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Cognition heavily relies on social determinants and genetic background. Latin America comprises approximately 8% of the global population and faces unique challenges, many derived from specific demographic and socioeconomic variables, such as violence and inequality. While such factors have been described to influence mental health outcomes, no large-scale studies with Latin American population have been carried out. Therefore, we aim to describe the cognitive performance of a representative sample of Latin American individuals with schizophrenia and its relationship to clinical factors. Additionally, we aim to investigate how socioeconomic status (SES) relates to cognitive performance in patients and controls.
We included 1175 participants from five Latin American countries (Argentina, Brazil, Chile, Colombia, and Mexico): 864 individuals with schizophrenia and 311 unaffected subjects. All participants were part of projects that included cognitive evaluation with MATRICS Consensus Cognitive Battery and clinical assessments.
Patients showed worse cognitive performance than controls across all domains. Age and diagnosis were independent predictors, indicating similar trajectories of cognitive aging for both patients and controls. The SES factors of education, parental education, and income were more related to cognition in patients than in controls. Cognition was also influenced by symptomatology.
Patients did not show evidence of accelerated cognitive aging; however, they were most impacted by a lower SES suggestive of deprived environment than controls. These findings highlight the vulnerability of cognitive capacity in individuals with psychosis in face of demographic and socioeconomic factors in low- and middle-income countries.
Migratory species rely on several distant sites during the annual cycle which makes their conservation more complex than that of non-migratory species. Even one of the most extensively studied migratory shorebirds - the Red Knot Calidris canutus - is currently ‘Near Threatened’ at the global level. Conflicting observations of migratory routes cast uncertainty on the subspecies classification and migratory connectivity of Red Knots in the Pacific coasts of the Americas. To fill essential information gaps, we present the first detailed population morphometrics of Red Knots during the non-breeding season in the southern Pacific coast, along with resightings of these birds throughout the Americas. We also estimated daily rate of weight gain during fuelling based on body mass at captures and known departure dates. Resightings demonstrate reliance on staging areas in both the Mid-continental and Atlantic flyways during the northward migration, and additionally in the Pacific Flyway during southward migration. In addition to the strong connection with several areas also used by C. c. rufa on the North American Atlantic coast, our results show morphometric differences within the ranges of both C. c. rufa and C. c. roselaari. Given the threats faced by Red Knots, the population in Chiloé Archipelago should be treated as a separate conservation unit within interhemispheric conservation programmes for endangered shorebirds within the Americas.
Contrasting perspectives on racism and racial inequality collide in contemporary Cuba. On the one hand, government officials argue that Cuba is a racially egalitarian country; though vestiges of historical racism subsist, systematic discrimination does not. On the other hand, social movement actors and organizations denounce that racism and discrimination are systemic and affect large sectors of the Afro-Cuban population. To draw these visions into scholarly dialogue, our analytic strategy consists in the comparative examination of both narratives as well as the empirical bases that sustain them. Using data from the 1981, 2002, and 2012 Cuban Censuses for the first time, as well as various non-census evidentiary sources, both quantitative and qualitative, we examine how racial inequality has evolved in Cuba during the last decades. Our analyses of census data suggest that racial stratification has a limited impact on areas such as education, health care, occupation, and positions of leadership. We find, nonetheless, that an expanding and strikingly racialized private sector is fueling dramatic income inequality by skin color beyond the reach of official census data. Our analysis sheds light on how different data can convey profoundly different pictures of racial inequality in a given context. Moreover, we highlight that significant contradictions can coexist in the lived experiences of racism and racial inequality within a single country context.
Crop–weed interactions are affected by environmental alterations resulting from a crop’s presence, such as modifications in temperature, light quality and quantity, and moisture conditions that could modify weed performance. The objectives of this work were to study (1) how soybean [Glycine max (L.) Merr.] crop structure modifies the environment under the canopy and large crabgrass [Digitaria sanguinalis (L.) Scop.] plant structure, biomass, and seed production and dormancy; and (2) the relative importance of these environmental changes on the weed’s characteristics. A field experiment in a completely randomized block design with five replicates was performed to evaluate narrow and wide interrow spacing and soybean maturity groups 3 and 4. Measured variables were intercepted solar radiation (RAD); red–far red (R-FR) ratio; humidity; minimum, maximum, and alternating temperatures; and weed biomass, tillers per plant, height, and seed dormancy. Crop canopy reduced solar radiation, R-FR ratio, and daily average maximum and alternating temperatures. Soybean presence reduced the weed biomass, tillers and seeds per plant, and seed dormancy. High solar radiation intercepted by the crop during the reproductive phase was the main environmental variable related to reductions in weed biomass, tillers per plant, and fecundity. The combination of low temperature and solar radiation received by developing seeds was more related to seed dormancy than the rest of the variables. Crop management decisions focused on the fact that keeping the crop canopy alive for a longer time at the end of the season would not only reduce the weed growth but also seed dormancy.
