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0D hybrid metal halides (0D HMHs) with fully isolated inorganic units provide an ideal platform for studying the correlations between chiroptical activities and crystal structures at atomic levels. Here, through the incorporation of different solvent molecules, a series of 0D chiral manganese bromides (RR/SS-C20H28N2)3MnBr8·2X (X = C2H5OH, CH3OH, or H2O) are synthesized to elucidate their chiroptical properties. They show negligible circular dichroism signals of Mn absorptions due to C2v-symmetric [MnBr4]2- tetrahedra. However, they display distinct circularly polarized luminescence (CPL) signals with continuously increased luminescence asymmetry factors (glum) from 10-4 (X = C2H5OH) to 10-3 (X = H2O). The increased glum value is structurally revealed to originate from the enhancement of [MnBr4]2- tetrahedral bond-angle distortions, due to the presence of different solvent molecules. Furthermore, (RR/SS-C20H28N2)MnBr4·H2O enantiomers with larger bond-angle distortions of [MnBr4]2- tetrahedra are synthesized based on hydrobromic acid-induced structural transformation of (RR/SS-C20H28N2)3MnBr8·2H2O enantiomers. Therefore, such (RR/SS-C20H28N2)MnBr4·H2O enantiomers exhibit enhanced CPL signals with |glum| up to 1.23 × 10-2. This work provides unique insight into enhancing chiroptical activities in 0D HMH systems.
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Ultraviolet circularly polarized luminescence (UV-CPL) with high photon energy shows great potential in polarized light sources and stereoselective photopolymerization. However, developing luminescent materials with high UV-CPL performance remains challenging. Here, we report a pair of rare earth Ce3+-based zero-dimensional (0D) chiral hybrid metal halides (HMHs), R/S-(C14H24N2)2CeBr7, which exhibits characteristic UV emissions derived from the Ce 5d-4f transition. The compounds show simultaneously high photoluminescent quantum yields of (32-39)% and large luminescent dissymmetry factor (|glum|) values of (1.3-1.5)×10-2. Thus, the figures of merits of R/S-(C14H24N2)2CeBr7 are calculated to be (4.5-5.8)×10-3, which are superior to the reported UV-CPL emissive materials. Additionally, nearly 91 % of their PL intensities at 300â K can be well preserved at 380â K (LED operating temperature) without phase transition or decomposition, demonstrating the excellent structural and optical thermal stabilities of R/S-(C14H24N2)2CeBr7. Based on these enantiomers, the fabricated UV-emitting CP-LEDs exhibit high polarization degrees of ±1.0 %. Notably, the UV-CPL generated from the devices can significantly trigger the enantioselective photopolymerization of diacetylene with remarkable stereoselectivity, and consequently yield polymerized products with the anisotropy factors of circular dichroism (gCD) up to ±3.9×10-2, outperforming other UV-CPL materials and demonstrating their great potential as UV-polarized light sources.
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In this study, asymmetric Al2O3-SiO2 Janus nanoparticles with a dumbbell-like structure were synthesized by a facile chemical process in the aqueous phase. Prior to synthesis, Al2O3 nanoparticles in hydrosol were amino-modified using 3-aminopropyl triethoxysilane (KH550) and then carboxyl acid-functionalized using a ring-opening reaction of the amine functions with succinic anhydride, imparting unique anionic properties to the Al2O3 end. SiO2 nanoparticles were rendered hydrophobic through modification with hexamethyldisilazane (HMDS) and further functionalized with 3-chloropropyl triethoxysilane (KH230). The two nanoparticle hydrosols were then mixed, and the asymmetric Al2O3-SiO2 Janus nanoparticles were synthesized via the reaction between the -NH2 and -CH2Cl groups. The prepared Janus nanoparticles were primarily characterized by dynamic light scattering (DLS), Zeta potential (ZP), and transmission electron microscopy (TEM). The results indicated that about 90% of the modified Al2O3 and SiO2 nanoparticles were covalently coupled in a one-to-one manner to form the dominant dumbbell-like structure. These Janus nanoparticles exhibit amphiphilic properties, making them highly promising surfactants for emulsifying oil-water mixtures.
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Water-soluble polysaccharides (WSP) were extracted from the pulp of litchi. Its main component was identified as arabinogalactan. The dominant monosaccharide constituents were arabinose and galactose. Galactose and mannose accumulated at the end of storage. ATP, ADP and AMP levels declined with increasing pulp breakdown index. WSP depolymerized which was characterized by a decrease in its content and molecular weight, while its structure remained stable during storage. Polygalacturonase and pectate lyase (PL) were active at the early storage time, and ß-galactosidase (GAL) and α-l-arabinofuranosidase followed thereafter. Except for some pectin methylesterase (LcPME), LcPL, LcGAL and LcPME gene expression was downregulated. It was deduced that depolymerization of polysaccharides was mainly caused by the rupture of the branched side chain and glacturonic acid backbone to smaller repeating units, and both cell wall-degrading enzymes and nonenzymatic factors, such as energy level, participated in the degradation of polysaccharides, and consequently pulp breakdown of litchi.
