bluuebunny/crossref_metadata_2025_split huggingface dataset:
Fluid dynamic gauging: a new technique for studying membrane fouling
Authors: Chew Y.M.J. , Paterson W.R. , Wilson D.I. 
Published: December 2007

The deposition of fouling layers on porous surfaces such as those experienced in membrane/filtration systems has been investigated using the technique of fluid dynamic gauging (FDG). In this work, dead end microfiltration was simulated using polymeric microfiltration membranes and Sphericel (hollow glass spheres) suspensions. FDG was used to track, in situ and in real time, the build-up of a Sphericel cake during the filtration process. The permeate flux through the membrane was also simultaneously monitored.
Computational fluid dynamics (CFD) studies were also performed to illuminate the fluid dynamics of FDG, with particular focus on the flow patterns and on the stresses imposed on the porous surface. The governing Navier-Stokes, Darcy's and continuity equations were solved using the commercial partial differential equation solver, Fastflo™. Simulations of gauging flow with a permeable gauged surface were then conducted and comparison with filtration experiments showed excellent agreement.
Variation in hypothalamic–pituitary–adrenal axis activity among bullied and non‐bullied children
Authors: Vaillancourt Tracy , Duku Eric , Decatanzaro Denys , Macmillan Harriet , Muir Cameron , Schmidt Louis A. 
Published: December 2007

AbstractWe examined the relationship between being bullied during childhood and activity of the hypothalamic–pituitary–adrenal (HPA) axis as assessed through repeated measures of salivary cortisol. A non‐clinical sample of 154 (74 boys) predominantly Caucasian middle‐class 12‐year‐olds each provided detailed information about their experiences with bullying and six saliva samples were standardized across time and day. Children with a history of child maltreatment, diagnosed psychiatric illness, foster care placement, medication use (psychotropic and oral contraception) and aggression directed toward peers and/or family members were excluded. Using multilevel regression and applying orthogonal polynomial contrasts to model the observed circadian pattern in the data, we found that occasional and frequent verbal peer victimization was associated with hyposecretion of cortisol when controlling for sex, pubertal status, age, depression and anxiety. This relation, however, was moderated by sex. For boys, occasional exposure was associated with higher cortisol levels, whereas for girls exposure was associated with lower cortisol levels. The present study highlights the need to consider the plight of peer‐victimized children seriously, as it is associated with alterations to the HPA axis that affect males and females differently, and likely diminishes a person's ability to cope with stress, possibly placing them at risk for psychopathology and ill health. Aggr. Behav. 34:294–305, 2008. © 2007 Wiley‐Liss, Inc.
WT1 protein expression in childhood acute leukemia
Authors: Kerst Gunter , Bergold Nina , Gieseke Friederike , Coustan‐Smith Elaine , Lang Peter , Kalinova Marketa , Handgretinger Rupert , Trka Jan , Müller Ingo 
Published: December 2007

AbstractIn patients with acute leukemia, Wilms' tumor gene 1 (WT1) has been used as a target for the detection of minimal residual disease (MRD) by PCR techniques. The expression of WT1 protein, however, has not been extensively studied. To determine the relation between expression of WT1 transcripts and of the encoded protein, we examined leukemic cell lines and primary childhood leukemia samples using both real‐time quantitative PCR (RQ‐PCR) and flow cytometry. WT1 protein was highly expressed in the leukemic cell lines K562, HL‐60, PLB 985, KG‐1a and CEM. By contrast, 40 primary samples of acute lymphoblastic leukemia (ALL; B‐ALL, n = 15 and T‐ALL, n = 10) and acute myeloid leukemia (n = 15) expressed low levels of WT1 protein. RQ‐PCR detected WT1 transcript levels in the same range as reported in earlier studies in childhood acute leukemia. The results of this study indicate the following: (i) there are considerable discrepancies between WT1 transcripts and protein expression; (ii) WT1 is not a suitable marker for flow cytometric MRD detection in childhood acute leukemia. Am. J. Hematol., 2008. © 2007 Wiley‐Liss, Inc.
Development and validation of SIMS: An instrument for measuring quality of life of adults with sickle cell disease
Authors: Adams‐Graves Patricia , Lamar Kimberly , Johnson Cage , Corley Pat 
Published: December 2007

