A study of the motor unit action potential by means of computer simulation

In order to study the motor unit action potential a computer simulation model was developed. It is based on the superposition of single muscle fibre potentials of the fibres belonging to the motor unit. The parameters which characterize each fibre (spatial position, diameter, and a dispersion of arrival time of the potential at the electrode) are chosen from statistical distributions which can be derived from anatomical and physiological data. The electrode type, position and dimensions can be specified. Simulated motor unit action potentials are presented in the time and frequency domain. The simulation results refer to (1) the influence of the electrode position and dimensions with respect to the motor unit territory, (2) the meaning of this model for the study of pathological phenomena, (3) the variability of some parameters characterizing the motor unit, (4) the selectivity of uni- and bipolar electrodes and finally (5) the influence of the geometrical situation of the motor end-plates within the muscle, on the shape of motor unit action potentials

Colours of fruit and vegetables and 10-year incidence of CHD

The colours of the edible part of fruit and vegetables indicate the presence of specific micronutrients and phytochemicals. The extent to which fruit and vegetable colour groups contribute to CHD protection is unknown. We therefore examined the associations between fruit and vegetables of different colours and their subgroups and 10-year CHD incidence. We used data from a prospective population-based cohort including 20 069 men and women aged 20–65 years who were enrolled between 1993 and 1997. Participants were free of CVD at baseline and completed a validated 178-item FFQ. Hazard ratios (HR) for the association between green, orange/yellow, red/purple, white fruit and vegetables and their subgroups with CHD were calculated using multivariable Cox proportional hazards models. During 10 years of follow-up, 245 incident cases of CHD were documented. For each 25 g/d increase in the intake of the sum of all four colours of fruit and vegetables, a borderline significant association with incident CHD was found (HR 0·98; 95 % CI 0·97, 1·01). No clear associations were found for the colour groups separately. However, each 25 g/d increase in the intake of deep orange fruit and vegetables was inversely associated with CHD (HR 0·74; 95 % CI 0·55, 1·00). Carrots, their largest contributor (60 %), were associated with a 32 % lower risk of CHD (HR 0·68; 95 % CI 0·48, 0·98). In conclusion, though no clear associations were found for the four colour groups with CHD, a higher intake of deep orange fruit and vegetables and especially carrots may protect against CH

Quantum dot / optical protein bio-nano hybrid system biosensing

The integration of novel nanomaterials with highly-functional biological molecules has advanced multiple fields including electronics, sensing, imaging, and energy harvesting. This work focuses on the creation of a new type of bio-nano hybrid substrate for military biosensing applications. Specifically it is shown that the nano-scale interactions of the optical protein bacteriorhodopsin and colloidal semiconductor quantum dots can be utilized as a generic sensing substrate. This work spans from the basic creation of the protein to its application in a novel biosensing system. The functionality of this sensor design originates from the unique interactions between the quantum dot and bacteriorhodopsin molecule when in nanoscale proximity. A direct energy transfer relationship has been established between coreshell quantum dots and the optical protein bacteriorhodopsin that substantially enhances the protein’s native photovoltaic capabilities. This energy transfer phenomena is largely distance dependent, in the sub-10nm realm, and is characterized experimentally at multiple separation distances. Experimental results on the energy transfer efficiency in this hybrid system correlate closely to theoretical predictions. Deposition of the hybrid system with nano-scale control has allowed for the utilization of this energy transfer phenomena as a modulation point for a functional biosensor prototype. This work reveals that quantum dots have the ability to activate the bacteriorhodopsin photocycle through both photonic and non-photonic energy transfer mechanisms. By altering the energy transferred to the bacteriorhodopsin molecule from the quantum dot, the electrical output of the protein can be modulated. A biosensing prototype was created in which the energy transfer relationship is altered upon target binding, demonstrating the applicability of a quantum dot/bacteriorhodopsin hybrid system for sensor applications. The electrical nature of this sensing substrate will allow for its efficient integration into a nanoelectronics array form, potentially leading to a small-low power sensing platform for remote toxin detection applications

Mini-Symposium: Best practices for REU programs and UNL

If you want to learn how to run an REU (Research Experience for Undergraduates) program (or to make your REU program run more smoothly), then this is your opportunity to ask questions. The presentation will begin with 5-min talks from five REU program coordinators. These coordinators run a wide range of programs and have experience ranging from 1 year to 12 years. They will mention things such as how many applicants their program receives, how they review those files, an outline of the non-research portion of their summer program, and what sorts of outcomes they collect so they can report them to NSF. Then, the coordinators will form a panel to answer questions. Shannon Bartelt-Hunt, Department of Civil Engineering Mark Griep, Department of Chemistry Don Becker, Redox Biolog

CRIMINAL LAW-A STUDY OF STATUTORY BLACKMAIL AND EXTORTION IN THE SEVERAL STATES

In attempting to define the crime of extortion or blackmail, it must be pointed out at the outset that there is a technical crime known as extortion, which stems from the common law, and there is another statutory crime which may be called extortion or blackmail, this latter crime being what the lawyer and laymen usually refer to by the term blackmail. Extortion at common law was the unlawful taking by an officer, by color of his office, of any money or thing of value that was not due him, or more than was due, or before it was due. To state the case simply, if any tax official demanded taxes of a citizen before they were due, that official was guilty of extortion. A private citizen could not be guilty of this crime. The scope of that common law offense was enlarged by statute to include any obtaining by any person of property of another with his consent through a wrongful threat to do injury. And so by enlarging the scope of the common law offense a new statutory offense was in fact created. It is with this statutory offense, whether it is called extortion or blackmail, or even if it does not have a name, that this paper deals. There are many variations in the statutes defining this broader statutory offense, which the author will hereinafter refer to as blackmail. If the reader were to pick a few states at random and look up the law in those states, he would probably find that no two of them are alike in all their requirements. However, there are certain similarities in various of the state statutes which fit into certain patterns; and upon taking an overall view of all the statutes, modified categorizations may be set forth. It is the purpose of the author to present this overall picture by classifying and comparing the express language of the statutes of all the jurisdictions within the United States, interposing at times comments on the broad, and sometimes ambiguous language used by the legislators. The crime of extortion by a public official is not within the scope of this paper; neither are threats which are punishable even though no property is demanded

Mini-Symposium: Best practices for REU programs and UNL

If you want to learn how to run an REU (Research Experience for Undergraduates) program (or to make your REU program run more smoothly), then this is your opportunity to ask questions. The presentation will begin with 5-min talks from five REU program coordinators. These coordinators run a wide range of programs and have experience ranging from 1 year to 12 years. They will mention things such as how many applicants their program receives, how they review those files, an outline of the non-research portion of their summer program, and what sorts of outcomes they collect so they can report them to NSF. Then, the coordinators will form a panel to answer questions. Shannon Bartelt-Hunt, Department of Civil Engineering Mark Griep, Department of Chemistry Don Becker, Redox Biolog