313 research outputs found
Public Perceptions of the Midwest’s Pavements: Policies and Thresholds
A 5-year, pooled fund study with the Iowa, Minnesota, and Wisconsin departments of transportation assessed the public\u27s perceptions of pavement improvement strategies and developed thresholds of satisfaction using the departments\u27 physical indices, such as pavement ride and condition on rural, two-lane highways in the states. Approximately 3,600 drivers in the three states were involved in the three phases of the project, which included 18 focus groups, 400 statewide surveys in each state, and 2,300 targeted surveys across the three states. A multidisciplinary team from Marquette University and a mass media survey lab conducted the studies. A summary of focus group methods and purposes and a three-state summary of policy and improvement issues are provided. More than 450 highway segments were surveyed in Phase III, with input from 2,300 drivers through a two-step recruitment and postdrive interview. Thresholds of International Roughness Index and condition indices are summarized for the three states. The study found a high degree of trust in the three departments of transportation and public support for building longer-lasting pavements and minimizing delay. A three-step methodology is recommended for other state studies. Physical data thresholds using both public satisfaction and the agreement to improve are presented for each state\u27s physical pavement indices (ride and condition)
Public Perceptions of Wisconsin’s Pavements and Tradeoffs in Pavement Improvement
Findings are reported from Phase II of a three-phase pooled-fund project in Wisconsin, Iowa, and Minnesota to determine perceptions of drivers regarding pavement of rural two-lane highways. Among the survey topics were drivers\u27 trust in the state department of transportation (DOT), pavement improvement trade-offs, and pavement evaluation. Results of the Wisconsin portion of the survey data are the focus of this study. The survey questionnaire was based in part on Phase I focus groups conducted to gauge beliefs about pavements as well as the language describing ruts, tining, and other pavement characteristics. Phase II entailed a statewide telephone survey of at least 400 randomly selected drivers in each of the three states. Although the focus here is on Wisconsin results, survey responses across the three states were very consistent. Included in the findings discussed are perceptions of pavement and the state DOT and pavement improvement options relating to construction, travel time, and delays. Results disclose key public perceptions of priorities with regard to spending limited funds. Also discussed are statistically significant relationships providing additional insights into public perceptions and pavement improvement on rural two-lane highways
Public Perceptions of the Midwest’s Pavements - Minnesota - Executive Summary
This report summarizes Minnesota results of a five year, Pooled Fund study involving the Wisconsin, Iowa, and Minnesota DOTs designed to 1) assess the public\u27s perceptions of the departments’ pavement improvement strategies and 2) to develop customer-based thresholds of satisfaction with pavements on rural two lane highways in each state as related to the Departments’ physical indices, such as pavement ride and condition. The primary objective was to seek systematic customer input to improve the Departments’ pavement improvement policies by 1) determining how drivers perceive the departments’ pavements in terms of comfort and convenience but also in terms of other tradeoffs departments had not previously considered, 2) determining relationships between perceptions and measured pavement condition thresholds (including a general level of tolerance of winter ride conditions in two of the states), and 3) identifying important attributes and issues that may not have been considered in the past. Secondary objectives were 1) to provide a tool for systematic customer input in the future and 2) provide information which can help structure public information programs.
A University of Wisconsin-Extension survey lab conducted the surveys under the direction of a multi-disciplinary team from Marquette University. Approximately 4500 drivers in the three states participated in the three phases of the project. Researchers conducted six focus groups in each state, approximately 400 statewide telephone interviews in each state and 700-800 targeted telephone interviews in each state. Approximately 400 winter ride interviews were conducted in Wisconsin and Minnesota. A summary of the method for each survey is included.
In Phase I, focus groups were conducted with drivers to get an initial indication of what the driving public believes in regards to pavements and to frame issues for inclusion in the more representative state-wide surveys of drivers conducted in Phase II of the project. Phase II interviews gathered information about improvement policy trade-off issues and about preliminary thresholds of improvement in terms of physical pavement indices. In Phase III, a two-step recruitment and post-drive interview procedure yielded thresholds of ride and condition index summarized for each state.
