bluuebunny/crossref_metadata_2025 huggingface dataset:
The action of pulse‐modulated GSM radiation increases regional changes in brain activity and c‐Fos expression in cortical and subcortical areas in a rat model of picrotoxin‐induced seizure proneness
Authors: López‐Martín E. , Bregains J. , Relova‐Quinteiro J.L. , Cadarso‐Suárez C. , Jorge‐Barreiro F.J. , Ares‐Pena F.J.
Published: December 2008

The action of the pulse‐modulated GSM radiofrequency of mobile phones has been suggested as a physical phenomenon that might have biological effects on the mammalian central nervous system. In the present study, GSM‐exposed picrotoxin‐pretreated rats showed differences in clinical and EEG signs, and in c‐Fos expression in the brain, with respect to picrotoxin‐treated rats exposed to an equivalent dose of unmodulated radiation. Neither radiation treatment caused tissue heating, so thermal effects can be ruled out. The most marked effects of GSM radiation on c‐Fos expression in picrotoxin‐treated rats were observed in limbic structures, olfactory cortex areas and subcortical areas, the dentate gyrus, and the central lateral nucleus of the thalamic intralaminar nucleus group. Nonpicrotoxin‐treated animals exposed to unmodulated radiation showed the highest levels of neuronal c‐Fos expression in cortical areas. These results suggest a specific effect of the pulse modulation of GSM radiation on brain activity of a picrotoxin‐induced seizure‐proneness rat model and indicate that this mobile‐phone‐type radiation might induce regional changes in previous preexcitability conditions of neuronal activation. © 2008 Wiley‐Liss, Inc.
Peripheral challenge with double‐stranded RNA elicits global up‐regulation of cytokine gene expression in the brain
Authors: Konat Gregory W. , Borysiewicz Elizabeth , Fil Daniel , James Isaac
Published: December 2008

It is well established that mediators of peripheral inflammation are relayed to the brain and elicit sickness behavior via neuroinflammatory agents that target neuronal substrates. In the present study, we used double‐stranded RNA (dsRNA), a viral replication intermediate, to mimic the acute phase of viral infection. C57BL/6 mice were injected intraperitoneally with 12 mg/kg of synthetic dsRNA, i.e., polyinosinic‐polycytidylic acid (PIC). The treatment induced severe sickness behavior in the animals as revealed by the burrowing test performed 6 hr postinjection. PIC challenge also induced up‐regulation of mRNA for several cytokines in the brain as determined by real‐time quantitative RT‐PCR. In all brain regions, i.e., the forebrain, brainstem, and cerebellum, the gene encoding the CXCL2 chemokine featured the most robust up‐regulation over the basal level (saline‐injected animals), followed by the genes encoding the CCL2 chemokine, interferon‐β (IFNβ), interleukin‐6 (IL‐6), tumor necrosis factor‐α (TNFα), and interleukin‐1β (IL‐1β). The forebrain featured the highest extent of up‐regulation of the Ifnb gene, whereas the other genes attained the highest expression in the cerebellum. Most of the genes featured transient up‐regulation, with peaks occurring 3–6 hr after PIC challenge. The TNFα, CCL2, CXCL2, IFNβ, and IL‐1β messages remained profoundly up‐regulated even at 24 hr. The expression of genes encoding inducible and neuronal nitric oxide synthase (NOS) in the brain was not affected by the peripheral PIC challenge. However, the endothelial NOS message was initially down‐regulated and subsequently up‐regulated, indicating stimulation of cerebral vasculature. © 2008 Wiley‐Liss, Inc.
Low‐intensity treadmill exercise‐related changes in the rat stellate ganglion neurons
Authors: Cavalcanti Renato Albuquerque de Oliveira , da Pureza Demilto Yamaguchi , de Melo Mariana Pereira , de Souza Romeu Rodrigues , Bergamaschi Cássia T. , do Amaral Sandra Lia , Tang Helen , Loesch Andrzej , Ribeiro Antonio Augusto Coppi Maciel
Published: December 2008

Stellate ganglion (SG) represents the main sympathetic input to the heart. This study aimed at investigating physical exercise–related changes in the quantitative aspects of SG neurons in treadmill‐exercised Wistar rats. By applying state‐of‐the‐art design‐based stereology, the SG volume, total number of SG neurons, mean perikaryal volume of SG neurons, and the total volume of neurons in the whole SG have been examined. Arterial pressure and heart rate were also measured at the end of the exercise period. The present study showed that a low‐intensity exercise training program caused a 12% decrease in the heart rate of trained rats. In contrast, there were no effects on systolic pressure, diastolic pressure, or mean arterial pressure. As to quantitative changes related to physical exercise, the main findings were a 21% increase in the fractional volume occupied by neurons in the SG, and an 83% increase in the mean perikaryal volume of SG neurons in treadmill‐trained rats, which shows a remarkable neuron hypertrophy. It seems reasonable to infer that neuron hypertrophy may have been the result of a functional overload imposed on the SG neurons by initial posttraining sympathetic activation. From the novel stereological data we provide, further investigations are needed to shed light on the mechanistic aspect of neuron hypertrophy: what role does neuron hypertrophy play? Could neuron hypertrophy be assigned to the functional overload induced by physical exercise? © 2008 Wiley‐Liss, Inc.
Deleterious effects of minocycline after in vivo target deprivation of thalamocortical neurons in the immature, metallothionein‐deficient mouse brain
Authors: Potter Emily G. , Cheng Ying , Natale JoAnne E.
Published: December 2008

