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The walnut industry in Argentina has grown in recent years, especially in northern Patagonia. However, this expansion has also brought new challenges, including the emergence of diseases threatening the health and productivity of walnut plantations. One of the most important diseases affecting walnut crops worldwide is 'ink disease' or 'walnut dieback'. The aim of this study was to characterize ink disease, identify the aetiological agents, and estimate its incidence in walnut orchards of northern Patagonia, Argentina. Symptomatic trees were observed in the seven surveyed walnut orchards, showing a range of symptoms, including chlorosis and wilting, stem cankers and desiccation. In vivo assay and molecular analyses revealed that not only Phytophthora (P.) but also Phytopythium (Ph.) species are the causal agents of the disease, with P. drechsleri, Ph. mercuriale and Ph. vexans being the most virulent over the commonly used rootstock Juglans hindsii. Notably, Ph. vexans was the most frequently isolated pathogen, suggesting its prevalence and potential impact on the regional walnut industry. Overall, this study provides critical insights into the prevalence and impact of Phytophthora and Phytopythium species on walnut health in northern Patagonia. The presence of multiple pathogenic oomycete species raises concerns about the health of walnut orchards, as well as the potential risk of pathogen transmission to other fruit crops in the region. The findings will help growers to develop better cultural practices and implement measures to guarantee the sustainability of the walnut industry in Patagonia. [ABSTRACT FROM AUTHOR]

Although the estimated prevalence of ADHD in the school population is 5%, various studies carried out in Latin America have obtained higher figures. This descriptive‐cross‐sectional research analysed the prevalence of ADHD symptomatology in a random and probabilistic sample of 1535 schoolchildren from Cuenca‐Ecuador (aged from 72 to 164 months, 51.3% were female and 50% attended public schools). IQ was evaluated using the Raven's Progressive Matrices Test. The ADHD symptomatology was evaluated using the short version of Conners‐3. Descriptive statistics, chisquares and prevalence data were calculated. We found a total prevalence of ADHD symptomatology of 20.3%. A higher prevalence of ADHD symptomatology was reported among girls compared to boys; and in public schools (compared to private schools). These findings may reflect a higher occurrence of ADHD in vulnerable populations that tend to be less well cared for. Although the results do not come from complete individual clinical evaluations, the representativeness of the sample and the simultaneous presence of scores above the cut‐off points in the home and school contexts show a worrying situation that should be taken into account by agents responsible for the design of public health and education policies. [ABSTRACT FROM AUTHOR]

