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Full-duplex techniques improve spectral efficiency in cellular networks by allowing a transceiver to simultaneously transmit and receive data with the same radio resource. To minimize self-interference and inter-node interference due to the deployment of full-duplex radio, users have to feed back their measurements of interference to allow the base station to effectively allocate resources and form transmission pairs. Considering that the interference measurements are private information, users may not report the true values and may try to gain their own benefits. To solve this problem, we propose a strategy-proof resource allocation mechanism for full-duplex cellular networks. The proposed scheme, which is based on auction and matching theories, guarantees that users report true values of their channel quality and utilities, and therefore guarantees the correctness of feedback information and the efficiency of resource allocation. Moreover, the proposed matching-based mechanism is theoretically proved to be stable and Pareto efficient. Simulation results confirm that, compared to a centralized scheme with non-truthful information from users, the proposed scheme can achieve an 11 $\%$ gain. [ABSTRACT FROM AUTHOR]

Vehicular fog computing (VFC) is a promising approach to provide ultra-low-latency service to vehicles and end users by extending fog computing to the conventional vehicular networks. Parked vehicle assistance (PVA), as a critical technique in VFC, can be integrated with smart parking in order to exploit its full potentials. In this paper, we propose a smart VFC system, by combining both PVA and smart parking. A VFC-aware parking reservation auction is proposed to guide the on-the-move vehicles to the available parking places with less effort and meanwhile exploit the fog capability of parked vehicles to assist the delay-sensitive computing services by monetary rewards to compensate for their service cost. The proposed allocation rule maximizes the aggregate utility of the smart vehicles and the proposed payment rule guarantees incentive compatibility, individual rationality, and budget balance. We further provide an observation stage with dynamic offload pricing update to improve the offload efficiency and the profit of the fog system. The simulation results confirm the win–win performance enhancement to the fog node controller, the smart vehicles, and the parking places from the proposed design. [ABSTRACT FROM AUTHOR]

Presents information on a study which characterized the optical-beam-control dynamics of torsion-beam deformable-mirror-device (DMD) spatial light modulators, to determine properties important to their operation. Description of the DMD architecture; Use of the optical beam deflection to measure the mechanical response of individual DMD pixels; Measurement of the DMD resonant frequency.

Deal selection on Groupon is a typical social learning and decision making process, where the quality of a deal is usually unknown to the customers. The customers must acquire this knowledge through social learning from other social medias such as reviews on Yelp. Additionally, the quality of a deal depends on both the state of the vendor and decisions of other customers on Groupon. How social learning and network externality affect the decisions of customers in deal selection on Groupon is our main interest. We develop a data-driven game-theoretic framework to understand the rational deal selection behaviors cross social medias. The sufficient condition of the Nash equilibrium is identified. A value-iteration algorithm is proposed to find the optimal deal selection strategy. We conduct a year-long experiment to trace the competitions among deals on Groupon and the corresponding Yelp ratings. We utilize the dataset to analyze the deal selection game with realistic settings. Finally, the performance of the proposed social learning framework is evaluated with real data. The results suggest that customers do make decisions in a rational way instead of following naive strategies, and there is still room to improve their decisions with assistance from the proposed framework. [ABSTRACT FROM PUBLISHER]

Device-to-device (D2D) communication could improve the efficiency of resource utilization in cellular networks by allowing nearby devices to communicate directly with each other. Nevertheless, one main challenge in D2D communication is resource allocation. We observed that the transmission quality in D2D communications can be significantly improved through a proper resource exchange. Based on this observation, we propose a novel D2D resource-allocation framework for a Long-Term Evolution Advanced (LTE-Advanced) system. We theoretically prove that any arbitrary algorithm, either distributed or centralized, will converge in the proposed framework whenever all performed exchanges are beneficial. Based on the concept of beneficial exchange, we propose a trader-assisted resource exchange (T-REX) mechanism, which is an exchange-based mechanism that converges in polynomial time and achieves Pareto optimality as an efficient and flexible solution to the D2D resource-allocation problem. The Evolved NodeB (eNodeB) regulates the D2D resource allocation through designing the trader preference functions in the T-REX mechanism. By applying game-theoretic analysis to the D2D communication system, we prove that all rational D2D pairs will truthfully report their information when the trader preference functions are properly designed. Finally, our simulation results show that the proposed T-REX mechanism significantly mitigates the interference experienced by D2D devices in LTE-Advanced systems. [ABSTRACT FROM PUBLISHER]

