Composition Of Clusters Research Articles

Strain‐Induced Structural Rearrangement Towards a White‐Light‐Emitting Adamantane‐Type Cluster Dimer

AbstractGroup 14/16 adamantane‐type hybrid clusters of the type [(RT)4E6] (T=group 14 element, E=group 16 element, R=organic group) have been reported to emit white‐light when irradiated in an amorphous state with a continuous‐wave (CW) infrared laser diode. This effect is enhanced if the cluster core is varied from a binary to a more complex composition. To further explore this phenomenon, we synthesized clusters with a multinary R/R’‐T/T’‐E/E’ composition, including isolobal replacement of E with CH2, in [(2‐NpSi){CH2Sn(S)Ph}3] (1, Np=naphthyl). When expanding one of the CH2 moieties to a C2H4 group, thus generating a R/R’‐T/T’‐E/E’/E’’ cluster composition, we unexpectedly observed a dimerization of the initially formed, yet non‐isolable adamantane‐like cluster [(2‐NpSi){CH2Sn(S)Ph}2{C2H4Sn(S)Ph}] (2) to [(2‐NpSi){CH2Sn(S)Ph}2{C2H4Sn(S)Ph}]2 (3), exhibiting a heretofore unprecedented cluster architecture. Both monomeric 1 and dimeric 3, show white‐light emission as thin films. The nonlinear optical response of the compounds was also modelled with DFT methods.

0D/1D p-n heterostructured composite of bismuth ferrite perovskite clusters on sodium titanate nanotube arouse exceptional blue-light-driven photooxidation

This study describes the synthesis of a 0D/1D p-n heterostructured composite of bismuth ferrite perovskite clusters on sodium titanate nanotubes prepared using an in-situ hydrothermal method. BiFeO3/Na2Ti3O7 (BFT) nanocomposite, forming a p-n heterojunction due to the equilibrium of Fermi level, exhibits exceptional blue-light-driven photo-oxidation activity with an exceptional benzyl alcohol conversion rate of 29.64 mmolproduced BAD·g−1 h−1. The outstanding performance originates from the promotion of photogenerated charge separation and effective inhibition of charge recombination due to internal electric field of p-n heterojunction. Density functional theory calculations combined with femtosecond transient absorption spectroscopy distinctly confirms the efficient separation and transfer of photogenerated carriers to be S-scheme charge transfer mechanism over the p-n heterojunctions. Furthermore, in-situ infrared spectroscopy combined with XPS results demonstrate the strong adsorption of benzyl alcohol and weak adsorption of benzaldehyde on BFT, which facilitates the transformation of reactant and desorption of product. This study provides a simple and effective approach to enhance photocatalytic selective oxidation reactions.

Geometric structures and adsorption energies of mixed methanol and C60 cationic clusters produced within helium nanodroplets

Mass spectrometry is a useful technique for studying molecular cluster sizes, their distributions, compositions, and stability. Methanol and fullerenes are among the species identified in the interstellar medium and, due to their high abundance, their interactions are an interesting investigation topic. A mass spectrometric study of mixed clusters of methanol and C60 inside helium nanodroplets is presented. Anomalies in the distribution intensities or magic numbers were observed for [CH3OH]4[C60]m+,1≤m≤7. Water molecules within clusters were also detected, arising as one of the products of intermolecular methanol dehydration. Optimized and supposedly stable geometrical structures of these molecules are presented along with corresponding HOMO–LUMO gaps and adsorption energies. A linear decrease in adsorption energy and saturation at a critical cluster size was noticed.

Multivariate genetic analysis and diversity assessment in lotus (Nelumbo nucifera) accessions

The present study was carried out during 2019 to 2022 at the Floriculture Research Station (Tamil Nadu Agricultural University, Coimbatore, Tamil Nadu), Thovalai, Kanyakumari, Tamil Nadu to access the genetic variability in lotus accessions (Nelumbo nucifera) collected from 6 diverse locations. The research presents significant insights into the growth and flowering characteristics of these extraordinary aquatic plants and their adaptability to various environmental conditions. The analysis of mean performance showcases noteworthy variations in plant height, leaf dimensions, flowering time and the number of leaves, and flowers/plant across different collection sites, highlighting the profound influence of local environmental conditions on lotus growth. Lotus traits with significant genetic diversity and heritability, presenting opportunities for targeted selective breeding were identified. Principal component analysis uncovers key trait influencers, while cluster analysis categorizes accessions based on similarities, streamlining research and cultivation. Correlation and path analysis unveil relationships among lotus traits, enhancing our understanding of growth factors. D2 cluster composition reveals distinct groupings; Cluster I includes KNn1 and KNn5, Cluster II features KNn2, Cluster III comprises KNn6, Cluster IV contains KNn3, and Cluster V houses KNn4. Genetic divergence analysis identifies the number of flowers/plant as the primary driver of genetic diversity, emphasizing its importance for breeding. It underscores the need to consider both genetic and environmental factors in lotus cultivation and highlights the importance of targeted breeding efforts to unlock the full potential of lotus.

