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A new bilayer-structured photoelectrode film with spherical TiO2 nanorod aggregates as a light-scattering overlayer and nanocrystalline TiO2 as an underlayer is fabricated and studied with the aim of improving energy conversion efficiency in dye-sensitized solar cells (DSSCs). An overall energy conversion efficiency of 6.10% and a short-circuit photocurrent density of 18.47 mA cm−2 are achieved by introducing a spherical TiO2 nanorod-aggregate light-scattering layer. These are respectively 37.1% and 42.6% higher than those of a DSSC using a conventional 200 nm-diameter solid TiO2 particle light-scattering layer. These improvements are attributed to the spherical TiO2 nanorod-aggregate overlayer, which has a large surface area for sufficient dye adsorption, sub-micrometer size for efficient light scattering, and lower surface state traps, allowing a longer exciton lifetime.

Primarily, this paper introduces a framework for all-day service traffic which states recognition in traffic monitoring videos without vehicle segmentation. It proposes the average intensity of background subtract image, which is named as gray characteristic. This is a new feature to describe the amount of vehicle running on the road, and proves that there is a linear correlative relationship between the gray characteristic and the occupation ratio. Meanwhile it also presents a vehicle corners extraction method without vehicle segmentation. Secondly, this paper suggests an algorithm of Gaussian group-based histogram (GBH) to build the background; and states the average intensity of road in background which is named as illumination characteristic. This can be used as a feature to distinguish different traffic scenes. A group of classifiers are designed to recognize the traffic state in different traffic scenes to acquire all-day traffic states. Finally, by using the method presented in this paper to recognize traffic state, the vehicle segmentation is not required, thus reduces the computation complexity and enhances the robustness of system. After a suite of reasonable test, this method can recognize traffic state all-day in real-time, and the classification of the method can achieve a higher coincide ratio with human classification.

Recently, the manufacturers of life-jacket are very interested in the acquisition of USCG(US Coast Guard) approval because the acquisition of USCG approval has an important role in the purchasing decision of the buyer`s. Be based on criterion of USCG, we studied how to predict the change of floating position of human model with life-jacket to verify the backside restore. For this, in this study, the human model and the lifejacket was modeled in three dimension, the application program for prediction of floating position was developed, and plugged-in commercial program.

Carbon nanotubes-alumina (CNTs-Al2O3) composite ceramics with 25vol% CNTs were fabricated by sol-gel method and followed by hot-pressing. The resultant ceramics and powders were characterized for their microstructure and composition by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), and infrared spectra (IR). The mechanical properties of the ceramics were measured by micromechanical testing system (MTS). The results show that both ultrasonic calefaction process during the gelation of alumina sol and annealing process during the sintering can remarkably enhance the fracture toughness and flexural strength of CNTs-Al2O3composite ceramics, compared with the composite ceramics without undergoing these processes. It is believed to be due to the relatively uniform dispersion of CNTs and the lower thermal stress in the matrices.

Hydroxyl magnesium silicate powders were prepared by planetary-milling machine and a certain amount of No.46 mechanical oil was canned into the stainless steel vial in order to investigate its influence on the size of particles. The tribological properties of the powders in the oil were investigated on a four-ball machine. The morphologies and the chemical components of the worn surfaces were characterized by means of scanning electron microscopy (SEM) and energy dispersive spectroscopy (EDS). The ball milling results showed that the adding of mechanical oil decreased the cold welding and agglomeration, finally, fine silicate powders of 2μm in mean size were made. The tribological test results showed that the extreme pressure and antiwear properties of No.46 mechanical oil were improved by the additive obviously. The lubrication mechanism is inferred that a boundary lubrication film is formed and the tribochemical reactions occur on the friction surfaces due to the active agents in the silicate crystal, thus it can be seen that the silicate powders is a new and enviroment friendly lube additive.

