bluuebunny/crossref_metadata_2025 huggingface dataset:
Model Eye Pictures can Lay the Foundation for Pictures Observed by Patients having Cataract Surgery while Simulation
Authors: Jandan Nisar Ahmed , Jamali Maqbool Ahmed , Rehman Ateeq , Abbasi Muhammad Ashfaque , Ghoto Abbas Ali , Ahmer Arslan
Published: April 2022

Aim: The photographs of a model eye during the fake waterfall are to be evaluated by medical treatment.

Methodology: This study was performed as a study in a research institution and a case procedure was carried out. Our current research was conducted at People Medical College Hospital, Nawabshah from April 2020 to March 2021. In the "front office" of a model eye, the iced rear surface was inserted with a flawed fogged focus, an acceptable intraocular focal point or an I/A tip. During the replicated Waterfall treatment, video pictures were collected from the back surface of the model eye. Before the waterfall surgery, 26 patients saw the video pictures and post-operatively rated their visual impressions.

Results: View from behind were pictures of the movable focal parts, the I/A tip and the IOL add-on. The image via the opiated focus point and the IOL has been the light of the meticulous enlargement lens from behind without moving objects. However, after IOL added, pictures of the tiny and working space were switched off from behind by the light of the magnifying equipment. 70% of patients reported the visual feel of shifting focal components as video cuts and 58%. The overwhelming majority of patients advised that the film before their intended medical operation should be viewed.

Conclusion: The model eye can re-enable visual insight for patients throughout the medical treatment for a waterfall. The preoperative view of the video pictures might aid to loosen the sufferers during the treatment.
Magnetic‐Powered Janus Cell Robots Loaded with Oncolytic Adenovirus for Active and Targeted Virotherapy of Bladder Cancer
Authors: Cong Zhaoqing , Tang Songsong , Xie Leiming , Yang Ming , Li Yangyang , Lu Dongdong , Li Jiahong , Yang Qingxin , Chen Qiwei , Zhang Zhiqiang , Zhang Xueji , Wu Song
Published: April 2022

A unique robotic medical platform is designed by utilizing cell robots as the active “Trojan horse” of oncolytic adenovirus (OA), capable of tumor‐selective binding and killing. The OA‐loaded cell robots are fabricated by entirely modifying OA‐infected 293T cells with cyclic arginine–glycine–aspartic acid tripeptide (cRGD) to specifically bind with bladder cancer cells, followed by asymmetric immobilization of Fe3O4 nanoparticles (NPs) on the cell surface. OA can replicate in host cells and induce cytolysis to release the virus progeny to the surrounding tumor sites for sustainable infection and oncolysis. The asymmetric coating of magnetic NPs bestows the cell robots with effective movement in various media and wireless manipulation with directional migration in a microfluidic device and bladder mold under magnetic control, further enabling steerable movement and prolonged retention of cell robots in the mouse bladder. The biorecognition of cRGD and robust, controllable propulsion of cell robots work synergistically to greatly enhance their tissue penetration and anticancer efficacy in the 3D cancer spheroid and orthotopic mouse bladder tumor model. Overall, this study integrates cell‐based microrobots with virotherapy to generate an attractive robotic system with tumor specificity, expanding the operation scope of cell robots in biomedical community.
Highly Efficient Quasi‐2D Green Perovskite Light‐Emitting Diodes with Bifunctional Amino Acid
Authors: Liu Chenwei , Liu Yongjie , Wang Shuxin , Liang Jiwei , Wang Cheng , Yao Fang , Ke Weijun , Lin Qianqian , Wang Ti , Tao Chen , Fang Guojia
Published: April 2022

Quasi‐two‐dimensional (quasi‐2D) perovskite light‐emitting diodes (PeLEDs) are considered as one of the most potential candidates in electroluminescence territory owing to their unique quantum confinement effect and excellent thermal stability of the light. Nevertheless, heterogeneous energy domain distribution leads to severe non‐radiative recombination in the process of energy transfer, which enormously hinders the performance and application of PeLEDs. Herein, an ambipolar amino acid, 5‐aminovaleric acid (5AVA), is demonstrated to be able to coordinate lead and halides simultaneously with its carboxyl and amidogen groups. The coordinated ambipolar molecule not only reconstitutes energy domains of perovskites but also minimizes the interfacial defects of PeLEDs. Accordingly, the presence of 5AVA in perovskite precursors leads to dramatic suppression of the n = 1 and n = 2 phases and accelerates energy transfer from wide bandgap domains to narrow bandgap ones. As a result, maximum external quantum efficiency (EQE) of 19.3% (18.20% ± 1.10%) is achieved in quasi‐2D green PeLEDs with current efficiency of 61.7 cd A−1.
Identification of Candidate Antigens and Immune Subtypes in Colon Cancer for mRNA Vaccine Development
Authors: Feng Huolun , Zhu Dandan , Zheng Jiabin , Lyu Zejian , Hu Weixian , Jiang Meiyu , Pan Zihao , Hou Tieying , Li Yong
Published: April 2022

