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1.
Cell ; 187(6): 1387-1401.e13, 2024 Mar 14.
Artículo en Inglés | MEDLINE | ID: mdl-38412859

RESUMEN

The Crumbs homolog 1 (CRB1) gene is associated with retinal degeneration, most commonly Leber congenital amaurosis (LCA) and retinitis pigmentosa (RP). Here, we demonstrate that murine retinas bearing the Rd8 mutation of Crb1 are characterized by the presence of intralesional bacteria. While normal CRB1 expression was enriched in the apical junctional complexes of retinal pigment epithelium and colonic enterocytes, Crb1 mutations dampened its expression at both sites. Consequent impairment of the outer blood retinal barrier and colonic intestinal epithelial barrier in Rd8 mice led to the translocation of intestinal bacteria from the lower gastrointestinal (GI) tract to the retina, resulting in secondary retinal degeneration. Either the depletion of bacteria systemically or the reintroduction of normal Crb1 expression colonically rescued Rd8-mutation-associated retinal degeneration without reversing the retinal barrier breach. Our data elucidate the pathogenesis of Crb1-mutation-associated retinal degenerations and suggest that antimicrobial agents have the potential to treat this devastating blinding disease.


Asunto(s)
Proteínas del Tejido Nervioso , Degeneración Retiniana , Animales , Ratones , Traslocación Bacteriana , Proteínas del Ojo/genética , Amaurosis Congénita de Leber/genética , Mutación , Proteínas del Tejido Nervioso/genética , Proteínas del Tejido Nervioso/metabolismo , Retina/metabolismo , Degeneración Retiniana/genética , Retinitis Pigmentosa/genética , Retinitis Pigmentosa/metabolismo , Retinitis Pigmentosa/patología
2.
Nature ; 589(7841): 214-219, 2021 01.
Artículo en Inglés | MEDLINE | ID: mdl-33408416

RESUMEN

Quantum key distribution (QKD)1,2 has the potential to enable secure communication and information transfer3. In the laboratory, the feasibility of point-to-point QKD is evident from the early proof-of-concept demonstration in the laboratory over 32 centimetres4; this distance was later extended to the 100-kilometre scale5,6 with decoy-state QKD and more recently to the 500-kilometre scale7-10 with measurement-device-independent QKD. Several small-scale QKD networks have also been tested outside the laboratory11-14. However, a global QKD network requires a practically (not just theoretically) secure and reliable QKD network that can be used by a large number of users distributed over a wide area15. Quantum repeaters16,17 could in principle provide a viable option for such a global network, but they cannot be deployed using current technology18. Here we demonstrate an integrated space-to-ground quantum communication network that combines a large-scale fibre network of more than 700 fibre QKD links and two high-speed satellite-to-ground free-space QKD links. Using a trusted relay structure, the fibre network on the ground covers more than 2,000 kilometres, provides practical security against the imperfections of realistic devices, and maintains long-term reliability and stability. The satellite-to-ground QKD achieves an average secret-key rate of 47.8 kilobits per second for a typical satellite pass-more than 40 times higher than achieved previously. Moreover, its channel loss is comparable to that between a geostationary satellite and the ground, making the construction of more versatile and ultralong quantum links via geosynchronous satellites feasible. Finally, by integrating the fibre and free-space QKD links, the QKD network is extended to a remote node more than 2,600 kilometres away, enabling any user in the network to communicate with any other, up to a total distance of 4,600 kilometres.

3.
Nature ; 582(7813): 501-505, 2020 06.
Artículo en Inglés | MEDLINE | ID: mdl-32541968

RESUMEN

Quantum key distribution (QKD)1-3 is a theoretically secure way of sharing secret keys between remote users. It has been demonstrated in a laboratory over a coiled optical fibre up to 404 kilometres long4-7. In the field, point-to-point QKD has been achieved from a satellite to a ground station up to 1,200 kilometres away8-10. However, real-world QKD-based cryptography targets physically separated users on the Earth, for which the maximum distance has been about 100 kilometres11,12. The use of trusted relays can extend these distances from across a typical metropolitan area13-16 to intercity17 and even intercontinental distances18. However, relays pose security risks, which can be avoided by using entanglement-based QKD, which has inherent source-independent security19,20. Long-distance entanglement distribution can be realized using quantum repeaters21, but the related technology is still immature for practical implementations22. The obvious alternative for extending the range of quantum communication without compromising its security is satellite-based QKD, but so far satellite-based entanglement distribution has not been efficient23 enough to support QKD. Here we demonstrate entanglement-based QKD between two ground stations separated by 1,120 kilometres at a finite secret-key rate of 0.12 bits per second, without the need for trusted relays. Entangled photon pairs were distributed via two bidirectional downlinks from the Micius satellite to two ground observatories in Delingha and Nanshan in China. The development of a high-efficiency telescope and follow-up optics crucially improved the link efficiency. The generated keys are secure for realistic devices, because our ground receivers were carefully designed to guarantee fair sampling and immunity to all known side channels24,25. Our method not only increases the secure distance on the ground tenfold but also increases the practical security of QKD to an unprecedented level.