In this study, α-alumina/multi-walled carbon nanotube (α-Al2O3/MWCNT) composite ceramics with 5 wt.% CNTs additions were synthesized using ball-milled and hydrothermal crystallization methods, respectively, followed by hot-pressing. The mechanical properties and oxidation resistance of the two types of composite ceramics were measured using micromechanical testing system, thermogravimetry, and differential scanning calorimetry. Compared with monolithic Al2O3 ceramic, the fracture toughness and flexural strength of the composite ceramics synthesized using ball-milled method were improved by 61.1% and 17.2%, respectively due to the distinct “pinning” effect of MWCNTs, and the other type of composite ceramics’ were improved by 80.3% and 24.6% due to the obvious pull-out effect of the ceramic-coated MWCNTs and the smaller grain size. At the same time, the weight losses of the ceramic samples exposed to air at 1000 °C for 1 h were inconspicuous. It indicates the composite ceramics have excellent oxidation resistance.

Novel high-performance Ni-rGO coated polymer (NiGP) foams for EMI shielding were developed with a dip-coating and reduction method. The obtained NiGP3 foams with a thickness of 10 mm prepared by 3 rounds of dip-coating, exhibited excellent EMI shieling effectiveness (EMI SE) of 24.03−27.71 dB at 30−1500MHz, which can fully meet the requirement of practical application. Furthermore, the NiGP foams maintain the compressibility of the original polymer foams.

Visible-light-induced BiVO4-SiO2 composites photocatalysts with monoclinic scheelite structure were successfully synthesized via a sol-gel method, and were characterized with XRD, XPS, DRS, SEM and BET. The result indicated that BiVO4-SiO2 composite photocatalysts exhibited relatively high BET surface areas, consisting of primary nanocrystals with average size of 44 nm. The band gap of the sample was estimated to be 2.56 eV, representing an obvious blue-shift compared with that of the SSR-BiVO4 sample. The photocatalytic activities were also evaluated by decolorization of methylene blue (MB) under blue light. The photodegradation rate of BiVO4-SiO2 composite photocatalysts was quite high, up to 69% in 2 h, which was much better than that of the reference sample prepared by solid-state reaction (5.5%) under the same conditions.

Alumina/carbon nanotubes (Al2O3/CNTs) composite coating was synthesized by plasma spray employing mixtures of Al2O3-coated CNTs and nano-sized α-Al2O3 at atmosphere. This coating was characterized for the microstructure and the composition by X-ray diffraction (XRD), energy-dispersive X-ray spectroscopy (EDS), high resolution transmission electron microscopy (HRTEM), thermo gravimetric analysis (TG), differential scanning calorimetry analysis (DSC) and scanning electron microscopy (SEM). The results show that the thickness of the coating is about 0.5mm and the constituent elements were changed to α-Al2O3, CNTs and γ-Al2O3 duo to the superhigh temperature during the plasma spray process. The great mass of the mixtures were melted well and the CNTs were dispersed uniformly in the melted ceramic. The oxidation resistance and the microwave absorption properties were discussed simply to describe the functions of the composite coating.

Electrical explosion of wire has a prosperous future in fine powder producing. In the process of electrical explosion of segmented metal wire (EESW),energy deposited in the wire was influenced by process variables such as the initial charging voltage of the capacitors, the length and the diameter of the segmented wire,and the electrode spacing. For understanding their relation completely, a series of experiments of electrical explosion was carried out with variations of the initial charging voltage and the segmented wire lengths and diameter. Results show that, energy deposition efficiency was weakly dependent on the wire length , whereas it has a strong dependence on the wire diameter, the initial charging voltage of the capacitors have an important influence on the energy deposition.

Multi-walled carbon nanotubes (MWCNTs) were coated with a nano-sized α-alumina polycrystalline layer by hydrothermal crystallization under autoclave conditions followed by manipulative calcination. These nanocomposites were characterized for their microstructure and composition by X-ray diffraction (XRD), energy-dispersive X-ray spectroscopy (EDX), transmission electron microscopy (TEM), high resolution transmission electron microscopy (HRTEM) and scanning electron microscopy (SEM). The results show that the microcrystalline α-alumina layer with the thickness of 1–3 nm was rough and compact, which profited from well adhesion by boehmite sol, the lower temperature for the conversion of the hydroxide to oxide, and the slower speed for the calefaction process. In addition, the α-alumina-coated MWCNTs were dispersed uniformly in alumina particles.

