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Iron-based Fischer-Tropsch synthesis (FTS) catalyst is widely used for syngas conversion, but its iron carbide active phase is easily oxidized into Fe3O4 by the water produced during reaction, leading to the deterioration of catalytic performance. Here, we show an efficient strategy for protecting the iron carbide active phase of FTS catalyst by surface hydrophobization. The hydrophobic surface can reduce the water concentration in the core vicinity of catalyst during syngas conversion, and thus inhibit the oxidation of iron species by water, which enhances the C - C coupling ability of catalyst and promotes the formation of long-chain olefins. More significantly, it is unraveled that appropriate shell thickness plays a crucial role in stabilizing the iron carbide active phase without Fe3O4 formation and achieving good catalytic performance.
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In order to develop antiviral drugs, we utilized pterodontic acid (Poa-1) as a lead compound and conducted various modifications, including oxidation, reduction, addition, esterification, and acylation, resulting in the synthesis of 29 derivatives, of which 25 were novel acylation derivatives. Cell-level validation demonstrated that 4 derivatives exhibited significant inhibitory effects on the influenza A virus (H1N1), with an IC50 = 4.04-36.13 µM. Notably, four acylation derivatives (compounds IIE5, IIE6, IIE9, and IIE17) exhibited specific antiviral activities against influenza A virus (H1N1) with low cytotoxicity, indicating favorable therapeutic indices (SI = 3.5-11.9). Structure-activity relationship studies indicated that C5-C6 olefins are essential groups for antiviral activity, C11-C12 conjugated olefins will not interfere with antiviral activity. Carboxylic acid is an essential group for activity. Moreoverï¼Carboxylic acid acylation can improve antiviral activity, and the inclusion of guanidine, cyclic amine, and phenyl groups with electron-donating substituents could enhance the antiviral activity of the lead compound. Natural products structural modifications are capable of improving the biological activity of lead compounds, offering a rapid pathway for the development of potent new structures.
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Antivirales , Subtipo H1N1 del Virus de la Influenza A , Antivirales/farmacología , Antivirales/síntesis química , Antivirales/química , Relación Estructura-Actividad , Subtipo H1N1 del Virus de la Influenza A/efectos de los fármacos , Estructura Molecular , Acilación , Animales , Perros , Células de Riñón Canino Madin Darby , HumanosRESUMEN
The amyloid-beta peptide (Aß) is the neurotoxic component in senile plaques of Alzheimer's disease (AD) brains. Previously we have reported that Aß toxicity is mediated by the induction of sonic hedgehog (SHH) to trigger cell cycle re-entry (CCR) and apoptosis in post-mitotic neurons. Basella alba is a vegetable whose polysaccharides carry immunomodulatory and anti-cancer actions, but their protective effects against neurodegeneration have never been reported. Herein, we tested whether polysaccharides derived from Basella alba (PPV-6) may inhibit Aß toxicity and explored its underlying mechanisms. In differentiated rat cortical neurons, Aß25-35 reduced cell viability, damaged neuronal structure, and compromised mitochondrial bioenergetic functions, all of which were recovered by PPV-6. Immunocytochemistry and western blotting revealed that Aß25-35-mediated induction of cell cycle markers including cyclin D1, proliferating cell nuclear antigen (PCNA), and histone H3 phosphorylated at Ser-10 (p-Histone H3) in differentiated neurons was all suppressed by PPV-6, along with mitigation of caspase-3 cleavage. Further studies revealed that PPV-6 inhibited Aß25-35 induction of SHH; indeed, PPV-6 was capable of suppressing neuronal CCR and apoptosis triggered by the exogenous N-terminal fragment of sonic hedgehog (SHH-N). Our findings demonstrated that, in the fully differentiated neurons, PPV-6 exerts protective actions against Aß neurotoxicity via the downregulation of SHH to suppress neuronal CCR and apoptosis.
