bluuebunny/crossref_metadata_2025_split huggingface dataset:
Metal‐Free Intermolecular Azide–Alkyne Cycloaddition Promoted by Glycerol
Authors: Rodríguez‐Rodríguez Marta , Gras Emmanuel , Pericàs Miquel A. , Gómez Montserrat 
Published: November 2015

AbstractMetal‐free intermolecular Huisgen cycloadditions using nonactivated internal alkynes have been successfully performed in neat glycerol, both under thermal and microwave dielectric heating. In sharp contrast, no reaction occurs in other protic solvents, such as water, ethanol, or diols. DFT calculations have shown that the BnN3/glycerol adduct promotes a more important stabilization of the corresponding LUMO than that produced in the analogous BnN3/alcohol adducts, favoring the reactivity with the alkyne in the first case. The presence of copper salts in the medium did not change the reaction pathway (Cu(I) acts as spectator), except for disubstituted silylalkynes, for which desilylation takes place in contrast to the metal‐free system.
Ligand‐Controlled Synthesis of [3]‐ and [4]Cyclo‐9,9‐dimethyl‐2,7‐fluorenes through Triangle‐ and Square‐Shaped Platinum Intermediates
Authors: Kayahara Eiichi , Qu Rui , Kojima Mitsuru , Iwamoto Takahiro , Suzuki Toshiyasu , Yamago Shigeru 
Published: November 2015

AbstractThe syntheses of [3]‐ and [4]cyclo‐9,9‐dimethyl‐2,7‐fluorenes ([3] and [4]CFRs), cyclic trimer, and tetramers of 9,9‐dimethyl‐2,7‐fluorene (FR), respectively, were achieved by the platinum‐mediated assembly of FR units and subsequent reductive elimination of platinum. A triangle‐shaped tris‐platinum complex and a square‐shaped tetra‐platinum complex were obtained by changing the platinum ligand. The structure of the triangle complex was unambiguously determined by X‐ray crystallographic analysis. Reductive elimination of each complex gave [3] and [4]CFRs. Two rotamers of [3]CFR were sufficiently stable at room temperature and were separated by chromatography. The physical properties of the CFRs were also investigated theoretically and experimentally.
Membrane fouling control and performance enhancement of ultrafiltration of latex effluent
Authors: Abdelrasoul Amira , Doan Huu , Lohi Ali , Cheng Chil‐Hung 
Published: November 2015

AbstractThe objective of the present study was to minimize membrane fouling of a latex solution either through improving the membrane surface charge or using a pretreated feed. Hydrophilic polysulphone (PSU) and Ultrafilic flat membranes, with a molecular weight cut‐off (MWCO) of 60 000 and 100 000 dalton, respectively, were implemented under a constant flow rate and cross‐flow mode in ultrafiltration of simulated latex effluent. Hydrophobic polyvinylidene difluoride membrane (PVDF) with a MWCO of 100 000 dalton was also tested. The influence of linear alkyl benzene sulphonate (LAS) on the ionic strength of the simulated latex effluent and the surface charge of latex particles at different LAS concentrations was investigated. LAS was also used, at different concentrations and various treatment times, to ensure the enhancement of the antifouling characteristics of the membrane surface. It was concluded that the LAS‐treated membrane surface is much more favourable than the pH‐changed feed pre‐treatment. As such, the total mass of fouling decreased by 44.00 % and 29.60 % in the cases of treated PVDF membrane surface with LAS at a concentration of 0.0001 g/L, and treated latex feed at pH 11, respectively. Nevertheless, LAS was considered to be an ineffective pre‐treatment for limiting the fouling propensity of latex solutions using hydrophilic membranes even at high concentrations and long treatment times.
Power consumption, gas holdup, and mass‐transfer coefficient of triple‐impeller configurations in a stirred vessel with vertical tubular coils
Authors: Wan Xun , Takahata Yasuyuki , Takahashi Koji 
Published: November 2015

