bluuebunny/crossref_metadata_2025_split huggingface dataset:
Impact of corrections for dynamic selection bias on forecasts of retention behavior
Authors: Li Yang , Mayer Walter J. 
Published: December 2007

AbstractWe investigate the impact of corrections for dynamic selection bias on forecasting accuracy in a multi‐period stay/leave model. While corrections for selection bias are needed for consistent coefficient estimates, they do not necessarily produce more accurate forecasts than uncorrected techniques. Theorem 1 shows that, apart from estimation errors, a shrinkage principle applies: the heterogeneity restriction imposed by uncorrected and combination techniques improves accuracy for forecasting individuals that leave, and hurts accuracy for forecasting individuals that stay. This has important implications for decision making because of the potential for asymmetric losses. We also present an illustrative empirical application and results from Monte Carlo experiments. We find that differences in relative accuracy vary directly with the degree of selection bias and inversely with the percentage of the initial population that stays.  Copyright © 2007 John Wiley & Sons, Ltd.
Forecasting interest rate swap spreads using domestic and international risk factors: evidence from linear and non‐linear models
Authors: Lekkos Ilias , Milas Costas , Panagiotidis Theodore 
Published: December 2007

AbstractThis paper explores the ability of factor models to predict the dynamics of US and UK interest rate swap spreads within a linear and a non‐linear framework. We reject linearity for the US and UK swap spreads in favour of a regime‐switching smooth transition vector autoregressive (STVAR) model, where the switching between regimes is controlled by the slope of the US term structure of interest rates. We compare the ability of the STVAR model to predict swap spreads with that of a non‐linear nearest‐neighbours model as well as that of linear AR and VAR models. We find some evidence that the non‐linear models predict better than the linear ones. At short horizons, the nearest‐neighbours (NN) model predicts better than the STVAR model US swap spreads in periods of increasing risk conditions and UK swap spreads in periods of decreasing risk conditions. At long horizons, the STVAR model increases its forecasting ability over the linear models, whereas the NN model does not outperform the rest of the models.  Copyright © 2007 John Wiley & Sons, Ltd.
Alcohol intake and risk of breast cancer defined by estrogen and progesterone receptor status—A meta‐analysis of epidemiological studies
Authors: Suzuki Reiko , Orsini Nicola , Mignone Laura , Saji Shigehira , Wolk Alicja 
Published: December 2007

AbstractThe association between alcohol consumption and an increased risk of breast cancer has been established. It is still unclear however, whether this relationship differs across the estrogen receptor (ER) and progesterone receptor (PR) tumors subtypes. To provide a quantitative assessment of the association between alcohol intake and the risk of ER‐/PR‐defined breast cancer, we conducted a meta‐analysis of cohort and case–control studies. Studies were identified by a literature search of PubMed through April 20, 2007 and by searching the reference lists of relevant articles. Summarized risk estimates (REs) with 95% confidence intervals (CIs) were calculated using random‐effects models. The summarized results of the meta‐analysis comparing the highest versus the lowest consumption categories showed statistically significant higher risks of developing all ER+ (27%), all ER− (14%), ER+PR+ (22%) and ER+PR− (28%), but not ER−PR− tumors. The dose–response meta‐analysis showed that an increase in alcohol consumption of 10 g of ethanol per day was associated with statistically significant increased risks for all ER+ (12%), all ER− (7%), ER+PR+ (11%) and ER+PR− (15%), but not ER−PR−. A statistically significant heterogeneity of the REs across all ER+ versus ER−PR− was observed (pheterogeneity = 0.02). The summarized results from studies with adjustment for postmenopausal hormone use, body mass index and family history of breast cancer were higher and statistically significantly different from those without. The observed positive associations with alcohol for ER+PR+ and ER+PR− tumors cannot be explained by estrogen‐dependent pathway only. Further studies need to clarify the biological mechanisms. © 2007 Wiley‐Liss, Inc.
The influence of Sr doses on the in vitro biocompatibility and in vivo degradability of single‐phase Sr‐incorporated HAP cement
Authors: Dagang Guo , Kewei Xu , Yong Han 
Published: December 2007

