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1.
Nature ; 632(8025): 528-535, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-39048826

RESUMEN

Conjugated polymers promise inherently flexible and low-cost thermoelectrics for powering the Internet of Things from waste heat1,2. Their valuable applications, however, have been hitherto hindered by the low dimensionless figure of merit (ZT)3-6. Here we report high-ZT thermoelectric plastics, which were achieved by creating a polymeric multi-heterojunction with periodic dual-heterojunction features, where each period is composed of two polymers with a sub-ten-nanometre layered heterojunction structure and an interpenetrating bulk-heterojunction interface. This geometry produces significantly enhanced interfacial phonon-like scattering while maintaining efficient charge transport. We observed a significant suppression of thermal conductivity by over 60 per cent and an enhanced power factor when compared with individual polymers, resulting in a ZT of up to 1.28 at 368 kelvin. This polymeric thermoelectric performance surpasses that of commercial thermoelectric materials and existing flexible thermoelectric candidates. Importantly, we demonstrated the compatibility of the polymeric multi-heterojunction structure with solution coating techniques for satisfying the demand for large-area plastic thermoelectrics, which paves the way for polymeric multi-heterojunctions towards cost-effective wearable thermoelectric technologies.

2.
Exp Dermatol ; 32(2): 135-145, 2023 02.
Artículo en Inglés | MEDLINE | ID: mdl-36251463

RESUMEN

Psoriasis is a chronic recurrent inflammatory skin disease that is characterized by abnormal proliferation and differentiation of keratinocytes (KCs), angiogenesis and skin inflammation. Transfer RNA fragments (tRFs) are tRNA-derived small RNAs (tsRNAs), which possess regulatory functions in many diseases. Their potential roles in the pathological development of psoriasis have not been established. We first identified differentially expressed (DE) tRFs from psoriatic skin lesions using small RNA sequencing, and collected additional clinical samples for validation. Then, we investigated the function and mechanism of target tRFs in vitro. As a result of our investigation: we identified 234 DE transcripts in psoriatic skin lesions compared with normal controls. Further functional analysis showed the downregulation of tRF-Ile-AAT-019 in psoriatic lesions plays a critical role in pathogenesis since it could target 3'UTR of the serine protease serpin protein E1 (SERPINE1) gene. We next demonstrated that tRF-Ile-AAT-019 could suppress SERPINE1, thus leading to decreased expressions of vascular endothelial growth factor but increased expressions of keratinocytes (KCs) differentiation markers including Keratin1 and Involucrin. In conclusion, tRF-Ile-AAT-019 plays a protective role in the pathological progression of psoriasis via targeting SERPINE1, resulting in regulation of KCs differentiation and vascular proliferation biomarkers and providing a potential novel targeting pathway for the disease treatment.


Asunto(s)
Psoriasis , ARN , Humanos , Factor A de Crecimiento Endotelial Vascular/metabolismo , ARN de Transferencia/genética , ARN de Transferencia/metabolismo , Regulación hacia Abajo
3.
AAPS PharmSciTech ; 24(1): 36, 2023 Jan 12.
Artículo en Inglés | MEDLINE | ID: mdl-36635447

RESUMEN

The current study aimed to improve the poor solubility of albendazole (ABZ) by means of phospholipid complexation, hence to improve its oral bioavailability. The solvent-evaporation method for ABZ-phospholipid complex (ABZ-PC) preparation was established for the first time. And a systematic optimization of preparation conditions of ABZ-PC was performed. Physicochemical studies of ABZ-PC were performed with FTIR, DSC, and XRD measurements to confirm the formation of the ABZ-PC and reveal the interaction mechanism between ABZ and phospholipid molecules. Solubility determination and morphological characterization were applied to verify the solubility improvement of prepared ABZ-PC. Moreover, the pharmacokinetic performance of ABZ-PC was further evaluated in vivo compared with raw materials of ABZ. Under optimal preparation conditions, the AE of ABZ-PC could be approximately 100%. Physicochemical studies indicated that the P = O group in the phospholipid molecule would interact with the N-H group in the ABZ molecule through hydrogen bonds and ABZ was dispersed in an amorphous state after being prepared into ABZ-PC. The aqueous solubility of ABZ-PC in deionized water (pH7.0) improved by 30-folds than free ABZ, and the AUC0-t of ABZ-PC was significantly increased by 2.32 times in comparison with raw materials of ABZ through oral administration. The current study developed an effective method for the phospholipid complexation of ABZ. With significantly improved solubility in an aqueous environment, the prepared ABZ-PC exhibited improved oral bioavailability and pharmacokinetic characteristics indicating it could be potentially applied in the oral drug delivery of ABZ.


