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1.
Issues Ment Health Nurs ; 45(4): 379-390, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38412433

RESUMO

Body-worn cameras are increasingly being used as a violence prevention tool in inpatient mental health wards. However, there remains a limited understanding of this technology from an implementation perspective, such as protocols and best practice guidance if cameras are to be used in these settings. This study explores the perspectives of patients, mental health staff, and senior management to understand the practical and ethical issues related to the implementation of body-worn cameras. Semi-structured interviews (n = 64) with 24 patients, 25 staff from acute wards, six Mental Health Nursing Directors, and 9 community-based patients were conducted. Interviews were analysed using reflexive thematic analysis. Ethical approval was granted by the Health Research Authority. Findings from this study show that the implementation of BWC in healthcare settings requires careful consideration. The perspectives of patients and staff demonstrate the complex reality of implementation alongside the consideration of practical and ethical issues around implementation that are essential to ensures that wards recognise the need to assess their capacity to use the cameras in a way that is fair and consistent for all involved. The findings further highlight wider questions around power and autonomy in mental health care.


Assuntos
Atenção à Saúde , Violência , Humanos , Saúde Mental , Pacientes Internados , Pesquisa Qualitativa
2.
Science ; 383(6684): 727-731, 2024 02 16.
Artigo em Inglês | MEDLINE | ID: mdl-38359106

RESUMO

The global ocean's oxygen inventory is declining in response to global warming, but the future of the low-oxygen tropics is uncertain. We report new evidence for tropical oxygenation during the Paleocene-Eocene Thermal Maximum (PETM), a warming event that serves as a geologic analog to anthropogenic warming. Foraminifera-bound nitrogen isotopes indicate that the tropical North Pacific oxygen-deficient zone contracted during the PETM. A concomitant increase in foraminifera size implies that oxygen availability rose in the shallow subsurface throughout the tropical North Pacific. These changes are consistent with ocean model simulations of warming, in which a decline in biological productivity allows tropical subsurface oxygen to rise even as global ocean oxygen declines. The tropical oxygen increase may have helped avoid a mass extinction during the PETM.

3.
J Genet Couns ; 33(1): 222-231, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37965839

RESUMO

To ensure genomic medicine is delivered safely and effectively, it is crucial that healthcare professionals are able to understand and communicate genomic results. This Education Innovation describes a nationally agreed, cross-professional competency framework outlining the knowledge, skills and behaviors required to communicate genomic results. Using principles of the nominal group technique, consensus meetings with clinical, scientific and educational experts identified six stages in the return of results process, drafted and iterated competencies. Competencies were then mapped across three levels to acknowledge different degrees of experiences and scopes of practice. The framework was open for consultation with healthcare professionals and patient communities before being published. The finalized framework includes six core competency statements required to communicate genomic results. This framework is designed to be a guide for best practice and a developmental tool to support individuals and organizations. It can be used by healthcare professionals, such as genetic counselors, to identify individual learning needs or to structure the development of training for other healthcare professionals who are increasingly involved in requesting and returning results for genomic tests.


Assuntos
Conselheiros , Genômica , Humanos , Escolaridade , Pessoal de Saúde , Conhecimento
4.
Genet Med ; 26(3): 101051, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38131308

RESUMO

PURPOSE: The UK 100,000 Genomes Project offered participants screening for additional findings (AFs) in genes associated with familial hypercholesterolemia (FH) or hereditary cancer syndromes including breast/ovarian cancer (HBOC), Lynch, familial adenomatous polyposis, MYH-associated polyposis, multiple endocrine neoplasia (MEN), and von Hippel-Lindau. Here, we report disclosure processes, manifestation of AF-related disease, outcomes, and costs. METHODS: An observational study in an area representing one-fifth of England. RESULTS: Data were collected from 89 adult AF recipients. At disclosure, among 57 recipients of a cancer-predisposition-associated AF and 32 recipients of an FH-associated AF, 35% and 88%, respectively, had personal and/or family history evidence of AF-related disease. During post-disclosure investigations, 4 cancer-AF recipients had evidence of disease, including 1 medullary thyroid cancer. Six women with an HBOC AF, 3 women with a Lynch syndrome AF, and 2 individuals with a MEN AF elected for risk-reducing surgery. New hyperlipidemia diagnoses were made in 6 FH-AF recipients and treatment (re-)initiated for 7 with prior hyperlipidemia. Generating and disclosing AFs in this region cost £1.4m; £8680 per clinically significant AF. CONCLUSION: Generation and disclosure of AFs identifies individuals with and without personal or familial evidence of disease and prompts appropriate clinical interventions. Results can inform policy toward secondary findings.


