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1.
Sci Rep ; 14(1): 20614, 2024 Sep 04.
Artículo en Inglés | MEDLINE | ID: mdl-39232041

RESUMEN

The unmanned aerial vehicle (UAV) city patrol is of great significance in ensuring the safety of residents' lives and properties, as well as maintaining the normal operation of the city. However, the detection of UAV images faces challenges such as numerous small-scale objects, complex backgrounds, and high requirements for detection speed. In response to these issues, we introduce a Real-time Small Object Detection network in UAV-vision (RTS-Net), tailored for UAV patrols. Initially, we introduce a multiscale feature fusion module (MFFM) designed to augment the expressiveness of features across scales, thereby enhancing the detection of smaller objects. Subsequently, leveraging attention mechanisms, we present the coordinated attention detection module (CADM), which bolsters the detection model's ability to accurately segregate objects from the background in expansive, complex scenarios. Lastly, a lightweight real-time feature extraction module (RFEM) is crafted to diminish model computational complexity and boost inference speed. On the UAV road patrol image dataset we constructed, our proposed method attains a detection accuracy of 89.9 % mAP, breaking previous records. It surpasses all prevailing detection methods, particularly for small-scale objects. Simultaneously, it achieves an inference speed of 163.9 FPS. The experimental results show that RTS-Net can satisfy the accurate and efficient detection of ground objects by various different UAV platforms in different complex scenarios.

2.
Anim Nutr ; 18: 380-389, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-39296492

RESUMEN

The objective of this study was to examine the early serum proteomic and inflammatory profiles of weaned piglets subjected to iron deficiency. Twelve healthy piglets (Duroc × Landrace × Large Yorkshire, body weight: 4.96 ± 0.05 kg) were weaned at 21 days of age. Subsequently, these animals were randomly allocated to one of two groups, with six replicates in each group (maintaining a male-to-female ratio of 1:1), the control group (administered 100 mg/kg Fe as FeSO4·H2O) and L-Fe group (no additional Fe supplementation). The results showed that 42 days after initiating, compared with control group, routine blood analysis revealed a reduction in serum iron content, red blood cell (RBC) count, hemoglobin (HGB) content, hematocrit (HCT), and mean corpuscular volume (MCV) (P < 0.05). Subsequent sample analysis indicated a noteworthy decrease in iron deposition in the liver, spleen, and kidneys of piglets fed the L-Fe diet compared with control group (P < 0.05). However, final body weight, average daily gain (ADG), average daily feed intake (ADFI), feed conversion ratio, and tissue coefficients were similar between the two groups (P > 0.05). During the early stages of iron deficiency, piglets exhibited increased villus height (VH) and the ratio of VH to crypt depth (CD) in the duodenum (P < 0.05) and increased expression levels of iron transporters, including duodenal cytochrome (Cybrd), divalent metal transport 1 (DMT1), and ferritin light chain (FTL) (P < 0.05). Subsequently, isobaric tags for relative and absolute quantitation (iTRAQ) were used to identify serum proteins. Gene Ontology (GO) analysis of the differentially abundant proteins (DAP) revealed that 24 of the 30 DAP were involved in platelet function, immune response, cellular metabolism, transcription, and protein synthesis. Notably, prothrombin, asporin (ASPN), and Rac family small GTPase 3 (RAC3) expression was induced, whereas glycoprotein Ib platelet subunit alpha (GPIbA) expression was decreased. This was accompanied by a substantial reduction in serum complement 3 (C3) and complement 4 (C4) contents (P < 0.05), with elevated the contents of interleukin-1ß (IL-1ß), interleukin-4 (IL-4), interleukin-6 (IL-6), transforming growth factor-ß1 (TGF-ß1), and tumor necrosis factor-α (TNF-α) (P < 0.05). Our findings underscore the essential role of dietary iron supplementation in maintaining iron homeostasis and modulating inflammatory responses in piglets.

