bluuebunny/crossref_metadata_2025_split huggingface dataset:
Numerical modeling of projectile penetration into compressible rigid viscoplastic media
Authors: Cazacu Oana , Ionescu Ioan R. , Perrot Thomas 
Published: October 2007

AbstractWe develop computational methods for modeling penetration of a rigid projectile into porous media. Compressible rigid viscoplastic models are used to capture the solid–fluid transition in behavior at high strain rates and account for damage/plasticity couplings and viscous effects that are observed in geological and cementitious materials.A hybrid time discretization is used to model the non‐stationary flow of the target material and the projectile–target interaction, i.e. an explicit Euler method for the projectile equation and a forward (implicit) method for the target boundary value problem. At each time step, a mixed finite element and finite‐volume strategy is
used to solve the ‘target’ boundary value problem. Specifically, the non‐linear variational inequality for the velocity field is discretized using the finite element method while a finite‐volume method is used for the hyperbolic mass conservation and damage evolution equations. To solve the velocity problem, a decomposition–coordination formulation coupled with the augmented Lagrangian method is adopted.Numerical simulations of penetration into concrete were performed. By conducting a time step sensitivity study, it was shown that the numerical model is robust and computationally inexpensive. For the constants involved in the model (shear and volumetric viscosities, cut‐off yield limit, and exponential weakening parameter for friction) that cannot be determined from data, a parametric study was performed. It is shown that using the material model and numerical algorithms that developed the evolution of the density changes around the penetration tunnel, the shape and location of the rigid/plastic boundary, the compaction zones, and the extent of damage due to air‐void collapse are described accurately. Copyright © 2007 John Wiley & Sons, Ltd.
Poly (3,4‐ethylenedioxythiophene) γ‐Fe2O3 polymer composite–super paramagnetic behavior and variable range hopping 1D conduction mechanism–synthesis and characterization
Authors: Singh Kuldeep , Ohlan Anil , Saini Parveen , Dhawan S. K. 
Published: October 2007

AbstractThe present paper reports the preparation of poly (3,4‐ethylenedioxythiophene) (PEDOT) ferrimagnetic conducting polymer composite by incorporation of ferrite particles in the polymer matrix by emulsion polymerization. Synthesis of PEDOT–γ‐Fe2O3 composite was carried out by chemical oxidative polymerization of EDOT with ferrite particles in the presence of dodecylbenzenesulfonic acid (DBSA) that works as dopant as well as surfactant in aqueous medium. The resulting conducting composite possesses saturation magnetization (Ms) value of 20.56 emu/g with a conductivity of 0.4 Scm−1, which was determined by VSM and four probe technique, respectively. B‐H curve reveals that ferrimagnetic particles of γ‐Fe2O3 show super‐paramagnetic behavior at room temperature which was also observed in PEDOT–γ‐Fe2O3 composite. The resulting conducting ferrimagnetic composite shows microwave absorption loss of 18.7–22.8 dB in the frequency range of 12.4–18 GHz. Thermogravimetric analysis of the composite revealed that the composite is thermally stable up to 230°C. The characterization of the PEDOT–γ‐Fe2O3 composite was carried out using XRD and FTIR spectroscopy. Copyright © 2007 John Wiley & Sons, Ltd.
Field‐induced bending deformation of various rubber films
Authors: Watanabe Masashi 
Published: October 2007

AbstractThe field‐induced bending deformation of various rubber films was measured. The deformation tended to increase with the increase in the conductivity of the films. In addition, the effect of doping with tetracyanoethylene (TCNE) was also studied. This doping significantly enhanced the bending deformation and conductivity when the film was made of acrylonitrile‐butadiene rubber. The tip of the film (5 × 30 mm2, 0.28 mm thick) moved by 3 mm due to the bending deformation induced by the applied voltage (140 V). Such a rubber film may find applications as a polymer actuator. Copyright © 2007 John Wiley & Sons, Ltd.
Synthesis and characterization of dual‐responsive micrometer‐sized core‐shell composite polymer particles
Authors: Alam M. Ashraful , Miah M. A. Jalil , Ahmad Hasan 
Published: October 2007

