bluuebunny/crossref_metadata_2025_split huggingface dataset:
Aminocatalytic Cross‐Coupling Approach via Iminium Ions to Different CC Bonds
Authors: Mupparapu Nagaraju , Battini Narsaiah , Battula Satyanarayana , Khan Shahnawaz , Vishwakarma Ram A. , Ahmed Qazi Naveed 
Published: December 2014

AbstractGiven the attractive ability of iminium ions to functionalize molecules directly at ostensibly unreactive positions, the reactivity of iminium ions, in which an α CH2 group is replaced by CO was explored. Background studies on the ability of such iminium cations to promote reactions via an iminium‐catalyzed or iminium‐equivalent pathway are apparently unavailable. Previously, tandem cross‐coupling reactions were reported, in which an iminium ion undergoes nucleophilic 1,2‐addition to give a putative three‐component intermediate that abstracts a proton in situ and undergoes self‐deamination followed by unprecedented DMSO/aerobic oxidation to generate α‐ketoamides. However, later it was observed that iminium ions can generate valuable α‐ketoamides through simple aerobic oxidation. In all reactions, iminium ions were generated in situ by reaction of 2‐oxoaldehydes with secondary amines.
What Controls the Magnetic Exchange Interaction in Mixed‐ and Homo‐Valent Mn7 Disc‐Like Clusters? A Theoretical Perspective
Authors: Vignesh Kuduva R. , Langley Stuart K. , Murray Keith S. , Rajaraman Gopalan 
Published: December 2014

AbstractDensity functional theory (DFT) studies have been undertaken to compute the magnetic exchange and to probe the origin of the magnetic interactions in two hetero‐ and two homo‐valent heptanuclear manganese disc‐like clusters, of formula [MnII4MnIV3(tea)(teaH2)3(peolH)4] (1), [MnII4MnIII3F3(tea)(teaH)(teaH2)2(piv)4(Hpiv)(chp)3] (2), [MnII7(pppd)6(tea)(OH)3] (3) and [MnII7 (paa)6(OMe)6] (4) (teaH3=triethanolamine, peolH4=pentaerythritol, Hpiv=pivalic acid, Hchp=6‐chloro‐2‐hydroxypyridine, pppd=1‐phenyl‐3‐(2‐pyridyl) propane‐1,3‐dione; paaH=N‐(2‐pyridinyl)acetoacetamide). DFT calculations yield J values, which reproduce the magnetic susceptibility data very well for all four complexes; these studies are also highlighting the likely ageing/stability problems in two of the complexes. It is found that the spin ground states, S, for complexes 1–4 are drastically different, varying from S=29/2 to S=1/2. These values are found to be controlled by the nature of the oxidation state of the metal ions and minor differences present in the structures. Extensive magneto–structural correlations are developed for the seven building unit dimers present in the complexes, with the correlations unlocking the reasons behind the differences in the magnetic properties observed. Independent of the oxidation state of the metal ions, the Mn‐O‐Mn/Mn‐F‐Mn angles are found to be the key parameters, which significantly influence the sign as well as the magnitude of the J values. The magneto–structural correlations developed here, have broad applicability and can be utilised to understand the magnetic properties of other Mn clusters.
Amphiphilic Polyoxometalates for the Controlled Synthesis of Hybrid Polystyrene Particles with Surface Reactivity
Authors: Lesage de La Haye Jennifer , Guigner Jean‐Michel , Marceau Eric , Ruhlmann Laurent , Hasenknopf Bernold , Lacôte Emmanuel , Rieger Jutta 
Published: December 2014

