bluuebunny/crossref_metadata_2025_split huggingface dataset:
Elementary mechanisms of metallocene activation by methylaluminoxane cocatalysts for olefin polymerization
Authors: Pédeutour Jean‐Noël , Radhakrishnan Karunakaran , Cramail Henri , Deffieux Alain 
Published: October 2002

AbstractThe different elementary steps in the activation process of racEt(Ind)2ZrCl2 by commercial methylaluminoxane (MAO) have been studied by UV/visible spectroscopy and correlated with hexene polymerization kinetics. After monomethylation of the zirconocene dichloride (λ = 396 nm), abstraction of Cl ligand by MAO at low Al/Zr ratios (Al/Zr = 150) yields tight ion pairs, with an absorption band centred at λ = 440 nm, which are inactive towards hexene polymerization. Addition of MAO in large excess (Al/Zr = 2000) is required to form the active species. The latter, characterized by an absorption at λ = 470 nm, were identified as trimethylaluminium (TMA) separated ion pairs. The activation by commercial MAO of racEt(Ind)2ZrX2, with X being methyl, benzyl or dimethylamino as extractable group, instead of chloride, reveals much easier and complete activation at low Al/Zr ratios (Al:Zr = 50–150). For these systems, formation of active ion pairs of different catalytic activities and absorbing in the range λ = 430–440 nm is observed. The use of TMA‐depleted MAO instead of commercial MAO, as cocacalyst for racEt(Ind)2ZrCl2 actvation also allows the formation of active tight ion pairs absorbing at λ = 440 nm at low Al/Zr ratio. These results underline the negative role of chloride ligands when associated with TMA (contained in MAO) in the activation process of zirconocene for olefin polymerization, and also suggest interesting alternatives to reduce the amount of MAO necessary for metallocene activation.© 2002 Society of Chemical Industry
Antitubercular constituents from the hexane fraction of Morinda citrifolia Linn. (Rubiaceae)
Authors: Saludes Jonel P. , Garson Mary J. , Franzblau Scott G. , Aguinaldo Alicia M. 
Published: October 2002

AbstractA crude ethanol extract and hexane fraction from Morinda citrifolia Linn. (Rubiaceae) show antitubercular activity. The major constituents of the hexane fraction are E‐phytol, cycloartenol, stigmasterol, β‐sitosterol, campesta‐5,7,22‐trien‐3β‐ol and the ketosteroids stigmasta‐4‐en‐3‐one and stigmasta‐4‐22‐dien‐3‐one. E‐Phytol, a mixture of the two ketosteroids, and the epidioxysterol derived from campesta‐5,7,22‐trien‐3β‐ol all show pronounced antitubercular activity. Copyright © 2002 John Wiley & Sons, Ltd.
Antimicrobial potential of two different Hypericum species available in India
Authors: Mukherjee Pulok K. , Saritha G. S. , Suresh B. 
Published: October 2002

AbstractThe antimicrobial activity of extracts of the leaves and stems of two different varieties of Hypericum was evaluated by the disc diffusion method. Petroleum ether, acetone, chloroform and methanol extracts of Hypericum mysorense and Hypericum patulum stems and leaves were investigated for their antimicrobial activity against six different strains of bacteria and fungi by the zone of inhibition method (ZIM). The results showed that both the stem and leaf extracts of both species have a very broad spectrum of antibacterial activity. The petroleum ether and acetone extract of the leaves and stems of H. mysorense did not show antifungal effects against any of the six fungal organisms tested but other extracts showed a potential antifungal effect which was comparable to that of griseofulvin, the standard antifungal agent. Thus these results demonstrate that the leaf and stem extracts of both the Hypericum species have a very broad spectrum of activity and suggest that they may be useful in the treatment of various microbial infections. Copyright © 2002 John Wiley & Sons, Ltd.
Anti‐stress and anti‐fatigue effect of fermented rice bran
Authors: Kim K. M. , Yu K. W. , Kang D. H. , Suh H. J. 
Published: October 2002

