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Inner suspension platform of a spherical robot undergoes dynamic oscillation process when the robot is rolling ahead, which significantly reduces stability and precision of the motion. To suppress these vibrations, this study considers an adaptive sliding mode control method for a spherical robot based on application of magnetorheological (MR) fluid actuator. After analyzing the mechanical structure of the spherical robot, a dynamic model describing its rolling motion is derived. Considering the uncertainty of the disturbances introduced by modeling error and outside perturbation, an adaptive scheme is proposed to estimate the dynamic disturbances. Sliding mode technology is applied to construct system controller characterized by robustness and parameter insensibility. Simulations are performed in order to verify the effectiveness of the proposed control methods. [ABSTRACT FROM AUTHOR]

An experiment was conducted using a total of 540 one-day-old Yangzhou geese to study the effect of rearing system on growth performance, carcass traits, and meat quality of male and female Yangzhou geese. The birds were divided into homogeneous groups according to initial BW and sex. The male and female geese were raised in separate pens under 5 different treatments, with 3 replicate pens of 18 male or 18 female geese per pen for each treatment. This experiment included 2 stages, with geese at 1 to 28 d of age (the first stage) and 29 to 70 d of age (the second stage). The 5 different treatments were 1) system A (geese raised on a wire floor), 2) system B (geese raised on the floor), 3) system C (geese raised on the floor and transferred to to a wire floor), 4) system D (geese raised on a wire floor and transferred to the floor), and 5) system E (gees raised on the floor and transferred to a free range). Results showed that feed conversion rate, BW, and BW gain were significantly affected by rearing system and sex (P < 0.05). For carcass yield, results suggested that eviscerated carcass yield and heart yield were affected by rearing system (P < 0.05) but not by sex (P > 0.05). Differences between sexes, but not rearing systems, were observed for only breast yield, thigh yield, and liver yield (P < 0.05). Rearing system and sex had a remarkable effect (P < 0.05) on subcutaneous fat thickness, abdominal fat yield, and gizzard yield. The nutrient composition (water, protein, and fat), water-holding capacity, shear force, and pH of the pectoralis major muscle were not affected (P > 0.05) by the rearing system, and only water, protein, and pH of the meat were affected by sex (P < 0.05). This study indicates that rearing system A, in which Yangzhou geese were raised on a wire floor, improved growth performance but had little effect on meat quality, implying that the use of rearing system A, using a wire floor, might be feasible and effective for Yangzhou geese. [ABSTRACT FROM AUTHOR]

In this article, effect of temperature on elastic properties of single-walled carbon nanotubes is investigated by means of a molecular structural mechanics model in which the primary bonds between two nearest-neighboring atoms are treated as a two-node dimensional Euler--Bernoulli beam. By considering the effect of environmental temperature on force constant values of bond stretching, bond angle bending, and torsional resistance, the corresponding basic parameters of these two-node dimensional Euler--Bernoulli beam elements are obtained under different environmental temperatures, respectively. Nano-scale finite element simulations of the elastic properties of single-walled carbon nanotubes under different environmental temperatures reveal that the elastic modulus of single-walled carbon nanotubes decreases significantly with the increase of temperature. It is noted that the Young's modulus of armchair nanotubes is more sensitive to environmental temperature due to the tube chirality. Finally, the relationship between elastic modulus of zigzag and armchair carbon nanotubes and environmental temperature is given by a simple formula. [ABSTRACT FROM AUTHOR]

