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Little is known about the role of horse flies in potential pathogen transmission in Chile. This study provides evidence of the molecular detection of microorganisms in southern Chile. In the present study, adult Osca lata horse flies were trapped from Punucapa (39°45'06"S/73°16'08"W, Región de Los Ríos) and Puyehue (40°39'10"S/72°10'57"W, Región de Los Lagos), Chile. Among the 95 samples analyzed by PCR using specific primers, microorganisms were detected in 23.2% (n = 22) of the samples. Rickettsia spp. DNA was detected in 15.8% (n = 15) of the samples, Trypanosomatidae DNA in 5.3% (n = 5) of the samples, and filarial DNA in 2.1% (n = 2) of the samples. This study found that horse flies in the region are capable of carrying a variety of both parasites and endosymbionts. Further research is needed to understand the specific impact of horse flies as mechanical or biological vectors and develop effective control measures to prevent the spread of any microorganisms associated with disease. Author summary: Horse flies are well-recognized mechanical vectors of pathogens in humans and domestic animals. Our study on the black horse fly, Osca lata, an abundant species in south-central Chile, sought to explore whether this hematophagous species could act as a vector of microorganisms that can affect domestic animal, and even human, health. We used molecular techniques to detect evidence of three types of microorganisms in samples analyzed from southern Chile. These results indicate that this fly species has the potential to harbor parasitic agents. Further studies are necessary to understand the specific role of horse flies as mechanical vectors and their potential impact on disease transmission in different regions and animal populations. [ABSTRACT FROM AUTHOR]

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]

Polylactic acid (PLA) is a bioresorbable and biodegradable polymer extensively used in various biomedical and engineering applications. In this study, we investigated the mass loss and thermal properties of PLA-multi-walled carbon nanotube (MWCNT) composites under simulated physiological conditions. The composites were prepared by melting PLA with 0.1, 0.5, 1.0, and 5.0 wt% MWCNTs using an ultrasonic agitator, and FTIR analysis confirmed composite formation. Subsequently, the composites were subjected to hydrolysis under simulated physiological conditions (pH 7.4 and 37 °C) for up to 60 days. The results revealed that the mass loss of the composites decreased with increasing MWCNT content, suggesting that the presence of MWCNTs decelerated the hydrolysis process. On day 58, the mass loss of pure PLA was 12.5%, decreasing to 8.34% with 0.1% MWCNT, 5.94% with 0.5% MWCNT, 4.59% with 1% MWCNT, and 3.54% with 5.0% MWCNT. This study offers valuable insights into the behavior of PLA-MWCNT composites under physiologically simulated conditions, facilitating the development of new polymer composites with enhanced thermal stability and degradation resistance for biomedical applications. [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]

Climate change, competent vectors, and reservoir animals are the main factors for developing vector-borne zoonotic diseases. These diseases encompass a significant and widespread category of pathogens (e.g., viruses, bacteria, protozoa, and helminths) transmitted by blood-feeding arthropods, including ticks, fleas, lice, triatomines, mosquitoes, sandflies, and blackflies. In Chile, several studies have explored the role of dogs as reservoirs of vector-borne pathogens; however, there is a lack of research investigating the presence of pathogens in arthropods. Specifically, within the order Diptera, limited knowledge exists regarding their roles as carriers of pathogens. This study aimed to examine the presence of zoonotic filarial nematodes in mosquitoes and dogs within a previously unstudied semirural area of Central Chile. Two hundred samples of dog blood and seven hundred and twenty-four mosquitoes were collected during 2021-2022 and studied for filarial nematodes by PCR. The prevalence of microfilaremic dogs detected by Knott's test was 7.5%, with Acanthocheilonema reconditum being the only species identified. Aedes (Ochlerotatus) albifasciatus was the most abundant mosquito species collected, and 15 out of 65 pools were positive for filarial nematodes. Among these pools, 13 tested positive for Acanthocheilonema reconditum, and two tested positive for Setaria equina through PCR. Additionally, five Culex pipiens specimens were positive for Acanthocheilonema reconditum. Despite the absence of zoonotic filarial species, these findings underscore the significance of monitoring pathogens in mosquitoes and animal hosts and continued research into the dynamics of vector-borne diseases, particularly in unexplored regions. [ABSTRACT FROM AUTHOR]

Geometric morphometrics was used to determine whether geographic isolation could explain differences in wing size and shape between and within continental (27°S to 41°S) and insular (Rapa Nui) populations of Culex pipiens s.s. Linnaeus and their biotypes (f. pipiens and f. molestus). Molecular protocols based on polymorphisms in the second intron of nuclear locus ace-2 (acetylcholinesterase-2) were used to differentiate Cx. pipiens s.s. from Cx. quinquefasciatus Say, and an assay based on polymorphisms in the flanking region of a microsatellite locus (CQ11) was used to identify biotypes. Culex pipiens f. molestus and hybrids shared larval habitats in all continental sites, while Cx. pipiens f. pipiens was found in 5 of the 10 sites. Only biotype molestus was found in Rapa Nui (Easter Island) Pipiens and molestus biotypes occur sympatrically in aboveground locations, and only molestus was found in the underground site (ME). Biotype molestus was dominant in rural locations and preferably anthropophilic. These results agree with the ecological descriptions previously reported for the biotypes of Cx. pipiens s.s. Procrustes ANOVA only showed differences in centroid size between biotypes in females and males and did not show significant differences in wing shape. However, we found significant differences among the geographic areas in the centroid size and wing shape of both females and males. Particularly, the population of Rapa Nui Island had shorter wings than the continental populations. The results highlight the effects of geographic and environmental processes on morphotypes in vector mosquitoes. [ABSTRACT FROM AUTHOR]