AbstractThe anti‐stress and anti‐fatigue effects of a hot water extract of fermented rice bran (FRB) were investigated with Saccharomyces cerevisae IFO 2346 on rats or mice. Oral administration (1 g/kg/day) of a hot water extract of FRB inhibited major changes in weight of the adrenal, thymus, spleen and thyroid, showing the anti‐stress effect. A hot water extract of FRB also inhibited the increase of GPT and LDH activity, cholesterol and serum glucose levels. Administration (1 g/kg/day) for 2 weeks significantly prolonged the swimming time, resulting in an increase of the anti‐fatigue effect. From these results, it can be considered that FRB has an anti‐stress and anti‐fatigue effect. Copyright © 2002 John Wiley & Sons, Ltd.
Antistress effects of bacosides of Bacopa monnieri: modulation of Hsp70 expression, superoxide dismutase and cytochrome P450 activity in rat brain
Authors: Chowdhuri D. Kar , Parmar D. , Kakkar P. , Shukla R. , Seth P. K. , Srimal R. C. 
Published: October 2002

AbstractThe antistress effect of bacosides of Brahmi (Bacopa monnieri, BBM), dissolved in distilled water, was ­studied in adult male Sprague Dawley rats by administering oral doses of 20 and 40 mg/kg for 7 consecutive days. In half of the animals treated with 20 or 40 mg/kg of BBM, stress was given 2 h after the last dose. Stress was also administered to the animals treated with distilled water alone. BBM, at both doses, did not induce a significant change in the expression of Hsp70 in any brain region studied while stress alone produced a significant increase in the Hsp70 expression in all the brain regions. A significant decrease in the activity of superoxide dismutase (SOD) was evident in the hippocampus with the lower dose of BBM and in animals given stress alone, while an increase in the activity of SOD was observed in the brain regions with the higher dose of BBM. An increase in the activity of cytochrome P450 (P450) dependent 7‐pentoxyresorufin‐o‐dealkylase (PROD) and 7‐ethoxyresorufin‐o‐deethylase (EROD) was observed in all the brain regions after exposure to stress alone and with both doses of BBM although the magnitude of induction of P450 expression was less with a higher dose of BBM. Interestingly, stress when given to the animals pretreated with BBM for 7 days resulted in a decrease in Hsp70 expression in all the brain regions with a significant decrease occurring only in the hippocampus. Likewise the activity of SOD was found to be further reduced in all the brain regions in the animals treated with the lower dose of BBM followed by stress. However, when stress was given to the animals pretreated with the higher dose of BBM, a significant increase in the enzyme activity was observed in the cerebral cortex and in the rest of the brain while the activity of SOD was reduced to a much greater extent in the cerebellum and in the hippocampus. Likewise, the activity of P450 enzymes was found to be restored to almost control levels in the animals given stress and pretreated with the higher dose of BBM, while a lesser degree of induction, compared with animals treated with BBM or stress alone, was observed in the animals pretreated with the lower dose of BBM and given stress. The data indicate that BBM has potential to modulate the activities of Hsp70, P450 and SOD thereby possibly allowing the brain to be prepared to act under adverse conditions such as stress. Copyright © 2002 John Wiley & Sons, Ltd.
Hypoglycaemic activity of Scopariadulcis L. extract in alloxan induced hyperglycaemic rats
Authors: Pari L. , Venkateswaran S. 
Published: October 2002

AbstractScoparia dulcis L. commonly known as ‘Sweet Broomweed’ is widely used in Indian folk medicine for the treatment of diabetes mellitus. Oral administration of 0.15, 0.30 and 0.45 g/kg body weight of the aqueous extract of the Scoparia dulcis leaves (SLEt) for 45 days resulted in a significant reduction in blood glucose, glycosylated haemoglobin and an increase in total haemoglobin but in the case of 0.45 g/kg body weight the effect was highly significant. The aqueous extract also prevented a decrease in the body weight. An oral glucose tolerance test was also performed in experimental diabetic rats, in which there was a significant improvement in glucose tolerance in animals treated with SLEt and the effect was comparable to that of glibenclamide. Copyright © 2002 John Wiley & Sons, Ltd.
Relaxant activity of raspberry ( Rubus idaeus) leaf extract in guinea‐pig ileum in vitro
Authors: Rojas‐Vera Janne , Patel Asmita V. , Dacke Christopher G. 
Published: October 2002

