bluuebunny/crossref_metadata_2025 huggingface dataset:
A case of Madelung's deformity in a skeleton from Nuragic Sardinia
Authors: Canci Alessandro , Marini Elisabetta , Mulliri Giuseppina , Usai Elena , Vacca Lucia , Floris Giovanni , Borgognini Tarli Silvana M.
Published: August 2002

The case reported here refers to the skeletal remains of a mature adult male found in a collective grave known as ‘Giant's tomb’ located near Donori (Sardinia) and dating to the end of the Bronze Age. The skeleton showed bilateral shortening of the forearm associated to radial bowing, marked deformations at the radio‐ulnar distal joints and subsequent posterior dislocation of both ulnae. The whole alterations fit well with a diagnosis of Madelung's deformity, a rare form of mesomelic dysplasia. At present, this case is the most ancient evidence of Madelung's deformity. Copyright © 2002 John Wiley & Sons, Ltd.
A differential dynamic programming algorithm for differential games
Authors: Trafalis Theodore B. , Morin Thomas L.
Published: August 2002

We develop and prove the convergence of a first‐order differential dynamic programming algorithm for the solution of a zero‐sum two‐person differential game with perfect information. The algorithm extends a first‐order strong variation algorithm for optimal control given by Mayne and Polak. Assuming separability of the Hamiltonian, we decompose the differential game problem into two control subproblems, C1 and C2. The objective is to determine a point (u*, v*) in U×V, where U and V are the control spaces for C1 and C2, respectively, that satisfies an integral form of Pontryagin's maximum principle for differential games. Copyright © 2001 John Wiley & Sons, Ltd.
Moved, left no address: dam construction, displacement and issue salience
Authors: Sims Holly
Published: August 2002

Dams have displaced millions of people in many countries of the world, but such social costs of dam construction constitute a relatively new international issue. The emergence of displacement as a salient issue is explained with reference to three factors: historical circumstances, political leaders' ability to mobilize support for their priority concerns and to public participation. Participation refers to both the public's action to influence critical policy decisions and to its sense of efficacy. Cases are considered in three major dam‐building countries: the United States, India and China. In the United States, social displacement never became a public or political issue. Instead, dams have been challenged on environmental grounds. In India, by contrast, dams have stirred enormous controversy due to their social costs. The article also considers experience in China, site of the world's largest dam project, and the recent report of an international commission, the World Commission on Dams. The report's release in November 2000 marks the emergence of social displacement as a global concern. Copyright © 2001 John Wiley & Sons, Ltd.
Effect of the coupling agent's reactivity on the shrinkability of the blends consisting of grafted low‐density polyethylene and ethylene acrylic elastomer
Authors: Mishra J. K. , Roychowdhury S. , Das C. K.
Published: August 2002

Blends prepared by melt mixing of thermoplastic elastomer have gained considerable attention in recent years from a heat shrinkability point of view. Our present study deals with the measurement of heat shrinkability of the maleic anhydride grafted low‐density polyethylene and ethylene acrylic elastomer. Two samples have been prepared to study the effect of coupling agent's reactivity on the shrinkability of the blends. The coupling agents used are 4,4′‐diamino diphenyl sulphone, and 4,4′‐diamino diphenyl methane. Shrinkability was measured at room temperature, 120 °C, 150 °C, and 180 °C. Shrinkability is found to be greater in high temperature stretched sample rather than that of room temperature stretched sample. It is observed that reactivity as well as heat shrinkability is more when 4,4′‐diamino diphenyl methane is used as a coupling agent. The mechanism of interchain crosslinking reaction has been confirmed by IR spectroscopy. Differential scanning calorimetry was performed to study the thermal stability of the sample. Copyright © 2002 John Wiley & Sons, Ltd.
Synthesis of heteroarm star‐branched polymers by means of anionic living polymerization
Authors: Hirao Akira , Matsuo Akira , Morifuji Kazushi , Tokuda Yui , Hayashi Mayumi
Published: August 2002

The synthesis of well‐defined three‐ and five‐arm star polymers, with varying arm lengths, was described by the method based on anionic living polymerization. A three‐arm AB2 star polymer was synthesized by the linking reaction of a specially designed two chloromethylphenyl‐end‐functionalized polystyrene prepolymer with the anionic living polymer of t‐butyl methacrylate initiated with diphenylmethylpotassium. A five‐arm AA′2B2 star polymer was synthesized by the linking reaction of the same functionalized polystyrene having two chloromethylphenyl termini with the block copolymeric anion prepared from the coupling reaction of polystyryllithium with 1,1‐diphenylethylene‐end‐functionalized poly(α‐methylstyrene). Both star polymers were obtained in more than 95% yields and were found to possess well‐defined structures in terms of molecular weight, molecular weight distribution, arm number, and composition. Copyright © 2001 John Wiley & Sons, Ltd.
Expected, prenatally discovered, and born cases of Down syndrome in Denmark during the period 1980–1998
Authors: Olesen Larsen Severin , Hansen Jan , Nørgaard Pedersen Bent
Published: August 2002

