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1.
Chempluschem ; : e202400286, 2024 Jun 10.
Artículo en Inglés | MEDLINE | ID: mdl-38858773

RESUMEN

n-Type organic conductive molecules play a significant role in organic electronics. Self-doping can increase the carrier concentration within the materials to improve the conductivity without the need for additional intentional dopants. This review focuses on the various strategies employed in the synthesis of self-doped n-type molecules, and provides an overview of the doping mechanisms. By elucidating these mechanisms, the review aims to establish the relationship between molecular structure and electronic properties. Furthermore, the review outlines the current applications of self-doped n-type molecules in the field of organic electronics, highlighting their performance and potential in various devices. It also offers insights into the future development of self-doped materials.

2.
Angew Chem Int Ed Engl ; 63(25): e202402375, 2024 Jun 17.
Artículo en Inglés | MEDLINE | ID: mdl-38619528

RESUMEN

Open-shell conjugated polymers with a high intrinsic conductivity and high-spin ground state hold considerable promise for applications in organic electronics and spintronics. Herein, two novel acceptor-acceptor (A-A) conjugated polymers based on a highly electron-deficient quinoidal benzodifurandione unit have been developed, namely DPP-BFDO-Th and DPP-BFDO. The incorporation of the quinoidal moiety into the polymers backbones enables deeply aligned lower-lying lowest unoccupied molecular orbital (LUMO) levels of below -4.0 eV. Notably, DPP-BFDO exhibits an exceptionally low LUMO (-4.63 eV) and a high-spin ground state characterized by strong diradical characters. Moreover, a self-doping through intermolecular charge-transfer is observed for DPP-BFDO, as evidenced by X-ray photoelectron spectroscopy (XPS) studies. The high carrier concentration in combination with a planar and linear conjugated backbone yields a remarkable electrical conductivity (σ) of 1.04 S cm-1 in the "undoped" native form, ranking among the highest values reported for n-type radical-based conjugated polymers. When employed as an n-type thermoelectric material, DPP-BFDO achieves a power factor of 12.59 µW m-1 K-2. Furthermore, upon n-doping, the σ could be improved to 65.68 S cm-1. This study underscores the great potential of electron-deficient quinoidal units in constructing dopant-free n-type conductive polymers with a high-spin ground state and exceptional intrinsic conductivity.

3.
Angew Chem Int Ed Engl ; 63(20): e202402642, 2024 May 13.
Artículo en Inglés | MEDLINE | ID: mdl-38453641

RESUMEN

Conjugated polymers (CPs) with low crystallinity are promising candidates for application in organic thermoelectrics (OTEs), particularly in flexible devices, because the disordered structures of these CPs can effectively accommodate dopants and ensure robust resistance to bending. However, n-doped CPs usually exhibit poor thermoelectric performance, which hinders the development of high-performance thermoelectric generators. Herein, we report an n-type CP (ThDPP-CNBTz) comprising two acceptor units: a thiophene-flanked diketopyrrolopyrrole and a cyano-functionalized benzothiadiazole. ThDPP-CNBTz shows a low LUMO energy level of below -4.20 eV and features low crystallinity, enabling high doping efficiency. Moreover, the dual-acceptor design enhances polaron delocalization, resulting in good thermoelectric performance. After n-doping, ThDPP-CNBTz exhibits an average electrical conductivity (σ) of 50.6 S cm-1 and a maximum power factor (PF) of 126.8 µW m-1 K-2, which is among the highest values reported for solution-processed n-type CPs to date. Additionally, a solution-processed flexible OTE device based on doped ThDPP-CNBTz exhibits a maximum PF of 70 µW m-1 K-2; the flexible device also shows remarkable resistance to bending strain, with only a marginal change in σ after 600 bending cycles. The findings presented in this work will advance the development of n-type CPs for OTE devices, and flexible devices in particular.

