't give any real increase in both of the studied wheatvarieties.Response of Cham-3 to the increase of nitrogen fertilizer rates was clearly obviousthan of Acsad-65, as shown in treatment -3, where yield of Sham-3 reached 460.93kg/donum.It is noteworthy to mention that available nitrogen in the experimental soilincreased with increasing the applied nitrogen fertilizer rates, the reverse was true foravailable phosphor, however its amount decreased with increasing nitrogen fertilizerrates within the fertilizer equation.

Scarcity of water and N fertilizer are major constraints to rice production, particularly in developing countries where rainfed upland condition dominates. Improvement of genetic adaptability to inadequate water and N fertilizer is one option to maintain productivity in these regions. NERICAs are expected to yield higher under low input conditions, but growth and yield responses of the cultivars to different ecosystems and N levels remain unknown. The objectives of this study were to characterize the growth and yield performance of NERICAs, in comparison with selected Japanese rice cultivars. The two NERICAs (NERICA 1 and NERICA 5), two Japanese upland cultivars (Toyohatamochi and Yumenohatamochi), and a Japanese lowland cultivar Hitomebore were grown under two ecosystems (irrigated lowland (IL) and rainfed upland (RU)) with two N levels (high (H) and low (L)) for two years. The cultivar difference in the aboveground dry weight and grain yield was the largest in the in RU × L plot, where the values of NERICAs were similar to those in the other plots, but the values of other cultivars were substantially reduced. Regardless of cultivar, N contents of the plants at maturity correlated significantly with the aboveground dry weight at maturity, spikelet number and grain yield per area. These results indicate that NERICAs, compared with the selected Japanese upland cultivars that were bred for drought tolerance, have a higher ability to absorb N under upland conditions, which may contribute to higher biomass production and sink formation, resulting in increased gain yield.

A two-band digital imaging system —one band for the visible red band (RED, 630−670 nm) and the other for the near infrared band (NIR, 820−900 nm)— was devised and positioned at a height of 12 m above a rice field of 300 m2 in area during the 2007 growing season. The imaging system automatically logged bird’seye view images at 10-min intervals from 0800−1600 every day. Radiometric corrections for the pairs of two-band images were done using solar irradiance sensors and preceding calibrations to calculate daily band-reflectance and the normalized difference vegetation index (NDVI) values for 9 plots of rice plants, with 3 levels of planting density and basal fertilization. The daily- averaged reflectance values in the RED and the NIR bands showed different but smooth seasonal changing patterns according to the growth of plants. At the maximum tiller number and the panicle formation stages, the RED and NIR reflectance values had correlation coefficients (r) of 0.79 and 0.81 with above-ground nitrogen absorption per unit land area (NA, g m-2), respectively, whereas the NDVI using the two band reflectance values showed r-value of -0.13. An empirically derived equation for the NA using two band reflectance values showed r-value of 0.96 and a root mean square of error (RMSE) 0.5 g m–2 (10% of the mean observed NA) in the estimation for the original (not validated) data set acquired at the maximum tiller number and the panicle formation stages. The results indicated that reflectance observation in the RED and NIR bands using the digital imaging system was potentially effective for assessing rice growth.

Electron microscopy, X-ray diffraction analysis, and low-temperature nitrogen absorption are used to study the size characteristics of a nickel nanopowder. An interrelation between the size parameters of the nanomaterial (aggregates, particles, and crystallites) is found to exist. All these characteristics are shown to be true and to have a physical and technological meaning.

Summary • Close correlations between specific leaf area (SLA) and relative growth rate (RGR) have been reported in many studies. However, theoretically, SLA by itself has small net positive effect on RGR because any increase in SLA inevitably causes a decrease in area‐based leaf nitrogen concentration (LNCa), another RGR component. It was hypothesized that, for a correlation between SLA and RGR, SLA needs to be associated with specific nitrogen absorption rate of roots (SAR), which counteracts the negative effect of SLA on LNCa.• Five trees and six herbs were grown under optimal conditions and relationships between SAR and RGR components were analyzed using a model based on balanced growth hypothesis.• SLA varied 1.9‐fold between species. Simulations predicted that, if SAR is not associated with SLA, this variation in SLA would cause a 47% decrease in LNCa along the SLA gradient, leading to a marginal net positive effect on RGR. In reality, SAR was positively related to SLA, showing a 3.9‐fold variation, which largely compensated for the negative effect of SLA on LNCa. Consequently, LNCa values were almost constant across species and a positive SLA–RGR relationship was achieved.• These results highlight the importance of leaf–root interactions in understanding interspecific differences in RGR.

Three variants of the empirical molecular MT-potential of different types of complexity are constructed based on the analysis of the K-spectrum of nitrogen absorption in NO2 molecule. It is shown that the variant with the Watson sphere is the most realistic model. In the variants with the zero external molecular potential the intra-atomic potentials to a greater or lesser extent do not satisfy the physical criteria.

