bluuebunny/crossref_metadata_2025 huggingface dataset:
Mitochondrial respiration atlas reveals differential changes in mitochondrial function across sex and age
Authors: Sarver Dylan C , Saqib Muzna , Chen Fangluo , Wong G William
Published: November 2024

Organ function declines with age, and large-scale transcriptomic analyses have highlighted differential aging trajectories across tissues. The mechanism underlying shared and organ-selective functional changes across the lifespan, however, still remains poorly understood. Given the central role of mitochondria in powering cellular processes needed to maintain tissue health, we therefore undertook a systematic assessment of respiratory activity across 33 different tissues in young (2.5 months) and old (20 months) mice of both sexes. Our high-resolution mitochondrial respiration atlas reveals: 1) within any group of mice, mitochondrial activity varies widely across tissues, with the highest values consistently seen in heart, brown fat, and kidney; 2) biological sex is a significant but minor contributor to mitochondrial respiration, and its contributions are tissue-specific, with major differences seen in the pancreas, stomach, and white adipose tissue; 3) age is a dominant factor affecting mitochondrial activity, especially across most brain regions, different fat depots, skeletal muscle groups, eyes, and different regions of the gastrointestinal tract; 4) age-effects can be sex- and tissue-specific, with some of the largest effects seen in pancreas, heart, adipose tissue, and skeletal muscle; and 5) while aging alters the functional trajectories of mitochondria in a majority of tissues, some are remarkably resilient to age-induced changes. Altogether, our data provide the most comprehensive compendium of mitochondrial respiration and illuminate functional signatures of aging across diverse tissues and organ systems.
Dynamics of compartment-specific proteomic landscapes of hepatotoxic and cholestatic models of liver fibrosis
Authors: Jirouskova Marketa , Harant Karel , Cejnar Pavel , Ojha Srikant , Korelova Katerina , Sarnova Lenka , Sticova Eva , Mayr Christoph , Schiller Herbert , Gregor Martin
Published: November 2024

Accumulation of extracellular matrix (ECM) in liver fibrosis is associated with changes in protein abundance and composition depending upon etiology of the underlying liver disease. Current efforts to unravel etiology- specific mechanisms and pharmacological targets rely on several models of experimental fibrosis. Here, we characterize and compare dynamics of hepatic proteome remodeling during fibrosis development and spontaneous healing in experimental models of hepatotoxic (CCl
4
intoxication) and cholestatic (3,5- diethoxycarbonyl-1,4-dihydrocollidine (DDC) feeding) injury. Using detergent-based tissue extraction and mass spectrometry, we identified compartment-specific changes in the liver proteome with detailed attention to ECM composition and changes in protein solubility. Our analysis yielded unique time-resolved CCl
4
and DDC signatures underscoring restricted healing with higher carcinogenic potential upon cholestasis. Correlation of protein abundance profiles with fibrous deposits revealed extracellular chaperone clusterin with implicated role in fibrosis resolution. Dynamics of clusterin expression was validated in the context of human liver fibrosis. Atomic force microscopy of fibrotic livers complemented proteomics with profiles of disease-associated changes in local liver tissue mechanics. This study determined compartment-specific proteomic landscapes of liver fibrosis and delineated etiology-specific ECM components, providing thus a foundation for future antifibrotic therapies.
Estrategia para fortalecer identidad de Cencosud Shopping Center respecto a
las otras empresas del holding
Authors:   , Díaz Saintard Loreto
Published: November 2024

Cencosud Shopping Centers es la filial del grupo Cencosud, que se dedica a
los centros comerciales. Nace en 1982 en Argentina y en Chile con Alto las
Condes en 1993. En 2019 Shopping Centers fue listada en la Bolsa de Comercio de
Santiago, y cuenta con operaciones en Chile, Perú y Colombia.
En este caso trabajaremos en la operación de Chile donde es el segundo operador
de centros comerciales, propietario y operador de 33 centros comerciales con
presencia en 7 regiones, con 97% de locales ocupados, con sobre 1 millón de m2
construidos y 500 trabajadores.
Shopping Centers vive cambios por sucesión familiar y nuevos liderazgos
ejecutivos.
Además, se suman anuncios de expansión e inversiones para nuevos proyectos.
Shopping Centers no ha abierto nuevos locales desde el año 2012.
Este cambio se ve como una oportunidad para fortalecer la identidad de la
empresa con nuevos atributos, en un contexto de cambio para la industria, donde
debe convivir la experiencia física con la digital.
En un periodo de cambio se busca que los trabajadores conozcan lo que es
Cencosud Shopping Centers y se identifiquen con la nueva identidad de la
empresa, la que es resultado de los cambios de la organización y entorno.
LINEAMIENTOS ESTRATÉGICOS
• Incorporar a los trabajadores en la identidad de la organización.
• Fortalecer identidad de Shopping Center respecto a las otras empresas del
holding.
• Informar a los trabajadores de los cambios, disminuyendo incertidumbre.
• Facilitar la adaptación de los trabajadores a nuevos liderazgos por sucesión
familiar.

KPI ESTRATÉGICO
Medir el nivel de conocimiento e identificación de los trabajadores con la
identidad de la empresa.