4.
Heliyon ; 10(4): e26326, 2024 Feb 29.
Artículo en Inglés | MEDLINE | ID: mdl-38404868

RESUMEN

Dyslipidemia often accompanies type 2 diabetes mellitus (T2DM). Elevated blood glucose in patients commonly leads to high levels of lipids. Lipid molecules can play a crucial role in early detection, treatment, and prognosis of T2DM with dyslipidemia. Previous lipid studies on T2DM mainly focused on Western diabetic populations with elevated blood glucose. In this research, we investigate both high blood sugar and high lipid levels to better understand changes in plasma lipid metabolism in newly diagnosed Chinese T2DM patients with dyslipidemia (NDDD). We used a plasma lipid analysis method based on ultra-high performance liquid chromatography coupled with mass spectrometry technology (UHPLC-MS) and statistical analysis to characterize lipid profiles and identify potential biomarkers in NDDD patients compared to healthy control (HC) subjects. Additionally, we examined the differences in lipid profiles between hyperlipidemia (HL) patients and HC subjects. We found significant changes in 15 and 23 lipid molecules, including lysophosphatidylcholine (LysoPC), phosphatidylcholine (PC), phosphatidylethanolamine (PE), sphingomyelin (SM), and ceramide (Cer), in the NDDD and HL groups compared to the HC group. These altered lipid molecules are associated with five metabolic pathways, with sphingolipid metabolism and glycerophospholipid metabolism being the most relevant to glucose and lipid metabolism changes. These lipid biomarkers are strongly correlated with traditional markers of glucose and lipid metabolism. Notably, Cer(d18:1/24:0), SM(d18:1/24:0), SM(d18:1/16:1), SM(d18:1/24:1), and SM(d18:2/24:1) were identified as essential potential biomarkers closely linked to clinical parameters through synthetic analysis of receiver operating characteristic curves, random forest analysis, and Pearson matrix correlation. These lipid biomarkers can enhance the risk prediction for the development of T2DM in individuals with dyslipidemia but no clinical signs of high blood sugar. Furthermore, they offer insights into the pathological mechanisms of T2DM with dyslipidemia.

5.
Macromol Rapid Commun ; 45(1): e2300245, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37278130

RESUMEN

A series of thienoisoindigo (TIG)-based conjugated polymers (CPs) with high molecular weights are synthesized by direct arylation polycondensation (DArP) by using TIG derivatives as CBr monomer and multi-halogenated thiophene derivatives, i.e., (E)-1,2-bis(3,4-difluorothien-2-yl)ethene (4FTVT), (E)-1,2-bis(3,4-dichlorothien-2-yl)ethene (4ClTVT), 3,3',4,4'-tetrafluoro-2,2'-bithiophene (4FBT), and 3,3',4,4'-tetrachloro-2,2'-bithiophene (4ClBT), as CH monomers. Density functional theory (DFT) calculations reveal the high selectivity between α-CH bonds in 4FTVT, 4ClTVT, 4FBT, and 4ClBT and ß-CH bonds in TIG CBr monomer. All four resulting CPs exhibit low optical bandgaps of ca. 1.20 eV and ambipolar transport characteristics with both electron and hole mobility above 0.1 cm2  V-1  s-1 as elaborated with organic thin-film transistors (OTFTs). The polymer TIG-4FTVT delivers the best device performance. With this polymer, n-channel OTFTs with electron mobility up to 1.67 cm2  V-1  s-1 and p-channel OTFTs with hole mobility up to 0.62 cm2  V-1  s-1 are fabricated by modifying source/drain electrodes with polyethylenimine ethoxylated (PEIE) and MoO3 , respectively, to selectively inject electrons and holes.


