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Colorectal Cancer Screening Capacity in ArizonaBenuzillo, Jose Gerardo January 2008 (has links)
Background: Colorectal cancer is the third most commonly diagnosed cancer and the second leading cause of cancer death in Arizona. Given that by the year 2030 Arizona is expected to be the second most populated state in the U.S., it is imperative to evaluate whether this state has the colorectal screening capacity to accommodate the growing population.Methods: 338 members of the American College of Gastroenterology were invited to participate. Information for the total number of colonoscopies and sigmoidoscopies performed during an average week was ascertained by analyzing 105 surveys. We estimated the current and potential volume of screening procedures.Results: Physicians reported performing 8,717 endoscopic procedures weekly (7,990 colonoscopies and 727 sigmoidoscopies). They reported being able to increase their capacity by an additional 3,183 (36.5%) procedures a week (2,347 colonoscopies and 836 flexible sigmoidoscopies).Conclusions: Our findings suggest that Arizona has the ability to significantly expand its endoscopic capacity.
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The Effect of the Breath Builder™ on Various Lung Functions and Musical Performance Abilities of Clarinet PlayersMazon, Wendy January 2009 (has links)
The purpose of this study was to focus on the efficacy of a dynamic breath exerciser called the Breath Builder™ and its effects on clarinet players’ performance abilities and/or lung functions. The study sample consisted of 15 clarinetists, a combination of undergraduate and graduates from the clarinet studio at the University of Arizona, ages 18 - 27. The eight-week study consisted of two phases. During Phase 1, subjects in experimental group 1 used the Breath Builder™ three times a day, five times a week. The control group was not given Breath Builders™ and continued with their normal practice routine. In Phase 2, the control group was given Breath Builders™ and relabeled as experimental group 2. Experimental group 1 stopped using the Breath Builder™ and was relabeled as experimental group 3. Following this cessation, the subjects in experimental group 3 were measured to note any change in lung function or performance. Some of the pulmonary lung function measurements used for this study were, Forced Vital Capacity (FVC), Maximal Inspiratory Pressure (MIP), Maximal Inspiratory Pressure in 1 second (MIP1), and Maximal Expiratory Pressure (MEP). Musical abilities measured were tone, note duration and phrase duration. A significant interaction effect was found regarding MIP and MIP₁.
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Coded Non-Ideal OFDM Systems: Analysis and Receiver DesignsPeng, Fei January 2007 (has links)
This dissertation presents four technical contributions in the theory and practice of low-density parity-check (LDPC) codes and orthogonal frequency division multiplexing (OFDM) systems withtransmission non-linearity and with interference due to high mobility.We first explore the universality of LDPC codes for the binary erasure channel (BEC), the AWGN channel, and the flat Rayleigh fading channel. Using excess mutual information as a performance measure, we demonstrate that an LDPC code designed on a singlechannel can be universally good across the three channels. Thus, a channel for which LDPC code design is simple may be used as a surrogate for channels that are more challenging.Due to fast channel variations, OFDM systems suffer from inter-carrier interference (ICI) in frequency-selective fast fading channels. We propose a novel iterative receiver design that achieves near-optimal performance while maintaining a complexity that grows only linearly with the number of OFDM carriers. Weprove that the matched filter bound for such a channel is also the maximum-likelihood sequence detection (MLSD) bound.Because of the presence of high peaks at OFDM modulator output, amplitude clipping due to amplifier saturation causes performance degradation. We show that existing analyses underestimate the capacity of OFDM systems with clipping, and we analyze thecapacity of clipped OFDM systems with AWGN and frequency-selective Rayleigh fading. We prove that for frequency-selective Rayleigh fading channels, under certain conditions, there exists an SNR threshold, above which the capacity of a clipped system is higherthan that of an unclipped system. We provide upper and lower bounds on the channel capacity and closed-form approximations of discrete-input capacities with and without clipping.We also derive tight MLSD lower bounds and propose near-optimal receivers for OFDM systems with clipping. We show that over frequency-selective Rayleigh fading channels, under certain conditions, a clipped system with MLSD can achieve better performance than an unclipped system. We show that the MLSD boundscan be achieved or closely approached by the proposed low complexity receivers in various channel types.
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Data aggregation for capacity managementLee, Yong Woo 30 September 2004 (has links)
This thesis presents a methodology for data aggregation for capacity management. It is assumed that there are a very large number of products manufactured in a company and that every product is stored in the database with its standard unit per hour and attributes that uniquely specify each product. The methodology aggregates products into families based on the standard units-per-hour and finds a subset of attributes that unambiguously identifies each family. Data reduction and classification are achieved using well-known multivariate statistical techniques such as cluster analysis, variable selection and discriminant analysis. The experimental results suggest that the efficacy of the proposed methodology is good in terms of data reduction.