Plan de Acción:
Se extiende entre enero 2024 y diciembre 2024, y abordará las siguientes
dimensiones:
-Incorporación de los trabajadores como actores clave en los pilares
estratégicos de la empresa, y su papel en el logro de resultados con el
desarrollo de un discurso corporativo coherente.
-Fortalecimiento de la identidad respecto a otras empresas del holding,
indagación de aspectos identitarios que generan orgullo en las personas y
sentido de pertenencia, y su instalación en los trabajadores para lograr
diferenciación con otras unidades de negocio de la compañía.
-Identificación y evaluación de la comunicación interna, canales de escucha e
identificación de liderazgos para su uso con el fin del logro del objetivo
estratégico.
-Generar una planificación informativa que contenga los nuevos contenidos, que
considere una co-creación de los mensajes, y eduque y armonice a los actores
para la gestión del cambio.
La influencia del temperamento y el sexo en juegos de control inhibitorio :
recompensas predictivas y no predictivas
Authors:   , Caffarena Barcenilla Carolina
Published: November 2024

Esta tesis tiene por objetivo general evaluar la influencia conductual y
neurofisiológica de las estrategias de Recompensa Predictiva y No Predictiva
ofrecidas en un juego, el Temperamento y el Sexo, en el Control Inhibitorio en
niños de 4 a 5 años. Para aproximarse a la temática se elaboró un estado del
arte sobre las habilidades de autorregulación infantil, sus hitos del desarrollo
y los factores intervinientes (primer artículo). El diseño metodológico
utilizado fue de corte transeccional, de tipo no experimental y diseño
correlacional que consideró 149 niños y niñas de 4 a 5 años. Los instrumentos
utilizados fueron 2 juegos de Tablet diseñados para el estudio y un cuestionario
de temperamento infantil del cual se realizó un análisis psicométrico en una
muestra de la población chilena (segundo artículo). La parte empírica del
estudio se realizó en dos etapas, en primer lugar, se realizó una medición
conductual de los niños y niñas participantes (tercer artículo), y en segundo
lugar, se evaluó el correlato neuronal del control inhibitorio en presencia de
ambos tipos de recompensa en una submuestra de 16 niños y niñas. Los principales
hallazgos señalan que la influencia de los diferentes tipos de recompensa sobre
el control inhibitorio, en la muestra estudiada responde de manera distinta a
grupos etarios de mayor edad. Así también, se menciona que el temperamento y el
sexo influyen sobre la respuesta inhibitoria. Finalmente, el trabajo que aquí se
presenta concluye con una síntesis integrada de los resultados obtenidos,
discutiendo la contribución del estudio, sus implicancias, sus limitaciones y
proyecciones futuras.
Forward-looking sonar ego-motion estimation using deep learning
Authors:   , Muñoz Rojas Bastián
Published: November 2024

Las operaciones de robótica submarina demandan capacidades precisas de
navegación y localización para una amplia gama de actividades, incluyendo mapeo,
inspección y exploración. Dado que los Sistemas de Posicionamiento Global (GPS)
no están disponibles bajo el agua, estas tareas generalmente dependen de
Sistemas de Navegacion Inercial (INS) y Registradores de Velocidad Doppler
(DVL). Desafortunadamente, estos sistemas son susceptibles a la deriva y
errores, y sus variantes de bajo error a menudo plantean desafíos de integración
significativos y costos, especialmente en vehículos más pequeños.
Esta tesis explora la aplicación de una cámara acústica, conocida en inglés como
Forward-Looking Sonar (FLS) para tareas de navegación, con un enfoque específico
en la estimación de odometría a través del Aprendizaje Profundo (DL, por sus
siglas en inglés). Con este fin, se desarrolla un marco de datos integral para
la recopilación y gestión de datos FLS tanto sintéticos como de terreno. Basadas
en el estado del arte, se proponen dos arquitecturas distintas de aprendizaje
profundo diseñadas para estimar el movimiento propio entre imágenes FLS. Se
implementó un procedimiento para el entrenamiento y evaluación de estos modelos,
considerando particularmente la escasez de datos de terreno.
Los hallazgos de este estudio demuestran que las arquitecturas propuestas,
cuando se entrenan con datos sintéticos, pueden aprender la relación entre
imágenes FLS y el movimiento propio correspondiente. Importantemente, este
aprendizaje se puede generalizar a datos del mundo real. Además, los resultados
sugieren que estos modelos podrían beneficiarse de un proceso de ajuste fino
utilizando un subconjunto de datos de terreno. Este trabajo contribuye de manera
significativa a la comprensión y avance de los sistemas de navegación basados en
FLS en la robótica submarina.
WNK1 kinase is essential for insulin‐stimulated GLUT4 trafficking in skeletal muscle
Authors: Kim Ji‐Hee , Kim Hanul , Hwang Kyu‐Hee , Chang Jae Seung , Park Kyu‐Sang , Cha Seung‐Kuy , Kong In Deok
Published: September 2018

With‐no‐lysine 1 (WNK1) kinase is a substrate of the insulin receptor/Akt pathway. Impaired insulin signaling in skeletal muscle disturbs glucose transporter 4 (GLUT4) translocation associated with the onset of type 2 diabetes (T2D). WNK1 is highly expressed in skeletal muscle. However, it is currently unknown how insulin signaling targeting WNK1 regulates GLUT4 trafficking in skeletal muscle, and whether this regulation is perturbed in T2D. Hereby, we show that insulin phosphorylates WNK1 at its activating site via a phosphatidylinositol 3‐kinase‐dependent mechanism. WNK1 promotes the cell surface abundance of GLUT4 via regulating TBC1D4. Of note, we observed insulin resistance and decreased WNK1 phosphorylation in T2D db/db mice as compared to the control mice. These results provide a new perspective on WNK1 function in the pathogenesis of hyperglycemia in T2D.
Performance guaranteed fault control of uncertain constrained nonaffine systems under input quantization and actuation failures
Authors: Shen Zhixi , Zhang Tianfeng , Song Yongduan , Yu Wei
Published: September 2018

