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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.
1051

Visualisering av APD-Plan med hjälp av 3D och BIM : En studie om utveckling av APD-visualisering i byggbranschen / Visualization of construction site planning by using 3D and BIM : A study about development of site layout visualization in construction process

Alameri, Muhamed, Zaaroura, Mahmoud January 2021 (has links)
Trots den nytta som BIM har på ett projekt så finns det fortfarande företag som väljer att skapa sina APD-planer på det traditionella arbetssättet. Det traditionella arbetssättet innebär att APD-planen upprättas på den gamla metoden som vanligtvis görs med 2D. Anledningen bakom att det fortfarande finns företag som upprättar APD-planer på den traditionella arbetsmetoden är att de inte finns någon tillräcklig vilja eller kunskap att ändra arbetsmetod trots att metoden anses vara osäker och tidskrävande. Det har istället förekommit en ny arbetsmetod för att frambringa planer och ritningar som ska ersätta den traditionella arbetsmetoden. Denna arbetsmetod skapar modeller i 3D där de ingående byggkomponenterna även innehåller information. Denna arbetsmetod kallas för BIM som står för byggnadsinformationsmodellering. Modellen som upprättas med BIM och som innehåller information om de tillgängliga byggkomponenterna kallas för BIM-modell. BIM som arbetsmetod kan i sin tur användas för att skapa APD-planer med hjälp av stödjande verktyg som tex SketchUp och Revit vilket medför många fördelar.  Denna studie syftar därför till att undersöka hur APD-plan visualiseras i dagens läge samt upplysa vilka faktorer som samtliga byggföretag ska beakta vid val av verktyg för visualisering av byggarbetsplatsen. Fördelar, nackdelar samt hinder kommer att lyftas fram i denna studie med hänsyn till 3D och BIM i syfte att undersöka vilken dimension det är som lämpar sig bäst för visualisering av APD-planen samt vilken dimension APD-planen visualiseras med i dagsläget. Ytterligare ett syfte är att undersöka var i byggprocessen som APD-Planen bör integreras. Fokus kommer ligga på att påvisa fördelarna med att utöka användandet av 3D respektive BIM-relaterade APD-visualiserings verktyg. Det som tas upp i frågeställningarna är vilka de olika fördelar respektive nackdelar samt hinder som finns med att tillämpa 3D och BIM vid visualisering av APD-plan. Dessutom görs två olika visualiseringar med 3D och BIM verktyg för att visa hur APD-planen visualiseras.       Den mest användbara dimensionen vid visualisering av APD-planen är 2D där APD-planen upprättas med Bluebeam. Det finns vissa företag som har övergått till 3D vid visualisering men som kombinerar med 2D ritningar eller skisser. Att visualisera med BIM har inte varit aktuellt för de samtliga intervjuade företagen. Däremot används de färdigprojekterade BIM modellerna som en del av 3D visualiseringen i syfte att skapa en så verklighetsanpassad visualisering som möjligt. Fördelarna med att visualisera en APD-plan med 3D och BIM-verktyg är att det ger en förverkligad bild på hur byggarbetsplatsen kommer att se ut och att risker, möjligheter och problem som inte skulle kunna upptäckas med 2D-modellen blir upptäckbara. Nackdelen däremot med att visualisera en APD-plan med 3D eller BIM-verktyg är att filerna kan bli alltför tunga vilket leder i sin tur till verktyget blir svår hanterligt samt upplevs som hackigt. Det som dock hindrar många ifrån att implementera 3D och BIM-relaterade verktyg är den mänskliga faktorn som sätter stop för utvecklingen, där människans bekvämligheter och arbetsrutiner är avgörande för implementeringen av verktygen. De absolut viktigaste faktorer som ett företag bör beakta vid val av verktyg vid visualisering av APD-plan är Lönsamhet, användarupplevelse, kompatibilitet och support. / Despite the benefits that BIM has on a project, there are still companies that choose to create their APD plans in the traditional way. The reason why there are still companies that draw up APD plans on the traditional working method is that they do not have sufficient will or knowledge to change working method despite the method being considered uncertain and time consuming. Instead, there has been a new working method for producing plans and drawings that will replace the traditional working method. This working method creates models in 3D where the constituent building components also contain information. This working method is known as BIM as a wound for building information modeling. The model that is established with BIM and which contains information about the available building components is called the BIM model. BIM as a working method can in turn be used to create APD plans with the help of supporting tools such as SketchUp and Revit, which brings many benefits. This study therefore aims to investigate how APD plans are visualized in the current situation and to inform which factors all construction companies must take into account when choosing tools for visualization of the construction site. Advantages, disadvantages and obstacles will be highlighted in this study with regard to 3D and BIM in order to investigate which dimension is best suited for visualization of the APD plan and which dimension the APD plan is visualized with at present. Another purpose is to investigate where in the construction process the APD Plan should be integrated. The focus will be on demonstrating the benefits of expanding the use of 3D and BIM-related APD visualization tools, respectively. What is addressed in the issues is what are the different advantages and disadvantages as well as obstacles that exist with applying 3D and BIM when visualizing APD plans. In addition, two different visualizations are made with 3D and BIM tools to show how the APD plan is visualized. The most useful dimension in visualizing the APD plan is 2D where the APD plan is created with Bluebeam. There are some companies that have switched to 3D in visualization but which are combined with 2D drawings or sketches. Visualization with BIM has not been relevant for all the companies interviewed. On the other hand, the pre-designed BIM models are used as part of the 3D visualization in order to create as realistic a visualization as possible. The advantages of visualizing an APD plan with 3D and BIM tools are that it provides a realistic picture of what the construction site will look like and that risks, opportunities and problems that could not be detected with the 2D model become detectable. The disadvantage, however, of visualizing an APD plan with 3D or BIM tools is that the files can become too heavy, which in turn leads to the tool becoming difficult to handle and perceived as choppy. However, what prevents many from implementing 3D and BIM-related tools is the human factor that puts a stop to development, where human conveniences and work routines are crucial for the implementation of the tools. The most important factors that a company should consider when choosing tools when visualizing APD plans are Profitability, user experience, compatibility and support.
1052

