bluuebunny/crossref_metadata_2025_split huggingface dataset:
Studies on hydrolytic degradation of epoxy‐polyester resins cured with glutaric anhydride
Authors: łukaszczyk Jan , Jaszcz Katarzyna 
Published: January 2003

AbstractBiodegradable epoxy‐polyester resins were synthesized in two steps: (1) synthesis of the polyesters with allyl pendent groups; (2) epoxidation of allyl groups in the polyesters. Polyesters with allyl pendent groups were synthesized by melt copolymerization of succinic anhydride (SA) and allyl glycidyl ether (AGE) in the presence of benzyltrimethylammonium chloride (BTMAC) as a catalyst. Functionality of some polyesters was reduced by replacing a part of AGE with butyl glycidyl ether (BGE). The epoxidation of the polyesters obtained was carried out using m‐chloroperbenzoic acid (MCPBA). The multifunctional epoxy‐polyester resins were cured using different amounts of glutaric anhydride (GA) and without use of it. The cured resins were degraded in aqueous buffer of pH = 7.4 at 70 and 37 °C. The hydrolytic degradation was monitored by determination of mass loss. Fracture surfaces of the samples were examined by scanning electron microscopy. Influence of the composition of initial resins and amount of GA used on the hydrolytic degradation was studied. The products of degradation were identified by HPLC and 1H‐NMR. Copyright © 2003 John Wiley & Sons, Ltd.
Advanced environment‐friendly polymer materials
Authors: Ioelovich M. , Figovsky O. 
Published: January 2003

AbstractNovel environment‐friendly hydrophobic polymer materials–layer composites–were developed. These composites consist of a thick layer of cellulose substrate and a thin protective layer of a biodegradable polymer. Various types of the layer composites and their applications were described. Correlation between a porous structure of the protective polymer layer and composite properties was found. Wastes of the novel polymer materials can be utilized in two ways: by repulping and by biodegradation. Widespread usage of the proposed polymer composite materials will bring about an improvement in the ecological state of the environment. Copyright © 2003 John Wiley & Sons, Ltd.
Sociocultural and individual influences on muscle gain and weight loss strategies among adolescent boys and girls
Authors: RICCIARDELLI LINA A. , McCABE MARITA P. 
Published: January 2003

AbstractThe study examined the role of body dissatisfaction, body image importance, sociocultural influences (media and parent and peer encouragement), self‐esteem and negative affect on body change strategies to decrease weight and increase muscles in adolescent boys and girls. Surveys were administered to 587 boys and 598 girls aged between 11 and 15 years. For both genders, parent and peer encouragement and negative affect were the primary predictors of body dissatisfaction, body image importance and strategies to decrease weight and increase muscles. In addition, body image importance was a significant factor in the development of both types of body change strategies, while the media only predicted strategies to decrease weight. Lastly, the effects of self‐esteem were mediated by body dissatisfaction. For boys, a stronger focus on body importance occurred among the boys who were generally satisfied with their bodies while the reverse was the case for girls. © 2003 Wiley Periodicals, Inc. Psychol Schs 40: 209–224, 2003.
Written emotional expression as an intervention for asthma
Authors: BRAY MELISSA A. , THEODORE LEA A. , PATWA SHAMIM S. , MARGIANO SUZANNE G. , ALRIC JOLIE M. , PECK HEATHER L. 
Published: January 2003

AbstractThis investigation employed a multiple baseline design across five participants to examine written emotional expression as an intervention to improve lung function in high school‐aged students, college students, and adults with asthma. The predicted forced expiratory volume in 1 second (FEV1 measure of large airway functioning) and forced expiratory flow (FEF25–75 measure of small airway functioning) were evaluated using spirometry. In addition, anxiety was measured using state and trait anxiety self‐report scales. Generally, results were effective. Individuals with asthma are at higher risk for increased hospitalization and death. For the school‐aged population, asthma is associated with increased absenteeism, restriction of various class activities such as physical education, and poor relationships with peers. Therefore, adults and children with asthma are in need of services and school psychologists appear uniquely qualified to intervene. More recently, the role of the school psychologist is diversifying with corresponding training (e.g., wellness, consultation, prevention, assessment and treatment of health issues) in the areas of health‐related disorders that involve a psychological component. © 2003 Wiley Periodicals, Inc. Psychol Schs 40: 193–207, 2003.
Student sexual orientation, promiscuity and urban acculturation as factors that influence teacher judgments about HIV+ students
Authors: CRUCE MICHAEL K. , STINNETT TERRY A. , CHOATE KURT T. 
Published: January 2003