AbstractDual‐responsive micrometer‐sized core‐shell composite polymer particles were prepared by dispersion polymerization followed by seeded copolymerization. Polystyrene (PS) particles prepared by dispersion polymerization were used as core particles. N‐isopropyl acrylamide (NIPAM) and methacrylic acid (MAA) were used to induce dual‐responsive that is thermo‐ and pH‐responsive properties in the shell layer of composite polymer particles, prepared by seeded copolymerization with PS core particles. Temperature‐ and pH‐dependent adsorption behaviors of some macromolecules on composite polymer particles indicate that produced composite polymer particles exhibit dual‐responsive surface properties. Copyright © 2007 John Wiley & Sons, Ltd.
Porous 3‐D scaffolds from regenerated Antheraea pernyi silk fibroin
Authors: Li Mingzhong , Tao Wei , Lu Shenzhou , Zhao Chunxia 
Published: October 2007

AbstractIn this study, porous three‐dimensional (3‐D) materials were prepared with the regenerated Antheraea pernyi (A. pernyi) silk fibroin by freeze‐drying from a lithium thiocyanate solution of its fibers. The relationship between preparation conditions and morphological structures of 3‐D materials was also studied. We concluded that with the decrease in A. pernyi silk fibroin solution concentration and the increase in the freezing temperature, the porosity and the average pore diameter of the 3‐D materials were increased while the pore density was decreased. By adjusting the freezing temperature and the silk fibroin solution concentration, the 3‐D materials having the average pore diameter of 75–260 µm and the porosity of 70–90% can efficiently be produced. As a kind of new material with excellent biocompatibility and bioactivity, the material is expected to be applied to tissue regeneration scaffolds. Copyright © 2007 John Wiley & Sons, Ltd.
ΔNp63 isoforms regulate CD44 and keratins 4, 6, 14 and 19 in squamous cell carcinoma of head and neck
Authors: Boldrup L , Coates PJ , Gu X , Nylander K 
Published: October 2007

AbstractThe human p63 gene codes for multiple protein isoforms and is commonly over‐expressed in squamous cell carcinoma of head and neck (SCCHN). This expression is predominantly of the ΔN‐ and β‐isoforms, the former lacking the p53‐related transactivation domain. p63 can activate or repress transcription of p53 and p73 target genes, but also has unique transcriptional targets and, unlike other p53 family members, is required for normal development and differentiation of squamous epithelia. We have identified novel targets of p63, using microarray analysis of SCCHN cells that stably over‐express individual ΔNp63 isoforms. All three isoforms induced expression of the cancer stem cell marker, CD44, with the ΔNp63β isoform showing strongest induction. Using chromatin immunoprecipitation, we were unable to show direct binding of p63 to the CD44 promoter, but found that p63 specifically increased expression of CD44 lacking variant exon 2. Each of the ΔNp63 isoforms up‐regulated expression of keratins 6A and 14 and down‐regulated expression of keratins 4 and 19, in keeping with their expression patterns in SCCHN. The data strengthen the idea that p63 has key roles in regulating normal and abnormal differentiation processes through both induction and repression of genes with opposite functions. The identification of up‐regulation and differential splicing of CD44 following p63 over‐expression indicates roles in the regulation of adhesion, metastasis and the cancer stem cell phenotype. Copyright © 2007 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.
Selective loss of B‐cell phenotype in lymphocyte predominant Hodgkin lymphoma
Authors: Tedoldi S , Mottok A , Ying J , Paterson JC , Cui Y , Facchetti F , van Krieken JHJM , Ponzoni M , Özkal S , Masir N , Natkunam Y , Pileri SA , Hansmann M‐L , Mason DY , Tao Q , Marafioti T 
Published: October 2007

AbstractThe neoplastic Reed–Sternberg cells characteristic of classical Hodgkin's lymphoma (cHL) are of B‐cell origin but they almost always show striking loss of a range of B‐cell‐associated molecules. In contrast, the neoplastic cells found in lymphocyte predominant Hodgkin's lymphoma (LPHL) (L&H cells) are traditionally thought of as possessing the full repertoire of features associated with germinal centre B cells (eg BCL‐6 expression, ‘ongoing’ Ig gene mutation). In the present paper, we report an extensive phenotypic analysis of L&H cells which revealed down‐regulation of a number of markers associated with the B‐cell lineage (eg CD19, CD37) and with the germinal centre maturation stage (eg PAG, LCK). The promoter methylation status of three of these down‐regulated genes (CD10, CD19, and LCK) was further studied in microdissected L&H cells, and this revealed that their promoters were unmethylated. In contrast, these genes showed promoter methylation in cell lines derived from CHL. Further investigation of the mechanisms responsible for the deregulation of these molecules in L&H cells may provide new insights into the genetic abnormalities underlying LPHL. Copyright © 2007 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.
Stress and burnout in colorectal and vascular surgical consultants working in the UK National Health Service
Authors: Sharma A. , Sharp D. M. , Walker L. G. , Monson J. R. T. 
Published: October 2007

