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1.
Nature ; 613(7945): 676-681, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36379225

RESUMO

The open-circuit voltage (VOC) deficit in perovskite solar cells is greater in wide-bandgap (over 1.7 eV) cells than in perovskites of roughly 1.5 eV (refs. 1,2). Quasi-Fermi-level-splitting measurements show VOC-limiting recombination at the electron-transport-layer contact3-5. This, we find, stems from inhomogeneous surface potential and poor perovskite-electron transport layer energetic alignment. Common monoammonium surface treatments fail to address this; as an alternative, we introduce diammonium molecules to modify perovskite surface states and achieve a more uniform spatial distribution of surface potential. Using 1,3-propane diammonium, quasi-Fermi-level splitting increases by 90 meV, enabling 1.79 eV perovskite solar cells with a certified 1.33 V VOC and over 19% power conversion efficiency (PCE). Incorporating this layer into a monolithic all-perovskite tandem, we report a record VOC of 2.19 V (89% of the detailed balance VOC limit) and over 27% PCE (26.3% certified quasi-steady state). These tandems retained more than 86% of their initial PCE after 500 h of operation.

2.
Nature ; 618(7963): 74-79, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36977463

RESUMO

The tunable bandgaps and facile fabrication of perovskites make them attractive for multi-junction photovoltaics1,2. However, light-induced phase segregation limits their efficiency and stability3-5: this occurs in wide-bandgap (>1.65 electron volts) iodide/bromide mixed perovskite absorbers, and becomes even more acute in the top cells of triple-junction solar photovoltaics that require a fully 2.0-electron-volt bandgap absorber2,6. Here we report that lattice distortion in iodide/bromide mixed perovskites is correlated with the suppression of phase segregation, generating an increased ion-migration energy barrier arising from the decreased average interatomic distance between the A-site cation and iodide. Using an approximately 2.0-electron-volt rubidium/caesium mixed-cation inorganic perovskite with large lattice distortion in the top subcell, we fabricated all-perovskite triple-junction solar cells and achieved an efficiency of 24.3 per cent (23.3 per cent certified quasi-steady-state efficiency) with an open-circuit voltage of 3.21 volts. This is, to our knowledge, the first reported certified efficiency for perovskite-based triple-junction solar cells. The triple-junction devices retain 80 per cent of their initial efficiency following 420 hours of operation at the maximum power point.

3.
Genome Res ; 34(4): 633-641, 2024 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-38589250

RESUMO

Accurate detection of somatic mutations in DNA sequencing data is a fundamental prerequisite for cancer research. Previous analytical challenges were overcome by consensus mutation calling from four to five popular callers. This, however, increases the already nontrivial computing time from individual callers. Here, we launch MuSE 2, powered by multistep parallelization and efficient memory allocation, to resolve the computing time bottleneck. MuSE 2 speeds up 50 times more than MuSE 1 and eight to 80 times more than other popular callers. Our benchmark study suggests combining MuSE 2 and the recently accelerated Strelka2 achieves high efficiency and accuracy in analyzing large cancer genomic data sets.


Assuntos
Sequenciamento do Exoma , Mutação , Neoplasias , Sequenciamento Completo do Genoma , Humanos , Neoplasias/genética , Sequenciamento do Exoma/métodos , Sequenciamento Completo do Genoma/métodos , Software , Genoma Humano , Genômica/métodos , Algoritmos , Análise Mutacional de DNA/métodos
4.
Development ; 150(24)2023 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-38078650

RESUMO

Cochlear inner hair cells (IHCs) are primary sound receptors, and are therefore a target for developing treatments for hearing impairment. IHC regeneration in vivo has been widely attempted, although not yet in the IHC-damaged cochlea. Moreover, the extent to which new IHCs resemble wild-type IHCs remains unclear, as is the ability of new IHCs to improve hearing. Here, we have developed an in vivo mouse model wherein wild-type IHCs were pre-damaged and nonsensory supporting cells were transformed into IHCs by ectopically expressing Atoh1 transiently and Tbx2 permanently. Notably, the new IHCs expressed the functional marker vGlut3 and presented similar transcriptomic and electrophysiological properties to wild-type IHCs. Furthermore, the formation efficiency and maturity of new IHCs were higher than those previously reported, although marked hearing improvement was not achieved, at least partly due to defective mechanoelectrical transduction (MET) in new IHCs. Thus, we have successfully regenerated new IHCs resembling wild-type IHCs in many respects in the damaged cochlea. Our findings suggest that the defective MET is a critical barrier that prevents the restoration of hearing capacity and should thus facilitate future IHC regeneration studies.


