bluuebunny/crossref_metadata_2025 huggingface dataset:
Investigating Female Costumer’s Impulse Buying in Facebook B2C Social Commerce: An Experimental Study
Authors: Chen Jengchung Victor , Chotimapruek Waranuch , Ha Quang-An , Widjaja Andree E.
Published: August 2021

Along with the popularity of social network site, social commerce such as Facebook has rapidly become a promising platform to conduct online advertisings and business activities. Drawing from Latent State Trait theory (LST), we conducted an online experiment to empirically investigate the impact of information quality, picture of product presentation, the number of people’s “Like”, and impulsiveness on female customer’s urge to buy impulsively as well as the interaction effect of environmental cues and individual trait. The results showed that information quality, picture of product presentation, impulsiveness positively affected urge to buy impulsively. Contrary to our expectation, only information quality was found to interact with impulsiveness to jointly influence impulsive buying behavior, while the interaction of impulsiveness with product presentation and the number of like was insignificant. The findings not only help to enrich our understanding about important factors influencing impulse buying within Facebook B2C social commerce but also offer social commerce practitioners better strategy in selling their products and services, specifically for female customers.
Analysis of Factors influencing Impulse Buying behavior towards e-tailing sites: An application of S-O-R model
Authors: Karim Md Wasiul , Chowdhury Mohammad Abdul Matin , Masud Md Abdullah Al , Arifuzzaman Md.
Published: August 2021

Impulse buying behavior among consumers was previously examined within the brick-and-mortar stores. The internet revolution is the shift from a traditional retail environment to electronic commerce where products and services are offered online and consumers benefit from buying impulse towards e-tailing sites. By applying the S-O-R model, this study seeks to evidently identify the influencing factors of impulse buying behavior towards e-tailing sites. The survey data were analyzed using partial least squares structural equation modeling (PLS-SEM). The result indicates that website stimulus has no significant positive relationship with online impulsive buying behavior, but an indirect relationship is found to be associated with impulse buying behavior. Results also highlighted that website stimulus, marketing stimulus, and product variety positively influence perceived enjoyment, where perceived enjoyment was a strong predictor of online impulse buying behavior. The study contributes to the existing literature by employing external stimuli of the research framework. It was thus recommended to the online e-tailers to maximize their relationship with consumers by providing valuable products and services through online platforms.
Long‐Term Observation of Locomotion of Drosophila Larvae Facilitates Feasibility of Food‐Choice Assays
Authors: Bittern Jonas , Praetz Marit , Baldenius Marie , Klämbt Christian
Published: August 2021

Animal behavior is reflected by locomotor patterns. To decipher the underlying neural circuitry locomotion has to be monitored over often longer time periods. Here a simple adaptation is described to constrain movement of third instar Drosophila larvae to a defined area and use Frustrated total internal reflection based imaging method (FIM) imaging to monitor larval movements up to 1 h. It is demonstrated that the combination of FIM imaging and long analysis periods facilitates the conduction of food choice assays and provides the means to easily quantify food preferences.
Study on the Magnetic Field‐Dependent Rolling Friction Coefficient Compensation of Magnetorheological Elastomer–Copper Ball Friction Pair with Wet Interfaces
Authors: Li Rui , Gou Xin , Li Xinyan , Yang Ping-an , Feng Dan , Tang Xianlun
Published: August 2021

Inline noncontact compensation of the declining rolling friction coefficient (f
r) of rolling rotating equipment in contaminated conditions is still a challenge. Herein, it is verified that f
r of magnetorheological elastomers (MREs) under common industrial pollution can be real‐time contactless compensation by magnetic field. Experimental results show that the MRE–copper ball friction pair in water medium has the best effect of magnetic field induction linear compensation, whose nonlinear error is only 1.93%. Particularly, the magnetic field‐induced f
r of MRE coated with water can compensate to 95% of that of dry surface without magnetic field (K
0) at magnetic field of 50 mT. And even‐coated edible blended oil or engine oil surface, f
r can be compensated by 90% of K
0 at 150 mT. The mechanism of magnetic field‐induced rolling friction compensation is that the magnetic field causes the MRE to become hard and partially rough, thereby increasing the f
r; water has the smallest apparent viscosity, leading to an optimal compensation effect. It is considered that water is a common pollutant in the industry and has excellent heat dissipation properties. It is anticipated that this research provides a method of linear contactless compensation, f
r, and improves the service life of the equipment.
Band Edge Control of Quasi‐2D Metal Halide Perovskites for Blue Light‐Emitting Diodes with Enhanced Performance
Authors: Worku Michael , Ben‐Akacha Azza , Sridhar Samanvitha , Frick Jordan R. , Yin Shichen , He Qingquan , Robb Alex J. , Chaaban Maya , Liu He , Winfred J. S. Raaj Vellore , Hanson Kenneth , So Franky , Dougherty Daniel , Ma Biwu
Published: August 2021

