bluuebunny/crossref_metadata_2025 huggingface dataset:
Bupropion May Support Psychosocial Treatment of Nicotine‐Dependent Adolescents: Preliminary Results
Authors: Niederhofer Helmut , Huber Markus
Published: October 2004

Study Objective. To assess the efficacy and safety of long‐term bupropion therapy for nicotine dependence in adolescents.

Design. Prospective, double‐blind, placebo‐controlled trial.

Setting. Outpatient clinic in Innsbruck, Austria.

Subjects. Twenty‐two adolescents, aged 16–19 years, with nicotine dependence.

Intervention. Participants were randomly assigned to receive bupropion 150 mg/day or placebo for 90 days.

Measurements and Main Results. Patients were classified as abstinent or relapsed on day 0 (when study drug was started) and again on days 30 and 90, according to their self‐reports. Treatment failure was defined as relapse or nonattendance. Time to first treatment failure was the primary outcome measure. Mean cumulative abstinence duration was significantly greater in the bupropion group than in the placebo group (78.4 ± 39.6 vs 30.2 ± 19.2 days. p=0.0042).

Conclusion. Bupropion seems to be an effective and well‐tolerated pharmacologic adjunct to psychosocial and behavioral treatment programs for some adolescent nicotine‐dependent patients. However, experienced clinicians should continuously monitor patients for adverse effects.
Magnitude and Duration of Elevated Gastric pH in Patients Infected with Human Immunodeficiency Virus After Administration of Chewable, Dispersible, Buffered Didanosine Tablets
Authors: DePestel Daryl D. , Kazanjian Powel H. , Cinti Sandro K. , Kauffman Carol A. , Carver Peggy L.
Published: October 2004

Study Objectives. To test the hypothesis that gastric pH would be elevated above pH 3.0 for at least 2 hours after administration of chewable, dispersible, buffered didanosine tablets. Doses tested were 200 mg (two 100‐mg tablets) and 400 mg (two 200‐mg tablets). We also sought to compare these doses with regard to maximum gastric pH (pHmax), time to pHmax (TpH‐max), time that gastric pH exceeds 3.0 (TpH>3), and area under the gastric pH versus time curve for pH greater than 3.0 (AUCT>pH 3).

Design. Prospective, parallel‐group, dose‐comparison, gastric pH study.

Setting. General Clinical Research Center, University of Michigan Hospitals, Ann Arbor, Michigan.

Patients. Nineteen patients infected with human immunodeficiency virus, aged 30–62 years, and receiving long‐term didanosine therapy.

Intervention. Patients underwent continuous gastric pH monitoring, using the Heidelberg capsule radiotelemetric pH monitoring device. After documentation of a fasting baseline gastric pH below 3.0, patients were given 180 ml of water (control phase), and gastric pH was allowed to return to baseline. After administration of a single, oral dose of didanosine 200 mg or 400 mg with 180 ml of water, gastric pH was recorded until pH remained below 3.0 for 10 minutes.

Measurements and Main Results. A mean pHmax of 8.6 (range 6.3–9.5) was achieved with a TpH‐max of 4.1 minutes (range 1–12.0 min). Mean TpH>3 was 24.9 minutes (range 15–55 min), with an AUCT>pH 3 of 2.6 pH•min−1 (range 1.2–6.9 pH•min−1). The two doses of didanosine tested did not differ significantly in mean gastric pH parameters.

Conclusions. After administration of chewable, dispersible, buffered didanosine tablets, 200 or 400 mg, the mean duration of elevated gastric pH (TpH>3) was less than 30 minutes, with a range of 15–55 minutes. Characterization of the magnitude and duration of elevated gastric pH may allow for earlier administration of other pH‐sensitive drugs. The short duration of elevated gastric pH may help explain the wide variability in didanosine bioavailability observed clinically.
Follow‐up of Adverse Drug Reactions from Peginterferon alfa‐2b—Ribavirin Therapy
Authors: Bagheri Haleh , Fouladi Atoussa , Barange Karl , Lapeyre‐Mestre Maryse , Payen Jean‐Louis , Montastruc Jean Louis , Vinel Jean‐Pierre
Published: October 2004

Study Objective. To investigate the adverse drug reactions (ADRs) from peginterferon alfa‐2b plus ribavirin in patients infected with the hepatitis C virus (HCV).

Design. Prospective, observational, pharmacovigilance study.

Setting. Gastroenterology department of a French university hospital.

Patients. A cohort of consecutive outpatients who were treated with peginterferon alfa‐2b plus ribavirin for viral hepatitis.

Intervention. During the 1‐year period of HCV therapy visits, a medical staff member trained in pharmacovigilance interviewed the patients about all ADRs and their use of other drugs. The ADRs assessed as serious were confirmed from regular review of the medical records.

Measurements and Main Results. A total of 87 patients were treated for HCV. Among these, peginterferon alfa‐2b plus ribavirin therapy was started in 51 patients; one patient was lost to follow‐up after 1 month. The ADRs were assessed as serious in 10 patients (20%): suicide (one patient), hospitalization (three patients), and definitive discontinuation of peginterferon alfa‐2b plus ribavirin (six patients). The ADRs contributed to or were the main reason for withdrawing HCV drugs in 8 patients (16%). Dosage reductions of ribavirin and/or peginterferon alfa‐2b were required in 10 patients (20%) and seemed less frequent than that needed in clinical trials. Compared with results of clinical trials, a similar frequency of hair loss, higher frequency of injection‐site reactions, lower frequency of depression or insomnia, and higher frequency of endocrine ADRs or blurred vision were detected.