This paper investigates the tracking control problem for a class of uncertain nonaffine system in the presence of input quantization and saturation yet possibly faulty actuators. A quantized robust adaptive fault‐tolerant control scheme capable of guaranteeing performance specifications is developed. By injecting quantizer parameters into the control design and using performance transformation, a constrained robust adaptive fault‐tolerant control scheme is developed to cope with modeling uncertainties, actuation saturation, and actuation faults, ensuring uniformly ultimately bounded stable tracking with the prescribed performance. The effectiveness of the proposed control strategy is confirmed by systematic stability analysis and simulation.
Solid State Processing of Aluminum Matrix Composites Reinforced with Nanoparticulate Materials
Authors: Leparoux Marc , Kollo Lauri , Kwon Hansang , Kallip Kaspar , Babu Nagumothu Kishore , AlOgab Khaled , Talari Mahesh Kumar
Published: September 2018

A simple powder metallurgy route is investigated at Empa for producing aluminum matrix nanocomposites. High energy ball milling has proven to be an efficient method for dispersing the nanoparticles into the matrix even up to high amount. The compaction of these blends at moderate temperature leads to dense nanocomposite materials with high strength whatever the nature of the reinforcement. Hot pressing, spark plasma sintering, and hot isostatic pressing induce the same tensile properties at rupture but higher yield strength can be observed for the simple hot pressing process. High strength can be only combined with high ductility for nanoparticle content below 1 vol%. These outstanding properties are achieved thanks to a homogenous nanoparticle dispersion as well as a bimodal grain size distribution with fine (<300 nm) and coarser grains (a few microns). The materials do not require subsequent heat or work hardening treatment and exhibit better or similar properties as the conventional high strength aluminum alloys. Finally, it is demonstrated that friction stir welding is a valuable process for joining these nanocomposites.
Enhancement of Mechanical and Electrical Properties in Al 6101 Alloy by Severe Shear Strain under Hydrostatic Pressure
Authors: Medvedev Andrey , Murashkin Maxim Yu. , Kazykhanov Vil , Valiev Ruslan Z. , Medvedev Alexander E. , Hodgson Peter D. , Lapovok Rimma
Published: September 2018

Samples of commercially received aluminum AA6101 alloy are homogenized, quenched, and subjected to 2, 4, and 8 passes of Equal Channel Angular Pressing (ECAP) with 200 MPa of applied backpressure. Tensile strength of the alloy's samples increases with the accumulated strain to the double value of 400 MPa after 8 ECAP passes, while electrical conductivity slightly decreases from 51.3 to 48.2%IACS. Aging at 130 °C for 72 h is used to restore conductivity with very small loss of strength. Moreover, the increase in conductivity is directly proportional to the number of ECAP passes and conductivity exceeds those values measured for the as‐received and solution treated states. Strong inhomogeneity of the microstructure and formation of a network of differently oriented shear bands during severe plastic deformation is observed, which is beneficial for simultaneous enhancement of mechanical and electrical properties.
Promise and Challenge of Phosphorus in Science, Technology, and Application
Authors: Han Xinpeng , Han Jinpeng , Liu Cheng , Sun Jie
Published: September 2018

Tremendous progress has been made in scientific research and application of phosphorus allotropes and their hybrid materials in recent decades. In particular, nanomaterial design has emerged as a promising solution to tackle many fundamental problems in conventional materials. This review discusses phosphorus‐based functional materials from the perspective of topological structures, which have several advantages such as good chemical stability, high surface areas, adjustable particle sizes and compositions, as well as various functionalities that enable a good performance in energy storage and conversion as well as other applications. Then, the progress on these functional materials for application in batteries, supercapacitors, catalysis, field‐effect transistors, optoelectronics, flexible electronics, sensors, biomedicine, etc., is discussed and summarized as well. Special attention is given to the research efforts to overcome the inherent shortcomings faced by red/black phosphorus. The aim is to elucidate the relationship between the phosphorus‐based topological structures and their performance. Finally, this review casts an insightful outlook on the future direction of the phosphorus‐based materials in nanotechnology.
Flexible MoS2‐Embedded Human Serum Albumin Hollow Nanocapsules with Long Circulation Times and High Targeting Ability for Efficient Tumor Ablation
Authors: Xu Chaoli , Teng Zhaogang , Zhang Yunlei , Yuwen Lihui , Zhang Qi , Su Xiaodan , Dang Meng , Tian Ying , Tao Jun , Bao Lei , Yang Bin , Lu Guangming , Zhu Jiang
Published: September 2018

Herein, MoS2‐embedded human serum albumin hollow nanocapsules (denoted MoS2/HSA) are successfully prepared via a hard‐core‐assisted layer‐by‐layer coating approach. The hollow MoS2/HSA nanocapsules possess an uniform size (280 nm), a larger hollow cavity, a low Young's modulus (222 ± 20 MPa), excellent photothermal conversion ability, and a high drug loading capacity for doxorubicin (27 wt%). The flexible hollow MoS2/HSA nanocapsules exhibit significantly enhanced cellular uptake efficiency against breast cancer cells duo to their flexible property and targeting ability of HSA. In vivo experiments show that the flexible MoS2/HSA could reduce phagocytosis and effectively improve blood persistence and tumor accumulation. In vitro and in vivo experiments have demonstrated that the flexible MoS2/HSA based nanoplatforms effectively ablate breast cancer cells via synergistic photothermal and chemical therapy.
Highly Active Nanoperovskite Catalysts for Oxygen Evolution Reaction: Insights into Activity and Stability of Ba0.5Sr0.5Co0.8Fe0.2O2+δ and PrBaCo2O5+δ
Authors: Kim Bae‐Jung , Cheng Xi , Abbott Daniel F. , Fabbri Emiliana , Bozza Francesco , Graule Thomas , Castelli Ivano E. , Wiles Luke , Danilovic Nemanja , Ayers Katherine E. , Marzari Nicola , Schmidt Thomas J.
Published: September 2018

