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The quality and quantity of clozapine safety monitoring considerably differs among South American countries and mainly focus on hematological surveillance. Few studies have been conducted on other clozapine-related adverse effects (ADRs) and mainly refer to case reports and literature reviews. We retrieved thirty-nine publications on clozapine related ADRs others than neutropenia. Studies in Brazil and Venezuela accounted for 67 % of all the publications, and 8 out of 12 countries published 2 or less manuscripts. Only Chile offers serum clozapine level measurement in public institutions. Given the recently recognized role of ethnicity, gender, smoking, obesity drug interactions in optimal clozapine administration, modernization of clozapine clinical use and research in psychiatry and neurology most be broadcasted and stimulated in South American countries. [ABSTRACT FROM AUTHOR]

• Von Willebrand disease is the most common inherited bleeding disorder • The spectrum of novel mutations found mirrors the multi-ethnicity in Venezuela. • Our work emphasizes the importance of VWF multimer and genetic analysis for the appropriate classification of VWD. [ABSTRACT FROM AUTHOR]

The pathogen Paracoccidioides lutzii (Pb01) is found in South America countries Colombia, Ecuador, Venezuela and Brazil, especially in the central, west, and north regions of the latter. It belongs to the Ajellomycetaceae family, Onygenales order, and is typically thermodimorphic, presenting yeast cells when it grows in animal tissues, but mycelia when in the environment, where it produces the infectious propagule. This fungus is one of the etiologic agents of Paracoccidioidomycosis (PCM), the most important endemic fungal infection in Latin America. Investigations on its genome have contributed to a better understanding about its metabolism and revealed the complexity of several metabolic glycolytic pathways. Glyceraldehyde-3-Phosphate Dehydrogenase from Paracoccidioides lutzii (Pl GAPDH) is considered a moonlighting protein and participates in several biological processes of this pathogen. The enzyme was expressed and purified, as seen in SDS-PAGE gel, crystallized and had its three dimensional structure (3D) determined in complex with NAD+, a sulphate ion and d -galactonic acid, therefore, a type of 'GAA site'. It is the first GAPDH structure to show this chemical type in this site and how this protein can bind an acid derived from oxidation of a linear hexose. [Display omitted] • A new ligand (d -Galactonic Acid) in complex with GAPDH. • First observation of an aldonic sugar acid (GAA) or a hexose derived acid in complex with GAPDH. • Unique hydrophilic stretch (HSSSNN) holds potential for targeted inhibitor design. [ABSTRACT FROM AUTHOR]

NRAMP1 and VDR gene polymorphisms have been variably associated with susceptibility to tuberculosis (TB) amongst populations having different genetic background. NRAMP1 and VDR gene variants' association with susceptibility to active infection by Mycobacterium tuberculosis (Mtb) was analyzed in the Warao Amerindian population, an ethnic population from Venezuela's Orinoco delta region. Genomic DNA was extracted from individuals with and without TB to evaluate genetic polymorphism by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). Four NRAMP1 gene polymorphisms were analyzed: D543N (rs17235409), 3′ UTR (rs17235416), INT4 (rs3731865), and 274C/T (rs2276631), and one VDR gene polymorphism: FokI (rs2228570). The results showed that the genotypes D543N-A/A, 3′UTR-TGTG+/+, INT4-C/C, and 274C/T-T/T of known polymorphism in the NRAMP1 gene, as well as the genotypes FokI-F/f and FokI-f/f in the VDR gene were most often found in indigenous Warao with active TB. Binomial logistic regression was used for evaluating associations between polymorphisms and risk of contracting TB, an association between NRAMP1- D543N-A/A genotype distribution and TB susceptibility was found in Warao Amerindians. Regarding Venezuelan populations having different genetic backgrounds; statistically significant TB associations concerning NRAMP1 -D543N-A/A, INT4-C/C and 3′UTR-TGTG+/+ variant genotype distributions in Warao Amerindians (indigenous) compared to Creole (admixed non-indigenous population) individuals were found. In conclusion, the results thus indicated that the association between NRAMP1- D543N-A/A genotype and TB in Warao Amerindians could support such allele's role in host susceptibility to Mtb infection. [ABSTRACT FROM AUTHOR]

To assess the effect of hydroxychloroquine (HCQ) and Tenofovir disoproxil fumarate/emtricitabine (TDF/FTC) as pre-exposure prophylaxis on COVID-19 risk. EPICOS is a double-blind, placebo-controlled randomized trial conducted in Spain, Bolivia, and Venezuela. Healthcare workers with negative SARS-CoV-2 IgM/IgG test were randomly assigned to the following: daily TDF/FTC plus HCQ for 12 weeks, TDF/FTC plus HCQ placebo, HCQ plus TDF/FTC placebo, and TDF/FTC placebo plus HCQ placebo. Randomization was performed in groups of four. Primary outcome was laboratory-confirmed, symptomatic COVID-19. We also studied any (symptomatic or asymptomatic) COVID-19. We compared group-specific 14-week risks via differences and ratios with 95% CIs. Of 1002 individuals screened, 926 (92.4%) were eligible and there were 14 cases of symptomatic COVID-19: 220 were assigned to the TDF/FTC plus HCQ group (3 cases), 231 to the TDF/FTC placebo plus HCQ group (3 cases), 233 to the TDF/FTC plus HCQ placebo group (3 cases), and 223 to the double placebo group (5 cases). Compared with the double placebo group, 14-week risk ratios (95% CI) of symptomatic COVID-19 were 0.39 (0.00–1.98) for TDF + HCQ, 0.34 (0.00–2.06) for TDF, and 0.49 (0.00–2.29) for HCQ. Corresponding risk ratios of any COVID-19 were 0.51 (0.21–1.00) for TDF + HCQ, 0.81 (0.44–1.49) for TDF, and 0.73 (0.41–1.38) for HCQ. Adverse events were generally mild. The target sample size was not met. Our findings are compatible with both benefit and harm of pre-exposure prophylaxis with TDF/FTC and HCQ, alone or in combination, compared with placebo. [ABSTRACT FROM AUTHOR]

Venezuela's social and economic crisis of the past eight years has had an impact on healthcare services. However, because Venezuela has traditionally been thought to be a country with low levels of racism, it has been assumed that mental health nurses' satisfaction is the same across ethnic groups. The present study tests that hypothesis. Results come out showing that, as compared to whites, mental health nurses of color in Venezuela have lower levels of job satisfaction, and higher levels of perceived ethnic discrimination. Results also show that amongst mental health nurses of color in Venezuela, perceived ethnic discrimination and job satisfaction are negatively correlated. • Mental health nurses of color in Venezuela present low levels of job satisfaction. • Lower satisfaction levels at work are correlated with higher levels of perceived ethnic discrimination. • Policymakers in Venezuela must consider ways to protect mental health nurses of color from suffering ethnic discrimination. [ABSTRACT FROM AUTHOR]

The loss of hydrological connectivity and fragmentation of natural wetlands are widespread drivers of wetland degradation. Understanding where and how natural connectivity is impaired is essential for managing, protecting and remediating these ecosystems. Wetland Interferometric Synthetic Aperture Radar (Wetland InSAR) can provide information on surface flow orientation in wetlands at a high spatial resolution, which can be used for the detection of hydrological barriers in the wetland. However, the broad application of this approach is constrained by the labour-intensive manual delineation of barriers based on mapped water levels. This study presents the first deep learning-based methodology for the automated detection of hydrological barriers. We trained a deep convolutional network to segment edge features of hydrological barriers in 22 image pairs captured by ALOS PALSAR-1 L-Band InSAR between 2006 and 2011. The training dataset consisted of manually labelled and delineated barriers showing abrupt changes in water surface elevation and wrapped interferograms with high coherence. The model was trained and tested on six wetland sites of varying fragmentation levels and wetland types in the United States, Cuba, Mexico, Colombia and Venezuela. Across these sites, the convolutional network detected hydrological barriers with up to 80% accuracy. The model performed particularly well in detecting linear hydrological barriers such as roads, levees and channels. Notably, we found that some barriers impede flow only seasonally, appearing during low water levels and disappearing when water levels rise. However, the model shows limitations in detecting barriers in highly dynamic environments with lower coherence. Our automated approach to detecting and assessing wetland hydrologic connectivity can be applied more broadly to support the effective management of fragmented wetland ecosystems. • Successful detection of hydrologic barriers by combining InSAR with Deep Learning. • Uniform model performance across wetland types, achieving up to 80% accuracy. • Model is capable of capturing barriers hidden in optical satellite imagery. • Approach facilitates detection of seasonal variations in wetland fragmentation. [ABSTRACT FROM AUTHOR]

