Sensor Noise in LISA Pathfinder: In-Flight Performance of the Optical Test Mass Readout.

We report on the first subpicometer interferometer flown in space. It was part of ESA's Laser Interferometer Space Antenna (LISA) Pathfinder mission and performed the fundamental measurement of the positional and angular motion of two free-falling test masses. The interferometer worked immediately, stably, and reliably from switch on until the end of the mission with exceptionally low residual noise of 32.0_{-1.7}^{+2.4} fm/sqrt[Hz], significantly better than required. We present an upper limit for the sensor performance at millihertz frequencies and a model for the measured sensitivity above 200 mHz.

Analysis of the accuracy of actuation electronics in the laser interferometer space antenna pathfinder.

The Laser Interferometer Space Antenna Pathfinder (LPF) main observable, labeled Δg, is the differential force per unit mass acting on the two test masses under free fall conditions after the contribution of all non-gravitational forces has been compensated. At low frequencies, the differential force is compensated by an applied electrostatic actuation force, which then must be subtracted from the measured acceleration to obtain Δg. Any inaccuracy in the actuation force contaminates the residual acceleration. This study investigates the accuracy of the electrostatic actuation system and its impact on the LPF main observable. It is shown that the inaccuracy is mainly caused by the rounding errors in the waveform processing and also by the random error caused by the analog to digital converter random noise in the control loop. Both errors are one order of magnitude smaller than the resolution of the commanded voltages. We developed a simulator based on the LPF design to compute the close-to-reality actuation voltages and, consequently, the resulting actuation forces. The simulator is applied during post-processing the LPF data.

The Tingathe Surge: a multi-strategy approach to accelerate HIV case finding in Malawi.

SETTING: Nineteen health facilities in rural, southeastern Malawi. OBJECTIVE: To describe the implementation and results of a 6-week intervention to accelerate human immunodeficiency virus (HIV) case finding. DESIGN: Six HIV testing strategies were simultaneously implemented. Routinely collected data from Ministry of Health registers were used to determine the number of HIV tests performed and of new cases identified. The weekly averages of the total number of tests and new cases before and during the intervention were compared. Testing by age group and sex was described. The percentage yield of new cases was compared by testing strategy. RESULTS: Of 29 703 HIV tests conducted, 1106 (3.7%) were positive. Of the total number of persons tested, 69.5% were women and 75.5% were aged >15 years. The yield of positive test results was 3.5% among women, 4.3% among men, 4.4% among those aged >15 years and 1.5% among those aged ⩽15 years. The average weekly number of tests increased 106.7% from 3337 to 6896 (P = 0.002). The average weekly number of positive cases identified increased 51.9% from 158 to 240 (P = 0.017). The testing strategy with the highest yield resulted in a 6.0% yield; the lowest was 1.3%. The yield for all strategies, except one, was highest in adult men. CONCLUSION: A multi-strategy approach to HIV testing and counseling can be an effective means of accelerating HIV case finding.

LISA Pathfinder Performance Confirmed in an Open-Loop Configuration: Results from the Free-Fall Actuation Mode.

We report on the results of the LISA Pathfinder (LPF) free-fall mode experiment, in which the control force needed to compensate the quasistatic differential force acting on two test masses is applied intermittently as a series of "impulse" forces lasting a few seconds and separated by roughly 350 s periods of true free fall. This represents an alternative to the normal LPF mode of operation in which this balancing force is applied continuously, with the advantage that the acceleration noise during free fall is measured in the absence of the actuation force, thus eliminating associated noise and force calibration errors. The differential acceleration noise measurement presented here with the free-fall mode agrees with noise measured with the continuous actuation scheme, representing an important and independent confirmation of the LPF result. An additional measurement with larger actuation forces also shows that the technique can be used to eliminate actuation noise when this is a dominant factor.

Observation of the naive-T-odd Sivers effect in deep-inelastic scattering.

Azimuthal single-spin asymmetries of leptoproduced pions and charged kaons were measured on a transversely polarized hydrogen target. Evidence for a naive-T-odd, transverse-momentum-dependent parton distribution function is deduced from nonvanishing Sivers effects for pi(+), pi(0), and K(+/-), as well as in the difference of the pi(+) and pi(-) cross sections.

Electrical stimulation influences mineral formation of osteoblast-like cells in vitro.

