Isolated porcine thyroid cells reorganize in culture into various types of multicellular structure, which differ in the orientation of cell polarity and in the surface of the cell layer accessible to molecules present in the culture medium. The types of structure are: (1) follicles: the basal pole is oriented toward the medium; (2) inside-out follicles or monolayers: the apical pole is facing t...

This week, we’ll talk about the lowest layer of the 5-layer stack: the physical layer. This is the layer that deals with the ground realities of transmitting data on a cable or an antenna. It is also the layer that is closer to electrical engineering than computer science. Why are we learning about this layer? It’s not because it is going to be particularly useful in a job that you take up afte...

The demand for higher data rate has spurred the adoption of multiple-input multiple-output (MIMO) transmission techniques in IEEE 802.11 products. MIMO techniques provide an additional spatial dimension that can significantly increase the channel capacity. A number of multiuser MIMO system have been proposed, where the multiple antenna at the physical layer are employed for multiuser access, al...

Five strains of type III pneumococcus have been shown to possess wide capsular slime layers during the logarithmic phase of growth in serum broth. The slime layer stains metachromatically with methylene blue and can be visualized under the electron microscope as a fuzzy halo which extends well beyond the surace of the capsule proper and causes centrifugates of the organism to be of extremely la...

An apparatus has been developed which permits the cultivation of a large number of tissue fragments in a large quantity of culture medium. The tissue fragments are cultivated in a thin layer of well oxygenated and constantly circulating medium.

The analysis and optimal design of a multi-layered microstrip sensor for measuring moisture content of ricegrain are described. The microstrip sensing structure consists of three layers: substrate, protective layer and semi-infinite grain medium. The effective dielectric constant, characteristic impedance and attenuation or insertion loss of this structure are calculated at various moisture con...

In this paper we study the impact of the medium access control (MAC) layer and the routing layer on the performance of a multi-hop wireless network. At the medium access control layer, we argue that the notion of per-node fairness employed by the IEEE 802.11 standard is not suitable for a multi-hop wireless network where flows traverse multiple hops. We propose a new MAC protocol that supports ...

High data rate, reliable wireless access has been the focus in the design of the future wireless broadband communications. The wireless access is increasingly becoming data centric, and has to meet the requirements of a wide array of traffic ranging from voice, multimedia, and other real-time applications. The technology that work behind the scenes to make all this happen is constantly improvin...

A preliminary theory is established for the stability of e visooelastio leyer sandwiched in an infinitely extended medium of another visooelastio materiel when s compressive force is acting in a direction parallel with the layer. The instability is menifested by e folding of the layer. It is shown that in general there exists e lower and & higher critical load between which folding occurs at a ...