Teaching the History of Black Women: A Bibliographical Essay

The following article originally appeared in The History Teacher 13 (February 1980) and is reprinted here be permission. During the latter part of the 1970s, students of American history have recognized that black women\u27s unique history cannot be thoroughly analyzed within the confines of either black history or women\u27s history. Unfortunately, a gap exists between the realization of the goal to correct the problem and the publication of secondary works on black women\u27s history. To date, only one anthology containing original essays treats black women\u27s experiences from an historical perspective: Sharon Harley and Rosalyn Terborg-Penn (eds.), The AfroAmerican Woman: Struggles and Images (Port Washington, N.Y.: Kennikat Press, 1978). This work is supplemented by two documentary collections, Gerda Lerner (ed.), Black Women in White America: A Documentary History (New York: Random House, 1972), and Bert James Loewenberg and Ruth Bogin (eds.), Black Women in Nineteenth Century American Life (University Park: Pennsylvania State University Press, 1976). The paucity of secondary books leaves teachers with the problem of locating sources to assist in curriculum expansion and revision. Although only a few books have recently appeared, there are numerous historical essays describing experiences of black women. In addition, there are several older, yet still quite relevant books and articles that can aid history teachers in integrating black women\u27s experiences into United States, women\u27s, and black history courses

Lens-free interferometric microscope for transparent materials

As health systems fight against epidemics and infectious diseases, new forms of diagnostics need to be developed in order to meet the growing demand for services, often in locations without the necessary infrastructure. An emerging solution to this problem is point of care (POC) devices since they can provide rapid diagnostics without the need for specialized personnel or complex infrastructures. In this thesis, we show the development of a POC platform for the rapid early detection of infection, in particular Sepsis, a whole-body inflammatory reaction with high mortality rates. The main components of this platform are: a lens-free interferometric microscope (LIM) and a microfluidic cartridge with a functionalized plasmonic chip for the label-free detection of biomarkers. The LIM is also able to measure the phase modulation in commercial plasmonic chips. More specifically the thesis describes: • The development of a LIM with a large field of view and depth of field showing a sensitivity of 1nm along the beam propagation axis, which allows, for instance, the measurements of ultra-thin (2nm thickness) transparent silica and protein monolayer microarrays. • The generation of periodic structured light beams, obtained using a simple configuration including the birefringent elements of the LIM. These can be applied not only to imaging and biomarker detection but also in additive manufacturing and micro-structuring of surfaces. • The phase measurement of commercial surface plasmon resonance chips for the detection of changes in the refractive index of liquids. The phase measurements provide a sensitivity for bulk refractive index changes that is about one order of magnitude larger than for intensity-based detection under similar conditions. These results show a potential enhancement of the sensitivity of standard systems used in the biomedical community. • The development of a POC device comprising the LIM as a reader of specifically designed plasmonic gold nanohole array chips. The