bluuebunny/crossref_metadata_2025_split huggingface dataset:
The stratigraphy and evolution of lower Mount Sharp from spectral, morphological, and thermophysical orbital data sets
Authors: Fraeman A. A. , Ehlmann B. L. , Arvidson R. E. , Edwards C. S. , Grotzinger J. P. , Milliken R. E. , Quinn D. P. , Rice M. S. 
Published: August 2016

AbstractWe have developed a refined geologic map and stratigraphy for lower Mount Sharp using coordinated analyses of new spectral, thermophysical, and morphologic orbital data products. The Mount Sharp group consists of seven relatively planar units delineated by differences in texture, mineralogy, and thermophysical properties. These units are (1–3) three spatially adjacent units in the Murray formation which contain a variety of secondary phases and are distinguishable by thermal inertia and albedo differences, (4) a phyllosilicate‐bearing unit, (5) a hematite‐capped ridge unit, (6) a unit associated with material having a strongly sloped spectral signature at visible near‐infrared wavelengths, and (7) a layered sulfate unit. The Siccar Point group consists of the Stimson formation and two additional units that unconformably overlie the Mount Sharp group. All Siccar Point group units are distinguished by higher thermal inertia values and record a period of substantial deposition and exhumation that followed the deposition and exhumation of the Mount Sharp group. Several spatially extensive silica deposits associated with veins and fractures show that late‐stage silica enrichment within lower Mount Sharp was pervasive. At least two laterally extensive hematitic deposits are present at different stratigraphic intervals, and both are geometrically conformable with lower Mount Sharp strata. The occurrence of hematite at multiple stratigraphic horizons suggests redox interfaces were widespread in space and/or in time, and future measurements by the Mars Science Laboratory Curiosity rover will provide further insights into the depositional settings of these and other mineral phases.
Substrate Control in the Gold(I)‐Catalyzed Cyclization of β‐Propargylamino Acrylic Esters and Further Transformations of the Resultant Dihydropyridines
Authors: Mikušek Jiří , Matouš Petr , Matoušová Eliška , Janoušek Martin , Kuneš Jiří , Pour Milan 
Published: August 2016

AbstractN‐Protected β‐propargylamino acrylic esters with a push‐pull olefinic bond afforded good to high yields of dihydropyridines upon treatment with 5% tris(2‐furyl)phosphine‐gold(I) chloride/silver(I) tetrafluoroborate [(TFP)AuCl/AgBF4] in anhydrous benzene. Carbamate and sulfonyl groups were employed for nitrogen protection. On a model enyne, the p‐methoxybenzenesulfonyl (MBS) group was found to be a better protective group than tosyl in terms of cyclization yield, and also the yield of elimination to the corresponding 2,3,4‐trisubstituted pyridines. Boc‐protected dihydropyridines underwent partial deprotection/oxidation under the cyclization conditions, which enabled a more straightforward, one‐pot preparation of the corresponding pyridines. In another application, an appropriately substituted derivative protected as a stable methoxycarbamate was subjected to catalytic hydrogenation affording the known precursor of paroxetine. The chemoselectivity of enyne cyclization (dihydropyridine vs. pyrrole) is governed, among other factors, by C‐3 substitution. Dihydropyridines were obtained as sole products regardless of the catalyst/conditions when C‐3 was unsubstituted.magnified image
Copper‐Catalyzed C–N, C–O Coupling Reaction of Arylglyoxylic Acids with Isatins
Authors: Prakash Rashmi , Gogoi Sanjib 
Published: August 2016

AbstractThe copper(II)‐catalyzed decarboxylative coupling reactions of arylglyoxylic acids with isatins afford 4H‐benzo[d][1,3]oxazin‐4‐ones via decarbonylation and concurrent C–N, C–O bond formation.magnified image
Asymmetric Synthesis of Spiro β‐Lactams via a Squaramide‐ Catalyzed Sulfa‐Michael Addition/Desymmetrization Protocol
Authors: Chauhan Pankaj , Mahajan Suruchi , Kaya Uğur , Valkonen Arto , Rissanen Kari , Enders Dieter 
Published: August 2016

AbstractAn efficient asymmetric synthesis of spirocyclohexenone β‐lactams bearing three contiguous stereocenters has been achieved in moderate to good yields and high stereoselectivities. The protocol involves the combination of a squaramide‐catalyzed sulfa‐Michael addition under desymmetrization via a dynamic kinetic resolution of racemic 2,5‐cyclohexadienones.magnified image
Scalable Production of Multifunctional Bio‐Based Polyamide 11/Graphene Nanocomposites by Melt Extrusion Processes Via Masterbatch Approach
Authors: Rashmi B. J. , Prashantha K. , Lacrampe M.‐F. , Krawczak P. 
Published: August 2016

