bluuebunny/crossref_metadata_2025_split huggingface dataset:
Influence of matching thickness on the absorption properties of doped barium ferrites at microwave frequencies
Authors: Ghasemi A. , Saatchi A. , Salehi M. , Hossienpour A , Morisako A. , Liu X. 
Published: January 2006

AbstractThe development and characterization of hexagonal ferrite powders of BaFe9Mn1.5Ti1.5O19, BaFe9Mn1.5Co1.5O19, and BaFe9Ti1.5Co1.5O19 as the microwave absorbers have been investigated. The ferrites were fabricated by conventional ceramic technology. The developed ferrite powders 80% by weight were mixed with polyvinylchloride plasticizer and fired to form rubber‐ferrite with the thickness of 1.5 mm, 2 mm and 2.5 mm. XRD was used to identify structures of the samples. The magnetoplumbite structures for all the samples have been formed. Vibrating sample magnetometer was used to determine the hysteresis loops of barium ferrite and BaFe9Mn1.5Ti1.5O19 at room temperature. The vector network analyzers in the frequency range of 12 to 20 GHz have measured the reflection loss properties of rubber‐ferrite. It was concluded that BaFe9Mn1.5Ti1.5O19 with thickness of 2 mm could be designed as a wide‐band microwave absorber. By SEM, the size and morphology of grains in BaFe9Mn1.5Ti1.5O19 ferrite were examined. The results showed that ferrite with grain size of 5 µm do not have any impurities. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Vacancy‐type defects and electronic structure of perovskite‐oxide SrTiO3 from positron annihilation
Authors: Hamid A. S. , Uedono A. , Chikyow T. , Uwe K. , Mochizuki K. , Kawaminami S. 
Published: January 2006

AbstractThe vacancy‐type defects in Nb‐doped SrTiO3 and in undoped SrTiO3, annealed in H2 flow, were investigated by means of positron lifetime and 2D angular correlation of annihilation radiation (ACAR) experiments. The calculations of the lifetime of positron were performed by using atomic superposition (AT‐SUP) method. The results showed that positrons annihilate from a free state in the Nb‐doped SrTiO3. The trapping centers in the annealed sample were found to be oxygen vacancies VO associated with relaxation of the surrounding ions. Moreover, the momentum distributions of the samples studied were correlated to the variation of their electronic structure. It was proposed from the drastic change in the momentum distribution upon introduction of VO, that 2D‐ACAR technique is a sensitive tool for acquiring information on the electronic and bond structure of the perovskite‐oxides. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Analysis of exponent values in Gaussian‐type functions for development of protonic and deuteronic basis functions
Authors: Ishimoto Takayoshi , Tachikawa Masanori , Nagashima Umpei 
Published: January 2006

AbstractWe analyzed the exponent (α) values in Gaussian‐type functions (GTF) for protons and deuterons in BH3, CH4, NH3, H2O, HF, and their deuterated molecules for the development of nuclear basis functions, which are used for molecular orbital (MO) calculations that directly include nuclear quantum effects. The optimized α (αopt) value in the single s‐type ([1s]) GTF for protons is changed due to the difference in flexibility of the electronic basis sets. The difference between the energy obtained by using the αopt value for each molecule and that obtained by using the average α (αave) value for these exponents with the 6‐31G(d,p) electronic basis function is only 2 × 10−5 a.u. The αave values of protonic and deuteronic [1s] GTFs by the present calculation are 24.1825 and 35.6214, respectively. We found that the αave values enable the evaluation of the total energy and the geometrical changes in hydrogen bonding, such as O…HO, O…HN, and O…HC, while the αopt value became small by forming a hydrogen bond. The result using only the [1s] GTF for the protonic and deuteronic basis functions is sufficient to explain the differences of energy and geometry induced by the H/D isotope effect, although the total energy of ∼5 × 10−4 a.u. was improved by using the s‐, p‐, and d‐type ([1s1p1d]) GTFs for protons and deuterons. We clearly demonstrate that the protonic and deuteronic basis functions based on the αave value enable us to apply the method to other sample molecules (glycine, malonaldehyde, and formic acid dimer). The protonic and deuteronic basis functions we developed treat the quantum effects of protons and deuterons effectively and extend the application range of the MO calculation to include nuclear quantum effects. © 2006 Wiley Periodicals, Inc. Int J Quantum Chem, 2006
Approaches and requirements to develop and improve the standard processes for a research and development organization
Authors: Hwang Young Ha , Park Jong‐Geun 
Published: January 2006

