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Kinetic analysis of the growth of perovskite CsPbBr3 nanocrystals synthesized in a microfluidic system; correlation among the bandgap, total flow rate (growth time) and synthesis temperature.

A microfluidic platform is used to synthesize blue-emitting lead-free Cs2SnCl6 microcrystals with water as a solvent at room temperature. The Cs2SnCl6 nanocrystals derived from the microcrystals have a remarkable long-term optical stability over 60 days.

NF-κB and Notch signaling can be simultaneously activated in a variety of B-cell lymphomas. Patients with B-cell lymphoma occasionally develop clonally related myeloid tumors with poor prognosis. Whether concurrent activation of both pathways is sufficient to induce B-cell transformation and whether the signaling initiates B-myeloid conversion in a pathological context are largely unknown. Here, we provide genetic evidence that concurrent activation of NF-κB and Notch signaling in committed B cells is sufficient to induce B-cell lymphomatous transformation and primes common progenitor cells to convert to myeloid lineage through dedifferentiation, not transdifferentiation. Intriguingly, the converted myeloid cells can further transform, albeit at low frequency, into myeloid leukemia. Mechanistically, coactivation of NF-κB and Notch signaling endows committed B cells with the ability to self renew. Downregulation of BACH2, a lymphoma and myeloid gene suppressor, but not upregulation of CEBPα and/or downregulation of B-cell transcription factors, is an early event in both B-cell transformation and myeloid conversion. Interestingly, a DNA hypomethylating drug not only effectively eliminated the converted myeloid leukemia cells, but also restored the expression of green fluorescent protein, which had been lost in converted myeloid leukemia cells. Collectively, our results suggest that targeting NF-κB and Notch signaling will not only improve lymphoma treatment, but also prevent the lymphoma-to-myeloid tumor conversion. Importantly, DNA hypomethylating drugs might efficiently treat these converted myeloid neoplasms.

Printable perovskite quantum dot (QD) ink is very important for achieving high quality coffee ring-free fluorescent microarrays for different kinds of emerging perovskite optoelectronic applications using inkjet printing. In this work, we prepared a printable CsPbBr3 perovskite QD ink by mixing high-boiling point dodecane with low-boiling point toluene as a solvent. The evaporation rate, viscosity and surface tension of the ink were carefully optimized by tuning the volume ratio of these two solvents for forming appropriate Marangoni flow, so as to balance the capillary flow and eliminate the coffee ring effect further. Successfully, CsPbBr3 perovskite microarrays with uniform surface, low roughness and no coffee rings were achieved by inkjet printing the optimized perovskite QD ink on a PVK (poly-(9-vinylcarbazole)) layer. Furthermore, we patterned the CsPbBr3 perovskite QD ink, and the printed patterns were only visible under ultraviolet (UV) light, which can be applied in invisible anti-counterfeiting labels and encryption in the future.

As a practical advanced oxidation process with high-efficiency, ferrous-activated peroxymonosulfate (PMS) technology has been extensively investigated and employed for the degradation of organic substances in water treatment process. However, to our best of knowledge, few studies in applying ferrous-activated PMS as the pretreatment for nanofiltration process have been conducted and the mechanisms of membrane fouling alleviation due to ferrous-activated PMS was still unclear. Consequently, ferrous-activated PMS approach was innovatively adopted as pretreatment for nanofiltration in present study, compared with the conventional pretreatment process (coagulation). The results indicated that both strategies could significantly mitigate organic fouling at membrane surface, but the gypsum scaling was enhanced when Fe(II)/PMS was adopted prior to nanofiltration process at the dose of 80/80 μM, because of the assistance of ferric ions and sulfate anions. ATR-FTIR spectra indicated that the greater alleviation of flux decline caused by Fe(II)/PMS oxidation was attributed to the less accumulation of organic substances on membrane surface, relative to the conventional Fe(III) coagulation. Furthermore, Xtended Derjaguin-Landau-Verwey-Overbeek (XDLVO) theory was utilized to explain the greater interfacial free energy of adhesion (equal to decreased repulsion or increased attraction) between foulants and nanofiltration membranes in ferrous-activated PMS strategies joined nanofiltration process. Interestingly, Fe(II)/PMS oxidation could efficiently improve the quality of effluent in nanofiltration process, and three-dimension excitation emission matrix fluorescence spectroscopy (3D-EEM) spectra demonstrated that Fe(II)/PMS conferred higher removals of organic substances. The removal efficiency of Bisphenol A in Fe(II)/PMS assisted nanofiltration process varied from 53% to 78%, while only 5–12% Bisphenol A was removed in Fe(III) coagulation joined system. Besides, the potential mechanisms of flux decline caused by individual and combined organic substances were also investigated. Therefore, the findings in present study would contribute to the deep understanding of membrane fouling mechanism and promote the practical application of nanofiltration technologies.