AbstractAmphiphilic organo‐polyoxometalates (POMs) used in the radical emulsion polymerization of styrene allowed the preparation in aqueous medium of stable 50–100 nm polystyrene–POM composite latexes. Thanks to the presence of a trithiocarbonate group in the POM amphiphile, POMs could be covalently linked to the polymer particle surface. The chemical and catalytic integrity of the POMs was confirmed, and the POM‐mediated surface photoactivity of the latexes was demonstrated by the spatially controlled nucleation of silver nanoparticles at the periphery of the composites.
Peptoid‐Ligated Pentadecanuclear Yttrium and Dysprosium Hydroxy Clusters
Authors: Thielemann Dominique T. , Wagner Anna T. , Lan Yanhua , Oña‐Burgos Pascual , Fernández Ignacio , Rösch Esther S. , Kölmel Dominik K. , Powell Annie K. , Bräse Stefan , Roesky Peter W. 
Published: December 2014

AbstractInvited for the cover of this issue are the groups of Yanhua Lan, Peter W. Roesky, and Stefan Bräse at the Karlsruhe Institute of Technology, and Ignacio Fernández at the University of Almería. The image depicts seals on a North Sea beach. Seals are known to be very skilled at balancing and other tricks, whereas our skills include crystallizing new compounds and further examining their properties. Read the full text of the article at 10.1002/chem.201405569.
Probing o‐Diphenylphosphanyl Benzoate (o‐DPPB)‐Directed CC Bond Formation: Total Synthesis of Dictyostatin
Authors: Wünsch Sebastian , Breit Bernhard 
Published: December 2014

AbstractHerein, we report a robust total synthesis of dictyostatin. This polyketide natural product has attracted much attention because of its impressive antiproliferative activity against several human cancer‐cell lines. We accomplished its synthesis in a highly convergent manner from three fragments of equal complexity, which were prepared on multigram scale. The southern and northwestern subunits were constructed through application of our o‐DPPB‐directed hydroformylation and allylic substitution methodology, respectively. These methods generated the C6 and C14 stereocenters of dictyostatin with good diastereoselectivities and simultaneously allowed further elaboration of the fragments by Wittig olefination and Sharpless asymmetric epoxidation, respectively. The compelling performance of the hydroformylation and allylic substitution with regard to practicability, selectivity, and scale underline their value for the construction of propionate motifs.
Culture, leadership and motivation in two Commonwealth Caribbean countries: One look at the African Diaspora
Authors: Holder Khaleid , Knight Nicole , Punnett Betty Jane , Charles Reccia 
Published: December 2014

AbstractLittle is known of Caribbean people's views on their culture or of their beliefs regarding leadership and motivation. This study reports the results of a Delphi Technique with people in leadership positions and focus groups. Across groups, responses were relatively consistent: ethnicity and culture are described as influenced by religion, and Christianity in particular; African roots and country of origin are important; effective leaders are charismatic, visionary, results oriented, and they motivate others, lead by example, and develop vision and goals. Leaders believe motivation comes from making a difference for others. Nonleaders believe leaders are influenced by financial rewards and self‐fulfilment; nonleaders are motivated primarily by financial rewards. The results are generally similar to Western beliefs, but some interesting differences are identified. Copyright © 2014 ASAC. Published by John Wiley & Sons, Ltd.
Local adaptations in bryophytes revisited: the genetic structure of the calcium‐tolerant peatmoss Sphagnum warnstorfii along geographic and pH gradients
Authors: Mikulášková Eva , Hájek Michal , Veleba Adam , Johnson Matthew G. , Hájek Tomáš , Shaw Jonathan A. 
Published: December 2014