• We measured RBD-IgG levels in Sputnik V vaccinated 6 months after vaccination. • The GMT of RBD-IgG antibodies in a COVID-19 naïve cohort was 327 BAU/ml. • The GMT of RBD-IgG antibodies in previously infected people was 910 BAU/ml. • 94% of both cohorts had a good to excellent neutralizing activity in an in vitro test. • The Sputnik V vaccine induced a long-lasting immune response of at least 6 months Scarce information is available regarding the long-term immunogenicity of the Sputnik V vaccine. Here Sputnik V vaccinated subjects were evaluated 6 months after receiving the 2-dose prime-boost schedule. Eighty-six hospital workers from Venezuela, 32 with a previous COVID-19 infection and 54 SARS-CoV-2 naïve subjects, were enrolled. IgG antibodies levels against the wild-type Receptor Binding Domain (RBD) were measured in an ELISA and with an in vitro ACE2-surrogate RBD binding inhibition assay at day 42 and day 180 after receiving the second dose. IgG levels were expressed in BAU/ml. Binding inhibition antibodies were expressed in IU/ml. On average, RBD-IgG levels decreased by approximately 50% between the two time-points in the COVID-19 naïve cohort (geometric mean concentration (GMC) 675 BAU/mL vs. 327 BAU/ml) and decreased by approximately 25% in the previously infected cohort (GMC 1209 BAU/mL vs 910 BAU/ml). Within our cohort, 94% showed a "good to excellent" neutralizing activity measured with the in vitro test 6 months after vaccination. The Sputnik V vaccine provided long-term and durable humoral immunity in our cohort specially if a person has been both vaccinated and had a previous infection with SARS-CoV-2. [ABSTRACT FROM AUTHOR]

Background: The current practice of child neurology in Latin America has been impacted by the waves of sociopolitical unrest that in the last decades have swept the region.Methods: We searched the available literature referring to the situation of child neurology in Latin America and conditions that specifically impact the region.Results: In lower-middle-income countries, the number of child neurologists is inadequate. Child neurologists working in large public hospitals can only afford to do so on a part-time basis as these institutions are chronically underfunded. Several circumstances are particularly relevant to Latin America: Spanish is the main language spoken, something that limits the opportunity to keep local child neurologists up to date. The structure of health care systems in Latin America varies significantly. Some countries have fragmented systems with inadequate capacity to offer equitable access to medical care. Latin America has been impacted by epidemics of arthropod-borne viruses: zika, chikungunya, and dengue. It stands to reason that the COVID-19 pandemic will affect the distribution of resources for chronic neurological conditions.Conclusions: The virtual platforms such as Zoom, expanded during the COVID-19 pandemic, are useful not only to improve access to care through telemedicine but also for educational purposes. Collaborative efforts to support educational courses and symposia in Spanish are ongoing. It is necessary to set short- and long-term priorities to improve child neurology care in the region. Immediate priorities should focus on improving the diagnosis of neurological conditions, making emphasis on locally available resources. [ABSTRACT FROM AUTHOR]

Tradicionalmente, la calidad de vida relacionada con la salud (CVRS) de los pacientes con lupus eritematoso sistémico (LES) ha sido evaluada utilizando instrumentos que desatienden las características específicas de la enfermedad. Este estudio determina la validez del cuestionario Lupus Quality of Life (LupusQoL) como instrumento psicométricamente estable para medir la CVRS de los pacientes con LES en Venezuela, y establece los puntos de corte del cuestionario para la población venezolana. Se realizó un estudio de corte transversal que incluyó pacientes con LES desde abril hasta julio de 2018. Los pacientes completaron el LupusQoL y la escala Generalitat de Catalunya (GENCAT); se obtuvieron los datos sociodemográficos, índices de actividad (SLEDAI) y daño acumulado (SLICC). Se evaluó la fiabilidad mediante consistencia interna y se determinó la validez convergente del LupusQoL con la escala GENCAT. De los 100 pacientes, el 93% eran mujeres, la media de edad fue de 42 años (DE: 13) y la media de duración de la enfermedad fue de 11 años (DE: 9); la media de SLEDAI y SLICC fue de 3 y 1, respectivamente. El punto de corte que definió una «mejor» o «peor» CVRS para el LupusQoL fue 64,55 puntos. Se encontró una convergencia moderada posterior a la agrupación, según los puntos de corte, del LupusQoL con la escala GENCAT (coeficiente kappa de Cohen = 0,556; p = 0,000). El LupusQoL es válido como instrumento psicométricamente estable para medir la CVRS de los pacientes con LES en Venezuela. Se establecieron los puntos de corte que permiten estratificar la CVRS de los pacientes venezolanos con LES, siendo de utilidad para complementar una evaluación integral. Traditionally, the health-related quality of life (HRQoL) of patients with systemic lupus erythematosus (SLE) has been assessed using instruments that neglect the specific characteristics of the disease. This study determines the validity of the Lupus Quality of Life (LupusQoL) questionnaire as a psychometrically stable instrument to measure the HRQoL of patients with SLE in Venezuela and establishes the cutoff points of the questionnaire for the Venezuelan population. A cross-sectional study was conducted that included patients with SLE from April to July 2018. Patients completed the LupusQoL and the Generalitat de Catalunya (GENCAT) scale; sociodemographic data, activity index (SLEDAI) and accumulated damage (SLICC), were obtained. Reliability was evaluated by internal consistency and the convergent validity of the LupusQoL was determined with the GENCAT scale. Of the 100 patients, 93% were women, the mean age was 42 years old (SD: 13) and the mean duration of the disease was 11 years (SD: 9); the mean of SLEDAI and SLICC was 3 and 1, respectively. The cutoff point that defined a "better" or "worse" HRQoL for LupusQoL was 64.55 points. A moderate convergence was found after grouping, according to the cutoff points, of the LupusQoL with the GENCAT scale (Cohen's kappa coefficient =.556; p =.000). The LupusQoL is a valid psychometrically stable instrument to measure the HRQoL of patients with SLE in Venezuela. Cutoff points were established to stratify the HRQoL in the Venezuelan population with LES, being useful to complement a comprehensive evaluation. [ABSTRACT FROM AUTHOR]

Do politicians target the benefits of social programs to party loyalists or to swing voters? Traditional tests of this question are clouded by an identification problem caused by the simultaneity of politician and voter choices to participate in the exchange of assistance for votes. I use the holding of an unanticipated repeat gubernatorial election in the Venezuelan state of Barinas in 2022 as a natural experiment to identify the effects of elections on the distribution of government assistance. I estimate that the holding of the election led to an increase in the probability of voters in Barinas receiving food packages in comparison with the control group of voters in the state of Apure. I also find that moderate opposition and third-party voters received larger increases in food benefits. These results are consistent with the predictions of the spatial model of distributive politics, according to which elections lead governments to direct more benefits to swing voters instead of core supporters. The findings illustrate why investigation of cross sectional correlations is insufficient to test the implications of theories of voting if it is not accompanied by a clear identification strategy to help isolate the source of the underlying shocks. • I use an unanticipated repeat vote in Venezuela as a natural political experiment. • The election led to an increase in the probability of voters receiving food packages. • Third-party voters received more benefits, consistent with spatial models. • Traditional tests using cross sectional correlations lack an identification strategy. • This is the first time a repeat election is used to test theories of politics. [ABSTRACT FROM AUTHOR]

• Small and medium enterprises (SMEs) can be uniquely vulnerable to exogenous shocks and urban violence. • Survey evidence from Honduras, El Salvador and Venezuela reveals that smaller and informal businesses suffered most during COVID-19 and that increased violence and extortion was detrimental. • Receiving government support and engaging more with both the State and criminal groups was associated with better business outcomes for SMEs, as was engaging in charity and philanthropy in communities of operation. • While SMEs can be vulnerable to shocks and crises in complex institutional settings, they can also instrumentalize relationships, particularly with communities, in ways that may support resilience. Small and medium enterprises (SMEs) can be uniquely vulnerable to exogenous shocks and crises. In many Latin American cities, SMEs also face endemic challenges related to urban violence that can inhibit their operations and survival. Drawing on theory related to how small business vulnerability and resilience is shaped by firm capacity, dynamics of violence and businesses' networks and relationships, this article examines SMEs self-reported business outcomes in fragile urban contexts. We do so by utilising a novel primary survey of urban SME owners in Venezuela, El Salvador and Honduras conducted during the COVID-19 pandemic. Our results highlight how firms that were smaller, informal and faced increasing violence and extortion tended to suffer; while those that increased engagement with both the State and non-state criminal actors and those who supported their communities tended to fare better. While SMEs may face distinct liabilities in complex institutional settings, our findings suggest they can also exercise some agency in navigating urban violence and exogenous shocks by utilising both formal and informal support networks and fostering community linkages as resilience strategies. [ABSTRACT FROM AUTHOR]

