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1.
Cardiol Young ; : 1-6, 2024 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-38577783

RESUMO

OBJECTIVE: Head-up tilt test (HUTT) is an important tool in the diagnosis of pediatric vasovagal syncope. This research will explore the relationship between syncopal symptoms and HUTT modes in pediatric vasovagal syncope. METHODS: A retrospective analysis was performed on the clinical data of 2513 children aged 3-18 years, who were diagnosed with vasovagal syncope, from Jan. 2001 to Dec. 2021 due to unexplained syncope or pre-syncope. The average age was 11.76 ± 2.83 years, including 1124 males and 1389 females. The patients were divided into the basic head-up tilt test (BHUT) group (596 patients) and the sublingual nitroglycerine head-up tilt test (SNHUT) group (1917 patients) according to the mode of positive HUTT at the time of confirmed pediatric vasovagal syncope. RESULTS: (1) Baseline characteristics: Age, height, weight, heart rate (HR), systolic blood pressure (SBP), diastolic blood pressure (DBP), and composition ratio of syncope at baseline status were higher in the BHUT group than in the SNHUT group (all P < 0.05). (2) Univariate analysis: Age, height, weight, HR, SBP, DBP, and syncope were potential risk factors for BHUT positive (all P < 0.05). (3) Multivariate analysis: syncope was an independent risk factor for BHUT positive, with a probability increase of 121% compared to pre-syncope (P<0.001). CONCLUSION: The probability of BHUT positivity was significantly higher than SNHUT in pediatric vasovagal syncope with previous syncopal episodes.

2.
Molecules ; 29(7)2024 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-38611832

RESUMO

In order to expand the application of bismuth vanadate (BiVO4) to the field of photoelectrochemistry, researchers have explored the potential of BiVO4 in catalyzing or degrading organic substances, potentially presenting a green and eco-friendly solution. A study was conducted to investigate the impact of electrolytes on the photocatalysis of benzyl alcohol by BiVO4. The research discovered that, in an acetonitrile electrolyte (pH 9) with sodium bicarbonate, BiVO4 catalyzed benzyl alcohol by introducing saturated V5+. This innovation addressed the issue of benzyl alcohol being susceptible to catalysis in an alkaline setting, as V5+ was prone to dissolution in pH 9 on BiVO4. The concern of the photocorrosion of BiVO4 was mitigated through two approaches. Firstly, the incorporation of a non-aqueous medium inhibited the formation of active material intermediates, reducing the susceptibility of the electrode surface to photocorrosion. Secondly, the presence of saturated V5+ further deterred the leaching of V5+. Concurrently, the production of carbonate radicals by bicarbonate played a vital role in catalyzing benzyl alcohol. The results show that, in this system, BiVO4 has the potential to oxidize benzyl alcohol by photocatalysis.

3.
Adv Mater ; : e2311692, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38619834

RESUMO

This comprehensive review delves into the intricacies of the photoelectrochemical (PEC) water splitting process, specifically focusing on the design, fabrication, and optimization of particle-based photoelectrodes for efficient green hydrogen production. These photoelectrodes, composed of semiconductor materials, potentially harness light energy and generate charge carriers, driving water oxidation and reduction reactions. The versatility of particle-based photoelectrodes as a platform for investigating and enhancing various semiconductor candidates is explored, particularly the emerging complex oxides with compelling charge transfer properties. However, the challenges presented by many factors influencing the performance and stability of these photoelectrodes, including particle size, shape, composition, morphology, surface modification, and electrode configuration, are highlighted. The review introduces the fundamental principles of semiconductor photoelectrodes for PEC water splitting, presents an exhaustive overview of different synthesis methods for semiconductor powders and their assembly into photoelectrodes, and discusses recent advances and challenges in photoelectrode material development. It concludes by offering promising strategies for improving photoelectrode performance and stability, such as the adoption of novel architectures and heterojunctions. This article is protected by copyright. All rights reserved.

