Arrays of indefinitely long uniform nanowires and nanotubes

Nanowires are arguably the most studied nanomaterial model to make functional devices and arrays. Although there is remarkable maturity in the chemical synthesis of complex nanowire structures, their integration and interfacing to macro systems with high yields and repeatability still require elaborate aligning, positioning and interfacing and post-synthesis techniques. Top-down fabrication methods for nanowire production, such as lithography and electrospinning, have not enjoyed comparable growth. Here we report a new thermal size-reduction process to produce well-ordered, globally oriented, indefinitely long nanowire and nanotube arrays with different materials. The new technique involves iterative co-drawing of hermetically sealed multimaterials in compatible polymer matrices similar to fibre drawing. Globally oriented, endlessly parallel, axially and radially uniform semiconducting and piezoelectric nanowire and nanotube arrays hundreds of metres long, with nanowire diameters less than 15ĝ€‰nm, are obtained. The resulting nanostructures are sealed inside a flexible substrate, facilitating the handling of and electrical contacting to the nanowires. Inexpensive, high-throughput, multimaterial nanowire arrays pave the way for applications including nanowire-based large-area flexible sensor platforms, phase-changememory, nanostructure-enhanced photovoltaics, semiconductor nanophotonics, dielectric metamaterials,linear and nonlinear photonics and nanowire-enabled high-performance composites. © 2011 Macmillan Publishers Limited. All rights reserved

The interplay between plasma membrane and endoplasmic reticulum Ca2+ATPases in agonist-induced temporal Ca2+ dynamics

PubMedID: 25331516A change in the intracellular free Ca2+ concentration ([Ca2+]i) functions as a transmitter for signal transduction and shows a broad temporal pattern. Even genetically homogeneous cell types show different Ca2+ response patterns under permanent agonist stimulation. In Ca2+ signaling, the dynamics of the Ca2+ release from the Ca2+ channels during continuous agonist stimulation and the simultaneous effect of the pumps are unclear. In this study, the dynamic interaction of the Ca2+ ATPases in the plasma membrane (PMCA) and the endoplasmic reticulum membrane (SERCA) during continuous ACh stimulation is monitored using Fluo-3 and Fura-2 loaded HEK 293 cells. We characterize Ca2+ release patterns at the sub-maximal and maximal stimulation doses in the absence of extracellular Ca2+. We analyze the responses regarding their types, oscillation frequency and response times. La3+ (PMCA blocker) do not change the frequency and time courses in sub-maximal ACh treatment, while with the maximal stimulation oscillation frequency increase as oscillations superimpose on robust release, and response time of [Ca2+]i is elongated. A similar effect of La3+ is observed in quantal Ca2+ release phenomenon. In the presence of CPA, a SERCA blocker, oscillations are completely abolished, but response time does not change. We also observe that during continuous receptor stimulation, Ca2+ release do not cease. These data may suggest that Ca2+ release continues during agonist stimulation, but SERCA and PMCA form a new steady state and return [Ca2+]i to its physiological concentration. © 2014, Springer Science+Business Media New York

The arterial distribution and size of greater omentum

The greater omentum (omentum gastrocolica) is a filmy apron draped over the transverse colon and coils of the small intestine. Clinical importance of the omentum have increased in recent years as it is a unique structure being highly vascular. Intact omentum has been used for a variety of clinical reasons which included attempts to increase blood flow to the ischemic heart, brain and legs; to prevent or repair vesicovaginal fistulas; to protect at operation previously irradiated pelvic organs at operation; to treat lymphedema and hydrocephalus; to repair radionecrosis of the chest wall or flexion creases for reconstruction of the breast and to protect a previously irradiated carotid artery after radical neck dissection. The arterial structure of omentum influences the manner in which the omentum can be a lengthened. Also, it is important to know the omental limits before laparotomy. The main aim of this research was to determine the range of lenght and width of omentum and then to correlate them with the height of the the person present. Thus one is able to predict the size and limits of omentum laparotomy. In this study, involving a series of 107 cases, the size of omentum was determined and the types of vascularity were assessed. Correlations between height and omental width, patients' height and omental length were calculated