bluuebunny/crossref_metadata_2025_split huggingface dataset:
Synthesis, characterization, and star polymer assembly of boronic acid end‐functionalized polycaprolactone
Authors: Korich Andrew L. , Walker Amanda R. , Hincke Christopher , Stevens Caitlin , Iovine Peter M. 
Published: November 2010

AbstractBoronic acid end‐functionalized polycaprolactone (PCL) polymers were synthesized by ring‐opening polymerization using a pinacol boronate ester‐containing (Bpin) initiator. The polymerization provides access to boron‐terminated polymers (i.e. Bpin‐PCL‐OH) with narrow molecular weight distributions (PDI = 1.09). Postsynthetic manipulation of the polymer's terminal hydroxyl group by copper‐catalyzed azide‐alkyne cycloaddition chemistry provides a series of bis end‐functionalized polymers with significant structural diversity at the termini. Deprotection of the boronate ester end group was accomplished with an acidic solid phase DOWEX resin. The boronate ester deprotection methodology does not result in hydrolysis of the polymeric backbone. The boronic acid‐tipped polymers were converted into star polymer assemblies using thermal dehydration and ligand‐facilitated trimerization. Thermal dehydration of (HO)2B‐PCL‐OAc to the corresponding boroxine‐based star polymer assembly was inefficient and lead to degradation products. Ligand‐facilitated trimerization using either pyridine or 7‐azaindole as the Lewis base was efficient and mild. © 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2010
Solid‐state thermal stability and degradation of a family of poly(N‐isopropylacrylamide‐co‐hydroxymethylacrylamide) copolymers
Authors: Saeed Abdirahman , Georget Dominique M. R. , Mayes Andrew G. 
Published: November 2010

AbstractThere is widespread interest in responsive polymers that show cloud point behavior, but little attention is paid to their solid state thermal properties. To manufacture products based on such polymers, it may be necessary to subject them to high temperatures; hence, it is important to investigate their thermal behavior. In this study, we characterized a family of poly(N‐isopropylacrylamide‐co‐hydroxymethylacrylamide) copolymers. Although poly(N‐isopropylacrylamide) shows very high thermal stability (up to 360 °C), introduction of hydroxy side chains leads to a significant reduction in stability and new degradation processes become apparent. Thermogravimetric analysis and fourier transform infrared spectroscopy (FT‐IR) indicate that the first degradation process involves a chemical dehydration step (110–240 °C), supported by the nonreversing heat flow response in modulated temperature differential scanning calorimetry. Water loss scales with the fraction of hydroxy monomer in the copolymer. Glass transition temperatures (Tg) are higher than the temperatures causing dehydration; hence, these values relate to newly‐formed copolymer structures produced by controlled heating under nitrogen. Fourier transform‐Raman (FT‐Raman) spectra suggest that this transition involves imine formation. The Tg increases as the fraction of hydroxy groups in the original copolymer increases. Further heating leads to degradation and mass loss, and more complex changes in the FT‐IR spectra, consistent with formation of unsaturated species. © 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2010
Size and morphology controllable core cross‐linked self‐aggregates from poly(ethylene glycol‐b‐succinimide) copolymers
Authors: Park Chan Woo , Lee Hyun Jin , Yang Hee‐man , Woo Min‐ah , Park Hyun gyu , Kim Jong‐Duk 
Published: November 2010

AbstractWe developed a simple route to prepare stabilized micelles and nanovesicles in aqueous solutions. A hydrophobic poly(succinimide) (PSI) was conjugated with the hydrophilic poly(ethylene glycol) (PEG) as a new type of cross‐linkable unit. Spherical aggregates were formed when dissolving the amphiphilic PEG682‐b‐PSI130 copolymer in aqueous solutions directly, and polymer nanovesicles were prepared by a precipitation‐dialysis method using PEG455‐b‐PSI130 copolymer. Bifunctional primary amine was added to the micelle or nanovesicle solutions to prepare cross‐linked structures via aminolysis reaction of the succinimide units. The degree of cross‐linking was controlled by adjusting the molar ratio of the cross‐linker to the succinimide units. Increasing the degree of cross‐linking leads to the compaction of the micelle core thus reduced diameter. The cross‐linked polymer micelles or nanovesicles maintained their morphology in extremely diluted solutions because of their structural stability. © 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2010
Another look at the degree‐Kirchhoff index
Authors: Palacios José Luis , Renom José Miguel 
Published: November 2010

