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1.
J Am Chem Soc ; 2024 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-39031766

RESUMO

Lower olefins are widely used in the chemical industry as basic carbon-based feedstocks. Here, we report the catalytic system featuring isolated single-atom sites of iridium (Ir1) that can function within the entire temperature range of 300-600 °C and transform alkanes with conversions close to thermodynamics-dictated levels. The high turnover frequency values of the Ir1 system are comparable to those of homogeneous catalytic reactions. Experimental data and theoretical calculations both indicate that Ir1 is the primary catalytic site, while the coordinating C and N atoms help to enhance the activity and stability, respectively; all three kinds of elements cooperatively contribute to the high performance of this novel active site. We have further immobilized this catalyst on particulate Al2O3, and we found that the resulting composite system under mimicked industrial conditions could still give high catalytic performances; in addition, we have also developed and established a new scheme of periodical in situ regeneration specifically for this composite particulate catalyst.

3.
Sci Adv ; 10(30): eadn3053, 2024 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-39047091

RESUMO

Vestimentiferan tubeworms that thrive in deep-sea chemosynthetic ecosystems rely on a single species of sulfide-oxidizing gammaproteobacterial endosymbionts housed in a specialized symbiotic organ called trophosome as their primary carbon source. While this simple symbiosis is remarkably productive, the host-symbiont molecular interactions remain unelucidated. Here, we applied an approach for deep-sea in situ single-cell fixation in a cold-seep tubeworm, Paraescarpia echinospica. Single-cell RNA sequencing analysis and further molecular characterizations of both the trophosome and endosymbiont indicate that the tubeworm maintains two distinct metabolic "microniches" in the trophosome by controlling the availability of chemosynthetic gases and metabolites, resulting in oxygenated and hypoxic conditions. The endosymbionts in the oxygenated niche actively conduct autotrophic carbon fixation and are digested for nutrients, while those in the hypoxic niche conduct anaerobic denitrification, which helps the host remove ammonia waste. Our study provides insights into the molecular interactions between animals and their symbiotic microbes.


Assuntos
Poliquetos , RNA-Seq , Análise de Célula Única , Simbiose , Animais , Análise de Célula Única/métodos , Poliquetos/metabolismo , Poliquetos/microbiologia , Poliquetos/genética , RNA-Seq/métodos , Gammaproteobacteria/metabolismo , Gammaproteobacteria/genética , Análise da Expressão Gênica de Célula Única
4.
Sci Rep ; 14(1): 10540, 2024 05 08.
Artigo em Inglês | MEDLINE | ID: mdl-38719945

RESUMO

Viruses are crucial for regulating deep-sea microbial communities and biogeochemical cycles. However, their roles are still less characterized in deep-sea holobionts. Bathymodioline mussels are endemic species inhabiting cold seeps and harboring endosymbionts in gill epithelial cells for nutrition. This study unveiled a diverse array of viruses in the gill tissues of Gigantidas platifrons mussels and analyzed the viral metagenome and transcriptome from the gill tissues of Gigantidas platifrons mussels collected from a cold seep in the South Sea. The mussel gills contained various viruses including Baculoviridae, Rountreeviridae, Myoviridae and Siphovirdae, but the active viromes were Myoviridae, Siphoviridae, and Podoviridae belonging to the order Caudovirales. The overall viral community structure showed significant variation among environments with different methane concentrations. Transcriptome analysis indicated high expression of viral structural genes, integrase, and restriction endonuclease genes in a high methane concentration environment, suggesting frequent virus infection and replication. Furthermore, two viruses (GP-phage-contig14 and GP-phage-contig72) interacted with Gigantidas platifrons methanotrophic gill symbionts (bathymodiolin mussels host intracellular methanotrophic Gammaproteobacteria in their gills), showing high expression levels, and have huge different expression in different methane concentrations. Additionally, single-stranded DNA viruses may play a potential auxiliary role in the virus-host interaction using indirect bioinformatics methods. Moreover, the Cro and DNA methylase genes had phylogenetic similarity between the virus and Gigantidas platifrons methanotrophic gill symbionts. This study also explored a variety of viruses in the gill tissues of Gigantidas platifrons and revealed that bacteria interacted with the viruses during the symbiosis with Gigantidas platifrons. This study provides fundamental insights into the interplay of microorganisms within Gigantidas platifrons mussels in deep sea.


