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Background: The concept of entrapment has been highlighted as a transdiagnostic element that manifests itself in disorders such as depression, anxiety, and suicidal ideation. Although research has been conducted in different contexts independently, a comprehensive multi-country study to assess gender differences in entrapment through network analysis has not yet been carried out. The objective of this study was to evaluate the entrapment network in men and women at the multinational level. Methods: A sample of 2,949 participants, ranging in age from 18 to 73 years from six countries (Germany, Iran, Spain, Slovakia, El Salvador, and Peru), was considered. They completed the entrapment scale. A network analysis was performed for both men and women to identify the connectivity between indicators and the formation of clusters and domains, in addition to the centrality assessment in both sex groups. Results: The study findings revealed the presence of a third domain focused on external interpersonal entrapment in the network of men and women. However, in relation to the interconnectivity between domains, variations were evidenced in both networks, as well as in centrality, it was reported that men present a greater generalized entrapment in various aspects of life, while women tend to experience a more focused entrapment in expressions of intense emotional charge. Conclusion: The multinational study identified variations in the structure of entrapment between genders, with three domains (internal, external, and external-interpersonal) and differences in the interaction of indicators and groupings, as well as discrepancies in centrality.

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BACKGROUND: Experiential avoidance (EA) is a psychological mechanism associated with several mental health disorders and is regarded as a relevant target by third-generation cognitive behavioral therapies. It has been mainly assessed through self-report questionnaires, and the AAQ-II is the most used tool. Its psychometric evidence has been mostly tested through the classical test theory (CTT) and very scarcely assessed through Item Response Theory (IRT). METHODS: We used the Graded Response Model to examine its psychometric properties in Spanish-speaking university students (n = 1503; women = 995 (66.2%), mean age = 19.29, SD = 2.45). We tested whether the empirical data fit the model's predictions and estimated the dispersion of persons and items along the experiential avoidance continuum. Moreover, we examined category probability curves to identify the response probability of each answer. Likewise, an item-person map was made where the measurement of persons and items, both on the same scale and along the experiential avoidance continuum, could be observed jointly. Finally, we tested the gender invariance of the scale. RESULTS: We found that the values of the individuals and the items were in the established range to be considered an adequate measure of EA. Additionally, we observed high discrimination indices for all items. The current version with seven answer options could not be optimal and should be tested in future studies. Finally, we found evidence of differential functioning by gender in one of the seven items of the instrument. CONCLUSIONS: Our results indicate that the AAQ-II is a suitable tool for measuring EA and accurately classifying and differentiating EA levels in university students.

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A string of fierce fires broke out in Chile in the austral summer 2023, just six years after the record-breaking 2017 fire season. Favored by extreme weather conditions, fire activity has dramatically risen in recent years in this Andean country. A total of 1.7 million ha. burned during the last decade, tripling figures of the prior decade. Six of the seven most destructive fire seasons on record occurred since 2014. Here, we analyze the progression during the last two decades of the weather conditions associated with increased fire risk in Central Chile (30°-39° S). Fire weather conditions (including high temperatures, low humidity, dryness, and strong winds) increase the potential for wildfires, once ignited, to rapidly spread. We show that the concurrence of El Niño and climate-fueled droughts and heatwaves boost the local fire risk and have decisively contributed to the intense fire activity recently seen in Central Chile. Our results also suggest that the tropical eastern Pacific Ocean variability modulates the seasonal fire weather in the country, driving in turn the interannual fire activity. The signature of the warm anomalies in the Niño 1 + 2 region (0°-10° S, 90° W-80° W) is apparent on the burned area records seen in Central Chile in 2017 and 2023.