It is shown that producing PrBaCo2O5+δ and Ba0.5Sr0.5Co0.8Fe0.2O2+δ nanoparticle by a scalable synthesis method leads to high mass activities for the oxygen evolution reaction (OER) with outstanding improvements by 10× and 50×, respectively, compared to those prepared via the state‐of‐the‐art synthesis method. Here, detailed comparisons at both laboratory and industrial scales show that Ba0.5Sr0.5Co0.8Fe0.2O2+δ appears to be the most active and stable perovskite catalyst under alkaline conditions, while PrBaCo2O5+δ reveals thermodynamic instability described by the density‐functional theory based Pourbaix diagrams highlighting cation dissolution under OER conditions. Operando X‐ray absorption spectroscopy is used in parallel to monitor electronic and structural changes of the catalysts during OER. The exceptional BSCF functional stability can be correlated to its thermodynamic meta‐stability under OER conditions as highlighted by Pourbaix diagram analysis. BSCF is able to dynamically self‐reconstruct its surface, leading to formation of Co‐based oxy(hydroxide) layers while retaining its structural stability. Differently, PBCO demonstrates a high initial OER activity while it undergoes a degradation process considering its thermodynamic instability under OER conditions as anticipated by its Pourbaix diagram. Overall, this work demonstrates a synergetic approach of using both experimental and theoretical studies to understand the behavior of perovskite catalysts.
Effect of Grain Cluster Size on Back‐Contact Perovskite Solar Cells
Authors: Lin Xiongfeng , Chesman Anthony S. R. , Raga Sonia R. , Scully Andrew D. , Jiang Liangcong , Tan Boer , Lu Jianfeng , Cheng Yi‐Bing , Bach Udo
Published: September 2018

Incorporating interdigitated back‐contact electrodes into organic–inorganic halide perovskite solar cells overcomes the optical losses and low architectural defect tolerance present in conventional “sandwich” cell configurations. However, other factors limit device performance in back‐contact architectures, such as the short charge‐carrier diffusion length within the perovskite film relative to the electrode spacing. As charge‐carrier diffusion length is crystal‐size related, in order to understand the effect of perovskite morphology on the performance of back‐contact perovskite solar cells (bc‐PSCs), perovskite films with four different grain cluster sizes, i.e., large, medium, small, and extra small, are fabricated via a solvent annealing approach. Crystallization of the perovskite is found to be closely related to the surface chemistry and topography of the substrate. The bc‐PSC photovoltaic performance correlates positively with the perovskite grain cluster size. Through a detailed analysis of transient photovoltage decay measurements, time‐resolved photoluminescence, and space charge‐limited current measurements, the effect of defect densities associated with grain cluster boundaries is elucidated.
Design of Hollow Nanostructures for Energy Storage, Conversion and Production
Authors: Wang Jiangyan , Cui Yi , Wang Dan
Published: September 2018

Hollow nanostructures have shown great promise for energy storage, conversion, and production technologies. Significant efforts have been devoted to the design and synthesis of hollow nanostructures with diverse compositional and geometric characteristics in the past decade. However, the correlation between their structure and energy‐related performance has not been reviewed thoroughly in the literature. Here, some representative examples of designing hollow nanostructure to effectively solve the problems of energy‐related technologies are highlighted, such as lithium‐ion batteries, lithium‐metal anodes, lithium–sulfur batteries, supercapacitors, dye‐sensitized solar cells, electrocatalysis, and photoelectrochemical cells. The great effect of structure engineering on the performance is discussed in depth, which will benefit the better design of hollow nanostructures to fulfill the requirements of specific applications and simultaneously enrich the diversity of the hollow nanostructure family. Finally, future directions of hollow nanostructure design to solve emerging challenges and further improve the performance of energy‐related technologies are also provided.
An Insight into the Phase Transformation of WS2 upon Fluorination
Authors: Radhakrishnan Sruthi , Das Deya , Deng Liangzi , Sudeep Parambath M. , Colas Guillaume , de los Reyes Carlos A. , Yazdi Sadegh , Chu Ching Wu , Martí Angel A. , Tiwary Chandra Sekhar , Filleter Tobin , Singh Abhishek K. , Ajayan Pulickel M.
Published: September 2018

The transformation from semiconducting to metallic phase, accompanied by a structural transition in 2D transition metal dichalcogenides has attracted the attention of the researchers worldwide. The unconventional structural transformation of fluorinated WS2 (FWS2) into the 1T phase is described. The energy difference between the two phases debugs this transition, as fluorination enhances the stability of 1T FWS2 and makes it energetically favorable at higher F concentration. Investigation of the electronic and optical nature of FWS2 is supplemented by possible band structures and bandgap calculations. Magnetic centers in the 1T phase appear in FWS2 possibly due to the introduction of defect sites. A direct consequence of the phase transition and associated increase in interlayer spacing is a change in friction behavior. Friction force microscopy is used to determine this effect of functionalization accompanied phase transformation.
Bioinspired Design of Vascular Artificial Muscle
Authors: He Qiguang , Wang Zhijian , Song Zhaoqiang , Cai Shengqiang
Published: September 2018

