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1.
Front Pharmacol ; 15: 1439448, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39411061

RESUMEN

Introduction: Knee osteoarthritis (KOA) is a chronic degenerative bone metabolic disease that primarily affects older adults, leading to chronic pain and disability that affect patients' daily activities. Electroacupuncture (EA) is a commonly used method for the treatment of chronic pain in clinical practice. Previous studies indicate that the endocannabinoid system is involved in EA analgesia, but whether endocannabinopeptide VD-hemopressin (α) and RVD-hemopressin (α) derived from hemoglobin chains are involved in EA analgesia is unclear. Methods: RNA-seq technology was used to screen which genes involved in EA analgesia. The expression of hemoglobin α chain and 26S proteasome were determined by Western blotting. The level of VD-hemopressin (α) and RVD-hemopressin (α) were measured by UPLC-MS/MS. Microinjection VD-Hemopressin (α), RVD-Hemopressin (α) and 26S proteasome inhibitor MG-132 into vlPAG, then observe mechanical and thermal pain thresholds. Results: Therefore, we used RNA-seq to obtain differentially expressed genes Hba-a1 and Hba-a2 involved in EA analgesia in the periaqueductal gray (PAG), which were translated into the hemoglobin α chain. EA significantly increased the expression of the hemoglobin α chain and the level of hemopressin (α) and RVD-hemopressin (α). Microinjection of VD-hemopressin (α) and RVD-hemopressin (α) into the ventrolateral periaqueductal gray (vlPAG) mimicked the analgesic effect of EA, while CB1 receptor antagonist AM251 reversed this effect. EA significantly increased the expression of 26S proteasome in KOA mice. Microinjection of 26S proteasome inhibitor MG132 before EA prevented both the anti-allodynic effect and upregulation of the concentration of RVD-hemopressin (α) by EA treatment and upregulated the expression of the hemoglobin α chain. Discussion: Our data suggest that EA upregulated the concentration of VD-hemopressin (α) and RVD-hemopressin (α) through enhancement of the hemoglobin α chain degradation by 26S proteasome in the PAG, then activated the CB1 receptor, thereby exerting inhibition of chronic pain in a mouse model of KOA. These results provide new insights into the EA analgesic mechanisms and reveal possible targets for EA treatment of chronic pain.

2.
Micromachines (Basel) ; 15(9)2024 Sep 12.
Artículo en Inglés | MEDLINE | ID: mdl-39337804

RESUMEN

Amorphous carbon (a-C) has promising potential for temperature sensing due to its outstanding properties. In this work, an a-C thin film temperature sensor integrated with the MEMS silicon accelerometer was proposed, and a-C film was deposited on the fixed frame of the accelerometer chip. The a-C film was deposited by DC magnetron sputtering and linear ion beam, respectively. The nanostructures of two types of films were observed by SEM and TEM. The cluster size of sp2 was analyzed by Raman, and the content of sp2 and sp3 of the carbon film was analyzed by XPS. It showed that the DC-sputtered amorphous carbon film, which had a higher sp2 content, had better temperature-sensitive properties. Then, an integrated sensor chip was designed, and the structure of the accelerometer was simulated and optimized to determine the final sizes. The temperature sensor module had a sensitivity of 1.62 mV/°C at the input voltage of 5 V with a linearity of 0.9958 in the temperature range of 20~150 °C. The sensitivity of the sensor is slightly higher than that of traditional metal film temperature sensors. The accelerometer module had a sensitivity of 1.4 mV/g/5 V, a nonlinearity of 0.38%, a repeatability of 1.56%, a total thermomechanical noise of 509 µg over the range of 1 to 20 Hz, and an average thermomechanical noise density of 116 µg/√Hz, which is smaller than the input acceleration amplitude for testing sensitivity. Under different temperatures, the performance of the accelerometer was tested. This research provided significant insights into the convenient procedure to develop a high-performance, economical temperature-accelerometer-integrated MEMS sensor.

