Geometric Phase and Modulo Relations for Probability Amplitudes as Functions on Complex Parameter Spaces

We investigate general differential relations connecting the respective behavior s of the phase and modulo of probability amplitudes of the form \amp{\psi_f}{\psi}, where $\ket{\psi_f}$ is a fixed state in Hilbert space and $\ket{\psi}$ is a section of a holomorphic line bundle over some complex parameter space. Amplitude functions on such bundles, while not strictly holomorphic, nevertheless satisfy generalized Cauchy-Riemann conditions involving the U(1) Berry-Simon connection on the parameter space. These conditions entail invertible relations between the gradients of the phase and modulo, therefore allowing for the reconstruction of the phase from the modulo (or vice-versa) and other conditions on the behavior of either polar component of the amplitude. As a special case, we consider amplitude functions valued on the space of pure states, the ray space ${\cal R} = {\mathbb C}P^n$, where transition probabilities have a geometric interpretation in terms of geodesic distances as measured with the Fubini-Study metric. In conjunction with the generalized Cauchy-Riemann conditions, this geodesic interpretation leads to additional relations, in particular a novel connection between the modulus of the amplitude and the phase gradient, somewhat reminiscent of the WKB formula. Finally, a connection with geometric phases is established.Comment: 11 pages, 1 figure, revtex

Incumbent Decisions About Succession Transitions in Family Firms: A Conceptual Model

In the family business literature, succession research has focused on the family member as they enter the leadership role or on the different issues that affect the succession process. Although researchers have acknowledged that succession in family businesses is “punctuated” by decision making events, less attention has been given to understanding how incumbents make decisions about ownership and management transitions. In an effort to continue to understand the succession process it is important to understand how incumbents make decisions about the type of transitions they intend to engage in (i.e., intra-family succession, out of family succession, or no succession). Building on the theory of planned behavior and the socioemotional wealth framework (SEW), this manuscript presents a conceptual framework to understand the factors that influence succession transitions and the role that contextual factors can play in this decision-making process. We present theory driven propositions and discuss the implications for understanding and evaluation of the succession process

An AB effect without closing a loop

We discuss the consequences of the Aharonov-Bohm effect in setups involving several charged particles, wherein none of the charged particles encloses a closed loop around the magnetic flux. We show that in such setups, the AB phase is encoded either in the relative phase of a bi-partite or multi-partite entangled photons states, or alternatively, gives rise to an overall AB phase that can be measured relative to another reference system. These setups involve processes of annihilation or creation of electron/hole pairs. We discuss the relevance of such effects in "vacuum Birefringence" in QED, and comment on their connection to other known effects.Comment: 4 pages, 3 figure

Towards a better understanding of the life cycle of Trypanosoma copemani

Trypanosoma copemani has been found infecting several threatened/endangered marsupial species within Australia and is thought to be a key player in the rapid decline of the woylie (Bettongia penicillata). To better understand the biology and life cycle of this parasite, the growth requirements, and kinetics of infection of two newly described genotypes, T. copemani G1 and G2, were investigated and compared with the T. cruzi strain-10R26 in vitro. Both G1 and G2 were able to infect all four cell lines tested. The number of infected cells where at least one intracellular amastigote of T. copemani G1 and G2 was seen was below 7% and 15% respectively in most cell lines. However, in VERO cells the rate of infection for T. copemani G2 was 70%-approximately seven and two times higher than for G1 and T. cruzi respectively. Despite the higher infection rate, the number of intracellular forms of T. copemani G2 was lower compared with T. cruzi, and intracellular replicating forms were not observed. The capability of T. copemani G2 to infect cells may have important consequences for pathogenicity and suggests it might employ similar strategies to complete its life cycle in the vertebrate host to those seen in T. cruzi

High-throughput analysis of adaptation using barcoded strains of Saccharomyces cerevisiae

Background: Experimental evolution of microbes can be used to empirically address a wide range of questions about evolution and is increasingly employed to study complex phenomena ranging from genetic evolution to evolutionary rescue. Regardless of experimental aims, fitness assays are a central component of this type of research, and low-throughput often limits the scope and complexity of experimental evolution studies. We created an experimental evolution system in Results: We first confirm that barcode insertions do not alter fitness and that barcode sequencing can be used to efficiently detect fitness differences via pooled competition-based fitness assays. Next, we examine the effects of ploidy, chemical stress, and population bottleneck size on the evolutionary dynamics and fitness gains (adaptation) in a total of 76 experimentally evolving, asexual populations by conducting 1,216 fitness assays and analyzing 532 longitudinal-evolutionary samples collected from the evolving populations. In our analysis of these data we describe the strengths of this experimental evolution system and explore sources of error in our measurements of fitness and evolutionary dynamics. Conclusions: Our experimental treatments generated distinct fitness effects and evolutionary dynamics, respectively quantified via multiplexed fitness assays and barcode lineage tracking. These findings demonstrate the utility of this new resource for designing and improving high-throughput studies of experimental evolution. The approach described here provides a framework for future studies employing experimental designs that require high-throughput multiplexed fitness measurements

Influence of MWCNT/surfactant dispersions on the mechanical properties of Portland cement pastes

This work studies the reinforcing effect of Multi Walled Carbon Nanotubes (MWCNT) on cement pastes. A 0.35% solid concentration of MWCNT in powder was dispersed in deionized water with sodium dodecyl sulfate (cationic surfactant), cetylpyridinium chloride (anionic surfactant) and triton X-100 (amphoteric surfactant) using an ultrasonic tip processor. Three concentrations of each surfactant (1mM, 10mM and 100mM) were tested, and all samples were sonicated until an adequate dispersion degree was obtained. Cement pastes with additions of carbon nanotubes of 0.15% by mass of cement were produced in two steps; first the dispersions of MWCNT were combined with the mixing water using an ultrasonic tip processor to guarantee homogeneity, and then cement was added and mixed until a homogeneous paste was obtained. Direct tensile strength, apparent density and open porosity of the pastes were measured after 7 days of curing. It was found that the MWCNT/surfactants dispersions decrease the mechanical properties of the cement based matrix due to an increased porosity caused by the presence of surfactants. © Published under licence by IOP Publishing Ltd

