The computer-aided design of nano-scaled digital circuits

The use of CMOS-based transistors to implement digital logic is the prevalent means of modern computation. It is, however, not the only means. Advances in nano-science and engineering demonstrate that nano-scale integrated circuits are in fact a viable technology for computation. The dominant means for information propagation in these devices is quantum tunneling - a phenomenon that is not wholly compatible with current design techniques. This paper is an explanation of one process used to both design and simulate digital logic circuits utilizing the topology of the hypercube. The aim of the paper is to demonstrate the ease of designing and implementing a streamlined design environment and to demonstrate the utility that such an environment affords the designer. The hypercube topology is used as the dominant example for constructing 3D circuits. In this topology, each device is required to operate as a doubly gated switch and computation is performed utilizing a concept similar to pass-gate technology. The paper details the software required to generate the logic circuit and the means of simulation. Each device of the structure is modeled using a non-linear state-space representation. The paper concludes with two examples of implementable technologies: single-electron transistors (wrap-gate structures with quantum dots), and endohederal fullerenes acting as gate switches

Anomalous suppression of the Bose glass at commensurate fillings in the disordered Bose-Hubbard model

We study the weakly disordered Bose-Hubbard model on a cubic lattice through a one-loop renormalization group analysis of the corresponding effective field theory which is explicitly derived by combining a strong-coupling expansion with a replica average over the disorder. The method is applied not only to generic uncorrelated on-site disorder but also to simultaneous hopping disorder correlated with the differences of adjacent disorder potentials. Such correlations are inherent in fine-grained optical speckle potentials used as a source of disorder in optical lattice experiments. As a result of strong coupling, the strength of the replica mixing disorder vertex, responsible for the emergence of a Bose glass, crucially depends on the chemical potential and the Hubbard repulsion and vanishes to leading order in the disorder at commensurate boson fillings. As a consequence, at such fillings a direct transition between the Mott-insulator and the superfluid in the presence of disorder cannot be excluded on the basis of a one-loop calculation. At incommensurate fillings, at a certain length scale, the Mott insulator will eventually become unstable towards the formation of a Boss glass. Phase diagrams as a function of the microscopic parameters are presented and the finite-size crossover between the Mott-insulating state and the Bose glass is analyzed.Comment: 13 pages, 6 figures, extended versio

Studying the Robustness of the Triadic Trust Design with Mechanical Turk Subjects

This paper uses subjects recruited from an online employment exchange to study the robustness of the triadic trust design with a different subject pool. In running our experiments we tried to take advantage of the cost reducing features of the micro-employment culture found on Amazon’s Mechanical Turk. We find that first mover trust is robust to the change in subject pool, but second mover reciprocity was not

Studying the Robustness of the Triadic Trust Design with Mechanical Turk Subjects

This paper uses subjects recruited from an online employment exchange to study the robustness of the triadic trust design with a different subject pool. In running our experiments we tried to take advantage of the cost reducing features of the micro-employment culture found on Amazon’s Mechanical Turk. We find that first mover trust is robust to the change in subject pool, but second mover reciprocity was not

Total ozone changes in the 1987 Antarctic ozone hole

The development of the Antarctic ozone minimum was observed in 1987 with the Nimbus 7 Total Ozone Mapping Spectrometer (TOMS) instrument. In the first half of August the near-polar (60 and 70 deg S) ozone levels were similar to those of recent years. By September, however, the ozone at 70 and 80 deg S was clearly lower than any previous year including 1985, the prior record low year. The levels continued to decrease throughout September until October 5 when a new record low of 109 DU was established at a point near the South Pole. This value is 29 DU less than the lowest observed in 1985 and 48 DU less than the 1986 low. The zonal mean total ozone at 60 deg S remained constant throughout the time of ozone hole formation. The ozone decline was punctuated by local minima formed away from the polar night boundary at about 75 deg S. The first of these, on August 15 to 17, formed just east of the Palmer Peninsula and appears to be a mountain wave. The second major minimum formed on September 5 to 7 again downwind of the Palmer Peninsula. This event was larger in scale than the August minimum and initiated the decline of ozone across the polar region. The 1987 ozone hole was nearly circular and pole centered for its entire life. In previous years the hole was perturbed by intrusions of the circumpolar maximum into the polar regions, thus causing the hole to be elliptical. The 1987 hole also remained in place until the end of November, a few days longer than in 1985, and this persistence resulted in the latest time for recovery to normal values yet observed

On the temporal prognosis, spatial distribution and healing dynamics of damage on young forest plants, caused by voles (Field vole, Microtus agrestis L., bank vole, Clethrionomys glareolus Schreb., and common vole, Microtus arvalis Pallas).

