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1.
Aging Med (Milton) ; 7(3): 414-423, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38975316

RESUMEN

Arterial stiffening is a critical risk factor contributing to the exponential rise in age-associated cardiovascular disease incidence. This process involves age-induced arterial proinflammation, collagen deposition, and calcification, which collectively contribute to arterial stiffening. The primary driver of proinflammatory processes leading to collagen deposition in the arterial wall is the transforming growth factor-beta1 (TGF-ß1) signaling. Activation of this signaling is pivotal in driving vascular extracellular remodeling, eventually leading to arterial fibrosis and calcification. Interestingly, the glycosylated protein vasorin (VASN) physically interacts with TGF-ß1, and functionally restraining its proinflammatory fibrotic signaling in arterial walls and vascular smooth muscle cells (VSMCs). Notably, as age advances, matrix metalloproteinase type II (MMP-2) is activated, which effectively cleaves VASN protein in both arterial walls and VSMCs. This age-associated/MMP-2-mediated decrease in VASN levels exacerbates TGF-ß1 activation, amplifying arterial fibrosis and calcification in the arterial wall. Importantly, TGF-ß1 is a downstream molecule of the angiotensin II (Ang II) signaling pathway in the arterial wall and VSMCs, which is modulated by VASN. Indeed, chronic administration of Ang II to young rats significantly activates MMP-2 and diminishes the VASN expression to levels comparable to untreated older control rats. This review highlights and discusses the role played by VASN in mitigating fibrosis and calcification by alleviating TGF-ß1 activation and signaling in arterial walls and VSMCs. Understanding these molecular physical and functional interactions may pave the way for establishing VASN-based therapeutic strategies to counteract adverse age-associated cardiovascular remodeling, eventually reducing the risk of cardiovascular diseases.

2.
Environ Sci Atmos ; 4(7): 740-753, 2024 Jul 11.
Artículo en Inglés | MEDLINE | ID: mdl-39006766

RESUMEN

Isoprene affects new particle formation rates in environments and experiments also containing monoterpenes. For the most part, isoprene reduces particle formation rates, but the reason is debated. It is proposed that due to its fast reaction with OH, isoprene may compete with larger monoterpenes for oxidants. However, by forming a large amount of peroxy-radicals (RO2), isoprene may also interfere with the formation of the nucleating species compared to a purely monoterpene system. We explore the RO2 cross reactions between monoterpene and isoprene oxidation products using the radical Volatility Basis Set (radical-VBS), a simplified reaction mechanism, comparing with observations from the CLOUD experiment at CERN. We find that isoprene interferes with covalently bound C20 dimers formed in the pure monoterpene system and consequently reduces the yields of the lowest volatility (Ultra Low Volatility Organic Carbon, ULVOC) VBS products. This in turn reduces nucleation rates, while having less of an effect on subsequent growth rates.

3.
PLoS Comput Biol ; 20(6): e1012165, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38875286

RESUMEN

Although adaptive cancer therapy shows promise in integrating evolutionary dynamics into treatment scheduling, the stochastic nature of cancer evolution has seldom been taken into account. Various sources of random perturbations can impact the evolution of heterogeneous tumors, making performance metrics of any treatment policy random as well. In this paper, we propose an efficient method for selecting optimal adaptive treatment policies under randomly evolving tumor dynamics. The goal is to improve the cumulative "cost" of treatment, a combination of the total amount of drugs used and the total treatment time. As this cost also becomes random in any stochastic setting, we maximize the probability of reaching the treatment goals (tumor stabilization or eradication) without exceeding a pre-specified cost threshold (or a "budget"). We use a novel Stochastic Optimal Control formulation and Dynamic Programming to find such "threshold-aware" optimal treatment policies. Our approach enables an efficient algorithm to compute these policies for a range of threshold values simultaneously. Compared to treatment plans shown to be optimal in a deterministic setting, the new "threshold-aware" policies significantly improve the chances of the therapy succeeding under the budget, which is correlated with a lower general drug usage. We illustrate this method using two specific examples, but our approach is far more general and provides a new tool for optimizing adaptive therapies based on a broad range of stochastic cancer models.