AbstractWith the increased complexity of man‐made systems and software and the higher quality R&D results that are expected in today's R&D environment, it has become increasingly necessary to effectively define and improve the R&D standard processes specifically tailored for our organization and projects. To meet these needs, we have defined R&D standard processes based on international standards for systems and software engineering and on our existing traditional work methods, and then applied them to our ongoing projects. Now, we are improving our defined R&D standard processes continuously by monitoring of our processes and products and checking feedback from application results. In this paper, we introduce the R&D standard processes developed by our organization, the E Research Institute in Korea, and define the requirements and approaches used for their development and improvement. We compare our defined R&D standard processes with ISO/IEC 15288, which is the international standards for systems engineering, and summarize what we have learned through the development and improvement of our processes. © 2006 Wiley Periodicals, Inc. Syst Eng 9: 35–44, 2006
Inhibition of benzo(a)pyrene‐induced cell cycle progression by all‐trans retinoic acid partly through cyclin D1/E2F‐1 pathway in human embryo lung fibroblasts
Authors: Jia Xiaowei , Liu Bingci , Shi Xianglin , Gao Ai , You Baorong , Ye Meng , Shen Fuhai , Du Hongju 
Published: January 2006

AbstractBenzo(a)pyrene [B(a)P] is a potent environmental carcinogen, which induces cell cycle changes. All‐trans retinoic acid (ATRA) is a promising agent in prevention and treatment of human cancers. In the present study, we investigated the inhibition of B(a)P‐induced cell cycle progression by ATRA in human embryo lung fibroblast (HELF). Our results showed that after treatment with B(a)P, the expression of cyclin D1 and E2F‐1 were both increased significantly in HELF. There were almost no changes of CDK4 and E2F‐4 expression by treatment with B(a)P. As expected, pretreatment with ATRA could efficiently decrease B(a)P‐induced overexpression of cyclin D1 and E2F‐1. In a further study, we stably transfected antisense cyclin D1 and antisense CDK4 plasmid into HELF. The inhibition of cyclin D1 expression and the inhibition of CDK4 expression significantly impaired the B(a)P‐induced overexpression of E2F‐1 respectively. Pretreatment with ATRA, cells expressing antisense cyclinD1 or antisense CDK4 showed a lesser decrease of B(a)P‐induced overexpression of E2F‐1 compared with similarly treated HELF. Furthermore, flow cytometry analysis showed that B(a)P promoted cell cycle progression from G1 phase to S phase, while pretreatment with ATRA could inhibit B(a)P‐induced cell cycle progression by an accumulation of cells in the G1 phase. It was suggested that ATRA could block B(a)P‐induced cell cycle promotion partly through the cyclin D1/E2F‐1 pathway in HELF.
Cytoplasmic dynein/dynactin function and dysfunction in motor neurons
Authors: Levy Jennifer R. , Holzbaur Erika L.F. 
Published: January 2006

AbstractThe microtubule motor protein cytoplasmic dynein and its activator dynactin are essential in higher eukaryotes, due to critical roles in vesicular transport and cell division. Neurons are uniquely sensitive to defects in dynein/dynactin function, which affect retrograde axonal transport, neurotrophic factor signaling, neurofilament transport, mRNA localization, neuronal migration, and protein recycling and degradation. Mutations in either dynein or dynactin lead to motor neuron degeneration and loss. Recent progress in understanding the cellular mechanisms of dynein/dynactin function, and the effects of dynein/dynactin dysfunction has provided new insight into the roles of microtubule‐based motility in the neuron.
Zinc uptake is mediated by M1 muscarinic acetylcholine receptors in differentiated SK‐SH‐SY5Y cells
Authors: Zuchner T. , Schliebe N. , Schliebs R. 
Published: January 2006

