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1.
Nat Commun ; 15(1): 3187, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38622116

RESUMO

Transcription is crucial for the expression of genetic information and its efficient and accurate termination is required for all living organisms. Rho-dependent termination could rapidly terminate unwanted premature RNAs and play important roles in bacterial adaptation to changing environments. Although Rho has been discovered for about five decades, the regulation mechanisms of Rho-dependent termination are still not fully elucidated. Here we report that Rof is a conserved antiterminator and determine the cryogenic electron microscopy structure of Rho-Rof antitermination complex. Rof binds to the open-ring Rho hexamer and inhibits the initiation of Rho-dependent termination. Rof's N-terminal α-helix undergoes conformational changes upon binding with Rho, and is key in facilitating Rof-Rho interactions. Rof binds to Rho's primary binding site (PBS) and excludes Rho from binding with PBS ligand RNA at the initiation step. Further in vivo analyses in Salmonella Typhimurium show that Rof is required for virulence gene expression and host cell invasion, unveiling a physiological function of Rof and transcription termination in bacterial pathogenesis.


Assuntos
Fator Rho , Fatores de Transcrição , Fatores de Transcrição/metabolismo , Virulência/genética , Fator Rho/genética , Fator Rho/metabolismo , Regulação Bacteriana da Expressão Gênica , Transcrição Gênica , Bactérias/genética , Salmonella typhimurium/genética , Salmonella typhimurium/metabolismo
2.
Food Sci Nutr ; 12(4): 2963-2972, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38628186

RESUMO

This project presents a quantitative detection method to identify raccoon-derived ingredient adulteration in sausage products. The specific copy gene of the raccoon was selected as the target gene. According to the specificity of its primer and probe, the quantitative detection method of raccoon microdrops by droplet digital PCR was established. In addition, the accuracy of the proposed method was verified by artificially mixed samples, and the applicability of this method was tested based on the commercially available products. The experimental results indicate that the raccoon mass (M) and raccoon-extracted DNA concentration have a good linear relationship when the sample content is 5-100 mg, and there is also a significant linear relationship between DNA content and DNA copy number (C) with R 2 = .9982. Therefore, using DNA concentration as the median signal, the conversion equation between raw raccoon mass (M) and DNA copy number (C) could be obtained as follows: M = (C + 177.403)/16.954. The detection of artificially mixed samples and commercial samples shows that the method is accurate and suitable for quantitative adulteration detection of various sausage products in the market.

3.
Front Plant Sci ; 15: 1356922, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38628367

RESUMO

Among the bioactive compounds, lipid-soluble tanshinone is present in Salvia miltiorrhiza, a medicinal plant species. While it is known that ethephon has the ability to inhibit the tanshinones biosynthesis in the S. miltiorrhiza hairy root, however the underlying regulatory mechanism remains obscure. In this study, using the transcriptome dataset of the S. miltiorrhiza hairy root induced by ethephon, an ethylene-responsive transcriptional factor EIN3-like 1 (SmEIL1) was identified. The SmEIL1 protein was found to be localized in the nuclei, and confirmed by the transient transformation observed in tobacco leaves. The overexpression of SmEIL1 was able to inhibit the tanshinones accumulation to a large degree, as well as down-regulate tanshinones biosynthetic genes including SmGGPPS1, SmHMGR1, SmHMGS1, SmCPS1, SmKSL1 and SmCYP76AH1. These are well recognized participants in the tanshinones biosynthesis pathway. Further investigation on the SmEIL1 was observed to inhibit the transcription of the CPS1 gene by the Dual-Luciferase (Dual-LUC) and yeast one-hybrid (Y1H) assays. The data in this work will be of value regarding the involvement of EILs in regulating the biosynthesis of tanshinones and lay the foundation for the metabolic engineering of bioactive ingredients in S. miltiorrhiza.

