bluuebunny/crossref_metadata_2025 huggingface dataset:
Models forCNSMalignancies
Authors: Pilkington Geoffrey J. , Parker Katharine A.
Published: October 2007

Primary or intrinsic central nervous system (CNS) tumours, which affect the brain, spinal cord, and cranial nerves, are derived from the CNS substance itself, with the majority of them emanating from neuroglial cells or their progenitors. These tumours are, generally, collectively known asgliomas. Although such neoplasms are quite amenable to cell culture and the established cell lines are numerous, the original tumours display a high degree of cellular heterogeneity, while resultant high‐passage cultures suffer from homogeneity due toin vitroselection, thereby limiting their value in biological studies. Monolayer cultures have, however, been used extensively for drug chemosensitivity and multidrug resistance studies, as well as for studies of adhesion, motility, and invasiveness. The use of three‐dimensional (3D) multicellular tumour spheroids (MCTSs) has gained much support in recent years often in the context of “confrontation” cultures, where a 3D “target” tissue of precultured heart fragment or re‐aggregated brain cells is juxtaposed with the tumour spheroid in order to study interaction between neoplastic and non‐neoplastic cell populations. Local invasiveness is frequently monitored by such means. Animal models of primary brain tumour suffer from a number of problems related to their biological differences with spontaneous brain tumours in man. Such animal models may be developed either by exposure to ionizing radiation, chemical carcinogens, or oncogenic viruses or by genetic manipulation. Alternatively, tumour cells or tissues may be either syngeneically transplanted into same‐species hosts or xenografted, such as when human biopsy tissue is implanted into immunologically deprived host animals. In addition to hosting primary, intrinsic brain and spinal tumours, the CNS plays host to many secondary or metastatic cancers, which originate in different, distant organs and tissues. Indeed, around a quarter of all cancers spread into the CNS, with seeding into the CNS generally bringing with it a poorer prognosis. Animal models of metastasis into the CNS are rare, as arein vitromodels. This is probably a reflection of the underinvestment of time and resources in this branch of oncology. The interaction between metastatic cancer cells and the modified blood vascular system of the brain, which incorporates the structural and physiological blood‐brain barrier (B‐BB), may be considered an interesting area for further investigation as may the direct interaction between metastatic cancer cells and the brain substance, which provides a “fertile soil” for their growth, but seems to provide a barrier to their invasive behaviour and, hence, growth is essentially proliferative in nature.
Antibody Therapy for Cancer
Authors: Wilkins Duncan K. , Begent Richard H. J.
Published: October 2007

Monoclonal antibodies (mAbs) are being explored as an anticancer therapy of growing importance and formidable potential. The exquisite specificity of antibodies provides an ideal mechanism for targeted cancer therapy. Using hybridoma technology, antibody libraries, or transgenic mice, high‐affinity antibodies can be generated against an extensive range of targets. Recombinant technology is enabling the production of fully human mAbs, smaller mAb‐based molecules, and multifunctional fusion proteins. mAbs can target a growth factor or its receptor, initiate an immunological assault, activate apoptosis, or deliver a cytotoxic payload such as a radioisotope. Several antibody‐based therapies are now licensed to treat haematological or solid tumour malignancies. This chapter explores the structure and function of antibodies, the application of recombinant technology to mAbs and the therapeutic effects of mAbs on cancer.
Cancer Chemoprevention
Authors: Kim Edward S. , Lippman Scott M.
Published: October 2007

Chemoprevention—the use of natural or synthetic chemical agents to reverse, suppress, or prevent progression to invasive cancer—is a major approach comprising laboratory and clinical research and practice for improving control of the worldwide epidemic of cancer. Chemoprevention is based on the concepts of field “cancerization” (cancer can develop in multiple foci within a field (e.g., the lung) exposed to a carcinogen (e.g., cigarette smoke)) and multistep carcinogenesis (the stepwise accumulation of genotypic and phenotypic alterations progressing through premalignant stages to cancer). Biomarkers are essential to chemoprevention research (e.g., as molecular targets for identifying new agents, markers of cancer risk for selecting trial patients, and endpoints of phase II trials). Major sites of clinical/translational chemoprevention include the lung, head and neck, breast, prostate, colorectal region, and cervix. Important clinical outcomes and advances include reducing the risks of breast cancer with tamoxifen and raloxifene, prostate cancer with finasteride, cervical intraepithelial neoplasia with HPV vaccine, and familial adenomatous polyposis with celecoxib. Major current and/or future directions of chemoprevention include molecular‐targeted research, novel imaging and other technologies aimed at developing personalized chemoprevention, and convergent development of molecular‐targeted drugs for preventing and treating precancer and cancer.
Rational Drug Design of Small Molecule Anticancer Agents: Preclinical Discovery
Authors: Collins Ian , Molife Rhoda , Kaye Stan B. , Workman Paul
Published: October 2007