Molecular characterization of XerS/difSL site-specific recombination system in Streptococcus suis

Castillo Martinez, Fabio Andres 04 1900 (has links)
L'état circulaire du chromosome bactérien pose un problème particulier lors de la réplication. Un nombre impair d'événements de recombinaison homologue donne des chromosomes dimères concaténés qui ne peuvent pas être divisés en cellules filles. Pour résoudre ce problème, les bactéries ont mis au point un mécanisme de résolution des dimères basé sur un système de recombinaison spécifique au site. Ceci est effectué par le système Xer/dif. Dans ce système, les protéines Xer effectuent une réaction de recombinaison dans le site dif au niveau du septum cellulaire immédiatement avant la division cellulaire. Dans la plupart des bactéries, cette réaction est effectuée par deux recombinases, XerC et XerD. Cependant, Streptococcus suis, un agent pathogène zoonotique important utilise un système de recombinaison différent, constitué d'une seule enzyme recombinase appelée XerS, qui catalyse la réaction de recombinaison dans un site dif non conventionnel. Pour caractériser le mode de clivage de XerS, des expériences EMSA ont été réalisées en utilisant des fragments de PCR marqués par HEX et des "suicide substrates". Nos données suggèrent que 1.) XerS est capable de lier la séquence entière de difSL; 2.) XerS lie plus efficacement le côté gauche des mutants difSL incomplets que le côté droit; 3.) XerS coupe les brins supérieur et inférieur du site difSL, avec une réaction plus efficace au bas. 4.) Modifications des nucléotides de la région la plus externe ou de la région centrale changent les préférences de clivage. 5.) XerS n'a montré aucune activité spécifique sur un autre site dif non conventionnel des Firmicutes, 6.) XerS interagit avec la sous-unité FtsK-y. L'ensemble des résultats présentés permet de mieux comprendre le fonctionnement de la recombinaison XerS dans le système de recombinase unique de Streptococcus et comment cette recombinaison est régulée par des facteurs de l'hôte. / The circular state of the bacterial chromosome presents a specific problem during replication. An odd number of homologous recombination events results in concatenated dimer chromosomes that cannot be partitioned into daughter cells. To solve this problem, bacteria have developed a mechanism of dimer resolution based on site-specific recombination system. This is performed by the Xer/dif system. In this system, the Xer proteins perform a recombination reaction in the dif site at the cell septum immediately prior to cell division. In most bacteria this reaction is performed by two recombinases, XerC and XerD. However, an important zoonotic pathogen; Streptococcus suis harbors a different recombination system, composed by a single recombinase enzyme called XerS, that catalyzes the recombination reaction in an unconventional dif site; difSL. A region characterized by two imperfect inverted repeat regions that flank a central region of 11 bp.To characterize the mode of cleavage of XerS, EMSA experiments were performed by using HEX-labelled PCR fragments and “nicked suicide substrates”. Our data suggests that; 1.) XerS is able to bind the entire difSL sequence; 2.) XerS binds more efficiently the left half side on incomplete difSL mutants than the right half side; 3.) XerS cleaves both the top and bottom strands of the difSL site, with a more efficient reaction at the bottom strand; 4.) Nucleotides at the outermost region of a T rich region seem to be determinant for binding selectivity and modifications of the extra spacing between the inverted repeat arms as well as length modifications of the central region change cleavage preference. 5.) XerS did not show any specific activity on another unconventional dif site in Firmicutes, as tested on difH. 6.) XerS interacts with FtsK-y subunit. This research aims to understand how XerS recombination works in the single recombinase system of Streptococcus and how this recombination is regulated by host factors. Exploration of these recombinases will provide a better understanding of the mechanisms of DNA exchange and genome stability in bacteria. It can also increase our knowledge of the evolution and speciation of recombinogenic bacteria.
1053