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AIM: To assess the effectiveness of Bacillus subtilis strain LN8B as a biocollector for recovering pyrite (Py) and chalcopyrite (CPy) in both seawater (Sw) and deionized water (Dw), and to explore the underlying adhesion mechanism in these bioflotation experiments. MATERIALS AND METHODS: The bioflotation test utilized B. subtilis strain LN8B as the biocollector through microflotation experiments. Additionally, frother methyl isobutyl carbinol (MIBC) and conventional collector potassium amyl xanthate (PAX) were introduced in some experiments. The zeta potential (ZP) and Fourier-transform infrared spectroscopy (FTIR) was employed to explore the adhesion mechanism of Py and CPy interacting with the biocollector in Sw and Dw. The adaptability of the B. subtilis strain to different water types and salinities was assessed through growth curves measuring optical density. Finally, antibiotic susceptibility tests were conducted to evaluate potential risks of the biocollector. RESULTS: Superior outcomes were observed in Sw where Py and CPy recovery was ∼39.3% ± 7.7% and 41.1% ± 5.8%, respectively, without microorganisms' presence. However, B. subtilis LN8B potentiate Py and CPy recovery, reaching 72.8% ± 4.9% and 84.6% ± 1.5%, respectively. When MIBC was added, only the Py recovery was improved (89.4% ± 3.6%), depicting an adverse effect for CPy (81.8% ± 1.1%). ZP measurements indicated increased mineral surface hydrophobicity when Py and CPy interacted with the biocollector in both Sw and Dw. FTIR revealed the presence of protein-related amide peaks, highlighting the hydrophobic nature of the bacterium. The adaptability of this strain to diverse water types and salinities was assessed, demonstrating remarkable growth versatility. Antibiotic susceptibility tests indicated that B. subtilis LN8B was susceptible to 23 of the 25 antibiotics examined, suggesting it poses minimal environmental risks. CONCLUSIONS: The study substantiates the biotechnological promise of B. subtilis strain LN8B as an efficient sulfide collector for promoting cleaner mineral production. This effectiveness is attributed to its ability to induce mineral surface hydrophobicity, a result of the distinct characteristics of proteins within its cell wall.

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Chile leads cherry exports in the southern hemisphere with a total of 415.315 t exported in the 2022 to 2023 season (IQonsulting, 2023). Cytospora canker, produced by Cytospora spp., causes destructive infections and limit the productivity of sweet cherry orchards (Luo et al. 2019). This study was focused on isolating Cytospora strains to identify and characterize the species present in sweet cherry. During the period 2019-2022, ten samples of stem or branch presenting canker, dieback, gummosis or dead buds, were collected from sweet cherry cultivars 'Skeena', 'Lapins', 'Santina', 'Sweetheart', and 'Regina', in the regions Ñuble and O'Higgins, Chile. Five mm pieces from the necrotic wood margins of the samples were rinsed with sterile deionized water, placed on potato dextrose agar (PDA, Difco) and incubated at 20±2 ºC for 5 days. One isolate was recovered from each sample, resulting in ten Cytospora-like strains. Single hyphal tips were transferred onto PDA plates and all isolates were deposited in the Chilean Collection of Microbial Genetic Resources (CChRGM). Colonies grown on PDA reached 89 mm in diameter in 10 d at 25 °C, showing irregular margin, lacking aerial mycelium, initially off-white to cream that turned greenish gray in the center, which darkens with age. After 20 days of culturing on pine needle agar (Chen et al. 2015), isolates produced conidiomata pycnidial, semi-immersed, black, and subglobose (362)445-555(681)×(357)528-700(1053) µm (n=10), generating amber slimy conidia masses; Conidiophores were phialidic, cylindrical, aseptate, hyaline (6.77)9-10.04(12.88)×(0.82)1.1-1.28(1.99) µm (n = 30); conidia were abundant, allantoid, hyaline to light brown, aseptate (3.39)4.28-4.57(5.36)×(0.69)0.96-1.09(1.47) µm (n = 30) (Supplementary Figure 1). No sexual morph was observed. With the exception of the strain RGM 3390, all the isolates shared morphological characters to the descriptions of Cytospora sorbicola Norphanph., Bulgakov, T. C. Wen & K. D. Hyde (Norphanphoun et al. 2017). Isolates were identified at species level, by sequencing DNA regions described by Pan et al. (2020): ITS1-5.8S-ITS2, LSU; act, tef-1α, and tub2 with the exception of the RBP2, because this region could not be amplified in seven out of ten isolates. The consensus tree included the concatenated sequences of the ten isolates and those of reference Cytospora species reported by Ilyukhin et al. (2023) using a maximum likelihood analysis with the tool IQ-TREE webserver. MLSA confirmed the taxonomic affiliation of nine of the isolates with C. sorbicola and one isolate with Cytospora sp. (RGM 3390), that might represent a novel species (Supplementary Figure 2). The isolates RGM 3399 and RGM 3400, were selected randomly for pathogenicity tests. Inoculations were performed on 2-year-old sweet cherry cv. 'Lapins' grow in pots in a greenhouse at 26±6°C. Seven plants per isolate were cut to about 6-cm length from the main stem, and inoculated onto fresh cuts with 5-mm mycelium PDA plugs of 5-d-old culture and wrapped in moist sterile cotton and parafilm to keep moisture. Six plants were inoculated with non-colonized PDA agar plugs as control. The average canker length 3 months after inoculation was 3.1 and 0.8 cm, for RGM 3389 and RGM 3400, respectively (Supplementary Figure 1). Symptomatic twigs were incubated in moist chambers at 20±2 ºC for 10 d, resulting in the re-isolation of Cytospora strains that produced pycnidia and conidia structures in agreement with C. sorbicola. Both strains were reidentified to fulfill Koch's postulates, control twigs remained asymptomatic and no fungus was isolated from these twigs. This is the first report of C. sorbicola causing canker on sweet cherry in Chile. Our findings suggest that this species could be the most recurrent in cherry in central Chile, coinciding with it found in California where C. sorbicola has been described as the main causal agent of Cytospora canker of stone fruits in California (Lawrence et al. 2018).

