bluuebunny/crossref_metadata_2025 huggingface dataset:
Humidity Resistant Carbon Nanotubes‐Styrene Methyl‐Methacrylate Polymer Composite for Ultrafast Laser
Authors: Bao Yunliang , Dai Lilong , Jiang Junjie , Huang Zinan , Huang Qianqian , Rozhin Aleksey , Mou Chengbo
Published: June 2022

Carbon nanotube (CNT)–polymer composite films are key elements in widespread photonic and optoelectronic applications. One particular successful application is to produce ultrashort optical pulses in the laser cavity. Nevertheless, such composite film may suffer from severe humidity/water degradation, from which the laser may even stop generating regular pulses. Here, surfactant‐free CNT–styrene methyl‐methacrylate polymer composite film is fabricated. Based on such film‐type saturable absorber, a self‐starting passively mode‐locked erbium‐doped fiber laser with the capability of generating≈1 ps pulses is demonstrated. From the perspective of experimental measurements and numerical simulations, the effectiveness of a saturable absorber in generating ultrashort pulses is confirmed. The operating composite film can survive under fully immersed water condition for 30 days. More importantly, after the non‐operating composite film has been fully soaked in the water tank for 2 days, it can still mode‐lock the laser as it is in dry air condition, confirming the humidity resistance capability. In addition, it is experimentally found that the mechanical packaging of the composite film has an impact on the survival time of composite film under water immersion.
Transition‐Metal‐Free Regioselective Direct C2, C4 Difunctionalization and C2, C4, C6 Trifunctionalization of Pyridines
Authors: Wang Dong , Xu Liqing , Zheng Shixin , Yang Xiaolong
Published: June 2022

This study reports the invention of di‐ or trifunctionalization of readily available pyridines (including all the pyridine substrates utilized in this paper, such as 3‐cyanopyridine and 3‐chloropyridine) through dearomative functionalization‐oxidative rearomatization under transition‐metal‐ and reductant‐free conditions. Although a two‐step operation is required, the crude product of the first step could be used in the next step directly. Typically, 3‐π‐EWG pyridines undergo difunctionalization, whereas 3‐σ‐EWG pyridines participate in trifunctionalization, affording multisubstituted piperidines. Computational studies provide detailed insights for their distinct reactivity in the title reaction.

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Palladium‐Catalyzed Domino Cyclization/Direct Aminosulfonylation Between Aryl Iodides and Amines via the Insertion of Sulfur Dioxide
Authors: Lv Haiping , He Xiaochun , Shen Lin , Zhang Xuemei , Lian Zhong
Published: June 2022

A palladium‐catalyzed domino cyclization/direct aminosulfonylation of aryl iodides with amines via the insertion of SO2 (from SOgen) was presented. This method could produce a series of oxindole‐based sulfonamides in moderate‐to‐good yields. A scale‐up reaction and two synthetic applications demonstrated the robustness and practicality of this transformation.

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Artificial Synapse Based on Bio‐Hierarchical Porous Memristor Driven by Multilevel‐Ions Migration
Authors: Zhang Jingjing , Ji Yuhang , Gao Qin , Gao Juan , Geng Xueli , Li Haoze , Shi Hongliang , Wang Mei , Xiao Zhisong , Chu Paul K. , Huang Anping
Published: June 2022

Artificial synapse with memristive characteristics has immense potential for neuromorphic computing due to their non‐volatile, adjustable conductance, and high integration. Herein, an artificial synapse based on the bio‐inspired hierarchical porous structure is demonstrated, which is composed of mixed‐dimensional porous MoS2 nanosheets (NS) and porous SiOx. The device produces analog memristive characteristics with a high on‐off ratio of 106 and a long retention time of 105 s. Diversity of synaptic plasticity is achieved, such as paired‐pulse facilitation, spike‐timing‐dependent plasticity, multilevel long‐term memory, and associative learning functions. Inspired by the hierarchical migration and storage of electrolyte ions in the natural bamboo membrane, the memristive mechanism is proposed. The systematical analysis of Raman scattering and conductive mechanism reveals multilevel‐ions dynamic in hierarchical porous structure, which results in multistep formation and maintenance of conductive paths for Li‐ions. The bio‐inspired synaptic device with multifunctional synaptic characteristics is expected to play an important role in the future applications of neuromorphic computing and artificial intelligence.
Industrial‐Level CO2Electroreduction Using Solid‐Electrolyte Devices Enabled by High‐Loading Nickel Atomic Site Catalysts
Authors: Wang Shuguang , Qian Zhengyi , Huang Qizheng , Tan Yingjun , Lv Fan , Zeng Lingyou , Shang Changshuai , Wang Kai , Wang Guoqing , Mao Yandong , Wang Yan , Zhang Qinghua , Gu Lin , Guo Shaojun
Published: June 2022

