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1.
Spectrochim Acta A Mol Biomol Spectrosc ; 324: 124937, 2025 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-39137709

RESUMO

In this study, the interaction of the human hemoglobin with cost effective and chemically fabricated CdS quantum dots (QDs) (average sizes ≈3nm) has been investigated. The semiconductor QDs showed maximum visible absorption at 445 nm with excitonic formation and band gap of ≈ 2.88 eV along with hexagonal crystalline phase. The binding of QDs-Hb occurs through corona formation to the ground sate complex formation. The life time of the heme pocket binding and reorganization were found to be t1 = 43 min and t2 = 642 min, respectively. The emission quenching of the Hb has been indicated large energy transfer between CdS QDs and Hb with tertiary deformation of Hb. The binding thermodynamics showed highly exothermic nature. The ultrafast decay during corona formation was studied from TCSPC. The results showed that the energy transfer efficiency increases with the increase of the QDs concentration and maximum ≈71.5 % energy transfer occurs and average ultrafast lifetime varies from 5.45 ns to1.51 ns. The deformation and unfolding of the secondary structure of Hb with changes of the α-helix (≈74 % to ≈51.07 %) and ß-sheets (≈8.63 % to ≈10.25 %) have been observed from circular dichroism spectrum. The SAXS spectrum showed that the radius of gyration of CdS QDs-Hb bioconjugate increased (up to 23 ± 0.45 nm) with the increase of the concentration of QDs compare with pure Hb (11 ± 0.23 nm) and Hb becoming more unfolded.


Assuntos
Compostos de Cádmio , Transferência de Energia , Hemoglobinas , Desdobramento de Proteína , Pontos Quânticos , Sulfetos , Pontos Quânticos/química , Humanos , Compostos de Cádmio/química , Sulfetos/química , Sulfetos/metabolismo , Hemoglobinas/química , Hemoglobinas/metabolismo , Ligação Proteica , Termodinâmica , Espectrometria de Fluorescência , Dicroísmo Circular
2.
Sci Rep ; 14(1): 23029, 2024 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-39362945

RESUMO

Slurry retention in fractures decreases after grouting is completed and the pressure supply is stopped, which affects the grouting sealing effect and prevents or restrains the occurrence of such adverse conditions. Based on the time-varying yield stress of grout, a theoretical analysis model of grouting diffusion decay is established, the decay height variation function and the minimum pressure stabilisation time calculation formula are derived, and the sealing mechanism of a jointed rock mass with multiple joints is studied. Moreover, a 3D visualisation laboratory test device for grouting diffusion decay of a jointed rock mass with layers was developed to analyse the diffusion and decay process of grout with different water-cement (W/C) ratios visually, and the correctness of the theoretical model was verified. The results show that: (1) the W/C ratio of grout should not be greater than 2, otherwise it is difficult for grout to remain in the cracks; (2) a large fissure opening easily spreads grout but is not conducive to the retention of grout; and (3) the time of stable pressure determines the retention rate of the slurry in the crack. When the horizontal crack opening width is 3 mm and the W/C ratio of the slurry is 1, the minimum stable pressure time to achieve a better sealing effect is 810 s. The research results can be used to reasonably plan the grouting time and improve the grouting efficiency to ensure the grouting effect, which is crucial for improving the theoretical system of grouting technology.