3.
Nat Commun ; 15(1): 8140, 2024 Sep 17.
Artículo en Inglés | MEDLINE | ID: mdl-39289397

RESUMEN

Continuous directed evolution of base editors (BEs) has been successful in bacteria cells, but not yet in mammalian cells. Here, we report the development of a Continuous Directed Evolution system in Mammalian cells (CDEM). CDEM enables the BE evolution in a full-length manner with Cas9 nickase. We harness CDEM to evolve the deaminases of cytosine base editor BE3 and adenine base editors, ABEmax and ABE8e. The evolved cytidine deaminase variants on BE4 architecture show not only narrowed editing windows, but also higher editing purity and low off-target activity without a trade-off in on-targeting activity. The evolved ABEmax and ABE8e variants exhibit narrowed or shifted editing windows to different extents, and lower off-target effects. The results illustrate that CDEM is a simple but powerful approach to continuously evolve BEs without size restriction in the mammalian environment, which is advantageous over continuous directed evolution system in bacteria cells.


Asunto(s)
Adenina , Sistemas CRISPR-Cas , Citidina Desaminasa , Citidina , Evolución Molecular Dirigida , Edición Génica , Edición Génica/métodos , Humanos , Adenina/metabolismo , Evolución Molecular Dirigida/métodos , Citidina/metabolismo , Citidina/genética , Citidina Desaminasa/metabolismo , Citidina Desaminasa/genética , Células HEK293 , Proteína 9 Asociada a CRISPR/metabolismo , Proteína 9 Asociada a CRISPR/genética , Animales
4.
Pharmacol Res ; 209: 107407, 2024 Sep 11.
Artículo en Inglés | MEDLINE | ID: mdl-39270946

RESUMEN

Renal fibrosis (RF) is a common endpoint of various chronic kidney diseases, leading to functional impairment and ultimately progressing to end-stage renal failure. Glycolytic reprogramming plays a critical role in the pathogenesis of fibrosis, which maybe a potential therapeutic target for treating renal fibrosis. Here, we revealed the novel role of ZEB1 in renal fibrosis, and whether targeting ZEB1 is the underlying mechanism for the anti-fibrotic effects of ethyl caffeate (EC) to regulate the glycolytic process. Treatment of EC attenuated the renal fibrosis and inhibited ZEB1 expression in vivo and in vitro, reducing the upregulated expression of glycolytic enzymes (HK2, PKM2, PFKP) and key metabolites (lactic acid, pyruvate). ZEB1 overexpression promoted the renal fibrosis and glycolysis, whereas knockout of ZEB1 apparently attenuated renal fibrosis in vivo and in vitro. EC interacted with ZEB1 to modulate the glycolytic enzymes for suppressing the elevated glycolytic reprogramming during renal fibrosis. In summary, our study reveals that ZEB1 plays an important role in regulating glycolytic reprogramming during the renal tubular epithelial cell fibrosis, suggesting inhibition of ZEB1 may be a potential strategy for treating renal fibrosis. Additionally, EC is a potential new drug candidate for the treatment of renal fibrosis and CKD.

5.
Adv Sci (Weinh) ; : e2406924, 2024 Sep 24.
Artículo en Inglés | MEDLINE | ID: mdl-39316064

RESUMEN

Current induced spin-orbit torque (SOT) manipulation of magnetization is pivotal in spintronic devices. However, its application for perpendicular magnetic anisotropy magnets, crucial for high-density storage and memory devices, remains nondeterministic and inefficient. Here, a highly efficient approach is demonstrated to generate collinear spin currents by artificial modulation of interfacial symmetry, achieving 100% current-induced field-free SOT switching in CoFeB multilayers with perpendicular magnetization on stepped Al2O3 substrates. This field-free switching is primarily driven by the out-of-plane anti-damping SOT generated by the planar spin Hall effect (PSHE), resulting from reduced interface symmetry due to orientation-determined steps. Microscopic theoretical analysis confirms the presence and significance of PSHE in this process. Notably, this method for generating out-of-plane spin polarization along the collinear direction of the spin-current with artificial modulation of interfacial symmetry, overcomes inherent material symmetry constraints. These findings provide a promising avenue for universal control of spin-orbit torque, addressing challenges associated with low crystal symmetry and highlighting its great potential to advance the development of energy-efficient spintronic devices technology.

