bluuebunny/crossref_metadata_2025 huggingface dataset:
Efficient Luminescent Solar Concentrators Based on Environmentally Friendly Cd‐Free Ternary AIS/ZnS Quantum Dots
Authors: Dhamo Lorena , Carulli Francesco , Nickl Philip , Wegner Karl David , Hodoroaba Vasile‐Dan , Würth Christian , Brovelli Sergio , Resch‐Genger Ute
Published: June 2021

Luminescent solar concentrators (LSC) allow to obtain renewable energy from building integrated photovoltaic systems. As promising efficient and long‐term stable LSC fluorophores semiconductor nanocrystals like quantum dots (QDs) with size and composition tunable optoelectronic properties have recently emerged. The most popular II/VI or IV/VI semiconductor QDs contain, however, potentially hazardous cadmium or lead ions, which is a bottleneck for commercial applications. A simple aqueous based, microwave‐assisted synthesis for environmentally friendly and highly emissive AgInS2/ZnS QDs is developed using 3‐mercaptopropionic acid (MPA) and glutathione (GSH) and their incorporation into polylaurylmethacrylate (PLMA) polymer slabs integrable in LSC devices (10.4 × 10.4 × 0.2 cm3, G = 12.98). With this simple approach, optical power efficiencies (OPE) of 3.8% and 3.6% and optical quantum efficiencies (OQE) of 24.1% and 27.4% are obtained, which are among the highest values yet reported.
Naturally Derived Organic Dyes for LED Lightings of High Color Rendering and Fidelity Index
Authors: Huang Yunping , Cohen Theodore A. , Luscombe Christine K.
Published: June 2021

Light‐emitting diodes (LEDs) are a lighting technology with a huge and ascending market. Typically, LED backlights are often paired with inorganic phosphors made from rare‐earth elements (REEs) to tune the emission lineshapes for different applications. However, REE production is a resource‐intensive process with many negative environmental impacts. Herein organic hybrid LEDs are developed using organic dyes synthesized from an abundant and non‐toxic natural product (theobromine) to replace REE phosphors. The resulted hybrid LED generates continuous emission from 400–740 nm, resulting in a high color rendering index (the current industry standard) of 90 and a color fidelity index (the most advanced and comprehensive standard) of 92, challenging commercial LEDs based on REE phosphors. In addition, the light‐converting composite is made from 99 wt% SBS, an inexpensive industrial polymer, and 1 wt% theobromine dyes, reducing the cost of the light converter to ¢1.30 for a 1 W LED, compared to approximately ¢ 19.2 of commercial products. The light converting efficiency of the dye‐SBS composite is 82%. Excited state kinetics experiments are also conducted to provide guidance to further increase the light‐converting efficiency of the theobromine dyes while maintaining excellent color rendering and fidelity.
Farmer perspectives on benefits of and barriers to extended crop rotations in Iowa, USA
Authors: Weisberger David A. , McDaniel Marshall D. , Arbuckle J. G. , Liebman Matt
Published: June 2021

The highly specialized maize (Zea mays L.) and soybean [Glycine max (L.) Merr.] production system that dominates midwestern U.S. agriculture has led to widespread on‐farm and off‐farm degradation of and damage to natural resources. The practice of extending maize–soybean rotations with small grains and forages has great potential to balance production and environmental goals, but adoption of these practices is low. Because little is known about farmers’ perspectives on extended rotations, we conducted social survey research with Iowa farmers to address this knowledge gap. Results show that farmers understand the potential benefits of extended rotations using small grains, but they perceive major barriers to use. The highest‐rated barriers were structural, such as lack of markets. Structural barriers cannot be easily addressed by individual farmers, indicating that efforts to address negative impacts of specialized commodity production through extended rotations with small grains will require transformative changes in agri‐food policies, programs, and ultimately markets.
Conductivity Modulation of 3D‐Printed Shellular Electrodes through Embedding Nanocrystalline Intermetallics into Amorphous Matrix for Ultrahigh‐Current Oxygen Evolution
Authors: Chang Shuai , Zhang Yu , Zhang Bangmin , Cao Xun , Zhang Lei , Huang Xiaolei , Lu Wanheng , Ong Chun Yee Aaron , Yuan Shuang , Li Chaojiang , Huang Yizhong , Zeng Kaiyang , Li Liqun , Yan Wentao , Ding Jun
Published: June 2021

Scaling up commercial hydrogen production by water electrolysis requires efficient oxygen evolution reaction (OER) electrodes that can deliver large current densities (more than 500 mA cm−2) at low overpotentials. Here, a highly active and conductive shell‐based cellular (Shellular) electrode is developed through a strategy of embedding nanocrystalline Ni3Nb intermetallics into an amorphous NiFe‐OOH matrix. The tailor‐made laser remelting process enables the dispersive precipitation of corrosion‐resistant nanocrystalline Ni3Nb in large numbers. After in situ electrochemical activation in the self‐developed growth‐mode‐control electrolyte, the amorphous NiFe‐OOH nanosheets and nanocrystalline Ni3Nb are formed on the as‐printed Inconel 718. The conductive atomic force microscopy (C‐AFM) studies and density functional theory (DFT) calculations elucidate that nanocrystalline Ni3Nb can simultaneously enhance the conductivity and activity of the catalyst film. Additionally, a Shellular structure inspired by nature is designed, interestingly, its specific surface area keeps constant with increases in porosity. This design can result in a large surface area and high porosity but with less material cost. Using this electrochemically activated Shellular electrode for OER, a high current density of 1500 mA cm−2 is achieved at a record‐low overpotential of 261 mV with good durability. This development may open the door for large‐scale industrial water electrolysis.
Auto‐Switching Self‐Powered System for Efficient Broad‐Band Wind Energy Harvesting Based on Dual‐Rotation Shaft Triboelectric Nanogenerator
Authors: Yong Shun , Wang Jiyu , Yang Lijun , Wang Hanqing , Luo Hao , Liao Ruijin , Wang Zhong Lin
Published: June 2021