The use of mRNA vaccines to treat colon cancer (CC) remains largely unexplored. The aim of this study is to identify CC antigens that may potentially be used for the development of anti‐CC mRNA vaccines and to select suitable patients for vaccination. Immune subtypes are identified by consensus clustering analysis, and the visualization of the CC immune landscape is performed by graph‐learning‐based dimensionality reduction. Plot cell trajectory and the WGCNA are applied to resolve the heterogeneity of the population suitable for vaccination. Four tumor antigens, COQ2, BGN, CASP6, and FAP, which are related to prognosis and infiltration of antigen‐presenting cells, are identified in CC. CC patients are divided into four immune subtypes characterized by differential molecular, cellular, pathological, and clinical features. Group B has the characteristics of immunologically “cold” tumors, and the immunosuppressive phenotype has worse survival than other groups. Moreover, different immune subtype tumors differed in the expression of immune checkpoints and immunogenic cell death modulators. Last, immune cell components in individual patients are revealed by the immune landscape. COQ2, BGN, CASP6, and FAP are potential antigens for use in a CC‐mRNA vaccine and suitable for patients in Group B.
Third reported patient with RAP1B‐related syndromic thrombocytopenia and novel clinical findings
Authors: Miller Dana , Saeed Azhar , Nelson Andrew C. , Bower Matthew , Aggarwal Anjali
Published: April 2022

RAP1B is a RAS‐superfamily small GTP‐binding protein involved in numerous cell processes. Pathogenic gain‐of‐function variants in this gene have been associated with RAP1B‐related syndromic thrombocytopenia, an ultrarare disorder characterized by hematologic abnormalities, neurodevelopmental delays, growth delay, and congenital birth defects including cardiovascular, genitourinary, neurologic, and skeletal systems. We report a 23‐year‐old male with a novel, de novo RAP1B gain‐of‐function variant identified on genome sequencing. This is the third reported case which expands the molecular and phenotypic spectrum of RAP1B‐related syndromic thrombocytopenia.
Hollow CoNiS polyhedrons/MnCoNi layered double hydroxide nanorod arrays on nickel foam as integral electrodes for improved oxygen evolution reaction in alkaline media
Authors: Shi Huafeng , Ni Yonghong
Published: April 2022

The oxygen evolution reaction (OER) with sluggish kinetics in electron transportation has been the key process to develop water splitting technology for the hydrogen production. Here, we successfully prepared hollow CoNiS polyhedrons/MnCoNi layered double hydroxide (MCN LDH) nanorod arrays on Ni foam (labeled as CNS/MCN LDH/NF) through a two‐step wet chemical route, employing NF‐supported MCN LDH nanoneedle arrays as the substrate. ZIF‐67 polyhedrons first loaded on MCN LDH to form ZIF‐67/MCN LDH/NF, and then ZIF‐67/MCN LDH/NF was sulfurized to obtain the final product. The investigations revealed that MCN LDH could not be sulfurized under the current sulfurization conditions and simultaneously nickel element entered the sulfurized product to form hollow CoNiS polyhedrons. Electrochemical tests showed that the as‐obtained CNS/MCN LDH/NF electrode merely required 259 mV of overpotential in 1.0 M KOH solution to deliver the current density of 50 mA cm−2, which was lower than 372 mV of the hollow Co9S8polyhedrons/NF electrode. Furthermore, the as‐constructed CNS/MCN LDH/NF electrode could continuously and stably work at the current density of 100 mA cm−2for 110 h, indicating its superb long‐term stability.
Resistance sensing response optimization and interval loading continuity of multiwalled carbon nanotube/natural rubber composites: Experiment and simulation
Authors: Liu Xingyao , Wang Yang , Li Rui , Yang Yang , Niu Kangmin , Fan Zhengming , Guo Rongxin
Published: April 2022

To achieve long‐term and real‐time monitoring of the deformation of isolation bearings, a conductive composite with a natural rubber (NR) matrix modified by multiwalled carbon nanotubes (MWCNTs) is processed by prestrain. The resistance‐strain response of this composite indicates excellent uniformity, linearity, hysteresis, reproducibility and stability due to the prestrain process for the composite before application. To explain the mechanism of the resistance‐strain response for the composite, a theoretical model is developed to analyze the relation between the conductivity and the MWCNT network structure. Mechanical and electrical testing under cyclic loads indicates that the prestrain of the composite could reduce or even eliminate the ‘shoulder peak’ effect of the resistance‐strain curve. Meanwhile, the resistance‐strain response behavior is independent of the prestrain temperature and discontinuous before and after the interval time. Furthermore, the coarse‐grained molecular dynamics simulation and microstructure testing indicate that the resistance‐strain response is induced by the changing orientation of MWCNT molecules in the rubber matrix under tension loading. All of the results and findings provide potential applications of this MWCNT/NR composite for deformation monitoring.
An insight on the effect of the hard segment domain on the thermo‐mechanical and surface properties of new piperazine‐based polyurethanes
Authors: Potolinca Violeta Otilia , Oprea Stefan
Published: April 2022

1,4‐piperazinediethanol was used as chain extender in the synthesis of new polyurethanes based on poly (tetramethylene oxide) glycol and 1,6‐hexamethylene diisocyanate. Also new polyurethanes which contain renewable cross‐linkers (polyethylene glycol sorbitan monolaurate (Tween® 20) and sorbitan monolaurate (Span® 20)) were obtained. The degree of microphase separation and the weight fraction of hydrogen‐bonded urethane groups is calculated by FTIR spectroscopy. The thermal, mechanical, and surface properties are examined and related with the structure of the corresponding polyurethanes. Linear polyurethanes have good thermal stability with the 5% weight loss in the range 250–280°C and cross‐linked samples in the range 295–320°C. Tensile strength and elongation at break have higher values (38 MPa and 1140%) when the 1,4‐piperazinediethanol content is lower. The increase in the piperazine content leads to more hydrophilic polyurethane surface. Cross‐linkers increase the water contact angle and thus the surface of the corresponding polyurethanes becomes hydrophobic.
Experimental investigation of optical anisotropy of polymethyl methacrylate aligned by metal–organic framework via in situ polymerization and direct chain‐introduction
Authors: Wang Lele , Wei Shuli , Wang Xianling , Lu Yunqing , Zhou Xinhui , Wang Jin
Published: April 2022

