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1.
Phys Rev Lett ; 133(16): 166301, 2024 Oct 18.
Artículo en Inglés | MEDLINE | ID: mdl-39485961

RESUMEN

The Hall effect of topological quantum materials often reveals essential new physics and possesses potential for application. The magnetic Weyl semimetal is one especially interesting example that hosts an interplay between the spontaneous time-reversal symmetry-breaking topology and the external magnetic field. However, it is less known beyond the anomalous Hall effect thereof, which is unable to account for plenty of magnetotransport measurements. We propose a new Hall effect characteristically nonmonotonic with respect to the external field, intrinsic to the three-dimensional Weyl topology, and free from chemical potential fine-tuning. Two related mechanisms from the Landau level bending and chiral Landau level shifting are found, together with their relation to the Shubnikov-de Hass effect. This field-dependent Hall response, universal to thin films and bulk samples, provides a concrete physical picture for existing measurements and is promising to guide future experiments.

3.
Zhongguo Zhong Yao Za Zhi ; 49(14): 3971-3976, 2024 Jul.
Artículo en Chino | MEDLINE | ID: mdl-39099370

RESUMEN

The development of traditional Chinese medicine(TCM) preparations as an incubator for new drugs in medical institutions has flourished, while an evaluation index system remains to be established for comprehensively assessing the development value of these prescriptions. This study established an item pool through literature research, employed the Delphi method to determine the content of evaluation indexes, and adopted the superiority chart to determine the weight of each index. Two-level evaluation index system for the development value of TCM preparations in medical institutions was established, which included 7 first-level items and 36 se-cond-level items, demonstrating scientific validity. The first-level items(weight) were inheritance(10.61%), effectiveness(23.22%), safety(22.71%), innovation(13.21%), economy(10.00%), suitability(8.57%), and accessibility(11.68%). The top three second-level items in terms of weight distribution were adverse reaction monitoring(6.73%), evidence of therapeutic effect(5.71%), and clinical response rate(4.75%). The bottom three second-level items were production advantages(0.86%), medicinal dosage(0.48%), and medicinal smell or taste(0.18%). The content validity of the established system was assessed, which revealed that the index system was reliable, with the overall and average content validity indexes of 0.47 and 0.90, respectively. Furthermore, the established evaluation index system was used to evaluate six TCM preparations in a city-level hospital of TCM in Sichuan Province, which demonstrated that the system had operability. The results indicate that the evaluation index system is scientific, reliable, and operable, providing a reference for developers to selectively develop TCM preparations in medical institutions. In practical application, the system can be adjusted regarding the index weights according to actual conditions.


Asunto(s)
Medicamentos Herbarios Chinos , Medicina Tradicional China , Medicina Tradicional China/normas , Medicamentos Herbarios Chinos/normas , Medicamentos Herbarios Chinos/análisis , Medicamentos Herbarios Chinos/química , Humanos
4.
Nat Commun ; 15(1): 6799, 2024 Aug 09.
Artículo en Inglés | MEDLINE | ID: mdl-39122744

RESUMEN

Spin-polarized light-emitting diodes (spin-LEDs) convert the electronic spin information to photon circular polarization, offering potential applications including spin amplification, optical communications, and advanced imaging. The conventional control of the emitted light's circular polarization requires a change in the external magnetic field, limiting the operation conditions of spin-LEDs. Here, we demonstrate an atomically thin spin-LED device based on a heterostructure of a monolayer WSe2 and a few-layer antiferromagnetic CrI3, separated by a thin hBN tunneling barrier. The CrI3 and hBN layers polarize the spin of the injected carriers into the WSe2. With the valley optical selection rule in the monolayer WSe2, the electroluminescence exhibits a high degree of circular polarization that follows the CrI3 magnetic states. Importantly, we show an efficient electrical tuning, including a sign reversal, of the electroluminescent circular polarization by applying an electrostatic field due to the electrical tunability of the few-layer CrI3 magnetization. Our results establish a platform to achieve on-demand operation of nanoscale spin-LED and electrical control of helicity for device applications.

