bluuebunny/crossref_metadata_2025_split huggingface dataset:
Spectroscopic Observation of a Hydrogenated CO Dimer Intermediate During CO Reduction on Cu(100) Electrodes
Authors: Pérez‐Gallent Elena , Figueiredo Marta C. , Calle‐Vallejo Federico , Koper Marc T. M. 
Published: February 2017

AbstractCarbon dioxide and carbon monoxide can be electrochemically reduced to useful products such as ethylene and ethanol on copper electrocatalysts. The process is yet to be optimized and the exact mechanism and the corresponding reaction intermediates are under debate or unknown. In particular, it has been hypothesized that the C−C bond formation proceeds via CO dimerization and further hydrogenation. Although computational support for this hypothesis exists, direct experimental evidence has been elusive. In this work, we detect a hydrogenated dimer intermediate (OCCOH) using Fourier transform infrared spectroscopy at low overpotentials in LiOH solutions. Density functional theory calculations support our assignment of the observed vibrational bands. The formation of this intermediate is structure sensitive, as it is observed only during CO reduction on Cu(100) and not on Cu(111), in agreement with previous experimental and computational observations.
Asymmetric Total Syntheses of Kopsia Indole Alkaloids
Authors: Leng Lingying , Zhou Xiaohan , Liao Qi , Wang Falu , Song Hao , Zhang Dan , Liu Xiao‐Yu , Qin Yong 
Published: February 2017

AbstractThe asymmetric total syntheses of a group of structurally complex Kopsia alkaloids, (−)‐kopsine, (−)‐isokopsine, (+)‐methyl chanofruticosinate, (−)‐fruticosine, and (−)‐kopsanone, has been achieved. The key strategies for the construction of the molecular complexity in the targets included an asymmetric Tsuji–Trost rearrangement to set the first quaternary carbon center at C20, an intramolecular cyclopropanation by diazo decomposition to install the second and third quaternary carbon centers at C2 and C7, respectively, and a SmI2‐promoted acyloin condensation to assemble the isokopsine core. A radical decarboxylation of an isokopsine‐type intermediate results in a thermodynamic partial rearrangement to give N‐decarbomethoxyisokopsine and N‐decarbomethoxykopsine, two key intermediates for the syntheses of Kopsia alkaloids with different subtype core structures.
Hydroxy‐Directed Ruthenium‐Catalyzed Alkene/Alkyne Coupling: Increased Scope, Stereochemical Implications, and Mechanistic Rationale
Authors: Rummelt Stephan M. , Cheng Gui‐Juan , Gupta Puneet , Thiel Walter , Fürstner Alois 
Published: February 2017

AbstractThe recognition of the dual binding mode of propargyl and allyl alcohols to [Cp*Ru] fragments fostered the development of a highly regioselective intermolecular Alder‐ene‐type reaction of alkynes with 1,2‐disubstituted alkenes. The increased substrate scope opens new perspectives in stereochemical terms. As the loaded catalyst is chiral‐at‐metal, stereochemical information is efficiently relayed from the propargylic site to the emerging C−C bond. This interpretation is based on the X‐ray structure of the first Cp*Ru complex carrying an intact enyne ligand, and provides valuable insights into bonding and activation of the substrates. Computational data draw a clear picture of the principles governing regio‐ and stereocontrol.
Enhanced wide‐range monotonic piezoresistivity, reliability of Ketjenblack/deproteinized natural rubber nanocomposite, and its biomedical application
Authors: Madhanagopal Jagannathan , Singh Om Prakash , Sornambikai Sundaram , Omar Abdul Hafidz , Sathasivam Kathiresan V. , Fatihhi S. J. , Abdul Kadir Mohammed Rafiq 
Published: February 2017

ABSTRACTPiezoresistive behavior of 6 to 9 wt % Ketjenblack‐reinforced deproteinized natural rubber (KB/DPNR) nanocomposite developed by two‐roll mill was studied under compressive pressure (0 to 12.54 MPa). The 6 wt % KB/DPNR exhibited monotonic piezoresistivity, the highest electrical resistance change (485%), remarkable reversibility and minimal hysteresis. Furthermore, a good sensitivity (S) = 1.1 MPa−1 for 0.25 to 2.49 MPa, high test–retest reliability (intraclass correlation co‐efficient, ICC = 0.99) under 0 to 2.49 MPa for three repetitions conducted at an interval of 24 h and excellent repeatability (standard deviation, SD = 4.8%) to a swing of 6.25 MPa for 50 cyclic compression were achieved. Homogeneous dispersion and high aspect ratio of KB and higher chemical linkage (due to double crosslinking agents) between KB and DPNR may be responsible for the enhanced piezoresistivity. For practical application, the KB/DPNR was interfaced with the microcontroller through a bridge rectifier via custom‐built Simulink and successfully monitored finger pressure in real time during bone movement on human. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017, 134, 44981.
Techno‐economic assessment of biogas to liquid fuels conversion technology via Fischer‐Tropsch synthesis
Authors: Okeke Ikenna J. , Mani Sudhagar 
Published: February 2017

