bluuebunny/crossref_metadata_2025_split huggingface dataset:
Purpose and regulation of stem cells: a systems‐biology view from the Caenorhabditis elegans germ line
Authors: Cinquin Olivier 
Published: November 2008

AbstractStem cells are expected to play a key role in the development and maintenance of organisms, and hold great therapeutic promises. However, a number of questions must be answered to achieve an understanding of stem cells and put them to use. Here I review some of these questions, and how they relate to the model system provided by the Caenorhabditis elegans germ line, which is exceptional in its thorough genetic characterization and experimental accessibility under in vivo conditions. A fundamental question is how to define a stem cell; different definitions can be adopted that capture different features of interest. In the C. elegans germ line, stem cells can be defined by cell lineage or by cell commitment (‘commitment’ must itself be carefully defined). These definitions are associated with two other important questions about stem cells: their functions (which must be addressed following a systems approach, based on an evolutionary perspective) and their regulation. I review possible functions and their evolutionary groundings, including genome maintenance and powerful regulation of cell proliferation and differentiation, and possible regulatory mechanisms, including asymmetrical division and control of transit amplification by a developmental timer. I draw parallels between Drosophila and C. elegans germline stem cells; such parallels raise intriguing questions about Drosophila stem cells. I conclude by showing that the C. elegans germ line bears similarities with a number of other stem cell systems, which underscores its relevance to the understanding of stem cells. Copyright © 2008 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.
Parental needs for information related to neurocognitive late effects from pediatric cancer and its treatment
Authors: Trask Christine L. , Welch Jennifer J. Greene , Manley Peter , Jelalian Elissa , Schwartz Cindy L. 
Published: November 2008

AbstractBackgroundParents' needs for information about neurocognitive late effects (NCLE) associated with cancer treatment may differ as to the preferred source, format, timing, and amount of information about potential NCLE from treatment. Parental characteristics, treatment variables, and other risk factors may also modulate the needs for information about NCLE.ProcedureA total of 90 parents completed a series of questionnaires related to their perceived knowledge of NCLE and need for further information about NCLE, coping style, stress, perceived risk for NCLE, and information related to their child's diagnosis and treatment.ResultsThese findings indicate that although parents report feeling knowledgeable about NCLE, they continue to have a need for further information. Many parents would prefer multi‐modal presentation of this material, but they do not have a clear consensus about the optimal time to first discuss this risk. Parents who reported higher levels of emotional distress expressed a preference to receive information earlier. Stepwise regression analyses revealed that parents of children who received cranial radiation reported being well informed about NCLE, whereas parents of children who received chemotherapy reported wanting more information about NCLE.ConclusionsIt is important to recognize the high level of need for information about potential NCLE in caregivers of children with cancer. Further research is needed to understand how to tailor the timing and mode of presentation to individual families. Pediatr Blood Cancer 2009;52:273–279. © 2008 Wiley‐Liss, Inc.
Positron emission tomography in subcutaneous panniculitis‐like T‐cell lymphoma
Authors: Rodriguez Victor R. , Joshi Aparna , Peng Fangyu , Rabah Raja M. , Stockmann Paul T. , Savaşan Süreyya 
Published: November 2008

AbstractSubcutaneous panniculitis‐like T‐cell lymphoma (SPTCL), an uncommon disorder, was diagnosed in a 17‐year‐old female when she presented with multiple hard subcutaneous masses that developed over 3 years. She was treated on chemotherapy consisting of cyclophosphamide, doxorubicin, vincristine, and prednisone. Pre‐ and post‐treatment positron emission tomography study demonstrated dramatic resolution of the subcutaneous lesions indicating its usefulness in SPTCL staging and treatment response monitoring. Pediatr Blood Cancer 2009;52:406–408. © 2008 Wiley‐Liss, Inc.
Aprepitant in adolescent patients for prevention of chemotherapy‐induced nausea and vomiting: A randomized, double‐blind, placebo‐controlled study of efficacy and tolerability
Authors: Gore Lia , Chawla Sant , Petrilli Antonio , Hemenway Molly , Schissel Debra , Chua Vickey , Carides Alexandra D. , Taylor Arlene , DeVandry Suzanne , Valentine Jack , Evans Judith K. , Oxenius Bettina ,   for the Adolescent Aprepitant in Cancer Study Group
Published: November 2008