Asunto(s)
Etilenos , Polímeros , Polímeros/química , Tiofenos/química , Electrones
6.
Light Sci Appl ; 12(1): 264, 2023 Nov 07.
Artículo en Inglés | MEDLINE | ID: mdl-37932276

RESUMEN

The neuromorphic vision sensor (NeuVS), which is based on organic field-effect transistors (OFETs), uses polar functional groups (PFGs) in polymer dielectrics as interfacial units to control charge carriers. However, the mechanism of modulating charge transport on basis of PFGs in devices is unclear. Here, the carboxyl group is introduced into polymer dielectrics in this study, and it can induce the charge transfer process at the semiconductor/dielectric interfaces for effective carrier transport, giving rise to the best device mobility up to 20 cm2 V-1 s-1 at a low operating voltage of -1 V. Furthermore, the polarity modulation effect could further increase the optical figures of merit in NeuVS devices by at least an order of magnitude more than the devices using carboxyl group-free polymer dielectrics. Additionally, devices containing carboxyl groups improved image sensing for light information decoding with 52 grayscale signals and memory capabilities at an incredibly low power consumption of 1.25 fJ/spike. Our findings provide insight into the production of high-performance polymer dielectrics for NeuVS devices.

7.
Macromol Rapid Commun ; 44(23): e2300393, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37640284

RESUMEN

3,4-Difluorothiophene-substituted aryls, i.e., 1,4-bis(3,4-difluorothiophen-2-yl)-benzene (Ph-2FTh), 1,4-bis(3,4-difluorothiophen-2-yl)-2,5-difluorobenzene (2FPh-2FTh), and 4,7-bis(3,4-difluorothiophen-2-yl)-2,1,3-benzothiadiazole (BTz-2FTh), are synthesized as C─H monomers for the synthesis of conjugated polymers (CPs) via direct arylation polycondensation (DArP) with diketopyrrolopyrrole (DPP) and isoindigo (IID) derivatives as C─Br monomers. The Gibbs free energies of activation for direct arylation (ΔG298 K , kcal mol-1 ) for α─C─H bonds of thiophene moieties as calculated by density functional theory (DFT) are 14.3, 16.5, and 16.4 kcal mol-1 for Ph-2FTh, 2FPh-2FTh and BTz-2FTh, respectively, meaning that inserting an electron-deficient unit in 3,3',4,4'-tetrafluoro-2,2'-bithiophene (4FBT, ΔG298K : 14.6 kcal mol-1 ) may cause a reactivity decrease of the C─H monomers. Photophysical and semiconducting properties of the resulting six CPs (i.e., DPP-Ph, DPP-2FPh, DPP-BTz, 2FIID-Ph, 2FIID-2FPh, and 2FIID-BTz) are characterized in detail. DPP-based CPs show ambipolar transport properties while IID-based ones exhibited n-type behavior owing to the deeper frontier molecular orbital energy levels of IID-based CPs. With source/drain electrodes modified with polyethylenimine ethoxylated, n-channel organic thin-film transistors with maximum electron mobility of 0.40, 0.54, 0.29, 0.05, 0.16, and 0.01 cm2 V-1 s-1 for DPP-Ph, DPP-2FPh, DPP-BTz, 2FIID-Ph, 2FIID-2FPh, and 2FIID-BTz, respectively, are fabricated. DPP-2FPh exhibits the best device performance due to the good film morphology and the highest intermolecular packing order.


Asunto(s)
Polímeros , Pirroles , Embarazo , Humanos , Femenino , Polímeros/química , Pirroles/química , Cetonas , Tiofenos/química
8.
FEMS Microbiol Lett ; 3702023 01 17.
Artículo en Inglés | MEDLINE | ID: mdl-37451707

RESUMEN

Pseudomonas aeruginosa is a common bacteria that may cause a wide range of severe illnesses in humans. One of the nonantibiotic therapies, antivirulence factor therapy, has attracted ongoing interest. Screening for and investigating bacterial virulence factor inhibitors is critical for the development of antivirulence factor treatments. Pyocyanin is P. aeruginosa's distinctive pigment, and it plays a key role in infection. The impact of low concentration ethanol on pyocyanin production was investigated in this research. Pyocyanin production was found both subjectively and quantitatively. The effects of ethanol on the expression of pyocyanin production genes were studied using qRT-PCR and western blotting. The findings demonstrated that low concentrations of ethanol (as little as 0.1%) greatly suppressed pyocyanin production without affecting P. aeruginosa growth. The degree of inhibition increased as the ethanol contentration rose. Ethanol inhibits the expression of genes involved in pyocyanin production. This inhibitory impact was mostly seen at the protein level. Further research revealed that ethanol increased the expression of the post-transcriptional regulator RsmA, which inhibits pyocyanin production. Given the favorable relationship between pyocyanin production and antibiotic resistance, the impact of low concentration ethanol on various antibiotics was investigated. Ethanol lowered antibiotic resistance in P. aeruginosa, presumably by inhibiting pyocyanin.