AbstractBryophytes dominate some ecosystems despite their extraordinary sensitivity to habitat quality. Nevertheless, some species behave differently across various regions. The existence of local adaptations is questioned by a high dispersal ability, which is thought to redistribute genetic variability among populations. Although Sphagnum warnstorfii is an important ecosystem engineer in fen peatlands, the causes of its rather wide niche along the pH/calcium gradient are poorly understood. Here, we studied the genetic variability of its global populations, with a detailed focus on the wide pH/calcium gradient in Central Europe. Principal coordinates analysis of 12 polymorphic microsatellite loci revealed a significant gradient coinciding with water pH, but independent of geography; even samples from the same fens were clearly separated along this gradient. However, most of the genetic variations remained unexplained, possibly because of the introgression from phylogenetically allied species. This explanation is supported by the small heterogeneous cluster of samples that appeared when populations morphologically transitional to S. subnites, S. rubellum, or S. russowii were included into the analysis. Alternatively, this unexplained variation might be attributed to a legacy of glacial refugia with recently dissolved ecological and biogeographic consequences. Isolation by distance appeared at the smallest scale only (up to 43 km). Negative spatial correlations occurred more frequently, mainly at long distances (up to 950 km), implying a genetic similarity among samples which are very distant geographically. Our results confirm the high dispersal ability of peatmosses, but simultaneously suggested that their ability to cope with a high pH/calcium level is at least partially determined genetically, perhaps via specific physiological mechanisms or a hummock‐forming ability.
Inhibition of Alkali–Silica Reaction in Hollow Porcelain Insulator
Authors: Shinka Hiroyuki , Yamamoto Takeshi , Komatsu Hiroaki , Hongakiuchi Takeshi 
Published: December 2014

SUMMARYHollow porcelain insulators are widely used in gas‐insulated power apparatus and oil‐filled power apparatus. Previously, it was thought that hollow porcelain insulators are not subject to aging deterioration. However, gas and oil leaks caused by the alkali–silica reaction in the porcelain where it is in contact with cementing parts have been reported in recent years. We experimentally verified the generation process of the alkali–silica reaction by using a hollow porcelain insulator removed from the substation, and examined an inhibition method of alkali–silica reaction based on the use of lithium nitrite. It was found that the alkali–silica reaction occurs in the hollow porcelain insulator and that lithium nitrite is effective for inhibition of the alkali–silica reaction.
Structural Variation in [PdX2{RE(CH2)nNMe2}] (E = Se, Te; X = Cl, OAc) Complexes: Experimental Results, Computational Analysis, and Catalytic Activity in Suzuki Coupling Reactions
Authors: Paluru Dilip K. , Dey Sandip , Wadawale Amey , Maity Dilip K. , Bhuvanesh Nattamai , Jain Vimal K. 
Published: December 2014

AbstractA series of chalcogenoether ligands RE(CH2)nNMe2 (1) [E = Se or Te; R = Ph, o‐tol (o‐tol = ortho‐tolyl), Mes (Mes = 2,4,6‐trimethylphenyl); n = 2 or 3] and their palladium complexes [PdX2{RE(CH2)nNMe2}]m [X = Cl (2) or OAc (3); m = 1, 2] were synthesized. Complexes [PdCl2(RECH2CH2NMe2)] [R/E = Ph/Se (2a), Mes/Se (2b), Mes/Te (2c)] were isolated as monomers. Complexes [PdCl2(RECH2CH2CH2NMe2)]m [R/E = Ph/Se (2d), Ph/Te (2e), o‐tol/Te (2f)] exist in one monomeric and two dimeric forms in solution; their ratio depends on E and R as revealed by NMR spectroscopic data. Crystal structures of monomeric 2a, 2b, 3b, 2d, 2f, and dimeric 2e were established. Compounds 2a, 2d, 2e, and 2f were also investigated by means of density functional theory (DFT)‐based quantum chemical calculations to understand structural variation. The complexes that contained acetate or chalcogenoether ligands with n = 3 showed higher catalytic activity than other derivatives in Suzuki C–C cross‐coupling reactions.
Oleaginous yeast Cryptococcus curvatus exhibits interplay between biosynthesis of intracellular sugars and lipids
Authors: Tchakouteu Sidoine Sadjeu , Chatzifragkou Afroditi , Kalantzi Ourania , Koutinas Apostolis A. , Aggelis George , Papanikolaou Seraphim 
Published: December 2014