Encapsulating polymer materials into metal–organic frameworks (MOFs) is an effective strategy to enhance the optical anisotropy of polymers, by aligning the polymer chains within the ordered MOF channels. At present, the main methods to encapsulate polymers into the MOF channels are the in situ polymerization and the direct chain‐introduction. In this work, we use these two methods to incorporate and align polymethyl methacrylate (PMMA) chains in MOFs, and selectively remove the MOF template to obtain PMMAs. Through the experimental characterization of the encapsulation efficiency and the optical anisotropy, the fundamental difference and influence on the optical anisotropy of these two methods are analyzed. The results show that the adsorption capacity of PMMA chain encapsulated in the MOF channels via the in situ polymerization method is higher than that via the direct chain‐introduction method. Also, the morphology and structure of the isolated PMMA products are more regular and the optical anisotropy is stronger in the case of in situ polymerization.
Healable and reprocessable silica/poly(oxime‐urethane) composite elastomer with high mechanical robustness and exceptional damage‐tolerant capacity
Authors: Wang Hui , Xu Junhuai , Xing Dongming , Du Xiaosheng , Wang Haibo , Du Zongliang , Cheng Xu
Published: April 2022

A new generation of elastomer is expected to incorporate exceptional healing, reprocessing, damage‐tolerant capacity and outstanding strength and toughness in view of a sustainable society. To search a suitable method to perfectly match the overall performance is yet a formidable challenge. Here, a thermal‐triggered self‐healing polyurethane composite elastomer was fabricated by crosslinking isocyanate terminated polyurethane with amidoxime‐modified silica particles. The rigid fillers (silica particles) can effectively dissipate energy under an external force. The prepared particles and elastomer were detailly characterized by various instruments. The developed elastomer (POUs@2SiPs) had great tensile strength (39.47 MPa), decent elongation at break (1056.51%), excellent toughness (170.58 MJ m−3) and outstanding fracture energy (81.14 KJ m−2). Meanwhile, the well‐designed healing capability enabled the material to regain its original mechanical performance and integrity after damage. In addition, the reprocessibility granted material reusability to extend the service lifespan. This work is supposed to provide a meaningful strategy for developing the elastomer, which can effectively balance those conflict properties of mechanical strength, damage‐tolerant capacity and self‐healing.
Atomic Fe−N Doped Multi‐Cavity Hollow Carbon Nanoreactor as an Efficient Electrocatalyst for Lithium‐Sulfur Batteries
Authors: Shi Haodong , Su Panpan , Dong Cong , Liu Jian , Wu Zhong‐Shuai
Published: April 2022

Lithium‐sulfur (Li−S) batteries have been highly praised for the key rechargeable batteries due to their numerous advantages. However, the sluggish conversion and shuttling effect of polysulfides restrict their practicality. Here we rationally design the multi‐cavity hollow carbon spheres doped with atomic Fe−N sites (Fe−N/MCHCS) as physically/chemically double‐confined catalytic nanoreactors for the efficient sulfur host materials. The Fe−N/MCHCS with hierarchical porous structure and high pore volume ensures the high loading mass, and the multi‐cavity structures significantly buffer the volume expansion of sulfur and enhance the electronic contact. Meanwhile, atomic Fe offers chemical binding site and efficiently catalyzes the conversion of polysulfides during cycling, thus immobilizing and alleviating the shutting effect of polysulfides. Consequently, the Fe−N/MCHCS nanoreactor based Li−S batteries deliver a long cycling life of 1135 mAh g−1 after 300 cycles at 0.5 C and high‐rate capability of 1055 mAh g−1 at 8 C. Even under practical conditions with a high sulfur mass loading of 5.0 mg cm−2, a steady areal capacity of 4.85 mAh cm−2 is attained. This strategy combing multi‐cavity hollow carbon with single atom catalysis opens a reliable route to design highly stable and high‐performance Li−S batteries.
Hypernatremia in brain‐dead patients
Authors: Guo Weixin , Wang Shouhong , Wang Zhonghua , Hu Peihang , Wei Xuebiao , Liao Xiaolong
Published: April 2022

Objectives

Hypernatremia often occurs in patients with brain death. This study summarizes its characteristics.

Methods

We recorded 57 patient's highest blood sodium value, as well as daily NT‐proBNP, blood creatinine, and urine output. Further, we analyzed the time of the first rise in blood sodium, and the relationship between NT‐proBNP, serum creatinine, urine output, and serum sodium.

Results

There was no hyponatremia in these patients, and only seven of the 53 patients registered blood sodium between 137 and 150 mmol/L. We found that blood sodium started to rise at 36.0 (28.5–52.3) h, reaching the highest value in 79.0 (54.0–126.0) h. Urine volume and creatinine have no correlation with serum sodium level, while NT‐proBNP has a significant correlation with serum sodium level.

