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1.
Fish Shellfish Immunol ; 149: 109574, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38692379

RESUMO

B-cell lymphoma/leukemia-2 (BCL2), an anti-apoptotic factor in the mitochondrial regulatory pathway of apoptosis, is critically important in immune defenses. In this study, a novel BCL2 gene was characterized from Pteria penguin (P. penguin). The PpBCL2 was 1482 bp long, containing an open reading frame (ORF) of 588 bp encoding 195 amino acids. Four highly conserved BCL-2 homology (BH) domains were found in PpBCL2. Amino acid alignment and phylogenetic tree showed that PpBCL2 had the highest similarity with BCL2 of Crassostrea gigas at 65.24 %. Tissue expression analysis showed that PpBCL2 had high constitutive expression in gill, digestive diverticulum and mantle, and was significantly increased 72 h of Vibrio parahaemolyticus (V. parahaemolyticus) challenge in these immune tissues. Furthermore, PpBCL2 silencing significantly inhibited antimicrobial activity of hemolymph supernatant by 1.4-fold, and significantly reduced the survival rate by 51.7 % at 72 h post infection in P. penguin. These data indicated that PpBCL2 played an important role in immune response of P. penguin against V. parahaemolyticus infection.


Assuntos
Sequência de Aminoácidos , Imunidade Inata , Filogenia , Proteínas Proto-Oncogênicas c-bcl-2 , Alinhamento de Sequência , Spheniscidae , Vibrio parahaemolyticus , Animais , Vibrio parahaemolyticus/fisiologia , Proteínas Proto-Oncogênicas c-bcl-2/genética , Proteínas Proto-Oncogênicas c-bcl-2/imunologia , Spheniscidae/imunologia , Spheniscidae/genética , Alinhamento de Sequência/veterinária , Imunidade Inata/genética , Regulação da Expressão Gênica/imunologia , Perfilação da Expressão Gênica/veterinária , Vibrioses/imunologia , Vibrioses/veterinária , Sequência de Bases
2.
Angew Chem Int Ed Engl ; 63(17): e202401969, 2024 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-38372671

RESUMO

Photocatalytic hydrogen production based on noble metal-free systems is a promising technology for the conversion of solar energy into green hydrogen, it is pivotal and challenging to tailor-make photocatalysts for achieving high photocatalytic efficiency. Herein, we reported a hollow double-shell dyad through uniformly coating covalent organic frameworks (COFs) on the surface of hollow Co9S8. The double shell architecture enhances the scattering and refraction efficiency of incident light, shortens the transmission distance of the photogenerated charge carriers, and exposes more active sites for photocatalytic conversion. The hydrogen evolution rate is as high as 23.15 mmol g-1 h-1, which is significantly enhanced when compared with that of their physical mixture (0.30 mmol g-1 h-1) and Pt-based counterpart (11.84 mmol g-1 h-1). This work provides a rational approach to the construction of noble-metal-free photocatalytic systems based on COFs to enhance hydrogen evolution performance.

3.
J Nurs Adm ; 53(5): 271-276, 2023 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-37098867

RESUMO

OBJECTIVE: This study aimed to describe the current situation and explore overwork predictors among ICU nurses in China. BACKGROUND: Overwork is a comprehensive condition of labor where employees work for extended periods with high intensity and high pressure, which can negatively affect their health. Limited literature exists regarding the prevalence, characteristics, professional identity, and environment of overwork among ICU nurses. METHODS: A cross-sectional design study was conducted. The Professional Identification Scale for Nurses, the Practice Environment Scale of the Nursing Work Index, and the Overwork Related Fatigue Scale (ORFS) were used. To explore relationships between variables, univariate analysis or bivariate correlations were used. Multiple regression was used to identify predictors of overwork. RESULTS: Almost 85% of nurses were categorized as overworked, of which, 30% were moderately to severely overworked. Gender, form of employment, stress related to ICU nursing technology and equipment updates, nurses' professional identity, and nurse working environment accounted for 36.6% in the ORFS. CONCLUSIONS: Overwork is common among ICU nurses. Nurse managers need to develop and implement strategies to better support nurses to prevent overwork.