AbstractTea made from the leaves of Rubus idaeus L. (raspberry) has been used for centuries as a folk medicine to treat wounds, diarrhoea, colic pain and as a uterine relaxant. Extracts of dried raspberry leaves prepared with different solvents, (n‐hexane, ethyl acetate, chloroform and methanol) were tested in vitro for relaxant activity on transmurally stimulated guinea‐pig ileum. The methanol (MeOH) extract exhibited the largest response and also indicated that the active compounds are of a relatively polar nature. Hence the bulk of the leaves were extracted with methanol and the dried extract fractionated on a silica gel column, eluting with chloroform, mixtures of chloroform and methanol and finally methanol. Each fraction was examined by thin layer chromatography and tested for relaxant activity in an in vitro transmurally stimulated guinea‐pig ileum preparation. The fractions eluted with chloroform (CHCl3) lacked relaxant activity. Samples eluted with CHCl3/MeOH (95:5) had moderate relaxant activity, while a second distinctive peak of activity eluted with a more polar solvent mixture (CHCl3/MeOH 50:50) provided strong dose dependent responses. Evidence was obtained that there are at least two components of raspberry leaf extract which exhibit relaxant activity in an in vitro gastrointestinal preparation. Copyright © 2002 John Wiley & Sons, Ltd.
Onions—A global benefit to health
Authors: Griffiths Gareth , Trueman Laurence , Crowther Timothy , Thomas Brian , Smith Brian 
Published: October 2002

AbstractOnion (Allium cepa L.) is botanically included in the Liliaceae and species are found across a wide range of latitudes and altitudes in Europe, Asia, N. America and Africa. World onion production has increased by at least 25% over the past 10 years with current production being around 44 million tonnes making it the second most important horticultural crop after tomatoes. Because of their storage characteristics and durability for shipping, onions have always been traded more widely than most vegetables. Onions are versatile and are often used as an ingredient in many dishes and are accepted by almost all traditions and cultures. Onion consumption is increasing significantly, particularly in the USA and this is partly because of heavy promotion that links flavour and health. Onions are rich in two chemical groups that have perceived benefits to human health. These are the flavonoids and the alk(en)yl cysteine sulphoxides (ACSOs). Two flavonoid subgroups are found in onion, the anthocyanins, which impart a red/purple colour to some varieties and flavanols such as quercetin and its derivatives responsible for the yellow and brown skins of many other varieties. The ACSOs are the flavour precursors, which, when cleaved by the enzyme alliinase, generate the characteristic odour and taste of onion. The downstream products are a complex mixture of compounds which include thiosulphinates, thiosulphonates, mono‐, di‐ and tri‐sulphides. Compounds from onion have been reported to have a range of health benefits which include anticarcinogenic properties, antiplatelet activity, antithrombotic activity, antiasthmatic and antibiotic effects. Here we review the agronomy of the onion crop, the biochemistry of the health compounds and report on recent clinical data obtained using extracts from this species. Where appropriate we have compared the data with that obtained from garlic (Allium sativum L.) for which more information is widely available. Copyright © 2002 John Wiley & Sons, Ltd.
Anxiolytic and antiemetic activity of Zingiber officinale
Authors: Vishwakarma S. L. , Pal S. C. , Kasture Veena S. , Kasture S. B. 
Published: October 2002

AbstractThe benzene fraction (BF) of a petroleum ether extract of dried rhizomes of ginger, which contained anticonvulsant principle(s), was screened for anxiolytic and antiemetic activity. Motor coordination was not affected by BF per se, but diazepam‐induced motor incoordination was potentiated. Animals treated with BF showed decreased occupancy in the closed arm of the elevated plus maze suggesting the presence of anxiolytic principles in the BF. BF also blocked lithium sulphate‐induced conditioned place aversion indicating antiemetic activity. These findings suggest that the fraction (BF) possesses anticonvulsant, anxiolytic and antiemetic activity. Copyright © 2002 John Wiley & Sons, Ltd.
Effects of black radish root (Raphanus sativus L. var niger) on the colon mucosa in rats fed a fat rich diet
Authors: Sipos P , Hagymási K , Lugasi A , Fehér E , Blázovics A 
Published: October 2002

