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Intermittent fasting (IF) is a dietary strategy that involves alternating periods of abstention from calorie consumption with periods of ad libitum food intake and has been shown to have beneficial effects in many ways. Recent studies have shown that IF attenuates neurodegeneration and improves cognitive decline, enhances functional recovery after stroke as well as attenuates the pathological and clinical features of epilepsy in animal models. Furthermore, IF induced several molecular and cellular adaptations in neurons that overall enhanced cellular stress resistance, synaptic plasticity, and neurogenesis. In this review, the beneficial effects of IF on central neurological disorders are discussed. The information summarised in this review can be used to help contextualise existing research and better guide the development of future IF interventions.

In this randomized, blinded study, we evaluated the effects of different programmed intermittent epidural bolus (PIEB) volumes for labor analgesia on the incidence of breakthrough pain and other analgesic outcomes.Nulliparous women with term cephalic singleton pregnancies who requested labor analgesia had epidural analgesia initiated with 10 mL 0.1% ropivacaine with sufentanil 0.3 μg/mL. The pump was programmed to deliver a 4, 6 or 8 mL bolus every 45 min (groups 4, 6 or 8, respectively). The primary outcome was the incidence of breakthrough pain, defined as inadequate analgesia after two patient-controlled epidural analgesia administrations in a 20-min period. Secondary outcomes included ropivacaine consumption, time of the first patient-controlled epidural analgesia request, duration of the second stage of labor, and incidence of motor block.Among 210 women randomly allocated the incidence of breakthrough pain was 34.9%, 19.7%, and 13.1%, for groups 4, 6 and 8, respectively (P=0.011). The incidence of breakthrough pain in group 8 was lower than in group 4 (P=0.006). The median (interquartile range) hourly ropivacaine consumption was 8.2 mg/h (7.1-11.3), 10.4 mg/h (9.2-13.0), and 12.0 mg/h (11.2-13.8) in groups 4, 6 and 8, respectively (P 0.001). Group 8 had a longer duration of effective analgesia and longer second stage of labor than group 4. There was no significant difference between groups in the incidence of motor block.The larger PIEB volumes were preferred for epidural labor analgesia compared with a smaller volume because of improved analgesia without clinically significant increases in adverse effects.

To explore the effect of sesamol on the cognition of APP/PS1 mice, 8-week-old APP/PS1 and wild-type male mice were divided into AD model group, AD + sesamol (50 mg kg−1 bw) group, and Control group. Sesamol was orally administered once a day for 5 months. Morris water maze was used to evaluate the learning and memory ability of mice. The number of synapses in the hippocampal neurons was detected by Golgi staining. Nissl staining was used to observe the changes of Nissl bodies in CA1 and CA3 regions of the hippocampus. Western blotting was used to detect the expression of Aβ, SIRT1, BDNF, and p-CREB/CREB in the hippocampus and cortex. Compared with the model group, sesamol decreased the latency period of APP/PS1 mice (P < 0.05) and increased the total number of neuronal dendritic spines in the hippocampal CA3 region, as well as increased the number of Nissl bodies (P < 0.05). Western blotting results showed that sesamol significantly reduced Aβ protein expression in the hippocampus and cortex, increased SIRT1 expression in the cortex, and increased BDNF expression in the hippocampus (P < 0.05). Sesamol improved the learning and memory abilities of APP/PS1 mice probably through increasing the density of neuronal dendritic spines and upregulating the levels of SIRT1 and BDNF.

To develop a split glomerular filtration rate (sGFR) prediction model based on unilateral renal volume parameters using three-dimensional (3D) computed tomography (CT) volumetry.Clinical data (age, sex, height, weight, serum creatinine level [sCr], and sGFR measured bysRPV (p0.001), sRCPV (p=0.012), age (p=0.015), serum creatinine level (p=0.004), and weight (p=0.006) were significantly associated with the measured sGFR and were included in the sGFR prediction formula, which was constructed as: 68.710 + 0.093 × sRPV-0.041 × sRCPV-0.228 × W-0.219 × A-14.432 × sCr (rThe proposed model based on sRPV and sRCPV parameters could be used for estimating split renal function of healthy renal donors and patients with hydronephrosis to some extent. Further studies are required to evaluate and rectify the model.

