Bovine embryos produced in vitro consistently display decreased quality in terms of their potential to reach the blastocyst stage as well as post-transfer survival. Media formulations, oocyte quality, and inferior expression of needed transcripts are all causes of this reduced developmental potential commonly present in in vitro-produced (IVP) bovine embryos. Recently our lab has confirmed interleukin-6 as an embryokine whose capabilities include increasing inner cell mass (ICM) numbers and promoting bovine blastocyst development. LIF is another family member of the IL6 cytokine family and has been shown to produce several positive effects when supplemented during oocyte in vitro maturation. IL6 has predominantly been studied as being supplemented post-fertilization. However, published transcriptomic work described receptors for IL6, IL11, and LIF as present in cumulus cells at the time COCs are removed from their follicles. Consequently, we wanted to investigate if supplementing 25 ng/ml of IL6, IL11, or LIF would improve IVM bovine oocyte competency. Several experiments were completed (4replicates/experiment; 30-60 cumulus-oocyte complexes (COCs)/replicate). In Experiment 1, COCs were in vitro matured for 16 or 22 hours, then meiotic stage was assessed after denuding, fixation, and DNA staining. No cytokine treatment influenced the percentage of oocytes that achieved metaphase II at either time point. In Experiment 2, COCs were in vitro matured for 4 hours before snap freezing. and processing to examine changes in five cumulus-expressing transcripts associated with oocyte competency (CX43, CX37, AREG, TNFAIP6, HAS2). Our chosen housekeeping gene, HPRT1, served as the internal control. An increased abundance of AREG occurred following exposure to LIF but not with the other treatments. Supplementation with IL6 and IL11 but not LIF tended to increase TNFAIP6 abundance (P<0.10). No other transcript differences were detected. In Experiment 3, we examined whether supplementing these cytokines during IVM affects subsequent fertilization and blastocyst rates. No effects were detected on cleavage rates but at day 8 increases in blastocyst yield were detected for LIF and IL11, but not IL6. LIF showed a tendency to increase hatching rates. In Experiment 4, we aimed to assess how the cytokine treatments affected cryosurvivability. Blastocysts (5-10/replicate, 9 replicate studies) were frozen at a rate of -0.6 degrees C/min until reaching -32 degrees C, then were stored in liquid nitrogen for 4-8 weeks before being thawed and incubated in conventional embryo culture medium (SOF-BE1) for 3 days. No treatment effects were noted for re-expansion, hatching, and overall survivability. In summary, these results implicate IL11 and LIF as potential mediators of oocyte competency. However, the evidence presented here suggest that IL6 and IL11 may function differently than LIF when provided during COC maturation. / Master of Science / The numerous similarities in the regulation of early embryonic development between human and cow has made bovine embryos an excellent model for exploring how to optimize assisted reproductive techniques (ARTs) and other methods for improving and preserving fertility in humans. Pregnancy loss is also very similar in both cattle and humans. In beef cattle, more than 50 percent of reproductive failures occur before day 16 of gestation. In women, approximately 15 percent of all clinically recognized pregnancies result in spontaneous loss, however, several more pregnancies fail prior to ever being clinically recognized. Various ARTs are used to treat sub-fertile conditions in cattle, and these technologies are generally deemed as a viable way to improve fertility. However, IVP embryos are inferior in their ability to properly fertilize and develop to the blastocyst stage, the stage when embryos are normally transferred. Furthermore, IVP-generated embryos are inferior at maintaining pregnancies. There are two primary restraints to the IVP process: a low percentage of oocytes that become fertilized and produce transferable embryos and transferred IVP embryos have decreased chances of maintaining a viable embryo than embryos produced in vivo. Very little is known about the various hormone and molecular factors that promote oocyte and embryo development. Therefore, a primary objective for bovine oocyte and embryo research is to classify these factors and implement them into their maturation and culture media to improve overall IVP efficiency. My lab studies members of the IL6 cytokine family as potential factors that might play a role in the development of oocytes and embryos. The aim of this work is to assess the capacity of three molecules within this family, IL6, IL11, and Leukemia inhibitory factor (LIF) to improve oocyte development, fertilization rate, and blastocyst yield when supplemented during in vitro maturation (IVM). This work revealed that both IL11 and LIF improved IVP bovine blastocyst development at day 8. Unfortunately, none of the treatments had any effect on fertilization rates. LIF increased the expression of a cumulus-specific transcript known to aid in cumulus expansion. Cumulus cells are the somatic cells immediately surrounding the oocyte. Cumulus expansion is a key indicator of proper oocyte maturation. We did not observe any treatment effect on post-thaw survival of cryopreserved bovine embryos. This indicates that our treatments did not help the embryos maintain viability after undergoing a slow-freeze cryopreservation protocol followed by thawing and culture. In summary, this work showed that IL11 and LIF have potential benefits to the in vitro production of bovine embryos when supplemented at IVM. However, future work is needed to assess how these molecules are causing these improvements. Our results indicate that IL11 and LIF may function differently from IL6 when supplemented during IVM.