4.
Nature ; 627(8003): 313-320, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38480964

RESUMO

Intrinsically stretchable electronics with skin-like mechanical properties have been identified as a promising platform for emerging applications ranging from continuous physiological monitoring to real-time analysis of health conditions, to closed-loop delivery of autonomous medical treatment1-7. However, current technologies could only reach electrical performance at amorphous-silicon level (that is, charge-carrier mobility of about 1 cm2 V-1 s-1), low integration scale (for example, 54 transistors per circuit) and limited functionalities8-11. Here we report high-density, intrinsically stretchable transistors and integrated circuits with high driving ability, high operation speed and large-scale integration. They were enabled by a combination of innovations in materials, fabrication process design, device engineering and circuit design. Our intrinsically stretchable transistors exhibit an average field-effect mobility of more than 20 cm2 V-1 s-1 under 100% strain, a device density of 100,000 transistors per cm2, including interconnects and a high drive current of around 2 µA µm-1 at a supply voltage of 5 V. Notably, these achieved parameters are on par with state-of-the-art flexible transistors based on metal-oxide, carbon nanotube and polycrystalline silicon materials on plastic substrates12-14. Furthermore, we realize a large-scale integrated circuit with more than 1,000 transistors and a stage-switching frequency greater than 1 MHz, for the first time, to our knowledge, in intrinsically stretchable electronics. Moreover, we demonstrate a high-throughput braille recognition system that surpasses human skin sensing ability, enabled by an active-matrix tactile sensor array with a record-high density of 2,500 units per cm2, and a light-emitting diode display with a high refreshing speed of 60 Hz and excellent mechanical robustness. The above advancements in device performance have substantially enhanced the abilities of skin-like electronics.


Assuntos
Desenho de Equipamento , Pele , Transistores Eletrônicos , Dispositivos Eletrônicos Vestíveis , Humanos , Silício , Nanotubos de Carbono , Tato
5.
Foods ; 13(6)2024 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-38540948

RESUMO

Bifidobacterium longum is a common probiotic; both viable and heat-inactivated Bifidobacterium longum have many probiotic effects, such as anticancer effects. But some mechanisms of anticancer effects are still unclear, especially for heat-inactivated probiotics. In this study, we analyzed the effects of viable and heat-inactivated Bifidobacterium longum D42 on human colon cancer cells (HT-29). Cell proliferation, membrane permeability and apoptosis were detected by using the CCK-8 method, LDH method and Annexin V-FITC/PI kits. The ROS level and mitochondrial membrane potential were examined using the fluorescent probes DCFH-DA and JC-1. Real-time fluorescence quantitative PCR (RT-qPCR) and Western blot were used to detect the expression of mitochondrial apoptosis pathway genes and proteins. The results showed that viable and heat-inactivated Bifidobacterium longum D42 at concentrations of 1 × 106 CFU/mL significantly inhibited the proliferation of and increased the level of LDH release of HT-29 colon cancer cells. We found that they could increase the apoptosis rate of HT-29 cells. Moreover, they could also induce apoptosis by inducing cells to produce ROS and destroying the mitochondrial membrane potential of cells. Further studies found that they could increase the mRNA transcription and protein expression levels of the Caspase-3, Caspase-9 and Bax genes in cells, and reduce the mRNA transcription and protein expression levels of the Bcl-2 gene. In summary, our findings revealed that viable and heat-inactivated Bifidobacterium longum D42 have inhibitory effects on proliferation and promote the apoptosis of human colon cancer cells, and also have certain adjuvant drug therapeutic effects and have potential application value in the adjuvant treatment of colon cancer.

6.
ACS Appl Mater Interfaces ; 15(48): 55957-55964, 2023 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-37992220

RESUMO

The high device density and fabrication complexity have hampered the development of the electronics. The advanced designs, which could implement the functions of the circuits with higher device density but less fabrication complexity, are hence required. Meanwhile, the MoS2-based devices have recently attracted considerable attention owing to their advantages such as the ultrathin thickness. However, the MoS2-based multifunctional multigate one-transistor (MGT) designs with logic-in-memory and artificial synaptic functions have rarely been reported. Here, an MGT structure based on the MoS2 channel is proposed, with both the logic-in-memory and artificial synaptic behaviors and with more controllable processes than the manual transfer. The proposed MoS2-based MGT functions could be attributed to the semijunction mechanism and enhanced effect of the additional terminals with improved controllability. This study is the first to demonstrate that the neuromorphic computing, logic gate, and memory functions can all be achieved in a MoS2 MGT device without using any additional layers or plasticity to a transistor. The reported results provide a new strategy for developing brain-like systems and next-generation electronics using multifunctional designs and ultrathin materials.

