A mathematical and analytical model of plastic forming in such extruder was developed and the results were nondimensional-normalized. To validate the mathematical solutions experiments based on LDPE were carried out and the experimental vibration amplitude and vibration frequency curve was obtained. Three conclusions can be drawn herein:

(1) the experimental results hold a good agreement with the calculations, and thus the feasibility of the proposed model is validated; (2) the possibility of resonance closely relates to polymer melt viscosity, rotating speed, and geometry parameters of the screw; (3) resonance of the tri-screw extruder is seldom observed under normal conditions and www.selleckchem.com/products/17-DMAG,Hydrochloride-Salt.html there exists an inverse correlationship between vibration frequency and amplitude. (C) 2011 Wiley Periodicals, Inc. J Appl Polym Sci 122: 1778-1784, 2011″
“The Kapitza resistance across a Si bicrystal interface was measured using a pump

probe optical technique. This approach, termed time resolved thermal wave microscopy (TRTWM), uses ultrafast laser pulses to image lateral thermal transport in bare semiconductors. The sample geometry is selleck that of a Si bicrystal with the vertically oriented boundary intersecting the sample surface. High resolution transmission electron microscopy of the boundary region revealed a thin SiO2 layer at the interface. By comparing experimental results with a continuum thermal transport model the Kapitza resistance between the Si and SiO2 was estimated to be 2.3 x 10(-9) m(2)K/W. (C) 2011 American Institute of Physics. [doi:10.1063/1.3573511]“
“Human papillomavirus (HPV) is associated with the development of a subset of head and neck cancers arising in the oropharynx, which includes the tonsils, base of tongue and soft palate. HPV-associated oropharyngeal cancer (OPC) seems to be rapidly increasing SNS-032 in incidence in many countries, including the USA, Sweden and Greece, and is known to affect younger patients who are less likely to have been exposed to the carcinogenic effects

of tobacco and alcohol than their HPV-negative counterparts. There is accumulating evidence from prospective studies that HPV-positive OPC responds better to treatment, including chemotherapy and radiotherapy, than HPV-negative OPC, and that patients with HPV-positive disease have excellent long-term survival rates. To date, patients with HPV-positive and HPV-negative OPC are managed according to common treatment protocols; this may no longer be appropriate in an age when the delivery of targeted treatment, tailored to individual tumour and patient characteristics, is becoming a reality. This review summarises our current understanding of HPV-positive OPC, drawing parallels from the role of HPV in the development of cervical cancer.