Conversion of a piston-cylinder dimensional dataset to the effective area of a mechanical pressure generator.

Recent developments in diameter metrology at NIST have improved the dimensional characterization of piston-cylinder assemblies (PCAs) to unprecedented precision. For the newest generation of PCAs, the standard uncertainty in the measurement of the outer diameter is 12 nm, while uncertainty in the measurement of the inner diameter is 14 nm. With a high-accuracy dimensional dataset in hand, the task of determining the pressure generated by a specific PCA is reduced to converting the diameter (and straightness and roundness) to an effective area (and distortion coefficient).

Expansivity of Fused Quartz Glass Measured Within 6 × 10 K.

A method is described to measure the thermal expansion coefficient of fused quartz glass. The measurement principle is to monitor the change in resonance frequency of a Fabry-Perot cavity as its temperature changes; the Fabry-Perot cavity is made from fused quartz glass. The standard uncertainty in the measurement was less than 0.

Measured relationship between thermodynamic pressure and refractivity for six candidate gases in laser barometry.

Laser refractometers are approaching accuracy levels where gas pressures in the range 1 Pa < < 1 MPa inferred by measurements of gas refractivity at a known temperature will be competitive with the best existing pressure standards and sensors. Here, the authors develop the relationship between pressure and refractivity , via measurement at 293.1529(13) K and = 632.

Who Leads? Who Follows? Measuring Issue Attention and Agenda Setting by Legislators and the Mass Public Using Social Media Data.

Are legislators responsive to the priorities of the public? Research demonstrates a strong correspondence between the issues about which the public cares and the issues addressed by politicians, but conclusive evidence about who leads whom in setting the political agenda has yet to be uncovered. We answer this question with fine-grained temporal analyses of Twitter messages by legislators and the public during the 113th US Congress. After employing an unsupervised method that classifies tweets sent by legislators and citizens into topics, we use vector autoregression models to explore whose priorities more strongly predict the relationship between citizens and politicians.

Candidates to Replace R-12 as a Radiator Gas in Cherenkov Detectors.

Dichlorodifluoromethane (R-12) has been widely used as a radiator gas in pressure threshold Cherenkov detectors for high-energy particle physics. However, that compound is becoming unavailable due to the Montreal Protocol. To find a replacement with suitably high refractive index, we use a combination of theory and experiment to examine the polarizability and refractivity of several non-ozone-depleting compounds.

Cell-based refractometer for pascal realization.

We describe a method for determining the density of helium via measurements of optical refractivity. In combination with the equation of state, this allows realization of the pascal. Our apparatus is based on the integration of a gas triple-cell into a quasi-monolithic heterodyne interferometer: the stability of the interferometer is ±50  pm over 10 h.

The Malleable Efficacy of Willpower Theories.

Emerging research documents the self-control consequences of individuals' theories regarding the limited nature of willpower, such that unlimited theorists consistently demonstrate greater self-control than limited theorists. The purpose of the present research was to build upon prior work on self-validation and perceptions of mental fatigue to demonstrate when self-control is actually impaired by endorsing an unlimited theory and-conversely-enhanced by endorsing a limited theory. Four experiments show that fluency reinforces the documented effects of individuals' willpower theories on self-control, while disfluency reverses the documented effects of individuals' willpower theories on self-control.

Comparison measurements of low-pressure between a laser refractometer and ultrasonic manometer.

We have developed a new low-pressure sensor which is based on the measurement of (nitrogen) gas refractivity inside a Fabry-Perot cavity. We compare pressure determinations via this laser refractometer to that of well-established ultrasonic manometers throughout the range 100 Pa to 180 000 Pa. The refractometer demonstrates 10(-6) ⋅ p reproducibility for p > 100 Pa, and this precision outperforms a manometer.

Recent improvement and projected worsening of weather in the United States.

As climate change unfolds, weather systems in the United States have been shifting in patterns that vary across regions and seasons. Climate science research typically assesses these changes by examining individual weather indicators, such as temperature or precipitation, in isolation, and averaging their values across the spatial surface. As a result, little is known about population exposure to changes in weather and how people experience and evaluate these changes considered together.

Performance of a dual Fabry-Perot cavity refractometer.

We have built and characterized a refractometer that utilizes two Fabry-Perot cavities formed on a dimensionally stable spacer. In the typical mode of operation, one cavity is held at vacuum, and the other cavity is filled with nitrogen gas. The differential change in length between the cavities is measured as the difference in frequency between two helium-neon lasers, one locked to the resonance of each cavity.

Impact of patient and navigator race and language concordance on care after cancer screening abnormalities.

Background: Patient navigation improves the timely diagnosis of cancer among minorities, but little is known about the effects of patient and navigator race and language concordance on health outcomes.

Methods: The authors investigated the effects of patient and navigator race and language concordance on the time to diagnosis of cancer screening abnormalities among participants in the Boston Patient Navigation Research Program, a clinical effectiveness trial for women who had breast or cervical cancer screening abnormalities identified from January 1, 2007 to December 31, 2008. Hazard ratios and 95% confidence intervals were estimated using proportional hazards regression adjusting for clinical and demographic factors.

Flipping the switch: power, social dominance, and expectancies of mental energy change.

Research suggests that high levels of interpersonal power can promote enhanced executive functioning capabilities. The present work explored whether this effect is contingent upon expectancies concerning power's downstream cognitive consequences. Study 1 showed that social dominance orientation (SDO) predicted idiosyncratic expectancies of mental energy change toward interpersonal power.

The role of retrobulbar and retinal circulation on optic nerve head and retinal nerve fibre layer structure in patients with open-angle glaucoma over an 18-month period.

