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1.
Nature ; 615(7950): 56-61, 2023 03.
Artículo en Inglés | MEDLINE | ID: mdl-36859579

RESUMEN

Correlating atomic configurations-specifically, degree of disorder (DOD)-of an amorphous solid with properties is a long-standing riddle in materials science and condensed matter physics, owing to difficulties in determining precise atomic positions in 3D structures1-5. To this end, 2D systems provide insight to the puzzle by allowing straightforward imaging of all atoms6,7. Direct imaging of amorphous monolayer carbon (AMC) grown by laser-assisted depositions has resolved atomic configurations, supporting the modern crystallite view of vitreous solids over random network theory8. Nevertheless, a causal link between atomic-scale structures and macroscopic properties remains elusive. Here we report facile tuning of DOD and electrical conductivity in AMC films by varying growth temperatures. Specifically, the pyrolysis threshold temperature is the key to growing variable-range-hopping conductive AMC with medium-range order (MRO), whereas increasing the temperature by 25 °C results in AMC losing MRO and becoming electrically insulating, with an increase in sheet resistance of 109 times. Beyond visualizing highly distorted nanocrystallites embedded in a continuous random network, atomic-resolution electron microscopy shows the absence/presence of MRO and temperature-dependent densities of nanocrystallites, two order parameters proposed to fully describe DOD. Numerical calculations establish the conductivity diagram as a function of these two parameters, directly linking microstructures to electrical properties. Our work represents an important step towards understanding the structure-property relationship of amorphous materials at the fundamental level and paves the way to electronic devices using 2D amorphous materials.

2.
Nature ; 611(7935): 271-277, 2022 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-36070797

RESUMEN

Conducting polymers (CPs) with high conductivity and solution processability have made great advances since the pioneering work on doped polyacetylene1-3, thus creating the new field of 'organic synthetic metals,4. Various high-performance CPs have been realized, which enable the applications of several organic electronic devices5,6. Nevertheless, most CPs exhibit hole-dominant (p-type) transport behaviour7,8, whereas the development of n-type analogues lags far behind and only a few exhibit metallic state, typically limited by low doping efficiency and ambient instability. Here we present a facilely synthesized highly conductive n-type polymer poly(benzodifurandione) (PBFDO). The reaction combines oxidative polymerization and in situ reductive n-doping, greatly increasing the doping efficiency, and a doping level of almost 0.9 charges per repeating unit can be achieved. The resultant polymer exhibits a breakthrough conductivity of more than 2,000 S cm-1 with excellent stability and an unexpected solution processability without extra side chains or surfactants. Furthermore, detailed investigations on PBFDO show coherent charge-transport properties and existence of metallic state. The benchmark performances in electrochemical transistors and thermoelectric generators are further demonstrated, thus paving the way for application of the n-type CPs in organic electronics.

3.
Chem Rev ; 123(12): 7421-7497, 2023 Jun 28.
Artículo en Inglés | MEDLINE | ID: mdl-37232480

RESUMEN

Polymer semiconductors composed of a carbon-based π conjugated backbone have been studied for several decades as active layers of multifarious organic electronic devices. They combine the advantages of the electrical conductivity of metals and semiconductors and the mechanical behavior of plastics, which are going to become one of the futures of modulable electronic materials. The performance of conjugated materials depends both on their chemical structures and the multilevel microstructures in solid states. Despite the great efforts that have been made, they are still far from producing a clear picture among intrinsic molecular structures, microstructures, and device performances. This review summarizes the development of polymer semiconductors in recent decades from the aspects of material design and the related synthetic strategies, multilevel microstructures, processing technologies, and functional applications. The multilevel microstructures of polymer semiconductors are especially emphasized, which plays a decisive role in determining the device performance. The discussion shows the panorama of polymer semiconductors research and sets up a bridge across chemical structures, microstructures, and finally devices performances. Finally, this review discusses the grand challenges and future opportunities for the research and development of polymer semiconductors.

