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1.
Environ Pollut ; : 124482, 2024 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-38960118

RESUMEN

Pharmaceutical plant sites play a significant role in the dissemination of antibiotic resistance genes (ARGs) into the environment. It is imperative to comprehensively monitor of ARGs across various environmental media at these sites. This study focused on three pharmaceutical plants, two located in North China and one in South China. Through metagenomic approaches, we examined the composition, mobility potential, and bacterial hosts of ARGs in diverse media such as process water, groundwater, topsoil, soil cores, and pharmaceutical fermentation residues across diverse environmental matrices, including topsoil, soil cores, process water, groundwater, and pharmaceutical fermentation residues. We identified a wide array of ARGs, comprising 21 types and 740 subtypes, with process water exhibiting the highest abundance and diversity. Treatment processes varied in their efficacy in eliminating ARGs, and the clinically relevant ARGs should also be considered when evaluating wastewater treatment plant efficiency. Geographical distinctions in groundwater ARG distribution between northern and southern regions were observed. Soil samples from the three sites showed minimal impact from pharmaceutical activity, with vancomycin-resistance genes being the most prevalent. High levels of ARGs in pharmaceutical fermentation residues underscore the necessity for improved waste management practices. Metagenomic assembly revealed that plasmid-mediated ARGs were more abundant than chromosome-mediated ARGs. Metagenome-assembled genomes (MAGs) analysis identified 166 MAGs, with 62 harboring multiple ARGs. Certain bacteria tended to carry specific types of ARGs, revealing distinct host-resistance associations. This study enhances our understanding of ARG dissemination across different environmental media within pharmaceutical plants and underscores the importance of implementing strict regulations for effluent and residue discharge to control ARG spread.

2.
Chem Commun (Camb) ; 2024 Jul 12.
Artículo en Inglés | MEDLINE | ID: mdl-38993133

RESUMEN

Electrochemical hydrocarboxylation of enol acetates with CO2 is developed. The disclosed process provides ß-acetoxycarboxylic acids in 25-66% yields, in contrast to the electrolysis of ketones, silyl enol ethers and vinyl tosylates with CO2, which leads mainly to alcohols.

3.
Foods ; 13(11)2024 May 30.
Artículo en Inglés | MEDLINE | ID: mdl-38890947

RESUMEN

This study aimed to investigate the efficacy of supercritical CO2 (SC-CO2) extraction in enhancing the extraction rate, purity, and antioxidant activity of Indocalamus latifolius (Keng) McClure (Poaceae) leaf terpenoids (ILLTs). Crude extracts obtained from leaves were subjected to qualitative and quantitative analyses, revealing neophytadiene, phytol, ß-sitosterol, ß-amyrone, squalene, and friedelin as the primary terpenoid constituents, identified through gas chromatography-mass spectrometry (GC-MS). Compared with steam distillation extraction (SD), simultaneous distillation extraction (SDE), ultra-high pressure-assisted n-hexane extraction (UHPE-Hex), ultra-high pressure-assisted ethanol extraction (UHPE-EtOH), ultrasound-assisted n-hexane extraction (UE-Hex), and ultrasound-assisted ethanol extraction (UE-EtOH), SC-CO2 exhibited a superior ILLT extraction rate, purity, and antioxidant activity. Scanning electron microscopy (SEM) observations of the residues further revealed more severe damage to both the residues and their cell walls after SC-CO2 extraction. Under optimal parameters (4.5 h, 26 MPa, 39 °C, and 20% ethyl alcohol), the ILLT extraction rate with SC-CO2 reached 1.44 ± 0.12 mg/g, which was significantly higher than the rates obtained by the other six methods. The subsequent separation and purification using WelFlash C18-l, BUCHI-C18, and Sephadex LH-20 led to an increase in the purity of the six terpenoid components from 12.91% to 93.34%. Furthermore, the ILLTs demonstrated cytotoxicity against HepG2 cells with an IC50 value of 148.93 ± 9.93 µg/mL. Additionally, with increasing concentrations, the ILLTs exhibited an enhanced cellular antioxidant status, as evidenced by reductions in both reactive oxygen species (ROS) and malondialdehyde (MDA) levels.

