bluuebunny/crossref_metadata_2025_split huggingface dataset:
Operando Modeling of Multicomponent Reactive Solutions in Homogeneous Catalysis: from Non‐standard Free Energies to Reaction Network Control
Authors: Kuliaev Pavel O. , Pidko Evgeny A. 
Published: October 2019

AbstractOptimization and execution of chemical reactions are to a large extend based on experience and chemical intuition of a chemist. The chemical intuition is rooted in the phenomenological Le Chatelier's principle that teaches us how to shift equilibrium by manipulating the reaction conditions. To access the underlying thermodynamic parameters and their condition‐dependencies from the first principles is a challenge. Here, we present a theoretical approach to model non‐standard free energies for a complex catalytic CO2 hydrogenation system under operando conditions and identify the condition spaces where catalyst deactivation can potentially be suppressed. Investigation of the non‐standard reaction free energy dependencies allows rationalizing the experimentally observed activity patterns and provides a practical approach to optimization of the reaction paths in complex multicomponent reactive catalytic systems.
Exploring the Relationship between BODIPY Structure and Spectroscopic Properties to Design Fluorophores for Bioimaging
Authors: Donnelly Joanna L. , Offenbartl‐Stiegert Daniel , Marín‐Beloqui José M. , Rizzello Loris , Battaglia Guiseppe , Clarke Tracey M. , Howorka Stefan , Wilden Jonathan D. 
Published: October 2019

AbstractDesigning chromophores for biological applications requires a fundamental understanding of how the chemical structure of a chromophore influences its photophysical properties. We here describe the synthesis of a library of BODIPY dyes, exploring diversity at various positions around the BODIPY core. The results show that the nature and position of substituents have a dramatic effect on the spectroscopic properties. Substituting in a heavy atom or adjusting the size and orientation of a conjugated system provides a means of altering the spectroscopic profiles with high precision. The insight from the structure–activity relationship was applied to devise a new BODIPY dye with rationally designed photochemical properties including absorption towards the near‐infrared region. The dye also exhibited switch‐on fluorescence to enable visualisation of cells with high signal‐to‐noise ratio without washing‐out of unbound dye. The BODIPY‐based probe is non‐cytotoxic and compatible with staining procedures including cell fixation and immunofluorescence microscopy.
Formation of Active Cyclic Five‐membered Frustrated Phosphane/Borane Lewis Pairs and their Cycloaddition Reactions
Authors: Dong Shunxi , Daniliuc Constantin G. , Kehr Gerald , Erker Gerhard 
Published: October 2019

AbstractThe cyclic five‐membered frustrated phosphane/borane Lewis pairs11 a,bfeaturing the bulky octaethylhydrindacenyl‐ (Eind) substituent or its mono‐bromo derivative (BrEind) at phosphorus are monomeric at room temperature. The reactive frustrated Lewis pairs (FLPs) cleave dihydrogen. The cyclic FLP11 b(BrEind) undergoes 1,2‐P/B addition to ethylene to give the zwitterionic heteronorbornane derivative 14 b. It reacts similarly with the carbon–carbon double bond of norbornene. With a variety of organic π‐reagents, the cyclic FLP11 boften undergoes reaction sequences reminiscent of the Alder–Rickert reaction: the cycloaddition reaction is followed by rapid cycloreversion to form new five‐membered heterocyclic FLP products with extrusion of ethene. Reactions of11 bwith benzaldehyde or with acetylenes follow this reaction pattern.
Enantioselective degradation of dufulin pesticide in water: Uptake, thermodynamics, and kinetics studies
Authors: Al‐Shaalan Nora Hamad , Ali Imran , ALOthman Zeid A. , Al‐Wahaibi Lamya Hamad , Alabdulmonem Hadeel 
Published: October 2019

