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1.
BMC Pregnancy Childbirth ; 24(1): 236, 2024 Apr 04.
Article in English | MEDLINE | ID: mdl-38575874

ABSTRACT

BACKGROUND: To analyze the impact of the time of natural cessation of the umbilical cord on maternal and infant outcomes in order to explore the time of clamping that would be beneficial to maternal and infant outcomes. METHODS: The study was a cohort study and pregnant women who met the inclusion and exclusion criteria at the Obstetrics and Gynecology Department of Qilu Hospital of Shandong University from September 2020 to September 2021. Analysis using Kruskal-Wallis rank sum test, Pearson's Chi-squared test, generalized linear mixed model (GLMM) and repeated measures ANOVA. If the difference between groups was statistically significant, the Bonferroni test was then performed. A two-sided test of P < 0.05 was considered statistically significant. RESULTS: A total of 345 pregnants were included in this study. The subjects were divided into the ≤60 seconds group (n = 134), the 61-89 seconds group (n = 106) and the ≥90 seconds group (n = 105) according to the time of natural arrest of the umbilical cord. There was no statistically significant difference in the amount of postpartum hemorrhage and the need for iron, medication, or supplements in the postpartum period between the different cord spontaneous arrest time groups for mothers (P > 0.05). The weight of the newborns in the three groups was (3316.27 ± 356.70) g, (3387.26 ± 379.20) g, and (3455.52 ± 363.78) g, respectively, and the number of days of cord detachment was 12.00 (8.00, 15.75) days, 10.00 (7.00, 15.00) days and 9.00 (7.00, 13.00) days, respectively, as the time of natural cessation of the cord increased. The neonatal lymphocyte ratio, erythrocyte pressure, and hemoglobin reached a maximum in the 61-89 s group at (7.41 ± 2.16) %, (61.77 ± 8.17) % and (194.52 ± 25.84) g/L, respectively. Lower incidence of neonatal hyperbilirubinemia in the 61-89 s group compared to the ≥90s group 0 vs 4.8 (P < 0.05). CONCLUSIONS: In full-term singleton vaginal births, maternal and infant outcomes are better when waiting for 61-89 s after birth for the cord to stop pulsating naturally, suggesting that we can wait up to 90s for the cord to stop pulsating naturally, and if the cord does not stop pulsating after 90s, artificial weaning may be more beneficial to maternal and infant outcomes.


Subject(s)
Postpartum Hemorrhage , Umbilical Cord , Infant , Infant, Newborn , Pregnancy , Humans , Female , Cohort Studies , Prospective Studies , Term Birth
2.
New Phytol ; 241(2): 687-702, 2024 Jan.
Article in English | MEDLINE | ID: mdl-37950543

ABSTRACT

Hypocotyl elongation is controlled by several signals and is a major characteristic of plants growing in darkness or under warm temperature. While already several molecular mechanisms associated with this process are known, protein degradation and associated E3 ligases have hardly been studied in the context of warm temperature. In a time-course phosphoproteome analysis on Arabidopsis seedlings exposed to control or warm ambient temperature, we observed reduced levels of diverse proteins over time, which could be due to transcription, translation, and/or degradation. In addition, we observed differential phosphorylation of the LRR F-box protein SLOMO MOTION (SLOMO) at two serine residues. We demonstrate that SLOMO is a negative regulator of hypocotyl growth, also under warm temperature conditions, and protein-protein interaction studies revealed possible interactors of SLOMO, such as MKK5, DWF1, and NCED4. We identified DWF1 as a likely SLOMO substrate and a regulator of warm temperature-mediated hypocotyl growth. We propose that warm temperature-mediated regulation of SLOMO activity controls the abundance of hypocotyl growth regulators, such as DWF1, through ubiquitin-mediated degradation.