7.
J Environ Manage ; 345: 118810, 2023 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-37595461

RESUMO

Vegetation concrete has been widely applied for the ecological restoration of bare steep slopes in short-term frozen and non-frozen soil regions in China. However, field experiments conducted in seasonally frozen soil regions have revealed decreases in the bulk density, nutrient content and vegetation coverage. This study aimed to clarify the evolution process and mechanism of the engineering properties of vegetation concrete under atmospheric freeze-thaw (F-T) test conditions. The physical, mechanical, and nutrient properties of vegetation concrete were investigated using six F-T cycles (0, 1, 2, 5, 10 and 20) and two initial soil water contents (18 and 22%). The results revealed decreases in the acoustic wave velocity and cohesive forces and an increase in the permeability coefficient of the vegetation concrete owing to F-T action. X-ray diffraction tests indicated that the decreased cohesive force was closely related to the overall decrease in the content of gelling hydration products in the vegetation concrete. Additionally, the contents of NH4+-N, PO43-P and K+ in the vegetation concrete increased, whereas that of NO3--N decreased. The loss rates of these soluble nutrients increased, indicating that the nutrient retention capacity of the vegetation concrete had decreased. Specifically, the decreased nutrient retention capacity was mainly related to the disintegration and fragmentation of larger aggregates due to F-T action. This study provides theoretical support for future research on improving the anti-freezing capability of ecological slope protection substrates in seasonally frozen soil regions.


Assuntos
Solo , Água , Solo/química , Clima , Engenharia , China
8.
Nat Nanotechnol ; 18(10): 1175-1184, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37322142

RESUMO

Stretchable polymer semiconductors (PSCs) are essential for soft stretchable electronics. However, their environmental stability remains a longstanding concern. Here we report a surface-tethered stretchable molecular protecting layer to realize stretchable polymer electronics that are stable in direct contact with physiological fluids, containing water, ions and biofluids. This is achieved through the covalent functionalization of fluoroalkyl chains onto a stretchable PSC film surface to form densely packed nanostructures. The nanostructured fluorinated molecular protection layer (FMPL) improves the PSC operational stability over an extended period of 82 days and maintains its protection under mechanical deformation. We attribute the ability of FMPL to block water absorption and diffusion to its hydrophobicity and high fluorination surface density. The protection effect of the FMPL (~6 nm thickness) outperforms various micrometre-thick stretchable polymer encapsulants, leading to a stable PSC charge carrier mobility of ~1 cm2 V-1 s-1 in harsh environments such as in 85-90%-humidity air for 56 days or in water or artificial sweat for 42 days (as a benchmark, the unprotected PSC mobility degraded to 10-6 cm2 V-1 s-1 in the same period). The FMPL also improved the PSC stability against photo-oxidative degradation in air. Overall, we believe that our surface tethering of the nanostructured FMPL is a promising approach to achieve highly environmentally stable and stretchable polymer electronics.

9.
Oral Surg Oral Med Oral Pathol Oral Radiol ; 135(5): e108-e113, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36697296

RESUMO

FET (encompassing both EWSR1 and FUS) fusions with genes from the CREB family (CREB1, ATF1, and CREM) are involved in a variety of neoplasms. Recently, FET::CREB fusions were recognized in a group of malignant epithelioid neoplasm with a striking predilection to mesothelial-lined cavities and frequent cytokeratin immunoexpression. Herein, we report a rare mesenchymal neoplasm with epithelioid morphology and nonspecific immunoprofile harboring a FUS::CREM fusion arising in the oral tongue of a 53-year-old man. Histology showed a well-circumscribed tumor composed of epithelioid cells with eosinopohilic or clear cytoplasm with sparse stroma, accompanied by peripheral lymphoplasmacytic infiltrates. Immunohistochemically, an extensive panel revealed only patchy expression of synaptophysin and weak-to-moderate nuclear expression of TFE3, and negativity for other markers including cytokeratins, epithelial membrane antigen, p63/p40, vimentin, S100, smooth muscle actin, CD34, desmin, SOX10, glial fibrillary acidic protein, melan-A, HMB45, and CD68. A FUS::CREM gene fusion was detected by next generation sequencing at an outside institution, and subsequent fluorescence in situ hybridization analysis confirmed the presence of FUS gene rearrangement. The identification and analysis of additional cases should help to clarify the nosologic status and the biologic potential of this tumor.


