Hasil untuk "Environmental sciences"

Menampilkan 20 dari ~8380088 hasil · dari arXiv, DOAJ, Semantic Scholar

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S2 Open Access 2013
What is conservation physiology? Perspectives on an increasingly integrated and essential science

S. Cooke, L. Sack, C. Franklin et al.

The definition of ‘conservation physiology’ is refined to be more inclusive, with an emphasis on characterizing diversity, understanding and predicting responses to environmental change and stressors, and generating solutions. The integrative discipline is focused on mechanisms and uses physiological tools, concepts, and knowledge to advance conservation and resource management.

464 sitasi en Biology, Medicine
arXiv Open Access 2026
The Zhamanshin Impact Event: Potential Implications for Environmental Responses and Biological Linkages on Earth and Beyond

James B. Garvin, Connor J. Anderson, Katherine A. Melocik et al.

At least one large-body (diameter > 1.1 km) hypervelocity cratering event occurred during ~ 0.8-0.90 Ma (Zhamanshin, Kazakhstan) in the Middle Pleistocene Transition period. Analysis designed to reduce uncertainty in the dimensions of the Zhamanshin structure employing high resolution topography demonstrated that it likely generated a ~ 26.5 km diameter multi-ring crater. This is at least two times larger than the current best estimates. Using a range of accepted impactor sizes, velocities, compositions, and angles of impact, such impacts typically yield kinetic energies of impact over 240,000 Megatons (TNT). Explosive energetic events of this magnitude (e.g., Yellowstone Caldera) at other times (K-Pg) have created global environmental effects. The factor of two discrepancy in the dimensions of Zhamanshin increases the kinetic energy yield by factors of 7-10, with significantly larger environmental consequences. This justifies examination of rapid climate transitions linked to biological consequences, including those related to environmental perturbations, at ~0.9 Ma.

en astro-ph.EP
arXiv Open Access 2026
Accounting for environmental awareness in wheat production through Life Cycle Assessment

Gianfranco Giulioni, Edmondo Di Giuseppe, Arianna Di Paola

This paper presents a modeling framework for simulating the decision-making processes of artificial farms populating an agent-based model for the Italian wheat production system. The decision process is based on a mathematical programming model with which farms (i.e., agents) decide the target yield (production per hectare) and the mix of inputs needed to obtain such production, namely 1) fertilizers, 2) herbicides, and 3) insecticides. The environmental impacts of conventional production practices are assessed through a Life Cycle Assessment (LCA), using the ReCiPe 2016 methodology at the Endpoint level. Agents are made aware of the environmental consequences of their choices through two indicators: Disability-Adjusted Life Years (DALYs), which capture human health impacts, and the number of species lost per year, reflecting impacts on ecosystems. By internalizing this information, agents can make more balanced and sustainable production decisions.

en econ.GN
DOAJ Open Access 2026
Spatiotemporal heterogeneity and driving forces of construction carbon emissions in transitional regions: evidence from six provinces in Central China

Yinkai Wei, Wudong Ban

This study explores the spatiotemporal patterns of construction carbon emissions in Central China (Anhui, Shanxi, Jiangxi, Henan, Hunan, Hubei) under China's carbon peak and neutrality goals. Using certified construction data, NPP–VIIRS nighttime light data, energy statistics, and socioeconomic panel data from 2012 to 2025, we examine emission dynamics and spatial heterogeneity. Results show that total emissions reached 1.039 billion tons of CO₂ equivalent, with Shanxi accounting for over 20%. Spatial clustering exhibited a fluctuating downward trend, with High–High clusters in Shanxi and northern Henan, and Low–Low clusters in southern Anhui, western Hubei, and northern Jiangxi. Geodetector results reveal that regional GDP and secondary industry output were dominant drivers, and their interactions with population and technology investment reached a maximum q‑statistic of 0.98. These findings support targeted low-carbon policies for the construction sector in transitional regions.

