Electron Interactions and Transport Between Coupled Quantum Hall Edges

We examine the effects of electron-electron interactions on transport between edge states in a multilayer integer quantum Hall system. The edge states of such a system, coupled by interlayer tunneling, form a two-dimensional, chiral metal at the sample surface. We calculate the temperature-dependent conductivity and the amplitude of conductance fluctuations in this chiral metal, treating Coulomb interactions and disorder exactly in the weak-tunneling limit. We find that the conductivity increases with increasing temperature, as observed in recent experiments, and we show that the correlation length characterising conductance fluctuations varies inversely with temperature.Comment: 4 pages, 2 figures, typos corrected, Ref. 17 added, minor changes made for publicatio

Co-ordinated rabbit control using 1080

In the coming season it is proposed to poison with 1080 most of the rabbit-infested areas south of the East-West railway and comprising chiefly the South-West and Great Southern areas. The Agriculture Protection Board will be employing 14 Rabbit Control Units each consisting of two men, a Land Rover and caravan. These will be grouped in two main batches of six each, with the other two kept in reserve to do small isolated areas as required

Laboratory Information Management System Chain of Custody: Reliability and Security

A chain of custody (COC) is required in many laboratories that handle forensics, drugs of abuse, environmental, clinical, and DNA testing, as well as other laboratories that want to assure reliability of reported results. Maintaining a dependable COC can be laborious, but with the recent establishment of the criteria for electronic records and signatures by US regulatory agencies, laboratory information management systems (LIMSs) are now being developed to fully automate COCs. The extent of automation and of data reliability can vary, and FDA- and EPA-compliant electronic signatures and system security are rare

A novel selective 11b-hydroxysteroid dehydrogenase type 1 inhibitor prevents human adipogenesis.

Glucocorticoid excess increases fat mass, preferentially within omental depots; yet circulating cortisol concentrations are normal in most patients with metabolic syndrome (MS). At a pre-receptor level, 11b-hydroxysteroid dehydrogenase type 1 (11b-HSD1) activates cortisol from cortisone locally within adipose tissue, and inhibition of 11b-HSD1 in liver and adipose tissue has been proposed as a novel therapy to treat MS by reducing hepatic glucose output and adiposity. Using a transformed human subcutaneous preadipocyte cell line (Chub-S7) and human primary preadipocytes, we have defined the role of glucocorticoids and 11b-HSD1 in regulating adipose tissue differentiation. Human cells were differentiated with 1.0 mM cortisol (F), or cortisone (E) with or without 100 nM of a highly selective 11b-HSD1 inhibitor PF-877423. 11b-HSD1 mRNA expression increased across adipocyte differentiation (P!0.001, nZ4), which was paralleled by an increase in 11b-HSD1 oxo-reductase activity (from nil on day 0 to 5.9G1.9 pmol/mg per h on day 16,P!0.01, nZ7). Cortisone enhanced adipocyte differentiation; fatty acid-binding protein 4 expression increased 312-fold (P!0.001) and glycerol-3-phosphate dehydrogenase 47-fold (P!0.001) versus controls. This was abolished by co-incubation with PF-877423. In addition, cellular lipid content decreased significantly. These findings were confirmed in the primary cultures of human subcutaneous preadipocytes. The increase in 11b-HSD1 mRNA expression and activity is essential for the induction of human adipogenesis. Blocking adipogenesis with a novel and specific 11b-HSD1 inhibitor may represent a novel approach to treat obesity in patients with MS

Turning Fake Data into Fake News: AI Training Set as a Trojan Horse of Misinformation

Generative artificial intelligence (AI) offers tremendous benefits to society. However, these benefits must be carefully weighed against the societal damage AI can also cause. Dangers posed by inaccurate training sets have been raised by many authors. These include racial discrimination, sexual bias, and other pernicious forms of misinformation. One remedy to such problems is to ensure that training sets used to teach AI models are correct and that the data upon which they rely are accurate. An assumption behind this correction is that data inaccuracies are inadvertent mistakes. However, a darker possibility exists: the deliberate seeding of training sets with inaccurate information for the purpose of skewing the output of AI models toward misinformation. As United States Supreme Court Justice Oliver Wendell Holmes, Jr., suggested, laws are not written for the “good man,” because good people will tend to obey moral and legal principles in manners consistent with a well-functioning society even in the absence of formal laws. Rather, Justice Holmes proposed, that laws should be written with the “bad man” in mind, because bad people will push the limits of acceptable behavior, engaging in cheating, dishonesty, crime, and other societally- damaging practices, unless constrained by carefully-designed laws and their accompanying penalties. This Article raises the spectre of the deliberate sabotage of training sets used to train AI models, with the purpose of perverting the outputs of such models. Examples include fostering revisionist histories, unjustly harming or rehabilitating the reputations of people, companies, or institutions, or even promoting as true ideas that are not. Strategic and clever efforts to introduce ideas into training sets that later manifest themselves as facts could aid and abet fraud, libel, slander, or the creation of “truth,” the belief in which promote the interests of particular individuals or groups. Imagine, for example, a first investor who buys grapefruit futures, who then seeds training sets with the idea that grapefruits will become the new gold, with the result that later prospective investors who consult AI models for investment advice are informed that they should invest in grapefruit, enriching the first investor. Or, consider a malevolent political movement that hopes to rehabilitate the reputation of an abhorrent leader; if done effectively, this movement could seed training sets with sympathetic information about this leader, resulting in positive portrayals of this leader in the future outputs of trained AI models. This Article adopts the cautious attitude necessitated by Justice Holmes’ bad man, applying it to proactively stopping, or retroactively punishing and correcting, deliberate attempts to subvert the training sets of AI models. It offers legal approaches drawn from doctrines ranging from fraud, nuisance, libel, and slander, to misappropriation, privacy, and right of publicity. It balances these with protections for speech afforded by the First Amendment and other doctrines of free speech. The result is the first comprehensive attempt to prevent, respond to, and correct deliberate attempts to subvert training sets of AI models for malicious purposes

Nuclear Magnetic Resonance and Hyperfine Structure

Contains reports on four research projects

Design, fabrication, and delivery of a charge injection device as a stellar tracking device

Six 128 x 128 CID imagers fabricated on bulk silicon and with thin polysilicon upper-level electrodes were tested in a star tracking mode. Noise and spectral response were measured as a function of temperature over the range of +25 C to -40 C. Noise at 0 C and below was less than 40 rms carriers/pixel for all devices at an effective noise bandwidth of 150 Hz. Quantum yield for all devices averaged 40% from 0.4 to 1.0 microns with no measurable temperature dependence. Extrapolating from these performance parameters to those of a large (400 x 400) array and accounting for design and processing improvements, indicates that the larger array would show a further improvement in noise performance -- on the order of 25 carriers. A preliminary evaluation of the projected performance of the 400 x 400 array and a representative set of star sensor requirements indicates that the CID has excellent potential as a stellar tracking device

Nuclear Magnetic Resonance and Hyperfine Structure

Contains reports on three research projects