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1.
Angew Chem Int Ed Engl ; : e202409484, 2024 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-39218790

RESUMEN

Utilizing hot carriers for efficient plasmonic-mediated chemical reactions (PMCRs) to convert solar energy into secondary energy is one of the most feasible solutions to the global environmental and energy crisis. Finding a plasmonic heterogeneous nanostructure with a more efficient and reasonable hot carrier transport path without affecting the intrinsic plasmonic properties is still a major challenge that urgently needs to be solved in this field. Herein, the mechanism by which plasmonic-promoted interatomic hot electron redistribution on the surface of Au3Cu alloy nanoparticles promotes the electrocatalytic nitrogen reduction reaction (ENRR) is successfully clarified. The localized surface plasmon resonance (LSPR) effect can boost the transfer of plasmonic hot electrons from Au atoms to Cu atoms, trigger the interatomic electron regulation of Au3Cu alloy nanoparticles, enhance the desorption of ammonia molecules, and increase the ammonia yield by approximately 93.9%. This work provides an important reference for rationally designing and utilizing the LSPR effect to efficiently regulate the distribution and mechanism of plasmonic hot carriers on the surface of heterogeneous alloy nanostructures.

2.
J Phys Chem A ; 128(36): 7536-7545, 2024 Sep 12.
Artículo en Inglés | MEDLINE | ID: mdl-39194318

RESUMEN

Graphyne has attracted considerable interest and attention since its successful synthesis, due to its enormous potential for applications in the fields of electronics, energy, catalysis, information technology, etc. Although various methods for synthesizing graphyne have been explored, single-layer graphynes have not been successfully developed. Hexaethynylbenzene (HEB) is considered an ideal precursor molecule because it can undergo Glaser coupling reactions between molecules to synthesize single layer graphdiyne on single crystal metal surfaces via on-surface reactions. Unfortunately, this method fails to achieve the expected results, and the underlying mechanism is not clear. In this work, we employed a combination of ab initio molecular dynamics (AIMD) and quantum mechanics (QM) methods to investigate the initial reaction mechanism of HEB molecules on a Au(111) surface. We revealed that HEB molecules undergo both intermolecular coupling and intramolecular cyclization on the Au(111) surface. The favorable pathways of these two types of reactions were then distinguished, confirming that the distance between the terminal carbon atoms of the ethynyl groups plays an important role in C-C coupling. The insights revealed from this work could facilitate the rational design of precursor molecules and deepen the understanding of the reaction processes.

3.
ACS Appl Mater Interfaces ; 16(36): 47581-47589, 2024 Sep 11.
Artículo en Inglés | MEDLINE | ID: mdl-39207535

RESUMEN

High-voltage Li metal batteries (LMBs) based on ether electrolytes hold potential for achieving high energy densities exceeding 500 Wh kg-1, but face challenges with electrolyte oxidative stability, particularly concerning aluminum (Al) current collector corrosion. However, the specific chemistry behind Al corrosion and its effect on electrolyte components remains unexplored. Here, our study delves into Al corrosion in the representative LiFSI-DME electrolyte system, revealing that low-concentration electrolytes exacerbate Al current collector corrosion and solvent decomposition. In contrast, high-concentration electrolytes mitigate these issues, enhancing long-term stability. Remarkably, LiFSI-0.7DME electrolyte demonstrates exceptional stability with up to 1000 cycles at high voltage without significant capacity decay. These findings offer crucial insights into Al corrosion mechanisms in ether-based electrolytes, advancing our comprehension of high-voltage LMBs and facilitating their development for practical applications.