6.
Bioresour Technol ; 412: 131412, 2024 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-39226944

RESUMEN

Simultaneous nitrification-denitrification (SND) is a promising nitrogen removal process. However, total nitrogen (TN) removal is limited due to unsatisfactory denitrification. This study demonstrated that short-time (1 h) pre-anoxic electro-stimulation significantly enhanced SND efficiency in the aerobic phase by promoting the proliferation of mixotrophic and heterotrophic denitrifiers. SND and TN removal efficiencies at the optimal electric current (EC) (0.02 A) were 85.6 % and 93.9 %, which were 39.1 % and 17.2 % higher than control. Microbial community analysis indicated that the abundance of mixotrophic and heterotrophic denitrifiers significantly increased. H2 generated in the electro-stimulation process induced the proliferation of mixotrophic denitrifiers. The weak EC (0.02 A) promoted the activity and growth of heterotrophic denitrifiers by accelerating electron transfer. They concurrently mediated heterotrophic denitrification to enhance SND efficiency. PICRUSt2 analysis revealed that the abundance of denitrifying genes dramatically surged. This study provides new insights into applying electrolysis to achieve advanced SND while minimizing electricity consumption.


Asunto(s)
Biopelículas , Reactores Biológicos , Desnitrificación , Electrólisis , Nitrificación , Nitrógeno , Reactores Biológicos/microbiología , Nitrógeno/metabolismo , Electricidad , Bacterias/metabolismo
7.
Artículo en Inglés | MEDLINE | ID: mdl-39268654

RESUMEN

Mimicking fundamental synaptic working principles with memristors contributes an essential step toward constructing brain-inspired, high-efficiency neuromorphic systems that surpass von Neumann system computers. Here, an electroforming-free planar-type memristor based on a CsPbBr3 single crystal is proposed and exhibits excellent resistive switching (RS) behaviors including stable endurance, ultralow power consumption, and fast switching speed. Furthermore, an optically tunable RS performance is demonstrated by manipulating irradiation intensity and wavelength. Optical analysis techniques such as steady-state photoluminescence and time-resolved photoluminescence are employed to investigate the distribution of Br ions and vacancies before and after quantitative polarization, describing migration dynamic processes to elucidate the RS mechanism. Importantly, a CsPbBr3 single crystal, as the optoelectronic synapse, shows unique potential to emulate photoenhanced synaptic functions such as excitatory postsynaptic current, paired-pulse facilitation, long-term potentiation/depression, spike-timing-dependent plasticity, spike-voltage-dependent plasticity, and learning-forgetting-relearning process with ultralow per synapse event energy consumption. A classical Pavlov's dog experiment is simulated with a combination of optical and electrical stimulation. Finally, pattern recognition with simulated artificial neural networks based on our synapse reached an accuracy of 93.11%. The special strategy and superior RS characteristics of optoelectronic synapses provide a pathway toward high-performance, energy-efficient neuromorphic electronics.

8.
Front Microbiol ; 15: 1452499, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39252836

RESUMEN

During an investigation of fungal diversity from freshwater environments in different regions in Jiangxi Province, China, four interesting species were collected. Morphology coupled with combined gene analysis of an ITS, LSU, SSU, and rpb2 DNA sequence data showed that they belong to the family Pleurotheciaceae. Four new species, Pleurotheciella ganzhouensis, Pla. irregularis, Pla. verrucosa, and Pleurothecium jiangxiense are herein described. Pleurotheciella ganzhouensis is characterized by its capsule-shaped conidia and short conidiophores, while Pla. irregularis has amorphous conidiophores and 3-septate conidia. Pleurotheciella verrucosa has cylindrical or verrucolose conidiogenous cells, 1-septate, narrowly fusiform, meniscus or subclavate conidia. Pleurothecium jiangxiense characterized in having conidiogenous cells with dense cylindrical denticles and short conidiophores. Pleurothecium obovoideum was transferred to Neomonodictys based on phylogenetic evidence. All species are compared with other similar species and comprehensive descriptions, micrographs, and phylogenetic data are provided.

