Physical Analysis Research Articles

Hiding in plain sight: The prevalence and impact of trions and Fermi polarons in transient absorption spectroscopy experiments of 2D semiconductors.

Transient absorption (TA) spectroscopy is one of the most popular experimental methods to measure the excited state lifetimes and charge carrier recombination mechanisms in two dimensional (2D) semiconductors. This fundamental information is essential for designing and optimizing the next generation of ultrathin and lightweight 2D semiconductor-based optoelectronic devices. However, the interpretation of TA spectroscopy data varies across the community. The community lacks a unifying physical explanation for how and why experimental variables such as incident light intensity, sample-substrate interactions, and/or applied bias affect TA spectral data. This Perspective (1) compares the physical chemistry TA literature to nanomaterial physics literature from a historical perspective, (2) reviews multiple physical explanations that the TA community developed to explain spectral features and experimental trends, (3) provides a unifying explanation for how and why trions-and, more generally, Fermi polarons-contribute to TA spectra, and (4) quantifies the extent to which various physical interpretations and data analysis procedures yield different timescales and mechanisms for the same set of experimental results. We highlight the importance of considering trions/Fermi polarons in TA measurements and their implications for advancing our understanding of 2D material properties.

Alternative substrates for the production of container-grown Mexican marigold

ABSTRACT Objective: To evaluate substrate mixtures for the production of Mexican marigolds grown in containers in the community of Santa Cruz Itundujia, Oaxaca. Methods: Four soil mixtures were tested: 1) 70% ocote pine needles + 30% soil, 2) 70% leaf mold + 30% soil, 3) 70% river sand + 30% soil, and 4) 70% sawdust + 30% soil. Mexican marigold (Tagetes erecta) var. Inca II Deep Orange plants were established in pots under open field conditions. Height, number of leaves, plant width, branching, leaf area, and number of buds were evaluated in the different phenological stages of the plant; the last measurement was made at the flowering stage. Soil fertility parameters were analyzed, and physical analysis of the substrates was performed. Results: The treatments produced differential results; ocote pine needles + soil and leaf mold + soil were the best for producing container-grown marigolds. The lowest results in yield variables were found with the river sand + soil mixture. Implications: Using local and inexpensive substrates will impact production costs for marigold farmers. Currently, a variety of commercial mixes and substrates of foreign origin are available and used for the production of container-grown plants. Conclusions: The best results were obtained with organic substrates, specifically with ocote pine needles and leaf mold. The mixture with sawdust did not show good results in the tested variables, possibly due to this material’s high carbon/nitrogen ratio. The lowest results were obtained with the sand + soil treatment. Keywords: Asteraceae, yield, sawdust, needle, Tagetes erecta

Transformative effects of infrared-assisted hot air drying on neera syrup concentrated coconut flakes: a comprehensive evaluation of physical properties, composition analysis and antioxidant profiles

Transformative effects of infrared-assisted hot air drying on neera syrup concentrated coconut flakes: a comprehensive evaluation of physical properties, composition analysis and antioxidant profiles

Recent Experimental Advances in Solid–Liquid Composites for Impact and Blast Mitigation

The development of high-performance composites for mechanical energy dissipation during impact or explosive events is of vital importance for the safety of personnel and infrastructures. Solid–liquid composites are an emerging class of energy absorbers where a liquid-phase filler is seamlessly integrated into a solid matrix to enhance the impact resistance of the protection target. This innovative approach leverages the distinct properties of both phases and the unique interactions between them to achieve superior performance under high-impact conditions. This paper aims to review the liquid-phase materials used in solid–liquid composites, ranging from neat liquids to complex fluids, including liquid nanofoam and shear-thickening fluids, to provide an in-depth analysis of the fundamental physics underpinning the resulting solid–liquid composites, and to explore how their unique properties contribute to enhanced impact resistance and energy absorption. Furthermore, this paper evaluates the advantages and limitations of these solid–liquid composites and offers insights into future directions for the development of solid–liquid composites in various fields, including personal protective equipment, automotive safety systems, and structural protection.

