bluuebunny/crossref_metadata_2025 huggingface dataset:
Homogeneity versus Parsimony in Markov Manpower Models: A Hidden Markov Chain Approach
Authors: Ossai Everestus O. , Ezra Precious N. , Ohanuba Felix O. , Eze Martin N.
Published: December 2022

We aim at tackling the problem of inadequate specification of a Markov manpower model in this paper, by formulating a procedure for validating the inclusion or non-inclusion of some transition parameters in the model. The mover-stayer principle and its extensions are employed to incorporate hidden classes in the model to achieve more homogeneity and this is compared with the model without the hidden classes, which is more parsimonious, using Likelihood ratio statistic, Akaike Information Criterion and Bayesian Information Criterion. The illustration shows a case of manpower data where, up to a certain level of hidden states, homogeneity is more important than parsimony.
Change of Some Soil Physical Properties in Newly Reclaimed Soils Following Poor Soil Management: A Case Study in Al-Qasasin, Egypt
Authors: Hussien E. A. Abou , Abou-Baker N. H. , Fotoh M. S. M. Abou Al , Kotb E. K. M.
Published: December 2022

Background: In newly reclaimed areas, some improper farming practices like using heavy machines in tillage, adding excessive quantity of fertilizers, irrigation by flooding method and intensity cultivation could affect the soil physical properties.

Objective‎: Therefore, eighty soil samples were collected from the twenty-seven profiles to evaluate the change of soils' physical properties at four locations (A, B, C and D) after different improper soil managements.

Methods‎: The study area is located in Al-Qasasin, Ismailia Governorate, Egypt northern tip of it extended between latitudes 30° 33' 1.147" N and 30° 28' 16.096" N, and longitudes 32° 4' 12.984" E and 32° 4' 15.696" E, with total area of 144.25 km2 (34345.1 Feddan) which falls in the semi-arid zone. Profile depth, soil texture, total porosity (TP), bulk density (BD), hydraulic conductivity (HC) and infiltration rate (IR) were determined according to the standard procedures.

Results: According to the values of general mean of the studied properties in the four locations, BD takes the order: C>B>A>D. While the TP take the opposite trend of BD (D>A>B>C), on the other hand, both HC and IR follow the same order: C>A>B>D. These results attributed to that the locations B and D using surface flooding irrigation system, while A and C locations using sprinkler and drip irrigation systems, respectively. In addition to the intensive cultivation and the conventional tillage planting system are used in the B and D locations. Where the tillage tools like heavy plows, disks or chisels are used seasonally. While in A and C sites light tillage and orchards planting only are used commonly.

Conclusion: These findings should be considered in future research to improve the soil management programs in these examined areas particularly the fourth location that should stop flooding technique and terns to the drip or sprinkler method.
Association of Hearing Aids and Cochlear Implants With Cognitive Decline and Dementia
Authors: Yeo Brian Sheng Yep , Song Harris Jun Jie Muhammad Danial , Toh Emma Min Shuen , Ng Li Shia , Ho Cyrus Su Hui , Ho Roger , Merchant Reshma Aziz , Tan Benjamin Kye Jyn , Loh Woei Shyang
Published: December 2022

Importance

Hearing loss is associated with cognitive decline. However, it is unclear if hearing restorative devices may have a beneficial effect on cognition.

Objective

To evaluate the associations of hearing aids and cochlear implants with cognitive decline and dementia.

Data Sources

PubMed, Embase, and Cochrane databases for studies published from inception to July 23, 2021.

Study Selection

Randomized clinical trials or observational studies published as full-length articles in peer-reviewed journals relating to the effect of hearing interventions on cognitive function, cognitive decline, cognitive impairment, and dementia in patients with hearing loss.

Data Extraction and Synthesis

The review was conducted in accordance with Preferred Reporting Items for Systematic Review and Meta-analyses (PRISMA) reporting guidelines. Two authors independently searched the PubMed, Embase, and Cochrane databases for studies relating to the effect of hearing interventions on cognitive decline and dementia in patients with hearing loss.

Main Outcomes and Measures

Maximally adjusted hazard ratios (HRs) were used for dichotomous outcomes and ratio of means for continuous outcomes. Sources of heterogeneity were investigated using sensitivity and subgroup analyses, and publication bias was assessed using visual inspection, the Egger test, and trim and fill.

Results

A total of 3243 studies were screened; 31 studies (25 observational studies, 6 trials) with 137 484 participants were included, of which 19 (15 observational studies, 4 trials) were included in quantitative analyses. Meta-analysis of 8 studies, which had 126 903 participants, had a follow-up duration ranging from 2 to 25 years, and studied long-term associations between hearing aid use and cognitive decline, showed significantly lower hazards of any cognitive decline among hearing aid users compared with participants with uncorrected hearing loss (HR, 0.81; 95% CI, 0.76-0.87; I2 = 0%). Additionally, meta-analysis of 11 studies with 568 participants studying the association between hearing restoration and short-term cognitive test score changes revealed a 3% improvement in short-term cognitive test scores after the use of hearing aids (ratio of means, 1.03; 95% CI, 1.02-1.04, I2 = 0%).

