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Reduced motivation is often noted as a consequence of cannabis use. However, previous work has yielded mixed results and focused largely on adults. To address these limitations, this study examined longitudinal associations between cannabis use and self-reported motivation in a large adolescent sample.
Participants were 401 adolescents aged 14–17 at baseline who completed five bi-annual assessments. We assessed motivation at three timepoints using two self-report questionnaires: the Apathy Evaluation Scale and the Motivation and Engagement Scale (disengagement, persistence, planning, self-efficacy, and valuing school subscales). Controlling for relevant covariates, we used latent growth curve modeling to characterize patterns of cannabis use and motivation over time, examining bidirectional influences between these processes.
On average, adolescent cannabis use frequency increased significantly over time. The disengagement and planning facets of motivation also increased significantly over time, whereas other aspects of motivation remained stable. At baseline, greater cannabis use was associated with greater disengagement, lower planning, and lower valuing of school. Greater baseline cannabis use also predicted lesser increases in disengagement over time. After controlling for the effect of sex, age, depression, and use of alcohol and nicotine, only the baseline association between cannabis use and valuing school remained significant.
Our results do not support a prospective link between cannabis use and reduced motivation among adolescents. Although most observed associations were accounted for by covariates, greater cannabis use was cross-sectionally associated with lower perceived value of school, which may contribute to poorer educational and later life outcomes.
Prior research has shown that sipping of alcohol begins to emerge during childhood and is potentially etiologically significant for later substance use problems. Using a large, community sample of 9- and 10-year-olds (N = 11,872; 53% female), we examined individual differences in precocious alcohol use in the form of alcohol sipping. We focused explicitly on features that are robust and well-demonstrated correlates of, and antecedents to, alcohol excess and related problems later in the lifespan, including youth- and parent-reported externalizing traits (i.e., impulsivity, behavioral inhibition and activation) and psychopathology. Seventeen percent of the sample reported sipping alcohol outside of a religiously sanctioned activity by age 9 or 10. Several aspects of psychopathology and personality emerged as small but reliable correlates of sipping. Nonreligious sipping was related to youth-reported impulsigenic traits, aspects of behavioral activation, prodromal psychotic-like symptoms, and mood disorder diagnoses, as well as parent-reported externalizing disorder diagnoses. Religious sipping was unexpectedly associated with certain aspects of impulsivity. Together, our findings point to the potential importance of impulsivity and other transdiagnostic indicators of psychopathology (e.g., emotion dysregulation, novelty seeking) in the earliest forms of drinking behavior.
In recent years, research has been focusing on strategies to counteract inflammatory processes and age-related diseases(1). During ageing, a low-grade systemic inflammation is often associated to an altered intestinal permeability (IP) a condition that has been shown to promote inflammation possibly through the translocation of dietary and bacterial factors into the blood stream that activates the immune system(2).In this regard, dietary pattern and environmental factors could play a fundamental role because of their potential ability to modulate inflammation, IP and the gut microbial ecosystem (GME). Moreover, it has been hypothesized that bioactive compounds such as polyphenols may affect IP and GME(3).The MaPLE project (Microbiome mAnipulation through Polyphenols for managing gut Leakiness in the Elderly) aimed to investigate the hypothesis that a polyphenol-rich diet can improve IP condition in a target population with beneficial changes at intestine and systemic level. To this aim, a randomised, controlled, cross-over dietary intervention study (8-week polyphenol-rich diet versus 8-week control diet, separated by a wash-out period) was carried out in a group of older subjects (> 60 years) living in a well-controlled setting (i.e. nursing home). Markers related with IP, inflammation, oxidative stress, vascular function and intestinal microbial ecosystem were investigated in serum, urine and/or fecal samples. Moreover, blood bacteria DNAemia, and serum/urine metabolomics has been assessed. Moreover, a consistent nutritional evaluation of the standard menu (provided by the nursing home) and of weighed food diaries was performed, providing also data on actual polyphenol intake during the intervention. The results show there were higher levels of IP in the older subjects, and that the polyphenol-enriched diet changed the levels of serum zonulin, a marker of IP. In addition, an association between zonulin and blood bacterial load was demonstrated. Ongoing in vitro and in vivo experiments are exploring the potential effects of different polyphenols on IP and the mechanisms involved. The MaPLE project will generate new data to improve the understanding on the role of polyphenols in the modulation of intestinal microbiome and its interactions with the host.