Assuntos
Células Ciliadas Vestibulares , Perda Auditiva , Camundongos , Animais , Células Ciliadas Auditivas Internas , Cóclea/fisiologia , Perda Auditiva/genética , Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética
5.
Nat Mater ; 23(2): 182-188, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38182809

RESUMO

Multiferroic materials, particularly those possessing simultaneous electric and magnetic orders, offer a platform for design technologies and to study modern physics. Despite the substantial progress and evolution of multiferroics, one priority in the field remains to be the discovery of unexplored materials, especially those offering different mechanisms for controlling electric and magnetic orders1. Here we demonstrate the simultaneous thermal control of electric and magnetic polarizations in quasi-two-dimensional halides (K,Rb)3Mn2Cl7, arising from a polar-antipolar transition, as evidenced using both X-ray and neutron powder diffraction data. Our density functional theory calculations indicate a possible polarization-switching path including a strong coupling between the electric and magnetic orders in our halide materials, suggesting a magnetoelectric coupling and a situation not realized in oxide analogues. We expect our findings to stimulate the exploration of non-oxide multiferroics and magnetoelectrics to open access to alternative mechanisms, beyond conventional electric and magnetic control, for coupling ferroic orders.

6.
J Cell Mol Med ; 28(3): e18091, 2024 02.
Artigo em Inglês | MEDLINE | ID: mdl-38169083

RESUMO

Non-alcoholic fatty liver disease (NAFLD) is a major chronic liver disease worldwide. Cuproptosis has recently been reported as a form of cell death that appears to drive the progression of a variety of diseases. This study aimed to explore cuproptosis-related molecular clusters and construct a prediction model. The gene expression profiles were obtained from the Gene Expression Omnibus (GEO) database. The associations between molecular clusters of cuproptosis-related genes and immune cell infiltration were investigated using 50 NAFLD samples. Furthermore, cluster-specific differentially expressed genes were identified by the WGCNA algorithm. External datasets were used to verify and screen feature genes, and nomograms, calibration curves and decision curve analysis (DCA) were performed to verify the performance of the prediction model. Finally, a NAFLD-diet mouse model was constructed to further verify the predictive analysis, thus providing new insights into the prediction of NAFLD clusters and risks. The role of cuproptosis in the development of non-alcoholic fatty liver disease and immune cell infiltration was explored. Non-alcoholic fatty liver disease was divided into two cuproptosis-related molecular clusters by unsupervised clustering. Three characteristic genes (ENO3, SLC16A1 and LEPR) were selected by machine learning and external data set validation. In addition, the accuracy of the nomogram, calibration curve and decision curve analysis in predicting NAFLD clusters was also verified. Further animal and cell experiments confirmed the difference in their expression in the NAFLD mouse model and Mouse hepatocyte cell line. The present study explored the relationship between non-alcoholic fatty liver disease and cuproptosis, providing new ideas and targets for individual treatment of the disease.


Assuntos
Hepatopatia Gordurosa não Alcoólica , Animais , Camundongos , Algoritmos , Calibragem , Morte Celular , Linhagem Celular , Modelos Animais de Doenças , Apoptose
7.
Glia ; 72(3): 504-528, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37904673