A triboelectric nanogenerator (TENG) based self‐powered system for wind energy harvesting introduces a desirable solution to alleviate the expanding energy supply concerns in the development of the internet of things. In this work, an auto‐switching self‐powered system based on a dual‐rotation shaft TENG (D‐TENG) is reported to effectively harvest wind energy over a broad‐band wind speed (2.2–16 m s−1). The D‐TENG is designed in a concentric dual‐rotation shaft structure, in which two independent TENGs with different shapes, sizes, and arm lengths of wind cups are rationally coupled. The integration of the two TENGs with varied structural parameters achieves mutual compensation of their own merits, enabling the whole system to have preferable aerodynamics and high energy conversion efficiency over a broad range of wind speeds. Moreover, an electromagnetic generator (EMG) with the same energy collection module is also fabricated for a comparison with TENG in the start‐up properties and average output power. Furthermore, a packaged self‐powered system is demonstrated for simulated wind energy harvesting, while the charging characteristics are also discovered. The proposed TENG renders a more efficient technique for energy harvesting and greatly expands its potential in the large‐scale wind energy harvesting that can be attributed to the multi‐stage strategy.
Examining developmental plasticity in the skeletal system through a sensitive developmental windows framework
Authors: McPherson Cait B.
Published: June 2021

Developmental plasticity facilitates energetically costly but potentially fitness‐enhancing adjustments to phenotypic trajectories in response to environmental stressors, and thus may significantly impact patterns of growth, morbidity, and mortality over the life course. Ongoing research into epigenetics and developmental biology indicate that the timing of stress exposures is a key factor when assessing their impact on developmental processes. Specifically, stress experienced within sensitive developmental windows (SDWs), discrete developmental periods characterized by heightened energy requirements and rapid growth, may alter the pace and tempo of growth in ways that significantly influence phenotypic development over both the short and long term. In human skeletal biology, efforts to assess how developmental environments shape health outcomes over the life course could be enhanced by incorporating the SDW concept into existing methodological approaches. The goal of this article is to outline an interpretive framework for identifying and interpreting evidence of developmental stress in the skeletal system using the SDW concept. This framework provides guidance for the identification of elements most likely to capture evidence of stress most relevant to a study's core research questions, the interpretation of developmental stress exhibited by those elements, and the relationship of skeletal indicators of stress to the demographic patterning of morbidity and mortality. Use of the SDW concept in skeletal biology has the potential to enrich traditional approaches to addressing developmental origins of health and disease hypotheses, by targeting periods in which individuals are most susceptible to stress and thus most likely to exhibit plasticity in response.
Microarray microRNA profiling of urinary exosomes in a 5XFAD mouse model of Alzheimer’s disease
Authors: Song Zhiqi , Qu Yajin , Xu Yanfeng , Zhang Ling , Zhou Li , Han Yunlin , Zhao Wenjie , Yu Pin , Zhang Yu , Li Xianglei , Qin Chuan
Published: June 2021

Background

Alzheimer's disease (AD) is an incurable and irreversible neurodegenerative disease, without a clear pathogenesis. Therefore, identification of candidates before amyloid‐β plaque (Aβ) deposition proceeds is of major significance for earlier intervention in AD.

Methods

To explore the potential noninvasive earlier biomarkers of AD in a 5XFAD mouse model, microRNAs (miRNAs) from urinary exosomes in 1‐month‐old pre‐Aβ accumulation 5XFAD mice models and their littermate controls were profiled by microarray analysis. The differentially expressed miRNAs were further analyzed via droplet digital PCR (ddPCR).

Results

Microarray analysis demonstrated that 48 differentially expressed miRNAs (18 upregulated and 30 downregulated), of which six miRNAs – miR‐196b‐5p, miR‐339‐3p, miR‐34a‐5p, miR‐376b‐3p, miR‐677‐5p, and miR‐721 – were predicted to display gene targets and important signaling pathways closely associated with AD pathogenesis and verified by ddPCR.

Conclusions

Urinary exosomal miRNAs showing differences in expression prior to Aβ‐plaque deposition were identified. These exosomal miRNAs represent potential noninvasive biomarkers that may be used to prevent AD in clinical applications.
Simultaneous Cooling of Two Mechanical Resonators with Intracavity Squeezed Light
Authors: Liu Yu‐Mu , Cheng Jing , Wang Hong‐Fu , Yi Xuexi
Published: June 2021

A scheme is proposed to cool two mechanical resonators simultaneously to the quantum ground state, whatever sideband resolution, in an optomechanical system with χ(2) nonlinear medium, where the cavity light is squeezed. By selecting the system parameters appropriately, the influence from cavity dissipation can be completely removed and the quantum backaction heating is suppressed at the same time. It is found that the cooling performance is determined by the coupling strength and frequency detuning between two mechanical resonators. The numerical results indicate that the final phonon occupancy of the two mechanical resonators is no longer strictly limited by the sideband resolution and the cooling scheme can work well no matter in weak or strong effective optomechanical coupling regime.
A CRET‐Based Multicolor Sensing Nanoplatform for Simultaneously and Sensitively Visualizing Multiple Circulating MicroRNAs
Authors: Xu Jie , Shi Lin , Wang Han , Li Tao
Published: June 2021