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Péptidos beta-Amiloides , Apoptosis , Ciclo Celular , Proteínas Hedgehog , Neuronas , Polisacáridos , Péptidos beta-Amiloides/metabolismo , Péptidos beta-Amiloides/toxicidad , Proteínas Hedgehog/metabolismo , Animales , Neuronas/efectos de los fármacos , Neuronas/metabolismo , Apoptosis/efectos de los fármacos , Ratas , Polisacáridos/farmacología , Polisacáridos/química , Ciclo Celular/efectos de los fármacos , Fragmentos de Péptidos , Supervivencia Celular/efectos de los fármacos , Fármacos Neuroprotectores/farmacologíaRESUMEN
This meta-analysis summarizes evidence from 44 neuroimaging experiments and characterizes the general linguistic network in early deaf individuals. Meta-analytic comparisons with hearing individuals found that a specific set of regions (in particular the left inferior frontal gyrus and posterior middle temporal gyrus) participates in supramodal language processing. In addition to previously described modality-specific differences, the present study showed that the left calcarine gyrus and the right caudate were additionally recruited in deaf compared with hearing individuals. In addition, this study showed that the bilateral posterior superior temporal gyrus is shaped by cross-modal plasticity, whereas the left frontotemporal areas are shaped by early language experience. Although an overall left-lateralized pattern for language processing was observed in the early deaf individuals, regional lateralization was altered in the inferior temporal gyrus and anterior temporal lobe. These findings indicate that the core language network functions in a modality-independent manner, and provide a foundation for determining the contributions of sensory and linguistic experiences in shaping the neural bases of language processing.
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The commercial applications of lead halide perovskites are hindered by their negative environmental impact and inherent instability. Consequently, developing environmentally friendly copper-based perovskite materials is crucial for future solid-state lighting and display applications. In this study, an ultrafast high-power ultrasonic synthesis strategy was utilized to achieve uniform nucleation and growth of Cs3Cu2X5 (X = Cl, Br, I) nanocrystals (NCs) that possess remarkable luminescence properties, hydroxyl protection, and ligand-free characteristics. These Cs3Cu2X5 NCs exhibited a tunable spectral range spanning from 446 to 525 nm, accompanied by photoluminescence quantum yields (PLQYs) varying from 0.2% to 79.2%. The spectral attributes of the NCs were effectively controlled by modulating the halide type and composition. It is worth noting that density functional theory (DFT) calculations offer valuable insights into the synthesis of NCs and the selection of suitable alcohol solvents. Moreover, we successfully fabricated an efficient and stable white light-emitting diode (WLED) with a high luminous efficiency of 23 lm W-1 and CIE color coordinates of (0.3266, 0.3487). Our work provides a new strategy to synthesize Cs3Cu2X5 NCs and holds promise for their potential application in display and lighting devices.
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The screening of based target compounds supported by LC/MS, MS/MS and Global Natural Products Social (GNPS) used to identify the compounds 1-10 of Butea monsperma. They were evaluated in human malignant embryonic rhabdomyoma cells (RD cells) infected with Human coronavirus OC43 (HCoV-OC43) and showed significant inhibitory activity. Target inhibition tests showed that compounds 6 and 8 inhibited the proteolytic enzyme 3CLpro, which is widely present in coronavirus and plays an important role in the replication process, with an effective IC50 value. The study confirmed that dioxymethylene of compound 8 may be a key active fragment in inhibiting coronavirus (EC50 7.2 µM, SI > 139.1). The results have led to identifying natural bioactive compounds for possible inhibiting HCoV-OC43 and developing drug for Traditional Chinese Medicine (TCM).
