bluuebunny/crossref_metadata_2025 huggingface dataset:
A model of impairment and functional limitation in rheumatoid arthritis
Authors: Escalante Agustín , Haas Roy W , del Rincón Inmaculada
Published: March 2005

Background

We have previously proposed a theoretical model for studying physical disability and other outcomes in rheumatoid arthritis (RA). The purpose of this paper is to test a model of impairment and functional limitation in (RA), using empirical data from a sample of RA patients. We based the model on the disablement process framework.

Methods

We posited two distinct types of impairment in RA: 1) Joint inflammation, measured by the tender, painful and swollen joint counts; and 2) Joint deformity, measured by the deformed joint count. We hypothesized direct paths from the two impairments to functional limitation, measured by the shirt-button speed, grip strength and walking velocity. We used structural equation modeling to test the hypothetical relationships, using empirical data from a sample of RA patients recruited from six rheumatology clinics.

Results

The RA sample was comprised of 779 RA patients. In the structural equation model, the joint inflammation impairment displayed a strong significant path toward the measured variables of joint pain, tenderness and swelling (standardized regression coefficients 0.758, 0.872 and 0.512, P ≤ 0.001 for each). The joint deformity impairment likewise displayed significant paths toward the measured upper limb, lower limb, and other deformed joint counts (standardized regression coefficients 0.849, 0.785, 0.308, P ≤ 0.001 for each). Both the joint inflammation and joint deformity impairments displayed strong direct paths toward functional limitation (standardized regression coefficients of -0.576 and -0.564, respectively, P ≤ 0.001 for each), and explained 65% of its variance. Model fit to data was fair to good, as evidenced by a comparative fit index of 0.975, and the root mean square error of approximation = 0.058.

Conclusion

This evidence supports the occurrence of two distinct impairments in RA, joint inflammation and joint deformity, that together, contribute strongly to functional limitations in this disease. These findings may have implications for investigators aiming to measure outcome in RA.
Portals to Wonderland: Health portals lead to confusing information about the effects of health care
Authors: Glenton Claire , Paulsen Elizabeth J , Oxman Andrew D
Published: March 2005

Background

The Internet offers a seemingly endless amount of health information of varying quality. Health portals, which provide entry points to quality-controlled collections of websites, have been hailed as a solution to this problem. The objective of this study is to assess the extent to which government-run health portals provide access to relevant, valid and understandable information about the effects of health care.

Methods

We selected eight clinically relevant questions for which there was a systematic review, searched four portals for answers, and compared the answers we found to the results of the systematic reviews.

Results

Our searches resulted in 3400 hits, 155 of which mentioned both the condition and the intervention in one of the eight questions. Sixty-three of the 155 web pages did not give any information about the effect of the intervention. Seventy-seven qualitatively described the effects of the intervention. Twenty-six of these had information that was too unclear to be categorised; 15 were not consistent with the systematic review; and 36 were consistent with the review, but usually did not mention what happens without the intervention, what outcomes have been measured or when they were measured. Fifteen web pages quantitatively described effects. Four of these were abstracts from the systematic review, nine had information that was incomplete and potentially misleading because of a lack of information about people not receiving the intervention and the length of follow-up; one had information that was consistent with the review, but only referred to three trials whereas the review included six; and one was consistent with the review.

Conclusion

Information accessible through health portals is unlikely to be based on systematic reviews and is often unclear, incomplete and misleading. Portals are only as good as the websites they lead to. Investments in national health portals are unlikely to benefit consumers without investments in the production and maintenance of relevant, valid and understandable information to which the portals lead.
A model for empowerment of nursing in Iran
Authors: Adib Hajbaghery Mohsen , Salsali Mahvash
Published: March 2005

Background

While the Iranian nursing profession tries to reach to its full capacity for participating in the maintenance of public health, its desire to develop is strongly influenced by cultural, economic, and religious factors. The concept of empowerment is frequently used in nursing and the health services, particularly in relation to the quality of care, since the mission of nursing is to provide safe and quality nursing care thereby enabling patients to achieve their maximum level of wellness. When considering the importance of nursing services in any health system, the 54th World Health Assembly recommended that programs be designed to strengthen and promote the nursing profession. Since empowerment is crucial to the role of nurses, a qualitative study was conducted and aimed at designing a model for empowering nurses in Iran.

Methods

A grounded theory approach was used for analyzing the participants' experiences, their perceptions and the strategies affecting empowerment. Data collection was done through Semi-structured interviews and participant observation. Forty-four participants were interviewed and 12 sessions of observation were carried out.

Results

Three main categories emerged from the data collected; these are "personal empowerment", "collective empowerment", and "the culture and structure of the organization." From the participants' perspective, empowerment is a dynamic process that results from mutual interaction between personal and collective traits of nurses as well as the culture and the structure of the organization. Impediments, such as power dynamics within the health care system hinder nurses from demonstrating that they possess the essential ingredients of empowerment.

