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Raman spectroscopy was applied on nanostructured ZnFe2O4 system in order to correlate its structural, chemical, and vibrational properties to the functional behaviour, in view of the high sensitivity of the Raman probe to the cationic order in iron oxides. In particular we investigated pure and Ga/Mg doped zinc ferrite nanoparticles synthesised by co-precipitation route by means of Raman spectroscopy with a particular focus on the correlation between their structural and magnetic properties. We firstly studied the homogeneity of the samples at the micrometer scale and their stability under laser irradiation disregarding the presence of spurious iron oxides in favour of a highly defective external shell of the nanoparticles. This hypothesis was corroborated by varying the incident laser wavelength therefore changing the investigated volume. Furthermore, we estimated the inversion degree of the spinel structure finding good agreements with the trend of the magnetic features. All the evidence found through Raman spectroscopy are supported by the results obtained with X-Ray Powder Diffraction, Electron Paramagnetic Resonance and SQUID magnetometry.

Background Heart failure with preserved ejection fraction (HFpEF) diagnosis remains challenging, since several mechanisms (diastolic and systolic reserve abnormalities, chronotropic incompetence, ventricular or vascular stiffening, atrial dysfunction, pulmonary hypertension, impaired vasodilation, endothelial dysfunction, energetic abnormalities and autonomic dysfunction) play different roles in HFpEF development. European Society of Cardiology HF guidelines recently suggested a stepwise non-invasive diagnostic approach consisting of three steps: the first is clinical, the second includes echocardiographic and laboratory data (natriuretic peptides), named HFA-PEEF score, and finally, in case of inconclusive findings, diastolic stress echocardiography is recommended. On the other hand, in United States, another multiparametric score, named H2FPEF, has been proposed for HFpEF diagnosis, and including, in addition to echocardiographic parameters, also clinical data; thereby more applicable in the outpatient clinical arena. Purpose Whether there is a clinical overlap between the two scores (HFA-PEEF and H2FPEF) as well as whether the addition of clinical data to the HFA-PEEF could improve its ability to identify different HFpEF phenotypes is still an open issue and these were the aims of our study. Methods HFA-PEEF and H2FPEF scores were systematically applied on 1,156 consecutive subjects with preserved ejection fraction who undergone cardiovascular evaluation at the Cardiovascular Prevention Center of Fondazione Don Gnocchi & University of Parma. All subjects underwent cardiovascular risk assessment followed by echocardiography and cardiopulmonary exercise testing; due to the outpatient (non-acute) setting of the evaluation, natriuretic peptides assay was not performed. Clinical data and cardiovascular risk factors data were compared between different groups of HFpEF risk. Results According to H2FPEF score, low risk (75%) in 197 (17%); according to HFA-PEEF score, 675 (58%) had 0 or 1 point, 253 (22%) had 2 points and 230 (20%) had 3 or 4 points (moderate-to-high risk). Patients with higher HFA-PEEF score were older (p75 years to a 4.6-fold higher risk, HTN to a 3.6-fold higher risk (p Conclusions Although HFA-PEEF score does not include clinical data, patients with older age, atrial fibrillation, hypertension, hypertensive heart, diabetes, sedentary lifestyle and chronic coronary syndrome show a higher ESC risk of HFpEF. Funding Acknowledgement Type of funding sources: None.

