bluuebunny/crossref_metadata_2025_split huggingface dataset:
NiO–ZnO Nanoheterojunction Networks for Room‐Temperature Volatile Organic Compounds Sensing
Authors: Chen Hongjun , Bo Renheng , Shrestha Aabhash , Xin Bobo , Nasiri Noushin , Zhou Jin , Di Bernardo Iolanda , Dodd Aaron , Saunders Martin , Lipton‐Duffin Josh , White Thomas , Tsuzuki Takuya , Tricoli Antonio 
Published: September 2018

AbstractEngineering of highly performing nanomaterials, capable of rapid detection of trace concentrations of gas molecules at room temperature, is key to the development of the next generation of miniaturized chemical sensors. Here, a highly performing nanoheterojunctions layout is presented for the rapid room‐temperature chemical sensing of volatile organic compounds down to ten particles per billion concentrations. The layout consists of a 3D network of nickel oxide–zinc oxide (NiO–ZnO) p–n semiconductors with grain size of ≈20 nm nanometers and a porosity of ≈98%. Notably, it is observed that the formation of the p–n heterojunctions by decoration of a ZnO nanoparticle networks with NiO increases the sensor response by more than four times while improving the lower limit of detection. Under solar light irradiation, the optimal NiO–ZnO nanoheterojunction networks demonstrate a strong and selective room‐temperature response to two important volatile organic compounds utilized for breath analysis, namely acetone and ethanol. Furthermore, these NiO–ZnO nanoheterojunctions show an inverse response to acetone from that observed for all others reducing gas molecules (i.e., ethanol, propane, and ethylbenzene). It is believed that these novel insights of the optoelectrochemical properties of ultraporous nanoheterojunction networks provide guidelines for the future design of low‐power solid‐state chemical sensors.
Inverse‐Electron‐Demand [4+2]‐Cycloaddition of 1,3,5‐triazinanes: Facile Approaches to Tetrahydroquinazolines
Authors: Zheng Yongsheng , Tu Liang , Li Na , Huang Rong , Feng Tao , Sun Huan , Li Zhenghui , Liu Jikai 
Published: September 2018

AbstractAn unprecedented inverse‐electron‐demand [4+2] cycloaddition reaction of in situ generated aza‐o‐quinone methides with 1,3,5‐triazinanes has been developed under mild conditions, providing an efficient and mild approach to synthesize tetrahydroquinazolines in high yields (up to 99%) with excellent functional group tolerance. This protocol represents the first example of inverse‐electron‐demand [4+2] cycloaddition reaction of 1,3,5‐triazinanes.magnified image
Leaf adaptations and species boundaries in North AmericanCercis: implications for the evolution of dry floras
Authors: Fritsch Peter W. , Nowell Camille F. , Leatherman Lila S.T. , Gong Wei , Cruz Boni C. , Burge Dylan O. , Delgado‐Salinas Alfonso 
Published: September 2018

Premise of the StudyThe North AmericanCercisclade spans dry to mesic climates and exhibits complex morphological variation. We tested various proposed species classifications of this group and whether aspects of leaf morphology, particularly the “drip‐tip” in some regional populations, are adaptive and/or linked with phylogeny.MethodsWe made measurements on over 1100 herbarium specimens from throughout North America and analyzed the data with univariate and multivariate approaches. We analyzed phylogeneticallyDNAsequence data from nuclearITSand three plastid regions from 40 samples, and estimated divergence times with a relaxed‐clock Bayesian analysis. We used climate and geographic position data to predict the variation observed in leaf size and shape by using stepwise multiple linear regressions.Key ResultsMorphometric analyses yielded a pattern of continuous and often clinal character variation across North America, without correlated gaps in character states. Conversely, phylogenetic and divergence time analyses yielded distinct clades from California, the interior west, and eastern North America separated by between ~12 and 16 million years. Multiple regressions yielded highly significant correlations between leaf apex shape and precipitation of the warmest quarter.ConclusionsDespite a pattern of continuous morphological character variation, the long period of geographic and presumably genetic isolation warrants the delimitation of three species. Predictive modeling supports the adaptive value of acuminate apices or “drip‐tips” in mesic habitats. This suggests thatCercisleaves change more rapidly than inferred from parsimony reconstruction, which has implications for the evolution of the dry floras of North America and Eurasia.
The Effects of Multiple Dimensions of Risk and Protective Factors on Depressive Symptoms Among Nonresident African American Fathers
Authors: Tsuchiya Kazumi , Qian Yiqing , Thomas Alvin , Hill De Loney E. , Caldwell Cleopatra Howard 
Published: September 2018