Conclusion

A model was designed for empowering the nursing profession in Iran. Implementing this model will not only define nursing roles, identify territories in the national healthcare system, but it will restructure nursing systems, sub-systems, and services. Currently no such model exists; therefore, restructuring of the nursing system, including its services, education and research subsystems is recommended.
Mortality registration and surveillance in China: History, current situation and challenges
Authors: Yang Gonghuan , Hu Jianping , Rao Ke Quin , Ma Jeimin , Rao Chalapati , Lopez Alan D
Published: March 2005

Background

Mortality statistics are key inputs for evidence based health policy at national level. Little is known of the empirical basis for mortality statistics in China, which accounts for roughly one-fifth of the world's population. An adequate description of the evolution of mortality registration in China and its current situation is important to evaluate the usability of the statistics derived from it for international epidemiology and health policy.

Current situation

The Chinese vital registration system currently covers 41 urban and 85 rural centres, accounting for roughly 8 % of the national population. Quality of registration is better in urban than in rural areas, and eastern than in western regions, resulting in significant biases in the overall statistics. The Ministry of Health introduced the Disease Surveillance Point System in 1980, to generate cause specific mortality statistics from a nationally representative sample of sites. Currently, the sample consists of 145 urban and rural sites, covering populations from 30,000 – 70,000, and a total of about 1 % of the national population. Causes of death are derived through a mix of medical certification and 'verbal autopsy' procedures, applied according to standard guidelines in all sites. Periodic evaluations for completeness of registration are conducted, with subsequent corrections for under reporting of deaths.

Conclusion

Results from the DSP have been used to inform health policy at national, regional and global levels. There remains a need to critically validate the information on causes of death, and a detailed validation exercise on these aspects is currently underway. In general, such sample based mortality registration systems hold much promise as models for rapidly improving knowledge about levels and causes of mortality in other low-income populations.
Vinculin acts as a sensor in lipid regulation of adhesion-site turnover
Authors: Chandrasekar Indra , Stradal Theresia E. B. , Holt Mark R. , Entschladen Frank , Jockusch Brigitte M. , Ziegler Wolfgang H.
Published: March 2005

The dynamics of cell adhesion sites control cell morphology and motility. Adhesion-site turnover is thought to depend on the local availability of the acidic phospholipid phosphatidylinositol-4,5-bisphosphate (PIP2). PIP2 can bind to many cell adhesion proteins such as vinculin and talin, but the consequences of this interaction are poorly understood. To study the significance of phospholipid binding to vinculin for adhesion-site turnover and cell motility, we constructed a mutant, vinculin-LD, deficient in acidic phospholipid binding yet with functional actin-binding sites. When expressed in cells, vinculin-LD was readily recruited to adhesion sites, as judged by fluorescence recovery after photobleaching (FRAP) analysis, but cell spreading and migration were strongly impaired, and PIP2-dependent disassembly of adhesions was suppressed. Thus, PIP2 binding is not essential for vinculin activation and recruitment, as previously suggested. Instead, we propose that PIP2 levels can regulate the uncoupling of adhesion sites from the actin cytoskeleton, with vinculin functioning as a sensor.
Internalization and recycling of ALCAM/CD166 detected by a fully human single-chain recombinant antibody
Authors: Piazza Tiziana , Cha Emanuela , Bongarzone Italia , Canevari Silvana , Bolognesi Andrea , Polito Letizia , Bargellesi Antonio , Sassi Francesca , Ferrini Silvano , Fabbi Marina
Published: March 2005

Activated leukocyte cell adhesion molecule (ALCAM/CD166), a member of the immunoglobulin superfamily with five extracellular immunoglobulin-like domains, promotes heterophilic (ALCAM-CD6) and homophilic (ALCAM-ALCAM) cell-cell interactions. Here we describe a fully human single-chain antibody fragment (scFv) directed to ALCAM/CD166. We selected the I/F8 scFv from a phage display library of human V-gene segments by cell panning and phage internalization into IGROV-I human ovary carcinoma cells. The I/F8 specificity was identified as ALCAM/CD166 by matrix-assisted laser desorption/ionisation time-of-flight (MALDI-TOF) peptide mass fingerprinting of the I/F8-immunoprecipitated protein. The I/F8 scFv reacts with the human, monkey and murine ALCAM/CD166 molecule, indicating that the recognized epitope is highly conserved. The I/F8 scFv completely abolished binding of both ALCAM/Fc and CD6/Fc soluble ligands, whereas it did not compete with the anti-ALCAM/CD166 murine monoclonal antibodies J4-81 and 3A6 and therefore recognizes a different epitope. Engagement through I/F8 scFv, 3A6 monoclonal antibody or CD6/Fc ligand induced ALCAM/CD166 internalization, with a kinetics slower than that of transferrin in the same cells. Newly internalized I/F8-ALCAM complexes colocalized with clathrin but not with caveolin and we demonstrated, using surface biotinylation and recycling assays, that endocytosed ALCAM/CD166 recycles back to the cell surface. Such an endocytic pathway allows the efficient delivery of an I/F8 scFv-saporin immunotoxin into tumor cells, as the conjugates are able to selectively kill cell lines expressing ALCAM/CD166. Altogether these data provide evidence of the suitability of the I/F8 scFv for further functional analysis of ALCAM/CD166 and intracellular delivery of effector moieties.
Do Intentions Really Predict Behavior? Self-Generated Validity Effects in Survey Research
Authors: Chandon Pierre , Morwitz Vicki G. , Reinartz Werner J.
Published: March 2005

