bluuebunny/crossref_metadata_2025 huggingface dataset:
Effects of vegetation restoration on distribution characteristics of heavy metals in soil in Karst plateau area of Guizhou
Authors: Wu Yunjie , Tian Xin , Wang Runze , Zhang Mingyi , Wang Shuo
Published: March 2023

In southwest China, vegetation restoration is widely used in karst rocky desertification control projects. This technology can effectively fix the easily lost soil, gradually restore the plant community and improve soil fertility. However, the change law of soil heavy metals in the restoration process remains to be further studied. Therefore, in this work, Guizhou Caohai Nature Reserve as a typical karst area was taken as the research object to investigate the influence of vegetation restoration technology on repairing soil heavy metal pollution. The spatial distribution characteristics of soil heavy metals (chromium, nickel, arsenic, zinc, lead) before and after vegetation restoration in karst area were studied by comparative analysis and linear stepwise regression analysis. The main influencing factors and spatial distribution characteristics of heavy metals in karst area were further discussed. The results showed that: (1) heavy metals in karst soils are affected by surface vegetation, root exudates, microorganisms and leaching. Only heavy metals nickel (Ni) and lead (Pb) showed the tendency of surface enrichment and bottom precipitation enrichment in non-karst soils. Path analysis suggested that non-metallic soil factors such as soil bulk density (BD), total nitrogen (TN) and ammonium nitrogen (NH4+-N) had direct effect on the content of heavy metals in soil. (2) The proportion of 0.25–2 mm aggregates in the surface soil of vegetation restoration belt was more than 40%, and the proportion of surface soil ≤2 mm aggregates in this increased to 83% and 88%, respectively, which could improve the soil structure and properties effectively. (3) Vegetation restoration effectively restored the nutrient elements such as carbon and nitrogen in the soil, and enhanced the soil material circulation. Furthermore the content of heavy metals in the surface soil higher than that in the 10–20 cm soil layer. Plant absorption, biosorption mechanism of microorganisms, coupling of root exudates, dissolution of soil soluble organic carbon and pH make the contents of heavy metals Cr, Ni and Pb in vegetation restoration belt slightly lower than those in karst soil. At the same time, affected by vegetation coverage, residual heavy metals in soil are further leached by surface runoff. Therefore, the content of heavy metals in soil could reduce combined heavy metal enrichment plants for extraction with remediation. This study elucidates the advantages and remedy mechanism of vegetation restoration in the remediation of heavy metal contaminated soils in Caohai area of Guizhou, and this plant activation and enrichment extraction remediation technology would be popularized and applied in the remediation of heavy metal contaminated soils in other karst areas.
Ferroptosis-dependent breast cancer cell-derived exosomes inhibit migration and invasion of breast cancer cells by suppressing M2 macrophage polarization
Authors: Yi Chenghao , Wu Shilong , Duan Qianyu , Liu Lei , Li Li , Luo Yonghui , Wang Anan
Published: March 2023

Aim

Ferroptosis, a novel type of iron-dependent cell death, plays a vital role in breast cancer progression. However, the function of ferroptosis-induced cancer cell-derived exosomes in breast cancer remains unclear. In this study, we attempted to investigate the impact of breast cancer cells-derived exosomes induced by ferroptosis on the polarization of macrophages and the progression of breast cancer.

Methods

Erastin was used to induce ferroptosis and breast cancer cell-derived exosomes were identified by transmission electron microscopy. Western blot, quantitative reverse transcription PCR, immunofluorescence, flow cytometry, and ELISA were used to determine the role of exosomes in macrophage polarization. Transwell assays were used to detect breast cancer cell migration, and invasion.

Results

Our results showed that erastin promoted ferroptosis in breast cancer cells with increased Fe2+ level and ROS production. Breast cancer cell-derived exosomes induced by ferroptosis were successfully isolated and verified to be internalized by macrophages. In addition, ferroptosis-induced breast cancer cell-derived exosomes (Fe-exo) remarkably diminished M2 marker, Arg-1 expression. The ratio of CD206+ macrophages was significantly decreased after Fe-exo treatment. CD206 protein expression and Arg-1 level were dramatically reduced in M2 macrophages incubated by Fe-exo. Moreover, autophagy PCR array showed that the expression of 84 autophagy-related genes were altered after macrophages were incubated by Fe-exo. Furthermore, macrophages incubated by Fe-exo repressed the migration and invasion of breast cancer cells.

Conclusion

Ferroptosis-dependent cancer cell-derived exosomes inhibited M2 polarization of macrophages, which in turn inhibited migration and invasion of breast cancer cells. This study provides novel therapeutic strategies for patients with breast cancer.
Spatial Variability in Soil Properties, Delineation Site-specific Management Division Based on Soil Fertility Using Fuzzy Clustering in Gwalior, Madhya Pradesh, India
Authors: Yadav T. C. , Singh Y. P. , Yadav Shashi S. , Singh Akhilesh , Subhash  , Patle Tirunima
Published: March 2023

Farmers who want to improve nitrogen usage efficiency (NUE) and crop yield must have access to information regarding the geographical variability and distribution of soil parameters. Fertilizer application relying on soil characteristic maps and fertilizers recommendations may help reduce fertilizer input without sacrificing crop production. The current research focused heavily on evaluating the variability of soil fertility status in the Madhya Pradesh Gwalior region using geostatistical techniques. To do this, 150 GPS-based surfaces (0–15 cm) soil samples were obtained from the Gwalior region's five districts (Gwalior, Shivpuri, Datia, Guna, & Ashok Nagar) during crop harvest during the rabi season of 2019–20. Statistics and geo-statistics were used to analyze the results of the laboratory analysis. The analysis revealed that the soil samples' pH, EC, SOC, and CaCO3 values, respectively, varied from 4.40 to 8.30, 0.09 to 1.03 dSm-1, 2.0 to 10.60 gkg-1, and 3.0 to 24.0 gkg-1. In contrast, the amounts of N, P, K, and S that are present in soil vary from 102.0 to 356.0 kg ha-1, 6.0 to 61.0 kg ha-1, 114.0 to 896.0 kg ha-1, and 5.90 to 49.20 mg kg-1, respectively.

