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A HfO2 film was grown using discrete feeding ALD, an advanced ALD process designed to improve the surface coverage of the precursor, which decreased the residual impurities in the film and increased the film density.

The present world continues to face unprecedented challenges caused by the COVID-19 pandemic. Collaboration between researchers of multiple disciplines is the need of the hour. There is a need to develop antiviral agents capable of inhibiting viruses and tailoring existing antiviral drugs for efficient delivery to prevent a surge in deaths caused by viruses globally. Biocompatible systems have been designed using nanotechnological principles which showed appreciable results against a wide range of viruses. Many nanoparticles can act as antiviral therapeutic agents if synthesized by the correct approach. Moreover, nanoparticles can act as carriers of antiviral drugs while overcoming their inherent drawbacks such as low solubility, poor bioavailability, uncontrolled release, and side effects. This review highlights the potential of nanomaterials in antiviral applications by discussing various studies and their results regarding antiviral potential of nanoparticles while also suggesting future directions to researchers.

Electric-potential-assisted atomic layer deposition was demonstrated for Ru film growth. Surface reaction was modified via the electric potential, which affected the nucleation and microstructure of films. Assorted film properties were improved notably.

The specialized cell-types of the mucociliary epithelium (MCE) lining the respiratory tract enable continuous airway clearing, with its defects leading to chronic respiratory diseases. The molecular mechanisms driving cell-fate acquisition and temporal specialization during mucociliary epithelial development remain largely unknown. Here, we profile the developingXenopusMCE from pluripotent to mature stages by single-cell transcriptomics, identifying novel, multipotentearly epithelial progenitorsthat execute multi-lineage cues before specialising into late-stage ionocytes, goblet and basal cells. Combiningin silicolineage inference,in situhybridization and single-cell multiplexed RNA imaging, we capture the initial bifurcation into early epithelial and multiciliated progenitors, chart cell- type emergence and fate progression into specialized cell-types. Comparative analysis of nine airway atlases reveals an evolutionary conserved transcriptional module in ciliated cells, whereas secretory and basal types execute distinct function-specific programmes across vertebrates. We uncover a continuous non-hierarchical model of MCE development alongside a significant data resource for understanding respiratory biology.

Successive ionic layer adsorption and reaction (SILAR) process has been diversely used for deposition of various metal chalcogenides. SnS is one of them. Owing to the under-utilization of ionic precursor used in SILAR process, recovery of ionic species from solvents is important and critical before disposal. Since a variety of solutes and solvents can be used for the deposition of SnS, we have devised a comparison revealing the diversity of SnS. It is revealed that the residual cationic precursors play an important role in deciding the eventual morphology, purity and thus the photocatalytic performance of nanostructured SnS. We directly compared SnS nanostructures salvaged from ionic precursors of SnSO4 and SnCl2 under similar salvaging conditions and ensued that flower-like SnS can be obtained successfully. Intensive scanning electron microscopy and energy dispersive spectroscopy were utilized to have a closer check on the evolution of morphological and compositional characteristics. Rhodamine B and methylene blue dyes were successfully degraded by both types SnS, however SnS@SnCl2 exhibited superior performance which was credited to its unique flower-like morphology. Significantly, ~ 96.3% removal of methylene blue dye from water was achieved in only 40 min.

In recent years, resistive switching memory devices are attracted much attention for high-density non-volatile memory applications owing to their cell scalability, multilevel operations, and 3D capability in crossbar memory arrays. In this work, we report the forming-free and multilevel resistive switching properties of hydrothermally synthesized hexagonal molybdenum oxide (h-MoO3) microrods. The formation of h-MoO3 microrods was confirmed by using the X-ray diffraction technique and scanning electron microscopy. Different chemical properties of h-MoO3 microrods were determined by energy-dispersive X-ray, photoluminescence, Raman, and X-ray photoelectron spectroscopic techniques. The memory device was fabricated in a Ti/MoO3/FTO structure and its bipolar resistive switching properties were investigated. The memory device shows voltage-dependent tunable I-V properties and shows electroforming-free operation. Moreover, we have calculated the different memristive properties and showed that the device possesses double-valued charge-magnetic flux characteristics, suggesting the dominance of memristive properties in the Ti/MoO3/FTO device. We further explored the multilevel resistive switching property of the device by varying the RESET voltage. The Ti/MoO3/FTO memristive device can able to show four distinct resistive states during endurance and retention tests. The statistical analysis suggested that the device has less variation during the cycle-to-cycle operation. The device conduction mechanism was obtained by fitting different charge transport models, and a possible resistive switching mechanism is presented based on the observed multilevel resistive switching effect of the Ti/MoO3/FTO memristive device.