Studies of the relationship between purchase intentions and purchase behavior have ignored the possibility that the very act of measurement may inflate the association between intentions and behavior, a phenomenon called “self-generated validity.” In this research, the authors develop a latent model of the reactive effects of measurement that is applicable to intentions, attitude, or satisfaction data, and they show that this model can be estimated with a two-stage procedure. In the first stage, the authors use data from surveyed consumers to predict the presurvey latent purchase intentions of both surveyed and nonsurveyed consumers. In the second stage, they compare the strength of the association between the presurvey latent intentions and the postsurvey behavior across both groups. The authors find large and reliable self-generated validity effects across three diverse large-scale field studies. On average, the correlation between latent intentions and purchase behavior is 58% greater among surveyed consumers than it is among similar nonsurveyed consumers. One study also shows that the reactive effect of the measurement of purchase intentions is entirely mediated by self-generated validity and not by social norms, intention modification, or other measurement effects that are independent of presurvey latent intentions.
The Effect of Expiration Dates and Perceived Risk on Purchasing Behavior in Grocery Store Perishable Categories
Authors: Tsiros Michael , Heilman Carrie M.
Published: March 2005

In this article, the authors examine consumers’ behavior with respect to expiration dates for grocery store perishable products. A better understanding of such behavior can both guide efforts to educate consumers about the risks associated with perishables that are approaching their expiration dates and help managers implement effective promotional strategies for these products throughout the course of their shelf lives. Both of these approaches can help reduce waste due to spoilage.
Conflicts in the Work–Family Interface: Links to Job Stress, Customer Service Employee Performance, and Customer Purchase Intent
Authors: Netemeyer Richard G. , Maxham James G. , Pullig Chris
Published: March 2005

Because customer service employees often represent the sole contact a customer has with a firm, it is important to examine job-related factors that affect customer service employee performance and customer evaluations. In two diverse customer settings, the authors capture matched responses from service employees, supervisors, and customers. The authors use the data to examine the potential chain of effects from customer service employee work–family conflict and family–work conflict, to job stress and job performance, to customer purchase intent (CPI). The results show direct (and indirect) effects of work–family conflict and family–work conflict on service employee customer-directed extra-role performance (CDERP). The results also show direct effects of job stress on service employee in-role performance (IRP) and CDERP and on CPI. Furthermore, the findings show that job stress has a more pronounced effect on IRP than on CDERP and that CDERP has a greater effect on CPI than does IRP. The authors conclude with a discussion of managerial and theoretical implications.
Product Development Resources and the Scope of the Firm
Authors: Wernerfelt Birger
Published: March 2005

This article examines the relationship between a firm's strength in product development and its optimal scope. Firms with product development strength have two options: They can leverage it in horizontally related markets, and they can reach into the supply chain to take full advantage of it. The question is how this should be done. One possibility is for the firm to expand its scope, and another is to manage the linkage through contracts. On the basis of the adjustment cost theory of the firm, the author argues that the former solution is more appropriate when product development is fast-paced. This study tests the argument in a sample of several thousand firms and reports four tests. For both types of expansion, the author examines the incidence and the productivity of increased scope. The author uses several measures and finds results that are consistent with the theory.
Repeat Purchasing of New Automobiles by Older Consumers: Empirical Evidence and Interpretations
Authors: Lambert-Pandraud Raphaëlle , Laurent Gilles , Lapersonne Eric
Published: March 2005

In a large empirical study, the authors find that older consumers, who constitute an important market segment, repurchase a brand more frequently when they buy a new car. Older consumers consider fewer brands, fewer dealers, and fewer models, and they choose long-established brands more often. To interpret the results, the authors rely on four age-related theoretical perspectives: biological aging, cognitive decline, socioemotional selectivity, and change aversion.
Separation of Overlapping Processes from TGA Data and Verification by EGA
Authors: Artiaga R , Cao R , Naya S , González-Martín B , Mier JL , García A
Published: March 2005

A typical problem when analyzing the kinetics by dynamic TGA of polymer degradation consists in that different models can fit equally well, or the model does not fit the TGA data. It has been suggested that this is due to the presence of overlapping processes. High resolution TGA helps to clarify the problem in some cases, but in many other cases the problem remains unsolved. In this work, a dynamic TGA curve showing overlapping processes of degradation, typical of polymer thermal degradation, is fitted by a multiple logistic regression model. The regression function is a mixture of logistic functions where each single logistic function is weighed by a factor that represents the amount of the sample that takes place in the process represented by that function. A software program was developed to fit the data to the logistic mixture model by estimation of the parameter values. Additionally, the correlation of parameter estimates was performed by the S-Plus software. The regression was performed so that the best fitting shows the number of single decomposition processes that take place along the experiment, even if they are overlapping. Other parameters have the physical meaning of mass loss rate and position of the process in the time or temperature domain. The study of the correlations of parameter estimates gives a new insight on how each component fits a logistic model. The parameters obtained describe the kinetic of the processes in a form totally independent of the Arrhenius model. The separation of processes allows for analysis of each single process by classical methods. Although the model is mathematically supported, verification was done by comparing the results with the FTIR spectra obtained from the gases evolved along the experiment. The FTIR analysis of the gases evolved from a TGA experiment confirms that the logistic mixture model is suitable to analyze a dynamic TGA trace. It was also found that the logistic mixture model is suitable to separate single components from FTIR spectra. Some differences were found in the location of the components along the time axis, comparing DTG and FTIR data. In the FTIR, the separated peaks are broader and appear shifted to longer times. It can be attributed to the delay and mixing of components that may occur during the gas carriage from the TGA furnace to the FTIR detector.
The Roles of the Caudate Nucleus in Human Classification Learning
Authors: Seger Carol A. , Cincotta Corinna M.
Published: March 2005