Assuntos
Enfermeiros Administradores , Enfermeiras e Enfermeiros , Recursos Humanos de Enfermagem Hospitalar , Humanos , Estudos Transversais , Fadiga , Fatores de Risco , Unidades de Terapia Intensiva , Inquéritos e Questionários , Satisfação no Emprego
4.
Phys Chem Chem Phys ; 23(45): 25727-25735, 2021 Nov 24.
Artigo em Inglês | MEDLINE | ID: mdl-34755715

RESUMO

The effect of charged defects on the stability of implanted He and Y atoms has been fully investigated to gain insight into the occupation mechanism of defects in cubic ZrO2 using first-principles calculations. For the intrinsic point defects in ZrO2, the configurations of VO2+, IO2-, VZr4-, and IZr4+ are dominant, which have the lowest formation energy over the widest Fermi level range, respectively. He atoms at neutral Zr vacancies have the lowest incorporation energy (0.438 eV), illustrating that the VZr0 is probably the most stable trapping site for He atoms. For the Y atoms implanted in ZrO2, the most stable configuration of YZr1- is obtained over the widest Fermi level range. In the Y-doped ZrO2, the incorporation energy of He at the site of Oct2 interstitial is the lowest (1.058 eV). For He atoms trapped at vacancies, He-VZr0 has the lowest incorporation energy of 0.631 eV. These results indicate that He atoms preferentially occupy the sites of VZr0. The state of electric charge plays a significant role in the formation of defects in the ionic compound. The present simulation results provide a theoretical foundation for the effect of charged defects on the stability of He atoms, which contributes to the understanding of the microscopic solution behaviour of He atoms in perfect ZrO2 and Y-doped ZrO2.

5.
World J Microbiol Biotechnol ; 35(10): 150, 2019 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-31549229

RESUMO

This study aimed to characterize a powerful antifungal component from bacteria. Bacillus subtilis strain XB-1, which showed maximal inhibition of Monilinia fructicola, was isolated and identified, and an antifungal protein was obtained from it. Ammonium sulfate precipitation, ion exchange chromatography, and sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) were used to purify and identify the proteins secreted by B. subtilis XB-1. Analyses revealed that purified fraction V had the strongest antifungal effect, with the largest pathogen inhibition zone diameter of 4.15 cm after 4 days (P < 0.05). This fraction showed a single band with a molecular weight of approximately 43 kDa in SDS-PAGE. Results from SDS-PAGE and liquid chromatography electrospray ionization tandem mass spectrometry analyses demonstrated that fraction V was likely a member of the chitosanase family. These results suggest that B. subtilis XB-1 and its antifungal protein may be useful in potential biocontrol applications.


Assuntos
Antifúngicos/isolamento & purificação , Antifúngicos/farmacologia , Bacillus subtilis/química , Proteínas de Bactérias/isolamento & purificação , Proteínas de Bactérias/farmacologia , Glicosídeo Hidrolases/isolamento & purificação , Glicosídeo Hidrolases/farmacologia , Antifúngicos/química , Ascomicetos/efeitos dos fármacos , Ascomicetos/crescimento & desenvolvimento , Bacillus subtilis/metabolismo , Proteínas de Bactérias/química , Cromatografia por Troca Iônica , Eletroforese em Gel de Poliacrilamida , Glicosídeo Hidrolases/química , Peso Molecular
6.
Sensors (Basel) ; 18(4)2018 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-29642648

RESUMO

To address the problem of estimating camera trajectory and to build a structural three-dimensional (3D) map based on inertial measurements and visual observations, this paper proposes point-line visual-inertial odometry (PL-VIO), a tightly-coupled monocular visual-inertial odometry system exploiting both point and line features. Compared with point features, lines provide significantly more geometrical structure information on the environment. To obtain both computation simplicity and representational compactness of a 3D spatial line, Plücker coordinates and orthonormal representation for the line are employed. To tightly and efficiently fuse the information from inertial measurement units (IMUs) and visual sensors, we optimize the states by minimizing a cost function which combines the pre-integrated IMU error term together with the point and line re-projection error terms in a sliding window optimization framework. The experiments evaluated on public datasets demonstrate that the PL-VIO method that combines point and line features outperforms several state-of-the-art VIO systems which use point features only.

7.
Artigo em Inglês | MEDLINE | ID: mdl-38917283

RESUMO

Object pose estimation constitutes a critical area within the domain of 3D vision. While contemporary state-of-the-art methods that leverage real-world pose annotations have demonstrated commendable performance, the procurement of such real training data incurs substantial costs. This paper focuses on a specific setting wherein only 3D CAD models are utilized as a priori knowledge, devoid of any background or clutter information. We introduce a novel method, CPPF++, designed for sim-to-real category-level pose estimation. This method builds upon the foundational point-pair voting scheme of CPPF, reformulating it through a probabilistic view. To address the challenge posed by vote collision, we propose a novel approach that involves modeling the voting uncertainty by estimating the probabilistic distribution of each point pair within the canonical space. Furthermore, we augment the contextual information provided by each voting unit through the introduction of N-point tuples. To enhance the robustness and accuracy of the model, we incorporate several innovative modules, including noisy pair filtering, online alignment optimization, and a tuple feature ensemble. Alongside these methodological advancements, we introduce a new category-level pose estimation dataset, named DiversePose 300. Empirical evidence demonstrates that our method significantly surpasses previous sim-to-real approaches and achieves comparable or superior performance on novel datasets. Our code is available on https://github.com/qq456cvb/CPPF2.

