bluuebunny/crossref_metadata_2025_split huggingface dataset:
Smokeless tobacco‐induced lamellar body abnormalities
Authors: Colvard MD , Ashrafi SH , Alonge OK , Cordell GA 
Published: March 2006

Objectives:  To compare the morphological changes and quantitative distribution of lamellar bodies (Lb) (membrane coating granules) in the hamster cheek pouch epithelium with smokeless tobacco (ST).Materials and methods:  Archives of experimental material from previously published studies [S. Ashrafi, A. Das, R. Worawongvasu, B. Mehdinejad and J. Waterhouse (1992) Scanning Microscopy6: 183] were utilized. Animals in experimental group received most ST (snuff) in their right pouch, 5 days weekly, for 24 months, while no snuff was given to control group. After 24 months, the epithelial tissues were processed for electron microscopic study. Volume densities of Lb were assessed by morphometry.Main outcome measures:  Densities of Lb in the two groups, experimental vs control.Results:  In the control, Lb extruded their contents into the intercellular spaces of upper granular layers and in between the last granular cell layers and keratin layers to form a permeability barrier. Conversely, in the smokeless tobacco‐treated epithelium, the majority of the Lb that were formed remained inside and accumulated within the granular cells, without extruding their contents into the intercellular spaces to form a lipid compound permeability barrier.Conclusions:  Commercial alkaline ST may have contributed to the abnormal accumulation of Lb in the granular cell layer and affected the extrusion process of Lb to form an incomplete permeability barrier in the oral epithelium.
Roost Structure, Modification, and Availability in the White‐throated Round‐eared Bat,Lophostoma silvicolum(Phyllostomidae) Living in Active Termite Nests1
Authors: Kalko Elisabeth K. V. , Ueberschaer Katja , Dechmann Dina 
Published: March 2006

ABSTRACTWe studied roost structure, modification, and availability inLophostoma silvicolum(Phyllostomidae), an insectivorous gleaning bat, on Barro Colorado Island (BCI), Panamá. Collection of nest material beneath termitaria and infrared video filming indicated that males ofL. silvicolumexcavate and maintain cavities inside active termite nests. A binary logistic regression analysis showed that to be suitable as roosts, termite nests have to be larger than 30 cm in diameter and taller than 30 cm, well shaded, with few transecting branches, and freely accessible from below. Use of active termite nests as roosts may provide several benefits toL. silvicolum, including reduction of competition for roost sites with sympatric bat species, reduced parasite load and a suitable microclimate. A comparison of number of all termite nests in selected forest plots with number of termite nests that are potentially suited as bat roosts and number of termite nests that are actually used by bats suggests thatL. silvicolummay not be roost‐limited on BCI in spite of its highly specialized roost choice.
Ants on the Move: Resource Limitation of a Litter‐nesting Ant Community in Costa Rica1
Authors: McGlynn Terrence P. 
Published: March 2006

ABSTRACTThe leaf litter of tropical wet forests is replete with itinerant ant nests. Nest movement may help ants evade the constraints of stress and disturbance and increase access to resources. I studied how nest relocation and environmental factors may explain the density, size, and growth of leaf litter ant nests. I decoupled the relationships among litter depth, food abundance, and nest availability in a 4‐mo manipulation of food and leaf litter in a community of litter‐nesting ants in a lowland wet forest in Costa Rica. Over 4 mo, 290 1 m2treatment and control plots were sampled without replacement. Nest densities doubled in response to food supplementation, but did not decrease in response to litter removal or stress (from litter trampling). The supplementation of food increased the utilization of less favored nesting materials. In response to food supplementation and litter trampling, arboreal ants established nests in the litter, and growth rates of the most common ants (Pheidolespp.) increased. Colony growth was independent of colony size and growth rates of the most abundant ants. In general, I conclude that litter‐nesting ant density is driven primarily by food limitation, that nest relocation behavior significantly affects access to resource and the demographic structure of this community, and that nest fission may be a method to break the growth–reproduction trade‐off.
Recovery of a Subtropical Dry Forest After Abandonment of Different Land Uses1
Authors: Colón Sandra Molina , Lugo Ariel E. 
Published: March 2006

ABSTRACTWe studied the ecological characteristics of 45–50‐yr‐old subtropical dry forest stands in Puerto Rico that were growing on sites that had been deforested and used intensively for up to 128 yr. The study took place in the Guánica Commonwealth Forest. Our objective was to assess the long‐term effects of previous land use on this forest—i.e., its species composition, structure, and functioning. Previous land‐use types included houses, farmlands, and charcoal pits. Stands with these land uses were compared with a nearby mature forest stand. The speed and path of forest recovery after deforestation and land‐use abandonment depended on the conditions of the land. Study areas where land uses had removed the forest canopy and altered soil conditions (houses and farmlands) required a longer time to recover and had a different species composition than study areas where land uses retained a forest canopy (charcoal pits). Different forest attributes recovered at different rates. Crown area index, stem density, and litterfall rate recovered faster than stemwood and root, biomass, tree height, and basal area. Where previous land uses removed the canopy,Leucaena leucocephala,a naturalized alien pioneer species, dominated the regrowth. Native species dominated abandoned charcoal pits and mature forest. The change in species composition, including the invasion of alien species, appears to be the most significant long‐term effect of human use and modification of the landscape.
On the origin of the iron Kα line cores in active galactic nuclei
Authors: Nandra K. 
Published: March 2006

