3,044 research outputs found
Assessing the Limitations of Effective Number of Samples for Finding the Uncertainty of the Mean of Correlated Data
The efficacy of recent and classical theories on the uncertainty of the mean of correlated data have been investigated. A variety of very large data sets make it possible to show that, under circumstances that are often too expensive to achieve, the integral time scale can be used to determine the effective number of independent samples, and therefore the uncertainty of the mean. To do so, the data set must be sufficiently large that it may be divided into many records, each of which is many integral time scales long. In this circumstance, all lags of the autocorrelation should be integrated to determine the integral scale. Some secondary findings include that the classical definition of the integral time scale goes identically to zero if a single record of any length is used and demonstration that measuring the integral scale requires ensemble averaging. Estimation of the integral time scale for a single record requires that the integration of the autocorrelation be truncated. This works well for signals where anti-correlation is not present. Additionally, for anti-correlated samples, the effective number of samples exceeds the number of acquired samples
TREATMENT OF PARKINSON'S DISEASE USING THE CAYCE WET CELL BATTERY
Parkinson's disease, a condition involving progressive deterioration of the nervous system, is at present incurable by conventional medicine. Here we report on a study in which we have evidence of clinical improvement from using a treatment modality recommended by Edgar Cayce, a subtle energy device known as the wet cell battery. Cayce said that the wet cell would transfer vibratory energy into the body, and specifically recommended it for neurological disorders, but there have been no previous clinical studies of this modality. T en participants with Parkinson's disease used the wet cell, a chemical battery, with gold and silver solutions, for a four-month treatment period at home. Nine of the ten people followed the protocol consistently (but none completely or perfectly). They averaged slight to moderate improvement in Parkinson's disease symptoms over four months, based on observations by researchers and subjective questionnaires. Over the long term (three years), one participant obtained almost complete remission of his Parkinson's disease symptoms. Since there was no control group the placebo effect cannot be ruled out. However, many minor symptoms showed interesting improvement in several individuals. For example, two people reported regaining their sense of smell, and one had improved color vision. Several people had more facial emotional expressiveness, and reported reduced tremors
IMPROVEMENT OF CIRCUlATION USING THE RADIAL APPLIANCE
The purpose of this study was to determine if a subtle energy device, the Cayce Radial Appliance, could improve circulation in the extremities. There were two aspects to the study: a doubleblind, placebo-controlled experiment and a small clinical investigation. In the experiment, 30 subjects were selected for cold extremities, with the criterion that either the hands or the feet had to be below 800 F during the initial measurement session. To measure improvement of circulation, we used digital thermometers to record the temperatures of the thumbs and big toes on both hands and feet. Subjects were instructed to use the appliance 16 times; laboratory measurements were taken during the 1st, 4th and 16th sessions. Skin temperature turned our to be a difficult variable to work with, due to the wide variability in temperature apparently unrelated to the experimental siruation. The strongest results were observed in the 4th session. During session baseline, differences between hand and foot temperatures of the experimental group were significantly greater than those of the control group (t [13,11] 2.49, p '" .02). The 16th session did not yield significant differences between the experimental and control groups. However, in the experimental group, there was a correlation of r (9) -.56 (p '" .07) of hand temperarure increase with the number of days it took to complete the 16 sessions. That is, those subjects who were more consistent in using the appliance may have obtained better results, though statistically the result is only suggestive due to the small sample size. In contrast, in a clinical follow-up study with five subjects and no control group, we found that all subjects had a substantial increase in hand temperature following three sessions on the appliance (Mean increase'" 8.40 F, SO = 3.3). This increase was well in excess of that seen in either the experimental or control groups in the previous study. One important difference was that in the clinical study, use of the appliance was closely supervised, whereas in the blind study most of the appliance sessions were conducted by the subjects alone in their homes
Exploitation of the Escherichia coli lac operon promoter for controlled recombinant protein production
The Escherichia coli lac operon promoter is widely used as a tool to control recombinant protein production in bacteria. Here we give a brief review of how it functions, how it is regulated, and how, based on this knowledge, a suite of lac promoter derivatives has been developed to give controlled expression that is suitable for diverse biotechnology applications
Measured temporal and spectral PMD characteristics and their implications for network-level mitigation approaches
©2003 IEEE. Personal use of this material is permitted. However, permission to reprint/republish this material for advertising or promotional purposes or for creating new collective works for resale or redistribution to servers or lists, or to reuse any copyrighted component of this work in other works must be obtained from the IEEE.Signal degradation due to polarization-mode dispersion (PMD) effects may become significant for signaling rates of 10 Gb/s, 40 Gb/s, and beyond. To assess the utility of various PMD mitigation schemes, temporal and spectral measurements of differential group delay (DGD) were made on 95 km of buried standard single-mode fiber over an 86-d period to determine the distribution and rate of change of high-DGD events. As expected, statistical analysis of variations in DGD indicate that excursions from the mean DGD by factors of 3.7 or higher have very low probability. For this link, the DGD varied slowly with time (having a drift time of about 3.4 d) and rapidly with wavelength. The DGD data agree well with results of similar experiments reported in the literature. Statistical analysis of the measured DGD data shows that high-DGD episodes will be exceedingly rare and short-lived. The impact of PMD on network operations is explored and approaches to ensure network reliability are reviewed for network operators given the task of transporting high-bit-rate channels over fiber links with known PMD characteristics
