bluuebunny/crossref_metadata_2025 huggingface dataset:
Diffusion properties of reactive dyes into net modified cotton cellulose with triazine derivative
Authors: Xie Kongliang , Sun Yan , Hou Aiqin
Published: November 2006

Cotton fabric is chemically modified with a 1,3,5‐triazine derivative containing multireactive and multicationic groups. The diffusion properties of the reactive dyes into net modified cotton cellulose are investigated. When the dyeing temperature is raised, the dye uptake increases gradually and approaches equilibrium after dyeing for 60 min. The diffusion coefficients at different temperatures and the activation energy of the dye are discussed. Compared with unmodified cellulose, the diffusion kinetics of the dye in the net modified cotton cellulose show significant changes. The activation energies of dyes in net modified cotton fibers are much lower than those of dyes in unmodified cotton. The dyeing behavior of the modified cotton is analyzed and compared with the unmodified cotton. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 103: 2166–2171, 2007
Comparative studies of rheological properties of polyacrylamide and partially hydrolyzed polyacrylamide solutions
Authors: Lewandowska Katarzyna
Published: November 2006

The present work is concerned with experimental results of rheological characteristics of polyacrylamide (PAM) and of partially hydrolyzed polyacrylamide (HPAM) (degree of hydrolysis up to 80%) in aqueous and aqueous/sodium chloride solutions with changing experimental conditions such as polymer concentration, temperature, solvent quality, and shear rate applied. It has been observed that the all‐aqueous and aqueous/NaCl solution of PAM and of HPAM exhibited the non‐Newtonian behavior with shear‐thinning and shear‐thickening areas. The onset of shear‐thickening at $\dot{\rm \gamma}=\dot{\rm \gamma}_c$ depends mainly on the degree of HPAM hydrolysis, as well as on solution concentration, temperature, solvent quality, and polymer molecular weight. Rheological parameters from power law (Ostwald de Waele model) and activation energy of viscous flow (Ea) are determined and discussed. The changes in apparent shear viscosity during aging of solutions of PAM and HPAM are also described. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 103: 2235–2241, 2007
Polymer electrolytes based on poly(ethylene glycol) and cyanoresin
Authors: Oh Kyung Wha , Choi Ji Hyoung , Kim Seong Hun
Published: November 2006

Polymer electrolytes based on a mixed polymer matrix consisting of poly(ethylene glycol) (PEG) and cyanoresins with lithium salt and plasticizer were prepared with an in situ blending process to improve both the mechanical properties and the ionic conductivity (σ). The PEG/lithium perchlorate (LiClO4) complexes, including blends of cyanoethyl pullulan (CRS) and cyanoethyl poly(vinyl alcohol) (CRV), exhibited higher σ's than a simple PEG/LiClO4 complex when the blend compositions of CRS/CRV were 5 : 5 or 3 : 7 or than CRV alone. When the CRS/CRV blend was compared with a copolymer of cyanoethyl pullulan and cyanoethyl poly(vinyl alcohol) (CRM) in the same molar ratio, the σ values of the polymer electrolytes containing the CRM copolymer series were slightly higher than those of the CRS/CRV blends containing PEG/LiClO4 complexes. Moreover, the addition of cyanoresin to PEG/LiClO4/(ethylene carbonate–propylene carbonate) polymer electrolytes provided better thermal stability and dynamic mechanical properties. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 103: 2402–2408, 2007
Silver–polyimide nanocomposite membranes: Macromolecular‐matrix‐mediated metallization of an aromatic, fluorinated polyimide yielding highly reflective films at low metal concentrations
Authors: Davis Luke M. , Thompson D. Scott , Dean C. J. , Pevzner M. , Scott J. L. , Broadwater S. T. , Thompson D. W. , Southward R. E.
Published: November 2006

Highly reflective, surface‐metalized, flexible polyimide films were prepared by the incorporation of a soluble silver‐ion complex, (hexafluoroacetylacetonato)silver(I) (AgHFA), into dimethylacetamide solutions of poly(amic acid) prepared from 2,2‐bis(3,4‐dicarboxyphenyl)hexafluoropropane dianhydride and 2,2‐bis[4‐(4‐aminophenoxy)phenyl]hexafluoropropane. The thermal curing of solution‐cast silver(I)–poly(amic acid) films to 300°C led to cycloimidization of the amic acid with concomitant silver(I) reduction and the formation of a reflective, air‐side‐silvered surface at very low (2 wt % and 0.3 vol %) silver concentrations. The reflective surface evolved only when the cure temperature reached about 275°C, although X‐ray diffraction showed metallic silver in the hybrid film by 200°C. After a maximum specular reflectivity greater than 80% was achieved for the 2 wt % silver film, the specular reflectivity diminished sharply with further heating at a constant temperature of 300°C. Incorporating the AgHFA complex into the soluble, fully imidized form of poly{(1,3‐dihydro‐1,3‐dioxo‐2H‐isoindole‐2,5‐diyl)[2,2,2‐trifluoro‐1‐(trifluoromethyl)ethylidene](1,3‐dihydro‐1,3‐dioxo‐2H‐isoindole‐5,2‐diyl)‐1,4‐phenyleneoxy‐1,4‐phenylene[2,2,2‐trifluoro‐1‐(trifluoromethyl)ethylidene]‐1,4‐phenyleneoxy‐1,4‐phenylene} gave films that were 25% less reflective than those beginning with poly(amic acid). Though highly reflective, the films were not electrically conductive. The metalized membranes were thermally stable and maintained mechanical properties similar to those of the parent polyimide. Transmission electron microscopy revealed an air‐side, near‐surface layer of silver that was about 40 nm thick; the interior of the film had well‐dispersed metal particles with diameters mostly less than 2 nm. The near‐surface silver layer maintained its integrity because of physical entrapment of the metal nanoparticles beneath a thin layer of polyimide; that is, the practical adhesion of the metal layer was good. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 103: 2409–2418, 2007
Isoelectric pH of polyamide–epichlorohydrin modified soy protein improved water resistance and adhesion properties
Authors: Zhong Zhikai , Sun XiuZhi Susan , Wang Donghai
Published: November 2006

