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1.
Plant Phenomics ; 6: 0200, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38978968

RESUMEN

Efficient and accurate acquisition of the rice grain protein content (GPC) is important for selecting high-quality rice varieties, and remote sensing technology is an attractive potential method for this task. However, the majority of multispectral sensors are poor predictors of GPC due to their broad spectral bands. Hyperspectral technology provides a new analytical technology for bridging the gap between phenomics and genomics. However, the small size of typical datasets is a constraint for model construction for estimating GPC, limiting their accuracy and reducing their ability to generalize to a wide range of varieties. In this study, we used hyperspectral data of rice grains from 515 japonica varieties and deep convolution generative adversarial networks (DCGANs) to generate simulated data to improve the model accuracy. Features sensitive to GPC were extracted after applying a continuous wavelet transform (CWT), and the estimated GPC model was constructed by partial least squares regression (PLSR). Finally, a genome-wide association study (GWAS) was applied to the measured and generated datasets to detect GPC loci. The results demonstrated that the simulated GPC values generated after 8,000 epochs were closest to the measured values. The wavelet feature (WF1743, 2), obtained from the data with the addition of 200 simulated samples, exhibited the highest GPC estimation accuracy (R 2 = 0.58 and RRMSE = 6.70%). The GWAS analysis showed that the estimated values based on the simulated data detected the same loci as the measured values, including the OsmtSSB1L gene related to grain storage protein. This study provides a new technique for the efficient genetic study of phenotypic traits in rice based on hyperspectral technology.

2.
Eur J Pharmacol ; 977: 176672, 2024 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-38849041

RESUMEN

OBJECTIVE: Abscisic acid (ABA) is a phytohormone that inhibits airway inflammation in acute respiratory distress syndrome (ARDS) mouse models. However, the molecular mechanism underlying this phenomenon remains unclear. METHODS: Serum ABA level in patients and mice was measured via liquid chromatography-tandem mass spectrometry (LC-MS/MS). In-depth molecular mechanism was investigated through transmission electron microscopy, RNA-sequencing, and molecular docking in ARDS mice and cultured primary alveolar macrophages (AMs). RESULTS: We found that the serum ABA level was remarkably decreased in ARDS mice and patients. ABA inhibited lipopolysaccharide (LPS)-induced airway inflammation in mice; moreover, it downregulated genes associated with pyroptosis, as shown by RNA-sequencing and lung protein immunoblots. ABA inhibited the formation of membrane pores in AMs and suppressed the cleavage of gasdermin D (GSDMD) and the activation of caspase-11 and caspase-1 in vivo and in vitro; however, the overexpression of caspase-11 reversed the protective effect of ABA on LPS-induced pyroptosis of primary AMs. ABA inhibited intra-AM LPS accumulation while increasing the level of acyloxyacyl hydrolase (AOAH) in AMs, whereas AOAH deficiency abrogated the suppressive action of ABA on inflammation, pyroptosis, and intra-AM LPS accumulation in vivo and in vitro. Importantly, ABA promoted its intracellular receptor lanthionine C-like receptor 2 interacting with transcription factor peroxisome proliferator-activated receptor γ, which ultimately leading to increase AOAH expression to inactivate LPS and inhibit pyroptosis in AMs. CONCLUSIONS: ABA protected against LPS-induced lung injury by inhibiting pyroptosis in AMs via proliferator-activated receptor γ-mediated AOAH expression.


Asunto(s)
Ácido Abscísico , Macrófagos Alveolares , Piroptosis , Síndrome de Dificultad Respiratoria , Piroptosis/efectos de los fármacos , Animales , Ácido Abscísico/farmacología , Ratones , Macrófagos Alveolares/efectos de los fármacos , Macrófagos Alveolares/metabolismo , Síndrome de Dificultad Respiratoria/tratamiento farmacológico , Síndrome de Dificultad Respiratoria/patología , Síndrome de Dificultad Respiratoria/metabolismo , Síndrome de Dificultad Respiratoria/inducido químicamente , Masculino , Humanos , Lipopolisacáridos/farmacología , PPAR gamma/metabolismo , Regulación hacia Arriba/efectos de los fármacos , Ratones Endogámicos C57BL , Femenino , Modelos Animales de Enfermedad
3.
Nat Genet ; 56(7): 1516-1526, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38872029

