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  • Miniatura
    Item type: Artículo ,
    Morphofunctional indices and ontogeny of long bones of the limbs in the frogs
    (Wiley-liss, div John Wiley & Sons Inc., 2026-10)
    Soliz, Monica Carina
    ;
    Tulli, María José
    Anuran limbs offer a valuable model for exploring how selective pressures, developmental constraints, and morphological evolution interact. While previous research has largely focused on total limb length, little is known about ontogenetic changes in the proportions of individual limb bones. This study introduces a novel approach using morphofunctional indices to investigate the functional roles of frog limbs, linking morphology to habitat use and locomotion. We present morphological and ontogenetic data from anurans in northwestern Argentina, emphasizing functionally relevant bone indices. Measurements were taken of 18 long bone dimensions (humerus, radioulna, femur, tibiofibula, tarsals) across 79 specimens at metamorphic, juvenile, and adult stages. Eight morphofunctional indices were calculated, including five newly proposed ones. Indices such as radioulna robustness, groove position, femur and tibiofibula robustness, and tarsal fusion differed among ecological and locomotor groups. Terrestrial hopper-walkers such as Rhinella arenarum and Rhinella spinulosa have more robust hind limb bones and shorter, less-fused tarsals than jumpers like Boana riojana. These traits may be functionally associated with short-distance jumping and shock absorption. We also observed a slenderness–robustness gradient across species, reflecting locomotor strategies. Stylopodial elements show negative allometry, while zeugopodial elements exhibit positive allometry, indicating increased precision and flexibility in limb function throughout development.
  • Miniatura
    Item type: Artículo ,
    Theoretical study of CH4 intercalation in sI clathrate hydrates for energy storage
    (Elsevier Science, 2026-10)
    Juan, Julián
    ;
    Longone, Pablo Jesus
    ;
    Marchetti, Jorge Mario
    ;
    Pronsato, Maria Estela
    ;
    Ramirez Pastor, Antonio Jose
    The sI methane clathrate hydrate system has been identified as a potential candidate for application as an energy storage material. Previous studies have utilized Monte Carlo (MC) simulations of this system, assuming it to be a two-dimensional (2D) lattice gas. Density Functional Theory (DFT) studies can be performed to enhance our understanding of the interaction of guest species, such as methane in different concentrations, and to facilitate comparison with MC simulations and the acquisition of different properties. DFT simulations were conducted to study the stability of methane in the sI clathrate hydrate, finding that one molecule per cavity in the system is the most stable configuration found, which is in agreement with MC. The configurations obtained validate previous studies from our group that model methane clathrate hydrates using a 2D lattice gas. Novel electronic density of states, bond order and charge density difference analysis with and without methane are performed. The intercalated system shows that it has van der Waals interactions, and there is a lower bond strength for the intercalated material, which could allow diffusion. The material has favorable interaction energy and stability, so further experimental and theoretical studies are suggested.
  • Miniatura
    Item type: Evento ,
    A novel optimization model for the simultaneous batching, production and distribution scheduling in process industries
    (Asociación Argentina de Matemática Aplicada, Computacional e Industrial, 2023)
    Tibaldo, Aldana
    ;
    Fumero, Yanina
    ;
    Montagna, Jorge Marcelo
    Traditionally, the short-term production and distribution activities have been addressed with a decoupled and sequential methodology. Although this approach simplifies the problem, there are several environments in which this methodology generates inefficiencies. Consequently integrated management of these activities is essential. This paper presents a novel mixed-integer linear optimization model to manage production and distribution decisions simultaneously at minimum operating cost. An effective strategy is proposed where all feasible routes that vehicles can travel are generated beforehand. This approach is very valuable mainly for two reasons: infeasible routes are not considered in the problem formulation (reduction of the search space) and several important decisions are made simultaneously when a route is selected, such as the allocation and sequencing of the customers visited in each route. The performance of the proposed model is compared against a first approach that, unlike the current formulation, presents difficulties in large problems.