3.
Elife ; 122024 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-39356734

RESUMO

To function effectively as an integrated system, the transcriptional and post-transcriptional machineries must communicate through mechanisms that are still poorly understood. Here, we focus on the zinc-finger Sfp1, known to regulate transcription of proliferation-related genes. We show that Sfp1 can regulate transcription either by binding to promoters, like most known transcription activators, or by binding to the transcribed regions (gene bodies), probably via RNA polymerase II (Pol II). We further studied the first mode of Sfp1 activity and found that, following promoter binding, Sfp1 binds to gene bodies and affects Pol II configuration, manifested by dissociation or conformational change of its Rpb4 subunit and increased backtracking. Surprisingly, Sfp1 binds to a subset of mRNAs co-transcriptionally and stabilizes them. The interaction between Sfp1 and its client mRNAs is controlled by their respective promoters and coincides with Sfp1's dissociation from chromatin. Intriguingly, Sfp1 dissociation from the chromatin correlates with the extent of the backtracked Pol II. We propose that, following promoter recruitment, Sfp1 accompanies Pol II and regulates backtracking. The backtracked Pol II is more compatible with Sfp1's relocation to the nascent transcripts, whereupon Sfp1 accompanies these mRNAs to the cytoplasm and regulates their stability. Thus, Sfp1's co-transcriptional binding imprints the mRNA fate, serving as a paradigm for the cross-talk between the synthesis and decay of specific mRNAs, and a paradigm for the dual-role of some zinc-finger proteins. The interplay between Sfp1's two modes of transcription regulation remains to be examined.


The ability to fine-tune the production of proteins in a cell is essential for organisms to exist. An imbalance in protein levels can be the cause of various diseases. Messenger RNA molecules (mRNA) link the genetic information encoded in DNA and the produced proteins. Exactly how much protein is made mostly depends on the amount of mRNA in the cell's cytoplasm. This is controlled by two processes: the synthesis of mRNA (also known as transcription) and mRNA being actively degraded. Although much is known about mechanisms regulating transcription and degradation, how cells detect if they need to degrade mRNA based on the levels of its synthesis and vice versa is poorly understood. In 2013, researchers found that proteins known as 'RNA decay factors' responsible for mRNA degradation are actively moved from the cell's cytoplasm into its nucleus to instruct the transcription machinery to produce more mRNA. Kelbert, Jordán-Pla, de-Miguel-Jiménez et al. ­ including some of the researchers involved in the 2013 work ­ investigated how mRNA synthesis and degradation are coordinated to ensure a proper mRNA level. The researchers used advanced genome engineering methods to carefully manipulate and measure mRNA production and degradation in yeast cells. The experiments revealed that the protein Sfp1 ­ a well-characterized transcription factor for stimulating the synthesis of a specific class of mRNAs inside the nucleus ­ can also prevent the degradation of these mRNAs outside the nucleus. During transcription, Sfp1 bound directly to mRNA. The investigators could manipulate the co-transcriptional binding of Sfp1 to a certain mRNA, thereby changing the mRNA stability in the cytoplasm. This suggests that the ability of Sfp1 to regulate both the production and decay of mRNA is dependent on one another and that transcription can influence the fate of its transcripts. This combined activity can rapidly change mRNA levels in response to changes in the cell's environment. RNA plays a key role in ensuring correct levels of proteins. It can also function as an RNA molecule, independently of its coding capacity. Many cancers and developmental disorders are known to be caused by faulty interactions between transcription factors and nucleic acids. The finding that some transcription factors can directly regulate both mRNA synthesis and its destruction introduces new angles for studying and understanding these diseases.


Assuntos
RNA Polimerase II , RNA Mensageiro , Fatores de Transcrição , RNA Mensageiro/metabolismo , RNA Mensageiro/genética , RNA Polimerase II/metabolismo , RNA Polimerase II/genética , Fatores de Transcrição/metabolismo , Fatores de Transcrição/genética , Estabilidade de RNA , Regiões Promotoras Genéticas , Ligação Proteica , Dedos de Zinco , Transcrição Gênica , Proteínas de Ligação a DNA/metabolismo , Proteínas de Ligação a DNA/genética , Citoplasma/metabolismo , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae
4.
J Integr Plant Biol ; 2024 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-39360899

