Drexel University

About: Drexel University is a education organization based out in Philadelphia, Pennsylvania, United States. It is known for research contribution in the topics: Population & Poison control. The organization has 26770 authors who have published 51438 publications receiving 1949443 citations. The organization is also known as: Drexel & Drexel Institute.

Power conversion efficiency exceeding the Shockley–Queisser limit in a ferroelectric insulator

Abstract: The Shockley–Queisser limit for solar cells is overcome in the ferroelectric insulator BaTiO3.

Cyclins, cyclin-dependent kinases and cdk inhibitors: implications in cell cycle control and cancer.

Abstract: A significant portion of cell scientific literature published is dedicated to describing the cloning, the link to cancer, or the characterization of proteins involved in the progression of the cell cycle. With this abundance of information, the cascading pathways of molecular events that occur in the cell cycle are proving to be exceedingly complicated. Originally, the sole regulator of the fission yeast cells division cycle, cdc2, was thought to also regulate mammalian cell cycles in the same manner. However, mammalian cdc2 has now been joined by seven well-characterized relatives acting at distinct points in the cell cycle. These kinases are activated by larger proteins called cyclins, named with respect to their cyclical expression and degradation. Therefore, the catalytic subunits of these complexes are named cyclin-dependent kinases (cdks). In the event that the cell must stop normal cycling behavior, a number of cdk inhibitors, which have only begun to be characterized, function in inhibiting the kinase ability of cdks, among other nonproliferative acts. The external environment manipulates cellular proliferation and differentiation by stimulating or inhibiting certain signal transduction pathways. However, each component of the cell cycle machinery, as they are the final executors in cell division, has the potential to elicit or to contribute to a neoplastic phenotype. This review focuses on the characterization of each member of the cell cycle protein family and also addresses the potential role each plays in cancer.

The palliation of brain metastases in a favorable patient population: A randomized clinical trial by the radiation therapy oncology group

Abstract: The palliative effectiveness of a short, intensive course of brain irradiation (3000 rad in 2 weeks) was compared to that of a high-dose course (5000 rad in 4 weeks) in a randomized RTOG clinical trial. Eighty percent of the 255 evaluable patients had lung primaries, 7% breast, and 13% other or unknown primaries. Patients with evidence of extra-cranial metastases, uncontrolled primaries, or Class IV Neurologic Function (NFIV) were excluded. Forty-one percent of NFII and 71 % of NFIV patients improved in neurologic function class. For NFII patients, a significantly greater improvement rate was obtained with the short course than with the long course. Otherwise there were no significant differences between the two regimens with respect to palliation of symptoms, improvement rate, median time to progression, cause of death, or median survival. We conclude that 3000 rad in two weeks is at least as effective as 5000 rad in four weeks in the palliation of brain metastases, even in this relatively favorable patient population.

Salt-Templated Synthesis of 2D Metallic MoN and Other Nitrides

Abstract: Two-dimensional (2D) transition-metal nitrides just recently entered the research arena, but already offer a potential for high-rate energy storage, which is needed for portable/wearable electronics and many other applications. However, a lack of efficient and high-yield synthesis methods for 2D metal nitrides has been a major bottleneck for the manufacturing of those potentially very important materials, and only MoN, Ti4N3, and GaN have been reported so far. Here we report a scalable method that uses reduction of 2D hexagonal oxides in ammonia to produce 2D nitrides, such as MoN. MoN nanosheets with subnanometer thickness have been studied in depth. Both theoretical calculation and experiments demonstrate the metallic nature of 2D MoN. The hydrophilic restacked 2D MoN film exhibits a very high volumetric capacitance of 928 F cm–3 in sulfuric acid electrolyte with an excellent rate performance. We expect that the synthesis of metallic 2D MoN and two other nitrides (W2N and V2N) demonstrated here will pro...