Perovskite light‐emitting diodes (PeLEDs) have received great attention for their potential as next‐generation display technology. While remarkable progress has been achieved in green, red, and near‐infrared PeLEDs with external quantum efficiencies (EQEs) exceeding 20%, obtaining high performance blue PeLEDs remains a challenge. Poor charge balance due to large charge injection barriers in blue PeLEDs has been identified as one of the major roadblocks to achieve high efficiency. Here band edge control of perovskite emitting layers for blue PeLEDs with enhanced charge balance and device performance is reported. By using organic spacer cations with different dipole moments, that is, phenethyl ammonium (PEA), methoxy phenethyl ammonium (MePEA), and 4‐fluoro phenethyl ammonium (4FPEA), the band edges of quasi‐2D perovskites are tuned without affecting their band gaps. Detailed characterization and computational studies have confirmed the effect of dipole moment modification to be mostly electrostatic, resulting in changes in the ionization energies of ≈0.45 eV for MePEA and ≈ −0.65 eV for 4FPEA based thin films relative to PEA‐based thin films. With improved charge balance, blue PeLEDs based on MePEA quasi‐2D perovskites show twofold increase of the EQE as compared to the control PEA based devices.
Function‐Targeted Lanthanide‐Anchored Polyoxometalate–Cyclodextrin Assembly: Discriminative Sensing of Inorganic Phosphate and Organophosphate
Authors: Li Qiuju , Wang Dandan , Fang Xian , Wang Xingyi , Mao Shun , Ostrikov Kostya (Ken)
Published: August 2021

Polyoxometalate (POM) clusters containing lanthanide ion (LnPOM) possess excellent luminescence features, but the envisaged applications are hindered by the challenges in integration into functional architectures. Herein, a novel cross‐linked cyclodextrin (CL‐CD) and LnPOM composite is developed and applied for discriminative detection of inorganic and organic phosphate phases. For inorganic phosphates, a ratiometric fluorescence response is demonstrated with excellent selectivity, and anti‐interference ability in complex analyte mixtures. The outstanding performance is attributed to the high affinity of POM and distinct interactions between La3+ and Eu3+ with the phosphate. For organophosphates, a “signal‐off” fluorescence response for p‐nitrophenyl‐substituted organophosphates is discovered due to the encapsulation of nitrophenyl group into the hydrophobic cavity of CD that enhances the interactions between POM and p‐nitrophenyl phosphate. The discriminative responses of CL‐CD–LnPOM to inorganic phosphates and organophosphates bring new insights into POM‐based fluorescence probes for the detection of inorganic and organic phases based on the intrinsic structural difference between the phosphate analogs.
Low‐Molecular‐Weight Supramolecular‐Polymer Double‐Network Eutectogels for Self‐Adhesive and Bidirectional Sensors
Authors: Liang Yujia , Wang Kaifang , Li Jingjing , Wang Hai , Xie Xiao‐Qiao , Cui Yihan , Zhang Yunfei , Wang Mengke , Liu Chun‐Sen
Published: August 2021

Ionic conducting eutectogels have attracted enormous attention as an alternative to the conventional temperature‐intolerant hydrogels and costly ionic liquid gels in constructing flexible electronic devices. However, current eutectogels prepared via cross‐linked polymer or low‐molecular‐weight gelators suffer from limited stretchability and insufficient surface‐adaptive adhesion. Herein, a low‐molecular‐weight supramolecular network is introduced into a covalent polymer network in a eutectogel architecture, and a novel supramolecular‐polymer double‐network (SP‐DN) strategy is demonstrated to fabricate conductive SP‐DN eutectogels with high stretchability (>4000% elongation) and toughness (≈800 J m−2), as well as self‐healing, self‐adhesive and anti‐freezing/anti‐drying characteristics. These unique features lead to the successful realization of SP‐DN eutectogels in wearable self‐adhesive strain sensors, which can conformally deform with the skin and dynamically monitor body movements with high sensitivity and long‐term stability over a wide temperature range (−40 to 60 °C). Furthermore, the strain sensors can accurately detect body movements along two opposite directions (bend up or bend down), which are rarely reported in the literature. Distinct from the widely explored polymer double‐network (P‐DN) hydrogels, the developed SP‐DN eutectogel platform is capable of well‐regulating molecular‐scale noncovalent and covalent interactions, providing a paradigm for the creation of smart soft materials with versatile performance and high environmental adaptability.
Advanced Electrolytes Enabling Safe and Stable Rechargeable Li‐Metal Batteries: Progress and Prospects
Authors: Tan Shuang‐Jie , Wang Wen‐Peng , Tian Yi‐Fan , Xin Sen , Guo Yu‐Guo
Published: August 2021

Rechargeable Li‐metal batteries (RLBs) can boost energy yet possess poor cycle stability and safety concerns when utilizing carbonate electrolytes. Countless effort has been invested in researching and developing electrolytes for RLBs to obtain stable and safe batteries. However, only few existing electrolytes meet the requirements for practical RLBs. In this perspective, the challenges of organic liquid electrolytes in the application in RLBs are summarized, and requirements for electrolytes for practical RLBs are proposed. This perspective briefly reviews the recent achievements of electrolytes (liquid‐ and solid‐state) for RLBs and analyzes the corresponding drawbacks of each electrolyte. Further, possible solutions to the existing shortcomings of various electrolytes are proposed. In particular, this perspective outlines the development strategy of in situ gelation electrolytes, accompanied by a call for people using pouch cells to evaluate performance and paying more attention to battery safety research. This perspective aims to expound on the challenges and the possible research directions of RLBs electrolytes to promote practical RLBs better.
Gold‐Doped Covalent Organic Framework Reveals Specific Serum Metabolic Fingerprints as Point of Crohn's Disease Diagnosis
Authors: Yang Chenjie , Yu Hailong , Hu Xufang , Chen Haolin , Wu Hao , Deng Chunhui , Sun Nianrong
Published: August 2021