AbstractThe effect of black radish root (Raphanus sativus L. var niger) was studied on the structure and redox state of the colon mucosa in fat‐rich diet fed rats. The epithelial lining disrupted, the number of enterocytes and the goblet cells reduced and inflammatory cells were observed in rats fed with a fat‐rich diet. After treatment with granules from black radish root all of the histopathological changes and parameters of the redox state caused by the fat‐rich diet were improved. The structure of the epithelial cells was similar to the controls, the number of goblet cells increased and no inflammation was observed. Copyright © 2002 John Wiley & Sons, Ltd.
Potential roles of cellular proteins in HIV‐1
Authors: Ott David E. 
Published: October 2002

AbstractHuman immunodeficiency virus type‐1 particles contain host proteins, both on their surface and interior. This review summarises the cellular proteins found in these virions and covers some of their potential roles in the viral life cycle and pathogenesis. For most proteins studied, their role and function are either unknown or in the hypothesis stage. This reflects the relatively recent emphasis given to these proteins by the HIV‐1 field as well as the incomplete understanding of their function in the cell. The study of cellular proteins in HIV‐1 promises to help us better understand the interaction of this virus with the cell, the immune system, and the whole human host as well as to shed light on the nature of AIDS and suggest more targets for therapeutic intervention. Finally, many of the cell systems themselves are still poorly understood. The extensive study of HIV‐1 has already brought increased attention to the fields of immunology and vaccine science and, in the same way, might assist our understanding of the cellular pathways themselves. Published in 2002 by John Wiley & Sons, Ltd.
Environment, economy and society: fitting them together into sustainable development
Authors: Giddings Bob , Hopwood Bill , O'Brien Geoff 
Published: October 2002

AbstractSustainable development is a contested concept, with theories shaped by people's and organizations' different worldviews, which in turn influence how issues are formulated and actions proposed. It is usually presented as the intersection between environment, society and economy, which are conceived of as separate although connected entities. We would argue that these are not unified entities: rather they are fractured and multi‐layered and can be considered at different spatial levels. The economy is often given priority in policies and the environment is viewed as apart from humans. They are interconnected, with the economy dependent on society and the environment while human existence and society are dependent on, and within the environment. The separation of environment, society and economy often leads to a narrow techno‐scientific approach, while issues to do with society that are most likely to challenge the present socio‐economic structure are often marginalized, in particular the sustainability of communities and the maintenance of cultural diversity. Copyright © 2002 John Wiley & Sons, Ltd. and ERP Environment
Separation of concerns for software evolution
Authors: Mens Tom , Wermelinger Michel 
Published: October 2002

AbstractThis special issue reports on approaches that apply the idea of separation of concerns to software evolution. In this context, separation of concerns allows us to separate parts of the software that exhibit different rates of change or different types of change. This makes it possible to provide better evolution support for those parts that have a higher change rate, or to provide different evolution techniques for different views on the software. Another common way to achieve separation of concerns is by raising the level of abstraction to the level of software architectures, business rules and metamodels. This makes software evolution more manageable. The above ideas emerged as important conclusions of the workshop on Formal Foundations of Software Evolution, which was co‐located with the Conference on Software Maintenance and Re‐engineering in Lisbon in March 2001. Of the 12 original position papers, five have been selected for revision and inclusion in this special issue of the Journal of Software Maintenance and Evolution. Copyright © 2002 John Wiley & Sons, Ltd.
Change impact analysis to support architectural evolution
Authors: Zhao Jianjun , Yang Hongji , Xiang Liming , Xu Baowen 
Published: October 2002

AbstractChange impact analysis is a useful technique in software maintenance and evolution. Many techniques have been proposed to support change impact analysis at the code level of software systems, but little effort has been made for change impact analysis at the architectural level. In this paper, we present an approach to supporting change impact analysis at the architectural level of software systems based on an architectural slicing and chopping technique. The main feature of our approach is to assess the effect of changes in a software architecture by analyzing its formal architectural specification, and, therefore, the process of change impact analysis can be automated completely. Copyright © 2002 John Wiley & Sons, Ltd.
Behavioural modelling of long‐lived evolution processes—some issues and an example
Authors: Lehman M. M. , Kahen G. , Ramil J. F. 
Published: October 2002

