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Starch is a promising polymer for creating novel microparticulate systems with superior biocompatibility and controlled drug delivery capabilities. In this study, we synthesized polyethylene glycol (PEG)-modified starch microparticles and encapsulated folic acid using a solvent-mediated acid-base precipitation method with magnetic stirring, which is a simple and effective method. To evaluate particle degradation, we simulated physiological conditions by employing an enzymatic degradation approach. Our results with FTIR and SEM confirmed the successful synthesis of starch–PEG microparticles encapsulating folic acid. The average size of starch microparticles encapsulating folic acid was 4.97 μm and increased to 6.01 μm upon modification with PEG. The microparticles were first exposed to amylase at pH 6.7 and pepsin at pH 1.5 at different incubation times at physiological temperature with shaking. Post-degradation analysis revealed changes in particle size and morphology, indicating effective enzymatic degradation. FTIR spectroscopy was used to assess the chemical composition before and after degradation. The initial FTIR spectra displayed characteristic peaks of starch, PEG, and folic acid, which showed decreased intensities after enzymatic degradation, suggesting alterations in chemical composition. These findings demonstrate the ongoing development of starch–PEG microparticles for controlled drug delivery and other biomedical applications and provide the basis for further exploration of PEG–starch as a versatile biomaterial for encapsulating bioactive compounds. [ABSTRACT FROM AUTHOR]

This work studies the multiple sources of impacts and disturbances in the Laja River (Central Chile) and evaluates the changes in water and sediment flows and planimetric geomorphic changes. The disturbances sources correspond to hydroelectric plants, water withdrawals for irrigation and the sustained decrease trend in rainfall in the basin. The changes in the plan‐view shape of the river reach were quantified using remote sensing techniques, through a supervised classification of Landsat 5 TM and 8 OLI satellite images, identified Water (W), Islands and Riverine Vegetation (IRV) and Bars and Banks Without Vegetation (BBWV), obtained a Kappa index>0,83 for a period of 15 years (2006–2021). Compared with historical records, the period of analysis shows a decrease in annual rainfall by 17.5%. In addition, water withdrawals for irrigation have contributed to a 64% decrease in monthly stream discharge during the dry season. As a consequence of the decrease in annual rainfall and water withdrawals for irrigation, the sediment transport capacity has also decreased by 10.5%. The changes in morphological driving variables (stream flows and sediment transport regimes) have manifested themselves in morphological changes, where it was possible to establish that a change in the channel form occurred in the last 15 years, going from a river with a single channel to a braided one. An important vegetation establishment has accompanied this morphological change on both riverbanks and the central bars. The colonizing vegetation corresponds to fast‐growing non‐native species (Salix spp., Populus spp. and Alnus spp). A stabilization of the channel form is expected, consolidating itself as a braided section with alternating vegetated bars. [ABSTRACT FROM AUTHOR]

Hyadesimyia clausa Bigot is a morphologically striking tachinid that inhabits the Sub‐Antarctic Ecoregion of the Magallanes Region in Chile and Tierra del Fuego province in Argentina. Much of the distributional information about this species is restricted to the Cape Horn islands, which have extreme environmental conditions, but the species' natural history, range limits, and habitat use have never been described or confirmed. Our goals were to describe the distributional limits of this sub‐Antarctic fly with the help of citizen science and use this information type to describe this tachinid's habitat use and potential biological interactions with nonvascular and vascular flora. We found that citizen science significantly increased our understanding of the extent of occurrence, expanding the known distributional range by 195 km to the north and 153 km to the west. On the contrary, the values for the area of occupancy were not significant, but the occupancy overlap between different records was very low. We confirmed that H. clausa's habitat uses peatlands and although we have not provided evidence of pollination or movement of spores, we hypothesized, that the walking activity of H. clausa could help move sperm from mosses and pollen from the flowers of vascular plants, so they could act as potential pollinators. Citizen science can reduce and eliminate some scientific knowledge shortfalls and propose new ecological questions that could increase our knowledge of extreme ecosystems. [ABSTRACT FROM AUTHOR]

The energy load requirements demanded to the network operator of the department of Huila are supplied according to corporate guidelines; but under the responsibility of the user, despite his technical-legal ignorance and the absence or inadequate technical advice, with the consequent irregularities in connections and, in fact, with economic and financial affectations. The analysis of this problem, with an exploratory scope, is approached with a quantitative and qualitative focus, which is deepened by means of the multiple case study strategy. In this way, an energy requirements guide and a tool, applicable during the phase prior to the load requisition, which allow to dynamize and improve the decision making process from the project management and the private investor. [ABSTRACT FROM AUTHOR]

ABSTRACT Introduction: The main causative agent of spinal infections is Mycobacterium Tuberculosis, followed by saprophytes of the skin. The most affected segment is the lumbar, followed by the thoracic. Objective: Case report. Results: A previously healthy 40-year-old man with posterior cervical pain and myelopathy was referred to our spine service for vertebral destruction syndrome in C3-C4 and altered carbohydrate metabolism. Microdiscectomy and abscess drainage were performed and a biopsy was taken for definitive diagnosis. Multiresistant Serratia Marcescens was isolated in the culture. Both the myelopathy and carbohydrate intolerance were resolved as the infection was resolved. Conclusion: The significance of this case lies in the infective presentation of the S. Marcescens in an immunocompetent person, since it is mainly an opportunistic microorganism, and in the atypical location. The most commonly isolated pathogen is Mycobacterium Tuberculosis, followed by Staphylococcus aureus. Identification of the causative agent is essential to the initiation of antibiotic therapy. Therefore, microbiological isolation plays a fundamental role in the treatment, recovery and quality of life of the patient. Level of evidence V; Case report.