Surfactant-Free, Size-Controllable, and Scalable Green Synthesis of ZIF-8 Particles with Narrow Size Distribution by Tuning Key Reaction Parameters in Water Solvent.

The chemical/physical properties and reliable performance of nanoporous materials are strongly influenced by the particle size and corresponding distribution. Among many types of MOFs, ZIF-8, is still widely used and many studies have been conducted to control the particle size and uniformity of ZIF-8 using surfactants and organic solvents. However, the use of surfactants and organic solvents process is expensive and may cause environmental pollution. For the first time, in this paper, a surfactant-free, size-controllable, and scalable green synthesis method of ZIF-8 particles is reported using four reaction parameters (temperature, concentration, pouring time, and reactant ratio) that affect the formation of nuclei and growth of ZIF-8 crystals. The as-synthesized ZIF-8 nanoparticles show great uniformity and controllable particle sizes in the wide range of 147-915 nm. In addition, a 2 L large-scale synthesis of ZIF-8 with narrow size distribution is developed by finely tuned particle size in water without any additives. To demonstrate the efficient utilization of nanopores according to the particle size and size distribution, an adsorption test is conducted on the ZIF-8 nanoparticles. This study will support the synthesis of size-controlled ZIF-8 with narrow size distribution and their composites for achieving high performance in the emerging applications.

Extending the Range of Distances Accessible by 19F Electron-Nuclear Double Resonance in Proteins Using High-Spin Gd(III) Labels.

Fluorine electron-nuclear double resonance (19F ENDOR) has recently emerged as a valuable tool in structural biology for distance determination between F atoms and a paramagnetic center, either intrinsic or conjugated to a biomolecule via spin labeling. Such measurements allow access to distances too short to be measured by double electron-electron resonance (DEER). To further extend the accessible distance range, we exploit the high-spin properties of Gd(III) and focus on transitions other than the central transition (|-1/2⟩ ↔ |+1/2⟩), that become more populated at high magnetic fields and low temperatures. This increases the spectral resolution up to ca. 7 times, thus raising the long-distance limit of 19F ENDOR almost 2-fold. We first demonstrate this on a model fluorine-containing Gd(III) complex with a well-resolved 19F spectrum in conventional central transition measurements and show quantitative agreement between the experimental spectra and theoretical predictions. We then validate our approach on two proteins labeled with 19F and Gd(III), in which the Gd-F distance is too long to produce a well-resolved 19F ENDOR doublet when measured at the central transition. By focusing on the |-5/2⟩ ↔ |-3/2⟩ and |-7/2⟩ ↔ |-5/2⟩ EPR transitions, a resolution enhancement of 4.5- and 7-fold was obtained, respectively. We also present data analysis strategies to handle contributions of different electron spin manifolds to the ENDOR spectrum. Our new extended 19F ENDOR approach may be applicable to Gd-F distances as large as 20 Å, widening the current ENDOR distance window.

CFAP61 knockdown aggravates male infertility by inhibiting testosterone secretion by Leydig cells via the MAPK/COX-2 pathway.

This study aimed to elucidate the roles of cilia- and flagella-associated protein 61 (CFAP61) in male infertility and its underlying mechanisms. CFAP61 expression levels in the testicular tissues of male patients with infertility were determined using quantitative real-time polymerase chain reaction, immunohistochemical assay, and western blotting. Moreover, the specific roles of CFAP61 in male infertility were evaluated using cell counting kit-8, 5-ethynyl-2'-deoxyuridine, flow cytometry, and enzyme-linked immunosorbent assays. Here, CFAP61 was expressed at low levels in the testicular tissues of male patients with infertility. Functionally, CFAP61 knockdown reduced the Leydig cell viability and testosterone secretion and enhanced apoptosis. A mechanistic study further revealed that silencing CFAP61 promoted the expression levels of mitogen-activated protein kinase (MAPK)/cyclooxygenase-2 (COX-2) signaling pathway-related proteins (p-extracellular signal-regulated kinase (p-ERK), p-c-Jun N-terminal kinase (p-JNK), p-P38, and COX-2). In conclusion, CFAP61 knockdown facilitated male infertility by suppressing Leydig cell viability and testosterone secretion and enhanced cell apoptosis by activating the MAPK/COX-2 pathway. Our data suggest CFAP61 as a potential therapeutic target for male infertility.

