Temporal and spatial evolution of a waxing then waning catastrophic density current revealed by chemical mapping

We reconstruct the behavior of a catastrophic sustained radial pyroclastic density current as it waxed then waned during its brief lifespan. By subdividing the deposit into 8 time slices using a chemical tracer, we show that the sustained current initially was topographically restricted, but that its leading edge advanced in all directions, encroaching upon and gradually ascending hills. During peak flow the current reached its maximum extent and overtopped all topographic highs. After this, and while the current direction from source was maintained, the leading edge gradually retreated sourceward. High-resolution analysis of the depositional architecture reveals how the flow dynamics evolved and runout distance of the sustained density current rapidly increased then decreased, reflecting the dominant influence of changing mass flux, as demonstrated in numerical models but not previously distinguished in a natural deposit

Non-universality of dark-matter halos: cusps, cores, and the central potential

Dark-matter halos grown in cosmological simulations appear to have central NFW-like density cusps with mean values of $d\log\rho/d\log r \approx -1$, and some dispersion, which is generally parametrized by the varying index $\alpha$ in the Einasto density profile fitting function. Non-universality in profile shapes is also seen in observed galaxy clusters and possibly dwarf galaxies. Here we show that non-universality, at any given mass scale, is an intrinsic property of DARKexp, a theoretically derived model for collisionless self-gravitating systems. We demonstrate that DARKexp - which has only one shape parameter, $\phi_0$ - fits the dispersion in profile shapes of massive simulated halos as well as observed clusters very well. DARKexp also allows for cored dark-matter profiles, such as those found for dwarf spheroidal galaxies. We provide approximate analytical relations between DARKexp $\phi_0$, Einasto $\alpha$, or the central logarithmic slope in the Dehnen-Tremaine analytical $\gamma$-models. The range in halo parameters reflects a substantial variation in the binding energies per unit mass of dark-matter halos.Comment: ApJ, in press, 10 pages, 7 figure

Annotated list of the scale insects of Guatemala

Ένας λεπτομερής κατάλογος των ειδών της οικογένειας Coccidae παρουσιάζεται για μια χώρα της κεντρικής Αμερικής, τη Γουατεμάλα. Το φυτό ξενιστής και η τοποθεσία παρουσιάζεται για κάθε είδος μαζί με παρατηρήσεις για την ταξινομική του κατάσταση. Ο κατάλογος αναπτύχθηκε από μελέτες που πραγματοποίησε ο συγγραφέας στη Γουατεμάλα καθώς και από υλικό που συλλέχθηκε από άλλους επιστήμονες την περίοδο 1990-2007, καθώς επίσης και από την ανασκόπηση της βιβλιογραφίας και καταγραφές που βρίσκονται στις ΗΠΑ, στη συλλογή του Εθνικού Μουσείου Κοκκοειδών. Η μελέτη του παραπάνω υλικού οδήγησε στην αύξηση του αριθμού των ειδών της οικογένειας Coccidae από την Γουατεμάλα σε 29 είδη που ανήκουν σε 23 γένη. Η Γουατεμάλα πλέον κατατάσσεται ως δεύτερη σε αριθμό ειδών της οικογένειας Coccidae μεταξύ των χωρών της κεντρικής Αμερικής, μετά από τον Παναμά όπου έχουν καταγραφεί 36 είδη που ανήκουν σε 18 γένη.An annotated checklist of the soft scale insects (Hemiptera: Coccidae) is given for the Central American country of Guatemala. Host and locality data is presented for each species, along with notes on its taxonomic status. The list was developed from study of materials collected in Guatemala by the author and others during the years 1990-2007, and from a review of the literature and records and slide material in the United States National Museum Coccoidea Collection. A study of these materials has increased the number of soft scale insects currently known from Guatemala to 29 species belonging to 23 genera. Guatemala currently ranks second in the number of soft scale insects known from Central American countries below Panama, which has 36 recorded species belonging to 18 genera

Sin city Kentucky : Newport, Kentucky\u27s vice heritage and its legal extinction, 1920-1991.