Asunto(s)
Algoritmos , Biología Computacional , Neoplasias , Procesos Estocásticos , Humanos , Neoplasias/terapia , Biología Computacional/métodos , Modelos Biológicos , Antineoplásicos/uso terapéutico , Simulación por Computador
4.
Nature ; 631(8019): 98-105, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38867037

RESUMEN

A key challenge in aerosol pollution studies and climate change assessment is to understand how atmospheric aerosol particles are initially formed1,2. Although new particle formation (NPF) mechanisms have been described at specific sites3-6, in most regions, such mechanisms remain uncertain to a large extent because of the limited ability of atmospheric models to simulate critical NPF processes1,7. Here we synthesize molecular-level experiments to develop comprehensive representations of 11 NPF mechanisms and the complex chemical transformation of precursor gases in a fully coupled global climate model. Combined simulations and observations show that the dominant NPF mechanisms are distinct worldwide and vary with region and altitude. Previously neglected or underrepresented mechanisms involving organics, amines, iodine oxoacids and HNO3 probably dominate NPF in most regions with high concentrations of aerosols or large aerosol radiative forcing; such regions include oceanic and human-polluted continental boundary layers, as well as the upper troposphere over rainforests and Asian monsoon regions. These underrepresented mechanisms also play notable roles in other areas, such as the upper troposphere of the Pacific and Atlantic oceans. Accordingly, NPF accounts for different fractions (10-80%) of the nuclei on which cloud forms at 0.5% supersaturation over various regions in the lower troposphere. The comprehensive simulation of global NPF mechanisms can help improve estimation and source attribution of the climate effects of aerosols.

5.
Environ Sci Atmos ; 4(5): 531-546, 2024 May 16.
Artículo en Inglés | MEDLINE | ID: mdl-38764888

RESUMEN

Iodine oxoacids are recognised for their significant contribution to the formation of new particles in marine and polar atmospheres. Nevertheless, to incorporate the iodine oxoacid nucleation mechanism into global simulations, it is essential to comprehend how this mechanism varies under various atmospheric conditions. In this study, we combined measurements from the CLOUD (Cosmic Leaving OUtdoor Droplets) chamber at CERN and simulations with a kinetic model to investigate the impact of temperature, ionisation, and humidity on iodine oxoacid nucleation. Our findings reveal that ion-induced particle formation rates remain largely unaffected by changes in temperature. However, neutral particle formation rates experience a significant increase when the temperature drops from +10 °C to -10 °C. Running the kinetic model with varying ionisation rates demonstrates that the particle formation rate only increases with a higher ionisation rate when the iodic acid concentration exceeds 1.5 × 107 cm-3, a concentration rarely reached in pristine marine atmospheres. Consequently, our simulations suggest that, despite higher ionisation rates, the charged cluster nucleation pathway of iodic acid is unlikely to be enhanced in the upper troposphere by higher ionisation rates. Instead, the neutral nucleation channel is likely to be the dominant channel in that region. Notably, the iodine oxoacid nucleation mechanism remains unaffected by changes in relative humidity from 2% to 80%. However, under unrealistically dry conditions (below 0.008% RH at +10 °C), iodine oxides (I2O4 and I2O5) significantly enhance formation rates. Therefore, we conclude that iodine oxoacid nucleation is the dominant nucleation mechanism for iodine nucleation in the marine and polar boundary layer atmosphere.