8.
Chem Commun (Camb) ; 60(47): 6039-6042, 2024 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-38775147

RESUMO

It is a challenge to design a photocathode with well-defined active sites for efficient photoelectrocatalytic CO2 reduction. Herein, single-atom Ni sites are integrated into Si nanowires to develop a novel photocathode, denoted as Ni-NC/Si. The photocathode demonstrates a stable faradaic efficiency for CO production, approaching nearly 100% at -0.6 V vs. RHE. The introduction of single-atom Ni sites provides sufficient active sites for CO2 reduction, thereby improving the selectivity towards CO formation.

9.
Rev Sci Instrum ; 95(1)2024 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-38197769

RESUMO

The geological conditions of hot dry rock (HDR) reservoirs are complex. The geothermal mining of HDR faces major challenges in the drilling and construction of wells, fracturing to create storage, and flowing to extract heat. Vibration impacts help improve the rock-breaking efficiency, where the axial-torsional coupled vibration impact technology can increase the bit penetration depth and reduce the stick-slip effect. To study the feasibility and efficiency of the axial-torsional-coupled vibration impact-assisted Polycrystalline Diamond Compact (PDC) bit to break high-temperature and high-pressure rocks, a new experimental setup was designed. The system includes a drilling fluid circulation system, an axial-torsional coupled impact drilling system, a formation simulation system, and a data acquisition and control system. This setup can produce a rock-breaking torque of 2000 N·m, a drilling speed of 200 rpm, a weight on bit of 100 kN, an axial vibration frequency of 100 Hz, and a torsional vibration frequency of 50 Hz. It can simulate the formation pressure of 70 MPa and the rock temperature of 400 °C. A series of rock-breaking drilling experiments were successfully conducted using this setup. The results show that the axial-torsional coupled vibration-impact assisted PDC bit has a good performance in breaking high-temperature and hard rocks, which can accelerate the application of this new technology in deep formation drilling.

10.
Materials (Basel) ; 16(15)2023 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-37570121

RESUMO

Introducing a coating shell between the filler and matrix is an effective way to reduce the dielectric loss of the particle/matrix dielectric composites. It found that besides the improvement in interface compatibility, there may be some other effects of the coating shell, such as the elimination of the dielectric mismatch. However, the specific mechanism is still unclear due to the absence of an effective model for the quantitative analysis of the relationship between core-shell structure and dielectric loss, hindering the progress of the dielectric composite design. Here, a phase-field model for simulating high-frequency, alternating-field polarization is employed to study the relationship between high-frequency polarization loss and the coating shell in the silicon dioxide coating boron nitride polytetrafluoroethylene-based (BN@SiO2/PTFE) composite. The results show that the dielectric mismatch makes the high-frequency polarization loss spatially localized and periodically time-variant. The reduction of polarization loss depends on the polarization loss of SiO2. To reduce the high-frequency dielectric loss of the composite, the coating shell should not only eliminate the dielectric mismatch, but its dielectric loss must also be lower than that of the core filler. Furthermore, the model provided in this work has the potential to extend the quantitative calculation of non-intrinsic polarization loss and conduction loss.

11.
Dalton Trans ; 51(12): 4786-4789, 2022 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-35253824

RESUMO

The heteroscorpionate zinc hydride complex LZnH 2, (L = (MePz)2CP(Ph)2NPh, MePz = 3,5-dimethylpyrazolyl), its formate complex 3, and magnesium hydride complex LMgH 5 with the same ligand were synthesized and detected for the catalytic hydroboration reaction of CO2. With BH3·SMe2 as the reductant, zinc-based hydride complex 2 and formate complex 3 show a similar capability of hydroboration of CO2, featuring excellent reactivity and selectivity. The conversion of BH3·SMe2 reached 84%, the highest TON of 252 compared to other zinc catalysts was achieved at room temperature and borate ester products at reduction levels of CH3OH were obtained. Magnesium-based hydride complex 5 showed inferior activity for the hydroboration reduction of CO2.