Results show that, in general, the driving public wants longer lasting pavements and are willing to pay for them. They want to minimize construction delay, improve entire sections of highway at one time but they dislike detours, and prefer construction under traffic even if it stretches out construction time. Satisfaction with pavements does not correlate directly to a high degree with physical pavement indices, but was found instead to be a complex, multi-faceted phenomenon. A psychological model (after Fishbein/Ajzen) was applied to explain satisfaction to a respectable degree (R2 of .67) for the social sciences. Results also indicate a high degree of trust in the three DOTs which is enhanced when the public is asked for input on specific highway segments.
Conclusions and recommendations include a three-step methodology for other state studies. Physical data thresholds based on both public satisfaction and the agreement to improve are presented for each state\u27s physical pavement indices (ride and condition). Recommendations for changes to the quality ranges of the physical indices where appropriate are also made
Public Perceptions of the Midwest’s Pavements - Iowa - Phase III
There are several objectives to this report. The first objective is to describe the sample with regard to the physical pavement data and three measures of driver satisfaction. In this section, the proportion of respondents who are satisfied with pavements on two-lane, rural, state highways will be examined and the distribution of pavement condition and roughness indices will be presented.
The second objective will be a short description of the highway segments and any differences in satisfaction found between regions and pavement types. This was done in Phase II in each state and a letter sent showing the results in all three states. That letter sets forth the revised work plan and budget for Phase III of the project.
The third objective is to describe the relationship between physical pavement characteristics and driver satisfaction. This will include a description of both the magnitude of relationship as well as identifying critical International Road Index (IRI) and Pavement Condition Index (PCI) cutoffs where a majority of the sample were satisfied. This will be done for comparative purposes with the Phase II approach, using the total sample to compute cumulative percentages responding to each of the three series of satisfaction questions
Public Perceptions of the Midwest’s Pavements - Wisconsin - Executive Summary
This report summarizes Wisconsin results of a five year, Pooled Fund study involving the Wisconsin, Iowa, and Minnesota DOTs designed to 1) assess the public\u27s perceptions of the departments’ pavement improvement strategies and 2) to develop customer-based thresholds of satisfaction with pavements on rural two lane highways in each state as related to the Departments’ physical indices, such as pavement ride and condition. The primary objective was to seek systematic customer input to improve the Departments’ pavement improvement policies by 1) determining how drivers perceive the departments’ pavements in terms of comfort and convenience but also in terms of other tradeoffs departments had not previously considered, 2) determining relationships between perceptions and measured pavement condition thresholds (including a general level of tolerance of winter ride conditions in two of the states, including Wisconsin), and 3) identifying important attributes and issues that may not have been considered in the past. Secondary objectives were 1) to provide a tool for systematic customer input in the future and 2) provide information which can help structure public information programs.
A University of Wisconsin-Extension survey lab conducted the surveys under the direction of a multi-disciplinary team from Marquette University. Approximately 4500 drivers in the three states participated in the three phases of the project. Researchers conducted six focus groups in each state, approximately 400 statewide telephone interviews in each state and 700-800 targeted telephone interviews in each state. Approximately 400 winter ride interviews were conducted in Wisconsin and Minnesota. A summary of the method for each survey is included.
In Phase I, focus groups were conducted with drivers to get an initial indication of what the driving public believes in regards to pavements and to frame issues for inclusion in the more representative state-wide surveys of drivers conducted in Phase II of the project. Phase II interviews gathered information about improvement policy trade-off issues and about preliminary thresholds of improvement in terms of physical pavement indices. In Phase III, a two step recruitment and post-drive interview procedure yielded thresholds of ride and condition index summarized for each state.
Results show that, in general, the driving public is tolerant of a poorer ride in Winter and they understand the cause. The driving public wants longer lasting pavements and are willing to pay for them. They want to minimize construction delay, improve entire sections of highway at one time but they dislike detours, and prefer construction under traffic even if it stretches out construction time. Satisfaction with pavements does not correlate directly to a high degree with physical pavement indices, but was found instead to be a complex, multi-faceted phenomenon. A psychological model (after Fishbein/Ajzen) was applied to explain satisfaction to a respectable degree (R2 of .7) for the social sciences. Results also indicate a high degree of trust in the three DOTs which is enhanced when the public is asked for input on specific highway segments.
