Dye-sensitised Solar Cell Antenna

Dye-sensitised solar cells are proposed as a solarantenna in the form of a proof-of-concept dipole operating at 1.1 GHz. Comprised of glass plates in basic rectangular shapes, various material properties are considered for impact on antenna performance at three phases of assembly. Simulated and empirical analyses indicate how such low-cost solar cells can also realise viable concurrent antenna designs

Integration of Antenna Array with Multicrystalline Silicon Solar Cell

The integration of a low-profile antenna array with a multicrystalline silicon solar cell capable of powering a low-power wireless sensor at 2.45 GHz is reported. Lattice bus bars on the cell are exploited to minimize antenna shadows from low-profile antennas and transmission lines for a higher output power. The dual inverted-F array improves gain, and beam switching enables the array to sweep a wider coverage angle with larger beamwidths compared to other solar integrated antennas

The VLT-FLAMES Tarantula Survey

We present a number of notable results from the VLT-FLAMES Tarantula Survey (VFTS), an ESO Large Program during which we obtained multi-epoch medium-resolution optical spectroscopy of a very large sample of over 800 massive stars in the 30 Doradus region of the Large Magellanic Cloud (LMC). This unprecedented data-set has enabled us to address some key questions regarding atmospheres and winds, as well as the evolution of (very) massive stars. Here we focus on O-type runaways, the width of the main sequence, and the mass-loss rates for (very) massive stars. We also provide indications for the presence of a top-heavy initial mass function (IMF) in 30 Dor.Comment: 7 Figures, 8 pages. Invited talk: IAUS 329: "The Lives and Death-Throes of Massive Stars

Amorphous Silicon Solar Vivaldi Antenna

An ultra-wideband solar Vivaldi antenna is proposed. Cut from amorphous silicon cells, it maintains a peak power at 4.25 V which overcomes a need for lossy power management components. The wireless communications device can yield solar energy or function as a rectenna for dual-source energy harvesting. The solar Vivaldi performs with 0.5 - 2.8 dBi gain from 0.95 - 2.45 GHz and in rectenna mode, it covers three bands for wireless energy scavenging

Effect of restricted access time to pasture on dairy cow milk production, grazing behavior, and dry matter intake

The objective of this experiment was to investigate the effect of restricting pasture access time on milk production and composition, body weight and body condition score change, dry matter intake, and grazing behavior of autumn calving dairy cows in midlactation. Fifty-two (19 primiparous and 33 multiparous) Holstein-Friesian dairy cows (mean calving date, August 17 ± 91.2 d) were randomly assigned to a 4-treatment (n = 13) randomized block design grazing study. The 4 grazing treatments were: (i) full-time access to pasture (22H; control), (ii) 9-h access to pasture (9H), (iii) two 4.5-h periods of access to pasture after both milkings (2 × 4.5H), and (iv) two 3-h periods of access to pasture after both milkings (2 × 3H). Experimental treatments were imposed from March 7 to April 6, 2007 (31 d). The pregrazing herbage mass of swards offered to all treatments was 1,268 kg of dry matter/ha, and sward organic matter digestibility was 86.4%, indicating high-quality swards conducive to high dry matter intake. Swards where animals had 22H and 2 × 4.5H access to pasture had the lowest postgrazing sward heights (3.5 cm), reflecting the greatest levels of sward utilization. After the experimental period, there were no differences in milk production; however, the 2 × 3H animals tended to have lower milk protein concentration (−0.17%) compared with 22H animals. Furthermore, dry matter intake of the 9H animals was lower than 22H animals. Although restricting access time to pasture decreased grazing time, animals compensated by increasing their intake/minute and intake/bite. Restricting pasture access time resulted in much greater grazing efficiency, because the 9H, 2 × 4.5H, and 2 × 3H treatments spent a greater proportion of their time at pasture grazing (81, 81, and 96%, respectively) than 22H animals (42%). Results of this study indicate that allocating animals restricted access to pasture does not significantly affect milk production. This study also found that the total access time should be greater than 6 h and that perhaps needs to be divided into 2 periods

Interpersonal problems across restrictive and binge-purge samples: Data from a community-based eating disorders clinic

Contemporary models of eating disorders suggest that interpersonal problems contribute to the maintenance of eating disorders. This study examined whether baseline interpersonal problems differed across eating disorder diagnoses and across eating disorder subtypes (“restrictors” vs. “binge-purge” patients) in a large clinical sample. Patients with a primary eating disorder diagnosis (N = 406) completed measures of interpersonal problems, eating disorder symptoms, and mood prior to treatment at a specialist eating disorder clinic. Across the sample, more severe eating disorder psychopathology was associated with significantly greater difficulty socializing. Anorexia Nervosa (AN) / restrictor patients reported significantly greater difficulty socializing than Bulimia Nervosa (BN) / binge-purge patients. AN patients reported significantly greater difficulty on a measure of competitiveness/assertiveness compared to BN and Eating Disorder Not Otherwise Specified patients. All findings were significant after controlling for comorbid depression and anxiety symptoms. Interpersonal problems appear to be unique risk factors for eating disorders. Specific interpersonal mechanisms include difficulties socializing and being assertive, which were most pronounced in AN patients. These findings provide potential avenues for enhancing interventions, such as adjunctive assertiveness training for AN