AbstractBackground: It has been suggested that dealing with cancer is associated with increased stress and burnout in health‐care professionals. The aim of this study is to examine the prevalence of psychiatric morbidity and burnout in surgeons working in the National Health Service (NHS), and the putative relationship between psychiatric morbidity, burnout and the amount of cancer‐related work.Methods: All consultant colorectal and vascular surgeons identified from their professional societies were sent a booklet consisting of questions about cancer‐related and specialty‐specific work load, job satisfaction and socio‐demographics. It also included the General Health Questionnaire (GHQ‐12), the Maslach Burnout Inventory (MBI) and the Coping Questionnaire.Logistic regression analysis was used to identify independent predictors of psychiatric morbidity (GHQ), burnout (MBI) and retirement intentions.Results: Five hundred and one questionnaire booklets were completed and returned (response rate 58.7%). The mean age of respondents was 47 years (range 31–65). The majority of the surgeons were male (460, 92%).One hundred and sixty‐three (33%) surgeons scored in the positive range of the GHQ, and 154 (32%) had high burnout on at least one subscale of the MBI. Three hundred and eighty‐three (77%) surgeons stated that they intended to retire before the statutory retirement age.Level of work satisfaction and perceived adequacy of training in communication and management skills were significantly negatively correlated with GHQ and MBI scores. Surgeons who planned to take early retirement or wished to retire as soon as they could afford to were more likely to have psychiatric morbidity and/or burnout. Surgeons who were married or cohabiting were less likely to have psychiatric morbidity, and younger surgeons were more likely to have higher levels of depersonalization (DP). Work satisfaction was negatively correlated with psychiatric morbidity and all three burnout scales.Colorectal surgeons had a greater cancer‐related workload than vascular surgeons (48.6 vs 7.5%, respectively, U=2667, p<0.005). However, there were no significant differences between the two groups in psychiatric morbidity, personal accomplishment and emotional exhaustion. Vascular surgeons, however, had significantly higher levels of DP (p=0.04).Conclusion: Levels of psychiatric morbidity, burnout and work dissatisfaction are worryingly high in colorectal and vascular surgeons and are likely to impact adversely on patient satisfaction and service quality. The number of surgeons intending to retire early is also a cause for concern both in terms of the overall number of trained surgeons in the NHS and in the balance between senior and junior surgeons. Apart from DP, these indicators of stress, however, were unrelated to cancer workload. Copyright © 2007 John Wiley & Sons, Ltd.
Psychosexual functioning of childhood cancer survivors
Authors: van Dijk E. M. , van Dulmen‐den Broeder E. , Kaspers G. J. L. , van Dam E. W. C. M. , Braam K. I. , Huisman J. 
Published: October 2007

AbstractPurpose: The objective of the study is to explore psychosexual functioning and its relationship with quality of life in survivors of cancer in childhood.Methods: Sixty childhood cancer survivors completed two questionnaires: psychosexual and social functioning questionnaire and MOS‐SF‐36.Results: Psychosexual problems were frequent. About 20% of the survivors felt a limitation in their sexual life due to their illness. Older survivors (⩾25 years) had significantly less experience with sexual intercourse than their age‐matched peers in the Dutch population (p = 0.010). Survivors treated in adolescence had a delay in achieving psychosexual milestones compared with those treated in childhood: dating (p<0.025), touching under clothes (p<0.025), masturbation (female) (p<0.05) and sexual intercourse (p<0.025). No differences were found for sexual fantasies, kissing, masturbation (male) and oral sex. The total survivor group appraised their quality of life as less positive than their Dutch peers for the subscales of general and mental health (both p<0.001), physical and social functioning (p<0.01; p<0.001), bodily pain and vitality (both p<0.001). However, quality of life was not more affected adversely in survivors with psychosexual problems compared with survivors without these problems.Conclusion: In this cohort of childhood cancer survivors, psychosexual problems were frequent. Treatment in adolescence is a risk factor for a delay in psychosexual development. Copyright © 2007 John Wiley & Sons, Ltd.
Supportive–expressive group therapy for primary breast cancer patients: a randomized prospective multicenter trial
Authors: Classen Catherine C. , Kraemer Helena C. , Blasey Christine , Giese‐Davis Janine , Koopman Cheryl , Palesh Oxana Gronskaya , Atkinson Ami , DiMiceli Sue , Stonisch‐Riggs Gail , Westendorp Joan , Morrow Gary R. , Spiegel David 
Published: October 2007