Three-quarters of the global migrant population have fled fragile contexts, with 64 percent hosted by similarly vulnerable countries. These contexts account for about 75 percent of those living in extreme poverty. Despite the scale of this phenomenon, the extent to which the self-selection of South–South migrants differs from those migrating to more developed countries remains poorly understood. In this paper, I investigate the self-selection of Venezuelan migrants during the 2015–2021 crisis, which led to greater migration to less developed countries such as Colombia and Peru, compared to more developed ones like the United States and Chile. Using individual-level data representative of the Venezuelan population and similar data on Venezuelan migrants in these key destination countries, the study finds that migrants are generally positively selected in terms of education compared to those who remain in Venezuela, with migrants to developed countries being positively sorted with respect to those to developing countries. However, comparing the cumulative distribution functions of pre-migration predicted earnings reveals that migrants to developing countries are negatively selected relative to stayers, while migrants to developed countries are positively selected. This highlights the significant role of unobserved abilities in shaping South–South migration patterns. Furthermore, a discrete choice model shows that women and college graduates face lower migration costs, independent of expected earnings at the destination. Factors such as the distance to the destination country and pre-crisis networks also play a crucial role in shaping migration decisions. • Venezuelan migrants (2015-2021) are generally more educated than those who stayed. • Women and graduates migrated more, regardless of expected earnings at destinations. • Distance and networks lead Venezuelans to prefer neighboring developing countries. • South–South migrants have lower pre-migration earnings compared to those who stayed. • Migrants to developed countries have higher pre-migration earnings than stayers. [ABSTRACT FROM AUTHOR]

Despite its important position close to the Isthmus of Panama, and abundance of fossil localities, the palaeoenvironment of the Falcón Basin in northwestern Venezuela has been understudied. The basin includes a sequence containing 6 terrestrial fossil assemblages, of which 5 are well-sampled enough for palaeoenvironmental reconstruction. Here we use these assemblages as a test case for taxon-free approaches in the Neotropics, that have been used in studies elsewhere, including dental functional traits, body mass and mesowear. Mesowear reveals browsing and grazing diets from the Late Miocene to the Late Pleistocene, and though the toxodontids (the most abundant mammalian herbivores) show a consistent browsing signal, other approaches support an environment which was largely more open than previously suggested. We find limited evidence for any dramatic climatic shift, instead finding more gradual changes in precipitation and tree cover. Ultimately, we find enough consistency in our results with those of other proxies to suggest that the methods employed here could potentially be applied to other localities in South America. [Display omitted] • Dental and body mass ecometrics are applied to the mammals of Falcón, Venezuela. • Reconstructions are drier and more open than expected from other proxies. • Limited evidence for any sudden change in vegetation from ecometrics. • Mesowear angles in toxodontids suggest a consistent browsing signal. • Herbivore ecometric methods have potential elsewhere in South America. [ABSTRACT FROM AUTHOR]

• The introduction of visa restrictions across South America is unlikely to have deterred Venezuelan migration but instead it increased the likelihood of irregular entry of migrants. • These same restrictions increased the likelihood of migrants not having a regular permit once in the host country. • There is no evidence that using specific irregular routes increased the violence suffered reported by migrants. However, over a quarter of all migrants report having suffered some form of violence both before and after the introduction of restrictions. • The introduction of visa restrictions and consequent situation of migratory irregularity shifted migrants' priorities, mainly away from seeking employment, likely delaying their integration. • Within contexts of massive displacement and porous borders, introducing visa restrictions is likely ineffective and leads to negative externalities. Most countries across the globe introduce visa restrictions to regulate immigration, yet little is known about their effect on migrants' decision to migrate and their well-being. I study the mass displacement of Venezuelan nationals, and through a difference-in-differences research design, I compare the effectiveness of introducing visa restrictions in reducing overall migration flows in certain countries across South America. I use a data set of 85,000 migrants and refugees − mostly Venezuelans − surveyed by the UNHCR. Findings suggest that visa restrictions increased the likelihood of irregular entry and irregular visa status for migrants while also leading to changes in their priorities. Unexpectedly, I do not find evidence of increased violence suffered by migrants who switch towards irregular entry channels in specific countries. This research contributes to the academic and policy debate on the effectiveness of visa restrictions on migratory flows, as well the literature on the effects of migration policies on migrants' well-being. [ABSTRACT FROM AUTHOR]

This article explores how Venezuelan migrants in Peru negotiate sometimes-contradictory notions of identity, solidarity and modernity. Building from decolonial scholarship, it argues for the importance of situated racialized accounts of migrants' experiences. I found that a common identity as Latin Americans facilitated migration, with an emphasis on solidarity and 'brotherhood'. Yet, Venezuelans' narratives also reinforced hierarchical notions of development that position whiter populations as more advanced than indigenous populations. Their stories reveal a constant negotiation between discourses of shared identity and hierarchical understandings of development and modernity that are constantly perpetuated under the coloniality of power. My findings reiterate a need to not only consider multiple intersecting components of migrant identities but also the ways in which identities shift and take on different meanings in different spatial contexts. Based on 18 migrant narratives, the article addresses a lacuna of analyses examining how migrants themselves re-theorize race and development. By centering coloniality and racialization in migration, I challenge linear narratives of migration from less developed to more developed countries and show how some migrants grapple with vulnerability while also reinforcing uneven power dynamics of racialized othering. [ABSTRACT FROM AUTHOR]

An innovative ecofriendly high-performance thin layer chromatographic (HPTLC) method with spectrophotometric detection for simultaneous determination of Tramadol (TMD), Tapentadol (TAP), and Venlafaxine (VEN) in seized dosage forms was presented. Our method was conducted to achieve separation following the optimal conditions: pre-coated silica gel plates using a green mobile phase (heptane: acetone: ammonia, 7:3:0.5 v/v), with absorbance scanning at 272 nm. The validation of the method was done following International Conference on Harmonization (ICH) guidelines, demonstrates linearity, accuracy, precision, selectivity, robustness, and system suitability. Separation was achieved with a detection limit of 0.34, 0.16, and 0.084 (ug/band) for TMD, TAP, and VEN, respectively, the method successfully analyzes seized samples. Trueness is confirmed through a high degree of similarity between HPTLC and gas chromatography results. The study's ecofriendly approach, simplicity, and selectivity position it as a promising method for efficient, on-site monitoring of seized samples. [Display omitted] • Introduction of a novel densitometric HPTLC method for the precise separation and quantification of TMD, TAP, and VEN. • Implementation of an environmentally friendly mobile system to effectively separate these drugs in confiscated dosage forms. • Demonstrated superior selectivity and sensitivity of the method, particularly in separating structurally related drugs. • Potential value of the developed method in high throughput monitoring of abused drugs at the point of interception. [ABSTRACT FROM AUTHOR]

The recent increase in Venezuelan migrants and refugees to Brazil has prompted a humanitarian response coordinated by multiple government agencies and inter/national organisations. This coordination effort sits under the umbrella of the Operation Welcome task force, in which the military is heavily involved. Situated in the northern state of Roraima, bordering Venezuela, this article explores one particular site of humanitarian care: a set of Water, Sanitation and Hygiene (WASH) facilities located in the capital city of Boa Vista. Here, I investigate the militaristic design and processes of the shower block, which is available to Venezuelan refugees and migrants who are living without adequate shelter. In doing so, this paper argues that the normalisation of militarism in humanitarian intervention (re)produces exclusion and precarity for those accessing spaces of care. By understanding the water infrastructure of the site as an infrastructure of containment, this research shines light on the everyday, often invisiblised implications of migration governance that occur at the micro-scale. In particular, it highlights the conditions of slow and symbolic violence that are embedded within the military-humanitarian response. [ABSTRACT FROM AUTHOR]

The La Rinconada Terrane comprises the core of Margarita Island, Venezuela; it is a composite unit composed of rocks of both continental and oceanic affinity that were brought together and metamorphosed at high-pressure and low- to medium-temperature conditions in a collision zone along NW South America in Albian to Cenomanian time. Details of the ensuing three-stage exhumation path and concomitant eastward translation until Miocene oblique collision of Margarita with central and eastern Venezuela have remained the subject of discussion. In this paper we integrate the results of published age dating and the details of extensive Rb-Sr, K-Ar, 40Ar/39Ar and fission track dating that have been only superficially presented to date. Initial exhumation from high-pressure conditions into ductile mid-crustal levels occurred at 90-80 Ma, followed by essentially isobaric, isothermal conditions for ca. 30 Myr during which the La Rinconada Terrane was subjected to continual ductile penetrative shearing and recrystallization. Partial to total recrystallization with concomitant partial to total isotopic re-equilibration, especially of quartz-rich rocks, was widespread during this time interval. The youngest Rb-Sr, K-Ar and 40Ar/39Ar ages cluster at ca. 50 Ma. Zircon fission track ages of 50–40 Ma corroborate exhumation into brittle levels of the crust at this time. An apatite fission track age of 23 Ma indicates the attainment of shallow depths in Miocene time. This discontinuous history of exhumation fits tectonic models of the Caribbean well. As the Caribbean Plate led by the Antilles Arc entered the gap between the Americas, strongly dextral, transpressive subduction in the SE Caribbean drove shear deep within the forearc. The La Rinconada Terrane of Margarita was exhumed to mid-crustal depths in the Late Cretaceous and is suggested to have occupied high-angle forearc shear zones above the primary Benioff Plane. As the arc migrated past the Guajira promontory and became extensional due to roll-back of Proto-Caribbean oceanic crust north of the Falcón re-entrant of the South American margin, the La Rinconada Terrane formed the footwall of an Eocene lithospheric rift that opened by late Eocene into the Grenada (oceanic intra-arc) Basin, effecting exhumation into the brittle crust. The progressive obduction of the SE Caribbean Plate onto the South American continental margin during prolonged dextral oblique collision completed most of Margarita's exhumation history by middle Miocene time (17–12 Ma). [Display omitted] • High-pressure rocks of Margarita show a discontinuous 70 Myr exhumation path. • Rb-Sr, K-Ar, 40Ar/39Ar, zircon/apatite fission-track data allow sequential tracking. • A 20–30 Myr mid-crustal hiatus is marked by strong ductile penetrative shearing. • Shearing causes partial/total isotopic resetting/recrystallization of many rocks. • Exhumation path correlates well with Caribbean tectonic history. [ABSTRACT FROM AUTHOR]