Application of the Decision Tree Method for Differentiating Human Groups

One of the tasks of modern biological anthropology is to develop a system that could objectively classify humanity on the basis of measurements. Here, the decision tree algorithm was chosen to create a classification of groups. The method helps to evaluate the differentiating power of specific dimensions for separating samples and to assess the composition of clusters at each step of the analysis. Standard cranial measurements were used, and the entropy index was chosen as a heterogeneity measure. Classification units were 39 ethno-territorial groups from 13 major regions of the Old World. At the first step, differentiation is made between broad-faced and narrow-faced groups, demonstrating the classificatory value of this trait. The first cluster includes only Mongoloids, admixed Southern Siberian populations, and Ainu. The second cluster is heterogeneous, but its further subdivision is more in line with the traditional classification. Traits underlying the branching of the tree may be the same in different branches, evidencing their taxonomic importance. Capabilities of the decision tree method proved sufficient to construct a system largely similar to the traditional one. Certain traits separate large groups of populations, while others are efficient at the regional level. The method, therefore, can be recommended as a supplementary tool at the intraspecific level.

Strain-Induced Structural Rearrangement Towards a White-Light-Emitting Adamantane-Type Cluster Dimer.

Group 14/16 adamantane-type hybrid clusters of the type [(RT)4E6] (T=group 14 element, E=group 16 element, R=organic group) have been reported to emit white-light when irradiated in an amorphous state with a continuous-wave (CW) infrared laser diode. This effect is enhanced if the cluster core is varied from a binary to a more complex composition. To further explore this phenomenon, we synthesized clusters with a multinary R/R'-T/T'-E/E' composition, including isolobal replacement of E with CH2, in [(2-NpSi){CH2Sn(S)Ph}3] (1, Np=naphthyl). When expanding one of the CH2 moieties to a C2H4 group, thus generating a R/R'-T/T'-E/E'/E'' cluster composition, we unexpectedly observed a dimerization of the initially formed, yet non-isolable adamantane-like cluster [(2-NpSi){CH2Sn(S)Ph}2{C2H4Sn(S)Ph}] (2) to [(2-NpSi){CH2Sn(S)Ph}2{C2H4Sn(S)Ph}]2 (3), exhibiting a heretofore unprecedented cluster architecture. Both monomeric 1 and dimeric 3, show white-light emission as thin films. The nonlinear optical response of the compounds was also modelled with DFT methods.

Impact of MRI radiomic feature normalization for prognostic modelling in uterine endometrial and cervical cancers

Widespread clinical use of MRI radiomic tumor profiling for prognostication and treatment planning in cancers faces major obstacles due to limitations in standardization of radiomic features. The purpose of the current work was to assess the impact of different MRI scanning- and normalization protocols for the statistical analyses of tumor radiomic data in two patient cohorts with uterine endometrial-(EC) (n = 136) and cervical (CC) (n = 132) cancer. 1.5 T and 3 T, T1-weighted MRI 2 min post-contrast injection, T2-weighted turbo spin echo imaging, and diffusion-weighted imaging were acquired. Radiomic features were extracted from within manually segmented tumors in 3D and normalized either using z-score normalization or a linear regression model (LRM) accounting for linear dependencies with MRI acquisition parameters. Patients were clustered into two groups based on radiomic profile. Impact of MRI scanning parameters on cluster composition and prognostication were analyzed using Kruskal–Wallis tests, Kaplan–Meier plots, log-rank test, random survival forests and LASSO Cox regression with time-dependent area under curve (tdAUC) (α = 0.05). A large proportion of the radiomic features was statistically associated with MRI scanning protocol in both cohorts (EC: 162/385 [42%]; CC: 180/292 [62%]). A substantial number of EC (49/136 [36%]) and CC (50/132 [38%]) patients changed cluster when clustering was performed after z-score-versus LRM normalization. Prognostic modeling based on cluster groups yielded similar outputs for the two normalization methods in the EC/CC cohorts (log-rank test; z-score: p = 0.02/0.33; LRM: p = 0.01/0.45). Mean tdAUC for prognostic modeling of disease-specific survival (DSS) by the radiomic features in EC/CC was similar for the two normalization methods (random survival forests; z-score: mean tdAUC = 0.77/0.78; LRM: mean tdAUC = 0.80/0.75; LASSO Cox; z-score: mean tdAUC = 0.64/0.76; LRM: mean tdAUC = 0.76/0.75). Severe biases in tumor radiomics data due to MRI scanning parameters exist. Z-score normalization does not eliminate these biases, whereas LRM normalization effectively does. Still, radiomic cluster groups after z-score- and LRM normalization were similarly associated with DSS in EC and CC patients.