9.
Biosens Bioelectron ; 267: 116788, 2024 Sep 19.
Artículo en Inglés | MEDLINE | ID: mdl-39316869

RESUMEN

m6A methylation detection is crucial for understanding RNA functions, revealing disease mechanisms, guiding drug development and advancing epigenetics research. Nevertheless, high-throughput sequencing and liquid chromatography-based traditional methods still face challenges to rapid and direct detection of m6A methylation. Here we report a DNAzyme-based and smartphone-assisted electrochemical biosensor for rapid detection of m6A. We initially identified m6A methylation-sensitive DNAzyme mutants through site mutation screening. These mutants were then combined with tetrahedral DNA to modify the electrodes, creating a 3D sensing interface. The detection of m6A was accomplished by using DNAzyme to capture and cleave the m6A sequence. The electrochemical biosensor detected the m6A sequence at nanomolar concentrations with a low detection limit of 0.69 nM and a wide detection range from 10 to 104 nM within 60 min. As a proof of concept, the 3'-UTR sequence of rice was selected as the m6A analyte. Combined with a smartphone, our biosensor shows good specificity, sensitivity, and easy-to-perform features, which indicates great prospects in the field of RNA modification detection and epigenetic analysis.

10.
J Hazard Mater ; 479: 135762, 2024 Nov 05.
Artículo en Inglés | MEDLINE | ID: mdl-39255666

RESUMEN

Spread of antibiotic resistance genes (ARGs) in aquatic ecosystems poses a significant global challenge to public health. The potential effects of water temperature perturbation induced by specific water environment changes on ARGs transmission are still unclear. The conjugate transfer of plasmid-mediated ARGs under water temperature perturbation was investigated in this study. The conjugate transfer frequency (CTF) was only 7.16 × 10-7 at a constant water temperature of 5 °C, and it reached 2.18 × 10-5 at 30 °C. Interestingly, compared to the constant 5 °C, the water temperature perturbations (cooling and warming models between 5-30 °C) significantly promoted the CTF. Intracellular reactive oxygen species was a dominant factor, which not only directly affected the CTF of ARGs, but also functioned indirectly via influencing the cell membrane permeability and cell adhesion. Compared to the constant 5 °C, water temperature perturbations significantly elevated the gene expression associated with intercellular contact, cell membrane permeability, oxidative stress responses, and energy driven force for CTF. Furthermore, based on the mathematical model predictions, the stabilization times of acquiring plasmid maintenance were shortened to 184 h and 190 h under cooling and warming model, respectively, thus the water temperature perturbations promoted the ARGs transmission in natural conditions compared with the constant low temperature conditions.


Asunto(s)
Plásmidos , Especies Reactivas de Oxígeno , Temperatura , Especies Reactivas de Oxígeno/metabolismo , Plásmidos/genética , Farmacorresistencia Microbiana/genética , Agua/química , Antibacterianos/farmacología , Genes Bacterianos , Transferencia de Gen Horizontal , Escherichia coli/genética , Escherichia coli/efectos de los fármacos , Farmacorresistencia Bacteriana/genética , Permeabilidad de la Membrana Celular/efectos de los fármacos , Microbiología del Agua
11.
Anal Bioanal Chem ; 2024 Sep 19.
Artículo en Inglés | MEDLINE | ID: mdl-39297935

RESUMEN

It is of significant importance to public health that reliable monitoring of nitroimidazoles be conducted, while certified reference materials (CRMs) are essential for accurate and reliable detection. A project has been initiated with the objective of developing nitroimidazole purity CRMs to ensure that results from nationwide monitoring laboratories for nitroimidazoles in antibiotic residues can be compared and traced. The candidates were successively characterized in terms of their structure by means of infrared (IR) spectroscopy and mass spectrometry (MS). The mass balance (MB) method and the quantitative nuclear magnetic resonance (qNMR) method were utilized to determine the purity of nitroimidazoles with remarkable accuracy. Furthermore, a methodical investigation was conducted on homogeneity, stability, and uncertainty. Six nitroimidazole purity CRMs, including tinidazole (GBW09252), secnidazole (GBW09286), ronidazole (GBW09288), metronidazole (GBW(E)090755), dimetridazole (GBW(E)090819), and ornidazole (GBW(E)090820), were finally manufactured following authorization from China's State Administration for Market Regulation (SAMR). By using these CRMs, it is possible to improve the traceability, accuracy, and comparability of nitroimidazole measurements in a range of agricultural products, protecting public health.