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Coffee is a crop of global relevance. Indirect somatic embryogenesis has allowed plants of different coffee genotypes to be massively regenerated. The culture medium composition can affect the calli characteristics that are generated and their ability to form somatic embryos. This research aimed to determine the influence of the type of callus, growth regulators, and phytagel concentration on the embryogenic capacity of the Colombia variety. Leaf explants were cultured on Murashige and Skoog medium with 2,4-dichlorophenoxyacetic acid (2,4-D) (0.5-1.0 mg L-1), benzylaminopurine (BAP, 1.0 mg L-1), and phytagel (2.3-5.0 g L-1). The explants generated two types of calli: friable (beige, soft, watery, easy disintegration, polyhedral parenchyma cells) and compact (white, hard, low water content, difficult disintegration, elongated parenchyma cells). About 68% of the total callus generated was compact; this type of callus produced a greater number of embryos (71.3) than the friable one (29.2). The number of differentiated embryos was significantly affected by the concentration of phytagel; higher concentrations (5.0 g L-1) resulted in larger quantities (73.7). The highest number of embryos (127.47) was obtained by combining 1.0 mg L-1 2,4-D, 1.0 mg L-1 BAP, 5.0 g L-1 phytagel, and compact callus.

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The angular distribution of the sky radiance determines the energy generation of solar power technologies as well as the ultraviolet (UV) doses delivered to the biosphere. The sky-diffuse radiance distribution depends on the wavelength, the solar elevation, and the atmospheric conditions. Here, we report on ground-based measurements of the all-sky radiance at three sites in the Southern Hemisphere across a transect of about 5,000 km: Santiago (33°S, a mid-latitude city of 6 million inhabitants with endemic poor air quality), King George Island (62°S, at the northern tip of the Antarctic Peninsula, one of the cloudiest regions on Earth), and Union Glacier (79°S, a snow-covered glacier in the vast interior of Western Antarctica). The sites were strategically selected for studying the influence of urban aerosols, frequent and thick clouds, and extremely high albedo on the sky-diffuse radiance distribution. Our results show that, due to changing site-specific atmospheric conditions, the characterization of the weather-driven sky radiance distribution may require ground-based measurements.