AbstractPatterns of the biosynthesis of major metabolites of the oleaginous yeast Cryptococcus curvatus NRRL Y‐1511 were investigated during cultivation on sugar‐based media. When lactose or sucrose was employed as substrate under nitrogen‐limited conditions, the yeast strain accumulated high quantities of intra‐cellular total sugars (ITS) at the beginning of fermentation (up to 68% w/w), with ITS values progressively decreasing to 20%, w/w, at the end of the fermentation. Decrease in ITS content and consumption of extra‐cellular lactose led to a subsequent rise in lipid accumulation, reaching 29.8% in dry cell weight at 80 g/L of initial lactose concentration. Lactose was a more favorable substrate for lipid production than sucrose. In nitrogen‐excess conditions, ITS were produced in significant quantities despite the continuous presence of nitrogen in the medium. Growth on lactose was not followed by secretion of extra‐cellular β‐galactosidase. High quantities of extra‐cellular invertase were observed during growth on sucrose. The composition of ITS was highly influenced by the sugar used as substrate. Cellular lipids contained mainly palmitic and to lesser extent linoleic and stearic acids. This is the first report in the literature that demonstrates the interplay between the biosynthesis of intra‐cellular total sugars and lipid synthesis for oleaginous yeast strains.Practical applications: Cryptococcus curvatus represents a promising candidate for the successful production of microbial lipids and polysaccharides during growth on several types of low‐cost sugars utilized as substrates. Thus, C. curvatus could be used to produce a variety of metabolites useful for industrial biotechnology.Interplay between the biosynthesis of intra‐cellular total sugars produced per unit of dry weight (YITS/X %, w/w) and intra‐cellular lipids produced per unit of dry weight (YL/X %, w/w) of Cryptococcus curvatus, during growth on lactose, under nitrogen‐limited conditions.
Copper(II)‐Promoted C–C Bond Formation by Oxidative Coupling of Two C(sp3)–H Bonds Adjacent to Carbonyl Group to Construct 1,4‐Diketones and Tetrasubstituted Furans
Authors: Mao Shuai , Gao Ya‐Ru , Zhang Shao‐Liang , Guo Dong‐Dong , Wang Yong‐Qiang 
Published: December 2014

AbstractThe copper(II)‐promoted C–C bond formation from the coupling of two C(sp3)–H bonds that are adjacent to a carbonyl group was achieved. This protocol offers a simple and efficient approach to 2,3‐disubstituted 1,4‐diketones and tetrasubstituted furans. This method features a wide substrate scope and high functional group tolerance.
Statistical modeling of the hormetic dose zone and the toxic potency completes the quantitative description of hormetic dose responses
Authors: Belz Regina G. , Piepho Hans-Peter 
Published: December 2014

Abstract

Quantifying the characteristics of hormesis provides valuable insights into this low-dose phenomenon and helps to display and capture its variability. A prerequisite to do so is a statistical procedure allowing quantification of general hormetic features, namely the maximum stimulatory response, the dose range of hormesis, and the distance from the maximum stimulation to the dose where hormesis disappears. Applying extensions of a hormetic dose-response model that is well-established in plant biology provides a direct estimation of several quantities, except the hormetic dose range. Another dose range that is difficult to model directly is the distance between the dose where hormesis disappears and the dose giving 50% inhibition, known as toxic potency. The present study presents 2 further model extensions allowing for a direct quantification of the hormetic dose range and the toxic potency. Based on this, a 4-step mathematical modeling approach is demonstrated to quantify various dose-response quantities, to compare these quantities among treatments, and to interrelate hormesis features. Practical challenges are exemplified, and possible remedies are identified. The software code to perform the analysis is provided as Supplemental Data to simplify adoption of the modeling procedure. Because numerous patterns of hormesis are observed in various sciences, it is clear that the proposed approach cannot cope with all patterns; however, it should be possible to analyze a great range of hormesis patterns. Environ Toxicol Chem 2015;34:1169–1177. © 2014 SETAC
Solid inclusion complex of terpinen‐4‐ol/β‐cyclodextrin: kinetic release, mechanism and its antibacterial activity
Authors: Yang Zujin , Xiao Zuobing , Ji Hongbing 
Published: December 2014

