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Camellia oleifera is an important edible oil woody plant in China. Anthracnose is a serious disease of C. oleifera, causing severe economic losses and posing a huge threat to the C. oleifera industry. The fungi Colletotrichum siamense is one of the main pathogens causing anthracnose of C. oleifera. In this study, antifungal activity of microorganisms isolated from garbage enzyme against C. siamense were investigated for the first time. 8 strains were isolated and purified from garbage enzyme. By morphological observation, gene sequence analysis, among the strains, 4 isolates were identified as Trichoderma harzianum and 4 isolates were identified as Bacillus subtilis. The result showed that 8 isolates displayed a relatively good potential on inhibiting the mycelial growth in C. siamense, but T. harzianum was more effective than B. subtilis as a biocontrol agent, with the best efficiency of 76.5%. In the vitro treatments, the combination of T. harzianum and B. subtilis were the most effective treatments in reducing the incidence and severity of anthracnose in C.oleifera, with the highest control efficiency of 77.56%. It can be concluded that T. harzianum and B. subtilis are promising biocontrol agents to manage anthracnose. These promising results provided valuable information on using garbage enzyme of wastes as a new source of antagonists to control fungi disease. [ABSTRACT FROM AUTHOR]

The response of a ballistic two-dimensional electron gas (2DEG) confined to a Hall cross and subjected to a locally inhomogeneous magnetic field which is created by two parallel or antiparallel magnetized cylindrical dots deposited above the 2DEG is investigated. The Hall and bend resistances are calculated as a function of the magnetization of the magnetic dots for different positions of the dots on the Hall bar. The Hall and bend resistances are different for parallel and antiparallel magnetized dots and depend on the relative position of the magnetic dots on the Hall bar. [ABSTRACT FROM AUTHOR]

The leaching kinetics of 20CaO·13Al2O3·3MgO·3SiO2(Q phase) was studied in this paper. The effects of agitation speed, leaching temperature, concentration of sodium carbonate, particle size and liquid–solid ratio on alumina leaching ratio of Q phase were investigated. The results indicate that the agitation speed did not influence alumina leaching ratio when it was higher than 400 r min−1, and the effect of liquid film diffusion on the leaching process was eliminated. The alumina leaching ratio would not increase by changing the liquid–solid ratio, when the concentration of sodium carbonate was excessive. The leaching process of Q phase was better as both the temperature and the concentration of sodium carbonate were higher and the particle size was smaller. The effect of concentration of sodium carbonate on alumina leaching ratio was not obvious. The leaching kinetics followed the shrinking unreacted core model, the reaction order of leaching process of Q phase was 0.47, and it can be described by surface chemical reaction. The activation energy was 41.63 ± 10 kJ mol−1, and the frequency factor was 1.472 × 103. [ABSTRACT FROM AUTHOR]

Surface frosting from atmospheric humidity under natural convection is encountered in conventional refrigeration systems, cryogenic surgery, and cryogenic stress relief of die casting metal forming applications. To advance the predictability of frost initiation and formation processes, this study reports a microscopic analysis of frost growth on a flat surface during the onset period of freezing when subcooled droplets are formed and changed to the ice phase. The onset of freezing is quantified by the mean droplet size and ice particle fractions at a critical time (when water droplet freezing point is reached) with the aid of a video microscope. All early-stage frost formulation model with effective parameters is demonstrated to provide the important information for the transition to the steady-growth model. The model results are compared with the measured air-frost surface temperatures at different cooling and ambient boundary conditions, using holographic interferometry. The comparison between the model prediction and experimental results demonstrates the sensitivity of effective parameters in simulating the frost thickness and air-frost interface temperature. [ABSTRACT FROM AUTHOR]

A mean-field-type model was established to describe the concentration of point defects in binary NiAl by taking into account the effects of crystal expansion and off-stoichiometry. Different from some recent studies, this analysis shows that constitutional vacancies are present only in Al-rich NiAl at T = 0 K but that the vacancy concentration decreases with increasing temperature until diffusion is activated and thereafter becomes nearly independent of temperature. Such vacancy formation behaviour in Al-rich NiAl belongs to the category of metastable constitutional type according to a method of classifying vacancy formation in B2 crystals proposed in this letter. [ABSTRACT FROM AUTHOR]

