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The synthesis, structure, and properties of pyrene-based conformationally adaptive macrocycles are described. This new type of conformationally adaptive macrocycle was constructed through Perkin reaction, followed by imidization. By changing the condensation partner as the linking unit, a family of conjugated macrocycles with different sizes of the cavity was synthesized, which provide a simple and modular synthetic strategy towards the conformationally adaptive macrocycles. Furthermore, the macrocycles provide two well-defined conformations through flipping pyrene subunit, which were unambiguously determined by single-crystal X-ray diffraction analysis. The conformational interconversion barrier was determined by density functional theory (DFT) calculations. This new macrocycle also demonstrated unique properties, such as vapochromic behavior and aggregation emission enhancement effect. Furthermore, we have also investigated the effect of the linker on the shape and photophysical properties of the resulting macrocyclic products.

There exists a kind of complex periodic motion caused by the short-period error such as the pitch deviation, tooth surface crack, and so on, in the gear transmission system. It affects the transmission stationary of the system. This complex periodic motion is defined as the neighboring periodic motion in this paper. Its identification methods are proposed by using the multi-time scale Poincare mapping sections. The nonlinear dynamics model of spur gear pair considering pitch deviation under multi-state meshing is introduced. The neighboring periodic motion of the system under different parameters is analyzed according to the proposed identification methods. The multi-stable motion of the spur gear pair with short-period error is explored by analysis methods of nonlinear dynamics. Results show that the short-period error leads to the nonstationary transmission of spur gear pair. The periodic motion of the system shows a long-period motion in the micro-time scale due to the effect of the short-period error. The actual periodic number of the system motion is the number of mapping points obtained in the macro-time scale. The number of mapping points in micro-time scale illustrates point clusters. The number of phase trajectory in micro-time scale displays lines clusters. The short-period error affects the range of parameters for multi-stable motion in spur gear pair. These identification and analysis methods provide a theoretical basis for investigation of the neighboring periodic motion in nonlinear systems.

Graphite as a promising anode candidate of K-ion batteries (KIBs) has been increasingly studied currently, but corresponding rate performance and cycling stability are usually inferior to amorphous carbon materials. To protect the layer structure and further boost performance, tempura-like carbon/carbon nanocomposite of graphite@pitch-derived S-doped carbon (G@PSC) is designed and prepared by a facile and low-temperature modified molten salt method. This robust encapsulation structure makes their respective advantages complementary to each other, showing mutual promotion of electrochemical performances caused by synergy effect. As a result, the G@PSC electrode is applied in KIBs, delivering impressive rate capabilities (465, 408, 370, 332, 290, and 227 mA h g−1 at 0.05, 0.2, 0.5, 1, 2, and 5 A g−1) and ultralong cyclic stability (163 mA g−1 remaining even after 8000 cycles at 2 A g−1). On basis of ex-situ studies, the sectionalized K-storage mechanism with adsorption (pseudocapacitance caused by S doping)-intercalation (pitch-derived carbon and graphite) pattern is revealed. Moreover, the exact insights into remarkable rate performances are taken by electrochemical kinetics tests and density functional theory calculation. In a word, this study adopts a facile method to synthesize high-performance carbon/carbon nanocomposite and is of practical significance for development of carbonaceous anode in KIBs.

Drive-side teeth engaging, tooth disengagement and back-side teeth contacting are three meshing states of the spur gear pair. The influence of different meshing states on system safety is different. The safety performances of the system are classified into three safety levels, i.e., safe, quasi-safe and unsafe according to the influence of the meshing state. Three safety domains corresponding to three safety levels are established, respectively. The evolutionary mechanism of the system meshing safety performance is researched in the established safety domain. Multi-initial values bifurcation diagrams and the corresponding top Lyapunov exponents (TLE) of the spur gear pair considered the multiple meshing states are numerically calculated by the 4-order Runge–Kutta method in the C program. The bifurcation & safety dendrograms are constructed to analyze the transition process of the safety performance and the transition mechanism from safe to unsafe. The global integrity measure and integrity factor of the co-existing attraction domains in the safety basins are calculated to identify properly the erosion due to the meshing frequency and damping. It is determined that the safety performance of the system is changed by two patterns. One is the combined action of the bifurcation and varying with the relative displacement amplitude caused by the motion sensitive parameters. The other is one-to-two bifurcation caused by the sensitive parameters of the meshing state. The results provide a theoretical basis for the prediction and control of the meshing state and unsafe performance of the gear pair.