Environmental sciences
S2 Open Access 2021
Citizen Science and Biological Invasions: A Review

J. Encarnação, M. Teodósio, P. Morais

Biological invasions are among the most challenging ecological and conservation riddles of our times. Fortunately, citizen science projects became a valuable tool to detect non-indigenous species (NIS), document their spread, prevent dispersion, and eradicate localized populations. We evaluated the most undisputed definitions of citizen science and proposed that a combination of two of them is a better reflection of what citizen science has become. Thus, citizen science is any environmental and/or biological data collection and analysis, including data quality control, undertaken by members of the general public, as individuals or as organized groups of citizens, with the guidance and/or assistance of scientists toward solving environmental and/or community questions. With this review, we also assessed how citizen science has been advancing biological invasions research and its focus, by analyzing 126 peer-reviewed articles that used citizen science methods or data concerning NIS. Most of the articles studied terrestrial species (68%) and terrestrial plants were the most studied group (22.7%). Surprisingly, most first detection reports were of non-indigenous marine fish probably due to the constraints in accessing aquatic ecosystems which delays the detection of new NIS. Citizen science projects running over broad geographical areas are very cost-effective for the early detection of NIS, regardless of the studied environment. We also discuss the applicability and need to adapt the methods and approaches toward the studied ecosystem and species, but also the profile of the participating citizens, their motivations, level of engagement, or social status. We recommend authors to better acknowledge the work done by contributing citizens, and the putative limitations of data generated by citizen science projects. The outreach planning of citizen science projects is also evaluated, including the use of dedicated web platforms vs. pre-existent and disseminated web platforms, while discussing how such outreach actions can be maximized. Lastly, we present a framework that contextualizes the contributions of citizen science, scientific research, and regional and national stakeholders toward the integrated management of biological invasions.

140 sitasi en
arXiv Open Access 2025
Latent Multi-view Learning for Robust Environmental Sound Representations

Sivan Ding, Julia Wilkins, Magdalena Fuentes et al.

Self-supervised learning (SSL) approaches, such as contrastive and generative methods, have advanced environmental sound representation learning using unlabeled data. However, how these approaches can complement each other within a unified framework remains relatively underexplored. In this work, we propose a multi-view learning framework that integrates contrastive principles into a generative pipeline to capture sound source and device information. Our method encodes compressed audio latents into view-specific and view-common subspaces, guided by two self-supervised objectives: contrastive learning for targeted information flow between subspaces, and reconstruction for overall information preservation. We evaluate our method on an urban sound sensor network dataset for sound source and sensor classification, demonstrating improved downstream performance over traditional SSL techniques. Additionally, we investigate the model's potential to disentangle environmental sound attributes within the structured latent space under varied training configurations.

en cs.SD
arXiv Open Access 2025
A Two-Stage Stochastic Optimization Framework for Environmentally Sensitive Oil Spill Response Resource Allocation in the Arctic

Md Ashiqur Rahman, Mustofa Tanbir Kuhel, Clara Novoa

The risk of oil spills in the Alaskan Arctic has become an urgent environmental and logistical concern as maritime traffic increases under climate driven sea ice retreat. Traditional deterministic response planning models fail to represent key uncertainties, including variable spill magnitudes, changing environmental sensitivity, and infrastructure limitations. This study develops a two-stage stochastic mixed integer linear programming framework that jointly optimizes the location of oil spill response stations and the allocation of heterogeneous resources across multiple probabilistic spill scenarios. The model integrates a weighted objective that combines spill volume, environmental sensitivity index (ESI), response time, and costs for station setup, deployment, and inter station transfer. Separate importance weights for coverage and cost, together with internal ecological weights, allow decision makers to balance ecological protection and operational efficiency. Data was compiled from Alaska Department of Environmental Conservation spill records and National Oceanic and Atmospheric Administration ESI layers and are converted into model ready scenarios through harmonization and sampling. The model is solved with the Gurobi optimizer, and sensitivity analysis is performed over 324 combinations of importance and ecological weights. Results show about a 35.45% percent improvement in response effectiveness over deterministic methods, as confirmed by the value of the stochastic solution, and reveal clear tradeoffs between cost and ecological coverage. The framework provides a data driven decision support tool for Arctic emergency planners that simultaneously accounts for uncertainty, environmental sensitivity, and realistic logistical constraints.

