Molecular Bremsstrahlung Radiation at GHz Frequencies in Air

A detection technique for ultra-high energy cosmic rays, complementary to the fluorescence technique, would be the use of the molecular Bremsstrahlung radiation emitted by low-energy ionization electrons left after the passage of the showers in the atmosphere. In this article, a detailed estimate of the spectral intensity of photons at ground level originating from this radiation is presented. The spectral intensity expected from the passage of the high-energy electrons of the cascade is also estimated. The absorption of the photons in the plasma of electrons/neutral molecules is shown to be negligible. The obtained spectral intensity is shown to be $2\times10^{-21}$W cm$^{-2}$ GHz$^{-1}$ at 10 km from the shower core for a vertical shower induced by a proton of $10^{17.5}$ eV. In addition, a recent measurement of Bremsstrahlung radiation in air at gigahertz frequencies from a beam of electrons produced at 95 keV by an electron gun is also discussed and reasonably reproduced by the model.Comment: 20 pages, 9 figures, figures (2,4,7) improved in v2, accepted by Phys. Rev.

Challenges in IAQ for Indoor Spaces: A Comparison of the Reference Guideline Values of Indoor Air Pollutants from the Governments and International Institutions

Since people spend most of their time inside buildings, indoor air quality (IAQ) remains a highlighted topic to ensure in the built environment to improve public health, especially for vulnerable users. To achieve a better indoor environment quality (IEQ), some countries’ governments or regional institutions have developed and published reference guideline values of various air pollutants to prevent the IAQ from becoming adverse to occupants. Beyond guidelines by World Health Organization (WHO), in some countries, there are specific institutional requirements on the IAQ, and others integrated it into the building regulation for the built environment. This paper is based on the literature research, summarized from previously conducted works by the authors, on the chemical reference values of IAQ-related regulations and guidelines published by several Governments or related institutions from various regions around the World. Despite these efforts at standardization and legislation, many indoor air quality monitoring activities conducted in several countries still fall short of the main indications produced. By comparing the reference values of 35 pollutants, both physical and chemical ones, which are proposed in documents from 23 regions included so far, the IAQ research and prevention actions on progress in different regions should be included in monitoring plans with guidelines/reference values in their current state. The outcome of the paper is to define the current trends and suggest some perspectives on the field of interest for improving the indoor air quality of generic spaces at an international level. It becomes evident that, at the global level, IAQ represents a complex political, social, and health challenge, which still suffers from the absence of a systematic and harmonized approach. This is not a new situation; the issue was raised more than 40 years ago, and despite efforts and a pandemic, the situation has not changed

COVID-19 and living space challenge. Well-being and public health recommendations for a healthy, safe, and sustainable housing

Background and aim of the work: The ongoing pandemic of COVID-19 is a strong reminder that the lockdown period has changed the way that people and communities live, work, and interact, and it’s necessary to make resilient the built environment, both outdoor and mainly the indoor spaces: housing, workplaces, public buildings, and entertainment facilities. How can we re-design the concept of Well-being and Public Health in relation to the living places of the future? Methods: According to the previous statements and scenario, this paper aims to integrate the building hygiene and well-being, focusing the possible responses, both existing and for the new buildings, taking home a strong message from this “period” of physical distancing. Results: The Well-being and Public Health recommendations for a healthy, safe, and sustainable housing are framed into the following key points: 1. Visible and accessible green elements and spaces; 2. Flexibility, adaptability, sharing, and crowding of living spaces, and compliant functions located into the buildings; 3. Re-appropriation of the basic principles and archetypes of sustainable architecture, thermal comfort and Indoor Air Quality (IAQ); 4. Water consumption and Wastewater Management; 5. Urban Solid Waste Management; 6. Housing automation and electromagnetic fields; 7. Indoor building and finishing materials. Conclusions: The Well-being and Public Health recommendations for a healthy, safe and sustainable housing may provide a useful basis for Designers, Policy Makers (fostering tax incentives for building renewal), Public Health experts and Local Health Agencies, in promoting actions and policies aimed to transform living places in healthier and Salutogenic spaces. (www.actabiomedica.it)

A proposal of hygienic and sanitary standards for the new Building Code in Italy

The traditional emphasis of Public Health on the type and quality of housing today merges with other wider determinants of health such as: the neighbourhood, the community and the "place" where a home is located, but also the policies that make access to a healthy home within everyone's reach. At the neighbourhood scale, context-related aspects heavily influence the internal quality and real usability of the buildings themselves, with particular reference to factors such as the quality of the site, the relationship between the building and the context, the presence and quality of the greenery and open spaces surrounding the building, as well as all measures that make it possible to reduce the building's impact on the environment, to protect it against environmental pollution, and to manage the building in an integrated manner for maintenance purposes. Creating healthy living environments means referring to the different dimensions mentioned above, and this not only requires the attention of Public Health operators, but also implies an integration of vision and objectives among various professional skills and competences that puts health at the center of all policies. This proposal, which starts from the analysis of existing local hygiene regulations and scientific literature, aims to take stock of a number of areas considered fundamental for the assessment of building hygiene aspects, with particular reference to the eco-sustainability of buildings and adaptation to climate change. The aspects identified can be considered as a starting point for the preparation of integrated building and hygiene regulations based on documented effective practices for the protection of Public Health