The caudate nucleus is commonly active when learning relationships between stimuli and responses or categories. Previous research has not differentiated between the contributions to learning in the caudate and its contributions to executive functions such as feedback processing. We used event-related functional magnetic resonance imaging while participants learned to categorize visual stimuli as predicting “rain” or “sun.” In each trial, participants viewed a stimulus, indicated their prediction via a button press, and then received feedback. Conditions were defined on the bases of stimulus-outcome contingency (deterministic, probabilistic, and random) and feedback (negative and positive). A region of interest analysis was used to examine activity in the head of the caudate, body/tail of the caudate, and putamen. Activity associated with successful learning was localized in the body and tail of the caudate and putamen; this activity increased as the stimulus-outcome contingencies were learned. In contrast, activity in the head of the caudate and ventral striatum was associated most strongly with processing feedback and decreased across trials. The left superior frontal gyrus was more active for deterministic than probabilistic stimuli; conversely, extrastriate visual areas were more active for probabilistic than deterministic stimuli. Overall, hippocampal activity was associated with receiving positive feedback but not with correct classification. Successful learning correlated positively with activity in the body and tail of the caudate nucleus and negatively with activity in the hippocampus.
Insulin-Like Growth Factor 1 Inhibits Extracellular Signal-Regulated Kinase to Promote Neuronal Survival via the Phosphatidylinositol 3-Kinase/Protein Kinase A/c-Raf Pathway
Authors: Subramaniam Srinivasa , Shahani Neelam , Strelau Jens , Laliberté Christine , Brandt Roland , Kaplan David , Unsicker Klaus
Published: March 2005

Extracellular signal-regulated kinase (ERK) activation has been shown to promote neuronal death in various paradigms. We demonstrated previously that the late and sustained ERK activation in cerebellar granule neurons (CGNs) cultured in low potassium predominantly promotes plasma membrane (PM) damage. Here, we examined the effects of a well established neuronal survival factor, insulin-like growth factor 1 (IGF-1), on the ERK cell death pathway. Stimulation of CGNs with IGF-1 induced an early and transient ERK activation but abrogated the appearance of late and sustained ERK. Withdrawal or readdition of IGF-1 after 4 h in low potassium failed to prevent sustained ERK activation and cell death. IGF-1 activated the protein kinase A (PKA) to mediate ERK inhibition via c-Raf phosphorylation at an inhibitory site (Ser259). Phosphatidylinositol 3-kinase (PI3K) or PKA inhibitors, but not a specific Akt inhibitor, abrogated PKA signaling. This suggests that the PI3K/PKA/c-Raf-Ser259 pathway mediates ERK inhibition by IGF-1 independent of Akt. In addition, adenoviral-mediated expression of constitutively active MEK (mitogen-activated protein kinase kinase) or Sindbis viral-mediated expression of mutant Raf Ser259Ala both attenuated IGF-1-mediated prevention of PM damage. Activation of caspase-3 promoted DNA damage. Its inhibition by IGF-1 was both PI3K and Akt dependent but PKA independent. 8-Br-cAMP, an activator of PKA, induced phosphorylation of c-Raf-Ser259 and inhibited ERK activation without affecting caspase-3. This indicates a selective role for PKA in ERK inhibition through c-Raf-Ser259 phosphorylation. Together, these data demonstrate that IGF-1 can positively and negatively regulate the ERK pathway in the same neuronal cell, and provide new insights into the PI3K/Akt/PKA signaling pathways in IGF-1-mediated neuronal survival.
Molecular Photoionization
Authors: Lucchese Robert R.
Published: March 2005

The computational study of molecular photoionization requires special methods due to the continuous energy spectrum and the scattering asymptotic boundary conditions required to describe the photoelectron produced in the photoionization process. Experimental observables in photoionization experiments are discussed, and the theoretical formulations for those observables are given. A survey of theoretical methods and their corresponding numerical implementations is given. Three example studies that indicate the varying size of the molecular systems and the level of detail that can be addressed using computational chemistry tools are discussed.
Compound Selection
Authors: Clark Robert D.
Published: March 2005

Chemists often find themselves needing to identify an informative subset within a larger – often, a much larger – library of compounds. The range of contexts in which such needs arise is broad, from test set selection for QSAR to compound acquisition programs. The kinds of libraries of interest vary considerably as well, from relatively small homologous data sets through vast ensembles of combinatorial libraries. Such considerations have led to development of a correspondingly wide range of compound selection methods – from simple random section through complex programs employing a genetic algorithm to balance many competing selection criteria.
Perceptual learning in adults with amblyopia: A reevaluation of critical periods in human vision
Authors: Levi Dennis M.
Published: March 2005