Experimental Investigations of the Influence of Spent Coffee Grounds Content on PLA Based Composite for 3D Printing

Nowadays Fused Deposition Modeling, a widely utilized additive manufacturing technology, is significantly transforming as modern production processes. Beyond basic uses to it role in sustainability, Fused Deposition Modeling offers processing potential for implanting circular economy by reducing virgin materials consumption and enhance the integration of waste food for sustainable 3D printing. This research paper investigated the production of new composite materials based on spent coffee grounds. In addition, PLA and SCG at various contents (0, 3, 5, 10, and 15 wt%) were dried and premixed, then processed into PLA/SCG composite pellets using twin-screw extrusion. These pellets were successfully converted into filaments and subsequently used for 3D printing. The effect of spent coffee grounds in PLA composites was investigated via physical and mechanical analysis of 3D printed samples. Regarding density measurements, results revealed that adding up to 5 wt% of spent coffee grounds increased the density while further additions led to a decrease which due to the printing parameters such as extrusion temperature and nozzle diameter. Considering the mechanical properties, the Young’s modulus increased once the spent coffee grounds content reached 3 wt% and then decreased. In the other hand, there was no enhancement in tensile strength and elongation at break which corroborating with density measurements. This mainly contributed to the changes in mechanical properties caused by printing parameters. This study demonstrates that coffee waste can be used as a filler in environmentally friendly composites for 3D printing, with a maximum SCG content of 15 wt%. This approach not only promotes the reuse of coffee waste but also reduces the cost of traditional PLA filaments.

Les Houches guide to reusable ML models in LHC analyses

With the increasing usage of machine-learning in high-energy physics analyses, the publication of the trained models in a reusable form has become a crucial question for analysis preservation and reuse. The complexity of these models creates practical issues for both reporting them accurately and for ensuring the stability of their behaviours in different environments and over extended timescales. In this note we discuss the current state of affairs, highlighting specific practical issues and focusing on the most promising technical and strategic approaches to ensure trustworthy analysis-preservation. This material originated from discussions in the LHC Reinterpretation Forum and the 2023 PhysTeV workshop at Les Houches.

Anthropogenic Impact on Soils of Cities Irkutsk, Angarsk

The morphological field description of soil profiles of the territory of Irkutsk region was carried out. Samples of soils, soil-forming rocks and vegetation were taken for further physical and chemical analyses to determine soil properties in the studied areas. Sample preparation of soils was carried out, phytotoxicity of soils was analyzed. Processing of the obtained data was carried out, as a result of which the percentage of germination of radish seeds in the upper horizons of soils of the key areas of Irkutsk and Angarsk cities was revealed, the length of shoots and the length of roots in the soils of the studied samples were measured, the index of soil toxicity was calculated.

Quality evaluation of innovative buttermilk biscuits produced from orange-flesh sweet potato flour infused with coconut