reading of the phase signal in the LIM shows a sensitivity increased by one order of magnitude thanks to the enhanced localized surface plasmon resonance interaction. Low concentrations of proteins and bacteria (as low as a single unit) are detected in measurements that also include human samples. This platform has the potential to multiplex the signal for simultaneous detection of thousands or even millions of different biomarkers. The LIM presented in this thesis is a very sensitive and robust imaging system with a high performance level for the detection of small quantities of transparent materials, with applications in microscopy and biomedicine.A medida que los sistemas de salud combaten epidemias y enfermedades infecciosas, nuevas formas de diagnóstico deben desarrollarse para satisfacer la creciente demanda de servicios, a menudo en lugares sin la infraestructura necesaria. Una solución emergente a este problema son los dispositivos de punto de atención (POC por sus siglas en inglés) ya que pueden proporcionar un diagnóstico rápido sin la necesidad de personal especializado o infraestructura compleja. En esta tesis mostramos el desarrollo de una plataforma POC para la detección rápida y temprana de infecciones, en particular Sepsis, una reacción inflamatoria de todo el cuerpo con altas tasas de mortalidad. Los principales componentes de esta plataforma son: un microscopio interferométrico sin lentes (LIM por sus siglas en inglés) y un cartucho de microfluídica con un chip plasmónico funcionalizado para la detección de biomarcadores, libre de marcadores adicionales. El LIM es también capaz de medir la modulación de fase en chips plasmónicos comerciales. Más específicamente, la tesis describe: * El desarrollo del LIM con un gran campo de visión y profundidad de campo mostrando una sensibilidad de 1nm a lo largo del eje de propagación del haz, que permite, por ejemplo, las mediciones de microarreglos ultrafinos (grosor de 2nm) y transparentes de Sílica y de monocapas de proteína.* La generación de haces de luz estructurados periódicos, obtenidos usando una configuración simple que incluye los elementos birrefringentes del LIM. Estos pueden ser aplicados no sólo a la detección de imágenes y biomarcadores, sino también a la fabricación aditiva y microestructuración de superficies. * La medición de fase en chips comerciales por resonancia de plasmón superficial para la detección de cambios en el índice de refracción de líquidos. Las mediciones de fase proporcionan una sensibilidad para cambios de índice de refracción en bulto que es aproximadamente un orden de magnitud mayor que para la detección basada en la intensidad con condiciones similares. Estos resultados muestran una potencial mejora de la sensibilidad de los sistemas estándar utilizados en la comunidad biomédica. * El desarrollo de un dispositivo POC que comprende el LIM como lector de chips plasmónicos de oro con arreglos de nano-agujeros específicamente diseñados. La lectura de la señal de fase en el LIM muestra un aumento de un orden de magnitud en la sensibilidad gracias a la interacción mejorada por la resonancia de plasmón superficial localizado. Bajas concentraciones de proteínas y bacterias (tan bajas como una sola bacteria) se detectan en mediciones que también incluyen muestras humanas. Esta plataforma tiene el potencial de multiplexar la señal para la detección simultánea de miles o incluso millones de biomarcadores diferentes. El LIM presentado en esta tesis es un sistema de imagen muy sensible y robusto con un alto nivel de rendimiento para la detección de pequeñas cantidades de materiales transparentes, con aplicaciones en microscopía y biomedicina