Conclusion. Results suggest some differences in the frequencies of ADRs compared with data from clinical trials. A longer period of monitoring is warranted to improve knowledge about ADRs of pegylated interferon. A medical staff member trained in pharmacovigilance is useful to collect quantitative and qualitative data about ADRs.
Drug‐Eluting Stents: A Mechanical and Pharmacologic Approach to Coronary Artery Disease
Authors: Dobesh Paul P. , Stacy Zachary A. , Ansara Alexander J. , Enders Jason M.
Published: October 2004

Coronary artery disease is the largest killer of men and women in the United States and costs the health care system billions of dollars annually. Several advances in both mechanical and pharmacologic treatment of coronary artery disease have occurred in recent decades. Mechanically, percutaneous coronary intervention is commonly used to treat coronary atherosclerosis. This approach has dramatically reduced both morbidity and mortality for patients with different levels of severity of coronary artery disease. However, percutaneous coronary intervention is limited by restenosis, which is an increase in growth of the intimal layer of the vessel wall. Despite the introduction of intracoronary stents and the addition of systemic pharmacotherapy, restenosis still affects a significant number of patients. The new technology of drug‐eluting stents combines mechanical and pharmacologic approaches to prevent restenosis. Various types of these stents exist in different stages of development; several have been shown to prevent or reduce intimal growth after stent deployment. An understanding of how this combined mechanical and pharmacologic approach reduces restenosis requires consideration of complex issues in pathophysiology and pharmacology.
Intravenous Ethanol for the Treatment of Alcohol Withdrawal Syndrome in Critically Ill Patients
Authors: Hodges Brian , Mazur Joseph E.
Published: October 2004

Critically ill patients with alcoholism are at greater risk of morbidity and mortality from alcohol withdrawal syndrome than are patients without alcoholism. Benzodiazepines are considered the drugs of choice for the prevention and treatment of alcohol withdrawal syndrome, but some studies have suggested that intravenous ethanol may be as effective as those agents, as well as being less sedating. We evaluated the evidence regarding the use of intravenous ethanol for the prevention and treatment of alcohol withdrawal syndrome in critically ill patients in order to determine its role in this patient population. Because of the paucity of well‐designed clinical trials, and because of intravenous ethanol's questionable efficacy, inconsistent pharmacokinetic profile, and relatively narrow therapeutic index, routine use of this drug is not recommended in critically ill patients who have alcohol withdrawal syndrome or are at risk for it.
Key References in Infectious Diseases Pharmacotherapy
Authors:   Behalf of the American College of Clinical Pharmacy Infectious Diseases Practice and Research Network Bibliography Group, Drew Richard H.
Published: October 2004

Most health care practitioners are challenged to maintain knowledge of contemporary practice issues in many therapeutic disciplines. Like many other areas, infectious diseases pharmacotherapy continues to evolve because of new information regarding disease epidemiology and new treatment options. Emerging infections and resistance further compound the need for information. To assist clinicians in identifying such important new information, we compiled a list of key references on infectious diseases pharmacotherapy published over the last 2 years.
High‐Impact Articles Related to the Pharmacotherapeutic Management of Systolic Heart Failure
Authors: Ng Tien M. H. , Carter Orly , Guillory Gregory S. , Howard Patricia A. , Lee Craig R. , Rodgers Jo E. , Uber Patricia A. , Wiggins Barbara S. , Munger Mark A. , Patterson J. Herbert
Published: October 2004

This compilation is part of a series of five articles identifying important literature in cardiovascular pharmacotherapy. This list focuses on pharmacotherapeutic management of acute decompensated and chronic heart failure. Most of the cited works present the results of landmark clinical studies that have shaped the management of patients with left ventricular systolic dysfunction. Limited primary literature is available for some topics; thus, pertinent review articles also are listed. In addition, consensus documents formed by expert panels in the United States and Europe are reviewed. This compilation may serve as a teaching tool, reference resource, or update of the literature for pharmacy clinicians, physicians, and students.
Interaction Between Nesiritide and a Heparin‐Coated Pulmonary Artery Line During an Infusion for Decompensated Heart Failure
Authors: Baroletti Steven A. , Wahlstrom Heather D.
Published: October 2004

Study Objective. Because it is known that intravenous nesiritide is not compatible with unfractionated heparin, we sought to determine the effect that heparin coating on a pulmonary artery catheter may have on the efficacy of a nesiritide infusion.

Methods. The efficacy of a nesiritide infusion given through a heparin‐coated pulmonary artery line was compared with that of a nesiritide infusion administered in the same patient through a heparin‐free peripheral line.

Results. The rate of infusion was titrated to maintain consistent hemodynamic parameters. When nesiritide was administered through a heparin‐coated line, the infusion rate escalated from 0.01 μg/kg/minute to 0.07 μg/kg/minute. After the route of administration was switched to a heparin‐free line, the same hemodynamic parameters were maintained. The heparin‐free line made it possible to reduce the infusion rate by 57.1% over the next 24 hours to 0.03 μg/kg/minute.