AbstractBio‐based polyamide 11 (PA11)–graphene nanoplatelets (GNP) nanocomposites with different filler concentrations were prepared by melt extrusion using a masterbatch dilution process. Graphene platelets are uniformly distributed into the polymer matrix as revealed by scanning electron microscopy. The incorporation of graphene significantly improves the electrical conductivity and dielectric constant of PA11. GNPs favors the matrix crystallization; crystallization temperature and degree of crystallinity of the nanocomposites tend to increase with increase in graphene loading. Tensile properties (strength and modulus) are slightly improved by the incorporation of GNP into the PA11 matrix (up to +25% and +56%, respectively, for 5 wt% GNPs) at the expense of ductility (elongation at break divided by 5 for 5 wt% GNPs).
Ionic liquids in supercritical methanol greatly enhance transesterification reaction for high‐yield biodiesel production
Authors: Ortiz‐Martínez V. M. , Salar‐García M. J. , Hernández‐Fernández F. J. , Olivares‐Carrillo P. , de los Ríos A. P. , Quesada‐Medina J. 
Published: August 2016

SignificanceBiodiesel production is one of the most promising future alternatives to replacing fossil fuels. This work studies the use of ionic liquids (ILs) as potential catalysts in supercritical methanol for biodiesel production from non‐edible oil. The transesterification reaction of karanja oil was investigated in supercritical methanol in the presence of two respective ILs, [BMIM+][
] and [Chol+][H2
]. The reaction was performed in a one‐step batch process at several temperatures and percentages by weight of catalyst (w/woil). The results obtained show that the IL [Chol+][H2
] allows a high yield of fatty acid methyl esters to be achieved in a short reaction time (above 95% in 45 min). A catalytic mechanism is also proposed for the IL that offered significant catalytic activity. This work investigates the effects of the use of ionic liquids as potential catalysts in supercritical methanol for the transesterification reaction of non‐edible oil. The reported reaction times to obtain biodiesel yields above 90% through the transesterification reaction of karanja oil range between 90 min and 8 h. ILs as catalysts in supercritical methanol drastically reduce reaction time (45 min) to obtain high fatty acid methyl ester yield (95.6%). © 2016 American Institute of Chemical Engineers AIChE J, 62: 3842–3846, 2016
Stereoselective Alkylation of Imines and its Application towards the Synthesis of β‐Lactams
Authors: Goyal Sandeep , Thakur Anamika , Sharma Ratnesh , Gangar Mukesh , Patel Bhautikkumar , Nair Vipin A. 
Published: August 2016

Abstract(S)‐4‐Isopropyl‐1‐[(R)‐1‐phenylethyl]imidazolidin‐2‐one was evaluated as a chiral auxiliary for asymmetric acetate and propionate Mannich‐type reactions, by generation of the titanium enolates, affording excellent yields and stereoselectivities. The application of the auxiliary was exemplified in the stereoselective synthesis of the β‐lactam antihyperlipidemic drug ezetimibe.
Protonation‐Driven Membrane Insertion of a pH‐Low Insertion Peptide
Authors: Hanz Samuel Z. , Shu Nicolas S. , Qian Jieni , Christman Nathaniel , Kranz Patrick , An Ming , Grewer Christof , Qiang Wei 
Published: August 2016

AbstractThe pH‐low insertion peptide (pHLIP) inserts into membranes and forms a transmembrane (TM) α‐helix in response to slight acidity, and has shown great potential for cancer diagnosis and treatment. As a lead, pHLIP is challenging to optimize because the mechanism of its pH‐dependent membrane interactions is not completely understood. Within pHLIP there are multiple D/E residues which could sense the pH change, the particular role played by each of them in the protonation‐driven insertion process is not clear. The precise location of the TM helix within the pHLIP sequence is also unknown. In this work, solid‐state NMR spectroscopy is used to address these central questions. Tracing backbone conformations revealed that the TM helix spans from A10 to D33 with a break at T19 to P20. Residue‐specific pKa values of D31, D33, D25, and D14 were determined to be 6.5, 6.3, 6.1, and 5.8, respectively, and define the sequence of protonations which lead to insertion. Furthermore, possible intermediate states which disrupt membranes at pH 6.4 were proposed based on tryptophan fluorescence quenching and NMR data.
Clickable Poly(ionic liquids): A Materials Platform for Transfection
Authors: Freyer Jessica L. , Brucks Spencer D. , Gobieski Graham S. , Russell Sebastian T. , Yozwiak Carrie E. , Sun Mengzhen , Chen Zhixing , Jiang Yivan , Bandar Jeffrey S. , Stockwell Brent R. , Lambert Tristan H. , Campos Luis M. 
Published: August 2016