BACKGROUND We sought to compare the differences of coefficient of fat absorption (CFA) and coefficient of nitrogen absorption (CNA) in healthy individuals and those with cystic fibrosis (CF) and to study the precision of CFA and CNA.METHODS Sixteen healthy and 23 subjects with CF and pancreatic insufficiency ate a high-fat, high-protein diet for 72 hours; stool was collected between blue food dye markers to determine CFA and CNA. Subjects with CF withheld pancreatic enzymes. Tests were repeated on 5 of the CF and 10 of the healthy subjects.RESULTS In healthy subjects, mean CFA was 93.5% ± 2.7%; mean CNA was 88.1% ± 5%. Median test-retest in 10 healthy subjects was +0.7% CFA (range, −8.1% to + 5.9%) and +0.9% CNA (range, −14.6% to +6.8%). For subjects with CF, mean CFA was 38.5% ± 14.7% and mean CNA was 52.2% ± 11.4%. Median test-retest change in 5 subjects with CF was −6.9% CFA (range, −19.7% to +42.8%) and +14.7% CNA (range, −6.4% to +42.8%).CONCLUSIONS CFA and CNA have inconsistent precision in CF. The limitations of CFA as a measure of steatorrhea correction in CF should be recognized in studies of pancreatic enzyme supplements.

Plants require nitrogen (N) within the soil to produce high yields. However, the transport mechanism of nutrients from root medium to plant and the response of plant nitrogen tissue to nitrogen uptake have not been identified so far. The experiments in this study were performed in summer of 2005 and 2006 in order to define the mechanism of nutrient uptake and specify the response of plant nutrient content in Phragmites japonica. The results suggest that the mayor part of nitrogen absorption is due to an active uptake process. The influx is subject to negative feedback on high external concentration and reaches a maximum uptake rate after 6-8 hours of exposure. The response of leaf N content to NO3 - uptake not only proves the uptake process based on plant demand but also appears to be independent with external concentration and uptake rate. The results also imply the fact that plants may have sufficient capacity to store nutrients.

The practices of nitrogen fertilization are really changing, due to the new farming context including environmental, economical, and energetic constraints. In 2005, 90% of the producers said they used a method to adapt nitrogen supplies in their fields and more than 40% among them used the CETIOM method “réglette azote”. Since 2004, a new system, called Farmstar-colza® based on satellite observation has been developed by Infoterra France, a subsidiary of the EADS group. With this technology, it’s possible to draw a map of the fields with nitrogen supply advices and to practice modular apply on the crops. Moreover, this technology increases the precision of the crop nitrogen absorption assessment. Therefore, in the future it seems possible to improve the estimated need of nitrogen to grow oil seed rape in order to get a good energetic balance with an optimum oil rate as well as high yields.

To examine the possibility of breeding higher-yielding cultivars with a high nitrogen use efficiency (NUE) and to provide simple criteria for the selection and breeding of high-yielding cultivars with a high NUE and useful information for the mapping of quantitative trait loci (QTL) controlling NUE, recombinant inbred lines (RILs) of rice were subjected to hydroponic culture in 2000 and 2001. Grain yield and yield components, total nitrogen absorption (NTA), pre-heading and post-heading nitrogen absorption (pre-NA and post-NA, respectively), and nitrogen use efficiency for grain yield (NUEg) were analyzed. Transgressive segregations for grain yield and yield components, NTA and NUEg were observed. RILs with a high grain yield tended to show a larger number of panicles m−2 and of spikelets per panicle, and a higher filled grain percentage than RILs with a low grain yield. Increasing NTA and NUEg resulted in increases in the number of spikelets m−2 and grain yield, while increasing NTA resulted in ...

Ingots of ferritic stainless steels, Fe-24Cr-2Mo in mass%, were worked to various dimensions for test specimens. Nitrogen was absorbed by the specimens in a furnace filled with nitrogen gas with a pressure of 101.3 kPa at 1473 K to develop a simple and convenient manufacturing process of nickel-free austenitic stainless steels. Changes in the mechanical properties of the alloy with nitrogen absorption treatment are discussed on the basis of the resultant microstructure. Ferritic Fe-24Cr-2Mo was austenitized with 129.6-ks nitrogen absorption to a 2-mm depth from the surface. On the other hand, Fe-24Cr-2Mo was completely austenitized with 7.2-ks nitrogen absorption to a 0.5-mm depth from the surface. The hardness, tensile strength, 0.2% proof stress, and elongation to fracture increased, and the reduction of area decreased in Fe-24Cr-2Mo by austenitization due to nitrogen absorption. Tensile properties of the alloy after nitrogen absorption were improved by grain refinement process before nitrogen absorption. The tensile strength and 0.2% proof stress of the alloy with nitrogen absorption for 129.6 ks were much larger than those of 316L steel, while the elongation to fracture was much smaller than that of 316L steel. Therefore, small devices and parts with a maximum thickness or diameter of 4 mm were manufactured with this process in this study.

Light use efficiency (LUE ) is an important parameter for GPP and and NPP estimation model, cause by the existing model method to estimate the actual LUE is always simple and rough, which may lead to serious bias by GPP and NPP. The photochemical reflectance index ( PRI ) has great potential for direct estimation the actual LUE. In this paper, wheat in different nitrogen treatments was designed in field trial during Wheat growing period, for obtain photosynthesis and reflective hyperspectral data, and then LUE and PRI was calculated in critical period of wheat growth. The results show that, at different growth stages under three different nitrogen conditions, LUE and PRI value were significantly increased with increasing nitrogen absorption; Last longer, more capable of absorbing nitrogen amount, the correlation between LUE and PRI was better，for example, the correlation coefficient is obviously larger in heading stage than elongation stage for same nitrogen treatment.