Adaptive wire bow-tie antenna for GPR applications

In this paper, the basic design of an adaptive ground penetrating radar antenna is introduced. The antenna is able to adapt its input impedance to a variation in the antenna elevation and soil type to keep reflections at the antenna's terminal minimum. As a result, energy transfer from the generator to the antenna is maximized, which in turn maximizes the energy radiated by the antenna into the ground for different antenna elevations and soil types. The antenna is based on a wire bow-tie structure with variable flare angle for adjusting the antenna's input impedance. The flare angle variation is realized by short-circuiting the gaps separating the wires from the feed point of the antenna, for which electronic switching devices such as PIN diodes could be used to allow fast and convenient control of the antenna's flare angle.     

China Cuts Tariffs to Fulfill WTO Commitments

<正> China further adjusts the tariffs from January1st,2010,mainly related to the MFN(most-favored nation) tax rate,annual provisionaltax rates,the agreement rates,preferentialtax rates and tariff lines.After thisadjustment,China's WTO tariff reductioncommitment has been fully completed.The average import tariff in 2010 is thesame as in 2009,remaining 9.8%.Amongthem,the average tax rate is set at 15.2% foragricultural products,and 8.9% for indus-     

Trade Surplus Shrank in August

<正> China's trade surplus narrowed 30.4% toUS$20.03 billion in August from July'sUS$28.73 billion,according to the reportreleased by the General Administration of Customs of China on September 10th.Exports rose 34.4% year-on-year to     

Effect of GABA,a Bacterial Metabolite,on Pseudomonas fluorescens Surface Properties and Cytotoxicity

Different bacterial species and, particularly Pseudomonas fluorescens, can produce gamma-aminobutyric acid (GABA) and express GABA-binding proteins. In this study, we investigated the effect of GABA on the virulence and biofilm formation activity of different strains of P. fluorescens. Exposure of a psychotropic strain of P. fluorescens (MF37) to GABA (10⁻⁵ M) increased its necrotic-like activity on eukaryotic (glial) cells, but reduced its apoptotic effect. Conversely, muscimol and bicuculline, the selective agonist and antagonist of eukaryote GABA_A receptors, respectively, were ineffective. P. fluorescens MF37 did not produce biosurfactants, and its caseinase, esterase, amylase, hemolytic activity or pyoverdine productions were unchanged. In contrast, the effect of GABA was associated to rearrangements of the lipopolysaccharide (LPS) structure, particularly in the lipid A region. The surface hydrophobicity of MF37 was marginally modified, and GABA reduced its biofilm formation activity on PVC, but not on glass, although the initial adhesion was increased. Five other P. fluorescens strains were studied, and only one, MFP05, a strain isolated from human skin, showed structural differences of biofilm maturation after exposure to GABA. These results reveal that GABA can regulate the LPS structure and cytotoxicity of P. fluorescens, but that this property is specific to some strains.     

Enhancing marital enrichment through spirituality: Efficacy data for prayer focused relationship enhancement.

We examined 393 African American married couples assigned to (a) a culturally sensitive version of a widely disseminated relationship enhancement program (CS-PREP); (b) a similar version of the same program that also included a focus on prayer (PFP condition); or (c) an information-only control condition in which couples received a self-help version of the same program. Husbands averaged 40.5 years of age and wives averaged 38.9 years. We found a significant interaction between intervention and time of assessment, reflecting group differences in linear trends for the three conditions, with the two intervention conditions performing better than the control condition, and PFP producing superior outcomes to CS-PREP only for wives at post and marginally better results at 12-month follow-up. Results support continued exploration of the adjunctive use of prayer in the context of relationship enhancement programs where appropriate to make them more culturally sensitive. (PsycINFO Database Record (c) 2011 APA, all rights reserved)     

Dielectric and impedance study of lead-free ceramic: (Na<Subscript>0.5</Subscript>Bi<Subscript>0.5</Subscript>)ZrO<Subscript>3</Subscript>

Polycrystalline sample of (Na_0.5Bi_0.5)ZrO₃ was prepared using a high-temperature solid-state reaction technique. XRD analysis indicated the formation of a single-phase orthorhombic structure. Dielectric study revealed the diffuse phase transition at 425 °C. AC impedance plots were used as tools to analyse the electrical behaviour of the sample as a function of frequency at different temperatures. The ac impedance studies revealed the presence of grain boundary effect at and above 350 °C. Complex impedance analysis indicated non-Debye type dielectric relaxation and negative temperature coefficient of resistance (NTCR) character of (Na_0.5Bi_0.5)ZrO₃. AC conductivity data were used to evaluate the density of states at Fermi level and activation energy of the compound. DC electrical and thermal conductivities of grain and grain boundary have been assessed.     

Nature and nurture, danger and delight: urban women's experiences of the natural world

In this paper, we address a research lacuna in the area of human experience of, and interaction with, nature. We focus on women in an urbanized setting, exploring their actual and desired experiences of the natural world, using Singapore as a case study. Our intention is to contribute to both the evolving theoretical and empirical discussions on this subject. Based on data collected from focus group discussions and household questionnaires, we conclude that women's relationships with nature in Singapore are underscored by a strong inclination towards nurturing: teaching, tending and caring, in a way that is not as apparent in men's relationships with nature. Women's relationships with nature may also be conceptualized in terms of 'danger' and 'delight', a fine balance between ambivalent experiences of fear and enjoyment. In comparing results based on the Singapore context with those in Britain, sources of enjoyment appear to be similar, but the different social situations have resulted in different sources of fear. We conclude by putting forward some recommendations for planning and designing green areas that may enhance women's use and enjoyment of nature areas.     

Active Targeting Using HER‐2‐Affibody‐Conjugated Nanoparticles Enabled Sensitive and Specific Imaging of Orthotopic HER‐2 Positive Ovarian Tumors

Despite advances in cancer diagnosis and treatment, ovarian cancer remains one of the most fatal cancer types. The development of targeted nanoparticle imaging probes and therapeutics offers promising approaches for early detection and effective treatment of ovarian cancer. In this study, HER‐2 targeted magnetic iron oxide nanoparticles (IONPs) are developed by conjugating a high affinity and small size HER‐2 affibody that is labeled with a unique near infrared dye (NIR‐830) to the nanoparticles. Using a clinically relevant orthotopic human ovarian tumor xenograft model, it is shown that HER‐2 targeted IONPs are selectively delivered into both primary and disseminated ovarian tumors, enabling non‐invasive optical and MR imaging of the tumors as small as 1 mm in the peritoneal cavity. It is determined that HER‐2 targeted delivery of the IONPs is essential for specific and sensitive imaging of the HER‐2 positive tumor since we are unable to detect the imaging signal in the tumors following systemic delivery of non‐targeted IONPs into the mice bearing HER‐2 positive SKOV3 tumors. Furthermore, imaging signals and the IONPs are not detected in HER‐2 low expressing OVCAR3 tumors after systemic delivery of HER‐2 targeted‐IONPs. Since HER‐2 is expressed in a high percentage of ovarian cancers, the HER‐2 targeted dual imaging modality IONPs have potential for the development of novel targeted imaging and therapeutic nanoparticles for ovarian cancer detection, targeted drug delivery, and image‐guided therapy and surgery.