bluuebunny/crossref_metadata_2025 huggingface dataset:
Water quality in the River Clyde: a case study of additive and interaction models
Authors: McMullan A. , Bowman A. W. , Scott E. M.
Published: January 2007

Additive models are widely used to provide very flexible and effective descriptions of regression data where assumptions of linear relationships are too restrictive. However, these models usually assume independent errors and there are many applications where the data are correlated. This is often true in environmental settings and an application to water quality modelling in the River Clyde is described. Methods of fitting and analysing an additive model in this setting are discussed. An approach which fits an additive model in the usual way but incorporates the correlated error structure into the assessment of components is described. The methods are applied to the Clyde data to identify the factors which affect water quality, as well as spatial and temporal trends. Interaction terms, which allow the effects of explanatory variables to change smoothly with position down the river, are also explored. Particular emphasis is placed on approximateFtests to identify the most suitable models and the presence and nature of particular covariate effects. Copyright © 2007 John Wiley & Sons, Ltd.
Bayesian prediction of rainfall records using the generalized exponential distribution
Authors: Madi Mohamed T. , Raqab Mohammad Z.
Published: January 2007

The Los Angeles rainfall data are found to fit well to the two‐parameter generalized exponential (GE) distribution. A Bayesian parametric approach is described and used to predict the behavior of further rainfall records. Importance sampling is used to estimate the model parameters, and the Gibbs and Metropolis samplers are used to implement the prediction procedure. Copyright © 2007 John Wiley & Sons, Ltd.
A comparison of approaches to estimating confidence intervals for willingness to pay measures
Authors: Hole Arne Risa
Published: January 2007

This paper describes four approaches to estimating confidence intervals for willingness to pay measures: the delta, Fieller, Krinsky Robb and bootstrap methods. The accuracy of the various methods is compared using a number of simulated datasets. In the majority of the scenarios considered all four methods are found to be reasonably accurate as well as yielding similar results. The delta method is the most accurate when the data is well‐conditioned, while the bootstrap is more robust to noisy data and misspecification of the model. These conclusions are illustrated by empirical data from a study of willingness to pay for a reduction in waiting time for a general practitioner appointment in which all the methods produce fairly similar confidence intervals. Copyright © 2007 John Wiley & Sons, Ltd.
Informed consent in advanced laryngeal cancer
Authors: Foote Robert L. , Brown Paul D. , Garces Yolanda I. , Okuno Scott H. , Miller Robert C. , Strome Scott E.
Published: January 2007

Purpose.

This study was designed to evaluate the relationship between the informed consent process and the treatment received by patients with advanced laryngeal cancer.

Methods.

The study group was composed of 101 consecutive patients who were eligible for the Department of Veterans Affairs Laryngeal Cancer Study Group and Radiation Therapy Oncology Group/Head and Neck Intergroup (RTOG 91‐11) larynx preservation clinical trials and who underwent treatment at the Mayo Clinic during the years 1985 to 2000. Records were reviewed to evaluate the effect that referral to an oncologist, discussion and documentation of treatment alternatives by the surgeon, offering a chance at a larynx conservation surgical procedure, and treatment recommendation made by the surgeon have on the treatment chosen and received by the patient.

Results.

Discussion of treatment alternatives by the surgeon (p = .0054), referral to an oncologist (p < .0001), offering a chance for a larynx conservation surgical procedure (p = .047), and treatment recommended by the surgeon (p < .0001) were significantly related to the treatment received by the patient.

Conclusion.

The treatment received by a patient with advanced laryngeal cancer is determined by the treatment recommended by the surgeon, referral to an oncologist, discussion of treatment alternatives by the surgeon, and offering a chance for a larynx conservation surgical procedure. © 2007 Wiley Periodicals, Inc. Head Neck 29:, 2007.
Infrahyoid fascio‐myocutaneous flap as an alternative to free radial forearm flap in head and neck reconstruction
Authors: Deganello Alberto , Manciocco Valentina , Dolivet Gilles , Leemans C. René , Spriano Giuseppe
Published: January 2007

Background.

The use of microvascular free flaps is currently the favored method for the reconstruction of defects after resection of head and neck cancer. The flap most commonly used for head and neck reconstruction is the free radial forearm flap, but the less popular infrahyoid flap represents a good alternative in selected cases. This flap has proven to be helpful in the reconstruction of a wide range of moderate‐sized head and neck defects.

Methods.

We reviewed a series of 13 patients with defects resulting from cancer of the head and neck, who underwent infrahyoid flap reconstruction as an alternative to free radial forearm flap. The series includes 12 squamous cell carcinomas arising from the oral cavity and oropharynx, and 1 Merkel cell carcinoma of the submental skin. In the harvesting of the flap, the technical modifications recently suggested by Dolivet et al were used in all cases. Furthermore, another technical change has been introduced so creating a new infrahyoid facio‐myocutaneous flap (IHFMCF).

The surgical technique is described in detail.

Results.

No total or partial flap necrosis was experienced. All reconstructions healed quickly without wound complications and with good functional results. The healing process in the donor site was excellent in every case with good aesthetic results.

Conclusions.

The IHFMCF is a versatile, reliable, and convenient flap suitable for repairing small and medium‐sized defects of the oral cavity and oropharynx and obviates the need for a microvascular reconstruction. © 2007 Wiley Periodicals, Inc. Head Neck 29, 2007
Restoration of wild‐type p53 function in human cancer: Relevance for tumor therapy
Authors: Bossi Gianluca , Sacchi Ada
Published: January 2007

Background.