Asunto(s)
Albendazol , Fosfolípidos , Ratas , Animales , Albendazol/química , Disponibilidad Biológica , Ratas Sprague-Dawley , Fosfolípidos/química , Sistemas de Liberación de Medicamentos , Solubilidad , Agua/química , Administración Oral
4.
Int Wound J ; 20(6): 2376-2385, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-36527235

RESUMEN

Ozone is a highly reactive oxidant molecule consisting of triatomic oxygen atoms. Ozone therapy can be achieved using ozonated hydrotherapy, ozonated oil, ozone autohemotherapy, and other innovative dosage forms of ozone products. Ozone is frequently used as a complementary therapy for various cutaneous diseases, including infectious skin diseases, wound healing, eczema, dermatitis, psoriasis, axillary osmidrosis, diabetic foot, and pressure ulcers. In addition, several studies have reported the superior potential of ozone therapy for improving skin and gut microbiomes, as well as antitumour and antiaging treatment. Ozone therapy is an emerging treatment strategy that acts via complex mechanisms, including antioxidant effects, immunomodulatory capacity, and modulation of local microcirculation. Studies assessing the mechanism of ozone have gradually expanded in recent years. This review article aims to summarise and explore the possible molecular biological mechanisms of ozone in cutaneous diseases and provide compelling theoretical evidence for the application of ozone in cutaneous diseases.


Asunto(s)
Ozono , Enfermedades Cutáneas Infecciosas , Enfermedades de la Piel , Humanos , Enfermedades de la Piel/tratamiento farmacológico , Piel , Ozono/uso terapéutico , Cicatrización de Heridas
5.
Pharmacol Res ; 177: 106089, 2022 03.
Artículo en Inglés | MEDLINE | ID: mdl-35065202

RESUMEN

BACKGROUND: Our study sought to investigate the efficacy and safety of bivalirudin versus those of unfractionated heparin (UFH) in patients undergoing extracorporeal membrane oxygenation (ECMO). METHODS: PubMed, EMBASE and Cochrane Library were searched for studies enrolling ECMO patients on bivalirudin and UFH (from inception till July 2021). Meta-analysis was conducted. The I2 statistic and p value were used in measuring heterogeneity, and random effects or fixed-effect model was adopted. The Newcastle-Ottawa Scale was used for the risk of bias assessment. Sensitivity and subgroup analyses were undertaken. We performed Egger's test to evaluate publication bias. RESULTS: Fourteen eligible retrospective observational studies with 1501 subjects were identified. Compared with UFH, bivalirudin significantly reduced the risk of in-circuit thrombosis (OR = 0.44, 95% CI [0.31-0.61], p = 0.000), thrombosis (OR = 0.61, 95% CI [0.45-0.83], p= 0.002) and hospital mortality (OR = 0.78, 95% CI [0.61-0.99], p = 0.04) and had a positive impact on survival ECMO (OR = 1.50, 95% CI [1.04-2.16], p= 0.032). Decrease in risk of bleeding (OR = 0.36, 95% CI [0.14-0.91], p = 0.031) associated with bivalirudin was observed. Sources of heterogeneity were identified, and sensitivity analysis revealed similar results. CONCLUSION: Our meta-analysis suggested that bivalirudin was associated with the decreased risk of in-circuit thrombosis, thrombosis, hospital mortality and bleeding in patients on ECMO and improved survival ECMO, indicating the superiority of bivalirudin to UFH in terms of efficacy and safety.