RESUMEN

Excessive nitrogen promotes the formation of nonproductive tillers in rice, which decreases nitrogen use efficiency (NUE). Developing high-NUE rice cultivars through balancing nitrogen uptake and the formation of productive tillers remains a long-standing challenge, yet how these two processes are coordinated in rice remains elusive. Here we identify the transcription factor OsGATA8 as a key coordinator of nitrogen uptake and tiller formation in rice. OsGATA8 negatively regulates nitrogen uptake by repressing transcription of the ammonium transporter gene OsAMT3.2. Meanwhile, it promotes tiller formation by repressing the transcription of OsTCP19, a negative modulator of tillering. We identify OsGATA8-H as a high-NUE haplotype with enhanced nitrogen uptake and a higher proportion of productive tillers. The geographical distribution of OsGATA8-H and its frequency change in historical accessions suggest its adaption to the fertile soil. Overall, this study provides molecular and evolutionary insights into the regulation of NUE and facilitates the breeding of rice cultivars with higher NUE.


Asunto(s)
Regulación de la Expresión Génica de las Plantas , Haplotipos , Nitrógeno , Oryza , Proteínas de Plantas , Oryza/genética , Oryza/crecimiento & desarrollo , Oryza/metabolismo , Nitrógeno/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Factores de Transcripción/metabolismo , Factores de Transcripción/genética , Proteínas de Transporte de Catión/genética , Proteínas de Transporte de Catión/metabolismo
4.
Plants (Basel) ; 13(5)2024 Mar 06.
Artículo en Inglés | MEDLINE | ID: mdl-38475591

RESUMEN

Wx is the key gene that controls amylose content (AC), and various alleles have been found in rice populations. Wxb is the major allele in japonica and produces moderate AC (15~18%). It was recently found that editing the promoter of Wx could produce a series of alleles that have different Wx activities. Although some studies have edited the promoter, few studies have focused on the natural variations in Wx. Here, we used the Rice3K database to investigate variations in the Wx promoter and found that the allele Wx1764178 (A/G) has a higher LD (linkage disequilibrium) with the two key SNPs (1765751, T/G; 1768006, A/C), which could produce different Wx alleles and influence AC, as reported previously. Further study showed that the Wx1764178 allele (A/G) is functional and influences the expression of Wx positively. Editing the A allele using CRISPR‒Cas9 produced 36 and 3 bp deletions and caused a decrease in the expression of Wx. The apparent amylose content (AAC) in the edited lines was decreased by 7.09% and 11.50% compared with that of the wild type, which was the japonica variety Nipponbare with Wxb and the A allele at 1764178, while a complementary line with the G allele showed a lower AAC than the A allele with no effect on other agronomic traits. The AAC of the edited lines showed a higher increase than that of the wild type (Nipponbare, Wxb) in low-nitrogen conditions relative to high-nitrogen conditions. We also developed a dCAPS marker to identify the allele and found that the G allele has widely been used (82.95%) in japonica-bred varieties from Jiangsu Province, China. Overall, we found a functional allele (Wx1764178, A/G) in the Wx promoter that could affect AAC in japonica cultivars and be developed as markers for quality improvement in rice breeding programs.

5.
Chemosphere ; 349: 140875, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38065260

RESUMEN

Bromate (BrO3-), a worldwide regulated by-product after ozone disinfection, is often detected in bromide-containing water, and has a strict limit of 10 µg L-1 in potable water. BrO3- degradation by advanced reduction processes (ARPs) has gained much attention because of efficient removal and easy integration with ultraviolet disinfection (UV at 254 nm). In the vacuum UV (VUV, 185/254 nm)/sulfite system, the elimination kinetics of BrO3- increased by 9-fold and 15-fold comparing with VUV alone and UV/sulfite system. This study further demonstrated the hydrated electron (eaq-) works as the dominant species in BrO3- degradation in alkaline solution, while in the acidic solution the H• became a secondary reactive species besides eaq-. Hence, the influences of pH, sulfite concentration, dissolved gas and water matrix on effectiveness of degradation kinetics of BrO3- was explored in details. With increasing pH, the proportion of SO32- species increased and even became the major ones, which also correlated well with the kobs (min-1) of BrO3- degradation. The stability of eaq- also climbs with increasing pH, while that of H• drops significantly. Higher sulfite dosage favored a more rapid degradation of BrO3-. The presence of dissolved oxygen inhibited BrO3- removal due to the scavenging effect of O2 toward eaq- and transformed VUV/sulfite-based ARP to an advanced oxidation process (AOP), which was ineffective for BrO3- removal. BrO3- removal was inhibited to varying degrees after anions (e.g., bicarbonate (HCO3-), chloride (Cl-), nitrate (NO3-)) and humic acid (HA) being added.