AbstractBiogas derived from anaerobic digestion of organic wastes, and lignocellulosic biomass can be used to produce drop‐in diesel fuel via Fischer‐Tropsch (FT) synthesis. In this study, we developed a process‐based simulation model for the biogas to liquid fuel (BgTL) plant to conduct mass and energy balances and to evaluate techno‐economic assessment of producing drop‐in FT fuels. The BgTL plant operations consisted of biogas cleaning, biomethane reforming, FT synthesis of syngas and hydrocracking and final distillation to produce drop‐in liquid fuels. The unconverted syngas and syncrude were utilized to generate steam and electricity to meet internal plant demand, while the excess power was sold to the grid. The base case BgTL plant (2 000 Nm3/h) produced about 4.6 million gallons per annum of total FT fuels which consisted of 62% diesel, 32% gasoline, 6% LPG with an overall biogas conversion of 54%. A discounted cash flow rate of return (DCFOROR) approach for the Nth plant was used to estimate the capital and operating costs with the minimum selling price for the FT drop‐in fuels of about $5.67/gal ($5.29/GGE). The increase in plant feed capacity to 20 000 Nm3/h decreased the minimum selling price to $2.06/gal ($1.92/GGE). The sensitivity analysis conducted on the base case plant demonstrated that the internal rate of return (IRR), FT conversion rate, plant operating hours, and biogas cost were the most sensitivity parameters to the minimum selling price. Overall, the BgTL technology is deemed to be economically feasible to meet US biofuels demand. © 2017 Society of Chemical Industry and John Wiley & Sons, Ltd
Hippocampal AMPARs involve the central sensitization of rats with irritable bowel syndrome
Authors: Chen Aiqin , Chen Yu , Tang Ying , Bao Chengjia , Cui Zizhi , Xiao Meng , Lin Chun 
Published: February 2017

AbstractObjectiveThe roles of hippocampal AMPARs were investigated in irritable bowel syndrome (IBS)‐like rats to clarify the central sensitization mechanisms.MethodsIBS model was induced by neonatal maternal separation. The effects of AMPARs on visceral hypersensitivity were examined by the responses of abdominal muscle to colorectal distension after the bilateral intrahippocampal injections of CNQX (an AMPAR inhibitor). The expressions of hippocampal AMPARs (GluR1 and GluR2) were determined by Western blot.ResultsThe IBS‐like rats showed visceral hypersensitivity when compared with controls. Bilateral intrahippocampal injections of CNQX alleviated the visceral pain in IBS‐like rats. The maximal effect appeared at the time point of 30 min, and the duration lasted for 90 min after CNQX application, under 40 and 60 mmHg CRD. The expressions of hippocampal GluR2 significantly increased in IBS‐like rats when compared with controls (p < .05). However, the levels of hippocampal GluR1 had no significant differences in rats. Hippocampal LTP induced by HFS was significantly enhanced when compared with controls (p < .05). The expressions of GluR2 significantly increased in the control and IBS‐like rats after 60 min LTP of recordings (p < .05), but not GluR1.ConclusionNeonatal maternal separation enhances the expression of GluR2 and facilitates the LTP in the hippocampus, which could lead to the formation of visceral hypersensitivity when grown up.
Cobalt‐Catalyzed Regioselective Borylation of Arenes: N‐Heterocyclic Silylene as an Electron Donor in the Metal‐Mediated Activation of C−H Bonds
Authors: Ren Hailong , Zhou Yu‐Peng , Bai Yunping , Cui Chunming , Driess Matthias 
Published: February 2017