AbstractKudzu (Pueraria thunbergiana) plant extract impregnated sediments were used for abiotic and biotic uptakes and biodegradation. The optimized conditions were 25 μg L−1 concentration, 7 days for abiotic uptake and 56 days for biotic uptake and biodegradation, dose 2 g L−1, 7 pH, and 35°C temperature. The amount removed of dufulin was 32.6% in abiotic conditions while these were 90% in the case of biotic uptake and biodegradation. Enantioselective biodegradation indicated that S‐(+)‐enantiomer degraded faster (90%) than R‐(−)‐enantiomer (87%). The data for abiotic and biotic uptakes and biodegradation followed well Langmuir, thermodynamics, and kinetics models. All these processes followed pseudo first‐order kinetics. It was observed that biodegradation was three times responsible for dufulin removal than simple sorption uptake (abiotic and biotic). The abiotic and biotic uptakes and biodegradation were quite fast and endothermic nature. The developed method may be used to remove the racemic and enantiomeric dufulin in water.
Enhanced Catalytic Oxidation of CO on Sulfur‐Doped Boron Nitride
Authors: Liu Bingping , Lee Jin Yong , Yan Shihai 
Published: October 2019

AbstractBridging the gap between homogeneous and heterogeneous catalysis, the single‐atom catalyst supported on a substrate shows extremely high atom efficiency, low cost, excellent stability, and high activity for CO oxidation. Here, we report the catalytic mechanism of CO oxidation on sulfur‐doped h‐BN. The chemisorption activates O2 via electron transfer from sulfur‐doped h‐BN, inducing a reduction in the bond order of O2 and lengthening the O−O distance. This variation is helpful for the subsequent oxidation of CO. The oxidation process includes O2 adsorption, electron reorganization, and two instances each of CO adsorption, oxygen transfer, and CO2 desorption. The first oxygen transfer from O2 to CO occurs exothermically by ∼−63.8 kcal/mol with a barrier of ∼12.1 kcal/mol, which is thus the rate‐determining step. The significantly enhanced catalytic performance implies that sulfur doping on h‐BN should have potential applications in the areas of metal‐free catalysts with low cost and high activity.
Laser‐Assisted Fabrication of Pseudohexagonal Phase Niobium Pentoxide Nanopillars for Lithium Ion Battery Anodes
Authors: Liang Dewei , Hu Lei , Wang Lili , Liu Lingli , Liang Sheng , Yang Lei , Zhou Ningning , Liang Changhao 
Published: October 2019

AbstractHerein, we report a convenient route to fabricate pseudohexagonal phase niobium pentoxide (TT‐Nb2O5) nanopillars via combination of laser ablation in liquids (LAL) and hydrothermal treatment without using any organic surfactants or stabilizers. The morphology and structure of the as‐synthesized samples are investigated through scanning and transmission electron microscopy, X‐ray diffraction, and X‐ray photoelectron spectroscopy. Such nanopillars exhibit excellent lithium storage properties, including high reversible capacity, good rate capability, and excellent cycle stability (81% capacity retention after 1000 cycles) at a rate of 5 C in the potential range of 1.0 to 3.0 V, which is higher than other previously reported Nb2O5‐based electrode. The synergistic effects from the nanopillar morphology, high electronic conductivity and stable structure promise potential applications in high‐security and high‐rate capability Li‐ion batteries.
Synthesis and Binding Properties of a Tren‐Capped Hexahomotrioxacalix[3]arene
Authors: Zahim Sara , Ajami Daniela , Laurent Pascal , Valkenier Hennie , Reinaud Olivia , Luhmer Michel , Jabin Ivan 
Published: October 2019

AbstractThe straightforward synthesis of a new hexahomotrioxacalix[3]arene‐based ligand capped by a tren subunit was developed and the binding properties of the corresponding zinc complex were explored by NMR spectroscopy. Similarly to the closely related calix[6]tren‐based systems, the homooxacalixarene core ensures the mononuclearity of the zinc complex and the metal center displays a labile coordination site for exogenous guests. However, very different host–guest properties were observed: i) in CDCl3, the zinc complex strongly binds a water molecule and is reluctant to recognize other neutral guests, ii) in CD3CN, the exo‐coordination of anions prevails. Thus, in strong contrast to the calix[6]tren‐based systems, the coordination of neutral guests that thread through the small rim and fill the polyaromatic cavity was not observed. This unique behaviour is likely due to the fact that the 18‐membered ethereal macrocycle is too small to let a molecule threading through it. This work illustrates the key role played by the second coordination sphere in the binding properties of metal complexes.
Design of a compact T‐shaped slot antenna for wireless applications
Authors: Thiripurasundari C. , Mahadevi M. , Sumathy V. , Thiruvengadam C. 
Published: October 2019