Recently, liquid crystal elastomers (LCEs) have drawn much attention for its wide applications as artificial muscle in soft robotics, wearable devices, and biomedical engineering. One commonly adopted way to trigger deformation of LCEs is using embedded heating elements such as resistance heating wires and photothermal particles. To enable the material to recover to its unactuated state, passive and external cooling is often employed to lower the temperature, which is typically slow and environmentally sensitive. The slow and uncontrollable recovery speed of thermally driven artificial muscle often limits its applications when even moderate cyclic actuation rate is required. In this article, inspired by biology, a vascular LCE‐based artificial muscle (VLAM) is designed and fabricated with internal fluidic channel in which the hot or cool water is injected to heat up or cool down the material to achieve fast actuation as well as recovery. It is demonstrated that the actuation stress, strain, and cyclic response rate of the VLAM are comparable to mammalian skeletal muscle. Because of the internal heating and cooling mechanism, VLAM shows a very robust actuating performance within a wide range of environmental temperatures. The VLAM designed in this article may also provide a convenient way to harvest waste heat to conduct mechanical work.
Biocatalytic Desymmetrization of Prochiral 3‐Aryl and 3‐Arylmethyl Glutaramides: Different Remote Substituent Effect on Catalytic Efficiency and Enantioselectivity
Authors: Ao Yu‐Fei , Zhang Li‐Bin , Wang Qi‐Qiang , Wang De‐Xian , Wang Mei‐Xiang
Published: September 2018

Catalyzed by an amidase‐containing Rhodococcus erythropolis AJ270 microbial whole cell catalyst in neutral phosphate buffer at 30 °C, desymmetric hydrolysis of a series of prochiral 3‐aryl and 3‐arylmethylglutaramides efficiently afforded 3‐substituted glutaric acid monoamides in up to 95% yield and >99.5% ee. Even far away from the reaction site, the substituents on the aryl still have a significant effect on the catalytic activity and enantioselectivity and different remote substituent effect was observed for the two types of substrates. The synthetic application of biocatalytic desymmetrization was demonstrated by the facile transformation of the obtained enantiopure (R)‐3‐substituted 4‐carbamoylbutanoic acid products to chiral dihydroquinolinone and δ‐lactone compounds.

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PEPDROID: Development of a Generic DREIDING‐Based Force Field for the Assessment of Peptoid Secondary Structures
Authors: Hoyas Sébastien , Lemaur Vincent , Duez Quentin , Saintmont Fabrice , Halin Emilie , De Winter Julien , Gerbaux Pascal , Cornil Jérôme
Published: September 2018

α‐Peptoids are peptido‐mimetic foldamers based on poly‐N‐substituted glycines that currently receive a growing interest due to their larger structural diversity, easier synthetic pathways, and larger thermal stability compared to peptides. An appropriate side chain appended to the nitrogen atoms is often crucial to constrain the peptoids into well‐defined and active rigid structures for applications. To shed light on the secondary structure of peptoids, accurate methods for structural characterization are mandatory and typically involve the association of circular dichroism and nuclear magnetic resonance spectroscopies. Molecular simulations can also prove highly complementary to rationalize the relationship between their primary and secondary structures, although much less studies have been reported to date compared to the knowledge accumulated on peptides. To this end, the PEPDROID force field has been developed based on the DREIDING force field, by incorporating a new set of parameters relative to (α and β) peptoids bearing different side chains. The ability of PEPDROID to assess the secondary structure of peptoids by generating Ramachandran‐like plots matching those previously obtained at a quantum‐chemical level for model systems has been demonstrated. For further sake of validation, it is demonstrated that PEPDROID can reproduce the experimental structures of either α‐ or β‐peptoids.
Photochemical Upconversion Light Emitting Diode (LED): Theory of Triplet Annihilation Enhanced by a Cavity
Authors: Frazer Laszlo
Published: September 2018

Artificial lighting is a widespread technology which consumes large amounts of energy. Triplet–triplet annihilation photochemical upconversion is a method of converting light to a higher frequency. Here, it is shown theoretically that photochemical upconversion can be applied to Watt‐scale lighting, with performance closely approaching the 50% quantum yield upper limit. The dynamic equilibrium of an efficient device consisting of an LED, an upconverting material, and an optical cavity is described from optical and thermal perspectives.
Selected properties of polycaprolactone containing natural anti‐aging compounds
Authors: Moraczewski Krzysztof , Stepczyńska Magdalena , Malinowski Rafał , Budner Bogusław , Karasiewicz Tomasz , Jagodziński Bartłomiej
Published: September 2018

Polyphenols are a group of chemical compounds that have very good anti‐aging properties. Natural plant substances may be an excellent source of polyphenols. The paper presents study on polycaprolactone containing from 0.5 to 10 wt% extracts of coffee, cocoa, or cinnamon. Preliminary investigations of anti‐aging properties of tested extracts were carried out. The selected thermal and mechanical properties have also been determined. The results indicate that tested extracts have good anti‐aging properties and do not adversely affect properties of polycaprolactone. The obtained materials had similar or even better properties than a reference sample containing a commercial anti‐aging compound.
Human body symmetry and immune efficacy in healthy adults
Authors: Pawlowski Boguslaw , Borkowska Barbara , Nowak Judyta , Augustyniak Daria , Drulis‐Kawa Zuzanna
Published: September 2018

Objectives

More symmetric organisms are perceived as more attractive. Fluctuating asymmetry (FA) i.e. small, random deviations from perfect bilateral symmetry, is supposed to inform about developmental instability. According to the good genes hypothesis, a low level of FA is a putative cue to an organism's biological quality. An important aspect of this quality is the immune system functioning. The aim of this study was to evaluate the relationship between immune system functioning and body symmetry in healthy people.

Materials and Methods

The composite body FA (cFA) was assessed on the basis of six bilateral traits (on hands and feet). The ISF was determined by many innate (total complement and lysozyme activity, neutrophils function) and adaptive immune parameters (T CD3 and B CD19 lymphocytes, total IgA and IgG and response to flu vaccine). A total of 98 men and 92 women were subjected to flu (among them 37 men and 30 women also to tetanus) vaccination. The blood samples were collected before and 4 weeks after the antigens exposure. Immunomodulatory factors: participant's age, body fat, and free testosterone level, were controlled.