en math.OC
DOAJ Open Access 2025
Spatiotemporal eDNA Monitoring of Marine Biodiversity in a Hyperurbanised Coastal Environment

Zhi Ting Yip, Zheng Bin Randolph Quek, Danwei Huang

ABSTRACT Environmental DNA (eDNA) provides a powerful means of monitoring biodiversity, offering high taxonomic resolution and broad spatial coverage beyond traditional methods. To characterize ecological communities, it is critical to understand shifts in species composition through time to potentially differentiate resident from transient species in the studied habitats. This study used eDNA metabarcoding to examine temporal and spatial patterns of α‐ and β‐diversity across three distinct habitat types (sandy, rocky, and mangrove) at four coastal sites in Singapore over 1 year. We targeted invertebrates using the cytochrome oxidase subunit I (COI) gene and vertebrates using the 16S rRNA gene. We recorded lower diversity at nature reserves, which harbor more rare species than unprotected habitats. β‐diversity differed significantly by site and time for both markers, though β‐dispersion generally remained consistent over time within sites for both invertebrate and vertebrate communities. The difference in marine metazoan communities was driven by high spatial and temporal turnover without strong directional trends across Singapore's coastal sites. These patterns reflect distinct, cohesive communities with limited seasonality, characteristic of equatorial climates. However, certain taxa showed monsoon‐associated distributions, except in mangrove habitats. Importantly, we suggest more mid‐ to long‐term surveys to elucidate the community of resident species. Our findings highlight the value of using eDNA methods to identify dynamic biodiversity patterns and support its use in long‐term ecological monitoring and conservation planning.

Environmental sciences, Microbial ecology
DOAJ Open Access 2025
Far-future climate projection of the Adriatic marine heatwaves: a kilometre-scale experiment under extreme warming

C. Denamiel, C. Denamiel

<p>The impact of a far-future extreme warming scenario on Adriatic marine heatwave (MHW) characteristics – including intensity, duration, spatial extent, and associated environmental drivers – is assessed using the Adriatic Sea and Coast (AdriSC) kilometre-scale atmosphere–ocean model. The main aim of this study is to evaluate the added value and limitations of the pseudo-global-warming (PGW) approach, used to force the far-future AdriSC simulation, in projecting Adriatic MHWs. In line with existing knowledge, the results indicate a significant increase in MHW intensity along with a notable expansion in spatial coverage, particularly in the central and eastern Adriatic. Seasonal patterns show that the most intense MHWs occur between May and September, with events extending into late autumn and early winter under extreme warming. This study also reveals several novel insights. First, the Po River plume is identified as a key factor for the onset and decline of MHWs. Lower river discharges are associated with intense MHW onset, while higher discharges aid in heat dissipation during decline phases. As air–sea heat fluxes are demonstrated to play a critical role in MHW onset along the plume, these findings suggest that MHWs are more likely to develop and persist under low Po River discharge conditions, when water clarity increases and solar radiation absorption is enhanced due to reduced suspended sediments and organic matter. Second, the study identifies a gap in MHW activity, potentially linked to the Eastern Mediterranean Transient, highlighting the influence of natural variability on MHW dynamics. However, no correlation is found with the Ionian–Adriatic Bimodal Oscillating System, suggesting the need for further research on oceanographic influences. Consequently, the PGW approach is found to effectively capture the thermodynamic changes influencing the MHWs in the Adriatic Sea despite potentially oversimplifying future MHW dynamics as it assumes stationarity in climate signals. Finally, these findings underscore the urgent need for adaptive strategies to mitigate the impacts of intensified MHWs on marine ecosystems and coastal communities, particularly in vulnerable nearshore areas. Future research should incorporate ensembles of high-resolution projections and assess additional climate stressors to provide a more comprehensive understanding of Adriatic MHWs under future warming.</p>

Geography. Anthropology. Recreation, Environmental sciences
DOAJ Open Access 2025
Sensitivity of aerosol and cloud properties to coupling strength of marine boundary layer clouds over the northwest Atlantic