RESUMO

Disease resistance is often associated with compromised plant growth and yield due to defense-growth tradeoffs. However, key components and mechanisms underlying the defense-growth tradeoffs are rarely explored in maize. In this study, we find that ZmSKI3, a putative subunit of the SUPERKILLER (SKI) complex that mediates the 3'-5' degradation of RNA, regulates both plant development and disease resistance in maize. The Zmski3 mutants showed retarded plant growth and constitutively activated defense responses, while the ZmSKI3 overexpression lines are more susceptible to Curvularia lunata and Bipolaris maydis. Consistently, the expression of defense-related genes was generally up-regulated, while expressions of growth-related genes were mostly down-regulated in leaves of the Zmski3-1 mutant compared to that of wild type. In addition, 223 differentially expressed genes that are up-regulated in Zmski3-1 mutant but down-regulated in the ZmSKI3 overexpression line are identified as potential target genes of ZmSKI3. Moreover, small interfering RNAs targeting the transcripts of the defense- and growth-related genes are differentially accumulated, likely to combat the increase of defense-related transcripts but decrease of growth-related transcripts in Zmski3-1 mutant. Taken together, our study indicates that plant growth and immunity could be regulated by both ZmSKI3-mediated RNA decay and post-transcriptional gene silencing in maize.

5.
J Magn Reson ; 368: 107762, 2024 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-39299053

RESUMO

In the case of limited sampling windows or truncation of free induction decays (FIDs) for artifact removal in proton magnetic resonance spectroscopy (1H-MRS) and spectroscopic imaging (1H-MRSI), metabolite quantification needs to be performed on incomplete FIDs. Given that FIDs are naturally time-domain sequential data, we investigated the potential of recurrent neural network (RNN)-types of neural networks (NNs) in the processing of incomplete human brain FIDs with or without FID restoration prior to quantitative analysis at 3.0T. First, we employed an RNN encoder-decoder and developed it to restore incomplete FIDs (rRNN) with different amounts of sampled data. The quantification of metabolites from the rRNN-restored FIDs was achieved by using LCModel. Second, we modified the RNN encoder-decoder and developed it to convert incomplete brain FIDs into incomplete metabolite-only FIDs without restoration, followed by linear regression using a metabolite basis set for quantitative analysis (cRNN). In consideration of the practical benefit of the FID restoration with respect to pure zero-filling, development and analysis of the NNs were focused particularly on the incomplete FIDs with only the first 64 data points retained. All NNs were trained on simulated data and tested mainly on in vivo data acquired from healthy volunteers (n = 27). Strong correlations were obtained between the NN-derived and ground truth metabolite content (LCModel-derived content on fully sampled FIDs) for myo-inositol, total choline, and total creatine (normalized to total N-acetylaspartate) on the in vivo data using both rRNN (R = 0.83-0.94; p ≤ 0.05) and cRNN (R = 0.86-0.91; p ≤ 0.05). RNN-types of NNs have potential in the quantification of the major brain metabolites from the FIDs with substantially reduced sampled data points. For the metabolites with low to medium SNR, the performance of the NNs needs to be further improved, for which development of more elaborate and advanced simulation techniques would be of help, but remains challenging.

6.
Artigo em Inglês | MEDLINE | ID: mdl-39340290

RESUMO

Background: The rate of disease progression, measured by the decline of ALS Functional Rating Scale-Revised (ALSFRS-R) from symptom onset to diagnosis (ΔFS) is a well-established prognostic biomarker for predicting survival. Objectives: This study aims to categorize a large patient cohort based on the initial ΔFS and subsequently investigate survival deviations from the expected prognosis defined by ΔFS. Methods: 1056 ALS patients were stratified into three progression categories based on their ΔFS: slow progressors (below 25th percentile), intermediate progressors (between 25th and 75th percentiles), and fast progressors (above 75th percentile). Survival outcomes were classified as short survivors (<2 years), average survivors (2-5 years), and long survivors (>5 years). Clinical and demographic characteristics within each subgroup were then analyzed. Results: ΔFS stratification yielded cutoff values of <0.29, 0.29-1.03, and >1.03 points/month. Long survivors comprised 26% and 21% were short survivors. Six percent of the fast progressors had a life expectancy of more than 5 years, and none of the clinical and demographic characteristics analyzed could fully explain this discrepancy. Conversely, 13% of intermediate progressors lived less than 2 years, according to a short-diagnostic delay in these patients. Discussion: Our study reaffirms ΔFS as a prognostic biomarker for ALS. We disclosed outliers defying anticipated patterns. The observed shift in progression categories underscores the non-linear nature of disease progression. Genetic and unknown biological reasons may explain these deviations. Further research is needed to fully understand modulation of ALS survival.