Abstract
X-ray observations made with Chandra and XMM–Newton have shown that there are relatively narrow cores to the iron Kα emission lines in active galactic nuclei (AGN). Plausible origins for this core emission include the outer regions of an accretion disc, a parsec-scale molecular torus, and the optical broad-line region (BLR). Using data from the literature it is shown that no correlation exists between the Fe Kα core width and the BLR (specifically Hβ) line width. This shows that in general the iron Kα core emission does not arise from the BLR. There is a similar lack of correlation between the width of the Fe Kα core and black hole mass. The average Kα width is about a factor of 2 lower than the Hβ width. It therefore seems likely that, in many cases, the narrow core arises in the torus. There is a very wide range of observed Fe Kα core widths, however, and this argues for multiple origins. The simplest explanation for the observed line profiles in AGN is that they are due to a mixing of very narrow emission from the inner edge of the torus, and broadened emission from the accretion disc, in varying proportions from object to object.
Spiral structure of the third galactic quadrant and the solution to the Canis Major debate
Authors: Moitinho A. , Vázquez R. A. , Carraro G. , Baume G. , Giorgi E. E. , Lyra W. 
Published: March 2006

Abstract
With the discovery of the Sagittarius dwarf spheroidal, a galaxy caught in the process of merging with the Milky Way, the hunt for other such accretion events has become a very active field of astrophysical research. The identification of a stellar ring-like structure in Monoceros, spanning more than 100°, and the detection of an overdensity of stars in the direction of the constellation of Canis Major (CMa), apparently associated to the ring, has led to the widespread belief that a second galaxy being cannibalized by the Milky Way had been found. In this scenario, the overdensity would be the remaining core of the disrupted galaxy and the ring would be the tidal debris left behind. However, unlike the Sagittarius dwarf, which is well below the Galactic plane and whose orbit, and thus tidal tail, is nearly perpendicular to the plane of the Milky Way, the putative CMa galaxy and ring are nearly co-planar with the Galactic disc. This severely complicates the interpretation of observations. In this Letter, we show that our new description of the Milky Way leads to a completely different picture. We argue that the Norma–Cygnus spiral arm defines a distant stellar ring crossing Monoceros and the overdensity is simply a projection effect of looking along the nearby local arm. Our perspective sheds new light on a very poorly known region, the third Galactic quadrant, where CMa is located.
The Tax Consequences of Long‐Run Pension Policy*
Authors: Black Fischer 
Published: March 2006

A firm's pension fund is legally separate from the firm. But because pension benefits are normally independent of fund performance, pension assets impact the firm very much as if they were firm assets.Because they are worth more when times are good and less when times are bad, common stocks in the pension fund add to the sponsoring firm's leverage. They cause contributions to a pension fund to be high just when the firm can least afford to pay them. Conversely, bonds in the pension fund will make it easier for the firm to avoid default on its own bonds when times are bad all over: The more bonds a pension fund buys, the more the firm can borrow.The tax treatment accorded the pension fund differs notably from that accorded the firm. Some have argued that a firm can capitalize on the difference by accelerating the funding of its pension plan. The benefits of full funding are wasted, however, unless the added contributions to the fund are invested in bonds; higher pension contributions now mean lower contributions later, hence higher taxes later. The benefits come from earning, after taxes, the pretax interest rate on the bonds in the pension fund.If the firm wants to take advantage of the differing tax treatment of bonds without altering the level of its current pension contributions, it can (1) sell stocks in the pension fund and then buy bonds with the proceeds while (2) issuing debt in the firm and buying back its own shares with the proceeds. An investment in the firm's own stock creates no more tax liability than an investment in stocks through the pension fund.
Allocating Shareholder Capital to Pension Plans
Authors: Merton Robert C. 
Published: March 2006

This article discusses the corporate challenge of providing retirement income to employees while limiting the costs and risks of pension plans to the companies themselves by addressing five main questions:

What are the major issues and challenges surrounding pensions? Although the pension shortfalls have been the focus of attention, the author argues that the more serious concern is the risk stemming from the mismatch between pension assets and pension liabilities— that is, the funding of debt‐like liabilities with equity‐heavy asset portfolios.
To what extent do the equity market and equity prices reflect the shortfall in value and the mismatch in risk? While the author describes some evidence of the market's ability to capture pension risk, analysts' P/E multiples and management's assessments of cost of capital may still be distorted by failure to take full account of the risks associated with pension assets.
How should management analyze and formulate strategic solutions? Without offering specific solutions, the author presents a framework for analyzing the problem from a strategic perspective that can be used in formulating a company's pension policy. In particular, the article recommends that companies take an integrated perspective that views pension assets and liabilities as parts of the corporate balance sheet, and the pension asset allocation decision as a critical aspect of a corporate‐wide enterprise risk management program.
If a company chooses to make a major change in its pension policy, such as a partial or complete immunization accomplished by substituting bonds for stocks, how would you communicate the new policy to the rating agencies and investors?
What are the major issues to be thinking about when contemplating a change from a DB plan to a defined contribution, or DC, plan? The author argues that DC plans without some corporate oversight or responsibility for results are not a long‐term solution.
An Investment Management Methodology for Publicly Held Property/Casualty Insurers
Authors: Heyman William H. , Rowland David D. 
Published: March 2006

Investment officers of publicly held property/casualty companies wrestle with the question of how best to contribute to shareholder value. Should they view themselves as managers of a closed‐end investment company that happens to be funded by insurance underwriting? Or should they instead be investing funds primarily to defease the firm's liabilities and thus support the operations of a company whose principal value derives from its insurance activities?The authors of this article suggest that the investment policy of most insurance companies should have two primary objectives: (1) immunizing insurance reserves with a fixed‐income portfolio and (2) earning “abnormal returns” on surplus in “a responsible and disciplined” way. The latter means adhering to an asset allocation approach that takes account of the risk‐reward tradeoffs presented by a broad variety of investment types as well as the accounting treatment of investment income. Both accounting and economic considerations lead the authors to suggest that after‐tax net investment income (“NII”), as defined by U.S. GAAP, is the best benchmark of performance. While focusing mainly on the fixed income part of the portfolio, the authors suggest active management and portfolio approaches that aim to produce a growing, but relatively stable NII. Consistent with GAAP's treatment of NII (which includes interest income but excludes most capital gains) as “recurring income,” the authors argue that the market appears to assign significantly higher multiples to NII than to other sources of reported income.
How Behavioral Finance Can Inform Retirement Plan Design1
Authors: Mitchell Olivia S. , Utkus Stephen P. 
Published: March 2006

Several key lessons for pension design have emerged in the last decade from behavioral economics and finance research. This article analyzes the insights from this literature on how workers decide to save, manage their retirement investments, and draw down their assets in retirement. The aim is to understand how workers and retirees deviate from the rational, well‐informed agents that underpin economic theory, public policy, and often retirement plan design.The evidence suggests that many people save too little, others make poor investment decisions, and still others spend their accumulated assets too quickly in retirement. The “behavioral” reasons for such tendencies include overconfidence, limited self‐control, the overvaluation of the present at the expense of the future, susceptibility to “framing,” and an aversion to realizing losses.By shedding light on why people fail to achieve an ideal outcome on their own, this literature offers practical guidance to plan sponsors and policymakers who must design, regulate, and evaluate the institutions that help provide for economic security in old age. More specifically, the literature suggests that the plan design should be made automatic for the many individuals unwilling to exercise full control over their retirement savings choices. Recommended design features include automatic enrollment, scheduled annual savings increases, and default investment options or managed account programs that represent optimal portfolio choices.
Downside Risk in Practice
Authors: Estrada Javier 
Published: March 2006

Although investors associate risk with negative outcomes and downside fluctuations, modern portfolio theory does not. For investors, volatility per se is not necessarily bad; volatility below a benchmark is. A stock that magnifies the market's fluctuations is not necessarily bad; one that magnifies the market's downside swings is. Even Harry Mar‐kowitz, the father of modern portfolio theory, viewed downside risk as a better way to assess risk than the “mean‐variance” framework that he ultimately proposed and that has since become the standard.This article highlights the shortcomings of traditional measures of risk (the standard deviation and beta), introduces the concept of downside risk, and discusses two measures of it—the “semideviation” and “downside beta.” It also discusses the use of such measures in asset pricing models to estimate required returns on equity. Data from a few well‐known companies are used to illustrate that the cost of equity based on downside risk can be substantially different from that based on the CAPM. The article concludes with a brief discussion of risk‐adjusted returns and a comparison of the traditional method of calculating such returns with both the Sharpe ratio and its counterpart in a downside risk framework, the Sortino ratio. The appendix demonstrates how to calculate these risk measures in Excel.
The influences of postdischarge management by nurse practitioners on hospital readmission for heart failure
Authors: Delgado‐Passler Patricia , McCaffrey Ruth 
Published: March 2006