AbstractAlzheimer's disease (AD), the most prevalent form of dementia, is characterized by several major morphological hallmarks such as senile plaques, neurofibrillary tangles and a loss of cholinergic basal forebrain neurons. Apart from cholinergic markers like choline acetyltransferase and acetylcholinesterase, there have been reports on changes in muscarinic acetylcholine receptors (mAChR) as well as on influences of zinc metabolism in the disease. As recent studies gave hints about a possible link between mAChRs and zinc uptake, the human neuroblastoma cell line SK‐SH‐SY5Y was used to evaluate the role of M1‐mAChR on zinc uptake. Zinc levels were semi‐quantitatively detected by using the zinc‐specific fluorophor Zn‐AF2‐DA.In the presence of 1 μM extracellular zinc, M1‐mAChR stimulation with talsaclidine increased intracellular zinc levels as did stimulation of PKC by phorbol esters. Furthermore, the effect of extracellular zinc on the expression of the zinc finger protein PNUTS (protein phosphatase 1 nuclear targeting subunit 10) was investigated and revealed an upregulation of PNUTS expression in the presence of 1 μM extracellular zinc by 294% when compared to incubation in zinc free medium. In summary, this report demonstrates that intracellular zinc uptake in SK‐SH‐SY5Y cells is controlled by M1‐mAChR mediated signalling pathways and that zinc may act as a cofactor for transcriptional regulation of zinc finger genes such as PNUTS.
A comparative model of firm size and the global operational dynamics of U.S. firms in Europe
Authors: Prater Edmund , Ghosh Soumen 
Published: January 2006

AbstractThis study focuses on the global operations of U.S. firms that have shifted from direct exporting to the location of facilities in Europe. All U.S. firms with physical facilities in Europe were surveyed. We develop a general model that integrates firms’ experience in global operations with their operations strategy, their global supply chain structure, and their ability to coordinate global operations through information technology. From the model emerge hypotheses that are tested using the structural equation modeling approach, taking into account differences in challenges across small‐ and medium‐sized enterprises (SMEs) and large to very large firms. Our testing and comparisons give insight into the dynamics of the globalization process and provide direction for future research.
Deaths from all causes in a long-term follow-up study of 11583 deliberate self-harm patients
Authors: HAWTON K. , HARRISS L. , ZAHL D. 
Published: January 2006

Background. Deliberate self-harm (DSH) may be associated with increased risk of death from a variety of causes, not just suicide.Method. A follow-up study of 11583 DSH patients who presented to a general hospital over a 20-year period was conducted to examine risk of death from a range of causes during a follow-up period of between 3 and 23 years. Deaths were identified through national death registries. Expected numbers of deaths were calculated from national death statistics.Results. The number of deaths (1185, 10·2%) was 2·2 times the expected number, the excess being significantly greater in males than females. Suicides were 17 times more frequent than expected and undetermined causes of death and accidental poisonings 15 times more frequent. Significantly more than expected numbers of deaths from most natural causes were found, including respiratory disease, circulatory, neurological, endocrine, digestive, skin and musculoskeletal and connective tissue disorders, and symptoms, signs and ill-defined conditions. Deaths due to accidents other than poisoning were more frequent than expected in both genders and homicides more frequent in males.Conclusions. In addition to increased risk of suicide, DSH patients are at increased risk of dying from a wide range of other causes. Possible explanations include lifestyle factors, physical disorders contributing to initial risk of DSH, and social disadvantage. The findings are relevant to clinical management and evaluation of outcome and health-care costs associated with DSH.
Tamoxifen (ICI46,474) as a targeted therapy to treat and prevent breast cancer
Authors: Jordan V Craig 
Published: January 2006

Antihormonal therapy targeted to the oestrogen receptor (OER) is recognized as a significant advance in the treatment and prevention of breast cancer. However, the research method used to achieve the current successes seen in the clinic was not linear but was based on the changing fashions in research and the application of appropriate testing models. The discovery and investigation of nonsteroidal antioestrogens by the pharmaceutical industry during the 1960s was initially an exciting prospect for clinical development. The drugs were superb antifertility agents in laboratory animals, so the prospect of marketing a ‘morning after’ pill was a high priority. Unfortunately, the reproductive endocrinology of the rat was found to be completely different from that of the human. Antioestrogens, in fact, improved fertility by inducing ovulation in subfertile women so much of the drug development was discontinued. The successful reinvention of ICI46,474 from its origins as a failed contraceptive to a pioneering breast cancer treatment targeted to the OER presaged the development of the current menu of medicines targeted to a range of different survival mechanisms in cancer cells.British Journal of Pharmacology (2006) 147, S269–S276. doi:10.1038/sj.bjp.0706399
Neuromuscular block
Authors: Bowman W C 
Published: January 2006