Conclusion. The interaction of nesiritide with heparin‐coated pulmonary artery lines has the potential to be clinically significant. Clinicians should be educated about this potential interaction. Nesiritide should be infused only through heparin‐free lines.
Benefit of Ribose in a Patient with Fibromyalgia
Authors: Gebhart Benjamin , Jorgenson James A.
Published: October 2004

Ribose was added to the existing treatment regimen of a woman with fibromyalgia, resulting in a decrease in symptoms. It has been postulated that patients with fibromyalgia may have an alteration in muscle adenine nucleotide metabolism, leading to depleted energy reserves and an imbalance in cellular adenosine 5′‐triphosphate:adenosine 5′‐diphosphate:adenosine 5′‐monophosphate (ATP:ADP:AMP) ratios with an abnormal energy charge. As a key component in adenine nucleotide synthesis, ribose supplementation may be useful in such patients.
Vengeance: Effects of gender, age, and religious background
Authors: Cota‐McKinley Amy L. , Woody William Douglas , Bell Paul A.
Published: October 2004

Vengeance can be commonly defined as the infliction of harm in return for perceived injury or insult or as simply getting back at another person. Three hundred fifty‐three participants responded to eight hypothetical scenarios that may elicit vengeful behavior in which the offending party was either a romantic partner, a friend, a coworker, or a stranger. Participants also completed a vengeance scale and a measure of biblical literalism. Participants were most vengeful toward coworkers and least vengeful toward romantic partners. Age, religious conservatism, and gender were significant predictors of attitudes toward vengeance. Although men were more likely than women to be accepting of vengeful attitudes as measured by the vengeance scale, only age was a significant predictor of behavior in the vengeance scenarios. The current research provides a basis for a systematic investigation of vengeance within the structure of human relationships and interactions. Aggr. Behav. 27:343–350, 2001. © 2001 Wiley‐Liss, Inc.
Inhibition of aggression by progesterone and its metabolites in female Syrian hamsters
Authors: Kohlert Jess G. , Meisel Robert L.
Published: October 2004

The sequence of estradiol and progesterone is known to inhibit the expression of aggression in female hamsters. Despite the key importance of progesterone in the inhibition of aggression, little is known of the mechanisms through which progesterone may exert this effect. Three experiments were performed to assess the degree to which metabolites of progesterone can affect aggression in female Syrian hamsters. Systemic estradiol treatment followed by injections of either progesterone (300 μg IP) or 4‐pregnen‐21‐ol‐3,20‐dione (DOC, 300 μg IP) reliably inhibited aggression. Systemic injection (75, 150, or 300 μg IP) of either 5α‐pregnan‐3α,21‐diol‐20‐one (THDOC) or 5α‐pregnan‐3α‐ol‐20‐one (3α,5α‐THP) did not affect aggression. Intracerebroventricular infusion of 3α,5α‐THP following systemic estradiol treatment also did not affect aggression. In a third experiment, female hamsters were given systemic treatments with estradiol and progesterone that were subthreshold with respect to inhibition of aggression. In these females, intracerebroventricular infusion of THDOC inhibited aggression. These results indicate that metabolites of progesterone can inhibit aggression, most notably in synergy with progesterone itself. Aggr. Behav. 27:372–381, 2001. © 2001 Wiley‐Liss, Inc.
Personal and participatory socializers of the perceived legitimacy of aggressive behavior in sport
Authors: Conroy David E. , Silva John M. , Newcomer R. Renee , Walker Brent W. , Johnson Matthew S.
Published: October 2004

Recent international attention from the media and professional organizations has focused increasingly on violent incidents in sport. The present study developed and used the Sport Behavior Inventory (SBI) to examine personal and participatory variables that influence the socialization of the perceived legitimacy of aggressive sport behavior in children and adolescents ages 8–19 enrolled in public schools. In phase I of this study, the psychometric properties of the SBI as a measure of perceived legitimacy were evaluated in terms of content validity, structural validity, internal consistency, convergent validity, and discriminant validity. A multiple regression analysis in phase II indicated that increases in athletes’ perceptions of the legitimacy of aggressive sport behavior were positively related to age, being male, and contact sport participation. Results were discussed in relation to the social factors that contribute to the development of perceptions of legitimacy for aggressive sport behavior, and future research uses for the SBI. Aggr. Behav. 27:405–418, 2001. © 2001 Wiley‐Liss, Inc.
Mixtures of Ionic Liquids and Water as a Medium for Efficient Enantioselective Hydrogenation and Catalyst Recycling
Authors: Pugin B. , Studer M. , Kuesters E. , Sedelmeier G. , Feng X.
Published: October 2004

In a screening of ligands, ionic liquids and reaction conditions in the Rh‐catalyzed hydrogenation of enamides, a novel multi‐phase reaction system consisting of an ionic liquid (IL) and water (wet ILs) was found to give the most promising results. In many cases such IL/water combinations were superior compared to conventional organic solvents and biphasic ILs/organic co‐solvents media with respect to catalytic performance as well as to catalyst separation and recycling. So far, the best results were obtained with Rh‐ferrocenyl‐diphosphine catalysts (>99% ee). Generally, somewhat lower ees were observed at higher pressure. However, this effect was less pronounced with wet ILs than with conventional solvents. It is shown that IL/water combination allow repeated catalyst recycling without significant loss of activity and that industrially relevant turnover numbers of >10,000 can be obtained.
A Highly Regioselective Preparation of 4‐Chloromethyl‐5‐methyl‐2‐aryl‐1,3‐oxazoles
Authors: Lee George T. , Jiang Xinglong , Vedananda T. R. , Prasad Kapa , Repič Oljan
Published: October 2004

A facile highly regioselective process is described for the formation of 4‐chloromethyl‐1,3‐oxazoles from 1,3‐oxazole N‐oxide/HCl salts. An explanation is presented for the high regioselectivity in deoxygenation‐chlorination using POCl3 with HCl salts compared to the corresponding free N‐oxides. The method is quite general and the products are isolated by direct precipitation in all cases studied.
The Unusual Characteristics of the Aerobic Oxidation of 3,4‐Dimethoxytoluene with Metal/Bromide Catalysts
Authors: Partenheimer Walt
Published: October 2004

