bluuebunny/crossref_metadata_2025 huggingface dataset:
Agenciamientos en las sociedades de control
Authors: Rossi Luis Sebastián Ramón
Published: June 2020

El objetivo de este artículo es presentar las principales tesis detrás de la teoría de Gilles Deleuze y Félix Guattari sobre la aparición de las formaciones sociales de control y sobre los agenciamientos que a ellas corresponden. Así, se recorrerán tres tesis fundamentales sobre la mutación del capitalismo contemporáneo. En el primer apartado se abordarán las transformaciones en las relaciones de poder y en las formaciones de saber. En el segundo, nos detendremos en los cambios en los modos de subjetivación (de la sujeción social a la esclavitud maquínica). Por último, exploraremos los nuevos regímenes de imágenes y de signos que nuestros autores hicieron corresponder con las sociedades contemporáneas. No obstante, ninguna de estas transformaciones es legible, para la teoría social crítica deleuzoguattariana, sin los agenciamientos concretos en los que tienen lugar. Por ello abordaremos algunos ejemplos de componendas de la computación ubicua que ilustrarán las dimensiones de las nuevas vías de modulación (codificación) del poder contemporáneo y de agenciamientos massmediáticos que aseguran formas novedosas de reterritorializaciones por medios artificiales (territorialización). Hacia el final nos detendremos en el dato primario de toda formación social, sus posibles líneas de fuga.
Monitoring Body Weight Gain of Goat Kids for Improving Productivity
Authors: Hegde Narayan G. , Deo Avinash D.
Published: June 2020

Goat husbandry has been supporting the livelihood of over 100 million families living in arid and semi-arid regions of Asia and Africa, but most of them have not been able to earn substantial income, due to poor goat husbandry practices. Key factors influencing goat productivity have been - better management of pregnant does, high weight of kids at birth and acceleration of weight gain during pre-weaning period, apart from general factors such as goat breed, efficient breeding service, health care and marketing. This paper has identified various factors contributing to poor status of goats owned by small goat keepers and suggestions to improve the weight of kids at birth and the growth rate during pre-weaning and post weaning periods, through supplementary feeding and regular monitoring of weight. A suitable extension tool in the form of a Growth Monitoring Chart for different breeds can be developed, which goat keepers can readily use for taking suitable corrective measures. Goat keepers should also be advised on culling weak animals at an early age and replacing them with healthy animals to improve the production.
Study of Cattle Trampling and Its Effect on Soil Properties and Sorghum Productivity in Parts of Yobe State, Nigeria
Authors: Ali A. , Usman M. , Nangere M. G.
Published: June 2020

This study was carried out at three different locations in Yobe State (North Eastern Nigeria), to determine the effect of cattle trampling on soil properties and sorghum productivity. The study locations were Potiskum, Nangere and Fika Local Government Areas of the state. Soil depth (25-30 cm height and diameter) were collected from each location and analyzed for particle size distribution, pH, organic carbon (OC), total nitrogen (TN), available phosphorus and exchangeable cations as well as cation exchange capacity (CEC), bulk density (BD), total porosity (Pt) and saturated hydraulic conductivity (Ksat). Each sampling involved collection from cattle trampled and un-trampled areas with sorghum as the test crop. Effect of trampling on root mass, length and stover yields were also determined after sorghum cultivation in each of the location. Results indicated that there were significant effects of cattle trampling with respect to soil properties investigated. However, post planting results of the analysis revealed that trampled soils had significantly lower statistical values for all yield parameters of sorghum when compared with un-trampled soils in all the study locations. There is need to improve the structure of soils in all study locations through incorporation of organic matter and proper soil management for increased permeability, root penetration, aeration and water infiltration. Also, there is need for cattle routes demarcations to provide free movement of livestock across the locations without encroachment into farmlands.
Residual Toxicity of Newer Insecticide Molecules against Shoot and Fruit Borer of Okra
Authors: Pandey Sagar Anand , Sahu Saswati , Koshta V. K. , Devi Monika , Mishra Pradeep
Published: June 2020

Seven new molecule insecticides viz., Deltamethrin, Lambda-cyhalothrin, Emamectin benzoate, Indoxacarb, Bifenthrin, Rynaxypr and Flubendiamide were bio-assayed against okra shoot and fruit borer (Earias vittella) to study the residual toxicity on Okra at College of Agriculture, Raipur during the Rabi applied season(2014-15 and 2015-16).. On the basis of average LT50 values, the order of toxicity was Emamectin Benzoate > Indoxacarb > Lambda-Cyhalothrin > Rynaxypr > Flubendiamide > Deltamethrin > Bifenthrin against okra shoot and fruit borer.
Time Series Modelling of The Volume of Overland Timber Export in The Bolgatanga Municipality
Authors: Kpamma Henry M. , Bruku Silverius K. , Awaab John A.
Published: June 2020

Aims/ Objectives: This research was carried out with the intention of using time series to model the volume of overland timber exported within Bolgatanga municipalityPlace and Duration of Study: Study of the time series was based on a historical data of the volume of timber exported for twenty consecutive years, from 1999 to 2019 within Bolgatanga municipality.Methodology: The three-stage iterative modeling approach for Box Jenkins was used to match an ARIMA model and to forecast both the amount of timber export and the confiscated lumber. ARIMA method incorporates a cycle of autoregressive and a moving average. The three-stage iterative modeling technique of Box Jenkins which were used are model recognition, parameter estimation and/or diagnostic checks were also made.