RESUMO

Retinal degeneration, characterized by Müller cell gliosis and photoreceptor apoptosis, is considered an early event in diabetic retinopathy (DR). Our previous study proposed that GMFB may mediate diabetic retinal degeneration. This study identified GMFB as a sensitive and functional gliosis marker for DR. Compared to the wild type (WT) group, Gmfb knockout (KO) significantly improved visual function, attenuated gliosis, reduced the apoptosis of neurons, and decreased the mRNA levels of tumor necrosis factor α (Tnf-α) and interleukin-1ß (Il-1ß) in diabetic retinas. Tgf-ß3 was enriched by hub genes using RNA sequencing in primary WT and KO Müller cells. Gmfb KO significantly upregulated the transforming growth factor (TGF)-ß3 protein level via the AKT pathway. The protective effect of TGF-ß3 in the vitreous resulted in significantly improved visual function and decreased the number of apoptotic cells in the diabetic retina. The protection of Gmfb KO in primary Müller cells against high glucose (HG)-induced photoreceptor apoptosis was partially counteracted by TGF-ß3 antibody and administration of TGFBR1/2 inhibitors. Nuclear receptor subfamily 3 group C member 1 (NR3C1) binds to the promoter region of Gmfb and regulates Gmfb mRNA at the transcriptional level. NR3C1 was increased in the retinas of early diabetic rats but decreased in the retinas of late diabetic rats. N'-[(1E)-(3-Methoxyphenyl)Methylene]-3-Methyl-1H-Pyrazole-5-Carbohydrazide (DS-5) was identified as an inhibitor of GMFB, having a protective role in DR. We demonstrated that GMFB/AKT/TGF-ß3 mediated early diabetic retinal degeneration in diabetic rats. This study provides a novel therapeutic strategy for treating retinal degeneration in patients with DR.


Assuntos
Diabetes Mellitus Experimental , Retinopatia Diabética , Degeneração Retiniana , Humanos , Ratos , Animais , Degeneração Retiniana/patologia , Células Ependimogliais/metabolismo , Estreptozocina/toxicidade , Proteínas Proto-Oncogênicas c-akt/metabolismo , Fator de Crescimento Transformador beta3/efeitos adversos , Fator de Crescimento Transformador beta3/metabolismo , Diabetes Mellitus Experimental/induzido quimicamente , Diabetes Mellitus Experimental/metabolismo , Diabetes Mellitus Experimental/patologia , Gliose/patologia , Retina/metabolismo , Retinopatia Diabética/patologia , RNA Mensageiro/metabolismo
8.
EMBO J ; 39(24): e105896, 2020 12 15.
Artigo em Inglês | MEDLINE | ID: mdl-33140861

RESUMO

COVID-19 is characterized by dysregulated immune responses, metabolic dysfunction and adverse effects on the function of multiple organs. To understand host responses to COVID-19 pathophysiology, we combined transcriptomics, proteomics, and metabolomics to identify molecular markers in peripheral blood and plasma samples of 66 COVID-19-infected patients experiencing a range of disease severities and 17 healthy controls. A large number of expressed genes, proteins, metabolites, and extracellular RNAs (exRNAs) exhibit strong associations with various clinical parameters. Multiple sets of tissue-specific proteins and exRNAs varied significantly in both mild and severe patients suggesting a potential impact on tissue function. Chronic activation of neutrophils, IFN-I signaling, and a high level of inflammatory cytokines were observed in patients with severe disease progression. In contrast, COVID-19-infected patients experiencing milder disease symptoms showed robust T-cell responses. Finally, we identified genes, proteins, and exRNAs as potential biomarkers that might assist in predicting the prognosis of SARS-CoV-2 infection. These data refine our understanding of the pathophysiology and clinical progress of COVID-19.


Assuntos
COVID-19/sangue , COVID-19/patologia , Biomarcadores/sangue , COVID-19/imunologia , COVID-19/virologia , Feminino , Genômica/métodos , Humanos , Lipoproteínas/metabolismo , Masculino , Metabolômica/métodos , SARS-CoV-2/fisiologia , Índice de Gravidade de Doença , Carga Viral
9.
Small ; 20(28): e2400017, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38342597

RESUMO

The electron-phonon (e-ph) interactions are pivotal in shaping the electrical and thermal properties, and in particular, determining the carrier dynamics and transport behaviors in optoelectronic devices. By employing pump-probe spectroscopy and ultrafast microscopy, the consequential role of e-ph coupling strength in the spatiotemporal evolution of hot electrons is elucidated. Thermal transport across the metallic interface is controlled to regulate effective e-ph coupling factor Geff in Au and Au/Cr heterostructure, and their impact on nonequilibrium transport of hot electrons is examined. Via the modulation of buried Cr thickness, a strong correlation between Geff and the diffusive behavior of hot electrons is found. By enhancing Geff through the regulation of thermal transport across interface, there is a significant reduction in e-ph thermalization time, the maximum diffusion length of hot electrons, and lattice heated area which are extracted from the spatiotemporal evolution profiles. Therefore, the increased Geff significantly weakens the diffusion of hot electrons and promotes heat relaxation of electron subsystems in both time and space. These insights propose a robust framework for spatiotemporal investigations of G impact on hot electron diffusion, underscoring its significance in the rational design of advanced optoelectronic devices with high efficiency.