The study aimed to determine the effects of methionine hydroxy analog chelate zinc on the tibia quality, mineral deposit, apparent retention of nutrients, and liver metallothionein (MT) expression level of aged laying hens. A total of 960 layers (Hy-Line Grey, 57 wk old) were randomly assigned into 4 groups, and each group had 8 replicates of 30 hens. During the first 2 wk, groups were fed a basal diet without extra zinc (Zn: 35.08 mg/kg). During the ensuing 14 wk, 4 levels of Zn (inorganic Zn: 80 mg/kg; organic Zn: 20, 40, 80 mg/kg) were added to the diet. The results indicated that both the Zn source and level did influence tibia strength and calcium (Ca) and Zn concentrations of tibia (P < 0.05), whereas there were no differences in the copper (Cu) and phosphorus (P) concentrations of the tibia and the tibia length (P > 0.05). Moreover, dietary supplementation with 40 or 80 mg/kg of organic Zn showed higher Zn and Ca concentrations in the tibia and higher tibia strength. The Cu concentration in the liver showed no difference among the 4 treatments, whereas the Zn concentration in the liver increased with the increasing Zn level. The apparent retention of P, iron (Fe), and manganese (Mn) was not affected by the Zn level or source (P > 0.05). However, the organic Zn group increased the apparent retention of Cu, Zn, Ca, crude protein (CP), and energy, and the group supplemented with 40 or 80 mg/kg of organic Zn obtained significant effects (P < 0.05). Moreover, dietary supplementation with 40 or 80 mg/kg organic Zn increased the MT mRNA expression of the liver at week 72, whereas 20 mg/kg of organic Zn decreased it (P < 0.05). In conclusion, this study suggested that an optimum dietary (40 mg/kg) organic Zn level plays a key role in promoting the apparent retention of minerals and nutrients, trace element deposit, and MT mRNA expression.

This study aimed to evaluate the effects of vitamin C and vitamin E on antioxidant capacity and immune function in oxidative-stressed breeder roosters. One hundred twenty 45-week-old Lveyang black-boned breeder roosters were randomly assigned to 5 dietary treatments, including negative control group (NC), positive control group (PC), and 3 trial groups, which were fed the diets containing 300 mg/kg VC, 200 mg/kg VE, or 300 mg/kg VC and 200 mg/kg VE (VC+VE). At 47 wk of age, the positive control and trial groups were subcutaneously injected 3 times every other d with dexamethasone (DEX) 4 mg/kg of body weight, the negative control group was injected with saline. The experiment lasted for 35 d. The results showed that at 50 wk of age, average daily feed intake of birds challenged with DEX significantly increased (P0.05). During post-stress recovery period (52 wk of age), dietary supplemental VE or VC+VE notably increased body weight under oxidative stress (P0.01). Oxidative stress induced by DEX could significantly decrease superoxide dismutase (SOD), IgM, antibody titer of ND and mRNA expression of SOD or glutathion peroxidase activity (GSH-Px), increase serous malondialdehyde (MDA) (P0.05). Supplementation of VC or VE significantly decreased serous MDA, and increased SOD under oxidative stress (P0.05). Supplementation of VC or VE, or their combination significantly increased the relative expression of GSH-Px mRNA when compared to the oxidative-stressed control treatment (P0.05), whereas did not alleviate the relative expression of SOD mRNA (P0.05). Therefore, the results suggest that addition of 300 mg/kg VC, 200 mg/kg VE or their combination could improve antioxidant ability and immune performance in oxidative-stressed breeder roosters through up-regulating the expression of GSH-Px gene.

Endocan is a novel marker for inflammation but its significance in preeclampsia remains unknown. OBJECTIVE The aims of this study were to delineate the changes of maternal endocan in normal pregnancy and preeclampsia and to explore its possible role in the pathogenesis of preeclampsia. MATERIALS AND METHODS Blood samples were taken from 42 non-pregnant women, from 43 normal pregnant women at third trimester, and from 41 preeclamptic women. Serum endocan levels were determined with enzyme-linked immunosorbent assay (ELISA) and compared among the groups. RESULTS There were no significant differences in serum endocan among non-pregnant women, normal pregnant women, and women with preeclampsia (X²= 2.207, p = 0.137) and there was no significant difference in serum endocan between women with mild and severe preeclampsia (Z= 0.368, p = 0. 713). The authors concluded that serum endocan did not change in pregnancy and preeclampsia, indicating endocan may not be involved in the pathogenesis of preeclampsia.