7.
Cell Rep ; 43(10): 114781, 2024 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-39331503

RESUMO

Animal development is dictated by the selective and timely decay of mRNAs in developmental transitions, but the impact of mRNA decapping scaffold proteins in development is unclear. This study unveils the roles and interactions of the DCAP-2 decapping scaffolds EDC-3 and EDC-4 in the embryonic development of C. elegans. EDC-3 facilitates the timely removal of specific embryonic mRNAs, including cgh-1, car-1, and ifet-1 by reducing their expression and preventing excessive accumulation of DCAP-2 condensates in somatic cells. We further uncover a role for EDC-3 in defining the boundaries between P bodies, germ granules, and stress granules. Finally, we show that EDC-4 counteracts EDC-3 and engenders the assembly of DCAP-2 with the GID (CTLH) complex, a ubiquitin ligase involved in maternal-to-zygotic transition (MZT). Our findings support a model where multiple RNA decay mechanisms temporally clear maternal and zygotic mRNAs throughout embryonic development.

8.
Sci Total Environ ; 953: 176251, 2024 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-39277004

RESUMO

High coastal nutrient loading can cause changes in seagrass chemistry traits that may lead to variability in seagrass litter decomposition processes. Such changes in decomposition have the potential to alter the carbon (C) sequestration capacity within seagrass meadows ('blue carbon'). However, the external and internal factors that drive the variability in decomposition rates of the different organic matter (OM) types of seagrass are poorly understood, especially recalcitrant OM (i.e. cellulose-associated OM and lignin-associated OM), thereby limiting our ability to evaluate the C sequestration potential. It was conducted a laboratory incubation to compare differences in the decomposition of Halophila beccarii litter collected from seagrass meadows with contrasting nutrient loading histories. The exponential decay constants of seagrass litter mass, cellulose-associated OM and lignin-associated OM were 0.009-0.032, 0.014-0.054 and 0.009-0.033 d-1, respectively. The seagrass litter collected from meadows with high nutrient loading exhibited greater losses of mass (25.0-41.2 %), cellulose-associated OM (2.8-18.5 %) and lignin-associated OM (9.6-31.2 %) than litter from relatively low nutrient loading meadows. The initial and temporal changes of the litter nitrogen (N) and phosphorus (P) concentrations, stoichiometric ratios of lignin/N, C/N, and C/P, and cellulose-associated OM content, were strongly correlated with the losses of litter mass and different types of OM. Further, temporal changes of litter C and OM types, particularly the OM and labile OM concentrations, were identified as the main driving factors for the loss of litter mass and loss of different OM types. These results indicated that nutrient-loaded seagrass litter, characterized by elevated nutrient levels and diminished amounts of recalcitrant OM, exhibits an accelerated decay rate for the recalcitrant OM. These differences in litter quality would lead to a reduced contribution of seagrass litter to long-term C stocks in eutrophic meadows, thereby weakening the stability of C sequestration. Considering the expected changes in seagrass litter chemistry traits and decay rates due to long-term nutrient loading, this study provides useful information for improving C sequestration capabilities through effective pollution management.