Background Exercise intolerance evaluation in Heart failure with preserved ejection fraction (HFpEF) remains challenging, since several mechanisms (diastolic and systolic reserve abnormalities, low chronotropic reserve (CR), ventricular or vascular stiffening, atrial dysfunction, pulmonary hypertension, endothelial dysfunction, energetic abnormalities and autonomic dysfunction) play different roles. European Society of Cardiology HF guidelines recently suggested a stepwise non-invasive HFpEF diagnostic approach consisting of three steps: clinical, echocardiographic and laboratory data (natriuretic peptides), named HFA-PEEF Score, and finally, in case of inconclusive findings, diastolic stress echocardiography data. Cardiopulmonary exercise testing (CPET) may represent a promising further non-invasive diagnostic tool in HFpEF evaluation since allow to assess the presence of reduced functional capacity as well as to differentiate between cardiovascular, ventilatory or peripheral causes. Purpose Whether increased risk of HFpEF is associated with different and specific cardiopulmonary responses to exercise is still an open issue and this was the aim of our study. Methods 1.156 consecutive subjects with preserved ejection fraction undergoing cardiovascular evaluation at the Cardiovascular Prevention Center of Fondazione Don Gnocchi & University of Parma were enrolled. All subjects underwent cardiovascular evaluation and echocardiography, HFA-PEEF and H2FPEF Score assessment and cardiopulmonary exercise testing. Different cardiopulmonary response to exercise were compared between different groups of HFpEF risk. Results According to HFA-PEEF Score, 675 (58%) had 0 or 1 point, 253 (22%) had 2 points and 230 (20%) had 3 or 4 points (moderate-to-high risk). Patients with both higher HFA-PEEF and H2FPEF Score showed lower functional capacity, expressed as low peak V02 (p35) to a 2.4-fold higher risk (p Conclusions Different degrees HFpEF risk, estimated using both HFA-PEEF and H2FPEF score, are associated with different cardiopulmonary responses to exercise. High HFpEF risk patients show low functional capacity, cardiovascular and ventilator efficiency due to lower cardiac output at peak, despite preserved ejection fraction, associated to lower chronotropic response to exercise. Funding Acknowledgement Type of funding sources: None.

Introduction/Background* Personalized medicine is replacing the classical one-size-fits-all traditional oncology approaches tailoring the most appropriate therapy for each patient. Molecular and genomic profiling diagnostic tools are implementing patients’ journey. Methodology This is a single centre prospective study performed from January 2020 and April 2021 at Fondazione IRCCS Istituto Nazionale dei Tumori di Milano (Italy). All consecutive, heavily pretreated patients, for whom effective conventional treatments were not available, were enrolled in this study and underwent molecular and genomic profiling via Foundation One CDx test. Result(s)* Overall, 63 heavily pretreated patients had Foundation One CDx test. We identified 10 patients (16%) with mutation or genetic signatures candidate to use personalized therapy (table 1). Out of 10 patients, 4 are patients affected by cervical, 4 by endometrial and the remnant are affected by ovarian carcinoma. Actually 1 patient is receiving immunotherapy with atezolizumab plus anti-ICOS and 1 is undergoing evaluation in order to start same drugs; 2 patients with ovarian cancer had BRAF/V600E mutations and are ongoing on treatment with trametinib +/- dabrafenib; 2 patients with cervical cancer had PI3KCA mutations and are treating with alpelisib. Furthermore, in 4 patients an actionable mutation was found but standard chemotherapeutic treatment is still ongoing (table 2). Immunotherapy and target therapy are administered into the clinical trial or thank to compassionate use. Conclusion* Molecular and genomic profiling of gynecological malignancies is not clinical practice. We demonstrated that in this population identified alterations, by genetic driver, could help to find a new therapeutically opportunity. This allows to identify predictive biomarkers for target therapies in order to offer new therapeutic prospective for our gynecologic patients.