4.
Brief Bioinform ; 24(6)2023 09 22.
Artículo en Inglés | MEDLINE | ID: mdl-37930028

RESUMEN

Technological advances have now made it possible to simultaneously profile the changes of epigenomic, transcriptomic and proteomic at the single cell level, allowing a more unified view of cellular phenotypes and heterogeneities. However, current computational tools for single-cell multi-omics data integration are mainly tailored for bi-modality data, so new tools are urgently needed to integrate tri-modality data with complex associations. To this end, we develop scMHNN to integrate single-cell multi-omics data based on hypergraph neural network. After modeling the complex data associations among various modalities, scMHNN performs message passing process on the multi-omics hypergraph, which can capture the high-order data relationships and integrate the multiple heterogeneous features. Followingly, scMHNN learns discriminative cell representation via a dual-contrastive loss in self-supervised manner. Based on the pretrained hypergraph encoder, we further introduce the pre-training and fine-tuning paradigm, which allows more accurate cell-type annotation with only a small number of labeled cells as reference. Benchmarking results on real and simulated single-cell tri-modality datasets indicate that scMHNN outperforms other competing methods on both cell clustering and cell-type annotation tasks. In addition, we also demonstrate scMHNN facilitates various downstream tasks, such as cell marker detection and enrichment analysis.


Asunto(s)
Epigenómica , Transcriptoma , Proteómica , Perfilación de la Expresión Génica , Redes Neurales de la Computación
5.
J Am Chem Soc ; 146(9): 6336-6344, 2024 Mar 06.
Artículo en Inglés | MEDLINE | ID: mdl-38381858

RESUMEN

Actuating materials convert different forms of energy into mechanical responses. To satisfy various application scenarios, they are desired to have rich categories, novel functionalities, clear structure-property relationships, fast responses, and, in particular, giant and reversible shape changes. Herein, we report a phase transition-driven ferroelectric crystal, (rac-3-HOPD)PbI3 (3-HOPD = 3-hydroxypiperidine cation), showing intriguingly large and anisotropic room-temperature actuating behaviors. The crystal consists of rigid one-dimensional [PbI3] anionic chains running along the a-axis and discrete disk-like cations loosely wrapping around the chains, leaving room for anisotropic shape changes in both the b- and c-axes. The shape change is switched by a ferroelectric phase transition occurring at around room temperature (294 K), driven by the exceptionally synergistic order-disorder and displacive phase transition. The rotation of the cations exerts internal pressure on the stacking structure to trigger an exceptionally large displacement of the inorganic chains, corresponding to a crystal lattice transformation with length changes of +24.6% and -17.5% along the b- and c-axis, respectively. Single crystal-based prototype devices of circuit switches and elevators have been fabricated by exploiting the unconventional negative temperature-dependent actuating behaviors. This work provides a new model for the development of multifunctional mechanically responsive materials.

6.
Small ; 20(5): e2305909, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-37759426

RESUMEN

The research on systems with coexistence of superconductivity and nontrivial band topology has attracted widespread attention. However, the limited availability of material platforms severely hinders the research progress. Here, it reports the first experimental synthesis and measurement of high-quality single crystal van der Waals transition-metal dichalcogenide InNbS2 , revealing it as a topological nodal line semimetal with coexisting superconductivity. The temperature-dependent measurements of magnetization susceptibility and electrical transport show that InNbS2 is a type-II superconductor with a transition temperature Tc of 6 K. First-principles calculations predict multiple topological nodal ring states close to the Fermi level in the presence of spin-orbit coupling. Similar features are also observed in the as-synthesized BiNbS2 and PbNbS2 samples. This work provides new material platforms ANbS2 (A = In, Bi, and Pb) and uncovers their intriguing potential for exploring the interplay between superconductivity and band topology.