No description available.

This thesis presents a methodology and analysis tool to explore ship system vulnerability using a simplified modeling approach during the naval ship concept design process within the Concept and Requirements Exploration (CandRE) process used at Virginia Tech. The CandRE is based on a Multi-Objective Generic Optimization (MOGO) approach that explores a design space to produce a non-dominated set of ship design solutions comparing design effectiveness, risk, and cost. The current CandRE process evaluates ship characteristics and intact system options to determine a design Overall Measure of Effectiveness (OMOE) through the calculation of Measures of Performance (MOPs). Using the CandRE ship design process and a Preliminary Arrangement and Vulnerability (PAandV) model, an Overall Measure of Vulnerability (OMOV) is calculated for each ship design using the developed process and tools described in this thesis. The OMOV is calculated by combining the Vulnerability Measure of Performance (VMOP) scores across multiple ship mission capabilities. / Master of Science

Approved for public release; distribution in unlimited. / As a consequence of the developments in information technology and the Internet, the world is getting increasingly dependent upon distributed systems and network services. Unfortunately, the security of these services has not kept pace with the advances in information technology itself. Security practitioners accept that, a system that is connected to an unbounded network, e.g., the Internet, will be vulnerable to attacks regardless of its security features. However, the emerging discipline of survivability can help ensure that such systems deliver essential services and maintain essential properties, such as integrity, confidentiality and performance, despite the presence of intrusions. Although survivability has been accepted as a means of sufficiently addressing the security problems of current network services, unfortunately, the studies that have been done on network survivability so far are not mature enough and they lack quantifiable metrics. To address this lack of network survivability measure, a global connectivity metric is developed in this thesis. Additionally, an election protocol based on this metric is designed for the SAAM prototype to enhance the survivability of the SAAM server. / Lieutenant Junior Grade, Turkish Navy

In communication networks today, the amount of users and traffic is constantly increasing. This results in the need for upgrading the networks to handle the demand. Free space optics is a technique which is relatively cheap with high capacity compared to most systems today. On the other hand, FSO have some disadvantages with the effects on the system by, for instance, turbulence and weather. The aim of the project is to investigate the use of network optimization for designing an optimal network in terms of capacity and cost. Routing optimization is also covered in terms of singlepath and multipath routing. To mitigate the problem with turbulence affecting the system network survivability is implemented with both proactive and reactive solutions. The method used is to implement the system in Matlab, the system should also be tested so that it works as intended. The report covers related work as well as theory behind FSO and the chosen optimization algorithms. The system uses modified Bellman-Ford optimization as well as Kruskal’s minimum spanning tree. K-link-connectivity is also implemented for the network survivability and multipath algorithm. Results of the implementation shows that the network survivability improves the robustness of the system by changing paths for traffic which is affected by broken links. Routing done by multipath will increase the throughput and also reduce the delay for the traffic.

I denna uppsats behandlas hur klassningssällskapens regelverk kan bidra till ett örlogsfartygs överlevnad vid vapenverkan. Syftet är att undersöka om regelverken kan användas för att implementera stryktålighet genom sina notationer och krav på redundans, separation och skydd mot splitter. Arbetet inleds genom kunskapsuppbyggnad av teorier som behandlar örlogsfartygs överlevnad, vilka sedermera bildar arbetets teoriram. Sedan sker en analys av regelverken samt en fiktiv operativ miljö skapas för att ta fram taktiska uppgifter samt hot, vilka sedan omvandlas till verkansdelar och kritiska system. Därefter skapas modellerna som tillsammans med verkansdelarna används i simuleringen som genomförs i simuleringsverktyget Semiautomatsikt fartygs verktyg för AVAL. Simuleringarna mäter utslagssannolikheter av olika funktioner ombord vid påverkan från de framtagna verkansdelarna. Syftet är att undersöka om koncepten, vilka baseras på regelverken bidrar till mer stryktåliga plattformar. Resultatet från simuleringarna pekar på att regelverkskoncepten generellt har en lägre utslagssannolikhet vilket visar sig tydligast vid verkansdelar som genererar splitter. Arbetet kommer därmed fram till att klassningssällskapens regelverk utifrån de givna förutsättningarna kan användas för att skapa en viss nivå av stryktålighet. / This thesis deals with how the classification society’s rules may contribute to the survivability of warships when exposed to hostile fire. The aim is to examine whether the regulations can be used to reduce the vulnerability of naval ships through their notations and requirements for redundancy, separation and fragmentation protection. The first part of this thesis involves gathering information regarding relevant theory which covers the survivability of warships, which in turn forms the theoretical framework. Subsequently an analysis of the classification rules is conducted and a fictional operational environment is created in order to develop tactical tasks and threats, which are then converted into weapons effects and critical components. The models are created and together with the weapons used in the simulation program, Semi-automatic ship tool AVAL. The simulations measure the kill probabilities of different functions onboard when different weapons are used on the models. The results indicate that classification models generally have a lower kill probability, especially from weapons that generates splinters. The conclusion is that the classification society’s rules and regulations can be used to implement measures to decrease the vulnerability of naval ships.