I-V and C-V curves of metal-semiconductor-metal ultraviolet detector grown with AlGaN/GaN multi-quantum-well (MQW) interlayer are found to oscillate with applied bias voltage. A simple model is proposed to explain the oscillation phenomena of both curves. Resonant tunneling of polarization induced charges through the barriers of the nitride based MQW structure terminated with back-to-back configuration Schoktty contacts may play a key role in the oscillating phenomena. [ABSTRACT FROM AUTHOR]

Here we report a non-toxic β-type titanium alloy exhibiting unstable elastic and plastic deformation behavior. Elastic instability leads to remarkable elastic softening, i.e., the decrease of incipient Young’s modulus with slight pre-straining. In spite of partial recovery during room-temperature aging, a stable modulus of 33 GPa matching that of human bone can be maintained. Plastic instability causes highly-localized deformation which is very effective in grain refinement but contributes little to strength. We thus obtain soft nanostructured metallic materials (NMMs): The flow stress increases by only ∼5.5% as coarse grains are reduced to below 50 nm, in contrast with several times increase for previously-reported NMMs. [ABSTRACT FROM AUTHOR]

We investigate the influence of an external perpendicular magnetic field on the lowest-energy states of an electron bound to a donor which is located near a semiconductor-metal interface. The problem is treated within the effective mass approach and the lowest-energy states are obtained through (1) the "numerically exact" finite element method, and (2) a variational approach using a trial wave function where all image charges that emerge due to the presence of the metallic gate are taken into account. The trial wave functions are constructed such that they reduce to an exponential behavior for sufficiently small magnetic fields and become Gaussian for intermediate and large magnetic fields. The average electron-donor distance can be controlled by the external magnetic field. We find that the size of the 2pz state depends strongly on the magnetic field when the donor is close to the interface, showing a nonmonotonic behavior, in contrast with the ground and the other excited states. [ABSTRACT FROM AUTHOR]

Yunnan snub-nosed monkeys ( Rhinopithecus bieti) are 1 of 3 snub-nosed monkey species endemic to China. Only ca. 1500 individuals remain in high-altitude forests 3000–4500 m above sea level on the Tibetan Plateau, making them the nonhuman primate living at the highest known elevation. It is one of the most endangered 25 primate species in the world. Proper knowledge of the population genetics and social system of Rhinopithecus bieti will contribute to more appropriate conservation management decisions. Cross-species amplification of human microsatellite loci has facilitated analysis of the population genetics and reproductive strategies of various primate species. We screened 72 human-derived markers to assess their utility in Yunnan snub-nosed monkeys. Thirteen of them produced reliable results and exhibited moderate levels of polymorphism. [ABSTRACT FROM AUTHOR]

A two-phase, non thermal equilibrium-based model is applied to the numerical simulation of laminar flow and heat transfer characteristics of suspension with microsize phase-change material (PCM) particles in a microchannel. The model solves the conservation of mass, momentum, and thermal energy equations for liquid and particle phases separately. The study focuses on the parametric study of optimal conditions where heat transfer is enhanced with an increase in fluid power necessary for pumping the two-phase flow. The main contribution of PCM particles to the enhancement of heat transfer in a microsize tube is to increase the effective thermal capacity and utilize the latent heat effect under the laminar flow condition. An effectiveness factor εeff is defined to evaluate the heat transfer enhancement compared to the single-phase flow heat transfer and is calculated under different wall heat fluxes and different Reynolds numbers. The comparison is also made to evaluate the performance index, i.e., the ratio of total heat transfer rate to fluid flow power (pressure drop multiplied by volume flow rate) between PCM suspension flow and pure water single-phase flow. The results show that for a given Reynolds number, there exists an optimal heat flux under which the εeff value is the greatest. In general the PCM suspension flow with phase change has a significantly higher performance index than the pure-fluid flow. The comparison of the model simulation with the limited experimental results for a MCPCM suspension flow in a 3 mm dia tube reveals the sensitivity of wall temperature distribution to the PCM supply temperature and the importance of characterizing the phase change region for a given tube length. [ABSTRACT FROM AUTHOR]