K. Zeider, K. McCauley, K. McCauley et al.

<p>Quantifying the degree of coupling between marine boundary layer (MBL) clouds and the surface is critical for understanding the evolution of low clouds and explaining the vertical distribution of aerosols and microphysical cloud properties. Previous work has characterized the boundary layer as either coupled or decoupled, but this study rather considers four degrees of coupling, ranging from strongly to weakly coupled. We use aircraft data from the NASA Aerosol Cloud meTeorology Interactions oVer the western ATlantic Experiment (ACTIVATE) to assess aerosol and cloud characteristics for the following four regimes, quantified using differences in liquid water potential temperature (<span class="inline-formula"><i>θ</i><sub>ℓ</sub></span>) and total water mixing ratio (<span class="inline-formula"><i>q</i><sub>t</sub></span>) between flight data near the surface level (<span class="inline-formula">∼150</span> m) and directly below cloud bases: strong coupling (<span class="inline-formula">Δ<i>θ</i><sub>ℓ</sub>≤1.0</span> K, <span class="inline-formula">Δ<i>q</i><sub>t</sub>≤0.8</span> <span class="inline-formula">g kg<sup>−1</sup></span>), moderate coupling with high <span class="inline-formula">Δ<i>θ</i><sub>ℓ</sub></span> (<span class="inline-formula">Δ<i>θ</i><sub>ℓ</sub>&gt;1.0</span> K, <span class="inline-formula">Δ<i>q</i><sub>t</sub>≤0.8</span> <span class="inline-formula">g kg<sup>−1</sup></span>), moderate coupling with high <span class="inline-formula">Δ<i>q</i><sub>t</sub></span> (<span class="inline-formula">Δ<i>θ</i><sub>ℓ</sub>≤1.0</span> K, <span class="inline-formula">Δ<i>q</i><sub>t</sub>&gt;0.8</span> <span class="inline-formula">g kg<sup>−1</sup></span>), and weak coupling (<span class="inline-formula">Δ<i>θ</i><sub>ℓ</sub>&gt;1.0</span> K, <span class="inline-formula">Δ<i>q</i><sub>t</sub>&gt;0.8</span> <span class="inline-formula">g kg<sup>−1</sup></span>). Results show that (i) turbulence is greater in the strong coupling regime compared to the weak coupling regime, with the former corresponding to more vertical homogeneity in 550 nm aerosol scattering, integrated aerosol volume concentration, and giant aerosol number concentration (<span class="inline-formula"><i>D</i><sub>p</sub>&gt;3</span> <span class="inline-formula">µm</span>) coincident with increased MBL mixing; (ii) cloud drop number concentration is greater during periods of strong coupling due to the greater upward vertical velocity and subsequent activation of particles; and (iii) sea salt tracer species (<span class="inline-formula">Na<sup>+</sup></span>, <span class="inline-formula">Cl<sup>−</sup></span>, <span class="inline-formula">Mg<sup>2+</sup></span>, <span class="inline-formula">K<sup>+</sup></span>) are present in greater concentrations in the strong coupling regime compared to weak coupling, while tracers of continental pollution (<span class="inline-formula">Ca<sup>2+</sup></span>, non-sea-salt (nss) <span class="inline-formula"><math xmlns="http://www.w3.org/1998/Math/MathML" id="M25" display="inline" overflow="scroll" dspmath="mathml"><mrow class="chem"><msup><msub><mi mathvariant="normal">SO</mi><mn mathvariant="normal">4</mn></msub><mrow><mn mathvariant="normal">2</mn><mo>-</mo></mrow></msup></mrow></math><span><svg:svg xmlns:svg="http://www.w3.org/2000/svg" width="34pt" height="16pt" class="svg-formula" dspmath="mathimg" md5hash="95945f53b3fbc040b883e7623294c88b"><svg:image xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="acp-25-2407-2025-ie00001.svg" width="34pt" height="16pt" src="acp-25-2407-2025-ie00001.png"/></svg:svg></span></span>, <span class="inline-formula"><math xmlns="http://www.w3.org/1998/Math/MathML" id="M26" display="inline" overflow="scroll" dspmath="mathml"><mrow class="chem"><msup><msub><mi mathvariant="normal">NO</mi><mn mathvariant="normal">3</mn></msub><mo>-</mo></msup></mrow></math><span><svg:svg xmlns:svg="http://www.w3.org/2000/svg" width="30pt" height="15pt" class="svg-formula" dspmath="mathimg" md5hash="854abc5cffcc47c7a8d3c23f4d8e54ba"><svg:image xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="acp-25-2407-2025-ie00002.svg" width="30pt" height="15pt" src="acp-25-2407-2025-ie00002.png"/></svg:svg></span></span>, oxalate, and <span class="inline-formula"><math xmlns="http://www.w3.org/1998/Math/MathML" id="M27" display="inline" overflow="scroll" dspmath="mathml"><mrow class="chem"><msup><msub><mi mathvariant="normal">NH</mi><mn mathvariant="normal">4</mn></msub><mo>+</mo></msup></mrow></math><span><svg:svg xmlns:svg="http://www.w3.org/2000/svg" width="29pt" height="14pt" class="svg-formula" dspmath="mathimg" md5hash="23356e89e697acb5868d09068ed8ea2c"><svg:image xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="acp-25-2407-2025-ie00003.svg" width="29pt" height="14pt" src="acp-25-2407-2025-ie00003.png"/></svg:svg></span></span>) are higher in mass fraction for the weak coupling regime. Additionally, pH and <span class="inline-formula"><math xmlns="http://www.w3.org/1998/Math/MathML" id="M28" display="inline" overflow="scroll" dspmath="mathml"><mrow class="chem"><msup><mi mathvariant="normal">Cl</mi><mo>-</mo></msup><mo>:</mo><msup><mi mathvariant="normal">Na</mi><mo>+</mo></msup></mrow></math><span><svg:svg xmlns:svg="http://www.w3.org/2000/svg" width="46pt" height="12pt" class="svg-formula" dspmath="mathimg" md5hash="de49dbf95b867cd2cc39cd77ac0f153e"><svg:image xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="acp-25-2407-2025-ie00004.svg" width="46pt" height="12pt" src="acp-25-2407-2025-ie00004.png"/></svg:svg></span></span> (a marker for chloride depletion) are consistently lower in the weak coupling regime. There were also differences between the two moderate regimes: the moderate with high <span class="inline-formula">Δ<i>q</i><sub>t</sub></span> regime had greater turbulent mixing and sea salt concentrations in cloud water, along with smaller differences in integrated volume and giant aerosol number concentration across the two vertical levels compared. This work shows value in defining multiple coupling regimes (rather than the traditional coupled versus decoupled) and demonstrates differences in aerosol and cloud behavior in the MBL for the various regimes.</p>