AbstractTerpinen‐4‐ol has several biological properties, but its low stability and water‐solubility limit its use. This study reports the formation of a solid terpinen‐4‐ol/β‐cyclodextrin (β‐CD) inclusion complex via lyophilization. Release experiments were performed at various temperatures (40, 60, 80, and 100°C) with humidity of 70%. The release of terpinen‐4‐ol was significantly increased with rising temperature. Avrami's equation was used to analyse release kinetics and a good fit was observed for terpinen‐4‐ol release. In addition, the complex enhanced antibacterial activity against Staphylococcus aurueus, Pseudomonas aeruginosa and Escherichia coli, with concentration ranging from 1.25 mg/ml to 5 mg/ml. To explain the experimental data, physico‐chemical techniques have been utilized to investigate the inclusion complex of terpinen‐4‐ol with β‐CD. Finally, the possible structure of the complex was proposed by quantum chemical calculations. The results indicated that enhanced thermal stability and antibacterial activity of terpinen‐4‐ol could be attributed to the weak interactions of hydrogen bonds between terpinen‐4‐ol and β‐CD. Copyright © 2014 John Wiley & Sons, Ltd.
Incidence and long‐term survival of patients with de novo head and neck carcinoma after liver transplantation
Authors: Coordes Annekatrin , Albers Andreas E. , Lenarz Minoo , Seehofer Daniel , Puhl Gero , Pascher Andreas , Neuhaus Ruth , Neuhaus Peter , Pratschke Johann , Andreou Andreas 
Published: December 2014

AbstractBackgroundLiver transplant recipients have an increased risk of developing de novo malignancies.MethodsWe conducted a prospective evaluation of clinicopathological data and predictors for overall survival (OS) in patients with head and neck squamous cell carcinoma (HNSCC) after liver transplantation (1988 to 2010).ResultsThirty‐three of 2040 patients who underwent liver transplantation (1.6%) developed de novo HNSCC. The incidence of HNSCC in liver transplant recipients with end‐stage alcoholic liver disease (26) was 5%. After a median follow‐up of 9 years, 1‐year, 3‐year, and 5‐year OS rates were 74%, 47%, and 34%, respectively. Tumor size, cervical lymph node metastases, tumor site, and therapy (surgery only vs surgery and adjuvant radiotherapy [RT]/chemoradiotherapy [CRT] vs RT/CRT only; p < .0001) were significantly associated with OS in univariate analysis. However, surgery only predicted OS independently in multivariate analysis.ConclusionEarly diagnosis and surgical treatment of de novo HNSCC are crucial to the outcome. HNSCC risk should be taken into close consideration during posttransplantation follow‐up examinations, especially among patients with a positive history of smoking and alcohol consumption. © 2015 Wiley Periodicals, Inc. Head Neck 38: 707–714, 2016
Tobacco use and surgical outcomes in patients with head and neck cancer
Authors: Hatcher Jeanne L. , Sterba Katherine R. , Tooze Janet A. , Day Terry A. , Carpenter Matthew J. , Alberg Anthony J. , Sullivan Christopher A. , Fitzgerald Nora C. , Weaver Kathryn E. 
Published: December 2014

AbstractBackgroundTobacco use is a risk factor for head and neck cancer, but effects on postoperative outcomes are unclear.MethodsPatients with head and neck cancer (n = 89) were recruited before surgery. We assessed self‐reported tobacco use status (never, former, or current) at study entry and recent tobacco exposure via urinary cotinine on surgery day. Outcomes included hospital length of stay (LOS) and complications.ResultsMost participants reported current (32.6%) or former (52.8%) tobacco use; 43.2% were cotinine‐positive on surgery day. Complications occurred in 41.6% and mean LOS was 4.0 and 8.8 days in patients who received low and high acuity procedures, respectively. Current and former smokers were over 6 times more likely to have complications than never smokers (p = .03). For high acuity procedures, LOS was increased in current (by 4.4 days) and former smokers (by 2.3 days; p = .02).ConclusionTobacco use status is associated with postoperative complications and may distinguish at‐risk patients. © 2015 Wiley Periodicals, Inc. Head Neck 38: 700–706, 2016
Analysis of sentinel node biopsy combined with other diagnostic tools in staging cN0 head and neck cancer: A diagnostic meta‐analysis
Authors: Liao Li‐Jen , Hsu Wan‐Lun , Wang Chi‐Te , Lo Wu‐Chia , Lai Mei‐Shu 
Published: December 2014

