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1.
Opt Express ; 32(9): 16563-16577, 2024 Apr 22.
Artículo en Inglés | MEDLINE | ID: mdl-38859280

RESUMEN

Zero-thickness model and slab model are two important models in the description of optical behaviors in two-dimensional atomic crystals. The predicted difference in optical behaviors between the two models is very small, which is difficult to distinguish by established measurement methods. Here, we present an optical spatial differentiation method to examine the difference in edge images of different graphene layers. The theoretical results show that the edge imaging is significantly different between the two different models. When the beam reflection is at the Brewster angle, different graphene layers are used to adjust the spatial differentiation. It is shown that the slab model is more sensitive to the number of graphene layers. The zero-thickness model is more suitable for one-dimensional optical differential operation. Moreover, the spatial differentiation plays the role of a band-pass filter. The high-frequency edge information components will pass through the filter, thus realizing layer-sensitive edge-enhanced imaging. In addition, we do not focus on the verification of the exact model, but only provide an alternative method to characterize the number of graphene layers based on two models, and also provide possibilities for achieving imaging edge detection by graphene differential operators. This study may provide a possible method for the optical characterization of two-dimensional atomic crystals.

2.
Phys Rev Lett ; 132(23): 236502, 2024 Jun 07.
Artículo en Inglés | MEDLINE | ID: mdl-38905653

RESUMEN

Integer and fractional Chern insulators have been extensively explored in correlated flat band models. Recently, the prediction and experimental observation of fractional quantum anomalous Hall (FQAH) states with spontaneous time-reversal symmetry breaking have garnered attention. While the thermodynamics of integer quantum anomalous Hall (IQAH) states have been systematically studied, our theoretical knowledge on thermodynamic properties of FQAH states has been severely limited. Here, we delve into the general thermodynamic response and collective excitations of both IQAH and FQAH states within the paradigmatic flat Chern-band model with remote band considered. Our key findings include (i) in both ν=1 IQAH and ν=1/3 FQAH states, even without spin fluctuations, the charge-neutral collective excitations would lower the onset temperature of these topological states, to a value significantly smaller than the charge gap, due to band mixing and multiparticle scattering; (ii) by employing large-scale thermodynamic simulations in FQAH states in the presence of strong interband mixing between C=±1 bands, we find that the lowest collective excitations manifest as the zero-momentum excitons in the IQAH state, whereas in the FQAH state, they take the form of magnetorotons with finite momentum; (iii) the unique charge oscillations in FQAH states are exhibited with distinct experimental signatures, which we propose to detect in future experiments.

3.
Mol Biol Rep ; 51(1): 435, 2024 Mar 23.
Artículo en Inglés | MEDLINE | ID: mdl-38520543

RESUMEN

BACKGROUND: XIAP-associated factor 1 (XAF1) has been found to participate in the progression of multiple human cancers. Nevertheless, its role as well as the reaction mechanism in non-small cell lung cancer (NSCLC) still remains obscure. METHODS: In this study, the protein expression of XAF1 in NSCLC cell lines was evaluated using western blot. With the employment of CCK-8 assay, EdU staining, wound healing and transwell, capabilities of NSCLC cells to proliferate, migrate and invade were assessed. Cell apoptotic level and cell cycle were resolved utilizing flow cytometry. Western blot was applied for the estimation of apoptosis- and endoplasmic reticulum (ER) stress-related proteins. RESULTS: It was discovered that XAF1 expression was conspicuously reduced in NSCLC cell lines. XAF1 overexpression suppressed H1299 cell proliferative, invasive and migrative capabilities, but exhibited promotive effects on cell cycle arrest. Meanwhile, XAF1 overexpression inhibited cisplatin resistance in H1299 and H1299/DDP cells by promoting cell apoptosis and enhanced the expression levels of ER stress-related proteins CHOP, GRP78 and ATF4. What's more, 4-PBA treatment reversed the impacts of XAF1 overexpression on the proliferative, invasive, migrative and apoptotic capabilities of H1299 cells, as well as cell cycle and cisplatin resistance. CONCLUSION: In conclusion, XAF1 overexpression impeded the advancement of NSCLC and repressed cisplatin resistance of NSCLC cells through inducing ER stress, which indicated that XAF1 might be a novel targeted-therapy for NSCLC.


