bluuebunny/crossref_metadata_2025 huggingface dataset:
Simultaneous determination of tryptophan, kynurenine, kynurenic acid, xanthurenic acid and 5‐hydroxytryptamine in human plasma by LC‐MS/MS and its application to acute myocardial infarction monitoring
Authors: Tong Qing , Song Jia , Yang Guangjie , Fan Li , Xiong Wei , Fang Jianguo
Published: November 2017

Reliable methods for the determination of tryptophan and its metabolites are vital to the monitoring of biochemical states during the initiation and progression of cardiovascular disease. In the present study, a single‐run liquid chromatography–tandem mass spectrometry (LC‐MS/MS) method was developed for the simultaneous determination of tryptophan (Trp) and its metabolites, including kynurenine (Kyn), kynurenic acid (KA), xanthurenic acid (XA) and 5‐hydroxytryptamine (5‐HT), in human plasma. The plasma samples were prepared using a protein precipitation approach, and the chromatographic separation was performed by gradient elution on a C18 column within a total analysis time of 3.5 min. The calibration ranges were 40–20,000 ng/mL for Trp, 4–2000 ng/mL for Kyn, 0.2–100 ng/mL for KA, 0.4–200 ng/mL for XA and 1–500 ng/mL for 5‐HT, and the precision and accuracy were acceptable. The evaluation of recovery and internal standard‐normalized matrix effect proved that the sample preparation approach was effective and the matrix effect could be negligible. The newly developed method was successfully applied to the analysis of plasma samples from healthy individuals and myocardial infarction patients. The findings suggested that the plasma concentrations of Trp, Kyn, 5‐HT as well as the concentration ratios of Kyn/Trp and Trp/5‐HT might serve as biomarkers for the monitoring of acute myocardial infarction.
Development and validation of an LC‐MS/MS method for the determination of a novel thienoquinolin urea transporter inhibitor PU‐48 in rat plasma and its application to a pharmacokinetic study
Authors: Zhang Zhi‐Yuan , Wang Xin , Liu Dan , Zhang Hua , Zhang Qiang , Lu Ying‐Yuan , Li Pu , Lou Ya‐Qing , Yang Bao‐Xue , Lu Chuang , Lou Ya‐Xin , Zhang Guo‐Liang
Published: November 2017

A specific, sensitive and stable high‐performance liquid chromatographic–tandem mass spectrometry (LC‐MS/MS) method was developed and validated for the quantitative determination of methyl 3‐amino‐6‐methoxythieno [2,3‐b]quinoline‐2‐carboxylate (PU‐48), a novel diuretic thienoquinolin urea transporter inhibitor in rat plasma. In this method, the chromatographic separation of PU‐48 was achieved with a reversed‐phase C18 column (100 × 2.1 mm, 3 μm) at 35°C. The mobile phase consisted of acetonitrile and water with 0.05% formic acid added with a gradient elution at flow rate of 0.3 mL/min. Samples were detected with the triple‐quadrupole tandem mass spectrometer with multiple reaction monitoring mode via electrospray ionization source in positive mode. The retention time were 6.2 min for PU‐48 and 7.2 min for megestrol acetate (internal standard, IS). The monitored ion transitions were mass‐to‐charge ratio (m/z) 289.1 → 229.2 for PU‐48 and m/z 385.3 → 267.1 for the internal standard. The calibration curve for PU‐48 was linear over the concentration range of 0.1–1000 ng/mL (r2 > 0.99), and the lower limit of quantitation was 0.1 ng/mL. The precision, accuracy and stability of the method were validated adequately. The developed and validated method was successfully applied to the pharmacokinetic study of PU‐48 in rats.
From Ruthenium to Iron and Manganese—A Mechanistic View on Challenges and Design Principles of Base‐Metal Hydrogenation Catalysts
Authors: Zell Thomas , Langer Robert
Published: November 2017

The development of new homogenous base‐metal catalysts for hydrogenation reactions is a rapidly expanding and evolving field of research, which has the potential to provide inexpensive and sustainable alternatives for atom economic reactions and possibly contribute additional tools for hydrogen storage applications. While tremendous accomplishments in terms of catalytic activity and substrate scope have been reported over the last years, the available mechanistic information on these reactions is often very limited. The current Concept article intends to summarize, categorize and analyze mechanistic information on iron‐based hydrogenation catalysts. In addition, we present the challenges that must be tackled in the future to develop more effective and mature catalyst systems. The primary focus of this work lies on iron‐based catalysts. However, manganese‐based hydrogenation catalysts have recently attracted significant interest and a remarkable progress in their development has been made. Available mechanistic information on manganese catalysts is compared to that on iron catalysts and basic similarities and differences are discussed.
Electrogenerated N‐Heterocyclic Olefins: Stability and Catalytic Ability
Authors: Feroci Marta , Chiarotto Isabella , Orsini Monica , Pandolfi Fabiana , Zane Daniela , Inesi Achille
Published: November 2017

N‐Heterocyclic olefin (NHO) can be generated by simple cathodic reduction of BDMImBF4‐DMF solution or neat BDMImBF4 (BDMImBF4=1‐butyl‐2,3‐dimethyl‐1H‐imidazolium tetrafluoroborate; DMF=dimethylformamide). In the latter case, the use of any organic solvent and chemical base is avoided. To prove the presence of NHO, its adduct with benzaldehyde was isolated. The electrochemical behavior of NHO is very similar to that of the corresponding N‐heterocyclic carbene (NHC, from 1‐butyl‐3‐methyl‐1H‐imidazolium tetrafluoroborate), showing that it is electroactive at the anode, and this peculiarity can be exploited to verify its presence in a solution. The main difference between NHO and NHC is in the nucleophilic site (exocyclic for NHO, endocyclic for NHC). Electrogenerated NHO stability (evaluated by cyclic voltammetry) and its catalytic ability (evaluated in the transesterification reaction) were compared with those of electrogenerated NHC.
An Omni‐healable and Tailorable Aqueous Lithium‐Ion Battery
Authors: Hao Zhaohan , Tao Feng , Wang Zhikui , Cui Ximing , Pan Qinmin
Published: November 2017