12.
Nanomaterials (Basel) ; 12(8)2022 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-35457950

RESUMO

In the past decade, strong coupling between light and matter has transitioned from a theoretical idea to an experimental reality. This represents a new field of quantum light-matter interaction, which makes the coupling strength comparable to the transition frequencies in the system. In addition, the achievement of multimode strong coupling has led to such applications as quantum information processing, lasers, and quantum sensors. This paper introduces the theoretical principle of multimode strong coupling based on surface plasmons and reviews the research related to the multimode interactions between light and matter. Perspectives on the future development of plasmonic multimode coupling are also discussed.

13.
Materials (Basel) ; 15(18)2022 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-36143599

RESUMO

We investigated, via a phase-field model simulation, the effects of a matrix's properties and a filler's characters on the polytetrafluoroethylene (PTFE) crystal growth process in composites under various supercooling degrees. The results show that the supercooling degree has a deciding influence on the crystal growth process. The intrinsic properties of PTFE polymer, such as anisotropic strength and phase transition latent heat, affect the growth rate, orientation, and interfacial integrity of the crystal trunk and the branching of the PTFE crystal growth process. The factors of the PTFE crystallization process, such as anisotropic strength and phase translation interface thickness, affect the uniformity and crystallization degree of the PTFE crystal. In the composites, the biphasic interface induces the crystal growth direction via the polymer chain segment migration rate, of which the degree depends on the shapes of the filler and the PTFE crystal nucleus. According to the results, choosing the low molecular weight PTFE and mixture filler with various particle sizes and surface curvatures as the raw materials of PTFE-based composites improves the crystallization of the PTFE matrix.

14.
ACS Nano ; 16(10): 16150-16157, 2022 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-36121352

RESUMO

The study of exotic superconductivity in two dimensions has been a central theme in the solid state and materials research communities. Experimentally exploring and identifying exotic, fascinating interface superconductors with a high transition temperature (Tc) are challenging. Here, we report an experimental observation of intriguing two-dimensional superconductivity with a Tc of up to 3.8 K at the interface between a Mott insulator Ti2O3 and polar semiconductor GaN. At the verge of superconductivity, we also observe a striking quantum metallic-like state, demonstrating that it is a precursor to the two-dimensional superconductivity as the temperature is decreased. Our work shows an exciting opportunity to exploit the underlying, emergent quantum phenomena at the heterointerfaces via heterostructure engineering.

15.
Nat Commun ; 13(1): 6593, 2022 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-36329034

RESUMO

Strongly correlated materials often exhibit an electronic phase separation (EPS) phenomena whose domain pattern is random in nature. The ability to control the spatial arrangement of the electronic phases at microscopic scales is highly desirable for tailoring their macroscopic properties and/or designing novel electronic devices. Here we report the formation of EPS nanoscale network in a mono-atomically stacked LaMnO3/CaMnO3/PrMnO3 superlattice grown on SrTiO3 (STO) (001) substrate, which is known to have an antiferromagnetic (AFM) insulating ground state. The EPS nano-network is a consequence of an internal strain relaxation triggered by the structural domain formation of the underlying STO substrate at low temperatures. The same nanoscale network pattern can be reproduced upon temperature cycling allowing us to employ different local imaging techniques to directly compare the magnetic and transport state of a single EPS domain. Our results confirm the one-to-one correspondence between ferromagnetic (AFM) to metallic (insulating) state in manganite. It also represents a significant step in a paradigm shift from passively characterizing EPS in strongly correlated systems to actively engaging in its manipulation.

16.
Nat Commun ; 13(1): 7819, 2022 Dec 19.
Artigo em Inglês | MEDLINE | ID: mdl-36535951

RESUMO

Thermochromic window develops as a competitive solution for carbon emissions due to comprehensive advantages of its passivity and effective utilization of energy. How to further enhance the solar modulation ([Formula: see text]) of thermochromic windows while ensuring high luminous transmittance ([Formula: see text]) becomes the latest challenge to touch the limit of energy efficiency. Here, we show a smart window combining mechanochromism with thermochromism by self-rolling of vanadium dioxide (VO2) nanomembranes to enhance multi-level solar modulation. The mechanochromism is introduced by the temperature-controlled regulation of curvature of rolled-up smart window, which benefits from effective strain adjustment in VO2 nanomembranes upon the phase transition. Under geometry design and optimization, the rolled-up smart window with high [Formula: see text] and [Formula: see text] is achieved for the modulation of indoor temperature self-adapted to seasons and climate. Furthermore, such rolled-up smart window enables high infrared reflectance after triggered phase transition and acts as a smart lens protective cover for strong radiation. This work supports the feasibility of self-rolling technology in smart windows and lens protection, which promises broad interest and practical applications of self-adapting devices and systems for smart building, intelligent sensors and actuators with the perspective of energy efficiency.