Currently, most Crohn's disease (CD) patients suffer from serious complications and even surgery due to delayed diagnosis; therefore, point‐of‐care diagnosis of CD is urgently required. In this work, a covalent organic framework@Au (COF‐V@Au) matrix material with excellent laser absorption is prepared, endowing metabolites with great ionization efficiency in laser desorption/ionization mass spectrometry (LDI‐MS) analysis. In addition, the COF‐V@Au matrix possesses 1093 m2 g−1 of large specific surface area and around 2 nm of average pore size, providing abundant sites and efficient structure for metabolite adsorption. Benefiting from high throughput, high sensitivity, and high ionization efficiency of COF‐V@Au assisted LDI‐MS, the extraction of serum metabolic fingerprints of CD group and healthy group is implemented. Moreover, the two groups are successfully distinguished with an area under the curve (AUC) value of 0.984 by establishing an orthogonal partial least squares discriminant analysis (OPLS‐DA) model of Crohn's patients versus healthy controls. Moreover, the expression of 25 features is determined as the prominent metabolic differences between CD patients and the controls. Furthermore, the terminal ileum and ileocolon subtypes of CD are also distinguished from healthy controls with AUC value of 0.989 and 0.991, respectively. Thus, this COF‐V@Au‐assisted LDI‐MS method is expected to be a clinical diagnostic technology in the future.
A Nanotheranostic System Combining Lysosomal Cell Death and Nuclear Apoptosis Functions for Synergistic Cancer Therapy and Addressing Drug Resistance
Authors: Li Youmei , Wu Qian , Li Dan , Huang Jiachang , Wen Haifei , Wu Yi , Wang Dong , Tang Ben Zhong
Published: August 2021

The lysosome is a prominent and crucial target for actualizing anticancer therapy due to the outstanding therapeutic effect of lysosomal cell death on apoptosis‐ and drug‐resistance cancer. Exploration of multifunctional materials involving lysosome‐targeting drugs for achieving efficient cancer treatment is definitely appealing, yet a significantly challenging task. Herein, a versatile nanotheranostic system allowing all cancer cell‐targeting, tumor microenvironment stimuli‐responsive, fluorescence imaging, lysosome‐targeting chemotherapy and nucleus‐targeting chemotherapy functions was tactfully designed and constructed, by encapsulating both doxorubicin and a lysosome‐specific targeting drug with aggregation‐induced emission features in functional amphiphilic polymers. Both in vitro and in vivo studies revealed that the presented nanotheranostic system exhibited synergistic anticancer therapy effects, negligible systemic toxicity, and remarkable inhibition of drug‐resistant cancer cells. This study thus brings a new insight into the development of a superior effective protocol for practical cancer treatment.
Addressing Particle Compositional Heterogeneities in Super‐Resolution‐Enhanced Live‐Cell Ratiometric pH Sensing with Ultrasmall Fluorescent Core–Shell Aluminosilicate Nanoparticles
Authors: Lee Rachel , Erstling Jacob A. , Hinckley Joshua A. , Chapman Dana V. , Wiesner Ulrich B.
Published: August 2021

The interrogation of metabolic parameters like pH in live‐cell experiments using optical super‐resolution microscopy (SRM) remains challenging. This is due to a paucity of appropriate metabolic probes enabling live‐cell SRM‐based sensing. Here, ultrasmall fluorescent core–shell aluminosilicate nanoparticle sensors (FAM–ATTO647N aC′ dots) that covalently encapsulate a reference dye (ATTO647N) in the core and a pH‐sensing moiety (FAM) in the shell are introduced. Only the reference dye exhibits optical blinking enabling live‐cell stochastic optical reconstruction microscopy (STORM). Using data from cells incubated for 60 min with FAM–ATTO647N aC′ dots, pixelated information from total internal reflection fluorescence (TIRF) microscopy‐based ratiometric sensing can be combined with that from STORM‐based localizations via the blinking reference dye in order to enhance the resolution of ratiometric pH sensor maps beyond the optical diffraction limit. A nearest‐neighbor interpolation methodology is developed to quantitatively address particle compositional heterogeneity as determined by separate single‐particle fluorescence imaging methods. When combined with STORM‐based estimates of the number of particles per vesicle, vesicle size, and vesicular motion as a whole, this analysis provides detailed live‐cell spatial and functional information, paving the way to a comprehensive mapping and understanding of the spatiotemporal evolution of nanoparticle processing by cells important, e.g., for applications in nanomedicine.
Organic Semiconducting Luminophores for Near‐Infrared Afterglow, Chemiluminescence, and Bioluminescence Imaging
Authors: Li Xiaozhen , Yin Chao , Liew Si Si , Lee Chun‐Sing , Pu Kanyi
Published: August 2021

Optical imaging has played a pivotal role in deciphering in vivo bioinformatics but is limited by shallow penetration depth and poor imaging performance owing to interfering tissue autofluorescence induced by concurrent photoexcitation. The emergence of near‐infrared (NIR) self‐luminescence imaging independent of real‐time irradiation has timely addressed these problems. There are two main kinds of self‐luminescent agents, namely inorganic and organic luminophores. Inorganic luminophores usually suffer from long‐term biotoxicity concerns resulting from potential heavy‐metal ions leakage and nonbiodegradability, which hinders their further translational application. In contrast, organic luminophores, especially organic semiconducting luminophores (OSLs) with good biodegradable potential, tunable design, and outstanding optical properties, are preferred in biological applications. This review summarizes the recent progress of OSLs used in NIR afterglow, chemiluminescence, and bioluminescence imaging. Molecular manipulation and nanoengineering approaches of OSLs are discussed, with emphasis on strategies that can extend the emission wavelength from visible to NIR range and amplify luminescence signals. This review concludes with a discussion of current challenges and possible solutions of OSLs in the self‐luminescence field.
Micropatterns Fabricated by Photodimerization‐Induced Diffusion
Authors: Li Tiantian , Ma Tianjiao , Li Jin , Chen Shuai , Ma Xiaodong , Yin Jie , Jiang Xuesong
Published: August 2021

