bluuebunny/crossref_metadata_2025_split huggingface dataset:
Land use and economic change in the post‐frontier upland Philippines
Authors: Eder J. F. 
Published: March 2006

AbstractChanges in land use and in the nature of farm enterprises in the upland Philippines are examined through the lens of household economic strategies, using data obtained on Palawan Island and with particular attention to non‐agricultural employment diversification. Short fallow intervals and small farm sizes are today common throughout upland Palawan. In addition, as upland farming has become more of an occupation of specific household members and less the way of life of entire households, many upland farms are specialized in particular crops. Such specializations, however, change over time as households undergo growth and domestic cycling and some members establish new income sources and residential bases in the lowlands. Meanwhile, restrictions on new forest clearance and other developments that make it difficult for upland households to secure an adequate living from farming alone have greatly increased collection pressures on non‐timber forest products. These and other changes are reconfiguring the role of women in household economy and generating new axes of regional economic integration. Despite considerable land and other resource degradation in the uplands, some causes for optimism are found in the spontaneous adoption of agroforestry practices and in the emergence of new identities configured in part around notions of environmental well‐being. Copyright © 2006 John Wiley & Sons, Ltd.
Syntheses, Structures and Proton Conductivities of Polyphthalazinone Ionomers Derived from a Direct NC Coupling Reaction
Authors: Chen Yulin , Meng Yuezhong , Wang Shuanjin , Tian Shuanghong , Hay Allan S. 
Published: March 2006

AbstractSummary: Nafion perfluorinated resins that contain perfluorosulfonic acid groups have outstanding properties as membranes in polymer electrolyte membrane (PEM) fuel cells when used only at temperatures lower than 80 °C. At higher temperatures, dehydration of the membrane occurs with a concomitant loss of conductivity. In this paper, we report a new approach to synthesize polyphthalazinone ionomers via an NC coupling reaction. The sulfonated polymers produced showed excellent thermal and oxidative stability because of their specially designed structure. Membranes cast from solution possessed good water affinity and high proton conductivity. Different bisphthalazinone monomers resulted in varying properties of the corresponding polymers. The membranes exhibited excellent resistance both to hydrolysis and oxidation, demonstrating their promising application as proton exchange membranes in PEM fuel cells. The relationship between the structure and properties for the synthesized polymeric ionomers was discussed.Polyphthalazinone ionomers.magnified imagePolyphthalazinone ionomers.
A Column By‐Pass System and Its Application in High‐Temperature Size‐Exclusion Chromatography
Authors: Aust Nicolai , O'Donohue Stephen , Yakhoul Amjad Jade , Zash Najib 
Published: March 2006

AbstractSummary: A new by‐pass system for chromatographic columns is presented and its efficiency in detecting disturbances during the chromatographic run is demonstrated. The system, designed for HT SEC, is based on a ten‐port valve and allows by‐passing without the need of time and work consuming replacement of the column by a capillary and vice versa. In addition, the construction guarantees a continuous low flow of eluent through the column also when by‐passed, which helps substantially to prolong lifetime of the SEC column at high temperature. Combining the chromatograph with “absolute” detectors, e.g. a light‐scattering detector or viscometer, erroneous molecular parameters caused by polymer degradation due to wrong column selection or run conditions can be easily detected by comparing measurements with and without the column. Therefore, using the chromatograph in by‐pass mode, it can be regarded as an additional, independent apparatus, delivering e.g. the $\overline M _{\rm w}$ or [η] of a polymer sample. The by‐pass system enables a reliable calibration of concentration detectors in chromatography. With the aid of a detector calibration curve, even a small amount of polymer adsorbed in the SEC column can be detected by comparing the peak area derived from the concentration detector to the one to be expected from the calibration data. The column by‐pass could find application except for HT SEC also in other fields of HPLC.Scheme of the by‐pass system.magnified imageScheme of the by‐pass system.
Loss of p75 neurotrophin receptor expression accompanies malignant progression to human and murine retinoblastoma
Authors: Dimaras H. , Coburn B. , Pajovic S. , Gallie B.L. 
Published: March 2006