7.
Small ; : e2403002, 2024 Jun 25.
Artículo en Inglés | MEDLINE | ID: mdl-38923293

RESUMEN

Van der Waals (vdW) magnetic materials have broad application prospects in next-generation spintronics. Inserting magnetic elements into nonmagnetic vdW materials can introduce magnetism and enhance various transport properties. Herein, the unconventional magnetic and magneto-transport phenomena is reported in Ni0.28TaSeS crystal by intercalating Ni atoms into nonmagnetic 2H-TaSeS matrix. Magnetic characterization reveals a canted magnetic structure in Ni0.28TaSeS, which results in an antiferromagnetic (AFM) order along the c-axis and a ferromagnetic (FM) moment in the ab-plane. The presence of spin-flop (SF) behavior can also be attributed to the canted magnetic structure. Temperature-dependent resistivity exhibits a metallic behavior with an abrupt decrease corresponding to the magnetic transition. Magneto-transport measurements demonstrate a positive magnetoresistance (MR) with a plateau that is different from conventional magnetic materials. The field-dependent Hall signal exhibits nonlinear field dependence when the material is in magnetically ordered state. These unconventional magneto-transport behaviors are attributed to the field-induced formation of a complex spin texture in Ni0.28TaSeS. In addition, it further investigated the angle dependence of MR and observed an unusual fourfold anisotropic magnetoresistance (AMR) effect. This work inspires future research on spintronic devices utilizing magnetic atom-intercalated quasi-2D materials.

8.
Catheter Cardiovasc Interv ; 103(7): 1148-1151, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38639161

RESUMEN

The transcatheter edge-to-edge mitral valve repair (TEER) has been recommended as a reliable treatment option for selected patients with severe degenerative and functional mitral regurgitation (MR). Although MR patients with rheumatic etiology were excluded from two significant trials (EVEREST II and COAPT) that established a role for the TEER in degenerative and functional MR. However, it has been reported that the TEER procedure could be safely and effectively performed in carefully selected rheumatic MR patients. Therefore, we share a case report of successfully treating severe rheumatic MR using a novel-designed TEER system (JensClipTM).


Asunto(s)
Cateterismo Cardíaco , Implantación de Prótesis de Válvulas Cardíacas , Insuficiencia de la Válvula Mitral , Válvula Mitral , Cardiopatía Reumática , Índice de Severidad de la Enfermedad , Humanos , Insuficiencia de la Válvula Mitral/diagnóstico por imagen , Insuficiencia de la Válvula Mitral/cirugía , Insuficiencia de la Válvula Mitral/fisiopatología , Insuficiencia de la Válvula Mitral/etiología , Cateterismo Cardíaco/instrumentación , Resultado del Tratamiento , Cardiopatía Reumática/diagnóstico por imagen , Cardiopatía Reumática/cirugía , Cardiopatía Reumática/fisiopatología , Cardiopatía Reumática/terapia , Válvula Mitral/diagnóstico por imagen , Válvula Mitral/cirugía , Válvula Mitral/fisiopatología , Implantación de Prótesis de Válvulas Cardíacas/instrumentación , Implantación de Prótesis de Válvulas Cardíacas/efectos adversos , Femenino , Ecocardiografía Transesofágica , Ecocardiografía Doppler en Color , Diseño de Prótesis , Prótesis Valvulares Cardíacas , Persona de Mediana Edad , Masculino
9.
Inorg Chem ; 63(3): 1607-1612, 2024 Jan 22.
Artículo en Inglés | MEDLINE | ID: mdl-38194295

RESUMEN

Solid base catalysts are widely used in the chemical industry owing to their advantages of environmental friendliness and easy separation. However, their application is limited by basic site aggregation and poor stability. In this study, we report the preparation of magnesium (Mg) single-atom catalysts with high activity and stability by a sublimation-trapping strategy. The Mg net was sublimated as Mg vapor at 620 °C, subsequently transported through argon, and finally trapped on the defects of nitrogen-doped carbon derived from metal-organic framework ZIF-8, producing Mg1/NC. Because of the atomically dispersed Mg sites, the obtained Mg1/NC exhibits high catalytic activity and stability for Knoevenagel condensation of benzaldehyde with malononitrile, which is a typical base-catalyzed reaction. The Mg1/NC catalyst achieves a high efficiency with a turnover frequency of 49.6 h-1, which is much better than that of the traditional counterpart MgO/NC (7.7 h-1). In particular, the activity of Mg1/NC shows no decrease after five catalytic cycles, while that of MgO/NC declines due to the instability of basic sites.