Structure and belonging: Pathways to success for underrepresented minority and women PhD students in STEM fields
The advancement of underrepresented minority and women PhD students to elite postdoctoral and faculty positions in the STEM fields continues to lag that of majority males, despite decades of efforts to mitigate bias and increase opportunities for students from diverse backgrounds. In 2015, the National Science Foundation Alliance for Graduate Education and the Professoriate (NSF AGEP) California Alliance (Berkeley, Caltech, Stanford, UCLA) conducted a wide-ranging survey of graduate students across the mathematical, physical, engineering, and computer sciences in order to identify levers to improve the success of PhD students, and, in time, improve diversity in STEM leadership positions, especially the professoriate. The survey data were interpreted via path analysis, a method that identifies significant relationships, both direct and indirect, among various factors and outcomes of interest. We investigated two important outcomes: publication rates, which largely determine a new PhD student’s competitiveness in the academic marketplace, and subjective well-being. Women and minority students who perceived that they were well-prepared for their graduate courses and accepted by their colleagues (faculty and fellow students), and who experienced well-articulated and structured PhD programs, were most likely to publish at rates comparable to their male majority peers. Women PhD students experienced significantly higher levels of distress than their male peers, both majority and minority, while both women and minority student distress levels were mitigated by clearly-articulated expectations, perceiving that they were well-prepared for graduate level courses, and feeling accepted by their colleagues. It is unclear whether higher levels of distress in women students is related directly to their experiences in their STEM PhD programs. The findings suggest that mitigating factors that negatively affect diversity should not, in principle, require the investment of large resources, but rather requires attention to the local culture and structure of individual STEM PhD programs
Understanding the nature of the optically faint radio sources and their connection to the submillimeter population
We present a sample of 43 submillimeter sources detected (at >3 sigma), drawn
from our program to follow-up optically faint radio sources with SCUBA. These
sources already have associated radio and in many cases optical
identifications, and many are also detected at 450 microns. We compare these
with 12 submillimeter sources drawn from the literature, which were discovered
in blank field mapping campaigns, but also have radio detections. We then use
this total sample (55 sources) to study and model the evolution of dusty
galaxies. A correlation is observed in the sub-mm/radio color-magnitude
diagram, which can be modeled by strong luminosity evolution. The selection
effects of the radio/optical pre-selection technique are determined from the
models, and a corrected redshift distribution is constrained using a range of
model assumptions. The temperature/redshift effects on the 450 microns detected
subset of our sample are studied in relation to the models, and prospects for
improved measurements in the shorter sub-mm wavelength windows (450 microns and
350 microns) are explored.Comment: to appear in ApJ, 19 pages, 9 figure
Subcarrier multiplexing for high-speed optical transmission
©2002 IEEE. Personal use of this material is permitted. However, permission to reprint/republish this material for advertising or promotional purposes or for creating new collective works for resale or redistribution to servers or lists, or to reuse any copyrighted component of this work in other works must be obtained from the IEEE.The performance of high-speed digital fiber-optic transmission using subcarrier multiplexing (SCM) is investigated both analytically and numerically. In order to reduce the impact of fiber chromatic dispersion and increase bandwidth efficiency, optical single-sideband (OSSB) modulation was used. Because frequency spacing between adjacent subcarriers can be much narrower than in a conventional DWDM system, nonlinear crosstalk must be considered. Although chromatic dispersion is not a limiting factor in SCM systems because the data rate at each subcarrier is low, polarization mode dispersion (PMD) has a big impact on the system performance if radiofrequency (RF) phase detection is used in the receiver. In order to optimize the system performance, tradeoffs must be made between data rate per subcarrier, levels of modulation, channel spacing between subcarriers, optical power, and modulation indexes. A 10-Gb/s SCM test bed has been set up in which 4 x 2.5 Gb/s data streams are combined into one wavelength that occupies a 20-GHz optical bandwidth. OSSB modulation is used in the experiment. The measured results agree well with the analytical prediction
10-Gb/s SCM fiber system using optical SSB modulation
©2001 IEEE. Personal use of this material is permitted. However, permission to reprint/republish this material for advertising or promotional purposes or for creating new collective works for resale or redistribution to servers or lists, or to reuse any copyrighted component of this work in other works must be obtained from the IEEE.A 10-Gb/s subcarrier multiplexing long-haul optical system is reported. 4 x 2.5 Gb/s data streams are combined into one wavelength, which occupies a 20-GHz optical bandwidth, Optical single sideband is used to increase bandwidth efficiency and reduce dispersion penalty. The receiver sensitivity is calculated using a simplified receiver model with an optical preamplifier, The measured results agree well with the analytical prediction
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