Compared with adults, immature metallothionein I and II knockout (MT−/−) mice incur greater neuronal loss and a more rapid rate of microglia accumulation after target deprivation‐induced injury. Because minocycline has been proposed to inhibit microglial activation and associated production of neuroinflammatory factors, we investigated its ability to promote neuronal survival in the immature, metallothionein‐deficient brain. After ablation of the visual cortex, 10‐day‐old MT−/− mice were treated with minocycline or saline and killed 24 or 48 hr after injury. By means of stereological methods, the number of microglia and neurons were estimated in the ipsilateral dorsal lateral geniculate nucleus (dLGN) by an investigator blinded to the treatment. No effect on neuronal survival was observed at 24 hr, but 48 hr after injury, an unanticipated but significant minocycline‐mediated increase in neuronal loss was detected. Further, while failing to inhibit microglial accumulation, minocycline treatment increased the proportion of amoeboid microglia in the ipsilateral dLGN. To understand the molecular mechanisms underlying this neurotoxic response, we identified minocycline‐mediated changes in the expression of three potentially proapoptotic/inflammatory genes: growth arrest– and DNA damage–inducible gene 45γ (GADD45γ); interferon‐inducible protein 1 (IFI1), and cytokine‐induced growth factor. We also observed increased mitogen‐activated protein kinase p38 phosphorylation with minocycline treatment. Although minocycline inhibited calpain activity at 12 hr after injury, this effect was not sustained at 24 hr. Together, these results help to explain how minocycline has a deleterious effect on neuronal survival in this injury model. © 2008 Wiley‐Liss, Inc.
Adult stem cell therapies for neurological disorders: Benefits beyond neuronal replacement?
Authors: Boucherie Cédric , Hermans Emmanuel
Published: December 2008

The modest capacity of endogenous repair processes in the central nervous system (CNS) justifies the broad interest in the development of effective stem cell based therapies for neurodegenerative disorders and other acute or chronic lesions. Motivated by the ambitious expectation to achieve functional neuronal replacement, several studies have already evidenced a potential benefit of stem cell grafts in animal models of human disorders. Nevertheless, growing evidence suggests that the effects orchestrated by stem cells, in most experimental cases, are not necessarily associated with the generation of new neurons. This hypothesis correlates with the versatile properties of adult and embryonic stem cells. When introduced into the lesioned CNS, nondifferentiated stem cells can have a positive influence through intrinsic neuroprotective capacities related to the production of neurotrophic factors, stimulation of endogenous neurogenesis, and modulation of neuroinflammation. Stem cells are also endowed with a multipotent differentiation profile, suggesting that a positive outcome could result from the replacement of nonneuronal cell types, in particular astrocytes and oligodendrocytes. Focusing on adult stem cells, this Review aims at summarizing experimental observations supporting the concept that, in cell‐based therapies, stem cells operate not through a unidirectional mechanism (e.g., generating neurons) but rather as cellular mediators of a multitude of biological activities that could provide a favorable outcome for diverse nervous disorders. © 2008 Wiley‐Liss, Inc.
Factors associated with detection failure and false‐negative sentinel node biopsy findings in gastric cancer: Results of prospective single center trials
Authors: Lee Jun Ho , Ryu Keun Won , Nam Byung‐Ho , Kook Myeong‐Cherl , Cho Soo‐Jeong , Lee Jong Yeul , Kim Chan Gyoo , Choi Il Ju , Park Sook Ryun , Kim Young Woo
Published: December 2008

Background and Objectives

The factors associated with successful sentinel node biopsy (SNB) are limited in gastric cancer despite a wide range of sensitivities reported. This study was performed to identify the factors associated with detection failure and SNB false‐negativity in gastric cancer.

Methods

SNB was performed on 156 gastric cancer patients from May 2002 to April 2007 at the Korean National Cancer Center during three consecutive prospective trials. Indications for SNB were determined preoperatively in cT1‐2N0 patients. Dissected SNs and non‐SNs after D2 lymphadenectomy were pathologically evaluated for metastasis. Clinical, pathological, and technical factors were analyzed for detection failure and false‐negativity.

Results

SNs were detected in 147 patients (94.2%) and the median number of SNs detected per patient was 3 (1–12). Twenty‐five of 37 with nodal metastasis were diagnosed by SNB (sensitivity, 67.6%). Surgeon's inexperience (≤30 procedures) and a male patient gender were significantly associated with detection failure (P = 0.014 and 0.031, respectively). A small number of SNs (≤ 3) was found to be significantly associated with false‐negativity (P = 0.027).

Conclusions

SNB requires experience for successful detection and should be performed cautiously in male patients. Harvesting of more than three SNs is warranted to reduce false‐negatives when diagnosing nodal metastasis. J. Surg. Oncol. 2009;99: 137–142. © 2008 Wiley‐Liss, Inc.
Vascular endothelial growth factor‐C and ‐D expression correlates with lymph node micrometastasis in pN0 early gastric cancer
Authors: Arigami Takaaki , Natsugoe Shoji , Uenosono Yoshikazu , Yanagita Shigehiro , Ehi Katsuhiko , Arima Hideo , Mataki Yuko , Nakajo Akihiro , Ishigami Sumiya , Aikou Takashi
Published: December 2008

Background and Objectives

Vascular endothelial growth factors (VEGF)‐C and ‐D play an important role in lymphangiogenesis, and the expressions of these factors are related to lymphatic invasion and lymph node metastasis in various malignant neoplasms. The present study investigates the expression of VEGF‐C and ‐D in early gastric cancer and analyzes its relationship to lymph node micrometastasis determined by reverse transcription‐polymerase chain reaction (RT‐PCR).