AbstractThree kinds of impeller combinations (3 × 4WHd, HB + 2 × 4WHd, 2 × HB + 4WHd) were used to investigate the effects of coil baffles on system power consumption, gas holdup, and mass transfer coefficient. The experiments were performed in a dish‐bottomed vessel with a diameter of 0.29 m. Results of the power consumption experiments show that at the same rotation speed and an increasing rate of gas flow, the power consumptions of 3 × 4WHd and 2 × HB + 4WHd with coil baffles are almost the same as that of a system with four planar baffles, but there is a clear power draw for the HB + 2  × 4WHd combination. At rotational speeds of 250–350 rpm, the largest power draws for the 2 × HB + 4WHd, HB + 2  × 4WHd, and 3 × 4WHd impeller combinations equipped with coil baffles are 27, 25, and 15 %, respectively. The gas holdup experiment shows that with installation of coil baffles in the vessel, axial and radial impeller combinations can achieve gas dispersion identical to that attained with planar baffles. At the same power input and superficial gas rate over a wide range of gas velocities, the kLa values of the coil baffles for the 3 × 4WHd and 2 × HB + 4WHd combinations are almost identical to those of a conventional system with four baffles. However, in the HB + 2 × 4WHd system, kLa values of the coil baffles are 15 % higher than for planar baffles at low gas velocities and 30 % higher at high superficial gas rates. Finally, all data from the experiments on gas holdup and kLa values may be correlated through the equations and .
Silver(I)‐Catalyzed Synthesis of β‐Oxopropylcarbamates from Propargylic Alcohols and CO2 Surrogate: A Gas‐Free Process
Authors: Song Qing‐Wen , Zhou Zhi‐Hua , Yin Hong , He Liang‐Nian 
Published: November 2015

AbstractThe utilization of carbon dioxide poses major challenges owing to its high thermodynamic stability and kinetic inertness. To circumvent these problems, a simple reaction system is reported comprising ammonium carbamates as carbon dioxide surrogates, propargylic alcohols, and a silver(I) catalyst, for the effective conversion of a wide range of alcohols and secondary amines into the corresponding β‐oxopropylcarbamates. A key feature of this strategy includes quantitative use of a carbon resource with high product yields under gas‐free and mild reaction conditions. Notably, this catalytic protocol also works well for the carboxylative cyclization of propargylic amines and carbon dioxide surrogates to afford 2‐oxazolidinones.
Fluctuating fire regimes and their historical effects on genetic variation in an endangered shrubland specialist
Authors: Vázquez‐Miranda Hernán , Barr Kelly R. , Farquhar C. Craig , Zink Robert M. 
Published: November 2015

AbstractThe Pleistocene was characterized by worldwide shifts in community compositions. Some of these shifts were a result of changes in fire regimes, which influenced the distribution of species belonging to fire‐dependent communities. We studied an endangered juniper–oak shrubland specialist, the black‐capped vireo (Vireo atricapilla). This species was locally extirpated in parts of Texas and Oklahoma by the end of the 1980s as a result of habitat change and loss, predation, brood parasitism, and anthropogenic fire suppression. We sequenced multiple nuclear loci and used coalescence methods to obtain a deeper understanding of historical population trends than that typically available from microsatellites or mtDNA. We compared our estimated population history, a long‐term history of the fire regime and ecological niche models representing the mid‐Holocene, last glacial maximum, and last interglacial. Our Bayesian skyline plots showed a pattern of historical population fluctuation that was consistent with changing fire regimes. Genetic data suggest that the species is genetically unstructured, and that the current population should be orders of magnitude larger than it is at present. We suggest that fire suppression and habitat loss are primary factors contributing to the recent decline of the BCVI, although the role of climate change since the last glacial maximum is unclear at present.
TGF‐β induces the differentiation of human CXCL13‐producing CD4+ T cells
Authors: Kobayashi Shio , Watanabe Takeshi , Suzuki Ryo , Furu Moritoshi , Ito Hiromu , Ito Juichi , Matsuda Shuichi , Yoshitomi Hiroyuki 
Published: November 2015