In this chapter we review the development of small molecule inhibitors that act on targets involved in the causation and progression of human cancer. Considerable success has been achieved with drugs like imatinib and erlotinib that demonstrate the clinical utility of the molecular targeted approach. However, the success rate for cancer drugs in clinical development is only 1 in 20. We review the technologies that are being implemented to improve the success rate and increase the speed of preclinical oncology drug development. Topics covered include the selection and validation of drug targets, with emphasis on the genetics and biology of the disease, as well as on “druggability”; the generation of chemical “leads”, including various high‐throughput screening approaches; the use of structure‐based drug design, particularly using X‐ray crystallography; the value of chemical biology approaches; and the importance of biomarkers for patient selection and rational drug development. The integrated use of these technologies is illustrated using selected case histories. The chapter concludes with a look into the future and an assessment of the likely progress towards the development of bespoke cancer medicine. This chapter is followed by a companion chapter in which we review the clinical development of targeted molecular therapeutics.
Gene and Viral Therapy
Authors: Spurrell Emma L.
Published: October 2007

The aim of gene therapy is to treat cancer by the introduction of genes that will sensitize tumour cells to other therapies, replace a mutated gene with a wild‐type copy, or activate an antitumour host immune response. Viruses can be used as vectors for carrying therapeutic transgenes, as well as being oncolytic in their own right. Using viruses to treat tumours derives from the inherent ability of a replicating virus to eventually destroy its host cell. Oncolytic viruses are tumour specific, causing lysis of tumour cells and not normal cells. There are viruses that are naturally tumour specific and viruses that have been engineered to become tumour specific. More recently, there has been increasing interest in the development of non‐viral vectors as gene therapy carriers. The benefits of using non‐viral vectors is that they are less likely to elicit an unwanted immune response, there is no risk of recombination, and they are easier to produce on a large scale. There are two main types of non‐viral gene delivery method—physical and via a chemical carrier. Both viral and non‐viral vectors have entered human phase I and II clinical trials in patients with a variety of solid tumour malignancies.
Blood and Bone Marrow: Myeloid Leukaemias and Related Neoplasms
Authors: Chang Karen L. , Weiss Lawrence M.
Published: October 2007

Myeloid malignancies represent one category of neoplastic proliferations of cells of the hematopoietic lineage. Knowledge of the normal myeloid ontogeny helps one to understand the numerous different types of myeloid malignancies.
Finite Element Methods for Elasticity with Error‐controlled Discretization and Model Adaptivity
Authors: Stein Erwin , Rüter Marcus
Published: October 2007

The essential topics of the finite element method (FEM) for linear and finite elastic deformations of solids are presented in this chapter from both the mechanical and mathematical points of view.

As a starting point, the nonlinear and linearized theory of elasticity are derived in a rigorous way, followed by the classical variational principles of elasticity, which are the basis for the FEM in its various forms. More precisely, the discrete variational approach of the (one‐field) Dirichlet minimization principle of the total potential energy is presented, followed by concise representations of the (two‐field) Hellinger–Reissner stationary dual‐mixed principle and the (three‐field) Hu–Washizu stationary mixed principle, including the main features of the associated FEMs.

The main objective of this chapter is the systematic treatment of error estimation procedures and adaptivity for the linearized and finite elasticity problem covering both global and goal‐oriented a posteriori error estimators. The three basic classes, that is, residual‐, hierarchical‐, and averaging‐type error estimators are presented and applied to a fracture mechanics problem as an example.

A further challenging topic is the combination of error‐controlled adaptive finite element solutions with hierarchical model and dimension adaptivity of the underlying mathematical model, especially for thin‐walled structures where model expansion is necessary in subdomains with boundary layers and other disturbances.
Advanced dental maturation in New Zealand Maori and Pacific Island children
Authors: Te Moananui Raymond , Kieser Jules A. , Herbison Peter , Liversidge Helen M.
Published: October 2007

This study employs Demirjian's (1994: CD Rom. Norwood, MA: Silver Platter Education) method for assessing dental maturation to compare the rates of development in children of three ethnic populations living in New Zealand—Maori, Pacific Island, and European. We test the hypothesis that Maori and Pacific Island children will have significantly advanced dental maturation compared with New Zealand children of European extraction. The study population consists of orthopantomographs of 1,343 children (623 females and 660 males) between the ages of 2.5 and 14 years, and involves three ethnic groups—Maori, European, and Pacific Islander. Bland/Altman plots for the mean chronological age against the age difference suggest that dental age as determined by the Demirjian method is consistently lower than the chronological age of the children examined. A mixed model regression analysis shows that this difference between dental and chronological age is significantly greater in Maori than in European children (regression coefficient = 0.414; z = 7.01; P < 0.001) and also significantly greater in Pacific Island children than European children (regression coefficient = 0.574; z = 6.25; P < 0.001). Regression analysis shows that the 50th quantile maturity score of boys and girls differs by 1.49 (t = −6.18, P < 0.01) and the interaction of sex and age is also significantly different (t = −2.44, P < 0.01). Similarly, Maori girls show a difference in maturity score of 1.28 (t = −3.77, P < 0.01). However, the slopes for Maori boys and girls did not differ significantly (age/sex interaction, t = −1.25, P = 0.212). We conclude that Pacific Island children are advanced in dental maturity compared with Maori children who in turn are more advanced than New Zealand children of European origin. Am. J. Hum. Biol., 2008. © 2007 Wiley‐Liss, Inc.
Fourier transform infrared spectroscopy in the study of the interaction between PVC and plasticizers: PVC/plasticizer compatibility
Authors: González N. , Fernández‐Berridi M. J.
Published: October 2007