Methods

We examined 1,828 lymph nodes obtained from 80 patients with node‐negative early gastric cancer. All dissected lymph nodes were examined by RT‐PCR for CEA mRNA in addition to hematoxylin–eosin staining. The resected primary specimens were immunostained using anti‐VEGF‐C and ‐D polyclonal antibodies.

Results

The incidence of lymph node micrometastasis determined by RT‐PCR was 23.8% (19/80). The high expression of VEGF‐C and ‐D was found in 27.5% (22/80) and in 21.3% (17/80), respectively. The expression of VEGF‐C and ‐D was closely related to lymph node micrometastasis (P = 0.0390 and 0.0213, respectively).

Conclusions

We demonstrated a close relationship between micrometastasis and VEGF‐C and ‐D expression of the primary tumor. Thus, levels of VEGF‐C and ‐D expression might be useful for predicting micrometastasis in patients with early gastric cancer. J. Surg. Oncol. 2009;99: 148–153. © 2008 Wiley‐Liss, Inc.
Behavior of Endothelial Cells Regulated by a Dynamically Changed Microenvironment of Biodegradable PLLA‐PC
Authors: Chen Yuanwei , Chen Niancao , Qiu Zhi , Wang Lijian , Wan Changxiu , Luo Xianglin , Li Suming
Published: December 2008

The influence of PLLA‐PC membranes on the behavior of vascular ECs is studied. It was found that the membranes were not cytotoxic. The cell adhesion and spread on PLLA‐PC 30/1 were initially depressed. After 1 d, however, cells attached and spread on the copolymer, and proliferated beyond 2 d. To elucidate the mechanism of this behavior, the surface morphology and the degradation products of the PLLA/PC 30/1 membrane during the culture period were tested, and Fg adsorption to the membranes was examined. It is concluded that the behavior of ECs can be regulated by a dynamically changed microenvironment of the PLLA‐PC membrane. PLLA‐PC copolymers might therefore serve as a novel material for tissue engineering.

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Influence of Molecular Weight on Physical and Mechanical Properties of Linear Symmetric S‐(S/B)‐S Triblock Copolymers
Authors: Thunga Mahendra , Staudinger Ulrike , Ganß Martin , Weidisch Roland , Knoll Konrad
Published: December 2008

Symmetric linear S‐(S/B)‐S triblock copolymers with 80 wt.‐% of PS having a block composition of 20‐60‐20 and a S/B ratio of 70:30 in the middle block are studied with varying molecular weights ($\overline M _{\rm w}$). Increase in the$\overline M _{\rm w}$leads to a change in the morphology from disordered to ordered microphase separated structure, as characterised by TEM and SAXS. Two distinct glass transitions for PS‐ and PB‐rich phases are observed from DMA measurements, which are due to phase separation at high$\overline M _{\rm w}$. Rheological studies (master curves) reveal an extended rubbery plateau and a delay in the terminal response with an increase in$\overline M _{\rm w}$, whereas a terminal flow behaviour is observed for materials having a disordered nature at low$\overline M _{\rm w}$. A brittle‐to‐tough transition is observed from tensile tests with the increase in$\overline M _{\rm w}$.

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New Block Copolymers with Poly(N,N‐dimethylaminoethyl methacrylate) as a Double Stimuli‐Responsive Block
Authors: Schacher Felix , Müllner Markus , Schmalz Holger , Müller Axel H. E.
Published: December 2008

The synthesis of several diblock copolymers with DMAEMA via anionic polymerization is presented; PS‐b‐PDMAEMA, PB‐b‐PDMAEMA, poly(p‐tert‐butoxystyrene)‐b‐PDMAEMA, and PEO‐b‐PDMAEMA. The latter was synthesized using sec‐butyllithium as initiator in presence of the phosphazene base t‐BuP4, enabling a facile changeover from an oxyanion to a carbanion. All reactions resulted in narrowly distributed block copolymers (PDI < 1.1). For PEO‐b‐PDMAEMA, diblock copolymers with a high blocking efficiency and a near‐narrow molecular weight distribution (PDI < 1.40) could be prepared. The advantage of the presented one‐pot synthesis is a significant higher blocking efficiency compared to commercially available PEO macroinitiators under similar conditions.

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Preparation of Monodisperse Polylactide Microspheres by Dispersion Polymerization Using a Polymeric Stabilizer with Hydroxy Groups
Authors: Muranaka Makoto , Ono Tsutomu
Published: December 2008

Monodisperse poly(D,L‐lactide) (PDLLA) microspheres have been prepared by dispersion polymerization of D,L‐lactide with a synthetic polymeric stabilizer. The polymerization is carried out in xylene/heptane (1:2, v/v) at 368 K for 3 h with poly[(dodecyl methacrylate)‐co‐(2‐hydroxyethyl methacrylate)] (P(DMA‐co‐HEMA)). P(DMA‐co‐HEMA) has hydroxy groups as an initiation group for pseudoanionic dispersion polymerization. The particle diameter and the coefficient of variation concerning the diameter distribution of the obtained PDLLA microspheres are 3.9 µm and 4.3%, respectively. In addition, from the results of dynamic light scattering measurements, it is found that P(DMA‐co‐HEMA) and the PDLLA‐grafted copolymer form a micellar structure in solution.