In the majority of human cancers, the tumor suppressor activity of p53 is impaired because of mutational events or interactions with other proteins (ie, MDM2). The loss of p53 function is responsible for increased aggressiveness of cancers, while tumor chemoresistance and radioresistance are dependent upon the expression of mutant p53 proteins.

Methods.

Review of the literature indicates that p53 acts primarily as a transcription factor whose function is subject to a complex and diverse array of covalent post‐translational modifications that markedly influence the expression of p53 target genes responsible for cellular responses such as growth arrest, senescence, or apoptosis. The ability of p53 to induce apoptosis in cancer cells is believed essential for cancer therapy.

Results.

Numerous data indicate that p53 dependent apoptosis is a relevant factor in determining the efficacy of anticancer treatments. Thus, the development of new strategies for restoration of p53 function in human tumors is considered an important issue. Two main approaches for restoration of p53 function have been pursued that impact anticancer treatments: (a) de novo expression of wild‐type p53 (wt‐p53) through gene therapy and (b) identification of small molecules reactivating wt‐p53 function.

Conclusions.

The extensive body of knowledge acquired has identified manipulations of p53 signaling as a relevant issue for successful therapies. In this context, the recognition of p53 status in cancer cells is significant and would help considerably in the selection of an appropriate therapeutic approach. p53 manipulations for cancer therapy have revealed the need for specificity of p53 activation and ability to spare body tissues. Furthermore, the promising results obtained by using molecules competent to reactivate wt‐p53 functions in cancer cells provide the basis for the design of new molecules with lower side effects and higher anti‐tumor efficiency. The reexpression and reactivation of p53 protein in human cancer cells would increase tumor susceptibility to radiation or chemotherapy enhancing the efficacy of standard therapeutic protocols. © 2007 Wiley Periodicals, Inc. Head Neck 29, 2007
Multiple intraosseous hemangiomas—investigation and role of N‐butylcyanoacrylate in management
Authors: Syal Rajan , Tyagi Isha , Goyal Amit , Barai Sukanto , Parihar Anit
Published: January 2007

Background.

Primary intraosseous hemangiomas are rare (0.7% of all osseous neoplasms), benign, slow‐growing neoplasms. These lesions are usually solitary. We are reporting a case of multicentric intraosseous hemangiomas. Investigation, treatment options, and role of N‐butylcyanoacrylate (NBCA) in management will be discussed.

Methods and Results.

A 20‐year‐old man had multicentric intraosseous hemangiomas involving the skull bones, mandible, vertebra, pelvic bone, and tibial tuberosity. N‐butylcyanoacrylate was used by direct puncture technique using a transosseous transcutaneous route to control profuse bleeding from the retromolar region.

Conclusion.

To the best of our knowledge, this is the first reported case with such extensive multicentric intraosseous hemangiomas. N‐butylcyanoacrylate by direct puncture technique can be an effective method to devascularize and stabilize low‐flow intraosseous vascular tumors. © 2007 Wiley Periodicals, Inc. Head Neck, 2007
Epithelioid osteosarcoma presenting as a rapidly expanding maxillary mass
Authors: Rinaggio Joseph , Kewitt Greg F. , McGuff H. Stan
Published: January 2007

Background.

Osteosarcomas of the jaws account for less than 10% of reported neoplasms of this type. Patients with osteosarcoma in this region tend to be in the late‐third to mid‐fourth decades of life. The osteoblastic, chondroblastic, and fibroblastic variants constitute the majority of lesions.

Methods.

A mass was observed in the maxilla of a 50‐year‐old male who presented for a complete odontectomy. Over the ensuing weeks, the mass substantially increased in size, despite multimodality treatment efforts.

Results.

Radiographic findings revealed a mixed density mass of the left maxilla. Histologic, immunohistochemical, and electron microscopy examination of the tumor showed a malignant mesenchymal neoplasm consisting of sheets of epithelioid and spindle cells exhibiting focal osteoid formation.

Conclusions.

We report a rare and aggressive case of epithelioid osteosarcoma arising in the maxillofacial complex. © 2007 Wiley Periodicals, Inc. Head Neck, 2007
Twist, a novel oncogene, is upregulated in pancreatic cancer: Clinical implication of Twist expression in pancreatic juice
Authors: Ohuchida Kenoki , Mizumoto Kazuhiro , Ohhashi Seiji , Yamaguchi Hiroshi , Konomi Hiroyuki , Nagai Eishi , Yamaguchi Koji , Tsuneyoshi Masazumi , Tanaka Masao
Published: January 2007

