bluuebunny/crossref_metadata_2025_split huggingface dataset:
Interaction Regulation Between Ionomer Binder and Catalyst: Active Triple‐Phase Boundary and High Performance Catalyst Layer for Anion Exchange Membrane Fuel Cells
Authors: Cao Huixing , Pan Ji , Zhu Hairong , Sun Zhe , Wang Bowen , Zhao Junliang , Yan Feng 
Published: August 2021

AbstractAs one of the most crucial components, the catalyst layer (CL) plays a critical role in the performance of anion exchange membrane fuel cells (AEMFCs). However, the effect of the structural evolution of ionomer binder on the micromorphology and catalytic activity of CL is yet to be clarified. In this study, pyrrolidinum and quaternary ammonium cations are attached to the polyphenylene oxide (PPO) backbone through flexible spacer units (five, seven, or nine carbon atoms) with different terminal alkyl groups. The Van der Waals force and electrostatic repulsion between the ionomer binder and catalyst are regulated through the flexible spacer units and terminal alkyl groups to alleviate the agglomeration of catalyst particles and acquire a high catalytic activity. To evaluate the electrochemical stability of the cationic groups, the alkaline stability of the ionomer binder is tested under a constant voltage to simulate the true operational environment of the fuel cells. The results reveal that the degradation of the cation groups of ionomer binder is accelerated under a constant voltage condition. This phenomenon in neglect earlier, may serve as a useful reference for the synthesis and performance enhancement of ionomer binders.
Electrocatalytic acidic oxygen evolution reaction: From nanocrystals to single atoms
Authors: Ismail Nadia , Qin Fengjuan , Fang Chaohe , Liu Dan , Liu Bihan , Liu Xiangyu , Wu Zi‐long , Chen Zhuo , Chen Wenxing 
Published: August 2021

AbstractHydrogen is the most preferred choice as an energy source to replace the nonrenewable energy resources such as fossil fuels due to its beneficial features of abundance, ecofriendly, and outstanding gravimetric energy density. Splitting water through a proton exchange membrane (PEM) electrolyzer is a well‐known method of hydrogen production. But the major impediment is the sluggish kinetics of oxygen evolution reaction (OER). Currently, scientists are struggling to build out an acid‐stable electrocatalyst for OER with low overpotential and excellent stability. In this review, the reaction mechanism and characterization parameters of OER are introduced, and then the improvement method of metal nanocatalysts (noble metal catalysts and noble metal‐free catalysts) in acidic media is discussed. Particularly, the application of single‐atom catalysts in acidic OER is summarized, which is current researching focus. At the same time, we also briefly introduced the cluster phenomenon, which is easy to occur in the preparation of single‐atom catalysts. More importantly, we summarized the in situ characterization methods such as in situ X‐ray absorption spectroscopy, in situ X‐ray photoelectron spectroscopy, and so forth, which are conducive to further understanding of OER reaction intermediates and active sites. Finally, we put forward some opinions on the development of acidic OER.
Captive great apes tend to innovate simple tool behaviors quickly
Authors: Motes‐Rodrigo Alba , Tennie Claudio 
Published: August 2021

AbstractRecent studies have highlighted the important role that individual learning mechanisms and different forms of enhancenment play in the acquisition of novel behaviors by naïve individuals. A considerable subset of these studies has focused on tool innovation by our closest living relatives, the great apes, to better undestand the evolution of technology in our own lineage. To be able to isolate the role that individual learning plays in great ape tool innovation, researchers usually employ what are known as baseline tests. Although these baselines are commonly used in behavioral studies in captivity, the length of these tests in terms of number of trials and duration remains unstandarized across studies. To address this methodological issue, we conducted a literature review of great ape tool innovation studies conducted in zoological institutions and compiled various methodological data including the timing of innovation. Our literature review revealed an early innovation tendency in great apes, which was particularly pronounced when simple forms of tool use were investigated. In the majority of experiments where tool innovation took place, this occurred within the first trial and/or the first hour of testing. We discuss different possible sources of variation in the latency to innovate such as testing setup, species and task. We hope that our literature review helps researchers design more data‐informed, resource‐efficient experiments on tool innovation in our closest living relatives.
Die spannungsabhängige Richtung der Reprotonierung der Schiff'schen Base bestimmt das Einwärtspumpen von Xenorhodopsin
Authors: Weissbecker Juliane , Boumrifak Chokri , Breyer Maximilian , Wießalla Tristan , Shevchenko Vitaly , Mager Thomas , Slavov Chavdar , Alekseev Alexey , Kovalev Kirill , Gordeliy Valentin , Bamberg Ernst , Wachtveitl Josef 
Published: August 2021

