A Review of Resonant Converter Control Techniques and The Performances

paper first discusses each control technique and then gives experimental results and/or performance to highlights their merits. The resonant converter used as a case study is not specified to just single topology instead it used few topologies such as series-parallel resonant converter (SPRC), LCC resonant converter and parallel resonant converter (PRC). On the other hand, the control techniques presented in this paper are self-sustained phase shift modulation (SSPSM) control, self-oscillating power factor control, magnetic control and the H-∞ robust control technique

Sox10 regulates enteric neural crest cell migration in the developing gut

Concurrent Sessions 1: 1.3 - Organs to organisms: Models of Human Diseases: abstract no. 1417th ISDB 2013 cum 72nd Annual Meeting of the Society for Developmental Biology, VII Latin American Society of Developmental Biology Meeting and XI Congreso de la Sociedad Mexicana de Biologia del Desarrollo. The Conference's web site is located at http://www.inb.unam.mx/isdb/Sox10 is a HMG-domain containing transcription factor which plays important roles in neural crest cell survival and differentiation. Mutations of Sox10 have been identified in patients with Waardenburg-Hirschsprung syndrome, who suffer from deafness, pigmentation defects and intestinal aganglionosis. Enteric neural crest cells (ENCCs) with Sox10 mutation undergo premature differentiation and fail to colonize the distal hindgut. It is unclear, however, whether Sox10 plays a role in the migration of ENCCs. To visualize the migration behaviour of mutant ENCCs, we generated a Sox10NGFP mouse model where EGFP is fused to the N-terminal domain of Sox10. Using time-lapse imaging, we found that ENCCs in Sox10NGFP/+ mutants displays lower migration speed and altered trajectories compared to normal controls. This behaviour was cell-autonomous, as shown by organotypic grafting of Sox10NGFP/+ gut segments onto control guts and vice versa. ENCCs encounter different extracellular matrix (ECM) molecules along the developing gut. We performed gut explant culture on various ECM and found that Sox10NGFP/+ ENCCs tend to form aggregates, particularly on fibronectin. Time-lapse imaging of single cells in gut explant culture indicated that the tightly-packed Sox10 mutant cells failed to exhibit contact inhibition of locomotion. We determined the expression of adhesion molecule families by qPCR analysis, and found integrin expression unaffected while L1-cam and selected cadherins were altered, suggesting that Sox10 mutation affects cell adhesion properties of ENCCs. Our findings identify a de novo role of Sox10 in regulating the migration behaviour of ENCCs, which has important implications for the treatment of Hirschsprung disease.postprin

Analysis of molecular forces transmitted by Talin during muscle development in vivo

The muscle-tendon system built during the development of an animal is essential to allow the body to move, breath or keep the heart beating for a lifetime. The muscle is the most important force producing tissue in an animal and, at the same time, it is also dependent on forces built up in the muscle-tendon tissue, especially during its development. Using the Drosophila musculature as a model system, it had been shown that tension is built up in the muscle-tendon tissue during development and that this tension is required for myofibrillogenesis, the process of building myofibrils, which are long chains of the contractile units of muscles called sarcomeres. The main focus of this thesis was to analyze how tension in tissues is transmitted across proteins at the molecular level to understand how proteins sense and respond to mechanical forces in vivo. As a model system, the developing Drosophila flight muscles were used that form in the pupal stage of the Drosophila life cycle. During development, these muscles attach to tendon cells and the connections between these two cells, called muscle attachment sites, need to bear the forces built up in the tissue. Muscle attachments are cell-extracellular matrix (ECM)-cell contacts that require receptor molecules in the cell membrane called integrins to connect the ECM between the cells with the contractile actin cytoskeleton inside the cells. Since integrins cannot directly connect to actin themselves, they require an adaptor protein called Talin that can bind to both integrin and actin filaments. Thus, Talin is in the ideal position to transmit and sense forces at muscle attachments. Previous studies on Talin force transduction demonstrated that Talin indeed bears forces in the piconewton (pN) range using Förster resonance energy transfer (FRET)-based molecular tension sensors. However, these studies were based on analyzing Talin in focal adhesions in cells cultured in vitro in an artificial environment. Therefore, we aimed to analyze Talin force transmission for the first time in vivo in the natural mechanical environment in the intact organism. In a first step, different FRET-based tension sensor modules and various control constructs were inserted in Drosophila into the endogenous talin (rhea) gene, taking advantage of the newly established clustered regularly interspaced short palindromic repeats/CRISPR-associated protein 9 (CRISPR/Cas9) system to achieve precise modification of the genome. After demonstrating that the Talin protein is still fully functional after insertion of the tension sensor modules, forces across Talin were first quantified—as a proof of concept—in primary muscle fibers in vitro using fluorescence lifetime imaging microscopy (FLIM) to measure FRET. In a second step, forces transmitted by Talin at muscle attachments during flight muscle development were analyzed in detail in living pupae. We discovered that a surprisingly small proportion of Talin molecules at developing muscle attachments transmit forces at the same time (Paper I). Nevertheless, a large pool of Talin molecules need to be recruited to muscle attachment sites during development, as quantified by fluorescence correlation spectroscopy (FCS), to prepare for the forces generated by active muscle contractions in the adult fly. If the accumulation of Talin at flight muscle attachments is reduced during development by RNA interference (RNAi), the muscle attachments rupture in young adults, likely during the first flight attempts. In conclusion, recruitment of a high number of Talin molecules during development is physiologically relevant to enable the muscle to adapt to sudden changes in tissue forces, likely by dynamically sharing the load among the Talin molecules. This mechanical adaptation concept is important to ensure that the muscle-tendon connections are stable and last for a lifetime. During the course of the thesis, I also discovered that flight muscles contract spontaneously during development. Characterization of these contractions in wild-type animals compared to a knockdown condition provided a functional readout for myofibrillogenesis during development (Paper IV). Furthermore, a review article on the role of mechanical forces during muscle development (Paper II) and a video article explaining how to perform in vivo imaging in Drosophila pupae (Paper III) were published

Energy: A continuing bibliography with indexes

This bibliography lists 1096 reports, articles, and other documents introduced into the NASA Scientific and Technical Information System from April 1, 1979 through June 30, 1979

A History of Materials and Technologies Development

The purpose of the book is to provide the students with the text that presents an introductory knowledge about the development of materials and technologies and includes the most commonly available information on human development. The idea of the publication has been generated referring to the materials taken from the organic and non-organic evolution of nature. The suggested texts might be found a purposeful tool for the University students proceeding with studying engineering due to the fact that all subjects in this particular field more or less have to cover the history and development of the studied object. It is expected that studying different materials and technologies will help the students with a better understanding of driving forces, positive and negative consequences of technological development, etc