4.
Small ; 20(16): e2306010, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-37884476

RESUMEN

Realizing ideal charge transport in field-effect transistors (FETs) of conjugated polymers is crucial for evaluating device performance, such as carrier mobility and practical applications of conjugated polymers. However, the current FETs using conjugated polymers as the active layers generally show certain non-ideal transport characteristics and poor stability. Here, ideal charge transport of n-type polymer FETs is achieved on flexible polyimide substrates by using an organic-inorganic hybrid double-layer dielectric. Deposited conjugated polymer films show highly ordered structures and low disorder, which are supported by grazing-incidence wide-angle X-ray scattering, near-edge X-ray absorption fine structure, and molecular dynamics simulations. Furthermore, the organic-inorganic hybrid double-layer dielectric provides low interfacial defects, leading to excellent charge transport in FETs with high electron mobility (1.49 ± 0.46 cm2 V-1 s-1) and ideal reliability factors (102 ± 7%). Fabricated polymer FETs show a self-encapsulation effect, resulting in high stability of the FET charge transport. The polymer FETs still work with high mobility above 1 cm2 V-1 s-1 after storage in air for more than 300 days. Compared with state-of-the-art conjugated polymer FETs, this work simultaneously achieves ideal charge transport and environmental stability in n-type polymer FETs, facilitating rapid device optimization of high-performance polymer electronics.

5.
Brief Bioinform ; 23(3)2022 05 13.
Artículo en Inglés | MEDLINE | ID: mdl-35419596

RESUMEN

Cellular senescence (CS), a state of permanent growth arrest, is intertwined with tumorigenesis. Due to the absence of specific markers, characterizing senescence levels and senescence-related phenotypes across cancer types remain unexplored. Here, we defined computational metrics of senescence levels as CS scores to delineate CS landscape across 33 cancer types and 29 normal tissues and explored CS-associated phenotypes by integrating multiplatform data from ~20 000 patients and ~212 000 single-cell profiles. CS scores showed cancer type-specific associations with genomic and immune characteristics and significantly predicted immunotherapy responses and patient prognosis in multiple cancers. Single-cell CS quantification revealed intra-tumor heterogeneity and activated immune microenvironment in senescent prostate cancer. Using machine learning algorithms, we identified three CS genes as potential prognostic predictors in prostate cancer and verified them by immunohistochemical assays in 72 patients. Our study provides a comprehensive framework for evaluating senescence levels and clinical relevance, gaining insights into CS roles in cancer- and senescence-related biomarker discovery.


Asunto(s)
Neoplasias de la Próstata , Microambiente Tumoral , Senescencia Celular/genética , Genómica , Humanos , Inmunoterapia , Masculino , Neoplasias de la Próstata/genética , Microambiente Tumoral/genética
6.
Chemistry ; 30(16): e202304372, 2024 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-38191767

RESUMEN

Incorporating heteroatoms can effectively modulate the molecular optoelectronic properties. However, the fundamental understanding of BN doping effects in BN-embedded polycyclic aromatic hydrocarbons (PAHs) is underexplored, lacking rational guidelines to modulate the electronic structures through BN units for advanced materials. Herein, a concise synthesis of novel B2N2-perylenes with BN doped at the bay area is achieved to systematically explore the doping effect of BN position on the photophysical properties of PAHs. The shift of BN position in B2N2-perylenes alters the π electron conjugation, aromaticity and molecular rigidness significantly, achieving substantially higher electron transition abilities than those with BN doped in the nodal plane. It is further clarified that BN position dominates the photophysical properties over BN orientation. The revealed guideline here may apply generally to novel BN-PAHs, and aid the advancement of BN-PAHs with highly-emissive performance.

7.
Appl Microbiol Biotechnol ; 108(1): 17, 2024 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-38170316

RESUMEN

Polymyxins are cationic peptide antibiotics and regarded as the "final line of defense" against multidrug-resistant bacterial infections. Meanwhile, some polymyxin-resistant strains and the corresponding resistance mechanisms have also been reported. However, the response of the polymyxin-producing strain Paenibacillus polymyxa to polymyxin stress remains unclear. The purpose of this study was to investigate the stress response of gram-positive P. polymyxa SC2 to polymyxin B and to identify functional genes involved in the stress response process. Polymyxin B treatment upregulated the expression of genes related to basal metabolism, transcriptional regulation, transport, and flagella formation and increased intracellular ROS levels, flagellar motility, and biofilm formation in P. polymyxa SC2. Adding magnesium, calcium, and iron alleviated the stress of polymyxin B on P. polymyxa SC2, furthermore, magnesium and calcium could improve the resistance of P. polymyxa SC2 to polymyxin B by promoting biofilm formation. Meanwhile, functional identification of differentially expressed genes indicated that an ABC superfamily transporter YwjA was involved in the stress response to polymyxin B of P. polymyxa SC2. This study provides an important reference for improving the resistance of P. polymyxa to polymyxins and increasing the yield of polymyxins. KEY POINTS: • Phenotypic responses of P. polymyxa to polymyxin B was performed and indicated by RNA-seq • Forming biofilm was a key strategy of P. polymyxa to alleviate polymyxin stress • ABC transporter YwjA was involved in the stress resistance of P. polymyxa to polymyxin B.