Multi-Site Leadership : Coordinating and Leading Virtual Teams

Kylefalk, Ida, Hallberg, Lova January 2020 (has links)
This study aims to recognize how virtual teams should be coordinated and led in organizations that operate at multiple sites. To fulfill the purpose of the study, a literature review on previous research on virtual teams was implemented. Further, a qualitative study including interviews with leaders at different levels at Ericsson was conducted to gain empirical data on how leadership in virtual teams works. The interviews were semi-structured with the purpose of not directing the leaders towards only bringing up the challenges that emerged in the literature review but to also bring up new perspectives. The major challenges that virtual teams face, thus challenges that the leaders must somehow address, can be divided into three areas: communication, coordination and location. Concerning communication, it is important that leaders of virtual teams set the means for communications, define ground rules and make sure that the right kind of communication is used for the right purpose. Further, it is important to communicate more often than if the team would have been co-located and actively try to build trust and cohesion within the team by being transparent and honest. To meet face to face with the team members, especially in the beginning when the team is created, is important both for understanding (virtual communication becomes easier afterward) and for the building of trust and cohesion. In the area coordination it is important for the leader to clearly define the roles of each team member and how the roles as well as the team efforts contribute to a larger picture. There is no perfect distribution that is applicable to all virtual teams, each team must find their balance concerning how many team members that should be positioned at each site. In general, to push responsibilities down in the hierarchy is a suitable role structure for virtual teams. The location area includes challenges such as different languages, cultures and collaboration across different time zones. It is important to have an operative language that all team members understand and master. When creating a new team, it is important that the leader or the person creating it, is aware of how cultural differences impact, so that the challenges can be addressed properly, and the benefits of diversity as well as the expanded labor pool, can be utilized. Working across different time zones brings benefits such as more hours of the day can be used, but it also includes challenges, such as limited real-time communication. Thus, the optimal time overlap is difficult to define, but generally, leaders prefer involving fewer time zones and large time overlaps.
1054

Engraved on Spain’s Memory : A case study of political discourses present in the media concerning three cemeteries for victims of the Civil War and the Francoist dictatorship, and their contested contribution to national reconciliation.