Assuntos
Sequestro de Carbono , Nutrientes/análise , Hydrocharitaceae , Nitrogênio/análise , Lignina , Fósforo/análise , Carbono , Biodegradação Ambiental
9.
Genes (Basel) ; 15(9)2024 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-39336755

RESUMO

Previous research has highlighted significant phenotypic discrepancies between knockout and knockdown approaches in zebrafish, raising concerns about the reliability of these methods. However, our study suggests that these differences are not as pronounced as was once believed. By carefully examining the roles of maternal and zygotic gene contributions, we demonstrate that these factors significantly influence phenotypic outcomes, often accounting for the observed discrepancies. Our findings emphasize that morpholinos, despite their potential off-target effects, can be effective tools when used with rigorous controls. We introduce the concept of graded maternal contribution, which explains how the uneven distribution of maternal mRNA and proteins during gametogenesis impacts phenotypic variability. Our research categorizes genes into three types-susceptible, immune, and "Schrödinger" (conditional)-based on their phenotypic expression and interaction with genetic compensation mechanisms. This distinction provides new insights into the paradoxical outcomes observed in genetic studies. Ultimately, our work underscores the importance of considering both maternal and zygotic contributions, alongside rigorous experimental controls, to accurately interpret gene function and the mechanisms underlying disease. This study advocates for the continued use of morpholinos in conjunction with advanced genetic tools like CRISPR/Cas9, stressing the need for a meticulous experimental design to optimize the utility of zebrafish in genetic research and therapeutic development.


Assuntos
Técnicas de Silenciamento de Genes , Fenótipo , Peixe-Zebra , Peixe-Zebra/genética , Peixe-Zebra/imunologia , Animais , Morfolinos/genética , Técnicas de Inativação de Genes , Proteínas de Peixe-Zebra/genética , Sistemas CRISPR-Cas , Zigoto/metabolismo , Feminino
10.
J Ultrasound Med ; 2024 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-39308358

RESUMO

OBJECTIVES: Skeletal muscle wasting is a common occurrence in critical illness, often resulting in intensive care unit (ICU)-acquired weakness. This study aims to identify clinical factors associated with muscle decay in mechanically ventilated critically ill children. Utilizing point-of-care ultrasound, a noninvasive and cost-effective tool, we assess muscle decay through ultrasound of the quadriceps femoris. METHODS: A prospective observational study was conducted in a single-center quaternary-care pediatric intensive care unit at a children's hospital. A convenience sample of 103 sedated and mechanically ventilated patients were enrolled in this study. Ultrasound measurements of quadriceps femoris muscle thickness were taken, and daily muscle decay rates were calculated. Demographic, clinical, and outcome data were analyzed for correlations with muscle decay. RESULTS: Among the enrolled patients, 67 had repeat measurements. Muscle thickness change aligned with prior studies, with a mean daily change of -1.9% [IQR -0.8, -5.0]. Adequate cumulative caloric intake (>60% of goal) correlated with less muscle decay compared with inadequate intake (-1.8 vs -2.4%, P < .001). Average daily muscle change correlated with both ICU and hospital length of stay (LOS) (r = .328, P = .007 and r = .393, P = .001). No significant correlations emerged between muscle change and mortality, disease severity, fluid balance, early mobilization, steroid exposure, or sedative and paralytic use. CONCLUSION: This study demonstrates early and frequent muscle decay in critically ill children, as detected by point-of-care ultrasound. Average daily muscle decay was associated with longer ICU and hospital LOS. Adequate cumulative caloric intake is linked to reduced muscle decay. These findings contribute to understanding muscle wasting in critically ill pediatric patients.

11.
Sci Rep ; 14(1): 21909, 2024 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-39300160

RESUMO

This study aims to analyze the vibration signals near the ground surface due to the underneath drilling and blasting activities in a fissured rock tunnel. Blasting induced vibration on the ground surface was continuously monitored in a fissured rock tunnel drilling and blasting excavation project in field. Wavelet packet analysis of the vibration signals using Matlab was carried out for signal denoising, differential blasting delay time interval identification, and three-way time-frequency energy analysis. The results show that within a 30 m range from the palm face, the dominant frequency bands of blasting-induced vibrations on the ground surface were concentrated in the range of 0-130 Hz. Two prominent peak frequency bands were identified at 31.25-39.063 Hz (low-frequency band) and 93.75-101.56 Hz (high-frequency band), accounting for 12% of the total energy. Among the three directions of ground surface vibrations, the energy decay was the most significant in the x-direction (tunnel excavation direction), which amounted to 54.29% of the overall energy decay with increasing distance. The energy decay within the 50-80 Hz range was the most pronounced (more than 90%), when the angle between the vibration propagation direction and the fissure or joint direction was 75°. The conclusions provide the insights in the attenuation of blast-induced vibrations in fissured rock and can potentially assist in the design of blasting vibration control.