AbstractC−H Borylation of arenes has been a subject of great interest recently because of its atom‐economy and the wide applicability of borylated products in value‐added synthesis. A new bis(silylene)cobalt(II) complex bearing a bis(N‐heterocyclic silylene)‐pyridine pincer ligand (SiNSi) has been synthesized and structurally characterized. It enabled the regioselective catalytic C−H borylation of pyridines, furans, and fluorinated arenes. Notably, it exhibited complementary regioselectivity for the borylation of fluorinated arenes compared to previously known catalytic systems, demonstrating that N‐heterocyclic silylene donors have enormous potential in metal‐catalyzed catalytic applications.
Adiponitrile–Lithium Bis(trimethylsulfonyl)imide Solutions as Alkyl Carbonate‐free Electrolytes for Li4Ti5O12 (LTO)/LiNi1/3Co1/3Mn1/3O2 (NMC) Li‐Ion Batteries
Authors: Farhat Douaa , Ghamouss Fouad , Maibach Julia , Edström Kristina , Lemordant Daniel 
Published: February 2017

AbstractRecently, dinitriles (NC(CH2)nCN) and especially adiponitrile (ADN, n=4) have attracted attention as safe electrolyte solvents owing to their chemical stability, high boiling points, high flash points, and low vapor pressure. The good solvation properties of ADN toward lithium salts and its high electrochemical stability (≈6 V vs. Li/Li+) make it suitable for safer Li‐ions cells without performance loss. In this study, ADN is used as a single electrolyte solvent with lithium bis(trimethylsulfonyl)imide (LiTFSI). This electrolyte allows the use of aluminium collectors as almost no corrosion occurs at voltages up to 4.2 V. The physicochemical properties of the ADN–LiTFSI electrolyte, such as salt dissolution, conductivity, and viscosity, were determined. The cycling performances of batteries using Li4Ti5O12 (LTO) as the anode and LiNi1/3Co1/3Mn1/3O2 (NMC) as the cathode were determined. The results indicate that LTO/NMC batteries exhibit excellent rate capabilities with a columbic efficiency close to 100 %. As an example, cells were able to reach a capacity of 165 mAh g−1 at 0.1 C and a capacity retention of more than 98 % after 200 cycles at 0.5 C. In addition, electrodes analyses by SEM, X‐ray photoelectron spectroscopy (XPS), and electrochemical impedance spectroscopy after cycling confirming minimal surface changes of the electrodes in the studied battery system.
Photoredox‐Catalyzed Isatin Reactions: Access to Dibenzo‐1,7‐Naphthyridine Carboxylate and Tryptanthrin
Authors: Sultan Shaista , Gupta Vivek , Shah Bhahwal Ali 
Published: February 2017

AbstractA procedure for the synthesis of dibenzo‐1,7‐naphthyridine carboxylate by means of photoredox catalysis has been developed. The reaction features an umpolung reaction of the keto group at the C‐3 position and entrapment of the decarbonylation‐prone C‐2 position of isatin. Additionally, the method is employed to showcase the chemodivergent behavior of isatins in aprotic solvents leading to the synthesis of tryptanthrin derivatives through photoredox catalysis. The reaction is demonstrated to be scalable (up to gram scale) and straightforward in terms of set up.
Low leopard populations in protected areas of Maputaland: a consequence of poaching, habitat condition, abundance of prey, and a top predator
Authors: Ramesh Tharmalingam , Kalle Riddhika , Rosenlund Havard , Downs Colleen T. 
Published: February 2017

AbstractIdentifying the primary causes affecting population densities and distribution of flagship species are necessary in developing sustainable management strategies for large carnivore conservation. We modeled drivers of spatial density of the common leopard (Panthera pardus) using a spatially explicit capture–recapture—Bayesian approach to understand their population dynamics in the Maputaland Conservation Unit, South Africa. We camera‐trapped leopards in four protected areas (PAs) of varying sizes and disturbance levels covering 198 camera stations. Ours is the first study to explore the effects of poaching level, abundance of prey species (small, medium, and large), competitors (lion Panthera leo and spotted hyenas Crocuta crocuta), and habitat on the spatial distribution of common leopard density. Twenty‐six male and 41 female leopards were individually identified and estimated leopard density ranged from 1.6 ± 0.62/100 km2 (smallest PA—Ndumo) to 8.4 ± 1.03/100 km2 (largest PA—western shores). Although dry forest thickets and plantation habitats largely represented the western shores, the plantation areas had extremely low leopard density compared to native forest. We found that leopard density increased in areas when low poaching levels/no poaching was recorded in dry forest thickets and with high abundance of medium‐sized prey, but decreased with increasing abundance of lion. Because local leopard populations are vulnerable to extinction, particularly in smaller PAs, the long‐term sustainability of leopard populations depend on developing appropriate management strategies that consider a combination of multiple factors to maintain their optimal habitats.
Chemical and nutritive characteristics of tree nut oils available in the U.S. market
Authors: Gong Yi , Pegg Ronald B. , Carr Elizabeth C. , Parrish Daniel R. , Kellett Mary E. , Kerrihard Adrian L. 
Published: February 2017