Conclusions and Relevance

In this meta-analysis, the usage of hearing restorative devices by participants with hearing loss was associated with a 19% decrease in hazards of long-term cognitive decline. Furthermore, usage of these devices was significantly associated with a 3% improvement in cognitive test scores that assessed general cognition in the short term. A cognitive benefit of hearing restorative devices should be further investigated in randomized trials.
Search for Alternative Two‐Step‐Absorption Photoinitiators for 3D Laser Nanoprinting
Authors: Bojanowski N. Maximilian , Vranic Aleksandra , Hahn Vincent , Rietz Pascal , Messer Tobias , Brückel Julian , Barner‐Kowollik Christopher , Blasco Eva , Bräse Stefan , Wegener Martin
Published: December 2022

Recent studies have opened the door to a new generation of photoinitiators for 3D laser nanoprinting. Therein, the simultaneous absorption of two photons, commonly referred to as two‐photon absorption, is replaced by the sequential absorption of two photons in two consecutive one‐photon absorption processes. This process has been termed two‐step absorption. Importantly, two‐step absorption can be accomplished by inexpensive compact low‐power continuous‐wave blue laser diodes instead of femtosecond laser systems in the red spectral region. Red‐shifting the second absorption step with respect to the first one results in an and‐type optical nonlinearity based on two‐color two‐step absorption. Herein, alternatives are systematically explored to the few already reported one‐ and two‐color two‐step‐absorption photoinitiators, including the search for photoinitiators that can be excited by one‐color two‐step absorption and be de‐excited by a disparate laser color.
Functional Skeletal Muscle Regeneration Using Muscle Mimetic Tissue Fabricated by Microvalve‐Assisted Coaxial 3D Bioprinting
Authors: Lee Hanna , Kim Soon Hee , Lee Ji Seung , Lee Young Jin , Lee Ok Joo , Ajiteru Olatunji , Sultan Md Tipu , Lee Suk Woo , Park Chan Hum
Published: December 2022

3D‐printed artificial skeletal muscle, which mimics the structural and functional characteristics of native skeletal muscle, is a promising treatment method for muscle reconstruction. Although various fabrication techniques for skeletal muscle using 3D bio‐printers are studied, it is still challenging to build a functional muscle structure. A strategy using microvalve‐assisted coaxial 3D bioprinting in consideration of functional skeletal muscle fabrication is reported. The unit (artificial muscle fascicle: AMF) of muscle mimetic tissue is composed of a core filled with medium‐based C2C12 myoblast aggregates as a role of muscle fibers and a photo cross‐linkable hydrogel‐based shell as a role of connective tissue in muscles that enhances printability and cell adhesion and proliferation. Especially, a microvalve system is applied for the core part with even cell distribution and strong cell–cell interaction. This system enhances myotube formation and consequently shows spontaneous contraction. A multi‐printed AMF (artificial muscle tissue: AMT) as a piece of muscle is implanted into the anterior tibia (TA) muscle defect site of immunocompromised rats. As a result, the TA‐implanted AMT responds to electrical stimulation and represents histologically regenerated muscle tissue. This microvalve‐assisted coaxial 3D bioprinting shows a significant step forward to mimicking native skeletal muscle tissue.
Intrinsic Charge Polarization in Bi19S27Cl3 Nanorods Promotes Selective CC Coupling Reaction during Photoreduction of CO2 to Ethanol
Authors: Das Kousik , Das Risov , Riyaz Mohd , Parui Arko , Bagchi Debabrata , Singh Ashutosh Kumar , Singh Abhishek Kumar , Vinod Chathakudath P. , Peter Sebastian C.
Published: December 2022

Obtaining multi‐carbon products via CO2 photoreduction is a major catalytic challenge involving multielectron‐mediated CC bond formation. Complex design of multicomponent interfaces that are exploited to achieve this chemical transformation, often leads to untraceable deleterious changes in the interfacial chemical environment affecting CO2 conversion efficiency and product selectivity. Alternatively, robust metal centers having asymmetric charge distribution can effectuate CC coupling reaction through the stabilization of intermediates, for desired product selectivity. However, generating inherent charge distribution in a single component catalyst is a difficult material design challenge. Here, a novel photocatalyst, Bi19S27Cl3, is presented which selectively converts CO2 to a C2 product, ethanol, in high yield under visible light irradiation. Structural analysis through transmission electron microscopy, X‐ray diffraction, X‐ray photoelectron spectroscopy, and X‐ray absorption spectroscopy reveals the presence of charge polarized bismuth centers in Bi19S27Cl3. The intrinsic electric field induced by charge polarized bismuth centers renders better separation efficiency of photogenerated electron–hole pair. Furthermore, charge polarized centers yield better adsorption of CO* intermediate and accelerate the rate determining CC coupling step through the formation of OCCOH intermediate. Formation of these intermediates is experimentally mapped by in situ Fourier‐transform infrared spectroscopy and further confirmed by theoretical calculation.
Fully Automated Optimization of Robot‐Based MOF Thin Film Growth via Machine Learning Approaches
Authors: Pilz Lena , Natzeck Carsten , Wohlgemuth Jonas , Scheuermann Nina , Weidler Peter G. , Wagner Ilona , Wöll Christof , Tsotsalas Manuel
Published: December 2022

Metal–organic frameworks (MOFs), have emerged as ideal class of materials for the identification of structure–property relationships and for the targeted design of multifunctional materials for diverse applications. While the powder form is most common, for the integration of MOFs into devices, typically thin films of surface anchored MOFs (SURMOFs), are required. Although the quality of SURMOFs emerging from layer‐by‐layer approaches is impressive, previous works revealed that the optimum growth conditions are very different between different types of MOFs and different substrates. Furthermore, the choice of appropriate synthesis conditions (e.g., solvents, modulators, concentrations, immersion times) is crucial for the growth process and needs to be adjusted for different substrates. Machine learning (ML) approaches show great promise for multi‐parameter optimization problems such as the above discussed growth conditions for SURMOF on a particular substrate. Here, this work presents an ML‐based approach allowing to quickly identify optimized growth conditions for HKUST‐I SURMOFs with high crystallinity and uniform orientation. This process can subsequently be used to optimize growth on other types of substrates. In addition, an analysis of the results allows to gain further insights into the factors governing the growth of MOF thin films.
Reinforcement of Bonding Strength between Dental Y‐TZP and Resin via Nano‐Thin and Conformal SiO2 Films by Atomic Layer Deposition
Authors: Yan Yuxin , Shu Fei , Chen Hong , Dun Zhiyue , Lv Weijin , Zhang Zhihao , Sun Wangxinyue , Liu Mei
Published: December 2022