Assuntos
Neoplasias da Mama , Hiperlipidemias , Síndromes Neoplásicas Hereditárias , Adulto , Humanos , Feminino , Testes Genéticos/métodos , Revelação , Síndromes Neoplásicas Hereditárias/genética , Neoplasias da Mama/genética , Hiperlipidemias/genética , Atenção à Saúde , Predisposição Genética para Doença
5.
Int J Nurs Stud ; 140: 104456, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36821953

RESUMO

BACKGROUND: Body-worn cameras are increasingly being used as a violence prevention tool in inpatient mental health wards. However, there is a dearth of research on their use in these settings, particularly when it comes to patient perspectives. OBJECTIVE: This study aimed to explore the perspectives of patients, mental health staff, and senior management on body-worn cameras to identify the possible impacts of this technology in inpatient mental health settings. DESIGN: This was an exploratory qualitative study. SETTING: We undertook interviews online and in-person on a number of acute inpatient wards across five mental health hospitals in England. Participants were recruited in-person, online via social media, and through professional networks. PARTICIPANTS: This study recruited 24 patients from acute wards, 25 staff from acute wards, six Mental Health Nursing Directors, and nine community-based patients. METHODS: Semi-structured interviews were conducted online and in-person. Interviews were analysed using reflexive thematic analysis. Ethical approval was granted by the Health Research Authority. RESULTS: The subjective nature of how violence and aggression is defined shapes how staff and patients view the prospect of using body-worn cameras. Both staff and patients cited issues resulting from an underlying culture of mistrust in inpatient settings that leave staff and patients feeling unsafe. Body worn cameras may intensify power dynamics and undermine therapeutic relationships. Participants felt that engaging existing interventions and addressing systemic causes of violence and aggression should take priority over introducing body-worn cameras. CONCLUSIONS: There is no indication that staff or patients believe body-worn cameras will deter violence and aggression on inpatient mental health wards. They may serve as a tool for safeguarding and staff training, but there are still unexplored ethical concerns about their use and a lack of evidence to support use of this technology to deter violence in NHS mental health settings. TWEETABLE ABSTRACT: Mental health patients & staff have complex perspectives on controversial body-worn camera technology @thekeiranwilson @unafoye @maddych4dwick @gbrennancafc @cityalan.


Assuntos
Agressão , Saúde Mental , Humanos , Violência/prevenção & controle , Inglaterra , Pesquisa Qualitativa
6.
PLoS One ; 17(9): e0267636, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36155636

RESUMO

Understanding the sensitivity of species-level responses to long-term warming will become increasingly important as we look towards a warmer future. Here, we examine photosymbiont associations in planktic foraminifera at Shatsky Rise (ODP Site 1209, Pacific Ocean) across periods of global warming of differing magnitude and duration. We compare published data from the Paleocene-Eocene Thermal Maximum (PETM; ~55.9 Ma) with data from the less intense Eocene Thermal Maximum 2 (ETM2; ~54.0 Ma), and H2 events (~53.9 Ma). We use a positive relationship between test size and carbon isotope value (size-δ13C) in foraminifera shells as a proxy for photosymbiosis in Morozovella subbotinae and Acarinina soldadoensis, and find no change in photosymbiont associations during the less intense warming events, in contrast with PETM records indicating a shift in symbiosis in A. soldadoensis (but not M. subbotinae). Declines in abundance and differing preservation potential of the asymbiotic species Subbotina roesnaesensis along with sediment mixing likely account for diminished differences in δ13C between symbiotic and asymbiotic species from the PETM and ETM2. We therefore conclude that photosymbiont associations were maintained in both A. soldadoensis and M. subbotinae across ETM2 and H2. Our findings support one or both of the hypotheses that 1) changing symbiotic associations in response to warming during the PETM allowed A. soldadoensis and perhaps other acarininids to thrive through subsequent hyperthermals or 2) some critical environmental threshold value was not reached in these less intense hyperthermals.