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Berries comprise an economically important group of crops. Knowledge about their arthropod pests and biological control agents is important in the development of more efficient integrated pest management programs. Identification of potential biocontrol agents based solely on morphological attributes may be difficult and so molecular techniques should be incorporated. Here we studied the species diversity of predatory mites in the family Phytoseiidae, and how this diversity is affected by the berry species and crop management approaches, specifically pesticide application regimes. We sampled 15 orchards in the State of Michoacán, Mexico. Sites were selected based on berry species and pesticide regimes. Mite identification was achieved by combining morphological attributes and molecular techniques. Phytoseiidae diversity was compared amongst blackberry, raspberry and blueberry. Subsequently we studied the effect of berry species and pesticide regime on the abundance of the most prevalent phytoseiid species. We identified 11 species of phytoseiid mites. The greatest species diversity was found in raspberry, followed by blackberry and then blueberry. The most abundant species were Typhlodromalus peregrinus and Neoseiulus californicus. The abundance of T. peregrinus was significantly affected by pesticide application but not by berry species. In contrast, abundance of N. californicus was significantly affected by berry species but not by pesticide regime.

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Since 2005 in Íxtaro, Michoacán, symptoms of Harzia infection have been observed on immature Annona cherimola fruit with Colletotrichum fragariae-induced anthracnose lesions and mummified fruit. This study aimed to identify the Harzia sp. and evaluate its pathogenicity. Four isolates were obtained from fruit exhibiting symptoms, cultured in four types of agar under various conditions, and characterized based on concatenated internal transcribes spacer (ITS) + large subunit and ITS + small subunit sequences. Additionally, the isolates were compared with two CBS species (two-type strains and two isolates) of Harzia patula and H. tenella under the same conditions as the Harzia isolates, and all known Harzia spp. in culture were included in two phylogenetic analyses. H. ixtarensis sp. nov. was proposed. Compared with H. patula CBS isolate 121524 which was the most closely phylogenetically related species, H. ixtarensis was characterized by slower colony growth (white to salmonish-beige), different percentages of two forms of conidia (elongated and globose; unicellular and hyaline to subhyaline), and smaller conidia. The conidia mainly germinated with two hyaline tubes without an appressorium. In situ inoculations (1 × 106 ml-1 conidia suspension) of fruit showed that fruit with wounds developed larger lesions than those without wounds. Harzia inoculation on anthracnose lesions (induced by prior inoculation with C. fragariae) produced larger anthracnose lesions than C. fragariae alone. When C. fragariae or H. ixtarensis was inoculated alone, the lesion size was 51 and 99% smaller, respectively, indicating synergy between C. fragariae and H. ixtarensis. Thus, H. ixtarensis may have a parasitic-synergistic and necrotrophic lifestyle, and exhibited symptoms on anthracnose lesions.

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BACKGROUND: The Generalized Anxiety Disorder 7-item (GAD-7) scale is widely used for the assessment of generalized anxiety disorder. AIM: To adapt the GAD-7 to the Chilean adolescent population and to evaluate its psychometric properties. MATERIAL AND METHODS: The GAD-7 was adapted and administered to 2,022 adolescents between 13 and 19 years of age, recruited from eight schools in the northern area of Santiago, Chile. Other self-report instruments were used to assess depressive symptoms and health-related quality of life. The one factor structure and invariance by sex were examined using Confirmatory Factor Analysis. Its reliability and validity based on its relationship with other variables were assessed. RESULTS: The one-factor structure and invariance by sex were confirmed. The results showed an adequate internal reliability (Cronbach's alpha = 0.86, Spearman-Brown coefficient = 0.82). As expected, significant correlations were observed with measures of depressive symptoms and health-related quality of life. Higher scores were observed in women than in men. CONCLUSIONS: The Chilean version adapted for adolescents of the GAD-7 has good psychometric properties. Thus, it may be a useful and valid instrument for the assessment of generalized anxiety disorder in adolescents in Chile.