Results

Apart from the weak positive association between CD3 or CD19 and cFA in men, we found no association between the level of body symmetry and the rest of the analyzed immune parameters for both sexes.

Discussion

Our results are the opposite of thegood genes hypothesisprediction and suggest that in western, healthy populations, human mate preferences for more symmetric bodies are not related to immune competence.
A Charge‐Separated State that Lives for Almost a Second at a Conductive Metal Oxide Interface
Authors: Sampaio Renato N. , Troian‐Gautier Ludovic , Meyer Gerald J.
Published: September 2018

Transparent conductive oxides (TCOs) are widely used commercially available materials for opto‐electronic applications, yet they have received very little attention for dye‐sensitization applications. Now, mesoporous thin films of conductive indium‐doped tin oxide (ITO) nanocrystallites are shown to support long‐lived charge separation with first‐order recombination kinetics (k=1.5 s−1). A layer‐by‐layer technique was utilized to spatially arrange redox and/or chromophoric molecular components on ITO. Spectroelectrochemical measurements demonstrated that upon light absorption, each component provided a free‐energy gradient to direct electron transfer at the conductive oxide interface. The long‐lived nature of the photogenerated charge separated states provide favorable conditions for photocatalytic solar fuel production. Furthermore, the first‐order recombination kinetics are most ideal for the fundamental understanding of interfacial charge separation dynamics.
Redox‐Active Reagents for Photocatalytic Generation of the OCF3 Radical and (Hetero)Aryl C−H Trifluoromethoxylation
Authors: Zheng Weijia , Lee Johnny W. , Morales‐Rivera Cristian A. , Liu Peng , Ngai Ming‐Yu
Published: September 2018

The trifluoromethoxy (OCF3) radical is of great importance in organic chemistry. Yet, the catalytic and selective generation of this radical at room temperature and pressure remains a longstanding challenge. Herein, the design and development of a redox‐active cationic reagent (1) that enables the formation of the OCF3 radical in a controllable, selective, and catalytic fashion under visible‐light photocatalytic conditions is reported. More importantly, the reagent allows catalytic, intermolecular C−H trifluoromethoxylation of a broad array of (hetero)arenes and biorelevant compounds. Experimental and computational studies suggest single electron transfer (SET) from excited photoredox catalysts to 1 resulting in exclusive liberation of the OCF3 radical. Addition of this radical to (hetero)arenes gives trifluoromethoxylated cyclohexadienyl radicals that are oxidized and deprotonated to afford the products of trifluoromethoxylation.
Mechanically Responsive Crystalline Coordination Polymers with Controllable Elasticity
Authors: Đaković Marijana , Borovina Mladen , Pisačić Mateja , Aakeröy Christer B. , Soldin Željka , Kukovec Boris‐Marko , Kodrin Ivan
Published: September 2018

Crystalline coordination polymers tend to be brittle and inelastic, however, we now describe a family of such compounds that are capable of displaying mechanical elasticity in response to external pressure. The design approach successfully targets structural features that are critical for producing the desired mechanical output. The elastic crystals all comprise 1D cadmium(II) halide polymeric chains with adjacent metal centres bridged by two halide ions resulting in the required stacking interactions and short “4 Å” crystallographic axes. These polymeric chains (structural “spines”) are further organized via hydrogen bonds and halogen bonds perpendicular to the direction of the chains. By carefully altering the strength and the geometry of these non‐covalent interactions, we have demonstrated that it is possible to control the extent of elastic bending in crystalline coordination compounds.
Observation of Carbodicarbene Ligand Redox Noninnocence in Highly Oxidized Iron Complexes
Authors: Chan Siu‐Chung , Gupta Puneet , Engelmann Xenia , Ang Zhi Zhong , Ganguly Rakesh , Bill Eckhard , Ray Kallol , Ye Shengfa , England Jason
Published: September 2018

To probe the possibility that carbodicarbenes (CDCs) are redox active ligands, all four members of the redox series [Fe(1)2]n+ (n=2–5) were synthesized, where 1 is a neutral tridentate CDC. Through a combination of spectroscopy and DFT calculations, the electronic structure of the pentacation is shown to be [FeIII(1.+)2]5+ (S=
). That of [Fe(1)2]4+ is more ambiguous, but it has significant contributions from the open‐shell singlet [FeIII(1)(1.+)]4+ (S=0). The observed spin states derive from antiferromagnetic coupling of their constituent low‐spin iron(III) centres and cation radical ligands. This marks the first time redox activity has been observed for carbones and expands the diverse chemical behaviour known for these ligands.
Cyclodextrin‐Based [3]Rotaxane‐Crosslinked Fluorescent Polymer: Synthesis and De‐Crosslinking Using Size Complementarity
Authors: Akae Yosuke , Sogawa Hiromitsu , Takata Toshikazu
Published: September 2018

Vinyl‐group‐substituted, α‐cyclodextrin‐based, size‐complementary [3]rotaxanes were synthesized as crosslinkers for rotaxane‐crosslinked poly(methyl methacrylate) (RCP) by radical polymerization. The size complementarity of the crosslinkers made it possible to de‐crosslink the RCP by heating, and the degree of decoupling was monitored by fluorescence intensity, depending on the state of the axle component of the rotaxane crosslink moiety.
Einfacher Zugang zum ersten stabilen {BH2}− Dihydroborylanion
Authors: Arrowsmith Merle , Mattock James D. , Hagspiel Stephan , Krummenacher Ivo , Vargas Alfredo , Braunschweig Holger
Published: September 2018