Asunto(s)
Oxigenación por Membrana Extracorpórea , Trombosis , Adulto , Anticoagulantes/efectos adversos , Niño , Oxigenación por Membrana Extracorpórea/efectos adversos , Hemorragia/inducido químicamente , Heparina/efectos adversos , Hirudinas , Humanos , Fragmentos de Péptidos/efectos adversos , Proteínas Recombinantes/efectos adversos , Estudios Retrospectivos , Trombosis/tratamiento farmacológico , Trombosis/prevención & control , Resultado del Tratamiento
6.
BMC Med Educ ; 21(1): 606, 2021 Dec 09.
Artículo en Inglés | MEDLINE | ID: mdl-34879860

RESUMEN

BACKGROUND: In this study, we applied the small private online course (SPOC) and team-based learning (TBL) blended teaching model to dermatology and venereology to ensure a higher quality learning experience for clinical medical students. METHODS: A total of 52 fifth-grade clinical undergraduates from Xiangya School of Medicine of Central South University were randomly divided into an experimental (n = 26) and a control group (n = 26). In March 2018, we used the SPOC and TBL blended teaching model in the experimental group and explored the effects of innovative teaching in the dermatology and venereology course, compared with the control group receiving the conventional teaching method. We analyzed the two groups' theoretical assessment scores and questionnaire results to evaluate the efficiency of the new pedagogy. RESULTS: Students in the experimental group had a better understanding than the control group of the dermatology and venereology content and higher scores on the case analysis questions in the final theoretical examination. The results revealed that the majority of the experimental group students agreed that the novel teaching model blended with SPOC&TBL helped them significantly stimulate motivation and develop their ability in self-directed learning, independent thinking, literature retrieval, presentation board, teamwork, communication, and systematic clinical thinking. The teaching satisfaction survey of the two groups showed that the students' satisfaction in the experimental group was significantly higher than in the control group (p < 0.05). CONCLUSIONS: The SPOC&TBL teaching model is better than the traditional one in enriching students' professional knowledge and cultivating their comprehensive ability. It can effectively promote educational quality, improve students' learning effects, and enhance their satisfaction. This method has broad application prospects.


Asunto(s)
Dermatología , Estudiantes de Medicina , Venereología , Evaluación Educacional , Humanos , Aprendizaje Basado en Problemas , Enseñanza
7.
Chemistry ; 26(56): 12868-12873, 2020 Oct 06.
Artículo en Inglés | MEDLINE | ID: mdl-32430943

RESUMEN

Metal-bis(dithiolene) is one of the most promising structures showing redox activity, excellent electron transport and magnetic properties as well as catalytic activities. Perthiolated coronene (PTC), an emerging highly symmetric ligand containing the smallest graphene nanoplate was employed to manufacture a hybrid material with fused metal-bis(dithiolene) and graphene nanoplate, and it has been demonstrated as an efficient strategy for the construction of multifunctional materials recently. Herein, Co-PTC, a 2D MOF containing Co-bis(dithiolene) and coronene units is prepared via a homogeneous reaction for the first time as powder samples, which are bar-shaped microparticles composed of nanosheets. A neutral formula of [Co3 (C24 S12 )]n is verified for Co-PTC. Co-PTC plays an ultrahigh conductivity of approximately 45 S cm-1 at room temperature as compressed samples, which is among the highest value ever reported for the compressed powder samples of conducting MOFs. Moreover, Co-PTC exhibits good electrocatalytic performance in the hydrogen evolution reaction (HER) with a Tafel slope of 189 mV decade-1 and an operating overpotential of 227 mV at 10 mA cm-1 with pH=0, as well as a remarkable stability in the extremely acidic aqueous solutions, which is the best hydrogen evolution properties among metal-organic compounds.

8.
Angew Chem Int Ed Engl ; 59(47): 20873-20878, 2020 Nov 16.
Artículo en Inglés | MEDLINE | ID: mdl-32749045

RESUMEN

3D well-crystallized metal-organic frameworks (MOFs), M-THBQ (M=Fe, Co, Mn, THBQ=tetrahydroxybenzoquinone), are synthesized and characterized. Their structures are determined as cubic cell in the group of Pm 3 ‾ from powder X-ray diffraction data, and their properties of electronic, magnetic and spectroscopic are also investigated. They are all semiconductors, and Fe-THBQ exhibits the air-stable n-type thermoelectric characteristic as its Seebeck coefficient reaches -130 µV K-1 , and the electrical conductivity is 2.7×10-4  S cm-1 at 300 K. Additional, M-THBQ are paramagnetic, and the value of Weiss constant of Fe-THBQ is -219.37 K, indicating the existence of robust intramolecular antiferromagnetic exchanges. Meanwhile, they display strong absorption bands in the range of 220 to 1000 nm, suggest M-THBQ could have the potential to become photoabsorbers, and Fe-THBQ exhibits a narrow band gap of 0.63 eV according to the ultraviolet absorption edge spectrum.