The inverse velocity method is widely used for slope failure time prediction. In practice, the presence of factors like measurement error, environmental noise, and modeling assumptions may make the predicted failure time different from the actual failure time. While the traditional inverse velocity method can provide useful information about the probable failure time, it does not furnish an estimate about the reliability of the prediction. In this paper, the uncertainties in slope failure time forecast are divided into two categories, i.e., observational uncertainty and model uncertainty. A method is suggested to assess the effect of observational uncertainty on slope failure time prediction through site-specific data based on the maximum likelihood principle. The model uncertainty associated with the inverse velocity method is calibrated based on a database containing 50 landslides with known failure time. A procedure is suggested to predict the probability density function of the slope failure time considering both uncertainties. Two illustrative examples are provided to show that the outcome from the probabilistic method suggested in this paper can be more informative for rational decision making.

A number of typical mobile robots can be described by the chained form or more general nonholonomic systems. Due to Brockett’s theorem, it is well known that nonholonomic systems with restricted mobility cannot be stabilized to a desired configuration via differentiable, or even continuous, pure-state feedback. It is noted that one commonly used approach for control system design of nonholonomic systems is to convert, with appropriate state and input transformations, the original systems into some canonical forms for which controller design can be carried out more easily. The stabilization problem is considered for general nonholonomic mobile robots at the actuator level, taking into account the uncertainties in dynamics and the actuators. The existence and construction of the transformation for these systems have been established in the literature. The chapter investigates stabilization of uncertain nonholonomic mobile robotic systems with unknown constant inertia parameters and actuator dynamics.

Effects of preslaughter immunological stress induced by lipopolysaccharide (LPS) on antioxidant performance and meat quality of broilers were investigated. Twenty-four broiler chickens (39 days old) with near-mean body weight (BW) were randomly divided into three following treatments: sham injection of saline (control), daily subcutaneous (s.c.) injection of LPS (3 mg/kg or 6 mg/kg of BW, respectively.) for three days. The results showed that average daily feed intake and daily gain of chickens were significantly decreased in the LPS treatment (P 0.05). The LPS treatment significantly decreased the pH at 24 h postmortem in breast muscle (P < 0.05) and significantly increased the water-holding capacity (WHC) of breast muscle (P < 0.01). It was the same as the change of yellowness (b*) at day 3 postmortem and lightness (L*) at day 6 postmortem in breast muscle (P < 0.05), but ha...

This study was undertaken to assess dietary crude protein (CP) concentration for optimum growth performance and carcass characteristics of Lueyang black-boned chicken. In total, six hundred 42-day-old Lueyang black-boned chicks were randomly assigned to five treatments, each with six replicate pens with ten males and ten females. The birds fed experimental diets with different levels of protein concentration of 120, 140, 160, 180 and 200 g kg-1 from seven to twelve weeks of age respectively. On day of 84, weight gain, feed intake, and feed:gain ratio were measured, and two chickens (one male and one female) close to the average weight of all birds in each treatment were selected from each pen and sacrificed to evaluate carcass traits and selected serum biochemical indexes. Dietary CP concentration did not have any significant influence on feed intake (p>0.05). The birds fed the diet with 180 or 160 g kg-1 CP concentration exhibited greater (p

Thermal receive‐storage cavity is made of superalloy. It work in harsh conditions, for example, high temperature, thermal shock and corrosion. What’s more, reflector structure has important influence on radiation utilization. Consequently, for cylindrical cavity receiver, the effects of conical reflector and (with different taper angles which marked with 2φ) hemispheric reflectors on radiation heat flux and temperature uniformity on the receiver cavity inside surface were studied. Solar radiation utilization of the cavity with hemisphere reflector is lower than that of cone reflector with any taper angles; when φ

Using the dielectric continuum approach, we study the optical vibration modes in a polar spherical multilayer nanostructure hosted in a non-polar material. The dispersion relation and the corresponding electron–phonon interaction Hamiltonians for interface optical (IO) or surface optical (SO) phonons are derived. As a typical case, the numerical results for the CdSe/ZnS/CdSe spherical multilayer nanostructure are given. The frequency and electric potential characteristics of 5 branches of IO/SO phonon modes are analyzed. The results show that the electron–phonon coupling related to the IO modes with higher frequencies and the SO modes are more significant.