Through building semi-variograms and mapping the data utilizing standard kriging techniques, the information was studied using both traditional statistics and geostatistics. For soil properties, semi-variograms were created, and their geographical distributions were delineated. The Nugget/Sill (Co/Co+ C) ratio for the modeled variables revealed moderate to high spatial dependences. The best-fit models for the reported soil characteristics were exponential, spherical, and circular. The findings of this research demonstrated that soil fertility quality varied significantly across the Gwalior area. This knowledge may aid in making choices about crop succession and the usage of plant nutrients to increase farmers' financial returns.
RAND: Cross‐system innovation essential to curb epidemic of fatal overdoses
Authors: Enos Gary
Published: March 2023

Making more high‐quality treatment available for individuals with substance use disorders (SUDs) might be a top priority, but it will not in and of itself stem the tide of overdose deaths in the U.S., a new report suggests. The RAND Corporation's comprehensive report states that policymakers must embrace novel, even unconventional, strategies that acknowledge the effects that an initiative in one system can have on outcomes in another.
Magnetic Control of Vibrational Behavior of Smart FG Sandwich Plates with Honeycomb Core via a Quasi‐3D Plate Theory
Authors: Sobhy Mohammed , Al Mukahal Fatemah. H. H.
Published: March 2023

Herein, vibrational behavior of functionally graded (FG) smart piezoelectric sandwich plates with honeycomb core resting on viscoelastic foundation under the effect of 2D magnetic field is presented. By varying the magnetic‐field magnitude and its direction, the vibrations can be controlled. The plate is composed of two FG piezoelectric layers bonded with honeycomb structure as a mid‐layer. Magnetic Lorentz force will be deduced via Maxwell's relations. A new quasi‐3D plate theory considering the shear and normal deformations is incorporated to evaluate the displacements. The governing equations of motion are introduced via Hamilton's principle. Galerkin technique is considered to solve the motion equations for different boundary conditions. Influences of the magnetic field, boundary conditions, electric voltage, and core thickness on the eigenfrequency of the FG sandwich piezoelectric plate are illustrated. It is found that considering the effect of the magnetic field on the smart devices increases their vibrations, which may lead to an increment in the energy harvested from them. Further, when the magnetic field is applied along the length of the rectangular plate, the vibrations are reduced and vice versa.
A Novel Multifunctional Photocatalytic Separation Membrane Based on Single‐Component Seaweed‐Like g‐C3N4
Authors: Li Liuxin , Luo Chunjia , Chen Xushuai , Chu Na , Li Le , Chao Min , Yan Luke
Published: March 2023

Multifunctional separation membrane is usually realized by multi‐component collaborative construction, which makes the membrane preparation method complicated and uncontrollable. Herein, a novel multifunctional photocatalytic separation membrane is prepared by vacuum self‐assembly of single seaweed‐like g‐C3N4 photocatalyst. The seaweed‐like g‐C3N4 gives membrane certain roughness, large specific surface area, excellent hydrophilicity and abundant transport channels. Through a systematic study, the membrane exhibits excellent separation of five oil‐in‐water emulsions with a maximum flux of 3114.0 ± 113.0 L m−2 h−1 bar−1 for 1, 2‐dichloroethane‐in‐water (Dc/W) emulsion and a maximum efficiency of 97.4 ± 0.1% for chloroform‐in‐water (C/W) emulsion. In addition, the seaweed‐like g‐C3N4 with large specific surface area and narrow bandgap render excellent visible light absorption characteristics and accelerate e−‐h+ pairs transport rate, giving the membrane excellent photocatalytic degradation and antibacterial properties. The membrane shows good degradation for eight different pollutants, among which the degradation effect for rhodamine B (RhB), methylene blue (MB), and crystal violet (CV) were ≈100%. The antibacterial efficiency against E. coli and S. aureus is also close to 100%. After 35 consecutive separations of C/W emulsion and 10 consecutive degradations of RhB, the membrane still maintains excellent separation performance. This long‐lasting multifunctional separation membrane exhibits broad application prospects in complex wastewater purification.
3D Printing Thermally Stable High‐Performance Polymers Based on a Dual Curing Mechanism
Authors: Binyamin Iris , Grossman Eitan , Gorodnitsky Matanel , Kam Doron , Magdassi Shlomo
Published: March 2023

High‐performance polymers are an important class of materials that are used in challenging conditions, such as in aerospace applications. Until now, 3D printing based on stereolithography processes can not be performed due to a lack of suitable materials. There is report on new materials and printing compositions that enable 3D printing of objects having extremely high thermal resistance, with Tg of 283 °C and excellent mechanical properties. The printing is performed by a low‐cost Digital Light Processing printer, and the formulation is based on a dual‐cure mechanism, photo, and thermal process. The main components are a molecule that has both epoxy and acrylate groups, alkylated melamine that enables a high degree of crosslinking, and a soluble precursor of silica. The resulting objects are made of hybrid materials, in which the silicon is present in the polymeric backbone and partly as silica enforcement particles.
Ultrafast Shape‐Reconfigurable Chiral Mechanical Metamaterial based on Prestressed Bistable Shells
Authors: Liu Yizhe , Pan Fei , Xiong Feng , Wei Yuling , Ruan Yicheng , Ding Bin , Yang Kuijian , Chen Yuli
Published: March 2023