Room-Temperature van der Waals Ferromagnet Switching by Spin-Orbit Torques.

The emerging wide varieties of the van der Waals (vdW) magnets with atomically thin and smooth interfaces hold great promise for next-generation spintronic devices. However, due to the lower Curie temperature of the vdW ferromagnets than room temperature, electrically manipulating its magnetization at room temperature has not been realized. In this work, it is demonstrated that the perpendicular magnetization of the vdW ferromagnet Fe3 GaTe2 can be effectively switched at room temperature in the Fe3 GaTe2 /Pt bilayer by spin-orbit torques (SOTs) with a relatively low current density of 1.3 × 107 A cm-2 . Moreover, the high SOT efficiency of ξDL ≈ 0.28 is quantitatively determined by harmonic measurements, which is higher than those in Pt-based heavy metal/conventional ferromagnet devices. The findings of room-temperature vdW ferromagnet switching by SOTs provide a significant basis for the development of vdW-ferromagnet-based spintronic applications.

Redesigning Natural Materials for Energy, Water, Environment, and Devices.

The United Nations Framework Convention on Climate Change (UNFCCC) acknowledges that global cooperation is paramount to mitigate climate change and further warming. The global community is committed to renewable energy and natural materials to tackle this challenge for all humankind. The widespread use of natural materials is embraced as one such action to reach net-zero carbon emissions. Given the hierarchical framework and earth abundance, cellulose-based materials extend their negative carbon benefits to our daily products and accelerate our pace toward carbon neutrality. Here, we present an overview of recent developments of cellulose-based materials in upsurging applications in radiative cooling, thermal insulation, nanofluidics, and wearable devices. We also highlight various modifications and functionalized processes that transform massive amounts of cellulose into green products. The prosperous development of functionalized cellulose materials aligns with a circular economy. Expedited interdisciplinary fundamental investigations are expected to make fibrillated cellulose penetrate more into carbon downdraw at speed and scale.

Large and tunable magnetoresistance in van der Waals ferromagnet/semiconductor junctions.

Magnetic tunnel junctions (MTJs) with conventional bulk ferromagnets separated by a nonmagnetic insulating layer are key building blocks in spintronics for magnetic sensors and memory. A radically different approach of using atomically-thin van der Waals (vdW) materials in MTJs is expected to boost their figure of merit, the tunneling magnetoresistance (TMR), while relaxing the lattice-matching requirements from the epitaxial growth and supporting high-quality integration of dissimilar materials with atomically-sharp interfaces. We report TMR up to 192% at 10 K in all-vdW Fe3GeTe2/GaSe/Fe3GeTe2 MTJs. Remarkably, instead of the usual insulating spacer, this large TMR is realized with a vdW semiconductor GaSe. Integration of semiconductors into the MTJs offers energy-band-tunability, bias dependence, magnetic proximity effects, and spin-dependent optical-selection rules. We demonstrate that not only the magnitude of the TMR is tuned by the semiconductor thickness but also the TMR sign can be reversed by varying the bias voltages, enabling modulation of highly spin-polarized carriers in vdW semiconductors.

Synthesis, Characterization, Properties, and Biomedical Application of Chitosan-Based Hydrogels.