In order to elucidate the consistency between generally used age‐dependent risk values for Down syndrome (DS) and estimates of the probability of miscarriage in Down pregnancies we have compared expected numbers with estimated numbers of births with DS in Denmark had no intervention at all been carried out. The expected numbers were calculated from the distribution of newborn children according to maternal age combined with the age‐related risk of DS. The estimated numbers of children that actually would have been born without any intervention were estimated from observed numbers of cases of DS, i.e. the cases born plus – with corrections because of the high probability of miscarriage in DS pregnancies – a proportion of those cases discovered prenatally. The analysis was carried out separately for mothers aged 35 years or older and for younger mothers. We found a high degree of compatibility between expected and estimated numbers, probably with a minor underestimation of the expected values for the older mothers. The performance of DS screening in Denmark in the period under consideration (1980–1998) is discussed in relation to the figures presented. Despite the fact that 11.8% of all pregnancies were subjected to an invasive diagnostic procedure, only about 38% of all births with DS were prevented. This means that in the period 1990–1998, reluctance to accept serological screening has indirectly resulted in the birth of almost 300 cases of DS in Denmark and at the same time the miscarriage of an unreasonable high number of normal fetuses. Copyright © 2001 John Wiley & Sons, Ltd.
The effect of fetal gender on nuchal translucency at 10–14 weeks of gestation
Authors: Lam Yung Hang , Tang Mary Hoi Yin , Lee Chin Peng , Sin Sai Yuen , Tang Rebecca , Wong Hong Soo , Wong Sai Fun
Published: August 2002

Recent data have suggested that fetal nuchal translucency (NT) is affected by fetal gender. We investigated the size of this effect in 12 189 unselected pregnancies with known normal outcomes that had undergone NT measurements between 10 and 14 weeks of gestation. NT increased with gestation and was converted to multiples of the median (MoM) for the gestational day. The median NT MoM (95% CI) for female fetuses was 0.98 (0.97–0.99). This was significantly lower than that of the male fetuses (1.03; range1.02–1.04) (p<0.0005; Wilcoxon rank‐sum test). The gender difference was not observed at 10 weeks but was observed from 11 weeks onwards. There is no obvious explanation for the above findings. Copyright © 2001 John Wiley & Sons, Ltd.
The effect of fetal gender on second‐trimester maternal serum inhibin‐A concentration
Authors: Hang Lam Yung , Hoi Yin Tang Mary
Published: August 2002

Second‐trimester serum inhibin‐A is increasingly used as a fourth marker in addition to the triple test to screen for Down syndrome. We investigated whether fetal gender had an effect on serum inhibin‐A concentration. A retrospective analysis was done on 316 normal pregnancies and 48 Down syndrome pregnancies in which maternal serum inhibin‐A assays were performed between 15 and 20 weeks of gestation and in which the fetal sex was known. The median inhibin‐A MoM (95% CI) for normal pregnancies in the presence of a male fetus was 0.93 (range 0.88–1.03). This was significantly lower than that in the presence of a female fetus (median MoM=1.04). The gender difference was not observed in the Down syndrome pregnancies. The increased inhibin‐A concentration would lead to a 2.3‐fold higher false‐positive rate in the presence of a female fetus (10.6% vs 4.6%; p<0.05, Chi‐square test). Because of the small number of cases studied, the results need to be substantiated by a larger series. If the gender effect is confirmed, adjustment for fetal sex may be necessary when inhibin‐A is used as a screening marker. Copyright © 2001 John Wiley & Sons, Ltd.
Prenatal sonographic appearance of Beare‐Stevenson cutis gyrata syndrome: two‐ and three‐dimensional ultrasonographic findings
Authors: Hsu Te‐Yao , Chang Shiuh‐Young , Wang Tu‐Jou , Ou Chia‐Yu , Chen Zen‐Huang , Hsu Pei‐Hua
Published: August 2002

Beare‐Stevenson cutis gyrata syndrome is characterized by craniofacial anomalies, particularly craniosynostosis, ear defects, cutis gyrata, acanthosis nigricans, anogenit anomalies, skin tags, and prominent umbilical stump. The prenatal two‐ and three‐dimensional ultrasonographic findings of this rare condition is reported. The detection was made at 32 weeks of gestation in a woman with polyhydramnios and fetal head anomaly. The ultrasound appearance and postnatal follow‒up are presented. Copyright © 2001 John Wiley & Sons, Ltd.
Type 2 diabetes in adolescence – unearthed at the time of registration with the general practitioner (GP)
Authors: Ng GYT , Burren CP
Published: August 2002

Type 2 diabetes, or non‐insulin‐dependent diabetes mellitus (NIDDM), is often considered to be a diagnosis of adulthood. We present a 13 year old boy who was noted to have glycosuria on routine general practitioner (GP) urine testing. Clinical examination upon referral showed massive obesity, hypertension and prominent acanthosis nigricans, and investigations confirmed hyperinsulinaemia and hyperglycaemia. Metformin and a programme of weight reduction comprise the management of this young adolescent with type 2 diabetes. Such early diagnosis should permit the institution of appropriate management to avoid the early emergence of the complications of type 2 diabetes. Copyright © 2000 John Wiley & Sons, Ltd.
Standards for professional monitoring of capillary blood glucose
Authors: Rodgers Jill , Wood J.
Published: August 2002

After updating the blood glucose meters used in Portsmouth, variations in the amount of strips used by health professionals were reported, which appeared to be unrelated to the patients' conditions. A district standard for professional monitoring of blood glucose levels was developed, following which the monitoring carried out on 100 in‐patients and 79 patients visited by community nurses was audited against the standard. Overtesting was evident in some patients in all categories, indicating inappropriate use of resources. Undertesting was also evident, which was particularly worrying in those patients who were acutely ill. The standard has been updated, and awareness about the standards has now been raised. Copyright © 2001 John Wiley & Sons, Ltd.
Baseline clinical profile and rapid progression to insulin treatment in newly diagnosed diabetic patients over 50 years of age
Authors: Kamal A.D. , Kesson C.M. , Rooney D.P.
Published: August 2002