12.
Zhongguo Xiu Fu Chong Jian Wai Ke Za Zhi ; 38(9): 1111-1116, 2024 Sep 15.
Artículo en Chino | MEDLINE | ID: mdl-39300887

RESUMEN

Objective: To explore the feasibility and effectiveness of free vastus lateralis flap combined with skin grafting for repairing small- and medium-sized lacunar defects in the non-weight-bearing area of diabetic foot. Methods: Between January 2022 and October 2023, 8 patients (8 feet) with small- and medium-sized lacunar defects in the non-weight-bearing area of diabetic foot were admitted. There were 6 males and 2 females, with an average age of 64.3 years (range, 58-76 years). The duration of the diabetic foot ulcer ranged from 2 to 7 weeks (mean, 4.3 weeks). The wound was located between the metatarsal bones in 4 cases, on the medial side of the foot in 2 cases, on the lateral side of the foot in 1 case, and on the dorsal and lateral sides of the foot in 1 case. The length of wound was 4.0-12.0 cm, the width was 3.0-5.0 cm, and the depth was 1.2-2.0 cm. The free vastus lateralis flaps were designed to repair the wounds, and skin grafting covered the vastus lateralis flaps. The length of the vastus lateralis flap was 5.0-14.0 cm, the width was 3.5-6.0 cm, and the thickness was 1.0-1.5 cm. The donor sites of the muscle flaps were directly sutured. Results: The time for vastus lateralis flaps harvested ranged from 30 to 80 minutes (mean, 55.0 minutes), and the total operation time ranged from 125 to 170 minutes (mean, 147.5 minutes). All muscle flaps and skin grafts survived successfully, and the wounds and the incisions at the donor sites healed by first intention. All patients were followed up 6-24 months, with an average of 12.8 months. The appearances of 3 patients who did not follow the doctor's instructions for pressure treatment of the muscle flaps were a little bloated, and the rest had a good appearance. The texture of the muscle flaps was soft. There were linear scars at the donor sites. There was no recurrence of ulcers during follow-up. All patients could walk independently without limitation of daily activities at last follow-up. Conclusion: The application of free vastus lateralis flap combined with skin grafting to repair small- and medium-sized lacunar defects in the non-weight-bearing area of diabetic foot has the advantages of simple operation and time-saving as well as small damage to the donor site, with good repair effect, especially for the elderly patients who are not suitable for prolonged anesthesia.


Asunto(s)
Pie Diabético , Colgajos Tisulares Libres , Procedimientos de Cirugía Plástica , Trasplante de Piel , Cicatrización de Heridas , Humanos , Pie Diabético/cirugía , Persona de Mediana Edad , Masculino , Femenino , Trasplante de Piel/métodos , Anciano , Procedimientos de Cirugía Plástica/métodos , Músculo Cuádriceps/trasplante , Resultado del Tratamiento
13.
Adv Sci (Weinh) ; : e2406211, 2024 Sep 20.
Artículo en Inglés | MEDLINE | ID: mdl-39301916

RESUMEN

As a structural protein of SARS-CoV-2, the envelope (E) protein not only plays a key role in the formation of viral particles, but also forms ion channels and has pathogenic functions, including triggering cell death and inflammatory responses. The stability of E proteins is controlled by the host ubiquitin-proteasome system. By screening human deubiquitinases, it is found that ubiquitin-specific protease 33 (USP33) can enhance the stability of E proteins depending on its deubiquitinase activity, thereby promoting viral replication. In the absence of USP33, E proteins are rapidly degraded, leading to a reduced viral load and inflammation. Using lipid nanoparticle (LNP) encapsulation of siUSP33 by adjusting the lipid components (ionizable cationic lipids), siUSP33 is successfully delivered to mouse lung tissues, rapidly reducing USP33 expression in the lungs and maintaining knockdown for at least 14 days, effectively suppressing viral replication and virulence. This method of delivery allows efficient targeting of the lungs and a response to acute infections without long-term USP33 deficiency. This research, based on the deubiquitination mechanism of USP33 on the E protein, demonstrates that LNP-mediated siRNA delivery targeting USP33 plays a role in antiviral and anti-inflammatory responses, offering a novel strategy for the prevention and treatment of SARS-CoV-2.