AbstractIn previous studies, we developed a new type of Sr‐incorporated hydroxyapatite cement (Sr‐HAC), which was shown to have many excellent physiochemical properties, by an ionic cement route (Guo et al., Biomaterials 2005;26:4073‐4083). As a further study, the main aims of this article were to examine the Sr‐HAC's in vitro biocompatibility, including acute toxicity, hemolytic reaction, pyrogen reaction, and cytoxicity, to evaluate its in vivo degradability during intramuscular and femur implantation, and also to investigate the influence of Sr doses on these properties. The in vitro results show that all of the Sr‐HAC samples exhibit satisfactory biocompatibility, and the Sr/(Sr+Ca) molar ratio has an important effect on these properties. For example, the Sr‐HAC with a Sr/(Sr+Ca) molar ratio of 5% (5% Sr‐HAC) has higher biocompatibility than both the one with a Sr/(Sr+Ca) molar ratio of 10% (10% Sr‐HAC) and the Sr‐free one. The in vivo results of both the rabbit intramuscular and femur implantation experiments show that the Sr‐HAC samples exhibit a much faster degradation rate than the Sr‐free one, and that this also depends on the Sr/(Sr+Ca) molar ratio. Specifically, the mean degradation rate of the 10% Sr‐HAC increases by an amplitude of 73.9 wt % compared with that of the Sr‐free HAC. In addition, the optical transmission photographs show that the Sr doses play an important role on the interface between the implants and the new bone. The energy dispersion X‐ray spectrum analysis indicates that there exists a gradient distribution of Sr element in the tight and bioactive interface between the implants and new bone, indicating that the Sr element takes a share in the mineralization of the new bone together with Ca element. © 2007 Wiley Periodicals, Inc. J Biomed Mater Res 2008
Effect of surface chemistry modification of functional gold nanoparticles on the drug accumulation of cancer cells
Authors: Song Min , Wang Xuemei , Li Jingyuan , Zhang Renyun , Chen Baoan , Fu Degang 
Published: December 2007

AbstractIn this report, we have explored the possibility to facilitate the drug delivery efficiency for cancer cells through the surface chemistry modification of gold nanoparticles (AuNPs), where the functional AuNPs were synthesized by the ligand exchange reaction between triphenyl phosphide‐stabilized precursor nanoparticles and mercaptopropionic acid. Our observations demonstrate that the combination of the anticancer drug daunorubicin with relevant AuNPs could be used as an efficient way to mark the cancer cells, which may afford the potential application for the early diagnosis of the respective cancers. Besides, the synergistic enhanced effect of the relevant gold nanoparticles on the drug uptake of target cancer cells could provide a new strategy to inhibit the multidrug resistance of the respective cancers. © 2007 Wiley Periodicals, Inc. J Biomed Mater Res 86A: 942–946, 2008
Polymer cell culture substrates with micropatterned carbon nanotubes
Authors: Eliason Marcus T. , Sunden Erik O. , Cannon Andrew H. , Graham Samuel , García Andrés J. , King William P. 
Published: December 2007

AbstractThis article presents study of the interactions between cells and micropatterned carbon nanotubes on a polymer cell culture substrate. The polymer substrates with patterned carbon nanotubes were fabricated using an imprint process, whereby the nanotubes were pressed into a polymer layer at high temperature. The patterned substrates featured 28 different nanotube patterns of microscale lanes and circles, where the feature sizes ranged from 9 to 76 μm. Osteoblast‐like cells were seeded on the substrates and cell alignment was quantified via fluorescent and electron microscopy. Many patterns were fabricated on each polymer substrate, allowing 28 different experiments on each cell culture substrate, which were tested over 10,000 cells. The cell response to the patterned nanotubes showed a maximum alignment to the microlane patterns of 55 ± 6% and no significant alignment to microcircle patterns. This work enables the study of cell response to a wider range of patterns featuring both the micro and nano length scales. © 2007 Wiley Periodicals, Inc. J Biomed Mater Res 2008
Therapeutic doses of radiation alter proliferation and attachment of osteoblasts to implant surfaces
Authors: Ahmad Mansur , Sampair Christopher , Nazmul‐Hossain Abu N. M. , Khurana Neerja , Nerness Andrew , Wutticharoenmongkol Patcharaporn 
Published: December 2007

