933 resultados para road tunnel


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OBIETTIVO: sintetizzare le evidenze disponibili sulla relazione tra i fattori di rischio (personali e lavorativi) e l’insorgenza della Sindrome del Tunnel Carpale (STC). METODI: è stata condotta una revisione sistematica della letteratura su database elettronici considerando gli studi caso-controllo e di coorte. Abbiamo valutato la qualità del reporting degli studi con la checklist STROBE. Le stime studio-specifiche sono state espresse come OR (IC95%) e combinate con una meta-analisi condotta con un modello a effetti casuali. La presenza di eventuali bias di pubblicazione è stata valutata osservando l’asimmetria del funnel plot e con il test di Egger. RISULTATI: Sono stati selezionati 29 studi di cui 19 inseriti nella meta-analisi: 13 studi caso-controllo e 6 di coorte. La meta-analisi ha mostrato un aumento significativo di casi di STC tra i soggetti obesi sia negli studi caso-controllo [OR 2,4 (1,9-3,1); I(2)=70,7%] che in quelli di coorte [OR 2,0 (1,6-2,7); I(2)=0%]. L'eterogeneità totale era significativa (I(2)=59,6%). Risultati simili si sono ottenuti per i diabetici e soggetti affetti da malattie della tiroide. L’esposizione al fumo non era associata alla STC sia negli studi caso-controllo [OR 0,7 (0,4-1,1); I(2)=83,2%] che di coorte [OR 0,8 (0,6-1,2); I(2)=45,8%]. A causa delle molteplici modalità di valutazione non è stato possibile calcolare una stima combinata delle esposizioni professionali con tecniche meta-analitiche. Dalla revisione, è risultato che STC è associata con: esposizione a vibrazioni, movimenti ripetitivi e posture incongrue di mano-polso. CONCLUSIONI: I risultati della revisione sistematica confermano le evidenze dell'esistenza di un'associazione tra fattori di rischio personali e STC. Nonostante la diversa qualità dei dati sull'esposizione e le differenze degli effetti dei disegni di studio, i nostri risultati indicano elementi di prova sufficienti di un legame tra fattori di rischio professionali e STC. La misurazione dell'esposizione soprattutto per i fattori di rischio professionali, è un obiettivo necessario per studi futuri.

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In the past centuries and before the invention of automobile, roads consisted mainly of unpaved paths connecting only few cities. Later, in the beginning of the twentieth century, the automobile was introduced and a new type of the transportation system was born. Therefore, it was necessary to change the condition of roads to fit with the automobiles. With the spread and the development of the automobiles, roads also have developed and increased all over the world. That caused negative effects on the environment and humans’ life quality. Thus, highways associations and communities had to take some steps to reduce these effects and care about environmental and cultural issues with the traditional commitment to safety and mobility, and that is known as context sensitive design. The aim of this thesis is to use the concepts of context sensitive design to reduce the negative environmental impacts of provincial road Galliera, which connects via Colombo in city of Bologna to provincial road 3 in Argelato city. Some solutions were proposed in this thesis to reduce traffic noise, fragmentation, fauna mortality and to improve the aesthetics of the road.

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1.Microfinance Industry – Context of Analysis. This paper is an introduction to the microfinance industry. It serves as a context of analysis, for the empirical settings and basis for building the theoretical argument for the thesis. 2.Women in Microfinance Institutions: The Road to Poverty Reduction and Gender Equality? One of the unique aspects of microfinance institutions is their focus on outreach, i.e. their ability to reach the poor. This paper explores whether the presence of women in microfinance institutions is associated with improved outreach. Building on prior research that shows that women tend to improve financial performance and social responsibility, we examine an original dataset of 226 microfinance institutions. The empirical results suggest that the presence of a female CEO, female managers and female loan officers is directly related to improved outreach, while the presence of women board members is not. 3. Women in Microfinance Institutions: Is There a Trade-Off Between Outreach and Sustainability? Abstract This paper’s contribution to the understanding of microfinance is two-fold. First, while it has been shown that female CEOs in MFIs increase financial performance, it will be argued that female managers, female loan officers and female board members will do the same. Secondly, having previously shown that having a female presence in management in MFIs improves social performance the outreach, it will be argued that having females in the MFIs’ management will not lead to a trade-off between outreach and sustainability. These findings are based on an original data set of 226 MFIs. Statistical analysis demonstrates that a weak relationship between female managers and female loan officers vis-à-vis financial performance, but female board members do not. The trade-off between outreach and sustainability can be avoided with the appointment of females to the MFIs’ management positions, but the same cannot be concluded for female board members.