Copyright of Dyna is the property of Universidad Nacional de Colombia, Medellin, Facultad de Minas and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Polymeric hydrogel is a promising candidate for drug delivery applications due to its ability to encapsulate and release drugs. Incorporating magnetic particles enables controlled and specific release, providing sustained and targeted delivery. This study aimed to assess the cytotoxicity of the magnetite-polyvinyl alcohol (MPVA) hydrogel, specifically its magnetite content, using 3T3 fibroblast cells. The findings indicate that the MPVA hydrogel with magnetite nanoparticles was compatible with the cells and did not induce cell death. Incorporating magnetite nanoparticles into the PVA hydrogel improved its thermal stability and degradation temperature, disrupting the chain order, decreasing melting behavior, and fractional crystallinity of the hydrogel. The MPVA hydrogel demonstrated a higher gel fraction and crosslink density compared to the PVA hydrogel due to the presence of magnetite nanoparticles. The interaction between PVA and magnetite nanoparticles occurred through non-covalent forces, allowing for reversible interactions and dispersion of the nanoparticles within the PVA matrix. Although the cytotoxicity of the MPVA gel was similar to that of the PVA gel, the viability of fibroblast cells within the MPVA gel varied depending on the concentration. The MPVA hydrogel exhibited stronger attachment and induced irregular changes on the cell surface compared to the PVA hydrogel. Furthermore, the MPVA gel displayed paramagnetic behavior and controllable magnetization, as demonstrated by the hysteresis loop. These magnetic properties make the MPVA gel suitable for potential biomedical applications, including drug delivery, tissue engineering, and magnetic resonance imaging (MRI) contrast agents. [ABSTRACT FROM AUTHOR]

Flavonoids are a diverse group of plant-derived compounds that have been shown to have various health benefits, including anti-inflammatory effects. However, their use in the treatment of inflammatory diseases has been limited due to their low bioavailability. The nanoparticle-mediated delivery of flavonoids has been proposed as a potential solution to this issue, as it allows the sustained release of the flavonoids over time. There are several different nanoparticle systems that have been developed for flavonoid delivery, including polymeric nanoparticles, liposomes, and inorganic nanoparticles. This systematic review aims to evaluate the impact of nanoparticle-mediated delivery of flavonoids on pro-inflammatory cytokine production in various diseases. We analyzed the performance of flavonoid-encapsulated nanoparticles in regulating cytokine production in different in vitro and in vivo studies. To this end, we followed the guidelines of the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) to conduct a comprehensive search of the literature and to assess the quality of the included studies. The results showed that flavonoid-encapsulated nanoparticles significantly downregulated pro-inflammatory cytokines, such as TNF-α, IL-1β, IL-6, and IL-18. In some cases, this effect was significantly greater than that observed with non-encapsulated flavonoids These findings suggest that nanoparticle-mediated delivery of flavonoids may have potential as a therapeutic approach for the treatment of inflammatory diseases. [ABSTRACT FROM AUTHOR]

Due to their potential in numerous interdisciplinary fields, such as drug delivery, hyperthermia, and magnetic resonance imaging, magnetic nanoparticles have attracted widespread attention. In this study, cobalt ferrite nanoparticles are synthesized with varying amounts of iron and cobalt ions, and their cytocompatibility is evaluated before and after surface modification with amino‐silane (AEPTMS). Characterization of the synthesized nanoparticles is performed using scanning electron microscopy, energy‐dispersive X‐ray spectroscopy, X‐ray diffraction, and Fourier transform infrared spectroscopy. In addition, it is observed that a slight reduction in the saturation magnetization of the coated materials. The cytotoxicity of these materials is evaluated using the MTT assay on fibroblast cells. This study focuses on the importance of the interface between the surface of magnetic nanoparticles, their coating, and their interaction with cells. This study presents an innovative approach to enhancing the cytocompatibility of cobalt ferrite nanoparticles through chemical substitution and surface modification with AEPTMS. The key findings demonstrate that the iron and cobalt ion ratio significantly impacts cytotoxicity, with the AEPTMS coating found to increase cell viability. These findings demonstrate the potential of these materials for biomedical applications, highlighting the importance of both the composition and surface coating of magnetic nanoparticles for biomedical applications. [ABSTRACT FROM AUTHOR]

Objectives: Lipid nanoparticles, as a nucleic acid delivery system, have been used as an alternative to treat ocular diseases, since they can cross the ocular barrier and efficiently transfecting nucleic acids to various cells of the eye. The size influences the transfection of genes, biological distribution, diffusion, and cellular uptake. It is therefore important to establish a relationship between size, formulation, and encapsulation percentage. Evidence acquisition: In this review, we used a search strategy to compare studies of nanomedicine systems aimed at eye diseases where the size of the nanoparticles and the efficiency of encapsulation of genetic material are reported based on the criteria of Preferred Reporting Items for Systematic Reviews (PRISMA ScR 2020 guidelines). Results: Out of the initial 5932, 169 studies met the inclusion criteria and were included to form the basis of the analysis. Nanoparticles reported are composed mainly of PEG-modified lipids, cholesterol, and cationic lipids, that in combination with messenger or interference RNA, allow the formulation of a nanoparticle with an encapsulation efficiency greater than 95%. The diseases treated mainly focus on conditions related to the retina and cornea. Certain characteristics of nanoparticles increase encapsulation efficiency, such as the size of the nanoparticle and the charge of the outer layer of the nanoparticle. Conclusion: It is still unknown what characteristics lipid nanoparticles should have to successfully treat human eye illnesses. The in vitro and in vivo investigations covered in this review, however, present encouraging results. To improve encapsulation effectiveness and disease gene silencing, nanoparticle formulation is essential. The most stable nanoparticles are those made mostly of cationic lipids, PEG lipids, and cholesterol, which also effectively encapsulate RNA. The encapsulation efficiency is not only influenced by size, but also by other factors such as methods of preparation. [ABSTRACT FROM AUTHOR]