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Structural characterization of flavonoid glycosides by multi‐stage mass spectrometry
Authors: Vukics Viktoria , Guttman András
Published: December 2008

Flavonoids are secondary plant metabolites of great structural variety and high medicinal significance. The search for new chemical entities and the quality control of flavonoid containing natural products require easy‐to‐use but reliable and robust analytical methodologies. For structural elucidation of flavonoids and their glycosides, nuclear magnetic resonance (NMR) and mass spectroscopy (MS) are the generally used techniques. In phytochemical analyses, however, high amounts of flavonoids are difficult to isolate for NMR, thus low sample volume requiring MS based methods are emerging. This review summarizes and compares currently available methods for structural elucidation of flavonoids by LC–MS and LC–MSn, and focuses on the identification options of unknown flavonoid glycosides in complex samples (e.g., plant extracts) with the emphasis on the differentiation of isomeric compounds. © 2008 Wiley Periodicals, Inc., Mass Spec Rev 29:1–16, 2010
Investigation of Barrier Properties of Poly(ethylene vinyl acetate)/Organoclay Nanocomposite Films Prepared by Phase Inversion Method
Authors: Shafiee M. , Ramazani S.A. A.
Published: December 2008

Summary: In this research work, to reduce permeability of poly(ethylene vinyl acetate) packaging films, organoclay nanocomposites of these thermoplastics were prepared by solution method. Organoclay are mixed with polyethylene vinyl acetate (EVA) with 18 and 28% of vinyl acetate (VA) content in solution phase. Solutions of 3, 5 and 7% of organoclay are prepared under reflux condition and then nanocomposite films are prepared by thermal phase inversion method. Morphological and gas barrier properties of different prepared samples have been investigated. Morphology of prepared nanocomposite films and order of exfoliation of clay were investigated using X‐ray diffraction (XRD) and transmission electron microscopy (TEM) instruments. XRD and TEM indicated that the prepared nanocomposites had predominantly intercalated morphologies. Gas permeability measurements showed that the presence of organoclay significantly increases the barrier properties of EVA/nanocomposite films even at the low concentration of clay.
Modeling of Viscoelastic Fluid Flow Behavior in the Circular Die Using the Leonov‐Like Conformational Rheological Constitutive Equations
Authors: Ramazani S.A A. , Kanvisi M.
Published: December 2008

Summary: In this paper, the flow behavior of Leonov‐Like conformational rheological model, which has root in the generalized Poisson bracket formalism based on the conformation tensor, have been studied in the circular die flow. Prediction of the normal stress differences during the flow of these fluids lets us to follow and calculate relaxation dependent phenomena such as die swell. The model predictions have been compared for the four families of mobility expressions. The Study of the model prediction sensitivity to its mobility term shows that model predictions can cover a wide range of rheological behaviors generally observed for polymer melts and solutions in the circular die flow.
Metal Ions Uptake by Chelating Resin Derived from o‐Substituted Benzoic Acid and its Synthesis, Characterization and Properties
Authors: Shah Pathik M. , Shah Ajay V. , Shah Bhavna A.
Published: December 2008

Summary: Chelating resin [AFM] was synthesized by condensation of Anthranilic acid, Formaldehyde with m‐Cresol. The chelating resin was characterized by FTIR Spectra, Elemental Analysis and SEM Photographs. The thermal behavior of the resin was characterized by TGA. The thermodynamic parameters such as Activation Energy (Ea), Order of decomposition (n), Entropy of decomposition (S*), Enthalpy (H*) and Free energy (G*) were calculated by Coats and Redfern method using TGA graph. The chelating behaviour of the prepared resin was studied out with using some metal ions [Ni(II), Cu(II), Zn(II), Cd(II) and Pb(II)]. The sorption capacities of metal ions is found in the following order, Pb(II) < Zn(II) < Cd(II) < Cu(II) < Ni(II). The rate of half exchange was rapid t1/2 < 20 min for lead ion. The separation of binary mixtures [Cu(II) and Zn(II) in brass and Pb(II) and Cd(II)] was successfully carried out using Kd value.
Adsorption Behavior of Metal Ions by Amidoxime Chelating Resins
Authors: Nilchi A. , Rafiee R. , Babalou A. A.
Published: December 2008

In this work, the acrylonitrile (AN) – divinylbenzene (DVB) –methylacrylate (MA) resin was synthesized via suspension polymerization in the presence of toluene as diluent, and benzoylperoxide (BPO) as initiator. The effect of MA, toluene and alkaline treatment on the exchange capacity of the resin were investigated. The results showed that the anion exchange capacity decreased with an increase in the amount of MA, while alkaline treatment had no significant effect. Also, the cation exchange capacity increased with an increase in the amount of hydrophilic agent and reached a maximum point. The sorption equilibrium was achieved relatively fast within 40 mins, and the resin exhibited affinity towards lead (II), copper (II) and in particular uranium (VI). The adsorption of uranium was directly depended up on the pH value. Furthermore, the macroreticular chelating resin, containing amidoxime group had higher adsorption of uranium (VI) in comparison to other metal ions studied. Finally, the alkaline treatment enhanced the potential for much faster adsorption characteristics and the highly porous chelating resin provided a more favorable pore structure for the rapid rate of diffusion of metal ions.
Thermodynamic Analysis of Phase Separation of a Thermoplastic in the Precursors of Different Epoxy‐Amine Systems
Authors: López Joaquín , Rico Maite , Pena Carlos , Montero Belen
Published: December 2008

The miscibility of a thermoplastic, polystyrene (PS), with the precursors of several epoxy‐amine systems has been studied thermodynamically and experimentally. The epoxy‐amine systems were different only in the origin of amino groups, which were provided by a monoamine (MA) and a diamine (DA) in different proportions. Cloud‐point curves (CPC) at conversion zero were reported for five modified systems with different MA‐DA proportion. All CPCs showed an UCST behaviour. CPC shifted to lower temperatures when the ratio of MA/DA in the system increased, meaning that the MA produces an increase in the miscibility of the system. A model based on the Flory‐Huggins theory was used for the thermodynamic analysis, in which the dependence of interaction parameter on temperature and composition, χ(T,ϕ), and the polydispersity of components were considered. A general equation for χ(T,ϕ) also depending on the MA‐DA proportion was reached and used to obtain the phase diagram of the different systems. A high level of agreement between theoretical and experimental CPCs was obtained.
Synthesis and Properties of Highly Swelling PAAm/Chitosan Semi‐IPN Hydrogels
Authors: Mahdavinia Gholam Reza , Pourjavadi Ali , Zohuriaan‐Mehr Mohammad Jalal
Published: December 2008