The retentive strength of zirconia crowns is derived from resin cement, and the weak interface between the two is the main reason for their failure. In this work, nano‐thin silica (SiO2) films of precisely controlled thickness are deposited over yttrium‐stabilized tetragonal zirconia polycrystal (Y‐TZP) ceramics via atomic layer deposition (ALD). The deposited films are modified using a silane coupling agent, which significantly improves the bonding strength between Y‐TZP and resin. Scanning electron microscopy shows that the SiO2 films deposited by ALD are uniform and can accurately maintain the morphology of grit‐blasted Y‐TZP. Spectroscopic ellipsometry demonstrates that the films are nano‐thin, with thicknesses in the range of 5.58–26.58 nm. The increase in the shear bond strength is attributed to the chemical bonding between the conformal nano‐SiO2 films and Y‐TZP. However, the stability of the bond decreases when the SiO2 films are too thick. Overall, the results indicate that SiO2 films deposited in 400 ALD cycles have both good bonding strength and stability after aging, much higher than those of Z‐Prime Plus films.
Photo‐Assisted Barrier Effect for Improving the Sensing Performance to Copper Ions
Authors: Liang Zhensen , Ma Ye , Wang Xiaoming , He Yichang , Liao Yiquan , Zhang Bin , Zhao Minggang , Cui Hongzhi
Published: December 2022

Copper ions (Cu2+) pollution poses a serious threat to Marine ecology and fisheries, but the online detection is difficult due to seawater interference. Herein, photo‐assisted barrier effect is introduced into electrochemical detection as a driver to generate electrochemical response. The n–n junction barrier exhibits excellent adjusting effect on electrochemical response under photoexcitation and could effectively drive electrochemical response by Cu2+ adsorption. The prepared Ti/TiO2/In2O3/Chitosan wire is used for direct Cu2+ detection, and the trace detection with the low detection limit (59.08 nm) is achieved. The strong interference of seawater is resisted effectively by using photo‐assisted barrier effect, and the good recovery rate (94.9–107.1%) in the actual seawater detection make it promising for practical applications. It is a new approach to develop electrochemical sensors by using photo‐assisted barrier effect to resist interference.
Effects of Energy‐Level Alignment on Operating Voltages of Blue Organic Light‐Emitting Diodes
Authors: Sasaki Tsubasa , Oono Taku , Shimizu Takahisa , Fukagawa Hirohiko
Published: December 2022

Although organic light‐emitting diodes (OLEDs) have been studied extensively for various applications, the effect of the electron behavior on the characteristics of OLEDs has rarely been discussed owing to the difficulty in investigating the actual energy levels. Understanding the correlation between energy levels and the characteristics of OLEDs is essential to improve the performances of blue OLEDs, since the materials with relatively large band gaps used in blue OLEDs make it difficult to deliver electrons from the cathode to the emitting layer (EML). Here, it is shown that the operating voltages of blue OLEDs strongly depend on the energy barrier between the cathode and the EML, which is clarified by investigating the energy‐level alignment in blue OLEDs. It is found that a blue OLED fabricated using a superbase as the electron injection layer exhibits a lower operating voltage than conventional blue OLEDs fabricated using Li compounds. Moreover, there is a clear energy barrier between the cathode and the EML in conventional blue OLEDs, whereas there is no energy barrier in blue OLEDs fabricated using a superbase. Minimization of the energy barrier between the cathode and the EML is demonstrated to be essential to obtain blue emission at low operating voltages.
EMSCs‐Seeded Micro‐Stripe Patterned Polycaprolactone Promoting Sciatic Nerve Regeneration
Authors: Lu Naiyan , Wang Xinhe , Li Xu , Shi Wentao , Wang Xun , Zou Yin , Yang Guofeng , Tang Xue , Zhang Zhijian , Xiang Wen , Weng Yuyan
Published: December 2022

Transplantation of a synthetic polymer nerve conduit carrying stem cells is promising for treating peripheral nerve injury. In this study, a micropatterned inner surface of polycaprolactone (PCL) nerve conduit cellularized with nasal respiratory mucosa‐derived ectoderm mesenchymal stem cells (EMSCs) is adopted for peripheral nerve regeneration. The PCL microstructure grating is fabricated by soft nanoimprint lithography (NIL), whose templates can be easily transferred from the Ebeam photoresist pattern. The most suitable microstructure is carefully chosen to support EMSCs alignment and nerve regeneration. In vitro, the micropatterned PCL nerve conduit greatly enhanced the directional alignment of EMSCs and the MBP and S100 expression of myelin proteins. Additionally, the micropatterned conduit preseeded with EMSCs significantly stimulated the axon‐directed extension of neural stem cells. In vivo, micropatterned PCL conduits cotransplanted with EMSCs enhanced motor function and promoted sciatic nerve regeneration and extension in a rat model of sciatic nerve defect. Taken together, this “all‐in‐one” nerve guidance conduit makes sciatic nerve regeneration and morphological repairing accelerated, which has a potential clinical application in neural tissue engineering.
Enhanced Laplace Pressures for Functional Surfaces: Wicking, Switchability, and Selectivity
Authors: Wilke Kyle L. , Song Youngsup , Lu Zhengmao , Wang Evelyn N.
Published: December 2022