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Antivirales , Coronavirus Humano OC43 , Flavonoides , Humanos , Flavonoides/farmacología , Flavonoides/aislamiento & purificación , Flavonoides/química , Cromatografía Liquida , Estructura Molecular , Coronavirus Humano OC43/aislamiento & purificación , Coronavirus Humano OC43/efectos de los fármacos , Antivirales/farmacología , Antivirales/aislamiento & purificación , Espectrometría de Masas en Tándem , Línea Celular Tumoral , Proteasas 3C de Coronavirus/antagonistas & inhibidores , Productos Biológicos/farmacología , Productos Biológicos/aislamiento & purificación , Productos Biológicos/químicaRESUMEN
Objective: This study focuses on enhancing the precision of epidemic time series data prediction by integrating Gated Recurrent Unit (GRU) into a Graph Neural Network (GNN), forming the GRGNN. The accuracy of the GNN (Graph Neural Network) network with introduced GRU (Gated Recurrent Units) is validated by comparing it with seven commonly used prediction methods. Method: The GRGNN methodology involves multivariate time series prediction using a GNN (Graph Neural Network) network improved by the integration of GRU (Gated Recurrent Units). Additionally, Graphical Fourier Transform (GFT) and Discrete Fourier Transform (DFT) are introduced. GFT captures inter-sequence correlations in the spectral domain, while DFT transforms data from the time domain to the frequency domain, revealing temporal node correlations. Following GFT and DFT, outbreak data are predicted through one-dimensional convolution and gated linear regression in the frequency domain, graph convolution in the spectral domain, and GRU (Gated Recurrent Units) in the time domain. The inverse transformation of GFT and DFT is employed, and final predictions are obtained after passing through a fully connected layer. Evaluation is conducted on three datasets: the COVID-19 datasets of 38 African countries and 42 European countries from worldometers, and the chickenpox dataset of 20 Hungarian regions from Kaggle. Metrics include Average Root Mean Square Error (ARMSE) and Average Mean Absolute Error (AMAE). Result: For African COVID-19 dataset and Hungarian Chickenpox dataset, GRGNN consistently outperforms other methods in ARMSE and AMAE across various prediction step lengths. Optimal results are achieved even at extended prediction steps, highlighting the model's robustness. Conclusion: GRGNN proves effective in predicting epidemic time series data with high accuracy, demonstrating its potential in epidemic surveillance and early warning applications. However, further discussions and studies are warranted to refine its application and judgment methods, emphasizing the ongoing need for exploration and research in this domain.
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Redes Neurales de la Computación , Humanos , COVID-19/epidemiología , Enfermedades Transmisibles/epidemiología , Análisis de Fourier , Brotes de EnfermedadesRESUMEN
Background: The ageing population presents a substantial challenge to conventional care services for older adults in China. College students' voluntary service constitutes an integral component of youth volunteerism, and investigating their continuing willingness to engage in volunteer services to benefit older adults holds immense importance for fostering a stable and enduring framework for China's older adults' care team. Method: Drawing on the extended theory of reasoned action, this study establishes an analytical framework to examine the willingness of Chinese college students to engage in volunteer services for older adults. Using micro-survey data, we employ structural equation modelling and the bootstrap mediation effect test method to empirically investigate the influencing mechanism behind this willingness. Results: (1) Attitude has the strongest influence on the continuing willingness of Chinese college students to engage in volunteer services for older adults, and plays a mediating role between subjective norms and continuing willingness to engage in volunteer services, which reveals the special role of attitude in the continuing engagement of Chinese college students in volunteer services for older adults. (2) Personality trait has a substantial positive impact on Chinese college students' willingness to engage continuously in volunteer service for older adults, and subjective norms and attitudes have a chain mediating effect in this influence relationship. (3) The theoretical model constructed in this study is reasonable, reliable and robust. Conclusion: This study elucidates the potential relationship between attitude, subjective norms, personality traits and the willingness to engage in volunteer services, offering a novel perspective for understanding the continuing willingness of Chinese college students to engage in volunteer services for older adults. Furthermore, it highlights the value of incorporating the extended theory of reasoned action into the policy design of college students' engagement in such services.