3.
Natl Sci Rev ; 11(10): nwae252, 2024 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-39301064

RESUMEN

While atomically precise metal nanoclusters (NCs) with unique structures and reactivity are very promising in catalysis, the spatial resistance caused by the surface ligands and structural instability poses significant challenges. In this work, Au25(Cys)18 NCs are encapsulated in multivariate metal-organic frameworks (MOFs) to afford Au25@M-MOF-74 (M = Zn, Ni, Co, Mg). By the MOF confinement, the Au25 NCs showcase highly enhanced activity and stability in the intramolecular cascade reaction of 2-nitrobenzonitrile. Notably, the interaction between the metal nodes in M-MOF-74 and Au25(Cys)18 is able to suppress the free vibration of the surface ligands on the Au25 NCs and thereby improve the accessibility of Au sites; meanwhile, the stronger interactions lead to higher electron density and core expansion within Au25(Cys)18. As a result, the activity exhibits the trend of Au25@Ni-MOF-74 > Au25@Co-MOF-74 > Au25@Zn-MOF-74 > Au25@Mg-MOF-74, highlighting the crucial roles of microenvironment modulation around the Au25 NCs by interaction between the surface ligands and MOF hosts.

4.
Ecotoxicol Environ Saf ; 284: 117004, 2024 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-39270416

RESUMEN

With the increase of cadmium content in the environment, the losses caused by cadmium-induced intestinal diseases to animal husbandry are increasing year by year. However, most of the on-going research activities focus on zoonotic diseases rather than exploring the mechanisms of animal disease occurrence from an anthropogenic environmental perspective. In this study, stressed Hu sheep under cadmium environmental exposure were selected to explore the mechanism of inflammatory bowel disease development. 16 s, untargeted metabolomics and transcriptomic multiomics were used to analyze the changes of their intestinal tract and intestinal contents. The results showed that the beneficial microorganisms (s_Ruminococcus_sp) in the Cd group were significantly decreased and the potentially harmful microorganisms were significantly enriched, and the changes of these microorganisms affected the changes of metabolites (caprylic acid) to a certain extent, resulting in a decrease in fatty acids in the intestine. Due to the combined effect of cadmium ion and fatty acid reduction, the PPAR signaling pathway was inhibited, and the fatty acid transport and binding were further reduced, causing very serious damage to the intestine. We revealed for the first time the mechanism of intestinal injury in Hu sheeps under cadmium environmental exposure and provided new prevention and treatment methods of intestinal diseases under the environmental exposure to trace metals.


Asunto(s)
Cadmio , Colon , Intestino Delgado , Receptores Activados del Proliferador del Peroxisoma , Transducción de Señal , Animales , Cadmio/toxicidad , Transducción de Señal/efectos de los fármacos , Ovinos , Intestino Delgado/efectos de los fármacos , Intestino Delgado/metabolismo , Receptores Activados del Proliferador del Peroxisoma/metabolismo , Colon/efectos de los fármacos , Colon/metabolismo , Inflamación/inducido químicamente , Exposición a Riesgos Ambientales/efectos adversos , Enfermedades de las Ovejas/inducido químicamente , Ácidos Grasos/metabolismo , Microbioma Gastrointestinal/efectos de los fármacos
5.
Nanomaterials (Basel) ; 14(17)2024 Aug 29.
Artículo en Inglés | MEDLINE | ID: mdl-39269073

RESUMEN

In recent years, the development of environmentally friendly, lead-free ferroelectric films with prominent electrostrictive effects have been a key area of focus due to their potential applications in micro-actuators, sensors, and transducers for advanced microelectromechanical systems (MEMS). This work investigated the enhanced electrostrictive effect in lead-free sodium bismuth titanate-based relaxor ferroelectric films. The films, composed of (Bi0.5Na0.5)0.8-xBaxSr0.2TiO3 (BNBST, x = 0.02, 0.06, and 0.11), with thickness around 1 µm, were prepared using a sol-gel method on Pt/TiO2/SiO2/Si substrates. By varying the Ba2+ content, the crystal structure, morphology, and electrical properties, including dielectric, ferroelectric, strain, and electromechanical performance, were investigated. The films exhibited a single pseudocubic structure without preferred orientation. A remarkable strain response (S > 0.24%) was obtained in the films (x = 0.02, 0.06) with the coexistence of nonergodic and ergodic relaxor phases. Further, in the x = 0.11 thick films with an ergodic relaxor state, an ultrahigh electrostrictive coefficient Q of 0.32 m4/C2 was achieved. These findings highlight the potential of BNBST films as high-performance, environmentally friendly electrostrictive films for advanced microelectromechanical systems (MEMS) and electronic devices.