Pattern technology plays an important role in the generation of microstructures with different functionalities and morphologies. In this report, a straightforward and versatile strategy is presented for spatially regulating the growth of a microstructure on a surface by the photodimerization of maleimide (MI). Upon exposure of ultraviolet (UV) light, photodimerization of MI in a film comprising furan‐grafted polymer and bismaleimide (BMI) produces a chemical gradient, which can drive the diffusion of BMI from the unexposed to the exposed region and from the bottom to the surface, resulting in the growth of micropatterns. Sequential crosslinking induced by the Diels–Alder reaction between MI and furan maintains the stability of pattern shape. Theoretical modeling with reaction‐diffusion equations reveal that as photodimerization moves the system far from thermodynamic equilibrium, the formation of a chemical potential gradient requires the redistribution of matter, resulting in the formation of topographies. Directional molecular motion induced by UV light can generate complex morphology, and produce materials with unique optical functions, such as charming‐ordered gratings. This straightforward method of fabricating micropatterns by photodimerization‐induced diffusion is successfully applied to patterned curved surfaces, microfluidic channels and encapsulation of integrated light emitting diode chips.
Dynamic Symmetry Breaking in Chiral Magnetic Systems
Authors: Brock Jeffrey A. , Kitcher Michael D. , Vallobra Pierre , Medapalli Rajasekhar , Li Maxwell P. , De Graef Marc , Riley Grant A. , Nembach Hans T. , Mangin Stéphane , Sokalski Vincent , Fullerton Eric E.
Published: August 2021

The Dzyaloshinskii–Moriya interaction (DMI) in magnetic systems stabilizes spin textures with preferred chirality, applicable to next‐generation memory and computing architectures. In perpendicularly magnetized heavy‐metal/ferromagnet films, the interfacial DMI originating from structural inversion asymmetry and strong spin‐orbit coupling favors chiral Néel‐type domain walls (DWs) whose energetics and mobility remain at issue. Here, a new effect is characterized in which domains expand unidirectionally in response to a combination of out‐of‐plane and in‐plane magnetic fields, with the growth direction controlled by the in‐plane field strength. These growth directionalities and symmetries with applied fields cannot be understood from static treatments alone. The authors theoretically demonstrate that perpendicular field torques stabilize steady‐state magnetization profiles highly asymmetric in elastic energy, resulting in a dynamic symmetry breaking consistent with the experimental findings. This phenomenon sheds light on the mechanisms governing the dynamics of Néel‐type DWs and expands the utility of field‐driven DW motion to probe and control chiral DWs.
Reduced Intrinsic Non‐Radiative Losses Allow Room‐Temperature Triplet Emission from Purely Organic Emitters
Authors: Li Yungui , Jiang Lihui , Liu Wenlan , Xu Shunqi , Li Tian‐Yi , Fries Felix , Zeika Olaf , Zou Yingping , Ramanan Charusheela , Lenk Simone , Scholz Reinhard , Andrienko Denis , Feng Xinliang , Leo Karl , Reineke Sebastian
Published: August 2021

Persistent luminescence from triplet excitons in organic molecules is rare, as fast non‐radiative deactivation typically dominates over radiative transitions. This work demonstrates that the substitution of a hydrogen atom in a derivative of phenanthroimidazole with an N‐phenyl ring can substantially stabilize the excited state. This stabilization converts an organic material without phosphorescence emission into a molecular system exhibiting efficient and ultralong afterglow phosphorescence at room temperature. Results from systematic photophysical investigations, kinetic modeling, excited‐state dynamic modeling, and single‐crystal structure analysis identify that the long‐lived triplets originate from a reduction of intrinsic non‐radiative molecular relaxations. Further modification of the N‐phenyl ring with halogen atoms affects the afterglow lifetime and quantum yield. As a proof‐of‐concept, an anticounterfeiting device is demonstrated with a time‐dependent Morse code feature for data encryption based on these emitters. A fundamental design principle is outlined to achieve long‐lived and emissive triplet states by suppressing intrinsic non‐radiative relaxations in the form of molecular vibrations or rotations.
Ultrafast Bubble Bursting by Superamphiphobic Coatings
Authors: Hegner Katharina I. , Wong William S. Y. , Vollmer Doris
Published: August 2021

Controlling bubble motion or passively bursting bubbles using solid interfaces is advantageous in numerous industrial applications including flotation, catalysis, electrochemical processes, and microfluidics. Current research has explored the formation, dissolution, pinning, and rupturing of bubbles on different surfaces. However, the ability to tune and control the rate of bubble bursting is not yet achieved. Scaling down surface‐induced bubble bursting to just a few milliseconds is important for any application. In this work, the hierarchical structure of superamphiphobic surfaces is tuned in order to rapidly rupture contacting bubbles. Surfaces prepared using liquid flame spray show ultrafast bubble bursting (down to 2 ms) and superior durability. The coatings demonstrate excellent mechanical and chemical stability even in the presence of surface‐active species. Air from the ruptured bubble is absorbed into the aerophilic Cassie‐state. Long‐term applicability is demonstrated by preventing the accumulation of air in the plastron via a connection of the plastron to the environment. The times recorded for bubble rupture and complete reorganization of air are reduced by approximately a factor of 3 compared to previously reported values. The concept is utilized to passively control surfactant‐rich foam in froth flotation. Material collection efficiency increased by more than 60 times compared to controls.
Wavelength‐Selective Softening of Hydrogel Networks
Authors: Pelloth Jessica L. , Tran Phong A. , Walther Andreas , Goldmann Anja S. , Frisch Hendrik , Truong Vinh X. , Barner‐Kowollik Christopher
Published: August 2021