The prospective applications of chitosan-based hydrogels (CBHs), a category of biocompatible and biodegradable materials, in biomedical disciplines such as tissue engineering, wound healing, drug delivery, and biosensing have garnered great interest. The synthesis and characterization processes used to create CBHs play a significant role in determining their characteristics and effectiveness. The qualities of CBHs might be greatly influenced by tailoring the manufacturing method to get certain traits, including porosity, swelling, mechanical strength, and bioactivity. Additionally, characterization methods aid in gaining access to the microstructures and properties of CBHs. Herein, this review provides a comprehensive assessment of the state-of-the-art with a focus on the affiliation between particular properties and domains in biomedicine. Moreover, this review highlights the beneficial properties and wide application of stimuli-responsive CBHs. The main obstacles and prospects for the future of CBH development for biomedical applications are also covered in this review.

Bioinspired Super Thermal Insulating, Strong and Low Carbon Cement Aerogel for Building Envelope.

The energy crisis has arisen as the most pressing concern and top priority for policymakers, with buildings accounting for over 40% of global energy consumption. Currently, single-function envelopes cannot satisfy energy efficiency for next-generation buildings. Designing buildings with high mechanical robustness, thermal insulation properties, and more functionalities has attracted worldwide attention. Further optimization based on bioinspired design and material efficiency improvement has been adopted as effective approaches to achieve satisfactory performance. Herein, inspired by the strong and porous cuttlefish bone, a cement aerogel through self-assembly of calcium aluminum silicate hydrate nanoparticles (C-A-S-H, a major component in cement) in a polymeric solution as a building envelop is developed. The as-synthesized cement aerogel demonstrates ultrahigh mechanical performance in terms of stiffness (315.65 MPa) and toughness (14.68 MJ m-3 ). Specifically, the highly porous microstructure with multiscale pores inside the cement aerogel greatly inhibits heat transfer, therefore achieving ultralow thermal conductivity (0.025 W m-1 K-1 ). Additionally, the inorganic C-A-S-H nanoparticles in cement aerogel form a barrier against fire for good fire retardancy (limit oxygen index, LOI ≈ 46.26%, UL94-V0). The versatile cement aerogel featuring high mechanical robustness, remarkable thermal insulation, light weight, and fire retardancy is a promising candidate for practical building applications.

Universal Color Retrofit to Polymer-Based Radiative Cooling Materials.

Polymers with broad infrared emission and negligible solar absorption have been identified as promising radiative cooling materials to offer a sustainable and energy-saving venue. Although practical applications desire color for visual appearance, the current coloration strategies of polymer-based radiative cooling materials are constrained by material, cost, and scalability. Here, we demonstrate a universally applicable coloration strategy for polymer-based radiative cooling materials by nanoimprinting. By modulating light interference with periodic structures on polymer surfaces, specular colors can be induced while maintaining the hemispheric optical responses of radiative cooling polymers. The retrofit strategy is exemplified by four different polymer films with a minimum impact on optical responses compared to the pristine films. Polymer films feature low solar absorption of 1.7-3.7%, and daytime sub-ambient cooling is exemplified in the field test. The durability of radiative cooling and color are further validated by dynamic spectral analysis. Finally, the potential roll-to-roll manufacturing empowers a scalable, low-cost, and easy-retrofitting solution for colored radiative cooling films.

High-Sensitivity and Fast-Speed UV Photodetectors Based on Asymmetric Nanoporous-GaN/Graphene Vertical Junction.

GaN-based photodetectors are strongly desirable in many advanced fields, such as space communication, environmental monitoring, etc. However, the slow photo-response speed in currently reported high-sensitivity GaN-based photodetectors still hinders their applications. Here, we demonstrate a high-sensitivity and fast-speed UV photodetector based on asymmetric Au/nanoporous-GaN/graphene vertical junctions. The nanoporous GaN-based vertical photodetector shows an excellent rectification ratio up to ∼105 at +4 V/-4 V. The photo-responsivity and specific detectivity of the device is up to 1.01 × 104 A/W and 7.84 × 1014 Jones, respectively, more than three orders of magnitude higher than the control planar photodetector. With switching light on and off, the repeatable on/off current ratio of the nanoporous GaN-based vertical photodetector is ∼4.32 × 103, which is about 1.51 × 103 times to that of the control planar device. The measured rise/decay time is 12.2 µs/14.6 µs, which is the fastest value for the high-sensitivity GaN-based photodetectors to date. These results suggest that the asymmetric Au/nanoporous-GaN/graphene structure can improve the sensitivity and the photo-response speed of GaN-based PDs simultaneously.