A semi‐interpenetrating polymer network (semi‐IPN) hydrogel composed of crosslinked chitosan and polyacrylamide (PAAm) was prepared in the presence of formaldehyde as a crosslinker. The swelling capacity of hydrogel was shown to be affected by the crosslinker and the PAAm/chitosan ratio. The PAAm/chitosan semi‐IPN hydrogels are swelled at low pHs that attributed to both osmotic pressure and repulsion of NH groups on chitosan backbones. The swelling of hydrogel in acidic pHs showed that with increasing of chitosan content in the hydrogel, the swelling capacity was increased. But the swelling capacity of hydrogel in neutral pH is reversed, i.e. the higher the PAAm/chitosan ratio, the higher the swelling capacity. The results also indicated that the semi‐IPN hydrogel had different swelling capacity in various pHs. It showed a reversible pH‐responsive behavior at pH 2 and 10.
Phenolic Antioxidant for Polyolefins from Grafted Phenol on Polyethylene Wax
Authors: Khalaf Moayad N. , Shnawa Hussein A. , Goda Mostafa K. , Lazem Mohamed A. , Abd‐Alemam Dia'a A.
Published: December 2008

Summery: This study consists of the preparation of a new polymeric antioxidant from the grafting of phenol on the backbone of chlorinated polyethylene wax by alkylation's reaction in the presence of AlCl3 as catalyst. The chemical structure of the prepared phenolic polyethylene wax(ph ‐ wax) was characterized by FTIR. The thermal oxidation of HDPE was examined by monitoring the amount of O2 uptake by samples of HDPE with the (ph‐wax) volumetrically at 230 °C, also the thermal oxidation degradation of HDPE with the (ph‐wax) derivative was studied by monitoring the weight loss of the samples during heating at 250 °C and under normal air as atmosphere. The results of this study show a decrease in the rate of HDPE oxidation in the presence of ph‐wax at four percent (0.2, 0.4, 0.6 and 0.8) %wt/wt of polymer, while the oxidation time of HDPE increased from (5) min. for pure HDPE to reach (41) min. for (0.8) % sample. The thermograms and thermal data of this study indicate that the stability of HDPE increases with the percent of the (ph‐wax) (0.6 and 0.8) wt/wt%. Generally, these results show that phenolic wax has excellent performance as an antioxidant for polyethylene.
Holistic investment assessment: optimization, risk appraisal and decision making
Authors: Tziralis Georgios , Kirytopoulos Konstantinos , Rentizelas Athanasios , Tatsiopoulos Ilias
Published: December 2008

On deciding for the most appropriate investment when capital restrictions exist, investors define their alternatives and analyze each one of them. Traditionally, the definition, appraisal and analysis stages are treated separately. Herein, an innovative holistic method is proposed for bridging these stages. Within this method, investment attributes definition occurs by genetic algorithm optimization, while the analysis of the investment is realized through simulation. The method also proposes theNPV Expected Shortfalland theNPV Risk Preference Indexas investment evaluation criteria. An illustrative case study of two mutually exclusive renewable energy investment scenarios is also used for demonstration purposes. Copyright © 2008 John Wiley & Sons, Ltd.
A class of implicit variational inequalities and applications to frictional contact
Authors: Capatina Anca , Cocou Marius , Raous Michel
Published: January 2009

This paper deals with the mathematical and numerical analysis of a class of abstract implicit evolution variational inequalities. The results obtained here can be applied to a large variety of quasistatic contact problems in linear elasticity, including unilateral contact or normal compliance conditions with friction. In particular, a quasistatic unilateral contact problem with nonlocal friction is considered. An algorithm is derived and some numerical examples are presented. Copyright © 2009 John Wiley & Sons, Ltd.
Some results concerning the state of bending for transversely isotropic plates
Authors: Passarella Francesca , Zampoli Vittorio
Published: January 2009

In this paper, we present a series of basic theorems for transversely isotropic plates characterized by a state of bending. More precisely, we show a reciprocal theorem and a uniqueness result without positive definiteness assumptions on the elastic coefficients. Moreover, we establish some variational and minimum principles. Finally, we give a Galerkin representation of the solution. Copyright © 2009 John Wiley & Sons, Ltd.
Residual rickets or osteomalacia: a case dating from the 16–18th centuries from Krosno Odrzańskie, Poland
Authors: Haduch E. , Szczepanek A. , Skrzat J. , Środek R. , Brzegowy P.
Published: December 2008

A skeleton from a 16–18th century burial site in Krosno Odrzańskie, Poland, was examined using classical morphological, metric and macroscopic palaeopathological observations, as well as radiography and tomography of the skull and long bones. A wide variety of the observed bone deformations probably occurred as a consequence of past rickets and/or osteomalacia, whose primary cause may also have been chronic renal failure. Preservation of the bones enables a discussion of the cause of such pathological changes. The subject under study appears to be a very interesting example of an individual whose skeleton shows advanced pathological alterations associated with the subject's vitamin D deficiency, overall health conditions and relatively long lifespan. Copyright © 2008 John Wiley & Sons, Ltd.
Taphonomy, life history, and human exploitation of Rhinoceros sinensis at the Middle Pleistocene site of Panxian Dadong, Guizhou, China
Authors: Schepartz L. A. , Miller‐Antonio S.
Published: December 2008