Colloidal gold particles have been extensively studied for their potential in hyperthermia treatment due to their ability to become excited in the presence of an external laser. However, their light-to-heat efficiency is affected by the physiologic environment. In this study, we aimed to evaluate the ability of gold sphere, rod, and star-shaped colloids to elevate the temperature of blood plasma and breast cancer-simulated fluid under laser stimulation. Additionally, the dependence of optical properties and colloid stability of gold nanostructures with physiological medium, particle shape, and coating was determined. The light-to-heat efficiency of the gold particle is shape-dependent. The light-to-heat conversion efficiency of a star-shaped colloid is 36% higher than that of sphere-shaped colloids. However, the raised temperature of the surrounding medium is the lowest in the star-shaped colloid. When gold nanostructures are exited with a laser stimulation in a physiological fluid, the ions/cations attach to the surface of the gold particles, resulting in colloidal instability, which limits electron oscillation and diminishes the energy generated by the plasmonic excitation. Fluorescein (Fl) and polyethylene glycol (PEG) attached to gold spheres enhances their colloidal stability and light-to-heat efficiency; post-treatment, they remand their optical properties. [ABSTRACT FROM AUTHOR]

Sediment transport controls the evolution of river channels, playing a fundamental role in physical, ecological, and biogeochemical processes across a wide range of spatial and temporal scales on the Earth surface. However, developing predictive transport models from first principles and understanding scale interactions on sediment fluxes remain as formidable research challenges in fluvial systems. Here we simulate the smallest scales of transport using direct numerical simulations (DNS) to explore the dynamics of bed-load and discover how turbulence and grain-scale processes influence transport rates, showing that their interplay gives rise to a critical regime dominated by fluctuations that propagate across scales. These connections are represented using a stochastic differential equation, and a statistical description through a path integral formulation and Feynman diagrams, thus providing a framework that incorporates nonlinear and turbulence effects to model the dynamics of bed-load across scales. [ABSTRACT FROM AUTHOR]

The use of gold nanoparticles as drug delivery systems has received increasing attention due to their unique properties, such as their high stability and biocompatibility. However, gold nanoparticles have a high affinity for proteins, which can result in their rapid clearance from the body and limited drug loading capabilities. To address these limitations, we coated the gold nanoparticles with silica and PEG, which are known to improve the stability of nanoparticles. The synthesis of the nanoparticles was carried out using a reduction method. The nanoparticles' size, morphology, and drug loading capacity were also studied. The SEM images showed a spherical and homogeneous morphology; they also showed that the coatings increased the average size of the nanoparticles. The results of this study provide insight into the potential of gold nanoparticles coated with silica and PEG as drug delivery systems. We used ibuprofen as a model drug and found that the highest drug load occurred in PEG-coated nanoparticles and then in silica-coated nanoparticles, while the uncoated nanoparticles had a lower drug loading capacity. The coatings were found to significantly improve the stability and drug load properties of the nanoparticles, making them promising candidates for further development as targeted and controlled release drug delivery systems. [ABSTRACT FROM AUTHOR]

Copyright of Revista ADM is the property of Asociacion Dental Mexicana and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Four treatment groups were formed: group A, patients with stage II pneumonia who received CP and conventional therapy; group B, patients with stage II pneumonia who received albumin solution and conventional therapy; group C: patients with stage III pneumonia who received convalescent CP and conventional therapy; and group D, patients with stage III pneumonia who received albumin solution and conventional therapy. Convalescent Plasma in Early Discharge Early discharge was considered when patients were discharged up to 15 days after CP/albumin solution infusion; of the patients who received CP, 71.0% were discharged before 15 days, and 29.0% were discharged after 15 days. The mortality of the patients in the CP group was low compared with the mortality of COVID-19 patients in the CEMENAV and HGM centers, which was 55% and 45%, respectively. Keywords: convalescent plasma treatment; COVID-19; neutralizing antibodies; SARS-CoV-2 EN convalescent plasma treatment COVID-19 neutralizing antibodies SARS-CoV-2 1767 13 11/17/22 20221101 NES 221101 1. [Extracted from the article]