AbstractThe potential applications of cationic poly(ionic liquids) range from medicine to energy storage, and the development of efficient synthetic strategies to target innovative cationic building blocks is an important goal. A post‐polymerization click reaction is reported that provides facile access to trisaminocyclopropenium (TAC) ion‐functionalized macromolecules of various architectures, which are the first class of polyelectrolytes that bear a formal charge on carbon. Quantitative conversions of polymers comprising pendant or main‐chain secondary amines were observed for an array of TAC derivatives in three hours using near equimolar quantities of cyclopropenium chlorides. The resulting TAC polymers are biocompatible and efficient transfection agents. This robust, efficient, and orthogonal click reaction of an ionic liquid, which we term ClickabIL, allows straightforward screening of polymeric TAC derivatives. This platform provides a modular route to synthesize and study various properties of novel TAC‐based polymers.
Molecular Conductance through a Quadruple‐Hydrogen‐Bond‐Bridged Supramolecular Junction
Authors: Wang Lin , Gong Zhong‐Liang , Li Shu‐Ying , Hong Wenjing , Zhong Yu‐Wu , Wang Dong , Wan Li‐Jun 
Published: August 2016

AbstractA series of self‐complementary ureido pyrimidinedione (UPy) derivatives modified with different aurophilic anchoring groups were synthesized. Their electron transport properties through the quadruple hydrogen bonds in apolar solvent were probed employing the scanning tunneling microscopy break junction (STMBJ) technique. The molecule terminated with a thiol shows the optimal electron transport properties, with a statistical conductance value that approaches 10−3 G0. The 1H NMR spectra and control experiments verify the formation of quadruple hydrogen bonds, which can be effectively modulated by the polarity of the solvent environment. These findings provide a new design strategy for supramolecular circuit elements in molecular electronics.
Aminopyridinyl–Pseudodeoxycytidine Derivatives Selectively Stabilize Antiparallel Triplex DNA with Multiple CG Inversion Sites
Authors: Okamura Hidenori , Taniguchi Yosuke , Sasaki Shigeki 
Published: August 2016

AbstractThe sequence‐specific formation of triplex DNA offers a potential basis for genome‐targeting technologies. In an antiparallel triplex DNA, the sequence‐specificity is established by the formation of specific base triplets (G−GC, A−AT, and T−AT) between a triplex‐forming oligonucleotide (TFO) and a duplex DNA. However, there are no natural nucleosides that can selectively recognize the inverted CG and TA base pairs. Therefore, the recognition of the CG and TA inversion sites to form a stable triplex DNA has been a long‐standing goal for the triplex‐forming technology. We now describe the design and synthesis of pseudo‐deoxycytidine (ΨdC) derivatives for selective recognition of the CG base pair to expand the triplex‐forming sequence. The aminopyridine‐bearing ΨdC derivatives showed high selectivity and affinity toward the CG base pair in all neighboring base contexts. Remarkably, 3‐methyl‐2‐aminopyridinyl−ΨdC (MeAP−ΨdC) formed a stable triplex with the promoter sequence of the hTERT gene containing four CG inversion sites, and effectively inhibited its transcription in human cancer cells. Thus, MeAP−ΨdC is expected to serve as a new starting point of triplex‐forming oligonucleotides for a wide variety of genome‐targeting applications.
Habitat recovery and restoration in aquatic ecosystems: current progress and future challenges
Authors: Geist Juergen , Hawkins Stephen J. 
Published: August 2016