Background: Oral submucous fibrosis (OSF) is a chronic oral mucosal disease characterized by progressive deposition of collagen in the subepithelial connective tissue and epithelial atrophy. Previous studies have shown that at 330-nm excitation, the 380- and 460-nm emission peaks of the auto-fluorescence spectra for oral mucosal tissues reflect the collagen content in the subepithelial connective tissue and the nicotinamide adenine dinucleotide phosphate (NADH) content in the epithelial cells, respectively. Therefore, at 330-nm excitation OSF mucosa may have a higher 380-nm emission peak and a lower 460-nm emission peak than the normal oral mucosa (NOM).Methods: To test the above hypothesis, we measured the in vivo auto-fluorescence spectra of 59 OSF mucosal sites and compared the measured spectra with auto-fluorescence spectra obtained from 15 NOM samples from 15 healthy volunteers, five samples of friction hyperkeratosis (histologic diagnosis, hyperkeratosis and acanthosis) on OSF buccal mucosa (FHOSF), and 29 samples of oral leukoplakia (histologic diagnosis, hyperkeratosis and acanthosis) on OSF buccal mucosa (OLOSF).Results: We found that the spectrum of the OSF mucosa had a significantly higher 380-nm emission peak and a significantly lower 460-nm emission peak than the spectra of NOM, FHOSF, and OLOSF samples. When the mean (+/-SD) fluorescence intensities at 380 +/- 15 nm (I380 +/- 15 nm) and 460 +/- 15 nm (I460 +/- 15 nm) emission peaks and the mean ratio of I460 +/- 15 nm/I380 +/- 15 nm were compared between groups, we found that OSF group had a significantly higher mean value of I380 +/- 15 nm, a significantly lower mean value of I460 +/- 15 nm, and a significantly lower mean ratio of I460 +/- 15 nm/I380 +/- 15 nm than the NOM, FHOSF, and OLOSF groups (P < 0.001). However, no significant differences in the mean values of I380 +/- 15 nm, I460 +/- 15 nm, and ratio of I460 +/- 15 nm/I380 +/- 15 nm were found between NOM and FHOSF or OLOSF samples as well as between FHOSF and OLOSF samples (P > 0.05).Conclusion: Because OSF mucosa has a very unique pattern of auto-fluorescence spectrum, we conclude that auto-fluorescence spectroscopy is a good method for real-time diagnosis of OSF. [ABSTRACT FROM AUTHOR]

Background: Our previous ex vivo study has shown that autofluorescence spectroscopy at 330-nm excitation can discriminate specimens of normal buccal pouch mucosa (normal), epithelial hyperkeratosis (hyperkeratosis), epithelial dysplasia (dysplasia), and squamous cell carcinoma (SCC) taken from DMBA-treated hamsters by using the method of partial least-squares discriminant analysis (PLSDA).Methods: This study used a fiber optics-based fluorescence spectroscopy system to measure the autofluorescence spectra of 23 normal, 14 hyperkeratosis, 28 dysplasia, and 10 SCC samples in vivo. PLSDA with cross-validation was used to analyze the autofluorescence spectral data of all samples.Results: We found that at 330-nm excitation, the autofluorescence spectra of all samples had two main peaks: one at 380 nm and the other at 460 nm. The hyperkeratosis samples had a higher 380-nm emission peak (EP) and a lower 460-nm EP than normal samples. On the contrary, the dysplasia samples had a lower 380-nm EP and a higher 460-nm EP than normal samples. Furthermore, the SCC samples had a much lower 380-nm EP and a much higher 460-nm EP than all other samples. To quantify the spectral changes during the progression of oral carcinogenesis, ratios of the area under the spectrum of 380 +/- 15 nm to that under the spectrum of 460 +/- 15 nm (denoted as A(380 +/- 15 nm)/A(460 +/- 15 nm)) for all samples were calculated. The mean ratio values of A(380 +/- 15 nm)/A(460 +/- 15 nm) decreased gradually from hyperkeratosis to normal, to dysplasia, and to SCC samples. Significant differences in this mean ratio were found between any two groups of normal, hyperkeratosis, dysplasia, and SCC samples. By choosing proper thresholds, PLSDA with cross-validation could provide an accurate identification rate of 86% for hyperkeratosis, of 87% for normal, and of 89% for dysplasia samples. In addition, by choosing a proper threshold, we could separate benign (normal and hyperkeratosis) from dysplasia or SCC tissues with a sensitivity of 92% and a specificity of 95%.Conclusion: Our results indicate that the autofluorescence spectroscopy technique is a useful diagnostic tool for in vivo diagnosis of oral pre-cancers and cancers in DMBA-induced hamster buccal pouch carcinogenesis model. [ABSTRACT FROM AUTHOR]