AbstractObjective: The aim is to evaluate the effectiveness of a manualized 12‐week supportive–expressive group therapy program among primary breast cancer patients treated in community settings, to determine whether highly distressed patients were most likely to benefit and whether therapist's training or experience was related to outcome.Method: Three hundred and fifty‐three women within one year of diagnosis with primary breast cancer were randomly assigned to receive supportive–expressive group therapy or to an education control condition. Participants were recruited from two academic centers and nine oncology practices, which were members of NCI's Community Clinical Oncology Program (CCOP) and were followed over 2 years.Results: A 2×2×19 analysis of variance was conducted with main effects of treatment condition, cohort, and baseline distress and their interactions. There was no main effect for treatment condition after removing one subject with an extreme score. Highly distressed women did not derive a greater benefit from treatment. Therapist training and psychotherapy experience were not associated with a treatment effect.Conclusions: This study provides no evidence of reduction in distress as the result of a brief supportive–expressive intervention for women with primary breast cancer. Future studies might productively focus on women with higher initial levels of distress. Copyright © 2007 John Wiley & Sons, Ltd.
Prostate cancer cells tolerate a narrow range of androgen receptor expression and activity
Authors: Tararova Natalia D. , Narizhneva Natalya , Krivokrisenko Vadim , Gudkov Andrei V. , Gurova Katerina V. 
Published: October 2007

AbstractBACKGROUNDThe precise role of androgen receptor (AR) in the normal development of prostate and the progression of prostate cancer (CaP) remains controversial. While AR expression and activity is associated with growth arrest and differentiation of normal prostate cells, it is maintained in CaP cells that are characterized by continued proliferation. Our objective was to determine the importance of AR signaling for survival and growth of CaP cells, particularly those with a hormone‐refractory phenotype.METHODAR expression was modulated in androgen‐sensitive (AS) and androgen‐insensitive (AI) CaP cells using RNAi and cDNA transduction. Resulting changes in AR transcriptional activity and cell growth were quantified.RESULTSInterference with AR expression in both AS and AI CaP cells by shRNA transduction demonstrated a direct correlation between residual AR expression and cell viability. CaP cells lacking AR expression undergo apoptosis several days after AR down‐regulation. This delayed response suggests that AR regulates apoptosis likely through an indirect mechanism. Overexpression of AR or hyper‐stimulation of AR with high levels of androgen was also poorly tolerated by CaP cells. Cells with elevated AR had a growth disadvantage due to G1 cell cycle arrest and induction of p21 and GADD45 expression.CONCLUSIONSCaP cells expressing endogenous AR are sensitive to both increases and decreases in AR expression levels and activity. AR in CaP cells is delicately regulated to provide a balance between cell death and continued proliferation. Thus, both approaches, inhibition and over‐stimulation of AR activity, may have therapeutic value for treatment of prostate cancer. Prostate 67: 1801–1815, 2007. © 2007 Wiley‐Liss, Inc.
Establishing normal reference ranges for prostate volume change with age in the population‐based Krimpen‐study: Prediction of future prostate volume in individual men
Authors: Bosch J.L.H.R. , Tilling K. , Bohnen A.M. , Bangma C.H. , Donovan J.L. 
Published: October 2007