Despite evidence that Twist, a highly conserved basic helix‐loop‐helix transcription factor, is a novel oncogene, there are no reports describing Twist expression in pancreatic cancer. Intraductal papillary mucinous neoplasm (IPMN) and pancreatic intraepithelial neoplasia (PanIN) are precursor lesions of pancreatic cancer. To clarify involvement of Twist expression in pancreatic cancer, we used quantitative reverse transcription‐polymerase chain reaction and examined Twist expression in pancreatic cancer, IPMN, and non‐neoplastic pancreas using bulk tissues (11 cancers, 18 IPMNs, and 15 non‐neoplastic pancreata), microdissected cells (cancer from 22 sections, IPMN from 19 sections, PanIN from 6 sections, and pancreatitis‐affected epithelial cells from 14 sections), and pancreatic juice (16 from cancer, 28 from IPMN, and 17 from pancreatitis). Twist expression differed significantly between cancer and IPMN bulk tissues (p < 0.0001) but not between cancer and non‐neoplastic tissues. Twist expressions differed significantly between microdissected cancer cells, IPMN cells, and pancreatitis‐affected cells (all comparisons, p < 0.017). PanIN cells expressed significantly lower levels of Twist than did IDC cells (p = 0.016). Twist expression differed significantly between cancer and IPMN juice samples (p = 0.0002) but not between cancer and pancreatitis juice samples. Receiver operation characteristic curve analyses revealed that measurement of Twist was more useful for discriminating cancer from IPMN than from chronic pancreatitis (p = 0.009). Our results suggest that Twist is involved in tumor progression of pancreatic cancer and that measurement of Twist in pancreatic juice may be useful to differentiate pancreatic cancer from nonmalignant neoplasms such as IPMN. © 2007 Wiley‐Liss, Inc.
Combined analysis of HPV‐DNA, p16 and EGFR expression to predict prognosis in oropharyngeal cancer
Authors: Reimers Niklas , Kasper Hans U. , Weissenborn Soenke J. , Stützer Hartmut , Preuss Simon F. , Hoffmann Thomas K. , Speel Ernst Jan M. , Dienes Hans P. , Pfister Herbert J. , Guntinas‐Lichius Orlando , Klussmann Jens P.
Published: January 2007

Molecular prognostic indicators for oropharyngeal squamous cell carcinoma (OSCC), including HPV‐DNA detection, epidermal growth factor receptor (EGFR) and p16 expression, have been suggested in the literature, but none of these are currently used in clinical practice. To compare these predictors, 106 newly diagnosed OSCC for the presence of HPV‐DNA and expression of p16 and EGFR were analyzed. The 5‐year disease‐free survival (DFS) and overall survival (OS) were calculated in relation to these markers and a multivariate Cox analysis was performed. Twenty‐eight percent of the cases contained oncogenic HPV‐DNA and 30% were positive for p16. The p16 expression was highly correlated with the presence of HPV‐DNA (p < 0.001). Univariate analysis of the 5‐year DFS revealed a significantly better outcome for patients with p16‐positive tumors (84% vs. 49%, p = 0.009). EGFR‐negative tumors showed a tendency toward a better prognosis in DFS (74% vs. 47%, p = 0.084) and OS (70% vs. 45%, p = 0.100). Remarkable and highly significant was the combination of p16 and EGFR expression status, leading to 5‐year DFS of 93% for p16+/EGFR− tumors vs. 39% for p16−/EGFR+ tumors (p = 0.003) and to a 5‐year OS of 79% vs. 38%, respectively (p = 0.010). In multivariate analysis p16 remained a highly significant prognostic marker for DFS (p = 0.030) showing a 7.5‐fold increased risk for relapse in patients with p16‐negative tumors. Our data indicate that p16 expression is the most reliable prognostic marker for OSCC and further might be a surrogate marker for HPV‐positive OSCC. HPV+/p16+ tumors tended to have decreased EGFR expression, but using both immunohistological markers has significant prognostic implications. © 2007 Wiley‐Liss, Inc.
Expression of centrosome‐associated gene products is linked to tetraploidization in mantle cell lymphoma
Authors: Neben Kai , Ott German , Schweizer Silja , Kalla Jörg , Tews Björn , Katzenberger Tiemo , Hahn Meinhard , Rosenwald Andreas , Ho Anthony D. , Müller‐Hermelink Hans Konrad , Lichter Peter , Krämer Alwin
Published: January 2007

In mantle cell lymphoma (MCL), a blastoid variant with a striking tendency to harbor chromosome numbers in the tetraploid range has been identified. Centrosome aberrations have recently been implicated in the induction of aneuploidy in many human malignancies including MCL by malsegregation of chromosomes during anaphase of mitosis. Recently, we showed that centrosome aberrations occur more frequently in tetraploid MCL as compared to their diploid counterparts. To test the hypothesis of an association between tetraploidization and expression of genes coding for centrosomal proteins in MCL, tumor RNA of 33 MCL samples was hybridized to custom‐made cDNA microarrays, representing 4,628 distinct human gene‐specific fragments, with particular enrichment for cancer‐relevant (n = 2,440) and centrosome‐associated genes (n = 359). Notably, 4 of the 6 most significant genes (CAMKK2, PCNT2, TUBGCP3, TUBGCP4) discriminating between diploid and near‐tetraploid MCL code for centrosomal proteins. As confirmed by quantitative RT‐PCR analysis, calcium/calmodulin‐dependent protein kinase II (CAMKK2), pericentrin (PCNT2) and γ‐tubulin complex associated protein 3 (TUBGCP3) were all found to be significantly higher expressed in near‐tetraploid than in diploid MCL samples. In conclusion, we describe a comprehensive expression signature of a set of genes associated with tetraploidization in MCL. The high expression level of centrosome‐associated gene products in blastoid MCL matches the description of more frequent centrosome aberrations in this MCL variant. © 2007 Wiley‐Liss, Inc.
Management of early breast cancer in the elderly
Authors: Rao Vittal S.R. , Garimella Veerabhadra , Hwang Meiju , Drew Philip J.
Published: January 2007