Assuntos
Bacteriófagos , Bivalves , Brânquias , Metagenômica , Animais , Metagenômica/métodos , Bacteriófagos/genética , Bacteriófagos/isolamento & purificação , Brânquias/microbiologia , Brânquias/virologia , Brânquias/metabolismo , Bivalves/microbiologia , Bivalves/virologia , Bivalves/genética , Perfilação da Expressão Gênica , Transcriptoma , Viroma/genética , Bactérias/genética , Bactérias/classificação , Simbiose/genética , Metagenoma
5.
Proc Natl Acad Sci U S A ; 121(21): e2318151121, 2024 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-38758696

RESUMO

Halide perovskites emerged as a revolutionary family of high-quality semiconductors for solar energy harvesting and energy-efficient lighting. There is mounting evidence that the exceptional optoelectronic properties of these materials could stem from unconventional electron-phonon couplings, and it has been suggested that the formation of polarons and self-trapped excitons could be key to understanding such properties. By performing first-principles simulations across the length scales, here we show that halide perovskites harbor a uniquely rich variety of polaronic species, including small polarons, large polarons, and charge density waves, and we explain a variety of experimental observations. We find that these emergent quasiparticles support topologically nontrivial phonon fields with quantized topological charge, making them nonmagnetic analog of the helical Bloch points found in magnetic skyrmion lattices.

6.
Sci Total Environ ; 933: 173184, 2024 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-38750754

RESUMO

Deep-sea toxicology is essential for deep-sea environmental impact assessment. Yet most toxicology experiments are conducted solely in laboratory settings, overlooking the complexities of the deep-sea environment. Here we carried out metal exposure experiments in both the laboratory and in situ, to compare and evaluate the response patterns of Gigantidas platifrons to metal exposure (copper [Cu] or cadmium [Cd] at 100 µg/L for 48 h). Metal concentrations, traditional biochemical parameters, and fatty acid composition were assessed in deep-sea mussel gills. The results revealed significant metal accumulation in deep-sea mussel gills in both laboratory and in situ experiments. Metal exposure could induce oxidative stress, neurotoxicity, an immune response, altered energy metabolism, and changes to fatty acid composition in mussel gills. Interestingly, the metal accumulating capability, biochemical response patterns, and fatty acid composition each varied under differing experimental systems. In the laboratory setting, Cd-exposed mussels exhibited a higher value for integrated biomarker response (IBR) while in situ the Cu-exposed mussels instead displayed a higher IBR value. This study emphasizes the importance of performing deep-sea toxicology experiments in situ and contributes valuable data to a standardized workflow for deep-sea toxicology assessment.


Assuntos
Bivalves , Cádmio , Mineração , Poluentes Químicos da Água , Animais , Poluentes Químicos da Água/toxicidade , Cádmio/toxicidade , Bivalves/efeitos dos fármacos , Bivalves/fisiologia , Brânquias/efeitos dos fármacos , Monitoramento Ambiental/métodos , Cobre/toxicidade , Biomarcadores/metabolismo
7.
J Hazard Mater ; 473: 134612, 2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-38761766