Results: From the preliminary investigation, the study showed that the amount of timber exported in municipality is skewed to the right, suggesting that much of the amount of timber exported is below the average. This, together with the high volatility in the volume of timber exported, indicates that the amount of timber exported within the municipalities during the twenty-year period was low. The plots from the trends also showed robust variations in the volume of timber exported indicating that timber exporters do not have better grips with the concepts and applications of export technology, hence the erratic nature of the volume of timber exported over the period. The quadratic pattern and the ARIMA (1,1,1) model best represented the amount of timber exported.The analysis further indicated that there will be a further decrease in the amount of timber export from the five years projection into the future. Over the last two decades the Bayesian approach to VAR has gained ground. For a future report, this estimation method will be followed to examine the ”long-run equilibrium relationships” between timber export volumes and climate change.Conclusion: The quadratic pattern and the ARIMA (1,1,1) model best represented the amount of timber exported. There will be a further decrease in the amount of timber export from the five years projection into the future.
Delayed Nutrient Conversion for a Single Species Periodic Chemostat
Authors: Ireri Jane , Pokhariyal Ganesh , Moindi Stephene
Published: June 2020

In this paper we analyze a Chemostat model with periodic nutrient input modelled using Fourier series and incorporate delays in nutrient conversion. We show that both periodicity and delays have complementing influence in the long term behaviour of the species. Numerical results show that periodicity has bigger influence on species density variations for delays below the Hopf Bifurcation point, while for delays above the Bifurcation point,the delay effect is more influential.
The helically‐acquired CTDIvol as an alternative to traditional methodology
Authors: Leon Stephanie M. , Kobistek Robert J. , Olguin Edmond A. , Zhang Zhongwei , Barreto Izabella L. , Schwarz Bryan C.
Published: June 2020

Purpose

Most clinical computed tomography (CT) protocols use helical scanning; however, the traditional method for CTDIvol measurement replaces the helical protocol with an axial scan, which is not easily accomplished on many scanners and may lead to unmatched collimation settings and bowtie filters. This study assesses whether CTDIvol can be accurately measured with a helical scan and determines the impact of pitch, collimation width, and excess scan length.

Methods

CTDIvol was measured for 95 helical protocols on 31 CT scanners from all major manufacturers. CTDIvol was measured axially, then again helically, with the scan range set to the active area of the pencil chamber seen on the localizer image. CTDIvol measurements using each method were compared to each other and to the scanner‐displayed CTDIvol. To test the impact of scan length, the study was repeated on four scanners, with the scan range set to the phantom borders seen on the localizer.

Results

It was not possible to match the collimation width between the axial and helical modes for 12 of the 95 protocols tested. For helical and axial protocols with matched collimation, the difference between the two methods averaged below 1 mGy with a correlation of R2 = 0.99. The difference between the methods was not statistically significant (P = 0.81). The traditional method produced four measurements that differed from the displayed CTDIvol by >20%; no helical measurements did. The accuracy of the helical CTDIvol was independent of protocol pitch (R2 = 0.0) or collimation (R2 = 0.0). Extending the scan range to the phantom borders increased the measured CTDIvol by 2.1%–9.7%.

Conclusion

There was excellent agreement between the two measurement methods and to the displayed CTDIvol, without protocol or vendor dependence. The helical CTDIvol measurement can be accomplished more easily than the axial method on many scanners and is reasonable to use for QC purposes.
Younger adults report more distress and less well‐being: A cross‐cultural study of event centrality, depression, post‐traumatic stress disorder and life satisfaction
Authors: Zaragoza Scherman Alejandra , Salgado Sinué , Shao Zhifang , Berntsen Dorthe
Published: June 2020

The extent to which highly emotional autobiographical memories become central to one's identity and life story influences mental health. Young adults report higher distress and lower well‐being, compared with middle‐aged and/or older adults; whether this replicates across cultures is still unclear. First, we provide a review of the literature that examines age‐differences in depression, post‐traumatic stress disorder (PTSD), and life satisfaction in adulthood across cultures. Second, we report findings from a cross‐cultural study that examined event centrality of highly positive and negative autobiographical memories along with symptoms of depression and PTSD, and levels of life satisfaction in approximately 1000 young and middle‐aged adults from Mexico, Greenland, China and Denmark. Both age groups provided higher centrality ratings to the positive life event; however, the relative difference between the ratings for the positive and negative event was smaller in the young adults. Young adults reported significantly more distress and less well‐being across cultures.
Electromechanical Properties of Robocasted Barium Titanate Ceramics
Authors: Lorenz Mylena , Martin Alexander , Webber Kyle G. , Travitzky Nahum
Published: June 2020

This work presents the fabrication of dense polycrystalline barium titanate (BaTiO3, BT) for electromechanical transduction using robocasting and cold isostatic pressing (CIP). The use of CIP as post‐treatment is proposed to eliminate defects and increase the density of robocasted parts to improve the piezoelectric performance. For robocasting, pastes containing 50 and 52 vol% are developed; the resulting green robocasted parts are CIPed at 100 and 150 MPa. Using this proposed technique, samples robocasted with BT52 and CIPed at 150 MPa display a relative density of ≈98%, comparable with reference polycrystalline samples. In addition, an increase in both the piezoelectric charge and voltage coefficient is observed in robocasted parts, with the values up to 195 pC/N and 12 × 10−3 Vm N−1, respectively. These values, which are comparable with previous studies of polycrystalline BT, indicate that the combined robocasting and CIP technique is a possible method for producing 3D printed piezoelectric sensors.
New Polymorphs of 2D Indium Selenide with Enhanced Electronic Properties
Authors: Sun Yuanhui , Li Yawen , Li Tianshu , Biswas Koushik , Patanè Amalia , Zhang Lijun
Published: June 2020