When components overlap, the aircraft multiple-hit vulnerability analysis usually consists of two steps. The first is to determine the aircraft unique existent states using vulnerable area decomposition method, and the second is to calculate the aircraft cumulated probability of kill using Markov chain method for exact solution or Monte Carlo method for solving the combinatorial explosion problem. This article proposes a direct simulation method for calculating the aircraft multiple-hit vulnerability in order to avoid the complex vulnerable area decomposition issue. In this method, random method is adopted to produce the multiple-hit locations and Bernoulli trial is used to determine the kill or no kill of each component hit by one shot line, and kill tree is checked to determine aircraft existent states during one simulation. When the number of times of simulation is large enough, the aircraft multiple-hit vulnerability can be statistically obtained. Analysis shows that the proposed direct simulation method can provide good accuracy compared with Markov chain method and avoid the combinatorial explosion problem, and does not need the complex vulnerable area decomposition and can directly calculate the aircraft multiple-hit vulnerability. Another important finding is the binomial or Poisson simplified approach is sometimes very poor in accuracy, and should be used cautiously.

This article, firstly, categorizes aircraft's presented area in a particular hit aspect into non-vulnerable region, non-overlapping vulnerable region and overlapping vulnerable region. Then, the aircraft's unique existing states are divided into kill states, intermediate states and no kill states. The parameters pertinent to aircraft's existing states in the above-mentioned regions are analyzed by using the shot line scanning method. Finally, the method provides two kinds of shot line geometric descriptive data: component's vulnerable area and presented area in each region, which can be used to calculate the component's single-hit vulnerability and aircraft's unique existing states and the areas corresponding to each state, which can be used to calculate the aircraft's single-hit and multi-hit vulnerability. Examples show that the proposed method can provide the parameters of the aircraft's or its component's area under threat being hit through tracing the shot line path thereby enabling the vulnerability calculated results to conform with reality to larger extent. In addition, the method solves the generality problem in dealing with overlapping components.

BACKGROUND The technique of intersphincteric resection of tumors combined with coloanal anastomosis has been used to avoid permanent colostomy for patients with a rectal cancer located < 5 cm from the anal verge. This study aimed at assessing the preservation of continence function of the residual rectum and the clinical prognosis of patients with lower rectal cancer after intersphincteric resection using a prolapsing technique. METHODS This study included patients with the following inclusion criteria: (1) pathological evidence of rectal cancer and the tumors within distal margins located 5 cm or less from the anus by preoperative endoscopic examination; (2) no evidence by MRI of infiltration of either the external sphincter, puborectalis or the levator muscle; (3) the patients are eligible for intersphincteric resection and lower coloanal anastomosis with a preoperative biopsy showing the tumors with well-to-moderate differentiation. From January 2000 to June 2004, 23 patients with low rectal cancer were included in this study. We used the standard abdominoperineal approach to perform radical resection of tumors with excision of the mesorectum and total or part of the internal sphincters. The patients were followed for assessment of the function of the residual rectum and of cancer recurrence after the operations. RESULTS The median tumor distance from the anal margin was 4.5 (range 3.5 - 5.0) cm and the mean distal surgical margin 1.6 (range 1.0 - 2.0) cm. Cancer was classified into Stage I (30.4%), Stage II (47.8%), and Stage III (21.7%) according to the TNM classification. Two patients developed anastomotic fistula after the surgical resection and 2 patients (8.7%) developed later stages of anastomotic stricture at the site of coloanal anastomosis. The median follow-up period was 31.5 months (range 12 - 54) and 2 patients (8.7%) developed local recurrence. Three deaths were associated with distal organ metastasis. Twenty patients (87.0%) have maintained competence to control solid or liquid stool and the capacity of flatus continence after the surgery. Among these patients, 2 patients were able to control solid stool and occasionally lose continence of liquid stool. And only 1 patient (4.4%) has retained partial rectum function with good continence of solid stool but not liquid after the operations. Average times of defecation per day of 3, 6, 12, 24 and 36 months after the surgery were 13.1, 4.7, 3.1, 2.9, and 3.2 times/day. Anal manometer measurements showed a decrease of pressure during the resting time after intersphincteric resection and this change remained during the period of follow-up. The maximum squeeze pressure was improved after an initial decrease after the surgery. CONCLUSIONS More residual rectum function after the surgery may be preserved by intersphincteric resection of low rectum cancer. At the same time this technique is safe with few postoperative complication and low tumor recurrence after the surgery.