10.
Inorg Chem ; 63(18): 8312-8319, 2024 May 06.
Artículo en Inglés | MEDLINE | ID: mdl-38651966

RESUMEN

Due to their maximum atomic use of metal sites, single-atom catalysts (SACs) exhibit excellent catalytic activity in a variety of reactions. Although many techniques have been reported for the production of SACs, the construction of single atoms through a convenient strategy is still challenging. Here, we provide a facile method to prepare nickel SACs by utilizing the inherent confined space between the template and silica walls in template-occupied mesoporous silica KIT-6 (TOK). After the introduction of nickel-containing precursors into the inherent confined space of the TOK by solid-phase grinding, Ni SACs can be produced promptly during calcination. Single Ni atoms create a covalent Ni-O-Si structure in the TOK, as indicated by density functional theory (DFT) calculations and experimental data. This synthetic approach is easy to scale up, and 10 g of sample can be effortlessly synthesized using ball milling. The resultant Ni SACs were applied to the oxygen evolution reaction and exhibited higher catalytic activity and stability than the comparative sample synthesized in the absence of confined space.

11.
J Chem Phys ; 160(3)2024 Jan 21.
Artículo en Inglés | MEDLINE | ID: mdl-38235798

RESUMEN

MnBi2Te4 can generate a variety of exotic topological quantum states, which are closely related to its special structure. We conduct comprehensive multiple-cycle high-pressure research on MnBi2Te4 by using a diamond anvil cell to study its phase transition behaviors under high pressure. As observed, when the pressure does not exceed 15 GPa, the material undergoes an irreversible metal-semiconductor-metal transition, whereas when the pressure exceeds 17 GPa, the layered structure is damaged and becomes irreversibly amorphous due to the lattice distortion caused by compression, but it is not completely amorphous, which presents some nano-sized grains after decompression. Our investigation vividly reveals the phase transition behaviors of MnBi2Te4 under high pressure cycling and paves the experimental way to find topological phases under high pressure.

12.
Proc Natl Acad Sci U S A ; 118(14)2021 04 06.
Artículo en Inglés | MEDLINE | ID: mdl-33785600

RESUMEN

The contraction of heart cells is controlled by the intermolecular signaling between L-type Ca2+ channels (LCCs) and ryanodine receptors (RyRs), and the nanodistance between them depends on the interaction between junctophilin-2 (JPH2) in the sarcoplasmic reticulum (SR) and caveolin-3 (CAV3) in the transversal tubule (TT). In heart failure, decreased expression of JPH2 compromises LCC-RyR communication leading to deficient blood-pumping power. In the present study, we found that JPH2 and CAV3 transcription was concurrently regulated by serum response factor (SRF) and myocardin. In cardiomyocytes from torpid ground squirrels, compared with those from euthermic counterparts, myocardin expression was up-regulated, which boosted both JPH2 and CAV3 expression. Transmission electron microscopic imaging showed that the physical coupling between TTs and SRs was tightened during hibernation and after myocardin overexpression. Confocal Ca2+ imaging under the whole-cell patch clamp condition revealed that these changes enhanced the efficiency of LCC-RyR intermolecular signaling and fully compensated the adaptive down-regulation of LCCs, maintaining the power of heart contraction while avoiding the risk of calcium overload during hibernation. Our finding not only revealed an essential molecular mechanism underlying the survival of hibernating mammals, but also demonstrated a "reverse model of heart failure" at the molecular level, suggesting a strategy for treating heart diseases.


Asunto(s)
Señalización del Calcio , Hibernación , Miocitos Cardíacos/metabolismo , Animales , Caveolinas/genética , Caveolinas/metabolismo , Células Cultivadas , Acoplamiento Excitación-Contracción , Proteínas de la Membrana/genética , Proteínas de la Membrana/metabolismo , Proteínas Nucleares/sangre , Proteínas Nucleares/metabolismo , Sciuridae , Transactivadores/sangre , Transactivadores/metabolismo
13.
Nano Lett ; 23(23): 11226-11232, 2023 Dec 13.
Artículo en Inglés | MEDLINE | ID: mdl-37972313