Breast cancer is the most common malignancy in women with an age related increase in incidence ranging from 1 in 50 at age 50 to 1 in 10 at age 80. This is particularly significant in view of the changing demographics in the western population, characterised by an aging population and increased life expectancy. However in spite of favourable prognostic factors and less aggressive biological behaviour, elderly breast cancer patients receive less aggressive treatment when compared with their younger counterparts. Appropriate treatment should be offered depending on physiological reserve and comorbidities. Primary endocrine treatment has been shown to be associated with significant morbidity in terms of disease progression. Prompt surgery and adjuvant treatment can decrease relapse and improve survival. Radiation therapy is shown to decrease local relapse and chemotherapy may have a role in a select group of patients with adverse prognostic factors. With incidence of breast cancer bound to increase in the elderly population, it is essential to establish optimum therapy in this cohort of patients as studies reveal good outcome from standard treatment. © 2007 Wiley‐Liss, Inc.
Biomimetic interfacial interpenetrating polymer networks control neural stem cell behavior
Authors: Saha Krishanu , Irwin Elizabeth F. , Kozhukh Julia , Schaffer David V. , Healy Kevin E.
Published: January 2007

Highly‐regulated signals surrounding stem cells, such as growth factors at specific concentrations and matrix mechanical stiffness, have been implicated in modulating stem cell proliferation and maturation. However, tight control of proliferation and lineage commitment signals is rarely achieved during growth outside the body, since the spectrum of biochemical and mechanical signals that govern stem cell renewal and maturation are not fully understood. Therefore, stem cell control can potentially be enhanced through the development of material platforms that more precisely orchestrate signal presentation to stem cells. Using a biomimetic interfacial interpenetrating polymer network (IPN), we define a robust synthetic and highly‐defined platform for the culture of adult neural stem cells. IPNs modified with two cell‐binding ligands, CGGNGEPRGDTYRAY from bone sialoprotein [bsp‐RGD(15)] and CSRARKQAASIKVAVSADR from laminin [lam‐IKVAV(19)], were assayed for their ability to regulate self‐renewal and differentiation in a dose‐dependent manner. IPNs with >5.3 pmol/cm2 bsp‐RGD(15) supported both self‐renewal and differentiation, whereas IPNs with lam‐IKVAV(19) failed to support stem cell adhesion and did not influence differentiation. The IPN platform is highly tunable to probe stem cell signal transduction mechanisms and to control stem cell behavior invitro. © 2007 Wiley Periodicals, Inc. J Biomed Mater Res, 2007
Influence of O2‐carrying plasma hemoprotein “albumin‐heme” on complement system and platelet activation in vitro and physiological responses to exchange transfusion
Authors: Komatsu Teruyuki , Huang Yubin , Wakamoto Shinobu , Abe Hideki , Fujihara Mitsuhiro , Azuma Hiroshi , Ikeda Hisami , Yamamoto Hisashi , Horinouchi Hirohisa , Kobayashi Koichi , Tsuchida Eishun
Published: January 2007

Recombinant human serum albumin (HSA) including the synthetic iron(II)‐porphyrin (FeP), albumin‐heme (HSA‐FeP), is a unique O2‐carrying plasma hemoprotein as a red blood cell substitute. We have investigated the possible influence of HSA‐FeP on the complement system and platelet activation in vitro. The amounts of the serum complement titer CH50 and terminal complement complex SC5b‐9 of human blood serum, incubated with HSA‐FeP (10, 20, and 40 vol %), were almost the same as those of the corresponding samples with HSA. The effect of HSA‐FeP on the platelet reactivity has been demonstrated by conformational changes in the membrane glycoprotein IIb/IIIa and surface expression of an α‐granule membrane protein P‐selectin. Platelet activation in response to the ADP‐stimulation was not influenced by the presence of HSA‐FeP. It can be concluded that the albumin‐heme solution does not facilitate the immunological reaction and platelet activation. Moreover, a 20% exchange transfusion with HSA‐FeP into anesthetized rats has been performed to evaluate the circulation and blood parameters for 6 h. Time course changes in all parameters showed features identical to the control group (without infusion) and HSA group. © 2007 Wiley Periodicals, Inc. J Biomed Mater Res, 2007
Cell growth and detachment from protein‐coated PNIPAAm‐based copolymers
Authors: Moran Martin T. , Carroll William M. , Selezneva Irina , Gorelov Alexander , Rochev Yuri
Published: January 2007

The cultivation of cells requires the use of unfavorable proteolytic enzymes, which cause cell‐surface modification and also need considerable optimization. Recently, with the development of smart polymers, research has looked to using thermoresponsive polymers as cell culture substrates. These novel surfaces allow the cultivation of cells without using enzymes by utilizing the thermoresponsive phase transition property of poly(N‐isopropylacrylamide) (PNIPAAm). Copolymers of PNIPAAm and N‐tert‐butyl‐acrylamide (NtBAm) with varying ratios were synthesized and solvent cast. The copolymer films are coated with cell adhesion promoters such as collagen, poly‐L‐lysine, and laminin to increase their cell adhesion and growth properties. Cell activity measured by the alamarBlue™ and PicoGreen® assays is similar for coated copolymer films and standard tissue culture plastic controls. Deposition of cell adhesion promoters onto the copolymer films was characterized by scanning electron microscopy (SEM) and atomic force microscopy (AFM). Cell detachment from the copolymer films is dependent on copolymer composition and is not affected by the surface coatings of extracellular matrix (ECM) proteins. The results demonstrate a versatile method for the cultivation of cells while eliminating the need for the use of digestive enzymes such as trypsin. © 2007 Wiley Periodicals, Inc. J BiomedMater Res 2007
Plasma‐deposited tetraglyme surfaces greatly reduce total blood protein adsorption, contact activation, platelet adhesion, platelet procoagulant activity, and in vitro thrombus deposition
Authors: Cao Lan , Chang Mark , Lee Chi‐Ying , Castner David G. , Sukavaneshvar Sivaprasad , Ratner Buddy D. , Horbett Thomas A.
Published: January 2007

