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The spin-Seebeck effect together with a high spin thermoelectric conversion efficiency has been regarded as one of the core topics in spin caloritronics. In this work, we propose a spin caloritronic device constructed on hydrogen-terminated sawtooth graphene-like nanoribbons periodically embedded with four- and eight-membered rings to investigate the thermal spin currents and thermoelectric properties by using density functional theory combined with the non-equilibrium Green's function method. Our theoretical results show that spin-Seebeck currents are induced by the temperature gradient between two leads due to two isolated spin-up and spin-down transport channels above or below the Fermi level. Besides, the embedded four- and eight-membered rings break the mirror symmetry of graphene-like nanoribbons and increase the phonon scattering to lower the lattice conductivity, contributing to the enhancement of the spin figure of merit. Moreover, the increasing width of the nanoribbons can effectively enhance the spin-Seebeck currents and reduce their threshold temperatures to improve the device performances. These systematic investigations not only give us an in-depth understanding into the realistic spin caloritronic device applications of graphene-like nanoribbons, but also help us to choose feasible routes to improve the spin-Seebeck effect with a high spin figure of merit in nanostructures.
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Ruxolitinib {RUX; systematic name: (3R)-3-cyclopentyl-3-[4-(7H-pyrrolo[2,3-d]pyrimidin-4-yl)-1H-pyrazol-1-yl]propanenitrile, C17H18N6} is an orally bioavailable JAK1/2 inhibitor approved for treating intermediate- or high-risk myelofibrosis (MF) and high-risk polycythemia vera (PV). Recent patents claim that RUX can exist in many different forms, information for which is important for the clinical utilization of RUX, especially for the formulation and bioavailability of the drug. But there has been no detailed study on its forms so far. Herein crystals of RUX and its dihydrate (RUX-2H; C17H18N6·2H2O) and phosphate (RUX-P; systematic name: 4-{1-[(1R)-2-cyano-1-cyclopentylethyl]-1H-pyrazol-4-yl}-7H-pyrrolo[2,3-d]pyrimidin-3-ium dihydrogen phosphate, C17H19N6+·H2PO4-) were prepared successfully and their structures studied in detail for the first time. Our study shows that the three crystals of RUX differ in the orientation of the pyrimidine ring relative to the pyrazole ring of the RUX molecule, and in their hydrogen-bond interactions. The water molecules in RUX-2H and the dihydrogen phosphate anion in RUX-P enrich the hydrogen-bond networks in these forms. The expected proton transfer occurs in RUX phosphate and the protonated N atom is engaged in a charge-assisted hydrogen bond with the counter-anion. Hydrogen-bonding interactions dominate in the crystal packing of the three forms. The detailed conformations and packing of the three forms were compared through the calculation of both Hirshfeld surfaces and fingerprint plots.
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Ligação de Hidrogênio , Janus Quinase 1 , Janus Quinase 2 , Nitrilas , Fosfatos , Pirazóis , Pirimidinas , Pirimidinas/química , Pirimidinas/farmacologia , Pirazóis/química , Pirazóis/farmacologia , Nitrilas/química , Cristalografia por Raios X , Janus Quinase 2/antagonistas & inibidores , Janus Quinase 2/química , Janus Quinase 2/metabolismo , Fosfatos/química , Janus Quinase 1/antagonistas & inibidores , Janus Quinase 1/química , Estrutura Molecular , Inibidores de Proteínas Quinases/química , Inibidores de Proteínas Quinases/farmacologia , HumanosRESUMO
Background: Löffler's endocarditis (LE) is a frequently encountered condition in hypereosinophilic syndrome and is associated with a significant morbidity and mortality rate. Case Summary: A 22-year-old man presented with acute dyspnoea, recurring wheezing, and cough, leading to his hospital admission. Multimodal diagnostic imaging revealed a manifestation of eosinophil-mediated cardiac injury in the thrombus formation stage. Moreover, a mural thrombus and thickened endocardium had caused severe obstruction of the right ventricular outflow tract (RVOT) and complete obliteration of the right ventricular apex, resulting in a significant reduction in right ventricular cardiac output. The patient received a diagnosis of LE and was treated with high-dose corticosteroids and anticoagulants. To alleviate the RVOT obstruction, an emergency surgical intervention was conducted through median sternotomy to the removal of the mural thrombus and resection of the thickened endocardium. Subsequently, eosinophil counts normalized within 1 month. Follow-up imaging examination demonstrated the existence of a residual section of thickened endocardium within the right ventricular free wall. Importantly, no mural thrombus was detected with complete relief of the RVOT obstruction. Notably, a transthoracic echocardiography examination at the 3-month postoperative unveiled a significant regression in right ventricular endomyocardial fibrosis. The patient's condition exhibited tangible improvement, with no adverse events observed. Discussion: Multimodal imaging is essential for the early diagnosis and accurate staging of LE. Timely surgical intervention, combined with corticosteroid therapy, is an effective therapeutic approach in selected patients with LE. This approach is crucial to achieve remission of acute phase symptoms and improve prognosis.