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Vaccinium corymbosum L. is the most cultivated blueberry species in Chile. Chilean fruits typically take up to 50 days to reach oversea markets; therefore, controlling post-harvest pathogens is of outmost importance to maintain international food safety and quality standards. In February 2019, the Microbial Genetic Resources Bank at INIA received fruits of V. corymbosum cv. 'Brigitta Blue' from Mariquina (-39.567869, -72.992461), located in the southern Chilean blueberry production zone, for post-harvest disease diagnosis. Asymptomatic fruits were incubated in moist-chambers at 25 °C with light/darkness cycles of 12 h. After 5 d, some fruits showed sunken areas and small surface wounds that exudated orange masses of conidia; under the epidermis, gray acervuli were also detected. After 15d, these fruits became dehydrated, mummified, and covered by mycelia, all characteristic symptoms of anthracnose (Wharton and Schilder 2008). In Chile, Colletotrichum gloeosporioides has, thus far, been the only causal agent of anthracnose reported in blueberry (Lara et al. 2003). Conidia exudated from the diseased fruit were inoculated on potato-dextrose agar (PDA) and incubated at 25 °C for 7 d. The resulting colony was predominantly cottony with gray aerial mycelium, displaying masses of pale orange conidia; on the reverse side, the colony was a pink-reddish color. Under a microscope, conidia were hyaline, fusiform to elliptic in shape, and displaying guttulate of 12.2±1.2 × 4.17±0.3 µm (n=30), characteristics coinciding with those described for Colletotrichum fioriniae (Pennycook 2017; Shivas and Tan 2009) (Supplementary Figure 1). The isolate was deposited in the Chilean Collection of Microbial Genetic Resources (CChRGM) as RGM 3330. Genomic DNA extraction of RGM 3330 and phylogenetic analyses were carried out according to Cisterna-Oyarce et al. (2022). A multi-locus sequencing analysis was carried out using five genetic markers. The internal transcribed spacer (ITS), glyceraldehyde 3-phosphate dehydrogenase (gapdh), actin (act), and chitin synthase 1 (chs-1) were PCR-amplified following Damm et al. (2012) and -tubulin (tub) following Glass and Donaldson (1995). Sequences were deposited in GenBank (ON364141 for ITS and ON369167-70 for tub, act, chs-1, and gapdh, respectively) (Sayers et al. 2021). A BLAST analysis carried out in SequenceServer (Priyam et al. 2019), using a custom database of sequences retrieved from Damm et al. (2012) and Liu et al. (2020), showed that all genetic markers were 100% identical to those of C. fioriniae CBS 128517T (ITS (540/540 identities), gapdh (249/249), act (245/245), and chs-1 (274/274)), except for tub, which shared 99.8% of its identities (416/417) with this species. Maximum likelihood phylogenetic estimation clustered RGM 3330 with C. fioriniae strains CBS 128517T and CBS 126526 with 100% bootstrap support (Supplementary Figure 1). Koch's postulates were carried out with asymptomatic fruits of V. corymbosum cv. 'Brigitta Blue'. Prior to inoculation, fruits were surface-sterilized for 10 s in 70% ethanol, 3 s in 1% NaOCl, 10 s in 70% ethanol, rinsed three times with sterile distilled water, and subsequently placed in moist-chambers. Two groups of three repetitions of 20 fruits each were sprayed with 9 × 106 conidia/mL of RGM 3330 for the first group and with sterile distilled water for the control. After 5 d at 25 °C with light/darkness cycles of 12 h, only fruits sprayed with the conidial solution developed symptoms of anthracnose and the re-isolated fungi were identical in morphology to RGM 3330. This is the first report of C. fioriniae in blueberry in Chile. References Cisterna-Oyarce, V., Carrasco-Fernández, J., Castro, J. F., Santelices, C., Muñoz-Reyes, V., Millas, P., Buddie, A. G., and France, A. 2022. Gnomoniopsis smithogilvyi: identification, characterization and incidence of the main pathogen causing brown rot in postharvest sweet chestnut fruits (Castanea sativa) in Chile. Australasian Plant Disease Notes 17:2. Damm, U., Cannon, P. F., Woudenberg, J. H., and Crous, P. W. 2012. The Colletotrichum acutatum species complex. Stud. Mycol. 73:37-113. Glass, N. L., and Donaldson, G. C. 1995. Development of primer sets designed for use with the PCR to amplify conserved genes from filamentous ascomycetes. Appl. Environ. Microbiol. 61:1323-1330. Lara, O., Velazquez, C. G., and Ascencio, C. 2003. Colletotrichum gloeosporiodes in blueberry fruit. in: XIII Congreso de Fitopatología. Liu, X., Zheng, X., Khaskheli, M. I., Sun, X., Chang, X., and Gong, G. 2020. Identification of Colletotrichum species associated with blueberry anthracnose in Sichuan, China. Pathogens 9:718. Pennycook, S. 2017. Colletotrichum fioriniae comb. & stat. nov., resolving a nomenclatural muddle. Mycotaxon 132:149-152. Priyam, A., Woodcroft, B. J., Rai, V., Moghul, I., Munagala, A., Ter, F., Chowdhary, H., Pieniak, I., Maynard, L. J., Gibbins, M. A., Moon, H., Davis-Richardson, A., Uludag, M., Watson-Haigh, N. S., Challis, R., Nakamura, H., Favreau, E., Gómez, E. A., Pluskal, T., Leonard, G., Rumpf, W., and Wurm, Y. 2019. Sequenceserver: a modern graphical user interface for custom BLAST databases. Mol. Biol. Evol. 36:2922-2924. Sayers, E. W., Cavanaugh, M., Clark, K., Pruitt, K. D., Schoch, C. L., Sherry, S. T., and Karsch-Mizrachi, I. 2021. GenBank. Nucleic Acids Res. 49:D92-D96. Shivas, R. G., and Tan, Y. P. 2009. A taxonomic re-assessment of Colletotrichum acutatum, introducing C. fioriniae comb. et stat. nov. and C. simmondsii sp. nov. Fungal Divers. 39:111-122. Wharton, P., and Schilder, A. 2008. Novel infection strategies of Colletotrichum acutatum on ripe blueberry fruit. Plant Pathol. 57:122-134. Supplementary material Supplementary Figure 1: Isolation and identification of Colletotrichum fioriniae RGM 3330 from blueberry fruits cv. 'Brigitta Blue' from Chile. (A) A fruit showing anthracnose; (B) colony of Colletotrichum fioriniae RGM 3330 growing on PDA; (C) microscopic observation of the conidia (100x magnification; bar=10 µm); (D) phylogenetic tree resulting from a maximum likelihood analysis of combined sequence data from ITS, act, chs-1, gapdh, and tub regions for Colletotrichum acutatum species complex, number in the nodes represent ultrafast bootstrap values.

