2,635 research outputs found
Finite Gluon Fusion Amplitude in the Gauge-Higgs Unification
We show that the gluon fusion amplitude in the gauge-Higgs unification
scenario is finite in any dimension regardless of its nonrenormalizability.
This result is supported by the fact that the local operator describing the
gluon fusion process is forbidden by the higher dimensional gauge invariance.
We explicitly calculate the gluon fusion amplitude in an arbitrary dimensional
gauge-Higgs unification model and indeed obtain the finite result.Comment: 15 pages, final version to appear in MPL
Ethical issues in assistive ambient living technologies for ageing well
Assistive Ambient Living (AAL) in ageing refers to any device used to support ageing related psychological and physical changes aimed at improving seniors’ quality of life and reducing caregivers’ burdens. The diffusion of these devices opens the ethical issues related to their use in the human personal space. This is particularly relevant when AAL technologies are devoted to the ageing population that exhibits special bio-psycho-social aspects and needs. In spite of this, relatively little research has focused on ethical issues that emerge from AAL technologies. The present article addresses ethical issues emerging when AAL technologies are implemented for assisting the elderly population and is aimed at raising awareness of these aspects among healthcare providers. The overall conclusion encourages a person-oriented approach when designing healthcare facilities. This process must be fulfilled in compliance with the general principles of ethics and individual nature of the person devoted to. This perspective will develop new research paradigms, paving the way for fulfilling essential ethical principles in the development of future generations of personalized AAL devices to support ageing people living independently at their home
Simple and Realistic Composite Higgs Models in Flat Extra Dimensions
We construct new composite Higgs/gauge-Higgs unification (GHU) models in flat
space that overcome all the difficulties found in the past in attempting to
construct models of this sort. The key ingredient is the introduction of large
boundary kinetic terms for gauge (and fermion) fields. We focus our analysis on
the electroweak symmetry breaking pattern and the electroweak precision tests
and show how both are compatible with each other. Our models can be seen as
effective TeV descriptions of analogue warped models. We point out that, as far
as electroweak TeV scale physics is concerned, one can rely on simple and more
flexible flat space models rather than considering their unavoidably more
complicated warped space counterparts. The generic collider signatures of our
models are essentially undistinguishable from those expected from composite
Higgs/warped GHU models, namely a light Higgs, colored fermion resonances below
the TeV scale and sizable deviations to the Higgs and top coupling.Comment: 30 figures, 9 figures; v2: minor improvements, one reference added,
version to appear in JHE
Thermal Modeling of a Historical Building Wall: Using Long-Term Monitoring Data to Understand the Reliability and the Robustness of Numerical Simulations
Thermal modeling of building components plays a crucial role in designing energy efficiency measures, assessing living comfort, and preventing building damages. The accuracy of the modeling process strongly depends on the reliability of the physical models and the correct selection of input parameters, especially for historic buildings where uncertainties on wall composition and material properties are higher. This work evaluates the reliability of building thermal modeling and identifies the input parameters that most affect the simulation results. A monitoring system is applied to a historic building wall to measure the temperature profile. The long-term dataset is compared with the result of a simulation model. A sensitivity analysis is applied for the determination of the influential input parameters. A two-step optimization is performed to calibrate the numerical model: the first optimization step is based on an optimized selection of the database materials, while the second optimization step uses a particle swarm algorithm. The results indicate that the output of the simulation model is largely influenced by the coefficients describing the coupling with the boundary conditions and by the thermal conductivities of the materials. Very good results are obtained already after the first optimization step ((Formula presented.) while the second optimization step improves further the agreement ((Formula presented.). The parameter values reported in the datasheets do not match those found through optimization. Even with extensive optimization using an algorithm, starting with monitoring data is insufficient to identify material parameter values
Plant cover and management practices as drivers of soil quality
Human activities intensively modify soil properties and quality according to land-use and management practices. In Mediterranean areas, pollution and fires may directly alter some soil abiotic properties as well as the steady-state condition of soil microbiota. The aim of this study was to evaluate if the chemical and biological characteristics of two kinds of soil, Arenosols and Andosols, of a natural reserve and an urban park respectively, were affected by the same or different plant covers (trees and grasses). At each site, five sub-samples of surface soils (0–10 cm) were collected under maquis (trees) and gap of grasses. The soils were analyzed for physico-chemical parameters (organic matter and water contents, pH, C, N, Cr, Cu, Ni and Pb concentrations) and biological parameters (microbial and fungal biomass, respiration, metabolic quotient and coefficient of endogenous mineralization). The soil quality was evaluated through an integrated index, calculated taken into account all the investigated parameters. The results highlighted that soils under trees inside the urban park, with the highest amount of organic matter, showed higher microbial biomass and activity as compared to soils under grasses. The high concentration of Cu and Pb in these latter soils inhibited the microbial biomass and activity that were not exclusively affected by litter quality. Soil quality would seem to be strongly affected by the pedogenetic derivation and the management practices more than plant covers