14.
Nanomicro Lett ; 17(1): 9, 2024 Sep 26.
Artículo en Inglés | MEDLINE | ID: mdl-39325069

RESUMEN

Lithium-ion batteries (LIBs) have dominated the portable electronic and electrochemical energy markets since their commercialisation, whose high cost and lithium scarcity have prompted the development of other alkali-ion batteries (AIBs) including sodium-ion batteries (SIBs) and potassium-ion batteries (PIBs). Owing to larger ion sizes of Na+ and K+ compared with Li+, nanocomposites with excellent crystallinity orientation and well-developed porosity show unprecedented potential for advanced lithium/sodium/potassium storage. With enticing open rigid framework structures, Prussian blue analogues (PBAs) remain promising self-sacrificial templates for the preparation of various nanocomposites, whose appeal originates from the well-retained porous structures and exceptional electrochemical activities after thermal decomposition. This review focuses on the recent progress of PBA-derived nanocomposites from their fabrication, lithium/sodium/potassium storage mechanism, and applications in AIBs (LIBs, SIBs, and PIBs). To distinguish various PBA derivatives, the working mechanism and applications of PBA-templated metal oxides, metal chalcogenides, metal phosphides, and other nanocomposites are systematically evaluated, facilitating the establishment of a structure-activity correlation for these materials. Based on the fruitful achievements of PBA-derived nanocomposites, perspectives for their future development are envisioned, aiming to narrow down the gap between laboratory study and industrial reality.

15.
Endocrine ; 2024 Sep 25.
Artículo en Inglés | MEDLINE | ID: mdl-39320591

RESUMEN

BACKGROUND: Acromegaly has a high risk of abnormal glucose metabolism. The complexity of the glucose time series index (CGI) is calculated from refined composite multi-scale entropy analysis of the continuous glucose monitoring (CGM) data. CGI is a new indicator of glucose imbalance based on ambulatory glucose monitoring technology, which allows for earlier response to glucose metabolism imbalance and correlates with patient prognosis. OBJECTIVE: To compare the differences in glucose metabolic profile and CGI between acromegaly with normal glucose tolerance (NGT) and healthy subjects. METHODS: Eight newly diagnosed patients with acromegaly (GH group) and eight age- and gender-matched healthy subjects (Control group) were included in this study. All participants underwent oral glucose tolerance test (OGTT) and 72-h CGM. A refined composite multi-scale entropy analysis was performed on the CGM data to calculate the CGI and we compare the differences in glycemic profiles and CGI between the two groups. RESULTS: After OGTT, compared with the control group, patients in the GH group had higher 2 h blood glucose (BG) (mmol/L) [GH vs control, 6.7 (6.1, 7.0) vs 5.2 (3.8, 6.3), P = 0.012], 3 h BG [5.1 (3.8, 6.5) vs 4.0 (3.4, 4.2), P = 0.046], mean BG [6.3 (6.1, 6.5) vs 5.5 (5.1, 5.9), P = 0.002], 2 h insulin (mU/L) [112.9 (46.8, 175.5) vs 34.1 (17.1, 55.6), P = 0.009], and 3 h insulin [26.8 (17.1, 55.4) vs 10.4 (4.2, 17.8), P = 0.016]. CGI was lower in the GH group [2.77 (1.92, 3.15) vs 4.2 (3.3, 4.8), P = 0.008]. Spearman's correlation analysis showed insulin-like growth factor (IGF) (r = -0.897, P < 0.001) and mean glucose (r = -0.717, P = 0.003) were significantly negatively correlated with CGI. Multiple linear stepwise regression showed that IGF-1 (r = -0.652, P = 0.028) was independent factor associated with CGI in acromegaly. CONCLUSION: IGF-1 was significantly associated with CGI, and CGI may serve as a novel marker to evaluate glucose homeostasis in acromegaly with normal glucose tolerance.