Circulating microRNA (miRNAs) have been proven as potential biomarkers for disease diagnosis. Herein, this work reports the design of a chemiluminescence resonance energy transfer (CRET) based multicolor sensing nanoplatform with a portable smartphone as mini‐detector for simultaneous and sensitive analysis of multiple circulating miRNAs. Universal multicomponent nucleic acid enzyme functionalized gold nanoparticle (MNAzyme@AuNP) nanoprobes activated by the addition of different target miRNAs were constructed. As a result, spherical nucleic acid enzyme (SNAzyme) with high catalytic activity for the luminol‐H2O2 chemiluminescence or CRET reaction was produced. It enables the construction of a multicolor sensing nanoplatform for simultaneously visualizing multiple miRNAs based on chemiluminescence imaging arrays (CLIA). In this way, acute myocardial infarction (AMI) related biomarkers, miR‐133a and miR‐499, were detected with high sensitivity and selectivity in human serum.
Antibacterial self‐healing anticorrosion coatings from single capsule system
Authors: Song Yan , Chen Kaifeng , Wang Jingjing , Liu Yuan , Yang Jingzhi , Zhang Dawei , Qi Tao , Li Guo Liang
Published: June 2021

It is highly desirable to develop self‐healing anticorrosion coatings with enhanced antibacterial function to prevent the scratched area to be fouled or corroded in harsh environments. Herein, we report antibacterial self‐healing anticorrosion coatings via the simple incorporation of the easily synthesized single polymer microcapsule system. Well‐defined polymer microcapsules containing isophorone diisocyanate (IPDI) as a healing agent and 4,5‐dichloro‐2‐n‐octyl‐4‐isothiazolin‐3‐one (DCOIT) as antibacterial molecules were synthesized by one‐pot polymerization. The diameter and core fraction were around 30 μm and 90%, respectively. The active DCOIT content in the core material could be precisely controlled by adjusting the DCOIT/IPDI feeding ratio. The DCOIT/IPDI microcapsules‐embedded protective coating exhibits an adaptive self‐healing anticorrosion property, as shown by electrochemical test under the condition of the salt‐water immersion. Furthermore, the self‐healing coating showed efficient antibacterial function against Escherichia coli and Pseudomonas aeruginosa, which is due to the released active biocide molecules on the damaged surfaces. In contrast to other systems, this single capsule system without any catalyst is perspective for extending the service time of the antibacterial self‐healing materials in harsh environment.
Bi‐layer gelatin active films with “Pitanga” leaf hydroethanolic extract and/or natamycin in the second layer
Authors: Luciano Carla G. , Tessaro Larissa , Lourenço Rodrigo V. , Bittante Ana Mônica Q. B. , Fernandes Andrezza M. , Sobral Paulo J. A.
Published: June 2021

Research on biopolymers‐based active films produced with natural antioxidants and/or antimicrobials has gained attention over the last few years; however, anti‐mold activity has been less studied than those of anti‐bacteria. The aim of this work was the development and characterization of bi‐layer films based on gelatin with natamycin and/or “Pitanga” leaf hydroethanolic extract in the second thin layer in order to determine the effects of these bioactive compounds on bi‐layered film properties. The films were characterized regarding their moisture content and solubility in water, optical properties, microstructure, mechanical and thermal properties, water contact angle, water vapor permeability, UV/visible light transmission, X‐ray diffraction, Fourier transform infrared (FTIR) spectroscopy, and antioxidant and anti‐mold activities. Active films presented activity againstPenicillium sppandAspergillus nigerand demonstrated antioxidant activity, as measured by ABTS•+and DPPH•methods. Neither additive used in the films' second layer significantly affected the films' moisture content, thermal properties or the molecular interactions of the polymer matrix, assessed by FTIR, although some mechanical properties were affected, and the water contact angle. In conclusion, bi‐layer films have reduced the quantity of additives required to maintain the antioxidant and anti‐mold activities, as compared to similar monolayer films of the same thickness.
Effect of glycerol on electrical conducting of chitosan/polyaniline blends
Authors: de Oliveira Ana Carolina Salgado , Santos Taline Amorim , Ugucioni Julio Cesar , da Rocha Roney Alves , Borges Soraia Vilela
Published: June 2021

Chitosan (Cs) and polyaniline (PANI) were studied in this article for possible application as conductive and flexible films. Cs is a biodegradable polymer, that presents interesting properties as film applications. Otherwise, PANI is a semiconductor polymer with a wide range of applications. The films were produced by casting adding 30% glycerol and glutaraldehyde. The morphology, thermally, chemical structure, and electrical properties of films were obtained. Results showed the casting technique becomes possible to obtain self‐standing films, with a chemical structure identical to precursor materials. Glutaraldehyde reacted to amine groups of terminal PANI chains, acting in the increase of electric conductivity and decrease of sheet resistance. The plasticizing effect of glycerol increased the spacing between Cs chains and facilitated the PANI dispersion. Therefore, glycerol and glutaraldehyde proved to be extremely efficient in increasing the electrical conductivity of blends.
Osteology of the enigmatic threadsnake speciesEpictia unicolorandTrilepida guayaquilensis(Serpentes, Leptotyphlopidae) with generic insights
Authors: Koch Claudia , Martins Angele , Joshi Mitali , Pinto Roberta R. , Passos Paulo
Published: June 2021