SUMMARYIn this paper, the design of a penta‐band slot radiator for the WLAN (2.26‐2.61 GHz), WiMAX (3.14‐4.49 GHz), and C band (4‐8 GHz) antenna design and fabrication process is proposed. The proposed system (antenna) has a dielectric substrate material and radiating patch (T‐shaped) with an inverted‐L slot (both left and right sides of the feed), circle slot, and comb‐shaped ground structure on the back of the substrate. The proposed dimension of the antenna is 20 × 30 mm2, and it is designed and fabricated on FR4 substrate. It can be designed to cover the frequency bands of 2.61, 3.12, 4.32, 6.54, and 7.62 GHz. It can be designed using advanced design system (ADS) and measured using vector network analyzer (VNA). The obtained simulation result of the proposed antenna is achieved with better return loss.
Throughput enhanced scheduling (TES) scheme for ultra‐dense networks
Authors: Haci Huseyin , Abdelbari Amr 
Published: October 2019

SummaryThis paper proposes two novel packet scheduling schemes, called as throughput enhanced scheduling (TES) and TES plus (TES+), for future ultra‐dense networks. These schemes introduce two novel parameters to the scheduling decision making and reformulate the parameters used by the state‐of‐the‐art schemes. The aim is to have a more balanced weight distribution between delay and throughput‐related parameters at scheduling decisions. Also include a new telecommunications related parameter into scheduling decision making that has not been studied by popular schedulers. The performance of novel schemes is compared with well‐known schemes—proportional fairness (PF), exponential/proportional fairness (EXP/PF), and M‐LWDF. For performance evaluation, five performance metrics—average spectral efficiency and delay, quality of service (QoS) violation ratio, jitter, and Jain's fairness index—are investigated. The simulation results show that proposed schemes can outperform all the compared scheduling schemes.
Constraining past environmental changes of cold‐water coral mounds with geochemical proxies in corals and foraminifera
Authors: Raddatz Jacek , Rüggeberg Andres 
Published: October 2019

AbstractCold‐water coral (CWC) reefs and mounds are and have been biodiversity hotspots of the deep sea. As their occurrence depends on specific environmental parameters, gaining hindsight on changing ocean conditions under on‐going climate change is the key to a better understanding of CWC mound development through time. A convenient technique for reconstructing the palaeoenvironment during periods of CWC mound growth is by extracting geochemical proxies from biologically mediated carbonates. Here, the focus is on probably the two most abundant calcareous archives, that are, cold‐water Scleractinia and Foraminifera, with an overview of the geochemical proxies (selection) used in these aragonitic and calcitic skeletons from CWC mounds. A particular emphasis is set on constraining proxies for temperature, salinity, seawater density, seawater carbonate systems parameters (pH, CO32−), nutrients, oxygen and water mass tracers.
Comparison and optimization of SAR‐PAGE tests for erythropoietins in doping analysis
Authors: Zhou Xinmiao , Zhang Lisi , He Sen , Shen Li , He Chunji 
Published: October 2019

AbstractErythropoietins (EPOs) are substances listed in S2 of the World Anti‐Doping Agency (WADA) Prohibited List and are used commonly by athletes to increase endurance performance. According to the current WADA Technical Documents, sarcosyl‐polyacrylamide gel electrophoresis (SAR‐PAGE) followed by western blotting to differentiate erythropoietins based on their molecular weights is the only method that can be used for both screening and confirmation of all types of erythropoietins. The efficiency of immunopurification and protein transfer is crucial for ensuring the selectivity and sensitivity of erythropoietin detection. Several comparisons and optimization of the SAR‐PAGE tests were conducted in this study. We optimized the first blotting conditions and then compared different immunopurification methods based on their selectivity, repeatability, and sensitivity for both urine and blood analysis. Additionally, rapid procedures for both urine and blood analysis were established and compared. The two‐step procedure at 1.0 mA/cm2 for 60 min followed by 1.56 mA/cm2 for 20 min increased the blotting efficiency compared with the commonly used constant current approach. Comparison of immunopurification revealed no significant difference in selectivity and sensitivity between the different methods. For other factors, such as operation complexity, time and cost, a StemCell® purification kit followed by single blotting and magnetic beads followed by double blotting are recommended for urine screening and confirmation, respectively. While magnetic beads and a MAIIA® kit followed by double blotting are recommended for both screening and confirmation of blood samples, respectively. To ensure high sensitivity and selectivity, double blotting is recommended for a rapid procedure for both urine and blood analysis.
Small mammal responses to long‐term large‐scale woodland creation: the influence of local and landscape‐level attributes
Authors: Fuentes‐Montemayor Elisa , Ferryman Mark , Watts Kevin , Macgregor Nicholas A. , Hambly Natasha , Brennan Stephen , Coxon Ruth , Langridge Holly , Park Kirsty J. 
Published: October 2019

