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1.
Nature ; 569(7757): E8, 2019 May.
Artículo en Inglés | MEDLINE | ID: mdl-31065057

RESUMEN

Change history: In Fig. 2b of this Letter, 'Relative wetland change (km2)' should have read 'Relative wetland change (%)' and equations (2) and (3) have been changed from 'RSLRcrit = (m × TRe) × Sed + i' and 'Sedcrit = (RSLR - i)/(m × TRe)', respectively. The definition of the variables in equation (2) has been updated. These errors have been corrected online.

2.
Nature ; 561(7722): 231-234, 2018 09.
Artículo en Inglés | MEDLINE | ID: mdl-30209368

RESUMEN

The response of coastal wetlands to sea-level rise during the twenty-first century remains uncertain. Global-scale projections suggest that between 20 and 90 per cent (for low and high sea-level rise scenarios, respectively) of the present-day coastal wetland area will be lost, which will in turn result in the loss of biodiversity and highly valued ecosystem services1-3. These projections do not necessarily take into account all essential geomorphological4-7 and socio-economic system feedbacks8. Here we present an integrated global modelling approach that considers both the ability of coastal wetlands to build up vertically by sediment accretion, and the accommodation space, namely, the vertical and lateral space available for fine sediments to accumulate and be colonized by wetland vegetation. We use this approach to assess global-scale changes in coastal wetland area in response to global sea-level rise and anthropogenic coastal occupation during the twenty-first century. On the basis of our simulations, we find that, globally, rather than losses, wetland gains of up to 60 per cent of the current area are possible, if more than 37 per cent (our upper estimate for current accommodation space) of coastal wetlands have sufficient accommodation space, and sediment supply remains at present levels. In contrast to previous studies1-3, we project that until 2100, the loss of global coastal wetland area will range between 0 and 30 per cent, assuming no further accommodation space in addition to current levels. Our simulations suggest that the resilience of global wetlands is primarily driven by the availability of accommodation space, which is strongly influenced by the building of anthropogenic infrastructure in the coastal zone and such infrastructure is expected to change over the twenty-first century. Rather than being an inevitable consequence of global sea-level rise, our findings indicate that large-scale loss of coastal wetlands might be avoidable, if sufficient additional accommodation space can be created through careful nature-based adaptation solutions to coastal management.


Asunto(s)
Mapeo Geográfico , Calentamiento Global/estadística & datos numéricos , Modelos Teóricos , Agua de Mar/análisis , Humedales , Calibración , Sedimentos Geológicos/análisis , Actividades Humanas , Internacionalidad
3.
Mol Psychiatry ; 27(2): 1167-1176, 2022 02.
Artículo en Inglés | MEDLINE | ID: mdl-34707236

RESUMEN

Neuroanatomical abnormalities have been reported along a continuum from at-risk stages, including high schizotypy, to early and chronic psychosis. However, a comprehensive neuroanatomical mapping of schizotypy remains to be established. The authors conducted the first large-scale meta-analyses of cortical and subcortical morphometric patterns of schizotypy in healthy individuals, and compared these patterns with neuroanatomical abnormalities observed in major psychiatric disorders. The sample comprised 3004 unmedicated healthy individuals (12-68 years, 46.5% male) from 29 cohorts of the worldwide ENIGMA Schizotypy working group. Cortical and subcortical effect size maps with schizotypy scores were generated using standardized methods. Pattern similarities were assessed between the schizotypy-related cortical and subcortical maps and effect size maps from comparisons of schizophrenia (SZ), bipolar disorder (BD) and major depression (MDD) patients with controls. Thicker right medial orbitofrontal/ventromedial prefrontal cortex (mOFC/vmPFC) was associated with higher schizotypy scores (r = 0.067, pFDR = 0.02). The cortical thickness profile in schizotypy was positively correlated with cortical abnormalities in SZ (r = 0.285, pspin = 0.024), but not BD (r = 0.166, pspin = 0.205) or MDD (r = -0.274, pspin = 0.073). The schizotypy-related subcortical volume pattern was negatively correlated with subcortical abnormalities in SZ (rho = -0.690, pspin = 0.006), BD (rho = -0.672, pspin = 0.009), and MDD (rho = -0.692, pspin = 0.004). Comprehensive mapping of schizotypy-related brain morphometry in the general population revealed a significant relationship between higher schizotypy and thicker mOFC/vmPFC, in the absence of confounding effects due to antipsychotic medication or disease chronicity. The cortical pattern similarity between schizotypy and schizophrenia yields new insights into a dimensional neurobiological continuity across the extended psychosis phenotype.