Asunto(s)
Agua Potable , Contaminantes Químicos del Agua , Purificación del Agua , Bromatos , Vacio , Contaminantes Químicos del Agua/análisis , Oxidación-Reducción , Sulfitos , Halógenos , Rayos Ultravioleta
6.
Front Cardiovasc Med ; 10: 1279177, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-38028439

RESUMEN

Primary cardiac tumors are exceptionally rare, with malignant tumor occurrences ranging from 0.0017% to 0.28%. Among these, primary cardiac angiosarcoma (PCA) stands as the most prevalent malignancy, primarily impacting the right cardiac system. In this case report, we present the instance of a 44-year-old woman who recently exhibited acute chest discomfort and was subsequently diagnosed with a microangiosarcoma within the right atrium and superior vena cava. Diagnostic modalities including chest x-rays, CT, MRI, and PET-CT were instrumental in pinpointing the tumor's location and nature. Surgical excision followed by pathological and immunological examinations confirmed the diagnosis. The patient's recovery post-surgery has been encouraging, with successful follow-up chemoradiotherapy administered. Despite advancements, devising optimal strategies for enhancing patient survival and quality of life in angiosarcoma cases remains a pressing research challenge.

7.
Plants (Basel) ; 12(21)2023 Oct 30.
Artículo en Inglés | MEDLINE | ID: mdl-37960079

RESUMEN

Salt is harmful to crop production. Therefore, it is important to understand the mechanism of salt tolerance in rice. CIPK genes have various functions, including regulating salt tolerance and other types of stress and nitrogen use efficiency. In rice, OsCIPK24 is known to regulate salt tolerance, but other OsCIPKs could also function in salt tolerance. In this study, we identified another OsCIPK-OsCIPK9-that can regulate salt tolerance. Knockout of OsCIPK9 in rice could improve salt tolerance. Through expression analyses, OsCIPK9 was found to be mainly expressed in the roots and less expressed in mature leaves. Meanwhile, OsCIPK9 had the highest expression 6 h after salt treatment. In addition, we proved the interaction between OsCIPK9 and OsSOS3. The RNA-seq data showed that OsCIPK9 strongly responded to salt treatment, and the transporters related to salt tolerance may be downstream genes of OsCIPK9. Finally, haplotype analyses revealed that Hap6 and Hap8 mainly exist in indica, potentially providing a higher salt tolerance. Overall, a negative regulator of salt tolerance, OsCIPK9, which interacted with OsSOS3 similarly to OsCIPK24 and influenced salt-related transporters, was identified, and editing OsCIPK9 potentially could be helpful for breeding salt-tolerant rice.

8.
Heart Fail Rev ; 2023 Nov 09.
Artículo en Inglés | MEDLINE | ID: mdl-37943420

RESUMEN

Cardiovascular diseases (CVDs) represent a paramount global mortality concern, and their prevalence is on a relentless ascent. Despite the effectiveness of contemporary medical interventions in mitigating CVD-related fatality rates and complications, their efficacy remains curtailed by an array of limitations. These include the suboptimal efficiency of direct cell injection and an inherent disequilibrium between the demand and availability of heart transplantations. Consequently, the imperative to formulate innovative strategies for cardiac regeneration therapy becomes unmistakable. Within this context, 3D bioprinting technology emerges as a vanguard contender, occupying a pivotal niche in the realm of tissue engineering and regenerative medicine. This state-of-the-art methodology holds the potential to fabricate intricate heart tissues endowed with multifaceted structures and functionalities, thereby engendering substantial promise. By harnessing the prowess of 3D bioprinting, it becomes plausible to synthesize functional cardiac architectures seamlessly enmeshed with the host tissue, affording a viable avenue for the restitution of infarcted domains and, by extension, mitigating the onerous yoke of CVDs. In this review, we encapsulate the myriad applications of 3D bioprinting technology in the domain of heart tissue regeneration. Furthermore, we usher in the latest advancements in printing methodologies and bioinks, culminating in an exploration of the extant challenges and the vista of possibilities inherent to a diverse array of approaches.