Prognose und Bewertung von Wühlmaus-Nageschäden (Kurzschwanzmäuse: Microtus agrestis, Microtus arvalis, Clethrionomys glareolus; Microtinae, Arvicolidae) am Jungwuchs von Waldbäumen werden erörtert. Auf der Grundlage mehrjähriger Feldversuche wird das Verfahren Index-100-Fangnächte" überprüft und mit einem Köderverfahren zur Kurzschwanzmausprognose verglichen.Das Vermögen verschiedener Waldbaumarten, auf Mäuse-Nageschäden zu reagieren, wurde im Freiland untersucht. Hainbuche (Carpinus betulus) hat trotz herausragender Wundheilung die geringsten Überlebenschancen, Speierling (Sorbus domestica) und Stieleiche (Quercus robur) folgen dichtauf. Buche (Fagus sylvatica) wird zwar sehr stark geschädigt, hat aber hohe Überlebensraten; dasselbe gilt für Vogelkirsche (Prunus avium). Wildapfel (Malus silvestris) und Esche (Fraxinus excelsior) können ohne Überwallung an Ort und Stelle neue Rinde bilden und so Wunden schnellstens wieder verschließen. Kurzschwanzmauspopulationen hängen direkt von der Bodenvegetation ab; diese steht in direktem Zusammenhang mit dem Anteil an der Strahlung, die den Boden erreicht. Das Auftreten von Mäuse-Nageschäden korreliert direkt mit den Strahlungsverhältnissen am Boden. Ein Altholzschirm, sofern er nicht aus den Lichtnadelhölzern Kiefer (Pinus spp.) oder Lärche (Larix spp.) besteht, wirkt sich über die Biotopbeeinflussung auf die Häufigkeit von Mäuse-Nageschäden aus. In Wahlversuchen mit Rötelmäusen konnten für Buchen keine von ihrer Herkunft von Frei- oder Schirmflächen abhängigen Attraktivitätsunterschiede nachgewiesen werden. Parallel zu den Wahlversuchen wurde die Rinde von Buchen beider Provenienzen (Schirm-, Freifläche) auf ihre Inhaltsstoffgehalte hin analysiert. Es konnten Unterschiede in den Nährstoff- und Störstoffgehalten festgestellt werden, diese variierten vor allem innerhalb der Pflanze selbst sehr stark, je nach Entnahmestelle der Rindenprobe. Die für die Verdaulichkeit der Rindennahrung entscheidenden Nährwertindizes, also das Verhältnis zwischen Nährstoffen und Störstoffen, zeigten keine signifikanten Unterschiede. Diese Ergebnisse weisen darauf hin, daß in erster Linie Biotopausprägungsmerkmale dafür verantwortlich sind, ob auf einer Jungwuchsfläche Mäuse-Nageschäden auftreten. Ausgenommen hiervon sind Flächen, die selbst keine nennenswerte Kurzschwanzmauspopulation tragen können, aber von einer solchen invasionsartig besiedelt werden, wenn in deren ursprünglichem Heimatareal grundlegende Veränderungen der Habitatverhältnisse stattfinden.Prognosis and appraisal of damage on young forest trees caused by voles (Microtus agrestis, Microtus arvalis, Clethrionomys glareolus; Microtinae, Arvicolidae) are discussed. On the basis of field-trials, carried out during various years, the assessment method Index-100-Trapnights" is critically reviewed and compared with a method of vole-abundancy-diagnosis using baits. The capability of different tree-species to react on vole-attacks was examined in the field. Despite of their good wound-healing abilities, hornbeam (Carpinus betulus), followed by sorvice-tree (Sorbus domestica) and pendunculate oak (Quercus robur) have low survival rates after a vole-girdling. Beech (Fagus sylvatica), though in general heavily attacked, has a low mortality due to voles, thanks to its excellent capacity of recovery. This is also the case in wild cherry (Prunus avium). Crab apple (Malus silvestris) and ash (Fraxinus excelsior) are able to grow new bark on the spot and thus close inflicted wounds almost immediately. Vole populations directly depend on the ground vegetation; the vegetation stands in close correlation with the amount of radiation reaching the ground. A canopy of old-growth - as long as this is not formed by light-hungry species as pine (Pinus spp.) and larch (Larix spp.)- via the groundvegetation has a strong influence on the appeareance of vole damage. In selection-trials with bank voles no difference in the attractiveness of young beech - trees depending on their provenance from shaded or open areas could be established. Analysing the chemical ingredients of their bark, differences between the two provenances could be found, also differences between the contents of the bark sampled from different parts of the same tree were strong. For the palatability of food its nutritional index that relates nutrients and inhibitants is crucial and these didn't show significant differences between the two origins shade and open. These results indicate that primordially biotop-characteristics are responsible for the occurrence of vole damage in forest young-growth. This is not the case where the carrying capacity of a forest-stand itself would not allow a numerous vole population but habitats in the surroundings that do so suffer drastic changes thus causing their vole-population to migrate to the neighbouring forest stand