16.
Heliyon ; 10(16): e36521, 2024 Aug 30.
Artículo en Inglés | MEDLINE | ID: mdl-39258200

RESUMEN

The corrosion resistance of M390 powder metallurgical martensitic stainless steel with different tempering temperatures was investigated by potentiodynamic polarization measurements, salt spray tests, and microstructural analyses utilizing scanning electron microscopy (SEM), X-ray diffraction (XRD), and transmission electron microscopy (TEM). The tempering temperature had no significant effect on the size and volume fraction of carbides. The corrosion resistance of M390 steel gradually deteriorated with increasing tempering temperature, and a loss passivation (LOP) effect was observed when tempered at 450 °C, 500 °C, and 550 °C. Transmission electron microscopy (TEM) analysis showed that the width of the Cr-depleted zones around the undissolved M7C3 carbides increased with increasing tempering temperature, while the Cr content in these zones decreased, which was the main reason for the deterioration of corrosion resistance. This study offers valuable insights into optimizing the tempering process to improve the corrosion resistance of M390 steel for practical applications.

17.
Environ Sci Technol ; 2024 Sep 18.
Artículo en Inglés | MEDLINE | ID: mdl-39292548

RESUMEN

The escalating concern of perfluoroalkyl and polyfluoroalkyl substances (PFAS), particularly at contaminated sites, has prompted extensive investigations. In this study, samples of multimedia including air, rhizosphere soil, and tissues of wheat at various growing stages were collected near a mega fluorochemical industrial park in China. Perfluorooctanoic acid (PFOA) was predominant in both air and soil with a strong correlation, highlighting air deposition as an important source in the terrestrial system. PFAS concentrations in wheat decreased in the stem and ear but increased in the leaves as wheat matured. Specifically, perfluorobutanoic acid (PFBA) dominated in the aboveground tissues in the full-life-cycle, except that PFOA surpassed and became predominant in leaves during the filling and maturing stages, hinting at an airborne source. For all PFAS, both bioaccumulation factors and translocation factors (TFs) were inversely correlated with the carbon chain length during the full-life-cycle. The obtained TF values were considerably higher than those obtained from ambient sites reported previously, further suggesting an unneglectable foliar uptake from air, which was estimated to be 25% for PFOA. Moreover, spray irrigation remarkably enhanced the absorption of PFAS in wheat via foliar uptake relative to flood irrigation. The estimated daily intake of PFBA via wheat consumption and air inhalation was 0.50 µg/kg/day for local residents, at least one magnitude higher than the corresponding threshold, suggesting an alarmingly high exposure risk.

18.
Angew Chem Int Ed Engl ; : e202409784, 2024 Sep 03.
Artículo en Inglés | MEDLINE | ID: mdl-39225426

RESUMEN

Subnanometer metal clusters show advantages over conventional metal nanoparticles in numerous catalytic reactions owing to their high percentage of exposed surface sites, abundance of under-coordinated metal sites and unique electronic structures. However, the applications of subnanometer metal clusters in high-temperature catalytic reactions (>600 °C) are still hindered, because of their low stability under harsh reaction conditions. In this work, we have developed a zeolite-confined bimetallic PtIn catalyst with exceptionally high stability against sintering. A combination of experimental and theoretical studies shows that the isolated framework In(III) species serve as the anchoring sites for Pt species, precluding the migration and sintering of Pt species in the oxidative atmosphere at ≥650 °C. The catalyst comprising subnanometer PtIn clusters exhibits long-term stability of >1000 h during a cyclic reaction-regeneration test for ethane dehydrogenation reaction.