Nanoporous SnO2@TiO2 heterostructure was synthesized by a facile two-step dry process, modified thermal evaporation followed by atomic layer deposition (ALD). The introduction of inert gas, Ar, with a pressure of 0.2 Torr during thermal evaporation of SnO, enabled the formation of the nanoporous 3D structure by inducing the collision and loss of kinetic energy during deposition. A photocatalytic material, TiO2, was grown on the porous structure of SnO2 to detect target gas, formaldehyde, under UV irradiation selectively. Microstructural and elemental analysis with a transmission electron microscope and X-ray photoelectron spectroscopy confirmed the porous structure of SnO2 induced by our evaporation process as well as the conformal coating of TiO2 on the porous structure. The sensing capabilities of a photoactive sensor on the formaldehyde were assessed in terms of the film porosity, irradiated UV power, and thickness of photoactive materials at room temperature. As a result, the SnO2@TiO2 heterostructure, with an optimum thickness of TiO2 exhibited low detection limit, down to 0.1 ppm, good linearity to the concentration of formaldehyde in the range of 0.1???10 ppm, and high response of 15% in the HCHO 0.1 ppm. This core-shell porous structure developed by modified thermal evaporation combined with ALD paved the way for 3D architectures to explore various applications, such as biosensors, photocatalysts, and optoelectronic devices.

The electronic structure of an atomic-layer-deposited MoS2 monolayer on SiO2 was investigated using X-ray absorption spectroscopy (XAS) and synchrotron X-ray photoelectron spectroscopy (XPS). The angle-dependent evolution of the XAS spectra and the photon-energy-dependent evolution of the XPS spectra were analyzed in detail using an ab-initio electronic structure simulation. Although similar to the theoretical spectra of an ideal free-standing MoS2 ML, the experimental spectra exhibit features that are distinct from those of an ideal ML, which can be interpreted as a consequence of S-O van der Waals (vdW) interactions. The strong consensus among the experimental and theoretical spectra suggests that the vdW interactions between MoS2 and adjacent SiO2 layers can influence the electronic structure of the system, manifesting a substantial electronic interaction at the MoS2-SiO2 interface.

A two-dimensional electron gas (2DEG) was formed at the interface of an ultrathin Al2O3/TiO2 heterostructure that was fabricated using atomic layer deposition (ALD) at a low temperature (

Metal and transition-metal dichalcogenide (TMD) hybrid systems have been attracting growing research attention because exciton-plasmon coupling is a desirable means of tuning the physical properties of TMD materials. Competing effects of metal nanostructures, such as the local electromagnetic field enhancement and luminescence quenching, affect the photoluminescence (PL) characteristics of metal/TMD nanostructures. In this study, we prepared TMD MoS2 monolayers on hexagonal arrays of Au nanodots and investigated their physical properties by micro-PL and surface photovoltage (SPV) measurements. MoS2 monolayers on bare Au nanodots exhibited higher PL intensities than those of MoS2 monolayers on 5-nm-thick Al2O3-coated Au nanodots. The Al2O3 spacer layer blocked charge transfer at the Au/MoS2 interface but allowed the transfer of mechanical strain to the MoS2 monolayers on the nanodots. The SPV mapping results revealed not only the electron-transfer behavior at the Au/MoS2 contacts but also the lateral drift of charge carriers at the MoS2 surface under light illumination, which corresponds to nonradiative relaxation processes of the photogenerated excitons.