AbstractIn recent years, there has been a growing interest in the assessment of quality of life (QOL) issues, particularly in chronic debilitating conditions. Several instruments have been developed, tested, and validated in the general population and in other chronic diseases; however, few studies have examined QOL issues in adults with sickle cell disease (SCD). We developed Sickle Cell Impact Measurement Scale (SIMS), an instrument for measuring the QOL of adults with SCD. The 142‐item multi‐dimensional SIMS questionnaire was developed using 4 validated instruments and additional questions based upon recommendations of patient focus groups. The SIMS was self‐administered to 106 SCD and 45 rheumatoid arthritis (RA) patients over 4 sites. SIMS was evaluated on measures of both internal consistency and construct validity. Item reduction was performed based on results of factor analysis. The SIMS achieved good internal consistency, with a Cronbach's alpha coefficient reported of 0.86, and distinguished between patients with SCD and RA. Overall, QOL did not differ significantly among SCD and RA patients. However, SCD patients scored higher in both physical and social domains, which was expected and reflected the differences in the pathophysiology of each disease. The SIMS is a reliable, valid, and responsive questionnaire, which functions well as a discriminative instrument for the measure of health‐related QOL (HRQOL) of adults with SCD. The SIMS is currently being administered to adults with SCD across several centers for further validation to become a disease‐specific, global QOL instrument. Am. J. Hematol., 2008. © 2007 Wiley‐Liss, Inc.
Increased longevity in offspring of mothers with alzheimer's disease
Authors: Silverman Jeremy M. , Schmeidler James , Schnaider‐Beeri Michal , Grossman Hillel T. , Luo Xiaodong , West Rebecca , Lally Rachel C. , Wang Joy Y. 
Published: December 2007

AbstractLife expectancy is a familial trait. However, the effectiveness of using the age at death of a deceased parent to estimate life expectancy in their offspring can vary depending on whether death in the parent was due to extrinsic versus intrinsic causes, as well as demographic characteristics such as sex. While Alzheimer's disease (AD) risk increases with increased age, mortality for individuals with AD is increased in contrast to comparably aged individuals without AD. Yet in most cases it is not the defining neuropathology of AD that directly terminates life but instead conditions and illnesses extrinsic to AD pathology that nevertheless have increased likelihood in its presence. For this reason, we hypothesized that offspring of AD mothers would have greater longevity than offspring of mothers without AD (insufficient numbers prevented a comparable analysis using fathers with AD). The longevity of 345 offspring of 100 deceased 60+ year old AD mothers was compared with 5,465 offspring in 1,312 deceased 60+ year old non‐AD mothers. We used a proportional hazards model that accounted for clustered (nonindependent) observations due to the inclusion of several offspring from the same family. In both an unadjusted model and one that adjusted for the age at death in the mother, and the sex and birth year in the offspring we found evidence for increased longevity in the offspring of AD mothers. The results suggest that, in addition to genes that might directly affect pathways leading to AD, there may be familial/genetic factors not connected to specific pathophysiological processes in AD but instead associated with increased longevity that contribute to the familial aggregation observed in AD. © 2007 Wiley‐Liss, Inc.
Arboreal nesting as anti‐predator adaptation by savanna chimpanzees (Pan troglodytes verus) in southeastern Senegal
Authors: Pruetz J.D. , Fulton S.J. , Marchant L.F. , McGrew W.C. , Schiel M. , Waller M. 
Published: December 2007