This study examines the impact of integrating refugee children into host states' education systems and localizing humanitarian responses on the authority and responsibilities distributed among global and local actors. Focused on Venezuelan refugee education in Colombia, our multilevel analysis reveals sporadic horizontal dialogue and fair coordination only when local expertise serves the purposes of humanitarian organizations. These positive effects coexist with power imbalances and responsibility dilution, primarily affecting local actors. These disparities yield suboptimal interventions for refugee children. Mapping the global-local chains of authority and responsibility, the study elucidates the possibilities and limitations of current governance arrangements for refugee education. • Refugee integration and localizing aid alter global-local responsibility and authority. • International organizations concentrate authority unless locals aligned with their goals. • Integration creates blame games ultimately burdening schools and teachers. • Power imbalances and diluted responsibility lead to unsustainable, unresponsive strategies. [ABSTRACT FROM AUTHOR]

Comprehensive methodologies for monitoring microplastics (MPs) in the ocean are critical for accurately assessing abundances across a broad size spectrum, and to document distributions, sources, sinks, temporal trends, and exposure risks for organisms. Discrete 0.5-L water samples from the northeastern-coast of Venezuela (NECV), Pacific-Arctic Ocean (PAO), and Gulf Stream Current (GSC) were analyzed by Raman microspectroscopy to detect MPs not captured by net-tow surveys. Equivalent spherical diameters (ESD) of most MPs were <5 μm, accounting for 68, 83, 86 % of total inventories in NECV, GSC, PAO samples. We did not observe a single MP particle >53 μm ESD. Abundances of MPs in the 0.5–200 μm size fraction were 5–6 orders of magnitude higher than previous surveys that were almost exclusively based on net tow collections of MPs > 300 μm ESD. Abundances of MPs in NECV samples were ~10-fold higher than those from PAO and GSC. The most abundant polymers were polypropylene (PP), polystyrene (PS) and polyethylene terephthalate (PET), consistent with composition of plastic waste generated globally. • Most abundant microplastics were between 1 and 14 μm equivalent spherical diameters. • 60 % of microplastics were <5 μm and none were larger than 53 μm. • Microplastics <53 μm were 6 orders of magnitude higher than surveys based on net tow. • Microplastics were more abundant in Venezuelan waters relative to the other sites. • Specific polymer contributions match plastic waste composition reported in the ocean. [ABSTRACT FROM AUTHOR]

The literature has examined individual predictors of attitudes toward immigrants, controlled by supra-individual variables, especially in European and North American countries. Nevertheless, this analysis has not been made using South-south migration communities. Thus, this study analyzed the individual predictors of the attitudes toward immigrants from Perú and Venezuela in a Chilean sample, controlling supra-individual variables. We used available data (N total = 956, composed of 599 and 357 for Peruvians and Venezuelans, respectively), considering seven predictors and three types of intergroup attitudes. The main results indicated that contact quality, similarity and social dominance orientation were related to almost all types of attitudes (symbolic threat, realistic threat and liking) toward both immigrant populations, except that similarity and dominance orientation were not associated with realistic threats and liking toward Venezuelans, respectively. The rest of the predictors, contact quantity, generalized trust, political orientation, and right-wing authoritarianism explained three or fewer types of attitudes toward both immigrant communities. We speculated about the reasons why contact quality, similarity and social dominance orientation were associated with more types of attitudes than the rest of the predictors, and the present model's robustness. [ABSTRACT FROM AUTHOR]

This paper analyses the failure of the traditional Ricardo–Haberlerian (1817; 1936) theory of comparative advantage (RTCA) in a strategic market game à la Shapley–Shubik (1977). In this model, trade is driven, not by comparative advantages, but by strategic considerations. We prove, in a Ricardian framework, the simultaneous existence of two types of equilibria, at both of which active international trade takes place. In the first type of equilibrium, both countries specialise based on comparative advantages. In the other, each country produces only its comparative-disadvantage good. The welfare properties, and policy implications of this result (using the examples of the China–US trade war and Venezuela), are discussed at length in two dedicated sections. We show that the predictions of the RTCA depend, not on the number of agents in the economy, but on the nature of agents: the RTCA fails to obtain even with an infinite number of large players in each country. We prove that the RTCA prevails when agents are price-takers, and establish the conditions under which equilibria of our market game coincide with Walrasian ones. [ABSTRACT FROM AUTHOR]

This study examines the multiscale spillovers and nonlinear causalities between the crude oil futures market and the stock markets of the United States (US), Canada, China, Russia, and Venezuela before and during the COVID-19 pandemic. Using the wavelet coherency method, we find strong co-movement between the oil futures market and these five stock markets, particularly from March 2020 to May 2020 (initial period of the COVID-19 outbreak) at high frequency. Furthermore, we find positive co-movements at low frequency during the overall COVID-19 period. This finding suggests that the bearish trend of stock markets is associated with a downward movement in oil prices. Using the wavelet-based Granger causality approach, we find that the oil and stock indices have less co-movement on a smaller scale but greater movement on a larger scale across all periods. As an exception, the Russian market is significantly influenced by oil prices, even on a small scale, before the COVID-19 period, but not after the beginning of the pandemic. We also find effects in the opposite direction—the Canadian and U.S. markets influence oil prices on a small scale during the COVID-19 period, an effect that is not visible for the U.S. market in the pre-COVID-19 sample. The results also show a significant bidirectional causality from oil to stock markets and vice versa during Russian-Saudi oil price war at high scale. Furthermore, we find that investors should hold more oil futures than stock shares in their portfolios for all periods. This evidence confirms that oil instruments are important for hedging during normal periods and act as safe-haven assets during crisis periods. We observe that the U.S. and Canadian stock markets were more affected by oil price shocks than were other countries. [ABSTRACT FROM AUTHOR]

This study assessed the prevalence of radix entomolaris and 2 canals at the distal aspect of mandibular first molars among different geographic regions by means of cone-beam computed tomographic imaging. Precalibrated observers from 23 worldwide geographic locations followed a standardized screening protocol to assess 5750 cone-beam computed tomographic images of mandibular first molars (250 per region), gathering demographic data and recording the presence of radix entomolaris and a second canal at the distal aspect of teeth. Intra- and interrater reliability tests were conducted and comparisons among groups were performed using proportions and odds ratio forest plots. The significance level was set at 5%. The results of intra- and interrater tests were above 0.79. The prevalence of radix entomolaris varied from 0.9% in Venezuela (95% confidence interval [CI], 0%–1.9%) to 22.4% in China (95% CI, 17.2%–27.6%). Regarding the proportion of a second distal canal, it ranged from 16.4% in Venezuela (95% CI, 11.8%–21.0%) to 60.0% in Egypt (95% CI, 53.9%–66.1%). The East Asia subgroup was associated with a significantly higher prevalence of an extra distolingual root, whereas the American subgroup, the American native ethnic group, and elderly patients were linked to significantly lower percentages of a second canal at the distal aspect of teeth. No significant differences were noted between male or female patients. The overall worldwide prevalence rates of radix entomolaris and a second canal at the distal aspect of the mandibular first molar were 5.6% and 36.9%, respectively. The East Asia geographic region and Asian ethnic group had a higher prevalence of a second distal root. [ABSTRACT FROM AUTHOR]