AbstractOsseointegration of implants in irradiated bone is inadequate. The effect of radiation on cell‐implant material interaction has not been adequately studied. The goal of this study was to investigate the effects of ionizing radiationon the proliferation, differentiation, and attachment of osteoblasts to commercially pure titanium (cpTi). Human fetal osteoblasts (hFOB) were irradiated either before or after plating in tissue culture (TC) dishes with or without cpTi disks. Radiation was single dose of 10 cGy, 25 cGy, 50 cGy, 1 Gy, 2 Gy, 4 Gy or 8 Gy. Cell proliferation was determined by counting trypsinized cells on 7 days after irradiation. Attachment of irradiated hFOB was measured indirectly by counting cells 2 and 6 h after plating. Differentiation was evaluated by alkaline phosphatase activity. Compared with nonirradiated sham controls, higher doses of radiation significantly reduced cell attachment and proliferation. Both proliferation and attachment were significantly lower on cpTi compared with TC. Attachment decreased based on the length of postirradiation period. Although differentiation was significantly enhanced by a dose of 8 Gy, proliferation was lowest. These initial studies show that effects of therapeutic doses of radiation on osteoblasts varied depending on the surface, time‐elapsed, and amount of radiation. © 2007 Wiley Periodicals, Inc. J Biomed Mater Res, 2008
Interaction of glycopolymers with human hematopoietic cells from cord blood and peripheral blood
Authors: Lee Yong‐Su , Park Keun‐Hong , Kim Tea‐Sik , Kim Jea‐Myeoung , Sohn In‐Sook , Park Jin‐Ki , Chang Won‐Kyong , Kim Dong‐Ku 
Published: December 2007

AbstractPolystyrene derivatives, poly[N‐pvinylbenzyl‐O‐D‐glucopyranosyl‐(1‐4)‐D‐glucoamide] (PV Maltose) and poly[N‐p‐vinylbenzyl‐O‐mannopyranosyl‐(1‐4)‐D‐glucoamide] (PV Mannose), which contain glucose and mannose moieties, respectively, have the specific binding ability with murine hematopoietic cells. In this study, we confirm the ability of these glycopolymers to interact specifically with human hematopoietic stem cells (HSCs) and mature cells derived from human cord blood (CB) and peripheral blood (PB). Using fluorescence isothiocyanate (FITC)‐labeled glycopolymers, we observed that 98% to 93% of hematopoietic cells interacted very strongly with PV Mannose, and 63% of CB and 29% PB interacted with PV Maltose. Both glycopolymers bound better to cells from CB than from PB. Cytotoxic studies revealed that a 0.1 mM dose of PV Mannose induced apoptosis in 20% CB cells, in contrast to 3–5% PB cells. Furthermore, we demonstrated that all of CD34+ HSCs of both origins bound specifically to PV Mannose, whereas 33–47% bound to PV Maltose. In addition, the majority of B cells (CD19+), T cells (CD3+), monocytes (CD14+), and erythrocytes (CD235a+) bound to PV Mannose, but a lower percentage interacted with PV Maltose. In vivo study, bone marrow, spleen, and liver tissues in NOD‐SCID mice injected with PV Mannose conjugated CB, were detected PV Mannose positive hematopoietic cells. These data suggest that the use of PV Mannose and PV Maltose might be used for gene and drug delivery for hematopoietic cells and thus, may be useful in therapeutic settings. © 2007 Wiley Periodicals, Inc. J Biomed Mater Res, 2008
Regeneration of dentin‐pulp complex with cementum and periodontal ligament formation using dental bud cells in gelatin‐chondroitin‐hyaluronan tri‐copolymer scaffold in swine
Authors: Kuo Tzong‐Fu , Huang An‐Ting , Chang Hao‐Hueng , Lin Feng‐Huei , Chen San‐Tai , Chen Rung‐Shu , Chou Cheng‐Hung , Lin Hsin‐Chi , Chiang Han , Chen Min‐Huey 
Published: December 2007

AbstractThe purpose of this study is to use a tissue engineering approach for tooth regeneration. The swine dental bud cells (DBCs) were isolated from the developing mandibular teeth, expanded in vitro, and cultured onto cylinder scaffold gelatin‐chrondroitin‐hyaluronan‐tri‐copolymer (GCHT). After culturing in vitro, the DBCs/GCHT scaffold was autografted back into the original alveolar socket. Hematoxylin and eosin (H&E) staining combined with immunohistochemical staining were applied for identification of regenerated tooth structure. After 36‐week post‐transplantation, tooth‐like structures, including well‐organized dentin‐pulp complex, cementum, and periodontal ligament, were evident in situ in two of six experimental animals. The size of the tooth structure (1 × 0.5 × 0.5 cm3 and 0.5 × 0.5 × 0.5 cm3 size) appeared to be dictated by the size of the GCHT scaffold (1 × 1 × 1.5 cm3). The third swine was demonstrated with irregular dentin‐bony like calcified tissue about 1 cm in diameter without organized tooth or periodontal ligament formation. The other three swine in the experimental group showed normal bone formation and no tooth regeneration in the transplantation sites. The successful rate of tooth regeneration from DBCs/GCHT scaffolds' was about 33.3%. In the control group, three swine's molar teeth buds were removed without DBCs/GCHT implantation, the other three swine received GCHT scaffold implants without DBCs. After evaluation, no regenerated tooth was found in the transplantation site of the control group. The current results using DBSs/GCHT scaffold autotransplantation suggest a technical breakthrough for tooth regeneration. © 2007 Wiley Periodicals, Inc. J Biomed Mater Res 2008
Three‐dimensional sonographic measurement of contralateral lung volume in fetuses with isolated congenital diaphragmatic hernia
Authors: Ruano Rodrigo , Aubry Marie‐Cécile , Barthe Bruno , Dumez Yves , Zugaib Marcelo , Benachi Alexandra 
Published: December 2007