Innovative two-dimensional porphyrin-integrated metal-organic frameworks for enhanced photocatalytic hydrogen peroxide generation in pure water

In the quest for eco-friendly and efficient synthesis of hydrogen peroxide (H2O2), a chemical with extensive applications, photocatalytic production emerges as a promising clean technique. Metal-organic frameworks (MOFs), known for their exceptional porosity and geometric customizability, stand at the forefront of potential photocatalytic materials. Yet, the conventional three-dimensional topologies of MOFs pose a challenge, impeding the swift transit of photogenerated electrons and thereby curbing performance enhancements. In this vein, we have engineered novel 2D porphyrin-based MOFs, specifically Ce-TCPP and La-TCPP, utilizing diverse metal sources while maintaining a consistent topological framework. This design strategy streamlines the electron and hole transport pathways, thus elevating the photocatalytic activity. Delving into the structural nuances of these MOFs, our research unveiled that the photocatalytic activity experienced a marked shift upon altering the metal cluster types. Notably, La-TCPP, as an efficacious catalyst, demonstrated an H2O2 yield of 79.75 μmol/g/h in pure water, sans any sacrificial agents. Rigorous testing confirmed the robust stability of both MOFs. This study marks the inaugural design and synthesis of a single crystal structure of La-TCPP. By strategically varying metal cluster compositions, we have fine-tuned the architecture of two-dimensional MOFs. This approach sheds light on the intricate structure-activity relationship governing the photocatalytic synthesis of H2O2, paving the way for future advancements in the field.

Diet and trophic structure of fishes in the Barents Sea: Effects of size within (ontogenetic) and between species

A large data set on stomach content (over 27,000 individual fish) – collected in the Barents Sea in 2015 – was used to examine ontogenetic and interspecific changes in diet with size for 35 fish species. The analysis combined the use of hierarchical clustering and random forest. Two different diet metrics were used (% weight of prey types per weight of stomach content or per weight of fish, the latter reflecting also feeding intensity), and data were analysed based on average diet of predator groups (species and size groups) across the entire sample series (from the whole Barents Sea in different seasons), or for data broken down by geographical areas and seasons. Similar trophic groups (clusters) were identified for the various data sets suggesting that the results on trophic structure were robust. The trophic groups including size information were broadly similar to groups found earlier with data averaged at species level. Hierarchical clustering produces a hierarchy of trophic groups (or trophic guilds) at various levels of diet dissimilarity. With 12 clusters identified, one cluster had fish as dominant prey, and 5–6 others had either plankton or benthos as dominant prey. The clusters tended to be distinct and homogenous with one dominant prey category in average diet (often > 60 %). This was especially the case for the plankton clusters, with copepods, euphausiids, hyperiid amphipods, or gelatinous zooplankton as dominant prey in each of 4 trophic groups. The benthos clusters tended to be less dissimilar with more overlap in diet composition, with predominance of either hard-shelled forms (echinoderms and molluscs) or softer prey (polychaetes and crustaceans) for groups of clusters. There were clear patterns of ontogenetic shifts in fish diet. Fish that clustered as piscivores at larger size tended to grow from being planktivores when smaller. Smaller species of planktivores or benthivores shifted position among trophic groups but remained within the categories of planktivores or benthivores, respectively. Taxonomy (species) tended to be more important than size for explaining the diet composition of the different clusters of fish predators.