Magnetic nanoparticle interfaces have aroused great scientific research interest in the biomedical area since the interaction of cells or biomolecules with nanoparticles is determined by the surface properties. Currently, in medical applications, there is a need to study cell interaction and growth, along with changes in structural or magnetic properties, attributed to nanoparticle coatings. In this study the coercive field changes in NixFe3‐xO4 nanoparticles (x = 0.0, 0.2, 0.4, 0.6, 0.8, and 1.0) driven by partial or total substitution of Fe2+ content by Ni2+, and by aminosilane coating are evaluated. The nanoparticles are synthesized by the coprecipitation method. The inverse spinel structure is confirmed by X‐ray diffraction results and Raman spectra. The aminosilane coating is confirmed by energy‐dispersive X‐ray spectroscopy and Fourier transform infrared spectroscopy. Dynamic light scattering confirms a mean hydrodynamic size of 10 nm. Scanning electron microscopy micrographs of the uncoated and aminosilane‐coated samples show that the particles have a hemispherical shape. The coating increases the coercive field. In addition, uncoated Ni0.2Fe2.8O4 has the highest viability in both MCF7 and HeLa cell lines, and aminosilane coating decreases cell viability. This study contributes to future applications of nanomedicine, such as hyperthermia and drug delivery. [ABSTRACT FROM AUTHOR]

Copyright of Revista Colombiana de Educación is the property of Universidad Pedaggica Nacional and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Mepraia parapatrica is one of the lesser known and less abundant sylvatic triatomine species naturally infected by the protozoan Trypanosoma cruzi, the etiological agent of Chagas disease. M. parapatrica lives in sympatry with T. cruzi-infected rodents, but only birds, reptiles, and marine mammals have been reported as blood-meal sources of this vector species by serology. The distribution range of this kissing bug overlaps with fishers' settlements and tourist areas, and therefore the study of the blood-meal sources of this triatomine species is relevant. Here, we determined the blood-meal sources of M. parapatrica by NGS or standard sequencing from a coastal mainland area and an island in northern Chile, and T. cruzi infection by real-time PCR. The blood-meals of. M parapatrica included 61.3% reptiles, 35.5% mammals (including humans) and 3.2% birds. Feeding on reptiles was more frequent on the mainland, while on the island feeding on mammals was more frequent. The presence of T. cruzi-infected triatomine bugs and humans as part of the diet of M. parapatrica in both areas represents an epidemiological threat and potential risk to the human population visiting or established in these areas. Currently there are no tools to control wild triatomines; these results highlight the potential risk of inhabiting these areas and the necessity of developing information campaigns for the community and surveillance actions. [ABSTRACT FROM AUTHOR]

Pancreatic cancer has one of the highest mortality rates among cancers, and a combination of nab-paclitaxel with gemcitabine remains the cornerstone of first-line therapy. However, major advances are required to achieve improvements in patient outcomes. For this reason, several research groups have proposed supplementing treatment with other therapeutic agents. Ongoing studies are being conducted to find the optimal treatment in a first-line setting. In this work, we used a search strategy to compare studies on the efficacy and safety of nab-paclitaxel with gemcitabine in combination with other therapeutic agents based on the criteria of the Preferred Reporting Items for Systematic Reviews. We found seven studies in different clinical phases that met the inclusion criteria. The seven therapeutic agents were ibrutinib, necuparanib, tarextumab, apatorsen, cisplatin, enzalutamide, and momelotinib. Although these therapeutic agents have different mechanisms of action, and molecular biology studies are still needed, the present review was aimed to answer the following question: which formulations of the nab-paclitaxel/gemcitabine regimen in combination with other therapeutic agents are safest for patients with previously untreated metastatic pancreas ductal adenocarcinoma? The triple regimen is emerging as the first-line option for patients with pancreatic cancer, albeit with some limitations. Thus, further studies of this regimen are recommended. [ABSTRACT FROM AUTHOR]

Ephemeral channels incise into the piedmonts (both alluvial fans and pediments) of the northeastern Sonoran Desert, USA. Located around metropolitan Phoenix, this tectonically quiescent region experienced only aggradation in endorheic structural basins throughout the Pliocene. A wave of aggradation then followed Salt and Gila river integration at the start of the Pleistocene. Aggradation of piedmont base levels continued throughout the rest of the Quaternary. This paper explores two hypotheses to explain piedmont incision despite rising base levels. The classic explanation is that incision is part of the evolution of desert mountain ranges as they decrease in size. A new alternative we propose here involves a lateral shift in base level from Pliocene endorheic basin playas to positions kilometers closer to range fronts in response to river integration. We present a thought exercise of modeling a pediment longitudinal profile as a 1D diffusive system, and we also analyze incision into alluvial fans of the Sierra Estrella range. While our 1D modeling results for pediments are consistent with both explanations for range-front incision, Sierra Estrella bajada incision is best explained by the sudden relocation of the base level to the toe of desert piedmonts. [ABSTRACT FROM AUTHOR]

The physicochemical properties of the nanoparticle surface determine the performance of nanocomposites in biomedical applications such as their biodistribution and pharmacokinetics. The physicochemical properties of chitosan, such as apparent charge density and solubility, are pH dependent. Similarly, Fe3O4 nanoparticles are susceptible to variations in their physicochemical properties due to changes in pH. In this work, we evaluated the physicochemical properties of chitosan–magnetite nanocomposites that were suspended at pH 7.0, 9.0, and 11.0 to determinate the effect on particle size, zeta potential, and mass percentage of the polymeric coating, in addition to the crystalline phase and magnetic properties of magnetite phase. X-ray diffraction results exposed that the present phase was magnetite with no other phases present and that the crystallite size was between 10.8 and 14.1 nm. Fourier transform infrared verified the chitosan functional groups in treated samples while the percentage of mass determined by TGA found to be nearly 9%. Scanning electron microscopy micrographs corroborated the spherical shape of the bare and chitosan-coated nanoparticles. Dynamic light scattering results showed that chitosan coating modifies the zeta potential, going from a potential of −11.8 mV for bare particles to −3.0 mV (pH 11). Besides, vibrating sample magnetometer measurements showed that coercivity remained very low, which is desirable in biomedical applications. [ABSTRACT FROM AUTHOR]