Hydropower compounds most of the energy matrix of the countries of the Latin America and Caribbean region (LAC). Considering the concern in reducing Green House Gases emissions (GHG) from hydropower plants and hydrogen production from fossil sources, green hydrogen (H 2) appears as an energy vector able to mitigate this impact. Improving the efficiency of the plant and producing renewable energy the element is an interesting alternative from the ecological and economic point of view. This study aims to estimate the potential of H 2 production from wasted energy, through the electrolysis of water in hydroelectric plants in Colombia and Venezuela. The construction of two scenarios allowed obtaining a difference, considering a spilled flow of 2/3 in the first scenario and 1/3 in the second. In Colombia, hydrogen production reached 3.39 E+08 Nm3 at a cost of 2.05 E+05 USD/kWh in scenario1, and 1.70 E+08 Nm3 costing 4.10 E+05 USD/kWh in scenario 2. Regarding the Venezuelan context, the country obtained lower production values of H 2 , ranging between 7.76 E+07 Nm3.d−1 and 4.31 E+07 Nm3.d−1, and production cost between 9.45 E+09 USD/kWh and 1.89 E+10 USD/kWh. Thus, the final cost for the production and storage of H 2 was estimated at 0.2239 USD.kg−1. Ultimately, Colombia and Venezuela have a large potential to supply the demand for nitrogen fertilizers with green ammonia production, apply green hydrogen in manufacturing and use the surplus for energy substitution of Liquefied Petroleum Gas - LPG. In Colombia, the chemical energy offered is equivalent to 6.681 E+11 MJ/year−1 and in Venezuela, the result is equal to 1.697 E+11 MJ/year−1 in the conservative scenario. Finally, the countries have great potential for the diversification of the energy matrix and the insertion of renewables in the system. [Display omitted] • Venezuelan and Colombian potential for green hydrogen production. • Venezuela produces 7.76 E+07 Nm3.d−1 to 4.31 E+07 Nm3.d−1 of H 2. • Colombia has a daily H 2 production equal to 3.39 E+08 Nm3. [ABSTRACT FROM AUTHOR]

This paper re-examines the dependence structure between uncertainty in oil prices and sovereign credit risk of oil exporters. To address this issue, we employ a copula approach that allows us to capture asymmetric and nonlinear dependence structures. Empirical analyses involve daily data of the 5-year sovereign credit default swaps spreads and the crude oil implied volatility from January 2010 to May 2019, covering a sample of ten oil-exporting countries. Except for Brazil and Venezuela, our results provide evidence of significant positive and upper tail dependence in the relationship between oil market uncertainty and oil exporters' sovereign risk. Overall, our findings highlight that high uncertainty in oil prices coincides with large-scale increases in the sovereign credit risk of oil-exporting countries, supporting the hypothesis that investors, exposed to economic losses from risk events in oil exporters, are all the more pessimistic that prevails high uncertainty about future oil prices. Our findings have implications for oil exporter' policymakers as well as investors. • We study the relationship between oil price volatility and the sovereign risk of oil exporters. • We use daily data of the sovereign CDS spreads and the crude oil implied volatility. • We provide evidence of positive and upper tail dependence in the relationship. • High uncertainty in oil prices coincides with a surge in the sovereign CDS spreads of oil exporters. [ABSTRACT FROM AUTHOR]

Due to complex social, political and economic causes, Venezuela has encountered difficulties managing the Covid-19 pandemic. Although a vaccination program has started, it is still comparatively slow and largely inefficient. One particular challenge has been vaccine hesitancy. Venezuelan policymakers have traditionally not rendered much attention to ethnic disparities. In this study, we assess whether vaccine hesitancy varies across ethnic groups, in a sample of 273 Venezuelan university students. Results come out showing that marginalized ethnic groups in Venezuela are more prone to vaccine hesitancy, and also have greater levels of acceptance regarding conspiracy theories. Coefficients of correlation of ethnic discrimination with vaccine hesitancy and conspiracy beliefs are moderate. Coefficients of correlation of paranoid ideation with vaccine hesitancy and conspiracy beliefs are weak. This suggests that in order to successfully complete the vaccination program, policymakers in Venezuela must begin to approach racial disparities. [ABSTRACT FROM AUTHOR]

• A longitudinal study to determine the immoglobulin G response after Sputnik V vaccine • SARS-CoV-2 seronegative vaccinees showed a primary response upon vaccination • Seropositive individuals displayed a booster or secondary immune response • This immoglobulin G response was stronger than 2 vaccine doses in the seronegatives • A single vaccine dose did not always protect; we registered breakthrough infections Introduction: We evaluated the immunoglobulin (Ig) G antibody response against the nucleocapsid protein (NP) and the receptor-binding domain (RBD) of the spike protein of SARS-CoV-2 in a cohort of 86 individuals in Venezuela, before and after receiving the Sputnik V vaccine. Methods: Antibody responses against NP and RBD were determined with an enzyme-linked immunosorbent assay just before, 3 weeks after the first, and 6 weeks after the second dose of the vaccine. Results: Before vaccination, 59 individuals were seronegative, and 27 seropositive for NP and/or RBD. Of the seronegative cohort, 42% did not develop an IgG immune response against RBD after the first vaccine dose, but 100% had a strong IgG response after 2 doses. All seropositive individuals developed a strong IgG antibody response against RBD after the first vaccine dose, with antibody levels ∼40% higher than seronegative individuals who had received 2 doses. Previously seropositive subjects showed no significant increase in IgG antibody response against RBD after the second vaccine dose. Conclusions: We demonstrate that 2 doses of the Sputnik V vaccine triggered antibody response in all study individuals. The second Sputnik V dose had no impact on IgG response for those seropositive for SARS-CoV-2 antigens before vaccination. [ABSTRACT FROM AUTHOR]

• Having a common market in latin america might be feasible. • Despite venezuela and Nicaragua, the rest of the countries show signs of convergence. • An economic convergence index is built based on the maastricht criteria. • Convergence is significant during the last decade. This paper aims to analyze economic and commercial convergence in the three active integration agreements in the region: Central American Integration System, Southern Common Market, and Pacific Alliance. To this end, we estimated the Economic Convergence Index and correlations among the main macroeconomic aggregates. The empirical evidence reveals that, apart from Venezuela, Latin American countries have a high potential to form a common market. This potential derives more from the dynamics of their economies than from the political blocs or agreements that States want to pursue. [ABSTRACT FROM AUTHOR]

Asphalt binders harden over time through both thermo-reversible and irreversible processes which, in turn, promote cracking and moisture damage in service. Oil exudation plays a significant role in accelerating both pavement distresses. Given the increasing use of oils to facilitate polymer modification and soften or rejuvenate reclaimed asphalt, a test for exudation is key to safeguarding binder quality and durability. The objective of this study was to develop a simplified, quantitative, precise and accurate test protocol. Samples from 14 northeastern Ontario pavement trial sections together with eight straight Alberta and Venezuelan binders with known superior performance were aged in a pressure aging vessel. Samples were ultrasonicated for 20 min in ethanol to accelerate exudation and tested using a dynamic shear rheometer. The ethanol was analyzed using gas chromatography-mass spectrometry to chemically identify exuded constituents. Results show that all modified binders were significantly more affected by exudation of long chain saturates compared to straight Alberta and Venezuelan binders. High amounts of polymer modifiers, such as styrene-butadiene and reactive ethylene terpolymer, as often promoted in modern-day formulations, accelerated the exudation process likely due to their destabilizing effects on colloidal binder structures. Exudation phenomena help explain the reduced lifespans for most of the modified binders in the two pavement trials. • Straight asphalt binders from Alberta and Venezuela show little to no oil exudation. • Highly modified binders appear to suffer significantly from exudative hardening. • Oil exudation likely causes premature cracking and moisture damage in pavements. [ABSTRACT FROM AUTHOR]

[Display omitted] • There is a high level of nucleotide diversity across the Pfama -1 gene circulating in Cameroon. • Pfama -1 Domain I is the most diverse and could contribute to host immune escape. • Pfama -1 genetic diversity is driven and maintained by positive natural selection. • Comparable immune pressure and selective forces operate across malaria endemic regions. Antigenic variation associated with genetic diversity in global Plasmodium falciparum apical membrane antigen-1 (PfAMA-1) is a major impediment to designing an effective malaria vaccine. Here, we report the first study on genetic diversity and natural selection of the Pfama -1 gene in P. falciparum isolates from Cameroon. A total of 328 P. falciparum positive samples collected during 2016 and 2019 from five localities of Cameroon were analysed. The ectodomain coding fragment of Pfama -1 gene was amplified for polymorphism profiling and natural selection analysis. A total of 108 distinct haplotypes were found in 203 P. falciparum isolates with considerable nucleotide diversity (π = 0.016) and haplotype diversity (Hd = 0.976). Most amino acid substitutions detected were scattered in ectodomain-I and few specific mutations viz P145L, K148Q, K462I, L463F, N471K, S482L, E537G, K546R and I547F were seen only in Cameroonian isolates. A tendency of natural selection towards positive diversifying selection was observed (Taj-D = 2.058). Five positively selected codon sites (P145L, S283L, Q308E/K, P330S and I547F) were identified, which overlapped with predicted B-cell epitopes and red blood cell (RBC) binding sites, suggesting their potential implication in host immune pressure and parasite-RBC binding complex modulation. The Cameroonian P. falciparum populations indicated a moderate level of genetic differentiation when compared with global sequences, with few exceptions from Vietnam and Venezuela. Our findings provide baseline data on existing Pfama -1 gene polymorphisms in Cameroonian field isolates, which will be useful information for malaria vaccine design. [ABSTRACT FROM AUTHOR]