6.
Artículo en Inglés | MEDLINE | ID: mdl-38728178

RESUMEN

A Gram-negative, facultative anaerobic, non-motile and rod-shaped bacterium, designated 10c7w1T, was isolated from a human gastrointestinal tract. Colonies on agar plates were small, circular, smooth and beige. The optimal growth conditions were determined to be 37 °C, pH 7.0-7.5 and 0 % (w/v) NaCl. Comparative analysis of complete 16S rRNA gene sequences revealed that strain 10c7w1T showed the highest sequence similarity of 95.8 % to Ottowia beijingensis MCCC 1A01410T, followed by Ottowia thiooxydans (95.2 %) JCM 11629T. The average amino acid identity values between 10c7w1T and O. beijingensis MCCC 1A01410T and O. thiooxydans JCM 11629T were above 60 % (71.4 and 69.5 %). The average nucleotide identity values between strain 10c7w1T and O. beijingensis MCCC 1A01410T and O. thiooxydans JCM 11629T were 76.9 and 72.5 %, respectively. The dominant fatty acids (≥10 %) were straight chain ones, with summed feature 3 (C16 : 1 ω7c/C16 : 1 ω6c), summed feature 8 (C18 : 1 ω7c/C18 : 1 ω6c) and C16 : 00 being the most abundant. Q-8 was the only respiratory quinone. The major polar lipids of strain 10c7w1T were phosphatidylethanolamine, diphosphatidylglycerol and unknown lipids. The DNA G+C content of strain 10c7w1T was 63.6 mol%. On the basis of phylogenetic, phenotypic and chemotaxonomic data, strain 10c7w1T is considered to represent a novel species within the genus Ottowia, for which the name Ottowia cancrivicina sp. nov. is proposed. The type strain is 10c7w1T (=MCCC 1H01399T=KCTC 92200T).


Asunto(s)
Técnicas de Tipificación Bacteriana , Composición de Base , ADN Bacteriano , Ácidos Grasos , Filogenia , ARN Ribosómico 16S , Análisis de Secuencia de ADN , Estómago , ARN Ribosómico 16S/genética , Ácidos Grasos/química , Humanos , ADN Bacteriano/genética , Estómago/microbiología , Hibridación de Ácido Nucleico , Ubiquinona , Fosfolípidos/química
7.
ACS Nano ; 18(23): 15107-15113, 2024 Jun 11.
Artículo en Inglés | MEDLINE | ID: mdl-38819119

RESUMEN

Superconducting-based electronic devices have shown great potential for future quantum computing applications. One key building block device is a superconducting field-effect transistor based on a superconductor-semiconductor-superconductor Josephson-junction (JJ) with a gate-tunable semiconducting channel. However, the performance of such devices is highly dependent on the quality of the superconductor to semiconductor interface. In this study, we present an alternative method to obtain a high-quality interface by using intimate contact. We investigate the proximity-induced superconductivity in chiral crystal tellurium (Te) and fabricate a PdxTe-Te-PdxTe JJ with an ambipolar supercurrent that is gate-tunable and exhibits multiple Andreev reflections. The semiconducting two-dimensional Te single crystal is grown hydrothermally and partially converted to superconducting PdxTe by controlled annealing. Our work demonstrates a promising path for realizing controllable superconducting electronic devices with high-quality superconducting interfaces; thus, we can continue to advance the field of quantum computing and other interface-based technologies.

8.
Environ Res ; 252(Pt 4): 119055, 2024 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-38710429

RESUMEN

Application of biochar and inoculation with specific microbial strains offer promising approaches for addressing atrazine contamination in agricultural soils. However, determining the optimal method necessitates a comprehensive understanding of their effects under similar conditions. This study aimed to evaluate the effectiveness of biochar and Paenarthrobacter sp. AT5, a bacterial strain known for its ability to degrade atrazine, in reducing atrazine-related risks to soybean crops and influencing bacterial communities. Both biochar and strain AT5 significantly improved atrazine degradation in both planted and unplanted soils, with the most substantial reduction observed in soils treated with strain AT5. Furthermore, bioaugmentation with strain AT5 outperformed biochar in enhancing soybean growth, photosynthetic pigments, and antioxidant defenses. While biochar promoted higher soil bacterial diversity compared to strain AT5, the latter selectively enriched specific bacterial populations. Additionally, soil inoculated with strain AT5 displayed a notable increase in the abundance of key genes associated with atrazine degradation (trzN, atzB, and atzC), surpassing the effects observed with biochar addition, thus highlighting its effectiveness in mitigating atrazine risks in soil.