5.
Sci Adv ; 10(32): eadn5696, 2024 Aug 09.
Artículo en Inglés | MEDLINE | ID: mdl-39121229

RESUMEN

The indirect exchange interaction between local magnetic moments via surface electrons has been long predicted to bolster the surface ferromagnetism in magnetic topological insulators (MTIs), which facilitates the quantum anomalous Hall effect. This unconventional effect is critical to determining the operating temperatures of future topotronic devices. However, the experimental confirmation of this mechanism remains elusive, especially in intrinsic MTIs. Here, we combine time-resolved photoemission spectroscopy with time-resolved magneto-optical Kerr effect measurements to elucidate the unique electromagnetism at the surface of an intrinsic MTI MnBi2Te4. Theoretical modeling based on 2D Ruderman-Kittel-Kasuya-Yosida interactions captures the initial quenching of a surface-rooted exchange gap within a factor of two but overestimates the bulk demagnetization by one order of magnitude. This mechanism directly explains the sizable gap in the quasi-2D electronic state and the nonzero residual magnetization in even-layer MnBi2Te4. Furthermore, it leads to efficient light-induced demagnetization comparable to state-of-the-art magnetophotonic crystals, promising an effective manipulation of magnetism and topological orders for future topotronics.

6.
J Obstet Gynaecol ; 44(1): 2390564, 2024 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-39150330

RESUMEN

BACKGROUND: This meta-analysis seeks to assess the efficacy and safety of pembrolizumab in individuals with advanced or recurrent cervical cancer. METHODS: Databases from PubMed, Embase, and the Cochrane Library were all thoroughly searched for pertinent research. Outcomes include complete response (CR), partial response (PR), stable disease (SD), disease progression (PD), overall response rate (ORR), disease control rate (DCR), median progression-free survival (mPFS), median overall survival (mOS), and adverse events (AEs) were retrieved for further analysis. RESULTS: Ten trials with 721 patients were included in this meta-analysis. The pooled results for patients with cervical cancer receiving pembrolizumab were as follows: CR (0.06, 95%CI: 0.02-0.10), PR (0.15, 95%CI: 0.08-0.22), SD (0.16, 95%CI: 0.13-0.20), PD (0.50, 95%CI: 0.25-0.75), ORR (0.26, 95%CI: 0.11-0.41) and DCR (0.42, 95%CI: 0.13-0.71), respectively. Regarding survival analysis, the pooled mPFS and mOS were 3.81 and 10.15 months. Subgroup analysis showed that pembrolizumab in combination was more beneficial in CR (0.16 vs. 0.03, p = 0.012), PR (0.24 vs. 0.08, p = 0.032), SD (0.11 vs. 0.19, p = 0.043), ORR (0.42 vs. 0.11, p = 0.014), and mPFS (5.54 months vs. 2.27 months, p < 0.001) than as single agent. The three most common AEs were diarrhoea (0.25), anaemia (0.25), and nausea (0.21), and the incidence of grade 3-5 AEs was significantly lower, rarely surpassing 0.10. CONCLUSIONS: For patients with advanced or recurrent cervical cancer, this systematic review and meta-analysis demonstrated that pembrolizumab had a favourable efficacy and tolerability. Future research will primarily focus on optimising customised regiments that optimally integrate pembrolizumab into new therapies and combination strategies. Designed to maximise patient benefit and efficiently control adverse effects while maintaining a high standard of living.


This study demonstrated the efficacy and safety of pembrolizumab in individuals with advanced or recurrent cervical cancer. The study found that an upfront combination of chemotherapy and pembrolizumab immunotherapy appears to be a compelling strategy for these patients. More large-scale and multicentre randomised controlled trials will be required in the future to validate the precise benefits of pembrolizumab in new therapies and combination strategies for the treatment of cervical cancer.