AbstractChimpanzees (Pan troglodytes) make nests for resting and sleeping, which is unusual for anthropoid primates but common to all great apes. Arboreal nesting has been linked to predation pressure, but few studies have tested the adaptive nature of this behavior. We collected data at two chimpanzee study sites in southeastern Senegal that differed in predator presence to test the hypothesis that elevated sleeping platforms are adaptations for predator defense. At Assirik in the Parc National du Niokolo‐Koba, chimpanzees face four species of large carnivore, whereas at Fongoli, outside national park boundaries, humans have exterminated almost all natural predators. We quantified the availability of vegetation at the two sites to test the alternative hypothesis that differences in nesting reflect differences in habitat structure. We also examined possible sex differences in nesting behavior, community demographic differences, seasonality and nest age differences as variables also potentially affecting nest characteristics and nesting behavior between the two sites. Chimpanzees at Fongoli nested at lower heights and farther apart than did chimpanzees at Assirik and sometimes made nests on the ground. The absence of predators outside of the national park may account for the differences in nest characteristics at the two sites, given the similarities in habitat structure between Fongoli and Assirik. However, Fongoli chimpanzees regularly build arboreal nests for sleeping, even under minimal predation pressure, and this requires explanation. Am. J. Primatol. 70:393–401, 2008. © 2007 Wiley‐Liss, Inc.
A fine line: A comparison of methods for estimating ages of linear enamel hypoplasia formation
Authors: Ritzman Terrence B. , Baker Brenda J. , Schwartz Gary T. 
Published: December 2007

AbstractIt is accepted that linear enamel hypoplasias (LEHs), a specific type of enamel thickness deficiency, are related to periodic physiological disruptions to enamel matrix secretion during times that teeth are developing. Thus, LEHs are treated as general indicators of metabolic stress. Because the disruptions that cause LEHs affect only the portion of the crown that is in the process of forming, determining their locations allows researchers to reconstruct chronologies of stressful events. It is widely held that the many of the commonly used macroscopic methods for estimating the timing of LEHs are imprecise and do not conform to our current understanding of the process of enamel formation. The goal of the present study is to compare estimated ages of LEH formation produced by two of the most commonly used macroscopic methods to those derived from data in recent histological studies that include more precise information about the timing of crown formation across diverse human populations. These approaches are compared in two ways: 1) by creating a theoretical model using simulated LEHs and 2) empirically, by analyzing data collected on a sample of ancient Nubians from Semna South (present‐day Sudan). Results indicate that the approach derived from histological studies provides significantly higher age estimates than the commonly used methods and this difference is particularly marked in early forming LEHs. The magnitude of this difference is large enough to produce divergent interpretation of bioarchaeological datasets and suggests that reevaluation of the methods used to estimate ages of LEH formation may be justified. Am J Phys Anthropol, 2008. © 2007 Wiley‐Liss, Inc.
Population continuity or replacement? A novel computer simulation approach and its application to the numic expansion (Western Great Basin, USA)
Authors: Cabana Graciela S. , Hunley Keith , Kaestle Frederika A. 
Published: December 2007

AbstractIn a previous study, Kaestle and Smith [Am J Phys Anthropol 115 (2001) 1–12] supported a recent (A.D. 1000) Numic expansion into the Great Basin region based on a molecular and statistical analysis of mitochondrial DNA (mtDNA) of ancient and modern native inhabitants of the region. Their statistical methodology could not rule out the possibility that observed differences in haplogroup frequencies are instead the result of long‐term microevolutionary change within a single population. To distinguish more effectively between a Numic expansion versus population continuity, we employed a novel computer simulation approach that incorporates microevolutionary factors likely to affect human population genetic variation. We test whether the observed differences in haplogroup frequencies between ancient and modern Great Basin groups could have been produced solely via in situ microevolutionary change. Our results indicate that for reasonable demographic conditions, the observed genetic differences between the observed samples are consistent with population continuity if gene flow among prehistoric Great Basin local groups was less than 1% of local group size per generation. Our analysis also supports a recent population expansion if gene flow between neighboring groups exceeded 8% of local group size per generation. The simulations demonstrate that relatively low gene flow levels and random genetic drift can produce the observed degree of genetic differences between population samples. Although this study focuses on the Numic expansion, this simulation approach can be applied to any geographic region for which genetic data have been collected to address similar questions of population relationships over time. Am J Phys Anthropol, 2008. © 2007 Wiley‐Liss, Inc.
N‐alkylation of chitosan by β‐halopropionic acids in the presence of various acceptors
Authors: Pestov Alexander V. , Skorik Yury A. , Kogan Grigorij , Yatluk Yury G. 
Published: December 2007