Conclusion

It is necessary to conduct volume assessments and urine electrolyte testing on patients with brain death. BNP has a protective effect on water and electrolytes to prevent hypernatremia.
Photocatalytic Biorefinery to Lactic Acid: A Carbon Nitride Framework with O Atoms Replacing the Graphitic N Linkers Shows Fast Migration/Separation of Charge
Authors: Ma Jiliang , Yang Xiaopan , Yao Shuangquan , Guo Yanzhu , Sun Runcang
Published: April 2022

The rational regulation of the structure of photocatalysts with an enhanced visible‐light absorption property and rapid charge dynamics is promising and challenging. Here, a facile method was developed for preparing oxygen‐doped carbon nitride bundles with porous hollow trunk‐shaped structures (Ox@CNB) using melamine with assistance of hydrochloric acid. Experimental results and density functional theory (DFT) calculations indicated that Ox@CNB exhibited controllable bandgaps (2.20–2.60 eV) and a low photoluminescence intensity. Interestingly, Ox@CNB displayed excellent photocatalytic activity for the synthesis of lactic acid (81.4 %) and universality for the reforming of biomass‐derived monosaccharides to lactic acid. The oxidation active species of h+, ⋅OH, ⋅O2− and 1O2 all promoted the lactic acid production, and h+ played a major role. A possible reaction mechanism of lactic acid synthesis was proposed by combining the experimental with the DFT results. A one‐thousand‐fold up‐scaled experiment demonstrated the significant application potential of the system for the industrial production of lactic acid.
Regulating Surface‐Interface Structures of Zn‐Incorporated LiAl‐LDH Supported Ru Catalysts for Efficient Benzene Hydrogenation to Produce Cyclohexene
Authors: Song Yihui , Sun Zhi , Fan Guoli , Yang Lan , Li Feng
Published: April 2022

In the heterogeneous catalysis, adsorption and desorption behaviors of reactants and products on the surface of catalysts can remarkably impact their catalytic activities and product selectivities. Here, series of Ru‐based catalysts supported on Zn‐incorporated Li−Al layered double hydroxides (Ru/LDH) were developed and employed in the selective benzene hydrogenation to produce cyclohexene without the use of any additional zinc salt additives. It was demonstrated that as‐constructed supported Ru catalyst bearing a Zn/(Li+Zn) molar ratio of 0.075 in the LDH support gave a higher cyclohexene yield of 43.2 % than those over other Ru‐based ones. Combining structural characterizations and catalytic hydrogenation reactions with temperature‐programmed desorption and in situ Fourier transform infrared spectroscopy of benzene and cyclohexene, it was revealed that the generation of appropriate surficial/interfacial Ru0/Ruδ+−O−Zn structures, as well as the existence of abundant hydroxyl groups on LDH supports, could facilitate the benzene adsorption and the cyclohexene desorption, thereby remarkably promoting the formation of cyclohexene. The present findings not only give a profound insight into the roles of surface‐interface structures of supported Ru catalysts for efficient benzene hydrogenation to produce cyclohexene but also simultaneously provide a promising guide to design high‐performance Ru‐based catalysts.
Palladium/Brønsted Acid Catalysis for Hydrofunctionalizations of Alkynes: From Tsuji‐Trost Allylations to Stereoselective Methodologies
Authors: Cera Gianpiero , Maestri Giovanni
Published: April 2022

Alkynes are one of the most abundant feedstocks for chemical transformations. By merging palladium and Brønsted acid catalysts, they are converted into reactive allylmetal species, which become suitable for Tsuji‐Trost functionalizations with complete atom‐economy. This approach, which overcomes the limitations of traditional methods that suffer from the formation of over‐stoichiometric amounts of by‐products, has been disclosed for developing new C−C and C−Het bond forming methodologies. Within this review, we aim to survey the latest advancements in this area including applications in polymer chemistry, deuterium‐labeling and stereoselective catalysis.
Insights into Substituent Effects of Benzaldehyde Derivatives in a Heterogeneous Organocatalyzed Aldol Reaction
Authors: Di Carmine Graziano , Pesciaioli Fabio , Wang Simeng , Sinibaldi Arianna , Giorgianni Giuliana , Parlett Christopher M. A. , Carlone Armando , D'Agostino Carmine
Published: April 2022

Organocatalyst immobilization onto solid supports represents a promising method for enabling asymmetric organocatalysis while retaining the advantages of heterogeneous catalysts, including catalyst separation, recycling, and the use of fixed‐bed reactors. Understanding how such heterogenized catalytic systems work is fundamental to develop and tailor more efficient ones. Herein, we have elucidated the role of reactant molecular structure on surface interactions and reactivity for asymmetric aldol reactions between benzaldehyde derivatives and hydroxyacetone catalyzed by SBA‐15 immobilized L‐proline. NMR relaxation time analysis reveals that a stronger interaction between the aldehyde and the catalyst surface reduces catalytic reactivity, which is attributed to reduced access of hydroxyacetone to the L‐proline surface sites, hence inhibiting the formation of the enamine intermediate between hydroxyacetone and L‐proline. The results show that surface phenomena in these systems are important considerations for reactant selection, opening up new directions to explore in this area of research.
Investigating the Role of Sulfate Groups for the Binding of Gd3+ Ions to Glycosaminoglycans with NMR Relaxometry
Authors: Werner Patrick , Schuenke Patrick , Krylova Oxana , Nikolenko Heike , Taupitz Matthias , Schröder Leif
Published: April 2022