9.
Front Cardiovasc Med ; 10: 1233873, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37781309

RESUMEN

Congenital coronary artery fistula (CAF) represents a remarkable rarity within the realm of cardiovascular anomalies, characterized by an aberrant connection between coronary arteries and either cardiac chambers or major vessels. Clinical manifestations of CAFs often remain unspecified or may even be entirely absent, posing diagnostic challenges. Notably, patients harboring substantial CAFs may exhibit symptoms such as palpitations, chest tightness, and dyspnea. Although right-sided congenital CAFs are relatively prevalent, the occurrence of a CAF accompanied by a colossal pseudoaneurysm imposing compression upon the pulmonary vein is an exceedingly rare phenomenon. This exceptional case report delineates a singular fistula originating from the right coronary artery, extending its course to the right atrium, and remarkably featuring a substantial pseudoaneurysm exerting compression upon the right superior pulmonary vein. Therapeutic intervention encompassed surgical closure of the proximal artery and excision of the pseudoaneurysm, underscoring the complexity and criticality of managing such intricate cardiac anomalies to ensure optimal patient outcomes.

10.
Brain Behav ; 13(12): e3279, 2023 12.
Artículo en Inglés | MEDLINE | ID: mdl-37815202

RESUMEN

BACKGROUND: Cerebral small vessel disease (CSVD) is considered an age-related degenerative neurological disorder and the most common risk factor for vascular cognitive impairment (VCI). The amplitude of fluctuation of low frequency (ALFF) can detect altered intrinsic brain activity in CSVD. This study explored the static and dynamic ALFFs in the early stage of CSVD with (CSVD-M) or without (CSVD-W) mild cognitive impairment (MCI) in these patients and how these changes contribute to cognitive deterioration. METHODS: Thirty consecutive CSVD cases and 18 healthy controls (HC) were included in this study. All the participants underwent a 3D magnetization-prepared rapid gradient-echo (MPRAGE) sequence to obtain structural T1-weighted images. Simultaneous multislice imaging 5(SMS5) was used for resting-state functional MRI (rs-fMRI), and Data Processing and Analysis of Brain Imaging software helped determine static ALFF (sALFF). The dynamic ALFF (dALFF) was calculated using the sliding window method of DynamicBC software. Analysis of Covariance (ANCOVA) and two-sample t-test were used to evaluate the sALFF and temporal variability of dALFF among the three groups. The subjects were rated on a broad standard neuropsychological scale. Partial correlation analysis was used to evaluate the correlation between sALFF and dALFF variability and cognition (Bonferroni correction, statistical threshold set at p < .05). RESULTS: Compared with HCs, the CSVD-M group indicated decreased sALFF values in the bilateral cerebellum posterior lobe (CPL) and the left inferior Parietal Lobule (IPL), with increased sALFF values in the right SFG. For dALFF analysis, the CSVD-W group had significant dALFF variability in the right fusiform gyrus compared with HC. Moreover, the postcentral gyrus (PoCG) was significantly high in the CSVD-W group. While in the CSVD-M group, the bilateral paracentral lobules (PL) revealed significantly elevated dALFF variability and low dALFF variability in the left CPL and right IPL compared with HCs. The CSVD-M group had high dALFF variability in the bilateral PL but low dALFF variability in the left middle temporal gyrus (MTG) and right PoCG compared with the CSVD-W group. The partial correlation analysis indicated that dALFF variability in the left MTG was positively associated with EM (r = 0.713, p = .002) in CSVD-W and CSVD-M groups. In the groups with CSVD-M and HC, altered dALFF variability in the bilateral PL was negatively correlated with EM (r = -0.560, p = .002). CONCLUSION: There were significant changes in sALFF and dALFF variability in CSVD patients. Abnormal spontaneous static and dynamic ALFFs may provide new insights into cognitive dysfunction in CSVD with MCI and may be valuable biomarkers for early diagnosis.