12.
G3 (Bethesda) ; 2024 09 13.
Artigo em Inglês | MEDLINE | ID: mdl-39271111

RESUMO

The modified E. coli biotin ligase BirA* was the first developed for proximity labeling of proteins (BioID). However, it has low activity at temperatures below 37˚C, which reduces its effectiveness in organisms growing at lower temperatures, such as budding yeast. Multiple derivatives of the enzymes have been engineered, but a thorough comparison of these variations of biotin ligases and the development of versatile tools for conducting these experiments in Saccharomyces cerevisiae would benefit the community. Here, we designed a suite of vectors to compare the activities of biotin ligase enzymes in yeast. We found that the newer TurboID versions were the most effective at labeling proteins, but they displayed low constitutive labeling of proteins even in the absence of exogenous biotin, due to biotin contained in the culture medium. We describe a simple strategy to express free BioID enzymes in cells that can be used as an appropriate control in BioID studies to account for the promiscuous labeling of proteins caused by random interactions between bait-BioID enzymes in cells. We also describe chemically-induced BioID systems exploiting the rapamycin-stabilized FRB-FKBP interaction. Finally, we used the TurboID version of the enzyme to explore the interactome of different subunits of the Ccr4-Not gene regulatory complex. We find that Ccr4-Not predominantly labeled cytoplasmic mRNA regulators, consistent with its function in mRNA decay and translation quality control in this cell compartment.

13.
J Anim Ecol ; 93(10): 1582-1592, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39252414

RESUMO

Understanding spatial variation in species distribution and community structure is at the core of community ecology. Nevertheless, the effect of distance on metacommunity structure remains little studied. We examine how plant-pollinator community structure changes across geographical distances at a regional scale and disentangle its underlying local and regional processes. We use a multilayer network to represent linked plant-pollinator communities as a metacommunity in the Canary Islands. We used modularity (i.e. the extent to which the community is partitioned into groups of densely interacting species) to quantify distance decay in structure across space. In multilayer modularity, the same species can belong to different modules in different communities, and modules can span communities. This enabled quantifying how similarity in module composition varied with distance between islands. We developed three null models, each controlling for a separate component of the multilayer network, to disentangle the role of species turnover, interaction rewiring and local factors in driving distance decay in structure. We found a pattern of distance decay in structure, indicating that islands tended to share fewer modules with increasing distance. Species turnover (but not interaction rewiring) was the primary regional process triggering distance decay in structure. Local interaction structure also played an essential role in determining the structure similarity of communities at a regional scale. Therefore, local factors that determine species interactions occurring at a local scale drive distance decay in structure at a regional scale. Our work highlights the interplay between local and regional processes underlying community structure. The methodology, and specifically the null models, we developed provides a general framework for linking communities in space and testing different hypotheses regarding the factors generating spatial structure.


Assuntos
Polinização , Animais , Espanha , Modelos Biológicos , Insetos/fisiologia , Ecossistema
14.
Small Methods ; : e2401206, 2024 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-39344151

RESUMO

High-capacity O3-type lithium-rich manganese-based (LRM) materials exhibit significant structural instability and severe voltage decay, which limit their practical applications. In contrast, the O2-type LRM materials demonstrate remarkable structural stability despite offering lower capacity. In this study, a composite material, O3@O2-LRM is designed, by coating the main structure of O3-type LRM with a minor amount of O2-type LRM to combine the high capacity of the O3 phase with the superior stability of the O2 phase. Electrochemical tests demonstrate that O3@O2-LRM exhibits both high specific capacity and reduced voltage decay. Furthermore, a series of characterizations after different cycles confirm its enhanced structure stability compared to O3-LRM. This novel structure holds great promise for developing advanced cathode materials capable of meeting the demanding requirements of next-generation Li-ion batteries.

