bluuebunny/crossref_metadata_2025 huggingface dataset:
Evaluation of dosimetric functions for a new 169Yb HDR Brachytherapy Source
Authors: Safaeipour Elham , Poorbaygi Hosein , Jabbari Iraj , Sheibani Shahab
Published: July 2021

169Yb has been recently used as an HDR brachytherapy source for cancer treatment. In this paper, dosimetric parameters of a new design of 169Yb HDR brachytherapy source were determined by Monte Carlo (MC) method and film dosimetry. In this new source, the radioactive core has been encapsulated twice for safety purposes. The calculations of dosimetric parameters carried out using MC simulation in water and air phantom. In order to exclude photon contamination's cutoff energy, δ was set at 10 keV. TG‐43U1 data dosimetric, including Sk, Λ, g(r), F(r, θ) was computed using outputs from the simulation and their statistical uncertainties were calculated. Dose distribution around the new prototype source in PMMA phantom in the framework of AAPM TG‐43 and TG‐55 recommendations was measured by Radiochromic film (RCF) Gafchromic EBT3. Obtained air kerma strength, Sk, and the dose rate constant, Λ, from simulation has a value of 1.03U ± 0.03 and 1.21 cGyh−1U−1 ± 0.03, respectively. The radial dose function was calculated at radial distances between 0.5 and 10 cm with a maximum value of 1.15 ± 0.03 at 5–6 cm distances. The anisotropy functions for radial distances of 0.5–7 cm and angle distances 0° to180° were calculated. The dosimetric data of the new HDR 169Yb source were compared with another reference source of 169Yb‐HDR and were found that has acceptable compatibility. In addition, the anisotropy function of the MC simulation and film dosimetry method at a distance of 1 cm from this source was obtained and a good agreement was found between the anisotropy results.
Characterization of LiBH4–MgH2 Reactive Hydride Composite System with Scattering and Imaging Methods Using Neutron and Synchrotron Radiation
Authors: Karimi Fahim , Börries Stefan , Pranzas P. Klaus , Metz Oliver , Hoell Armin , Gizer Gökhan , Puszkiel Julián A. , Riglos Maria V. C. , Pistidda Claudio , Dornheim Martin , Klassen Thomas , Schreyer Andreas
Published: July 2021

Reversible solid‐state hydrogen storage in metal hydrides is a key technology for pollution‐free energy conversion systems. Herein, the LiBH2–MgH2 composite system with and without ScCl3 additive is investigated using synchrotron‐ and neutron‐radiation‐based probing methods that can be applied to characterize such lightweight metal–hydrogen systems from nanoscopic levels up to macroscopic scale. Combining the results of neutron‐ and photon‐based methods allows a complementary insight into reaction paths and mechanisms, complex interactions between the hydride matrix and additive, hydrogen distribution, material transport, structural changes, and phase separation in the hydride matrix. The gained knowledge is of great importance for development and optimization of such novel metal‐hydride‐based hydrogen storage systems with respect to future applications.
2D Fillers Highly Boost the Discharge Energy Density of Polymer‐Based Nanocomposites with Trilayered Architecture
Authors: Bai Hairui , Zhu Kun , Wang Zhe , Shen Bo , Zhai Jiwei
Published: July 2021

A new class of trilayered architecture blends polymer‐based nanocomposites with excellent discharge energy densities (Udis) is presented. The preferable energy storage performance is achieved in sandwich structured nanocomposite (PIP) films. The outer polarization‐layers (P‐layer) of the PIP film are composed of Sr2Nb2O7 nanosheets (SNONSs) as well as boron nitride nanosheets (BNNSs) dispersed in poly(vinylidene fluoride) (PVDF)/ polymethyl methacrylate (PMMA) blend polymer matrix (BPM) to provide high dielectric constant, while PVDF/PMMA with BNNSs forms the central insulation‐layer (I‐layer) to offer high dielectric breakdown strength (Eb) of the resulting nanocomposite films. The dielectric performance, Weibull breakdown strength, and energy storage capacity of single and multi‐layer nanocomposites as a function of filler content are systematically examined. The evolution of electric trees is simulated via finite element methods to verify the experimental dielectric breakdown results in single layer nanocomposite films. The PIP film with optimized filler content displays a discharge energy density of 31.42 J cm−3 with a significantly improved charge–discharge efficiency of ≈71% near the Weibull breakdown strength of 655.16 MV m−1, which is the highest among the polymer‐based nanocomposites under the equivalent dielectric breakdown strength at present.
Single‐Component CMOS‐Like Logic using Diketopyrrolopyrrole‐Based Ambipolar Organic Electrochemical Transistors
Authors: Samuel Jibin J. , Garudapalli Ashutosh , Mohapatra Aiswarya Abhisek , Gangadharappa Chandrasekhar , Patil Satish , Aetukuri Naga Phani B.
Published: July 2021