Nonpoint source pollution from urban areas has been identified as a leading contributor to impaired water quality. Floating treatment wetlands (FTWs) are cultivated plants growing on floating mats in open water. FTWs can be used to remove pollutants from runoff, but data on their effectiveness is limited. We conducted a field study of FTWs in a nutrient enriched urban wet pond to investigate vegetation biomass and phosphorus (P) accumulation/distribution, sustainability under ice encasement stress (which is a concern in temperate regions), and to assess the use of the FTW by species. Planted perennial macrophytes successfully adapted to stresses of the low dissolved oxygen (DO) concentrations (minimum: 1.2 mg/L) in summer, ice encasement in winter, and relatively low nutrient concentrations in the water (median: 0.15 mg/L TP and 1.15 mg/L TN). Pickerelweed produced more biomass and demonstrated higher P removal performance (10.44 g dry weight/plant and 7.58 mg P/plant) than softstem bulrush (2.20 g dry weight/plant and 1.62 mg P/plant). Based on the observed seasonal changes in biomass and P, we recommend harvest of above-ground vegetation is conducted in June for maximum P removal or in September to prevent P release due to senescence. Submerged tissues of pickerelweed, softstem bulrush, and yellow iris ( Iris pseudacorus ) survived ice encasement and regrew in the second year. Additionally, plant diversity increased during the study period through recruitment of both native and exotic wetland plants. Systematic observation of wildlife activities indicated eight classes of organisms inhabiting, foraging, breeding, nursing, or resting in the FTWs. This study suggests above-ground plant harvest can enhance P removal, and that softstem bulrush, yellow iris, and pickerelweed can be sustained over winter on the FTW. Future study is recommended to investigate the feasibility of multiple vegetation harvest and document the possible habitat creation by the use of FTWs. [ABSTRACT FROM AUTHOR]

Floating treatment wetlands (FTWs) consist of emergent macrophytes that are placed on a floating mat in a pond for water treatment and aesthetic purposes. FTWs may have unique advantages with respect to treating urban runoff within existing retention ponds for excess nutrients. However, research is lacking in providing guidance on performance of specific species for treating urban runoff, and on timing of harvest. Harvesting is needed to remove nutrients permanently from the retention pond. We investigated vegetation effects on FTWs on nitrogen (N) and phosphorus (P) removal performance and storage in above-ground FTW macrophyte tissues. The study evaluated pickerelweed (PW, Pontederia cordata L.) and softstem bulrush (SB, Schoenoplectus tabernaemontani ) over time in microcosms flushed with water obtained from a nearby urban retention pond in northern Virginia near Washington, DC. While the literature exhibits a wide range of experimental sizes, using the term mesocosm, we have chosen the term microcosm to reflect the small size of our vessel; and do not include effects of sediment. The experiment demonstrated PW outperformed SB for P and N removal. Based upon analysis of the accumulated nutrient removal over time, a harvest of the whole PW and SB plants in September or October is recommended. However, when harvesting only the aerial parts, we recommend harvesting above-ground PW tissues in July or August to maximize nutrient removal. This is because PW translocates most of its nutrients to below-ground storage organs in the fall, resulting in less nutrient mass in the above-ground tissue compared to the case in the summer (vegetative stage). Further research is suggested to investigate whether vegetation can be overly damaged from multiple harvests on an annual basis in temperate regions. [ABSTRACT FROM AUTHOR]