Asunto(s)
Trastorno Bipolar , Trastornos Psicóticos , Esquizofrenia , Trastorno de la Personalidad Esquizotípica , Femenino , Humanos , Imagen por Resonancia Magnética/métodos , Masculino , Trastornos Psicóticos/diagnóstico por imagen , Trastorno de la Personalidad Esquizotípica/diagnóstico por imagen
4.
J Trauma Stress ; 35(2): 461-472, 2022 04.
Artículo en Inglés | MEDLINE | ID: mdl-34811818

RESUMEN

Many returning military service members and veterans who were deployed following the September 11, 2001, terrorist attacks (9/11) suffer from posttraumatic stress disorder (PTSD) and insomnia. Although intensive treatment programs for PTSD have shown promise in the treatment of PTSD symptoms, recent research has demonstrated that sleep disturbance shows little improvement following intensive trauma-focused treatment. The aim of the present study was to evaluate changes in self-reported insomnia symptoms among veterans and service members following participation in a 2-week intensive program for PTSD. We further aimed to investigate if residual PTSD symptoms, specifically hyperarousal, were associated with residual insomnia symptoms. Participants (N = 326) completed self-report assessments of insomnia, PTSD symptoms, and depressive symptoms at pre- and posttreatment. At pretreatment, 73.9% of participants (n = 241) met the criteria for moderate or severe insomnia, whereas at posttreatment 67.7% of participants (n = 203) met the criteria. Results of paired t tests demonstrated statistically significant differences between pre- and posttreatment Insomnia Severity Index scores; however, the effect size was small, d = 0.34. Analyses revealed that posttreatment hyperarousal symptoms were associated with posttreatment insomnia. These findings suggest that although an intensive program for service members and veterans with PTSD may significantly reduce insomnia symptoms, clinically meaningful residual insomnia symptoms remain. Further research is warranted to elucidate the association between residual hyperarousal and insomnia symptoms following intensive trauma-focused treatment.


Asunto(s)
Trastornos del Inicio y del Mantenimiento del Sueño , Trastornos por Estrés Postraumático , Veteranos , Nivel de Alerta , Progresión de la Enfermedad , Humanos , Pacientes Ambulatorios , Trastornos del Inicio y del Mantenimiento del Sueño/complicaciones , Trastornos del Inicio y del Mantenimiento del Sueño/terapia , Trastornos por Estrés Postraumático/complicaciones , Trastornos por Estrés Postraumático/diagnóstico , Trastornos por Estrés Postraumático/terapia
5.
J Neurosci ; 37(7): 1708-1720, 2017 02 15.
Artículo en Inglés | MEDLINE | ID: mdl-28202786