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In vitro evaluation of antioxidant properties of Rosa roxburghii plant extract / Catharina Scholtz Janse van RensburgJanse van Rensburg, Catharina Scholtz January 2003 (has links)
Rosa roxburghii, also known as "Burr Rose" or "Chestnut Rose", originated in
southwest China and was introduced to the botanic garden in Calcutta around
1824. It was named after William Roxburgh who was the superintendent. The
extract of fruit of the Rosa roxburghii plant is the base ingredient of a range of
products that is commercially sold under the Cili Bao label. The extract is
composed of a wide range of substances of nutritional value, in particular a
relatively high amount of antioxidants such as ascorbate and plant phenols. It
has been reported before that supplementation with the fruit extract
resulted in increased red blood cell superoxide dismutase, catalase and the
reduced form of glutathione. An enhancement of the antioxidant status could
contribute to the protection against several diseases where oxidative stress is a
major factor in the pathology, such as atherosclerosis, cancer and immunity
stress. Several anecdotal reports with little (published) scientific support claim
that human supplementation of the Rosa roxburghii extract to the diet has a
protective effect against several diseases, including the above mentioned.
Medicinal and herbal plants are used in large sections in developing countries for
primary care and there is now also an increase in the use of natural therapies in
developed countries. However, plant extracts can also consist of anti-nutritional
and possible toxic components, such as oxalic acid and nitrates, which could
express cytotoxic and genotoxic activities. Therefore, understanding the health
benefits but also the potential toxicity of these plants is important. The objective
of this study was to investigate the beneficial properties of Rosa roxburghii
extract from an antioxidant potential perspective and in particular to investigate
the safety of the product for human consumption. For this purpose in vitro
evaluation of the cellular toxicity, mutagenicity and genotoxicity was performed.
In addition, specific biochemical parameters relating to the antioxidant status of
the product, i.e. antioxidant capacity, oxidative stress prevention and glutathione
redox state profiles were investigated in vitro as well as in vivo.
The results indicated that Rosa Roxburghii fruit extract was not mutagenic when
tested with Salmonella typhimurium strains TA 98, TA 100 and TA 102 in the
Ames test. The results, however, pointed towards an antimutagenic effect of the
extract in these strains against metabolic activated mutagens 2-
acetylaminoflurorene (2-AAF) and aflatoxin B1, and the direct-acting mutagen,
methanesulfonate (MMS). In primary rat hepatocyte, Rosa roxbughii extract did
not elicit double or single strand DNA damage and cell viability loss using the
single cell gel electrophoresis (Comet assay), lactate dehydrogenase leakage
test or the mitochondria1 conversion test of MTT to formazan (MTT test). Again
the opposite effect was observed: pre-treatment of hepatocytes with Rosa
roxbughii extract significantly reduced the effect of oxidative stress-induced
cellular- and genotoxicity. These results point to a protective effect against
oxidative stress which is reflected in an increase of the antioxidant capacity and
glutathione redox state (GSH/GSSG) in vitro (lymphoblasts) and in vivo (humans)
reported in this study. This study underlines the previously suggested potential of
this plant extract as a natural and safe antioxidant supplement. / Thesis (M.Sc. (Biochemistry))--North-West University, Potchefstroom Campus, 2004.
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Aerobininkių aerobinis pajėgumas testuojant specifinėmis ir nespecifinėmis sąlygomis / Aerobic capacity of aerobic gymnasts while testing in specific and non-specific conditionsVaitkevičius, Deimantas 16 May 2006 (has links)
Aerobic capacity of aerobic gymnasts while testing in specific and non-specific conditions
The aim of the study: to determine an aerobic capacity of aerobic gymnasts while testing in specific and non-specific conditions.
Objectives:
· To compare submaximum heart rate and respiratory indices during treadmill and step tests.
· To compare maximum heart rate and respiratory indices during treadmill and step tests.
· To evaluate step test’s using opportunities for testing an aerobic capacity of aerobic gymnasts.
Methods:
1. Continuously increasing step test.
2. Continuously increasing treadmill test
3. Measurement of respiratory gas exchange.
4. HR monitoring and recording.
5. Measurement of blood lactate concentration.
6. Anthropometrical measurements.
The hypothesis of the study. Incremental increasing step test is able for evaluation of an aerobic capacity, heart rate and respiratory indices, especially submaximum, while testing under specific conditions, i. e. performing physical exercises on the aerobic platform dosing physical load according to the tempo of music.
Practical application. The results access the physiological knowledges about aerobic gymnasts aerobic capacity. These data can be used for individualization of the physical loads in aerobic gymnastics.