Photoresponsive hydrogels hold key potential in advanced biomedical applications including tissue engineering, regenerative medicine, and drug delivery, as well as intricately engineered functions such as biosensing, soft robotics, and bioelectronics. Herein, the wavelength‐dependent degradation of bio‐orthogonal poly(ethylene glycol) hydrogels is reported, using three selective activation levels. Specifically, three chromophores are exploited, that is,ortho‐nitrobenzene, dimethyl aminobenzene, and bimane, each absorbing light at different wavelengths. By examining their photochemical action plots, the wavelength‐dependent reactivity of the photocleavable moieties is determined. The wavelength‐selective addressability of individual photoreactive units is subsequently translated into hydrogel design, enabling wavelength‐dependent cleavage of the hydrogel networks on‐demand. Critically, this platform technology allows for the fabrication of various hydrogels, whose mechanical properties can be fine‐tuned using different colors of light to reach a predefined value, according to the chromophore ratios used. The softening is shown to influence the spreading of pre‐osteoblastic cells adhering to the gels as a demonstration of their potential utility. Furthermore, the materials and photodegradation processes are non‐toxic to cells, making this platform attractive for biomaterials engineering.
Full‐Color Holographic Display and Encryption with Full‐Polarization Degree of Freedom
Authors: Guo Xuyue , Zhong Jinzhan , Li Bingjie , Qi Shuxia , Li Yu , Li Peng , Wen Dandan , Liu Sheng , Wei Bingyan , Zhao Jianlin
Published: August 2021

Metasurfaces provide a compact and powerful platform for manipulating the fundamental properties of light, and have shown unprecedented capabilities in both optical holographic display and information encryption. For increasing information display/storage capacity, metasurfaces with more polarization manipulation channel and full‐color holographic functionality are now an urgent requirement. Here, a minimalist dielectric metasurface with the capability of full‐color holography encoded with arbitrary polarization is proposed and experimentally demonstrated. Without the daunting exploratory and computational problem in nanostructure searching, full‐color holographic images can be multiplexed into arbitrary polarization channels through vectorial ptychography and k‐space ptychography based on tetratomic macropixel geometric phase metasurfaces. Thanks to the full degree of freedom tuning in polarization and color spaces, the application scenarios such as holographic 3D imaging and information encryption are realized. The strategy exhibits promising potential in applications of 3Dl display, augmented/virtual reality, high‐density data storage, and encryption.
Biologically Enhanced Starch Bio‐Ink for Promoting 3D Cell Growth
Authors: Zhuang Pei , Greenberg Zachary , He Mei
Published: August 2021

The excellent rheological property has legitimated the suitability of starch hydrogel for extrusion‐based 3D printing. However, the inability to promote cell attachment and migration has precluded the non‐modified starch hydrogel from direct applications in the biomedical field. Herein, a novel 3D printable nanocomposite starch hydrogel is developed with highly enhanced biocompatibility for promoting 3D cell growth, by formulating with gelatin nanoparticles and collagen. The rheological evaluation reveals the shear‐thinning and thixotropic properties of the starch‐based hydrogel, as well as the combinatorial effect of collagen and gelatin nanoparticles on maintaining printability and 3D shape fidelity. The homogeneous microporous structure with abundant collagen fibers and gelatin nanoparticles interlace and supplies rich attachment sites for cell growth. Corroborated by the cell metabolic activity study, the multiplied proliferation rate of cells on the 3D printed nanocomposite starch hydrogel scaffold confirms the remarkable enhancement of biological function of the developed starch hydrogel. Hence, the developed nanocomposite starch hydrogel serves as a highly desirable bio‐ink for advancing 3D tissue engineering.
Quadrupole Last‐Passage Algorithm for Charge Density on an L‐Shaped Conducting Surface
Authors: Jang Hoseung , Park Jongmin , Yu Unjong , Hwang Chi‐Ok
Published: August 2021

The last‐passage (LP) Monte Carlo algorithms for the charge density on an L‐shaped conducting surface are further developed by deriving a quadrupole LP Green's function on the L‐shaped flat surface. To demonstrate the algorithm, charge densities on an L‐shaped conductor are computed in 3D space and it is found that these results agree very well with the ones from the Given‐Hwang's original last‐passage algorithm on a flat surface. Compared with the Given‐Hwang's LP algorithm, the quadrupole LP one is very suitable for charge density near the L‐shaped edge boundary.
Synergistic SERS Enhancement in GaN‐Ag Hybrid System toward Label‐Free and Multiplexed Detection of Antibiotics in Aqueous Solutions
Authors: Lee Kang Hyun , Jang Hanhwi , Kim Yoon Seok , Lee Chul‐Ho , Cho Seunghee H. , Kim Minjoon , Son Hoki , Bae Kang Bin , Dao Dung Van , Jung Yeon Sik , Lee In‐Hwan
Published: August 2021