The use of global positioning system (GPS) units attached to collars is becoming increasingly common in primate studies (Anderson, pers. comm.; Crofoot et al. 2014; Di Fiore & Link 2013; Dore, pers. comm.; Klegarth et al. 2017; Markham & Altmann 2008; Markham et al. 2013; Sprague et al. 2004; Stark, pers. comm.). By deploying GPS collars, researchers can gain enhanced knowledge of primate group whereabouts and overall ranging and landscape use patterns at a high resolution (Crofoot et al. 2014). The utility of these systems has greatly expanded with the increasing spatial accuracy, reliability, and mechanisms (remote data download and drop-off units) of units that facilitate reasonably low impact on study animals (Klegarth et al. 2017; Matthews et al. 2013). While these collars open up new methodological and analytic possibilities for assessing primate ranging patterns and habitat use, they also present a diverse array of technical, structural, and ethical concerns with doing so (Hebblewhite & Haydon 2010; Todd & Shah 2012)
Climate change is predicted to increase the frequency of extreme weather events, increasing the vulnerability of smallholder farmers dependent on rain-fed agriculture. We evaluate the extent to which farmers in Malawi suffer crop production losses due to extreme weather, and whether sustainable land management (SLM) practices help shield crop production losses from extreme events. We use a three period panel dataset where widespread floods and droughts occurred in separate periods, offering a unique opportunity to evaluate impacts using data collected immediately following these events. Results show that crop production outcomes were severely hit by both floods and droughts, with average losses ranging between 32–48 per cent. Legume intercropping provided protection against both floods and droughts, while green belts provided protection against floods. However, we find limited evidence that SLM adoption decisions are driven by exposure to weather shocks; rather, farmers with more productive assets are more likely to adopt.
Liquefied natural gas (LNG) offers negligible NOx and SOx emissions as well as reductions in CO2 compared with other liquid hydrocarbons. LNG is a significant player in the global energy mix, with a projection of 40% increase in demand for the next two decades. It is anticipated that the expected rise in demand will cause the fleet of LNG carriers (LNGC) to expand. This work concentrates on steam-powered LNGC, which accounted for 47% of the LNGC fleet in 2018. It performs an empirical analysis of continuous monitoring data that provide high levels of accuracy and transparency. The analysis is done on data collected from 40 LNGCs for over a year to estimate the fleet's operational profile, fuel mix and energy performance. The findings of this work are relevant for bottom-up analysis and simulation models that depend on technical assumptions, but also for emission studies such as the upcoming Fourth International Maritime Organization Greenhouse Gases study.
This study analyzes the effects of the Pedernales earthquake (April 2016) on Ecuador’s health care system.
A research was carried out in Chone Canton, which combined documentary, quantitative, and qualitative techniques. Epidemiological and service production information taken from official documents was analyzed systematically. In-depth interviews and surveys were conducted with health care program directors and technicians from the Health Centres of the Ministry of Public Health and the users.
Deficiencies in the health care system were already observed in Chone Canton prior to the earthquake mainly due to the lack of doctors, nurses, and hospital beds. According to the interviewees, the health district was not prepared for an emergency like the earthquake. Some buildings fell after the earthquake, and Chone Hospital was disabled. These problems coupled with preventive action failures at the community level led to an increase in diseases after the earthquake.
The shortage of personnel and physical infrastructure, weaknesses in primary health care in the Ecuadorian health system, the lack of preparation, and limited availability of information on health indicators were the causes of the sharp increase in pre-existing diseases in the area, and of new epidemic outbreaks after the earthquake.