AbstractWe studied the expression of pro‐apoptotic neurotrophin receptor p75 (p75NTR) in human and murine retinoblastoma, compared to normal retina, and examined changes in p75NTR expression with the onset of apoptosis in the course of murine retinoblastoma progression, using immunohistochemistry and quantitative real‐time RT‐PCR. The murine retinoblastoma is induced by retinal specific expression of SV40 T‐antigen (TAg), which blocks the function of the retinoblastoma protein (pRB) and related proteins, and is a well‐studied model that closely simulates human retinoblastoma. The majority of human retinoblastoma either lacked or expressed decreased levels of p75NTR mRNA, compared to human retina. Moreover, p75NTR protein was not detected in any tumor studied, unlike normal retina. Like human retinoblastoma, advanced murine retinoblastoma did not express p75NTR. However, before tumors emerged, small clusters of TAg‐positive cells coexpressed p75NTR and activated caspase‐3, a marker of apoptosis. Furthermore, in three rare human eyes containing retinoblastoma adjacent to regions resembling the benign retinal tumor retinoma, both normal retina and retinoma‐like tissue expressed p75NTR protein, while the retinoblastoma did not. We suggest that p75NTR loss accompanies progression from retinoma to retinoblastoma. © 2006 Wiley‐Liss, Inc.
Data‐driven variation source identification for manufacturing process using the eigenspace comparison method
Authors: Jin Nong , Zhou Shiyu 
Published: March 2006

AbstractVariation reduction of manufacturing processes is an essential objective of process quality improvement. It is highly desirable to develop a methodology of variation source identification that helps quickly identify the variation sources, hence leading to quality improvement and cost reduction in manufacturing systems. This paper presents a variation source identification method based on the analysis of the covariance matrix of process quality measurements. The identification procedure utilizes the fact that the eigenspace of the quality measurement covariance matrix can be decomposed into a subspace due to variation sources and a subspace purely due to system noise. The former subspaces for different samples will be the same if the same variation sources dominate. A testing procedure is presented, which can determine the closeness of the subspaces under sampling uncertainty. A case study is conducted to illustrate the effectiveness of this methodology. © 2006 Wiley Periodicals, Inc. Naval Research Logistics, 2006.
Age‐dependent and task‐related volume changes in the mushroom bodies of visually guided desert ants, Cataglyphis bicolor
Authors: Kühn‐Bühlmann Simone , Wehner Rüdiger 
Published: March 2006

AbstractDesert ants of the genus Cataglyphis are skillful long‐distance navigators employing a variety of visual navigational tools such as skylight compasses and landmark guidance mechanisms. However, the time during which this navigational toolkit comes into play is extremely short, as the average lifetime of a Cataglyphis forager lasts for only about 6 days. Here we show, by using immunohistochemistry, confocal microscopy, and three‐dimensional reconstruction software, that even during this short period of adult life, Cataglyphis exhibits a remarkable increase in the size of its mushroom bodies, especially of the visual input region, the collar, if compared to age‐matched dark‐reared animals. This task‐related increase rides on a much smaller age‐dependent increase of the size of the mushroom bodies. Due to the variation in body size exhibited by Cataglyphis workers we use allometric analyses throughout and show that small animals exhibit considerably larger task‐related increases in the sizes of their mushroom bodies than larger animals do. It is as if there were an upper limit of mushroom body size required for accomplishing the ant's navigational tasks. © 2006 Wiley Periodicals, Inc. J Neurobiol, 2006
Lesion‐induced neurogenesis in the hypothalamus is involved in behavioral recovery in adult ring doves
Authors: Chen Gang , Bonder Edward M. , Cheng Mei‐Fang 
Published: March 2006