V-doped and undoped SrTiO3 (V:STO and STO) thin films on Pt/Ti/SiO2/Si substrates were synthesized using a sol–gel method to form metal–insulator–metal (MIM) structures. Coexistence of the bipolar and unipolar resistive switching (BRS and URS) modes in Pt/STO/Pt and Pt/V:STO/Pt structures was observed as a irreversible transition from BRS to URS on adjustment of the compliance current (I comp). Both states were stable and reproducible over 60 cycles, and the maximum operating voltage of the Pt/STO/Pt was reduced from 10 V to 2 V by doping with V. Linear fitting of current–voltage curves suggests that space-charge-limited leakage was the limiting leakage mechanism for these two devices. Based on these results, a switching mechanism based on filament theory is proposed to explain both resistive switching modes.

Antibacterial polyethersulfone/silver nanoparticle ultrafiltration membrane was prepared. The result revealed that the membrane exhibited the excellent property by showing bovine serum albumin (BSA) rejection of 73.6 % with no significant change in water flux when the n-Ag content was 0.5 wt% and the blending temperature was 80℃. The membranes surface contact angle was also reported to increase significantly.

Design of microstructured reactors with thermal control function is investigated through numerical simulation. It consists of one middle channel for handling chemicals and two other channels attached to its top and bottom for cooling purpose. Three designs are examined. Reactor A uses simple straight channels. In reactor B, chaotic flow is applied to the middle channel, and in reactor C chaotic flow is applied to all the three channels. Results show that in comparison with the straight channel, the Nusselt number in current design is greatly improved through chaotic flow. Rapid mixing is also achieved. Potential application of the design for continuous exothermic process is analyzed. For reactor A, it is not workable as the temperature of the chemical solution continuously increases over the channel. In comparison, for both reactors B and C the temperature can be well controlled within the required range. As the coolant flow in reactor C is also chaotic, it provides a higher heat removal capacity.

Indium oxide flowerlike films were prepared on glass substrate by a simple chemical vapor deposition (CVD) coating technique. The results showed the products on the glass surface are flowerlike body centered cubic structure of In2O3 films. The flowerlike microstructures are distributed uniformly and have less overlapping, the diameters of them are about 3 µm. The deposition mechanism and the morphologies control procedure of the In2O3 were studied. As the reaction time increases, the morphologies of the microstructures were changed from cocoon-like particles to hybrid thin films, and flowerlike microstructures at last. This novel CVD method might provide a simple route for synthesizing other metal oxide or compound films.

SUMMARY This experiment was conducted to evaluate the effects of distillers dried grains with solubles (DDGS) on the meat quality and antioxidant status and capacity of broiler chickens. One-dayold male broiler chickens (720) were assigned to 6 treatments, with 4 replicates per treatment. Birds were fed diets formulated to contain 0, 5, 10, 15, 20, and 25% corn-based DDGS, respectively, for a period of 6 wk. The addition of DDGS influenced the general meat quality by affecting the b* (yellowness) values, cooking loss, and shear force (P 0.05), but feeding DDGS significantly increased the ratio of polyunsaturated to saturated fatty acids (P 0.05) by dietary DDGS concentrations; however, liver malondialdehyde production was influenced significantly (P < 0.01) by dietary DDGS levels. Overall, including DDGS at concentrations up to 15% in the broiler diet is feasible and can result in ideal meat quality.

Casting duplex stainless steels (CDSSs) used for pressurized water reactor (PWR) pipes are susceptible to thermal aging brittleness during long-term service at its working temperature from 288 °C to 327 °C. In order to investigate its thermal aging behavior, Z3CN20-09M CDSSs have been thermally aged at 400 °C up to 15,000 h. The micro-hardness of austenite and ferrite phases, conventional tensile properties, impact properties and SPT properties at different aging duration have been measured. The results show that the micro-hardness in ferrite gradually increases with increase of long thermal aging time, while the effect of the long aging time on the micro-hardness in austenite is negligible. The tensile strength and yield strength progressively and slightly increase with the long aging time, respectively. The impact property test confirms that there is the same change tendency as the percentage of elongation which decreases with the long aging time. The changes of SPT ultimate strength, SPT yield strength and SPT specific fracture energy by aging individually show that there is an almost same tendency as the tensile strength, the yield strength and the percentage of elongation with the thermal aging time. All above the mechanical properties changes of Z3CN20-09M CDSSs are associated with the changes of the dislocation configurations in austenite, the precipitation of G-phase on the dislocation line and in ferrite phase, the spinodal decomposition and the coarsening of the spinodally decomposed structure in ferrite after different thermal aging time.