Melatonin influences the biological characteristics of keloid fibroblasts through the Erk and Smad signalling pathways.

Background: Keloids are abnormal fibrous hyperplasias that are difficult to treat. Melatonin can be used to inhibit the development of certain fibrotic diseases but has never been used to treat keloids. We aimed to discover the effects and mechanisms of melatonin in keloid fibroblasts (KFs). Methods: Flow cytometry, CCK-8 assays, western blotting, wound-healing assays, transwell assays, collagen gel contraction assays and immunofluorescence assays were applied to demonstrate the effects and mechanisms of melatonin in fibroblasts derived from normal skin, hypertrophic scars and keloids. The therapeutic potential of the combination of melatonin and 5-fluorouracil (5-FU) was investigated in KFs. Results: Melatonin significantly promoted cell apoptosis and inhibited cell proliferation, migration and invasion, contractile capability and collagen production in KFs. Further mechanistic studies demonstrated that melatonin could inhibit the cAMP/PKA/Erk and Smad pathways through the membrane receptor MT2 to alter the biological characteristics of KFs. Moreover, the combination of melatonin and 5-FU remarkably promoted cell apoptosis and inhibited cell migration and invasion, contractile capability and collagen production in KFs. Furthermore, 5-FU suppressed the phosphorylation of Akt, mTOR, Smad3 and Erk, and melatonin in combination with 5-FU markedly suppressed the activation of the Akt, Erk and Smad pathways. Conclusions: Collectively, melatonin may inhibit the Erk and Smad pathways through the membrane receptor MT2 to alter the cell functions of KFs, while combination with 5-FU could exert even more inhibitory effects in KFs through simultaneous suppression of multiple signalling pathways.

Enhanced Mechanical Stability and Hydrophobicity of Cellulose Aerogels via Quantitative Doping of Nano-Lignin.

As a porous biomass sustainable material, cellulose aerogel has attracted significant attention due to its unique properties in various applications. However, its mechanical stability and hydrophobicity are huge obstacles hindering practical applications. In this work, nano-lignin quantitative doping cellulose nanofiber aerogel was successfully fabricated via liquid nitrogen freeze drying combing vacuum oven drying. The impact of various parameters (lignin content, temperature, and matrix concentration) on the property of the as-prepared materials was systematically explored, revealing the optimum conditions. The morphology, mechanical properties, internal structure, and thermal degradation of the as-prepared aerogels were characterized by various methods (compression test, contact angle, SEM, BET, DSC, and TGA). Compared with pure cellulose aerogel, the addition of nano-lignin did not significantly change the pore size and specific surface area of the material but could improve its thermal stability. In particular, the enhanced mechanical stable and hydrophobic properties of cellulose aerogel via the quantitative doping of nano-lignin was confirmed. The mechanical compressive strength of 160-13.5 C/L-aerogel is as high as 0.913 MPa, while the contact angle was nearly reaching 90°. Significantly, this study provides a new strategy for constructing a novel cellulose nanofiber aerogel with mechanical stability and hydrophobicity.

GdIII -19 F Distance Measurements for Proteins in Cells by Electron-Nuclear Double Resonance.

Studies of protein structure and dynamics are usually carried out in dilute buffer solutions, conditions that differ significantly from the crowded environment in the cell. The double electron-electron resonance (DEER) technique can track proteins' conformations in the cell by providing distance distributions between two attached spin labels. This technique, however, cannot access distances below 1.8 nm. Here, we show that GdIII -19 F Mims electron-nuclear double resonance (ENDOR) measurements can cover part of this short range. Low temperature solution and in-cell ENDOR measurements, complemented with room temperature solution and in-cell GdIII -19 F PRE (paramagnetic relaxation enhancement) NMR measurements, were performed on fluorinated GB1 and ubiquitin (Ub), spin-labeled with rigid GdIII tags. The proteins were delivered into human cells via electroporation. The solution and in-cell derived GdIII -19 F distances were essentially identical and lie in the 1-1.5 nm range revealing that both, GB1 and Ub, retained their overall structure in the GdIII and 19 F regions in the cell.

