Studies of Cardiovascular Energy Changes Occurring With Drug Administration under Normal Acid Base Balance and During Hypercapnia, Ischemia, and Metabolic Acidosis

Reflex autonomic changes occurring with the use of cardiovascular drugs may, as a side effect, increase cardiac work and oxygen demand. Improvement of coronary flow and/or a decrease in myocardial work load without increasing oxygen utilization are the desired effects of drugs used in the treatment of coronary insufficiency. The improvement of cardiac function is the purpose of drugs used in the treatment of heart failure. In either case the therapeutic effect may be accomplished through a direct myocardial effect and/or a decrease in cardiac pressure work load through extracardiac action. Through animal experimentation and patient correlation of the many parameters involved, a better understanding of the cardiodynamic effect of these drugs may be determined. This in turn may lead to drug therapy which is more apt to alleviate symptoms than those now used for specific treatment. The following studies will be included: 1) cardiovascular changes occurring during the administration of several drugs used in the treatment of cardiovascular disease will be evaluated. 2) correction of cardiovascular depression accompanying both metabolic and respiratory acidosis will be attempted with the use of several buffers and their relative efficiency determined

A Study of the Influence of Acid-Base Changes on Myocardial and Vasopressor Responses to Arterenol and Epinephrine

It is well known that when the body is subjected to various stress conditions there is almost always a reflex release of certain neurohumoral substances in an attempt to compensate for these abnormal conditions. Acid-base changes, for example, are some of the most frequent occurring under these conditions. As mentioned throughout this thesis there is a direct correlation between acidosis end extreme hypotension or shock. The objective of these experiments was to investigate and determine the influence of acidosis on the cardiovascular response to the sympatho-adrenal hormones, arterenol and epinephrine, which are released in large amounts during shock. These studies included: 1) the influence of metabolic acidosis on the responsiveness of the myocardium to epinephrine and arterenol, 2) the role of endogenous release of epinephrine and arterenol in contributing to metabolic acidosis and loss of responsiveness to these amines and 3) the production of acidosis by exogenous intravenous infusion of lactic acid, arterenol or epinephrine

The Process of Implementing Health-Promoting Schools in Zhejiang Province, China: A Dissertation

This study describes in detail the processes, interventions, challenges, and self-reported changes associated with implementing the Health-Promoting Schools (HPS) project in Zhejiang Province, China. It is a descriptive study, based on a case study model, using illustrative examples from nine schools. Grounded theory analysis revealed detailed pre-implementation, implementation, and monitoring and evaluation processes; classroom-based, school-wide and outreach activities; and modifications to the physical and psycho-social school environment. Schools faced a number of challenges related to understanding and integrating the HPS concept and a lack of professional development and support. Yet. participants reported many health-conducive changes in their attitudes, conceptual knowledge, and behaviors associated with this project. Theoretical analysis confirmed the applicability of a 3-part framework; key factors for changing policy and practice, the comprehensive HPS framework, and success factors of school health programs

Synthesis of gold micro- and nano-wires by infiltration and thermolysis

An approach for synthesizing micro- and nano-sized gold wires by infiltration and thermolysis is investigated. A porous ZrO2 ceramic preform with aligned pores obtained by unidirectional freezing and freeze-drying is employed as an infiltration template. The sintered porous ZrO2 preform is then infiltrated by a brushing gold solution. The thermolysis is conducted at 600 °C in air. Micro- and nano-sized gold wires are developed within the walls of the pores after thermolysis. The diameter of the gold wires ranges from several hundred nanometers to several microns

Getting DNA twist rigidity from single molecule experiments

We use an elastic rod model with contact to study the extension versus rotation diagrams of single supercoiled DNA molecules. We reproduce quantitatively the supercoiling response of overtwisted DNA and, using experimental data, we get an estimation of the effective supercoiling radius and of the twist rigidity of B-DNA. We find that unlike the bending rigidity, the twist rigidity of DNA seems to vary widely with the nature and concentration of the salt buffer in which it is immerged

Gauge vortex dynamics at finite mass of bosonic fields

The simple derivation of the string equation of motion adopted in the nonrelativistic case is presented, paying the special attention to the effects of finite masses of bosonic fields of an Abelian Higgs model. The role of the finite mass effects in the evaluation of various topological characteristics of the closed strings is discussed. The rate of the dissipationless helicity change is calculated. It is demonstrated how the conservation of the sum of the twisting and writhing numbers of the string is recovered despite the changing helicity.Comment: considerably revised to include errata to journal versio

A discrete geometric approach for simulating the dynamics of thin viscous threads

We present a numerical model for the dynamics of thin viscous threads based on a discrete, Lagrangian formulation of the smooth equations. The model makes use of a condensed set of coordinates, called the centerline/spin representation: the kinematical constraints linking the centerline's tangent to the orientation of the material frame is used to eliminate two out of three degrees of freedom associated with rotations. Based on a description of twist inspired from discrete differential geometry and from variational principles, we build a full-fledged discrete viscous thread model, which includes in particular a discrete representation of the internal viscous stress. Consistency of the discrete model with the classical, smooth equations is established formally in the limit of a vanishing discretization length. The discrete models lends itself naturally to numerical implementation. Our numerical method is validated against reference solutions for steady coiling. The method makes it possible to simulate the unsteady behavior of thin viscous jets in a robust and efficient way, including the combined effects of inertia, stretching, bending, twisting, large rotations and surface tension

Spatiotemporal expansion of primary progenitor zones in the developing human cerebellum

We present histological and molecular analyses of the developing human cerebellum from 30 days after conception to 9 months after birth. Differences in developmental patterns between humans and mice include spatiotemporal expansion of both ventricular and rhombic lip primary progenitor zones to include subventricular zones containing basal progenitors. The human rhombic lip persists longer through cerebellar development than in the mouse and undergoes morphological changes to form a progenitor pool in the posterior lobule, which is not seen in other organisms, not even in the nonhuman primate the macaque. Disruptions in human rhombic lip development are associated with posterior cerebellar vermis hypoplasia and Dandy-Walker malformation. The presence of these species-specific neural progenitor populations refines our insight into human cerebellar developmental disorders