4.
Immunobiology ; 229(3): 152804, 2024 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-38615511

RESUMO

BACKGROUND: Inducible co-stimulatory factor (ICOS) has a dual role: activating cytotoxic T cells against tumors or exacerbating immunosuppression of regulatory T cells (Tregs) to participate in immune evasion. However, the correlation between ICOS and its co-expression with inhibitory immune checkpoints (IICs) and prognosis in acute myeloid leukemia (AML) is little known. METHODS: The prognostic importance of ICOS and IICs in 62 bone marrow (BM) samples of de novo AML patients from our clinical center (GZFPH) was explored and then the RNA sequencing data of 155 AML patients from the Cancer Genome Atlas (TCGA) database was used for validation. RESULTS: In both GZFPH and TCGA cohorts, high expression of ICOS was significantly associated with poor overall survival (OS) in patients with AML (P < 0.05). Importantly, co-expression of ICOS and PD-1, PD-L1, PD-L2, CTLA-4, and LAG-3 predicted poor OS in AML; among them, ICOS/PD-1 was the optimal combination of immune checkpoints (ICs). The co-expression of ICOS and PD-1 was correlated with poor OS in non-acute promyelocytic leukemia (non-APL) patients following chemotherapy. Additionally, ICOS/PD-1 was an independent OS-predicting factor (P < 0.05). Notably, a nomogram model was constructed by combining ICOS/PD-1, age, European Leukemia Net (ELN) risk stratification, and therapy to visually and personalized predict the 1-, 3-, and 5-year OS of patients with non-APL. CONCLUSION: Increased expression of ICOS predicted poor outcomes, and ICOS/PD-1 was the optimal combination of ICs to predict outcomes in patients with AML, which might be a potential immune biomarker for designing novel AML therapy.

5.
ACS Nano ; 2024 Apr 14.
Artigo em Inglês | MEDLINE | ID: mdl-38616401

RESUMO

External electric field has the potential to influence metabolic processes such as biological hydrogen production in microorganisms. Based on this concept, we designed and constructed an electroactive hybrid system for microbial biohydrogen production under an electric field comprised of polydopamine (PDA)-modified Escherichia coli (E. coli) and Ni foam (NF). In this system, electrons generated from NF directly migrate into E. coli cells to promote highly efficient biocatalytic hydrogen production. Compared to that generated in the absence of electric field stimulation, biohydrogen production by the PDA-modified E. coli-based system is significantly enhanced. This investigation has demonstrated the mechanism for electron transfer in a biohybrid system and gives insight into precise basis for the enhancement of hydrogen production by using the multifield coupling technology.

6.
Sensors (Basel) ; 24(7)2024 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-38610296

RESUMO

The contact wire wear is an important parameter to ensure the safety operation of electric railways. The contact wire may break if the wear is serious, which leads to transportation interruptions. This study proposes an optical measurement method of contact wire wear, using stereovision technology. The matching method of stereovision based on line-scan cameras is proposed. A lookup-table method is developed to exactly determine the image resolution caused by the contact wire being in different spatial positions. The wear width of the contact wire is extracted from catenaries' images, and the residual thickness of the contact wire is calculated. The method was verified by field tests. The round-robin tests of the residual thickness at the same location present excellent measurement repetitiveness. The maximum difference value between dynamic test results and ground measurement results is 0.13 mm. This research represents a potential way to implement condition-based maintenance for contact wire wear in the future in order to improve the maintenance efficiency and ensure the safety of catenary infrastructure.

7.
Anal Chem ; 96(15): 5985-5991, 2024 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-38557031

RESUMO

Super-resolution fluorescence imaging is a crucial method for visualizing the dynamics of the cell membrane involved in various physiological and pathological processes. This requires bright fluorescent dyes with excellent photostability and labeling stability to enable long-term imaging. In this context, we introduce a buffering-strategy-based cyanine dye, SA-Cy5, designed to identify and label carbonic anhydrase IX (CA IX) located in the cell membrane. The unique feature of SA-Cy5 lies in its ability to overcome photobleaching. When the dye on the cell membrane undergoes photobleaching, it is rapidly replaced by an intact probe from the buffer pool outside the cell membrane. This dynamic replacement ensures that the fluorescence intensity on the cell membrane remains stable over time. Under the super-resolution structured illumination microscopy (SIM), the cell membrane can be continuously imaged for 60 min with a time resolution of 20 s. This extended imaging period allows for the observation of substructural dynamics of the cell membrane, including the growth and fusion of filamentous pseudopodia and the fusion of vesicles. Additionally, this buffering strategy introduces a novel approach to address the issue of poor photostability associated with the cyanine dyes.


