24 research outputs found

    Formation and Destiny of White Dwarf and Be Star Binaries

    Full text link
    The binary systems consisting of a Be star and a white dwarf (BeWDs) are very interesting.They can originate from the binaries composed of a Be star and a subdwarf O or B star (BesdOBs), and they can merge into red giants via luminous red nova or can evolve into double WD potentially detected by LISALISA mission. Using the method of population synthesis, we investigate the formation and the destiny of BeWDs,and discuss the effects of the metallicity (ZZ) and the common envelope evolution parameters. We find that BesdOBs are significant progenitors of BeWDs. About 30\% (Z=0.0001Z=0.0001)-50\% (Z=0.02Z=0.02) of BeWDs come from BesdOBs. About 60\% (Z=0.0001Z=0.0001) -70\% (Z=0.02Z=0.02) of BeWDs turn into red giants via a merger between a WD and a non-degenerated star. About 30\% (Z=0.0001Z=0.0001) -40\% (Z=0.02Z=0.02) of BeWDs evolve into double WDs which are potential gravitational waves of LISALISA mission at a frequency band between about 3×10−33\times10^{-3} and 3×10−23\times10^{-2} Hz. The common envelope evolution parameter introduces an uncertainty with a factor of about 1.3 on BeWD populations in our simulations.Comment: 17 pages, 12 figures, 2 table, accepted for publication in RA

    An Innovative Continuing Nursing Education Program Targeting Key Geriatric Conditions for Hospitalized Older People in China

    Get PDF
    This article under embargo for 18 months from the date of publication due to publisher copyright restrictions. "This is an Accepted Manuscript of an article published by Taylor & Francis i nEducational Gerontology on 23 May 2013, available online: http://wwww.tandfonline.com/10.1080/03601277.2012.704233."A lack of knowledge in registered nurses about geriatric conditions is one of major factors that contribute to these conditions being overlooked in hospitalised older people. In China an innovative geriatric continuing nursing education program aimed at developing registered nurses’ understanding of the complex care needs of hospitalised older people with common geriatric conditions were conducted and evaluated. The program consisted of didactic sessions focused on evidence-based practice and unfolding case study designed to simulate the care trajectory of an older person with a hip fracture and key geriatric conditions. Findings from the program evaluations revealed a significant increase in attitudes towards older people and knowledge concerning common geriatric conditions. The satisfactory rate ranked by program participants was 90%. The study therefore drew the conclusion that effective geriatric continuing nursing education should target participants’ learning needs, support evidence-based practice and engage participants in active learning

    Tetrahydroisoquinoline N-methyltransferase from <i>Methylotenera</i> Is an Essential Enzyme for the Biodegradation of Berberine in Soil Water

    No full text
    Berberine (BBR), a Chinese herbal medicine used in intestinal infection, has been applied as a botanical pesticide in the prevention of fungal disease in recent years. However, its degradation in the environment remains poorly understood. Here, we investigated BBR’s degradation in soil water from different sources accompanied by its effect on bacterial diversity. Our results indicated that BBR was only degraded in soil water, while it was stable in tap water, river water and aquaculture water. Bacterial amplicon results of these samples suggested that the degradation of BBR was closely related to the enrichment of Methylotenera. To reveal this special relationship, we used bioinformatics tools to make alignments between the whole genome of Methylotenera and the pathway of BBR’s degradation. An ortholog of Tetrahydroisoquinoline N-methyltransferase from plant was discovered only in Methylotenera that catalyzed a crucial step in BBR’s degradation pathway. In summary, our work indicated that Methylotenera was an essential bacterial genus in the degradation of BBR in the environment because of its Tetrahydroisoquinoline N-methyltransferase. This study provided new insights into BBR’s degradation in the environment, laying foundations for its application as a botanical pesticide

    Saprophytic <i>Bacillus</i> Accelerates the Release of Effective Components in Agarwood by Degrading Cellulose

    No full text
    The value of Agarwood increases with time due to the gradual release of its major components, but the mechanism behind this remains unclear. Herein we reveal that the potential driving force of this process is the degradation of cellulose in Agarwood by its saprophytic Bacillus subtilis. We selected 10-year-old Agarwood from different places and then isolated the saprophytic bacteria. We confirmed these bacteria from different sources are all Bacillus and confirmed they can degrade cellulose, and the highest cellulase activity reached 0.22 U/mL. By co-cultivation of the bacterium and Agarwood powder, we found that three of the strains could release the effective components of Agarwood, while they had little effect in increasing the same components in living Aquilaria sinensis. Finally, we demonstrated that these saprophytic Bacillus subtilis have similar effects on Zanthoxylum bungeanum Maxim and Dalbergiaod orifera T. Chen, but not on Illicium verum Hook. f, Cinnamomum cassia Presl and Phellodendron chinense Schneid. In conclusion, our experiment revealed that the saprophytic Bacillus release the effective components of Agarwood by degrading cellulose, and we provide a promising way to accelerate this process by using this bacterial agent

    Progressive Failure and Acoustic Emission Characteristics of Red Sandstone with Different Geometry Parallel Cracks under Uniaxial Compression Loading