Asunto(s)
Enfermedades de los Pequeños Vasos Cerebrales , Trastornos del Conocimiento , Disfunción Cognitiva , Humanos , Mapeo Encefálico/métodos , Encéfalo/diagnóstico por imagen , Disfunción Cognitiva/etiología , Disfunción Cognitiva/complicaciones , Enfermedades de los Pequeños Vasos Cerebrales/complicaciones , Enfermedades de los Pequeños Vasos Cerebrales/diagnóstico por imagen , Imagen por Resonancia Magnética/métodos
11.
Biomater Sci ; 11(19): 6403-6420, 2023 Sep 26.
Artículo en Inglés | MEDLINE | ID: mdl-37599608

RESUMEN

Cardiovascular diseases have remained the leading cause of death worldwide for the past 20 years. The current clinical therapeutic measures, including bypass surgery, stent implantation and pharmacotherapy, are not enough to repair the massive loss of cardiomyocytes after myocardial ischemia. Timely replenishment with functional myocardial tissue via biomedical engineering is the most direct and effective means to improve the prognosis and survival rate of patients. It is widely recognized that 4D printing technology introduces an additional dimension of time in comparison with traditional 3D printing. Additionally, in the context of 4D bioprinting, both the printed material and the resulting product are designed to be biocompatible, which will be the mainstream of bioprinting in the future. Thus, this review focuses on the application of 4D bioprinting in cardiovascular diseases, discusses the bottleneck of the development of 4D bioprinting, and finally looks forward to the future direction and prospect of this revolutionary technology.


Asunto(s)
Bioimpresión , Enfermedades Cardiovasculares , Humanos , Ingeniería de Tejidos/métodos , Materiales Biocompatibles , Enfermedades Cardiovasculares/terapia , Impresión Tridimensional , Andamios del Tejido
12.
Cell ; 186(17): 3577-3592.e18, 2023 08 17.
Artículo en Inglés | MEDLINE | ID: mdl-37499659

RESUMEN

Hybrid sterility restricts the utilization of superior heterosis of indica-japonica inter-subspecific hybrids. In this study, we report the identification of RHS12, a major locus controlling male gamete sterility in indica-japonica hybrid rice. We show that RHS12 consists of two genes (iORF3/DUYAO and iORF4/JIEYAO) that confer preferential transmission of the RHS12-i type male gamete into the progeny, thereby forming a natural gene drive. DUYAO encodes a mitochondrion-targeted protein that interacts with OsCOX11 to trigger cytotoxicity and cell death, whereas JIEYAO encodes a protein that reroutes DUYAO to the autophagosome for degradation via direct physical interaction, thereby detoxifying DUYAO. Evolutionary trajectory analysis reveals that this system likely formed de novo in the AA genome Oryza clade and contributed to reproductive isolation (RI) between different lineages of rice. Our combined results provide mechanistic insights into the genetic basis of RI as well as insights for strategic designs of hybrid rice breeding.


Asunto(s)
Tecnología de Genética Dirigida , Oryza , Hibridación Genética , Oryza/genética , Fitomejoramiento/métodos , Aislamiento Reproductivo , Infertilidad Vegetal
13.
Front Cardiovasc Med ; 10: 1129529, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37252122

RESUMEN

Rheumatic heart disease (RHD) is a widespread illness in developing countries. RHD causes 99% of mitral stenoses in adults and 25% of aortic regurgitation. However, it only causes 10% of stenoses of the tricuspid valve, and is almost always associated with left-side valvular lesions. Isolated right-side valves are rarely affected, but may result in severe rheumatic pulmonary regurgitation. Herein, we present a case of rheumatic right-sided valve disease with severe pulmonary valve contracture and regurgitation in a symptomatic patient, successfully managed by surgical valvular reconstruction with a tailored bileaflet bovine pericardial patch. The options for surgical approach are also discussed. To our knowledge, the presented rheumatic right-sided valve disease with severe pulmonary regurgitation is the first to be reported in the literature.