Protein macromolecules derived from plants have been considered as alternative resources for various applications, including adhesives, films, rubbers, and biocomposites. Plant protein polymers are pH sensitive and need to be modified to meet application performance. This study demonstrated interactions between polyamide–epichlorohydrin (PAE) and soy protein as affected by pH and temperature. PAE and soy protein molecules formed reversible ionic complexes at room temperature at a pH range of 4–9. The complexation interactions acted as physical crosslinking, which stabilized the soy protein structure and increased its denaturation temperature and enthalpy. The viscosity of adhesives derived from the interaction of PAE and soy protein was affected significantly by the complexation formation, denaturation, and pH. The complexation interactions improved the adhesion properties of the PAE/modified soy protein. pH also played an important role in the adhesion performance, which was attributed to the pH dependence of the protein conformation and PAE/soy protein complexation interactions. © 2006 Wiley Periodicals, Inc. J Appl PolymSci 103: 2261–2270, 2007
Environmentally benign precipitation copolymerization of methacrylate ester and styrene to make polymeric microspheres in supercritical carbon dioxide
Authors: Zhang Donghui , Mishima Kenji , Matsuyama Kiyoshi , Zhou Li , Zhang Shubiao
Published: November 2006

The polymeric microspheres were synthesized by the precipitation copolymerization of glycidyl methacrylate (GMA) with methacrylic acid(MAA) or 2‐hydoxyethyl methacrylate (2‐HEMA) containing styrene (ST) in SC‐CO2. Scanning electron microscopy (SEM) showed that the products were spherical microparticles, with the addition of MAA and/or 2‐HEMA as the monomer, with diameter of 0.2–2 μm. The effects of copolymerization pressure, temperature, and ratios of GMA/MAA, ST, and/or GMA/2‐HEMA, on the particle size and morphology were investigated in detail. A new experiment setup is proposed for the large amount of production, based on the rule of lower monomer concentration, more stable system, and better use of the present polymerization apparatus. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 103: 2425–2431, 2007
Temporal analysis of a very large topically categorized Web query log
Authors: Beitzel Steven M. , Jensen Eric C. , Chowdhury Abdur , Frieder Ophir , Grossman David
Published: November 2006

The authors review a log of billions of Web queries that constituted the total query traffic for a 6‐month period of a general‐purpose commercial Web search service. Previously, query logs were studied from a single, cumulative view. In contrast, this study builds on the authors' previous work, which showed changes in popularity and uniqueness of topically categorized queries across the hours in a day. To further their analysis, they examine query traffic on a daily, weekly, and monthly basis by matching it against lists of queries that have been topically precategorized by human editors. These lists represent 13% of the query traffic. They show that query traffic from particular topical categories differs both from the query stream as a whole and from other categories. Additionally, they show that certain categories of queries trend differently over varying periods. The authors key contribution is twofold: They outline a method for studying both the static and topical properties of a very large query log over varying periods, and they identify and examine topical trends that may provide valuable insight for improving both retrieval effectiveness and efficiency.
Exploratory synthesis of peptide–α‐thioester segments spanning the polypeptide sequence of the δ‐opioid receptor, a G protein‐coupled receptor
Authors: Johnson Erik C. B. , Kent Stephen B. H.
Published: November 2006

We have decided to use the δ‐opioid receptor (372 residues) as a model system to develop methods for the total chemical synthesis of G protein‐coupled receptors. The most important feature of this receptor from a chemical synthesis perspective is the wealth of cysteines spread throughout its sequence, which are required for native chemical ligation. A total of 13 cysteines are located in the the δ‐opioid receptor polypetide chain in both loop and putative transmembrane (TM) regions. We envisioned a synthesis of the polypeptide that would make use of peptide–α‐thioesters ranging from 37 to 63 residues in length. Here, we report data from an exploratory synthesis of such a set of peptide–α‐thioesters. For all seven peptides, the crude material ∼ 30 residues into the synthesis was sufficiently homogeneous to make isolation and purification straightforward. Extension of the peptides to between 40 and 50 residues in length generally produced a significant decrease in the quality of the crude products, although in most cases, we judged that high purity peptides could probably be isolated. By 60 residues, however, the crude peptide product mixtures are probably too heterogeneous to purify to homogeneity by reversed‐phase HPLC. In general, δ‐opioid receptor peptides with a single predicted TM domain were sufficiently soluble to handle postcleavage and to analyze by reversed‐phase HPLC, whereas 1.5 TM domains rendered the peptides too hydrophobic to handle or analyze by standard protocols. Given the challenges of chain assembly, handling, and purification of these peptides, a synthetic strategy that uses ∼ 12 or 13 shorter peptide segments of 20–40 residues each is probably a more feasible approach. © 2006 Wiley Periodicals, Inc. Biopolymers (Pept Sci) 88: 340–349, 2007.