The objective of the study described here is to fundamentally elucidate the biological response of 3D printed Ti-6Al-4V alloy mesh structures that were surface modified to introduce titania nanotubes with an average pore size of ∼80 nm via an electrochemical anodization process from the perspective of enhancing bioactivity. The bioactivity of the mesh structures were analyzed through immersion test in simulated body fluid, which confirmed the nucleation and growth of fine globular nanoscale apatite on the nanoporous titania-modified (anodized) mesh structure surface, and agglomerated apatite with fine flakes of apatite crystals on as-fabricated mesh structure surface, that were rich in calcium and phosphorous. The cellular activity of bioactive anodized mesh structure was explored in terms of cell–material interactions involving adhesion, proliferation, synthesis of extracellular and intracellular proteins, differentiation, and mineralization. Cells adhered with a sheet-like morphology on as-fabricated mesh structure, whereas, on anodized mesh structure, numerous filopodia-like cellular extensions interacting with nanotube pores were observed. The formation of a bioactive nanoscale apatite, cell–nanotube interactions as imaged via electron microscopy, higher expression of proteins (actin, vinculin, fibronectin, and alkaline phosphatase (ALP)), and calcium content points toward the determining role of anodized mesh structure in modulating osteoblasts functions. The unique combination of nanoporous bioactive titania and interconnected porous architecture of anodized titanium alloy mesh structure provided a multimodal roughness surface ranging from nano to micro to macroscale, which helps in attaining strong primary and secondary fixation of the implant device along with the pathway for supply of nutrients and oxygen to cells and tissue. [ABSTRACT FROM AUTHOR]

In this letter, a torsional optomechanical resonator for torque sensing and torsional mechanical frequency mixing is experimentally demonstrated. The torsional mechanical resonator is embedded into a split optical racetrack resonator, which provides high sensitivity in measuring torsional mechanical motion. Using this high sensitivity, torsional mechanical frequency mixing is observed without regenerative mechanical motion. The displacement noise floor of the torsional mechanical resonator is 50 fm/Hz0.5, which demonstrates a resonant torque sensitivity of 3.58x10-21Nm/Hz0.5. This demonstration will benefit potential applications for on-chip RF signal modulation using optical mechanical resonators. [ABSTRACT FROM AUTHOR]

We report a real-time method to determine the size, i.e. diameter, and refractive index of single gold nanoparticles using an optofluidic chip, which consists of a quasi-Bessel beam optical chromatography. The tightly focused (~ 0.5 μm) quasi-Bessel beam with low divergence (NA ~ 0.04) was used to trap sub-100 nm gold nanoparticles within a long trapping distance of 140 μm. In the experiment, 60 to 100 nm gold nanoparticles were separated efficiently with at least 18 μm. The diameter and refractive index (real and imaginary) of single gold nanoparticles were measured at high resolutions with respect to the trapping distance, i.e. 0.36 nm/μm, 0.003/μm and 0.0016/μm, respectively. [ABSTRACT FROM AUTHOR]

An optofluidic chip is demonstrated in experiments for high-resolution and multi-range particle separation through the optically-induced microscopic vibration effect, where nanoparticles are trapped in loosely overdamped optical potential wells created with combined optical and fluidic constraints. It is the first demonstration of separating single nanoparticles with diameters ranging from 60 to 100 nm with a resolution of 10 nm. Nanoparticles vibrate with an amplitude of 3–7 μm in the loosely overdamped potential wells in the microchannel. The proposed optofluidic device is capable of high-resolution particle separation at both nanoscale and microscale without reconfiguring the device. The separation of bacteria from other larger cells is accomplished using the same chip and operation conditions. The unique trapping mechanism and the superb performance in high-resolution and multi-range particle separation of the proposed optofluidic chip promise great potential for a diverse range of biomedical applications. [ABSTRACT FROM AUTHOR]

