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Single-phase Gd[sub 2]Co[sub 17-x]V[sub x] compounds (x = 0.0-1.5) crystallizing in the rhombohedral Th[sub 2]Zn[sub 17] structure have been synthesized. The lattice parameters a and c of the compounds increase linearly with increasing V content, and the rate of increase of c is about 2.5 times as large as that of a. Substitution of a small amount of V atoms (x = 0.3) for Co atoms leads to the occurrence of uniaxial magnetocrystalline anisotropy of Gd[sub 2]Co[sub 17-x]V[sub x]. The anisotropy field H[sub A] increases drastically with increasing V content. The variations of both the lattice parameters and the magnetocrystalline anisotropy with V content suggest a preferential occupation of the V atoms at the 6c dumbbell site. The Curie temperature T[sub C], saturation moment M[sub S], and average Co moment 〈μ[sub Co]〉 of the compounds decrease greatly as the V content increases. The rapid decrease of T[sub C] is essentially attributed to a serious weakening of the Co-Co interactions due to the preferential occupation of the V atoms at the 6c site. The effect of a strong hybridization between the V and Co atoms is plausibly responsible for the decreases of the Ms and 〈μ[sub Co]〉. [ABSTRACT FROM AUTHOR]

Bacteria play essential roles in soil ecosystems. This study aims to investigate rice rhizosphere bacterial communities, soil nutrition, and grain yield affected by long-term (30 years) fertilization practices. Four fertilizations were applied to experimental red paddy soils: no fertilizer (NF), chemical fertilizer (CF), harvested residue returned to soil (HRR), and 60% organic manure plus chemical fertilizer (OCF). Bacterial communities were then assessed by means of denaturing gradient gel electrophoresis (DGGE) targeting 16S rRNA genes. Results showed that the bacterial community structure of OCF was similar to HRR, which was the most diverse and stable compared to the other treatments. Moreover, CF’s effects were similar to NF, which was markedly less diverse. Eight bacterial phyla were identified by sequence analysis of the DGGE bands from rhizosphere inhabitants in the red paddy soils. In addition, soil microbial biomass C and N were significantly higher in HRR and OCF than in CF and NF. Furthermore, double rice grain yield and dry matter in OCF plots were significantly highest (P < 0.05). Long-term treatment of organic matter containing fertilizers promoted rhizospheric bacterial diversity and soil quality. The combination of inorganic and organic fertilizers (OCF) improved grain yields more than solely inorganic (CF) or organic (HRR) fertilizers. [ABSTRACT FROM AUTHOR]

The crystal structure and superconducting properties of RuSr[sub 2-x]Ba[sub x]GdCu[sub 2]O[sub 8] (0<=x<=0.1) have been investigated. X-ray powder diffraction (XRD) patterns show that the solid solution range is 0<=x<=0.1. The superconducting transition temperature was raised up to 35 K (zero) and 62 K (onset) for x=0.07, from 16 K (zero) and 45 K (onset) for x=0.0, and then T[sub C] decreases with x when x>0.07. Rietveld refinement for XRD data of RuSr[sub 2-x]Ba[sub x]GdCu[sub 2]O[sub 8] show that the apical Cu–O(1) bond length increases with an increase of x, while the Ru–O(1) bond length decreases, This may account for the enhancement of the superconducting transition temperature. © 2004 American Institute of Physics. [ABSTRACT FROM AUTHOR]

Crystal structure and magnetic properties of the NdCo[sub 9.5-x]Fe[sub x]V[sub 2.5] compounds with x=0–3.5 have been investigated. The lattice parameters increase linearly with the Fe content and the Curie temperature increases substantially at small amount of Fe content and then gradually with the further increase of x. A domain-wall pinning phenomenon was observed in all of the compounds and becomes less obvious as x increases. At a higher field, the compounds exhibit a field-induced metamagnetic transition. The critical field for the metamagnetic transition increases first then decreases with the Fe content, whereas the difference of the magnetization between 14 and 5 T increases with x. The observation can be understood by considering an interplay of the volume expansion, enhanced exchange coupling parameter J[sub RT] and the T sublattice moment μ[sub T] due to the Fe substitution for Co. © 2004 American Institute of Physics. [ABSTRACT FROM AUTHOR]