Tail-dependence clustering of time series with spatial constraints

We introduce a clustering method for time series based on tail dependence. Such a method also considers spatial constraints by means of a suitable procedure merging temporal and spatial dependence via extreme-value copulas. The cluster composition depends on the choice of the hyper-parameter α∈(0,1)\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$\\alpha \\in (0,1)$$\\end{document} used to calibrate the contribution of the spatial dependence to the overall dissimilarity. A novel heuristic approach to select α\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$\\alpha$$\\end{document} based on a suitable connectedness index associated to each cluster of the partition is proposed.

Consideration of the Disease Complexes, the Missing Link to Correctly Analyze the Impact of Intercropping on Disease Development

Diversification at the plot level, through the use of intercropping (mixtures of crops), is an alternative to the conventional system of intensive agriculture, based on monospecific, usually single-variety canopies. Intercropping has been shown to provide benefits in terms of disease control. However, competition phenomena and the heterogeneity of the associated crops raise new ecological questions, particularly with regard to the dynamics and evolution of parasite populations. No study has assessed the potential impact of these associations on the dynamics of pathogenic species complexes. Changes in the nutritional status of plants and therefore in their physiological susceptibility to infection within intercropping systems could contribute to an increased diversity of ecological niches and thus affect the composition of the parasitic complex and its spatiotemporal dynamics. In this review, focusing on foliar diseases of fungal origin, and after outlining some elements of the biology and epidemiology of these fungal diseases, we will (i) describe the mechanisms that contribute to the composition of disease clusters and that drive interactions, but we will also review the strategies that these foliar diseases have adopted to deal with these co-infections; (ii) define how intercropping can lead to changes in epidemic dynamics, in particular by presenting the mechanisms that have a direct and indirect effect on disease evolution; and (iii) present the approach that should be adopted to properly study intercropping correctly in a multi-infection situation.

Dual-scale clusters enabling exceptional mechanical properties of a CoNiCr-based MP159 superalloy at 650 °C

Prior or early-stage precipitation products, e.g., GP zones and chemical short-range ordering, attract tons of interests recently due to their extremely small size and notable hardening effects. In this work in a commercial CoNiCr-based MP159 superalloy, we, for the first time, simultaneously introduced two kinds of these products, i.e., the atomic-scale L11 cluster, and the nano L12 cluster with 2.7 nm in size, by simply removing the standard annealing process and directly conducting the intermediate 650 °C tension. The ultra-dense co-existence of these dual-scale clusters generates over 200 MPa hardening effect at the specific 650 °C when compared to the standardly-annealed MP159 alloy that contains only larger (∼6.0 nm) L12 precipitates. High-angle annular dark field-transmission electron microscopy associated with atom probe tomography evidence that firstly, the atomic-scale cluster is of the L11 type, similar to the one observed in the NiCoV medium entropy alloy. And secondly, the composition of the nano L12 cluster is abnormally close to (Ni,Co)3Ti, whose equilibrium crystalline structure is otherwise D024. This likely leads to a high anti-phase boundary energy hence high shearing resistance for dislocations.

Theoretical prediction of low-energy photoelectron spectra of AlnNi- clusters (n = 1-13).

Mixed-metal clusters have long been studied because of their peculiar properties and how they change with cluster size, composition, and charge state and their potential roles in catalysis. The characterization of these clusters is therefore a very important issue. One of the main experimental tools for characterizing their electronic structure is photoelectron spectroscopy. Theoretical computation completes the task by fully determining the structural properties and matching the theoretical predictions to the measured spectra. We present density functional theory computations of the structural, magnetic, and electronic properties of negatively charged mixed AlnNi- clusters with up to 13 Al atoms. The lowest energy structures of the anionic clusters with up to 7 atoms are also found to be low-energy isomers of the neutral counterparts found in the literature. The 13-atom cluster is found to be a quartet and a perfect icosahedron. The predicted photoelectron spectra are also presented and can be used to interpret future experimental data. We also presented indicators that can be used to determine the potential of these systems for single-atom catalysis. These indicators point to smaller clusters to be more reactive as the gap between the Fermi energy and the center of the d-band increases with cluster size and that Ni occupies an internal site for n = 11-13. We speculate that reactivity can be enhanced if one adds an additional Ni atom. The DFT calculations were performed using the Becke exchange and Perdew-Wang/91 correlation functionals (BPW91), a DFT-optimized all-electron basis set for the aluminum atom, and the Stuttgart small core pseudopotential for the Ni atom. All of the computations used the Gaussian 03 software.

