More than half of substance abusers entering addiction treatment report a history of physical or ... more More than half of substance abusers entering addiction treatment report a history of physical or sexual abuse. It is unclear if such a history impacts treatment outcomes. This one-year follow-up study of 700 substance abusers sought to clarify the relationship between lifetime physical and/or sexual abuse and addiction treatment outcome to help address the specific needs of this population. To achieve this goal, baseline characteristics, no-show for treatment status, post-treatment clinical outcomes, and treatment history were studied for subjects with lifetime history of abuse (47.3%) versus without. Abused subjects, predominantly women, were significantly more impaired at baseline on clinical dimensions including family/social severity and psychiatric severity as measured by the Addiction Severity Index (ASI), and general level of functioning. The two groups endorsed different drugs as primary, with the abused group less frequently endorsing heroin and cocaine in favor of alcohol and polydrug use. Abused subjects reported more prior medical and psychiatric treatments. Abuse history was not a predictor of no-show for treatment. Over the 1-year follow-up, lifetime physical and/or sexual abuse was significantly associated with worse psychiatric status and more psychiatric hospitalizations and outpatient treatment despite receiving similar intensive addiction treatment.
: Mismatched placement, according to the American Society of Addiction Medicine&a... more : Mismatched placement, according to the American Society of Addiction Medicine's (ASAM) Patient Placement Criteria (PPC), promotes no-shows to treatment; however, little is known about the impact on patients with psychiatrically comorbid substance use disorder. : In a multisite trial, public-sector treatment-seeking adults (N = 700), following a computer-assisted ASAM PPC-1 structured interview, were blindly scored and randomly assigned to Level-of-Care (LOC)-II (intensive outpatient) or LOC-III (residential) settings. Patients scored as needing LOC-II but assigned to LOC-III were, by definition, "overmatched." : Among 143 overmatched patients, no-shows were significantly higher in comorbids versus noncomorbids (54% versus 28%; P < 0.01). Among overmatched comorbids, patients who no-showed compared with patients who showed were more likely to be females (70.4% versus 34.8%; P < 0.05), to have anxiety (63% versus 17.4%; P < 0.01), or have supportive family/social environments (81.5% versus 34.8%; P < 0.01). : The data support the validity of the PPC for matching comorbid patients. Mismatching increases no-show rates in general with undermatching, but it does so in particular with overmatching in patients with comorbid psychiatric symptomatology. Comorbidity interacts with gender, overmatched status, presence of anxiety, and supportive environment as predictors of treatment no-shows (odds ratios = 2.69, P < 0.05; 3.27, P < 0.05; 5.32, P < 0.001; and 3.12, P < 0.05, respectively).
We present the application of wavefront sensing to three-component, three-dimensional micro parti... more We present the application of wavefront sensing to three-component, three-dimensional micro particle tracking velocimetry (μPTV). The technique is based upon examining the defocus of the wavefront scattered by a tracer particle and from such information establishing the 3-D tracer location. The imaging system incorporates a cylindrical lens acting as an anamorphic element that creates different magnifications in the two orthogonal axes. A single anamorphic image is obtained from each tracer, which contains sufficient information to reconstruct the wavefront defocus and uniquely identify the tracer’s axial position. A mathematical model of the optical system is developed and shows that the lateral and depth performance of the sensor can be largely independently varied across a wide range. Hence, 3-D image resolution can be achieved from a single viewpoint, using simple and inexpensive optics and applied to a wide variety of microfluidic or biological systems. Our initial results show that an uncertainty in depth of 0.18 μm was achieved over a 20-μm range. The technique was employed to measure the 3-D velocity field of micron-sized fluorescent tracers in a flow within a micro channel, and an uncertainty of 2.8 μm was obtained in the axial direction over a range of 500 μm. The experimental results were in agreement with the expected fluid flow when compared to the corresponding CFD model. Thus, wavefront sensing proved to be an effective approach to obtain quantitative measurements of three-component three-dimensional flows in microfluidic devices.
