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Compression ignition engines will still be predominant in the naval sector: their high efficiency, high torque, and heavy weight perfectly suit the demands and architecture of ships. Nevertheless, recent emission legislations impose limitations to the pollutant emissions levels in this sector as well. In addition to post-treatment systems, it is necessary to reduce some pollutant species, and, therefore, the study of combustion strategies and new fuels can represent valid paths for limiting environmental harmful emissions such as CO2. The use of methane in dual fuel mode has already been implemented on existent vessels, but the progressive decarbonization will lead to the utilization of carbon-neutral or carbon-free fuels such as, in the last case, hydrogen. Thanks to its high reactivity nature, it can be helpful in the reduction of exhaust CH4. On the contrary, together with the high temperatures achieved by its oxidation, hydrogen could cause uncontrolled ignition of the premixed charge and high emissions of NOx. As a matter of fact, a source of ignition is still necessary to have better control on the whole combustion development. To this end, an optimal and specific injection strategy can help to overcome all the before-mentioned issues. In this study, three-dimensional numerical simulations have been performed with the ANSYS Forte® software (version 19.2) in an 8.8 L dual fuel engine cylinder supplied with methane, hydrogen, or hydrogen–methane blends with reference to experimental tests from the literature. A new kinetic mechanism has been used for the description of diesel fuel surrogate oxidation with a set of reactions specifically addressed for the low temperatures together with the GRIMECH 3.0 for CH4 and H2. This kinetics scheme allowed for the adequate reproduction of the ignition timing for the various mixtures used. Preliminary calculations with a one-dimensional commercial code were performed to retrieve the initial conditions of CFD calculations in the cylinder. The used approach demonstrated to be quite a reliable tool to predict the performance of a marine engine working under dual fuel mode with hydrogen-based blends at medium load. As a result, the system modelling shows that using hydrogen as fuel in the engine can achieve the same performance as diesel/natural gas, but when hydrogen totally replaces methane, CO2 is decreased up to 54% at the expense of the increase of about 76% of NOx emissions.

Superior fuel economy, higher torque and durability have led to the diesel engine being widely used in a variety of fields of application, such as road transport, agricultural vehicles, earth moving machines and marine propulsion, as well as fixed installations for electrical power generation. However, diesel engines are plagued by high emissions of nitrogen oxides (NOx), particulate matter (PM) and carbon dioxide when conventional fuel is used. One possible solution is to use low-carbon gaseous fuel alongside diesel fuel by operating in a dual-fuel (DF) configuration, as this system provides a low implementation cost alternative for the improvement of combustion efficiency in the conventional diesel engine. An initial step in this direction involved the replacement of diesel fuel with natural gas. However, the consequent high levels of unburned hydrocarbons produced due to non-optimized engines led to a shift to carbon-free fuels, such as hydrogen. Hydrogen can be injected into the intake manifold, where it premixes with air, then the addition of a small amount of diesel fuel, auto-igniting easily, provides multiple ignition sources for the gas. To evaluate the efficiency and pollutant emissions in dual-fuel diesel-hydrogen combustion, a numerical CFD analysis was conducted and validated with the aid of experimental measurements on a research engine acquired at the test bench. The process of ignition of diesel fuel and flame propagation through a premixed air-hydrogen charge was represented the Autoignition-Induced Flame Propagation model included ANSYS-Forte software. Because of the inefficient operating conditions associated with the combustion, the methodology was significantly improved by evaluating the laminar flame speed as a function of pressure, temperature and equivalence ratio using Chemkin-Pro software. A numerical comparison was carried out among full hydrogen, full methane and different hydrogen-methane mixtures with the same energy input in each case. The use of full hydrogen was characterized by enhanced combustion, higher thermal efficiency and lower carbon emissions. However, the higher temperatures that occurred for hydrogen combustion led to higher NOx emissions.

Hydrogen-based technologies, prominently fuel cells, are emerging as strategic solutions for decarbonization. They offer an efficient and clean alternative to fossil fuels for electricity generation, making a tangible contribution to the European Green Deal climate objectives. The primary issue is the production and transportation of hydrogen. An on-site hydrogen production system that includes CO2 capture could be a viable solution. The proposed power system integrates an internal combustion engine (ICE) with a steam methane reformer (SMR) equipped with a CO2 capture and energy storage system to produce “blue hydrogen”. The hydrogen fuels a high-temperature polymer electrolyte membrane (HT-PEM) fuel cell. A battery pack, incorporated into the system, manages rapid fluctuations in electrical load, ensuring stability and continuity of supply and enabling the fuel cell to operate at a fixed point under nominal conditions. This hybrid system utilizes natural gas as its primary source, reducing climate-altering emissions and representing an efficient and sustainable solution. The simulation was conducted in two distinct environments: Thermoflex code for the integration of the engine, reformer, and CO2 capture system; and Matlab/Simulink for fuel cell and battery pack sizing and dynamic system behavior analysis in response to user-demanded load variations, with particular attention to energy flow management within the simulated electrical grid. The main results show an overall efficiency of the power system of 39.9% with a 33.5% reduction in CO2 emissions compared to traditional systems based solely on internal combustion engines.

