Time-Lag Effect of Dietary Fiber and Fat Intake Ratio on Japanese Colon Cancer Mortality

The daily intake of total dietary fiber (TDF) was evaluated from data of the National Nutrition Survey (NNS) in Japan for 41 years since 1947. An interrelationship between the nutrient intake, including TDF, and the mortality from colon cancer in Japanese people was calculated by a simple correlation coefficient and time-series correlation coeffcient.TDF intake per capita decreased rapidly from 27.4 g in 1947 to 15.8 g in 1963, and subsequently decreased by a lesser rate to 15.3 g in 1987. Fat intake increased rapidly from 18.0 g in 1950 to 56.6 g in 1987.The age-adjusted mortality from colon cancer shows a significant positive correlation with both the intakes of animal protein and of total fat, and the fat energy ratio. A time-series analysis indicates that the mortality from colon cancer was negatively correlated with TDF with a 15-27 year delay, the maximum correlation existing with a 23-year lag (r = -0.947). The TDF intake was less than 17.9 g in 1965. At the same time, the mortality from colon cancer increased rapidly. A fat/TDF ratio above 3.0 resulted in a rapid increase in colon cancer mortality.The non-adjusted mortality from colon cancer has much the same interrelationship with TDF and fat intake as the adjusted figures. It is suggested that the cause of the increased mortality from colon cancer in Japan is positively related to the increased intake of fat and protein. In addition, the decrease in TDF intake has accelerated the mortality of colon cancer after a delay of 23-24 years. The importance of fat/TDF as a nutritional criterion for the incidence of colon cancer needs to be better recognized

Time-lagged and cumulative effects of drought and anthropogenic activities on China's vegetation greening from 1990 to 2018

Previous studies have confirmed the time-lagged and cumulative effects of drought and anthropogenic activities on vegetation growth,but these studies focus on the time-lagged effect of drought and are poorly known how vegetation productivity responds to anthropogenic activities.Here,based on the reconstructed Normalized Difference Vegetation Index,the Standardized Precipitation Evapotranspiration Index and land use degree comprehensive index,we diagnosed the spatiotemporal pattern of vegetation and drought,investigated time-lagged and cumulative effects of drought and anthropogenic activities over China through the month where the maximum correlation coefficient occurred.It revealed that the browning trend of 32.21%of vegetated lands was covered by overall greening,especially northwestern China.Drought intensified with a rate of 0.0014/year.in 66.41%and 54.57%of the vegetated lands had time-lagged and cumulative response to drought,with a shorter timescales of 1–4 months,indicating the higher sensitivity of vegetation growth to drought.There was a U-shaped relationship between moisture conditions and vegetation response time.49.9%of China’s vegetation showed time-lagged effects to anthropogenic activities,with a longer timescales of 6–10 years,demonstrating that anthropogenic activities triggered ecological changes but vegetation ecosystems cannot keep pace.The accumulated and time-lagged years declined with increased land use intensity.

Considering time-lag effects can improve the accuracy of NPP simulation using a light use efficiency model

Most terrestrial models synchronously calculate net primary productivity(NPP)using the input climate variable,without the consideration of time-lag effects,which may increase the uncertainty of NPP simulation.Based on Normalized Difference Vegetation Index(NDVI)and climate data,we used the time lag cross-correlation method to investigate the time-lag effects of temperature,precipitation,and solar radiation in different seasons on NDVI values.Then,we selected the Carnegie-Ames-Stanford approach(CASA)model to estimate the NPP of China from 2002 to 2017.The results showed that the response of vegetation growth to climate factors had an obvious lag effect,with the longest time lag in solar radiation and the shortest time lag in temperature.The time lag of vegetation to the climate variable showed great tempo-spatial heterogeneities among vegetation types,climate types,and vegetation growth periods.Based on the validation using eddy covariance data,the results showed that the simulation accuracy of the CASA model considering the time-lag effects was effectively improved.By considering the time-lag effects,the average total amount of NPP modeled by CASA during 2001-2017 in China was 3.977 PgC a^(−1),which is 11.37%higher than that of the original model.This study highlights the importance of considering the time lag for the simulation of vegetation growth,and provides a useful tool for the improvement of the vegetation productivity model.

The Relationship between Normalized Difference Vegetation Index(NDVI) and Climate Factors in the Semiarid Region:A Case Study in Yalu Tsangpo River Basin of Qinghai-Tibet Plateau

The Yalu Tsangpo River basin is a typical semi-arid and cold region in the Qinghai-Tibet Plateau, where significant climate change has been detected in the past decades. The objective of this paper is to demonstrate how the regional vegetation, especially the typical plant types, responds to the climate changes. In this study, the model of gravity center has been firstly introduced to analyze the spatial-temporal relationship between NDVI and climate factors considering the time-lag effect. The results show that the vegetation grown has been positively influenced by the rainfall and precipitation both in moving tracks of gravity center and time-lag effect especially for the growing season during the past thirteen years. The herbs and shrubs are inclined to be influenced by the change of rainfall and temperature, which is indicated by larger positive correlation coefficients at the 0.05 confidence level and shorter lagging time. For the soil moisture, the significantly negative relationship of NDV-PDI indicates that the growth and productivity of the vegetation are closely related to the short-term soil water, with the correlation coefficients reaching the maximum value of o.81 at Lag 0-1. Among the typicalvegetation types of plateau, the shrubs of low mountain, steppe and meadow are more sensitive to the change of soil moisture with coefficients of -0.95, -0.93, -0.92, respectively. These findings reveal that the spatial and temporal heterogeneity between NDVI and climatic factors are of great ecological significance and practical value for the protection of eco-environment in Qinghai-Tibet Plateau.

Livestock Dynamic Responses to Climate Change in Alpine Grasslands on the Northern Tibetan Plateau:Forage Consumption and Time-lag Effects

Climate change and forage-intake are important components of livestock population systems,but our knowledge about the effects of changes in these properties on livestock is limited,particularly on the Northern Tibetan Plateau.Based on corresponding independent models（CASA and TEM）,a human-induced NPP（NPPH） value and forage-intake threshold were obtained to determine their influences on livestock population fluctuation and regrowth on the plateau.The intake threshold value provided compatible results with livestock population performance.If the forage-intake was greater than the critical value of 1.9（kg DM d^（-1） sheep^（-1））,the livestock population increased;otherwise,the livestock population decreased.It takes four years to transfer a disturbance in primary productivity to the next trophic level.The relationships between livestock population and NPP_H value determined population dynamics via the forage-intake value threshold.Improved knowledge on lag effects will advance our understanding of drivers of climatic changes on livestock population dynamics.

Impact of ERP Investment on Company Performance: Evidence from Manufacturing Firms in China

Information Technology （IT） investments, especially Enterprise Resource Planning （ERP） systems, are critical for the survival and development of companies. Therefore, understanding the impact of ERP in- vestment is of great importance to managers and researchers. As a corporate performance indicator, Tobin＇s Q has some inherent advantages compared to other accounting indicators, and it can better reflect the con- tribution of ERP investment to company performance. This study employs multiple regression models to examine the impact of ERP investment on Tobin＇s Q. The sample consists of 126 manufacturing companies listed on the Shanghai and Shenzhen Stock Exchanges from 1999 to 2007. Empirical results show that in the first three years after ERP implementation, there is no significant change in Tobin＇s Q; however, in the fourth year, Tobin＇s Q increases significantly. The results indicate that, as a strategic long-term investment accompanied by large-scale business process reengineering and organizational learning, ERP implementa- tion has time-lagged effects; nonetheless, it eventually produces significant benefits.