The aging process is associated with a deterioration of the physiological systems, especially the homeostatic (nervous, immune and endocrine) systems with the consequent increase in morbidity and mortality. With the aging population, increasing number of studies focus on lifestyle interventions to slow down these aging derangements. Here, animal models can be useful to assess their long-term effects and potential value taking into advantage their shorter life span. In a previous work, old animals beneficed of 2 months of continuous cohabitation with adult, with improvements on behaviour, immune function and redox state as well as a higher longevity. However, their adult counterparts showed impairments in these parameters. In the present study, this social strategy was modified with the aim to improve the homeostatic systems in both the old and the adult animals.) Animals of the experimental group with “two old ICR-CD1 female mice cohabiting 15 minutes each day for 2 months with five adult mic” were studied and compared to adult and old controls. After this time, mice were submitted to a behavioural battery of tests to analyse their sensorimotor abilities, anxiety-like behaviours, and exploratory capacities. Peritoneal leukocytes were collected and several immune functions, oxidative and inflammatory stress parameters as well as catecholamine concentrations were assessed. When the adult mice reached old age the same parameters were again analysed. The life span of each animal was also recorded. Several mice of each group were sacrificed to obtain plasma and the hormone oxytocin was evaluated. The results show that old mice presented an improvement of behavioural capacities, immune functions and lower oxidative and inflammatory stress after the two months of social interaction with adult animals, and consequently they exhibited an extended life span. Adult mice, in general, did not show any changes after social interaction, but when they achieved old age an improvement of all the parameters studied and of longevity was observed in comparison with those mice that never had a social interaction with old animals. In conclusion, a short social interaction between old and adult individuals can be an excellent strategy for improving in both the health state and longevity.
Evaluate the relevance of the coronavirus disease 2019 (COVID-19) positive case detection policy or model implemented by the Ministry of Public Health (MPH) of Ecuador and to compare it with the experiences of other countries.
Data contained the daily reports publicized by the MPH. The formulations were carried out under the Conditioned Probability modality applying Bayes’ Theorem. All the COVID-19 tests applied in relation to the confirmed cases per million inhabitants were considered to obtain their level of positivity, and compared with the experience of Iceland and South Korea.
The probability of detecting positive cases of COVID-19 in Ecuador was higher than Iceland and South Korea, because the diagnostic tests were aimed at symptomatic patients, without identifying asymptomatic or mild symptomatic, who play an important role in the transmission of the disease. In addition, many symptomatic patients were examined but will remain undiagnosed due to the unavailability of tests and the low quality of many of them.
The daily reports on the behavior of the COVID-19 issued by the Ecuadorian government do not adequately represent the growth in the number of those infected each day, nor the actual behavior of the epidemic, affecting possible control measures.
The coronavirus disease 2019 (COVID-19) pandemic has induced a reinforcement of infection control measures in the hospital setting. Here, we assess the impact of the COVID-19 pandemic on the incidence of nosocomial Clostridioides difficile infection (CDI).
We retrospectively compared the incidence density (cases per 10,000 patient days) of healthcare-facility–associated (HCFA) CDI in a tertiary-care hospital in Madrid, Spain, during the maximum incidence of COVID-19 (March 11 to May 11, 2020) with the same period of the previous year (control period). We also assessed the aggregate in-hospital antibiotic use (ie, defined daily doses [DDD] per 100 occupied bed days [BD]) and incidence density (ie, movements per 1,000 patient days) of patient mobility during both periods.
In total, 2,337 patients with reverse transcription-polymerase chain reaction–confirmed COVID-19 were admitted to the hospital during the COVID-19 period. Also, 12 HCFA CDI cases were reported at this time (incidence density, 2.68 per 10,000 patient days), whereas 34 HCFA CDI cases were identified during the control period (incidence density, 8.54 per 10,000 patient days) (P = .000257). Antibiotic consumption was slightly higher during the COVID-19 period (89.73 DDD per 100 BD) than during the control period (79.16 DDD per 100 BD). The incidence density of patient movements was 587.61 per 1,000 patient days during the control period and was significantly lower during the COVID-19 period (300.86 per 1,000 patient days) (P < .0001).
The observed reduction of ~70% in the incidence density of HCFA CDI in a context of no reduction in antibiotic use supports the importance of reducing nosocomial transmission by healthcare workers and asymptomatic colonized patients, reinforcing cleaning procedures and reducing patient mobility in the epidemiological control of CDI.
Social and environmental factors such as poverty or violence modulate the risk and course of schizophrenia. However, how they affect the brain in patients with psychosis remains unclear.
We studied how environmental factors are related to brain structure in patients with schizophrenia and controls in Latin America, where these factors are large and unequally distributed.
This is a multicentre study of magnetic resonance imaging in patients with schizophrenia and controls from six Latin American cities. Total and voxel-level grey matter volumes, and their relationship with neighbourhood characteristics such as average income and homicide rates, were analysed with a general linear model.
