bluuebunny/crossref_metadata_2025 huggingface dataset:
Glomus Tumor of the Duodenum
Authors: Jundi Majd , Lack Ernest E. , Brun Erwin A. , Esquivel Jesus , Kumar Dhruv
Published: April 2006

We describe a rare case of glomus tumor of the duodenum. The tumor was detected in a 46-year-old man being investigated for episodes of gastrointestinal bleeding. The excised specimen showed a 2.3 × 1.5 × 1.5 cm gray-tan tumor involving the mucosa and the submucosa. The overlying mucosa was focally ulcerated. Histologically, the tumor had a solid pattern of sharply demarcated, round glomus cells with prominent pericytoma-like vessels of varying sizes. The neoplastic cells stained for vimentin, smooth muscle actin, and focally for synaptophysin. These histologic and immunohistochemical features are consistent with a diagnosis of glomus tumor of the duodenum.
What Is the Empirical Basis for Paying for Quality in Health Care?
Authors: Rosenthal Meredith B. , Frank Richard G.
Published: April 2006

Despite more than a decade of benchmarking and public reporting of quality problems in the health care sector, changes in medical practice have been slow to materialize. To accelerate quality improvement, many private and public payers have begun to offer financial incentives to physicians and hospitals based on their performance on clinical and service quality measures. The authors review the empirical literature on paying for quality in health care and comparable interventions in other sectors. They find little evidence to support the effectiveness of paying for quality. The absence of findings for an effect may be attributable to the small size of the bonuses studied and the fact that payers often accounted for only a fraction of the targeted provider's panel. Even in nonhealth settings, however, where the institutional features are more favorable to a positive impact, the literature contains mixed results on the effectiveness of analogous pay-for-performance schemes.
Bureaucratic Policy Making on Trial: Medicaid Nursing Facility Reimbursement, 1988-1998
Authors: Miller Edward Alan
Published: April 2006

Few systematically assess the determinants of Medicaid nursing facility reimbursement. Consequently, this article examines what factors influenceprogram administrators’decisions regarding nursing facility cost report data—the basic information states use to establish payment. Whereas elected officials focus primarily on how much is spent on nursing homes, state Medicaid officials assume primary responsibility for the esoteric and highly technical dimensions that help make spending goals a reality. Findings indicate that the federal government influenced state policy by enabling provider litigation under the Boren Amendment. They also indicate that program administrators responded rationally to fiscal and economic concerns, and that states with stronger administrative capacity were better able to overcome obstacles to sustaining desired policies. Although results reveal that states with more powerful nursing home lobbies tended to implement more generous systems, they fail to reveal significant associations between cost report year and lobbying activity on behalf of the elderly.
Note. 1-MCP Effect on Chilling Injury Development in ‘Nova’ and ‘Ortanique’ Mandarins
Authors: Salvador A. , Carvalho C. P. , Monterde A. , Martìnez-Jávega J. M.
Published: April 2006

The aim of this work was to evaluate the effect of 1-methylcyclopropene (1-MCP) on chilling injury (CI) incidence, ethylene production, phenylalanine ammonia-lyase (PAL) activity and quality changes on mandarin hybrids, ‘Nova’ and ‘Ortanique’, during cold storage. Fruits were treated for 24h with 1-MCP at 0.5 L/L and then stored at 1 ºC. 1-MCP markedly reduced CI incidence in both cultivars, this effect being more accentuated in ‘Nova’ mandarins, which presented lower tolerance to cold storage. 1-MCPtreated fruit presented less PAL activity parallel to a significant increase in ethylene production. These results suggested that ethylene played an important role in citrus fruit CI development and 1-MCPinduced ethylene production might act as a protector of the fruit against chilling damage. 1-MCP reduced ethanol concentration slightly decreased CO2 production and had no effect on fruit quality characteristics such as TSS, acid content or texture for both cultivars.
Note. Low Molecular Weight Carbohydrates in Foods Usually Consumed in Spain
Authors: Espinosa-Martos I. , Rico E. , Rupèrez P.
Published: April 2006

Low molecular weight carbohydrates (LMWC) were determined in foods usually consumed in Spain, namely: rice, biscuits, white bread, noodles, honey, as well as the most common vegetables of the Mediterranean diet. LMWC in foods contained mono-, di- and oligosaccharides; soluble sugars ranged from 0.2% to 83.8% in rice and honey, respectively. All samples contained different amounts of sucrose, glucose and fructose, except for garlic that only contained sucrose (2.4%). Inulin was high in garlic (13.5%), followed by onion (1.4%) and globus artichoke (0.5%). Minor inulin contents were detected in biscuits (0.2%) and a trace in noodles, white bread and endives. Non-digestible oligosaccharides (NDO) detected in the samples ranged from 12% honey, 3.2% garlic, 3.7% onion, 1.3% globus artichoke and minor amounts in noodle, endive, biscuit and white bread. According to the determined LMWC contents and the current intake of these foods in Spain, the amount of mono- and disaccharide would be 4.3 kg/person/year, while that of inulin plus non-digestible oligosaccharides, 0.4 kg/person/year. Thus, the estimated daily intake of the potential prebiotics inulin plus NDO from the foods selected was 1.1 g/person.
Application of Chitosan Films Enriched with Oregano Essential Oil on Bologna – Active Compounds and Sensory Attributes
Authors: Chi S. , Zivanovic S. , Penfield M. P.
Published: April 2006

