Impulsivity, life stress, refusal efficacy, and problem gambling among Chinese: Testing the diathesis-stress-coping model.

This study extended the diathesis-stress-coping model (Lazarus & Folkman, 1984) to understand problem gambling in Chinese societies. We examined core model components of impulsivity trait (diathesis), life stress, and gambling refusal efficacy (coping efficacy) with 942 Chinese college students and 153 Chinese gamblers. Results showed that the three core model components exerted main effects on problem gambling for both samples. Among college students, refusal efficacy interacted with impulsivity to influence problem gambling in male and female students, and interacted with life stress in male students only. In particular, more severe problem gambling was associated with higher impulsivity in low- but not high-efficacy students, and with higher stress in low- but not high-efficacy male students. Among gamblers, impulsivity interacted with life stress to influence problem gambling. In the high stress condition, high- relative to low-impulsivity gamblers reported more severe problem gambling, but this pattern was not found in the low-stress condition. (PsycINFO Database Record (c) 2011 APA, all rights reserved)     

Understanding safe performance in rapidly evolving systems: a risk management analysis of the 2010 US financial market Flash Crash with Rasmussen's risk management framework

Systemic events or widespread disruptions in financial markets like the Flash Crash are a public concern as they jeopardise investors’ confidence in financial markets and result in financial losses for market participants. Federal regulations for financial markets do not keep pace with the evolution and growth of financial technology including advances in algorithmic and high-frequency trading (HFT). We report an analysis of the Flash Crash which occurred on 6 May 2010 using Rasmussen's 1997 risk management framework. While the framework has been validated on a number of well-documented accidents, our work examines the framework in the context of a large-scale adverse event associated with complex technologies and automated systems capable of evolving over time. Our contribution is a set of implications of the Flash Crash associated with Rasmussen's propositions. These implications would inform regulators and risk assessment methods for rapidly evolving complex socio-technical systems.     

Influence of packing density and stress on the dynamic response of granular materials

Laboratory geophysics tests including bender elements and acoustic emission measure the speed of propagation of stress or sound waves in granular materials to derive elastic stiffness parameters. This contribution builds on earlier studies to assess whether the received signal characteristics can provide additional information about either the material’s behaviour or the nature of the material itself. Specifically it considers the maximum frequency that the material can transmit; it also assesses whether there is a simple link between the spectrum of the received signal and the natural frequencies of the sample. Discrete element method (DEM) simulations of planar compression wave propagation were performed to generate the data for the study. Restricting consideration to uniform (monodisperse) spheres, the material fabric was varied by considering face-centred cubic lattice packings as well as random configurations with different packing densities. Supplemental analyses, in addition to the DEM simulations, were used to develop a more comprehensive understanding of the system dynamics. The assembly stiffness and mass matrices were extracted from the DEM model and these data were used in an eigenmode analysis that provided significant insight into the observed overall dynamic response. The close agreement of the wave velocities estimated using eigenmode analysis with the DEM results confirms that DEM wave propagation simulations can reliably be used to extract material stiffness data. The data show that increasing either stress or density allows higher frequencies to propagate through the media, but the low-pass wavelength is a function of packing density rather than stress level. Prior research which had hypothesised that there is a simple link between the spectrum of the received signal and the natural sample frequencies was not substantiated.     

Legume,cropping intensity,and N-fertilization effects on soil attributes and processes from an eight-year-old semiarid wheat system

In the North American northern Great Plains (NGP), legumes are promising summer fallow replacement/cropping intensification options that may decrease dependence on nitrogen (N) fertilizer in small grain systems and mitigate effects of soil organic matter (SOM) losses from summer fallow. Benefits may not be realized immediately in semiarid conditions though, and longer-term effects of legumes and intensified cropping in this region are unclear, particularly in no-till systems. We compared effects of four no-till wheat (Triticum aestivum L.) cropping systems–summer fallow–wheat (F–W), continuous wheat (CW), legume green manure (pea, Pisum sativum L.)—wheat (LGM–W), and pea–wheat (P–W)—on select soil attributes in an 8-year-old rotation study, and N fertilizer effects on C and N mineralization on a duplicate soil set in a laboratory experiment. We analyzed potentially mineralizable carbon and nitrogen (PMC and PMN) and mineralization trends with a nonlinear model, microbial biomass carbon (MB-C), and wet aggregate stability (WAS). Legume-containing systems generally resulted in higher PMC, PMN, and MB-C, while intensified systems (CW and P–W) had higher WAS. Half-lives of PMC were shortest in intensified systems, and were longest in legume systems (LGM–W and P–W) for PMN. Nitrogen addition depressed C and N mineralization, particularly in CW, and generally shortened the half-life of mineralizable C. Legumes may increase long-term, no-till NGP agroecosystem resilience and sustainability by (1) increasing the available N-supply (~26–50 %) compared to wheat-only systems, thereby reducing the need for N fertilizer for subsequent crops, and (2) by potentially mitigating negative effects of SOM loss from summer fallow.     