RESUMO

Metal pollution caused by deep-sea mining activities has potential detrimental effects on deep-sea ecosystems. However, our knowledge of how deep-sea organisms respond to this pollution is limited, given the challenges of remoteness and technology. To address this, we conducted a toxicity experiment by using deep-sea mussel Gigantidas platifrons as model animals and exposing them to different copper (Cu) concentrations (50 and 500 µg/L) for 7 days. Transcriptomics and LC-MS-based metabolomics methods were employed to characterize the profiles of transcription and metabolism in deep-sea mussels exposed to Cu. Transcriptomic results suggested that Cu toxicity significantly affected the immune response, apoptosis, and signaling processes in G. platifrons. Metabolomic results demonstrated that Cu exposure disrupted its carbohydrate metabolism, anaerobic metabolism and amino acid metabolism. By integrating both sets of results, transcriptomic and metabolomic, we find that Cu exposure significantly disrupts the metabolic pathway of protein digestion and absorption in G. platifrons. Furthermore, several key genes (e.g., heat shock protein 70 and baculoviral IAP repeat-containing protein 2/3) and metabolites (e.g., alanine and succinate) were identified as potential molecular biomarkers for deep-sea mussel's responses to Cu toxicity. This study contributes novel insight for assessing the potential effects of deep-sea mining activities on deep-sea organisms.


Assuntos
Biomarcadores , Cobre , Metabolômica , Transcriptoma , Poluentes Químicos da Água , Animais , Cobre/toxicidade , Poluentes Químicos da Água/toxicidade , Biomarcadores/metabolismo , Transcriptoma/efeitos dos fármacos , Mytilidae/genética , Mytilidae/efeitos dos fármacos , Mytilidae/metabolismo , Bivalves/efeitos dos fármacos , Bivalves/genética , Bivalves/metabolismo
8.
J Endocrinol ; 262(2)2024 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-38805496

RESUMO

Polycystic ovary syndrome (PCOS) is a condition resulting from the interaction between environmental factors and hereditary components, profoundly affecting offspring development. Although the etiology of this disease remains unclear, aberrant in utero androgen exposure is considered one of the pivotal pathogenic factors. Herein, we demonstrate the intergenerational inheritance of PCOS-like phenotypes in F2 female offspring through F1 males caused by maternal testosterone exposure in F0 mice. We found impaired serum hormone expression and reproductive system development in prenatal testosterone-treated F1 male and F2 female mice (PTF1 and PTF2). In addition, downregulated N6-methyladenosine (m6A) methyltransferase and binding proteins induced mRNA hypomethylation in the PTF1 testis, including frizzled-6 (Fzd6). In the PTF2 ovary, decreased FZD6 protein expression inhibited the mammalian target of rapamycin (mTOR) signaling pathway and activated Forkhead box O3 (FoxO3) phosphorylation, which led to impaired follicular development. These data indicate that epigenetic modification of the mTOR signaling pathway could be involved in the intergenerational inheritance of maternal testosterone exposure-induced impairments in the PTF2 ovary through male PTF1 mice.


Assuntos
Herança Paterna , Efeitos Tardios da Exposição Pré-Natal , Testosterona , Animais , Feminino , Masculino , Camundongos , Efeitos Tardios da Exposição Pré-Natal/genética , Gravidez , Testosterona/sangue , Herança Paterna/genética , Exposição Materna/efeitos adversos , Síndrome do Ovário Policístico/genética , Síndrome do Ovário Policístico/metabolismo , Síndrome do Ovário Policístico/induzido quimicamente , Epigênese Genética , Androgênios/farmacologia , Serina-Treonina Quinases TOR/metabolismo , Ovário/metabolismo , Ovário/efeitos dos fármacos , Testículo/metabolismo , Testículo/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/genética , Metilação de DNA/efeitos dos fármacos , Proteína Forkhead Box O3/metabolismo , Proteína Forkhead Box O3/genética
9.
Heliyon ; 10(5): e26452, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38449609

RESUMO

The research focuses on and analyses the effect of government investment on income distribution by evaluating the effects of public spending on income variation in various fields, in various regions, and at different income levels in the Chinese economy. The study found that government investment in different fields substantially decreases income inequality. Increasing housing security, medical, agriculture, forestry and other expenditures has a significant impact on improving the income inequality between rural and urban inhabitants; the impact of government investment in the western, central, and eastern regions on the reduction of income variation is decreasing successively, with emphasis on government investment in the western and central regions. The effects of government investment on the decline of the income distribution are twofold: first, it influences the amount of low- and middle-income groups; second, it has an impact on the reduction of high-income organizations; however, the impact on the income equality of high-income and low-income organizations is not considerable. In investment, the study demonstrates that income inequality can be reduced without negatively affecting the financial status of higher-income individuals. It is significant to value providing adequate housing security for low-income populations as a critical policy implication. This study, utilizing novel indicators, contributes to the current body of research on the impact of fiscal policy in addressing income inequality in China.

