bluuebunny/crossref_metadata_2025_split huggingface dataset:
A Self‐Assembled Palladium(II) Barrel for Binding of Fullerenes and Photosensitization Ability of the Fullerene‐Encapsulated Barrel
Authors: Purba Prioti Choudhury , Maity Manoranjan , Bhattacharyya Soumalya , Mukherjee Partha Sarathi 
Published: April 2021

AbstractFullerene extracts obtained from fullerene soot lack their real application due to their poor solubility in common solvents and difficulty in purification. Encapsulation of these extracts in a suitable host is an important approach to address these issues. We present a new Pd6 barrel (1), which is composed of three 1,4‐dihydropyrrolo[3,2‐b]pyrrole panels, clipped through six cis‐PdII acceptors. Large open windows and cavity make it an efficient host for a large guest. Favorable interactions between the ligand and fullerene (C60 and C70) allows the barrel to encapsulate fullerene efficiently. Thorough investigation reveals that barrel 1 has a stronger binding affinity towards C70 over C60, resulting in the predominant extraction of C70 from a mixture of the two. Finally, the fullerene encapsulated barrels C60⊂1 and C70⊂1 were found to be efficient for visible‐light‐induced singlet oxygen generation. Such preferential binding of C70 and photosensitizing ability of C60⊂1 and C70⊂1 are noteworthy.
Optimization of 3D printing parameters for high‐performance biodegradable materials
Authors: Lyu Yang , Zhao Haotian , Wen Xinlong , Lin Leyu , Schlarb Alois K. , Shi Xinyan 
Published: April 2021

AbstractDeveloping 3D printing high‐performance biodegradable materials is important to protect the environment and deal with emergencies such as COVID‐19. Fused deposition modeling (FDM), one of the 3D printing methods, has many advantages, such as low cost and wide range of materials. However, the weak interlayer adhesion is an important factor restricting the development of FDM. In addition to the influence of material properties, the optimization of 3D printing parameters is also an important means to give full play to the inherent properties of materials. The optimal 3D printing parameters are conducive to the diffusion and entanglement of molecular chains between adjacent layers. PLA/PBAT/PLA‐g‐GMA (70/30/10 wt%, PLA‐g‐GMA was a compatibilizer synthesized in our lab) was used as the research object. This work aims to analyze the mechanical properties response of biodegradable polymers products manufactured through FDM. Herein, the effect of 3D printing parameters including layer thickness, nozzle temperature, printing speed and platform temperature have been systematically investigated by orthogonal experimental design. The result showed that the excellent performance of 3D printing specimen was obtained when the layer thickness was 0.15 mm, the printing speed was 50 mm·s−1, the nozzle temperature was 200°C and the platform temperature was 50°C. The SEM images showed that the optimal 3D printing products had the best interlayer adhesion and the lowest porosity. Undergoing optimization of 3D printing processing, the yield strength and elongation at break of specimen increased by 115% and 229%, respectively. In this paper, the interlayer adhesion and mechanical properties of 3D printing products can be significantly improved by simply optimizing the 3D printing parameters without complex material modification. This work provided a new method for improving the interlayer adhesion of FDM and the mechanical properties of FDM products.
Preparation and characterization of triangular hollow porous polyacrylonitrile fiber made by coaxial wet spinning
Authors: Wang Huiyun , Wang Ping , Zhang Yan , Hu Dongmei 
Published: April 2021