Soto Fernández, Francisco January 2021 (has links)
This Degree Project (DP) deals with the current discourses present on several (web)sites of memory related to three selected cemeteries for victims of the Civil War and the Francoist dictatorship and analyzes their potential contribution to national reconciliation, taking into consideration the presumed social or political interests of the actors behind the (web)sites. Collective memory must be seen as a social construction since memory stems from the shared remembrances of society and relates to key social concepts such as identity. Memory is a changeable device forged through a transformative process in which different actors are involved, from direct witnesses to memory spaces, and recently, the Internet. Memory is also discourse and as discourse is aimed at achieving power by controlling the group. Lately, the Internet has become a battlefield for competing memories, and (web)sites of memory are an opportunity to impose, in the post-truth era, a partial version of historical events. With the purpose of providing answers about whether current discourses present on (web)sites of memory can help achieve national reconciliation, this DP makes use of Discourse Analysis as a primary method, and also in-depth semi-structured interviews - in a limited number - to attain a better understanding through the uniqueness of the knowledge generated by the respondents. The Analysis has proven that, despite the time elapsed, the current discourses present on (web)sites of memory are a continuation of the old Francoist and anti-Francoist rhetoric, their contents are designed for audiences deeply committed to sociopolitical interests and, therefore, their contribution to national reconciliation is poor. The analysis has also discovered interesting initiatives aimed at exploiting the Sites and (web)sites for educational purposes. Future research may include the repetition of a similar study in the coming years, when the new Law of Democratic Memory has come into force and the political situation in Spain has evolved. It may be also advisable to use contrasting quantitative methods and enlarge the research to other cemeteries, especially, for victims of the Francoist side. / Este Degree Project (DP) aborda los discursos que actualmente pueden ser encontrados en varios sitios (web) de memoria vinculados a tres cementerios para víctimas de la Guerra Civil y la dictadura franquista, elegidos para el estudio, y analiza su potencial contribución a la reconciliación nacional, teniendo en cuenta los presuntos intereses socio-políticos de los actores detrás de estos sitios (web). La memoria colectiva debe verse como una construcción social, puesto que la memoria surge de los recuerdos compartidos de la sociedad y se relaciona con conceptos sociales clave como la identidad. La memoria es un mecanismo mutable creado por medio de un proceso transformador en el que se involucran diferentes actores, desde testigos directos hasta espacios de memoria, pero también Internet. La memoria también es discurso y como discurso tiene como objetivo alcanzar el poder controlando al grupo. Últimamente, Internet se ha convertido en un campo de batalla para recuerdos que compiten entre sí, y los sitios (web) de memoria son una oportunidad para imponer, en la era de la post-verdad, una versión parcial de los acontecimientos históricos acaecidos. Con el propósito de proporcionar respuestas sobre si los discursos actuales que están presentes en los sitios (web) de memoria pueden ayudar a lograr la reconciliación nacional, este DP hace uso del Análisis del Discurso como un método primario, y también de entrevistas en profundidad (semi-estructuradas), en un número limitado, para lograr una mejor comprensión a través de la singularidad del conocimiento generado por los participantes en la encuesta. El Análisis ha demostrado que, a pesar del tiempo transcurrido, los discursos actuales presentes en los sitios (web) de memoria son una continuación de la vieja retórica franquista y anti-franquista, sus contenidos están pensados ​​para audiencias profundamente comprometidas con intereses socio-políticos y, por ello, su contribución a la reconciliación nacional es escasa. El análisis también ha descubierto iniciativas interesantes destinadas a explotar los sitios y sitios (web) de memoria con fines educativos. La futura investigación podría centrase en la repetición de un estudio similar en años próximos, una vez haya entrado en vigor la nueva Ley de Memoria Democrática y haya evolucionado la situación política en España. También puede ser aconsejable utilizar métodos cuantitativos que permitan contrastar y ampliar la investigación a otros cementerios, especialmente, para las víctimas del bando franquista.
1055

Eléments génétiques mobiles et évolution génomique chez les Archées Thermococcales / Mobile genetic elements and genome evolution in the Archaea Thermococcales