The 2D semiconductor indium selenide (InSe) has attracted significant interest due its unique electronic band structure, high electron mobility, and wide tunability of its band gap energy achieved by varying the layer thickness. All these features make 2D InSe a potential candidate for advanced electronic and optoelectronic applications. Here, the discovery of new polymorphs of InSe with enhanced electronic properties is reported. Using a global structure search that combines artificial swarm intelligence with first‐principles energetic calculations, polymorphs that consist of a centrosymmetric monolayer belonging to the point group D3d are identified, distinct from well‐known polymorphs based on the D3h monolayers that lack inversion symmetry. The new polymorphs are thermodynamically and kinetically stable, and exhibit a wider optical spectral response and larger electron mobilities compared to the known polymorphs. Opportunities to synthesize these newly discovered polymorphs and viable routes to identify them by X‐ray diffraction, Raman spectroscopy, and second harmonic generation experiments are discussed.
Multicompartment Polymer Vesicles with Artificial Organelles for Signal‐Triggered Cascade Reactions Including Cytoskeleton Formation
Authors: Belluati Andrea , Thamboo Sagana , Najer Adrian , Maffeis Viviana , von Planta Claudio , Craciun Ioana , Palivan Cornelia G. , Meier Wolfgang
Published: June 2020

Organelles, i.e., internal subcompartments of cells, are fundamental to spatially separate cellular processes, while controlled intercompartment communication is essential for signal transduction. Furthermore, dynamic remodeling of the cytoskeleton provides the mechanical basis for cell shape transformations and mobility. In a quest to develop cell‐like smart synthetic materials, exhibiting functional flexibility, a self‐assembled vesicular multicompartment system, comprised of a polymeric membrane (giant unilamellar vesicle, GUV) enveloping polymeric artificial organelles (vesicles, nanoparticles), is herein presented. Such multicompartment assemblies respond to an external stimulus that is transduced through a precise sequence. Stimuli‐triggered communication between two types of internal artificial organelles induces and localizes an enzymatic reaction and allows ion‐channel mediated release from storage vacuoles. Moreover, cytoskeleton formation in the GUVs' lumen can be triggered by addition of ionophores and ions. An additional level of control is achieved by signal‐triggered ionophore translocation from organelles to the outer membrane, triggering cytoskeleton formation. This system is further used to study the diffusion of various cytoskeletal drugs across the synthetic outer membrane, demonstrating potential applicability, e.g., anticancer drug screening. Such multicompartment assemblies represent a robust system harboring many different functionalities and are a considerable leap in the application of cell logics to reactive and smart synthetic materials.
Ru Species Supported on MOF‐Derived N‐Doped TiO2/C Hybrids as Efficient Electrocatalytic/Photocatalytic Hydrogen Evolution Reaction Catalysts
Authors: Yan Baolin , Liu Dapeng , Feng Xilan , Shao Mingzhe , Zhang Yu
Published: June 2020

The development of efficient catalysts is of great importance for hydrogen evolution reaction (HER) of water splitting via electrocatalytic/photocatalytic processes to remediate the current severe environmental and energy problems. By aid of the stabilization effects of uncoordinated groups and inherent pore‐confinement of amine‐functionalized metal–organic frameworks (NH2‐MIL‐125), two forms of Ru species including nanoparticles (NPs) and/or single atoms (SAs) can be firmly embedded in NH2‐MIL‐125 derived N‐doped TiO2/C support (N‐TC), and thus obtain two kinds of samples named Ru‐NPs/SAs@N‐TC and Ru‐SAs@N‐TC, respectively. In the synthetic process, the initial feeding amount of Ru3+ ions not only strongly determines the final size and dispersion states of Ru species but also the morphology and defective structures of N‐TC support. Impressively, Ru‐NPs/SAs@N‐TC exhibit superior catalytic activities to Ru‐SAs@N‐TC for either electrocatalytic or photocatalytic HER. This should be attributed to its larger specific surface area and benefiting from synergistic coupling of Ru NPs and Ru SAs. It is envisioned that the present work can provide a new avenue for development of high‐efficiency and multifunctional hybrid catalysts in sustainable energy conversion.
High‐Performance On‐Chip Electron Sources Based on Electroformed Silicon Oxide
Authors: Yang Wei , Li Zhiwei , Wang Yuwei , Shen Jun , Wei Dapeng , Wei Xianlong
Published: June 2020

On‐chip electron sources with the advantages of high emission current and density, high emission efficiency, low working voltage, and easy fabrication are highly desired for scaling down free electron‐based devices and systems, especially for realizing those on a chip, but remain challenging. Here, such an on‐chip electron source is reported simply based on electroformed silicon oxide between concentric graphene films on silicon oxide substrate. It is demonstrated that electron emission from an electron emitter can be driven by a low voltage about 11 V, and a high emission efficiency of 33.6%. An on‐chip electron source with 36 × 36 emitter array in an area of 594 × 594 µm2 exhibits an emission current up to 1 mA at 38 V working voltage, corresponding to a high emission density of 283 mA cm−2. Electron emission from the sources is thought to be generated from horizontal tunneling diodes formed in electroformed silicon oxide. Combined advantages of high emission current and density, high emission efficiency, low working voltage, and easy fabrication make this on‐chip electron sources promising in realizing miniature and on‐chip free electron‐based devices and systems.
Delayed bleeding complication due to internal mammary artery injury after ultrasound‐guided percutaneous catheter drainage for liver cyst infection
Authors: Arai Tomoyuki , Masuda Shinichiro , Nakano Tomotsugu , Hojo Rintaro , Tsuchiyama Takaaki , Fukamizu Seiji , Shibui Takashi
Published: June 2020

Background

Ultrasound‐guided percutaneous catheter drainage (PCD) is widely accepted as a primary treatment for pyogenic liver abscess. Severe PCD‐related complications have been reported; however, delayed bleeding complications due to internal mammary artery injury are unknown.