9.
Angew Chem Int Ed Engl ; 59(50): 22602-22609, 2020 Dec 07.
Artículo en Inglés | MEDLINE | ID: mdl-32893955

RESUMEN

Conductive coordination polymers (CPs) have potential in a wide range of applications because of their inherent structural and functional diversity. Three electrically conductive CPs (Cux C6 S6 , x=3, 4 or 5.5) derived from the same organic linker (benzenehexathiol) and metal node (copper(I)) were synthesized and studied. Cux C6 S6 materials are organic-inorganic hybrid copper sulfides comprising a π-π stacking structure and cooper sulfur networks. Charge-transport pathways within the network facilitate conductivity and offer control of the Fermi level through modulation of the oxidation level of the non-innocent redox-active ligand. Two Cux C6 S6 (x=4 or 5.5) CPs display high electrical conductivity and they feature a tunable structural topology and electronic structure. Cu4 C6 S6 and Cu5.5 C6 S6 act as degenerate semiconductors. Moreover, Cu5.5 C6 S6 is a p-type thermoelectric material with a ZT value of 0.12 at 390 K, which is a record-breaking performance for p-type CPs.

10.
J Am Chem Soc ; 140(45): 15153-15156, 2018 Nov 14.
Artículo en Inglés | MEDLINE | ID: mdl-30207157

RESUMEN

Highly crystalline films of a silver-based coordination polymer, [Ag5(C6S6)] n (Ag-BHT, BHT = benzenehexathiol), have been prepared. The structure of Ag-BHT, solved by combining rotation electron diffraction and powder X-ray diffraction techniques, indicates that it has a lamellar structure with alternatively stacked two-dimensional Ag-S networks and layers composed of one-dimensional metal-dithiolene polymers. In addition, the polycrystalline Ag-BHT film shows high electrical conductivity of up to 250 S·cm-1 at 300 K. The ultraviolet-photoelectron spectroscopy and electronic band structure calculations reveal that this can be attributed to the partially filled valence band and the unique two-dimensional Ag-S networks.

11.
Macromol Rapid Commun ; : e1800283, 2018 Jul 05.
Artículo en Inglés | MEDLINE | ID: mdl-29975438

RESUMEN

Polythiophene (PTh) with highly regular molecular structure is synthesized as nearly amorphous thin films by electrochemical methods in a BFEE/DTBP mixed medium (BFEE = boron fluoride ethyl ether; DTBP = 2,6-di-tert-butypyridine). The doping level and film morphology of PTh are modulated through adjusting the current density applied during the polymerization process. A combined analysis with solid-state NMR, FT-IR, and Raman spectra reveals the molecular structural regularity of the resulted PTh films, which leads to the highest electrical conductivity up to 700 S cm-1 for films obtained under an optimized current density of 1 mA cm-2 . By applying the self-heating 3ω-method, thermal conductivities are measured along the in-plane direction. A highly reduced Lorenz number of 6.49 × 10-9 W Ω K-2 and low lattice thermal conductivity of 0.21 W m-1 K-1 were extracted based on the analyses of the electrical and thermal conductivities according to the Wiedemann-Franz Law; the former is about one-third of the Sommerfeld value. Finally, the maximized ZT value can reach up to 0.10 under room temperature, which shows that the highly conducting polymers with less ordered structure is the practical direction for developing organic thermoelectric materials.

12.
Angew Chem Int Ed Engl ; 57(1): 146-150, 2018 01 02.
Artículo en Inglés | MEDLINE | ID: mdl-29160950

RESUMEN

A highly crystalline copper(II) benzenehexathiolate coordination polymer (Cu-BHT) has been prepared. The two-dimensional kagome structure has been confirmed by powder X-ray diffraction, high-resolution transmission electron microscopy, and high-resolution scanning transmission electron microscopy. The as-prepared sample exhibits bulk superconductivity at about 0.25 K, which is confirmed by the zero resistivity, AC magnetic susceptibility, and specific heat measurements. Another diamagnetic transition at about 3 K suggests that there is a second superconducting phase that may be associated with a single layer or few layers of Cu-BHT. It is the first time that superconductivity has been observed in a coordination polymer.