This article was originally published online as an accepted preprint. The “Published Online” date corresponds to the preprint version. You can request a copy of the preprint by emailing the Biopolymers editorial office at biopolymers@wiley.com
Kappa opioid receptors in the rostral ventromedial medulla of male and female rats
Authors: Drake Carrie T. , De Oliveira Andrew X. , Harris Jonathan A. , Connor Denise M. , Winkler Clayton W. , Aicher Sue A.
Published: November 2006

Kappa opioid receptor (KOR) ligands alter nociceptive responses when applied to the rostral ventromedial medulla (RVM). However, the effects of kappa opioid receptor ligands are distinct in males and females. The present study examined the distribution of kappa opioid receptor immunoreactivity in the RVM of male and female rats. KOR immunoreactivity was found at pre‐ and postsynaptic sites within the RVM of both sexes. The most common KOR‐immunoreactive (KOR‐ir) neuronal structures were unmyelinated axons, followed by axon terminals, dendrites, and somata. Different proportions of KOR‐ir axon terminals and dendrites were found in females at different estrous stages. Specifically, dendrites containing KOR immunoreactivity were less abundant in proestrus females compared with estrus females and showed a trend toward being less abundant in males, suggesting that KOR ligands applied to the RVM may be less potent in proestrus females. These findings suggest that the distribution of KORs in the RVM may be influenced by reproductive hormone levels. We also found KOR immunoreactivity in many spinally projecting neurons within the RVM of female rats. These findings are consistent with the hypothesis that KOR ligands influence nociceptive behaviors by altering the activity of specific populations of neurons within the RVM. The abundance of KOR in axons and axon terminals in RVM indicates a substantial role for presynaptic effects of KOR ligands through pathways that have not been clearly delineated. Altering the balance between pre‐ and postsynaptic receptive sites may underlie differences in the effects of KOR agonists on nociceptive responses in males and females. J. Comp. Neurol. 500:465–476, 2007. © 2006 Wiley‐Liss, Inc.
Selective enrichment of DJ‐1 protein in primate striatal neuronal processes: Implications for Parkinson's disease
Authors: Olzmann James A. , Bordelon Jill R. , Muly E. Chris , Rees Howard D. , Levey Allan I. , Li Lian , Chin Lih‐Shen
Published: November 2006

Mutations in DJ‐1 cause autosomal recessive, early‐onset Parkinson's disease (PD). The precise function and distribution of DJ‐1 in the central nervous system remain unclear. In this study, we performed a comprehensive analysis of DJ‐1 expression in human, monkey, and rat brains with antibodies that recognize distinct, evolutionarily conserved epitopes of DJ‐1. We found that DJ‐1 displays region‐specific neuronal and glial labeling in human and nonhuman primate brain, sharply contrasting with the primarily neuronal expression pattern observed throughout rat brain. Further immunohistochemical analysis of DJ‐1 expression in human and nonhuman primate brains showed that DJ‐1 protein is expressed in neurons within the substantia nigra pars compacta and striatum, two regions critically involved in PD pathogenesis. Moreover, immunoelectron microscopic analysis revealed a selective enrichment of DJ‐1 within primate striatal axons, presynaptic terminals, and dendritic spines with respect to the DJ‐1 expression in prefrontal cortex. Together, these findings indicate neuronal and synaptic expression of DJ‐1 in primate subcortical brain regions and suggest a physiological role for DJ‐1 in the survival and/or function of nigral‐striatal neurons. J. Comp. Neurol. 500:585–599, 2007. © 2006 Wiley‐Liss, Inc.
When controversial leaders with charisma are effective: the influence of terror on the need for vision and impact of mixed attitudinal messages
Authors: Gordijn Ernestine H. , Stapel Diederik A.
Published: November 2006

We investigated the idea that a charismatic leader with a controversial message is most likely to persuade people in times of terror, because in those times people have a high need for vision, and vision is what a charismatic leader provides. In addition, we argued that the leader's message should contain a pro‐attitudinal position as well, as this makes the counter‐attitudinal message more palatable. In line with our hypotheses, we found in Experiment 1 that thinking about terrorism increases people's need for vision. Experiment 2 revealed that only when people have a high need for vision they will be influenced by a controversial charismatic leader. Experiment 3 showed that existential threats also directly increase the influence of a controversial charismatic leader. Further, this was especially so when the charismatic leader was both attractive and communicated his message in a charismatic way. Finally, Experiment 4 revealed that after thinking about their own death or about terrorist attacks, people were most likely to be persuaded by a controversial charismatic leader whose counter‐attitudinal message also contained pro‐attitudinal statements. Together, this research suggests that in times of terror people's need for vision increases, which opens them up to a counter‐attitudinal message of a charismatic leader as long as this message also includes some pro‐attitudinal statements. Copyright © 2006 John Wiley & Sons, Ltd.
Usefulness of microchip electrophoresis for the analysis of mitochondrial DNA in forensic and ancient DNA studies
Authors: Alonso Antonio , Albarran Cristina , Martín Pablo , García Pilar , Capilla Javier , García Oscar , de la Rua Concepción , Izaguirre Neskuts , Pereira Filipe , Pereira Luisa , Amorim António , Sancho Manuel
Published: November 2006