Critical periods for experience‐dependent plasticity are ubiquitous. The idea that experience‐dependent plasticity is closely linked with the development of sensory function is still widely held; however, there also is growing evidence for plasticity in the adult nervous system. This article reviews the notion of a critical period for the treatment of amblyopia in light of recent experimental and clinical evidence for neural plasticity. Specifically, adults with amblyopia can improve their perceptual performance via extensive practice on a challenging visual task, and this improvement may transfer to improved visual acuity. Amblyopes achieve this improvement via the mechanisms that have been shown to explain perceptual learning in the normal visual system. It is hypothesized that these same mechanisms account for at least some of the improvement that occurs in the treatment of amblyopia. © 2005 Wiley Periodicals, Inc. Dev Psychobiol 46: 222–232, 2005.
Is there a critical period for cochlear implantation in congenitally deaf children? Analyses of hearing and speech perception performance after implantation
Authors: Harrison Robert V. , Gordon Karen A. , Mount Richard J.
Published: March 2005

A range of basic and applied studies have demonstrated that during the development of the auditory system, early experimental manipulations or clinical interventions are generally more effective than those made later. We present a short review of these studies. We investigated this age‐related plasticity in relation to the timing of cochlear implantation in deaf‐from‐birth children. Cochlear implantation is a standard intervention for providing hearing in children with severe to profound deafness. An important practical question is whether there is a critical period or cutoff age of implantation after which hearing outcomes are significantly reduced. In this article, we present data from prelingually deaf children (mostly congenitally deaf) implanted at ages ranging from 1 to 15 years. Each child was tested with auditory and speech understanding tests before implantation, and at regular intervals up to 8 years postimplantation. We measured the improvement in performance of speech understanding tests in younger implanted children and compared it with the results of those implanted at a later age. We also used a binary partitioning algorithm to divide the data systematically at all ages at implant to determine the optimum split, i.e., to determine the age at implant which best separates performance of early implanted versus later implanted children. We observed distinct age‐of‐implant cutoffs, and will discuss whether these really represent critical periods during development. © 2005 Wiley Periodicals, Inc. Dev Psychobiol 46: 252–261, 2005.
Validation of adaptive unstructured hexahedral mesh computations of flow around a wind turbine airfoil
Authors: Bijl H. , van Zuijlen A. H. , van Mameren A.
Published: March 2005

In this paper we investigate local adaptive refinement of unstructured hexahedral meshes for computations of the flow around the DU91 wind turbine airfoil. This is a 25% thick airfoil, found at the mid‐span section of a wind turbine blade. Wind turbine applications typically involve unsteady flows due to changes in the angle of attack and to unsteady flow separation at high angles of attack. In order to obtain reasonably accurate results for all these conditions one should use a mesh which is refined in many regions, which is not computationally efficient. Our solution is to apply an automated mesh adaptation technique.

In this paper we test an adaptive refinement strategy developed for unstructured hexahedral meshes for steady flow conditions. The automated mesh adaptation is based on local flow sensors for pressure, velocity, density or a combination of these flow variables. This way the mesh is refined only in those regions necessary for high accuracy, retaining computational efficiency. A validation study is performed for two cases: attached flow at an angle of 6° and separated flow at 12°. The results obtained using our adaptive mesh strategy are compared with experimental data and with results obtained with an equally sized non‐adapted mesh. From these computations it can be concluded that for a given computing time, adapted meshes result in solutions closer to the experimental data compared to non‐adapted meshes for attached flow. Finally, we show results for unsteady computations. Copyright © 2005 John Wiley & Sons, Ltd.
Thyroid surgery in an area of iodine deficiency
Authors: Sarda Anil K. , Kapur Man M.
Published: March 2005

Background.

The catchment area of the patients under study was the sub‐Himalayan plains, which are recognized as iodine‐deficient areas.

Methods.

A retrospective analysis of 1576 surgically treated patients with thyroid disorders is presented. The indications for surgery were hyperthyroidism or cytologically diagnosed malignancy and large size, pressure symptoms, cosmesis, suspicious cytologic findings for malignancy, and clinical suspicion of malignancy in clinically benign euthyroid goiters.

Results.

Histologically, 83 of 703 solitary thyroid nodules, 36 of 329 clinically benign euthyroid multinodular goiters, and four of 181 Graves' disease were cancers. Of all follicular cell cancers in this study, 132 were papillary, 83 were follicular, and 38 were anaplastic and squamous cell cancers. The different histologic types exhibited an aggressive clinical behavior, with advanced lesions with cervical lymph node involvement and distant metastases frequently seen at presentation. Locoregional recurrence occurred frequently even after radical surgical ablation, and overall mortality caused by the disease was high.

Conclusions.