Teeth disengaging or back-side teeth meshing induced by backlash reduces the transmission quality and dynamic performance of gear systems, and accurate interpretation of multi-state meshing behavior can provide guidance for structural optimization and performance evaluation. Therefore, the multi-state meshing behavior of the gear system is elaborated. A new nonlinear dynamic model of a spur gear system with five-state meshing behavior is proposed based on time-varying backlash and contact ratio. The time-varying meshing stiffness and time-varying backlash considering the elastic contact of gear teeth, gear temperature rise and lubrication are included in the model. The five-state meshing behavior is clearly characterized by constructing five Poincaré maps, and its generation mechanism is studied using dynamic meshing force time history, teeth relative displacement time history and phase portrait. The bifurcation and evolution of five-state meshing behavior are analyzed under the effects of load factor, meshing frequency and error coefficient. The results show that the mutation in the direction of dynamic meshing force leads to teeth disengaging and back-side single or double teeth contact, forming multi-state meshing behavior. Bifurcation caused by parameter changes greatly affects the evolution of five-state meshing behavior, particularly grazing bifurcation can decrease the number of teeth disengagement. Chaotic behavior or trajectory expansion inspires multi-state meshing vibration of the system. Previous gear system models could not reveal these phenomena due to ignoring the multi-state meshing behavior.

Backlash-induced variations may lead to teeth separation and back-side tooth mesh in lightly loaded geared drive. Effects of teeth separation and back-side tooth mesh are considered. The dynamic model of a spur gear pair under multi-state meshing conditions such as teeth separation, drive- and back-side tooth mesh is established based on the gear transmission principle and forces acting on teeth. Time-varying meshing stiffness, time-varying friction, load distribution, comprehensive transmission error and backlash are included in the model. Variations of the dynamic meshing force of the system under different meshing states are analyzed numerically. The dynamic meshing force affects the meshing state of the system significantly. Furthermore, the effects of load, backlash and comprehensive transmission error on meshing states and vibro-impact properties of the system are studied by defining three different Poincare maps, where bifurcation diagrams, top Lyapunov exponent diagrams (TLE), phase portraits are used. Results indicate that the complicated phenomena such as drive-side impact, teeth separation and back-side impact gradually occur with the decrease of the load or the increase of the comprehensive error. However, these phenomena always exist with the increase in backlash. This study provides a theoretical reference for the optimization of gears.

UV-B radiation is an increasing threat to aquatic organisms and also a potential driving force for zooplankton population dynamics. To explore the ecological effects of UVR on rotifers and the responses of antioxidant system against UVR, the acute lethal effects, the life history strategies, population growth, and antioxidant enzyme activities were assessed in the Bdelloid Rotaria rotatoria after exposure to UV-B radiation. The results indicated that the persistence of tolerance in rotifer to stress was playing a more vital role than the radiation dose in survival. The larger the culture volume, the weaker the lethal effect. Rotifers prolonged their first reproductive time and shortened their reproductive period and longevity with the increasing of radiation dose, and the fecundity was significant inhibited by UV-B radiation. These responses can be taken as energy trade-off to retard their mortality. The population density of the rotifers increased at the lowest dose of radiation and then descended with the increasing of UVR dose, and this pattern was also corroborated by detecting the content of SOD and CAT, which suggested that hormesis also applies to R. rotatoria under UV-B radiation stress. The enzyme SOD has higher level of content and more sensitive to low UVR than CAT.