AbstractLet G be an arbitrary graph with vertex set {1,2, …,N} and degrees di ≤ D, for fixed D and all i, then for the index R′(G) = ∑i < jdidjRij we show that

We also show that the minimum of R′(G) over all N‐vertex graphs is attained for the star graph and its value is 2N2 − 5N + 3. © 2010 Wiley Periodicals, Inc. Int J Quantum Chem, 2011
Electronic structure, chemical bonding, and oxidation numbers of first‐row transition metals in [MePIm2] complexes and their cations
Authors: Mitin Alexander V. , Kubicki James D. , Merz Kenneth M. 
Published: November 2010

AbstractThe qualitative structures of the upper one‐electron energy levels of imidazole‐coordinated first‐row transition metal porphyrin [MePIm2] complexes established in the present study have shown that the second oxidation number of the first‐row transition metals in the neutral complexes do not change in their cations and double cations. It was found that occupied orbitals of the density functional theory method obtained with B3LYP functional are not correctly ordered. Therefore, they cannot be used in investigations of the orbital structure of the upper molecular orbitals. A qualitative analysis of density functional theory method wave functions in terms of Mulliken and natural charges of atoms, together with an analysis of electrostatic potentials of the neutral [MePIm2] complex, its single and double cations, demonstrates that the highest occupied orbitals of these complexes are mainly formed by atomic orbitals of the porphyrin ring atoms. Therefore, transition metal atoms are not active in chemical reactions with these complexes unless the 3d electrons of transition metal atoms are excited, for example by light. A mechanism of an electron transfer reaction that occurs between a heme cytochrome and Fe‐oxide mineral surface is discussed in the light of the obtained results. © 2010 Wiley Periodicals, Inc. Int J Quantum Chem, 2011
Classification of Turkish Extra Virgin Olive Oils by a SAW Detector Electronic Nose
Authors: Kadiroğlu Pınar , Korel Figen , Tokatlı Figen 
Published: November 2010

AbstractAn electronic nose (e‐nose), in combination with chemometrics, has been used to classify the cultivar, harvest year, and geographical origin of economically important Turkish extra virgin olive oils. The aroma fingerprints of the eight different olive oil samples [Memecik (M), Erkence (E), Gemlik (G), Ayvalık (A), Domat (D), Nizip (N), Gemlik–Edremit (GE), Ayvalık–Edremit (AE)] were obtained using an e‐nose consisting a surface acoustic wave detector. Data were analyzed by principal component analysis (PCA) and discriminant function analysis (DFA). Classification of cultivars using PCA revealed that A class model was correctly discriminated from N in two harvest years. The DFA classified 100 and 97% of the samples correctly according to the cultivar in the 1st and 2nd harvest years, respectively. Successful separation among the harvest years and geographical origins were obtained. Sensory analyses were performed for determining the differences in the geographical origin of the olive oils and the preferences of the panelists. The panelists could not detect the differences among olive oils from two different regions. The cultivar, harvest year, and geographical origin of extra virgin olive oils could be discriminated successfully by the e‐nose.
Cryptorchidie: influence sur la fertilité de l’âge au moment de l’orchidopexie, du siège et de la taille du testicule et de l’existence d’anomalies épididymaires
Authors: Jallouli M. , Mefteh S. , Rebai T. , Mhiri R. 
Published: November 2010

RésuméMalgré le traitement chirurgical, la cryptorchidie reste la cause la plus fréquente de stérilité. À travers une revue de la littérature, les auteurs relatent les données actuelles concernant l’influence de l’âge au moment de l’orchidopexie, de la taille du testicule, du siège du testicule et de l’existence d’une indépendance épididymotesticulaire sur la fertilité ultérieure.
The quality of life and health utility burden of recurrent respiratory papillomatosis in children
Authors: Chadha Neil K. , Allegro Jennifer , Barton Michelle , Hawkes Michael , Harlock Hayley , Campisi Paolo 
Published: November 2010