AbstractPurpose: The primary purpose of this literature review is to examine advanced practice nurse (APN)–directed versus registered nurse (RN)–directed telemanagement programs for heart failure patients.Data sources: Research articles identified through CINAHL and OVID databases.Conclusions: Implementing a telemanagement program directed by an APN after hospital discharge decreases the costs and frequent rehospitalizations associated with heart failure and improves the patient's quality of life. While APNs are more costly than RNs, it is important to understand that this level of provider has a more significant impact on the outcomes of patients who use the services provided in the comprehensive discharge programs.Implications for practice: An APN‐directed heart failure telemanagement program can reduce the rising healthcare costs that result from frequent readmissions. These programs can improve the quality of care given to heart failure patients while reducing the cost to the institution, the patient, and the healthcare system. When considering the number of older adults hospitalized each year with heart failure, the potential patient benefits and savings to the healthcare system resulting from APN‐directed telemanagement are substantial.
Emergency contraception: Knowledge and perceptions in a university population
Authors: Corbett Patricia O. , Mitchell Cameron P. , Taylor Julie Smith , Kemppainen Jeanne 
Published: March 2006

AbstractPurpose: The purpose of this study was to examine knowledge, attitudes, and behaviors regarding emergency contraception (EC) in university men and women aged 18–21.Data sources: Data sources included responses to a 25‐item questionnaire and an 8‐item demographic survey completed anonymously at a public site on campus. Ninety‐seven university students participated in the study. Participants were asked to respond to questions relating to knowledge, attitudes, and behaviors regarding EC, perceived worthiness, objections, sources of information about EC, preferred birth‐control method and usage, and perceptions of their personal risk of unintended pregnancy.Conclusions: Many respondents considered unintended pregnancy to be a major problem and considered EC a worthy option in the event of method failure or unprotected intercourse. While most participants were aware that there was a postcoital method of contraception, confusion existed between EC and RU‐486 (the abortion pill). Almost half (49.5%) believed that EC was the same as RU‐486. There was an association between advanced prescription for EC and its likelihood of use. Most women would be significantly more likely to use EC if they had a prescription on hand. Of the women who were less likely to choose EC, 100% indicated they would feel embarrassed or judged when asking for it. Only 34% of those women who have had a gynecological exam in the past 12 months had discussed EC with their provider.Implications for practice: Advanced practice nurses need to incorporate EC into preventive health counseling for both men and women. Providing women with an advanced prescription increases the likelihood that women will use EC.
Therapeutic modulation of the psychoneuroimmune system by medical acupuncture creates enhanced feelings of well‐being
Authors: Walling Allan 
Published: March 2006

AbstractPurpose: This article includes an explanation of how stressors disrupt physiologic regulatory mechanisms leading to disease states, how environmental challenges alter the function of the psychoneuroimmune system, and how correction of aberrant action potentials will stabilize homeostatic regulatory functions, inducing an escape response from stressors and leading to enhanced feelings of well‐being. An explanation of how medical acupuncture accomplishes this stabilization concludes the article.Data source: Extensive review of the worldwide scientific literature from the 1970s through current literature, on acupuncture, neurophysiology, and psychoneuroimmune system, using the theoretical framework of Martha Rogers.Conclusions:It is estimated that 80% of all illnesses are stress induced, although the physiologic mechanisms by which stress induces detrimental changes are not well understood by the medical profession. Introducing specific rhythmic electrical impulses slightly more intense than the nervous system already generates with the intervention of medical acupuncture can therapeutically alter aberrant signals induced by stressors, which may result in the release of neuropeptides and stabilization of homeostatic regulation so that health outcomes are improved. As neurological activity is altered, the firing pattern of nerves is changed. This is a change in the electrical pattern that leads to a change in the biochemical pattern. Thus, medical acupuncture is a therapy that is in agreement with Martha Rogers’ conceptual model. Therapeutic techniques may improve the individual's level of wellness by direct actions toward homeostatic stabilization of the autonomic nervous system. These techniques will not change the amount of stressors a person is subject to but will change the physiological response to them. When the nervous system is in homeostatic balance, individuals will report enhanced feelings of well‐being, be more effective in coping with their conditions of living, and therefore be less susceptible to illness.Implications for practice:Nurse practitioners have an opportunity to expand into an unused dimension for nursing care through direct treatment of the central and autonomic nervous system that will influence the psychoneuroimmune system. A prescriptive theory explaining medical acupuncture provides for therapeutic interventions at the primary, secondary, and tertiary level of care. Primary preventive interventions alter the effects of stress before it leads to illness by assisting homeostatic stability of the autonomic nervous system. Secondary interventions allow treatment of many health conditions regulated by neurological activity. Tertiary care provides a method to assist autonomic regulation when the body is no longer able to maintain homeostatic stability because of chronic illness or injury.