DMtoluene (3,4‐dimethoxytoluene; DM=3,4‐dimethoxy), a model compound for lignin oxidation, can be autoxidized in acetic acid using a Co/Mn/Br catalyst to its benzaldehyde in 51 mol % yield, and to its acid in 85–92 mol % yield. This synthesis is unusual because a number of unprecedented phenomena occur. 1) The rate of molecular oxygen reacting with the substrate is bi‐phasic, i.e., two maximum in the rate of reaction are observed. 2) In the first phase, all of the 3,4‐dimethoxytoluene is converted to intermediates, but very little to the carboxylic acid. 3) During the second maximum of activity, virtually all the intermediates are converted to the carboxylic acid with 95–100% mass accountability. 4) The rate of carbon monoxide and carbon dioxide formation is considerably higher during the second phase during which 5) 9–12% of methyl 3,4‐dimethoxybenzoate (the methyl ester of the benzoic acid) is formed. Mechanisms are suggested for these unusual phenomena.
Dendronized Poly(Ru‐BINAP) Complexes: Highly Effective and Easily Recyclable Catalysts For Asymmetric Hydrogenation
Authors: Deng Guo‐Jun , Yi Bing , Huang Yi‐Yong , Tang Wei‐Jun , He Yan‐Mei , Fan Qing‐Hua
Published: October 2004

A new kind of dendronized polymeric chiral BINAP ligands has been synthesized and applied to the Ru‐catalyzed asymmetric hydrogenation of simple aryl ketones and 2‐arylacrylic acids. These dendronized poly(Ru‐BINAP) catalysts exhibited high catalytic activity and enantioselectivity, very similar to those obtained with the corresponding parent Ru(BINAP) and the Ru(BINAP)‐cored dendrimers. It was found that the pendant dendrons had a major impact on the solubility and the catalytic properties of the polymeric ligands. These polymeric catalysts could be easily recovered from the reaction solution by using solvent precipitation, and the reused catalyst showed no loss of activity or enantioselectivity.
Palladium‐Carbene Catalysts for Aerobic, Intramolecular Wacker‐Type Cyclisation Reactions
Authors: Muñiz Kilian
Published: October 2004

A catalyst derived from in situ complexation of N‐heterocyclic carbenes to palladium bistrifluoroacetate promotes efficient intramolecular Wacker‐type cyclisation reactions under aerobic conditions. A variety of 2‐allylphenols undergo oxidative conversion to dihydrobenzofurans.
Changes in foot and mouth disease status and evolving world beef markets
Authors: Ekboir Javier , Jarvis Lovell S. , Sumner Daniel A. , Bervejillo José E. , Sutton William R.
Published: October 2004

Argentina and Uruguay eradicated foot and mouth disease (FMD) in 2000 and 1995, and subsequently gained greater access to FMD‐free markets. Although both South American countries suffered from the reintroduction of FMD in late 2000, and had to temporarily cease exports to FMD‐free markets, they are expected to eradicate FMD again and will continue to increase exports to FMD‐free markets. This article analyzes the changes in international beef trade and, especially, in beef prices that are expected. We use a simulation model that captures the effects of market segmentation due to the FMD status and of the trade policies of exporting and importing countries. The ongoing realignment of trade flows has potential to significantly affect prices in both the FMD‐free and the FMD‐endemic segments of the world beef market. We demonstrate how growing beef exports from South America to FMD‐free markets interact with other on‐going changes in international beef markets. © 2002 Wiley Periodicals, Inc. [EconLit citations: Q110: Agriculture, Aggregate Supply and Demand; Q170: Agriculture, International Trade]
A repositioning strategy for olive oil in the UK market
Authors: Martínez Marian García , Aragonés Zulema , Poole Nigel
Published: October 2004

Despite a rapid growth in olive oil consumption in recent few years, the culinary use of olive oil is still relatively new to UK consumers, and is still regarded as a set of particular attributes rather than as an everyday cooking oil. To increase sales and attract new users, olive oil needs to be seen by UK consumers as an ‘everyday’ cooking oil, and enter into direct competition with standard vegetable oils. To achieve this, we argue in this paper that standard olive oil needs to be repositioned and distanced from extra virgin olive oil in order to give customers sufficient cues to revise their opinions and consumption strategies. The objective of this paper is to report the results of a conjoint study as a tool for the analysis of attribute trade‐offs made in product choices by consumers, applied to the UK standard olive oil market. The ideal standard olive oil profile for 130 UK users of olive oil was found to be one packed in medium sized PET bottles (750 ml) at a price of £2.99. [Econ‐Lit citations: M310, M370]. © 2002 Wiley Periodicals, Inc.
Dyssegmental dysplasia, Silverman‐Handmaker type: Unexpected role of perlecan in cartilage development#
Authors: Arikawa‐Hirasawa Eri , Wilcox William R. , Yamada Yoshihiko
Published: October 2004