The study objective was to investigate the role of fibroblast growth factor 9 (Fgf9) in normal and anorectal malformation (ARM) embryos during the development of the anorectum. Fgf9 expression was assayed in both normal rat embryos and embryos with ARM induced by exposure to ethylenethiourea (ETU) on embryonic day 10 (E10). Fgf9 expression was assayed by immunohistochemical staining, Western blotting, and real-time quantitative polymerase chain reaction (qRT-PCR). Immunohistochemical staining revealed spatiotemporal changes in Fgf9 expression between E13 and E16. Fgf9-positive cells predominated in the mesenchyme of the cloaca on E13 and E14 and at the fusion site of the urorectal septum and cloacal membrane, rectal epithelium, and anal membrane on E15. Fgf9-positive cells were obviously decreased after the anal membrane ruptured on E16. Fgf9-positive staining was significantly decreased in embryos with ARM compared with normal embryos from E13 to E15. The results of Western blots and qRT-PCR were consistent, with significantly increased Fgf9 expression in the hindgut and rectum of normal embryos than in embryos with ARM from E13 to E15. However, there was no difference between the two groups on E16. These results suggested that the anorectal embryogenesis might depend on the induction of Fgf9 signal. The expression of Fgf9 was downregulated in ETU-induced ARM embryos, which might be related to the development of ARM.

“The Answer,” a poem by Bei Dao first published in 1978, marks the emergence of a defiant voice in contemporary Chinese poetry and asserts skepticism as the political stance of a young generation in post–Cultural Revolution China. It also heralds a historic transition from an era of sonic agitation to an aesthetics based on visual perception and contemplation. This rereading of Bei Dao's canonical poem and other related texts goes back to the late 1970s, when the political implications of the human senses were firmly grasped and heatedly debated. The author shows that an ocular turn occurs in “The Answer” and drives the aesthetic as well as political pursuits of a new generation of poets. He further argues that, in a moment still enthralled with a revolutionary sonic culture, Misty poetry disavowed aural excitement and was part of the reconditioning of the human senses in preparation for a postrevolutionary order and sensibility.

In this work, we develop an environmental-friendly approach to produce organic-inorganic hybrid MAPbBr3 (MA = CH3NH3) perovskite nanocrystals (PeNCs) and PMMA-MAPbBr3 NC films with excellent compression-resistant PL characteristics. Deionized water is used as the solvent to synthesize MAPbBr3 powder instead of conventionally-used hazardous organic solvents. The MAPbBr3 PeNCs derived from the MAPbBr3 powder exhibit a high photoluminescence quantum yield (PLQY) of 93.86%. Poly(methyl methacrylate) (PMMA)-MAPbBr3 NC films made from the MAPbBr3 PeNCs retain ∼97% and ∼91% of initial PL intensity after 720 h aging in ambient environment at 50 °C and 70 °C, respectively. The PMMA-MAPbBr3 NC films also exhibit compression-resistant photoluminescent characteristics in contrast to the PMMA-CsPbBr3 NC films under a compressive stress of 1.6 MPa. The PMMA-MAPbBr3 NC film integrated with a red emissive film and a blue light emitting source achieves an LCD backlight of ∼114% color gamut of National Television System Committee (NTSC) 1953 standard.

