bluuebunny/crossref_metadata_2025_split huggingface dataset:
Hyperbranched and thermally cross‐linkable oligomer from a new 2,5,7‐tri‐functional fluorene monomer
Authors: Tsai Lin‐Ren , Chen Yun 
Published: November 2007

AbstractNew hyperbranched (HOFV) and linear oligomers (LOFV) were prepared from 2‐bromo‐5,7‐divinyl‐9,9‐dihexylfluorene (AB2) and 2‐bromo‐7‐vinyl‐9,9‐dihexylfluorene, respectively, by the Heck reaction to study the effect of hyperbranched structure. The oligomers were readily soluble in common organic solvents. The weight‐average molecular weights (Mw) of HOFV and LOFV, determined by gel permeation chromatography using polystyrene as standard, were 2350 and 3950, respectively. Optical properties, both in solution and film state, were investigated using absorption and photoluminescence (PL) spectra. In film state, the absorption and PL spectra peaked at 416 ∼ 425 nm and 473 ∼ 503 nm, respectively. The HOFV showed energy funnel effect and enhanced fluorescence efficiency owing to the hyperbranched structure. The HOMO and LUMO levels of HOFV (LOFV), estimated from their cyclic voltammograms, were −5.25 (−5.34) eV and −2.66 (−2.75) eV, respectively. Thermal curing of HOFV to form cross‐linked HPFV (hyperbranched poly(fluorenevinylene)) was studied by IR, DSC, UV–visible spectra, NMR, AFM and SEM. The terminal vinyl groups in HOFV film almost disappeared to provide smooth, homogeneous and solvent‐resistant films of HPFV. Two‐layer PLED devices (ITO/PEDOT/HPFV/Ca/Al) exhibited maximal luminance and luminous efficiency of 1480 cd/m2 and 0.18 cd/A, respectively, which were superior to its linear counterpart LPFV (352 cd/m2, 0.06 cd/A). © 2007 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 46: 70–84, 2008
Combining atom‐transfer radical polymerization and ring‐opening polymerization through bifunctional initiators derived from hydroxy benzyl alcohol—Preparation and characterization of initiators, macroinitiators, and block copolymers
Authors: Likhitsup Asawin , Parthiban Anbanandam , Chai Christina L. L. 
Published: November 2007

AbstractA simple, one‐step procedure has been developed for the preparation of bifunctional initiators capable of polymerizing monomers suitable for atom‐transfer radical polymerization (ATRP) and ring‐opening polymerization (ROP). These bifunctional initiators were employed for making narrow disperse poly(styrene) macroinitiators, which were subsequently used for the ROP of various lactides to yield poly(styrene‐block‐lactide) copolymers. Thermogravimetric analysis (TGA) of these block copolymers are interesting in that it shows a two‐step degradation curve with the first step corresponding to the degradation of poly(lactide) segment and the second step associated with the poly(styrene) segment of the block copolymer. This nature of the block copolymer makes it possible to estimate the block copolymer content by TGA in addition to the 1H NMR spectroscopic analysis. Thus, this study for the first time highlights the possibility of making porous materials by thermal means which are otherwise obtained by base hydrolysis. The bifunctional initiators were prepared by the esterification of 3‐hydroxy, 4‐hydroxy, and 3,5‐dihydroxy benzyl alcohols with α‐bromoisobutyryl bromide and 2‐bromobutyryl bromide. A mixture of products was obtained, which were purified by column chromatography. The esterified benzyl alcohols were employed in the polymerization of styrene under copper (Cu)‐catalyzed ATRP conditions to yield macroinitiators with low polydispersity. These macroinitiators were subsequently used in the ROP of L‐, DL‐, and mixture of lactides. The formation of block copolymers was confirmed by gel permeation chromatography (GPC), spectroscopic and thermal characterizations. The molecular weight of the block copolymers was always higher than the macroinitiator, and the GPC chromatogram was symmetrical indicating the uniform initiation of ROP by the macroinitiators. © 2007 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 46: 102–116, 2008
Graft block copolymers of propargyl methacrylate and vinyl acetate via a combination of RAFT/MADIX and click chemistry: Reaction analysis
Authors: Quémener Damien , Hellaye Maude Le , Bissett Carla , Davis Thomas P. , Barner‐Kowollik Christopher , Stenzel Martina H. 
Published: November 2007

