Flexible resource allocation for joint optimization of energy and spectral efficiency in OFDMA multi-cell networks

The radio resource allocation problem is studied, aiming to jointly optimize the energy efficiency (EE) and spectral efficiency (SE) of downlink OFDMA multi-cell networks. Different from existing works on either EE or SE optimization, a novel EE-SE tradeoff (EST) metric, which can capture both the EST relation and the individual cells’ preferences for EE or SE performance, is introduced as the utility function for each base station (BS). Then the joint EE-SE optimization problem is formulated, and an iterative subchannel allocation and power allocation algorithm is proposed. Numerical results show that the proposed algorithm can exploit the EST relation flexibly and optimize the EE and SE simultaneously to meet diverse EE and SE preferences of individual cells.<br/

Cyclic intensive light exposure induces retinal lesions similar to age-related macular degeneration in APPswe/PS1 bigenic mice

<p>Abstract</p> <p>Background</p> <p>Intensive light exposure and beta-amyloid (Aβ) aggregates have been known as a risk factor for macular degeneration and an important component in the pathologic drusen structure involved in this disorder, respectively. However, it is unknown whether Aβ deposition mediates or exacerbates light exposure-induced pathogenesis of macular degeneration. Several studies including the one from us already showed accumulation of Aβ deposits in the retina in Alzheimer's transgenic mice. Using histopathological analysis combined with electroretinographic functional assessment, we investigated the effects of cyclic intensive light exposure (CILE) on the architecture of retina and related function in the APPswe/PS1bigenic mouse.</p> <p>Results</p> <p>Histopathological analysis has found significant loss of outer nuclear layer/photoreceptor outer segment and outer plexiform layer along with abnormal hypo- and hyper-pigmentation in the retinal pigment epithelium (RPE), remarkable choroidal neovascularization (CNV), and exaggerated neuroinflammatory responses in the outer retina of APPswe/PS1 bigenic mice following cyclic intensive light exposure (CILE), whereas controls remained little change contrasted with age-matched non-transgenic littermates. CILE-induced degenerative changes in RPE are further confirmed by transmission electron microcopy and manifest as formation of basal laminar deposits, irregular thickening of Bruch's membrane (BrM), deposition of outer collagenous layer (OCL) in the subretinal space, and vacuolation in the RPE. Immunofluorescence microscopy reveals drusenoid Aβ deposits in RPE as well as neovessels attached which are associated with disruption of RPE integrity and provoked neuroinflammatory response as indicated by markedly increased retinal infiltration of microglia. Moreover, both immunohistochemistry and Western blots detect an induction of vascular endothelial growth factor (VEGF) in RPE, which corroborates increased CNV in the outer retina in the bigenic mice challenged by CILE.</p> <p>Conclusions</p> <p>Our findings demonstrate that degenerative changes in the outer retina in the APPswe/PS1 bigenic mouse induced by CILE are consistent with these in AMD. These results suggest that an Alzheimer's transgenic animal model with accumulation of Aβ deposits might be an alternative animal model for AMD, if combined with other confounding factors such as intensive light exposure for AMD.</p

A Balanced Feed Filtering Antenna With Novel Coupling Structure for Low-Sidelobe Radar Applications

A fourth-order filtering patch antenna with a novel coupling structure is presented in this paper. Using the proposed coupling structure, both the balanced coupling feed and cross-coupling are realized. Two identical slots etched on the ground plane are utilized to excite the radiating patch with the reduced cross-polarization level. A short slot etched on the ground plane is employed for cross-coupling, which introduces two controllable radiation nulls with a steep roll-off rate. In addition, owing to the split-ring resonators and hairpin resonators, the improved impedance bandwidth is achieved with the fourth-order filtering response. To demonstrate the proposed design techniques, both the filtering antenna element and the low-sidelobe array are designed, fabricated, and measured. The measured results show that the proposed antenna has the impedance bandwidth of 12% (4.78–5.39 GHz) with the total height of 0.06?0 , the cross-polarization level lower than ?31 dB, and two radiation nulls with the suppression higher than 31 dB. For the low-sidelobe antenna array, wide impedance bandwidth is also obtained with the sidelobe level below ?28.7 dB, the cross-polarization level below ?34 dB, and the out-of-band suppression better than 25 dB