14.
Rice (N Y) ; 15(1): 48, 2022 Sep 24.
Artículo en Inglés | MEDLINE | ID: mdl-36152074

RESUMEN

BACKGROUND: Breeding of conventional and hybrid rice (Oryza sativa L.) have solved hunger problems and increased farmers' income in the world. Molecular markers have been widely used in marker-assisted breeding and identification of larger numbers of different bred varieties in the past decades. The recently developed SNP markers are applied for more stable and detectable compared with other markers. But the cost of genotyping lots SNPs is high. So, it is essential to select less representative SNPs and inexpensive detecting methods to lower the cost and accelerate variety identification and breeding process. KASP (Kompetitive Allele-Specific PCR) is a flexible method to detect the SNPs, and large number of KASP markers have been widely used in variety identification and breeding. However, the ability of less KASP markers on massive variety identification and breeding remains unknown. RESULTS: Here, 48 KASP markers were selected from 378 markers to classify and analyze 518 varieties including conventional and hybrid rice. Through analyzing the population structure, the 48 markers could almost represent the 378 markers. In terms of variety identification, the 48 KASP markers had a 100% discrimination rate in 53 conventional indica varieties and 193 hybrid varieties, while they could distinguish 89.1% conventional japonica rice from different breeding institutes. Two more markers added would increase the ratio from 68.38 to 77.94%. Additionally, the 48 markers could be used for classification of subpopulations in the bred variety. Also, 8 markers had almost completely different genotypes between japonica and indica, and 3 markers were found to be very important for japonica hybrid rice. In hybrid varieties, the heterozygosity of chromosomes 3, 6 and 11 was relatively higher than others. CONCLUSIONS: Our results showed that 48 KASP markers could be used to identify rice varieties, and the panel we tested could provide a database for breeders to identify new breeding lines. Also, the specific markers we found were useful for marker-assisted breeding in rice, including conventional and hybrid.

15.
Front Cardiovasc Med ; 9: 944393, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36061542

RESUMEN

Cardiovascular diseases remain the leading cause of death worldwide, particularly ischemic heart disease (IHD). It is also classified as incurable given the irreversible damage it causes to cardiomyocytes. Thus, myocardial tissue rejuvenation following ischemia is one of the global primary research concerns for scientists. Interestingly, the mammalian heart thrives after an injury during the embryonic or neonatal period; however, this ability disappears with increasing age. Previous studies have found that specific non-coding (nc) RNAs play a pivotal role in this process. Hence, the review herein summarizes the research on cardiomyocyte regenerative medicine in recent years and sets forth the biological functions and mechanisms of the micro (mi)RNA, long non-coding (lnc)RNA, and circular (circ)RNA in the posttranscriptional regulation of cardiomyocytes. In addition, this review summarizes the roles of ncRNAs in specific species while enumerating potential therapeutic strategies for myocardial infarction.

16.
Opt Express ; 30(5): 6738-6745, 2022 Feb 28.
Artículo en Inglés | MEDLINE | ID: mdl-35299452

RESUMEN

An ultralow-loss silicon planar waveguide crossing operating in the O-band was experimentally demonstrated based on the Gaussian beam synthesis method. Elliptical parabolic inverted tapers were introduced in our design to reduce the crossing loss. According to the measurement results, the proposed device exhibits an insertion loss of 0.008 dB, which is the lowest reported loss for planar silicon waveguide crossings operating in the O-band. The device exhibits a low crosstalk below -40 dB over a 40 nm wavelength range with a compact footprint of 18 × 18 µm2 and can be fabricated in a complementary metal-oxide-semiconductor-compatible process.

17.
Chemosphere ; 297: 134032, 2022 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-35183577

RESUMEN

Intense industrialization has led to the increasing leaching risk of metals into groundwater at heavily polluted industrial sites. However, metal dissolution in polluted industrial soils has been neither fully investigated nor quantified before. In this study, the dissolution of Zn, Ni, and Cu in soil from a heavily contaminated industrial site during a flooding-drainage period was investigated by sequential extraction, geochemical modelling, and X-ray absorption near edge structure spectroscopy. The results showed a steady decrease in metal solubility during both reduction and oxidation stages. During reduction, with limited decrease in Eh (>100 mV), formation of carbonate precipitates rather than sulfide precipitates and adsorption on soil solids was responsible for Zn and Ni dissolution, whereas bound to soil organic matter (SOM) and iron oxides dominated Cu dissolution, due to its lower concentration and higher affinity to SOM and iron oxides compared to Zn and Ni. During oxidation, the acidity caused by ferrous oxidation was buffered by calcite dissolution, while metal precipitation ceased and adsorption on soil surface controlled metal solubility. The metal solubility and speciation during the flooding-drainage process were quantitatively predicted by geochemical model. The findings demonstrate that due to high metal concentrations and weak microbial effect in the industrial soil, metal release was largely regulated by abiotic reactions rather than biotic reactions, which is somehow different from that of the wetland or rice field soils.