Lens-free interferometric microscope for transparent materials

As health systems fight against epidemics and infectious diseases, new forms of diagnostics need to be developed in order to meet the growing demand for services, often in locations without the necessary infrastructure. An emerging solution to this problem is point of care (POC) devices since they can provide rapid diagnostics without the need for specialized personnel or complex infrastructures. In this thesis, we show the development of a POC platform for the rapid early detection of infection, in particular Sepsis, a whole-body inflammatory reaction with high mortality rates. The main components of this platform are: a lens-free interferometric microscope (LIM) and a microfluidic cartridge with a functionalized plasmonic chip for the label-free detection of biomarkers. The LIM is also able to measure the phase modulation in commercial plasmonic chips. More specifically the thesis describes: • The development of a LIM with a large field of view and depth of field showing a sensitivity of 1nm along the beam propagation axis, which allows, for instance, the measurements of ultra-thin (2nm thickness) transparent silica and protein monolayer microarrays. • The generation of periodic structured light beams, obtained using a simple configuration including the birefringent elements of the LIM. These can be applied not only to imaging and biomarker detection but also in additive manufacturing and micro-structuring of surfaces. • The phase measurement of commercial surface plasmon resonance chips for the detection of changes in the refractive index of liquids. The phase measurements provide a sensitivity for bulk refractive index changes that is about one order of magnitude larger than for intensity-based detection under similar conditions. These results show a potential enhancement of the sensitivity of standard systems used in the biomedical community. • The development of a POC device comprising the LIM as a reader of specifically designed plasmonic gold nanohole array chips. The reading of the phase signal in the LIM shows a sensitivity increased by one order of magnitude thanks to the enhanced localized surface plasmon resonance interaction. Low concentrations of proteins and bacteria (as low as a single unit) are detected in measurements that also include human samples. This platform has the potential to multiplex the signal for simultaneous detection of thousands or even millions of different biomarkers. The LIM presented in this thesis is a very sensitive and robust imaging system with a high performance level for the detection of small quantities of transparent materials, with applications in microscopy and biomedicine.A medida que los sistemas de salud combaten epidemias y enfermedades infecciosas, nuevas formas de diagnóstico deben desarrollarse para satisfacer la creciente demanda de servicios, a menudo en lugares sin la infraestructura necesaria. Una solución emergente a este problema son los dispositivos de punto de atención (POC por sus siglas en inglés) ya que pueden proporcionar un diagnóstico rápido sin la necesidad de personal especializado o infraestructura compleja. En esta tesis mostramos el desarrollo de una plataforma POC para la detección rápida y temprana de infecciones, en particular Sepsis, una reacción inflamatoria de todo el cuerpo con altas tasas de mortalidad. Los principales componentes de esta plataforma son: un microscopio interferométrico sin lentes (LIM por sus siglas en inglés) y un cartucho de microfluídica con un chip plasmónico funcionalizado para la detección de biomarcadores, libre de marcadores adicionales. El LIM es también capaz de medir la modulación de fase en chips plasmónicos comerciales. Más específicamente, la tesis describe: * El desarrollo del LIM con un gran campo de visión y profundidad de campo mostrando una sensibilidad de 1nm a lo largo del eje de propagación del haz, que permite, por ejemplo, las mediciones de microarreglos ultrafinos (grosor de 2nm) y transparentes de Sílica y de monocapas de proteína.* La generación de haces de luz estructurados periódicos, obtenidos usando una configuración simple que incluye los elementos birrefringentes del LIM. Estos pueden ser aplicados no sólo a la detección de imágenes y biomarcadores, sino también a la fabricación aditiva y microestructuración de superficies. * La medición de fase en chips comerciales por resonancia de plasmón superficial para la detección de cambios en el índice de refracción de líquidos. Las mediciones de fase proporcionan una sensibilidad para cambios de índice de refracción en bulto que es aproximadamente un orden de magnitud mayor que para la detección basada en la intensidad con condiciones similares. Estos resultados muestran una potencial mejora de la sensibilidad de los sistemas estándar utilizados en la comunidad biomédica. * El desarrollo de un dispositivo POC que comprende el LIM como lector de chips plasmónicos de oro con arreglos de nano-agujeros específicamente diseñados. La lectura de la señal de fase en el LIM muestra un aumento de un orden de magnitud en la sensibilidad gracias a la interacción mejorada por la resonancia de plasmón superficial localizado. Bajas concentraciones de proteínas y bacterias (tan bajas como una sola bacteria) se detectan en mediciones que también incluyen muestras humanas. Esta plataforma tiene el potencial de multiplexar la señal para la detección simultánea de miles o incluso millones de biomarcadores diferentes. El LIM presentado en esta tesis es un sistema de imagen muy sensible y robusto con un alto nivel de rendimiento para la detección de pequeñas cantidades de materiales transparentes, con aplicaciones en microscopía y biomedicina.Postprint (published version

Ultrasensitive interferometric on-chip microscopy of transparent objects

Light microscopes can detect objects through several physical processes, such as scattering, absorption, and reflection. In transparent objects, these mechanisms are often too weak, and interference effects are more suitable to observe the tiny refractive index variations that produce phase shifts. We propose an on-chip microscope design that exploits birefringence in an unconventional geometry. It makes use of two sheared and quasi-overlapped illuminating beams experiencing relative phase shifts when going through the object, and a complementary metal-oxide-semiconductor image sensor array to record the resulting interference pattern. Unlike conventional microscopes, the beams are unfocused, leading to a very large field of view (20 mm(2)) and detection volume (more than 0.5 cm(3)), at the expense of lateral resolution. The high axial sensitivity (<1 nm) achieved using a novel phase-shifting interferometric operation makes the proposed device ideal for examining transparent substrates and reading microarrays of biomarkers. This is demonstrated by detecting nanometer-thick surface modulations on glass and single and double protein layers.Peer ReviewedPostprint (published version

Technique for generating periodic structured light beams using birefringent elements