Complementary circuits based on organic electrochemical transistors (OECTs) are attractive for the development of inexpensive and disposable point‐of‐care bioelectronic devices. Ambipolar OECTs, which employ a single channel material, could decrease the fabrication complexity and manufacturing costs of such circuits. An ideal channel material for ambipolar OECTs should be electrochemically stable in aqueous environments, afford facile ion insertion for both cations and anions, and also facilitate high and balanced electron and hole transport. In this study, triethylene glycol functionalized diketopyrrolopyrrole (DPP)‐based polymer is proposed for the development of ambipolar OECTs. It is shown that DPP‐based OECTs have a high and comparable figure of merit for both n‐ and p‐type operations. Logic NOT, NAND, and NOR operations with corresponding complementary circuits constructed from identical DPP‐based OECT devices are demonstrated. This study is an important step toward the development of sophisticated complementary metal–oxide–semiconductor‐like logic circuits using single‐component OECTs.
Mechanosensation Mediates Long‐Range Spatial Decision‐Making in an Aneural Organism
Authors: Murugan Nirosha J. , Kaltman Daniel H. , Jin Paul H. , Chien Melanie , Martinez Ramses , Nguyen Cuong Q. , Kane Anna , Novak Richard , Ingber Donald E. , Levin Michael
Published: July 2021

The unicellular protist Physarum polycephalum is an important emerging model for understanding how aneural organisms process information toward adaptive behavior. Here, it is revealed that Physarum can use mechanosensation to reliably make decisions about distant objects in its environment, preferentially growing in the direction of heavier, substrate‐deforming, but chemically inert masses. This long‐range sensing is abolished by gentle rhythmic mechanical disruption, changing substrate stiffness, or the addition of an inhibitor of mechanosensitive transient receptor potential channels. Additionally, it is demonstrated that Physarum does not respond to the absolute magnitude of strain. Computational modeling reveales that Physarum may perform this calculation by sensing the fraction of its perimeter that is distorted above a threshold substrate strain—a fundamentally novel method of mechanosensation. Using its body as both a distributed sensor array and computational substrate, this aneural organism leverages its unique morphology to make long‐range decisions. Together, these data identify a surprising behavioral preference relying on biomechanical features and quantitatively characterize how the Physarum exploits physics to adaptively regulate its growth and shape.
A Highly Sensitive Graphene Aerogel Pressure Sensor Inspired by Fluffy Spider Leg
Authors: Tian Ye , Han Jingkai , Yang Jiankui , Wu Huaping , Bai Hao
Published: July 2021

Pressure sensors serve as an important part in electronic skin, flexible and wearable devices, by converting external stimuli into easily identifiable electronic signals, where sensitivity is one of the most critical factors for the performance. Here, a highly sensitive pressure sensor is established based on a graphene aerogel film (GAF) with biomimetic architecture inspired by the fluffy leg of spiders to comprehend the gentle vibration of spider web. The biomimetic GAF with lamellar layers and interlayer dendrites is prepared by bidirectional freezing technique. The special fluff‐like dendritic structure between layers accounts for the GAF sensor with excellent performance under pressure: a high sensitivity of 7.48 kPa–1, a low detection limit of 5 Pa, ultrafast response time as 31 ms, and recovery time of 38 ms with working stability after more than 1000 cycles. This biomimetic GAF pressure sensor paves the path for flexible electronics as demonstrated by monitoring real‐time human pulse and weighing of ultralight objects. Additionally, the approach highlights an efficient route of developing highly sensitive pressure sensors through mimicking various biological architectures.
Conductive Fibrous Metal‐Cyanoquinone Complexes with Excellent Microwave Absorption and Shielding Effectiveness at Ultrathin Thickness
Authors: Wu Lipeng , Xie Aming , Wu Fan , Shi Jiaoyan , Sun Qinya , Dong Wei
Published: July 2021

Metal‐cyanoquinone complex shows great potential in various applications due to its unique molecular structure and physicochemical properties, but has not been reported in electromagnetic protection (absorption and shielding) field. In this work, a series of metal‐cyanoquinone complexes including Cu‐TCNQ, Cu‐DCNQI, and Ag‐DCNQI is first synthesized, and then their electromagnetic protection behaviors are systematically investigated. The results suggest that Cu‐DCNQI shows better electromagnetic wave absorption (EMA) performance compared to Cu‐TCNQ and Ag‐DCNQI, where its maximal absorption reaches −33.2 dB under ultrathin thickness of 0.9 mm with a filler‐loading ratio of 20 wt%. Experimental results and first‐principles calculations indicate that Cu‐DCNQI exhibits good electrical conductivity and narrow bandgap, which are considered to be the main two reasons for its excellent EMA performance. Interestingly, when the filler‐loading ratio of CU‐DCNQI increases to 40 wt%, it shows excellent electromagnetic wave interference (EMI) shielding effectiveness (SE). Under the ultrathin thickness of 0.08 mm, its EMI SE exceeds 10 dB in the X‐band, and the maximum SE reaches 76.8 dB at 8.4 GHz. This research broadens the application scope of metal‐cyanoquinone complexes, and provides a new platform for the design and development of novel ultrathin electromagnetic protection materials.
Perovskite‐Type Oxynitride Nanofibers Performing Photocatalytic Oxygen and Hydrogen Generation
Authors: Hofmann Anja , Weiss Morten , Timm Jana , Marschall Roland
Published: July 2021