The purpose of this study was to assess the accuracy of 3-T MRI in the preoperative diagnosis, staging, and planning of surgical management of rectal carcinoma.Thirty-eight patients (23 men, 15 women) with clinically suspected rectal carcinoma underwent 3-T MRI. Coronal, axial, and sagittal T2-weighted sequences with and without fat suppression; axial T1-weighted spin-echo sequences; axial T1-weighted gradient-echo sequences with and without fat suppression; oblique 2D MR hydrography; and 3D fat-suppressed dynamic contrast-enhanced MRI were performed. Image quality with these sequences was evaluated by three radiologists experienced in body MRI. The significance of difference in results with the sequences was tested. The manner in which MRI staging and feasibility of sphincter-sparing surgery agreed with operative and pathologic findings was evaluated with kappa statistics.Rectal carcinoma was identified on MRI and confirmed histologically in all 38 patients. MRI findings were correctly predictive of T category in 35 cases (accuracy, 92.1%). In 31 (96.9%) of 32 resectable cases,sphincter-sparing surgical approaches were accurately chosen on the basis of MRI findings. Among the 11 sequences, 3D fat-suppressed dynamic contrast-enhanced MRI best delineated tumor margins. Coronal and axial T2-weighted images also well depicted tumor margins with minimal artifact. T2-weighted images were superior to unenhanced T1-weighted images.MRI of rectal cancer at 3 T is accurate for prediction of T category and the feasibility of sphincter-sparing surgery. The best images were obtained with coronal, sagittal, and axial T2-weighted sequences and 3D fat-suppressed dynamic contrast-enhanced MRI.

This paper is concerned with congestion control for dynamic TCP/AQM networks with random delays. A robust congestion control algorithm is presented based on the H∞ approach, and the system performance is analyzed via linear matrix inequalities (LMIs). Simulation results illustrate the effectiveness of the proposed algorithm.

This paper deals with the optimal control problem by dynamic output feedback for rectangular descriptor system with disturbance. The design of dynamic output feedback contains two parts. The first one is given to make the rectangular descriptor system to be squared and the poles of the closed-loop system can be placed at arbitrarily approximation to the given positions. The other one is composed of Proportional-Integral (PI) observer and state feedback controller. The full-order PI observer which can estimate the state variables and disturbances is constructed to obtain the state information. Using the state information from the observer, the optimal disturbance rejection control law is proposed and the given quadratic performance index can be described in a simple form related to the solution and the initial value of the closed-loop system. Then a corresponding algorithm to minimize the quadratic performance index is proposed in which an optimal controller can be obtained. Finally, a numerical example is given to show the effectiveness and correctness of the proposed method.

A lot of time will be taken by the debugging and modification of the control algorithm deployed to the actual DCS in the complex factory environment. The actual object model of the boiler drum level control system can be simulated by Simulink. The DMC predictive control algorithm can be realized in the DCS by the CFC programming method. The communication with the DCS and Matlab can be implemented successfully via OPC, and the united simulation method can greatly shorten the cycle of the algorithm validation. The results show that the method has good effect in practice.