6.
J Environ Manage ; 369: 122364, 2024 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-39236610

RESUMEN

Influence of climate change on the geospatial heterogeneity in agricultural production remains poorly understood. In this study, heterogeneity in climate's impacts on wheat production across the North China Plain (NCP) was explored by integrating APSIM model, process-based factor-control quantitative approach, and geostatistical analyses. The results indicated that increased precipitation and minimum temperature boosted yields, while elevated maximum temperature and reduced radiation exerted adverse effects. The most pronounced negative impact arose from the coupling variation between maximum temperature and radiation, contributing to yields' variations of -5.84% from 2000 to 2010 and -5.22% from 2010 to 2020. In last two decades, climate change has augmented the overall geospatial heterogeneity degree in wheat yields. The chief factor contributing to yields' heterogeneity was the maximum temperature during anthesis-maturation stage, explaining an average of 37.6% of yields' heterogeneity, followed by precipitation throughout the whole growth period and the anthesis-maturation stage, explaining 36.1% and 34.5% respectively. A reciprocal enhancement mechanism exists between factors in driving yields' heterogeneity. Wheat yields in the southwestern NCP benefited more from increased precipitation and minimum temperature. Between 2000 and 2010, yields in the central NCP (junctions of Henan, Hebei, and Shandong) experienced the most pronounced adverse impact from increased maximum temperature. However, by 2010-2020, significant adverse impact shifted to western NCP, expanding spatially. During 2010-2020, the geospatial scope of radiation's significant negative impact expanded compared to the preceding decade, particularly affecting the yields in central and eastern NCP. The identified geospatial heterogeneity pattern of climate's impacts can guide spatially-matched climate-adaptive management adjustments. For instance, intensifying the defense against high-temperature's impacts in northwestern Henan, southern Hebei, and western Shandong, while improving the adaptation to radiation reduction in the central and eastern NCP. The findings are expected to advance regional-scale climate-smart agricultural development.


Asunto(s)
Agricultura , Cambio Climático , Triticum , Triticum/crecimiento & desarrollo , China , Temperatura , Clima
7.
Sensors (Basel) ; 24(17)2024 Aug 27.
Artículo en Inglés | MEDLINE | ID: mdl-39275451

RESUMEN

A MEMS piezoresistive sensor for measuring accelerations greater than 100,000 g (about 106 m/s2) is described in this work. To enhance the performance of the sensor, specifically widening its measurement range and natural frequency, a cross-beam construction with a center block was devised, and a Wheatstone bridge was formed by placing four piezoresistors at the ends of the fixed beams to convert acceleration into electricity. The location of the varistor was determined using the finite element approach, which yielded the optimal sensitivity. Additionally, a reliable Pt-Ti-Pt-Au electrode was designed to solve the issue of the electrode failing under high impact and enhancing the stability of the ohmic contact. The accelerometer was fabricated using MEMS technology, and the experiment with a Hopkinson pressure bar and hammering was conducted, and the bias stability was measured. It had a sensitivity of 1.06 µV/g with good linearity. The simulated natural frequency was 633 kHz The test result revealed that the accelerometer can successfully measure an acceleration of 100,000 g.