Over the past decade, we have conducted geochemical and isotopic monitoring of the fumarolic gases of the Peteroa volcano (Argentina‐Chile). Using the resulting data set, we constructed a conceptual model that describes the evolution of the magmatic‐hydrothermal system and identifies precursory geochemical signals of the last eruption. Our data set includes new chemical and isotopic analyses of fumarolic gas samples collected from 2016 to 2021, as well as previously published data from the 2010–2015 period. After an eruptive period in 2010–2011, the activity was characterized by low degassing rates and seismic activity. However, an increase in seismic activity and fumarolic gas emissions was observed from 2016 to 2018–2019 eruptive episode, leading to a major phreato‐magmatic eruption. Fumarole gases show different compositions during quiescent versus unrest/eruptive degassing related to the interaction of deep (magmatic) and shallow (hydrothermal) fluid contributions. During quiescent periods, fumaroles exhibited low SO2/H2S, HF/CO2, and HCl/CO2 ratios (<0.1), revealing a dominant hydrothermal contribution. In contrast, during pre‐and syn‐eruptive periods, fumaroles showed ratios up to 100 times higher indicative of an enhanced magmatic input. When compared to the evolution of the seismic activity, the increment of magmatic‐related strong acidic gases suggests repeated inputs of hot magmatic fluids, which are only partially dissolved into the hydrothermal system feeding the fumaroles. Interestingly, the 3He/4He and δ13C‐CO2 values remained relatively constant during the magmatic and hydrothermal degassing in 2016–2021, suggesting that the deep magmatic gas source did not significantly change throughout variations in Peteroa's activity.Plain Language Summary: The Peteroa volcano is an active volcano located in the southern Andes Mountains of South America. It has erupted multiple times in recent years, but there is limited knowledge about its behavior and potential damage it could cause. To address this, we have been studying the volcano for the past decade using special techniques to examine the gases that come out of the openings in the ground, known as fumaroles. These fumaroles allow volcanic gases to escape, and by collecting data on fumarolic gas samples from 2010 to 2021, we have developed a model that helps us understand how the volcano changes over time and identify warning signs of an upcoming eruption. Our research found increased seismic activity and fumarolic gas emissions starting in 2016, leading to a significant eruption from 2018 to 2019. We also discovered that the composition of the fumarolic gases varies depending on whether the volcano is in a quiet or unrest period. During quiet periods, the gases show compositions with a stronger influence from underground water, but before and during the 2018–2019 eruption, the gas compositions showed changes indicating a more significant influence of magma. This study is vital as it enhances our understanding of volcano behavior and provides valuable insights for forecasting future eruptions. This is particularly important in the region as there are many potentially dangerous volcanoes with limited available information, but the findings can be applied to improve our understanding of other volcanoes, ultimately contributing to the global knowledge base on volcanic processes.Key Points: Geochemical and isotopic monitoring of Peteroa volcano allowed us to elaborate a conceptual model that explains the evolution of the magmatic‐hydrothermal systemFumarolic gases exhibit different compositions during quiescent and unrest/eruptive periods, allowing the identification of precursory signals of the last eruptionDespite variations in activity, the deep magmatic gas source of Peteroa volcano remained relatively constant, as indicated by consistent He and C isotopic values [ABSTRACT FROM AUTHOR]

This study examined whether protected land in a tropical reservoir's catchment can promote the survival of native aquatic plants (macrophytes) and limit the spread of invasive alien plant species (macrophyte IAS), which can threaten native wildlife and require expensive remediation. As the number of tropical river dams is expected to increase in the coming decades to meet societal demands, it is crucial to explore solutions for preserving aquatic biodiversity.The study used a before–after–control–intervention design, based on monitoring data and long‐term sedimentological, climatic and ecological records from both lake and river zones adjacent to protected and unprotected lands around the 100‐year‐old Gatun Lake in the Panama Canal, Panama. The research examined the impact of impoundment and the invasion of Pontederia crassipes (water hyacinth) and Hydrilla verticillata (water thyme) on native macrophyte communities and environmental variables.Lake zones adjacent to protected lands had lower nutrient concentrations, greater variations in water depth profiles and reduced fluctuations in water chemistry than lake zones outside areas of land protection. In addition, the results showed that whereas zones adjacent to unprotected land became dominated by macrophyte IAS, lake zones adjacent to protected areas were more resilient to the spread of macrophyte IAS and were able to maintain viable populations of native pre‐dam species for >100 years.This study indicates that protecting land adjacent to tropical reservoirs could be a cost‐effective solution for preserving aquatic macrophyte biodiversity by retaining nutrients, stabilizing water chemistry, providing habitat heterogeneity and protecting native vegetation, while still supporting terrestrial conservation goals. These findings could aid in planning measures for the hundreds of proposed dam projects across lowland tropical areas and provide new insights into best practices for enhancing river ecosystem resilience. [ABSTRACT FROM AUTHOR]

The Magdalena River in Colombia is one of the world's largest (discharge = 7100 m3 s−1) tropical rivers, hosting > 170 aquatic vertebrate species. However, concise synthesis of the current ecological and environmental status is lacking. By documenting the anthropogenic stressors impacting the river on time scales ranging from centuries to decades, we found that the river system is subject to the compounding impacts of climate change, river impoundment, invasive alien species (IAS), catchment deforestation, and water pollution. We show that the Magdalena is a woefully understudied ecosystem relative to its critical importance to Colombia's economy, culture, and biodiversity compared with other similarly sized tropical rivers. We emphasize the need for research on (1) IAS population and ecological dynamics, (2) river damming and its links with IAS and climate change, and (3) land‐use changes as well as identifying sources of water pollution and strategies for mitigation. [ABSTRACT FROM AUTHOR]