Assuntos
Fusão Gênica , Neoplasias de Tecidos Moles , Masculino , Humanos , Pessoa de Meia-Idade , Hibridização in Situ Fluorescente , Neoplasias de Tecidos Moles/patologia , Modulador de Elemento de Resposta do AMP Cíclico/genética , Modulador de Elemento de Resposta do AMP Cíclico/metabolismo , Proteína FUS de Ligação a RNA/genética , Proteína FUS de Ligação a RNA/metabolismo
10.
Small ; 19(11): e2206763, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36599667

RESUMO

To fabricate a high-efficiency bulk-heterojunction (BHJ)-based photocathode, introducing suitable interfacial modification layer(s) is a crucial strategy. Surface engineering is especially important for achieving high-performance photocathodes because the photoelectrochemical (PEC) reactions at the photocathode/electrolyte interface are the rate-limiting process. Despite its importance, the influence of interfacial layer morphology regulation on PEC activity has attracted insufficient attention. In this work, RuO2 , with excellent conductivity, capacity and catalytic properties, is utilized as an interfacial layer to modify the BHJ layer. However, the homogeneous coverage of hydrophilic RuO2 on the hydrophobic BHJ surface is challenging. To address this issue, a Pt nanoparticle-assisted homogeneous RuO2 layer deposition method is developed and successfully applied to several BHJ-based photocathodes, achieving superior PEC performance compared to those prepared by conventional interface engineering strategies. Among them, the fluorine-doped tin oxide (FTO)/J71:N2200(Pt)/RuO2 photocathode generates the best photocurrent density of -9.0 mA cm-2 at 0 V with an onset potential of up to 1.0 V under AM1.5 irradiation.

11.
Small ; 19(6): e2205244, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36436884

RESUMO

Liquid-crystal small molecule donor (LC-SMD) is a new type organic semiconductor, which is attractive not only for the easy synthesis and purification, well-defined chemical structures, etc., but also for the LC state that makes the crystallinity and aggregation state of molecules adjustable. Here, one new LC-SMD (a-BTR-H4) is synthesized with 1D alkoxyl and 2D thiophene-alkylthiol side-chained benzo[1,2-b:4,5-b']dithiophene core, trithiophene π-bridge, and 3-(2-ethylhexyl) rhodanine end group. a-BTR-H4 shows low LC transition temperature, 117 °C, however, counterpart material (a-BTR-H5) with the same main structure but 3-ethyl rhodanine terminal group does not show LC properties. Although a-BTR-H4/H5 show similar Ultraviolet-visible absorption spectrum and energy levels, a-BTR-H4 affords relatively high photovoltaic performances due to favorable blend morphology produced by the consistent annealing temperature of Y6-based accepters and liquid crystal temperature of donors. Preliminary results indicate that a-BTR-H4 gains a power conversion efficiency (PCE) of 11.36% for Y6-based devices, which is ascribed to better light harvest as well as balanced carrier generation and transport, while a-BTR-H5 obtains 7.57% PCE. Therefore, some materials with unique nematic LC phase have great application potential in organic electronics, and further work to utilize a-BTR-H4 for high-performance device is underway.