Chitosan films prepared with oregano essential oil were applied on bologna slices. Release of the essential oil compounds during film preparation and application on the meat product and consumer acceptability of bologna enriched with oregano essential oil were tested. Oregano essential oil compounds were quantified by gas chromatography mass spectroscopy (GCMS) after extraction from the filmforming solution, films before and after application on bologna and from bologna slices before and after application of the films. The results indicated that the concentration of components of the essential oil sharply decreased during film preparation, e.g. from 757.7 ppm carvacrol in film-forming solution to 2.1 ppm in dried films. No carvacrol was detected in the films after application on bologna for 5 days at 4°C, mainly due to its diffusion into bologna. It seemed that the moisture and high lipid content of bologna helped the diffusion of the oregano essential oil from the chitosan film matrix into the product. Sensory evaluation suggested that addition of 45 ppm or less of oregano oil to bologna would be acceptable to consumers. Results support the potential use of chitosan–oregano essential oil films as an antimicrobial packaging material for processed meat.
Comparative Evaluation of Regenerative Capacity of Different Adsorbents and Filters for Degraded Frying Oil
Authors: Phogat S. S. , Mittal G. S. , Kakuda Y.
Published: April 2006

The quality of degraded frying oil using Magnasol and Filtrite adsorbents was evaluated. Level of adsorbents (1%, 2% and 3%), treatment duration (2min, 5min and 8min) and temperature (60°C and 160°C) were the processing variables considered. The maximum improvement was up to an extent of 7.0% to 8.8%, 15.2% to 18%, 11.7% to 14.6% and 4.5% to 5.9% for capacitance (C), viscosity (μ), photometric colour index (PCI) and free fatty acids (FFAs), respectively. Specific gravity (γ) and colour parameters (L*, a*, b* and ΔE*) showed no significant difference due to treatments. The interaction of temperature and adsorbent level showed a more pronounced effect. The use of an adsorbent with different filters in a device, used at the food service establishment to filter oil under high-pressure, improved oil quality except for FFAs. The maximum reduction in C, γ, PCI and FFAs varied between 5.1% to 42.6%, 7.4% to 33.3%, 7.8% to 62.7% and 0.5% to 4.4%, respectively, depending upon filtration treatment. Colour parameters and γ were not affected. Polishing of oil by circulating it through the device for up to 30min also provided improvement in γ, C, μ, PCI and FFAs in the ranges of 0.18–0.40%, 19.3–27.2%, 16.0–23.7%, 28.7–42.9% and 1.1–2.2%, respectively. The combination of active and passive filtration systems has good prospects for oil quality improvement.
Effect of Meat Piece, Packaging and Storage on pH, Thiobarbituric Acid Reactive Substances and Microbial Counts in Broilers Fed Diets Supplemented with Ram Horn Hydrolysate
Authors: Aksu M. I. , Karaoglu M. , Esenbuga N. , Kaya M. , Macit M.
Published: April 2006

This research was carried out to determine the effects of meat piece, packaging type and storage time on the pH, thiobarbituric acid reactive substances (TBARS), total mesophilic, total psychrotrophic, lactic acid and Enterobacteriaceae counts at 0, 2, 4, 6, 8, 10 and 12 days of storage, in broilers fed diets containing 0% (H0), 1% (H1), 2% (H3) and 3% (H3) levels of ram horn hydrolisate (RHH) in daily water requirements of chicks during experimental periods. A total of 240 male broiler chicks ( Ross-308) were allocated to four dietary treatments (H0, H1, H2 and H3 groups) in a completely randomized experimental design. RHH-added water and feed were offered ad libitum consumption for the first 28 days of the experiment; and then they were fed only a basal diet and normal drinking water to the end of the study. At the end of the trial all the birds were slaughtered, then standard dissection of carcasses, breasts and drumsticks were divided into two groups for vacuum and aerobic packaging. Packed breasts and drumsticks were stored at 3 ± 0.5°C for 12 days, and the pH, TBARS and microbial counts were determined during the storage period. The use of ram horn hydrolysate at 1% and 3% levels in broiler diets increased pH values of breast fillets and drumstick meats ( p < 0.01). TBARS value ( p < 0.01) and Enterobacteriaceae counts ( p < 0.01) decreased compared to the control group. pH, TBARS and Enterobacteriaceae counts were lower ( p < 0.05) in breast fillets than drumstick muscles. The pH, TBARS and bacteria counts increased during storage ( p < 0.01). The vacuum packaging preserved the meat quality properties of broiler breast fillets and drumsticks meats ( p < 0.05). The results obtained from the present study, concluded that the use of ram horn hydrolysate in broiler diet decreased lipid oxidation of the broiler breast and drumstick meats, and the level of Enterobacteriaceae was also reduced in vacuum packed samples during the storage period.
Reactions to Positive Deviance: Social Identity and Attribution Dimensions
Authors: Fielding Kelly S. , Hogg Michael A. , Annandale Nicole
Published: April 2006

