Tunable Periodic Nanopillar Array for MAPbI3 Perovskite Photodetectors with Improved Light Absorption.

In the field of optoelectronic applications, the vigorous development of organic-inorganic hybrid perovskite materials, such as methylammonium lead triiodide (MAPbI3), has spurred continuous research on methods to enhance the photodetection performance. Periodic nanoarrays can effectively improve the light absorption of perovskite thin films. However, there are still challenges in fabricating tunable periodic patterned and large-area perovskite nanoarrays. In this study, we present a cost-effective and facile approach utilizing nanosphere lithography and dry etching techniques to create a large-area Si nanopillar array, which is employed for patterning MAPbI3 thin films. The scanning electron microscopy (SEM) and X-ray diffraction (XRD) results reveal that the introduction of nanopillar structures did not have a significant adverse effect on the crystallinity of the MAPbI3 thin film. Light absorption tests and optical simulations indicate that the nanopillar array enhances the light intensity within the perovskite films, leading to photodetectors with a responsivity of 11.2 A/W and a detectivity of 7.3 × 1010 Jones at 450 nm in wavelength. Compared with photodetectors without nanostructures, these photodetectors exhibit better visible light absorption. Finally, we demonstrate the application of these photodetector arrays in a prototype image sensor.

Highly Crystalized MAPbX3 Perovskite Triangular Nanowire Arrays for Optoelectronic Applications.

Here, a facile fabrication approach for the high-quality 1D perovskite triangular nanowire (TNW) array synthesis through space-confined effect is reported. A soft stamp containing 1D triangular linear array pattern is used to confine the MAPbX3 solution and to guide the growth of the nanowires along the prescribed direction with good crystallinity. The further constructed photodetectors based on the obtained MAPbI3 TNWs exhibit superior photoresponse properties with a responsivity of (125.2 ± 2.5) A W-1 and detectivity of (2.8 ± 0.8) × 1013 Jones at the wavelength of 650 nm. This excellent performance is attributed to the highly crystalline TNW with optical anisotropy and a small asymptotic height, which reduces the probability of the photon reflection and promotes the carrier transport. More interestingly, the increased surface area of the triangular device can present superior flexibility after a couple of thousands of bending cycles. Furthermore, by fabricating 7 × 7 photodetector arrays, the potential image sensor application is demonstrated. The perovskite nanowire fabrication approach is scalable and compatible with current semiconductor manufacturing, which indicates their great potential in broad applications.

Research on partition of phosphorus in the Three Gorges Reservoir on the Yangtze River.

Partition of phosphorus (P) plays an essential role in its ecological effect in surface waters. Yet limited river sampling hinders our understanding for it. P partition between suspended sediments (SS) and aqueous phase in the mainstem of the Three Gorges Reservoir (TGR) on the Yangtze River were studied based on data during 2004-2019. The results reveal that the percentage of DP (dissolved phosphorus) in TP (total phosphorus) (i.e, λ (DP/TP)) decreased remarkably with increasing concentrations of SS, and the empirical equation by nonlinear fitting is λ (DP/TP) = (SS/50 + 80)/(SS + 98) (SS: mg/L, Model I). When SS increased from several mg/L to 180 mg/L, λ (DP/TP) decreased sharply from averagely 0.80 to 0.25. In the range of SSï¹¥ ~ 400 mg/L, λ (DP/TP) tended to be relatively steady remaining between 0.05 and 0.20 with an average of 0.12. The partition coefficient (Kp) of P between SS and aqueous phase was found to decrease with rising SS and Ce (aqueous concentration of P, i.e., DP).The empirical equation based on SS is Kp (L/g) = 1000 × (49 × SS + 900)/(SS2 + 4000 × SS) (SS: mg/L, Model II). When SS increased from <3 mg/L to ~50 mg/L, Kp decreased rapidly from averagely 88 to 23 L/g, and when SS exceeded 50 mg/L, the pace of decreasing of Kp slowed down. The equation based on Ce is Kp (L/g) = 45.88-194.44 × Ce (mg/L) (Model III). When Ce increased from 0.025 to 0.25 mg/L, the average Kp decreased from 50 to 7.0 L/g. Compared with the influence of variation in SS and Ce, the influence of temperature change on Kp can be ignored. New models are advantageous over previously reported ones, and they can be used to better predict P partition and determine whether SS is a sink or a source.