The interactions between Poly(vinyl chloride) (PVC) and Plasticizers, responsible for polymer plasticization, can be detected by means of Fourier transform infrared spectroscopy (FTIR). The interaction capacity between the two components depends on plasticizer chemical nature, PVC stereoregularity, and plasticizer content. In the case of ternary systems, consisting in PVC and two different plasticizers, their interaction with PVC depends essentially on their chemical nature. In this work, FTIR spectroscopy is applied to determine the effect of the cited factors on the compatibility between plasticizer and resin. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2008
Synthesis and mesomorphic properties of cholesteric elastomers based on chiral mesogenic crosslinking agent
Authors: Hu Jian‐She , Li Hao , Liu Cong , Zhang Bao‐Yan , Li Yan‐Xiang
Published: October 2007

Six chiral monomers (M1−M6), and their corresponding polymers (P1, P4) and elastomers (P2, P3, P5, P6) derived from chiral mesogenic crosslinking agent were synthesized. The chemical structures of M1−M6 were confirmed by FTIR and 1H NMR spectroscopy. The structure‐property relationships of M1−M6 and P1−P6 were discussed. Their mesomorphic properties and phase behavior were investigated by differential scanning calorimetry (DSC), thermogravimetric analyses (TGA), polarizing optical microscopy (POM), and X‐ray diffractometer (XRD) measurements. All monomers obtained, except M2 and M5, showed typical oily streaks texture and focal conic texture of cholesteric phase on heating and cooling cycles. The selective reflection of cholesteric monomers and elastomers shifted to the short wavelength region with increasing temperature. The elastomers P2 and P5 did not reveal the mesomorphic properties, and P3 and P6 showed cholesteric phase. TGA showed that P1−P6 had a high thermal stability. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2008
Mechanical and gas permeation properties of compatibilized polypropylene–layered silicate nanocomposites
Authors: Mittal Vikas
Published: October 2007

Nanocomposites of polypropylene with montmorillonite modified with dimethyldioctadecylammonium ions were prepared and the effect of compatibilizers on the mechanical and permeation properties was investigated. Compatibilizers were selected on the basis of their chemical nature, molecular weight, amount of grafting and location of the polar groups. Addition of small amount of compatibilizers led to improvements in the basal spacings of clay platelets indicating enhanced exfoliation. The modulus of the composites increased as compared with the values without compatibilizer. The oxygen permeation through the composite films either increased or remained unaffected due to possible interfacial free volume enhancement owing to the incompatibility of the surface modification and the compatibilizer. Increasing the amount of compatibilizer also increased correspondingly the extent of exfoliation. The modulus reached a plateau value after which the increasing compatibilizer led to its decrease. The gas permeation through the composite films remained unchanged with increase in the amount of compatibilizer owing to a possible balance between the decrease in permeation due to path tortuity and exfoliation and increase in permeation due to interfacial incompatibility. The improving exfoliation improved the yield and break stress indicating that the absence of tactoids can hinder the premature failure owing to better stress transfer. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2008
Dimethylsilylbis(1‐indenyl) zirconium dichloride/methylaluminoxane catalyst supported on nanosized silica for propylene polymerization
Authors: Li Kuo‐Tseng , Ko Fu‐Sheng
Published: October 2007

A dimethylsilylene‐bridged metallocene complex, (CH3)2Si(Ind)2ZrCl2, was supported on a nanosized silica particle, whose surface area was mostly external. The resulting catalyst was used to catalyze the polymerization of propylene to polypropylene. Under identical reaction conditions, a nanosized catalyst exhibited much better polymerization activity than a microsized catalyst. At the optimum polymerization temperature of 55°C, the former had 80% higher activity than the latter. In addition, the nanosized catalyst produced a polymer with a greater molecular weight, a narrower molecular weight distribution, and a higher melting point in comparison with the microsized catalyst. The nanosized catalyst's superiority was ascribed to the higher monomer concentration at its external active sites (which were free from internal diffusion resistance) and was also attributed to its much larger surface area. Electron microscopy results showed that the nanosized catalyst produced polymer particles of similar sizes and shapes, indicating that each nanosized catalyst particle had uniform polymerization activity. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2008
Some aspects of the mechanical response of BMI 5250‐4 neat resin at 191°C: Experiment and modeling
Authors: Ruggles‐Wrenn M. B. , Balaconis J. G.
Published: October 2007