IntroductionThis study was undertaken to evaluate a value-added innovative buttermilk biscuit made from orange flesh sweet potato (OFSP) flour, infused with coconut. It underscores the importance of food utilisation through alternatives to wheat flour contributing to food and nutrition security amidst evolving global challenges. The objectives of this study were: to investigate the effect of different levels of OFSP flour with and without shredded coconut on the physical, microbiological, nutritional and sensory properties of buttermilk biscuits. The hypotheses were: Ho: There is no effect of different levels of OFSP flour and shredded coconut on the physical, microbiological, nutritional and sensory properties on buttermilk biscuits at ∝ = 0.05 and Ha: There is an effect of different levels of OFSP flour and shredded coconut on the physical, microbiological, nutritional and sensory properties on buttermilk biscuits at ∝ = 0.05.MethodsOFSP flour was produced and combined with wheat flour at different ratios and infused with desiccated shredded coconut to produce six formulations of buttermilk biscuits: 100% wheat flour + 5% coconut (control 1), 100% wheat flour (control 2), 70% wheat flour + 30% OFSP flour + 5% coconut, 70% wheat flour + 30% OFSP flour, 50% wheat flour + 50% OFSP flour + 5% coconut and 50% wheat flour + 50% OFSP flour. The study followed a randomised 3 × 2 factorial design where each treatment was replicated four times giving 24 treatments. Physical, nutritional, sensory, microbiological and shelf-life analyses were determined for each buttermilk biscuit treatment.ResultsThe study’s findings revealed that buttermilk biscuits formulated with 30% OFSP flour received the highest (p < 0.05) sensory evaluation scores for the majority of attributes and overall acceptability while the 100% wheat flour formulations received the lowest scores according to the 9-point hedonic scale. Notably, the inclusion of shredded coconut did not improve sensory attributes or overall acceptance of the buttermilk biscuits. The OFSP flour buttermilk biscuits contained protein, fat, fibre, moisture and ash. The 100% wheat flour treatments contained significantly higher levels of proteins and moisture than the OFSP flour buttermilk biscuits. The colour L* of the OFSP flour treatments were significantly lower than the 100% wheat flour treatments. There were no significant changes in spread-ratio, diameter and thickness of the buttermilk biscuits during storage. Furthermore, the microbiological quality was maintained as no growth of bacteria, yeasts and molds were observed.DiscussionThe OFSP flour with and without desiccated coconut produced acceptable buttermilk biscuits with less reliant on wheat flour. It is noteworthy that the protein content of the OFSP flour buttermilk biscuits was at an acceptable level even though it was lower than that in 100% wheat flour buttermilk biscuits. Food safety was maintained throughout storage which is crucial in the elimination of food borne diseases. The use of different baking parameters can be used for future studies to assess the effect of temperature on the quality of buttermilk biscuits.

Genetic characterization and mapping of the shell-strength trait in peanut.

Shell strength is an important trait in peanuts that impacts shell breakage and yield. Despite its significance, the genetic basis of shell strength in peanuts remains largely unknown, and the current methods for rating this trait are qualitative and subjective. This study aimed to investigate the genetics of shell strength using a segregating recombinant-inbred-line (RIL) population derived from the hard-shelled cultivar 'Hanoch' and the soft-shelled cultivar 'Harari'. Initially, a quantitative method was developed using a texture analyzer, focusing on the proximal part of isolated shells with a P/5 punching probe. This method revealed significant differences between Hanoch and Harari. Shell strength was then measured in 235 RILs across two distinct environments, revealing a normal distribution with some RILs exhibiting shell strength values beyond those of the parental lines, indicating transgressive segregation. Analysis of variance indicated significant effects for the RILs, with no effects of block or year, and a broad-sense heritability estimate of 0.675, indicating a substantial genetic component. Using an existing genetic map, we identified three QTLs for shell strength, with one major QTL (qSSB02) explaining 18.7% of the phenotypic variation. The allelic status of qSSB02 corresponded significantly with cultivar designation for in-shell or shelled types over four decades of Israeli peanut breeding. Physical and compositional analyses revealed that Hanoch has a higher shell density than Harari, rather than any difference in shell thickness, and is associated with increased levels of lignin, cellulose, and crude fiber. These findings provide valuable insights into the genetic and compositional factors that influence shell strength in peanut, laying a foundation for marker-assisted selection in breeding programs focused on improving pod hardness in peanuts.