We describe here the combined efforts of engineering and biological sciences as a systemic approach to fundamentally elucidate osteoblast functions in functionally graded Ti-6Al-4 V mesh structures in relation to uniform/monolithic mesh arrays. First, the interconnecting porous architecture of functionally graded mesh arrays was conducive to cellular functions including attachment, proliferation, and mineralization. The underlying reason is that the graded fabricated structure with cells seeded from the large pore size side provided a channel for efficient transfer of nutrients to other end of the structure (small pore size), leading to the generation of mineralized extracellular matrix by differentiating pre-osteoblasts. Second, a comparative and parametric study indicated that gradient mesh structure had a pronounced effect on cell adhesion and mineralization, and strongly influenced the proliferation phase. High intensity and near-uniform distribution of proteins (actin and vinculin) on struts of the gradient mesh structure (cells seeded from large pore side) implied signal transduction during cell adhesion and was responsible for superior cellular activity, in comparison to the uniform mesh structure and non-porous titanium alloy. Cells adhered to the mesh struts by forming a sheet, bridging the pores through numerous cytoplasmic extensions, in the case of porous mesh structures. Intercellular interaction in porous structures provided a pathway for cells to communicate and mature to a differentiated phenotype. Furthermore, the capability of cells to migrate through the interconnecting porous architecture on mesh structures led to colonization of the entire structure. Cells were embedded layer-by-layer in the extracellular matrix as the matrix mineralized. The outcomes of the study are expected to address challenges associated with the treatment of segmental bone defects and bone-remodeling through favorable modulation of cellular response. Moreover, the study provides a foundation for a new branch of functionally graded materials with interconnected porous architecture. [ABSTRACT FROM AUTHOR]

Titanium and titanium alloys with open cellular structures and foams possess low Young's modulus matching to human bone and the capability to provide space for bone tissue ingrowth to reach a better fixation, which have been thought as a good choice for the replacement of commercial dense implants. However, currently developed fabrication methods of titanium cellular alloys, such as powder sintering, reveal shortcomings like the low porosity and poor control over the size, shape and distribution of the pores. Recently, additive manufacturing using the electron beam melting method has been applied successfully to fabricate titanium cellular meshes and foams. Compared to other reported methods, this technique has the advantages of accurate control of internal pore architectures and complex cell shapes. In the present paper, the authors briefly review the fabrication, Young's modulus, mechanical properties and biocompatibility of Ti–6Al–4V cellular structures fabricated by electron beam melting techniques, along with future development trends. [ABSTRACT FROM AUTHOR]

The low quantum yield (~10-5) has restricted practical use of photoluminescence (PL) from MoS2 composed of a few layers, but the quantum confinement effects across two-dimensional planes are believed to be able to boost the PL intensity. In this work, PL from 2 to 9 nm MoS2 quantum dots (QDs) is excluded from the solvent and the absorption and PL spectra are shown to be consistent with the size distribution. PL from MoS2 QDs is also found to be sensitive to aggregation due to the size effect. [ABSTRACT FROM AUTHOR]

Objective Acquired aplastic anaemia ( AA) is a T-cell-mediated, organ-specific autoimmune disease characterized by haematopoietic stem cell destruction in the bone marrow. The exact molecular mechanism of T-cell trafficking into the bone marrow is unclear in AA. Very late activation antigen-4 ( VLA-4) and CX3C chemokine receptor 1 (CX3CR1) play active roles in many autoimmune diseases. Therefore, we investigated whether VLA-4 and CX3CR1 also contribute to T-cell migration into the bone marrow in acquired AA. Design, setting and subjects Expression levels of CX3CR1 and VLA-4 and their ligands [fractalkine (CX3CL1) and vascular cell adhesion molecule-1 (VCAM-1)] were examined in 63 patients with AA and 21 healthy control subjects. T-cell chemotaxis and adhesion were analysed in 17 patients with severe AA. We also prospectively evaluated the expression pattern of CX3CR1 during treatment with antithymocyte globulin plus cyclosporine in 11 patients with severe AA. Results The proportion of peripheral and bone marrow CD4+ and CD8+ T cells expressing CX3CR1 and the level of CX3CL1 was increased in patients with AA. However, there was no significant difference in VLA-4 expression or VCAM-1 levels. Functional studies demonstrated that chemotaxis towards autologous bone marrow plasma or soluble CX3CL1 was significantly higher in T cells from AA patients and could be blocked by CX3CR1 inhibitors. CX3CR1-mediated T-cell adhesion was also upregulated in these patients. The expression of CX3CR1 was associated with the efficacy of immunosuppressive therapy. Conclusion The present findings demonstrate that CX3CR1 plays a pivotal role in recruitment of T cells into the bone marrow in acquired AA and is a potential therapeutic target for treatment of this disorder. [ABSTRACT FROM AUTHOR]