Asunto(s)
Pseudomonas aeruginosa , Piocianina , Humanos , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo , Factores de Virulencia/metabolismo , Antibacterianos/farmacología , Antibacterianos/metabolismo , Farmacorresistencia Microbiana , Percepción de Quorum
9.
Angew Chem Int Ed Engl ; 62(35): e202307856, 2023 Aug 28.
Artículo en Inglés | MEDLINE | ID: mdl-37402633

RESUMEN

Air stable n-type conductive molecules with high electrical conductivities and excellent device performance have important applications in organic electronics, but their synthesis remains challenging. Herein, we report three self-doped n-type conductive molecules, designated QnNs, with a closed-shell quinoidal backbone and alkyl amino chains of different lengths. The QnNs are self-doped by intermolecular electron transfer from the amino groups to the quinoidal backbone. This process is ascertained unambiguously by experiments and theoretical calculations. The use of a quinoidal structure effectively improves the self-doping level, and thus increases the electrical conductivity of self-doped n-type conductive molecules achieved by a closed-shell structure from<10-4  S cm-1 to>0.03 S cm-1 . Furthermore, the closed-shell quinoidal structure results in good air stability of the QnNs, with half-lives>73 days; and Q4N shows an electrical conductivity of 0.019 S cm-1 even after exposure to air for 120 days. When applying Q6N as the cathode interlayer in organic solar cells (OSCs), an outstanding power conversion efficiency of up to 18.2 % was obtained, which represents one the best results in binary OSCs.

10.
Org Lett ; 25(15): 2565-2570, 2023 Apr 21.
Artículo en Inglés | MEDLINE | ID: mdl-37043302

RESUMEN

A convergent (outside-to-center) route was adopted to synthesize the precursors of quinoidal compounds in high yields of 85-93%. With subsequent rearrangement/dehydroxylation and oxidation, a series of thiophene-based quinoids with indandione or oxindole terminal groups were successfully synthesized. This strategy shows good compatibility with versatile central and terminal units, leading to quinoidal compounds with tunable properties.

11.
Nat Commun ; 14(1): 2281, 2023 Apr 21.
Artículo en Inglés | MEDLINE | ID: mdl-37085540

RESUMEN

Sensing and recognizing invisible ultraviolet (UV) light is vital for exploiting advanced artificial visual perception system. However, due to the uncertainty of the natural environment, the UV signal is very hard to be detected and perceived. Here, inspired by the tetrachromatic visual system, we report a controllable UV-ultrasensitive neuromorphic vision sensor (NeuVS) that uses organic phototransistors (OPTs) as the working unit to integrate sensing, memory and processing functions. Benefiting from asymmetric molecular structure and unique UV absorption of the active layer, the as fabricated UV-ultrasensitive NeuVS can detect 370 nm UV-light with the illumination intensity as low as 31 nW cm-2, exhibiting one of the best optical figures of merit in UV-sensitive neuromorphic vision sensors. Furthermore, the NeuVS array exbibits good image sensing and memorization capability due to its ultrasensitive optical detection and large density of charge trapping states. In addition, the wavelength-selective response and multi-level optical memory properties are utilized to construct an artificial neural network for extract and identify the invisible UV information. The NeuVS array can perform static and dynamic image recognition from the original color image by filtering red, green and blue noise, and significantly improve the recognition accuracy from 46 to 90%.

