bluuebunny/crossref_metadata_2025_split huggingface dataset:
The Use of Internal Models: Comparison of the New Basel Credit Proposals with Available Internal Models for Credit Risk
Authors: Crouhy Michel , Galai Dan , Mark Robert 
Published: March 2007

AbstractThis chapter presents the New Capital Adequacy Accord proposed by the Basel Committee on Banking Supervision (Basel II) to replace the current 1988 Capital Accord (Basel I) by a more risk-sensitive framework for the measurement of credit risk. Basel II offers a menu of approaches: the “standardized” approach and the “internal ratings based” (IRB) approach with two variants: the “foundation” and the “advanced” approaches. These approaches are reviewed and their shortcomings are discussed. The standardized approach presents similar flaws to Basel I. The regulatory capital attribution according to the IRB approach is compared with the economic capital allocation from the industry-sponsored credit portfolio models, including CreditMetrics, KMV, and CreditRisk+. This comparison shows that the capital attribution for investment grade facilities from the IRB approach, although much lower than for the standardized approach, is still too high compared with the allocation from internal models. For subinvestment grade portfolios, the opposite is true where the IRB approach allocates more capital than the standardized approach, but still much less than the internal models. It is also noted that when the various credit portfolio models are calibrated with consistent parameters, they produce capital attributions that are relatively close to one another. It is clear from these conclusions that regulatory arbitrage will prevail as banks will be incentivized, as under Basel I, to shed away their high-quality assets through loan sales and securitization, and keep on their balance sheet the more risky loans for which regulatory capital underestimates the actual economic risk.
Enforcement of Risk‐Based Capital Rules
Authors: Wellons Philip A. 
Published: March 2007

AbstractThis chapter examines the role of enforcement for capital adequacy regulation in US banking and securities markets. Very little is known about how enforcement works: What broken rules are being enforced? By whom? How serious are the violations? How effective is enforcement, which presumably should discourage others from breaking important capital rules? The data are from enforcement actions over the last 6 to 10 years by US regulators, who are unique in publishing them. Even though the capital adequacy rules differ for banks and securities firms, the approaches to enforcing them overlap enough to allow rough comparison. This chapter finds a very low number of formal enforcement actions. Most target the small firms or individuals, not the big firms. Formal actions are particularly rare against the largest banks and securities firms, those that pose the greatest threat to the financial system. All but one of the capital adequacy violations resulted from fraud, theft, or other forms of operational risk. Only one resulted from credit risk. The chapter examines possible explanations of the findings, such as the relatively strong economy during much of the period and the possibility that very effective supervision catches almost all firms before their capital falls too low. Evidence from case studies of failed banks suggests that supervisors need to do a better job relating a bank's apparently adequate capital to its risk exposure, and to force banks to implement proposals regulators make to remedy deficiencies. Perhaps the very limited enforcement against large firms reflects a regulatory bias in their favor rather than their underlying strength and adequate capital.
Outcome after admission to ITU following out‐of‐hospital cardiac arrest: are non‐survivors suitable for non‐heart‐beating organ donation?
Authors: Gratrix Andrew P. , Pittard Alison J. , Bodenham Andrew R. 
Published: March 2007

SummaryWe have reviewed retrospective data from two large UK teaching hospitals regarding outcome following out‐of‐hospital cardiac arrest and the suitability of non‐survivors for non‐heart‐beating organ donation. Patients were selected retrospectively from consecutive admissions from two intensive care units who had presented following out‐of‐hospital cardiac arrest, to a total of 50 patients in each centre. They had all been resuscitated to achieve a spontaneous cardiac output at the scene, in transit or after arrival in hospital, and required further intensive care support due to cardiovascular, respiratory, or neurological impairment. Eighty‐six patients (86%) died in the Intensive Care Unit and only 14 (14%) survived to discharge from the Unit. A further nine (9%) patients died in hospital before discharge home. Four patients (4%) were alive after 6 months and three (3%) were alive after 1 year. Fifty‐seven (57%) of patients had active withdrawal of treatment with only four (4%) being potentially suitable for organ procurement having not been excluded because of age, medical history or the length of time to die following withdrawal of treatment. Our results show that only a small increase in donor organs could be potentially achieved from this population. Further work is required to determine whether such patients should be considered as non‐heart‐beating donors.
Behavioural treatment of severe food refusal in five toddlers with developmental disabilities
Authors: De Moor J. , Didden R. , Korzilius H. 
Published: March 2007