Noble metal‐based surface‐enhanced Raman spectroscopy (SERS) has enabled the simple and efficient detection of trace‐amount molecules via significant electromagnetic enhancements at hot spots. However, the small Raman cross‐section of various analytes forces the use of a Raman reporter for specific surface functionalization, which is time‐consuming and limited to low‐molecular‐weight analytes. To tackle these issues, a hybrid SERS substrate utilizing Ag as plasmonic structures and GaN as charge transfer enhancement centers is presented. By the conformal printing of Ag nanowires onto GaN nanopillars, a highly sensitive SERS substrate with excellent uniformity can be fabricated. As a result, remarkable SERS performance with a substrate enhancement factor of 1.4 × 1011 at 10 fM for rhodamine 6G molecules with minimal spot variations can be realized. Furthermore, quantification and multiplexing capabilities without surface treatments are demonstrated by detecting harmful antibiotics in aqueous solutions. This work paves the way for the development of a highly sensitive SERS substrate by constructing complex metal‐semiconductor architectures.
Single‐Cell RNA‐Seq of T Cells in B‐ALL Patients Reveals an Exhausted Subset with Remarkable Heterogeneity
Authors: Wang Xiaofang , Chen Yanjuan , Li Zongcheng , Huang Bingyan , Xu Ling , Lai Jing , Lu Yuhong , Zha Xianfeng , Liu Bing , Lan Yu , Li Yangqiu
Published: August 2021

Characterization of functional T cell clusters is key to developing strategies for immunotherapy and predicting clinical responses in leukemia. Here, single‐cell RNA sequencing is performed with T cells sorted from the peripheral blood of healthy individuals and patients with B cell‐acute lymphoblastic leukemia (B‐ALL). Unbiased bioinformatics analysis enabled the authors to identify 13 T cell clusters in the patients based on their molecular properties. All 11 major T cell subsets in healthy individuals are found in the patients with B‐ALL, with the counterparts in the patients universally showing more activated characteristics. Two exhausted T cell populations, characterized by up‐regulation of TIGIT, PDCD1, HLADRA, LAG3, and CTLA4 are specifically discovered in B‐ALL patients. Of note, these exhausted T cells possess remarkable heterogeneity, and ten sub‐clusters are further identified, which are characterized by different cell cycle phases, naïve states, and GNLY (coding granulysin) expression. Coupled with single‐cell T cell receptor repertoire profiling, diverse originations of the exhausted T cells in B‐ALL are suggested, and clonally expanded exhausted T cells are likely to originate from CD8+ effector memory/terminal effector cells. Together, these data provide for the first‐time valuable insights for understanding exhausted T cell populations in leukemia.
Advanced Cancer Starvation Therapy by Simultaneous Deprivation of Lactate and Glucose Using a MOF Nanoplatform
Authors: Yu Jiantao , Wei Zixiang , Li Qing , Wan Feiyan , Chao Zhicong , Zhang Xindan , Lin Li , Meng Hong , Tian Leilei
Published: August 2021

Recent investigations reveal that lactate is not a waste product but a major energy source for cells, especially in the mitochondria, which can support cellular survival under glucose shortage. Accordingly, the new understanding of lactate prompts to target it together with glucose to pursue a more efficient cancer starvation therapy. Herein, zeolitic imidazolate framework‐8 (ZIF‐8) nanoplatforms are used to co‐deliver α‐cyano‐4‐hydroxycinnamate (CHC) and glucose oxidase (GOx) and fulfill the task of simultaneous depriving of lactate and glucose, resulting in a new nanomedicine CHC/GOx@ZIF‐8. The synthesis conditions are carefully optimized in order to yield monodisperse and uniform nanomedicines, which will ensure reliable and steady therapeutic properties. Compared with the strategies aiming at a single carbon source, improved starvation therapy efficacy is observed. Besides, more than boosting the energy shortage, CHC/GOx@ZIF‐8 can block the lactate‐fueled respiration and relieve solid tumor hypoxia, which will enhance GOx catalysis activity, depleting extra glucose, and producing more cytotoxic H2O2. By the synergistically enhanced anti‐tumor effect, both in vitro and in vivo cancer‐killing efficacies of CHC/GOx@ZIF‐8 show twice enhancements than the GOx mediated therapy. The results demonstrate that the dual‐depriving of lactate and glucose is a more advanced strategy for strengthening cancer starvation therapy.
Novel Stacking Design of a Flexible Thin‐Film Thermoelectric Generator with a Metal–Insulator–Semiconductor Architecture
Authors: Tao Xudong , Hao Botao , Assender Hazel E.
Published: August 2021

A stacked thermoelectric generator on a flexible polymer sheet is investigated that can utilize a low‐cost high throughput roll‐to‐roll process, employing a metal–insulator–semiconductor structure of <100 nm thick Cu and bismuth telluride films with a ≈1 µm thick acrylate insulating coating. Thermoelectric strips can be stacked and connected in the out‐of‐plane direction, which significantly decreases the size required in the substrate plane and also gives rise to the opportunity for greatly extending power output by stacking thousands of layers. A smooth surface of stacked layers is confirmed due to the nature of the acrylate layer. Room‐temperature sputtering can produce good quality/crystalline films, indicated by X‐ray diffraction and transmission electron microscope. Both experimental and simulation results observe a small temperature gradient across the stack from the bottom heat source to the top free surface. A stacked thermoelectric generator shows comparable performance to an in‐plane device, and most notably, the stacked architecture allows a higher power output without increasing the dimension of the device in the substrate plane, while the thickness is increased within only a µm range. Cyclic buckling fatigue tests suggest that the performance of stacked functional strips can be protected under deformation within the acrylate matrix.
Enhanced N‐Type Doping of a Naphthalene Diimide Based Copolymer by Modification of the Donor Unit
Authors: Cassinelli Marco , Cimò Simone , Biskup Till , Jiao Xuechen , Luzio Alessandro , McNeill Christopher R. , Noh Yong‐Young , Kim Yun‐Hi , Bertarelli Chiara , Caironi Mario
Published: August 2021