Tree nuts have become increasingly popular in the U.S. market due to their healthful fats and beneficial micronutrients and bioactives. The use of specialty tree nut oils has also been growing in popularity. As proper quality control measures are not currently in place, and published information on tree nut oils in the USDA National Nutrient Database for Standard Reference (SR28) is antiquated, an improved understanding of nut oil compositions could be of use to the industry and field. In this study, 20 commercially available brands of specialty tree nut oils, either imported or domestic, were analyzed to determine their contents of fatty acids, tocopherols (Ts), and phytosterols. While recent publications and the USDA Database confirm that γ‐T is the primary homolog endogenous to pecan oil, three of the four pecan oil samples tested were found to be most concentrated in α‐T. The T concentrations were also determined to be highly predictive of nut oil unsaturation (as summarized by calculated iodine values;  = 0.913), with the concentration of δ‐T presenting the greatest numeric weight to the model. The compositional information presented in this paper provides more in‐depth information on commercially available specialty tree nut oils.Practical applications: The information reported provides a better understanding of important compositional factors within tree nut oils, which can be of benefit to those that either produce or utilize such oils. These understandings are important to nutritional considerations, and may also inform the optimizations of processing and storage techniques. This study also contributes to our understanding of the relationship between endogenous T concentrations and oil unsaturation, which may improve our knowledge of antioxidative properties of Ts.Consumers are using tree nut oils in food preparations more frequently these days, partially due to the health benefits associated with these specialty oils. Limited research exists in nutritional databases about the lipid constituents – namely the fatty acids, phytosterols, and vitamin E contents – of these oils. This paper reports on the characterization of these constituents in raw and roasted tree nut oils available commercially.
Deletion of psychiatric risk gene Cacna1c impairs hippocampal neurogenesis in cell‐autonomous fashion
Authors: Völkening Bianca , Schönig Kai , Kronenberg Golo , Bartsch Dusan , Weber Tillmann 
Published: February 2017

AbstractCa2+ is a universal signal transducer which fulfills essential functions in cell development and differentiation. CACNA1C, the gene encoding the alpha‐1C subunit (i.e., Cav1.2) of the voltage‐dependent l‐type calcium channel (LTCC), has been implicated as a risk gene in a variety of neuropsychiatric disorders. To parse the role of Cav1.2 channels located on astrocyte‐like stem cells and their descendants in the development of new granule neurons, we created TgGLAST‐CreERT2/Cacna1cfl/fl/RCE:loxP mice, a transgenic tool that allows cell‐type‐specific inducible deletion of Cacna1c. The EGFP reporter was used to trace the progeny of recombined type‐1 cells. FACS‐sorted Cacna1c‐deficient neural precursor cells from the dentate gyrus showed reduced proliferative activity in neurosphere cultures. Moreover, under differentiation conditions, Cacna1c‐deficient NPCs gave rise to fewer neurons and more astroglia. Similarly, under basal conditions in vivo, Cacna1c gene deletion in type‐1 cells decreased type‐1 cell proliferation and reduced the neuronal fate‐choice decision of newly born cells, resulting in reduced net hippocampal neurogenesis. Unexpectedly, electroconvulsive seizures completely compensated for the proliferation deficit of Cacna1c deficient type‐1 cells, indicating that there must be Cav1.2‐independent mechanisms of controlling proliferation related to excitation. In the aggregate, this is the first report demonstrating the presence of functional L‐type 1.2 channels on type‐1 cells. Cav1.2 channels promote type‐1 cell proliferation and push the glia‐to‐neuron ratio in the direction of a neuronal fate choice and subsequent neuronal differentiation. Cav1.2 channels expressed on NPCs and their progeny possess the ability to shape neurogenesis in a cell‐autonomous fashion.
Unobserved selection heterogeneity and the gender wage gap
Authors: Machado Cecilia 
Published: February 2017

SummarySelection correction methods usually make assumptions about selection itself. In the case of gender wage gap estimation, those assumptions are especially tenuous because of high female nonparticipation and because selection could be different in different parts of the labor market. This paper proposes an estimator for the wage gap that allows for arbitrary and unobserved heterogeneity in selection. It applies to the subpopulation of “always employed” women, which is similar to men in labor force characteristics. Using CPS data from 1976 to 2005, I show that the gap has narrowed substantially from a −0.521 to a −0.263 log wage point differential for this population.
Dynamic spatial autoregressive models with autoregressive and heteroskedastic disturbances
Authors: Catania Leopoldo , Billé Anna Gloria 
Published: February 2017