Asunto(s)
Anticuerpos Monoclonales Humanizados , Antineoplásicos Inmunológicos , Recurrencia Local de Neoplasia , Neoplasias del Cuello Uterino , Humanos , Neoplasias del Cuello Uterino/tratamiento farmacológico , Neoplasias del Cuello Uterino/mortalidad , Anticuerpos Monoclonales Humanizados/uso terapéutico , Anticuerpos Monoclonales Humanizados/efectos adversos , Femenino , Recurrencia Local de Neoplasia/tratamiento farmacológico , Antineoplásicos Inmunológicos/efectos adversos , Antineoplásicos Inmunológicos/uso terapéutico , Resultado del Tratamiento , Supervivencia sin Progresión , Persona de Mediana Edad
7.
Zhongguo Zhong Yao Za Zhi ; 49(11): 2841-2852, 2024 Jun.
Artículo en Chino | MEDLINE | ID: mdl-39041143

RESUMEN

The discipline development is the pillar for the development of traditional Chinese medicine( TCM). The academic progress in TCM is the commanding height of the discipline development of TCM. To lead and promote the development and academic progress of TCM, the China Association of Chinese Medicine has summarized the Top Ten Academic Achievements in Traditional Chinese Medicine during 2020-2022, the Major Scientific Problems, Engineering Technical Problems, and Industrial Technical Problems in Traditional Chinese Medicine during 2019-2023, and the Remarkable Research Achievements of Traditional Chinese Medicine during 2012-2022. Based on the above research reports and the research achievements awarded the national science and technology prizes in TCM in the last 20 years and according to the current situation and layout of TCM discipline development, this paper reviews the major research achievements of TCM in the last two decades and the latest research progress in TCM during 2020-2023. The major scientific, engineering technical, and industrial technical problems in TCM are analyzed and the emerging trends of TCM are prospected in accordance with the development laws and characteristics of TCM. This review provides new ideas and reference for the high-quality development of TCM in the new era.


Asunto(s)
Medicina Tradicional China , Medicina Tradicional China/tendencias , China , Humanos , Medicamentos Herbarios Chinos
9.
Pestic Biochem Physiol ; 201: 105883, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38685249

RESUMEN

Trypsin is one of the most diverse and widely studied protease hydrolases. However, the diversity and characteristics of the Trypsin superfamily of genes have not been well understood, and their role in insecticide resistance is yet to be investigated. In this study, a total of 342 Trypsin genes were identified and classified into seven families based on homology, characteristic domains and phylogenetics in Anopheles sinensis, and the LY-Domain and CLECT-Domain families are specific to the species. Four Trypsin genes, (Astry2b, Astry43a, Astry90, Astry113c) were identified to be associated with pyrethroid resistance based on transcriptome analyses of three field resistant populations and qRT-PCR validation, and the knock-down of these genes significantly decrease the pyrethroid resistance of Anopheles sinensis based on RNAi. The activity of Astry43a can be reduced by five selected insecticides (indoxacarb, DDT, temephos, imidacloprid and deltamethrin); and however, the Astry43a could not directly metabolize these five insecticides, like the trypsin NYD-Tr did in earlier reports. This study provides the overall information frame of Trypsin genes, and proposes the role of Trypsin genes to insecticide resistance. Further researches are necessary to investigate the metabolism function of these trypsins to insecticides.


Asunto(s)
Anopheles , Resistencia a los Insecticidas , Insecticidas , Piretrinas , Tripsina , Animales , Anopheles/genética , Anopheles/efectos de los fármacos , Resistencia a los Insecticidas/genética , Insecticidas/farmacología , Tripsina/genética , Tripsina/metabolismo , Piretrinas/farmacología , Filogenia , Mosquitos Vectores/genética , Mosquitos Vectores/efectos de los fármacos , Malaria/transmisión , Proteínas de Insectos/genética , Proteínas de Insectos/metabolismo
10.
Proc Natl Acad Sci U S A ; 121(13): e2313488121, 2024 Mar 26.
Artículo en Inglés | MEDLINE | ID: mdl-38513104

RESUMEN

Weyl semimetal showing open-arc surface states is a prominent example of topological quantum matter in three dimensions. With the bulk-boundary correspondence present, nontrivial surface-bulk hybridization is inevitable but less understood. Spectroscopies have been often limited to verifying the existence of surface Fermi arcs, whereas its spectral shape related to the hybridization profile in energy-momentum space is not well studied. We present an exactly solvable formalism at the surface for a wide range of prototypical Weyl semimetals. The resonant surface state and the bulk influence coexist as a surface-bulk hybrid and are treated in a unified manner. Directly accessible to angle-resolved photoemission spectroscopy, we analytically reveal universal information about the system obtained from the spectroscopy of resonant topological states. We systematically find inhomogeneous and anisotropic singular responses around the surface-bulk merging borderline crossing Weyl points, highlighting its critical role in the Weyl topology. The response in scanning tunneling spectroscopy is also discussed. The results will provide much-needed insight into the surface-bulk-coupled physical properties and guide in-depth spectroscopic investigation of the nontrivial hybrid in many topological semimetal materials.

