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1.
Vet Res ; 55(1): 61, 2024 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-38750508

RESUMEN

Porcine reproductive and respiratory syndrome (PRRS), a highly contagious disease caused by Porcine reproductive and respiratory syndrome virus (PRRSV), results in huge economic losses to the world pig industry. MiRNAs have been reported to be involved in regulation of viral infection. In our study, miR-320 was one of 21 common differentially expressed miRNAs of Meishan, Pietrain, and Landrace pig breeds at 9-h post-infection (hpi). Bioinformatics and experiments found that PRRSV replication was inhibited by miR-320 through directly targeting PRRSV ORF6. In addition, the expression of CCAAT enhancer binding protein beta (CEBPB) was also inhibited by miR-320 by targeting the 3' UTR of CEBPB, which significantly promotes PRRSV replication. Intramuscular injection of pEGFP-N1-miR-320 verified that miR-320 significantly inhibited the replication of PRRSV and alleviated the symptoms caused by PRRSV in piglets. Taken together, miR-320 have significant roles in the infection and may be promising therapeutic target for PRRS.


Asunto(s)
MicroARNs , Síndrome Respiratorio y de la Reproducción Porcina , Virus del Síndrome Respiratorio y Reproductivo Porcino , Replicación Viral , Animales , MicroARNs/genética , MicroARNs/metabolismo , Porcinos , Virus del Síndrome Respiratorio y Reproductivo Porcino/fisiología , Síndrome Respiratorio y de la Reproducción Porcina/virología , Proteína beta Potenciadora de Unión a CCAAT/metabolismo , Proteína beta Potenciadora de Unión a CCAAT/genética
2.
J Org Chem ; 88(22): 15913-15924, 2023 Nov 17.
Artículo en Inglés | MEDLINE | ID: mdl-37924300

RESUMEN

A novel [4 + 1] and [5 + 1] dearomative spiroannulation has been developed by the use of commercial naphthols and phenols with dielectrophiles. Various spirocycles, including spiro[4.5] and spiro[5.5] have been constructed successfully by employing four-atom or five-atom dielectrophilic synthons. This transformation was realized through a sequence of site-selective C-alkylation/dearomative spiroannulation. Moreover, the potential application of this method was exemplified by several further transformation.

3.
Front Public Health ; 11: 1117923, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37275481

RESUMEN

Background: In 2017, the Chinese government launched a pilot project in palliative care, in which Shanghai was a pioneer. Nurses play a key role in palliative care services as they are the main providers improving the quality of services for patients and their families. However, little is known about practices and influencing factors in the field of palliative care from a nursing perspective in China. This is an original empirical study that has meticulously analyzed the interrelationship and intensity between practices and other factors among nurses in the initial stage of palliative care in primary healthcare institutions in Shanghai, China. Methods: A descriptive-correlational study design was used to sample 2,829 eligible palliative care nurses by purposive sampling survey in 225 healthcare institutions in Shanghai, China. Descriptive analyses were performed using IBM SPSS 24.0 software. Structural equation modeling was applied to analyze the data by AMOS 20.0. Data were collected using the well-designed Knowledge, Attitudes, and Practices of Hospice Care (KAPHC) scale. Results: The final model showed a good model fit. Self-efficacy directly influenced practices (ß = 0.506, P < 0.01) and indirectly influenced practices (ß = 0.028, P < 0.01) through intention. Subjective norm directly influenced practices (ß = 0.082, P < 0.01) and indirectly influenced practices (ß = 0.030, P < 0.01) through intention. Intention (ß = 0.152, P < 0.01) and knowledge (ß = 0.068, P < 0.01) directly influenced practices. Perceived susceptibility (ß = -0.027, P < 0.01), perceived benefits (ß = -0.017, P < 0.01), and perceived barriers (ß = -0.014, P < 0.01) indirectly influenced practices through intention. Conclusion: This study provided evidence of the associations of knowledge, perceived susceptibility, benefits, barriers, subjective norm, self-efficacy, intention, and practices among nurses concerning palliative care and interventions improving their actual work practices. Our findings revealed that self-efficacy, intention, and subjective norms greatly influenced practices. It is imperative to take interventions that focus precisely on self-efficacy, intention, and subjective norms to improve nurses' practices.