4.
Sci Rep ; 14(1): 13050, 2024 06 06.
Artículo en Inglés | MEDLINE | ID: mdl-38844812

RESUMEN

This study introduces a novel approach for synthesizing a Cu(II)-based coordination polymer (CP), {[Cu(L)(4,4´-OBA)]·H2O}n (1), using a mixed ligand method. The CP was successfully prepared by reacting Cu(NO3)2·3H2O with the ligand 3,6-bis(benzimidazol-1-yl)pyridazine in the presence of 4,4´-H2OBA, demonstrating an innovative synthesis strategy. Furthermore, a novel hydrogel composed of hyaluronic acid (HA) and carboxymethyl chitosan (CMCS) with a porous structure was developed for drug delivery purposes. This hydrogel facilitates the encapsulation of CP1, and enables the loading of paclitaxel onto the composite to form HA/CMCS-CP1@paclitaxel. In vitro cell experiments demonstrated the promising modulation of thyroid cancer biomarker genes S100A6 and ARID1A by HA/CMCS-CP1@paclitaxel. Finally, reinforcement learning simulations were employed to optimize novel metal-organic frameworks, underscoring the innovative contributions of this study.


Asunto(s)
Cobre , Hidrogeles , Paclitaxel , Neoplasias de la Tiroides , Paclitaxel/química , Paclitaxel/farmacología , Cobre/química , Hidrogeles/química , Humanos , Neoplasias de la Tiroides/tratamiento farmacológico , Neoplasias de la Tiroides/patología , Quitosano/química , Quitosano/análogos & derivados , Línea Celular Tumoral , Ácido Hialurónico/química , Complejos de Coordinación/química , Complejos de Coordinación/farmacología , Portadores de Fármacos/química , Estructuras Metalorgánicas/química , Estructuras Metalorgánicas/farmacología
5.
Sci Total Environ ; 946: 174227, 2024 Jun 25.
Artículo en Inglés | MEDLINE | ID: mdl-38936710

RESUMEN

The use of observation-dependent methods for crop productivity and food security assessment is challenging in data-sparse regions. This study presents a transferable framework and applies it to North Korea (NK) to assess rice productivity based on climate similarity, transferable machine-learning techniques, and extendable multi-source data. We initially divided the primary phenological stages of rice in the study region and extracted dynamic rice distributions based on Moderate Resolution Imaging Spectroradiometer products and phenological observations. We compared the performances of four representative environmentally driven models (Linear Regression, back-propagation Neural Network, Support Vector Machine, and Random Forest) in simulating rice productivity using an extensive dataset that included multi-angle vegetation monitoring, climate variables, and planting distribution information. The framework integrated an optimal environmentally driven model with agricultural management practices for transferability to predict rice productivity in NK over multiple years. Additionally, two crop growth scenarios (whole growth period (WGP) and seeding-heading period (SHP)) were compared to assess pre-harvest forecasting capabilities and identify dominant factors. Finally, independent datasets from the Food and Agriculture Organization, World Food Program, and Global Gridded Crop Models were used to validate the magnitude and spatial distribution of the predicted results. The results showed that phenological identification based on remote sensing can accurately capture rice growth characteristics and map rice distribution. Random Forest outperformed other models in simulating rice productivity variation, with r-squares of 0.87 and 0.83 in the WGP and SHP, respectively. The solar-induced chlorophyll fluorescence, maximum temperature, and evapotranspiration collectively determined approximately 40 % of the variation in yield simulated using Random Forest. Conversely, planting areas contributed over 42 % of the variation in rice production. Compared to Food and Agriculture Organization statistics, the environmentally driven framework explained 78.72 % and 76.89 % of the production variation and 69.42 % and 71.15 % of the yield variation in NK under the WGP and SHP, respectively. Moreover, the environmental management-driven framework captured over 90 % of the yield variation. The predicted spatial pattern of rice productivity exhibited significant concordance with the World Food Program and Global Gridded Crop Model reports. In summary, the proposed transferable framework for crop productivity assessment contributes to early warnings of production reduction and has the potential for scalability across various crops and data-sparse regions.