Rice (Oryza sativa L.) is one of the most important cereal crops in the world and a potentially important source of zinc (Zn) in the diet. The improvement of Zn content of rice is a global challenge with implications for both rice production and human health. The objective of the present study was to identify the effects of nitrogen (N) fertilizer rates and Zn application methods on Zn content of rice by evaluating rice production on native soils with different Zn availabilities in 2010/11. The results indicated that Zn application increased rice grain yield and Zn content in grains compared with the control; however, this effect was also affected by the native soil Zn availability, N fertilizer rate and Zn fertilizer application method. The native soil Zn status was the dominant factor influencing grain yield and grain Zn content in response to Zn fertilizer application. Grain Zn content ranged from 19·74 to 26·93 mg/kg under the different Zn statuses. The results also indicated that Zn application method has a significant influence on grain yield. Application of Zn fertilizer to the soil was more effective than the foliar spray on rice grain yield; however, the foliar spray resulted in a greater increase in grain Zn content when compared with soil application. Grain Zn content was affected by application method and displayed the following general trend: soil application + foliar spray > foliar spray > soil application. The experiments investigating the effect of N fertilizer rate combined with Zn application method showed a clear increase in both grain yield and Zn content as the N fertilizer level increased from 200 to 300 kg/ha. In addition, the results also indicated that N content and accumulation increased in all plant tissues, which suggests that Zn application might influence the uptake and translocation of N in rice plants. These results suggest that soil application in addition to a foliar spray of Zn should be considered as an important strategy to increase grain yield and grain Zn content of rice grown in soils with low background levels of Zn-associated diethylene triamine pentaacetate acid. Moreover, this process could be further strengthened by a high N application rate. In conclusion, these results demonstrate the potential of optimizing nutrient management using Zn fertilizer to obtain higher grain yields and higher grain Zn content in fields with low native Zn status. [ABSTRACT FROM PUBLISHER]

Background Adipose afferent reflex ( AAR) contributes to sympathetic activation and hypertension. Paraventricular nucleus ( PVN) plays an important role in AAR and sympathetic outflow. The aim of the present study was to determine whether PVN mediates AAR response to insulin in a rat model of insulin resistance ( IR). Methods Male Sprague-Dawley rats were randomly divided into Control and IR groups. Insulin resistance was induced by supplementing fructose (125 g L−1, 12 weeks) in the drinking water. Renal sympathetic nerve activity ( RSNA) and mean arterial pressure ( MAP) were recorded in anesthetized rats. AAR was evaluated by the RSNA and MAP responses to injection of capsaicin into four sites of right inguinal white adipose tissue. Results Rats in IR group showed a rise in plasma noradrenaline ( NE), glucose, insulin and triglyceride levels, left ventricular weight, systolic blood pressure, homeostasis model assessment of insulin resistance ( HOMA- IR) and PVN glucose and insulin levels, melanocortin 4 type receptors ( MC4Rs) protein expression, but not MC3Rs and insulin receptors. Compared with Control group, AAR in IR group was significantly enhanced, which contributed to the elevation of NE level; and insulin microinjection into the PVN or the third ventricle significantly strengthened AAR, which was attenuated by pre-treatment with MC4Rs antagonist HS024 and anti-insulin affibody, respectively, but not insulin receptors antagonist S961. Conclusion The enhanced AAR participates in sympathetic activation in IR, which can be strengthened by PVN insulin. PVN MC4Rs mediate the AAR response to insulin in IR, but not MC3Rs and insulin receptors. [ABSTRACT FROM AUTHOR]

Aim Cardiac sympathetic afferent reflex ( CSAR) participates in sympathetic over-excitation. Superoxide anions and angiotensin II (Ang II) mechanisms are associated with sympathetic outflow and CSAR in the paraventricular nucleus ( PVN). This study was designed to investigate whether PVN superoxide anions mediate CSAR and Ang II-induced CSAR enhancement response in fructose-induced insulin resistance ( IR) rats. Methods CSAR was evaluated with the changes of renal sympathetic nerve activity ( RSNA) and mean arterial pressure ( MAP) responses to the epicardial application of capsaicin ( CAP) in anaesthetized rats. Results Compared with Control rats, IR rats showed that CSAR, PVN NAD(P)H oxidase activity, superoxide anions, malondialdehyde ( MDA), Ang II and AT1 receptor levels were significantly increased, whereas PVN superoxide dismutase ( SOD) and catalase ( CAT) activities were decreased. In Control and IR rats, PVN microinjection of superoxide anions scavengers tempol, tiron and PEG- SOD (an analogue of endogenous superoxide dismutase) or inhibition of PVN NAD(P)H oxidase with apocynin caused significant reduction of CSAR, respectively, but DETC (a superoxide dismutase inhibitor) strengthened the CSAR. PVN pre-treatment with tempol abolished, whereas DETC potentiated, Ang II-induced CSAR enhancement response. Moreover, PVN pre-treatment with tempol or losartan prevented superoxide anions increase caused by Ang II in IR rats. Conclusion PVN superoxide anions mediate CSAR and Ang II-induced CSAR response in IR rats. In IR state, increased NAD(P)H oxidase activity and decreased SOD and CAT activities in the PVN promote superoxide anions increase to involve in CSAR enhancement. Ang II may increase NAD(P)H oxidase activity via AT1 receptor to induce superoxide anion production. [ABSTRACT FROM AUTHOR]