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Joseph Nicolas Cugnot built the first primitive car in 1769 and approximately one hundred year later the first automotive race took place. Thanks to this, for the first time the aerodynamics principles began to be applied to cars. The aerodynamic study of a car is important to improve the performance on the road, or on the track. It purposely enhances the stability in the turns and increases the maximum velocity. However, it is also useful, decrease the fuel consumption, in order to reduce the pollution. Given that cars are a very complex body, the aerodynamic study cannot be conducted following an analytical method, but it is possible, in general, to choose between two different approaches: the numerical or the experimental one. The results of numerical studies depend on the computers’ potential and on the method use to implement the mathematical model. Today, the best way to perform an aerodynamic study is still experimental, which means that in the first phase of the design process the study is performed in a wind tunnel and in later phases directly on track. The automotive wind tunnels are singular mainly due to the test chamber, which typically contains a ground simulation system. The test chamber can have different types of walls: open walls, closed walls, adaptive walls or slotted walls. The best solution is to use the slotted walls because they minimize the interference between the walls and the streamlines, the interaction between the flow and the environment, and also to contain the overall costs. Furthermore, is necessary minimize the boundary layer at the walls, without accelerating the flow, in order to provide the maximum section of homogeneous flow. This thesis aims at redefining the divergent angle of the Dallara Automobili S.P.A. wind tunnel’s walls, in order to improve the overall homogeneity. To perform this study it was necessary to acquire the pressure data of the boundary layer, than it was created the profile of the boundary layer velocity and, to minimize the experimental errors, it was calculated the displacement thickness. The results obtained shows, even if the instrument used to the experiment was not the best one, that the boundary layer thickness could be minor in case of a low diffusion angle. So it is convenient to perform another experiment with a most sensitive instrument to verified what is the better wall configuration.

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In areas of seasonal frost, frost susceptibility composed by frost heaving during the winter and thaw softening during the spring is one of the most dangerous phenomenon for transportation, road and railway infrastructure. Therefore, the need for frost protection layer becomes imperative. The purpose of frost protection layer is to prevent frost from penetrating down through the pavement and into the sub-soils. Frost susceptible soils under the road can be cause damages on the roads or other structures due to frost heave or reduced capacity characteristics thaw period. "Frost heave" is the term given to the upwards displacement of the ground surface caused by the formation of ice within soils or aggregates (Rempel et al., 2004). Nowadays in Scandinavia the most common material used in frost protection layer in the pavement structure of roads and in the ballast of the railway tracks are coarse-grain crushed rocks aggregates. Based on the capillary rise, the mechanics of frost heave phenomenon is based on the interaction between aggregates and water, as suggested by Konrad and Lemieux in 2005 that said that the fraction of material below the 0.063 mm sieve for coarse-grained soils must be controlled so as to reduce the sensitivity to frost heave. The study conducted in this thesis project is divided in two parts: - the analysis of the coarse grained aggregates used in frost protection layer in Norway; - the analysis of the frost heave phenomenon in the laboratory under known boundary conditions, through the use of the most widely used method, the frost heave test, in” closed system” (without access of water).

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L'obiettivo del presente elaborato è di fornire una proposta di traduzione dall'inglese all'italiano del poema "The White Road" di Neil Gaiman, pubblicato in Ruby Slippers, Golden Tears (1995) e in Smoke and Mirrors (1998). L'elaborato è articolato in: una breve presentazione dell’autore, con accento sui temi ricorrenti presenti nelle sue opere; una descrizione del testo scelto, sia in termini di struttura che di contenuti e riferimenti culturali; la proposta di traduzione con testo originale a fronte; un’analisi dei problemi traduttivi riscontrati con le relative soluzioni adottate.

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Il presente lavoro tratta la stabilità del fronte di scavo, rinforzato con barre di consolidamento ed interessato da drenaggi in avanzamento, di gallerie sotto falda in rocce tenere o terreni. Tale studio è stato sviluppato dal progetto di Tesi attraverso l’analisi all’equilibrio limite che approssima il fronte di scavo con un rettangolo e considera un meccanismo di rottura composto da un cuneo, a tergo del fronte, caricato da un prisma. Il metodo descritto consente di tenere conto dell’effetto stabilizzante delle barre, mediante una distribuzione della pressione di supporto non uniforme. Nel caso di gallerie sotto falda, lo stesso metodo permette inoltre di considerare l’effetto destabilizzante dei gradienti idraulici. Sono state ricavate soluzioni analitiche per la valutazione della stabilità, ed implementate successivamente nel software di analisi numerica MATLAB. Dalle analisi condotte è emerso che il numero minimo di barre per garantire la stabilità del fronte di scavo è in molti casi elevato e risulta impossibile da porre in opera in terreni scarsamente coesivi o in gallerie sotto elevati battenti d’acqua. Per risolvere questa situazione si può prevedere l’inserimento di drenaggi in avanzamento, con lo scopo di diminuire i gradienti idraulici nei pressi del fronte della galleria. Il modello che descrive il nuovo andamento dei carichi idraulici, considerando la presenza di dreni, è stato realizzato con il software commerciale agli elementi finiti COMSOL. Una volta determinati gli andamenti dei carichi idraulici, sono stati condotti studi parametrici sull’effetto dei dreni combinato con gli elementi di rinforzo. Dopo tali analisi sono stati ricavati nomogrammi adimensionali che tengano conto della presenza contemporanea delle barre e dei dreni. Tali diagrammi costituiscono uno strumento utile e valido per la progettazione del rinforzo del fronte di scavo. Infine sono stati realizzati confronti fra casi di studio reali e risultati ottenuti dal modello.