Glycosaminoglycans (GAGs) are highly negatively charged macromolecules with a large cation binding capacity, but their interaction potential with exogeneous Gd3+ ions is under‐investigated. These might be released from chelates used as Gadolinium‐based contrast agents (GBCAs) for clinical MR imaging due to transmetallation with endogenous cations like Zn2+. Recent studies have quantified how an endogenous GAG sequesters released Gd3+ ions and impacts the thermodynamic and kinetic stability of some GBCAs. In this study, we investigate and compare the chelation ability of two important GAGs (heparin and chondroitin sulfate), as well as the homopolysaccharides dextran and dextran sulfate that are used as models for alternative macromolecular chelators. Our combined approach of MRI‐based relaxometry and isothermal titration calorimetry shows that the chelation process of Gd3+ into GAGs is not just a long‐range electrostatic interaction as proposed for the Manning model, but presumably a site‐specific binding. Furthermore, our results highlight the crucial role of sulfate groups in this process and indicate that the potential of a specific GAG to engage in this mechanism increases with its degree of sulfation. The transchelation of Gd3+ ions from GBCAs to sulfated GAGs should thus be considered as one possible explanation for the observed long‐term deposition of Gd3+ in vivo and related observations of long‐term signal enhancements on T1‐weighted MR images.
Children's shyness and frontal electroencephalogram delta–beta correlation in the pediatric surgical setting
Authors: Sriranjan Jhanahan , Chow Cheryl H.T. , Poole Kristie L. , Hassan Raha , Mirabelli James , Buckley Norman , Van Lieshout Ryan J. , Schmidt Louis A.
Published: April 2022

The prospect of surgery is a unique psychologically threatening context for children, often leading to experiences of preoperative anxiety. Recent research suggests that individual differences in children's temperament may influence responses to the surgical setting. In the present study, we examined whether individual differences in shyness were related to differences in frontal electroencephalogram (EEG) delta–beta correlation, a proposed neural correlate of emotion regulation and dysregulation, among children anticipating surgery. Seventy‐one children (36 boys, Mage = 10.3 years, SDage = 1.7 years) undergoing elective surgery self‐reported on their own shyness, and their parents also reported on their child's shyness. Using a mobile, dry sensor EEG headband, frontal EEG measures were collected and self‐ and observer‐reported measures of state anxiety were obtained at the children's preoperative visit (Time 1) and on the day of surgery (Time 2). A latent cluster analysis derived classes of low shy (n = 37) and high shy (n = 34) children using the child‐ and parent‐reported shyness measures. We then compared the two classes on frontal EEG delta–beta correlation using between‐ and within‐subjects analyses. Although children classified as high versus low in shyness had higher self‐ and observer‐reported state anxiety across both time periods, frontal EEG delta–beta correlation increased from T1 to T2 only among low shy children using a between‐subjects delta–beta correlation measure. We discuss the interpretation of a relatively higher delta–beta correlation as a correlate of emotion regulatory versus dysregulatory strategies for some children in a “real‐world,” surgical context.
A Review of Metal–Organic Framework‐Based Compounds for Environmental Applications
Authors: Qian Yongteng , Zhang Fangfang , Kang Dae Joon , Pang Huan
Published: April 2022

Metal–organic framework‐based compounds have recently gained great attention because of their unique porous structure, ordered porosity, and high specific surface area. Benefiting from these superior properties, metal–organic framework‐based compounds have been proven to be one of the most potential candidates for environmental governance and remediation. In this review, the different types of metal–organic framework‐based compounds are first summarized. Further, the various environmental applications of metal–organic framework‐based compounds including organic pollutant removal, toxic and hazardous gas capture, heavy metal ion detection, gas separation, water harvesting, air purification, and carbon dioxide reduction reactions are discussed in detail. In the end, the opportunities and challenges for the future development of metal–organic framework‐based compounds for environmental applications are highlighted.
Electrochemical Trifluoromethylselenolation of Activated Alkyl Halides
Authors: Grollier Kevin , Ghiazza Clément , Tlili Anis , Billard Thierry , Médebielle Maurice , Vantourout Julien C.
Published: April 2022

A practical electrochemical method for the generation of CF3Se− anion from a shelf‐stable reagent (TsSeCF3) is reported allowing the metal‐free trifluoromethylselenolation of activated alkyl halides. Trifluoromethylselenolated compounds have been obtained in modest to excellent yields under the optimized reaction conditions. Finally, cyclic voltammetric and 19F NMR studies are presented and allowed to gain insight into the reaction mechanism.
Microsatellite mutation frequencies in river otters (Lontra Canadensis) from the Athabasca Oil Sands region are correlated to polycyclic aromatic compound tissue burden
Authors: Gyasi Helina , Curry Jory , Browning Jared , Ha Kelsey , Thomas Philippe J. , O'Brien Jason M.
Published: April 2022

Mining activities in the Athabasca oil sands region (AOSR) have contributed to an increase of polycyclic aromatic compounds (PACs) locally. However, many PACs found in the AOSR, and the combined effects of PAC mixtures have not been evaluated for genotoxicity in wildlife. Here, we examine whether mutation frequencies in AOSR river otters are correlated to PAC tissue burdens. We used single‐molecule polymerase chain reaction (SM‐PCR) to measure the mutant frequency of unstable DNA microsatellite loci in the bone marrow of wild river otters (n = 11) from the AOSR. Microsatellite mutation frequencies were regressed against liver PAC burden (total, low/high molecular weight [LMW/HMW], and parent/alkylated PACs), and to the distances from where the samples were collected to nearby bitumen upgraders. We found that microsatellite mutation frequency was positively correlated with total liver PAC burden. LMW and alkylated PACs were detected at higher levels and had a stronger positive relationship with mutation frequency than HMW (alkylated and parent) PACs. There were no significant relationships detected between mutation frequency and LMW parent PACs or the distance from bitumen upgraders. Furthermore, pyrogenic and petrogenic signatures suggest PACs in animals with high mutation frequencies were associated with combustion processes; although further investigation is warranted, due to limitations of diagnostic ratio determination with biotic models. Our findings support the hypothesis that PACs found in the AOSR increase mutation frequency in wildlife. Further investigation is required to determine if the elevated PAC levels associated with higher mutation frequency are due to natural exposure or elevated human activity.
Efficient and Stable Perovskite Solar Cells based on Nitrogen‐Doped Carbon Nanodots
Authors: Collavini Silvia , Amato Francesco , Cabrera-Espinoza Andrea , Arcudi Francesca , Đorđević Luka , Kosta Ivet , Prato Maurizio , Delgado Juan Luis
Published: April 2022