Badel, Catherine 02 July 2019 (has links)
Les réarrangements permettent une évolution rapide du génome par l’acquisition de séquences codantes exogènes, la perte de fonctions non-essentielles ou la création de nouvelles organisations génomiques. Différents mécanismes de réarrangements impliquant des éléments génétiques mobiles (EGM) ont été identifiés chez les archées, les bactéries et les eucaryotes. En revanche, on ignore l’origine des nombreuses inversions génomiques détectées pour les espèces du genre archéen Thermococcus. Mes travaux de thèse visent à améliorer la compréhension de l’évolution génomique chez les Thermococcales à travers l’étude de deux familles d’EGM : les familles de plasmides pTN3 et pT26-2. Plus précisément, je me suis intéressée aux recombinases à tyrosine (ou intégrases) que ces plasmides encodent et qui permettent leur intégration dans le chromosome de l’hôte. J’ai montré que l’intégrase plasmidique Intᵖᵀᴺ³ est responsable d’inversions dans le chromosome de son hôte Thermococcus nautili grâce à une activité catalytique inédite de recombinaison homologue. J’ai par la suite caractérisé deux autres intégrases de Thermococcales reliés phylogénétiquement à Intᵖᵀᴺ³ dont seulement une présente une activité de recombinaison homologue. La comparaison de leurs séquences primaires et la résolution de la structure de Intᵖᵀᴺ³ vont maintenant éclairer les déterminants génétiques responsables de la spécificité de site et de l’activité de recombinaison homologue. Les trois intégrases appartiennent à une classe de recombinases spécifique des archées qui catalyse une intégration suicidaire. Lors de l’intégration, le gène de l’intégrase est fragmenté et probablement désactivé. L’EGM intégré se retrouve piégé dans le chromosome. Les avantages évolutifs d’une telle activité suicidaire restent pour l’instant mystérieux. J’ai identifié 62 intégrases hyperthermophiles suicidaires et reconstruit leur histoire évolutive. Ces intégrases sont très prévalentes et recrutées par différents EGM. De plus, j’ai montré que l’une de ces intégrases présente in vitro une activité de recombinaison site-spécifique à des températures proches de l’ébullition de l’eau, représentant un avantage dans les environnements hyperthermophiles. / Genomes rapidly evolve through rearrangements that can generate new genome organizations or lead to the acquisition of foreign coding sequences or the loss of non-essential functions. Several mechanisms of rearrangement were uncovered for Archaea, Bacteria and Eukaryotes that involve mobile genetic elements (MGE). Species from the archaeal genera Thermococcus present numerous genomic inversions but none of the previously known inversion drivers. To better understand the genomic evolution of Thermococcales, I investigated two of their MGE families: the pTN3 and pT26-2 plasmid families. Specifically, I focused on the tyrosine recombinases (or integrase) that these plasmids encode and that catalyze their site-specific integration in the host chromosome. I demonstrated that the plasmidic integrase Intᵖᵀᴺ³ is responsible for chromosomal inversions in the host Thermococcus nautili through an unprecedented homologous recombination catalytic activity. I also characterized two other related Thermococcus integrases and only one catalyzes homologous recombination. The structure resolution of Intᵖᵀᴺ³ and primary sequence comparisons will now provide clues about the genetic determinants of site specificity and of the homologous recombination activity. The three integrases all belong to an archaeal-specific class of integrases that catalyzes a suicidal integration. The integrase gene is partitioned and presumably inactivated upon integration. The integrated MGE is then trapped into the chromosome. The evolutionary benefits of this suicide activity are puzzling. I identified 62 related suicidal hyperthermophilic integrases and reconstructed their evolutionary history. They are highly prevalent and recruited by diverse MGE. I also showed that one of these integrases can catalyze in vitro site-specific recombination at near boiling water temperature, representing an advantage in hyperthermophilic environments.
1056

På spaning efter platsspecificitet i fysisk planering. : Stadsomvandlingsprojektet Köge Kysts förhållande till plats och inverkan av planeringsideal. / In search of site-specificity in urban planning. : The urban transformationproject Køge Kyst´s relation to site and the impact of planning ideals.

Jönsson, Peder, Grube Olsson, Linus January 2021 (has links)
Denna uppsats analyserar i första hand hur stort utrymme begreppet platsspecificitet får i dagens stadsplanering. I andra hand ser studien på hur plats i en allt mer generaliserad stadsplanering förhåller sig till dagens planeringsideal. Ett vanligt förekommande är att nya stadsdelar byggs utefter samma ideal, med liknande arkitektur, oavsett om det sker i en hamn, centralt i staden eller på åkermark. Planerare verkar sällan göra någon djupare platsanalys vilket kan leda till att unika plastkvaliteter förbises. I skandinavien börjar dock städer tänka mer på hur en plats kvaliteter kan upptäckas och skapas före marken exploateras permanent. I danska Köge finns stadsomvandlingsprojektet Köge Kyst, där temporära aktiviteter och mänsklig interaktion är en stor del av planeringsfasen. Genom att studera detta projektet visar den här uppsatsen ett exempel på hur en skandinavisk stad förhåller sig till plats i förhållande till rådande stadsbyggnadsideal. Med teoretiska analysverktyg studeras Köge Kyst-projektets visioner, planering och utförande där fokus ligger på platsanvändning och planeringsideal. Studien visar att Köge Kyst trots sina nya metoder för platsanvändning slutar i en stadsdel som inte sticker ut från mängden. En slutsats studien drar är att problematik uppstår många gånger i mötet mellan plats och ideal, där dessa två faktorer ofta krockar. Uppsatsen ger därför utrymme för fortsatt forskning kring platsens betydelse för hur en god och platsspecifik stadsdel kan skapas. / This study analyzes at first hand how much room the construct sitespecificity gets in today`s urban planning. In second hand this study has looked into how site in an ever more generalized urban planning relates to today´s planning ideal. A common occurrence is that new districts are built according to the same ideal, with similar architecture, no matter whether it takes part in a harbor, central in the city, or on arable land. Planners rarely seem to do a deeper site analysis, which can lead to unique sitequalities being disregarded. In Scandinavia, however, cities are beginning to think more about how a sites qualities can be discovered and created before the land is permanently built. In Danish Køge, there is an urban transformation project called Køge Kyst, where temporary activities and human interaction are a large part of the planning phase. By studying this project, this essay has provided an example of how a Scandinavian city relates to site in relation to the current planning ideal.  With theoretical analysis tools, the Køge Kyst project´s visions, planning and execution are studied, where the focus is on site-use, and planning ideals. The study shows that Køge Kyst, despite its new methods of site-use, ends up in a city transformation that does not stand out from the crowd. One conclusion the study draws is that problems often arise in the relationship between place and ideal, where these two factors often clash. This essay therefore provides scope for further research about the importance of site-understanding for the creation of new site-specific districts.
1057