This paper investigates congestion control for Internet. A new congestion control model is established, which includes parameter uncertainties, external disturbances and time-varying state and input delays. And a new adaptive congestion controller is presented based on H ∞ control and online parameter estimation, which can compensate for such uncertainties, disturbances and time delays effectively, especially for the large time-varying parameter uncertainties. Simulation results are given to illustrate the effectiveness of the controller.

Microwave absorption materials such as traditional ferrite have received increasing attention owing to wide applications in national defense, electronics industry and physical electromagnetic protection. However, the insufficient absorption intensity coupled with the large application thickness have limited the practical application of the traditional materials in absorbing area. To address such issues, the PANI/Ni0.5Zn0.5Fe2O4 nanoparticles were fabricated, and the microscopic morphologies, x-ray diffraction (XRD) spectras, dielectric parameters and microwave absorption property of the as-prepared samples were charaterizated. The qualified absorption bandwidth (5.1 GHz) was remarkably broadened at a small thickness (1.78 mm), suggesting a novel platform for designing tunable qualified bandwidth lightweight absorbing materials.

Anastomotic leakage (AL) is a serious complication in laparoscopic rectal cancer surgery, and risk factors for AL are not well defined. Herein, we conducted a systematic review to quantify the clinicopathologic factors predictive for AL in patients who underwent laparoscopic anterior resection (LAR) for rectal cancer.A systematic search of electronic databases (PubMed, Embase, Cochrane CENTRAL, Scopus Database, and Wanfang Database) for studies published until August 2014 was performed. Cohort, case-control studies, and randomized controlled trials that examined clinical risk factors for AL were included.Fourteen studies (seven prospective and seven retrospective studies) involving 4580 patients met final inclusion criteria. From the pooled analyses, five demographic factors were found to be significantly associated with the development of AL, including male gender (OR 2.04, 95% CI 1.50-2.77), BMI ≥25 kg/m(2) (OR 1.46, 95% CI 1.00-2.14), ASA score2 (OR 1.74, 95% CI 1.04-2.93, P = 0.04), tumor size5 cm (OR 1.63, 95% CI 1.01-2.64, P = 0.05), and preoperative chemotherapy (OR 1.67, 95% CI 1.10-2.55, P = 0.02). Four operative factors were significantly associated with increased risk of AL, including longer operative time (95% CI 1.71-5.77, P = 0.0002), number of stapler firings ≥3 (OR 0.17, 95% CI 0.07-0.41, P0.001), intra-operative transfusions/blood loss100 mL (OR 3.79, 95% CI 2.48-5.49, P0.001), and anastomosis level within 5 cm from the anal verge (OR 9.63, 95% CI 3.05-30.43, P = 0.0001), while pelvic drain (OR 0.43, 95% CI 0.19-0.94, P = 0.04) was significantly associated with a lower AL rate.Our analysis identified several clinicopathologic factors associated with AL in patients who underwent LAR. The knowledge of these risk factors may influence treatment- and procedure-related decisions and possibly reduce the leakage rate.

This paper proposes a method for generating an optimal feature selecting sequence which is cost-effective for pattern classification. The sequence describes the order that feature selects for the process like classification. We model the procedure of feature selecting using Markov decision process (MDP), and use dynamic programming (DP) to learn a strategy to generate the orders only with the feedback of circumstance. To simplify the problem, we design a simple test scene that classifying three objects, whose values of synthetic features are generated randomly, into three classes. The results of experiments show that our method can reduce the computational time of extracting features.

This paper is concerned with adaptive control for discrete-time systems with time-varying uncertainties and time-varying delays in both state and control input. A new adaptive robust controller is presented based on the online parameter estimation and H ∞ approach. A numerical example and simulation results are given to verify the effectiveness of the proposed controller.

This paper presents a congestion controller in Internet, which is based on a discrete-time state space model with uncertainties, time-varying state and input delays and nonlinear disturbance. The controller is designed via robust H∞ control approach. Simulation results are given to show the effectiveness of the proposed controller.