Asunto(s)
Atrazina , Biodegradación Ambiental , Carbón Orgánico , Glycine max , Herbicidas , Microbiología del Suelo , Contaminantes del Suelo , Atrazina/toxicidad , Glycine max/microbiología , Glycine max/efectos de los fármacos , Contaminantes del Suelo/toxicidad , Herbicidas/toxicidad , Suelo/química , Bacterias/efectos de los fármacos , Bacterias/genética , Bacterias/metabolismo
9.
Vaccine ; 42(19): 4072-4080, 2024 Jul 25.
Artículo en Inglés | MEDLINE | ID: mdl-38782664

RESUMEN

AIM: From the perspective of doctor-patient communication, this research used multiple methods combined natural language processing (NLP), a cross-sectional survey and an online experiment to investigated how risk perception influenced people's vaccination intention. METHODS: In Study 1, we used Python to crawl 335,045 comments about COVID-19 vaccine published in a social media platform Sina Weibo (equivalent of Twitter in China) from 31 December 2020 to 31 December 2021. Text analysis and sentiment analysis was used to examine how vaccination intention, as measured by linguistic features from the LIWC dictionary, changed with individuals' perceptions of pandemic risk. In Study 2, we adopted a cross-sectional questionnaire survey to further test the relation of risk perception, vaccination intention, trust in physicians, and perceived medical recommendations in a Chinese sample (n = 386). In Study 3, we conducted an online experiment where we recruited 127 participants with high trust in physicians and 127 participants with low trust, and subsequently randomly allocated them into one of three conditions: control, rational recommendation, or perceptual recommendation. RESULTS: Text and sentiment analysis revealed that the use of negative words towards COVID-19 vaccine had a significant decrease at high (vs. low) risk perception level time (Study 1). Trust in physicians mediated the effect of risk perception on vaccination intention and this effect was reinforced for participants with low (vs. high) level of perceived medical recommendation (Study 2), especially for the rational (vs. perceptual) recommendation condition (Study 3). CONCLUSION: Risk perception increased vaccination intention through the mediating effect of trust in physicians and the moderating effect of perceived medical recommendations. Rational (vs. perceptual) recommendation is more effective in increasing intention to get vaccinated in people with low trust in physicians.


Asunto(s)
Vacunas contra la COVID-19 , COVID-19 , Intención , Relaciones Médico-Paciente , Confianza , Vacunación , Humanos , Estudios Transversales , Masculino , Femenino , Vacunación/psicología , Vacunas contra la COVID-19/administración & dosificación , COVID-19/prevención & control , COVID-19/psicología , Adulto , Confianza/psicología , Encuestas y Cuestionarios , Persona de Mediana Edad , China , Comunicación , Medios de Comunicación Sociales , SARS-CoV-2/inmunología , Adulto Joven , Procesamiento de Lenguaje Natural
10.
Int J Mol Sci ; 25(7)2024 Mar 22.
Artículo en Inglés | MEDLINE | ID: mdl-38612393

RESUMEN

Cardiovascular diseases are a leading cause of morbidity and mortality world-wide. While many factors like smoking, hypertension, diabetes, dyslipidaemia, a sedentary lifestyle, and genetic factors can predispose to cardiovascular diseases, the natural process of aging is by itself a major determinant of the risk. Cardiac aging is marked by a conglomerate of cellular and molecular changes, exacerbated by age-driven decline in cardiac regeneration capacity. Although the phenotypes of cardiac aging are well characterised, the underlying molecular mechanisms are far less explored. Recent advances unequivocally link cardiovascular aging to the dysregulation of critical signalling pathways in cardiac fibroblasts, which compromises the critical role of these cells in maintaining the structural and functional integrity of the myocardium. Clearly, the identification of cardiac fibroblast-specific factors and mechanisms that regulate cardiac fibroblast function in the senescent myocardium is of immense importance. In this regard, recent studies show that Discoidin domain receptor 2 (DDR2), a collagen-activated receptor tyrosine kinase predominantly located in cardiac fibroblasts, has an obligate role in cardiac fibroblast function and cardiovascular fibrosis. Incisive studies on the molecular basis of cardiovascular aging and dysregulated fibroblast function in the senescent heart would pave the way for effective strategies to mitigate cardiovascular diseases in a rapidly growing elderly population.