17.
Annu Int Conf IEEE Eng Med Biol Soc ; 2021: 2588-2591, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34891783

RESUMO

Cobb angle is the most common quantification of the spine deformity called scoliosis. Recently, automatic Cobb angle estimation has become popular with either semantic segmentation networks or landmark detectors. However, such methods can not perform robustly when some vertebrae have ambiguous appearances in X-ray images. To alleviate the above problem, we propose a multi-task model that simultaneously outputs semantic masks and keypoints of vertebrae. When training this model, we propose a heterogeneous consistency loss function to enhance the consistency between keypoints and semantic masks. Extensive experiments on anterior-posterior (AP) X-ray images from AASCE MICCAI 2019 Challenge demonstrate that our method significantly reduces Cobb angle estimation errors and achieves state-of-the-art performances.Clinical relevance- This work shows that a multi-task model has some potential to measure Cobb angles in more challenging situations, and we can directly integrate it into an auxiliary clinical diagnosis system to assist doctors more effectively for subsequent treatments.


Assuntos
Escoliose , Humanos , Escoliose/diagnóstico por imagem , Coluna Vertebral/diagnóstico por imagem
18.
Annu Int Conf IEEE Eng Med Biol Soc ; 2021: 3061-3065, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34891889

RESUMO

Instrument segmentation is a crucial and challenging task for robot-assisted surgery operations. Recent commonly-used models extract feature maps in multiple scales and combine them via simple but inferior feature fusion strategies. In this paper, we propose a hierarchical attentional feature fusion scheme, which is efficient and compatible with encoder-decoder architectures. Specifically, to better combine feature maps between adjacent scales, we introduce dense pixel-wise relative attentions learned from the segmentation model; to resolve specific failure modes in predicted masks, we integrate the above attentional feature fusion strategy based on position-channel-aware parallel attention into the decoder. Extensive experimental results evaluated on three datasets from MICCAI 2017 EndoVis Challenge demonstrate that our model outperforms other state-of-the-art counterparts by a large margin.


Assuntos
Processamento de Imagem Assistida por Computador , Procedimentos Cirúrgicos Robóticos , Atenção , Aprendizagem , Instrumentos Cirúrgicos
19.
Rev Sci Instrum ; 92(3): 035115, 2021 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-33820007

RESUMO

Due to high hardness and high abrasion, conventional planar polycrystalline diamond compact (PDC) cutters can easily get broken and dull when drilling in (ultra-)deep formations. To enhance the drilling performance, an innovative kind of non-planar PDC cutter, namely, a triangular-shaped PDC cutter, has been developed by altering the 2D planar cutting face into a 3D cutting structure of a triangular trustum of a pyramid. According to the numerical simulation results, the triangular-shaped PDC cutter can easily break hard rocks by a smaller cutting force than the conventional planar PDC cutter. Furthermore, it requires less mechanical specific energy for breaking the same volume of rock than the planar PDC cutter. The triangular-shaped PDC cutter shows great potential in improving the drilling performances of the PDC bit in hard and abrasive formations.

20.
Dalton Trans ; 49(8): 2578-2588, 2020 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-32030388

RESUMO

In this study, Ca4La6-xNdx(SiO4)4(PO4)2O2 (x = 0, 1, 2, 3, 4, 5, and 6) apatites were explored for nuclear waste immobilization, and Nd3+ ions were used as the surrogate of radionuclides (such as Am3+, Cm3+, and Pu3+). The synthesized samples conform to the P63/m (176) symmetry in the hexagonal system according to the characterizations by means of X-ray diffraction, Raman spectra, and Fourier-transform infrared spectra. Rietveld analyses indicate that both Ca2+ and Ln3+ (La, Nd) cations are located at the M4f and M6h sites, which is different from earlier studies. The M6h sites prefer to be occupied by Ln3+ (La, Nd) cations with higher valence. Besides, the content of the impurity phase Ca3(PO4)2 reduces from 2.815 wt% to 0 with the incorporation of Nd3+ ions. These results demonstrate that apatites possess excellent ability to accommodate radionuclides with various valences and radii at the M4f and M6h sites. Moreover, we investigated the thermal expansion behavior by high-temperature X-ray diffraction. There is no phase transformation in the range of 298-1173 K, and the Ca4La6-xNdx(SiO4)4(PO4)2O2 apatites exhibit lower thermal expansion coefficients than other candidates that have been extensively studied. Furthermore, the thermal expansion coefficient gradually decreases with the accommodation of Nd3+ ions. All the results suggest that apatites are promising candidates for nuclear waste immobilization.

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