AbstractAttributions toward HIV+ adolescents made by teacher education students who graduated from rural or urban high schools were examined. Participants read vignettes in which level of promiscuity and sexual orientation were varied, then completed a rating scale that reflected various attitudes toward HIV+ students. The vignette student labeled promiscuous was blamed and judged more personally responsible for contracting the disease than the non‐promiscuous student. Participants who reported graduating from urban high schools indicated more positive affect and positive attitude toward integration, but also higher levels of fearfulness, than did those from rural high schools. Sexual orientation and the participant's high school location interacted on the need for reporting/precautions variable. Those from urban high schools indicated a higher need for reporting and safety precautions than did those from rural high schools when the HIV+ student was labeled heterosexual. School Psychologists should be aware of the varied factors that are involved in teacher judgments concerning HIV+ students. © 2003 Wiley Periodicals, Inc. Psychol Schs 40: 173–182, 2003.
Comparison of a QM/MM force field and molecular mechanics force fields in simulations of alanine and glycine “dipeptides” (Ace‐Ala‐Nme and Ace‐Gly‐Nme) in water in relation to the problem of modeling the unfolded peptide backbone in solution
Authors: Hu Hao , Elstner Marcus , Hermans Jan 
Published: January 2003

AbstractWe compare the conformational distributions of Ace‐Ala‐Nme and Ace‐Gly‐Nme sampled in long simulations with several molecular mechanics (MM) force fields and with a fast combined quantum mechanics/molecular mechanics (QM/MM) force field, in which the solute's intramolecular energy and forces are calculated with the self‐consistent charge density functional tight binding method (SCCDFTB), and the solvent is represented by either one of the well‐known SPC and TIP3P models. All MM force fields give two main states for Ace‐Ala‐Nme, β and α separated by free energy barriers, but the ratio in which these are sampled varies by a factor of 30, from a high in favor of β of 6 to a low of 1/5. The frequency of transitions between states is particularly low with the amber and charmm force fields, for which the distributions are noticeably narrower, and the energy barriers between states higher. The lower of the two barriers lies between α and β at values of ψ near 0 for all MM simulations except for charmm22. The results of the QM/MM simulations vary less with the choice of MM force field; the ratio β/α varies between 1.5 and 2.2, the easy pass lies at ψ near 0, and transitions between states are more frequent than for amber and charmm, but less frequent than for cedar. For Ace‐Gly‐Nme, all force fields locate a diffuse stable region around ϕ = π and ψ = π, whereas the amber force field gives two additional densely sampled states near ϕ = ±100° and ψ = 0, which are also found with the QM/MM force field. For both solutes, the distribution from the QM/MM simulation shows greater similarity with the distribution in high‐resolution protein structures than is the case for any of the MM simulations. Proteins 2003;50:451–463. © 2003 Wiley‐Liss, Inc.
Basic interdomain boundary residues in calmodulin decrease calcium affinity of sites I and II by stabilizing helix–helix interactions
Authors: Faga Laurel A. , Sorensen Brenda R. , VanScyoc Wendy S. , Shea Madeline A. 
Published: January 2003

AbstractCalmodulin is an EF‐hand calcium‐binding protein (148 a.a.) essential in intracellular signal transduction. Its homologous N‐ and C‐terminal domains are separated by a linker that appears disordered in NMR studies. In a study of an N‐domain fragment of Paramecium CaM (PCaM1–75), the addition of linker residues 76 to 80 (MKEQD) raised the Tm by 9°C and lowered calcium binding by 0.54 kcal/mol (Sorensen et al., Biochemistry 2002;41:15–20), showing that these tether residues affect energetics as well as being a barrier to diffusion. To determine the individual contributions of residues 74 through 80 (RKMKEQD) to stability and calcium affinity, we compared a nested series of 7 fragments (PCaM1–74 to PCaM1–80). For the first 4, PCaM1–74 through PCaM1–77, single amino acid additions at the C‐terminus corresponded to stepwise increases in thermostability and decreases in calcium affinity with a net change of 13.5°C in Tm and 0.55 kcal/mol in free energy. The thermodynamic properties of fragments PCaM1–77 through PCaM1–80 were nearly identical. We concluded that the 3 basic residues in the sequence from 74 to 77 (RKMK) are critical to the increased stability and decreased calcium affinity of the longer N‐domain fragments. Comparisons of NMR (HSQC) spectra of 15N‐PCaM1–74 and 15N‐PCaM1–80 and analysis of high‐resolution structural models suggest these residues are “latched” to amino acids in helix A of CaM. The addition of residues E78, Q79, and D80 had a minimal effect on sites I and II, but they may contribute to the mechanism of energetic communication between the domains. Proteins 2003;50:381–391. © 2003 Wiley‐Liss, Inc.
Seasonal variation of the lipoidal matters and hypolipidaemic activity of the red alga Corallina officinalis L.
Authors: Awad N. E. , Selim M. A. , Saleh M. M. , Matloub A. A. 
Published: January 2003