Asunto(s)
Carcinoma de Pulmón de Células no Pequeñas , Neoplasias Pulmonares , MicroARNs , Humanos , Proteínas Adaptadoras Transductoras de Señales/metabolismo , Apoptosis/genética , Proteínas Reguladoras de la Apoptosis/metabolismo , Carcinoma de Pulmón de Células no Pequeñas/patología , Línea Celular Tumoral , Proliferación Celular , Cisplatino/farmacología , Resistencia a Antineoplásicos/genética , Estrés del Retículo Endoplásmico/genética , Neoplasias Pulmonares/tratamiento farmacológico , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/metabolismo , MicroARNs/metabolismo
4.
J Environ Manage ; 351: 119794, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38081088

RESUMEN

Exploring the spatiotemporal characteristics of ecosystem services (ESs) and their drivers is crucial for managers to develop significant scientific policies that further sustainable development. We used the Yangtze River Economic Belt (YREB) to explore the trends, hotspots, and drivers of water yield (WY), soil conservation (SC), carbon sequestration (CS), and food supply (FS) between 2000 and 2020. Similarly, we analyzed relationships among ESs and drivers of the multiple ecosystem services landscape index (MESLI). We used the self-organizing map method to obtain the types and distribution of the ES bundles, revealing the bundles, trade-offs, and synergies among ESs. The four ESs had an increasing trend, with CS having the highest increase; ES hotspot analysis showed differences among upper, middle, and lower reaches. Constraint lines among ESs and drivers were diverse; the corresponding SC and WY reached thresholds when CS values were 1477.81 and 460.5 t km-2, respectively. When FS values were 67.34 and 86.17 × 104 Yuan·km-2, CS and WY reached their thresholds. All critical drivers of the four ESs were natural factors. The thresholds that the MESLI reached with driver status were 1000 mm (evapotranspiration), 2121 mm (precipitation), 2.42° (slope), 1.46% (soil organic matter), 36.08% (sand), 30.75% (proportion of non-agricultural population), 18.57% (cropland proportion), 1.05 × 104 persons·km-2 (population density), and 84.84% (proportion of non-agricultural industries in total gross domestic product), respectively. FS, water supply, and ecological conservation bundles changed over the 20 years, and trade-offs and synergies among ESs within bundles differed. We revealed the complexity of ESs from multiple perspectives, which will enable the development of ecosystem management and conservation recommendations for the YREB and large-scale economic zones worldwide.


Asunto(s)
Conservación de los Recursos Naturales , Ecosistema , Conservación de los Recursos Naturales/métodos , Ríos , Suelo , China
5.
J Environ Manage ; 355: 120468, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38430883

RESUMEN

Soil depth plays a crucial role in shaping the interactions between soil microbes and nutrient availability. However, there is limited understanding of how bacterial, fungal, and protistan communities respond to different soil depths, particularly in the unique geological context and soil properties of karst regions. Organic matter, total nitrogen, and phosphorus, ammonium, nitrate, and plant root biomass, as well as bacterial and fungal abundances, bacterial and protistan diversity were higher in the 0-20 cm soil layer than those in the 20-40 cm and soil-rock mixing layers. In contrast, soil pH was higher in the 20-40 cm and soil-rock mixing layers than that in the 0-20 cm soil layer. The soil exchange of calcium, nitrate, and root biomass were identified as the primary factors regulating microbial assemblages across the depth transect. Moreover, co-occurrence network analysis revealed a greater degree of connectivity between protistan taxa and fungal taxa in the 0-20 cm soil layer than those in the 20-40 cm and soil-rock mixing layers. In contrast, the number of association links between protist-bacteria and bacteria-bacteria was higher in the soil-rock mixing layers compared to the 0-20 cm soil layer. Actinobacteria, Ascomycota, and unclassified protistan taxa were identified as keystones, displaying the highest number of connections with other microbial taxa. Collectively, these results suggested that the increased plant root biomass, coupled with sufficient available nutrient inputs in the upper 0-20 cm soil layer, facilitates strong interactions among fungal and protistan taxa, which play crucial roles in the topsoil. However, as nutrients become less available with increasing depth, competition among bacterial taxa and the predation between bacterial and protistan taxa intensify. Therefore, these findings indicate the interactions among keystone taxa at different soil depths has the potential to generate ecological implications during vegetation restoration in fragile ecosystems.