Introduction/Background* Advanced/recurrent cervical cancer has limited therapeutic options, with a median progression-free survival (PFS) after the failure of systemic treatments ranging between 3.5 and 4.5 months. Here, we reported our preliminary experience in the use of BYL719 (alpelisib) in advanced/recurrent cervical cancer after failure of at least 2 lines of treatment. Methodology The Fondazione IRCCS Istituto Nazionale dei Tumori di Milano (Italy) approved this prospective investigation. From 04/01/2020 to 09/01/2020, 17 consecutive patients with recurrent cervical cancer underwent next generation sequencing (NGS) to assess the presence of PIK3CA mutation/alteration. Result(s)* Overall, 17 patients were tested for PIK3CA mutation/alteration. PIK3CA mutation was detected in seven (41%) patients. Six patients were included in the study; one patient was diagnosed with a synchronous tumor during the screening phase. All patients had been treated with at least 2 previous lines of systemic treatment: 3 patients received >2 prior lines of treatment in the recurrent or metastatic setting; 60% had received prior bevacizumab in combination with chemotherapy. All patients started alpelisib at the daily dosage of 300 mg. Investigator-assessed confirmed objective response rate (ORR) was 33%. The disease control rate (DCR) was 100%. According to the RECIST 1.1, two patients had a partial response (PR), and four patients had stable disease (SD). No complete response was observed. The mean duration of response (DOR) was 6.6 (SD 3.75) months; four patients had PR lasting for >6 months. One patient stopped the treatment at 0.82 months due to the onset of a grade 2 adverse event (AE) (skin rash). Grade 3 treatment-related AEs included: lymphoedema (n=1, 20%) and rash (n=1, 20%). No treatment-related grade 4–5 AEs occurred. Conclusion* Further trials are needed to assess the safety and effectiveness of alpelisib in PIK3CA-mutated recurrent/advanced cervical cancer

Local communities and individual species jointly contribute to the overall beta diversity in metacommunities. However, it is mostly unknown whether the local contribution (LCBD) and the species contribution (SCBD) to beta diversity can be predicted by local and regional environmental characteristics and by species traits and taxonomic relatedness, respectively. We investigated the LCBD and SCBD of stream benthic diatoms and insects along a gradient of land use intensification, ranging from streams in pristine forests to agricultural catchments in southeast subtropical Brazil. We expected that the LCBD would be negatively related to forest cover and positively related to the most unique streams in terms of environmental characteristics and land use (hereafter environmental and land use uniqueness, respectively). We also expected that species with a high SCBD would occur at sites with reduced forest cover. We found that the LCBD of diatoms and insects was negatively related to forest cover. The LCBD of insects was also positively related to environmental and land use uniqueness. As forest cover was negatively related to uniqueness in land use, biologically unique streams were those that deviated from the typical regional land cover. We also found that diatom traits, insect traits, and taxonomic relatedness partly explained SCBD. Furthermore, the SCBD of diatoms was positively correlated with forest cover, but the inverse was found for insects. We showed that deforestation creates novel and unique communities in subtropical streams and that species that contribute the most to beta diversity can occur at opposite ends of a land use gradient.

Left atrial (LA) speckle tracking echocardiography (STE) provides indices of LA deformation such as strain and strain rate. These variables offer useful clinical information in human and canine patients with cardiac disease. At present, reference ranges for LA STE variables in dogs are scarcely established and, due to variability among centers, they cannot be accepted worldwide. The present study aimed to provide normal ranges for LA strain and strain rate variables in clinically healthy dogs, and to evaluate the effect of clinical parameters such as bodyweight. Eighty clinically healthy dogs served as the study population. Left atrial STE was feasible in all dogs and agreement within and between observers was clinically acceptable for most of the variables, in particular strain variables. Age, sex, and heart rate did not affect LA STE. Bodyweight was negatively correlated with strain variables and positively correlated with diastolic strain rate variables and the relationship was allometric. Bodyweight-based vendor-dependent prediction intervals for LA STE variables in clinically healthy dogs could aid the evaluation of LA function in clinical practice.