Assuntos
Corantes Fluorescentes , Imagem Óptica , Carbocianinas/química , Corantes Fluorescentes/química , Membrana Celular
8.
J Am Chem Soc ; 146(15): 10806-10811, 2024 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-38572914

RESUMO

The development of efficient catalysts for the hydrogenation of CO2 to methanol using "green" H2 is foreseen to be a key step to close the carbon cycle. In this study, we show that small and narrowly distributed alloyed PtGa nanoparticles supported on silica, prepared via a surface organometallic chemistry (SOMC) approach, display notable activity for the hydrogenation of CO2 to methanol, reaching a 7.2 molCH3OH h-1 molPt-1 methanol formation rate with a 54% intrinsic CH3OH selectivity. This reactivity sharply contrasts with what is expected for Pt, which favors the reverse water gas shift reaction, albeit with poor activity (2.6 molCO2 h-1 molPt-1). In situ XAS studies indicate that ca. 50% of Ga is reduced to Ga0 yielding alloyed PtGa nanoparticles, while the remaining 50% persist as isolated GaIII sites. The PtGa catalyst slightly dealloys under CO2 hydrogenation conditions and displays redox dynamics with PtGa-GaOx interfaces responsible for promoting both the CO2 hydrogenation activity and methanol selectivity. Further tailoring the catalyst interface by using a carbon support in place of silica enables to improve the methanol formation rate by a factor of ∼5.

9.
Nat Commun ; 15(1): 2853, 2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38565883

RESUMO

Aberrant glycosylation is a crucial strategy employed by cancer cells to evade cellular immunity. However, it's unclear whether homologous recombination (HR) status-dependent glycosylation can be therapeutically explored. Here, we show that the inhibition of branched N-glycans sensitizes HR-proficient, but not HR-deficient, epithelial ovarian cancers (EOCs) to immune checkpoint blockade (ICB). In contrast to fucosylation whose inhibition sensitizes EOCs to anti-PD-L1 immunotherapy regardless of HR-status, we observe an enrichment of branched N-glycans on HR-proficient compared to HR-deficient EOCs. Mechanistically, BRCA1/2 transcriptionally promotes the expression of MGAT5, the enzyme responsible for catalyzing branched N-glycans. The branched N-glycans on HR-proficient tumors augment their resistance to anti-PD-L1 by enhancing its binding with PD-1 on CD8+ T cells. In orthotopic, syngeneic EOC models in female mice, inhibiting branched N-glycans using 2-Deoxy-D-glucose sensitizes HR-proficient, but not HR-deficient EOCs, to anti-PD-L1. These findings indicate branched N-glycans as promising therapeutic targets whose inhibition sensitizes HR-proficient EOCs to ICB by overcoming immune evasion.


Assuntos
Proteína BRCA1 , Neoplasias Ovarianas , Humanos , Feminino , Animais , Camundongos , Proteína BRCA1/metabolismo , Inibidores de Checkpoint Imunológico/uso terapêutico , Linfócitos T CD8-Positivos/metabolismo , Glicosilação , Proteína BRCA2/metabolismo , Neoplasias Ovarianas/patologia , Carcinoma Epitelial do Ovário/tratamento farmacológico , Antígeno B7-H1/metabolismo
10.
Am J Clin Nutr ; 119(4): 1027-1035, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38569774