RESUMEN

The emergence of two-dimensional (2D) van der Waals (vdW) magnets provides a broad platform for studying the magnetic properties of low-dimensional materials in condensed matter physics. However, the intrinsic ferromagnetism of 2D materials is mostly observed below room temperature, and most of them are soft ferromagnetic materials. Here, we report two intrinsic ferromagnetic vdW materials with Curie temperatures (TC) above room temperature, MnSiTe3 (TC ∼ 378 K) and MnGeTe3 (TC ∼ 349 K). Moreover, MnSiTe3 exhibits a large coercivity (HC) at room temperature with an unprecedented HC of 1450 Oe, which is an increase of nearly 500% compared to the reported room-temperature vdW ferromagnets. The discovery of these two materials fills the gap of vdW room-temperature hard ferromagnets, providing a broad platform and possibilities for future research on low-dimensional spin electronic device applications.

14.
Int J Mol Sci ; 25(3)2024 Jan 30.
Artículo en Inglés | MEDLINE | ID: mdl-38338959

RESUMEN

Hydropericardium hepatitis syndrome (HHS) is primarily caused by fowl adenovirus serotype 4 (FAdV-4), causing high mortality in chickens. Although vaccination strategies against FAdV-4 have been adopted, HHS still occurs sporadically. Furthermore, no effective drugs are available for controlling FAdV-4 infection. However, type I and III interferon (IFN) are crucial therapeutic agents against viral infection. The following experiments were conducted to investigate the inhibitory effect of chicken IFN against FadV-4. We expressed recombinant chicken type I IFN-α (ChIFN-α) and type III IFN-λ (ChIFN-λ) in Escherichia coli and systemically investigated their antiviral activity against FAdV-4 infection in Leghorn male hepatocellular (LMH) cells. ChIFN-α and ChIFN-λ dose dependently inhibited FAdV-4 replication in LMH cells. Compared with ChIFN-λ, ChIFN-α more significantly inhibited viral genome transcription but less significantly suppressed FAdV-4 release. ChIFN-α- and ChIFN-λ-induced IFN-stimulated gene (ISG) expression, such as PKR, ZAP, IRF7, MX1, Viperin, IFIT5, OASL, and IFI6, in LMH cells; however, ChIFN-α induced a stronger expression level than ChIFN-λ. Thus, our data revealed that ChIFN-α and ChIFN-λ might trigger different ISG expression levels, inhibiting FAdV-4 replication via different steps of the FAdV-4 lifecycle, which furthers the potential applications of IFN antiviral drugs in chickens.


Asunto(s)
Carcinoma Hepatocelular , Neoplasias Hepáticas , Enfermedades de las Aves de Corral , Animales , Masculino , Pollos , Interferón-alfa/farmacología , Interferón-alfa/genética , Serogrupo , Adenoviridae/genética , Antivirales/farmacología , Enfermedades de las Aves de Corral/tratamiento farmacológico
15.
Angew Chem Int Ed Engl ; : e202408247, 2024 Jun 05.
Artículo en Inglés | MEDLINE | ID: mdl-38837719

RESUMEN

The construction of mechanically responsive materials with reversible shape-shifting, shape-locking, and stretchability holds promise for a wide range of applications in fields such as soft robotics and flexible electronics. Here, we report novel thermoelastic one-dimensional organic-inorganic hybrids (R/S-Hmpy)PbI3 (Hmpy = 2-hydroxymethyl-pyrrolidinium) to show mechanical responses. The single crystals undergo two phase transitions at 310 K and 380 K. When heated to 380 K, they show shape-shifting and expansion along the b-axis by about 13.4%, corresponding to a larger deformation than that of thermally activated shape memory alloys (8.5%), and exhibit a strong actuation force. During cooling process, the stretched crystal shape maintains and a shape-locking phenomenon occurs, which is lifted when the temperature decreasing to 305 K. Meanwhile, due to the introduction of chiral ions, the thermal switching shows a 10-fold second-order nonlinear switching contrast (common values typically below 3-fold). This study presents a thermoelastic actuator based on shape-shifting and -locking of organic-inorganic hybrids for the first time. The dielectric and nonlinear optical switching properties of organic-inorganic hybrids broaden the range of applications of mechanically responsive crystals.