8.
Chem Biol Drug Des ; 104(2): e14607, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-39179521

RESUMEN

The process of developing new drugs is widely acknowledged as being time-intensive and requiring substantial financial investment. Despite ongoing efforts to reduce time and expenses in drug development, ensuring medication safety remains an urgent problem. One of the major problems involved in drug development is hepatotoxicity, specifically known as drug-induced liver injury (DILI). The popularity of new drugs often poses a significant barrier during development and frequently leads to their recall after launch. In silico methods have many advantages compared with traditional in vivo and in vitro assays. To establish a more precise and reliable prediction model, it is necessary to utilize an extensive and high-quality database consisting of information on drug molecule properties and structural patterns. In addition, we should also carefully select appropriate molecular descriptors that can be used to accurately depict compound characteristics. The aim of this study was to conduct a comprehensive investigation into the prediction of DILI. First, we conducted a comparative analysis of the physicochemical properties of extensively well-prepared DILI-positive and DILI-negative compounds. Then, we used classic substructure dissection methods to identify structural pattern differences between these two different types of chemical molecules. These findings indicate that it is not feasible to establish property or substructure-based rules for distinguishing between DILI-positive and DILI-negative compounds. Finally, we developed quantitative classification models for predicting DILI using the naïve Bayes classifier (NBC) and recursive partitioning (RP) machine learning techniques. The optimal DILI prediction model was obtained using NBC, which combines 21 physicochemical properties, the VolSurf descriptors and the LCFP_10 fingerprint set. This model achieved a global accuracy (GA) of 0.855 and an area under the curve (AUC) of 0.704 for the training set, while the corresponding values were 0.619 and 0.674 for the test set, respectively. Moreover, indicative substructural fragments favorable or unfavorable for DILI were identified from the best naïve Bayesian classification model. These findings may help prioritize lead compounds in the early stage of drug development pipelines.


Asunto(s)
Enfermedad Hepática Inducida por Sustancias y Drogas , Aprendizaje Automático , Humanos , Preparaciones Farmacéuticas/química , Teorema de Bayes , Simulación por Computador
9.
Front Immunol ; 15: 1423775, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39192984

RESUMEN

Background: Tertiary lymphoid structures (TLS), ordered structure of tumor-infiltrating immune cells in tumor immune microenvironment (TIME), play an important role in the development and anti-tumor immunity of various cancers, including liver, colon, and gastric cancers. Previous studies have demonstrated that the presence of TLS in intra-tumoral (IT), invasive margin (IM), and peri-tumoral (PT) regions of the tumors at various maturity statuses. However, the density of TLS in different regions of non-small cell lung cancer (NSCLC) has not been extensively studied. Methods: TLS and tumor-infiltrating immune cells were assessed using immunohistochemistry (IHC) staining in 82 NSCLC patients. Tumor samples were divided into three subregions as IT, IM and PT regions, and TLS were identified as early/primary TLS (E-TLS) or secondary/follicular TLS (F-TLS). The distribution of TLS in different maturity statuses, along with their correlation with clinicopathological characteristics and prognostic value, was assessed. Nomograms were used to predict the probability of 1-, 3-, and 5-year overall survival (OS) in patients with NSCLC. Results: The density of TLS and proportion of F-TLS in the IT region (90.2%, 0.45/mm2, and 61.0%, respectively) were significantly higher than those in the IM region (72.0%, 0.18/mm2, and 39.0%, respectively) and PT region (67.1%, 0.16/mm2, and 40.2%, respectively). A lower density of TLS, especially E-TLS in the IM region, was correlated with better prognosis in NSCLC patients. CD20+ B cells, CD3+ T cells, CD8+ cytotoxic T cells, and CD68+ macrophages were significantly overexpressed in the IM region. CD20+ B cells and CD3+ T cells in the IM region were significantly correlated with the density of E-TLS, while no statistically significant correlation was found with F-TLS. The E-TLS density in the IM region and TNM stage were independent prognostic factors for NSCLC patients. The nomogram showed good prognostic ability. Conclusions: A higher density of E-TLS in the IM region was associated with a worse prognosis in NSCLC patients, potentially due to the inhibition of TLS maturation caused by the increased density of suppressive immune cells at the tumor invasion front.