Ba5Nb4O15 nanofibers with tailored nanofiber diameters are prepared via electrospinning, and treated in ammonia gas to synthesize niobate oxynitride nanofibers. Most importantly, the nanofibers retain their fiber morphology during ammonolysis, and the nanofiber diameter of the converted fibers can be adjusted. Only a thorough characterization, including detailed Rietveld refinements, can reveal that the ammonolysis of Ba5Nb4O15 results not only in BaNbO2N, but also generates Ba2NbO3N as additional oxynitride phase. Such BaNbO2N–Ba2NbO3N composite nanofibers with adjusted nanofiber diameters are applied in photocatalytic water oxidation and hydrogen generation. After decoration with CoNbO4 or Pt cocatalyst, the materials show a diameter‐dependent photocatalytic activity, respectively, with an optimum nanofiber diameter. The presented synthesis demonstrates a novel sol–gel‐derived possibility for nanostructuring of oxynitrides, which can pave the way for new synthesis strategies of nanostructured complex oxynitrides.
Highly Efficient Photocatalytic Anti‐Bacterial Ag Doped Titanium Dioxide Nanofilms with Combination of Reactive Oxygen Species and Ag Ions Releasing for Application of Vascular Implants
Authors: Yao Hang , Jiang Lang , Luo Xiao , Zou Dan , Liu Luying , Yang Ping , Chen Jiang , Zhao Ansha , Huang Nan
Published: July 2021

Silver ions (Ag) as an effective biocidal metal has commercialized various anti‐bacterial materials. However, the high toxicity of Ag ions always induces undesired tissue injuries, impeding development on biomaterials. Recently, reactive oxygen species (ROS) emerges as the most promising agent for anti‐bacterial materials by modulating cell apoptosis. Herein, highly efficient anti‐bacterial Ag‐doped TiO2 nanofilms (TiO2@Agx, x = 1, 2, 3) are reported wherein Ag ions and ROS are produced by controllable photocatalytic reaction upon UV irradiation, which mutually strengthens the anti‐bacterial efficiency to 99.7% (TiO2@Ag2). Importantly, after doping amount screen of Ag ions, the TiO2@Ag2 (Ag: 4.2%) nanofilm exhibits good hemocompatibility, synergistic suppression of smooth muscle cells proliferation with the combination of Ag ions and ROS, while having slight impacts on endothelial cells growth in vitro. Given these features, this nanofilm is applied on vascular stent which requires neointimal inhibition and re‐endothelialization healing for success of implantation. The 4‐weeks’ implantation results reveal effective neointimal inhibition and rapid re‐endothelialization, indicating excellent biocompatibility as vascular stent.
Ultrathin, Flexible, and Transparent Oxide Thin‐Film Transistors by Delamination and Transfer Methods for Deformable Displays
Authors: Ko Jong Beom , Lee Seung Hee , Lee Tae‐Ik , Lee Sangmin , Kim Jingyu , Kim Hyeok , Kim Taek‐Soo , Park Sang‐Hee Ko
Published: July 2021

The attachment of display devices to various objects has attracted much attention due to their ability to present visual information to people in different environments. Such devices should be ultrathin to ensure complete coverage when attached to various objects, making them a critical technology for the development of rollable and stretchable displays. In this study, the fabrication of high‐performance ultrathin oxide thin‐film transistors (TFTs) on a 5 µm‐thick polyethylene terephthalate substrate is demonstrated by the method of delamination and transfer. Molybdenum oxide functions as an exfoliation layer, and the ultrathin devices exhibit full coverage on various objects with complex surface profiles such as contact lens, fabric, and human skin. It is notable that the TFT device exhibits a high optical transparency of greater than 81% and a reasonable electrical performance with a high mobility of 37 cm2 V−1 s−1. Since the oxide TFTs are fabricated without temperature limitations, the devices show reliable electrical performances under gate and illumination stresses. The flexible devices also exhibit excellent transfer characteristics in the bending state, regardless of the bending radius and direction, as well as a high mechanical durability of over 10 000 bending cycles with the bending radius of 3 mm.
Aggregation‐Induced Emission Nanoprobes Working in the NIR‐II Region: From Material Design to Fluorescence Imaging and Phototherapy
Authors: Xu Zhourui , Jiang Yihang , Fan Miaozhuang , Tang Shuo , Liu Maixian , Law Wing‐Cheung , Yang Chengbin , Ying Ming , Ma Mingze , Dong Biqin , Yong Ken‐Tye , Xu Gaixia
Published: July 2021

In recent years, with increasing demands for in vivo fluorescence imaging and photodynamic therapy, light in the second near‐infrared window (NIR‐II; 1000–1700 nm) has attracted tremendous interest because it offers numerous merits, including deep penetration, minimal phototoxicity, diminished tissue autofluorescence, and reduced tissue absorption and scattering. Among the diverse types of nanoparticles, organic nanoprobes with aggregation‐induced emission (AIE) characteristics have emerged as a better option owing to their ultra‐brightness, excellent photostability, low cytotoxicity, and tailorable optical properties. Recent efforts in the AIE realm have revealed advancements in molecular design for long wavelength absorption and multiphoton excitation, which efficiently modulate the working optical region to the NIR‐II region. In this review, the current status of AIE nanoprobes in the NIR‐II window is summarized. Starting with molecular design strategies, recent efforts in fluorescence imaging and photodynamic therapy are then discussed. Finally, perspectives and challenges in this newly emerging field are given. This review hopes to encourage more innovative ideas in material design and biomedical applications for promoting AIE nanoprobes for future clinical translation.
Responsive Bio‐Composites from Magnesium Carbonate Filled Polycaprolactone and Curcumin‐Functionalized Cellulose Fibers
Authors: Quilez‐Molina Ana Isabel , Pasquale Lea , Debellis Doriana , Tedeschi Giacomo , Athanassiou Athanassia , Bayer Ilker S.
Published: July 2021