Even well‐differentiated cancers pursued a virulent clinical course with high mortality, despite routine radical surgical and radionuclide ablation. © 2004 Wiley Periodicals, Inc. Head Neck 27: XXX–XXX, 2005
Failure property distributions for conventional and highly crosslinked ultrahigh molecular weight polyethylenes
Authors: Kurtz S. M. , Bergström J. , Rimnac C. M.
Published: March 2005

To make stochastic (probabilistic) failure predictions of a conventional or highly crosslinked ultrahigh molecular weight polyethylene (UHMWPE) material, not only must a failure criterion be defined, but it is also necessary to specify a probability distribution of the failure strength. This study sought to evaluate both parametric and nonparametric statistical approaches to describing the failure properties of UHMWPE, based on the Normal and Weibull model distributions, respectively. Because fatigue and fracture properties of materials have historically been well described with the use of Weibull statistics, it was expected that a nonparametric approach would provide a better fit of the failure distributions than the parametric approach. The ultimate true stress, true strain, and ultimate chain stretch data at failure were analyzed from 60 tensile tests conducted previously. The ultimate load and ultimate displacement from 121 small punch tests conducted previously were also analyzed. It was found that both Normal and Weibull models provide a reasonable description of the central tendency of the failure distribution. The principal difference between the Normal and Weibull models can be appreciated in the predicted lower‐bound response at the tail end of the distribution. The data support the use of both parametric and nonparametric methods to bracket the lower‐bound failure prediction in order to simulate the failure threshold for UHMWPE. © 2005 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater
Ruthenium(III)‐catalyzed oxidation of cyclopentanol and cyclohexanol by N‐bromoacetamide
Authors: Srivastava Sheila , Awasthi Ajaya , Singh Kulina
Published: March 2005

Kinetic investigations on Ru(III)‐catalyzed oxidation of cyclopentanol and cyclohexanol by acidic solution of N‐bromoacetamide (NBA) in the presence of mercury(II) acetate as a scavenger have been carried out in the temperature range of 30–45°C. Similar kinetics was followed by both the cyclic alcohols. First‐order kinetics in the lower concentration range of NBA was observed to tend to zero order at its higher concentrations. The reaction exhibits a zero‐order rate dependence with respect to each cyclic alcohol, while it is first order in RuIII. Increase in [H+] and [Cl−] showed positive effect, while successive addition of acetamide exhibited negative effect on the reaction rate. Insignificant effect of sodium perchlorate, D2O, and mercury(II) acetate on the reaction velocity was observed. Cationic bromine has been proposed as the real oxidizing species. Various thermodynamic parameters have been computed. A suitable mechanism in agreement with the kinetic observations has been proposed. © 2005 Wiley Periodicals, Inc. Int J Chem Kinet 37: 275–281, 2005
Ferromagnets with biquadratic exchange coupling energy. Global existence of weak solutions
Authors: Hamdache K. , Hamroun D.
Published: March 2005

A global existence theorem is proved for the Landau–Lifshitz–Gilbert equations with biquadratic exchange coupling energy acting on the interfaces of a material composed by two ferromagnetic layers separated by a nonmagnetic one. This energy is not convex. The magnetization M satisfies on the interfaces a coupled non‐linear Neumann boundary condition with cubic growth. We use several regularizations, in particular for the traces of the magnetization at the interfaces, to obtain global weak solutions of the problem with finite energy. Copyright © 2005 John Wiley & Sons, Ltd.
Weak solutions for the Falk model system of shape memory alloys in energy class
Authors: Yoshikawa Shuji
Published: March 2005

We show the unique global existence of energy class solutions for the Falk model system of shape memory alloys under the general non‐linearity as well as considered in Aiki (Math. Meth. Appl. Sci. 2000; 23: 299). Our main tools of the proofs are the Strichartz type estimate for the Boussinesq type equation and the maximal regularity estimate for the heat equation. Copyright © 2005 John Wiley & Sons, Ltd.
The GADD45, ZBRK1 and BRCA1 pathway: quantitative analysis of mRNA expression in colon carcinomas
Authors: Garcia Vanesa , García José M , Peña Cristina , Silva Javier , Domínguez Gemma , Rodríguez Rufo , Maximiano Constanza , Espinosa Ruth , España Pilar , Bonilla Félix
Published: March 2005

GADD45 is a growth arrest‐associated gene that is induced in response to DNA damage. This gene is a target for coordinate regulation by both ZBRK1 and BRCA1. A sequence within intron 3 of GADD45 supports specific assembly of the ZBRK1/BRCA1 complex. In this study, the relationships between GADD45, ZBRK1, and BRCA1 expression were investigated in colon carcinomas. mRNA expression of these three genes was analysed in 116 colon carcinomas by real‐time reverse transcriptase polymerase chain reaction (RT‐PCR). Genetic and epigenetic changes that could alter expression of these genes were studied. Possible relationships between expression levels of GADD45, ZBRK1, and BRCA1, and a series of clinicopathological parameters classically associated with poor prognosis, were also examined. ZBRK1 showed a tendency towards underexpression, while GADD45 and BRCA1 were generally overexpressed. A direct relationship between these three genes was observed, with the exception of BRCA1 expression levels, similar to normal tissues, which showed a tendency to be associated with low levels of GADD45 mRNA. Concomitantly altered expression of ZBRK1 and BRCA1 was associated with GADD45 mRNA expression. Promoter hypermethylation was not observed in GADD45 or BRCA1, and no mutations in GADD45 or ZBRK1 were found in regions involved in the interaction between the GADD45 gene and the ZBRK1 and BRCA1 proteins. No clinicopathological parameter was correlated with altered GADD45 or ZBRK1 expression but there was a statistically significant relationship between BRCA1 levels and the sex of patients. In conclusion, these results suggest that this pathway, involved in the response to DNA damage, is deregulated in colon carcinomas, and concomitantly altered expression of ZBRK1 and BRCA1 has an additive effect on GADD45 regulation. This is the first study in human carcinomas to analyse the relationships between expression of GADD45, ZBRK1, and BRCA1 mRNA. Copyright © 2005 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.
CNS recurrence following CD34+ peripheral blood stem cell transplantation in stage 4 neuroblastoma
Authors: Choi Hyoung Soo , Koh Sang Hyeok , Park Eun Sil , Shin Hee Young , Ahn Hyo Seop
Published: March 2005