Objective: Relative to the vast literature that employs measures of decision-making (DM), rigorous examination of their psychometric properties is sparse. This study aimed to determine whether three measures of DM assess the same construct, and to measure invariance of this construct across relevant covariates. Method: Participants were 372 adolescents at risk of escalation in cannabis use. DM was assessed via four indices from the Cups Task, Game of Dice Task (GDT), and Iowa Gambling Task (IGT). We used confirmatory factor analysis to assess unidimensionality of the DM construct, and moderated nonlinear factor analysis (MNLFA) to examine its measurement invariance. Results: The unidimensional model of DM demonstrated good fit. MNLFA results revealed that sex influenced mean DM scores, such that boys had lower risk-taking behaviors. There was evidence of differential item functioning (DIF), such that IQ and age moderated the IGT intercept and GDT factor loading, respectively. Significant effects were retained in the final model, which produced participant-specific DM factor scores. These scores showed moderate stability over time. Conclusions: Indices from three DM tasks loaded significantly onto a single factor, suggesting that these DM tasks assess a single underlying construct. We suggest that this construct represents the ability to make optimal choices that maximize rewards in the presence of risk. Our final DM factor accounts for DIF caused by covariates, making it comparable across adolescents with different characteristics. (JINS, 2019, 25, 661–667)
Callous-unemotional (CU) traits are critical to developmental, diagnostic, and clinical models of antisocial behaviors (AB). However, assessments of CU traits within large-scale longitudinal and neurobiologically focused investigations remain remarkably sparse. We sought to develop a brief measure of CU traits using items from widely administered instruments that could be linked to neuroimaging, genetic, and environmental data within already existing datasets and future studies.
Data came from a large and diverse sample (n = 4525) of youth (ages~9–11) taking part in the Adolescent Brain and Cognitive Development (ABCD) Study. Moderated nonlinear factor analysis was used to assess measurement invariance across sex, race, and age. We explored whether CU traits were distinct from other indicators of AB, investigated unique links with theoretically-relevant outcomes, and replicated findings in an independent sample.
The brief CU traits measure demonstrated strong psychometric properties and evidence of measurement invariance across sex, race, and age. On average, boys endorsed higher levels of CU traits than girls and CU traits were related to, yet distinguishable from other indicators of AB. The CU traits construct also exhibited expected associations with theoretically important outcomes. Study findings were also replicated across an independent sample of youth.
In a large, multi-site study, a brief measure of CU traits can be measured distinctly from other dimensions of AB. This measure provides the scientific community with a method to assess CU traits in the ABCD sample, as well as in other studies that may benefit from a brief assessment of CU.
This work characterizes Late Cretaceous calc-alkaline volcanic rocks in Gastre, Northern Patagonia, Argentina. These newly found porphyritic rocks bear an 40Ar–39Ar amphibole age of ~ 74–76 Ma, a subduction-type geochemical signature and a deep, garnet-bearing source. Extruded in a stage of low magmatic activity in the Northern Patagonian Andes (~ 41–44° S), they could represent an eastward migration of the Late Cretaceous magmatic arc that was associated with a regional compressive deformational stage in the South American margin.