Asunto(s)
Ecosistema , Suelo , Biomasa , Suelo/química , Hongos , Nitratos , Bacterias , Microbiología del Suelo
6.
Arch Virol ; 168(11): 276, 2023 Oct 20.
Artículo en Inglés | MEDLINE | ID: mdl-37864004

RESUMEN

A new virulent phage, SWEP2, infecting the Arthrobacter sp. 5B strain, was isolated from black soil samples in northeastern China. SWEP2 has a latent period of 80 min and a burst size of 45 PFU (evaluated at an MOI of 0.1). Genomic analysis revealed that the 43,398-bp dsDNA genome of phage SWEP2 contains 64 open reading frames (ORFs) and one tRNA gene. Phylogenetic analysis indicated a close relationship between SWEP2 and Arthrobacter phage Liebe, with 82.98% identity and a query coverage of 48%. Based on its distinct phenotypic and genetic characteristics, SWEP2 is identified as a novel Arthrobacter phage.


Asunto(s)
Arthrobacter , Bacteriófagos , Arthrobacter/genética , Filogenia , Genoma Viral , Genómica , Sistemas de Lectura Abierta
7.
Plant Dis ; 2023 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-36723963

RESUMEN

During April 2022, leaf spot was observed on strawberry (Fragaria × ananassa Duch.) with a disease incidence of approximately 45% among 100 plants. Strawberry was cultivated in a nursery at Huzhou University (30.87゜N, 120.13゜E), Zhejiang Province, China. In the strawberry greenhouse, the average temperature was 15-18 degrees, 40%-60% humidity. Early symptoms appeared as dark brown or black spotted necrotic lesions, which expanded from 2 to 6 mm in diameter. Dark brown spots with yellow halos occupied half of the leaf area and eventually developed leaf blight with large yellow halos. To isolate the causal agent, 0.5 cm x 0.5 cm fragments were cut from three symptomatic leaves, and were surface sterilized with 75% ethanol for 30 s and then rinsed three times with sterilized water. The airdried leaf fragments were placed on PDA with 50 µg/ml ampicillin and incubated in the dark at 25℃ for two days. Isolates were obtained by transferring hyphal plugs of 1 mm in diameter onto PDA. The colony morphology was circular and dark brown on the upperside and black on the underside, with cottony mycelium and an large amount of gray aerial mycelium. Conidia were large, light olive-brown to dark olive-brown and light olive-black and septate. The typical conidia were oval or rod-shaped, rarely curved, and dark septa defined the basal and apical cells. In the two typical forms of conidia, the average size of oval conidia was approximately 18.77 × 54.92 µm (11.99 to 26.97 × 35.13 to 74.59 µm, n = 20), and the average size of the rod-shaped conidia was approximately 14.80 × 103.24 µm (11.24 to 24.64 × 73.11 to 131.51 µm, n = 20). The morphological characteristics matched well with previous descriptions of Exserohilum rostratum (Sharma et al. 2014; Liu et al. 2021). The identity of C1-L and C1-S from symptomatic tissues was confirmed by means of multi-locus gene sequencing. Genomic DNA was extracted from the mycelium using the CTAB (cetyltrimethylammonium bromide) method (Griffith & Shaw 1998). Molecular identification was conducted by sequencing the internal transcribed spacer (ITS) rDNA region, partial glyceraldehyde-3-phosphate dehydrogenase (GAPDH) gene, partial actin (ACT) gene, and partial beta-tubulin 2 (TUB2), using the primers ITS1/ITS4 (White et al. 1990), GDF/GDR (Templeton et al. 1992), ACT512F/ACT783R (Carbone and Kohn 1999), T1 (O'Donnell and Cigelnik 1997) and Bt2b (Glass and Donaldson, 1995). The obtained sequences of C1-L and C1-S were the same. Moreover, the sequences have been deposited in GenBank under accession numbers ON982516 (ITS), ON996915 (GAPDH), ON996916 (ACT), and ON996917 (TUB2). The results of Basic Local Alignment Search Tool (BLAST) analysis revealed that the ITS, GAPDH, and ACT had 100% identity with the sequences of E. rostratum (GenBank Accession No. LT837834, LT883550, and LT837672, respectively), the TUB2 had 99.61% similarity with BLAST sequences of E. rostratum (LT899391). These morphological characteristics and molecular analyses allowed the identification of the pathogen as E. rostratum. Koch's postulates were performed with five healthy detached strawberry leaves with three inoculations per leaf of the 'Akihime' strawberry variety. Surface-sterilized leaves were wounded with an aseptic needle, and inoculated with 2 mm diameter mycelial plugs from 5-day-old cultures of E. rostratum. Control leaves were also wounded with the aseptic needle, and inoculated with a sterile PDA agar plug. The leaves were incubated at 25℃ in Petri plates with petioles wrapped in moist sterile cotton. The diseased symptoms included black spots on the epidermis of the wounded leaves within 5, 10, and 20 days after inoculation. Mock-inoculated controls remained asymptomatic, and three biological repetitions were conducted. The fungus reisolated from the diseased leaves was confirmed as E. rostratum by sequencing. Abundant reports have shown that E. rostratum can infect many economically important crops such as maize, rice, and pineapple (Sun et al. 2021; Kabore et al. 2022; Luo et al. 2012). To the best of our knowledge, this is the first report of E. rostratum on strawberry in China and worldwide.