AbstractThe lipoidal matters of Corallina officinalis L. showed a seasonal nonsignificant quantitative variation. However, the fatty acids revealed a relative increase in the summer and winter, while unsaponifiable matter exhibited a slight increase in the spring. The GC/MS analysis of saponifiable and unsaponifiable matter of the algal samples collected in different seasons revealed that samples collected in the spring contained a low cholesterol content and high steroidal compounds as well as high polyunsaturated fatty acids. The alcohol extract, hexane extract and fatty acid fraction of this algal sample exhibited a significant hypolipidaemic activity. Also, two biologically active fractions of hydrocarbons were isolated by CC technique from the hexane fraction of C. officinalis L. and identified by GC/MS. Copyright © 2003 John Wiley & Sons, Ltd.
Hepatoprotective and antihyperliposis activities of in vitro cultured Anoectochilus formosanus
Authors: Du Xiao‐Ming , Sun Ning‐Yi , Hayashi Jun , Chen Yang , Sugiura Minoru , Shoyama Yukihiro 
Published: January 2003

AbstractThe pharmacological effects of an aqueous extract of the whole plants of in vitro cultured Anoectochilus formosanus were investigated experimentally for hepatoprotective and antihyperliposis activities. The extract showed significant antihepatotoxic activity against carbon tetrachloride induced cytotoxicity in primary cultured rat hepatocytes. In an assay for antihyperliposis using aurothioglucose‐induced obese mice, the extract suppressed significantly the increase in the weights of body and liver, ameliorated triglyceride levels in the liver and serum, and also significantly reduced the deposition of adipose tissue. Copyright © 2003 John Wiley & Sons, Ltd.
In vitro immunomodulatory activity of flavonoid glycosides from Urtica dioica L.
Authors: Akbay Pinar , Basaran A. Ahmet , Undeger Ulkü , Basaran Nursen 
Published: January 2003

AbstractThe major compounds isolated from the methanolic extract of the aerial parts of Urtica dioica L. were determined as quercetin‐3‐O‐rutinoside (1), kaempherol‐3‐O‐rutinoside (2) and isorhamnetin‐3‐O‐glucoside (3) by chromatographic, chemical (acidic hydrolysis) and spectral (UV, IR, 1H‐NMR, 13C‐NMR) methods. Their immunomodulatory activities were studied in vitro by chemotaxis (Boyden Migration Chamber) and intracellular killing activity (NBT reduction) tests. Compounds 1, 2, 3 and the total flavonoid fraction were determined to have significant chemotactic effects in 4, 8, 16 μg doses. According to the results of the NBT reduction test, all flavonoid glycosides showed high intracellular killing activity. The results of both assays confirmed the immunostimulatory activity of the flavonoid fraction and the isolated flavonoid glycosides on neutrophils suggesting that they could possibly be useful for treating patients suffering from neutrophil function deficiency and chronic granulomatous diseases. Copyright ­© 2003 John Wiley & Sons, Ltd.
Anticonvulsant effect of FS‐1 subfraction isolated from roots of Delphinim denudatum on hippocampal pyramidal neurons
Authors: Raza Mohsin , Shaheen Farzana , Choudhary M. I. , Rahman Atta‐ur‐ , Sombati Sompong , Suria Amin , Rafiq Azhar , DeLorenzo R. J. 
Published: January 2003

