1,249 research outputs found
The Family History of Cristhian Guzman
No full textCristhian Guzman authored this family history as part of the course requirements for Your Family in History: HIST 550/700 offered online in Spring 2019 and was submitted to the Pittsburg State University Digital Commons. Please contact the author directly with any questions or comments: [email protected]
Experimental application of a dynamic observer to capture and predict the dynamics of a flat-plate boundary layer
No full textThe recent approach, proposed by Guzman-Inigo et al. \cite{GuzmanInigo2014}, using System Identification to derive a Reduced Order Model from snapshots of a flow is applied to a transitional boundary layer growing over a flat-plate. It is shown that such an approach can indeed be applied to experimental PIV snapshots. Using a proper learning dataset and a proper local sensor, it is shown that the evolution of boundary layer can be properly estimated from the time evolution of the local probe and with no more than ten POD modes for the Reduced Order Model. The influence of the various parameters on the efficiency of the system identification technique is discussed
Learning needs assessment examining current infection prevention and control knowledge, readiness, and training preferences among healthcare providers
No full textNicholas Ida, MPH; Judith A. Guzman Cottrill, DO; Roza Tammer, MPH, CIC; Rebecca Pierce, PhD, MS, BSN; Dat Tran, MD, MS.This archived document is maintained by the State Library of Oregon as part of the Oregon Documents Depository Program. It is for informational purposes and may not be suitable for legal purposes.Mode of access: Internet from the Oregon Government Publications Collection.Text in English
Double-directional Multipath Data at 140 GHz
No full textThis data set contains 140 GHz double-directional path data in an indoor hall environment. Details of the environment and data format are available in .txt and .ppt files in the same package as data. The data were derived from channel sounding along with a measurement-based ray-launcher, which is elaborated in the following paper.
M. F. de Guzman, P. Koivumäki and K. Haneda, "Double-directional multipath data at 140 GHz derived from measurement-based ray-tracer," in Proc. 2022 Vehicular Technology Conference, Helsinki, Finland, June 2022.
@INPROCEEDINGS{deGuzman22_VTCS,
author={de Guzman, Mar Francis and Koivum\"{a}ki, Pasi and Haneda, Katsuyuki},
booktitle={2022 95th Veh. Tech. Conf. (VTC2022-Spring)},
title={Double-directional multipath data at 140 {GHz} derived from measurement-based ray-launcher},
year={2022},
address={Helsinki, Finland},
month={June},
pages={1-6},
Are you sitting comfortably? The political economy of the body
No full textThe aim of this paper is to examine the relationship between the mass production of furniture in modern industrial societies and lower back pain (LBP). The latter has proven to be a major cost to health services and private industry throughout the industrialised world and now represents a global health issue as recent WHO reports on obesity and LBP reveal. Thus far there have been few co-ordinated attempts to deal with the causes of the problem through public policy. Drawing upon a range of sources in anthropology, health studies, politics and economics, the paper argues that this a modern social problem rooted in the contingent conjuncture of natural and social causal mechanisms. The key question it raises is: what are the appropriate mechanisms for addressing this problem? This paper develops an analysis rooted in libertarian social theory and argues that both the state and the capitalist market are flawed mechanisms for resolving this problem. There remains a fundamental dilemma for libertarians, however. Whilst the state and the market may well be flawed mechanisms, they are the dominant ones shaping global political economy. To what extent can libertarians work within these structures and remain committed to libertarian goals
Jesuit Higher Education
No full textThis article describes how the author designed a mediation course applying the Ignatian Pedagogical Paradigm (IPP). Examples are shared of some of the assignments and activities as well as narratives of students evidencing how by combining the five tenets of IPP -- context, experience, reflection, action, and evaluation -- students achieve professional, spiritual, and personal growth.148-63
Differentiation potential, lineage commitment and gene expression profile of human cortical neural progenitor cells derived from pluripotent stem cells
No full textThe human cerebral cortex is composed of the variety of neurons and glial cells that are organized into six different layers. During development, this complex structure originates from a simple neuroepithelium. As neurogenesis continues the neural stem and progenitor cells residing in the ventricular zone (VZ) and subventricular zone (SVZ), generate cortical projection neurons in an inside-out order. The neurons within each layer have particular functions, gene expression patterns and morphologies. These neurons are born at defined stages during development. The developmental mechanisms that regulate neural progenitor fate specification during cerebral cortex development remained elusive. Stem cell based systems allow at least partial recapitulation of the important aspects of human cortical neurogenesis in a simple and accessible cell culture manner. These systems have been successfully used to understand specific mechanisms associated with human cortical development and disorders.