Transition‐metal atomic site catalysts (ASCs) are a new class of catalytic system for CO2electroreduction, however, their practical application is greatly hindered by the challenge that it's still difficult for them to simultaneously achieve industrial‐level current density and high selectivity. Herein a new strategy is reported for hundreds of gram‐scale and low‐cost production of Ni‐ASCs on 3D porous nanocarbon with high‐loading NiN3sites for greatly boosting the electroreduction of CO2to CO with both industrial‐level current density and high selectivity. It is discovered that although Ni‐ASCs with high‐loading (Ni‐ASCs/4.3 wt.%) and low‐loading (Ni‐ASCs/0.8 wt.%) both show above 95% Faradic efficiency for CO (FECO) under a wide potential range in H‐cell, in flow cell, Ni‐ASCs/0.8 wt.% can only achieve FECOof 43.6% at a current density of 343.9 mA cm−2, significantly lower than those (95.1%, 533.3 mA cm−2) of Ni‐ASCs/4.3 wt.% under same potential, first revealing the important role of high‐loadings of single atom sites in promoting the high‐selectivity electrolysis at industrial‐level current density. Most importantly, it is demonstrated that Ni‐ASCs/4.3 wt.%‐based membrane electrode assembly (MEA) exhibits outstanding durability at industrial‐level current density of 360.0 mA cm−2, which is one of the best performances for the realistic electroreduction of CO2to CO in the reported ASCs‐based MEA systems.
Revealing the Transient Formation Dynamics and Optoelectronic Properties of 2D Ruddlesden‐Popper Phases on 3D Perovskites
Authors: Kodalle Tim , Moral Raphael F. , Scalon Lucas , Szostak Rodrigo , Abdelsamie Maged , Marchezi Paulo E. , Nogueira Ana F. , Sutter‐Fella Carolin M.
Published: June 2022

Using in situ photoluminescence measurements during the spin‐coating and annealing steps, this study probes the formation of 2D layers on 3D triple cation perovskite films comparing phenylethylammonium and 2‐thiophenemethylammonium iodide bulky cations. This study elucidates the formation mechanisms of the surface layers for both cases and reveals two regimes during 2D layer formation: a kinetic‐driven and a thermodynamic‐driven process. These driving forces result in different compositions of the 2D/3D interface for each treatment, namely, different ratios of pure 2D (n = 1) and quasi‐2D (n > 1) structures. This study shows that a higher ratio of quasi‐2D phases is more beneficial for device performance, as pure‐2D layers may hamper current extraction. Due to a more evenly distributed formation energy profile among 2D and quasi‐2D phases, highly concentrated 2‐thiophenemethylammonium iodide appears to be more suited for effective surface passivation than its phenylethylammonium analog.
A consecutive‐competitive reaction system for assessing homogeneous and heterogeneous liquid–liquid mixing efficiency
Authors: Zhang Yi‐Dong , Wang Ze‐Xin , Zhang Liang‐Liang , Sun Bao‐Chang , Chu Guang‐Wen , Chen Jian‐Feng
Published: June 2022

Here, the consecutive‐competitive reaction system about aspirin and sodium hydroxide was proposed as a unified chemical probe to characterize the homogenous and heterogeneous liquid–liquid mixing. The kinetics of the reaction system was clearly studied. Then the mixing efficiencies were assessed in a standard stirred tank with this chemical probe and the obtained segregation index (XS) could well characterize the mixing performance. Based on the incorporation model, the estimation formula of micromixing time was established as . The chemical probe could show the influence of stirring intensity, interphase resistance, and two‐phase ratio on the mixing efficiency sensitively when it was extended to heterogeneous mixing. Using this chemical probe, we found the mixing efficiencies of homogeneous and heterogeneous process tended to be the same at sufficiently high stirring intensity. The reason for this phenomenon was unveiled by investigating the dispersed phase size and calculating mass transfer time.
Progress, Challenges, and Prospects of Soft Robotics for Space Applications
Authors: Zhang Yongchang , Li Pengchun , Quan Jiale , Li Longqiu , Zhang Guangyu , Zhou Dekai
Published: June 2022

The development of space robots is vital to broadening human cognitive boundaries. Space robots have been deployed in space science experiments, extravehicular operations, and deep space exploration. The application of space robots undoubtedly reduces the risk and cost of space activities. Traditional space robots primarily utilize rigid structures, resulting in limited degrees of freedom, which restricts their operational capabilities. In contrast, soft robots with greater flexibility and robustness may be used for future space exploration. Soft robots applied in space environments must overcome significant challenges associated with ultrahigh vacuum, microgravity, extreme temperatures, and high‐energy radiation. Herein, a comprehensive analysis of the key advantages of soft robots is presented based on the special requirements of the space environments for soft robots. Furthermore, brief insights into how soft robots must be changed in terms of their design, modeling, fabrication, sensing, and control to adapt to space environments are discussed. Specifically, soft robot scenarios with potential space application value are introduced. Finally, opinions regarding the potential directions of soft space robots are provided.
Bio‐inspirierte Ti3C2Tx MXene‐basierte Ionen‐Diodenmembran Für die Hocheffiziente Wandlung Osmotischer in Elektrische Energie
Authors: Ding Li , Zheng Mengting , Xiao Dan , Zhao Zihao , Xue Jian , Zhang Shanqing , Caro Jürgen , Wang Haihui
Published: June 2022

Bio‐inspirierte asymmetrische nanofluidische Ionenkanäle mit ionischem Diodenverhalten sind Forschungsziel, weil sie die effektive Umwandlung osmotischer Energie (sogenannte “blaue Energie”) in Elektrizität erlauben, insbesondere, wenn sie die Möglichkeit einer weiteren Oberflächenmodifizierung bieten. Zweidimensionale (2D) Metallcarbide und ‐nitride, bekannt als MXene, kombinieren hydrophile Oberflächen mit einstellbaren Oberflächenladungseigenschaften und bieten einen kurzschrittigen Weg zur Herstellung asymmetrischer nanofluidischer Ionenkanäle. Hier berichten wir über eine mechanisch robuste, flexible und scale up‐freundliche asymmetrische Ionen‐Diodenmembran auf Ti3C2Tx‐MXene‐Basis mit einem hochgradig gleichgerichteten Ionenstrom und demonstrieren ihre potenzielle Verwendung in der Wandlung osmotischer in elektrische Energie durch Umkehrelektrodialyse. Unter dem Salzkonzentrationsgradienten von synthetischem Meerwasser und Flusswasser beträgt die Leistungsdichte unseres Ionendioden‐Membran‐basierten Generators 8.6 W m−2 und bis zu 17.8 W m−2 bei einem 500‐fachen Salzgradienten und übertrifft damit den Stand der Technik. Das Design einer ionischen Membran vom Diodentyp auf MXene‐Basis bietet eine einfache und allgemeine Strategie für die Entwicklung von großflächigen 2D‐nanofluiden Systemen mit selektivem unidirektionalem Ionentransport.
Alcohols as Alkylating Agents in the Cation‐Induced Formation of Nitrogen Heterocycles
Authors: Cox Lydia , Zhu Yuxiang , Smith Philip J. , Christensen Kirsten E. , Sidera Portela Mireia , Donohoe Timothy J.
Published: June 2022

