bluuebunny/crossref_metadata_2025_split huggingface dataset:
Robust Designs for Linear Mixed Effects Models
Authors: Berger Martijn P. F. , Tan Frans E. S. 
Published: September 2004

SummaryIn health sciences, medicine and social sciences linear mixed effects models are often used to analyse time-structured data. The search for optimal designs for these models is often hampered by two problems. The first problem is that these designs are only locally optimal. The second problem is that an optimal design for one model may not be optimal for other models. In this paper the maximin principle is adopted to handle both problems, simultaneously. The maximin criterion is formulated by means of a relative efficiency measure, which gives an indication of how much efficiency is lost when the uncertainty about the models over a prior domain of parameters is taken into account. The procedure is illustrated by means of three growth studies. Results are presented for a vocabulary growth study from education, a bone gain study from medical research and an epidemiological decline in height study. It is shown that, for the mixed effects polynomial models that are applied to these studies, the maximin designs remain highly efficient for different sets of models and combinations of parameter values.
Hedge Funds and the Technology Bubble
Authors: K. BRUNNERMEIER MARKUS , NAGEL STEFAN 
Published: September 2004

ABSTRACTThis paper documents that hedge funds did not exert a correcting force on stock prices during the technology bubble. Instead, they were heavily invested in technology stocks. This does not seem to be the result of unawareness of the bubble: Hedge funds captured the upturn, but, by reducing their positions in stocks that were about to decline, avoided much of the downturn. Our findings question the efficient markets notion that rational speculators always stabilize prices. They are consistent with models in which rational investors may prefer to ride bubbles because of predictable investor sentiment and limits to arbitrage.
Cash and Corporate Control
Authors: FALEYE OLUBUNMI 
Published: September 2004

ABSTRACTThe takeover market is often suggested as appropriate for containing the agency problems of excessive corporate cash holdings. However, recent studies report contradictory evidence. I focus on the takeover‐deterrence effects of corporate liquidity and suggest the proxy contest as an effective alternative control mechanism. I find that proxy fight targets hold 23% more cash than comparable firms, and that the probability of a contest is significantly increasing in excess cash holdings. Proxy fight announcement return also is positively related to excess cash. Following a contest, executive turnover and special cash distributions to shareholders increase, while cash holdings significantly decline.
Dividend Changes and the Persistence of Past Earnings Changes
Authors: KOCH ADAM S. , SUN AMY X. 
Published: September 2004

ABSTRACTWe examine whether the market interprets changes in dividends as a signal about the persistence of past earnings changes. Prior to observing this signal, investors may believe that past earnings changes are not necessarily indicative of future earnings levels. We empirically investigate whether a change in dividends alters investors' assessments about the valuation implications of past earnings. Results confirm the hypothesis that changes in dividends cause investors to revise their expectations about the persistence of past earnings changes. This effect varies predictably with the magnitude of the dividend change and the sign of the past earnings change.
Idiosyncratic Consumption Risk and the Cross Section of Asset Returns
Authors: JACOBS KRIS , WANG KEVIN Q. 
Published: September 2004

ABSTRACTThis paper investigates the importance of idiosyncratic consumption risk for the cross‐sectional variation in asset returns. We find that besides the rate of aggregate consumption growth, the cross‐sectional variance of consumption growth is also a priced factor. This suggests that consumers are not fully insured against idiosyncratic consumption risk, and that asset returns reflect their attempts to reduce their exposure to this risk. The resulting two‐factor consumption‐based asset pricing model significantly outperforms the CAPM, and its performance compares favorably with that of the Fama–French three‐factor model.
Remuneration, Retention, and Reputation Incentives for Outside Directors
Authors: YERMACK DAVID 
Published: September 2004

