bluuebunny/crossref_metadata_2025 huggingface dataset:
Farmers’ preference for bundled input–output markets and implications for adapted dairy hubs in Tanzania—A choice experiment
Authors: Rao Elizaphan J.O. , Mtimet N. , Twine E. , Baltenweck I. , Omore A.
Published: June 2018

Dairy business hubs (DBHs) are flexible mechanisms for linking farmers to input and output markets. Yet participation by smallholders in these hubs will only be realized if the hub options are adapted to the needs of farmers. We analyze preference for DBHs in Tanzania using survey data from smallholder dairy producers in Tanga and Morogoro. Applying choice experiment method, we find significant preference for hub options with higher milk prices and payment for milk on a fortnight rather than cash basis. Farmers also prefer options that bundle milk marketing with input provision. For bundled inputs, farmers prefer hub options that allow payment for such inputs via credit or check‐off rather than cash. Our analyses also reveal significant heterogeneity in preference among farmers that should be considered in adapting dairy hubs to Tanzania. Emerging dairy hubs in Tanzania should be supported to either establish in‐house input provision arrangements or to enter contracts with agro‐input dealers in their environs. [EconLit citations: C25, C99, Q13]
Price transmission dynamics for quality‐certified food products: A comparison between conventional and organic fluid milk in Italy
Authors: Antonioli Federico , Ben Kaabia Monia , Arfini Filippo , Gil José M.
Published: June 2018

Despite the vast number of works investigating price transmission (PT) processes in diverse agrifood markets, very little has been said about quality‐differentiated products. In this paper, we compare the conventional and organic fluid milk sectors in Italy to better understand the economic organization and functioning of one of the most important agrifoods in Italy. Using a unique dataset featuring processor and retail (scanner) prices for the two types of milk, we estimate Momentum‐Threshold Autoregressive models to account for asymmetric price movements in both sectors, but the PT results are eventually symmetric. The Vector Error Correction Model estimations and Impulse Response Functions analysis provide significant insights into the differences between the two markets. [EconLit citations: Q130, Q110, C590]
Modeling of thermodynamics of substituted toluene derivatives and benzylic radicals via group additivity
Authors: Ince Alper , Carstensen Hans‐Heinrich , Sabbe Maarten , Reyniers Marie‐Françoise , Marin Guy B.
Published: June 2018

The thermodynamic properties of unsubstituted, mono‐, and di‐substituted toluene derivatives and benzylic radicals with hydroxy, methoxy, formyl, vinyl, methyl, and ethyl substituents are calculated with the bond additivity corrected (BAC) post‐Hartree‐Fock CBS‐QB3 method. Benson's group additivity (GA) scheme is extended to toluene derivatives by determining six group additive value (GAV) and five non‐nearest neighbor interaction (NNI) parameters through least‐squares regression to a database of thermodynamic properties of 168 compounds and to benzylic radicals by defining 6 GAV and 14 NNI parameters based on a set of 168 radicals. Comparison between CBS‐QB3/BAC and GA‐calculated thermodynamic values shows that the standard enthalpies of formation generally agree within 4 kJ mol−1, whereas the entropies and the heat capacities generally deviate <4 J mol−1 K−1. © 2018 American Institute of Chemical Engineers AIChE J, 64: 3649–3661, 2018
Fentanyls and the safety of first responders: Science and recommendations
Authors: Howard John , Hornsby‐Myers Jennifer
Published: June 2018

Opioids have many beneficial uses in medicine, but, taken inappropriately, they can cause life‐threatening health effects. The increasing use of physician‐prescribed and illicit opioids, including highly potent fentanyl and its analogs, have contributed to a significant increase in opioid‐related drug overdoses in the United States, leading to a public health emergency. There have been a number of reports describing adverse health effects experienced by police officers, fire‐fighter emergency medical services providers, and private sector ambulance personnel when responding to drug overdose incidents. Several sets of exposure prevention recommendations for first responders are available from government and the private sector. Understanding the scientific basis for these recommendations, increasing awareness by responders of the potential risks associated with opioid exposure during a response, and educating responders about safe work practices when exposure to opioids is suspected or confirmed are all critical prevention measures that can keep first responders safe.
RhI‐Catalyzed Intramolecular [3+2] Cycloaddition of 1‐Allene‐vinylcyclopropanes
Authors: Liu Cheng‐Hang , Li Feng , Yuan Yuan , Dou Meng , Yu Zhi‐Xiang
Published: June 2018

A rhodium‐catalyzed intramolecular [3+2] cycloaddition of 1‐allene‐vinylcyclopropanes (1‐allene‐VCPs) to construct cyclopentane‐embedded bicyclic structures with quaternary stereocenters at the bridgehead position has been developed with good to excellent yields. In addition, this transformation could also be conducted on a large scale with reduced catalyst loading, which could be useful for further derivatizations and applications.
The Existence of Nitrate Radicals in Irradiated TiO2 Aqueous Suspensions in the Presence of Nitrate Ions
Authors: Parrino Francesco , Livraghi Stefano , Giamello Elio , Palmisano Leonardo
Published: June 2018