Asunto(s)
Enfermedades Cardiovasculares , Hipertensión , Anciano , Humanos , Enfermedades Cardiovasculares/genética , Corazón , Miocardio , Fibroblastos
11.
PLoS Comput Biol ; 20(4): e1012068, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38683860

RESUMEN

Cancer development is driven by an accumulation of a small number of driver genetic mutations that confer the selective growth advantage to the cell, while most passenger mutations do not contribute to tumor progression. The identification of these driver genes responsible for tumorigenesis is a crucial step in designing effective cancer treatments. Although many computational methods have been developed with this purpose, the majority of existing methods solely provided a single driver gene list for the entire cohort of patients, ignoring the high heterogeneity of driver events across patients. It remains challenging to identify the personalized driver genes. Here, we propose a novel method (PDRWH), which aims to prioritize the mutated genes of a single patient based on their impact on the abnormal expression of downstream genes across a group of patients who share the co-mutation genes and similar gene expression profiles. The wide experimental results on 16 cancer datasets from TCGA showed that PDRWH excels in identifying known general driver genes and tumor-specific drivers. In the comparative testing across five cancer types, PDRWH outperformed existing individual-level methods as well as cohort-level methods. Our results also demonstrated that PDRWH could identify both common and rare drivers. The personalized driver profiles could improve tumor stratification, providing new insights into understanding tumor heterogeneity and taking a further step toward personalized treatment. We also validated one of our predicted novel personalized driver genes on tumor cell proliferation by vitro cell-based assays, the promoting effect of the high expression of Low-density lipoprotein receptor-related protein 1 (LRP1) on tumor cell proliferation.


Asunto(s)
Biología Computacional , Mutación , Neoplasias , Medicina de Precisión , Humanos , Neoplasias/genética , Biología Computacional/métodos , Medicina de Precisión/métodos , Perfilación de la Expresión Génica/métodos , Regulación Neoplásica de la Expresión Génica/genética , Modelos Genéticos , Bases de Datos Genéticas
12.
Zool Res ; 45(2): 329-340, 2024 Mar 18.
Artículo en Inglés | MEDLINE | ID: mdl-38485503

RESUMEN

The leopard coral grouper ( Plectropomus leopardus) is a species of significant economic importance. Although artificial cultivation of P. leopardus has thrived in recent decades, the advancement of selective breeding has been hindered by the lack of comprehensive population genomic data. In this study, we identified over 8.73 million single nucleotide polymorphisms (SNPs) through whole-genome resequencing of 326 individuals spanning six distinct groups. Furthermore, we categorized 226 individuals with high-coverage sequencing depth (≥14×) into eight clusters based on their genetic profiles and phylogenetic relationships. Notably, four of these clusters exhibited pronounced genetic differentiation compared with the other populations. To identify potentially advantageous loci for P. leopardus, we examined genomic regions exhibiting selective sweeps by analyzing the nucleotide diversity ( θπ) and fixation index ( F ST) in these four clusters. Using these high-coverage resequencing data, we successfully constructed the first haplotype reference panel specific to P. leopardus. This achievement holds promise for enabling high-quality, cost-effective imputation methods. Additionally, we combined low-coverage sequencing data with imputation techniques for a genome-wide association study, aiming to identify candidate SNP loci and genes associated with growth traits. A significant concentration of these genes was observed on chromosome 17, which is primarily involved in skeletal muscle and embryonic development and cell proliferation. Notably, our detailed investigation of growth-related SNPs across the eight clusters revealed that cluster 5 harbored the most promising candidate SNPs, showing potential for genetic selective breeding efforts. These findings provide a robust toolkit and valuable insights into the management of germplasm resources and genome-driven breeding initiatives targeting P. leopardus.