Since the rearrangement of all leptotyphlopid species previously known as “Leptotyphlops” in Adalsteinsson et al. (2009)'s paper, several taxa have remained untested regarding their generic identity and have been assigned to different genera based on phenotypic data or, in some cases, without any clear justification. Most of the difficulties in assigning some leptotyphlopid taxa are due to their conserved external morphology, summed with a relatively small number of available specimens, which complicate the recognition of a unique combination of characters for their reasonable generic allocation. On the other hand, recent osteological studies—especially those on the skull—provide relevant data combinations for species assignment and even for the recognition of new genera. In this work, we have attempted to determine the generic allocation ofEpictia unicolorandTrilepida guayaquilensis—both species currently known only by their holotype—based on a detailed description of cranial and post‐cranial osteology. We confirm the assignment ofE. unicolorto the genusEpictiadespite the divergent configuration of cephalic shields. Based mainly on data from the skull, suspensorium, and cervical vertebrae but supported by external morphology as well as a redescription of the holotype, we propose the assignment ofTrilepida guayaquilensisto the genusEpictia. This study provides not only detailed data on the osteology ofEpictia, but also a first approach to the putative combination of osteological characters for the genus.
Microsequential injection analysis/lab‐on‐valve system for the automatic evaluation of acetylcholinesterase inhibitors
Authors: Ndongo Thierno Moussa , Passos Marieta L. C. , Durães Fernando , Resende Diana I. S. P. , Pinto Madalena , Sousa Emília , Saraiva Maria Lúcia M. F. S.
Published: June 2021

A miniaturized microsequential injection/lab‐on‐valve (µSIA–LOV) system was developed and shown to be a useful alternative to perform inhibitory studies on acetylcholinesterase. These studies are essential for the evaluation of the potential therapeutic effect of drugs commonly used in the treatment of Alzheimer's disease. Donepezil, galantamine, and rivastigmine were tested, in addition to compounds based on the xanthone scaffold. Four of these xanthone derivatives were identified as having EC50 values between 676 and 4466 µmol/l, showing a potential inhibitory effect higher than the clinical agent rivastigmine. The developed automatic system added advantages of reduction of reagents and sample consumption (around 55 µl per analysis), lower cost per analysis, and the generation of less waste (around 1.2 ml per analysis). The µSIA–LOV system is also a robust, rapid, reliable, and simple system to use. Docking studies suggested a possible mode of interaction with the target acetylcholinesterase protein.
A Distinct Macrophage Subset Mediating Tissue Destruction and Neovascularization in Giant Cell Arteritis: Implication of the YKL‐40/Interleukin‐13 Receptor α2 Axis
Authors: van Sleen Yannick , Jiemy William F. , Pringle Sarah , van der Geest Kornelis S. M. , Abdulahad Wayel H. , Sandovici Maria , Brouwer Elisabeth , Heeringa Peter , Boots Annemieke M. H.
Published: June 2021

Objective

Macrophages mediate inflammation, angiogenesis, and tissue destruction in giant cell arteritis (GCA). Serum levels of the macrophage‐associated protein YKL‐40 (chitinase 3–like protein 1), previously linked to angiogenesis and tissue remodeling, remain elevated in GCA despite glucocorticoid treatment. This study was undertaken to investigate the contribution of YKL‐40 to vasculopathy in GCA.

Methods

Immunohistochemistry was performed on GCA temporal artery biopsy specimens (n = 12) and aortas (n = 10) for detection of YKL‐40, its receptor interleukin‐13 receptor α2 (IL‐13Rα2), macrophage markers PU.1 and CD206, and the tissue‐destructive protein matrix metalloproteinase 9 (MMP‐9). Ten noninflamed temporal artery biopsy specimens served as controls. In vitro experiments with granulocyte–macrophage colony‐stimulating factor (GM‐CSF)– or macrophage colony‐stimulating factor (M‐CSF)–skewed monocyte‐derived macrophages were conducted to study the dynamics of YKL‐40 production. Next, small interfering RNA–mediated knockdown of YKL‐40 in GM‐CSF–skewed macrophages was performed to study its effect on MMP‐9 production. Finally, the angiogenic potential of YKL‐40 was investigated by tube formation experiments using human microvascular endothelial cells (HMVECs).

Results

YKL‐40 was abundantly expressed by a CD206+MMP‐9+ macrophage subset in inflamed temporal arteries and aortas. GM‐CSF–skewed macrophages from GCA patients, but not healthy controls, released significantly higher levels of YKL‐40 compared to M‐CSF–skewed macrophages (P = 0.039). In inflamed temporal arteries, IL‐13Rα2 was expressed by macrophages and endothelial cells. Functionally, knockdown of YKL‐40 led to a 10–50% reduction in MMP‐9 production by macrophages, whereas exposure of HMVECS to YKL‐40 led to significantly increased tube formation.

Conclusion

In GCA, a GM‐CSF–skewed, CD206+MMP‐9+ macrophage subset expresses high levels of YKL‐40 which may stimulate tissue destruction and angiogenesis through IL‐13Rα2 signaling. Targeting YKL‐40 or GM‐CSF may inhibit macrophages that are currently insufficiently suppressed by glucocorticoids.
Kinetics of Oxidative Cracking of n‐Hexane to Light Olefins using Lattice Oxygen of a VOx/SrO‐γAl2O3 Catalyst
Authors: Amusa Hussein K. , Adamu Sagir , Arjah Abeer S. , Al‐Bogami Saad A. , Al‐Ghamdi Sameer , Razzak Shaikh A. , Hossain Mohammad M.
Published: June 2021