AbstractCompared to other groups, African American men experience proportionately greater adverse social and economic circumstances, which have been linked to poor mental health. A growing body of literature has begun to examine depressive symptoms among African American men; however, limited literature has examined the concurrent contributions of risk and protective factors among nonresident African American fathers. This study examined the relative contribution of perceived financial strain, perceived neighborhood characteristics, and interpersonal stress on depressive symptoms among 347 nonresident African American fathers. Social support was examined as a protective factor for depressive symptoms. Results from hierarchical regression analyses indicated interpersonal stress was associated with depressive symptoms even after controlling for perceived financial strain, perceived neighborhood characteristics, and specific sociodemographic factors. Additionally, among fathers with high interpersonal stress, having more social support buffered the negative effect of interpersonal stress on depressive symptoms. Findings suggest experiencing strain from multiple dimensions can increase the risk of depressive symptoms among nonresident African American fathers. We also found that interpersonal stress was especially harmful for mental health. Family service providers and mental health professionals should incorporate stress management techniques to reduce stressful interpersonal relationships as a way to lower depressive symptoms among nonresident African American fathers.
Construction of Porous Mo3P/Mo Nanobelts as Catalysts for Efficient Water Splitting
Authors: Li Feng , Han Gao‐Feng , Noh Hyuk‐Jun , Lu Yalin , Xu Jiao , Bu Yunfei , Fu Zhengping , Baek Jong‐Beom 
Published: September 2018

AbstractA novel synthesis strategy is demonstrated to prepare Mo3P/Mo nanobelts with porous structure for the first time. The growth and formation mechanism of the porous Mo3P/Mo nanobelt structure was disclosed by varying the contents of H2/PH3 and the reaction temperature. During the hydrogen evolution reaction (HER) catalysis, the optimized porous Mo3P/Mo nanobelts exhibited a small overpotential of 78 mV at a current density of 10 mA cm−2 and a low Tafel slope of 43 mV dec−1, as well as long‐term stability in alkaline media, surpassing Pt wire. Density functional theory (DFT) calculations reveal that the H2O dissociation on the surface of Mo3P is favorable during the HER.
Breakdown of Curly Arrow Rules in Anthraquinone
Authors: Alqahtani Jehan , Sadeghi Hatef , Sangtarash Sara , Lambert Colin J. 
Published: September 2018

AbstractUnderstanding and controlling quantum interference (QI) in single molecules is fundamental to the development of QI‐based single‐molecule electronics. Simple rules such as counting rules, curly arrow rules (CARs), circuit rules, and more recently magic ratio rules have been developed to predict QI patterns in polycyclic aromatic hydrocarbons. CARs are widely used to predict destructive QI. Here we examine the validity of CARs in fully conjugated anthracene and dihydroxyanthracene, cross‐conjugated anthraquinone, and broken conjugated dihydroanthracene attached to either graphene or gold electrodes through π‐π stacking or thiol and Au−C anchors. For the first time, we demonstrate that CARs break down in molecular junctions formed by cross‐conjugated anthraquinone. In contrast with the destructive QI predicted by CARs for a meta‐connected anthraquinone core, we demonstrate that QI is constructive. This behavior is independent of the choice of electrode material or anchor groups. This is significant, because by changing the redox state of meta‐connected dihydroxyanthracene to form meta‐connected anthraquinone, the conductance of the junction increases by a couple of orders of magnitude due to the crossover from constructive to destructive QI. This opens new avenues for realization of QI‐based single‐molecule switches.
Helium Tagging of Protonated Methane in Messenger Spectroscopy: Does It Interfere with the Fluxionality of CH5+?
Authors: Uhl Felix , Marx Dominik 
Published: September 2018

AbstractMessenger infrared predissociation spectroscopy is an powerful technique to investigate elusive molecules. Despite accumulating evidence that 4He‐tagging has a minor effect on structure due to its weak interactions, its impact on intramolecular large‐amplitude motion is much less clear. Using one of the most floppy molecules known, protonated methane, we investigate to what extent helium tags perturb its salient fluxionality, underlying full hydrogen scrambling. Bosonic path integral quantum simulations show that the impact of attaching up to four 4He messengers to CH5+ is negligible compared to the non‐tagged bare species. This non‐invasive nature is unrelated to the bosonic character of 4He. Yet, hydrogen scrambling has a pronounced effect on the microsolvation shell pattern of CH5+⋅Hen that emerges as a result of tagging. These findings should provide impetus to explore the power of He‐tagging, particularly in the realm of weakly bound intermolecular complexes.
Facile synthesis of fluorinated poly(arylene ether nitrile) and its dielectric properties
Authors: Wei Junji , Meng Xiaojuan , Chen Xinyue , Bai Yafei , Song Jiale , Yan Ni , Zhu Lei , Shen Aiqin 
Published: September 2018