AbstractAlthough neurogenesis in the brain of adult vertebrates is region dependent, lesion induces generation of new neurons in non‐neurogenic brain regions. These findings raise the question of the role of new neurons in brain repair and functional recovery. We addressed this question by applying previous observations that electrolytic lesion induced neurogenesis in the ventromedial nucleus (VMN) of the hypothalamus in adult ring doves. Such lesions disrupted the male's courtship behavior, which could be reinstated after rehabilitation with a female. We investigated whether lesion‐induced newborn neurons in the VMN facilitate the recovery of courtship behavior in the lesioned birds. We conducted systematic observations of cytological, morphological, and neuroanatomical changes in the lesioned VMN, and concurrently we monitored behavioral changes. Using a multitude of specific cell markers, we found a well‐circumscribed cellular zone that proliferated actively. This highly proliferative zone initially appeared along the periphery of the lesion site, where cells had high levels of expression of neuronal, glial, and neurovascular markers. As newborn neurons matured at the lesion site, the necrosis gradually decreased, whereas a downsized proliferative zone relocated to a region ventral to the VMN. Some of the mature neurons were found to project to the midbrain vocal nuclei. Restoration of these projection neurons coincided with the recovery of courtship vocalization. Finally, we found that a social factor, that is, when the male doves were cohoused with a mate, facilitated neurogenesis and behavioral recovery. These results suggest that lesion‐induced neurogenesis contributes to behavioral recovery in adult animals. © 2006 Wiley Periodicals, Inc. J Neurobiol, 2006
Activity‐dependent release of tissue plasminogen activator from the dendritic spines of hippocampal neurons revealed by live‐cell imaging
Authors: Lochner Janis E. , Honigman Leah S. , Grant Wilmon F. , Gessford Sarah K. , Hansen Alexis B. , Silverman Michael A. , Scalettar Bethe A. 
Published: March 2006

AbstractTissue plasminogen activator (tPA) has been implicated in a variety of important cellular functions, including learning‐related synaptic plasticity and potentiating N‐methyl‐D‐aspartate (NMDA) receptor‐dependent signaling. These findings suggest that tPA may localize to, and undergo activity‐dependent secretion from, synapses; however, conclusive data supporting these hypotheses have remained elusive. To elucidate these issues, we studied the distribution, dynamics, and depolarization‐induced secretion of tPA in hippocampal neurons, using fluorescent chimeras of tPA. We found that tPA resides in dense‐core granules (DCGs) that traffic to postsynaptic dendritic spines and that can remain in spines for extended periods. We also found that depolarization induced by high potassium levels elicits a slow, partial exocytotic release of tPA from DCGs in spines that is dependent on extracellular Ca+2 concentrations. This slow, partial release demonstrates that exocytosis occurs via a mechanism, such as fuse‐pinch‐linger, that allows partial release and reuse of DCG cargo and suggests a mechanism that hippocampal neurons may rely upon to avoid depleting tPA at active synapses. Our results also demonstrate release of tPA at a site that facilitates interaction with NMDA‐type glutamate receptors, and they provide direct confirmation of fundamental hypotheses about tPA localization and release that bear on its neuromodulatory functions, for example, in learning and memory. © 2006 Wiley Periodicals, Inc. J Neurobiol, 2006
Facing up to the challenges of the practice development unit: a leader's perspective
Authors: Sheehan Nicola , Hayles Jean 
Published: March 2006

AbstractThe Orthopaedic Unit at the Calderdale Royal Hospital began its journey to become a Practice Development Unit (PDU) in October 2003. The Unit has currently achieved Stage 1 accreditation and are presently striving to achieve full accreditation.One of the important factors required in a successful PDU is having effective leadership that is able to both motivate the team and achieve the desired results.This article is a reflective piece examining the problems and obstacles that were encountered by the two leaders of the PDU on their journey to be a fully accredited unit. These problems included lack of team ownership, lack of devolved leadership and lack of time. The article also sets out ways in which these problems have been overcome, and gives the reader practical tips on things to take into account before becoming a leader of a PDU. Copyright © 2006 John Wiley & Sons Ltd
Bridging the gap: learning with patient teachers in health professional education
Authors: O'Neill Fiona , Morris Penny , Symons Jools 
Published: March 2006

AbstractThis paper explores the value and contribution of patient voices in health professional education. The important changes in policy and practice that are slowly transforming the way that services are provided and experienced by people who have a long‐term condition challenges traditional approaches to health professional education. The authors describe their philosophy and approach that supports health professionals to learn from patient voices. The value of the approach extends beyond the insights and support for learners but also has an impact on the individuals who contribute their expertise and knowledge as part of the Patients as Teachers team. Valuing and supporting members of the local community to get involved in professional education is one way of opening up the ‘ivory tower’ and challenges assumptions about who are the teachers and who are the learners. Copyright © 2006 John Wiley & Sons, Ltd.
Innovation in Substance Misuse Services: the contribution of the health care assistant
Authors: Ord Stephen , Sims John 
Published: March 2006