Assuntos
Foraminíferos , Isótopos de Carbono , Aquecimento Global , Oceano Pacífico
7.
Lancet Neurol ; 21(3): 234-245, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-35182509

RESUMO

BACKGROUND: Repeat expansion disorders affect about 1 in 3000 individuals and are clinically heterogeneous diseases caused by expansions of short tandem DNA repeats. Genetic testing is often locus-specific, resulting in underdiagnosis of people who have atypical clinical presentations, especially in paediatric patients without a previous positive family history. Whole genome sequencing is increasingly used as a first-line test for other rare genetic disorders, and we aimed to assess its performance in the diagnosis of patients with neurological repeat expansion disorders. METHODS: We retrospectively assessed the diagnostic accuracy of whole genome sequencing to detect the most common repeat expansion loci associated with neurological outcomes (AR, ATN1, ATXN1, ATXN2, ATXN3, ATXN7, C9orf72, CACNA1A, DMPK, FMR1, FXN, HTT, and TBP) using samples obtained within the National Health Service in England from patients who were suspected of having neurological disorders; previous PCR test results were used as the reference standard. The clinical accuracy of whole genome sequencing to detect repeat expansions was prospectively examined in previously genetically tested and undiagnosed patients recruited in 2013-17 to the 100 000 Genomes Project in the UK, who were suspected of having a genetic neurological disorder (familial or early-onset forms of ataxia, neuropathy, spastic paraplegia, dementia, motor neuron disease, parkinsonian movement disorders, intellectual disability, or neuromuscular disorders). If a repeat expansion call was made using whole genome sequencing, PCR was used to confirm the result. FINDINGS: The diagnostic accuracy of whole genome sequencing to detect repeat expansions was evaluated against 793 PCR tests previously performed within the NHS from 404 patients. Whole genome sequencing correctly classified 215 of 221 expanded alleles and 1316 of 1321 non-expanded alleles, showing 97·3% sensitivity (95% CI 94·2-99·0) and 99·6% specificity (99·1-99·9) across the 13 disease-associated loci when compared with PCR test results. In samples from 11 631 patients in the 100 000 Genomes Project, whole genome sequencing identified 81 repeat expansions, which were also tested by PCR: 68 were confirmed as repeat expansions in the full pathogenic range, 11 were non-pathogenic intermediate expansions or premutations, and two were non-expanded repeats (16% false discovery rate). INTERPRETATION: In our study, whole genome sequencing for the detection of repeat expansions showed high sensitivity and specificity, and it led to identification of neurological repeat expansion disorders in previously undiagnosed patients. These findings support implementation of whole genome sequencing in clinical laboratories for diagnosis of patients who have a neurological presentation consistent with a repeat expansion disorder. FUNDING: Medical Research Council, Department of Health and Social Care, National Health Service England, National Institute for Health Research, and Illumina.