Background: UVB radiation is an increasing threat to aquatic organisms, and also a potential driving force for zooplankton population dynamics. The bdelloid rotifer, for its parthenogenesis and high resistance to stress, can be used as an excellent model in ecology and evolutionary biology. Given the strong tolerance of bdelloid rotifer to stressors, we hypothesized that it could hold the ability to tolerate significant UV radiation, and this capacity may be associated with the trade-off strategies among life historic components. With this study, to estimate the ecological effects and responses of antioxidant system against UV radiation, the acute lethal, life history strategies, population growth, and antioxidant enzyme activities were assessed in the bdelloid Rotaria rotatoria after exposure to UV-B radiation. Results: The persistence of tolerance (evaluating by LT50) in rotifer to stress was playing a more vital role than the radiation dose (LD50) in survival, with a significant negative correlation between the radiation intensity and LT50. The larger the culture volume, the weaker the lethal effect. Rotifers prolonged their first reproductive time (JP), and shortened their reproductive period (RP) and longevity with the increasing of radiation dose, and the fecundity was significant inhibited by UV-B radiation. These responses can be taken as energy trade-off to retard their mortality. The population density of rotifers increased at the lowest dose of radiation, and then descended with the increasing of UVR dose, and this pattern was also corroborated by detecting the content of SOD and CAT, which suggested that hormesis also applies to R. rotatoria under UV-B radiation stress. The enzyme SOD has higher level of content and more sensitive to low UVR than CAT.Conclusions: The lethal effects of UV-B radiation to organisms depends not only on the conditions they exposed to, like as intensity and time of exposure, but also combination of factors namely, the type and effectiveness of the strategy they employ to cope with the changed environment. The species specificity, ages and physiological status also could be the regulating factors under the stresses, also in this case there was the strategy of energy trade-off between reproduction and survival in rotifers.

The pitch deviation of gears caused by machining leads to corner contact in actual meshing process. In order to study the influence of the pitch deviation on motion characteristics of the spur gear pair, meshing state functions are constructed to reflect multi-state meshing including mesh-in at corner contact, mesh-out at corner contact, single and double pair drive-side teeth mesh, single and double pair back-side teeth contact and tooth disengagement. The nonlinear dynamics model of spur gear pair with pitch deviations under multi-state meshing is established. Variation laws of dynamic meshing forces and meshing states for the spur gear pair are analyzed. The influence of main parameters on nonlinear dynamics of the spur gear pair with pitch deviations is investigated. Results indicate that the pitch deviation results in complex periodic motion as a short-period error in spur gear pair. It mainly affects transmission stability of the spur gear pair by changing meshing states. This investigation provides a theoretical basis for the parameter design of the spur gear transmission system and the influence of pitch deviation in other gear transmission systems.

A novel water-soluble conjugated macrocyclic tetramaleimide (WCMT-1) with far red/near-infrared (FR/NIR) fluorescence emission has been rationally designed and successfully synthesized. WCMT-1 with the twisted donor (D) and acceptor (A) structures make it possess both aggregation-induce emission (AIE) and twist intramolecular charge transfer (TICT) characteristics. Due to the AIE effects, WCMT-1 exhibits a strong fluorescence in non-polar solvents (the quantum yield of WCMT-1 reaches to 33.7% in toluene and 32.5% in CCl4), but it is quenched in an aqueous solution caused by the TICT process. However, by the introduction of sodium lauryl sulfonate (SLS) into the WCMT-1 aqueous solution, the in situ generated WCMT-1&SLS supra-amphiphile resulted in remarkable recovery of FR/NIR fluorescence. Furthermore, combined with its large Stokes shift and good water solubility, the bioimaging experiments towards HeLa and HepG2 cells have also been conducted to give a good performance.