ABSTRACTA new class of specialty polymer, fluorinated poly(arylene ether nitrile) (PAEN‐F), was synthesized via the aromatic nucleophilic substitution reaction. Due to its rigid structure, PAEN‐F exhibited enhanced heat resistance and thermal stability. Consequently, the glass‐transition temperature and initial degradation temperature of PAEN‐F reached as high as 179°C and 554°C, respectively. PAEN‐F also showed excellent solubility in low‐boiling solvents owing to fluorine groups and the nonplanar structure in the repeat unit. Due to its strong 6F dipoles, PAEN‐F exhibited a high dielectric constant (ɛr) of 3.6, a high electrical breakdown strength of 346 MV/m, and a reasonably low dissipation factor (tan δ) of 0.014 at 25°C and 100 Hz. Therefore, this dipolar glass polymer is promising for high‐temperature and low‐loss electric energy storage applications. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018, 135, 46837.
Soluplus solutions as thermothickening materials for topical drug delivery
Authors: Salah I. , Shamat M. Abou , Cook M. T. 
Published: September 2018

ABSTRACTSoluplus is a pharmaceutical excipient used primarily in the manufacture of solid dispersions. The polymer also exhibits interesting rheology in aqueous solution, increasing in viscosity as the solution is warmed. This material could have application topical drug delivery to sites including the skin, vagina, rectum or nasal mucosa, where the increase in viscosity allows for improved retention. However, there exists very little information surrounding this “thermothickening” phenomenon and the effect of solution composition on temperature‐dependent rheology. In this study, the effect of soluplus concentration, salt inclusion, ethanol addition, and pH on temperature‐dependent rheology was measured. The rheology of the solutions was unaffected by pH over the range tolerated by the skin (pH 4–7), but the inclusion of ethanol rapidly negated the thermothickening effect. “Salting out” of the solutions resulted in a depression of gelation temperatures, and an increase in both storage and loss moduli of the solutions. 30% (w/v) soluplus in 1 M NaCl or KCl was identified as a potential thermothickening agent for topical drug delivery. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019, 136, 46915.
Diketopyrrolopyrrole tailoring charge transport characteristics of naphthalene diimide based polymers: From unipolar n‐typed to ambipolar polymers
Authors: Chen Zhi‐Cai , Fang Ren‐Ren , Yu Yuan‐Yuan , Gao Jian‐Hua , Wan Jun‐Hua 
Published: September 2018

ABSTRACTRandom copolymerization approach is confirmed to be an effective way to tailor the electronic structure and crystallinity of donor–acceptor copolymers. Diketopyrrolopyrroles (DPPs) as the second acceptor units with variable ratios were incorporated into naphthalene diimide (NDI)‐based polymers to obtained three low‐band‐gap random copolymers (P1–3). The low incorporation (10 and 30%) of DPP units did not substantially raise HOMO levels; thus, both P1 and P2 still exhibited unipolar n‐channel characteristics. When the incorporation of DPP increased to 50%, the major carries in organic field effect transistor (OFET) in P3 were switched from n‐channel to balanced ambipolar without sacrificing the electron mobility. However, P4, an alternating polymer of NDI and DPP with defined structure, exhibited unipolar n‐type transport characteristics because of the suppressed HOMO level. Polymer crystallinity and general macromolecular order have been studied carefully and discussed as it pertains to OFET performance. The present work thus highlights the structure–property relationship and the electronic tunability required in NDI‐based polymers to produce ambipolar transistors. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019, 136, 46926.
Thermal conductivity improvement in electrically insulating silicone rubber composites by the construction of hybrid three‐dimensional filler networks with boron nitride and carbon nanotubes
Authors: Xue Yang , Li Xiaofei , Wang Haosheng , Zhang Donghai , Chen Yunfa 
Published: September 2018