10.
Environ Sci Pollut Res Int ; 31(13): 19615-19634, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38363502

RESUMO

Green innovations are the most critical factor in promoting environmental sustainability worldwide. Trade can speed up the adoption of green innovations by facilitating the transfer of information, skills, and technology. However, trade policy uncertainty can create significant challenges for businesses investing in eco-innovations, leading to increased risk, reduced investment, and slower progress toward sustainable technologies. Recently, a growing number of researchers have shown their interest in finding the factors that can impact green innovations, but none have investigated the influence of trade policy uncertainty on green innovations in the USA and China. In addition, none of the past studies has relied on the nonlinear assumption. This analysis fills these gaps by examining the nonlinear impacts of trade policy uncertainty on eco-innovations in China and the USA over 2000Q1-2021Q4 by employing a nonlinear ARDL model. The finding reveals that a positive shock in trade policy uncertainty results in a decrease in green innovation in the USA and China, while a negative shock in trade policy uncertainty leads to an increase in green innovation in the USA over the long run. The nonlinear models also indicate that a positive shock in trade policy uncertainty harms green innovation in both the USA and China in the short run. The robustness of these results is confirmed by the NQARDL model, which confirms that an upsurge in trade policy uncertainty lowers green innovation in most quantiles in the USA and China in the short and long run. Conversely, negative shocks in trade policy uncertainty stimulate green innovation at most quantiles in both China and the USA, in the short and long run. Thus, policymakers need to consider the potential impact of trade policies on eco-innovations and work to create stable and predictable trade environments that support the growth of renewable technologies and other sustainable solutions.


Assuntos
Comércio , Investimentos em Saúde , Incerteza , China , Políticas , Desenvolvimento Econômico , Dióxido de Carbono , Energia Renovável
11.
Phys Rev Lett ; 132(3): 036902, 2024 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-38307080

RESUMO

Excitons consist of electrons and holes held together by their attractive Coulomb interaction. Although excitons are neutral excitations, spatial fluctuations in their charge density couple with the ions of the crystal lattice. This coupling can lower the exciton energy and lead to the formation of a localized excitonic polaron or even a self-trapped exciton in the presence of strong exciton-phonon interactions. Here, we develop a theoretical and computational approach to compute excitonic polarons and self-trapped excitons from first principles. Our methodology combines the many-body Bethe-Salpeter approach with density-functional perturbation theory and does not require explicit supercell calculations. As a proof of concept, we demonstrate our method for a compound of the halide perovskite family.

12.
Acta Psychol (Amst) ; 244: 104180, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38335811

RESUMO

A transition to a more sustainable society is occurring worldwide and necessitates a change in people's ways of consuming. Self-transcendence (ST) is recognized as a key predictor of green consumption. Thus, a multiple intermediary model was developed to clarify the psychological mechanisms underlying ST and its influence on consumption. The model was tested using data from a nationally representative sample of 428 Chinese participants. The results show that ST's overall positive effect on green consumption is realized via four indirect paths: (1) the simple mediating role of nature connectedness between ST and green consumption, (2) the simple mediating role of social connectedness between ST and green consumption; (3) the chain-mediating role of construction of meaning in life (CoMIL) and nature connectedness, and (4) the chain-mediating role of CoMIL and social connectedness. Among these paths, nature connectedness plays the most critical mediating role for the Chinese, accounting for the greatest proportion of the total indirect effect. The study advances understanding of the influence and path of ST on green consumption, and provides theoretical and practical support for guiding people toward sustainable lifestyles.