Asunto(s)
Carcinoma de Pulmón de Células no Pequeñas , Neoplasias Pulmonares , Linfocitos Infiltrantes de Tumor , Estructuras Linfoides Terciarias , Microambiente Tumoral , Humanos , Carcinoma de Pulmón de Células no Pequeñas/inmunología , Carcinoma de Pulmón de Células no Pequeñas/mortalidad , Carcinoma de Pulmón de Células no Pequeñas/patología , Estructuras Linfoides Terciarias/inmunología , Estructuras Linfoides Terciarias/patología , Masculino , Femenino , Neoplasias Pulmonares/inmunología , Neoplasias Pulmonares/patología , Neoplasias Pulmonares/mortalidad , Persona de Mediana Edad , Pronóstico , Anciano , Microambiente Tumoral/inmunología , Linfocitos Infiltrantes de Tumor/inmunología , Adulto
10.
Adv Sci (Weinh) ; 11(33): e2404272, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-38953411

RESUMEN

The phenomenon of flexoelectricity, wherein mechanical deformation induces alterations in the electron configuration of metal oxides, has emerged as a promising avenue for regulating electron transport. Leveraging this mechanism, stress sensing can be optimized through precise modulation of electron transport. In this study, the electron transport in 2D ultra-smooth In2O3 crystals is modulated via flexoelectricity. By subjecting cubic In2O3 (c-In2O3) crystals to significant strain gradients using an atomic force microscope (AFM) tip, the crystal symmetry is broken, resulting in the separation of positive and negative charge centers. Upon applying nano-scale stress up to 100 nN, the output voltage and power values reach their maximum, e.g. 2.2 mV and 0.2 pW, respectively. The flexoelectric coefficient and flexocoupling coefficient of c-In2O3 are determined as ≈0.49 nC m-1 and 0.4 V, respectively. More importantly, the sensitivity of the nano-stress sensor upon c-In2O3 flexoelectric effect reaches 20 nN, which is four to six orders smaller than that fabricated with other low dimensional materials based on the piezoresistive, capacitive, and piezoelectric effect. Such a deformation-induced polarization modulates the band structure of c-In2O3, significantly reducing the Schottky barrier height (SBH), thereby regulating its electron transport. This finding highlights the potential of flexoelectricity in enabling high-performance nano-stress sensing through precise control of electron transport.

11.
Mol Neurobiol ; 2024 Jul 04.
Artículo en Inglés | MEDLINE | ID: mdl-38963532

RESUMEN

The comorbidity of anxiety and depression frequently occurs in patients with neuropathic pain. The ventrolateral orbital cortex (VLO) plays a critical role in mediating neuropathic pain and anxiodepression in rodents. Previous studies suggested that 5-HT6 receptors in the VLO are involved in neuropathic pain. Strong evidence supports a close link between 5-HT6 receptors and affective disorders such as depression and anxiety disorders. However, it remains unclear whether the 5-HT6 receptors in the VLO are involved in neuropathic pain-induced anxiodepression. Using a rat neuropathic pain model of spared nerve injury (SNI), we demonstrated that rats exhibited significant anxiodepression-like behaviors and the expression of VLO 5-HT6 receptors obviously decreased four weeks after SNI surgery. Microinjection of the 5-HT6 receptor agonist EMD-386088 into the VLO or overexpression of VLO 5-HT6 receptors alleviated anxiodepression-like behaviors. These effects were blocked by pre-microinjection of a selective 5-HT6 receptor antagonist (SB-258585) or inhibitors of AC (SQ-22536), PKA (H89), and MEK1/2 (U0126) respectively. Meanwhile, the expression of p-ERK, p-CREB, and BDNF in the VLO decreased four weeks after SNI surgery. Furthermore, administration of EMD-386088 upregulated the expression of BDNF, p-ERK, and p-CREB in the VLO of SNI rats, which were reversed by pre-injection of SB-258585. These findings suggest that activating 5-HT6 receptors in the VLO has anti-anxiodepressive effects in rats with neuropathic pain via activating AC-cAMP-PKA-MERK-CREB-BDNF signaling pathway. Accordingly, 5-HT6 receptor in the VLO could be a potential target for the treatment of the comorbidity of neuropathic pain and anxiodepression.