Reliability and safety are critical issues for portable power sources aiming for next‐generation electronics. However, most lithium‐ion batteries (LIBs) will fail to work or will cause safety problems after physical damage or violent deformation. Here, an omni‐healable aqueous LIB, which can self‐repair its electrodes and electrolyte simultaneously after mechanical breakage, is fabricated by integrating all of the electroactive components into polymer networks cross‐linked by dynamic borate ester bonding. Once suffering from repeated cutoffs, the battery quickly recovers its configuration integrity as well as mechanical and electrochemical properties autonomously without external stimuli. Furthermore, the battery can also be tailored into complicated patterns while maintaining its lithium‐storage properties. The present investigation offers a strategy to design a smart and sustainable energy‐storage device that has potential applications in wearable/flexible electronics, flexible robot or intelligent apparel, and so on.
Characterization at the Level of Individual Crystals: Single‐Crystal MFI Type Zeolite Grains
Authors: Gruene Tim , Li Teng , van Genderen Eric , Pinar Ana B. , van Bokhoven Jeroen A.
Published: November 2017

Electron‐diffraction data on the zeolites Silicalite‐1 and ZSM‐5 (both MFI framework type) were collected from individual grains of about 150×100×50 nm3. Crystals were synthesized with tetrapropylammonium as structure‐directing agent. The resolution extended to about 0.8 Å for Silicalite‐1 and about 0.9–1.0 Å for ZSM‐5 crystals. Analysis of several data sets showed that at the nanometre‐scale, these zeolite crystals are single crystals and not intergrown.
On the Structure and Reaction Mechanism of Human Acireductone Dioxygenase
Authors: Miłaczewska Anna , Kot Ewa , Amaya José A. , Makris Thomas M. , Zając Marcin , Korecki Józef , Chumakov Aleksandr , Trzewik Bartosz , Kędracka‐Krok Sylwia , Minor Władek , Chruszcz Maksymilian , Borowski Tomasz
Published: November 2017

Acireductone dioxygenase (ARD) is an intriguing enzyme from the methionine salvage pathway that is capable of catalysing two different oxidation reactions with the same substrate depending on the type of the metal ion in the active site. To date, the structural information regarding the ARD–acireductone complex is limited and possible reaction mechanisms are still under debate. The results of joint experimental and computational studies undertaken to advance knowledge about ARD are reported. The crystal structure of an ARD from Homo sapiens was determined with selenomethionine. EPR spectroscopy suggested that binding acireductone triggers one protein residue to dissociate from Fe2+, which allows NO (and presumably O2) to bind directly to the metal. Mössbauer spectroscopic data (interpreted with the aid of DFT calculations) was consistent with bidentate binding of acireductone to Fe2+ and concomitant dissociation of His88 from the metal. Major features of Fe vibrational spectra obtained for the native enzyme and upon addition of acireductone were reproduced by QM/MM calculations for the proposed models. A computational (QM/MM) study of the reaction mechanisms suggests that Fe2+ promotes O−O bond homolysis, which elicits cleavage of the C1−C2 bond of the substrate. Higher M3+/M2+ redox potentials of other divalent metals do not support this pathway, and instead the reaction proceeds similarly to the key reaction step in the quercetin 2,3‐dioxygenase mechanism.
Tunability of Open‐Shell Character, Charge Asymmetry, and Third‐Order Nonlinear Optical Properties of Covalently Linked (Hetero)Phenalenyl Dimers
Authors: Minamida Yuka , Kishi Ryohei , Fukuda Kotaro , Matsui Hiroshi , Takamuku Shota , Yamane Masaki , Tonami Takayoshi , Nakano Masayoshi
Published: November 2017

Tunability of the open‐shell character, charge asymmetry, and third‐order nonlinear optical (NLO) properties of covalently linked (hetero)phenalenyl dimers are investigated by using the density functional theory method. By changing the molecular species X and substitution position (i, j) for the linker part, a variety of intermonomer distances R and relative alignments between the phenalenyl dimers can be realized from the geometry optimizations, resulting in a wide‐range tuning of diradical character y and charge asymmetry. It is found that the static second hyperpolarizabilities along the stacking direction, γyyyy, are one‐order enhanced for phenalenyl dimer systems exhibiting intermediate y, a feature that is in good agreement with the “y–γ correlation”. By replacing the central carbon atoms of the phenalenyl rings with a boron or a nitrogen, we have also designed covalently linked heterophenalenyl dimers. The introduction of such a charge asymmetry to the open‐shell systems, which leads to closed‐shell ionic ground states, is found to further enhance the γyyyy values of the systems having longer intermonomer distance R with intermediate ionic character, that is, charge asymmetry. The present results demonstrate a promising potential of covalently linked NLO dimers with intermediate open‐shell/ionic characters as a new building block of highly efficient NLO systems.
Humidity‐Responsive ON/OFF Switching of Gas Inclusion by Using Cooperative Opening/Closing of Heterogeneous Crystalline Cavities in a Peptide NiII Macrocycle
Authors: Miyake Ryosuke , Kuwata Chika , Ueno Manami , Yamada Teppei
Published: November 2017