15.
Small ; : e2407124, 2024 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-39344554

RESUMO

Microporous carbon confined nano silicon composites (Si/m-C) are considered to be the best anode materials for high-energy-density lithium-ion batteries compared with the other Si-based materials such as SiO, due to high initial Coulombic efficiency (ICE) and capacity, as well as good cycling stability. However, there is a lack of multilevel comprehensive evaluation of Si/m-C, which poses potential risks to the commercial application. Herein, combined with quantitative titration, mechanical characterization, and bulk/interface evolution analysis, a systematic evolution of commercialized Si/m-C from the particle level to the cylindrical cell level is conducted, revealing the decay mechanism and proposing corresponding solutions. Among them, it is well demonstrated that the Si/m-C still withstands huge volume expansion of over 200% with poor mechanical strength, causing the electrical contact loss of active LixSi and severe interfacial side reactions. Moreover, even blending more than 90% graphite cannot completely suppress its volumetric strain, and the combination of highly flexible single-walled carbon nanotubes (SWCNT) is necessary. In response to this, the 32700-type cylindrical cell with a designed capacity of 9.5 Ah is assembled by mixing Si/m-C with 90% graphite and SWCNT as anode, achieving a long-term cycling stability over 300 cycles at 0.5 C with a capacity retention of 94.8%.

16.
Comput Biol Chem ; 113: 108223, 2024 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-39340962

RESUMO

BACKGROUND AND OBJECTIVE: The reconstruction of gene regulatory networks (GRNs) stands as a vital approach in deciphering complex biological processes. The application of nonlinear ordinary differential equations (ODEs) models has demonstrated considerable efficacy in predicting GRNs. Notably, the decay rate and time delay are pivotal in authentic gene regulation, yet their systematic determination in ODEs models remains underexplored. The development of a comprehensive optimization framework for the effective estimation of these key parameters is essential for accurate GRN inference. METHOD: This study introduces GRNMOPT, an innovative methodology for inferring GRNs from time-series and steady-state data. GRNMOPT employs a combined use of decay rate and time delay in constructing ODEs models to authentically represent gene regulatory processes. It incorporates a multi-objective optimization approach, optimizing decay rate and time delay concurrently to derive Pareto optimal sets for these factors, thereby maximizing accuracy metrics such as AUROC (Area Under the Receiver Operating Characteristic curve) and AUPR (Area Under the Precision-Recall curve). Additionally, the use of XGBoost for calculating feature importance aids in identifying potential regulatory gene links. RESULTS: Comprehensive experimental evaluations on two simulated datasets from DREAM4 and three real gene expression datasets (Yeast, In vivo Reverse-engineering and Modeling Assessment [IRMA], and Escherichia coli [E. coli]) reveal that GRNMOPT performs commendably across varying network scales. Furthermore, cross-validation experiments substantiate the robustness of GRNMOPT. CONCLUSION: We propose a novel approach called GRNMOPT to infer GRNs based on a multi-objective optimization framework, which effectively improves inference accuracy and provides a powerful tool for GRNs inference.

17.
J Food Sci ; 89(10): 6616-6627, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39230384

RESUMO

This study investigated the potential use of curcumin-mediated photodynamic treatment as a postharvest decontamination technique to reduce microbial load and growth and therefore extend the shelf life of strawberries. Curcumin was applied on strawberries, followed by illumination and storage at 4°C for 16 days. Strawberries were evaluated for decay, microbial load, and physicochemical properties such as weight loss, color, and firmness during storage. The findings revealed that curcumin-mediated photodynamic treatment effectively reduced the decay incidence and severity in strawberries, with 20% less decay occurrence compared to untreated fruits, which was shown to be dependent on curcumin concentration. While a complete reduction in microbial load was observed upon treatment, microbial growth remained unaffected throughout storage. Moreover, photodynamic treatment did not show any adverse impact on color properties and firmness of strawberries. This eco-friendly technique presents potential for fruit's shelf-life extension, although optimization of treatment parameters and photodynamic unit design seems to be essential.