Ordered growth of metal oxides in patterned multi-angle microstructures.

Herein, we report a facile method combining top-down patterning transfer and bottom-up nanorod growth for preparing large-area and ordered TiO2 nanorod arrays. Pre-crystallization seeding was patterned with nanostructured morphologies via interfacial tension-driven precursor solution scattering on various types and period templates. This is a widely applicable strategy for capillary force-driven interfacial patterns, which also shows great operability in complex substrate morphologies with multiple-angle mixing. Moreover, the customized patterned lithographic templates containing English words, Arabic numerals, and Chinese characters are used to verify the applicability and controllability of this hybrid method. In general, our work provides a versatile strategy for the low-cost and facile preparation of hydrothermally growable metal oxide (e.g., ZnO and MnO2) nanostructures with potential applications in the fields of microelectronic devices, photoelectric devices, energy storage, and photocatalysis.

Commercial dishes with gelatin-free microstructured inserts for elongated stem cell self-renewal and pluripotency.

Here, we report the scalable fabrication of 2i-functionalized micro-pyramid-array (µPyA/+2i) inserts for use in commercial multi-well plates, as the alternative cultivation platform for maintaining long-term self-renewal and pluripotency of multiple mESCs and mouse induced pluripotent stem cells. Relevant evidence including cell morphology characterization increased alkaline phosphatase activity, high expression of mESC self-renewal markers, decreased levels of differentiation-associated markers, and high proportion of self-renewal marker cells are provided. Further studies demonstrated that µPyA/+2i could cause a higher cell density in mESC colony, and induce gene expression changes. Subsequent studies showed that µPyA/+2i can influence the cytoskeleton and promote cell adhesion through Cldn-7 upregulation. In summary, these µPyA/+2i inserts offer flexible and gelatin-free micro-envriomnets to maintain long-term self-renewal and pluripotency of mESCs. Enabled by the microstructured inserst, the facile stem cell manipulation and transfer among culture dishes will broaden stem cells both in routine and translational applications.

Controlled synthesis of distiller's grains biochar for turbidity removal in Baijiu.

Resource utilization of distiller's grains (DGs) is crucial for realizing sustainable development of Baijiu industry. In the prevent investigation, a low-cost activated biochar (DGABC) suitable for removing turbidity from low-alcohol Baijiu was prepared by the controlled pyrolysis of DGs, followed by steam activation. The as-prepared biochar featured a large specific surface area (320-480 m2/g) and pore volume (0.45-0.47 cm3/g). Importantly, the DGABC possessed remarkable exterior hydrophily and interior lipophilicity, which guaranteed its good dispersion in alcohol-water system as well as an efficient adsorption to the components with long lipophilic chain. As a result, the DGABC could efficiently remove the turbidity in low-alcohol Baijiu, which was mainly derived from the long lipophilic chain components, such as ethyl palmitate. Meanwhile, most of the flavor esters that had a shorter lipophilic chain and lower hydrophobicity were well kept in the low-alcohol Baijiu. Therefore, this work provided a promising strategy for DGs recycling in Baijiu industry.

Space-Confined seeding and growth of ordered arrays of TiO2 hierarchical nanostructures.

Here, we report a facile approach to fabricate large area ordered arrays of TiO2 hierarchical nanostructures through space-confined seeding and growth on inverted pyramid templates. The mechanisms of space-confined seeding and growth have been systematically explored and studied. The drying TiO2 seed precursor solution prefers to accumulate on the narrow structures including the centre and edges of the inverted pyramid structures, which facilitates to reduce the free energy of the precursor solution surface and form crystal seeds. Followed by hydrothermal treatment, selective growth of TiO2 hierarchical nanostructures on desirable locations, such as only on the centre, only on the edges, or on the entire surface of the inverted pyramid templates, can be achieved. In addition, the growth temperature, duration and solvents affect the morphology of TiO2 hierarchical nanostructures. This work may provide a universal approach to obtain ordered arrays of metal oxide (e.g. ZnO and MnO2, etc.) nanostructures for applications in optics, electrics, energy, and catalysis.