Cannabis use has been linked to impairments in neuropsychological functioning across a large and continually expanding body of research. Yet insight into underlying causal relations remains limited due to the historically cross-sectional nature of studies in this area. Recently, however, studies have begun to use more informative design strategies to delineate these associations. The aim of this article is to provide a critical evaluation and review of research that uses longitudinal designs to examine the link between cannabis use and neuropsychological functioning. In summarizing the primary findings across these studies, this review suggests that cannabis use leads to neuropsychological decline. However, across most studies, these associations were modest, were present only for the group with the heaviest cannabis use, and were often attenuated (or no longer significant) after controlling for potential confounding variables. Future studies with neuropsychological data before and after initiation of cannabis use, along with careful measurement and control of “shared risk factors” between cannabis use and poorer neuropsychological outcomes, are needed to better understand who, and under what conditions, is most vulnerable to cannabis-associated neuropsychological decline. (JINS, 2017, 23, 893–902)
With 30 threatened species (14 categorized as Critically Endangered and 16 as Endangered, sensu IUCN), Coccothrinax (c. 54 species) is the flagship palm genus for conservation in the Caribbean Island Biodiversity Hotspot. Coccothrinax has its centre of taxonomic diversity in these islands, with c. 51 endemic species. We present a conservation framework for the 14 Critically Endangered species, found in Cuba, Haiti or the Dominican Republic. Only two species (C. jimenezii, C. montana) occur in more than one country (Haiti and the Dominican Republic). Immediate threats include oil drilling and nickel mining, intrusion of saline water into soil, urban and agricultural development, low population recruitment, uncontrolled fires, interspecific hybridization, and unsustainable ethnobotanical practices. Coccothrinax bermudezii, C. borhidiana, C. crinita ssp. crinita, C. leonis and C. spissa are not conserved in protected areas. Coccothrinax bermudezii, C. jimenezii, C. leonis and C. nipensis are not part of ex situ collections. Based on results from a conservation project targeting C. jimenezii, we recommend international cooperation between the three range states to implement integrative conservation management plans, plant exploration initiatives, taxonomic revisions, outreach, and fundraising. The ultimate aim of this review is to provide baseline information that will develop conservation synergy among relevant parties working on Coccothrinax conservation in Cuba, Haiti and the Dominican Republic. Such collaborations could also benefit through partnerships with botanists working in other countries.
The Archive is the main Gaia data distribution hub. The contents of DR1 are briefly reviewed and the data structures discussed. The system architecture, based on Virtual Observatory standards, is also presented, together with the extensions that allow e.g. authenticated access, persistent uploads and table sharing. Finally some usage examples are provided.
Objectives: Engagement in risky sexual behavior (RSB) is a significant public health concern. A growing body of literature is elucidating the role of brain systems and neuropsychological constructs implicated in RSB, which may pave the way for novel insights and prevention efforts. Methods: In this article, we review studies incorporating neuropsychology into the study of RSB across the lifespan. The review of the literature on the neuropsychology of RSB is separated into three different sections by age of participants. Background is presented on research associating RSB with neurocognitive processes and the brain systems involved. Given the overlap between RSBs and substance use, studies addressing these problems in tandem are also discussed. Results: Neurocognitive constructs are implicated in RSB, including impulsivity, decision-making, and working memory. Discussion: Thus far, evidence suggest that neuropsychological factors are associated with engagement in RSB. More research on the influence of neuropsychological factors on engagement in RSB is necessary and may help inform future prevention efforts. (JINS, 2016, 22, 586–594)
In 2007, a partnership was initiated between a small-volume paediatric cardiac surgery unit located in Las Palmas de Gran Canaria, Spain, and a large-volume cardiac surgery unit located in Milan, Italy. The main goal of this partnership was to provide surgical treatment to children with CHD in the Canary Islands.
An operative algorithm for performing surgery in elective, urgent, and emergency cases was adopted by the this joint programme. Demographic and in-hospital variables were collected from the medical records of all the patients who had undergone surgical intervention for CHD from January, 2009 to March, 2013. Data were introduced into the congenital database of the European Congenital Heart Surgeons Association Congenital Database and the database was interrogated.