Asunto(s)
Paenibacillus polymyxa , Paenibacillus , Paenibacillus polymyxa/genética , Polimixina B/farmacología , Polimixina B/metabolismo , Paenibacillus/genética , Paenibacillus/metabolismo , Calcio/metabolismo , Magnesio , Polimixinas/farmacología
8.
Reprod Domest Anim ; 59(6): e14598, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38881434

RESUMEN

Our previous research has shown that melatonin (MLT) can reduce cryopreserved ovarian damage in mice. Yet, the molecular mechanism of MLT protection is still unclear. Some studies have shown that melatonin receptor 1 (MT1) is very important for animal reproductive system. To evaluate whether MLT exerts its protective effect on cryopreserved mice ovarian tissue via MT1, we added antagonist of MT1/MT2 (Luzindor) or antagonist of MT2 (4P-PDOT) to the freezing solution, followed by cryopreservation and thawing of ovarian tissue. The levels of total superoxide dismutase (T-SOD), catalase (CAT), nitric oxide (NO) and malondialdehyde (MDA) were detected. Besides, by using RT-PCR and Western blotting, the expression of Bcl-2, Bax and Nrf2/HO-1 signalling pathway-related proteins was detected. These findings demonstrated that compared with the melatonin group, the addition of Luzindor increased apoptosis, NO and MDA activities, decreased CAT and T-SOD activities and inhibited Nrf2/HO-1 signalling pathway. In conclusion, melatonin can play a protective role in cryopreserved ovarian tissue of mice through MT1 receptor.


Asunto(s)
Criopreservación , Melatonina , Factor 2 Relacionado con NF-E2 , Ovario , Estrés Oxidativo , Receptor de Melatonina MT1 , Transducción de Señal , Animales , Femenino , Melatonina/farmacología , Estrés Oxidativo/efectos de los fármacos , Ovario/efectos de los fármacos , Receptor de Melatonina MT1/metabolismo , Receptor de Melatonina MT1/genética , Transducción de Señal/efectos de los fármacos , Factor 2 Relacionado con NF-E2/metabolismo , Factor 2 Relacionado con NF-E2/genética , Ratones , Criopreservación/veterinaria , Triptaminas/farmacología , Apoptosis/efectos de los fármacos , Hemo Oxigenasa (Desciclizante)/metabolismo , Hemo Oxigenasa (Desciclizante)/genética , Óxido Nítrico/metabolismo , Malondialdehído/metabolismo , Proteínas de la Membrana , Hemo-Oxigenasa 1
9.
Int Orthop ; 48(3): 683-692, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-37740768

RESUMEN

PURPOSE: Total knee arthroplasty is the main method for the treatment of advanced haemophilic knee arthritis. Due to the particularity of hemophilia, the blood management plan is the focus of the perioperative period for haemophilia patients. This study aimed to investigate the clinical effect and safety of intra-articular injection of tranexamic acid in patients with haemophilia. METHODS: This is a retrospective study. According to whether tranexamic acid is used or not, patients are divided into tranexamic acid group (n=30) and non-tranexamic acid group (n=29). Total blood loss, intraoperative blood loss, complete blood count, total amount of coagulation factor VIII (FVIII) usage, coagulation biomarkers, inflammatory biomarkers, knee range of motion, knee joint function, pain status, complication rate, and patient satisfaction were assessed and compared at a mean follow-up of 16 months. RESULTS: Injecting tranexamic acid into the knee joint cavity can effectively reduce the hidden blood loss and total blood loss (P<0.001), and reduce the patient's early postoperative inflammation biomarkers, pain status, and limb swelling. Therefore, the patient can obtain a better range of motion following total knee arthroplasty. In the long run, in terms of joint function and surgical satisfaction, there are no statistically significant differences. In addition, there are no statistically significant differences between the two groups of patients in terms of the total amount of FVIII usage, length of stay, and hospitalization expenses. CONCLUSION: In patients with haemophilia, intra-articular injection of tranexamic acid during total knee arthroplasty can effectively reduce postoperative blood loss, early postoperative inflammation levels, pain and limb swelling, and enable patients to receive higher-quality rehabilitation exercises to get better joint function. Previous studies on TKA in haemophilic patients have already demonstrated the efficacy of intra-articular injections of TXA in reducing postoperative blood loss. Our study confirms this efficacy.