12.
Angew Chem Int Ed Engl ; 62(20): e202219262, 2023 May 08.
Artículo en Inglés | MEDLINE | ID: mdl-36917081

RESUMEN

n-Type conjugated polymers (CPs) are crucial in the applications of organic electronics. Direct coupling of electron-deficient C-H monomer via selective C-H activation, namely C-H/C-H oxidative direct arylation polycondensation (Oxi-DArP), is an ideal approach toward such CPs. Herein, Oxi-DArP is firstly adopted to synthesize a high-performance n-type CP using a newly developed monomer, i.e., 3,6-di(thiazol-5-yl)-diketopyrrolopyrrole (Tz-5-DPP). Tz-5-DPP based homopolymer PTz-5-DPP with a molecular weight of 22 kDa has been synthesized via Oxi-DArP. After n-doping, PTz-5-DPP films exhibited electric conductivity values up to 8 S cm-1 and power factors (PFs) up to 106 µW m-1 K-2 . Notably, this PF value is the highest for n-type polymer thermoelectric materials to date. The Oxi-DArP synthesis and the excellent n-type performance of the polymer make this work an important step toward the straightforward and sustainable preparation of high-performance n-type polymer semiconductors.

13.
Microorganisms ; 11(2)2023 Feb 06.
Artículo en Inglés | MEDLINE | ID: mdl-36838372

RESUMEN

Waste oil pollution and the treatment of oily waste present a challenge, and the exploitation of microbial resources is a safe and efficient method to resolve these problems. Lipase-producing microorganisms can directly degrade waste oil and promote the degradation of oily waste and, therefore, have very significant research and application value. The isolation of efficient oil-degrading strains is of great practical significance in research into microbial remediation in oil-contaminated environments and for the enrichment of the microbial lipase resource library. In this study, Acinetobacter junii WCO-9, an efficient oil-degrading bacterium, was isolated from an oil-contaminated soil using olive oil as the sole carbon source, and its enzyme activity of ρ-nitrophenyl decanoate (ρ-NPD) decomposition was 3000 U/L. The WCO-9 strain could degrade a variety of edible oils, and its degradation capability was significantly better than that of the control strain, A junii ATCC 17908. Comparative pan-genome and lipid degradation pathway analyses indicated that A. junii isolated from the same environment shared a similar set of core genes and that the species accumulated more specific genes that facilitated resistance to environmental stresses under different environmental conditions. WCO-9 has accumulated a complete set of oil metabolism genes under a long-term oil-contamination environment, and the compact arrangement of abundant lipase and lipase chaperones has further strengthened the ability of the strain to survive in such environments. This is the main reason why WCO-9 is able to degrade oil significantly more effectively than ATCC 17908. In addition, WCO-9 possesses a specific lipase that is not found in homologous strains. In summary, A. junii WCO-9, with a complete triglyceride degradation pathway and the specific lipase gene, has great potential in environmental remediation and lipase for industry.

14.
Emerg Microbes Infect ; 12(1): 2148564, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-36377487

RESUMEN

BACKGROUND: Posterior oropharyngeal saliva (POS) is increasingly recognized as an alternative specimen for detecting respiratory pathogens. The accuracy of Xpert® MTB/RIF Ultra (X-Ultra), when performed on POS obtained from patients with paucibacillary pulmonary tuberculosis (TB) is unclear. METHODS: We consecutively recruited adults with symptoms suggestive of pulmonary TB who were negative by both smear microscopy and Xpert MTB/RIF (X-Classic). Each participant was required to provide one bronchoalveolar lavage fluid (BALF) and one POS specimen, respectively. Diagnostic performances of X-Ultra and X-Classic on POS were compared against clinical and mycobacterial reference standards. FINDINGS: 686 participants meeting inclusion criteria were consecutively enrolled into the study. The overall diagnostic sensitivities of X-Ultra and X-Classic on POS samples were 78.9% [95% confidence interval (CI): 72.8-83.8] and 56.4% (95% CI: 49.7-62.9), respectively; the specificities were 96.6% (95% CI: 94.3-98.1) for X-Ultra and 97.6 (95CI: 95.5-98.8) for X-Classic in POS specimens. Notably, the sensitivity of X-Ultra on POS was as sensitive as X-Classic on BALF against microbiological reference standard (78.9% VS 73.1%). Against clinical diagnosis as a reference standard, the sensitivities of X-Ultra and X-Classic on POS were 55.9% (95% CI: 50.5-61.2; 193/345) and 40.0% (95% CI: 34.8-45.4; 138/345), respectively. The risk of negative results with POS was dramatically increased with decreasing bacterial loads. CONCLUSIONS: The testing of POS using X-Ultra shows promise as a tool to identify patients with paucibacillary TB. Considering that bronchoscopy is a semi-invasive procedure, POS testing ahead of bronchoscopy, may decrease the need for bronchoscopic procedures, and the cost of care.