RESUMO

BACKGROUND: The postoperative inflammatory response is associated with postoperative recovery in surgery. n-3 (ω-3) polyunsaturated fatty acids have been reported to lower inflammation. The postoperative role of parenteral n-3 polyunsaturated fatty acids supplementation on outcomes in Crohn's disease after bowel resection is unclear. OBJECTIVES: We aimed to investigate the effects of postoperative parenteral n-3 polyunsaturated fatty acids supplementation in Crohn's disease. METHODS: A prospective randomized, unblinded controlled clinical trial was conducted for patients with Crohn's disease who underwent bowel resection between May 2019 and February 2022. Postoperative complications, complete blood count, serum biochemical values, and cytokine concentrations were compared in patients with and without parenteral n-3 polyunsaturated fatty acids supplementation for 5 d postoperatively. RESULTS: There were 268 patients randomly assigned in the analysis, with 134 in the control group (a mix of long-chain and medium-chain fats at 1.0 g/kg/d) and 134 in the treatment group (long-chain, medium-chain, and n-3 polyunsaturated fats at 1.2 g/kg/d). Twenty-six did not complete the allocated treatment, and 8 patients were lost to follow-up. The intention-to-treat analysis and the per-protocol analysis showed that there were a significant reduction in overall complication rates (22.4% compared with 49.3%; P < 0.001 and 21.8% compared with 38.2%; P = 0.006) and postoperative stay (8.8 ± 4.5 d compared with 11.2 ± 6.8 d; P = 0.001 and 8.7 ± 4.0 d compared with 11.5 ± 7.3 d; P < 0.001) in patients with parenteral n-3 polyunsaturated fatty acids supplementation compared with patients in the control group. In the secondary outcomes, the mean ± standard deviation of interleukin (IL)-6 (17.11 ± 2.14 pg/mL compared with 30.50 ± 5.14 pg/mL; P = 0.014), IL-1ß (2.01 ± 0.05 pg/mL compared with 2.24 ± 0.09 pg/mL; P = 0.019), tumor necrosis factor-α (2.09 ± 0.06 pg/mL compared with 2.29 ± 0.06 pg/mL; P = 0.029), and C-reactive protein concentrations (51.3 ± 4.2 mg/L compared with 64.4 ± 5.3 mg/L; P = 0.050) on postoperative day 5 in the treatment group were much lower than those in the control group. CONCLUSIONS: Parenteral n-3 polyunsaturated fatty acids supplementation promotes postoperative recovery in patients with Crohn's disease following bowel resection, with fewer complications and reduced inflammatory cytokines. This trial was registered at clinicaltrials.gov as NCT03901937 at https://classic. CLINICALTRIALS: gov/ct2/show/NCT03901937?term=NCT03901937&cond=Crohn+Disease&draw=2&rank=1.


Assuntos
Doença de Crohn , Ácidos Graxos Ômega-3 , Humanos , Doença de Crohn/tratamento farmacológico , Doença de Crohn/cirurgia , Estudos Prospectivos , Ácidos Graxos Ômega-3/uso terapêutico , Nutrição Parenteral , Citocinas , Interleucina-6 , Suplementos Nutricionais
11.
Coron Artery Dis ; 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38563191

RESUMO

BACKGROUND: Left ventricular thrombus (LVT) is a severe cardiovascular complication occurring in approximately 10% of patients with acute anterior ST-segment elevation myocardial infarction. This study aimed to evaluate the association between neutrophil-to-lymphocyte ratio (NLR) and in-hospital major adverse cardiovascular and cerebrovascular events (MACCE) in patients with LVT. MATERIAL AND METHODS: This multicenter retrospective study was conducted between January 2000 and June 2022 in hospitalized patients with LVT. The outcome included in-hospital MACCE. The association between NLR and in-hospital MACCE was measured by odds ratios (ORs). The restricted cubic spline model was used for dose-response analysis. RESULTS: A total of 197 LVT patients from four centers were included for analysis in this study. MACCE occurred in 13.7% (27/197) of the patients. After adjusting for estimated glomerular filtration rate (eGFR), D-dimer, and age, the OR for MACCE comparing first to the third tertile of NLR was 13.93 [95% confidence interval: 2.37-81.77, P = 0.004, P-trend = 0.008]. When further adjusting for etiology and heart failure with reduced ejection fraction (HFrEF), the association remained statistically significant. Spline regression models showed an increasing trend in the incidence of MACCEs with NLR both in crude and adjusted models. Subgroup analyses showed that a high NLR may be correlated with poorer outcomes for LVT patients older than 65 years, or with hypertension, dyslipidemia, low ejection fraction, liver, and renal dysfunctions. CONCLUSION: In conclusion, these findings suggested that higher NLR may be associated with an increased risk of in-hospital MACCE in patients with LVT.

12.
Opt Express ; 32(6): 9602-9609, 2024 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-38571190

RESUMO

The thin flyer is a small-scale flying object, which is well known as the core functional element of the initiator. Understanding how flyers perform has been a long-standing issue in detonator science. However, it remains a significant challenge to explore how the flyer is formed and functions in the barrel of the initiator via tabletop devices. In this study, we present dynamic and unprecedented images of flyer in barrel via high intensity short-pulse laser. Advanced radiography, coupled with a high-intensity picosecond laser X-ray source, has enabled the provision of state-of-the-art radiographs in a single-shot experiment for observing micron-scale flyer formation in a hollow cylinder in nanoseconds. The flyer was clearly visible in the barrel and was accelerated and restricted differently from that without the barrel. This first implementation of a tabletop X-ray source provided a new approach for capturing dynamic photographs of small-scale flying objects, which were previously reported to be accessible only via an X-ray phase-contrast imaging system at the advanced photon source. These efforts have led to a significant improvement of radiographic capability and a greater understanding of the mechanisms of "burst" of exploding foil initiators for this application.