Case Presentation

An 84‐year‐old man undergoing hemodialysis owing to chronic kidney disease due to focal segmental glomerulosclerosis was admitted to our hospital for liver cyst infection. Ultrasound‐guided PCD was carried out through the normal liver at the upper abdominal midline at the level of the sixth intercostal space. Two days later, an abdominal hematoma occurred at the puncture site. Contrast‐enhanced computed tomography revealed extravasation of the distal right internal mammary artery, which was successfully treated with percutaneous coil embolization.

Conclusion

Internal mammary artery injury should be considered as a differential diagnosis when a progressing hematoma develops after PCD.
Chemo‐ and Regioselective Additions of Nucleophiles to Cyclic Carbonates for the Preparation of Self‐Blowing Non‐Isocyanate Polyurethane Foams
Authors: Monie Florent , Grignard Bruno , Thomassin Jean‐Michel , Mereau Raphael , Tassaing Thierry , Jerome Christine , Detrembleur Christophe
Published: June 2020

Polyurethane (PU) foams are indisputably daily essential materials found in many applications, notably for comfort (for example, matrasses) or energy saving (for example, thermal insulation). Today, greener routes for their production are intensively searched for to avoid the use of toxic isocyanates. An easily scalable process for the simple construction of self‐blown isocyanate‐free PU foams by exploiting the organocatalyzed chemo‐ and regioselective additions of amines and thiols to easily accessible cyclic carbonates is described. These reactions are first validated on model compounds and rationalized by DFT calculations. Various foams are then prepared and characterized in terms of morphology and mechanical properties, and the scope of the process is illustrated by modulating the composition of the reactive formulation. With impressive diversity and accessibility of the main components of the formulations, this new robust and solvent‐free process could open avenues for construction of more sustainable PU foams, and offers the first realistic alternative to the traditional isocyanate route.
Enzymatically Formed Peptide Assemblies Sequestrate Proteins and Relocate Inhibitors to Selectively Kill Cancer Cells
Authors: He Hongjian , Liu Shuang , Wu Difei , Xu Bing
Published: June 2020

Herein, we show that an enzymatic reaction can generate peptide assemblies that sequestrate proteins to selectively kill cancer cells. A phosphopeptide bearing the antagonistic motif (AVPI) to the inhibitors of apoptotic proteins (IAPs) enters cancer cells and normal cells by caveolin‐dependent endocytosis and macropinocytosis, respectively. The AVPI‐bearing peptide assemblies sequestrates IAPs and releases bortezomib (BTZ), a proteasome inhibitor, in the cytosol of cancer cells, but rescues the normal cells (namely, HS‐5 cells) by trafficking the BTZ into lysosomes. Alkaline phosphatase (ALP) acts as a context‐dependent signal for trafficking the peptide/BTZ assemblies and selectively induces the death of the cancer cells. The assemblies of AVPI exhibit enhanced proteolytic resistance. This work, which utilizes the difference in endocytic uptake of enzymatically formed peptide assemblies to selectively kill cancer cells, promises a new way to develop selective cancer therapeutics.
Self‐Sorting Supramolecular Polymerization: Helical and Lamellar Aggregates of Tetra‐Bay‐Acyloxy Perylene Bisimide
Authors: Hecht Markus , Leowanawat Pawaret , Gerlach Tabea , Stepanenko Vladimir , Stolte Matthias , Lehmann Matthias , Würthner Frank
Published: June 2020

A new perylene bisimide (PBI), with a fluorescence quantum yield up to unity, self‐assembles into two polymorphic supramolecular polymers. This PBI bears four solubilizing acyloxy substituents at the bay positions and is unsubstituted at the imide position, thereby allowing hydrogen‐bond‐directed self‐assembly in nonpolar solvents. The formation of the polymorphs is controlled by the cooling rate of hot monomer solutions. They show distinctive absorption profiles and morphologies and can be isolated in different polymorphic liquid‐crystalline states. The interchromophoric arrangement causing the spectral features was elucidated, revealing the formation of columnar and lamellar phases, which are formed by either homo‐ or heterochiral self‐assembly, respectively, of the atropoenantiomeric PBIs. Kinetic studies reveal a narcissistic self‐sorting process upon fast cooling, and that the transformation into the heterochiral (racemic) sheetlike self‐assemblies proceeds by dissociation via the monomeric state.
A Robust Porous Quinoline Cage: Transformation of a [4+6] Salicylimine Cage by Povarov Cyclization
Authors: Alexandre Pierre‐Emmanuel , Zhang Wen‐Shan , Rominger Frank , Elbert Sven M. , Schröder Rasmus R. , Mastalerz Michael
Published: June 2020

Porous shape‐persistent organic cages have become the object of interest in recent years because they are soluble and thus processable from solution. A variety of cages can be achieved by applying dynamic covalent chemistry (DCC), but they are less chemically stable. Here the transformation of a salicylimine cage into a quinoline cage by a twelve‐fold Povarov reaction as the key step is described. Besides the chemical stability of the cage over a broad pH regime, it shows a unique absorption and emission depending on acid concentration. Furthermore, thin films for the vapor detection of acids were investigated, showing color switches from pale‐yellow to red, and characteristic emission profiles.
Modulating Electrostatic Interactions in Ion Pair Intermediates To Alter Site Selectivity in the C−O Deoxygenation of Sugars
Authors: Lowe Jared M. , Bowers Bekah E. , Seo Youngran , Gagné Michel R.
Published: June 2020