10.
Small ; : e2402371, 2024 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-38597692

RESUMO

Quantum dot (QD) light-emitting diodes (QLEDs) are promising for next-generation displays, but suffer from carrier imbalance arising from lower hole injection compared to electron injection. A defect engineering strategy is reported to tackle transport limitations in nickel oxide-based inorganic hole-injection layers (HILs) and find that hole injection is able to enhance in high-performance InP QLEDs using the newly designed material. Through optoelectronic simulations, how the electronic properties of NiOx affect hole injection efficiency into an InP QD layer, finding that efficient hole injection depends on lowering the hole injection barrier and enhancing the acceptor density of NiOx is explored. Li doping and oxygen enriching are identified as effective strategies to control intrinsic and extrinsic defects in NiOx, thereby increasing acceptor density, as evidenced by density functional theory calculations and experimental validation. With fine-tuned inorganic HIL, InP QLEDs exhibit a luminance of 45 200 cd m-2 and an external quantum efficiency of 19.9%, surpassing previous inorganic HIL-based QLEDs. This study provides a path to designing inorganic materials for more efficient and sustainable lighting and display technologies.

11.
Cardiovasc Diabetol ; 23(1): 273, 2024 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-39049086

RESUMO

BACKGROUND: Extracellular matrix (ECM) stiffness is closely related to the progress of diabetic cardiomyopathy (DCM) and the response of treatment of DCM to anti-diabetic drugs. Dapagliflozin (Dapa) has been proven to have cardio-protective efficacy for diabetes and listed as the first-line drug to treat heart failure. But the regulatory relationship between ECM stiffness and treatment efficacy of Dapa remains elusive. MATERIALS AND METHODS: This work investigated the effect of ECM stiffness on DCM progression and Dapa efficacy using both in vivo DCM rat model and in vitro myocardial cell model with high glucose injury. First, through DCM rat models with various levels of myocardial injury and administration with Dapa treatment for four weeks, the levels of myocardial injury, myocardial oxidative stress, expressions of AT1R (a mechanical signal protein) and the stiffness of myocardial tissues were obtained. Then for mimicking the stiffness of myocardial tissues at early and late stages of DCM, we constructed cell models through culturing H9c2 myocardial cells on the polyacrylamide gels with two stiffness and exposed to a high glucose level and without/with Dapa intervention. The cell viability, reactive oxygen species (ROS) levels and expressions of mechanical signal sensitive proteins were obtained. RESULTS: The DCM progression is accompanied by the increased myocardial tissue stiffness, which can synergistically exacerbate myocardial cell injury with high glucose. Dapa can improve the ECM stiffness-induced DCM progression and its efficacy on DCM is more pronounced on the soft ECM, which is related to the regulation pathway of AT1R-FAK-NOX2. Besides, Dapa can inhibit the expression of the ECM-induced integrin ß1, but without significant impact on piezo 1. CONCLUSIONS: Our study found the regulation and effect of biomechanics in the DCM progression and on the Dapa efficacy on DCM, providing the new insights for the DCM treatment. Additionally, our work showed the better clinical prognosis of DCM under early Dapa intervention.