In total, 65 surgical mission trips were performed during the period of this study. The European Congenital Heart Surgeons Association Congenital Database documented 214 total patients with a mean age at operation of 36.45 months, 316 procedures in total with 198 cardiopulmonary bypass cases, 46 non-cardiopulmonary bypass cases, 26 cardiovascular cases without cardiopulmonary bypass, 22 miscellaneous other types of cases, 16 interventional cardiology cases, six thoracic cases, one non-cardiac, non-thoracic procedure on a cardiac patient with cardiac anaesthesia, and one extracorporeal membrane oxygenation case. The 30-day mortality was 6.07% (13 patients).
A joint programme between a small-volume centre and a large-volume centre may represent a valid and reproducible model for safe paediatric cardiac surgery in the context of a peripheral region.
Objectives: Results from research conducted on the association between cannabis use and body mass index (BMI) reveal mixed findings. It is possible that individual differences in decision-making (DM) abilities may influence these associations. Methods: This study analyzed how amount of cannabis use, DM performance, and the interaction of these variables influenced BMI and clinical classifications of weight among adolescents (ages 14 to 18 years; 56% male; 77% Hispanic). The sample consisted primarily of cannabis users (n=238) without a history of significant developmental disorders, birth complications, neurological conditions, or history of mood, thought, or attention deficit/hyperactivity disorder at screening. Furthermore, few participants engaged frequently in other drug use (except for alcohol and nicotine). Results: Analyses revealed that more lifetime cannabis use was associated with a higher BMI and greater likelihood of being overweight/obese. Interactions between DM and cannabis use on BMI were not significant, and DM was not directly associated with BMI. Discussion: Our findings suggest that among adolescents, cannabis use is associated with a greater BMI regardless of DM abilities and this association is not accounted for by other potential factors, including depression, alcohol use, nicotine use, race, ethnicity, or IQ. (JINS, 2016, 22, 944–949)
The preliminary results of an analysis of the time-series photometric data of binary star GSC 02049-01164 (ROTSE1 J164341.65+251748.1) are presented. GSC 02049-01164 was observed for eight consecutive nights with the 0.84-m telescope of the San Pedro Martir Observatory in Mexico. The light curve of GSC 02049-01164 is typical of those of W UMa type binary stars. In an effort to gain a better understanding of the binary system and determine its physical properties we have analyzed the light curve with the software PHOEBE V.0 0.31a. We have found that GSC 02049-01164 binary system has a mass ratio of ~ 0.42, an inclination of ~ 85 degrees, a semi-major axis of ~ 2.24 R⊙. It is likely that the two stellar components are in contact, with a degree of overcontact of 13%. The physical parameters of the stellar components have been derived.
The composition and structure of sublittoral faunal assemblages inhabiting soft bottoms (15–72 m depth) within the Marine Protected Area ‘Acantilados y Fondos Marinos de Calahonda-Castell de Ferro’ in southern Spain (North Alboran Sea, Mediterranean) have been studied in relation to sediment and water column variables. Three assemblages were identified and corresponded to mixed bottom, unstable bottom and coastal detritic bottom assemblages, based on Pérès & Picard's (1964) benthic classification. A total of 14,318 individuals were collected and 218 species identified, molluscs being the best represented group (141 species). Species richness displayed significant differences with depth and transect, with the highest values observed in the medium to very fine sand and muddy bottoms with bioclasts located at the shallowest sampling stations. The presence of some rare and poorly known invertebrates that are scarce in other areas of the Mediterranean Sea is remarkable, such as the crustacean decapods Bythocaris cosmetops and Pagurus mbizi, Atlantic species with no records in the Mediterranean Sea, and the bathyal molluscs Poromya granulata and Alvania testae, collected at shallow depths. The spatial distribution of faunal assemblages was mainly related to depth and percentage of gravel and clay according to the canonical correspondence analysis. The geographic location of the area, the heterogeneity of soft bottoms and the presence of upwellings in the area may favour the high biodiversity found in the studied soft bottoms. This study increases the scarce knowledge of the circalittoral fauna of sedimentary habitats of the Alboran Sea, providing a baseline for the management of this interesting SCI and for the EU Marine Strategy Framework Directive.