The function and mechanisms of action of circular RNAs in Urologic Cancer.

Kidney, bladder, and prostate cancer are the three major tumor types of the urologic system that seriously threaten human health. Circular RNAs (CircRNAs), special non-coding RNAs with a stabile structure and a unique back-splicing loop-forming ability, have received recent scientific attention. CircRNAs are widely distributed within the body, with important biologic functions such as sponges for microRNAs, as RNA binding proteins, and as templates for regulation of transcription and protein translation. The abnormal expression of circRNAs in vivo is significantly associated with the development of urologic tumors. CircRNAs have now emerged as potential biomarkers for the diagnosis and prognosis of urologic tumors, as well as targets for the development of new therapies. Although we have gained a better understanding of circRNA, there are still many questions to be answered. In this review, we summarize the properties of circRNAs and detail their function, focusing on the effects of circRNA on proliferation, metastasis, apoptosis, metabolism, and drug resistance in kidney, bladder, and prostate cancers.

Ligand-Capped Cobalt(II) Multiplies the Value of the Double-Histidine Motif for PCS NMR Studies.

In structural studies by NMR, pseudocontact shifts (PCSs) provide both angular and distance information. For proteins, incorporation of a di-histidine (diHis) motif, coordinated to Co2+, has emerged as an important tool to measure PCS. Here, we show that using different Co(II)-chelating ligands, such as nitrilotriacetic acid (NTA) and iminodiacetic acid (IDA), resolves the isosurface ambiguity of Co2+-diHis and yields orthogonal PCS data sets with different Δχ-tensors for the same diHis-bearing protein. Importantly, such capping ligands effectively eliminate undesired intermolecular interactions, which can be detrimental to PCS studies. Devising and employing ligand-capping strategies afford versatile and powerful means to obtain multiple orthogonal PCS data sets, significantly extending the use of the diHis motif for structural studies by NMR.

Urushiol modified epoxy acrylate as UV spray painting oriental lacquer ink.

As a natural "water-based" polymer composite material, oriental lacquer is often referred to as the "king of coatings" and is used as a coating in the defense industry, chemical industry, petroleum industry, metallurgy and mining industry, textile painting and dyeing industry, pharmaceutical industry, as well as the protection of ancient buildings and cultural relics. However, the development of modern industrialization is greatly hindered by the high viscosity of oriental lacquer, the difficulty of spraying, the long drying cycle, and the seriousness of allergenicity. Herein, based on the principle of oriental lacquer and the characteristics of prepolymer in ink, we developed a new prepolymer for modulating UV oriental lacquer ink and explored the feasibility of using it as a raw material for UV spray painting. In this study, lacquer phenol was extracted from oriental lacquer and modified with epoxy acrylate by a simple mechanical compounding method to obtain lacquer epoxy acrylate. Moreover, the UV spray painting oriental lacquer ink was also prepared by using it as the main film-forming substance. The orthogonal experiment method was used to optimize the best formulation of UV spray painting oriental lacquer ink by using nozzle passability, viscosity and curing time as test indexes. Meanwhile, the film properties of UV spray painting oriental lacquer inks were also evaluated. The test results show that the UV spray painting oriental lacquer ink prepared with urushiol epoxy acrylate has better dispersion, excellent paint film performance, and solves the problem that oriental lacquer cannot be printed. This present work shows that urushiol epoxy acrylate as a new type of prepolymer has broad application prospects in the actual preparation of UV inks.