RESUMEN

Learning to optimally predict rewards requires agents to account for fluctuations in reward value. Recent work suggests that individuals can efficiently learn about variable rewards through adaptation of the learning rate, and coding of prediction errors relative to reward variability. Such adaptive coding has been linked to midbrain dopamine neurons in nonhuman primates, and evidence in support for a similar role of the dopaminergic system in humans is emerging from fMRI data. Here, we sought to investigate the effect of dopaminergic perturbations on adaptive prediction error coding in humans, using a between-subject, placebo-controlled pharmacological fMRI study with a dopaminergic agonist (bromocriptine) and antagonist (sulpiride). Participants performed a previously validated task in which they predicted the magnitude of upcoming rewards drawn from distributions with varying SDs. After each prediction, participants received a reward, yielding trial-by-trial prediction errors. Under placebo, we replicated previous observations of adaptive coding in the midbrain and ventral striatum. Treatment with sulpiride attenuated adaptive coding in both midbrain and ventral striatum, and was associated with a decrease in performance, whereas bromocriptine did not have a significant impact. Although we observed no differential effect of SD on performance between the groups, computational modeling suggested decreased behavioral adaptation in the sulpiride group. These results suggest that normal dopaminergic function is critical for adaptive prediction error coding, a key property of the brain thought to facilitate efficient learning in variable environments. Crucially, these results also offer potential insights for understanding the impact of disrupted dopamine function in mental illness.SIGNIFICANCE STATEMENT To choose optimally, we have to learn what to expect. Humans dampen learning when there is a great deal of variability in reward outcome, and two brain regions that are modulated by the brain chemical dopamine are sensitive to reward variability. Here, we aimed to directly relate dopamine to learning about variable rewards, and the neural encoding of associated teaching signals. We perturbed dopamine in healthy individuals using dopaminergic medication and asked them to predict variable rewards while we made brain scans. Dopamine perturbations impaired learning and the neural encoding of reward variability, thus establishing a direct link between dopamine and adaptation to reward variability. These results aid our understanding of clinical conditions associated with dopaminergic dysfunction, such as psychosis.


Asunto(s)
Adaptación Fisiológica/fisiología , Cuerpo Estriado/metabolismo , Mesencéfalo/metabolismo , Adaptación Fisiológica/efectos de los fármacos , Adulto , Bromocriptina/farmacología , Simulación por Computador , Cuerpo Estriado/diagnóstico por imagen , Cuerpo Estriado/efectos de los fármacos , Agonistas de Dopamina/farmacología , Antagonistas de Dopamina/farmacología , Método Doble Ciego , Femenino , Pruebas Genéticas , Voluntarios Sanos , Humanos , Procesamiento de Imagen Asistido por Computador , Masculino , Mesencéfalo/diagnóstico por imagen , Mesencéfalo/efectos de los fármacos , Motivación/efectos de los fármacos , Motivación/fisiología , Oxígeno/sangre , Recompensa , Sulpirida/farmacología , Adulto Joven
6.
Glob Chang Biol ; 23(2): 881-890, 2017 02.
Artículo en Inglés | MEDLINE | ID: mdl-27310520

RESUMEN

Salt marshes can play a vital role in mitigating the effects of global environmental change by dissipating incident storm wave energy and, through accretion, tracking increasing water depths consequent upon sea level rise. Atmospheric CO2 concentrations and nutrient availability are two key variables that can affect the biological processes that contribute to marsh surface elevation gain. We measured the effects of CO2 concentrations and nutrient availability on surface elevation change in intact mixed-species blocks of UK salt marsh using six open-top chambers receiving CO2 -enriched (800 ppm) or ambient (400 ppm) air. We found more rapid surface elevation gain in elevated CO2 conditions: an average increase of 3.4 mm over the growing season relative to ambient CO2 . Boosted regression analysis to determine the relative influence of different parameters on elevation change identified that a 10% reduction in microbial activity in elevated CO2 -grown blocks had a positive influence on elevation. The biomass of Puccinellia maritima also had a positive influence on elevation, while other salt marsh species (e.g. Suaeda maritima) had no influence or a negative impact on elevation. Reduced rates of water use by the vegetation in the high CO2 treatment could be contributing to elevation gain, either directly through reduced soil shrinkage or indirectly by decreasing microbial respiration rates due to lower redox levels in the soil. Eutrophication did not influence elevation change in either CO2 treatment despite doubling aboveground biomass. The role of belowground processes (transpiration, root growth and decomposition) in the vertical adjustment of European salt marshes, which are primarily minerogenic in composition, could increase as atmospheric CO2 concentrations rise and should be considered in future wetland models for the region. Elevated CO2 conditions could enhance resilience in vulnerable systems such as those with low mineral sediment supply or where migration upwards within the tidal frame is constrained.