Cardiovascular disease is very common among newly diagnosed middle aged and elderly diabetic patients and causes substantial morbidity. Most of these patients will have type 2 diabetes. However type 1 diabetes can occur at all ages and insulin treatment can be inappropriately deferred in older newly diagnosed patients. We examined the records of all new diabetic patients between 1994 and 1997, aged over 50 years and within 6 months of diagnosis, to determine their presenting cardiovascular profile and baseline factors which might predict rapid progression to insulin treatment. We identified 455 patients and 371 had 2 year follow‐up data. 71% had a blood pressure greater than 150 and/or 85 mm Hg, 70% had a cholesterol>5.0 mmol/L and 28% had diagnosed ischaemic heart disease. Within 2 years (8±2 months), 22 (6%) had progressed to insulin treatment. Predictive factors for insulin were presentation HbA1c (risk ratio 1.36, p<0.001), ketonuria (1.6, p<0.05) and the BMI/HbA1c ratio (0.23, p<0.0001) but not BMI alone. In conclusion, new diabetic patients aged over 50 years are at high cardiovascular risk. Progression to insulin treatment within 2 years of first clinic contact is uncommon. However, presenting HbA1c and especially the BMI/HbA1c ratio are strong predictors. Copyright © 2001 John Wiley & Sons, Ltd.
Recurrent hypoglycaemia in a patient with brittle diabetes
Authors: Naing K. , Wijenaike N. , Green F. , Leese G.P. , Newton R.W.
Published: August 2002

A 27‐year‐old woman with 15 years history of ‘brittle’ type 1 diabetes presented with recent history of secondary amenorrhoea and recurrent episodes of hypoglycaemia. In the past, there had been clear evidence of non‐concordance with treatment. She had had a total thyroidectomy at the age of 22 for thyrotoxicosis. Investigations confirmed Addison's disease and polyglandular autoimmune syndrome (PGA) type two.

This case demonstrates the complex interaction between medical and psychological causes for erratic glycaemic control in diabetes, even within the same patient. Copyright © 2001 John Wiley & Sons, Ltd.
Artefactually low glycated haemoglobin is a potential pitfall in diabetes management: consider congenital haemolytic anaemias
Authors: Baynes Kevin C.R. , McIntosh Colin , Feher Michael D.
Published: August 2002

Measurement of glycated haemoglobin is widely used as an index of glycaemic control in the out‐patient management of diabetes mellitus. The glycated haemoglobin measurement most commonly reported by laboratories being the HbA1c. Prospective clinical trials using the HbA1c as an index of glycaemia now indicate a benchmark for both the patient and clinician in assessing their efforts to improve glycaemic control. Glycated haemoglobins are formed by a non‐enzymatic reaction between carbohydrates and haemoglobin and a multiplicity of techniques to measure them exist. A number of conditions artefactually lower the HbA1c measurement, which may lead to false reassurance that glycaemic control is good. These conditions include iron deficiency anaemia, haemoglobinopathies, chronic renal failure or recent blood transfusion. A case of congenital haemolytic anaemia is described, highlighting another potential cause of artefactually low HbA1c. If the glycated haemoglobin result is spuriously low, other methods to assess glycaemic control, including self blood glucose monitoring and fructosamine assays, should be adopted. Copyright © 2001 John Wiley & Sons, Ltd.
Heart disease in Asian people with diabetes
Authors: Lawrence Ian G. , McNally Paul G.
Published: August 2002

Type 2 diabetes is increased up to four‐fold in middle‐aged and older Indo‐Asian people, and associated with increased coronary heart disease (CHD), and premature morbidity and mortality. Seventy‐seven percent of deaths in Indo‐Asian people with diabetes were caused by cardiovascular disease compared with 46% European deaths, in the Southall Diabetes Survey. The Indo‐Asian communities have an increased inherited lipoprotein (a) level compared to white Europeans, whilst migration results in the unmasking of a cluster of cardiovascular risk factors incorporating central obesity, hyperinsulinaemia. type‐2 diabetes and dyslipidaemia. Conventional cardiovascular risk factors are important, and in India, current smoking, hypertension and overt diabetes mellitus are the strongest predictors of a first actute myocardial infarction (AMI). Hyperlipidaemia may have a less important causal role in an Indian setting, but the situation is likely to be different in a migratory Indo‐Asian population. Unfortunately there is a lamentable lack of intervention studies in Indo‐Asian diabetic people with CHD, and currently the evidence base from other populations needs to be extrapolated. The six month mortality in Indo‐Asian people post AMI is double the white European population, despite similar use of aspirin, thrombolysis and beta blockade. and is primarily due to the increase prevalence of diabetes. This stresses the importance of active treatment of all cardiovascular risk factors, including hyperglycaemia in the peri‐infarct period. Active health promotion addressing physical activity and modifying dietaary intake is crucial in the Indo‐Asian communities, and campaigns such as Project Dil in Leicestershire have incorporated both primary and secondary prevention. The extrapolated evidence base would suggest that early use of angiotensin‐converting enzyme inhibition, statin and/or fibrate therapy, and insulin therapy may all benefit Indo‐Asian diabetic people with CHD, while metformin should be the first‐line oral hypoglycaemic agent in most Indo‐Asian diabetic people without CHD. Copyright © 2001 John Wiley & Sons, Ltd.
Hypertension in diabetes
Authors: Feher Michael D
Published: August 2002