This paper was motivated by the need for improved instrumentation to study mixing processes in mu... more This paper was motivated by the need for improved instrumentation to study mixing processes in multi-constituent and multi-phase fluid systems. The development of a single colour camera PIV system that can image micron size spectrally distinct fluorescent droplets in a multi-constituent gas phase flow is reported. Concentrations of fluorescent dyes in solution have been optimised to achieve sufficient fluorescence visibility. The adopted philosophy is to exploit the inherent co-registration offered by a 3-chip colour CCD camera with the images recorded in the three colour planes enabling flow constituent/phase to be determined as well as pulse order. The results show that the spectral discrimination process is robust and in a well mixed gas-phase flow the average error between the flow velocities in the two constituents is <4%. The use of UV excitation (on suitably excitable dyes) has the added benefit of spectrally separating the excitation wavelength from the imaging bandwidth to allow ‘flare removal’.
This paper was motivated by the need for improved instrumentation to study mixing processes in mu... more This paper was motivated by the need for improved instrumentation to study mixing processes in multi-constituent and multi-phase fluid systems. The development of a single colour camera PIV system that can image micron size spectrally distinct fluorescent droplets in a multi-constituent gas phase flow is reported. Concentrations of fluorescent dyes in solution have been optimised to achieve sufficient fluorescence visibility. The adopted philosophy is to exploit the inherent co-registration offered by a 3-chip colour CCD camera with the images recorded in the three colour planes enabling flow constituent/phase to be determined as well as pulse order. The results show that the spectral discrimination process is robust and in a well mixed gas-phase flow the average error between the flow velocities in the two constituents is <4%. The use of UV excitation (on suitably excitable dyes) has the added benefit of spectrally separating the excitation wavelength from the imaging bandwidth to allow ‘flare removal’.
We present the application of wavefront sensing to particle image velocimetry for three-component... more We present the application of wavefront sensing to particle image velocimetry for three-component (3C), three-dimensional (3D) flow measurement from a single view. The technique is based upon measuring the wavefront scattered by a tracer particle and from that wavefront the 3D tracer location can be determined. Hence, from a temporally resolved sequence of 3D particle locations the velocity vector field is obtained. Two approaches to capture the data required to measure the wavefronts are described: multi-planar imaging using a distorted diffraction grating and an anamorphic technique. Both techniques are optically efficient, robust and compatible with coherent and incoherent scattering from flow tracers. The depth (range) resolution and repeatability have been quantified experimentally using a single mode fiber source representing a tracer particle. The anamorphic approach is shown to have the greatest measurement range and hence was selected for the first proof of principle experiments using this technique for 3D particle imaging velocimetry (PIV) on a sparsely seeded gas phase flow.
Autoregulation mechanisms maintain blood flow approximately stable despite changes in arterial bl... more Autoregulation mechanisms maintain blood flow approximately stable despite changes in arterial blood pressure. A model that characterizes this system is of great use not only in understanding cerebral hemodynamics but also for the quantitative assessment of function/impairment of autoregulation. Using arterial blood pressure (ABP) as input and cerebral blood flow velocity (CBFV) as output, the autoregulatory mechanism was modeled using only spontaneous variability in both signals, in accordance with previous work. In this study a non-linear approach, based on a cascade, also known as block structure models, is presented, whose parameters are estimated by Differential Evolution. The results were compared with other linear and non-linear approaches previously used to model cerebral autoregulation. The performance of each model was assessed by the model’s predicted CBFV in terms of the normalized mean square error (NMSE) and the correlation coefficient. The results show that for relatively short signals (150 sec) containing only spontaneous fluctuations, cascade models performed better than a frequency domain method but are not significantly different from linear time-domain techniques tested. These results also show that slightly better performance can be obtained with the cascade models compared with more complicated non-linear models with the advantage of having more easily interpretable parameters and a simpler structure that facilitates their use in diagnostic methods.
Two-and three-component multi-phase air/fuel measurements have been performed on a GDI injector. ... more Two-and three-component multi-phase air/fuel measurements have been performed on a GDI injector. UV-excitable fluorescent tracers have been used to seed the gas phase, and the naturally occurring droplets in the fuel are the other phase. A high-pressure multi-hole GDI injector was mounted in a rig with a glass barrel to simulate the engine cylinder and provide optical access. Images were obtained under controlled conditions of fuel pressure and injection duration. Flow phase and pulse order have been determined from a single 3CCD colour camera. Suitable corrective processes have been adapted and implemented to account for crosstalk and chromatic aberrations so that the uncertainty of the velocity vectors produced is comparable to that of conventional PIV using 532 nm illumination. Multi-phase air/fuel vector maps have been produced. A second colour camera has been added to obtain stereo velocity measurements providing previously unavailable simultaneous information on the multi-phase (fuel/air) interaction with three velocity components.