This research examines whether evaluations of positive deviates (i.e. high achieving group members) are influenced by the attributions they make for their performance. We argue that ingroup positive deviates who make group attributions help enhance the ingroup's image and thus attract favorable evaluations. In Experiment 1, ingroup positive deviates who made group attributions were generally evaluated more favorably than ingroup positive deviates who made individual attributions. There was also evidence that the positive deviates' attribution style influenced group and self-evaluations. Evaluations of outgroup positive deviates were not influenced by their attribution style. In Experiment 2, an ingroup positive deviate who was successful and attributed that success to the group was upgraded relative to an ingroup positive deviate who made individual attributions. Group evaluations were also higher when the positive deviate made group attributions. This pattern did not emerge when the positive deviate failed. The results are discussed from a social identity perspective.
Motivated Entitativity: Applying Balance Theory to Group Perception
Authors: Pilialoha Brian R. U. , Brewer Marilynn B.
Published: April 2006

The focus of the current work is on the motivated aspects of entitativity using the perspective gained from theories of cognitive consistency. The central hypothesis is that balance principles will motivate perceivers to partition the social world in such a way as to achieve a state of consistency between social units and attributed acts. Three studies are reported: one employing content analytic methods to investigate motivated perceptions of the US Supreme Court in the context of the 2000 presidential election, and two laboratory experiments. Results generally supported the prediction that agreement with a court's decision would lead to perceiving the court as an entitative unit, whereas disagreement would lead to ‘de-entifying' the court by differentiating individual members or subgroups. Alternative explanations and implications of these findings for motivated cognition are discussed.
Predictors of Cultural Adjustment: Intergroup Status Relations and Boundary Permeability
Authors: Terry Deborah J. , Pelly Rebecca N. , Lalonde Richard N. , Smith Joanne R.
Published: April 2006

We examined intergroup predictors of cultural adjustment among Asian international students in Australia. Sociostructural beliefs (status, legitimacy, and permeability) and initial adjustment were assessed ( N= 113) at Time 1, and measures of adjustment were obtained ( N= 80) at Time 2 eight weeks later. International students who perceived their cultural group to be relatively low in status experienced lower levels of psychological adjustment. Also, as expected, the effects of status were moderated by perceptions of both the permeability of intergroup boundaries and the legitimacy of the status differential. At high levels of legitimacy, perceptions of permeable group boundaries were associated with better psychological, sociocultural, and academic adjustment among international students perceiving their group to be low in status, but lower levels of adjustment among students who perceived their group to be high in status. At low levels of legitimacy, irrespective of group status position, perceived permeability was not related to adjustment.
Identity and Adaptation Among Minority Indo-Guyanese: Influence of Generational Status, Gender, Reference Group and Situation
Authors: Clément Richard , Singh Sonia S. , Gaudet Sophie
Published: April 2006

The impact of ethnic reference group, situational characteristics, generational status, and gender on ethnic identification in relation to adaptation was studied in Indo-Guyanese immigrants living in Ottawa, Canada. Ninety-eight first-( n= 48) and second-generation ( n= 50) participants completed a questionnaire in reference to their East-Indian ancestral group, their ingroup and the national Canadian group. Results show that identification was the product of a complex interaction among reference group, situation, generation and gender. The pattern of adaptation to each reference group was influenced by generational status, and greater identification with the Canadian group relative to the Guyanese group was related to positive relations with the Canadian group. The results are discussed within the context of current theories of acculturation and intergroup relations.
Factors characterizing bursts of figurative language and gesture in college lectures
Authors: Corts Daniel P.
Published: April 2006

In an analysis of three college lectures, Corts and Pollio (1999) found that figurative language and gesture often appeared together in ‘bursts’. These bursts were initially characterized as novel figurative expression that centered on the primary topic of the lecture. The current study is an attempt to provide clearer description of how and why figurative language and gesture so often appear together in academic discourse. In addition, this study extends earlier findings to additional speakers and academic disciplines to improve generalizability. In accordance with Corts and Pollio, the bursts of figurative activity are predominately novel rather than cliched, coherent with a root metaphor, and centered around the main topics of the lecture. The present study adds that figures within bursts largely include analogies and metaphor that represent a concept whereas topical figures outside of bursts are descriptive phrases that often include other types of figures such as hyperbole, litote, etc. The regularity of such bursts suggests that they serve an important cognitive function independent of personal style of the lecturer or any demands of a particular academic field.
The distribution of discoursal salience in research papers: relational hypotaxis and parataxis
Authors: Golebiowski Zofia
Published: April 2006

