bluuebunny/crossref_metadata_2025_split huggingface dataset:
A Remarkable Solvent Effect on the Nuclearity of Neutral Titanium(IV)‐Based Helicate Assemblies
Authors: Weekes David Michael , Diebold Carine , Mobian Pierre , Huguenard Clarisse , Allouche Lionel , Henry Marc 
Published: March 2014

AbstractThe spontaneous self‐assembly of a neutral circular trinuclear TiIV‐based helicate is described through the reaction of titanium(IV) isopropoxide with a rationally designed tetraphenolic ligand. The trimeric ring helicate was obtained after diffusion of n‐pentane into a solution with dichloromethane. The circular helicate has been characterized by using single‐crystal X‐ray diffraction study, 13C CP‐MAS NMR and 1H NMR DOSY solution spectroscopic, and positive electrospray ionization mass‐spectrometric analysis. These analytical data were compared with those obtained from a previously reported double‐stranded helicate that crystallizes in toluene. The trimeric ring was unstable in a pure solution with dichloromethane and transformed into the double‐stranded helicate. Thermodynamic analysis by means of the PACHA software revealed that formation of the double‐stranded helicates was characterized by ΔH(toluene)=−30 kJ mol−1 and ΔS(toluene)=+357 J K−1 mol−1, whereas these values were ΔH(CH2Cl2)=−75 kJ mol−1 and ΔS(CH2Cl2)=−37 J K−1 mol−1 for the ring helicate. The transformation of the ring helicate into the double‐stranded helicate was a strongly endothermic process characterized by ΔH(CH2Cl2)=+127 kJ mol−1 and ΔH(n‐pentane)=+644 kJ mol−1 associated with a large positive entropy change ΔS=+1115 J K−1⋅mol−1. Consequently, the instability of the ring helicate in pure dichloromethane was attributed to the rather high dielectric constant and dipole moment of dichloromethane relative to n‐pentane. Suggestions for increasing the stability of the ring helicate are given.
Silver‐Free Two‐Component Approach in Gold Catalysis: Activation of [LAuCl] Complexes with Derivatives of Copper, Zinc, Indium, Bismuth, and Other Lewis Acids
Authors: Fang Weizhen , Presset Marc , Guérinot Amandine , Bour Christophe , Bezzenine‐Lafollée Sophie , Gandon Vincent 
Published: March 2014

AbstractComplexes of type [LAuCl] (L=phosphine, phosphite, NHC and others) are widely employed in homogeneous catalysis, however, they are usually inactive as such and must be used jointly with a halide scavenger. To date, this role has mostly been entrusted to silver salts (AgSbF6, AgPF6, AgBF4, AgOTf, etc.). However, silver salts can be the source of deactivation processes or side reactions, so it is sometimes advisable to use silver‐free cationic gold complexes, which can be difficult to synthesize and to handle compared with the more robust chloride. We show in this study that various Lewis acids of the transition and main group metal families are expedient substitutes to silver salts. We have tested CuI, CuII, ZnII, InIII, SiIV, BiIII, and other salts in a variety of typical AuI‐catalyzed transformations, and the results have revealed that [LAuCl] can form active species in their presence.
Cyclometalated Iridium(III) Bipyridyl–Phenylenediamine Complexes with Multicolor Phosphorescence: Synthesis, Electrochemistry, Photophysics, and Intracellular Nitric Oxide Sensing
Authors: Law Wendell Ho‐Tin , Leung Kam‐Keung , Lee Lawrence Cho‐Cheung , Poon Che‐Shan , Liu Hua‐Wei , Lo Kenneth Kam‐Wing 
Published: March 2014