The aim of this study was to investigate the responses in filtration and grazing rates of five rotifer strains of the species Brachionus calyciflorus under different temperatures and MC-LR concentrations. The results showed that strain identity, MC-LR concentration, temperature, and the interactions of these factors significantly affected both response variables, with the exception of the interaction of strain and MC-LR on the grazing rates. At low MC-LR concentrations and for the control group, the filtration and grazing rates increased with increasing temperature. The filtering and grazing rates of B. calyciflorus exposed to higher MC-LR concentrations, however, showed no evident enhancement with increasing of temperature. At high temperatures, the filtration and grazing rates of all rotifer strains decreased significantly with increasing concentration of MC-LR, however B. calyciflorus exhibited a refractory stability in the presence of increased MC-LR levels at lower temperatures.

To study how the population genetic structure in zooplankton respond to environmental conditions, using comparative limnology, the genetic diversity and genetic differentiation of the B. calyciflorus complex collected from four inland lakes in Wuhu City, China were investigated based on the 16S rRNA gene and nuDNA ITS sequences. The results displayed a high genetic diversity, and the nucleotide diversity of the 16S rRNA gene was higher than that of the ITS sequence. The phylogenetic analyses grouped the four populations into two cryptic species (Bc-JT and Bc-FL) with strong support. The two cryptic species were found in lakes with different trophic levels, demonstrating significant ecological specialization. The origins of clone TW12 were not consistent in the phylogenetic trees between two genetic markers, which might be attributed to the effects of male-mediated gene flow on the phylogenetic relationships of rotifers. The nucleotide diversity of the cryptic species Bc-JT was higher than that of Bc-FL, indicating that eutrophication might decrease the genetic diversity of cryptic species. The total phosphorus concentration in water bodies might be the most important factor affecting the genetic diversity of species.

Phosphatase and tension homolog deleted on chromosome 10 (PTEN) was considered as a promising target in type 2 diabetes mellitus (T2DM) because of its negative effects on insulin resistance. Alteration in DNA methylation is thought to play a role in the pathogenesis of T2DM. The aim of the present study was to quantitatively evaluate the promoter methylation of PTEN in Uyghur patients with mild T2DM. We evaluated methylation levels in 21 CpG sites from −2515 bp to −2186 bp relative to the translation initiation site in 55 cases of T2DM and 50 cases of normal glucose tolerance (NGT) using the MassARRAY spectrometry. In addition, PTEN mRNA and protein levels were measured by quantitative reverse transcriptase polymerase chain reaction (qRT-PCR) and western blotting to determine whether DNA methylation alterations were responsible for PTEN expression. Compared with NGT groups, the PTEN mRNA expression was significantly higher in Uyghur patients with mild T2DM groups. We also showed that PTEN protein expression was upregulated in Uyghur patients with mild T2DM groups, but the level of protein kinase B (AKT) was downregulated. PTEN methylation in T2DM patients was significantly lower than that in NGT groups. In addition, 2 CpG units demonstrated a significant difference between the NGT and Uyghur patients with mild T2DM groups. Furthermore, there was a negative association between promoter methylation and PTEN expression. Together, these findings suggest that epigenetic inactivation of PTEN plays an important role in Uyghur patients with mild T2DM. The aberrant methylation of CpG sites within the PTEN promoter may serve as a potential candidate biomarker for T2DM in the Uyghur population.

Backlash plays a significant role in gear design and geared dynamics analysis. This study aims to establish a model of the time-varying backlash for a standard involute spur gear pair. The elastic deformations, thermal deformations and film thickness deformation at the meshing point are considered in this model. Asperity and fluid loads are included in film thickness. A time-varying backlash model with contact ratio is developed according to the force analysis at the meshing point. The contributions and effects of the various deformations on the backlash are analyzed. The effects of rotation speed, torque load and tooth surface temperature on the time-varying backlash are studied. Results show that the influence of various parameters on the backlash cannot be ignored. The time-varying backlash is less affected by elastic deformation and oil film thickness deformation, and is greatly affected by the thermal deformation. The time-varying backlash increases with the increase of torque load and the decreases of rotation speed and tooth surface temperature. Tooth surface temperature is validated experimentally due to its importance in the established model.