AbstractThe effects were investigated of a partially purified subfraction (FS‐1) isolated from Delphinium denudatum on sustained repetitive firing (SRF) of cultured neonatal rat hippocampal pyramidal neurons. The blockade of sustained repetitive firing is one of the basic mechanisms of antiepileptic drugs at the cellular level. Using the whole cell current‐clamp technique, sustained repetitive firing was elicited in pyramidal neurons under study by a depolarizing pulse of 500 ms duration, 0.3 Hz and 0.1–0.6 nA current strength. FS‐1 (0.01–0.06 mg/mL) reduced the number of action potentials per pulse in a dose‐dependent manner until no action potentials were elicited for the remainder of the pulse. There was a corresponding use‐dependent reduction in amplitude and V
max of action potentials. The V
max of action potential 1 exhibited a dose‐dependent reduction. At a dose of 0.06 mg/mL FS‐1 reduced V
max to 29%–38% and amplitude to 16%–20 % of the control values. The blockade of sustained repetitive firing by FS‐1 was reversed by hyperpolarization of the membrane potential (−65 to −75 mV) while depolarization of the membrane potential (−53mV to −48 mV) potentiated the block. The results suggest that FS‐1 blocks sustained repetitive firing in hippocampal neurons in a use‐dependent and voltage‐dependent manner similar to the prototype anticonvulsant drug, phenytoin. However, unlike phenytoin, which binds preferably to the inactive state, the compounds present in FS‐1 also interacted with the resting state of the Na+ channels by reducing V
max of action potential 1. The results indicate that the partially purified FS‐1 subfraction of Delphinium denudatum contains a potent anticonvulsant compound. Copyright © 2003 John Wiley & Sons, Ltd.
Correction of haemorheological disturbances in myocardial infarction by diquertin and ascorbic acid
Authors: Plotnikov M. B. , Aliev O. I. , Maslov M. Ju , Vasiliev A. S. , Tjukavkina N. A. 
Published: January 2003

AbstractIn a model of the high blood viscosity syndrome, developed after myocardial infarction in rats, it was observed that a therapy of a combination of diquertin (20 mg/kg) and ascorbic acid (50 mg/kg) for a ­period of 6 days, resulted in an improvement of haemorheological indices. The decrease in blood ­viscosity was primarily due to an improved deformability of erythrocytes, and to some extent, due to a decrease in the content of plasma fibrinogen and erythrocyte aggregation. Copyright © 2003 John Wiley & Sons, Ltd.
Plants with traditional uses and activities, relevant to the management of Alzheimer's disease and other cognitive disorders
Authors: Howes Melanie‐Jayne R. , Perry Nicolette S. L. , Houghton Peter J. 
Published: January 2003

AbstractIn traditional practices of medicine, numerous plants have been used to treat cognitive disorders, including neurodegenerative diseases such as Alzheimer's disease (AD) and other memory related disorders. An ethnopharmacological approach has provided leads to identifying potential new drugs from plant sources, including those for memory disorders. There are numerous drugs available in Western medicine that have been directly isolated from plants, or are derived from templates of compounds from plant sources. For example, some alkaloids from plant sources have been investigated for their potential in AD therapy, and are now in clinical use (e.g. galantamine from Galanthus nivalis L. is used in the United Kingdom). Various other plant species have shown favourable effects in AD, or pharmacological activities indicating the potential for use in AD therapy. This article reviews some of the plants and their active constituents that have been used in traditional medicine, including Ayurvedic, Chinese, European and Japanese medicine, for their reputed cognitive‐enhancing and antidementia effects. Plants and their constituents with pharmacological activities that may be relevant to the treatment of cognitive disorders, including enhancement of cholinergic function in the central nervous system, anti‐cholinesterase (anti‐ChE), antiinflammatory, antioxidant and oestrogenic effects, are discussed. Copyright © 2003 John Wiley & Sons, Ltd.
Standard Operating Procedures for clinical research personnel – Part 15
Authors: Bohaychuk Wendy , Ball Graham 
Published: January 2003

AbstractThis is the 15th in a series of articles containing proposals for wording and content of Standard Operating Procedures (SOPs) for clinical research activities conducted by sponsors and Contract Research Organisations (CROs). The procedures include those required by the International Conference on Harmonisation (ICH), the Food and Drug Administration (FDA), many other guidelines and regulations, and ‘best practice’ observed by the authors. The model forms require modification for actual use. In this article, SOPs are presented for review of source documents and case report forms: source documents versus Case Report Forms [CRFs] (SOP 403) and source data verification and CRF review at study sites (SOP 404). (The full text of all 101 SOPs is available from the authors.) Copyright © 2003 John Wiley & Sons, Ltd.
Principles in quality assurance. Part 2. Don't hide behind the regulations
Authors: Jones Anthony B. 
Published: January 2003