AbstractWe present a new class of phosphorescent cyclometalated iridium(III) bipyridyl–phenylenediamine complexes [Ir(N^C)2(bpy‐DA)](PF6) (bpy‐DA=4‐(N‐(2‐amino‐5‐methoxyphenyl)aminomethyl)‐4′‐methyl‐2,2′‐bipyridine; HN^C=2‐(2,4‐difluorophenyl)pyridine (Hdfppy) (1 a), 2‐phenylpyridine (Hppy) (2 a), 2‐phenylquinoline (Hpq) (3 a), 2‐phenylcinchoninic acid methyl ester (Hpqe) (4 a)) and their triazole counterparts [Ir(N^C)2(bpy‐T)](PF6) (bpy‐T=4‐((6‐methoxybenzotriazol‐1‐yl)methyl)‐4′‐methyl‐2,2′‐bipyridine; HN^C=Hdfppy (1 b), Hppy (2 b), Hpq (3 b), Hpqe (4 b)). Upon photoexcitation, the diamine complexes exhibited fairly weak green to red phosphorescence under ambient conditions whereas the triazole derivatives emitted strongly. The photophysical properties of complexes 2 a and 2 b have been studied in more detail. Upon protonation, the diamine complex 2 a displayed increased emission intensity, but the emission properties of its triazole counterpart complex 2 b were independent on the pH value of the solution. Also, complex 2 a was found to be readily converted into complex 2 b upon reaction with NO under aerated conditions, resulting in substantial emission enhancement of the solution. The reaction was highly specific toward NO over other reactive oxygen and nitrogen species (RONS) as revealed by spectroscopic analyses. The lipophilicity and cellular uptake efficiency of the diamine complexes have been examined and correlated to their molecular structures. Also, cell‐based assays showed that these complexes were noncytotoxic toward human cervix epithelioid carcinoma (HeLa) cells (at 10 μM, 4 h, percentage survival ≈80–95 %). Additionally, the diamine complexes have been used to visualize intracellular NO generated both exogenously in HeLa cells and endogenously in RAW 264.7 murine macrophages by laser‐scanning confocal microscopy.
State‐of‐the‐science of patient navigation as a strategy for enhancing minority clinical trial accrual
Authors: Ghebre Rahel G. , Jones Lovell A. , Wenzel Jennifer A. , Martin Michelle Y. , Durant Raegan W. , Ford Jean G. 
Published: March 2014

BACKGROUNDPatient navigation programs are emerging that aim to address disparities in clinical trial participation among medically underserved populations, including racial/ethnic minorities. However, there is a lack of consensus on the role of patient navigators within the clinical trial process as well as outcome measures to evaluate program effectiveness.METHODSA review of the literature was conducted of PubMed, Medline, CINHAL, and other sources to identify qualitative and quantitative studies on patient navigation in clinical trials. The search yielded 212 studies, of which only 12 were eligible for this review.RESULTSThe eligible studies reported on the development of programs for patient navigation in cancer clinical trials, including training and implementation among African Americans, American Indians, and Native Hawaiians. A low rate of clinical trial refusal (range, 4%‐6%) was reported among patients enrolled in patient navigation programs. However, few studies reported on the efficacy of patient navigation in increasing clinical treatment trial enrollment.CONCLUSIONSOutcome measures are proposed to assist in developing and evaluating the efficacy and/or effectiveness of patient navigation programs that aim to increase participation in cancer clinical trials. Future research is needed to evaluate the efficacy of patient navigators in addressing barriers to clinical trial participation and increasing enrollment among medically underserved cancer patients. Cancer 2014;120(7 suppl):1122–30. © 2014 American Cancer Society.
A formal analysis of authentication protocols for mobile devices in next generation networks
Authors: Aiash Mahdi 
Published: March 2014

