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The nonlinearity tolerance of several higher order modulation schemes, which make efficient use of transmission bandwidth, such as 8-PSK, 16-QAM, and 64-QAM, has been assessed for millimeter-wave fiber-radio systems using a Mach-Zehnder (MZ) modulator for the modulation of an optical carrier. Some other deteriorating factors, such as a bias-point shift in the MZ modulator and optical carrier leakage at the MZ filter, which is used for the separation of the two optical carriers, have also been considered. The assessment was accomplished through computer simulations. It is found that the effect of the nonlinearity of the MZ modulator is less serious for a system using 8-PSK than for a system using 16-QAM or 64-QAM, and that in the latter case, an optimal drive level exists for the modulator to achieve the best system performance. A bias-point shift, required in some deployment scenarios, degrades system performance significantly. A leakage of optical carrier to the wrong port at the MZ filter further degrades the system performance, especially for systems using the 16-QAM or 64-QAM modulation scheme. Index Terms - Fiber-radio, millimeter-wave, modulation, MZ modulation, nonlinearity.

Introduction: Salivary adenoid cystic carcinoma (SACC) is a frequent type of salivary gland cancer which is characterized by slow growth but high incidence of distant metastasis. We aimed to identify therapeutic targets which are associated with metastasis of SACC.Material and Methods: Total RNA was isolated from a low metastatic SACC cell line (ACC-2) and a highly metastatic SACC cell line (ACC-M), which was screened from ACC-2 by combination of in vivo selection and cloning in vitro. Then the total RNA was subjected to microarray analysis. Differentially expressed genes (DEGs) were screened from ACC-M compared with ACC-2, followed by Gene Ontology function and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analysis. Function annotation for DEGs also was performed. A protein-protein interaction network (PPI) was constructed for DEGs.Results: A total of 1128 DEGs were identified from ACC-M cells compared with ACC-2 cells. Both up- and down-regulated DEGs were enriched in different functions in biological process (BP), cellular component (CC) and molecular function (MF). Additionally, down-regulated DEGs were mainly enriched in "Apoptosis" and "Cytokine-cytokine receptor interaction" pathways which involved IFN-α1, NTRK1 and TGF-β1. In the PPI network, PIK3CA, PTPN11 and PIK3R1 had a number of nodes greater than 10.Conclusions: Transforming growth factor β1 might play a pivotal role during lung metastasis of SACC and be selected as a candidate target for treatment of metastatic SACC. IFNA1, NTRK1 and PIK3CA were also associated with tumor metastasis. [ABSTRACT FROM AUTHOR]

This paper investigates the H trajectory tracking control for a class of nonlinear systems with time-varying delays by virtue of Lyapunov-Krasovskii stability theory and the linear matrix inequality (LMI) technique. A unified model consisting of a linear delayed dynamic system and a bounded static nonlinear operator is introduced, which covers most of the nonlinear systems with bounded nonlinear terms, such as the one-link robotic manipulator, chaotic systems, complex networks, the continuous stirred tank reactor (CSTR), and the standard genetic regulatory network (SGRN). First, the definition of the tracking control is given. Second, the H performance analysis of the closed-loop system including this unified model, reference model, and state feedback controller is presented. Then criteria on the tracking controller design are derived in terms of LMIs such that the output of the closed-loop system tracks the given reference signal in the H sense. The reference model adopted here is modified to be more flexible. A scaling factor is introduced to deal with the disturbance such that the control precision is improved. Finally, a CSTR system is provided to demonstrate the effectiveness of the established control laws. [ABSTRACT FROM AUTHOR]

Aiming at the disadvantages of conventional mechanical cam; points or lines contact, highpressure, easy to wear, noise, difficult to machine, an electronic cam was designed. The cam motion characteristics, motion curve, motorcontrol, servo control was studied, a design of electronic cam control system based on Mitsubishi Q series PLC was proposed with double CPU servo control, which can deal with the sequential control and motion control, the control precision and control efficiency was improved. A closed loop control mode was employed. The servo-motor's position and speed instructions were calculated by the position encoder, which drive the push rod move straightly back and forth. At the same time, as a comparison with electronic cam, a mechanical cam structure was maded. The experiment results indicate that can any kinds of reciprocating motion can be gained by using the electronic cam. By adjusting the input curve of electronic cam, the effect of completely replacing the mechanical cam can be realized. [ABSTRACT FROM AUTHOR]