• We examine the multidimensional character of migration policy preferences, and whether humanitarian values matter for these preferences. • We conducted a pre-registered conjoint experiment in Colombia in 2021 (N = 2,508), a major host of forced migrants globally. • Colombians favor fewer restrictions on Venezuelans' right to work, healthcare access, family reunification, or location within Colombia. • There is support for placing some restrictions on the number of Venezuelans entering the country and the length of their residence in Colombia. • Respondents holding stronger humanitarian preferences favor fewer restrictions in domains addressing core needs of health, family, and work. What migration policies do people in receiving countries prefer, and to what extent do humanitarian concerns matter for these preferences? Despite sustained scholarly attention to migration attitudes in high-income countries, much less work examines public policy preferences—particularly in low- and middle-income countries that receive most forced migrants globally. While legislators can propose and implement migration policies involving multiple domains that differ in restrictiveness, their choices partly rely on public support that may vary depending on the policy area at stake. This makes understanding preferences for realistic migration policies in a multidimensional manner theoretically and empirically important. In response, we conducted a pre-registered conjoint experiment (N = 2,508) fielded in Colombia, the country that has received the largest share of Venezuelan emigrants who themselves currently comprise one of the world's largest migratory flows. Colombians prefer more open policy options that place either some or no restrictions on Venezuelan migrants' labor market access, ability to bring family members, access to public healthcare, or freedom to choose where they live within Colombia. However, there is support for restrictions on the overall number of Venezuelans allowed to settle in the country, as well as the length of time that Venezuelans are allowed to stay in Colombia. Moreover, respondents holding higher levels of humanitarianism prefer less restrictive policies towards Venezuelans relative to those holding stronger economic and material values—particularly in domains addressing core needs of health, family reunification, and employment. Our study contributes novel and timely evidence of multidimensional migration policy preferences from a highly-impacted case, while also showing how altruistic values relating to humanitarianism selectively matter for these preferences. [ABSTRACT FROM AUTHOR]

Venezuela is currently experiencing the biggest crisis in its recent history. This has led more than 7.3 million Venezuelans to emigrate, at least 1.5 million of those to Peru, which amounted to an increase of over 4 percent in the Peruvian population. Venezuelan immigrants in Peru are relatively similar in cultural terms, but, on average, more skilled than Peruvians. In this paper, we first examine Venezuelans' perceptions of being discriminated against in Peru. Using an instrumental variable strategy, we document a causal relationship between the level of employment in the informal sector – where most immigrants are employed – and reports of discrimination. We then study the impact of Venezuelan migration on local's labor market outcomes, reported crime rates, and attitudes using a variety of data sources. We find that inflows of Venezuelans to particular locations led to increased employment and income among locals, decreased reported crime, and improved reported community quality. We conduct a heterogeneity analysis to identify the mechanisms behind these labor market effects and discuss the implications for Peruvian immigration policy. • We analyze the impact of Venezuelan immigration on the Peruvian labor market • We also study the labor market determinants of discrimination against Venezuelans. • Immigration has mostly positive effects on natives' labor market outcomes. • More informal labor market competition increases discrimination against immigrants. • We discuss the implications for Peruvian immigration policy. [ABSTRACT FROM AUTHOR]

Adaptar transculturalmente y validar la metodología COPCORD en población indígena Wayuu del estado Zulia, Venezuela. Se realizó un estudio de corte transversal en indígenas Wayuu de los municipios Mara y Guajira del estado Zulia, Venezuela, se adaptó transculturalmente la versión venezolana del cuestionario COPCORD y se tradujo del español venezolano al wayuunaiki (idioma Wayuu). Cien indígenas Wayuu aceptaron participar y se les administró el instrumento, casa por casa, por personal de salud bilingüe capacitado. Los individuos COPCORD positivos fueron evaluados por reumatólogos. Se realizó análisis descriptivo de variables, se midieron alfa de Cronbach, correlación de Spearman, análisis de prueba de cribado (sensibilidad, especificidad, VPP y RVs+). El 66% fueron mujeres, edad promedio 41,4 años, el 20% monolingües, el 21% analfabetos, el 69% unidos/casados, el 57% con trabajo informal. El 62% reportaron dolor, el 56% con criterios de enfermedades reumáticas; las más frecuentes fueron: osteoartritis (32,3%), lumbalgia mecánica (13,9%) y síndrome doloroso regional reumático (12,3%). Cinco dimensiones del instrumento presentaron alfa de Cronbach > 0,7. La sensibilidad fue del 100% y la especificidad del 11,1%, VPP 14,3%, RVs+ 1,13%. El COPCORD es válido y útil como herramienta de cribado para la detección de malestares musculoesqueléticos y enfermedades reumáticas en la población indígena Wayuu. To adapt cross-culturally and validate the COPCORD methodology in the indigenous Wayuu population of Zulia state, Venezuela. A cross-sectional study was conducted on Wayuu indigenous people from the Mara and Guajira municipalities of the state of Zulia, Venezuela. The Venezuelan version of the COPCORD questionnaire was transculturally adapted and translated from Venezuelan Spanish to Wayuunaiki (Wayuu language). One hundred indigenous Wayuu, agreed to participate, they were administered the instrument, house by house, by health personnel, who were bilingual and previously trained. Positive COPCORD individuals were evaluated by rheumatologists. A descriptive analysis of variables was performed, Cronbach's alpha was measured, Spearman's correlation, screening test analysis (sensitivity, specificity, VPP and SVR+). 66% were women, average age 41.4 years, 20% monolingual, 21% illiterate, 69% in a couple/married, 57% with informal work. Sixty-two percent reported pain, 56% with criteria of rheumatic diseases, the most frequent were: osteoarthritis (32.3%), mechanical lower back pain (13.9%), and regional rheumatic pain syndrome (12.3%). Five dimensions of the instrument presented Cronbach's alpha > 0.7. The sensitivity was 100% and specificity 11.1%, VPP 14.3%, SVR+ 1.13%. The COPCORD is valid and useful as a screening tool for the detection of musculoskeletal complaints and rheumatic diseases in the indigenous Wayuu population. [ABSTRACT FROM AUTHOR]

Background: No previous study in Venezuela and few in the Region of the Americas have reported national cardiometabolic health data.Objectives: To determine the prevalence and distribution of cardiometabolic risk factors (CMRF) in adults of Venezuela.Methods: A population-based, cross-sectional, and randomized cluster sampling national study was designed to recruit 4454 adults with 20 years or older from the eight regions of the country from July 2014 to January 2017. Sociodemographic, clinical, physical activity, nutritional, and psychological questionnaires; anthropometrics, blood pressure, and biochemical measurements were obtained. The results were weighted by gender, age, and regions.Results: Data from 3414 participants (77% of recruited), 52.2% female, mean age of 41.2 ± 15.8 years, were analyzed. CMRF adjusted-prevalence were: diabetes (12.3%), prediabetes (34.9%), hypertension (34.1%), obesity (24.6%), overweight (34.4%), abdominal obesity (47.6%), underweight (4.4%), hypercholesterolemia (19.8%), hypertriglyceridemia (22.7%), low HDL-cholesterol (63.2%), high LDL-c (20.5%), daily consumption of fruits (20.9%) and vegetables (30.0%), insufficient physical activity (35.2%), anxiety (14.6%) and depression (3.2%) symptoms, current smoker (11.7%), and high (≥ 20%) 10-year fatal cardiovascular risk (14.0%). CMRF prevalence varied according to gender, age and region of residence.Conclusions: Cardiometabolic risk factors are highly prevalent in Venezuelan adults. This situation can be affected by the severe socio-economic crisis in the country. The joint action of different stakeholders to implement public health strategies for the prevention and treatment of these risk factors in Venezuela is urgently needed. [ABSTRACT FROM AUTHOR]

• Alkaloid profile of 5 species from Amaryllidaceae family collected from Venezuela. • Lycorine and related compounds were present in almost all samples analyzed. • Alkaloid extracts showed high to moderate inhibitory effect on AChE and BuChE. • Crinum amabile leaves extract show the strongest activity on AChE at 0.88 μg/mL. • BuChE enzyme was inhibited by crinum amabile leaves extract at 4.46 μg/mL. • Buphanisine theoretical inhibitory activity against cholinesterase enzymes. The Amaryllidaceae family is distributed mainly in tropical and subtropical areas but also in temperate zones. In Venezuela, there are 6 genera and 13 species distributed around the country. This family is characterized by its ability to biosynthesize alkaloids with an isoquinoline type structure. In addition, a number of investigations have revealed a variety of biological activities for these alkaloids, such as antimalarial, antitumoral, analgesic, antimicrobial, cytotoxic, acetylcholinesterase inhibitory activity, among others. Galanthamine, an alkaloid first obtained from Galanthus woronowii , has been used since 2001 for the palliative therapy of mild-moderate Alzheimer's disease. Therefore, there is great interest on searching for galanthamine sources among the wide range of Amaryllidaceae species distributed around the world. The present investigation, carried out with five species from the Amaryllidaceae family, Crinum amabile, Crinum erubescens, Crinum moorei, Amaryllis belladonna and Zephyranthes carinata , collected from different locations in Mérida State-Venezuela and analyzed by GC–MS, showed the alkaloid profile of leaves and bulbs of these species. Results revealed that lycorine and related compounds, such as 11,12-dehydro-anhydrolycorine and 1- O -acetyllycorine, were present in almost all samples analyzed, with lycorine predominant. The acetylcholinesterase (AChE) and butyrylcholinesterase (BuChE) inhibition capacity of these alkaloid extracts showed a strong to moderate inhibitory effect on both enzymes; C. amabile leaves being the extract with the strongest inhibitory activity against AChE at 0.88 µg/mL as well as BuChE at 4.46 µg/mL, followed by Crinum erubescens leaves with values of 1.75 µg/mL and 8.72 µg/mL, respectively, compared to the values observed for galanthamine used as control. Present investigation constitutes the first in silico report about buphanisine interactions with AChE and BuChE active sites. [ABSTRACT FROM AUTHOR]