AbstractIn order to achieve and sustain effective compliance with the quality regulations, an understanding of the rationale for compliance must be developed throughout an organization. Developing such an organizational understanding is difficult to attain through training based solely on the text of the regulations or the company's Standard Operating Procedures (SOPs). These do have their place, but there is too much information, and the effects of training dissipate rapidly because personnel cannot effectively retain detailed information. In our organization, we undertook a process of simplification of the regulations, in an attempt to define the smallest number of basic quality principles that are embodied in Good Laboratory Practice (GLP) and associated regulations. The systematic application of these quality principles is a mechanism by which Quality Assurance (QA) can be clear and consistent in its monitoring and training activities. This process empowers all personnel to make correct compliance decisions without having to consult the detail of the regulations at every turn. The establishment and application of this concept at a bioanalytical contract research laboratory is described in this article. Copyright © 2003 John Wiley & Sons, Ltd.
Interference avoidance and multiuser MIMO systems
Authors: Popescu Dimitrie C. , Rose Christopher 
Published: January 2003

AbstractWe apply interference avoidance methods to multiuser systems with multiple inputs and multiple outputs (MIMO) such as would be used on the uplink (or in overlapping downlink footprints) for satellite systems with multiple antennas. An arbitrary signal space can be used and the method can be applied to any MIMO system model regardless of the choice signal basis functions. Information is transmitted via multicode CDMA where symbols that comprise the data frame from a given user are ‘spread’ over the available dimensions using a precoding matrix. Optimal precoding matrices that maximize signal‐to‐interference plus noise‐ratio for all symbols/users are then obtained by application of distributed greedy interference avoidance methods. In general, algorithms based on greedy interference avoidance are different from water filling schemes. However, the codeword ensembles obtained provide similar simultaneous water filling solutions and thus maximize sum capacity. Numerical simulations have been performed and the signal‐to‐noise ratio distribution for receiver antennas and complementary cumulative distribution functions for sum capacity with optimal precoding matrices are also presented. Copyright © 2003 John Wiley & Sons, Ltd.
Adaptive parallel interference cancellation receiver in CDMA satellite system
Authors: Zhang Lei , Zhu Jinkang 
Published: January 2003

AbstractFuture satellite communication systems will be characterized by broadband, multimedia services, and large capacity of mobile terminals. Low Earth Orbit (LEO) system with multiple spot‐beams per satellite using Code Division Multiple Access (CDMA) is a good choice. In this paper, an adaptive parallel interference cancellation detector is proposed for reverse link with both intra‐beam and inter‐beam multiple access interference (MAI). The proposed linear adaptive receiver achieves essential advantages with respect to MAI with a little more complex than the conventional matched‐filter receiver. The receiver structure is all feed‐forward and more stable than many other multiuser detectors. We then study several adaptive algorithms with the aid of training sequence, and compare them with blind algorithm in order to find the good tradeoff among the performance, complexity and bandwidth‐extension. With only small modification, the receiver can work well in multirate cases which are usually hopeful in multimedia services. With the test of simulations under AWGN and time‐varying Rician channels, the proposed receiver can reach good performance with considerable increasing user capacity. Copyright © 2003 John Wiley & Sons, Ltd.
A low complexity partially adaptive CDMA receiver for downlink mobile satellite communications
Authors: Lin Gau‐Joe , Lee Ta‐Sung 
Published: January 2003

AbstractA novel CDMA receiver with enhanced interference suppression is proposed for pilot symbols assisted mobile satellite systems in the presence of frequency offset. The design of the receiver involves the following procedure. First, adaptive correlators are constructed at different fingers, based on the scheme of generalized sidelobe canceller (GSC), to collect the multipath signals and suppress multi‐access interference (MAI). In particular, a partially adaptive (PA) realization of the GSC correlators is proposed based on the Krylov subspace technique, leading to an efficient algorithm without the need of complicated matrix computations. Second, pilot symbols assisted frequency offset estimation, channel estimation and RAKE combining give the estimate of signal symbols. Finally, further performance enhancement is achieved by an iterative scheme in which the signal is reconstructed and subtracted from the GSC correlators input, leading to faster convergence of the receiver. The proposed low complexity PA receiver is suitable or the downlink of mobile satellite CDMA systems, and shown to outperform the conventional fully adaptive MMSE receiver by using a small number of pilot symbols. Copyright © 2003 John Wiley & Sons, Ltd.