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Litchi , Litchi/química , Poligalacturonasa/metabolismo , Arabinosa/análisis , Agua/análisis , Galactosa/análisis , Manosa/metabolismo , Polisacáridos/química , Frutas/química , Monosacáridos/análisis , beta-Galactosidasa/metabolismo , Adenosina Difosfato/metabolismo , Adenosina Monofosfato/análisis , Adenosina Trifosfato/metabolismoRESUMEN
PURPOSE: Cataract surgery in patients with nanophthalmos is complicated for ophthalmologists to perform. Due to the unique ocular anatomy, there is a high incidence of complex complications such as angle-closure glaucoma, fluid misdirection syndrome, and uveal effusion syndrome (UES) in the perioperative period of cataract surgery. This article will discuss the management options for cataract surgery in nanophthalmic eyes and complications. METHODS: This review is searched through PubMed, focusing on articles published in the past 20 years. Articles were reviewed on the anatomical structure of nanophthalmic cataracts, the pathogenesis of complications, the selection of intraocular lenses, and surgical methods. CONCLUSION: There is a strong correlation between abnormal ocular anatomy and complications in patients with nanophthalmos. Clinicians must not only select the appropriate intraocular lens formula based on the depth of the anterior chamber but also formulate personalized surgical methods based on its unique anatomical structure to avoid complications.
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Extracción de Catarata , Catarata , Microftalmía , Humanos , Microftalmía/complicaciones , Microftalmía/cirugía , Agudeza Visual , Catarata/complicaciones , Extracción de Catarata/efectos adversos , Cámara Anterior , Presión IntraocularRESUMEN
Horticulture is one of the oldest agricultural practices with great popularity throughout the world. Horticultural crops include fruits, vegetables, ornamental plants, as well as medicinal and beverage plants. They are cultivated for food, specific nutrition, and medical use, or for aesthetic pleasure. MicroRNAs (miRNAs), which constitute a major class of endogenous small RNAs in plants, affect a multitude of developmental and physiological processes by imparting sequence specificity to gene regulation. Over the past decade, tens of thousands of miRNAs have been identified in more than 100 horticultural crops and their critical roles in regulating quality development of diverse horticultural crops have been demonstrated. Here, we review how miRNAs have emerged as important regulators and promising tools for horticultural crop improvement.
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MicroARNs , Agricultura , Productos Agrícolas/genética , Regulación de la Expresión Génica de las Plantas/genética , Horticultura , MicroARNs/genéticaRESUMEN
Whole-cell biosensors are useful for monitoring heavy metal toxicity in public health and ecosystems, but their development has been hindered by intrinsic trade-offs between sensitivity and specificity. Here, we demonstrated an effective engineering solution by building a sensitive, specific, and high-response biosensor for carcinogenic cadmium ions. We genetically programmed the metal transport system of Escherichia coli to enrich intracellular cadmium ions and deprive interfering metal species. We then selected 16 cadmium-sensing transcription factors from the GenBank database and tested their reactivity to 14 metal ions in the engineered E. coli using the expression of the green fluorescent protein as the readout. The resulting cadmium biosensor was highly specific and showed a detection limit of 3 nM, a linear increase in fluorescent intensities from 0 to 200 nM, and a maximal 777-fold signal change. Using this whole-cell biosensor, a smartphone, and low-tech equipment, we developed a simple assay capable of measuring cadmium ions at the same concentration range in irrigation water and human urine. This method is user-friendly and cost-effective, making it affordable to screen large amounts of samples for cadmium toxicity in agriculture and medicine. Moreover, our work highlights natural gene repositories as a treasure chest for bioengineering.
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Técnicas Biosensibles , Cadmio , Ecosistema , Escherichia coli/genética , Humanos , MetalesRESUMEN
Two new pyrrolizidine alkaloids, sclerwalins A and B (1 and 2), and one known 9-O-E-hydroxysenecioylretronecine (3) were first isolated from the seeds of Scleropyrum wallichianum. Their chemical structures were elucidated by extensive 1 D NMR and 2 D NMR (HSQC, HMBC, COSY, and ROESY), MS and IR spectra. Cytotoxicities of all isolates were evaluated against five human tumor cell lines (HL-60, A-549, SMMC-7721, MCF-7 and SW480).[Formula: see text].
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Alcaloides de Pirrolicidina , Línea Celular Tumoral , Células HL-60 , Humanos , Estructura Molecular , SemillasRESUMEN
BACKGROUND: Developmental dysplasia of the hip is a developmental abnormality of the hip joint that results from hypoplasia during birth and continues to deteriorate after birth. AIM: To observe the effects of magnesium sulfate wet compress, iodophor wet compress, and ice compress on reducing postoperative perineal swelling in children with developmental hip dislocation to provide effective nursing interventions in the clinic. METHODS: A total of 120 children with hip dislocation after surgery in a third-class A hospital from January 2018 to January 2020 were randomly divided into four groups, the magnesium sulfate wet compress group, iodophor wet compress group, ice compress group and the control group. Data such as height, weight, age, duration of surgery, intraoperative blood loss, postoperative body temperature, swelling duration, pain score, and incidence of blisters were collected and analyzed. RESULTS: There were no significant differences in height, weight, age, duration of surgery, intraoperative blood loss, and postoperative body temperature among the four groups of children. Statistical differences were observed between the intervention groups and the control group (P < 0.05). CONCLUSION: All three methods significantly reduced postoperative perineal swelling in children with developmental hip dislocation, reduced the duration of postoperative perineal swelling, reduced pain, and improved the quality of care.