A Ti(Oi‐Pr)4 promoted 5‐ or 6‐endo‐trig cyclisation to make nitrogen heterocycles is presented. The utilisation of HFIP as a key solvent enables the stereoselective preparation of di‐ & tri‐substituted pyrrolidines and piperidines while forming a new C−C bond at the same time. The process is triggered by a cationic intermediate generated from an allylic or benzylic alcohol and leads to the simultaneous generation of both a C−C and a C−N bond in a single step. Notably, either 2,3‐trans‐ or 2,3‐cis‐substituted heterocycles can be obtained by using a nucleophilic amine bearing different substituents. Lastly, the stereoselective synthesis of enantiopure products was achieved by using readily available enantiopure acyclic starting materials.
Zirconium‐oxo Nodes of MOFs with Tunable Electronic Properties Provide Effective ⋅OH Species for Enhanced Methane Hydroxylation
Authors: Fang Geqian , Hu Jin‐Nian , Tian Ling‐Chan , Liang Jin‐Xia , Lin Jian , Li Lin , Zhu Chun , Wang Xiaodong
Published: June 2022

Direct conversion of methane to high value‐added oxygenates under mild conditions has attracted extensive interest. However, the over‐oxidation of target products is usually unavoidable due to the easily excessive activation of C−H bond on the sites of supported metal species. Here, we identified the most efficient Zr‐oxo nodes of UiO‐66 metal‐organic frameworks (MOFs) catalysts for the selective oxidation of methane with H2O2. These nodes were modified by three types of benzene 1, 4‐dicarboxylates (NH2‐BDC, H2BDC, and NO2‐BDC). Detailed characterizations and DFT calculations revealed that these ligands can effectively tune the electronic properties of Zr‐oxo nodes and the H2BDC ligand led to optimal electronic density of Zr‐oxo nodes in UiO‐66. Thus the UiO‐66‐H catalyst promoted the formation of ⋅OH species that adsorbed on Zr‐oxo nodes, and facilitated the activation of methane with a lower energy barrier and subsequent conversion to hydroxylation oxygenates with 100 % selectivity.
Bioinspired Ti3C2TxMXene‐Based Ionic Diode Membrane for High‐Efficient Osmotic Energy Conversion
Authors: Ding Li , Zheng Mengting , Xiao Dan , Zhao Zihao , Xue Jian , Zhang Shanqing , Caro Jürgen , Wang Haihui
Published: June 2022

Bioinspired asymmetric nanofluidic ion channels with ionic diode behavior that can boost the osmotic energy (so‐called blue energy) conversion are highly desirable, especially if they can be easily constructed and modified. Two‐dimensional (2D) metal carbides and nitrides, known as MXenes, combine hydrophilic surfaces and tunable surface charge properties, providing a shortcut to prepare asymmetric nanofluidic ion channels. Here, we report a mechanically robust, flexible, and scale‐up‐friendly asymmetric Ti3C2TxMXene‐based ionic diode membrane with a highly rectified current and demonstrate its potential use in reverse electrodialysis osmotic energy conversion. Under the salinity gradient of synthetic seawater and river water, our ionic diode membrane‐based generator‘s power density is 8.6 W m−2and up to 17.8 W m−2at a 500‐fold salinity gradient, outperforming the state‐of‐the‐art membranes. The design of MXene‐based ionic diode‐type membrane provides a facile and general strategy in developing large‐scale 2D nanofluidics and selective ion transport.
Hexagonal Planar [B6H6] within a [B6H12] Borate Complex: Structure and Bonding of [(Cp*Ti)2(μ‐ɳ6 : ɳ6‐B6H6)(μ‐H)6]
Authors: Kar Sourav , Bairagi Subhash , Haridas Anagha , Joshi Gaurav , Jemmis Eluvathingal D. , Ghosh Sundargopal
Published: June 2022

Isolation of planar [B6H6] is a long‐awaited goal in boron chemistry. Several attempts in the past to stabilize [B6H6] were unsuccessful due to the domination of polyhedral geometries. Herein, we report the synthesis of a triple‐decker sandwich complex of titanium [(Cp*Ti)2(μ‐η6 : η6‐B6H6)(μ‐H)6] (1), which features the first‐ever experimentally achieved nearly planar six‐membered [B6H6] ring, albeit within a [B6H12] borate. The small deviation from planarity is a direct consequence of the predicted structural pattern of the middle ring in 24 Valence Electron Count (VEC) triple‐decker complexes. The large ring size of [B6H6] in 1 brings the metal–metal distance into the bonding range. However, significant electron delocalization from the M−M bonding orbital to the bridging hydrogen and B−B skeleton in the middle decreases its bond strength.
Silicate composition of sungrazing comet C/1965 S1 (Ikeya‐Seki)
Authors: Petrov Dmitry V. , Zhuzhulina Elena A.
Published: June 2022