Subject(s)
Arabidopsis Proteins , Arabidopsis , F-Box Proteins , Arabidopsis/metabolism , Hypocotyl/metabolism , Arabidopsis Proteins/metabolism , Temperature , F-Box Proteins/metabolism , Gene Expression Regulation, Plant
3.
IEEE Trans Image Process ; 33: 382-394, 2024.
Article in English | MEDLINE | ID: mdl-38127610

ABSTRACT

Image outpainting gains increasing attention since it can generate the complete scene from a partial view, providing a valuable solution to construct 360° panoramic images. As image outpainting suffers from the intrinsic issue of unidirectional completion flow, previous methods convert the original problem into inpainting, which allows a bidirectional flow. However, we find that inpainting has its own limitations and is inferior to outpainting in certain situations. The question of how they may be combined for the best of both has as yet remained under-explored. In this paper, we provide a deep analysis of the differences between inpainting and outpainting, which essentially depends on how the source pixels contribute to the unknown regions under different spatial arrangements. Motivated by this analysis, we present a Cylin-Painting framework that involves meaningful collaborations between inpainting and outpainting and efficiently fuses the different arrangements, with a view to leveraging their complementary benefits on a seamless cylinder. Nevertheless, straightforwardly applying the cylinder-style convolution often generates visually unpleasing results as it discards important positional information. To address this issue, we further present a learnable positional embedding strategy to incorporate the missing component of positional encoding into the cylinder convolution, which significantly improves the panoramic results. It is noted that while developed for image outpainting, the proposed algorithm can be effectively extended to other panoramic vision tasks, such as object detection, depth estimation, and image super-resolution. Code will be made available at https://github.com/KangLiao929/Cylin-Painting.

4.
J Chem Phys ; 159(22)2023 Dec 14.
Article in English | MEDLINE | ID: mdl-38088431

ABSTRACT

We formulate a contraction theorem that maps quantum dynamics of a multilevel degenerate system (DS) driven by a time-dependent external field to the dynamics of the corresponding contracted non-degenerate system (CNS) of lower dimension, provided transitions between each pair of degenerate levels in the DS have identical transition dipole moments. The theorem is valid for an external field of any strength and shape, with and without rotating wave approximation in the system-field interaction. It establishes explicit relations between DS and CNS observables, significantly simplifies numerical calculations, and clarifies physical origins of the field-induced DS dynamics.

5.
Article in English | MEDLINE | ID: mdl-38090834

ABSTRACT

Existing Transformers for monocular 3D human shape and pose estimation typically have a quadratic computation and memory complexity with respect to the feature length, which hinders the exploitation of fine-grained information in high-resolution features that is beneficial for accurate reconstruction. In this work, we propose an SMPL-based Transformer framework (SMPLer) to address this issue. SMPLer incorporates two key ingredients: a decoupled attention operation and an SMPL-based target representation, which allow effective utilization of high-resolution features in the Transformer. In addition, based on these two designs, we also introduce several novel modules including a multi-scale attention and a joint-aware attention to further boost the reconstruction performance. Extensive experiments demonstrate the effectiveness of SMPLer against existing 3D human shape and pose estimation methods both quantitatively and qualitatively. Notably, the proposed algorithm achieves an MPJPE of 45.2 mm on the Human3.6M dataset, improving upon the state-of-the-art approach [1] by more than 10% with fewer than one-third of the parameters.

6.
Front Cardiovasc Med ; 10: 1277427, 2023.
Article in English | MEDLINE | ID: mdl-38149265

ABSTRACT

Background: To investigate the correlation between lg (circSCMH1/miR-874) and acute coronary syndrome (ACS), acute myocardial infarction (AMI), and carotid plaque stability. Methods: 701 patients were divided into stable coronary artery disease (SCAD), ACS, and control groups. Furthermore, 225 patients who underwent carotid ultrasound were selected from the above 701 patients and were divided into low-risk plaque, medium-to-high risk plaque, and control (without carotid plaques) groups. We collected their baseline characteristics and measured the contents of exosomal circSCMH1 and miR-874 in peripheral blood. Then lg(circSCMH1/miR-874) was calculated and statistical analysis was performed. Results: The lg (circSCMH1/miR-874) values of ACS, SCAD, and the control group decreased successively (P < 0.05). Compared with the low-risk plaque and control groups, the lg (circSCMH1/miR-874) value of medium-high risk plaque group decreased (P < 0.05). Multivariate logistic regression analysis showed that with the decrease of lg (circSCMH1/miR-874), the risk of ACS, AMI, and medium-high risk plaques increased. ROC curve analysis demonstrated that lg (circSCMH1/miR-874) has a higher diagnostic value for ACS, AMI and medium-high risk plaques than previously used predictive ratios. Conclusion: Lg (circSCMH1/miR-874) is closely associated with coronary and carotid plaque stability.