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Electrolyte engineering plays a crucial role in enhancing the performance of lithium metal batteries (LMBs) featuring high-voltage cathodes and limited lithium anodes, thereby unlocking their potential for high-energy electrochemical storage. Herein, an entropy-driven hybrid gel electrolyte with enhanced diversity in Li-ion solvation structures is designed by incorporating substantial amounts of insoluble LiPO2F2 and LiNO3 salts into LiPF6-based carbonate electrolytes, followed by in situ thermal polymerization. Specifically, the Li+ solvation structures are modulated via ionophilic NO3- and PO2F2- to generate an anion-rich solvation sheath and thus promote anion reduction at the electrode-electrolyte interface. The interfaces enriched in anion-derived inorganic components facilitate rapid ionic transport, thus enabling smooth and dense Li morphology and ultimately enhancing the electrochemical performance of LMBs. As a result, this high-hybrid gel electrolyte confers LMBs employing high-voltage NCM cathodes, as demonstrated by sustained performance in both coin-cell (500 cycles at 4.5 V) and Ah-level pouch cell configurations under practical conditions (60 cycles, N/P: 1.92, and E/C: 2.0 g Ah -1).
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Amino acid-derived quaternary ammonium salts were successfully applied in the asymmetric aza-Henry reaction of nitromethane to N-Boc trifluoromethyl ketimines. α-Trifluoromethyl ß-nitroamines were synthesized in good to excellent yields with moderate to good enantioselectivities. This reaction is distinguished by its mild conditions, low catalyst loading (1 mol%), and catalytic base. It also proceeded on a gram scale without loss of enantioselectivity. The products were transformed to a series of adamantane-type compounds containing chiral trifluoromethylamine fragments. The potent anticancer activities of these compounds against liver cancer HepG2 and melanoma B16F10 were evaluated. Six promising compounds with notable efficacy have potential for further development.
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Achieving a highly robust zinc (Zn) metal anode is extremely important for improving the performance of aqueous Zn-ion batteries (AZIBs) for advancing "carbon neutrality" society, which is hampered by the uncontrollable growth of Zn dendrite and severe side reactions including hydrogen evolution reaction, corrosion, and passivation, etc. Herein, an interlayer containing fluorinated zincophilic covalent organic framework with sulfonic acid groups (COF-S-F) is developed on Zn metal (Zn@COF-S-F) as the artificial solid electrolyte interface (SEI). Sulfonic acid group (- SO3H) in COF-S-F can effectively ameliorate the desolvation process of hydrated Zn ions, and the three-dimensional channel with fluoride group (-F) can provide interconnected channels for the favorable transport of Zn ions with ion-confinement effects, endowing Zn@COF-S-F with dendrite-free morphology and suppressed side reactions. Consequently, Zn@COF-S-F symmetric cell can stably cycle for 1,000 h with low average hysteresis voltage (50.5 mV) at the current density of 1.5 mA cm-2. Zn@COF-S-F|MnO2 cell delivers the discharge specific capacity of 206.8 mAh g-1 at the current density of 1.2 A g-1 after 800 cycles with high-capacity retention (87.9%). Enlightening, building artificial SEI on metallic Zn surface with targeted design has been proved as the effective strategy to foster the practical application of high-performance AZIBs.