AbstractPurposeTo use 3‐dimensional sonography (3DUS) to measure contralateral lung volume and evaluate the potential of this measurement to predict neonatal outcome in isolated congenital diaphragmatic hernia (CDH).MethodsBetween January 2002 and December 2004, the contralateral lung volumes of 39 fetuses with isolated CDH were measured via 3DUS using rotational multiplanar imaging. The observed/expected contralateral fetal lung volume ratios (o/e‐ContFLVR) were compared with the lung/head ratio (LHR), observed/expected total fetal lung volume ratio (o/e‐TotFLVR), and postnatal outcome.ResultsContralateral lung volumes are less reduced than total lung volumes in CDH. The bias and precision of 3DUS in estimating contralateral lung volumes were 0.99 cm3 and 1.11 cm3, respectively, with absolute limits of agreement ranging from −1.19 cm3 to +3.17 cm3. The o/e‐ContFLVR was significantly lower in neonatal death cases (median, 0.49 cm3; range, 0.22–0.99 cm3) than in survival cases (median, 0.58 cm3; range, 0.42–0.92 cm3 [p < 0.01]). Overall accuracy of the o/e‐ContFLVR, o/e‐TotFLVR, and LHR in predicting neonatal death were 67.7% (21/31), 80.7% (25/31), and 77.4% (24/31), respectively.ConclusionAlthough o/e‐ContFLVR can be precisely measured with 3DUS and can be used to predict neonatal death in CDH, it is less accurate than LHR and o/e‐TotFLVR for that purpose. © 2007 Wiley Periodicals, Inc. J Clin Ultrasound, 2008
Promoters influence the kinetics of transgene expression following adenovector gene delivery
Authors: Chen Ping , Tian Jie , Kovesdi Imre , Bruder Joseph T. 
Published: December 2007

AbstractBackgroundThe kinetics of gene expression from adenovirus‐based delivery vectors will be an important variable influencing the efficacy and toxicity of these vectors. As different promoters have variable strengths and kinetic profiles, the optimal dose of a therapeutic transgene product over time may be achieved by varying the promoter.MethodsWe analyzed several viral and cellular promoters in the context of adenovector gene delivery in the mouse. The kinetics of transgene expression was evaluated following intramuscular and intravenous delivery.ResultsTransgene expression from the cytomegalovirus (CMV) promoter was rapidly down‐regulated in the tissues following intravenous administration of adenovectors. In contrast, transgene expression from the Rous sarcoma virus (RSV) promoter increased over time such that, at 3 weeks, expression was 10‐fold higher than that from the CMV promoter‐containing vector in all tissues. The kinetics of transgene expression from these vectors was similar when they were delivered via the intramuscular route in BALB/c, C57BL/6 and immunodeficient mice. Efficient repeat administration of an adenovirus vector, in the presence of neutralizing antibodies, was achieved in the skeletal muscle and transgene expression persisted with the same kinetics as in naïve animals.ConclusionsThese results demonstrate that the in vivo kinetics of transgene expression by adenovectors is greatly influenced by the promoter. Adenovectors can be designed to deliver a transient bolus or a sustained level of protein expression in the target tissue depending on the requirements for particular indications. These results have implications for both therapeutic and vaccine indications. Copyright © 2007 John Wiley & Sons, Ltd.
Quantitative motor unit potential analysis in the diaphragm: A normative study
Authors: Podnar Simon , Resman‐Gašperšič Anita 
Published: December 2007