13.
Artigo em Inglês | MEDLINE | ID: mdl-38567413

RESUMO

Inflammatory bowel disease (IBD) is a debilitating condition that can lead to life-threatening complications. Macrophages are crucial in IBD management because they secrete various cytokines and regulate tissue repair. Macrophage-derived angiogenin (ANG) has been shown to be essential for limiting colonic inflammation, but its upstream regulatory pathway and role in macrophages remain unclear. Here we show that ANG expression is up-regulated in macrophages during colitis treatment or upon lipopolysaccharides (LPS) treatment. Mechanistically, LPS activates Toll-like receptor 4 (TLR4) to initiate NF-κB translocation from the cytoplasm to the nucleus, where it binds to the ANG promoter and enhances its transcriptional activity, leading to increased ANG expression. Interestingly, our data also reveal that the deletion of ANG in macrophages has no adverse effect on key macrophage functions, such as phagocytosis, chemotaxis, and cell survival. Our findings establish a "LPS-TLR4-NF-κB-ANG" regulatory axis in inflammatory disorders and confirm that ANG controls inflammation in a paracrine manner, highlighting the importance of ANG as a key mediator in the complex network of inflammatory processes.

14.
Soft Matter ; 2024 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-38567443

RESUMO

The self-organization of stem cells (SCs) constitutes the fundamental basis of the development of biological organs and structures. SC-driven patterns are essential for tissue engineering, yet unguided SCs tend to form chaotic patterns, impeding progress in biomedical engineering. Here, we show that simple geometric constraints can be used as an effective mechanical modulation approach that promotes the development of controlled self-organization and pattern formation of SCs. Using the applied SC guidance with geometric constraints, we experimentally uncover a remarkable deviation in cell aggregate orientation from a random direction to a specific orientation. Subsequently, we propose a dynamic mechanical framework, including cells, the extracellular matrix (ECM), and the culture environment, to characterize the specific orientation deflection of guided cell aggregates relative to initial geometric constraints, which agrees well with experimental observation. Based on this framework, we further devise various theoretical strategies to realize complex biological patterns, such as radial and concentric structures. Our study highlights the key role of mechanical factors and geometric constraints in governing SCs' self-organization. These findings yield critical insights into the regulation of SC-driven pattern formation and hold great promise for advancements in tissue engineering and bioactive material design for regenerative application.

15.
Science ; 384(6692): 189-193, 2024 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-38603485

RESUMO

Inverted (pin) perovskite solar cells (PSCs) afford improved operating stability in comparison to their nip counterparts but have lagged in power conversion efficiency (PCE). The energetic losses responsible for this PCE deficit in pin PSCs occur primarily at the interfaces between the perovskite and the charge-transport layers. Additive and surface treatments that use passivating ligands usually bind to a single active binding site: This dense packing of electrically resistive passivants perpendicular to the surface may limit the fill factor in pin PSCs. We identified ligands that bind two neighboring lead(II) ion (Pb2+) defect sites in a planar ligand orientation on the perovskite. We fabricated pin PSCs and report a certified quasi-steady state PCE of 26.15 and 24.74% for 0.05- and 1.04-square centimeter illuminated areas, respectively. The devices retain 95% of their initial PCE after 1200 hours of continuous 1 sun maximum power point operation at 65°C.