Fast shape‐reconfiguration with large morphing amplitude is crucial for intelligent materials/structures that require tunable functions and adaptivity to different environments. However, the morphing strategies are rare in combining ultrafast speed, large amplitude, and high energy‐efficiency simultaneously. Herein, a class of 2D and 3D chiral mechanical metamaterials are proposed to tackle this challenge based on prestressed bistable metallic shells. The metamaterial is architected by cylindrical cores and slender bistable shells with an anti‐chiral arrangement. The bistable shell has a flat extended shape and a rolled‐up shape that can wrap on the connected cylindrical cores compatibly, and thus endow the metamaterials with a tunable morphing amplitude that can even extend to infinity. By experiments, simulations and theoretical modelling, it is demonstrated that the bistable shell can transform from the extended state to the rolled‐up state with a transitional speed of 7.56 m s−1, which provides the 2D and 3D metamaterials with 25.38‐ and 101.14‐times body area/volume variation per second, respectively. Moreover, a smart trapper for capturing moving objects and a phononic structure with tunable band gaps are realized based on the metamaterials. This work provides a straightforward platform to design metamaterials and their derived systems with ultrafast and large‐amplitude shape‐reconfigurability.
Poly(dimethylsiloxane)‐block‐PM6 Polymer Donors for High‐Performance and Mechanically Robust Polymer Solar Cells
Authors: Seo Soodeok , Lee Jin‐Woo , Kim Dong Jun , Lee Dongchan , Phan Tan Ngoc‐Lan , Park Jinseok , Tan Zhengping , Cho Shinuk , Kim Taek‐Soo , Kim Bumjoon J.
Published: March 2023

High power conversion efficiency (PCE) and stretchability are the dual requirements for the wearable application of polymer solar cells (PSCs). However, most efficient photoactive films are mechanically brittle. In this work, highly efficient (PCE = 18%) and mechanically robust (crack‐onset strain (COS) = 18%) PSCs are acheived by designing block copolymer (BCP) donors, PM6‐b‐PDMSx (x = 5k, 12k, and 19k). In these BCP donors, stretchable poly(dimethylsiloxane) (PDMS) blocks are covalently linked with the PM6 blocks to effectively increase the stretchability. The stretchability of the BCP donors increases with a longer PDMS block, and PM6‐b‐PDMS19k:L8‐BO PSC exhibits a high PCE (18%) and 9‐times higher COS value (18%) compared to that (COS = 2%) of the PM6:L8‐BO‐based PSC. However, the PM6:L8‐BO:PDMS12k ternary blend shows inferior PCE (5%) and COS (1%) due to the macrophase separation between PDMS and active components. In the intrinsically stretchable PSC, the PM6‐b‐PDMS19k:L8‐BO blend exhibits significantly greater mechanical stability PCE80% ((80% of the initial PCE) at 36% strain) than those of the PM6:L8‐BO blend (PCE80% at 12% strain) and the PM6:L8‐BO:PDMS ternary blend (PCE80% at 4% strain). This study suggests an effective design strategy of BCP PD to achieve stretchable and efficient PSCs.
Biocompatible Film‐Coating of Magnetic Soft Robots for Mucoadhesive Locomotion
Authors: Wang Chen , Mzyk Aldona , Schirhagl Romana , Misra Sarthak , Venkiteswaran Venkatsubramanian Kalpathy
Published: March 2023

Magnetically‐actuated soft robots for medical applications are required to be functional, biocompatible, as well as capable of robust motion inside human organs. In this paper, a ring‐shaped magnetic soft robot, with a flexible biopolymeric film coating, capable of motion on mucus‐coated surfaces is designed and investigated. The biopolymeric film made from chitosan–glycerol (C–G) solution endows the robot with robust locomotion capabilities on surfaces of diverse geometrical shapes and orientations. By utilizing mucoadhesive locomotion, the robot has the potential to carry out clinical procedures on enclosed mucus‐coated tissue surfaces. Material characterization shows that the mucoadhesion increases with the increase of contact times and/or preload forces. The softness of the C–G film can be adjusted by controlling the concentration of glycerol. The ring‐shaped design and magnetization profile decouple the locomotion and functions of the robot. Additionally, the C–G film‐coated robot is tested to be biocompatible for a human colorectal adenocarcinoma cell line with epithelial morphology (HT29). The C–G film reduces the negative effects (superoxide generation) of ferromagnetic particles. Three robot functions including pick‐and‐place, cargo transportation, and liquid capsule release are demonstrated on different surfaces to show the maneuverability, functionality, and potential of implementing clinical procedures through mucoadhesion.
Altering the Atomic Order in Nanosized CHA Zeolites by Postsynthetic Silylation Treatment
Authors: Ghojavand Sajjad , Dib Eddy , Riodent Baptiste , Magisson Aymeric , Ruaux Valérie , Mintova Svetlana
Published: March 2023