Asunto(s)
Antibióticos Antituberculosos , Mycobacterium tuberculosis , Tuberculosis Pulmonar , Adulto , Humanos , Antibióticos Antituberculosos/uso terapéutico , Mycobacterium tuberculosis/genética , Rifampin , Estudios Prospectivos , Sensibilidad y Especificidad , Tuberculosis Pulmonar/diagnóstico , Tuberculosis Pulmonar/microbiología
15.
Chemistry ; 29(12): e202203336, 2023 Feb 24.
Artículo en Inglés | MEDLINE | ID: mdl-36456528

RESUMEN

Quinoidal compounds have great potential utility as high-performance organic semiconducting materials because of their rigid planar structures and extended π-conjugation. However, the existence of E and Z isomers adversely affects the charge-transport properties of quinoidal compounds. In this study, three isomerically pure oxindole-terminated quinoids were developed by introducing chlorine atoms in the quinoidal core. The synthesized quinoids were confirmed to have a Z,Z configuration by means of 1 H NMR spectroscopy, density functional theory calculations, and single-crystal X-ray analysis. Importantly, the strategy of chlorination allowed to maintain low-lying frontier molecular orbital energy levels and ensure favorable intermolecular packing. Consequently, all three quinoidal compounds showed n-type transport characteristics in organic thin-film transistors, with electron mobilities up to 0.35 cm2 V-1 s-1 , which is the highest value reported to date for oxindole-terminated quinoids. Our study can provide new guidelines for the design of isomerically pure quinoids with high electron mobilities.

16.
Emerg Microbes Infect ; 12(1): 2151382, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-36416478

RESUMEN

Early and accurate diagnosis of tuberculosis (TB) is necessary to initiate proper therapy for the benefit of the patients and to prevent disease transmission in the community. In this study, we developed the InnowaveDX MTB/RIF (InnowaveDX) to detect Mycobacterium tuberculosis (MTB) and rifampicin resistance simultaneously. A prospective multicentre study was conducted to evaluate the diagnostic performance of InnowaveDX for the detection MTB in sputum samples as compared with Xpert and culture. The calculated limit of detection (LOD) for InnowaveDX was 9.6 CFU/ml for TB detection and 374.9 CFU/ml for RIF susceptibility. None of the other bacteria tested produced signals that fulfilled the positive TB criteria, demonstrating a species-specificity of InnowaveDX. Then 951 individuals were enrolled at 7 hospitals, of which 607 were definite TB cases with positive culture and/or Xpert results, including 354 smear-positive and 253 smear-negative cases. InnowaveDX sensitivity was 92.7% versus bacteriologically TB standard. Further follow-up revealed that 61 (91.0%) out of 67 false-positive patients with no bacteriological evidence met the criteria of clinically diagnosed TB. Among 125 RIF-resistant TB patients diagnosed by Xpert, 108 cases were correctly identified by InnowaveDX, yielding a sensitivity of 86.4%. Additionally, the proportion of very low bacterial load in the discordant susceptibility group was significantly higher than in the concordant susceptibility group (P = 0.029). To conclude, we have developed a novel molecular diagnostic with promising detection capabilities of TB and RIF susceptibility. In addition, the discordant RIF susceptibility results between InnowaveDX and Xpert are more frequently observed in samples with very low bacterial load.