We put forward a simple, scalable and robust technique for generating periodically structured light beams with intensity patterns, e.g. of the form cos2n(kxx) cos2m(kyy), where kx and ky are real numbers that can be tailored and n and m are integers. The technique combines the use of Gaussian beams with curved wavefronts, birefringent crystals (Savart plates) and linear polarizers. Applications range from photolithography to fabrication of micro-lens array and fiber Bragg gratings, 3D printing and tailoring of optical lattices for trapping atoms and molecules.Peer ReviewedPostprint (published version

La "ecología de presiones" en el desplazamiento de las lenguas indígenas por el español. Presentación de un modelo

In einer mehrsprachigen Gesellschaft, wie der mexikanischen, wird ständig Druck auf die unterschiedlichen indigenen Sprachen ausgeübt, in dessen Folge die indigene Sprache durch das Spanische verdrängt werden kann. Das ist immer dann der Fall, wenn die existierende Sprachökologie (MÜHLHÄUSLER 1996) an Stabilität verliert. In diesem Beitrag wird ein Modell vorgestellt, dass die Ursachen des Drucks erklärt, der auf den Schwund oder den Erhalt einer indigenen Sprache einwirken kann. Da es sich hierbei um unterschiedliche Druckebenen handelt, die auf eine gegebene Sprachökologie einwirken, nenne ich dieses Modell "Ökologie der Druckebenen". Diese Ökologie der Druckebenen kann sich, wie auch die Sprachökologie selbst, in einem mehr oder weniger stabilen Zustand befinden. Das Modell dient sowohl der Analyse von qualitativen als auch quantitativen Daten. Ich beabsichtige in diesem Beitrag nicht die Existenz des Sprachenschwunds einer bestimmten indigenen Sprache in Mexiko durch das Spanische anhand empirischer Daten nachzuweisen. Ziel des Beitrags ist vielmehr, das genannte Modell vorzustellen. Aus diesem Grund wird der Prozess, der den Konflikt zwischen den Druckebenen darstellt, nur anhand eines hypothetischen Falls erklärt. URN: urn:nbn:de:0114-fqs0604396Mexico represents a multilingual context in which certain pressures bring about a language shift among speakers of indigenous languages (IL) to speak Spanish. This occurs when the balance of "linguistic ecology" is disturbed (MÜHLHÄUSLER 1996). The purpose of this article is to present and demonstrate a model that helps to explain the origin of the different pressures that positively or negatively influence IL maintenance. I refer to this model as "the ecology of pressures" because it deals with pressures in a linguistic context, and these, the same as the languages, can be in a balanced or unbalanced relationship. This model can be used for either quantitative or qualitative analyses. I illustrate the dynamics of the different pressures by taking a hypothetical case in a situation of indigenous language shift by Spanish, without presenting empirical data. URN: urn:nbn:de:0114-fqs0604396En una situación multilingüe, como la de México, existen diferentes presiones que pesan sobre las lenguas indígenas para que éstas sean desplazadas por la lengua oficial, el español. Esto sucede cuando el equilibrio de la "ecología lingüística" (MÜHLHÄUSLER 1996) se ve afectado. El propósito de este artículo es presentar un modelo que explique el origen de las diferentes presiones que influyen a favor o en contra del mantenimiento de las lenguas indígenas. Lo denominaré "modelo de ecología de presiones" porque se trata de las presiones en una ecología lingüística, y éstas, igual que las lenguas, pueden estar en una relación equilibrada o desequilibrada. Dicho modelo servirá tanto para un análisis de datos cuantitativos como para un análisis cualitativo. Mi objetivo no es comprobar que el desplazamiento de la lengua indígena por el español está por concluirse, sino presentar el modelo y mostrar su funcionamiento. Ejemplificaré la dinámica de las diferentes presiones en conflicto tomando un caso hipotético en una situación de desplazamiento de la lengua indígena por el español, hecho por el cual no voy a presentar datos empíricos. URN: urn:nbn:de:0114-fqs060439

Determination of the effective detector area of an energy-dispersive X-ray spectrometer at the scanning electron microscope using experimental and theoretical X-ray emission yields