The sungrazing comets, that pass extremely close to the Sun, are rare, but are of considerable scientific interest due to their unusual polarimetric properties. This paper is devoted to the interpretation of polarimetric observational data from comet Ikeya‐Seki (C/1965 S1), also known as the “Big Comet of 1965.” The data of polarimetric observations of this comet at a wavelength of 0.53 μm are sharply out of the general range of other observed comets in the wavelength range of 0.52–0.55 μm. The phase curve of comet Ikeya‐Seki, unlike all other comets, has an incredibly steep slope, the exact explanation of which has not been given so far. In this work, we reproduce this slope using computer simulation. It was shown that irregularly shaped particles under no parameters can give such a sharp slope in the degree of linear polarization. However, the use of spherical particles is able to reproduce this slope quite accurately. The best fit is achieved using Fe‐rich silicate (fayalite) particles with a radius of ≈0.633 μm. Therefore, when studying near‐solar comets, it is necessary to consider the effect on the scattering pattern of regular shape particles as well as the presence of Fe‐rich silicate (fayalite) material.
BIM‐Pilotprojekte Huntebrücke und Grawiedebrücke – Erfahrungen mit dem Werkzeug BIM in der Entwurfsplanung
Authors: von der Haar Christoph , Gudat Alexander , Thiele Dietmar , Göhlmann Joachim
Published: June 2022

Die Entwurfsplanungen für die Ersatzneubauten der Huntebrücke und der Grawiedebrücke wurden von der Niedersächsischen Landesbehörde für Straßenbau und Verkehr (NLStBV) als BIM‐Pilotprojekte ausgewählt. Während die Grawiedebrücke mit einer Gesamtstützweite von 9 m eine Landstraße über die Grawiede überführt, überführt die Huntebrücke mit einer Gesamtstützweite von 441 m die Autobahn 29 östlich von Oldenburg über die Seeschifffahrtsstraße Hunte. Diese beiden sehr gegensätzlichen Bauwerke werden im Rahmen des folgenden Beitrags vorgestellt und die Erfahrungen seitens der Entwurfsverfasser mit dem Werkzeug BIM geschildert. Beide Ersatzneubauten wurden dreidimensional modelliert, die Bauabläufe mit den Modellen verknüpft und anschließend die Mengenermittlungen und Kostenberechnungen anhand der Modelle durchgeführt. Damit entsprach die Modellierungstiefe einer vollständigen 5D‐BIM‐Simulation. Es werden die Vorteile und die Herausforderungen, die aus der Planung der Ersatzneubauten mit der Methode BIM resultierten, aufgezeigt.
Early detection of risk of reading difficulties using a working memory assessment battery
Authors: Atkinson Susan J. , Martin Colin R.
Published: June 2022

Research suggests a role for aspects of the working memory system in reading. While much of the evidence points to a role for working memory capacity and the phonological loop, more recent work indicates a role for the central executive component, although findings remain unclear. There is an identified need for a reliable screening measure for risk of reading difficulties in children who are pre‐readers. Recent research suggests that working memory measures may contribute to such a measure in addition to existing tests of phonological ability, non‐verbal reasoning, motor skills and language. One hundred and two children aged between 56 and 69 months were assessed on measures of reading accuracy, working memory capacity, processing speed and a range of measures designed to assess central executive functioning. Linear regression, discriminant function analysis and confirmatory factor analysis were conducted to determine the predictive qualities and factor structure of the working memory assessment battery. Discriminant function analysis indicated that the working memory assessment battery was able to significantly discriminate between children who were at risk and not at risk of reading difficulties (as indicated by an independent measure). Linear regression and Confirmatory Factor Analysis revealed that the tests were a good predictor of the later outcome, particularly the alliteration fluency and sentence verification tasks. Therefore, the working memory assessment battery promises to be a useful screening measure for potential reading difficulties in educational settings, facilitating early effective intervention.
Bro1 family proteins harmonize cargo sorting with vesicle formation
Authors: Tseng Chun‐Che , Piper Robert C. , Katzmann David J.
Published: June 2022

The Endosomal Sorting Complexes Required for Transport (ESCRTs) drive membrane remodeling in a variety of cellular processes that include the formation of endosomal intralumenal vesicles (ILVs) during multivesicular body (MVB) biogenesis. During MVB sorting, ESCRTs recognize ubiquitin (Ub) attached to membrane protein cargo and execute ILV formation by controlling the activities of ESCRT‐III polymers regulated by the AAA‐ATPase Vps4. Exactly how these events are coordinated to ensure proper cargo loading into ILVs remains unclear. Here we discuss recent work documenting the ability of Bro1, an ESCRT‐associated Ub‐binding protein, to coordinate ESCRT‐III and Vps4‐dependent ILV biogenesis with upstream events such as cargo recognition.
Development and validation of a prognostic model for esophageal carcinoma based on immune microenvironment using system bioinformatics
Authors: Fu Chenchun , Feng Shicheng , Wang Sheng , Su Xiangyu
Published: June 2022