With the comprehensive development of the smart grid, along with the large amount of operational data generated by the operation of the power grid, a lot of attention has been paid to the short-text information about the secondary electrical equipment failures that have occurred. This article analyzes the fault data that occurs during the operation of the secondary equipment. With reference to the general process of Chinese natural language processing, considering the overall characteristics of the fault information, the LDA topic model is used to generate a topic text model of short text data. For local features, use the Word2Vec word vector model is used for characterization. Finally, convolutional neural network (CNN) is used to categorize the fault categories of the information, and a short text classification model of secondary equipment in smart grid based on the LDA topic model and CNN is proposed. The example results show that the proposed Chinese short text classification model can improve the classification accuracy, and the classification effect is also considerable.

Due to the asymmetry of the traction transformer, there is a problem in the calculation of the measured impedance when the line distance protection on the grid side cooperates with the traction transformer, which causes problems for the setting calculation personnel whether the distance protection can avoid the faults on the other side of the traction transformer. Firstly, the influence of traction substation on distance protection is studied and analyzed. Secondly, the analysis models of single-phase Ii traction transformer, V/v wiring traction transformer and V/x wiring traction transformer are built. Finally, the measurement impedance correction scheme of the protection on the grid side distance after the other side faults of traction transformer is analyzed, and the setting calculation proposal of distance protection is given.

Printable perovskite quantum dot (QD) ink is very important for achieving high quality coffee ring-free fluorescent microarrays for different kinds of emerging perovskite optoelectronic applications using inkjet printing. In this work, we prepared a printable CsPbBr

The dynamics of hot electrons in metal including generation, transport and injection have been studied theoretically and experimentally. Substrate-side illumination is demonstrated to effectively improve the performance of hot electrons photodetectors. © 2020 The Author(s)

Heterotopic pancreas (HP) is a congenital anomaly defined as pancreatic tissue that has no contact with the orthotopic pancreas and its own duct system and vascular supply. The most common locations of HP are the upper gastrointestinal tract, specifically, the stomach, duodenum, and proximal jejunum. Involvement of the mesentery is rare. Here, we describe a rare case of mesenteric heterotopic pancreas (MHP) in a 12-year-old girl who presented with acute abdomen. The patient underwent emergency laparotomy, and the mass and adjacent small bowel were resected. Results of the postoperative histopathologic examination confirmed the diagnosis of MHP. Observation of the patient for 12 mo postoperatively showed no evidence of recurrence. Preoperative diagnosis of HP is difficult, even in a symptomatic patient. Increased awareness and understanding of the image characteristics of MHP will aid in correct preoperative diagnosis and appropriate patient management.

Perovskite nanocrystals are regarded as next-generation functional materials for display applications, especially for flexible liquid crystal displays (LCDs). As a potential component of flexible LCD backlights, perovskite nanocrystal films are facing a challenge issue of deformation-induced shift of photoluminescence, leading to an image distortion. To date, most synthesis methods have involved the use of organic solvent in precursor solutions, such as N,N-dimethylformamide and dimethyl sulfoxide, which poses a potential threat to the environment, health and security. In this work, we demonstrate the feasibility to produce microsized CsPbBr3 crystals with deionized water as the precursor solvent via an environmental-friendly and cost-efficient approach and CsPbBr3 nanocrystals with green (~522 nm) and blue (~493 nm) emissions from the microsized CsPbBr3 crystals in toluene under sonication. The blue-emitting nanocrystals exhibit a photoluminescence (PL) quantum yield of 80%, much larger than 61.4% of the CsPbBr3 nanocrystals made by an anti-solvent method; the green-emitting nanocrystals exhibit better stability than those made by the antisolvent method over 9 days. Using the green-emitting CsPbBr3 nanocrystals, we prepare a bilayer structure with a poly(methyl methacrylate)-CsPbBr3 nanocrystal film on a polyethylene terephthalate plate. The films exhibit bending-endurable photoluminescence, i.e. the wavelength of the PL peak remains unchanged, for local radius of curvature of the bilayer up to 10.07 mm under bending. This study opens a new avenue to potentially produce microsized perovskite crystals without harmful organic solvents and bending-endurable backlight films for the applications in flexible display.