OBJECTIVEIn this study we 1) measured the impact of juvenile‐onset recurrent respiratory papillomatosis on health‐related quality of life, voice‐related quality of life, and family psychosocial well‐being; and 2) compared these different measures, exploring their intercorrelation and their correlation with clinical disease severity.STUDY DESIGNCross‐sectional qualitative study.SETTINGTertiary academic pediatric hospital.SUBJECTS AND METHODSTwenty consecutive children with active juvenile‐onset recurrent respiratory papillomatosis (JoRRP) were included. Standardized interviews were performed on parents and children with the use of four validated tools: the Health Utilities Index version 3; the Pediatric Voice‐Related Quality of Life survey; the Impact on Family Scale; and a visual analogue health preference measure. Clinical disease severity and demographic data also were collected.RESULTSSubjects (13 male, 7 female) had a median age of 9.2 years, median age of JoRRP onset of 3.8 years, and averaged four procedures per year of disease. Mean health utility was 0.76 (95% confidence interval 0.68–0.84) on a scale of 0 (death) to 1 (perfect health). Marked impact on voice‐related quality of life and family psychosocial health also was identified. Health burden correlated poorly with existing methods of severity scoring.CONCLUSIONThis is the first study to use validated measures of health utility, voice‐related quality of life, and psychosocial impact. This information has public health implications, providing essential parameters for accurate modeling studies and cost‐utility analysis of future interventions, including different human papilloma virus vaccination strategies.
Induced endolymphatic flow from the endolymphatic sac to the cochlea in Ménière's disease
Authors: Mandalà Marco , Colletti Liliana , Carner Marco , Cerini Roberto , Barillari Marco , Mucelli Roberto Pozzi , Colletti Vittorio 
Published: November 2010

OBJECTIVEThe aim of the present study was to verify whether drugs injected into the endolymphatic sac (ES) can reach the cochlea and possibly treat inner ear disorders.STUDY DESIGNProspective cohort study.SETTINGTertiary referral center, Otolaryngology Department, University of Verona.SUBJECTS AND METHODSPatients with Ménière's disease (MD) who were candidates for ES decompression were selected. Nineteen subjects received dexamethasone (DEX) via injection into the ES. To objectively define whether substances administered into the ES could reach the cochlea, we added gadolinium (GD) in three patients. All subjects had intraoperative electrocorticogram recordings and an audiologic follow‐up. The three subjects who underwent injection of the DEX‐GD solution were followed‐up with magnetic resonance imaging. The audio‐logical data are presented during a follow‐up period of 12 months.RESULTSIntraoperative electrocochleography recordings revealed no changes in two patients and summating potentials and compound action potential latency and wave‐form modifications in all the other subjects. GD distribution was observed from 48 hours to one week after ES injection into the cochlea of the three subjects injected with DEX‐GD. GD‐related enhancement of inner ear structures lasted more than two weeks in all subjects. Pure tone average results showed hearing improvement of at least 20 dB HL in 42 percent of patients (8 of 19) at the 12‐month follow‐up. Statistically significant differences emerged between the mean pure tone average of the ES procedure subjects at one and 12 months after surgery (P = 0.0096).CONCLUSIONThis novel approach might reveal new prospects for treating viral, metabolic, autoimmune, and genetic disorders of the cochlea.
A speleothem record of Holocene climate variability from southwestern Mexico
Authors: Bernal Juan Pablo , Lachniet Matthew , McCulloch Malcolm , Mortimer Graham , Morales Pedro , Cienfuegos Edith 
Published: November 2010

AbstractA paleoclimate reconstruction for the Holocene based upon variations of δ18O in a U–Th dated stalagmite from southwestern Mexico is presented. Our results indicate that the arrival of moisture to the area has been strongly linked to the input of glacial meltwaters into the North Atlantic throughout the Holocene. The record also suggests a complex interplay between Caribbean and Pacific moisture sources, modulated by the North Atlantic SST and the position of the ITCZ, where Pacific moisture becomes increasingly more influential through ENSO since ~ 4.3 ka. The interruption of stalagmite growth during the largest climatic anomalies of the Holocene (10.3 and 8.2 ka) is evidenced by the presence of hiatuses, which suggest a severe disruption in the arrival of moisture to the area. The δ18O record presented here has important implications for understanding the evolution of the North American Monsoon and climate in southwestern Mexico, as it represents one of the most detailed archives of climate variability for the area spanning most of the Holocene.
Youth music and politics in post-war Sierra Leone
Authors: Shepler Susan 
Published: November 2010

