2,310 research outputs found
Andrew Johnson\u27s Impact on Reconstruction
I began this historiography with a list of five possible topics to choose from related to the Reconstruction Era. From there, I chose the topic of Andrew Johnson and Reconstruction because I had never known much about the seventeenth President of the United States. I began to conduct research, navigating online databases and scanning the Roesch library for possible sources. I compiled a list of fifteen sources from which I chose a final eight. Summarizing each source and taking note of recurring themes, I composed an annotated bibliography. This served as the first draft of my historiography. I transformed this annotated bibliography into a historiographical essay by organizing the sources according to common themes and forming a thesis. The essay was completed with the addition of comparison between sources and the formulation of supporting argument for the thesis
Uniaxial and biaxial soft deformations of nematic elastomers
We give a geometric interpretation of the soft elastic deformation modes of
nematic elastomers, with explicit examples, for both uniaxial and biaxial
nematic order. We show the importance of body rotations in this non-classical
elasticity and how the invariance under rotations of the reference and target
states gives soft elasticity (the Golubovic and Lubensky theorem). The role of
rotations makes the Polar Decomposition Theorem vital for decomposing general
deformations into body rotations and symmetric strains. The role of the square
roots of tensors is discussed in this context and that of finding explicit
forms for soft deformations (the approach of Olmsted).Comment: 10 pages, 10 figures, RevTex, AmsTe
Photonic crystal resonator integrated in a microfluidic system
We report on a novel optofluidic system consisting of a silica-based 1D
photonic crystal, integrated planar waveguides and electrically insulated
fluidic channels. An array of pillars in a microfluidic channel designed for
electrochromatography is used as a resonator for on-column label-free
refractive index detection. The resonator was fabricated in a silicon
oxynitride platform, to support electroosmotic flow, and operated at 1.55
microns. Different aqueous solutions of ethanol with refractive indices ranging
from n = 1.3330 to 1.3616 were pumped into the column/resonator and the
transmission spectra were recorded. Linear shifts of the resonant wavelengths
yielded a maximum sensitivity of 480 nm/RIU and a minimum difference of 0.007
RIU was measured
Electrocardiographic alterations during intravascular application of three different test doses of bupivacaine and epinephrine: experimental study in neonatal pigs
Background Origin of electrocardiographic (ECG) alterations during intravascular injection of local anaesthetic solutions is controversial. The aim of this study was to elucidate whether epinephrine, bupivacaine or their combination is responsible for ECG alteration. Methods Forty-five piglets were randomized into three groups. After induction of general anaesthesia using sevoflurane and peripheral venous cannulation, the trachea was intubated, the lungs were artificially ventilated, and anaesthesia was maintained by sevoflurane. Under steady state 0.2 ml kg−1 and after 10 min 0.4 ml kg−1 of one of the following three test solutions was administered i.v.: bupivacaine 0.125% (Group 1), bupivacaine 0.125%+epinephrine 1:200 000 (Group 2), and plain epinephrine 1:200 000 (Group 3). The ECG was analysed for alterations in heart rate and T-elevation. Results After injection of 0.2 or 0.4 ml kg−1 test solution, an increase in heart rate of at least 10% was found in none of Group 1 and in all of Groups 2 and 3. After application of 0.2 ml kg−1 test solution, T-elevation was found in 7% of Group 1 and in 93% of Groups 2 and 3. The injection of 0.4 ml kg−1 revealed a T-elevation in 27%, 100%, and 100%, respectively, in Groups 1, 2, and 3. Conclusions This animal model demonstrated that increases in heart rate and T-elevation in the ECG during i.v. application of a common test dose (0.2 ml kg−1) of bupivacaine are caused by epinephrine addition. Whether higher doses of bupivacaine alone can cause similar ECG changes or not requires further studie
Electrocardiographic changes during continuous intravenous application of bupivacaine in neonatal pigs
Background It is controversial as to whether T-wave elevation is caused by local anaesthetics, epinephrine, or their combination. It has been shown that T-elevation after intravascular injection of a small bupivacaine test dose is caused by epinephrine and not by bupivacaine. The aim of this study was to investigate ECG changes with higher doses of i.v. bupivacaine. Methods Thirty neonatal pigs were anaesthetized with sevoflurane and their tracheas intubated and artificially ventilated. Under steady-state conditions, bupivacaine was continuously infused (flow rate 3.2 ml kg−1 min−1) by a syringe infusion pump through a central venous catheter. Group 1 received bupivacaine 0.125%, Group 2 bupivacaine 0.5%. The ECG was continuously printed and subsequently analysed for alterations in heart rate, ventricular de- and repolarization, and arrhythmias at 1.25, 2.5, and 5 mg kg−1 bupivacaine infused. Results Sinus rhythm persisted in all pigs. Heart rate decreased progressively in both groups, but this was significantly more pronounced in Group 1. T-wave elevation occurred in 40% and 0% (Groups 1 and 2) at 1.25 mg kg−1, in 80% and 0% at 2.5 mg kg−1, and in 93% and 80% at 5 mg kg−1 bupivacaine infused. There were significant differences between the two groups at 1.25 and 2.5 mg kg−1 infused. Conclusions Higher doses of i.v. infused bupivacaine can cause T-elevation. With slower injection technique, T-elevation can already be detected at lower bupivacaine doses administere
Characterizing the pulsations of the ZZ Ceti star KUV 02464+3239
We present the results on period search and modeling of the cool DAV star KUV
02464+3239. Our observations resolved the multiperiodic pulsational behaviour
of the star. In agreement with its position near the red edge of the DAV
instability strip, it shows large amplitude, long period pulsation modes, and
has a strongly non-sinusoidal light curve. We determined 6 frequencies as
normal modes and revealed remarkable short-term amplitude variations. A
rigorous test was performed for the possible source of amplitude variation:
beating of modes, effect of noise, unresolved frequencies or rotational
triplets. Among the best-fit models resulting from a grid search, we selected 3
that gave l=1 solutions for the largest amplitude modes. These models had
masses of 0.645, 0.650 and 0.680 M_Sun. The 3 `favoured' models have M_H
between 2.5x10^-5 - 6.3x10^-6 M_* and give 14.2 - 14.8 mas seismological
parallax. The 0.645 M_Sun (11400 K) model also matches the spectroscopic log g
and T_eff within 1 sigma. We investigated the possibility of mode trapping and
concluded that while it can explain high amplitude modes, it is not required.Comment: 11 pages, 8 figures, accepted for publication in MNRA
Mechanical response of plectonemic DNA: an analytical solution
We consider an elastic rod model for twisted DNA in the plectonemic regime.
The molecule is treated as an impenetrable tube with an effective, adjustable
radius. The model is solved analytically and we derive formulas for the contact
pressure, twisting moment and geometrical parameters of the supercoiled region.
We apply our model to magnetic tweezer experiments of a DNA molecule subjected
to a tensile force and a torque, and extract mechanical and geometrical
quantities from the linear part of the experimental response curve. These
reconstructed values are derived in a self-contained manner, and are found to
be consistent with those available in the literature.Comment: 14 pages, 4 figure
- …