Conclusions and recommendations include a three-step methodology for other state studies. Physical data thresholds based on both public satisfaction and the agreement to improve are presented for each state’s physical pavement indices (ride and condition). Recommended changes to the quality ranges of the physical indices where appropriate are also made
Public Perceptions of the Midwest\u27s Pavements - Iowa - Executive Summary
This report summarizes Iowa results of a five year, Pooled Fund study involving the Wisconsin, Iowa, and Minnesota DOTs designed to 1) assess the public\u27s perceptions of the departments’ pavement improvement strategies and 2) to develop customer-based thresholds of satisfaction with pavements on rural two lane highways in each state as related to the Departments’ physical indices, such as pavement ride and condition. The primary objective was to seek systematic customer input to improve the Departments’ pavement improvement policies by 1) determining how drivers perceive the departments’ pavements in terms of comfort and convenience but also in terms of other tradeoffs departments had not previously considered, 2) determining relationships between perceptions and measured pavement condition thresholds (including a general level of tolerance of winter ride conditions in two of the states), and 3) identifying important attributes and issues that may not have been considered in the past. Secondary objectives were 1) to provide a tool for systematic customer input in the future and 2) provide information which can help structure public information programs.
A University of Wisconsin-Extension survey lab conducted the surveys under the direction of a multi-disciplinary team from Marquette University. Approximately 4500 drivers in the three states participated in the three phases of the project. Researchers conducted six focus groups in each state, approximately 400 statewide telephone interviews in each state and 700-800 targeted telephone interviews in each state. Approximately 400 winter ride interviews were conducted in Wisconsin and Minnesota. A summary of the method for each survey is included.
In Phase I, focus groups were conducted with drivers to get an initial indication of what the driving public believes in regards to pavements and to frame issues for inclusion in the more representative state-wide surveys of drivers conducted in Phase II of the project. Phase II interviews gathered information about improvement policy trade-off issues and about preliminary thresholds of improvement in terms of physical pavement indices. In Phase III, a two step recruitment and post-drive interview procedure yielded thresholds of ride and condition index summarized for each state.
Results show that, in general, the driving public wants longer lasting pavements and are willing to pay for them. They want to minimize construction delay, improve entire sections of highway at one time but they dislike detours, and prefer construction under traffic even if it stretches out construction time. Satisfaction with pavements does not correlate directly to a high degree with physical pavement indices, but was found instead to be a complex, multi-faceted phenomenon. A psychological model (after Fishbein/Ajzen) was applied to explain satisfaction to a respectable degree (R2 of .7) for the social sciences. Results also indicate a high degree of trust in the three DOTs which is enhanced when the public is asked for input on specific highway segments.
