Design of a 3000-Pixel Transition-Edge Sensor X-Ray Spectrometer for Microcircuit Tomography.

Feature sizes in integrated circuits have decreased substantially over time, and it has become increasingly difficult to three-dimensionally image these complex circuits after fabrication. This can be important for process development, defect analysis, and detection of unexpected structures in externally sourced chips, among other applications. Here, we report on a non-destructive, tabletop approach that addresses this imaging problem through x-ray tomography, which we uniquely realize with an instrument that combines a scanning electron microscope (SEM) with a transition-edge sensor (TES) x-ray spectrometer. Our approach uses the highly focused SEM electron beam to generate a small x-ray generation region in a carefully designed target layer that is placed over the sample being tested. With the high collection efficiency and resolving power of a TES spectrometer, we can isolate x-rays generated in the target from background and trace their paths through regions of interest in the sample layers, providing information about the various materials along the x-ray paths through their attenuation functions. We have recently demonstrated our approach using a 240 Mo/Cu bilayer TES prototype instrument on a simplified test sample containing features with sizes of ∼ 1 µm. Currently, we are designing and building a 3000 Mo/Au bilayer TES spectrometer upgrade, which is expected to improve the imaging speed by factor of up to 60 through a combination of increased detector number and detector speed.

Validating the Persian Intuitive Eating Scale-2 Among Breast Cancer Survivors Who Are Overweight/Obese.

Women with breast cancer are at risk of being overweight/obese which may consequently increase mortality. Intuitive eating is an adaptive eating behavior which might be beneficial for weight outcomes. The present study validated the Persian Intuitive Eating Scale-2 (IES-2) among overweight/obese Iranian females with breast cancer. Women who were overweight/obese with breast cancer (n = 762; mean ± SD age = 55.1 ± 5.7 years) completed the following questionnaires: IES-2, General Self-Efficacy Scale (GSE-6), Hospital Anxiety and Depression Scale (HADS), Short Form-12 (SF-12), Weight Bias Internalization Scale (WBIS), Body Appreciation Scale-2 (BAS-2), and Eating Attitudes Test (EAT-26). Confirmatory factor analysis (CFA) and Rasch analysis were applied to examine the psychometric properties of the IES-2. Associations between IES-2 score and other scale scores were assessed. CFA and Rasch analysis suggested that the Persian IES-2 had robust psychometric properties and all IES-2 items were meaningful in their embedded domains. The four-factor structure of the Persian IES-2 was confirmed. Concurrent validity was supported by the positive correlations between the IES-2 score and scores on the GSE-6, SF-12 mental component, and BAS-2. Negative correlations were found between the IES-2 score and the HADS (anxiety and depression subscales), WBIS, and EAT-26. The present study demonstrated that the Persian IES-2 is a well-designed instrument and is applicable for women who are overweight/obese with breast cancer.

Rasch Analysis for Instrument Development: Why, When, and How?

This essay describes Rasch analysis psychometric techniques and how such techniques can be used by life sciences education researchers to guide the development and use of surveys and tests. Specifically, Rasch techniques can be used to document and evaluate the measurement functioning of such instruments. Rasch techniques also allow researchers to construct "Wright maps" to explain the meaning of a test score or survey score and develop alternative forms of tests and surveys. Rasch techniques provide a mechanism by which the quality of life sciences-related tests and surveys can be optimized and the techniques can be used to provide a context (e.g., what topics a student has mastered) when explaining test and survey results.