The kinetics of oxidative cracking of n‐hexane to light olefins using the lattice oxygen of VOx/SrO‐γAl2O3 catalysts has been investigated. Kinetic experiments were conducted in a CREC Riser Simulator (CERC: Chemical Reactor Engineering Center), which mimics fluidized bed reactors. The catalyst's performance is partly attributed to the moderate interaction between active VOx species and the SrO‐γAl2O3 support. This moderate interaction serves to control the release of lattice oxygen to curtail deep oxidation. The incorporation of basic SrO component in the support also helped to moderate the catalyst's acidity to checkmate excessive cracking. Langmuir‐Hinshelwood model was applied to formulate the rate equations. The intrinsic kinetic parameters were obtained by fitting the experimental data to the kinetic model using a nonlinear regression algorithm at a 95% confidence interval, implemented in MATLAB. n‐Hexane transforms to olefins at a specific reaction rate of 1.33 mol/gcat.s and activation energy of 119.2 kJ/mol. These values when compared with other duplets (i. e., ki° and EA) for paraffins to olefins, show that indeed olefins are stable products of the oxidative conversion of n‐hexane over VOx/SrO‐γAl2O3 under a fluidized bed condition. Values of activation energy for all COx formation routes indicate that intermediate paraffins are likely to be cracked to form CH4 than to be converted directly to COx. On the other hand, olefins may transform partly, and directly to COx (E9=9.65 kJ/mol) than to form CH4 (E8=89.1 kJ/mol) in the presence of excess lattice oxygen. Overall, olefins appear to be stable to deep oxidation due to the role of SrO in controlling the amount of lattice oxygen of the catalyst at the reaction temperature.
Supported Palladium‐Catalyzed Carbonylative Synthesis of Diaryl Ketones from Aryl Bromides and Arylboronic Acids
Authors: Xu Tiefeng , Wang Qi , Yang Zeyi , Yi Lili , Wang Jian‐Shu , Lu Wangyang , Ying Jun , Wu Xiao‐Feng
Published: June 2021

A palladium supported on graphitic carbon nitride (Pd/g‐C3N4) catalyzed carbonylative reaction of aryl bromides and arylboronic acids by has been developed for the construction of diaryl ketones. Using benzene‐1,3,5‐triyl triformate (TFBen) as the CO source, the reaction proceeded well to give various diaryl ketones in moderate to good yields.
Standardkonforme Modellierung der geregelten natürlichen Lüftung in Simulationsprogrammen mit adaptiven Zeitschritt‐Lösern
Authors: Nicolai Andreas , Fechner Heiko
Published: June 2021

Natürliche Belüftung kann zur Aufrechterhaltung des thermischen Komforts während der Sommerperioden beitragen. In Simulationsmodellen für die Analyse des thermischen Komforts wird das mit der natürlichen Belüftung verbundene Bewohnerverhalten häufig durch die Definition von Belüftungsregelsätzen einbezogen. Beispielsweise werden Fenster geöffnet, wenn die Raumtemperatur einen vorgegebenen Grenzwert überschreitet, während gleichzeitig die Außentemperaturen unter einem Schwellenwert bleiben. Solche Regeln sind in Bauvorschriften, wie z. B. DIN 4108‐2, enthalten. Diese Regeln wurden bislang jedoch im Hinblick auf Simulationsprogramme mit Integrationsmethoden mit fester Schrittzeit festgelegt, wobei oft stündliche Schrittweiten verwendet werden. Es ist jedoch allgemein nicht möglich, diese Regeln direkt in numerische Lösungsverfahren mit fehlergesteuerter adaptiver Zeitschrittanpassung (z. B. in THERAKLES, DELPHIN, COMSOL, MODELICA‐Lösern etc.) zu übernehmen. Der Artikel erörtert Strategien und Modellvarianten, die mit solchen modernen Integrationsverfahren arbeiten und diskutiert neue Modellparameter, wie die Verzögerung oder die Totbandregelung. Die Auswirkungen dieser Parameterwahl werden anhand von Sensitivitätsstudien unter Verwendung des thermischen Raummodells THERAKLES veranschaulicht.
Normatives vs. realistisches Lüftungsverhalten
Authors: Hartner Marco , Carrigan Svenja , Kornadt Oliver , Lachmann Moritz
Published: June 2021

Das Nutzerverhalten kann eine große Diskrepanz zwischen errechnetem Energiebedarf und tatsächlichem Energieverbrauch von Gebäuden bewirken. Dabei hat sich im Rahmen eines von der Forschungsinitiative Zukunft Bau geförderten Projekts die Raumsolltemperatur als größter Einflussfaktor herausgestellt. Aufbauend auf diesen Ergebnissen wurde hier untersucht, welchen Einfluss unterschiedliche Lüftungsstrategien auf den Energiebedarf haben. Hierzu wurden für ein Untersuchungsobjekt unterschiedliche Lüftungsprofile, welche unterschiedliche Anwesenheitszeiten im Gebäude widerspiegeln, bei stundenveränderlichen Außenklimabedingungen in einem thermischen Gebäudesimulationsprogramm nachgebildet und mit den Norm‐konformen Berechnungen verglichen. Es hat sich gezeigt, dass sich durch die Stoßlüftung, im Vergleich zur normativ angenommenen dauerhaften Lüftung, eine erhebliche Einsparung der Nutzwärmeenergie ergibt, die Anzahl der Lüftungsvorgänge aber eine untergeordnete Rolle spielt. Der Vergleich mit den Messungen des Energieverbrauchs im Gebäude zeigt, dass die Nutzungsprofile mit realistischem Lüftungsverhalten hierzu eine deutlich kleinere Diskrepanz als das Norm‐konforme Nutzungsprofil aufweisen.
Using primary teeth and archived dried spots for exposomic studies in children: Exploring new paths in the environmental epidemiology of pediatric cancer
Authors: Lupo Philip J. , Petrick Lauren M. , Hoang Thanh T. , Janitz Amanda E. , Marcotte Erin L. , Schraw Jeremy M. , Arora Manish , Scheurer Michael E.
Published: June 2021