The inelastic deformation behavior of BMI‐5250‐4 neat resin, a high‐temperature polymer, was investigated at 191°C. The effects of loading rate on monotonic stress–strain behavior as well as the effect of prior stress rate on creep behavior were explored. Positive nonlinear rate sensitivity was observed in monotonic loading. Creep response was found to be significantly influenced by prior stress rate. Effect of loading history on creep was studied in stepwise creep tests, where specimens were subjected to a constant stress rate loading followed by unloading to zero stress with intermittent creep periods during both loading and unloading. The strain‐time behavior was strongly influenced by prior deformation history. Negative creep was observed on the unloading path. In addition, the behavior of the material was characterized in terms of a nonlinear viscoelastic model by means of creep and recovery tests at 191°C. The model was employed to predict the response of the material under monotonic loading/unloading and multi‐step load histories. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2008
Elastic properties of cast films from propylene elastomers
Authors: Tsou Andy H. , Lyon Michael K. , Chapman Bryan R. , Datta Sudhin
Published: October 2007

Propylene‐rich ethylene–propylene copolymers (P‐E elastomers) made using metallocene catalysts exhibit excellent elastic properties, including high elongation to break and low tension set, particularly when blended with polyethylene or polypropylene and then compression molded. During film casting, the orientation imposed on a P‐E elastomer lowers the extensibility and elastic recovery of films prepared from either neat P‐E or P‐E blends. A reduction in elongation to break of P‐E films, with or without blending, was found to correlate with an increase in planar birefringence. The presence of dispersed phases of PP or high density polyethylene in P‐E blends, which are drawn into elongated ellipsoids aligned in the machine direction, further reduces the recovery of these P‐E blends. This reduction in elastic recovery for films made from P‐E blends with aligned ellipsoidal dispersions was attributed to strain amplification around the dispersed particles in accordance with finite element simulation results, and was directly related to the dispersion tip radius. Films from P‐E elastomer blended with high density polyethylene (high interfacial tension) were demonstrated to have lower planar orientation in addition to reduced dispersion deformation, and, therefore, better elastic properties, versus films in which the P‐E elastomer was blended with PP (low interfacial tension). © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2008
Hyperbranched polyesters with internal and exo‐presented hydrogen‐bond acidic sensor groups for surface acoustic wave sensors
Authors: Hartmann‐Thompson Claire , Keeley Douglas L. , Voit Brigitte , Eichhorn Klaus‐J. , Mikhaylova Yulia
Published: October 2007

Three hyperbranched aromatic polyesters carrying both internal and exo‐presented hydrogen‐bond acidic phenol, carboxylic acid, or mixed phenol/acetoxy groups were coated onto 500 MHz surface acoustic wave (SAW) sensor platforms, and sensor responses to the nerve agent simulant dimethyl methylphosphonate (DMMP) and the explosives simulant dinitrotoluene (DNT) were studied. All three hyperbranched polyesters gave strong responses to DMMP, and the hyperbranched polyester carrying carboxylic acid groups gave a particularly strong response. The hyperbranched polyester carrying phenol groups gave the best response to DNT of the three polymers studied. The DMMP and DNT responses of the three hyperbranched polyesters were also compared with hyperbranched SAW sensor polymers carrying exo‐presented phenolic sensor groups only, and also with linear SAW sensor polymers carrying phenolic sensor groups. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2008
Reconstruction and Morphometric Analysis of the Nasal Airway of the Dog (Canis familiaris) and Implications Regarding Olfactory Airflow
Authors: Craven Brent A. , Neuberger Thomas , Paterson Eric G. , Webb Andrew G. , Josephson Eleanor M. , Morrison Edward E. , Settles Gary S.
Published: October 2007

The canine nasal airway is an impressively complex anatomical structure, having many functional roles. The complicated branching and intricate scrollwork of the nasal conchae provide large surface area for heat, moisture, and odorant transfer. Of the previous anatomical studies of the canine nasal airway, none have included a detailed rendering of the maxilloturbinate and ethmoidal regions of the nose. Here, we present a high‐resolution view of the nasal airway of a large dog, using magnetic resonance imaging scans. Representative airway sections are shown, and a three‐dimensional surface model of the airway is reconstructed from the image data. The resulting anatomic structure and detailed morphometric data of the airway provide insight into the functional nature of canine olfaction. A complex airway network is revealed, wherein the branched maxilloturbinate and ethmoturbinate scrolls appear structurally distinct. This is quantitatively confirmed by considering the fractal dimension of each airway, which shows that the maxilloturbinate airways are more highly contorted than the ethmoidal airways. Furthermore, surface areas of the maxilloturbinate and ethmoidal airways are shown to be much different, despite having analogous physiological functions. Functionally, the dorsal meatus of the canine nasal airway is shown to be a bypass for odorant‐bearing inspired air around the complicated maxilloturbinate during sniffing for olfaction. Finally, nondimensional analysis is used to show that the airflow within both the maxilloturbinate and ethmoturbinate regions must be laminar. This work has direct relevance to biomimetic sniffer design, chemical trace detector development, intranasal drug delivery, and inhalation toxicology. Anat Rec, 290:1325–1340, 2007. © 2007 Wiley‐Liss, Inc.
Light Microscopic and Ultrastructural Observations on the Vomeronasal Organ of Anoura (Chiroptera: Phyllostomidae)
Authors: Bhatnagar Kunwar P. , Smith Timothy D.
Published: October 2007