On electroweak baryogenesis in the littlest Higgs model with T parity
We study electroweak baryogenesis within the framework of the littlest Higgs
model with T parity. This model has shown characteristics of a strong
first-order electroweak phase transition, which is conducive to baryogenesis in
the early Universe. In the T parity symmetric theory, there are two gauge
sectors, viz., the T-even and the T-odd ones. We observe that the effect of the
T-parity symmetric interactions between the T-odd and the T-even gauge bosons
on gauge-higgs energy functional is quite small, so that these two sectors can
be taken to be independent. The T-even gauge bosons behave like the Standard
Model gauge bosons, whereas the T-odd ones are instrumental in stabilizing the
Higgs mass. For the T-odd gauge bosons in the symmetric and asymmetric phases
and for the T-even gauge bosons in the asymmetric phase, we obtain, using the
formalism of Arnold and McLerran, very small values of the ratio, (Baryon
number violation rate/Universe expansion rate). We observe that this result, in
conjunction with the scenario of inverse phase transition in the present work
and the value of the ratio obtained from the lattice result of sphaleron
transition rate in the symmetric phase, can provide us with a plausible
baryogenesis scenario.Comment: 13 pages, 2 figures, published version, references modifie
Variation of the chemical and biological properties of a Technosol during seven years after a single application of compost
Technosols are composed of natural soils mixed with artificial materials and can be an inhospitable environment for the soil microbial community. The main goal of the current research was to evaluate temporal variations of Technosol quality through an integrated approach, considering all of the evaluated chemical, physical and biological characteristics for a period of seven years after a single application of compost. The soil samples were evaluated using the following parameters: pH; water content; water holding capacity; bulk density; porosity; organic matter and N contents; C/N ratio; fungal biomass; microbial biomass; respiration; metabolic quotient (qCO 2 ); and endogenous mineralisation coefficient (CEM). The overall evaluation showed that a single application of compost improved the soil quality in the short term. A decrease in Technosol quality over the long term appears to be due to deterioration of the physical and chemical properties, rather than a change in biological properties
Eco-Sustainable Energy Production in Healthcare: Trends and Challenges in Renewable Energy Systems
The shift from fossil fuels to renewable energy systems represents a pivotal step toward the realization of a sustainable society. This study aims to analyze representative scientific literature on eco-sustainable energy production in the healthcare sector, particularly in hospitals. Given hospitals’ substantial electricity consumption, the adoption of renewable energy offers a reliable, low-CO2 emission solution. The COVID-19 pandemic has underscored the urgency for energy-efficient and environmentally-responsible approaches. This brief review analyzes the development of experimental, simulation, and optimization projects for sustainable energy production in healthcare facilities. The analysis reveals trends and challenges in renewable energy systems, offering valuable insights into the potential of eco-sustainable solutions in the healthcare sector. The findings indicate that hydrogen storage systems are consistently coupled with photovoltaic panels or solar collectors, but only 14% of the analyzed studies explore this potential within hospital settings. Hybrid renewable energy systems (HRES) could be used to meet the energy demands of healthcare centers and hospitals. However, the integration of HRES in hospitals and medical buildings is understudied
Metabolic syndrome and postmenopausal breast cancer in the ORDET cohort : a nested case-control study
Background and aims: The increase in breast cancer incidence over recent decades has been accompanied by an increase in the frequency of metabolic syndrome. Several studies suggest that breast cancer risk is associated with the components of metabolic syndrome (high serum glucose and triglycerides, low HDL-cholesterol, high blood pressure, and abdominal obesity), but no prospective study has investigated risk in relation to the presence of explicitly defined metabolic syndrome. We investigated associations between metabolic syndrome, its components, and breast cancer risk in a nested case-control study on postmenopausal women of the ORDET cohort. Methods and results: After a median follow-up of 13.5 years, 163 women developed breast cancer; metabolic syndrome was present in 29.8%. Four matched controls per case were selected by incidence density sampling, and rate ratios were estimated by conditional logistic regression. Metabolic syndrome (i.e. presence of three or more metabolic syndrome components) was significantly associated with breast cancer risk (rate ratio 1.58 [95% confidence interval 1.07-2.33]), with a significant risk increase for increasing number of components (P for trend 0.004). Among individual metabolic syndrome components, only low serum HDL-cholesterol and high triglycerides were significantly associated with increased risk. Conclusions: This prospective study indicates that metabolic syndrome is an important risk factor for breast cancer in postmenopausal women. Although serum HDL-cholesterol and triglycerides had the strongest association with breast cancer, all components may contribute to increased risk by multiple interacting mechanisms. Prevention or reversal of metabolic syndrome by life-style changes may be effective in preventing breast cancer in postmenopausal women
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