Wetting functionalities of rough surfaces are largely determined by the Laplace pressure generated across liquid–gas interfaces formed within surface structures. Typically, rough wetting surfaces create negative Laplace pressures, enabling capillary wicking, while rough non‐wetting surfaces create positive Laplace pressures, exhibiting fluid repellency. Here, with microfabricated reentrant structures, it is shown that the same surface can exhibit either a negative or positive Laplace pressure, regardless of its intrinsic wettability. This material‐independent Laplace pressure duality enables or enhances a range of wetting functionalities including wicking, switchability, and selectivity. On the same surface, capillary rise, capillary dip, and the combination of the two which leads to further enhancement of the total sustainable capillary height and Laplace pressure, the driving force for wicking is demonstrated. Further, active switching of wetting states between the hemiwicking and the repellent Cassie state on reentrant structures is shown. Moreover, with a water‐hexane mixture system, selective wetting of reentrant structures are demonstrated, that is, water can be selectively wicked or repelled in the presence of hexane, and vice versa. These functionalities are achieved, which would typically require complex chemical coatings, solely using surface structures, thus largely expanding the design space for a wide range of thermofluidic applications.
Laccase‐Triggered Surface Co‐Deposition of Gentisic Acid and Chitosan for Multifunctional Polymer Membranes
Authors: Yang Wen‐Ying , Zhou Di , Shen Jia‐Lu , Xu Zhi‐Kang , Wan Ling‐Shu
Published: December 2022

Co‐deposition of phenols and amines inspired by mussel‐inspired chemistry has attracted much attention in the field of surface and interface science and technology. However, most deposition systems are still limited to phenols with at least one catechol group. In this work, a novel enzyme‐triggered co‐deposition system based on a natural phenol (gentisic acid, GA) and a kind of biomacromolecule (chitosan, CS) is reported. With the catalysis of laccase, GA can be oxidized and further react with CS to form effective surface coatings on various substrates such as polypropylene microfiltration membrane (PPMM). The co‐deposition process takes only 40 min at room temperature and endows the membrane with superhydrophilicity and underwater superoleophobicity. The modified membranes show excellent separation performance, reusability, and long‐term stability for the separation of oil‐in‐water emulsions. The modified membranes are highly charged (pI ≈7.2) and capable of efficient dye adsorption. In addition, the modified membranes possess better protein resistance properties compared with the nascent membranes. This work demonstrates a green, mild, and highly efficient surface modification process based on laccase catalysis. The co‐deposition system comes from natural sources and expands the phenol family for constructing multi‐functional surface coatings.
Transparent, Stretchable, and Self‐Healable Gas Barrier Films with 2D Nanoplatelets for Flexible Electronic Device Packaging Applications
Authors: Mahmood Sadiq , Khan Amir , Kant Chandra , Chu Chih Wei , Katiyar Monica , Lin Hong‐Cheu
Published: December 2022

Self‐healable elastomeric materials (PUAxPU10–x‐PDMS, x = 4, 6, or 8) have been synthesized and utilized as substrates or encapsulation films on the top of barrier films (deposited on polyethylene terephthalate (PET) substrates) to improve their gas barrier properties for packaging applications. Hexa‐layer (HL) assembly consisting of two inorganic 2D nanoplatelets, including Mg‐Al layered double hydroxide (LDH) and hexagonal boron nitride (hBN), and two oppositely charged polyelectrolytes, that is, polyethyleneimine (PEI) and poly(sodium styrene‐4‐sulfonate) (PSS), have been developed by alternative depositions of HL (i.e., PSS/LDH/PSS/PEI/hBN/PEI) sequentially. Then, a layer‐by‐layer technique is applied to produce multiple assemblies of hexa‐layer (HL)n and reduce water vapor transmission rate (WVTR) values of elastomeric PUA8PU2‐PDMS and PET substrates. The optimum WVTR values of 7.1 × 10−3 and 8.0 × 10−3 g m−2 day−1 are achieved using barrier PET/(HL)8/PUA8PU2‐PDMS (125/3/1 µm) and PUA8PU2‐PDMS/(HL)8 (125/3 µm) films, respectively. The self‐healable barrier PUA8PU2‐PDMS and PUA8PU2‐PDMS/(HL)8 films recover their initial WVTR values after self‐healing of mechanically damaged films. Organic light‐emitting diodes (OLEDs) encapsulated with PET/(HL)8/PUA8PU2‐PDMS and PUA8PU2‐PDMS/(HL)8 have 9–10 times longer half‐lifetime values than bare OLEDs. Accordingly, this report develops transparent, stretchable, and self‐healable gas barrier films for next‐generation flexible electronic device packaging applications.
Implementation of Tunneling Junction Passivated Contact Concept in Flexible CIGS Solar Cells
Authors: Chang Xuan , Chen Jingwei , Ma Shuangyi , Chen Bingbing , Zhang Xuning , Gao Qing , Li Feng , Wang Jianming , Song Dengyuan , Chen Jianhui
Published: December 2022

In today's state‐of‐the‐art high‐efficiency silicon solar cells need to be inserted a thin insulating layer in order to reduce the recombination losses between the carrier transport layer and Si surface, which can form a tunneling junction (TJ), thus increasing the performance of the TJ solar cells comparable with the pn junction structure. However, the copper indium gallium selenium (CIGS) solar cells inevitably lead to the losses of the carrier transport due to the interface which is widely assumed as the pn‐heterojunction. Herein, the TJ solar cells, aiming to enhance the performance of the solar cells, are fabricated by inserting the TiO2 between CIGS/CdS interface deposited by atomic layer deposition (ALD). By inserting the TiO2 insulating layer, the CIGS/TiO2/CdS structure can be effectively reduced the interface recombination, which leads to a reduced band bending in the p‐CIGS surface and compromises its field‐effect passivation. As a result, the CIGS solar cell with the tunneling junction achieves the 15.57% based on the stainless steel (SS) substrate, by introducing a barrier layer and doping NaF. These results provide an important preliminary foundation for the development of the CIGS solar cells with the tunneling junction structure.
Triple‐Asymmetric Flexible Strain Sensor Based on High‐aligned Ni Nanowire Arrays with Opposite Resistance Responding for Multidimensional Motions Detection
Authors: Huang Xiaowei , Xiang Wenfeng , Li Chenghan , Guo Meng , Zhang Guorong , Huang Yu , Liu Yu , Yang Weiqiang , Wang Caoye
Published: December 2022