Asunto(s)
Antozoos , Lubina , Humanos , Animales , Filogenia , Estudio de Asociación del Genoma Completo/veterinaria , Genoma
13.
Int J Mol Sci ; 25(4)2024 Feb 11.
Artículo en Inglés | MEDLINE | ID: mdl-38396857

RESUMEN

The differentiation and developmental trajectory of fish gonads, significantly important for fish breeding, culture, and production, has long been a focal point in the fields of fish genetics and developmental biology. However, the mechanism of gonadal differentiation in leopard coral grouper (Plectropomus leopardus) remains unclear. This study investigates the 17ß-Hydroxysteroid Dehydrogenase (Hsd17b) gene family in P. leopardus, with a focus on gene characterization, expression profiling, and functional analysis. The results reveal that the P. leopardus's Hsd17b gene family comprises 11 members, all belonging to the SDR superfamily. The amino acid similarity is only 12.96%, but conserved motifs, such as TGxxxGxG and S-Y-K, are present in these genes. Hsd17b12a and Hsd17b12b are unique homologs in fish, and chromosomal localization has confirmed that they are not derived from different transcripts of the same gene, but rather are two independent genes. The Hsd17b family genes, predominantly expressed in the liver, heart, gills, kidneys, and gonads, are involved in synthesizing or metabolizing sex steroid hormones and neurotransmitters, with their expression patterns during gonadal development categorized into three distinct categories. Notably, Hsd17b4 and Hsd17b12a were highly expressed in the testis and ovary, respectively, suggesting their involvement in the development of reproductive cells in these organs. Fluorescence in situ hybridization (FISH) further indicated specific expression sites for these genes, with Hsd17b4 primarily expressed in germ stem cells and Hsd17b12a in oocytes. This comprehensive study provides foundational insights into the role of the Hsd17b gene family in gonadal development and steroidogenesis in P. leopardus, contributing to the broader understanding of fish reproductive biology and aquaculture breeding.


Asunto(s)
17-Hidroxiesteroide Deshidrogenasas , Lubina , Animales , Masculino , Femenino , Hibridación Fluorescente in Situ , Gónadas/metabolismo , Testículo/metabolismo
14.
BMC Genomics ; 25(1): 210, 2024 Feb 26.
Artículo en Inglés | MEDLINE | ID: mdl-38408914

RESUMEN

BACKGROUND: Due to its enormous biomass, Antarctic krill (Euphausia superba) plays a crucial role in the Antarctic Ocean ecosystem. In recent years, Antarctic krill has found extensive application in aquaculture, emerging as a sustainable source of aquafeed with ideal nutritional profiles. However, a comprehensive study focused on the detailed effects of dietary Antarctic krill on aquaculture animals, especially farmed marine fishes, is yet to be demonstrated. RESULTS: In this study, a comparative experiment was performed using juvenile P. leopardus, fed with diets supplemented with Antarctic krill (the krill group) or without Antarctic krill (the control group). Histological observation revealed that dietary Antarctic krill could reduce lipid accumulation in the liver while the intestine exhibited no obvious changes. Enzyme activity measurements demonstrated that dietary Antarctic krill had an inhibitory effect on oxidative stress in both the intestine and the liver. By comparative transcriptome analysis, a total of 1,597 and 1,161 differentially expressed genes (DEGs) were identified in the intestine and liver, respectively. Functional analysis of the DEGs showed multiple enriched terms significantly related to cholesterol metabolism, antioxidants, and immunity. Furthermore, the expression profiles of representative DEGs, such as dhcr7, apoa4, sc5d, and scarf1, were validated by qRT-PCR and fluorescence in situ hybridization. Finally, a comparative transcriptome analysis was performed to demonstrate the biased effects of dietary Antarctic krill and astaxanthin on the liver of P. leopardus. CONCLUSIONS: Our study demonstrated that dietary Antarctic krill could reduce lipid accumulation in the liver of P. leopardus, enhance antioxidant capacities in both the intestine and liver, and exhibit molecular-level improvements in lipid metabolism, immunity, and antioxidants. It will contribute to understanding the protective effects of Antarctic krill in P. leopardus and provide insights into aquaculture nutritional strategies.