The vomeronasal organ (VNO) is known to be present in bats of the family Phyllostomidae, but in most species this is inferred from the presence of accessory olfactory bulbs. Like primates, bats have profound intergroup variations in the vomeronasal system. Of the family Phyllostomidae (49 genera, 143 species) the VNO of approximately 60 species has been studied. Here, we report light microscopic observations of the VNO of Anoura geoffroyi (fetus and adult), A. caudifer, and A. cultrata, as well as ultrastructural observations of the VNO in adult A. geoffroyi. The organ is crescent‐shaped, with a wide lumen encroached by a “mushroom body” that contains a venous sinus. In adults, the vomeronasal cartilage is reduced, being longer in absolute length in fetal A. geoffroyi compared with the adult. In the neuroepithelium, the receptor cell microvilli are dark, distinct, and short, emerging from a vesicular tuft; the supporting cell microvilli are relatively much longer. Large paravomeronasal ganglia are observed. The receptor‐free epithelium is undulating and lacks cilia or microvilli. Some characteristics of the VNO in Anoura have not been reported in other chiropterans to date, such as the marked reduction of the vomeronasal cartilage and absence of cilia in the receptor‐free epithelium. Moreover, if A. geoffroyi is representative, the genus has an adult neuroepithelial volume similar to other mammals of its body size. Further examination of uninvestigated phyllostomid VNOs may elucidate a phylogenetic history of the family, as well as ecological or social correlates of the VNO in the order Chiroptera. Anat Rec 290:1341–1354, 2007. © 2007 Wiley‐Liss, Inc.
Statistical Analysis of the Angle of Intrusion of Porcine Ventricular Myocytes from Epicardium to Endocardium Using Diffusion Tensor Magnetic Resonance Imaging
Authors: Schmid Peter , Lunkenheimer Paul P. , Redmann Klaus , Rothaus Kai , Jiang Xiaoyi , Cryer Colin W. , Jaermann Thomas , Niederer Peter , Boesiger Peter , Anderson Robert H.
Published: October 2007

Pairs of cylindrical knives were used to punch semicircular slices from the left basal, sub‐basal, equatorial, and apical ventricular wall of porcine hearts. The sections extended from the epicardium to the endocardium. Their semicircular shape compensated for the depth‐related changing orientation of the myocytes relative to the equatorial plane. The slices were analyzed by diffusion tensor magnetic resonance imaging. The primary eigenvector of the diffusion tensor was determined in each pixel to calculate the number and angle of intrusion of the long axis of the aggregated myocytes relative to the epicardial surface. Arrays of axially sectioned aggregates were found in which 53% of the approximately two million segments evaluated intruded up to ±15°, 40% exhibited an angle of intrusion between ±15° and ±45°, and 7% exceeded an angle of ±45°, the positive sign thereby denoting an epi‐ to endocardial spiral in clockwise direction seen from the apex, while a negative sign denotes an anticlockwise spiral from the epicardium to the endocardium. In the basal and apical slices, the greater number of segments intruded in positive direction, while in the sub‐basal and equatorial slices, negative angles of intrusion prevailed. The sampling of the primary eigenvectors was insensitive to postmortem decomposition of the tissue. In a previous histological study, we also documented the presence of large numbers of myocytes aggregated with their long axis intruding obliquely from the epicardial to the endocardial ventricular surfaces. We used magnetic resonance diffusion tensor imaging in this study to provide a comprehensive statistical analysis. Anat Rec, 290:1413–1423, 2007. © 2007 Wiley‐Liss, Inc.
Relevance: A review of the literature and a framework for thinking on the notion in information science. Part II: nature and manifestations of relevance
Authors: Saracevic Tefko
Published: October 2007

Relevant: Having significant and demonstrable bearing on the matter at hand.*

A version of this article has been published in 2006 as a chapter in E.G. Abels & D.A. Nitecki (Eds.), Advances in Librarianship (Vol. 30, pp. 3–71). San Diego: Academic Press. (Saracevic, 2006).

Relevance: The ability as of an information retrieval system to retrieve material that satisfies the needs of the user.