In this work, a new post‐synthetic hydrothermal approach leading to simultaneous dealumination and silylation of zeolite nanocrystals is presented. Starting from a nanosized chabazite (CHA) type zeolite with a Si/Al ratio equal to 2, a set of samples with Si/Al ratios up to 4 are obtained by altering the acidity and concentration of the added silica modifier during the post‐synthesis treatment leading to concurrent dealumination and silylation. The effect of the acidity during the post‐synthetic silylation treatment at different pH of 1.0–8.5 at a constant silicon concentration is investigated. The nanosized CHA samples are characterized in details by Fourier transform infrared spectroscopy and NMR spectroscopy (1H, 29Si, 27Al), X‐ray diffraction, and thermogravimetric analyses. The post‐synthesis approach reported here can be applied to other zeolite types for fine‐tuning of their structural features including type and location of T‐atoms, silanol sites, and active sites.
Plasma‐Activated Hydrogels for Microbial Disinfection
Authors: Chen Jinkun , Wang Zifeng , Sun Jiachen , Zhou Renwu , Guo Li , Zhang Hao , Liu Dingxin , Rong Mingzhe , Ostrikov Kostya (Ken)
Published: March 2023

A continuous risk from microbial infections poses a major environmental and public health challenge. As an emerging strategy for inhibiting bacterial infections, plasma‐activated water (PAW) has proved to be highly effective, environmental‐friendly, and non‐drug resistant to a broad range of microorganisms. However, the relatively short lifetime of reactive oxygen and nitrogen species (RONS) and the high spreadability of liquid PAW inevitably limit its real‐life applications. In this study, plasma‐activated hydrogel (PAH) is developed to act as reactive species carrier that allow good storage and controlled slow‐release of RONS to achieve long‐term antibacterial effects. Three hydrogel materials, including hydroxyethyl cellulose (HEC), carbomer 940 (Carbomer), and acryloyldimethylammonium taurate/VP copolymer (AVC) are selected, and their antibacterial performances under different plasma activation conditions are investigated. It is shown that the composition of the gels plays the key role in determining their biochemical functions after the plasma activation. The antimicrobial performance of AVC is much better than that of PAW and the other two hydrogels, along with the excellent stability to maintain the antimicrobial activity for more than 14 days. The revealed mechanism of the antibacterial ability of the PAH identifies the unique combination of short‐lived species (1O2, ∙OH, ONOO− and O2−) stored in hydrogels. Overall, this study demonstrates the efficacy and reveals the mechanisms of the PAH as an effective and long‐term disinfectant capable of delivering and preserving antibacterial chemistries for biomedical applications.
Re‐evaluation of the economic threshold for Crocidosema aporema injury to indeterminate Bt soybean cultivars
Authors: Hayashida Rafael , Hoback Willian Wyatt , Dourado Patrick Marques , Bueno Adeney de Freitas
Published: March 2023

The neotropical soybean budborer (Crocidosema aporema [Walsingham, 1914] [Lepidoptera: Tortricidae]) is classified as a major pest of soybean that is difficult to manage with insecticides because larvae cause leaf‐rolling and can bore into the stem. Genetically modified Bt (Bacillus thuringiensis) soybean has been effective in managing C. aporema populations until recently when resistance has emerged and high infestation rates have been observed in Brazilian Bt soybean fields expressing Cry1Ac. The economic threshold (ET) for C. aporema was previously studied only in conventional (non‐Bt) determinate varieties of soybean. The present work evaluated the potential of C. aporema to injure indeterminate Bt soybean cultivars in two independent field trials carried out in 2020–2021 and 2021–2022 growing seasons. One field trial compared the response of individual injured and noninjured plants in the same field. The number of pods per plant, number of seeds per plant, and seed mass per plant in 12 of 13 trials were similar. In the second field trial, areas with and without insecticide applications were compared. There was a reduction in C. aporema damage after three insecticide applications, but yields were similar between treatments. Based on these results, C. aporema had low potential to cause economic injury to indeterminant Bt soybean cultivars. Thus, the current ET for C. aporema of 25%–30% of infested plants can be increased to 50%.
Total Synthesis of Diverse Tetramic Acid Bearing cis‐Decalin Natural Products
Authors: Dong Haoran , Hu Dachao , Hong Benke , Wang Jin , Lei Xiaoguang
Published: March 2023

We report herein the first total syntheses of four natural antibiotics, vermisporin, PF1052/AB4015‐A, AB4015‐L, AB4015‐B, and one hydrogenated natural product derivative, AB4015‐A2, that all feature a tetramic acid bearing cis‐decalin ring. The construction of the functionalized cis‐decalin ring was achieved by a diastereoselective intramolecular Diels‐Alder (IMDA) reaction, which proceeded via a rare endo‐boat transition state. Through an intramolecular neighboring‐group‐oriented strategy, the sterically hindered epoxy group in vermisporin, PF1052/AB4015‐A and AB4015‐L was installed efficiently. A one‐pot aminolysis/Dieckmann condensation cascade using l‐amino acid derivatives afforded the desired tetramic acid structure. The total synthesis led to the unambiguous verification of the absolute configuration of these natural products.
Collective Total Synthesis of Mavacuran Alkaloids through Intermolecular 1,4‐Addition of an Organolithium Reagent**
Authors: Mauger Audrey , Jarret Maxime , Tap Aurélien , Perrin Rémi , Guillot Régis , Kouklovsky Cyrille , Gandon Vincent , Vincent Guillaume
Published: March 2023