Evidence of the existence of nitrate radical in irradiated aqueous TiO2 suspensions in the presence of nitrate ions are reported for the first time. The joint use of UV/Vis and EPR spectroscopy showed that nitrate radicals are formed by hole induced oxidation of nitrate ions. Photocatalytic degradation of a model alkene compound allowed to highlight the presence of an intermediate organic nitrate deriving from nitrate radical attack to the double bond of the substrate. These results not only allow deeper understanding of photocatalytic processes, but open the route to new green photocatalytic syntheses initiated by nitrate radicals and to new insights in the field of atmospheric chemistry.
Über bisherige Denkweisen hinaus – neue Wirkstoffe zur Überwindung der Antibiotika‐Krise
Authors: Lakemeyer Markus , Zhao Weining , Mandl Franziska A. , Hammann Peter , Sieber Stephan A.
Published: June 2018

Die öffentliche Wahrnehmung von Antibiotika als verlässliche Arzneimittel veränderte sich drastisch, als Meldungen über “multiresistente Super‐Erreger” die Nachrichten aufrüttelten. Während die Ursachen für die bakterielle Resistenzentwicklung schnell erkannt wurden, befindet sich die Forschung zur Wiedergewinnung von Antibiotika als effektive Arzneistoffe immer noch am Anfang. Dieser Aufsatz umfasst zahlreiche Aspekte des Entwicklungsprozesses neuer Antibiotika, von der Grundlagenforschung bis zum fertigen Medikament. Er bietet einen interdisziplinären Überblick über Methoden zur Identifizierung neuer Antibiotika und erörtert Strategien, um ihren molekularen Wirkmechanismus aufzuklären. Die Darstellung ausgewählter Antibiotika, die kürzlich mithilfe dieser Plattformen entdeckt wurden, verdeutlicht die Effizienz der Ansätze und hebt vielversprechende klinische Kandidaten mit therapeutischem Potential hervor. Zusätzlich wird das Konzept von Molekülen erörtert, die Krankheitserreger “entwaffnen”, indem sie Schlüsselpunkte der Virulenz adressieren. Der Aufsatz schließt mit einer kritischen Beurteilung jener antibakteriellen Wirkstoffe, die sich derzeit in klinischer Entwicklung befinden. Insgesamt soll dieser Aufsatz ausgewählte, innovative antibakterielle Ansätze verknüpfen, um interdisziplinäre Partnerschaften zwischen Chemikern aus der akademischen und industriellen Forschung anzuregen.
Nonlinear Unmixing of Hyperspectral Datasets for the Study of Painted Works of Art
Authors: Rohani Neda , Pouyet Emeline , Walton Marc , Cossairt Oliver , Katsaggelos Aggelos K.
Published: June 2018

Nonlinear unmixing of hyperspectral reflectance data is one of the key problems in quantitative imaging of painted works of art. The approach presented is to interrogate a hyperspectral image cube by first decomposing it into a set of reflectance curves representing pure basis pigments and second to estimate the scattering and absorption coefficients of each pigment in a given pixel to produce estimates of the component fractions. This two‐step algorithm uses a deep neural network to qualitatively identify the constituent pigments in any unknown spectrum and, based on the pigment(s) present and Kubelka–Munk theory to estimate the pigment concentration on a per‐pixel basis. Using hyperspectral data acquired on a set of mock‐up paintings and a well‐characterized illuminated folio from the 15th century, the performance of the proposed algorithm is demonstrated for pigment recognition and quantitative estimation of concentration.
Ultrafast Iron‐Catalyzed Reduction of Functionalized Ketones: Highly Enantioselective Synthesis of Halohydrines, Oxaheterocycles, and Aminoalcohols
Authors: Blasius Clemens K. , Vasilenko Vladislav , Gade Lutz H.
Published: June 2018

A molecularly defined chiral boxmi iron alkyl complex catalyzes the hydroboration of various functionalized ketones and provides the corresponding chiral halohydrines, oxaheterocycles (oxiranes, oxetanes, tetrahydrofurans, and dioxanes) and amino alcohols with excellent enantioselectivities (up to >99 %ee) and conversion efficiencies at low catalyst loadings (as low as 0.5 mol %). Turnover frequencies of greater than 40000 h−1 at −30 °C highlight the activity of this earth‐abundant metal catalyst which tolerates a large number of functional groups.
A Platinum(II) Complex of Heptamethine Cyanine for Photoenhanced Cytotoxicity and Cellular Imaging in Near‐IR Light
Authors: Mitra Koushambi , Lyons Charles E. , Hartman Matthew C. T.
Published: June 2018

Controlled generation of cytotoxic agents with near‐IR light is a current focus of photoactivated cancer therapy, including that involving cytotoxic platinum species. A heptamethine cyanine scaffolded PtII complex, IR797‐Platin exhibits unprecedented Pt−O bond scission and enhancement in DNA platination in near‐IR light. This complex also displayed significant singlet oxygen quantum yield thereby qualifying as a near‐IR photodynamic therapeutic agent. The complex showed 30–60 fold enhancement of cytotoxicity in near‐IR light in various cancer cell lines. The cellular imaging properties were also leveraged to observe its significant co‐localization in cytoplasmic organelles. This is the first demonstration of a near‐IR light‐initiated therapy involving the cytotoxic effects of both active cisplatin and singlet oxygen.
Enhanced Cytosolic Delivery and Release of CRISPR/Cas9 by Black Phosphorus Nanosheets for Genome Editing
Authors: Zhou Wenhua , Cui Haodong , Ying Liming , Yu Xue‐Feng
Published: June 2018