AbstractDie neue Klasse der mikrobiellen Rhodopsine, genannt Xenorhodopine (XeR),[1] besitzen die besondere Eigenschaft des einwärtsgerichteten H+‐Pumpens.[2–4] Diese Pumpen stellen eine Alternative zu den in der Optogenetik etablierten Ionenkanäle (z. B. ChR1,2) dar, denn die Aktivierung von elektrisch anregbaren Zellen mit XeR ist unabhängig von den physiologischen Bedingungen ihrer Umgebung. In dieser Arbeit haben wir XeR aus Nanosalina (NsXeR)[1] funktionell und spektroskopisch charakterisiert. Das photodynamische Verhalten von NsXeR wurde auf einer ps‐ bis s‐Zeitskala untersucht und die Bildung des J, K und eines bisher unbekannten langlebigen Intermediats beobachtet. Die pH‐abhängige Kinetik zeigt, dass ein basisches Milieu den Photozyklus und den Pumpumsatz beschleunigen. In Patch‐Clamp‐Experimenten wird NsXeR im M‐Intermediat, durch Bestrahlung mit blauem Licht, eine spannungsabhängige Vektorialität der Photostromtransienten beobachtet, was auf die variable Zugänglichkeit zum Proton der Schiff'schen Base deutet. Des Weiteren konnten Einblicke in den kinetisch unabhängigen Switch‐Mechanismus durch Mutationsstudien vom mutmaßlichen H+‐Akzeptor D220 gewonnen werden.
New Mechanistic and Reaction Pathway Insights for Oxidative Coupling of Methane (OCM) over Supported Na2WO4/SiO2 Catalysts
Authors: Sourav Sagar , Wang Yixiao , Kiani Daniyal , Baltrusaitis Jonas , Fushimi Rebecca R. , Wachs Israel E. 
Published: August 2021

AbstractThe complex structure of the catalytic active phase, and surface‐gas reaction networks have hindered understanding of the oxidative coupling of methane (OCM) reaction mechanism by supported Na2WO4/SiO2 catalysts. The present study demonstrates, with the aid of in situ Raman spectroscopy and chemical probe (H2‐TPR, TAP and steady‐state kinetics) experiments, that the long speculated crystalline Na2WO4 active phase is unstable and melts under OCM reaction conditions, partially transforming to thermally stable surface Na‐WOx sites. Kinetic analysis via temporal analysis of products (TAP) and steady‐state OCM reaction studies demonstrate that (i) surface Na‐WOx sites are responsible for selectively activating CH4 to C2Hx and over‐oxidizing CHy to CO and (ii) molten Na2WO4 phase is mainly responsible for over‐oxidation of CH4 to CO2 and also assists in oxidative dehydrogenation of C2H6 to C2H4. These new insights reveal the nature of catalytic active sites and resolve the OCM reaction mechanism over supported Na2WO4/SiO2 catalysts.
The Voltage Dependent Sidedness of the Reprotonation of the Retinal Schiff Base Determines the Unique Inward Pumping of Xenorhodopsin
Authors: Weissbecker Juliane , Boumrifak Chokri , Breyer Maximilian , Wießalla Tristan , Shevchenko Vitaly , Mager Thomas , Slavov Chavdar , Alekseev Alexey , Kovalev Kirill , Gordeliy Valentin , Bamberg Ernst , Wachtveitl Josef 
Published: August 2021

AbstractThe new class of microbial rhodopsins, called xenorhodopsins (XeRs),[1] extends the versatility of this family by inward H+ pumps.[2–4] These pumps are an alternative optogenetic tool to the light‐gated ion channels (e.g. ChR1,2), because the activation of electrically excitable cells by XeRs is independent from the surrounding physiological conditions. In this work we functionally and spectroscopically characterized XeR from Nanosalina (NsXeR).[1] The photodynamic behavior of NsXeR was investigated on the ps to s time scale elucidating the formation of the J and K and a previously unknown long‐lived intermediate. The pH dependent kinetics reveal that alkalization of the surrounding medium accelerates the photocycle and the pump turnover. In patch‐clamp experiments the blue‐light illumination of NsXeR in the M state shows a potential‐dependent vectoriality of the photocurrent transients, suggesting a variable accessibility of reprotonation of the retinal Schiff base. Insights on the kinetically independent switching mechanism could furthermore be obtained by mutational studies on the putative intracellular H+ acceptor D220.
Construction of waste‐collagen modified superfine fiber substrates based on “click” chemistry: Moisture absorption and permeability
Authors: Xu Na , Xing Yanmei , Wang Xuechuan , Ren Longfang , Qiang Taotao 
Published: August 2021