AbstractBackgroundThe purpose of this was to find a staging strategy sensitive enough to reduce the risk of occult metastases in cN0 head and neck cancer to below 15% to 20%.MethodsA total of 73 articles were selected for analysis of the diagnostic performance in staging cN0 head and neck cancer. Hypothetical estimation of negative predictive value (NPV) was calculated based on the Bayesian theory.ResultsThe pooled estimates for sensitivity were 56.4% and 84.9% for ultrasound‐guided fine‐needle aspiration (FNA) and sentinel node biopsy (SNB). The pooled estimates for sensitivity were 47.0%, 56.6%, 48.3%, and 63.3% for CT, MRI, positron emission tomography (PET), and ultrasound, respectively. The pooled estimates for specificity were 88.9%, 82.5%, 86.2%, and 79.1% for CT, MRI, PET, and ultrasound. In estimation, the CT or MRI with SNB strategies had NPV higher than 85% even when the pretest metastatic rate was 60%.ConclusionThe SNB procedure has the best performance. A combination of CT/MRI and SNB for cN0 head and neck cancer is preferred. © 2015 Wiley Periodicals, Inc. Head Neck 38: 628–634, 2016
Thyroid thyrothymic extension: An anatomic study in a surgical series
Authors: Sheahan Patrick , O'Duffy Fergal 
Published: December 2014

ABSTRACTBackgroundThe thyrothymic extension (TTE) is a variable projection from the inferior thyroid pole along the course of the thyrothymic ligament. Awareness of the TTE is critical to ensure complete total thyroidectomy. However, there is little mention of the TTE in the literature. The purpose of the present study was to investigate the frequency of the TTE in our surgical series.MethodsWe conducted a prospective cohort study of 284 thyroid and parathyroid surgeries performed by a single surgeon.ResultsA TTE was present in 138 of 414 evaluable thyroid lobes (33.3%), with no predilection for left or right. The TTE was bilateral in 57% of cases. In 5 cases, there was significant nodular enlargement of the TTE. The inferior parathyroid gland was closely associated with 8% of TTEs.ConclusionThe TTE is a commonly encountered projection from the inferior thyroid pole. Awareness of the TTE is important to ensure complete total thyroidectomy. © 2015 Wiley Periodicals, Inc. Head Neck 38: 732–735, 2016
Interpretation of the Swedish Self Evaluation of Communication Experiences after Laryngeal cancer: Cutoff levels and minimum clinically important differences
Authors: Tuomi Lisa , Johansson Mia , Andréll Paulin , Finizia Caterina 
Published: December 2014

ABSTRACTBackgroundThe purpose of this study was to establish minimum clinically important difference (MCID) scores for the Swedish Self‐Evaluation of Communication Experiences after Laryngeal Cancer (S‐SECEL) in order to facilitate clinical interpretation and identify cutoff values for voice rehabilitation.MethodOne hundred nineteen patients with laryngeal cancer completed the S‐SECEL instrument and an anchor question regarding acceptability of speech in a social context pretreatment and 12‐month postoncologic treatment. Receiver operating characteristic (ROC) curves analysis was used for calculation of cutoff values.ResultsVoice rehabilitation cutoff values were identified for all domains (Total = 20; General = 4; Environmental = 16, and Attitudinal = 5), presenting acceptable sensitivity and specificity. Initial MCID estimates were obtained for all domains; improvement of −13 points (p < .0001) or a deterioration of +8 points (p = .035) for the Total domain.ConclusionMCID and cutoff scores for the S‐SECEL have been identified and may be used in clinical practice to help identify patients with laryngeal cancer in need of voice rehabilitation. © 2015 Wiley Periodicals, Inc. Head Neck 38: 689–695, 2016