4.
Adv Mater ; : e2405115, 2024 Aug 13.
Artículo en Inglés | MEDLINE | ID: mdl-39136124

RESUMEN

Circuits based on organic electrochemical transistors (OECTs) have great potential in the fields of biosensors and artificial neural computation due to their biocompatibility and neural similarity. However, the integration of OECT-based circuits lags far behind other emerging electronics. Here, ternary inverters based on antiambipolar vertical OECTs (vOECTs) and their integration with the establishment of neural networks are demonstrated. Specifically, by adopting a small molecule (t-gdiPDI) as the channel of vOECT, high antiambipolar performance, with current density of 33.9 ± 2.1 A cm-2 under drain voltage of 0.1 V, peak voltage ≈0 V, low driving voltage < ± 0.6 V, and current on/off ratio > 106, are realized. Consequently, vertically stacked ternary circuits based solely on OECTs are constructed for the first time, showing three distinct logical states and high integration density. By further developing inverter array as the internal fundamental units of ternary weight network hardware circuits for ternary processing and computation, it demonstrates excellent data classification and recognition capabilities. This work demonstrates the possibility of constructing multi-valued logic circuits by OECTs and promotes a new strategy for high-density integration and multivalued computing systems based on organic circuits.

5.
PLoS One ; 19(7): e0305351, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38980852

RESUMEN

Due to the influence of coal rock shape, hardness, working environment and other factors in the cutting process of cantilever roadheader, the cutting head will produce irregular and violent vibration. As the rotary table of key stress components, its operation process stability, dynamic reliability and life affect the cutting efficiency and cutting stability of cantilever roadheader. In order to study the vibration characteristics of the rotary table in the cutting process, firstly, based on the theory of spatial force analysis and calculation, the spatial mechanical model of the rotary table of the cantilever roadheader is established. By solving the balance equation of the rotary table force system, the variation law of the load at the hinge ear of the rotary table with the cutting pitch angle and the horizontal angle is obtained. Secondly, based on the path transfer analysis method of working condition, the vibration data of cutting head, cutting cantilever, cutting lifting and rotary hydraulic cylinder under stable cutting condition are taken as input signals. By constructing the transfer path analysis model of rotary table working condition, the synthetic vibration of rotary table in cutting process is simulated, and the main vibration source of rotary table is determined. Then, the vibration contribution and contribution degree of each vibration excitation point to the hinge ear of rotary table are studied. By building a cutting test bench, the vibration response of rotary table in cutting process is tested to verify the correctness of the theoretical model.Thirdly, based on the frequency domain analysis method of random vibration fatigue life, combined with the S-N curve of the rotary table, the PSD curve at the maximum stress of the rotary table is obtained by modal excitation method, and the load data is imported into ANSYS nCode software to obtain the life cloud diagram and damage cloud diagram of the rotary table, and then the fatigue life of the rotary table under symmetrical cyclic load is solved. Finally, based on the response surface optimization analysis method, the maximum stress and maximum deformation of the rotary table are taken as the optimization objectives, and the aperture of each hinge ear of the rotary table is taken as the optimization variable. Based on Design Expert, a second-order regression model is established to realize the multi-objective optimization design of the key stress parts of the rotary table in the cutting process. The simulation results show that under the same cutting conditions, the maximum stress of the optimized rotary table is reduced by 15.82% year-on-year, and the maximum deformation is reduced by 24.70% year-on-year. The optimized rotary table structure can better adapt to the cutting process, which is beneficial to improve the service life of the rotary table and enhance its operation stability. The research results are beneficial to enrich the relevant research theory in the field of rotary table vibration of cantilever roadheader, and are beneficial to improve the service life of the rotary table and the efficiency of tunneling and mining.