AbstractSuperfine fiber synthetic leather is a high‐grade artificial leather product with numerous characteristics and advantages. However, compared with natural leather, it shows poor moisture absorption and moisture permeability, and it gives people a hot and tacky feeling; thus, the improvement of these properties has become a popular topic in the industry. In this paper, the “click” chemistry method was employed to modify the nylon fiber of the superfine fiber synthetic leather base with waste collagen to improve the moisture absorption and permeability of the superfine fiber synthetic leather base, thus enhancing the hygienic performance and wearing comfort of the end products, realizing waste recycling. This study obtained the optimal reaction conditions for the “click” modification of unfigured sea‐island superfine fiber synthetic leather base with collagen methacrylamide. The characterizations by static contact angle measurements, attenuated total reflection infrared spectroscopy, and X‐ray photoelectron spectroscopy analysis confirmed that collagen was successfully grafted onto the surface of the nylon fiber. Compared with the original base, the moisture absorption, and permeability of the base were improved by 602.4% and 43%, respectively. This study shows the theoretical research significance and excellent practical value for the resource utilization of skin collagen waste.
Application of a polymer inclusion membrane made of cellulose triacetate base polymer and trioctylamine for the selective extraction of bismuth(III) from chloride solutions
Authors: Ghaderi Narges , Dolatyari Leila , Kazemi Davood , Sharafi Hamid Reza , Shayani‐Jam Hassan , Yaftian Mohammad Reza 
Published: August 2021

AbstractA polymer inclusion membrane (PIM) prepared by casting a solution of cellulose triacetate (CTA), trioctylamine (TOA), and tri‐n‐butylphosphate (TBP), dissolved in dichloromethane was used for the extraction of bismuth(III) from hydrochloric acid solutions. The optimized PIM, in terms of mechanical properties and its efficiency for the extraction of bismuth(III), was consisted of CTA 40 wt%, TOA 25 wt%, and TBP 35 wt%. Contact angle measurements, FESEM, AFM, TGA, and stress–strain analysis were used for characterizing the PIM. A 3.5 cm diameter circular membrane segment of the PIM extracts quantitatively the bismuth ions (initial concentration 20 mg L−1) from 50 ml of 0.3 M HCl, after 120 min. The extracted bismuth was fully back‐extracted by shaking for 60 min of the loaded PIM with 50 ml solution of 2 M Na2CO3. It was confirmed that the extraction reaction involves the formation of the ion pair . The developed PIM was stable for using in four extraction/back‐extraction cycles of bismuth(III). This stability was enhanced to ten extraction/back‐extraction runs by replacing the plasticizer TBP with 2–nitrophenyloctyl ether or dibutyl phthalate. The investigated PIM showed excellent selectivity towards Bi(III) over Cu(II), Pb(II), Zn(II), Ni(II), Co(II), Cd(II), Fe(III), Cr(III), Mo(VI), W(VI), NO3−, and SO42−.
Physical modification approaches to enhance cell supporting potential of poly (vinyl alcohol)‐based hydrogels
Authors: Firoozi Mahtab , Entezam Mehdi , Masaeli Elahe , Ejeian Fatemeh , Nasr‐Esfahani Mohammad Hossein 
Published: August 2021

AbstractPVA‐based hydrogels with tissue engineered scaffolds application commonly need further modification to improve cell‐matrix interactions with respect to subsequent cell proliferation and differentiation. In this study, PVA‐modified hydrogels were formed by subjecting the solutions of PVA/Poly (R‐3‐hydroxybutyrate) (PHB), PVA/Extracellular Matrix (ECM), and PVA/PHB/ECM to freeze–thaw cycles and additive materials effect on cell supporting potential of the hydrogels was investigated. As, limited cell attachment and spreading were observed on PVA blended hydrogels, air plasma surface modification has been performed to promote cell attachment. Attenuated total reflection Fourier transform infrared (ATR‐FTIR) spectroscopy revealed the presence of some reactive bonds such as carbonyl on pure and amide on ECM‐coated PVA after plasma exposure. Atomic force microscopy (AFM) also proved increased roughness of hydrogel surface due to the plasma treatment. Plasma modification positive effect on cytoskeleton arrangement of cultured equine adipose derived stem cells (eASCs) was then confirmed by DAPI/phalloidin staining and scanning electron microscopy (SEM) imaging. In summary, among different physical modification approaches, coating with ECM fallowed by air plasma treatment had the most significant effect on cell‐hydrogel interactions. Thus, this combined modification method can be utilized to improve initial attachment and subsequent phenotype of cultured cells on PVA hydrogels for tissue engineering applications.
A novel nanocomposite of NH2‐MIL‐125 modified bismaleimide‐triazine resin with excellent dielectric properties
Authors: Li Xiaodan , Hu Xinyu , Liu Xiaoping , Liu Xiaoqing , He Rui , Liu Hongyu , Ling Xianzhang 
Published: August 2021