AbstractBackgroundThe neurokinin‐1 receptor antagonist aprepitant, plus a 5HT3 antagonist and corticosteroid is well‐tolerated and effective in preventing chemotherapy‐induced nausea and vomiting in adults but has not been formally assessed in adolescents.ProcedurePatients age 11–19 years old receiving emetogenic chemotherapy were randomized 2:1 to aprepitant triple therapy (aprepitant [A] 125 mg p.o., dexamethasone [D] 8 mg p.o., and ondansetron [O] 0.15 mg/kg i.v. t.i.d. day 1; A 80 mg, D 4 mg, and O 0.15 mg/kg t.i.d. day 2; A 80 mg and D 4 mg day 3; and D 4 mg day 4) or a control regimen (D 16 mg and O 0.15 mg/kg t.i.d. day 1; D 8 mg and O 0.15 mg/kg t.i.d. day 2; and D 8 mg days 3 and 4). The primary endpoint was the difference in drug‐related adverse events during and for 14 days following treatment. Efficacy and aprepitant pharmacokinetics were assessed.ResultsBaseline characteristics were similar between aprepitant (N = 28) and control (N = 18) groups. Febrile neutropenia was more frequent in the aprepitant group (25% vs. 11.1%). Complete response (CR) rates were 35.7% for aprepitant triple therapy versus 5.6% for the control group. Mean plasma aprepitant AUC0–24 hr and Cmax on day 1 and mean trough concentrations on days 2 and 3 were consistently lower compared to historical data obtained from healthy adults; however, the differences were not clinically significant.ConclusionAprepitant triple therapy was generally well tolerated; CR were greater with aprepitant, although not statistically significant. Pharmacokinetics suggest that the adult dosing regimen is appropriate for adolescents. Pediatr Blood Cancer 2009;52:242–247. © 2008 Wiley‐Liss, Inc.
Intensive chemotherapy for systemic anaplastic large cell lymphoma in children and adolescents: Final results of children's cancer group study 5941
Authors: Lowe Eric J. , Sposto Richard , Perkins Sherrie L. , Gross Thomas G. , Finlay Jonathan , Zwick David , Abromowitch Minnie 
Published: November 2008

AbstractBackgroundAnaplastic large cell lymphoma (ALCL) is characterized by advanced disease at presentation (70–80% of pediatric cases) and accounts for 10–15% of all childhood lymphomas. Treatment strategies for pediatric ALCL vary from short pulse B‐NHL chemotherapy to prolonged leukemia like therapy. The optimal treatment strategy is unknown.MethodsCCG‐5941 used a compressed aggressive multiagent T‐cell lineage chemotherapy regimen consisting of a 3‐week induction therapy (vincristine, prednisone, cyclophosphamide, daunomycin, asparaginase) followed by a 3‐week consolidation period (vincristine, prednisone, etoposide, 6‐thioguanine, cytarabine, asparaginase, methotrexate) followed by six courses of maintenance chemotherapy at 7‐week intervals (cyclophosphamide, 6‐thioguanine, vincristine, prednisone, doxorubicin, asparaginase, methotrexate etoposide, cytarabine). Total therapy was 48 weeks.ResultsEighty‐six children (male 56%, female 44%) with non‐localized ALCL (CD30+) were treated. The majority of tumors were positive for ALK (90%) and of T lineage (83%). Extranodal disease was common (mediastinum 35%, skin 15%, lung 14%, bone 12%, bone marrow 13%, liver 6%, and other viscera 17%). Grade 4 neutropenia occurred in 82% of patients. The 5‐year EFS was 68% (95% CI of 57–78%) and the 5‐year OS was 80% (95% CI of 69–87%). There were 21 relapses and 4 toxic deaths as first events. Relapse occurred early with 17 (81%) relapses occurring within 2 years of diagnosis and 12 (57%) while receiving therapy. Univariate analysis for risk factors only identified bone marrow involvement predicting lower EFS (P = 0.03).ConclusionsCCG‐5941 demonstrated efficacy similar to previously reported regimens but with significant hematologic toxicity. Pediatr Blood Cancer 2009;52:335–339. © 2008 Wiley‐Liss, Inc.
Small cell undifferentiated variant of hepatoblastoma: Adverse clinical and molecular features similar to rhabdoid tumors
Authors: Trobaugh‐Lotrario Angela D. , Tomlinson Gail E. , Finegold Milton J. , Gore Lia , Feusner James H. 
Published: November 2008

