Pin1 aggravates renal injury induced by ischemia and reperfusion in rats via Nrf2/HO-1 mediated endoplasmic reticulum stress

Purpose: To investigate the role of peptidyl-prolyl cis/trans isomerase 1 (Pin1) on renal ischemia-reperfusion (I/R) injury and underlying mechanism. Methods: By establishing the in vitro and in vivo models of renal I/R, the role of Pin1 was explored by using molecular assays. Results: In renal I/R, endogenous Pin1 level was up-regulated in I/R-impaired kidney. Suppression of Pin1 with juglone afforded protection against I/R-mediated kidney dysfunction, and reduced I/R-induced endoplasmic reticulum (ER) stress in vivo. Consistent with the in vivo results, repression of Pin1 with juglone or gene knockdown with si-Pin1 conferred cytoprotection and restricted hypoxia/reoxygenation (H/R)-driven ER stress in HK-2 cells. Simultaneously, further study uncovered that Nrf-2/HO-1 signals was the association between Pin1 and ER stress in response to renal I/R. In addition, Nrf-2/HO-1 signal pathway was inactivated after kidney exposed to I/R, as indicated by the down-regulation of Nrf-2/HO-1 levels. Furthermore, inhibition of Pin1 remarkably rescued the inactivation ofNrf-2/HO-1. Conclusions: Pin1 modulated I/R-mediated kidney injury in ER stress manner dependent on Nrf2-HO-1 pathway in I/R injury.

Quantitative evaluation of soil ion content using an imaginary part model of soil dielectric constant

An imaginary part model of soil dielectric constant for predicting the soil salinity status was developed based on a series of relations between dielectric imaginary part and soil bulk conductivity, soil bulk conductivity and soil solution electrical conductivity, and soil solution electrical conductivity and ion contents in soil using pot trials with different soil salinity levels in the 2008 growing season. This model was calibrated and tested with data from the 2009 growing season. The results showed that the inverted values of the total concentration of salt (Sc), Cl−, and Ca2+ at low frequencies (P-band of microwave observations) from the imaginary part model fitted well with the observed values, since root mean square errors (RMSEs) were 0.34 g kg−1, 0.09 g kg−1 and 0.13 g kg−1, respectively, but the inversion effect of Na+ was relatively poor. Moreover, the Sc, Cl−, and Na+ could be well inverted at high frequencies (C-band of microwave observations), since RMSEs were minor, with values of 0.25 g kg−1, 0.02 g kg−1, and 0.15 g kg−1, respectively. The close fit between the observed and inverted values indicated that the present models could be used to estimate soil ion content quickly and reliably under different saline conditions, which, when suitable measures are taken, can be used to reduce the effects of soil salinity on crop growth.

Quantitative evaluation of soil ion content using an imaginary part model of soil dielectric constant

An imaginary part model of soil dielectric constant for predicting the soil salinity status was developed based on a series of relations between dielectric imaginary part and soil bulk conductivity, soil bulk conductivity and soil solution electrical conductivity, and soil solution electrical conductivity and ion contents in soil using pot trials with different soil salinity levels in the 2008 growing season. This model was calibrated and tested with data from the 2009 growing season. The results showed that the inverted values of the total concentration of salt (Sc), Cl−, and Ca2+ at low frequencies (P-band of microwave observations) from the imaginary part model fitted well with the observed values, since root mean square errors (RMSEs) were 0.34 g kg−1, 0.09 g kg−1 and 0.13 g kg−1, respectively, but the inversion effect of Na+ was relatively poor. Moreover, the Sc, Cl−, and Na+ could be well inverted at high frequencies (C-band of microwave observations), since RMSEs were minor, with values of 0.25 g kg−1, 0.02 g kg−1, and 0.15 g kg−1, respectively. The close fit between the observed and inverted values indicated that the present models could be used to estimate soil ion content quickly and reliably under different saline conditions, which, when suitable measures are taken, can be used to reduce the effects of soil salinity on crop growth.(AU)

Spatial variability of soil hydraulic properties on a steep slope in the loess plateau of China