ABSTRACTI study incentives received by outside directors in Fortune 500 firms from compensation, replacement, and the opportunity to obtain other directorships. Previous research has only shown these relations to apply under limited circumstances such as financial distress. Together these incentive mechanisms provide directors with wealth increases of approximately 11 cents per $1,000 rise in firm value. Although smaller than the performance sensitivities of CEOs, outside directors' incentives imply a change in wealth of about $285,000 for a 1 standard deviation (SD) change in typical firm performance. Cross‐sectional patterns of director equity awards conform to agency and financial theories.
Bids and Allocations in European IPO Bookbuilding
Authors: JENKINSON TIM , JONES HOWARD 
Published: September 2004

ABSTRACTThis paper uses evidence from a data set of 27 European IPOs to analyze how investors bid and the factors that influence their allocations. We also make use of a unique ranking of investor quality, associated with the likelihood of flipping the IPO. We find that investors perceived to be long‐term holders of the stock are consistently favored in allocation and in out‐turn profits. In contrast to Cornelli and Goldreich (2001), we find little evidence that more informative bids receive larger allocations or higher profits. Our results cast doubt upon the extent of information production during the bookbuilding period.
The Development of Secondary Market Liquidity for NYSE‐Listed IPOs
Authors: CORWIN SHANE A. , HARRIS JEFFREY H. , LIPSON MARC L. 
Published: September 2004

ABSTRACTFor NYSE‐listed IPOs, limit order submissions and depth relative to volume are unusually low on the first trading day. Initial buy‐side liquidity is higher for IPOs with high‐quality underwriters, large syndicates, low insider sales, and high premarket demand, while sell‐side liquidity is higher for IPOs that represent a large fraction of outstanding shares and have low premarket demand. Our results suggest that uncertainty and offer design affect initial liquidity, though order flow stabilizes quickly. We also find that submission strategies are influenced by expected underwriter stabilization and preopening order flow contains information about both initial prices and subsequent returns.
Quality of Life in Women With Breast Cancer in Turkey
Authors: Uzun Özge , Aslan Fatma Eti , Selimen Deniz , Koç Mehmet 
Published: September 2004

Purpose

: To determine quality of life (QoL) of Turkish women with breast cancer, and to examine whether QoL was related to sociodemographic or clinical variables.
Design

: This descriptive study was conducted with a convenience sample of 72 Turkish women with breast cancer recruited from two hospitals in Turkey.
Methods

: The data were collected using a questionnaire, the Quality of Life Scale (QoLS), and the Visual Analogue Scale (VAS), and were analyzed using descriptive statistics.
Findings

: Two sociodemographic variables (educational background and employment status) were related to QoL of women with breast cancer. No statistically significant difference was found between patients with and without pain on scores obtained from the overall QoLS.
Conclusions

: The mean scores of total scale and subscales related to QoL perceived by women were considered to be moderately high. However, findings showed that educational level, employment status, and level of pain affected the level of QoL in Turkish women with breast cancer in varying degrees. Further studies are needed to determine specific effects of sociodemographic and clinical variables on QoL.
Role Strain and Ease in Decision‐Making to Withdraw or Withhold Life Support for Elderly Relatives
Authors: Hansen Lissi , Archbold Patricia G. , Stewart Barbara J. 
Published: September 2004

Purpose

: To describe the concepts of role strain and role satisfaction (renamed ease in decision‐making following analysis) experienced by family caregivers when making decisions to withdraw or withhold life support for elderly relatives in a variety of settings.
Methods

: Semi‐structured interviews were conducted with 17 family caregivers to obtain descriptions of their experiences when making decisions about life support for elderly relatives. Content analysis was used to analyze the data.
Findings

: Role strain was complex, dynamic, and multidimensional, and it evolved over time before, during, and after decision making about life support. Role satisfaction, the concept name used at the beginning of the study, did not match descriptions or the experience of family caregivers, and a revised name, ease in decision‐making, was selected.
Conclusions