We evaluate the usefulness of a commercially available microchip CE (MCE) device in different genetic identification studies performed with mitochondrial DNA (mtDNA) targets, including the haplotype analysis of HVR1 and HVR2 and the study of interspecies diversity of cytochrome b (Cyt b) and 16S ribosomal RNA (16S rRNA) mitochondrial genes in forensic and ancient DNA samples. The MCE commercial system tested in this study proved to be a fast and sensitive detection method of length heteroplasmy in cytosine stretches produced by 16 189T>C transitions in HVR1 and by 309.1 and 309.2 C‐insertions in HVR2. Moreover, the quantitative analysis of PCR amplicons performed by LIF allowed normalizing the amplicon input in the sequencing reactions, improving the overall quality of sequence data. These quantitative data in combination with the quantification of genomic mtDNA by real‐time PCR has been successfully used to evaluate the PCR efficiency and detection limit of full sequencing methods of different mtDNA targets. The quantification of amplicons also provided a method for the rapid evaluation of PCR efficiency of multiplex‐PCR versus singleplex‐PCR to amplify short HV1 amplicons (around 100 bp) from severely degraded ancient DNA samples. The combination of human‐specific (Cyt b) and universal (16S rRNA) mtDNA primer sets in a single PCR reaction followed by MCE detection offers a very rapid and simple screening test to differentiate between human and nonhuman hair forensic samples. This method was also very efficient with degraded DNA templates from forensic hair and bone samples, because of its applicability to detect small amplicon sizes. Future possibilities of MCE in forensic DNA typing, including nuclear STRs and SNP profiling are suggested.
Informative‐Transmission Disequilibrium Test (i‐TDT): combined linkage and association mapping that includes unaffected offspring as well as affected offspring
Authors: Guo Chao‐Yu , Lunetta Kathryn L. , DeStefano Anita L. , Ordovas Jose M. , Adrienne Cupples L.
Published: November 2006

To date, there is no test valid for the composite null hypothesis of no linkage or no association that utilizes transmission information from heterozygous parents to their unaffected offspring as well as the affected offspring from ascertained nuclear families. Since the unaffected siblings also provide information about linkage and association, we introduce a new strategy called the informative‐transmission disequilibrium test (i‐TDT), which uses transmission information from heterozygous parents to all of the affected and unaffected offspring in ascertained nuclear families and provides a valid chi‐square test for both linkage and association. The i‐TDT can be used in various study designs and can accommodate all types of independent nuclear families with at least one affected offspring. We show that the transmission/disequilibrium test (TDT) (Spielman et al. [1993] Am. J. Hum. Genet. 52:506–516) is a special case of the i‐TDT, if the study sample contains only case‐parent trios. If the sample contains only affected and unaffected offspring without parental genotypes, the i‐TDT is equivalent to the sibship disequilibrium test (SDT) (Horvath and Laird [1998] Am. J. Hum. Genet. 63:1886–1897. In addition, the test statistic of i‐TDT is simple, explicit and can be implemented easily without intensive computing. Through computer simulations, we demonstrate that power of the i‐TDT can be higher in many circumstances compared to a method that uses affected offspring only. Applying the i‐TDT to the Framingham Heart Study data, we found that the apolipoprotein E (APOE) gene is significantly linked and associated with cross‐sectional measures and longitudinal changes in total cholesterol. Genet. Epidemiol. © 2006 Wiley‐Liss, Inc.
Interpretation of simultaneous linkage and family‐based association tests in genome screens
Authors: Chung Ren‐Hua , Hauser Elizabeth R. , Martin Eden R.
Published: November 2006

Linkage and association analyses have played important roles in identifying susceptibility genes for complex diseases. Linkage tests and family‐based tests of association are often applied in the same data to help fine‐map disease loci or validate results. This paradigm increases efficiency by making maximal use of family data sets. However, it is not intuitively clear under what conditions association and linkage tests performed in the same data set may be correlated. Understanding this relationship is important for interpreting the combined results of both tests. We used computer simulations and theoretical statements to estimate the correlation between linkage statistics (affected sib pair maximum LOD scores) and family‐based association statistics (pedigree disequilibrium test (PDT) and association in the pressure of linkage (APL)) under various hypotheses. Different types of pedigrees were studied: nuclear families with affected sib pairs, extended pedigrees and incomplete pedigrees. Both simulation and theoretical results showed that when there is no linkage or no association, the linkage and association tests are not correlated. When there is linkage and association in the data, the two tests have a positive correlation. We concluded that when linkage and association tests are applied in the same data, the type I error rate of neither test will be affected and that power can be increased by applying tests conditionally. Genet. Epidemiol. © 2006 Wiley‐Liss, Inc.
Down‐regulation of S100A2 in lymph node metastases of head and neck cancer
Authors: Zhang Xin , Hunt Jennifer L. , Shin Dong M. , Chen Zhuo (Georgia)
Published: November 2006

Background.

Our cDNA microarray analysis of squamous cell carcinoma of the head and neck (SCCHN) previously identified that S100A2 was down‐regulated in highly metastatic 686LN‐M3s cell lines established through in vivo selection using a metastatic xenograft mouse model. S100A2, a putative tumor suppressor, has been found to be down‐regulated in several types of primary tumor as compared with the normal tissue. Only a few reports have explored its expression status and function in metastasis.

Methods.