We propose an annular-aperture-based defocusing technique for three-dimensional (3D) particle met... more We propose an annular-aperture-based defocusing technique for three-dimensional (3D) particle metrology from a single camera view. This simple configuration has high optical efficiency and the ability to deal with overlapped defocused images. Initial results show that an uncertainty in depth of 23 m can be achieved over a range of 10 mm for macroscopic systems. This method can also be applied in microscopy for the measurement of fluorescently doped microparticles, thus providing a promising solution for 3D flow metrology at both macroscales and microscales.
Este libro se escribió con el fin de presentar las estrategias que empleadas por el Estado para d... more Este libro se escribió con el fin de presentar las estrategias que empleadas por el Estado para dirigir y controlar las fuerzas del mercado financiero. Éstas se analizan una a una, desde 1923, con ocasión de la crisis del Banco López, hasta nuestros días con el tema de los modelos de administración del riesgo financiero. Es un texto de consulta
... La mayor contribución de Heller radica en la presentación de un modelo consistente para elcál... more ... La mayor contribución de Heller radica en la presentación de un modelo consistente para elcálculo de las reservas internacionales óptimas, relacionando tres aspectos fundamentales: El costo y la probabilidad de ajuste a un desequilibrio externo y el costo de mantener ...
Dominio español:En el siglo XVI, Chilpancingo era un pueblo indígena habitado por 102 familias y ... more Dominio español:En el siglo XVI, Chilpancingo era un pueblo indígena habitado por 102 familias y dependía de Zumpango en el aspecto civil y en el eclesiástico. Ubicado en el camino Acapulco -México, era un sitio de remuda, alimentación y alojamiento de los arrieros y comerciantes que transitaban con motivo de la llegada de la Nao de Filipinas. Dicha situación favoreció a los nativos del lugar quienes, gracias a sus servicios, alcanzaron varios privilegios vedados a otros pueblos indígenas, tales como tener caballos, vestir como españoles y no prestar servicios comunales. Propició, asimismo, el crecimiento de la población que rebasó la de los lugares vecinos y proveyó de mayores ingresos a sus habitantes.
More than half of substance abusers entering addiction treatment report a history of physical or ... more More than half of substance abusers entering addiction treatment report a history of physical or sexual abuse. It is unclear if such a history impacts treatment outcomes. This one-year follow-up study of 700 substance abusers sought to clarify the relationship between lifetime physical and/or sexual abuse and addiction treatment outcome to help address the specific needs of this population. To achieve this goal, baseline characteristics, no-show for treatment status, post-treatment clinical outcomes, and treatment history were studied for subjects with lifetime history of abuse (47.3%) versus without. Abused subjects, predominantly women, were significantly more impaired at baseline on clinical dimensions including family/social severity and psychiatric severity as measured by the Addiction Severity Index (ASI), and general level of functioning. The two groups endorsed different drugs as primary, with the abused group less frequently endorsing heroin and cocaine in favor of alcohol and polydrug use. Abused subjects reported more prior medical and psychiatric treatments. Abuse history was not a predictor of no-show for treatment. Over the 1-year follow-up, lifetime physical and/or sexual abuse was significantly associated with worse psychiatric status and more psychiatric hospitalizations and outpatient treatment despite receiving similar intensive addiction treatment.
: Mismatched placement, according to the American Society of Addiction Medicine&amp;amp;amp;a... more : Mismatched placement, according to the American Society of Addiction Medicine&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;#39;s (ASAM) Patient Placement Criteria (PPC), promotes no-shows to treatment; however, little is known about the impact on patients with psychiatrically comorbid substance use disorder. : In a multisite trial, public-sector treatment-seeking adults (N = 700), following a computer-assisted ASAM PPC-1 structured interview, were blindly scored and randomly assigned to Level-of-Care (LOC)-II (intensive outpatient) or LOC-III (residential) settings. Patients scored as needing LOC-II but assigned to LOC-III were, by definition, &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;quot;overmatched.&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;quot; : Among 143 overmatched patients, no-shows were significantly higher in comorbids versus noncomorbids (54% versus 28%; P &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;lt; 0.01). Among overmatched comorbids, patients who no-showed compared with patients who showed were more likely to be females (70.4% versus 34.8%; P &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;lt; 0.05), to have anxiety (63% versus 17.4%; P &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;lt; 0.01), or have supportive family/social environments (81.5% versus 34.8%; P &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;lt; 0.01). : The data support the validity of the PPC for matching comorbid patients. Mismatching increases no-show rates in general with undermatching, but it does so in particular with overmatching in patients with comorbid psychiatric symptomatology. Comorbidity interacts with gender, overmatched status, presence of anxiety, and supportive environment as predictors of treatment no-shows (odds ratios = 2.69, P &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;lt; 0.05; 3.27, P &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;lt; 0.05; 5.32, P &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;lt; 0.001; and 3.12, P &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;lt; 0.05, respectively).
