Impact of the inherent periodic structure on the effective medium description of left-handed and related meta-materials

We study the frequency dependence of the effective electromagnetic parameters of left-handed and related meta-materials of the split ring resonator and wire type. We show that the reduced translational symmetry (periodic structure) inherent to these meta-materials influences their effective electromagnetic response. To anticipate this periodicity, we formulate a periodic effective medium model which enables us to distinguish the resonant behavior of electromagnetic parameters from effects of the periodicity of the structure. We use this model for the analysis of numerical data for the transmission and reflection of periodic arrays of split ring resonators, thin metallic wires, cut wires as well as the left-handed structures. The present method enables us to identify the origin of the previously observed resonance/anti-resonance coupling as well as the occurrence of negative imaginary parts in the effective permittivities and permeabilities of those materials. Our analysis shows that the periodicity of the structure can be neglected only for the wavelength of the electromagnetic wave larger than 30 space periods of the investigated structure.Comment: 23 pages, 14 figure

Spin relaxation in mesoscopic superconducting Al wires

We studied the diffusion and the relaxation of the polarized quasiparticle spins in superconductors. To that end, quasiparticles of polarized spins were injected through an interface of a mesoscopic superconducting Al wire in proximity contact with an overlaid ferromagnetic Co wire in the single-domain state. The superconductivity was observed to be suppressed near the spin-injecting interface, as evidenced by the occurrence of a finite voltage for a bias current below the onset of the superconducting transition. The spin diffusion length, estimated from finite voltages over a certain length of Al wire near the interface, was almost temperature independent in the temperature range sufficiently below the superconducting transition but grew as the transition temperature was approached. This temperature dependence suggests that the relaxation of the spin polarization in the superconducting state is governed by the condensation of quasiparticles to the paired state. The spin relaxation in the superconducting state turned out to be more effective than in the normal state.Comment: 9 pages, 8 figure

Gilt Training for Electronic Sow Feeding Systems in Gestation

An electronic sow feeding (ESF) system provides the capability of feeding group-housed gestating gilts and sows on an individual basis. One of the most critical and yet often neglected steps in making an ESF system a success is proper gilt training. Different farms have protocols adapted to their particular situation, but the overall goal of gilt training is to ensure that a high percentage of gilts learn how to utilize the ESF station before they are moved to gestation. There are three critical steps in proper gilt training. These include: 1) pre-training; 2) training once the gilts have been moved to the training pen with the ESF; and 3) a post-training period. To have a successful gilt training requires dedicated people who are patient, observant, and also who are able to establish a connection with the females. This frequently necessitates that one or two people are directly responsible for gilt training in an ESF system. This paper will illustrate some of the key gilt training steps involved with an ESF system

Effects of Standardized Ileal Digestible Lysine on Nursery Pig Growth Performance

Lysine is the first limiting amino acid in swine diets, thus providing the appropriate level in the diet is critical to growth performance. Therefore, the objective of this study was to determine the standardized ileal digestible (SID) Lys requirement of nursery pigs from 15 to 35 lb. A total of 300 maternal line barrows (200 × 400, DNA, Columbus, NE; initially 14.9 ± 0.5 lb BW) were fed six experimental diets as part of a 21-d trial. Pigs were randomly allotted to pens at weaning based on BW, and were fed a common pelleted diet for 9 d after weaning. Pens were then randomly assigned to dietary treatments (10 pens/treatment with 5 pigs/pen) based on average pig weight. The six dietary treatments had increasing SID Lys (1.05, 1.15, 1.25, 1.35, 1.45, and 1.55%) and were achieved by increasing the inclusion of crystalline AA, allowing soybean meal to stay constant across dietary treatments. Experimental data were analyzed using general linear and non-linear mixed models with heterogeneous residual variances. Competing models included linear (LM), quadratic polynomial (QP), broken-line linear (BLL), and broken-line quadratic (BLQ). For ADG, F/G, and IOFC, the best-fitting model was selected using Bayesian information criterion. Overall, increasing SID Lys improved (linear, P \u3c 0.05) ADG and F/G. There was also a tendency for a quadratic response for ADG (P \u3c 0.10) with increasing SID Lys. The ADFI increased (quadratic, P \u3c 0.05) from 1.05 to 1.25% SID Lys with little improvement thereafter. For ADG, the best-fitting comparable models were BLL and BLQ, in which the maximum mean ADG was estimated at 1.29% (95% CI: 1.23, 1.35%) and 1.47% (95% CI: 1.31, \u3e 1.55%) SID Lys, respectively. For F/G, the best-fitting model was the LM where F/G was improved up to at least 1.55% SID Lys. For income over feed cost (IOFC), the best-fitting model was the BLL, in which the maximum mean IOFC was estimated at 1.25% (95% CI: 1.14, 1.36%). In conclusion, the estimated SID Lys required for maximum mean ADG of these maternal line barrows was lower than the estimated mean SID Lys required for maximum mean F/G. This study provides evidence that different response variables can result in different estimates of the requirements; however, at least 1.25% SID Lys was needed to maximize IOFC