Asunto(s)
Antibióticos Antituberculosos , Mycobacterium tuberculosis , Tuberculosis Resistente a Múltiples Medicamentos , Tuberculosis Pulmonar , Tuberculosis , Humanos , Rifampin/farmacología , Mycobacterium tuberculosis/genética , Antibióticos Antituberculosos/farmacología , Antibióticos Antituberculosos/uso terapéutico , Tuberculosis Pulmonar/diagnóstico , Estudios Prospectivos , Farmacorresistencia Bacteriana , Sensibilidad y Especificidad , Tuberculosis/diagnóstico , Tuberculosis/tratamiento farmacológico , Tuberculosis Resistente a Múltiples Medicamentos/microbiología
17.
Adv Mater ; 35(3): e2207884, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-36333886

RESUMEN

The stretchability and stretch-induced structural evolution of organic solar cells (OSCs) are pivotal for their collapsible, portable, and wearable applications, and they are mainly affected by the complex morphology of active layers. Herein, a highly ductile conjugated polymer P(NDI2OD-T2) is incorporated into the active layers of high-efficiency OSCs based on nonfullerene small molecule acceptors to simultaneously investigate the morphological, mechanical, and photovoltaic properties and structural evolution under stretching of ternary blend films with various acceptor contents. The structural robustness of the blend films is indicated by their stretch-induced structural evolution, which is monitored in real-time by a combination of in situ wide/small angle X-ray scattering. It is found that adding the soft P(NDI2OD-T2) can enhance the stretchability and structural robustness of ternary blend films by more entangled chains and tie chains to dissipate strain. Furthermore, the stretchability of the ternary blends can be superbly predicted by a 3D equivalent box model. This work provides instructive insight and guidance for designing stretchable electronics and predicting the stretchability of multicomponent blends.

18.
J Clin Med ; 11(16)2022 Aug 11.
Artículo en Inglés | MEDLINE | ID: mdl-36012934

RESUMEN

Mycobacterial culture remains the gold standard for the diagnosis of active tuberculosis. However, an appropriate digestion and decontamination method is essential for the effective recovery of tubercle bacilli in culture. The study was designed to compare the efficacy of sputum treated with power ultrasound (PU) and routine NALC-NaOH methods for mycobacterial culture from clinically suspected cases of pulmonary tuberculosis. To evaluate the PU and routine NALC-NaOH methods, sputum specimens (n = 597) were studied (culturing on MGIT 960), and the performances were compared. Of the 597 samples, 89 (14.91%) sputum samples treated with the NaOH-NALC method were mycobacterial culture positive, including Mycobacterium tuberculosis (M.TB; n = 77, 12.90%) and nontuberculous mycobacteria (NTM; n = 12, 2.01%). One hundred and ten (18.43%) sputum samples treated with the PU method were culture positive, including M.TB (n = 87, 14.57%) and NTM (n = 23, 3.85%). The PU method detected 10 additional cases of M.TB and 11 additional cases of NTM when compared to the NALC-NaOH method. Statistical analysis showed that a significant difference was found in the culture-positive ratio of M.TB and NTM between the two method groups (p < 0.05). Compared with that of the NALC-NaOH method (8.04%), sputum treated with PU method (4.86%) had a significantly lower contamination rate (p < 0.05). In conclusion, our data indicate that, compared with the NALC-NaOH method, the PU method is a rapid and effective approach for mycobacterial culture when detecting active TB. However, its accurate mechanism has not been well addressed, and further investigation is still required.