16.
Invest Radiol ; 2024 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-38595181

RESUMO

OBJECTIVES: The purpose of this study is to determine if a universal 120-kV ultra-high pitch and virtual monoenergetic images (VMIs) protocol on the photon-counting computed tomography (PCCT) system can provide sufficient image quality for pediatric abdominal imaging, regardless of size, compared with protocols using a size-dependent kV and dual-source flash mode on the energy-integrating CT (EICT) system. MATERIALS AND METHODS: One solid water insert and 3 iodine (2, 5, 10 mg I/mL) inserts were attached or inserted into phantoms of variable sizes, simulating the abdomens of a newborn, 5-year-old, 10-year-old, and adult-sized pediatric patients. Each phantom setting was scanned on an EICT using clinical size-specific kV dual-source protocols with a pitch of 3.0. The scans were performed with fixed scanning parameters, and the CTDIvol values of full dose were 0.30, 0.71, 1.05, and 7.40 mGy for newborn to adult size, respectively. In addition, half dose scans were acquired on EICT. Each phantom was then scanned on a PCCT (Siemens Alpha) using a universal 120-kV protocol with the same full dose and half dose as determined above on the EICT scanner. All other parameters matched to EICT settings. Virtual monoenergetic images were generated from PCCT scans between 40 and 80 keV with a 5-keV interval. Image quality metrics were compared between PCCT VMIs and EICT, including image noise (measured as standard deviation of solid water), contrast-to-noise ratio (CNR) (measured at iodine inserts with solid water as background), and noise power spectrum (measured in uniform phantom regions). RESULTS: Noise at a PCCT VMI of 70 keV (7.0 ± 0.6 HU for newborn, 14.7 ± 1.6 HU for adult) is comparable (P > 0.05, t test) or significantly lower (P < 0.05, t test) compared with EICT (7.8 ± 0.8 HU for newborn, 15.3 ± 1.5 HU for adult). Iodine CNR from PCCT VMI at 50 keV (50.8 ± 8.4 for newborn, 27.3 ± 2.8 for adult) is comparable (P > 0.05, t test) or significantly higher (P < 0.05, t test) to the corresponding EICT measurements (57.5 ± 6.7 for newborn, 13.8 ± 1.7 for adult). The noise power spectrum curve shape of PCCT VMI is similar to EICT, despite PCCT VMI exhibiting higher noise at low keV levels. CONCLUSIONS: The universal PCCT 120 kV with ultra-high pitch and postprocessed VMIs demonstrated equivalent or improved performance in noise (70 keV) and iodine CNR (50 keV) for pediatric abdominal CT, compared with size-specific kV images on the EICT.

17.
Natl Sci Rev ; 11(5): nwae055, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38577668

RESUMO

Enhancing the quality of junctions is crucial for optimizing carrier extraction and suppressing recombination in semiconductor devices. In recent years, metal halide perovskite has emerged as the most promising next-generation material for optoelectronic devices. However, the construction of high-quality perovskite junctions, as well as characterization and understanding of their carrier polarity and density, remains a challenge. In this study, using combined electrical and spectroscopic characterization techniques, we investigate the doping characteristics of perovskite films by remote molecules, which is corroborated by our theoretical simulations indicating Schottky defects consisting of double ions as effective charge dopants. Through a post-treatment process involving a combination of biammonium and monoammonium molecules, we create a surface layer of n-type low-dimensional perovskite. This surface layer forms a heterojunction with the underlying 3D perovskite film, resulting in a favorable doping profile that enhances carrier extraction. The fabricated device exhibits an outstanding open-circuit voltage (VOC) up to 1.34 V and achieves a certified efficiency of 19.31% for single-junction wide-bandgap (1.77 eV) perovskite solar cells, together with significantly enhanced operational stability, thanks to the improved separation of carriers. Furthermore, we demonstrate the potential of this wide-bandgap device by achieving a certified efficiency of 27.04% and a VOC of 2.12 V in a perovskite/perovskite tandem solar cell configuration.

18.
Commun Biol ; 7(1): 432, 2024 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-38594418

RESUMO

Trace elements are important for human health but may exert toxic or adverse effects. Mechanisms of uptake, distribution, metabolism, and excretion are partly under genetic control but have not yet been extensively mapped. Here we report a comprehensive multi-element genome-wide association study of 57 essential and non-essential trace elements. We perform genome-wide association meta-analyses of 14 trace elements in up to 6564 Scandinavian whole blood samples, and genome-wide association studies of 43 trace elements in up to 2819 samples measured only in the Trøndelag Health Study (HUNT). We identify 11 novel genetic loci associated with blood concentrations of arsenic, cadmium, manganese, selenium, and zinc in genome-wide association meta-analyses. In HUNT, several genome-wide significant loci are also indicated for other trace elements. Using two-sample Mendelian randomization, we find several indications of weak to moderate effects on health outcomes, the most precise being a weak harmful effect of increased zinc on prostate cancer. However, independent validation is needed. Our current understanding of trace element-associated genetic variants may help establish consequences of trace elements on human health.