AbstractN‐carboxyethylation of chitosan by β‐halopropionic acids in the presence of various proton and halogen ion acceptors was investigated. It has been observed that carboxyethylation of chitosan in aqueous medium is accompanied by the by‐processes of hydrolysis and dehydrohalogenation of the β‐halopropionic acids yielding β‐hydroxypropionic acid, bis(2‐carboxyethyl) ether, and acrylic acid. Degree of carboxyethyl substitution (DS) of chitosan and the relative rates of the by‐processes varied significantly depending on the conditions used and nature of the proton or halogen ion acceptor. At carboxyethylation of chitosan with the alkaline β‐bromopropionates, the DS increased in the order Cs+ < Rb+ < K+ ∼ Na+ < Li+. For alkaline earth salts BrCH2CH2COOM0.5 (M = Be2+, Mg2+, Ca2+, Sr2+, Ba2+), the highest DS was obtained with strontium and barium salts, which could be subsequently removed from the reaction mixture by precipitation as sulfates. Among the organic bases applied (tetrabutylammonium hydroxide, triethylamine, trimethylamine, pyridine, 4‐N,N‐dimethylaminopyridine, 2,6‐lutidine, and 1,5‐diazabicyclo[4.3.0] non‐5‐ene), the highest DS was obtained using a moderately strong base triethylamine. For the halogen acceptors (Pb2+, Ag+, Tl+), the stoichiometrically highest DS was achieved in a system comprising iodopropionic acid plus Tl+ and a comparable conversion rate was obtained using also a combination of chloropropionic acid and Ag+. A novel alternative preparative approach—gel‐state synthesis—was suggested that provides for the highest DS at the optimum reaction conditions. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2008
Synthesis of a cellulose‐grafted polymeric support and its application in the reductions of some carbonyl compounds
Authors: Dhiman Poonam K. , Kaur Inderjeet , Mahajan R. K. 
Published: December 2007

AbstractThe reduction of carbonyl compounds by borohydride supported on a cellulose–anion exchange resin is known. The synthesis of a graft copolymer of cellulose and poly(4‐vinyl pyridine) [CellO‐g‐poly(4‐VP)] has been carried out with ceric ions as a redox initiator. A postgrafting treatment of CellO‐g‐poly(4‐VP) with sodium borohydride has produced CellO‐g‐poly(4‐VP) borane, a polymer‐supported reducing agent. Optimum conditions pertaining to the maximum percentage of grafting have been evaluated as a function of the concentrations of the initiator, monomer, and nitric acid, amount of water, time, and temperature. The maximum percentage of grafting (585%) has been obtained with 0.927 mol/L of 4‐vinyl pyridine and 0.018 mol/L of ceric ammonium nitrate in 120 min at 45°C. The polymeric support, CellO‐g‐poly(4‐VP) borane, has been used for reduction reactions of different carbonyl compounds such as benzaldehyde, cyclohexanone, crotonaldehyde, acetone, and furfural. The graft copolymer has been characterized with IR and thermogravimetric analysis. The grafted cellulose has been found to be thermally stable. The reduced products have been characterized with IR and NMR spectral methods. The reagent has been reused for the reduction of a fresh carbonyl compound, and it has been observed that the polymeric reagent reduces the compounds successfully but with a little lower product yield. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2008
Phosphorus‐containing terephthaldialdehyde adducts—Structure determination and their application as flame retardants in epoxy resins
Authors: Seibold S. , Schäfer A. , Lohstroh W. , Walter O. , Döring M. 
Published: December 2007

AbstractTwo novel phosphorus‐rich prepolymers based on epoxy novolac and terephthaldialdehyde and potential flame retardants, 9,10‐dihydro‐9‐oxa‐10‐phosphaphenanthrene‐10‐oxide (DOPO) and 2,8‐dimethyl‐phenoxaphosphin‐10‐oxide (DPPO) were synthesised. The resultant flame‐retardant epoxy resins were cured with 4,4′‐diaminodiphenylmethane (DDM) and 4,4′‐diamino‐dicyclohexylmethane (PACM). Their flammability and burning behavior were characterised by UL 94 and LOI and compared with analogue prepolymers based on diethylphosphite (DEPP). The glass transition temperatures were determined by DSC measurements. Furthermore, the structures of two exemplary molecules based on p‐tolylaldehyde adducts were examined by XRD and NMR analysis to determine the possibilities of linking the two novel DOPO and DPPO derivatives to the backbone of the epoxy resin. Additionally, the char yields were determined by TG analysis and thermal desorption mass spectroscopy of the thermosets used and compared with each other to obtain more information about the possible mode of flame‐retardant action of the different phosphorus compounds. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2008
Gas turbine environment effect on morphology and mechanical properties of pultruded composite
Authors: Shivakumar Kunigal , Chen Huanchun , Holloway Gary 
Published: December 2007