SummaryNext Generation Networks comprise a wide variety of access technologies such as 2G/3G, WLAN as well as the Long‐Term Evolution (LTE) networks. In this environment, mobile devices are expected to store sensitive data and represent users to access the underlying networks and connect to a wide variety of sensitive servers. It is crucial, in this sense, for end users to trust their mobile devices and for all transactions using them to be secure. Therefore, a number of communication frameworks in Next Generation Networks have been working on designing device authentication protocols that achieve mutual authentication between users and mobile terminals. This paper analyses some of these protocols and introduces two new device authentication protocols, verifies them using formal methods approach and discusses how they achieved desired security proprieties. The performance analysis highlights another advantage of the proposed protocols. Copyright © 2014 John Wiley & Sons, Ltd.
Framework Stability and Brønsted Acidity of Isomorphously Substituted Interlayer‐Expanded Zeolite COE‐4: A Density Functional Theory Study
Authors: Li Haichao , Zhou Danhong , Tian Dongxu , Shi Chuan , Müller Ulrich , Feyen Mathias , Yilmaz Bilge , Gies Hermann , Xiao Feng‐Shou , De Vos Dirk , Yokoi Toshiyuki , Tatsumi Takashi , Bao Xinhe , Zhang Weiping 
Published: March 2014

AbstractCOE‐4 zeolites possess a unique two‐dimensional ten‐ring pore structure with the Si(OH)2 hydroxyl groups attached to the linker position between the ferrierite‐type layers, which has been demonstrated through the interlayer‐expansion approach in our previous work (H. Gies et al. Chem. Mater.­ 2012, 24, 1536). Herein, density functional theory is used to study the framework stability and Brønsted acidity of the zeolite T‐COE‐4, in which the tetravalent Si is isomorphously substituted by a trivalent Fe, B, Ga, or Al heteroatom at the linker position. The influences of substitution energy and equilibrium geometry parameters on the stability of T‐COE‐4 are investigated in detail. The relative acid strength of the linker position is revealed by the proton affinity, charge analysis, and NH3 adsorption. It is found that the range of the 〈T‐O‐Si〉 angles is widened to maintain the stability of isomorphously substituted T‐COE‐4 zeolites. The smaller the 〈O1‐T‐O2〉 bond angle is, the more difficult is to form the regular tetrahedral unit. Thus, the substitution energies at the linker positions increase in the following sequence: Al‐COE‐4 < Ga‐COE‐4 < Fe‐COE‐4 < B‐COE‐4. The adsorption of NH3 as a probe molecule indicates that the acidity can affect the hydrogen‐bonding interaction between (NH⋅⋅⋅O2) and (N⋅⋅⋅HO2). The relative Brønsted‐acid strength of the interlayer‐expanded T‐COE‐4 zeolite decreases in the order of Al‐COE‐4 > Ga‐COE‐4 > Fe‐COE‐4 > B‐COE‐4. These findings may be helpful for the structural design and functional modification of interlayer‐expanded zeolites.
Photocatalytic Carboxylation of Organic Substrates with Carbon Dioxide at Zinc Sulfide with Deposited Ruthenium Nanoparticles
Authors: Baran Tomasz , Dibenedetto Angela , Aresta Michele , Kruczała Krzysztof , Macyk Wojciech 
Published: March 2014

AbstractPhotocatalytic carboxylation of acetylacetone with carbon dioxide has been performed by using ZnS‐based photocatalysts. The formation of two isomeric carboxylic acids, as proven by IR and 13C NMR spectroscopy, was observed. The reaction yield was enhanced after deposition of ruthenium nanoparticles on ZnS. The reaction encompasses ruthenium‐mediated one‐electron reduction of CO2 to CO2.− with electrons from the conduction band of ZnS and one‐hole oxidation of acetylacetone to the relevant radical. Coupling of photogenerated radicals leads to the formation of carboxylic acids. Generation of CO2.− has been confirmed by spin‐trapping EPR measurements. The process described herein may find applications for the solar‐light‐driven green synthesis of Cn+1 carboxylic compounds from Cn substrates by utilising carbon dioxide.
Recent Advances in Carbon Dioxide Capture, Fixation, and Activation by using N‐Heterocyclic Carbenes
Authors: Yang Longhua , Wang Hongming 
Published: March 2014