A biodegradable two‐dimensional (2D) delivery platform based on loading black phosphorus nanosheets (BPs) with Cas9 ribonucleoprotein engineered with three nuclear localization signals (NLSs) at C terminus (Cas9N3) is successfully established. The Cas9N3‐BPs enter cells effectively via membrane penetration and endocytosis pathways, followed by a BPs biodegradation‐associated endosomal escape and cytosolic releases of the loaded Cas9N3 complexes. The Cas9N3‐BPs thus provide efficient genome editing and gene silencing in vitro and in vivo at a relatively low dose as compared with other nanoparticle‐based delivery platforms. This biodegradable 2D delivery platform offers a versatile cytosolic delivery approach for CRISPR/Cas9 ribonucleoprotein and other bioactive macromolecules for biomedical applications.
A Simple, Broad‐Scope Nickel(0) Precatalyst System for the Direct Amination of Allyl Alcohols
Authors: Sweeney Joseph B. , Ball Anthony K. , Lawrence Philippa A. , Sinclair Mackenzie C. , Smith Luke J.
Published: June 2018

The preparation of allylic amines is traditionally accomplished by reactions of amines with reactive electrophiles, such as allylic halides, sulfonates, or oxyphosphonium species; such methods involve hazardous reagents, generate stoichiometric waste streams, and often suffer from side reactions (such as overalkylation). We report here the first broad‐scope nickel‐catalysed direct amination of allyl alcohols: An inexpensive NiII/Zn couple enables the allylation of primary, secondary, and electron‐deficient amines without the need for glove‐box techniques. Under mild conditions, primary and secondary aliphatic amines react smoothly with a range of allyl alcohols, giving secondary and tertiary amines efficiently. This “totally catalytic” method can also be applied to electron‐deficient nitrogen nucleophiles; the practicality of the process was demonstrated in an efficient, gram‐scale preparation of the calcium antagonist drug substance flunarizine (Sibelium®).
Chirality Enhancement of Porphyrin Supramolecular Assembly Driven by a Template Preorganization Effect
Authors: Gaeta Massimiliano , Raciti Domenica , Randazzo Rosalba , Gangemi Chiara M. A. , Raudino Antonio , D'Urso Alessandro , Fragalà Maria E. , Purrello Roberto
Published: June 2018

Cationic polylysine promotes, under neutral conditions, the spontaneous aggregation of opposite charged ZnTPPS in water. Spectroscopic investigations evidence a different preorganization of ZnTPPS onto the polypeptide matrix depending on the chain length. Spinodal decomposition theory in confined geometry is used to model this mechanism by considering the time evolution of a homogeneous distribution of randomly adsorbed particles (porphyrins) onto a rodlike polyelectrolyte (polymer) of variable length L.
Cells in the Non‐Uniform Magnetic World: How Cells Respond to High‐Gradient Magnetic Fields
Authors: Zablotskii Vitalii , Polyakova Tatyana , Dejneka Alexandr
Published: June 2018

Imagine cells that live in a high‐gradient magnetic field (HGMF). Through what mechanisms do the cells sense a non‐uniform magnetic field and how such a field changes the cell fate? We show that magnetic forces generated by HGMFs can be comparable to intracellular forces and therefore may be capable of altering the functionality of an individual cell and tissues in unprecedented ways. We identify the cellular effectors of such fields and propose novel routes in cell biology predicting new biological effects such as magnetic control of cell‐to‐cell communication and vesicle transport, magnetic control of intracellular ROS levels, magnetically induced differentiation of stem cells, magnetically assisted cell division, or prevention of cells from dividing. On the basis of experimental facts and theoretical modeling we reveal timescales of cellular responses to high‐gradient magnetic fields and suggest an explicit dependence of the cell response time on the magnitude of the magnetic field gradient.
Enhanced production of poly‐γ‐glutamic acid by improving ATP supply in metabolically engineered Bacillus licheniformis
Authors: Cai Dongbo , Chen Yaozhong , He Penghui , Wang Shiyi , Mo Fei , Li Xin , Wang Qin , Nomura Christopher T. , Wen Zhiyou , Ma Xin , Chen Shouwen
Published: June 2018

Poly‐γ‐glutamic acid (γ‐PGA) is an important multifunctional biopolymer with various applications, for which adenosine triphosphate (ATP) supply plays a vital role in biosynthesis. In this study, the enhancement of γ‐PGA production was attempted through various approaches of improving ATP supply in the engineered strains of Bacillus licheniformis. The first approach is to engineer respiration chain branches of B. licheniformis, elimination of cytochrome bd oxidase branch reduced the maintenance coefficient, leading to a 19.27% increase of γ‐PGA yield. The second approach is to introduce Vitreoscilla hemoglobin (VHB) into recombinant B. licheniformis, led to a 13.32% increase of γ‐PGA yield. In the third approach, the genes purB and adK in ATP‐biosynthetic pathway were respectively overexpressed, with the AdK overexpressed strain increased γ‐PGA yield by 14.69%. Our study also confirmed that the respiratory nitrate reductase, NarGHIJ, is responsible for the conversion of nitrate to nitrite, and assimilatory nitrate reductase NasBC is for conversion of nitrite to ammonia. Both NarGHIJ and NasBC were positively regulated by the two‐component system ResD–ResE, and overexpression of NarG, NasC, and ResD also improved the ATP supply and the consequent γ‐PGA yield. Based on the above individual methods, a method of combining the deletion of cydBC gene and overexpression of genes vgB, adK, and resD were used to enhance ATP content of the cells to 3.53 μmol/g of DCW, the mutant WX‐BCVAR with this enhancement produced 43.81 g/L of γ‐PGA, a 38.64% improvement compared to wild‐type strain WX‐02. Collectively, our results demonstrate that improving ATP content in B. licheniformis is an efficient strategy to improve γ‐PGA production.
Vascularized microfluidic platforms to mimic the tumor microenvironment
Authors: Michna Rhys , Gadde Manasa , Ozkan Alican , DeWitt Matthew , Rylander Marissa
Published: June 2018