AbstractBackground  Young children with developmental disabilities are at risk of food refusal. In case of severe food refusal, children are being fed by nasal or gastrostomy tube. Behavioural treatment may be effective in establishing oral food intake.Methods  A behavioural treatment package was implemented in an outpatient setting for the treatment of severe food refusal in five toddlers with developmental disabilities. During the course of treatment, treatment principles were generalized to parents in the home setting.Results  Treatment resulted in oral acceptance of a variety of food items in each child and was successfully generalized. Treatment effects were maintained during follow‐up between 3 and 12 months. Tube feeding was discontinued in each child and health status of each child improved.Conclusions  Behavioural treatment may be highly effective in establishing oral food intake in children with developmental disabilities (in the absence of organic causes). As a side‐effect of this treatment, tube‐feeding may be discontinued and general heath status improved.
Nurses’ experiences of caring for families with relatives in intensive care units
Authors: Stayt Louise Caroline 
Published: March 2007

AbstractAim.  This paper reports an exploratory study of nurses’ experiences of caring for families who have relatives in adult intensive care units.Background.  The admission of a critically ill patient into adult intensive care is universally accepted as a crisis for both patients and their families. Family members of critically ill people may experience emotional turmoil and therefore have many needs throughout the course of the relative’s illness. It has been identified that nurses are best placed to meet families’ needs. Whilst there is a substantial evidence base associated with family needs, little is known about nurses’ experiences of caring for these families.Method.  Interviews, informed by Heideggerian philosophy, were conducted with a purposive sample of 12 Registered Nurses working in an adult intensive care unit. Interview transcripts were analysed using Colaizzi's framework. The data were collected in Autumn 2005.Findings.  Participants’ experiences were categorized into the following themes: defining the nurse's role, role expectations and role conflict. Participants reported lack of confidence, doubts about their professional competence and conflicts between their professional and personal self. These experiences were linked to participants’ expectations and self‐imposed standards.Conclusion.  Registered Nurses caring for families who have relatives in adult intensive care units face a fundamental conflict both between role expectations and patient care and between professional ideals and being a human. This not only highlights a disparity between nurses everyday family care practice and the underpinning theories but also may contribute to occupational stress.
Effects of herbicide spray drift and fertilizer overspread on selected species of woodland ground flora: comparison between short‐term and long‐term impact assessments and field surveys
Authors: GOVE B. , POWER S. A. , BUCKLEY G. P. , GHAZOUL J. 
Published: March 2007

Summary

Although application of fertilizers and pesticides to farmland is known to impact non‐target organisms in adjacent semi‐natural habitats, little is known of the impact on woodland understorey communities, which have considerable conservation significance in the arable landscapes of the UK and elsewhere in Europe. This study investigated the impacts of agrichemicals on several plant species typically found in ancient semi‐natural communities.
Six species of woodland plants were exposed to the herbicide glyphosate at concentrations equivalent to those measured in spray drift trials (1–25% of the full application rate) in short‐term greenhouse and long‐term field experiments. Fertilizer was applied to half of the plants at a concentration likely to be seen in overspread situations (70 kg ha−1 year−1). The distribution of the same species was surveyed in woodland margins adjacent to fields with high, medium and low agrichemical inputs.
In both greenhouse and field experiments, herbicide treatments at drift concentrations caused increased mortality, reduced biomass and reduced fecundity in all species, although to differing degrees. The threshold of sensitivity to glyphosate was as low as 1% of the median field application rate for the most sensitive species. Fertilizer treatment affected resource partitioning in Carex remota and Galium odoratum and reduced the fecundity of G. odouratum.
In field surveys, the abundance of the most sensitive species was highest in woodland margins adjacent to fields with low agrichemical inputs and lowest beside high‐input farmland. These differences were seen at least 4 m into woodland margins but were not found at 10 m.
Synthesis and applications. There was considerable agreement between the short‐term greenhouse and long‐term field experiments, although long‐term impacts may have been underestimated in the former. Adverse impacts of pesticide drift have been demonstrated to affect a variety of plants of woodland margins bordering farmland. Differences in the distribution of species most sensitive to herbicide extend to at least 4 m into woodland margins. We recommend the adoption of no‐spray buffer zones of at least 5 m to protect the majority of woodland species from the impacts of agrichemicals applied to adjacent land.
Population dynamics and responses to management of plateau pikas Ochotona curzoniae
Authors: PECH ROGER P. , JIEBU  , ARTHUR ANTHONY D. , YANMING ZHANG , HUI LIN 
Published: March 2007