Esophageal cancer (EC) is an aggressive malignancy that accounts for numerous cancer‐related deaths worldwide. The multimodal combination therapy approach can be potentially used to treat EC effectively. However, distinct biomarker of significant specificity are still needed to develop individualized treatment strategies and provide accurate prognostic predictions. Therefore, we aimed to investigate the associated genes subtypes identified were, IFN‐γDominant, Inflammatory, Lymphocyte Depleted, etc. and construct a risk model based on these genes to predict the overall survival (OS) of patients suffering from EC. Three immune subtypes were defined in the Cancer Genome Atlas (TCGA) cohort with different tumor microenvironment (TME) and clinical outcomes based on radio‐differentiated immune genes. Subsequently, a risk model of immune characteristics included the immune cell infiltration levels and pathway activity was developed based on the genomic changes between the subtypes. In the TCGA dataset, as well as in subgroup analysis with different stages, gender, age, and pathological type, a high‐risk score was identified as an adverse factor for OS using the method of the univariate Cox regression analysis and tROC analysis. Furthermore, it was observed that the high‐risk group was characterized by depleted immunophenotype, active cell metabolism, and a high tumor mutation burden (TMB). The low‐risk group was characterized by high TME abundance and active immune function. Differences in the biological genotypes may account for the differences in the prognosis and treatment response. Extensive research was carried out, and the results revealed that the low‐risk group exhibited a significant level of therapeutic advantage in the field of immunotherapy. A risk model was developed based on the immune characteristics. It can be used to optimize risk stratification for patients suffering from EC. The results can potentially help provide new perspectives on treatment methods.
Single‐image human mesh reconstruction by parallel spatial feature aggregation
Authors: Li Shasha , Liu Yuehu , Su Wei
Published: June 2022

Recovering human mesh from a single image with natural postures is a challenging task in human modeling and animation. Model‐free methods regress the mesh vertices from the input image directly to avoid the 6‐DoF human joint extraction from the 2D image. However, the missing of the global information in spatial feature aggregation of the existing GNNs may result in the undesired deformity and inaccuracy of the recovered human mesh. To address this issue, we propose a parallel‐aggregating network with a novelly designed global layer for spatial feature extracting from random walk normalized matrix. Moreover, the coarse body mesh (head, hand, foot, etc.) provided by the coarsening network can add the human characteristic to the mesh. The local and global spatial features are aggregated to update vertice coordinates following an iterative, coarse‐to‐fine process to obtain an accurate and smooth human mesh. Experiments validated the effectiveness and robustness of the proposed approaches for single‐image human mesh recovery.
Sincere or exciting? Brand personality and argument quality on brand attitude
Authors: Jiao Jinfeng (Jenny) , Levin Irwin P. , Gaeth Gary J. , Chatterjee Subimal
Published: June 2022

The purpose of this paper is to examine whether strong arguments provided in a commercial perform the same for exciting and sincere brands. Across three experiments, we vary brand personality (exciting versus sincere brands) and supporting argument quality (strong vs. weak), and find that consumers have more favorable attitudes toward sincere brands when the argument quality is strong rather than weak, but strong/weak argument quality does not influence consumers' attitudes toward exciting brands. The findings contribute to the existing literature on the elaboration likelihood model, sheds new light on the interaction between brand personality and argument quality, and suggest ways for advertising managers to customize content messaging in their commercials depending upon the personality of the focal brand's audience.
Regioselective Biocatalytic C4‐Prenylation of Unprotected Tryptophan Derivatives
Authors: Eggbauer Bettina , Schrittwieser Joerg H. , Kerschbaumer Bianca , Macheroux Peter , Kroutil Wolfgang
Published: June 2022

Regioselective carbon−carbon bond formation belongs to the challenging tasks in organic synthesis. In this context, C−C bond formation catalyzed by 4‐dimethylallyltryptophan synthases (4‐DMATSs) represents a possible tool to regioselectively synthesize C4‐prenylated indole derivatives without site‐specific preactivation and circumventing the need of protection groups as used in chemical synthetic approaches. In this study, a toolbox of 4‐DMATSs to produce a set of 4‐dimethylallyl tryptophan and indole derivatives was identified. Using three wild‐type enzymes as well as variants, various C5‐substituted tryptophan derivatives as well as N‐methyl tryptophan were successfully prenylated with conversions up to 90 %. Even truncated tryptophan derivatives like tryptamine and 3‐indole propanoic acid were regioselectively prenylated in position C4. The acceptance of C5‐substituted tryptophan derivatives was improved up to 5‐fold by generating variants (e. g. T108S). The feasibility of semi‐preparative prenylation of selected tryptophan derivatives was successfully demonstrated on 100 mg scale at 15 mM substrate concentration, allowing to reduce the previously published multistep chemical synthetic sequence to just a single step.
Successes with metacognition: Empowering faculty and transforming student learning
Authors: Voorhees David H. , LeMay Lynsey E. , Nagy Elizabeth A. , Perez Adriana E.
Published: June 2022

Bringing metacognition onto college campuses is a transformational experience for students and faculty as well as their institutions. In this chapter, we share a collection of metacognitive activities and describe their value in and outside of the classroom based upon our experiences in the community college setting. These activities are easily implemented and help students take ownership of their learning.
High‐performance flexible perovskite photodetectors based on single‐crystal‐like two‐dimensional Ruddlesden–Popper thin films
Authors: Liang Chao , Gu Hao , Xia Junmin , Liu Tanghao , Mei Shiliang , Zhang Nan , Chen Yonghua , Xing Guichuan
Published: June 2022

Two‐dimensional Ruddlesden−Popper (2DRP) perovskites have attracted intense research interest for optoelectronic applications, due to their tunable optoelectronic properties and better environmental stability than their three‐dimensional counterparts. Furthermore, high‐performance photodetectors based on single‐crystal and polycrystalline thin‐films 2DRP perovskites have shown great potential for practical application. However, the complex growth process of single‐crystal membranes and uncontrollable phase distribution of polycrystalline films hinder the further development of 2DRP perovskites photodetectors. Herein, we report a series of high‐performance photodetectors based on single‐crystal‐like phase‐pure 2DRP perovskite films by designing a novel spacer source. Experimental and theoretical evidence demonstrates that phase‐pure films substantially suppress defect states and ion migration. These highly sensitive photodetectors show Ilight/Idark ratio exceeding 3 × 104, responsivities exceeding 16 A/W, and detectivities exceeding 3 × 1013 Jones, which are higher at least by 1 order than those of traditional mixed‐phase thin‐films 2DRP devices (close to the reported single‐crystal devices). More importantly, this strategy can significantly enhance the operational stability of optoelectronic devices and pave the way to large‐area flexible productions.
Beads‐on‐string hierarchical structured electrocatalysts for efficient oxygen reduction reaction
Authors: Yuan Yang , Zhang Qing , Li Yinling , Lv Luyao , Hou Yan , Li Ge , Fu Jing , Yang Lin , Bai Zhengyu
Published: June 2022