Dyssegmental dysplasia, Silverman‐Handmaker type (DDSH), is a lethal autosomal recessive form of dwarfism with characteristic anisospondylic micromelia. The remarkable similarities in the radiographic, clinical, and chondroosseous morphology of DDSH patients to those of perlecan‐null mice led to the identification of mutations in the perlecan gene (HSPG2) of DDSH. Perlecan, a large heparan sulfate proteoglycan, is expressed in various tissues and is a component of all basement membrane extracellular matrices. A chondrodysplasia phenotype caused by the loss of perlecan was unexpected, because cartilage does not have basement membranes. Insertion and splicing mutations in HSPG2 of DDSH were found that were predicted to create a premature termination codon. Immunostaining and biochemical analysis revealed that the mutant perlecan molecules were unstable and not secreted into the extracellular matrix. These results indicate that DDSH is caused by functional null mutations of HSPG2 and that perlecan is essential for cartilage development. Published 2002 Wiley‐Liss, Inc.
Endohedrale Zintl‐Ionen: intermetalloide Cluster
Authors: Fässler Thomas F. , Hoffmann Stephan D.
Published: October 2004

Tetrele sind aussichtsreiche Kandidaten für den Aufbau größerer Cluster. Jüngste Beispiele zeigen, dass solche Cluster durch ein Zentralatom stabilisiert werden können, wie durch [Pt@Pb12]2− belegt wird. Viele Salze der polyedrischen Anionen sind löslich, andere – in der Regel die höher negativ geladenen Vertreter – sind aber nur als quasi diskrete Einheiten in ionogenen Kristallverbänden (Zintl‐Phasen) oder als Baugruppen in intermetallischen Phasen beobachtet worden. In diesem Kurzaufsatz wird die Chemie der intermetalloiden Cluster im Zusammenhang mit den Systemen der endohedralen Zintl‐Ionen, Zintl‐Phasen und polyedrischen Baueinheiten intermetallischer Verbindungen sowie der heteroatomaren Gasphasen‐Spezies an ausgewählten Beispielen beleuchtet und im Kontext mit den Fortschritten auf dem Gebiet metalloider Cluster und (endohedraler) Fullerene und Fulleride diskutiert.
Endohedral Zintl Ions: Intermetalloid Clusters
Authors: Fässler Thomas F. , Hoffmann Stephan D.
Published: October 2004

Tetrels can be regarded as most promising candidates for the construction of larger clusters. Recent examples have shown that larger clusters are particularly stable if they contain interstitial atoms (e.g. [Pt@Pb12]2−). Many salts of the polyhedral anions are soluble, but a number of examples—usually those with higher charges—occur only as quasi‐discrete units in saltlike crystals (Zintl phases) or as building blocks in intermetallic phases. In this Minireview, the chemistry of intermetalloid clusters is reviewed with reference to the endohedral Zintl ions, Zintl phases, and polyhedral building blocks of intermetallic compounds, including heteroatomic species in the gas phase. We focus on selected examples and discuss the new findings in the context of recent advances in the field of metalloid clusters and (endohedral) fullerenes and fullerides.
Creep and shrinkage behavior of improved ultrathin polymeric films
Authors: Higashioji Takuji , Bhushan Bharat
Published: October 2004

Long‐term creep‐deformation and shrinkage characteristics of improved ultrathin polymeric films for magnetic tapes are presented. These films include poly(ethylene terephthalate) (PET), poly(ethylene naphthalate) (PEN), and aromatic polyamide (ARAMID). PET film is currently the standard substrate used for magnetic tapes, and thinner tensilized‐type PET, PEN, and ARAMID have recently been used as alternate substrates with improved material properties. The thickness of the films ranges from 6.2 to 4.8 μm. More dimensional stability is required for advanced magnetic tapes, and the study of creep and shrinkage behavior is important for estimating the dimensional stability. Creep measurements were performed on all available substrates at 25, 40, and 55°C for 100 h. Based on these data, master curves were generated using time–temperature superposition to predict dimensional stability after several years. The amount of creep deformation is considerably smaller for ARAMID and tensilized‐type PET than for PEN, although Standard PET shows the largest amount of creep. In addition, creep measurements under high humidity also show similar trends. Shrinkage measurements at 55°C for 100 h show that the shrinkage of ARAMID is lower than that of PET and PEN. The relationship between the polymeric structure and dimensional stability are also discussed. Based on the creep and shrinkage behavior, ARAMID and tensilized‐type PET seem to be suitable for advanced magnetic tapes. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 84: 1477–1498, 2002; DOI 10.1002/app.10012
Structure and ionic conductive properties of polydioxolane–polyurethane‐based electrolytes
Authors: Zhu Weihua , Yang Bing , Wang Xinling , Wang Lei , Tang Xiaozhen , Yang Changzheng
Published: October 2004

A series of polyurethanes (PUs) with different polyether soft segments [polydioxolane (PDXL), polyethylene glycol (PEG), or PDXL/PEG] were synthesized successfully, and solid polymer electrolytes based on PU/LiClO4 complexes were prepared. The relations between structure and the ionic conductive properties of the PU‐based electrolytes were investigated by means of Fourier transform infrared spectroscopy, differential scanning calorimetry, dynamic mechanical analysis, and complex impedance analysis. Results showed that the glass‐transition temperature (Tg) of PDXL–PU was lower than that of PEG–PU. Doped lithium perchlorate (LiClO4) salt could be dissolved well in soft segments of PDXL–PU. The ionic conductivity of the PDXL–PU/LiClO4 complex could reach a value of 2 × 10−5 S/cm at room temperature without the addition of an organic plasticizer. The system with PDXL/PEG as a soft segment had a higher Tg and a lower ionic conductivity than the one with PDXL as a soft segment. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 83: 103–111, 2002
Isothermal gravimetric analysis of poly(trimethylene terephthalate)
Authors: Wang Xue‐Song , Li Xin‐Gui , Yan Deyue
Published: October 2004