A novel silica nanowire-silica composite aerogels with excellent thermal insulation and mechanical properties was prepared by adding SiO2 nanowires as a secondary phase into the silica matrix and drying at ambient pressure. The SiO2 nanowires and silica aerogel matrix have outstanding compatibility and dispersibility because the components of nanowire and aerogel matrix all are silica, which contributes to the improvement of the mechanical property of the silica composite aerogels. The physical, mechanical and thermal properties of the SiO2 nanowires based composite silica aerogel are investigated and discussed in detail. The results indicate that the monolithic aerogels with high specific surface area, porosity and large pore volume. The thermal conductivity of the composite silica aerogels only increases gently (0.006 W·m−1 K−1) as the addition of SiO2 nanowires rises from 0 wt% to 14 wt%, while their mechanical properties have been improved greatly. The SiO2 nanowires based composite silica aerogel would be widely used in the thermal insulation application because of its outstanding thermal insulation property. Keywords: Silica aerogel, Porous materials, Thermal insulation, SiO2 nanowires, Ambient pressure drying

Current research into the causes of macro-cracks in the debinding of light-cured ceramic body is predominantly focused on heating rate and holding time. In this paper, we propose a novel approach to analyze the causes of defects in the ceramic body during the debinding process via the interconnected channels formed in the process of the binder discharged from the inside to the outside. The physical and chemical changes, and related reaction products of the binder were analyzed by the TG-FTIR using a specific resin as the binder in the low temperature debinding stage (200–300 °C) and high temperature debinding stage (300–600 °C). Based on the result, a novel approach is proposed to illustrate the process of the formation of interconnected channels and defects. The samples of green bodies debond at different holding time were analyzed by the SEM and μ-CT. The experimental results prove the formation of interconnected channels, and it is found that the holding temperature of 237 °C is favorable for the formation of the channel and the discharge of the gas products. The defect-free samples after low temperature debinding process were debond in the high temperature debinding process at three different holding temperatures of 360 °C, 430 °C, and 550 °C obtained by analyzing the DTG curve and the absorption curve of CO2 in the infrared spectrum, and samples after high temperature debinding process were analyzed by the SEM and μ-CT. The experimental results show that these holding temperatures favor the stable discharge of CO2 and the binder pyrolysis products from the channels, thereby avoiding cracks due to severe gas expansion. The research results in this paper have important reference value for the preparation of defect-free ceramic samples.

Background: To assess the expression of T-box transcription factor 4 (TBX4) during the anorectal development in normal and ethylenethiourea (ETU)-induced anorectal malformations (ARM) rat embryos. Methods: Anorectal malformations was induced by ETU on the 10th gestational day (E10) in rat embryos. Spatiotemporal expression of TBX4 was evaluated in normal (n = 490) and ETU-induced ARM rat embryos (n = 455) from E13 to E16 by immunohistochemical staining, Western blot analysis and real-time RT-PCR. Results: In the normal embryos, immunohistochemical staining revealed that TBX4 expression was detected in the epithelium of hindgut and urorectal septum (URS) on E13. TBX4-immunopositive cells were increased significantly in the epithelium of hindgut and URS, the future anal orifice part of cloacal membrane on E14. On E15, abundant stained cells were observed in the rectum, URS and dorsal cloacal membrane and the expression of positive cells reached its peak. On E16, only sporadic positive cells were distributed in the epithelium of the distal rectum. In the ARM embryos, the hindgut/rectum, URS and dorsal cloacal membrane were faint for TBX4 immunohistochemical staining. In the normal group, TBX4 protein and mRNA expression showed time-dependent changes in the hindgut/rectum from E13 to E16 on Western blot and real-time RT-PCR. On E13 and E15, the expression level of TBX4 mRNA in the ARM group was significantly lower than that in the normal group (P < 0.05). On E15, the expression level of TBX4 protein in the ARM group was significantly lower than that in the normal group (P < 0.05). Conclusions: The expression of TBX4 was downregulated in ETU-induced ARM embryos, which may play important roles in the pathogenesis of anorectal development.