AbstractHabitat loss and fragmentation greatly affect biological diversity. Actions to counteract their negative effects include increasing the quality, amount and connectivity of seminatural habitats at the landscape scale. However, much of the scientific evidence underpinning landscape restoration comes from studies of habitat loss and fragmentation, and it is unclear whether the ecological principles derived from habitat removal investigations are applicable to habitat creation. In addition, the relative importance of local‐ (e.g., improving habitat quality) vs. landscape‐level (e.g., increasing habitat connectivity) actions to restore species is largely unknown, partly because studying species responses over sufficiently large spatial and temporal scales is challenging. We studied small mammal responses to large‐scale woodland creation spanning 150 yr, and assessed the influence of local‐ and landscape‐level characteristics on three small mammal species of varying woodland affinity. Woodland specialists, generalists, and grassland specialists were present in woodlands across a range of ages from 10 to 160 yr, demonstrating that these species can quickly colonize newly created woodlands. However, we found evidence that woodlands become gradually better over time for some species. The responses of individual species corresponded to their habitat specificity. A grassland specialist (Microtus agrestis) was influenced only by landscape attributes; a woodland generalist (Apodemus sylvaticus) and specialist (Myodes glareolus) were primarily influenced by local habitat attributes, and partially by landscape characteristics. At the local scale, high structural heterogeneity, large amounts of deadwood, and a relatively open understory positively influenced woodland species (both generalists and specialists); livestock grazing had strong negative effects on woodland species abundance. Actions to enhance habitat quality at the patch scale focusing on these attributes would benefit these species. Woodland creation in agricultural landscapes is also likely to benefit larger mammals and birds of prey feeding on small mammals and increase ecosystem processes such as seed dispersal.
Scale‐dependent intraspecific competition of Taurus cedar (Cedrus libani A. Rich.) saplings in the Southern Turkey
Authors: Yılmaz Osman Yalçın , Kavgacı Ali , Sevgi Orhan , Örtel Erdal , Tecimen Hüseyin Barış , Çobanoğlu Abdurrahman , Yeşil İsmet 
Published: October 2019

AbstractBetter understanding of the competitive interaction at the early development stages of the stand is crucial to help schedule silvicultural treatments for young stands and for the better management of the future stands. We used scale‐dependent analysis to improve our understanding of sapling dynamics in the pure Taurus cedar (Cedrus libani A. Rich.) stands in Southern Turkey. Using data from nine plots established at the western Taurus Mountains, diameter, height, and crown radii of saplings were compared, and spatial point pattern analyses were performed. We found significant differences for the mean diameter and height, and crown radii of saplings among the plots. Univariate pair correlation function showed that sapling pattern was regular only at small scales (r < 0.4 m) but was predominantly random. Bivariate pair correlation function revealed no evidence of spatial interaction between tall saplings and short saplings. Univariate mark correlation function revealed that strong intraspecific competition was detected at small scales (up to 0.55 m). This distance is reasonable for the juvenile age tending of Taurus cedar saplings and should be under consideration during silvicultural treatments to use the site productivity more efficiently.
Resilience to changes in lake trophic state: Nutrient allocation into Daphnia resting eggs
Authors: Isanta Navarro Jana , Kowarik Carmen , Wessels Martin , Straile Dietmar , Martin‐Creuzburg Dominik 
Published: October 2019