6.
Nanoscale ; 16(26): 12586-12598, 2024 Jul 04.
Artículo en Inglés | MEDLINE | ID: mdl-38869377

RESUMEN

In situ monitoring of H2O2 in cellular microenvironments plays a critical role in the early diagnosis and pretreatment of cancer, but is limited by the lack of efficient and low-cost strategies for the large-scale preparation of real-time biosensors. Herein, a universal strategy for MXene-based composite inks combined with a scalable screen-printing process is validated in large-scale manufacturing of electrochemical biosensors for in situ detection of H2O2 secreted from live cells. Compositing biocompatible carboxymethyl cellulose (CMCS) with excellent conductive MXene, a water-based ink electrode (MXene/CMCS) with tunable viscosity is efficiently printed with desirable printing accuracy. Subsequently, the MXene/CMCS@HRP electrochemical biosensor exhibits stable electrochemical performance through HRP nanoflower modification, showing rapid electron transport and high electrocatalytic capacity, and demonstrating a low limit of detection (0.29 µM) with a wide linear detection range (0.5 µM-3 mM), superior sensitivity (56.45 µA mM-1 cm-2), long-term stability and high anti-interference ability. Moreover, this electrochemical biosensor is effectively employed for in situ detection of H2O2 secreted from HeLa cells, revealing good biocompatibility and outstanding biosensing capability. This proposed strategy not only extends the possibility of low-cost biomedical devices, but also provides a promising approach for early diagnosis and treatment of cancer.


Asunto(s)
Técnicas Biosensibles , Técnicas Electroquímicas , Electrodos , Peróxido de Hidrógeno , Técnicas Biosensibles/métodos , Peróxido de Hidrógeno/análisis , Humanos , Células HeLa , Carboximetilcelulosa de Sodio/química , Límite de Detección , Neoplasias/diagnóstico
7.
Int J Biol Macromol ; 273(Pt 2): 133135, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38876231

RESUMEN

Largemouth bass (Micropterus salmoides) has emerged as a significant economic fish species, with a rise in Aeromonas veronii infections in farming. However, research on adjuvants for vaccines against A. veronii in largemouth bass remains scarce. In present study, recombinant largemouth bass IL-1ß (LbIL-1ß) was expressed to explore its adjuvant effect on the A. veronii inactivated vaccine. Following vaccination with recombinant LbIL-1ß (rLbIL-1ß) and the inactivated A. veronii, higher serum SOD levels and lysozyme activities were observed in largemouth bass from inactivated A. veronii + rLbIL-1ß vaccinated group. Furthermore, it was discovered that rLbIL-1ß was able to boost the serum-specific antibody levels induced by the inactivated A. veronii. The qRT-PCR analysis revealed that rLbIL-1ß also enhanced the expression of IgM, CD4, and MHC II in largemouth bass triggered by the inactivated A. veronii. After challenged with live A. veronii, the outcomes demonstrated that the relative percentage survival (RPS) for largemouth bass resulting from the inactivated A. veronii in combination with rLbIL-1ß was 76.67 %, surpassing the RPS of 60 % in the inactivated A. veronii group. Collectively, these findings indicate that rLbIL-1ß enhances the protective effect of the A. veronii inactivated vaccine on largemouth bass, showcasing potential as an adjuvant for further development.


Asunto(s)
Adyuvantes Inmunológicos , Aeromonas veronii , Vacunas Bacterianas , Lubina , Enfermedades de los Peces , Interleucina-1beta , Vacunas de Productos Inactivados , Animales , Aeromonas veronii/inmunología , Vacunas Bacterianas/inmunología , Lubina/inmunología , Lubina/microbiología , Enfermedades de los Peces/inmunología , Enfermedades de los Peces/prevención & control , Enfermedades de los Peces/microbiología , Infecciones por Bacterias Gramnegativas/inmunología , Infecciones por Bacterias Gramnegativas/veterinaria , Infecciones por Bacterias Gramnegativas/prevención & control , Vacunación , Vacunas de Productos Inactivados/inmunología
9.
Molecules ; 29(11)2024 Jun 03.
Artículo en Inglés | MEDLINE | ID: mdl-38893498