7.
Front Chem ; 11: 1273388, 2023.
Article in English | MEDLINE | ID: mdl-37927561

ABSTRACT

Introduction: Three different shapes of gold nanoparticles were synthesized in this experiment. At the same time, studies compared their effects with human serum albumin (HSA). Methods: Gold nanoparticles (AuNPs) with three different morphologies, such as, nanospheres (AuNSs), nanorods (AuNRs), and nanoflowers (AuNFs) were synthesized via a seeding method and their characteristic absorption peaks were detected using ultraviolet-visible (UV-vis) absorption spectroscopy, Telectron microscopy (TEM), Dynamic Light Scattering (DLS) and Zeta potential measurements, circular dichroism (CD), and Fourier transform infrared spectroscopy (FTIR) to study the interactions between them and HSA. By comparing the thermodynamic parameters and quenching mechanism of the three materials, similarities and differences were determined in their interactions with HSA. Results: The results showed that with an increase in the concentration of the AuNPs with the three different morphologies, the UV-vis absorption peak intensity of the mixed solution increased, but its fluorescence intensity was quenched. This indicates that the three types of AuNPs interact with HSA, and that the interactions between them represent a static quenching process, which is consistent with the conclusions derived from three-dimensional fluorescence experiments. Through variable-temperature fluorescence experiments, the binding constants, number of binding sites, and thermodynamic parameters of the interactions between the three types of AuNPs and HSA were determined. The Gibbs free energy changes were <0, indicating that the reactions of the three types of AuNPs with HSA are spontaneous, resulting in associated matter. Binding constant measurements indicated that the strongest binding took place between the AuNFs and HSA. In addition, the results of fluorescence, CD spectroscopy, and FTIR showed that three different shapes of AuNPs can induce conformational changes in HSA and reduce the α-helix content. Among them, AuNFs have the smallest ability to induce conformational changes. Discussion: According to studies, AuNFs interact more favorably with HSA. This can be used as a reference for the administration of drugs containing AuNPs.

8.
Bioengineered ; 14(1): 2274150, 2023 12.
Article in English | MEDLINE | ID: mdl-37927226

ABSTRACT

Transplantation of tissue-engineered trachea is an effective treatment for long-segment tracheal injury. This technology avoids problems associated with a lack of donor resources and immune rejection, generating an artificial trachea with good biocompatibility. To our knowledge, a systematic summary of basic and clinical research on tissue-engineered trachea in the last 20 years has not been conducted. Here, we analyzed the development trends of tissue-engineered trachea research by bibliometric means and outlined the future perspectives in this field. The Web of Science portal was selected as the data source. CiteSpace, VOSviewer, and the Bibliometric Online Analysis Platform were used to analyze the number of publications, journals, countries, institutions, authors, and keywords from 475 screened studies. Between 2000 and 2023, the number of published studies on tissue-engineered trachea has been increasing. Biomaterials published the largest number of papers. The United States and China have made the largest contributions to this field. University College London published the highest number of studies, and the most productive researcher was an Italian scholar, Paolo Macchiarini. However, close collaborations between various researchers and institutions from different countries were generally lacking. Despite this, keyword analysis showed that manufacturing methods for tracheal stents, hydrogel materials, and 3D bioprinting technology are current popular research topics. Our bibliometric study will help scientists in this field gain an in-depth understanding of the current research progress and development trends to guide their future work, and researchers in related fields will benefit from the introduction to transplantation methods of tissue-engineered trachea.


We conducted a comprehensive bibliometric analysis of tissue-engineered trachea.We systematically outlined the preparation methods and current development forms of tissue-engineered trachea.We predicted future tissue-engineered trachea research trends from the perspectives of countries, institutions, researchers, and popular research topics.