AbstractBackgroundSmall cell undifferentiated (SCU) histology in patients with stage I hepatoblastoma (HB) predicts an increased risk of relapse. We sought to determine the significance of SCU histology in patients with unresectable HB.ProcedurePatients enrolled on the pediatric Intergroup (INT0098) trial for HB and patients from the personal consultation files of two of the authors (MF, LG) were reviewed for cases with SCU histology. These patients were compared with SCU HB patients identified by literature review.ResultsEleven patients were studied. All patients with reported AFP results exhibited normal or minimally increased serum AFP levels. None of the patients survived: 10 died of disease progression, and 1 died from treatment complications. Immunostaining revealed that tumors from six of six patients tested were INI1 negative. Cytogenetic and molecular abnormalities in one patient (and two patients from the literature review) were similar to those described in rhabdoid tumors. Comparison with patients from the literature review revealed similar results except that 4 of 29 patients survived without evidence of disease.ConclusionsSCU histology in HB patients is associated with an adverse outcome. These tumors appear to be biologically different from non‐SCU HB. Evaluation of patient characteristics and outcomes for children with SCU HB and/or those with low AFP levels should be determined from large cooperative group studies. In the meantime, we suggest patients with unresectable HB containing SCU elements have careful cytogenetic, molecular, and immunohistochemical evaluation to ascertain rhabdoid features and receive treatment that differs from that provided for other HB patients. Pediatr Blood Cancer 2009;52:328–334. © 2008 Wiley‐Liss, Inc.
Viscoelastic behavior of a polyester resin concrete reinforced with nonmetallic bars under bending loads
Authors: San‐José J. Tomás , Aguado Antonio , Manso Juan M. 
Published: November 2008

AbstractThis article deals with the study of a highly durable polyester polymer concrete reinforced with glass fiber polymer rebars. It describes the specific properties of the concrete, which were tested using different experimental techniques such as porosimetry, scanning electron microscopy, and petrography. Likewise, characterization on a macroscale was carried out to define the mechanical properties of the material (modulus of elasticity, stress–strain curve, ultimate strength, and bond). Having defined these properties, the article then presents a relatively simple calculation method to estimate the ultimate bearing capacity of beams under bending load, which is then verified by testing both beams and full‐scale elements. Bearing in mind the viscoelastic nature of the polymer, several considerations are advanced on the identification of safety factors connected with permanent load (deferred deformations) and live load. POLYM. COMPOS., 2009. © 2008 Society of Plastics Engineers
Self‐lubricating and self‐protecting properties of polymer composites for wear and friction applications
Authors: Quintelier J. , Samyn P. , De Doncker L. , Vermeulen J. , Tuzolana T. , Cardon L. , Ragaert K. , De Baets P. , Degrieck J. 
Published: November 2008

AbstractBased on the well‐known pin‐on‐disc test rig, a new test setup has been developed for online measuring of the wear and friction behavior of polymer matrix composites. Contrasting with a traditional friction and wear test rig, a steel pin and composite disc are presently used to study the influence of wear debris and fiber orientation. This test setup has a main influence on the results. The polymer materials, a thermoset polyester, and a thermoplastic polyphenylene sulfide were reinforced with glass and carbon fibers, respectively. The results show two different promising aspects of “new” materials for wear and friction applications and more specific to different machine components, namely self‐lubricating and self‐protecting ability. The self‐lubricating ability exists from creating a polymer film on the surface which reduces the coefficient of friction, and the self‐protecting behavior is because of the creation of a protecting carbon film on the surface. The self‐lubricating ability depends on the test parameters, while the self‐protecting ability was due to the material and the structure. POLYM. COMPOS., 2009. © 2008 Society of Plastics Engineers
Covalent addition of diethyltoluenediamines onto carbon nanotubes for composite application
Authors: Wang Shiren , Liang Richard , Wang Ben , Zhang Chuck 
Published: November 2008

AbstractDiethyltoluenediamines (DETDA) was grafted to single‐walled carbon nanotubes (SWNTs) through diazonium‐based addition for improving dispersion and interfacial bonding in SWNT/epoxy nanocomposites. Characterization results of Fourier Transformed Infrared spectroscopy and Raman spectroscopy validated covalent bonding between DETDA and carbon nanotubes. The degree of functionalization was about 4% based on thermo‐gravimetric analysis. Interfacial bonding strength was computed in the presence of chemical bonding and the computation results indicated that the interfacial shear strength in the presence of functionalized carbon nanotubes was significantly enhanced. The experimental test revealed that the tensile strength of nanocomposites was enhanced about 23% and Young's modulus about 25%, with 0.5 wt% loading of functionalized‐nanotubes. These considerable improvements further verified the load‐transfer enhancement in the functionalized‐SWNTs/epoxy nanocomposites. POLYM. COMPOS., 2009. © 2008 Society of Plastics Engineers
Role of fillers on three‐body abrasive wear behavior of glass fabric reinforced epoxy composites
Authors: Suresha B. , Chandramohan G. , Mohanram P.V. 
Published: November 2008