Humidity‐responsive ON/OFF switching of CO2 inclusion, associated with cooperative structural changes of heterogeneous cavities in crystalline peptide NiII macrocycles, 1⋅NO3, is demonstrated. The structural transformation between an “open form” and a “closed form” was caused by reversible water uptake into one of the cavities. The adsorption behavior of CO2 was studied with and without water vapor, combined with gas‐composition analysis by using gas chromatography. The studies revealed that the open form of 1⋅NO3 adsorbs CO2 gas up to 34 g mol−1, whereas the closed form adsorbs only a negligible amount of CO2 gas. Also, structural studies (X‐ray and IR spectroscopies) and investigation of water‐content dependence of CO2 adsorption revealed that the switching of gas inclusion occurred abruptly over a narrow range of water‐vapor pressure and was caused by the cooperative opening of vacant space to give the open form due to the structural transformation by water uptake.
Solid‐State Structure of Tris‐Cyclopentadienide Uranium(III) and Plutonium(III)
Authors: Apostolidis Christos , Dutkiewicz Michał S. , Kovács Attila , Walter Olaf
Published: November 2017

The organometallic tris‐cyclopentadienide actinide(III) (AnCp3) complexes were first reported about 50 years ago. However, up until now, only the NpCp3 solid state structure has been studied. Here we report on the solid state structures of UCp3 and PuCp3 which are isostructural to the Np analogue. The structural models are supported by theoretical calculations and compared to their lanthanide analogues. The observed trends in changes of bond lengths might be indicator for an increased covalency in the bonding in the tris‐cyclopentadienide actinide(III) complexes (AnCp3) compared to their lanthanide homologues.
A Redox‐Active Bis(ferrocenyl)germylene and Its Reactivity
Authors: Suzuki Yuko , Sasamori Takahiro , Guo Jing‐Dong , Tokitoh Norihiro
Published: November 2017

Bis(ferrocenyl)germylene Fc*2Ge: [2; Fc*=2,5‐bis(3,5‐di‐tert‐butylphenyl)‐1‐ferrocenyl] was isolated in the form of red crystals from the reaction of the sterically demanding ferrocenyl lithium dimer (Fc*Li)2 and GeI2. Bis(ferrocenyl)germylene 2 exhibits extraordinary thermal stability in hydrocarbon solution and the solid state, as well as stable redox behavior. Moreover, it undergoes a ligand‐redistribution reaction with GeCl2⋅(dioxane) to afford the corresponding chlorogermylene, which was isolated upon coordination with PBu3.
Single‐Dose Bioequivalence of Two Mini Nicotine Lozenge Formulations
Authors: Rasmussen Scott C. , Becker William D. , Shanga Gilbert M.
Published: November 2017

Diverse nicotine replacement therapy options may improve consumer usage. This study was conducted to establish the bioequivalence of a new cherry‐flavored mini lozenge with that of a currently marketed mint‐flavored mini lozenge. The rate (Cmax) and extent (AUC0–t) of plasma nicotine absorption were compared after administration of 2‐ and 4‐mg doses of each lozenge in healthy adult smokers (n = 43). The bioequivalence of each respective dose was established based on the 90% confidence interval for the ratio of geometric means for both Cmax and AUC0–t lying within the range of 0.80 to 1.25. Adverse‐event profiles were similar between formulations.
Artificial Photosynthesis: Learning from Nature
Authors: Whang Dong Ryeol , Apaydin Dogukan Hazar
Published: November 2017

Artificial photosynthesis has been devised and investigated in pursuit of solving the 21st century's energy problem. Despite significant advances in recent decades, applying the technology in real life is still a challenging subject for scientists. As the term “artificial photosynthesis” stems from mimicking natural photosynthesis, we can learn from nature's strategies which have evolved over 3.4 billion years. This Review highlights important strategies of natural photosynthesis which can be borrowed for highly efficient and robust artificial photosystems for solar fuel production. Starting with a brief description of photosystem II in natural photosynthetic autotrophs, three relevant bioinspired strategies are discussed in this article: i) accumulative charge transfer, ii) photoprotection, and iii) self‐healing. Next, development of artificial photosystems mimicking those strategies will be discussed. Finally, remaining challenges and perspectives for future development of artificial photosynthesis are described.
Bismuth Vanadate Photoelectrodes with High Photovoltage as Photoanode and Photocathode in Photoelectrochemical Cells for Water Splitting
Authors: dos Santos Wayler S. , Rodriguez Mariandry , Khoury Júlia M. O. , Nascimento Luíza A. , Ribeiro Rebecca J. P. , Mesquita João P. , Silva Adilson C. , Nogueira Francisco G. E. , Pereira Márcio C.
Published: November 2017

Using dual‐photoelectrode photoelectrochemical (PEC) devices based on earth‐abundant metal oxides for unbiased water splitting is an attractive means of producing green H2 fuel, but is challenging, owing to low photovoltages generated by PEC cells. This problem can be solved by coupling n‐type BiVO4 with n‐type Bi4V2O11 to create a virtual p/n junction due to the formation of a hole‐inversion layer at the semiconductor interface. Thus, photoelectrodes with high photovoltage outputs were synthesized. The photoelectrodes exhibited features of p‐ and n‐type semiconductors when illuminated under an applied bias, suggesting their use as photoanode and photocathode in a dual‐photoelectrode PEC cell. This concept was proved by connecting a 1 mol % W‐doped BiVO4/Bi4V2O11 photoanode with an undoped BiVO4/Bi4V2O11 photocathode, which produced a high photovoltage of 1.54 V, sufficient to drive stand‐alone water splitting with 0.95 % efficiency.
Dispersion of kinetic Alfvén wave in a rotating plasma with an inhomogeneous magnetic field
Authors: Liu Y. , Teng Y.
Published: November 2017

