Riding the Yield Curve: Reprise

We investigate the efficacy of riding the yield curve. This strategy dictates holding longer-term treasury bills when the yield curve is upwardsloping. We find that the strategy is surprisingly effective. it stochastically dominates buying and holding shorter-term bills for large subperiods, and nearly dominates for the entire sample period, 1949-1988. Our empirical results suggest that abnormal profit opportunities are available from selectively increasing the maturity of a short-term portfolio.

Some Indicators of Manganese and Copper Adequacy in Some Infant Formulas for Baby Pigs and Infants

The objective of the study was to ascertain whether some infant formulas provide sufficient amounts of manganese and copper for adequate nutrition, Twelve piglets, within the first week of life, were divided by sex, litter and weight into two treatment groups. Both groups received concentrated Isomil a soy-based infant formula and distilled water ad libitum. Isomil was analyzed and found to contain 1.05ppm manganese and .98ppm copper. The supplemented group received an additional 30.6mg manganese and 6.76mg copper per can (388m1) of concentrated Isomil. Weight gains we re not significantly different. Manganese and copper levels were significantly greater in the livers of the supplemented group. The supplemented group also had significantly higher manganese and zinc in femurs. These were determined by atomic absorption spectrophotometry. Serum copper and manganese were determined using an atomic absorption spectrophotometer equipped with a graphite furnace. The supplemented group had a significantly higher serum manganese and copper at the end of the study than the unsupplemented group. Within a group, the unsupplemented group had a significantly higher serum manganese and the supplemented group had a significantly higher serum copper in week five versus week one. No significant differences or lesions were found upon histopathological examination of spinal cord and rib tissue from the piglets. Birth weight, two month and six month weight, and serum levels of copper and manganese from human infants fed breast milk versus Similac were studied. Serum copper was significantly greater at two months, and serum manganese was significantly greater at six months in the breast-fed infants. Although no clinical deficiency symptoms were observed in the infant pigs, tissue levels were significantly decreased in the unsupplemented group. The significantly greater se rum copper and manganese levels of the breast-fed infants may be related to different bioavailability of these minerals from breast milk versus Similac or other infant formulas. Many marginal deficiencies probably go undetected. It is recommended that infant formulas contain a minimum concentration of manganese and copper which will provide infants of 0 - 6 months of age with .5 - .7mg/day, to meet the current estimated safe and adequate recommendations

An eccentrically biased rehabilitation program early after TKA surgery

Journal ArticleRehabilitation services are less-studied aspects of the management following total knee arthroplasty (TKA) despite long-term suboptimal physical functioning and chronic deficits in muscle function. This paper describes the preliminary findings of a six-week (12 session) eccentrically-biased rehabilitation program targeted at deficits in physical function and muscle function, initiated one month following surgery. A quasiexperimental, one group, pretest-posttest study with thirteen individuals (6 female, 7 male; mean age 57 ? 7 years) examined the effectiveness of an eccentrically-biased rehabilitation program. The program resulted in improvements in the primary physical function endpoints (SF-36 physical component summary and the six-minute walk test) with increases of 59% and 47%, respectively. Muscle function endpoints (knee extension strength and power) also increased 107% and 93%, respectively. Eccentrically-biased exercise used as an addition to rehabilitation may help amplify and accelerate physical function following TKA surgery

Targeting anabolic impairment in response to resistance exercise in older adults with mobility impairments: potential mechanisms and rehabilitation approaches

pre-printMuscle atrophy is associated with healthy aging (i.e., sarcopenia) and may be compounded by comorbidities, injury, surgery, illness, and physical inactivity. While a bout of resistance exercise increases protein synthesis rates in healthy young skeletal muscle, the effectiveness of resistance exercise to mount a protein synthetic response is less pronounced in older adults. Improving anabolic sensitivity to resistance exercise, thereby enhancing physical function, is most critical in needy older adults with clinical conditions that render them "low responders". In this paper, we discuss potential mechanisms contributing to anabolic impairment to resistance exercise and highlight the need to improve anabolic responsiveness in low responders. This is followed with evidence suggesting that the recovery period of resistance exercise provides an opportunity to amplify the exercise-induced anabolic response using protein/essential amino acid ingestion. This anabolic strategy, if repeated chronically, may improve lean muscle gains, decrease time to recovery of function during periods of rehabilitation, and overall, maintain/improve physical independence and reduce mortality rates in older adults

Ultrasonic Positioning System for Electric Road System

Elonroad is a company that is looking into the possibility to charge electric vehicle on road. The conductor implemented on the driveway has a characteristic shape. The scope of this master thesis project is to identify the shape of the conductor and determine the relative position of the vehicle to the conductor using ultrasonic sensors. The goal is to have an update frequency of 30 Hz and a positioning error of maximum 2 cm. During the project a serial system containing 7 ultrasonic modules has been built. The sensor modules are mounted in an array and placed parallel to the road and perpendicular to the vehicles intended direction of travel. The ultrasonic modules are placed with a center distance of 10 cm on the array. A cross-correlation algorithm was implemented to determine the distance to the surface below each of the ultrasonic modules. The method to find the relative position of the vehicle uses a modified convolution algorithm which is proven to work under ideal circumstances. The distance measurement from the modules to ground can differ roughly +/-8 mm, this originates from the wavelength of the 40 kHz ultrasonic signal in air, the +/-8 mm error can, according to simulations give a positioning error of up to 5 cm. Simulations has indicated that +/-4 mm will give a positioning error less than, or equal to, 2 cm. The update frequency is assumed to be around 20 Hz, where the largest part is due to calculation time of the distance to ground. It can be lowered with more effective algorithms or with a more powerful microcontroller.Electric vehicles can charge their batteries on road by connecting to a conductor integrated in the roadway. In this specific case the integrated conductor consists in an elevated structure. This structures location relative the car needs to be tracked to ensure the car stays connected

Symmetry groupoids and patterns of synchrony in coupled cell networks

A coupled cell system is a network of dynamical systems, or “cells,” coupled together. Such systems can be represented schematically by a directed graph whose nodes correspond to cells and whose edges represent couplings. A symmetry of a coupled cell system is a permutation of the cells that preserves all internal dynamics and all couplings. Symmetry can lead to patterns of synchronized cells, rotating waves, multirhythms, and synchronized chaos. We ask whether symmetry is the only mechanism that can create such states in a coupled cell system and show that it is not. The key idea is to replace the symmetry group by the symmetry groupoid, which encodes information about the input sets of cells. (The input set of a cell consists of that cell and all cells connected to that cell.) The admissible vector fields for a given graph—the dynamical systems with the corresponding internal dynamics and couplings—are precisely those that are equivariant under the symmetry groupoid. A pattern of synchrony is “robust” if it arises for all admissible vector fields. The first main result shows that robust patterns of synchrony (invariance of “polydiagonal” subspaces under all admissible vector fields) are equivalent to the combinatorial condition that an equivalence relation on cells is “balanced.” The second main result shows that admissible vector fields restricted to polydiagonal subspaces are themselves admissible vector fields for a new coupled cell network, the “quotient network.” The existence of quotient networks has surprising implications for synchronous dynamics in coupled cell systems