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This study aimed to identify possible pathogenic genes in a 90-member family with a rare combination of multiple neurodegenerative disease phenotypes, which has not been depicted by the known neurodegenerative disease. We performed physical and neurological examinations with International Rating Scales to assess signs of ataxia, Parkinsonism, and cognitive function, as well as brain magnetic resonance imaging scans with seven sequences. We searched for co-segregations of abnormal repeat-expansion loci, pathogenic variants in known spinocerebellar ataxia-related genes, and novel rare mutations via whole-genome sequencing and linkage analysis. A rare co-segregating missense mutation in the CARS gene was validated by Sanger sequencing and the aminoacylation activity of mutant CARS was measured by spectrophotometric assay. This pedigree presented novel late-onset core characteristics including cerebellar ataxia, Parkinsonism, and pyramidal signs in all nine affected members. Brain magnetic resonance imaging showed cerebellar/pons atrophy, pontine-midline linear hyperintensity, decreased rCBF in the bilateral basal ganglia and cerebellar dentate nucleus, and hypo-intensities of the cerebellar dentate nuclei, basal ganglia, mesencephalic red nuclei, and substantia nigra, all of which suggested neurodegeneration. Whole-genome sequencing identified a novel pathogenic heterozygous mutation (E795V) in the CARS gene, meanwhile, exhibited none of the known repeat-expansions or point mutations in pathogenic genes. Remarkably, this CARS mutation causes a 20% decrease in aminoacylation activity to charge tRNACys with L-cysteine in protein synthesis compared with that of the wild type. All family members carrying a heterozygous mutation CARS (E795V) had the same clinical manifestations and neuropathological changes of Parkinsonism and spinocerebellar-ataxia. These findings identify novel pathogenesis of Parkinsonism-spinocerebellar ataxia and provide insights into its genetic architecture.
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Preeclampsia is a multisystem progressive condition and is one of the most serious complications of pregnancy. Owing to its unclear pathogenesis, there are no precise and effective therapeutic targets for preeclampsia, and the only available treatment strategy is to terminate the pregnancy and eliminate the clinical symptoms. In recent years, non-coding RNAs have become a hotspot in preeclampsia research and have shown promise as effective biomarkers for the early diagnosis of preeclampsia over conventional biochemical markers. PIWI-interacting RNAs, novel small non-coding RNA that interact with PIWI proteins, are involved in the pathogenesis of various diseases at the transcriptional or post-transcriptional level. However, the mechanisms underlying the role of PIWI-interacting RNAs in the pathogenesis of preeclampsia remain unclear. In this review, we discuss the findings of existing studies on PIWI-interacting RNA biogenesis, functions, and their possible roles in preeclampsia, providing novel insights into the potential application of PIWI-interacting RNAs in the early diagnosis and clinical treatment of preeclampsia.
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Preeclampsia , ARN Interferente Pequeño , Preeclampsia/metabolismo , Preeclampsia/genética , Preeclampsia/diagnóstico , Humanos , Femenino , Embarazo , ARN Interferente Pequeño/genética , ARN Interferente Pequeño/uso terapéutico , Biomarcadores/metabolismo , ARN de Interacción con PiwiRESUMEN
The prevalence of papillary thyroid cancer (PTC) has been rising in recent years. Despite its relatively low mortality, PTC frequently metastasizes to lymph nodes and often recurs, posing significant health and economic burdens. The role of iodine in the pathogenesis and advancement of thyroid cancer remains poorly understood. Circular RNAs (circRNAs) are recognized to function as competing endogenous RNAs (ceRNAs) that modulate gene expression and play a role in various cancer stages. Consequently, this research aimed to elucidate the mechanism by which circRNA influences the impact of iodine on PTC. Our research indicates that high iodine levels can exacerbate the malignancy of PTC via the circ_0004851/miR-296-3p/FGF11 axis. These insights into iodine's biological role in PTC and the association of circRNA with the disease could pave the way for novel biomarkers and potentially effective therapeutic strategies to mitigate PTC progression.