: The concepts of role strain and ease in decision‐making have not previously been used in studies of decisions about life support. Both role strain and ease in decision‐making augment the existing literature on role strain in family care by providing a more complete picture of caregivers' responses during their experience of making life‐support decisions. Research focused on the measurement of strain and ease in decision‐making is needed to understand their interrelationship as well as their association with such variables as caregiver grief and health.
Cross‐Cultural Relationships Between Nurses and Filipino Canadian Patients
Authors: Pasco Alberta Catherine Y. , Morse Janice M. , Olson Joanne K. 
Published: September 2004

Purpose

: To describe culturally embedded values that implicitly guide Filipino Canadian patients' interactions with Canadian nurses and are integral to nurse‐patient relationships.
Design

and

Methods

: A focused ethnography was conducted, with a purposive sample of 23 Filipino Canadians who received care in Canadian hospitals. Data consisted of interviews, field notes, and diary.
Findings

: When receiving care, patients delineated hindi ibang tao (one of us) and ibang tao (not one of us) and this determined their preference for who performed personal and private tasks or received information. The urgency of the patients' conditions, the intimacy required for most nursing procedures, and short hospitalizations meant that patients often interacted without progressing through the cultural levels of pakikitungo (formality), pakikibagay (adjustability), and pakikisama (acceptance). Rather, the crisis of being hospitalized forced patients to immediately move toward the cultural levels of pakikipagpalagayang‐loob (mutual comfort) or pakikiisa (oneness). Patients' willingness to trust and to share their kapwa‐oriented worldview in relating with fellow human beings, and their use of their languages of words, gaze, touch, and food, allowed nurses to become hindi ibang tao (one of us). Caregiving roles and establishing relationships also distinguished that hindi ibang tao (one of us) was to bantay (watch over) the patient, whereas ibang tao (not one of us) was expected to alaga (care for) them (i.e., provide professional care).
Conclusions

: Communicating and caring effectively requires understanding of Filipino Canadians' languages of words, gaze, touch, and food and their levels of interaction. Culturally safe nurse‐patient relationships can then develop.
A Comparison of Three Measures of Elder Abuse
Authors: Meeks‐Sjostrom Diana 
Published: September 2004

Purpose

: To present a comparison of three measures for assessing elder abuse.
Design and Methods

: Three measures for assessing elder abuse were identified through a literature review. The characteristics and uses of each measure were reviewed and evaluated.
Findings

: The Indicators of Abuse (IOA) is a 22‐item tool for discriminating abuse and nonabuse cases; it is completed by a health care professional after a home assessment is conducted. The Elder Abuse and Neglect Assessment (EAI) is a 44‐item scale comprised of seven sections to review signs, symptoms, and subjective complaints of elder abuse, neglect, exploitation, and abandonment; it can be used by health care providers in all clinical settings. The Elder Abuse Screening Test (EAST) is a 15‐item tool to be completed by a health care provider based on the patient's responses. This screening tool is limited because of the small unrepresentative samples used to test it, the low internal consistency, and a relatively high false‐negative rate.
Conclusions

: An instrument to accurately assess elder abuse in long‐term care is needed. Proper identification of elder abuse is the first step in assisting victims in dealing with abusive situations.
MR Perfusion Imaging for the Detection of Myocardial Ischemia
Authors: Janssen C. H. C. , Kuijpers D. , Oudkerk M. 
Published: September 2004

AbstractA wide variety of imaging modalities is available for the diagnosis of ischemic coronary artery disease (CAD). Myocardial hypo‐perfusion is one of the first steps in the ischemic cascade and can be detected before clinical symptoms, ECG alterations or wall motion abnormalities occur. Currently, nuclear medicine techniques (scintigraphy) such as single‐photon emission computed tomography using Thalium‐201 or TC‐99 m sestamibi are most frequently used for the imaging of myocardial perfusion. Positron emission tomography (PET) is the reference standard for myocardial perfusion imaging. These techniques attain a sensitivity and specificity for the detection of myocardial ischemia of, respectively, 83–95 and 53–95%. However, PET is not widely available, which makes it relatively inaccessible. Other disadvantages of myocardial perfusion imaging scintigraphy are: high costs, long‐time commitment, radiation exposure, specificity depending on quality control of laboratory and trained readers and low specificity in presence of left bundle branch block. As a result of the fast hardware and software development magnetic resonance imaging (MRI) has become a promising new technique for perfusion imaging. This paper will give an introduction to myocardial perfusion MRI for the detection of ischemic heart disease followed by an overview of the post‐processing procedures.
System for Segmentation and Selective Visualization of the Coronary Artery Tree for Evaluation of Stenosis, Soft Plaque and Calcification in Cardiac CTA
Authors: Krishnamoorthy P. , Brejl M. , van Ooijen P. M. A. 
Published: September 2004