Summary

Plateau pikas Ochotona curzoniae are considered a pest species on the Tibetan Plateau because they compete with livestock for forage and their burrowing could contribute to soil erosion. The effectiveness of pest control programmes in Tibet has not been measured, and it is not known whether changes in livestock management have exacerbated problems with plateau pikas or compromised their control. This study measured the impact of control programmes and livestock management for forage conservation on populations of plateau pikas in alpine meadow in Naqu District, central Tibet, during 2004 and 2005.
Current techniques for controlling plateau pikas in spring cause large reductions in abundance, but high density‐dependent rates of increase result in no differences between treated and untreated populations by the following autumn. Rates of increase from spring to autumn are not influenced by standing plant biomass or concurrent grazing by yaks Bos grunniens and Tibetan sheep Ovis aries.
In autumn there was significantly lower biomass outside fenced areas with year‐round livestock grazing compared with inside fenced areas with equivalent or higher numbers of plateau pikas but predominantly winter grazing by livestock. Inside fenced areas, control of plateau pikas in spring produced no detectable effect on standing plant biomass at the end of the following summer compared with uncontrolled populations of plateau pikas.
Regardless of their initial density, populations of plateau pikas declined rapidly over winter outside fenced areas where there was very low standing plant biomass in autumn. However, inside fenced areas with higher plant biomass in autumn, low‐density populations of plateau pikas declined more slowly than high‐density populations.
Synthesis and applications. Current control programmes have limited effect because populations of plateau pikas can recover in one breeding season. There was no apparent increase in forage production in areas where plateau pikas were controlled. However, plateau pikas appear to benefit from changes in grazing management, with low‐density populations declining less over winter inside fenced areas than elsewhere. It was not evident that control programmes are warranted or that they will improve the livelihoods of Tibetan herders.
An NB‐LRR protein required for HR signalling mediated by both extra‐ and intracellular resistance proteins
Authors: Gabriëls Suzan H.E.J. , Vossen Jack H. , Ekengren Sophia K. , Ooijen Gerben van , Abd‐El‐Haliem Ahmed M. , Berg Grardy C.M. van den , Rainey Daphne Y. , Martin Gregory B. , Takken Frank L.W. , Wit Pierre J.G.M. de , Joosten Matthieu H.A.J. 
Published: March 2007