Tulio Briceño-Maaz, MD, was a multifaceted man. During his long life, he developed very many activities in several fields of medicine, including dermatology and mycology. All were signaled by quiet work, firm objectives, and measurable achievements. They showed tenacity, genteelness, and lasting positive results. His life span coincided with the sinusoidal transition of Venezuela from a rural background country, plagued by armed and civil unrest, to a nation ready to position herself in the ranks of countries achieving development. By the time of Dr Briceño-Maaz's death, unfortunately, Venezuela involuted into a process of degeneration and autophagy still present today. [ABSTRACT FROM AUTHOR]

In the second half of the 20th century, an important series of scientific and sociopolitical events took place in Venezuela. These developments were related to changes in the world and particularly in the United States. In dermatology, beneficial and marked advances germinated and grew. They were propelled in Venezuela by particular characteristics in the local development of this specialty and critically by personal features of two major leaders, Dr Francisco Kerdel-Vegas, who died June 18, 2020, at the age of 92, and Dr Jacinto Convit, who died in 2014 at the age of 101. The interaction of these two cooperating leaders and the scientific and social environment with which they acted are presented. [ABSTRACT FROM AUTHOR]

To identify clusters of patients with major depressive disorder (MDD) based on the baseline 17-item Hamilton Rating Scale for Depression (HAM-D 17) items and to evaluate the efficacy of venlafaxine extended release (VEN) vs placebo, and the potential effect of dose on efficacy, in each cluster. Cluster analysis was performed to identify clusters based on standardized HAM-D 17 item scores of individual patient data at baseline from 9 double-blind, placebo-controlled studies of VEN for MDD. Change from baseline in HAM-D 17 total score was analyzed using a mixed-effects model for repeated measures for each cluster; response and remission rates at week 8 were analyzed using logistic regression. Discontinuation rates were also evaluated in each cluster. In 2599 patients, 3 patient clusters were identified, characterized as High modified Core (mCore) Symptoms/High Anxiety (cluster 1), High mCore Symptoms/Medium Anxiety (cluster 2), and Medium mCore Symptoms/Medium Anxiety (cluster 3). Significant effects of VEN vs placebo were observed on change from baseline in HAM-D 17 total score at week 8 for both clusters 1 and 2 (both P < 0.001), but not for cluster 3. In cluster 3, a significant treatment effect of VEN was observed at week 8 in the lower-dose subgroup but not in the higher-dose subgroup. All-cause discontinuation rates were significantly higher in placebo than VEN in each cluster. Three unique clusters of patients were identified differing in baseline mCore symptoms and anxiety. Cluster membership may predict efficacy outcomes and contribute to dose effects in patients treated with VEN. NCT01441440; other studies included in this analysis were conducted before the requirement to register clinical studies took effect. • Three clusters were identified for MDD, characterized as the severity of modified core-depressive symptoms and anxiety. • Treatment effects of venlafaxine differed across patient clusters. • Baseline symptom clusters for MDD are useful in predicting dose-dependent treatment effect of venlafaxine extended release. • Further exploration of factors that may affect efficacy of venlafaxine is needed. [ABSTRACT FROM AUTHOR]

There are currently nearly 1 billion migrants, of whom 259 million are international migrants, according to the World Health Organization. In the Americas, Venezuela has the highest migratory flow in the region in recent history. By September 2019, more than 4,300,000 people of all social classes had left the country. They included more than 24,000 doctors, who were fleeing the serious political, economic, and social crises affecting that nation. Others in the exodus are a large number of university faculty. The author's personal experience as a migrant doctor is presented, and job alternatives beyond medical practice/clinical medicine are described. The exodus of highly qualified personnel is not a new phenomenon but one that negatively affects the region or country of origin, whereas the receiving place benefits from the professionals who manage to join the workforce in their field of training. This, of course, is dependent on their complying with requirements to obtain legal residency and respective licensures, in addition to finding existing alternatives according to their expertise. To achieve this objective, they require a network of relatives, colleagues, and friends who can provide guidance on the steps to be followed; being fluent in the language of the new residence; and obtaining the necessary certifications to practice the profession either by taking the legally required examinations or by obtaining another degree from a university in the country. [ABSTRACT FROM AUTHOR]

José Maria Vargas, (1786-1854), who was born on March 10, 1796, graduated with a Doctor of Medicine degree from the Central University of Venezuela in 1808. He was subsequently imprisoned in 1813 by the Spanish authorities for his independence activities. When finally freed, he traveled to Edinburgh for postgraduate medical training and became the first Venezuelan to earn a Fellowship of the Royal Colleges of Surgeons of Edinburgh. He worked afterward in medicine, surgery, botany, and chemistry, practicing in Scotland, France, and Puerto Rico. Upon his return to Venezuela in 1825 from 1827 to 1829, he became Professor of Surgery and later, President (Rector) of the Central University of Venezuela. He was elected the second president of newly independent Venezuela serving from 1835 to 1836 and carried out his tasks with honor and dignity, even after surviving a coup d'état. Finally, he resigned his position as president and returned to the practice of medicine and his teaching duties. He reasoned and wrote a beautiful differential diagnosis in a case supposedly of pellagra, but actually of erythema marginatum. Dr Vargas died in New York on July 13, 1854, after a long illness. [ABSTRACT FROM AUTHOR]

• Human Bocavirus infects children of <5 months of age from the Amazon Region with acute gastroenteritis and respiratory infections with a frequency of 14%. • Human Bocavirus genotype 1 is mainly detected in children of <5 months of age from the Amazon Region with acute gastroenteritis. • Human bocavirus genotype 2 is mainly detected in children of <5 months of age from the Amazon Region with acute respiratory infection. • Human Bocavirus genotype 1 DNA and Messenger RNA detected in fecal samples but not in saliva, is evidence of intestinal tract infection occurring in children of <5 months of age with acute gastroenteritis. This study aimed to verify the frequency, genotypes, and etiological role of Human Bocavirus (HBoV) in younger Amazonian children with either acute gastroenteritis (AGE) or respiratory infections (ARI). The influence of Rotarix™ vaccination and co-infection status was also investigated. HBoV quantitative polymerase chain reaction (qPCR) testing was done on both fecal and saliva (1468 samples) from 734 children < 5 months old living in the Amazon (Brazil, Guyana, and Venezuela). High and median HBoV viral load samples were used for extraction, nested PCR amplification, and sequencing for genotyping. HBoV mRNA detection was done by reverse transcription following DNA amplification. The overall HBoV frequencies were 14.2% (69/485; AGE) and 14.1% (35/249; ARI) (p = 0.83). HBoV exclusively infected 4.5% (22/485; AGE) and 4% (10/249) of the Amazonian children (Odds ratios 1.13, 95% confidence interval= 2.42-0.52). HBoV 1 was mainly detected in feces and saliva from AGE children; and HBoV2, from ARI children. HBoV mRNA was detected only in feces. The Rotarix™ vaccination status did not affect the HBoV frequencies. We suggest that, after entry into the air/oral pathways, HBoV1 continues infecting toward the intestinal tract causing AGE. HBoV2 can be a causative agent of AGE and ARI in younger Amazonian children. [ABSTRACT FROM AUTHOR]

Bothrops venezuelensis is a venomous snake of the Viperidae family. It is associated with a high snakebite-related morbidity and mortality in Venezuela, although clinical case descriptions are scarce. Bites by other Bothrops sp. can result in coagulopathy and acute kidney injury. We describe a bite by a captive juvenile B. venezuelensis that caused local swelling, severe pain, endothelial damage, excessive fibrinolysis (INR >12, aPTT 136s, fibrinogen 0.3g/l) and incoagulable blood within 1.5 hours after the bite. The patient was treated with prothrombin complex factors concentrate, fibrinogen and antivenom (Antivipmyn®, Instituto Bioclon, Mexico) 4.5 h after the bite, which improved coagulation parameters progressively. Subsequently signs of compensated disseminated intravascular coagulation manifested and the patient received fresh frozen plasma and erythrocyte concentrate. The patient developed acute kidney injury with macroscopic hematuria. Fluid overload resulted in pulmonary edema requiring intermittent ventilation and diuretic treatment with furosemide. He was discharged with moderately elevated creatinine 16 days after hospitalization. Creatinine level normalized within another week. This case displays the life-threatening toxicity even after juvenile B. venezuelensis bites and the comparability to bites by other Bothrops sp. • Describes a life-threatening envenomation by a juvenile Bothrops venezuelensis. • The patient developed severe hematotoxicity, acute kidney injury and pulmonary edema. • He was treated with antivenom and required intermittent non-invasive ventilation. • The toxicity profile of B. venezuelensis seems to be comparable to other Bothrops sp. [ABSTRACT FROM AUTHOR]