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Regulación Neoplásica de la Expresión Génica , Yodo , MicroARNs , ARN Circular , Cáncer Papilar Tiroideo , MicroARNs/genética , MicroARNs/metabolismo , ARN Circular/genética , ARN Circular/metabolismo , Humanos , Cáncer Papilar Tiroideo/genética , Cáncer Papilar Tiroideo/patología , Yodo/metabolismo , Línea Celular Tumoral , Neoplasias de la Tiroides/genética , Neoplasias de la Tiroides/patología , Secuencia de BasesRESUMEN
This paper proposes a dual-loop discrete-time adaptive control (DDAC) method for three-phase PWM rectifiers, which considers inductance-parameter-mismatched and DC load disturbances. A discrete-time model of the three-phase PWM rectifier is established using the forward Euler discretization method, and a dual-loop discrete-time feedback linearization control (DDFLC) is given. Based on the DDFLC, the DDAC is designed. Firstly, an adaptive inductance disturbance observer (AIDO) based on the gradient descent method is proposed in the current control loop. The AIDO is used to estimate lump disturbances caused by mismatched inductance parameters and then compensate for these disturbances in the current controller, ensuring its strong robustness to inductance parameters. Secondly, a load parameter adaptive law (LPAL) based on the discrete-time Lyapunov theory is proposed for the voltage control loop. The LPAL estimates the DC load parameter in real time and subsequently adjusts it in the voltage controller, achieving DC load adaptability. Finally, simulation and experimental results show that the DDAC exhibits better steady and dynamic performances, less current harmonic content than the DDFLC and the dual-loop discrete-time PI control (DDPIC), and a stronger robustness to inductance parameters and DC load disturbances.
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Colloidal quantum dots (CQDs) have been a hot research topic ever since they were successfully fabricated in 1993 via the hot injection method. The Nobel Prize in Chemistry 2023 was awarded to Moungi G. Bawendi, Louis E. Brus and Alexei I. Ekimov for the discovery and synthesis of quantum dots. The Internet of Things (IoT) has also attracted a lot of attention due to the technological advancements and digitalisation of the world. This review first aims to give the basics behind QD physics. After that, the history behind CQD synthesis and the different methods used to synthesize most widely researched CQD materials (CdSe, PbS and InP) are revisited. A brief introduction to what IoT is and how it works is also mentioned. Then, the most widely researched CQD devices that can be used for the main IoT components are reviewed, where the history, physics, the figures of merit (FoMs) and the state-of-the-art are discussed. Finally, the challenges and different methods for integrating CQDs into IoT devices are discussed, mentioning the future possibilities that await CQDs.
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The performance of blue quantum dot light-emitting diodes (QLEDs) is limited by unbalanced charge injection, resulting from insufficient holes caused by low mobility or significant energy barriers. Here, we introduce an angular-shaped heteroarene based on cyclopentane[b]thiopyran (C8-SS) to modify the hole transport layer poly-N-vinylcarbazole (PVK), in blue QLEDs. C8-SS exhibits high hole mobility and conductivity due to the π···π and S···π interactions. Introducing C8-SS to PVK significantly enhanced hole mobility, increasing it by 2 orders of magnitude from 2.44 × 10-6 to 1.73 × 10-4 cm2 V-1 s-1. Benefiting from high mobility and conductivity, PVK:C8-SS-based QLEDs exhibit a low turn-on voltage (Von) of 3.2 V. More importantly, the optimized QLEDs achieve a high peak power efficiency (PE) of 7.13 lm/W, which is 2.65 times that of the control QLEDs. The as-proposed interface engineering provides a novel and effective strategy for achieving high-performance blue QLEDs in low-energy consumption lighting applications.
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The complex pathogenesis of preeclampsia (PE), a significant contributor to maternal and neonatal mortality globally, is poorly understood despite substantial research. This review explores the involvement of exosomal microRNAs (exomiRs) in PE, focusing on their impact on the protein kinase B (AKT)/hypoxia-inducible factor 1-α (HIF1α)/vascular endothelial growth factor (VEGF) signaling pathway as well as endothelial cell proliferation and migration. Specifically, this article amalgamates existing evidence to reveal the pivotal role of exomiRs in regulating mesenchymal stem cell and trophoblast function, placental angiogenesis, the renin-angiotensin system, and nitric oxide production, which may contribute to PE etiology. This review emphasizes the limited knowledge regarding the role of exomiRs in PE while underscoring the potential of exomiRs as non-invasive biomarkers for PE diagnosis, prediction, and treatment. Further, it provides valuable insights into the mechanisms of PE, highlighting exomiRs as key players with clinical implications, warranting further exploration to enhance the current understanding and the development of novel therapeutic interventions.