The Tachinidae (Diptera) of Chile are catalogued and information is given on distributions, name-bearing types, synonyms, nomenclatural issues, and pertinent literature. The history of tachinid collectors in Chile and authors who have contributed to the systematic knowledge of Chilean tachinids is extensively reviewed. The classification has been updated and 122 genera and 264 species are recognised in Chile. There is a significant amount of endemism with 28 genera and 100 species known only from Chile. There are also 113 species with distributions shared only between Chile and Argentina, particularly in the southern portions of these countries comprising Patagonia. The catalogue is based on examination of the original descriptions of all nominal species and all other references known to us containing relevant taxonomic and distributional information, for a total of approximately 450 references. Many of the name-bearing types and other Chilean specimens housed in collections were examined. Taxa are arranged hierarchically and alphabetically under the categories of subfamily, tribe, genus, subgenus (where recognised), and species. Nomenclatural information is provided for genus-group and species-group names, including lists of synonyms (mostly restricted to Neotropical taxa) and name-bearing type data. Species distributions are recorded by country within the New World and by larger geographical divisions in the Old World. Additional information is given in the form of notes and references under valid names at the level of tribe, genus, and species. Two genera are newly recorded from Chile: Chaetoepalpus Vimmer & Soukup, 1940 (Tachinini) (also newly recorded from Argentina) and Patelloa Townsend, 1916 (Goniini). Four species are newly recorded from Chile or other countries: Lypha ornata Aldrich, 1934 (Chile); Chaetoepalpus coquilleti Vimmer & Soukup, 1940 (Argentina and Chile); Phytomyptera evanescens (Cortés, 1967) (Argentina); and Xanthobasis unicolor Aldrich, 1934 (Chile). Eight species previously recorded from Chile are deemed to have been misidentified or misrecorded from Chile (known distributions in parentheses): Archytas incertus (Macquart, 1851) (Argentina, Brazil, Paraguay, Uruguay); Archytas seminiger (Wiedemann, 1830) (Brazil, Colombia); Gonia crassicornis (Fabricius, 1794) (Brazil, Peru, Venezuela, Middle America, West Indies, Nearctic); Lespesia andina (Bigot, 1888) (Cuba); Lespesia archippivora (Riley, 1871) (widespread Nearctic and most of Neotropical); Neoethilla ignobilis (van der Wulp, 1890) (Mexico, United States); Siphona (Siphona) geniculata (De Geer, 1776) (Palaearctic, Nearctic [introduced]); and Winthemia quadripustulata (Fabricius, 1794) (Palaearctic, Nearctic, Oriental]. As First Reviser we fix Paratheresia rufiventris Townsend, 1929 as the senior homonym and Sarcoprosena rufiventris Townsend, 1929 as the junior homonym when the two are placed together in Billaea Robineau-Desvoidy, 1830; and we fix Mayophorinia angusta Townsend, 1927 as the senior homonym and Metarrhinomyia angusta Townsend, 1927 as the junior homonym when the two are placed together in Myiopharus Brauer & Bergenstamm, 1889. New replacement names are proposed for eight preoccupied names of Neotropical species (country of type locality in parentheses): Billaea rufescens O'Hara & Wood for Sarcoprosena rufiventris Townsend, 1929, preoccupied in the genus Billaea Robineau-Desvoidy, 1830 by Paratheresia rufiventris Townsend, 1929 (Peru), nom. nov.; Billaea triquetrus O'Hara & Wood for Sarcoprosena triangulifera Townsend, 1927, preoccupied in the genus Billaea Robineau-Desvoidy, 1830 by Dexia triangulifera Zetterstedt, 1844 (Peru), nom. nov.; Eucelatoria nudioculata O'Hara & Wood for Eucelatorioidea nigripalpis Thompson, 1968, preoccupied in the genus Eucelatoria Townsend, 1909 by Chetolyga nigripalpis Bigot, 1889 (Trinidad), nom. nov.; Eucelatoria oblonga O'Hara & Wood for Urodexodes elongatum Cortés & Campos, 1974, preoccupied in the genus Eucelatoria Townsend, 1909 by Exorista elongata van der Wulp, 1890 (Chile), nom. nov.; Lespesia thompsoni O'Hara & Wood for Sturmiopsoidea obscura Thompson, 1966, preoccupied in the genus Lespesia Robineau-Desvoidy, 1863 by Eurigaster obscurus Bigot, 1857 (Cuba), nom. nov.; Myiopharus charapensis O'Hara & Wood for Metarrhinomyia angusta Townsend, 1927, preoccupied in the genus Myiopharus Brauer & Bergenstamm, 1889 by Mayophorinia angusta Townsend, 1927 (Peru), nom. nov.; Myiopharus incognitus O'Hara & Wood for Stenochaeta claripalpis Thompson, 1968, preoccupied in the genus Myiopharus Brauer & Bergenstamm, 1889 by Neoxynopsoidea claripalpis Thompson, 1968 (Trinidad), nom. nov.; and Myiopharus rufopalpus O'Hara & Wood for Paralispe palpalis Townsend, 1929, preoccupied in the genus Myiopharus Brauer & Bergenstamm, 1889 by Myioxynops palpalis Townsend, 1927 (Peru), nom. nov. New type species fixations are made under the provisions of Article 70.3.2 of the ICZN Code for three genus-group names: Parafabricia Brauer & Bergenstamm, 1894 (synonym of Archytas Jaennicke, 1867), type species newly fixed as Parafabricia perplexa Townsend, 1931; Tachinodes Brauer & Bergenstamm, 1889 (synonym of Archytas Jaennicke, 1867), type species newly fixed as Jurinia metallica Robineau-Desvoidy, 