Asunto(s)
Eutrofización , Humedales , Biomasa , Dióxido de Carbono , Poaceae , Suelo
7.
Horm Behav ; 87: 1-7, 2017 01.
Artículo en Inglés | MEDLINE | ID: mdl-27712924

RESUMEN

Correlative evidence suggests that testosterone promotes dominance and aggression. However, causal evidence is scarce and offers mixed results. To investigate this relationship, we administered testosterone for 48h to 41 healthy young adult men in a within-subjects, double-blind placebo-controlled balanced crossover design. Subjects played the role of responders in an ultimatum game, where rejecting a low offer is costly, but serves to destroy the proposer's profit. Such action can hence be interpreted as non-physical aggression in response to social provocation. In addition, subjects completed a self-assessed mood questionnaire. As expected, self-reported aggressiveness was a key predictor of ultimatum game rejections. However, while testosterone affected subjective ratings of feeling energetic and interested, our evidence strongly suggests that testosterone had no effect on ultimatum game rejections or on aggressive mood. Our findings illustrate the importance of using causal interventions to assess correlative evidence.


Asunto(s)
Afecto/efectos de los fármacos , Agresión/efectos de los fármacos , Juegos Recreacionales/psicología , Motivación/efectos de los fármacos , Testosterona/administración & dosificación , Testosterona/efectos adversos , Adulto , Conducta Competitiva/efectos de los fármacos , Estudios Cruzados , Método Doble Ciego , Emociones/efectos de los fármacos , Humanos , Masculino , Rechazo en Psicología , Encuestas y Cuestionarios , Adulto Joven
8.
Psychiatr Rehabil J ; 47(1): 56-63, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-37917465

RESUMEN

OBJECTIVE: This study aimed to assess the feasibility of implementing Individual Placement and Support (IPS) with a focus on educational and employment goals, within a clinical service for the early detection of individuals at clinical high risk (CHR) of psychosis. METHOD: Between June 2019 and April 2021, participants were recruited and received up to 6 (± 2) months support. Primary outcome: Enrolled participants, attended sessions, and disengagement rates were analyzed to assess feasibility. SECONDARY OUTCOMES: Enrollment in mainstream education or/and employment, hours spent working or/and studying, salary, level of functioning, and self-efficacy at baseline and follow-up were compared. RESULTS: Thirty-one participants were recruited, 13 of whom were remotely recruited after the first COVID-19 lockdown. Dropout rates were relatively low (16.1%), and 26 participants (83.9%) completed the program. Each participant received on average nine sessions (M = 9.65; SD = 4.92). Secondary outcomes: At follow-up, 73.1% participants were employed, working on average more hours per week, t(25) = -2.725; p = .012, and were earning significantly more money, t(25) = -3.702; p = .001, compared to baseline. Gains in educational outcomes were less clear. Global Assessment of Functioning, t = 248.50; p = .001, and Social Occupational Functioning, t(25) = -3.273; p = .003, were significantly higher at 6-month follow-up compared to baseline. No differences were found in participants' self-efficacy. CONCLUSIONS AND IMPLICATIONS FOR PRACTICE: Findings indicate that research procedures are appropriate and that IPS implementation within a CHR clinical team is feasible. Secondary outcomes also suggest that IPS may be a beneficial intervention for young people at CHR. A longer follow-up might be needed to assess its impact on educational outcomes. (PsycInfo Database Record (c) 2024 APA, all rights reserved).