AbstractPropargyl methacrylate with its acetylene function protected with a silyl group is polymerized via the reversible addition fragmentation chain transfer (RAFT) process, using cyanoisopropyl dithiobenzoate (CPDB) as RAFT agent, and subsequently deprotected to afford a polymer backbone where each repeated unit is decorated with an acetylene functionality (1000 < Mn < 13,600 g mol−1, 1.07 < PDI < 1.29). In parallel, an azide functionalized xanthate (ethoxythiocarbonylsulfanyl‐acetic acid 3‐azido‐propyl ester) was employed to prepare narrow polydisperse poly(vinyl acetate) (Mn = 850 g mol−1, PDI = 1.20). The two polymers are conjugated by Huisgen 1,3‐dipolar cycloaddition to afford narrow polydisperse comb polymer (1.12 < PDI < 1.18, 3400 < Mn < 12,500 g mol−1, based on linear polystyrene calibration, 4500 < M < 15,600 g mol−1). The study places special emphasis on following the copper catalyzed 1,3‐dipolar cycloaddition via Fourier Transform Infrared Spectroscopy (FTIR) as well as via on‐line UV–Vis photospectrometry on several model compounds, i.e. the nonmonomer inserted azido‐xanthate RAFT/MADIX agent as well as a 2‐propargyl‐2‐bromopropionate and 3‐azidopropyl‐2‐bromopropionate model compounds. A suitable absorption band in the VIS at 666 nm (tentatively assigned to a charge transfer complex between copper(I) and the forming triazole moieties) is identified as a promising sensor for following the click reaction kinetics, thus allowing for the rapid assessment of reaction completion in an on‐line fashion. © 2007 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 46: 155–173, 2008
Preparation and characterization of 1,2,3‐triazole‐cured polymers from endcapped azides and alkynes
Authors: Katritzky Alan R. , Meher Nabin K. , Hanci Sureyya , Gyanda Reena , Tala Srinivasa R. , Mathai Sindhu , Duran Randolph S. , Bernard Sophie , Sabri Firouzeh , Singh Sandeep K. , Doskocz Jacek , Ciaramitaro David A. 
Published: November 2007

AbstractFourteen commercial polyols have been characterized by GPC, NMR spectroscopy, and elemental analysis. From these, eight corresponding tosylates, six nitrate esters, seven mesylates, 13 alkynes, and 14 azides have been prepared and all these derivatives have been fully characterized. Five alkyne monomers and eight azide monomers were also prepared. Twelve alkynes and 13 azides (functionality 2–4) were combined in 1,3‐dipolar cycloaddition reactions under neat conditions to prepare triazole‐cured polymers, avoiding any heavy metal catalyst. Characterization by NMR spectroscopy, elemental analysis, and gel permeation chromatography indicated triazole polymers 14, 22, 23, 28, and 30 with degrees of polymerization of 17–28 to be the best candidates for future work. © 2007 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 46: 238–256, 2008
‘If we get too close to your bones they'll go brittle’: women's initial fears about radiotherapy for early breast cancer
Authors: Halkett Georgia K. B. , Kristjanson Linda J. , Lobb Elizabeth A. 
Published: November 2007

AbstractIntroduction: Radiotherapy is a common treatment for breast cancer. However, previous studies have shown that women who present for radiotherapy fear its use and associated side effects. The aims of this study were to develop further understanding of breast cancer patients' fears of radiotherapy, ascertain how patients deal with these fears and determine the best time in the treatment planning trajectory for health professionals to address these concerns.Methods: Semi‐structured interviews were conducted with early breast cancer patients at four time points during their experiences of radiotherapy. Grounded theory was used to analyse the data. Symbolic interactionism informed data interpretation.Results: Thirty‐four participants were interviewed. The two main themes that emerged prior to treatment commencement were ‘fears about receiving radiotherapy’ and ‘ways of coping with the fear of radiotherapy’. Sub‐themes that emerged as components of the theme ‘fears about receiving radiotherapy’ were: ‘fearing the unknown’, ‘getting burnt’, ‘damaging internal parts’ and ‘anticipating tiredness’. Patients were able to cope with their fears by trying not to worry about their fears and by seeking information. Many patients found that their fears about radiotherapy were much worse than their actual experiences of receiving treatment and the side effects they experienced.Discussion/conclusion: In discussing radiotherapy with patients, health professionals have a window of opportunity at the planning appointment, prior to the commencement of radiotherapy, to assess patients' understanding and concerns about radiotherapy, listen to their fears, address meanings they assign to radiotherapy and provide reassurance about radiotherapy and the management of side effects. Copyright © 2007 John Wiley & Sons, Ltd.
Risk and rationality in entrepreneurial processes
Authors: Miller Kent D. 
Published: November 2007