Herein, a triple‐asymmetric flexible strain sensor by using the single‐layered high‐aligned Ni‐nanowire arrays is proposed for the applications of monitoring multidimensional motions of human joints. The triple‐asymmetric structures consist of a spatially ordering distribution of Ni nanowires (NWs) and double position asymmetric distributions of the Ni NWs in width and thickness direction of sensor. Because Ni NWs are isolated from each other, the resistance change of the sensor is by tunneling effect. The resistance values of the proposed sensor decrease with the increasing of stretching strain, which is different from that of the common flexible strain sensors, and the maximum absolute valve of gauge factor is 35. Furthermore, the proposed sensor has a good bending sensitivity, ranging from 90° to −90°, and minimum resolution angle of 5° in out‐plane bending. Benefiting from the asymmetric structures and tunneling effect, the complex movements of human joints (such as up‐down bending, left‐right swing, and rotating of wrist) are successfully detected. The practical applicability in real‐time monitoring and the processes of handwriting are also shown. Therefore, this proposed sensor is believed to have great potential in future development of micro‐motion monitoring, wearable electronics, and artificial intelligence.
Nanobridge Stencil Enabling High Resolution Arbitrarily Shaped Metallic Thin Films on Various Substrates
Authors: Sun Yi‐Chiang , Boero Giovanni , Brugger Jürgen
Published: December 2022

Stencil lithography (SL), which uses a perforated membrane as a reusable shadow mask to locally add material patterns on substrates provides a simple but versatile approach for the fabrication of functional devices on a large variety of substrate materials by physical vapor deposition (PVD). Mechanical stress induced by the accumulation of condensed material on the thin stencil membrane during the PVD step leads to stencil bending and breaking, therefore, suspended stencil membranes with arbitrary openings are, in practice, not possible. Here, a new approach to remedy this limitation is reported by introducing auxiliary bridges in stencils. These bridges prevent the suspended membrane from bending out of plane, thereby enabling aperture openings to have almost arbitrary geometry. These bridges are sufficiently narrow so that they do not entirely block the material deposition by PVD and thus create a continuous material pattern by taking advantage of the blurring effect. The successful metal deposition through the designed nanobridge stencil on a wide range of substrate materials underlines the usability and the versatility of the proposed stencil design. The work presented here provides a versatile fabrication method to produce arbitrarily shaped metal patterns that were previously impossible due to the topological constraints of nanostencils.
High Molecular Weight Fucoidan Loading Into and Release from Hyaluronate‐Based Prefabricated Hydrogel and its Nanogel Particles Controlled by Variable Pitch and Differential Extensional Shear Technology of Advanced Twin Screw‐Based System
Authors: Khatun Mst Rita , Bhattacharyya Amitava , Taheri Shiva , Ham Hyeong‐wook , Kim Hongkyun , Chang Seok Hong , Noh Insup
Published: December 2022

Efficient incorporation of high molecular weight drug into prefabricated hydrogel and its delivery are big challenges in its applications to drug delivery and tissue regeneration using a 3D bioprinting system. In this work, a new method of loading a model high molecular weight drug (fucoidan with 200 kDa) into prefabricated hyaluronate‐based terpolymeric gel is developed by using an advanced screw‐based extrusion printing system. This system effectively incorporates the fucoidan biomolecules into the prefabricated crosslinked gel within 60 s at significantly higher percentages without much change in gel properties. Less damage in gel network is achieved through variable pitch and differential extensional shear mechanism by optimization of bioprinting conditions. Importantly, fucoidan‐loaded nanoparticles (NPs) are developed using the advanced extrusion system at high screw rpm and with increased residence time using recirculation. The encapsulation efficiency, sustained release of fucoidan, and in vitro cell culture studies confirm the nontoxic nature of the drug‐loaded gels and nanogels at lower doses, exhibiting the biomedical application potentials of this advanced screw‐based extrusion printing system and drug‐loaded NPs formation in pharmaceuticals, 3D bioprinting, tissue engineering as well as maximal drug loading into and sustained release from prefabricated gels.
Enhancing the Reaction Kinetics and Reversibility of Li–O2 Batteries by Multifunctional Polymer Additive
Authors: Wu Xiaohong , Niu Ben , Zhang Haitang , Li Zhengang , Luo Haiyan , Tang Yonglin , Yu Xiaoyu , Huang Ling , He Xianru , Wang Xin , Qiao Yu , Sun Shi‐Gang
Published: December 2022

As a potential candidate for next‐generation energy storage systems, Li–O2 batteries (LOBs) with their attractive theoretical energy density have triggered great interest. However, tough issues of sluggish oxygen reduction reaction/oxygen evolution reaction (ORR/OER) kinetics, poor rechargeability, superoxide‐derived side reactions, and Li‐metal corrosion in LOBs limit their practical applications. Herein, a poly(2,2,2‐trifluoroethyl methacrylate) (PTFEMA) additive is introduced into the typical electrolyte, giving superior cycling performance to LOBs. Enabling strong solvation of Li+, PTFEMA regulates a uniform Li+ flow at the cathode and anode sides of LOBs. Induced by homogeneous Li+ flux and favorable adsorption with superoxide species, PTFEMA promotes superoxide transformation in the ORR and inhibits superoxide‐induced parasitic reactions. Uniform Li+ flux gives evenly‐distributed Li2O2 that can be completely decomposed during OER. In addition, PTFEMA protects Li‐metal against corrosion from O2, superoxide, and byproducts shuttle. Hence, accelerated ORR/OER kinetics, facilitated rechargeability, suppressed superoxide‐derived side reactions, and well‐protected Li‐metal can be simultaneously realized with PTFEMA, resulting in significantly enhanced electrochemical performance of LOBs. This electrolyte engineering involving facile multifunctional polymer additives provides a practical alternative to complex componential optimization toward commercial LOBs and gives insight to the understanding of uniform Li+ flux on reaction kinetics and reversibility.
Impact of Reversible Proton Insertion on the Electrochemistry of Electrode Materials Operating in Mild Aqueous Electrolytes: A Case Study with TiO2
Authors: Makivić Nikolina , Harris Kenneth D. , Tarascon Jean‐Marie , Limoges Benoît , Balland Véronique
Published: December 2022