This letter presents a novel MEMS-based multifunction-integrated optical device capable of performing as variable optical power splitter (VOPS), optical switch (OS), and variable optical attenuator (VOA). The device manipulates the light with a binary-slope mirror driven by compound electrostatic actuator. The optical models for splitting and attenuating are investigated, respectively. Ball-lensed fibers are assembled with the device to achieve high coupling efficiency in this work. Measurements reveal that the excess loss of the device is less than 3 dB, and the controllable attenuation range is up to 39 dB. Moreover, polarization-dependent loss is less than 0.7 dB. © 2008 Wiley Periodicals, Inc. Microwave Opt Technol Lett 50: 2185–2189, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.23603 [ABSTRACT FROM AUTHOR]

Phase transformations and mechanical properties of both Ti–29Nb–13Ta–4·6Zr and Ti–39Nb–13Ta–4·6Zr (wt–%) alloys were investigated. The microstructure of the 29Nb alloy is sensitive to solution and aging treatment. Ice water quenching from the solution treatment temperature resulted in (β+α") microstructure but air or furnace cooling led to a mixture of (β+ω). The formation of the orthorhombic α" martensite thus suppresses ω formation in the ice water quenched 29Nb alloy. Cooling rate from the solution treatment temperature also has a significant effect on the formation of α and ω phases during subsequent isothermal aging below the ω start temperature: slow cooling enhances ω but depresses α formation. This cooling rate dependence of aged microstructure was attributed to α" martensite acting as precursor of the α phase, thus providing a low energy path to the precipitation of a at the expense of ω. Phase transformation in the 39Nb alloy is more sluggish than that in the 29Nb alloy, owing to the presence of the higher content of β stabiliser Nb. For the 29Nb alloy, Young's modulus and mechanical properties are sensitive to the fraction of phases, and change significantly during aging, in contrast with the 39Nb alloy. [ABSTRACT FROM AUTHOR]

Drosophila melanogaster is a proven model system for many aspects of human biology. Here we present a two-hybrid-based protein-interaction map of the fly proteome. A total of 10,623 predicted transcripts were isolated and screened against standard and normalized complementary DNA libraries to produce a draft map of 7048 proteins and 20,405 interactions. A computational method of rating two-hybrid interaction confidence was developed to refine this draft map to a higher confidence map of 4679 proteins and 4780 interactions. Statistical modeling of the network showed two levels of organization: a short-range organization, presumably corresponding to multiprotein complexes, and a more global organization, presumably corresponding to intercomplex connections. The network recapitulated known pathways, extended pathways, and uncovered previously unknown pathway components. This map serves as a starting point for a systems biology modeling of multicellular organisms, including humans. [ABSTRACT FROM AUTHOR]

Although stress-induced martensitic transformation accelerates grain refinement during plastic deformation, it results in serious damage to recoverable elasticity and ductility of severely cold-rolled multifunctional titanium alloys. Here, large-scale nonlinear elasticity and high ductility were achieved simultaneously in an ultrafine-grained Ti–Nb–Zr–Sn alloy by severe warm rolling at 473 K to suppress the martensitic transformation from the β to the α″ phase. These results suggest that high strength can be attained in nonlinear elastic titanium alloys by improving the stability of the β phase with body-centered-cubic crystal structure through both composition design and grain refinement. [ABSTRACT FROM AUTHOR]

In this letter, we report the experimental demonstration of a dissipative self-sustained optomechanical resonator on a silicon chip by introducing dissipative optomechanical coupling between a vertically offset bus waveguide and a racetrack optical cavity. Different from conventional blue-detuning limited self-oscillation, the dissipative optomechanical resonator exhibits self-oscillation in the resonance and red detuning regime. The anti-damping effects of dissipative optomechanical coupling are validated by both numerical simulation and experimental results. The demonstration of the dissipative self-sustained optomechanical resonator with an extended working range has potential applications in optomechanical oscillation for on-chip signal modulation and processing. [ABSTRACT FROM AUTHOR]

A novel microelectromechanical system capacitive pressure sensor with two wings, which amplify the mechanical deformation of the pressure sensing diaphragm and increase the sensor's sensitivity, is presented. This seesaw structure is available for both single and differential capacitive pressure sensors. To verify this design, a single capacitive pressure sensor is manufactured based on silicon on a insulator (SOI) wafer. The test result shows that this pressure sensor has a sensitivity of 7.75 fF/kPa. [ABSTRACT FROM AUTHOR]