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C-Alkyl glycosides, an important class of C-glycosides, are widely found in various drugs and natural products. The synthesis of C-alkyl glycosides has attracted considerable attention. Herein, we developed a Ni/photoredox catalyzed decarboxylative C(sp3)-C(sp3) coupling reaction of stable glycosylcarboxylic acids with simple aliphatic bromides to generate C-alkyl glycosides. The method successfully linked several functional molecular fragments (natural products or drugs) to a sugar moiety, showing the extensive application prospects of this transformation. Controlled experiments and DFT calculations demonstrated that the reaction pathway contains a free radical process, and a possible mechanism is proposed.
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We investigated the short- and long-term effects of different forage types supplemented in preweaning dairy calves on growth performance, blood metabolites, rumen fermentation, bacterial community, and milk production during first lactation. Sixty healthy 1-mo-old female Holstein calves were blocked by birth date and body weight and randomly assigned to one of 3 groups (n = 20): normal milk and pelleted starter feeding (CON), supplemented with chopped oat hay [75.0 g/d/calf (dry matter (DM) basis); OAH], or alfalfa hay [75.0 g/d/calf (DM basis); ALF]. The forage supplementation started when calves were 30 d old (D1 of the experimental period) and ended when they were 73 d old (D44 of the experimental period when calves were weaned. Milk and feed intakes and fecal consistency scores were recorded daily. Growth performance, rumen fluid, and blood samples were collected bi-weekly. After weaning, all the calves were integrated with the same barn and diets. After calving, the milk production was recorded daily. During the experimental period, the OAH group had greater solid feed and total DM intakes and greater rumen pH than the CON group (P ≤ 0.04), but had lower forage intake and crude protein digestibility than the ALF group (P ≤ 0.04). The ALF group had higher rumen pH and blood ß-hydroxybutyrate concentration (P ≤ 0.04), lower fecal score (P = 0.02), and greater ether extract digestibility (P = 0.02) than the CON group. The ALF and OAH groups had lower concentrations of ruminal total volatile fatty acids (P = 0.01). Still, the ALF group had a greater proportion of acetate and a relative abundance of cellulose degradation-related bacteria (Lachnoclostridium_1 and Oribacterium) and a lower relative abundance of inflammation-related bacteria (Erysipelotrichaceae_UCG-009) in the rumen compared with CON. Interestingly, the average milk production from 6 to 200 d in milk (DIM) was greater in the ALF group (P < 0.01) even though no significant effects were found on the rumen fermentation parameters and blood metabolites at 200 DIM. Generally, alfalfa hay supplementation in preweaning dairy calves had positive effects in the short- and long-term in terms of rumen development, health status, and future milk production.
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BACKGROUND: Long intergenic non-coding RNA 00963 (LINC00963) is an oncogenic lncRNA in human cancers. However, little is known on how it impacts the pathogenesis of lung adenocarcinoma (LUAD). METHODS: Biological effects on proliferation, migration, invasion, and epithelial-mesenchymal transition (EMT) were examined by CCK-8, colony formation, EdU incorporation, transwell, and immunofluorescence assays, respectively. Macrophage polarization was evaluated by flow cytometry. Ubiquitination of Zeb1 was examined by co-immunoprecipitation. The location of LINC00963 in LUAD tissues and cell lines was tested by FISH assay. The LINC00963/HNRNPA2B1/Siah1 mRNA complex interaction was verified using RNA pull-down and immunoprecipitation assays. The exact roles of LINC00963 were further validated in metastasis and xenograft models. RESULTS: Higher LINC00963 expression in LUAD patients positively correlated with shorter overall survival, higher stages, and metastasis. LINC00963 mainly localized in the cytoplasm and aggravated malignant phenotypes of LUAD cells in vitro and metastasis in vivo. Mechanistically, LINC00963 directly interacted HNRNPA2B1 protein to trigger the degradation of Siah1 mRNA, which inhibited the ubiquitination and degradation of Zeb1. Moreover, exosomal LINC00963 derived from LUAD cells induced M2 macrophage polarization and promoted LUAD growth and metastasis. CONCLUSION: By stabilizing Zeb1 in cancer cells and delivering exosomes to induce M2 macrophage polarization, LINC00963 promoted the malignancy and metastasis of LUAD. Targeting LINC00963 may become a valuable therapeutic target for LUAD.