The understanding of the structure of the spatial variability of soil surface hydraulic properties on steep slopes is important for modeling infiltration and runoff processes. The objective of this study was to investigate the spatial variability of these properties on a steep slope of the Loess Plateau in northwest China. A 9600 m² area was systematically sampled in a grid of 106 points spaced 10 m x 10 m. Hydraulic properties were determined with a disc infiltrometer under multiple pressure heads (-15, -9, -6, -3, 0 cm) at each sample point. Classical and geo-statistical methods were used for data analysis. The results indicated that the variation of Gardner's a and hydraulic conductivities at all applied pressure heads was moderate and the heterogeneity for hydraulic conductivities increased as the applied pressure head increased. Along the slope, hydraulic conductivities generally decreased downwards, while the Gardner's a fluctuated slightly. The Gardner's a of the shaded aspect of the slope was greater than that of the sunny aspect. The hydraulic conductivities of the shaded aspect were greater at higher pressure heads as compared to the sunny aspect, but lower than those of the sunny aspect at lower pressure heads. Correlation analysis showed a negative correlation between hydraulic conductivity and soil organic matter and clay ( 0.01 mm) contents. Hydraulic conductivities at pressure heads of -3, -6, -9, -15 cm varied across the slope and their spatial dependence increased as the pressure head declined. The heterogeneity and spatial dependence of hydraulic properties were larger for the areas with shaded aspect as compared to the sunny aspect, however, as pressure decreased they showed a progressively increasing spatial structure, and their spatial structure behaved increasingly similar in both the shaded and sunny aspects.

A compreensão da estrutura da variabilidade especial das propriedades hidráulicas do solo de encostas íngremes é importante na modelagem dos processos de infiltração e de escoamento superficial da água. O objetivo deste estudo foi investigar a variabilidade destas propriedades em uma encosta íngreme do "Loess Plateau" do noroeste da China. Uma área de 9600 m² foi sistematicamente amostrada em um grid de 106 pontos espaçados de 10 m x 10 m. As propriedades hídricas foram determinadas com um infiltrômetro de disco operando sob múltiplas cargas hidráulicas (-15, -9, -6, -3, 0 cm) em cada ponto de observação. Métodos clássicos e geoestatísticos foram empregados na análise dos dados. Os resultados mostraram que a variação do índice a de Gardner e das condutividades hidráulicas em todas as cargas aplicadas foi moderada e que a heterogeneidade das condutividades hidráulicas aumentou à medida que a carga hidráulica aumentava. Na direção do declive, as condutividades geralmente decresceram a jusante, enquanto os a de Gardner flutuavam moderadamente. Os a de Gardner das encostas sombreadas foram maiores do que os das encostas ensolaradas. As condutividades hidráulicas das encostas sombreadas foram maiores para cargas hidráulicas maiores em comparação com as encostas ensolaradas, mas menores que as das encostas ensolaradas para cargas hidráulicas menores. A análise de correlação mostrou uma correlação negativa entre a condutividade hidráulica e os teores de matéria orgânica e argila ( 0.01 mm). As condutividades hidráulicas sob cargas de -3, -6, -9, -15 cm variaram em toda encosta e suas dependências espaciais aumentaram à medida que a carga diminuía. A heterogeneidade e a dependência espacial das propriedades hídricas foram maiores para as áreas em encostas sombreadas em comparação com as encostas ensolaradas, entretanto, à medida que a carga hidráulica decrescia, elas apresentaram progressivamente uma estrutura especial mais intensa, e esta estrutura se comportou cada vez mais similar para as encostas sombreadas e ensolaradas.