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MicroARNs , Preeclampsia , Recién Nacido , Humanos , Embarazo , Femenino , MicroARNs/genética , MicroARNs/metabolismo , Placenta/metabolismo , Preeclampsia/diagnóstico , Preeclampsia/genética , Preeclampsia/metabolismo , Factor A de Crecimiento Endotelial Vascular/metabolismo , Biomarcadores/metabolismoRESUMEN
BACKGROUND: Structural and functional brain imaging studies have reported abnormalities of gray matter morphology and functional activities in patients with rheumatoid arthritis (RA). However, it is largely unknown whether patients with RA show alterations of white matter microstructural organization. OBJECTIVES: To automatically identify alteration of white matter microstructure in patients with RA and further examine how this alteration associates with clinical characteristics. METHODS: This single-institutional prospective study included 66 participants (33 patients with RA [52 ± 9 years, 29 women] and 33 sex/age-matched healthy controls [53 ± 12 years, 27 women]), who underwent diffusion MRI scan from January 2021 to December 2021. The white matter microstructure was assessed using fractional anisotropy, mean diffusivity, axial diffusivity, and radial diffusivity. Voxelwise analyses were conducted on white matter skeleton using an automated, observer-independent tract-based spatial statistics analysis. The relationship between white matter microstructural alterations and clinical and neuropsychological variables was evaluated using correlation analysis. RESULTS: Compared with healthy controls, patients with RA exhibited lower fractional anisotropy in several major white matter tracts (threshold-free cluster enhancement at P < 0.05 for multiple comparison correction, permutation test), involving the forceps minor, bilateral inferior fronto-occipital fasciculus, bilateral anterior thalamic radiation, and bilateral uncinate fasciculus. Lower fractional anisotropy values in the patients with RA were significantly associated with pain-related assessments, including tender joint count (r = -0.43, P = 0.015), Clinical Disease Activity Index score (r = -0.36, P = 0.049), pain severity rated through visual analogue scale (r = -0.45, P = 0.012), and Simplified Disease Activity Index score (r = -0.36, P = 0.045). No significant group difference was found in mean diffusivity, axial diffusivity, and radial diffusivity. CONCLUSIONS: We report the first anatomical evidence for aberrant microstructure organization of several major white matter tracts and its associations with pain processing in patients with rheumatoid arthritis.
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Artritis Reumatoide , Sustancia Blanca , Humanos , Femenino , Adulto , Persona de Mediana Edad , Anciano , Sustancia Blanca/diagnóstico por imagen , Estudios Prospectivos , Imagen de Difusión Tensora/métodos , Artritis Reumatoide/diagnóstico por imagen , Dolor , Anisotropía , Encéfalo/diagnóstico por imagenRESUMEN
The novel variant IBDV (nVarIBDV, genotype A2dB1), characterized by bursal atrophy of fabricius and decreased lymphocytes, has been emerging on a large scale in Asia (including China) since late 2018. nVarIBDV is a new threat to the poultry industry, yet the currently licensed commercial vaccines, including the live viral vector vaccine, IBDV immune complex vaccine or VP2 subunit vaccine, are ineffective against nVarIBDV infection. In this study, specific-pathogen-free (SPF) chickens and broilers divided into 3 groups were vaccinated with the live viral vector vaccine, the VP2 subunit vaccine or the IBDV immune complex vaccine at 1 day-old, respectively. The SPF chickens received a secondary vaccination with the live B87 strain vaccine at 11-day-old. The bursa/body weight ratio, histopathology lesion of the bursa, and the differentiation between infected and vaccinated animals (DIVA) by qRT-PCR confirmed that the live viral vector vaccine or immune complex vaccine plus live B87 strain booster could provide at least 80% protection against the FJ2019-01 strain of nVarIBDV in SPF chickens. The broilers also received a secondary vaccination using a live W2512 G-61 strain vaccine at 14-day-old, and analyses showed that the VP2 subunit vaccine or immune complex vaccine plus the live W2512 G-61 strain booster also provided more than 80% protection against the FJ2019-01 strain of nVarIBDV. Unfortunately, the live viral vector vaccine plus live W2512 G-61 strain booster provided poor to moderate protection against FJ2019-01 in broilers. These findings suggest that combining commercial vaccines with rational booster immunization can effectively protect chickens against an nVarIBDV challenge.
