Phthalates, Embryo Development, and Sperm DNA Methylation

Infertility affects 15% of all couples and presents a major public health issue. Animal and human data indicate that epigenetic dysregulation in sperm is associated with poor male reproductive health and extensive epigenetic reprogramming during spermatogenesis presents a window of vulnerability for environmentally-induced epigenetic dysregulation. Phthalates is a class of ubiquitous environmental contaminant and global health concern. Phthalate exposure in humans has been associated with diminished male fertility, adverse birth outcomes, and altered offspring development. In order to facilitate additional research on this topic, we aimed to developing a higher throughput method of sperm nucleic acid extraction. In addition, this dissertation also examined the associations of paternal phthalate exposure with sperm methylation patterns and blastocyst development. In order to maximize efficiency of the limited and difficult to acquire samples while increasing throughput for epidemiologic studies, we developed a novel method of sperm nucleic acid extraction that improved ease and efficiency. Compared to previously published methods, our new method has 1) increased yield of DNA per sperm cell, 2) reduced time required for DNA processing, and 3) eliminated the need for odorous sulfur-based reducing compounds. As part of the Sperm Environmental Epigenetics and Development Study (SEEDS), we recruited 50 couples from an in vitro fertilization (IVF) clinic. We observed that concentrations of select paternal urinary metabolites of phthalates or phthalate alternatives were associated with a marked decrease in blastocyst quality. With respect to sperm DNA methylation, we found that the male urinary anti-androgenic phthalate metabolite concentrations were associated with 131 differentially methylated regions in sperm DNA. Gene ontology analyses revealed that these differentially methylated regions were enriched in genes related to growth and development as well as cellular function and maintenance. Overall, the evidence presented by this dissertation show that paternal adult exposure to select phthalates and phthalate alternatives may influence both embryo development and sperm DNA methylation patterns. Additional work is required to replicate our findings as well as determine whether the observed aberrant sperm DNA methylation patterns associated with urinary metabolites of phthalates and phthalate alternatives are true biological mediators of the concurrent decrease in embryo quality

Model-based powertrain design and control system development for the ideal all-wheel drive electric vehicle

The transfer case based all-wheel drive electric vehicle (TCAWDEV) and dual-axle AWDEV have been investigated to balance concerns about energy consumption, drivability and stability of vehicles. However, the mentioned powertrain architectures have the torque windup issue or the wheel skidding issue. The torque windup is an inherent issue of mechanical linked all-wheel drive systems. The hydraulic motor-based or the electric motor-based ideal all-wheel drive powertrain can provide feasible solutions to the mentioned issues. An ideal AWDEV (IAWDEV) powertrain architecture and its control schemes were proposed by this research; the architecture has four independent driving motors in powertrain. The IAWDEV gives more control freedoms to implement active torque controls and traction mode controls. In essence, this research came up with the distributed powertrain concept, and developed control schemes of the distributed powertrain to replace the transfer case and differential devices. The study investigated the dual-loop motor control, the hybrid sliding mode control (HSMC) and the neural network predictive control to reduce energy consumption and achieve better drivability and stability by optimizing the torque allocation of each dependent wheel. The mentioned control schemes were respectively developed for the anti-slip, differential and yaw stability functionalities of the IAWDEV powertrain. This study also investigated the sizing method that the battery capacity was estimated by using cruise performance at 3% road grade. In addition, the model-based verification was employed to evaluate the proposed powertrain design and control schemes. The verification shows that the design and controls can fulfill drivability requirements and minimize the existing issues, including torque windup and chattering of the slipping wheel. In addition, the verification shows that the IAWDEV can harvest around two times more energy while the vehicle is running on slippery roads than the TCAWDEV and the dual-axle AWDEV; the traction control can achieve better drivability and lower energy consumption than mentioned powertrains; the mode control can reduce 3% of battery charge depleting during the highway driving test. It also provides compelling evidences that the functionalities achieved by complicated and costly mechanical devices can be carried out by control schemes of the IAWDEV; the active torque controls can solve the inherent issues of mechanical linked powertrains; the sizing method is credible to estimate the operation envelop of powertrain components, even though there is some controllable over-sizing

My wandering art in America

The wandering life of a Christian artist from China travelling to the United States and creating art that challenges the Chinese Communist Party, choosing to pursue freedom and reacting against the politics and oppression of various institutional forces

e-SAFE: Secure, Efficient and Forensics-Enabled Access to Implantable Medical Devices

To facilitate monitoring and management, modern Implantable Medical Devices (IMDs) are often equipped with wireless capabilities, which raise the risk of malicious access to IMDs. Although schemes are proposed to secure the IMD access, some issues are still open. First, pre-sharing a long-term key between a patient's IMD and a doctor's programmer is vulnerable since once the doctor's programmer is compromised, all of her patients suffer; establishing a temporary key by leveraging proximity gets rid of pre-shared keys, but as the approach lacks real authentication, it can be exploited by nearby adversaries or through man-in-the-middle attacks. Second, while prolonging the lifetime of IMDs is one of the most important design goals, few schemes explore to lower the communication and computation overhead all at once. Finally, how to safely record the commands issued by doctors for the purpose of forensics, which can be the last measure to protect the patients' rights, is commonly omitted in the existing literature. Motivated by these important yet open problems, we propose an innovative scheme e-SAFE, which significantly improves security and safety, reduces the communication overhead and enables IMD-access forensics. We present a novel lightweight compressive sensing based encryption algorithm to encrypt and compress the IMD data simultaneously, reducing the data transmission overhead by over 50% while ensuring high data confidentiality and usability. Furthermore, we provide a suite of protocols regarding device pairing, dual-factor authentication, and accountability-enabled access. The security analysis and performance evaluation show the validity and efficiency of the proposed scheme

Application of Interference Canceller in Bioelectricity Signal Disposing

AbstractBioelectricity signal is in strong interfering environment. When it is abstracted, filter is an important hinge. Adaptive interference canceller which based on LMS algorithm is excellent. It can adjust system parameter automatically. When signals are abstracted or disposed, it can play better performance. With this algorithm, this paper dispose ECG(Electrocardiograph)signal as an example in two aspect: canceling power line interference and canceling baseline shift. Both get well effect