  • Miniatura
    Item type: Artículo ,
    Integrated Transmitted Light Microscope (TLM), Confocal Laser Scanning Microscope (CLSM), and Scanning Electron Microscope (SEM) studies reaffirm the long-debated taxonomic status of Parasaccites Bharadwaj et Srivastava 1964 as a junior synonym of Cannanoropollis Potonié et Sah 1960
    (Schweizerbart Science Publisher, 2026-03)
    Mishra, Ayushi
    ;
    Kavali, Pauline Sabina
    ;
    Di Pasquo Lartigue, Maria
    ;
    Saha, Omnath
    Despite several workers re-emphasizing the taxonomic status of the Pennsylvanian–Permian (late Paleozoic) cordaitalean morphogenus Parasaccites as a junior synonym of Cannanoropollis, Parasaccites is still in use, especially in India. Therefore, to resolve this discrepancy and re-affirm if Parasaccites merits a generic status or must be considered as a junior synonym of Cannanoropollis as claimed, we took up this work for a detailed study comprising of an extensive review of the older systematic works, re-examination of illustrated specimens and slides of available holotypes/paratypes of both the genera under Transmitted Light Microscope (TLM), Confocal Laser Scanning Microscope (CLSM), and Scanning Electron Microscope (SEM). They were also compared with specimens of palynological materials collected from the Koel-Damodar and Wardha-Godavari Basins in India and South American Basins (Bolivia, Argentina, Brazil, and Uruguay). The materials analysed correspond to different stages of the full-acid treatment, including oxidation, and were mounted on slides to observe their effects on grain morphology. The morphological features re-examined were amb, corpus, nature of the saccus, and diameter, all of which showed no apparent differences between the two genera. The nature of the zone of attachment, which was considered the main distinguishing character despite its difficulty to interpret, especially in poorly preserved or oxidized specimens, was not mentioned in the original diagnosis of Canannoropollis. This feature was mentioned in later works and observed in our present study, in which well-preserved specimens displayed different zones of saccus attachment, ranging from subequatorial proximal and distal attachment to proximally equatorial–subequatorial to distally subequatorial attachment, sometimes with a diffuse transition. Therefore, we emended the original diagnosis of Cannanoropollis to incorporate the possible attachment zones. The remaining features of Parasaccites overlap with those of Canannoropollis and thus do not warrant a generic status for it. Hence, this work reaffirms that Parasaccites is a junior synonym of Canannoropollis, and by the nomenclatural rule of priority, its further use should be avoided. The remaining species erected under Parasaccites have been synonymized with the convalidated species of Cannanoropollis based on their original or emended diagnoses, viz., C. janakii, C. densus, and C. triangularis. Meanwhile, some bilateral species erected under Parasaccites have been transferred to other genera, such as Caheniasaccites and Potonieisporites, because they differ from Cannanoropollis, which bears a radial amb.
  • Miniatura
    Item type: Artículo ,
    Mechanical behaviour of loess soil stabilised with natural biopolymers
    (Emerald Publishers, 2026-04)
    del Frade Albenga, Federica
    ;
    Francisca, Franco Matias
    Collapsible loess soils are a major geotechnical concern due to their high sensitivity to moisture and structural instability upon wetting. This study evaluates the potential of two natural biopolymers, xanthan gum (XG) and guar gum (GG), as sustainable soil stabilisers aimed at improving the mechanical behaviour of compacted loess under variable moisture and curing conditions. Compaction and unconfined compression tests were conducted on soil-biopolymer mixtures with 1% and 2% content, cured for up to 56 days. The results show that biopolymers reduce dry unit weight and increase optimum moisture content, with XG yielding unconfined compressive strengths up to 466 kPa. GG, although less effective in strength, led to greater stiffness gains under specific conditions. Scanning electron microscopy revealed distinct microstructural improvements, including gel bonding and matrix densification. These findings support the technical feasibility of using biopolymers for environmentally friendly ground improvement in collapsible soils, particularly in arid and semi-arid regions where moisture variation is a critical design factor.