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Abstract Background Exposure to pesticides in the living environment can be associated with the prevalence of health symptoms. This study investigates associations between health symptoms among residents in areas with fruit crop fields where pesticides are applied, and psychological perceptions and attitudes about environmental aspects and exposures. Methods A cross-sectional survey combined with routine primary care electronic health records (EHR) data was conducted in 2017 in rural areas of the Netherlands with high concentration of fruit crops (n = 3,321, aged ≥ 16 years). Individual exposure to pesticides was estimated using geocoded data on fruit crops around the home. Validated instruments were used to assess symptom report and psychological perceptions and attitudes. Annual prevalence of various health symptoms was derived from EHRs. Multilevel regression models were used to analyze associations between health symptoms (outcome), fruit crops, and multiple psychological perceptions and attitudes (confounders). Results Living in the vicinity of fruit crop fields was generally not associated with self-reported symptom duration and general practitioner (GP) registered symptoms. For self-reported symptoms, symptom prevalence decreased when crop density within 250 m and 500 m from the home increased. No associations were found at other distances. Furthermore, higher levels of environmental worries, perceived exposure, and perceived sensitivity to pesticides and attribution of symptoms to environmental exposures were generally associated with a higher number of self-reported symptoms, and longer symptom duration. Symptoms reported to GPs were not associated with psychological perceptions and attitudes, except for perceived sensitivity to pesticides. Conclusion Psychological perceptions and attitudes appear to be related to self-reported symptoms, but not to GP-registered symptoms, independent of the actual levels of exposure as measured by the size of the area of crop fields. Perceptions about environmental factors should be taken into account in environmental health risk assessment research when studying health symptoms.

Recent studies have shown that variations in the parameters of the laser powder bed fusion (LPBF) process significantly impact the microstructure and thermomechanical properties of NiTi shape memory alloys (SMAs). Understanding how parameter selection influences the final NiTi SMA properties enables the strategic design of additively manufactured (AM) components with tailored mechanical and transformation behavior, suitable for specific applications in a plethora of scientific fields. However, the connection between processing and thermomechanical properties of NiTi SMAs is still not completely understood. This study investigates the effects of AM parameters laser power (72–185 W), scanning speed (668-1739 mm/s), and hatch spacing (28–85 μm) on a near equiatomic NiTi powder. Low porosity levels are found in the samples additively manufactured (AM) with the different LPBF parameter combinations. The findings also reveal that transformation temperatures and nickel evaporation trends correlate directly with volumetric energy density (VED). Additionally, the amount of Ti2Ni precipitates increases with higher VED. Thermal cycles under constant stress, training, and two-way shape memory effect tests have been performed; the results demonstrate a strain recovery ratio of 2–3.5% for most of the samples. The results arising from this study pave the way for the engineering of customized materials with tailored properties from the same alloy metal powder.

The pandemic brought about an unprecedented number of virtual conferences, given the heavy restrictions on travel to in-person meetings. Despite all the advances in technology, people still complain about virtual events. There is Zoom fatigue, confinement malaise, and a longing for personal social interactions. This paper discusses our experience organizing the IEEE Virtual Reality Conference (IEEE VR) as a virtual event. IEEE VR was a success with 1200+ registered paying participants, dozens of workshops and tutorials, and hundreds of technical papers. We used (1) a virtual environment platform, together with (2) discussion tools and (3) videoconferencing/broadcast/online tools to further provide effective social interaction and increase engagement. In this paper, we explore the synergies between virtual environments and other online tools and assess user engagement by analyzing the messages exchanged between participants across different genders and geographical regions. To this end, we apply diverse engagement metrics for online conferences. Our analysis shows that these metrics have the potential to highlight engagement, diversity, and inclusion by combining textual messages, participant geographic and gender information, communities of participants, and visitation patterns in a virtual environment. Drawing on our results and experiences, we propose guidelines for organizing technical virtual events to increase diversity and social interaction.

The Andes are an emblematic active Cordilleran orogen. Mountain building in the Central Andes (∼20∘ S) started by the Late Cretaceous to early Cenozoic along the subduction margin and propagated eastward. In general, the structures sustaining the uplift of the western flank of the Andes are dismissed, and their contribution to mountain building remains poorly constrained. Here, we focus on two sites along the Western Andes at ∼20–22∘ S in the Atacama desert, where structures are well exposed. We combine mapping from high-resolution satellite images with field observations and numerical trishear forward modeling to provide quantitative constraints on the kinematic evolution of the investigated field sites. When upscaling our local field interpretations to the regional scale, we identify two main structures: (1) the Andean Basement Thrust, a west-vergent thrust system placing Andean Paleozoic basement over Mesozoic strata, and (2) a series of west-vergent thrusts pertaining to the West Andean Thrust System, deforming primarily Mesozoic units. From our interpreted sections, we estimate that both structures together accommodate at least ∼6–9 km of shortening across the sole investigated ∼7–17 km wide field sites. This multi-kilometric shortening represents only a fraction of the total shortening accommodated across the whole Western Andes. The timing of the main deformation recorded in the folded Mesozoic series can be bracketed between ∼68 and ∼29 Ma – and possibly between ∼68 and ∼44 Ma – from dated deformed geological layers, with a subsequent significant slowing-down of shortening rates. Even though the structures forming the Western Andes only absorbed a small fraction of the total shortening across the whole orogen, their contribution was relatively significant at the earliest stages of Andean mountain building before deformation proceeded eastward.