Asunto(s)
Diseño de Equipo , Vibración , Modelos Teóricos
6.
Angew Chem Int Ed Engl ; : e202411722, 2024 Jul 30.
Artículo en Inglés | MEDLINE | ID: mdl-39081066

RESUMEN

Thermally-induced dehydrogenative coupling of polyphenylenes on metal surfaces is an important technique to synthesize 𝜋-conjugated carbon nanostructures with atomic precision. However, this protocol has rarely been utilized to fabricate structurally defined carbon nanosheets composed of sp- and sp2-hybridized carbon atoms. Here, we present the synthesis of butadiyne-linked hexabenzocoronenes (HBCs) on Au(111) surfaces as core-expanded graphdiynes. The reaction started from hexa(4-ethylphenyl)benzene, which undergoes dehydrogenation toward hexa(4-vinylphenyl)benzene, followed by planarization to hexabenzocoronene, coupling between the vinyl groups, and further dehydrogenation. In addition to butadiyne linkages, benzene groups were also found as another type of linker. The reaction sequences were monitored by scanning tunneling microscopy and bond-resolved non-contact atomic force microscopy, which disclose the structures of intermediates and final products. In combination with density functional theory simulations, the key steps from ethyl substituents to butadiyne and benzene linkers were elucidated. This is a new on-surface synthesis of core-expanded graphdiynes with unprecedented electronic properties.

7.
Adv Mater ; 36(33): e2403935, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38889294

RESUMEN

Tissue-specific delivery of oligonucleotide therapeutics beyond the liver remains a key challenge in nucleic acid drug development. To address this issue, exploiting exosomes as a novel carrier has emerged as a promising approach for efficient nucleic acid drug delivery. However, current exosome-based delivery systems still face multiple hurdles in their clinical applications. Herein, this work presents a strategy for constructing a hybrid exosome vehicle (HEV) through a DNA zipper-mediated membrane fusion approach for tissue-specific siRNA delivery. As a proof-of-concept, this work successfully fuses a liposome encapsulating anti-NFKBIZ siRNAs with corneal epithelium cell (CEC)-derived exosomes to form a HEV construct for the treatment of dry eye disease (DED). With homing characteristics inherited from exosomes, the siRNA-bearing HEV can target its parent cells and efficiently deliver the siRNA payloads to the cornea. Subsequently, the NFKBIZ gene silencing significantly reduces pro-inflammatory cytokine secretions from the ocular surface, reshapes its inflammatory microenvironment, and ultimately achieves an excellent therapeutic outcome in a DED mouse model. As a versatile platform, this hybrid exosome with targeting capability and designed therapeutic siRNAs may hold great potential in various disease treatments.


Asunto(s)
Exosomas , Liposomas , Fusión de Membrana , ARN Interferente Pequeño , Exosomas/metabolismo , Exosomas/química , ARN Interferente Pequeño/metabolismo , Animales , Ratones , Liposomas/química , Síndromes de Ojo Seco/terapia , Humanos , Epitelio Corneal/metabolismo , Epitelio Corneal/patología , Silenciador del Gen , Córnea/metabolismo
8.
Ann Med Surg (Lond) ; 86(5): 3117-3122, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38694365

RESUMEN

Introduction: Appendiceal signet-ring cell adenocarcinoma (ASCA) is rare and more aggressive in malignant appendiceal neoplasms. The presentation can be appendicitis, which is lack of specific symptom and makes early diagnosis difficult. There is no effective surveillance. Prognosis largely relies on timely detection. We report a case of ASCA incidentally diagnosed through pathological examination after appendectomy for appendicitis. Case presentation: The patient presented to our department with a progressive right lower quadrant abdominal pain lasting for 3 days. Physical examination revealed rigidity, tenderness, and rebound tenderness on the right lower quadrant. A computed tomography scan showed a thickened, inflamed appendix with peri-appendiceal fat stranding without noticeable appendiceal mass at initial evaluation. The diagnosis was considered acute appendicitis, and an appendectomy was performed. The appendix was inflamed, gangrenous and perforated, and no mass was found during the surgery. Surgical specimen was sent for physiological examination, which incidentally detected signet-ring cell in H&E staining. And immunohistochemistry confirmed the diagnosis of ASCA with small amount of neuroendocrine neoplasms. Conclusion: Early diagnosis of ASCA can incidentally be made on pathological specimen following appendectomy for appendicitis. A routine pathological examination should be emphasized, and appendectomy may not be the endpoint of the treatment. Hemicolectomy and adjuvant therapy might ensue upon the diagnosis of appendiceal neoplasm. The poor prognosis of ASCA makes a timely diagnosis significant. Basic research is promising to unravel the molecular mechanisms of pathogenesis, finding typical tumor markers for screening and novel effective therapies for advanced cases.