ABSTRACTThe brutal, eleven-year long civil war in Sierra Leone has been understood by many scholarly observers as ‘a crisis of youth’. The national elections of 2007 were notable for an explosion of popular music by young people directly addressing some of the central issues of the election: corruption of the ruling party and lack of opportunities for youth advancement. Though produced by youth and understood locally as youth music, the sounds were inescapable in public transport, markets, and parties. The musical style is a combination of local idioms and West African hip-hop. The lyrics present a young people's moral universe in stark contrast to that of their elders. This paper addresses the themes of these election-focused songs as well as the emerging subaltern youth identity discernible in supposedly less political songs.
Turkey's opening to Africa
Authors: Özkan Mehmet , Akgün Birol 
Published: November 2010

ABSTRACTAs part of on-going multidimensional foreign policy changes in recent years, there has been since 1998 a revival in Turkey's relations with Africa. Initially rather passive, after 2005 this became a massive effort to develop relations with the whole continent. However, Turkey's Africa policy is unique in Turkish foreign policy, since for the first time it is driven and complemented by the activities of civil society organisations in and about Africa. Conceptualisation of Africa in Turkish society has changed dramatically in less than a decade, and the recent Turkey–Africa Cooperation Summit should be seen as part of this trend. Turkey's opening to Africa is not a short-term inclination, but is likely to develop and deepen in coming years.
Composition, uniqueness and variability of the epiphytic bacterial community of the green alga Ulva australis
Authors: Burke Catherine , Thomas Torsten , Lewis Matt , Steinberg Peter , Kjelleberg Staffan 
Published: November 2010

Abstract
Green Ulvacean marine macroalgae are distributed worldwide in coastal tidal and subtidal ecosystems. As for many living surfaces in the marine environment, little is known concerning the epiphytic bacterial biofilm communities that inhabit algal surfaces. This study reports on the largest published libraries of near full-length 16S rRNA genes from a marine algal surface (5293 sequences from six samples) allowing for an in-depth assessment of the diversity and phylogenetic profile of the bacterial community on a green Ulvacean alga. Large 16S rRNA gene libraries of surrounding seawater were also used to determine the uniqueness of this bacterial community. The surface of Ulva australis is dominated by sequences of Alphaproteobacteria and the Bacteroidetes, especially within the Rhodobacteriaceae, Sphingomonadaceae, Flavobacteriaceae and Sapropiraceae families. Seawater libraries were also dominated by Alphaproteobacteria and Bacteroidetes sequences, but were shown to be clearly distinct from U. australis libraries through the clustering of sequences into operational taxonomic units and Bray–Curtis similarity analysis. Almost no similarity was observed between these two environments at the species level, and only minor similarity was observed at levels of sequence clustering representing clades of bacteria within family and genus taxonomic groups. Variability between libraries of U. australis was relatively high, and a consistent sub-population of bacterial species was not detected. The competitive lottery model, originally derived to explain diversity in coral reef fishes, may explain the pattern of colonization of this algal surface.
The influence of physical activity level on heart rate variability among asthmatic adults
Authors: Tsai Yueh‐Shia , Lai Fu‐Chih , Chen Su‐Ru , Jeng Chii 
Published: November 2010