Assuntos
Povo Asiático , Humanos , Desenvolvimento Sustentável
13.
Front Microbiol ; 15: 1287147, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38380093

RESUMO

The sediment-water interfaces of cold seeps play important roles in nutrient transportation between seafloor and deep-water column. Microorganisms are the key actors of biogeochemical processes in this interface. However, the knowledge of the microbiome in this interface are limited. Here we studied the microbial diversity and potential metabolic functions by 16S rRNA gene amplicon sequencing at sediment-water interface of two active cold seeps in the northern slope of South China Sea, Lingshui and Site F cold seeps. The microbial diversity and potential functions in the two cold seeps are obviously different. The microbial diversity of Lingshui interface areas, is found to be relatively low. Microbes associated with methane consumption are enriched, possibly due to the large and continuous eruptions of methane fluids. Methane consumption is mainly mediated by aerobic oxidation and denitrifying anaerobic methane oxidation (DAMO). The microbial diversity in Site F is higher than Lingshui. Fluids from seepage of Site F are mitigated by methanotrophic bacteria at the cyclical oxic-hypoxic fluctuating interface where intense redox cycling of carbon, sulfur, and nitrogen compounds occurs. The primary modes of microbial methane consumption are aerobic methane oxidation, along with DAMO, sulfate-dependent anaerobic methane oxidation (SAMO). To sum up, anaerobic oxidation of methane (AOM) may be underestimated in cold seep interface microenvironments. Our findings highlight the significance of AOM and interdependence between microorganisms and their environments in the interface microenvironments, providing insights into the biogeochemical processes that govern these unique ecological systems.

14.
AIDS Res Ther ; 21(1): 8, 2024 01 31.
Artigo em Inglês | MEDLINE | ID: mdl-38297382

RESUMO

BACKGROUND: Studies on antiretroviral therapy (ART) in children living with HIV (CLHIV) are limited due to the small population and low accession rate of ART. METHODS: All 0-14-year-old CLHIV admitted to the Ganzhou Center for Disease Control and Prevention from January 2006 to June 2023 were included retrospectively. The information of treatment regimens, disease progression, and laboratory tests of the patients under ART were used to explore the outcomes and impacts of long-term ART. The normality of all the data was tested by the Shapiro-Wilk test. RESULTS: From 2006 to 2023, 18 CLHIV were reported in Ganzhou. Among them, 11 received ART and were followed up for 60.0 ± 48.4 months. After receiving ART, the median viral load of them decreased from 89,600 copies/ml to 22 copies/ml (P = 0.007), the median CD4+ T cell count increased from 380.7 cells/µL to 661.9 cells/µL (P = 0.028), and the median CD8+ T cell count decreased from 1065.8 cells/µL to 983.3 cells/µL (P = 0.584). The laboratory test results regarding liver function, renal function, blood cell count, and glucolipid metabolism tended to be within normal reference ranges, and the mean height-for-age z-score and weight-for-age z-score increased. However, all the three CLHIV who received cotrimoxazole developed pneumocystis carinii pneumonia, upper respiratory infection, skin lesions, bacterial pneumonia and/or thrush; the mean body-mass-index-for-age z-score decreased from 0.52 to -0.63. CONCLUSION: For CLHIV, ART could effectively inhibit the replication of HIV and improve the immune function of patients. More studies that focus on ART in CLHIV are urgently needed.


Assuntos
Fármacos Anti-HIV , Infecções por HIV , Criança , Humanos , Recém-Nascido , Lactente , Pré-Escolar , Adolescente , Infecções por HIV/epidemiologia , Estudos Retrospectivos , Antirretrovirais/uso terapêutico , Progressão da Doença , Contagem de Linfócito CD4 , China/epidemiologia , Carga Viral , Fármacos Anti-HIV/uso terapêutico
15.
Sci Rep ; 13(1): 21086, 2023 11 30.
Artigo em Inglês | MEDLINE | ID: mdl-38030755