AbstractThis article describes the unique developing role of the health care assistant within a statutory substance misuse service in North West Wales. The main focus of the paper is how the evolving role of the health care assistant has contributed to the enhancement of services delivered to intravenous (illicit) drug users. The first author is the only health care assistant employed by the Substance Misuse Service and was a voluntary worker prior to appointment within the trust. A description is given of how the ‘mould’ was broken. An explanation of how this came about reflects the innovative changes that have been facilitated by a management style resulting in a better quality of service provision. The role is still developing within the service but to date has been instrumental in the generation of sustainable innovation within the service. Copyright © 2006 John Wiley & Sons, Ltd.
Differential post‐translational modifications of transthyretin in Alzheimer's disease: A study of the cerebral spinal fluid
Authors: Biroccio Antonino , del Boccio Piero , Panella Marta , Bernardini Sergio , Di Ilio Carmine , Gambi Domenico , Stanzione Paolo , Sacchetta Paolo , Bernardi Giorgio , Martorana Alessandro , Federici Giorgio , Stefani Alessandro , Urbani Andrea 
Published: March 2006

AbstractTransthyretin (TTR) is a 55 kDa homotetrameric protein. TTR in the cerebral spinal fluid (CSF) is primarily synthesized by the choroid plexus. TTR can bind to the β‐amyloid peptide and a number of familial amyloidosis diseases (familial amyloid polyneuropathy) have been associated with its allele variants. In a transgenic mice model overexpression of TTR was positively correlated with a neuroprotective effect from the pathogenic APPsw mutation. TTR has a free reactive sulphydryl moiety located on the Cys10 residue which has been implicated to undergo a variety of oxidation reactions. To examine the neuroprotective role of TTR, we investigated the conjugated forms of TTR with cysteine (Cys) and cysteinglycine (CsyGly) in the CSF of 39 probable Alzheimer's disease (AD)‐affected subjects and in a cohort of subjects without cognitive impairment (27 subjects). Linear MALDI‐TOF MS experiments were employed to obtain high‐resolution protein profiling of TTR isoforms. Nano‐LC‐TANDEM MS combined with reflectron MALDI‐TOF‐MS was used to unequivocally assign the investigated TTR‐conjugate signals. Our results indicate a differential distribution of TTR‐Cys and TTR‐CsyGly adducts. Both oxidized forms of TTR are significantly less abundant in the AD group (p = 0.0001). The investigated population (66 subjects) was then diagnosed using the ratio of conjugated TTR to free TTR in each subject. A sensitivity >90% and a specificity >70% were derived from a receiver operating characteristic curve when the overall cohort is analysed by the TTR‐Cys signals. This manuscript is the first report describing the presence of differential post‐translational oxidations of TTR in the CSF of AD patients.
Synthesis of poly(glycolic acid) in ionic liquids
Authors: Dali Souad , Lefebvre Hervé , Gharbi Rachid El , Fradet Alain 
Published: March 2006

AbstractThe synthesis of poly(glycolic acid) (PGA) by polyesterification of glycolic acid was studied using ionic liquids, mainly 1,3‐dialkylimidazolium salts, as reaction media. The 1H NMR spectra of PGA oligomers were assigned and end‐group signals were used to follow the reaction. Low PGA yields were obtained by the direct polyesterification of glycolic acid at 200–240 °C, because of monomer evaporation during the reaction. On the other hand, PGAs of DPn up to 45 were obtained by the postpolycondensation of a preformed oligomer in 1‐butyl‐3‐methylimidazolium bis(trifluoromethylsulfonyl)amide (BMIm+Tf2N−). The precipitation of PGA in reaction medium at long reaction times limited the achievable molar mass. Rate constants were determined for catalyzed and noncatalyzed reactions, assuming a second‐order reaction mechanism. The efficiency of esterification catalysts such as Zn(OAc)2 was low in these media, as only about twofold increases in reaction rate were observed. This was assigned to the preferential interaction of Zn2+ with ionic liquid anion instead of the polymer carboxylic acid end‐groups. © 2006 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 44: 3025–3035, 2006
Controlled grafting from poly(vinylidene fluoride) films by surface‐initiated reversible addition–fragmentation chain transfer polymerization
Authors: Chen Yiwang , Sun Wei , Deng Qilan , Chen Lie 
Published: March 2006