PLANAR ACCELERATOR STRUCTURES FOR MILLIMETER WAVELENGTHS �

y,R.H.SIEMANN y

Determining the standardized ileal digestible lysine requirement of 6.8 to 15.9 kg pigs

Citation: Vier, C. M., De Souza, I. B., De Jong, J. A., Goncalves, M. A. D., Jones, A. M., Goodband, R. D., . . . Dritz, S. S. (2016). Determining the standardized ileal digestible lysine requirement of 6.8 to 15.9 kg pigs. Journal of Animal Science, 94, 191-191. doi:10.2527/msasas2016-408A total of 300 maternal line barrows (DNA; 200 × 400, initially 6.75 ± 0.23 kg BW) were used in a 21d trial to determine the standardized ileal digestible (SID) Lys requirement of nursery pigs from 6.8 to 15.9 kg. Pigs were randomly allotted to pens at weaning based on BW and were fed a common diet for 9 d after weaning. There were 10 replicate pens/treatment and 5 pigs/pen. Pens of pigs were allotted to experimental diets based on average BW, in a completely randomized design. The 6 dietary treatments consisted of 1.05, 1.15, 1.25, 1.35, 1.45, and 1.55% SID Lys and were achieved by increasing the inclusion of crystalline amino acids, allowing soybean-meal to stay constant across dietary treatments. Experimental data was analyzed using general linear and nonlinear mixed models with heterogeneous residual variances and pen as the experimental unit. Competing models included linear (LM), quadratic polynomial (QP), broken-line linear (BLL), and broken-line quadratic (BLQ). The best-fitting model for each response was selected using Bayesian information criterion (BIC). Increasing SID Lys linearly improved (P = 0.001) G:F. There was a marginal quadratic response for ADG (P = 0.067) with increasing SID Lys. The ADFI increased in a quadratic manner (P = 0.019) from 1.05 to 1.25% SID Lys. For ADG, the best-fitting comparable models were BLL [predicted equation: 462– 271 × (1.29– Lys), if SID Lys 1.55]%), respectively. For G:F, the best-fitting models were QP [predicted equation: 0.750– 0.317 × (Lys) + 0.214 × (Lys)2] and LM [predicted equation: 0.392 + 0.241 × (Lys)], estimating the requirement at greater than 1.55% for both models. In conclusion, the estimated mean SID Lys required for nursery pigs from 6.8 to 15.9 kg ranged from 1.29% for maximum ADG to at least 1.55% for maximum G:F

Standardized Total Tract Digestible Phosphorus Requirement of 25- to 50-lb Pigs Fed Diets Containing Phytase