The effects of inhomogeneity of a magnetic field on the dispersion of kinetic Alfvén waves (KAWs) in a rotating plasma is investigated under the framework of magnetohydrodynamic theory. The magnetic field should be in a non‐uniform state if the centrifugal force is balanced only by the magnetic pressure. The inhomogeneity of the magnetic field increases the frequency of KAW and drives it into an unstable state. The growth rate of KAW varies non‐monotonously with respect to the distance. The KAW will be excited in a certain region with maximum growth rate. And the growth rate of KAW in the region near and far from the centre of rotation approaches zero. These results will be helpful in understanding the properties of KAWs in rotating astrophysical and laboratory plasmas.
On the mobile‐to‐mobile linear time‐variant shallow‐water acoustic channel response
Authors: Sauco‐Gallardo Adrián , Fernández‐Plazaola Unai , Díez Luis
Published: November 2017

We expose some concepts concerning the channel impulse response (CIR) of linear time‐varying (LTV) channels to give a proper characterization of the mobile‐to‐mobile underwater channel. We find different connections between the linear time‐invariant (LTI) CIR of the static channel and 2 definitions of LTV CIRs of the dynamic mobile‐to‐mobile channel. These connections are useful to design a dynamic channel simulator from the static channel models available in the literature. Such feature is particularly interesting for overspread channels, which are hard to characterize by a measuring campaign. Specifically, the shallow water acoustic (SWA) channel is potentially overspread because of the signal low velocity of propagation, which prompts long delay spread responses and great Doppler effect. Furthermore, from these connections between the LTI static CIRs and the LTV dynamic CIRs, we find that the SWA mobile‐to‐mobile CIR does not only depend on the relative speed between transceivers, but also on the absolute speed of each of them referred to the velocity of propagation. Nevertheless, publications about this topic do not consider it and formulate their equations in terms of the relative speed between transceivers. We illustrate our find using 2 couples of examples where, even though the relative speed between the mobiles is the same, their CIRs are not.
Does noninvasive follicular thyroid neoplasm with papillary‐like nuclear features have distinctive features on sonography?
Authors: Brandler Tamar C. , Yee Joseph , Zhou Fang , Cho Margaret , Cangiarella Joan , Wei Xiao‐Jun , Yee‐Chang Melissa , Sun Wei
Published: November 2017

Background

The noninvasive encapsulated follicular variant of papillary carcinoma (nEFVPTC) has recently been reclassified to “noninvasive follicular thyroid neoplasm with papillary‐like nuclear features (NIFTP),” removing this entity from the malignant category. This re‐categorization has had major implications for clinical management. NIFTP has overlapping cytohistologic features with papillary thyroid carcinoma (PTC) and with follicular adenomas (FA), but sonographic data comparing NIFTP to PTC and FA is lacking. Our study examines the sonographic features of NIFTP as compared with PTC and FA.

Methods

Ultrasound scans and Doppler blood flow from subjects who had pre‐surgical sonograms and fine needle aspiration biopsies with final surgical pathology diagnoses of NIFTP/nEFVPTC, classical PTC, and FA between 01/2013‐08/2016 were assessed. Sonographic and Doppler features as well as Bethesda System (TBS) diagnoses were recorded and analyzed.

Results

40 NIFTP, 58 classical PTC, and 23 FA cases were included. The most common NIFTP pre‐surgical TBS cytology diagnosis was Atypia of Undetermined Significance (AUS/FLUS) (40%). NIFTP cases predominantly displayed wider‐than‐tall shape (100%), smooth borders (75%), occurrence in multinodular glands (82.5%), heterogeneous echogenicity (50%), both perinodular and intranodular Doppler flow patterns (70%), minimal Doppler flow grade (62.5%), and no calcifications (90%).

Conclusions

Our study demonstrates that NIFTP, PTC, and FA display several distinguishing and overlapping sonographic and Doppler features. Sonographic features appear to complement cytology findings and may help raise pre‐operative concern for NIFTP in the proper clinical setting, potentially leading to a more conservative management approach.
Tuberculosis in Pap samples with emphasis on LBC: Caught only when thought
Authors: Bharani Vani , Gupta Nalini , Suri Vanita , Rajwanshi Arvind
Published: November 2017

Despite being a commonly encountered infection, the clinical diagnosis of tuberculosis of the uterine cervix is elusive. Though a straightforward diagnosis on tissue sections, identification of typical features of tubercular infection on cervical Pap samples is challenging. In our experience, the infrequent pale staining collections of epithelioid cells are difficult to pick up on Pap stained smears, particularly LBC samples. In this series, 2 of the three samples were reported as atypical squamous cells of undetermined significance while 1 was reported as inflammatory at the initial diagnosis. Scattered Langhans' type giant cells may be seen as a subtle clue which should prompt the search for epithelioid cell granulomas. These cases may have a mass lesion clinically while no obvious signs of malignancy on the cervical samples.
Ankle muscle tenotomy does not alter ankle flexor muscle recruitment bias during locomotor‐related repetitive limb movement in late‐stage chick embryos
Authors: Sun Soo Yeon , Baker Lucinda L. , Bradley Nina S.
Published: November 2017

In ovo, late‐stage chick embryos repetitively step spontaneously, a locomotor‐related behavior also identified as repetitive limb movement (RLM). During RLMs, there is a flexor bias in recruitment and drive of leg muscle activity. The flexor biased activity occurs as embryos assume an extremely flexed posture in a spatially restrictive environment 2–3 days before hatching. We hypothesized that muscle afferent feedback under normal mechanical constraint is a significant input to the flexor bias observed during RLMs on embryonic day (E) 20. To test this hypothesis, muscle afference was altered either by performing a tenotomy of ankle muscles or removing the shell wall restricting leg movement at E20. Results indicated that neither ankle muscle tenotomy nor unilateral release of limb constraint by shell removal altered parameters indicative of flexor bias. We conclude that ankle muscle afference is not essential to ankle flexor bias characteristic of RLMs under normal postural conditions at E20.
Leaf trait variations associated with habitat affinity of tropical karst tree species
Authors: Geekiyanage Nalaka , Goodale Uromi Manage , Cao Kunfang , Kitajima Kaoru
Published: November 2017