In this article I challenge the claim that nuclearity is a central principle in the organization of texts. I propose the Framework for the Relational Analysis of Texts (FARS) which accounts for the paratactic and hypotactic realization of coherence relations. Within this framework, the taxis of coherence relations is co-textually dictated. I consider the writer choices in the distribution of discoursal salience and the intertextual and intercultural variation of these choices. It is suggested that divergence between approaches that perceive text as exhibiting both hypotactic and paratactic organization and those that see nuclearity as a basic characteristic of text structure arises from differences in the linguistic corpora examined during the construction of respective theoretical frameworks.
Making sequentiality salient: and-prefacing in the talk of airline pilots
Authors: Nevile Maurice
Published: April 2006

This article uses transcriptions from video recordings of airline pilots at work, on actual flights, to consider some locations and the interactional significance of a feature of routine talk in the airline cockpit: and-prefaced turns. As pilots’ work is formally organized for them as many discrete and ordered tasks, and-prefacing is a local means for maintaining an ongoing sense of their conduct of a flight as a whole. By and-prefacing their talk, pilots present some new talk or task as connected and relevantly next in a larger macro-sequence of work for their flight. And-prefacing is evidence of pilots’ orientation to a sense of sequence that can extend well beyond pairs of turns at talk and/or non-talk activities, or even a series of such paired sequences. It allows pilots to make salient the sequentiality of their work where the officially prescribed wordings they must use can leave this implicit.
Relational Spatial Reasoning by a Nonhuman: The Example of Capuchin Monkeys
Authors: Fragaszy Dorothy M. , Cummins-Sebree Sarah E.
Published: April 2006

The authors review spontaneous manipulation and spatial problem solving by capuchin monkeys to illuminate the nature of relational reasoning (wherein two or more elements of a problem or situation are considered together to arrive at a course of action) that these monkeys use in goal-directed activity. Capuchin monkeys master problems with one, two, or three spatial relations, and if more than one relation, at least two relations may be managed concurrently. They can master static and dynamic relations and, with sufficient practice, can produce specific spatial relations through both direct and distal action. Examining capuchins' spatial problem-solving behavior with objects in the framework of a spatial relational reasoning model leads to new interpretations of previous studies with these monkeys and other nonhuman animals. The model produces a variety of testable predictions concerning the contribution of relational properties to spatial reasoning. It also provides conceptual linkages with neurological processes and cognitive analyses of physical reasoning. Understanding relational spatial reasoning, including tool use, in a wider view is vital to informed, principled comparison of problem solving and the use of technology across species, across ages within species, and across eras in human prehistory.
The dead leaves model: a general tessellation modeling occlusion
Authors: Bordenave Charles , Gousseau Yann , Roueff François
Published: April 2006

In this article, we study a particular example of general random tessellation, the dead leaves model. This model, first studied by the mathematical morphology school, is defined as a sequential superimposition of random closed sets, and provides the natural tool to study the occlusion phenomenon, an essential ingredient in the formation of visual images. We generalize certain results of G. Matheron and, in particular, compute the probability of n compact sets being included in visible parts. This result characterizes the distribution of the boundary of the dead leaves tessellation.
Central limit theorems for functionals of stationary germ-grain models
Authors: Pantle Ursa , Schmidt Volker , Spodarev Evgueni
Published: April 2006

Conditions are derived for the asymptotic normality of a general class of vector-valued functionals of stationary Boolean models in the d-dimensional Euclidean space, where a Lindeberg-type central limit theorem for m-dependent random fields, m ∈ N, is applied. These functionals can be used to construct joint estimators for the vector of specific intrinsic volumes of the underlying Boolean model. Extensions to functionals of more general germ–grain models satisfying some mixing and integrability conditions are also discussed.
Spinning plates and squad systems: policies for bi-directional restless bandits
Authors: Glazebrook K. D. , Kirkbride C. , Ruiz-Hernandez D.
Published: April 2006

This paper concerns two families of Markov decision problem that fall within the family of (bi-directional) restless bandits, an intractable class of decision processes introduced by Whittle. Thespinning plates problemconcerns the optimal management of a portfolio of reward-generating assets whose yields grow with investment but otherwise tend to decline. In the model of asset exploitation called thesquad system, the yield from an asset tends to decline when it is used but will recover when the asset is at rest. In all cases, simply stated conditions are given that guarantee indexability of the problem, together with conditions necessary and sufficient for its strict indexability. The index heuristics for asset activation that emerge from the analysis are assessed numerically and found to perform very strongly.
An inhomogeneous semi-Markov model for the term structure of credit risk spreads
Authors: Vasileiou Aglaia , Vassiliou P.-C. G.
Published: April 2006