A total of 2,140 barrows and gilts (PIC 337 × Camborough) with an initial pen average body weight (BW) of 24.5 ± 0.53 lb were used in a 21 d growth trial to determine the standardized total tract digestible phosphorus (STTD P) requirement of nursery pigs from 25 to 50 lb fed diets containing 1,000 phytase units (FYT). Pigs were weaned at approximately 19 d of age and allotted to pens according to gender and sow farm of origin. There were 12 replicate pens per treatment and 24 to 27 pigs per pen. Pens of pigs were randomly allotted to experimental diets based on average BW 25 d post-weaning, in a randomized complete block design. The 7 dietary treatments consisted of 0.30, 0.33, 0.38, 0.43, 0.48, 0.53, and 0.58% STTD P, which included the expected release of phytase. These values represented 90, 100, 115, 130, 145, 160 and 175% of the National Research Council (NRC) requirement estimate for STTD P for pigs weighing between 25 to 55 lb, respectively. The diets contained 1,000 FYT of Ronozyme Hiphos 2500 (DSM Nutritional Products, Inc., Parsippany, NJ) with assumed releasing values of 0.15% available P and 0.132% STTD P. Two corn-soybean meal-based diets were formulated to contain 0.30 and 0.58% STTD P by increasing the inclusion of limestone and monocalcium phosphate at the expense of corn, maintaining a similar 1.17:1 total Ca:P ratio across treatments. These two diets were blended using a robotic feeding system to achieve the intermediate STTD P levels. Increasing STTD P quadratically improved (P \u3c 0.05) average daily gain (ADG) and feed efficiency (F/G). The greatest improvement was observed as the STTD P was increased from 0.30 to 0.43% for ADG, and from 0.30 to 0.38% for F/G, with no further improvements thereafter. Final BW and average daily feed intake (ADFI) increased linearly (P \u3c 0.05) up to the highest STTD P level. The grams of STTD P intake per day and grams of STTD P intake per kilogram of gain where growth rate reached a point of diminishing returns in response to increased STTD P were greater than the NRC requirement estimates. Income over feed cost improved quadratically (P \u3c 0.05), with the highest income being observed at 0.43% STTD P. For both ADG and feed efficiency (modeled as G:F), the broken-line linear (BLL) model demonstrated best fit. The BLL plateau was estimated at 0.40% STTD P for ADG and at 0.37% STTD P for G:F. In conclusion, the estimated STTD P requirement for nursery pigs from 25 to 50 lb fed diets containing 1,000 units of phytase ranged from 0.37 to 0.43% depending on the response criteria. These results indicate that STTD P required to optimize performance and economic return of 25- to 50-lb pigs is greater than the NRC requirement estimate

Evaluation of Phase Feeding Strategies and Lysine Specifications for Grow-Finish Pigs on Growth Performance and Carcass Characteristics

The objective of this study was to compare phase feeding strategies for grow-finish pigs using the estimated lysine requirements for optimal growth and feed efficiency compared to a standard strategy. A total of 1,188 pigs (PIC 359 × 1050; initially 61.5 lb BW) were used in a randomized complete block design with 27 pigs per pen and 11 pens per treatment. The treatments consisted of: MAX, a 4-phase feeding program with lysine levels for maximum growth (1.13, 0.96, 0.82, and 0.77% SID Lys in Phases 1 to 4, respectively); STD, a standard 4-phase feeding program for optimal income over feed cost (1.02, 0.87, 0.76, and 0.67% SID Lys in Phases 1 to 4, respectively); STD/ MAX, a 4-phase feeding program based on standard lysine levels in early finishing and lysine levels for maximum growth in late finishing (1.02, 0.87, 0.82, and 0.77% SID Lys in Phases 1 to 4, respectively); and 2-PHASE, a 2-phase feeding program based on the average estimated lysine requirements for maximum growth with 0.96% SID lysine for Phases 1 to 3 and 0.77% SID lysine during Phase 4. The four phases were from approximately 60 to 110, 110 to 160, 160 to 220, and 220 to 280 lb, respectively. The experimental diets were based on corn, distillers dried grains with solubles, and soybean meal. Lysine levels were achieved by manipulating the ratio of corn to soybean meal. Overall, from d 0 to 117, pigs fed the 2-PHASE regimen had increased ADG (P \u3c 0.05) compared to pigs fed the STD regimen, and feeding either the MAX or STD/MAX regimen resulted in intermediate ADG. There was no evidence for differences in ADFI, F/G, or final BW among dietary regimens. Also, no evidence for differences was observed across the dietary treatments for the carcass traits HCW, yield, backfat, loin depth, or lean percentage. For economics, the STD feeding program resulted in the lowest (P \u3c 0.001) feed cost per pig and feed cost per lb of gain compared to the other 3 programs. Revenue and income over feed costs per pig were similar across the feeding programs. In conclusion, feeding lysine levels for maximum growth and efficiency in either a 2- or 4-phase feeding program results in the same growth performance and feed cost. A broad range of lysine specifications within the levels tested herein can be utilized in grow-finish diets without compromising income over feed cost