This study examined whether the intensity of endurance stimuli modifies the adaptation in strength and endurance following concurrent training and whether the acute molecular response to concurrent exercise is affected by training status. Using a parallel group design, trained cyclists were randomized to either resistance exercise followed by moderate intensity continuous training (RES + MICT, n = 6), or resistance exercise followed by work matched high intensity interval training (RES + HIIT, n = 7), across an 8 weeks training programme. A single RES + MICT or RES + HIIT exercise stimulus was completed 1 week before and within 5 days of completing the training programme, to assess phosphorylation of protein kinases of the mTOR and AMPK signaling pathways. There were no main effects of time or group on the phosphorylation of protein kinases in response to concurrent exercise stimulus pre- and post-training intervention (p > 0.05). Main effects of time were observed for all maximal strength exercises; back-squat, split-squat, and calf-raise (p < 0.001), with all improving post intervention. A time × group interaction was present for V̇O2peak, with the RES + MICT group displaying a preferential response to that of the RES + HIIT group (p = 0.010). No time nor group effects were observed for 5 min time trial performance, power at 2 and 4 mmol L−1 (p > 0.05). Whilst preliminary data due to limited sample size the intensity of endurance activity had no effect on performance outcomes, following concurrent training. Further, the acute molecular response to a concurrent exercise stimulus was comparable before and after the training intervention, suggesting that training status had no effect on the molecular responses assessed.

Basin-averaged denudation rates may locally exhibit a wide dispersion, even in areas where the topographic steady state is supposedly achieved regionally. This dispersion is often attributed to the accuracy of the data or to some degree of natural variability of local erosion rates which can be related to stochastic processes such as landsliding. Another physical explanation of this dispersion is local and transient disequilibrium between tectonic forcing and erosion at the scale of catchments. Recent studies have shown that basin divide migration can potentially induce such perturbations, and they propose metrics to assess divide mobility based on cross-divide contrasts in headwater topographic features. Here, we use a set of landscape evolution models assuming spatially uniform uplift, rock strength and rainfall to assess the effect of divide mobility on basin-wide denudation rates. We propose using basin-averaged aggressivity metrics based on cross-divide contrasts (1) in channel χ, an integral function of position in the channel network; (2) in channel local gradient; and (3) in channel height, measured at a reference drainage area. From our simulations, we show that the metric based on differences in χ is the most reliable to diagnose local disequilibrium. The other metrics are more suitable for relatively active tectonic regions such as mountain belts, where contrasts in local gradient and elevation are more important. We find that the ratio of basin denudation associated with drainage migration to uplift can reach a factor of 2, regardless of the imposed uplift rate, erodibility, diffusivity coefficient or critical hillslope gradient. A comparison with field observations in the Great Smoky Mountains (southern Appalachians, USA) underlines the difficulty of using the metric based on χ, which depends on the – poorly constrained – elevation of the outlet of the investigated catchment. Regardless of the considered metrics, we show that observed dispersion is controlled by catchment size: a smaller basin may be more sensitive to divide migration and hence to disequilibrium. Our results thus highlight the relevance of divide stability analysis from digital elevation models as a fundamental preliminary step for basin-wide denudation rate studies based on cosmogenic radionuclide concentrations.

Nonalcoholic fatty liver disease (NAFLD) is characterized by the development of steatosis, which can ultimately compromise liver function. Mitochondria are key players in obesity-induced metabolic disorders; however, the distinct role of hypercaloric diet constituents in hepatic cellular oxidative stress and metabolism is unknown. Male mice were fed either a high-fat (HF) diet, a high-sucrose (HS) diet or a combined HF plus HS (HFHS) diet for 16 weeks. This study shows that hypercaloric diets caused steatosis; however, the HFHS diet induced severe fibrotic phenotype. At the mitochondrial level, lipidomic analysis showed an increased cardiolipin content for all tested diets. Despite this, no alterations were found in the coupling efficiency of oxidative phosphorylation and neither in mitochondrial fatty acid oxidation (FAO). Consistent with unchanged mitochondrial function, no alterations in mitochondrial-induced reactive oxygen species (ROS) and antioxidant capacity were found. In contrast, the HF and HS diets caused lipid peroxidation and provoked altered antioxidant enzyme levels/activities in liver tissue. Our work provides evidence that hepatic oxidative damage may be caused by augmented levels of peroxisomes and consequently higher peroxisomal FAO-induced ROS in the early NAFLD stage. Hepatic damage is also associated with autophagic flux impairment, which was demonstrated to be diet-type dependent. The HS diet induced a reduction in autophagosomal formation, while the HF diet reduced levels of cathepsins. The accumulation of damaged organelles could instigate hepatocyte injuries and NAFLD progression.