Asunto(s)
Trastornos Psicóticos , Humanos , Adolescente , Estudios de Factibilidad , Trastornos Psicóticos/epidemiología , Escolaridad , Autoeficacia , Empleo
9.
Transl Psychiatry ; 14(1): 156, 2024 Mar 21.
Artículo en Inglés | MEDLINE | ID: mdl-38509087

RESUMEN

Automatically extracted measures of speech constitute a promising marker of psychosis as disorganized speech is associated with psychotic symptoms and predictive of psychosis-onset. The potential of speech markers is, however, hampered by (i) lengthy assessments in laboratory settings and (ii) manual transcriptions. We investigated whether a short, scalable data collection (online) and processing (automated transcription) procedure would provide data of sufficient quality to extract previously validated speech measures. To evaluate the fit of our approach for purpose, we assessed speech in relation to psychotic-like experiences in the general population. Participants completed an 8-minute-long speech task online. Sample 1 included measures of psychometric schizotypy and delusional ideation (N = 446). Sample 2 included a low and high psychometric schizotypy group (N = 144). Recordings were transcribed both automatically and manually, and connectivity, semantic, and syntactic speech measures were extracted for both types of transcripts. 73%/86% participants in sample 1/2 completed the experiment. Nineteen out of 25 speech measures were strongly (r > 0.7) and significantly correlated between automated and manual transcripts in both samples. Amongst the 14 connectivity measures, 11 showed a significant relationship with delusional ideation. For the semantic and syntactic measures, On Topic score and the Frequency of personal pronouns were negatively correlated with both schizotypy and delusional ideation. Combined with demographic information, the speech markers could explain 11-14% of the variation of delusional ideation and schizotypy in Sample 1 and could discriminate between high-low schizotypy with high accuracy (0.72-0.70, AUC = 0.78-0.79) in Sample 2. The moderate to high retention rate, strong correlation of speech measures across manual and automated transcripts and sensitivity to psychotic-like experiences provides initial evidence that online collected speech in combination with automatic transcription is a feasible approach to increase accessibility and scalability of speech-based assessment of psychosis.


Asunto(s)
Trastornos Psicóticos , Trastorno de la Personalidad Esquizotípica , Humanos , Habla , Trastornos Psicóticos/complicaciones , Trastorno de la Personalidad Esquizotípica/complicaciones , Trastorno de la Personalidad Esquizotípica/diagnóstico
10.
Schizophr Bull ; 49(Suppl_2): S142-S152, 2023 03 22.
Artículo en Inglés | MEDLINE | ID: mdl-36946531

RESUMEN

BACKGROUND AND HYPOTHESIS: Mapping a patient's speech as a network has proved to be a useful way of understanding formal thought disorder in psychosis. However, to date, graph theory tools have not explicitly modelled the semantic content of speech, which is altered in psychosis. STUDY DESIGN: We developed an algorithm, "netts," to map the semantic content of speech as a network, then applied netts to construct semantic speech networks for a general population sample (N = 436), and a clinical sample comprising patients with first episode psychosis (FEP), people at clinical high risk of psychosis (CHR-P), and healthy controls (total N = 53). STUDY RESULTS: Semantic speech networks from the general population were more connected than size-matched randomized networks, with fewer and larger connected components, reflecting the nonrandom nature of speech. Networks from FEP patients were smaller than from healthy participants, for a picture description task but not a story recall task. For the former task, FEP networks were also more fragmented than those from controls; showing more connected components, which tended to include fewer nodes on average. CHR-P networks showed fragmentation values in-between FEP patients and controls. A clustering analysis suggested that semantic speech networks captured novel signals not already described by existing NLP measures. Network features were also related to negative symptom scores and scores on the Thought and Language Index, although these relationships did not survive correcting for multiple comparisons. CONCLUSIONS: Overall, these data suggest that semantic networks can enable deeper phenotyping of formal thought disorder in psychosis. Whilst here we focus on network fragmentation, the semantic speech networks created by Netts also contain other, rich information which could be extracted to shed further light on formal thought disorder. We are releasing Netts as an open Python package alongside this manuscript.