It is estimated that 300,000 children 0–14 years of age are diagnosed with cancer worldwide each year. While the absolute risk of cancer in children is low, it is the leading cause of death due to disease in children in high‐income countries. In spite of this, the etiologies of pediatric cancer are largely unknown. Environmental exposures have long been thought to play an etiologic role. However, to date, there are few well‐established environmental risk factors for pediatric malignancies, likely due to technical barriers in collecting biological samples prospectively in pediatric populations for direct measurements. In this review, we propose the use of novel or underutilized biospecimens (dried blood spots and teeth) and molecular approaches for exposure assessment (epigenetics, metabolomics, and somatic mutational profiles). Future epidemiologic studies of pediatric cancer should incorporate novel exposure assessment methodologies, data on molecular features of tumors, and a more complete assessment of gene‐environment interactions.
alpha‐Tocopherol supplementation reduces inflammation and apoptosis in high cholesterol mediated nonalcoholic steatohepatitis
Authors: Demirel‐Yalciner Tugce , Sozen Erdi , Ozaltin Esra , Sahin Ali , Ozer Nesrin Kartal
Published: June 2021

Inflammation and apoptosis signaling are crucial steps in the progression from nonalcoholic fatty liver disease (NAFLD) to nonalcoholic steatohepatitis (NASH). Alpha‐tocopherol, the most active form of vitamin E, is an important modulator of signaling mechanisms, but its involvement to cholesterol‐induced NASH pathogenesis remains poorly defined. Herein we have reported a novel effect of α‐tocopherol in the transition from hepatic steatosis to NASH. High cholesterol diet alone (without α‐tocopherol) in rabbits elevated NASH development as indicated by increased inflammatory response, apoptotic activity and liver fibrosis. Such elevation results from induction of signaling mechanisms since the expressions of IL1β, phospho c‐Jun/c‐Jun ratio, JNK, caspase 9, CHOP and Bax were increased, and recruitment of macrophage, α‐smooth muscle actin (α‐SMA) and COL1A1 into the liver tissue were induced. Alpha‐tocopherol supplementation inhibited inflammatory response, apoptosis and fibrosis development without affecting lipid accumulation in high cholesterol‐induced NASH. Specifically, α‐tocopherol lowered the inflammatory level as observed by reduced macrophage infiltration and JNK/c‐Jun signaling. Lower inflammatory status co‐occurred with the reduction of CHOP and Bax expressions as well as fibrosis‐related COL1A1 and α‐SMA levels. Taken together, α‐tocopherol supplementation inhibits cholesterol‐induced NASH development by lowering JNK/c‐Jun/inflammation axis in addition to JNK/CHOP/apoptosis signaling, which might contribute to resistance against NAFLD/NASH transition.
Pyrrolidinyl peptide nucleic acids bearing hydroxy‐modified cyclobutane building blocks: Synthesis and binding properties
Authors: Ditmangklo Boonsong , Sittiwong Wantanee , Boddaert Thomas , Vilaivan Tirayut , Aitken David J.
Published: June 2021

The conformationally constrained pyrrolidinyl PNA with a dipeptide consisting of an alternating nucleobase‐modified D‐proline and a cyclic β‐amino acid “spacer” exhibited improved nucleic acid binding properties compared to the original PNA. The pyrrolidinyl PNA with the four‐membered ring spacer (1S,2S)‐2‐aminocyclobutanecarboxylic acid (acbcPNA) are among the best performed members of the pyrrolidinyl PNA family. However, these PNA suffer some limitations such as aqueous solubility and non‐specific interactions due to their extreme hydrophobicity. In the present work, a hydroxy group is introduced onto the cyclobutane ring spacer of the acbcPNA with the aim of decreasing its hydrophobicity. To this end, a Fmoc/tBu ether‐protected 4‐hydroxy‐2‐aminocyclobutanecarboxylic acid building block was synthesized and resolved by chiral HPLC. Each enantiomer was used to synthesize the hydroxy‐modified acbcPNA employing Fmoc solid‐phase peptide synthesis. DNA/RNA binding studies indicated that the introduction of the hydroxy group to the acbcPNA decreases the binding affinity toward complementary DNA and RNA while maintaining the sequence and directional specificity of unmodified acbcPNA. The hydrophobicity of the hydroxy‐modified acbcPNA decreased with the number of hydroxy groups added as indicated by the decrease in the logP values. Only two modifications were sufficient to decrease the logP by an order of magnitude without excessively lowering the binding affinity nor the specificity. This work thus demonstrated that the specific structural modifications for this type of PNA model can be performed in a modular fashion, which paves the way toward the future realization of improving hydrophilicity and nucleic acid binding affinity as well as specificity.
Isorhapontigenin ameliorates cerebral ischemia/reperfusion injury via modulating Kinase Cε/Nrf2/HO‐1 signaling pathway
Authors: Xue Zhe , Zhao Kai , Sun Zhenghui , Wu Chen , Yu Bowen , Kong Dongsheng , Xu Bainan
Published: June 2021

Background

Isorhapontigenin (ISO) has been shown to have antioxidant activity. This study aimed to investigate the antioxidant effects of ISO on cerebral ischemia/reperfusion (I/R) injury and its possible molecular mechanisms.

Methods

Focal cerebral ischemia‐reperfusion injury (MCAO/R) model and primary cortical neurons were established an oxygen‐glucose deprivation (OGD / R) injury model. After 24 hr of reperfusion, the neurological deficits of the rats were analyzed and HE staining was performed, and the infarct volume was calculated by TTC staining. In addition, the reactive oxygen species (ROS) in rat brain tissue, the content of 4‐Hydroxynonenal (4‐HNE), and 8‐hydroxy2deoxyguanosine (8‐OHdG) were detected. Neuronal cell viability was determined by MTT assay. Western blot analysis was determined for protein expression.

Results

ISO treatment significantly improved neurological scores, reduced infarct volume, necrotic neurons, ROS production, 4‐HNE, and 8‐OHdG levels. At the same time, ISO significantly increased the expression of Nrf2 and HO‐1. The neuroprotective effects of ISO can be eliminated by knocking down Nrf2 and HO‐1. In addition, knockdown of the PKCε blocked ISO‐induced nuclear Nfr2, HO‐1 expression.