The role of graphitic and amorphous nitrogen‐doped carbon dots (N‐CDs) as additives for perovskite solar cells (PSCs) is investigated. A detailed study of N‐CDs: perovskite (PVSK) blends through X‐ray diffraction, nuclear magnetic resonance, field emission scanning electron microscopy, UV–vis, and photoluminescence spectroscopy reveals the existence of interactions between N‐CDs and PVSK. The amorphous or graphitic nature of these carbon nanoforms, as well as the interactions between CDs and PVSK, clearly determines the photovoltaic outcome of the PSCs. Thus, a small amount of graphitic carbon dots (g‐N‐CDs) leads to more‐stable PSCs, while maintaining and even improving the power conversion efficiency (PCE). In addition, the long‐term evaluation of the g‐N‐CDs‐containing cells shows improvement of the PCE over time, up to 109% of the initial efficiency after 40 days while the reference performance is dropped to 86%.
Comparative thermoeconomic optimization and exergoenvironmental analysis of an ejector refrigeration cycle integrated with a cogeneration system utilizing waste exhaust heat recovery
Authors: Fazeli Atabak , Zandi Sina , Golbaten Mofrad Kamyar , Salehi Gholamreza , Khoshgoftar Manesh Mohammad Hassan , Shirmohammadi Reza
Published: April 2022

Two cogeneration cycles based on gas turbines have been compared by means of thermoeconomic and environmental analyses. The analyzed cogeneration systems are gas turbine, organic Rankine cycle (GT + ORC) and an integrated system including gas turbine, organic Rankine cycle, and ejector refrigeration cycle (GT + ORC + ERC). This work has focused on environmental considerations and thermoeconomic evaluation to decrease destruction cost and environmental impacts. The examination of cycles is conducted from energy, exergy, exergoeconomic, and exergoenvironmental (4E) perspectives. A computer MATLAB program is used to generate the simulation results, and the REFPROP 9.1 database is utilized to get thermodynamic properties of the working fluids. The use of the refrigeration evaporator in GT + ORC + ERC increased energy and exergy efficiencies. Multi‐objective optimization results indicate that the waste heat utilization in the trigeneration system is more effective in all aspects. In optimal conditions, the exergy efficiency and destruction cost of the GT + ORC + ERC system reached 40.76% and 151.95$ h−1, respectively. Moreover, optimization is performed by means of energy efficiency and destruction environmental impact as objective functions, and the optimum values are obtained at 30.67% and 46,918.30 mpts h−1, respectively.
Enantioselective Ecotoxicity of Venlafaxine in Aquatic Organisms: Daphnia and Zebrafish
Authors: Ribeiro Ondina , Félix Luís , Ribeiro Cláudia , Castro Bruno , Tiritan Maria Elizabeth , Monteiro Sandra Mariza , Carrola João Soares
Published: April 2022

Venlafaxine is a chiral antidepressant detected in aquatic compartments. It was recently included in the 3rd Watch List from the European Union. The present study aimed to investigate venlafaxine toxicity effects, targeting possible enantioselective effects, using two aquatic organisms, daphnia (Daphnia magna) and zebrafish (Danio rerio). Specimens were exposed to both racemate, (R,S)-venlafaxine (VEN), and to pure enantiomers. Acute assays with daphnia showed that up to 50 000 μg/L of the (R,S)-VEN induced no toxicity. Organisms were also exposed to sublethal concentrations (25–400 μg/L) of (R,S)-, (R)- and (S)-VEN, for 21 days. No significant effects on mortality, age at first reproduction, and size of the first clutch were observed. However, a decrease in fecundity was observed for both enantiomers at the highest concentration. Regarding zebrafish, the effects of venlafaxine on mortality, embryo development, behavior, biochemistry, and melanin pigmentation were investigated after 96 h of exposure to the range of 0.3–3000 μg/L. (R)-VEN significantly increased the percentage of malformations in comparison with (S)-VEN. Behavior was also enantiomer dependent, with a decrease in the total distance moved and an increase in avoidance behavior observed in organisms exposed to (R)-VEN. Despite the biochemical variations, no changes in redox homeostasis were observed. (R)-VEN also led to an increase in zebrafish pigmentation. The different susceptibility to venlafaxine and enantioselective effects were observed in zebrafish. Our results suggest that at environmental levels (R,S)-VEN and pure enantiomers are not expected to induce harmful effects in both organisms, but (R)-VEN increased malformations in zebrafish larvae, even at reported environmental levels. These results highlight the importance of including enantioselective studies for an accurate risk assessment of chiral pollutants. Environ Toxicol Chem 2022;41:1851–1864. © 2022 SETAC