AbstractFor reasons now well understood, application software that is regularly used for real‐world problem solving must be continually adapted and enhanced to maintain its fitness to an ever‐changing real world, its applications and application domains. This type of activity is termedprogressive. As evolution continues, the complexity (functional, structural) of the evolving system is likely to increase unless work, termedanti‐regressive, is undertaken to control and even reduce it. However, with progressive and anti‐regressive work naturally competing for the same pool of resources, management requires means to estimate the amount of work and resources to be applied to each of the two types. After providing a necessary background, the paper describes a systems dynamics model that can serve as the core of a tool to support decision making regarding the optimal personnel allocation over the system lifetime. The model is provided as an example of the use of formalisms in modelling the behaviour of the evolution process. Copyright © 2002 John Wiley & Sons, Ltd.
Physicians' perceptions of menopause and prescribing practices in Morocco
Authors: Obermeyer C.M. , Sahel A. , Hajji N. , Schulein M. 
Published: October 2002

AbstractObjective: To investigate the prescribing practices of Moroccan physicians around menopause. Methods: A survey was carried out on a representative sample of physicians in the capital city Rabat. The sample included general practitioners, gynecologists, cardiologists and rhumatologists, practicing in both public and private facilities. The instrument consisted of close‐ and open‐ended questions about the socio‐demographic characteristics of physicians, their patient population, their prescribing practices, and their perceptions of menopause and the different medical approaches to managing the symptoms and risks associated with it. Results: Most of the physicians interviewed are positively inclined towards the notion of prevention and in favor of hormonal treatment, and approximately half report that they have prescribed hormone therapy. Gynecologists and male physicians prescribe hormones more frequently, as well as physicians who are at private facilities. These findings are discussed in relation to the physicians' perceptions of the menopause transition. Conclusion: There are considerable variations in prescribing practices and perceptions of menopause among Moroccan physicians.
Route of breech delivery and maternal and neonatal outcomes
Authors: Sanchez‐Ramos L , Wells T.L , Adair C.D , Arcelin G , Kaunitz A.M , Wells D.S 
Published: October 2002

AbstractObjective: To compare maternal and neonatal outcomes in elective cesarean vs. attempted vaginal delivery for breech presentation at or near term. Methods: We reviewed the maternal and neonatal charts of all singleton breech deliveries of at least 35 weeks’ gestation or 2000 g delivered between 1986 and 1997 at our institution. Patients delivered by elective cesarean were compared to those attempting a vaginal delivery. The neonatal outcomes analyzed were: corrected mortality; Apgar scores less than 7 at 5 min; abnormal umbilical cord blood gases; birth trauma; and admissions to the intensive care nursery. Maternal morbidity was also assessed and compared. Results: Of 848 women meeting criteria for evaluation, 576 were delivered by elective cesarean while 272 attempted a vaginal delivery. Of 272 women undergoing a trial of labor, 203 (74.6%) were delivered vaginally, while 69 (25.4%) failed an attempt at vaginal delivery and underwent a cesarean. When comparing patients delivered by elective cesarean with those attempting a vaginal delivery, no significant differences were noted in neonatal outcomes. However, maternal morbidity was higher among women delivered by cesarean, regardless of the indications for the procedure. Similar neonatal and maternal results were noted when nulliparous patients were analyzed separately. Conclusions: Cesarean delivery of selected near‐term infants presenting as breech is associated with increased maternal morbidity without corresponding improvement in neonatal outcomes.
Brachial plexus injury and obstetrical risk factors
Authors: Bar J , Dvir A , Hod M , Orvieto R , Merlob P , Neri A 
Published: October 2002

AbstractObjective: To determine whether known historical risk factors of brachial plexus injury differ between affected neonates and healthy controls. Methods: The files of all 62 children with Erb's palsy who were diagnosed after birth were reviewed. The control group consisted of 124 randomly selected uninjured infants born within the same period. Results: Compared with the control group, the mothers of the neonates with brachial plexus injury were found to be significantly older (32.1±5.2 years vs. 28.9±5.8 years, P=0.01), and had a significantly higher incidence of diabetic pregnancy (69% vs. 14.5%, P=0.001); the infants had a significantly higher mean birth weight (3846±576 g vs. 3220±582 g, P=0.0001) and higher incidence of birth weight ≥4000 g (27% vs. 4.8%, P=0.0001). Two of the infants in the study group (3.2%) were born by elective cesarean section. Conclusions: Brachial plexus injury is associated with several non‐predictable or preventable risk factors.