We present the application of wavefront sensing to three-component, three-dimensional micro parti... more We present the application of wavefront sensing to three-component, three-dimensional micro particle tracking velocimetry (μPTV). The technique is based upon examining the defocus of the wavefront scattered by a tracer particle and from such information establishing the 3-D tracer location. The imaging system incorporates a cylindrical lens acting as an anamorphic element that creates different magnifications in the two orthogonal axes. A single anamorphic image is obtained from each tracer, which contains sufficient information to reconstruct the wavefront defocus and uniquely identify the tracer’s axial position. A mathematical model of the optical system is developed and shows that the lateral and depth performance of the sensor can be largely independently varied across a wide range. Hence, 3-D image resolution can be achieved from a single viewpoint, using simple and inexpensive optics and applied to a wide variety of microfluidic or biological systems. Our initial results show that an uncertainty in depth of 0.18 μm was achieved over a 20-μm range. The technique was employed to measure the 3-D velocity field of micron-sized fluorescent tracers in a flow within a micro channel, and an uncertainty of 2.8 μm was obtained in the axial direction over a range of 500 μm. The experimental results were in agreement with the expected fluid flow when compared to the corresponding CFD model. Thus, wavefront sensing proved to be an effective approach to obtain quantitative measurements of three-component three-dimensional flows in microfluidic devices.
This paper was motivated by the need for improved instrumentation to study mixing processes in mu... more This paper was motivated by the need for improved instrumentation to study mixing processes in multi-constituent and multi-phase fluid systems. The development of a single colour camera PIV system that can image micron size spectrally distinct fluorescent droplets in a multi-constituent gas phase flow is reported. Concentrations of fluorescent dyes in solution have been optimised to achieve sufficient fluorescence visibility. The adopted philosophy is to exploit the inherent co-registration offered by a 3-chip colour CCD camera with the images recorded in the three colour planes enabling flow constituent/phase to be determined as well as pulse order. The results show that the spectral discrimination process is robust and in a well mixed gas-phase flow the average error between the flow velocities in the two constituents is <4%. The use of UV excitation (on suitably excitable dyes) has the added benefit of spectrally separating the excitation wavelength from the imaging bandwidth to allow ‘flare removal’.
This paper was motivated by the need for improved instrumentation to study mixing processes in mu... more This paper was motivated by the need for improved instrumentation to study mixing processes in multi-constituent and multi-phase fluid systems. The development of a single colour camera PIV system that can image micron size spectrally distinct fluorescent droplets in a multi-constituent gas phase flow is reported. Concentrations of fluorescent dyes in solution have been optimised to achieve sufficient fluorescence visibility. The adopted philosophy is to exploit the inherent co-registration offered by a 3-chip colour CCD camera with the images recorded in the three colour planes enabling flow constituent/phase to be determined as well as pulse order. The results show that the spectral discrimination process is robust and in a well mixed gas-phase flow the average error between the flow velocities in the two constituents is <4%. The use of UV excitation (on suitably excitable dyes) has the added benefit of spectrally separating the excitation wavelength from the imaging bandwidth to allow ‘flare removal’.
We present the application of wavefront sensing to particle image velocimetry for three-component... more We present the application of wavefront sensing to particle image velocimetry for three-component (3C), three-dimensional (3D) flow measurement from a single view. The technique is based upon measuring the wavefront scattered by a tracer particle and from that wavefront the 3D tracer location can be determined. Hence, from a temporally resolved sequence of 3D particle locations the velocity vector field is obtained. Two approaches to capture the data required to measure the wavefronts are described: multi-planar imaging using a distorted diffraction grating and an anamorphic technique. Both techniques are optically efficient, robust and compatible with coherent and incoherent scattering from flow tracers. The depth (range) resolution and repeatability have been quantified experimentally using a single mode fiber source representing a tracer particle. The anamorphic approach is shown to have the greatest measurement range and hence was selected for the first proof of principle experiments using this technique for 3D particle imaging velocimetry (PIV) on a sparsely seeded gas phase flow.