RESUMEN

Due to the high content of impurities such as proteins in tamarind seed polysaccharide (TSP), they must be separated and purified before it can be used. TSP can disperse in cold water, but a solution can only be obtained by heating the mixture. Therefore, it is important to understand the dispersion and dissolution process of TSP at different temperatures to expand the application of TSP. In this study, pasting behavior and rheological properties as a function of temperature were characterized in comparison with potato starch (PS), and their relationship with TSP molecular features and microstructure was revealed. Pasting behavior showed that TSP had higher peak viscosity and stronger thermal stability than PS. Rheological properties exhibited that G' and G'' of TSP gradually increased with the increase in temperature, without exhibiting typical starch gelatinization behavior. The crystalline or amorphous structure of TSP and starch was disrupted under different temperature treatment conditions. The SEM results show that TSP particles directly transformed into fragments with the temperature increase, while PS granules first expanded and then broken down into fragments. Therefore, TSP and PS underwent different dispersion mechanisms during the dissolution process: As the temperature gradually increased, TSP possibly underwent a straightforward dispersion and was then dissolved in aqueous solution, while PS granules initially expanded, followed by disintegration and dispersion.


Asunto(s)
Polisacáridos , Reología , Semillas , Almidón , Tamarindus , Temperatura , Tamarindus/química , Polisacáridos/química , Semillas/química , Viscosidad , Almidón/química , Fenómenos Químicos
10.
Sensors (Basel) ; 24(11)2024 Jun 04.
Artículo en Inglés | MEDLINE | ID: mdl-38894418

RESUMEN

Metal-oxide-based gas sensors are extensively utilized across various domains due to their cost-effectiveness, facile fabrication, and compatibility with microelectronic technologies. The copper (Cu)-based multifunctional polymer-enhanced sensor (CuMPES) represents a notably tailored design for non-invasive environmental monitoring, particularly for detecting diverse gases with a low concentration. In this investigation, the Cu-CuO/PEDOT nanocomposite was synthesized via a straightforward chemical oxidation and vapor-phase polymerization. Comprehensive characterizations employing X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM), X-ray diffraction (XRD), and micro Raman elucidated the composition, morphology, and crystal structure of this nanocomposite. Gas-sensing assessments of this CuMPES based on Cu-CuO/PEDOT revealed that the response current of the microneedle-type CuMPES surpassed that of the pure Cu microsensor by nearly threefold. The electrical conductivity and surface reactivity are enhanced by poly (3,4-ethylenedioxythiophene) (PEDOT) polymerized on the CuO-coated surface, resulting in an enhanced sensor performance with an ultra-fast response/recovery of 0.3/0.5 s.

11.
J Sci Food Agric ; 2024 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-38747177

RESUMEN

BACKGROUND: To improve phytol bioavailability, a novel method of magnetic stirring and high-pressure homogenization (HPH) combination was used to prepare zein/fucoidan-coated phytol nanoliposomes (P-NL-ZF). The characterization, the simulated in vitro digestion, and the antioxidant activity of these phytol nanoliposomes from the different processes have been studied. RESULTS: Based on the results of dynamic light scattering (DLS) and gas chromatography-mass spectrometer (GC-MS) analysis, P-NL-ZF prepared through the combination of magnetic stirring and HPH exhibited superior encapsulation efficiency at 76.19% and demonstrated exceptional physicochemical stability under a series of conditions, including storage, pH, and ionic in comparison to single method. It was further confirmed that P-NL-ZF by magnetic stirring and HPH displayed a uniform distribution and regular shape through transmission electron microscopy (TEM). Fourier-transform infrared (FTIR) spectroscopy and differential scanning calorimetry (DSC) analysis showed that electrostatic interactions and hydrogen bonding were the primary driving forces for the formation of composite nanoliposomes. Additionally, an in vitro digestion study revealed that multilayer composite nanoliposomes displayed significant and favorable slow-release properties (58.21%) under gastrointestinal conditions compared with traditional nanoliposomes (82.36%) and free phytol (89.73%). The assessments of chemical and cell-based antioxidant activities demonstrated that the coating of zein/fucoidan on phytol nanoliposomes resulted in enhanced effectiveness in scavenging activity of ABTS free radical and hydroxyl radical and mitigating oxidative damage to HepG2 cells. CONCLUSION: Based on our studies, the promising delivery carrier of zein/fucoidan-coated nanoliposomes is contributed to the encapsulation of hydrophobic natural products and enhancement of their biological activity. © 2024 Society of Chemical Industry.

