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The effects of 63 MeV proton and 60Co gamma irradiation on the operation of 4.3 μm cutoff nBn photodetectors are demonstrated separately, and both are shown to yield a total ionizing dose (TID) effect. The effect is shown here in an InAsSbBi nBn detector and has been observed in other bulk alloy nBn detectors, and is unusual as it is notably absent in superlattice nBn detectors. The non-antireflection coated detectors exhibit a pre-radiation quantum efficiency of 17% at 3.3 μm wavelength and a dark current density of 50 μA/cm2, or roughly 300× the Rule 07 expectation, at their ideal operating voltage of −0.4 V bias at 150 K. Step-wise proton irradiation and in situ measurement indicate that the dark current increases to about 400× Rule 07 at the highest proton dose level of 150 krad(Si) (9.10 × 1011 p+/cm2), while the quantum efficiency is degraded at a relatively faster rate than the majority of analogous detectors characterized by our lab. Both the photocurrent and dark current are also shown to exhibit a turn-on voltage magnitude reduction of 100 mV following either gamma or proton irradiation, a trend which is attributable to negative trapped charge at the barrier interface (TID effect). This theory is further supported by an observed capacitance density magnitude reduction with dose and affirmed with Silvaco TCAD simulations. Following both proton exposure and subsequent anneal and gamma exposure and subsequent anneal; dark current, photocurrent, and CV all approach their pre-radiation baseline values. [ABSTRACT FROM AUTHOR]

InAsSbBi nBn photodetectors are demonstrated that are lattice-matched to the underlying GaSb substrate with a 4.32 μm wavelength cutoff at 150 K that is 0.3 μm longer than that of lattice-matched InAsSb at this temperature reflecting a 0.5% Bi mole fraction in the InAsSbBi active region. A low growth temperature was utilized to facilitate the incorporation of Bi, resulting in a minority carrier lifetime on the order of 24 ns in the InAsSbBi active region. Nevertheless, the detectors exhibit a quantum efficiency of 17% at 3.3 μm wavelength with a dark current density of 50 μA/cm2 at 150 K and −0.4 V bias and the strong photoresponse turn-on characteristic of a random alloy at 4.32 μm wavelength and 150 K. A shot noise-equivalent irradiance analysis indicates that this detectors' dark-current-limited noise-equivalent irradiance of 1012 cm−2 s−1 is two orders of magnitude greater than the Rule 07 expectation for this cutoff, and dark-current-limited shot noise-equivalent irradiance performance transitions to photon-limited at 1.7 × 1015 photons/cm2 s. [ABSTRACT FROM AUTHOR]

New adult patients (n = 212) were randomly assigned to 58 primary care resident physicians. Physician practice styles during initial and return visits were analyzed using the Davis Observation Code. Compared with initial patient visits, return visits were shorter, but more work-intensive. Return visits displayed significantly less technically oriented behavior (including history taking, physical examination, and treatment planning) and fewer discussions regarding use of addictive substances; however, there was more emphasis on health behaviors and active involvement of patients in their own care. These physicians' practice style differences between initial and return patient visits suggest that physician-patient familiarity affects what happens during the medical interview. [ABSTRACT FROM AUTHOR]

Our purpose was to explore why women are more likely than men to be diagnosed as depressed by their primary care physician. Women were found to have more depressive symptoms as self-reported on the Beck Depression Inventory (BDI). Women having high BDI scores (reflecting significant depression) were more likely than men with high BDI scores to be diagnosed by their primary care physician (p = 0.0295). Female patients made significantly more visits to the clinic than men. For both sexes, patients with greater numbers of primary care clinic visits were more likely to be diagnosed as depressed. Logistic regression revealed that gender has both a direct and indirect (through increased use) effect on the likelihood of being diagnosed as depressed. Patient BDI score, clinic use, educational level, and marital status were all significantly related to the diagnosis of depression. Controlling all other independent variables, women were 72% more likely than men to be identified as depressed, but this effect did not achieve statistical significance (p = 0.0981). In gender-specific analyses, BDI and clinic use were again significantly related to the diagnosis of depression for both sexes. However, educational and marital status predicted depression diagnosis only for women. Separated, divorced, or widowed women were almost five times as likely to be diagnosed as depressed as those who were never married, all other factors being equal. Clinic use and BDI scores were found to be important correlates of the diagnosis of depression. There was some evidence of possible gender bias in the diagnosis of depression. [ABSTRACT FROM AUTHOR]

Abstract--Results based on pooled time series and cross section data are presented, which indicate that state and local tax increases significantly retard economic growth when the revenue is used to fund transfer payments. However, when the revenue is used instead to finance improved public services (such as education, highways, and public health and safety) the favorable impact on location and production decisions provided by the enhanced services may more than counterbalance the disincentive effects of the associated taxes. These findings underscore the importance of considering the incentives provided by a state's expenditures as well as by its taxes. [ABSTRACT FROM AUTHOR]

This paper presents a simple computational procedure for determining a consumer's willingness to pay to have a price stabilization policy implemented. Numerical simulations are then provided which demonstrate that the commonly used expected surplus measures (whether Hicksian or Marshallian) can in fact seriously misstate the true benefits of price stabilization. These simulations also illustrate the extent to which the results may be dependent upon the assumptions made--implicitly or explicitly--regarding the consumer's attitudes toward risk, thereby underscoring the need to conduct sensitivity analyses to determine the robustness of cost-benefit assessments with respect to these assumptions. [ABSTRACT FROM AUTHOR]

Relates the literary history of the `Prostitute Priestess.' Piot's 1956 translation of `The Orator'; An analogue to Shakespeare's `Pericles'; The Senecan rhetoric of rape; Patriarchal structures of Mytilene.

Examines problems of assessing welfare effects of price stabilization by calculating the expected compensating variation of price change. Need for a set of restrictions on the utility function for expected compensating variation to be a valid measure; Significance of measuring ex-ante compensating variation for generating rigorous qualitative and quantitative assessments consistent with expected utility theory.

A theory of Markov processes for which the sample paths have random starting and terminal times was first considered by Hunt [4, 5]. Such processes require that the classical notion of a probability measure space be modified so as to allow σ-finite probability measures. Such an extension necessitates only minor adjustments of the language of probability theory; e.g., the phrase 'absolute probability of an event E' does not admit the usual interpretation and is not used. Only conditional probabilities are used in the extended theory and do admit the usual interpretation. The purpose of this paper is to establish regularity properties of Markov processes having sample paths with random creation and terminal times. An existence theorem for such processes appears in [3]. [ABSTRACT FROM AUTHOR]