The ability of tetraethylene glycol dimethyl ether (tetraglyme) plasma deposited coatings exhibiting ultralow fibrinogen adsorption to reduce blood activation was studied with six in vitro methods, namely fibrinogen and von Willebrand's factor adsorption, total protein adsorption, clotting time in recalcified plasma, platelet adhesion and procoagulant activity, and whole blood thrombosis in a disturbed flow catheter model. Surface plasmon resonance results showed that tetraglyme surfaces strongly resisted the adsorption of all proteins from human plasma. The clotting time in the presence of tetraglyme surfaces was lengthened compared with controls, indicating a lower activation of the intrinsic coagulation cascade. Platelet adhesion and thrombin generation by adherent platelets were greatly reduced on tetraglyme‐coated materials, compared with uncoated and Biospan®‐coated glass slides. In the in vitro disturbed blood flow model, tetraglyme plasma coated catheters had 50% less thrombus than did the uncoated catheters. Tetraglyme‐coated materials thus had greatly reduced blood interactions as measured with all six methods. The improved blood compatibility of plasma‐deposited tetraglyme is thus not only due to their reduced platelet adhesion and activation, but also to a generalized reduction in blood interactions. © 2007 Wiley Periodicals, Inc. J Biomed Mater Res 2007
Transmural communication at a subcellular level may play a critical role in the fallout based‐endothelialization of dacron vascular prostheses in canine
Authors: Zhang Ze , Briana Stephen , Douville Yvan , Zhao Hugh , Gilbert Nathalie
Published: January 2007

A microporous and permeable wall is important for the healing of vascular prostheses, however, the significance of its permeability to soluble substances at subcellular level has not been demonstrated. Polyester arterial prostheses were prepared in such a way that each of them contained three segments, of which at least one segment was impervious and another segment was permeable to water but impermeable to cells. Twenty graft segments were implanted in 7 dogs as a thoraco–abdominal bypass for 2 months. The prostheses were then harvested, photographed, and treated for histological and morphological studies. The low porosity graft capped by two thrombogenic segments was fully endothelialized, proving the fallout mechanism. The striking contrast with its impermeable counterpart demonstrated that a wall permeable to small substances of subcellular level was critical for the endothelial healing. A wide range of water permeabilities did not reveal advantages of high water permeable segments over low water permeable ones. Endothelial ingrowth from anastomoses was also jeopardized in the absence of wall permeability. In conclusion, transmural communication at a subcellular level may have played a critical role in the fallout based‐endothelialization of arterial prostheses in canine. This highlights the potential function of perigraft cytokines and growth factors in endothelial healing. © 2007 Wiley Periodicals, Inc. J Biomed Mater Res, 2007
Ectopic and in situ bone formation of adipose tissue‐derived stromal cells in biphasic calcium phosphate nanocomposite
Authors: Lin Yunfeng , Wang Tao , Wu Ling , Jing Wei , Chen Xizhe , Li Zhiyong , Liu Lei , Tang Wei , Zheng Xiaohui , Tian Weidong
Published: January 2007

Adipose‐derived stromal cells (ASCs) have the potential to differentiate into a variety of cell lineages both in vitro and in vivo. A novel biodegradable biphasic calcium phosphate nanocomposite (NanoBCP) comprising β‐tricalcium phosphate matrix and hydroxyl apatite nanofibers is favorable for bone tissue engineering. In this study, ASCs were harvested from Sprague‐Dawley (SD) rats and induced to osteogenesis before seeded into porous NanoBCP scaffold. To determine ectopic in vivo osteogenic differentiation, these constructs were implanted in nude mice subcutaneously. Meanwhile, the ability of engineered constructs to stimulate in situ bone repair was assessed in rat critical‐size cranial defects. The defects were filled with NanoBCP containing osteogenic ASCs in experimental group; with cell‐free NanoBCP in negative controls; and with nothing in blank controls. The retrieved specimens were analyzed with morphological, histological, and molecular methods. Histological analysis of the retrieved specimens from nude mice in experimental group showed obvious ectopic bone formation. There were positive expression of osteopontin (OPN) and osteocalcin (OCN) at RNA and protein level. As for the cranial defects, there was complete repair in experimental group, but only partial repair in negative controls. The radiographs, H&E staining, and Masson's trichrome method showed better bone regeneration at experimental sites. Combining osteogenic ASCs with NanoBCP can lead to formation of ectopic new bone. Furthermore, the approach can also stimulate bone regeneration and repair for the large size bone defects. © 2007 Wiley Periodicals, Inc. J Biomed Mater Res, 2007
Formation of the chondrocranium of Trachemys scripta (Reptilia: Testudines: Emydidae) and a comparison with other described turtle taxa
Authors: Tulenko Frank J. , Sheil Christopher A.
Published: January 2007