A meta-analysis examined the effect of intrawound vancomycin on surgical site wound infections in non-spinal neurosurgical operation.

To assess the impact of intrawound vancomycin on surgical site wound infections in non-spinal neurosurgical operations, we conducted a meta-analysis. A thorough review of the literature up to September 2022 showed that 4286 participants had a non-spinal neurosurgical operation at the start of the investigations; 1975 of them used intrawound vancomycin, while 2311 were control. Using dichotomous or contentious methods and a random or fixed-effect model, odds ratios (OR) and mean difference (MD) with 95% confidence intervals (CIs) were estimated to evaluate the impact of intrawound vancomycin on surgical site wound infections in non-spinal neurosurgical operation. The intrawound vancomycin had significantly lower surgical site wound infections (OR, 0.28; 95% CI, 0.19-0.40; P < .001) with low heterogeneity (I2 = 32%) compared with the control in non-spinal neurosurgical operation. The intrawound vancomycin had significantly lower surgical site wound infections compared with control in non-spinal neurosurgical operation. The low sample size of 2 out of 13 researches in the meta-analysis calls for care when analysing the results.

Hybrid Lithographic Arbitrary Patterning of TiO2 Nanorod Arrays.

In this work, we report a hybrid lithographic method that combines the top-down soft lithography and the bottom-up hydrothermal approach for growing single-crystalline TiO2 nanorod arrays with arbitrary patterns. The arbitrary patterns of TiO2 seeds were obtained through the microcontact printing of the TiO2 seed precursor onto Si substrates using prepatterned poly(dimethylsiloxane) (PDMS) as stamps, followed by a baking process. Afterward, TiO2 nanorod arrays were selectively grown on patterned TiO2 seeds through conventional hydrothermal methods. By controlling the TiO2 seed precursor concentration, the hydrothermal reaction time and temperature and the patterns, the morphology and density of the TiO2 nanorods can be tuned in a controllable manner. Overall, this work provides a new strategy for the low-cost and facile preparation of patterned TiO2 nanorod arrays that has potential applications in micro-nano-optoelectronic devices and other fields.

Osteogenesis-Inducing Chemical Cues Enhance the Mechanosensitivity of Human Mesenchymal Stem Cells for Osteogenic Differentiation on a Microtopographically Patterned Surface.

Mechanical cues are widely used for regulating cell behavior because of their overarching, extensive, and non-invasive advantages. However, unlike chemical cues, mechanical cues are not efficient enough to determine cell fate independently and improving the mechanosensitivity of cells is rather challenging. In this study, the combined effect of chemical and mechanical cues on the osteogenic differentiation of human mesenchymal stem cells is examined. These results show that chemical cues such as the presence of an osteogenic medium, induce cells to secrete more collagen, and induce integrin for recruiting focal adhesion proteins that mature and cascade a series of events with the help of the mechanical force of the scaffold material. High-resolution, highly ordered hollow-micro-frustum-arrays using double-layer lithography, combined with modified methacrylate gelatin loaded with pre-defined soluble chemicals to provide both chemical and mechanical cues to cells. This approach ultimately facilitates the achievement of cellular osteodifferentiation and enhances bone repair efficiency in a model of femoral fracture in vivo in mice. Moreover, the results also reveal these pivotal roles of Integrin α2/Focal adhesion kinase/Ras homolog gene family member A/Large Tumor Suppressor 1/Yes-associated protein in human mesenchymal stem cells osteogenic differentiation both in vitro and in vivo. Overall, these results show that chemical cues enhance the microtopographical sensitivity of cells.

Cyanidin-3-glucoside suppresses the progression of lung adenocarcinoma by downregulating TP53I3 and inhibiting PI3K/AKT/mTOR pathway.