AbstractThis study begins with a historical overview of the connection between risk and rationality. It then broadens beyond this historical trajectory by taking entrepreneurship as a point of departure for understanding risk and rationality. Drawing from the research of Littlechild (1986), Buchanan and Vanberg (1991), and Sarasvathy et al. (2003), this study considers three entrepreneurial processes: opportunity recognition, opportunity discovery, and opportunity creation. Associated with each of these processes are unique conceptualizations of risk and rationality, reflected in distinct research streams. The final section of the study considers implications of the process‐contingent nature of risk and rationality, and motivates a broadening of the research agenda from entrepreneurial decision making to practices. Copyright © 2007 Strategic Management Society
The formation of opportunity beliefs: overcoming ignorance and reducing doubt
Authors: Shepherd Dean A. , McMullen Jeffery S. , Jennings P. Devereaux 
Published: November 2007

AbstractAlthough (opportunity) beliefs are becoming increasingly recognized as fundamental to understanding entrepreneurial cognition and strategic action, little is understood about the mechanisms that are responsible for the formation and evolution of these beliefs. Introducing the mechanisms of gists, matching, and updating from philosophy's and psychology's coherence theory, we propose a theoretical framework to explain how third‐person opportunity beliefs (beliefs that one has recognized an opportunity for someone with the right knowledge and motivation) are formed and how they evolve to become first‐person opportunity beliefs (beliefs that one has recognized an opportunity for himself or herself). We conclude by examining how the model contributes to literatures ranging from entrepreneurial cognition and action, to strategic myopia and organizational attention, to opportunity recognition, discovery, and creation. Copyright © 2007 Strategic Management Society.
Small worlds, infinite possibilities? How social networks affect entrepreneurial team formation and search
Authors: Aldrich Howard E. , Kim Phillip H. 
Published: November 2007

AbstractThe social network perspective has become an important analytical lens for understanding strategic actions among entrepreneurs. Social theorists offer two competing visions of networks' configurations: one of infinite opportunities for individuals to develop heterogeneous circles of affiliations and the other of constrained opportunities privileging only certain individuals. We draw on this tension to describe three models of network formation – random, small world, and truncated scale free – and apply them to entrepreneurial team formation and resource mobilization strategies undertaken by entrepreneurs. We compare and contrast two models of team formation – a rational process model and an interpersonal relations model – and identify the network contexts under which each is most applicable. Mundane entrepreneurial teams arise within localized clusters and appear unlikely to take advantage of what network theorists have called small world networks, which depend upon bridging ties between clusters. Nonetheless, there are entrepreneurial strategies through which new ventures might achieve the advantages of small world networks. To the extent that new ventures emerge in truncated scale free networks, their founders must work within a highly centralized structure, with its institutionalized standards making team formation and entrepreneurial search more instrumental than within small worlds. Copyright © 2007 Strategic Management Society.
Cancer proteomics
Authors: Chan Daniel W. , Liang Shu-Ling 
Published: November 2007

Conclusion
The future of cancer diagnostics will be based on a panel of proteomic biomarkers. They could be used to detect cancer at an early stage, to predict and to direct therapies. Enzymes and related proteins are important biological molecules, which could serve as cancer biomarkers. These biomarkers could be intact or fragments of proteins. The challenge is to be able to find and validate these potential biomarkers as clinical diagnostics. With the advances in proteomic technologies, we are closer than ever to find these “new” enzyme molecules or fragments. The translation of newly discovered biomarkers could provide an opportunity to revolutionize the era of personalized medicine.
Protein expression analysis ofChlamydia pneumoniae persistence by combined surface-enhanced laser desorption ionization time-of-flight mass spectrometry and two-dimensional polyacrylamide gel electrophoresis
Authors: Mukhopadhyay Sanghamitra , Jortani Saeed A. , Valdes Roland , Simmons Christine Q. , Sullivan Erin D. , Miller Richard D. , Summersgill James T. 
Published: November 2007