Development of responsive bio‐based and biodegradable materials is particularly important in food preservation and monitoring technologies. Although replacing conventional plastic products with sustainable alternatives is still a challenge, promising advances have been reported. In this work, the fabrication of responsive bio‐composite films from polycaprolactone (PCL) and magnesium carbonate (MgCO3), known as food additive E504 with melt impregnation into cellulose, is reported. Cellulose fibers are stained/coated with ethanoic curcumin solutions, primarily to protect them against oxidative degradation. The films demonstrate a strong antioxidant effect against fatty and aqueous food simulants with improved oxygen gas barrier properties. Interestingly, the natural chelation of curcumin with magnesium within the composites improves the bioavailability and antioxidant potency of curcumin. Moreover, the composites show reversible color change response detectable by the naked eye in basic solutions or vapors. This response is tested by placing the composite film inside a sealed plastic container containing shrimp at room temperature, but not in direct contact. Due to spoilage, a noticeable color change in the bio‐composites is recorded. These simple, cost‐effective, non‐toxic, and paper‐like flexible bio‐composites can be fabricated on large scale and be used in diverse applications ranging from sustainable packaging to medical applications and freshness indicators.
High‐Efficiency Spatial‐Wave Frequency Multiplication Using Strongly Nonlinear Metasurface
Authors: Wang Hai Peng , Li Yun Bo , Wang Shi Yu , Shen Jia Lin , Li He , Jin Shi , Cui Tie Jun
Published: July 2021

In the past decades, metasurfaces have opened up a promising venue for manipulating lights and electromagnetic (EM) waves. In the field of nonlinearity, second‐harmonic generation (SHG) is a research focus due to its diverse applications. There have been many researches for realizing SHG in optical regime using nonlinear characteristics of optical materials, but its efficiency is low. In microwave frequencies, SHGs are basically studied in the guided‐wave systems. Here, high‐efficiency SHGs of spatial waves are presented in the microwave frequency using nonlinear metasurface loaded with active chips at the subwavelength scale. The nonlinear meta‐atom is composed of receiving antenna, transmitting antenna, and active circuit of frequency multiplier, which can realize strongly nonlinear response and link the EM signals from the receiving to transmitting antennas. Correspondingly, to achieve the function of spatial‐wave frequency multiplication, the working frequency of the transmitting antenna in the meta‐atom should be twice as that of the receiving antenna, and hence the active chip is well matched to obtain the signal transforming with high efficiency. Good performance of the spatial‐wave frequency multiplication is demonstrated in the proof‐of‐concept experiments with the best transform efficiency of 85.11% under normal incidence, validating the proposed method.
Universal Strategy for Improving Perovskite Photodiode Performance: Interfacial Built‐In Electric Field Manipulated by Unintentional Doping
Authors: Wu Dan , Li Wenhui , Liu Haochen , Xiao Xiangtian , Shi Kanming , Tang Haodong , Shan Chengwei , Wang Kai , Sun Xiao Wei , Kyaw Aung Ko Ko
Published: July 2021

Organic–inorganic halide perovskites have demonstrated significant light detection potential, with a performance comparable to that of commercially available photodetectors. In this study, a general design guideline, which is applicable to both inverted and regular structures, is proposed for high‐performance perovskite photodiodes through an interfacial built‐in electric field (E) for efficient carrier separation and transport. The interfacial E generated at the interface between the active and charge transport layers far from the incident light is critical for effective charge carrier collection. The interfacial E can be modulated by unintentional doping of the perovskite, whose doping type and density can be easily controlled by the post‐annealing time and temperature. Employing the proposed design guideline, the inverted and regular perovskite photodiodes exhibit the external quantum efficiency of 83.51% and 76.5% and responsivities of 0.37 and 0.34 A W−1, respectively. In the self‐powered mode, the dark currents reach 7.95 × 10−11 and 1.47 × 10−8 A cm−2, providing high detectivities of 7.34 × 1013 and 4.96 × 1012 Jones, for inverted and regular structures, respectively, and a long‐term stability of at least 1600 h. This optimization strategy is compatible with existing materials and device structures and hence leads to substantial potential applications in perovskite‐based optoelectronic devices.
Anesthetic Propofol Promotes Tumor Metastasis in Lungs via GABAAR‐Dependent TRIM21 Modulation of Src Expression
Authors: Liu Qidong , Sheng Zhihao , Cheng Chun , Zheng Hui , Lanuti Michael , Liu Rong , Wang Ping , Shen Yuan , Xie Zhongcong
Published: July 2021

Generation of circulating tumor cells (CTCs), a key step in tumor metastasis, occurs during surgical tumor resection, often performed under general anesthesia. Propofol is the commonly used anesthetic, but its effects on CTCs and tumor metastasis remain largely unknown. Propofol effects are investigated in an experimental metastasis model by injecting tumor cells and, subsequently, low‐ or standard‐dose propofol to nude mice through tail vein. Propofol‐ or vehicle‐treated tumor cells are also injected to the mice. An in vitro tumor cell–vascular endothelial cell adhesion assay, immunofluorescence, and other methods are employed to assess how propofol affects tumor cell adhesion and extension. Propofol induces more lung tumor metastasis in mice than control. Mechanistically, propofol enhances tumor cell adhesion and extension through GABAAR to downregulate TRIM21 expression, leading to upregulation of Src, a protein associated with cell adhesion. These results demonstrate that propofol may promote tumor metastasis through GABAAR–TRIM21–Src mechanism.
A multi‐region and open‐source computational fluid dynamic tool for electrochemical systems with three‐dimensional electrodes
Authors: Colli Alejandro N. , Bisang José M.
Published: July 2021