AbstractThe NH2‐MIL‐125 nanoparticles of amino‐functionalized titanium‐based metal organic frameworks were prepared by the solvothermal method and their nanocomposites with bismaleimide‐triazine resin (BT resin) were prepared. The research results showed that NH2‐MIL‐125 could significantly catalyze the curing reaction of BT resin to form triazine rings, which was attributed to the synergistic catalysis the self‐polymerization of cyanate ester by the amino group and Ti4+ in NH2‐MIL‐125. Because of the increase of triazine ring in crosslinking structures, the initial storage modulus of NH2‐MIL/BT nanocomposites improved. But the steric hindrance of NH2‐MIL‐125 brought the decrease on the crosslinking density and the increase on the free volume of nanocomposites. Meanwhile, besides the introduction of nanopores, the formation of more triazine rings and the increase of free volume, NH2‐MIL‐125 reduced the interface charge accumulation of nanocomposites through the Michael addition reaction with bismaleimide, which contributed to the reduction of dielectric constant of nanocomposites. In addition, NH2‐MIL‐125 with good dispersion played a toughening role and also improved the thermal stability and moisture resistance of nanocomposites. In this study, NH2‐MIL‐125 not only introduced nanopores but also changed crosslinking structures of BT resin, which provided a novel approach to obtain low‐dielectric materials.
A fluorescent screening method for optimization of conotoxin expression in Pichia pastoris
Authors: Zheng Lei , Lin Zeyin , Fan Haiping , Chen Mengxue , Yu Jiawei , Miao Ying , Wu Binghua 
Published: August 2021

AbstractConotoxins are small cysteine‐rich peptides secreted by the Conus venom glands, which act on ion channels or membrane receptors with high specificity and potency. Conotoxins are invaluable sources for neuroscience research and drug leads, but their application is hindered by the limited successes in quantitative engineering using either chemical or biotechnological approaches. Here, we explore the Pichia pastoris to express 23 selected conopeptides using a GFP‐based fluorescence screen. We found that, in a protease‐deficient strain PichiaPink™ Strain 4 (ade2 prb1 pep4), most of the recombinant conopeptides were expressed as two major folding variants including a compact form that was somehow resistant to reduction and high temperature. The GFP‐αTxIA was the only one displaying a single band that showed a dose‐dependent neurotoxicity on larvae of the insect Plutella xylostella, with a 48‐h LD50 lower than 1.12 pmol mg–1 body weight. Furthermore, the recombinant αTxIA after cleavage from the fusion was able to inhibit cell proliferation of the LYCT and HEK293T cell lines with an appearance IC50 of 341 ± 8 and 235 ± 15 nM, respectively. This screening method is straightforward and easy to scale up, providing a versatile tool for further optimization of conotoxin production in the yeast cell.
Preparation and characterization of a polyclonal antibody against PTEN‐Long
Authors: Yi Xianyanling , Wang Zhihong , Xiong Xingyu , Zheng Xiaonan , Peng Ge , Xu Hang , Wei Qiang , Li Hong , Zhu Ye , Ai Jianzhong 
Published: August 2021

AbstractPhosphatase and tensin homolog‐long (PTEN‐L) is a translational isoform of PTEN, which exists in both intracellular and extracellular locations. Previous studies demonstrated that PTEN‐L could inhibit oncogenesis due to its lipid phosphatase activity. However, recent studies found that PTEN‐L could promote the proliferation of some types of cancer cells. Moreover, as a protein phosphatase, PTEN‐L can suppress mitophagy by counteracting PTEN‐induced putative kinase protein 1 (PINK1)‐Parkin‐mediated ubiquitin phosphorylation, namely, PTEN‐L is critical for exploring the mitophagy progression and the treatment of mitochondrial diseases. Accounting for the critical functions of PTEN‐L, its antibody can be used for the treatment or prognosis of tumors and mitochondrial diseases. Currently, the commercial antibody of PTEN‐L is not available. In our study, the recombinant PTEN‐L protein was expressed in Escherichia coli BL21 and used as an antigen to immunize Japan's big‐eared white rabbit for the preparation of polyclonal antibody. The PTEN‐L protein can be captured by PTEN‐L antibody specifically and effectively. Taken together, a PTEN_L antibody is a valuable tool for further exploring the function of PTEN‐L in oncogenesis and mitochondrial diseases, and it would be a new choice for the prognosis or treatment of cancer and mitochondrial diseases.
Exposure management of a titanium‐reinforced dense polytetrafluoroethylene mesh used in a vertical ridge augmentation: A case report with 1‐year follow‐up
Authors: Belleggia Fabrizio 
Published: August 2021