Myelin, the insulating sheath around axons, supports axon function. An important question is the impact of mild myelin disruption. In the absence of the myelin protein proteolipid protein (PLP1), myelin is generated but with age, axonal function/maintenance is disrupted. Axon disruption occurs in Plp1-null mice as early as 2 months in cortical projection neurons. High-volume cellular quantification techniques revealed a region-specific increase in oligodendrocyte density in the olfactory bulb and rostral corpus callosum that increased during adulthood. A distinct proliferative response of progenitor cells was observed in the subventricular zone (SVZ), while the number and proliferation of parenchymal oligodendrocyte progenitor cells was unchanged. This SVZ proliferative response occurred prior to evidence of axonal disruption. Thus, a novel SVZ response contributes to the region-specific increase in oligodendrocytes in Plp1-null mice. Young adult Plp1-null mice exhibited subtle but substantial behavioral alterations, indicative of an early impact of mild myelin disruption.

Introducción: El propósito de la investigación es conocer la eficacia del Secnidazol en el tratamiento de escolares asintornáticos portadores de Giardia lamblia y lo Entamoeba histolytica, así como el evaluar su tolerancia. Material y métodos: Se escogieron 50 niños parasitados (totalizando 53 casos con Entamoeba histolytica y/o Giardia lamblia), con edades comprendidas entre 5 y 14 años, de uno u otro sexo, a quienes se les administró el medicamento y tres días después se realizaron exámenes coproparasitológicos controles. La tolerancia del medicamento se evaluó mediante encuesta. Resultados: De 53 casos parasitados, la relación de protozoarios fue: Giardia lamblia (66,03%) seguidos de Entamoeba histolytica (33,97%). La efectividad parasitológica del Secnidazol contra Giardia lamblia fue del 100% y de Entamoeba histolytica de 95,45%. Se obtuvo un solo caso portador que no respondió al tratamiento (4.55%). El medicamento fue bien tolerado en el 50% de los casos. Los síntomas más frecuentes fueron: hiporexía, cefalea, dolor abdominal, mareos, náuseas, vómitos, diarrea, fatiga, alteración del gusto y prurito. Conclusiones: La eficacia y la relativamente buena tolerancia del Secnidazol fue demostrada en el presente estudio. Se obtuvo cura parasitológica al tercer día de administrado el medicamento.

Introducción: El propósito de la investigación es conocer la prevalencia de las enteroparasitosis en una escuela urbana de la parroquia San Francisco. Material y métodos: Del total de la población escolar, se escogieron 114 niños, de edades comprendidas entre 5 y 15 años, de ambos sexos, donde se les realizó exámenes coproparasitológicos y recolección de información a través de encuestas epidemiológicas. Resultados: De los niños seleccionados. 74,56% reportaron positividad para uno o más enteroparásitos. 40,35% fueron masculinos y 34,21 % femeninos. Las edades más parasitadas fueron las comprendidas entre 9 y 12 años (34,24%) seguidas de 5 a 8 años 30,69%. Los helmintos más frecuentes fueron: Enterobius vermicularis (45,55%), Trichuris trichiura (27,80%), Ascaris lumbricoides (23,35%) e Hymenolepis nana (3,30%) y los protozoos fueron: Blastocystis hominis (37,28%), Giardia lamblia (17,79%), Endolimax nana (16,95%), Entamoeba coli (15.26%). El poliparasitismo predominó sobre el monoparasitismo. Las helmintiasis observadas presentaron en su mayoría una infestación leve. Se evidencia acentuados malos hábitos higiénicos en los niños así como en la escuela.

In this paper we assess the role of the protein MKS1 (Meckel syndrome type 1) in the cortical membrane mechanics of the ciliated protist Paramecium. This protein is known to be crucial in the process of cilium formation, and we investigate its putative role in membrane–cytoskeleton attachment. Therefore, we compare cells where the gene coding for MKS1 is silenced to wild-type cells. We found that scanning electron microscopy observation of the cell surface reveals a cup-like structure in wild-type cells that is lost in silenced cells. Since this structure is based on the underlying cytoskeleton, one hypothesis to explain this observation is a disruption of membrane attachment to the cytoskeleton in the absence of MKS1 that should affect plasma membrane mechanics. We test this by probing the mechanics of wild-type and silenced cells by micropipette aspiration. Strikingly, we observe that, at the same aspiration pressure, the membrane of silenced cells is easily aspirated by the micropipette whereas that of wild-type cells enters only at a moderate velocity, an effect that suggests a detachment of the membrane from the underlying cytoskeleton in silenced cells. We quantify this detachment by measuring the deformation of the cell cortex and the rate of cell membrane entry in the micropipette. This study offers a new perspective for the characterization of membrane–cytoskeleton attachment in protists and paves the way for a better understanding of the role of membrane–cortex attachment in cilium formation.