The archaeological site of Tlatoani at Tlayacapan is located in the Mexican Highlands, in the present-day state of Morelos. The site is an extant settlement located at the top of the Tepoztlan mountain range, and has been occupied since the Late Preclassic period (AD 150–500). At the height of its occupation in the Epiclassic and Early Postclassic periods (AD 600–1150), Tlayacapan was situated on the top of the hill. The radiocarbon investigations reported herein revealed some further distinct findings, although no clear absolute chronology was demonstrated. A dog skull was found inside the oldest foundation stage, and dated between cal AD 646 and 765, the middle of the Epiclassic period. Human remains found in the first grave belonged to three individuals. A male skeleton was dated to AD 1158–1227. Fragments of an incomplete skeleton of a child and an incomplete skeleton of a second male were placed on top of the first male skeleton and were dated in the range AD 1030–1156. A fourth skeleton found nearby in the second grave gave a similar date of AD 1164–1253. These burials were in accordance with the Middle America cosmovisional system, where bodies were buried beneath the household space. It is evident from the 14C dates of the skeletons that the burial sites beneath the household space had been reused by exhuming and reburying skeletons that had been previously buried there. A comparison of dates on fractions of collagen and bioapatite of the same bones was possible. Two of the samples were in good agreement between these fractions, whereas the other three samples are close but just outside the 2σ range.
Accumulating evidence suggests neuropsychological deficits from cannabis use, with a burgeoning area of preclinical research indicating possible sex-differences. However, few studies have examined how cannabis use may differentially impact neurocognition in male and female cannabis users. As such, we examined potential sex-differences in associations between amount of cannabis use (across several time frames) and neurocognitive performance among young adult regular cannabis users. Consistent with previous studies, more cannabis use was generally associated with poorer episodic memory and decision-making, but not other measures of inhibitory control. However, patterns of results suggested sex-specific dissociations. In particular, more cannabis use was more consistently associated with poorer episodic memory performance in females than males. Conversely, more cannabis use was associated with poorer decision-making performance for males, but not females. These results provide further evidence for residual cannabis-associated neurocognitive deficits and suggest the importance of examining the impact of cannabis on neurocognition separately for males and females. (JINS, 2013, 19, 1–7)
The abundance and distribution of coastal cephalopods are strongly influenced by the environmental conditions. This study evaluates the seasonal distribution and density of Octopus tehuelchus in three intertidal environments of San Matías Gulf (Patagonia). To estimate and compare density and distribution, monthly transects were carried out, and analysed in relation to the coastlines obtained with satellite images. Densities of O. tehuelchus ranged between 0 and 34 individuals per transect (0–0.11 octopus m−2), and varied between sites. Islote Lobos (IL) had the highest densities (mean octopus per transect 7.32 ± 1.16) followed by El Fuerte (EF) (5.55 ± 0.94) and San Antonio Bay (SAB) (3.40 ± 0.85). Within each site, octopus densities varied between seasons. The highest densities were observed during warm months (SAB = 5.96, EF = 9.52, IL = 14.15) and the lowest during cold ones (SAB = 1.45, EF = 2.6, IL = 3.32). Octopus tehuelchus showed an aggregated spatial distribution, and the nearest neighbour value varied between 0.21 and 0.83 in SAB, 0.27 and 0.78 in EF and 0.23 and 0.53 in IL. Considering the coast lines, the distribution pattern along the intertidal varied seasonally. During warm months this species is widely distributed throughout the intertidal, from the low-tide line to 300 m (in SAB), 500 m (in EL) and 200 m (in IL). On the contrary, during cold months most individuals were found near the low-tide line. These results may be associated with the availability of shelter in the intertidal and the activity and physiology of this species.