We report a synthetic endeavor towards the highly strained pentacyclic caged framework of the mavacuran alkaloids which culminated with the concise total synthesis of C‐fluorocurine, C‐profluorocurine, C‐mavacurine, normavacurine, 16‐epi‐pleiocarpamine and taberdivarine H. We designed a strategy involving late‐stage construction of the D ring by Michael addition of a vinylic nucleophile to a 2‐indolyl acrylate moiety. While the intramolecular Michael addition did not succeed, we were able to perform a diastereoselective unusual intermolecular 1,4‐addition of a functionalized vinyl lithium reagent to a readily accessible Michael acceptor with the assistance of the piperidine nitrogen atom through the formation of a complex as suggested by DFT computations. Final cyclization was achieved by nucleophilic substitution to form an ammonium intermediate. The first total syntheses of C‐profluorocurine and C‐fluorocurine were finalized by the dihydroxylation of C‐mavacurine and a pinacol rearrangement, respectively.
Modulating Triplet Excited States of Organic Semiconductors via Tuning Molecular Conformation for Dual‐ratiometric Thermometers
Authors: Chen Hao , Sun Yishuo , Liu Meihui , Li Fuyou , Peng Qian , Huang Hui
Published: March 2023

The dual‐ratiometric thermometry is one of highly accurate methods for microscopic thermal measurement in biological systems. Herein, a series of chromone derivatives with noncovalently intramolecular interactions (NIIs) were designed and synthesized for ratiometric thermometers. The triplet states of these organic compounds were systematically tuned upon regulating the conformation with NIIs to yield efficient room temperature phosphorescence and large wavelength difference between fluorescence and phosphorescence simultaneously. As a result, an unprecedent organic 3D dual‐ratiometric thermometer was established based on the intensity ratio and lifetime ratio of fluorescence/phosphorescence vs temperature, which was used for in vitro and in vivo bio‐thermometry with high accuracy. This work provides a novel method to achieve organic dual ratiometric thermometers via tuning the triplet excited states.
Photocatalytic conversion of MB dye using Co3O4 QDs‐Ag2MoO4 as an active heterojunction photocatalyst under visible light irradiation
Authors: Ghobadifard Mahdieh , Foroomand Shilan , Mohebbi Sajjad
Published: March 2023

Herein, the preparation of Co3O4 QDs‐Ag2MoO4 (AMO) heterojunction was reported by a facile hydrothermal method and characterized by physicochemical methods such as Fourier transformed infrared (FT‐IR), X‐ray diffraction (XRD), field emission scanning electron microscopy (FE‐SEM), energy‐dispersive X‐ray spectroscopy (EDS), transmission electron microscopy (TEM), differential reflectance spectroscopy (DRS), photoluminescence spectroscopy (PL), and UV–Vis. The SEM images show that AMO particles and Co3O4 QDs‐AMO have a morphology of 3D‐hexagons and nanosheets accumulated on the surface of 3D‐hexagons with an average of 36 and 28 nm in size, respectively. The Co3O4 QDs‐AMO photocatalyst was used toward the conversion of methylene blue with a removal percentage of 91%, which is 15 times more than pure AMO. The higher photoactivity of Co3O4 QDs‐AMO heterojunction should be assigned to its lower charge recombination rate compared with pure AMO nanoparticles. This heterojunction photocatalyst was removed from the mixture reaction and reused five times without a considerable decline in activity. Furthermore, a postulated mechanism by the hydroxyl radical (°OH) path was proposed.
Deep learning and differential equations for modeling changes in individual‐level latent dynamics between observation periods
Authors: Köber Göran , Kalisch Raffael , Puhlmann Lara M.C. , Chmitorz Andrea , Schick Anita , Binder Harald
Published: March 2023

When modeling longitudinal biomedical data, often dimensionality reduction as well as dynamic modeling in the resulting latent representation is needed. This can be achieved by artificial neural networks for dimension reduction and differential equations for dynamic modeling of individual‐level trajectories. However, such approaches so far assume that parameters of individual‐level dynamics are constant throughout the observation period. Motivated by an application from psychological resilience research, we propose an extension where different sets of differential equation parameters are allowed for observation subperiods. Still, estimation for intra‐individual subperiods is coupled for being able to fit the model also with a relatively small dataset. We subsequently derive prediction targets from individual dynamic models of resilience in the application. These serve as outcomes for predicting resilience from characteristics of individuals, measured at baseline and a follow‐up time point, and selecting a small set of important predictors. Our approach is seen to successfully identify individual‐level parameters of dynamic models that allow to stably select predictors, that is, resilience factors. Furthermore, we can identify those characteristics of individuals that are the most promising for updates at follow‐up, which might inform future study design. This underlines the usefulness of our proposed deep dynamic modeling approach with changes in parameters between observation subperiods.
Luminescence investigation of CaY2Al4SiO12:Dy3+ phosphor synthesized by sol–gel method
Authors: Verma Anita , Sharma Ravi , Bisen Durga Prasad , Brahme Nameeta , Thakkar Kamlesh , Tigga Shalinta , Chandrakar Priya
Published: March 2023