To further confirm down‐regulation of S100A2 in human metastasis, we examined S100A2 expression using immunohistochemical analysis of paraffin‐embedded SCCHN tissues. The samples included primary SCCHN tumors (Tu‐1) and involved lymph nodes (Met‐1) from the same patients, and primary tumors in node‐negative patients (Tu‐2).

Results.

Most of these tumors expressed S100A2 but lymph node metastases showed a pattern of reduced staining for S100A2 compared with primary tumors. A similar expression pattern of S100A2 was also observed in several SCCHN cell lines by reverse transcription‐polymerase chain reaction (RT‐PCR) and immunoblotting. Particularly, S100A2 expression was lower in 686LN than Tu686 and hardly detectable in the metastatic derivatives 686LN‐M3s. Further study of S100A2 promoter showed higher methylation intensity in these metastatic derivatives than in Tu686 and 686LN.

Conclusions.

S100A2 was down‐regulated in lymph node metastasis of SCCHN, suggesting that instead of being a putative tumor suppressor, S100A2 may play a role in the metastasis of SCCHN. © 2006 Wiley Periodicals, Inc. Head Neck, 2007
Quality of integrated care for patients with head and neck cancer: Development and measurement of clinical indicators
Authors: Ouwens Mariëlle M. M. T. J. , Marres Henri A. M. , Hermens Rosella R. P. , Hulscher Marlies M. E. , van den Hoogen Frank J. A. , Grol Richard P. , Wollersheim Hub C. H.
Published: November 2006

Background.

To improve the quality of integrated care, we developed indicators for assessing current practice in a large reference center for head and neck oncology.

Methods.

We defined a set of indicators based on integrated care literature, national evidence‐based guidelines for patients with head and neck cancer, and the opinions of professionals and patients. We tested this set regarding assessement of current practice and clinimetric characteristics.

Results.

The final set consisted of 8 integrated care indicators and 23 specific indicators for patients with head and neck cancer. Current practice assessment produced high scores for the integrated care indicators, but the specific indicators showed room for improvement. The practice test showed that 9 indicators had good applicability.

Conclusions.

The indicators, while based on evidence‐based guidelines and the principles of integrated care, should incorporate patients' opinions and include a practice test. Our results show that the quality of integrated care for patients with head and neck cancer could be improved. © 2006 Wiley Periodicals, Inc. Head Neck, 2007
Screening for local and regional cancer recurrence in patients curatively treated for laryngeal cancer: Definition of a high‐risk group and estimation of the lead time
Authors: Ritoe Savitri C. , Verbeek André L. M. , Krabbe Paul F. M. , Kaanders Johannes H. A. M. , van den Hoogen Frank J. A. , Marres Henri A. M.
Published: November 2006

Background.

All patients treated for laryngeal cancer are offered the same follow‐up schedule to detect asymptomatic locoregional recurrences. In this study, we evaluated the prognostic profile of patients for cancer recurrence and estimated the lead time.

Methods.

A cohort study was performed between 1990 and 1995. Cox proportional hazards model was used to analyze the prognostic factors. The effect of altering the follow‐up for asymptomatic recurrence detection was determined after estimating the lead time.

Results.

The variables cT classification, smoking, and histologic grade proved to be prognostic factors. The risk of locoregional failure was 15% in the low‐risk group versus 29% in the high‐risk group. The estimated lead time was 2 to 4 weeks.

Conclusion.

Risk profiles for locoregional relapse were defined. Intensifying the follow‐up schedule is not advisable because the lead time is very short. An excessively high number of routine visits would have to be performed to increase the detection rate for asymptomatic recurrences. © 2006 Wiley Periodicals, Inc. Head Neck, 2007
The effect of human resource management practices on the job retention of former welfare clients
Authors: Deckop John R. , Konrad Alison M. , Perlmutter Felice Davidson , Freely Joshua L.
Published: November 2006

Why should an employer hire a former welfare client?What human resource management practices can help employers retain former welfare clients? This study addresses these questions against the backdrop of changes in welfare legislation in the United States that have lessened support to welfare clients and their families and emphasized movement into the workplace. We conducted a large‐scale empirical study of the effectiveness of a wide range of HRM practices and found that higher wages, better financial and health benefits, and development opportunities were positively associated with job retention. Unexpectedly, supervisory training had no relationship to retention, and appraising supervisors on providing a supportive and inclusive work environment showed a negative relationship. We provide suggestions to employers for improving the job retention of former welfare recipients along with directions for additional research. © 2006 Wiley Periodicals, Inc.
Workforce reduction and job‐seeker attraction: Examining job seekers' reactions to firm workforce‐reduction policies
Authors: Kammeyer‐Mueller John , Liao Hui
Published: November 2006

Empirical research and narrative reports from working managers suggest that employee attitudes can be negatively influenced by organizational downsizing, but the potential impact of downsizing on applicants is not well documented. In this study, we investigate the effect of organizational downsizing on job‐seeker attraction to an organization. Respondents were given descriptions of two organizations, coupled with information on workforce reductions in the two organizations. We found that workforce reductions reduced job‐seeker attraction. However, companies that downsized but provided assistance and adequate communication to employees were nearly as attractive to applicants as companies that had not downsized. Managerial implications of these results are provided. © 2006 Wiley Periodicals, Inc.
Organizationally sensible versus legal‐centric approaches to employment decisions
Authors: Roehling Mark V. , Wright Patrick M.
Published: November 2006