11.
Sci Bull (Beijing) ; 69(3): 325-333, 2024 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-38129237

RESUMEN

Non-Hermitian systems have been discussed mostly in the context of open systems and nonequilibrium. Recent experimental progress is much from optical, cold-atomic, and classical platforms due to the vast tunability and clear identification of observables. However, their counterpart in solid-state electronic systems in equilibrium remains unmasked although highly desired, where a variety of materials are available, calculations are solidly founded, and accurate spectroscopic techniques can be applied. We demonstrate that, in the surface state of a topological insulator with spin-dependent relaxation due to magnetic impurities, highly nontrivial topological soliton spin textures appear in momentum space. Such spin-channel phenomena are delicately related to the type of non-Hermiticity and correctly reveal the most robust non-Hermitian features detectable spectroscopically. Moreover, the distinct topological soliton objects can be deformed to each other, mediated by topological transitions driven by tuning across a critical direction of doped magnetism. These results not only open a solid-state avenue to exotic spin patterns via spin- and angle-resolved photoemission spectroscopy, but also inspire non-Hermitian dissipation engineering of spins in solids.

12.
Zool Res ; 44(6): 1064-1079, 2023 Nov 18.
Artículo en Inglés | MEDLINE | ID: mdl-37914522

RESUMEN

The timing of mammalian diversification in relation to the Cretaceous-Paleogene (KPg) mass extinction continues to be a subject of substantial debate. Previous studies have either focused on limited taxonomic samples with available whole-genome data or relied on short sequence alignments coupled with extensive species samples. In the present study, we improved an existing dataset from the landmark study of Meredith et al. (2011) by filling in missing fragments and further generated another dataset containing 120 taxa and 98 exonic markers. Using these two datasets, we then constructed phylogenies for extant mammalian families, providing improved resolution of many conflicting relationships. Moreover, the timetrees generated, which were calibrated using appropriate molecular clock models and multiple fossil records, indicated that the interordinal diversification of placental mammals initiated before the Late Cretaceous period. Additionally, intraordinal diversification of both extant placental and marsupial lineages accelerated after the KPg boundary, supporting the hypothesis that the availability of numerous vacant ecological niches subsequent to the mass extinction event facilitated rapid diversification. Thus, our results support a scenario of placental radiation characterized by both basal cladogenesis and active interordinal divergences spanning from the Late Cretaceous into the Paleogene.


Asunto(s)
Marsupiales , Placenta , Humanos , Femenino , Embarazo , Animales , Filogenia , Marsupiales/genética , Alineación de Secuencia/veterinaria , Mamíferos/genética , Evolución Biológica
13.
Nat Commun ; 14(1): 5657, 2023 Sep 13.
Artículo en Inglés | MEDLINE | ID: mdl-37704654

RESUMEN

The interactions between charges and excitons involve complex many-body interactions at high densities. The exciton-polaron model has been adopted to understand the Fermi sea screening of charged excitons in monolayer transition metal dichalcogenides. The results provide good agreement with absorption measurements, which are dominated by dilute bright exciton responses. Here we investigate the Fermi sea dressing of spin-forbidden dark excitons in monolayer WSe2. With a Zeeman field, the valley-polarized dark excitons show distinct p-doping dependence in photoluminescence when the carriers reach a critical density. This density can be interpreted as the onset of strongly modified Fermi sea interactions and shifts with increasing exciton density. Through valley-selective excitation and dynamics measurements, we also infer an intervalley coupling between the dark trions and exciton-polarons mediated by the many-body interactions. Our results reveal the evolution of Fermi sea screening with increasing exciton density and the impacts of polaron-polaron interactions, which lay the foundation for understanding electronic correlations and many-body interactions in 2D systems.