Abstract: The application of floating treatment wetlands (FTWs) in point and non-point source pollution control has received much attention recently. Although the potential of this emerging technology is supported by various studies, quantifying FTW performance in urban retention ponds remains elusive due to significant research gaps. Actual urban retention pond water was utilized in this mesocosm study to evaluate phosphorus and nitrogen removal efficiency of FTWs. Multiple treatments were used to investigate the contribution of each component in the FTW system with a seven-day retention time. The four treatments included a control, floating mat, pickerelweed (Pontederia cordata L.), and softstem bulrush (Schoenoplectus tabernaemontani). The water samples collected on Day 0 (initial) and 7 were analyzed for total phosphorus (TP), total particulate phosphorus, orthophosphate, total nitrogen (TN), organic nitrogen, ammonia nitrogen, nitrate-nitrite nitrogen, and chlorophyll-a. Statistical tests were used to evaluate the differences between the four treatments. The effects of temperature on TP and TN removal rates of the FTWs were described by the modified Arrhenius equation. Our results indicated that all three FTW designs, planted and unplanted floating mats, could significantly improve phosphorus and nitrogen removal efficiency (%, E-TP and E-TN) compared to the control treatment during the growing season, i.e., May through August. The E-TP and E-TN was enhanced by 8.2% and 18.2% in the FTW treatments planted with the pickerelweed and softstem bulrush, respectively. Organic matter decomposition was likely to be the primary contributor of nutrient removal by FTWs in urban retention ponds. Such a mechanism is fostered by microbes within the attached biofilms on the floating mats and plant root surfaces. Among the results of the four treatments, the FTWs planted with pickerelweed had the highest E-TP, and behaved similarly with the other two FTW treatments for nitrogen removal during the growth period. The temperature effects described by the modified Arrhenius equation revealed that pickerelweed is sensitive to temperature and provides considerable phosphorus removal when water temperature is greater than 25 °C. However, the nutrient removal effectiveness of this plant species may be negligible for water temperatures below 15 °C. The study also assessed potential effects of shading from the FTW mats on water temperature, DO, pH, and attached-to-substrate periphyton/vegetation. [Copyright &y& Elsevier]

Abstract: This paper demonstrates a simple and easy approach for the one-step synthesis of Fe3O4-chitosan composite particles with tadpole-like shape. The length and diameter of the particles were adjustable from 638.3μm to ca. 798μm (length), and from 290μm to 412μm (diameter) by varying the flow rate of the dispersed phase. Mitoxantrone was used as the model drug in the drug release study. The encapsulation rate of the drug was 71% for chitosan particles, and 69% for magnetic iron oxide-chitosan particles, respectively. The iron oxide-chitosan composite particles had a faster release rate (up to 41.6% at the third hour) than the chitosan particles (about 24.6%). These iron oxide-chitosan composite particles are potentially useful for biomedical applications, such as magnetic responsive drug carriers, magnetic resonance imaging (MRI) enhancers, in the future. [Copyright &y& Elsevier]

Highlights: [•] Develops a unique model of integrated floating treatment wetland (i-FTW) systems. [•] Model incorporates water body characteristics and FTW coverage to simulate i-FTWs. [•] A bootstrap method is used to generate predictions and estimate uncertainty. [•] First order kinetics is a simplified approach that adequately predicts performance. [•] The model fits FTW literature data (2009–2012) well. [Copyright &y& Elsevier]

Abstract: A pulsatile ultrasound controlled drug release platform with diclofenac-loaded alginate microcapsules (fabricated with a home-made electrostatic device, 75% embedded rate) was established to evaluate anti-inflammation efficiency. Better anti-inflammation efficiency was found using the ultrasound system and the drug delivery can be adjusted based on the programmed ultrasound cycle. The results of the in vitro study show that an approx. 30% higher drug release rate was obtained by using continuous ultrasound irradiation (9-Watt, 180 min), and an approx. 16% higher drug release rate was obtained by using pulsatile ultrasound irradiation (9-Watt, 60 min) compared to without ultrasound activation. For the in vivo study, the anti-inflammatory test with carrageenan-induced rat’s paw edema shows that diclofenac-loaded microcapsules followed by ultrasound irradiation (9-Watt, 60 min) contributed to an 81% inhibition rate, which was significantly higher than diclofenac only (approx. 60% higher). In addition, because of their heat conducting properties, gold nanoparticles encapsulated in the diclofenac-loaded microcapsules resulted in better drug release efficiency, but tended to depress the anti-inflammation effect. [Copyright &y& Elsevier]