The general relationships between vegetation and water yield under different climatic regimes are well established at a small watershed scale in the past century. However, applications of these basic theories to evaluate the regional effects of land cover change on water resources remain challenging due to the complex interactions of vegetation and climatic variability and hydrologic processes at the large scale. The objective of this study was to explore ways to examine the spatial and temporal effects of a large ecological restoration project on water yield across the Loess Plateau region in northern China. We estimated annual water yield as the difference between precipitation input and modelled actual evapotranspiration (ET) output. We constructed a monthly ET model using published ET data derived from eddy flux measurements and watershed streamflow data. We validated the ET models at a watershed and regional levels. The model was then applied to examine regional water yield under land cover change and climatic variability during the implementation of the Grain-for-Green (GFG) project during 1999-2007. We found that water yield in 38% of the Loess Plateau area might have decreased (1-48mm per year) as a result of land cover change alone. However, combined with climatic variability, 37% of the study area might have seen a decrease in water yield with a range of 1-54mm per year, and 35% of the study area might have seen an increase with a range of 1-10mm per year. Across the study region, climate variability masked or strengthened the water yield response to vegetation restoration. The absolute annual water yield change due to vegetation restoration varied with precipitation regimes with the highest in wet years, but the relative water yield changes were most pronounced in dry years. We concluded that the effects of land cover change associated with ecological restoration varied greatly over time and space and were strongly influenced by climatic variability in the arid region. The current regional vegetation restoration projects have variable effects on local water resources across the region. Land management planning must consider the influences of spatial climate variability and long-term climate change on water yield to be more effective for achieving environmental sustainability. [ABSTRACT FROM AUTHOR]

The general relationships between vegetation and water yield under different climatic regimes are well established at a small watershed scale in the past century. However, applying the basic theories to evaluate the regional effects of land cover change on water resources has been rarely done due to the complex interactions of vegetation and climatic variability and hydrologic processes at the large scale. The objective of this study was to explore ways to examine the spatial and temporal effects of a large ecological restoration project on water yield across the Loess Plateau region in Northern China. We estimated annual water yield as the difference between precipitation input and modeled actual evapotranspiration (ET) output. We constructed a monthly ET model using published eddy flux ET measurements, ET estimates derived from local watershed streamflow data. We validated the ET models at a watershed and regional levels. The model was then applied to examine regional water yield under land cover change and climatic variability during the implementation of the Grain-for-Green (GFG) project during 1999-2007. We found that water yield in 38% of the Loess Plateau area as a whole might have decreased (1-48mmyr-1) as a result of land cover change alone. However, combined with climatic variability, 37% of the study area might have seen a decrease in water yield with a range of 1-54mmyr-1, and 35% of the study area might have seen an increase with a range of 1-10mmyr-1. Across the study region, climate variability masked or strengthened the water yield response to vegetation restoration. The absolute annual water yield change due to vegetation restoration varied with precipitation regimes with the highest in wet years, but the relative water yield changes were most pronounced in dry years. When compared to findings at the plot or catchment-scale, this study suggested that regional hydrologic effects of vegetation restoration practices had a rather complex pattern due to both spatial differences in climatic regimes and vegetation response. We concluded that the effects of land cover change associated with ecological restoration varied greatly over time and space and were strongly influenced by climatic variability in the arid region. The current regional vegetation restoration projects have variable effects on local water resources across the region. Land management planning must consider the influences of spatial climate variability and long-term climate change on water yield to be more effective and achieve environmental sustainability. [ABSTRACT FROM AUTHOR]

Aims: To develop a fast, accurate, objective and nondestructive method for monitoring barley tempeh fermentation. Methods and Results: Barley tempeh is a food made from pearled barley grains fermented with Rhizopus oligosporus. Rhizopus oligosporus growth is important for tempeh quality, but quantifying its growth is difficult and laborious. A system was developed for analysing digital images of fermentation stages using two image processing methods. The first employed statistical measures sensitive to image colour and surface structure, and these statistical measures were highly correlated ( r = 0·92, n = 75, P < 0·001) with ergosterol content of tempeh fermented with R. oligosporus and lactic acid bacteria (LAB). In the second method, an image-processing algorithm optimized to changes in images of final tempeh products was developed to measure number of visible barley grains. A threshold of 5 visible grains per Petri dish indicated complete tempeh fermentation. When images of tempeh cakes fermented with different inoculation levels of R. oligosporus were analysed the results from the two image processing methods were in good agreement. Conclusion: Image processing proved suitable for monitoring barley tempeh fermentation. The method avoids sampling, is nonintrusive, and only requires a digital camera with good resolution and image analysis software. Significance and Impact of the Study: The system provides a rapid visualization of tempeh product maturation and qualities during fermentation. Automated online monitoring of tempeh fermentation by coupling automated image acquisition with image processing software could be further developed for process control. [ABSTRACT FROM AUTHOR]

Single-phase compounds NdCo[SUB12-x]V[SUBx] (x=2.2-2.6) crystallizing in the tetragonal ThMn[SUB12] structure with space group I4/mmm are synthesized. The lattice parameters a and c increase linearly with increasing V content. The Curie temperature of the compounds shows a linear decrease from 309 K for x=2.2 to 147 K for x=2.6. A domain-wall pinning phenomenon is observed in all of the compounds. It is intriguing that the Nd ions seem to make no contribution to the total moment of the compounds in an applied magnetic field up to 50 kOe. A further increase of the applied field induces a moment of a Nd sublattice that ferromagnetically couples with the moment of a Co sublattice. The instability of the Nd moment in NdCo[SUB12-x]V[SUBx] compounds can be well understood by the local environment effect. [ABSTRACT FROM AUTHOR]