16.
Ann Surg ; 277(4): 557-564, 2023 04 01.
Artículo en Inglés | MEDLINE | ID: mdl-36538627

RESUMEN

OBJECTIVE: To compare neoadjuvant chemotherapy (nCT) with CAPOX alone versus neoadjuvant chemoradiotherapy (nCRT) with capecitabine in locally advanced rectal cancer (LARC) with uninvolved mesorectal fascia (MRF). BACKGROUND DATA: nCRT is associated with higher surgical complications, worse long-term functional outcomes, and questionable survival benefits. Comparatively, nCT alone seems a promising alternative treatment in lower-risk LARC patients with uninvolved MRF. METHODS: Patients between June 2014 and October 2020 with LARC within 12 cm from the anal verge and uninvolved MRF were randomly assigned to nCT group with 4 cycles of CAPOX (Oxaliplatin 130 mg/m2 IV day 1 and Capecitabine 1000 mg/m2 twice daily for 14 d. Repeat every 3 wk) or nCRT group with Capecitabine 825 mg/m² twice daily administered orally and concurrently with radiation therapy (50 Gy/25 fractions) for 5 days per week. The primary end point is local-regional recurrence-free survival. Here we reported the results of secondary end points: histopathologic response, surgical events, and toxicity. RESULTS: Of the 663 initially enrolled patients, 589 received the allocated treatment (nCT, n=300; nCRT, n=289). Pathologic complete response rate was 11.0% (95% CI, 7.8-15.3%) in the nCT arm and 13.8% (95% CI, 10.1-18.5%) in the nCRT arm ( P =0.33). The downstaging (ypStage 0 to 1) rate was 40.8% (95% CI, 35.1-46.7%) in the nCT arm and 45.6% (95% CI, 39.7-51.7%) in the nCRT arm ( P =0.27). nCT was associated with lower perioperative distant metastases rate (0.7% vs. 3.1%, P =0.03) and preventive ileostomy rate (52.2% vs. 63.6%, P =0.008) compared with nCRT. Four patients in the nCT arm received salvage nCRT because of local disease progression after nCT. Two patients in the nCT arm and 5 in the nCRT arm achieved complete clinical response and were treated with a nonsurgical approach. Similar results were observed in subgroup analysis. CONCLUSIONS: nCT achieved similar pCR and downstaging rates with lower incidence of perioperative distant metastasis and preventive ileostomy compared with nCRT. CAPOX could be an effective alternative to neoadjuvant therapy in LARC with uninvolved MRF. Long-term follow-up is needed to confirm these results.


Asunto(s)
Terapia Neoadyuvante , Neoplasias del Recto , Humanos , Terapia Neoadyuvante/métodos , Resultado del Tratamiento , Capecitabina/uso terapéutico , Neoplasias del Recto/patología , Quimioradioterapia/métodos , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Estadificación de Neoplasias
17.
Anal Chem ; 95(44): 16201-16209, 2023 Nov 07.
Artículo en Inglés | MEDLINE | ID: mdl-37878758

RESUMEN

Circular dichroism (CD) spectroscopy is a well-known and powerful technique widely used for distinguishing chiral enantiomers based on their differential absorbance of the right and left circularly polarized light. With the increasing demand for solid-state chiral optics, CD spectroscopy has been extended to elucidate the chirality of solid-state samples beyond the traditional solution state. However, due to the sample preparation differential, the CD spectra of the same compound measured by different researchers may not be mutually consistent. In this study, we employ solution, powder, thin-film, and single-crystal samples to explore the challenges associated with CD measurements and distinguish between genuine and fake signals. Rational fabrication of the solid-state samples can effectively minimize the macroscopic anisotropic nature of the samples and thereby mitigate the influence of linear dichroism (LD) and linear birefringence (LB) effects, which arise from anisotropy-induced differences in the absorbances and refractive indices. The local anisotropic and overall isotropic features of the high-quality thin-film sample achieve an optically isotropic state, which exhibits superior CD signal repeatability at the front and back sides at different angles by rotating the sample along the light path. In addition, sample thickness-induced CD signal overload and absorption saturation pose more severe challenges than the LBLD-induced amplified CD signal but are rarely focused on. The CD signal overload in the deep UV region leads to the presence of fake signals, while absorption saturation results in a complete loss of the CD signal. These findings help obtain accurate CD signals by a well-fabricated optically isotropic sample to avoid LDLB and optimize the sample thickness to avoid fake signals and no signals.