Polycrystalline ZnO films are deposited on Pt/Ti/SiO"2/Si substrate by chemical solution deposition (CSD) method. Metal/ZnO/Pt sandwich structures were constructed by depositing different top electrodes. Unipolar switching and bipolar switching characteristics were investigated in Pt/ZnO/Pt and Ag/ZnO/Pt structures, respectively. Analysis of linear fitting current-voltage curves suggests that the space charge limited leakage was observed as the limiting leakage mechanism of these two devices. And, the electrochemical migration of oxygen vacancies and metal ions resulted from the selecting electrodes was applied to explain the resistive switching behaviors.

The aim was to investigate the factors that affect graft function at 2 years after transplantation in living related-donor kidney transplantation.We retrospectively reviewed the clinical data of 144 patients who underwent living related-donor kidney transplantation in our hospital from December 2005 to December 2008. Recipients were divided into 2 groups according to glomerular filtration rate (GFR) at 2 years after transplantation: ≤60 mL/min/1.73 m2 (n=51) and60 mL/min/1.73 m2 (n=93). Variables which affected graft function were compared between the groups. The significant factors were analyzed using logistic regression.Univariate analysis showed significant differences for donor age, donor GFR, recipient weight, recipient body mass index, donor-to-recipient body weight ratio, and acute rejection episodes (P.05). Logistic regression analysis revealed the independent factors affecting renal function at 2 years after transplantation to be donor GFR (β=0.032; odds ratio [OR] 1.032; P=.004) and recipient body weight (β=-0.069; OR 0.934; P=.001). Receiver operating characteristic (ROC) curve analysis showed cutoff values of donor GFR and recipient body weight to be111.25 mL/min/1.73 m2, and ≤67 kg, respectively. Areas under the ROC curve of donor GFR and recipient body weight were 0.612 and 0.665, respectively. Sensitivity and specificity of donor GFR were 43.0% and 78.4%, respectively. Sensitivity and specificity of recipient body weight were 82.8% and 45.1%, respectively.Donor GFR and recipient body weight were the independent factors effecting renal function at 2 years after transplantation.

Rare earth element La-doped ZnO polycrystalline films are prepared on Pt/Ti/SiO 2 /Si substrate and p -Si substrate by chemical solution deposition (CSD) method. High R OFF / R ON ratios, low operation voltages within 150 switching cycles of test and long retention measurement are obtained, which indicate that the two different structure devices exhibit reversible, controllable and remarkable reliability unipolar resistive switching (RS) behaviors. The RS mechanism is related to the different substrate of the samples. The filament theory and the interface effect are suggested to be responsible for the RS phenomenon for the Pt/Ti/SiO 2 /Si substrate and p -Si substrate, respectively.

The use of approximate Poincare maps for prediction of chaotic mixing in spatial-periodic channel is investigated in this article. The maps are constructed based on the corresponding distribution of discrete tracers on two successive Poincare sections. Three methods are analysed including the triangular weighted interpolation, Shepard's method and weighted-least-square polynomial fitting (WLS-PF). Their application to a three-dimensional (3D) chaotic micromixer is demonstrated. Relevant results show that all the schemes can provide reliable predictions of the mixing quality within a limited number of mixer units. Among the three, the WLS-PF is less influenced by the grid-sizes. The mapping approach provides an alternative way to examine the performance of the spatial-periodic chaotic micromixer. It will greatly reduce the enormous efforts involved in 3D computational fluid dynamics (CFD) analysis.