Karst hills, that is, jagged topography created by dissolution of limestone and other soluble rocks, are distributed extensively in tropical forest regions, including southern parts of China. They are characterized by a sharp mosaic of water and nutrient availability, from exposed hilltops with poor soil development to valleys with occasional flooding, to which trees show species‐specific distributions. Here we report the relationship of leaf functional traits to habitat preference of tropical karst trees. We described leaf traits of 19 tropical tree species in a seasonal karst rainforest in Guangxi Province, China, 12 species in situ and 13 ex situ in a non‐karst arboretum, which served as a common garden, with six species sampled in both. We examined how the measured leaf traits differed in relation to species’ habitat affinity and evaluated trait consistency between natural habitats vs. the arboretum. Leaf mass per area (LMA) and optical traits (light absorption and reflectance characteristics between 400 and 1,050 nm) showed significant associations with each other and habitats, with hilltop species showing high values of LMA and low values of photochemical reflectance index (PRI). For the six species sampled in both the karst forest and the arboretum, LMA, leaf dry matter content, stomatal density, and vein length per area showed inconsistent within‐species variations, whereas some traits (stomatal pore index and lamina thickness) were similar between the two sites. In conclusion, trees specialized in exposed karst hilltops with little soils are characterized by thick leaves with high tissue density indicative of conservative resources use, and this trait syndrome could potentially be sensed remotely with PRI.
Effects of social information on life history and mating tactics of males in the orb‐web spider Argiope bruennichi
Authors: Cory Anna‐Lena , Schneider Jutta M.
Published: November 2017

Informed mating decisions are often based on social cues providing information about prospective mating opportunities. Social information early in life can trigger developmental modifications and influence later mating decisions. A high adaptive value of such adjustments is particularly obvious in systems where potential mating rates are extremely limited and have to be carried out in a short time window. Males of the sexually cannibalistic spider Argiope bruennichi can achieve maximally two copulations which they can use for one (monogyny) or two females (bigyny). The choice between these male mating tactics should rely on female availability that males might assess through volatile sex pheromones emitted by virgin females. We predict that in response to those female cues, males of A. bruennichi should mature earlier and at a smaller body size and favor a bigynous mating tactic in comparison with controls. We sampled spiders from two areas close to the Southern and Northern species range to account for differences in mate quality and seasonality. In a fully factorial design, half of the subadult males from both areas obtained silk cues of females, while the other half remained without female exposure. Adult males were subjected to no‐choice mating tests and could either monopolize the female or leave her (bigyny). We found that Southern males matured later and at a larger size than Northern males. Regardless of their origin, males also shortened the subadult stage in response to female cues, which, however, had no effects on male body mass. Contrary to our prediction, the frequencies of mating tactics were unaffected by the treatment. We conclude that while social cues during late development elicit adaptive life history adjustments, they are less important for the adjustment of mating decisions. We suggest that male tactics mostly rely on local information at the time of mate search.
Does transpiration from invasive stream side willows dominate low‐flow conditions? An investigation using hydrometric and isotopic methods in a headwater catchment
Authors: Marttila H. , Dudley B.D. , Graham S. , Srinivasan M.S.
Published: November 2017

Understanding seasonal partitioning of water in riparian areas is important for assessing how vegetation affects water resources. A combined hydrological‐isotopic field study was conducted within a headwater catchment to explore the dynamics of stream discharge and the effect of riparian evapotranspiration on summer low‐flow conditions. In addition to collection of meteorological data and depth to unconfined groundwater, streamflows were measured at three locations along the length of the river. Isotope ratios of local precipitation, stream water, groundwater, and willow xylem water were used to estimate pathways and sources of water used by vegetation. Using meteorological variables, leaf area index and stand area measurements, willow transpiration was estimated using the Penman–Monteith method. Combining the data from hydrometric, isotope, and vegetation evapotranspiration analysis revealed that water abstraction by stream‐side willows peaked to 5.6 mm/day and had a distinct impact on summer low‐flow conditions and patterns of stream discharge at the daily time scale. Average annual willow transpiration was 270 mm, whereas average annual precipitation during the study period was 1067 mm. However, willow transpiration reduced streamflow and altered water budgets most strongly during critical summer low‐flow periods. Our analysis of transit times, young water fraction, and depth to groundwater water data showed Waipara headwater areas have limited water storage capacity, making them vulnerable to annual variations in precipitation and any other changes in water usage. Removal of streamside willows could potentially influence water balance during summer months when flows tend to be the lowest.
From Paramagnetic to Single‐Molecule Magnet Behaviour in Heterobimetallic Compounds Containing the Tetrakis(thiocyanato‐κN)cobaltate(II) Anion
Authors: Kalinke Lucas H. G. , Cardoso Jocielle C. O. , Rabelo Renato , Valdo Ana K. , Martins Felipe T. , Cano Joan , Julve Miguel , Lloret Francesc , Cangussu Danielle
Published: November 2017