A face-gear drive system has been extensively used in important transmission devices with strict requirements for size and weight such as helicopter reducer and so on. Its dynamic characteristics directly affect the stability and reliability of the equipment. A piecewise torsional-bending-pendular nonlinear dynamics model of the face-gear drive system is established to study its nonlinear dynamics and dynamic characteristics. The multi-state engagements including drive-side teeth engaging, teeth disengagement, back-side teeth engaging, and alternate engaging between single-teeth pair and double-teeth pairs caused by the couple of the backlash and the contact ratio being greater than 1.0 is considered. The change of the dynamic engaging force and load distribution ratio for the system is analyzed by numerical results under three different states engagement. The effects of the load coefficient, meshing frequency and the comprehensive transmission error on the dynamic characteristics and nonlinear dynamics of the system are studied based on three different Poincare mappings defined by bifurcation diagrams, top Lyapunov exponent diagrams, phase portraits and variation curve of the dynamic engaging force. Results show that the complex phenomena such as teeth disengagement, drive-side and back-side impact occur with alternating meshing of the single and double pair teeth via the change of studied parameters. The research is helpful for the optimization of the face-gear drives.

Shell-and-tube heat exchangers with trefoil-hole baffles are new type heat transfer devices and widely used in nuclear power system due to their special advantages, with the fluid flowing longitudinally on the shell side. However, very few related academic literature are available. In order to obtain an understanding of the underlying mechanism of shell-side thermal augmentation, a CFD model including inlet and outlet nozzles is proposed in the present study. Based on the RNG k-ɛ model, numerical investigations on shell-side fluid flow and heat transfer are conducted by using commercial CFD software FLUENT14.0. The results show that the fluid is fully developed after the first trefoil-hole baffle. The heat transfer coefficient and pressure drop vary periodically along the axial direction. Fluid velocity increases gradually and the jet flow forms in the region near baffles. The secondary flow is also produced on the two sides of baffles when the fluid flows through trefoil-hole baffle. The jet flow and secondary flow can decrease the thickness of boundary layer and then enhance the heat transfer.

Context: Limited documentation exists on the effectiveness of education-based (EG) versus peer discussionbased (PDG) group interventions on perceived competence of adolescents suffering from medulloblastoma. Aims: This study was conducted to investigate which of these approaches offers the more beneficial outcomes to participants. Settings and Design: In a hospital in Zhenjiang, China, a total of 45 pediatric patients with standard risk or high risk medulloblastoma were randomly assigned to the EG or PDG interventions. Methods and Material: The Self-Perception Profile for Children (SPPC) and the Life Orientation Test—Revised (LOT-R) questionnaires were used to measure perceived competence and dispositional optimism or pessimism. Statistical analysis used: Adjustment was measured before the intervention, immediately after the intervention, at two weeks after, and six months after the intervention. Results: Participants in both groups showed improvement over time. The EG participants scored themselves higher on subscales including social acceptance, global self-worth and behavioral conduct at 2 weeks compared with those in the PDG (P

On the basis of the differential theory, an accurate and simplified model for predicting temperature distribution in the shell-and-tube heat exchanger is proposed. According to the baffle arrangement and tube passes, the heat exchanger is divided into a number of elements with tube side current in series and shell side current in parallel. Two examples of BEU and AES heat exchangers with single-phase fluid are analyzed to demonstrate the application and accuracy of the proposed model in temperature distribution prediction, compared with the Cell model and HTRI method. The results show that the proposed model reproduces the temperature distribution given by the HTRI solution on the tube side flow with 0.19% accuracy for the BEU heat exchanger and 0.35% for the AES heat exchanger. It indicates that the prediction of the temperature distribution by the new model agrees reasonably well with that by HTRI method.