Dy3+‐doped CaY2Al4SiO12 phosphors were prepared using the sol–gel method. X‐ray diffraction (XRD), field emission scanning electron microscopy (FESEM), and energy dispersive spectroscopy analyses (EDS) were used to analyse the crystal structure, morphology, and elemental composition of the prepared samples. The luminescence behaviour of the sample was investigated using photoluminescence (PL) and thermoluminescence (TL) techniques. The prepared CaY2Al4SiO12:xDy3+ phosphor showed a characteristic blue and yellow emission at ~480 and 583 nm, respectively, with an excitation wavelength of 350 nm. The most intense PL emission was found for a 4 mol% doping concentration of Dy3+ ions. The CIE diagram of the phosphor showed bluish‐white colour emission. For TL studies, the prepared phosphors were irradiated with a 60Co γ (gamma) source and the TL glow curve of the CaY2Al4SiO12:0.04Dy3+ phosphor showed three overlapped peaks. For the Gaussian peaks, Chen's peak shape method was applied to determine the kinetic parameters of the samples.
Minimal purification method enables developability assessment of recombinant proteins
Authors: Rodriguez‐Aponte Sergio A. , Naranjo Christopher A. , Johnston Ryan S. , Dalvie Neil C. , Crowell Laura E. , Bajoria Sakshi , Kumru Ozan S. , Joshi Sangeeta B. , Volkin David B. , Love J. Christopher
Published: March 2023

Analytical characterization of proteins is a critical task for developing therapeutics and subunit vaccine candidates. Assessing candidates with a battery of biophysical assays can inform the selection of one that exhibits properties consistent with a given target product profile (TPP). Such assessments, however, require several milligrams of purified protein, and ideal assessments of the physicochemical attributes of the proteins should not include unnatural modifications like peptide tags for purification. Here, we describe a fast two‐stage minimal purification process for recombinant proteins secreted by the yeast host Komagataella phaffii from a 20 mL culture supernatant. This method comprises a buffer exchange and filtration with a Q‐membrane filter and we demonstrate sufficient removal of key supernatant impurities including host‐cell proteins (HCPs) and DNA with yields of 1–2 mg and >60% purity. This degree of purity enables characterizing the resulting proteins using affinity binding, mass spectrometry, and differential scanning calorimetry. We first evaluated this method to purify an engineered SARS‐CoV‐2 subunit protein antigen and compared the purified protein to a conventional two‐step chromatographic process. We then applied this method to compare several SARS‐CoV‐2 RBD sequences. Finally, we show this simple process can be applied to a range of other proteins, including a single‐domain antibody, a rotavirus protein subunit, and a human growth hormone. This simple and fast developability methodology obviates the need for genetic tagging or full chromatographic development when assessing and comparing early‐stage protein therapeutics and vaccine candidates produced in K. phaffii.
Long‐term follow‐up seizure outcomes after corpus callosotomy: A systematic review with meta‐analysis
Authors: Wu Xiaolong , Ou Siqi , Zhang Huaqiang , Zhen Yuhang , Huang Yinchun , Wei Penghu , Shan Yongzhi
Published: March 2023

Background

Corpus callosotomy (CC) is appropriate for patients with seizures of a bilateral or diffuse origin, or those with seizures of a unilateral origin with rapid spread to the contralateral cerebral hemisphere. The efficiency of CC in patients with drug‐resistant epilepsy is a long‐term concern because most articles reporting the surgical results of CC arise from small case series, and the durations of follow‐up vary.

Methods

PubMed, Embase, Cochrane Library, and Web of Science were searched to identify papers published before November 8, 2021. The systematic review was completed following PRISMA guidelines. Outcomes were analyzed by meta‐analysis of the proportions.

Results

A total of 1644 patients with drug‐resistant epilepsy (49 retrospective or prospective case series studies) underwent CC, and the follow‐up time of all patients was at least 1 year. The rate of complete seizure freedom (SF) was 12.38% (95% confidence interval [CI], 8.17%–17.21%). Meanwhile, the rate of complete SF from drop attacks was 61.86% (95% CI, 51.87%–71.41%). The rates of complete SF after total corpus callosotomy (TCC) and anterior corpus callosotomy (ACC) were 11.41% (95% CI, 5.33%–18.91%) and 6.75% (95% CI, 2.76%–11.85%), respectively. Additionally, the rate of complete SF from drop attacks after TCC was significantly higher than that after ACC (71.52%, 95% CI, 54.22%–86.35% vs. 57.11%, 95% CI, 42.17%–71.49%). The quality of evidence for the three outcomes by GRADE assessment was low to moderate.

Conclusion

There was no significant difference in the rate of complete SF between TCC and ACC. TCC had a significantly higher rate of complete SF from drop attacks than did ACC. Furthermore, CC for the treatment of drug‐resistant epilepsy remains an important problem for further investigation because there are no universally accepted standardized guidelines for the extent of CC and its benefit to patients. In future research, we will focus on this issue.
Acid sphingomyelinase (ASM) and COVID‐19: A review of the potential use of ASM inhibitors against SARS‐CoV‐2
Authors: Pauletto Pedro José Tronco , Delgado Cassia Pereira , da Rocha João Batista Teixeira
Published: March 2023

In the last 2 years, different pharmacological agents have been indicated as potential inhibitors of SARS‐CoV‐2 in vitro. Specifically, drugs termed as functional inhibitors of acid sphingomyelinase (FIASMAs) have proved to inhibit the SARS‐CoV‐2 replication using different types of cells. Those therapeutic agents share several chemical structure characteristics and some well‐known representatives are fluoxetine, escitalopram, fluvoxamine, and others. Most of the FIASMAs are primarily used as effective therapeutic agents to treat different pathologies, therefore, they are natural drug candidates for repositioning strategy. In this review, we summarize the two main proposed mechanisms mediating acid sphingomyelinase (ASM) inhibition and how they can explain the inhibition of SARS‐CoV‐2 replication by FIASMAs. The first mechanism implies a disruption in the lysosomal pH fall as the endosome–lysosome moves toward the interior of the cell. In fact, changes in cholesterol levels in endosome–lysosome membranes, which are associated with ASM inhibition is thought to be mediated by lysosomal proton pump (ATP‐ase) inactivation. The second mechanism involves the formation of an extracellular ceramide‐rich domain, which is blocked by FIASMAs. The ceramide‐rich domains are believed to facilitate the SARS‐CoV‐2 entrance into the host cells.
Mechanocatalysis: Simple and Rapid Mechanochemical Synthesis of Ammonia in Hydrogen, Nitrogen, and Water System
Authors: He Chengli , Hao Zixiang , Wang Linrui , Qiu Dong , Wang Mingyan , Chen Yang , Cui Xiaoli
Published: March 2023