AbstractHollow porous fiber with both hollow and mesoporous structural characteristics can play an important role in storage, adsorption, and other fields. Triangular hollow porous fiber was prepared by coaxial wet spinning in this paper. Polyacrylonitrile (PAN) and N‐N dimethylformamide (DMF) were blended to get cortical solution. Polyvinylpyrrolidone (PVP) and DMF were blended to get core solution. Subsequently, coaxial triangular spinneret was adopted to inject solution into coagulation bath for double diffusion and obtain primary fiber. Then PAN‐based triangular fiber with high porosity was prepared after washing and drying. Scanning electron microscopy, nitrogen physical adsorption instrument, thermogravimetric analyzer, and other instruments were used to test and characterize. The results show that the cross‐section of the fiber is triangular and has a sense of luster. The hollow degree of the fiber is as high as 84.17%, and the sheath has three‐level structure with multi‐scale pore diameters, including micropores (200 μm), submicron pores (200 nm), and nanopores (20 nm). Through the range analysis of orthogonal experiment, it is found that the concentration of cortical solution is the main factor affecting the fiber tensile strength. When the concentration of cortical solution is 17%, the concentration of core solution is 10%, the flow rate ratio of cortical solution to core solution is 10:1, and the concentration of coagulation bath is 10%, the fiber tensile strength reaches 1.43 N/mm2. The thermal insulation performance of fiber is better than that of silk, cotton and polyester. The results in this paper will provide an experimental foundation for the design and application of hollow porous profiled fibers.
Human organ phantoms for catheterization using the radiation crosslinking technique
Authors: Imanishi Ayaka , Kimura Atsushi , Miyamoto Hisao , Hiroki Akihiro , Nagasawa Naotsugu , Yoshii Fumio , Taguchi Mitsumasa 
Published: April 2021

AbstractAn artificial organ based on polyvinyl alcohol (PVA) hydrogel was developed to train medical staff to improve their ablation therapy skills, by using the radiation cross‐linking technique. The aqueous PVA solution was irradiated with γ‐rays or electron beams to produce a highly transparent, high‐strength, and flexible crosslinked hydrogel without using a crosslinking agent. Physical properties of the hydrogel, such as, gel fraction, swelling, and elastic modulus, were controlled by changing the radiation dose. The catheter ablation region on the surface of the cardiac phantom produced from PVA hydrogel with temperature‐responsive pigment inks can be visually identified by the color change. The tumor organ phantom consists of the PVA hydrogel with the purple pigment ink (healthy organ site) and red PVA hydrogel with cellulose (the tumor sites) was developed by applying this radiation crosslinking technique. The positions of the tumor hydrogel and the ablation electrode needle can be confirmed through ultrasound echography. It is possible to practice ablation on the tumor site while observing the echo images under conditions similar to the actual treatment. These novel human organ phantoms are created as a means for ablation training for treating cardiac arrhythmia and liver cancer using the radiation crosslinking technology.
Zika virus outbreak in Brazil—Lessons learned and perspectives for a safe and effective vaccine
Authors: Sáfadi Marco Aurélio Palazzi , Almeida Flavia J. , de Ávila Kfouri Renato 
Published: April 2021

AbstractZika virus (ZIKV) is an emerging pathogen of public health concern, associated with a dramatic burden in places where the virus caused outbreaks between 2015 and 2017. In the Americas, the ZIKV was first reported in Brazil and rapidly spread through the Americas. Since its first report, a number of studies have been published as we continue to learn, not only about modes of transmission, but also clinical manifestations, risk of congenital anomalies, including microcephaly and neurological malformations in fetuses born from mothers infected during pregnancy. Interventions to reduce the burden of ZIKV infection are restricted to mosquito control, and for Aedes spp mosquitoes the strategies implemented to that end proved to be unsuccessful so far. Hence the lessons we can learn following the ZIKV epidemics become of paramount importance in the development of drug treatments and in search for a vaccine.
Temperaturinduktion in Betontragwerke
Authors: Clauß Felix , Löschmann Jens , Ahrens Mark Alexander , Mark Peter 
Published: April 2021

AbstractDas Enteisen von Brückenfahrbahnen, die gesteuerte Erhärtung von Beton oder die Tragwerksverstärkung bei Temperierung sind Anwendungen für eine gezielte Temperaturinduktion in Betontragwerke. Der Beitrag behandelt dazu grundlegende Methoden. Dies sind das Erwärmen mit Infrarotstrahlern, Wärmematten oder erhitztem Wasser und das Kühlen mit Peltier‐Elementen, Kühlflüssigkeiten oder Trockeneis. Diskutiert werden die nominellen elektrischen Leistungen, die Fixierung am Bauteil, Interaktionen zwischen Temperierung und Bauteil, die Temperaturregelung und mögliche Verluste. Die Verfahren werden mit ihren Eigenschaften vorgestellt und bewertet. Als Basis dient eine Versuchsserie an Balken mit Einhausung durch Wärmedämmung. Die einzelnen Temperierverfahren werden separat untersucht und zur Erzeugung eines Temperaturgradienten kombiniert. Es zeigt sich, dass besonders Wärmematten oder Infrarotstrahler für das Heizen und die Peltier‐Kühlungen bzw. Kühlwasser für das Kühlen geeignet sind. Für die praktische Anwendung werden Empfehlungen abgeleitet.
Association of Brain‐Derived Neurotrophic Factor rs6265 G>A polymorphism and Post‐traumatic Stress Disorder susceptibility: A systematic review and meta‐analysis
Authors: Hu Xi‐Yi , Wu Yu‐Long , Cheng Chao‐Hui , Liu Xiao‐Xi , Zhou Lan 
Published: April 2021