Tooth surface contact deformation is part of the main causes for gear system vibration. The safety region of the single-stage spur system vibration is established based on the tooth surface contact deformation. Safe basin and its erosion are calculated numerically according to the safety region as the system control parameters are varied. The basin of attraction in the safe basin is computed by combining the simple cell-to-cell method. Vibration safety and global dynamics of the gear system are investigated. Some bifurcations and mechanisms of the erosion of safe basin are studied by using phase portraits, Poincaré maps, bifurcation diagrams under multi-initial values and top Lyapunov exponents (TLE). The sensitivity of system behavior and bifurcation to initial values are discussed as well. Hidden bifurcating points and attractors are revealed. To get a better understanding of the sensitivity of the system behavior to initial values, a bifurcation dendrogram under multi-initial values is designed. It is found that there is the erosion of safe basin existing in the examining area. Both vibration amplitude changing of coexisting attractors and appearing or disappearing of coexisting attractors are the main causes for the erosion of the safe basin. Bifurcation of the system behavior is selective to initial values. With varying frequency, backlash and comprehensive transmission error, the period-1 response gradually bifurcates under multi-initial conditions and evolves into other new periodic responses that coexist with the period-1 response. The new coexisting response has a key effect on the erosion of the safe basin. The study is helpful to the optimization design of the gear system and the control of the system behavior.

For years, prokaryotic hosts have been widely applied in bio-engineering. However, the confined in vivo enzyme clustering of heterologous metabolic pathways in these organisms often results in low local concentrations of enzymes and substrates, leading to a low productive efficacy. We developed a new method to accelerate a heterologous metabolic system by integrating a transcription activator-like effector (TALE)-based scaffold system into an Escherichia coli chassis. The binding abilities of the TALEs to the artificial DNA scaffold were measured through ChIP-PCR. The effect of the system was determined through a split GFP study and validated through the heterologous production of indole-3-acetic acid (IAA) by incorporating TALE-fused IAA biosynthetic enzymes in E. coli. To the best of our knowledge, we are the first to use the TALE system as a scaffold for the spatial organization of bacterial metabolism. This technique might be used to establish multi-enzymatic reaction programs in a prokaryotic chassis for various applications.

The complex dynamics characters of a third-order circuit system with nonlinear negative capacitance are studied. The dynamical equation and the state equation of the system are established. By the phase portraits, the motions of the system are studied under the definite parameters. And by bifurcation diagram, the route from periodic motion to chaos is studied under the presented system parameters. Two feedback methods are used to control the chaos of the circuit system. One is an adaptive method and the other is the feedback of states and parameter adjustment method. The phase plane portraits and bifurcation diagram of the controlled system are obtained. The advantages of the two controlled methods are that the collect of the control signals are simple and can put on any time and the chaotic system can be asymptotically stabilized to equilibriums with small control. The orbits of the system can be controlled by these two methods according to our target.

The bonds of T2 copper/50steel were studied by inertial radial friction welding techniques at different conditions. Ultrasonic C-scan testing was employed to evaluate the bonding situation. In order to verify the reliability of ultrasonic C-scan testing results, the optical microscope, SEM and shear test were used to analyse the microstructure and mechanical properties. It was found that ultrasonic C-scan testing was useful to evaluate the inertial radial friction welding joint situations by analyzing the ratio of good bonded area in the bond area of ultrasonic C-scan images. And the correctness of ultrasonic C-scan testing was testified by microstructure examination. Furthermore, it was concluded that enough metalline plastic deformation occurred, oxide film of joint was destroyed and constituent elements were mutually diffused sufficiently, when two stage pressure was employed and friction pressure 78 MPa, friction speed 3200r/min were used.

The joint property of aldary (T3 copper, B5 cupronickel and H96 brassiness) with 35CrMnSi by the use of inertial radial friction welding techniques is studied to meet the requirements of product operation . The microstructure of the welding joint, shear testing, vickers hardness and electron probe tests are carried out to verify the material weldability. The results show good performance of T3 copper, B5 cupronickel and H96 brassiness welded well with steel. The joints shear strength is more than 200Mpa, and no air hole flaw in weld seam that often occur in general fusion welding with dissimilar material. The welding properties can satisfy the requirements of the products. The results also indicate that under the same welding specification, the region of HAZ is related to thermal conductivity and melting point of copper-alloy, the microstructures of HAZ on B5＋35CrMnSi steel side is wider than others .