Four heterobimetallic compounds of formula [Ni(Me6trans[14]dieneN4)][Co(NCS)4] (1 and 2), [Ni(Me6trans[14]dieneN4)]2[Co(NCS)4](ClO4)2·H2O (3) and [Ni(Me6trans[14]dieneN4)]2[Co(NCS)4](PF6)2 (4) (Me6trans[14]dieneN4 = 5,7,7,12,14,14‐hexamethyl‐1,4,8,11‐tetraazacyclotetradeca‐4,11‐diene) have been synthesised and structurally characterised. Their structures are formed of square‐planar [Ni(Me6trans[14]dieneN4)]2+ cations and tetrahedral [Co(NCS)4]2– anions. The variable‐temperature magnetic properties of 2–4 mainly obey the zero‐field splitting effects (D) of the 4A2 ground‐state term of the pseudo‐tetrahedral [Co(NCS)4]2– anionic complex (2D is the energy gap between the |±1/2> and |±3/2> levels of the spin quadruplet when E = 0), the square‐planar nickel(II) unit being diamagnetic. Analysis of their magnetic data through the spin Hamiltonian H = D[Sz2 – S(S + 1)/3] + E(Sx2 – Sy2) + gβHS led to the following best‐fit parameters: g = 2.216(17), D = +3.74(12) cm–1 and E/D = 0.0137(6) for 2, g = 2.335(20), D = +11.6(4) cm–1 and E/D = 0.002(4) for 3 and g = 2.298(15), D = +7.29(17) cm–1 and E/D = 0.068(3) for 4. The Q‐band EPR spectra of powdered samples of 2–4 in the temperature range 4.0–20 K support the positive signs of D. With an applied dc field, the ac susceptibility data for 3 and 4 below 4.5 K reveal a slow magnetic relaxation, which is a characteristic of single‐ion magnet (SIM) behaviour.
Revealing the Unique Properties of Platinum(II) Complexes with Bidentate Bis(o‐carborane) Ligands
Authors: Li Wenqian , Yan Xi , Zhang Huize , He Rongxing , Li Ming , Shen Wei
Published: November 2017

The phosphorescent transition‐metal complexes (PTMCs) of the bidentate 1,1′‐bis(o‐carborane) (bc) ligand were theoretically studied for the first time. Density functional theory (DFT) and time‐dependent density functional theory (TD‐DFT) were utilized to elucidate the relationship between the structures and properties of complexes with different binding modes and increasing numbers of carboranes. Compared with previous common bidentate ligands, the introduction of bulky carboranes enormously changes the electronic structures, electroluminescence properties (including phosphorescence emission band, radiative and non‐radiative decay processes), and intermolecular interactions of the complexes. The various binding modes between the bc ligand and the metal center only influence the degree of structural distortion and the intermolecular interactions. Based on our analysis, a series of complexes were designed by introducing different substituents at the B(12) position to tune the phosphorescence properties of these complexes, which reveals a potentially new avenue for the design of novel PTMCs to be used in organic light‐emitting diodes (OLEDs).
From Organic Azides through Titanium Triazenido Complexes to Titanium Imides
Authors: Manßen Manfred , Weimer Irina , Adler Christian , Fischer Malte , Schmidtmann Marc , Beckhaus Rüdiger
Published: November 2017

The reactions of organic azides (RN3; R = 2,6‐dimesitylphenyl, SiMe3) with bis(η5:η1‐pentafulvene)titanium complexes 1 and titanium monopentafulvene complexes [Cp#Ti(η5:η1‐pentafulvene)Cl] (5; #: R5 = H, Me) were investigated. For complexes 1, insertion of the γ‐N atom of the azide into the Ti–Cexo bond results in the formation of titanium triazenido complexes 2 in good yields. Complexes 2 undergo subsequent rearrangements in solution to titanium imido complexes 3 and 4 through release of N2. Due to a haptotropic shift of the fulvene ligands, C–C coupling of the fulvenes occurs and leads to a new chelating cyclopentadienyl allyl system. By the use of the Lewis donor 4‐chlorobenzonitrile these imido complexes are stabilized. Monopentafulvene complexes 5 directly generate chlorido‐bridged titanium imido complexes 6 by release of N2 and the fulvene ligand. These new compounds were characterized by NMR spectroscopy and single‐crystal XRD.
Mechanisms and Origins of Chemoselectivities of Gold(I)‐Catalyzed Nitrogenations of Alkynes with Trimethylsilyl Azide: A Computational Study
Authors: Wen Xiuling , Deng Jiaojiao , Sheng Qiang , Li Juan
Published: November 2017

Recently, Jiao and co‐workers reported an unprecedented gold‐catalyzed nitrogenation of alkynes with trimethylsilyl azide through C–C and C≡C bond cleavages. In this reaction, the acidic additive controls the chemoselectivity for the formation of either carbamides or aminotetrazoles from an internal alkyne. In this study, density functional theory calculations were performed to clarify the mechanism and origin of this chemoselectivity. A systematic search shows that the acidities of CH3SO3H and CF3SO3H determine which of the two reaction pathways is followed and, thus, the chemoselectivity. CH3SO3H favors the hydroxylation step and eventually leads to carbamide production. In contrast, CF3SO3H, which is a stronger acid than CH3SO3H, favors trimethylsilyl removal and eventually generates aminotetrazoles. This acid‐dependent chemoselectivity also applies to terminal alkynes and is consistent with the corresponding experimental results. Both CH3SO3H and CF3SO3H form carbamides preferentially because the hydrogen atom in a terminal alkyne promotes nucleophilic hydration more effectively than the n‐butyl group in an internal alkyne.
Organylselanyl α‐Amino Phosphonates: Synthesis, NMR Spectroscopic Study, and Antioxidant and Antinociceptive Activities
Authors: Gabriela Vogt Ane , Perin Gelson , Luchese Cristiane , da Silva Patrícia Cecília , Antunes Wilhelm Ethel , Santos Silva Márcio
Published: November 2017