AbstractBACKGROUNDWe aim to establish the normal pattern of prostate volume change with age to provide a baseline from which accelerated prostate growth might be identified in patients with lower urinary tract symptoms/benign prostatic hyperplasia (LUTS/BPH).METHODSIn a community‐based study, prostate volume was determined at baseline and after 2.1 and 4.2 years in men without prostate cancer. A bivariate multilevel growth curve model was used to estimate the pattern of change of prostate volume with age.RESULTSThe average percentage increase of total prostate volume and transition zone volume per year of follow‐up was 2.2% and 3.5%, respectively. The final model showed that prostate volume was related to age only. The future prostate volume of an individual can be predicted based on his age and known history of prostate volume. The model was also used to calculate time needed for the prostate volume to increase with a certain percentage, for men with different baseline prostate volume values at different ages.CONCLUSIONSThis method establishes normal prostate volume values by age using prostate volume history in men without prostate cancer. The model provides baseline data from which disease progression might be detected. Prostate 67: 1816–1824, 2007. © 2007 Wiley‐Liss, Inc.
Insecticidal activity of destruxin, a mycotoxin from Metarhizium anisopliae (Hypocreales), against Spodoptera litura (Lepidoptera: Noctuidae) larval stages
Authors: Sowjanya Sree K , Padmaja Vadlamani , Murthy Yellajyohula LN 
Published: October 2007

AbstractBACKGROUND: The cyclodepsipeptide destruxin produced by the entomopathogen Metarhizium anisopliae (Metch.) was administered by different methods, topical application, ingestion and a combination of the two, in an attempt to minimize the mycotoxin dose for efficient management of the insect pest Spodoptera litura (Fab.).RESULTS: The insecticidal activity of destruxin on the larval stages of S. litura showed an ascending trend in LD50 values with increasing age. The value for 12‐day‐old larvae in the combined application assay was as low as 0.045 µg g−1 body weight of crude destruxin from M‐19 strain when compared with the corresponding values of 0.17 µg g−1 body weight in the ingestion assay and 0.237 µg g−1 body weight in the topical application assay. On the other hand, values were higher in the treatments with crude destruxin from the low‐virulence M‐10 strain of M. anisopliae showing the least quantities of A and E components of destruxin.CONCLUSION: Laboratory bioevaluation showed the combination assay of ingestion and topical application of crude destruxin to be efficient in enhancing its insecticidal properties. The adopted combination assay apparently simulates application of the insecticide at field level. Quantitative differences between destruxins from low‐ and high‐virulence strains of M. anisopliae are in accordance with its presumed role in virulence. Copyright © 2007 Society of Chemical Industry
Population inversion of photoexcited electrons and holes in graphene and its negative terahertz conductivity
Authors: Ryzhii Victor , Ryzhii Maxim , Otsuji Taiichi 
Published: October 2007

AbstractWe demonstrate that sufficiently strong optical excitation may result in the population inversion in graphene, so that the real part of the ac conductivity can be negative in the terahertz range of frequencies. We study also how the heating of the electron‐hole system influences the effect of negative ac conductivity. The effect of population inversion and negative ac conductivity might be used in graphene‐based coherent sources of terahertz electromagnetic radiation. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Monte Carlo simulation of surface charge effects in T‐branch nanojunctions
Authors: González T. , Iñiguez‐de‐la‐Torre I. , Pardo D. , Mateos J. , Bollaert S. , Roelens Y. , Cappy A. 
Published: October 2007

AbstractWe analyze the influence of the surface charge on the operation of ballistic T‐branch junctions based on InAlAs/InGaAs layers by means of a semi‐classical 2‐D Monte Carlo simulator. A new self‐consistent model in which the local value of the surface charge is dynamically adjusted depending on the surrounding carrier density is used in the calculations. The rectifying behaviour exhibited by these devices (down‐bending shape of the output voltage VC as a function of the applied voltage VR = ‐VL =V) is found to be much influenced by the surface charge. A satisfactory agreement is achieved between simulated results and experimental measurements. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Transport properties of multi‐walled carbon nanotubes grown by boron addition method
Authors: Ishii S. , Okutsu T. , Ueda S. , Takano Y. 
Published: October 2007

AbstractThe transport property of boron‐doped multi‐walled carbon nanotubes (MWNTs) was investigated. The boron‐doped MWNTs were grown by a novel CVD process using a methanol solution of boric acid as a source material. In order to evaluate the transport property accurately, the electrical conductivity of each individual MWNT was measured by a four‐point method. Nano‐sized four electrodes with a width of several hundred nanometers were fabricated on an individual MWNT using electron beam (EB) lithography. The conductivity of a boron‐doped MWNT was one or two orders of magnitude higher than that of a non‐doped MWNT at room temperature. Furthermore, the boron‐doped MWNT was found to maintain a high conductivity at a very low temperature of 0.6 K, while the non‐doped MWNT became an insulator. The electrical conductivity of the MWNTs was increased by boron doping. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)