AbstractIn this study, we constructed hybrid three‐dimensional (3D) filler networks by simply incorporating a relatively low content of one‐dimensional carbon nanotubes (CNTs; 0.0005–0.25 vol %) and a certain content of two‐dimensional boron nitride (BN; 30 phr) in a silicone rubber (SIR) matrix. As indicated by transmission electron microscopy observation, flexible CNTs can serve as bridges to connect BN platelets in different layers to form hybrid 3D thermally conductive networks; this results in an increase in thermally conductive pathways, and the isolation between CNTs can prevent the formation of electrically conductive networks. Compared to the SIR–BN composite with the same BN content, the SIR–BN–CNT composites exhibited improved thermal conductivity, slightly increased volume resistivity, and comparable breakdown strength without a largely decreased flexibility. When 0.25 vol % CNTs were incorporated, the SIR–BN–CNT composite exhibited 75 and 25% higher thermal conductivities relative to the neat SIR and SIR–BN composite with 30 phr BN, respectively, and a thermal conductivity that was even comparable to SIR–BN composite with 40 phr BN. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci.2019,136, 46929.
Rhodium‐Catalyzed Domino Hydroformylation/Double‐Cyclization Reaction of Arylacetylenecarboxamides: Diastereoselectivity Studies and Application in the Synthesis of 1‐Azabicyclo[x.y.0]alkanes
Authors: Tsai Jui‐Chi , Lin Yi‐Huei , Chen Guei‐Tang , Gao Yu‐Kai , Tseng Yu‐Che , Kao Chien‐Lun , Chiou Wen‐Hua 
Published: September 2018

AbstractA domino method for the rapid syntheses of 1‐azabicyclo[x.y.0]alkane scaffolds, such as indolizidines, quinolizidines, decahydropyridoazepines, and their derivatives, has been developed. This strategy involved a rhodium‐catalyzed hydroformylation of allyl‐, 3‐butenyl‐, or homoallyl amides, followed by two spontaneous ring closures under mild conditions. The reaction scope and diastereoselectivity were fully explored by changing the substitution pattern on the amide and by altering the length of the carbon chain. This method was applied to the syntheses of natural alkaloids tashiromine and epilupinine. The clear differences between the reactivities of two isomeric amide substrates, 3‐butenamide 1 j and homoallyl amide 1 i, could be attributed to better HOMO–LUMO overlap in the transition states that were derived from butenamides during cyclization. This explanation was supported by DFT calculations.
Bayesian network for risk‐informed inspection planning in ships
Authors: Kim Hyun‐Joong , Hamann Rainer , Sotiralis Panagiotis , Ventikos Nikolaos P. , Straub Daniel 
Published: September 2018

AbstractWe present the development of a Bayesian Network (BN) model for risk assessment of ships to facilitate risk‐informed inspection planning. The BN consists of four sub‐modules: cause, vulnerability, consequence and inspection. These modules are set up in a generic manner by consideration of readily available information (the indicators), such as ship type, ship size, operational conditions. On this basis, we define representative models of the ship and its components, which are parameterized by the indicators and quantities that can be related to the indicators. The generic approach enables a fast and holistic risk assessment of a larger number of ships even if only limited information is available. The BN approach facilitates the straightforward inclusion of new information, e.g. from inspection and monitoring. It has the additional advantage of allowing easier communication of the model to non‐experts. Through numerical applications, we demonstrate how the calculated risks can be used to prioritize inspections and how new information can be incorporated to update risk estimates.
Calibrating safety factors for Carbon Concrete
Authors: Weselek Jörg , Häußler‐Combe Ulrich 
Published: September 2018

AbstractSafety factors are a decisive topic within the framework of a semi‐probabilistic safety concept as is common practice in civil engineering. Long‐time experience is not available for new, innovative reinforcing materials like carbon concrete. Therefore the current paper outlines an approach involving level‐II reliability methods for a comparison of its results with those of a deterministic calculation approach using partial safety factors. The aim is an economical calibration of the material specific factor for carbon concrete. Afterwards an evaluation of the result's quality is performed by the adoption of more precise level‐III reliability methods on specific scenarios. A major subject is the pre‐set value of the FORM sensitivity factor αR in the valid calibration procedure according to [1].
BMI trajectories and risk of overall and grade‐specific prostate cancer: An observational cohort study among men seen for prostatic conditions
Authors: Wang Kai , Chen Xinguang , Gerke Travis A. , Bird Victoria Y. , Ghayee Hans K. , Prosperi Mattia 
Published: September 2018