This chapter describes the social reality that the new market economy helps to dismantle as either the "traditional socialist system" or simply the "traditional system." This traditional social organization valorizes communality, hierarchy, and ideological homogeneity, all of which contribute to an impoverishment of everyday life. There is no question that in contemporary China a market economy is finally prevailing and with irresistible force is penetrating into every fiber of social life, fueling an explosive capitalist Great Leap Forward far unmatched in modern Chinese history. The complexity of the situation can hardly be understood simply in terms of the marketization of a centrally planned economy in general and ideologically controlled cultural production in particular. The emergent urban culture exhibits many recognizable features of modern metropolises in the West. Everyday urban life as normalcy seems quite successfully instituted and, for good reason, this is celebrated as a genuine cultural revolution in contemporary China.

Background Quantitative real-time polymerase chain reaction (RT-qPCR) is a sensitive method for quantifying mRNA abundance. With relative expression analysis, however, reliable data output is dependent on stably expressed reference genes across the samples being studied. In anorectal malformations (ARMs), there is limited data on the selection of appropriate reference genes. Purpose This study was aimed to investigate the optimal reference genes for PCR in ARM rat models. Methods We selected 15 commonly used reference genes (Rps18, Actb, B2m, Gapdh, Ppia, Hprt1, Pgk1, Ywhaz, Tbp, Ubc, Rps16, Rpl13a, Rplp1, Sdha, and Hmbs) as candidate reference genes and detected their mRNA expression in ARM samples by RT-qPCR. The expression stability and variability of these transcripts were subsequently evaluated using four methods (geNorm, NormFinder, comparative ΔCt, and BestKeeper). Results The abundance of the candidate reference genes was qualified by RT-qPCR and the cycle threshold (Ct) values ranged between 14.07 (Rplp1) and 21.89 (Sdha). In the overall candidate genes, different variations existed across the different algorithms. A comprehensive analysis revealed that Rpl13a ranked first among the relatively stable genes, followed by Ywhaz, Rps18, Sdha, and Hmbs. Conclusions The most stable reference genes for RT-qPCR were Rpl13a, Ywhaz, and Rps18 in ETU-induced ARMs in rat fetus. This study provided a foundation for reference gene selection for future gene expression analyses.

Bulk scintillators that are with high density, low cost, and fine pulse-height energy spectral resolution, and are non-hygroscopic and user friendly, are desired for high-energy gamma-ray spectroscopy application. Recently, low-cost solution-processed perovskite nanoscintillators have been demonstrated with outstanding performances for indirect low-energy X-ray detection; however, the stability and thickness are not suitable for high-energy gamma-ray detection. Here, we report scintillation performances of a low-cost solution-processed bulk 0D Cs 3 Cu 2 I 5 single crystal. The self-trapped exciton emission results in a large Stokes shift (109 nm) that is reabsorption free. A broad X-ray excited emission matches well with the sensitivity of a silicon photodiode. The unique Cs + surrounded isolated [ Cu 2 I 5 ] 3 − cluster scintillator provides ultra-stability in air and strong radiation hardness under high-dose gamma-ray exposure from a 60Co source. This solution-processed Cs 3 Cu 2 I 5 scintillator is expected with low-cost and has detection performances comparable to commercial alkali-halide scintillator products.

Colloidal quantum dots (CQDs) are promising materials for developing infrared (IR) detectors. Absorption spectra and spectral photoresponse can be continuously tuned by controlling the size, shape, and composition of CQDs. However, the incapability to achieve site-selective patterning of CQDs by conventional methods (i.e., drop casting, spin coating, and spray coating) greatly hinders the realization of CQD-based multipixel or multispectral detectors. In this paper, we demonstrate a simple and highly efficient poly(methyl methacrylate)-assisted transfer technique for the scalable fabrication of CQD-based photodetectors with multiple pixels, which respond to different spectral ranges of IR, by using patterned HgTe CQD films. Large arrays of three-pixel photodetectors were produced on both flat and curved substrates with a high fabrication success rate of over 95%. The maximum room-temperature responsivity of up to 0.1 A/W under low operation voltage (