Microfluidic technology has led to the development of advanced in vitro tumor platforms that overcome the challenges of in vivo animal and in vitro two dimensional models. This paper presents platform designs and methods used to develop complex vascularized in vitro models to mimic the tumor microenvironment. Features of these platforms include a continuous, aligned endothelium that allows for cell‐cell interactions between vasculature and tumor cells. A novel platform for fabrication of a single endothelialized microchannel encased within a collagen platform hosting breast cancer cells was developed and utilized to study the influence of cellular interaction on transport phenomenon through vasculature in a hyperpermeable tumor microenvironment. This platform relies on subtractive tissue engineering fabrication techniques. Through confocal imaging we have demonstrated that the platform produces enhanced vessel leakiness recapitulating physiological features of the tumor microenvironment. The influence of tumor endothelial interactions on transport of particles was also demonstrated. Additionally, we designed two more complex and intricate endothelialized microfluidic networks by combining lithographic techniques with additive tissue engineering methods. We created a network platform consisting of interconnected microchannels to model a highly vascularized system and successfully perfused the system with fluorescent particles. Finally, we developed a physiologically representative in vitro microfluidic platform with vasculature patterned from in vivo data showing the versatility of these systems to replicate the complex geometries of tumor microvasculature and dynamically measured particle transport. Overall, we have shown the ability to develop functional microfluidic vascular tumor platforms of varying complexities and demonstrated their utility for studying spatial particle transport within these systems.
Segmental bone replacement via patient‐specific, three‐dimensional printed bioresorbable graft substitutes and their use as templates for the culture of mesenchymal stem cells under mechanical stimulation at various frequencies
Authors: Chung Rebecca , Kalyon Dilhan M. , Yu Xiaojun , Valdevit Antonio
Published: June 2018

The treatment of large segmental bone defects remains a challenge as infection, delayed union, and nonunion are common postoperative complications. A three‐dimensional printed bioresorbable and physiologically load‐sustaining graft substitute was developed to mimic native bone tissue for segmental bone repair. Fabricated from polylactic acid, this graft substitute is novel as it is readily customizable to accommodate the particular size and location of the segmental bone of the patient to be replaced. Inspired by the structure of the native bone tissue, the graft substitute exhibits a gradient in porosity and pore size in the radial direction and exhibit mechanical properties similar to those of the native bone tissue. The graft substitute can serve as a template for tissue constructs via seeding with stem cells. The biocompatibility of such templates was tested under in vitro conditions using a dynamic culture of human mesenchymal stem cells. The effects of the mechanical loading of cell‐seeded templates under in vitro conditions were assessed via subjecting the tissue constructs to 28 days of daily mechanical stimulation. The frequency of loading was found to have a significant effect on the rate of mineralization, as the alkaline phosphatase activity and calcium deposition were determined to be particularly high at the typical walking frequency of 2 Hz, suggesting that mechanical stimulation plays a significant role in facilitating the healing process of bone defects. Utilization of such patient‐specific and biocompatible graft substitutes, coupled with patient’s bone marrow cells seeded and exposed to mechanical stimulation of 2 Hz have the potential of reducing significant volumes of cadaveric tissue required, improving long‐term graft stability and incorporation, and alleviating financial burdens associated with delayed or failed fusions of long bone defects.
Covalent Chemical Cochaperones of the p300/CBP GACKIX Domain
Authors: Lodge Jean M. , Majmudar Chinmay Y. , Clayton James , Mapp Anna K.
Published: June 2018

The GACKIX activator binding domain has been a compelling target for small‐molecule probe discovery because of the central role of activator–GACKIX complexes in diseases ranging from leukemia to memory disorders. Additionally, GACKIX is an ideal model to dissect the context‐dependent function of activator–coactivator complexes. However, the dynamic and transient protein–protein interactions (PPIs) formed by GACKIX are difficult targets for small molecules. An additional complication is that activator‐binding motifs, such as GACKIX, are found in multiple coactivators, making specificity difficult to attain. In this study, we demonstrate that the strategy of tethering can be used to rapidly discover highly specific covalent modulators of the dynamic PPIs between activators and coactivators. These serve as both ortho‐ and allosteric modulators, enabling the tunable assembly or disassembly of the activator–coactivator complexes formed between the KIX domain and its cognate activator binding partners MLL and CREB. The molecules maintain their function and selectivity, even in human cell lysates and in bacterial cells, and thus, will ultimately be highly useful probes for cellular studies.
Sodium Aminotroponiminates: Ligand‐Induced Disproportionation, Mixed‐Metal Compounds, and Exceptional Activity in Polymerization Catalysis
Authors: Hanft Anna , Jürgensen Malte , Bertermann Rüdiger , Lichtenberg Crispin
Published: June 2018