AbstractBackgroundDynamic longitudinal patterns in body mass index (BMI) have been suggested to better predict health outcomes than static measures. Effects of BMI trajectories on prostate cancer (PCa) risk have not been thoroughly explored.MethodsCohort data were derived from electronic medical records of patients who were admitted to a tertiary‐care hospital in the Southeastern USA during 1994‐2016. Patients with a history of urologic clinic visit because of any prostatic condition and with repeatedly measured BMI (n = 4857) were included. BMI trajectories prior to PCa diagnosis were assessed using the developmental trajectory analysis method. Cox proportional hazards regression modeling was used to estimate adjusted hazard ratio (aHR) with 95% confidence intervals (CIs) for overall and grade‐specific PCa.ResultsThe median age (interquartile range, IQR) of the participants at baseline was 63 (54, 72) years. Over a median follow‐up (IQR) of 8.0 (2.0, 13.0) years, 714 (14.7%, 714/4857) were diagnosed with PCa. Men with growing BMI trajectory progressing from normal weight to overweight/obese had a 76% increased PCa risk (aHR = 1.76; 95% CI: 1.25, 2.48), and men being obese and experiencing progressive weight gain had 3.72‐fold increased PCa risk (aHR = 3.72; 95% CI: 1.60, 8.66), compared to men with persistently normal BMI. The associations were more pronounced for PCa with Gleason score ≥7. No significant association of decreasing BMI trajectory progressing from obese to normal BMI was found with PCa risk.ConclusionsProgressively body weight gain during middle‐to‐late adulthood was associated with increased PCa risk for both normal weight and overweight men. Further studies are warranted to confirm this finding.
Acute myocardial infarction secondary to blunt chest trauma in motorcycle accident: A rare combination where percutaneous coronary intervention and intravascular imaging optimization are needed
Authors: Boi Alberto , Sanna Francesco , Rossi Angelica , Loi Bruno 
Published: September 2018

AbstractBlunt chest trauma is a common occurrence in vehicle accident. Cardiac injuries following nonpenetrating thoracic trauma have been reported. ST‐elevation myocardial infarction (STEMI) due to coronary artery involvement is a rare but extremely serious condition for the high risk of undetected diagnosis. Blunt thoracic trauma may obscure typical chest pain associated with cardiac ischemia especially in patients with high tolerance of pain or secondary administration of analgesic drugs. We report two consecutive cases of young adults admitted to our emergency department after motorcycle accident and concomitant anterior STEMI due to occlusion of left anterior descending artery. In both cases primary percutaneous coronary intervention with a second generation drug eluting stent implantation was successfully performed. Imaging with intravascular ultrasound and optical coherence tomography showed the mechanisms of coronary occlusion, allowing an optimal stent implantation and avoiding procedural complications in this complex setting.
Electrochemical Degradation of Piroxicam on a Boron‐Doped Diamond Anode: Investigation of Operating Parameters and Ultrasound Synergy
Authors: Kouskouki Aikaterini , Chatzisymeon Efthalia , Mantzavinos Dionissios , Frontistis Zacharias 
Published: September 2018

AbstractThe electrochemical oxidation of piroxicam (PIR), a representative nonsteroidal anti‐inflammatory drug, was studied using boron‐doped diamond (BDD) as anode. BDD exhibited superior efficiency in comparison with platinum electrodes in terms of PIR degradation. Removal of PIR follows pseudo‐first‐order kinetics and the apparent kinetic constants decreased from 0.138 to 0.0369 min−1 as the initial PIR concentration increased from 245 to 975 μg L−1. Altering of the pH had little effect on electrolysis of PIR with slightly better removal at pH 9. The presence of 10 g L−1 of tert‐butanol inhibited PIR removal, indicating that its oxidation is caused by electro‐generated hydroxyl radicals. Addition of 200 mg L−1 sodium chloride increased the apparent kinetic constant more than ten times from 0.139 to 1.44 min−1. Similar behavior was observed in the case of bicarbonates and nitrates, possibly due to the generation of selective carbonate radicals and active oxygen species like nitric or nitrous oxides. Experiments were also conducted in various aqueous matrices and it was observed that the presence of humic acid delayed the degradation of PIR, while process efficiency was enhanced in bottled and surface water as well as in wastewater, due to the presence of inorganic ions. Coupling BDD electrolysis with ultrasound (at 14 W L−1, 20 kHz) increased the reaction rate of PIR destruction and the observed synergy was calculated at S=44.6 %.