1830; and Willistonia Brauer & Bergenstamm, 1889 (synonym of Belvosia Robineau-Desvoidy, 1830), type species newly fixed as Willistonia aldrichi Townsend, 1931. Lectotypes are designated for the following four nominal species, all described or possibly described from Chile: Echinomyia pygmaea Macquart, 1851 (a valid name in the genus Peleteria Robineau-Desvoidy, 1830); Gonia chilensis Macquart, 1844 (a junior synonym of Gonia pallens Wiedemann, 1830); Masicera auriceps Macquart, 1844 (a valid name in the genus Lespesia Robineau-Desvoidy, 1863); and Prosopochoeta nitidiventris Macquart, 1851 (a valid name in the genus Prosopochaeta Macquart, 1851). The following 27 new or revived combinations are proposed (distributions in parentheses): Blepharipeza andina Bigot, 1888 is moved to Lespesia Robineau-Desvoidy, 1863 as L. andina, nomen dubium (Cuba), comb. nov.; Camposodes evanescens Cortés, 1967 is moved to Phytomyptera Rondani, 1845 as P. evanescens (Argentina, Chile), comb. nov.; Ectophasiopsis ypiranga Dios & Nihei, 2017 is moved to Trichopoda Berthold, 1827 and assigned to subgenus Galactomyia Townsend, 1908 as T. (G.) ypiranga (Argentina, Brazil), comb. nov.; Embiomyia australis Aldrich, 1934 is moved to Steleoneura Stein, 1924 as S. australis (Argentina, Chile), comb. nov.; Eurigaster modestus Bigot, 1857 is moved to Lespesia as L. modesta (Cuba), comb. nov.; Eurigaster obscurus Bigot, 1857 is moved to Lespesia as L. obscura (Cuba), comb. nov.; Macropatelloa tanumeana Townsend, 1931 is moved to Patelloa Townsend, 1916 as P. tanumeana (Argentina, Chile), comb. nov.; Masicera insignis van der Wulp, 1882 is moved to Drino Robineau-Desvoidy, 1863 as D. insignis (Argentina, Chile), comb. nov.; Parasetigena hichinsi Cortés, 1967 is moved to Chetogena Rondani, 1856 as C. hichinsi (Chile), comb. nov.; Parasetigena porteri Brèthes, 1920 and junior synonym Stomatotachina splendida Townsend, 1931 are moved to Chetogena as C. porteri (Chile), both comb. nov.; Phorocera calyptrata Aldrich, 1934 is moved to Admontia Brauer & Bergenstamm, 1889 as A. calyptrata (Argentina, Chile), comb. nov.; Poliops auratus Campos, 1953 is moved to Admontia Brauer & Bergenstamm, 1889 as A. aurata (Chile), comb. nov.; Poliops striatus Aldrich, 1934 is moved to Admontia as A. striata (Argentina, Chile), comb. nov.; Ruiziella frontosa Cortés, 1951 is moved to Chaetoepalpus Vimmer & Soukup, 1940 and placed in synonymy with C. coquilleti Vimmer & Soukup, 1940 (Argentina, Chile, Peru), comb. nov.; Ruiziella luctuosa Cortés, 1951 is moved to Chaetoepalpus as C. luctuosus (Argentina, Chile), comb. nov.; Sarcoprosena luteola Cortés & Campos, 1974 is moved to Billaea Robineau-Desvoidy, 1830 as B. luteola (Chile), comb. nov.; Sarcoprosena rufiventris Townsend, 1929 is moved to Billaea where it is a junior secondary homonym and is renamed B. rufescens O'Hara & Wood (Peru), comb. nov.; Sarcoprosena triangulifera Townsend, 1927 is moved to Billaea where it is a junior secondary homonym and is renamed B. triquetrus O'Hara & Wood (Peru), comb. nov.; Saundersia aurea Giglio-Tos, 1893 is moved to "Unplaced species of Tachinini" (Mexico), comb. nov.; Schistostephana aurifrons Townsend, 1919 is moved to Billaea as B. aurifrons (Peru), comb. nov.; Siphoactia charapensis Townsend, 1927 is moved to Clausicella Rondani, 1856 as C. charapensis (Peru), comb. nov.; Siphoactia peregrina Cortés & Campos, 1971 is moved to Clausicella as C. peregrina (Chile), comb. nov.; Sturmia festiva Cortés, 1944 is moved to Drino as D. festiva (Argentina, Chile), comb. nov.; Sturmiopsoidea obscura Thompson, 1966 is moved to Lespesia Robineau-Desvoidy, 1863, where it is a junior secondary homonym and is renamed L. thompsoni O'Hara & Wood (Trinidad), comb. nov.; Trichopoda arcuata Bigot, 1876 is returned to Trichopoda from Ectophasiopsis Townsend, 1915 and assigned to subgenus Galactomyia (Argentina, Chile), comb. revived; and Trichopoda gradata Wiedemann, 1830 is returned to Trichopoda from Ectophasiopsis and assigned to subgenus Galactomyia (Argentina, Brazil, Uruguay), comb. revived. New or revived generic and specific synonymies are proposed for the following 14 names: Camposodes Cortés, 1967 with Phytomyptera Rondani, 1845, syn. nov.; Ectophasiopsis Townsend, 1915 with Trichopoda Berthold, 1827, subgenus Galactomyia Townsend, 1908, syn. nov.; Embiomyia Aldrich, 1934 with Steleoneura Stein, 1924, syn. nov.; Fabricia andicola Bigot, 1888 with Peleteria robusta (Wiedemann, 1830), syn. revived; Macropatelloa Townsend, 1931 with Patelloa Townsend, 1916, syn. nov.; Peleteria inca Curran, 1925 with Peleteria robusta (Wiedemann, 1830), syn. revived; Poliops Aldrich, 1934 with Admontia Brauer & Bergenstamm, 1889, syn. nov.; Ruiziella Cortés, 1951 with Chaetoepalpus Vimmer & Soukup, 1940, syn. nov.; Ruiziella frontosa Cortés, 1951 with Chaetoepalpus coquilleti Vimmer & Soukup, 1940, syn. nov.; Sarcoprosena Townsend, 1927 with Billaea Robineau-Desvoidy, 1830, syn. nov.; Schistostephana Townsend, 1919 with Billaea, syn. nov.; Siphoactia Townsend, 1927 with Clausicella Rondani, 1856, syn. nov.; Stomatotachina Townsend, 1931 with Chetogena Rondani, 1856, syn. nov.; and Sturmiopsoidea Thompson, 1966 with Lespesia Robineau-Desvoidy, 1863, syn. nov. [ABSTRACT FROM AUTHOR]

