2,231 research outputs found
A controlled rate freeze/thaw system for cryopreservation of biological materials
A system which allows programmable temperature-time control for a 5 cc sample volume of an arbitrary biological material was constructed. Steady state and dynamic temperature control was obtained by supplying heat to the sample volume through resistive elements constructed as an integral part of the sample container. For cooling purposes, this container was totally immersed into a cold heat sink. Sample volume thermodynamic property data were obtained by measurements of heater power and heat flux through the container walls. Using a mixture of dry ice and alcohol at -79 C, sample volume was controlled from +40 C to -60 C at rates from steady state to + or - 65 C/min. Steady state temperature precision was better than 0.2 C while the dynamic capability depends on the temperature rate of change as well as the thermal mass of the sample and the container
Nonextensive Quantum H-Theorem
A proof of the quantum -theorem taking into account nonextensive effects
on the quantum entropy is shown. The positiveness of the time variation
of combined with a duality transformation implies that the nonextensive
parameter lies in the interval [0,2]. It is also shown that the equilibrium
states are described by quantum -power law extensions of the Fermi-Dirac and
Bose-Einstein distributions. Such results reduce to the standard ones in the
extensive limit, thereby showing that the nonextensive entropic framework can
be harmonized with the quantum distributions contained in the quantum
statistics theory.Comment: 5 pages, LaTe
Dictionary Learning-based Inpainting on Triangular Meshes
The problem of inpainting consists of filling missing or damaged regions in
images and videos in such a way that the filling pattern does not produce
artifacts that deviate from the original data. In addition to restoring the
missing data, the inpainting technique can also be used to remove undesired
objects. In this work, we address the problem of inpainting on surfaces through
a new method based on dictionary learning and sparse coding. Our method learns
the dictionary through the subdivision of the mesh into patches and rebuilds
the mesh via a method of reconstruction inspired by the Non-local Means method
on the computed sparse codes. One of the advantages of our method is that it is
capable of filling the missing regions and simultaneously removes noise and
enhances important features of the mesh. Moreover, the inpainting result is
globally coherent as the representation based on the dictionaries captures all
the geometric information in the transformed domain. We present two variations
of the method: a direct one, in which the model is reconstructed and restored
directly from the representation in the transformed domain and a second one,
adaptive, in which the missing regions are recreated iteratively through the
successive propagation of the sparse code computed in the hole boundaries,
which guides the local reconstructions. The second method produces better
results for large regions because the sparse codes of the patches are adapted
according to the sparse codes of the boundary patches. Finally, we present and
analyze experimental results that demonstrate the performance of our method
compared to the literature
Non-Gaussian effects on quantum entropies
AbstractA deduction of generalized quantum entropies within the non-Gaussian frameworks, Tsallis and Kaniadakis, is derived using a generalized combinatorial method and the so-called q and κ calculus. In agreement with previous results, we also show that for the Tsallis formulation the q-quantum entropy is well-defined for values of the nonextensive parameter q lying in the interval [0,2]
Tackling Fuel Poverty in London
The challenge of economic and health inequalities caused by fuel poverty are rooted in the rise in fuel costs which have strong implications affecting the cost of living. Fuel costs and rising inflation due to economic and political reasons threaten individuals and families who are already struggling financially, putting them in/at risk of fuel poverty. The UK is one of the first countries to define the challenge of households living in fuel poverty prompting necessary actions, policies and interventions.
This study presents the results of an empirical investigation following direct enquires to the Greater London Authority (GLA) and all of London boroughs via Freedom of Information (FOI) requests on retrofit interventions, including an overview of financial incentives and planning assessments with an aim to increase the number of home energy upgrades since April 2021.
London adopted its own action plan in 2018 to renew its focus and alleviate more than 350,000 households in fuel poverty (GLA, 2018). The assessment and indicator for fuel poverty has changed over time, from the Low Income High Cost (LIHC) to Low Income Low Energy Efficiency (LILEE) indicator in 2021. However, identifying households in fuel poverty remains challenging and some indicators are somewhat disconnected from what is happening on the ground. The findings suggest that there is a need to establish tools and methodologies that are connected to the national and local context. Fuel poverty is affecting people’s health and well-being, particularly those already facing socio-economic and health inequalities. After the COVID pandemic, a political awareness of fuel poverty is found in the Mayoral manifesto, however the Fuel Poverty Action Plan does not have binding targets and is not regularly updated. Current Fuel Poverty Partnership Tasks are focusing on awareness and communication or the urgent support to households already affected, but not in tackling the root causes of fuel poverty in upgrading fuel poor homes.
The uptake on retrofits from 2021 is still low and far from reaching 100k homes and the net zero target in 2030 is approaching fast. The study concludes that while LILEE is decreasing other indicators are increasing with rising energy prices. The London Building Stock Model is not widely used by boroughs, and it only maps the Energy Performance Certificate (EPC) rating which is not sufficient to identify households in fuel poverty. Most schemes such as Energy Companies Obligation (ECO) do not specifically target fuel poverty but have a wider scope of retrofit towards net zero. The Mayor of London should explore a new indicator tool by crossing data from LBSM with socio-economic data to identify fuel poor households more accurately. The indicator could potentially include geographical location, building typology (age, etc), socio-economic / demographics, leading to action plan and retrofit strategies
Assistive mobility devices focusing on smart walkers : classification and review
In an aging society it is extremely important to develop devices, which can support and aid the elderly in their daily life. This demands means and tools that extend independent living and promote improved health.