We apply a novel approach for searching long transient gravitational wave signals in interferometric detector data, particularly those predicted from rapidly spinning newborn magnetars. We explored a machine-learning-based alternative to develop a fast algorithm for identifying signal candidates. We tested our method on real data collected during the third LIGO-Virgo-Kagra observing run. We demonstrate that our method is robust with respect to non-Gaussian noise and that, by combining the two interferometers, we can improve the search results.

The awareness of citizens concerning the health risks caused by environmental pollution is growing, but studies on determinants of pro-environmental behaviors have rarely examined health-related aspects. In this study, we investigated these determinants using data from a large survey among Italian university students (15 Universities: 4778 filled questionnaires). Besides the health-related aspects, represented by environmental health risk perception and functional health literacy, we considered social and demographic characteristics (gender, area of residence, sources of information, trust in institutional and non-institutional subjects, and students’ capacity of positive actions, indicated as internal locus of control). The attitudes towards pro-environmental behaviors were positive for more than 70% of students and positively related with health risk perception, internal locus of control, and health literacy. The correspondence between the positive attitudes towards pro-environmental behaviors and the real adoption of such behaviors was approximately 20% for most behaviors, except for the separate collection of waste (60%). Such a discrepancy can be attributable to external obstacles (i.e., lack of time, costs, lack of support). The health-related aspects were linked to the pro-environmental attitudes, but to a lesser extent to pro-environmental behaviors, owing to the complexity of their determinants. However, they should be taken in account in planning education interventions.

Sicca syndrome is a common condition that draws the attention of rheumatologists, and is frequently related to Sjögren’s disease (SjD). This study analyzed 164 patients with sicca syndrome (clinically suspected for SjD) who underwent minor salivary gland biopsy (mSGB). Patients completed the Xerostomia Inventory (XI) and Standard Patient Evaluation of Eye Dryness (SPEED) questionnaires to assess Patient-Reported Outcome Measures (PROMs), and biopsies were graded using the Chisholm and Mason system. Patients were classified as seropositive (SSA, SSB, Ro52, Ro60 positive) or seronegative, and also divided into three groups by age. Positive biopsies (60.37%) were more common in older patients (61–80) and associated with confirmed SjD, more severe xerostomia, and stronger lymphocytic infiltrates. Among these, 37.37% were seropositive, showing higher disease activity, hypergammaglobulinemia, and elevated IgG. Seronegative patients had a heavier symptom burden, confirmed by the PROMs, and more fibrosis and fatty replacement in biopsies. Age-stratified analysis showed younger patients (18–40) were more affected by ocular dryness, while older patients had worse xerostomia and more severe histological and ultrasound changes. Younger individuals had higher IgG/IgA, more anemia, and reduced C3. Hydroxychloroquine was used more in younger and seropositive groups; older patients used more topical therapies. These results highlight mSGB’s diagnostic value, especially in seronegative cases, and stress the importance of combining clinical, histological, imaging, and patient-reported outcomes for optimal care.

Nanocarriers are designed to specifically accumulate in diseased tissues. In this context, targeting of intracellular compartments was shown to enhance the efficacy of many drugs and to offer new and more effective therapeutic approaches. This is especially true for therapies based on biologicals that must be encapsulated to favor cell internalization, and to avoid intracellular endosomal sequestration and degradation of the payload. In this review, we discuss specific surface modifications designed to achieve cell cytoplasm delivery and to improve targeting of major organelles; we also discuss the therapeutic applications of these approaches. Last, we describe some integrated strategies designed to sequentially overcome the biological barriers that separate the site of administration from the cell cytoplasm, which is the drug's site of action.