Mode-Wise Entanglement of Gaussian States

We address the decomposition of a multi-mode pure Gaussian state with respect to a bi-partite division of the modes. For any such division the state can always be expressed as a product state involving entangled two-mode squeezed states and single mode local states at each side. The character of entanglement of the state can therefore be understood modewise; that is, a given mode on one side is entangled with only one corresponding mode of the other, and therefore the total bi-partite entanglement is the sum of the modewise entanglement. This decomposition is generally not applicable to all mixed Gaussian states. However, the result can be extended to a special family of "isotropic" states, characterized by a phase space covariance matrix with a completely degenerate symplectic spectrum.Comment: 4 pages, RevTex4. Replaced with revised version with reference added to a previous related paper. Minor typographical errors correcte

Primera evaluación escénica de las playas del Parque Nacional Coiba (Panamá)

Coiba National Park (PNC) is one of the most important marine protected areas in the Americas, as an essential part of the Eastern Tropical Pacific Marine Corridor. As a marine protected area, its main objective is biodiversity conservation, although nature-based tourism and nautical activities are allowed. This research focused on the application of the Coastal Scenery Evaluation System (CSES) method along the entire PNC coastline. Based on two field visits, covering more than 200 km of coastline, 42 beaches were identified and evaluated, the vast majority in highly natural conditions. Similarly, five beaches were analyzed for biological data associated with the diversity of coastal fauna, as a preliminary inventory. The result of the CSES fuzzy logic calculation classified 64% of the beaches in the two highest scenery grades, with only 3 beaches in class IV, and none in class V. Regarding the biological data, macroinvertebrates were mostly represented by 13 mollusks, 1 echinoderm and 1 crustacean. In addition to scientific results, the research identified those beaches with the potential to be certified as coastal scenery of heritage value. In conclusion, this evaluation will help guide nature-based tourism actions within the PNC, and will serve as a baseline for future monitoring of the impact that tourism activity may have on beach fauna and natural attributes.El Parque Nacional Coiba (PNC) es una de las áreas marinas protegidas más importantes de las Américas, como parte esencial del Corredor Marino del Pacífico Oriental Tropical. Como área marina protegida, su principal objetivo es la conservación de la biodiversidad, aunque se permite el eco-turismo y las actividades náuticas. Esta investigación se centró en la aplicación del Sistema de Evaluación de Paisajes Costeros (CSES) a lo largo de todo el litoral de la PNC. A partir de dos visitas de campo, cubriendo más de 200 km de costa, se identificaron y evaluaron 42 playas, la gran mayoría en condiciones altamente naturales. De igual forma, se analizaron cinco playas en busca de datos biológicos asociados a la diversidad de fauna costera, a manera de inventario preliminar. El resultado del cálculo de lógica difusa del CSES clasificó 64% de las playas en los dos grados más altos de paisaje, con solo 3 playas en clase IV y ninguna en clase V. En cuanto a los datos biológicos, los macroinvertebrados estuvieron representados principalmente por 13 moluscos, 1 equinodermo y 1 crustáceo. Además de los resultados científicos, la investigación identificó aquellas playas con potencial para ser certificadas como paisaje costero de valor patrimonial. En conclusión, esta evaluación ayudará a orientar las acciones del eco-turismo dentro de la PNC, y servirá como línea base para futuros controles del impacto que la actividad turística pueda tener sobre la fauna de playa y los atributos naturales

Health care costs of copd in Colombia

Describe the average age of sexual life onset from young people and adolescents, the prevalence of contraceptive methods and explore determinants of pregnancy. A retrospective cohort (2014-2018) was followed by a health insurer of the subsidized regime in Colombia. The study sample consisted of 35,214 young people aged 10-24 years living in 21 municipalities of the Colombian Caribbean region. For the social determinants of pregnancy, a multivariate probit model was estimated using as explanatory variables, housing area, education, family functionality and sexual behavior. 10.3% of women and 14.1% of men had their first sexual encounter before age 14 and 43.5% of women and 37.4% of men began their sex life after age 17. From the young people who claimed to have started their sexual life, 70.9% of the men made use of the condom as a contraceptive method, while the women divided on average 27.2% for the pills and / or injections followed by 16 , 1% in the use of the subdermal implant. As determinants of pregnancy in young people under 20, it was found that variables such as suspending school years [Yes (β = 0.6, p = 0.006)], being planned with hormonal method [Yes (β = 0.5, p = 0.000)] or start sexual life [Between 10 to 14 years (β = 0.14, p = 0.000)], increase the likelihood of young women becoming pregnant at some time in their life. These results also showed that the schooling of the young [University (β = -0.4, p = 0.038)] and always use condoms in sexual intercourse [Yes (β = -0.5, p = 0.042)] help prevent the pregnancy event from occurring. The age of sexual onset establishes a basis on which decision makers should intervene for promote a safe sex life, from use of anticonceptives in young people and thus avoiding unplanned pregnancy

Importancia del mantenimiento industrial dentro de los procesos de producción

El presente artículo hace referencia a la importancia que tiene la planificación del mantenimiento dentro cualquier tipo de empresa que desee alcanzar niveles elevados de calidad. Además muestra una breve reseña histórica de los cambios que ha tenido la implementación de los modelos de mantenimiento en la industria