We model the evolution of the credit migration of a corporate bond as an inhomogeneous semi-Markov chain. The valuation of a defaultable bond is done with the use of the forward probability of no default up to maturity time. It is proved that, under the forward probability measure, the semi-Markov property is maintained. We find the functional relationships between the forward transition probability sequences and the real-world probability sequences. The stochastic monotonicity properties of the inhomogeneous semi-Markov model, which play a prominent role in these issues, are studied in detail. Finally, we study the term structure of credit spread, provide an algorithm for the estimation of the forward probabilities of transitions under the risk premium assumptions, and present an estimation method for the real-world probability sequences.
Asymptotic behavior of a general class of mixture failure rates
Authors: Finkelstein Maxim , Esaulova Veronica
Published: April 2006

Mixtures of increasing failure rate distributions can decrease, at least in some intervals of time. Usually this property is observed asymptotically, as t → ∞, which is due to the fact that a mixture failure rate is ‘bent down’, as the weakest populations are dying out first. We consider a survival model that generalizes additive hazards models, proportional hazards models, and accelerated life models very well known in reliability and survival analysis. We obtain new explicit asymptotic relations for a general setting and study specific cases. Under reasonable assumptions we prove that the asymptotic behavior of the mixture failure rate depends only on the behavior of the mixing distribution in the neighborhood of the left-hand endpoint of its support, and not on the whole mixing distribution.
A Central Limit Theorem for Non-Overlapping Return Times
Authors: Johnson Oliver
Published: April 2006

Define the non-overlapping return time of a block of a random process to be the number of blocks that pass by before the block in question reappears. We prove a central limit theorem based on these return times. This result has applications to entropy estimation, and to the problem of determining if digits have come from an independent, equidistributed sequence. In the case of an equidistributed sequence, we use an argument based on negative association to prove convergence under conditions weaker than those required in the general case.
Monte Carlo Algorithms for Finding the Maximum of a Random Walk with Negative Drift
Authors: Baringhaus Ludwig , Grübel Rudolf
Published: April 2006

We discuss two Monte Carlo algorithms for finding the global maximum of a simple random walk with negative drift. This problem can be used to connect the analysis of random input Monte Carlo algorithms with ideas and principles from mathematical statistics.
An Explicit Formula for the Optimal Gain in the Full-Information Problem of Owning a Relatively Best Object
Authors: Mazalov Vladimir V. , Tamaki Mitsushi
Published: April 2006

A full-information version of the secretary problem in which the objective is to maximize the time of possession of a relatively best object is considered both in the case in which only the most recently observed object may be chosen and in the case in which any of the previously observed objects may be chosen. The main purpose of this paper is to obtain, under an optimal rule, both the asymptotic proportional durations when the number of objects tends to infinity, and the expected durations when the number of objects remains finite. The integral expressions for these asymptotic values are derived in both cases: the approximate numerical values are 0.435 in the former (no-recall) case and 0.449 in the latter (recall) case, indicating a surprisingly small difference. The expected values of the optimal stopping times are also obtained from the planar Poisson process analysis.
A Note on the Extremal Index for Space-Time Processes
Authors: Turkman K. F.
Published: April 2006

Let {X(s,t),s= (s1,s2) ∈ ℝ2,t∈ ℝ} be a stationary random field defined over a discrete lattice. In this paper, we consider a set of domain of attraction criteria giving the notion of extremal index for random fields. Together with the extremal-types theorem given by Leadbetter and Rootzen (1997), this will give a characterization of the limiting distribution of the maximum of such random fields.
Gambling Teams and Waiting Times for Patterns in Two-State Markov Chains
Authors: Glaz Joseph , Kulldorff Martin , Pozdnyakov Vladimir , Steele J. Michael
Published: April 2006

Methods using gambling teams and martingales are developed and applied to find formulae for the expected value and the generating function of the waiting time to observation of an element of a finite collection of patterns in a sequence generated by a two-state Markov chain of first, or higher, order.
Rates of Growth in a Class of Homogeneous Multidimensional Markov Chains
Authors: González M. , Martínez R. , Mota M.
Published: April 2006

We investigate the asymptotic behaviour of homogeneous multidimensional Markov chains whose states have nonnegative integer components. We obtain growth rates for these models in a situation similar to the near-critical case for branching processes, provided that they converge to infinity with positive probability. Finally, the general theoretical results are applied to a class of controlled multitype branching process in which random control is allowed.
First Passage Problems for Asymmetric Wiener Processes
Authors: Lefebvre Mario
Published: April 2006

The problem of computing the moment generating function of the first passage time T to a > 0 or −b < 0 for a one-dimensional Wiener process {X(t), t ≥ 0} is generalized by assuming that the infinitesimal parameters of the process may depend on the sign of X(t). The probability that the process is absorbed at a is also computed explicitly, as is the expected value of T.
A Lévy Process Reflected at a Poisson Age Process
Authors: Kella Offer , Boxma Onno , Mandjes Michel
Published: April 2006