Controlling which products one can access from the predefined biomass‐derived sugars is challenging. Changing from CH2Cl2 to the greener alternative toluene alters which C−O bonds in a sugar are cleaved by the tris(pentafluorophenyl)borane/HSiR3 catalyst system. This increases the diversity of high‐value products that can be obtained through one‐step, high‐yielding, catalytic transformations of the mono‐, di‐, and oligosaccharides. Computational methods helped identify this non‐intuitive outcome in low dielectric solvents to non‐isotropic electrostatic enhancements in the key ion pair intermediates, which influence the reaction coordinate in the reactivity‐/selectivity‐determining step. Molecular‐level models for these effects have far‐reaching consequences in stereoselective ion pair catalysis.
Palladium(II)‐Catalyzed Enantioselective Azidation of Unactivated Alkenes
Authors: Li Xiaonan , Qi Xiaoxu , Hou Chuanqi , Chen Pinhong , Liu Guosheng
Published: June 2020

The first Pd‐catalyzed enantioselective azidation of unactivated alkenes has been established by using readily accessible 1‐azido‐1,2‐benziodoxol‐3(1H)‐one (ABX) as an azidating reagent, which affords a wide variety of structurally diverse 3‐N3‐substituted piperidines in good yields with excellent enantioselectivity. The reaction features good functional‐group compatibility and mild reaction conditions. Notably, both an electrophilic azidating reagent and the sterically bulky chiral pyridinyl‐oxazoline (Pyox) ligand are crucial to the successful reaction.
Spidroin‐Inspired, High‐Strength, Loofah‐Shaped Protein Fiber for Capturing Uranium from Seawater
Authors: Yu Qiuhan , Yuan Yihui , Feng Lijuan , Feng Tiantian , Sun Wenyan , Wang Ning
Published: June 2020

The unique three‐dimensional structure of spidrion determines the outstanding mechanical properties of the spider silk fiber. Inspired by the similarity of the three‐dimensional structure of superb‐uranyl binding protein (SUP) to that of spidroin, a dual‐SUP (DSUP) chimeric protein fiber with high tensile strength is designed. The DSUP hydrogel fiber exhibits a loofah‐shape structure by the cross‐interaction of the protein nanofiber. Full exposure of abundant functional uranyl‐binding sites in the stretchable loofah‐shape hydrogel protein fiber give the DSUP fiber a groundbreaking uranium extraction capacity of 17.45 mg g−1 with an ultrashort saturation time of 3 days in natural seawater. This work reports the design of an adsorbent with ultrahigh uranium extraction capacity and explores a strategy for fabricating artificial high‐strength functional non‐spidroin protein fiber.
Metal–Organic Framework Disintegrants: Enzyme Preparation Platforms with Boosted Activity
Authors: An Hongde , Song Jie , Wang Ting , Xiao Nannan , Zhang Zhenjie , Cheng Peng , Ma Shengqian , Huang He , Chen Yao
Published: June 2020

An enzyme formulation using customized enzyme activators (metal ions) to directly construct metal–organic frameworks (MOFs) as enzyme protective carriers is presented. These MOF carriers can also serve as the disintegrating agents to simultaneously release enzymes and their activators during biocatalysis with boosted activities. This highly efficient enzyme preparation combines enzyme immobilization (enhanced stability, easy operation) and homogeneous biocatalysis (fast diffusion, high activity). The MOF serves as an ion pump that continuously provides metal ion activators that greatly promote the enzymatic activities (up to 251 %). This MOF–enzyme composite demonstrated an excellent protective effect against various perturbation environments. A mechanistic investigation revealed that the spontaneous activator/enzyme release and ion pumping enable enzymes to sufficiently interact with their activators owing to the proximity effects, leading to a boost in biocatalytic performance.
Green highly sensitive spectrofluorimetric method for rapid determination of tafluprost in its pure form and ophthalmic formulation
Authors: Abd‐AlGhafar Walaa Nabil , Saad Samar , Sheribah Zainab , Aly Fatma
Published: June 2020

A green, simple and easy spectrofluorimetric method was studied for rapid estimation of tafluprost (TFL). The native fluorescence of TFL was measured at 292 nm after excitation at 220 nm. The results were linear in water over the concentration range 50–600 ng ml−1 with a correlation coefficient r = 0.9999 and intercept 1.1555. The limit of detection and limit of quantification were found to be 7.87 and 23.86 ng ml−1, respectively. Neither different pH nor surfactants enhanced the fluorescence intensity. The high sensitivity of this spectrofluorimetric method makes it suitable for analysis of low concentrations of tafluprost in commercially available ophthalmic formulations. This procedure was validated according to International Council for Harmonisation Guidelines.
Tris‐{hydridotris(1‐pyrazolyl)borato}actinide Complexes: Synthesis, Spectroscopy, Crystal Structure, Bonding Properties and Magnetic Behaviour
Authors: Apostolidis Christos , Kovács Attila , Walter Olaf , Colineau Eric , Griveau Jean‐Christophe , Morgenstern Alfred , Rebizant Jean , Caciuffo Roberto , Panak Petra J. , Rabung Thomas , Schimmelpfennig Bernd , Perfetti Mauro
Published: June 2020