A series of new chiral dendritic BIPHEP ligands have been prepared and their applications in the Ru-catalyzed asymmetric hydrogenation of β-ketoesters were investigated. Ruthenium catalysts containing these dendrimer ligands were effective in the hydrogenation of β-ketoesters. It was found that the size of the dendritic wedges influenced the enantioselectivity significantly.

The microstructure of corroded HDDR-NdFeB magnetic powders in bonded magnet has been investigated by transmission electron microscopy. Following an exposure time of 300 h at 398 K in air, the HDDR-NdFeB magnetic powders are found covered with an altered layer about 300 nm thick on the surface. The layer is composed of α-Fe grains 5–10 nm in diameter and h -Nd 2 O 3 grains smaller than 5 nm. Under the altered layer, corrosion has proceeded along the Nd 2 (Fe,Co) 14 B grain boundaries to leave a wetting layer composed of a dense mixture of α-Fe and h -Nd 2 O 3 phase. The appearance of α-Fe grains in both of the altered layer wetting layer leads to the high magnetic flux loss of the corroded HDDR-NdFeB bonded magnet.

Nanocrystalline diamond films were grown in a hydrogen atmosphere by pulsed laser deposition (PLD). The transmission electron microscopy indicated the presence of non-oriented nanocrystalline diamond films, with crystallite diameters 10–20 nm, grown at an optimum hydrogen pressure of 4 Torr. A small amount of amorphous carbon was observed to have remained in the film. The typical deposition rate was 80 nm/min. The substrate temperature for the growth was 550 °C, which is lower by 150 °C than that of the conventional chemical vapor deposition. The deposited film had a smooth surface on the nanoscale.

We performed homo-growth of diamond thin films in an oxygen and hydrogen atmospheres on various oriented diamond substrates by pulsed laser deposition (PLD). The optimum ambient pressures were 50–70 mTorr for oxygen and 4 Torr for hydrogen, respectively. At 50 mTorr oxygen, diamond thin films, which consist of crystallites with diameters of 0.5–1 μm, were grown at a deposition rate of 18 nm/min. The diamond growth in the oxygen atmosphere was strongly influenced by the substrate orientation. However, at 4 Torr hydrogen, extremely smooth diamond films, which consist of non-oriented diamond crystallites with diameters of 20 nm at most, were grown at a deposition rate of 80 nm/min. The ambient hydrogen has an important role on the growth of nanocrystalline diamond. Based on these results, the diamond growth processes for respective atmospheres were discussed.

The microstructural modification for NdFeB magnetic powders (MQP-B) after Zn vapor sorption has been investigated by transmission electron microscopy (TEM). It is found that a coating layer about 100nm thick was formed on the surface of powder. Selected area electron diffraction (SAED) pattern and high resolution transmission electron microscopy (HRTEM) analyses show that the coating layer consists of condensed nano-scale crystallites of Fe 11 Zn 40 , NdZn 5 and Zn. After the temperature for Zn vapor sorption is raised to 648 K, a thin layer has been formed on boundaries of Nd 2 Fe 14 B grains locally in the rim region of the powders. The morphology of the grain-boundary thin-layers is very similar to that in HDDR-NdFeB magnet powder after Zn vapor sorption treatment. Since the latter has a good thermal stability of magnetic property, the Zn vapor sorption treatment is expected to improve also the thermal stability of MQP-B magnet.