Integrated fracture analysis for improved oil recovery in the reefal limestones of Soğucak formation, Northwest Thrace Basin, Türkiye

Natural fractures play a crucial role in both exploration and development phases in oil and gas industry, as their network and orientation significantly affect flow and recovery strategies. This study highlights the importance of identifying opening-mode fracture systems within a mature Deveçatağı oil field that has been actively producing for nearly half a century. In order to investigate the most effective rock physics parameter to locate oil saturated zones in the field, this study applies detailed rock physics analysis and 2D forward modeling to pinpoint the principal factors affecting production in the Deveçatağı oil field, addressing the challenge posed by the limited shear wave wireline data acquired from only one well within this highly heterogeneous area. Analysis show that acoustic impedance is a crucial elastic property for detecting oil-saturated zones especially in areas with natural fractures. This study successfully integrates drilling-induced fracture (DIF) data, ant tracking maps, and seismic inversion outputs to understand on the issues leading to dry wells and advances in developing more effective exploration and recovery methods in fractured reservoirs. After almost 50 years of operational activities, well stimulation processes, and natural fractures that are present in this field, understanding oil drainage mechanisms in such environments is complex, emphasizing the need for comprehensive analysis to optimize production strategies.

A phase I study assessing the safety and tolerability of SPL84, an inhaled antisense oligonucleotide for treatment of cystic fibrosis patients with the 3849 +10kb C->T

BackgroundAntisense Oligonucleotides (ASOs) are small synthetic nucleic acid molecules able to bind specific sequences within target Ribonucleic Acid (RNA) molecules. SPL84 is an ASO drug developed for treatment of cystic fibrosis (CF) patients carrying the 3849 + 10 kb C->T Cystic Fibrosis Transmembrane Conductance Regulator (CFTR) splicing mutation. The 3849 + 10 kb C->T variant leads to inclusion of cryptic exon harboring stop codon leading to the production of truncated non-functional CFTR proteins. in vitro, SPL84 treatment results in splicing modulation, which leads to an increase of correctly spliced CFTR RNA and higher levels of functional CFTR proteins. MethodsSPL84 was tested in a blinded, placebo-controlled phase 1 study in thirty two (32) healthy volunteers (HVs), each received a single dose of either SPL84 or placebo by inhalation. A total of 8 participants were randomized to each of the 4 escalating cohorts in a 3:1 ratio (active: placebo). Safety and tolerability were evaluated by monitoring adverse events (AEs), vital signs, physical exam findings, spirometry, electrocardiograms (ECG), and analyses of safety laboratories. Blood samples were obtained periodically over 24 h for measurement of systemic exposure. ResultsThere were no significant changes from baseline in vital signs, clinical laboratory values, ECG, physical examination, or pulmonary function. There were no Serious Adverse Events (SAEs) in the study, and there were no significant adverse events. The systemic exposure to SPL84 was low and tended to be dose dependent. The exposure, expressed in terms of area under the curve to infinity (AUCinf), at the no observed adverse effect level (NOAEL) in 9-week toxicological mice study was 7.51 µg/ml*hrs, which is ∼20 times higher than the exposure at the 160 mg dose (444 ng/ml*hrs). ConclusionsSPL84 was safe and well-tolerated when administered as a single inhaled dose to HVs at doses up to 160 mg, with minimal systemic exposure. There were no safety issues observed, no SAEs, no significant related AEs, and, importantly, no significant effect on pulmonary function. The successful completion of the study enabled the initiation of multi-dosing of CF patients in a phase 2 clinical study.

Design, Synthesis, QSAR Studies, and Molecular Modeling of Some Novel Bis Methyl 2-[3-(benzo[d]thiazol-2-yl)-2-terephthaloyl-bis-4-oxo-thiazolidin- 5-ylidene]acetates and Screening of their Antioxidant and Enzyme Inhibition Properties.

Benzothiazolamine-based bisthiourea precursors were prepared in good yields. These bisthiourea derivatives were cyclized into symmetrical Bis Methyl 2-[3-(benzothiazol- 2-yl)-2-terephthaloyl-bis-4-oxo-thiazolidin-5-ylidene]acetates, by their condensation with (DMAD) dimethyl but-2-meditate in the presence of dry methanol. All these compounds were evaluated for their biological applications. Antioxidant activities were performed by adopting a DPPH radical assay, and an in vitro enzyme inhibition assay was performed to investigate their enzyme inhibitory potential against butyrylcholinesterase (BChE) and acetylcholinesterase (AChE). Molecular modeling and QSAR studies were performed to monitor the binding propensity of imidathiazolidinone derivatives with enzymes and DNA. Also, electronic and steric descriptors were calculated to determine the effect of structure on the activity of imidathiazolidinone derivatives. The characterization of all the synthesized compounds was done by their physical data, FT-IR, NMR and elemental analysis.