Rhinoceros remains are commonly found in Chinese Pleistocene archaeological localities. This study examines the characteristics of the Rhinoceros sinensis sample from Panxian Dadong, a karst cave in the mountains of western Guizhou province, with a mammalian fauna in association with stone artefacts and human remains from the late Middle Pleistocene (MIS 6‐8). The distribution of skeletal elements shows a predominance of foot (metapodial and phalanges) and lower limb (carpals and tarsals) bones, while the dental age‐at‐death profile, constructed using dental eruption and tooth wear data, is characterised by a high frequency of prime age adult teeth. There is little taphonomic evidence for the involvement of non‐human carnivores or natural agencies in the formation of the faunal assemblage. Instead, it appears that human activities were responsible for the unexpected prevalence of prime age adults. Copyright © 2008 John Wiley & Sons, Ltd.
Synthesis and characterization of thermotropic liquid crystalline polyurethanes from 4,4′‐bis(6‐hydroxyhexoxy) biphenyl and aliphatic diols
Authors: Wei Chun , Gong Yongyang , Yang Xianglian , Wang Min
Published: December 2008

A series of thermotropic liquid crystalline polyurethanes (LCPUs) were synthesized by the polyaddition reactions of 2,4‐toluene diisocyanate (2,4‐TDI) with 4,4′‐bis(6‐hydroxyhexoxy)biphenyl (BHHBP) and aliphatic diol. The intrinsic viscosities of the polymers were measured by Ubbelohde viscometer, and the chemical structure was confirmed by Fourier transform infrared spectroscopy (FT‐IR). The LCPUs were examined by differential scanning calorimetry (DSC), polarized optical microscopy (POM), wide angle X‐ray diffraction (WAXD), and thermogravimetric analysis (TGA). The intrinsic viscosities were 0.56–0.83 dl/g. According to the melting point (Tm) and the isotropic temperature (Ti) of the LCPUs, the temperature range of the liquid crystalline phase became wider with increased number of methylene spacers in the polyurethane. The LCPUs exhibited a nematic phase with a threaded texture and had a wide mesophase temperature range. The decomposition temperature of the LCPUs was  >300°C. On WAXD, the LCPUs give a dispersing peak at 2θ ≈ 20°, and a strong diffraction peak at 2θ ≈ 25°. Copyright © 2008 John Wiley & Sons, Ltd.
Synthesis and properties of poly(acrylamide‐co‐acrylic acid)/polyacrylamide superporous IPN hydrogels
Authors: Ao Haiyong , Huang Miaoliang , Wu Jihuai , Lin Jianming , Tang Qunwei , Sun Hui
Published: December 2008

Poly(acrylamide‐co‐acrylic acid)/polyacrylamide [P(AM‐co‐AA)/PAM] hydrogel with superporous and interpenetrating network (IPN) structure was prepared by a prepolymerization reaction and a synchronous polymerization reaction and frothing process. Scanning electron microscope (SEM) images show that the resultant hydrogel possesses abundant interconnected pores. DSC indicates that the porous structure enhances the swelling ratio and reduces the interaction between water and the hydrogel. In contrast, the IPN by PAM decreases water absorbency and enhances water retentivity. It is found that a superporous stucture in the hydrogel increases the equilibrium swelling ratio and decreases the compressive strength of the hydrogel. On the other hand, the increase in AM oligomer (oligo‐AM) amount decreases the equilibrium swelling ratio and improves the compressive strength of the hydrogel. Therefore, the two‐steps synthesis method can be used to construct a hydrogel with superporous and IPN structure. The swelling and mechanical properties of the hydrogel can be improved effectively. Copyright © 2008 John Wiley & Sons, Ltd.
Biocomposites based on Alfa fibers and starch‐based biopolymer
Authors: Belhassen R. , Boufi S. , Vilaseca F. , López J. P. , Méndez J. A. , Franco E. , Pèlach M. A. , Mutjé P.
Published: December 2008

Biocomposite materials based on Alfa cellulose fibers (esparto grass plant) as reinforcing element and starch‐based biopolymer matrix were prepared and characterized in terms of mechanical performance, thermal properties, and water absorbance behavior. The fibers and the matrix were first mixed in the melted state under mechanical shearing using a plastograph and the obtained composites were molded by injection process. The tensile mechanical analysis showed a linear increase of the composite flexural and tensile modulus upon increasing the fiber content, together with a sharp decrease of the elongation at break. The fibers′ incorporation into the biopolymer matrix brings about an enhancement in the mechanical strength and the impact strength of the composite. Dynamic mechanical thermal analysis (DMTA) investigation showed two relaxations occurring at about −30 and 35°C. The addition of Alfa fibers enhanced the storage modulus E′ before and after Tα, which is consistent with the reinforcing effect of Alfa cellulose fibers. Copyright © 2008 John Wiley & Sons, Ltd.
Estrogens and the risk of complex regional pain syndrome (CRPS)
Authors: de Mos M. , Huygen F. J. P. M. , Stricker B. H. Ch. , Dieleman J. P. , Sturkenboom M.C. J. M.
Published: December 2008

Objective

Since complex regional pain syndrome (CRPS) shows a clear female predominance, we investigated the association between the cumulative as well as current exposure to estrogens, and CRPS.