Subject(s)
Tissue Engineering , Trachea , Humans , Trachea/surgery , Bibliometrics , Biocompatible Materials , China
9.
Horm Metab Res ; 55(12): 835-845, 2023 Dec.
Article in English | MEDLINE | ID: mdl-37793427

ABSTRACT

Resistin, a diminutive secretory adipokine, has been linked to obesity and its related ailments. A growing body of evidence suggests that resistin may also be related to the pathogenesis preeclampsia. However, results of previous studies were not consistent. We performed a systematic review and meta-analysis to evaluate the level of circulating resistin in women with PE. A systematic search of Medline, Web of Science, and Embase databases from inception to April 28, 2023, was conducted to identify studies that compared blood resistin levels in pregnant women with and without PE. A random-effects model was utilized to pool the results, accounting for heterogeneity. The present study analyzed eighteen datasets from sixteen observational studies. The results of the meta-analysis demonstrated a statistically significant increase in blood resistin levels among women with PE compared to the control group. (standardized mean difference=0.35, 95% confidence interval: 0.16 to 0.54, p<0.001; I2=74%). The findings of the subgroup analysis indicate that various study characteristics, including study design, timing, and methods for measuring resistin, matching of body mass index between cases and controls, and study quality scores did not exert a significant impact on the outcomes. Nonetheless, it is noteworthy that the diagnostic criteria for PE employed in the studies included in the analysis may have influenced the results (p for subgroup difference=0.001). Women with preeclampsia exhibit a greater concentration of resistin in circulation when compared to healthy pregnant controls.


Subject(s)
Pre-Eclampsia , Resistin , Female , Humans , Pregnancy , Leptin , Adiponectin , Adipokines
10.
Methods Mol Biol ; 2718: 167-179, 2023.
Article in English | MEDLINE | ID: mdl-37665460

ABSTRACT

Proteins are crucial for controlling different cellular processes by perceiving and converting external environmental cues into cellular responses. Therefore, regulation of protein activities is pivotal for the development and survival of an organism. This is often mediated by posttranslational modifications, which usually are carried out on specific residues of a target protein by a "writer" protein. The (reversible) modifications of different residues may lead to different signaling outputs. In the case of protein phosphorylation, one of the most common posttranslational modifications, this writer protein is a protein kinase. In this chapter, we report a comprehensive and versatile workflow to identify the phosphorylation profile of a target protein in plants from a putative kinase-target pair by combining an in planta phosphorylation assay and mass spectrometry analysis.


Subject(s)
Biological Assay , Protein Processing, Post-Translational , Phosphorylation , Cues , Mass Spectrometry
11.
Front Plant Sci ; 14: 1250878, 2023.
Article in English | MEDLINE | ID: mdl-37674736

ABSTRACT

Changes in weather patterns with emerging drought risks and rising global temperature are widespread and negatively affect crop growth and productivity. In nature, plants are simultaneously exposed to multiple biotic and abiotic stresses, but most studies focus on individual stress conditions. However, the simultaneous occurrence of different stresses impacts plant growth and development differently than a single stress. Plants sense the different stress combinations in the same or in different tissues, which could induce specific systemic signalling and acclimation responses; impacting different stress-responsive transcripts, protein abundance and modifications, and metabolites. This mini-review focuses on the combination of drought and heat, two abiotic stress conditions that often occur together. Recent omics studies indicate common or independent regulators involved in heat or drought stress responses. Here, we summarize the current research results, highlight gaps in our knowledge, and flag potential future focus areas.

12.
Mol Biotechnol ; 2023 Aug 17.
Article in English | MEDLINE | ID: mdl-37592151

ABSTRACT

Colon cancer (CC) is a malignant disease of the digestive tract, and its rising prevalence poses a grave threat to people's health. N6-methyladenosine (m6A) modification is essential for various crucial life processes through modulating gene expression. Methyltransferase-like 14 (METTL14), the m6A methylation transferase core protein, and its aberrant expression is intimately correlated to tumor development. This study was conducted to probe the impacts and specific mechanisms of METTL14 on the biological process of CC. Bioinformatics data disclosed that METTL14 was significantly attenuated in CC. Functional assays were executed to ascertain how METTL14 affected CC tumorigenicity, and METTL14 overexpression caused a notable decline in viability, migration, invasion, and stemness phenotype of CC cells. Then, in-depth mechanistic studies displayed that stearoyl-CoA desaturase 1 (SCD1) was a downstream target gene of METTL14-mediated m6A modification. METTL14 overexpression substantially augmented the m6A modification of SCD1 mRNA and diminished the SCD1 mRNA level. In addition, we revealed that YTHDF2 was the m6A reader to recognize METTL14 m6A-modified SCD1 mRNA and abolish its stability. Finally, we also validated that METTL14 might impede the tumorigenic process of CC through SCD1 mediated Wnt/ß-catenin signaling. Taken together, this study presented that METTL14 performed as a potential therapeutic target in CC with important implications for the prognosis amelioration of CC patients.