12.
ChemSusChem ; : e202400608, 2024 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-38747335

RESUMEN

A Cu/Co tandem catalysis protocol was developed to conduct the hydroformylation of olefins using CO2/H2 and PMHS (polymethylhydrosiloxane) as a readily available and environmentally friendly hydride source. This methodology was performed via a two-step approach consisting of the copper-catalyzed reduction of CO2 by hydrosilane and subsequent cobalt-promoted hydroformylation with H2 and the in situ formed CO. The optimized triphos oxide ligand, which presumably facilitates the migratory insertion of CO gives moderate to excellent yields for both terminal and internal alkenes. This earth-abundant metal catalysis provides a reliable and efficient way to afford useful aldehydes in industry using silicon by-product PMHS as hydrogen source and renewable CO2 as carbonyl source.

13.
Chem Sci ; 15(18): 6833-6841, 2024 May 08.
Artículo en Inglés | MEDLINE | ID: mdl-38725503

RESUMEN

The understanding of electron transfer pathways and orbital interactions between analytes and adsorption sites in gas-sensitive studies, especially at the atomic level, is currently limited. Herein, we have designed eight isoreticular catechol-metalloporphyrin scaffolds, FeTCP-M and InTCP-M (TCP = 5,10,15,20-tetrakis-catechol-porphyrin, M = Fe, Co, Ni and Zn) with adjustable charge transfer schemes in the coordination microenvironment and precise tuning of orbital interactions between analytes and adsorption sites, which can be used as models for exploring the influence of these factors on gas sensing. Our experimental findings indicate that the sensitivity and selectivity can be modulated using the type of metals in the metal-catechol chains (which regulate the electron transfer routes) and the metalloporphyrin rings (which fine-tune the orbital interactions between analytes and adsorption sites). Among the isostructures, InTCP-Co demonstrates the highest response and selectivity to NO2 under visible light irradiation, which could be attributed to the more favorable transfer pathway of charge carriers in the coordination microenvironment under visible light illumination, as well as the better electron spin state compatibility, higher orbital overlap and orbital symmetry matching between the N-2s2pz hybrid orbital of NO2 and the Co-3dz2 orbital of InTCP-Co.

14.
Plants (Basel) ; 13(10)2024 May 17.
Artículo en Inglés | MEDLINE | ID: mdl-38794473

RESUMEN

With the changing global climate, drought stress will pose a considerable challenge to the sustainable development of agriculture in arid regions. The objective of this study was to explore the resistance and water demand of cotton plants to water stress during the flowering and boll setting stage. The experimental plot was in Huaxing Farm of Changji city. The plots were irrigated, respectively, at 100% (as the control), 90%, 85% and 80% of the general irrigation amount in the local area. The relationship between the various measured indexes and final yield under different deficit irrigation (DI) treatments was studied. The results showed that deficit irrigation impacted the growth and development processes of cotton during the flowering and boll setting stage. There was a high negative correlation (R2 > 0.95) between the maximum leaf area index and yield. Similarly, there was a high correlation between malondialdehyde content and yield. Meanwhile, 90% of the local cotton irrigation contributed to water saving and even increasing cotton yield. Furthermore, based on the results, the study made an initial optimization to the local irrigation scheme by utilizing the DSSAT model. It was found that changing the irrigation interval to 12 days during the stage could further enhance cotton yield and conserve resources.