Mechanical force‐induced N2 fixation is an emerging strategy for single‐step ammonia synthesis under room temperature and atmospheric pressure. Here, we demonstrate a simple and rapid approach to synthesize NH3 in the N2+H2+H2O system and illustrate the reaction mechanism by theoretical calculations. The NH3 generation rate can reach 2.847 mg L−1 h−1 with an NH4+ selectivity of 99.45 wt.%. The presence of H2 can inhibit oxidation reactions to form NO3− by‐products and promote proton generation from H2O dissociation. The calculated formation energy of H‐adatom and OH‐adatom from H2O cleavage is −2.86 eV in N2+H2+H2O system, much lower than that in N2+H2O system, verifying much easier dissociation of H2O molecules and significantly facilitated proton generation to enlarge the NH4+ yield. This work provides a simple approach to improve mechanochemical N2 fixation performance and highlights a proton generation enhancement mechanism.
Electrochemical Determination of Flap Endonuclease 1 Activity Amplified by CRISPR/Cas12a Trans‐Cleavage**
Authors: Zhu Yulin , Zhu Jinwen , Gao Yan , Shi Jiayue , Miao Peng
Published: March 2023

Flap endonuclease 1 (FEN1) participates in the DNA replication and repair processes, which plays an important role in maintaining genome stability. Determination of FEN1 level is highly required for biochemical studies and clinical diagnosis. Herein, a novel electrochemical approach for the detection of FEN1 is developed based on clustered regularly interspaced short palindromic repeats (CRISPR) and CRISPR‐associated (Cas) proteins trans‐cleavage. The dumbbell structured DNA substrate, single‐stranded DNA labelled with electrochemical species and three‐dimensional tetrahedral DNA are designed and involved in the reactions. This method displays high sensitivity and good specificity, which can not only monitor FEN1 in various biological samples directly, but also help screen FEN1 inhibitors with potential use for anti‐cancer drug discovery.
Intermetallic Compound TiM (M=Co, Fe) with a Layered Structure Prepared by Deoxidizing Ilmenite‐type Oxides in Molten LiCl‐CaH2 Mixtures
Authors: Kobayashi Yasukazu , Nagaura Tomota , Alowasheeir Azhar , Tada Shohei , Yamauchi Yusuke
Published: March 2023

CsCl‐type intermetallic compounds TiM (M=Co, Fe) were obtained by deoxidizing trigonal ilmenite‐type MTiO3 with a reducing agent CaH2 in molten LiCl at 600 °C. X‐ray diffraction, nitrogen adsorption, scanning electron microscopy, and transmission electron microscopy with energy‐dispersive X‐ray, and X‐ray photoelectron spectroscopy analyses revealed the formation of nanoscale layered structures, which enhanced specific surface areas (approximately 20 m2/g) in the intermetallic compounds. In the initial deoxidation stage, Li2TiO3‐like compounds were observed as an intermediate, suggesting the substitution of M in MTiO3 by Li from the molten LiCl. Compound MTiO3 has a layered structure perpendicular to the c axis of the trigonal structure, suggesting that the layered structures may originate from the crystal structure of the precursors. Formation of the Li2TiO3‐like intermediate may help maintain the original layered structure during deoxidation and the subsequent alloying at temperatures as low as 600 °C.
Structural and Synthetic Insights on Oxidative Homocouplings of Alkynes Mediated by Alkali‐Metal Manganates
Authors: Mastropierro Pasquale , Platten Andrew W. J. , Kennedy Alan R. , Hevia Eva , Uzelac Marina
Published: March 2023

Exploiting bimetallic cooperation alkali‐metal manganate (II) complexes can efficiently promote oxidative homocoupling of terminal alkynes furnishing an array of conjugated 1,3‐diynes. The influence of the alkali‐metal on these C−C bond forming processes has been studied by preparing and structurally characterizing the alkali‐metal tetra(alkyl) manganates [(TMEDA)2Na2Mn(CH2SiMe3)4] and [(PMDETA)2K2Mn(CH2SiMe3)4]. Reactivity studies using phenylacetylene as a model substrate have revealed that for the homocoupling to take place initial metalation of the alkyne is required. In this regard, the lack of basicity of neutral Mn(CH2SiMe3)2 precludes the formation of the diyne. Contrastingly, the tetra(alkyl) alkali‐metal manganates behave as polybasic reagents, being able to easily deprotonate phenylacetylene yielding [{(THF)4Na2Mn(C≡CPh)4}∞] and [(THF)4Li2Mn(C≡CPh)4]. Controlled exposure of [{(THF)4Na2Mn(C≡CPh)4}∞] and [(THF)4Li2Mn(C≡CPh)4] to dry air confirmed their intermediary in formation of 1,4‐diphenyl‐1,3‐butadiyne in excellent yields. While the Na/Mn(II) partnership proved to be the most efficient in stoichiometric transformations, under catalytic regimes, the combination of MC≡CAr (M= Li, Na) and MnCl2 (6 mol %) only works for lithium, most likely due to the degradation of alkynylsodiums under the aerobic reaction conditions.
Teicoplanin aglycone media and carboxypeptidase Y: Tools for finding low‐abundance D‐amino acids and epimeric peptides
Authors: Sung Yu‐Sheng , Khvalbota Liudmyla , Dhaubhadel Umang , Špánik Ivan , Armstrong Daniel W.
Published: March 2023