AbstractBackgroundPrevious studies have shown that the brain‐derived neurotrophic factor (BDNF) rs6265 G > A polymorphism is closely related post‐traumatic stress disorder (PTSD) risk. However, the results were not consistent. We therefore conducted a meta‐analysis to explore the underlying relationships between BDNF rs6265 G > A polymorphism and PTSD risk.Materials and MethodsFive online databases were searched, and all related studies were reviewed up to July 1, 2020. Odds ratios (ORs) and corresponding 95% confidence intervals (CIs) were calculated to examine the statistical power of each genetic model. In addition, heterogeneity, sensitivity accumulative analysis, and publication bias were examined to check the statistical power.ResultOverall, 16 publications involving 5,369 subjects were included in this systematic review and 11 case‐control studies were analyses in meta‐analysis. The pooled results indicated an increasing risk of A allele mutations with PTSD risk. Moreover, the sequential subgroup analysis also demonstrated some similar situations in Asian populations and other groups.ConclusionCurrent meta‐analysis suggests that the BDNF rs6265 G > A polymorphism might be involved in PTSD susceptibility.
Tuning J‐aggregate Formation and Emission Efficiency in Cationic Diazapentacenium Dyes
Authors: Rodrigues Ana Clara B. , Wetterling Dario , Scherf Ullrich , Seixas de Melo J. Sérgio 
Published: April 2021

AbstractEnhancement of the luminescence efficiency of two new diazapentacenium salts (D1 and D2) of more than 55 for D1 and 22 times for D2) in poor solvents, acetonitrile and/or dichloromethane, was observed and rationalized as formation of emissive J‐aggregates. Both compounds displaying 4‐n‐decylphenyl substituents at the 7,14‐carbons and phenyl (D1) or 2,6‐difluorophenyl (D2) substituents at the quaternary nitrogen atoms in 5,12‐positions have been synthetized in a two‐step procedure involving a two‐fold Buchwald‐Hartwig‐type CN cross‐coupling and an electrophilic Friedel‐Crafts‐type cyclization. The optical properties of the dicationic diazapentacenium salts in various solvents and in thin films have been investigated by steady‐state and time‐resolved absorption and photoluminescence spectroscopies. In thin films and in good solvents, isolated molecules coexist with aggregates. Nonetheless, D1 is seven times more emissive than D2, reflecting a higher J‐aggregate contribution in the former.
Bis(Iminophosphorano)‐Substituted Pyridinium Ions and their Corresponding Bispyridinylidene Organic Electron Donors
Authors: Frenette Brandon L. , Arsenault Nadine , Walker Sarah L. , Decken Andreas , Dyker C. Adam 
Published: April 2021

AbstractOptimized synthetic procedures for pyridinium ions featuring iminophosphorano (−N=PR3; R=Ph, Cy) π‐donor substituents in the 2‐ and 4‐ positions are described. Crystallographic and theoretical studies reveal that the strongly donating substituents severely polarize the π‐electrons of the pyridyl ring at the expense of aromaticity. Moreover, the pyridinium ions are readily deprotonated to generate powerful bispyridinylidene (BPY) organic electron donors. Electrochemical studies show exceptionally low redox potentials for the two‐electron BPY/BPY2+couples, ranging from −1.71 V vs the saturated calomel electrode for3PhPh(with four Ph3P=N− groups) to −1.85 V for3CyCy(with four Cy3P=N− groups). These new compounds represent the most reducing neutral organic electron donors (OEDs) currently known. Some preliminary reductions involving3CyCyshowed enhanced capability owing to its low redox potential, such as the thermally activated reduction of an aryl chloride, but purification challenges were often encountered.
Tuning the Nanoaggregates of Sialylated Biohybrid Photosensitizers for Intracellular Activation of the Photodynamic Response
Authors: Almeida‐Marrero Verónica , Mascaraque Marta , Jesús Vicente‐Arana María , Juarranz Ángeles , Torres Tomás , de la Escosura Andrés 
Published: April 2021