13.
Mol Neurobiol ; 60(11): 6715-6730, 2023 Nov.
Article in English | MEDLINE | ID: mdl-37477767

ABSTRACT

Humans exhibit a rich intestinal microbiome that contain high levels of bacteria capable of producing 3-oxo-lithocholic acid (3-oxoLCA) and other secondary bile acids (BAs). The molecular mechanism mediating the role of 3-oxoLCA in cerebral ischemia-reperfusion (I/R) injury remains unclear. We investigated the role of 3-oxoLCA in a rat cerebral I/R injury model. We found that the concentrations of 3-oxoLCA within the cerebrospinal fluid were increased following I/R. In the in vitro oxygen-glucose deprivation (OGD) model, the levels of intraneuronal 3-oxoLCA was elevated following OGD insult. We showed that the increase of membrane ASBT (apical sodium-dependent bile acid transporter) contributed to OGD-induced elevation of intraneuronal 3-oxoLCA. Increasing intraneuronal 3-oxoLCA promoted ischemia-induced neuronal death, whereas reducing 3-oxoLCA levels were neuroprotective. Our results revealed that PLOD2 (procollagen-lysine, 2-oxoglutarate 5-dioxygenases 2) functioned upstream of PTEN (the phosphatase and tensin homolog deleted on chromosome 10) and downstream of 3-oxoLCA to promote OGD-induced neuronal injury. We further demonstrated that direct-current stimulation (DCS) decreased the levels of intraneuronal 3-oxoLCA and membrane ASBT in OGD-insulted neurons, while bilateral transcranial DCS (tDCS) reduced brain infarct volume following I/R by inhibiting ASBT. Together, these data suggest that increased expression of ASBT promotes neuronal death via 3-oxoLCA-PLOD2-PTEN signaling pathway. Importantly, bilateral tDCS suppresses ischemia-induced increase of ASBT, thereby conferring neuroprotection after cerebral I/R injury.


Subject(s)
Brain Ischemia , Reperfusion Injury , Transcranial Direct Current Stimulation , Humans , Rats , Animals , Neuroprotection , Signal Transduction , Brain Ischemia/metabolism , Oxygen/metabolism , Cerebral Infarction , Glucose/metabolism , Reperfusion Injury/metabolism , Apoptosis , Procollagen-Lysine, 2-Oxoglutarate 5-Dioxygenase/metabolism , PTEN Phosphohydrolase/metabolism
14.
EMBO Rep ; 24(9): e54709, 2023 09 06.
Article in English | MEDLINE | ID: mdl-37458257

ABSTRACT

Endocytosis regulates the turnover of cell surface localized receptors, which are crucial for plants to rapidly respond to stimuli. The evolutionary ancient TPLATE complex (TPC) plays an essential role in endocytosis in Arabidopsis plants. Knockout or knockdown of single TPC subunits causes male sterility and seedling lethality phenotypes, complicating analysis of the roles of TPC during plant development. Partially functional alleles of TPC subunits however only cause mild developmental deviations. Here, we took advantage of the partially functional TPLATE allele, WDXM2, to investigate a role for TPC-dependent endocytosis in receptor-mediated signaling. We discovered that reduced TPC-dependent endocytosis confers a hypersensitivity to very low doses of CLAVATA3 peptide signaling. This hypersensitivity correlated with the abundance of the CLAVATA3 receptor protein kinase CLAVATA1 at the plasma membrane. Genetic and biochemical analysis as well as live-cell imaging revealed that TPC-dependent regulation of CLAVATA3-dependent internalization of CLAVATA1 from the plasma membrane is required for shoot stem cell homeostasis. Our findings provide evidence that TPC-mediated endocytosis and degradation of CLAVATA1 is a mechanism to dampen CLAVATA3-mediated signaling during plant development.