Descriptions of the South American arrow poisons known as curares were reported by explorers in the 16th century, and their site of action in producing neuromuscular block was determined by Claude Bernard in the mid‐19th century. Tubocurarine, the most important curare alkaloid, played a large part in experiments to determine the role of acetylcholine in neuromuscular transmission, but it was not until after 1943 that neuromuscular blocking drugs became established as muscle relaxants for use during surgical anaesthesia. Tubocurarine causes a number of unwanted effects, and there have been many attempts to replace it. The available drugs fall into two main categories: the depolarising blocking drugs and the nondepolarising blocking drugs. The former act by complex mixed actions and are now obsolete with the exception of suxamethonium, the rapid onset and brief duration of action of which remain useful for intubation at the start of surgical anaesthesia. The nondepolarising blocking drugs are reversible acetylcholine receptor antagonists. The main ones are the atracurium group, which possess a built‐in self‐destruct mechanism that makes them especially useful in kidney or liver failure, and the vecuronium group, which are especially free from unwanted side effects. Of this latter group, the compound rocuronium is of especial interest because its rapid onset of action allows it to be used for intubation, and there is promise that its duration of action may be rapidly terminated by a novel antagonist, a particular cyclodextrin, that chelates the drug, thereby removing it from the acetylcholine receptors.British Journal of Pharmacology (2006) 147, S277–S286. doi:10.1038/sj.bjp.0706404
GABA and glycine as neurotransmitters: a brief history
Authors: Bowery N G , Smart T G 
Published: January 2006

γ‐Aminobutyric acid (GABA) emerged as a potentially important brain chemical just over 50 years ago, but its significance as a neurotransmitter was not fully realized until over 16 years later. We now know that at least 40% of inhibitory synaptic processing in the mammalian brain uses GABA. Establishing its role as a transmitter was a lengthy process and it seems hard to believe with our current knowledge that there was ever any dispute about its role in the mammalian brain. The detailed information that we now have about the receptors for GABA together with the wealth of agents which facilitate or reduce GABA receptor mechanisms make the prospects for further research very exciting. The emergence of glycine as a transmitter seems relatively painless by comparison to GABA. Perhaps this is appropriate for the simplest of transmitter structures! Its discovery within the spinal cord and brainstem approximately 40 years ago was followed only 2 years later by the proposal that it be conferred with ‘neurotransmitter’ status. It was another 16 years before the receptor was biochemically isolated. Now it is readily accepted as a vital spinal and supraspinal inhibitory transmitter and we know many details regarding its molecular structure and trafficking around neurones. The pharmacology of these receptors has lagged behind that of GABA. There is not the rich variety of allosteric modulators that we have come to readily associate with GABA receptors and which has provided us with a virtual treasure trove of important drugs used in anxiety, insomnia, epilepsy, anaesthesia, and spasticity, all stemming from the actions of the simple neutral amino acid GABA. Nevertheless, the realization that glycine receptors are involved in motor reflexes and nociceptive pathways together with the more recent advent of drugs that exhibit some subtype selectivity make the goal of designing selective therapeutic ligands for the glycine receptor that much closer.British Journal of Pharmacology (2006) 147, S109–S119. doi:10.1038/sj.bjp.0706443
Potassium channels – multiplicity and challenges
Authors: Jenkinson Donald H 
Published: January 2006

The development of our knowledge of the function, structure and pharmacology of K+ channels is briefly outlined. This is the most diverse of all the ion channel families with at least 75 coding genes in mammals. Alternative splicing as well as variations in the channel subunits and accessory proteins that co‐assemble to form the functional channel add to the multiplicity. Whereas diversity of this order suggests that it may be possible to develop new classes of drug, for example, for immunomodulation and some diseases of the central nervous system, the ubiquity of K+ channels imposes stringent requirements for selectivity. Animal toxins from the snake, bee and scorpion provide useful leads, though only in a few instances (e.g. with apamin) it has been possible to produce non‐peptidic analogues of high potency. The scale of the resources needed to identify, and characterize fully, specific K+ channel as targets and then develop modulators with the required selectivity presents a challenge to both academic and applied pharmacologists.British Journal of Pharmacology (2006) 147, S63–S71. doi:10.1038/sj.bjp.0706447
G‐protein‐coupled receptors: past, present and future
Authors: Hill Stephen J 
Published: January 2006