Disclination and molecular director studies on bowlic columnar nematic phase using mosaic-like morphology decoration method

National Natural Science Foundation of China [20774077]; Natural Science Foundation of Fujian, China [E0510003, E0710025]; Project of Science and Technology of Xiamen, China [3502Z20055013]Two bowlic cyclotriveratrylene CTV-1 and CTV-2, with different peripheral groups of -OCH(3) and -OCH(2)CH(3) for CTV-1 and -OCH(3) and -OCH(2)COOCH(3) for CTV-2, respectively, were synthesized by typical trimerization via a multistep sequence from vanillin. Both bowlic CTV molecules were thermotropic liquid crystals, and presented typical grainy textures of the nematic phase and homogeneous texture of the single domain nematic phase. It is of interest to observe the regular and beautiful mosaic-like morphologies after cooling from liquid crystalline phases, which appeared and vanished repeatedly in several circles of cooling and heating. The size of each mosaic was several dozens of micron. In nature, the mosaic-like morphologies are the optical pattern of cracks formed by the shrinking, due to the crystallization of frozen texture of nematic phases. By means of scanning electron microscopy, the mosaic-like morphologies were observed to consist of lamellae, and each mosaic is a rectangular multi-layer lamella, which is composed of packed single-layered lamellae. The fibrils in the diameter of about 1 mu m were observed, which are the structural units of lamellae and would be the bundles of the bowlic molecular columns. The mosaic-like morphologies decorate the bowlic molecular columnar nematic phase, therefore, a novel mosaic-like morphologies decoration method was applied to reveal the director distribution of several kinds of point disclinations, such as s = +1(delta=0A degrees and delta =90 A degrees) and s = +/- 1/2, and NSel domain walls. It was shown that the bowlic molecular columnar nematic phase behaved as normal nematic phases; however, the basic structural units ordered were the bowlic molecular column or the bundles of bowlic molecular column (i.e. fibrils), but not the bowlic molecules themselves. The bowlic molecular columns acted as the rod-like molecules in a normal nematic phase. Therefore, a new term BCN (bowlic columnar nematic phase) is used to describe the anomalous nematic phase in this paper

Broadband Circularly Polarized Filtering Antennas

This paper consists of two parts. The first part presents a review of the recent development in broadband circularly polarized filtering antennas. The second part presents a novel design of broadband integrated filtering antenna based on eighth-mode SIW (EMSIW) resonators for rectenna applications. This work has three main novel contributions. First, by adjusting the external quality factors and coupling coefficients of the resonators in this filtering antenna, optimum input impedance with a complex value can be realized within the filtering antenna. Thus there is no need for an external impedance matching network, which is usually required between the antenna and the rectifying circuits; Second, compared with traditional microstrip resonators, high-Q EMSIW cavities are used to increase antenna gain; third, the coupling gap between the EMSIW resonators also acts as the feeding structure of the radiator. So the feeding structures are all on the middle layer. The ground plane on the back side is a complete structure without any defects. This novel structure design improves front-to-back ratio to enhance the antenna receiving efficiency. To validate this method, two C-band circularly polarized integrated filtering antennas with an input impedance of 50 $\Omega$ and complex impedance are designed, simulated, and fabricated. The measured results show that the operating frequency bandwidth of the proposed antennas is more than 14.5% at C-band with the gain above 8 dBi. The 3-dB axial ratio bandwidth is larger than 8.5% and the front-to-back ratio is higher than 18 dB. Moreover, the proposed antenna with complex impedance is conjugate matched with the input impedance of a specific rectifying circuit at 5.8 GHz and harmonics suppression at the second-harmonic frequency is achieved

Transplacentally Acquired Maternal Antibody against Hepatitis B Surface Antigen in Infants and its Influence on the Response to Hepatitis B Vaccine