—Merriam‐Webster Dictionary 2005

Relevance is a, if not even the, key notion in information science in general and information retrieval in particular. This two‐part critical review traces and synthesizes the scholarship on relevance over the past 30 years and provides an updated framework within which the still widely dissonant ideas and works about relevance might be interpreted and related. It is a continuation and update of a similar review that appeared in 1975 under the same title, considered here as being Part I. The present review is organized into two parts: Part II addresses the questions related to nature and manifestations of relevance, and Part III addresses questions related to relevance behavior and effects. In Part II, the nature of relevance is discussed in terms of meaning ascribed to relevance, theories used or proposed, and models that have been developed. The manifestations of relevance are classified as to several kinds of relevance that form an interdependent system of relevances. In Part III, relevance behavior and effects are synthesized using experimental and observational works that incorporate data. In both parts, each section concludes with a summary that in effect provides an interpretation and synthesis of contemporary thinking on the topic treated or suggests hypotheses for future research. Analyses of some of the major trends that shape relevance work are offered in conclusions.
Knowledge sharing in online environments: A qualitative case study
Authors: Hew Khe Foon , Hara Noriko
Published: October 2007

This study expands the perspective of knowledge sharing by categorizing the different types of knowledge that individuals shared with one another and examining the patterns of motivators and barriers of knowledge sharing across three online environments pertaining to the following professional practices—advanced nursing practice, Web development, and literacy education. The patterns indicate the different possible combinations of motivators or barriers that may exist in individuals. Data were gathered through online observations and semistructured interviews with 54 participants. The cross‐case analysis shows that the most common type of knowledge shared across all three environments was practical knowledge. Overall, seven motivators were found. Analysis also suggests that the most common combination of motivators for knowledge sharing was collectivism and reciprocity. A total of eight barriers were identified. The most common combination of barriers varied in each online environment. Discussions as to how the types of professional practices may contribute to the different results are provided, along with implications and future possible research directions.
Ontology‐supported polarity mining
Authors: Zhou Lina , Chaovalit Pimwadee
Published: October 2007

Polarity mining provides an in‐depth analysis of semantic orientations of text information. Motivated by its success in the area of topic mining, we propose an ontology‐supported polarity mining (OSPM) approach. The approach aims to enhance polarity mining with ontology by providing detailed topic‐specific information. OSPM was evaluated in the movie review domain using both supervised and unsupervised techniques. Results revealed that OSPM outperformed the baseline method without ontology support. The findings of this study not only advance the state of polarity mining research but also shed light on future research directions.
O‐Alkyl S‐3,3‐Dimethyl‐2‐oxobutyl Dithiocarbonates as Versatile Sulfur‐Transfer Agents in Radical C(sp3)H Functionalization
Authors: Sato Akinori , Yorimitsu Hideki , Oshima Koichiro
Published: October 2007

Boiling of the title compounds in ethereal solvents or cycloalkanes in the presence of a radical initiator leads to radical C(sp3)H functionalization, by which a sulfur atom is introduced into the ethereal solvents at the oxygenated carbon atom or into the cycloalkanes. Both acyclic and cyclic ethers, such as [18]crown‐6 and [D8]THF, undergo the sulfur transfer. The reaction is useful for the synthesis of monothioacetals, thiols, and sulfides from simple starting materials.
Exposure to extremely low frequency magnetic fields affects insulin‐secreting cells
Authors: Sakurai Tomonori , Yoshimoto Miwa , Koyama Shin , Miyakoshi Junji
Published: October 2007

To evaluate the effects of extremely low frequency magnetic field (ELFMF) on β‐cell survival and function, we cultured a hamster‐derived insulin‐secreting cell line (HIT‐T15), which exhibits responsiveness to glucose in a semi‐physiological range, under exposure to sham and ELFMF conditions, and assessed cell survival and function. We used our previously developed ELFMF exposure unit (a sinusoidal magnetic field at a frequency of 60 Hz, 5 mT) to culture cells under exposure to ELFMF conditions. We found that exposure to ELFMF for 5 days in the absence of glucose increased cell number, exposure for 2 days in the absence of glucose and for 5 days with 100 mg/dl glucose increased the insulin secretion to the culture medium, and exposure for 2 and 5 days with 40 and 100 mg/dl glucose increased intracellular insulin concentration in HIT‐T15 cells. The increase in cell number under apoptotic culture conditions by exposure to ELFMF could lead to new therapeutic concepts in the treatment of diabetes. The ELFMF‐induced increase in intracellular insulin concentration could be utilized to develop culture conditions to enhance intracellular insulin concentration in insulin‐secreting cells that would be useful for cell transplantation to cure diabetes mellitus. Bioelectromagnetics 29:118–124, 2008. © 2007 Wiley‐Liss, Inc.
Electromagnetic field measurements using personal exposimeters
Authors: Knafl Urs , Lehmann Hugo , Riederer Markus
Published: October 2007

The goal of this brief communication is to call the attention of researchers to possible pit falls when using personal exposimeters (PEM) in epidemiological field studies. One example of problematic handling of PEMs is presented in detail, whereas other possible error sources and other aspects to be considered using such devices are outlined only briefly. Bioelectromagnetics 29:160–162, 2008. © 2007 Wiley‐Liss, Inc.
Fate of the non-operated, non-toxic goitre in a defined population
Authors: Winbladh A , Järhult J
Published: October 2007

Background

There is lack of consensus in Europe regarding the management of patients with benign goitre. This study evaluated the long-term results of recommending no surgery for clinically and cytologically benign goitre.