Hypertension appears to be critically important in diabetes mellitus, not only because of its increased prevalence, but because it accelerates both macrovascular and microvascular complications of diabetes. The evidence from which current guidelines for hypertension management are derived are the recent prospective antihypertensive outcome trials which have shown significant reductions in cardiovascular endpoints, specifically in patients with diabetes. Current recommendations for the methods of blood pressure (BP) measurement have also been upon the methods used in these trials. In addition to maximal diabetic control, management of other cardiovascular risk factors, non‐drug treatments of weight loss for obesity‐related hypertension and dietary salt reduction confer benefit. Tailored therapy for the individual patient should include: the use of non‐thiazide/beta‐blocker regimens, optimal BP targets which are lower than for the individual without diabetes, adjunctive treatments (e.g. aspirin) and the need for combination drug therapies. Copyright © 2001 John Wiley & Sons, Ltd.
Familial diabetes with insulin dependency in later life involving all six members of one generation of a family
Authors: Taylor K.W. , Cassell P.G. , Hitman G.A.
Published: August 2002

Aims

The aim of this work was to study the nature of the diabetes affecting six sibs of one generation of a family.

Methods

Full clinical histories of all six members of the family were ascertained plus an assessment of beta cell reserve and insulin gene sequencing. Only one member of the family had children and these, and his grandchildren, were investigated for diabetes by glucose tolerance testing and for insulin C‐peptide and proinsulin release to detect possible abnormalities.

Results

Except in one instance, the onset of the disease was gradual and treatment was initiated with diet or oral hypoglycaemic agents. The BMI at onset of diabetes was low. Insulin treatment was required between the ages of 69 and 74. Insulin dosage was generally small and tests on some members of the family revealed residual beta cell function. No abnormalities in carbohydrate metabolism were shown in the children of one member of the family or in his grandchildren. The insulin gene investigated in two members of the family was normal. Antibodies to glutamic acid decarboxylase or tyrosine phosphatase were not detected in the propositus and her niece.

Conclusions

This case report describes familial diabetes progressing to insulin dependency in later life that affected six members of one generation of a family. It is tempting to assume that the diabetes in this family is a consequence of a shared environmental factor. However, it is equally possible that an as yet unidentified gene variant predisposing to diabetes will account for the clinical picture. Copyright © 2001 John Wiley & Sons, Ltd.
Visual outcome after laser treatment for diabetic retinopathy
Authors: Kaushal K. , New J.P. , McDowell D. , Young L.B. , Taylor R. , Young R.J.
Published: August 2002

Aims

To identify factors that predict visual outcome after laser treatment for sight threatening diabetic retinopathy (STDR) in routine care.

Patients and Methods

We studied consecutive patients from a single diabetes centre who had laser photocoagulation by a single operator (LBY) which was commenced between 1991 and 1996. Follow‐up data were obtained until the start of 1998. Potential predictors investigated were age, sex, duration and type of diabetes, HbA1C, systolic and diastolic blood pressures, lipids, initial visual acuity (VA), urine albumin/creatinine ratio (UACR), serum creatinine and presence of macrovascular disease (MVD).

Results Complete data were available for 137 (91.3%) of the 150 patients (median age 59 years, 35% female, 258 treated eyes). 140 eyes (54.3%) had maculopathy alone, 57 (22.1%) proliferative retinopathy alone and 61 (23.6%) had mixed retinopathy. Final VA (3‐48 months post photocoagulation) was better than or equal to 6/12 in 81.4% maculopathy, 82.5% proliferative and 54.1% mixed eyes. Initial VA was the strongest predictor of final VA (maculopathy r = 0.66, p = 0.01, proliferative r = 0.44, p = 0.01, mixed r = 0.30, p = 0.05). 70% of maculopathy eyes, 61.4% of proliferative eyes and 42.6% of mixed eyes were unchanged or improved. Deterioration was additionally predicted by: maculopathy – increasing age & female sex; proliferative retinopathy – high UACR & concurrent MVD; mixed disease – type 2 DM.

Conclusions

In a routine care environment laser treatment of STDR can maintain very good vision. Initiating treatment before visual acuity drops is the most important factor in preventing blindness. Copyright © 2002 John Wiley & Sons, Ltd.
Signal generation and clarification: use of case–control data
Authors: Kaufman David W. , Rosenberg Lynn , Mitchell Allen A.
Published: August 2002

Case‐control surveillance systems are useful for ‘signal’ generation, i.e., signaling potential previously unidentified adverse effects of drugs. Two systems currently in operation, the Slone Epidemiology Unit's Case‐Control Surveillance and the Birth Defects Study, have monitored drug effects since 1976. With extensive information on the diagnoses and covariates, the systems have the capacity to carry out in‐depth analyses in which the outcome measure is more specifically defined and in which confounding is controlled, thus reducing the possibility of false alarms. Copyright © 2001 John Wiley & Sons, Ltd.
Research as a visiting doctor in Afghanistan and Cambodia
Authors: Pilsczek Florian H.
Published: August 2002

This paper describes research I conducted into health care and its difficulties while working as a visiting doctor in two developing countries. The research was conducted in the Departments of Medicine, University Hospital, Jalalabad, Afghanistan, in 1994 and 1995, and Calmette Hospital, Phnom Penh, Cambodia, in 1997 and 1998. In Afghanistan I did an observational study of medical practice and case studies at the Department of Medicine, and a survey of drugs sold in pharmacies in Jalalabad. In Cambodia I surveyed hemoglobin concentrations of medical patients, and did an observational study of medical practice and case studies at Calmette Hospital. I surveyed the body weight of medical patients in relation to drug doses, and used a questionnaire to survey prescribing practices of physicians. Each project was conducted by me alone and was completed within 1–3 months. The support by the hospital was good and there where no ethics committees that had to approve the projects. Only verbal consent from the patients had to be obtained and no national laws or regulations affected the research. Small clinical research projects in developing countries are relatively easy to perform, if conducted by one researcher working in a hospital and not relying on special equipment such as a computer. Copyright © 2001 John Wiley & Sons, Ltd.
Data safety and drug safety in Germany: a closing gap?
Authors: Rathmann Wolfgang
Published: August 2002