The isostructural compounds of the trivalent actinides uranium, neptunium, plutonium, americium, and curium with the hydridotris(1‐pyrazolyl)borato (Tp) ligand An[η3‐HB(N2C3H3)3]3(AnTp3) have been obtained through several synthetic routes. Structural, spectroscopic (absorption, infrared, laser fluorescence) and magnetic characterisation of the compounds were performed in combination with crystal field, density functional theory (DFT) and relativistic multiconfigurational calculations. The covalent bonding interactions were analysed in terms of the natural bond orbital (NBO) and quantum theory of atoms in molecules (QTAIM) models.
Probing the Origin of Adaptive Aromaticity in 16‐Valence‐Electron Metallapentalenes
Authors: Chen Dandan , Szczepanik Dariusz W. , Zhu Jun , Solà Miquel
Published: June 2020

Species with adaptive aromaticity are aromatic in the ground and lowest‐lying triplet excited states and they have normally intermediate singlet‐triplet gaps. Few examples of compounds with adaptive aromaticity are known to date, including 16‐valence‐electron (16e) metallapentalenes. A sweeping search could be conducted to discover new members of this group, but efficient designs with an explicit strategy would facilitate the quest for new members of this elusive family. Density functional theory calculations and aromaticity evaluations have been performed to reveal the nature of triplet‐state aromaticity in 16e metallapentalenes. Our results show that coordination of strong σ‐ or π‐donor ligands helps achieving adaptive aromaticity of 16e metallapentalenes by means of a spin delocalization mechanism. These results have important implications for understanding the unusual properties of the organometallic adaptive aromatics, leading the way to efficient design of new compounds with tunable singlet‐triplet gaps.
N‐Rich Porous Polymer with Isolated Tb3+‐Ions Displays Unique Temperature Dependent Behavior through the Absence of Thermal Quenching
Authors: Vanden Bussche Flore , Kaczmarek Anna M. , Veerapandian Savita K. P. , Everaert Jonas , Debruyne Maarten , Abednatanzi Sara , Morent Rino , De Geyter Nathalie , Van Speybroeck Veronique , Van Der Voort Pascal , Stevens Christian V.
Published: June 2020

The challenge of measuring fast moving or small scale samples is based on the absence of contact between sample and sensor. Grafting lanthanides onto hybrid materials arises as one of the most promising accurate techniques to obtain noninvasive thermometers. In this work, a novel bipyridine based porous organic polymer (bpyDAT POP) was investigated as temperature sensor after grafting with Eu(acac)3 and Tb(acac)3 complexes. The bpyDAT POP successfully showed temperature‐dependent behavior in the 10–310 K range, proving the potential of amorphous, porous organic frameworks. We observed unique temperature dependent behavior. More intriguingly, instead of the standard observed change in emission as a result of a change in temperature for both Eu3+ and Tb3+, the emission spectrum of Tb3+ remained constant. This work provides framework‐ and energy‐based explanations for the observed phenomenon. The conjugation in the bpyDAT POP framework is interrupted, creating energetically isolated Tb3+ environments. Energy transfer from Tb3+ to Eu3+ is therefore absent, nor energy back transfer from Tb3+ to bpyDAT POP ligand (i.e. no thermal quenching) is detected.
Transition Metal‐Catalyzed Intermolecular Cascade C−H Activation/Annulation Processes for the Synthesis of Polycycles
Authors: Song Liangliang , Van der Eycken Erik V.
Published: June 2020

Polycycles are abundantly present in numerous advanced chemicals, functional materials, bioactive molecules and natural products. However, the strategies for the synthesis of polycycles are limited to classical reactions and transition metal‐catalyzed cross‐coupling reactions, requiring pre‐functionalized starting materials and lengthy synthetic operations. The emergence of novel approaches shows great promise for the fields of organic/medicinal/materials chemistry. Among them, transition metal‐catalyzed C−H activation followed by intermolecular annulation reactions prevail, due to their straightforward manner with high atom‐ and step‐economy, providing rapid, concise and efficient methods for the construction of diverse polycycles. Several strategies have been developed for the synthesis of polycycles, relying on sequential multiple C−H activation/annulation, or combination of C−H activation/annulation and further interaction with a proximal group, or merger of C−H activation with a cycloaddition reaction, or in situ formation of the directing group. These are attractive, efficient, step‐ and atom‐economic methods starting from commercially available materials. This Minireview will provide an introduction to transition metal‐catalyzed C−H activation for the synthesis of polycycles, helping researchers to discover indirect connections and reveal hidden opportunities. It will also promote the discovery of novel synthetic strategies relying on C−H activation.
Modulating Hierarchical Micro/Mesoporosity by a Mixed Solvent Approach in Al‐MOF: Stabilization of MAPbBr3 Quantum Dots
Authors: Laha Subhajit , Rambabu Darsi , Bhattacharyya Sohini , Maji Tapas Kumar
Published: June 2020

Various hierarchical micro/mesoporous MOFs based on {[Al(μ‐OH)(1,4‐NDC)]⋅H2O} (MOF1) with tunable porosities (pore volume and surface area) have been synthesized by assembling AlIII and 1,4‐NDC (1,4‐naphthalenedicarboxylate) under microwave irradiation by varying water/ethanol solvent ratio. Water/ethanol mixture has played a crucial role in the mesopore generation in MOF1M25, MOF1M50, and MOF1M75, which is achieved by in situ formation of water/ethanol clusters. By adjusting the ratio of water/ethanol, the particle size, surface area and micro/mesopore volume fraction of the MOFs are controlled. Furthermore, reaction time plays a critical role in mesopore formation as realized by varying reaction time for the MOF with 50 % ethanol (MOF1M50). Additionally, hierarchical MOF (MOF1M50) has been used as a template for the stabilization of MAPbBr3 (MA=methylammonium) perovskite quantum dots (PQDs). MAPbBr3 PQDs are grown inside MOF1M50, where mesopores control the size of PQDs which leads to quantum confinement.
Influence of Ligand and Nuclearity on the Cytotoxicity of Cyclometallated C^N^C Platinum(II) Complexes
Authors: Kergreis Angélique , Lord Rianne M. , Pike Sarah J.
Published: June 2020