Asunto(s)
Trastornos Psicóticos , Habla , Humanos , Lenguaje , Trastornos Psicóticos/diagnóstico , Web Semántica , Semántica , Estudios de Casos y Controles
11.
R Soc Open Sci ; 10(7): 230155, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-37448479

RESUMEN

There is an urgent need to address coastal dynamics as a fundamental interaction between physical and biological processes, particularly when trying to predict future biological-physical linkages under anticipated changes in environmental forcing. More integrated modelling, support for observational networks and the use of management interventions as controlled experimental exercises should now be vigorously pursued.

12.
13.
Int J Occup Saf Ergon ; 28(4): 2293-2301, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-34583606

RESUMEN

Underground utilities pose a hazard during excavation works. One-call services are available to prevent strikes by providing relevant drawings to contractors, such as Dial Before You Dig in Australia. Even with this service and many other technologies, incidents keep occurring at an alarming rate. The research team developed a plan to observe relevant incidents occurring at multiple sites in Melbourne. Thirty cases of service strikes were detected over a 2-year period and the data showed the existence of common causes related to proactiveness in operational management. This includes errors in the use of current tools such as geographic information systems, which need to correctly show the most up-to-date buried infrastructure to be effective. This research also highlighted the need for procedures to be followed that involved having assets marked out on site and proved through non-destructive digging prior to excavation. Two practical scenarios were used to verify the research findings.


Asunto(s)
Prevención de Accidentes , Humanos , Australia
14.
Early Interv Psychiatry ; 16(6): 651-658, 2022 06.
Artículo en Inglés | MEDLINE | ID: mdl-34461672

RESUMEN

AIMS: Sleep problems are common in people with a psychosis-spectrum diagnosis and are associated with worse psychotic symptoms and lower quality of life. Sleep problems are also frequent in individuals at a clinical high risk for psychosis (CHR-P) however, less is known about the prevalence and association with symptoms in this population. This study investigates the prevalence of sleep problems within CHR-P individuals and the associations with attenuated positive symptoms, transition to psychosis, time to transition to psychosis and functioning. METHODS: The clinical records interactive search (CRIS) tool was used to carry out a retrospective study of 795 CHR-P individuals. Sleep problems, subsequent psychotic diagnoses, attenuated positive symptoms and Health of The Nation Outcome Scale scores were extracted. Regression models were used to examine the association between sleep problems and clinical outcomes. RESULTS: 59.5% of CHR-P individuals experienced sleep problems. Perceptual abnormality severity (OR = 1.24, 95% CI = 1.05-1.48) and frequency (OR = 1.31, 95% CI = 1.08-1.58) as measured by the Comprehensive Assessment of At-Risk Mental State interview, predicted sleep problems. Sleep problems were not associated with transition to psychosis; however, they were significantly associated with a shorter time to transition in individuals who developed psychosis (HR = 1.4, 95% CI = 1.05-1.88) and higher follow-up Health of the Nation Outcome Scale scores (MD = 2.26, 95% CI = 0.55-3.96). CONCLUSIONS: The high prevalence of sleep problems, along with the association with positive symptoms and worse functioning, highlights the need for effective sleep interventions in this population. Further research is needed to better understand the relationship between sleep problems and transition to psychosis.


Asunto(s)
Trastornos Psicóticos , Trastornos del Sueño-Vigilia , Adolescente , Humanos , Prevalencia , Trastornos Psicóticos/complicaciones , Trastornos Psicóticos/diagnóstico , Trastornos Psicóticos/epidemiología , Calidad de Vida , Estudios Retrospectivos , Trastornos del Sueño-Vigilia/complicaciones , Trastornos del Sueño-Vigilia/epidemiología
15.
Front Psychiatry ; 13: 945505, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36660464

