Wide-band random excitation of beams and rectangular plates coupled to discrete substructures

Formulation of the title problem using the Green's function of the beam or plate allows solution by the methods of classical modal analysis. These are briefly reviewed in this context and the necessary results are stated for both classically and nonclassically damped systems, the mean square response to stationary excitation being obtained in terms of spectral integrals. Some cases in which these can be evaluated analytically are examined.     

Requirement of Drosophila NF1 for activation of adenylyl cyclase by PACAP38-like neuropeptides

The human neurofibromatosis type 1 (NF1) tumor suppressor protein functions as a Ras-specific guanosine triphosphatase-activating protein, but the identity of Ras- mediated pathways modulated by NF1 remains unknown. A study of Drosophila NF1 mutants revealed that NF1 is essential for the cellular response to the neuropeptide PACAP38 (pituitary adenylyl cyclase-activating polypeptide) at the neuromuscular junction. The peptide induced a 100-fold enhancement of potassium currents by activating the Ras-Raf and adenylyl cyclase-adenosine 3',5'-monophosphate (cAMP) pathways. This response was eliminated in NF1 mutants. NF1 appears to regulate the rutabaga-encoded adenylyl cyclase rather than the Ras-Raf pathway. Moreover, the NF1 defect was rescued by the exposure of cells to pharmacological treatment that increased concentrations of cAMP.     

Thoracic surgery techniques of Serefeddin Sabuncuo?lu in the fifteenth century

Serefeddin Sabuncuo?lu (1385 to 1470?) is known to be the author of the first surgery textbook, namely Cerrahiyyet'ül Haniyye (Imperial Surgery), written in Turkish in 1465. It is the first book to contain colored illustrations of surgical procedures, incisions, and instruments in the Turkish-Islamic medical literature. He was the first man to illustrate and mention introduction of a tube into the pharynx and upper esophagus, removal of foreign bodies in the esophagus by special instruments of his own design, and use of a silver ringlet in a man after tracheotomy. He also described and illustrated reduction of sternal fractures, thoracic puncture through the intercostal space for drainage of empyema cavities, and treatment of rib fractures that have severed the diaphragm. He was a humble, curious, and intelligent surgeon, and also a calligrapher and a miniature artist.     

Metastatic phenotype correlates with high expression of membrane-associated complete beta-human chorionic gonadotropin in vivo

BACKGROUND: Investigations using living human cancer cells and the nude mouse model were conducted to evaluate the expression of human chorionic gonadotropin (hCG) in various cancers grown in vitro and in vivo. The aim was to determine whether membrane-associated hCG in any of its forms is a characteristic metastatic marker, and at what levels or ratios. METHODS: Human cancer cell lines known to produce tumors that metastasize spontaneously when grown in nude mice (n = 4) were compared with those that do not produce such tumors (n = 4) using analytical (quantitative) flow cytometry. Monoclonal antibodies directed to epitopes of intact hCG (hCG-holo) and its subunits, including beta-human chorionic gonadotropin with its carboxy-terminal peptide (hCG beta-CTP), allowed for the determination of hCG beta-CTP/hCG-holo ratios. RESULTS: No significant difference in hCG beta-CTP/hCG-holo ratios was found between the cultured human cancer cells that do not metastasize spontaneously (ratio = 2.39) and those that do (ratio = 2.13), and no difference was seen in their growth rate in nude mice. However, the cells isolated from tumors that do not metastasize spontaneously showed a decrease in their ratios to values less than 1. They reverted to their original values after reestablishment in culture and subsequent passages. In contrast, the ratios shown by cells isolated from tumors that metastasize spontaneously increased to 3 to 6 times their original values in culture, then reverted to their original values after reestablishment in culture and subsequent passages. CONCLUSIONS: To our knowledge, these data demonstrate the following for the first time: 1) There is a direct in vivo correlation between human cancer cells that metastasize spontaneously in nude mice and the expression of membrane-associated complete hCG beta (hCG beta-CTP); and the correlation identifies this molecule as a characteristic metastatic phenotype marker. 2) The marked ratio variations under different conditions indicate that the metastatic phenotype is an unstable event. 3) Growth and local invasion in vivo correlates with the expression of hCG-holo.     

Collective self-esteem as a moderator of the frog-pond effect in reactions to performance feedback.

Individuals who perform well within an unsuccessful group have more favorable reactions than equally capable individuals who perform poorly within a successful group. This frog-pond effect appears to occur because people focus on their relative performance standing within their group rather than on their group's overall performance level. It was hypothesized that this effect would be attenuated among people who value their social groups highly because they should be more likely than their counterparts to take into account their group's performance level when evaluating themselves. Four studies supported this reasoning. The frog-pond effect was strongest among individuals with lower collective self-esteem, an individualistic cultural heritage, or a weaker bond toward a particular social group. (PsycINFO Database Record (c) 2010 APA, all rights reserved)