AbstractA reversible addition–fragmentation chain transfer (RAFT) polymerization technique was applied to graft polymerize brushes of poly(methyl methacrylate) (PMMA) and poly(poly(ethylene glycol) monomethacrylate) (PPEGMA) from poly(vinylidene fluoride) (PVDF) surfaces. PVDF surfaces were exposed to aqueous LiOH, followed by successive reductions with NaBH4 and DIBAL‐H to obtain hydroxyl functionality. Azo‐functionalities, as surface initiators for grafting, were immobilized on the PVDF surfaces by esterification of 4,4′‐azobis(4‐cyanopentanoic acid) and the surface hydroxyl groups. The chemical composition and surface topography of the graft‐functionalized PVDF surfaces were characterized by X‐ray photoelectron spectroscopy, attenuated total reflectance‐FTIR spectroscopy, and atomic force microscopy. Kinetics studies revealed a linear increase in the graft concentration of PMMA and PPEGMA with the reaction time, indicating that the chain growth from the surface was consistent with a “controlled” or “living” process. The living chain ends were used as the macroinitiator for the synthesis of diblock copolymer brushes. Water contact angles on PVDF films were reduced by surface grafting of PEGMA and MMA. © 2006 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 44: 3071–3082, 2006
Ultrahigh molecular weight polyethylene produced by a bis(phenoxy‐imine) titanium complex supported on latex particles
Authors: Naundorf C. , Matsui S. , Saito J. , Fujita T. , Klapper M. , Müllen K. 
Published: March 2006

AbstractThe applicability of latex particle supports for non‐Cp type metallocene catalysts for ethylene polymerization is presented. Polystyrene latex particles were prepared by miniemulsion polymerization and functionalized with poly(ethyleneoxide)chains and pyridyl groups on the surface. These latex particles were chosen to demonstrate that a support with nucleophilic substituents on the surface can act as a carrier for a (phenoxy‐imine) titanium complex (titanium FI‐catalyst) to produce ultrahigh molecular weight polyethylene (UHMWPE). The composition of the support, the concentration of pyridyl groups on the surface, and the crosslinking of the support were optimized to provide a system where the FI‐catalyst resulted in the formation of polyethylene with a Mw of more than 6,000,000 and a relatively narrow molecular weight distribution of 3.0 ± 0.5. High activities for long polymerization times greater than 6 h resulted in a catalyst system exhibiting productivities of up to 15,000 g PE/g cat. or 7,000,000 g PE/g Ti. The resulting polymer properties showed that nucleophilic groups on the latex particle support did not negatively impact the catalyst by blocking the active site but instead created a stable environment for the titanium catalyst. In particular, pyridyl groups on the surface of the latex particle stabilized the catalyst system probably by trapping trimethylaluminium. © 2006 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 44: 3103–3113, 2006
Cationic photopolymerization of alkyl glycidyl ethers
Authors: Crivello James V. 
Published: March 2006

AbstractAn investigation of the photoactivated cationic ring‐opening frontal polymerizations of a series of alkyl glycidyl ethers was carried out with the aid of a novel technique, optical pyrometry. With this technique, the effects of various experimental parameters, such as the photoinitiator type and concentration, as well as the effects of the monomer structure on the frontal behavior of these monomers were examined. Upon irradiation with UV light, the photopolymerizations of many alkyl glycidyl ethers displayed a prominent induction period at room temperature as the result of the formation of long‐lived, relatively stable secondary oxonium ions. The input of only a small amount of thermal activation energy was required to induce the further reaction of these species with the consequent autoaccelerated exothermic ring‐opening polymerization. Photoactivated frontal polymerizations were observed for both mono‐ and polyfunctional alkyl glycidyl ether monomers. The ability of monomers to exhibit frontal behavior was found to be related to their ability to stabilize the secondary oxonium ion intermediates through hydrogen‐bonding effects. © 2006 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 44: 3036–3052, 2006