AbstractIn the endeavor of extending the clinical use of photodynamic therapy (PDT) for the treatment of superficial cancers and other neoplastic diseases, deeper knowledge and control of the subcellular processes that determine the response of photosensitizers (PS) are needed. Recent strategies in this direction involve the use of activatable and nanostructured PS. Here, both capacities have been tuned in two dendritic zinc(II) phthalocyanine (ZnPc) derivatives, either asymmetrically or symmetrically substituted with 3 and 12 copies of the carbohydrate sialic acid (SA), respectively. Interestingly, the amphiphilic ZnPc‐SA biohybrid (1) self‐assembles into well‐defined nanoaggregates in aqueous solution, facilitating cellular internalization and transport whereas the PS remains inactive. Within the cells, these nanostructured hybrids localize in the lysosomes, as usually happens for anionic and hydrophilic aggregated PS. Yet, in contrast to most of them (e. g., compound2), hybrid1recovers the capacity for photoinduced ROS generation within the target organelles due to its amphiphilic character; this allows disruption of aggregation when the compound is inserted into the lysosomal membrane, with the concomitant highly efficient PDT response.
A factorization‐based algorithm to predict EMG data using only kinematics information
Authors: Manzano Marta , Serrancolí Gil 
Published: April 2021

AbstractEMG analyses have several applications, such as identifying muscle excitation patterns during rehabilitation or training plans, or controlling EMG‐driven devices. However, experimental measurements can be time consuming or difficult to obtain. This study presents a simple algorithm to predict EMG signals that can be applied in real time during running, given only the instantaneous vector of kinematics. We hypothesize that the factorization of the kinematics of the skeleton together with the EMG data of calibration subjects could be used to predict EMG data of another subject only using the kinematic information. The results showed that EMG signals of lower‐limb muscles can be predicted accurately in less than a second using this method. Correlation coefficients between predicted and experimental EMG signals were higher than 0.7 in 10 out of 11 muscles for most prediction trials and subjects, and their overall median value was higher than 0.8. These values confirm that this method could be used to accurately predict EMG signals in real time when only kinematics are measured.
Generation of Murine Bone Marrow and Fetal Liver Chimeras
Authors: Chappaz Stéphane , Saunders Tahnee L. , Kile Benjamin T. 
Published: April 2021

AbstractThe generation of radiation chimeras allows researchers to substitute the hematopoietic system of a mouse with that of one or more donors. A suspension of hematopoietic stem cells (HSCs) is prepared from the bone marrow (BM) or the fetal liver (FL) of a donor mouse and adoptively transferred into an irradiated recipient. Within days, the donor's HSCs will engraft, and their progeny will quickly replace the blood cells of the recipient. This simple tool, together with the large availability of genetically modified mouse lines, can be harnessed to manipulate and study various aspects of blood cell biology in vivo. We present here protocols to generate three types of radiation chimera: (1) BM chimeras, which can assist in determining whether the origin of a genetically based phenotype is the hematopoietic or radio‐resistant compartment and which are also conducive for studying the ecology of blood cells and for manipulating the environment hematopoietic cells live; (2) FL chimeras, which allow the study of hematopoietic systems from animals that carry genetic modifications incompatible with postnatal life; and (3) mixed BM chimeras, in which the hematopoietic system comprises blood cells of two different genotypes. Mixed BM chimeras can be used to identify genes that affect hematopoietic cell fitness and to establish whether secreted factors mediate a phenotype of interest. © 2021 Wiley Periodicals LLC.Basic Protocol 1: Generation of bone marrow chimeraBasic Protocol 2: Generation of fetal liver chimeraBasic Protocol 3: Generation of mixed bone marrow chimeraSupport Protocol 1: Isolation of bone marrow cellsSupport Protocol 2: Cell counting by flow cytometrySupport Protocol 3: Assessment of chimerism
Seed‐rain–successional feedbacks in wet tropical forests
Authors: Huanca Nuñez Nohemi , Chazdon Robin L. , Russo Sabrina E. 
Published: April 2021