Aims.  The aim of the study was to evaluate the impact of physical activity levels on heart rate variability among asthmatic patients.Background.  In recent years, heart rate variability is frequently used to assess the autonomic nervous system. The pathogenesis of asthma is probably related to autonomic dysfunction. Adequate exercise is considered beneficial to patients who suffer from asthma. However, the relationship between physical activity and the autonomic nervous system of adult asthmatic patients is still unknown.Design.  A cross‐sectional survey.Methods.  A total of 54 subjects (27 healthy persons and 27 asthmatic patients matched by age and gender) were recruited for this study. Heart rate variability was determined by frequency analysis and measured in both resting and active states. The Seven‐Day Physical Activity Recall was used to determine the subject’s amount of weekly activity.Results.  The results showed that the total power, low frequency (ms2), low frequency (nu) and low frequency/high frequency (nu) but not high frequency (nu) were significantly higher in healthy adults compared to asthmatic patients, no matter whether resting or exercising. In both groups, the greater the amount of moderate‐to‐vigorous physical activity, the higher the TP observed. However, a positive relationship between the amount of moderate‐to‐vigorous physical activity and low frequency (nu) and a negative relationship with high frequency (nu), respectively, was demonstrated only in asthmatic patients. There was no significant difference in heart rate variability between the asthmatic patients who engaged in more moderate‐to‐vigorous physical activity and the healthy patients.Conclusions.  Although the asthmatic patients had poor heart rate variability compared with healthy people, engaging in higher amounts of moderate‐to‐vigorous physical activity may result in a heart rate variability similar to that of healthy people.Relevance to clinical practice.  The results of this study suggest that healthcare professionals should encourage asthmatic patients to take as much physical exercise as they can in their daily lives.
Genetic analyses reveal hybridization but no hybrid swarm in one of the world’s rarest birds
Authors: STEEVES TAMMY E. , MALONEY RICHARD F. , HALE MARIE L. , TYLIANAKIS JASON M. , GEMMELL NEIL J. 
Published: November 2010

AbstractHybridization facilitated by human activities has dramatically altered the evolutionary trajectories of threatened taxa around the globe. Whereas introduced mammalian predators and widespread habitat loss and degradation clearly imperil the recovery and survival of the New Zealand endemic black stilt or kakī (Himantopus novaezelandiae), the risk associated with hybridization between this critically endangered endemic and its self‐introduced congener, the pied stilt or poaka (Himantopus himantopus leucocephalus) is less clear. Here, we combine Bayesian admixture analyses of microsatellite data with mitochondrial DNA sequence data to assess the levels of hybridization and introgression between kakī and poaka. We show that birds classified as hybrids on the basis of adult plumage are indeed of hybrid origin and that hybridization between kakī and poaka is both extensive and bidirectional. Despite this, we found almost no evidence for introgression from poaka to kakī, thus negating the popular belief that kakī represent a hybrid swarm. To our knowledge, ours represents the first comprehensive study to document a lack of widespread introgression for a species at risk despite a recent history of extensive bidirectional human‐induced hybridization. We attribute this rather surprising result, in part, to reduced reproductive success in female hybrids combined with a transient male‐biased kakī sex ratio. To maximize the evolutionary potential of kakī, we use these data to recommend conservation management activities aimed to maintain the genetic integrity and to maximize the genetic diversity of this iconic rare bird.
Phylogenetics of Acrocirridae and Flabelligeridae (Cirratuliformia, Annelida)
Authors: Osborn Karen J. , Rouse Greg W. 
Published: November 2010

Osborn, K. J. & Rouse, G. W. (2010). Phylogenetics of Acrocirridae and Flabelligeridae (Cirratuliformia, Annelida). —Zoologica Scripta, 40, 204–219.When seven deep‐sea, swimming cirratuliforms were recently discovered, the need for a thorough phylogenetic hypothesis for Cirratuliformia was clear. Here, we provide a robust phylogenetic hypothesis for the relationships within Acrocirridae and increase the taxon sampling and resolution within Flabelligeridae based on both molecular (18S, 28S, 16S, COI and CytB) and morphological data. Data partitions were analyzed separately and in combination. Acrocirridae and Flabelligeridae were reciprocally monophyletic sister groups when rooted by cirratulids. The seven recently discovered species form a clade within Acrocirridae and will be designated as four genera based on phylogenetic relationships and apomorphies. A revised diagnosis is provided for Swima, restricting the genus to three species distinguished by a thick gelatinous sheath, transparent body, simple nuchal organs, a single medial subulate branchia, and four pair of small segmental branchiae modified as elliptical, bioluminescent sacs. Helmetophorus and Chauvinelia are maintained as separate genera based on morphological differences. Evidence for flabelligerid branchiae being segmental is provided, the papillae on segment two of most acrocirrids is confirmed to be the nephridiopores, and scanning electron microscopy is used to examine acrocirrid spinous chaetae in comparison with flabelligerid segmented chaetae.