Asunto(s)
Antifibrinolíticos , Artritis , Artroplastia de Reemplazo de Rodilla , Hemofilia A , Ácido Tranexámico , Humanos , Ácido Tranexámico/uso terapéutico , Artroplastia de Reemplazo de Rodilla/efectos adversos , Artroplastia de Reemplazo de Rodilla/métodos , Estudios Retrospectivos , Hemofilia A/complicaciones , Hemofilia A/tratamiento farmacológico , Antifibrinolíticos/uso terapéutico , Pérdida de Sangre Quirúrgica/prevención & control , Hemorragia Posoperatoria/etiología , Inyecciones Intraarticulares , Inflamación/complicaciones , Biomarcadores , Dolor
10.
Angew Chem Int Ed Engl ; 63(24): e202405139, 2024 Jun 10.
Artículo en Inglés | MEDLINE | ID: mdl-38588277

RESUMEN

It remains challenging to comprehensively understand the packing models of conjugated polymers, in which side chains play extremely critical roles. The side chains are typically flexible and non-conductive and are widely used to improve the polymer solubility in organic solutions. Herein, a buffer chain model is proposed to describe link between conjugated backbone and side chains for understanding the relationship of crystallization competition of conductive conjugated backbones and non-conductive side chains. A longer buffer chain is beneficial for alleviating such crystallization competition and further promoting the spontaneous packing of conjugated backbones, resulting in enhanced charge transport properties. Our results provide a novel concept for designing conjugated polymers towards ordered organization and enhanced electronic properties and highlight the importance of balancing the competitive interactions between different parts of conjugated polymers.

11.
J Neurooncol ; 161(2): 415-423, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-36811765

RESUMEN

PURPOSE: Brain invasion in meningiomas is considered an indicator of more aggressive behavior and worse prognosis. But the precise definition and the prognostic role of brain invasion remains unsolved duo to lacking a standardized workflow of surgical sampling and the histopathological detection. Searching for molecular biomarker expression correlating with brain invasion, could contribute to establish a molecular pathological diagnosis without problems of subjective interobserver variation and deeply understand the mechanism of brain invasion and develop innovative therapeutic strategies. METHODS: We utilized liquid chromatography tandem mass spectrometry to quantify protein abundances between non-invasive meningiomas (n = 21) and brain-invasive meningiomas (n = 21) spanning World Health Organization grades I and III. After proteomic discrepancies were analyzed, the 14 most up-regulated or down-regulated proteins were recorded. Immunohistochemical staining for glial fibrillary acidic protein and most likely brain invasion-related proteins was performed in both groups. RESULTS: A total of 6498 unique proteins were identified in non-invasive and brain-invasive meningiomas. Canstatin expression in the non-invasive group was 2.1-fold that of the brain-invasive group. The immunohistochemical staining showed canstatin expressed in both groups, and the non-invasive group showed stronger staining for canstatin in the tumor mass (p = 0.0132) than the brain-invasive group, which showed moderate intensity. CONCLUSION: This study demonstrated the low expression of canstatin in meningiomas with brain invasion, a finding that provide a basis for understanding the mechanism of brain invasion of meningiomas and may contribute to establish molecular pathological diagnosis and identify novel therapeutic targets for personalized care.


Asunto(s)
Neoplasias Meníngeas , Meningioma , Humanos , Meningioma/patología , Colágeno Tipo IV/metabolismo , Inhibidores de la Angiogénesis , Cromatografía Liquida , Proteómica , Espectrometría de Masas en Tándem , Encéfalo/patología , Neoplasias Meníngeas/patología
12.
Sensors (Basel) ; 23(9)2023 May 06.
Artículo en Inglés | MEDLINE | ID: mdl-37177720