Selectively Controlled Ferromagnets by Electric Fields in van der Waals Ferromagnetic Heterojunctions.

Charge transfer plays a key role at the interfaces of heterostructures, which can affect electronic structures and ultimately the physical properties of the materials. However, charge transfer is difficult to manipulate externally once the interface is formed. The recently discovered van der Waals ferromagnets with atomically sharp interfaces provided a perfect platform for the electrical control of interfacial charge transfer. Here, we report magnetoresistance experiments revealing electrically tunable charge transfer in Fe3GeTe2/Cr2Ge2Te6/Fe3GeTe2 all-magnetic van der Waals heterostructures, which can be exploited to selectively modify the switching fields of the top or bottom Fe3GeTe2 electrodes. The directional charge transfer from metallic Fe3GeTe2 to semiconducting Cr2Ge2Te6 is revealed by first-principles calculations, which remarkably modifies the magnetic anisotropy energy of Fe3GeTe2, leading to the dramatically suppressed coercivity. The electrically selective control of magnetism demonstrated in this study could stimulate the development of spintronic devices based on van der Waals magnets.

CircHIPK3 promotes neuroinflammation through regulation of the miR-124-3p/STAT3/NLRP3 signaling pathway in Parkinson's disease.

BACKGROUND: Parkinson's disease (PD) is characterized as a neurodegenerative disease; however, the mechanisms regarding its pathogenesis have not been fully explored. OBJECTIVES: To explore the role of circular RNA homeodomain interacting protein kinase 3 (circHIPK3) in the progression of PD. MATERIAL AND METHODS: The circHIPK3 and microRNA-124 (miR-124) expression in human serum and cerebral fluid was detected using real-time quantitative reverse transcription polymerase chain reaction (qRT-PCR) in 92 PD patients and 95 controls. The circHIPK3 was overexpressed and/or silenced in cells to explore its molecular mechanisms and effects on neuroinflammation. The production of intracellular reactive oxygen species (ROS) was assessed using 2',7'-dichlorodihydrofluorescein diacetate (DCFH-DA) staining. Interleukin 6 (IL-6), IL-1ß and tumor necrosis factor alpha (TNF-α) production in BV2 cells after the indicated treatment was measured using enzyme-linked immunosorbent assay (ELISA). The protein expression of microglia markers (cluster of differentiation molecule 11b (CD11b) and ionized calcium-binding adapter molecule 1 (Iba-1)), pyroptosis-related factors, NLR family pyrin domain containing 3 (NLRP3), apoptosis-associated speck-like protein containing C-terminal caspase recruitment domain (ASC), and caspase-1, signal transducer and activator of transcription 3 (STAT3), and phosphorylated STAT3 (p-STAT3) were examined using western blot analysis. Furthermore, the interaction between circHIPK3, miR-124 and STAT3 was predicted with bioinformatics and examined using fluorescence in situ hybridization (FISH), luciferase reporter assays, RNA pull-down, and RNA immunoprecipitation (RIP). RESULTS: The expression of circHIPK3 in human serum and cerebral fluids was significantly higher than in controls, whereas miR-124 expression was drastically reduced. In addition, lipopolysaccharide (LPS)-treated BV2 cells exhibited higher expression of circHIPK3 and lower miR-124 expression. The SH-SY5Y cells exhibited a significantly impaired viability and elevated apoptotic rate, along with an upregulation of circHIPK3 and a downregulation of miR-124 expression after being treated with supernatants collected from LPS-treated BV2 cells. The upregulation of circHIPK3 increased IL-6, IL-1ß and TNF-α secretion in BV2 cells. The protein expressions of microglia markers (CD11b and Iba-1), as well as pyroptosis-related factors, NLRP3, caspase-1, and ASC, were also increased following the expression of circHIPK3. All these effects were reversed by the addition of miR-124. CONCLUSIONS: The circHIPK3 enhances neuroinflammation by sponging miR-124 and regulating the miR-124-mediated STAT3/NALP3 pathway in PD.