In the ectopic lymphoid‐like structures present in chronic inflammatory conditions such as rheumatoid arthritis, a subset of human effector memory CD4+ T cells that lacks features of follicular helper T (Tfh) cells produces CXCL13. Here, we report that TGF‐β induces the differentiation of human CXCL13‐producing CD4+ T cells from naïve CD4+ T cells. The TGF‐β‐induced CXCL13‐producing CD4+ T cells do not express CXCR5, B‐cell lymphoma 6 (BCL6), and other Tfh‐cell markers. Furthermore, expression levels of CD25 (IL‐2Rα) in CXCL13‐producing CD4+ T cells are significantly lower than those in FoxP3+ in vitro induced Treg cells. Consistent with this, neutralization of IL‐2 and knockdown of STAT5 clearly upregulate CXCL13 production by CD4+ T cells, while downregulating the expression of FoxP3. Furthermore, overexpression of FoxP3 in naïve CD4+ T cells downregulates CXCL13 production, and knockdown of FoxP3 fails to inhibit the differentiation of CXCL13‐producing CD4+ T cells. As reported in rheumatoid arthritis, proinflammatory cytokines enhance secondary CXCL13 production from reactivated CXCL13‐producing CD4+ T cells. Our findings demonstrate that CXCL13‐producing CD4+ T cells lacking Tfh‐cell features differentiate via TGF‐β signaling but not via FoxP3, and exert their function in IL‐2‐limited but TGF‐β‐rich and proinflammatory cytokine‐rich inflammatory conditions.
Unusually low pour point of fatty acid methyl esters with low saturated fatty acid content
Authors: Nie Jieyu , Wang Sunmin , Emami Shahram , Falk Kevin , Shen Jianheng , Reaney Martin J.T. 
Published: November 2015

Many oilseeds grown in Canada have unusual fatty acid profiles including Cruciferous oilseed varieties that have very low levels (<3%) of saturated fatty acid. In this study oil samples were obtained from five cultivars of Brassica rapa L., seven cultivars of Brassica napus L. and five cultivars from other oilseeds species namely Brassica juncea L., Sinapis alba L., Camelina sativa L. and Linum usitatissimum L. The fatty acid profile, cloud point (CP) and pour point (PP) were determined for each oil sample. Fatty acid methyl esters (FAME) were synthesized from each oil sample. The saturated fatty acid content was highly correlated (R2 = 0.93) with PP in methyl esters prepared from Brassica sp. oils. In addition, we identified three publications where PP was measured on fatty acid methyl esters and found that the correlation of PP with saturated fat content was consistent with data presented herein. Since B. rapa oil exhibited superior low temperature properties, it was chosen for further studies of oxidative stability. B. rapa cultivars, with less than 3.5% saturated fat and less than 20% polyunsaturated fat, can be an excellent feedstock for production of oils with improved cold fluidity and oxidative stability.Practical applications: Here, we report studies on the relationship of saturated fat level with cold flow properties and polyunsaturated fat level with oxidative stability in fatty acid methyl esters made from oils with less than 10% total saturates. This research reveals potential keys to producing FAME with good oxidative stability and excellent low temperature performance. Brassica rapa with less than 3.5% saturated fat and less than 20% polyunsaturated fat has a pour point that is substantially better than oils with higher levels of saturated FAME. The lowest observed pour point was −21°C. FAME with this low temperature property could be used in a range of applications, such as cold‐flow improvers for biodiesel or bio‐lubricants.Effect of saturated fatty acid content on pour point (PP) of fatty acid methyl ester.
Reinvestigation of the Nitration of Tri­chloroethene – Subsequent Reactions of the Products and Evaluation of Their Anti­microbial and Antifungal Activity
Authors: Zapol'skii Viktor A. , Namyslo Jan C. , Sergeev Galina , Brönstrup Mark , Gjikaj Mimoza , Kaufmann Dieter E. 
Published: November 2015