Background Even thought lifestyle changes have a main role in cardiovascular disease prevention, people show a weak adherence to medical advices. Aim of our study was to identify anamnestic predictors of poor compliance for lifestyle changes in a general population. Methods We submitted a 26 questions questionnaire to 301 general population subjects, investigating multiple anamnestic characteristics. Afterwards, we proceeded to explain people the main line of the European society of Cardiology guidelines on Cardiovascular prevention. Finally, we asked the subjects if this prevention campaign was able to modify their lifestyle. Results Sixty-four percent of interviewed were prone to change their lifestyle. Females answered positively more than males (73% vs 59%, p = 0.011). In terms of cardiovascular risk factors only the presence of dyslipidemia was significantly associated with a will of change (84% vs 58%, p = 0.000). Age (49 (18) vs 46 (20) ), familiar history of cardiovascular disease (69% vs 63%,p=0.320) and the presence of a previous cardiovascular event (68% vs 66%,p=0.841), do not predict the adherence to lifestyle change. Key messages Cardiovascular disease dose not influence people’s decision in life style change. Male gender represents an anamnestic characteristics that predict a poor adherence to lifestyle changes while people affected by dyslipidemia more frequently are prone to modify their routine.

Ecological drift can override the effects of deterministic niche selection on small populations and drive the assembly of small communities. We tested the hypothesis that smaller local communities are more dissimilar among each other because of ecological drift than larger communities, which are mainly structured by niche selection. We used a unique, comprehensive dataset on insect communities sampled identically in a total of 200 streams in climatically different regions (Brazil and Finland) that differ in community size by fivefold. Null models allowed us to estimate the magnitude to which beta diversity deviates from the expectation under a random assembly process while taking differences in species richness and relative abundance into account, i.e., beta deviation. Beta diversity of small tropical communities was consistently higher but closer to null expectations than β-diversity of large communities. However, although β-deviation and community size were strongly related in both regions, the direction of the relationship varied according to dissimilarity metrics. While incidence-based β-diversity was lower than expected (communities were less dissimilar than null expectations) and negatively related to community size in Brazil, abundance-based β-diversity was higher than expected (communities were more dissimilar than null expectations) and positively related to community size in both regions. We suggest that ecological drift drives variation in small communities by increasing the chances of species with low abundance and narrow distribution to occur within the metacommunity. Also, while weak niche selection and high dispersal rates likely reduced variation in community structure among large tropical streams, niche selection was likely sufficient to cause non-random variations in the relative abundances of genera among large communities in both regions. Habitat destruction, overexploitation, pollution, and reductions in connectivity have been reducing the size of biological communities. These environmental pressures will make smaller communities more vulnerable to novel conditions and render community dynamics more unpredictable, as random demographic processes should prevail under these conditions. Incorporation of community size into ecological models should provide conceptual, empirical and applied insights into a better understanding of the processes driving changes in biodiversity.

Background there is little solid evidence of the effectiveness of psychological interventions using MBRS program for those with advanced cancer. The objective of this study was to evaluate the acceptability and potential benefits of MBSR for pt with cancer pain in early palliative care. Methods Main inclusion criteria were: advanced cancer pt in early palliative care; NRS >3;PS >60% according to Karnosky, informed consent. 20 advanced cancer pt were enrolled. Each session included different forms of mindfulness meditation practice, mindful awareness during yoga postures and mindfulness during stressful situations. Participants enter upon enrolling into a commitment to carry out daily 45-min homework assignments .A dedicate nurse with experience in palliative care attended each mindfulness session. Primary outcome was total pain at the end of MBSR intervention evaluated by both VAS and ESAS scales. Secondary outcome was mood state change evaluated by POMS questionnaire. Satisfaction of treatment and compliance were also evaluated. All questionnaires along with a form for collecting personal and clinical data were administered by nurse at baseline and at the end of MBSR intervention. Results 19 out of 20 were female with median age 54 years old. 56% were receiving morphine for cancer pain. Preliminary results did show slight reduction in total pain score which however was not statistically significant. The POMS test showed significant changes in the mean scores indicating a statistically significant improvement of mood at the end of mindfulness sessions. Compliance program and homework was 70% while pt satisfaction was 78%. Conclusions This program appears to be feasible and well accepted. The improvements in the mood state suggests that the mindfulness techniques could play a role in helping patients to reduce mood disturbance. The role of nurse was optimal to allow critically ill patients to participate in MBRS and to guarantee adherence and satisfaction. Moreover nurse was very helful to support the mindfulness trainer in managing cancer patients according to their physical needs. Finally the presence of nurse has been evaluated by patients as part of cancer caring. Legal entity responsible for the study Fabrizio Artioli. Funding Has not received any funding. Disclosure All authors have declared no conflicts of interest.