Many managers and human resource professionals view the law increasingly as an overly restrictive influence on their ability to manage employees effectively. This article is intended to alert HR professionals to the risk that they are unnecessarily contributing to the impact that legal considerations have on the management of employees as a result of “legal‐centric decision making.” We introduce the construct of legal‐ centric decision making, present a model of the primary factors contributing to legal‐centric decision making, provide support for the model from diverse literatures (e.g., behavioral decision making, management, and law), and identify several keys to avoiding legal‐ centric decision making. © 2006 Wiley Periodicals, Inc.
Modelling climate change impacts in the Peace and Athabasca catchment and delta: I—hydrological model application
Authors: Toth Brenda , Pietroniro Alain , Conly F. Malcolm , Kouwen Nicholas
Published: November 2006

The Peace–Athabasca Delta (PAD) is an extensive freshwater delta fed by the confluence of the Peace and Athabasca rivers. The Peace River, with regulation at the W.A.C. Bennett Dam, has a direct influence on the hydrology and eco‐hydrology of the PAD. To investigate the relative roles of climate variability and flow regulation, the Peace and Athabasca watershed and delta were simulated using a distributed hydrologic model, WATFLOOD. The model was forced using historical, station‐observed data as well as climate change scenario temperature and precipitation data. The modelled hydrographs over the 24‐year simulation period were compared with measured values at the 14 streamflow stations with generally good agreement for volume and timing of flow, monthly estimates having a Nash–Sutcliffe (R2) of 0·76 and 0·72 for the Peace and Athabasca Rivers, respectively. However, the total of the monthly runoff estimates were positively biased by 19% and 29%, respectively (Peace River at Peace Point, Dv = 19%, Athabasca River at Ft. McMurray Dv = 29%). A comparison between estimated current and future climate scenarios revealed a significant shift towards an earlier melt season as well as elevated winter flows for both river systems. The uniform application of temperature and precipitation change yields a non‐uniform response. The lower elevations of the Athabasca system show trends towards increased streamflow volumes; however, the higher elevations of the Peace River system may experience increased evaporative flux which will more fully compensate for higher precipitation resulting in only slightly increased streamflow under changed climate. The degree and direction of estimated change in streamflow are heavily dependant on the climate change scenario. Copyright © 2006 Crown in the right of Canada. Published by John Wiley & Sons, Ltd.
Modelling climate change impacts in the Peace and Athabasca catchment and delta: III—integrated model assessment
Authors: Pietroniro Alain , Leconte Robert , Toth Brenda , Peters Daniel L. , Kouwen Nicholas , Conly F. Malcolm , Prowse Terry
Published: November 2006

This study utilized the hydrodynamic model, ONE‐D, coupled to the distributed hydrological model WATFLOOD, to evaluate the potential effects of a shift in climate on the hydrological regimes of three large lakes (Athabasca, Claire, and Mamawi), and two important sources of inflow (the Peace and Athabasca rivers) in the Peace‐Athabasca Delta (PAD). The coupled WATFLOOD/ONE‐D system was forced by current climatology and downscaled climate change scenarios from five selected general circulation models (GCMs).

Under the selected climate change scenarios, water levels in Lakes Athabasca, Claire, and Mamawi peaked, on average, 40–50 days earlier than at present. Some GCM scenarios predicted an increase in peak lake levels while others predicted suppressed lake levels. Inter‐annual water level variability was also sensitive to predicted changes in precipitation and temperature, increasing in winter and decreasing in summer.

Water level fluctuations in the major input rivers of the PAD were found to be more variable under the climate change simulations. Moreover, spring freshet peaks were estimated to occur earlier (20–30 days) and to be considerably reduced (up to 1·0 m reductions).

Although the simulations converged towards the same general results in seasonality shift, flow level amplitude was GCM‐dependent. Simple downscaling methods may well be too coarse to adequately address the important spatial variations that can occur in the long‐term climate signal. It is therefore important to understand the sensitivity of this regime to local climatic influences to produce more reliable, quantitative results. An ensemble of approaches that provide meaningfully downscaled results should be considered to confirm the results presented. Copyright © 2006 Crown in the right of Canada, and John Wiley & Sons, Ltd.
Expression of vascular endothelial growth factor and its receptors in the porcine corpus luteum during the estrous cycle and early pregnancy
Authors: Kaczmarek Monika M. , Kowalczyk Anna E. , Waclawik Agnieszka , Schams Dieter , Ziecik Adam J.
Published: November 2006

The present study was undertaken to determine the expression of vascular endothelial growth factor (VEGF) and its receptors, fms‐like tyrosine kinase (Flt‐1) and fetal liver kinase‐1/kinase insert domain‐containing receptor (Flk‐1/KDR), in the porcine corpus luteum (CL) during the estrous cycle and early pregnancy. Immunohistochemical studies localized proteins of VEGF ligand‐receptor system in the cytoplasm of luteal cells and in some blood vessels. Western blot analysis revealed significantly higher levels of VEGF protein during early and mid‐luteal phase (vs. late luteal phase; P < 0.001 and P < 0.01, respectively). Quantification of VEGF mRNA in the CL showed increased mRNA levels during entire luteal phase (vs. Days 16–17; P < 0.05). Expression of Flt‐1 protein remained high during luteal phase (P < 0.001), but the mRNA levels tended to increase from the early to the late luteal phase. Elevated protein expression of Flk‐1/KDR was found in the mid‐luteal phase (vs. Days 16–17; P < 0.05). However, induction of Flk‐1/KDR mRNA expression occurred earlier, in early luteal phase. The lowest VEGF, Flt‐1 and Flk‐1/KDR mRNA and protein levels were observed in regressed CL (P < 0.001). During pregnancy, VEGF, Flt‐1 and Flk‐1/KDR mRNA and protein expression was comparable to the mid‐luteal phase. In conclusion, the present study has demonstrated dynamic expression of VEGF and its receptors in the porcine CL during the estrous cycle and early pregnancy. These data suggest that the VEGF ligand‐receptor system may play an important role in the development and maintenance of the CL in pigs. Mol. Reprod. Dev. 74: 730–739, 2007. © 2006 Wiley‐Liss, Inc.
Elastic waves at a corrugated interface between two dissimilar fibre‐reinforced elastic half‐spaces
Authors: Sarat Singh Sanasam , Tomar S. K.
Published: November 2006