BACKGROUND: The aim of this study is to unravel the role of Cyanidin-3-glucoside (C3G) and its potential mechanisms in lung adenocarcinoma (LUAD). METHODS: The cell clones, proliferation, apoptosis, migration, and invasion in H1299 and A549 cells were determined by colony formation assay, 5-ethynyl-20 deoxyuridine (EdU) assay, flow cytometry, and transwell assay, respectively. The expression of p53-induced gene 3 (TP53I3) was assessed and the prognostic values of TP53I3 in LUAD via the dataset from the Cancer Genome Atlas (TCGA). In addition, the mRNA and protein expressions were detected by quantitative real-time PCR (qRT-PCR) and western blot. RESULTS: C3G inhibited the proliferation, migration, and invasion of, and also promoted the apoptosis in H1299 and A549 cells. The database of TCGA showed TP53I3 was highly expressed in LUAD tissues and correlated with the poor prognosis of LUAD patients. Moreover, we also found that C3G inhibited the proliferation, migration and invasion, and promoted apoptosis in H1299 and A549 cells by downregulating TP53I3. Additionally, C3G could inhibit the activation of phosphatidylinositol 3'-kinase (PI3K)/protein kinase B (AKT)/mammalian target of rapamycin (mTOR) pathway in H1299 and A549 cells by downregulating TP53I3. CONCLUSION: This study demonstrated that C3G could inhibit the proliferation, migration and invasion, and also facilitate the apoptosis through downregulating TP53I3 and inhibiting PI3K/AKT/mTOR pathway in LUAD.

Single-Step Dual-Layer Photolithography for Tunable and Scalable Nanopatterning.

Conventional photolithography, due to its scalability, robustness, and straightforward processes, has been widely applied to micro- and nanostructure manufacturing in electronics, optics, and biology. However, optical diffraction limits the ultimate resolution of conventional photolithography, which hinders its potential in nanoscale patterning for broader applications. Here, we introduce a derivative of conventional photolithography for nanoscale patterning called dual-layer photolithography (DLPL), which is based on the controlled exposure and development of overlapping positive and negative photoresists. In a typical experiment, substrates are sequentially coated by two layers of photoresists (both positive and negative). Then, we purposefully control the exposure time to generate slightly larger features in the positive photoresist than those in the negative photoresist. After development, their overlapping areas become the final features, which outline the original features. We demonstrate line widths down to 300 nm here, which can be readily improved with more precise control. By adjusting the lithography parameters and material deposition, the feature sizes, shapes (e.g., rings, numbers, letters), line widths (300-900 nm), and materials (e.g., SiO2, Cr, and Ag) of these features can be independently controlled. Combined with anisotropic etching, more complex three-dimensional nanostructures can be fabricated as well, as we demonstrate here with Si. We further fabricate photodetectors as an example application to show that these nanostructures fabricated by DLPL can be used to promote light-trapping MAPbI3 perovskite films to achieve good photoelectric properties. This strategy is not limited to ultraviolet photolithography and may also be incorporated into other energetic beam-based lithographic approaches, including deep and extreme ultraviolet photolithographies and electron beam lithography, to enhance their resolution.

MrPEX33 is involved in infection-related morphogenesis and pathogenicity of Metarhizium robertsii.

Peroxisomes, being indispensable organelles, play an important role in different biological processes in eukaryotes. PEX33, a filamentous fungus-specific peroxin of the docking machinery of peroxisomes, is involved in the virulence and development of other fungal pathogens. However, it is not clear whether PEX33 is necessary for the pathogenicity and development of an insect pathogenic fungus. In the present study, we report the presence of homologs of PEX33, namely MrPEX33 (MAA_05331), in the entomopathogenic fungus, Metarhizium robertsii. An M. robertsii transgenic strain expressing the fusion protein with MrPEX33-GFP and mCherry-PTS1 showed that MrPEX33 localizes to peroxisomes. The results also demonstrated that MrPEX33 is involved in the peroxisomal import pathway by peroxisomal targeting signals. Targeted gene deletion of MrPEX33 led to a significant decline in the asexual sporulation capacity, which was accompanied by downregulation of several conidiation-associated genes, such as wetA, abaA, and brlA. More importantly, our bioassay results showed that the virulence of ∆MrPEX33 mutants, against Galleria mellonella through cuticle infection, was greatly reduced. This was further accompanied by a significant drop in appressorium formation and cuticle penetration. Additionally, ∆MrPEX33 mutants showed a significant decrease in tolerance to cell wall integrity and oxidative stress. Taken together, our results suggest that MrPEX33 is involved in the cuticle infection-related morphogenesis and pathogenicity. KEY POINTS: • MrPEX33 is a specific peroxin of the docking machinery of peroxisomes. • MrPEX33 localizes to peroxisomes and is involved in the import of matrix proteins. • MrPEX33 is involved in the pathogenicity associated with cuticle infections.