One of the efficient strategies to enhance light harvesting capability of metal oxides nanoparticles (NPs) is to deposit low band gap metal sulfides on them via pseudo-successive ionic layer adsorption and reaction (p-SILAR). Resultant oxide-sulfide nanocomposites have a variety of applications, however there is still a need to increase the deposition of metal sulfide in the form of quantum-dots (QDs). In this work, we have successfully enhanced the deposition of QDs on TiO2 NPs using a modernized H2S-treatment strategy. A rotary reactor was employed for H2S-treatment of TiO2 NPs, ensuing higher deposition of PbS (in TiO2–PbS) and CdS (in TiO2–CdS) via p-SILAR. Resultantly, dye degradation of Rhodamine B increased from 63% to 75% and 72%–84%, respectively. X-ray photoelectron spectroscopy revealed the efficacy of modernized H2S-treatment while intensive electrochemical characterization affirmed reduction in charge carrier transfer resistances due to superior deposition of PbS and CdS QDs on TiO2 NPs.

An ideal cancer therapeutic strategy involves the selective killing of cancer cells without affecting the surrounding normal cells. However, researchers have failed to develop such methods for achieving selective cancer cell death because of shared features between cancerous and normal cells. In this study, we have developed a therapeutic strategy called the cancer-specific insertions-deletions (InDels) attacker (CINDELA) to selectively induce cancer cell death using the CRISPR-Cas system. CINDELA utilizes a previously unexplored idea of introducing CRISPR-mediated DNA double-strand breaks (DSBs) in a cancer-specific fashion to facilitate specific cell death. In particular, CINDELA targets multiple InDels with CRISPR-Cas9 to produce many DNA DSBs that result in cancer-specific cell death. As a proof of concept, we demonstrate here that CINDELA selectively kills human cancer cell lines, xenograft human tumors in mice, patient-derived glioblastoma, and lung patient-driven xenograft tumors without affecting healthy human cells or altering mouse growth.

Chondrocytes secrete massive extracellular matrix (ECM) molecules that are produced, folded, and modified in the endoplasmic reticulum (ER). Thus, the ER-associated degradation (ERAD) complex—which removes misfolded and unfolded proteins to maintain proteostasis in the ER— plays an indispensable role in building and maintaining cartilage. Here, we examined the necessity of the ERAD complex in chondrocytes for cartilage formation and maintenance. We show that ERAD gene expression is exponentially increased during chondrogenesis, and disruption of ERAD function causes severe chondrodysplasia in developing embryos and loss of adult articular cartilage. ERAD complex malfunction also causes abnormal accumulation of cartilage ECM molecules and subsequent chondrodysplasia. ERAD gene expression is decreased in damaged cartilage from patients with osteoarthritis (OA), and disruption of ERAD function in articular cartilage leads to cartilage destruction in a mouse OA model., Description, Reduced secretory activity due to the unfolded protein accumulation in chondrocytes may worsen cartilage damage and loss in osteoa.

Electrocatalyst/insulator/semiconductor configurations have been considered as promising designs for efficient photoelectrochemical (PEC) water-splitting reactions. However, the roles and effects o...

Lactate sensors are increasingly used for applications in sports and clinical medicine, but currently have several shortcomings including low sensitivity. We demonstrate a highly sensitive and selective non-enzymatic lactate sensor based on porous nickel oxide by sol-gel based inverse micelle method. The porosity and surface area of nickel oxide depending on the calcination temperature (250, 350, and 450 °C) were compared using electron microscopy and a Brunauer-Emmett-Teller (BET) surface area analyzer. Furthermore, we also compared the chemical state of Ni3+ in porous nickel oxides, which is known to be strongly engaged with electrocatalytic lactate detection, with different calcination temperature. The sensing characteristics were assessed using an amperometric response with a three-electrode system. Owing to a relatively large surface area and high Ni3+/Ni2+ ratio, NiO calcined at 250 °C, exhibit maximum sensitivity at 62.35 μA/mM (cm2), and a minimum detection of limit of 27 μM, although, it has large amount of organic residue because of low calcination temperature. In addition to its sensitivity, a porous nickel oxide electrode also displays good selectivity against other interferents such as l -ascorbic acid, uric acid, and dopamine, further supporting its potential as a non-enzymatic lactate sensor.