The reflection and transmission phenomena of elastic waves incident at a corrugated interface between two dissimilar fibre‐reinforced elastic half‐spaces have been analysed. Using Rayleigh method of approximation, the expressions of the reflection and transmission coefficients are obtained in closed form for the plane interface as well as for the first order approximation of the periodic interface ζ = d cos px. All these reflection and transmission coefficients of regular and irregular waves are found to be the functions of angle of incidence and elastic parameters of the media. Moreover, the coefficients of irregularly reflected and transmitted waves are found to be proportional to the amplitude of the corrugated interface and are functions of the frequency of the incident wave. Numerical computations have been performed for a specific model to compute these coefficients and results obtained are shown graphically. The results of Singh and Singh (Sadhana 2004; 29:249–257) and Ben‐Menahem and Singh (Seismic Waves and Sources. Springer: New York) have been derived from our analysis as particular cases. Copyright © 2006 John Wiley & Sons, Ltd.
Interpretation of dilatometer tests in a heavy oil reservoir
Authors: Dano Christophe , Hicher Pierre‐Yves , Rangeard Damien , Marchina Philippe
Published: November 2006

This paper presents a prospective study for identifying selected parameters of the modified Cam‐Clay model representing the behaviour of heavy oil reservoirs. The first part shows that the plastic compressibility, which controls the main recovery mechanism of such reservoirs, can be accurately determined, simultaneously with other parameters, by an inverse analysis of pressure–strain curves. The conditions of the identification procedure mainly involve two tests conducted under different drainage conditions or at different strain rates. The numerical study also establishes the sequence of an original in situ experimental program, in which three dilatometer tests at a relatively great depth (several hundreds of metres) were carried out. The comparison of the experimental data with the numerical computations reveals a significant over‐consolidation ratio which does not allow the plastic compressibility to be determined but supports the findings regarding the geological erosion of the site. Copyright © 2006 John Wiley & Sons, Ltd.
M2mediated contractions of human bladder from organ donors is associated with an increase in urothelial muscarinic receptors
Authors: Braverman Alan S. , Lebed Brett , Linder Mitchell , Ruggieri Michael R.
Published: November 2006

Aims

Previous studies have shown increased density of M2receptors in hypertrophied rat bladders that possess an M2contractile phenotype. The aim of the current study is to determine whether human bladders with an M2contractile phenotype also have a greater density of bladder M2receptors.

Materials and Methods

Human bladders were obtained from 24 different organ transplant donors. Darifenacin and methoctramine affinity was determined by the rightward shift of cumulative carbachol concentration contractile response curves for each bladder. Radioligand binding and immunoprecipitation was used to quantify M2and M3subtypes in isolated detrusor muscle and urothelium. In addition, pig bladder muscle and urothelial receptors were quantified for comparison.

Results

In the human urothelium total, M2and M3muscarinic receptor density is significantly negatively correlated with the affinity of darifenacin for inhibition of contraction of the detrusor muscle. In the detrusor muscle there is no correlation between receptor density and darifenacin affinity for inhibition of contraction. Muscarinic receptor density is greater in the muscle than in the urothelium in human bladders whereas in the pig bladder the density is greater in the urothelium than in the muscle.

Conclusions

The greater density of urothelial muscarinic receptors in human bladders with lower darifenacin affinity, indicative of a greater contribution of M2receptors to the contractile response, points towards a possible role of the urothelium in controlling M2mediated contractile phenotype. In comparison between human and pig bladders, the distribution of muscarinic receptor subtypes in the muscle and urothelium are quite different. Neurourol. Urodynam. © 2006 Wiley‐Liss, Inc.
Approximation algorithm for the group Steiner network problem
Authors: Penn Michal , Rozenfeld Stas
Published: November 2006

In this article we study the group Steiner network problem, which is defined in the following way. Given a graph G = (V,E), a partition of its vertices into K groups and connectivity requirements between the different groups, the aim is to find simultaneously a set of representatives, one for each group, and a minimum cost connected subgraph that satisfies the connectivity requirements between the groups (representatives). This problem is a generalization of the Steiner network problem and the group Steiner tree problem, two known NP‐complete problems. We present an approximation algorithm for a special case of the group Steiner network problem with an approximation ratio of min {2(1 + 2x),2I}, where I is the cardinality of the largest group and x is a parameter that depends on the cost function. © 2006 Wiley Periodicals, Inc. NETWORKS, Vol. 49(2), 160–167 2007
Fabrication and characterization of microdisk resonators with In(Ga)As/GaAs quantum dots
Authors: Rastelli A. , Ulhaq A. , Deneke Ch. , Wang L. , Benyoucef M. , Coric E. , Winter W. , Mendach S. , Horton F. , Cavallo F. , Merdzhanova T. , Kiravittaya S. , Schmidt O. G.
Published: November 2006