In this work, a solver, implemented in OpenFOAM, is developed to investigate the mechanisms of ion transport through activated or resistive three‐dimensional (3D) electrodes, and also leakage currents in the case of a bipolar connection. The transport model, which accounts for the balance of mass, momentum, species, and electric charge in the fluid, 3D and solid phases, was solved using a multi‐region approach. The algorithm permits calculations for a fixed cell potential difference, and also for a current flowing through the cell under galvanostatic control. Analytical models and experimental results of the current and potential distribution are compared with the present tool, obtaining a close agreement between them. The model presented here is supplied as a free source code and can be employed to optimize both cell stack design and system operation conditions.
Validated international definition of the thrombocytopenia, anasarca, fever, reticulin fibrosis, renal insufficiency, and organomegaly clinical subtype (TAFRO) of idiopathic multicentric Castleman disease
Authors: Nishimura Yoshito , Fajgenbaum David C. , Pierson Sheila K. , Iwaki Noriko , Nishikori Asami , Kawano Mitsuhiro , Nakamura Naoya , Izutsu Koji , Takeuchi Kengo , Nishimura Midori Filiz , Maeda Yoshinobu , Otsuka Fumio , Yoshizaki Kazuyuki , Oksenhendler Eric , van Rhee Frits , Sato Yasuharu
Published: July 2021

Thrombocytopenia, anasarca, fever, reticulin fibrosis, renal insufficiency, and organomegaly (TAFRO) syndrome is a heterogeneous entity manifesting with a constellation of symptoms described above that can occur in the context of idiopathic multicentric Castleman disease (iMCD) as well as infectious diseases, malignancies, and rheumatologic disorders. So, iMCD‐TAFRO is an aggressive subtype of iMCD with TAFRO syndrome and often hyper‐vascularized lymph nodes. Since we proposed diagnostic criteria of iMCD‐TAFRO in 2016, we have accumulated new insights on the disorder and additional cases have been reported worldwide. In this systematic review and cohort analysis, we established and validated a definition for iMCD‐TAFRO. First, we searched PubMed and Japan Medical Abstracts Society databases using the keyword “TAFRO” to extract cases. Patients with possible systemic autoimmune diseases and hematologic malignancies were excluded. Our search identified 54 cases from 50 articles. We classified cases into three categories: (1) iMCD‐TAFRO (TAFRO syndrome with lymph node histopathology consistent with iMCD), (2) possible iMCD‐TAFRO (TAFRO syndrome with no lymph node biopsy performed and no other co‐morbidities), and (3) TAFRO without iMCD or other co‐morbidities (TAFRO syndrome with lymph node histopathology not consistent with iMCD or other comorbidities). Based on the findings, we propose an international definition requiring four clinical criteria (thrombocytopenia, anasarca, fever/hyperinflammatory status, organomegaly), renal dysfunction or characteristic bone marrow findings, and lymph node features consistent with iMCD. The definition was validated with an external cohort (the ACCELERATE Natural History Registry). The present international definition will facilitate a more precise and comprehensive approach to the diagnosis of iMCD‐TAFRO.
Discrete Self‐Assembled Metallo‐Foldamers with Heteroleptic Sequence Specificity
Authors: Preston Dan
Published: July 2021

Discrete and structurally diverse foldamer sequences are constructed in both natural and abiotic systems primarily using inert connectivity with irreversible organic covalent bonds, serving to preserve the identity of the sequence. The formation of sequences under thermodynamic control using labile coordination bonds would be attractive for synthetic ease and modular capability, but this presents issues regarding sequence preservation. Here is presented an approach integrating palladium(II) metal ions into the sequence itself, with fidelity maintained through use of complementary pairings of ligand arrangements at the metal centre. This is accomplished using sites of different denticity and/or hydrogen bonding capability. In this fashion, discrete and ordered metallo‐sequences are formed as thermodynamic products in a single step, and these then fold into defined conformations due to π–π interactions between electron‐rich and ‐poor aromatic regions of the combined componentry.
Revisiting a model to predict pure triglyceride thermodynamic properties: parameter optimization and performance
Authors: Seilert Julia , Moorthy Arun S. , Kearsley Anthony J. , Flöter Eckhard
Published: July 2021

In 1990, a well‐known model to predict pure component properties of triglycerides was presented by Wesdorp in “Liquid‐multiple solid phase equilibria in fats: theory and experiments” and has been shown to perform well despite making thermodynamically inconsistent predictions for certain test cases. In this study, the underlying parameter set is improved to deliver more physically consistent predictions, i.e., increasing melting point and enthalpy of fusion with increasing stability of the polymorphs, without deterioration of the primary model quality to describe the available experimental data. Interestingly, when a curated dataset containing only thermodynamically consistent data is compared to a broader dataset, it appears that the model's efficacy is highly dependent on the quantity of data, specifically the number of unsaturated triglycerides data. Quality and thermodynamic consistency of model predictions and the condition of a reliable description of monoacid triglycerides as a subset is discussed, addressing a potential interdependence.
Photoelectrochemical performance of tubewall‐separated titanium dioxide nanotube array photoelectrode
Authors: Xie Yibing
Published: July 2021