The responses of native plants to competition with invasive plants depend mainly on the density of the invasive plants and on the ability of the native plants to compete for resources. In this study, we tested the influence of the invasive exotic Urochloa arrecta (Poaceae) on the early colonization of two native species (Pontederia cordata and Leersia hexandra) of aquatic macrophytes. Our hypotheses were (i) the competitive effects of U. arrecta on the native species P. cordata and L. hexandra are density-dependent and that (ii) these species respond differently to competitive interactions with the invasive species. We conducted the experiments in a greenhouse and in the field, in a tropical reservoir. The biomass of U. arrecta (ranging from 206.2 to 447.1 g) was manipulated in the greenhouse in trays with different densities. After the establishment of the invasive species, we added P. cordata and L. hexandra propagules to each tray. In the field, a propagule of P. cordata was planted in 36 sites with different densities of U. arrecta. The biomass and length of the natives and the biomass of the invasive species were measured in the greenhouse and in the field experiments. The biomass and length of the native plants decreased with increasing biomass of the exotic species in both experiments, showing that the competition between U. arrecta and native species depends on the density of the exotic species. The root:shoot ratio of L. hexandra decreased with increasing U. arrecta biomass, but the opposite occurred for P. cordata. These results indicate that native species exhibit different strategies of biomass allocation when interacting with U. arrecta. The strong competitive effects of U. arrecta and the different responses of the native species help to explain the reduced diversity of native macrophytes observed in sites colonized by U. arrecta. The results also suggest that in a scenario of dominance of exotic species, recolonization by native macrophytes is unlike to occur naturally and without human interventions that reduce the biomass of the exotic species.

This work was performed within the framework of the Working Group (WG) “Coastal Morphodynamics” of the Italian Association of Physical Geography and Geomorphology (AIGeo), in the wider context of AIGeo cooperation with the Institute for the Protection and Environmental Research (ISPRA) for the updating of the legend for the “Geomorphological Map of Italy”. The WG dealt with the legend for the coastal portions and focused on marine, lagoon, lacustrine, and eolian landforms, processes and deposits. The legend specifically addresses the coastal zoning of geomorphological hazard and risk in order to support land-use planning and management. The proposed legend seeks to represent and highlight the origin of each landform as well as their dynamics and modern trends. The legend provides information about morphological characteristics at small and large scales. The relict morphological features and the active ones are reported together with the quantitative parameters useful for the description of the present morphodynamics and wave/climate conditions. On the basis of the activities and experiences carried out by the “Coastal Morphodynamics” AIGeo WG, during the last year, some examples of coastal geomorphological mapping at different scale (1:5.000 and 1:25.000) are presented. They concentrate on the problems both of the littoral plain and rocky coast dynamics and to the interactions with anthropic modifications.

Una consistente campagna di acquisizione di dati di sottosuolo (18 carotaggi con profondità da 7 a 15 m) condotta con approccio interdisciplinare, finalizzato a una rappresentazione integrata del log stratigrafico, ha permesso di incrementare in modo significativo le conoscenze del contesto paleoambientale ed insediativo della zona urbana e suburbana della città di Pisa durante gli ultimi 6000 anni circa e di valutare il reciproco condizionamento fra l’ambiente naturale e le caratteristiche dell’insediamento umano/In the urban and periurban area of Pisa, 18 cores ranging in depth between 7 and 15 m were performed and analysed through an interdisciplinary approach, which led to an improved stratigraphic log representation. In the urban and periurban area of Pisa, 18 cores ranging in depth between 7 and 15 m were performed and analysed through an interdisciplinary approach, which led to an improved stratigraphic log representation.