8.
Langmuir ; 38(19): 6086-6098, 2022 05 17.
Artículo en Inglés | MEDLINE | ID: mdl-35504860

RESUMEN

Oceanic oil spill and the discharge of industrial oily wastewaters can cause significant threats to the ecological environment and human health. Herein, we design a durable TiO2/PDA-based superhydrophobic paper for efficient oil/water separation. Bioinspired from mussel adhesive proteins, the mechanical durability of the as-prepared superhydrophobic paper is enhanced by the deposition of polydopamine (PDA) onto cellulosic fibers via self-polymerization of dopamine. The TiO2/PDA-based superhydrophobic paper shows a high water contact angle of 168.2° and an oil contact angle of ∼0°, exhibiting excellent superhydrophobicity and superoleophilicity. Furthermore, the as-prepared superhydrophobic paper possesses excellent chemical stability, thermal stability, and mechanical durability in terms of being immersed in corrosive solutions and solvents and boiling water and being subjected to the sandpaper abrasion test, respectively. More importantly, the separation efficiency of the TiO2/PDA-based superhydrophobic paper for an oil/water mixture is 97.2%, and it maintains a separation efficiency above 94.3% even after 15 cyclic separation processes. Furthermore, the separation efficiency for water-in-oil emulsions is higher than 93.7% after 15 cyclic separation tests, showing its excellent recyclable stability for water-in-oil emulsions. Therefore, the rationally designed TiO2/PDA-based superhydrophobic paper shows great potential in the practical applications of self-cleaning, antifouling, and oil/water separation.


Asunto(s)
Polímeros , Emulsiones , Humanos , Interacciones Hidrofóbicas e Hidrofílicas , Indoles , Polímeros/química , Titanio
9.
Phys Rev Lett ; 126(22): 227201, 2021 Jun 04.
Artículo en Inglés | MEDLINE | ID: mdl-34152175

RESUMEN

We investigate the amplitude (Higgs) mode associated with longitudinal fluctuations of the order parameter at the continuous spontaneous symmetry breaking phase transition. In quantum magnets, due to the fast decay of the amplitude mode into low-energy Goldstone excitations, direct observation of this mode represents a challenging task. By focusing on a quasi-one-dimensional geometry, we circumvent the difficulty and investigate the amplitude mode in a system of weakly coupled spin chains with the help of quantum Monte Carlo simulations, stochastic analytic continuation, and a chain-mean field approach combined with a mapping to the field-theoretic sine-Gordon model. The amplitude mode is observed to emerge in the longitudinal spin susceptibility in the presence of a weak symmetry-breaking staggered field. A conventional measure of the amplitude mode in higher dimensions, the singlet bond mode, is found to appear at a lower than the amplitude mode frequency. We identify these two excitations with the second (first) breather of the sine-Gordon theory, correspondingly. In contrast to higher-dimensional systems, the amplitude and bond order fluctuations are found to carry significant spectral weight in the quasi-1D limit.

10.
Arch Virol ; 166(11): 3183-3188, 2021 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-34505918

RESUMEN

A new Bacillus cereus phage, SWEP1, was isolated from black soil. The host lysis activity of phage SWEP1 has a relatively short latent time (20 min) and a small burst size of 83 PFU. The genome of SWEP1 consists of 162,461 bp with 37.77% G+C content. The phage encodes 278 predicted proteins, 103 of which were assigned functionally. No tRNA genes were found. Comparative genomics analysis indicated that SWEP1 is related to Bacillus phage B4 (86.91% identity, 90% query coverage). Phenotypic and genotypic characterization suggested that SWEP1 is a new member of a new species in the genus Bequatrovirus, family Herelleviridae.