Assuntos
Compostos Benzidrílicos , Cardiomiopatias Diabéticas , Matriz Extracelular , Glucosídeos , Miócitos Cardíacos , Estresse Oxidativo , Ratos Sprague-Dawley , Inibidores do Transportador 2 de Sódio-Glicose , Animais , Cardiomiopatias Diabéticas/fisiopatologia , Cardiomiopatias Diabéticas/metabolismo , Cardiomiopatias Diabéticas/tratamento farmacológico , Cardiomiopatias Diabéticas/etiologia , Cardiomiopatias Diabéticas/patologia , Glucosídeos/farmacologia , Matriz Extracelular/metabolismo , Matriz Extracelular/efeitos dos fármacos , Matriz Extracelular/patologia , Compostos Benzidrílicos/farmacologia , Miócitos Cardíacos/efeitos dos fármacos , Miócitos Cardíacos/patologia , Miócitos Cardíacos/metabolismo , Inibidores do Transportador 2 de Sódio-Glicose/farmacologia , Inibidores do Transportador 2 de Sódio-Glicose/uso terapêutico , Masculino , Estresse Oxidativo/efeitos dos fármacos , Linhagem Celular , Modelos Animais de Doenças , Espécies Reativas de Oxigênio/metabolismo , Ratos , Quinase 1 de Adesão Focal/metabolismo , Diabetes Mellitus Experimental/tratamento farmacológico , Diabetes Mellitus Experimental/metabolismo , Diabetes Mellitus Experimental/complicações
12.
J Exp Bot ; 75(1): 137-151, 2024 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-37738583

RESUMO

Carbon reserve remobilization in stems is closely related to rice grain filling. Sucrose phosphate synthase (SPS) is highly associated with carbon reserve remobilization. In this study, we investigated the expression pattern of SPS genes in various rice tissues, and found that SPS8 is the major SPS isoform in rice stems during the grain-filling stage. We then constructed sps8 mutants using the CRISPR/Cas9 system. The SPS activity of the sps8 mutants was markedly reduced in the stems. In addition, the sps8 mutants exhibited significant starch accumulation in stems. 14C-labelling experiments revealed that the remobilization of non-structural carbohydrates from rice stems to grains was impaired in the sps8 mutants. In the sps8 mutants, grain filling was delayed and yield decreased by 15% due to a reduced percentage of ripened grains. RNA sequencing and quantitative PCR analyses indicated that the genes involved in starch synthesis and degradation were up-regulated in the sps8 mutant stems. In addition, the activity of the enzymes involved in starch synthesis and degradation was increased in the sps8 stems. These results demonstrate that SPS8 is required for carbon reserve remobilization from rice stems to grains, and that its absence may enhance 'futile cycles' of starch synthesis and degradation in rice stems.


Assuntos
Carbono , Oryza , Carbono/metabolismo , Oryza/metabolismo , Grão Comestível/genética , Grão Comestível/metabolismo , Amido/metabolismo , Sacarose/metabolismo
13.
Allergy ; 79(2): 456-470, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38010254

RESUMO

BACKGROUND: New treatment options with improved safety and novel mechanisms of actions are needed for patients with peanut allergy. OBJECTIVES: To evaluate the safety, tolerability, and immunogenicity of ASP0892, a peanut DNA vaccine, after intradermal (id) or intramuscular (im) administration in adult or adolescent patients with peanut allergy in two phase 1 studies. METHODS: ASP0892 or placebo was administered every 2 weeks for a total of 4 doses. The doses were 1 mg or 4 mg id or 4 mg im for adults, and 1 mg or 4 mg id for adolescents. Immunologic parameters were assessed longitudinally. RESULTS: Thirty-one adults (mean age 24.3 years, 17 males) received ASP0892 (9, 8, 8 patients for 1 mg id, 4 mg id or 4 mg im, respectively) or placebo (2 patients/group). Twenty adolescents (mean age 14.2 years, 11 males) received ASP0892 (8 patients/group) or placebo (2 patients/group). In both studies, the most common treatment-emergent adverse event (TEAE) was injection site pruritus. No deaths or treatment withdrawal were related to TEAEs. No serious TEAEs related to treatment were observed in adult or adolescent patients. ASP0892 treatment led to modest increases in allergen-specific IgG and/or IgG4 in adults (1 mg id, 4 mg im) and adolescents (1 mg id, 4 mg id). No improvements in clinical outcomes, including double-blind placebo-controlled food challenge, were found after ASP0892 treatment. CONCLUSIONS: In two phase 1 studies, ASP0892 was well tolerated with modest but not clinically relevant changes in immune responses. GOV IDENTIFIERS: NCT02851277, NCT03755713.