A total of 334 patients with schizophrenia and 262 controls were included. Income was differentially related to total grey matter volume in both groups (P = 0.006). Controls showed a positive correlation between total grey matter volume and income (R = 0.14, P = 0.02). Surprisingly, this relationship was not present in patients with schizophrenia (R = −0.076, P = 0.17). Voxel-level analysis confirmed that this interaction was widespread across the cortex. After adjusting for global brain changes, income was positively related to prefrontal cortex volumes only in controls. Conversely, the hippocampus in patients with schizophrenia, but not in controls, was relatively larger in affluent environments. There was no significant correlation between environmental violence and brain structure.
Our results highlight the interplay between environment, particularly poverty, and individual characteristics in psychosis. This is particularly important for harsh environments such as low- and middle-income countries, where potentially less brain vulnerability (less grey matter loss) is sufficient to become unwell in adverse (poor) environments.
When the United States invaded Nicaragua in 1912 the popular reaction in El Salvador was so strong that it completely upended politics. The article argues that this anti-imperialist movement, completely ignored by the current historiography, forced Salvadorean governments to make decisions regarding foreign policy that would have been unthinkable had it not been for the pressure from below. Popular pressures contributed to limit the scope of the final version of the Chamorro–Bryan Treaty between the United States and Nicaragua. The treaty did not include Platt Amendment-like provisions. Moreover, the Wilson administration abandoned the idea of extending a protectorate to all the Central American countries and building a naval base in the Gulf of Fonseca.
Humans can see the world around them, imagine how it might be different, and translate those imaginings into reality ‥ or at least try to. This ability plays a significant role in our lineage’s evolutionary success. Meaning, imagination, and hope are as central to the human evolutionary story as are bones, genes, and ecologies. Paleoanthropological, archaeological, and biological data make it abundantly clear that the human lineage, over the last 2 million years, has undergone specific morphological changes alongside less easily measurable, but significant behavioral and cognitive shifts as it has forged and been shaped by a new niche, a highly distinctive way of being in the world – a human niche, a niche in which imagination is a key factor. This chapter offers a brief overview of this history and highlights how developmental processes of the human body and brain evolve as a system that is always in concert with, and mutually co-constitutive of, the linguistic, socially mediated and constructed structures, institutions, and beliefs that make up key aspects of the human niche.
In Chile, two quinoa ecotypes are grown: salares, also present in the highlands of Bolivia, and coastal, in central and southern areas of the country, at sea level. Genotypes from the coastal ecotype have characteristics that differentiate them from the most popular quinoa genotypes grown in the Andean Region of South America. The objectives of this study were: (1) to determine the cardinal temperatures for seed germination in quinoa genotypes from coastal and salares ecotypes cultivated in Chile, and (2) to study the presence of physiological dormancy (PD) in these genotypes. Seed germination from nine quinoa genotypes, two from salares and seven from coastal ecotypes, was evaluated in a gradient of temperatures between 11 and 42°C. Germination was also evaluated at 20°C at 0, 7 and 15 months from harvest. Results showed that seed from the nine genotypes germinated at their maximum percentage between 11 and 35°C. However, their faster germination occurred between 25 and 35°C. There was a significant difference between optimum temperature for germination between genotypes from coastal (28°C) and salares (30°C). An increase in germination rates after 7 months of storage suggested the presence of a non-deep PD in seeds from coastal ecotype, which may be useful to improve pre-harvest sprouting resistance in quinoa breeding programmes.
The giant gypsum crystals of Naica cave have fascinated scientists since their discovery in 2000. Human activity has changed the microclimate inside the cave, making scientists wonder about the potential environmental impact on the crystals. Over the last 9 years, we have studied approximately 70 samples. This paper reports on the detailed chemical–structural characterization of the impurities present at the surface of these crystals and the experimental simulations of their potential deterioration patterns. Selected samples were studied by petrography, optical and electronic microscopy, and laboratory X-ray diffraction. 2D grazing incidence X-ray diffraction, X-ray μ-fluorescence, and X-ray μ-absorption near-edge structure were used to identify the impurities and their associated phases. These impurities were deposited during the latest stage of the gypsum crystal formation and have afterward evolved with the natural high humidity. The simulations of the behavior of the crystals in microclimatic chambers produced crystal dissolution by 1–4% weight fraction under high CO2 concentration and permanent fog, and gypsum phase dehydration under air and CO2 gaseous environment. Our work suggests that most surface impurities are of natural origin; the most significant anthropogenic damage on the crystals is the extraction of water from the caves.