This paper is concerned with congestion control in Internet. A new robust congestion control method is presented via model predictive control (MPC) based on a new state space model with uncertainties, external disturbances, and timevarying delays in both state and control input. The state feedback control law is obtained by using linear matrix inequality (LMI). Simulation results are given to show the effectiveness of the proposed method.

This paper considers power and rate control for wireless networks with time-varying delay. A delay-dependent robust power and rate control algorithm is presented via the H ∞ control approach. Simulation result shows that the proposed algorithm has good performance.

A novel power and rate control system model for wireless communication networks is presented, which includes uncertainties, input constraints, and time-varying delays in both state and control input. A robust delay-dependent model predictive power and rate control method is proposed, and the state feedback control law is obtained by solving an optimization problem that is derived by using linear matrix inequality (LMI) techniques. Simulation results are given to illustrate the effectiveness of the proposed method.

Since manipulating electromagnetic waves with electromagnetic active materials for environmental and electric engineering is a significant task, here a novel prototype is reported by introducing reduced graphene oxide (RGO) interfaces in carbon fiber (CF) networks for a hierarchical carbon fiber/reduced graphene oxide/nickel (CF-RGO-Ni) composite textile. Upon charaterizations of the microscopic morphologies, electrical and magnetic properties, the presence of three-dimensional RGO interfaces and bifunctional nickel nanoparticles substantially influences the related physical properties in the resulting hierarchical composite textiles. Eletromagnetic interference (EMI) shielding performance suggests that the hierarchical composite textiles hold a strong shielding effectiveness greater than 61 dB, showing greater advantages than conventional polymeric and foamy shielding composites. As a polymer-free lightweight structure, flexible CF-RGO-Ni composites of all electromagnetic active components offer unique understanding of the multi-scale and multiple mechanisms in electromagnetic energy consumption. Such a novel prototype of shielding structures along with convenient technology highlight a strategy to achieve high-performance EMI shielding, coupled with a universal approach for preparing advanced lightweight composites with graphene interfaces.

Species composition, seasonal changes in abundance and biomass of planktonic protozooplankton (ciliates, heliozoans and testaceans), and dynamics of the dominant species were investigated over more than two years in two shallow mesotrophic lakes. The macrophyte-dominated lake Biandantang had more protozoan species than the algal lake Houhu, and the two lakes had significantly different protozoan abundance and biomass patterns, compositions and dominants. On annual average, ciliates formed 81.13%, 91.10%, heliozoans 0.20%, 3.49%, and testaceans 18.67%, 5.42% of total protozoan biomass; the protozoans, in turn, formed 49.77%, 49.48% of total zooplankton biomass in lake Biandantang and Lake Houhu, respectively. With respect to ciliates, naked oligotrichs and Peritrichida (mainly 40–80 μm in size) dominated the abundance and Peritrichida dominated the biomass in Lake Biandantang, while Scuticociliatida (mainly smaller than 30 μm ) dominated the abundance and tintinnids dominated the biomass in Lake Houhu.

The species richness and seasonal development of planktonic ciliates were studied and compared in two shallow mesotrophic lakes, one covered with dense submerged macrophytes, the other macrophyte poor. Considerable differences in ciliate species composition, dominant taxa, abundance and biomass were observed. Ciliates were much more species rich in the macrophyte-rich lake, while they were more abundant numerically in the macrophyte-poor lake. Altogether, 96 species, included in 53 genera, 14 orders were identified. Among them, 80 species (included in 45 genera, 14 orders) observed from the macrophyte-rich lake, against 49 species (36 genera, 12 orders) were from the macrophyte-poor lake. In the macrophyte-rich lake, the mean abundance and biomass were 13.5 cells ml-1 and 547.10 μg l-1 f.w.; abundance and biomass were higher in spring and winter; naked oligotrichs dominated total ciliate abundance and Peritrichida dominated the biomass. In the macrophyte-poor lake, ciliate mean abundance and biomass were 35.5 cells ml-1 and 953.39 μg l-1 f.w.; abundances peaked in autumn; Scuticociliates dominated the abundance and Tintinnids dominated the biomass. Possible causes for the observed differences are discussed.