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Adenocarcinoma , Exossomos , Neoplasias Pulmonares , MicroRNAs , RNA Longo não Codificante , Humanos , MicroRNAs/genética , Neoplasias Pulmonares/metabolismo , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo , Exossomos/metabolismo , Linhagem Celular Tumoral , Proliferação de Células/genética , Pulmão/patologia , Adenocarcinoma/genética , RNA Mensageiro , Movimento Celular/genética , Regulação Neoplásica da Expressão Gênica , Homeobox 1 de Ligação a E-box em Dedo de Zinco/genética , Homeobox 1 de Ligação a E-box em Dedo de Zinco/metabolismoRESUMO
The terahertz (THz) band has a great potential for the development of communication technology, but it has not been fully utilized due to the lack of practical devices, especially actively controllable multifunctional devices. Here, we propose and demonstrate a Ge2Sb2Te5 (GST)-based metamaterial device, where an actively controllable function is experimentally verified by inducing the crystallization process with thermal activation. Cross-polarization conversion in the reflection mode and circular-to-linear polarization conversion in the transmission mode are obtained under crystalline and amorphous GST conditions, respectively. The combination of GST and THz waves has a wide range of applications and will further advance the THz field.
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Robotic platforms have been widely used in the various fields of clinical diagnosis and therapy of diseases in the past decade. Robotic-assisted bronchoscopy (RAB) demonstrates its advantages of visibility, flexibility, and stability in comparison to conventional bronchoscopic techniques. Improving diagnostic yield and navigation yield for peripheral pulmonary lesions has been defined; however, RAB platform of treatment was not reported. In this article, we report a case of a 52-year-old woman who was diagnosed with the tracheal adenoid cystic carcinoma and recurred in the second postoperative year, leading to the involvement of the entire tracheal wall and lumen obstruction. Since the lesion was inoperable, we combined RAB and photodynamic therapy (PDT) for the patient. The potential advantages of using RAB for PDT delivery include precise light irradiation of target lesions and stable intra-operative control over the long term. This is a novel application of RAB combined with PDT for airway diseases. The case report may provide a new insight into the diagnosis and treatment of pulmonary diseases. In addition to improving the diagnostic rates, the RAB platform may also play an important role in the treatment of airway and lung disease in the future.
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Carcinoma Adenoide Cístico , Pneumopatias , Fotoquimioterapia , Procedimentos Cirúrgicos Robóticos , Neoplasias da Traqueia , Feminino , Humanos , Pessoa de Meia-Idade , Traqueia/cirurgia , Traqueia/patologia , Broncoscopia/métodos , Carcinoma Adenoide Cístico/diagnóstico , Carcinoma Adenoide Cístico/tratamento farmacológico , Recidiva Local de Neoplasia/patologia , Neoplasias da Traqueia/diagnóstico , Neoplasias da Traqueia/tratamento farmacológico , Pneumopatias/patologiaRESUMO
Moiré configurations have recently attracted much attention due to their ability to enhance photonic responses and manipulate surface waves in the subwavelength ranges. However, previous studies have usually been focused on natural hyperbolic materials with limitations on patterning procedures, controlling rotation angles, and merely manipulating electric surface plasmons. Here, we theoretically and numerically investigate a novel magnetic moiré hyperbolic metasurface in the terahertz region, which enables two types of topological transition and a plethora of unusual magnetic moiré effects (magnetic surface wave manipulation, dispersion engineering, magic angles, spacer-dependent topological transition, and local field enhancement). This work extends twistronics and moiré physics to the terahertz region and magnetic polaritons, with potential applications in quantum physics, energy transfer, and planarized magnetic plasmonic devices.
