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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
11

An Analysis of Thirty Border Standard Metropolitan Statistical Areas in Relation to E. W. Burgess' Concentric Zone Hypothesis

Bonner, Austin 06 1900 (has links)
This study is made to evaluate some of these forces for the thirty titled Standard Metropolitan Statistical Areas of the United States which are located on and overlap borders of two or more states. The attempt is made to determine if border SMSAs conform to the Burgess model despite state lines and other barriers imposed between SMSA parts, or whether such barriers restrict functional growth to the state side containing the central city.
12

A Factorial Ecology of Dallas County

Pol, Louis 08 1900 (has links)
The "Factorial Ecology of Dallas County" deals with the differentiation of census tracts based on combinations of census tract variables for Dallas County. The study examines this differentiation, using five factors which are analyzed in relation to concentric zone and sector theory. All of the analyses are based upon data which are available by census tract from the 1970 national census.
13

POLYMER DISPERSED LIQUID CRYSTAL DROPLETS: PROPERTIES AND APPLICATIONS

Jiang, Jinghua 28 November 2018 (has links)
No description available.
14

A Comparison of New York City's Working Class Settlement in 1940 To Burgess' Concentric Zone Theory

Maradin, Karen 04 1900 (has links)
<p> The patterns of working class settlement for New York City were established using occupation statistics found within the 1940 census. The health areas of the city's boroughs were shaded based on location quotients. Location quotients were calculated for craftsmen, operatives and labourers individually and then as a group, defining the term "total working class". The urban structure of New York City, presented in the four maps of working class settlement, failed to show the existence of five distinct concentric areas which Burgess identified in Chicago in 1925. The complicated topography, peripheral location of manufacturing industries, and lack of evenly dispersed transportation modes and bridges have contributed to the unique arrangement of settlement in New York City. </p> / Thesis / Bachelor of Arts (BA)
15

Changes in Skeletal Muscle Ultrastructure and Strength Performance following acute resistance exercise

Gibala, Martin J. 11 1900 (has links)
The purpose of this study was to examine changes in muscle ultrastructure and strength performance following a single bout of elbow flexor resistance exercise. Eight untrained males performed 8 sets of 8 repetitions at 80% concentric 1 RM. One arm performed only the concentric (CON) phase of the movement while the other performed only the eccentric (ECC) phase. Maximum isometric (MVC), low (LV} and high velocity (HV} concentric peak torque, and evoked contractile property measurements of the elbow flexors were made before and after the bout, and at 24, 48, 72 and 96 h. Needle biopsies were obtained from the biceps brachii prior to the exercise, immediately post-exercise from each arm (POSTCON, POST-ECC}, and 48 h post-exercise from each arm (48H-CON, 48H-ECC). Electron microscopy was used to quantify the extent of fiber disruption in each sample. The severity of disruption was classified as focal (FOC}, moderate (MOD}, or extreme (EXT}. All strength measurements decreased (P s; o. 05} below pre-exercise values immediately post-ex in both arms, but dramatic differences were observed between arms during the subsequent recovery period. MVC, LV, HV and peak twitch torque (PTT) recovered to pre-ex values by 24 h in the CON arm. In the ECC arm, HV did not recover for at least 72 h, and MVC, LV and PTT remained depressed at 96 h. ANOVA revealed a greater (P s; 0.05) number fibers were disrupted in the POST-CON, POST-ECC, 48H-CON and 48H-ECC samples compared to BASE. Significantly more fibers appeared disrupted in the POST-ECC (82%) and 48H-ECC (80%) samples compared to the POSTCON (33%) and 48H-CON (37%) samples, respectively. In addition, the POST-ECC (41%) and 48H-ECC (50%) samples contained a greater number of fibers with EXT disruption compared to the POST-CON (13%) and 48H-CON (17%) samples. Decreases in MVC at 48 h correlated (P ~ 0.05) with the extent of EXT disruption in the 48H-CON and 48H-ECC samples. These data indicate that both the CON and ECC phase of weightlifting produce myofibrillar disruption, with the greatest disruption occurring during the ECC phase. This study was supported by the Natural Sciences and Engineering Research Council of Canada. / Thesis / Master of Science (MSc)
16

Design comparison of ordinary concentric brace frames and special concentric brace frames for seismic lateral force resistance for low rise buildings