The IEEE 802.11-based WiFi wireless technology is one of the most promising technologies to provide ubiquitous networking access. The IEEE 802.11 working group has always strived to improve this wireless technology through creating new amendments to the base 802.11 standard. Recently, IEEE 802.11n amendment was created to enhance 802.11 for higher throughput operation. Not only new Physical Layer enhancements are standardized, but new Medium Access Control Layer mechanism are also defined. In this paper, we examine the network performance enhancement by the proposed 802.11n MAC layer features: aggregation, block acknowledgement, and reverse direction mechanism. We implemented a new 802.11n module in the NS-2 simulation platform. The simulation results demonstrated the effectiveness of 802.11n MAC layer enhancement. VoIP performance is effectively improved with 802.11n MAC enhancement. [ABSTRACT FROM AUTHOR]

Abstract: Various light-emitting diodes (LEDs) with different light wavelengths and illumination intensities were employed to explore the effects of light source on photoautotrophic cultivation of Spirulina platensis. From the experimental results, red LED exhibited the highest specific growth rate of 0.40 (day−1) under the condition of 3000μmolm−2 s−1. Blue LED showed the least efficiency in the conversion of photon to biomass. Hence, a modified Monod model was proposed to fit the specific growth rates of S. platensis from different light sources. The light intensity threshold for minimum photoautotrophic growth was also determined. In comparing the economic efficiency of energy to biomass, the use of red LED gave the most effective performance for the photoautotrophic cultivation. [Copyright &y& Elsevier]

Acupuncture has been shown as an effective traditional Chinese medicine treatment method, especially for pain relief. Recently, laser acupuncture is becoming increasingly popular, thanks to its noninvasive and painless nature and effectiveness in treating diseases, proven by many studies (for example, some previous studies showed that low-power laser stimulation is able to increase the power of alpha rhythms and theta waves). In our prior work, we developed a novel laser acupuncture model that emulates lifting-and-thrusting operation commonly used in traditional needle acupuncture and showed its benefit in improving cardiac output and peripheral circulation. By extending our previous studies, in this work, we perform extensive experiments to understand the effect of such a system on electrodermal activity (EDA) of acupoints, pulse characteristics, and brainwave, to further verify its efficacy. In particular, we found that laser stimulation could cause significant changes in EDA of acupoints, pulse amplitude, pulse-rate-variability (PRV), and acupoint conductance, as a function of laser power and stimulation time. In addition, laser acupuncture with the lifting-and-thrusting operation has more significant effect on increasing the power of alpha and theta frequency bands as compared to laser acupuncture without the lifting-and-thrusting operation. Finally, given sufficient stimulation time (e.g., > 20 min), the performance of a low-powered laser acupuncture with the lifting-and-thrusting operation could be comparable to that of traditional needle acupuncture. [ABSTRACT FROM AUTHOR]

Acupuncture plays an important role in traditional Chinese medicine (TCM) and is one kind of an inexpensive and effective treatment. However, some people might be reluctant to receive acupuncture treatment due to fear of pain. Laser acupuncture, thanks to its painless and infection-free advantages, has recently become an alternative choice to traditional acupuncture. The accuracy of acupuncture point positioning has a decisive influence on the quality of laser acupuncture. In this study, built on top of our prior work, we proposed a low-cost automated acupoint positioning system for laser acupuncture. By integrating several machine learning algorithms and computer vision techniques, we design and implement a robot-assisted laser acupuncture system on top of a smartphone. Our contributions include the following: (a) development of an effective acupoint estimation algorithm with a localization error less than 5 mm; (b) implementation of a smartphone-controlled automated laser acupuncture system with lift-thrust function, as a point-of-care device, that can be used by patients to relieve their symptoms at home. [ABSTRACT FROM AUTHOR]