Assuntos
Expansão das Repetições de DNA , Medicina Estatal , Criança , Proteína do X Frágil da Deficiência Intelectual/genética , Humanos , Estudos Prospectivos , Estudos Retrospectivos , Reino Unido , Sequenciamento Completo do Genoma/métodos
8.
Am J Med Genet A ; 188(3): 959-964, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-34904380

RESUMO

Hereditary hemorrhagic telangiectasia (HHT) is an autosomal dominant multisystemic vascular dysplasia, characterized by arteriovenous malformations (AVMs), mucocutaneous telangiectasia and nosebleeds. HHT is caused by a heterozygous null allele in ACVRL1, ENG, or SMAD4, which encode proteins mediating bone morphogenetic protein (BMP) signaling. Several missense and stop-gain variants identified in GDF2 (encoding BMP9) have been reported to cause a vascular anomaly syndrome similar to HHT, however none of these patients met diagnostic criteria for HHT. HHT families from UK NHS Genomic Medicine Centres were recruited to the Genomics England 100,000 Genomes Project. Whole genome sequencing and tiering protocols identified a novel, heterozygous GDF2 sequence variant in all three affected members of one HHT family who had previously screened negative for ACVRL1, ENG, and SMAD4. All three had nosebleeds and typical HHT telangiectasia, and the proband also had severe pulmonary AVMs from childhood. In vitro studies showed the mutant construct expressed the proprotein but lacked active mature BMP9 dimer, suggesting the mutation disrupts correct cleavage of the protein. Plasma BMP9 levels in the patients were significantly lower than controls. In conclusion, we propose that this heterozygous GDF2 variant is a rare cause of HHT associated with pulmonary AVMs.


Assuntos
Malformações Arteriovenosas , Telangiectasia Hemorrágica Hereditária , Receptores de Activinas Tipo II/genética , Fístula Arteriovenosa , Malformações Arteriovenosas/diagnóstico , Malformações Arteriovenosas/genética , Criança , Endoglina/genética , Endoglina/metabolismo , Epistaxe , Fator 2 de Diferenciação de Crescimento/genética , Humanos , Mutação , Artéria Pulmonar/anormalidades , Veias Pulmonares/anormalidades , Telangiectasia Hemorrágica Hereditária/diagnóstico , Telangiectasia Hemorrágica Hereditária/genética , Telangiectasia Hemorrágica Hereditária/patologia
9.
Int J Ment Health Nurs ; 31(2): 260-277, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-34877792

RESUMO

Body-Worn-Cameras (BWCs) are being introduced into Mental Health Inpatient Units. At present, minimal evidence surrounding their use in a mental health environment exists. This review examined research on the uses of BWCs in public sector services including healthcare, public transportation, and law enforcement. All eligible studies included a visible BWC, recording on a continuous loop as the main intervention. The evidence base presented high levels of bias, highly varied camera protocols, and heterogeneity of outcome measurements. This review found there is limited evidence for the efficacy of BWCs to control and manage violence within mental health inpatient wards. The technology has shown to be effective in reducing the number of public complaints in a law enforcement setting, but it is unclear how this is achieved. It appears there may be potential beneficial uses and unintended consequences of BWCs yet to be explored by mental health services.


Assuntos
Pacientes Internados , Saúde Mental , Humanos , Aplicação da Lei/métodos , Setor Público , Violência
10.
N Engl J Med ; 385(20): 1868-1880, 2021 11 11.
Artigo em Inglês | MEDLINE | ID: mdl-34758253

RESUMO

BACKGROUND: The U.K. 100,000 Genomes Project is in the process of investigating the role of genome sequencing in patients with undiagnosed rare diseases after usual care and the alignment of this research with health care implementation in the U.K. National Health Service. Other parts of this project focus on patients with cancer and infection. METHODS: We conducted a pilot study involving 4660 participants from 2183 families, among whom 161 disorders covering a broad spectrum of rare diseases were present. We collected data on clinical features with the use of Human Phenotype Ontology terms, undertook genome sequencing, applied automated variant prioritization on the basis of applied virtual gene panels and phenotypes, and identified novel pathogenic variants through research analysis. RESULTS: Diagnostic yields varied among family structures and were highest in family trios (both parents and a proband) and families with larger pedigrees. Diagnostic yields were much higher for disorders likely to have a monogenic cause (35%) than for disorders likely to have a complex cause (11%). Diagnostic yields for intellectual disability, hearing disorders, and vision disorders ranged from 40 to 55%. We made genetic diagnoses in 25% of the probands. A total of 14% of the diagnoses were made by means of the combination of research and automated approaches, which was critical for cases in which we found etiologic noncoding, structural, and mitochondrial genome variants and coding variants poorly covered by exome sequencing. Cohortwide burden testing across 57,000 genomes enabled the discovery of three new disease genes and 19 new associations. Of the genetic diagnoses that we made, 25% had immediate ramifications for clinical decision making for the patients or their relatives. CONCLUSIONS: Our pilot study of genome sequencing in a national health care system showed an increase in diagnostic yield across a range of rare diseases. (Funded by the National Institute for Health Research and others.).


