A new contribution to the nuclear modification factor of non-photonic electrons in Au+Au collisions at sqrt(s) = 200 GeV

We investigate the effect of the so-called anomalous baryon/meson enhancement to the nuclear modification factor of non-photonic electrons in Au+Au collisions at sqrt(s) = 200 GeV. It is demonstrated that an enhancement of the charm baryon/meson ratio, as it is observed for non-strange and strange hadrons, can be responsible for part of the amplitude of the nuclear modification factor of non-photonic electrons. About half of the measured suppression of non-photonic electrons in the 2-4 pt range can be explained by a charm baryon/meson enhancement of 5. This contribution to the non-photonic electron nuclear modification factor has nothing to do with heavy quark energy loss.Comment: 14 pages, 3 figure

Eigenvalue estimates for submanifolds of warped product spaces

We give lower bounds for the fundamental tone of open sets in minimal submanifolds immersed into warped product spaces of type $N^n \times_f Q^q$, where $f \in C^\infty(N)$. We also study the essential spectrum of these minimal submanifolds.Comment: 17 page

Breaking the Rayleigh-Plateau instability limit using thermocavitation within a droplet

We report on the generation of liquid columns that extend far beyond the traditional Rayleigh-Plateau instability onset. The columns are driven by the acoustic pressure wave emitted after bubble collapse. A high-speed video imaging device, which records images at a rate of up to 105 fps, was employed to follow their dynamics. These bubbles, commonly termed thermocavitation bubbles, are generated by focusing a midpower (275 mW) continuous wavelength laser into a highly absorbing liquid droplet. A simple model of the propagation of the pressure wavefront emitted after the bubble collapse shows that focusing the pressure wave at the liquid-air interface drives the evolution of the liquid columns. Control over the aspect ratio of the liquid column is realized by adjusting the cavitation bubble's size, beam focus position, and droplet volume. © 2013 by Begell House, Inc

The Effect of Age and Sex on Lower Extremity Joint Power Coordination

Previous research has provided conflicting results regarding interjoint coordination during a squat jump for young and old adults. In particular, researchers have noted if a proximal-to-distal sequencing (PDS) pattern characterized by hip, then knee, then ankle movement was utilized. Argaud et al. (2019) concluded that both groups used a PDS pattern while Haguenauer et al. (2005) reported that older adults exhibited a more simultaneous strategy. However, both of these studies only investigated male subjects. PURPOSE: The purpose of this study was to determine if there are differences in joint power sequencing between males and females and between young and older adults during a squat jump. METHODS: 32 moderately active and injury-free subjects participated (19 young (9F, 10M) and 13 older (7F, 6M)). There was no significant difference in the Physical Activity Rating form levels between age groups or sexes. Subjects performed squat jumps from a starting position with a minimum knee flexion angle of 120 degrees with hands on hips and rest given between trials. Three-dimensional body coordinates and ground reaction force data were collected using seven Vicon Vantage cameras (120 Hz) and two Kistler force plates (1200 Hz), respectively. Three trials per subject were used for analysis, excluding any trials with a countermovement. Hip, knee and ankle joint power data were computed using Nexus software and used to assign the degree of PDS for each trial (both leg, one leg, neither leg). Chi-squared was run to determine associations between sex and age with degree of PDS (p \u3c 0.05). RESULTS: There was a statistically significant association between age and degree of PDS (p = 0.041). Both legs used PDS for 74% and 49% of the younger and older adult trials, respectively, and neither leg used PDS for 12% and 21% of their trials, respectively. There was no significant association between sex and degree of PDS. However, 71% and 56% of the males and female trials used PDS for both legs while 8% and 23% of their trials used PDS for neither leg. CONCLUSION: It appears that older adults, especially females, use a PDS strategy less frequently when attempting to generate lower extremity power. This difference is not related to activity levels or disease and may be related to neuromuscular changes associated with aging or jump experience. This research was funded by the Swenson Summer Research Fellowship Program