RESUMEN

Introduction: Indicated primary prevention of psychosis is recommended by NICE clinical guidelines, but implementation research on Clinical High Risk for Psychosis (CHR-P) services is limited. Methods: Electronic audit of CHR-P services in England, conducted between June and September 2021, addressing core implementation domains: service configuration, detection of at-risk individuals, prognostic assessment, clinical care, clinical research, and implementation challenges, complemented by comparative analyses across service model. Descriptive statistics, Fisher's exact test and Mann-Whitney U-tests were employed. Results: Twenty-four CHR-P clinical services (19 cities) were included. Most (83.3%) services were integrated within other mental health services; only 16.7% were standalone. Across 21 services, total yearly caseload of CHR-P individuals was 693 (average: 33; range: 4-115). Most services (56.5%) accepted individuals aged 14-35; the majority (95.7%) utilized the Comprehensive Assessment of At Risk Mental States (CAARMS). About 65% of services reported some provision of NICE-compliant interventions encompassing monitoring of mental state, cognitive-behavioral therapy (CBT), and family interventions. However, only 66.5 and 4.9% of CHR-P individuals actually received CBT and family interventions, respectively. Core implementation challenges included: recruitment of specialized professionals, lack of dedicated budget, and unmet training needs. Standalone services reported fewer implementation challenges, had larger caseloads (p = 0.047) and were more likely to engage with clinical research (p = 0.037) than integrated services. Discussion: While implementation of CHR-P services is observed in several parts of England, only standalone teams appear successful at detection of at-risk individuals. Compliance with NICE-prescribed interventions is limited across CHR-P services and unmet needs emerge for national training and investments.

16.
Nat Commun ; 13(1): 3911, 2022 07 19.
Artículo en Inglés | MEDLINE | ID: mdl-35853849

RESUMEN

The influence of climate change on civil conflict and societal instability in the premodern world is a subject of much debate, in part because of the limited temporal or disciplinary scope of case studies. We present a transdisciplinary case study that combines archeological, historical, and paleoclimate datasets to explore the dynamic, shifting relationships among climate change, civil conflict, and political collapse at Mayapan, the largest Postclassic Maya capital of the Yucatán Peninsula in the thirteenth and fourteenth centuries CE. Multiple data sources indicate that civil conflict increased significantly and generalized linear modeling correlates strife in the city with drought conditions between 1400 and 1450 cal. CE. We argue that prolonged drought escalated rival factional tensions, but subsequent adaptations reveal regional-scale resiliency, ensuring that Maya political and economic structures endured until European contact in the early sixteenth century CE.


Asunto(s)
Cambio Climático , Sequías , Aclimatación , Arqueología
17.
Science ; 377(6605): 523-527, 2022 07 29.
Artículo en Inglés | MEDLINE | ID: mdl-35901146

RESUMEN

Much uncertainty exists about the vulnerability of valuable tidal marsh ecosystems to relative sea level rise. Previous assessments of resilience to sea level rise, to which marshes can adjust by sediment accretion and elevation gain, revealed contrasting results, depending on contemporary or Holocene geological data. By analyzing globally distributed contemporary data, we found that marsh sediment accretion increases in parity with sea level rise, seemingly confirming previously claimed marsh resilience. However, subsidence of the substrate shows a nonlinear increase with accretion. As a result, marsh elevation gain is constrained in relation to sea level rise, and deficits emerge that are consistent with Holocene observations of tidal marsh vulnerability.


Asunto(s)
Elevación del Nivel del Mar , Humedales , Incertidumbre
18.
PLoS One ; 16(4): e0249173, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33882056

RESUMEN

This study develops a definition of what mangrove-fisheries can encompass, incorporating a broad range of their possible characteristics. A detailed case study was conducted to develop a typology of mangrove-fishing in the Perancak Estuary, Bali, Indonesia, using interview surveys to investigate the fishing activities associated with mangroves. This case study demonstrated the complexity that a mangrove-fishery can entail, where fishing is connected to the mangrove forest by fishers of multiple sectors, functions, locations and temporal scales. Through a comparison with other mangrove-fishing communities in Bali, it also highlighted that mangrove-fisheries are variable even when in close proximity. With particular reference to this case study, a framework was developed as a flexible tool for identifying the multiple dimensions of a mangrove-fishery in a local context. Following this framework should encourage researchers and managers to look outside of the groups of fishers traditionally expected to benefit from mangrove fishing. This will enable the development of a broader definition of mangrove-fisheries in a site specific way. Identifying the full scope of fishers that contribute to or benefit from a mangrove-fishery is the first step towards building management measures that reflect the interests of groups of fishers that may otherwise remain under-represented. This is in line with international efforts for sustainability, especially in promoting small-scale fishers' access to sustainable resources under the UN Sustainable Development Goals.