AbstractThe nitration reaction of trichloroethene (1) to main products trichloronitroethene (TCNiE2, up to 60.8 %, by GC), 1,1,2,2‐tetrachloro‐1‐nitroethane (8, up to 25.1 %, by GC), and 1,2,2‐trichloro‐2‐nitroethyl [chloro(nitro)methylene]azinate (9, up to 8.0 %, by GC) was comprehensively investigated and optimized. Different 1,1‐diamino‐2‐chloro‐2‐nitroethenes, 2‐nitroethoxyguanidines, and rareO‐(1,2,2‐trichloro‐2‐nitroethyl) oximes and carbimidoyl halides with unique formulas R–O–N=C(NO2)NRR1and R–O–N=C(Hal)NRR1, respectively, were obtained from these nitration products in yields up to 91 %. The structure of (E)‐morpholino(nitro)methanoneO‐(1,2,2‐trichloro‐2‐nitroethyl) oxime (19) was proven by single‐crystal X‐ray diffraction analysis. In addition, the antimicrobial and antifungal activity of the synthesized compounds was examined. Notably,N‐(1,2,2‐trichloro‐2‐nitroethoxy)‐3,4‐dihydroisoquinoline‐2(1H)carbimidoyl chloride (27) inhibited the growth of methicillin‐resistant and sensitiveStaphylococcus aureuswith minimum inhibitory concentrations of 1.3 μg mL–1, and reduced the viability of the MCF‐7 cancer cell line with an IC50of 0.2 μg/mL.
Iodine‐Catalyzed Synthesis of Highly Functionalized 1H‐Indene Derivatives from Michael Adducts of o‐Alkynylarene Chalcones with Diethyl Malonate
Authors: Akbar Sikkandarkani , Srinivasan Kannupal 
Published: November 2015

AbstractUpon treatment with a substoichiometric amount of iodine in ethanol under reflux conditions, the Michael adducts of o‐alkynylarene chalcones with diethyl malonate underwent 5‐exo‐dig Conia‐ene cyclization followed by isomerization to yield highly functionalized 1H‐indene derivatives in good yields.
An Eco‐Friendly Route to N‐Arylindoles by Iron‐Catalyzed [2+2+2] Cycloaddition of Diynes with (Indol‐1‐yl)alkynes
Authors: Chowdhury Hrishikesh , Chatterjee Nachiketa , Goswami Avijit 
Published: November 2015

AbstractA new pathway to the synthesis of N‐arylindoles has been developed that proceeds through an iron‐catalyzed [2+2+2] cycloaddition reaction between diynes and indole‐N‐alkynes. The reaction is carried out in ethanol and employs a catalyst system that consists of iron(II) chloride tetrahydrate as the metal source, 2‐[(2,6‐diisopropylphenyl)iminomethyl]pyridine (dipimp) as the ligand, and zinc as the reducing agent. The method provides efficient access to 3‐carbonyl/ester‐substituted (indol‐1‐yl)arenes in good to excellent yields under green reaction conditions, and these products are structurally similar to other N‐arylindole derivatives with potential medicinal value.
Enzyme‐free Glucose Sensor Fabricated by Nanorods Decorated Nanopore Arrays on Biomedical Stainless Steel
Authors: Zhang Chao , Ni Hongwei , Chen Rongsheng , Zhan Weiting , Liu Shan , Zhang Bowei , Lei Rui , Zha Yaxin 
Published: November 2015

AbstractA novel enzyme‐free glucose sensor was proposed by preparation of nanorods decorated nanopore arrays (NRs/NPAs) on 316L stainless steel simply by electrochemical treatments. The NRs/NPAs sensor displays two linear ranges towards glucose determination, one range from 1 μM to 1.2 mM with a sensitivity of 202.2 μA ⋅ cm−2 ⋅ mM−1, another range from 1.2 mM to 7.7 mM with a sensitivity of 59.18 μA⋅cm−2 ⋅ mM−1. The detection limit is 0.5 μM. The NRs/NPAs electrode exhibits excellent stability, good selectivity and reproducibility, rendering it suitable for glucose monitoring.
Fear of Unemployment and its Effect on the Mental Health of Spouses
Authors: Bünnings Christian , Kleibrink Jan , Weßling Jens 
Published: November 2015