Methods

Some 261 patients (median age 56 years) referred for surgical evaluation for goitre were followed prospectively for a median of 130 months. All hospital and primary care charts were reviewed and living patients interviewed by telephone.

Results

During follow-up, 36·4 per cent of patients were re-referred for a new surgical evaluation, mainly because of growth of the goitre and/or worsening of local symptoms. Fifty-seven (21·8 per cent) of the patients had surgery, and 13 developed thyrotoxicosis. Five patients (1·9 per cent) were diagnosed with thyroid carcinoma, three of whom (all elderly women) died from the disease. Some 95·0 per cent of patients were satisfied with the expectant policy, but 13·1 per cent had been worried about thyroid cancer despite the reassurance of a benign diagnosis.

Conclusion

Patients with benign goitre can be treated conservatively with good results. However, there is a small risk that aggressive carcinoma will develop and about a quarter of patients may need surgery within 10 years of the decision to wait and see.
Face‐to‐Face Pacman‐Type Porphyrin–Fullerene Dyads: Design, Synthesis, Charge‐Transfer Interactions, and Photophysical Studies
Authors: D'Souza Francis , Maligaspe Eranda , Karr Paul A. , Schumacher Amy Lea , El Ojaimi Maya , Gros Claude P. , Barbe Jean‐Michel , Ohkubo Kei , Fukuzumi Shunichi
Published: October 2007

Pacman‐type face‐to‐face zinc–porphyrin–fullerene dyads have been newly synthesized and studied. Owing to the close proximity of the donor and acceptor entities, strong π–π intramolecular interactions between the porphyrin and fullerene entities resulted in modulating the spectral and electrochemical properties of the dyads. New absorption and emission bands that correspond to the charge‐transfer interactions were observed in the near‐IR region. Time‐resolved transient absorption studies revealed efficient photoinduced electron transfer from the singlet excited porphyrin to the fullerene entity. The rate constants for photoinduced electron transfer are analyzed in terms of the Marcus theory of electron transfer, which afforded a large electron coupling matrix element (V=140 cm−1) for the face‐to‐face dyads. As a consequence of the large charge‐recombination driving force in the Marcus inverted region, a relatively long lifetime of the charge‐separated state has been achieved.
Structure and Vibrational Spectra of Ti(IV) Hydroxides and Their Clusters with Expanded Titanium Coordination. DFT Study.
Authors: Ignatyev Igor S. , Montejo Manuel , Gonzalez Juan Jesus Lopez
Published: October 2007

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Revisiting the Sr—Cr(IV)—O System at High Pressure and Temperature with Special Reference to Sr3Cr2O7.
Authors: Castillo‐Martinez Elizabeth , Alario‐Franco Miguel Angel
Published: October 2007

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
195Pt NMR Chemical Shift Trend Analysis as a Method to Assign New Pt(IV)—Halohydroxo Complexes.
Authors: Kramer Jurjen , Koch Klaus R.
Published: October 2007

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Heats of Formation of Boron Hydride Anions and Dianions and Their Ammonium Salts [BnHmy‐] [NH4+]y with y = 1—2
Authors: Nguyen Minh Tho , Matus Myrna H. , Dixon David A.
Published: October 2007

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Structure and Oxygen Storage Capacity of Pr/Nd Doped CeO2—ZrO2 Mixed Oxides.
Authors: Wu Xiaodi , Wu Xiaodong , Liang Qing , Fan Jun , Weng Duan , Xie Zhi , Wei Shiqiang
Published: October 2007

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
VIIIV3IVO3 (PO4)3: A Novel Vanadium Phosphate for Selective Oxidation of Light Hydrocarbons.
Authors: Benser Ernst , Glaum Robert , Dross Thomas , Hibst Hartmut
Published: October 2007

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
The Heteropolytungstate Core {BW13O46}11‐ Derived as Monomer, Dimer, and Trimer.
Authors: Leclerc‐Laronze Nathalie , Marrot Jerome , Herve Gilbert , Thouvenot Rene , Cadot Emmanuel
Published: October 2007

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Crystal Growth and Magnetic Properties of the New Iridates Ln1‐xNa1+xIrO4 (Ln: Gd—Er, Y; x = 0.04—0.25).
Authors: Mugavero Samuel J. III , Smith Mark D. , zur Loye Hans‐Conrad
Published: October 2007

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Substitution of Acyl for Acetyl with N‐Acylbenzotriazoles Catalyzed by Samarium Triiodide.
Authors: Zou Xuefei , Jia Xiaofei , Wang Xiaoxia , Xie Guanqun
Published: October 2007

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Microwave Assisted Diels—Alder Cycloaddition of 2‐Fluoro‐3‐methoxy‐1,3‐butadiene.
Authors: Patrick Timothy B. , Gorrell Keith , Rogers James
Published: October 2007

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
[(NHC)AuI]‐Catalyzed Rearrangement of Allylic Acetates.
Authors: Marion Nicolas , Gealageas Ronan , Nolan Steven P.
Published: October 2007