We consider a Lévy process with no negative jumps, reflected at a stochastic boundary that is a positive constant multiple of an age process associated with a Poisson process. We show that the stability condition for this process is identical to the one for the case of reflection at the origin. In particular, there exists a unique stationary distribution that is independent of initial conditions. We identify the Laplace-Stieltjes transform of the stationary distribution and observe that it satisfies a decomposition property. In fact, it is a sum of two independent random variables, one of which has the stationary distribution of the process reflected at the origin, and the other the stationary distribution of a certain clearing process. The latter is itself distributed as an infinite sum of independent random variables. Finally, we discuss the tail behavior of the stationary distribution and in particular observe that the second distribution in the decomposition always has a light tail.
Exponential Behavior in the Presence of Dependence in Risk Theory
Authors: Albrecher Hansjörg , Teugels Jef L.
Published: April 2006

We consider an insurance portfolio situation in which there is possible dependence between the waiting time for a claim and its actual size. By employing the underlying random walk structure we obtain explicit exponential estimates for infinite- and finite-time ruin probabilities in the case of light-tailed claim sizes. The results are illustrated in several examples, worked out for specific dependence structures.
User-Optimal State-Dependent Routeing in Parallel Tandem Queues with Loss
Authors: Spicer Scott , Ziedins Ilze
Published: April 2006

We consider a system of parallel, finite tandem queues with loss. Each tandem queue consists of two single-server queues in series, with capacities C1 and C2 and exponential service times with rates μ1 and μ2 for the first and second queues, respectively. Customers that arrive at a queue that is full are lost. Customers arriving at the system can choose which tandem queue to enter. We show that, for customers choosing a queue to maximise the probability of their reaching the destination (or minimise their individual loss probability), it will sometimes be optimal to choose queues with more customers already present and/or with greater residual service requirements (where preceding customers are further from their final destination).
On the Waiting Time to Escape
Authors: Serra Maria Conceição
Published: April 2006

The mathematical model we consider here is a decomposable Galton-Watson process with individuals of two types, 0 and 1. Individuals of type 0 are supercritical and can only produce individuals of type 0, whereas individuals of type 1 are subcritical and can produce individuals of both types. The aim of this paper is to study the properties of the waiting time to escape, i.e. the time it takes to produce a type-0 individual that escapes extinction when the process starts with a type-1 individual. With a view towards applications, we provide examples of populations in biological and medical contexts that can be suitably modeled by such processes.
Poor People in Rich Nations: The United States in Comparative Perspective
Authors: Smeeding Timothy
Published: April 2006

Cross-national comparisons can teach lessons about antipoverty policy. While all nations value low poverty, high levels of economic self-reliance and equality of opportunity for younger persons, they differ dramatically in the extent to which they reach these goals. Nations also exhibit differences in the extent to which working age adults mix economic self-reliance (earned incomes), family support and government support to avoid poverty. We begin by reviewing international concepts and measures of poverty. The Luxembourg Income Study (LIS) database contains the information needed to construct comparable poverty measures for more than 30 nations. It allows comparisons of the level and trend of poverty and inequality across several nations, along with considerable detail on the sources of market incomes and public policies that shape these outcomes. We will highlight the different relationships between antipoverty policy and outcomes among several countries, and consider the implications of our analysis for research and for antipoverty policy in the United States. In doing so, we will draw on a growing body of evidence that evaluates antipoverty programs in a cross-national context.
Poverty in America: Trends and Explanations
Authors: Hoynes Hilary W , Page Marianne E , Stevens Ann Huff
Published: April 2006

Despite robust growth in real GDP per capita in the last three decades, U.S. poverty rates have changed very little. We summarize some basic facts about poverty in the United States, relying on a combination of previously published data from the Census Bureau and our own tabulations based on Current Population Survey data. We then discuss and evaluate four determinants of changes in the poverty rate that have been advanced in the literature: the impact of labor market opportunities; the role of changes in family structure; the role played by government antipoverty programs; and the role of immigration.
Addressing Absence
Authors: Banerjee Abhijit , Duflo Esther
Published: April 2006

Absent providers are a major problem both for public health facilities and primary schools in many developing countries. For example, in India, absence rates for teachers are over 24 percent, and for health providers they are over 40 percent. This paper presents evidence on a number of innovative strategies to reduce absenteeism in government– and nongovernmental organization–run schools and health facilities. These strategies were implemented in Kenya and India over the past few years and have been evaluated using the randomized evaluation methodology. The strategies involved alternative levers to fight absence. Some tried to improve incentives for providers, either through rewards and punishments implemented by external monitors, or through facilitating a more active involvement of those who expect to benefit from the service. Others are based on the idea that the providers are discouraged by the lack of interest among the potential beneficiaries in what they are being offered; these strategies aim at increasing the demand for the services as a way of putting more pressure on the providers. The results of these efforts, taken together, shed light not only on ways to address the problem of absence in the public sector, but also on the underlying reasons for this phenomenon.
Policy Watch: Debt Relief
Authors: Arslanalp Serkan , Henry Peter Blair
Published: April 2006