Assuntos
Hipersensibilidade a Amendoim , Adolescente , Adulto , Humanos , Masculino , Adulto Jovem , Arachis , Dessensibilização Imunológica/efeitos adversos , Método Duplo-Cego , Hipersensibilidade a Amendoim/diagnóstico , Hipersensibilidade a Amendoim/tratamento farmacológico , Ensaios Clínicos Controlados Aleatórios como Assunto
14.
Biomacromolecules ; 25(8): 4956-4964, 2024 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-38985329

RESUMO

Platelet-derived extracellular vesicles (PEVs) showing great potential in wound healing have attracted increasing attention recently. Nondestructive isolation and effective utilization strategies are highly conducive for PEVs developing into recognized therapeutic entities. Here, we present an efficient strategy for PEV isolation and bacterial infected wound healing based on self-assembled DNA microflowers. First, DNA microflowers are prepared using rolling circle amplification. Then, the hydrophobic interaction between cholesteryl modified on DNA microflowers and the phospholipid bilayer membrane of PEVs leads to the formation of a network structure with improved mechanical strength and the separation of PEVs from biological samples. Finally, controlled release of PEVs is achieved through bacterial-induced hydrogel degradation. In vitro experiments demonstrate the obtained DNA hydrogel with good cytocompatibility and therapeutic potential. Taken together, the DNA microflower-based hydrogels with bioadhesive, self-healing, tunable mechanical properties and bacteria-responsive behavior offer substantial potential for EV isolation and wound healing.


Assuntos
Plaquetas , DNA , Vesículas Extracelulares , Hidrogéis , Cicatrização , Vesículas Extracelulares/química , Cicatrização/efeitos dos fármacos , DNA/química , Plaquetas/metabolismo , Humanos , Hidrogéis/química , Hidrogéis/farmacologia , Animais , Camundongos
15.
J Org Chem ; 89(5): 3271-3278, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38332626

RESUMO

Benzofuran-fused derivatives display important and reliable therapeutic properties. Herein, we describe the synthesis of benzofuran-fused oxepines using aurones and crotonate-derived sulfonium salts via a [4 + 3] annulation reaction in the presence of Cs2CO3. This reaction proceeds under mild and operationally simple conditions. The synthetic utility of this approach was highlighted by several transformations, including the efficient synthesis of a novel tetracyclic fused benzofuran derivative.

16.
Inorg Chem ; 63(22): 10207-10220, 2024 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-38767574

RESUMO

We prepared polyoxomolybdates with methylammonium countercations from methylammonium monomolybdate, (CH3NH3)2[MoO4], through two dehydrative condensation methods, acidifying in the aqueous solution and solid-state heating. Discrete (CH3NH3)10[Mo36O112(OH)2(H2O)14], polymeric ((CH3NH3)8[Mo36O112(H2O)14])n, and polymeric ((CH3NH3)4[γ-Mo8O26])n were selectively isolated via pH control of the aqueous (CH3NH3)2[MoO4] solution. The H2SO4-acidified solution of pH < 1 produced "sulfonated α-MoO3", polymeric ((CH3NH3)2[(MoO3)3(SO4)])n. The solid-state heating of (CH3NH3)2[MoO4] in air released methylamine and water to produce several methylammonium polyoxomolybdates in the sequence of discrete (CH3NH3)8[Mo7O24-MoO4], discrete (CH3NH3)6[Mo7O24], discrete (CH3NH3)8[Mo10O34], and polymeric ((CH3NH3)4[γ-Mo8O26])n, before their transformation into molybdenum oxides such as hexagonal-MoO3 and α-MoO3. Notably, some of their polyoxomolybdate structures were different from polyoxomolybdates produced from ammonium molybdates, such as (NH4)2[MoO4] or (NH4)6[Mo7O24], indicating that countercation affected the polyoxomolybdate structure. Moreover, among the tested polyoxomolybdates, (CH3NH3)6[Mo7O24] was the best negative staining reagent for the observation of the SARS-CoV-2 virus using transmission electron microscopy.