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Aqueous zinc ion batteries (AZIBs) have attracted much attention for their safety, low cost and high theoretical capacity. Nevertheless, Zn dendrites and the adverse reactions such as corrosion, hydrogen evolution and passivation on the anode affect the cycle life and stability of AZIBs. Herein, superabsorbent starch (SS) was employed on Zn foil to form an artificial interface protection layer, which inhibited the formation of dendrites by guiding the uniform deposition of Zn2+. SS with a large amount of oxygen-containing functional group is superabsorbent, which can attract the active water around the hydrated Zn2+, promoting the desolvation process of the hydrated Zn2+ and significantly inhibiting the occurrence of hydrogen evolution reaction. In addition, the inherent pore structure of the SS artificial interfacial layer can induce uniform nucleation of Zn2+ and inhibit the dendrites growth. Moreover, compared to bare Zn//MnO2 cell (44.1 %), the capacity retention of Zn@SS//MnO2 cell remained as high as 87.8 % after 1000 cycles at 1.5 A g-1. The simple method provided a new method for the rapid development of AZIBs.
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Local authorities worldwide are actively encouraging waste material trading within their jurisdictions as a promising strategy to develop a more circular economy. Construction activities consume natural resources intensively and generate massive solid waste. With proper ex-post treatment, the waste materials can be recycled or even directly reused, hence contributing to the circular economy. Using the Hong Kong-Macao-Guangdong Greater Bay Area (GBA) as the context, we simulate the impacts of a construction waste trading market on the waste flows and the resulting monetary exchanges. Our model views each city as a representative agent that maximizes the benefit of conducting waste recycling. The interactions of their profit-seeking behavior will lead to optimized overall social costs. We then solve this problem using a non-linear optimization algorithm. The simulation shows that with a fully operational market, the traded waste materials amount to 1253.84 million m3, covering 82.36% of GBA's total construction waste generation in a typical year. The monetary transactions equal to US$38.41 billion. Such huge payments present a great opportunity for the GBA cities to develop their recycling industries. In addition, we argue that although increasing public pressure is effective in reducing inequalities in the final waste distribution, it also results in fewer financial transactions flowing to less-developed cities, which reduces their funding for developing the circular economy.
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Indústria da Construção , Gerenciamento de Resíduos , China , Hong Kong , Macau , Cidades , Reciclagem , Materiais de ConstruçãoRESUMO
The deep mining of coal mines in North China faces the serious threat of water inrush from karst aquifers in the coal seam floors, and regional advance grouting technology (RAGT) is an effective means to prevent and control such disasters. However, it is difficult to choose the grouting pressure during the implementation of RAGT, and excessive grouting pressure will lead to the splitting of karst fracture and reduce the grouting effect. In this study, based on the Bernoulli equation, the relationship between the ground grouting pressure and critical grouting pressure during grouting is established. Based on the Hoek-Brown (H-B) strength criterion and a fracture mechanics analysis of hydraulic fracturing, a theoretical equation of the critical grouting pressure for fracture splitting during grouting is obtained. The determination methods of the main parameters, such as the length of the fracture, internal friction angle, and H-B constant of the intact rock and geological strength index, and their effects on the critical grouting pressure, are discussed. The results show that the joint influence of the H-B constant and geological strength index of the intact rock is the key factor influencing the critical grouting pressure. The theoretical research results are applied to the Xujiazhuang limestone grouting reinforcement project of the floor of coal seam 11 in the Zhaoguan coal mine. The critical grouting pressure of the aquifer is determined to be 14.54 MPa, which guides the smooth implementation of the project.