Asunto(s)
Fagos de Bacillus/fisiología , Bacillus cereus/virología , Genoma Viral , Fagos de Bacillus/genética , Fagos de Bacillus/aislamiento & purificación , Bacillus cereus/aislamiento & purificación , Composición de Base , Replicación del ADN/genética , Genómica , Genotipo , Microscopía Electrónica de Transmisión , Filogenia , ARN de Transferencia/genética , Microbiología del Suelo , Temperatura
12.
Anal Biochem ; 553: 1-6, 2018 07 15.
Artículo en Inglés | MEDLINE | ID: mdl-29750943

RESUMEN

Although annonaceous acetogenins (ACGs) have been reported to have antitumor activity for over three decades, and many of the underlying mechanism of ACGs on cancer have been clarified, there are still outstanding issues. In particular, the changes of small metabolite in cancer cells, caused by ACGs intake, have been reported rarely. Recent research has showed that cellular metabolic profiling coupled with ultra-flow liquid chromatography coupled to quadrupole-time-of-flight mass spectrometry (UFLC-Q-TOF-MS) and multivariable statistical analysis enables a good understanding of ACGs' effects on multidrug resistant human mammary adenocarcinoma (MCF-7/Adr) cells. As a result, 23 potential biomarkers (p < 0.05, VIP >1) were identified, and 5 pathways (impact-value > 0.10) identified. The differential metabolites suggested that ACGs affected metabolomics pathways, including arginine and proline metabolism, glycerophospholipid metabolism, taurine and hypotaurine metabolism, alanine, aspartate and glutamate metabolism and D-Glutamine and D-glutamate metabolism.


Asunto(s)
Acetogeninas/farmacología , Adenocarcinoma/patología , Resistencia a Múltiples Medicamentos , Resistencia a Antineoplásicos , Neoplasias Mamarias Animales/patología , Metabolómica , Animales , Arginina/metabolismo , Línea Celular Tumoral , Glicerofosfolípidos/metabolismo , Humanos , Prolina/metabolismo
13.
Phys Rev Lett ; 117(6): 066403, 2016 Aug 05.
Artículo en Inglés | MEDLINE | ID: mdl-27541471

RESUMEN

We propose a general scheme for diagnosing interaction-driven topological phases in the weak interaction regime using exact diagonalization (ED). The scheme comprises the analysis of eigenvalues of the point-group operators for the many-body eigenstates and the correlation functions for physical observables to extract the symmetries of the order parameters and the topological numbers of the underlying ground states at the thermodynamic limit from a relatively small size system afforded by ED. As a concrete example, we investigate the interaction effects on the half-filled spinless fermions on the checkerboard lattice with a quadratic band crossing point. Numerical results support the existence of a spontaneous quantum anomalous Hall phase purely driven by a nearest-neighbor weak repulsive interaction, separated from a nematic Mott insulator phase at strong repulsive interaction by a first-order phase transition.

14.
Mater Horiz ; 11(11): 2749-2758, 2024 Jun 03.
Artículo en Inglés | MEDLINE | ID: mdl-38533828

RESUMEN

The intricate correlation between lattice geometry, topological behavior and charge degrees of freedom plays a key role in determining the physical and chemical properties of a quantum-magnetic system. Herein, we investigate the introduction of the unusual oxidation state as an alternative pathway to modulate the magnetic ground state in the well-known S = 1 Haldane system nickelate Y2BaNiO5 (YBNO). YBNO is topologically reduced to incorporate d9-Ni+ (S = 1/2) in the one-dimensional Haldane chain system. The random distribution of Ni+ for the first time results in the emergence of a one-dimensional ferromagnetic phase with a transition temperature far above room temperature. Theoretical calculations reveal that the antiferromagnetic interplay can evolve into ferromagnetic interactions with the presence of oxygen vacancies, which promotes the formation of ferromagnetic order within one-dimensional nickel chains. The unusual electronic instabilities in the nickel-based Haldane system may offer new possibilities towards unconventional physical and chemical properties from quantum interactions.