PURPOSE: To provide anatomical basis for clinical application of supraclavicular artery island flap. METHODS: The branch, origination, course, length and diameter of transverse cervical artery and supraclavicular artery were observed on 20 flaps from 10 adult cadavers perfused with lead oxide-gel, and the draining veins were observed too. The flaps were prepared imitatively on the cadavers. RESULTS: The transverse cervical artery originated from the thyrocervical trunk or subclavical artery and separated into deep branch and superficial branch above the middle third of the clavicle. The supraclavicular artery originated from superficial branch of the transverse cervical artery and extended backward and outward, and run over the surface of trapezius, acromial end of clavicle and deltoid fascia, and then penetrated the deep fascia and went into skin and subcutaneous tissue of supraclavicular and shoulder regions. The distance between the origins of the supraclavicular and transverse cervical arteries was on average (4.31±0.64)cm, and the distance between the origin of supraclavicular artery and the point where it penetrated the deep fascia was on average (3.62±0.42)cm. The external diameter of the transverse cervical artery was on average (2.71±0.33)mm, and the external diameter of supraclavicular artery was on average (1.10±0.17)mm. Two supraclavicular comitant veins run adjacent to the supraclavicular artery and drained into the transverse cervical vein and external jugular vein respectively. CONCLUSION: The supraclavicular artery island flap with supraclavicular artery as nutrient vessel is reliable for reconstruction of oral, maxillofacial and neck defects, and it can be used as a free flap that is equipped with a vascular pedicle that includes the transverse cervical artery. [ABSTRACT FROM AUTHOR]

Flight restraint is important for zoos, safaris, and breeding centers for large birds. Currently used techniques for flight restraint include both surgical and non-surgical approaches. Surgical approaches usually cause permanent change to or removal of tendon, patagial membrane, or wing bones, and can cause pain and inflammation. Non-surgical approaches such as clipping or trimming feathers often alter the bird's appearance, and can damage growing blood feathers in fledglings or cause joint stiffness. We observed microstructure of primary feathers of the red-crowned crane ( Grus japonensis) and found that the width of barbs is a determinative factor influencing vane stiffness and geometric parameters. We hypothesized that partial longitudinal excision of barbs on the ventral surface of the primary feathers would reduce the stiffness of the vane and render the feathers unable to support the crane's body weight during flight. Furthermore, we hypothesized that this modification of barbs would also change the aerodynamic performance of feathers such that they could not generate sufficient lift and thrust during flapping to enable the bird to fly. We tested this hypothesis on a red-crowned crane that had normal flight capability by excising the ventral margin of barbs on all 10 primaries on the left wing. The bird was unable to take off until the modified feathers were replaced by new ones. Removal of barbs proved to be a simple, non-invasive, low-cost and reversible method for flight restraint. It is potentially applicable to other large birds with similar structural characteristics of primary feathers. Zoo Biol 30:342-348, 2011. © 2010 Wiley-Liss, Inc. [ABSTRACT FROM AUTHOR]

PURPOSE: To study the feasibility of constructing marrow stomal cell-sheet and tissue engineering bone by combined marrow stromal cell-sheet technique and coral scaffold. METHODS: About 5x104 rabbit bone marrows stromal cells (BMSCs) were suspended in 200 μl of platelet-rich plasma (PRP), and the mixture was seeded and cultured on a plate. Marrow stromal cell-sheet was harvested after ten days of culture. The cell-sheets comprising multilayered BMSCs were wrapped around coral scaffolds, and cell-sheet-scaffolds constructs were transplanted under the skin of nude mice. Coral scaffolds loading BMSCs or coral scaffolds alone acted as control. The new bone formation was investigated by histology and histomorphometry 4 and 8 weeks after operation. SPSS 11.0 Software package was used for statistical analysis. RESULTS: New bone and cartilage formation was observed in specimens from both cell-sheet-scaffold constructs group and cell-scaffold constructs group in ectopic sites, and osteogenesis followed the pattern of endochondral bone formation, with moven bone matrix subsequently maturing into fully mineralized compact bone. Histomorphometric analyses showed enhanced cartilage and bone formation in cell-sheet-scaffold construct group 4 and 8 weeks after transplantation. No bone or cartilage formation could be observed in coral scaffold group. CONCLUSSION: Bone tissue similar to native bone may be regenerated utilizing marrows stromal cell-sheet technique in conjuction with coral scaffolds. [ABSTRACT FROM AUTHOR]