Nd3+/Ho3+/Yb3+ single-doped Ba 2 YV 3 O 11 near infrared (NIR) emitting phosphors were produced using sol-gel route, and their structures were determined by X-ray diffraction (XRD). The down conversion spectra, luminescence lifetime and energy transfer (ET) efficiency of samples have been investigated, which indicate that Ba 2 YV 3 O 11 : Nd3+/Ho3+/Yb3+ phosphors offer intense broad absorption band (250–400 nm) and emit efficient 900–1100 nm NIR emission where the crystal silicon solar cells display the optimal response. The ET processes from [VO 4 ]3- to dopants Nd3+/Ho3+/Yb3+ and possible ET mechanisms were also proposed in detail. Results showed that the Ba 2 YV 3 O 11 : Nd3+/Ho3+/Yb3+ phosphors were potential solar spectral converters for enhancing the silicon solar cell efficiency by absorption enhancement. Ba 2 YV 3 O 11 : RE3+ (RE = Nd, Ho, Yb) phosphors offer intense absorption (purple line), and emit efficient near-infrared light (shadow) in the maximal spectrum response of silicon solar cells. Image 1 • Ba 2 YV 3 O 11 : Nd3+/Ho3+/Yb3+ were prepared via sol-gel method. • As promising spectral converter, it can transform inefficient high-energy photons to practicable low-energy NIR photons. • The energy transfer processes were discussed and characterized between the hosts to activators. [ABSTRACT FROM AUTHOR]

• Rotavirus hospitalizations declined after vaccine introduction in PAHO countries. • Changes to rotavirus seasonality occurred post-vaccination and varied by country. • Various methods provide different advantages for quantifying vaccine impact. Passive surveillance data are often the only available source of data that can be used to evaluate the population-level impact of vaccination, but such data often suffer from important limitations such as changes in surveillance efforts. This study provides an example of how to identify important signatures of rotavirus vaccine impact, including evaluating the overall effectiveness and changes in rotavirus seasonal dynamics. We used data from a standardized sentinel rotavirus surveillance network in six Latin American countries (Bolivia, El Salvador, Guatemala, Honduras, Paraguay, and Venezuela) from 2004 to 2017. A random-effects model was used to evaluate changes in the proportion of rotavirus-associated hospitalizations following vaccine introduction. Harmonic regression models were used to estimate vaccine impact on the number of rotavirus hospitalizations, controlling for trends in rotavirus-negative cases. Changes to rotavirus seasonality were evaluated using center of gravity analysis, wavelet analysis, and harmonic regression. All countries observed declines in the proportion of rotavirus-positive acute diarrhea samples with a mean reduction of 16% (95% confidence interval: 10–22%). We estimate that each 10% increase in vaccine coverage was associated with declines in the number of rotavirus-positive cases, ranging from 4.3% (1.3–7.2%) in Honduras to 21.4% (16.8–25.9%) in Venezuela. The strength of the seasonal peak in rotavirus incidence became smaller after vaccine introduction in Guatemala, Honduras, and Venezuela. Seasonal peaks also shifted later in the surveillance year, especially in higher-mortality countries. The combination of methods we applied have different strengths that allow us to identify common signatures of rotavirus vaccine impact. [ABSTRACT FROM AUTHOR]

Tannery wastewater is characterized by high and variable concentrations of diverse pollutants, which makes it difficult and costly to treat. In the search for sustainable treatment options for tannery effluents, two pilot-scale horizontal subsurface flow (HSF) constructed wetlands (CW) were built and operated for the treatment of synthetic water of quality similar to that of pre-treated tannery effluents. Five different loading phases were examined with gradual increase of inflow COD, NH4+-N and Cr loads until reaching and exceeding the typical composition of a tannery effluent. High COD and NH4+-N removals were observed (82 and 96%, respectively), and almost complete Cr removal in the outflow, which met the Venezuela national standards for environmental discharge. Plant uptake was measured, but microbial processes appear to be the main ammonium transformation/removal mechanism. Nitrogen, chlorophyll and Cr in the plant aerial parts and roots indicated the capacity of Phragmites sp. to grow and survive even under high loads. The measured heterotrophic bacteria in the substrate and rhizomes indicated the biofilm development and the oxidation of organic matter and nitrogen. Water losses via evapotraspiration were also measured and reached 14%. Overall, the tested CW design proved to be a sustainable and feasible alternative for the treatment of tannery wastewater in tropical climates. Image 109 • Two pilot constructed wetlands for tannery wastewater under tropical climate. • High COD and NH 4 +-N removal (82–96%), complete Cr removal (99%) was found. • Plants assimilate part of nitrogen load, microbial processes remove most of ammonia. • Native plant proved to be tolerant to applied high pollutant loads. • Higher heterotrophic bacteria in the substrate and rhizosphere than outflow. [ABSTRACT FROM AUTHOR]

Quartz sandstone of the Sarisariñama massif in Venezuela hosts the world biggest collapse dolines in quartz-rich lithologies, with volumes up to some millions of cubic meters. Due to extremely complex logistics required to reach the massif, the genesis of these depressions and of the underlying caves has never been studied in detail. The lack of field campaigns and extended data has fostered a decade-long scientific debate on whether their origin was due to epigenic or hypogenic processes. This study integrates petrological, structural and hydrochemical observations, including analyses of silica concentration, pH, conductivity of surface and cave waters (EC), to investigate the speleogenetic processes acting underground. Petrographic and compositional analyses of the host rock (Matauí Formation) show that in the Sarisariñama region quartz sandstones are regularly characterized by clay interlayers with significant content of pyrophyllite and kaolinite and minor amount of iron hydroxides. Compared to surface waters, subsurface infiltration along vertical fractures and fault planes show enrichment in silica, higher pH and lower EC, confirming that chemical weathering is effective underground provoking intergranular silica dissolution along structural discontinuities. The weathering of the clay and iron hydroxide interlayers guides the speleogenesis, weakening specific stratigraphic levels and causing the collapse and fragmentation of the more resistant quartz sandstone strata. The initial void, created by piping of the loose sand released by quartz sandstone weathering, can migrate upwards by means of roof and wall breakdown; this chain of events eventually triggers a collapse at the surface, which generates a circular or squared sinkhole. The weathering acts mainly along the dominant fracture networks, showing a clear guidance by regional tectonics. These speleogenetic controls rule out the hypothesis of a hypogenic origin of the simas , suggesting a primary role of long-term epigenic chemical weathering and mechanical erosion guided by joints, weak clay and iron hydroxide interlayers, followed by subsequent massive collapses. [ABSTRACT FROM AUTHOR]

The expense of production and distribution of snakebite antivenom, as well as its relatively infrequent use, has caused antivenom to be increasingly difficult to obtain and ultimately producing an alarming global shortage. Unused, expired antivenom may represent a significant, untapped resource to ameliorate this crisis. This study examines the efficacy of expired antivenom over time using in vitro , whole blood clotting, and platelet function statistics. Representatives from three years for four different global brands of polyvalent antivenom were chosen and tested against their corresponding venoms as well as other venoms that could display cross-reactivity. These antivenoms include Wyeth Polyvalent (U.S.; exp. 1997, 2001, 2003), Antivipmyn® (Mexico; exp. 2005, 2013, 2017), Biotecfars Polyvalent (Venezuela; exp. 2010, 2014, 2016), and SAIMR (South Africa; exp. 1997, 2005, 2017). Venoms of species tested were Crotalus atrox against Wyeth; C. atrox and Crotalus vegrandis against Antivipmyn®; C. atrox , C. vegrandis and Bothrops colombiensis against Biotecfar; and Bitis gabonica and Echis carinatus against South African Institute for Medical Research (SAIMR). Parameters recorded were activated clotting time (ACT), clotting rate (CR), and platelet function (PF). Preliminary results are encouraging as the antivenoms maintained significant efficacy even 20 y after their expiration date. We anticipate these results will motivate further studies and provide hope in the cases of snakebite emergencies when preferable treatments are unavailable. • We tested the neutralizing efficacy of four global expired antivenoms. • Efficacy was tested in vitro using Sonoclot Coagulation & Platelet Function Analyzers. • Neutralization of venom activities on activated clot time, clot rate and platelet function were significant. • Antivenoms can maintain their efficacy 20 years after expiration. [ABSTRACT FROM AUTHOR]