The energy of a biexciton in a GaAs/AlxGa1−xAs quantum well structure with finite barriers is investigated by using the geometrical model of two-dimensional biexcitons proposed by Singh et al. [J. Singh, D. Birkedal, V.G. Layssenko, J.M. Hvam, Phys. Rev. B 53 (1996) 15909; I.-K. Oh, J. Singh, Phys. Rev. B 60 (1999) 2528]. A fractional-dimensional approach is used to obtain the binding energy of the biexciton in both square quantum wells and parabolic quantum wells. Theoretical results show that the binding energy of a biexciton in a finite quantum well exhibits a maximum with increasing well width. The ratio of the binding energy of a biexciton to that of an exciton in a quantum well structure is found to be sensitive to the electron-to-hole mass ratio and larger than that in the three-dimensional system. The results agree fairly well with previous experimental results. The results of our approach are also compared with those of earlier theories.

Electron–phonon effects on Stark shifts of excitons in parabolic quantum wells are studied theoretically by using a fractional dimension method in combination with a Lee–Low–Pines-like transformation and a perturbation theory. The numerical results for the exciton binding energies and electron–phonon contributions to the binding energies as functions of the well width and the electric field in the Al 0.3 Ga 0.7 As parabolic quantum well structure are obtained. It is shown that both exciton binding energy and electron–phonon contributions have a maximum with increasing the well width. The binding energy and electron–phonon contribution decrease significantly with increasing the electric-field strength, in special in the wide-well case.

In this paper, an adaptive neural network controller is presented for smart materials robots using Singular Perturbation techniques by modeling the flexible modes and their derivatives as the fast variables and link variables as slow variables. The neural network (NN) controller is to control the slow dynamics in order to eliminate the need for the tedious dynamic modeling and the error prone process in obtaining the regressor matrix. In addition, inverse dynamic model evaluation is not required and the time-consuming training process is avoided except for initializing the NNs based on the approximate function values at the initial posture at time t = 0. The smart materials bonded along the links are used to active suppress the residue vibration. Simulation results have shown that the controller can control the system successfully and effectively.

In this paper, we investigate robust adaptive controls of multiple mobile manipulators carrying a common object in a cooperative manner with unknown inertia parameters and disturbances. First, a concise dynamics consisting of the dynamics of mobile manipulators and the geometrical constraints between the end-effectors and the object is developed for coordinated multiple mobile manipulators. Subsequently, we design robust adaptive controls where parametric uncertainties are compensated by adaptive update techniques and the disturbances are suppressed. The controls ensure that the output tracking errors of the system converge to zero whereas the internal force tracking error remains bounded and can be made arbitrarily small. Throughout this paper, feedback control design and stability analysis are performed via explicit Lyapunov techniques. Simulation studies on the control of coordinated two wheels driven mobile manipulators show the effectiveness of the proposed scheme.

The graphite surfaces were irradiated by Ar+ ions with and without a simultaneous Co supply at room temperature. The sputtered surface without Co supply was characterized by densely distributed conical protrusions with aligned carbon nanofibers (CNFs) on the tops, whereas Ar+-bombarded surfaces with a simultaneous Co supply were covered with asparagus-like (micrometer order in base diameter) or nanofibrous (10–50 nm in diameter) structures depending on the supply rate of Co atoms. No CNF-tipped cones were observed to form. For the nanofibers containing carbon and cobalt, the hysteresis behavior observed in the magnetization property by applying magnetic fields in directions perpendicular and parallel (in-plain) to the substrate was almost identical, whereas a continuous 1 µm thick-Co film showed the strong in-plane anisotropy. Other materials could be readily incorporated into CNFs by choosing the suitable metal sources. Thus, the ion-irradiation method is expected to open up a new approach to fabricate ferromagnetic 1-D nanomaterials at room temperature.

Graphite surfaces were bombarded with Ne+, Ar+ and Xe+ ions at 450 eV–1 keV to induce the carbon nanofiber (CNF) growth at room temperature, and the dependence of size and numerical density of ion-induced CNFs on the ion species and ion energy was investigated in detail. The ion-sputtered surfaces were covered with densely distributed conical protrusions and aligned CNFs grew on the tips, except for the low-energy Xe+-sputtered surfaces. Longer CNFs grew by lighter-mass-ion irradiation, and finer CNFs formed by heavier-mass-ion bombardment. In addition, the higher the ion energy, the longer the length of the ion-induced CNFs. Because the size and numerical density were controllable by the ion-irradiation parameters, ion-induced CNFs were believed to be quite promising for myriad of applications such as high-resolution scanning probe microscope cantilevers, bio-cell manipulators and field emission source operating at low voltage.