Doped conjugated organic semiconductors are suitable materials to be used as building blocks of flexible and cost‐effective thermoelectric generators. While several efficient solution‐processable p‐type organic thermoelectric materials are reported, n‐doped materials are fewer because of lack of good electron‐transporting materials and stable n‐dopants. Here, n‐doping process is investigated on a relevant n‐type class, namely naphthalene‐diimide‐based copolymers. Among these, copolymer incorporating bithiophene (T2) donor units, largely studied poly{N,N″‐bis(2‐octyl‐dodecyl)‐1,4,5,8‐naphthalenedicarboximide‐2,6‐diyl]‐alt‐5,5′‐(2,2′‐bithiophene)} (PNDI‐T2), is one of first polymers reported to achieve good solution‐based n‐doping. By substituting T2 with thienylenevinylene‐thienylene (TVT), resulting PNDI‐TVT copolymer exhibits improvements on both structural and transport properties, offering a suitable basis to improve thermoelectric properties upon doping. When doped with 1H‐benzimidazoles, PNDI‐TVT achieves maximum in‐plane electrical conductivity at room temperature of 2.4 × 10−2 S cm−1, being the highest value for PNDI‐T2 solution‐doped derivatives excluding those with oligoethylene‐glycol chains. Electron paramagnetic resonance and variable temperature electrical conductivity measurements relate this enhancement to more efficient charge‐transfer between n‐dopant molecules and host polymeric matrix, and easier charge carrier transport within the system. This electrical conductivity large enhancement also improves in‐plane power factor of almost three times with respect to similar doped PNDI‐T2 films.
Single‐Ion Conducting Soft Electrolytes for Semi‐Solid Lithium Metal Batteries Enabling Cell Fabrication and Operation under Ambient Conditions
Authors: Oh Kyeong‐Seok , Kim Jung‐Hui , Kim Se‐Hee , Oh Dongrak , Han Sun‐Phil , Jung Kwangeun , Wang Zhuyi , Shi Liyi , Su Yongxiang , Yim Taeeun , Yuan Shuai , Lee Sang‐Young
Published: August 2021

Despite their potential as post lithium‐ion batteries, solid‐state Li‐metal batteries are struggling with insufficient electrochemical sustainability and ambient operation limitations. These challenges mainly stem from lack of reliable solid‐state electrolytes. Here, a new class of single‐ion conducting quasi‐solid‐state soft electrolyte (SICSE) for practical semi‐solid Li‐metal batteries (SSLMBs) is demonstrated. The SICSE consists of an ion‐rectifying compliant skeleton and a nonflammable coordinated electrolyte. Rheology‐tuned SICSE pastes, in combination with UV curing‐assisted multistage printing, allow fabrication of seamlessly integrated SSLMBs (composed of a Li metal anode and LiNi0.8Co0.1Mn0.1 cathode) without undergoing high‐pressure/high‐temperature manufacturing steps. The single‐ion conducting capability of the SICSE plays a viable role in stabilizing the interfaces with the electrodes. The resulting SSLMB full cell exhibits stable cycling performance and bipolar configurations with tunable voltages and high gravimetric/volumetric energy densities (476 Wh kgcell−1/1102 Wh Lcell−1 at four‐stacked cells with 16.656 V) under ambient operating conditions, along with low‐temperature performance, mechanical foldability, and nonflammability.
Boron Strengthened GeTe‐Based Alloys for Robust Thermoelectric Devices with High Output Power Density
Authors: Bai Guangyuan , Yu Yuan , Wu Xuelian , Li Junqin , Xie Yucheng , Hu Lipeng , Liu Fusheng , Wuttig Matthias , Cojocaru‐Mirédin Oana , Zhang Chaohua
Published: August 2021

High‐performance thermoelectric (TE) devices require not only a high figure of merit (ZT) but also mechanical strength and thermal stability. Here, a simultaneous enhancement of ZT as well as mechanical properties is obtained in GeTe‐based alloys by adding boron. This material is then assembled with n‐type CoSb3 skutterudite into TE modules. The improved ZT values result from the increase in charge carrier mobility due to the reduced interfacial barrier height. A peak ZT of 2.2 at 773 K can be achieved in Ge0.84Pb0.1Sb0.06TeB0.07, which shows a negligible change in the coefficient of thermal expansion upon the phase transition from the rhombohedral to the cubic phase, ensuring good thermal stability of the device. Resulting from the boron‐induced grain refinement and dispersion strengthening, the average compressive strength and Vickers hardness of Ge0.9Sb0.1TeB0.07 can be enhanced to ≈227 MPa and ≈202 Hv, respectively. The improved mechanical properties facilitate the assembly of devices and lower the interfacial contact resistance. As a synergy of increased ZT and mechanical strength, a high output power density of ≈1.76 W cm−2 at ΔT = 425 K and an energy conversion efficiency of 7.4% at ΔT = 477 K can be achieved in the TE modules.
The medium‐term impacts of integrated crop–livestock systems on crop yield and economic performance
Authors: Rai Teerath Singh , Nleya Thandiwe , Kumar Sandeep , Sexton Peter , Wang Tong , Fan Yubing
Published: August 2021