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Various kinds of metasurfaces have been proposed because they can be tailored to achieve the desired modulations on electromagnetic wave that do not occur in nature. Compared to conventional metamaterials, coding metasurfaces integrated with information science theory possess numerous distinctive advantages - simple design, time-saving and compatibility with digital devices. Here we propose terahertz multifunctional anisotropic reflective metasurfaces with a metal-insulator-metal cavity structure whose top constructional layer consists of a pair of gold arc-rings and a gold cut-wire located between them. Two different functions of narrow-band absorption and broadband polarization conversion are realized based on different coding matrices using the binary codes '0' and '1'. Furthermore, we integrate a specific coding metasurface with vanadium dioxide (VO2) to realize a temperature-controlled active metasurface. Through the temperature change, dynamic functionalities switching between a narrow-band polarization converter with a polarization conversion ratio over 94% and an efficient low-pass filter are achieved under the phase transition of VO2, and the active metasurface is polarization independent. The proposed coding metasurfaces are verified numerically and experimentally, and have promising applications in terahertz modulation and functional devices.
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Inspired by the recent discovery of the Ti-doped BN nanocages, here we report the design of novel boron nitride (BN) nanoribbons (BNNRs) doped with fourth-row transition metals (Sc-Cu) and the prediction of their structural and electromagnetic properties. First-principles calculations and ab initio molecular dynamics simulations show that Ti-doped BNNR possesses both thermodynamic and kinetic stability at high temperatures for synthesis of BN materials. Metal doping may make the nonmagnetic pristine BNNR ferromagnetic or antiferromagnetic, depending on the metal. The doping with all considered metals reduces substantially the band gap of pristine BNNR. For example, Sc-doped BNNR is ferromagnetic with an indirect band gap of 1.18â eV, while V-doped nanoribbon is antiferromagnetic with a direct gap of 2.50â eV. Remarkably, the carrier mobility in both materials is significantly enhanced compared to the pristine BNNR. Our findings suggest that doping with different metals may endow BNNRs with versatile electronic and magnetic properties.
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In this study, benzocyclobutene-functionalized organic-inorganic hybrid spherical silicon nanoparticles (BCBNPs) with controllable size (200-600 nm) and good dispersion were synthesized by a one-step sol-gel method in aqueous solution. The effect of the reaction conditions (time, precursor concentration, pH value and temperature) on the particle size of the BCBNPs and the formation mechanism of the BCBNPs were studied. What is more, homogeneously dispersed BCBNPs/divinyltetramethyldisiloxane-bis(benzocyclobutene) (BCBNPs/PDVSBCB) nanocomposites were prepared and the influence of the incorporation of BCBNPs on the properties of the nanocomposites was investigated. The dielectric constants of the BCBNPs/PDVSBCB nanocomposites were drastically reduced relative to neat PDVSBCB, and were as low as 2.25 (30 MHz). Besides, the thermal and mechanical properties of the BCBNPs/PDVSBCB nanocomposites were significantly improved, evidencing their potential applications in the field of high-performance dielectric materials.
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With the rapid development of interregional power transmission, the redistribution of fossil and renewable energy resources has changed sharply, and its complexity poses a challenge to the evaluation of power carbon emission responsibility. This study constructs an interprovincial power transmission framework to measure the seasonal carbon emissions embodied in regional electricity consumption over the period of 2008-2015 based on quarterly data. Then, a structural decomposition approach was developed to identify the influential factors of carbon emissions embodied in provincial electricity consumption from a seasonal perspective. The results show that the assessment for embodied emissions of power consumption based on different levels of data may vary by as much as 20%, and the carbon emissions and carbon intensity of power consumption exhibit significant seasonal characteristics. Furthermore, it is revealed that the economic scale in the fourth quarter makes the most significant contribution to the emissions increment, especially in underdeveloped provinces, while the change in energy efficiency of power generation reduces more carbon emissions in the first and second quarters. In addition, the impact of the power transmission scale is more significant in the third and fourth quarters, and it has been close to or even more than the impact of traditional factors in some quarters. Finally, the impact of economic scale, power generation energy intensity, power generation mix and electricity utilization efficiency on the emissions of regional power grids shows a relatively stable increasing trend, but this trend of directional stability is not reflected in the effect of the power transmission structure and transmission scale. This study contributes to the identification of the impact of the power transmission structure and transmission scale. Moreover, this study highlights the importance of considering seasonal characteristics when estimating the carbon emissions of power consumption and formulating specific emission reduction policies. Additionally, it provides a more accurate evaluation of carbon emissions and proposes several prominent recommendations for policy makers.