13.
Food Chem ; 444: 138631, 2024 Jun 30.
Artículo en Inglés | MEDLINE | ID: mdl-38325079

RESUMEN

Naringenin (NGE), a typical flavanone abundant in citrus fruits, exhibits remarkable antioxidant activities. However, its low solubility in oil restricts its widespread use in inhibiting lipid oxidation. In this study, we present a novel and effective approach to address this limitation by developing a naringenin-phospholipid complex (NGE-PC COM). Comprehensive analytical techniques including Fourier transform infrared (FTIR), differential scanning calorimetry (DSC), and X-ray diffraction (XRD) were employed to confirm the formation of the NGE-PC COM and elucidate the interaction mechanism between NGE and phospholipids molecules. Notably, the oil-solubility of NGE was significantly enhanced by approximately 2700-fold when formulated as a phospholipid complex in soybean oil. The improved oil-solubility of NGE-PC COM enabled effective inhibition of oil thermal oxidation under high temperature conditions. Generally, this investigation proposed a novel and promising strategy for employing flavanones with strong antioxidant activities to enhance the thermal oxidative stability of edible oil during heating processes.


Asunto(s)
Flavanonas , Fosfolípidos , Fosfolípidos/química , Aceite de Soja , Antioxidantes , Calefacción , Flavanonas/química , Solubilidad , Estrés Oxidativo , Rastreo Diferencial de Calorimetría , Espectroscopía Infrarroja por Transformada de Fourier/métodos , Difracción de Rayos X
14.
Hortic Res ; 11(8): uhae164, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-39108572

RESUMEN

Postharvest decay, primarily caused by pathogenic fungi in ripening fruits and fresh vegetables, poses a challenge to agricultural sustainability and results in significant economic losses. The regulation of the fruit ripening by DNA methylation has been well demonstrated, while defense response of fruit underlying epigenetic regulation against postharvest decay remains uncertain. In the present study, treatment of tomato fruits with the DNA methyltransferase inhibitor 5-Azacytidine (5-Aza) notably decreased their susceptibility to gray mold. Following 5-Aza treatment, we observed a substantial increase in activities of chitinase (CHI) and glucanase (GLU) in tomato fruits, as well as an increase in the expression of the dicer-like SlDCL2 gene family. Suppression of SlDCL2c through double-stranded RNA-induced RNA interference (RNAi) resulted in a decrease in the expression of chitinases CHI3, CHI9, Class V chitinase, and endochitinase 4 by 71%, 29%, 55%, 64%, as well as glucanases Cel1, Cel2, and GluB by 19%, 93%, and 87%, respectively. This was accompanied by decreased activities of resistance-related enzymes, including CHI and GLU. The expression levels of genes phenylalanine ammonia-lyase PAL2, peroxidase POD 12, POD P7, CCR1, CYP84A2, and COMT in phenylpropanoid biosynthesis pathway also decreased by 33%, 53%, 18%, 50%, 30%, and 24% in SlDCL2c-RNAi fruit, resulting in decreased activities of PAL and POD. Consequently, the lesion diameter of gray mold in SlDCL2c-RNAi fruit increased by 55% compared to the control group. Overall, the present study indicated that DNA methyltransferase inhibitor 5-Aza reduces susceptibility of tomato fruit to gray mold through regulation of DCL2c-mediated inducible defense response.

15.
J Fungi (Basel) ; 10(8)2024 Aug 08.
Artículo en Inglés | MEDLINE | ID: mdl-39194887

RESUMEN

Fungi are rich sources of secondary metabolites of agrochemical, pharmaceutical, and food importance, such as mycotoxins, antibiotics, and antitumor agents. Secondary metabolites play vital roles in fungal pathogenesis, growth and development, oxidative status modulation, and adaptation/resistance to various environmental stresses. LaeA contains an S-adenosylmethionine binding site and displays methyltransferase activity. The members of velvet proteins include VeA, VelB, VelC, VelD and VosA for each member with a velvet domain. LaeA and velvet proteins can form multimeric complexes such as VosA-VelB and VelB-VeA-LaeA. They belong to global regulators and are mainly impacted by light. One of their most important functions is to regulate gene expressions that are responsible for secondary metabolite biosynthesis. The aim of this mini-review is to represent the newest cognition of the biosynthetic regulation of mycotoxins and other fungal secondary metabolites by LaeA and velvet proteins. In most cases, LaeA and velvet proteins positively regulate production of fungal secondary metabolites. The regulated fungal species mainly belong to the toxigenic fungi from the genera of Alternaria, Aspergillus, Botrytis, Fusarium, Magnaporthe, Monascus, and Penicillium for the production of mycotoxins. We can control secondary metabolite production to inhibit the production of harmful mycotoxins while promoting the production of useful metabolites by global regulation of LaeA and velvet proteins in fungi. Furthermore, the regulation by LaeA and velvet proteins should be a practical strategy in activating silent biosynthetic gene clusters (BGCs) in fungi to obtain previously undiscovered metabolites.