A Microchannel-Confined Crystallization Strategy Enables Blade Coating of Perovskite Single Crystal Arrays for Device Integration.

Perovskite single crystals (PSCs) possess superior optoelectronic properties compared to their corresponding polycrystalline films, but their applications of PSCs in high-performance, integrated devices are hindered by their heavy thickness and difficulty in scalable deposition. Here, a microchannel-confined crystallization (MCC) strategy to grow uniform and large-area PSC arrays for integrated device applications is reported. Benefiting from the confinement effect of the microchannels, solution flow dynamics is well controlled, and thus uniform deposition of PSC arrays with suitable thickness is achieved, meaning they are applicable for scale-up device applications. The resulting PSCs possess excellent optoelectronic properties in terms of a long carrier lifetime (175 ns) and an ultralow defect density (2 × 109 cm-3 ), which are comparable to the corresponding bulk crystals. The unique embedded structure of PSCs within the microchannels allows the construction of a high-integration image sensor. This work paves the way toward high-throughput growth of PSCs for integrated optoelectronic devices.

pH and redox dual responsive carrier-free anticancer drug nanoparticles for targeted delivery and synergistic therapy.

Advanced drug delivery systems often employ nanomaterials as carriers to deliver drugs to desirable disease sites for enhanced efficacy. However, most systems have low drug loading capacity and cause safety concerns. Therefore, many anticancer therapeutics have recently been assembled to NPs form without using any additional nanocarrier to achieve high drug loading. However, carrier-free nanomedicines are often constrained by limitations such as inadequate stability and lack of control in drug release. Therefore, we synthesize carrier-free drug NPs containing cis-aconitic anhydride-modified doxorubicin and paclitaxel (CAD-PTX) and coating with crosslinked (CL) surfactant based on hyaluronic acid (HA) segment. With this design, the pure drug NPs possess pH and redox dual responsive release characteristic and could target CD44 overexpressed cancer cells. Our studies demonstrate that these CAD-PTX-CLHA NPs display high stability, excellent active targeting effect and controllable intracellular drug release, and ultimately achieve significantly better anti-cancer efficiency than individual doxorubicin and paclitaxel.

Dual-Band, High-Performance Phototransistors from Hybrid Perovskite and Organic Crystal Array for Secure Communication Applications.

High-performance phototransistors made from organic semiconductor single crystals (OSSCs) have attracted much attention due to the high responsivity and solution-processing capability of OSSCs. However, OSSC-based phototransistors capable of dual-band spectral response remain a difficult challenge to achieve because organic semiconductors usually possess only narrow single-band absorption. Here, we report the fabrication of high-performance, dual-band phototransistors from a hybrid structure of a 2,7-dioctyl[1]benzothieno[3,2- b][1]benzothiophene (C8-BTBT) single-crystal array coated with CH3NH3PbI3 nanoparticles (NPs) synthesized by a simple, one-step solution method. In contrast to C8-BTBT and CH3NH3PbI3 NPs with respective absorption in the ultraviolet (UV) and visible (vis) region, their hybrid structure shows broad absorption covering the entire UV-vis range. The hybrid-based phototransistors exhibit an ultrahigh responsivity of >1.72 × 104 A/W in the 252-780 nm region, which represents the best performance for solution-processing, broadband photodetectors. Moreover, integrated phototransistor circuitries from the hybrid CH3NH3PbI3 NPs/C8-BTBT single-crystal array show applications for high-security communication.

Precise Patterning of Laterally Stacked Organic Microbelt Heterojunction Arrays by Surface-Energy-Controlled Stepwise Crystallization for Ambipolar Organic Field-Effect Transistors.