    No full text
    The geometric distribution of initial damages has a great influence on the strength and progressive failure characteristics of the fractured rock mass. Initial damages of the fractured rock were simplified as parallel cracks in different geometric distributions, and then, the progressive failure and acoustic emission (AE) characteristics of specimens under the uniaxial compression loading were analyzed. The red sandstone (brittle materials) specimens with the parallel preexisting cracks by water jet were used in the tests. The energy peak and stress attenuation induced by the energy release of crack initiation were intuitively observed in the test process. Besides, three modes of rock bridge coalescence were obtained, and wing crack was the main crack propagation mode. The wing crack and other cracks were initiated in different loading stages, which were closely related to the energy level of crack initiation. The propagation of wing crack (stable crack) consumed a large amount of energy, and then, the propagation of shear crack, secondary crack, and anti-wing crack (unstable crack) was inhibited. The relationship between the crack propagation mode and the geometric distribution of existing cracks in the specimen was revealed. Meanwhile, the strength characteristic and failure mode of fractured rock with the different geometric distributions of preexisting crack were also investigated. The energy evolution characteristics and crack propagation were also analyzed by numerical modeling (PFC2D)

    High-Quality Fiber Bragg Gratings Inscribed by Femtosecond Laser Point-by-Point Technology

    No full text
    We experimentally studied the inscription of fiber Bragg gratings by using femtosecond (fs) laser point-by-point (PbP) technology. The effects of the focusing geometry, grating order, laser energy and grating length on the spectral characteristics of the PbP FBG were investigated. After optimizing these parameters, a high-quality first-order PbP FBG with a reflectivity &gt; 99.9% (i.e., Bragg resonance attenuation of 37.7 dB) and insertion loss (IL) of 0.03 dB was successfully created. Moreover, taking advantage of the excellent flexibility of the fs laser PbP technology, high-quality FBGs with various Bragg wavelengths ranging from 856 to 1902.6 nm were inscribed. Furthermore, wavelength-division-multiplexed (WDM) FBG arrays consisting of 10 FBGs were rapidly constructed. Additionally, a Fabry-Perot cavity was realized by using two high-quality FBGs, and its birefringence could be reduced from 3.04 × 10−5 to 1.77 × 10−6 by using a slit beam shaping-assisted femtosecond laser PbP technology. Therefore, such high-quality FBGs are promising to improve the performance of optical fiber sensors, lasers and communication devices

    Real-time energy management for the integrated heat and power system using approximate dynamic programming

    No full text
    This paper proposes the real-time energy management for the integrated heat and power system (IHPS) based on the approximate dynamic programming (ADP) algorithm. Considering the energy storage and the heat loss in the pipelines, the multi-time period optimization is formulated. The uncertainties brought by the wind power, electricity price, electric load, and heat load, are also taken into account. The proposed ADP algorithm can obtain the near-optimal solution by recursively solving the Bellman\u27s equation, meanwhile update the real-time forecast information to improve the optimality under the stochastic environment. Simulation results demonstrate the superiority of the ADP algorithm compared to existing real-time decision-making methods such as model predictive control (MPC) in both deterministic and stochastic cases

    Targeting the Endocannabinoid/CB1 Receptor System For Treating Major Depression Through Antidepressant Activities of Curcumin and Dexanabinol-Loaded Solid Lipid Nanoparticles

    No full text
    Background/Aims: This study investigated the underlying mechanisms of the antidepressant effects of curcumin and dexanabinol-loaded solid lipid nanoparticles in corticosterone-induced cell and mice depression models. Methods: Curcumin and dexanabinol-loaded solid lipid nanoparticles (Cur/SLNs-HU-211) were synthesized via an emulsifcation and low-temperature solidification method. Antidepressant activities of nanoparticles in a corticosterone-induced major depression model were investigated by MTT assay, cellular uptake by flow cytometry, behaviour by Forced Swimming Test and rotarod test, neurotransmitters by High Performance Liquid Chromatography, Western blotting, qPCR and immunofluorescence. Results: Treatment with Cur/SLNs-HU-211 induced greater dopamine (DA)/5-hydroxytryptamine (5-HT) release with reduced corticosterone-induced apoptotic cell death in PC12 cells. Additionally, in vivo Cur/SLNs-HU-211 significantly induced recovery from depressive behaviour with increased DA/5-HT levels, CB1 mRNA levels and CB1, p-MEK1 and p-ERK1/2 protein expression levels in the hippocampus and striatum. Cur/SLNs-HU-211 improved CB1 expression and inspired the proliferation of astrocytes in the hippocampus and striatum, exerted neuroprotective effects by preventing corticosterone -induced BDNF/NeuN expression reduction. Conclusion: Our study implies that Cur/SLNs-HU-211 may be a useful approach for treatment of major depression

    Highly Sensitive Temperature Sensor Based on Cascaded Polymer-Infiltrated Fiber Mach–Zehnder Interferometers Operating near the Dispersion Turning Point

    No full text
    High-accuracy temperature measurement plays a vital role in biomedical, oceanographic, and photovoltaic industries. Here, a highly sensitive temperature sensor is proposed and demonstrated based on cascaded polymer-infiltrated Mach–Zehnder interferometers (MZIs), operating near the dispersion turning point. The MZI was constructed by splicing a half-pitch graded index fiber (GIF) and two sections of single-mode fiber and creating an inner air cavity based on femtosecond laser micromachining. The UV-curable polymer-infiltrated air cavity functioned as one of the interference arms of MZI, and the residual GIF core functioned as the other. Two MZIs with different cavity lengths and infiltrated with the UV-curable polymers, having the refractive indexes on the different sides of the turning point, were created. Moreover, the effects of the length and the bending way of transmission SMF between the first and the second MZI were studied. As a result, the cascaded MZI temperature sensor exhibits a greatly enhanced temperature sensitivity of −24.86 nm/°C based on wavelength differential detection. The aforementioned result makes it promising for high-accuracy temperature measurements in biomedical, oceanographic, and photovoltaic applications
    corecore