Background/aims: Evidence suggests that vascular abnormalities play a role in the pathogenesis of open-angle glaucoma (OAG) in some patients. This study aims to assess changes in retrobulbar and retinal blood flow over time in patients with glaucoma and examine their relationship to glaucomatous progression, as determined by retinal and optic nerve structure.

Methods: In this observational study, 103 patients with OAG were examined at baseline and 18 months follow-up.

Intraocular pressure, blood pressure, and retinal blood flow autoregulation: a mathematical model to clarify their relationship and clinical relevance.

Purpose: This study investigates the relationship between intraocular pressure (IOP) and retinal hemodynamics and predicts how arterial blood pressure (BP) and blood flow autoregulation (AR) influence this relationship.

Methods: A mathematical model is developed to simulate blood flow in the central retinal vessels and retinal microvasculature as current flowing through a network of resistances and capacitances. Variable resistances describe active and passive diameter changes due to AR and IOP.

Impact of depression on the intensity of patient navigation for women with abnormal cancer screenings.

Patient navigation is increasingly being used to support vulnerable patients to receive timely and quality medical care. We sought to understand whether patients with depression utilize additional patient navigation services after abnormal cancer screening. We compared depressed and non-depressed women using three different measures of intensity of patient navigation: number of patient-navigator encounters, encounter time, and number of unique barriers to care.

Weak-value thermostat with 0.2 mK precision.

A new laser-based thermostat sensitive to 0.2 mK at room temperature is reported. The method utilizes a fluid-filled prism and interferometric weak-value amplification to sense nanoradian deviations of a laser beam: due to the high thermo-optic coefficient of the fluid (colorless fluorocarbon), the deviation angle through the prism is sensitive to temperature.

Generic medications in ophthalmology.

The purpose of this review is to discuss the process of genericisation of medications in the US and Europe with a focus on ophthalmic drugs. Regulatory guidelines of the US Food and Drug Administration and the European Medicines Agency will be discussed, and the advantages and concerns of genericisation will be explored. We will look at various studies concerning the safety and efficacy of generic drugs compared to their branded counterparts.

Boston Patient Navigation Research Program: the impact of navigation on time to diagnostic resolution after abnormal cancer screening.

Background: There is a need for controlled studies to assess the impact of patient navigation in vulnerable cancer populations.

Methods: Boston Patient Navigation Research Program conducted a quasi-experimental patient navigation intervention across six federally qualified inner-city community health centers, three assigned to a breast cancer navigation intervention and three assigned to a cervical cancer navigation intervention; each group then served as the control for the other. Eligible women had an abnormal breast or cervical cancer screening test conducted at one of the participating health centers during a baseline (2004-2005) or intervention period (2007-2008).

The Effect of Diluted Penetration Enhancer in Nebulized Mist versus Liquid Drop Preparation Forms on Retrobulbar Blood Flow in Healthy Human Subjects.

The aim of this study was to compare the effects of nebulized mist and liquid drop applications on retrobulbar blood flow. A prospective, non-randomized clinical trial was used to collect data from 40 healthy human eyes. Color Doppler Imaging determined peak systolic (PSV) and end diastolic (EDV) blood flow velocities and resistance index (RI) in the ophthalmic artery after both applications.

Absolute refractometry of dry gas to ±3 parts in 10⁹.

We present a method of measuring the refractive index of dry gases absolutely at 632.8 nm wavelength using a Fabry-Perot cavity with an expanded uncertainty of <3×10⁻⁹ (coverage factor k=2). The main contribution to this uncertainty is how well vacuum-to-atmosphere compression effects (physical length variation) in the cavities can be corrected.

The reverse double standard in perceptions of student-teacher sexual relationships: the role of gender, initiation, and power.

The present study tested the prediction that male teachers are judged more harshly than female teachers for engaging in heterosexual intercourse with a student. One-hundred and eighty-seven adults (116 women, 71 men) evaluated a hypothetical newspaper article describing an alleged student-teacher relationship as part of a 2 (Gender Dyad: Male Teacher/Female Student or Female Teacher/Male Student) x 2 (Initiator: Student or Teacher) between-subjects design. As expected, a reverse sexual double standard was revealed, in which participants judged situations involving male teachers more harshly than they judged situations involving female teachers, but only when the sexual contact was teacher-initiated.

An Optical Frequency Comb Tied to GPS for Laser Frequency/Wavelength Calibration.

Optical frequency combs can be employed over a broad spectral range to calibrate laser frequency or vacuum wavelength. This article describes procedures and techniques utilized in the Precision Engineering Division of NIST (National Institute of Standards and Technology) for comb-based calibration of laser wavelength, including a discussion of ancillary measurements such as determining the mode order. The underlying purpose of these calibrations is to provide traceable standards in support of length measurement.

Goldmann applanation tonometry and dynamic contour tonometry are not correlated with central corneal thickness in primary open angle glaucoma.

Purpose: To compare intraocular pressure (IOP) measured by Goldmann applanation tonometry (GAT) and dynamic contour tonometry (DCT) and assess their relationship to central corneal thickness (CCT) in patients with primary open angle glaucoma (OAG).

Patients And Methods: GAT, DCT, and CCT were assessed in 116 patients with OAG [mean age 65.9 (10.

Caregiver psychoeducation for first-episode psychosis.

Introduction: International best-practice guidelines for the management of first-episode psychosis have recommended the provision of psychoeducation for multifamily groups. While there is ample evidence of their efficacy in multiepisode psychosis, there is a paucity of evidence supporting this approach specifically for first-episode psychosis. We sought to determine whether a six-week caregiver psychoeducation programme geared specifically at first-episode psychosis improves caregiver knowledge and attitudes.