Titanium dioxide nanotube array (TiO2 NTA) grown on titanium substrate has been fabricated as active photoelectrode for organic compound degradation. TiO2 NTA shows the tubewall‐separated nanotube arrangement and anatase crystal structure. Transient photocurrent of 1.86 mA and open‐circuit photovoltage of 0.26 V are determined to keep stable level under ultraviolet (UV) light irradiation, indicating its high photoelectrochemical activity. The cathodic polarization process causes more feasible electron transfer than the equilibrium process and anodic polarization process, which is consistent with the declining current response at an increasing positive potential. The photocatalytic activity of TiO2 NTA is fully evaluated through UV light‐induced photocatalysis and photoelectrocatalysis degradation of organic dye X‐3B as a reactant pollutant. The pseudo‐first‐order reaction rate constant is enhanced from 0.00346 min−1 for photocatalysis to 0.00521 min−1 for photoelectrocatalysis using Langmuir–Hinshelwood kinetic model of heterogeneous catalysis. The tubewall‐separated nanotube structure could induce photoelectron directional transport and provide extra interspace for reactant organic molecule diffusion at accessible surface area. The positive potential applied on TiO2 NTA could further promote photoelectron–hole pair separation. Two strategies of photoelectron generation and photoelectron–hole separation are accordingly adopted to improve its electro‐assisted photocatalytic activity. Therefore, the tubewall‐separated TiO2 NTA could present the promising photoelectrocatalysis application.
Colonization history and human translocations explain the population genetic structure of the noble crayfish (Astacus astacus) in Fennoscandia: Implications for the management of a critically endangered species
Authors: Dannewitz Johan , Palm Stefan , Edsman Lennart
Published: July 2021

The noble crayfish (Astacus astacus) is an endangered freshwater species in Europe. The main threat is from lethal crayfish plague, caused by the oomycete Aphanomyces astaci that has been spread over Europe by introduced North American crayfish species, acting as chronic carriers of the disease.

Most of the remaining noble crayfish populations are found in the Baltic Sea area, and there is an urgent need to implement conservation actions to slow down or halt the extinction rate in this region. However, limited knowledge about the genetic structure of populations in this area has so far precluded the development of conservation strategies that take genetic aspects into consideration.

Key objectives of this large‐scale genetic study, covering 77 locations mainly from northern Europe, were to describe the contemporary population genetic structure of the noble crayfish in the Fennoscandian peninsula (Sweden, Norway, and Finland), taking postglacial colonization history into account, and to evaluate how human activities such as stocking have affected the genetic structure of the populations.

Analyses of 15 microsatellite markers revealed three main genetic clusters corresponding to populations in northern, middle, and southern Fennoscandia, with measures of genetic diversity being markedly higher within populations in the southern cluster. The observed genetic structure probably mirrors two main colonizations of the Baltic Sea basin after the last glaciation period. At the same time, several deviations from this pattern were observed, reflecting past human translocations of noble crayfish.

The results are discussed in relation to the conservation and management of this critically endangered species. In particular, we recommend increased efforts to protect the few remaining noble crayfish populations in southern Fennoscandia and the use of genetic information when planning stocking activities, such as reintroductions following local extinctions.
Taste receptors in aquatic mammals: Potential role of solitary chemosensory cells in immune responses
Authors: Barboza Meghan Lee Bills , Reyno Beau
Published: July 2021

The sense of taste is associated with the evaluation of food and other environmental parameters such as salinity. In aquatic mammals, anatomic and behavioral evidence of the use of taste varies by species and genomic analysis of taste receptors indicates an overall reduction and, in some cases, complete loss of intact bitter and sweet taste receptors. However, the receptors used by taste buds in the oral cavity are found on cells in other areas of the body and play an important role in immune responses. In the respiratory tract, an example of such cells is solitary chemosensory cells (SCCs) which have bitter and sweet taste receptors. The bitter receptors detect chemicals given off by pathogens and initiate an innate immune response. Although many aquatic mammals may not have a role for taste in the assessment of food, they likely would benefit from the added protection that SCCs provide, especially considering respiratory diseases are a problem for many aquatic mammals. While evidence indicates that some species do not possess functional bitter receptors for taste, many do have intact bitter receptor genes and it is important for researchers to be aware of all roles for these receptors in homeostasis. Through a better understanding of the anatomy and physiology of aquatic mammal's respiratory systems, better treatment and management is possible.
Adaptive fuzzy backstepping super‐twisting sliding mode control of nonlinear systems with unknown hysteresis
Authors: Li M. , Li Y. , Wang Q.
Published: July 2021