Conclusions and recommendations include a three-step methodology for other state studies. Physical data thresholds based on both public satisfaction and the agreement to improve are presented for each state\u27s physical pavement indices (ride and condition). Recommendations for changes to the quality ranges of the physical indices where appropriate are also made
Disincentives from Redistribution: Evidence on a Dividend of Democracy
We experimentally study the disincentive effect of taxing work and redistributing tax revenues when redistribution is imposed vs. democratically chosen in a vote. We find a "dividend of Democracy" in the sense that the disincentive effect is substantially smaller when redistribution is chosen in a vote than when it is imposed. Redistribution seems to be more legitimate, and hence less demotivating, when accepted in a vote.Series: WU International Taxation Research Paper Serie
Dynamische 3D-Reibungsmessung an HĂĽftendoprothesen
Im Sinne einer bauteilnahen Prüfung werden zur tribologischen Untersuchung künstlicher Hüftgelenke experimentelle Simulationen durchgeführt. Sie stellen einen wesentlichen Teil der präklinischen Evaluierung eines Implantatsystems dar. Hintergrund der Verschleißtes- tung sind Erkenntnisse aus der klinischen Forschung, nach denen die biologische Wirkung von Verschleißpartikeln auf den Organismus eine frühzeitige Lockerung des Gelenks zur Folge haben kann. Durch die Verwendung harter, verschleißarmer Materialien für die Gleit- partner und großer Kopfdurchmesser, rückt der Aspekt der Reibung verstärkt in den Fokus. Aktuelle Berichte aus der Klinik legen vielfach ein reibungsindiziertes oder -unterstütztes Versagen nahe. In der vorliegenden Arbeit wird die Erweiterung der experimentellen Simu- lation um die Messung der internen Gelenkreibung vorgestellt, validiert und verifiziert. Die Erkenntnisse aus dem vorliegenden Prüfaufbau erlauben es, Einflüsse auf (A) die Veran- kerung der Implantatkomponenten im Knochen bzw. im umgebenden Zementmantel und (B) die reibungsindizierte Korrosion an Schnittstellen von modularen Implantatsystemen zu evaluieren.
Alle Untersuchungen finden für maximal 1000 Bewegungszyklen in einer geschlossenen Kammer unter Berücksichtigung der operativen Pfannenausrichtung statt. Innerhalb die- ses Zeitraumes wurde für alle untersuchten Probenkörpern ein Einlaufen der Gleitpaarun- gen detektiert. Die Implantatkomponenten wurden im Hüftsimulator in physiologischer Orientierung getestet und als Ersatzmedium für die Gelenkflüssigkeit temperiertes Käl- berserum verwendet. Durch die Integration einer hochpräzisen Sechs-Komponenten-Kraft- /Momentensensorik und eines ebenen Luftlagers, das für einen Querkraftausgleich sorgt, wird eine Messunsicherheit des resultierenden Reibmoments von weniger als 0,5Nm er- reicht. Vergleiche mit Referenzstudien an angetriebenen Pendelaufbauten sowie zwischen Messwerten, zum einen aus einem freien Pendel mit konstanter Axiallast und zum anderen aus der physikalischen Theorie, zeigen eine gute Vergleichbarkeit zu den Ergebnissen aus dem Simulator. Erarbeitet und getestet wurden neben der standardisierten Referenz- Kinematik für die Verschleißtestung nach ISO 14242-1 zudem Aktivitätsprofile, die aus Untersuchungen mit instrumentierten Hüftimplantaten und aus der Ganganalyse gewon- nen wurde: Normales Gehen in der Ebene, Treppe auf- und Treppe absteigen. Auf die Reibung bezogen zeigt sich hierbei beim Vergleich der Kinematiken für das Normale Ge- hen, dass die Testung nach ISO 14242-1 der Belastung bei einem Patientengewicht von etwa 100-120 kg entspricht. Bei fortlaufender Simulation wurden bei allen Aktivitäten im Mittel maximale resultierende Reibmomente von weniger als 8Nm sowie Momente um die Schaftkonus-Achse im Mittel von maximal 2-3Nm gemessen. Die Einführung einer zusätzliche Pause zum Zeitpunkt der maximalen resultierenden Hüftkraft erzeugt nach In- itiierung des Ganges Losbrechmomente von über 15Nm, die u.a. abhängig sind von der Materialkombination, dem Spaltmaß zwischen Kopfaußen- und Insertinnendurchmesser, der Pausendauer und der operativen Pfannenorientierung. Eine Erhöhung der axialen Ge- lenkkompression während der Schwungphase des Gangzyklus korreliert bei Gleitpaarungen mit Polyethylen-Komponente mit der resultierende Reibung, bei rein metallischen oder ke- ramischen Kombinationen ist der Einfluss eher marginal.