Few descriptions of the formation of the chelonian chondrocranium exist. Herein, developmental stages critical to the formation of the chondrocranium of the Red‐eared Slider, Trachemys scripta (Testudines: Emydidae), are described and illustrated, with particular attention given to ontogenetic changes that take place in the orbitotemporal region of the skull. Morphological descriptions are based on cleared and double‐stained and serially‐sectioned embryos. These specimens allowed for a detailed evaluation of the developmental morphology of the trabeculae, interorbital septum, pilae metoptica, taeniae marginalis, acrochordal cartilage, pilae antotica, parachordal cartilages, and crista sellaris. Additionally, the formation of the chondrocranium of T. scripta is compared to those of Chrysemys picta (Emydidae) and Caretta caretta (Chelonidae). Overall, the patterns of formation and remodeling of the chondrocranium are quite similar among these species, with the most conspicuous differences observed in remodeling of the posterior orbital cartilages (specifically, the pila metoptica). Reorganization of these cartilages is discussed briefly in the context of associated extraocular muscles for T. scripta and C. caretta. A prominent intertrabecula is reported in T. scripta, supporting previous observations of this structure in emydid turtles. J. Morphol., 2007. © 2007 Wiley‐Liss, Inc.
Ultrastructure and tubulin immunocytochemistry of the copulatory stylet‐like structure in Childia species (Acoela)
Authors: Tekle Yonas I. , Raikova Olga I. , Justine Jean‐Lou , Jondelius Ulf
Published: January 2007

One of the main characters used in acoel taxonomy is the male copulatory organ. Despite this, ultrastructural studies of this structure are scarce. We studied the ultrastructure of the copulatory organ in eight species of acoels belonging to the taxon Childia. Members of Childia possess a well‐developed conical or cylindrical stylet‐like structure composed of needles. Immunogold cytochemistry of tubulin was used to determine the composition of the needles. Stylet‐like structures of Childia species at the ultrastructural level are basically similar. Stylet needles show intracellular differentiations. As shown both by ultrastructural and immunocytochemical methods, the stylet needles, in all species studied, are composed of long, parallel microtubules, either tightly packed or polymerized. We report unusual polymerization of microtubules, resulting in formation of a honeycomb‐like structure in cross section. Variations of ultrastructure among Childia species include numbers and arrangement of stylet needles, shape of needles, needle compactness, microtubule polymerization, direction of stylet growth, and presence/absence of different types of granules. The stylet‐like structures are homologous within Childia, but are likely to prove nonhomologous with the other needle‐like structures found in acoel copulatory organs. Stylets in Platyhelminthes are not homologous with stylet‐like structures in acoels. J. Morphol., 2007. © 2007 Wiley‐Liss, Inc.
An assessment of ‘international best practice’ in visitor attraction management: does Scotland really lag behind?
Authors: Garrod Brian , Leask Anna , Fyall Alan
Published: January 2007

This paper compares and contrasts selected management practices among visitor attractions in Scotland, Australia, Canada and New Zealand. The catalyst for the study was the growing perception that management practices among visitor attractions in Scotland are becoming increasingly outdated and that the sector needs to learn from ‘international best practice’ in this respect. A postal questionnaire was sent to all paid‐admission visitor attractions in the four countries. In total, 1022 visitor attractions replied, representing an overall response rate of 41%. Chi‐square analysis was then used to test various hypotheses relating to the uptake of these management practices. A key conclusion is that although management practices do vary significantly among the four countries, Scotland does not necessarily lag behind. Indeed, Scottish visitor attractions seem to lead the way in many respects. Meanwhile, the study finds no strong evidence to suggest that visitor attractions in the other three countries have indeed identified and are following a common ‘international best practice’. Copyright © 2007 John Wiley & Sons, Ltd.
Investigation of wear mechanism by organic sulphides in vegetable oils
Authors: Minami Ichiro , Kubo Tomoo , Shimamoto Daisuke , Takahashi Daisuke , Nanao Hidetaka , Mori Sigeyuki
Published: January 2007

Tribological properties of organic sulphides in esters were examined under boundary conditions. Magnification of wear by sulphides was observed in unsaturated esters. A dumb‐bell‐shaped wear scar, composed of a ‘central area’ and a ‘border area’, was found as an intermediate of wear growth. The ‘border area’ then expanded, resulting in a large wear scar. An induction period was observed before the generation of the ‘border area’. Influences of additive concentration on the induction period were also observed. Surface analyses of worn surfaces revealed that organic oxides, sulphides (unreacted additive) and sulphoxides are present in the boundary film. Influence of auto‐oxidation of the base oil on wear mechanism was proposed. Copyright © 2007 John Wiley & Sons, Ltd.
Modeling the Cure of an Epoxy‐Amine Resin with Bisphenol A as an External Catalyst
Authors: Perrin François‐Xavier , Nguyen Thi Minh Hanh , Vernet Jean‐Louis
Published: January 2007

The cure kinetics of a DGEBF/DGEBA mixture with a commercial aliphatic amine mixture [poly(propylene) oxide diamine D230 and diethylene triamine (DETA)] was investigated by DSC. Two types of kinetic models based upon the formation of amine‐epoxy‐hydroxyl transition complex without or with fast pre‐equilibria have been tested and discussed. The mechanistic model with pre‐equilibria was based on the existence of two different epoxy‐hydroxyl complexes namely one involving hydroxyl groups of BPA and the other, the hydroxyl groups of polymer chains. All the kinetic and thermodynamic parameters have been evaluated and discussed. The results show that the mechanistic model with pre‐equilibria determined from isothermal cure provide a more reasonable fitting of the polymerization kinetics under programmed heating‐rate modes than Horie's model. Moreover, the former kinetic model allows the prediction of changes in the BPA content of the initial formulation with good accuracy.