Rational design of hierarchically structured electrocatalysts is particularly important for electrocatalytic oxygen reduction reaction (ORR). Here, ZIF‐67 crystals are stringed on core–shell Ag@C nanocables using a coordination‐modulated process. Upon pyrolysis, Ag@C strings of Co nanoparticles embedded with three‐dimensional porous carbon with beads‐on‐string hierarchical structures are developed. Due to the advantages of the rich electrochemical active sites of Co‐based “beads” and the efficient electron transfer pathways via Ag@C “strings,” the resultant NH3–Ag@C@Co–N–C‐700 catalyst shows an improved electrocatalytic activity toward ORR. NH3–Ag@C@Co–N–C‐700 shows a high onset potential of 0.99 V versus RHE, a high half‐wave potential of 0.88 V versus RHE, and a large limiting current of 5.8 mA cm−2, which are better than those of commercial Pt/C electrocatalysts. Additionally, the NH3–Ag@C@Co–N–C‐700 catalyst shows high stability and preeminent methanol tolerance, which makes NH3–Ag@C@Co–N–C‐700 a promising catalyst for oxygen electrocatalysis in fuel cell applications.
Synthesis and Biological Evaluation of Water‐Soluble Esterase‐Activated CO‐Releasing Molecules Targeting Mitochondria
Authors: Hemmersbach Lars , Schreiner Yannick , Zhang Xinmiao , Dicke Finn , Hünemeyer Leon , Neudörfl Jörg‐Martin , Fleming Thomas , Yard Benito , Schmalz Hans‐Günther
Published: June 2022

Due to the beneficial effects of carbon monoxide as a cell‐protective and anti‐inflammatory agent, CO‐releasing molecules (CORMs) offer some promising potential applications in medicine. In this context, we synthesized a set of acyloxy‐cyclohexadiene‐Fe(CO)3 complexes, all displaying a N‐methyl‐pyridinium triflate moiety in the ester side chain, as mitochondria‐targeting esterase‐triggered CORM prodrugs. Whereas the compounds in which the acyloxy substituent is attached to the 2‐position of the diene‐Fe(CO)3 unit (A series) spontaneously release CO upon dissolution in phosphate buffer, which remarkably is partly suppressed in the presence of porcine liver esterase (PLE), the 1‐substituted isomers (B series) show the expected PLE‐induced release of CO (up to 3 equiv.). The biological activity of Mito‐CORMs 2/3‐B and their isophorone‐derived analogs 2/3‐A’, which also displayed PLE‐induced CO release, was assessed by using human umbilical vein endothelial cells (HUVEC). Whereas Mito‐CORMs 2/3‐B were not cytotoxic up to 500 μM (MTT assay), Mito‐CORMs 2/3‐A’ caused significant toxicity at concentrations above 50 μM. The anti‐inflammatory potential of both Mito‐CORM variants was demonstrated by concentration‐dependent down‐regulation of the pro‐inflammatory markers VCAM‐1, ICAM‐1 and CXCL1 as well as induction of HO‐1 in TNFα‐stimulated human umbilical vein endothelial cells (HUVECs; western blotting and qPCR). Energy phenotyping by seahorse real‐time cell metabolic analysis, revealed opposing shifts of metabolic potentials in cells treated either with Mito‐CORMs 2/3‐B (increased mitochondrial respiration and glycolytic activity) or Mito‐CORMs 2/3‐A’ (suppressed mitochondrial respiration and increased glycolytic activity). Thus, the Mito‐CORMs represent valuable tools for the safe and targeted delivery of CO to mitochondria as a subcellular compartment to induce positive anti‐inflammatory effects with only minor shifts in cellular energy metabolism. Also, due to their water solubility, these compounds provide a promising starting point for further pharmacological studies.
Water Sorption Controls Extreme Single‐Crystal‐to‐Single‐Crystal Molecular Reorganization in Hydrogen Bonded Organic Frameworks
Authors: Boer Stephanie A. , Conte Luke , Tarzia Andrew , Huxley Michael T. , Gardiner Michael G. , Appadoo Dominique R. T. , Ennis Courtney , Doonan Christian J. , Richardson Christopher , White Nicholas G.
Published: June 2022

As hydrogen bonded frameworks are held together by relatively weak interactions, they often form several different frameworks under slightly different synthesis conditions and respond dynamically to stimuli such as heat and vacuum. However, these dynamic restructuring processes are often poorly understood. In this work, three isoreticular hydrogen bonded organic frameworks assembled through charge‐assisted amidinium⋅⋅⋅carboxylate hydrogen bonds (1C/C, 1Si/C and 1Si/Si) are studied. Three distinct phases for 1C/C and four for 1Si/C and 1Si/Si are fully structurally characterized. The transitions between these phases involve extreme yet recoverable molecular‐level framework reorganization. It is demonstrated that these transformations are related to water content and can be controlled by humidity, and that the non‐porous anhydrous phase of 1C/C shows reversible water sorption through single crystal to crystal restructuring. This mechanistic insight opens the way for the future use of the inherent dynamism present in hydrogen bonded frameworks.
Sustainable ternary treatment system for greywater and potential reuse
Authors: Prasad Rajnikant , Sharma Dayanand , Yadav Kunwar D. , Ibrahim Hussameldin
Published: June 2022