Background Cell migration is a basic cellular behavior involved in multiple phenomena in the human body such as embryonic development, wound healing, immune reactions, and cancer metastasis. For proper cell migration, integrin and the ECM binding complex must be disassembled for the retraction of trailing edges. Objective Integrin must be differentially regulated at leading edges or trailing edges during cell migration. Previously, we showed that ITGBL1 was a secreted protein and inhibits integrin activity. Therefore, we examined the function of ITGBL1 on the retraction of trailing edges during cell migration. Methods To examined the function of ITGBL1 on cell migration, we knocked-down or overexpressed ITGBL1 by using ITGBL1 siRNA or ITGBL1 plasmid DNA in human chondrocytes or ATDC5 cells. We then characterized cellular migration and directionality by performing wound healing assays. Also, to analyze leading-edge formation and trailing-edge retraction, we labeled cell membranes with membrane-GFP and performed live imaging of migrating cells and. Finally, we specifically detected active forms of integrin, FAK and Vinculin using specific antibodies upon ITGBL1 depletion or overexpression. Result In this study, ITGBL1 preferentially inhibited integrin activity at the trailing edges to promote cell migration. ITGBL1-depleted cells showed increased focal adhesions at the membranous traces of trailing edges to prevent the retraction of trailing edges. In contrast, overexpression of ITGBL1 upregulated directional cell migration by promoting focal adhesion disassembly at the trailing edges. Conclusion ITGBL1 facilitates directional cell migration by promoting disassembly of the trailing edge focal adhesion complex.

Glutathione peroxidase 1 (Gpx1) and peroxiredoxin 2 (Prdx2) belong to the thiol peroxidase family of antioxidants, and have been studied for their antioxidant functions and roles in cancers. However, the physiological significance of Gpx1 and Prdx2 during vertebrate embryogenesis are lacking. Currently, we investigated the functional roles of Gpx1 and Prdx2 during vertebrate embryogenesis using Xenopus laevis as a vertebrate model. Our investigations revealed the zygotic nature of gpx1 having its localization in the eye region of developing embryos, whereas prdx2 exhibited a maternal nature and were localized in embryonic ventral blood islands. Furthermore, the gpx1-morphants exhibited malformed eyes with incompletely detached lenses. However, the depletion of prdx2 has not established its involvement with embryogenesis. A molecular analysis of gpx1-depleted embryos revealed the perturbed expression of a cryba1-lens-specific marker and also exhibited reactive oxygen species (ROS) accumulation in the eye regions of gpx1-morphants. Additionally, transcriptomics analysis of gpx1-knockout embryos demonstrated the involvement of Wnt, cadherin, and integrin signaling pathways in the development of malformed eyes. Conclusively, our findings indicate the association of gpx1 with a complex network of embryonic developmental pathways and ROS responses, but detailed investigation is a prerequisite in order to pinpoint the mechanistic details of these interactions.

We examined the chemical and local structural properties of oxidized TiN/ZnS and TiN/ZnO thin films using X-ray absorption spectroscopy (XAS). The composite films were oxidized by post-deposition annealing (PDA) under various oxygen partial pressures (P(O2)). The results of the X-ray absorption near-edge structure (XANES) analyses showed that the S and N vaporized, and a zinc titanate (ZnTiO3)-like phase formed when annealed under the oxygen ambiance. An ab initio XANES simulation as well as the extended X-ray absorption fine structure (EXAFS) analysis further resolved the local structures of ZnTiO3-like phase into high symmetry structures such as ilmenite-like or perovskite-like local structure; for instance, the local structure of TiN/ZnS films annealed with P(O2) = 2 Torr could be described as a mixture of 50% ilmenite ZnTiO3 + 30% perovskite ZnTiO3 + 20% wurtzite ZnO local structures. The formation of ZnTiO3-like local structure is also subject to the temperature during the PDA or the choice of bottom layers (ZnS or ZnO). The temperature of the TiN/ZnS-to-ZnTiO3 local structural phase transformation, was estimated to be 500–600 °C at P(O2) = 2 Torr, and ZnO as bottom layer apparently expedited such local structural evolution by supplying oxygen to TiN.