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Dióxido de Carbono , Eletricidade , Dióxido de Carbono/análise , Estações do Ano , Energia Renovável , China , Desenvolvimento EconômicoRESUMO
Originating from the study of topological photonic crystals (TPCs), analogues of the quantum spin Hall effect have been used as a potential way to control the propagation of electromagnetic waves. Due to the topological robustness of the spin TPCs, the edge states along the interface between the trivial and topological areas are topologically protected and not reflected from structural defects and disorders. Here, on the basis of the time-spatial reversal symmetry and topological defect theory, we demonstrate broadening of the edge state bandwidth in spin TPCs made of regular metallic cross structures by simultaneously deforming the hexagonal honeycomb lattice and adjusting the rotation angle. Due to the simultaneous tuning of the two parameters, the designed spin TPCs possess more flexibility. Topologically protected one-way propagating edge states are observed in the terahertz regime, where electromagnetic waves propagate along sharp corners without backscattering. Our findings offer the potential application for topological devices in terahertz technology and are beneficial for the development of 6G mobile communications.
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Active control of metasurfaces has attracted widespread attention because of the adjustable electromagnetic properties obtained. Here we designed and experimentally studied a dynamically controllable polarization converter in the terahertz band. By designing the structural parameters and utilizing the insulator-to-metal phase transition of vanadium dioxide and principle of current resonance, dynamic tunability of the polarization conversion function from dual-broadband (0.45â¼0.77 THz and 0.97â¼1.2 THz) to ultra-broadband (0.38â¼1.20 THz) can be realized with a high polarization conversion ratio. The scheme proposed here can find potential applications in integrated terahertz systems, sensing, imaging and communications areas.
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Piezoelectric materials are technologically important, and the most used are perovskite ferroelectrics. In recent years, more and more emerging areas have put forward new requirements for piezoelectric materials, such as light weight, low acoustic impedance, good flexibility, and biocompatibility. In this context, hybrid organic-inorganic perovskite ferroelectrics have emerged as promising supplements, because they combine attractive features of inorganic and organic materials. Among them, hybrid double-metal perovskites have recently been found to exhibit excellent ferroelectricity. However, their potential as piezoelectric materials has not been exploited. Here, we describe large piezoelectric response in hybrid rare-earth double perovskite relaxor ferroelectrics (RM3HQ)2RbLa(NO3)6 and (RM3HQ)2NH4La(NO3)6 (RM3HQ = R-N-methyl-3-hydroxylquinuclidinium). They are simultaneously ferroelectric and ferroelastic crystals, with the R3 ferroelectric phase and P213 paraelectric phase. We found that ferroelectric polar microdomains and paraelectric nonpolar regions coexist in a wide temperature range through variable-temperature piezoresponse force microscopy images. The two-phase coexistence reveals low energy barriers of transitions between the two phases and between the polar microdomains with different polarization directions. These lead to the easy polarization rotation of the polar microdomains upon applying a stress and, accordingly, the large piezoelectric response up to 106 pC N-1 for (RM3HQ)2RbLa(NO3)6. This finding represents a significant step toward novel applications of piezoelectric materials based on lead-free hybrid perovskites.
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As a major branch of hybrid perovskites, two-dimensional (2D) hybrid double perovskites are expected to be ideal systems for exploring novel ferroelectric properties, because they can accommodate a variety of organic cations and allow diverse combinations of different metal elements. However, no 2D hybrid double perovskite ferroelectric has been reported since the discovery of halide double perovskites in the 1930s. Based on trivalent rare-earth ions and chiral organic cations, we have designed a new family of 2D rare-earth double perovskite ferroelectrics, A4MIMIII(NO3)8, where A is the organic cation, MI is the alkaline metal or ammonium ion, and MIII is the rare-earth ion. This is the first time that ferroelectricity is realized in 2D hybrid double perovskite systems. These ferroelectrics have achieved high-temperature ferroelectricity and photoluminescent properties. By varying the rare-earth ion, variable photoluminescent properties can be achieved. The results reveal that the 2D rare-earth double perovskite systems provide a promising platform for achieving multifunctional ferroelectricity.