Während die Ein‐Elektronen‐Reduktion von (CAACMe)BH2Br (CAACMe=1‐(2,6‐Diisopropylphenyl)‐3,3,5,5‐tetramethylpyrrolidin‐2‐yliden) das Hydridumlagerungsisomer des entsprechenden Tetrahydrodiborans erzeugt, führt eine weitere, reversible Reduktion zur ersten stabilen Borylanion‐Stammverbindung, [(CAACMe)BH2]−, die als besonders starkes Bornukleophil reagiert.
Palladium Phosphide as a Stable and Efficient Electrocatalyst for Overall Water Splitting
Authors: Luo Fang , Zhang Quan , Yu Xinxin , Xiao Shenglin , Ling Ying , Hu Hao , Guo Long , Yang Zehui , Huang Liang , Cai Weiwei , Cheng Hansong
Published: September 2018

A palladium phosphide electrocatalyst supported on carbon black (PdP2@CB) shows efficient water splitting in both alkaline and neutral electrolytes. Significantly lower overpotentials are required for PdP2@CB (27.5 mV in 0.5 m H2SO4; 35.4 mV in 1 m KOH; 84.6 mV in 1 m PBS) to achieve a HER electrocatalytic current density of 10 mA cm−2 compared to commercial Pt/CB (30.1 mV in 0.5 m H2SO4; 46.6 mV in 1 m KOH; 122.7 mV in 1 m PBS). Moreover, no loss in HER activity is detectable after 5000 potential sweeps. Only 270 mV and 277 mV overpotentials are required to reach a current density of 10 mA cm−2 for PdP2@CB to catalyze OER in 1 m KOH and 1 m PBS electrolytes, which is better OER activity than the benchmark IrO2 electrocatalyst (301 mV and 313 mV to drive a current density of 10 mA cm−2). 1.59 V and 1.72 V are needed for PdP2@CB to achieve stable water splitting catalytic current density of 10 mA cm−2 in 1 m PBS and 50 mA cm−2 in 1 m KOH for 10 h, respectively.
Aerobic Solid State Red Phosphorescence from Benzobismole Monomers and Patternable Self‐Assembled Block Copolymers
Authors: Parke Sarah M. , Hupf Emanuel , Matharu Gunwant K. , de Aguiar Inara , Xu Letian , Yu Haoyang , Boone Michael P. , de Souza Gabriel L. C. , McDonald Robert , Ferguson Michael J. , He Gang , Brown Alex , Rivard Eric
Published: September 2018

The synthesis of the first bismuth‐containing macromolecules that exhibit phosphorescence in the solid state and in the presence of oxygen is reported. These red emissive high molecular weight polymers (>300 kDa) feature benzobismoles appended to a hydrocarbon scaffold, and were built via an efficient ring‐opening metathesis (ROMP) protocol. Moreover, our general procedure readily allows for the formation of cross‐linked networks and block copolymers. Attaining stable red phosphorescence with non‐toxic elements remains a challenge and, thus, our new class of soluble (processable) polymeric phosphor is of great interest. Furthermore, the formation of bismuth‐rich cores within organic–inorganic block copolymer spherical micelles is possible, leading to patterned arrays of bismuth in the film state.
Stable Face‐to‐Face Singlet Diradicaloids: Triply Linked Corrole Dimer Gallium(III) Complexes with Two μ‐Hydroxo‐Bridges
Authors: Ooi Shota , Shimizu Daiki , Furukawa Ko , Tanaka Takayuki , Osuka Atsuhiro
Published: September 2018

In known singlet diradicaloid molecules, two inherent radicals are interacted antiferromagnetically as a result of delicate energetic balances between closed‐shell and open‐shell states. Reported herein is that gallium(III) metalations of triply linked corrole dimers provide face‐to‐face dimers, with two μ‐hydroxo‐bridges, and they display curved π‐planes nearing each other at about 3.24 Å. Based on ESR and SQUID measurements, and theoretical calculations, the dimers have been assigned as singlet diradicaloids that consist of two monoradicals each delocalized on the triply linked corrole dimer planes. Therefore, it is concluded that the dimers have unusual open‐shell states stabilized by large through‐space spin‐exchange interactions.
Study on the spin states of asteroids using a simplistic shape model
Authors: Wang Y.‐B. , Xu Y. , Fan C.‐B. , Liu C.‐Z.
Published: September 2018

Photometric observation is one of the most important means to understand the fundamental properties of asteroids. As more and more photometric data are obtained, expanding effectively the number of samples on the spin states of asteroids has become an important research topic. To obtain a preliminary solution of the spin state without statistical discrepancy by the photometric observations derived from a handful of apparitions, a moderate‐complexity shape model consisting of eight adjacent octants with different semiaxes, namely cellinoid ellipsoid, can be adopted. Using this model and employing a Markov chain Monte Carlo (MCMC) method, the spin states of four asteroids are discussed based on the existing photometric data.
Untersuchungen zur Luftqualität an Verkehrswegen mit Drohnen
Authors: Baum Anja , Günther Lucas , Düring Ingo , Wehner Birgit
Published: September 2018

Drohnen, die auch als UAV/UAS (Unmanned Aerial Vehicles/Systems) oder RPAS (Remotely Piloted Aircraft Systems) bezeichnet werden, werden derzeit neben der Anwendung im privaten Umfeld für eine große Menge an kommerziellen Anwendungen diskutiert, entwickelt und eingesetzt. Die Messung von Luftqualitätsparametern mit auf Drohnen mitgeführten Kleingeräten ist in diesem Zusammenhang eine sehr junge Disziplin.

Durch die Anwendung auf Drohnen können so z. B. Kurzzeitmessungen in Höhen‐ und Längsprofilen oder anderen Messanordnungen als Ergänzung von Daten kontinuierlich arbeitender Referenzverfahren oder zur Einschätzung der besten Positionierung von festen Messstationen vor einem Aufbau durchgeführt werden.