12.
Front Immunol ; 13: 947755, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36091059

RESUMO

The intestine is the largest digestive and immune organ in the human body, with an intact intestinal mucosal barrier. Bifidobacterium longum is the specific gut commensals colonized in the human gut for boosting intestinal immunity to defend against intestinal mucosal immune injury. In the LPS-induced intestinal injury model, the Bifidobacterium longum BL-10 was suggested to boost the intestinal immune. Detailly, compared with the LPS-induced mice, the BL10 group significantly reduced intestine (jejunum, ileum, and colon) tissue injury, pro-inflammatory cytokines (TNF-α, IFN-γ, IL-2, IL-6, IL-17, IL-22, and IL-12) levels and myeloperoxidase activities. Moreover, the B. longum BL-10 significantly increased the number of immunocytes (CD4+ T cells, IgA plasma cells) and the expression of tight junction protein (Claudin1 and Occludin). B. longum BL-10 regulated the body's immune function by regulating the Th1/Th2 and Th17/Treg balance, which showed a greater impact on the Th1/Th2 balance. Moreover, the results also showed that B. longum BL-10 significantly down-regulated the intestinal protein expression of TLR4, p-IκB, and NF-κB p65. The B. longum BL-10 increased the relative abundance of the genera, including Lachnospiraceae_NK4A136_group and Clostridia_UCG-014, which were related to declining the levels of intestinal injury. Overall, these results indicated that the B. longum BL-10 had great functionality in reducing LPS-induced intestinal mucosal immune injury.


Assuntos
Bifidobacterium longum , Animais , Humanos , Imunidade , Imunomodulação , Mucosa Intestinal , Lipopolissacarídeos/farmacologia , Camundongos
13.
J Craniofac Surg ; 33(8): 2650-2652, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36000745

RESUMO

BACKGROUND: Surgical resection through extraoral approach is the first choice for submental mass but leaves a visible scar. This study introduces an endoscopy-assisted transoral approach to resect submental mass and evaluates the clinical results. PATIENTS AND METHODS: From September 2018 to December 2019, 5 patients with submental mass underwent surgical resection through endoscopy-assisted transoral approach. The swallowing, speech, and appearance domains of the University of Washington Quality of Life questionnaire were assessed preoperatively and at 3 months postoperatively. RESULTS: Each mass was completely removed without rupture. No patient developed any permanent postoperative complications. The function and aesthetic outcomes were excellent without recurrence. CONCLUSIONS: Endoscopy-assisted transoral approach for resection of submental mass is a reliable technique that achieves excellent postoperative aesthetics and functional results.


Assuntos
Estética Dentária , Qualidade de Vida , Humanos , Endoscopia/métodos
14.
J Agric Food Chem ; 70(28): 8680-8692, 2022 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-35797025

RESUMO

Bifidobacterium longum is frequently utilized and has broad prospects for preventing liver injury. The current research assessed the antioxidant capacity of B. longum BL-10 and probed its mechanism for ameliorating lipopolysaccharide (LPS)-induced acute liver injury (ALI). B. longum BL-10-encoded 15 antioxidant genes showed strong reducing power activity and scavenging activity of DPPH, hydroxyl radicals, and superoxide anions. The intragastric administration of B. longum BL-10 resulting in a marked reduction in liver function indicators (alanine aminotransferase, aspartate aminotransferase, total bilirubin, and total bile acid) and proinflammatory cytokines (TNF-α, IFN-γ, and IL-6) was indicative of ALI recovery. Following 16s RNA analysis, B. longum BL-10 significantly altered the richness of genera, as for the Escherichia-Shigella, Lachnospiraceae_NK4A136_group, and Clostridia_UCG-014, dramatically contributing to the formation of acetic acid and butyric acid. Meanwhile, their metabolites regulated the TLR4/NF-κB signaling pathways to alleviate hepatic injury symptoms. Overall, all the results demonstrated that B. longum BL-10 had excellent efficiency in preventing LPS-induced ALI.


Assuntos
Antioxidantes , Bifidobacterium longum , Doença Hepática Induzida por Substâncias e Drogas , Animais , Doença Hepática Induzida por Substâncias e Drogas/terapia , Lipopolissacarídeos/efeitos adversos , Fígado/metabolismo , Camundongos , NF-kappa B/genética , NF-kappa B/metabolismo
15.
Sci Total Environ ; 838(Pt 4): 156446, 2022 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-35660577