Subject(s)
Arabidopsis Proteins , Arabidopsis , Arabidopsis/genetics , Arabidopsis Proteins/genetics , Endocytosis , Gene Expression Regulation, Plant , Meristem/genetics , Plants/metabolism , Receptors, Cell Surface/metabolism , Signal Transduction
15.
Bioeng Transl Med ; 8(4): e10534, 2023 Jul.
Article in English | MEDLINE | ID: mdl-37476057

ABSTRACT

Formation of functional and perfusable vascular network is critical to ensure the long-term survival and functionality of the engineered tissue tracheae after transplantation. However, the greatest challenge in tracheal-replacement therapy is the promotion of tissue regeneration by rapid graft vascularization. Traditional prevascularization methods for tracheal grafts typically utilize omentum or muscle flap wrapping, which requires a second operation; vascularized segment tracheal orthotopic transplantation in one step remains difficult. This study proposes a method to construct a tissue-engineered tracheal graft, which directly forms the microvascular network after orthotopic transplantation in vivo. The focus of this study was the preparation of a hybrid tracheal graft that is non-immunogenic, has good biomechanical properties, supports cell proliferation, and quickly vascularizes. The results showed that vacuum-assisted decellularized trachea-polycaprolactone hybrid scaffold could match most of the above requirements as closely as possible. Furthermore, endothelial progenitor cells (EPCs) were extracted and used as vascularized seed cells and seeded on the surfaces of hybrid grafts before and during the tracheal orthotopic transplantation. The results showed that the microvascularized tracheal grafts formed maintained the survival of the recipient, showing a satisfactory therapeutic outcome. This is the first study to utilize EPCs for microvascular construction of long-segment trachea in one-step; the approach represents a promising method for microvascular tracheal reconstruction.

16.
Eur J Neurosci ; 58(5): 3330-3346, 2023 09.
Article in English | MEDLINE | ID: mdl-37452630

ABSTRACT

Isoleucine is a branched chain amino acid. The role of isoleucine in cerebral ischemia-reperfusion injury remains unclear. Here, we show that the concentration of isoleucine is decreased in cerebrospinal fluid in a rat model of cerebral ischemia-reperfusion injury, the rat middle cerebral artery occlusion (MCAO). To our surprise, the level of intraneuronal isoleucine is increased in an in vitro model of cerebral ischemia injury, the oxygen-glucose deprivation (OGD). We found that the increased activity of LAT1, an L-type amino acid transporter 1, leads to the elevation of intraneuronal isoleucine after OGD insult. Reducing the level of intraneuronal isoleucine promotes cell survival after cerebral ischemia-reperfusion injury, but supplementing isoleucine aggravates the neuronal damage. To understand how isoleucine promotes ischemia-induced neuronal death, we reveal that isoleucine acts upstream to reduce the expression of CBFB (core binding factor ß, a transcript factor involved in cell development and growth) and that the phosphatase PTEN acts downstream of CBFB to mediate isoleucine-induced neuronal damage after OGD insult. Interestingly, we demonstrate that direct-current stimulation reduces the level of intraneuronal isoleucine in cortical cultures subjected to OGD and that transcranial direct-current stimulation (tDCS) decreases the cerebral infarct volume of MCAO rat through reducing LAT1-depencent increase of intraneuronal isoleucine. Together, these results lead us to conclude that LAT1 over activation-dependent isoleucine-CBFB-PTEN signal transduction pathway may mediate ischemic neuronal injury and that tDCS exerts its neuroprotective effect by suppressing LAT1 over activation-dependent signalling after cerebral ischemia-reperfusion injury.


Subject(s)
Brain Ischemia , Neuroprotective Agents , Reperfusion Injury , Transcranial Direct Current Stimulation , Rats , Animals , Isoleucine/pharmacology , Neuroprotection , Brain Ischemia/metabolism , Signal Transduction , Infarction, Middle Cerebral Artery/metabolism , Reperfusion Injury/metabolism , Neuroprotective Agents/pharmacology , Oxygen
17.
J Phys Chem Lett ; 14(19): 4419-4425, 2023 May 18.
Article in English | MEDLINE | ID: mdl-37140962

ABSTRACT

Here, we investigate the photoconductivity of gallium oxide thin films at different temperatures using time-resolved terahertz spectroscopy. The photogenerated electrons in the conduction band show a monoexponential decay, implying a first-order electron depopulation mechanism. The electron lifetime increases with rising temperature, and this trend coincides with the temperature dependence of the electron mobility rather than diffusion coefficient, suggesting that electron-hole recombination is determined by directional electron drift instead of random diffusion. The electron mobilities extracted from the transient terahertz conductivity are substantially greater than the previously reported Hall mobilities over a wide temperature range, and this is probably because the electron drift in response to the terahertz field is immune from scattering with macroscopic defects. Thus, the mobilities measured here may represent the intrinsic limit of the electron mobility in gallium oxide crystals. Our finding suggests that the current Hall mobility in this wide bandgap semiconductor is still far below the limit, and the long-range electron transport can be further increased by improving the crystalline quality.

