2,893 research outputs found
Effect of Puromycin on Mitotic Index, Amino Acid Incorporation and Dna Synthesis of Epidermal Cells
Puromycin 200 mg/kg given systemically will block DNA synthesis, amino acid incorporation and mitosis in the epidermis of the baby rat. Topically applied solutions of 1% puromycin did not have any effect on uptake of H3 thymidine or on mitosis of the epidermal cells. H3-puromycin given intraperitoneally was demonstrated in the epidermal cells by radioautographs but no evidence of labeling of epidermal cells was found by topical application
Using a White-Collar Profession in accounting courses: Approaches to addressing diversity
Accounting educators no doubt agree that diversity is an important and much neglected part of accounting education. They further recognize that it is difficult to incorporate this important topic into the accounting curriculum. This paper describes the efforts of various professors to expose business and accounting students to the evolution of diversity issues related to the accounting profession by using the book A White-Collar Profession [Hammond, 2002]. A White-Collar Profession: African-American CPAs Since 1921 is a seminal work which presents a history of the profession as it relates to African-American CPAs and documents the individual struggles of many of the first one hundred blacks to become certified. This paper describes efforts of faculty at four different colleges to utilize this book in their teaching of accounting. Instructors found that students not only developed an enhanced awareness about the history of the accounting profession, but that other educational objectives were advanced, such as improved communication and critical thinking skills, increased social awareness, and empathy for others. African-American students, in particular, embraced the people in the book as role models, while most every student saw the characters as heroic in a day when the accounting profession is badly in need of role models and heroes. This is encouraging given the profession\u27s concern with diversity and the attention and resources directed at increasing the number of minorities entering the profession
A Non-Standard String Embedding of E8
An algorithm to systematically and efficiently generate free fermionic
heterotic string models was recently introduced. This algorithm has been
adopted by the Free Fermionic Model Construction (FFMC) program at Baylor
University. As its first application, the algorithm is being applied to
systematically generate the complete set of free fermionic heterotic string
models with untwisted left-moving (worldsheet supersymmetric) sectors, up to
continually advancing Layer and Order. Statistical analysis of this study will
be reported in the near future. However, in a series of separate notes we will
be reporting some of the more interesting models that appear along the way. In
this, our first such note, we reveal a different string embedding of E8 than is
standard. That is, rather than realize E8 via an SO(16) embedding, 248 = 120 +
128, we realize it via an SU(9) embedding, 248 = 80 + 84 + 84-bar. This is
obtained in a Layer 1, Order 6 model for which modular invariance itself
dictates a gravitino sector accompany the gauge sector.Comment: Standard Latex, 7 page
High Resolution Chandra Spectroscopy of Gamma Cassiopeia (B0.5IVe)
gamma Cas has long been famous for its unique hard X-ray characteristics. We
report herein on a 53 ks Chandra HETGS observation of this target. An
inspection of our spectrum shows that it is quite atypical for a massive star,
with abnormally weak Fe XXV, XXVI lines, Ly-alpha lines of H-like species from
Fe XVII, XXIII, XXIV, S XVI, Si XIV, Mg XII, Ne X, O VII, VIII, and N VII.
Also, line ratios of the rif-triplet of for a few He-like ions XVII are
consistent with the dominance of collisional atomic processes. Yet, the
presence of Fe and Si fluorescence K features indicates that photoionization
also occurs in nearby cold gas. The line profiles indicate a mean velocity at
rest and a broadening of 500 km/s. A global fitting analysis of the line and
continuum spectrum finds that there are 3-4 plasma emission components. The
dominant hot (12 keV) component and has a Fe abundance of 0.22 solar. Some
fraction of this component (10-30%) is heavily absorbed. The other 2-3
components, with temperatures 0.1, 0.4, 3 keV, are "warm," have a nearly solar
composition, a lower column absorption, and are responsible for most other
emission lines. The strength of the fluorescence features and the dual-column
absorption model for the hot plasma component suggest the presence near the hot
sites of a cold gas structure with a column density of 10^23 cm^-2. Since this
value is consistent with theoretical estimates of the vertical disk column of
this star, these attributes suggest that the X-rays originate near the star or
disk. It is possible that the Fe anomaly in the hot component is related to the
First Ionization Potential effect found in coronal structures around active
cool stars. This would be yet another indication that the X-rays -rays are
produced in the immediate vicinity of the Be star.Comment: 32 pages, 4 figures (Fig. 3 colorized.) To be published in 01/10/04
Astrophysical Journal, Main Journal; included figures and updated formattin
Structure formation by cosmic strings with a cosmological constant
Final published version.Comment: 4 Page
Operando Ultrasonic Monitoring of the Internal Temperature of Lithium-ion Batteries for the Detection and Prevention of Thermal Runaway
Lithium-ion batteries (LIBs) play an integral role in powering various applications, from consumer electronics to stationary storage, and notably in the accelerating domain of electric vehicles (EVs). Despite their widespread adoption and numerous benefits, safety issues are of major concern, especially with the surge in their utilization and increasing proliferation of second-life cells, particularly in domestic energy storage applications. A critical concern revolves around susceptibility to thermal runaway, leading to highly hazardous and challenging-to-contain fires. Addressing these concerns necessitates effective methods to monitor internal temperature dynamics within lithium-ion cells swiftly and cost-effectively, alongside a need to develop prognostic techniques to pre-empt thermal runaway occurrences. This study presents an innovative approach that uses ultrasound analysis to track intricate internal temperature fluctuations and gradients within cells. Moreover, an efficient multi-stage warning system is proposed that is designed to proactively prevent thermal runaway events. The findings offer promising avenues for enhancing the safety and reliability of lithium-ion battery systems
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