AbstractIn the last two decades, CO2 emission has caused a lot of environmental problems. To mitigate the concentration of CO2 in the atmosphere, various strategies have been implemented, one of which is the use of N‐heterocyclic carbenes (NHCs) and related complexes to accomplish the capture, fixation, and activation of CO2 effectively. In this review, we summarize CO2 capture, fixation, and activation by utilizing NHCs and related complexes; homogeneous reactions and their reaction mechanisms are discussed. Free NHCs and NHC salts can capture CO2 in both direct and indirect ways to form imidazolium carboxylates, and they can also catalyze the reaction of aromatic aldehydes with CO2 to form carboxylic acids and derivatives. Moreover, associated with transition metals (TMs), NHCs can form NHC–TM complexes to transform CO2 into industrial acid or esters. Non‐metal–NHC complexes can also catalyze the reactions of silicon and boron complexes with CO2. In addition, catalytic cycloaddition of epoxides with CO2 is another effective function of NHC complexes, and NHC ionic liquids perform excellently in this aspect.
Entropically Favored Adsorption of Cellulosic Molecules onto Carbon Materials through Hydrophobic Functionalities
Authors: Yabushita Mizuho , Kobayashi Hirokazu , Hasegawa Jun‐ya , Hara Kenji , Fukuoka Atsushi 
Published: March 2014

AbstractCarbon‐based materials have attracted interest as high‐performance catalysts for the aqueous‐phase conversion of cellulose. The adsorption of β‐glucans plays a crucial role in the catalytic performance of carbons, although the primary driving force and details of the adsorption process remain unclear. This study demonstrates that adsorption occurs at hydrophobic sites on the carbon surface and that hydrophilic groups are not involved. Analysis of adsorption temperature dependence also reveals that the entropy change associated with adsorption is positive. Our results indicate that adsorption occurs by entropically driven hydrophobic interactions in addition to CH–π hydrogen bonding. These same CH–π hydrogen bonds are also confirmed by DFT calculations. The adsorption of β‐glucans on carbons is significantly stronger than the affinity between β‐glucans. The adsorption equilibrium constants of β‐glucans on carbons increase exponentially with increasing degrees of polymerization, which supports the theory of strong interactions between the carbon and the long β‐glucans found in cellulose.
Switching to multiple daily injection therapy with glulisine improves glycaemic control, vascular damage and treatment satisfaction in basal insulin glargine‐injected diabetic patients
Authors: Yanagisawa Katsuyuki , Ashihara Junya , Obara Shinji , Wada Norio , Takeuchi Masayoshi , Nishino Yuri , Maeda Sayaka , Ishibashi Yuji , Yamagishi Sho‐ichi 
Published: March 2014

AbstractBackgroundBasal and bolus insulin therapy is required for strict blood control in diabetic patients, which could lead to prevention of vascular complications in diabetes. However, the optimal combination regimen is not well established.MethodsFifty‐nine diabetic patients (49 type 1 and 10 type 2; 52.9 ± 13.3 years old) whose blood glucose levels were uncontrolled (HbA1c > 6.2%) by combination treatment of basal insulin glargine with multiple daily pre‐meal injections of bolus short‐acting insulin [aspart (n = 19), lispro (n = 37) and regular human insulin (n = 3)] for at least 8 weeks were enrolled in this study. We examined whether glycaemic control and vascular injury were improved by replacement of short‐acting insulin with glulisine. Patient satisfaction was assessed with Diabetes Treatment Satisfaction Questionnaire.ResultsAlthough bolus and basal insulin doses were almost unchanged before and after replacement therapy, switching to glulisine insulin for 24 weeks significantly decreased level of HbA1c, advanced glycation end products (AGEs), soluble receptor for AGEs (sRAGE), monocyte chemoattractant protein‐1 (MCP‐1) and urinary albumin excretion. In multiple stepwise regression analysis, change in MCP‐1 values from baseline (ΔMCP‐1) was a sole determinant of log urinary albumin excretion. ΔAGEs and ΔsRAGE were independently correlated with each other. The relationship between ΔMCP‐1 and ΔsRAGE was marginally significant (p = 0.05). Replacement of short‐acting insulin by glulisine significantly increased Diabetes Treatment Satisfaction Questionnaire scores.ConclusionsOur present study suggests that combination therapy of glargine with multiple daily pre‐meal injections of glulisine might show superior efficacy in controlling blood glucose, preventing vascular damage and improving treatment satisfaction in diabetic patients. Copyright © 2014 John Wiley & Sons, Ltd.
Lixisenatide treatment improves glycaemic control in Asian patients with type 2 diabetes mellitus inadequately controlled on metformin with or without sulfonylurea: a randomized, double‐blind, placebo‐controlled, 24‐week trial (GetGoal‐M‐Asia)
Authors: Yu Pan Chang , Han Ping , Liu Xiaoming , Yan Shengli , Feng Ping , Zhou Zhiguang , Lv Xiaofeng , Tian Hui , Jin Kui Yang , Su Benli , Shang Shuhua , Niemoeller Elisabeth 
Published: March 2014