Physics, Chemistry
DOAJ Open Access 2025
Residential heating emissions for the Western Balkans

C. Asker, E. van Dongen, O. Tasse

<p>Air pollution adversely affects health, ecosystems, and infrastructure. In the <i>Western Balkans</i> (Albania, Bosnia and Herzegovina, Kosovo<span class="note-anchor" id="fna_Ch1.Footn1"><a href="#fn_Ch1.Footn1"><sup>1</sup></a></span>, Montenegro, the Republic of North Macedonia, and Serbia), the air pollution situation is more adverse than in the European Union in general. Understanding the air quality situation requires high-quality emission data with a high-resolution spatial distribution, especially for enabling remediation efforts, which is lacking in the Western Balkan region.</p> <p>In this work, we have calculated air pollution emissions from the heating of individual housing units in the Western Balkan region. The basis for the dataset is a geographical dataset of buildings detected from satellite imagery by artificial intelligence (AI) methods. The building data have been combined with geospatial land-use datasets and statistical data for heating needs for residential buildings in the countries included and finally with emission factors to calculate the heating emissions.</p> <p>Using this novel approach, the resulting datasets provide high-resolution heating emission data for common pollutants and are published as open data (<a href="https://doi.org/10.5281/zenodo.13906810">https://doi.org/10.5281/zenodo.13906810</a>, <span class="cit" id="xref_altparen.1"><a href="#bib1.bibx2">Asker</a>, <a href="#bib1.bibx2">2024</a></span>). When comparing national totals for emissions, the datasets in this work are comparable to other, spatially coarser datasets, though the agreement strongly depends on the fuel usage data for each country/region.</p>