Pharmacoepidemiology and drug utilization research are more and more involved in a fundamental conflict with data privacy regulations in Germany. In an attempt to close this gap, a working group of German data protection commissioners and representatives from epidemiologic research societies published guidelines on epidemiology and data protection, which are briefly reviewed. There are several data sources for drug utilization research and pharmacoepidemiology in Germany (national health surveys, routine data from hospitals, general practitioners, or statutory health insurance companies) allowing descriptive and analytic epidemiologic studies. Furthermore, since 1980 a random sample of all prescriptions of patients from statutory health insurances (GKV‐Arzneimittelindex) is analysed to produce an annual report on prescription drug use. More intensive use of health insurance data for evaluation of medical care including drug prescriptions is in discussion. The MediPlus (IMS HEALTH) database on 400 general and internal medicine practices provides an example to close the gap between the current demand for drug safety studies and data privacy issues. Finally, large provider systems with enormous data storage and data flow are emerging. Therefore, a further development of policies to guarantee ethically correct use of personally identifiable health data in the changing health care environment is urgently required. Copyright © 2001 John Wiley & Sons, Ltd.
Thermally crosslinked polymer blends of polyurethane and chlorobutyl elastomers (sulfur cure)
Authors: Khatua B B , Das C K
Published: August 2002

Blends of polyurethane with chlorobutyl elastomer prepared by three different blending techniques have been studied in the entire composition range. The properties of the blends showed that the blending technique plays an important role in determining the blend properties. IR spectral analysis revealed that interchain crosslinking is possible in this blend system upon heat treatment. Thermal stability of blends prepared by preheating the preblend was increased and the degradation process was retarded. Extractability of the single phase, by solvent, was also limited significantly in the case of the preheated preblended sample, probably due to phase adhesion.

© 2001 Society of Chemical Industry
Kinetics and reaction mechanism of template polymerization investigated by conductimetric measurements Part 4. Radical polymerization of acrylic acid in the presence of poly(vinyl alcohol): characterization of resulting polymer blends
Authors: Ciardelli Gianluca , Barbani Niccoletta , Rainaldi Iacopo , Giusti Paolo , Cristallini Caterina
Published: August 2002

The radical polymerization of acrylic acid in the presence of poly(vinyl alcohol) as a template in aqueous solution has been studied using conductimetry, which shows template influences on the reaction rate. A comparison is made between data obtained by differential scanning calorimetry and infrared spectroscopy for poly(acrylic acid)–poly(vinyl alcohol) blends prepared either by template polymerization or by casting of the preformed polymers. Evidence for more significant interpolymer interactions in blends prepared by template polymerization than in those obtained by simple mixing is given.

© 2001 Society of Chemical Industry
Homogeneous complex solution formed through interactions of poly(acrylamide‐co‐acrylic acid)/poly(acrylamide‐co‐dimethyldiallylammonium chloride) complex with Mn+ hydration metal ions in aqueous media
Authors: Dan Yi , Wang Qi
Published: August 2002

A homogeneous complex solution, formed through inter‐polyelectrolyte complexation of poly(acrylamide‐co‐acrylic acid) (P(AM‐AA)) with poly(acrylamide‐co‐dimethyldiallylammonium chloride) (P(AM‐DMDAAC)) and interaction of the P(AM‐AA)/P(AM‐DMDAAC) complex with M
n+ hydrated metal ion, was prepared and the structure and properties of the P(AM‐AA)/P(AM‐DMDAAC)/M
n+ homogeneous complex solution were studied by UV spectrometry, dynamic light scattering and viscometry. The experimental results show that the homogeneous complex solution can be obtained by controlling the composition of the P(AM‐AA)/P(AM‐DMDAAC) complex and the M
n+ metal ion content. Compared to the constituents, ie the P(AM‐AA) solution, the P(AM‐DMDAAC) solution and the P(AM‐AA)/P(AM‐DMDAAC) complex solution, the P(AM‐AA)/P(AM‐DMDAAC)/M
n+ complex solution has a new peak at 270 nm in its UV spectrum, a larger hydrodynamic radius, and hence a higher solution viscosity, all of which indicate that there exist specific interactions between polymers and M
n+ metal ions. These interactions lead to the formation of a network structure and hence an obvious increase not only in solution viscosity but also in resistance of the polymer solution to simple salts, to temperature changes and to shearing.

© 2001 Society of Chemical Industry
Synthesis and characterization of functionalized thermoplastics as reactive modifiers for bismaleimide resins
Authors: Hamerton Ian , Klewpatinond Paul
Published: August 2002

The preparation and characterization of a series of chemically functionalized oligosulphones (of approximate
M
n 5000–17 000 g mol−1) bearing propenyl groups substituted into the main aromatic backbone is reported. The thermal characterization of the oligomers using differential scanning calorimetry was carried out and the main features of the thermally‐initiated process are presented. Blends of the oligomers were formed with a commercial bismaleimide and their thermal characteristics are also discussed.