The innovativeness of technologies of Industry 4.0 in the modern mining environment

The article presents the results of Industry 4.0 technologies in the modern mining environment. The study is aimed at identifying trends in interest in the topic of innovativeness of Industry 4.0 technologies in the modern global mining environment. To solve the problem of implementing innovations in the context of Industry 4.0 in the modern mining environment, particularly those related to mining science, two approaches were used: the Google Trends search service and the VOSviewer software. The first stage of the study identified the level of interest in mining science and Industry 4.0 in the world. According to the results of the second stage of the study, 8 strategic directions for the development of the mining industry within Industry 4.0 were identified in accordance with the qualitative composition of clusters by keywords in scientific publications, the Scopus scientometric database on the topic of innovativeness of Industry 4.0 technologies in the modern mining environment. It is proposed through amending the mining legislation in accordance with the development of Industry 4.0 technologies for the automation and digitalization of mining significantly increase interest in transformational changes.

Language and identity: The dynamics of linguistic clustering in multinational enterprises

Research on language diversity in international business has shown that language is a core element of one's social identity and employees in MNEs often form homophily-based clusters with those who share their native language. Such clusters can significantly influence communication and knowledge sharing processes within MNEs. However, research assumes that language-based clusters are monolithic in nature. In this study of two MNE headquarters in India, we develop a model to depict the dynamic processes by which language intersects with other salient identity attributes such as gender, regional dialects, and education to change the composition of language-based clusters and alter group dynamics and organizational processes.

Decoration of atomic PdxAuy (1 ≤ x + y ≤ 4) clusters on polyaniline in electrochemical sensing of 1-propanol

Atomic PdxAuy (1 ≤ x + y ≤ 4) clusters are decorated on polyaniline to be used as the catalytic electrode in electrochemical sensors. The current responses in the oxidation of 1-propanol are used to reveal the catalytic activity. Effects of the size, decoration sequence, and composition of the atomic metal clusters decorated on the PANI on the catalytic activity are evaluated. Regarding the size, an odd-even size effect is observed in the atomic pure metal clusters, which the even-numbered pure metal clusters show a higher catalytic activity than the odd-numbered pure metal clusters. For the decoration sequence, the catalytic activity is high when the same metal is decorated in the first two cycles of the cyclic atomic electrodeposition process. For the composition effect, the atomic metal clusters show a high catalytic activity in the oxidation, in the region of second oxidation peak, when there are more Au in the atomic metal clusters.

Trends of physical activity and sedentary behaviours among secondary school students in Singapore: what has changed in 15 years?

ABSTRACT The objective of the current study was to examine the trends of physical activity (PA) and sedentary behaviour (SB) of adolescents in Singapore with two datasets 15 years apart (2006 and 2021). A total sample of 1075 secondary students (mean age = 14.91 ± 0.43 years old) from 15 schools in Singapore took part in the study. A seven-day recall Self-administered Physical Activity Checklist (SAPAC) questionnaire was used to capture time spent on the internet/computer, gaming, homework, reading, sitting and talking/listening to music, telephone, television watching, and PA. Results showed that the 2021 sample spent significantly more time on gaming, homework, sit and talk/listening to music, phone, and PA compared to the 2006 sample, while time spent watching television was significantly lower than the 2006 sample. Both datasets found PA had low or close to zero correlations with all the seven SB, however, the patterns of correlations were different in the two datasets, indicating changes in the trends of SB and PA. Cluster analysis found similar cluster profiles in the two samples but the cluster proportions for certain profiles were different from the two datasets. Significant sex differences were also found in the cluster compositions. Overall, this study shows that PA and SB trends of adolescents have changed significantly.

Immune features revealed by single-cell RNA and single-cell TCR/BCR sequencing in patients with rheumatoid arthritis receiving COVID-19 booster vaccination.