This study presents the long‐term evolution of two floodplains lakes (San Juana and Barbacoas) of the Magdalena River in Colombia with varying degree of connectivity to the River and with different responses to climate events (i.e., extreme floods and droughts). Historical limnological changes were identified through a multiproxy‐based reconstruction including diatoms, sedimentation, and sediment geochemistry, while historical climatic changes were derived from the application of the Standardised Precipitation‐Evapotranspiration Index. The main gradients in climatic and limnological change were assessed via multivariate analysis and generalized additive models. The reconstruction of the more isolated San Juana Lake spanned the last c. 500 years. Between c. 1,620 and 1,750 CE, riverine‐flooded conditions prevailed as indicated by high detrital input, reductive conditions, and dominance of planktonic diatoms. Since the early 1800s, the riverine meander became disconnected, conveying into a marsh‐like environment rich in aerophil diatoms and organic matter. The current lake was then formed around the mid‐1960s with a diverse lake diatom flora including benthic and planktonic diatoms, and more oxygenated waters under a gradual increase in sedimentation and nutrients. The reconstruction for Barbacoas Lake, a waterbody directly connected to the Magdalena River, spanned the last 60 years and showed alternating riverine–wetland–lake conditions in response to varying ENSO conditions. Wet periods were dominated by planktonic and benthic diatoms, while aerophil diatom species prevailed during dry periods; during the two intense ENSO periods of 1987 and 1992, the lake almost desiccated and sedimentation rates spiked. A gradual increase in sedimentation rates post‐2000 suggests that other factors rather than climate are also influencing sediment deposition in the lake. We propose that hydrological connectivity to the Magdalena River is a main factor controlling lake long‐term responses to human pressures, where highly connected lakes respond more acutely to ENSO events while isolated lakes are more sensitive to local land‐use changes. [ABSTRACT FROM AUTHOR]

An increasing number of microRNAs (miRNAs) and miRNA‐related sequences produced during miRNA biogenesis, comprising the isomiRome, have been recently highlighted in different species as critical mediators of environmental stress responses. Conifers have some of the largest known genomes but an extensive characterization of the isomiRome from any conifer species has been lacking. We provide here a comprehensive overview of the Pinus pinaster isomiRome expressed in roots, stem and needles under well‐watered and drought conditions. From the 13,441 unique small RNA sequences identified, 2,980 were annotated as canonical miRNAs or miRNA* and the remaining were classified as isomiRNA or miRNA‐like sequences. A survey of their expression patterns highlighted roots as the most responsive organ under drought, where specific sequences of which a 24‐nt novel miRNA stood out, were strongly down‐regulated. Given the putative roles of the miRNA‐targeted transcripts validated specifically in root tissues, some of the miRNAs, conserved and novel, are shortlisted as potential regulators of drought response. These results provide a valuable resource for comparative studies between gymnosperms and angiosperms. Furthermore, it evidences high transferability of the isomiRome between pine species being a useful basis for further molecular regulation and physiological studies, and especially those focused on adaptation to drought conditions. The present work provides a first characterization of the rich and variable isomiRome encoded by a conifer genome. Results highlight a differential distribution of the isomiRome in different vegetative organs and under contrasting water availability, and potentially targeting transcripts controlling key physiological responses to drought. [ABSTRACT FROM AUTHOR]

Adaptation of long‐living forest trees to respond to environmental changes is essential to secure their performance under adverse conditions. Water deficit is one of the most significant stress factors determining tree growth and survival. Maritime pine (Pinus pinaster Ait.), the main source of softwood in southwestern Europe, is subjected to recurrent drought periods which, according to climate change predictions for the years to come, will progressively increase in the Mediterranean region. The mechanisms regulating pine adaptive responses to environment are still largely unknown. The aim of this work was to go a step further in understanding the molecular mechanisms underlying maritime pine response to water stress and drought tolerance at the whole plant level. A global transcriptomic profiling of roots, stems, and needles was conducted to analyze the performance of siblings showing contrasted responses to water deficit from an ad hoc designed full‐sib family. Although P. pinaster is considered a recalcitrant species for vegetative propagation in adult phase, the analysis was conducted using vegetatively propagated trees exposed to two treatments: well‐watered and moderate water stress. The comparative analyses led us to identify organ‐specific genes, constitutively expressed as well as differentially expressed when comparing control versus water stress conditions, in drought‐sensitive and drought‐tolerant genotypes. Different response strategies can point out, with tolerant individuals being pre‐adapted for coping with drought by constitutively expressing stress‐related genes that are detected only in latter stages on sensitive individuals subjected to drought. [ABSTRACT FROM AUTHOR]