We report here central nervous system (CNS) recurrence in neuroblastoma (NBL) after CD34+ peripheral blood stem cell transplantation (PBSCT). Fifteen stage 4 NBL patients underwent CD34+ transplantation with myeloablative chemotherapy consisting of carboplatin, etoposide, and melphalan. There were three primary site recurrences and five distant metastases including four brain metastases (two isolated CNS recurrences) at 4–7 months after CD34+ transplantation. Three of four patients died of CNS progressive disease at 2, 8, and 9 months after recurrence and the remaining single patient was lost to follow‐up. CNS recurrence in NBL is fatal and requires identification of risk factors and more effective treatment strategies. Pediatr Blood Cancer 2005; 45:68–71. © 2005 Wiley‐Liss, Inc.
Major donors, major motives: The people and purposes behind major gifts
Authors: Schervish Paul G.
Published: March 2005

The motives of donors of large gifts are both simple and complex. What motivates the wealthy is very much what motivates someone at any point along the economic spectrum, but complexities of ability, spirituality, and association come into play in the making of major gifts.
New roles of volunteers in development
Authors: Bonnicksen Bruce C.
Published: March 2005

We all want the best possible leadership associated with our organizations. But are the best volunteers available to you? Do you still need volunteers to get the job done? Is a volunteer the best person to make the request for a major gift? What is the model for success?
Synthesis and characterization of ultraviolet‐curable hyperbranched poly(siloxysilane)s
Authors: Si Qing‐Fa , Wang Xin , Fan Xiao‐Dong , Wang Sheng‐Jie
Published: March 2005

Two UV‐curable hyperbranched poly(siloxysilane)s (I and III) containing vinyl and allyl end groups were synthesized via polyhydrosilylation with methylbis(methylethylvinylsiloxy)silane and methylbis(dimethylallylsiloxy)silane monomers. A cationic UV‐curable hyperbranched polymer (II‐Ep) with epoxy end groups was prepared via the hydrosilylation of hyperbranched polymer II with SiH terminated groups and glycidyl methacrylate, and II was also obtained via the polyhydrosilylation of AB2‐type monomer methylvinylbis(methylethylsiloxy)silane. All hydrosilylation reactions were catalyzed by Pt/C or chloroplatinic acid. Three AB2‐type monomers were synthesized via the hydrolysis of functional chlorosilane, which was prepared with Grignard reagents and dichlorosilane. The molecular structures of the polymers were characterized with 1H NMR, Fourier transform infrared, and gel permeation chromatography, and the UV‐curing behaviors of the polymers under different atmospheres and with different photoaccelerators were also investigated. The thermostability of uncured and cured polymers was examined with thermogravimetric analysis, and the data indicated that the orders of the onset decomposition temperatures for the cured polymers and the residue weights were as follows: III (380 °C) > I (320 °C) > II‐Ep (280 °C) and I (70.4%) > III (64.1%) > II‐Ep (60.9%), respectively. © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 43: 1883–1894, 2005
Dynamic structure of poly(vinyl pyrrolidone)/ethyl alcohol mixtures studied by time domain reflectometry
Authors: Sengwa R. J. , Abhilasha  , More N. M. , Mehrotra S. C.
Published: March 2005

Dielectric studies of poly(vinyl pyrrolidone)/ethyl alcohol (PVP–E) binary mixtures with concentration variations were carried out in the frequency range of 10 MHz to 10 GHz by time domain reflectometry at 15, 25, 35, and 45 °C. One relaxation process, corresponding to ethyl alcohol molecules in the poly(vinyl pyrrolidone) (PVP) matrix, was observed in this frequency range for all the mixtures. The static dielectric constant of the PVP–E mixtures decreased linearly with an increase in the weight fraction of PVP. The observed anomalous increase in the value of the relaxation time (τ) of these mixtures was interpreted by the consideration of the variation in the local structure of self‐associated ethyl alcohol molecules and also the PVP behavior as a geometric constraint for the rotational motion of ethyl alcohol molecules. Furthermore, the τ values of these mixtures were independent of the viscosity. The energy parameters for the dielectric relaxation process (the free energy, enthalpy, and entropy of activation for the dipolar orientation) were determined to confirm the transient behavior of the heterogeneous species due to the breaking and re‐forming of hydrogen bonds with the internal rotation of OH groups in the ordered structure of the PVP–E mixtures. On the basis of the evaluated dielectric parameters, the formation of supermolecular structure in the PVP–E mixtures in dynamic equilibrium was sketched and examined by the consideration of the hydrogen bonding between the terminal hydroxyl groups of self‐associated ethyl alcohol flexible chains and the carbonyl groups of monomer units of PVP coiled chains. © 2005 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 43: 1134–1143, 2005
Piezoresponse force microscopy for imaging of GaN surfaces
Authors: Calarco R. , Meijers R. , Stoica T. , Lüth H.
Published: March 2005