Asunto(s)
Enfermeras y Enfermeros , Cuidados Paliativos , Humanos , Proyectos Piloto , China , Actitud
4.
Bioresour Technol ; 380: 129076, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-37088432

RESUMEN

This study proposes a novel method to enhance methane production from anaerobic digestion using an amino acid-derived ionic liquid, glycine hydrochloride, ([Gly][Cl]), as an exogenous additive. After 40 days of digestion with 5% [Gly][Cl], the cumulative methane production was 115.56 mL/g VS, which was 73% higher than that of the control group (without additive). Specifically, the peak activities of cellulase, xylanase, and lignin peroxidase were significantly higher than those of the control group. The addition of [Gly][Cl] increased bacterial diversity and reduced archaeal diversity. Synergistota represented by Syner-01, Fibrobacterota represented by BBMC-4, Bacteroides, and unclassified_f__Lachnospiraceae significantly increased in relative abundance. It suggested that [Gly][Cl] stimulated the activities of protein-hydrolyzing and acid-producing bacteria. [Gly][Cl] also increased the abundance of methanogens and archaea, converting more lignocellulose to methane. Methanobacterium, that metabolizes H2 and CO2 to CH4, was more abundant. Therefore, [Gly][Cl] can improve methane yield as an anaerobic digestion additive.


Asunto(s)
Líquidos Iónicos , Oryza , Anaerobiosis , Oryza/metabolismo , Líquidos Iónicos/farmacología , Aminoácidos/metabolismo , Bacterias/metabolismo , Archaea/metabolismo , Clostridiales/metabolismo , Metano , Reactores Biológicos/microbiología
5.
Angew Chem Int Ed Engl ; 61(3): e202113820, 2022 Jan 17.
Artículo en Inglés | MEDLINE | ID: mdl-34783149

RESUMEN

Polar disconnection of the C(sp3 )-N bond of N,N-dialkyl-substituted tertiary amines via ammonium species conventionally favored the loss of the smaller alkyl group by an SN 2 displacement, while selective C(sp3 )-N bond cleavage by cutting off the larger alkyl group is still underdeveloped. Herein, we present a novel Pd0 -catalyzed [2+2+1] annulation, proceeding through an alkyne-directed palladacycle formation and consecutive diamination with a tertiary hydroxylamine by cleaving its N-O bond and one C(sp3 )-N bond, for the rapid assembly of tricyclic indoles in a single-step transformation. Noteworthy, experimental results indicated that large tert-butyl and benzyl groups were selectively cleaved via an SN 1 pathway, in the presence of a smaller alkyl group (Me, Et, i Pr). Under the guidance of this new finding, tricyclic indoles bearing a removable alkyl group could be exclusively obtained by using a (α-methyl)benzyl/benzyl or tert-butyl/2-(methoxycarbonyl)ethyl mixed amino source.

6.
Environ Technol ; 43(12): 1892-1902, 2022 May.
Artículo en Inglés | MEDLINE | ID: mdl-33251969

RESUMEN

It is effective to adsorb phosphate and ammonium from water by sludge-based biochar, while the desorption performance has not been studied systematically. Biochar in this study was prepared through the co-pyrolysis of sludge and walnut shells to remove NH4+ and PO43- from water. The desorption characteristics of NH4+ and PO43- from the post-adsorption sludge-based biochar were investigated. The effects of the adsorption condition (concentration of adsorption solution) and desorption conditions (pH value of desorption solution and desorption temperature and time) on desorption performance were examined. Several techniques were performed to characterise the properties of the post-adsorption sludge-based biochar. The adsorption amount of the pure sewage sludge biochar (SBC) for PO43- and the biochar derived from the co-pyrolysis of sewage sludge and walnut shell with the mixing ratio of 3:1 (MBC3-1) for NH4+ were 14.19/ 23.75 mg/g and 9.28/ 16.23 mg/g, respectively, when the concentrations of the adsorbates were 100 and 500 mg/L. The desorption experiments showed that the acidic condition (pH = 2) was beneficial for PO43- and NH4+ desorption. The highest desorption ratio reached 7.58% for PO43- and 2.18% for NH4+. The desorption of PO43- was endothermic, whereas that of NH4+ was exothermic. The desorption amounts of PO43- and NH4+ decreased and increased, respectively, with the increase in desorption time. This study of the desorption characteristics of PO43- and NH4+ in sludge-based biochar provides a theoretical basis for the subsequent utilisation of sludge-based biochar.


Asunto(s)
Compuestos de Amonio , Aguas del Alcantarillado , Adsorción , Carbón Orgánico , Fosfatos , Agua
7.
Chemosphere ; 269: 129374, 2021 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-33385666

RESUMEN

Phosphate removal in water using biochar is widely investigated. Density functional theory was used to study the adsorption of phosphate (H2PO4-) on biochar in water after metal modification. Two types of metals, Mg and Ca, were used to modify the biochar structure, and the edge and metal adsorptions of H2PO4- were investigated on the modified biochar structure. Results were analyzed from the aspects of structural stability, adsorption energy, change in dipole moment, density of electronic states, and atoms in molecules analysis. The overall effect of metal-modified biochar materials on phosphate adsorption was stronger than that of unmodified biochar materials in terms of molecular level. The stability of the metal-modified structure by adding metal was low, and adsorption was prone to occur in this situation. The Ca-modified biochar showed better phosphate adsorption than the Mg-modified structure. Metal adsorption performed better than edge adsorption, proving that the modified metal in the biochar structure played a leading role in H2PO4- adsorption. Metal adsorption was mainly caused by electrostatic attraction, and edge adsorption was mainly caused by covalent bonding.