The aim of the present study was to assess the structure of newly formed mineral crystals after electrical stimulation of osteoblast-like cells in vitro. Pulsed electrical stimulation was coupled capacitively or semi-capacitively to primary osteoblast-like cells derived from bovine metacarpals. Computer calculations revealed that the chosen input signal (saw-tooth, 100 V, 63 ms width, 16 Hz repetition rate) generated a short pulsed voltage drop of 100 microV (capacitive coupled mode) and of 350 microV (semi-capacitive coupled mode) across the cell-matrix layer. Stimulated cultures showed an enhanced mineral formation compared to the non stimulated controls. In cultures exposed to capacitively coupled electric fields and in control cultures nodules and mineralized globules were found. Nodules with a diameter of less than 200 nm covered the cell surface, whereas mineral globules with a diameter of up to 700 nm formed characteristic mineral deposits in the vicinity of the cells similar to biomineral formations occurring in mineralizing tissues. In contrast, large rod-shaped crystals were found in cultures stimulated by semi-capacitive coupled electric fields, indicating a non-physiological precipitation process. In conclusion, osteoblasts in culture are sensitive to electrical stimulation resulting in an enhancement of the biomineralization process.

Capacitively coupled electric fields accelerate proliferation of osteoblast-like primary cells and increase bone extracellular matrix formation in vitro.

Over the last few years, electric and electromagnetic fields have gained more and more significance in the therapy of bone fracture healing and bone disease. Yet, the underlying mechanisms on a cellular and molecular level are not completely understood. In the present study we have investigated the effects of capacitively coupled, pulsed electric fields on cellular proliferation, alkaline phosphatase activity, and matrix protein synthesis of osteoblast-like primary cells in vitro. Cells were derived from bovine periosteum and electrically stimulated by saw-tooth pulses of 100 V external voltage and 16 Hz frequency. This corresponds to an electric field of 6 kV/m across the cell membranes as could be shown by computer simulation. Field application caused acceleration of cell culture development. A significant increase of proliferation concurrent with an enhancement of alkaline phosphatase activity was observed in sub-confluent cultures. Exposure of confluent osteoblast-like primary cells to electric fields resulted in enhanced synthesis and secretion of extracellular matrix-related proteins. These findings suggest that capacitively coupled electric fields accelerate bone cell proliferation and differentiation in vitro and enhance the synthesis of cells leading to promoted matrix formation and maturation.

Expert nursing assistant care activities.

Expert nursing assistants (NAs) described a broad range of care activities provided for nursing home residents. Data from in-depth interviews were analyzed using a naturalistic inquiry approach. Functional care activities addressed activities of daily living. Seven types of psychosocial care activities promoted emotional and mental health. NAs also described activities beyond the scope of their training, yet delegated by licensed nurses. Identification of expert NA contributions to resident care, proposed as the highest level of NA care possible, can guide development of educational programs and evaluation instruments. Awareness of delegated activities can direct research regarding their safety and legality.

Patient satisfaction with nurse practitioner care in primary care.

This quantitative, descriptive pilot study assessed patient satisfaction with care provided by four nurse practitioners using a modified version of the Di Tomasso-Willard Patient Satisfaction Questionnaire. Results indicated high satisfaction with care in all groups, but there were differences among the groups on 26 percent of the items and on three of the five subscales. The implication is that nurse practitioners need to identify and improve those dimensions of care for which patients are less satisfied.

Accuracy of nurse aides' functional health assessments of nursing home residents.

BACKGROUND: Nurse aides provide assessments of nursing home residents' functional health for use in care planning and quality assurance. Nurse practitioner assessments can serve as a standard for analysis of nurse aides' accuracy. This study compared nurse aide to nurse practitioner assessments of nursing home residents' functional health with regard to possible bias and extent of correlation. METHODS: Nurse aides' accuracy in assessing nursing home residents' activities of daily living was evaluated by comparisons to assessments performed by a master's-prepared nurse practitioner using four functional assessment instruments: the Barthel Index, the Katz Index of Activities of Daily Living, the Multidimensional Observation Scale for Elderly Subjects, and the Scaled Outcome Criteria. Data were collected in a 159-bed nonprofit nursing home licensed for skilled and intermediate care. Residents had a wide variety of functional and cognitive abilities and disabilities. Ninety-six nursing home residents provided data for the study. Functional health assessments by 24 nurse aides, each assessing 4 different nursing home residents, were compared to those of 1 nurse practitioner. Statistical analysis of accuracy used paired samples t-tests and Pearson product moment correlation coefficients. RESULTS: Nurse aide assessments and nurse practitioner assessments were highly correlated. Most functional health assessments evidenced no significant nurse aide bias. When bias was present it usually resulted from nurse aides electing more optimistic choices when using an assessment instrument that offered fewer response levels for rating residents. CONCLUSIONS: Nurse aides can accurately use well-calibrated instruments to assess nursing home residents' functional health. Demonstration of assessment accuracy in nurse aides, who provide the majority of direct care for nursing home residents, documented a valuable clinical resource for planning and evaluating resident care.