This study was carried out to evaluate the transport capacity equations of the Yalin equation and the WEPP model for steep slopes, and to recommend the best-fitting exponent value of shear stress in the WEPP transport capacity equation. The transport capacity was measured in a 5 m long, 0.4 m wide hydraulic flume, and the diameter of test sediment varied from 20 to 2000 µm with a meadian diameter of 280 µm. Flow discharge ranged from 0.625 x 10-3 to 5 x 10-3 m² s-1, and slope gradient ranged from 8.8% to 46.6%. An averaged dimensionless critical shear stress of 0.052 was used for Tc calculation in the Yalin equation. The relationship between transport coefficient Kt and shear stress was graphically determined for the transport capacity equation of the WEPP model. The transport capacities predicted by the Yalin equation and the WEPP model were compared with the measured Tc to qualify their suitability on steep slopes. The results showed that the Yalin equation overestimated the measured Tc by 109%. The error increased as a power function of shear stress (r² = 0.97). The transport capacity of the WEPP model underestimated the measured Tc by 65%. The absolute error increased as a linear function of shear stress (r² = 0.91). Paired t-tests showed that the transport capacities calculated using the Yalin and WEPP equations were different significantly from measured Tc at the 0.05 level. Sediment transport coefficient Kt, calculated with the WEPP equation using the measured Tc of this study, varied with shear stress. However, Kt converged to a steady value of 0.053 when the best-fitting exponent of 2 for shear stress was used (r² = 0.98). Thus, Kt τ² is considered when estimating Tc for steep slopes. More studies are needed to further evaluate the WEPP Tc equation as well as this new equation using various soils on steep slopes. [ABSTRACT FROM AUTHOR]

The phenotype and haplotype frequencies of human leukocyte antigens (HLA)-DR and -DQ in 32 Chinese patients with the mucocutaneous (MC) type of Behçets disease (BD) were calculated and compared with those in 310 healthy control Chinese and with those in 80 Chinese patients with recurrent aphthous stomatitis (RAS). We found that the phenotype frequency of HLA-DRw8 [corrected P (Pc)<0.005] and the haplotype frequencies of HLA-DRw8/DQw1 (Pc<0.005), -DRw8/DQw5(w1) (Pc<0.0005), -DRw12(5)/DQw1 (Pc<0.005), -DRw12(5)/DQw6(w1) (Pc 0.0005), and -DRw52/DQw1 (Pc<0.005) in patients with the MC type of BD were significantly greater than those in healthy control subjects. This finding suggests that individual Chinese with HLADRwB antigen and HLA-DRw8/DQw1, -DRw8/DQw5(w1), -DRw12(5)/DQw1, -DRw12(5)/DQw6(w1) and -DRw52/DQw1 haplotypes are more likely to have the MC type of BD. Furthermore, the relative risks (RRs) of HLA-DRw8/DQw1 (5.6), -DRw8/ DQw5 (w1) (10.0). and -DRw12(5)/DQw6(w1) (14.4) haplotypes in patients with the MC type of BD were equal to or higher than the RR of HLA-DRw8 phenotype (5.6), suggesting that some of the HLA-DR/DQ haplotypes may play more important roles than the individual HLA-DR and DQ phenotypes for the development of the MC type of BD. The phenotype frequencies of HLA-DR5 (Pc<0.01), -DRw8 (Pc<0.005) and -DQw1 (Pc<0.05) as well as the haplotype frequencies of HLA-DR5/DQw1 (Pc<0.005) and DRw8/DQw1 (Pc<0.00005) in patients with the MC type of BD were significantly higher than those in patients with RAS. Moresover, the RRs of HLA-DR5/DQw1 (29.1) and -DRw8/DQw1 (47.4) haplotypes were greater than the RRs of HLA-DR5 (10.4), -DRw8 (23.4) and -DQw1 (4.0) antigens. These results suggest that some specific HLA-DR/DQ haplotypes may be more important than the individual HLA-DR and -DQ phenotypes in the disease shift from RAS to the MC type of BC. [ABSTRACT FROM AUTHOR]

Expression of p53 protein was examined in oral squamous cell carcinoma (SCC) from patients who were areca quid (AQ) chewers and/or tobacco smokers, using anti-p53 antibodies with an immunoperoxidase technique. Positive p53 stain was observed in 47 of 81 (58%) cases of oral SCC, p53 overexpression was found to be higher in patients without AQ chewing and smoking habits than in patients with these two habits (80% vs 52%, P = 0.076). No significant correlation was found between p53 expression and the patients age, sex, cancer location, clinical staging, primary tumor TNM status, or histological differentiation of SCC. The Kaplan-Meier analysis showed that the prognosis for patients the p53-negative tumors was significantly better than that for patients with p53-positive tumors (P < 0.05). A significant correlation was also observed between positive lymph node status and poor prognosis (P < 0.05). These results suggest that p53 may serve as an adjuvant marker of poor survival in patients with oral SCCs in Taiwan. [ABSTRACT FROM AUTHOR]