AbstractDuring past decades, many lakes underwent drastic human‐caused changes in trophic state with strong implications for population dynamics and food web processes. We investigated the influence of trophic state on nutrient allocation into Daphnia resting eggs. The production of resting eggs is an important survival strategy, allowing Daphnia to cope with unfavorable environmental conditions. Allocation of essential nutrients into resting eggs may crucially influence embryonic development and offspring survival and thus is of great ecological and evolutionary interest. The capacity of Daphnia to adjust the allocation of nutrients into resting eggs may depend on the dietary nutrient supply, which may vary with trophic state‐related changes in the phytoplankton community composition. Resting eggs were isolated from sediment cores taken from Lake Constance, a large prealpine lake with a distinct eutrophication and reoligotrophication history, and analyzed for elemental (carbon, nitrogen, and phosphorus) and biochemical (sterols and fatty acids) nutrients. Carbon allocation into Daphnia resting eggs continuously decreased over time, irrespective of changes in trophic state. The allocation of nitrogen into Daphnia resting eggs followed the changes in trophic state, that is, nitrogen concentrations in resting eggs increased with eutrophication and decreased again with reoligotrophication. The allocation of phosphorus, sterols and long‐chain polyunsaturated fatty acids, such as eicosapentaenoic acid, into Daphnia resting eggs did not change significantly over time. Changes in trophic state strikingly influenced all trophic levels in Lake Constance. However, nutrient allocation into Daphnia resting eggs was mostly resilient to changes in lake trophic state.
Fibromyalgia syndrome—A laser‐evoked potentials study unsupportive of small nerve fibre involvement
Authors: Van Assche Dominique C. F. , Plaghki Leon , Masquelier Etienne , Hatem Samar M. 
Published: October 2019

AbstractBackgroundFibromyalgia syndrome (FMS) is a chronic pain syndrome characterized by widespread pain and a variety of non‐pain symptoms. Central sensitivity phenomena are found consistently in FMS. Additionally, several researchers proclaimed that a subgroup of FMS patients may present with unrecognized peripheral small fibre neuropathy (SFN). Laser‐evoked brain potentials (LEP) are considered as a reliable method for the functional assessment of the thermo‐nociceptive system, including the evaluation of SFN.ObjectivesThe aim of this retrospective study was to estimate the prevalence of thermo‐nociceptive system dysfunction based on LEPs in FMS.MethodsLEP recordings of 92 FMS patients and 39 age and gender‐matched healthy controls were selected from a database collected between 2003 and 2012 with standardized settings for laser stimulation and EEG recording. The N1, N2 and P2 LEP components were identified and characterized by peak latency and amplitude.ResultsNone of the FMS patients showed signs of loss of function of the nociceptive responses evoked by A δ‐nociceptor activation, compared to healthy controls. 6.5% of the FMS patients had N2‐P2 peak‐to‐peak amplitudes above the upper limit of the 99%‐confidence interval. N2‐P2 peak‐to‐peak amplitudes were negatively correlated with age, without age‐related differences between groups.ConclusionsThe characteristic signs of a damaged thermo‐nociceptive system as revealed by LEPs were absent in this large cohort of FMS patients.SignificanceThe present research does not support the hypothesis that small fibre neuropathy is a significant contributor to the pathophysiology of FMS.
Effect of surface conduction–induced electromigration on current monitoring method for electroosmotic flow measurement
Authors: Babar Mohammad , Dubey Kaushlendra , Bahga Supreet Singh 
Published: October 2019

AbstractCurrent monitoring method for measurement of EOF in microchannels involves measurement of time‐varying current while an electrolyte displaces another electrolyte having different conductivity due to EOF. The basic premise of the current monitoring method is that an axial gradient in conductivity of a binary electrolyte in a microchannel advects only due to EOF. In the current work, using theory and experiments, we show that this assumption is not valid for low concentration electrolytes and narrow microchannels wherein surface conduction is comparable with bulk conduction. We show that in presence of surface conduction, a gradient in conductivity of binary electrolyte not only advects with EOF but also undergoes electromigration. This electromigration phenomenon is nonlinear and is characterized by propagation of shock and rarefaction waves in ion concentrations. Consequently, in presence of surface conduction, the current–time relationships for forward and reverse displacement in the current monitoring method are asymmetric and the displacement time is also direction dependent. To quantify the effect of surface conduction, we present analytical expressions for current–time relationship in the regime when surface conduction is comparable to bulk conduction. We validate these relations with experimental data by performing a series of current monitoring experiments in a glass microfluidic chip at low electrolyte concentrations. The experimentally validated analytical expressions for current–time relationships presented in this work can be used to correctly estimate EOF using the current monitoring method when surface conduction is not negligible.