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BACKGROUND: The Generalized Anxiety Disorder 7-item (GAD-7) scale is widely used for the assessment of generalized anxiety disorder. AIM: To adapt the GAD-7 to the Chilean adolescent population and to evaluate its psychometric properties. MATERIAL AND METHODS: The GAD-7 was adapted and administered to 2,022 adolescents between 13 and 19 years of age, recruited from eight schools in the northern area of Santiago, Chile. Other self-report instruments were used to assess depressive symptoms and health-related quality of life. The one factor structure and invariance by sex were examined using Confirmatory Factor Analysis. Its reliability and validity based on its relationship with other variables were assessed. RESULTS: The one-factor structure and invariance by sex were confirmed. The results showed an adequate internal reliability (Cronbach's alpha = 0.86, Spearman-Brown coefficient = 0.82). As expected, significant correlations were observed with measures of depressive symptoms and health-related quality of life. Higher scores were observed in women than in men. CONCLUSIONS: The Chilean version adapted for adolescents of the GAD-7 has good psychometric properties. Thus, it may be a useful and valid instrument for the assessment of generalized anxiety disorder in adolescents in Chile.

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Black carbon (BC) from fossil fuel and biomass combustion darkens the snow and makes it melt sooner. The BC footprint of research activities and tourism in Antarctica has likely increased as human presence in the continent has surged in recent decades. Here, we report on measurements of the BC concentration in snow samples from 28 sites across a transect of about 2,000 km from the northern tip of Antarctica (62°S) to the southern Ellsworth Mountains (79°S). Our surveys show that BC content in snow surrounding research facilities and popular shore tourist-landing sites is considerably above background levels measured elsewhere in the continent. The resulting radiative forcing is accelerating snow melting and shrinking the snowpack on BC-impacted areas on the Antarctic Peninsula and associated archipelagos by up to 23 mm water equivalent (w.e.) every summer.