Near‐neutral aqueous electrolytes are to be preferred for the development of sustainable electrochemical energy conversion and storage devices. Protons are inherent to these electrolytes and their reactivity toward the electrode material extends beyond their own reduction, especially when reversible proton insertion takes place in the bulk electrode material from acidic or buffered electrolytes. However, a still burning question is regarding whether reversible proton insertion persists when working in unbuffered mild aqueous electrolytes, and if so, with which consequences on the functioning of the electrode material. Here this issue is addressed by examining TiO2 as a model insertion electrode in a range of mild aqueous electrolytes. Through a combination of experiments, modelling and multiphysics simulations, it is demonstrated that in a KCl‐based electrolyte, water acts as proton donor to support the reversible insertion of protons in TiO2, while in a NH4Cl‐based aqueous electrolyte, the proton donor is NH4+. Moreover, it is established that strong pH gradients develop at the electrode interface during proton insertion/disinsertion, highlighting their dependence on the proton donor/acceptor and rationalizing their impact on the electrode voltage. Overall, this work provides a comprehensive framework of proton‐insertion coupled electron transfer that can be easily generalized to other electrode materials.
Plant‐Derived l‐Theanine for Ultraviolet/Ozone Resistant Perovskite Photovoltaics
Authors: Li Yong , Liu Lidan , Zheng Can , Liu Zhike , Chen Li , Yuan Ningyi , Ding Jianning , Wang Dapeng , Liu Shengzhong (Frank)
Published: December 2022

As the efficiency of perovskite solar cell has skyrocketed to as high as 25.7%, their stability has become the biggest obstacle to commercialization. Preliminary analyses suggest that additive engineering may be effective in improving both solar cell efficiency and its stability. Herein, the plant‐derived natural green additive of l‐Theanine (Thea) is selected to improve the crystal quality of the perovskite absorber and obtain high‐performance perovskite solar cells (PSCs) with ultraviolet/ozone (UV/O3) resistance. The characterization results reveal that the CO group in Thea can effectively inhibit the precipitation of metal Pb0, passivate undercoordinated Pb2+ ions, and promote the nucleation and crystallization of perovskite. In addition, the combination of the NH group and I− in the form of a hydrogen bond cooperatively reduce the probability of nonradiative recombination of photogenerated carriers and effectively improves the extraction ability of carriers from perovskite absorber. With the cooperation of CO and NH2 groups in Thea, the champion efficiency is improved from 22.29% in the control device to 24.58%. More importantly, Thea significantly alleviates the perovskite phase transition and film decomposition induced by UV/O3 treatment. The study provides exploratory research for the application of plant‐derived green additives in the UV/O3 resistance field of perovskite photovoltaics.
Efficacy of a single‐day task trainer–based extracorporeal membrane oxygenation training course
Authors: Maddry Joseph K. , Paredes R. Madelaine , Abdurashidov Timur , Davis William T. , Paciocco Joni A. , Castaneda Maria , Araña Allyson A. , Perez Crystal A. , Baldwin Darren S. , Rodriguez Dylan C. , Medellin Kimberly L. , Ng Patrick
Published: December 2022

Background

Extracorporeal membrane oxygenation (ECMO) is an advanced medical technology used to treat respiratory and heart failure. The coronavirus pandemic has resulted in significantly more ECMO patients worldwide. However, the number of hospitals with ECMO capabilities and ECMO‐trained staff are limited. Training of personnel in ECMO could supplement this demand.

Objective

To evaluate our previously developed ECMO course using a task trainer–based training, as opposed to an existing live tissue–training model, and determine if such a program was adequate and could be expanded to other facilities.

Methods

Seventeen teams, each consisting of a physician and nurse, underwent a 5 hour accelerated ECMO course in which they watched prerecorded ECMO training lectures, primed circuit, cannulated, initiated ECMO, and corrected common complications. Training success was evaluated via knowledge and confidence assessments and observation of each team attempting to initiate ECMO while troubleshooting complications on a Yorkshire swine.

Results

Seventeen teams successfully completed the course. Sixteen teams (94%, 95% CI = 71%–100%) successfully placed the swine on veno‐arterial ECMO. Of those 16 teams, 15 successfully transitioned to veno‐arterial–venous ECMO. The knowledge assessments and confidence levels of physicians and nurses increased by 24.3% from pretest (mean of 65.3%, SD 14.4%) to posttest (mean of 89.6%, SD 10.3%), p < 0.0001.

Conclusions

An abbreviated one day lecture and hands‐on task trainer–based ECMO course resulted in a high rate of successful skill demonstration and improvement of physicians' and nurses' knowledge assessments and confidence levels, similar to our previous live tissue training program.
Approaches to engage an aging, rural cohort in southern India during the COVID‐19 crisis and the psychological impact of COVID‐19 in this cohort
Authors: Sundarakumar Jonas S. , Hameed Shafeeq K.S. , Dilip Babu , Deepak Shylashree , Kumar B.R. Vinay , Ravindranath Vijayalakshmi
Published: December 2022

Introduction

The COVID‐19 pandemic produced an unprecedented crisis across the world. Long‐term cohort studies were stalled, including our longitudinal aging cohort study in rural India.