At the Gleneagles summit in July 2005, the heads of state from the G-8 countries—the United States, Canada, France, Germany, Italy, Japan, Russia and the United Kingdom—called on the International Monetary Fund (IMF), the World Bank and the African Development Bank to cancel 100 percent of their debt claims on the world's poorest countries. The world's richest countries have agreed in principle to forgive roughly $55 billion dollars owed by the world's poorest nations. This article considers the wisdom of the proposal for debt forgiveness, from the standpoint of stimulating economic growth in highly indebted countries. In the 1980s, debt relief under the “Brady Plan” helped to restore investment and growth in a number of middle-income developing countries. However, the debt relief plan for the Heavily Indebted Poor Countries (HIPC) launched by the World Bank and the International Monetary Fund in 1996 has had little impact on either investment or growth in the recipient countries. We will explore the key differences between the countries targeted by these two debt relief schemes and argue that the Gleneagles proposal for debt relief is, at best, likely to have little effect at all. Debt relief is unlikely to help the world's poorest countries because, unlike the middle-income Brady countries, their main economic difficulty is not debt overhang, but an absence of functional economic institutions that provide the foundation for profitable investment and growth. We will show that debt relief may be more valuable for Brady-like middle-income countries than for low-income ones because of how it leverages the private sector.
Optimal Sequential Exploration: A Binary Learning Model
Authors: Bickel J. Eric , Smith James E.
Published: April 2006

In this paper, we develop a practical and flexible framework for evaluating sequential exploration strategies in the case where the exploration prospects are dependent. Our interest in this problem was motivated by an oil exploration problem, and our approach begins with marginal assessments for each prospect (e.g., what is the probability that the well is wet?) and pairwise assessments of the dependence between prospects (e.g., what is the probability that both wells i and j are wet?). We then use information-theoretic methods to construct a full joint distribution for all outcomes from these marginal and pairwise assessments. This joint distribution is straightforward to calculate, has many nice properties, and appears to provide an accurate approximation for distributions likely to be encountered in practice. Given this joint probability distribution, we determine an optimal drilling strategy using an efficient dynamic programming model. We illustrate these techniques with an oil exploration example and study how dependence and risk aversion affect the optimal drilling strategies. The information-theory-based techniques for constructing joint distributions and dynamic programming model for determining optimal exploration strategies could be used together or separately in many other applications.
Multiobjective Value Analysis of Army Basic Training
Authors: Klimack William K. , Kloeber Jack M.
Published: April 2006

Basic combat training is the first course in initial entry training for U.S. Army enlisted soldiers. The training may be considered a portfolio of training tasks. A small number of tasks were suspected to be of lesser quality. Multiobjective decision analysis was employed to evaluate the tasks using stakeholder groups from various organizational levels. The results identified areas for improvement and also provided insight about how personnel at various levels of the training organization viewed the tasks and their training value differently. The decision maker adopted a number of recommendations and the valuation exercise provided a useful process for eliciting informal feedback from organization members. Several lessons learned from the study should be useful to others, including the benefit of examining stakeholders vertically in an organization and techniques that were helpful in gaining acceptance of decision analysis as the approach of choice.
Karmiloff‐Smith's RRM distinction between adjunctions and redescriptions: It's about time (and children's drawings)
Authors: Hollis Steve , Low Jason
Published: April 2006

A sample of 315 children aged between 6 and 9 years participated in a 5‐month longitudinal study aimed at investigating constraints on representational flexibility as observed in drawing behaviour. The study specifically looked at how external interventions affected children's representations over time. The intervention involved showing children various examples of pretend people in relation toKarmiloff‐Smith's (1990)task of requesting children to operate on their normal person drawing procedures. The study confirmed that knowledge introduced exogenously was only beneficial immediately after the intervention. Over time, in contrast to the older children, the younger children reverted to their internal representations that were specified as sequentially fixed lists. The intervention did not promote transfer of learning to the analogous task of drawing pretend houses. The study suggests that exogenous provocations of behaviour are driven by adjunctions, and that reiterated cycles of representational redescription must occur before the externally mediated knowledge becomes flexibly manipulable.
The development of enemy images in Dutch children: Measurement and initial findings
Authors: Oppenheimer Louis
Published: April 2006