Grusenmeyer, Eric January 1900 (has links)
Master of Science / Department of Architectural Engineering / Kimberly Waggle Kramer / Braced frames are a common seismic lateral force resisting system used in steel structures. Ordinary concentric braced frames (OCBFs) and special concentric braced frames (SCBFs) are two major types of frames. Brace layouts vary for both OCBFs and SCBFs. This report examines the inverted-V brace layout which is one common arrangement. OCBFs are designed to remain in the elastic range during the design extreme seismic event. As a result, OCBFs have relatively few special requirements for design. SCBFs are designed to enter the inelastic range during the design extreme seismic event while remaining elastic during minor earthquakes and in resisting wind loads. To achieve this, SCBFs must meet a variety of stringent design and detailing requirements to ensure robust seismic performance characterized by high levels of ductility. The design of steel seismic force resisting systems must comply with the requirements of the American Institute of Steel Construction’s (AISC) Seismic Provisions for Structural Steel Buildings. Seismic loads are determined in accordance with the American Society of Engineers Minimum Design Loads for Buildings and Other Structures. Seismic loads are very difficult to predict as is the behavior of structures during a large seismic event. However, a properly designed and detailed steel structure can safely withstand the effects of an earthquake. This report examines a two-story office building in a region of moderately high seismic activity. The building is designed using OCBFs and SCBFs. This report presents the designs of both systems including the calculation of loads, the design of frame members, and the design and detailing of the connections. The purpose of this report is to examine the differences in design and detailing for the two braced frame systems.
17

Zusammenhang von Serum-Aldosteron und der linksventrikulären Struktur und Geometrie bei Patienten mit erhaltener linksventrikulärer Ejektionsfraktion / Serum aldosterone and its relationship to left ventricular structure and geometry in patients with preserved left ventricular ejection fraction

Knoke, Manuela 22 March 2016 (has links)
No description available.
18

Acute effect of continuous running or cycling exercise on subsequent strength performance : A Concurrent training study

Divljak, Gordan January 2016 (has links)
Aim Aerobic exercise may interfere with subsequent responses to strength training. The aim of this research was to examine the acute effects of cycling or running on subsequent leg strength performance. It was hypothesized that eccentric contractions induced by running would impair strength performance more than the cycling mode of exercise, which consist mainly of concentric muscle actions. Method In order to investigate if continuous running or cycling affected following strength performance, 6 healthy individuals (5 males, 1 female) were subjected to a randomized cross-over design. Subject characteristics were age (year) 25,5 ± 2,1, height (cm) 180,5 ± 6,4, and body weight (kg) 83 ± 3,4. The experimental sessions included three protocols: strength protocol (S) which included 3 repetitions measuring peak power followed by 3 sets to muscular failure at 80% of 1RM in the squat exercise; and continuous running (RS) and cycling (CS) conditions (40 minutes at 80% of maximal heart rate), followed by the S protocol. Peak power performance and total work volume was measured. Results Average peak power attained between the three protocols were CS = 1639± 444Watts (W), RS = 1633± 422 and S = 1565 ± 349. No significant differences were observed between the three conditions (P = 0,817). No differences across the three protocols was observed for highest peak power attained by each subject (P = 0,619). Total work volume performed (main effect P = 0,027) revealed a significant difference between CS = 2559 kg and S = 3715 kg (P=0,037), and CS and RS = 3345 kg (P=0,037) due to the lower loads lifted in CS.  Conclusions There were no differences observed between the three training protocols regarding peak power performance. When cycling exercise was performed prior to the strength session, the total volume lifted was lower than when performing the strength test alone. Thus, it is concluded that cycling exercise, but not running, interferes with subsequent strength training performance. / Syfte och frågeställningar Uthållighetsträning kan leda till försämrad styrkeprestation. Syftet med denna forskning var att undersöka de akuta effekterna från cykling eller löpning på efterföljande benstyrka. Hypotesen var att löpning, som omfattar excentriska muskelaktioner, skulle leda till en större försämring av efterföljande styrkeprestation jämfört med cyking, som främst omfattar koncentriska muskelaktioner. Metod För att undersöka om kontinuerlig cykling och löpning påverkade efterföljande benprestation, undersöktes 6 deltagare (5 män, 1 kvinna) i en randomiserad cross-over design. Försökspersonernas karakteristika var ålder (år) 25,5 ± 2,1, längd (cm) 180,5 ± 6,4, vikt (kg) 83 ± 3,4. Försökspersonerna utförde tre experimentella protokoll: styrka (S), vilket bestod av 3 repetitioner av maximal kraftutveckling efterföljt av 3 set till muskulär utmattning på 80% av 1RM i benböj; och löpning (RS) samt cykling (CS) protokoll (40-minuter på 80% av maximal hjärtfrekvens), efterföljt av S protokollet. Data för maximal kraftutveckling och total arbetsvolym samlades in.  Resultat Den genomsnittliga maximala effekten som uppnåddes mellan de tre protokollen var: CS = 1639 ± 444 Watt (W), RS = 1633 ± 422W och S = 1565 ± 349W. Inga signifikanta skillnader observerades mellan de tre förhållandena (P=0,817). Högst uppnådda effekten för varje deltagare mellan de tre förhållandena visade ingen skillnad (P=0,619). Totala arbetsvolymen (tidseffekt: P=0,027) visade signifikanta skillnader mellan CS = 2559 kg och S = 3715 kg (P=0,037), och CS och RS = 3345 kg (P=0,037) på grund av lägre vikt lyft vid CS. Slutsats Ingen skillnad observerades mellan de tre förhållandena angående maximal styrkeprestation. Den totala vikt volymen som kunde lyftas var dock lägre när cykling utfördes innan styrketestet. Slutsatsen är därför att cykling, men inte löpning, hindrar maximal träningsprestation vid ett efterföljande styrkepass.
19