Methods

We describe approaches undertaken to engage with our cohort (n = 1830) through multiple rounds of calls and how we provided useful services to our subjects during the lockdown period. Consenting subjects also underwent telephonic assessments for depression and anxiety using validated, self‐report questionnaires.

Results

Subjects reported benefitting from our telephonic engagement strategies, including the COVID‐related safety awareness and counselling service. The proportion of subjects with depression increased from 7.42% pre‐COVID to 28.97% post‐COVID.

Discussion

We envisage that such engagement strategies would improve subject rapport and cohort retention, and thus, could be adopted by similar cohort studies across the world. This marginalized, rural Indian community had severe, adverse psychological impact in this pandemic. Urgent public health measures are needed to mitigate this impact and develop appropriate preventive strategies.
MOFs with Open Metal(III) Sites for the Environmental Capture of Polar Volatile Organic Compounds
Authors: Severino Maria Inês , Al Mohtar Abeer , Vieira Soares Carla , Freitas Cátia , Sadovnik Nicolas , Nandi Shyamapada , Mouchaham Georges , Pimenta Vanessa , Nouar Farid , Daturi Marco , Maurin Guillaume , Pinto Moisés L. , Serre Christian
Published: December 2022

Metal–Organic Frameworks (MOFs) with open metal sites (OMS) interact strongly with a range of polar gases/vapors. However, under ambient conditions, their selective adsorption is generally impaired due to a high OMS affinity to water. This led previously to the privilege selection of hydrophobic MOFs for the selective capture/detection of volatile organic compounds (VOCs). Herein, we show that this paradigm is challenged by metal(III) polycarboxylates MOFs, bearing a high concentration of OMS, as MIL‐100(Fe), enabling the selective capture of polar VOCs even in the presence of water. With experimental and computational tools, including single‐component gravimetric and dynamic mixture adsorption measurements, in situ infrared (IR) spectroscopy and Density Functional Theory calculations we reveal that this adsorption mechanism involves a direct coordination of the VOC on the OMS, associated with an interaction energy that exceeds that of water. Hence, MOFs with OMS are demonstrated to be of interest for air purification purposes.
Aerobe C‐N‐Bindungsknüpfung durch enzymatische Nitroso‐En‐Reaktionen**
Authors: Jäger Christina , Haase Mona , Koschorreck Katja , Urlacher Vlada B. , Deska Jan
Published: December 2022

Die biokatalytische Oxidation acylierter Hydroxylamine ermöglicht die direkte und selektive Einführung Stickstoff‐haltiger funktioneller Gruppen durch Aktivierung allylischer C‐H‐Bindungen. Durch Verwendung von entweder Laccasen oder einem Enzympaar aus Oxidase und Peroxidase mit Luft als terminalem Oxidationsmittel erfolgt die formale Dehydrierung von N‐Hydroxycarbamaten und Hydroxamsäuren, wodurch unter überaus milden Reaktionsbedingungen Acylnitroso‐Intermediate gebildet werden können. Über einen Alder‐En‐Mechanismus gehen diese reaktiven Zwischenstufen C‐N‐Bindungsknüpfungen ein und sowohl intra‐ als auch intermolekulare enzymatische Aminierungen gelingen in hohen Ausbeuten. Untersuchungen zu Gemeinsamkeiten und Unterschieden der beiden Enzymsysteme in Bezug auf Stereoselektivitäten wie auch Isotopenmarkierungsexperimente liefern neue Einblicke in das promiske Verhalten der Oxidoreduktasen und Grundlagen für die Weiterentwicklung als Katalysatoren in nicht‐nativen Transformationen.
Intelligente elektrochemische Rasterzellmikroskopie für den Nachweis schneller Li‐Ionen‐Speicherung und Dynamik in TiO2‐Nanopartikeln
Authors: Tetteh Emmanuel Batsa , Valavanis Dimitrios , Daviddi Enrico , Xu Xiangdong , Santana Santos Carla , Ventosa Edgar , Martín‐Yerga Daniel , Schuhmann Wolfgang , Unwin Patrick R.
Published: December 2022

Anatas‐TiO2 ist ein vielversprechendes Material für Li‐Ionen‐Batterien (Li+) mit Schnellladefähigkeit. Die (De‐)Interkalationsdynamik von Li+ in TiO2 ist jedoch nach wie vor schwer fassbar, und die beschriebenen Diffusivitäten überspannen viele Größenordnungen. Wir entwickeln ein intelligentes Protokoll für die rasterelektrochemische Zellmikroskopie (SECCM) in Kombination mit in situ optischer Mikroskopie (OM), um die Lade‐/Entladeanalyse einzelner TiO2‐Nanopartikel‐Cluster mit hohem Durchsatz zu beobachten. Die direkte Untersuchung aktiver Nanopartikel ergab, dass TiO2 mit einer Größe von ca. 50 nm mehr als 30 % der theoretischen Kapazität bei einer äußerst schnellen Lade‐/Entladerate von ca. 100 C speichern kann. Dieser Nachweis einer schnellen Li+‐Speicherung in TiO2‐Partikeln stärkt ihr Potenzial für schnell ladende Batterien. Die hier vorgeschlagene SECCM‐OM ist generell für das elektrochemische Hochdurchsatz‐Screening von nanostrukturierten Materialien breit anwendbar.
An Organic Molecular Nanobarrel that Hosts and Solubilizes C60
Authors: Bera Saibal , Das Satyajit , Melle‐Franco Manuel , Mateo‐Alonso Aurelio
Published: December 2022