A rare prenylated isoflavone-quinone from the roots of Flemingia philippinensis

In order to make more rational use of Flemingia Philippinensis, a systematic separation from the roots of F. philippinensis was performed in the current study. The investigation of chemical constituents resulted in the isolation of a rare prenylated isoflavone-quinone, fleminquinone A (1), together with four known analogues (2–5). Their structures were established by extensive physical and spectroscopic data analysis. Anti-inflammatory activities of the isolated compounds were evaluated in lipopolysaccharide induced mouse mononuclear macrophage leukemia cells RAW 264.7 model. Compound 1 exhibited significant inhibitory effects on LPS-induced NO production and COX-2. Compound 1 also significantly affected the levels of inflammatory cytokines.

Relativistic Modeling of Charged Anisotropic Stars in a Buchdahl Spacetime

In this paper, we studied the behavior of relativistic objects with charged anisotropic matter distribution with a linear equation of state considering a metric potential proposed for Buchdahl (1959). The new solutions to the Einstein-Maxwell system of equations are found in term of elementary functions. A physical analysis of electromagnetic field indicates that is regular in the origin and well behaved. The new obtained models satisfy all physical requirements of a physically reasonable stellar object. The models are consistent with the upper limit on the mass of compact stars for PSR J1823-3021G, PSR J1748- 2446an and PSR J1518+4904.

Nephro- and Cardiotoxic Effects of Etoricoxib: Insights into Arachidonic Acid Metabolism and Beta-Adrenergic Receptor Expression in Experimental Mice

Background: Etoricoxib is a widely used anti-inflammatory drug, but its safety profile concerning cardiovascular and renal health remains inadequately explored. This study aimed to assess the nephro- and cardiotoxic effects of etoricoxib in a murine model, with a focus on its impact on arachidonic acid-metabolizing enzymes and beta-adrenergic receptors associated with drug-induced toxicity. Methods: Thirty-five BALB/C mice were randomly assigned to five groups: control, low-dose etoricoxib, high-dose etoricoxib, low-dose celecoxib, and high-dose celecoxib (a well-known nephro- and cardiotoxic NSAID). The treatments were administered for 28 days, after which hearts and kidneys were excised for physical and histopathological analysis, and the expression of arachidonic acid-metabolizing enzymes (cytochrome P450s, lipoxygenases, cyclooxygenases) and beta-1 adrenergic receptor (adrb1) and angiotensin-converting enzyme (ace2) genes were quantified using quantitative reverse transcription PCR (qRT-PCR). Results: Etoricoxib administration resulted in dose-dependent nephro- and cardiotoxic effects. Renal histology revealed glomerular atrophy or hypertrophy and significant damage to the proximal and distal convoluted tubules, including epithelial flattening, cytoplasmic vacuolation, and luminal widening. Cardiac analysis showed disorganized muscle fibers and hyaline degeneration. These changes were associated with altered gene expression: the downregulation of cox2, cyp1a1, and cyp2c29 in the kidneys and the upregulation of cyp4a12, cox2, and adrb1, along with the downregulation of cyp2c29 and ace2 in the heart. Conclusions: Etoricoxib induces nephro- and cardiotoxicity, marked by alterations in arachidonic acid metabolism and beta-adrenergic signaling pathways. The drug affects the expression of arachidonic acid-metabolizing enzymes and adrb1 in the heart while downregulating cox2 and other related enzymes in the kidneys. These findings underscore the need for caution when prescribing etoricoxib, particularly in patients with pre-existing renal or cardiac conditions.

