A novel low profile dual band patch antenna is presented. It consists of a composite right/left-handed transmission line (CRLH TL) unit cell gap coupled with the radiating edge of a rectangular patch antenna. The dual band behavior is achieved by coupling the zeroth order resonance mode of CRLH TL and TM10 mode of the patch antenna. It is shown that frequency ratio can be changed by varying the gap between the patch and CRLH TL unit cell. The proposed configuration enables frequency reconfigurability by changing the CRLH TL unit cell using a switch. A prototype of the antenna having frequency ratio f2/f1 = 1.08 is designed and fabricated. The proposed antenna shows measured S11 ≤ −10 dB bandwidth of 100 and 50 MHz at resonance frequencies of f1 = 4.84 and f2 = 5.22 GHz, respectively. A 2 × 2 dual band CRLH TL coupled patch array is also presented, showing more than 12.7 dBi gain at both resonance frequencies.

We computationally investigate coupling of a nonlinear rotational dissipative element to a sprung circular cylinder allowed to undergo transverse vortex-induced vibration (VIV) in an incompressible flow. The dissipative element is a‘nonlinear energy sink’ (NES), consisting of a mass rotating at fixed radius about the cylinder axis and a linear viscous damper that dissipates energy from the motion of the rotating mass. We consider the Reynolds number range $20\leqslant Re\leqslant 120$ , with $Re$ based on cylinder diameter and free-stream velocity, and the cylinder restricted to rectilinear motion transverse to the mean flow. Interaction of this NES with the flow is mediated by the cylinder, whose rectilinear motion is mechanically linked to rotational motion of the NES mass through nonlinear inertial coupling. The rotational NES provides significant ‘passive’ suppression of VIV. Beyond suppression however, the rotational NES gives rise to a range of qualitatively new behaviours not found in transverse VIV of a sprung cylinder without an NES, or one with a ‘rectilinear NES’, considered previously. Specifically, the NES can either stabilize or destabilize the steady, symmetric, motionless-cylinder solution and can induce conditions under which suppression of VIV (and concomitant reduction in lift and drag) is accompanied by a greatly elongated region of attached vorticity in the wake, as well as conditions in which the cylinder motion and flow are temporally chaotic at relatively low $Re$ .

Model scale tests of modern ‘open rotor’ propulsor concepts that have potential for significant fuel burn reduction for aircraft applications were completed at NASA Glenn Research Center. The recent test campaign was a collaboration between NASA, FAA, and General Electric (GE). GE was the primary industrial partner, but other organisations were involved such as Boeing and Airbus who provided additional hardware for fuselage simulations. The open rotor is a modern version of the UnDucted Fan (UDF®) that was flight tested in the late 1980s through a partnership between NASA and GE. The UDF® was memorable for its scimitar shaped propeller blades and its unique noise signature. Design methods of the time were not able to optimise for both high aerodynamic efficiency and low noise simultaneously. Contemporary CFD/CAA based design methods can produce open rotor blade designs that maintain efficiency with acceptable acoustic signatures. Tests of two generations of new open rotor designs were conducted in the 9’ × 15’ Low Speed Wind Tunnel and the 8’ × 6’ Supersonic Wind Tunnel starting in late 2009 and completed in early 2012. Aerodynamic performance and acoustic data were obtained for take-off, approach and cruise conditions in isolated and semi-installed configurations. Additional detailed flow diagnostic measurements and acoustic measurements, including canonical shielding configurations, were obtained by NASA. NASA and GE conducted joint systems analysis to evaluate the performance of the new blade designs on a Boeing 737 class aircraft. The program demonstrated a 2-3% improvement in overall net efficiency relative to the best efficiency designs of the 1980s while nominally achieving 15-17 EPNdB noise margin to Chapter 4 (at a Technology Readiness Level of 5) for a notional aircraft system defined by NASA.

Necrotic enteritis (NE) caused by Clostridium spp. is an economically significant bacterial disease of poultry worldwide. Traditionally the disease has been prevented through feed supplementation with antibiotics sub-therapeutically as antimicrobial growth promoters (AGPs). However this practice has led to the emergence of resistant pathogenic microbes and drug residues, potentially threatening animal and public health. Therefore the marketing and incorporation of AGPs into poultry feed has been banned in Europe which has exacerbated the incidence of NE, bringing about huge economic losses to poultry farmers. Poultry researchers, exporters and consumers have emphasised AGP-free poultry rearing and have been searching for non-antibiotic and cost effective alternatives to control NE. Strategies suggested include vaccination, coccidiosis control, probiotics, competitive exclusion products, prebiotics, egg yolk immunoglobulins, bacteriophages (or phage gene products), organic acids, feed enzymes, plants and plants extracts/essential oils and nutritional changes.