15.
Inorg Chem ; 52(18): 10566-70, 2013 Sep 16.
Artículo en Inglés | MEDLINE | ID: mdl-23977843

RESUMEN

Three new mixed-metal borates, K4Ba2[B14O20(OH)10]·3H2O (1), LiSr2[B10O16(OH)3] (2), and LiBa[B9O15] (3), have been made under hydro(solvo)thermal conditions and characterized by means of IR, UV-vis-near-IR, thermogravimetric analysis, powder X-ray diffraction, and single-crystal X-ray diffraction, respectively. 1 is a 1D chain constructed from B14O21(OH)10(10-) cluster units, 2 is of a 2D layer with nine-membered-ring windows built up of B10O19(OH)3(9-) cluster units, while 3 exhibits a 3D framework with 12-membered-ring channels composed of B3O7 cluster units.

16.
Food Chem ; 419: 136033, 2023 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-37011574

RESUMEN

Fluorescent sensors had been extensively applied on sensing various biomolecules effectively, but no fluorescent sensor for oleanolic acid was presented up to now. In this work, the first fluorescent sensor for oleanolic acid was designed and synthesized based on o-phenyl-bridged bis-tetraphenylimidazole (PTPI). PTPI was prepared by bridging two tetraphenylimidazole units and o-phenylenediamine via Schiff-base condensation in yield of 86%. PTPI showed high sensing selectivity for oleanolic acid among 26 biomolecules and ions. The blue fluorescence at 482 nm was enhanced by 4.5 times after sensing oleanolic acid in aqueous media. The fluorescence sensing ability of PTPI for oleanolic acid maintained stable in pH = 5-9. The detecting limitation was as low as 0.032 µM. The detecting mechanism was clarified as 1:1 binding stoichiometry by fluorescence Job's plot, mass spectrometry, 1H nuclear magnetic resonance and fourier transform infrared spectroscopy. The detecting ability of PTPI for oleanolic acid was successfully used for paper test and real samples of grapes and Kuding tea with recoveries in the range of 96.0%-106.0%, indicating the good application potential for on-site detecting oleanolic acid in real samples of fruits and food.


Asunto(s)
Ácido Oleanólico , Colorantes Fluorescentes/química , Alimentos , Bases de Schiff/química , Espectrometría de Fluorescencia , Agua/química , Imidazoles/química
17.
Environ Sci Pollut Res Int ; 30(51): 110562-110578, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37792185

RESUMEN

Understanding the response mechanism of ecosystem services (ES) to landscape patterns is important in regional landscape planning and sustainable development. In this study, the landscape index and InVEST model were used to quantitatively analyze the spatio-temporal evolution of landscape patterns and ES in the Ganjiang River Basin of China from 1990 to 2020. Furthermore, the bivariate Moran's I method and spatial error model were used to test the spatial correlation between landscape index and ES. The results showed that (1) cropland decreased and construction land increased, and the overall landscape tended to be fragmented, the patch shape complicated, and landscape diversity increased from 1990 to 2020. Water conservation (WC) and soil conservation (SC) capacity increased by 10.56 mm and 16.24 t hm-2 a-1, respectively, whereas carbon storage (CS) decreased by 1.22 t hm-2 a-1. (2) The responses of different typical ES to landscape patterns were different in the landscape index and response degree. Typical ES negatively responded to Shannon's diversity index and patch density. WC was sensitive to the Splitting Index, whereas SC and CS were more responsive to the average patch area. (3) The overall purpose of territorial spatial planning within a basin should be to reduce the fragmentation and heterogeneity of the landscape. According to four local aggregation patterns of landscape index and ES, corresponding measures can be taken according to local conditions in different regions. These results can provide a quantitative basis for landscape management and ecological construction in the Ganjiang River Basin and scientific guidance for the Yangtze River conservation strategy.


Asunto(s)
Ecosistema , Ríos , Conservación de los Recursos Naturales , China
18.
Zhongguo Zhen Jiu ; 43(2): 203-6, 2023 Feb 12.
Artículo en Zh | MEDLINE | ID: mdl-36808516

RESUMEN

The paper presents professor WU Han-qing's experience in treatment of lumbar disc herniation (LDH) with "sinew-bone three needling technique" of Chinese medicine. Based on the theory of meridian sinew, the points are located by "three-pass method" in terms of the distribution of meridian sinew and syndrome/pattern differentiation. The cord-like muscles and adhesion are relieved by relaxing technique to work directly on the affected sites and alleviate the local compression to the nerve root. The needle technique is operated flexibly according to the affected regions involved, due to which, the needling sensation is increased while the safety ensured. As a result, the meridian qi is enhanced, the mind and qi circulation is regulated; and the clinical effect is improved.