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Objectives: The aim of this study was to establish a quantitative syndrome differentiation model with logistic regression analysis for phlegm and blood stasis syndrome (PBSS) in coronary heart disease (CHD) to offer methodology guidance for the quantitative syndrome differentiation of Traditional Chinese Medicine (TCM). Design: Tongue, face, and pulse information of each subject was obtained using the TCM-intelligent diagnosis instruments. Logistic regression model was used to construct the syndrome diagnosis model. The area under receiver operating characteristic curve (ROC-AUC) was used to evaluate the diagnostic value of the model. Subjects: Among the 141 subjects, 83 belonged to the PBSS group, and 58 belonged to the non-PBSS group. Results: The independent indexes used to predict PBSS in patients with CHD were length of the crack (LC) (p = 0.002), number of ecchymosis (NE) (p < 0.001), length of philtrum (LEP) (p = 0.022), and right hand pulse h1 (Rh1) (p = 0.021). The expression of combining predictor L in this study was L = LC +57.58 NE +4.53 LEP +2.68 Rh1. The ROC curve analysis indicated that the AUC values of LC, NE, LEP, and Rh1 were 0.646, 0.710, 0.619, and 0.613, respectively. The AUC = 0.825 of the syndrome diagnosis model was the largest. Conclusions: The quantitative study of TCM syndrome based on logistic regression analysis provides a good method for the objective analysis and application of TCM syndrome.
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Enfermedad Coronaria/diagnóstico , Enfermedad Coronaria/metabolismo , Medicina Tradicional China/métodos , Moco/metabolismo , Adulto , Fenómenos Biofísicos , Circulación Sanguínea , Estudios de Casos y Controles , Diagnóstico Diferencial , Femenino , Humanos , Masculino , Persona de Mediana Edad , Proyectos Piloto , Esputo/metabolismo , SíndromeRESUMEN
Outdoor cold stress often causes an undesired threat to public health, but devising an efficient strategy to achieve localized outdoor warming of the human body is still a great challenge. Polar bear pelt can absorb sunlight and reflect thermal radiation generated inside the body, which helps in adapting to the cold environment. Inspired by the radiation control strategy of the polar bear pelt, this study reports a porous Ag/cellulose/carbon nanotube (CNT)-laminated nanofiber membrane, in which one side of the cellulose basement membrane is coated with CNTs using a foam finishing process and the Ag layer is deposited on the other side by magnetron sputtering. Based on the high solar radiation absorptivity from CNT coating and the high infrared radiation reflectivity from Ag coating, the biomimetic membrane provides radiation warming by maximizing the heat input from the sun and minimizing the human radiation heat output. Because of excellent electrical conductivity, the Ag layer can work as a wearable heater to induce fast thermal response and uniform electroheating for extra warmth under a low supplied voltage. Moreover, the biomimetic membrane possesses porosity, hydrophilicity, breathability, flexibility, and mechanical stability, suggesting its huge potential for outdoor personal thermal management. Because of their versatility, the applications of the biomimetic membranes may be extended to wearable electronics, smart garments, and thermal control materials.
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Materiales Biomiméticos/química , Calor , Membranas Artificiales , Nanofibras/química , Pelaje de Animal , Animales , Diseño de Equipo , Rayos Infrarrojos , Nanotubos de Carbono/química , Plata/química , Luz Solar , UrsidaeRESUMEN
Silica coatings with continuously adjustable refractive indices and wettability properties were prepared through a sol-gel base-catalyzed process. Adjustment of the molar ratio of water (H2O) to tetraethylorthosilicate (TEOS) was utilized to change the hydrolysis degree of the precursors, and hence change the morphology of the silica particles. With the increase in the H2O/TEOS molar ratio, the morphology of the silica particles changed from a linear net-work structure to a bead-like structure and then to a granular particle structure. A particle growth mechanism was proposed and verified by characterization. As the H2O/TEOS molar ratio increased from 0.3 to 21.0, the refractive indices of the silica coatings increased from 1.132 to 1.328. Meanwhile, a varied H2O/TEOS molar ratio also modulated the surface wettability of the silica coatings. The static water angle of the silica coatings decreased from 145° to 6° by increasing the H2O/TEOS molar ratio from 0.3 to 21.0. Different hydrophilic and hydrophobic coatings could be obtained by simply controlling the H2O/TEOS molar ratio. Silica coatings with different refractive indices and hydrophobic (or hydrophilic) properties were obtained at different H2O/TEOS molar ratios.