9.
Sci Rep ; 14(1): 10048, 2024 May 02.
Artículo en Inglés | MEDLINE | ID: mdl-38698118

RESUMEN

As one of the key components of the belt conveyor, the roller bears the task of supporting and rolling the conveyor belt, and monitoring its condition is very important. The traditional monitoring of the conveyor roller group adopts worker inspection, which has strong subjectivity. Monitoring using sensors necessitates the use of numerous sensors, which can pose wiring challenges. The use of inspection robots for monitoring results can be discontinuous, and their performance may be limited. This study proposes a fault diagnosis method for rollers based on a distributed fiber optic sensing system. By improving the traditional Isolation Forest (IForest), a framework called Incremental Majority Voting Isolation Forest (IMV-IForest) is proposed. By analyzing the optical signal, we extracted the variation patterns of roller faults over time and space, and analyzed the abnormal score distribution between fault data and normal data. Using the dataset collected on-site, we compared and analyzed IMV-IForest with the traditional IForest and the Extended Isolation Forest (E-iForest). The results indicate that the variation of the fault of the faulty roller with time and space can be used for early prediction of roller faults; determine an anomaly score threshold of 0.6; improved IForest have faster computation time and higher accuracy. Finally, to verify the effectiveness of the proposed scheme, a 3-month experiment was conducted on a 600 m long belt conveyor in a certain mine, and on-site monitoring results were obtained. By comparing with manual detection results, it was shown that the proposed method has high recognition rate for faulty idlers, with an accuracy rate of 97.92%, and can effectively diagnose faulty idlers.

10.
PLoS One ; 19(3): e0299805, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38512903

RESUMEN

The automatic cutting of coal and rock surface morphology modeling based on the actual geological environment of coal mine underground excavation and mining is of great significance for improving the surface quality of coal and rock after cutting and enhancing the safety and stability of advanced support. To this end, using the principle of coordinate transformation, the kinematic trajectory of the cutting head of the tunneling machine is established, and the contour morphology of the cutting head under variable cutting technology is obtained. Then, based on the regenerative vibration theory of the cutting head, a dynamic model of the cutting head coal wall is established, and the coordinate relationship of the cutting head in the tunnel coordinate system under vibration induction is analyzed. Based on fractal theory and Z-MAP method, a simulation method for the surface morphology of coal and rock after cutting is proposed, which is driven by the cutting trajectory Under the coupling effect of cutting vibration induction and random fragmentation of coal and rock, simulation of the surface morphology of comprehensive excavation tunnels was conducted, and relevant experiments were conducted to verify the results. A 1:3 similarity experimental model of EBZ160 tunneling machine was used to build a cutting head coal and rock system cutting experimental platform for comparative experiments of cutting morphology. Furthermore, statistical methods were used to compare and evaluate the simulated roof with the actual roof. The results show that the relative errors between the maximum range of peaks and valleys, the peak skewness coefficient of height standard deviation, and the kurtosis coefficient of the actual roof are 1.3%, 24.5%, 16%, and 2.9%, respectively. Overall, this indicates that the surface morphology distribution characteristics of the simulated roof and the actual roof are similar, verifying the effectiveness of the modeling and simulation method proposed in this paper, and providing theoretical support for the design and optimization of advanced support in the future.