A series of cyclometallated mono‐ and di‐nuclear platinum(II) complexes and the parent organic ligand, 2,6‐diphenylpyridine 1 (HC^N^CH), have been synthesized and characterized. This library of compounds includes [(C^N^C)PtII(L)] (L=dimethylsulfoxide (DMSO) 2 and triphenylphosphine (PPh3) 3) and [((C^N^C)PtII)2(L‘)] (where L‘=N‐heterocycles (pyrazine (pyr) 4, 4,4‘‐bipyridine (4,4‘‐bipy) 5 or diphosphine (1,4‐bis(diphenylphosphino)butane (dppb) 6). Their cytotoxicity was assessed against four cancerous cell lines and one normal cell line, with results highlighting significantly increased antiproliferative activity for the dinuclear complexes (4–6), when compared to the mononucleated species (2 and 3). Complex 6 is the most promising candidate, displaying very high selectivity towards cancerous cells, with selectivity index (SI) values >29.5 (A2780) and >11.2 (A2780cisR), and outperforming cisplatin by >4‐fold and >18‐fold, respectively.
Catalytic Transfer Hydrogenation of Arenes and Heteroarenes
Authors: Gelis Coralie , Heusler Arne , Nairoukh Zackaria , Glorius Frank
Published: June 2020

Transfer hydrogenation reactions are of great interest to reduce diverse molecules under mild reaction conditions. To date, this type of reaction has only been successfully applied to alkenes, alkynes and polarized unsaturated compounds such as ketones, imines, pyridines, etc. The reduction of benzene derivatives by transfer hydrogenation has never been described, which is likely due to the high energy barrier required to dearomatize these compounds. In this context, we have developed a catalytic transfer hydrogenation reaction for the reduction of benzene derivatives and heteroarenes to form complex 3‐dimensional scaffolds bearing various functional groups at room temperature without needing compressed hydrogen gas.
Understanding the Role of Chalcogens in Ether‐Based Luminophores with Aggregation‐Induced Fluorescence and Phosphorescence
Authors: Riebe Steffen , Wölper Christoph , Balszuweit Jan , Hayduk Matthias , Gutierrez Suburu Matias Ezequiel , Strassert Cristian A. , Doltsinis Nikos L. , Voskuhl Jens
Published: June 2020

The front cover artwork is provided by the group of Jun.‐Prof. Dr. Jens Voskuhl [Universität Duisburg‐Essen (UDE), Germany]. The cover image shows deep‐sea frog fishes known to attract their prey by using a light emitting organ. Here we adapted the illustration by adding the corresponding chalcogen as a lantern, shining in the corresponding emission colour as described in the contribution. Read the full text of the Article at 10.1002/cptc.202000002.
Development of a multi‐residue high‐throughput UHPLC–MS/MS method for routine monitoring of SARM compounds in equine and bovine blood
Authors: Ventura Emiliano , Gadaj Anna , Buckley Tom , Mooney Mark H.
Published: June 2020

Selective androgen receptor modulators (SARMs) are a group of anabolic enhancer drugs posing threats to the integrity of animal sports and the safety of animal‐derived foods. The current research describes for the first time the development of a semi‐quantitative assay for the monitoring of SARM family compounds in blood and establishes the relative stability of these analytes under various storage conditions prior to analysis. The presented screening method validation was performed in line with current EU legislation for the inspection of livestock and produce of animal origin, with detection capability (CCβ) values determined at 0.5 ng/mL (Ly2452473), 1 ng/mL (AC‐262536 and PF‐06260414), 2 ng/mL (bicalutamide, GLPG0492, LGD‐2226, ostarine, S‐1, S‐6, and S‐23), and 5 ng/mL (andarine, BMS‐564929, LGD‐4033, RAD140, and S‐9), respectively. The applicability of the developed assay was demonstrated through the analysis of blood samples from racehorses and cattle. The developed method presents a high‐throughput cost‐effective tool for the routine screening for a range of SARM compounds in sport and livestock animals.
Iridium‐Catalyzed Carbenoid Insertion of Sulfoxonium Ylides for Synthesis of Quinoxalines and β‐Keto Thioethers in Water
Authors: Xu Yingying , Huang Xin , Lv Guanghui , Lai Ruizhi , Lv Songyang , Li Jianglian , Hai Li , Wu Yong
Published: June 2020

Sulfoxonium ylides as safe carbene precursors are described for iridium‐catalyzed carbene insertions and annulation, providing a facile and green approach to access a variety of quinoxaline derivatives in water. This water‐mediated method also allows the preparation of β‐keto thioethers under mild condition.
Design of secure session key using unique addressing and identification scheme for smart home Internet of Things network
Authors: Kumar Pankaj , Chouhan Lokesh
Published: June 2020