The adsorption structure and the spin-resolved electronic properties of a pentacene molecule adsorbed on the Fe(1 0 0) surface are investigated by means of ab initio calculations on the basis of the density functional theory. The pentacene molecule was found to adsorb with its molecular plane lying flat on the surface at low coverage and with it tilting from the surface at high coverage. The spin polarization is negative at the donated molecular orbitals and positive at the backdonated (induced 4 b 1u ( π ∗ ) ) orbital close to the Fermi level, which is indicated by the computation of the spin density distributions and plane-averaged density of states at the vacuum side. This opposite spin polarization is quite consistent with a previous experimental result of spin asymmetry in the spin-polarized metastable-atom deexcitation spectra.

The spin polarization of benzene molecules on an Fe(1 0 0) surface is investigated by density functional calculations and spin-polarized metastable-atom deexcitation spectroscopy (SPMDS). The spin asymmetry in the molecular orbitals, observed by SPMDS, does not decrease to zero at a multilayer coverage of benzene. Spin-resolved electronic states are calculated for several adsorption geometries. In double-layer adsorption, only the π orbitals are spin-polarized, while σ orbitals have no spin polarization. In tilted and edge-on adsorption, the spin polarization is negative at the molecular peaks and positive in the valley between two molecular peaks, which is in good agreement with the spin asymmetry at 8 L.

In this paper, robust force/motion control strategies are presented for mobile manipulators under both holonomic and non-holonomic constraints in the presence of uncertainties and disturbances. The proposed control strategies guarantee that the system motion converges to the desired manifold with prescribed performance and constraint force control is developed using the passivity of hybrid joints rather than force feedback control. Experiment results validate that not only the states of the system asymptotically converge to the desired trajectory, but also the constraint force asymptotically converges to the desired force.

The epoxy-based anisotropic conductive film (ACF) joints have the potential of being exposed to a hygrothermal environment and susceptible to moisture sorption. The long-term hygrothermal aging will induce the irreversible damages of epoxy resins system due to susceptibility of the polymer to hydrolysis, oxidation, etc. In this study, the hygrothermal environment test was used as an accelerator for the degradation of ACF joints in Chip-on-Glass (COG) assemblies. The effects of aging on the adhesion strengths were measured by shear mode tests and the changes of molecular conformation were analyzed by Fourier Transform Infrared Spectroscopy (FTIR). Results show that the ACF adhesion strengths decrease with aging and there are some chemical modifications to the aged ACF joints.

In this study, three-dimensional temperature fields induced by AC and DC through a spiral electric resistor in a line-heater are numerically investigated. Electric heaters have been widely found, for example, in houses as dryers, stoves, and water heaters, and in industrial and research institutions as elements of equipments. The line-heater in the present model is realistically considered to have multiple regions composed of a spiral electric resistor, electrically insulated region, covering outer layer, and two terminal pins with distinct thermal and electrical properties. Solving unsteady three-dimensional heat conduction equations in distinct regions, the surface temperatures predicted as a function of time in this model are confirmed by the measured data. The calculated results quantitatively show that high surface temperatures of the heater can be reached by increasing dimensionless joule heat parameter, radius of the spiral electric resistor or pins, thermal diffusivity of the insulation region, and decreasing Biot number and radius of insulation region. The effects of the pins on surface temperature are also studied. Aside from showing that DC produces higher temperature than AC, the results indicate that the effects of current frequency on temperature fields are insignificant. The findings can be generalized to a curved heater, because any local location can be considered as a small line-segment. The present work provides general and quantitative data valuable for designing an efficient heater/furnace.