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L’obiettivo del progetto è stato quello di realizzare ed analizzare aggregati artificiali creati attraverso geopolimerizzazione e macro-incapsulazione di paraffina in aggregati leggeri espansi, discutendo i loro possibili impieghi nelle pavimentazioni stradali. Dopo un'accurata calibrazione delle miscele geopolimeriche, sono stati realizzati degli aggregati artificiali, in seguito caratterizzati in accordo con la norma UNI EN 10343, con l'intento di sostituire materiali stradali vergini. Contemporaneamente, sono stati prodotti aggregati leggeri impregnati di paraffina (PCM), in grado di cambiare fase una volta raggiunti all'incirca i 3 °C, e successivamente rivestiti da due strati di resina poliestere e polvere di granito, denominati PLA: sfruttandone le proprietà termiche, si è valutato il loro possibile utilizzo come soluzione anti-icing. L’ultima fase della ricerca è stata incentrata nella realizzazione di aggregati geopolimerici espansi e molto porosi che potessero contenere una elevata quantità di PCM, sostituendo l'argilla espansa utilizzata nella produzione degli PLA.

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Road traffic accidents (RTA) are an important cause of premature death. We examined socio-demographic and geographical determinants of RTA mortality in Switzerland by linking 2000 census data to RTA mortality records 2000-2005 (ICD-10 codes V00-V99). Data from 5.5 million residents aged 18-94 years, 1744 study areas, and 1620 RTA deaths were analyzed, including 978 deaths (60.4%) in motor vehicle occupants, 254 (15.7%) in motorcyclists, 107 (6.6%) in cyclists, and 259 (16.0%) in pedestrians. Weibull survival models and Bayesian methods were used to calculate hazard ratios (HR), and standardized mortality ratios (SMR) across study areas. Adjusted HR comparing women with men ranged from 0.04 (95% CI 0.02-0.07) in motorcyclists to 0.43 (95% CI 0.32-0.56) in pedestrians. There was a u-shaped relationship with age in motor vehicle occupants and motorcyclists. In cyclists and pedestrians, mortality increased after age 55 years. Mortality was higher in individuals with primary education (HR 1.53; 95% CI 1.29-1.81), and higher in single (HR 1.24; 95% CI 1.05-1.46), widowed (HR 1.31; 95% CI 1.05-1.65) and divorced individuals (HR 1.62; 95% CI 1.33-1.97), compared to persons with tertiary education or married persons. The association with education was particularly strong for pedestrians (HR 1.87; 95% CI 1.20-2.91). RTA mortality increased with decreasing population density of study areas for motor vehicle occupants (test for trend p<0.0001) and motorcyclists (p=0.0021) but not for cyclists (p=0.39) or pedestrians (p=0.29). SMR standardized for socio-demographic and geographical variables ranged from 82 to 190. Prevention efforts should aim to reduce inequities across socio-demographic and educational groups, and across geographical areas, with interventions targeted at high-risk groups and areas, and different traffic users, including pedestrians.

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Purpose To compare changes in the largest cross-sectional area (CSA) of the median nerve in wrists undergoing surgical decompression with changes in wrists undergoing non-surgical treatment of carpal tunnel syndrome (CTS). Methods This study was a prospective cohort study in 55 consecutive patients with 78 wrists with established CTS, including 60 wrists treated with surgical decompression and 18 wrists with non-surgical treatment. A sonographic examination was scheduled before and 4 months after initiation of treatment. We compared changes in CSA of the median nerve between wrists with surgical treatment and wrists with non-surgical treatment using linear regression models. Results Decreases in CSA of the median nerve were more pronounced in wrists with CTS release than in wrists undergoing nonsurgical treatment (difference in means, 1.0 mm2; 95% confidence interval, 0.3–1.8 mm2). Results were robust to the adjustment for age, gender, and neurological severity at baseline. Among wrists with CTS release, those with postoperative CSA of 10 mm2 or less tended to have better clinical outcomes than those with postoperative CSA of greater than 10 mm2 (p=.055). Postoperative sonographic workup in the 3 patients with unfavorable outcome or recurrence identified likely causes for treatment failure in 2 patients. Conclusions In this observational study, surgical decompression was associated with a greater decrease in median nerve CSA than was nonsurgical treatment. Smaller postoperative CSAs may be associated with better clinical outcomes. Additional randomized trials are necessary to determine the optimal treatment strategy in different subgroups of patients with CTS. Type of study/level of evidence Therapeutic III.

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High-resolution ultrasound is becoming increasingly important in the diagnosis of carpal tunnel syndrome (CTS). Most studies define cut-off values of the cross-sectional area (CSA) of the median nerve in different locations. The individual range of nerve swelling, the size of the nerve, and its CSA are not addressed. The aim of the study is to define the intra- and interobserver reliability of diagnostic ultrasound using two different cross-sectional areas of the median nerve at the carpal tunnel in predefined locations.

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Sulcus ulnaris syndrome is the second most common neurocompression syndrome in the upper limb after carpal tunnel syndrome. Its severity can be appreciated by the Dellon Classification. We present our experience and results after endoscopic decompression.