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Mechanistic Investigations on a Diynone Type Photoinitiator
Authors: Seidl Bernhard , Liska Robert
Published: January 2007

Recently, it has been shown that 1,5‐diphenyl‐penta‐1,4‐diyn‐3‐one (DPD) has some surprising characteristics as photoinitiator for free radical polymerization. In the present investigations we focused on the photochemistry in hydrogen donating isopropyl alcohol (IPA) and neutral acetonitrile (MeCN). HPLC and column chromatographic separation were applied for photoproduct identification. Different types of radical quenchers such as the stable radical TEMPO and the non‐polymerizable monomer methyl t‐butacrylate (t‐BAM) were also used to identify the initiating species. In IPA, fast hydrogen abstraction reaction similar to that of benzophenone was found, whereas the hydrogen donor is the initiating molecule. Significantly, slower 2 + 2 cycloaddition reaction involving the carbonyl group is the predominant pathway in MeCN. Experiments with t‐BAM indicated that DPD is directly responsible for the initiation process.

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Lower Critical Solution Temperature Properties of N‐Isopropylacrylamide‐Based Pseudopolyrotaxanes by Complexation with Cucurbituril[6]
Authors: Choi Soo Whan , Ritter Helmut
Published: January 2007

Pseudopolyrotaxanes 4a and 5a are synthesized by two paths: a) directly from the pseudorotaxane, and b) by complexing with cucurbituril (CB[6]) in water at room temperature after the polymerization. Free radical copolymerization with CB[6] (un)complexed monomer and N‐isopropylacrylamide (NIPAAM) is carried out using a redox initiator in aqueous media at room temperature. The properties of pesudorotaxanes (4a and 5a) and polymers (4 and 5) are investigated by TGA, DSC, and turbidity measurements. The lower critical solution temperatures of the NIPAAM‐containing copolymers and CB[6] are significantly higher than those of pure NIPAAM copolymers. The pseudopolyrotaxanes 4a and 5a have a higher thermal stability, as a result of threading of the CB[6] rings onto the polymer side groups.

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Formation of martensite in 304 grade stainless steels and their welds
Authors: Michler T.
Published: January 2007

The formation of martensite in metastable austenitic stainless steels was investigated. The results showed that the formation of martensite in 304 grade stainless steels due to the exposure to cryogenic temperatures is negligible. The amount of formed martensite is dependent on the chemical composition of the actual heat but for standard grades the amount is not expected to exceed a very few percent. In welds the formation of martensite is not promoted by the presence of δ‐ferrite. The formation of martensite due to cold forming at room temperature can reach around 20 %. Cold forming with subsequent exposure to cryogenic temperatures does not lead to additional formation of martensite due to the exposure to low temperatures. Cold forming at low temperatures leads to the highest amount of martensite formed in metastable stainless steels.
Low Heat Welding of Titanium Materials with a Pulsed Nd:YAG Laser
Authors: Richter K. , Behr W. , Reisgen U.
Published: January 2007

Titanium materials exhibit a property profile that is just as versatile as that of steel materials. Titanium materials therefore have outstanding properties, such as excellent resistance to corrosion and high strength values at low densities, which makes them ideal for use in the chemical industry and as structural materials in lightweight construction.

Due to the high affinity of titanium to atmospheric gases at increased temperatures above 500 °C, titanium components have to be welded in a sophisticated process under inert shielding gas by TIG welding or by an electron beam in a vacuum.

A novel innovative laser beam welding process using a pulsed laser with free pulse shaping will be presented here with which oxidation‐free titanium weld seams with excellent mechanical and technological properties can be produced. For this low heat welding process, the otherwise commonly used inert gas covering can be substituted with a shielding gas nozzle. The process‐specific low heat input and the resulting low energy input per unit length both have a positive effect on the microstructure and thus on the mechanical properties.

This welding process offers both technological and economical advantages over the processes used up until now, particularly for the machining of complex components and for series production.
Impact of copper on the induction and repair of oxidative DNA damage, poly(ADP‐ribosyl)ation and PARP‐1 activity
Authors: Schwerdtle Tanja , Hamann Ingrit , Jahnke Gunnar , Walter Ingo , Richter Constanze , Parsons Jason L. , Dianov Grigory L. , Hartwig Andrea
Published: January 2007

Copper is an essential trace element involved, among other functions, in enzymatic antioxidative defense systems. However, nonprotein bound copper ions have been shown to generate reactive oxygen species. To gain insight into the discrepancy between the protective properties of copper on the one hand and its toxicity on the other hand, we examined the genotoxic effects of CuSO4in cultured human cells. Here we report that copper, at cytotoxic concentrations, induces oxidative DNA base modifications and DNA strand breaks. However, at lower noncytotoxic concentrations, copper inhibits the repair of oxidative DNA damage induced by visible light. As a first mechanistic hint, inhibition of H2O2‐induced poly(ADP‐ribosyl)ation was identified in cultured cells and further experiments demonstrated a strong inhibition of the activity of isolated poly(ADP‐ribose)polymerase‐1 (PARP‐1) by copper. Bioavailability studies of copper showed a dose‐dependent uptake in cells and pointed out the relevance of the applied concentrations. Taken together, the results indicate that copper, under conditions of either disturbed homeostasis or overload due to high exposure, exerts defined genotoxic effects. Hence, a balance needs to be maintained to ensure sufficient uptake and to prevent overload.
Fecal water from ileostomic patients consuming oat β‐glucan enhances immune responses in enterocytes
Authors: Ramakers Julian D. , Volman Julia J. , Biörklund Maria , Önning Gunilla , Mensink Ronald P. , Plat Jogchum
Published: January 2007