AbstractThe article summarizes an experimental study on the abrasive wear behavior of particulate filled glass‐epoxy (G‐E) composites. The two fillers investigated were graphite and alumina. The wear behavior was assessed by rubber wheel abrasion tests. The tests were carried out for 270, 540, 810, and 1080 m abrading distances at 22 and 32 N loads. The worn surfaces were examined using scanning electron microscopy (SEM). The results showed varied responses under different abrading distance because of the addition of fillers in G‐E composites. Graphite filler, however, performed poorly resulting in significant deterioration in wear performance while the alumina filled G‐E composite showed improved abrasion resistance. Selected mechanical properties such as hardness, tensile strength, and elongation at fracture were analyzed for investigating wear property correlations. The SEM studies indicate the reasons for failure of composites and influencing parameters. POLYM. COMPOS., 2009. © 2008 Society of Plastics Engineers
Tapioca starch‐poly(lactic acid)‐Cloisite 30B nanocomposite foams
Authors: Lee Siew Yoong , Hanna Milford A. 
Published: November 2008

AbstractTapioca starch (TS), poly(lactic acid) (PLA), and Cloisite 30B nanocomposite foams, with four clay contents of 1, 3, 5, 7 wt%, were prepared by a melt‐intercalation method. Selected structural, thermal, physical, and mechanical properties were characterized using X‐ray diffraction, scanning electron microscopy, differential scanning calorimetry, thermogravimetry analyses, and an Instron universal testing machine, respectively. XRD results indicated that intercalation of TS/PLA into the nanoclay layers occurred in all four nanocomposite foams. At the same time, tactoid structures were observed in all nanocomposite foams but to a lesser extend with 1 and 3 wt% clay contents. Effect of clay content on melting temperature (Tm), onset degradation temperature, radial expansion ratio, unit density, bulk compressibility and bulk spring index of the nanocomposites were investigated. Among the four nanocomposites, 3 wt% clay content produced significantly different (p < 0.05) properties. POLYM. COMPOS., 2009. © 2008 Society of Plastics Engineers
Modification of carbon nanotubes and its effect on properties of carbon nanotube/epoxy nanocomposites
Authors: Špitalský Zdenko , Matějka Libor , Šlouf Miroslav , Konyushenko Elena N. , Kovářová Jana , Zemek Josef , Kotek Jiří 
Published: November 2008

AbstractWe have studied an effect of three types of modifications of carbon nanotubes (CNTs) on dispersion and mechanical properties of final epoxy‐amine based nanocomposites. First approach includes end‐walled covalent chemical modification at the ends of nanotubes. The second one is side‐walled covalent chemical modification along the whole length of nanotubes. The third procedure is noncovalent, physical modification done by the CNT surface coating with polyaniline. The modification of nanotubes was determined by X‐ray photoelectron spectroscopy. The prepared epoxy‐amine nanocomposites were characterized by dynamic‐mechanical analysis, tensile testing, light microscopy, transmission electron microscopy, and thermogravimetry. We observed an improvement of the mechanical properties and the thermal stability by addition of the carbon nanotubes to the epoxy matrix. The strong interactions between the nanotube and the polymer matrix were discovered in the nanocomposites with physically modified nanotubes. POLYM. COMPOS., 2009. © 2008 Society of Plastics Engineers
Preparation and characterization of high permittivity and low loss PTFE/CaTiO3 microwave laminates
Authors: Rajesh S. , Murali K.P. , Ratheesh R. 
Published: November 2008