12.
Virology ; 596: 110124, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38838475

RESUMEN

While mammals can be infected by influenza A virus either sporadically or with well adapted lineages, aquatic birds are the natural reservoir of the pathogen. So far most of the knowledge on influenza virus dynamics was however gained on mammalian models. In this study, we infected turkeys using a low pathogenic avian influenza virus and determined the infection dynamics with a target-cell limited model. Results showed that turkeys had a different set of infection characteristics, compared with humans and ponies. The viral clearance rates were similar between turkeys and ponies but higher than that in humans. The cell death rates and cell to cell transmission rates were similar between turkeys and humans but higher than those in ponies. Overall, this study indicated the variations of within-host dynamics of influenza infection in avian, humans, and other mammalian systems.


Asunto(s)
Subtipo H9N2 del Virus de la Influenza A , Gripe Aviar , Pavos , Animales , Pavos/virología , Gripe Aviar/virología , Gripe Aviar/transmisión , Subtipo H9N2 del Virus de la Influenza A/genética , Subtipo H9N2 del Virus de la Influenza A/patogenicidad , Subtipo H9N2 del Virus de la Influenza A/fisiología , Humanos , Caballos , Infecciones por Orthomyxoviridae/virología , Infecciones por Orthomyxoviridae/veterinaria , Infecciones por Orthomyxoviridae/transmisión , Gripe Humana/virología
13.
J Proteome Res ; 23(7): 2376-2385, 2024 Jul 05.
Artículo en Inglés | MEDLINE | ID: mdl-38856018

RESUMEN

Schizophrenia is a severe psychological disorder. The current diagnosis mainly relies on clinical symptoms and lacks laboratory evidence, which makes it very difficult to make an accurate diagnosis especially at an early stage. Plasma protein profiles of schizophrenia patients were obtained and compared with healthy controls using 4D-DIA proteomics technology. Furthermore, 79 DEPs were identified between schizophrenia and healthy controls. GO functional analysis indicated that DEPs were predominantly associated with responses to toxic substances and platelet aggregation, suggesting the presence of metabolic and immune dysregulation in patients with schizophrenia. KEGG pathway enrichment analysis revealed that DEPs were primarily enriched in the chemokine signaling pathway and cytokine receptor interactions. A diagnostic model was ultimately established, comprising three proteins, namely, PFN1, GAPDH and ACTBL2. This model demonstrated an AUC value of 0.972, indicating its effectiveness in accurately identifying schizophrenia. PFN1, GAPDH and ACTBL2 exhibit potential as biomarkers for the early detection of schizophrenia. The findings of our studies provide novel insights into the laboratory-based diagnosis of schizophrenia.


Asunto(s)
Biomarcadores , Profilinas , Proteómica , Esquizofrenia , Esquizofrenia/metabolismo , Esquizofrenia/diagnóstico , Esquizofrenia/sangre , Humanos , Biomarcadores/sangre , Biomarcadores/metabolismo , Proteómica/métodos , Profilinas/metabolismo , Femenino , Masculino , Adulto , Estudios de Casos y Controles , Gliceraldehído-3-Fosfato Deshidrogenasa (Fosforilante)/metabolismo , Persona de Mediana Edad , Proteínas Sanguíneas/análisis , Proteoma/análisis
14.
Transl Cancer Res ; 13(4): 2043-2063, 2024 Apr 30.
Artículo en Inglés | MEDLINE | ID: mdl-38737692