S passivation of a HfO2 film on an InP substrate is demonstrated using annealing in H2S ambient either before or after ALD of the HfO2 film. We examined the resulting distribution and chemical state of the incorporated S both in the HfO2 film and at its interface with the InP substrate using secondary ion mass spectroscopy and X-ray absorption spectroscopy. Annealing in H2S ambient before ALD of HfO2 resulted in accumulation of S at the interface in the sulfide (S2−) phase (due to lack of oxygen), which effectively suppressed interfacial reactions during ALD and passivated interfacial defect states. On the other hand, annealing in H2S ambient after ALD of the HfO2 film induced a sulfate (S6+) phase in the film due to the abundant oxygen in the film, as well as a sulfide (S2−) phase at the interface. This improved the charge trapping behavior by decreasing the bulk defect density in the HfO2 film.

A g-C3N4@ZnO heterojunction is demonstrated using atomic layer deposition (ALD) of ZnO. A specially designed rotary reactor was used to maintain mechanical dispersion of g-C3N4 powder during the ALD process. Stable, uniform, and intimate heterojunctions between g-C3N4 and ZnO were produced, which induced effective charge separation; thus, the photocatalytic activity of the composites was enhanced. The photocatalytic performance was evaluated by the degradation of methylene blue dye. The photocatalytic reaction rate constant of the optimal g-C3N4@ZnO with five ALD cycles was five times and two times higher than those of pristine g-C3N4 and g-C3N4@TiO2 composite, respectively. Furthermore, the photocorrosion of ZnO was inhibited by coupling with g-C3N4, which was confirmed through cyclic photo-degradation with three consecutive dye degradation tests. The synergistic effects of the g-C3N4@ZnO heterojunction, enhanced photocatalytic activity and photocorrosion resistance were proven.

SiO2 is one of the most important dielectric materials that is widely used in the microelectronics industry, but its growth or deposition requires high thermal budgets. Herein, we report a low-temp...

Size and shape of inorganic materials are known to have great effects on their physical and chemical properties. Here, for the first time we report the visible light driven photocatalytic degradation of erioglaucine – a stable organic dye molecule in the presence of chemically synthesized nanoscale CdS with 1D (nanorods), 2D (nanosheets) and 3D (hierarchical) morphology. Visible light driven photocatalytic degradation efficiency of both 1D and 3D CdS in the removal of erioglaucine are identical. Surprisingly, with 5 min of sonication, the highly crystalline 3D CdS stacked with many thin nanowires containing numerous active surface sites exhibited four-fold enhanced photodegradation efficiency in comparison to 1D and 2D CdS. Scavenger studies revealed that electrons and superoxide radicals are primary reactive species involved in the photodegradation of erioglaucine, while cyclic photodegradation studies revealed the good stability of 3D CdS against photocorrosion. Further, the photocatalytic hydrogen evolution studies also revealed the excellent activity of 3D CdS in comparison to 1D and 2D CdS. Thus, we find that the morphology indeed influences the photocatalytic activity. These results reveal that 3D CdS nanostructures investigated in the present work are efficient photocatalysts that could be fine-tuned for both environmental remediation and hydrogen generation applications.

We demonstrated surface passivation of a black Si-based solar cell using an (NH4)2S solution to mitigate surface recombination velocity. Incorporated S at the interface between atomic-layer-deposited Al2O3 and black Si by (NH4)2S solution treatment boosted the density of negative fixed charges, S-enhanced field-effect passivation. Furthermore, NH4OH generated during (NH4)2S solution treatment removed the defective Si phase at the black Si surface, the surface cleaning effect. The optimized (NH4)2S solution treatment significantly enhanced the internal quantum efficiency up to ∼17.2% in the short wavelength region, suggesting suppressed surface recombination. As a result, photoconversion efficiency of the cell increased from 11.6 to 13.5%, by 16% compared to the control cells without (NH4)2S solution treatment.