D‐amino acids and epimeric peptides/proteins can play crucial biological roles and adversely affect protein folding and oligopeptide aggregation in age‐related pathologies in humans. This has ignited interest in free D‐amino acids as well as those incorporated in peptides/proteins and their effects in humans. However, such stereoisomeric analytes are often elusive and in low abundance with few existing methodologies capable of scouting for and identifying them. In this work, we examine the feasibility of using teicoplanin aglycone, a macrocyclic antibiotic, which has been reported to strongly retain D‐amino acids and peptides with a D‐amino acid on the C‐terminus, for use as a solid phase extraction (SPE) medium. The HPLC retention factors of L‐/D‐amino acids and C‐terminus modified D‐amino acid‐containing peptides and their L‐amino acid exclusive counterparts on teicoplanin aglycone are presented. Retention curve differences between amino acids and peptides highlight regions of solvent composition that can be utilized for their separation. This approach is particularly useful when coupled with enzymatic hydrolysis via carboxypeptidase Y to eliminate all L‐amino acid exclusive peptides. The remaining peptides with carboxy‐terminal D‐amino acids are then more easily concentrated and identified.
Co‐Digestion of Water Hyacinth and Duck Manure for Potential Low‐Cost Biogas Production by Rural Communities
Authors: Jamaluddin Julaikha , Zulkeflee Zufarzaana
Published: March 2023

Leftover harvested water hyacinth biomass and duck manure can create waste management issues. As they are readily abundant and available, potential co‐digestion of both waste sources for biogas production is explored as a waste‐to‐energy approach for a rural fishermen community. Seven 19‐L do‐it‐yourself bioreactors are constructed with four different feedstock mixing ratios. The mixing ratios of water hyacinth to duck manure are varied at 70:30, 50:50, and 30:70, and are conducted in duplicate. One reactor utilizing 100% water hyacinth as feedstock acts as the control. Biogas production is measured daily for 50 days through the water displacement method. Variations in pH and chemical oxygen demand levels are monitored weekly. The results show that the highest biogas production is from the mixture of water hyacinth to duck manure at a 70:30 ratio (p < 0.05), with a volume of cumulative gas produced at 4.27 L that can be well simulated through the logistic function kinetic model (R2 = 0.965). The biogas produced consists of methane, carbon monoxide, and hydrogen sulfide. The findings prove the potential of water hyacinth and duck manure as feedstocks for biogas production as one of the waste management solutions that can be practiced by the community.
Clinical implications of tumor‐based next‐generation sequencing in high‐grade epithelial ovarian cancer
Authors: Foster Katherine I. , Shaw Kenna R. M. , Jin Jeff , Westin Shannon N. , Yap Timothy A. , Glassman Deanna M. , Jazaeri Amir A. , Rauh‐Hain Jose A. , Lee Sanghoon , Fellman Bryan M. , Ju Zhenlin , Liu Yuexin , Fleming Nicole D. , Sood Anil K.
Published: March 2023

Background

Tumor‐based next‐generation sequencing is used inconsistently as a tool to tailor treatment of ovarian cancer, yet beyond detection of somatic BRCA1 and BRCA2 mutations, the clinical benefit is not well established. This study aimed to assess the clinical relevance of tumor‐based next‐generation sequencing (tbNGS) in patients with ovarian cancer.

Methods

This retrospective study included patients with high‐grade epithelial ovarian carcinoma. tbNGS results were identified in the electronic medical record using optical character recognition and natural language processing. Genetic, clinical, and demographic information was collected. Progression‐free survival (PFS) and overall survival were calculated and compared using log‐rank tests. Multivariate Cox regression and clustering analyses were used to identify patterns of genetic alterations associated with survival.

Results

Of 1092 patients in the described population, 409 (37.5%) had tbNGS results. Nearly all (96.1% [393/409]) had one or more genetic alterations. In 25.9% (106/409) of patients, an alteration that aligned with a targeted treatment was identified, and in an additional 48.7% (199/409), tbNGS results suggested eligibility for an investigational agent or clinical trial. The most frequent alterations were TP53, PIK3CA, and NF1 mutations, and CCNE1 amplification. Together, BRCA1 and BRCA2 mutations were associated with longer PFS (hazard ratio [HR], 0.62; 95% confidence interval [CI], 0.42–0.92; p = .02), whereas AKT2 amplification was associated with shorter PFS (HR, 3.86; 95% CI, 1.002–14.88; p < .05). Multivariate Cox regression and clustering analyses identified several combinations of genetic alterations that corresponded to outcomes in patients with high‐grade serous carcinoma.

Conclusions

tbNGS often yields clinically relevant information. Detailed analysis of population‐level tumor genomics may help to identify therapeutic targets and guide development of clinical decision support tools.

Plain Language Summary

Although more and more patients with ovarian cancer are undergoing tumor‐based next‐generation sequencing to identify genetic mutations in their tumors, the benefits of such testing are not well established.

In a group of over 400 patients with ovarian cancer who underwent tumor‐based next‐generation sequencing in the course of their treatment, nearly all patients had one or more genetic alterations detected, and one out of four patients had a mutation that qualified them for a personalized treatment option.