While there is ample evidence that enemies and enemy images are prerequisites in preparedness for war, little information is available about children's understanding of enemies or the presence of enemy images. Based on a pilot study in which assessment instruments were developed and validated, the present study examined the understanding of enemies and the presence of enemy images in 221 Dutch children aged between 7 and 12 years. The instruments employed involved the request to draw an enemy and an individual interview. Contrary to the expectation that younger children's enemy images would consist primarily of fictitious, non‐human figures, whereas older children's images would focus more on realistic others as enemies, the findings revealed an opposite developmental course: younger children perceived enemies more often as concrete others, while older children perceived enemies more often as non‐human, fictitious others. In addition, an age‐related increase in children's experienced threats that cannot be reduced to concrete external causes was observed. Taken together with a growing awareness that enemies are characterized primarily by internal personality characteristics, latent (undefined) enemy images may easily become concrete enemies when an external focus is provided.
American Studies and Film, Blindness and Insight
Authors: Auerbach Jonathan
Published: April 2006

This essay examines the disciplinary relation between American studies and film studies following World War II, seeking to understand how and why American studies academics virtually ignored film as a fertile ground for cultural analysis until the 1970s. While intellectuals prior to WWII seemed open to the democratic and artistic potential of cinema, after the war some of these same critics began to disparage Hollywood movies in particular as symptoms of mass society. Although a few scholars in the US such as Adorno and Kracauer saw mass culture as itself worthy of analysis, virtually the entire first generation of American studies professors gave little scholarly consideration to popular cinema, even though some hinted at its crucial role as a collective, consensual dream or myth, and a few used movies for their teaching.

Looking closely at the earliest issues of the journal American Quarterly, I locate a brief moment at mid-century (1949-1952) when film was taken seriously, only to disappear from view and resurface after the advent of film studies programs in the late 1960s. I conclude with a reading of a striking pair of essays by Parker Tyler published in AQ in 1949 and 1950, one on the reality effects produced by narrative film's "eyewitness camera," and the other on contemporaneous Hollywood "problem pictures," especially those depicting race and racial passing. Now long forgotten, Tyler's sophisticated, devastating and daring ideological critique of these movies serves as an important precursor and model for American studies practice today. This lost intersection between film and American studies suggests in its unrealized promise how we would do well to pay careful attention to our discipline's past, its blind spots and insights, as we imagine our various futures.
"The Pill You Love Can Turn on You": Feminism, Tranquilizers, and the Valium Panic of the 1970s
Authors: Herzberg David L. (David Lowell)
Published: April 2006

This essay analyzes the cultural politics of a late-1970s Valium addiction scare in the context of other episodes of American drug hysteria. Since the days of "Demon Rum," antidrug campaigns in the U.S. typically associated drugs with marginal populations such as immigrants, nonwhites, or the urban poor. The "drug menace" helped dramatize the threat posed by such "dangerous classes" to "our" society, while mobilizing state police power to control it. The Valium panic was a different matter, involving a quintessentially middle-class drug prescribed legally by reputable physicians for their respectable patients, and popularly recognized as an entrenched part of life in the comfortable classes, especially for women. Its emergence signaled important but little-examined changes in American drug politics, and raised the prospect of a new kind of antidrug warrior.

Central to creating the Valium addiction scare were certain white, middle-class segments of the diverse "second-wave" feminist movement, who redeployed the powerful cultural tools of the drug war for their own agendas. They revised classic drug-scare narratives to sensationalize Valium addiction as a central symbol of sexism, and held up liberation from the "mother's little helper" as an archetypal story of self-emancipation through feminism. This was a remarkable campaign, earning new audiences for feminist political messages and challenging the punitive logic of the 20th century's "war against drugs." It was also, however, limited in important ways by the class and race dynamics of American drug politics. The stories about Valium addiction they constructed for popular consumption traded on assumptions of white, middle-class women's essential innocence in a way that excluded—and even reified—the "dangerous classes" as a different sort of drug user. And yet, their success in reworking the anti-drug tradition for their own ends challenges us to imagine exactly that: a "war against drugs" rebuilt as a civil rights campaign, challenging rather than reinforcing cultural stereotypes.
The Indian Passion Play: Contesting the Real Indian in Song of Hiawatha Pageants, 1901-1965
Authors: McNally Michael David
Published: April 2006

Each summer from 1901 to 1918, and intermittently thereafter through 1965, Odawa and Ojibwe actors in Northern Ontario and Michigan took part in operatic Native language performances of Longfellow's Song of Hiawatha financed by area railroads and captured on silent film. While audiences and reviewers understood the pageants to validate the reality of Longfellow's representations of vanished noble savages and while Native actors performed this script for pay in lean times, a closer look at their offstage lives, their onstage improvisations, and especially their humor reveals that these were also Indians playing Indian for Indian reasons. In an era of assimilation policies that outlawed drumming, dancing, and ceremony in public, and on stages designed to render them absent as twentieth century Native people, the actors insinuated their presence in heavily ramified, if subtle, ways. Crucially, performances enabled them to embody and thereby maintain a musical and dance repertoire associated with peoplehood and power, that could be rekindled with greater sovereignty by subsequent generations.