Analysis of the mechanical properties and micro-reinforcement mechanisms of loose accumulated sandy soil improved with polyvinyl alcohol and sisal fiber

As one of the world’s most fragile and sensitive ecological regions, Xizang risks significant environmental damage from using traditional materials, including cement and lime, to improve and reinforce loose accumulated sandy soil slopes. To address this issue, this study utilized a low-concentration biodegradable polyvinyl alcohol (PVA) solution combined with sisal fibers (SFs) to stabilize loose accumulated sand in southeastern Xizang. A series of physical, mechanical, and microscopic analyses was conducted to evaluate the properties of the treated sand. The results indicated the following. 1) The stress-strain curves of the improved samples exhibited an elastic-plastic relationship. Failure was observed in two stages. At a strain of 3% or less, the samples demonstrated elastic deformation with a linear increase in stress, whereas the deviator stress increased rapidly and linearly with an increase in axial strain. Once the strain exceeded 3%, the deformation became plastic with a nonlinear increase in the stress-strain relationship, and the growth rate of the deviator stress gradually decreased and leveled off. 2) Under varying confining pressure conditions, the relationship curve between the maximum (σ1-σ3)max∼σ3 for both untreated loose accumulated sandy soil and soil improved with the PVA solution, and the sisal fiber was approximately linear. 3) The SFs created a skeletal-like network that encased the soil particles, and the hydroxyl functional groups in the PVA molecules bonded with both the soil particles and the fiber surface, thereby enhancing the interfacial properties. This interaction resulted in a tighter connection between the soil particles and SFs, which improved the stability of the structure. 4) The incorporation of a PVA solution and SFs significantly enhanced the mechanical strength and deformation resistance of the loose accumulated sandy soil. The optimal ratio for the improved soil was SP = 3% and SL = 15 mm, which increased the cohesion from 24.54 kPa in untreated loose accumulated sandy soil to 196.03 kPa. These findings could be applied in engineering practices to improve and reinforce loose accumulated sandy soil slopes in southeastern Xizang and provide a theoretical basis for such applications.

Characterization of Natural Gas Hydrate Constrained by Well and Seismic Data in Qiongdongnan Basin

This study investigates the natural gas hydrates within the Qiongdongnan Basin by integrating well-log and seismic data. Through pre-stack inversion and rock physics analysis, key parameters such as P-wave and S-wave impedances were utilized to distinguish hydrate-bearing formations from other geological bodies. A low-frequency model was constructed using the Inverse Distance Weighting (IDW) algorithm to improve the precision of parameter inversion. This study employs a multi-constraint inversion strategy, incorporating hard constraints from multiple wells and soft constraints from geological frameworks, ensuring reliable inversion results. Findings indicate that hydrate reservoirs are characterized by increased wave velocity and density due to hydrate accumulation, providing insights into the spatial distribution and characteristics of hydrates. This research enhances the understanding of hydrate reservoirs and offers valuable data for exploration in the Qiongdongnan Basin.

Construction of a generalized mathematical model and fast calculations of plane-parallel rotating magnetic fields in process reactors with longitudinal currents of cylindrical inductors on a graphical calculator