Asunto(s)
Carbón Mineral , Traumatismos Craneocerebrales , Humanos , Simulación por Computador , Ambiente , Fractales
11.
Angew Chem Int Ed Engl ; 63(18): e202401773, 2024 Apr 24.
Artículo en Inglés | MEDLINE | ID: mdl-38429971

RESUMEN

Organic electrochemical transistors (OECTs) rely on both efficient ionic doping/de-doping process and carrier transport in the mixed ionic-electronic channel under the modulation of gate bias. Moreover, channels that hold photopatterning capability are highly desired to minimize parasitic capacitance and simplify the fabrication process/cost. However, yielding photo-patternable channels with both precise/robust patterning capability and controllable ionic-electronic coupling is still challenging. Herein, double-end trifluoromethyl diazirines (DtFDA) with different chain lengths are introduced in the OECT channel to act as both photo-crosslinker and medium to regulate ionic-electronic transport. Specifically, high-resolution patterns with a minimum line width/gap of 2 µm are realized in p(g2T-T) or Homo-gDPP based channels by introducing DtFDA. Maximum transconductances of 68.6 mS and 81.6 mS, current on/off ratio of 106 and 107 (under a drain voltage of only ±0.1 V), are achieved in p- and n-type vertical OECTs (vOECTs), respectively, along with current densities exceeding 1 kA cm-2 and good cycling stability of more than 100,000 cycles (2000 seconds). This work provides a new and facile strategy for the fabrication of vOECT channels with high resolution and high performance via the introduction of a simple and efficient crosslinker.

12.
Adv Mater ; 36(19): e2311424, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38325426

RESUMEN

Apart from Li4Ti5O12, there are few anode substitutes that can be used in commercial high-power lithium-ion batteries. Orthorhombic T-Nb2O5 has recently been proven to be another substitute anode. However, monoclinic B-Nb2O5 of same chemistry is essentially inert for lithium storage, but the underlying reasons are unclear. In order to activate the "inert" B-Nb2O5, herein, nanoporous pseudocrystals to achieve a larger specific capacity of 243 mAh g-1 than Li4Ti5O12 (theoretical capacity: 175 mAh g-1) are proposed. These pseudocrystals are rationally synthesized via a "shape-keep" topological microcorrosion process from LiNbO3 precursor. Compared to pristine B-Nb2O5, experimental investigations reveal that B-Nb2O5- x delivers ≈3000 times higher electronic conductivity and tenfold enhanced Li+ diffusion coefficient. An ≈30% reduction of energy barrier for Li-ion migration is also confirmed by the theoretical calculations. The nanoporous B-Nb2O5- x delivers unique ion/electron transport channels to proliferate the reversible and deeper lithiation, which activate the "inert" B-Nb2O5. The capacitive-like behavior is observed to endow B-Nb2O5- x ultrafast lithium storage ability, harvesting 136 mAh g-1 at 100 C and 72 mAh g-1 even at 250 C, superior to Li4Ti5O12. Pouch-type full cells exhibit the energy density of ≈251 Wh kg-1 and ultrahigh power density up to ≈35 kW kg-1.

13.
Ann Med Surg (Lond) ; 86(2): 1152-1155, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38333290

RESUMEN

Introduction and importance: Abdominal cocoon syndrome (ACS), as a rare cause of mechanical intestinal obstruction, can be divided into primary/idiopathic vs. secondary type. The primary ACS is often asymptomatic and only diagnosed in exploratory laparotomy. The major treatment of surgery can be challenging. Since the gut wall and peritoneum are densely adhered, gut perforation might occur during adhesiolysis. Thus, it is important to have an experienced surgeon to perform the surgery. Case presentation: The authors present a primary ACS case of a 50-year-old man. The patient demonstrated an unbearable upper abdominal pain upon admission. A computed tomography (CT) scan showed a severe bowel obstruction. An exploratory laparotomy was indicated, leading to the diagnosis of ACS, which was considered idiopathic after ruling out secondary factors. An adhesiolysis was performed successfully. Note that the entire intestine measured was only 2.1 m during the surgery. There was no post-surgical complication. The patient was recovered uneventfully. Clinical discussion: The aetiology of primary ACS is unknown. The incidence is comparatively low and considered equal between men and women. As a rare cause of gut obstruction, the suspicion of the diagnosis should be strengthened. Surgery including adhesiolysis and bowel resection remains the major treatment. If adhesiolysis fails, bowel resection will be inevitable. The knowledge and experience of surgeon will be tested. Conclusion: The aetiology of primary ACS should be further explored. And the differential diagnosis of bowel obstruction should cover ACS in order for the surgeon to be prepared before surgery.