Dopo aver definito l’area oggetto di indagine, si passano in rassegna i metodi utilizzati per l’acquisizione di nuovi dati. Gli archeologi si confrontano con i problemi degli archivi e dello stato della documentazione; i sedimentologi individuano le aree per la realizzazione di sondaggi a carotaggio continuo, mentre i geomorfologi riconoscono nell’analisi del microrilievo, nella fotointerpretazione e nel telerilevamento la base delle loro analisi. I matematici descrivono infine il modello page rank classico, adattato al problema della determinazione del potenziale archeologico/After defining the area of investigation, the methods used for acquiring new data will be described. The archaeologists will address the problems encountered with the archives and the status of documentation, the sedimentologists will identify the areas for continuous coring, whilst the geomorphologists will base their analyses on micro-relief, photointerpretation and remote sensing techniques. Finally, the mathematicians will describe the classic page rank model, adapted to the determination of archaeological potential.

Multiple alpha coincidence and correlations are studied in the reaction $^{12}$C+$^{12}$C at 95 MeV for fusion-evaporation events completely detected in charge. Two specific channels with Carbon and Oxygen residues in coincidence with $\alpha$-particles are addressed, which are associated with anomalously high branching ratios with respect the predictions by Hauser-Feshbach calculations. Triple alpha emission appears kinematically compatible with a sequential emission from a highly excited Mg. The phase space distribution of $\alpha$-$\alpha$ coincidences suggests a correlated emission from a Mg compound, leaving an Oxygen residue excited above the threshold for neutron decay. These observations indicate a preferential $\alpha$ emission of $^{24}$Mg at excitation energies well above the threshold for $6-\alpha$ decay., Comment: 21 pages, 17 figures, second paper of a series of two

A new measurement of the dynamical dipole emission was performed in the system O-16 + Sn-116 at 12 MeV/nucleon. These data, together with those measured at 8.1 MeV/nucleon and 15.6 MeV/nucleon on the same system, provide the dependence of the dynamical dipole total emission yield on the beam energy. The energy removed by preequilibrium charged particles emission was directly measured and this made possible the direct estimation of the compound nucleus excitation energy. The experimental results show a weak increase of the dynamical dipole total yield with beam energy and they are in agreement both in trend and in absolute values with the predictions of the theoretical model based on the Boltzmann-Nordheim-Vlasov approach. The measured gamma-ray angular distribution has a dipole character but with a strong quenching probably owing to the rotation of the dipolar axis during the fusion and thermalization processes.

The $^{12}$C+$^{12}$C reaction at 95 MeV has been studied through the complete charge identification of its products by means of the GARFIELD+RCo experimental set-up at INFN Laboratori Nazionali di Legnaro (LNL). In this paper, the first of a series of two, a comparison to a dedicated Hauser-Feshbach calculation allows to select a set of dissipative events which corresponds, to a large extent, to the statistical evaporation of highly excited $^{24}$Mg. Information on the isotopic distribution of the evaporation residues in coincidence with their complete evaporation chain is also extracted. The set of data puts strong constraints on the behaviour of the level density of light nuclei above the threshold for particle emission. In particular, a fast increase of the level density parameter with excitation energy is supported by the data. Residual deviations from a statistical behaviour are seen in two specific channels, and tentatively associated with a contamination from direct reactions and/or $\alpha$-clustering effects. These channels are studied in further details in the second paper of the series., Comment: 24 pages, 15 figures, first paper of a series of two

