A Logical Product Approach to Zonotope Intersection

We define and study a new abstract domain which is a fine-grained combination of zonotopes with polyhedric domains such as the interval, octagon, linear templates or polyhedron domain. While abstract transfer functions are still rather inexpensive and accurate even for interpreting non-linear computations, we are able to also interpret tests (i.e. intersections) efficiently. This fixes a known drawback of zonotopic methods, as used for reachability analysis for hybrid sys- tems as well as for invariant generation in abstract interpretation: intersection of zonotopes are not always zonotopes, and there is not even a best zonotopic over-approximation of the intersection. We describe some examples and an im- plementation of our method in the APRON library, and discuss some further in- teresting combinations of zonotopes with non-linear or non-convex domains such as quadratic templates and maxplus polyhedra

Impacts de restrictions en eau d'irrigation sur les exploitations et les filières agricoles en Beauce

Beaucoup d’agriculteurs, comme les opérateurs des filières aval qui collectent ou transforment leur production, dépendent de l'irrigation. Or, dans de nombreuses régions du monde, structurellement ou conjoncturellement, les ressources en eau disponibles déclinent et sont soumises à des contingentements de plus en plus sévères. Cette étude vise à analyser les conséquences de scénarios de fortes baisses de la disponibilité en eau sur les stratégies des agriculteurs en termes de choix d’assolement et de mode de conduite et d’irrigation des cultures ainsi que l’effet de ces stratégies sur l’organisation de filières locales. Elle a été mise en oeuvre en France, dans la plaine de la Beauce, où une forte proportion de l'agriculture est irriguée à partir d'une ressource souterraine soumise à un dispositif de gestion volumétrique. L’évaluation des impacts de restrictions d’eau s’appuie sur une analyse économique des filières locales ainsi que sur des ateliers participatifs regroupant des agriculteurs et des opérateurs des unités aval. Les résultats montrent les effets de restrictions d’eau sur les choix d’assolement des agriculteurs, les volumes de production à l’échelle du territoire, les marges brutes des exploitations et les valeurs ajoutées des filières. / Many farmers, and the large set of downstream operators who depend on their farm products, have become depend-ent on irrigation. But, in many parts of the world, water resources are declining for structural or temporary reasons. Farmers have to reduce water consumption by growing crops with lower water requirement and apply optimal irri-gation strategies. The strategies they choose can have major consequences for downstream operators and local agro-industries. This paper analyzes the impacts and consequences of high water restrictions scenarios for farmers and the subsectors depending on their production. This approach was imple-mented in France, in the region of Beauce, where irrigation relies on groundwater use and on a volumetric management of the local aquifer. Scenarios based on two different levels of water availability reduction were assessed and strategies to face reduced water availability were analyzed for both farmers and downstream operators. The analysis was based on a technical diagnosis of the local organization, an eco-nomic analysis of value added, and participatory workshops including farmers, downstream operators and state repre-sentatives. Our analyses showed how farmers would adapt to water restriction and, depending on their choice of pro-duction, how their strategies could impact the volume of production at sub-regional level, the value added at subsec-tor level and could lead to competition between down-stream operators

CTX: A Clock-Gating-Based Test Relaxation and X-Filling Scheme for Reducing Yield Loss Risk in At-Speed Scan Testing

At-speed scan testing is susceptible to yield loss risk due to power supply noise caused by excessive launch switching activity. This paper proposes a novel two-stage scheme, namely CTX (Clock-Gating-Based Test Relaxation and X-Filling), for reducing switching activity when test stimulus is launched. Test relaxation and X-filling are conducted (1) to make as many FFs inactive as possible by disabling corresponding clock-control signals of clock-gating circuitry in Stage-1 (Clock-Disabling), and (2) to make as many remaining active FFs as possible to have equal input and output values in Stage-2 (FF-Silencing). CTX effectively reduces launch switching activity, thus yield loss risk, even with a small number of donpsilat care (X) bits as in test compression, without any impact on test data volume, fault coverage, performance, and circuit design.2008 17th Asian Test Symposium (ATS 2008), 24-27 November 2008, Sapporo, Japa