AbstractTropical forest regeneration after abandonment of former agricultural land depends critically on the input of tree seeds, yet seed dispersal is increasingly disrupted in contemporary human‐modified landscapes. Here, we introduce the concept of seed‐rain–successional feedbacks as a deterministic process in which seed rain is shaped by successional dynamics internal to a forest site and that acts to reinforce priority effects. We used a combination of time series and chronosequence approaches to investigate how the quantity and taxonomic and functional composition of seed rain change during succession and to evaluate the strength of seed‐rain–successional feedbacks, relative to other deterministic and stochastic mechanisms, in secondary wet forests of Costa Rica. We found that both successional niches and seed‐rain–successional feedbacks shaped successional trajectories in the seed rain. Determinism due to successional niche assembly was supported by the increasing convergence of community structure to that of a mature forest, in terms of both functional and taxonomic composition. With successional age, the proportions of large‐seeded, shade‐tolerant species in the seed rain increased, whereas the proportion of animal‐dispersed species did not change significantly. Seed‐rain–successional feedbacks increased in strength with successional age, as the proportion of immigrant seeds (species not locally represented in the site) decreased with successional age, and the composition of the seed rain became more similar to that of the adult trees at the forest site. The deterministic assembly generated by seed‐rain–successional feedback likely contributed to the increasing divergence of secondary forest sites from each other during succession. To the extent that human modification of tropical forest landscapes reduces connectivity via factors such as forest cover loss, our results suggest that seed‐rain–successional feedbacks are likely to increasingly shape regeneration trajectories in and amplify floristic heterogeneity among tropical secondary forests.
Characterization of O+ Ion‐implanted Glassy Carbon Using the Superconducting Electron Cyclotron Resonance Ion Source and Selective Dopamine Detection
Authors: Park Jin Yong , Lee Dong‐Wook , Hong Jonggi , Kim Seong Jun , Ok Jung‐Woo , Yoon Jang‐Hee , Won Mi‐Sook 
Published: April 2021

AbstractThe O and N gas ions (O3+, O+, N2+, and N4+) were implanted on the glassy carbon surface employing the electron cyclotron resonance ion source, which were characterized using electrochemical and surface analysis methods. The modified electrode was examined for the catalytic oxidation of bioorganic molecules including dopamine, where the O+ ion implanted GC revealed the best catalytic performance. The XPS and Raman results represented that the ion implantation made enrichment in graphite nanocrystalline structure with edge plane, showing the enhanced electrochemical activity. It showed excellent performance for dopamine detection without significant interferences between 50.0 nM and 400.0 μM with the detection limit of 10.0±2.5 nM (95 % confidence level). The reliability of proposed electrode was evaluated by the real urine sample analysis.
Device uncertainty propagation in low‐ductility RC frames retrofitted with BRBs for seismic risk mitigation
Authors: Freddi Fabio , Ghosh Jayadipta , Kotoky Needhi , Raghunandan Meera 
Published: April 2021

AbstractPassive control systems, such as buckling‐restrained braces (BRBs), have emerged as efficient tools for seismic response control of new and existing structures by imparting strength and stiffness to buildings, while providing additional high and stable energy dissipation capacity. Systems equipped with BRBs have been widely investigated in literature; however, only a deterministic description of the BRBs’ properties is typically considered. These properties are provided by the manufacturer and are successively validated by qualification control tests according to code‐based tolerance limits. Therefore, the device properties introduced within the structure could differ from their nominal design estimates, potentially leading to an undesired seismic performance. This study proposes a probabilistic assessment framework to evaluate the influence of BRBs’ uncertainty on the seismic response of a retrofitted RC frame. For the case study, a benchmark three‐story RC moment‐resisting frame is considered where BRBs’ uncertainty is defined compatible to the standardized tolerance limits of devices’ quality control tests. This uncertainty is implemented through a two‐level factorial design strategy and Latin hypercube sampling technique. Cloud analysis and probabilistic seismic demand models are used to develop fragility functions for the bare and retrofitted frame for four damage states while also accounting for the uncertainty in the property of BRBs. Risk estimates are successively evaluated for three case study regions. The results show that, for the considered case study structure, these uncertainties could lead to an increase of fragility up to 21% and a variation in seismic risk estimates up to 56%.