Copyright of Revista Mexicana de Biodiversidad is the property of Universidad Nacional Autonoma de Mexico, Instituto de Biologia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

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Copyright of Revista de Humanidades (1130-5029) is the property of Universidad Nacional de Educacion a Distancia, Centro Asociado de Sevilla and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

A catalogue of the Pyrgotidae (Diptera) from Chile is provided. All valid names are presented, comprising three species in two genera for the country. All references known to us from the taxonomic and biological literature, to the included names, are provided, including information about name, author, year of publication, page number, type species, type locality, distribution, and references. [ABSTRACT FROM AUTHOR]

Considerable effort has been focused on improving the control of size, shape, and surface modifications to detect proteins. The purpose of this study was to compare the efficiencies of aminosilane-coated magnetite (As-M) nanoparticles (NPs), dextran-coated magnetite nanoparticles (Dx-M), and bare nanoparticles for conjugating single-chain variable fragment antibodies (scFvs) with the aim of detecting the human epidermal growth factor receptor 2 (HER2) protein. Dx-M and As-M NPs were characterized using scanning electron microscopy, energy dispersive X-ray spectroscopy, X-ray diffraction, and Raman spectroscopy. Dx-M and As-M were conjugated with a monoclonal scFv for active targeting of the HER2 antigen. Aminosilane surface coating enhanced the scFv conjugation efficiency over twofold compared to that of the dextran-coated magnetite NPs for the detection of HER2 proteins. [ABSTRACT FROM AUTHOR]

Copyright of Cirugía y Cirujanos is the property of Publicidad Permanyer SLU and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Topical antiseptics are widely used for wound treatment, with the goal of disrupting biofilm capacity. We analysed the effectiveness of a variety of antiseptics to inhibit various stages of biofilm formation and to remove biofilms in vitro as well as the agents' cytotoxic effects on fibroblasts. We found that the chlorine-releasing agents exhibited immediate anti-biofilm effects in the short term, with lesser cytotoxicity than agents prepared from more stable compounds, such as biguanide or modified diallyl disulfide-oxide, which, conversely, have better long-term effectiveness. Among the examined organisms, Gram-positive bacteria and Candida albicans were the most sensitive to the antiseptics, whereas Pseudomonas aeruginosa and Acinetobacter baumannii were relatively resistant to them. Formulations whose mechanisms of action involve the release of chemically active chlorine were more effective when administered in solution than the gel form, likely because of the stability of the active ingredients during or after preparation of the formula. Interestingly, hypochlorous acid and some superoxidation solutions were effective in preventing biofilm formation within a short time period and showed virtually no toxicity. Our study indicates that most antiseptics remain effective long enough to prevent biofilm formation; thus, even brief application of an antiseptic agent during initial wound treatment can lead to better wound management outcomes. [ABSTRACT FROM AUTHOR]

Copyright of Rastros Rostros is the property of Universidad Cooperativa de Colombia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

At the smallest scales of sediment transport in rivers, the coherent structures of the turbulent boundary layer constitute the fundamental mechanisms of bedload transport, locally increasing the instantaneous hydrodynamic forces acting on sediment particles, and mobilizing them downstream. Near the critical threshold for initiating sediment motion, the interactions of the particles with these unsteady coherent structures and with other sediment grains, produce localized transport events with brief episodes of collective motion occurring due to the near-bed velocity fluctuations. Simulations of these flows pose a significant challenge for numerical models aimed at capturing the physical processes and complex non-linear interactions that generate highly intermittent and self-similar bedload transport fluxes. In this investigation we carry out direct numerical simulations of the flow in a rectangular flat-bed channel, at a Reynolds number equal to Re = 3632, coupled with the discrete element method to simulate the dynamics of spherical particles near the bed. We perform two-way coupled Lagrangian simulations of 48,510 sediment particles, with 4851 fixed particles to account for bed roughness. Our simulations consider a total of eight different values of the non-dimensional Shields parameter to study the evolution of transport statistics. From the trajectory and velocity of each sediment particle, we compute the changes in the probability distribution functions of velocities, bed activity, and jump lengths as the Shields number increases. For the lower shear stresses, the intermittency of the global bedload transport flux is described by computing the singularity or multifr actal spectrum of transport, which also characterizes the widespread range of transport event magnitudes. These findings can help to identify the mechanisms of sediment transport at the particle scale. The statistical analysis can also be used as an ingredient to develop larger, upscaled models for predicting mean transport rates, considering the variability of entrainment and deposition that characterizes the transport near the threshold of motion. [ABSTRACT FROM AUTHOR]