There are many predisposing as well as virulence factors for NE induction and pathogenesis and more are expected to be discovered in the future. The ambiguous pathogenesis trend of the disease is still hindering the development of a potent active vaccine against NE. The choice of a single and fully effective approach is difficult. However, probiotics and specific egg yolk immunoglobulins (IgYs) alone or in combination could serve as promising strategies for controlling NE in broilers in the absence of AGPs.

A previously undescribed entomopoxvirus was isolated from larvae of Choristoneura conflictana Wlk. Samples of larvae taken from several points in Ontario indicated that the virus was widespread in the Province.

The morphology of the virus is described. The inclusion bodies are larger than those of another entomopoxvirus originally isolated from Choristoneura biennis Free. and propogated in Choristoneura fumiferana (Clem.). The virions are of the same order of size for both viruses. Microspindles are associated with these viruses and some of the spindles are occluded along with the virions within the oval inclusion bodies. The C. conflictana entomopoxvirus is also infectious to C. fumiferana.

From wings of flies to plant leafs, hydrophobic surfaces are well-common in nature. Many of these surfaces have micro and nano hierarchical structures coated with low surface energy layer. In this work, we mimicked similar structure by fabricating Teflon coated periodic and well-ordered silver nanorod arrays and investigated the effect of nanorod separation on water contact angle (WCA). The silver nanorod arrays were deposited on patterned and flat silicon substrates using glancing angle deposition (GLAD) technique. Then a thin layer of Teflon was deposited on the silver nanorods by small angle deposition (SAD) technique. A systematic increase in water contact angle was observed with increasing nanorod separation which is attributed to the decreased area fraction of solid-liquid interface.

Ensuring the delivery of comprehensive, high quality programs and services to seniors in Canada over the coming decades presents a significant challenge to policy makers and health care professionals. The goal of this study was to provide decision-makers with data on recent trends in the utilization of health services by seniors in Alberta. We compared recent trends in the utilization of acute hospital services (1992/93–1997/98), home care services (1994/95–1997/98), claims for physician consultations and procedures (1995/96–1997/98) and long-term facility care (1990–1996) for Albertans less than and over 65 years of age. We also assessed trends in the use of prescription drugs (1992/93–1997–98) by Albertans 65 years and older. Data for these analyses were obtained from Alberta Health and Wellness administrative databases and reports. Overall, the trends indicate fewer, though sicker, patients being cared for in institutions and more patients being cared for in the community. The receipt of prescription drugs obtained outside of facilities has also increased among seniors in recent years. The extent and appropriateness of substitution of community care for institutional care, the quality of that care, and whether health outcomes are better, worse, or unchanged, are important subjects for further study.

The 1,080 km2 Batang Gadis National Park in the North Sumatra province of Indonesia was established in December 2004 by the regional government of Mandailing Natal district. The Park has the potential to make an important contribution to tiger conservation but lacks scientific data on the occurrence of the species. This study aimed to assess the tiger population of the Park, using camera trapping conducted between December 2005 and July 2006. We recorded a mean tiger density of 1.8 tigers per 100 km2 (95% CI 1.8–6.4) and, based on this, estimated the tiger population in and adjacent to the Park to be 29–103 adults. We found that tiger presence was negatively correlated with altitude and positively correlated with distance from forest edge to the interior, and < 18% of the total suitable habitat occupied by tigers was of high quality. This study indicates that Batang Gadis National Park potentially serves as a natural corridor betwen the Angkola and Barumun-Rokan ecosystems, areas totalling c. 6,500 km2, and that this landscape could serve as a stronghold for tiger populations in northern Sumatra.

Self-assembled InGaAs quantum dots (QD) grown by metal organic chemical vapor deposition (MOCVD) have a natural peak emission wavelength around 1150-1200-nm due to its specific composition, shapes, and sizes. In this work, a new method to engineer the emission wavelength capability of MOCVD-grown InGaAs QD on GaAs to ∼1000-nm by utilizing interdiffused InGaAsP QD has been demonstrated. Incorporation of phosphorus species from the GaAsP barriers into the MOCVD-grown self-assembled InGaAs QD is achieved by interdiffusion process. Reasonably low threshold characteristics of ∼ 200-280 A/cm2 have been obtained for interdiffused InGaAsP QD lasers emitting at 1040-nm, which corresponds to blue-shift of ∼ 85-90-nm in comparison to that of unannealed InGaAs QD laser.

In this paper we report the effect of low temperature annealing on the high field magnetotransport properties of epitaxial thin films of (Ga, Mn)As Dilute Magnetic Semiconductor (DMS) with low concentration (1.5 %) of Mn doping, which results in a ferromagnetic insulator. Annealing at an optimal temperature enhances the conductivity, carrier concentration, and ferromagnetic transition temperature. The field dependence of magnetoresistance is different below and above the ferromagnetic transition temperature. An attempt is made to analyze the data using a theoretical model proposed by Kaminski and Das Sarma [1].