18.
Data Brief ; 48: 109139, 2023 Jun.
Article in English | MEDLINE | ID: mdl-37113498

ABSTRACT

The data shown in this article are related to the published paper entitled "A novel 4-O-endosulfatase with high potential for the structure-function studies of chondroitin sulfate/dermatan sulfate" in Carbohydrate Polymers. In this article, the phylogenetic analysis, cloning, expression, purification, specificity and biochemical characteristics of the identified chondroitin sulfate/dermatan sulfate 4-O-endosulfatase (endoBI4SF) are described in detail. The recombinant endoBI4SF with a molecular mass of 59.13 kDa can can specifically hydrolyze the 4-O- but not 2-O- and 6-O-sulfate groups in the oligo-/polysaccharides of chondroitin sulfate/dermatan sulfate and show the maximum reaction rate in 50 mM Tris-HCl buffer (pH 7.0) at 50°C, which can be a very useful tool for the structural and functional studies of chondroitin sulfate/dermatan sulfate.

19.
Molecules ; 28(7)2023 Mar 31.
Article in English | MEDLINE | ID: mdl-37049897

ABSTRACT

When compared to expensive lithium metal, the metal sodium resources on Earth are abundant and evenly distributed. Therefore, low-cost sodium-ion batteries are expected to replace lithium-ion batteries and become the most likely energy storage system for large-scale applications. Among the many anode materials for sodium-ion batteries, hard carbon has obvious advantages and great commercial potential. In this review, the adsorption behavior of sodium ions at the active sites on the surface of hard carbon, the process of entering the graphite lamellar, and their sequence in the discharge process are analyzed. The controversial storage mechanism of sodium ions is discussed, and four storage mechanisms for sodium ions are summarized. Not only is the storage mechanism of sodium ions (in hard carbon) analyzed in depth, but also the relationships between their morphology and structure regulation and between heteroatom doping and electrolyte optimization are further discussed, as well as the electrochemical performance of hard carbon anodes in sodium-ion batteries. It is expected that the sodium-ion batteries with hard carbon anodes will have excellent electrochemical performance, and lower costs will be required for large-scale energy storage systems.

20.
Toxics ; 11(4)2023 Mar 28.
Article in English | MEDLINE | ID: mdl-37112543

ABSTRACT

Polycyclic aromatic hydrocarbons (PAHs) are an important class of pollutants in China. The land use regression (LUR) model has been used to predict the selected PAH concentrations and screen the key influencing factors. However, most previous studies have focused on particle-associated PAHs, and research on gaseous PAHs was limited. This study measured representative PAHs in both gaseous phases and particle-associated during the windy, non-heating and heating seasons from 25 sampling sites in different areas of Taiyuan City. We established separate prediction models of 15 PAHs. Acenaphthene (Ace), Fluorene (Flo), and benzo [g,h,i] perylene (BghiP) were selected to analyze the relationship between PAH concentration and influencing factors. The stability and accuracy of the LUR models were quantitatively evaluated using leave-one-out cross-validation. We found that Ace and Flo models show good performance in the gaseous phase (Ace: adj. R2 = 0.14-0.82; Flo: adj. R2 = 0.21-0.85), and the model performance of BghiP is better in the particle phase (adj. R2 = 0.20-0.42). Additionally, better model performance was observed in the heating season (adj R2 = 0.68-0.83) than in the non-heating (adj R2 = 0.23-0.76) and windy seasons (adj R2 = 0.37-0.59). Those gaseous PAHs were highly affected by traffic emissions, elevation, and latitude, whereas BghiP was affected by point sources. This study reveals the strong seasonal and phase dependence of PAH concentrations. Building separate LUR models in different phases and seasons improves the prediction accuracy of PAHs.

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