© 2001 Society of Chemical Industry
Polymer–polymer interaction, in the presence of a solvent as measured by viscometry
Authors: Gómez Clara M , Porcar Iolanda , Recalde Ileana , Campos Agustín
Published: August 2002

Dilute solution viscometry experiments have been carried out in five ternary polymer systems solvent(1)/polymer(2)/polymer(3). Values of the specific viscosity of polymer (3) in a ‘binary solvent’ formed by polymer(2) + solvent(1) have been used to determine the compatibility of the polymer blends. Krigbaum and Wall formalism has been used to predict compatibility which relies on an interaction parameter $b_{23}^{(1)}$ that depends on the concentration, weight fraction and molar mass of each polymer. To reduce the dependences and to clarify the criterion of compatibility, a parameter $b_{23}^{(2)}$ independent of polymer (3) composition and molar mass has been deduced. This parameter shows the same behaviour with polymer(2) concentration as the Stockmayer–Fixman parameter B.

© 2001 Society of Chemical Industry
Optical study of perylene dye doped poly(methyl methacrylate) as fluorescent solar collector
Authors: Mansour A F , El‐Shaarawy M G , El‐Bashir S M , El‐Mansy M K , Hammam M
Published: August 2002

The optical absorption of poly(methyl methacrylate) (PMMA), doped with perylene dye, prepared by both thermal polymerization and casting methods, has been measured before and after exposure to filtered or unfiltered light using xenon arc lamp or day light. The optical band gap of thermally polymerized PMMA was reduced by doping with perylene dye or exposure to UV radiation. Study of DSC and FTIR measurements confirmed that the samples prepared by thermal polymerization are more stable than solvent‐cast samples.

© 2002 Society of Chemical Industry
Synthesis and characterization of sulfonated liquid crystalline polyesters
Authors: Lin Qin , Pasatta Jeremy , Wang Zhen‐He , Ratta Varun , Wilkes Garth L , Long Timothy E
Published: August 2002

Liquid crystalline polyesters based on hexanediol, dimethyl 4,4′‐biphenyldicarboxylate, and various levels of dimethyl 5‐sodiosulfoisophthalate (0–20 mol%) were prepared using a conventional melt polymerization process. The presence and quantification of the ionic functionality was surveyed using 1H NMR spectroscopy. Solution viscosities and corresponding molecular weights decreased when the ionic monomer concentration exceeded a critical value (higher than 3 mol%). Differential scanning calorimetry indicated a maximum in the isotropic transition temperature versus ionic modification at approximately 10 mol%. Dynamic mechanical analysis indicated that the glass transition temperature was suppressed due to ionic association at high concentrations (greater than 3 mol%) of ionic functionality. Polarized light microscopy and wide‐angle X‐ray diffraction were used to identify the smectic liquid crystalline and crystalline phases.

© 2002 Society of Chemical Industry
Synthesis of phosphonated styrenic copolymers and their chemical modifications
Authors: Boutevin Bernard , Hervaud Yves , Boulahna Ahmed , Hadrami El Mestafa El
Published: August 2002

We report, for the first time, the synthesis of a phosphonated styrenic monomer dimethyl vinylbenzyl phosphonate (VBP) according to the methods described in the literature for its equivalent diethyl vinylbenzyl phosphonate, and also the monodealkylation of this monomer (VBP) to the monosalt in a neutral medium and to the corresponding monoacid via a sulfonic resin. Various statistical copolymers and statistical block copolymers of styrene and VBP were prepared with different molar percentages of these comonomers. The dealkylation of statistical copolymers was carried out in the same way as for VBP. The phosphonated statistical copolymers, prepared, were characterized by various analytical methods which show good agreement with their structures.

© 2002 Society of Chemical Industry
Case study of childhood disintegrative disorder— Heller's syndrome
Authors: Bray Melissa A. , Kehle Thomas J. , Theodore Lea A. , Broudy Matthew S.
Published: August 2002

The case of a 25‐year‐old male with childhood disintegrative disorder (CDD), or Heller's syndrome, is discussed in terms of differential diagnosis, progression of the disorder, and suggestions for home‐ and school‐based interventions. The case documents the progressive deterioration of cognitive and social competencies. Given the paucity of research and information with respect to CDD, further clinical investigation is suggested. © 2002 John Wiley & Sons, Inc.
The role of aggression and social competence in children's perceptions of the child–teacher relationship
Authors: Blankemeyer Maureen , Flannery Daniel J. , Vazsonyi Alexander T.
Published: August 2002

The role of children's aggression and three indices of social competence (peer‐preferred behavior, teacher‐preferred behavior, and school adjustment) in children's perceived relationships with their teachers was assessed. Participants were 1,432 third through fifth graders (688 males, 744 females) and their teachers. The results from hierarchical regression analyses showed statistically significant interaction effects. Poor school adjustment was associated with more negatively perceived child teacher relationships for boys than for girls. In addition, the perceived child–teacher relationship among aggressive children was more favorable among those with high levels of school adjustment than among those who were poorly adjusted at school. Implications for school psychologists and teachers are discussed. © 2002 John Wiley & Sons, Inc.
A national survey of current supervision and evaluation practices of school psychologists
Authors: Chafouleas Sandra M. , Clonan Sheila M. , Vanauken Tracy L.
Published: August 2002