Asunto(s)
Lubina , Euphausiacea , Animales , Antioxidantes , Euphausiacea/genética , Ecosistema , Hibridación Fluorescente in Situ , Perfilación de la Expresión Génica , Dieta , Lubina/genética , Lípidos , Regiones Antárticas
15.
Environ Sci Atmos ; 4(2): 265-274, 2024 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-38371605

RESUMEN

Aerosols formed and grown by gas-to-particle processes are a major contributor to smog and haze in megacities, despite the competition between growth and loss rates. Rapid growth rates from ammonium nitrate formation have the potential to sustain particle number in typical urban polluted conditions. This process requires supersaturation of gas-phase ammonia and nitric acid with respect to ammonium nitrate saturation ratios. Urban environments are inhomogeneous. In the troposphere, vertical mixing is fast, and aerosols may experience rapidly changing temperatures. In areas close to sources of pollution, gas-phase concentrations can also be highly variable. In this work we present results from nucleation experiments at -10 °C and 5 °C in the CLOUD chamber at CERN. We verify, using a kinetic model, how long supersaturation is likely to be sustained under urban conditions with temperature and concentration inhomogeneities, and the impact it may have on the particle size distribution. We show that rapid and strong temperature changes of 1 °C min-1 are needed to cause rapid growth of nanoparticles through ammonium nitrate formation. Furthermore, inhomogeneous emissions of ammonia in cities may also cause rapid growth of particles.

16.
Gene ; 901: 148166, 2024 Apr 05.
Artículo en Inglés | MEDLINE | ID: mdl-38242379

RESUMEN

Leopard coral grouper (Plectropomus leopardus) is a type of hermaphrodite fish, but the mechanisms of gonadal development and gametogenesis remain unclear. In the present study, we performed histological observation and transcriptomic analysis during the process of sexual differentiation in P. leopardus. According to the histological results, sexual differentiation was completed at 15 months old, developed synchronously in male and female individuals at 2 years old, and matured synchronously at 3 years old. Comparative transcriptomic analyses showed that the gonadal had differentiated by 15 months old, with enrichment of pathways associated with cell proliferation, transcriptional metabolism, and germline stem cell differentiation. Furthermore, cilium movement and fatty acid anabolism, which are associated with spermatogenesis and oocyte growth, were significantly enriched at 3 years old. In addition, key genes associated with male and female sex differentiation, such as amh, dmrt1, dmrt2a, zp4, sox3, gdf9, and gsdf, were identified by weighted gene co-expression network analysis (WGCNA). Finally, the localization and expression of the key genes amh and sox3 were observed in different cell types within the testes and ovaries, reflecting the development of the testes and ovaries, respectively. All the evidence indicates that P. leopardus is a hermaphrodite and synchronously sexually mature fish. Our study complements the gonadal development patterns of hermaphroditic fish by providing new insights into the molecular mechanisms underlying sexual differentiation and sex change in hermaphroditic groupers.


Asunto(s)
Lubina , Animales , Femenino , Masculino , Lubina/genética , Gónadas , Testículo/metabolismo , Ovario/metabolismo , Perfilación de la Expresión Génica , Transcriptoma
17.
Environ Sci Technol ; 58(3): 1601-1614, 2024 Jan 23.
Artículo en Inglés | MEDLINE | ID: mdl-38185880

RESUMEN

Highly oxygenated organic molecules (HOMs) are a major source of new particles that affect the Earth's climate. HOM production from the oxidation of volatile organic compounds (VOCs) occurs during both the day and night and can lead to new particle formation (NPF). However, NPF involving organic vapors has been reported much more often during the daytime than during nighttime. Here, we show that the nitrate radicals (NO3), which arise predominantly at night, inhibit NPF during the oxidation of monoterpenes based on three lines of observational evidence: NPF experiments in the CLOUD (Cosmics Leaving OUtdoor Droplets) chamber at CERN (European Organization for Nuclear Research), radical chemistry experiments using an oxidation flow reactor, and field observations in a wetland that occasionally exhibits nocturnal NPF. Nitrooxy-peroxy radicals formed from NO3 chemistry suppress the production of ultralow-volatility organic compounds (ULVOCs) responsible for biogenic NPF, which are covalently bound peroxy radical (RO2) dimer association products. The ULVOC yield of α-pinene in the presence of NO3 is one-fifth of that resulting from ozone chemistry alone. Even trace amounts of NO3 radicals, at sub-parts per trillion level, suppress the NPF rate by a factor of 4. Ambient observations further confirm that when NO3 chemistry is involved, monoterpene NPF is completely turned off. Our results explain the frequent absence of nocturnal biogenic NPF in monoterpene (α-pinene)-rich environments.