RESUMO

Under freeze-thaw conditions, the substrates used for ecological protection degrade, which involves decreases in compactness and fertiliser retention ability. As such, our purpose in this study was to use two typical types of activated carbon (AC), wood-based activated carbon (WAC) and coal-based activated carbon (CAC), to enhance the antifrost property of vegetation concrete (VC). We investigated the effects of five different proportions of planting soil weight (0.5 %, 1 %, 2 %, 4 %, and 6 %) mixed in each type of AC to determine their influence on the physical, mechanical, chemical, and biological properties of VC. The VC samples prepared without AC were used as control check (CK). The results showed that AC addition effectively enhanced the nutrient retention and microorganism capacity of VC under freeze-thaw conditions (10 and 60 freeze-thaw cycles). The leaching loss rate of ammonium nitrogen (NH4+-N) decreased to 31.98 % for WAC-6 %-60 from 46.87 % for CK-60, and the microorganism biomass carbon (MBC) increased to 138.54 mg·kg-1 for WAC-6 %-60 from 103.52 mg·kg-1 for CK-60. However, we observed some negative effects, including decreases in the cohesion and internal friction angle. In addition, the water holding capacity and matric suction first increased and then decreased as the proportion of AC mixed in the VC increased, with a turning point of approximately 2 %. By comprehensively considering previous VC eco-restoration technology study results, the recommended mixing amount of AC is 1 %-2 %, which would take full advantage of the benefits of AC and ensure that any negative effect of its use falls within an acceptable range. In addition, WAC generally performed better than CAC, but the aging rate of the former was faster than that of the latter according to scanning electron microscopy (SEM) images and dissolved organic carbon (DOC) analysis. From our results, we concluded that incorporating AC into VC improves the suitability of VC when applied in freeze-thaw conditions.


Assuntos
Carvão Vegetal , Solo , Fertilidade , Congelamento , Nitrogênio/metabolismo , Solo/química
16.
Food Funct ; 13(9): 4914-4929, 2022 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-35395665

RESUMO

The intestine is the largest digestive and immune organ in the human body, with an intact intestinal mucosal barrier. Lactobacillus plantarum is an important strain of probiotics in the intestine for boosting intestinal immunity to defend against intestinal injury. In the lipopolysaccharide-induced intestinal injury model, mixed L. plantarum (L. plantarum KLDS 1.0318, L. plantarum KLDS 1.0344, and L. plantarum KLDS 1.0386) was suggested to boost intestinal immunity. In detail, compared with LPS-induced mice, mice in the mixed L. plantarum group showed significantly reduced intestine (jejunum, ileum, and colon) tissue injury, pro-inflammatory cytokine (TNF-α, IL-6 and IL-12) levels, myeloperoxidase activities, and serum D-lactate (P < 0.05) content. Moreover, the mixed L. plantarum significantly increased the number of immunocytes (CD4+ T cells, IgA plasma cells) and the expression of tight junction proteins (Claudin1 and Occludin). The results also showed that the mixed L. plantarum significantly down-regulated (P < 0.05) the intestinal protein expression of TLR4, p-IκB, and NF-κB p65. The mixed L. plantarum group increased the relative abundance of the genera, including Lactobacillus, Lachnoclostridium, and Desulfovibrio, which are related to improving the levels of SCFAs (acetic acid, butyric acid) and total bile acid (P < 0.05). Overall, these results indicated that the mixed L. plantarum had great functionality in reducing LPS-induced intestinal injury.


Assuntos
Enteropatias , Lactobacillus plantarum , Probióticos , Animais , Enteropatias/metabolismo , Mucosa Intestinal/metabolismo , Lipopolissacarídeos/efeitos adversos , Lipopolissacarídeos/metabolismo , Camundongos
17.
Front Chem ; 10: 832342, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35273948

RESUMO

The photocathodes are essential in photoelectrochemical systems for harvesting solar energy as green fuels. However, the light-absorbing p-type semiconductor in them usually suffers from carrier recombination issues. An effective strategy to address it is fabricating the p-n heterojunction to create an interfacial electric field. However, plenty of deposition process of the n-type layer for this purpose requires either sophisticated instruments or subsequent treatments, which may damage the vulnerable p-type structure. Herein, we report a mild approach for a ready-to-use n-type layer with full functionality. Structural analyses proved the successful coating of a uniform titania layer (up to 40 nm) over Cu2O without damaging its structure. Owing to the high Ti3+ content, the layer possesses excellent charge transport ability and requires no additional annealing. The heterojunction effectively facilitates the carrier separation and positively shifts the photocurrent onset potential for 0.2 V. The Mott-Schottky plot and the impedance study reveal an enhanced carrier collection with reduced charge transfer resistances. Such a nano-heterojunction can be further loaded with the hydrogen evolution catalyst, which almost doubles the photocurrent with an extended lifetime than that of the pristine Cu2O nanoarray. This approach puts forward a potentially scalable and efficient choice for fabricating photoelectrochemical devices.