SummaryUnemployment has been shown to have adverse effects on different aspects of a person's life, and even the fear of losing a job affects individuals negatively. In addition, not only the individuals directly affected but also their spouses and other family members might be affected. Using data from the German Socio‐economic Panel, this study analyzes the relationship between individual job worries and spouse's mental well‐being. The empirical results remain robust to different specifications and indicate that fear of job loss is negatively related to spouses' mental well‐being and that this relationship seems to be stronger in single‐income than in dual‐income households. Copyright © 2015 John Wiley & Sons, Ltd.
Physical Organic Chemistry and the Origin of Life Problem: A Personal Perspective
Authors: Pross Addy 
Published: November 2015

AbstractThe origin of life (OOL) question might be considered physical organic chemistry’s ultimate challenge, yet despite continuing efforts over close to a century, the problem remains unresolved. In this personal perspective, I discuss some aspects of that challenge, and argue that notwithstanding the general perception that physical organic chemistry is a research area in decline, the discipline was, and continues to be, the most relevant one for tackling the OOL problem. Systems chemistry, a newly emergent branch of physical organic chemistry, which, inter alia, deals with replicating chemical systems and the networks they establish, reveals that physical organic chemistry, though in different guise, is alive and kicking. The broad direction ahead seems illuminated.
Monaural or binaural sound deprivation in postlingual hearing loss: Cochlear implant in the worse ear
Authors: Canale Andrea , Dalmasso Giulia , Dagna Federico , Lacilla Michelangelo , Montuschi Carla , Rosa Rosalba Di , Albera Roberto 
Published: November 2015

Objectives/HypothesisTo determine whether speech recognition scores (SRS) differ between adults with long‐term auditory deprivation in the implanted ear and adults who received cochlear implant (CI) in the nonsound‐deprived ear, either for hearing aid–assisted or due to rapidly deteriorating hearing loss.Study DesignRetrospective study.MethodsSpeech recognition scores at evaluations (3 and 14 months postimplantation) conducted with CI alone at 60‐dB sound pressure level intensity were compared in 15 patients (4 with bilateral severe hearing loss; 11 with asymmetric hearing loss, 7 of which had contralateral hearing aid), all with long‐term auditory deprivation (mean duration 16.9 years) (group A), and in 15 other patients with postlingual hearing loss (10 symmetric, 5 asymmetric with bimodal stimulation) (controls, group B).ResultsComparison of mean percentage of correctly recognized words on speech audiometry at 3 and 14 months showed improvement within each group (P < 0.05). Between‐group comparison showed no significant difference at 3 (P = 0.17) or 14 months (P = 0.46). Comparison of SRSs in group A (bimodal stimulation [n = 7] and binaural sound deprivation [n = 4]) versus group B showed no significant differences at 3 (bimodal stimulation P = 0.16; binaural sound deprivation P = 0.19) or 14 months (bimodal stimulation P = 0.14; binaural sound deprivation P = 0.82).ConclusionsSpeech recognition scores in monaural and binaural sound‐deprived ears did not significantly differ from ears with unilateral cochlear implantation in nonsound‐deprived ears when tested with CI alone. Improvement in the implanted worse ear indicates that it could be a potential candidate ear for cochlear implantation even when sound deprived.Level of Evidence4. Laryngoscope, 126:1905–1910, 2016
Synthesis and Properties of Side‐Chain Liquid Crystalline Polypeptides Bearing Various Alkyl Spacers and Oligo‐Ethylene‐Glycol Tails
Authors: Liu Dan , Yuan Qiulin , Ling Ying , Tang Haoyu 
Published: November 2015