The object of research is a quasi-stationary rotating magnetic field (RMF) generated by cylindrical inductors with longitudinal windings in the working space of process reactors, in particular reactors designed to work with magnetic particles (MP). The RMF theory in the working space of reactors has not yet been sufficiently developed, which hinders the widespread introduction of the considered, rather complex technologies into practice. The RMF of a specific reactor can be calculated accurately and completely using modern programs based on the finite element method, but it does not replace the general theory and theoretical analysis. In the literature, special cases of circular and elliptical plane-parallel RMF in reactors of the type under consideration have been studied, however, analytical formulas for a plane-parallel RMF for the general case of m-phase cylindrical inductors of external and internal design with symmetrical longitudinal windings are not presented. In this paper, a mathematical model is constructed and generalized analytical formulas for magnetic induction are obtained, linking the characteristics of a plane-parallel RMF in the working space of reactors at idle speed with the main parameters of external and internal cylindrical inductors with an m-phase symmetric longitudinal winding. A physical analysis is carried out and the adequacy of the model is confirmed. Using the proposed formulas and a free, easy-to-use Desmos graphical calculator, quick trial calculations and analysis of RMF in several reactors with two-pole external inductors and various windings for three phases (for 6 and 42 slots) and for six phases (12 slots) are carried out. The calculation results are consistent with experimental and literary data. New analytical formulas, as well as the demonstrated methods of quick evaluation calculations, analysis and experimental studies are recommended for practical implementation in the research, development and operation of reactors of this type. To carry out the calculations, it is enough to have a laptop or smartphone connected to the Internet, the time costs are insignificant. The results of the work will be useful to technologists, engineers and developers of both the reactors of the type under consideration and other devices with a similar purpose with an RMF.

Exploring the Soil Structure Analysis of a Subtropical Watershed by Introducing a Blanket Physico‐Hydraulic Health Index

ABSTRACTMultiple disturbed and undisturbed soil samples were collected to assess the soil structure health in support of water use and management in a subtropical watershed, which is composed of shallow Entisols, near to Canguçu, RS state—Brazil. Various physico‐hydraulic properties related to soil structure, such as bulk density, total, micro and macroporosity, saturated hydraulic conductivity, organic carbon, soil water retention curve (SWRC), and the ranges of plant available water (PAWC) and drainable porosity (DP) were measured to be analyzed. The hydraulic‐energy indices of soil aeration and water retention were determined by integrating the areas under SWRC. Combining these properties with the contents of sand and clay, a unique blanket soil physico‐hydraulic health index (BSPHI) was formulated and applied to investigate the impact of land use and management on the soils of the Ellert Creek Watershed (ECW), thereby supporting soil physical health analysis and, consequently, the analysis of water and human health. The favorable outcomes found in the ECW soils under annual crops indicated good root aeration in the surface layer due to the balance between DP and PAWC. The BSPHI results showed that only about 19% of the areas exhibited unhealthy physical health. The soil structure in pasture areas of ECW was not significantly impacted by the extensive cattle grazing, whereas lands under native forest served as a control for the natural soil quality status. The BSPHI successfully captured small changes in soil structure, regardless of land use and management, highlighting its potential as a promising tool for evaluating soil health by assessing the soil physical quality.

Geoenvironmental and geophysical methods applied to identify natural attenuation process on a complex hydrogeological environment contaminated by hydrocarbons

Environmental contamination found in urban areas generally has a chemical composition that favors the generation of a variety of physical, chemical and biological processes that differ from natural soil parameters. Thus, understanding natural attenuation processes in tropical environments is still a challenge, as is understanding how biogeochemical processes can influence and modify natural soil characteristics. The study aimed to apply methods that are not commonly used in investigations of contaminated areas, in order to assess the applicability of non-invasive methodology for detailed stratigraphic characterization and biogeochemical changes resulting from contamination by hydrocarbons in a complex hydrogeological environment site. To date, few studies have presented results obtained using non-invasive techniques to understand biochemical processes. The research was based on the interpretation of results obtained by high-resolution physical environment characterization techniques (such as gamma geophysical profiling and electrical conductivity surveys) and chemical analysis of groundwater. The data was interpreted to obtain a detailed characterization of the study area and evidence of the occurrence of natural attenuation of creosote contamination. The results indicated that the combination of geoenvironmental and geophysical methods is an interesting alternative for obtaining data and understanding the mineralogical and stratigraphic variation of the contaminated area. The physical parameters variations obtained by the methods suggested the presence of local geochemical alterations resulting from natural processes of attenuation of contamination by aliphatic and aromatic hydrocarbons in a tropical environment. The natural attenuation processes were confirmed through groundwater samples, biological analysis and metagenomic classification.