Soil water content temporal-spatial variability of the surface layer of a Loess Plateau hillside in China

Surface soil moisture exhibits an important variability in terms of spatial and temporal domains, which may result in critical uncertainties for agricultural water management. The purposes of this study were (i) to characterize the temporal dynamics and stability of the spatial variability of the surface 0-6 cm soil water content on a hill-slope; (ii) to investigate issues related to soil moisture conditions including dominating factors on soil moisture and to the estimation of the mean . During a period of more than one month was measured on thirteen days by Frequency Domain Reflectometry using a 10 x 10 m grid of measurement points covering a 60 x 280 m domain within a hill-slope of the Loess Plateau in China. Soil water content exhibited a moderate variability for each measurement date, and the correlation length (l) for ranged from 8.4 to 27.7 m. With the soil becoming drier, l decreased, the CV% and the sampling number for accurate mean estimation increased. Aspect, elevation, organic matter content, clay content, and bulk density were the main influencing factors, whose extent of influence weakened with decreasing . Based on time stability analysis and on the correlation of mean relative difference of with the relative difference of dominating factors, mean q values were well estimated, with a better accuracy under wetter conditions.

A umidade da camada superficial do solo apresenta uma variabilidade importante nos domínios espacial e temporal, que pode levar a incertezas críticas para o manejo agrícola da água. Os objetivos deste estudo incluíram: (i) a caracterização da dinâmica temporal e da estabilidade da variabilidade espacial da umidade da camada 0-6 cm em uma encosta em declive; (ii) investigação de parâmetros ligados às condições de umidade, incluindo fatores dominantes da umidade na estimativa de um valor médio de q. Durante um período de mais de um mês, q foi medida em 13 dias com auxílio da técnica da Refletometria do Domínio da Frequência, em uma grade de 10 x 10 cm, cobrindo uma área de 60 x 280 m, situada em uma encosta do "Loess Plateau" da China. A umidade do solo apresentou variabilidade moderada em cada data de medida e o alcance da correlação (l) para q variou de 8,4 a 27,7 m. Com o solo mais seco, l decresceu, o CV% e o número de amostras necessário para obter uma média precisa, aumentaram. O aspecto, a elevação, o conteúdo de matéria orgânica e a densidade do solo foram os principais fatores interferentes na umidade, cuja intensidade de influência diminuiu com a umidade. Baseado na análise de estabilidade temporal e na correlação da diferença relativa média de com a diferença relativa média dos fatores dominantes, valores médios de q puderam ser mais bem estimados, com maior precisão sobre condições mais úmidas.

Soil water content temporal-spatial variability of the surface layer of a Loess Plateau hillside in China

Surface soil moisture exhibits an important variability in terms of spatial and temporal domains, which may result in critical uncertainties for agricultural water management. The purposes of this study were (i) to characterize the temporal dynamics and stability of the spatial variability of the surface 0-6 cm soil water content on a hill-slope; (ii) to investigate issues related to soil moisture conditions including dominating factors on soil moisture and to the estimation of the mean . During a period of more than one month was measured on thirteen days by Frequency Domain Reflectometry using a 10 x 10 m grid of measurement points covering a 60 x 280 m domain within a hill-slope of the Loess Plateau in China. Soil water content exhibited a moderate variability for each measurement date, and the correlation length (l) for ranged from 8.4 to 27.7 m. With the soil becoming drier, l decreased, the CV% and the sampling number for accurate mean estimation increased. Aspect, elevation, organic matter content, clay content, and bulk density were the main influencing factors, whose extent of influence weakened with decreasing . Based on time stability analysis and on the correlation of mean relative difference of with the relative difference of dominating factors, mean q values were well estimated, with a better accuracy under wetter conditions.

A umidade da camada superficial do solo apresenta uma variabilidade importante nos domínios espacial e temporal, que pode levar a incertezas críticas para o manejo agrícola da água. Os objetivos deste estudo incluíram: (i) a caracterização da dinâmica temporal e da estabilidade da variabilidade espacial da umidade da camada 0-6 cm em uma encosta em declive; (ii) investigação de parâmetros ligados às condições de umidade, incluindo fatores dominantes da umidade na estimativa de um valor médio de q. Durante um período de mais de um mês, q foi medida em 13 dias com auxílio da técnica da Refletometria do Domínio da Frequência, em uma grade de 10 x 10 cm, cobrindo uma área de 60 x 280 m, situada em uma encosta do "Loess Plateau" da China. A umidade do solo apresentou variabilidade moderada em cada data de medida e o alcance da correlação (l) para q variou de 8,4 a 27,7 m. Com o solo mais seco, l decresceu, o CV% e o número de amostras necessário para obter uma média precisa, aumentaram. O aspecto, a elevação, o conteúdo de matéria orgânica e a densidade do solo foram os principais fatores interferentes na umidade, cuja intensidade de influência diminuiu com a umidade. Baseado na análise de estabilidade temporal e na correlação da diferença relativa média de com a diferença relativa média dos fatores dominantes, valores médios de q puderam ser mais bem estimados, com maior precisão sobre condições mais úmidas.