AbstractRecent advances in multidetector computed tomography (MDCT) technology provide opportunities for non‐invasive high‐resolution diagnostic imaging of the coronary arteries. The amount of image data generated in a coronary computed tomography angiography (CTA) study typically requires that the analysis be done using a 3D workstation. Manual interpretation of the data is normally feasible; however, semi‐automated and automated tools for coronary artery analysis can significantly shorten the analysis time. In this article, we discuss the coronary artery analysis package available on the Vitrea 2 (Vital Images, Inc.) workstation. The software is intended to expedite the review workflow by providing semi‐automated interactive tools for tracking vessels, automated curved and oblique reformations, and advanced 3D visualization. Early results from clinical evaluation indicate that using the automated tools can decrease the reading time by approximately a factor of 2.
Characterization and Heterologous Expression of the Oxalyl Coenzyme A Decarboxylase Gene from
Bifidobacterium lactis
Authors: Federici Federica , Vitali Beatrice , Gotti Roberto , Pasca Maria Rosalia , Gobbi Silvia , Peck Ammon B. , Brigidi Patrizia 
Published: September 2004

ABSTRACT

Oxalyl coenzyme A (CoA) decarboxylase (Oxc) is a key enzyme in the catabolism of the highly toxic compound oxalate, catalyzing the decarboxylation of oxalyl-CoA to formyl-CoA. The gene encoding a novel oxalyl-CoA decarboxylase from
Bifidobacterium lactis
DSM 10140 (
oxc
) was identified and characterized. This strain, isolated from yogurt, showed the highest oxalate-degrading activity in a preliminary screening with 12 strains belonging to
Bifidobacterium
, an anaerobic intestinal bacterial group largely used in probiotic products. The
oxc
gene was isolated by probing a
B. lactis
genomic library with a probe obtained by amplification of the oxalyl-CoA decarboxylase gene from
Oxalobacter formigenes
, an anaerobic bacterium of the human intestinal microflora. The
oxc
DNA sequence analysis revealed an open reading frame of 1,773 bp encoding a deduced 590-amino-acid protein with a molecular mass of about 63 kDa. Analysis of amino acid sequence showed a significant homology (47%) with oxalyl-CoA decarboxylase of
O. formigenes
and a typical thiamine pyrophosphate-binding site that has been reported for several decarboxylase enzymes. Primer extension experiments with
oxc
performed by using RNA isolated from
B. lactis
identified the transcriptional start site 28 bp upstream of the ATG start codon, immediately adjacent to a presumed promoter region. The protein overexpressed in
Escherichia coli
cross-reacted with an anti-
O. formigenes
oxalyl-CoA decarboxylase antibody. Enzymatic activity, when evaluated by capillary electrophoresis analysis, demonstrated that the consumption substrate oxalyl-CoA was regulated by a product inhibition of the enzyme. These findings suggest a potential role for
Bifidobacterium
in the intestinal degradation of oxalate.
Display of Bacterial Lipase on the
Escherichia coli
Cell Surface by Using FadL as an Anchoring Motif and Use of the Enzyme in Enantioselective Biocatalysis
Authors: Lee Seung Hwan , Choi Jong-Il , Park Si Jae , Lee Sang Yup , Park Byoung Chul 
Published: September 2004