Integrated crop–livestock (ICL) systems are diverse production systems that can improve resource utilization through spatially or temporally rotating land among crop, livestock, and pasture uses. However, research on whether the enhanced resource utilization translates to greater crop productivity is still warranted. A field experiment was initiated at South Dakota State University in 2016 to determine the impacts of integrating cover crops and livestock grazing into a crop rotation of oat (Avena sativa L.)–maize (Zea mays L.)–soybean [Glycine max (L.) Merr.]. The objectives were to (a) determine the medium‐term (4–6 yr) impacts of cover crops and livestock grazing on crop performance, and (b) determine the economic impacts of integrating cover crops and livestock grazing. Treatments included (a) a cover crop blend planted after oat harvesting (CC), (b) a CC blend that was the same as in (a) but with grazing of the CC and crop residue in late fall (ICL), and (c) a control treatment without any CC or livestock grazing. The results showed that planting cover crops, with or without grazing, did not impact the subsequent crop yield. Maize yield decreased by 17.7% in a dry year in 2017 in the CC treatment compared with the control; however, the difference was nonsignificant (P = .06). Economic analysis showed that the net revenue generated by the ICL system could compensate for the additional costs incurred by integrating cover crops into the crop production system.
Liming and phosphorus fertilization increase cassava root yield without affecting its cooking time
Authors: Rosa Ben‐Hur S. , Fernandes Adalton M. , Gazola Bruno , Nunes Jesion G. S. , Soratto Rogério P.
Published: August 2021

Acidity and low P availability in tropical soils constrain cassava (Manihot esculenta Crantz) yield. Liming increases soil Ca and P availability, but Ca can increase the storage root cooking time, and its effects vary with soil P availability. The effects of liming and P fertilization on cassava yield and their relationship with storage root cooking need to be better understood. A 2‐yr field experiment was conducted to evaluate the effect of liming at 0, 1.5, 3.1, and 4.8 Mg ha−1 with 0 or 70 kg P ha−1 on plant nutritional status and growth, yield, and cooking of fresh storage roots of the cassava cultivar IAC 576‐70. Foliar concentrations were increased for N, P, and Mg and reduced for Mn and Zn with lime application. Maximum cassava fresh storage root yield (26.4 Mg ha−1) was obtained with an optimal lime rate of 3.0 Mg ha−1 and a base saturation of 50%. Liming promoted a 6.5% increase (1.7 min) in the cooking time of storage roots. Application of P fertilizer increased shoot biomass in acidic soil and the diameter and mean weight of the storage roots in the amended soil. Phosphorus fertilization increased the yield (22% or 4.7 Mg ha−1) and P concentration of the storage roots without changing their P/Ca ratio or cooking time. Liming and P fertilization can be managed to improve cassava storage root yield without affecting storage root cooking.
System‐Engineered Miniaturized Robots: From Structure to Intelligence
Authors: Bandari Vineeth Kumar , Schmidt Oliver G.
Published: August 2021

The development of small machines, once envisioned by Feynman decades ago, has stimulated significant research in materials science, robotics, and computer science. Over the past years, the field of miniaturized robotics has rapidly expanded with many research groups contributing to the numerous challenges inherent to this field. Smart materials have played a particularly important role as they have imparted miniaturized robots with new functionalities and distinct capabilities. However, despite all efforts and many available soft materials and innovative technologies, a fully autonomous system‐engineered miniaturized robot (SEMR) of any practical relevance has not been developed yet. In this review, the foundation of SEMRs is discussed and six main areas (structure, motion, sensing, actuation, energy, and intelligence) which require particular efforts to push the frontiers of SEMRs further are identified. During the past decade, miniaturized robotic research has mainly relied on simplicity in design, and fabrication. A careful examination of current SEMRs that are physically, mechanically, and electrically engineered shows that they fall short in many ways concerning miniaturization, full‐scale integration, and self‐sufficiency. Some of these issues have been identified in this review. Some are inevitably yet to be explored, thus, allowing to set the stage for the next generation of intelligent, and autonomously operating SEMRs.
Development of a green integrated process for biodiesel esters production: Use of fermented macaúba cake as biocatalyst for macaúba acid oil transesterification
Authors: Ávila Sabrini N. S. , Collaço Ana Cristina A. , Greco‐Duarte Jaqueline , Aguieiras Erika C. G. , Ambrósio Priscila R. S. , de Castro Aline M. , Gutarra Melissa L. E. , Cavalcanti Elisa D. C. , Freire Denise M. G.
Published: August 2021

In this study, a new green integrated process for biodiesel ester production was developed, consisting of the enzymatic transesterification of acid oil from macaúba palm tree (Acrocomia aculeata) catalyzed by dry fermented solid (DFS) with lipase activity, which was obtained from solid‐state fermentation (SSF) of macaúba cake. Analysis of statistical experimental designs showed that nitrogen supplementation of macaúba cake improved production of lipases displaying esterification capacity by Rhizomucor miehei. The conditions chosen to produce R. miehei DFS were cake supplementation with 2 wt% urea, 60 wt% of initial moisture during 48 h of fermentation at 40°C. DFS showed, by zymography assays, at least one enzyme that was different from those that are present in the commercial lipase of R. miehei. Furthermore, DFS was used in transesterification reactions between macaúba acid oil and alcohol (methanol or ethanol), and the ester content obtained was 92%. This is the first time that this integrated process using low‐cost biocatalysts and a low‐value oil derived from the processing of the same fruit was used for biodiesel ester production, reducing costs and logistic constraints, and optimizing the raw material utilization.