RESUMEN

Background and Objective: With advances in gut microbiome research, it has been recognized that the gut microbiome has an important and far-reaching impact on many human diseases, including cancer. Therefore, more and more researchers are focusing on the treatment of gut flora in tumors. In this article, we present a review of the mechanisms of gut microbes in tumor immunotherapy and related studies to provide reference for further research and insights into the clinical application of gut microbes. Methods: Between April 25, 2023, and November 25, 2023, we searched for articles published only in English between 1984 and 2023 using the databases PubMed, American Medical Association and Elsevier ScienceDirect using the keywords "gut microbiology" and "tumor" or "immunotherapy". Key Content and Findings: The gastrointestinal tract contains the largest number of microorganisms in the human body. Microorganisms are involved in regulating many physiological activities of the body. Studies have shown that gut microbes and their derivatives are involved in the occurrence and development of a variety of inflammations and tumors, and changes in their abundance and proportion affect the degree of cancer progression and sensitivity to immunotherapy. Gut microbiota-based drug research is ongoing, and some anti-tumor studies have entered the clinical trial stage. Conclusions: The abundance and proportion of intestinal microorganisms influence the susceptibility of tumors to tumor immunotherapy. This article reviewed the effects and mechanisms of gut microbes on tumor immunotherapy to further explore the medical value of gut microbes in tumor immunotherapy.

15.
China CDC Wkly ; 6(17): 378-382, 2024 Apr 26.
Artículo en Inglés | MEDLINE | ID: mdl-38737824

RESUMEN

Introduction: Laiza and nearby areas (LNA) in Myanmar are identified as the primary malaria hotspots in the bordering regions of Yunnan Province, China. Methods: Six sentinel surveillance sites were established at the China-Myanmar border in LNA to monitor malaria. Data from 2019 was used as a baseline to analyze malaria incidence and trends in LNA and Myanmar, as well as the importation of malaria cases into China from 2019 to 2023. Results: Plasmodium vivax was the predominant species, representing 99.95% (14,060/14,066) of confirmed malaria cases in LNA. A total of 8,356 malaria cases were identified in 2023, with an annual parasite incidence (API) of 19.78 per 100 person-years. Compared to 2019, the incidence rate ratio was 21.47 (95% confidence interval: 18.84, 24.48), indicating that the API in 2023 was 21.47 times higher than that in 2019. In Yunnan, out of 1,016 reported cases, 545 imported cases (53.64%) originated from LNA and spread to 18 (13.95%) out of 129 counties. Ten provinces in China, including Yunnan, reported imported malaria cases from LNA in Myanmar. Conclusions: The increase in population, particularly among internally displaced persons, along with inadequate healthcare services, has led to a notable resurgence of malaria in LNA. This resurgence poses a risk to preventing the re-emergence of malaria transmission in China. There is an urgent need for novel collaborative policies, as well as financial and technical assistance, to enhance malaria control efforts in LNA, Myanmar.

16.
Sci Rep ; 14(1): 11362, 2024 May 18.
Artículo en Inglés | MEDLINE | ID: mdl-38762613

RESUMEN

Topographic Rossby waves (TRWs) dominate the low-frequency variability of deep ocean currents and play a crucial role in energy exchange and material mixing. On the continental slope of the southwestern South China Sea, a deep-water mooring was deployed to observe TRWs for a period of ~ 40 days. The TRWs, with a wavelength of 109 km, account for 41.3% of the subinertial variations. A ray-tracing model was applied to investigate the propagation and energy source. The results showed that the TRWs propagated from the northeast of the mooring location and were most likely caused by the mesoscale eddy disturbances off the Vietnam coast. This study provides a new perspective on examining the impact of mesoscale eddies off Vietnam on abyssal currents.

17.
Chem Commun (Camb) ; 60(41): 5407-5410, 2024 May 16.
Artículo en Inglés | MEDLINE | ID: mdl-38683050

RESUMEN

Visible-light-induced [3+2] cyclization of vinyl azides with perfluoroalkyl-substituted imidoyl sulfoxonium ylides has been developed for the first time. In this transformation, perfluoroalkyl-substituted imidoyl sulfoxonium ylides are firstly employed as a carbon radical precursor under visible light irradiation, providing a new and efficient method for the construction of perfluoroalkyl-substituted 1-pyrrolines.