In this paper, an adaptive fuzzy backstepping super‐twisting sliding mode control (AFBSTSMC) scheme is proposed for a class of nonlinear systems with unknown hysteresis, unmeasured states, and external disturbances. First, fuzzy logic systems are employed to approximate the unknown nonlinear functions of the controlled systems, and a fuzzy state observer is designed to estimate the unmeasured states. Then, combining the backstepping technique and adaptive sliding mode control with super‐twisting algorithm, the AFBSTSMC scheme is proposed without constructing the hysteresis inverse. The problem of “explosion of complexity” inherent in the conventional backstepping design method is eliminated by utilizing the dynamic surface control technique. Moreover, the chattering phenomenon is significantly reduced by using the developed adaptive fuzzy super‐twisting controller. It is proved that the proposed control scheme can guarantee that all the signals in the closed‐loop system are semi‐globally ultimately uniformly bounded and the observer and tracking errors can converge to a small domain of the origin. Finally, the effectiveness of the presented control scheme is confirmed in two examples including a numerical simulation and an inverted pendulum with unknown hysteresis actuator.
Design of adaptive weld quality monitoring for multiple‐conditioned robotic welding tasks
Authors: Xia Suibo , Khiang Pang Chee , Al Mamun Abdullah , Seng Wong Fook , Meng Chew Chee
Published: July 2021

Multiple‐conditioned welding monitoring is a challenging issue in complex robotic welding tasks. In practice, the monitoring system has to be sensitive to different welding conditions (WCs) and weld quality changes. In this paper, a swing high temperature sensor system is used in order to obtain the temperature distribution curve under different WCs. A sigmoid feature extraction (SFE) method is proposed to obtain the geometric features of the temperature distribution curve, and a weld monitoring algorithm is proposed for multiple‐conditioned welding tasks using multi‐layer perceptron (MLP) classifier and Kalman filter‐based Gaussian probability density function (PDF) prediction for the probabilistic weld quality estimation. When there are unknown WCs, the proposed method uses an efficient incremental learning for the MLP and an online maximum likelihood estimation for the Gaussian models of the unknown WCs. The experimental results show that the proposed framework can accurately reflect the weld quality changing in both single‐WC and multiple‐WC tasks. In addition, the proposed adaptive updating methodology can achieve comparable performance with unknown WCs, as compared to the results with knowing all the WCs.
Fuzzy‐based adaptive event‐triggered control for switched stochastic nonlinear systems with state constraints
Authors: Liu Yongchao , Zhu Qidan
Published: July 2021

In this paper, a fuzzy‐based control strategy is devised for switched stochastic nonlinear systems with state constraints. All states are guaranteed to maintain the prescribed regions whereby barrier Lyapunov function. To mitigate the data transmission and save resource, the event‐triggered mechanism (ETM) is exploited to update control signal. To further deal with system uncertainties, the fuzzy logic systems are taken as function approximators. By combining the backstepping technique with event‐triggered mechanism, the adaptive fuzzy control (AFC) strategy is recursively established. In virtue of Lyapunov theory and average dwell time method (ADT), the devised AFC method can guarantee that the entire closed‐loop systems are uniformly bounded and the prescribed state constraints are not violated. Finally, the validity of the developed method is illustrated via a simulation example.
Effect of nutrient metabolism on cartilaginous tissue formation
Authors: Tarantino Roberto , Chiu Loraine L. Y. , Weber Joanna F. , Yat Tse Man , Bardana Davide D. , Pang Stephen C. , Waldman Stephen D.
Published: July 2021

A major shortcoming in cartilage tissue engineering is the low biosynthetic response of chondrocytes. While different strategies have been investigated, a novel approach may be to control nutrient metabolism. Although known for their anaerobic metabolism, chondrocytes are more synthetically active under conditions that elicit mixed aerobic–anaerobic metabolism. Here, we postulate this metabolic switch induces HIF‐1α signaling resulting in improved growth. Transition to different metabolic states can result in the pooling of metabolites, several of which can stabilize HIF‐1α by interfering with PHD2. Chondrocytes cultured under increased media availability accelerated tissue deposition with the greatest effect occurring at 2 ml/106 cells. Under higher media availability, metabolism switched from anaerobic to mixed aerobic‐anaerobic. Around this transition, maximal changes in PHD2 activity, HIF‐1α expression, and HIF‐1 target gene expression were observed. Loss‐of‐function studies using YC‐1 confirmed the involvement of HIF‐1. Lastly, targeted metabolomic studies revealed that intracellular lactate and succinate correlated with PHD2 activity. This study demonstrates that cartilaginous tissue formation can be regulated by nutrient metabolism and that this response is mediated through changes in HIF‐1α signaling. By harnessing this newly identified metabolic switch, engineered cartilage implants may be developed without the need for sophisticated methods which could aid translation to the clinic.
Ultrahigh‐cell‐density heterotrophic cultivation of the unicellular green alga Chlorella sorokiniana for biomass production
Authors: Jin Hu , Chuai Wenhua , Li Kunpeng , Hou Guoli , Wu Mingcan , Chen Jianping , Wang Hongxia , Jia Jing , Han Danxiang , Hu Qiang
Published: July 2021

Heterotrophic cultivation of Chlorella has achieved commercial success, but the application of Chlorella biomass is still limited due to the high cost of biomass production. In this study, an effective and industrially scalable heterotrphic cultivation technology has been developed for a production strain Chlorella sorokiniana GT‐1. Under the optimized culturing conditions, the ultrahigh biomass concentration of 271 and 247 g L−1 was achieved in 7.5 L bench‐scale and 1000 L pilot‐scale fermenters, respectively. Technoeconomic (TE) analysis indicated that the production cost of C. sorokiniana GT‐1 could be reduced to $1601.27 per ton of biomass if the biomass concentration reached 200 g L−1, which is 24.2% lower than that of the reported highest Chlorella biomass production through fermentation with the same TE model. Under the same growth conditions, the maximum biomass concentration of a low‐starch mutant SLM2 was reduced to 93 g L−1, which was 54% lower than that of the wild type, indicating the capabilities of C. sorokiniana GT‐1 cells in accumulating large amounts of starch are essential for achieving the ultrahigh‐cell‐density under the heterotrophic conditions. In addition, the ultrahigh‐cell‐density growth potential of C. sorokiniana GT‐1 cells was inferred to be related to the intrinsic biological characteristics including the tolerance to low dissolved oxygen and a moderate doubling time under the heterotrophic conditions as well. The breakthrough in cultivation technology is promising for Chlorella industry and would expand its applications in food and feed.
Growth mindset interventions improve academic performance but not mindset in biochemistry
Authors: Miller Heather B. , Srougi Melissa C.
Published: July 2021