Autoregulation mechanisms maintain blood flow approximately stable despite changes in arterial bl... more Autoregulation mechanisms maintain blood flow approximately stable despite changes in arterial blood pressure. A model that characterizes this system is of great use not only in understanding cerebral hemodynamics but also for the quantitative assessment of function/impairment of autoregulation. Using arterial blood pressure (ABP) as input and cerebral blood flow velocity (CBFV) as output, the autoregulatory mechanism was modeled using only spontaneous variability in both signals, in accordance with previous work. In this study a non-linear approach, based on a cascade, also known as block structure models, is presented, whose parameters are estimated by Differential Evolution. The results were compared with other linear and non-linear approaches previously used to model cerebral autoregulation. The performance of each model was assessed by the model’s predicted CBFV in terms of the normalized mean square error (NMSE) and the correlation coefficient. The results show that for relatively short signals (150 sec) containing only spontaneous fluctuations, cascade models performed better than a frequency domain method but are not significantly different from linear time-domain techniques tested. These results also show that slightly better performance can be obtained with the cascade models compared with more complicated non-linear models with the advantage of having more easily interpretable parameters and a simpler structure that facilitates their use in diagnostic methods.
Two-and three-component multi-phase air/fuel measurements have been performed on a GDI injector. ... more Two-and three-component multi-phase air/fuel measurements have been performed on a GDI injector. UV-excitable fluorescent tracers have been used to seed the gas phase, and the naturally occurring droplets in the fuel are the other phase. A high-pressure multi-hole GDI injector was mounted in a rig with a glass barrel to simulate the engine cylinder and provide optical access. Images were obtained under controlled conditions of fuel pressure and injection duration. Flow phase and pulse order have been determined from a single 3CCD colour camera. Suitable corrective processes have been adapted and implemented to account for crosstalk and chromatic aberrations so that the uncertainty of the velocity vectors produced is comparable to that of conventional PIV using 532 nm illumination. Multi-phase air/fuel vector maps have been produced. A second colour camera has been added to obtain stereo velocity measurements providing previously unavailable simultaneous information on the multi-phase (fuel/air) interaction with three velocity components.
We propose an annular-aperture-based defocusing technique for three-dimensional (3D) particle met... more We propose an annular-aperture-based defocusing technique for three-dimensional (3D) particle metrology from a single camera view. This simple configuration has high optical efficiency and the ability to deal with overlapped defocused images. Initial results show that an uncertainty in depth of 23 m can be achieved over a range of 10 mm for macroscopic systems. This method can also be applied in microscopy for the measurement of fluorescently doped microparticles, thus providing a promising solution for 3D flow metrology at both macroscales and microscales.
Este libro se escribió con el fin de presentar las estrategias que empleadas por el Estado para d... more Este libro se escribió con el fin de presentar las estrategias que empleadas por el Estado para dirigir y controlar las fuerzas del mercado financiero. Éstas se analizan una a una, desde 1923, con ocasión de la crisis del Banco López, hasta nuestros días con el tema de los modelos de administración del riesgo financiero. Es un texto de consulta
... La mayor contribución de Heller radica en la presentación de un modelo consistente para elcál... more ... La mayor contribución de Heller radica en la presentación de un modelo consistente para elcálculo de las reservas internacionales óptimas, relacionando tres aspectos fundamentales: El costo y la probabilidad de ajuste a un desequilibrio externo y el costo de mantener ...
Dominio español:En el siglo XVI, Chilpancingo era un pueblo indígena habitado por 102 familias y ... more Dominio español:En el siglo XVI, Chilpancingo era un pueblo indígena habitado por 102 familias y dependía de Zumpango en el aspecto civil y en el eclesiástico. Ubicado en el camino Acapulco -México, era un sitio de remuda, alimentación y alojamiento de los arrieros y comerciantes que transitaban con motivo de la llegada de la Nao de Filipinas. Dicha situación favoreció a los nativos del lugar quienes, gracias a sus servicios, alcanzaron varios privilegios vedados a otros pueblos indígenas, tales como tener caballos, vestir como españoles y no prestar servicios comunales. Propició, asimismo, el crecimiento de la población que rebasó la de los lugares vecinos y proveyó de mayores ingresos a sus habitantes.
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