Adopting a greywater treatment system that provides economical, effective, and sustainable treated greywater over a longer span helps to address water scarcity. The present study focuses on treating greywater generated from hostels using a floating plant treatment system (FPTS) planted with water hyacinth. The additional units, a sand filter and an activated charcoal filter, were attached in series to FPTS to improve the treated greywater quality. The treatment system was operated for 90 days with daily monitoring of influent and effluent parameters. The treatment performance was evaluated based on the removal efficiency for total suspended solids (TSS), turbidity, chemical oxygen demand (COD), ammonia, sulphate, phosphate, and faecal coliform (FC) of 74.81% ± 5.74%, 99.76% ± 0.05%, 95.70% ± 4.10%, 99.16% ± 2.08%, 48.22% ± 1.80%, and 100%, 97.27% ± 1.48%, respectively. The study showed that the system effectively treats greywater, making it suitable for non‐potable purposes on educational institution's campuses.
Organization of neural systems expressing melanocortin‐3 receptors in the mouse brain: Evidence for sexual dimorphism
Authors: Bedenbaugh Michelle N. , Brener Samantha C. , Maldonado Jose , Lippert Rachel N. , Sweeney Patrick , Cone Roger D. , Simerly Richard B.
Published: June 2022

The central melanocortin system is fundamentally important for controlling food intake and energy homeostasis. Melanocortin‐3 receptor (MC3R) is one of two major receptors of the melanocortin system found in the brain. In contrast to the well‐characterized melanocortin‐4 receptor (MC4R), little is known regarding the organization of MC3R‐expressing neural circuits. To increase our understanding of the intrinsic organization of MC3R neural circuits, identify specific differences between males and females, and gain a neural systems level perspective of this circuitry, we conducted a brain‐wide mapping of neurons labeled for MC3R and characterized the distribution of their projections. Analysis revealed MC3R neuronal and terminal labeling in multiple brain regions that control a diverse range of physiological functions and behavioral processes. Notably, dense labeling was observed in the hypothalamus, as well as areas that share considerable connections with the hypothalamus, including the cortex, amygdala, thalamus, and brainstem. Additionally, MC3R neuronal labeling was sexually dimorphic in several areas, including the anteroventral periventricular area, arcuate nucleus, principal nucleus of the bed nucleus of the stria terminalis, and ventral premammillary region. Altogether, anatomical evidence reported here suggests that MC3R has the potential to influence several different classes of motivated behavior that are essential for survival, including ingestive, reproductive, defensive, and arousal behaviors, and is likely to modulate these behaviors differently in males and females.
A study on color conspicuity and color harmony of wayfinding signs according to outdoor environment types
Authors: Yi Ji Hyun , Jeon Junryeol
Published: June 2022

Wayfinding signs must have prominent visibility in the environment to provide people with the information they need to navigate to an intended destination. Therefore, designers seek to design signs that are clearly visible while esthetically harmonious with the ambient environment. To find highly conspicuous colors, 1632 images showing combinations of various colors and environments were created. And then evaluation factors such as sign conspicuity, color contrast, color harmony, sign color preference, and expected sign usability were tested with 33 designers. Through statistical analysis of experimental results, the colors with high conspicuity and harmony were organized in different types of environments, and all correlations between the evaluation factors were analyzed. The results showed that all evaluation factors had a significantly high correlation except color harmony. Based on these results, we conclude that when designing a sign, it should focus on increasing the sign conspicuity by using color difference rather than color harmony between the sign and the ambient environment.
Application of deep learning in the detection and practical evaluation of ski resort teaching area
Authors: Chen Xiangxian , Qi Xiang , Lyu Pin
Published: June 2022

The teaching land of ski resorts provides learning sites for beginners of skiing. The teaching sites of different ski resorts are different. When selecting teaching scenes, we need to focus on the safety of the site. The focus of our research is to detect more suitable teaching land in the whole ski resort and evaluate its practical indicators. In order to accurately detect the teaching area in the snow field, we propose a method based on deep learning. The algorithm innovatively optimizes the convolution network. The experiment combines convolutional neural network with recurrent neural network for training, and uses the output of convolutional neural network to train recurrent neural network, so as to continuously predict the next optimal teaching area in the sequence. The purpose of training is to optimize the detection result area. The experimental results show that the model can better detect the sites suitable for teaching in the snow field.
Complete Set of Diketopyrrolopyrrole Centrosymmetrical Cofacial Stacked Pairs
Authors: Luňák Stanislav , Weiter Martin , Vala Martin
Published: June 2022

Stacked centrosymmetrical dimers and simultaneously H‐bonded and stacked hexamers of thiophene‐substituted diketopyrrolopyrrole (ThDPP) were studied using DFT as models for crystals with slipped‐stacked molecules in 1D columns. Eight stacked dimer arrangements were found, six of which are driven by the minimisation of electron repulsion and realised by placing the partially negatively charged atoms of the diketopyrrolopyrrole rings below the centre of an adjacent thiophene ring. Four of these stacks are related to N,N'‐dialkylated derivatives of ThDPP found in the literature, while a further one is related to an N,N'‐diacylated derivative. An analogous set of eight stacks was discovered computationally for phenyl‐substituted DPP (PhDPP), four of which are known among H‐bonded DPP pigments, and one more among N,N'‐dialkylated PhDPP derivatives. The results shed more light on the mechanisms that drive the formation of stacks between nonaromatic (DPP) and aromatic (Th, Ph) rings. The excitation energies of the lowest four singlet states computed by TD DFT enabled excitonic coupling and energy separation between Frenkel‐resonance‐type and charge‐transfer states to be established, depending on the equilibrium stack geometry.
Public participation in peace negotiations between the Colombian government and the National Liberation Army (ELN): An opportunity to redress power asymmetry and enhance the insurgents' readiness
Authors: Mouly Cécile , Hernández Delgado Esperanza
Published: June 2022