18.
Small ; 19(35): e2300467, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37127871

RESUMEN

Ni(OH)2 nanosheet, acting as a potential active material for supercapacitors, commonly suffers from sluggish reaction kinetics and low intrinsic conductivity, which results in suboptimal energy density and long cycle life. Herein, a convenient electrochemical halogen functionalization strategy is applied for the preparation of mono/bihalogen engineered Ni(OH)2 electrode materials. The theoretical calculations and experimental results found that thanks to the extraordinarily high electronegativity, optimal reversibility, electronic conductivity, and reaction kinetics could be achieved through F functionalization . However, benefiting from the largest ionic radius, INi(OH)2 contributes the best specific capacity and morphology transformation, which is a new finding that distinguishes it from previous reports in the literature. The exploration of the interaction effect of halogens (F, INi(OH)2 , F, BrNi(OH)2 , and Cl, INi(OH)2 ) manifests that F, INi(OH)2 delivers a higher specific capacity of 200.6 mAh g-1 and an excellent rate capability of 58.2% due to the weaker electrostatic repulsion, abundant defect structure, and large layer spacing. Moreover, the F, INi(OH)2 //FeOOH@NrGO device achieves a high energy density of 97.4 Wh kg-1 and an extremely high power density of 32426.7 W kg-1 , as well as good cycling stability. This work develops a pioneering tactic for designing energy storage materials to meet various demands.

19.
J Transl Med ; 21(1): 538, 2023 08 12.
Artículo en Inglés | MEDLINE | ID: mdl-37573314

RESUMEN

BACKGROUND: Limited research has been conducted on the potential relationship between the dietary inflammation index (DII) and mortality, particularly in individuals with Helicobacter pylori (H. pylori) infection. This study aimed to investigate the association between the DII and H. pylori infection, as well as their respective impacts on all-cause mortality in a cohort of individuals with or without H. pylori infection. METHODS: Data from the 1999-2018 National Health and Nutrition Examination Survey (NHANES) were utilized for this study, with a final of 4370 participants included. Both univariable and multivariable-adjusted logistic regression analyses were employed to explore the relationship between H. pylori infection and pertinent covariates. Cox regression analysis, as well as restricted regression cubic spline analysis, were utilized to assess the association between DII and all-cause mortality among individuals with or without H. pylori infection. RESULTS: The findings demonstrated a positive correlation between DII scores and H. pylori infection, even after adjusting for potential confounding factors. Moreover, higher DII scores were significantly associated with an elevated risk of mortality exclusively in individuals with H. pylori infection, while no such association was observed in the uninfected population. Additional analysis using restricted cubic spline modeling revealed a positive linear relationship between DII scores as a continuous variable and the adjusted risk of all-cause mortality specifically in H. pylori-infected patients. CONCLUSION: The results of this study indicated that DII was positively correlated with an increased risk of H. pylori infection and was associated with a heightened risk of all-cause mortality solely in individuals with H. pylori infection. Consequently, DII might serve as a useful tool for risk stratification in the H. pylori-infected population among U.S. adults. Further research is warranted to elucidate the underlying mechanisms and potential clinical implications of these findings.


Asunto(s)
Infecciones por Helicobacter , Helicobacter pylori , Adulto , Humanos , Encuestas Nutricionales , Infecciones por Helicobacter/complicaciones , Infecciones por Helicobacter/epidemiología , Dieta/efectos adversos , Inflamación
20.
Phys Rev Lett ; 131(16): 166703, 2023 Oct 20.
Artículo en Inglés | MEDLINE | ID: mdl-37925723

RESUMEN

Finding tunable van der Waals (vdW) ferromagnets that operate at above room temperature is an important research focus in physics and materials science. Most vdW magnets are only intrinsically magnetic far below room temperature and magnetism with square-shaped hysteresis at room temperature has yet to be observed. Here, we report magnetism in a quasi-2D magnet Cr_{1.2}Te_{2} observed at room temperature (290 K). This magnetism was tuned via a protonic gate with an electron doping concentration up to 3.8×10^{21} cm^{-3}. We observed nonmonotonic evolutions in both coercivity and anomalous Hall resistivity. Under increased electron doping, the coercivities and anomalous Hall effects (AHEs) vanished, indicating a doping-induced magnetic phase transition. This occurred up to room temperature. DFT calculations showed the formation of an antiferromagnetic (AFM) phase caused by the intercalation of protons which induced significant electron doping in the Cr_{1.2}Te_{2}. The tunability of the magnetic properties and phase in room temperature magnetic vdW Cr_{1.2}Te_{2} is a significant step towards practical spintronic devices.

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