Organic cages have gained increasing attention in recent years as molecular hosts and porous materials. Among these, barrel‐shaped cages or molecular nanobarrels are promising systems to encapsulate large hosts as they possess windows of the same size as their internal cavity. However, these systems have received little attention and remain practically unexplored despite their potential. Herein, we report the design and synthesis of a new trigonal prismatic organic nanobarrel with two large triangular windows with a diameter of 12.7 Å optimal for the encapsulation of C60. Remarkably, this organic nanobarrel shows a high affinity for C60in solvents in which C60is virtually insoluble, providing stable solutions of C60.
Iron Nanoparticles Protected by Chainmail‐structured Graphene for Durable Electrocatalytic Nitrate Reduction to Nitrogen
Authors: Zhang Hui , Wang Chuqi , Luo Hongxia , Chen Junliang , Kuang Min , Yang Jianping
Published: December 2022

The electrochemical nitrate reduction reaction (NO3RR) is an appealing technology for regulating the nitrogen cycle. Metallic iron is one of the well‐known electrocatalysts for NO3RR, but it suffers from poor durability due to leaching and oxidation of iron during the electrocatalytic process. In this work, a graphene‐nanochainmail‐protected iron nanoparticle (Fe@Gnc) electrocatalyst is reported. It displays superior nitrate removal efficiency and high nitrogen selectivity. Notably, the catalyst delivers exceptional stability and durability, with the nitrate removal rate and nitrogen selectivity remained ≈96 % of that of the first time after up to 40 cycles (24 h for one cycle). As expected, the conductive graphene nanochainmail provides robust protection for the internal iron active sites, allowing Fe@Gnc to maintain its long‐lasting electrochemical nitrate catalytic activity. This research proposes a workable solution for the scientific challenge of poor lasting ability of iron‐based electrocatalysts in large‐scale industrialization.
Caught in Action: Visualizing Dynamic Nanostructures Within Supramolecular Systems Chemistry
Authors: Venugopal Akhil , Ruiz‐Perez Lorena , Swamynathan K. , Kulkarni Chidambar , Calò Annalisa , Kumar Mohit
Published: December 2022

Supramolecular systems chemistry has been an area of active research to develop nanomaterials with life‐like functions. Progress in systems chemistry relies on our ability to probe the nanostructure formation in solution. Often visualizing the dynamics of nanostructures which transform over time is a formidable challenge. This necessitates a paradigm shift from dry sample imaging towards solution‐based techniques. We review the application of state‐of‐the‐art techniques for real‐time, in situ visualization of dynamic self‐assembly processes. We present how solution‐based techniques namely optical super‐resolution microscopy, solution‐state atomic force microscopy, liquid‐phase transmission electron microscopy, molecular dynamics simulations and other emerging techniques are revolutionizing our understanding of active and adaptive nanomaterials with life‐like functions. This Review provides the visualization toolbox and futuristic vision to tap the potential of dynamic nanomaterials.
Fast Li‐ion Storage and Dynamics in TiO2 Nanoparticle Clusters Probed by Smart Scanning Electrochemical Cell Microscopy
Authors: Tetteh Emmanuel Batsa , Valavanis Dimitrios , Daviddi Enrico , Xu Xiangdong , Santana Santos Carla , Ventosa Edgar , Martín‐Yerga Daniel , Schuhmann Wolfgang , Unwin Patrick R.
Published: December 2022

Anatase TiO2 is a promising material for Li‐ion (Li+) batteries with fast charging capability. However, Li+ (de)intercalation dynamics in TiO2 remain elusive and reported diffusivities span many orders of magnitude. Here, we develop a smart protocol for scanning electrochemical cell microscopy (SECCM) with in situ optical microscopy (OM) to enable the high‐throughput charge/discharge analysis of single TiO2 nanoparticle clusters. Directly probing active nanoparticles revealed that TiO2 with a size of ≈50 nm can store over 30 % of the theoretical capacity at an extremely fast charge/discharge rate of ≈100 C. This finding of fast Li+ storage in TiO2 particles strengthens its potential for fast‐charging batteries. More generally, smart SECCM‐OM should find wide applications for high‐throughput electrochemical screening of nanostructured materials.
Adsorption decolorization and composition analysis of high melting point Fischer–Tropsch waxes
Authors: Jiang Chenguang , Zhang Shengzhen , Zhang Cuiqing , Li Xiaofeng , Guo Yi
Published: December 2022

The decolorization and quality improvement of the high melting point Fischer–Tropsch wax were carried out by the method of adsorption refining, and the activated clay was selected as adsorbent. The effects of adsorption decolorization temperature on the wax products were evaluated by testing the saybolt color number and whiteness value of the waxes. Meanwhile, the influence of adsorption decolorization temperature on the composition of waxes was investigated by gas chromatography (GC), inductively coupled plasma (ICP), thermogravimetry/differential thermogravimetry (TG/DTG), differential scanning calorimetry (DSC), thermogravimetric mass spectrometry (TG‐MS), Fourier transform infrared (FTIR), nuclear magnetic resonance (NMR), scanning electron microscopy (SEM), and X‐ray fluorescence (XRF) characterizations of waxes and adsorbents activated clay before and after use. The results showed that the best adsorption decolorization temperature is 120°C, and the corresponding saybolt color number of decolorization waxes is +16. The reasons for the poor chromaticity of high melting point wax are not only the inorganic components mainly composed of residual ultrafine catalyst particles but also the organic components of unsaturated carbon–carbon double bonds and heteroatomic compounds containing oxygen, nitrogen, and sulfur. The oxidative deterioration of the unsaturated carbon–carbon double bond and hydrocarbons with low bond energy in waxes, as well as the oxidation of hydrocarbons containing oxygen and nitrogen heteroatoms, may be the main reasons for the yellowing of the wax products in the process of decolorization.