Abstract

Aquatic ecosystems are degraded by a variety of pressures as a result of the growing human population. Global‐scale impacts include homogenization of biological communities, removal of top predators and ecosystem engineers, chemical pollution by excess nutrients and contaminants as well as deteriorating structural diversity, connectivity and process dynamics. There is a pressing societal need to reverse the decline in biodiversity and replace lost ecosystem functioning and services in aquatic ecosystems by enabling natural recovery or by active restoration.
Common concepts and approaches for conservation, recovery and restoration in freshwater and marine ecosystems, aided by recent advances in ecological theory, include decision criteria on priorities for conservation, harnessing natural recovery by cessation of impacts, restoring connectivity and meso‐habitat diversity as well as the geomorphological structural template including hydrodynamic processes. Re‐oligotrophication at catchment or regional sea‐scale benefits from integrating freshwater and marine restoration. Species or assemblages that convey biogenic structure or act as ecosystem engineers and keystone species should be given priority. Top‐down control can be reinstated in closed systems.
Differences between freshwater and marine ecosystems include the greater spatial restriction of many species in fresh water, the importance of rooted vegetation and insects in freshwater, and the much greater dispersal and connectivity in marine systems. These differences dictate different approaches, with more scope for active restoration work in fresh water and harnessing natural recovery in marine systems.
Restoration schemes need clearly defined target states. They should generally take a process‐oriented and stepwise adaptive management approach judging success against reference or control sites. Societal and political expectations need to be managed and restoration schemes should not promise too much. Even minor rehabilitation of degraded ecosystems can put back some biodiversity and key services. Sometimes ´Ersatz´‐ecosystems are better than nothing and the best that can be achieved, especially in urban settings.
Copyright © 2016 John Wiley & Sons, Ltd.
Geophysical and Archaeological Evidences of Buried Epipalaeolithic, Neolithic, Bronze Age and Roman Architecture in West‐Central Syria
Authors: Himi Mahjoub , Armendariz Angel , Teira Luis , González Jesus , Ibáñez Juan José , Haïdar‐Boustani Maya , Casas Albert 
Published: August 2016

AbstractThe study area is one of many important archaeological sites located near the city of Homs in Syria. Here, the existence of archaeological remains was studied using two complementary geophysical methods: ground‐penetrating radar (GPR) and electrical resistivity tomography (ERT). The results provide evidence of localized buried remains and allowed detailed pre‐excavation planning. Furthermore, the later archaeological excavations validated the results obtained from the GPR and ERT surveys. In some areas, the presence of moist clayey soils caused significant attenuation of the radar signal. Conversely, under these circumstances, the contrast in electrical resistivity between natural soil and archaeological targets is enhanced and thus the ERT results identified the archaeological remains.Many two‐dimensional (2D) profiles showed a set of high relative resistivity values depicting well‐defined discontinuous structures within the first 2 m of depth. Nevertheless, their geometrical distribution and shape was much more clearly defined in the depth slice maps generated from the three‐dimensional (3D) blocks. As a result, data analysis provided a high‐resolution image of the subsurface distribution of the electrical resistivity properties of each area surveyed that can easily be interpreted in terms of structures of archaeological interest. Copyright © 2016 John Wiley & Sons, Ltd.
Solid Amine Adsorbent Prepared by Molecular Imprinting and Its Carbon Dioxide Adsorption Properties
Authors: He Hui , Zhuang Linzhou , Chen Shuixia , Liu Hucheng 
Published: August 2016

AbstractA carbon dioxide imprinted solid amine adsorbent (IPEIA‐R) with polyethylenimine (PEI) as a skeleton was conveniently prepared by using glutaraldehyde to cross‐link carbon dioxide‐preadsorbed PEI. As confirmed by FTIR, FT‐Raman, and 13C NMR spectroscopy, CO2 preadsorbed on PEI could occupy the reactive sites of amino groups and act as a template for imprinting in the cross‐linking process. The imino groups formed from the cross‐linking reaction between glutaraldehyde and PEI could be reduced by NaBH4 to form CO2‐adsorbable amino groups. The adsorption results indicated that CO2 imprinting and reduction of imino groups by NaBH4 endowed the adsorbent with a higher CO2 adsorption capacity. Compared with PEI‐supported mesoporous adsorbents, the solid amine adsorbent with PEI as a skeleton can avoid serious pore blockage and CO2 diffusion resistance, even with a high amine content. The solid amine adsorbent with PEI as a skeleton showed a remarkable CO2 adsorption capacity (8.56 mmol g−1) in the presence of water at 25 °C, owing to the high amine content and good swelling properties. It also showed promising regeneration performance and could maintain almost the same CO2 adsorption capacity after 15 adsorption–desorption cycles.
Cover Image, Volume 10, Issue 5
Authors: Bezerra Tais Lacerda , Ragauskas Art J. 
Published: August 2016

The cover image, by Arthur J. Ragauskas and Tais Lacerda Bezerra, is based on the Review A review of sugarcane bagasse for second‐generation bioethanol and biopower production, DOI: 10.1002/bbb.1662. Photo Courtesy: NREL image gallery and USDA/ARS image gallery.
image
Fabrication of multilayered vascular tissues using microfluidic agarose hydrogel platforms
Authors: Kinoshita Keita , Iwase Masaki , Yamada Masumi , Yajima Yuya , Seki Minoru 
Published: August 2016