18.
Small ; 17(52): e2104307, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34725925

RESUMO

Cost-effective photoanodes with remarkable electronic properties are highly demanded for practical photoelectrochemical (PEC) water splitting. The ability to manipulate the surface carrier separation and recombination is pivotal for achieving high PEC performance for water splitting. Here, a facile and economical approach is reported for substantially improving the surface charge separation property of CdS photoanodes through in situ photoactivation, which significantly reduces surface charge recombination through the formation of thiosulfate ion which is favorable to the transfer of photogenerated holes and a uniform nanoporous morphology via the dissolving Cd2+ with phosphate ions on the surface of CdS. The resulting CdS electrodes through scalable particle transfer method exhibit nearly tripled photocurrents, with an incident-photon-to-current conversion efficiency (IPCE) at 480 nm exceeding 80% at 0.6 V versus reversible hydrogen electrode (RHE). And the CdS thin films prepared from chemical bath deposition display quadrupled photocurrents after the stir and PEC activation, with an IPCE of 91.7% at 455 nm and 0.6 V versus RHE. With the suppression of photocorrosion in alkaline borate buffer, the activated photoanodes show great stability for solar hydrogen production at the sacrifice of sulfite. This work brings insights into the design of nanoporous metal sulfide semiconductors for solar water splitting.

19.
Front Microbiol ; 12: 756519, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34795651

RESUMO

Increasing evidence has indicated that oxidative stress is associated with the health of infants. Bifidobacterium, especially B. longum subsp. longum strains, are abundant in the gut microbiota of infants, which may have the potential to ameliorate oxidative damage. Thus, this study aimed to isolate and screen B. longum subsp. longum strains with probiotic characters and antioxidant properties as infants' dietary supplements. In this study, 24 B. longum subsp. longum strains were isolated from 15 healthy infants identified via 16S rRNA and heat shock protein 60 (hsp60) sequences. B. longum subsp. longum B13, F2, K4, K5, K10, K13, and K15 strains were selected based on high values obtained from autoaggregation, hydrophobicity, and adhesion assays to HT-29 cells. Among these seven strains, B. longum subsp. longum F2, K5, K10, and K15 were selected according to the high tolerance of gastrointestinal tract conditions compared to Bifidobacterium animalis subsp. lactis BB-12. Among these four strains, B. longum subsp. longum K5 was susceptible to common antibiotics and showed the highest intestinal epithelial cell proliferation of CCD 841 CoN. Additionally, B. longum subsp. longum K5 showed a strong antioxidant capacity, and its supernatant exhibited better activity of reducing power, hydroxyl radical scavenging, and DPPH radical scavenging than that of the intact cells with cell-free extracts. The findings indicated that B. longum subsp. longum K5 could be used as a probiotic candidate in infant nutrition.

20.
Materials (Basel) ; 14(21)2021 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-34772245

RESUMO

Asymmetric molecule strategy is considered an effective method to achieve high power conversion efficiency (PCE) of polymer solar cells (PSCs). In this paper, nine oligomers are designed by combining three new electron-deficient units (unitA)-n1, n2, and n3-and three electron-donating units (unitD)-D, E, and F-with their π-conjugation area extended. The relationships between symmetric/asymmetric molecule structure and the performance of the oligomers are investigated using the density functional theory (DFT) and time-dependent density functional theory (TD-DFT) calculations. The results indicate that asymmetry molecule PEn2 has the minimum dihedral angle in the angle between two planes of unitD and unitA among all the molecules, which exhibited the advantages of asymmetric structures in molecular stacking. The relationship of the values of ionization potentials (IP) and electron affinities (EA) along with the unitD/unitA π-extend are revealed. The calculated reorganization energy results also demonstrate that the asymmetric molecules PDn2 and PEn2 could better charge the extraction of the PSCs than other molecules for their lower reorganization energy of 0.180 eV and 0.181 eV, respectively.

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