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• Different strategies are analyzed to enhanced microchannels based heat sinks. • Nanofluids to enhance heat performance of microchannel based heat sinks is analyzed. • Experiments are performed for Al 2 O 3 , Au and Ag nanoparticles at various concentrations. • The flow-boiling regimes are identified and discussed for the working conditions considered. • Two-phase flow conditions may not always be beneficial, low concentrations of nanoparticles (ϕ ≪ 1%) can have a notable impact on heat transfer mechanisms. This paper investigates the advantages and challenges associated with two-phase flows, specifically flow boiling of pure liquids and nanofluids, for cooling applications in microchannel heat sinks. The study explores various two-phase flow patterns, their related issues, and examines the potential of nanoparticles to enhance heat transfer. Alumina (Al 2 O 3), gold (Au), and silver (Ag) nanoparticles at different concentrations were tested. Experimental tests were conducted under different working conditions using various working fluids, including water, Al 2 O 3 1 wt%, Ag 1 wt%, Au 1 wt%, Au 0.75 wt%, Au 0.5 wt%. The heat fluxes used were 1.026 kW/m2, 1.696 W/m2 and 2.403 kW/m2, while the volumetric flows ranged between 0.5 mL/min and 1.5 mL/min. The observed results indicate that even for the lowest particle concentration tested, the water-Au nanofluid exhibits superior cooling performance compared to the other examined fluids. The findings suggest that although two-phase flow conditions may not yield significant benefits, even small concentrations of nanoparticles (ϕ ≪ 1%) can significantly impact heat transfer mechanisms. This approach provides a cost-effective and efficient alternative for cooling microchannel heat sinks without necessitating the use of two-phase flow conditions. [ABSTRACT FROM AUTHOR]

The adverse effects of Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) are not limited to the related infectious disease. In children and adolescents, serious risks due to the coronavirus disease 2019 (COVID-19) pandemic are also related to its indirect effects. These include an unbalanced diet with an increased risk of weight excess or nutritional deficiencies, increased sedentary lifestyle, lack of schooling, social isolation, and impaired mental health. Pediatricians should be aware of the side effects of the COVID-19 pandemic on children's diet, physical mental health and advise the families according to their nutritional needs and financial resources. Moreover, the lack of a targeted therapy able to offer protection against the deleterious effects of SARS-CoV-2 infection should require a greater effort by scientific societies to find a more effective prevention strategy. In this context, much interest should be given to nutritional support, able to contrast malnutrition and to stimulate the immune system. [ABSTRACT FROM AUTHOR]

Background: Physicians play a key role in driving vaccine acceptance and their recommendations are crucial to address vaccine hesitancy. The aim of the study was to assess knowledge, awareness and attitude of Italian Pediatric Health Care Professionals (pHCPs) on vaccinations. Methods: An anonymous on-line questionnaire was developed within the Vaccine Committee of Italian Society of Pediatric Allergy and Immunology (SIAIP) and spontaneously completed by 231 Pediatricians and Pediatric Nurses (PN). Results: An accurate vaccine education was reported by 70% of pediatricians and 13% of PN but 11% of pediatricians versus 26% of PN consult social media instead of scientific sources for their vaccine update. The investigation on the pHCPs attitudes to vaccination in a personal and family setting highlights poor adherence to vaccinations. Only 63% of pediatricians versus 16% of PN (p < 0.0001) annually received the Flu vaccine. In their family setting 93% of pediatricians versus 51% of PN recommended all vaccinations (p < 0.0001). Anti-flu, anti-rotavirus, anti-zoster and anti-pneumococcal vaccines were not regularly recommended by all pHCPs due to doubts of uselessness (55% of pediatricians versus 40% of PN) and preference for "natural immunity" (44% of pediatricians versus 40% of PN). Conclusions: Our results indicate that pHCPs' attitude and confidence in regards to vaccines remain suboptimal. Current COVID-19 pandemic and the rapid development of vaccines could increase vaccine hesitancy. Due to the documented pHCPs' influence in the parental decision, educational interventions are needed to improve their level of knowledge and counselling skills in order to address parental vaccine hesitancy and to maintain continuity of immunization services. [ABSTRACT FROM AUTHOR]

In order to evaluate the infectious agents associated with the first episode of severe acute wheezing in otherwise healthy infants and to define the role of each of them in recurrences, 85 patients in Italy, aged <12 months, hospitalized because of a first acute episode of wheezing, were prospectively enrolled between 1 October 2005 and 31 March 2006. Upon enrolment, nasopharyngeal swabs were collected for the real-time PCR detection of respiratory syncytial virus (RSV) types A and B, influenza virus types A and B, adenovirus, parainfluenza viruses types 1, 2, 3 and 4, rhinovirus, human metapneumovirus, human coronavirus types 229E, OC43, NL63, and HKU1, bocavirus, enterovirus, and paraechovirus; nasopharyngeal aspirates were also obtained to detect atypical bacteria. At least one infectious agent was identified in 76 children (89.4%). RSV was the most frequently detected pathogen and its prevalence was significantly higher than that of the other pathogens in both age groups, and significantly higher in the children aged 3–12 months than in those aged <3 months. Only the children with RSV infection experienced recurrent wheezing. Viral load was significantly higher in children with than in those without recurrent wheezing. This study shows that RSV is the main reason for hospitalization during the first wheezing episode in infants, and that it appears to be the only pathogen associated with a high frequency of recurrences. A high viral load seems to be strictly related to the likelihood of recurrence. [ABSTRACT FROM AUTHOR]