14.
Int J Biol Macromol ; 263(Pt 1): 130271, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38373570

RESUMEN

Overuse of insecticides has accelerated the evolution of insecticide resistance and created serious environmental concerns worldwide, thus incentivizing development of alternative methods. Bacillus thuringiensis (Bt) is an insecticidal bacterium that has been developed as a biopesticide to successfully control multiple species of pests. It operates by secreting several insect toxins such as Cry1Ac. However, metabolic resistance based on ATP-binding cassette (ABC) transporters may play a crucial role in the development of metabolic resistance to Bt. Here, we characterized an ABCG gene from the agricultural pest Plutella xylostella (PxABCG3) and found that it was highly expressed in a Cry1Ac-resistant strain, up-regulated after Cry1Ac protoxin treatment. Binding miR-8510a-3p to the coding sequence (CDS) of PxABCG3 was then confirmed by a luciferase reporter assay and RNA immunoprecipitation. miR-8510a-3p agomir delivery markedly reduced PxABCG3 expression in vivo and consequently decreased the tolerance of P. xylostella to Cry1Ac, while reduction of miR-8510a-3p significantly increased PxABCG3 expression, accompanied by an increased tolerance to Cry1Ac. Our results suggest that miR-8510a-3p could potentially be used as a novel molecular target against P. xylostella or other lepidopterans, providing novel insights into developing effective and environmentally friendly pesticides.


Asunto(s)
Bacillus thuringiensis , Insecticidas , MicroARNs , Mariposas Nocturnas , Animales , Mariposas Nocturnas/metabolismo , Larva/genética , Endotoxinas/genética , Endotoxinas/metabolismo , Toxinas de Bacillus thuringiensis/metabolismo , Bacillus thuringiensis/química , Insecticidas/farmacología , Insecticidas/metabolismo , Transportadoras de Casetes de Unión a ATP/genética , Transportadoras de Casetes de Unión a ATP/metabolismo , MicroARNs/genética , MicroARNs/metabolismo , Proteínas Hemolisinas/genética , Proteínas Hemolisinas/farmacología , Proteínas Hemolisinas/metabolismo , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo
15.
J Colloid Interface Sci ; 660: 545-554, 2024 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-38266336

RESUMEN

Thermal runaway is a hazardous risk, occurring more readily in high-energy-density lithium-ion batteries (LIBs), which leads to a rapid temperature rise and even combustion or explosion when using flammable electrolyte systems. Flame retardants (FRs), such as trimethyl phosphate (TMPa) and triethyl phosphate (TEP), are commonly utilized due to their effective flame suppression, low toxicity, and excellent thermal stability. However, the lack of in-depth understanding of the flame retardancy mechanism and solid electrolyte interphase (SEI) formation process has made the development of functional electrolytes difficult at present. In this study, we clarified the flame retardancy and interfacial reaction mechanisms of low-flammable TMPa localized high-concentration electrolytes (LHCE) using hybrid ab initio and reactive force field (HAIR) schemes. Long-term HAIR simulation reveals that phosphorous radicals produced by the decomposition of TMPa capture carbon radicals, encouraging their polymerization into low-flammable oligomers, while fluorine-containing solvents in the electrolyte capture hydrogen radicals and produce nonflammable hydrofluoric acid (HF). This synergistic flame retardancy mechanism provides essential atomic-level insights for the rational design of high-safety electrolytes in the future.