Environmental sciences, Geology
arXiv Open Access 2024
Trainingless Adaptation of Pretrained Models for Environmental Sound Classification

Noriyuki Tonami, Wataru Kohno, Keisuke Imoto et al.

Deep neural network (DNN)-based models for environmental sound classification are not robust against a domain to which training data do not belong, that is, out-of-distribution or unseen data. To utilize pretrained models for the unseen domain, adaptation methods, such as finetuning and transfer learning, are used with rich computing resources, e.g., the graphical processing unit (GPU). However, it is becoming more difficult to keep up with research trends for those who have poor computing resources because state-of-the-art models are becoming computationally resource-intensive. In this paper, we propose a trainingless adaptation method for pretrained models for environmental sound classification. To introduce the trainingless adaptation method, we first propose an operation of recovering time--frequency-ish (TF-ish) structures in intermediate layers of DNN models. We then propose the trainingless frequency filtering method for domain adaptation, which is not a gradient-based optimization widely used. The experiments conducted using the ESC-50 dataset show that the proposed adaptation method improves the classification accuracy by 20.40 percentage points compared with the conventional method.

en cs.SD, eess.AS
arXiv Open Access 2024
Projection Mapping under Environmental Lighting by Replacing Room Lights with Heterogeneous Projectors

Masaki Takeuchi, Hiroki Kusuyama, Daisuke Iwai et al.

Projection mapping (PM) is a technique that enhances the appearance of real-world surfaces using projected images, enabling multiple people to view augmentations simultaneously, thereby facilitating communication and collaboration. However, PM typically requires a dark environment to achieve high-quality projections, limiting its practicality. In this paper, we overcome this limitation by replacing conventional room lighting with heterogeneous projectors. These projectors replicate environmental lighting by selectively illuminating the scene, excluding the projection target. Our contributions include a distributed projector optimization framework designed to effectively replicate environmental lighting and the incorporation of a large-aperture projector, in addition to standard projectors, to reduce high-luminance emitted rays and hard shadows -- undesirable factors for collaborative tasks in PM. We conducted a series of quantitative and qualitative experiments, including user studies, to validate our approach. Our findings demonstrate that our projector-based lighting system significantly enhances the contrast and realism of PM results even under environmental lighting compared to typical lights. Furthermore, our method facilitates a substantial shift in the perceived color mode from the undesirable aperture-color mode, where observers perceive the projected object as self-luminous, to the surface-color mode in PM.

en cs.GR, cs.HC
arXiv Open Access 2024
Environmental permittivity-asymmetric BIC metasurfaces with electrical reconfigurability

Haiyang Hu, Wenzheng Lu, Rodrigo Berte et al.

In the rapidly evolving field of nanophotonics, achieving precise spectral and temporal light manipulation at the nanoscale remains a critical challenge. While photonic bound states in the continuum (BICs) have emerged as a powerful means of controlling light, their common reliance on geometrical symmetry breaking for obtaining tailored resonances makes them highly susceptible to fabrication imperfections and fundamentally limits their maximum resonance quality factor. Here, we introduce the concept of environmental symmetry breaking by embedding identical resonators into a surrounding medium with carefully placed regions of contrasting refractive indexes, activating permittivity-driven quasi-BIC resonances without any alterations of the underlying resonator geometry and unlocking an additional degree of freedom for light manipulation through actively tuning the surrounding refractive index contrast. We demonstrate this concept by integrating polyaniline (PANI), an electro-optically active polymer, to achieve electrically reconfigurable qBICs. This integration not only demonstrates rapid switching speeds, and exceptional durability but also significantly boosts the system's optical response to environmental perturbations. Our strategy significantly expands the capabilities of resonant light manipulation through permittivity modulation, opening avenues for on-chip optical devices, advanced sensing, and beyond.

en physics.optics, physics.app-ph
DOAJ Open Access 2024
Comparison between Traditional and Novel NMR Methods for the Analysis of Sicilian Monovarietal Extra Virgin Olive Oils: Metabolic Profile Is Influenced by Micro-Pedoclimatic Zones

Archimede Rotondo, Giovanni Bartolomeo, Irene Maria Spanò et al.