This paper presents findings from a national survey of school psychologists regarding current supervision and evaluation practices. Thirty‐seven percent of usable surveys were returned. Overall results suggested that the sample of school psychologists were somewhat to moderately satisfied with current supervision and evaluation practices. However, wide variation in how supervision, evaluation, and professional development are obtained was indicated. The evaluation process is most often conducted by an administrator who may not be familiar with school psychology; and it is not viewed as an opportunity for professional development. In addition, evaluation criteria often are not tailored specifically to the roles of the school psychologist. Most alarming, and consistent with previous research, is that many school psychologists do not have enough supervision available to meet either their wishes or standards for the profession. Higher satisfaction with supervision was found when participants were provided with more regular and formal supervision contacts. Participants also indicated a person knowledgeable about school psychology could best provide supervision. Implications of the results and future directions are discussed. © 2002 Wiley Periodicals, Inc.
Assessment of violence potential among school children: Beyond profiling
Authors: Burns Matthew K. , Dean Vincent J. , Jacob‐Timm Susan
Published: August 2002

The increasing level of public attention to violence in American schools makes the issue a top priority among educators. School psychologists could play an important role in identifying at‐risk youth, and planning appropriate individual, school, and community interventions related to school violence. However, there is limited literature examining different assessment approaches that could be used to evaluate student risk for violence. This article reviews (a) characteristics of students “at risk” for violence, (b) informal checklists and matching student characteristics to profiles of typical violent students and (c) threat assessment based on Borum et al.'s (1999) model. Ethical and legal considerations are covered as well. © 2001 John Wiley & Sons. Inc.
Revision of the structure and stereochemistry of the 2‐naphthol–acetaldehyde 2:2 condensation product. A study by X‐ray crystallography and the AM1 method
Authors: Rashidi‐Ranjbar Parviz , Mohajeri Ali , Hossein Mahmoudkhani Amir
Published: August 2002

The structure of the 2:2 condensation product of 2‐naphthol and acetaldehyde, 1‐(1‐methyl‐2,3‐dihydro‐1H‐benzo[ f ]chromen‐3‐yl)‐2‐naphthol, revised by X‐ray crystallography, is presented. A moderate intramolecular hydrogen bond is found between the phenolic OH and chromene oxygen atom both in the solid state and in solution. In the crystal structure, the naphthyl groups are oriented in parallel with a π–π stacking distance of 354 pm. AM1 studies are used to explain the formation of one of the four possible stereoisomers for the title compound. Comparison of the experimental and calculated coupling constants indicates that the molecule adopts exclusively the solid‐state structure in solution. Copyright © 2001 John Wiley & Sons, Ltd.
Ab initio study of the structures of CH3NH3+ and CH3PH3+ in aqueous solution
Authors: Masamura M
Published: August 2002

The purpose of this work was to determine quantitatively the structures of CH3NH3+ and CH3PH3+ in aqueous solution. For this purpose, the structures of CH3NH3+ (H2O)
n were optimized using MP2/6–31G(d) (n = 0, 1, 2, 3, 4, 5, 6) and RHF/4–31G (n = 0, 1, 2, 3, 4, 5, 6, 9, 21) and the structures of CH3PH3+ (H2O)
n (n = 0, 1, 2, 3) were optimized using MP2/6–31+G(d,p). Based on these structures, the structure of CH3NH3+ in aqueous solution was predicted as follows: C—N = 1.479 Å, N—H = 1.047 Å, C—H = 1.088 Å, NCH = 108.9° and CNH = 108.5°. The C—N bond length of CH3NH3+ in aqueous solution is predicted to be smaller than that in the gas phase by 0.03 Å. The N—H bond lengths of CH3NH3+ in aqueous solution are predicted to be longer than those in the gas phase by 0.02 Å. The structure of CH3PH3+ in aqueous solution was predicted as follows: C—P = 1.808 Å, P—H = 1.394 Å, C—H = 1.087 Å, PCH = 109.5° and CPH = 109.9°. The structure of CH3PH3+ in aqueous solution is predicted to be similar to that in the gas phase. Copyright © 2001 John Wiley & Sons, Ltd.
Substituent effect on the cationic ring‐opening polymerization of acyloxymethyl five‐member cyclic dithiocarbonates
Authors: Steblyanko Alexander , Choi Wonmun , Sanda Fumio , Endo Takeshi
Published: August 2002

Five‐member cyclic dithiocarbonates were synthesized by the reactions of carbon disulfide with benzoic, p‐anisic, p‐chlorobenzoic, 1‐naphthalenecarboxylic, p‐nitrobenzoic, and p‐(tert‐butyl)benzoic glycidyl esters, and their cationic ring‐opening polymerizations were carried out with methyl trifluoromethane sulfonate and trifluoromethane sulfonic acid as initiators at room temperature to 80 °C. Polymers with number‐average molecular weights of 3400–24,900 were obtained in high yields, and their structures were estimated by NMR and IR spectroscopy. The monomers showed a clear difference in the polymerization rate according to the substituents. The rate of polymerization decreased in the order of p‐chlorobenzoic ≥ benzoic > 1‐naphthalenecarboxylic > p‐nitro‐benzoic > p‐tert‐butylbenzoic > p‐anisic. The data of the reaction kinetics, NMR studies, and molecular orbital calculations proved a plausible mechanism involving the participation of p‐substituted benzoyloxymethyl groups to stabilize the cationic propagating end. The polymers showed decomposition temperatures with 5% weight loss ranging from 200 to 260 °C. No glass‐transition temperatures for the polymers were observed below 200 °C by differential scanning calorimetry. © 2001 John Wiley & Sons, Inc. J Polym Sci Part A: Polym Chem 39: 3967–3980, 2001
Photosensitive, self‐assembled ultrathin films based on diazoresin and phosphate‐containing polyanions
Authors: Li Qi , Ouyang Jianhua , Chen Jinyu , Zhao Xinsheng , Cao Weixiao
Published: August 2002