18.
Rev Sci Instrum ; 95(3)2024 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-38535486

RESUMEN

This paper describes the design, fabrication, and characterization of a quartz vibrating beam accelerometer consisting of a metal spring-mass and quartz double-ended tuning forks (DETFs). In this approach, the inertial force of the proof mass pulls or compresses the DETFs, affecting their resonance frequency and, thus, enabling the quasi-digital measurement of acceleration. An isolation structure was specifically designed to prevent the external interference stress from transforming into the DETFs and to decrease the DETFs' thermal stress as the ambient temperature changes. A stress-free and high-precision wire-cut electrical discharge machining process was introduced to solve the fabrication problem of flexible hinges, and a femtosecond laser was used to release the proof mass, comprehensively considering the compatibility of the fabrication process and structural design. The oscillation excitation and detection of the DETFs were analyzed, and the DETFs were fabricated using a micro-electromechanical systems process. Sensor dimensions were optimized to improve sensor sensitivity. An accelerometer prototype was fabricated, and its performance was characterized. The tested scale factor was 157.28 Hz/g, and its stability was 16.54 ppm. The bias stability and 1 g stability at 1 h were 18 and 7.84 µg, respectively. The experimental results validated the feasibility of the sensor design.

19.
Environ Sci Pollut Res Int ; 31(19): 28007-28024, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38526715

RESUMEN

The coal's mechanical properties have a significant influence on mining safety and the mine environment. Preparing a standard sample and conducting repeat mechanical testing are challenging because the coal is primarily soft, fragmented, and rich in developed fractures. This study used nanoindentation technology, combined with X-ray diffraction, small-angle X-ray, a high magnification microscope, and mechanical parameter scale-up analysis, to study the micromechanical of three coals being dominated by heterogeneous components and pores. The results show that load-displacement curves with different maximum loads (50 mN, 100 mN, and 200 mN) all appear the pop-in events, and coal heterogeneity affects the frequency of their occurrence. As the maximum load is increased, pop-in event of DSC appears once each, YW increases from zero to three times and HM decreases from four to two times. The heterogeneity of pore structure has little effect on residual displacement, which is mainly affected by hard minerals, and hard minerals reduce the law that residual displacement increases with the increase in maximum load. The micromechanical parameters of soft coals are mainly affected by large pores, while hard coals are mainly affected by hard minerals. The coal's heterogeneity does not affect the linear relationship between hardness and elastic modulus, but stronger heterogeneity will weaken the linear relationship between fracture toughness and elastic modulus. Compared to the mechanical parameters after scale-up, the values obtained based on nanoindentation are less than 15.588% larger, and the increase in the heterogeneity and hard minerals can make the predicted parameters more accurate. The nanoindentation technique can not only provide an efficient and accurate method for studying the mechanical properties of heterogeneous coal at the nanoscale, an important guide for large-scale coal.


Asunto(s)
Carbón Mineral , Minerales , Minerales/química , Difracción de Rayos X
20.
Heliyon ; 10(3): e25825, 2024 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-38356543

RESUMEN

The association between clay minerals and organic carbon is pivotal for understanding transport, burial, and preservation processes of sedimentary organic carbon. However, fine-scale microscopic studies are still limited in assessing the effect of diverse clay mineral structures and properties on organic carbon sequestration. In this study, we employed X-ray photoelectron spectroscopy, Fourier transform infrared spectroscopy, and transmission electron microscopy coupled with energy dispersive spectroscopy and electron energy loss spectroscopy analyses to investigate the nanoscale interaction between clay minerals and organic carbon of two typical fluvial sediment samples with contrasting clay mineral compositions and organic carbon origins. Sample from Taiwan shows abundant illite and chlorite with petrogenic organic carbon, while sample from Luzon has significant smectite with pedogenic organic carbon. We observed that the nanostructure of the clay minerals controls the distribution of organic carbon. In the Luzon sample, the organic carbon is tightly associated with smectite, occupying expandable interlayer spaces. In the Taiwan sample, however, the organic carbon is primarily confined on the surface and edge of illite. These findings offer valuable insights into the selective association of organic carbon with clay minerals and underscore the role of clay mineral nanolayer structures in governing the occurrence and preservation of organic carbon in sediments. A comprehensive understanding of these interactions is crucial for accurate assessments of carbon cycling and sequestration in the natural environment.

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