RESUMEN

The secondary-phase grating-based tomographic microscopy system, which is widely used in the biological and life sciences, can observe all the sample multilayer image information simultaneously because it has multifocal points. However, chromatic aberration exists in the grating diffraction, which seriously affects the observation of the image. To correct the chromatic aberration of the tomographic microscope system, this paper proposes a system that adopts blazed gratings and angle-variable reflectors as chromatic aberration correction devices according to the principle of dispersion compensation and Fourier phase-shift theory. A reflector-separated light dispersion-compensated 3D microscopy system is presented to achieve chromatic aberration correction while solving the problem of multilayer image overlap. The theoretical verification and optical design of the system were completed using ZEMAX software. The results show that the proposed system reduced the chromatic aberration of ordinary tomographic microscopy systems by more than 90%, retaining more wavelengths of light information. In addition, the system had a relatively wide range in the color difference compensation element installation position, reducing the difficulty of dispersion compensation element installation. Overall, the results indicate that the proposed system is effective in reducing chromatic aberration in grating diffraction.

13.
Sensors (Basel) ; 23(2)2023 Jan 12.
Artículo en Inglés | MEDLINE | ID: mdl-36679691

RESUMEN

To address the shortcomings in many traditional spectral feature extraction algorithms in practical application of low modeling accuracy and poor stability, this paper introduces the "Boruta algorithm-based local optimization process" based on the traditional simulated annealing algorithm and proposes the "two-step simulated annealing algorithm (TSSA)". This algorithm combines global optimization and local optimization. The Boruta algorithm ensures that the feature extraction results are all strongly correlated with the dependent variable, reducing data redundancy. The accuracy and stability of the algorithm model are significantly improved. The experimental results show that compared with the traditional feature extraction method, the accuracy indexes of the inversion model established by using the TSSA algorithm for feature extraction were significantly improved, with the determination coefficient R2 of 0.9654, the root mean square error (RMSE) of 3.6723 µg/L, and the mean absolute error (MAE) of 3.1461 µg/L.


Asunto(s)
Algoritmos
14.
J Minim Access Surg ; 2023 Sep 14.
Artículo en Inglés | MEDLINE | ID: mdl-37843162

RESUMEN

Introduction: In immunotherapy, antibodies are activated to block immune checkpoints, resist tumour immunosuppression, shrink tumours and prevent a recurrence. As the science behind tumour immunotherapy continuously develops and improves, neoadjuvant immunotherapy bears more prominent advantages: antigen exposure not only enhances the degree of tumour-specific T-cell response but also prolongs the duration of actions. In this study, we evaluated the efficacy and safety of McKeown minimally invasive oesophagectomy (McKeown MIO) following neoadjuvant immunotherapy combined with chemotherapy (NICT) in patients with locally advanced oesophageal cancer (OC). Patients and Methods: In this retrospective study, 94 patients underwent either NICT or neoadjuvant chemotherapy (NCT) followed by MIO at our institution from January 2020 to October 2022. We assessed the therapy-related adverse events and perioperative outcomes and compared them between the two groups. Results: After completing at least two cycles of neoadjuvant therapy, all patients underwent McKeown MIO with negative margins within 4-7 weeks. Demographic data of the two cohorts were similar. Regarding perioperative characteristics, the median intraoperative blood loss was 50 ml in the NICT group, lower than that of the NCT group (100 ml, P < 0.05). In addition, the NICT group had significantly more harvested lymph nodes than the NCT group (P < 0.05). No significant differences were found in post-operative complications. The rate of objective response rate in the NICT group was higher than that in the NCT group (88.3% vs. 58.8%). Regarding tumour regression, the number of patients with TRG Grades 1-3 in the NICT group was more than that in the NCT. Adverse events experienced by the two groups included anaemia and elevated transaminase. We found no difference in the adverse events between the two groups. Conclusions: This study showed the efficacy and feasibility of NICT followed by McKeown MIO in treating locally advanced OC.

15.
J Am Chem Soc ; 144(7): 3091-3098, 2022 Feb 23.
Artículo en Inglés | MEDLINE | ID: mdl-35138831

RESUMEN

BN-embedded polycyclic aromatic hydrocarbons (PAHs) with unique optoelectronic properties are underdeveloped relative to their carbonaceous counterparts due to the lack of suitable and facile synthetic methods. Moreover, the dearth of electron-deficient BN-embedded PAHs further hinders their application in organic electronics. Here we present the first facile synthesis of novel perylene diimide derivatives (B2N2-PDIs) featuring n-type B-N covalent bonds. The structures of these compounds are fully confirmed through the detailed characterizations with NMR, MS, and X-ray crystallography. Further investigation shows that the introduction of BN units significantly modifies the photophysical and electronic properties of these B2N2-PDIs and is further understood with the aid of theoretical calculations. Compared with the parent perylene diimides (PDIs), B2N2-PDIs exhibit deeper highest occupied molecular orbital energy levels, new absorption peaks in the high-energy region, hypsochromic shift of absorption and emission maxima, and decrement of photoluminescent quantum yields. Single-crystal field-effect transistors based on B2N2-PDIs showcase an electron mobility up to 0.35 cm2 V-1 s-1, demonstrating their potential application in optoelectronic materials.