Poly(trimethylene terephthalate) was investigated by isothermal thermogravimetry in nitrogen at six temperatures, including 304, 309, 314, 319, 324, and 336°C. The isothermal data have been analyzed using both a peak maximum technique and an iso‐conversional procedure. Both techniques gave apparent activation energies of 201 and 192 kJ mol−1, respectively, for the isothermal degradation of poly(trimethylene terephthalate) in nitrogen. The decomposition reaction order is calculated to be 1.0. The natural logarithms of the frequency factor based on the peak maximum and the iso‐conversional techniques are 36 and 34 min−1, respectively, for poly(trimethylene terephthalate) decomposed isothermally in nitrogen. These isothermal kinetic parameters are in good agreement with those derived by the Kissinger technique on the basis of the dynamic thermogravimetric data reported elsewhere (209 kJ mol−1, 1.0 and 37 min−1). The isothermal decomposition of poly(trimethylene terephthalate) in nitrogen undergoes two processes, a relative fast degradation process in the initial period and a subsequent one with a slower weight‐loss rate. The former process may be due to the removal of ester groups, trimethylene groups, and aromatic hydrogen atoms from the chain of poly(trimethylene terethphalate). The latter one may be ascribed to the further pyrolysis of the carbonaceous char. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 84: 1600–1608, 2002; DOI 10.1002/app.10476
Melt‐spinning process of a tetrafluoroethylene– hexafluoropropylene copolymer
Authors: Uno Taiko , Miyata Seizo , Shirai Hirohusa
Published: October 2004

An industrial melt‐spinning process of tetrafluoroethylene– hexafluoropropylene copolymer (FEP) using an extruder was studied. The novel “spinneret,” having both a large‐diameter spinning nozzle and a high‐temperature vessel, was used to solve the problem of filament breakage on the spinning line caused by high melting viscosity of FEP. The extruder, with its long feed zone, was newly designed to function with a geared pump. The strength of fibers increased with drawing of as‐spun fiber. FEP fibers up to six denier were continuously produced through long‐run production. According to this new process, FEP fibers can be supplied for textile or industrial application. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 84: 2366–2371, 2002
Evolution of molecular weight and molecular weight distribution in ab initio styrene emulsion polymerizations using series of rigid rodlike cationic amphiphiles as surfactants
Authors: Zaragoza‐Contreras Erasto Armando , Navarro‐Rodríguez Dámaso , Maldonado‐Textle Hortensia
Published: October 2004

The emulsion polymerization of styrene is carried out using a series of unconventional rigid rodlike cationic surfactants (1‐[ω‐(4′‐methoxy‐4‐biphenylyloxy)alkyl]pyridinium bromides, PCX) of different lengths. The evolution of the molecular weight (M) and molecular weight distribution of the polymers is analyzed to obtain information about the chain stopping mechanism. Our results indicate that the M is strongly dependent on the initial surfactant concentration and is not dependent on the alkyl chain length. The Clay and Gilbert model [ln P(M) versus M plots] yields a concave‐up region at low molecular weights and a linear region that extends to high values. The slope of the linear region, which is related to the rate coefficient of the chain transfer to the monomer versus the propagation rate coefficient ratio, decreases as the PCX concentration increases. This behavior indicates that as the PCX concentration increases the chain transfer to monomer becomes the dominant chain stopping mechanism. On the other hand, the ln P(M) versus M plots of polymer samples taken at low and high conversions show differences in slope, particularly at low PCX concentration. It is likely that at low conversion the chain transfer to monomer competes with other chain stopping mechanisms that could be associated with a coagulative nucleation process. The formation of a high molecular weight fraction at low conversion supports this explanation. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 84: 1513–1523, 2002; DOI 10.1002/app.10489
The effect of particle concentration of poly(p‐phenylene) on electrorheological response
Authors: Sohn Jeong‐In , Sung Jun H. , Choi Hyoung J. , Jhon Myung S.
Published: October 2004

Poly(p‐phenylene) (PPP) particle‐based electrorheological (ER) fluids were prepared from FeCl3‐doped PPP and silicone oil. The effect of the volume fraction of PPP and applied electric field strength on ER response was investigated via measured rheological properties, including flow curve, shear viscosity, and yield stress. Furthermore, the yield stresses of the PPP‐based ER fluid, which exhibit the typical characteristics of a Bingham fluid, were measured. The yield stress data collapse on a universal scaling function proposed by Choi et al. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 84: 2397–2403, 2002
Synthesis and characterization of urethane/acrylate composite latex
Authors: Wu Limin , You Bo , Li Dan
Published: October 2004

Polyurethane dispersion and urethane/acrylate composite latex were synthesized and characterized by using a particle size analyzer, gel permeation chromatograph (GPC), Fourier transform infrared spectroscopy coupled with attenuated total reflectance (FTIR‐ATR), dynamic mechanical analysis (DMA), and instron test machine. The amount of solvent and dimethylolpropionic acid (DMPA) used during synthesis of polyurethane resin straightway affected the average particle size and stability of aqueous polyurethane dispersion. The particle size of polyurethane dispersion had nothing to do with that of composite latex. FTIR‐ATR analyses displayed both air‐facing and substrate‐facing surfaces, containing more polyurethane component than the average composition. Some crosslinking reactions occurred in preparing urethane/acrylic composite latex, as indicated by FTIR analyses and solvent extraction. DMA demonstrated three glass transitions for the film from composite latex. Instron tests exhibited better film performance properties for the composite latex than for the corresponding blend latex. A possible particle growth mechanism for preparing urethane/acrylate composite latex was proposed. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 84: 1620–1628, 2002; DOI 10.1002/app.10526
Ultrasonic improvement of rheological behavior of polystyrene
Authors: Chen Guangshun , Guo Shaoyun , Li Huilin
Published: October 2004