Abstract
The aim of this study was to examine the protein expression profiles of persistentChlamydia pneumoniae by two-dimensional polyacrylamide gel electrophoresis (2D PAGE) and surface-enhanced laser desorption ionization time-of-flight mass spectrometry (SELDI-TOF-MS). Although 2D PAGE is still the method of choice for separating and detecting components of complex protein mixtures, it has several distinct disadvantages; i.e., being labor-intensive and having a bias toward proteins within the dynamic range of the gel condition. Hence, SELDI-TOF-MS technology was used to complement 2D PAGE.C. pneumoniae-infected HEp2 cells were treated with or without IFN-γ, and protein expression profiles were determined at 48 h postinfection (hpi). Unfractionated monolayers were also used for protein profiling by SELDI-TOF, using two different chip surface types: weak cation exchanger and hydrophobic surface. Under IFN-γ-induced persistence,C. pneumoniae expresses an altered protein expression profile. Twenty chlamydial proteins showed differential regulatory patterns by SELDI-TOF-MS, two of which, HSP-70 cofactor, and a hypothetical protein, were identified by 2D PAGE and mass spectrometry. Two additional proteins, phosphatidylserine decarboxylase and 30S ribosomal protein S17, were exclusively identified by SELDI TOF-MS analysis, as these were not present in sufficient quantity for detection by 2D PAGE. We propose that a combination of 2D-PAGE and SELDI-TOF-MS may complement the disadvantages of each technique alone and may provide a rapid and precise screening technique.
Alternative Forms of Working-Class Organization and the Mobilization of Informal-Sector Workers in Brazil in the Era of Neoliberalism
Authors: Sandoval Salvador A.M. 
Published: November 2007

AbstractThis article examines recent changes in working-class collective actions. First it explains which were the main causes for the decline of traditional labor union militancy resulting from effects of economic stabilization, neoliberalization, and globalization on those key segments of labor movement that accounted for the backbone of union militancy as in the case of the automotive workers, bank workers, steelworkers, and civil servants of the Brazilian economy during the decade of the 1990s. Secondly, the article analyzes the emergence of alternative forms of worker contention among the urban informal sector and the rural workers through the landless workers movement, which also have been affected by the processes of neoliberalization and globalization, but unlike the workers in the formal sector, these continue to contend for worker entitlements and introduce new forms of worker organization different from the conventional union organizations upon which is based the Brazilian labor movement.
An epidemic of sporotrichosis in Rio de Janeiro, Brazil: epidemiological aspects of a series of cases
Authors: BARROS M. B. L. , SCHUBACH A. O. , SCHUBACH T. M. P. , WANKE B. , LAMBERT-PASSOS S. R. 
Published: November 2007

SUMMARYThe first epidemic of sporotrichosis in humans as a result of zoonotic transmission was identified in Rio de Janeiro, Brazil, in 1998. A cross-sectional study was conducted applying questionnaires to patients seen in 2002 at Evandro Chagas Clinical Research Institute, Fiocruz, with a confirmed diagnosis of sporotrichsosis. A total of 73 dwellings were studied, where 255 individuals, including 94 patients and 161 healthy household contacts, lived with 133 cats with sporotrichosis. Most dwellings were houses with 83% having complete basic sanitation. Among patients, there was a predominance of women with a median age of 41 years who were engaged in domestic activities. These women contracted the disease twice more often than men. The prevalence of sporotrichosis was four times higher among patients caring for animals, irrespective of gender. In the current epidemic of sporotrichosis, taking care of sick cats was the main factor associated with transmission of the disease to humans.
Low prevalence of HIV and other selected sexually transmitted infections in 2004 in pregnant women from Kinshasa, the Democratic Republic of the Congo
Authors: KINOSHITA-MOLEKA R. , SMITH J. S. , ATIBU J. , TSHEFU A. , HEMINGWAY-FODAY J. , HOBBS M. , BARTZ J. , KOCH M. A. , RIMOIN A. W. , RYDER R. W. 
Published: November 2007