In advanced technologies, on-chip-variation (OCV) has accounted for a large proportion of clock skew, which limits the performance of a circuit. To mitigate the OCV problem, a mesh structure has been widely used in high-performance designs. Unfortunately, clock mesh structure also causes large power consumption and large power-ground surge current. Therefore, recently, several approaches have been proposed to apply resonant clock to reduce power consumption. However, previous works often suffer from area overhead because of the need to insert large decoupling capacitors. In this paper, we propose a novel resonant clock mesh structure, called ping-pong mesh, to overcome these drawbacks. Our ping-pong mesh contains two submeshes, each of which plays the role of the decoupling capacitor of the other, and the clocks in two submeshes operate in completely opposite phases. Our ping-pong mesh has the following two advantages: 1) a ping-pong mesh does not need additional decoupling capacitors as in previous works and 2) a ping-pong mesh can reduce the power-ground surge current about half of previous works. Benchmark data consistently show that our ping-pong mesh does work well in practice. [ABSTRACT FROM AUTHOR]

Abstract: Light-emitting diodes (LEDs) with various light wavelengths (red, yellow, green, blue and white) and various levels of light intensity (750, 1500 and 3000μmolm−2 s−1) are applied to study the effects of light sources on chlorophyll a (Chl) and phycocyanin (Phy) production of Spirulina platensis. Logistic rate equations are used to depict the kinetic behavior of algal growth and pigments formation under various light sources and intensities. According to the regression results, a red LED is the best for algae growth. On the other hand, yellow light gives the best specific Chl production rate with a light intensity of 750 or 1500μmolm−2 s−1, and blue light yields the best specific pigments (for Chl and Phy) production rates at 3000μmolm−2 s−1. From the model fitting results, it is found that, at a higher light intensity, a higher specific Chl production rate accompanied by a higher S. platensis biomass is obtained. However, as for Phy production, a higher biomass results in a lower specific Phy production rate. The only exception is the use of blue light, which shows a positive effect on both Chl and Phy production rates under a higher light intensity. [ABSTRACT FROM AUTHOR]

Abstract: Influence of light-emitting diode (LED) light on antioxidant activity of radiated pea seedlings was first studied using red (625–630nm) and blue (465–470nm) LED lights as light sources in an attempt to determine and compare the changes in chlorophyll and β-carotene contents, and Trolox equivalent antioxidant capacity (TEAC, μM). After radiation for 96h, comparing to white light group, red light radiated seedlings displayed significant (p <0.05) increases in stem length and leaf area, while blue light radiation significantly (p <0.05) increased the stem length and seedling weight. Chlorophyll in leaves increased rapidly when seedlings were radiated by blue light but no significant (p >0.05) difference was observed among light radiated seedlings after 96-h cultivation. β-Carotene content of LED radiated leaves was significantly (p <0.05) higher in red light (54.47±2.35μg/g) group than in the others. TEAC value of ethanol and acetone extracts (50mg/mL) of 240 pieces of red light radiated seedlings cultured for 96h reached 106.48 and 81.68μM, respectively, were higher than the other treatments. In conclusion, the contribution of red light to significant β-carotene expression and antioxidant activity for nutrition and health benefits and blue light to seedling weight and chlorophyll induction of radiated pea seedlings are emphasized. [Copyright &y& Elsevier]

Light-induced fluorescence spectroscopy was conducted on human oral malignant and normal tissues. Under 330-nm excitation wavelength, significant differences in fluorescence intensity were observed around 380- and 460-nm emission. Furthermore, 7,12-dimethylbenz[a]anthracene (DMBA)-induced carcinogenesis in hamster buccal pouch was investigated to elucidate whether similar alterations of fluorescence spectroscopy occurred during the development of squamous cell carcinoma. Similar to the spectral profiles of human oral malignant and normal tissues, the most intense fluorescence peaks in the pouches occurred at 380 nm and 460 nm emission under 330 nm excitation wavelength. At 380 nm emission, the fluorescence intensity of normal pouch mucosa was stronger than those of DMBA-treated abnormal tissues at different stages of carcinogenesis. However, at 460 nm emission, the fluorescence intensity of DMBA-treated tissues was not only stronger than that of normal pouch mucosa but also shifted to 470 nm. These results suggest that under 330 nm excitation wavelength fluorescence spectroscopy may be useful for the detection of oral malignant lesions. [ABSTRACT FROM AUTHOR]