Since 2015, Araucaria araucana, an ecologically and economically important conifer native to Argentina and Chile, has suffered an unusual partial death of the crown throughout almost all of the distribution range in Argentina. No primary pathogen or pest was evident, associated with the phenomenon. Isolates of Mortierella, a poorly studied fungal genus in Patagonia, were obtained from the margins of necrotic phloem tissue of symptomatic trees. Five species of Mortierella were isolated from affected tissues. In inoculation tests, Mortierella alpina and M. aff. basiparvispora were pathogenic to A. araucana. These species caused necrosis of phloem, leading to chlorosis, foliar desiccation and eventually death, demonstrating that Mortierellales may play a role in the decline of the tree. [ABSTRACT FROM AUTHOR]

Block copolymers offer the fabrication of mesoporous thin films with distinct nanoscale structural features. In this contribution, we present the use of acetic acid (CH3COOH) as a low‐molecular‐weight guest molecule to tune the supramolecular assembly of poly[styrene‐block‐(4‐vinylpyridine)] (PS‐b‐P4VP), offering a versatile and straightforward method to obtain tailored nanostructured films with controlled topography and pore size. Spin‐coating toluene solutions of PS‐b‐P4VP, with a variable amount of CH3COOH, leads to micellar thin films, where the micelles contain the carboxylic acid as a guest molecule. The size can be conveniently modified in these films (from 48 to 75 nm) by varying the amount of organic acid in the starting solutions. Subsequent surface reconstruction of micellar films using ethanol leads to ring‐shaped copolymer nanoporous films with modulated diameter. Controlling the micelle reconstruction process, cylindrical porous films are also obtained. Interestingly, changing the type of aliphatic carboxylic acid leads to a modification of the observed film morphology from micelles to out‐of‐plane P4VP cylinders (or lamellae) in a PS matrix. © 2019 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

Abstract: Many invasive plant species have fleshy fruits that are eaten by native frugivorous birds which disperse their seeds and may facilitate their germination, playing an important role in plant invasion success. The fleshy‐fruited shrub Cotoneaster franchetii (Rosaceae) is an important invasive alien in the mountainous regions of central Argentina. To determine the role of avian frugivorous in fruit removal of this species, we conducted a frugivore exclusion experiment including bagged and unbagged branches in 75 plants of C. franchetii. At the end of the dispersal period, we compared the percentage of missing fruits (removed by birds + naturally dropped) in unbagged branches with the percentage of naturally dropped fruits in bagged branches. To assess whether any mechanism acting on seeds during their passage through bird guts (de‐inhibition by pulp removal and/or seed scarification) affects seed germination of this species, we compared percentage and speed of germination among seeds obtained from faeces of the native frugivorous Turdus chiguanco, from manually de‐pulped fruits, and from intact fruits. The percentage of missing fruits per shrub in unbagged branches was significantly higher than the percentage of naturally dropped fruits in bagged branches, suggesting that frugivorous birds play an important role in fruit removal of C. franchetii in the study area. Seeds from bird faeces and from manually de‐pulped fruits germinated in higher percentage and faster than seeds from intact fruits. Germination percentage and speed of seeds from manually de‐pulped fruits were significantly higher than those of gut‐passed seeds. These results indicate that T. chiguanco increases and accelerates seed germination of C. franchetii through pulp removal, but not through seed scarification. Overall, our findings indicate that native frugivorous birds facilitate the dispersal and germination success of C. franchetii, likely playing an important role in its invasion throughout the mountainous region of central Argentina. [ABSTRACT FROM AUTHOR]