Here, I studied the fate potential of human cortical neural progenitors derived from 2-dimensional (2D) in vitro corticogenesis. I also investigated how neural stem cells/progenitors generate the great diversity of neurons during in vitro cortical differentiation. I propose that fate potential of the neural progenitor (NP) pool changes during human cortical development. I employed retrovirus birth dating to investigate timing of neurogenesis. I found that not only is the early progenitor pool multipotent and generates both deep and upper layer neurons but also the late progenitors are capable to give rise to deep and upper layer neurons. It has been suggested that both intrinsic and extrinsic factors mediate fate specification of neural progenitors during development. I first tried to find the transcriptional program, which regulates the competence of NPCs during differentiation. I isolated the NPs based on CD184+, CD24+, CD271-, CD44- expression at sequential stages during in vitro corticogenesis and studied the transcriptional profile of these cells. The analysis confirmed the dynamic transcriptional program of NPs over the course of differentiation. Late sorted NPs give rise to more upper layer neurons and surprisingly to a high proportion of deep layer neurons in comparison to early progenitors. Moreover, NPs (isolated at early and late stages of differentiation) when co-cultured with the cells from different differentiation stage alter the proportions and types of generated neurons in response to environmental signals.
This thesis is organized in five chapters. The first chapter provides an introduction to early human cerebral cortex development as well as a summary of common strategies for in vitro cortical differentiation derived from human pluripotent stem cells (hPSCs). The chapter ends with the aims of the project. The second chapter contains the main results that are presented as a research manuscript. “Human pluripotent stem cell derived neural progenitors display two modes of neural fate determination”. Chapter two also includes my collaboration in a research project in our lab entitled “Neurodegeneration associated TDP-43 induces p53-mediated cell death of stem cells and neurons”
In chapter two I also present my result during collaboration in the project “Multigene delivery in primary and stem cells”. The two papers entitled “Highly efficient baculovirus-mediated multigene” and “Baculovirus-based genome editing in primary cells” are attached as an appendix. In Chapter three and four, I summarize and discussed our results and refer to the limitations of our system. Chapter five contains the detailed methods and protocols that have been used in the thesis.
Intraoperative hypothermia during vascular neurosurgical procedures
No full textIncreasing evidence in animal models and clinical trials for stroke, hypoxic encephalopathy for children, and traumatic brain injury have shown that mild hypothermia may attenuate ischemic damage and improve neurological outcome. However, it is less clear if mild intraoperative hypothermia during vascular neurosurgical procedures results in improved outcomes for patients. This review examines the scientific evidence behind hypothermia as a treatment and discusses factors that may be important for the use of this adjuvant technique, including cooling temperature, duration of hypothermia, and rate of rewarming
Investigation of intraoperative accelerometer data recording for safer and improved target selection for deep brain stimulation
No full textBackground: Deep Brain Stimulation (DBS) is a well established surgical treatment for Parkinson’s Disease (PD) and Essential Tremor (ET). Electrical leads are surgically implanted in the deeply seated structures in the brain and chronically stimulated. The location of the lead with respect to the anatomy is very important for optimal treatment. Therefore, clinicians carefully plan the surgery, record electrophysiological signals from the region of interest and perform stimulation tests to identify the best location to permanently place the leads. Nevertheless, there are certain aspects of the surgery that can still be improved. Firstly, therapeutic effects of stimulation are estimated by visually evaluating changes in tremor or passively moving patient's limb to evaluate changes in rigidity. These methods are subjective and depend heavily on the experience of the evaluator. Secondly, a significant amount of patient data is collected before and during the surgery like various CT and MR images, surgical planning information, electrophysiological recordings and results of stimulation tests. These are not fully utilized at the time of choosing the position for lead placement as they are either not available or acquired on separate systems or in the form of paper notes only. Thirdly, studies have shown that the current target structures to implant the leads (Subthalamic Nucleus (STN) for PD and Ventral Intermediate Nucleus (VIM) for ET) may not be the only ones responsible for the therapeutic effects. The objective of this doctoral work is to develop new methods that help clinicians subdue the above limitations which could in the long term improve the DBS therapy.