16.
Phys Chem Chem Phys ; 26(9): 7269-7275, 2024 Feb 28.
Artículo en Inglés | MEDLINE | ID: mdl-38193864

RESUMEN

On the basis of variable-temperature single-crystal X-ray diffraction, rotational energy barrier analysis, variable-temperature/frequency dielectric response, and molecular dynamics simulations, here we report a new crystalline supramolecular rotor (CH3NH3)(18-crown-6)[CuCl3], in which the (H3C-NH3)+ ion functions as a smallest dual-wheel rotator showing bisected rotation dynamics, while the host 18-crown-6 macrocycle behaves as a stator that is not strictly stationary. This study also provides a helpful insight into the dynamics of ubiquitous -CH3/-NH3 groups confined in organic or organic-inorganic hybrid solids.

17.
Adv Sci (Weinh) ; 11(13): e2306248, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38251411

RESUMEN

Protein degradation techniques, such as proteolysis-targeting chimeras (PROTACs) and lysosome-targeting chimeras (LYTACs), have emerged as promising therapeutic strategies for the treatment of diseases. However, the efficacy of current protein degradation methods still needs to be improved to address the complex mechanisms underlying diseases. Herein, a LYTAC Plus hydrogel engineered is proposed by nucleic acid self-assembly, which integrates a gene silencing motif into a LYTAC construct to enhance its therapeutic potential. As a proof-of-concept study, vascular endothelial growth factor receptor (VEGFR)-binding peptides and mannose-6 phosphate (M6P) moieties into a self-assembled nucleic acid hydrogel are introduced, enabling its LYTAC capability. Small interference RNAs (siRNAs) is then employed that target the angiopoietin-2 (ANG-2) gene as cross-linkers for hydrogel formation, giving the final LYTAC Plus hydrogel gene silencing ability. With dual functionalities, the LYTAC Plus hydrogel demonstrated effectiveness in simultaneously reducing the levels of VEGFR-2 and ANG-2 both in vitro and in vivo, as well as in improving therapeutic outcomes in treating neovascular age-related macular degeneration in a mouse model. As a general material platform, the LYTAC Plus hydrogel may possess great potential for the treatment of various diseases and warrant further investigation.


Asunto(s)
Ácidos Nucleicos , Factor A de Crecimiento Endotelial Vascular , Ratones , Animales , Factor A de Crecimiento Endotelial Vascular/genética , Regulación hacia Abajo , ARN Interferente Pequeño/genética , Hidrogeles
18.
Adv Mater ; 36(6): e2309637, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-37985136

RESUMEN

Molybdenum disulfide (MoS2 ) with high theoretical capacity is viewed as a promising anode for sodium-ion batteries but suffers from inferior rate capability owing to the polaron-induced slow charge transfer. Herein, a polaron collapse strategy induced by electron-rich insertions is proposed to effectively solve the above issue. Specifically, 1D [MoS] chains are inserted into MoS2 to break the symmetry states of 2D layers and induce small-polaron collapse to gain fast charge transfer so that the as-obtained thermodynamically stable Mo2 S3 shows metallic behavior with 107 times larger electrical conductivity than that of MoS2 . Theoretical calculations demonstrate that Mo2 S3 owns highly delocalized anions, which substantially reduce the interactions of Na-S to efficiently accelerate Na+ diffusion, endowing Mo2 S3 lower energy barrier (0.38 vs 0.65 eV of MoS2 ). The novel Mo2 S3 anode exhibits a high capacity of 510 mAh g-1 at 0.5 C and a superior high-rate stability of 217 mAh g-1 at 40 C over 15 000 cycles. Further in situ and ex situ characterizations reveal the in-depth reversible redox chemistry in Mo2 S3 . The proposed polaron collapse strategy for intrinsically facilitating charge transfer can be conducive to electrode design for fast-charging batteries.