From April 1996 to October 1997, regular samplings were carried out monthly at 8 stations in a macrophytic basin of Baoan Lake. From the water samples, 47 genera, 96 species of ciliata were identified. Stations covered with macrophytes had greater number of ciliate species and higher percentage of sessile species. The mixotrophStrombidium viride bearing algal endosymbionts dominated numerically the whole ciliate communities; most of the other dominants were bactivores. Total ciliate density in Lake Baoan was 6170–34310 ind./L. The seasonal density fluctuations of the dominant species populations were also investigated. Maximum abundances were observed in spring and winter during the decay of macrophytes and minimum densities were observed during the summer months of luxuriant macrophytes growth.

Tailoring the architectures of spherical TiO2 aggregates is crucial to obtain superior photovoltaic properties and promote their application in dye-sensitized solar cells (DSSCs). Herein, we synthesized spherical TiO2 aggregates using different building units, including nanocrystallites, nanorods, nanosheets, and nanotubes, via a hydrothermal method, and studied the effect of the building units on the performances of DSSCs. The aggregates assembled by uniform nanosheet and nanotube building units were synthesized with the use of spherical TiO2 nanorod aggregates as titanium sources in an alkaline hydrothermal reaction. Compared with TiO2 nanoparticles, the spherical TiO2 aggregates possess higher surface area, more efficient light scattering ability, and better electron transport properties. Among the four types of spherical TiO2 aggregates; the nanorod, nanotube, and nanosheet aggregates demonstrate better electron transport properties than the nanocrystallite aggregates; the nanotube and nanosheet aggregates exhibit more efficient light scattering than the nanocrystallite and nanorod aggregates; and the nanotube aggregates show the highest surface area. Thus the DSSC based on nanotube aggregates exhibited the highest energy conversion efficiency of 7.48%, which is 16.0%, 9.7%, and 19.5% higher than those of the DSSCs based on the nanosheet, nanorod, and nanocrystallite aggregates, respectively.

This paper considers adaptive fault-tolerant power and rate control for wireless communication networks with transmitter faults, parameter uncertainties and bounded external disturbances. The adaptive fault-tolerant controller parameters are updated automatically through the on-line estimation of eventual faults to compensate for the fault effect on the network. It is proved that the resulting adaptive closed-loop system is uniformly bounded stable based on Lyapunov approach. Simulation results are given to demonstrate the effectiveness of the proposed controller.

Greater exposure to Pb(Ⅱ) increases the likelihood of harmful effects in the environment. In this study, the aquatic unicellular alga Chlorella protothecoides (C. protothecoides) and Chlorella vulgaris (C. vulgaris) were chosen to assess the acute and chronic toxicity of Pb(Ⅱ) exposure. Results of the observations show dose-response relationships could be clearly observed between Pb(Ⅱ) concentration and percentage inhibition (PI). Exposure to Pb(Ⅱ) increased malondialdehyde (MDA) content by up to 4.22 times compared with the control, suggesting that there was some oxidative damage. ANOVA analysis shows that Pb(Ⅱ) decreased chlorophyll (chl) content, indicating marked concentration-dependent relationships, and the lowest levels of chl a, chl b, and total-chl were 14.53, 18.80, and 17.95% of the controls, respectively. A real-time PCR assay suggests the changes in transcript abundances of three photosynthetic-related genes. After 120 h exposure Pb(Ⅱ) reduced the transcript abundance of rbcL, psaB, and psbC, and the relative abundances of the three genes of C. protothecoides and C. vulgaris in response to Pb(Ⅱ) were 54.66–98.59, 51.68–95.59, 37.89–95.48, 36.04–94.94, 41.19–91.20, and 58.75–96.80% of those of the controls, respectively. As for 28 d treatments, the three genes displayed similar inhibitory trend. This research provides a basic understanding of Pb(Ⅱ) toxicity to aquatic organisms. © 2013 Wiley Periodicals, Inc. Environ Toxicol 29: 1346–1354, 2014.