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/

Identification of Nitric Oxide Responsive Genes in the Rudimentary Leaves of Litchi chinensis

Litchi (Litchi chinensis Sonn.) is an evergreen woody fruit tree widely cultivated in subtropical and tropical regions. Warm winter and hot spring often leads to abnormal floral differentiation in litchi. Under this condition, the rudimentary leaves in the floral buds expand and the inflorescences will stop developing. Thus, how to promote abortion of rudimentary leaves in litchi inflorescence are important for floral development. Previous study indicated that nitric oxide (NO) produced by sodium nitroprusside (SNP) promoted flowering and abortion of rudimentary leaves in litchi. In the present study, a suppression subtractive hybridization (SSH) was used to identify NO responsive genes. As a result, 16 high homologous ESTs were obtained from the SSH library of the SNP treated rudimentary leaves. The ESTs were classified into three groups. They are disease/defensive, protein destination and storage, and protein synthesis. Quantitative reverse transcription PCR (qRT-PCR) analysis indicated that 6 out of the 7 randomly selected ESTs’expression showed an increasing trend from 0 h to 10 h of SNP treatment. It is suggested that the litchi homologs 18S ribosomal RNA gene, cytochrome P450 like TBP, and the senescence-associated protein, chaperone protein, and a hypothetical protein encoding genes may be involved in the NO-induced senescence in litchi rudimentary leaves. LcERD15-like may be a key gene involved in this process

Effects of cytokinin and abscisic acid on heat resistance of Vetiveria zizanioides

Vetiveria zizanioides is ideal in maintaining soil and water, and is widely used for remediation of soil contaminated by heavy metals. However, it is affected by high-temperature stress. In this study, Vetiveria zizanioides plants were sprayed with 6-BA and ABA in a growth chamber 1 d before heat stress treatment, then the plants were subjected to high-temperature conditions. Relative water content, relative electrical conductivity, contents of ascorbic acid (AsA) and reduced glutathione (GSH) as the antioxidative substances, and content of malondiadehyde (MDA) were determined. Also, the antioxidative enzyme activities and the osmoprotectants levels were detected. Diaminobenzidine (DAB) staining of leaves and roots in Vetiveria zizanioides was observed for determination of hydrogen peroxide accumulation. The results showed that relative water content was decreased, relative electrical conductivity and MDA content were increased by the heat stress treatment. Under high-temperature conditions, relative water content was increased and relative electrical conductivity was decreased by 6-BA and ABA treatments. At the middle and the late stages of the heat stress treatment, activities of superoxide dismutase (SOD), peroxidase (POD) and catalase (CAT), and the contents of ASA and GSH in leaves of the 6-BA-treated and ABA-treated plants were significantly higher, whereas the MDA content was significantly lower than those in the high-temperature controls. Hydrogen peroxide accumulation levels in the 6-BA-treated and ABA-treated leaves and roots were lower than in the high-temperature controls. Contents of soluble sugar, sucrose, and glucose in the 6-BA-treated and ABA-treated leaves were significantly higher than those in the high-temperature controls. Proline content in the 6-BA-treated and ABA-treated leaves was stable. The results suggested that the enhancement of the heat resistance by 6-BA and ABA treatments was correlated with the activation of the antioxidant system, as well as the sugar-based osmoprotectant

Effects of Shading on Carbohydrates of Syzygium samarangense

Wax apple (Syzygium samarangense) is an important tropical fruit tree cultivated in Southeast Asian. It produces red pear-like shape fruits. The fruit flesh is considered high in antioxidants, phenolics, and flavonoids that have a potential to contribute to the human healthy diet, and was proved to have anti-inflammatory and antimicrobial characteristics. To allow year-round marketing of high quality wax apple fruit, growers always perform shading to inhibit new flushes so as to repress vegetative growth and promote reproductive growth. To investigate the effect of shading on carbohydrates, wax apple trees were shaded with sun shade nets under field conditions. The effects of shading on shoot growth were studied and leaf carbohydrate levels of the trees were determined. The results showed that shading inhibit the the growth of the terminal shoots and promoted bud dormancy. Shading also reduced total soluble sugar, sucrose, glucose, fructose, and starch levels of leaves. The results suggested that shading reduced carbohydrate accumulation and repressed vegetative growth

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