RESUMO

Molecular-genetic imaging has greatly advanced clinical diagnosis and prognosis monitoring. However, the specific visualization of intracellular proteins such as estrogen receptor (ER) and progesterone receptor (PR) remains an elusive goal. Here, we highlight a novel method for selectively detecting ER/PR positive tumors using genetically engineered responsive elements. Our study demonstrates that the double responsive elements of ER/PR exhibit the most sensitivity to the steroid receptors in breast cancers. By utilizing a cationic polymer vector, we constructed a responsive element-fluorescence protein system that can selectively image ER/PR positive breast cancers in murine models under a near-infrared laser. This non-invasive imaging achieved high-resolution detection without death or serious anaphylactic activity in the animals. Our findings suggest that the reporter system consisting of steroid receptor response elements and near-infrared proteins provides a practical system for identifying biomarkers and advancing cancer diagnosis and therapy.


Assuntos
Neoplasias , Receptores de Progesterona , Animais , Camundongos , Receptores de Progesterona/genética , Receptores de Progesterona/metabolismo , Prognóstico , Imagem Óptica , Estrogênios
17.
Environ Sci Pollut Res Int ; 30(53): 113313-113322, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37848786

RESUMO

In order to reduce environmental deterioration and promote sustainable growth, green innovation-which includes ecologically friendly technology and practices-has become a top priority of policymakers worldwide. This research investigates how formal and informal finance affects green innovation in highly polluted high, middle-, and low-income economies, using data spanning from 2007 to 2021. For analyzing the empirical link between formal finance, informal finance, and green innovation, we have employed the 2SLS and GMM estimation techniques. The primary estimates of the analysis suggest that formal and informal funding methods significantly impact environment-related technologies in high-income and middle- and low-income nations. Moreover, the GDP, carbon emissions, trade openness, human capital, research and development, financial stability, and digital finance are essential factors in promoting environment-related technologies in high-, middle-, and low-income nations, respectively. The policymakers in both groups of countries should foster collaboration between the formal and informal sectors to promote green innovations, which is essential for achieving sustainable development goals.


Assuntos
Condições Sociais , Unionidae , Humanos , Animais , Carbono , Renda , Setor Informal , Desenvolvimento Econômico , Dióxido de Carbono , China
18.
Front Med (Lausanne) ; 10: 1159216, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37396910

RESUMO

Introduction: Interscalene block (ISB) is widely regarded as the gold standard treatment for acute pain following arthroscopic shoulder surgery. However, a single injection of a local anesthetic for ISB may not offer sufficient analgesia. Various adjuvants have been demonstrated to prolong the analgesic duration of the block. Hence, this study aimed to assess the relative efficacy of dexamethasone and dexmedetomidine as adjuncts to prolong the analgesic duration for a single- shot ISB. Methods: The efficacy of adjuvants was compared using a network meta-analysis. The methodological quality of the included studies was evaluated using the Cochrane bias risk assessment tool. A comprehensive search of the PubMed, Cochrane, Web of Science, and Embase databases was conducted with a search deadline of March 1, 2023. Various adjuvant prevention randomized controlled trials have been conducted in patients undergoing interscalene brachial plexus block for shoulder arthroscopic surgery. Results: Twenty-five studies enrolling a total of 2,194 patients reported duration of analgesia. Combined dexmedetomidine and dexamethasone (MD = 22.13, 95% CI 16.67, 27.58), dexamethasone administered perineurally (MD = 9.94, 95% CI 7.71, 12.17), high-dose intravenous dexamethasone (MD = 7.47, 95% CI 4.41, 10.53), dexmedetomidine administered perineurally (MD = 6.82, 95% CI 3.43, 10.20), and low-dose intravenous dexamethasone (MD = 6.72, 95% CI 3.74, 9.70) provided significantly longer analgesic effects compared with the control group. Discussion: The combination of intravenous dexamethasone and dexmedetomidine provided the greatest effect in terms of prolonged analgesia, reduced opioid doses, and lower pain scores. Furthermore, peripheral dexamethasone in prolonging the analgesic duration and lowering opioid usage was better than the other adjuvants when used a single medication. All therapies significantly prolonged the analgesic duration and reduced the opioid dose of a single-shot ISB in shoulder arthroscopy compared with the placebo.

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