Sodium complexes of aminotroponiminate (ATI) ligands have been reacted with a range of neutral donor ligands. Upon addition of crown ethers, they undergo an unusual ligand‐induced disproportionation reaction with formation of [Na(ATI)2]− sodiate complex anions. The same structural motif has also been found in the first well‐defined mixed‐metal ATI complexes, which have been accessed starting from monometallic sodium and potassium species. The mixed‐metal compounds confirm the possibility of ATIs to act as ditopic ligands. Using the polymerization of ϵ‐caprolactone as a model system, structure‐reactivity‐relationships in sodium and mixed‐metal ATI compounds have been studied by comparing the reactivity of [Na(ATI)] and [Na(ATI)2]− structural motifs. These studies revealed trends in the catalyst activity depending on the nuclearity of the complex and the substitution pattern at the ATI ligand. Exceptionally high activities were obtained for dinuclear sodium sodiates of type [Na(crown)2][Na(ATI)2], making them the most active alkali metal initiators for this reaction. The organometallic and polymeric compounds presented in this work have been characterized by techniques including (VT‐)NMR spectroscopy, single‐crystal X‐ray diffraction, gel permeation chromatography, mass spectrometry, and DFT calculations.
Effects of Temperature on the Filtration Characteristics of a Dual‐Layer Granular Bed Filter
Authors: Shen Wei-Jie , Yang Guo-Hua , Liu Peng , Yao Zhi-Wei , Shi Hua-Jie , Cui Yu-Yong , Li Zhen
Published: June 2018

The effects of temperature on the filtration efficiency and pressure drop of a dual‐layer granular bed filter were investigated in a hot dual‐layer granular bed filter with experimental dust. Enhanced higher filtration efficiency was obtained with higher filtration temperature, and the removal efficiency of ultrafine dust was also at a high level. Simultaneously, the total pressure drop maintained at an acceptable range. The results demonstrate that the dual‐layer granular bed has excellent prospects for application to low‐temperature coal pyrolysis.
Overcoming the Inertness of Iridium(III) in a Facile Single‐Crystal to Single‐Crystal Reaction of Iodine Vapor with a Cyclometalated Chloride Monomer
Authors: Bezzubov Stanislav I. , Kalle Paulina , Bilyalova Alfiya A. , Tatarin Sergei V. , Dolzhenko Vladimir D.
Published: June 2018

Iridium(III) is often considered to be one of the most inert octahedral metal ions. Herein we present a phenanthroimidazole‐based bis‐cyclometalated iridium(III) chloride undergoing a facile chloro ligand exchange with iodine, in a gas‐solid reaction under ambient conditions. Monitoring the progress of the reaction by X‐ray diffraction analysis reveals the crystal‐packing‐induced exceptional stereoselectivity of this topochemical transformation. The results provide excellent opportunities to modulate the geometry and kinetic properties of cyclometalated iridium(III) complexes that may be very promising in catalysis and design of anticancer agents.
A Novel Sc(OTf)3‐Catalyzed (2+2+1)‐Cycloannulation/Aza‐Friedel–Crafts Alkylation Sequence toward Multicyclic 2‐Pyrrolines
Authors: Schlegel Marcel , Coburger Peter , Schneider Christoph
Published: June 2018

The rapid assembly of molecular complexity continues to be at the forefront of novel reaction development. In the pursuit of that goal, we herein report a novel Sc(OTf)3‐catalyzed, one‐pot multicomponent reaction that furnishes complex multicyclic 2‐pyrrolines with excellent overall yields and perfect diastereocontrol. This process is based on our previously established (2+2+1)‐cycloannulation of in situ generated 1‐azaallyl cations, 1,3‐dicarbonyls and primary amines. The newly formed and highly reactive aminal moiety is readily substituted with indoles and pyrroles both as external and internal π‐nucleophiles to provide densely functionalized N‐heterocycles with four new σ‐bonds and two vicinal quaternary stereogenic centers. In addition, DFT calculations have been conducted to further characterize the intermediate 1‐azaallyl cations.
Luminescence from Lanthanide(III) Ions Bound to the Glycocalyx of Chinese Hamster Ovary Cells
Authors: Arppe‐Tabbara Riikka , Carro‐Temboury Miguel R. , Hempel Casper , Vosch Tom , Sørensen Thomas Just
Published: June 2018

Lanthanide(III) ions bind to the glycocalyx of Chinese Hamster Ovary (CHO) cells and give rise to a unique luminescent fingerprint. Following direct excitation of terbium(III) and europium(III) ions in the visible part of the spectrum, we are able to collect emission spectra pixel‐by‐pixel in images of CHO cells. Following data analysis that removes the background signal, the fine structure of the europium(III) luminescence indicate that the lanthanide(III) ions are bound to a single structure of the CHO cell glycocalyx. This was deduced from the fact that the structure‐sensitive emission spectrum of europium is unchanged throughout the investigated samples.
Realizing the Potential of Acetylenedicarboxylate by Functionalization to Halofumarate in ZrIV Metal–Organic Frameworks
Authors: Ma Ntep Tobie J. Matemb , Reinsch Helge , Moll Bastian , Hastürk Emrah , Gökpinar Serkan , Breitzke Hergen , Schlüsener Carsten , Schmolke Laura , Buntkowsky Gerd , Janiak Christoph
Published: June 2018