This paper proposes a new approach for multi-objective robust control. The approach extends the standard generalized l 2 (G l 2) and generalized H 2 (G H 2) conditions to a set of new linear matrix inequality (LMI) constraints based on a new stability condition. A technique for variable parameterization is introduced to the multi-objective control problem to preserve the linearity of the synthesis variables. Consequently, the multi-channel multi-objective mixed G l 2/G H 2 control problem can be solved less conservatively using computationally tractable algorithms developed in the paper. [ABSTRACT FROM AUTHOR]

In this study, surface sediment samples were collected from Dongting Lake, Honghu Lake, and Chihu Lake, and the concentrations of 10 heavy metals were measured. Then, the potential risk of heavy metal accumulation was evaluated using the cumulative pollution index ( I geo ), the enrichment factor (EF), and the potential ecological risk index (RI), and the sources were traced using correlation analysis (Pearson) and principal component analysis (PCA). The results showed that the pollution and potential ecological risk of Cd were the most serious. The mean values of Cd in East Dongting Lake, Honghu Lake, and Chihu Lake were 2.85, 1.59, and 3.57 mg·kg -1 , respectively. The concentrations of Cd were 25.87, 11.36, and 37.58 times higher than the soil background values of the corresponding provinces, which exceeded the risk screening value (0.6 mg·kg -1 ). Particularly, the Cd concentration of Chihu Lake exceeded the risk control value (3.0 mg·kg -1 ). Besides Cd, the concentration of As in Honghu Lake was also of concern. At the same time, the Cu, As, Zn, and Pb in Chihu Lake should not be neglected. The potential ecological risks of the three lakes were ranked as follows:Chihu Lake (RI=1 127)>East Dongting Lake (RI=831)>Honghu Lake (RI=421). The primary sources of heavy metals were industrial mining, agricultural production, and aquaculture, and some heavy metals (Mn and Cu) were from natural sources. This study was of great significance for the prevention and control of heavy metals in the sediments of typical lakes in the middle reaches of the Yangtze River.

To understand the pollution characteristics, spatial distribution characteristics, potential ecological risks, and sources of heavy metals in surface sediments of Dongjiang Lake, 12 surface sediment samples were collected from Dongjiang Lake. The contents of 20 heavy metals including Li, Be, V, Cr, Mn, Co, Ni, Cu, Zn, Ga, As, Se, Rb, Sr, Ag, Cd, Cs, Ba, Pb, and U were analyzed in this study. The geo-accumulation index method and potential risk index method were used to evaluate the pollution degree and potential risks of heavy metals in sediments, and the correlation analysis and principal component analysis were used to trace the source of the primary heavy metals. The results showed that the average contents of ω (Cd)(2.25 mg·kg -1 ) and ω (As)(80.80 mg·kg -1 ) in heavy metals of Dongjiang Lake sediments were 21.2 times and 5.5 times the background value (0.11 mg·kg -1 and 14.7 mg·kg -1 ) of Hunan province. The overall spatial distribution of heavy metals was in the order of South>North>Central. The evaluation by the geo-accumulation index method showed that Cd was at the heavy pollution level, As and Se were at the moderate pollution level, Ag and Ga were at the light pollution level, and the other heavy metals were below the pollution standard. The evaluation by the potential risk index showed that all the surface sediments of Dongjiang Lake were at the high-risk level. The main environmental risk factor was Cd, which had an extremely high risk; the second was As, which had a medium risk; and the remaining heavy metals had no ecological risk.

Objective: To investigate the method and efficacy of reconstruction of anterior mouth floor defects with depressor labii inferioris flap., Methods: Between March 2010 and August 2011, 4 patients with cancer in the anterior part of oral floor underwent tumour resection and simultaneous reconstruction with depressor labii inferioris flap. The patients were followed up for 2 - 18 months. The survival of the flaps, mobility of tongue and esthetic outcome of lip and mental region were evaluated., Results: All the flaps survived completely, tongues moved well, and functional and esthetic results were good., Conclusions: The depressor labii inferioris flaps are suitable for repairing defects of anterior oral floor.