AbstractThe effect of gas turbine lubricant oil soaking, thermal cycling and their combination on morphology and tension and flexure properties of pultruded composite was studied. Two types of lubricant oils were used: Mil‐L‐7808 and Mil‐L‐23699. Composite samples were oil soaked for 720 h and microscopic analysis and mechanical tests were conducted. Samples were thermal cycled for 600 cycles (RT to 315°C) and measured tension and flexure properties. Samples were oil soaked, thermal cycled and then tested. Results of these three groups of environmentally aged samples were compared with non‐aged samples. The significance of aging effect is discussed in the article. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2008
Double‐yielding behavior in injection‐molded polycarbonate/high‐density polyethylene/ethylene–vinyl acetate copolymer blends
Authors: Pan Ji‐Lin , Li Zhong‐Ming 
Published: December 2007

AbstractA uniaxial tensile test was performed for polycarbonate (PC)/high‐density polyethylene (HDPE)/ethylene–vinyl acetate copolymer (EVA) blends with a fixed EVA content but various PC contents. The double‐yielding phenomenon and its composition dependence, as observed in the PC/HDPE blend, were again detected. EVA did not serve as a successful compatibilizer of PC and HDPE in the PC/HDPE/EVA blend. The incorporation of EVA resulted in a larger size and a more irregular shape of the PC fibers, as indicated in the scanning electron microscope observations; this, consequently, produced a higher serious stress concentration in the blend. This more complicated and instable morphology produced different double‐yielding behaviors in the PC/HDPE/EVA blends compared with the binary one. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2008
Fabrication and characterization of CdTe nanoparticles attached to poly(4‐vinylpyridine) nanofibers
Authors: Wang Shugang , Li Yaoxian , Li Jun , Du Jianshi , Bai Jie , Yang Qingbiao , Chen Xuesi 
Published: December 2007

AbstractThe major objective of this work was to characterize the status of CdTe nanoparticles attached to the surface of poly(4‐vinylpyridine) (P4VP) nanofibers. Scanning electron microscopy and transmission electron microscopy images indicated that the attachment of CdTe nanoparticles enlarged the diameter of P4VP nanofibers. Moreover, the results of the energy‐dispersive X‐ray spectrum and the electron diffraction pattern revealed that the deposition on the surface of P4VP nanofibers was CdTe in a cubic lattice. Furthermore, CdTe existed in its optical style according to photoluminescence spectra. X‐ray photoelectron spectroscopy verified Cd in CdTe nanoparticles combined with the N atom in P4VP nanofibers. Therefore, the obtained results provide some references for preparing coaxial nanofibers attached by other nanoparticles. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2008
Study on the formation process of polyacrylonitrile as‐spun fiber
Authors: Ji Bao‐Hua , Wang Ji‐Hua , Wang Cheng‐Guo , Wang Yan‐Xiang 
Published: December 2007

AbstractIn this article, the coagulation rate of PAN/DMSO dope was studied by observing the boundary movement of the gelled rods in different coagulation bath. Then the effect of the nature of solvent and coagulant and the coagulation conditions on the coagulation rate was discussed. It was found that the molecular size and molecular structure of coagulants is the most significant variable affecting the coagulation rate. The intermolecular affinity between coagulant and solvent determines the activation energy of coagulants, whereas the molecular volume is not a dominant factor. The coagulation rate depends not only on the diffusion coefficient of coagulants but also the nature of solvents. A solvent with strong polarity usually leads to a low‐coagulation rate. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2008