SummaryTomato (Solanum lycopersicum) Cf resistance genes confer hypersensitive response (HR)‐associated resistance to strains of the pathogenic fungus Cladosporium fulvum that express the matching avirulence (Avr) gene. Previously, we identified an Avr4‐responsive tomato (ART) gene that is required for Cf‐4/Avr4‐induced HR in Nicotiana benthamiana as demonstrated by virus‐induced gene silencing (VIGS). The gene encodes a CC‐NB‐LRR type resistance (R) protein analogue that we have designated NRC1 (NB‐LRR protein required for HR‐associated cell death 1). Here we describe that knock‐down of NRC1 in tomato not only affects the Cf‐4/Avr4‐induced HR but also compromises Cf‐4‐mediated resistance to C. fulvum. In addition, VIGS using NRC1 in N. benthamiana revealed that this protein is also required for the HR induced by the R proteins Cf‐9, LeEix, Pto, Rx and Mi. Transient expression of NRC1D481V, which encodes a constitutively active NRC1 mutant protein, triggers an elicitor‐independent HR. Subsequently, we transiently expressed this auto‐activating protein in N. benthamiana silenced for genes known to be involved in HR signalling, thereby allowing NRC1 to be positioned in an HR signalling pathway. We found that NRC1 requires RAR1 and SGT1 to be functional, whereas it does not require NDR1 and EDS1. As the Cf‐4 protein requires EDS1 for its function, we hypothesize that NRC1 functions downstream of EDS1. We also found that NRC1 acts upstream of a MAP kinase pathway. We conclude that Cf‐mediated resistance signalling requires a downstream NB‐LRR protein that also functions in cell death signalling pathways triggered by other R proteins.
Regulation and functional analysis of ZmDREB2A in response to drought and heat stresses in Zea mays L
Authors: Qin Feng , Kakimoto Masayuki , Sakuma Yoh , Maruyama Kyonoshin , Osakabe Yuriko , Tran Lam‐Son Phan , Shinozaki Kazuo , Yamaguchi‐Shinozaki Kazuko 
Published: March 2007

SummaryDREB1/CBFs and DREB2s are transcription factors that specifically interact with a cis‐acting element, DRE/CRT, which is involved in the expression of genes responsive to cold and drought stress in Arabidopsis thaliana. The function of DREB1/CBFs has been precisely analyzed and it has been found to activate the expression of many genes responsive to cold stress containing a DRE/CRT sequence in their promoters. However, the regulation and function of DREB2‐type transcription factors remained to be elucidated. In this research, we report the cloning of a DREB2 homolog from maize, ZmDREB2A, whose transcripts were accumulated by cold, dehydration, salt and heat stresses in maize seedlings. Unlike Arabidopsis DREB2A, ZmDREB2A produced two forms of transcripts, and quantitative real‐time PCR analyses demonstrated that only the functional transcription form of ZmDREB2A was significantly induced by stresses. Moreover, the ZmDREB2A protein exhibited considerably high transactivation activity compared with DREB2A in Arabidopsis protoplasts, suggesting that protein modification is not necessary for ZmDREB2A to be active. Constitutive or stress‐inducible expression of ZmDREB2A resulted in an improved drought stress tolerance in plants. Microarray analyses of transgenic plants overexpressing ZmDREB2A revealed that in addition to genes encoding late embryogenesis abundant (LEA) proteins, some genes related to heat shock and detoxification were also upregulated. Furthermore, overexpression of ZmDREB2A also enhanced thermotolerance in transgenic plants, implying that ZmDREB2A may play a dual functional role in mediating the expression of genes responsive to both water stress and heat stress.
Soya Bean (Glycine max L. Merr.) Genotype Response to Early‐season Flooding: II. Aboveground Growth and Biomass
Authors: Henshaw T. L. , Gilbert R. A. , Scholberg J. M. S. , Sinclair T. R. 
Published: March 2007

AbstractSoya bean is often grown in regions prone to periodic flooding, thus selecting cultivars that maintain production under waterlogged conditions is desirable. An experiment involving flooded soya beans was planted in southern Florida to examine (1) stem and leaf growth; (2) morphological adaptations; and (3) the relationship between early‐season and late‐season flood tolerance in flooded soya beans. Eleven soya bean genotypes previously defined as tolerant or sensitive to flooding were subjected to three treatments at 21 days after sowing (DAS): (1) no flood, (2) 2‐week flood and (3) 4‐week flood. All plants were harvested 49 DAS. Flooded plants exhibited lower stem dry weights but greater partitioning to the stem. Non‐flood treatments had greater leaf dry weight, leaf area and partitioning to leaves than flooded plants. There were positive correlations of genotype stem dry weight and leaf dry weight to early‐season flood tolerance but stem partitioning was negatively correlated with early‐season flood tolerance. Genotypic rankings of early‐season flood tolerance in this study were not correlated with earlier studies basing flood tolerance on seed yield. Our study highlights the range of soya bean morphological adaptations in response to flood. However, our results indicate that early‐season screening may not be an accurate predictor of soya bean genotypic response to late‐season flood.
Maximum Likelihood Inference On A Mixed Conditionally and Marginally Specified Regression Model for Genetic Epidemiologic Studies with Two-Phase Sampling
Authors: Chatterjee Nilanjan , Chen Yi-Hau 
Published: March 2007