Assuntos
Curcumina , Conservação de Alimentos , Armazenamento de Alimentos , Fragaria , Frutas , Fragaria/microbiologia , Curcumina/farmacologia , Armazenamento de Alimentos/métodos , Frutas/microbiologia , Frutas/química , Conservação de Alimentos/métodos , Cor
18.
Angew Chem Int Ed Engl ; : e202412483, 2024 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-39218804

RESUMO

Purely organic molecules exhibiting near-infrared (NIR) emission possess considerable potential for applications in both biological and optoelectronic technological domains, owing to their inherent advantages such as cost-effectiveness, biocompatibility, and facile chemical modifiability. However, the repertoire of such molecules with emission peaks exceeding 750 nm and concurrently demonstrating high photoluminescence quantum efficiency (PLQE) remains relatively scarce due to the energy gap law. Herein, we report two open-shell NIR radical emitters, denoted as DMNA-Cz-BTM and DMNA-PyID-BTM, achieved through the strategic integration of a donor group (DMNA) onto the Cz-BTM and PyID-BTM frameworks, respectively. We found that the donor-acceptor molecular structure allows the two designed radical emitters to exhibit a charge-transfer excited state and spatially separated electron and hole levels with non-bonding characteristics. Thus, the high-frequency vibrations are effectively suppressed. Besides, the reduction of low-frequency vibrations is observed. Collectively, the non-radiative decay channel is significantly suppressed, leading to exceptional NIR PLQE values. Specifically, DMNA-Cz-BTM manifests an emission peak at 758 nm alongside a PLQE of 55%, whereas DMNA-PyID-BTM exhibits an emission peak at 778 nm with a PLQE of 66%. Notably, these represent the pinnacle of PLQE among metal-free organic NIR emitters with emission peaks surpassing 750 nm.

19.
J Fish Biol ; 2024 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-39225310

RESUMO

The degradation of environmental DNA (eDNA) and its release from fish were investigated in laboratory experiments for seven salmonid fishes. The eDNA concentration in experimental tanks without fish decreased exponentially, with a higher rate of decline observed under higher water temperature conditions. When a fish was introduced into a tank, the eDNA concentration was positively correlated with the length and weight of the fish.

20.
J Public Health Dent ; 2024 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-39253777

RESUMO

OBJECTIVE: Individuals with disabilities face elevated risks of adverse oral health outcomes compared with the general population, including worse periodontal health, increased edentulism, and untreated dental decay. Given the varied impacts of different disabilities on people's health and well-being, this study aims to investigate diverse associations between untreated decay and cognitive, physical, emotional, and sensory disabilities among US adults. METHODS: This cross-sectional study analyzed questionnaire and clinical examination data on 7084 adults (≥20 years) from the 2015-18 National Health and Nutrition Examination Survey cycles. Sociodemographics, oral health behaviors, health conditions, and disability were all examined. The prevalence of tooth decay was calculated as the proportion of adults with untreated decay. Survey-weighted multivariable logistic regression was used to assess associations between disability and untreated decay. RESULTS: In general, untreated decay was more than twice as prevalent in individuals with three or more disabilities as in those without any disabilities (34.5% vs. 13.2%, p < 0.001). After adjusting for confounders, lack of functional dentition was the most significant predictor of untreated decay prevalence (adjusted odds ratio: 2.97, 95% CI: 2.37-3.72). Other significant factors were younger age (20-44), non-Hispanic black race or ethnicity, low-income status, having an underlying chronic condition, not having a past-year dental visit, symptomatic dental visits, and current tobacco use. CONCLUSION: No associations were found between disability type (cognitive, emotional, physical, and sensory) and untreated decay among community-dwelling US adults. Several health-related, social, and behavioral factors emerged as primary predictors of untreated decay. Further research is needed to explore disability types and dental caries determinants.

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