16.
Front Public Health ; 12: 1310383, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38375338

RESUMEN

Objective: This review aimed to analyze and compare the accuracy of eight screening tools for sarcopenia in older Chinese adults according to different diagnostic criteria. Methods: This systematic review was conducted in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. The PubMed, Embase, Web of Science, China National Knowledge Infrastructure (CNKI), and Wanfang databases were searched between the publication of the first expert consensus on sarcopenia in 2010 and April 2023 using relevant MeSH terms. We evaluated the risk bias of the included studies using the Quality Assessment of Diagnostic Accuracy Studies-2 (QUADAS-2) tool. The pooled result of sensitivity, specificity, positive likelihood ratio (PLR), negative likelihood ratio (NLR), diagnostic odds ratio (DOR), and plot the summary receiver operating characteristic curve (SROC) were calculated by using a bivariate random-effects model. The accuracies of sensitivity and specificity of the screening tools were compared using the Z-test. Results: A total of 30 studies (23,193 participants) were included, except for calf circumference (CC), Ishii, and Finger-ring Test; Screening tools for sarcopenia in older Chinese adults have consistently shown low to moderate sensitivity and moderate to high specificity. Regional and sex differences affect the accuracy of the screening tools. In terms of sensitivity and specificity, the CC, Ishii, and Finger-ring Test were superior to the other screening tools. Conclusion: The Asian Working Group on Sarcopenia (AWGS) 2019 criteria are more appropriate for the diagnosis of sarcopenia in older Chinese adults. According to the AWGS 2019, CC and Ishii are recommended for sarcopenia screening in older Chinese adults.


Asunto(s)
Tamizaje Masivo , Sarcopenia , Sensibilidad y Especificidad , Humanos , Sarcopenia/diagnóstico , China , Anciano , Tamizaje Masivo/normas , Tamizaje Masivo/métodos , Masculino , Femenino , Pueblos del Este de Asia
17.
Adv Mater ; 36(8): e2309679, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38051134

RESUMEN

The ability of n-type polymer thermoelectric materials to tolerate high doping loading limits further development of n-type polymer conductivity. Herein, two alcohol-soluble n-type polythiophene derivatives that are n-PT3 and n-PT4 are reported. Due to the ability of two polymers to tolerate doping loading more significantly than 100 mol%, both achieve electrical conductivity >100 S cm-1 . Moreover, the conductivity of both polythiophenes remains almost constant at high doping concentrations with excellent doping tunability, which may be related to their ability to overcome charging-induced backbone torsion and morphology change caused by saturated doping. The characterizations reveal that n-PT4 has a high doping level and carrier concentration (>3.10 × 1020  cm-3 ), and the carrier concentration continues to increase as the doping concentration increases. In addition, doping leads to improved crystal structure of n-PT4, and the crystallinity does not decrease significantly with increasing doping concentration; even the carrier mobility increases with it. The synergistic effect of these two leads to both n-PT3 and n-PT4 achieving a breakthrough of 100 in conductivity and power factor. The DMlmC-doped n-PT4 achieves a power factor of over 150 µW m-1  K-2 . These values are among the highest for n-type organic thermoelectric materials.