Im Rahmen eines verkehrsträgerübergreifenden Expertennetzwerks wurde eine Machbarkeitsstudie durchgeführt, in der auf dem Markt befindliche Systeme gegenübergestellt und Empfehlungen für den Einsatz an Straßen, Wasserstraßen sowie Bahntrassen abgeleitet wurden. Mit ersten Testmessungen konnten darüber hinaus Hinweise auf die Eignung von Messsystemen gewonnen und Erfahrungen mit den Besonderheiten der Messung an Verkehrswegen gesammelt werden.
Development of a method for quantitative determination of the cytotoxic agent piplartine (piperlongumine) in multiple skin layers
Authors: Carvalho Vanessa F. M. , Giacone Daniela V. , Costa‐Lotufo Leticia V. , Silveira Edilberto Rocha , Lopes Luciana B.
Published: September 2018

This study reports the development of a simple and reproducible method, with high rates of recovery, to extract the cytotoxic agent piplartine from skin layers, and a sensitive and rapid UV‐HPLC method for its quantification. Considering the potential of piplartine for topical treatment of skin cancer, this method may find application for formulation development and pharmacokinetics studies to assess cutaneous bioavailability. Porcine skin was employed as a model for human tissue. Piplartine was extracted from the stratum corneum (SC) and remaining viable skin layers (VS) using methanol, vortex homogenization and bath sonication, and subsequently assayed by HPLC using a C18 column, and 1:1 (v/v) acetonitrile–water (adjusted to pH 4.0 with acetic acid 0.1%) as mobile phase. The quantification limit of piplartine was 0.2 μg/mL (0.6 μm), and the assay was linear up to 5 μg/mL (15.8 μm), with within‐day and between‐days assay coefficients of variation and relative errors <15%. Piplartine recovery from SC and VS varied from 86 to 96%. The method was suitable to assay samples from skin penetration studies, enabling detection of differences in cutaneous delivery in different skin compartments resulting from treatment with various formulations and time periods.
Development and validation of a hydrophilic interaction ultra‐high‐performance liquid chromatography–tandem mass spectrometry method for rapid simultaneous determination of 19 free amino acids in rat plasma and urine
Authors: Wen Yongqing , Yuan Xuemei , Qin Feng , Zhao Longshan , Xiong Zhili
Published: September 2018

Determination of amino acids in biofluids is a challenging task because of difficulties deriving from their high polarity and matrix interference. A simple, reliable and high‐throughput hydrophilic interaction UHPLC–MS/MS method was developed and validated for the rapid simultaneous determination of 19 free amino acids in rat plasma and urine samples in this paper. Hydrophilic method with a Waters Acquity UPLC BEH Amide column (100 × 2.1 mm,1.7 μm) was used with a gradient mobile phase system of acetonitrile and water both containing 0.2% formic acid. The analysis was performed on a positive electrospray ionization mass spectrometer via multiple reaction monitoring. Samples of 10 μL plasma and 50 μL urine were spiked with three deuterated internal standards, pretreated with 250 μL acetonitrile for one‐step protein precipitation and a final dilution of urine samples. Good linearities (r > 0.99) were obtained for all of the analytes with the lower limit of quantification from 0.1 to 1.2 μg/mL. The relative standard deviation of the intra‐day and inter‐day precisions were within 15.0% and the accuracy ranged from −12.8 to 12.7%. The hydrophilic interaction UHPLC–MS/MS method was rapid, accurate and high‐throughput and exhibited better chromatography behaviors than the regular RPLC methods. It was further successfully applied to detect 19 free amino acids in biological matrix.
Rescuing mesenchymal stem cell regenerative properties on hydrogel substrates post serial expansion
Authors: Rao Varsha V. , Vu Michael K. , Ma Hao , Killaars Anouk R. , Anseth Kristi S.
Published: September 2018

The use of human mesenchymal stem/stromal cells (hMSCs) in most clinical trials requires millions of cells/kg, necessitating ex vivo expansion typically on stiff substrates (tissue culture polystyrene [TCPS]), which induces osteogenesis and replicative senescence. Here, we quantified how serial expansion on TCPS influences proliferation, expression of hMSC‐specific surface markers, mechanosensing, and secretome. Results show decreased proliferation and surface marker expression after five passages (P5) and decreased mechanosensing ability and cytokine production at later passages (P11‐P12). Next, we investigated the capacity of poly(ethylene glycol) hydrogel matrices (E ~ 1 kPa) to rescue hMSC regenerative properties. Hydrogels reversed the reduction in cell surface marker expression observed at P5 on TCPS and increased secretion of cytokines for P11 hMSCs. Collectively, these results show that TCPS expansion significantly changes functional properties of hMSCs. However, some changes can be rescued by using hydrogels, suggesting that tailoring material properties could improve in vitro expansion methods.
Effects of introducing innovative teaching methods in engineering classes: A case study on classes in an Indian university
Authors: Subramanian Dhenesh Virallikattur , Kelly Patricia
Published: September 2018

Technology has been revolutionized in the past few decades and its impacts on student learning have not been fully explored. The digital divide between a student's personal technology usage and its use within the classroom remains to be bridged. This study focuses on using technology‐based innovative teaching methods with engineering classes and understanding their impact on students. The findings suggest that these learners benefited from and prefer to use innovative teaching methods backed by technology support in class. Students deprived of such innovative methods and technology would prefer to have them introduced to aid their learning experience. The study strengthens the need for decision makers in educational institutions to invest in innovative teaching methods supported by technology in order to provide a better learning platform for students, particularly in India, where engineering graduates are regarded as lacking essential skills in communication and innovation.