Conclusion

ISO protected against oxidative damage induced by brain I/R, and its neuroprotective mechanism may be related to the PKCε/Nrf2/HO‐1 pathway.
Resting‐state functional connectivity in patients with a complex PTSD or complex dissociative disorder before and after inpatient trauma treatment
Authors: Schlumpf Yolanda R. , Nijenhuis Ellert R. S. , Klein Carina , Jäncke Lutz , Bachmann Silke
Published: June 2021

Introduction

Recent research suggests that traumatized patients are characterized by disrupted resting‐state functional connectivity. We examined whether neural networks involved in resting‐state change over the course of a phase‐oriented inpatient treatment for complex traumatized and dissociative disorder patients. We also investigated associations between these network alterations and clinical symptoms and emotion regulation skills.

Methods

Pre‐ and post‐treatment, electroencephalography (EEG) was recorded during resting‐state in patients (n = 23) with a complex dissociative disorder (CDD) or complex posttraumatic stress disorder (cPTSD). Patients also completed clinical and emotion regulation questionnaires. To reduce variance in the collected data, patients were exclusively tested as one prototypical dissociative part referred to as Apparently Normal Part (ANP). Functional network connectivity was examined and compared with a matched healthy control group (n = 37), also measured twice.

Results

Prior to treatment and compared with controls, patients had a significantly lower functional connectivity strength within eyes‐open and eyes‐closed resting‐state networks in the theta and alpha frequency band. Following treatment, functional connectivity strength within these networks was comparable to the control group and comprised areas belonging to the default mode network (DMN) and prefrontal as well as anterior cingulate control regions. Treatment‐related network normalizations in the theta frequency band were associated with a self‐reported increase in the use of cognitive reappraisal strategies and reduction in emotion regulation difficulties.

Conclusion

Phase‐oriented trauma treatment can strengthen resting‐state network connectivity and can increase the capacity of complex traumatized and dissociative patients as ANP to handle emotional challenges effectively.
A qualitative analysis of factors influencing antiretroviral adherence among persons living with HIV in Ghana
Authors: Abdulai Martha Ali , Mevissen Fraukje E. F. , Ruiter Robert A. C. , Owusu‐Agyei Seth , Asante Kwaku Poku , Bos Arjan E. R.
Published: June 2021

Adherence to antiretroviral therapy (ART) remains an important factor in HIV prevention and treatment efforts. We explored the individual and environmental factors influencing antiretroviral adherence among PLWH in Ghana. This study used 20 semi‐structured in‐depth interviews and three focus group discussions (FGD) involving 29 PLWH attending one of three antiretroviral clinics. Thematic analysis covered experiences of PLWH clinic visits, knowledge, attitudes, self‐efficacy related to ART adherence, psychological wellbeing and stigma. The findings suggest that both individual and environmental factors including treatment outcome, coping skills, disclosure, self‐regulation, healthcare‐provider interaction, family and partner support, organization of ART clinics, stigma, and transportation cost influenced treatment adherence. Interventions that empower PLWH and reduce HIV‐related stigma in the community will most likely support antiretroviral adherence. Please refer to the Supplementary Material section to find this article's Community and Social Impact Statement.
The continuing promise of the radial access for coronary interventions
Authors: Rahman Faisal , Jneid Hani
Published: June 2021

Key Points

The radial artery access for coronary angiography and percutaneous coronary intervention is associated with reduced bleeding, vascular complications, and all‐cause mortality compared with the femoral artery access.

The radial artery access is not associated with a higher risk of stroke or myocardial infarction.

The consistent use of the radial approach and intravascular imaging‐guidance for femoral access, when needed, are likely to continue to reduce the risk of complications in the cardiac catheterization laboratory.
Editorial Comments for: “Transcatheter valve‐in‐valve implantation versus surgical redo aortic root replacement in patients with degenerated freestyle aortic bioprosthesis”
Authors: Costello Briana T. , Krajcer Zvonimir
Published: June 2021

Key Points

Valve‐in‐valve (ViV) TAVR continues to gain clinical utility across the spectrum of bioprosthesis failure.

Outcomes of ViV TAVR have repeatedly proved to be acceptable, especially in in patients with higher STS scores.

Ongoing outcome evaluation of ViV TAVR will identify which surgical prostheses, as well as which patient risk profiles, are best suited for ViV TAVR. Procedural technique and prosthesis choices can be tailored pending ongoing research.
Post‐dilation in ST‐elevation MI patients makes sense anatomically, but does it improve physiology?
Authors: Kern Morton J. , Seto Arnold H.
Published: June 2021

Key Points

High pressure post‐dilatation (PD) increases stent area which should reduce restenosis and malapposition rates.

This study indicates that PD in STEMI patients increases stent area, increases FFR, but decreases IMR in only 50% of patients with a net neutral effect on IMR and coronary flow reserve.