Methods

A population‐based case–control study was conducted in the Integrated Primary Care Information (IPCI) project in the Netherlands. Cases were identified from electronic records (1996–2005) and included if they were confirmed during a visit (using International Association for the Study of Pain Criteria), or had been diagnosed by a specialist. Controls were matched to cases on gender, age, calendar time, and injury. Measures of cumulative endogenous estrogen exposure were obtained by questionnaire and included age of menarche and menopause, menstrual life, and cumulative months of pregnancy and breast‐feeding. Current estrogen exposure at CRPS onset was retrieved from the electronic medical records and determined by current pregnancy or by the use of oral contraceptive (OC) drugs or hormonal replacement therapy (HRT).

Results

Hundred and forty‐three female cases (1493 controls) were included in analyses on drug use and pregnancies, while cumulative endogenous estrogen exposure was studied in 53 cases (58 controls) for whom questionnaire data were available. There was no association between CRPS and either cumulative endogenous estrogen exposure, OC, or HRT use. CRPS onset was increased during the first 6 months after pregnancy (OR: 5.6, 95%CI: 1.0–32.4), although based on small numbers.

Discussion

We did not find an association between CRPS onset and cumulative endogenous estrogen exposure or current OC or HRT use, but more powered studies are needed to exclude potential minor associations. Copyright © 2008 John Wiley & Sons, Ltd.
The Australian rise of esomeprazole—was expenditure on samples a contributor?
Authors: Kyle Gregory J. , Nissen Lisa M. , Tett Susan E.
Published: December 2008

Background

Administrative data from the Australian Pharmaceutical Benefits Scheme (PBS) showed rapid growth of esomeprazole dispensing when it was launched. Australia has universal prescription medicine coverage (the PBS), which included esomeprazole from August 2002. Free samples of new medicines are commonly provided to doctors.

Objectives

To determine if a relationship exists between marketing expenditure on samples and the dispensing rate for esomeprazole in Australia between June 2002 and September 2006.

Methods

Quarterly sample expenditures at product/brand level for proton pump inhibitors (PPIs) for Australian general practitioners were obtained for July 2002 to September 2006. Corresponding PBS dispensing data were obtained for all PPIs and converted to defined daily dose (DDD)/1000 population/day. Spending on samples was calculated as dollars per dispensed prescription and plotted against time on the Australian market.

Results

Total PPI usage increased from 34.2 to 50.8 DDD/1000 population/day over the study period. Expenditure on samples per dispensed prescription was higher when a PPI was new on the market and diminished over 5–6 years to a relatively constant level. The rapid decline in this ratio was demonstrated by a case study following esomeprazole from launch in Australia for almost 5 years clearly demonstrating the initial investment to drive sales.

Conclusion

A relationship appears to exist between expenditure on esomeprazole samples and its usage in Australia. A high initial investment was followed by a rapid reduction in cost per prescription dispensed, predominantly due to growth in market share. This trend was consistent with other PPIs. Copyright © 2008 John Wiley & Sons, Ltd.
Medication adherence, first episode duration, overall duration and time without therapy: the example of bisphosphonates
Authors: Roughead Elizabeth E. , Ramsay Emmae , Priess Kym , Barratt John , Ryan Philip , Gilbert Andrew L.
Published: December 2008

Purpose

We aimed to determine the duration of first episode of therapy and overall therapy as well as time without treatment for bisphosphonates.

Methods

Data were extracted from Department of Veterans' Affairs (DVA) dataset for those with at least one dispensing for a bisphosphonate between April 2001 and April 2007. Episodes of use were determined as the number of treatment days between the first and last prescription plus 35 days once a dispensing gap of 105 days had been reached, or where no treatment gaps were recorded, the study end date. Kaplan–Meier analyses were undertaken for the first episode of use, overall duration and time without treatment.

Results

When considering only the duration of first episode, median bisphosphonate use was 1.19 years. The median duration extended to 3.27 years when all episodes of use were considered. Overall, 52.0% of subjects reached at least 3 years of treatment and 66.5% of existing users had a duration of at least 3 years. Median time without treatment was 1.65 years. Overall, 81% of the cohort had enough medicine dispensed to be considered adherent throughout their duration of use.

Conclusion

Over 50% of subjects and 66% of existing users had duration consistent with the minimum recommended. Adherence within an episode was high. The focus for improving duration of bisphosphonate use should be on reducing the time without treatment, rather than adherence at the time of use. Studies assessing only the first episode of use in new users of medicines may underestimate duration. Copyright © 2008 John Wiley & Sons, Ltd.
Frequency of ill‐founded off‐label prescribing in Dutch general practice
Authors: Gijsen Ronald , Jochemsen Hadassa , van Dijk Liset , Caspers Peter
Published: December 2008

Purpose

The aim of this study is to quantify the extent of ill‐founded off‐label drug prescriptions in Dutch general practice. The study is based upon information on both the prescription itself and the patient's medical history.

Methods

In total, 48 combinations of drugs and off‐label indications were selected from a list of 477 known off‐label combinations. These 48 combinations were considered as ill‐founded since pharmacotherapeutic handbooks or clinical practice guidelines did not provide evidence for their efficacy and safety. They were considered to be relevant for investigation in general practice. We used a nationally representative information network of 85 general practices in the Netherlands. By using information on the patients' diagnoses and medication in the period before and after the prescription, we were able to exclude non‐conclusively off‐label prescriptions.

Results

Twenty‐one of the selected 48 off‐label combinations did not occur in Dutch general practice. The drugs with the highest proportion of ill‐founded off‐label prescriptions were betahistine (26.7%), celecoxib (16.3%) and etoricoxib (12.5%). In total, 18.2% of the prescriptions, which were initially assessed as ill‐founded off‐label, were re‐evaluated as on‐label, after considering the patient's medical history.