Different Evolutionary Modifications as a Guide to Rewire Two-Component Systems

Two-component systems (TCS) are short signalling pathways generally occurring in prokaryotes. They frequently regulate prokaryotic stimulus responses and thus are also of interest for engineering in biotechnology and synthetic biology. The aim of this study is to better understand and describe rewiring of TCS while investigating different evolutionary scenarios. Based on large-scale screens of TCS in different organisms, this study gives detailed data, concrete alignments, and structure analysis on three general modification scenarios, where TCS were rewired for new responses and functions: (i) exchanges in the sequence within single TCS domains, (ii) exchange of whole TCS domains; (iii) addition of new components modulating TCS function. As a result, the replacement of stimulus and promotor cassettes to rewire TCS is well defined exploiting the alignments given here. The diverged TCS examples are non-trivial and the design is challenging. Designed connector proteins may also be useful to modify TCS in selected cases

Do Musicians with Perfect Pitch Have More Autism Traits than Musicians without Perfect Pitch? An Empirical Study

Perfect pitch, also known as absolute pitch (AP), refers to the rare ability to identify or produce a musical tone correctly without the benefit of an external reference. AP is often considered to reflect musical giftedness, but it has also been associated with certain disabilities due to increased prevalence of AP in individuals with sensory and developmental disorders. Here, we determine whether individual autistic traits are present in people with AP. We quantified subclinical levels of autism traits using the Autism-Spectrum Quotient (AQ) in three matched groups of subjects: 16 musicians with AP (APs), 18 musicians without AP (non-APs), and 16 non-musicians. In addition, we measured AP ability by a pitch identification test with sine wave tones and piano tones. We found a significantly higher degree of autism traits in APs than in non-APs and non-musicians, and autism scores were significantly correlated with pitch identification scores (r = .46, p = .003). However, our results showed that APs did not differ from non-APs on diagnostically crucial social and communicative domain scores and their total AQ scores were well below clinical thresholds for autism. Group differences emerged on the imagination and attention switching subscales of the AQ. Thus, whilst these findings do link AP with autism, they also show that AP ability is most strongly associated with personality traits that vary widely within the normal population

Differential roles of polar orbital prefrontal cortex and parietal lobes in logical reasoning with neutral and negative emotional content

© 2018 The Authors To answer the question of how brain pathology affects reasoning about negative emotional content, we administered a disjunctive logical reasoning task involving arguments with neutral content (e.g. Either there are tigers or women in NYC, but not both; There are no tigers in NYC; There are women in NYC) and emotionally laden content (e.g. Either there are pedophiles or politicians in Texas, but not both; There are politicians in Texas; There are no pedophiles in Texas) to 92 neurological patients with focal lesions to various parts of the brain. A Voxel Lesion Symptom Mapping (VLSM) analysis identified 16 patients, all with lesions to the orbital polar prefrontal cortex (BA 10 & 11), as being selectively impaired in the emotional reasoning condition. Another 17 patients, all with lesions to the parietal cortex, were identified as being impaired in the neutral content condition. The reasoning scores of these two patient groups, along with 23 matched normal controls, underwent additional analysis to explore the effect of belief bias. This analysis revealed that the differences identified above were largely driven by trials where there was an incongruency between the believability of the conclusion and the validity of the argument (i.e. valid argument/false conclusion or invalid argument/true conclusion). Patients with lesions to polar orbital prefrontal cortex underperformed in incongruent emotional content trials and over performed in incongruent neutral content trials (compared to both normal controls and patients with parietal lobe lesions). Patients with lesions to parietal lobes underperformed normal controls (at a trend level) in neutral trials where there was a congruency between the believability of the conclusion and the validity of the argument (i.e. valid argument/true conclusion or invalid argument/false conclusion). We conclude that lesions to the polar orbital prefrontal cortex (i) prevent these patients from enjoying any emotionally induced cognitive boost, and (ii) block the belief bias processing route in the neutral condition. Lesions to parietal lobes result in a generalized impairment in logical reasoning with neutral content