AbstractAlthough quantitative motor unit potential (MUP) analysis has an established role in other skeletal muscles, it has not been performed in the diaphragm. The aim of the present study was to test whether such studies are possible and to establish normative data. Twenty‐nine healthy volunteers (15 men), aged 21–65 years (median, 33 years), were studied using standard concentric needle electrodes, and equipment with the facility for template‐operated multi‐MUP analysis. Needle electrodes were inserted into the right medial recess of the seventh to ninth intercostal spaces. During MUP sampling, subjects were asked to hold their breath in partial inspiration for 5 s. At least 20 MUPs were obtained in 28 subjects. Diaphragmatic MUPs were confirmed to be much smaller than those of limb muscles. We found diaphragmatic quantitative MUP analysis to be possible in healthy volunteers. However, further studies in patient groups are needed to establish the feasibility and clinical value of such studies. Muscle Nerve, 2007
Preparation and cryogenic mechanical properties of epoxy resins modified by poly(ethersulfone)
Authors: Yang Guo , Zheng Bin , Yang Jiao‐Ping , Xu Guan‐Shui , Fu Shao‐Yun 
Published: December 2007

AbstractA thermoplastic, poly(ethersulfone) (PES) was used to modify a bisphenol‐F based epoxy resin cured with an aromatic diamine. The initial mixtures before curing, prepared by melt mixing, were homogeneous. Scanning electron microscopy (SEM) micrographs of solvent‐etched fracture surfaces of the cured blends indicated that phase separation occurred after curing. The cryogenic mechanical behaviors of the epoxy resins were studied in terms of tensile properties and Charpy impact strength at cryogenic temperature (77 K) and compared to their corresponding behaviors at room temperature (RT). The addition of PES generally improved the tensile strength, elongation at break, and impact strength at both RT and 77 K except the RT tensile strength at 25 phr PES content. It was interesting to observe that and the maximum values of the tensile strength, elongation at break, and impact strength occurred at 20 phr PES content where a co‐continuous phase formed. Young's modulus decreased slightly with the increase of the PES content. Moreover, the tensile strength and Young's modulus at 77 K were higher than those at RT at the same composition, whereas the elongation at break and impact strength showed the opposite results. Finally, the differential scanning calorimetry analysis showed that the glass transition temperature (Tg) was enhanced by the addition of PES. © 2007 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 46: 612–624, 2008
An incremental development of the Mondex system in Event-B
Authors: Butler Michael , Yadav Divakar 
Published: December 2007

Abstract
A development of the Mondex system was undertaken using Event-B and its associated proof tools. An incremental approach was used whereby the refinement between the abstract specification of the system and its detailed design was verified through a series of refinements. The consequence of this incremental approach was that we achieved a very high degree of automatic proof. The essential features of our development are outlined. We also present some modelling and proof guidelines that we found helped us gain a deep understanding of the system and achieve the high degree of automatic proof.
Surgical Thrombectomy for Thrombosed Dialysis Grafts: Comparison of Adjunctive Treatments
Authors: Ko Po‐Jen 
Published: December 2007

AbstractBackgroundVascular surgeons often encounter dialysis graft failure in hemodialysis patients during their daily practice. Despite advances in percutaneous treatment, there remains a role for surgical thrombectomy of thrombosed dialysis grafts. This study was designed to investigate the long‐term outcome of dialysis graft thrombectomy and to examine the indications for and effectiveness of therapies adjuvant to Fogarty thrombectomy.MethodsSurgical outcomes of 590 consecutive dialysis graft thrombectomies performed between 2001 and 2003 were retrospectively reviewed. The 590 cases were classified into four groups based on the procedure performed adjuvant to Fogarty thrombectomy: group A, surgical thrombectomy by Fogarty thrombectomy catheter alone; group B, thrombectomy plus intraoperative angioplasty of graft outlet; group C, thrombectomy plus sequential balloon angioplasty in subsequent intervention; group D, thrombectomy plus graft outlet surgical revision. Age, gender, co‐morbidity, and primary patency of grafts were reviewed and analyzed.ResultThe four groups exhibited similar demographic features and comorbidities (p > 0.05). Mean primary patency in the four groups was 1.99 ± 4.02, 7.21 ± 7.61, 8.35 ± 9.53, and 7.26 ± 6.99 (months), respectively. Survival curves for each group were determined by Kaplan‐Meier methods. Primary patency in group A was statistically inferior to all of the other three groups, whereas groups B, C, and D did not significantly differ with regard to graft patency.ConclusionsSurgical thrombectomy alone is inadequate for treating a thrombosed dialysis graft. The underlying graft outlet stricture requires direct surgical revision or balloon angioplasty during surgery or intervention in the angiography suite to ensure long‐term patency of the graft.