A strategy was developed to obtain from acetylenedicarboxylic acid either an acetylenedicarboxylate‐based ZrIV metal–organic framework (MOF) with fcu topology or a halo‐functionalized‐MOF‐801 through in situ ligand hydrohalogenation. The new materials feature exceptionally high hydrophilicity and CO2/H2 adsorption energetics. The acetylenedicarboxylate linker and its functionalizable triple‐bond discloses its potential in the engineering of microporous materials with targeted properties.
Designing Deep‐UV Birefringent Crystals by Cation Regulation
Authors: Zhang Zhizhong , Wang Ying , Zhang Bingbing , Yang Zhihua , Pan Shilie
Published: June 2018

Two new alkaline earth metal fluorooxoborates, CaB4O6F2 and SrB4O6F2, have been synthesized and characterized. The title compounds are isostructural and crystallize in centrosymmetric space group P
(No. 2). Structurally, the fundamental building blocks, B4O8F2 groups, are connected by B−O bonds to form [B4O6F2]∞ layers, which stack parallelly along the c axis. In addition, BaB4O6F2, a known fluorooxoborate with different crystal structure, was also synthesized and characterized for comparison. The cation size influence on the structure of this MB4O6F2 (M=Ca, Sr, Ba) family is discussed in detail. The diffuse‐reflectance spectroscopy measurements indicate that the cutoff edges of title compounds are below 190 nm. Moreover, first‐principle calculation results demonstrate that MB4O6F2 (M=Ca, Sr, Ba) have large birefringence of 0.091, 0.089, and 0.085 at 1064 nm. Both experimental and theoretical studies suggest that MB4O6F2 (M=Ca, Sr, Ba) are promising birefringent materials for deep‐UV applications.
Are Sc—C and Sc—P Bonds Reactive in Scandium Phosphinoalkylidene Complex? Insights on a Versatile Reactivity
Authors: Mao Weiqing , Xiang Li , Lamsfus Carlos Alvarez , Maron Laurent , Leng Xuebing , Chen Yaofeng
Published: June 2018

The peculiar electronic structure of scandium phosphinoalkylidene complex [LSc{C(SiMe3)PPh2}THF] (L=[MeC(NDIPP)CHC(NDIPP)Me]−), DIPP=2,6‐(iPr)2C6H3) leads to an interesting versatile reactivity, which is demonstrated both experimentally and computationally. The complex undergoes [2+2] cycloaddition reactions with alkynes, and easily activates various X—O bonds such as C—O of propylene oxide, N—O of 3,5‐dimethylisoxazole, B—O of pinacolborane and Si—O of triethoxysilane. These reactions occur on the Sc—C bond of the phosphinoalkylidene complex. Interestingly, the Sc—P bond can also be activated as the presence of a Sc—C—P three center π interaction in the complex allows performing C—F activation of 2,6‐difluoropyridine and 1,2 addition with imine or ketone. The complex also reacts with metal complexes, [(COD)RhCl]2 and (Ph3P)AuCl, to form structural intriguing heterobimetallic complexes.
The basal interstitial nucleus (BIN) of the cerebellum provides diffuse ascending inhibitory input to the floccular granule cell layer
Authors: Jaarsma Dick , Blot Francois G. C. , Wu Bin , Venkatesan Subramanian , Voogd Jan , Meijer Dies , Ruigrok Tom J. H. , Gao Zhenyu , Schonewille Martijn , De Zeeuw Chris I.
Published: June 2018

The basal interstitial nucleus (BIN) in the white matter of the vestibulocerebellum has been defined more than three decades ago, but has since been largely ignored. It is still unclear which neurotransmitters are being used by BIN neurons, how these neurons are connected to the rest of the brain and what their activity patterns look like. Here, we studied BIN neurons in a range of mammals, including macaque, human, rat, mouse, rabbit, and ferret, using tracing, immunohistological and electrophysiological approaches. We show that BIN neurons are GABAergic and glycinergic, that in primates they also express the marker for cholinergic neurons choline acetyl transferase (ChAT), that they project with beaded fibers to the glomeruli in the granular layer of the ipsilateral floccular complex, and that they are driven by excitation from the ipsilateral and contralateral medio‐dorsal medullary gigantocellular reticular formation. Systematic analysis of codistribution of the inhibitory synapse marker VIAAT, BIN axons, and Golgi cell marker mGluR2 indicate that BIN axon terminals complement Golgi cell axon terminals in glomeruli, accounting for a considerable proportion ( > 20%) of the inhibitory terminals in the granule cell layer of the floccular complex. Together, these data show that BIN neurons represent a novel and relevant inhibitory input to the part of the vestibulocerebellum that controls compensatory and smooth pursuit eye movements.
High‐Quality Yeast‐2‐Hybrid Interaction Network Mapping
Authors: Altmann Melina , Altmann Stefan , Falter Claudia , Falter‐Braun Pascal
Published: June 2018

In this article, we describe a Y2H interaction mapping protocol for systematically screening medium‐to‐large collections of open reading frames (ORFs) against each other. The protocol is well suited for analysis of focused networks, for modules of interest, assembling genome‐scale interactome maps, and investigating host‐microbe interactions. The four‐step high‐throughput protocol has a demonstrated low false‐discovery rate that is essential for producing meaningful network maps. Following the assembly of yeast expression clones from an existing ORFeome collection, we describe in detail the four‐step procedure that begins with the primary screen using minipools, followed by secondary verification of primary positives, identification of candidate interaction pairs by sequencing, and a final verification step using fresh inoculants. In addition to this core protocol, aspects of network mapping and quality control will be discussed briefly. © 2018 by John Wiley & Sons, Inc.
Growth, condition, and maturity schedules of an estuarine fish species change in estuaries following increased hypoxia due to climate change
Authors: Cottingham Alan , Huang Peisheng , Hipsey Matthew R. , Hall Norman G. , Ashworth Eloise , Williams Joel , Potter Ian C.
Published: June 2018