AbstractVascular tissues fabricated in vitro are useful tools for studying blood vessel‐related cellular physiologies and for constructing relatively large 3D tissues. An efficient strategy for fabricating vascular tissue models with multilayered, branched, and thick structures through the in situ hydrogel formation in fluidic channels is proposed. First, an aqueous solution of RGD‐alginate containing smooth muscle cells (SMCs) is introduced into channel structures made of agarose hydrogel, forming a cell‐embedding Ca‐alginate hydrogel layer with a thickness of several hundred micrometers on the channel surface because of the Ca2+ ions diffused from the agarose hydrogel matrix. Next, endothelial cells (ECs) are introduced and cultured for up to seven days to form hierarchically organized, multilayered vascular tissues. The factors affecting the thickness of the Ca‐alginate hydrogel layer, and prepared several types of microchannels with different morphologies are examined. The fabricated vascular tissue models are easily recovered from the channel by simply detaching the agarose hydrogel plates. In addition, the effect of O2 tension (20 or 80%) on the viability and elastin production of SMCs during the perfusion culture is evaluated. This technique would pave a new way for vascular tissue engineering because it enables the facile production of morphologically in vivo vascular tissue‐like structures that can be employed for various biomedical applications.
Enhanced cellulase production from Trichoderma reesei Rut‐C30 by engineering with an artificial zinc finger protein library
Authors: Zhang Fei , Bai Fengwu , Zhao Xinqing 
Published: August 2016

AbstractTrichoderma reesei Rut‐C30 is a well‐known cellulase producer, and improvement of its cellulase production is of great interest. An artificial zinc finger protein (AZFP) library is constructed for expression in T. reesei Rut‐C30, and a mutant strain T. reesei U3 is selected based on its enhanced cellulase production. The U3 mutant shows a 55% rise in filter paper activity and 8.1‐fold increased β‐glucosidase activity, when compared to the native strain T. reesei Rut‐C30. It is demonstrated that enhanced β‐glucosidase activity was due to elevated transcription level of β‐glucosidase gene in the U3 mutant. Moreover, significant elevation in transcription levels of several putative Azfp‐U3 target genes is detected in the U3 mutant, including genes encoding hypothetical transcription factors and a putative glycoside hydrolase. Furthermore, U3 cellulase shows 115% higher glucose yield from pretreated corn stover, when compared to the cellulase of T. reesei Rut‐C30. These results demonstrate that AZFP can be used to improve cellulase production in T. reesei Rut‐C30. Our current work offers the establishment of an alternative strategy to develop fungal cell factories for improved production of high value industrial products.
Gender Diversity on Boards and Firms’ Environmental Policy
Authors: Li Ji , Zhao Fuqiang , Chen Silu , Jiang Wanxing , Liu Tao , Shi Shengping 
Published: August 2016

AbstractThis paper tests the relationship between gender diversity on boards and firms’ environmental policy. Based on prior research, we predict that gender diversity on boards of directors should have a positive relationship with firms’ environmental policy. Moreover, firm character in terms of pollution creation likelihood moderates the relationship between gender diversity on boards and firms’ environmental policy. Analyzing data from 865 publicly listed firms in the United States, we found direct and significant empirical evidence for our predictions. According to the findings, we highlight the importance of gender diversity for the development of good firm environmental policy as well as for the improvement of corporate governance. Moreover, the more likely firms in a given industry are to cause environmental pollution, the more salient will be the beneficial effect of gender diversity on boards on firms’ environmental policy in the industry. Copyright © 2016 John Wiley & Sons, Ltd and ERP Environment
Sustainable Entrepreneurship and B Corps
Authors: Stubbs Wendy 
Published: August 2016

AbstractSustainable entrepreneurship contributes to solving social and environmental problems through the means of successful for‐profit businesses. This paper contributes to understanding how sustainable entrepreneurship is implemented by exploring an emerging new form of business, ‘B Corps’, that employs market tactics to address social and environmental issues. Through interviewing 14 B Corps, the exploratory research study found that B Corps treat profit as a means to achieve positive societal ends, they regard the B Corp model as a tool for change, the B Corp model provides a common collective identity for internal and external validation, they are focused on societal impact rather than maximizing profits and they attempt to legitimate this form of sustainable entrepreneurship by influencing the business community and government officials. Copyright © 2016 John Wiley & Sons, Ltd and ERP Environment