Nuclear magnetic resonance (NMR) metabolomic analysis was applied to investigate the differences within nineteen Sicilian <i>Nocellara del Belice</i> monovarietal extra virgin olive oils (EVOOs), grown in two zones that are different in altitude and soil composition. Several classes of endogenous olive oil metabolites were quantified through a nuclear magnetic resonance (NMR) three-experiment protocol coupled with a yet-developed data-processing called MARA-NMR (Multiple Assignment Recovered Analysis by Nuclear Magnetic Resonance). This method, taking around one-hour of experimental time per sample, faces the possible quantification of different class of compounds at different concentration ranges, which would require at least three alternative traditional methods. NMR results were compared with the data of traditional analytical methods to quantify free fatty acidity (FFA), fatty acid methyl esters (FAMEs), and total phenol content. The presented NMR methodology is compared with traditional analytical practices, and its consistency is also tested through slightly different data treatment. Despite the rich literature about the NMR of EVOOs, the paper points out that there are still several advances potentially improving this general analysis and overcoming the other cumbersome and multi-device analytical strategies. Monovarietal EVOO’s composition is mainly affected by pedoclimatic conditions, in turn relying upon the nutritional properties, quality, and authenticity. Data collection, analysis, and statistical processing are discussed, touching on the important issues related to the climate changes in Sicily and to the specific influence of pedoclimatic conditions.

Organic chemistry
arXiv Open Access 2023
Star formation concentration as a tracer of environmental quenching in action: a study of the Eagle and C-Eagle simulations

Di Wang, Claudia D. P. Lagos, Scott M. Croom et al.

We study environmental quenching in the Eagle}/C-Eagle cosmological hydrodynamic simulations over the last 11 Gyr (i.e. $z=0-2$). The simulations are compared with observations from the SAMI Galaxy Survey at $z=0$. We focus on satellite galaxies in galaxy groups and clusters ($10^{12}\,\rm M_{\odot}$ $\lesssim$ $M_{200}$ < $3 \times 10^{15}\, \rm M_{\odot}$). A star-formation concentration index [$C$-index $= \log_{10}(r_\mathrm{50,SFR} / r_\mathrm{50,rband})$] is defined, which measures how concentrated star formation is relative to the stellar distribution. Both Eagle/C-Eagle and SAMI show a higher fraction of galaxies with low $C$-index in denser environments at $z=0-0.5$. Low $C$-index galaxies are found below the SFR-$M_{\star}$ main sequence (MS), and display a declining specific star formation rate (sSFR) with increasing radii, consistent with ``outside-in'' environmental quenching. Additionally, we show that $C$-index can be used as a proxy for how long galaxies have been satellites. These trends become weaker at increasing redshift and are absent by $z=1-2$. We define a quenching timescale $t_{\rm quench}$ as how long it takes satellites to transition from the MS to the quenched population. We find that simulated galaxies experiencing ``outside-in'' environmental quenching at low redshift ($z=0\sim0.5$) have a long quenching timescale (median $t_{\rm quench}$ > 2 Gyr). The simulated galaxies at higher redshift ($z=0.7\sim2$) experience faster quenching (median $t_{\rm quench}$ < 2Gyr). At $z\gtrsim 1-2$ galaxies undergoing environmental quenching have decreased sSFR across the entire galaxy with no ``outside-in'' quenching signatures and a narrow range of $C$-index, showing that on average environmental quenching acts differently than at $z\lesssim 1$.

en astro-ph.GA

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