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Paracyclophanes. Part 58. The Use of the Stilbene‐Phenanthrene Photocyclization in [2.2]Paracyclophane Chemistry.
Authors: Hopf H. , Hucker J. , Ernst L.
Published: October 2007

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Aerobic Ruthenium‐Catalyzed Oxidative Transformation of Secondary Amines to Imines.
Authors: Murahashi Shun‐Ichi , Okano Yuriko , Sato Hideomi , Nakae Takahiro , Komiya Naruyoshi
Published: October 2007

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Pd/C(en) Catalyzed Chemoselective Hydrogenation in the Presence of Aryl Nitriles.
Authors: Maegawa Tomohiro , Fujita Yuki , Sakurai Ai , Akashi Akira , Sato Mutsumi , Oono Keiji , Sajiki Hironao
Published: October 2007

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Silver‐Catalyzed Intermolecular Amination of C—H Groups.
Authors: Li Zigang , Capretto D. A. , Rahaman R. , He Chuan
Published: October 2007

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Reactions of Ethyl Triphenylphosphoranylideneacetate with Fluorinated β‐Ketoaldehyde Derivatives.
Authors: Kondratov Ivan S. , Gerus Igor I. , Furmanova Marina V. , Vdovenko Sergey I. , Kukhar Valery P.
Published: October 2007

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Small‐Molecule N‐Heterocyclic‐Carbene‐Containing Olefin‐Metathesis Catalysts for Use in Water.
Authors: Jordan Jason P. , Grubbs Robert H.
Published: October 2007

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Formate as a CO Surrogate for Cascade Processes: Rh‐Catalyzed Cooperative Decarbonylation and Asymmetric Pauson—Khand‐Type Cyclization Reactions.
Authors: Lee Hang Wai , Chan Albert S. C. , Kwong Fuk Yee
Published: October 2007

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Pd(0) Catalyzed Three—Five‐Component C‐2‐Arylallylation of Active Methylene Heterocycles: Pyrazolones, Oxazolones, Isoxazolones and N,N′‐Dimethylbarbituric Acid.
Authors: Grigg Ronald , Sarkar M. Ruhul A. , Thayaparan Abirami , Sridharan Visuvanathar , Fishwick Colin W. G.
Published: October 2007

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Base‐Catalyzed anti‐Markovnikov Hydroamination of Vinylarenes — Scope, Limitations and Computational Studies.
Authors: Horillo‐Martinez Patricia , Hultzsch Kai C. , Gil Adria , Branchadell Vicenc
Published: October 2007

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
An Approach to Amino Ester Subunits of Tamiflu.
Authors: Kraus George A. , Goronga Tinopiwa
Published: October 2007

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Asymmetric Organocatalytic Domino Reactions of γ‐Nitroketones and Enals.
Authors: Enders Dieter , Narine Arun A. , Benninghaus Thomas R. , Raabe Gerhard
Published: October 2007

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Gold‐Catalyzed Cyclizations of 1,7‐Enynes.
Authors: Cabello Noemi , Rodriguez Cristina , Echavarren Antonio M.
Published: October 2007

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Azulene Derivatives Soluble in Polar Solvents. 1‐(Azulen‐1‐yl)‐2‐(thien‐2‐ or 3‐yl)‐ethenes.
Authors: Razus Alexandru C. , Birzan Liviu , Tecuceanu Victorita , Cristea Mihaela , Nicolescu Alina , Enache Cristian
Published: October 2007

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Enantiospecific Synthesis of 1,3‐Disubstituted Allenes by Palladium‐Catalyzed Coupling of Propargylic Compounds with Arylboronic Acids.
Authors: Yoshida Masahiro , Okada Tatsuro , Shishido Kozo
Published: October 2007

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Preparation of 1‐Aryl‐2,2‐difluoro Enol Esters via Dehydrosulfonylation of α‐(Phenylsulfonyl)difluoromethylated Benzoates.
Authors: Zhang Laijun , Li Ya , Hu Jinbo
Published: October 2007

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Reversible C—F Bond Formation and the Au‐Catalyzed Hydrofluorination of Alkynes.
Authors: Akana Jennifer A. , Bhattacharyya Koyel X. , Mueller Peter , Sadighi Joseph P.
Published: October 2007

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Effective Monoallylation of Anilines Catalyzed by Supported KF.
Authors: Pace Vittorio , Martinez Fernando , Fernandez Maria , Sinisterra Jose V. , Alcantara Andres R.
Published: October 2007

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Facile Synthesis of 9‐Azajulolidine and Its Application to post‐Ullmann Reactions.
Authors: Wong Ken‐Tsung , Ku Sung‐Yu , Yen Feng‐Wen
Published: October 2007

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Preparation of New C2‐Symmetric Tetraphosphine Ligands for Rh‐Catalyzed Asymmetric Hydrogenation of Arylenamides.
Authors: Zhao Dongbo , Wang Zheng , Ding Kuiling
Published: October 2007

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.