Fetuin-A, which is known to inhibit insulin signaling and pathological calcification, has emerged as a diabetes risk biomarker. In the present study, the association between the fetuin-A levels with insulin resistance (IR) and carotid intima-media thickness (CIMT) was investigated in patients with new-onset type 2 diabetes mellitus (nT2DM). A total of 100 patients with nT2DM (nT2DM group) and 100 normal glucose tolerance (NGT group) controls were evaluated. The serum fetuin-A level was measured by a commercial solid-phase ELISA kit. The estimate of IR was calculated by homeostasis model assessment (HOMA-IR). CIMT was measured by B-mode ultrasound. The association between the serum fetuin-A levels and the metabolic parameters was also analyzed. The serum fetuin-A levels were increased significantly in the nT2DM group compared to the NGT group (368.5±15.6 mg/ml vs. 152.7±7.1 mg/ml, P

By reactive pulsed laser deposition under a hydrogen atmosphere, nanocrystalline diamond (NCD) films containing amorphous carbon were grown at a substrate temperature of 550°C. The deposition rate was 80 nm/min. The transmission electron microscopy (TEM) observation showed that nonoriented nanocrystalline diamond films, whose crystallite diameters were 10–20 nm, were grown at an optimum hydrogen pressure of 4 Torr. The deposited films had smooth surfaces on a nanoscale.

A self-exciting vibration model of a single-degree-of-freedom blooming mill, part of the main blooming drive system, is presented and its dynamical equation is established. According to the bifurcation, phase portrait and Poincare portrait, the nonlinear dynamical motions are studied in one parameter. The software Matlab/Simulink is used to create a block diagram of the circuit system. The result of the simulation verifies the motion of the circuit system and is consistent with a numerical simulation of the mechanical system. The software Multisim is used to simulate the mathematical description of the circuit, and a phase portrait analysis is performed. Because there are errors in the electronic elements, the result of the circuit simulation using Multisim is different from the numerical simulation of the mechanical system.

OBJECTIVE To set a quantified diagnostic standard for large intestinal cancer of spleen qi deficiency syndrome. METHODS The spleen qi deficiency syndrome was identified by experts on the basis of clinical epidemiological investigation of 311 patients suffering from large intestinal cancer. Corresponding points were assigned to the correlative factors (traditional Chinese medicine symptoms) on the basis of symptom differences between spleen qi deficiency syndrome and non-spleen-qi-deficiency syndrome. The best threshold was determined by receiver operating characteristic curve (ROC) according to syndrome differentiation from expert team, and the quantified diagnostic standard was established. The syndrome identification from the expert team which was regarded as golden standard was tested retrospectively. RESULTS All the traditional Chinese medicine symptoms possibly related to spleen qi deficiency syndrome were analyzed based on the opinions of experts, and 28 symptoms were confirmed as candidate correlative factors. The occurrence of 11 symptoms between spleen qi deficiency syndrome and non-spleen-qi-deficiency syndrome showed statistical differences by means of crosstabs analysis (P

This paper introduces a novel mobile ECG telemonitoring system. By means of CDMA1x (GPSOne) mobile telecommunication network, the system can perform "full time and space" monitoring of human ECG signal, and once the signal of the monitored subject departed from its normal ranges, the hospital ECG monitoring center can further localize his/her geographical position and give rescue in the first time. Another feature of the system is its high anti-interference capability. In order to reduce 50 Hz and RF interferences during mobile monitoring, which are usual much serious than conventional hospital monitoring, a new active recording technology was proposed and an active ECG recording electrode was designed. The system has passed the clinical test and used in China

Matthiessen’s rule has been applied to analyze the simultaneously measured electrical and thermal conductivities of polycrystalline platinum nanofilms. The results show that the greatly reduced conductivities are mainly attributed to the grain boundary scatterings. By taking into account the background scattering and the grain boundary scattering, Mathienssen’s rule slightly underestimates the thermal conductivity, but obviously overestimates the electrical conductivity. By introducing an additional parameter characterizing electron scattering on the grain boundary in Matthiessen’s rule, the agreement between the theoretical predictions and the observed results are greatly improved. Further studies show that when the mean grain size is much smaller than the corresponding mean free path, the electrons’ behavior inside the grains becomes affected by the grain boundaries and the underlying assumption of independent scattering processes for Mathiessen’s rule will become invalid.Copyright © 2007 by ASME