Deposition of aerosol particles during sampling and transport through tubes has been studied by considering the effect of diffusion, sedimentation, inertial impaction and turbulent deposition. The pertinent equations are summarized and graphs presented showing particle deposition as a function of particle size, tube diameter and length, and flowrate. The influence of electric charge on particle deposition has been studied by measuring the penetration of monodisperse. charged aerosols through metal and plastic tubings. The result has been expressed in terms of a mean surface electric field on the plastic tubing surfaces. For Polyflo® and Teflon®, the mean surface electric field has been found to be in the vicinity of 50–200 V cm and, for Tygon®, essentially zero. The surface electric charge on several commonly used filters has also been measured and the influence of this charge on particle deposition in the filter-housing during sampling has been studied. [ABSTRACT FROM PUBLISHER]

Five cases of oral malignant fibrous histiocytoma (MFH) in patients who had previously received radiotherapy in the head or neck region were included in this study. There were 3 men and 2 women. Four patients had been irradiated for nasopharyngeal carcinoma (NPC) and the other for a squamous cell carcinoma (SCC) involving the tongue and mouth floor. The MFH developed 2.5-11 years after the initial radiotherapy. Two cases of MFH occurred in the maxilla, two in the mandible, and the remaining one in the tongue, floor of mouth and mandible. Clinically, the oral post-radiation MFH presented as tender, reddish, elastic, lobulated masses with surface ulceration. Radiographic examination of the involved jaws revealed a poorly defined radiolucent lesion without any periosteal or endosteal reaction. The prognosis of these tumors was very poor. Although aggressive multimodality treatment had been applied, 3 of 5 patients eventually died of the disease, with a mean survival time of 17 months after establishing the diagnosis of MFH. In order to ensure the early diagnosis and treatment of this radiation-induced second malignancy, close oral follow-up is mandatory for patients who have received radiotherapy for head and neck malignancies. [ABSTRACT FROM AUTHOR]

Presents on statistics of children with cancer on a specified age bracket and their visioned futures and dreams. Need for nurses to understand the hopes and dreams of children with cancer; Thrapeutic nursing process of nurses for cancer patients particularly in children; Procedures involved in coming up with the needed information from cancer patients.

A new ferrite-ceramic composite material with inductive, capacitive, and impedance properties was fabricated by a solid-state reaction. The composite materials were prepared with ferromagnetic NiCuZn ferrites and ferroelectric BaTiO3 perovskite. Co2+, Bi3+, Y3+, Dy3+, and Ca2+ ions are selected to improve the electromagnetic properties. We found that this new material has excellent frequency dependence of magnetic and dielectric properties, which can be used not only as inductor and resistor materials but also as capacitor materials in the wide range of 1 KHz to 4 GHz. At 1 MHz, the dielectric constant ϵ' of the composite material is 60-120, and the initial permeability μ' is 5.6-13. [ABSTRACT FROM AUTHOR]

The direct conversion of CO2 to aromatics is an effective strategy for simultaneously achieving carbon neutrality and its resource utilization. However, it is a great challenge to efficient CO2 conversion to high value-added aromatics due to the chemical inertness and characteristics of multi-path conversion of CO2. In this work, a series of nanosized ZSM-5 zeolites [NZ5(x)] with different acid amount and strength were synthesized by a seed-induced template-free method via changing the initial gel composition. The Cr2O3 nanoparticle was prepared by simple precipitation method. The performance of the Cr2O3/NZ5(x) bifunctional catalysts composed of Cr2O3 and nano-ZSM-5 zeolites with different acidity, and mixed Cr2O3 with NZ5 (50) by different ways in the CO2 hydrogenation reaction was investigated. The Cr2O3/NZ5(50) catalyst with suitable acidity and closest metal-acid site distance exhibit the highest aromatics selectivity of 87.2% among all hydrocarbon products at CO2 single-pass conversion of 13.6%, which is due to the synergistic effect between the acid sites of the nanosized ZSM-5 zeolite and metal sites provide by Cr2O3 with abundant oxygen vacancies. [ABSTRACT FROM AUTHOR]