Conclusions

Ill‐founded off‐label prescribing in Dutch general practice is limited for 48 relevant combinations of drugs and off‐label indications. In order to overcome limitations in registration databases, it is useful to look at as much information as possible—for example, co‐medication and co‐morbidity—when determining off‐label prescribing. Studying ill‐founded off‐label prescribing should be performed on a day‐to‐day basis, especially for recently introduced drugs. Copyright © 2008 John Wiley & Sons, Ltd.
Hemorrhagic stroke associated with antidepressant use in patients with depression: does degree of serotonin reuptake inhibition matter?
Authors: Chen Yan , Guo Jeff J. , Patel Nick C.
Published: December 2008

Objective

This study aimed to determine whether the degree of serotonin (5‐HT) reuptake inhibition affects risk of hemorrhagic stroke associated with antidepressant use in patients with depression.

Method

A population‐based, nested case‐control study was performed using a managed care medical claims database. Ninety two depressed patients with a diagnosis of hemorrhagic stroke were identified and matched with 552 controls by age, sex, and year of index date of depression (IDD). Diagnoses of depression, hemorrhagic stroke, and other medical comorbidities were identified using ICD‐9 codes. Antidepressants were classified as high, medium, or low reuptake inhibition based on their affinities for the 5‐HT reuptake transporter, determined using their respective equilibrium dissociation constants (KD; high: KD < 1 nM; medium: 1 ≤ KD < 10 nM; low: KD ≥ 10 nM). Conditional logistic regression analysis was performed to estimate the crude and adjusted odds ratios (ORs) with 95% confidence intervals (CIs) of the risk of hemorrhagic stroke.

Results

Compared to non‐users of antidepressants, risk of hemorrhagic stroke did not significantly differ between patients who had ever used antidepressants with high (OR = 0.82; 95% CI = 0.44–1.55), medium (OR = 0.93; 95% CI = 0.37–2.31), or low (OR = 0.38; 95% CI = 0.11–1.41) 5‐HTT inhibition.

Conclusion

Risk of hemorrhagic stroke associated with antidepressant use may not be related to an antidepressant's degree of 5‐HT reuptake inhibition. Given the limitations of this study, additional studies are needed to confirm these findings. Copyright © 2009 John Wiley & Sons, Ltd.
Miscibility, morphology and thermal properties of poly(para‐dioxanone)/poly(D,L‐lactide) blends
Authors: Bai Wei , Zhang Zhi‐ping , Li Qing , Chen Dong‐Liang , Chen He‐Chun , Zhao Na , Xiong Cheng‐Dong
Published: December 2008

BACKGROUND: Poly(para‐dioxanone) (PPDO) is a biodegradable polyester with excellent biodegradability, bioabsorbability, biocompatibility and mechanical flexibility. However, its high cost and relatively fast degradation rate have hindered the development of commercial applications. Blending with other polymers is a simple and convenient way of modifying the properties of aliphatic polyesters. Poly(D,L‐lactide) (PDLLA) is another polyester that has been extensively studied for biomedical applications due to its biocompatibility and suitable degradation rate. However, to our knowledge, blends of PPDO/PDLLA have not been reported in the literature.

RESULTS: A series of biodegradable polymers were blended by solution co‐precipitation of PPDO and PDLLA in various blend ratios. The miscibility, morphology and thermal properties of the materials were investigated. DSC curves for all blends revealed two discrete glass transition temperatures which matched the values for pure PPDO and PDLLA. SEM images of fracture surfaces displayed evidence of phase separation consistent with the DSC results. The contact angles increased with the addition of PDLLA.

CONCLUSION: PPDO/PDLLA blends exhibit two distinct glass transition temperatures that remain nearly constant and correspond to the glass transition temperatures of the homopolymers for all blend compositions, indicating that blends of PPDO and PDLLA are immiscible. Images of the surface obtained using SEM were also suggestive of a two‐phase material. The crystallinity of the PPDO phase in the blends was affected by the PDLLA content. The mechanical properties of the blends changed dramatically with composition. Adding PDLLA makes the blends less hydrophilic than PPDO. Copyright © 2008 Society of Chemical Industry
Morphology of nylon 1212 toughened with a maleated EPDM rubber
Authors: Wang Yudong , Wang Wanjie , Peng Fu , Liu Minying , Zhao Qingxiang , Fu Peng‐Fei
Published: December 2008

BACKGROUND: Polyamides, or nylons, are an attractive class of engineering polymers due to their excellent strength and stiffness, low friction and chemical and wear resistance. However, they are highly notch‐sensitive, i.e. they are often ductile in the un‐notched state, but fail in a brittle manner when notched. A super‐tough nylon 1212 was prepared by blending nylon 1212 with ethylene propylene diene monomer (EPDM) grafted with maleic anhydride (MA). The morphologies of Izod impact fracture surfaces as well as xylene‐etched surfaces of the nylon were thoroughly investigated using scanning electron microscopy (SEM).

RESULTS: The fracture morphology and the impact strength of the nylon 1212 blends are very well correlated. The impact fracture surface of the blends exhibits certain characteristic features, such as the observation of fiber‐like sticks when etched with boiling xylene, formed during the impact fracture process. SEM images of xylene‐etched surfaces as well as the results of X‐ray energy dispersive spectroscopy suggest that the successful toughening of nylon 1212 with EPDM‐graft‐MA is due to the reaction between the anhydride of EPDM‐graft‐MA and the amine end‐groups of nylon 1212, leading to the formation of a homogenous graft copolymer system.

CONCLUSION: The copolymer system, acting as a surfactant, reduces the interfacial tension between nylon 1212 and EPDM‐graft‐MA and produces a highly compatible super‐tough nylon 1212. Copyright © 2008 Society of Chemical Industry