14.
Chin J Integr Med ; 29(12): 1077-1086, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37528325

RESUMEN

OBJECTIVE: To reveal the anti-inflammatory mechanism of Guanxin V, which is prescribed for ventricular remodeling in clinical practice. METHODS: Guanxin V-, ventricular remodeling-, and inflammation-related targets were obtained through an integrated strategy of virtual screening and systematic pharmacology, and then the shared targets were visualised with a Venn diagram. Guanxin V network and the protein-protein interaction network were drawn, and enrichment analysis was conducted. Finally, the main results obtained from the integrated strategy were validated by molecular docking and in vivo experiments. RESULTS: A total of 251, 11,425, and 15,246 Guanxin V-, ventricular remodeling-, and inflammation-related targets were acquired, respectively. Then, 211 shared targets were considered to contribute to the mechanism of ventricular remodeling treated by Guanxin V. Guanxin network and the protein-protein interaction network were drawn, and enrichment analysis showed some cardiovascular-related biological processes and signaling pathways. Molecular docking revealed that the Guanxin V-derived compounds could align with key targets. Final in vivo experiments proved that Guanxin V reverses ventricular remodeling by inhibiting inflammation. CONCLUSION: Guanxin V relieves ventricular remodeling by regulating inflammation, which provides new ideas for the anti-ventricular remodeling mechanism of Guanxin V.


Asunto(s)
Farmacología en Red , Remodelación Ventricular , Humanos , Simulación del Acoplamiento Molecular , Inflamación/tratamiento farmacológico
15.
World J Gastroenterol ; 29(24): 3748-3757, 2023 Jun 28.
Artículo en Inglés | MEDLINE | ID: mdl-37426320

RESUMEN

Partial hepatectomy (PH) can lead to severe complications, including liver failure, due to the low regenerative capacity of the remaining liver, especially after extensive hepatectomy. Liver sinusoidal endothelial cells (LSECs), whose proliferation occurs more slowly and later than hepatocytes after PH, compose the lining of the hepatic sinusoids, which are the smallest blood vessels in the liver. Vascular endothelial growth factor (VEGF), secreted by hepatocytes, promotes LSEC proliferation. Supplementation of exogenous VEGF after hepatectomy also increases the number of LSECs in the remaining liver, thus promoting the reestablishment of the hepatic sinusoids and accelerating liver regeneration. At present, some shortcomings exist in the methods of supplementing exogenous VEGF, such as a low drug concentration in the liver and the reaching of other organs. More-over, VEGF should be administered multiple times and in large doses because of its short half-life. This review summarized the most recent findings on liver regeneration and new strategies for the localized delivery VEGF in the liver.


Asunto(s)
Hepatectomía , Regeneración Hepática , Factor A de Crecimiento Endotelial Vascular , Humanos , Células Endoteliales/metabolismo , Hepatectomía/efectos adversos , Hepatocitos/metabolismo , Hígado/metabolismo , Factor A de Crecimiento Endotelial Vascular/farmacología
16.
Zhongguo Zhong Yao Za Zhi ; 48(5): 1137-1144, 2023 Mar.
Artículo en Chino | MEDLINE | ID: mdl-37005799

RESUMEN

In order to judge the future development trend of science and technology, plan ahead and lay out the frontier technology fields and directions, China Association of Chinese Medicine(CACM) has launched consultation projects for collecting "major scienti-fic issues and engineering technology difficulties in traditional Chinese medicine(TCM)" for the industry for three consecutive years since 2019. Up to now, 18 projects have been selected as major issues for research, and some experience and achievements have been made. These projects have been applied in important scientific and technological work such as scientific and technological planning and deployment at all levels of national, local, and scientific research institutions, the selection and cultivation of major national scientific and technological projects, and the construction of innovation bases, giving full play to the role of the think tank advisory committee of CACM. This study reviewed the selection of major issues for the first time, systematically combed its application in the national layout of science and technology, and put forward the existing problems and improvement suggestions, aiming to provide new ideas for further improving the selection of major issues and research direction, providing a theoretical basis and decision support for the national scientific and technological layout in the field of TCM, and promoting scientific and technological innovation to facilitate the high quality development of TCM.