Understanding challenges posed by climate change to estuaries and their faunas remains a high priority for managing these systems and their communities. Freshwater discharge into a range of estuary types in south‐western Australia between 1990 and 2015 is shown to be related to rainfall. This largely accounts for decreases in discharge in this microtidal region being more pronounced on the west coast than south coast, where rainfall decline was less. Results of an oxygen‐balance model imply that, as demonstrated by empirical data for the Swan River Estuary, declines in discharge into a range of estuary types would be accompanied by increases in the extent of hypoxia. In 2013–15, growth and body condition of the teleost Acanthopagrus butcheri varied markedly among three permanently open, one intermittently‐open, one seasonally‐closed and one normally‐closed estuary, with average time taken by females to reach the minimum legal length (MLL) of 250 mm ranging from 3.6 to 17.7 years. It is proposed that, in a given restricted period, these inter‐estuary variations in biological characteristics are related more to differences in factors, such as food resources and density, than to temperature and salinity. The biological characteristics of A. butcheri in the four estuaries, for which there are historical data, changed markedly between 1993–96 and 2013–15. Growth of both sexes, and also body condition in all but the normally‐closed estuary, declined, with females taking between 1.7 and 2.9 times longer to attain the MLL. Irrespective of period, body condition, and growth are positively related. Age at maturity typically increased between periods, but length at maturity declined only in the estuary in which growth was greatest. The plasticity of the biological characteristics of A. butcheri, allied with confinement to its natal estuary and ability to tolerate a wide range of environmental conditions, makes this sparid and comparable species excellent subjects for assessing estuarine “health.”
Rethinking the importance of the structure of ecological networks under an environment‐dependent framework
Authors: Cenci Simone , Song Chuliang , Saavedra Serguei
Published: June 2018

A major quest in network and community ecology has been centered on understanding the importance of structural patterns in species interaction networks—the synthesis of who interacts with whom in a given location and time. In the past decades, much effort has been devoted to infer the importance of a particular structure by its capacity to tolerate an external perturbation on its structure or dynamics. Here, we demonstrate that such a perspective leads to inconsistent conclusions. That is, the importance of a network structure changes as a function of the external perturbations acting on a community at any given point in time. Thus, we discuss a research agenda to investigate the relative importance of the structure of ecological networks under an environment‐dependent framework. We hypothesize that only by studying systematically the link between network structure and community dynamics under an environment‐dependent framework, we can uncover the limits at which communities can tolerate environmental changes.
Patterns of maximum height of endemic woody seed plants in relation to environmental factors in China
Authors: Yu Ruoyun , Liu Hua , Huang Jihong , Lu Xinghui , Zang Runguo , Ma Keping , Guo Zhongjun , Ding Yi , Li Huan , Liu Yibo , Li Qian
Published: June 2018

The maximum height of plants is an important trait determining community structure and ecosystem function. However, the variation in maximum plant height along large‐scale environmental gradients is still largely unknown. Here, data of maximum height for 2796 endemic woody seed plant species and 23 environmental variables (climate, space, and soil) were collected in China. Distribution patterns of maximum plant height were detected, and the relative importance of different environmental variables to maximum plant height was also determined. The maximum height of 2439 Chinese endemic woody seed plant species was lower than 16 m. The number of endemic woody seed plant species decreased gradually with increasing maximum plant height. At the county level, the mean maximum plant height (MMPH) of endemic woody seed plant species had an increasing trend from northwest to southeast across China. The environmental factors explained 19% of the variance in MMPH, among which climate explained more variation in MMPH than did space and soil. The most important predictors of MMPH were mean temperature of the warmest quarter, annual mean temperature, temperature seasonality, and altitude. These results demonstrate that the maximum height of endemic woody seed plants across China strongly responds to temperature. Our findings provide the first study elucidating the patterns in maximum height of Chinese endemic woody seed plants and identifying the most influential environmental factors for the variation in this trait, which will contribute to the development of sounder theory on the macropatterns of plant distribution.
Rapid Access to 3‐Acyl‐5‐alkoxybutyrolactams Using Triplet and Singlet Oxygen
Authors: Sofiadis Manolis , Sarris John , Montagnon Tamsyn , Kalaitzakis Dimitris , Vassilikogiannakis Georgios
Published: June 2018

A straightforward singlet oxygen‐initiated cascade reaction sequence for the synthesis of a variety of key 3‐acyl‐5‐alkoxybutyrolactams from furans has been developed.
Nitrogen‐Bridged, Natural Product Like Octahydrobenzofurans and Octahydroindoles: Scope and Mechanism of Bridge‐Forming Reductive Amination via Caged Heteroadamantanes
Authors: Wales Steven. M. , Adcock Holly V. , Lewis William , Hamza Daniel , Moody Christopher J.
Published: June 2018

