Circularly polarized integrated filtering antenna with polarization reconfigurability

A new design of circularly polarized (CP) integrated filtering antennas with reconfigurable polarization is proposed in this paper. Two phase-reconfigurable coupled λ/2-resonator pairs have been used to feed the antenna and generate the 2nd-order filtering response and the circular polarization simultaneously. By switching the PIN diodes inserted in the feeding network, a phase difference of +90° or - 90° can be realized at the outputs of the feeding network. This renders the antenna’s capability of switching its polarization from right hand circular polarization (RHCP) to left hand circular polarization (LHCP) or vice versa. The use of the coupled-resonator pairs significantly improves the frequency selectivity and out-of-band rejection of the CP antenna. To the best of the authors’ knowledge, this is the first report of a multifunctional antenna which has integrated filtering performance, circular polarization and polarization reconfigurability. To verify the design concept, a reconfigurable CP antenna operating at 2.45 GHz is implemented. The simulated and measured results agree well with each other and show that the antenna has an impedance bandwidth of 4.5 %, an average in-band gain of 6.0 dBic (LHCP)/6.1 dBic (RHCP), out-of-band rejections of greater than 10.8 dB, and 3-dB AR bandwidth of 9.4 %/10.5 %

Confined granular packings: structure, stress, and forces

The structure and stresses of static granular packs in cylindrical containers are studied using large-scale discrete element molecular dynamics simulations in three dimensions. We generate packings by both pouring and sedimentation and examine how the final state depends on the method of construction. The vertical stress becomes depth-independent for deep piles and we compare these stress depth-profiles to the classical Janssen theory. The majority of the tangential forces for particle-wall contacts are found to be close to the Coulomb failure criterion, in agreement with the theory of Janssen, while particle-particle contacts in the bulk are far from the Coulomb criterion. In addition, we show that a linear hydrostatic-like region at the top of the packings unexplained by the Janssen theory arises because most of the particle-wall tangential forces in this region are far from the Coulomb yield criterion. The distributions of particle-particle and particle-wall contact forces $P(f)$ exhibit exponential-like decay at large forces in agreement with previous studies.Comment: 11 pages, 11 figures, submitted to PRE (v2) added new references, fixed typo

Specific dose-dependent effects of ethane 1,2-dimethanesulfonate in rat and mouse Leydig cells and non-steroidogenic cells on programmed cell death

The mechanism by which ethane 1,2-dimethanesulfonate (EDS) selectively kills Leydig cells is poorly understood. To characterize further the cell-specific actions of EDS, we studied biochemical and morphological changes during apoptosis in different Leydig cell and non-steroidogenic cell models.Rat testicular and H540 tumor Leydig cells were killed by 1-2 mM EDS, whereas 20 mM EDS were required for MA-10 cells. This higher concentration of EDS was also necessary for activation of apoptosis in non-steroidogenic Chinese hamster ovary cells, whereas COS-1 monkey kidney cells were resistant. These variable effects of EDS on apoptosis were independent of new protein synthesis and, interestingly, could be delayed by co-incubation with dibutyrl cyclic AMP. Along with cell death, we also observed chromosomal fragmentation and other hallmarks indicative of apoptosis as evidenced by DNA laddering and fluorescent microscopy. Time-lapse photography with a confocal microscope showed that the time of onset, duration and even the sequence of apoptotic events between individual H540 cells was heterogeneous. When the dose of EDS was gradually increased from 2 to 10 mM, the proportion of cells showing normal apoptotic features gradually decreased. Intriguingly, treatment with 10 mM EDS did not result in death for most cells and was marked by an absence of DNA laddering and ultrastructural features of apoptosis and necrosis. However, incubation with 20 mM EDS resulted in necrosis.These results demonstrated that the effects of EDS on cell survival are not specific to Leydig cells, that different cell types have different sensitivities to EDS and that stimulation of the cAMP pathway may mitigate EDS action. The data obtained with H540 cells further revealed that EDS can induce two types of programmed cell death