Environmental knowledge management: A long-term enabler of tourism development

A review of the literature confirms that there is a need for knowledge management frameworks which support knowledge creation, particularly in those organisations having to operate in a changing environment. Socialisation, externalisation, combination and internalisation continue to be key processes for the creation of knowledge which enables organisations to successfully address environmental challenges. This paper examines the relevance and importance of a SECI model as an enabler of the processes of reusing and updating the environmental knowledge of an organisation. The research reported has confirmed that time is a key component of the implementation of a SECI model in organisations operating in a changing environment. Thins been confirmed that such a strategy should focus on the reuse of prior environmental knowledge as a mechanism to establish within the organisation a context where new knowledge management processes are understood and adopted by employees. The paper also examines the relationship between environmental knowledge and organisational performance indicators. These relationships are examined through an empirical study of 87 companies in the Spanish hospitality sector. The results of the study indicate that environmental knowledge at any given time (T) is significant in predicting the knowledge management processes that may be successfully implemented at a later point in time (T + 6 years). (C) 2015 Elsevier Ltd. All rights reserved

Blurred Lines Between Competition and Parasitism

Accurately describing the ecological relationships between species is more than mere semantics-doing so has profound practical and applied implications, not the least of which is that inaccurate descriptions can lead to fundamentally incorrect predicted outcomes of community composition and functioning. Accurate ecological classifications are particularly important in the context of global change, where species interactions can change rapidly following shifts in species composition. Here, we argue that many common ecological interactions-particularly competition and parasitism-can be easily confused and that we often lack empirical evidence for the full reciprocal interaction among species. To make our case and to propose a theoretical framework for addressing this problem, we use the interactions between lianas and trees, whose outcomes have myriad implications for the ecology and conservation of tropical forests (e.g., Schnitzer et al. 2015)

Prevención cardiovascular y de la osteoporosis con terapia hormonal sustitutiva

Se recomienda actualmente que todo médico -sea cual sea su especialidad- aproveche la oportunidad que supone la atención clínica a cualquier mujer postmenopáusica o que se halle en torno a la menopausia para aconsejarle acerca de los beneficios y riesgos que supone la terapia hormonal sustitutiva (THS) con estrógenos y progesterona. Una vez que sea adecuadamente informada de estos beneficios y riesgos, debe ser la propia mujer quien decida si va a iniciar o no esta terapia, teniendo en cuenta no sólo su propio perfil de riesgo sino también sus preferencias. Los beneficios más claros se refieren a la reducción del riesgo de osteoporosis y de fracturas, así como al control y prevención de algunos síntomas frecuentes en la menopausia. Para prevenir la osteoporosis se requiere un uso continuado de IaTHS. También existen cada vez más argumentos que sugieren una reducción del riesgo de un primer episodio coronario. No obstante, no hay pruebas de que laTHS sea útil en la prevención secundaria de la cardiopatía isquémica o aporte alguna protección frente a los accidentes cerebrovasculares. Las desventajas más importantes de la THS se refieren a un mayor riesgo de hiperplasia de endometrio y de cáncer endometrial cuando se usan estrógenos solos, sin combinarlos con progestágenos. También existe un pequeño incremento del riesgo de cáncer de mama cuando se prolonga la THS, también cuando se asocian progestágenos

Controllable direction of liquid jets generated by thermocavitation within a droplet.

A high-velocity fluid stream ejected from an orifice or nozzle is a common mechanism to produce liquid jets in inkjet printers or to produce sprays among other applications. In the present research, we show the generation of liquid jets of controllable direction produced within a sessile water droplet by thermocavitation. The jets are driven by an acoustic shock wave emitted by the collapse of a hemispherical vapor bubble at the liquid-solid/substrate interface. The generated shock wave is reflected at the liquid-air interface due to acoustic impedance mismatch generating multiple reflections inside the droplet. During each reflection, a force is exerted on the interface driving the jets. Depending on the position of the generation of the bubble within the droplet, the mechanical energy of the shock wave is focused on different regions at the liquid-air interface, ejecting cylindrical liquid jets at different angles. The ejected jet angle dependence is explained by a simple ray tracing model of the propagation of the acoustic shock wave inside the droplet