High quality medical assistance and preventive strategies, including pursuing a healthy lifestyle, result in a progressively growing percentage of older people. The population and workforce is aging in all countries of the world. It is widely recognized that older individuals show an increased susceptibility to infections and a reduced response to vaccination suggesting that the aged immune system is less able to react and consequently protect the organism. The SARS-CoV-2 pandemic is dramatically showing us that the organism reacts to novel pathogens in an age-dependent manner. The decline of the immune system observed in aging remains unclear. We aimed to understand the role of B cells. We analyzed peripheral blood from children (4-18 years); young people (23-60 years) and elderly people (65-91 years) by flow cytometry. We also measured antibody secretion by ELISA following a T-independent stimulation. Here we show that the elderly have a significant reduction of CD27 dull memory B cells, a population that bridges innate and adaptive immune functions. In older people, memory B cells are mostly high specialized antigen-selected CD27 bright . Moreover, after in vitro stimulation with CpG, B cells from older individuals produced significantly fewer IgM and IgA antibodies compared to younger individuals. Aging is a complex process characterized by a functional decline in multiple physiological systems. The immune system of older people is well equipped to react to often encountered antigens but has a low ability to respond to new pathogens.

Anti-CD19 chimeric antigen receptor (CAR) T cell therapy has led to unprecedented responses in patients with high-risk hematologic malignancies. However, up to 60% of patients still experience disease relapse and up to 80% of patients experience CAR-mediated toxicities, such as cytokine release syndrome or immune effector cell-associated neurotoxicity syndrome. We investigated the role of the intestinal microbiome on these outcomes in a multicenter study of patients with B cell lymphoma and leukemia. We found in a retrospective cohort ( n  = 228) that exposure to antibiotics, in particular piperacillin/tazobactam, meropenem and imipenem/cilastatin (P-I-M), in the 4 weeks before therapy was associated with worse survival and increased neurotoxicity. In stool samples from a prospective cohort of CAR T cell recipients ( n  = 48), the fecal microbiome was altered at baseline compared to healthy controls. Stool sample profiling by 16S ribosomal RNA and metagenomic shotgun sequencing revealed that clinical outcomes were associated with differences in specific bacterial taxa and metabolic pathways. Through both untargeted and hypothesis-driven analysis of 16S sequencing data, we identified species within the class Clostridia that were associated with day 100 complete response. We concluded that changes in the intestinal microbiome are associated with clinical outcomes after anti-CD19 CAR T cell therapy in patients with B cell malignancies. In an analysis of adult patients with hematologic malignancies who received anti-CD19 chimeric antigen receptor T cell therapy, baseline gut microbiome composition was correlated with clinical response and treatment with broad-spectrum antibiotics in the four weeks prior to infusion was associated with worse survival and increased neurotoxicity.

Background Antimicrobial resistance in Enterobacterales represents a substantial threat in modern clinical practice and the collection of data on the efficacy of new molecules is of paramount importance. Our study aimed to analyse the in vitro activity of imipenem/cilastatin/relebactam (IMI/REL) against KPC-producing Klebsiella pneumoniae (KPC-Kp) and investigate the genetic determinants of resistance to this agent. Methods A total of 603 KPC-Kp strains, which were randomly collected during a multicentre study in northern Italy in the period 2016–2018, were analysed retrospectively. Antibiotic susceptibility testing was performed using a commercial broth microdilution. IMI-REL-resistant KPC-Kp strains were further analysed by whole genome sequencing to identify resistance determinants. Results Ninety-eight percent of KPC-Kp (591/603) showed in vitro susceptibility to IMI/REL, with a minimum inhibitory concentration below the EUCAST cut-off. Different mutations in OmpK36 were found in all 12 IMI/REL-resistant strains, which belonged to MLST STs 258 (3 isolates), 307 (8 isolates) and 512 (1 isolate), but no clonal relatedness was detected by the minimum spanning tree analysis, except for 2 strains isolated in the same hospital. Equal distribution of bla KPC−2 (6/12) and bla KPC−3 (6/12) was found, and in 11 isolates the presence of genetic variants associated with the production of beta-lactamases was also identified. KPC-Kp resistant to IMI/REL retained susceptibility to meropenem/vaborbactam (MVB, 12/12, 100%) and ceftazidime/avibactam (CZA, 11/12, 91.7%). Only one strain of 603 was resistant to either MVB and CZA but susceptible to IMI/REL with a MIC of 2 mg/L; 4/603 (0.7%) were resistant to CZA but susceptible to IMI/REL and MVB. Conclusions IMI/REL showed good in vitro activity against the KPC-Kp strains analysed. All the IMI/REL-resistant strains displayed a mutation in porin OmpK36 and produced carbapenemases, with KPC-2 and KPC-3 being equally distributed. MVB and CZA maintained good activity against IMI/REL resistant isolates.