Internet of Things (IoT) defines as internetworks of physical smart devices embedded with electronic software, sensors, actuators, and network connectivity. Due to an increase in the number of smart devices, objects, and appliances, the existing addressing schemes and security protocols cannot guaranty to perform well in all situations. The main requirement includes a unique secure unique addressing scheme that ensures data privacy and reliable communication in the IoT system. In this article, a secure session key unique addressing and identification scheme proposed by modifying the standard IPv6 protocol. The proposed scheme provides a unique way of assigning the addressing for smart devices/appliances and uniquely authenticates them at the destination end. In addition, this scheme also establishes a secure session and mutual authentication by using the Diffie‐Hellman key exchange protocol. The network simulation of the proposed scheme simulates network throughput and end‐to‐end delay. Moreover, the informal security verification and formal security analysis with the help of the ROR model carried out in this work. This analysis proves that the proposed scheme is safe against various possible attacks, for example, device impersonation, password guessing, man‐in‐the‐middle, attacks replay, masquerade attacks, maintain anonymity, and secure end to end mutual authentication.
Anwendung von Werkzeugverschleißtests zur Qualitätssicherung von Bahnschotter
Authors: Latal Christine , Bach Holger , Thuro Kurosch
Published: June 2020

The resistance of aggregates to abrasion estimated by the Micro‐Deval test is an important mechanical parameter for aggregates used as railway ballast. At present, testing intervals are sparse due to the cost of the tests. Cost‐efficient testing methods would be greatly appreciated. A detailed study of the applicability of alternative testing methods, as commonly used to estimate the potential of a rock or soil to cause wear to a tool (LCPC Abroy test and Cerchar test), demonstrates the advantage of implementing these testing methods in addition to the recommended tests.
Numerische Studien zur Sicherung von Baugruben und Geländesprüngen mit Stützscheiben
Authors: Marte Roman , Choosrithong Kamchai , Schweiger Helmut F.
Published: June 2020

In diesem Beitrag wird die innere und äußere Tragwirkung von Sicherungen von Geländesprüngen mittels Stützscheiben bzw. schalenartig wirkenden Tragwerken numerisch untersucht. Solche Lösungsansätze zur Sicherung, z. B. von Baugrubenböschungen, können zum Einsatz kommen, wenn der Einbau von Zugelementen wie Anker oder Nägel, z. B. aufgrund von eingeschränkter Nutzbarkeit von Nachbargrundstücken, nicht möglich oder gewollt ist. Stützscheiben können durch überschnittene Großbohrpfähle, DSV‐Säulen oder Einmischelemente hergestellt werden. Der Nachweis der äußeren Tragfähigkeit erfolgt dabei im Allgemeinen durch ein vereinfachtes analytisches Verfahren, der sog. Palisadentheorie. Ein Nachweis der inneren Tragfähigkeit ist mit analytischen Verfahren praktisch kaum möglich. In den in diesem Beitrag diskutierten numerischen Untersuchungen wird das große Optimierungspotenzial derartiger Tragsysteme in Bezug auf die äußere Tragfähigkeit aufgezeigt, und auf Basis geeigneter Stoffmodelle für Boden und Baumaterial für die Stützscheiben wird die innere Tragwirkung derartiger Systeme eingehend diskutiert. Zusammenfassend wird aufgezeigt, dass bei Anwendung dreidimensionaler numerischer Berechnungsmethoden mit geeigneten Stoffmodellen, ein großes Einsparungspotenzial in der Dimensionierung derartiger Stützsysteme möglich ist.
Modelling suspended sediment discharge in a glaciated Arctic catchment–Lake Peters, Northeast Brooks Range, Alaska
Authors: Thurston Lorna Louise , Schiefer Erik , McKay Nicholas P. , Kaufman Darrell S.
Published: June 2020

Seasonal suspended sediment transfer in glaciated catchments is responsive to meteorological, geomorphological, and glacio‐fluvial conditions, and thus is a useful indicator of environmental system dynamics. Knowledge of multifaceted fluvial sediment‐transfer processes is limited in the Alaskan Arctic – a region sensitive to contemporary environmental change. For two glaciated sub‐catchments at Lake Peters, northeast Brooks Range, Alaska, we conducted a two‐year endeavour to monitor the hydrology and meteorology, and used the data to derive multiple‐regression models of suspended sediment load. Statistical selection of the best models shows that incorporating meteorological or temporal explanatory variables improves performances of turbidity‐ and discharge‐based sediment models. The resulting modelled specific suspended sediment yields to Lake Peters are: 33 (20–60) t km−2 yr−1 in 2015, and 79 (50–140) t km−2 yr−1 in 2016 (95% confidence band estimates). In contrast to previous studies in Arctic Alaska, fluvial suspended sediment transfer to Lake Peters was primarily influenced by rainfall, and secondarily influenced by temperature‐driven melt processes associated with clockwise diurnal hysteresis. Despite different sub‐catchment glacier coverage, specific yields were the same order of magnitude from the two primary inflows to Lake Peters, which are Carnivore Creek (128 km2; 10% glacier coverage) and Chamberlin Creek (8 km2; 23% glacier coverage). Seasonal to longer‐term sediment exhaustion and/or contrasting glacier dynamics may explain the lower than expected relative specific sediment yield from the more heavily glacierized Chamberlin Creek catchment. Absolute suspended sediment yield (t yr−1) from Carnivore Creek to Lake Peters was 27 times greater than from Chamberlin Creek, which we attribute to catchment size and sediment supply differences. Our results provide a foundational understanding of the current sediment transfer regime and are useful for predicting changes in fluvial sediment transport in glaciated Alaskan Arctic catchments.
A four‐year longitudinal study of the impact on learning structure on dental student lifestyle values
Authors: Vinton JC
Published: June 2020

Acquiring values is an important part in the education of dental students. This study describes how the values of 109 dental students changed over four years in the dental school's learning environment. Data describe the dental school learning environment as highly teacher‐centered, in which authority is vested in faculty, in which activities are highly programmed, and in which communication is one‐way, teacher‐to‐student. The data also indicate significant changes in dental students' values after four years in this environment. Learning from and sharing with others, interpersonal communication, and close relationships with others are valued less by students while more value is placed on their own interests and goals.