An evaluation of peptone products and fish meal on nursery pig performance

A total of 360 nursery pigs (PIC C327 × 1050, initially 11.8 lb and 21 d of age) were used in a 35-d study to evaluate the effects of select menhaden fish meal (SMFM), PEP2+ (also known as Ferm O Tide), Peptone 50, and PEP-NS on nursery pig performance. PEP2+, Peptone 50, and PEP-NS are all porcine intestinal mucosa products, but differ based on the carriers with which they are co-dried. PEP2+ is co-dried with enzymatically processed vegetable proteins. Peptone 50 is co-dried with a vegetable protein, while PEP-NS uses by-products from corn wet-milling. Phase 1 diets were fed in pellet form from d 0 to 8. Phase 2 diets were fed in meal form from d 8 to 21. A common corn-soybean meal diet was fed from d 21 to 35. There were 6 dietary treatments: (1) a negative control diet containing 2.5% spray-dried animal plasma (SDAP) in Phase 1 followed by no specialty protein sources in Phase 2; (2) a diet containing 5% SDAP in Phase 1 and 3% SMFM in Phase 2; (3) a blend of 5% SDAP and 3% SMFM during Phase 1 and 6% SMFM during Phase 2; (4) a blend of 5% SDAP and 3% PEP2+ during Phase 1 and 6% PEP2 during Phase 2; (5) a blend of 5% SDAP and 3% PEP 50 during Phase 1 and 6% PEP50 during Phase 2, and (6) a blend of 5% SDAP and 3% PEP-NS during Phase 1 and 6% PEP-NS during Phase 2. During Phase 1, there were no differences in F/G among pigs fed any of the dietary treatments. During Phase 2 (d 8 to 21), pigs fed 6% PEP2+ had greater (P < 0.05) ADG compared to those fed the negative control diet, 3% or 6% fish meal, with pigs fed PEP50 and PEP NS intermediate. Furthermore, pigs fed 6% PEP2+ had the greatest improvement (P < 0.02) in F/G compared to pigs fed all other experimental diets. Overall, pigs fed diets containing PEP2+ had increased (P < 0.03) ADG and ADFI compared to pigs fed the negative control diet. Pigs fed 3% PEP2+ during Phase 1 and 6% PEP2+ during Phase 2 had greater (P < 0.05) ADFI compared to those fed 3% SMFM during Phase 1 and 6% SMFM during Phase 2. In conclusion, PEP2+, Peptone 50, and PEP-NS can be used as specialty protein sources to replace select menhaden fish meal in Phase 2 nursery pig diets. In addition pigs fed PEP2+ had greater ADG than those fed fish meal

Smallholder dairy technology in coastal Kenya. An adoption and impact study

This study examines the factors influencing adoption of three related dairy technologies in coastal Kenya, and assesse the impacts of dairy adoption on household income, employment generation and nutritional status of pre-school children. The technologies studied were adoption of grade and crossbred dairy animals, planting of the fodder Napier grass and use of the infection and treatment method of immunisation against East Coast fever. A series of household surveys was conducted from mid 1997 to mid 1998. The descriptive results from surveys of 202 households in Coast Province indicate that adoption of a grade or crossbred dairy animal may result in substantial increases in household income, can generate paid (secondary) employment, and may improve the nutritional status of pre-school-age children in the household. Econometric analyses, which controlled for numerous confounding factors, provided less consistent support for the impact of adoption on household income and paid employment. It appears that neither the adoption nor productivity of dairying are constrained by poor availability of technology options. For dairy development activities on the coast, two areas merit attention: mechanisms for easing access to grade and crossbred dairy cattle, either through credit schemes or through self-help smallholder co-operatives, and reducing the disease risks associated with grade and crossbred dairy animals

Somatostatin receptor subtypes in human thymoma and inhibition of cell proliferation by octreotide in vitro

Somatostatin (SS) and SS receptor (SSR) subtypes, code-named sst1-5, are heterogeneously expressed in the normal human thymus. This suggests their involvement in controlling the immune and/or neuroendocrine functions in this organ. Moreover, recently a high in vivo uptake of [111In-DTPA-D-Phe1]octreotide has been reporte