Abstract: Films of four different nanostructures, namely micelles, filled cylinders, ring‐shaped porous nanostructures and hollow cylinders, can be prepared easily in a straightforward and simple way by spin coating onto a silicon plate toluene solutions of poly(styrene‐block‐4‐vinylpyridine) copolymer containing formic acid of increasing concentration. Despite the enormous progress in preparation of porous polymers, most of them require multiple steps. In this sense, this method represents an effort to obtain not only porous thin films but also other bidimensional nanostructures in a very simple way. © 2017 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

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R6372 --> 805.13 --> The severe acute respiratory syndrome‐ 2 (SARS‐CoV‐2) caused the coronavirus disease COVID‐19 responsible for the current pandemic presenting a high mortality rate. The development of vaccines provided a transient relief to the social, economic, and health care systems. However, the virus is constantly mutating to survive, generating new pathogenic variants that jeopardize the ongoing efforts and up‐to‐date accomplishments against it. The TMPRSS2 is a crucial player for SARS‐CoV‐2 cell entry. This transmembrane serine protease intervenes with the viral Spike/Angiotensin‐Converting Enzyme 2 (ACE2) host receptor axis, enabling to initiate the SARS‐CoV‐2 entry to target cells. The subsequent viral replication causes pathophysiological changes including a major complication of the COVID‐19 known as the inflammatory storm (IS). This is characterized by an enhanced release of inflammatory modulators leading to a hyper‐inflammation. TMPRSS2 is expressed in the epithelial cells of several tissues, including the epithelium of the respiratory tract, that is the focus of our study. However, this catalytic enzyme shows poor anchoring in the cell membrane and is consequently released into the extracellular space with the potential to activate or cleave neighboring cells dependent on serine proteases. An example of this cellular scenario is represented by the Protease Activated Receptor‐2 (PAR‐2), associated with activation of inflammatory pathways upon cleavage of the N‐terminus by a serine protease. We hypothesized: 1) that TMPRSS2 co‐localizes with PAR‐2 at the cell membrane of target epithelial cells; 2) TMPRSS2 activates PAR‐2 and associated proinflammatory signaling pathways; 3) the SARS‐CoV‐2 chaotic inflammation together with PAR‐2 activation will worsen the resulting IS. Based on our lab prior work on PAR‐2 and its antagonist, we anticipate that by inhibiting PAR‐2 activation, we will observe a decrease in the COVID‐19 associated IS. In this study, we used the MCF‐7 cell line to standardize the protocols, since this cell line expresses both proteins. They are more resilient to adverse conditions in the lab (due to the pandemic consequences at research labs) and will allow us to establish a proof of concept to be compare with the human primary airway epithelial cells that we will subsequently use. Using MCF‐7 as a model, we established the presence of PAR‐2 and TMPRSS2 via western blot. In addition, by using immuno‐cyto‐fluorescence we confirmed that these two proteins colocalize at the cell membrane. Activation of intracellular calcium‐dependent pathways, detected by intracellular calcium fluorogenic assay, showed that after treating cells with trypsin (Gold Standard for PAR‐2 activation), TMPRSS2, PAR‐2 agonist, and PAR‐2 antagonist, trypsin caused a significant (p < 0.05) increase compared to TMPRSS2 either alone, with the PAR‐2 agonist or the PAR‐2 antagonist with a decreasing of 50 % trypsin activity. Importantly, BrdU assay results showed that PAR‐2 antagonist decreased the proliferation of MCF‐7 cells when compared to trypsin (p < 0.005). Currently, we are working to test our hypothesis with human primary cells from different locations of the respiratory tract and compare the outcomes with the MCF‐7 model. Furthermore, our study will contribute to having a better understanding of PAR‐2 role in SARS‐ CoV‐2 complications. [ABSTRACT FROM AUTHOR]

An essay is presented on the potential of capital investments to improve neighborhood well-being in communities. The author cites a study that offers broad perspective on political economy and public social control by focusing on the relationship between capital investment and neighborhood crime. He also encourages the need for policy makers to shift attention from individual residents to policy decisions that will promote good ties between neighborhoods and city elites.