Ambipolar organic field-effect transistors (OFETs) combining single-crystalline p- and n-type organic micro/nanocrystals have demonstrated superior performance to their amorphous or polycrystalline thin-film counterparts. However, large-area alignment and precise patterning of organic micro/nanocrystals for ambipolar OFETs remain challenges. Here, a surface-energy-controlled stepwise crystallization (SECSC) method is reported for large-scale, aligned, and precise patterning of single-crystalline laterally stacked p-n heterojunction microbelt (MB) arrays. In this method, the p- and n-type organic crystals are precipitated via a stepwise process: first, the lateral sides of prepatterned photoresist stripes provide high-surface-energy sites to guide the aligned growth of p-type organic crystals. Next, the formed p-type crystals serve as new high-surface-energy positions to induce the crystallization of n-type organic molecules at their sides, thus leading to the formation of laterally stacked p-n microbelts. Ambipolar OFETs based on the p-n heterojunction MB arrays exhibit balanced hole and electron mobilities of 0.32 and 0.43 cm2 V-1 s-1 , respectively, enabling the fabrication of complementary-like inverters with large voltage gains. This work paves the way toward rational design and construction of single-crystalline organic p-n heterojunction arrays for high-performance organic, integrated circuits.

Saturated Vapor-Assisted Growth of Single-Crystalline Organic-Inorganic Hybrid Perovskite Nanowires for High-Performance Photodetectors with Robust Stability.

One-dimensional organic-inorganic hybrid perovskite nanowires (NWs) with well-defined structures can possess superior optical and electrical properties for optoelectronic applications. However, most of the current perovskite NWs are prepared in the air, making the perovskite NWs vulnerable to moisture and resulting in large amounts of grain boundaries (GBs)/surface defects on NWs. Here, we report the use of an isolated growth environment (organic solvent vapor atmosphere), termed saturated vapor-assisted crystallization method, to fabricate high-quality single-crystalline CH3NH3PbI3 NWs. The NWs have smooth surface with few GBs and surface defects because of the elimination of moisture intrusion in the vapor atmosphere. Significantly, photodetectors based on the as-prepared single-crystalline CH3NH3PbI3 NWs demonstrated an extremely high photoresponsivity up to 460 A/W, an ultrafast response time of ∼180 us, a large specific detectivity of 2.6 × 1013 jones, as well as an improved stability in air over 45 days. The device performance is among the best in the CH3NH3PbI3 NW-based devices. Kelvin probe force microscopy investigation further offered an insight into the excellent photoconductive properties of the CH3NH3PbI3 NWs. This work paves the way toward the fabrication of high-performance nano-optoelectronic devices based on the high-quality organic-inorganic hybrid perovskite CH3NH3PbI3 NWs.

Doxorubicin@Bcl-2 siRNA Core@Shell Nanoparticles for Synergistic Anticancer Chemotherapy.

Acquired drug resistance in malignant tumors seriously hinders effective chemotherapy against cancer. The main mechanisms of drug resistance include decreased drug influx, increased drug efflux, as well as antiapoptotic defense behavior in cancerous cells. To overcome these issues, we have designed a nanomedicine composed of pure doxorubicin (DOX) as the core and B-cell lymphoma-2 (Bcl-2) siRNA as the shell for synergistic cancer treatment. Between the core and shell, polyethylene glycol (PEG) and polyethylenimine (PEI) are employed to increase the stability of the core DOX NPs and facilitate siRNA coating, respectively. In this design, the siRNA is able to inhibit the expression of Bcl-2 protein which has a role of protecting cancer cells from apoptosis. DOX not only is for anticancer therapy but also acts as a nanocarrier for Bcl-2 siRNA delivery. Our studies show that Bcl-2 siRNA and DOX are efficiently delivered into tumor cells and tumor tissues, and such a codelivery nanosystem possesses synergistic effects on tumor inhibition, enabling significantly enhanced antitumor outcome. This work demonstrates that the codelivery of tumor-suppressive Bcl-2 siRNA and chemotherapeutic agents without using an excipient material as a drug carrier represents a promising therapy for enhanced cancer therapy.