Echocardiographic measurements at Takotsubo cardiomyopathy : transient left ventricular dysfunction

Waldenborg, Micael January 2014 (has links)
Takotsubo cardiomyopathy (TTC) is a disease characterized by transient left ventricular (LV) dysfunction and typical wall motion abnormalities in apical parts, without obvious signs of coronary influence. Due to its elusive natural cause and the lack of clarified pathology, further studies are needed. Thirteen patients presented with an episode of TTC, and referred to Örebro University Hospital (USÖ), were prospectively included and investigated by comparisons made at onset (acute phase) against at follow-up three months later (recovery phase). Including echocardiographic measurements, focused on biventricular systolic long-axis function and conventional diastolic function (DF) variables. Systolic improvement was shown, while most DF data were unchanged, suggesting that TTC is mainly a systolic disease affecting both ventricles. Diagnosis should include multidisciplinary engagement, as TTC associates both with emotional stress and pathological markers of physiological stress. In this thesis, such approach was offered to the aforementioned patients; to see if a common denominator could be found, thus, contributing to better handling. Emotional state was assessed, along with an array of cardiac investigations in addition to echocardiography. Acutely, imbalance in the autonomic cardiac control was shown, as well as a trend toward posttraumatic stress, but specific findings allowing conclusions on differential diagnosis could not be demonstrated. By adding another 15 TTC patients (i.e. 28 in total), through collaboration with observers from USA, a retrospective echocardiographic analysis could be done to further study DF; concluding that TTC associates with impairment of conventional DF variables which tends to parallel the systolic recovery, in contrary to the initial result but in line with other causesof LV dysfunction. Magnetic resonance imaging (MRI) is another method of choice at TTC. The USÖ patients had cardiac MRI, thus, a retrospective analysis was done to investigate the effect on LV geometry, both echocardiographic and by MRI; suggesting that TTC is consistently associated with increased LV mass, due to a local impact that seems to follow the change in LVconcentric wall motion.
20

Evaluation of force distribution within a dual special moment-resisting and special concentric-brace frame system

Wearing, Christopher January 1900 (has links)
Master of Science / Department of Architectural Engineering and Construction Science / Kimberly W. Kramer / Dual Lateral Force Resisting Systems are currently required by code to include a Moment Resisting Frame capable of resisting at least 25% of the lateral loads. This thesis evaluates the seismic performance of a specific type of dual system: a Special Moment Resisting Frame-Special Concentric Brace Frame System (SMRF-SCBF) under three different force distributions. The three distributions were 80% - 20%, 75% - 25%, and 70% - 30% with the lesser force being allotted to the Special Moment Resisting Frame (SMRF) portion of the system. In order to evaluate the system, a parametric study was performed. The parametric study consisted of three SMRF-SCBF systems designed with different seismic force distributions. The aim of this study was to determine accuracy of the three different seismic force distributions. The accuracy was measured by comparing individual system models’ data and combined system models’ data. The data used for comparison included joint deflections (both horizontal and vertical), induced moments at moment connections, brace axial loads, column shears, and column base reactions. Two-dimensional models using the structural software RISA 3D were used to assist in designing the independent Seismic Force Resisting Systems. The designs of the frames were not finely tuned (smallest member size for strength), but were designed for drift (horizontal deflection) requirements and constructability issues. Connection designs were outside the scope of the study, except for constructability considerations – the SMRF and the SCBF did not have a common column; the frames were a bay apart connected with a link beam. The results indicated that a seismic force distribution of 75% to the SCBF and 25% to the SMRF most accurately predicts that frame’s behavior. A force distribution of 80% to the SCBF and 20% to the SMRF resulted in moderately accurate results as well. A vast opportunity for further research into this area of study exists. Alterations to the design process, consideration of wind loads, or additional force distributions are all recommended changes for further research into this topic.

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