A simple and environmentally benign protocol for the Kabachnik–Fields reaction of aldehydes, selanylamines, and diorganylphosphites catalysed by niobic acid (Nb2O5·nH2O) has been described, leading to the formation of selanyl α‐amino phosphonates under solvent‐free reaction conditions. 77Se {1H} and 31P{1H} NMR spectroscopy was used for quantification of diastereomeric ratios, mechanistic investigation, and evaluation of the stability of the products. In addition, in‐vitro experiments were carried out to investigate the antioxidant and anticholinesterase activities of the selanyl α‐amino phosphonates. In‐vivo and ex‐vivo experiments were carried out to investigate the potential antinociceptive effect, as well as the acute toxicity. We found that this class of compounds has the potential to act against oxidative stress and to be used for the treatment of painful clinical conditions.
Straight to heaven: Rectitude as spatial representation of morality
Authors: Pacilli Maria Giuseppina , Pagliaro Stefano , Spaccatini Federica , Giovannelli Ilaria , Sacchi Simona , Brambilla Marco
Published: November 2017

Abundant literature in cognitive sciences has shown that morality is grounded in bodily experience. Four studies tested the perceptual association between the spatial dimension of straightness and the abstract concept of morality. Study 1 (n = 61) employed an IAT and revealed an association between straight figures and moral related words. Study 2 (n = 83) employed a similar paradigm and further revealed that the effect we found in Study 1 cannot be attributable to the general association between straight figures and positivity. Study 3 (n = 64) revealed that participants showed a stronger preference for straight figures after recalling moral (vs. immoral) deeds. Study 4 (n = 183) showed the specific role of morality, in this sense, as recalling sociable (vs. unsociable) deeds had no significant influence on figure preferences. A small‐scale meta‐analysis confirmed the robustness of our findings. Results are discussed in light of the embodiment theory.
Solenoid Micro‐pumps: A New Tool for Sample Introduction in Batch Injection Analysis Systems with Electrochemical Detection
Authors: Rocha Diego P. , Cardoso Rafael M. , Mendonça Dianderson M. H. , Richter Eduardo M. , da Silva Sidnei G. , Batista Alex D. , Muñoz Rodrigo A. A.
Published: November 2017

This work presents the use of solenoid micro‐pumps as a new strategy for sample introduction in batch‐injection analysis (BIA). The volume of solution dispensed on each pulse of the solenoid micro‐pump (μL) is used as fixed and reproducible injection volume for BIA. In this system, the injection steps are possible in stopped flow mode resulting in low background noise levels, which would not be possible under continuous flow conditions and using solenoid micro‐pumps. As a proof‐of‐concept, amperometric and square‐wave voltammetric (SWV) determination of dopamine was demonstrated as well as anodic‐stripping voltammetry (ASV) of metals. The micro‐pump provided injections of 14 μL of solution per pulse at 512 μL s−1 over the electrode during electrochemical measurement. Moreover, fast injections of analyte or electrolyte were programmed during deposition or conditioning steps of ASV for analyte preconcentration or electrode cleaning. The proposed system improved limits of detection and sensitivity (2‐fold), precision and sample throughput in comparison with traditional BIA due to enhanced mass transfer and consequent reduced dispersion of analyte, and possible control of injections without analyst intervention. This work opens new possibilities of applications of the BIA system, including on‐line sample treatment (derivatization or dilution steps).
Dielectrophoretic choking phenomenon of a deformable particle in a converging‐diverging microchannel
Authors: Zhou Teng , Ge Jian , Shi Liuyong , Fan Junqing , Liu Zhenyu , Woo Joo Sang
Published: November 2017

The translational motion of small particles in an electrokinetic fluid flow through a constriction can be enhanced by an increase of the applied electric potential. Beyond a critical potential, however, the negative dielectrophoresis (DEP) can overpower other forces to prevent particles that are even smaller than the constriction from passing through the constriction. This DEP choking phenomenon was studied previously for rigid particles. Here, the DEP choking phenomenon is revisited for deformable particles, which are ubiquitous in many biomedical applications. Particle deformability is measured by the particle shear modulus, and the choking conditions are reported through a parametric study that includes the channel geometry, external electric potential, and particle zeta potential. The study was carried out using a numerical model based on an arbitrary Lagrangian‐Eulerican (ALE) finite‐element method.
Smartphone‐based colorimetric chiral recognition of ibuprofen using aptamers‐capped gold nanoparticles
Authors: Ping Jing , He Zhenjiang , Liu Jianshe , Xie Xuehui
Published: November 2017

Sensitive and fast detection of ibuprofen enantiomers is very critical for required routine monitoring and risk assessment of trace pollutants in water samples. Here a simple, rapid and highly sensitive android smartphone application for chiral recognition was developed. Aptamer‐capped gold nanoparticles (AuNPs) was demonstrated as an efficient detection platform for (S)‐(+)‐ibuprofen (S‐Ibu) and (R)‐(‐)‐ibuprofen (R‐Ibu). Detachment of an enantioselective aptamer from the AuNPs surface and binding with an enantiomer of Ibu lead to AuNPs aggregation, which allows a rapid enantiodiscrimination of Ibu by monitoring the absorbance changes of AuNPs solution in the UV‐vis spectrum. Under optimal conditions, the limit of detection for S‐Ibu and R‐Ibu was 1.24 and 3.91 pg/mL, respectively. These probes showed good chiral recognition ability in mixed samples (i.e. S‐Ibu + R‐Ibu) and environmental samples. These advantages can be further developed by quantitative measurement with smartphone, which opens new opportunities for on‐site detection of trace chiral pollutants in a simple and practical manner.
Into the theory of the partial‐filling affinity capillary electrophoresis and the determination of apparent stability constants of analyte‐ligand complexes
Authors: Ansorge Martin , Dubský Pavel , Ušelová Kateřina
Published: November 2017