SummaryWe propose a new class of models specifically tailored for spatiotemporal data analysis. To this end, we generalize the spatial autoregressive model with autoregressive and heteroskedastic disturbances, that is, SARAR(1, 1), by exploiting the recent advancements in score‐driven (SD) models typically used in time series econometrics. In particular, we allow for time‐varying spatial autoregressive coefficients as well as time‐varying regressor coefficients and cross‐sectional standard deviations. We report an extensive Monte Carlo simulation study in order to investigate the finite‐sample properties of the maximum likelihood estimator for the new class of models as well as its flexibility in explaining a misspecified dynamic spatial dependence process. The new proposed class of models is found to be economically preferred by rational investors through an application to portfolio optimization.
A dual‐label time‐resolved fluorescence immunoassay for the simultaneous determination of ferritin and β2‐microglobulin
Authors: Liu Zhi , Huang Jing , Ou Rui‐ming , Yao Meng‐dong , She Yan‐lin , Chen Rui , Li Cheng , Xu Li , Abudureyimu Aikebaier , Zhang Qing , Liu Shuang 
Published: February 2017

BackgroundLymphocytic leukemia is a kind of primary malignant tumor of hematopoietic tissue. The aim was to establish a dual‐label time‐resolved fluorescence immunoassay (TRFIA) for the simultaneous determination of ferritin (FER) and β2‐microglobulin (β2‐MG) for the early screening and follow‐up surveillance of lymphocytic leukemia.MethodsThe sandwich immunoassay was used to detect the concentration of FER, and the competitive immunoassay was used to detect the concentration of β2‐MG in serum. FER in serum was captured by anti‐ FER antibody immobilized on microtiter wells, and then banded together with another anti‐ FER labeled with europium(III) Eu3+ chelate, followed by fluorescence measurement using time‐resolved fluorometry (TRF). Sm3+ labeled β2‐MG and β2‐MG samples were added to compete with a certain amount of anti‐β2‐MG antibody, followed by fluorescence measurement using TRF. The performance of this dual‐label TRFIA was evaluated using the clinical blood and compared with the commercial assays.ResultsThe linear correlation coefficient (R2) of the FER and β2‐MG standard curves were 0.9914 and 0.9927, respectively. The sensitivity for FER detection was 8 ng/mL (dynamic range 0‐1000 ng/mL), the average recovery was 100.51%; The sensitivity for β2‐MG detection was 1 ng/mL (dynamic range 0‐1000 ng/mL), the average recovery was 101.02%. High correlation coefficients (R2) were obtained between the commercial assays (R2=.9966 for FER, and R2=.9897 for β2‐MG).ConclusionThe present dual‐label TRFIA has high sensitivity, specificity, and accuracy in clinical sample analysis. It is an effective detection method for the early screening and follow‐up surveillance of the acute and chronic lymphocytic leukemia.
Results of a phase II, open‐label, non‐comparative study of intralesional PV‐10 followed by radiotherapy for the treatment of in‐transit or metastatic melanoma
Authors: Foote Matthew , Read Tavis , Thomas Janine , Wagels Michael , Burmeister Bryan , Smithers B. Mark 
Published: February 2017

BACKGROUNDIn‐transit and recurrent dermal or subcutaneous melanoma metastases represent a significant burden of advanced disease. Intralesional Rose Bengal can elicit tumor selective ablation and a T‐cell mediated abscopal effect in untreated lesions. A subset of patients in a phase II trial setting received external beam radiotherapy to their recurrent lesions with complete or partial response and no significant acute radiation reaction.METHODSAn open‐label, single‐arm phase II study was performed to assess the efficacy and safety of PV‐10 followed by hypofractionated radiotherapy. Patients had in‐transit melanoma metastases suitable for IL therapy and radiotherapy.RESULTSFifteen patients were enrolled and thirteen completed both treatment components. The overall response rate was 86.6% and the clinical benefit was 93.3% on an intention to treat analysis (CR 33.3%, PR 53.3%, SD 6.7%). The median follow up duration was 19.25 months. Size of metastases (<10 mm) predicted lesion complete response (74.6%). Treatment was well tolerated with no associated grade 4 or 5 adverse events.CONCLUSIONSThe combination of PV‐10 and radiotherapy resulted in lesion‐specific, normal tissue‐sparing, ablation of disease with minimal local or systemic adverse effects.