A series of polypeptides bearing various alkyl (i.e., propyl, hexyl, or octyl) spacers, biphenyl mesogens, and oligo‐ethylene‐glycol (OEG) tails (i.e., PPLG26‐BPOEG
m, PHLG34‐BPOEGm, and POLG32‐BPOEGm [m = 3 or 7]) has been synthesized via 1,3‐dipolar cycloaddition reactions with quantitative grafting densities. Fourier transform infrared results reveal that the polypeptides adopted an α‐helical conformation in the solid‐state. Differential scanning calorimetry (DSC) analysis reveals that the glass transition temperatures (Tgs) of the polypeptides with OEG3 tails decrease with the increasing length of the alkyl spacers. For the samples containing alkyl spacers of the same length, Tg significantly decreases with the increasing lengths of the OEG tails. Polarized optical microscope (POM) results reveal that all polypeptides exhibit strong birefringence at room temperature. Polypeptides with long alkyl spacers (i.e., hexyl or octyl) or OEG7 tails show isotropic transitions, while PPLG26‐BPOEG3 show no clear point temperature before thermal decomposition. DSC, POM, and wide‐angle X‐ray scattering results collectively reveal that polypeptides with long alkyl spacers (i.e., hexyl or octyl) and OEG3 tails undergo a reversible smectic E phase to isotropic phase transition, while polypeptides with OEG7 tails undergo a reversible liquid crystalline phase to isotropic phase transition. The transition temperatures increase with the increasing length of alkyl spacers.
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Research on Hydrophobic and Superhydrophobic Properties of Patterned Structure with Controllable Nano to Microstructural Hierarchy
Authors: Huang Junjie , Wang Shuo , Sun Wei , Zhang Zhenzhen , Cheng Chuang , Ju Yuanlai , Yang Pinghui , Ding Lingyun , Chen Zhong‐Ren 
Published: November 2015

Presented here is a scalable self‐assembly route for fabricating a hierarchically structured material, possessing the property of superhydrophobicity, based on the breath figure (BF) method. The composite‐structured elastomers with dynamically controllable micro and nanoscale roughness are fabricated by stamping close‐packed monolayer of monodispersed silica particles, with different sizes, onto the surface of polydimethylsiloxane (PDMS) protrusion arrays, prepared by copying various molding BF films. The result of water contact angles (WCAs) measurement reveals that the variations in size features of either microscale or nanoscale make little difference in the WCAs of micropatterned or composite‐structured elastomers. It has been found out that the ratio of prominence pitch to protrusion diameter of structured PDMS samples keeps to be constant when the micro or nanoscale roughness varied a lot. The computation based on Cassie's law indicates that such geometrical feature contributes to the constant WCAs upon the varied roughness both in micro and nanoscale.
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Modeling and measurement of vesicle pools at the cone ribbon synapse: Changes in release probability are solely responsible for voltage‐dependent changes in release
Authors: Thoreson Wallace B. , Van hook Matthew J. , Parmelee Caitlyn , Curto Carina 
Published: November 2015

ABSTRACTPostsynaptic responses are a product of quantal amplitude (Q), size of the releasable vesicle pool (N), and release probability (P). Voltage‐dependent changes in presynaptic Ca2+ entry alter postsynaptic responses primarily by changing P but have also been shown to influence N. With simultaneous whole cell recordings from cone photoreceptors and horizontal cells in tiger salamander retinal slices, we measured N and P at cone ribbon synapses by using a train of depolarizing pulses to stimulate release and deplete the pool. We developed an analytical model that calculates the total pool size contributing to release under different stimulus conditions by taking into account the prior history of release and empirically determined properties of replenishment. The model provided a formula that calculates vesicle pool size from measurements of the initial postsynaptic response and limiting rate of release evoked by a train of pulses, the fraction of release sites available for replenishment, and the time constant for replenishment. Results of the model showed that weak and strong depolarizing stimuli evoked release with differing probabilities but the same size vesicle pool. Enhancing intraterminal Ca2+ spread by lowering Ca2+ buffering or applying BayK8644 did not increase PSCs evoked with strong test steps, showing there is a fixed upper limit to pool size. Together, these results suggest that light‐evoked changes in cone membrane potential alter synaptic release solely by changing release probability. Synapse 70:1–14, 2016. © 2015 Wiley Periodicals, Inc.