Abstract: Methods are disclosed which combine electrospinning and a sacrificial template, such as with additive manufacturing (AM), to produce fibrous microvascular scaffolds which are biodegradable, porous, and easily handled. In one example, a process for fabricating a fibrous network construct is disclosed. The method includes electrospinning a first layer of fibrous material; printing a micropatterned sacrificial template; transferring the micropatterned sacrificial template onto the electrospun fibers; electrospinning a second layer of fibrous biomaterial onto the micropatterned sacrificial template thereby encapsulating the template and generating a construct with two layers; and removing the sacrificial template, producing a fibrous construct with channels or microstructures formed therein. Also disclosed are fibrous constructs and scaffolds produced by the provided methods.

Abstract: A frequency hopping radio communications system has a plurality of radios each incorporating a transmitter and a receiver. When a radio is not transmitting or receiving, a switch switches it into a mode in which it monitors the signal strength in each of the available hop channels so as to assess the level of interference, and selects a subset of the total number of channels, those having the lowest interference level. The identities of this subset of channels are stored in a store. When the radio is to transmit a message, it first transmits the identities of the subset of channels stored in the store--using the full number of hop channels (the information being transmitted with sufficient redundancy to overcome likely interference). The receiving radios receive the identities of the subset of channels. The transmitting radio then transmits, pseudo-randomly, on this subset only and each of the receivers receives on this subset only.