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Attributable to the Montreal Protocol, the most successful environmental treaty ever, human-made ozone-depleting substances are declining and the stratospheric Antarctic ozone layer is recovering. However, the Antarctic ozone hole continues to occur every year, with the severity of ozone loss strongly modulated by meteorological conditions. In late November and early December 2020, we measured at the northern tip of the Antarctic Peninsula the highest ultraviolet (UV) irradiances recorded in the Antarctic continent in more than two decades. On Dec. 2nd, the noon-time UV index on King George Island peaked at 14.3, very close to the largest UV index ever recorded in the continent. On Dec. 3rd, the erythemal daily dose at the same site was among the highest on Earth, only comparable to those recorded at high altitude sites in the Atacama Desert, near the Tropic of Capricorn. Here we show that, despite the Antarctic ozone recovery observed in early spring, the conditions that favor these extreme surface UV events persist in late spring, when the biologically effective UV radiation is more consequential. These conditions include long-lasting ozone holes (attributable to the polar vortex dynamics) that often bring ozone-depleted air over the Antarctic Peninsula in late spring. The fact that these conditions have been occurring at about the same frequency during the last two decades explains the persistence of extreme surface UV events in Antarctica.

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The chemical composition of snow provides insights on atmospheric transport of anthropogenic contaminants at different spatial scales. In this study, we assess how human activities influence the concentration of elements in the Andean mountain snow along a latitudinal transect throughout Chile. The concentration of seven elements (Al, Cu, Fe, Li, Mg, Mn and Zn) was associated to gaseous and particulate contaminants emitted at different spatial scales. Our results indicate carbon monoxide (CO) averaged at 20 km and nitrogen oxide (NOx) at 40 km as the main indicators of the chemical elements analyzed. CO was found to be a significant predictor of most element concentrations while concentrations of Cu, Mn, Mg and Zn were positively associated to emissions of NOx. Emission of 2.5 µm and 10 µm particulate matter averaged at different spatial scales was positively associated to concentration of Li. Finally, the concentration of Zn was positively associated to volatile organic compounds (VOC) averaged at 40 km around sampling sites. The association between air contaminants and chemical composition of snow suggests that regions with intensive anthropogenic pollution face reduced quality of freshwater originated from glacier and snow melting.

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Among the insect pests that affect crucifer crops in Mexico are Delia planipalpis (Meigen) and D. platura (Stein). They are a threat to the production of these vegetables since the damage they cause directly and indirectly affects yield, quality, and commercialization of these crops. Nevertheless, the existence of natural enemies of these dipterans is still unknown. It is fundamental to determine which parasitoids or predators can be considered possible biological control agents in an integrated pest management program. The sampling sites were located in Guanajuato, Puebla, and the State of Mexico, where plants of Brassica oleracea L. var. italica Plenk and capitata L., B. napus L., and Raphanus sativus L. infested with Delia spp. were selected. The symptoms observed were wilting, yellowish, flaccid leaves and individuals less developed than the rest of the crop. These plants were extracted with their root and the surrounding soil. Also, wild crucifers were collected, such as Raphanus raphanistrum L., Brassica campestris L., and Sisymbrium irio L. The first records of Aphaereta pallipes Say (Hymenoptera, Braconidae), Trybliographa rapae (Westwood) (Hymenoptera, Figitidae), and Aleochara bimaculata Gravenhorst (Coleoptera, Staphylinidae) are reported parasitizing the puparia of these anthomyiid flies on cultivated and wild crucifers. This represents only a starting point for the continuous study of these parasitoids, which is needed to consider them useful for the biological control of D. planipalpis and D. platura.

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Connexin hemichannels allow the unspecific but regulated interchange of molecules from ions to second messenger and ATP, between the eukariotic cell and its extracellular space. The transport of ions and water through hemichannels is important for physiological functions and also in the progression of several pathological conditions. Extracellular Ca2+ concentration is one of the regulators that drives the channel to a closed state. However the relation between their functional and structural states is far for being totally understood. In this work, we modelled connexin hemichannels using simple systems based on a fixed array of carbon atoms and assess the Ca2+ regulation using molecular dynamics simulations. The two proposed mechanism described so far for calcium action were studied combined, e.g., an electrostatic effect and a pore stretching. Our results show that the addition of positive charge density inside the channel cannot stop the flow of potassium, chloride nor water. Only a pore stretching at the center of the pore can explain the channel blocking.