Yeast, fungal, and dietary β‐glucans have immune‐modulating effects in vitro and in vivo, as thought, mainly by affecting leukocytes; however, effects of oat β‐glucan on enterocytes have never been studied. As recognized, supplying oat β‐glucans as such to cells in culture directly is difficult because of solubility problems. Therefore, six ileostomic patients consumed, in random order, a control diet or an oat β‐glucan enriched diet (5 g) and from the collected ileostomic content, fecal water was prepared and added to two small intestinal cell lines (INT407, Caco‐2) and two colon cell lines (HT29, T84) together with a cytokine cocktail (IL‐1β + INFγ + TNFα). Several parameters reflecting immune‐modulation were measured. As compared to placebo fecal water, β‐glucan enriched fecal water significantly increased IL‐8 production in HT29 (5.0%; p = 0.046) and INT407 cells (22.0%; p = 0.028). Intercellular adhesion molecule (ICAM)‐1 expression increased in T84 (11.0%; p = 0.028) and Caco‐2 cells (20.4%; p = 0.075). These immune‐stimulating effects were confirmed by enhancement of inflammatory expression profiles, as determined with an antibody array. Our findings show immune enhancement by fecal water from ileostomic patients consuming oat β‐glucan both in small intestinal and colon cell lines after stimulation, which is in agreement with documented effects in leukocytes. Whether these immune‐stimulating effects on enterocytes contribute to the enhanced protection of the host against invading pathogens as observed both in animals and in humans, as well as the underlying mechanism, needs further evaluation.
Acrylamide levels in Finnish foodstuffs analysed with liquid chromatography tandem mass spectrometry
Authors: Eerola Susanna , Hollebekkers Koen , Hallikainen Anja , Peltonen Kimmo
Published: January 2007

Sample clean‐up and HPLC with tandem mass spectrometric detection (LC‐MS/MS) was validated for the routine analysis of acrylamide in various foodstuffs. The method used proved to be reliable and the detection limit for routine monitoring was sensitive enough for foods and drinks (38 μg/kg for foods and 5 μg/L for drinks). The RSDs for repeatability and day‐to‐day variation were below 15% in all food matrices. Two hundred and one samples which included more than 30 different types of food and foods manufactured and prepared in various ways were analysed. The main types of food analysed were potato and cereal‐based foods, processed foods (pizza, minced beef meat, meat balls, chicken nuggets, potato‐ham casserole and fried bacon) and coffee. Acrylamide was detected at levels, ranging from nondetectable to 1480 μg/kg level in solid food, with crisp bread exhibiting the highest levels. In drinks, the highest value (29 μg/L) was found in regular coffee drinks.
Dose–response feeding study of short chain chlorinated paraffins (SCCPs) in laying hens: Effects on laying performance and tissue distribution, accumulation and elimination kinetics
Authors: Ueberschär Karl‐Heinz , Dänicke Sven , Matthes Siegfried
Published: January 2007

Technical short chain chlorinated paraffins (C10–C13 with 60% chlorine) were fed to 93 laying hens from 24 to 32 weeks of age in increasing concentrations of up to 100 mg/kg feed. No significant influence on health, relative organ weights or performance (laying intensity, egg weight, feed consumption) was noted. The chlorinated paraffin content of the tissues was linearly related to the concentration of short chain paraffins of the feed. The highest concentrations were found in abdominal fat, egg yolk and fatty tissues. Breast muscle, egg albumen and bile fluid contained minimal or no residues. Less than 1% of the chlorinated paraffins ingested were incorporated into the body (without head, feet, gut and feathers), whereas about 1.5% were eliminated with the egg yolk and 30% were excreted with urine and faeces. A six‐week kinetic depuration study revealed a biphasic elimination with half‐lifes of 4–40 min (liver, kidneys, legs, fat, blood) for the initial rapid phase, and 15–30 days (blood, fat, liver, yolk, kidneys, legs) for the terminal slow phase.
Museum pricing: challenges to theory development and practice
Authors: Rentschler Ruth , Hede Anne‐Marie , White Tabitha R.
Published: January 2007

The museum sector has undergone considerable change in the last few decades, which has been a result of both internal and external forces. The topic of pricing in museums, however, has attracted little interest from researchers in the field despite the sector's need to understand it better. This study aimed to address this gap in knowledge. Results of a comprehensive literature review on pricing highlight that the topic of pricing in museums is problematic, as a range of issues, social, political and often value‐laden, must be considered before pricing decisions can be made. The study highlights that there is diversity in the sector with regard to pricing, but that museums generally adopt a unilateral approach to pricing. Researchers in entrepreneurial marketing have noted that conventional pricing theory is being turned on its head and they argue that deciding what prices to charge represents one of the more entrepreneurial strategies for organisations. This study indicates that, within the context of museums, marketers are failing to recognise and capitalise on such pricing opportunities. Approaches to setting multiple museum pricing strategies, depending on the market context, are proposed in this paper. In this way, knowledge of museum pricing can optimise the organisational outcomes of museums while continuing to meet their social responsibilities.

Copyright © 2007 John Wiley & Sons, Ltd.