We report on the fabrication and characterization of GaAs‐based microdisk resonators containing lowsurface‐density self‐assembled In(Ga)As quantum dots. Microdisks of different sizes are obtained by optical and electron‐beam lithography followed by a two‐step wet chemical etching. The use of wet etching results in smooth disk edges. The optical properties of the quantum dots and microdisks are studied by microphotoluminescence spectroscopy as a function of excitation power. Disks with quality factors larger than 12000 (resolution limited spectral width) are easily obtained with the described approach even with optical lithography. Laser heating of microdisks is also discussed. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Entangled photon pairs from a quantum dot source
Authors: Stevenson R. M. , Young R. J. , Atkinson P. , Cooper K. , Ritchie D. A. , Shields A. J.
Published: November 2006

We present the results of recent experiments designed to manipulate the splitting in quantum dots, to eradicate the which‐path information that prevents entangled photon emission. We demonstrate that dots with splitting within the homogeneous linewidth can be grown directly by carefully controlling the thickness of the dot layer. Polarization dependent correlation measurements on these dots show characteristic features of entanglement, only present for dots with small splitting. Our results indicate that for the first time, we have observed triggered entangled photon pair emission from a quantum dot. The ability to trigger the emission of just one photon pair has advantages over other schemes to generate entangled photons, including scalability of the applications. Finally, we note that the device, once optimized, could be implemented by a simple LED‐like structure. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Pauli blockade transport in the cotunneling regime through a double quantum dot
Authors: Liu H. W. , Fujisawa T. , Hayashi T. , Hirayama Y.
Published: November 2006

Pauli spin blockade in the cotunneling transport through an effective two‐electron double quantum dot (™10 electrons in each dot) has been presented. In the cotunneling regime where the two‐electron (1,1) and (0,2) states (ordered pairs denote the effective electron numbers in each dot) are far below the Fermi energy of the leads, we can concentrate on the two‐electron tunnelling transitions and detect singlet‐triplet splitting arising from the exchange interaction between the two electron spins with improved resolution. We discuss the cotunneling transport by considering the coherent and incoherent coupling between the dots in connection with the singlet‐triplet splitting. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
CdSe/ZnSe quantum dots coupled to modes of monolithic II‐VI pillar microcavities: tunability and Purcell effect
Authors: Lohmeyer H. , Kruse C. , Sebald K. , Gutowski J. , Hommel D.
Published: November 2006

The emission properties of CdSe/ZnSe quantum dots embedded in high‐Q all‐epitaxial ZnSe‐based pillar microcavities are studied. Temperature variable experiments show a strong enhancement of the detected photoluminescence signal of single quantum dots when tuned in resonance with modes of the cavity. The Purcell effect is reflected in a pronounced enhancement of the spontaneous emission rate of quantum dots coupling to the fundamental modes of the cavities. The dependence of the enhancement on the pillar diameter is discussed in detail. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
1.3–1.6 µm broadband polarization‐independent luminescence by columnar InAs quantum dots on InP(001)
Authors: Kawaguchi Kenichi , Ekawa Mitsuru , Yasuoka Nami , Akiyama Tomoyuki , Ebe Hiroji , Sugawara Mitsuru , Arakawa Yasuhiko
Published: November 2006

Columnar InAs quantum dots (QDs) with polarization‐independent luminescence were formed on InP(001) by metalorganic vapor‐phase epitaxy. Self‐assembled small QDs with lateral sizes of around 20 nm were formed by using a low growth temperature of 430 °C. Columnar QDs with heights comparable to their lateral sizes were formed by closely stacking the small QDs with tensile‐strained InGaAsP barriers. Polarized‐independent photoluminescence was obtained for a broadband of 1.3–1.6 µm at room temperature. These QDs promise to provide polarization‐insensitive semiconductor optical amplifiers. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Fock‐Darwin spectrum of a single InAs/GaAs quantum dot
Authors: Babinski A. , Potemski M. , Raymond S. , Lapointe J. , Wasilewski Z. R.
Published: November 2006

Magnetospectroscopic study of a highly excited single InAs/GaAs quantum dot is reported. Optical emission from the s‐ and p‐shells is identified and investigated in magnetic fields up to 20T. The zero‐field splitting and the Zeeman orbital splitting of the p‐shell‐related emission lines in magnetic field are observed. The evolution of spectra in magnetic field resembles a classical Fock‐Darwin energy diagram, although effects of the electron‐electron interaction and asymmetry of localizing potential can be clearly observed. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Phonon‐assisted transport through a double quantum dot: magnetic field dependence in a spin blockade regime
Authors: Iñarrea Jesús , Platero Gloria , MacDonald Allan H.
Published: November 2006

We analyze the electronic transport through a double quantum dot in the regime where spin blockade occurs. Experiments of current rectification by Pauli exclusion principle in double quantum dots are discussed. Our model includes a self‐consistent description of inelastic transitions where the energy is exchanged through interactions with acoustic phonons in the environment. It accounts for spontaneous emission of phonons which results in additional features in the current characteristics as observed experimentally due to the opening of new current channels. We show as well how a magnetic field applied parallel to the current allows excited states to participate in the electronic current and removes spin blockade. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)