19.
Artículo en Inglés | MEDLINE | ID: mdl-39234867

RESUMEN

A polycrystalline sample LuCrO3 has been characterized by neutron powder diffraction (NPD) and magnetization measurements. Its crystal structure has been Rietveld refined from NPD data in space group Pnma; this perovskite contains strongly tilted CrO6 octahedra with extremely bent Cr-O-Cr superexchange angles of ∼142°. The NPD data show that below Néel temperature (TN ≃ 131 K), the magnetic structure can be defined as an A-type antiferromagnetic arrangement of Cr3+ magnetic moments, aligned along the b axis, with a canting along the c axis. A noticeable magnetostrictive effect is observed in the unit-cell parameters and volume upon cooling down across TN. The AC magnetic susceptibility indicates the onset of magnetic ordering below 112.6 K; the magnetization isotherms below TN show a nonlinear behaviour that is associated with the described canting of the Cr3+ magnetic moments. From the Curie-Weiss law, the effective moment of the Cr3+ sublattice is found to be µeff = 3.55 µB (calculated 3.7 µB) while the ΘCW parameter yields a value of -155 K, indicating antiferromagnetic interactions. There is a conspicuous increase of TN upon the application of external pressure, which must be due to shortening of the Cr-O bond length under compression that increases the orbital overlap integral.

20.
Front Endocrinol (Lausanne) ; 15: 1390564, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39229377

RESUMEN

Aim: The aim of this research was to ascertain the correlations between alexithymia, social support, depression, and glycemic control in patients diagnosed with type 2 diabetes mellitus. Additionally, this study sought to delve into the potential mediating effects of social support and depression in the relationship between alexithymia and glycemic control. Method: A purposive sampling methodology was employed to select a cohort of 318 patients afflicted with type 2 diabetes mellitus, hailing from a care establishment situated in Chengdu City. This investigation embraced a cross-sectional framework, wherein instruments such as the General Information Questionnaire, the Toronto Alexithymia Scale 20, the Social Support Rating Scale, and the Hamilton Depression Scale were judiciously administered. The primary objective of this endeavor was to unravel the interplay that exists amongst alexithymia, social support, depression, and glycemic control. The inquiry discerned these interrelationships through both univariate and correlational analyses, subsequently delving into a comprehensive exploration of the mediating ramifications engendered by social support and depression in the nexus between alexithymia and glycemic control. Results: The HbA1c level of patients diagnosed with type 2 diabetes mellitus was recorded as (8.85 ± 2.107), and their current status with regards to alexithymia, social support, and depression were measured as (58.05 ± 4.382), (34.29 ± 4.420), and (7.17 ± 3.367), respectively. Significant correlations were found between HbA1c and alexithymia (R=0.392, P<0.01), social support (R=-0.338, P<0.01), and depression (R=0.509, P<0.01). Moreover, alexithymia correlation with social support (R=-0.357, P<0.01) and with depression (R=0.345, P<0.01). Regarding the mediation analysis, the direct effect of alexithymia on HbA1c was calculated to be 0.158, while the indirect effect through social support and depression were 0.086 and 0.149, respectively. The total effect value was determined to be 0.382, with the mediating effect accounting for 59.95%, and the direct effect accounting for 40.31%. Conclusion: Alexithymia exerts both direct and indirect adverse effects on glycemic control, thereby exacerbating disease outcomes. Hence, it is imperative to prioritize the mental health status of individuals with type 2 diabetes to enhance overall well-being, ameliorate diabetes-related outcomes, elevate patients' quality of life, and alleviate the psychological distress and financial burden associated with the condition.


Asunto(s)
Síntomas Afectivos , Depresión , Diabetes Mellitus Tipo 2 , Control Glucémico , Apoyo Social , Humanos , Diabetes Mellitus Tipo 2/psicología , Diabetes Mellitus Tipo 2/sangre , Diabetes Mellitus Tipo 2/complicaciones , Síntomas Afectivos/epidemiología , Femenino , Masculino , Persona de Mediana Edad , Depresión/epidemiología , Depresión/psicología , Estudios Transversales , Control Glucémico/psicología , Análisis de Clases Latentes , Adulto , Anciano , Hemoglobina Glucada/análisis , Hemoglobina Glucada/metabolismo , Glucemia/análisis , Glucemia/metabolismo
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