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Infecciones por Birnaviridae , Virus de la Enfermedad Infecciosa de la Bolsa , Enfermedades de las Aves de Corral , Vacunas Virales , Animales , Pollos , Inmunización Secundaria/veterinaria , Complejo Antígeno-Anticuerpo , Infecciones por Birnaviridae/prevención & control , Infecciones por Birnaviridae/veterinaria , Vacunas Atenuadas , Vacunas de Subunidad , Anticuerpos Antivirales , Bolsa de Fabricio/patologíaRESUMEN
Plastic crystals as barocaloric materials exhibit the large entropy change rivalling freon, however, the limited pressure-sensitivity and large hysteresis of phase transition hinder the colossal barocaloric effect accomplished reversibly at low pressure. Here we report reversible colossal barocaloric effect at low pressure in two-dimensional van-der-Waals alkylammonium halides. Via introducing long carbon chains in ammonium halide plastic crystals, two-dimensional structure forms in (CH3-(CH2)n-1)2NH2X (X: halogen element) with weak interlayer van-der-Waals force, which dictates interlayer expansion as large as 13% and consequently volume change as much as 12% during phase transition. Such anisotropic expansion provides sufficient space for carbon chains to undergo dramatic conformation disordering, which induces colossal entropy change with large pressure-sensitivity and small hysteresis. The record reversible colossal barocaloric effect with entropy change ΔSr ~ 400 J kg-1 K-1 at 0.08 GPa and adiabatic temperature change ΔTr ~ 11 K at 0.1 GPa highlights the design of novel barocaloric materials by engineering the dimensionality of plastic crystals.
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Low-temperature co-fired ceramic (LTCC) substrate materials are widely applied in electronic components due to their excellent microwave dielectric properties. However, the absence of LTCC materials with a lower dielectric constant and higher mechanical strength restricts the creation of integrated and minified electronic devices. In this work, sol-gel-derived CaO-B2O3-SiO2 (CBS) glass/Al2O3 composites with high flexural strength and low dielectric constant were successfully prepared using the LTCC technique. Among the composites sintered at different temperatures, the composites sintered at 870 °C for 2 hours possess a dielectric constant of 6.3 (10 GHz), a dielectric loss of 0.2%, a flexural strength of 245 MPa, and a CTE of 5.3 × 10-6 K-1, demonstrating its great potential for applications in the electronic package field. By analyzing the CBS glass' physical characteristics, it was found that the sol-gel-derived glass has an extremely low dielectric constant of 3.6 and does not crystallize or react with Al2O3 at the sintering temperature, which is conducive to improving the flexural strength and reducing the dielectric constant of CBS glass/Al2O3 composites.
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Chitin microspheres (CMs) have attracted increasing attention due to their biocompatibility, uniform size and shape, large surface area, and porous structure. Considerable research efforts have been focused on developing CMs and promoting their applications in various areas. In this context, this review aims to describe the most recent progress in the fabrication and application of CMs. Different routes that can be used to prepare CMs, such as the drip method and the emulsion method, are emphatically introduced. Moreover, the applications of CMs as drug delivery systems, wound dressings, three-dimensional (3D) scaffolds, water purification, and functional supporting materials in the fields of biomedicine, tissue engineering, environmental protection, and energy storage are also highlighted. We hope this review can provide a comprehensive and useful database for further innovation of CMs.