Asunto(s)
Biodiversidad , Explotaciones Pesqueras/estadística & datos numéricos , Humedales , Estuarios , Explotaciones Pesqueras/economía , Humanos , Indonesia , Recursos Humanos/estadística & datos numéricos
19.
Schizophr Res ; 228: 493-501, 2021 02.
Artículo en Inglés | MEDLINE | ID: mdl-32951966

RESUMEN

BACKGROUND: Formal thought disorder is a cardinal feature of psychotic disorders, and is also evident in subtle forms before psychosis onset in individuals at clinical high-risk for psychosis (CHR-P). Assessing speech output or assessing expressive language with speech as the medium at this stage may be particularly useful in predicting later transition to psychosis. METHOD: Speech samples were acquired through administration of the Thought and Language Index (TLI) in 24 CHR-P participants, 16 people with first-episode psychosis (FEP) and 13 healthy controls. The CHR-P individuals were then followed clinically for a mean of 7 years (s.d. = 1.5) to determine if they transitioned to psychosis. Non-semantic speech graph analysis was used to assess the connectedness of transcribed speech in all groups. RESULTS: Speech was significantly more disconnected in the FEP group than in both healthy controls (p < .01) and the CHR-P group (p < .05). Results remained significant when IQ was included as a covariate. Significant correlations were found between speech connectedness measures and scores on the TLI, a manual assessment of formal thought disorder. In the CHR-P group, lower scores on two measures of speech connectedness were associated with subsequent transition to psychosis (8 transitions, 16 non-transitions; p < .05). CONCLUSION: These findings support the utility and validity of speech graph analysis methods in characterizing speech connectedness in the early phases of psychosis. This approach has the potential to be developed into an automated, objective and time-efficient way of stratifying individuals at CHR-P according to level of psychosis risk.


Asunto(s)
Trastornos Psicóticos , Habla , Humanos , Incidencia , Lenguaje , Trastornos Psicóticos/epidemiología
20.
Transl Psychiatry ; 11(1): 630, 2021 12 13.
Artículo en Inglés | MEDLINE | ID: mdl-34903724

RESUMEN

Recent work has suggested that disorganised speech might be a powerful predictor of later psychotic illness in clinical high risk subjects. To that end, several automated measures to quantify disorganisation of transcribed speech have been proposed. However, it remains unclear which measures are most strongly associated with psychosis, how different measures are related to each other and what the best strategies are to collect speech data from participants. Here, we assessed whether twelve automated Natural Language Processing markers could differentiate transcribed speech excerpts from subjects at clinical high risk for psychosis, first episode psychosis patients and healthy control subjects (total N = 54). In-line with previous work, several measures showed significant differences between groups, including semantic coherence, speech graph connectivity and a measure of whether speech was on-topic, the latter of which outperformed the related measure of tangentiality. Most NLP measures examined were only weakly related to each other, suggesting they provide complementary information. Finally, we compared the ability of transcribed speech generated using different tasks to differentiate the groups. Speech generated from picture descriptions of the Thematic Apperception Test and a story re-telling task outperformed free speech, suggesting that choice of speech generation method may be an important consideration. Overall, quantitative speech markers represent a promising direction for future clinical applications.


Asunto(s)
Procesamiento de Lenguaje Natural , Trastornos Psicóticos , Biomarcadores , Cognición , Humanos , Trastornos Psicóticos/diagnóstico , Habla
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