Thus, the goal of this article is to review the state of the art in the robotic technology for mobility assistive devices for people with mobility disabilities. The important role that robotics can play in mobility assistive devices is presented, as well as the identification and survey of mobility assistive devices subsystems with a particular focus on the walkers technology. The advances in the walkers’ field have been enormous and have shown a great potential on helping people with mobility disabilities. Thus it is presented a review of the available literature of walkers and are discussed major advances that have been made and limitations to be overcome
Planck Scale Physics and the Testability of SU(5) Supergravity GUT
GUT scale threshold corrections in minimal SU(5) supergravity grand
unification are discussed. It is shown that predictions may be made despite
uncertainties associated with the high energy scale. A bound relating the
strong coupling constant to the mass scales associated with proton decay and
supersymmetry is derived, and a sensitive probe of the underlying theory is
outlined. In particular, low energy measurements can in principle determine the
presence of Planck scale () terms.Comment: 12 pages, REVTeX, 2 figures included in an uuencoded Z-compressed
PostScript file. Ready to print PostScript version (with figures) may be
picked up at ftp://phys.tamu.edu/urano/planck/paper_prep.p
Review and classification of human gait training and rehabilitation devices
The number of people with reduced mobility capabilities increases every year.
This reduction arises mainly due to spinal cord injuries; strokes which caused hemiparesis;
or due to an advanced age. This decrease in mobility is a factor that influences
both their quality of life and their dependence of others in daily life.
Thus, it becomes necessary to find means and tools to prevent, compensate, improve
or help to restore and increase the mobility of the affected people. The main
expectation is that such means help to recover or ameliorate their independence in
their daily life. Traditional training employs a treadmill with a support-weight system.
This training is based on the principle of repetition of all the physical movements
of a gait and has shown to produce good results in terms of rehabilitation of
patients. However, this therapy requires two or more therapists in assisting patients
during walking, to hold and adjust the patient’s lower limbs to correctly produce the
desired gait. Thus, it requires a substantial commitment and effort of the therapists
[1], and it is very expensive in terms of human resources. This leads to a boost on
the population healthcare and assistive services demand and, thus an increase in the
need for care givers.
Assistive mobility robotic devices for gait training of disabled patients in treadmills
and in the ground are one successful alternative. Other alternatives include
devices that allow a broader training of patients, in different ground types, and the
repetition of gait movements in uphill, downhill and trip.
This paper reviews state of the art training gait devices focusing on passive and
active devices. Passive devices rely on the principle of Gravity-Balancing in that
they try to reduce or eliminate the effects of gravity during walking. Active devices
are usually classified according to three different approaches: (i) treadmillexoskeleton
based devices, (ii) robotic manipulators generating different types of
gait patterns, and (iii) mobilite devices. In this review, several examples of current
devices are presented
empires rituals and ceremonial pedagogy old and new
En el Imperio Romano, la función de crear parte de la cultura común necesaria para la ciudadanía, fue llevada a cabo por instituciones diferentes de lo que hoy llamamos «sistema escolar».Fue la sociedad antigua en su totalidad, a través de su vasto aparato ritual, la que proporcionó algo equivalente de lo que hoy llamamos «educación cívica».En el Imperio Romano universal, todos los ciudadanos eran educados por medio de esa «pedagogía ceremonial». Era una forma de educación colectiva, basada en símbolos y acciones para que los ciudadanos de las diversas identidades étnicas pudiesen «hablar» un lenguaje universal. Del mismo modo que la Iglesia Católica Romana (heredera de la universalidad del Imperio Romano) también ha utilizado el arte, la arquitectura, los rituales y los símbolos para educar a los fieles de todo el orbe.Hay un grupo de rituales romanos en particular (adventus, amburbium, lustrum), basados en majestuosas procesiones, cuyos vínculos con la educación de los ciudadanos son evidentes. El artículo explorará tales dimensiones educativas de los rituales, en lo que se cree que es una de sus formas supervivientes hoy, la procesión católica romana del santo patrón, la cual fue estudiada etnográficamente en un pueblo del centro de Italia.En Castelfiocco, un pueblo famoso por su campanilismo (fuerte sentimiento de pertenencia local), un sistema ritual basado en el culto a los santos, transmite a la población valores que sobreviven de un orden político más antiguo en el que el estado-nación moderno y global todavía no había aparecido. En este sistema tradicional, la dialéctica no es entre la localidad y la nación-estado, sino entre los miembros de la localidad y la universalidad de la Iglesia.La comprensión de algunos aspectos de tal dialéctica tradicional, y especialmente la comprensión de la forma en que se transmite a la población mediante rituales utilizados como pedagogía ceremonial, es de renovado interés en nuestra era de globalización
A Layman's guide to SUSY GUTs
The determination of the most straightforward evidence for the existence of
the Superworld requires a guide for non-experts (especially experimental
physicists) for them to make their own judgement on the value of such
predictions. For this purpose we review the most basic results of Super-Grand
unification in a simple and clear way. We focus the attention on two specific
models and their predictions. These two models represent an example of a direct
comparison between a traditional unified-theory and a string-inspired approach
to the solution of the many open problems of the Standard Model. We emphasize
that viable models must satisfy {\em all} available experimental constraints
and be as simple as theoretically possible. The two well defined supergravity
models, and , can be described in terms of only a few
parameters (five and three respectively) instead of the more than twenty needed
in the MSSM model, \ie, the Minimal Supersymmetric extension of the Standard
Model. A case of special interest is the strict no-scale
supergravity where all predictions depend on only one parameter (plus the
top-quark mass). A general consequence of these analyses is that supersymmetric
particles can be at the verge of discovery, lurking around the corner at
present and near future facilities. This review should help anyone distinguish
between well motivated predictions and predictions based on arbitrary choices
of parameters in undefined models.Comment: 25 pages, Latex, 11 figures (not included), CERN-TH.7077/93,
CTP-TAMU-65/93. A complete ps file (1.31MB) with embedded figures is
available by request from [email protected]
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