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Comparing with the enduring efforts to reduce carbon emissions in design, construction, and operation stages of a construction project, less attention has been paid to emission abatement potential in the end-of-life stage, particularly by recycling waste generated by construction and demolition (C&D) activities. This research aims to cover this knowledge void by quantifying the embodied carbon saving potential of recycling C&D waste. It does so by adopting a Life Cycle Assessment (LCA) and choosing the Guangdong-Hong Kong-Macao Greater Bay Area (GBA) in South China for a case study. The carbon emission is treated as embodied in construction materials, by recycling which the equivalent amount of carbon generated from the virgin materials can be saved. It is estimated that the GBA produced 128.49 Mt. of C&D waste in 2018, which implies an embodied carbon saving potential of 92.26 Mt. carbon emissions. The research goes further to understand the future C&D waste generation and their corresponding embodied carbon saving potential. A first-of-its-kind dynamic approach is developed to simulate the future 42-year saving potential under four construction development scenarios. Depending on different construction growth rates, the embodied carbon saving potential in 2060 can be up to 894.80 Mt. and down to 166.34 Mt. This research can help achieve China's 2060 carbon neutral goal by focusing on a non-negligible sector in an economically important region. Methods proposed in this paper are also applicable to other regions worldwide, especially where C&D waste data is insufficient.
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Indústria da Construção , Gerenciamento de Resíduos , Carbono , China , Materiais de Construção , Resíduos Industriais/análise , ReciclagemRESUMO
OBJECTIVE: To investigate the expression of transient receptor potential (TRP) superfamily genes, especially TRPC7-AS1 in hepatitis B virus- (HBV-) related hepatocellular carcinoma (HCC). METHODS: Three cancer samples of HBV-related HCC at phase IV and matched paracancerous liver tissues were included in the study. Total RNA was extracted, and differential expression of RNA was screened by high-throughput transcriptome sequencing. The expression of TRPC7-AS1 was detected by quantitative real-time PCR. The N6-adenosyl methylation RNA in MHCC97H, HepG2, and HL-7702 was enriched by coimmunoprecipitation with m6A antibody, and the relative level of N6-adenosyl methylation RNA in TRPC7-AS1 was detected. RESULTS: The expression of TRP family genes in cancer tissues was higher than that in paracancerous liver tissues, including TRPC7-AS1, TRPC4AP, PKD1P6, and PKD1P1. Moreover, the expression level of TRPC7-AS1 in MHCC97H and HepG2 was also significantly higher than that in L02, a normal liver cell. The methylation level of N6-adenosine of TRPC7-AS1 was lower in HepG2 cells than that in L02 cells. CONCLUSION: TRP superfamily genes, especially TRPC7-AS1, were highly expressed in HBV-related HCC. TRPC7-AS1 could be a potential therapeutic target or diagnostic marker for HCC.
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Subject to the complex hydrogeological environment where underground engineering is located, the grouting prevention and control of microfissure water ingress are increasingly strict. Silica sol grout has been increasingly used in field tests because of its fine particles and good injectability. Therefore, it is necessary to examine the time-dependent viscosity of silica sol grout and clarify its diffusion law in a rock fissure. In this study, the time dependence of the viscosity of silica sol grout was studied, and then the grout viscosity was subdivided into a slow growth period, accelerated growth period, and rapid curing period according to the growth rate. The effects of the concentration of colloidal silica suspension, the concentration of accelerant, and the mixing volume ratio of the two on the growth of the slurry viscosity were studied. A parameter λ was introduced to comprehensively characterize the influence of the three factors on the rheological properties of the slurry. The relationship between the gel induction time and λ and the accelerating growth stage of the slurry gel was obtained by data fitting. The time-dependent equation of the silica sol solution was established. The difference in the grouting diffusion law between silica sol grout and cement-sodium silicate grout (C-S grout) is compared and analyzed by a stepwise calculation method under two grouting modes (constant-pressure grouting and constant-rate grouting). The results show that under the condition of constant-pressure grouting, the silica sol grout migrates and diffuses continuously for a long time, while the C-S grout is close to the final diffusion form at 15-20 s, and the maximum diffusion distance is much smaller than that of silica sol grout. Under the condition of constant-rate grouting, the grouting pressure driving C-S grout increases sharply with time. Compared with C-S grout, silica sol grout has the obvious advantages of a longer effective diffusion time and lower energy consumption. The research results have certain theoretical significance and reference value for the engineering design of silica sol grouting.