AbstractIntroductionA new titanium‐reinforced dense polytetrafluoroethylene mesh (TR‐dPTFEM) has recently been introduced for vertical ridge augmentation (VRA). Since primary closure is required, the literature lacks information on its behavior in case of premature exposure. To the author's knowledge, this is the first report about TR‐dPTFEM complication management.Case PresentationA TR‐dPTFEM was used for the VRA in the molar region of the upper right maxilla. The defect was filled with a mix of particulate autogenous bone and porcine xenograft in a 1:1 ratio. A collagen membrane covered the hole pattern of the TR‐dPTFEM to prevent soft tissue growth within the grafted material during the first weeks. After a 4‐month uneventful healing period, a 4‐mm exposure occurred without infection. Patient was prescribed 0.2% chlorhexidine mouth rinse three times a day and manual cleansing with gauze soaked in 3% hydrogen peroxide, and was recalled for weekly follow‐up. One month later, the clinical situation was unchanged and the site was re‐entered. After TR‐dPTFEM removal, the regenerated tissue appeared to be covered with a thin layer of connective tissue. The favorable bone quality made it possible to obtain the primary stability of two implants. At implant uncovering, a gingival graft augmented the keratinized mucosa width. Two screw‐retained crowns were delivered 4 months after implant insertion and the 1‐year follow‐up showed perfectly maintained hard and soft tissues.ConclusionA late TR‐dPTFEM exposure, managed under strict hygiene control, did not affect this VRA. The augmented bone remained stable 1 year after prosthetic loading.Key pointsWhy is this case new information?

A novel titanium reinforced PTFE mesh has been recently introduced for vertical ridge augmentation. This case report adds new information to the literature about the management and clinical outcome in a case of exposure.
What are the keys to successful management of this case?

Weekly check‐up of the patient by the clinician
Patient's ability to keep the wound clean and disinfected
What are the primary limitations to success in this case?

Impossibility of being able to check the patient at least once a week
Acute infection
Disclosing the Role of Gold on Palladium – Gold Alloyed Supported Catalysts in Formic Acid Decomposition
Authors: Barlocco Ilaria , Capelli Sofia , Lu Xiuyuan , Bellomi Silvio , Huang Xiaohui , Wang Di , Prati Laura , Dimitratos Nikolaos , Roldan Alberto , Villa Alberto 
Published: August 2021

AbstractHerein, we report the synthesis of preformed bimetallic Pd‐Au nanoparticles supported on carbon nanofibers with different Pd : Au atomic ratio (nominal molar ratio: 8–2, 6–4, 4–6, 2–8) and the corresponding Pd and Au monometallic catalysts by sol immobilization method. The obtained materials were characterized thoroughly by Transmission Electron Microscopy (TEM), X‐ray photoelectron spectroscopy (XPS) and inductively coupled plasma optical emission spectroscopy (ICP‐OES). The catalytic performances of the Pd‐Au catalysts were evaluated in the aqueous phase dehydrogenation of formic acid (FA) at room temperature obtaining enhanced activity, stability and selectivity compared to the monometallic systems. In particular, Pd6Au4 and Pd8Au2 showed the best combination of catalytic properties, i. e., high selectivity to H2 and improved catalytic stability. Density functional theory (DFT) calculations on Pd15, Au15 and Pd9Au6 clusters supported on a carbon sheet were then simulated to provide atomic level understanding to the beneficial effect of gold observed in the experimental results. Au15 barely adsorb FA, while Pd15 possesses an adsorption energy higher than Pd9Au6. Dehydrogenation and dehydration pathways were followed on all these models. For Pd9Au6, the most favourable route was the formation of carbon dioxide and hydrogen. Analysis of the electronic structures was also performed on the different models showing a stronger interaction between the bimetallic system and the support proving the alloy superior stability.