Spatial variability of soil hydraulic properties on a steep slope in the loess plateau of China

The understanding of the structure of the spatial variability of soil surface hydraulic properties on steep slopes is important for modeling infiltration and runoff processes. The objective of this study was to investigate the spatial variability of these properties on a steep slope of the Loess Plateau in northwest China. A 9600 m² area was systematically sampled in a grid of 106 points spaced 10 m x 10 m. Hydraulic properties were determined with a disc infiltrometer under multiple pressure heads (-15, -9, -6, -3, 0 cm) at each sample point. Classical and geo-statistical methods were used for data analysis. The results indicated that the variation of Gardner's a and hydraulic conductivities at all applied pressure heads was moderate and the heterogeneity for hydraulic conductivities increased as the applied pressure head increased. Along the slope, hydraulic conductivities generally decreased downwards, while the Gardner's a fluctuated slightly. The Gardner's a of the shaded aspect of the slope was greater than that of the sunny aspect. The hydraulic conductivities of the shaded aspect were greater at higher pressure heads as compared to the sunny aspect, but lower than those of the sunny aspect at lower pressure heads. Correlation analysis showed a negative correlation between hydraulic conductivity and soil organic matter and clay ( 0.01 mm) contents. Hydraulic conductivities at pressure heads of -3, -6, -9, -15 cm varied across the slope and their spatial dependence increased as the pressure head declined. The heterogeneity and spatial dependence of hydraulic properties were larger for the areas with shaded aspect as compared to the sunny aspect, however, as pressure decreased they showed a progressively increasing spatial structure, and their spatial structure behaved increasingly similar in both the shaded and sunny aspects.

A compreensão da estrutura da variabilidade especial das propriedades hidráulicas do solo de encostas íngremes é importante na modelagem dos processos de infiltração e de escoamento superficial da água. O objetivo deste estudo foi investigar a variabilidade destas propriedades em uma encosta íngreme do "Loess Plateau" do noroeste da China. Uma área de 9600 m² foi sistematicamente amostrada em um grid de 106 pontos espaçados de 10 m x 10 m. As propriedades hídricas foram determinadas com um infiltrômetro de disco operando sob múltiplas cargas hidráulicas (-15, -9, -6, -3, 0 cm) em cada ponto de observação. Métodos clássicos e geoestatísticos foram empregados na análise dos dados. Os resultados mostraram que a variação do índice a de Gardner e das condutividades hidráulicas em todas as cargas aplicadas foi moderada e que a heterogeneidade das condutividades hidráulicas aumentou à medida que a carga hidráulica aumentava. Na direção do declive, as condutividades geralmente decresceram a jusante, enquanto os a de Gardner flutuavam moderadamente. Os a de Gardner das encostas sombreadas foram maiores do que os das encostas ensolaradas. As condutividades hidráulicas das encostas sombreadas foram maiores para cargas hidráulicas maiores em comparação com as encostas ensolaradas, mas menores que as das encostas ensolaradas para cargas hidráulicas menores. A análise de correlação mostrou uma correlação negativa entre a condutividade hidráulica e os teores de matéria orgânica e argila ( 0.01 mm). As condutividades hidráulicas sob cargas de -3, -6, -9, -15 cm variaram em toda encosta e suas dependências espaciais aumentaram à medida que a carga diminuía. A heterogeneidade e a dependência espacial das propriedades hídricas foram maiores para as áreas em encostas sombreadas em comparação com as encostas ensolaradas, entretanto, à medida que a carga hidráulica decrescia, elas apresentaram progressivamente uma estrutura especial mais intensa, e esta estrutura se comportou cada vez mais similar para as encostas sombreadas e ensolaradas.