Improving Health Care

This essay confirms Dr. Bornemeier\u27s personal concern as well as organized medicine\u27s concern for the medically deprived. At the same time it realistically appraises the progress which the profession has made to meet the medical-social challenges of our times

Magnetoresistive Elemente in Kombination mit Schottky-Barrieren auf Galliumarsenid

Bornemeier J. Magnetoresistive elements in combination with Schottky barriers on gallium arsenide. Bielefeld (Germany): Bielefeld University; 2005.Magnetische Tunnelelemente kombiniert mit Schottky-Barrieren erlauben die Untersuchung ballistischer Ströme mit Energien um 1eV. Zu diesem Zwecke wurden TMR-Elemente mit dem folgenden Schichtstapel direkt auf n-Galliumarsenid gesputtert: 4-10nm Co/ 1.8nm Alox/ 4nm Py/ 12nm MnIr/ 50nm Cu/ 50nm Au. Der injizierte Strom ist, abhängig von der Kobaltdicke, 4-5 mal kleiner als der Tunnelstrom. Dieses, und die Tatsache, dass der Strom hochpolarisiert ist, macht TMR-Schottky-Hybridelemente zu idealen Spininjektoren. Durch eine Variation der Kobaltdicke können Spinabklinglängen bestimmt werden. Bei 1.2V Bias und 10K Temperatur beträgt diese für die Majoritätsladungsträger 6+/-0.9nm und für die Minoritätsladungsträger weniger als 2nm. Zusätzlich wurden BEEM Experimente an Spinvalves durchgeführt.The combination of a magnetic tunnel junction and a Schottky barrier allows the observation of spin scattering of ballistic electrons at energies around 1eV. For this layer stacks of 4-10nm Co/ 1.8nm Alox/ 4nm Py/ 12nm MnIr/ 50nm Cu/ 50nm Au on (100)-GaAs are deposited and subsequently patterned by e-beam lithography. The injected current is (depending on the base thickness) 4-5 orders of magnitude smaller than the tunnel current. The adjustable current amplitude and the high spin polarization make these hybride junctions a promising candidate as spin injector into semiconductors. Varying the base thickness, the spin attenuation length of the majority electrons can be estimated to be 6+/-0.9nm and for minority electrons <2nm at 10K and 1.2V bias. Additionally BEEM experiments on spinvalves have been accomplished

The satisfactory growth and development at 2 years of age of the INTERGROWTH-21st Fetal Growth Standards cohort support its appropriateness for constructing international standards.

BACKGROUND: The World Health Organization recommends that human growth should be monitored with the use of international standards. However, in obstetric practice, we continue to monitor fetal growth using numerous local charts or equations that are based on different populations for each body structure. Consistent with World Health Organization recommendations, the INTERGROWTH-21st Project has produced the first set of international standards to date pregnancies; to monitor fetal growth, estimated fetal weight, Doppler measures, and brain structures; to measure uterine growth, maternal nutrition, newborn infant size, and body composition; and to assess the postnatal growth of preterm babies. All these standards are based on the same healthy pregnancy cohort. Recognizing the importance of demonstrating that, postnatally, this cohort still adhered to the World Health Organization prescriptive approach, we followed their growth and development to the key milestone of 2 years of age. OBJECTIVE: The purpose of this study was to determine whether the babies in the INTERGROWTH-21st Project maintained optimal growth and development in childhood. STUDY DESIGN: In the Infant Follow-up Study of the INTERGROWTH-21st Project, we evaluated postnatal growth, nutrition, morbidity, and motor development up to 2 years of age in the children who contributed data to the construction of the international fetal growth, newborn infant size and body composition at birth, and preterm postnatal growth standards. Clinical care, feeding practices, anthropometric measures, and assessment of morbidity were standardized across study sites and documented at 1 and 2 years of age. Weight, length, and head circumference age- and sex-specific z-scores and percentiles and motor development milestones were estimated with the use of the World Health Organization Child Growth Standards and World Health Organization milestone distributions, respectively. For the preterm infants, corrected age was used. Variance components analysis was used to estimate the percentage variability among individuals within a study site compared with that among study sites. RESULTS: There were 3711 eligible singleton live births; 3042 children (82%) were evaluated at 2 years of age. There were no substantive differences between the included group and the lost-to-follow up group. Infant mortality rate was 3 per 1000; neonatal mortality rate was 1.6 per 1000. At the 2-year visit, the children included in the INTERGROWTH-21st Fetal Growth Standards were at the 49th percentile for length, 50th percentile for head circumference, and 58th percentile for weight of the World Health Organization Child Growth Standards. Similar results were seen for the preterm subgroup that was included in the INTERGROWTH-21st Preterm Postnatal Growth Standards. The cohort overlapped between the 3rd and 97th percentiles of the World Health Organization motor development milestones. We estimated that the variance among study sites explains only 5.5% of the total variability in the length of the children between birth and 2 years of age, although the variance among individuals within a study site explains 42.9% (ie, 8 times the amount explained by the variation among sites). An increase of 8.9 cm in adult height over mean parental height is estimated to occur in the cohort from low-middle income countries, provided that children continue to have adequate health, environmental, and nutritional conditions. CONCLUSION: The cohort enrolled in the INTERGROWTH-21st standards remained healthy with adequate growth and motor development up to 2 years of age, which supports its appropriateness for the construction of international fetal and preterm postnatal growth standards

Just What Do You “Mean”?

In Ancient Greece the Pythagoreans were interested in three means. The means were the arithmetic, geometric, and harmonic. The arithmetic mean played an important role in the observations of Galileo. Along with the arithmetic mean, the geometric and harmonic mean (formerly known as the subcontrary mean) are said to be instrumental in the development of the musical scale. As we explore the three Pythagorean Means we will discover their unique qualities and mathematical uses for helping us solve problems

A Pragmatic Analysis of Helicopter Response to Turbulent Air Wake in a Shipboard Flight Deck Environment

An experiment consists of a remote-controlled T-REX 600E Pro helicopter piloted above an underway 108-foot Patrol Craft’s (YP) flight deck to analyze the effect of ReH ≈ 3.4×10 5 turbulent ship air wake on helicopter angular motion. The motion is measured by an inertial measurement unit (IMU) sensor mounted on the helicopter transmitting variably-spaced data in a 3-D Cartesian reference frame. Data is collected with the helicopter in locations above the flight deck which closely match actual takeoff/landing positions of US Navy H-60 helicopters above flight decks of air-capable ships (CG/DDG/FFG). This method is both an indirect way of qualifying the flow field and a practical way of measuring the actual effects of ship air wake turbulence on rotary-wing aircraft. Fourier analysis is performed on helicopter angular velocities to determine predominant frequencies of motion. Frequencies of this motion are compared with both pilot input frequencies and vortex shedding frequencies of incompressible, subsonic flow around 2-D and 3-D backward-facing step (BFS) geometries. These frequencies of motion are discussed in relation to the pilot’s perception of motion and the phenomena of spatial disorientation. The spectra of pilot inputs in roll and pitch were found to have cutoff frequencies of 0.5 Hz and 0.7 Hz, respectively, which agree well with full-size helicopter pilot autospectra. A 3 Hz non-pilot initiated disturbance is noted; the source of this disturbance is thought to be due to interactions with airflow over the flight deck hangar or dynamic effects of the flybar on the helicopter