15.
Nat Struct Mol Biol ; 2024 May 29.
Artículo en Inglés | MEDLINE | ID: mdl-38811792

RESUMEN

Dysregulation and enhanced expression of MYC transcription factors (TFs) including MYC and MYCN contribute to the majority of human cancers. For example, MYCN is amplified up to several hundredfold in high-risk neuroblastoma. The resulting overexpression of N-myc aberrantly activates genes that are not activated at low N-myc levels and drives cell proliferation. Whether increasing N-myc levels simply mediates binding to lower-affinity binding sites in the genome or fundamentally changes the activation process remains unclear. One such activation mechanism that could become important above threshold levels of N-myc is the formation of aberrant transcriptional condensates through phase separation. Phase separation has recently been linked to transcriptional regulation, but the extent to which it contributes to gene activation remains an open question. Here we characterized the phase behavior of N-myc and showed that it can form dynamic condensates that have transcriptional hallmarks. We tested the role of phase separation in N-myc-regulated transcription by using a chemogenetic tool that allowed us to compare non-phase-separated and phase-separated conditions at equivalent N-myc levels, both of which showed a strong impact on gene expression compared to no N-myc expression. Interestingly, we discovered that only a small percentage (<3%) of N-myc-regulated genes is further modulated by phase separation but that these events include the activation of key oncogenes and the repression of tumor suppressors. Indeed, phase separation increases cell proliferation, corroborating the biological effects of the transcriptional changes. However, our results also show that >97% of N-myc-regulated genes are not affected by N-myc phase separation, demonstrating that soluble complexes of TFs with the transcriptional machinery are sufficient to activate transcription.

17.
ACS Omega ; 9(13): 15401-15409, 2024 Apr 02.
Artículo en Inglés | MEDLINE | ID: mdl-38585126

RESUMEN

The addition of antioxidants to rubber is one of the most economical and effective methods for delaying rubber aging. However, antioxidant migration can cause environmental pollution. To address this issue, a new reactive antioxidant was synthesized via the chemical bonding of glycidyl methacrylate (GMA) and p-aminodiphenylamine (PPDA). The product was characterized by Fourier-transform infrared spectroscopy, which confirmed the successful reaction between GMA and PPDA, resulting in a compound with the expected structure. The mixture was then combined with a composite of styrene-butadiene rubber and carbon black. The tensile strength, antioxidant properties, migration, and RPA of the resulting materials were tested and compared with those of the commercial antioxidants N-(1,3-dimethylbutyl)-N'-phenyl-p-phenylenediamine, N-isopropyl-N'-phenyl-1,4-phenylenediamine, and poly(1,2-dihydro-2,2,4-trimethylquinoline). After the glycidyl methacrylate antioxidant was grafted onto p-aminodiphenylamine, it became highly compatible with and dispersed in the rubber matrix. The antiaging and antimigration properties of the rubber antioxidants were enhanced without damaging the mechanical properties of the rubber matrix. The short-term and long-term antiaging and antimigration properties of this antioxidant are superior to those of commercially available antioxidants.