The biological significance of sp3‐rich synthetic scaffolds with natural product like features yet distinct global frameworks is being increasingly recognized in medicinal chemistry and biochemistry. Taking inspiration from the vast array of bioactive, bridged alkaloids, we report the synthesis of unique, densely functionalized tricyclic scaffolds based on nitrogen‐bridged octahydrobenzofurans and octahydroindoles. These heterocycle‐rich frameworks were assembled by a one‐pot, two‐step bridge‐forming reductive amination process, which was shown to proceed via caged, heteroadamantane intermediates that thermodynamically drive an exo–endo epimerization, enabling intramolecular aza‐Michael addition over the concave face of the fused bicyclic precursors. In addition to evaluating the scope of this aza‐bridge‐forming reaction, further stereochemical complexity was introduced by subsequent diastereoselective ketone reductions and other manipulations. Finally, strategic diversity points (amino, carboxy) were decorated with common medicinal chemistry fragments, providing a set of exemplar derivatives with Lipinski‐compliant physicochemical properties.
The use of response surface methodology to determine governing factors driving a nanodiamond‐based wastewater treatment method
Authors: Butler Erick , Mulamba Oliver , Webb Summer , Pimentel Andy
Published: June 2018

The purpose of this study was to determine and characterize the factors involved in the treatment of wastewater containing an azo dye, Congo red, using nanodiamond (ND). A Box Behnken study was developed by the authors that considered the dye wastewater dilution, catalyst dose, and light source. Statistical analysis, XRD, and SEM analysis confirmed that ND loses its effectiveness when the concentration is below 0.025 g/100 mL of Congo red. It was also determined that at these catalyst doses ND is primarily driven by adsorption, confirmed by observing high treatment efficiency within 30 min of each experimental run. While one cannot absolutely confirm this is the case at much higher doses of ND, it was clear that adsorption plays a major role in color removal by the carbon allotrope. An additional EDS analysis shows that ND specifically adsorbs of sodium, lead, chlorine, and sulfur from Congo red. © 2018 American Institute of Chemical Engineers Environ Prog, 38: 246–253, 2019
Health and broader community benefit of parkrun—An exploratory qualitative study
Authors: Sharman Melanie J. , Nash Meredith , Cleland Verity
Published: June 2018

Issue addressed

parkrun is a free, weekly, timed, international mass community 5‐km walk/run event. Unlike other paid events, parkrun attracts populations harder to engage in physical activity (PA) (eg, women, those with overweight/obesity or illness/injury/disability). This exploratory qualitative study investigated the individual, social and environmental factors associated with parkrun's broad appeal in Australia.

Methods

Tasmanian parkrunners who completed a quantitative survey (2016) were purposively recruited for a 2017 interview study. Semistructured interviews focused on reasons for parkrun participation. Data saturation was achieved by the tenth interview. Data were analysed thematically.

Results

Four themes emerged: (a) participation facilitators and barriers; (b) PA gain and broader community benefit; (c) social connections/networks; and (d) organisational issues. Appealing characteristics of parkrun included strong social support, performance gain opportunities, socialising, inclusivity (eg, all ages/abilities), sense of community, positive atmosphere and accessibility (eg, no cost and convenience). Some participants reported that parkrun had stimulated gains in their total PA (not always limited to walking/running) and that parkrun may also result in other community benefits (eg, supporting local businesses, fee‐based running club/event participation and “parkrun tourism”). Most participants first attended parkrun because of encouragement from their social networks, and participants subsequently encouraged others to attend. Participants found parkrun events well organised, but identified some potential threats (eg, local politics).

Conclusions

Social factors appeared critical in driving initial and ongoing parkrun participation. parkrun may lead to wider community benefits beyond that gained through increased individual PA. These findings highlight the “success factors” driving parkrun participation and provide insights for other community‐based PA promotion activities.
Hydrological dynamics of prairie pothole wetlands: Dominant processes and landscape controls under contrasted conditions
Authors: Haque Aminul , Ali Genevieve , Badiou Pascal
Published: June 2018

Numerous studies have examined the impact of prairie pothole wetlands on overall watershed dynamics. However, very few have looked at individual wetland dynamics across a continuum of alteration status using subdaily hydrometric data. Here, the importance of surface and subsurface water storage dynamics in the prairie pothole region was documented by (1) characterizing surface fill–spill dynamics in intact and consolidated wetlands; (2) quantifying water‐table fluctuations and the occurrence of overland flow downslope of fully drained wetlands; (3) assessing the relation (or lack thereof) between intact, consolidated or drained wetland hydrological behaviour, and stream dynamics; and (4) relating wetland hydrological behaviour to landscape characteristics. Focus was on southwestern Manitoba, Canada, where ten intact, three consolidated, seven fully drained wetlands, and a nearby creek were monitored over two years with differing antecedent storage conditions. Hourly hydrological time series were used to compute behavioural metrics reflective of year‐specific and season‐specific wetland dynamics. Behavioural metrics were then correlated to wetland physical characteristics to identify landscape controls on wetland hydrology. Predictably, more frequent spillage or overland flow was observed when antecedent storage was high. Consolidated wetlands had a high degree of water permanence and a greater frequency of fill–spill events than intact wetlands. Shallow and highly responsive water tables were present downslope of fully drained wetlands. Potential wetland–stream connectivity was also inferred via time‐series analysis, while some landscape characteristics (e.g., wetland surface, catchment area, and storage volume) strongly correlated with wetland behavioural metrics. The nonstationarity of dominant processes was, however, evident through the lack of consistent correlations across seasons. This, therefore, highlights the importance of combining multiyear high‐frequency hydrometric data and detailed landscape analyses in wetland hydrology studies.