Asunto(s)
Contaminantes Atmosféricos , Monoterpenos Bicíclicos , Ozono , Compuestos Orgánicos Volátiles , Monoterpenos/química , Nitratos/química , Aerosoles/análisis , Compuestos Orgánicos Volátiles/química
18.
J Colloid Interface Sci ; 659: 868-877, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38219305

RESUMEN

A recyclable hard-template method is proposed to exploit spindle-shaped hollow nitrogen-doped amorphous carbon (h-NAC) with a large number of short-range curved carbon fragments as anodes for lithium/sodium ion batteries (LIBs/SIBs). Besides providing adsorption sites due to the high existence of oxygen-containing functional groups (CO and COOH), the heavily exposed edge regions also provide a favorable storage environment with high adsorption energy for Li+/Na+ due to their short-range curved structure. Importantly, the etching solution of hard templates can be recycled to generate the FeOOH nanospindles as a precursor through a simple chemical titration, which supplies a new idea for the green preparation of hollow materials. The h-NAC electrode is proven to be bifunctional for storing lithium and sodium ions, displaying favorable rate capability (255 mAh g-1 and 106 mAh g-1 at 5 A g-1 for LIBs and SIBs, respectively). After 1000 cycles at 1 A g-1, the reproducible capacities of the LIBs and SIBs kept 496 mAh g-1 and 181 mAh g-1, respectively.

19.
Science ; 382(6676): 1308-1314, 2023 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-38096284

RESUMEN

The main nucleating vapor in the atmosphere is thought to be sulfuric acid (H2SO4), stabilized by ammonia (NH3). However, in marine and polar regions, NH3 is generally low, and H2SO4 is frequently found together with iodine oxoacids [HIOx, i.e., iodic acid (HIO3) and iodous acid (HIO2)]. In experiments performed with the CERN CLOUD (Cosmics Leaving OUtdoor Droplets) chamber, we investigated the interplay of H2SO4 and HIOx during atmospheric particle nucleation. We found that HIOx greatly enhances H2SO4(-NH3) nucleation through two different interactions. First, HIO3 strongly binds with H2SO4 in charged clusters so they drive particle nucleation synergistically. Second, HIO2 substitutes for NH3, forming strongly bound H2SO4-HIO2 acid-base pairs in molecular clusters. Global observations imply that HIOx is enhancing H2SO4(-NH3) nucleation rates 10- to 10,000-fold in marine and polar regions.

20.
Bioinformatics ; 39(12)2023 12 01.
Artículo en Inglés | MEDLINE | ID: mdl-38065693

RESUMEN

MOTIVATION: Cancer is caused by the accumulation of somatic mutations in multiple pathways, in which driver mutations are typically of the properties of high coverage and high exclusivity in patients. Identifying cancer driver genes has a pivotal role in understanding the mechanisms of oncogenesis and treatment. RESULTS: Here, we introduced MaxCLK, an algorithm for identifying cancer driver genes, which was developed by an integrated analysis of somatic mutation data and protein-protein interaction (PPI) networks and further improved by an information entropy index. Tested on pancancer and single cancers, MaxCLK outperformed other existing methods with higher accuracy. About pancancer, we predicted 154 driver genes and 787 driver modules. The analysis of co-occurrence and exclusivity between modules and pathways reveals the correlation of their combinations. Overall, our study has deepened the understanding of driver mechanism in PPI topology and found novel driver genes. AVAILABILITY AND IMPLEMENTATION: The source codes for MaxCLK are freely available at https://github.com/ShandongUniversityMasterMa/MaxCLK-main.


Asunto(s)
Biología Computacional , Neoplasias , Humanos , Entropía , Biología Computacional/métodos , Mutación , Redes Reguladoras de Genes , Neoplasias/genética , Algoritmos
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