Abstract

Venlafaxine (VEN) is a chiral antidepressant excreted by urine and/or leaked by inappropriate disposal and reach aquatic compartments. The present study investigated venlafaxine toxicity effects, targeting possible enantioselective effects, using daphnia (Daphnia magna) and zebrafish (Danio rerio) using several endpoints.
Evaluation and identification of morphological characters suitable for delimitation of Taraxacum species distributed in northeastern China
Authors: Jie Wu , Qun Liu , Cheng Haitao , Ning Wei , Cao Wei
Published: April 2022

Taraxacum germplasm resources in northeastern China are not current and do not accurately reflect the actual distribution of the species. The objective of this study was to investigate the morphological traits of Taraxacum species distributed in northeastern China and identify those that will facilitate their classification in this region. Leaf, flower, and achene characteristics of 18 species were used for morphological classification. Scanning electron microscopy (SEM) was used to examine pollen morphology. Internal transcribed spacer (ITS) sequences were analyzed to determine sequence differences among the species and their utility in delimitation. Taxa were classified into groups based on their morphology. The ITS sequence analysis supported the taxon classification, but the genetic distances among the taxa did not reflect morphological differences. Phylogenetic analysis was used to divide the 18 species into three groups. Group I: T. coreanum (which has white flowers). Group Ⅱ: T. heterolepis, T. sinomongolicum, T. variegatum, T. asiaticum var. lonchophyllum, T. falcilobum, T. brassicaefolium, and T. erythropodium (outer involucre bracts, narrow membranous or nonmembranous). Group Ⅲ: T. formosanum, T. liaotungense, T. mongolicum, T. borealisinense, T. ohwianum, T. platypecidum, T. urbanum, T. antungense, T. asiaticum, and T. junpeianum (outer involucre bracts, broad membranous). The main taxonomic characteristics of Taraxacum floral organs and achene morphology.
Duplication and nonregistration of COVID‐19 systematic reviews: Bibliometric review
Authors: Helliwell Jack A. , Thompson Joe , Smart Neil , Jayne David G. , Chapman Stephen J.
Published: April 2022

Objectives

This study examines the conduct of systematic reviews during the early stages of the COVID‐19 pandemic, including compliance to protocol registration and duplication of reviews on similar topics. The methodological and reporting quality were also explored.

Methods

A cross‐sectional, bibliometric study was undertaken of all systematic review manuscripts on a COVID‐19 intervention published between January 1st and June 30th, 2020. Protocol registration on a publicly accessible database was recorded. Duplication was determined by systematically recording the number of reviews published on each topic of analysis. Methodological quality and reporting quality were assessed using the AMSTAR‐2 and PRISMA 2009 instruments, respectively.

Results

Thirty‐one eligible systematic reviews were identified during the inclusion period. The protocol of only four (12.9%) studies was registered on a publicly accessible database. Duplication was frequent, with 15 (48.4%) of the 31 included studies focusing on either hydroxychloroquine (and/or chloroquine) or corticosteroids. Only one study (3.2%) was of “high” methodological quality, four (12.9%) were “low” quality, and the remainder (n = 26, 83.9%) were of “critically low” quality. The median completeness of reporting was 20 out of 27 items (74.1%) with a range of 5–26 (interquartile range: 14–23).

Conclusion

Systematic reviews during the early stages of the COVID‐19 pandemic were uncommonly registered, frequently duplicated, and mostly of low methodological quality. In contrast, the reporting quality of manuscripts was generally good but varied substantially across published reports. There is a need for heightened stewardship of systematic review research, particularly during times of medical crisis where the generation of primary evidence may be rapid and unstable.
Removal of acetic acid from aqueous post‐fermentation streams and fermented beverages using membrane contactors
Authors: Kaya Ezgi , Hasanoğlu Ayça
Published: April 2022

BACKGROUND

The removal of volatile organic acids from aqueous post‐fermentation wastewater streams and spoiled fermented liquid food was investigated using hollow‐fiber membrane contactors. Acetic acid, being the most common volatile acid in post‐fermentation products, was used to prepare acidic feed solutions. 1200–4000 ppm of aqueous acetic acid solutions with and without ethanol were prepared to assess the acid removal. Aqueous acetic acid solutions were used as model wastewater, while ethanol was included in the feed solutions to simulate the fermented beverages. Furthermore, the experiments were carried out using real spoiled wine to remove the excess acid. The feed solution was circulated through the shell side of the membrane contactor, while a reactive stripping solution of NaOH was circulated on the lumen side. Thus the acetic acid was transferred to the stripping solution by chemical absorption.

RESULTS

The effect of several process parameters including feed and stripping solution concentrations, temperature and solution flow rates on acid removal rate was investigated. Temperature had the most important effect on mass transfer. Experiments showed that acetic acid can be removed from aqueous solutions and recovered in the stripping phase efficiently. Up to 86% of the acetic acid could be removed from the feed solution.