Surfaces of GaN films have been investigated by Atomic Force Microscopy (AFM) with implemented Piezoelectric Force Microscopy (PFM) technique. The GaN layers were grown by molecular beam epitaxy (MBE) on Si(111) substrates with an AlN buffer layer. Simultaneous imaging of surface morphology in the AFM and PFM response was performed. The PFM imaging is sensitively dependent on measurement conditions. By increasing the ac voltage the contrast of the PFM images is increased. Using the Voltage‐Modulated Force Microscopy (VMFM) regime, with the frequency close to the first resonant frequency of the piezoelectric signal, PFM images with high contrast and high resolution on the nanometer scale were obtained. Regions of opposite piezoresponse were observed and explained by the presence of inversion domains. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Pancreatoduodenectomy for Tumors of Vater’s Ampulla: Report on 94 Consecutive Patients
Authors: Giorgio Andrea Di , Alfieri Sergio , Rotondi Fabio , Prete Francesco , Miceli Dario Di , Ridolfini Marco Pericoli , Rosa Fausto , Covino Marcello , Doglietto Giovanni Battista
Published: March 2005

Evaluation of prognostic factors of adenocarcinoma of Vater’s ampulla is still a matter of debate. The aim of this study was to evaluate retrospectively factors that influence early and long‐term outcomes in a 20‐year single‐institution experience on ampullary carcinoma. A total of 94 consecutive patients with ampullary carcinoma or adenoma with severe dysplasia were managed from 1981 to 2002. Among them, 64 underwent pancreatoduodenectomy, and the remaining 30 submitted to surgical (n = 5) or endoscopic (n = 25) palliative treatment. Demographic, clinical, and pathologic data were collected, and a comparison was made between patients who did or did not undergo resection. Standard statistical analyses were carried out in an attempt to establish a correlation between clinical variables, intraoperative and pathologic factors, and survival in patients with resection. A total of 85 (90.4%) patients had potentially resectable lesions due to the extent of the tumor, but only 64 (68%) underwent curative resection. The surgical morbidity rate was 34.3%. Postoperative mortality was 9.3%, with no deaths among the 38 more recently treated patients. Median survivals were 9 and 54 months for nonresected and resected patients, respectively. The overall 5‐year survival was 64.4% for patients undergoing pancreatoduodenectomy. Survival was found to be significantly affected by resection, tumor size, tumor grade, and tumor infiltration. Patients with negative lymph nodes show a trend toward longer survival. In a multivariate analysis, only the depth of tumor infiltration influenced patient survival.

Pancreatoduodenectomy is the treatment of choice for ampullary carcinoma and adenomas with high‐grade dysplasia, with a good chance of long‐term survival. Surgical resection remains the most important factor influencing outcome.
Usefulness of Thyroglobulin Measurement in Fine‐needle Aspiration Biopsy Specimens for Diagnosing Cervical Lymph Node Metastasis in Patients with Papillary Thyroid Cancer
Authors: Uruno Takashi , Miyauchi Akira , Shimizu Kazuo , Tomoda Chisato , Takamura Yuuki , Ito Yasuhiro , Miya Akihiro , Kobayashi Kaoru , Matsuzuka Fumio , Amino Nobuyuki , Kuma Kanji
Published: March 2005

The diagnosis of lymph node metastasis in patients with papillary thyroid cancer is an important factor when deciding to perform neck dissection at the initial surgery, as well as for evaluating the lymph node swelling after surgery. Ultrasound (US)‐guided fine‐needle aspiration biopsy cytology (FNAB‐C) is the most useful technique for diagnosing lymph node metastasis. Recently, however, measurement of thyroglobulin in the wash‐out of the needle (FNAB‐Tg) has been proposed for early detection of neck lymph node metastasis in patients with differentiated thyroid cancer. The purpose of this study was to evaluate the usefulness of FNAB‐Tg in detecting lymph node metastasis prior to initial or reoperative thyroid surgery. US‐guided FNAB‐C was performed on 129 enlarged lymph nodes of 111 patients before surgery. All of them were later histologically confirmed to contain metastasis. Immediately after obtaining an FNAB‐C specimen, the needle was rinsed with 0.5 ml of normal saline solution, and the wash‐out was subjected to measurement of the Tg level (FNAB‐Tg). If the FNAB‐Tg level was higher than the serum Tg of the patient, we diagnosed the lymph node as positive (metastatic lymph node). FNAB‐Tg sensitivity was 81.4%, and FNAB‐C sensitivity was 78.0%. Altogether, 4 (36.4%) of 11 cases judged “benign” and 6 (37.5%) of 16 cases judged “inadequate” by FNAB‐C were positive by the FNAB‐Tg measurement. Thyroglobulin measurement in fine‐needle aspiration biopsy wash‐out is thus a useful technique for diagnosing lymph node metastasis of papillary thyroid cancer.