Dieser Beitrag ist mit Zustimmung des Rechteinhabers aufgrund einer (DFG geförderten) Allianz- bzw. Nationallizenz frei zugänglich.This publication is with permission of the rights owner freely accessible due to an Alliance licence and a national licence (funded by the DFG, German Research Foundation) respectively.A method is proposed to determine the effective detector area for energy-dispersive X-ray spectrometers (EDS). Nowadays, detectors are available for a wide range of nominal areas ranging from 10 up to 150 mm2. However, it remains in most cases unknown whether this nominal area coincides with the “net active sensor area” that should be given according to the related standard ISO 15632, or with any other area of the detector device. Moreover, the specific geometry of EDS installation may further reduce a given detector area. The proposed method can be applied to most scanning electron microscope/EDS configurations. The basic idea consists in a comparison of the measured count rate with the count rate resulting from known X-ray yields of copper, titanium, or silicon. The method was successfully tested on three detectors with known effective area and applied further to seven spectrometers from different manufacturers. In most cases the method gave an effective area smaller than the area given in the detector description

Assessment of the Pseudo Geostationary Lightning Mapper Products at the Spring Program and Summer Experiment

Since 2010, the de facto Geostationary Lightning Mapper (GLM) demonstration product has been the PseudoGeostationary Lightning Mapper (PGLM) product suite. Originally prepared for the Hazardous Weather Testbed's Spring Program (specifically the Experimental Warning Program) when only four groundbased lightning mapping arrays were available, the effort now spans collaborations with several institutions and eight collaborative networks. For 2013, NASA's Shortterm Prediction Research and Transition (SPoRT) Center and NOAA's National Severe Storms Laboratory have worked to collaborate with each network to obtain data in realtime. This has gone into producing the SPoRT variant of the PGLM that was demonstrated in AWIPS II for the 2013 Spring Program. Alongside the PGLM products, the SPoRT / Meteorological Development Laboratory's total lightning tracking tool also was evaluated to assess not just another visualization of future GLM data but how to best extract more information while in the operational environment. Specifically, this tool addressed the leading request by forecasters during evaluations; provide a time series trend of total lightning in realtime. In addition to the Spring Program, SPoRT is providing the PGLM "mosaic" to the Aviation Weather Center (AWC) and Storm Prediction Center. This is the same as what is used at the Hazardous Weather Testbed, but combines all available networks into one display for use at the national centers. This year, the mosaic was evaluated during the AWC's Summer Experiment. An important distinction between this and the Spring Program is that the Summer Experiment focuses on the national center perspective and not at the local forecast office level. Specifically, the Summer Experiment focuses on aviation needs and concerns and brings together operational forecaster, developers, and FAA representatives. This presentation will focus on the evaluation of SPoRT's pseudoGLM products in these separate test beds. The emphasis will be on how future GLM observations can support operations at both the local and national scale and how the PGLM was used in combination with other lightning data sets. Evaluations for the PGLM were quite favorable with forecasters appreciating the high temporal resolution, the ability to look for rapid increases in lightning activity ahead of severe weather, as well as situational awareness for where convection is firing and for flight routing

A dynamic theory of personality and emotions

This dissertation presents a dynamic theory of personality and emotions. The theory offered is explicit in its incorporation of an evolutionary-functionalist perspective and suggests that personality and the emotions are dynamic within the limits imposed by the functions of each. The dissertation begins by discussing the ubiquity of goals and goal-organising constructs in living systems. Personality, it is argued, is most validly conceptualised as being a complex goal-organising construct. Specific attention is then given to the consideration of innate motives in a motivational model of personality, the process by which innate motives become representational goals the place of emotions in the elaboration of innate motives, and the place of consciousness in goal, developmental and emotion processes. Following this, a functional conceptualisation of emotions and conscious emotional experience consistent with the motivational model of personality is developed. Empirical attention is devoted to the relationships between goals and emotions, the nature and measurement of conscious emotional experience, and the place of emotion in generating adaptive behaviour. Overall, the dissertation suggests that emotions and personality are necessarily related phenomena, each contributing to, and reflecting the other in the process of human striving