Coronavirus disease 2019 (COVID-19), caused by SARS-CoV-2, have profoundly affected human health. Booster COVID-19 vaccines have demonstrated significant efficacy in reducing infection and severe cases. However, the effects of booster COVID-19 vaccines on key immune cell subsets and their responses in rheumatoid arthritis (RA) are not well understood. By using single-cell RNA sequencing (scRNA-seq) combined with scTCR/BCR-seq analysis, a total of 8 major and 27 minor cell clusters were identified from paired peripheral blood mononuclear cells (PBMCs) which were collected 1 week before and 4 weeks after booster vaccination in stable RA patients. Booster vaccination only had limited impact on the composition and proportions of PBMCs cell clusters. CD8+ cytotoxic T cells (CD8+T_CTL) showed a trend toward an increase after vaccination, while naive B cells and conventional dendritic cells (cDCs) showed a trend toward a decrease. Transcriptomic changes were observed after booster vaccination, primarily involving T/B cell receptor signaling pathways, phagosome, antigen processing and presenting, and viral myocarditis pathways. Interferon (IFN) and pro-inflammatory response gene sets were slightly upregulated across most major cell subpopulations in COVID-19 booster-vaccinated RA individuals. Plasma neutralizing antibody titers significantly increased after booster COVID-19 vaccination (p = 0.037). Single-cell TCR/BCR analysis revealed increased B cell clone expansion and repertoire diversity postvaccination, with no consistent alterations in T cells. Several clonotypes of BCRs and TCRs were identified to be significantly over-represented after vaccination, such as IGHV3-15 and TRBV28. Our study provided a comprehensive single-cell atlas of the peripheral immune response and TCR/BCR immune repertoire profiles to inactivated SARS-CoV-2 booster vaccination in RA patients, which helps us to understand vaccine-induced immune responses better.

Simulation of Full HIV Cluster Networks in a Nationally Representative Model Indicates Intervention Opportunities.

Clusters of rapid HIV transmission in the United States are increasingly recognized through analysis of HIV molecular sequence data reported to the National HIV Surveillance System. Understanding the full extent of cluster networks is important to assess intervention opportunities. However, full cluster networks include undiagnosed and other infections that cannot be systematically observed in real life. We replicated HIV molecular cluster networks during 2015-2017 in the United States using a stochastic dynamic network simulation model of sexual transmission of HIV. Clusters were defined at the 0.5% genetic distance threshold. Ongoing priority clusters had growth of ≥3 diagnoses/year in multiple years; new priority clusters first had ≥3 diagnoses/year in 2017. We assessed the full extent, composition, and transmission rates of new and ongoing priority clusters. Full clusters were 3-9 times larger than detected clusters, with median detected cluster sizes in new and ongoing priority clusters of 4 (range 3-9) and 11 (range 3-33), respectively, corresponding to full cluster sizes with a median of 14 (3-74) and 94 (7-318), respectively. A median of 36.3% (range 11.1%-72.6%) of infections in the full new priority clusters were undiagnosed. HIV transmission rates in these clusters were >4 times the overall rate observed in the entire simulation. Priority clusters reflect networks with rapid HIV transmission. The substantially larger full extent of these clusters, high proportion of undiagnosed infections, and high transmission rates indicate opportunities for public health intervention and impact.

Measurement report: Insights into the chemical composition and origin of molecular clusters and potential precursor molecules present in the free troposphere over the southern Indian Ocean: observations from the Maïdo Observatory (2150 m a.s.l., Réunion)

Abstract. New particle formation (NPF) in the free troposphere (FT) is thought to be a significant source of particles over the oceans. The entrainment of particles initially formed in the marine FT is further suspected to be a major contributor to cloud condensation nuclei (CCN) number concentrations in the marine boundary layer (BL). Yet, little is known about the process and, more broadly, about the composition of the marine FT, which remains poorly explored due to access difficulties. Here we report measurements performed in April 2018 at the Maïdo Observatory with a nitrate-based chemical ionization atmospheric pressure interface time-of-flight mass spectrometer, which have allowed the first molecular-level characterization of the remote marine FT composition. A number of molecules and clusters were identified and classified into nine groups according to their chemical composition; among the identified species, the groups containing methanesulfonic acid (MSA) and C2 amines show signals that are on average significantly higher when the site is under conditions representative of the marine FT (compared to the BL). The correlation analysis revealed apparent connections between the signals of the identified compounds and several variables concurrently measured at the site (under FT conditions) or related to air mass history, suggesting that oxalic acid, malonic acid, and observed C2 amines could be of terrestrial origin, with, in addition, a possible marine source for oxalic acid and amines, while iodic acid, sulfur species, and maleic acid have a dominant marine origin. Identification of FT conditions at the site was based on the analysis of the standard deviation of the wind direction; this parameter, which can easily be derived from continuous measurements at the site, is shown in the first part of the study to be a relevant tracer when compared to predictions from the Meso-NH atmospheric model. Similar to other high-altitude sites, FT conditions are mainly encountered at night at Maïdo; therefore, the link to NPF could not be established, and further research is needed to assess the composition of precursors to nanoparticle formation in the marine FT.