Bound States and Critical Behavior of the Yukawa Potential

We investigate the bound states of the Yukawa potential $V(r)=-\lambda \exp(-\alpha r)/ r$, using different algorithms: solving the Schr\"odinger equation numerically and our Monte Carlo Hamiltonian approach. There is a critical $\alpha=\alpha_C$, above which no bound state exists. We study the relation between $\alpha_C$ and $\lambda$ for various angular momentum quantum number $l$, and find in atomic units, $\alpha_{C}(l)= \lambda [A_{1} \exp(-l/ B_{1})+ A_{2} \exp(-l/ B_{2})]$, with $A_1=1.020(18)$, $B_1=0.443(14)$, $A_2=0.170(17)$, and $B_2=2.490(180)$.Comment: 15 pages, 12 figures, 5 tables. Version to appear in Sciences in China

Effective Launch-to-Capture Power Reduction for LOS Scheme with Adjacent-Probability-Based X-Filling

It has become necessary to reduce power during LSI testing. Particularly, during at-speed testing, excessive power consumed during the Launch-To-Capture (LTC) cycle causes serious issues that may lead to the overkill of defect-free logic ICs. Many successful test generation approaches to reduce IR-drop and/or power supply noise during LTC for the launch-off capture (LOC) scheme have previously been proposed, and several of X-filling techniques have proven especially effective. With X-filling in the launch-off shift (LOS) scheme, however, adjacent-fill (which was originally proposed for shift-in power reduction) is used frequently. In this work, we propose a novel X-filling technique for the LOS scheme, called Adjacent-Probability-based X-Filling (AP-fill), which can reduce more LTC power than adjacent-fill. We incorporate AP-fill into a post-ATPG test modification flow consisting of test relaxation and X-filling in order to avoid the fault coverage loss and the test vector count inflation. Experimental results for larger ITC\u2799 circuits show that the proposed AP-fill technique can achieve a higher power reduction ratio than 0-fill, 1-fill, and adjacent-fill.2011 Asian Test Symposium, 20-23 November 2011, New Delhi, Indi

Multiple Scale Reorganization of Electrostatic Complexes of PolyStyrene Sulfonate and Lysozyme

We report on a SANS investigation into the potential for these structural reorganization of complexes composed of lysozyme and small PSS chains of opposite charge if the physicochemical conditions of the solutions are changed after their formation. Mixtures of solutions of lysozyme and PSS with high matter content and with an introduced charge ratio [-]/[+]intro close to the electrostatic stoichiometry, lead to suspensions that are macroscopically stable. They are composed at local scale of dense globular primary complexes of radius ~ 100 {\AA}; at a higher scale they are organized fractally with a dimension 2.1. We first show that the dilution of the solution of complexes, all other physicochemical parameters remaining constant, induces a macroscopic destabilization of the solutions but does not modify the structure of the complexes at submicronic scales. This suggests that the colloidal stability of the complexes can be explained by the interlocking of the fractal aggregates in a network at high concentration: dilution does not break the local aggregate structure but it does destroy the network. We show, secondly, that the addition of salt does not change the almost frozen inner structure of the cores of the primary complexes, although it does encourage growth of the complexes; these coalesce into larger complexes as salt has partially screened the electrostatic repulsions between two primary complexes. These larger primary complexes remain aggregated with a fractal dimension of 2.1. Thirdly, we show that the addition of PSS chains up to [-]/[+]intro ~ 20, after the formation of the primary complex with a [-]/[+]intro close to 1, only slightly changes the inner structure of the primary complexes. Moreover, in contrast to the synthesis achieved in the one-step mixing procedure where the proteins are unfolded for a range of [-]/[+]intro, the native conformation of the proteins is preserved inside the frozen core

The heterosexual human immunodeficiency virus type 1 epidemic in Thailand is caused by an intersubtype (A/E) recombinant of African origin