AbstractBackgroundThis study assessed the efficacy and safety of the once‐daily glucagon‐like peptide‐1 receptor agonist, lixisenatide, in Asian patients with type 2 diabetes mellitus inadequately controlled on metformin ± sulfonylurea.MethodsIn this 24‐week, double‐blind, placebo‐controlled, multinational study, patients were randomized to lixisenatide 20 µg once daily or placebo. The primary endpoint was absolute change in glycated haemoglobin (HbA1c) from baseline to week 24.ResultsA total of 391 patients were randomized. Lixisenatide significantly reduced HbA1c levels compared with placebo (LS mean difference: −0.36%, p = 0.0004). A significantly higher proportion of lixisenatide‐treated patients achieved HbA1c targets of <7% (p = 0.003) and ≤6.5% (p = 0.001) versus placebo. Lixisenatide was associated with a statistically significant reduction in 2‐h postprandial plasma glucose after a standardized breakfast versus placebo (LS mean difference: −4.28 mmol/L, p < 0.0001) and a significant reduction in fasting plasma glucose (p = 0.0109). There was no difference in weight loss versus placebo, with a modest reduction in body weight reported for both groups (lixisenatide: −1.50 kg, placebo: −1.24 kg; p = 0.296). The incidence of treatment‐emergent adverse events (TEAEs) was 64.3% with lixisenatide versus 47.4% with placebo, with serious TEAEs reported in 1.5% versus 2.1% of patients, respectively. The most common TEAE in the lixisenatide group was nausea (16.3% vs 2.6% with placebo). The incidence of symptomatic hypoglycaemia was 5.6% with lixisenatide treatment and 2.6% with placebo (p = 0.1321), with no severe symptomatic hypoglycaemia events reported.ConclusionsIn Asian patients with type 2 diabetes mellitus insufficiently controlled on metformin ± sulfonylurea, lixisenatide significantly improved glycaemic control and was well tolerated during the 24‐week study. © 2014 The Authors. Diabetes/Metabolism Research and Reviews published by John Wiley & Sons, Ltd.
Quantitative analysis reveals dominance of gliogenesis over neurogenesis in an adult brainstem oscillator
Authors: Sîrbulescu Ruxandra F. , Ilieş Iulian , Zupanc Günther K.H. 
Published: March 2014