Asunto(s)
Medicamentos Herbarios Chinos , Medicina Tradicional China , Invenciones , China
17.
Zhongguo Zhong Yao Za Zhi ; 48(1): 256-264, 2023 Jan.
Artículo en Chino | MEDLINE | ID: mdl-36725278

RESUMEN

Currently,the research or publications related to the clinical comprehensive evaluation of Chinese patent medicine are increasing,which attracts the broad attention of all circles. According to the completed clinical evaluation report on Chinese patent medicine,there are still practical problems and technical difficulties such as unclear responsibility of the evaluation organization,unclear evaluation subject,miscellaneous evaluation objects,and incomplete and nonstandard evaluation process. In terms of evaluation standards and specifications,there are different types of specifications or guidelines with different emphases issued by different academic groups or relevant institutions. The professional guideline is required to guide the standardized and efficient clinical comprehensive evaluation of Chinese patent medicine and further improve the authority and quality of evaluation. In combination with the characteristics of Chinese patent medicine and the latest research achievement at home and abroad,the detailed specifications were formulated from six aspects including design,theme selection,content and index,outcome,application and appraisal,and quality control. The guideline was developed based on the guideline development requirements of China Assoication of Chinese medicine. After several rounds of expert consensus and public consultation,the current version of the guideline has been developed.


Asunto(s)
Medicamentos Herbarios Chinos , Medicina Tradicional China , Medicamentos sin Prescripción , Consenso , China , Estándares de Referencia
18.
Appl Opt ; 62(4): 1035-1045, 2023 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-36821161

RESUMEN

We examined optical trapping force (TF) exerted on non-uniform chiral stratified spheres by a high-order Bessel beam (HOBB). Present theories were proven to be valid by comparison with the existing reference. Numerical simulations considering the effects of various parameters on TF are displayed in detail. The results show that different chirality distributions in stratified chiral sphere will affect significantly the trapping characteristics, and a stable three-dimensional capture can be realized only by selecting the appropriate parameters of incident beam and particles. The theoretical investigations may provide an analytical method to help understand the interaction of light with more complex stratified chiral cells and thus become an encouraging approach to better design an optical manipulation system.

19.
IEEE Trans Neural Netw Learn Syst ; 34(2): 894-908, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-34437069

RESUMEN

This article presents several new α -passivity and α -finite-time passivity ( α -FTP) concepts for the fractional-order systems with different input and output dimensions, which are distinct from the concepts for integer-order systems and extend the existing passivity and FTP definitions to some extent. On one hand, we not only develop some sufficient conditions for ensuring the α -passivity of the multi-weighted fractional-order complex dynamical networks (MWFOCDNs) with fixed and adaptive couplings, but also discuss the synchronization for the MWFOCDNs based on the α -output-strict passivity ( α -OSP). On the other hand, the α -FTP for the MWFOCDNs with fixed and adaptive couplings are also studied on the basis of the designed state feedback controller, and the relationship between finite-time synchronization (FTS) and α -FTP for the MWFOCDNs is also illustrated. Finally, two numerical examples with simulation results are used to demonstrate the validity of the obtained criteria.

20.
Plant Biotechnol J ; 21(1): 14-16, 2023 01.
Artículo en Inglés | MEDLINE | ID: mdl-36221906

RESUMEN

PoDPBT, an O-benzoyltransferase belonging to the BAHD family, can catalyze the benzoylation of 8-debenzoylpaeoniflorin to paeoniflorin. PoDPBT is the first enzyme demonstrated to be involved in the modification stage of paeoniflorin biosynthesis. DFGGG, a new DFGWG-like motif, was revealed in the BAHD family. The transcriptome database provides a resource for further investigation of other enzyme genes involved in paeoniflorin biosynthesis.


Asunto(s)
Paeonia , Paeonia/genética , Aciltransferasas/genética , Monoterpenos , Catálisis
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