Towards an update of the Italian Ministerial Decree July 5th, 1975

In recent years, the Scientific Community and the Public Health world, in general, have devoted increasing interest to housing conditions, which are considered, to date, one of the main environmental and social determinants of the population's health. In particular, the Scientific Community has identified and studied various indoor well-being factors (e.g. lighting, temperature, ventilation, air quality, etc.). Some of these factors have been regulated by laws and regulations at various levels: the availability of clear and updated health requirements dictated by the regulations is fundamental to effectively protect public health, especially in confined environments. In the present work, we propose a revision of the Italian Ministerial Decree of July 5th, 1975 titled Modificazioni alle istruzioni ministeriali 20 giugno 1896 relativamente all'altezza minima ed ai requisiti igienico sanitari principali dei locali d'abitazione (Modifications to the ministerial instructions of June 20th, 1896 regarding the minimum height and the main hygienic-sanitary requirements of living spaces) in order to update the definition of the essential elements that qualify a space as habitable from the hygienic-sanitary point of view, taking into account the evidence gathered from the technical and scientific literature on the requirements and contents of the Building Codes of the major European countries

Sampling protein motion and solvent effect during ligand binding.

An exhaustive description of the molecular recognition mechanism between a ligand and its biological target is of great value because it provides the opportunity for an exogenous control of the related process. Very often this aim can be pursued using high resolution structures of the complex in combination with inexpensive computational protocols such as docking algorithms. Unfortunately, in many other cases a number of factors, like protein flexibility or solvent effects, increase the degree of complexity of ligand/protein interaction and these standard techniques are no longer sufficient to describe the binding event. We have experienced and tested these limits in the present study in which we have developed and revealed the mechanism of binding of a new series of potent inhibitors of Adenosine Deaminase. We have first performed a large number of docking calculations, which unfortunately failed to yield reliable results due to the dynamical character of the enzyme and the complex role of the solvent. Thus, we have stepped up the computational strategy using a protocol based on metadynamics. Our approach has allowed dealing with protein motion and solvation during ligand binding and finally identifying the lowest energy binding modes of the most potent compound of the series, 4-decyl-pyrazolo[1,5-a]pyrimidin-7-one

Pharmacological characterization of a new Ca2+ sensitizer

The benzimidazole molecule was modified to synthesize a Ca(2+) sensitizer devoid of additional effects associated with Ca(2+) overload. Newly synthesized compounds, termed 1, 2, 3, 4, and 5, were evaluated in spontaneously beating and electrically driven atria from reserpine-treated guinea pigs. Compound 3 resulted as the most effective positive inotropic agent, and experiments were performed to study its mechanism of action. In spontaneously beating atria, the inotropic effect of 3 was concentration-dependent (3.0 microM-0.3 mM). Compound 3 was more potent and more active than the structurally related Ca(2+) sensitizers sulmazole and caffeine, but unlike them it did not increase the heart rate. In electrically driven atria, the inotropic activity of 3 was well preserved and it was not inhibited by propranolol, prazosin, ranitidine, pyrilamine, carbachol, adenosine deaminase, or ruthenium red. At high concentrations (0.1-1.0 mM) 3 inhibited phosphodiesterase-III, whereas it did not affect Na(+)/K(+)-ATPase, sarcolemmal Ca(2+)-ATPase, Na(+)/Ca(2+) exchange carrier, or sarcoplasmic reticulum Ca(2+) pump activities of guinea pig heart. In skinned fibers obtained from guinea pig papillary muscle and skeletal soleus muscle, compound 3 (0.1 mM, 1 mM) shifted the pCa/tension relation curve to the left, with no effect on maximal tension and no signs of toxicity. Compound 3 did not influence the basal or raised tone of guinea pig isolated aorta rings, whose cells do not contain the contractile protein troponin. The present results indicate that the inotropic effect of compound 3 seems to be primarily sustained by sensitization of the contractile proteins to Ca(2+)

The Air Microwave Yield (AMY) experiment - A laboratory measurement of the microwave emission from extensive air showers

The AMY experiment aims to measure the microwave bremsstrahlung radiation (MBR) emitted by air-showers secondary electrons accelerating in collisions with neutral molecules of the atmosphere. The measurements are performed using a beam of 510 MeV electrons at the Beam Test Facility (BTF) of Frascati INFN National Laboratories. The goal of the AMY experiment is to measure in laboratory conditions the yield and the spectrum of the GHz emission in the frequency range between 1 and 20 GHz. The final purpose is to characterise the process to be used in a next generation detectors of ultra-high energy cosmic rays. A description of the experimental setup and the first results are presented.Comment: 3 pages -- EPS-HEP'13 European Physical Society Conference on High Energy Physics (July, 18-24, 2013) at Stockholm, Swede