Photosensitive ultrathin films with phosphate‐containing polyanions and diazoresin (DR) as a polycation were fabricated with a self‐assembly technique. The phosphate‐containing polyanions were poly(sodium phosphate), phosphorylated poly(vinyl alcohol), and DNA. The fabrication process was monitored by the determination of the absorbance from DR. The surface morphology of the multilayer films was observed with atomic force microscopy. Under ultraviolet irradiation, the linkage between the layers of the films changed from being ionic to being covalent; as a result, the stability of the films toward polar solvents increased. This kind of film may have applications for biosensor devices. © 2001 John Wiley & Sons, Inc. J Polym Sci Part A: Polym Chem 40: 222–228, 2002
New positive‐type photosensitive polymer based on poly(2,6‐dihydroxy‐1,5‐naphthylene) and diazonaphthoquinone
Authors: Sasada Yasuyuki , Shibasaki Yuji , Suzuki Masato , Ueda Mitsuru
Published: August 2002

A positive working photosensitive polymer based on poly(2,6‐dihydroxy‐1,5‐naphthylene) (PDHN) with 1‐(1,1‐bis{4‐[2‐diazo‐1(2H)naphthalene‐5‐sulfonyloxy]phenyl}ethyl)‐4‐(1‐{4‐[2‐diazo‐1(2H)naphthalene‐5‐sulfonyloxy]phenyl}methylethyl) benzene (S‐DNQ) as a photosensitive compound has been developed. PDHN (number‐average molecular weight: 13,000; polydispersity index: 1.9) was prepared by oxidative coupling polymerization of the 2,6‐dihydroxynaphthalene‐benzylamine complex using iron(III) chloride hexahydrate in the solid state. A 10 wt % loss temperature of PDHN was 450 °C in air, and the film of 1 μm thickness showed excellent transparency above 400 nm. The resist system consisting of PDHN and S‐DNQ gave a clear positive pattern when it was exposed to 436 nm of light, followed by development with a 0.50 wt % aqueous tetramethylammonium hydroxide solution at 25 °C. The sensitivity (D) and contrast (γ) were 300 mJ/cm2 and 2.1, respectively. © 2001 John Wiley & Sons, Inc. J Polym Sci Part A: Polym Chem 40: 393–398, 2002
Preparation and emission properties of various poly(dimethylsilylenearylenevinylene)s: Effects of geometric structures and π units on their emission properties
Authors: Kwak Giseop , Masuda Toshio
Published: August 2002

trans‐Poly(dimethylsilylenearylenevinylene)s (trans‐rich) and cis‐poly(dimethylsilylenearylenevinylene)s (cis‐rich) containing phenylene, biphenylene, and phenylenesilylenephenylene units were prepared by hydrosilylation catalyzed with the RhI(PPh3)3 complex. The addition of a phenylene π unit to poly(silylenephenylenevinylene) expanded the conjugation in the main chain, whereas the insertion of a dimethylsilylene σ unit in the biphenylene moiety reduced the conjugation. UV spectra of the trans‐type polymers showed redshifts and hyperchromic effects with respect to those of the cis‐type polymers, indicating wider conjugation, and the quantum yields of emission of the former polymers were much higher than those of the latter polymers. The quantum yield of the trans‐rich polymer with the biphenylene moiety reached 0.15, which was about 102 times as large as those of trans‐type polymers with phenylene (3.4 × 10−3) and phenylenesilylenephenylene (1.9 × 10−3) moieties. The effects of the geometric structure and π unit on the absorption and emission properties of these polymers were examined with molecular orbital methods. © 2002 John Wiley & Sons, Inc. J Polym Sci Part A: Polym Chem 40: 535–543, 2002; DOI 10.1002/pola.10139
Synthesis of amphiphilic block–graft copolymers [poly(styrene‐b‐ethylene‐co‐butylene‐b‐styrene)‐g‐poly(acrylic acid)] and their aggregation in water
Authors: Ning Fanglin , Jiang Ming , Mu Minfang , Duan Hongwei , Xie Jingwei
Published: August 2002

Novel block–graft copolymers [poly(styrene‐b‐ethylene‐co‐butylene‐b‐styrene)‐g‐poly(tert‐butyl acrylate)] were synthesized by the atom transfer radical polymerization (ATRP) of tert‐butyl acrylate (tBA) with chloromethylated poly(styrene‐b‐ethylene‐co‐butylene‐b‐styrene) (SEBS) as a macromolecular initiator. The copolymers were composed of triblock SEBS as the backbone and tBA as grafts attached to the polystyrene end blocks. The macromolecular initiator (chloromethylated SEBS) was prepared by successive hydrogenation and chloromethylation of SEBS. The degree of chloromethylation, ranging from 1.6 to 36.5 mol % according to the styrene units in SEBS, was attained with adjustments in the amount of SnCl4 and the reaction time with a slight effect on the monodispersity of the starting material (SEBS). The ATRP mechanism of the copolymerization was supported by the kinetic data and the linear increase in the molecular weights of the products with conversion. The graft density was controlled with changes in the functionality of the chloromethylated SEBS. The average length of the graft chain, ranging from a few repeat units to about two hundred, was adjusted with changes in the reaction time and alterations in the initiator/catalyst/ligand molar ratio. Incomplete initiation was detected at a low conversion; moreover, for initiators with low functionality, sluggish initiation was overcome with suitable reaction conditions. The block–graft copolymers were hydrolyzed into amphiphilic ones containing poly(acrylic acid) grafts. The aggregation behavior of the amphiphilic copolymers was studied with dynamic light scattering and transmission electron microscopy, and the aggregates showed a variety of morphologies. © 2002 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 40: 1253–1266, 2002