The partial‐filling affinity capillary electrophoresis (pf‐ACE) works with a ligand present in a background electrolyte that forms a weak complex with an analyte. In contrast to a more popular mobility‐shift affinity capillary electrophoresis, only a short plug of the ligand is introduced into a capillary in the pf‐ACE. Both methods can serve for determining apparent stability constants of the formed complexes but this task is hindered in the pf‐ACE by the fact that the analyte spends only a part of its migration time in a contact with the ligand. In 1998, Amini and Westerlund published a linearization strategy that allows for extracting an effective mobility of an analyte in the presence of a neutral ligand out of the pf‐ACE data. The main purpose of this paper is to show that the original formula is only approximate. We derive a new formula and demonstrate its applicability by means of computer simulations. We further inspect several strategies of data processing in the pf‐ACE regarding a risk of an error propagation. This establishes a good practice of determining apparent stability constants of analyte‐ligand complexes by means of the pf‐ACE.
Modern Ni and Pd–Ni Catalysts Supported on Sn–Al Binary Oxide for Oxy‐Steam Reforming of Methanol
Authors: Mierczynski Pawel , Mierczynska Agnieszka , Ciesielski Radoslaw , Maniukiewicz Waldemar , Rogowski Jacek , Maniecki Tomasz P. , Dubkov Sergey , Sysa Artem , Gromov Dmitry , Szynkowska Malgorzata I. , Vasilev Krasimir
Published: November 2017

Monometallic Ni and bimetallic Pd–Ni catalysts supported on mono‐SnO2 and SnO2–Al2O3 binary oxide are prepared using a wet impregnation and subsequent impregnation method. The catalysts are tested in oxy‐steam reforming of methanol (OSRM) and characterized. The activity measurements show that palladium‐promoted nickel catalysts supported on SnO2–Al2O3 exhibit high activity, selectivity towards hydrogen formation, and stability. The effect of Pd on reducibility, surface acidity, and morphology of the Ni supported catalyst, as well as its catalytic properties in OSRM, are discussed in detail.
Energetic and exergetic carbon dioxide equivalents and prices of the energy sources for buildings in Turkey
Authors: Yildiz Ibrahim , Caliskan Hakan
Published: November 2017

In this study, the energy and exergy prices of the coal, diesel oil, electricity, fuel oil, LPG, natural gas, air source heat pump (ASHP) and ground source heat pump (GSHP) along with their energetic and exergetic carbon dioxide (CO2) equivalents are evaluated basing on 12‐month data of 2016 (from January to December) for residential and industrial sectors in Turkey. Also, they are considered as district heating energy sources/fuels to heat the 100 m2 floor area in the residential and industrial applications. For the residential and industrial sectors, the minimum energy & exergy prices and energetic & exergetic CO2 equivalents are found for the GSHP; while the corresponding maximum energy and exergy rates are obtained for the LPG. Also, the quantity of fuel required for the desired period is calculated for each one of the energy sources. If the residential and industrial sectors are considered together, the minimum amount of required fuel is found for the LPG as 16.3 kg/°Ch; while the maximum one is found for the coal (for residential sector) to be 44.25 kg/°Ch. © 2017 American Institute of Chemical Engineers Environ Prog, 37: 912–925, 2018
Depth‐integrated nonhydrostatic free‐surface flow modeling using weighted‐averaged equations
Authors: Cantero‐Chinchilla F.N. , Castro‐Orgaz O. , Khan A.A.
Published: November 2017

In this study, a depth‐integrated nonhydrostatic flow model is developed using the method of weighted residuals. Using a unit weighting function, depth‐integrated Reynolds‐averaged Navier‐Stokes equations are obtained. Prescribing polynomial variations for the field variables in the vertical direction, a set of perturbation parameters remains undetermined. The model is closed generating a set of weighted‐averaged equations using a suitable weighting function. The resulting depth‐integrated nonhydrostatic model is solved with a semi‐implicit finite‐volume finite‐difference scheme. The explicit part of the model is a Godunov‐type finite‐volume scheme that uses the Harten‐Lax‐van Leer‐contact wave approximate Riemann solver to determine the nonhydrostatic depth‐averaged velocity field. The implicit part of the model is solved using a Newton‐Raphson algorithm to incorporate the effects of the pressure field in the solution. The model is applied with good results to a set of problems of coastal and river engineering, including steady flow over fixed bedforms, solitary wave propagation, solitary wave run‐up, linear frequency dispersion, propagation of sinusoidal waves over a submerged bar, and dam‐break flood waves.
Price discovery in dual‐class shares across multiple markets
Authors: Fernandes Marcelo , Scherrer Cristina M.
Published: November 2017

This paper proposes a new measure of price discovery that uses the spectral decomposition. The methodology is especially important in the context of large price systems, such as interest rate parities with spot and futures contracts or dual‐class shares in multiple markets. We employ high frequency data to study price discovery in dual‐class Brazilian stocks and their ADRs. We find that the foreign market is at least as informative as the home market and that shocks in the dual‐class premium entail a permanent effect in normal times, but transitory in periods of financial distress
Return predictability and contrarian profits of international index futures
Authors: Tse Yiuman
Published: November 2017

Using futures markets, we examine the lead‐lag relationships among 11 industrialized countries. Lagged monthly returns for several countries have return predictability comparable to those in the United States for the 1988–2016 period. The international futures markets are more correlated in market downturns, while the lead‐lag relationships are more significant in market upturns. Consistent with these asymmetric relationships, a contrarian strategy (in particular, by buying the losers) offers significant profits in an up market but not in a down market. The contrarian profits are not captured by a factor model using global equity factors and momentum profits.