Through a longitudinal case study, this article examines the evolution of the twofold function of formal governance mechanisms, for control and coordination, as an interorganizational relationship evolves. We ask whether all formal governance tools develop simultaneously, or whether each mechanism is designed and used for only one function; whether different mechanisms' attributes foster one function rather than the other; and whether different mechanisms are developed over time in order to provoke both functions' evolution. Finally, we explore whether the interorganizational relationship evolution in part explains the evolution of the two functions, or vice versa. Copyright © 2012 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Despite significant advances in the study of neighborhoods and crime, criminologists have paid surprisingly less attention to the extralocal forces that shape violence. To address this issue, we draw on an emerging body of work that stresses the role of home mortgage lending-a resource secured via interaction with external actors-in reducing neighborhood violence and extend it by addressing concerns that the lending-violence relationship is spurious and confounded by simultaneity. We explore the longitudinal relationship between residential mortgage lending and violence in Seattle with a pooled time series of 118 census tracts over 27 years, and we instrument our endogenous predictors (home mortgage lending and violent crime) with changes in their levels from prior periods. Employing Arellano-Bond difference models, we assess both the effect of mortgage lending on violent crime as well as the effect of violent crime levels on mortgage activity. We find that infusions of home mortgage lending yield reductions in subsequent violent crime; yet the impact of violent crime on subsequent lending is not significant. Results underscore the importance of incorporating external forces such as home mortgage lending into explanations of neighborhood violence. [ABSTRACT FROM AUTHOR]

The aim of this work was to identify a treatment on milk fat, applicable to pretreat cheese milk, which could enhance lipolysis. Three factors were studied in milk fat mixtures: physical treatment (pumping and mechanical agitation), temperature (5, 15, and 45°C) and fat content (5%, 15%, and 30%). Damage to fat globule was estimated by assessing free fat and by phase contrast microscopy. Moderate damage was achieved in a mixture of 30% of fat, treated with mechanical agitation at 2800 rpm/2 min at 5°C. Applying this procedure to prepare minicurds did not modify values of fat content, moisture and lipolysis. [ABSTRACT FROM AUTHOR]

This paper examines the relationship between race and violent crime by directly modeling the racial gap in homicide offending for large central cities for 1990. We evaluate the role of black-white differences in aspects of both disadvantage and resources in explaining which places have wider racial disparities in lethal violence. The results show that where residential segregation is higher, and where whites' levels of homeownership, median income, college graduation, and professional workers exceed those for blacks to a greater degree, African Americans have much higher levels of homicide offending than whites. Based on these results, we conclude that the racial homicide gap is better explained by the greater resources that exist among whites than by the higher levels of disadvantage among blacks. [ABSTRACT FROM AUTHOR]

This study introduces public social control into multilevel victimization research by investigating its impact on household and personal victimization risk for residents across 60 urban neighborhoods. Public social control refers to the ability of neighborhoods to secure external resources necessary for the reduction of crime and victimization. I find that living in neighborhoods with high levels of public social control reduces an individual's likelihood of victimization, especially in disadvantaged neighborhoods. Given the important role that residents of disadvantaged neighborhoods can play in securing public social control, this contingent finding suggests that disadvantaged neighborhoods can be politically viable contexts. [ABSTRACT FROM AUTHOR]

Phytophthora austrocedri is a pathogen of Austrocedrus chilensis causing "Mal del Ciprés" (cypress sickness) in Patagonia and killing Juniperus communis in Britain, along with other species in the Cupressaceae. The evident association of the pathogen with members of the Cupressaceae makes it necessary to study the susceptibility of other species related to A. chilensis to prevent the emergence of new diseases. The present study tested the pathogenicity of P. austrocedri to three native and endemic conifers in South America: Fitzroya cupressoides, Pilgerodendron uviferum and Araucaria araucana. The results showed that F. cupressoides and P. uviferum were highly susceptible to P. austrocedri. Since these are endangered tree species, the outcome of this study is crucial for governmental agencies, policymakers and stakeholders. [ABSTRACT FROM AUTHOR]