Future studies may identify which patients are likely to have improved microvascular physiology from PD.
Career‐Related Parental Support, Vocational Identity, and Career Adaptability: Interrelationships and Gender Differences
Authors: Zhang Jiahong , Yuen Mantak , Chen Gaowei
Published: June 2021

We examined relationships among career‐related parental support, vocational identity, and career adaptability in a sample of 1,163 Chinese technical college students. Structural equation modeling of the relationship between career‐related parental support and students' career adaptability revealed positive mediation effects of three types of vocational identity (career commitment making, identification with career commitment, and in‐depth career exploration). In contrast, career self‐doubt exhibited a negative mediation effect. Multigroup structural equation modeling showed that there were stronger relationships in male‐identified students than in female‐identified students between career‐related parental support and career commitment and career exploration. Among male‐identified students, in contrast to female‐identified students, there was a significant and negative association between career self‐doubt and concern, and there was a positive association between in‐depth career exploration and concern. These results have implications for supporting parents in facilitating children's career adaptability. Future research could identify the differential effects of paternal and maternal support on career adaptability.
Electrochemical Immunomagnetic Ochratoxin A Sensing: Steps Forward in the Application of 3,3’,5,5’‐Tetramethylbenzidine in Amperometric Assays
Authors: Höfs Soraya , Hülagü Deniz , Bennet Francesca , Carl Peter , Flemig Sabine , Schmid Thomas , Schenk Jörg A. , Hodoroaba Vasile‐Dan , Schneider Rudolf J.
Published: June 2021

Electrochemical methods offer great promise in meeting the demand for user‐friendly on‐site devices for monitoring important parameters. The food industry often runs own lab procedures, for example, for mycotoxin analysis, but it is a major goal to simplify analysis, linking analytical methods with smart technologies. Enzyme‐linked immunosorbent assays, with photometric detection of 3,3’,5,5’‐tetramethylbenzidine (TMB), form a good basis for sensitive detection. To provide a straightforward approach for the miniaturization of the detection step, we have studied the pitfalls of the electrochemical TMB detection. By cyclic voltammetry it was found that the TMB electrochemistry is strongly dependent on the pH and the electrode material. A stable electrode response to TMB could be achieved at pH 1 on gold electrodes. We created a smartphone‐based, electrochemical, immunomagnetic assay for the detection of ochratoxin A in real samples, providing a solid basis for sensing of further analytes.
Nonpolar Solvent‐based Electrolytes with a Quasi‐Solid‐State Redox Reaction for Lithium‐Sulfur Batteries
Authors: Yang Hong Sun , Kim Dong‐Min , Kim Youngjin , Lee Young Joo , Lee Kyu Tae
Published: June 2021

Li−S batteries are one of the most promising next‐generation batteries because of their high theoretical energy density and abundance of active material sulfur reducing the cost. However, conventional ether‐based electrolytes suffer from active material loss due to side reactions between dissolved polysulfides and Li metal anode, and consequential shuttle phenomenon. Herein, a promising concept of nonpolar solvent‐based electrolytes consisting of nonpolar solvent of 1,4‐difluorobenzene, lithium bis(trifluoromethanesulfonyl)imide (LiTFSI) salt, and chelating agent for Li+ cations, such as 15‐crown‐5 or 1,3‐dioxolane, is introduced to suppress the dissolution of polar polysulfides. Nonpolar electrolytes show a distinctive reaction mechanism that involved a quasi‐solid‐state redox reaction, compared to conventional ether‐based electrolytes. The discharge and charge process of nonpolar electrolytes include phase transitions with sparingly soluble and insoluble polysulfides. As a result, nonpolar solvent‐based electrolytes show excellent electrochemical performance, such as stable capacity retention and Coulombic efficiency of 93.1 % after 100 cycles at 30 °C.
Nitrogen and Phosphate Co‐doped Graphene as Efficient Bifunctional Electrocatalysts by Precursor Modulation Strategy for Oxygen Reduction and Evolution Reactions
Authors: Zhang Xiaoran , Zhang Xiao , Xiang Xue , Pan Can , Meng Qinghao , Hao Chao , Qun Tian Zhi , Kang Shen Pei , Ping Jiang San
Published: June 2021

Heteroatoms doped carbon‐based metal‐free catalysts are important candidates as alternatives for precious group metal (PGM) catalysts for oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) – two of the most important reactions in electrochemical energy conversion and storage areas. Despite the significant efforts in developing heteroatoms doped metal‐free electrocatalysts with enhanced electrocatalytic activity, few studies focus on their bifunctional activities for ORR and OER due to the unclear catalytic mechanism and complicated active sites configurations. Herein, a series of nitrogen and phosphate co‐doped carbon‐based catalysts (NP/C) are successfully synthesized via a precursor modulation strategy. In this method, 5‐aminouracil, 2, 6‐diaminopyridine and 1, 3‐diaminobenzene are selected to modulate pyridinic N (NP), graphitic N (NG) and pyrrolic N (NPY) sites, respectively, while phytic acid is used as P sites. The results demonstrate that the N and P co‐doped graphene with NP+NG+P configuration shows increased ORR performance, and on the other hand, the NP+NPY+P configuration enhances OER. Density functional theory (DFT) calculation demonstrates that different NP configurations formed by precursor modulation induce different electronic structure on surrounding carbon atoms, providing a possibility to manipulate intermediates energy in reaction pathway for ORR and OER. This study sheds new light on revealing the intrinsic correlation between active site configurations and catalytic bifunctional activity and selectivity of graphene based electrocatalysts for oxygen redox reactions.
Nothing About Us Without Us – Towards Genuine Inclusion of Disabled Scientists and Science Students Post Pandemic
Authors: Sarju Julia P.
Published: June 2021

Scientists and students with disabilities have been severely affected by the COVID‐19 pandemic, and this must be urgently addressed to avoid further entrenching existing inequalities. The need for rapid decision‐making, often by senior colleagues without lived experience of disabilities, can lead to policies which discriminate against scientists with disabilities.

This article reflects on disability declaration statistics and research in critical disability studies and social science to explore the challenges experienced by disabled scientists before and during the COVID‐19 pandemic and highlights recommendations and examples of good practice to adopt in order to challenge ableism in STEM communities and workplaces. It is vital that disabled staff and students are fully involved in decision making. This is particularly important as we continue to respond to the challenges and opportunities associated with the ongoing COVID‐19 pandemic and plan for a post‐COVID‐19 future.

This time of great change can be used as an opportunity to listen, learn, and improve working conditions and access for scientists with disabilities, and by doing so, for everyone.