The effects of ultrasonic oscillation on die pressure, productivity of extrusion, melt viscosity, and melt oscillating flow of polystyrene (PS) as well as their mechanism were studied in a special ultrasonic oscillations extrusion system developed in our lab. The experimental results show that in the presence of ultrasonic oscillations, the PS melt oscillating flow or surface distortion of PS extrudate is inhibited or disappears. The surface appearance of PS extrudate gets greatly improved. The die pressure, melt viscosity, flow activation energy, and consistency efficiency of PS decreased and the productivity of PS extrudate increased in the presence of ultrasonic oscillation. The shear sensitivity of PS melt viscosity is decreased because of the increase of its power law index in the presence of ultrasonic oscillation. Introduction of ultrasonic oscillation into PS melt can greatly improve the processibility of PS. Their possible mechanism is also proposed in this article. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 84: 2451–2460, 2002
Synthesis of 5‐vinyl‐m‐ phenylene‐m′‐phenylene‐32‐ crown‐10 and its radical polymerization behavior
Authors: Jin Long Yi , Mah Soukil
Published: October 2004

Synthesis of a vinyl monomer, containing a 32‐membered crown ether unit (VCE) as a pendant group, was achieved by using tetra(ethylene glycol) dichloride, resorcinol, and 3,5‐dihydroxyacetophenone as starting materials. The product was identified by means of FTIR and 1H‐NMR. It was found that this monomer readily polymerizes by the conventional radical initiator 2,2′‐ azobisisobutyronitrile (AIBN) to afford a polymer whose number‐average molecular weight is 36 kg/mol; however, the final conversion of the polymer was < 80%. The results of the copolymerization of VCE with styrene (ST) or acrylonitrile (AN) are also discussed. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 84: 2372–2379, 2002
Studies on graft copolymerization of 4‐vinylpyridine onto guar gum
Authors: Taunk Kavita , Behari Kunj
Published: October 2004

Graft copolymerization of 4‐vinylpyridine (4‐VP) onto guar gum (GOH) using potassium monopersulfate (PMS)/thioacetamide (TAA) as a redox pair was studied in an aqueous medium under inert atmosphere. The concentration of potassium monopersulfate and thioacetamide should be 1.0 × 10−2 and 5.0 × 10−3 mol dm−3, respectively, for highest grafting ratio and efficiency. Efficient grafting was observed at 19.25 × 10−2 and 4.87 × 10−2 mol dm−3 concentration of 4‐vinylpyridine and sulfuric acid, respectively. The optimum temperature for grafting is 30°C. As the time period of reaction is increased, the grafting ratio increases, whereas efficiency decreases. The plausible mechanism of grafting has been suggested. A sample of guar gum and guar‐ g‐4‐vinylpyridine were subjected to thermogravimetric analysis with the objective of studying the effect of grafting 4‐vinylpyridine on the thermal stability of guar gum. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 84: 2380–2385, 2002
Viscosity of polydimethylsiloxane gum: Shear and temperature dependence from dynamic and capillary rheometry
Authors: Swallow Frank E.
Published: October 2004

The rheology of Dow Corning polydimethylsiloxane gum (PDMS/silicone gum) was studied over a time range of 10−2 to 105 s−1 and a temperature range of 23–150°C using both capillary and dynamic rheometry. A low shear Newtonian region is observed at room temperature below 0.01 rad/s (increasing to 0.1 rad/s at 150°C) for which an Arrhenius activation energy for a viscous flow of 13.3 kJ/mol was determined. The Cox–Merz rule for merging of shear and complex viscosities is found to be valid up to 10 s−1. Viscosity is found to be independent of temperature above 100 s−1, where terminal power‐law flow is encountered. This is exhibited in the dynamic data as equal plateau moduli for the various temperature curves. Gross wall slippage is seen in capillary flows above approximately 100 s−1, corresponding to a stress value of 70–100 kPa. Slip‐stick (spurt) flow is not observed. The viscosity data are best fitted by the Carreau–Yasuda model with a fitting parameter a of 0.7, a power‐law index n of 0.05 (low because of slip effect), and a zero shear viscosity of 32 kPa s at 23°C. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 84: 2533–2540, 2002
Novel biocompatible waterborne polyurethane using L‐lysine as an extender
Authors: Chen Hong , Jiang Xuwei , He Lin , Zhang Tao , Xu Min , Yu Xuehai
Published: October 2004

Polyurethane (PU) prepolymers based on isophorone diisocyanates, dimethylolpropionic acid, and polycaprolactone were prepared and chain‐ extended in water using L‐lysine (PU–L), ethylenediamine (PU–E), and their mixture (PU– L–E) as extenders, respectively. The produced emulsion exhibited satisfactory freeze/thaw stability. Films cast from emulsions exhibited excellent mechanical properties and good antiblood coagulation character. Although the water‐swelling ratio for 24 h for PU–L was higher than those of PU–L–E and PU–E, it possessed the smallest hydrolysis rate among the three samples. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 84: 2474–2480, 2002
Ability of iron(III)‐loaded carboxylated polyacrylamide‐grafted sawdust to remove phosphate ions from aqueous solution and fertilizer industry wastewater: Adsorption kinetics and isotherm studies
Authors: Unnithan Maya R. , Vinod V. P. , Anirudhan T. S.
Published: October 2004

