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Optical emission spectroscopic investigations of the plasma produced during KrF excimer laser ablation of Zn and ZnO targets, in vacuum and in oxygen gas environment, are presented. The plume luminescence is mainly due to Zn excited atoms and ions, but the contribution of atomic and molecular oxygen, as well as of particulates, cannot be neglected. In particular, we detect emissions in the spectral regions around 380 and 530 nm, corresponding to the UV and green photo-luminescence bands of the zinc oxide. Moreover, we study the temporal evolution of atomic and ionic ejected species by space- and time-resolved spectroscopy and analyze the results by means of empirical models, in order to infer information about plasma dynamics. [ABSTRACT FROM AUTHOR]

Abstract: The laser-induced breakdown spectroscopy technique is employed for compositional analyses of thin films produced by pulsed laser ablation of multielemental targets. Information about the atomic concentration of the chemical species from the irradiated target is inferred by means of the optical emission spectra of the plasma generated during laser ablation. The atomic concentration percentages and the atomic concentration ratios of the elements of Co-based magnetic alloy targets are deduced from the integrated intensities of selected emission lines of the alloy components. The experimental results show that Co atomic percentage concentration and CSi/CCo and CCr/CCo atomic concentration ratios are in agreement with the corresponding values obtained by traditional compositional analysis techniques. On the contrary, Si atomic percentage concentration values are in disagreement, since the used emission lines have significant self-absorption values. Therefore, the work proves that laser-induced breakdown spectroscopy is adequate for elemental concentration measurements provided an accurate choice of the emission lines. [Copyright &y& Elsevier]

Some emission spectra of diatomic molecules were calculated by a semi-automatic programme package in order to infer the rotational and vibrational temperatures in Boltzmann distribution by comparing them with the corresponding experimental ones. The calculation procedure was applied in the case of CN radical and C2 molecule whose optical emission spectra were recorded during pulsed excimer laser ablation of a graphite target in low-pressure nitrogen environment. Computed similar or dissimilar values of rotational and vibrational temperatures let to verify the existence or not of local thermodynamic equilibrium and to hypothesise the temporal range necessary to establish it in such experiments. [Copyright &y& Elsevier]

Several experiments were carried out during pulsed laser deposition (PLD) of semimagnetic semiconductor (SMS) films in order to identify the contributions of the target and/or the substrate and/or the plume effects on the incongruent material transfer in the Cd1−xMnxTe film deposition on heated substrates. During XeCl laser ablation of a Cd1−xMnxTe target (x=0.50) at 6 J/cm2 fluence, films were deposited onto unheated substrates at different collecting angles with respect to the plume expansion direction. In the same time, the angular distribution of the emitting chemical species in the plasma was investigated by a combination of wavelength, temporal and spatial resolved optical emission spectroscopic measurements. Film composition was analysed by energy dispersion X-ray spectroscopy (EDS) and Rutherford backscattering spectrometry (RBS). Results are used as the basis for a study of the processes that control the stoichiometry of the deposited semimagnetic semiconductor films. [Copyright &y& Elsevier]

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is associated with a high rate of mortality in kidney transplant recipients (KTRs). Current vaccine strategies for KTRs seem to be unable to provide effective protection against coronavirus disease 2019 (COVID-19), and the occurrence of severe disease in some vaccinated KTRs suggested a lack of immunity. We initially analyzed the antibody response in a group of 32 kidney transplant recipients (KTRs) followed at the nephrology and dialysis unit of the Hospital Pio XI of Desio, ASST-Brianza, Italy. Thus, we studied the differences in antibody levels between subjects who contracted SARS-CoV-2 after the booster (8 individuals) and those who did not contract it (24 individuals). Furthermore, we verified if the antibody response was in any way associated with creatinine and eGFR levels. We observed a significant increase in the antibody response pre-booster compared to post-booster using both a Roche assay and DIAPRO assay. In the latter, through immunotyping, we highlight that the major contribution to this increase is specifically due to IgG S1 IgM S2. We observed a significant increase in IgA S1 and IgA NCP ( p = 0.045, 0.02) in the subjects who contracted SARS-CoV-2. We did not find significant associations for the p -value corrected for false discovery rate (FDR) between the antibody response to all assays and creatinine levels. This observation allows us to confirm that patients require additional vaccine boosters due to their immunocompromised status and therapy in order to protect them from infections related to viral variants. This is in line with the data reported in the literature, and it could be worthwhile to deeply explore these phenomena to better understand the role of IgA S1 and IgA NCP antibodies in SARS-CoV-2 infection.

Coronavirus disease 2019 (COVID-19) is a respiratory disease caused by severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2). It is acknowledged that vulnerable people can suffer from mortal complications of COVID-19. Therefore, strengthening the immune system particularly in the most fragile people could help to protect them from infection. First, general nutritional status and food consumption patterns of everyone affect the effectiveness of each immune system. The effects of nutrition could impact the level of intestinal and genital microbiota, the adaptive immune system, and the innate immune system. Indeed, immune system cells and mediators, which are crucial to inflammatory reaction, are in the structures of fats, carbohydrates, and proteins and are activated through vitamins (vit) and minerals. Therefore, the association of malnutrition and infection could damage the immune response, reducing the immune cells and amplifying inflammatory mediators. Both amount and type of dietary fat impact on cytokine biology, that consequently assumes a crucial role in inflammatory disease. This review explores the power of nutrition in the immune response against COVID-19 infection, since a specific diet could modify the cytokine storm during the infection phase. This can be of vital importance in the most vulnerable subjects such as pregnant women or cancer patients to whom we have deemed it necessary to dedicate personalized indications.