BACKGROUND: Passively acquired maternal antibodies in infants may inhibit active immune responses to vaccines. Whether maternal antibody against hepatitis B surface antigen (anti-HBs) in infants may influence the long-term immunogenicity of hepatitis B vaccine remains unknown. METHODOLOGY/PRINCIPAL FINDINGS: Totally 338 pairs of mothers and children were enrolled. All infants were routinely vaccinated against hepatitis B based on 0-, 1- and 6-month schedule. We characterized the transplacental transfer of maternal anti-HBs, and compared anti-HBs response in children of mothers with or without anti-HBs. In a prospective observation, all 63 anti-HBs positive mothers transferred anti-HBs to their infants; 84.1% of the infants had higher anti-HBs concentrations than their mothers. One and half years after vaccination with three doses of hepatitis B vaccine, the positive rate and geometric mean concentration (GMC) of anti-HBs in 32 infants with maternal anti-HBs were comparable with those in 32 infants without maternal antibody (90.6% vs 87.5%, P = 0.688, and 74.5 vs 73.5 mIU/ml, P = 0.742, respectively). In a retrospective analysis, five and half years after vaccination with three doses vaccine, the positive rates of anti-HBs in 88 children of mothers with anti-HBs ≥1000 mIU/ml, 94 children of mothers with anti-HBs 10-999 mIU/ml, and 61 children of mothers with anti-HBs <10 mIU/ml were 72.7%, 69.2%, and 63.9% (P = 0.521), respectively; anti-HBs GMC in these three groups were 38.9, 43.9, and 31.7 mIU/ml (P = 0.726), respectively. CONCLUSIONS/SIGNIFICANCE: The data demonstrate that maternal anti-HBs in infants, even at high concentrations, does not inhibit the long-term immunogenicity of hepatitis B vaccine. Thus, current hepatitis B vaccination schedule for infants will be still effective in the future when most infants are positive for maternal anti-HBs due to the massive vaccination against hepatitis B

Dynamic traffic signal control using mean field multi‐agent reinforcement learning in large scale road‐networks

Abstract Multi‐agent reinforcement learning has played an increasingly important role in intelligent traffic signal control due to its self‐learning ability. However, existing algorithms only focus on signal timing mechanism design while ignoring the exponential growth of the joint action dimension as the number of intersections increases, which will ultimately face the learning difficulty. In this paper, traditional traffic methods are introduced into MARL to flexibly determine the phase and duration of each intersection. The proposed MARL algorithm based on mean field theory has the ability to convert a large number of agents to approximately binary interaction, which can effectively reduce the dimension of joint action space in multi‐agent environment and learn in a robust process. Besides, to improve the performance of traditional traffic methods, the recurrent neural network (RNN) and an improved Webster's formula with revised parameters are combined to dynamically determine the phase duration according to the historical volume of traffic flow. The simulation results indicate that the proposed algorithm shows superior scalability compared to baseline methods and has great potential to be applied in the large scale road‐networks scenario

The combined effects of overweight/obesity and dietary antioxidant quality score on hypertension in children and adolescents

Abstract Background This study was to evaluate the combined effects of overweight/obesity and DAQS on the risk of hypertension in children and adolescents. Methods In this cross-sectional study, the data of 14,316 subjects were extracted from the National Health and Nutrition Examination Survey (NHANES). Multivariate logistic regression analysis was used to explore the associations of obesity and DAQS with the risk of hypertension. The combined effect of overweight/obesity and DAQS on the risk of hypertension was evaluated. Results Body mass index (BMI)-for-age  0.05). Subjects with BMI-for-age of < 85th percentile and DAQS < 3 was associated with decreased risk of hypertension (OR = 0.53, 95%CI: 0.35–0.79). People with BMI-for-age of < 85th percentile and DAQS ≥ 3 was correlated with decreased risk of hypertension (OR = 0.52, 95%CI: 0.36–0.74). Subgroup analysis revealed that in subjects aged ≥ 12 years, decreased risk of hypertension was observed in BMI-for-age < 85th percentile and DAQS < 3 group (OR = 0.48, 95%CI: 0.31–0.73) as well as BMI-for-age < 85th percentile and DAQS ≥ 3 group (OR = 0.47, 95%CI: 0.32–0.67). In boys, BMI-for-age < 85th percentile and DAQS < 3 group (OR = 0.45, 95%CI: 0.25–0.81) as well as BMI-for-age < 85th percentile and DAQS ≥ 3 group (OR = 0.40, 95%CI: 0.25–0.65) were correlated with decreased risk of hypertension. Conclusion Overweight/obesity and DAQS had combined effects on the risk of hypertension in children and adolescents, which implied that for children and adolescents with normal weight, to keep normal weight combined with high quality of diet might be recommended