Method: After a thorough review of the existing literature, specifically customized solutions were designed for the shortcomings described above. A new method to quantitatively evaluate tremor during DBS surgery using acceleration sensor was developed. The method was then adapted to measure acceleration of passive movements and to evaluate changes in rigidity through it. Data from 30 DBS surgeries was collected by applying these methods in two clinical studies: one in Centre Hospitalier Universitaire, Clermont-Ferrand, France and another multi-center study in Universitäspital Basel and Inselspital Bern in Switzerland. To study the role of different anatomical structures in the therapeutic and adverse effects of stimulation, the data collected during the study was analysed using two methods. The first classical approach was to classify the data based on the anatomical structure in which the stimulating contact of the electrode was located. The second advanced approach was to use patient-specific Finite Element Method (FEM) simulations of the Electric Field (EF) to estimate the spatial distribution of stimulation in the structures surrounding the electrode. Such simulations of the adverse effect inducing stimulation current amplitudes are used to visualize the boundaries of safe stimulation and identify structures that could be responsible for these effects. In addition, the patient-specific simulations are also used to develop a new method called "Improvement Maps" to generate 2D and 3D visualization of intraoperative stimulation test results with the patient images and surgical planning. This visualization summarized the stimulation test results by dividing the explored area into multiple regions based on the improvement in symptoms as measured by the accelerometric methods.
Results: The accelerometric method successfully measured changes in tremor and rigidity. Standard deviation, signal energy and spectral amplitude of dominant frequency correlated with changes in the symptoms. Symptom suppressing stimulation current amplitudes identified through quantitative methods were lower than those identified through the subjective methods. Comparison of anatomical targets using the accelerometric data showed that to suppress rigidity in PD patients, stimulation current needed was marginally higher for Fields of Forel (FF) and Zona Incerta (ZI) compared to STN. On the other hand, the adverse effect occurrence rate was significantly lower in ZI and FF, indicating them to be better targets compared to STN. Similarly, for ET patients, other thalamic nuclei like the Intermediolateral (InL) and Ventro-Oral (VO) as well as the Pre-Lemniscal Radiations (PLR) are as efficient in suppressing tremor as the VIM but have lower occurrence of adverse effects. Volumetric analysis of spatial distribution of stimulation agreed with these results suggesting that the structures other than the VIM could also play a role in therapeutic effects of stimulation. The visualization of the adverse effect simulations clearly show the structures which could be responsible for such effects e.g. stimulation in the internal capsula induced pyramidal effects. These findings concur with the published literature. With regard to the improvement maps, the clinicians found them intuitive and easy to use to identify the optimal position for lead placement. If the maps were available during the surgery, the clinicians' choice of lead placement would have been different.
Conclusion: This doctoral work has shown that modern techniques like quantitative symptom evaluation and electric field simulations can suppress the existing drawbacks of the DBS surgery. Furthermore, these methods along with 3D visualization of data can simplify tasks for clinicians of optimizing lead placement. Better placement of the DBS lead can potentially reduce adverse effects and increase battery life of implanted pulse generator, resulting in better therapy for patients
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