The Influences and Consequences of Nest Site Choice by the Diamondback Terrapin (Malaclemys terrapin) on a Man-made Island

Leger, Daniel J. 11 June 2019 (has links)
No description available.
1058

Soil Geomorphology of the Millstone Site (36EL204) and Riverview Site (36EL203) Allegheny National Forest, Elk County, Pennsylvania

Fritz, Brian L. 09 December 2011 (has links)
No description available.
1059

"…Threaded Through": The Multitextuality of Site-Specific Music Composition

Vaughn, Mark, 1987- 08 1900 (has links)
The two fields of acousmatic music and site-specific conceptual art take strikingly different approaches to the notions of space and place. In this document, I describe how these two areas of aesthetic research diverge and relate to each other, focusing on how their unique approaches can be implemented in the practice of site-specific music composition. The first part of this document surveys the distinctive features of each of these fields, describing the particular differences between them in their approach to space and place. The contradictions between the two approaches are then briefly analyzed in reference to Georgina Born's understanding of music as fundamentally multitextual. In the second part of the document, I describe in detail how I implemented a site-specific approach when composing "…threaded through," a 16-channel audio, 6 video, site-specific installation for the UNT College of Music Main Building. In this, I describe how both the space and place of the UNT College of Music Main Building influenced my musical choices, visual content, and approach to audio and visual spatialization. The final part of the document contains a detailed score for realizing "…threaded through" in the location of the UNT College of Music Main Building.
1060

Mechanisms and consequences of DNA damage, response and apoptosis in spermatozoa.

Laubenthal, Julian January 2011 (has links)
DNA damage in spermatozoa is a crucial contributor to spontaneous abortion, severe genetic disease in the offspring and infertility. The chromatin of spermatozoa is highly compacted, transcriptionally and translationally silent, hence lacking DNA damage response (DDR). DDR foci follow within seconds after a DNA double strand break (DSB) and correlate to an abortive topoisomerase-IIb activity during spermiogenesis. When comparing the DSB frequencies at the two most fragile genomic loci (fragile sites FRA3B, FRA16D) in human and murine spermatozoa with lymphocytes, significantly increased DSB levels were detected in spermatozoa in both species. This corroborates that spermatozoa are more prone to DSBs than somatic cells. When comparing the DSB frequencies at FRA3B/FRA16D in spermatozoa of smokers with non-smokers, two-fold increases were found, probably caused by cigarette smoke components triggering abortive topoisomerase-II¿ activity. The phosphorylated DDR proteins H2AX and ATM were identified in human spermatozoa and murine spermatids using multicolour immunostaining with laser-scanning confocal microscopy (LSCM) and Western blots. Based on significantly increased DDR foci in spermatozoa of smoking men, but lacking DDR foci in response to in vitro challenge with H2O2, an abortive topoisomerase-IIb activity is the likely cause of DDR foci in spermatozoa. As DDR foci are susceptible to cigarette smoke, they can potentially be used as a novel biomarker. When comparing paternal spermatozoa, and lymphocytes as well as maternal and cord lymphocytes from 39 families for DSBs (via high-throughput LSCM pH2AX detection) and DNA fragmentation (Comet assay), significant increases were found in newborns of mothers exposed to environmental tobacco smoke and smoking fathers. When challenging lymphocytes and spermatozoa to different genotoxicants, significantly increased DNA damage in newborns compared to adults was found. This confirms an exceptional vulnerability in newborns, believed to cause increased susceptibly to disease in later life, including cancer. / European Union¿s 6th Framework project Newborns and genotoxic exposure risk (NewGeneris), British Council¿s United Kingdom Indian Education Research Initiative (UKIER)

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