Quantification of Drug Transport Function across the Multiple Resistance-Associated Protein 2 (Mrp2) in Rat Livers

To understand the transport function of drugs across the canalicular membrane of hepatocytes, it would be important to measure concentrations in hepatocytes and bile. However, these concentration gradients are rarely provided. The aim of the study is then to measure these concentrations and define parameters to quantify the canalicular transport of drugs through the multiple resistance associated-protein 2 (Mrp2) in entire rat livers. Besides drug bile excretion rates, we measured additional parameters to better define transport function across Mrp2: (1) Concentration gradients between hepatocyte and bile concentrations over time; and (2) a unique parameter (canalicular concentration ratio) that represents the slope of the non-linear regression curve between hepatocyte and bile concentrations. This information was obtained in isolated rat livers perfused with gadobenate dimeglumine (BOPTA) and mebrofenin (MEB), two hepatobiliary drugs used in clinical liver imaging. Interestingly, despite different transport characteristics including excretion rates into bile and hepatocyte clearance into bile, BOPTA and MEB have a similar canalicular concentration ratio. In contrast, the ratio was null when BOPTA was not excreted in bile in hepatocytes lacking Mrp2. The canalicular concentration ratio is more informative than bile excretion rates because it is independent of time, bile flows, and concentrations perfused in portal veins. It would be interesting to apply such information in human liver imaging where hepatobiliary compounds are increasingly investigated.     

Nutritive value of the larvae of raphia palm beetle (Oryctes rhinoceros) and weevil (Rhyncophorus pheonicis)

The proximate nutrient composition, energy value, mineral concentrations, amino acid composition and chemical score of the larvae of raphia palm beetle (Oryctes rhinoceros) and weevil (Rhyncophorus pheonicis) were evaluated. Values of moisture, ash and crude protein were significantly (p < 0.05) higher in O rhinoceros than in R pheonicis while the reverse was the case for the values of crude fat, total carbohydrate and energy content. The crude protein content of both samples was high, with a value of 42.3 ± 0.84% for the palm beetle and 31.6 ± 0.59% for palm weevil, while crude fat was high (17.3 ± 1.2%) in palm weevil and very low (0.55 ± 0.10%) in palm beetle. The calorific value in kcal 100 g^?1 sample was 425 in R pheonicis and was significantly higher (p < 0.05) than the value of 285 in O rhinoceros, due to a relatively higher crude fat and total carbohydrate in the former compared with the latter. The mineral concentrations were high and differed for all the elements, with O rhinoceros having the higher level of many of the mineral elements (calcium, magnesium, potassium, manganese, iron and phosphorus) compared with R pheonicis, consistent with a significantly higher (p < 0.05) ash content of 12.7 ± 0.81% in O rhinoceros against the value of 4.2 ± 0.45% ash in R pheonicis. The amino acid profile showed both samples to be good sources of essential and non‐essential amino acids including cysteine and methionine, both of which contain sulfur. Valine, which had the lowest chemical score of 51.2%, was the most limiting amino acid for protein quality in both O rhinoceros and R pheonicis. Copyright © 2005 Society of Chemical Industry     

Development of a Novel Functional Soup Rich in Bioactive Sulforaphane Using Broccoli (Brassica oleracea L. ssp. italica) Florets and Byproducts

Broccoli florets are rich in health-promoting compounds such as glucoraphanin, the precursor of the bioactive compound sulforaphane. In addition, broccoli byproducts such as stalk also contain health-promoting compounds and represent attractive ingredients in the development of functional foods. The bioconversion of glucosinolates into bioactive isothiocyanates is affected by many factors including heat and therefore cooking of Brassica such as broccoli may result in significant loss of sulforaphane production. The aim of this study was to develop a suitable food system as a vehicle for the delivery of sulforaphane in the human diet in adequate quantities. To this end, the feasibility of dry-mix ready soup as a food matrix for the delivery of broccoli floret and byproducts was evaluated. In particular, this study investigated the bioconversion of glucosinolates into bioactive isothiocyanates during the cooking process of this novel food product by microwave heating. In addition to total isothiocyanate and sulforaphane content, other key physical and biochemical quality attributes of the broccoli floret- and byproduct-enriched soups were investigated. Total isothiocyanate and sulforaphane content in floret- and stalk-enriched soups was high in both cases and increased in the order stalk<floret. The overall acceptability of stalk containing soups was not significantly different compared with the control soups, whereas floret containing soups received significantly lower acceptability scores. These results suggest that ready soups prepared by microwave heating represent a feasible food product for the delivery of broccoli florets and byproducts which is compatible with the bioconversion of glucosinolates into bioactive isothiocyanates.