In communication networks today, the amount of users and traffic is constantly increasing. This results in the need for upgrading the networks to handle the demand. Free space optics, FSO, is a technique which is relatively cheap with high capacity compared to most systems today. On the other hand, FSO have some disadvantages with the effects on the system by, for instance, turbulence and weather. The aim of the project is to investigate the use of network optimization for designing an optimal network in terms of capacity and cost. Routing optimization is also covered in terms of singlepath and multipath routing. To mitigate the problem with turbulence affecting the system network survivability is implemented with both proactive and reactive solutions. The method used is to implement the system in Matlab, the system should also be tested so that it works as intended. The report covers related work as well as theory behind FSO and the chosen optimization algorithms. The system uses modified Bellman-Ford optimization as well as Kruskal’s minimum spanning tree. K-link-connectivity is also implemented for the network survivability and multipath algorithm. Results of the implementation shows that the network survivability improves the robustness of the system by changing paths for traffic which is affected by broken links. Routing done by multipath will increase the throughput and also reduce the delay for the traffic.

Wireless sensor networks are widely applied to many fields such as animal habitat monitoring, air traffic control, and health monitoring. One of the current problems with wireless sensor networks is the ability to overcome communication failures due to hardware failure, distributing sensors in an uneven geographic area, or unexpected obstacles between sensors. One common solution to overcome this problem is to place a minimum number of relay nodes among sensors so that the communication among sensors is guaranteed. This is called Relay Node Placement Problem (RNP). This problem has been proved as NP-hard for a simple connected graph. Therefore, many algorithms have been developed based on Steiner graphs. Since RNP for a connected graph is NP-hard, the RNP for a survivable network has been conjectured as NP-hard and the algorithms for a survivable network have also been developed based on Steiner graphs. In this study, we show the new approximation bound for the survivable wireless sensor networks using the Steiner graphs based algorithm. We prove that the approximation bound is guaranteed in an environment where some obstacles are laid, and also propose the newly developed algorithm which places fewer relay nodes than the existing algorithms. Consequently, the main purpose of this study is to find the minimum number of relay nodes in order to meet the survivability requirements of wireless sensor networks.

Approved for public release; distribution in unlimited. / Contemporary large-scale networked systems have improved the efficiency and effectiveness of our way of life. However, such benefit is accompanied by elevated risks of intrusion and compromises. Incorporating survivability capabilities into systems is one of the ways to mitigate these risks. The Server Agent-based Active network Management (SAAM) project was initiated as part of the next generation Internet project to address the increasing multi-media Internet service demands. Its objective is to provide a consistent and dedicated quality of service to the users. SAAM monitors the network traffic conditions in a region and responds to routing requests from the routers in that region with optimal routes. Mobility has been incorporated to SAAM server to prevent a single point of failure from bringing down the entire SAAM server and its service. With mobility, it is very important to select a good SAAM server locality from the client's point of view. The choice of the server must be a node where connection to the client is most survivable. In order to do that, a general metric is defined to measure the connection survivability of each of the potential server hosts. However, due to the complexity of the network, the computation of the metric becomes very complex too. This thesis develops heuristic solutions of polynomial complexity to find the hosting server node. In doing so, it minimizes the time and computer power required. / Defence Science & Technology Agency (Singapore)

Although modeling and simulation are fertile areas for research and development within medicine, education, and human factors, there is a growing need for fully integrated organ systems as part of any digital human model (DHM). This need is particularly high in task-based survivability assessment. However, the current static geometry used in DHM is insufficient for evaluating conditions during simulated task performance. This insufficiency is due to the fact that internal viscera are inherently non-rigid objects. Therefore, undesirable, and unrealistic behaviors occur when using static models to represent internal viscera as the DHM moves through a variety of postures. The capacity for DHMs to take on a variety of postures and positions contributes to their overall usefulness in modeling and simulation. By using static models to represent internal viscera, errors in model behavior must be tolerated, or the DHM must be limited to a posture that matches the models’ configurations. With the either option being undesirable there is a need to represent internal viscera using dynamic models. A dynamic model will allow for the geometry used in representing the internal viscera to deform as the DHM. Thus this work proposes a computational platform for controlling the motion and deformation of internal viscera models within a DHM. This platform consists of two components. The first component is a new method for maintaining a relative position within a dynamic character’s mesh called skin-based parenting. The second component is a system which takes a free-from deformation technique used in artistic modeling and eliminates the manual input that is usually required. This platform produces representations of internal viscera which conform to the character’s posture in real-time at an interactive rate. Thus enabling the assessment of how particular environmental influences relate to the position and orientation of internal viscera models within a DHM in a variety of postures.