ABSTRACT

We have developed a novel cell surface display system by employing FadL as an anchoring motif, which is an outer membrane protein involved in long-chain fatty acid transport in
Escherichia coli
. A thermostable
Bacillus
sp. strain TG43 lipase (44.5 kDa) could be successfully displayed on the cell surface of
E. coli
in an active form by C-terminal deletion-fusion of lipase at the ninth external loop of FadL. The localization of the truncated FadL-lipase fusion protein on the cell surface was confirmed by confocal microscopy and Western blot analysis. Lipase activity was mainly detected with whole cells, but not with the culture supernatant, suggesting that cell lysis was not a problem. The activity of cell surface-displayed lipase was examined at different temperatures and pHs and was found to be the highest at 50°C and pH 9 to 10. Cell surface-displayed lipase was quite stable, even at 60 and 70°C, and retained over 90% of the full activity after incubation at 50°C for a week. As a potential application, cell surface-displayed lipase was used as a whole-cell catalyst for kinetic resolution of racemic methyl mandelate. In 36 h of reaction, (
S
)-mandelic acid could be produced with the enantiomeric excess of 99% and the enantiomeric ratio of 292, which are remarkably higher than values obtained with crude lipase or cross-linked lipase crystal. These results suggest that FadL may be a useful anchoring motif for displaying enzymes on the cell surface of
E. coli
for whole-cell biocatalysis.
Effect of Length of Time before Incorporation on Survival of Pathogenic Bacteria Present in Livestock Wastes Applied to Agricultural Soil
Authors: Hutchison M. L. , Walters L. D. , Moore A. , Crookes K. M. , Avery S. M. 
Published: September 2004

ABSTRACTIn response to reports that the contamination of food can occur during the on-farm primary phase of food production, we report data that describes a possible cost-effective intervention measure. The effect of time before soil incorporation of livestock wastes spread to land on the rate of decline of zoonotic agents present in the waste was investigated. Fresh livestock wastes were inoculated with laboratory-culturedSalmonella,Listeria, andCampylobacterspp. andEscherichia coliO157 before they were spead onto soil. Incorporation of the spread wastes was either immediate, delayed for 1 week, or did not occur at all. Bacterial decline was monitored over time and found to be significantly more rapid for all waste types when they were left on the soil surface. There were no significant differences in initial bacterial decline rates when wastes were spread in summer or winter. Our results indicate that not incorporating contaminated livestock wastes into soil is a potential intervention measure that may help to limit the spread of zoonotic agents further up the food chain. The implications of these findings are discussed in relation to current advice for livestock waste disposal.
Copper Ions Stimulate Polyphosphate Degradation and Phosphate Efflux in
Acidithiobacillus ferrooxidans
Authors: Alvarez Sergio , Jerez Carlos A. 
Published: September 2004

ABSTRACT

For some bacteria and algae, it has been proposed that inorganic polyphosphates and transport of metal-phosphate complexes could participate in heavy metal tolerance. To test for this possibility in
Acidithiobacillus ferrooxidans
, a microorganism with a high level of resistance to heavy metals, the polyphosphate levels were determined when the bacterium was grown in or shifted to the presence of a high copper concentration (100 mM). Under these conditions, cells showed a rapid decrease in polyphosphate levels with a concomitant increase in exopolyphosphatase activity and a stimulation of phosphate efflux. Copper in the range of 1 to 2 μM greatly stimulated exopolyphosphatase activity in cell extracts from
A. ferrooxidans
. The same was seen to a lesser extent with cadmium and zinc. Bioinformatic analysis of the available
A. ferrooxidans
ATCC 23270 genomic sequence did not show a putative
pit
gene for phosphate efflux but rather an open reading frame similar in primary and secondary structure to that of the
Saccharomyces cerevisiae
phosphate transporter that is functional at acidic pH (Pho84). Our results support a model for metal detoxification in which heavy metals stimulate polyphosphate hydrolysis and the metal-phosphate complexes formed are transported out of the cell as part of a possibly functional heavy metal tolerance mechanism in
A. ferrooxidans
.