Assuntos
Selênio , Oligoelementos , Masculino , Humanos , Oligoelementos/metabolismo , Estudo de Associação Genômica Ampla , Zinco , Selênio/análise , Manganês
19.
J Environ Manage ; 357: 120823, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38583380

RESUMO

Fe(II) regeneration plays a crucial role in the electro-Fenton process, significantly influencing the rate of ·OH formation. In this study, a method is proposed to improve Fe(II) regeneration through N-doping aimed at enhancing the adsorption capacity of the activated carbon cathode for Fe(III). N-doping not only enriched the pore structure on the surface of activated carbon, providing numerous adsorption sites, but also significantly increased the adsorption energy for Fe(III). Among the types of nitrogen introduced, pyridine-N exhibited the most substantial enhancement effect, followed by pyrrole-N, while graphite-N showed a certain degree of inhibition. Furthermore, N-doping facilitated the adsorption of all forms of Fe(III) by activated carbon. The adsorption and electrosorption rates of the NAC-900 electrode for Fe(III) were 30.33% and 42.36%, respectively. Such modification markedly enhanced the Fe3+/Fe2+ cycle within the electro-Fenton system. The NAC-900 system demonstrated an impressive phenol degradation efficiency of 93.67%, alongside the lowest electricity consumption attributed to the effective "adsorption-reduction" synergy for Fe(III) on the NAC-900 electrode. Compared to the AC cathode electro-Fenton system, the degradation efficiency of the NAC-900 cathode electro-Fenton system at pH = levels ranging from 3 to 5 exceeded 90%; thus, extending the pH applicability of the electro-Fenton process. The degradation efficiency of phenol using the NAC-900 cathode electro-Fenton system in various water matrices approached 90%, indicating robust performance in real wastewater treatment scenarios. This research elucidates the impact of cathodic Fe(III) adsorption on Fe(II) regeneration within the electro-Fenton system, and clarifies the influence of different N- doping types on the cathodic adsorption of Fe(III).


Assuntos
Compostos Férricos , Poluentes Químicos da Água , Adsorção , Poluentes Químicos da Água/química , Carvão Vegetal/química , Conservação de Recursos Energéticos , Oxirredução , Eletrodos , Fenol , Compostos Ferrosos , Peróxido de Hidrogênio/química
20.
Sci Total Environ ; 928: 172435, 2024 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-38615758

RESUMO

Knowledge regarding the occurrence of short-chain and medium-chain chlorinated paraffins (SCCPs and MCCPs) in foodstuffs and their dietary exposure risks for rural Tibetan residents remains largely unknown. Herein, we collected main foodstuffs (including highland barley, vegetables, Tibetan butter, mutton, and yak beef) across the rural Tibetan Plateau and characterized the CP profiles and concentrations. The highest SCCPs concentrations were detected in Tibetan butter (geometric mean (GM): 240.6 ng/g wet weight (ww)), followed by vegetables (59.4 ng/g ww), mutton (51.4 ng/g ww), highland barley (46.3 ng/g ww), and yak beef (31.7 ng/g ww). For MCCPs, the highest concentrations were also detected in Tibetan butter (319.5 ng/g ww), followed by mutton (181.9 ng/g ww), vegetables (127.0 ng/g ww), yak beef (71.2 ng/g ww), and highland barley (30.3 ng/g ww). The predominant congener profiles of SCCPs were C13Cl7-8 in mutton and yak beef, C10Cl7-8 in Tibetan butter, and C10-11Cl6-7 in highland barley and vegetables. The predominant congener profiles of MCCPs were C14Cl7-9 in all sample types. Combined with our previous results of free-range chicken eggs, the median estimated daily intakes (EDIs) of SCCPs and MCCPs via diet for Tibetan rural adults and children was estimated to be 728.8 and 1853.9 ng/kg bw/day and 2565.6 and 5952.8 ng/kg bw/day, respectively. In the worst scenario, MCCPs might induce potential health risks for rural Tibetan population. To our knowledge, this is the first systematic dietary exposure research of SCCPs and MCCPs in the remote rural areas.

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