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In this paper, pure silk protein was extracted from Bombyx mori silks and fabricated into a new kind of disordered bio-microfiber structure using electrospinning technology. Coherent random lasing emission with low threshold was achieved in the silk fibroin fibers. The random lasing emission wavelength can be tuned in the range of 33 nm by controlling the pump location with different scattering strengths. Therefore, the bio-microfiber random lasers can be a wide spectral light source when the system is doped with a gain or energy transfer medium with a large fluorescence emission band. Application of the random lasers of the bio-microfibers as a low-coherence light source in speckle-free imaging had also been studied.
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Fibroínas/química , Lasers , Luz , Animais , Bombyx , Fibroínas/ultraestrutura , Processamento de Imagem Assistida por Computador , Dispositivos ÓpticosRESUMO
Substitution of A-site and/or X-site ions of ABX3 -type perovskites with organic groups can give rise to hybrid perovskites, many of which display intriguing properties beyond their parent compounds. However, this method cannot be extended effectively to hybrid antiperovskites. Now, the design of hybrid antiperovskites under the guidance of the concept of Goldschmidt's tolerance factor is presented. Spherical anions were chosen for the A and B sites and spherical organic cations for the X site, and seven hybrid antiperovskites were obtained, including (F3 (H2 O)x )(AlF6 )(H2 dabco)3 , ((Co(CN)6 )(H2 O)5 )(MF6 )(H2 dabco)3 (M=Al3+ , Cr3+ , or In3+ ), (Co(CN)6 )(MF6 )(H2 pip)3 (M=Al3+ or Cr3+ ), and (SbI6 )(AlF6 )(H2 dabco)3 . These new structures reveal that all ions at A, B, and X sites of inorganic antiperovskites can be replaced by molecular ions to form hybrid antiperovskites. This work will lead to the synthesis of a large family of hybrid antiperovskites.
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The information-carrying capacity of a memory is known to be a thermodynamic resource facilitating the conversion of heat to work. Szilard's engine explicates this connection through a toy example involving an energy-degenerate two-state memory. We devise a formalism to quantify the thermodynamic value of memory in general quantum systems with nontrivial energy landscapes. Calling this the thermal information capacity, we show that it converges to the nonequilibrium Helmholtz free energy in the thermodynamic limit. We compute the capacity exactly for a general two-state (qubit) memory away from the thermodynamic limit, and find it to be distinct from known free energies. We outline an explicit memory-bath coupling that can approximate the optimal qubit thermal information capacity arbitrarily well.
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This study experimentally reveals the self-biasing phenomenon in prism laser gyros. When the gyro operates in a specific double longitudinal mode and four-frequency oscillation state, the gyro can detect the normal angular velocity component of the Earth's rotation without dithering, the self-biasing status is induced. In this study, a laboratory platform of the self-biasing laser gyro is established. The two longitudinal modes oscillate on both sides of the gain curve. The intensity ratio of the strong and weak modes is about 1.4 to 1, and the coupling effects of these two modes with parallel linear polarization have been discussed using Lamb theory. Because the adverse effects of biasing technical are avoided, the self-biasing gyro has potential to challenge the strategic precision.
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Quantum resource theories seek to quantify sources of nonclassicality that bestow quantum technologies their operational advantage. Chief among these are studies of quantum correlations and quantum coherence. The former isolates nonclassicality in the correlations between systems, and the latter captures nonclassicality of quantum superpositions within a single physical system. Here, we present a scheme that cyclically interconverts between these resources without loss. The first stage converts coherence present in an input system into correlations with an ancilla. The second stage harnesses these correlations to restore coherence on the input system by measurement of the ancilla. We experimentally demonstrate this interconversion process using linear optics. Our experiment highlights the connection between nonclassicality of correlations and nonclassicality within local quantum systems and provides potential flexibilities in exploiting one resource to perform tasks normally associated with the other.