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Psychotic experiences are prevalent in the general population and are associated with negative outcomes, including depressive symptoms. The mechanisms underlying this relationship remain unclear, but new insights could be obtained by exploring the role of transdiagnostic processes such as experiential avoidance, defined as a person's attempts or desires to suppress unwanted internal experiences like thoughts, emotions, memories, or bodily sensations. Studies analyzing the link between negative emotional states and psychotic experiences are scant. We explored the association between a specific kind of psychotic experience (paranoid ideation), experiential avoidance, and depressive, anxiety, and stress symptoms in a sample from the general population. We found that experiential avoidance partially mediates the associations between paranoid ideation and stress and anxiety symptoms and that it fully mediates the association between paranoid ideation and depressive symptoms. Our results suggest that the presence of paranoid ideation and the usage of experiential avoidance to cope with it are vulnerability factors associated with psychological distress.

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Resumen: Antecedentes: El Modelo Integrado Motivacional-Volitivo contempla la ideación suicida como una reacción psicológica a una situación que se percibe como una derrota junto a la percepción de estar atrapado/a y sin posible escape ni rescate. Objetivo: El presente estudio tiene como objetivo adaptar al contexto español y analizar las propiedades psicométricas de dos escalas, una para medir derrota y otra para medir atrapamiento. Método: Doscientas treinta y cuatro personas de 18-35 años (58,6% mujeres) completaron un cuestionario online. Resultados: El análisis de la estructura interna mostró una solución bifactorial para la escala de derrota y una solución unifactorial para la escala de atrapamiento, ambas con adecuados índices de ajuste. Además, mostraron buena fiabilidad de las puntuaciones de los test y evidencias favorables de validez. Conclusiones: Disponer de ambas escalas adaptadas contribuye a mejorar la evaluación del riesgo suicida, así como a orientar la intervención y realizar aportaciones en el campo de la suicidología.

Abstract: Background: The Integrated Motivational-Volitional Model contemplates suicidal ideation as a psychological reaction to a situation that is perceived as a defeat along with the perception of being trapped and without possible escape or rescue. Aim: The present study aims to adapt to the Spanish context and analyze the psychometric properties of two scales, one to measure defeat and another to measure entrapment. Method: Two hundred and thirty-four people aged 18-35 years (58.6% women) completed an online questionnaire. Results: The analysis of the internal structure showed a bifactorial solution for the scale of defeat and a unifactorial solution for the scale of entrapment, both with adequate adjustment indexes. In addition, they showed good reliability of the test scores and favorable evidence of validity. Conclusions: Having both scales adapted helps to improve the assessment of suicide risk, as well as to guide the intervention and make contributions in the field of suicide.

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RESUMO

Predicting radiative forcing due to Antarctic stratospheric ozone recovery requires detecting changes in the ozone vertical distribution. In this endeavor, the Limb Profiler of the Ozone Mapping and Profiler Suite (OMPS-LP), aboard the Suomi NPP satellite, has played a key role providing ozone profiles over Antarctica since 2011. Here, we compare ozone profiles derived from OMPS-LP data (version 2.5 algorithm) with balloon-borne ozonesondes launched from 8 Antarctic stations over the period 2012-2020. Comparisons focus on the layer from 12.5 to 27.5 km and include ozone profiles retrieved during the Sudden Stratospheric Warming (SSW) event registered in Spring 2019. We found that, over the period December-January-February-March, the root mean square error (RMSE) tends to be larger (about 20%) in the lower stratosphere (12.5-17.5 km) and smaller (about 10%) within higher layers (17.5-27.5 km). During the ozone hole season (September-October-November), RMSE values rise up to 40% within the layer from 12.5 to 22 km. Nevertheless, relative to balloon-borne measurements, the mean bias error of OMPS-derived Antarctic ozone profiles is generally lower than 0.3 ppmv, regardless of the season.