Im Vergleich der Implantatmaterialien für die Gleitpaarung zeigt sich Polyethylen, das gegen einen metallischen oder keramischen Hüftkopf läuft, als am verzeihendsten gegen- über einer Fehlausrichtung der Pfannenkomponente, während besonders große keramische Systeme mit kleinem Spaltmaß eine erhöhte Reibung aufweisen. Bei den hier untersuchten Gleitpaarungen gilt, dass mit zunehmender Kopfgröße auch die Reibung im Hüftgelenk zunimmt, unabhängig von der verwendeten Materialkombination. Es ist naheliegend, dass auf Basis der vorliegenden Messergebnisse Wechselbelastungen aufgrund von Reibung, die während der Gelenkbewegung entsteht, sowohl auf die modularen Schnittstellen zwischen einzelnen Implantatkomponenten, als auch die Verankerung im Knochen über einen langen Zeitraum übertragen werden können. Der Messaufbau zur Bestimmung der dreidimensiona- len, dynamischen Reibung im Hüftgelenk ermöglicht somit die Grundlage zur Untersuchung klinisch relevanter patienten-, implantat- und operationsbezogener Einflussfaktoren über die reine Verschleißbetrachtung hinaus
Evidence for Gender-Specific Transcriptional Profiles of Nigral Dopamine Neurons in Parkinson Disease
Epidemiological data suggest that the male gender is one of the risks factors for the development of Parkinson Disease (PD). Also, differences in the clinical manifestation and the course of PD have been observed between males and females. However, little is known about the molecular aspects underlying gender-specificity in PD. To address this issue, we determined the gene expression profiles of male and female dopamine (DA) neurons in sporadic PD.We analyzed Affymetrix-based microarrays on laser microdissected DA neurons from postmortem brains of sporadic PD patients and age-matched controls across genders. Pathway enrichment demonstrated that major cellular pathways involved in PD pathogenesis showed different patterns of deregulation between males and females with more prominent downregulation of genes related to oxidative phosphorylation, apoptosis, synaptic transmission and transmission of nerve impulse in the male population. In addition, we found upregulation of gene products for metabolic processes and mitochondrial energy consumption in the age-matched male control neurons. On the single cell level, selected data validation using quantitative Real-Time (qRT)-PCR was consistent with microarray raw data and supported some of the observations from data analysis.On the molecular level, our results provide evidence that the expression profiles of aged normal and PD midbrain DA neurons are gender-specific. The observed differences in the expression profiles suggest a disease bias of the male gender, which could be in concordance with clinical observations that the male gender represents a risk factor for sporadic PD. Validation of gene expression by qRT-PCR supported the microarray results, but also pointed to several caveats involved in data interpretation
FSH prevents depletion of the resting follicle pool by promoting follicular number and morphology in fresh and cryopreserved primate ovarian tissues following xenografting
Background: Cryopreservation and transplantation of ovarian tissue is one option for re-establishing ovarian function, but optimal conditions for graft sustainment and follicular survival are still considered experimental. The present study aims to analyze the effect of FSH treatment on the resting follicle pool in fresh and cryopreserved primate ovarian tissues following xenografting. Methods: Ovarian tissues from adult marmosets were grafted freshly or following cryopreservation to ovarectomized nude mice treated with FSH 25 IU twice daily post transplantation or left untreated as controls. Grafts were retrieved 2 or 4 weeks after transplantation to evaluate the number and morphological appearance of follicles. Results: Early start of FSH treatment within 1 week following transplantation partly prevents primordial follicle loss in fresh and frozen-thawed tissues, whereas after a 3 weeks time interval this effect is present only in fresh tissues. A similar positive effect of early, but not later FSH treatment on primary follicles is seen in fresh tissues compared to only marginal effects in frozen-thawed tissues. The percentage of morphologically normal follicles is generally increased in FSH treated tissues, whereas the percentage of primary follicles over all primordial and primary follicles is increased by FSH only in freshly-grafted tissues. Conclusions: FSH treatment alleviates depletion of the resting follicle pool and promotes normal follicular morphology both in freshly and frozen-thawed grafted tissues. In previously cryopreserved tissues, applying to most of the tissues intended for clinical use in fertility preservation attempts, its positive effect on primordial follicle numbers and potential graft sustainment is dependent on an early start of treatment within one week of transplantation
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