Exotic looped trajectories via quantum marking

We provide an analytical and theoretical study of exotic looped trajectories (ELTs) in a double-slit interferometer with quantum marking. We use an excited Rydberg-like atom and which-way detectors such as superconducting cavities, just as in the Scully-Englert-Walther interferometer. We indicate appropriate conditions on the atomic beam or superconducting cavities so that we determine an interference pattern and fringe visibility exclusive from the ELTs. We quantitatively describe our results for Rubidium atoms and propose this framework as an alternative scheme to the double-slit experiment modified to interfere only these exotic trajectories.Comment: 10 pages, 5 figure

Dirac-Hestenes spinor fields in Riemann-Cartan spacetime

In this paper we study Dirac-Hestenes spinor fields (DHSF) on a four-dimensional Riemann-Cartan spacetime (RCST). We prove that these fields must be defined as certain equivalence classes of even sections of the Clifford bundle (over the RCST), thereby being certain particular sections of a new bundle named Spin-Clifford bundle (SCB). The conditions for the existence of the SCB are studied and are shown to be equivalent to the famous Geroch's theorem concerning to the existence of spinor structures in a Lorentzian spacetime. We introduce also the covariant and algebraic Dirac spinor fields and compare these with DHSF, showing that all the three kinds of spinor fields contain the same mathematical and physical information. We clarify also the notion of (Crumeyrolle's) amorphous spinors (Dirac-K\"ahler spinor fields are of this type), showing that they cannot be used to describe fermionic fields. We develop a rigorous theory for the covariant derivatives of Clifford fields (sections of the Clifford bundle (CB)) and of Dirac-Hestenes spinor fields. We show how to generalize the original Dirac-Hestenes equation in Minkowski spacetime for the case of a RCST. Our results are obtained from a variational principle formulated through the multiform derivative approach to Lagrangian field theory in the Clifford bundle.Comment: 45 pages, special macros kapproc.sty and makro822.te

Characterization, Classification And Analysis Of The Main Properties Of The Southwestern Goias Soil

Characterization of the soil and the grouping of its properties through main component analysis can assist in the classification and observation of the consequences of the conversion of native forest areas in pastures. Such data can aid in management practices. Considering the lack of studies in Cerrado soils of south-western Goias, developed metagranites of Jurubatuba suite, the objective was to classify and study the physical, chemical and mineralogical soil (under native forest and pasture) Southwest of Goias. Soil sampling and classification followed the Field Methods Manual and the Brazilian System of Soil Classification, respectively. The physical, chemical and mineralogical soil were studied, as well as main component analysis made for these attributes. The profile 1 under native forest was classified as "Cambissolo Háplico Tb eutrófico latossólico". The profile 2 under degraded pasture was rated "Latossolo Amarelo eutrófico típico". In addition, the profile 3 under rotated pasture was rated as "Latossolo Vermelho eutrófico chernossólico". It was observed that the "Latossolos" have higher bulk density and soil penetration resistance, indicating greater soil compaction. They showed high amounts of iron oxides and minor amount of nutrients such as calcium and magnesium. The principal component analysis allowed the grouping of profiles into two groups. Group 1 brought together the properties related to "Latossolos", and the second was related to "Cambissolo" properties. Thus, the principal components analysis aids the understanding of soil properties and the grouping of soils with similar characteristics, the level of order and management.3731135115

EVALUATION OF ACCIDENTS WITH DOMINO EFFECT IN LPG STORAGE AREAS

The term domino effect denotes a chain of accidents, or situations, in which a fire/explosion load generated by an accident in one unit in an industry causes secondary and higher order accidents in other units. Such chains of accidents have a greater propensity to cause damage than stand-alone accidents. Most of the past risk assessment studies deal with accident in a single industry, more so in one of the units of an industry. But, often, accident in one unit causes a secondary accident in a nearby unit, which in turn may trigger a tertiary accident, and so on. The probability of occurrence and adverse impacts of such domino or cascading effects are increasing due to increasing congestion in industrial complexes and increasing density of human population around such complexes. Accidents with domino effect are seldom studied. LPG storage areas could produce the worst possible consequences in the event of an unforeseen incident. This work illustrates the application of models to evaluate the impacts of events with fire and explosion in LPG tanks on other similar units in the park and the possibility of occurrence of a domino effect. The criteria for occurrence of accidents with domino effect adopted in this work were 37.5 kW/m2 in case of fire radiation and an overpressure of 0.7 atm in explosion cases in a receptor body. The spacing between LPG tanks was evaluated. The results show that such spacing is minimal and does not represent, as it should, a parameter indicating a safe distance able to prevent the propagation of an accident with domino effect

Spectral, mineralogical, and geochemical variations across Home Plate, Gusev Crater, Mars indicate high and low temperature alteration

Over the last ~ 3 years in Gusev Crater, Mars, the Spirit rover observed coherent variations in color, mineralogy, and geochemistry across Home Plate, an ~ 80 m-diameter outcrop of basaltic tephra. Observations of Home Plate from orbit and from the summit of Husband Hill reveal clear differences in visible/near-infrared (VNIR) colors between its eastern and western regions that are consistent with mineralogical compositions indicated by Mössbauer spectrometer (MB) and by Miniature Thermal Emission Spectrometer (Mini-TES). Pyroxene and magnetite dominate the east side, while olivine, nanophase Fe oxide (npOx) and glass are more abundant on the western side. Alpha Particle X-Ray Spectrometer (APXS) observations reveal that eastern Home Plate has higher Si/Mg, Al, Zn, Ni, and K, while Cl and Br are higher in the west. We propose that these variations are the result of two distinct alteration regimes that may or may not be temporally related: a localized, higher temperature recrystallization and alteration of the east side of Home Plate and lower temperature alteration of the western side that produced npOx

Reliability and Test-Retest Agreement of Mechanical Variables Obtained During Countermovement Jump

International Journal of Exercise Science 13(4): 6-17, 2020. The countermovement jump (CMJ) is often used as performance measure and monitoring tool. Traditionally, jump height (JH) is most often studied and reported, but other variables (e.g. force, velocity, power) can also be obtained during CMJ testing on a force plate. The aim of this study was to determine the intra-rater reliability of mechanical variables obtained during CMJs. For this, 41 physically active men (24 ± 4 years) performed four CMJs on a force plate with an interval of 48 to 168 hours (test-retest design). Six variables were analyzed: 1) jump height (JH), 2) peak force (PF), 3) peak power (PP), 4) velocity at takeoff (VTO), 5) rate of force (RFD) and 6) power (RPD) development. Five variables showed to be reliable (i.e. CV \u3c 10%), except RFD (CV of 12.9%). Although JH exhibited an acceptable level of reliability (r= 0.94 and CV = 5.8%), better scores were observed for PF, VTO, and PP (CV ranging from 2.5 to 5.1%). The PF showed the best reliability scores (r= 0.99 and CV = 2.5%) and RPD, a relatively unexamined variable compared to the others, showed an acceptable level of reliability (r= 0.96 and CV = 7.8%). Therefore, JH, PF, PP, VTO, and RPD demonstrated acceptable scores of reliability. PF seems to be the most appropriate variable to use when small changes in performance are expected. Future studies should investigate the importance of RPD for performance evaluation

A computerized fuzzy logic system for evaluation of the cardiovascular autonomic function based on multiple functional tests

Abstract The interest in the study o