SummaryTwo-phase stratified sampling designs can reduce the cost of genetic epidemiologic studies by limiting expensive ascertainments of genetic and environmental exposure to an efficiently selected subsample (phase II) of the main study (phase I). Family history and some covariate information, which may be cheaply gathered for all subjects at phase I, can be used for sampling of informative subjects at phase II. We develop alternative maximum likelihood methods for analysis of data from such studies by using a novel regression model that permits the estimation of ‘marginal’ risk parameters that are associated with the genetic and environmental covariates of interest, while simultaneously characterizing the ‘conditional’ risk of the disease associated with family history after adjusting for the other covariates. The methods and appropriate asymptotic theories are developed with and without an assumption of gene–environment independence, allowing the distribution of the environmental factors to remain non-parametric. The performance of the alternative methods and of sampling strategies is studied by using simulated data involving rare and common genetic variants. An application of the methods proposed is illustrated by using a case–control study of colorectal adenoma embedded within the prostate, lung, colorectal and ovarian cancer screening trial.
On the Non-Negative Garrotte Estimator
Authors: Yuan Ming , Lin Yi 
Published: March 2007

SummaryWe study the non-negative garrotte estimator from three different aspects: consistency, computation and flexibility. We argue that the non-negative garrotte is a general procedure that can be used in combination with estimators other than the original least squares estimator as in its original form. In particular, we consider using the lasso, the elastic net and ridge regression along with ordinary least squares as the initial estimate in the non-negative garrotte. We prove that the non-negative garrotte has the nice property that, with probability tending to 1, the solution path contains an estimate that correctly identifies the set of important variables and is consistent for the coefficients of the important variables, whereas such a property may not be valid for the initial estimators. In general, we show that the non-negative garrotte can turn a consistent estimate into an estimate that is not only consistent in terms of estimation but also in terms of variable selection. We also show that the non-negative garrotte has a piecewise linear solution path. Using this fact, we propose an efficient algorithm for computing the whole solution path for the non-negative garrotte. Simulations and a real example demonstrate that the non-negative garrotte is very effective in improving on the initial estimator in terms of variable selection and estimation accuracy.
On Fast Computation of the Non-Parametric Maximum Likelihood Estimate of a Mixing Distribution
Authors: Wang Yong 
Published: March 2007

SummaryA fast algorithm for computing the non-parametric maximum likelihood estimate of a mixing distribution is presented. At each iteration, the algorithm adds new important points to the support set as guided by the gradient function, updates all mixing proportions via a quadratically convergent method and discards redundant support points straightaway. With its convergence being theoretically established, numerical studies show that it is very fast and stable, compared with several other algorithms that are available in the literature.
Probabilistic Forecasts, Calibration and Sharpness
Authors: Gneiting Tilmann , Balabdaoui Fadoua , Raftery Adrian E. 
Published: March 2007

SummaryProbabilistic forecasts of continuous variables take the form of predictive densities or predictive cumulative distribution functions. We propose a diagnostic approach to the evaluation of predictive performance that is based on the paradigm of maximizing the sharpness of the predictive distributions subject to calibration. Calibration refers to the statistical consistency between the distributional forecasts and the observations and is a joint property of the predictions and the events that materialize. Sharpness refers to the concentration of the predictive distributions and is a property of the forecasts only. A simple theoretical framework allows us to distinguish between probabilistic calibration, exceedance calibration and marginal calibration. We propose and study tools for checking calibration and sharpness, among them the probability integral transform histogram, marginal calibration plots, the sharpness diagram and proper scoring rules. The diagnostic approach is illustrated by an assessment and ranking of probabilistic forecasts of wind speed at the Stateline wind energy centre in the US Pacific Northwest. In combination with cross-validation or in the time series context, our proposal provides very general, nonparametric alternatives to the use of information criteria for model diagnostics and model selection.