SUMMARYThis study examined the prevalence of HIV and other sexually transmitted infections (STIs) in pregnant women in Kinshasa, the Democratic Republic of the Congo (DRC). Between April and July 2004, antenatal attendees at two of the largest maternity clinics in Kinshasa were tested to identify HIV status, syphilis, Chlamydia trachomatis (CT) and Neisseria gonorrhoeae (NG). HIV seroprevalence was 1·9% in 2082 women. With PCR techniques, CT and NG infections were also uncommon in the first 529 women (1·7% and 0·4%, respectively). No active syphilis infection case was identified by Treponema pallidum haemagglutination assay (TPHA) and rapid plasma reagin test (RPR). A woman's risk of HIV infection was significantly associated with her reporting a male partner having had other female sexual partners (OR 2·7, 95% CI 1·2–6·2). The continuing low seroprevalence of HIV in pregnant women from Kinshasa was confirmed. Understanding factors associated with this phenomenon could help prevent a future HIV epidemic in low HIV transmission areas in Africa.
Changes in volume of drinking after changes in alcohol taxes and travellers' allowances: results from a panel study
Authors: Mäkelä Pia , Bloomfield Kim , Gustafsson Nina‐Katri , Huhtanen Petri , Room Robin 
Published: November 2007

ABSTRACTAims The aim of this paper is to study short‐term changes in alcohol consumption by subgroups of the population in Denmark, Finland and southern Sweden following large‐scale decreases in alcohol taxation in Denmark and Finland and large increases in travellers' allowances in Finland and Sweden.Design General population random samples surveyed before and after the changes, using northern Sweden as a control site.Setting Denmark, Finland, southern Sweden and northern Sweden.Participants Respondents aged 16–69 years.Measurements Volume of drinking is the main measure reported. Changes are examined by gender, age, income and year 2003 consumption level.Results Consumption decreased or remained the same among women and men in all three study sites. Relative changes were similar across subgroups of age, gender and income in all countries. In absolute terms, there was a consistent differential change by age in Denmark, Finland and Southern Sweden, with the higher level of the young and lower level of the old converging. Women's and men's consumption converged in Finland and southern Sweden. The changes did not differ systematically by income. Changes were not larger among heavier drinkers.Conclusions The results did not confirm expectations: an increase in consumption larger than that in the control site could not be shown in any of the countries or subgroups of the population. If there has been an effect – as shown in aggregate data in Finland – it seems to have been stronger among the old than the young and, in Finland and southern Sweden, among women rather than men.
Effects of progression to cigarette smoking on depressed mood in adolescents: evidence from the National Longitudinal Study of Adolescent Health
Authors: Munafò Marcus R. , Hitsman Brian , Rende Richard , Metcalfe Chris , Niaura Raymond 
Published: November 2007

ABSTRACTAims  To investigate the relationship between smoking status and continuously distributed depressed mood among a cohort of adolescents.Design  Quasi‐experimental design, selecting the subset of adolescents who reported never having smoked a cigarette at baseline, some of whom progressed subsequently to smoking at follow‐up approximately 1 year later.Setting  Data were drawn from the National Longitudinal Study of Adolescent Health, an ongoing study designed to assess the health status of adolescents, and explore the causes of adolescent health‐related behaviours.Participants  Nationally representative sample of adolescents from the USA (n = 12 149), including a subsample who reported never having smoked a cigarette at baseline (n = 5475), aged on average 15 years at baseline and of predominantly European ancestry.Measurements  Logistic and linear regression models controlling for potential confounders to explore the relationship between smoking status and depressed mood measured using the Centers for Epidemiological Studies Depression Scale (CES‐D).Findings  Various relationships between smoking status and depressed mood were observed, with a general trend for these effects to be greater among females. Smoking status at baseline did not significantly predict CES‐D score at follow‐up, although this effect approached significance in females (P = 0.077). Among never smokers at baseline, level of depressed mood at baseline predicted subsequent progression to smoking initiation (P = 0.022) but not progression to regular smoking (P = 0.229). Among never smokers at baseline, progression to smoking initiation during the follow‐up period was associated with higher CES‐D scores at follow‐up, even after adjusting for baseline depressed mood (P < 0.001), with this effect greater for females than for males. Among those who initiated smoking, progression to regular smoking was associated with higher CES‐D score at follow‐up among females (P = 0.001), but not males (P = 0.966).Conclusions  These data appear to support a complex model of the relationship between depressed mood and smoking status which includes elements of both confounding and causal models. The relationship between cigarette smoking and depression may be a factor in the development of subsequent dependence.