[Distribution and metabolism of azoxybenzene in the rat]. / Verteilung und Metabolismus von Azoxybenzen in der Ratte.

No sex differences could been shown after absorption and distribution of azoxybenzen in the rat. The highest level occur in the thyroid gland, the adrenals and in the fat tissues. The maximum level was reached 30 min. after application.

[Effect of various xenobiotics on the in vivo incorporation of 14C-acetate into cholesterol and other lipids in the rat]. / Die Wirkung einiger Fremdstoffe auf den in vivo-Einbau von [14C]-Azetat in Cholesterol und andere Lipide der Ratte.

Effects of some xenobiotics on the incorporation in vivo of [14C]-acetate into cholesterol and other lipids of the rat DDT, HCH, polychlorinated biphenyl, chlorcholine chloride, ethylenthiourea and mixtures of these substances were given to rats with the feed for 7 days. After that the incorporation of [14C]-acetate into phospholipids, triglycerides and cholesterol was studied in liver, serum, heart and brain. The influence of the xenobiotics on the synthesis, transport and accumulation differed among the various organs and lipids. Outstanding was an increase of 14C-phospholipids, -triglycerides and -cholesterol in the heart after administration of polychlorinated biphenyl. The effects in the peripheral organs were generally more distinct than on the liver.

[Effect of the phosphonic acid derivatives ethephon and trichlorphon on the incorporation in vivo of (14C)-acetate into cholesterol and other lipids in rats]. / Einfluss der Phosphonsäurederivate Ethephon und Trichlorphon auf den in vivo-Einbau von [14C]-Azetat in Cholesterol und andere Lipide der Ratte.

The effect of the phosphonic acid derivatives Ethephon and Trichlorphon on the incorporation of 14C-labelled acetate into lipids especially cholesterol was investigated. Adult Wistar rats were fed for 7 days diets containing 50 and 500 ppm, respectively, of the phosphonic acid derivatives. Both compounds caused a significant increase of the 14C-activity in lipids of serum, liver, heart, and brain. The effect of Ethephon was significantly more intense than that of Trichlorphon. The important finding was the Ethephon-induced increase of the [14C]-acetate incorporation into cholesterol which continued across all the tissues studied.

[Method for the control of (rat) liver functions by means of 14C-acetate for the toxicological analysis of foreign substances]. / Methode zur Kontrolle von (Ratten-)Leberfunktionen mit Hilfe von 14-C-Acetat für die toxikologische Untersuchung von Fremdstoffen.

The authors present a test procedure which permits to obtain, by means of a single carbon-14-labelled compound as structural element in a series of essential substances, a survey of important fields of liver function. Special attention was paid to cholesterol. Methodical studies resulted in an optimization of the application under in vivo and in vitro conditions, and of the isolation of carbon-14-labelled cholesterol, ester cholesterol and glucose as well as of carbon-14-labelled phospholipids, triglycerides, bile acids, proteins and nucleic acids as groups. A comparison of the experimental techniques demonstrated the advantages of in vivo application. The method and its validity are illustrated by an example (DDT). Its use in studies on various active principles will be dealt with in future communications.

[Effects of DDT and lindane on thyroid function in the rat]. / Zur Wirkung von DDT und Lindan auf die Schilddrüsenfunktion der Ratte

Using the previously described test method, the authors studied with the aid of iodine-131 labelled NaI the effects of daily doses of 30 and 75 mg DDT/kg of body weight, and of 12 and 36 mg of lindane/kg of body weight on the iodine and hormone metabolism in the rat. With DDT, the authors observed a marked increase of the thyroid mass and of the thyroid tri-iodothyronine and thyroxin levels and a simultaneous decrease of the thyroid iodine level. The values for serum iodine and protein-bound iodine were reduced. Serum thyroxin was slightly increased. Serum tri-iodothyronine was markedly increased, which was also true of the iodine fractions in the liver. Lindane was considerably less effective. Only the decrease of thyroid tri-iodothyronine and the simultaneous increase of thyroid thyroxin were striking. In the serum, both hormones remained unchanged. The values for the urine fractions of both the active principles were indicative of a hypofunction. The causes of the changes observed were discussed with regard to the findings of other authors. The present results permit the conclusion that the effects of the pesticides tested are obviously complex by nature.