The G‐protein‐coupled receptor (GPCR) family represents the largest and most versatile group of cell surface receptors. Drugs active at these receptors have therapeutic actions across a wide range of human diseases ranging from allergic rhinitis to pain, hypertension and schizophrenia. This review provides a brief historical overview of the properties and signalling characteristics of this important family of receptors.British Journal of Pharmacology (2006) 147, S27–S37. doi:10.1038/sj.bjp.0706455
The receptor concept: pharmacology's big idea
Authors: Rang H P 
Published: January 2006

Chemical signalling is the main mechanism by which biological function is controlled at all levels, from the single cell to the whole organism. Chemical recognition is the function of receptors, which, in addition to recognising endogenous chemical signals, are also the target of many important experimental and therapeutic drugs. Receptors, therefore, lie at the heart of pharmacology. This article describes the way in which the receptor concept originated early in the 20th century, and evolved through a highly innovative stage of quantitative theory based on chemical kinetics, to the point where receptors were first isolated and later cloned, until we now have a virtually complete catalogue of all the receptors present in the genome. Studies on signal transduction are revealing great complexity in the events linking ligand binding to the physiological or therapeutic response. Though some simple quantitative rules of ‘receptor theory’ are still useful, the current emphasis is on unravelling the pathways that link receptors to responses, and it will be some time before we know enough about them to embark on the next phase of ‘receptor theory’.British Journal of Pharmacology (2006) 147, S9–S16. doi:10.1038/sj.bjp.0706457
Pharmacology of intracellular signalling pathways
Authors: Nahorski Stefan R 
Published: January 2006

This article provides a brief and somewhat personalized review of the dramatic developments that have occurred over the last 45 years in our understanding of intracellular signalling pathways associated with G‐protein‐coupled receptor activation. Signalling via cyclic AMP, the phosphoinositides and Ca2+ is emphasized and these systems have already been revealed as new pharmacological targets. The therapeutic benefits of most of such targets are, however, yet to be realized, but it is certain that the discipline of pharmacology needs to widen its boundaries to meet these challenges in the future.British Journal of Pharmacology (2006) 147, S38–S45. doi:10.1038/sj.bjp.0706468
A brief history of the British Pharmacological Society
Authors: Cuthbert Alan W 
Published: January 2006

The article traces the history of the BPS since its inception in 1931 until the present day. Details are given about the size and nature of the membership and how the governance of the Society has changed during the last 75 years. The emergence of the Clinical Section from within the main Society and the growth of the Society's publications are described.British Journal of Pharmacology (2006) 147, S2–S8. doi:10.1038/sj.bjp.0706496
Microcalcifications of the breast: how does radiologic classification correlate with histology?
Authors: Müller-Schimpfle M. , Wersebe A. , Xydeas T. , Fischmann A. , Vogel U. , Fersis N. , Claussen C. D. , Siegmann K. 
Published: January 2006

Purpose: To assess the correlation between the pre-biopsy classification of microcalcifications and the underlying histology. Material and Methods: Using the morphology and distribution patterns according to the Breast Imaging-Reporting and Data System (BI-RADS®) lexicon, the microcalcifications of 199 lesions in 163 consecutive patients scheduled to undergo 11 G vacuum core biopsy were classified within the BI-RADS® categories. The correlation between BI-RADS® assessment categories 3, 4, and 5 and the final histological results was statistically evaluated with the χ2 test. The diagnostic indices were calculated. Results: The prospectively classified BI-RADS® 3/4/5 findings revealed a malignant histology in 5.9%/17.6%/90.9% of all lesions, respectively. The relationship between BI-RADS® categories 3, 4, and 5 and histology was statistically highly significant ( P<0.0001). The sensitivity, specificity, positive and negative predictive values were 95.7%/21.2%/37.8%/94.3%, respectively. Conclusion: The BI-RADS® lexicon describes microcalcifications of the breast and provides diagnostic categories that lead to standardized biopsy recommendations. Nevertheless, how to link description to classification of microcalcifications is still a difficult diagnostic task. The evaluation of microcalcifications as proposed in this article may help to set standards in the clinical routine and in the comparability of scientific data.