Originality of the study. First time using respiratory gas exchange telemetric system was performed an incremental increasing step test, while the physical load was dosed by music rhythm. The aerobic capacity of... [to full text]
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Vulnerability to Climate Related Events: A Case Study of the Homeless Population in Waterloo Regionde Gomez, Wendy January 2010 (has links)
Waterloo Region (population 470,000) is the eleventh largest urban region in Canada (2006 Census tract). Within this region, in 2007, 2,831 homeless people defined as commonly living or sleeping in indoor or outdoor spaces not intended for inhabitation used emergency shelters (Homelessness and Housing Group, 2008; Regional Municipality of Waterloo Region, 2007). It is expected that individuals who have inadequate or no permanent housing are particularly exposed and sensitive to environmental conditions such as extreme heat, cold events and poor air quality. Under climate change, it can be expected that the frequency of extreme events and days when air quality fails to meet healthy guidelines may increase. A wide survey of literature from environmental issues related to homelessness in first world countries has demonstrated that there is a research gap in understanding how urban citizens experiencing or facing homelessness adapt to environmental change. Therefore, this research addresses this gap by using both the vulnerability approach to local climate change assessments, and participatory action research to better understand the specificities of adaptation, the available services and future institutional strategies that could enhance the lives of this vulnerable population in relation to local environmental change. The conclusion is that people experiencing homelessness in Waterloo Region have a low vulnerability to climate related events as the social service system which they use is well developed and the climate related events are not severe. However, the vulnerability may increase in the future if service provision changes or if there is an increase in the duration, intensity and frequency of precipitation (rain) or extreme heat days.
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High-permittivity Hemispherical Lens for MIMO Applications with Closely-spaced AntennasHo, Alvin 26 November 2013 (has links)
With the rapid adoption and development of new standards, Multiple-Input Multiple-Output (MIMO) technology is becoming a necessity in current wireless systems. One problem posed by using multiple antennas at a transmitter or receiver is the undesirable effect of signal correlation between closely-spaced radiating elements. This thesis presents the concept, design, and evaluation of a hemispherical lens antenna for use in MIMO systems. A high-permittivity dielectric material allows radiating elements to be placed in close proximity with reduced spatial correlation effects. An intermediate matching layer and a hemispherical lens design facilitate the preservation of the pattern characteristics in the transition between the dielectric and free-space. The antenna was simulated against benchmark antenna arrays in free-space and showed a 35%-70% improvement in channel capacity in multipath-rich environments, showing strength as a candidate for further development in MIMO applications.
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Deployment of Indoor Small-Cells for 4G mobile BroadbandEk, Patrik January 2013 (has links)
This thesis presents an investigation of the impact of indoor small-cells. It is expected that small-cells will be able to increase the throughput and capacity for the existing networks. A deployment algorithm is presented with focus on offloading traffic from the macro layer. The performance of the deployments created with the proposed algorithm, is compared with a reference deployment. The different deployments are then simulated in a real network simulator, which performs static simulations in 3 dimension using the theory of multiple knife-edge diffraction. The small-cells increased the throughput and capacity remarkably and additional gains were obtained with the proposed algorithm. The thesis also includes strategies for small-cell deployment.
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Determinative Role of Exchange Cation and Charge Density of Smectites on their Adsorption Capacity and Affinity for Aflatoxin B1Liu, Lian 16 December 2013 (has links)
Bentonite clays have long been used as additives in animal feed, aiming to improve pellet quality and prevent caking. Certain bentonites are also capable of deactivating aflatoxin B_(1) (AfB_(1)) in feed by adsorption, therefore, detoxifying the feed. However, a 10–fold difference in adsorption capacity has been observed among selected bentonites. The major mineralogical and chemical properties of smectites in determining their adsorption capacities for AfB_(1) are still poorly understood. Improved knowledge of the key controlling factors of aflatoxin adsorption to bentonite clays is needed to guide the selection, modification, and application of the clays as aflatoxin binders.
The objective of this study was to test a hypothesis that a smectite's selectivity and adsorption capacity for aflatoxin was mainly determined by the size matching requirement on interlayer surface domains and the aflatoxin molecules. Three approaches were used to vary the size of nanometer-scaled nonpolar domains in the interlayer of smectites: 1) exchanging interlayer cations, 2) selecting natural bentonites with different cation exchange capacities (CEC), and 3) reducing charge density of a high CEC smectite.
Six bentonites were fractionated, with their major mineralogical and chemical properties determined. Clay suspensions saturated with different cations were tested for aflatoxin adsorption. Some aflatoxin-smectite complexes were prepared and analyzed with FTIR and XRD. AfB_(1) adsorption isotherms were fitted with Langmuir, modified Langmuir with adsorption dependent affinity, and exponential Langmuir models.
Divalent exchange cations with low hydration energy in general resulted in a much higher adsorption capacity and affinity for all six natural bentonite clays. Cations with smaller hydration radii tended to further enhance the adsorption process for aflatoxin on smectites. Charge density of smectite had shown significant effects on the adsorption capacity, affinity, and the isotherm shape. Aflatoxin adsorption isotherms on the six natural smectites and the CEC-reduced 5OK samples by Hofmann and Klemen effects suggested that there is an optimal CEC range between 80~110 cmol(+)/kg for the best aflatoxin binding smectites. When the smectite has a CEC within this range, the mineral has the highest affinity and adsorption capacity for AfB_(1).
The aflatoxin adsorption results after cation exchange treatment, selection of different CEC smectites, and the CEC reduction on 5OK confirmed the importance of size and polarity matching on the nanometer scale in smectites’ adsorption for AfB_(1). All clay samples tested in this study were capable of adsorbing aflatoxin into interlayers, and the charge density seemed to have no effect on bonding strength.
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