Iron(III)‐loaded carboxylated polyacrylamide‐grafted sawdust was investigated as an adsorbent for the removal of phosphate from water and wastewater. The carboxylated polyacrylamide‐grafted sawdust was prepared by graft copolymerization of acrylamide and N,N′‐methylenebisacrylamide onto sawdust in the presence of an initiator, potassium peroxydisulfate. Iron(III) was strongly attached to the carboxylic acid moiety of the adsorbent. The adsorbent material exhibits a very high adsorption potential for phosphate ions. The coordinated unsaturated sites of the iron(III) complex of polymerized sawdust were considered to be the adsorption sites for phosphate ions, the predominating species being H2PO ions. Maximum removal of 97.6 and 90.3% with 2 g L−1 of the adsorbent was observed at pH 2.5 for an initial phosphate concentration of 100 and 250 μmol L−1, respectively. The adsorption process follows second‐order kinetics. Adsorption rate constants as a function of concentration and temperature and kinetic parameters, such as ΔG±, ΔH±, and ΔS±, were calculated to predict the nature of adsorption. The L‐type adsorption isotherm obtained in the sorbent indicated a favorable process and fitted the Langmuir equation model well. The adsorption capacity calculated by the Langmuir adsorption isotherm gave 3.03 × 10−4 mol g−1 of phosphate removal at 30°C and pH 2.5. The isosteric heat of adsorption was also determined at various surface loadings of the adsorbent. The adsorption efficiency toward phosphate removal was tested using industrial wastewater. Different reagents were tested for extracting phosphate ions from the spent adsorbent. About 98.2% of phosphate can be recovered from the adsorbent using 0.1M NaOH. Alkali regeneration was tried for several cycles with a view to recover the adsorbed phosphate and also to restore the adsorbent to its original state. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 84: 2541–2553, 2002
Spectral dispersion curves of polymeric birefringent textile fibers
Authors: Hamza A. A. , Fouda I. M. , Sokkar T. Z. N. , Sadik A. M. , El‐Bakary M. A.
Published: October 2004

Optical Fourier transform (OFT) polarizing microscopy combined with variable‐wavelength interferometry (VAWI) was used for the determination of the spectral dispersion curves of birefringent textile fibers. We observed that the maximally bright circular fringe from the OFT technique corresponded to the anticoincidence case of the fiber fringe with the empty fringe from the VAWI technique and that the maximally dark fringe from the OFT technique corresponded to the coincidence case. With this combination of the two techniques, we identified the positions of the anticoincidence and coincidence when the VAWI technique was applied to overcome the difficulties of manually determining these positions. The intensity of the OFT patterns at the center was grabbed with a charge couple device camera and analyzed with a photodiode electrical circuit. The new observation was used for the determination of the spectral dispersion curves of the birefringence of polyethylene and aramide fibers. Microinterferograms are provided as illustrations. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 84: 2481–2488, 2002
Optimization of a commercial brake pad formulation
Authors: Lu Yafei , Tang Choong‐Fong , Wright Maurice A.
Published: October 2004

A brake pad material used in a popular, commercially available vehicle that consisted of steel wool, iron powder, graphite, coke, styrene–butadiene rubber, MgO, BaSO4, and phenolic resin was tested with the friction assessment and screening test. The average friction coefficient (0.357) and total wear (19.75 wt %) were measured. An alternative friction material formulated with identical constituents but optimized with the golden section principle and relational grade analysis was produced in a laboratory environment. This material exhibited an average friction coefficient of 0.419 and a low total wear of 6.25 wt %. An analysis of component costs indicated that the large volume price of the commercial material, $1.01/kg, was less than that of the laboratory material, $1.21/kg. However, the performance/cost ratio of the new material was appreciably greater. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 84: 2498–2504, 2002
Embryology in the medical curriculum
Authors: Carlson Bruce M.
Published: October 2004

Embryology as a field is in a period of unprecedented change in its knowledge base. Similarly, this is a period of great change in medical curricular planning. One of the most significant questions in embryology education for medical students is how much of the “new” molecular embryology to mix with the “old” developmental anatomy approach. The other question is the most effective venue for instruction in medical embryology. Not all medical curricula have the same objectives; nor do they use the same educational approach. With that in mind, this review outlines several ways in which medical embryology can be offered and how it can be integrated into the medical curriculum. It also lays out topics that are worthy of inclusion in a modern embryology course or sequence. Anat Rec (New Anat) 269:89–98, 2002. © 2002 Wiley‐Liss, Inc.
Innovative testing method for an integrated radiology‐histology curriculum
Authors: Heidger Paul M. , Erkonen William , Kreiter Clarence , Pelsang Retta
Published: October 2004

A module of radiology instruction was incorporated into an existing histology course for first‐year medical students (n = 177). An innovative testing methodology for assessing the instructional effectiveness of the integrated radiology‐histology module was developed and tested. Test items were designed to measure the students' ability to integrate the two disciplines successfully. Radiologic and histologic images were displayed at each of seven stations, to which the content of the images either were or were not related. The seven stations were incorporated into three traditional histology laboratory examinations. For purposes of data analysis, each test was divided into three components, including histology alone, histology in combination, and radiology in combination. Testing lengths were equated using the Spearman‐Brown statistical adjustment. Analysis of the test results showed the reliability coefficients to be comparable to the traditional testing methods used previously in the course. Correct responses were similar in all three sections, ranging between 85 to 97%. This methodology thus appears to be an effective means of testing an integrated curriculum. Anat Rec (New Anat) 269:113–117, 2002. © 2002 Wiley‐Liss, Inc.