Growing evidence suggests that students' self‐beliefs about altering their academic abilities can directly influence long‐term achievement. These self‐beliefs or mindsets can either be fixed (unchangeable) or growth oriented. Students with growth mindsets believe their academic abilities can change, which leads to higher grades and academic persistence in contrast to students with fixed mindsets. However, less is known about how these attributes affect student learning, particularly in college level biochemistry courses. In this study, we utilized metacognitive interventions to promote growth mindset among third and fourth year undergraduate students enrolled in a one semester Biochemistry survey course. Using a mixed‐methods study design, we evaluated student mindset, attitudes toward learning, and academic performance over four semesters. Our results suggest that although students' mindsets did not change as a result of growth mindset interventions, their positive perceptions about learning versus performance did increase. Furthermore, students receiving growth mindset interventions significantly outperformed students who did not receive interventions on the final cumulative exam that assessed critical thinking skills. These results suggest that these types of metacognitive interventions can be an effective tool to improve student academic performance in a biochemistry course.
Identification of a competing endogenous RNA axis “SVIL‐AS1/miR‐103a/ICE1” associated with chemoresistance in lung adenocarcinoma by comprehensive bioinformatics analysis
Authors: Guo Lili , Ding Lina , Tang Junfang
Published: July 2021

Background

Chemotherapy is an important treatment for lung cancer. The molecular mechanism of lung adenocarcinoma (LUAD) chemoresistance is not completely understood.

Methods

Weighted gene co‐expression network analysis (WGCNA) was applied to screen the modules related to chemosensitivity using the data of LUAD patients receiving chemotherapy in The Cancer Genome Atlas database. GDCRNATools package was used to establish competing endogenous RNA (ceRNA) network based on the key chemotherapy‐related module. Kaplan–Meier and risk models were used to analyze the influence of genes in the ceRNA network on the prognosis of LUAD patients receiving chemotherapy. Cell counting kit‐8, reverse transcription‐quantitative PCR, and dual‐luciferase reporter assay were used to detect the effects of abnormal expression of genes in the ceRNA network on the proliferation and IC50 of cisplatin (DDP)‐resistant LUAD cells, and the targeting relationship of genes in the ceRNA network. The signaling pathways and functions of ICE1 in LUAD were analyzed by LinkOmics and CancerSEA databases, and validated by Western blot.

Results

Midnightblue module was the only WGCNA module positively correlated with chemosensitivity, in which the function of genes was related to cancer progression. SVIL‐AS1/miR‐103a/ICE1 was constructed based on midnightblue module. High expression of SVIl‐AS1 and ICE1 corresponded to a favorable prognosis. High expression of miR‐103a corresponded to a dismal prognosis. SVIl‐AS1 was downregulated in DDP‐resistant LUAD cells. SVIL‐AS1 overexpression retarded the proliferation and DDP resistance of DDP‐resistant LUAD cell. miR‐103a was sponged by SVIL‐AS1 and directly targeted ICE1. miR‐103a overexpression and ICE1 knockdown overturned the suppressive effect of SVIL‐AS1 overexpression on cell proliferation and DDP resistance. Further bioinformatics analysis and experimental verification showed that SVIL‐AS1/miR‐103a‐3p/ICE1 axis can enhance DNA damage caused by chemotherapeutic agents.

Conclusions

SVIL‐AS1 inhibited chemoresistance by acting as a sponge for miR‐103a and upregulating ICE1 expression, which may be a potential therapeutic target for chemotherapy in LUAD.
The effect of AI quality on customer experience and brand relationship
Authors: Nguyen Tuyet‐Mai , Quach Sara , Thaichon Patamaporn
Published: July 2021

Although Artificial Intelligence (AI) has been gradually introduced to various industries, research on customer attitudes and behavior toward the use of AI is still in its infancy. Underpinned by flow theory and social identity theory, the current research aims to examine the influence of AI on the customer experience of flow, customer‐brand identification and customer advocacy. In addition, it is suggested that employee responsiveness moderates the effect of AI quality on flow and customer‐brand identification. A paper‐based survey was used to collect data from 350 guests from hotels in Vietnam. The findings indicate that AI information currency and system flexibility are significantly related to flow whereas AI system timeliness is the only dimension that significantly affects customer‐brand identification. Flow and customer‐brand identification significantly mediates the relationship between AI quality and customer advocacy. Besides, as the level of employee responsiveness decreases, the effect of AI system reliability on customer‐brand identification is more significant. This study extends the current body of knowledge in relation to the role of AI in the development of service experience and the relationship between customers and an organization. The findings make a compelling case for hotels to invest in AI tools in order to respond to customer expectations and improve their perception of hotel services.