17.
Environ Sci Technol ; 58(29): 12954-12965, 2024 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-38995993

RESUMO

Addressing environmental factors has recently been recommended to curb the growing trend of anemia in low- and middle-income countries (LMICs). Fine particulate matter (PM2.5) generated by dust storms were concentrated in place with a high prevalence of anemia. In a multicounty, multicenter study, we analyzed the association between anemia and life-course averaged exposure to dust PM2.5 among children aged <5 years based on 0.65 million records from 47 LMICs. In the fully adjusted mixed effects model, each 10 µg/m3 increase in life-course averaged exposure to dust PM2.5 was associated with a 9.3% increase in the odds of anemia. The estimated exposure-response association was nonlinear, with a greater effect of dust PM2.5 exposure seen at low concentrations. Applying this association, we found that, in 2017, among all children aged <5 years in the 125 LMICs, dust PM2.5 contributed to 37.98 million cases of anemia. Results indicated that dust PM2.5 contributed a heavier burden than all of the well-identified risk factors did, except for iron deficiency. Our study revealed that long-term exposure to dust PM2.5 can be a novel risk factor, pronouncedly contributed to the burden of child anemia in LMICs, affected by land degradations or arid climate.


Assuntos
Anemia , Poeira , Material Particulado , Humanos , Anemia/epidemiologia , Pré-Escolar , Feminino , Masculino , Países em Desenvolvimento , Exposição Ambiental , Lactente , Fatores de Risco
18.
J Phys Chem A ; 128(2): 431-438, 2024 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-38190616

RESUMO

Octupolar molecules possessing a strong two-photon response are vital for numerous advanced applications. However, accurately predicting their two-photon absorption (TPA) spectra requires high-precision quantum chemical calculations, which are computationally expensive due to repeated simulations of molecular excited-state properties. To address this challenge, we introduce a deep learning approach capable of rapidly and accurately forecasting TPA spectra for octupolar molecules. By leveraging the geometric structure as an initial descriptor, we employ a graph neural network to predict the maximum two-photon transition wavelength and cross-section. Our model demonstrates a mean absolute percentage error of less than 4% compared to time-dependent density-functional theory calculations, effectively reproducing experimental observations. Notably, this deep learning technique is nearly 100 000 times faster than comparable quantum calculations, making it an efficient and cost-effective tool for simulating TPA properties of octupolar molecules. Furthermore, this method holds great promise for the high-throughput screening of exceptional TPA materials.

20.
Environ Res ; 245: 118039, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38147919

RESUMO

RATIONALE: Air pollution and extreme temperature and humidity are risk factors for lung dysfunction, but their interactions are not clearly understood. OBJECTIVES: To assess the impact of exposure to air pollutants and meteorological factors on lung function, and the contribution of their interaction to the overall effect. METHODS: The peak expiratory flow rates of 135 participants were repeatedly measured during up to four visits. Two weeks before each visit, the concentrations of gaseous pollutants and 19 fine particle components, and the temperature and relative humidity, were continuously monitored in the community where they lived. A Bayesian Kernel machine regression model was used to explore the non-linear exposure-response relationships of the peak expiratory flow rate with pollutant exposure and meteorological factors, and their interactions. MEASUREMENTS AND MAIN RESULTS: Increased temperature and relative humidity could exacerbate pollutant-associated decline in the peak expiratory flow rate, although their associations with lung dysfunction disappeared after adjustment for pollutant exposure. For example, declines of peak expiratory flow rate associated with interquartile range increase of 3-day cadmium exposure were -0.03 and -0.07 units, when temperature was at 0.1 and 19.5 °C, respectively. Decreased temperature were associated with declines of peak expiratory flow rate after adjustment for pollutant exposure, and had interaction with pollutant exposure on lung dysfunction. CONCLUSIONS: High temperature, low temperature, and high humidity were all high-risk factors for lung dysfunction, and their interactions with pollutant levels contributed greatly to the overall effects.


Assuntos
Poluentes Atmosféricos , Poluição do Ar , Poluentes Ambientais , Humanos , Idoso , Umidade , Temperatura , Teorema de Bayes , Material Particulado/toxicidade , Material Particulado/análise , Exposição Ambiental/efeitos adversos , Exposição Ambiental/análise , Poluição do Ar/análise , Poluentes Atmosféricos/toxicidade , Poluentes Atmosféricos/análise , Pulmão/química
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