Innovative Adsorption Heat Exchangers for Desiccant Cooling and Atmospheric Water Harvesting

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On the symmetric rearrangement of the gradient of a Sobolev function

In this paper, we generalize a classical comparison result for solutions to Hamilton-Jacobi equations with Dirichlet boundary conditions, to solutions to Hamilton-Jacobi equations with non-zero boundary trace. As a consequence, we prove the isoperimetric inequality for the torsional rigidity (with Robin boundary conditions) and for other functionals involving such boundary conditions

Air Cooling and Dehumidification with a zeolite coated heat exchanger regenerated by Solar thermal energy

This paper presents some experimental results of a new device for low energy/low exergy air conditioning system. The device can realize both dehumidification and sensible cooling of external air, and it is designed for very low pressure drops, drastically reducing the electricity consumption for the driving fans. It is composed by a finned coil heat exchanger, coated with a SAPO-34 zeolite layer, that handles both heat and mass transfer in a single component. During the adsorption a cold water flow at 20 °C circulates through the coil, cooling the air and realizing in a single step a complete air-treatment. Hot water produced with evacuated solar collector is then used to regenerate the zeolite

Results, questions, perspectives of a study on human polyomavirus BK and molecular actors in prostate cancer development

Background: Prostate cancer (PC) is a common tumor in Western countries. Several risk factors play significant roles. MYC, BIRC5/survivin, CDC25 and P53 may contribute to PC risk. As demonstrated, human Polyomavirus BK (BKV) could affect cellular homeostasis contributing to PC pathogenesis. Materials and Methods: Biological samples were collected from PC patients. Viral RNA was searched using quantitative polymerase chain reaction (PCR), whereas a qualitative PCR was employed to find particular viral sequences. Proper size amplicons were analyzed. Single nucleotide polymorphisms (SNPs) were detected in p53 coding regions by means of a specific PCR. C-MYC, BIRC5/survivin and CDC25 gene expression was investigated using a Retro Transcriptional Quantitative PCR. Results: Viral DNA copy number was higher in cancer tissues taken from Gleason score 9 patients with Gleason score 7. Different p53 mutated compared to patients exons were found according to tumor advanced stage and a statistical significant correlation was found between Gleason score and p53 mutational rate. C-MYC, BIRC5/survivin and CDC25 expression was de-regulated according to the literature. Conclusion: The presence of BKV and its variants in transformed cells does not exclude viral pressure in cell immortalization. Expression of other target genes evidenced a significant change in their regulation, useful for cancer drug discovery and therapies

Local control of near-field diffusion of infected respiratory cloud in a room by air-blades

The respiratory cloud of an infective subject contains droplets of mucosalivary fluid carrying pathogens. As this cloud spreads at a certain distance from the emission point, the droplets accumulate and their volume concentration increases in the room unless dilution, adequate ventilation, or filtration reduce it. A susceptible subject, standing a short distance away can be exposed more easily to the infected respiratory cloud, thus inhaling a higher dose of pathogens than someone breathing the mixed air in the room. A local airflow pattern can be employed to reduce this short-distance risk of inhalation and potential contagion. We present experimental and numerical investigations of a novel device acting as a barrier to airborne pathogen diffusion at a short distance. This portable device generates V-shaped air blades in front of the subjects, shifting the respiratory clouds. The air blades are generated by 12 small fans, three on each side of the cube. The air is sucked into the small plenum inside the device body through the bases. By being positioned obliquely on a meeting table, the device acts as a direct barrier to virus-laden aerosols without any filtration. The experimental tests show that the system can reduce the local concentration of aerosol by 63 to 84% at the respiratory position of a subject sitting at a table in front of an infective person. CFD simulation outputs using the Multiphase Eulerian-Lagrangian model show a good agreement with the experimental results. The validated model will be used to extend the range of investigation to different settings and to perform a parametrical analysis of the main design conditions

Sustainable finance disclosure regulation insights: Unveiling socially responsible funds performance during COVID‐19 pandemic and Russia–Ukraine war

The transition towards a more sustainable financial market demands transparency andtrust from investors, objectives also pursued by the Sustainable Finance DisclosureRegulation (SFDR). Specifically, carefully assessing the risk-adjusted performance ofsustainable funds empowers investors to make informed decisions in alignment withtheir ethical and financial objectives. This article contributes to the debate on the per-formance of socially responsible investment (SRI) funds in times of crisis by evaluatingthe risk-adjusted performance of a sample of SRI and conventional funds, ranked inlight of the SFDR, during the COVID-19 pandemic and the Russia–Ukraine war. Usinga two-step analysis, the results of the study show that funds with clear sustainabilityobjectives, as defined by Article 9 of the SFDR, were able to outperform conventionalfunds, but only a few months after the onset of the crisis periods, thus demonstratingpoor performance persistence. At the same time, sustainable funds with a focus onfinancial materiality, as defined by Article 8, were never able to generate significantlydifferent risk-adjusted performance from conventional funds. Our results show thatthe lack of performance persistence of Article 9 funds prevents an effective hedgingrole for investment strategies that consider extra-financial criteria. They also confirmthat the classification criteria introduced by the SFDR still need to be more specificand create more transparency in financial market

Designing Health Structure in Emergency Contexts. Natural Ventilation as Response to COVID-19 Pandemic.

The importance of ventilation as response to pandemic emergency is a concept that trace its roots back in the history of human pandemic and it remains valid up to the current covid-19 emergency. Yet, extreme climates, scarcity of resources, and poverty might impinge heavily on the ability of designing a built environment fit for the purpose of guarantee environmental conditions appropriate to respond to pandemic. Often, in contexts of scarcity and hot climates, safety parameters of ventilation in buildings are achieved as ersatz, rather than by design, due to the difficulties of managing economic resources, thermal characteristic, and ventilation requirements. Keep buildings cool and well ventilated seems to be still a challenge. This work presents a study carried out to design health structures - both permanent and temporary - in response to covid-19, in the Global South. Specifically, the study focused on: 1) the design of a Severe Acute Respiratory Infection (SARI) Treatment Center (hospital for airborne diseases) in the city of Dori in Burkina Faso, and 2) the design and test of High Performance Tents. Natural ventilation is studied by mean of transient dynamic simulations, using Energy+ software, and the probability of contagion are evaluated applying the Gammaitoni-Nucci model, based on the original Wells and Riley approach. The yearly dynamic simulations are supported by specific 3D airflows analysis by mean of CFD (Computational Fluid Dynamic), with the intent to underline the effects of different internal partitions configuration. CFD is also used to evaluate pressure coefficient at the openings. Through this ventilation study and morphological design proposal, this work provides compositional, technological and environmental solutions to overcome limits due to the need of coexistence of ventilation and thermal control, and socio-economic limitations. The significance of this work is the ability to show the importance of the balance between passive ventilation, architectural design and behavioral organization by design. Such approach can play a critical factor to achieve healthy and resilient environment, and offer a feasible solution to the need for health buildings in hot climates and poor contexts

On the gradient rearrangement of functions

In this paper, we introduce a symmetrization technique for the gradient of a \BV function, which separates its absolutely continuous part from its singular part (sum of the jump and the Cantorian part). In particular, we prove an \text{\emph{L}}^{\text{1}} comparison between the function and its symmetrized. Furthermore, we apply this result to obtain Saint-Venant type inequalities for some geometric functionals