In this paper, we have constructed and analyzed the field emission behavior of a single vertically aligned free standing carbon nanotube (CNT) with a gate electrode in order to verify the feasibility of using a single CNT as the low-voltage field emission electron source. The single vertically aligned CNT with gate electrode was fabricated by combining optical lithography, electron beam lithography (EBL) and inductively coupled plasma chemical vapor deposition (ICP-CVD) processes. A self-aligned process with a single mask was utilized to define the gated structure and the nano-size catalyst for CNT growth. A single vertically aligned CNT was then grown within the gate hole by ICP-CVD. The length-to-diameter ratio of CNT could be varied by adjusting the e-beam exposure time, and the CNT height was controlled to equal to the gate-to-cathode spacing (800) nm in one gated device and less than the spacing (530 nm) in another device. The field emission characteristics of the integrated gate electrode devices were then measured under a scanning electron microscopy (SEM) with a three-axis nano-positioning device. The turn-on field of the gated devices with 800 and 530 nm height CNT were 2.77 and 3.57 V/μm, respectively, with applying − 10 V gate voltage, and 0 V anode voltage.

Benzoic acid (C 6 H 5 COOH, BA) has been studied by high pressure Raman and fluorescence spectroscopy up to about 13.40 GPa using a diamond anvil cell at room temperature. The changes of lattice modes are interpreted as the crystal structure transformation. Three possible phase transitions, with the pressure increasing up to about 0.55, 3.67 and 11.10 GPa, are, respectively, elucidated as crystalline-to-crystalline, crystalline-to-amorphous transitions. A new material formed when the pressure is up to above 11.10 GPa remains stable after the pressure is released.

An adaptive neural-fuzzy controller is presented in this paper for mechanical systems with nonholonomic constraints in the presence of uncertainties about plant parameters. The controller is designed based on a reduced model. The neural-fuzzy (NF) controller is constructed in order to eliminate the need for dynamic modeling and error prone process in obtaining the regressor matrix. The proposed controller guarantees that the system motion asymptotically converges to the desired manifold. Numerical simulation are conducted to verify the effectiveness of the proposed method.

In this paper, robust control strategies are presented systematically for both holonomic mechanical systems and a large class of nonholonomic mechanical systems in the presence of uncertainties and disturbances. First, robust control strategies are presented for both kinds of systems using the bounds of system parameters, respectively. Then, adaptive robust control strategies are presented by tuning the parameter estimates online. Proportional plus integral feedback control is used for force control for the benefit of real-time implementation. The proposed control strategies guarantee that the system motion converges to the desired manifold with prescribed performance while the constraint force remains bounded.

In this paper, adaptive state feedback and output feedback control strategies are presented for a class of nonholonomic systems in chained form with drift nonlinearity and parametric uncertainties. Both control laws are developed using state scaling and backstepping techniques. In particular, novel adaptive switching is proposed to overcome the uncontrollablity problem associated with x"0(t"0)=0. Observer-based output feedback design is developed when only partial system states are measurable, and a filtered observer rather than the traditional linear observer is used to handle the technical problem due to the presence of unavailable states in the regressor matrix. The proposed control strategies can steer the system globally converge to the origin, while the estimated parameters maintain bounded.

Fracture toughness is regarded as an important fracture criterion for materials when fracture mechanics is applied to assess the reliability of microelectronics packages. Fracture toughness of a filled epoxy is related to material, process and test conditions. Plane-strain based characterization methodologies have been successfully developed to characterize fracture toughness of bulk filled epoxy materials. However, those methodologies may not be applicable for filled epoxy films, due to the differences in stress-state and degree of curing in the films when compared to bulk specimens. In this paper, strain energy release rate was proposed to be a representative for the description of the fracture behavior of filled epoxy materials. Based on linear elastic fracture mechanics and microdigital image speckle correlation technique, a plane-stress based fracture toughness characterization methodology, including theoretical model, measurement facility, experimental approach and analysis method, was developed. With the methodology, the fracture toughness of a silica filled epoxy film, which is widely used in microelectronics packages as an underfill material, was characterized over a wide temperature range (−40 to 200 °C). The fracture toughness of the film was found to have a nonlinear relationship with testing temperature, i.e., the temperature dependence in the low temperature range is much lower than that in the intermediate temperature range, but is higher than that in the high temperature range.

A computer model for the poly-Si thin film-related solar cells is established, with which the solar cells with the structure of single junction poly-Si cell, a-Si/poly-Si tandem cell and a-Si/poly-Si/poly-Si triple cell are simulated. The results indicate that the practical structure for poly-Si-related solar cell is a-Si/poly-Si/poly-Si triple cell with the best matched thickness of 0.23/0.95/3 μm and with optical confinement structure, which has the highest simulated efficiency of 22.74%.