Asunto(s)
Terapia por Acupuntura , Desplazamiento del Disco Intervertebral , Meridianos , Humanos , Medicina Tradicional China , Desplazamiento del Disco Intervertebral/terapia , Terapia por Acupuntura/métodos , Procedimientos Quirúrgicos Vasculares , Puntos de Acupuntura
19.
Adv Mater ; 35(1): e2203411, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-36300686

RESUMEN

As a crucial concept in magnetism and spintronics, exchange bias (ExB) measures the asymmetry in the hysteresis loop of a pinned ferromagnet (FM)/antiferromagnet (AFM) interface. Previous studies are mainly focused on FM/AFM heterostructures composed of conventional bulk materials, whose complex interfaces prohibit precise control and full understanding of the phenomenon. Here, the enabling power of 2D magnets is exploited to demonstrate the emergence, non-aging, extendability, and rechargeability of ExB in van der Waals Fe3 GeTe2 homostructures, upon moderate pressuring. The emergence of the ExB is attributed to a local stress-induced FM-to-AFM transition, as validated using first-principles calculations, and confirmed in magneto-optical Kerr effect and second harmonic generation measurements. It is also observed that, negligible ExB aging before the training effect suddenly takes place through avalanching, pronounced delay of the avalanche via timed pressure repetition (extendability), ExB recovery in the post-training sample upon refreshed pressuring (rechargeability), and demonstrate its versatile tunability. These striking findings offer unprecedented insights into the underlying principles of ExB and its training, with immense technological applications in sight.

20.
Pancreatology ; 12(2): 170-8, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-22487528

RESUMEN

BACKGROUND & AIMS: Hypoxia is a common characteristic of solid tumors. Recent studies confirmed that Toll-like receptor 4 (TLR4) plays a significant role in cancer invasion and progression. In this study, the correlation between the expression of TLR4 and the change of the protein level of Hypoxia-inducible factor-1 alpha (HIF-1α) was studied. METHODS: We examined 84 human pancreatic cancer tissues for expression of HIF-1α and TLR4 proteins. Panc-1 cells were exposed to normoxia (20% O(2)) or hypoxia (<1% O(2)) or treated with CoCl(2). TLR4 protein was analyzed by flow cytometry and immunostaining. Growth studies were conducted on cells with the HIF-1α inhibition isolated from stable transfected cell lines. Finally, TLR4 protein was detected by immunohistochemistry in vivo tumors. RESULTS: There was a positive correlation between TLR4 and HIF-1α protein in pancreatic cancer tissues. Hypoxic stress induced TLR4 mRNA and protein expression in Panc-1 cells. Cells transfected with HIF-1α siRNA showed attenuation of hypoxia stress-induced TLR4 expression. In vivo growth decreased in response to TLR4 and HIF-1α inhibiton. Transient HIF-1α siRNA treatment could effectively curb tumor growth in vivo. CONCLUSION: These results suggest that TLR4 expression in pancreatic cancer cells is up-regulated via HIF-1α in response to hypoxic stress and underscore the crucial role of HIF-1α-induced TLR4 in tumor growth.


Asunto(s)
Adenocarcinoma/metabolismo , Hipoxia de la Célula/fisiología , Subunidad alfa del Factor 1 Inducible por Hipoxia/metabolismo , Neoplasias Pancreáticas/metabolismo , Receptor Toll-Like 4/metabolismo , Adenocarcinoma/tratamiento farmacológico , Adenocarcinoma/secundario , Adulto , Anciano , Animales , Hipoxia de la Célula/efectos de los fármacos , Línea Celular Tumoral , Cobalto/farmacología , Ensayos de Selección de Medicamentos Antitumorales , Regulación Neoplásica de la Expresión Génica , Silenciador del Gen , Humanos , Subunidad alfa del Factor 1 Inducible por Hipoxia/antagonistas & inhibidores , Ganglios Linfáticos/patología , Metástasis Linfática , Masculino , Ratones , Ratones Endogámicos BALB C , Ratones Desnudos , Persona de Mediana Edad , Estadificación de Neoplasias , Estrés Oxidativo , Oxígeno/administración & dosificación , Neoplasias Pancreáticas/tratamiento farmacológico , Neoplasias Pancreáticas/patología , ARN Interferente Pequeño/genética , Receptor Toll-Like 4/genética , Transfección , Regulación hacia Arriba
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