Ionization Studies of Nitrogen & Nitrogen-Sulfur Hexaflouride Mixtures

Ionization measurements as a function of concentration and pressure have been made in nitrogen and nitrogen-sulfur hexafluoride gas mixtures containing either cyclopropane, ethylene, propylene, acetylene, ethane, or impurity. These studies have been made to understanding of the gas kinetics involved propane as contribute in nitrogen an to the and nitrogen-sulfur hexafluoride laser systems. Impurity gases were chosen on the basis of their ionization potentials relative to the C3πu state in nitrogen that is responsible for the lasing action. Analysis of the data indicated that a Jesse effect exists for those impurity gases whose ionization potentials lie below the C3πu state of nitrogen and that the effect is enhanced by the addition of SF6. The ionization was found to be dependent on pressure for mixtures containing SF6

Risk Factors of the First Febrile Seizures in Iranian Children

Objective. Febrile seizures are the most common type of convulsion in children. The identification of influencing factors on incidence of the first febrile seizures is of prime priority. The aim of this study was to identify the risk factors of the first febrile seizures in Iranian children. Methods. In this case-control study 80 children aged 9 month to 5 years with their first febrile seizures were compared with 80 children with fever without seizure based on different risk factors in 2007. Results. There was significant difference between two groups regarding the gender, family history of febrile seizures, breast-feeding duration, and the body temperature (P < .05). Conclusion. Our study showed that factors including the gender, family history of febrile seizures, breast-feeding duration, and the body temperature are among the risk factors in occurrence of the first febrile seizure. Preventive measures to remove such risk factors could lead to lower the incidence of febrile seizures

Datum transformation analysis for production part approval using 3D non-contact measurement

This paper presents a comprehensive dimensional validation methodology, known as datum transformation analysis (DTA). The DTA approach utilizes 3D non-contact (3DNC) measurement to obtain a full part dimensional representation at all critical matching interfaces of a part assembly to the vehicle. Next, a part measurement re-alignment process is applied to identify new positions for the assembly datum locators that optimize the overall product quality at these matching interfaces. Next, datum locations are adjusted at the component level (at the same physical location as the corresponding assembly) to improve mean conformance of the assembly dimensions. The adjustments to the datum locators at the component level are not necessarily made to improve component quality, but rather to optimize final part assembly. This DTA methodology is demonstrated using an automotive headlamp assembly. In this case study, we identify tooling rework moves using DTA to increase the percent of critical assembly dimensions whose mean values are within ±0.25 millimeters from 20% to 90%.Visteonhttp://deepblue.lib.umich.edu/bitstream/2027.42/61819/1/102172.pd

Field-effect-induced two-dimensional electron gas utilizing modulation-doped ohmic contacts

Modulation-doped AlGaAs/GaAs heterostructures are utilized extensively in the study of quantum transport in nanostructures, but charge fluctuations associated with remote ionized dopants often produce deleterious effects. Electric field-induced carrier systems offer an attractive alternative if certain challenges can be overcome. We demonstrate a field-effect transistor in which the active channel is locally devoid of modulation-doping, but silicon dopant atoms are retained in the ohmic contact region to facilitate reliable low-resistance contacts. A high quality two-dimensional electron gas is induced by a field-effect and is tunable over a wide range of density. Device design, fabrication, and low temperature (T=0.3 K) transport data are reported.Physic

Understanding the prion-like behavior of mutant p53 proteins in triple-negative breast cancer pathogenesis: The current therapeutic strategies and future directions

Breast cancer (BC) is viewed as a significant public health issue and is the primary cause of cancer-related deaths among women worldwide. Triple-negative breast cancer (TNBC) is a particularly aggressive subtype that predominantly affects young premenopausal women. The tumor suppressor p53 playsa vital role in the cellular response to DNA damage, and its loss or mutations are commonly present in many cancers, including BC. Recent evidence suggests that mutant p53 proteins can aggregate and form prion-like structures, which may contribute to the pathogenesis of different types of malignancies, such as BC. This review provides an overview of BC molecular subtypes, the epidemiology of TNBC, and the role of p53 in BC development. We also discuss the potential implications of prion-like aggregation in BC and highlight future research directions. Moreover, a comprehensive analysis of the current therapeutic approaches targeting p53 aggregates in BC treatment is presented. Strategies including small molecules, chaperone inhibitors, immunotherapy, CRISPR-Cas9, and siRNA are discussed, along with their potential benefits and drawbacks. The use of these approaches to inhibit p53 aggregation and degradation represents a promising target for cancer therapy. Future investigations into the efficacy of these approaches against various p53 mutations or binding to non-p53 proteins should be conducted to develop more effective and personalized therapies for BC treatment