18.
Parasit Vectors ; 17(1): 195, 2024 Apr 26.
Artículo en Inglés | MEDLINE | ID: mdl-38671515

RESUMEN

BACKGROUND: Toxoplasma gondii and Neospora caninum are closely related protozoan parasites that are considered important causes of abortion in livestock, causing huge economic losses. Hunan Province ranks 12th in the production of beef and mutton in China. However, limited data are available on the seroprevalence, risk factors and molecular characterization of T. gondii and N. caninum in beef cattle and goats in Hunan province, China. METHODS: Sera of 985 beef cattle and 1147 goats were examined for the presence of specific antibodies against T. gondii using indirect hemagglutination test (IHAT) and anti-N. caninum IgG using competitive-inhibition enzyme-linked immunoassay assay (cELISA). Statistical analysis of possible risk factors was performed using PASW Statistics. Muscle samples of 160 beef cattle and 160 goats were examined for the presence of T. gondii DNA (B1 gene) and N. caninum DNA (Nc-5 gene) by nested PCR. The B1 gene-positive samples were genotyped at 10 genetic markers using the multilocus nested PCR-RFLP (Mn-PCR-RFLP). RESULTS: Specific IgG against T. gondii were detected in 8.3% (82/985) and 13.3% (153/1147) and against N. caninum in 2.1% (21/985) and 2.0% (23/1147) of the beef cattle and goats, respectively. Based on statistical analysis, the presence of cats, semi-intensive management mode and gender were identified as significant risk factors for T. gondii infection in beef cattle. Age was a significant risk factor for T. gondii infection in goats (P < 0.05), and age > 3 years was a significant risk factor for N. caninum infection in beef cattle (P < 0.05). PCR positivity for T. gondii was observed in three beef samples (1.9%; 3/160) and seven chevon samples (4.4%; 7/160). Genotyping of PCR positive samples identified one to be ToxoDB#10. The N. caninum DNA was observed in one beef sample (0.6%; 1/160) but was negative in all chevon samples. CONCLUSIONS: To our knowledge, this is the first large-scale serological and molecular investigation of T. gondii and N. caninum and assessment of related risk factors in beef cattle and goats in Hunan Province, China. The findings provide baseline data for executing prevention and control of these two important parasites in beef cattle and goats in China.


Asunto(s)
Anticuerpos Antiprotozoarios , Enfermedades de los Bovinos , Coccidiosis , Enfermedades de las Cabras , Cabras , Neospora , Toxoplasma , Toxoplasmosis Animal , Animales , Cabras/parasitología , Neospora/genética , Neospora/inmunología , Neospora/aislamiento & purificación , Toxoplasma/genética , Toxoplasma/inmunología , Toxoplasma/aislamiento & purificación , Toxoplasmosis Animal/epidemiología , Toxoplasmosis Animal/parasitología , China/epidemiología , Bovinos , Estudios Seroepidemiológicos , Coccidiosis/veterinaria , Coccidiosis/epidemiología , Coccidiosis/parasitología , Enfermedades de las Cabras/epidemiología , Enfermedades de las Cabras/parasitología , Anticuerpos Antiprotozoarios/sangre , Femenino , Enfermedades de los Bovinos/epidemiología , Enfermedades de los Bovinos/parasitología , Masculino , Factores de Riesgo , Inmunoglobulina G/sangre , ADN Protozoario/genética , Ensayo de Inmunoadsorción Enzimática/veterinaria , Genotipo , Reacción en Cadena de la Polimerasa/veterinaria
19.
Micromachines (Basel) ; 15(4)2024 Apr 17.
Artículo en Inglés | MEDLINE | ID: mdl-38675350

RESUMEN

This study presents a numerical simulation-based investigation of a MEMS (micro-electromechanical systems)technology-based deformable mirror employing a piezoelectric film for fundus examination in adaptive optics. Compared to the classical equal-area electrode arrangement model, we optimize the electrode array for higher-order aberrations. The optimized model centralizes electrodes around the mirror center, which realizes low-voltage driving with high-accuracy correction. The optimized models exhibited commendable correction abilities, achieving a unidirectional displacement of 5.74 µm with a driven voltage of 15 V. The voltage-displacement relationship demonstrated high linearity at 0.99. Furthermore, the deformable mirror's influence matrix was computed, aligning with the Zernike standard surface shape of the order 1-3. To quantify aberration correction capabilities, fitting residuals for both models were calculated. The results indicate an average removal of 96.8% of aberrations to the human eye. This underscores that the optimized model outperforms the classical model in correcting high-order aberrations.

20.
J Org Chem ; 89(8): 5699-5714, 2024 Apr 19.
Artículo en Inglés | MEDLINE | ID: mdl-38564503

RESUMEN

Four heteroatoms dance in the cascade of four pericyclic reactions initiated by ozonolysis of C═N bonds. Switching from imines to semicarbazones introduces the fifth heteroatom that slows this dance, delays reaching the thermodynamically favorable escape path, and allows efficient interception of carbonyl oxides (Criegee intermediates, CIs) by an external nucleophile. The new three-component reaction of alcohols, ozone, and oximes/semicarbazones greatly facilitates synthetic access to monoperoxyacetals (alkoxyhydroperoxides).

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