Asunto(s)
Metales Pesados , Contaminantes del Suelo , Hierro , Metales/análisis , Metales Pesados/análisis , Óxidos , Suelo , Contaminantes del Suelo/análisis , Solubilidad
18.
J Hazard Mater ; 423(Pt A): 127028, 2022 02 05.
Artículo en Inglés | MEDLINE | ID: mdl-34523500

RESUMEN

Predicting the dynamic behavior of coexisting ions on mineral interface is essential to understanding their lability in soil matrix, but a mechanical kinetic model for predicting competitive adsorption is lacking. In this study, the thermodynamic and kinetic adsorption behaviors of Ni(II), Co(II), Cr(VI), and P(V) on goethite under various condition were investigated by batch and stirred-flow experiments, respectively. The equilibrium model CD-MUSIC was developed to describe their equilibrium behavior, followed by the development of a multi-rate kinetic model constrained by the equilibrium model to describe their kinetic behavior. Ni(II) and Co(II) exhibit similar adsorption affinities, while the adsorption of P(V) was stronger and faster than that of Cr(VI). The two surface species of Cr(VI) and P(V) differed in dynamic features, a finding confirmed by in-situ ATR-FTIR spectroscopy. The kinetic model was successfully used to predict the binary competitive adsorption of Ni(II)-Co(II) and Cr(VI)-P(V), and especially the overshooting of Cr(VI) induced by P(V). Our results showed that an integrated thermodynamic-kinetic model obtained from a single-ion experiment can be extended to describe complex multi-ion interactions, indicating the robustness and scalability of the model's parameters. This approach can be used to construct more comprehensive equilibrium and dynamic models of the actual soil environment.


Asunto(s)
Cromo , Contaminantes Químicos del Agua , Adsorción , Cromo/análisis , Concentración de Iones de Hidrógeno , Compuestos de Hierro , Cinética , Minerales , Contaminantes Químicos del Agua/análisis
19.
Micromachines (Basel) ; 14(1)2022 Dec 27.
Artículo en Inglés | MEDLINE | ID: mdl-36677127

RESUMEN

Edge coupler is a key component of silicon-based optoelectronic chips, which dramatically reduces the coupling loss between fibers and transmission waveguides. Here, we propose an ultralow-loss three-step silicon edge coupler based on a 130 nm CMOS process. By replacing the silicon substrate with a material with a lower refractive index than silicon oxide, the silicon leakage loss and polarization-dependent loss can be significantly improved. This structure avoids the existence of a cantilever, which enhances the mechanical strength of the edge coupler. Coupling with standard single-mode fiber, the simulation results demonstrate that the TE/TM mode has an ultralow loss of 0.63/1.08 dB at 1310 nm and 0.57/1.34 dB at 1550 nm, and the 0.5 dB bandwidth covering the entire communication band is about 400 nm. In the entire communication band, the polarization-dependent loss is less than 0.8 dB. Furthermore, we propose a taper shape design method based on mode analysis, which can be adapted for any taper to improve its compactness. Compared with the parabolic shape, the coupling loss of the edge coupler with a length of 460 µm for the TE mode is improved by 0.3 dB on average, this edge coupler provides a feasible solution for fiber-to-chip coupling and is perfectly suitable for wavelength division multiplexing applications in optical communications.

20.
Front Cardiovasc Med ; 8: 773083, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34869689

RESUMEN

Heart failure (HF) describes a group of manifestations caused by the failure of heart function as a pump that supports blood flow through the body. MicroRNAs (miRNAs), as one type of non-coding RNA molecule, have crucial roles in the etiology of HF. Accordingly, miRNAs related to HF may represent potential novel therapeutic targets. In this review, we first discuss the different roles of miRNAs in the development and diseases of the heart. We then outline commonly used miRNA chemical modifications and delivery systems. Further, we summarize the opportunities and challenges for HF-related miRNA therapeutics targets, and discuss the first clinical trial of an antisense drug (CDR132L) in patients with HF. Finally, we outline current and future challenges and potential new directions for miRNA-based therapeutics for HF.

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