Stream flow rates with seasonal, daily, or hourly cycles due to freezing and thawing can control downstream chemical processes by changing the mixing ratio of reactive flows. The extent of these hydrologic-chemical interactions has not been fully realized yet. This work explored the link between daily freeze-thaw cycles and the fate and transport of metals at a model stream impacted by acid drainage. We characterized hydrological and physicochemical parameters at the confluence between the Caracarani River (pH ~8.6) and the Azufre River (pH < 2), in northern Chile. Hourly water depth, temperature, and electrical conductivity monitoring coupled with pH and turbidity measurements revealed that maximum flow rates from thawing of the Azufre River induced characteristic daily drops in pH and turbidity. Shifts in pH controlled the precipitation and dissolution of arsenic-rich iron and aluminum reactive phases. Thus freeze-thaw processes are critical at streams receiving acid drainage where iron and aluminum phases form and are likely to impact the fate and transport of toxic metals in the system. This work highlights the importance of assessing the hydrological controls on flows and mixing ratios when studying the chemical reactivity and fate of contaminants at systems affected by acid drainage. [ABSTRACT FROM AUTHOR]

The objective of this study was to investigate if there is specific host-parasite association in Chilean populations of Trypanosoma cruzi. For this purpose, two groups of parasites were analyzed, one from chronic chagasic patients, and the other from Triatoma infestans triatomines in three regions of the country. The first group consisted of four types of samples: parasites from peripheral blood of non-cardiopathic T. cruzi infected patients (NB); parasites from their corresponding xenodiagnosis (NX); parasites from peripheral blood of T. cruzi infected cardiopathic patients (CB) and parasites from their xenodiagnostics (CX). The T. infestans sample in turn was from three regions: III, V and M (Metropolitan). The genetic differentiation by the Fisher exact method, the lineage distribution of the samples, the molecular phylogeny and the frequency of multiclonality were analysed. The results show that not only are the groups of T. cruzi clones from Chagas disease patients and vectors genetically differentiated, but also all the sub-groups (NB, NX, CB and CX) from the III, V and M regions. The analysis of lineage distribution was concordant with the above results, because significant differences among the percentages of TcI, TcIII and hybrids (TcV or TcVI) were observed. The phylogenetic reconstruction with these Chilean T. cruzi samples was coherent with the above results because the four chagasic samples clustered together in a node with high bootstrap support, whereas the three triatomine samples (III, V and M) were located apart from that node. The topology of the tree including published T. cruzi clones and isolates was concordant with the known topology, which confirmed that the results presented here are correct and are not biased by experimental error. Taken together the results presented here are concordant with a specific host-parasite association between some Chilean T. cruzi populations. [ABSTRACT FROM AUTHOR]

Recent investigations on the dynamics of the turbulent horseshoe vortex system (THV) around cylindrical piers have shown that the rich coherent dynamics of the vortical structures is dominated by low-frequency bimodal fluctuations of the velocity field. In spite of these advances, many questions remain regarding the changes of the flow and sediment transport dynamics as scour progresses. In this investigation we carry out laboratory experiments to register the development of the scour hole around a cylindrical pier in a fine-sand bed ( d = 0.36 mm). We use the bathymetry measured in the experiment to simulate the flow field employing the detached-eddy simulation approach (DES), which has shown to resolve most of the turbulent stresses around surface-mounted obstacles. From these simulations we compare the dynamics of the THV to the flat-bed case, and analyze the effects on particle transport and sediment flux using the Lagrangian particle model of Escauriaza and Sotiropoulos (2011b) to study the impact of the changes of the flow on the sediment dynamics. [ABSTRACT FROM AUTHOR]

To investigate whether Trypanosoma cruzi populations found in chagasic cardiopathic and non-cardiopathic patients are genetically differentiated, three molecular microsatellite markers were analysed. This analysis was also applied to compare T. cruzi samples from peripheral blood or dejections of Triatoma infestans fed on the blood of the same patients. In order to obtain the first objective, analyses of predominant T. cruzi genotypes were conducted using three approaches: a locus-by-locus analysis; a Fisher method across three loci; and analysis of molecular variance by Genepop and Arlequin programs. Only with one locus and on the blood samples was a significant differentiation detected among non-cardiopathic and cardiopathic groups, which was not confirmed by the other two methods. On the contrary, with the three approaches, it was found that T. cruzi clones present in the blood of patients are genetically differentiated from those detected in dejections of T. infestans fed on the same patients. Our results showed that the most frequent lineage both in blood as well as in triatomine dejection samples was TcI. No significant difference in T. cruzi lineage distribution was observed among chagasic cardiopathic and non-cardiopathic patients. The majority of the samples (50–60%) had only one T. cruzi clone (uniclonal) either in blood or dejection samples. [ABSTRACT FROM AUTHOR]