19.
Microbiol Spectr ; 10(4): e0094922, 2022 08 31.
Artículo en Inglés | MEDLINE | ID: mdl-35876568

RESUMEN

Due to the probability of decreased specificity, the practical value of performing the Xpert MTB/RIF Ultra (Xpert Ultra) assay over the Xpert assay for diagnosing pulmonary tuberculosis (TB) and rifampicin (RIF) resistance in a high TB burden setting was evaluated. Participants were recruited consecutively in three tertiary hospitals in China and allocated to the TB case detection and/or rifampicin (RIF) resistance detection group. Each sputum specimen was subjected to smear, MGIT960 liquid culture, and Xpert, and Xpert Ultra assay in parallel. Drug susceptibility testing was conducted for all recovered isolates in the RIF resistance detection group. In total, 1,079 patients were recruited to the case detection group and 450 to the RIF resistance detection group. Xpert Ultra had higher sensitivity than Xpert (92.26%, 322/349 versus 89.40%, 312/349; P = 0.006), whereas the most prominent increase was identified in the smear-negative patients (83.70% versus 78.52%; P = 0.039). The specificity of Xpert Ultra was slightly lower than that of Xpert (96.30%, 495/514 versus 98.25%, 505/514; P = 0.055). Reclassifying trace results as negative resulted in a 4.01% loss of sensitivity (from 92.26% to 88.25%) accompanied by a 1.37% gain in specificity (from 96.30% to 97.67%). Both the sensitivity (97.64% versus 99.21%, P = 0.313) and specificity (96.90% versus 97.21%, P = 0.816) of Xpert Ultra and Xpert for detection RIF resistance were comparable. In conclusion, Xpert Ultra could improve the diagnosis of smear-negative pulmonary TB in contrast to the Xpert assay. A high percentage of TB history did not significantly decrease the specificity of the test, which supports the potential role of Xpert Ultra as an initial diagnostic tool for TB. IMPORTANCE Xpert Ultra is more sensitive than Xpert, especially in smear-negative TB. A high percentage of TB history in the non-TB population did not significantly affect the reliability of the assay, which supports the potential role of Xpert Ultra as an initial diagnostic tool for TB.


Asunto(s)
Antibióticos Antituberculosos , Mycobacterium tuberculosis , Tuberculosis Pulmonar , Tuberculosis , Antibióticos Antituberculosos/farmacología , Antibióticos Antituberculosos/uso terapéutico , Farmacorresistencia Bacteriana , Humanos , Pruebas de Sensibilidad Microbiana , Mycobacterium tuberculosis/genética , Estudios Prospectivos , Reproducibilidad de los Resultados , Rifampin/farmacología , Sensibilidad y Especificidad , Tuberculosis/tratamiento farmacológico , Tuberculosis Pulmonar/diagnóstico , Tuberculosis Pulmonar/tratamiento farmacológico
20.
Artículo en Inglés | MEDLINE | ID: mdl-35849824

RESUMEN

Polymer semiconductors with large elastic recovery (ER) under high strain in thin film state are highly desirable for stretchable electronics. Here we report a type of stretchable semiconductor PU(DPP)x, by copolymerization of oligodiketopyrrolopyrrole-based conjugated block and hydrogenated polybutadiene flexible block via urethane linkage for intermolecular hydrogen bonding. By regulating block ratio, PU(DPP)35 with 35 wt % conjugated block exhibits high intrinsic ER > 80% under 175% strain (ε) in pseudo free-standing thin film state, comparable with commercial elastomers, and crack onset strain (COS) > 300% along with maximum hole mobility of 0.19 cm2 V-1 s-1 in organic thin film transistors to bring it to the best performing block copolymer-type stretchable semiconductors. Enhanced mobility is achieved using PU(DPP)35 as the binder for conjugated polymer PDPPT3. The 25 wt %-PDPPT3 blend displays mobility up to 1.28 cm2 V-1 s-1 along with COS ∼120%, and 10 wt %-PDPPT3 blend exhibits ER of 78% at ε = 150%, COS of ∼230%, modulus of 36.5 MPa, maximum mobility of 0.62 cm2 V-1 s-1 and no obvious degradation of mobility at ε = 150% after 100 cycles of strain. Moreover, the structural similarity enables the blend film uniform and stable microstructure against mechanical and thermal deformation. Notably, PU(DPP)35 and the blend are characterized by high mechanical performance similar to that of commercial elastomers in thin film state, and demonstrate their potential for high performance stretchable electronics.

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