This thesis is an examination and analysis of the role of law enforcement in the transformation of a city\u27s downtown from one dominated by sleazy strip bars and prostitutes to one of family entertainment. The focus is on the police and prosecutors; however, a substantial portion of the thesis discusses the role of Newport, Kentucky\u27s, City Commission. The thesis chronicles Newport\u27s vice history from early Prohibition through the early 1990s and the impact of city government upon anti-vice efforts becomes evident, but law enforcement that paved the way. The approach is chronological. Newport\u27s transformation was an evolutionary process. Elected officials influenced the city\u27s vice problems, but state legislative changes and United States Supreme Court cases also had a part in the course of anti-vice efforts. Changes in the law and court cases often gave city officials and law enforcement direction in the regulation and prosecution of illegal vices

Capital and Punishment: Resource Scarcity Increases Endorsement of the Death Penalty

Faced with punishing severe offenders, why do some prefer imprisonment whereas others impose death? Previous research exploring death penalty attitudes has primarily focused on individual and cultural factors. Adopting a functional perspective, we propose that environmental features may also shape our punishment strategies. Individuals are attuned to the availability of resources within their environments. Due to heightened concerns with the costliness of repeated offending, we hypothesize that individuals tend toward elimination-focused punishments during times of perceived scarcity. Using global and United States data sets (studies 1 and 2), we find that indicators of resource scarcity predict the presence of capital punishment. In two experiments (studies 3 and 4), we find that activating concerns about scarcity causes people to increase their endorsement for capital punishment, and this effect is statistically mediated by a reduced willingness to risk repeated offenses. Perceived resource scarcity shapes our punishment preferences, with important policy implications

Unfair competition governs the interaction of pCPI-17 with myosin phosphatase (PP1-MYPT1).

The small phosphoprotein pCPI-17 inhibits myosin light-chain phosphatase (MLCP). Current models postulate that during muscle relaxation, phosphatases other than MLCP dephosphorylate and inactivate pCPI-17 to restore MLCP activity. We show here that such hypotheses are insufficient to account for the observed rapidity of pCPI-17 inactivation in mammalian smooth muscles. Instead, MLCP itself is the critical enzyme for pCPI-17 dephosphorylation. We call the mutual sequestration mechanism through which pCPI-17 and MLCP interact inhibition by unfair competition: MLCP protects pCPI-17 from other phosphatases, while pCPI-17 blocks other substrates from MLCP\u27s active site. MLCP dephosphorylates pCPI-17 at a slow rate that is, nonetheless, both sufficient and necessary to explain the speed of pCPI-17 dephosphorylation and the consequent MLCP activation during muscle relaxation

Experimental Design for the LATOR Mission

This paper discusses experimental design for the Laser Astrometric Test Of Relativity (LATOR) mission. LATOR is designed to reach unprecedented accuracy of 1 part in 10^8 in measuring the curvature of the solar gravitational field as given by the value of the key Eddington post-Newtonian parameter \gamma. This mission will demonstrate the accuracy needed to measure effects of the next post-Newtonian order (~G^2) of light deflection resulting from gravity's intrinsic non-linearity. LATOR will provide the first precise measurement of the solar quadrupole moment parameter, J2, and will improve determination of a variety of relativistic effects including Lense-Thirring precession. The mission will benefit from the recent progress in the optical communication technologies -- the immediate and natural step above the standard radio-metric techniques. The key element of LATOR is a geometric redundancy provided by the laser ranging and long-baseline optical interferometry. We discuss the mission and optical designs, as well as the expected performance of this proposed mission. LATOR will lead to very robust advances in the tests of Fundamental physics: this mission could discover a violation or extension of general relativity, or reveal the presence of an additional long range interaction in the physical law. There are no analogs to the LATOR experiment; it is unique and is a natural culmination of solar system gravity experiments.Comment: 16 pages, 17 figures, invited talk given at ``The 2004 NASA/JPL Workshop on Physics for Planetary Exploration.'' April 20-22, 2004, Solvang, C

Remote capacitive sensing in two-dimension quantum-dot arrays

We investigate gate-defined quantum dots in silicon on insulator nanowire field-effect transistors fabricated using a foundry-compatible fully-depleted silicon-on-insulator (FD-SOI) process. A series of split gates wrapped over the silicon nanowire naturally produces a $2\times n$ bilinear array of quantum dots along a single nanowire. We begin by studying the capacitive coupling of quantum dots within such a 2$\times$2 array, and then show how such couplings can be extended across two parallel silicon nanowires coupled together by shared, electrically isolated, 'floating' electrodes. With one quantum dot operating as a single-electron-box sensor, the floating gate serves to enhance the charge sensitivity range, enabling it to detect charge state transitions in a separate silicon nanowire. By comparing measurements from multiple devices we illustrate the impact of the floating gate by quantifying both the charge sensitivity decay as a function of dot-sensor separation and configuration within the dual-nanowire structure.Comment: 9 pages, 3 figures, 35 cites and supplementar