Controversial data exist about the long-term results of aortic coarctation (AC) repair. This study explored the prevalence and predictors of left ventricular (LV) hypertrophy, late hypertension, and hypertensive response to exercise in 48 subjects (age, 15.1 ± 9.7 years) currently followed in the authors' tertiary care hospital after successful AC repair. Data on medical history, clinical examination, rest and exercise echocardiography, and ambulatory blood pressure monitoring were collected. The time from AC repair to follow-up evaluation was 12.9 ± 9.2 years. The prevalence of LV hypertrophy ranged from 23 to 38 %, based on the criteria used to identify LV hypertrophy, and that of concentric geometry was 17 %. One sixth of the patients without residual hypertension experienced late-onset hypertension. One fourth of those who remained normotensive without medication showed a hypertensive response to exercise. Age at AC repair was the strongest independent predictor of LV hypertrophy, defined using indexation either for body surface area (odds ratio [OR], 1.03; p = 0.0090) or for height(2.7) (OR 1.02; p = 0.029), and it was the only predictor of late hypertension (OR 1.06; p = 0.0023) and hypertensive response to exercise (OR 1.09; p = 0.029). The risk of LV hypertrophy was 25 % for repair at the age of 3.4 years but rose to 50 and 75 % for repair at the ages of 5.9 and 8.4 years, respectively. Similar increases were found for the risk of late-onset hypertension and hypertensive response to exercise. A considerable risk of LV hypertrophy, late hypertension, and hypertensive response to exercise exists after successful AC repair. Older age at intervention is the most important predictor of these complications.

Reynolds-averaged Navier–Stokes (RANS) modelling and large eddy simulation (LES) of a plane air jet impinging orthogonally on a flat surface is described. Comparisons of predictions are made with the data of Yoshida et al. for a Re = 10,000 flow, with good agreement found in both the free and wall jet regions. Some under-prediction, particularly by the RANS approach, of turbulence quantities is apparent, and overall the LES is clearly in closer agreement with data, particularly in zones where large turbulence structures dominate. Differences in LES and RANS for the particular flow considered are not large, however, and this may be attributed to the significant effort already expended in the development of second-moment turbulence closures with wall reflection effects for impinging flow application. The results presented go some way towards validating LES for application to impinging flows, although uncertainties in the data set used for comparison purposes demonstrate a requirement for further experimental work.

The LES-Lagrangian particle methodology is applied to the study of vaporizing particle laden flows. A probabilistic description of the liquid phase is adopted and stochastic models for the filtered Lagrangian rates of change of droplet mass and temperature of the spray are presented. The method is applied to an acetone spray which issues into an air co-flow to form an evaporating droplet laden jet. Comparisons of the LES results with measurements demonstrate that the essential features of the flow are reproduced to a good accuracy.

A large-eddy-based methodology for the simulation of turbulent sprays is discussed. The transport equations for the spatially filtered gas phase variables, in which source terms accounting for the droplet effects are added, are solved together with a probabilistic description of the liquid phase. The probabilistic approach for the liquid phase is based on the transport equation for the spatially filtered joint probability density function of the variables required in order to describe the state of the liquid phase. In this equation, unclosed terms representing the filtered Lagrangian rates of change of the variables describing the spray are present. General modelling ideas for subgrid-scale (SGS) effects are proposed. The capabilities of the approach and the validity of the closure models, with particular with respect to the SGS dispersion, are investigated through application to a dilute particle-laden turbulent mixing layer. It is demonstrated that the formulation is able to reproduce very closely the measured properties of both the continuous and dispersed phases. The large-eddy simulation (LES) results are also found to be entirely consistent with the experimentally observed characteristics of droplet–gas turbulence interactions. Consistent with direct numerical simulation (DNS) studies of isotropic turbulence laden with particles where the entire turbulence spectrum is found to be modulated by the presence of particles, the present investigation, which comprises the effects of particle transport upon the large-scale vortical structures of a turbulent shear flow, highlights what appears to be a selective behaviour; few large-scale frequencies gain energy whereas the remaining modes are damped.