AbstractThis article discusses the preparation and characterization of CaTiO3 filled PTFE flexible laminates for microwave substrate applications. Single phase CaTiO3 filler composition was prepared through solid‐state ceramic route. Phase formation was confirmed by powder X‐ray diffraction studies. Morphology and filler distribution of the composites were studied using scanning electron microscopic technique. Permittivity and loss tangent of the composite substrates were measured at X‐band frequency region (8.2–12.4 GHz) using waveguide cavity perturbation technique. Effective permittivity of the composites was compared with theoretically predicted values. Temperature coefficient of permittivity (τεr) of the composites was also measured in the 0–100°C temperature range. PTFE/CaTiO3 composite has an effective permittivity of 11.8 and a loss tangent of 0.0036 at optimum filler loading. POLYM. COMPOS., 2009. © 2008 Society of Plastics Engineers
Nonlinear optical properties of poly‐ortho‐toluidine films implantated by N+ ions with different energy
Authors: Shaolin Yan , Hongcai Wu , Song Gao 
Published: November 2008

AbstractThis article reports experimental work on the effect of N+ ion implantation on third‐order nonlinear optical properties of POT films. Using K2Cr2O7 as oxidizing agent, poly‐ortho‐toluidine (POT) was synthesized in 1 M hydrochloric. The POT films were prepared by spin‐coating method and then implantated by N+ ions (15–30 KeV) at a dose 1.9 × 1016 ions/cm2. The films were characterized by FT‐IR spectroscopy, visible spectroscopy and SEM, their third‐order nonlinear optical susceptibility (χ(3)) were also examined by a degenerate four‐wave mixing (DFWM) system at 532nm. Compared to pristine POT films, the optical band gap obtained from visible spectra decreased from 3.58 to 3.48 eV when the energy was 30 KeV. Also, The χ(3) value of implantated POT films increased from 3.31 × 10−10 esu to 4.04 × 10−9 esu when the implantated energy was 25 KeV. POLYM. COMPOS., 2009. © 2008 Society of Plastics Engineers
Preparation and characterization of sepiolite‐poly(ethyl methacrylate) and poly(2‐hydroxyethyl methacrylate) nanocomposites
Authors: Benlikaya Ruhan , Alkan Mahir , Kaya İsmet 
Published: November 2008

AbstractPoly(ethyl methacrylate) (PEMA) and poly(2‐hydroxyethyl methacrylate) (PHEMA) nanocomposites with sepiolite in pristine and silylated form were prepared using the solution intercalation method and characterized by the measurements of XRD, TEM, FTIR‐ATR, TG/DTG, and DSC. The TEM analysis indicated that the volume fraction of fibers in sepiolite decreased and the fiber bundles dispersed in PEMA and PHEMA at a nanometer scale. These results regarding TEM micrographs were in agreement with the data obtained by XRD. The increase in thermal stability of nanocomposites of PEMA is higher than that of PHEMA according to the data obtained from TG curves. The DTG analysis revealed that sepiolite/modified sepiolite caused some changes, as confirmed by FTIR in the thermal degradation mechanism of the polymers. Tg temperatures of PEMA and PHEMA usually increased upon the addition of sepiolite/modified sepiolite. In addition, modification of sepiolite with 3‐APTS had a slight influence on thermal properties of the nanocomposites. POLYM. COMPOS., 2009. © 2008 Society of Plastics Engineers
Viscoplastic analysis of fiber reinforced polymer matrix composites under various loading conditions
Authors: Guedes R.M. 
Published: November 2008

AbstractThe present study aims modeling the viscoplastic behavior of polymer matrix composite laminates under different loading conditions. The adopted model is based on the one‐parameter plasticity model employed to predict the plastic part of the recognized nonlinear behavior of fiber composites [C.T. Sun and J.L. Chen, J. Compos. Mater., 23, 1009 (1989)]. This model evolved to a three‐parameter constitutive viscoplastic model used to describe successfully the strain‐rate dependent mechanical behavior. Based on this model, designated as 3PV, a numerical implementation was made, based on the Classical Laminate Theory (CTL), to simulate non‐linear behavior of general laminates. The validation of this numerical implementation was performed using experimental data reported in literature. The first step was to assess the model predictions under high strain rates. The model was able to model high strain rate mechanical response, of an epoxy system reinforced with glass fibers, between 10 and 2,500 s−1. Furthermore the model proved to be reasonable accurate to simulate creep, stress relaxation and constant strain rate loading of the same material system under high temperatures. Following the experimental observations of vsicoplasticity strain evaluation during load and unloading made by Kim and Tsai [J. Compos. Mater. 36(6), 745 (2002)], a simple model modification is suggested. This modified model proved accurate enough to simulate relaxation successfully of a composite during loading and unloading. POLYM. COMPOS., 2009. © 2008 Society of Plastics Engineers