16.
Acc Chem Res ; 54(13): 2871-2883, 2021 Jul 06.
Artículo en Inglés | MEDLINE | ID: mdl-34152131

RESUMEN

ConspectusMolecular doping is one of the most central propositions in the field of organic electronics. Unlike classical inorganic semiconductors doped by atomic substitution, organic conjugated materials react with molecular dopants, and then intermolecular charge transfer is involved within. Therefore, the complex noncovalent interactions between two components often cause the molecular dopant to destroy the orderly stacking of the host organic materials and reduce the original properties of the material, such as carrier mobility, which here we call the "doping dilemma." Recently, many studies focus on improving p-doping efficiency and electrical conductivity of doped conjugated polymers; however, the development of n-type molecular doping currently lags far behind that of its p-counterpart. It is well-known that both efficient p- and n-type molecular doping are indispensable in various organic electronic devices, including light-emitting diodes, photovoltaics, field-effect transistors, and thermoelectrics. It is thus an urgent requirement to achieve efficient n-doping in conjugated polymers.In this Account, we give a brief overview of our efforts to improve the n-doping efficiency in conjugated polymers with several strategies from the aspects of the polymer/dopant molecular design and the exploration of the n-type molecular doping mechanism and charge transport mechanism in n-doped organic materials. For the conjugated polymer engineering, we first demonstrate that increasing the electron affinity of the host polymer through halogen substitution can boost the n-doping efficiency. Still, the rigid coplanar backbones of conjugated polymers play a crucial role in the polaron delocalization and final electrical performance. In addition, we emphasize the importance of morphology control in the doped polymers to address the "doping dilemma." For n-dopants designing, we summarize some basic guidelines from molecular sizes and shapes, the interaction between dopants (or dopant cations) and polymers, and the effects of dopants on morphology to design high-efficacy n-type molecular dopants. We propose that the polymers and the dopants need to be treated as a whole system; while enhancing the ionization efficiency, more attention should be paid to the carrierization (free-carrier generation) efficiency of these binary systems. In the end, we adopt the n-type polymer thermoelectric material as an example to discuss the grand challenges encountered in practical applications of n-doped conjugated polymers. The air stability and micrometer-thick thermo-leg processing of n-doped polymers are highlighted for thermoelectric applications. It is our hope that this Account showcases a blueprint for rational approaches and a deep understanding toward the design and development of efficient n-doping in conjugated polymers, bringing n-doped organic materials into the next era.

17.
Macromol Rapid Commun ; 43(16): e2200069, 2022 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-35362637

RESUMEN

Molecular ordering of conjugated polymers both in solution-state aggregates and in solid-state microstructures is a determining factor of the charge transport properties in optoelectronic devices. However, the effect of backbone conformation in conjugated polymers on assembly structures is still unclear. Herein, to understand such backbone conformation effect, three novel chlorinated benzodifurandionge-based oligo(p-phenylene vinylene) (BDOPV) polymers are systematically developed. These BDOPV-based polymers exhibit significantly twisted backbone conformation (near 90° interunit torsion angle) between conjugated units, which can prevent polymer chains from forming ordered assembly structures by increasing conformational energy penalty in closely packed chains. A higher rotational barrier of the torsion angle would further prevent polymer chains from assembling, finally resulting in nonaggregated chains in solution and highly disordered solid-state packing structures. This work will deepen the understanding of the relationship between polymer backbone conformation and assembly structures, contributing to the exploration of the structure-property relationship of polymers.