This article examines the centrality of the participation of society in the peace process between the Colombian government and the National Liberation Army (ELN) that initiated during the Santos administration, in the light of readiness theory. It does so on the basis of over 60 interviews with key respondents, documents from delegations to the negotiating table, as well as secondary sources. It analyses the importance of this point for the ELN on ideological and pragmatic grounds, and the government's perspective on it. It argues that such a participation was key to rebalance the perceived power asymmetry between the government and ELN, increasing this guerrilla group's optimism about a dignified exit and hence its readiness to engage in talks. In particular, the ELN considered that, by making social groups stakeholders in the peace process, these groups could put pressure on the government to agree on, and implement, provisions towards social transformation. In so doing, this article contributes to debates on how to enhance weaker parties' readiness to negotiate an end to internal armed conflict, as well as on how public participation in peace processes could be useful in this regard.
Urea derivatives carrying a thiophenylthiazole moiety: Design, synthesis, and evaluation of antitubercular and InhA inhibitory activities
Authors: Keleş Atıcı Rüveyde , Doğan Şengül Dilem , Gündüz Miyase Gözde , Krishna Vagolu Siva , Chebaiki Melina , Homberset Håvard , Lherbet Christian , Mourey Lionel , Tønjum Tone
Published: June 2022

The recent emergence of drug‐resistant strains of Mycobacterium tuberculosis (Mtb) has complicated and significantly slowed efforts to eradicate and/or reduce the worldwide incidence of life‐threatening acute and chronic cases of tuberculosis. To overcome this setback, researchers have increased the intensity of their work to identify new small‐molecule compounds that are expected to remain efficacious antimicrobials against Mtb. Here, we describe our effort to apply the principles of molecular hybridization to synthesize 16 compounds carrying thiophene and thiazole rings beside the core urea functionality (TTU1–TTU16). Following extensive structural characterization, the obtained compounds were initially evaluated for their antimycobacterial activity against Mtb H37Rv. Subsequently, three derivatives standing out with their anti‐Mtb activity profiles and low cytotoxicity (TTU5, TTU6, and TTU12) were tested on isoniazid‐resistant clinical isolates carrying katG and inhA mutations. Additionally, due to their pharmacophore similarities to the well‐known InhA inhibitors, the molecules were screened for their enoyl acyl carrier protein reductase (InhA) inhibitory potentials. Molecular docking studies were performed to support the experimental enzyme inhibition data. Finally, drug‐likeness of the selected compounds was established by theoretical calculations of physicochemical descriptors.
Hemostasis using a covered self‐expandable metal stent for pseudoaneurysm bleeding from the perihilar bile duct
Authors: Ishii Yu , Nakayama Akihiro , Kikuchi Kazuo , Nakatani Kei , Konda Kenichi , Mori Daichi , Nishihara Shigetoshi , Oikawa Shu , Nomoto Tomohiro , Usami Tomono , Noguchi Toshihiro , Mitsui Yuta , Yoshida Hitoshi
Published: June 2022

Although there are many reports of hemostasis with covered self‐expandable metal stent (CSEMS) for bleeding from the papilla of Vater and the intrapapillary and distal bile duct, there are rare reports of its use for hemostasis in the perihilar bile duct. We report the case of a patient undergoing supportive care for perihilar cholangiocarcinoma with acute cholecystitis after side‐by‐side placement of uncovered SEMS for perihilar bile duct obstruction. Percutaneous transhepatic gallbladder aspiration was performed upon admission, and hematemesis occurred the next day. Since computed tomography scanning showed a pseudoaneurysm in the right uncovered SEMS, hemostasis by interventional radiology (IVR) was performed thrice for massive bleeding; however, hemostasis could not be achieved. When endoscopic retrograde cholangiopancreatography was performed for scrutiny and treatment of melena and increased hepatobiliary enzyme, the endoscopic visual field could not be secured by bleeding, and changes in hemodynamics were observed; thus, IVR was required, but it was difficult to perform. Since bleeding from the right bile duct was expected, hemostasis was performed using CSEMS. This is the first report of hemostasis performed by placing a covered SEMS for bleeding from a pseudoaneurysm of the intrahepatic bile duct.
Directly Spun Epoxy‐Crosslinked Polyethylenimine Fiber Sorbents for Direct Air Capture and Postcombustion Capture of CO2
Authors: Wilfong Walter C. , Wang Qiuming , Ji Tuo , Baker James S. , Shi Fan , Yi Shouliang , Gray McMahan L.
Published: June 2022

A novel, directly‐injected solid fiber sorbent is synthesized from a solvent‐stable, epoxy‐crosslinked basic immobilized amine sorbent (BIAS) for CO2 capture. Leach resistance of the BIAS organics toward 1‐methyl‐2‐pyrrolidone/H2O (90/10, fiber solvent) reaches near 100% at the expense of CO2 capture and is achieved by increasing the extent of crosslinking. The optimized fiber sorbent, prepared with an N,N‐diglycidyl‐4‐glycidyloxyaniline/polyethylenimine (PEI)‐0.35/1 wt. ratio, retains 79.2% of PEI and captures 0.37 (direct air capture [DAC]) and 0.67 (postcombustion) mmol CO2g‐fiber−1. A nonoptimized prototype hollow fiber exhibits a stable 0.2 mmol CO2g‐fiber−1 during DAC cycling and is assembled into a ten‐fiber module. These results demonstrate a large step toward practical application of this material.