Since 1989, human immunodeficiency virus type 1 (HIV-1) has spread explosively through the heterosexual population in Thailand. This epidemic is caused primarily by viruses classified as "subtype E", which, on the basis of limited sequence comparisons, appear to represent hybrids of subtypes A (gag) and E (env). However, the true evolutionary origins of "subtype E" viruses are still obscure since no complete genomes have been analyzed, and only one full-length subtype A sequence has been available for phylogenetic comparison. In this study, we determined full-length proviral sequences for "subtype E" viruses from Thailand (93TH253) and the Central African Republic (90CR402) and for a subtype A virus from Uganda (92UG037). We also sequenced the long terminal repeat (LTR) regions from 16 virus strains representing clades A, C, E, F, and G. Detailed phylogenetic analyses of these sequences indicated that "subtype E" viruses do indeed represent A/E recombinants with multiple points of crossover along their genomes. The extracellular portion of env, parts of vif and vpr, as well as most of the LTR are of subtype E origin, whereas the remainder of the genome is of subtype A origin. The possibility that the discordant phylogenetic positions of "subtype E" viruses in gag- and env-derived trees are the result of unusual rates or patterns of evolution was also considered but was ruled out on the basis of two lines of evidence: (i) phylogenetic trees constructed for synonymous and nonsynonymous substitutions yielded the same discordant branching orders for "subtype E" gag and env gene sequences, thus excluding selection-driven evolution, and (ii) multiple crossovers in the viral genome are most consistent with the copy choice model of recombination and have been observed in other documented examples of HIV-1 intersubtype recombination. Thai and CAR "subtype E" viruses exhibited the same pattern of A/E mosaicism, indicating that the recombination event occurred in Africa prior to the spread of virus to Asia. Finally, all "subtype E" viruses were found to contain a distinctive two-nucleotide bulge in their transactivation response (TAR) elements. This feature was present only in viruses which also contained a subtype A 5' pol region (i.e., subtype A viruses or A/D and A/E recombinants), raising the possibility of a functional linkage between the TAR region and the polymerase. The implications of epidemic spread of a recombinant HIV-1 strain to viral natural history and vaccine development are discussed

NeuroD1 regulation of migration accompanies the differential sensitivity of neuroendocrine carcinomas to TrkB inhibition

The developmental transcription factor NeuroD1 is anomalously expressed in a subset of aggressive neuroendocrine tumors. Previously, we demonstrated that TrkB and neural cell adhesion molecule (NCAM) are downstream targets of NeuroD1 that contribute to the actions of neurogenic differentiation 1 (NeuroD1) in neuroendocrine lung. We found that several malignant melanoma and prostate cell lines express NeuroD1 and TrkB. Inhibition of TrkB activity decreased invasion in several neuroendocrine pigmented melanoma but not in prostate cell lines. We also found that loss of the tumor suppressor p53 increased NeuroD1 expression in normal human bronchial epithelial cells and cancer cells with neuroendocrine features. Although we found that a major mechanism of action of NeuroD1 is by the regulation of TrkB, effective targeting of TrkB to inhibit invasion may depend on the cell of origin. These findings suggest that NeuroD1 is a lineage-dependent oncogene acting through its downstream target, TrkB, across multiple cancer types, which may provide new insights into the pathogenesis of neuroendocrine cancers

NMR implementation of Factoring Large Numbers with Gau\ss{}Sums: Suppression of Ghost Factors

Finding the factors of an integer can be achieved by various experimental techniques, based on an algorithm developed by Schleich et al., which uses specific properties of Gau\ss{}sums. Experimental limitations usually require truncation of these series, but if the truncation parameter is too small, it is no longer possible to distinguish between factors and so-called "ghost" factors. Here, we discuss two techniques for distinguishing between true factors and ghost factors while keeping the number of terms in the sum constant or only slowly increasing. We experimentally test these modified algorithms in a nuclear spin system, using NMR.Comment: 4 pages, 5 figure

The Distance To The Hyades Cluster Based On Hubble Space Telescope Fine Guidance Sensor Parallaxes

Trigonometric parallax observations made with the Hubble Space Telescope (HST) Fine Guidance Sensor (FGS) 3 of seven Hyades members in six fields of view have been analyzed along with their proper motions to determine the distance to the cluster. Knowledge of the convergent point and mean proper motion of the Hyades is critical to the derivation of the distance to the center of the cluster. Depending on the choice of the proper-motion system, the derived cluster center distance varies by 9%. Adopting a reference distance of 46.1 pc or m - M = 3.32, which is derived from the ground-based parallaxes in the General Catalogue of Trigonometric Stellar Parallaxes (1995 edition), the FK5/PPM proper-motion system yields a distance 4% larger, while the Hanson system yields a distance 2% smaller. The HST FGS parallaxes reported here yield either a 14% or 5% larger distance, depending on the choice of the proper-motion system. Orbital parallaxes (Torres et al.) yield an average distance 4% larger than the reference distance. The variation in the distance derived from the HST data illustrates the importance of the proper-motion system and the individual proper motions to the derivation of the distance to the Hyades center; therefore, a full utilization of the HST FGS parallaxes awaits the establishment of an accurate and consistent proper-motion system.NASA HST GTO, HF-1042.01-93A, HF-1046.01-93A, NAS526555Astronom