ABSTRACTNeural stem/progenitor cells in the neurogenic niches of the adult brain are widely assumed to give rise predominantly to neurons, rather than glia. Here, we performed a quantitative analysis of the resident neural progenitors and their progeny in the adult pacemaker nucleus (Pn) of the weakly electric fishApteronotus leptorhynchus. Approximately 15% of all cells in this brainstem nucleus are radial glia‐like neural stem/progenitor cells. They are distributed uniformly within the tissue and are characterized by the expression of Sox2 and Meis 1/2/3. Approximately 2–3% of them are mitotically active, as indicated by expression of proliferating cell nuclear antigen. Labeling of proliferating cells with a single pulse of BrdU, followed by chases of up to 100 days, revealed that new cells are generated uniformly throughout the nucleus and do not undergo substantial migration. New cells differentiate into S100+ astrocytes and Hu C/D+ small interneurons at a ratio of 4:1, reflecting the proportions of the total glia and neurons in this brain region. The continuous addition of new cells leads to a diffuse growth of the Pn, which doubles in volume and total cell number over the first 2 years following sexual maturation of the fish. However, the number of pacemaker and relay cells, which constitute the oscillatory neural network, remains constant throughout adult life. We hypothesize that the dominance of gliogenesis is an adaptation to the high‐frequency firing of the oscillatory neurons in this nucleus. © 2014 Wiley Periodicals, Inc. Develop Neurobiol 74: 934–952, 2014
The additive burden of iron deficiency in the cardiorenal–anaemia axis: scope of a problem and its consequences
Authors: Klip IJsbrand T. , Jankowska Ewa A. , Enjuanes Cristina , Voors Adriaan A. , Banasiak Waldemar , Bruguera Jordi , Rozentryt Piotr , Polonski Lech , van Veldhuisen Dirk J. , Ponikowski Piotr , Comin‐Colet Josep , van der Meer Peter 
Published: March 2014

AimsIron deficiency (ID), anaemia, and chronic kidney disease (CKD) are common co‐morbidities in chronic heart failure (CHF) and all independent predictors of unfavourable outcome. The combination of anaemia and CKD in CHF has been described as the cardiorenal–anaemia syndrome. However, the role of ID within this complex interplay of co‐existing pathologies is unclear.Methods and resultsWe studied the clinical correlates of ID (defined as ferritin <100 µg/L or 100–299 µg/L in combination with a transferrin saturation <20%, anaemia) and renal dysfunction (defined as estimated glomerular filtration rate <60 mL/min/1.73 m2) and their prognostic implications in an international pooled cohort, comprising 1506 patients with CHF. Mean age was 64 ± 13 years, 74.2% were male, and 47.3% were in NYHA functional class III. The presence of ID, anaemia, CKD, or a combination of these co‐morbidities was observed in 69.3% of the patients. During a median (Q1–Q3) follow‐up of 1.92 years (1.18–3.26 years), 440 patients (29.2%) died. Eight‐year survival rates decreased significantly from 58.0% for no co‐morbidities to 44.6, 33.0, and 18.4%, for one, two, or three co‐morbidities, respectively (P < 0.001). Multivariate hazard models revealed ID to be the key determinant of prognosis, either individually (P = 0.04) or in combination with either anaemia (P = 0.006), CKD (P = 0.03), or both (P = 0.02).ConclusionsIron deficiency frequently overlaps with anaemia and/or CKD in CHF. The presence of ID amplifies mortality risk, either alone or in combination with anaemia, CKD, or both, making it a potential viable therapeutic target.
Synthesis of Unexpected Bifunctionalized Thiazoles by Nucleophilic Attack on Allenyl Isothiocyanate
Authors: Jawabrah Al‐Hourani Baker , Richter Frank , Vrobel Kai , Banert Klaus , Korb Marcus , Rüffer Tobias , Walfort Bernhard , Lang Heinrich 
Published: March 2014

AbstractTreatment of allenyl isothiocyanate with a variety of nucleophiles leads to 5‐methylthiazoles with a functional group at the 2‐position. The same pattern of reactivity is also seen with N‐aminophthalimide. In the presence of azide salt, hydrazoic acid, or N,N‐disubstituted hydroxylamines, however, allenyl isothiocyanate is converted into bifunctionalized thiazoles. We explain the formation of these products by nucleophilic addition at the isothiocyanato moiety followed by ring closure and an N–N or N–O cleavage reaction to generate short‐lived 2‐imino‐5‐methylidenethiazole or 5‐methylidenethiazol‐2‐one. Such intermediates are trapped by addition reactions to give the final heterocyclic compounds. In the case of N,N‐disubstituted hydroxylamines, the primary addition products with allenyl isothiocyanate can be detected as unstable intermediates by IR and NMR spectroscopy.