Asunto(s)
Polímeros , Conformación Molecular , Polímeros/química
18.
BMC Musculoskelet Disord ; 23(1): 587, 2022 Jun 17.
Artículo en Inglés | MEDLINE | ID: mdl-35715793

RESUMEN

BACKGROUND: Total knee arthroplasty is the leading way to treat hemophilia arthritis. At present, there is a lack of research on the influencing factors of blood loss in total knee arthroplasty for hemophilia arthritis. This study comprehensively explores the definite factors affecting the hidden blood loss in total knee arthroplasty for hemophilia patients. MATERIALS AND METHODS: Ninety-two hemophilia A patients who underwent total knee arthroplasty in our center were included. Demographics, laboratory data, surgical data, and complications were collected. The Gross equation and Sehat equation were used to calculate the estimated value of hidden blood loss. Multivariate linear regression analysis was used to determine the influencing factors of hidden blood loss. RESULT: The hidden blood loss of hemophilia A patients undergoing total knee arthroplasty was 1069.51 ± 341.99 mL, and the age was positively correlated with the hidden blood loss (P < 0.001), while tranexamic acid, FVIII prophylaxis, and incremental invivo recovery were negatively correlated with the hidden blood loss (P < 0.001, P = 0.008, P = 0.017). CONCLUSION: Elderly patients have a greater risk of blood loss, and additional preventive measures can be appropriately added. Intraoperative intra-articular injection of tranexamic acid is recommended to reduce hidden blood loss, FVIII prophylaxis is recommended for every patient. We recommend that all HA patients measure the incremental invivo recovery and develop a personalized infusion regimen of coagulation factor.


Asunto(s)
Antifibrinolíticos , Artritis , Artroplastia de Reemplazo de Rodilla , Hemofilia A , Ácido Tranexámico , Anciano , Antifibrinolíticos/efectos adversos , Artritis/etiología , Artritis/cirugía , Artroplastia de Reemplazo de Rodilla/efectos adversos , Pérdida de Sangre Quirúrgica/prevención & control , Transfusión Sanguínea , Hemofilia A/complicaciones , Hemofilia A/tratamiento farmacológico , Humanos , Hemorragia Posoperatoria/prevención & control , Ácido Tranexámico/uso terapéutico
19.
Sensors (Basel) ; 22(3)2022 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-35161858

RESUMEN

A tomographic microscopy system can achieve instantaneous three-dimensional imaging, and this type of microscopy system has been widely used in the study of biological samples; however, existing chromatographic microscopes based on off-axis Fresnel zone plates have degraded image quality due to geometric aberrations such as spherical aberration, coma aberration, and image scattering. This issue hinders the further development of chromatographic microscopy systems. In this paper, we propose a method for the design of an off-axis Fresnel zone plate with the elimination of aberrations based on double exposure point holographic surface interference. The aberration coefficient model of the optical path function was used to solve the optimal recording parameters, and the principle of the aberration elimination tomography microscopic optical path was verified. The simulation and experimental verification were carried out utilizing a Seidel coefficient, average gradient, and signal-to-noise ratio. First, the aberration coefficient model of the optical path function was used to solve the optimal recording parameters. Then, the laminar mi-coroscopy optical system was constructed for the verification of the principle. Finally, the simulation calculation results and the experimental results were verified by comparing the Seidel coefficient, average gradient, and signal-to-noise ratio of the microscopic optical system before and after the aberration elimination. The results show that for the diffractive light at the orders 0 and ±1, the spherical aberration W040 decreases by 62-70%, the coma aberration W131 decreases by 96-98%, the image dispersion W222 decreases by 71-82%, and the field curvature W220 decreases by 96-96%, the average gradient increases by 2.8%, and the signal-to-noise ratio increases by 18%.


Asunto(s)
Holografía , Simulación por Computador , Microscopía , Relación Señal-Ruido , Tomografía Computarizada por Rayos X
20.
Angew Chem Int Ed Engl ; 61(14): e202200221, 2022 Mar 28.
Artículo en Inglés | MEDLINE | ID: mdl-35107203

RESUMEN

Strong interchain interactions of conjugated polymers usually result in poor miscibility with molecular dopants, limiting the doping efficiency because of uncontrolled phase separation. We have developed a strategy to achieve efficient charge-transport and high doping miscibility in n-doped conjugated polymers. We solve the miscibility issue through disorder side-chains containing dopants better. Systemic structural characterization reveals a farther side-chain branching point will lead to higher disorders, which provides appropriate sites to accommodate extrinsic molecular dopants without harming original chain packings and charge-transport channels. Therefore, better sustainability of solid-state microstructure is obtained, yielding a stable conductivity even when overloading massive dopants. This work highlights the importance of realizing high host-dopant miscibility in molecular doping of conjugated polymers.

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