18.
Eur J Radiol Open ; 12: 100564, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38681662

RESUMEN

Background: Respiratory-triggered (RT) and breath-hold are the most common acquisition modalities for magnetic resonance cholangiopancreatography (MRCP). The present study compared the three different acquisition modalities for optimizing the use of MRCP in patients with diseases of the pancreatic and biliary systems. Materials and methods: Three MRCP acquisition modalities were used in this study: conventional respiratory-triggered sampling perfection with application-optimized contrasts using different flip evolutions (RT-SPACE), modified RT-SPACE, and breath-hold (BH)-SPACE. Fifty-eight patients with clinically suspected pancreatic and biliary system disease were included. All image data were acquired on a 1.5 T MR. Scan time and image quality were compared between the three acquisition modalities. Friedman test, which was followed by post-hoc analysis, was performed among triple-scan protocol. Results: There was a significant difference in the mean acquisition time among conventional RT-SPACE, modified RT-SPACE, and BH-SPACE (167.41±32.11 seconds vs 50.84±73.78 seconds vs 18.00 seconds, P <0.001). Signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR) were also significantly different among the three groups (P <0.001). The SNR and CNR were higher in the RT-SPACE group than in the BH-SPACE group (P <0.05). However, there were no statistically significant differences (P >0.05) among the 3 groups regarding quality of overall image, image clarity, background inhibition, and visualization of the pancreatic and biliary system. Conclusions: MRCP acquisition with the modified RT-SPACE sequence greatly shortens the acquisition time with comparable quality images. The MRCP acquisition modality could be designed based on the patient's situation to improve the examination pass rate and obtain excellent images for diagnosis.

19.
Nat Nanotechnol ; 19(8): 1122-1129, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38649746

RESUMEN

Nanoresolved doping of polymeric semiconductors can overcome scaling limitations to create highly integrated flexible electronics, but remains a fundamental challenge due to isotropic diffusion of the dopants. Here we report a general methodology for achieving nanoscale ion-implantation-like electrochemical doping of polymeric semiconductors. This approach involves confining counterion electromigration within a glassy electrolyte composed of room-temperature ionic liquids and high-glass-transition-temperature insulating polymers. By precisely adjusting the electrolyte glass transition temperature (Tg) and the operating temperature (T), we create a highly localized electric field distribution and achieve anisotropic ion migration that is nearly vertical to the nanotip electrodes. The confined doping produces an excellent resolution of 56 nm with a lateral-extended doping length down to as little as 9.3 nm. We reveal a universal exponential dependence of the doping resolution on the temperature difference (Tg - T) that can be used to depict the doping resolution for almost infinite polymeric semiconductors. Moreover, we demonstrate its implications in a range of polymer electronic devices, including a 200% performance-enhanced organic transistor and a lateral p-n diode with seamless junction widths of <100 nm. Combined with a further demonstration in the scalability of the nanoscale doping, this concept may open up new opportunities for polymer-based nanoelectronics.

20.
Shock ; 59(4): 560-568, 2023 04 01.
Artículo en Inglés | MEDLINE | ID: mdl-36719429

RESUMEN

ABSTRACT: Purpose : Sepsis is the leading cause of death in patients with severe acute pancreatitis (SAP) in the intensive care unit (ICU). Early prediction of sepsis secondary to SAP developed in the late phase and of related mortality can enable appropriate treatment and improve outcomes. This study was conducted to evaluate the predictive value of presepsin in ICU patients with SAP at the early stage and compared it with established blood markers and scoring systems. Methods : This retrospective study enrolled 48 septic patients and 53 nonseptic patients admitted to ICU with SAP. Presepsin and other blood markers (procalcitonin, C-reactive protein, IL-6, white blood cell, and serum creatinine) on days 1, 3, and 7 after enrollment as well as scoring systems were assessed to predict secondary sepsis. Outcomes were evaluated at ICU discharge and on days 28 and 90. Results : Presepsin levels (on days 1, 3, and 7) were significantly higher in septic patients than in nonseptic patients. Presepsin levels showed an increasing trend over time in both sepsis and nonsepsis groups, but concentrations increased more rapidly in the sepsis group than in the nonsepsis group. Among the analyzed biomarkers, presepsin was the only blood marker independently associated with sepsis secondary to SAP on days 3 and 7, and presepsin on day 3 was independently associated with mortality at ICU discharge and on days 28 and 90. It showed similar or even better predictive accuracy for both secondary sepsis and mortality than procalcitonin and Sequential Organ Failure Assessment score. Conclusion : Presepsin could be a valuable early predictor of secondary sepsis and mortality in patients admitted to the ICU with SAP and may serve as an indicator for early risk stratification.


Asunto(s)
Pancreatitis , Sepsis , Humanos , Estudios Retrospectivos , Polipéptido alfa Relacionado con Calcitonina , Enfermedad Aguda , Pancreatitis/diagnóstico , Biomarcadores , Unidades de Cuidados Intensivos , Fragmentos de Péptidos , Receptores de Lipopolisacáridos , Pronóstico
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