19.
Angew Chem Int Ed Engl ; 63(4): e202315282, 2024 Jan 22.
Artículo en Inglés | MEDLINE | ID: mdl-38032360

RESUMEN

Recently, therapeutic cancer vaccines have emerged as promising candidates for cancer immunotherapy. Nevertheless, their efficacies are frequently impeded by challenges including inadequate antigen encapsulation, insufficient immune activation, and immunosuppressive tumor microenvironment. Herein, we report a three-in-one hydrogel assembled by nucleic acids (NAs) that can serve as a vaccine to in situ trigger strong immune response against cancer. Through site-specifically grafting the chemodrug, 7-ethyl-10-hydroxycamptothecin (also known as SN38), onto three component phosphorothioate (PS) DNA strands, a Y-shaped motif (Y-motif) with sticky ends is self-assembled, at one terminus of which an unmethylated cytosine-phosphate-guanine (CpG) segment is introduced as an immune agonist. Thereafter, programmed cell death ligand-1 (PD-L1) siRNA that performs as immune checkpoint inhibitor is designed as a crosslinker to assemble with the CpG- and SN38-containing Y-motif, resulting in the formation of final NA hydrogel vaccine. With three functional agents inside, the hydrogel can remarkably induce the immunogenic cell death to enhance the antigen presentation, promoting the dendritic cell maturation and effector T lymphocyte infiltration, as well as relieving the immunosuppressive tumor environment. When inoculated twice at tumor sites, the vaccine demonstrates a substantial antitumor effect in melanoma mouse model, proving its potential as a general platform for synergistic cancer immunotherapy.


Asunto(s)
Melanoma , Ácidos Nucleicos , Vacunas , Animales , Ratones , Hidrogeles/metabolismo , Ácidos Nucleicos/metabolismo , Células Dendríticas/metabolismo , Inmunoterapia , Vacunación , Microambiente Tumoral , Línea Celular Tumoral , Antígeno B7-H1/metabolismo
20.
Sci Rep ; 13(1): 19236, 2023 Nov 07.
Artículo en Inglés | MEDLINE | ID: mdl-37935750

RESUMEN

A new type of parallel operation unit for excavating and supporting anchors is proposed to address the issue of imbalanced excavation anchor ratio in coal mines. By equipping a straddle type anchoring drilling rig group, the synchronous parallel and fast operation mode for excavating and supporting anchors is achieved; Consider the problem of poor drilling stability of drill pipes in coal mines due to the coupling vibration between surrounding rock and anchoring equipment. Firstly, taking the multi drilling rig anchoring system as the research object, considering the influence of the equipment itself as an influencing factor on the vibration of the drill pipe, a dynamic model of the system is constructed using Lagrangian equations, and analytical solutions for the vibration displacement of each mass block are obtained; In order to more intuitively represent the vibration process of the drill pipe, Ansys is used to conduct modal analysis on the key components of the anchoring drilling rig system, and obtain the natural frequencies and vibration modes of each order of the key components; Using Adams to solve the rigid flexible coupling dynamic model of the anchoring drilling rig system, the vibration response laws of the drill pipe under different operating states were obtained. Secondly, Abaqus was used to simulate the drilling process of the drill pipe and obtain the vibration response law generated by the interaction between the drill pipe and the surrounding rock; The results indicate that the anchoring equipment has a greater impact on the vibration of the drill pipe, and the surrounding rock has a more stable impact on the vibration of the drill pipe. Due to the short body and large span structure of the anchoring system crossbeam expansion frame, the vibration response of the drill pipe is significantly greater than that of the retracted state of the drilling rig due to being in an unstable cantilever state when the drilling rig is extended. The theoretical reliability of the vibration response law of the drill pipe under different states has been further verified through drilling experiments of the anchoring system prototype. The relevant theories can provide a theoretical basis for the implementation of automatic anchoring technology in the anchoring system.

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