Asunto(s)
Fosfatos , Contaminantes Químicos del Agua , Adsorción , Carbón Orgánico , Agua , Contaminantes Químicos del Agua/análisis
8.
J Environ Manage ; 249: 109410, 2019 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-31446122

RESUMEN

Pyrolysis of sewage sludge to obtain biochar is an environmentally friendly method of sewage sludge utilization. In this study, sewage sludge and walnut shell were co-pyrolyzed to produce biochar, which was utilized in the adsorption of ammonium and phosphate from water. Brunauer-Emmett-Teller analysis, X-ray diffraction spectroscopy, scanning electron microscopy, and Fourier transform infrared techniques were applied to analyze the physical and chemical properties of the biochar. The sewage sludge-based biochar consisted of rich metal oxides and functional groups, and the addition of walnut shell was beneficial for the development of porous structure. When the mixing ratio of sewage sludge and walnut shell was 3:1, the derived biochar (MBC3-1) showed a high adsorption capacity for NH4+ in neutral or weak alkaline water. Pure sewage sludge biochar (SBC) was the best option for the adsorption of PO43- in a wide pH range of water. The adsorption of NH4+ and v on MBC3-1 and SBC were controlled by intraparticle diffusion and pseudo-second-order kinetic models, respectively. Isothermal studies indicated that multiple adsorption processes occurred in the adsorption of NH4+ and PO43-, and the maximum adsorption capacity of NH4+ and PO43- reached 22.85 mg/g and 303.49 mg/g on MBC3-1 and SBC, respectively. Thermodynamic analysis confirmed the exothermic and endothermic nature for NH4+ and PO43- adsorption on biochar, respectively.


Asunto(s)
Compuestos de Amonio , Juglans , Adsorción , Carbón Orgánico , Fosfatos , Pirólisis , Aguas del Alcantarillado , Agua
9.
J Chem Phys ; 150(23): 234307, 2019 Jun 21.
Artículo en Inglés | MEDLINE | ID: mdl-31228902

RESUMEN

Glassing matrix deuteration could be a beneficial sample preparation method for 13C dynamic nuclear polarization (DNP) when large electron paramagnetic resonance (EPR) width free radicals are used. However, it could yield the opposite DNP effect when samples are doped with small EPR width free radicals. Herein, we have investigated the influence of solvent deuteration on the 13C nuclear and electron relaxation that go along with the effects on 13C DNP intensities at 3.35 T and 1.2 K. For 13C DNP samples doped with trityl OX063, the 13C DNP signals decreased significantly when the protons are replaced by deuterons in glycerol:water or DMSO:water solvents. Meanwhile, the corresponding solid-state 13C T1 relaxation times of trityl OX063-doped samples generally increased upon solvent deuteration. On the other hand, 13C DNP signals improved by a factor of ∼1.5 to 2 upon solvent deuteration of samples doped with 4-oxo-TEMPO. Despite this 13C DNP increase, there were no significant differences recorded in 13C T1 values of TEMPO-doped samples with nondeuterated or fully deuterated glassing matrices. While solvent deuteration appears to have a negligible effect on the electron T1 relaxation of both free radicals, the electron T2 relaxation times of these two free radicals generally increased upon solvent deuteration. These overall results suggest that while the solid-phase 13C DNP signals are dependent upon the changes in total nuclear Zeeman heat capacity, the 13C relaxation effects are related to 2H/1H nuclear spin diffusion-assisted 13C polarization leakage in addition to the dominant paramagnetic relaxation contribution of free radical centers.

10.
Vis Comput Ind Biomed Art ; 2(1): 5, 2019 Jun 21.
Artículo en Inglés | MEDLINE | ID: mdl-32240392

RESUMEN

An unmanned aerial vehicle (UAV) is a small, fast aircraft with many useful features. It is widely used in military reconnaissance, aerial photography, searches, and other fields; it also has very good practical-application and development prospects. Since the UAV's flight orientation is easily changeable, its orientation and flight path are difficult to control, leading to its high damage rate. Therefore, UAV flight-control technology has become the focus of attention. This study focuses on simulating a UAV's flight and orientation control, and detecting collisions between a UAV and objects in a complex virtual environment. The proportional-integral-derivative control algorithm is used to control the orientation and position of the UAV in a virtual environment. A version of the bounding-box method that combines a grid with a k-dimensional tree is adopted in this paper, to improve the system performance and accelerate the collision-detection process. This provides a practical method for future studies on UAV flight position and orientation control, collision detection, etc.

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