CONCLUSION

This process is found to be effective for volatile organic acid removal from both industrial aqueous post‐fermentation waste streams and spoiled fermented liquid food. The theoretical model developed for the acetic acid transfer allows a flexible and predictable design of the system for further scale‐up studies. © 2022 Society of Chemical Industry (SCI).
Vertical structures of abrupt heavy rainfall events over southwest China with complex topography detected by dual‐frequency precipitation radar of global precipitation measurement satellite
Authors: Zhou Lingli , Xu Guirong , Xiao Yanjiao , Wan Rong , Wang Jixin , Leng Liang
Published: April 2022

Southwest China is with complex topography including basins, mountains, hills and plains, where abrupt heavy rainfall events (AHREs) occur frequently and are difficult to quantitatively estimate due to limited ground‐based observations. Using the data of ground rain gauges and GPM dual‐frequency precipitation radar during April to September in 2014–2020, this study investigates vertical structures of AHREs over southwest China. Both mass‐weighted mean diameter (Dm) and reflectivity (Ze) of AHREs increase rapidly in ice‐phase process but slowly in liquid‐phase process. For convective rainfall of AHREs, abundant water vapour and strong atmospheric convective motion cause higher Dm and Ze but lower generalized intercept parameter (dBNw) than those for stratiform rainfall. Moreover, ice‐phase process is active while liquid‐phase process is weak in the mountains, but the situation is opposite in the plains, which results in large‐size and low‐concentration raindrops in the mountains while small‐size and high‐concentration raindrops in the plains. Furthermore, statistical models of vertical profile of reflectivity (VPR) indicate that VPR patterns are affected by surface rain intensity and present different trends around the 0°C level between stratiform and convective rainfalls. In addition, higher rain top height in the mountains is conducive to ice‐phase process while lower terrain height in the plains is favourable for liquid‐phase process. Therefore, the VPR pattern depends on rain type, terrain and rainfall intensity, and its fine model is beneficial for understanding microphysical process of AHREs and improving quantitative precipitation estimation by ground‐based radars.
Spatiotemporal variation in precipitation concentration and its potential relationship with drought under different scenarios in Inner Mongolia, China
Authors: Du Walian , Guo Enliang , Wang Aoyang , Tong Zhijun , Liu Xingpeng , Zhang Jiquan , Guna Ari
Published: April 2022

Global warming has altered the uniformity of precipitation in Inner Mongolia, China, eventually leading to droughts. Further studies are necessary to determine the relationship between the concentration of precipitation and drought. Therefore, we assessed the spatial and temporal characteristics of the precipitation concentration degree (PCD), precipitation concentration period (PCP), and standardized precipitation evapotranspiration index (SPEI) in Inner Mongolia in the past (1961–2017) and predict changes in the three indices under different scenarios in the future (2018–2100) using measured model data and Sen's slope and Mann–Kendall trend analysis. The correlation between PCD/PCP and SPEI was explored using Pearson's correlation coefficient. The results showed that the spatial distribution of PCD and PCP in Inner Mongolia exhibited significant east–west differences. The PCD values were 0.42–0.76, with high‐value areas in the east. PCD showed a decreasing trend in both historical and future scenarios, indicating an even distribution of precipitation and an increased risk of drought. The PCP values were 190°–226°, with high‐value areas mainly in the western region. Except for in the Representative Concentration Pathways RCP4.5 and RCP8.5, PCP values in the historical and RCP2.6 scenarios showed a decreasing trend, indicating an earlier onset of maximum precipitation. SPEI values ranged between −1.23 and 1.17, with all future scenarios showing a decreasing trend and the historical scenario showing an increasing trend. The stations with positive correlation between SPEI and PCD accounted for 89.13, 67.39, 91.3, and 95.65% of Inner Mongolia, while those with positive correlation with PCP accounted for 43.47, 60.87, 56.52, and 4.35%, indicating that the correlation between drought variation and precipitation concentration is strong. These results can help reduce and prevent droughts and floods caused by changes in precipitation patterns and provide a basis for the rational use of water resources for preventing droughts and making relief decisions.
Dynamic simulation of debris flow waste‐shoal land use based on an integrated system dynamics–geographic information systems model
Authors: He Songtang , Wang Daojie , Zhao Peng , Chen Wenle , Li Yong , Chen Xiaoqing , Jamali Ali Akbar
Published: April 2022

Given the increased conflict between human development and land use in fragile mountainous areas, debris flow waste‐shoal land (DFWSL) use has shown beneficial effects and drawn public concern in recent years. However, temporal–spatial future change trends of DFWSL are not yet clear, meanwhile widely applied singular methods, including the system dynamics (SD) model and geographic information systems (GIS), are unsatisfactory. To better assess the sustainability and challenges of DFWSL use and provide reference for future development, we propose a hybrid SD–GIS model for characterizing complex relationships and performing dynamic simulations and spatial spreading. A causality flowchart was plotted and response equation defining the changes was established to predict macro land‐use demands in the SD model component. Additionally, the spatial distribution of land‐use types was determined using the GIS model component. The Awang DFWSL system in the Yunnan Province, China was analyzed using the coupled method. The results revealed a steadily declining trend in cultivated land and water areas accompanied by a substantial increase in construction land. Future projections indicate that from 2018 to 2025, the total area of cultivated land will decrease by nearly half compared with that in 2018 and decrease to one‐quarter of the level in 2018 by 2030. These predictions consider the reciprocal influences of social, economic, and ecological indicators, and risk factors, such as debris flow scale and frequency. This study provides a new approach for estimating future trends of DFWSL use and increases the awareness of the spatiotemporal changes encountered when using marginal land.
Synergetic evolution of the regional intellectual property management systems in China based on logistic model
Authors: Li Jinqiu , Zou Yuyou , Li Mingqiu
Published: April 2022

The synergetic evolution tracks of the order parameters of the regional intellectual property management systems in China showed significant regional difference, and the intensity of policy incentive mechanism affected the synergetic evolution of the intellectual property management system. The evolution tracks of the intellectual property development capability of different regions showed a steady upward trend and showed an evolution process from convergent ordered state to divergent disordered state, while the evolution tracks of the intellectual property protection capability and intellectual property operation capability of different regions were gentle and converged and had a stable conformity relation.