Objective: To study the anatomy of supraclavicular artery island flap and report the clinical application of the island flap for the reconstruction of tongue defects., Methods: The branch, origination, course, length and diameter of transverse cervical artery and supraclavicular artery were observed on 20 flaps of 10 adult cadavers perfused with lead oxide-gel, and the draining veins were also observed. The supraclavicular artery island flaps were used to reconstruct the defects following tongue cancer ablation in 4 patients, and the data concerning functional impairment, aesthetic outcome and donor site morbidity were analyzed., Results: The transverse cervical artery were originated from the thyrocervical trunk or subclavical artery, and separated into deep branch and superficial branch above the middle third of the clavicle. The supraclavicular artery were originated from superficial branch of the transverse cervical artery and extended to backward and outward, and run over surface of trapezius, acromial end of clavicle and deltoid fascia, and then penetrated the deep fascia and go into skin and subcutaneous tissue of supraclavicular and shoulder regions. The distance between the origins of the supraclavicular and transverse cervical arteries was on average 4.3 cm, and the distance between the origin of supraclavicular artery and the point where it penetrated the deep fascia was on average 3.6 cm. The external diameter of the transverse cervical artery was on average 2.7 mm, and the external diameter of supraclavicular artery was on average 1.1 mm. Two supraclavicular comitant veins ran adjacent to the supraclavicular artery and drained into the transverse cervical vein and external jugular vein respectively. In the clinical study, 3 flaps survived completely and part of the skin paddle of the flap in one case exhibited necrosis. The contour and function of tongues were restored well and there was no limitation of shoulder motion in all 4 cases., Conclusions: The supraclavicular artery island flap with supraclavicular artery as nutrient vessel is reliable for reconstruction of oral, maxillofacial and neck defects, and it can be used as a free flap equipped with the transverse cervical artery.

Purpose: To evaluate the effect of intralesional injection of Pingyangmycin (PYM) for treatment of venous-venular malformation in the maxillofacial regions of children., Methods: The medical records of 306 patients with venous-venular malformation in the maxillofacial regions between January 1997 and June 2005 were reviewed. One hundred and twenty-three of the patients were men, and one hundred and eighty-three were woman, the sex ratio was 1:1.49. The patients aged from one month to 12 years, 172 were less than 6 months (56.21%). Pingyangmycin was injected into the center or in the vicinity of the venous-venular malformations, and repeated every 7 to 10 days. This cycle were repeated 3 to 5 times when necessary., Results: Three hundred and six patients were followed up for 6 to 102 months. Complete response was obtained in 156 cases (50.98%), partial response in 116 cases (37.91%), and improvement in 34 cases (11.11%). The overall response rate was 100%, and the curative rate was 88.89%., Conclusion: This method is safe, simple and effective for venous-venular malformation in the maxillofacial regions of children.

Objective: The effect of Pinyangmycin, Dexamethasonum and Sodium Morrhuate injected concomitantly to treat cavernous hemangioma in oral and maxillofacial regions was evaluated., Methods: The medical records of 350 patients with cavernous hemangioma in oral and maxillofacial regions between January 1998 and January 2002 were reviewed. One hundred and sixty-five of the patients were men, and 185 were women, the sex ratio was 1:1.12. The patients' ages were between 4 months and 55 years. Two hundred and Twenty-six hemangiomas were located in the maxillofacial regions, and 124 located in the oral cavity. The size of the lesions varied from 1 cm x 1 cm to 6 cm x 9 cm. Pinyangmycin, Dexamethasonum and Sodium Morrhuate were injected simultaneously into the lesions or in the vicinity of the cavernous hemangiomas, and the injection might be repeated every 5 to 7 days when necessary, and this process could be repeated 3 to 5 times., Results: Three hundred and fifty patients were followed up for 6-48 months. The cure and essentially cured rates were 95.48%, the total efficiency rate was 100%., Conclusion: This method was a safe, simple and effective therapy to manage cavernous hemangioma in the oral and maxillofacial regions.