Assuntos
Genoma Humano , Doenças Raras/genética , Adolescente , Adulto , Criança , Pré-Escolar , Características da Família , Feminino , Variação Genética , Humanos , Masculino , Pessoa de Meia-Idade , Projetos Piloto , Reação em Cadeia da Polimerase , Doenças Raras/diagnóstico , Sensibilidade e Especificidade , Medicina Estatal , Reino Unido , Sequenciamento Completo do Genoma , Adulto Jovem
11.
MethodsX ; 8: 101291, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34434811

RESUMO

All studies focused on the evaluation of paleoecological variability over geological time must be linked to a specific age or time interval, which can be defined using different time scales (biostratigraphic, chronostratigraphic, geochronological or orbital). Therefore, integrated time scales are essential to allow comparisons of data from different locations and/or to assess evolutionary and other events through time. Here we use a new method to update a Paleogene magnetobiochronological time scale, with the following contributions:•The update of the Paleogene magnetobiochronological scale was made by graphical correlation with new age models and adding calcareous nannoplankton and planktonic foraminiferal biozones from different authors.•An excel file structure was proposed to plot any kind of data in MATLAB software, as long as they are associated with some of the scales shown in our updated version of Paleogene magnetobiochronology.•The excel file structure facilitates the analysis of long-term trends of taxonomic groups throughout the Paleogene, and of their evolution in a period characterized by intense climate variability.

12.
Genet Med ; 23(12): 2360-2368, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34429528

RESUMO

PURPOSE: Genome sequencing (GS) for diagnosis of rare genetic disease is being introduced into the clinic, but the complexity of the data poses challenges for developing pipelines with high diagnostic sensitivity. We evaluated the performance of the Genomics England 100,000 Genomes Project (100kGP) panel-based pipelines, using craniosynostosis as a test disease. METHODS: GS data from 114 probands with craniosynostosis and their relatives (314 samples), negative on routine genetic testing, were scrutinized by a specialized research team, and diagnoses compared with those made by 100kGP. RESULTS: Sixteen likely pathogenic/pathogenic variants were identified by 100kGP. Eighteen additional likely pathogenic/pathogenic variants were identified by the research team, indicating that for craniosynostosis, 100kGP panels had a diagnostic sensitivity of only 47%. Measures that could have augmented diagnoses were improved calling of existing panel genes (+18% sensitivity), review of updated panels (+12%), comprehensive analysis of de novo small variants (+29%), and copy-number/structural variants (+9%). Recent NHS England recommendations that partially incorporate these measures should achieve 85% overall sensitivity (+38%). CONCLUSION: GS identified likely pathogenic/pathogenic variants in 29.8% of previously undiagnosed patients with craniosynostosis. This demonstrates the value of research analysis and the importance of continually improving algorithms to maximize the potential of clinical GS.


Assuntos
Craniossinostoses , Testes Genéticos , Sequência de Bases , Mapeamento Cromossômico , Craniossinostoses/diagnóstico , Craniossinostoses/genética , Humanos , Doenças Raras/genética
13.
Am J Hum Genet ; 108(9): 1551-1557, 2021 09 02.
Artigo em Inglês | MEDLINE | ID: mdl-34329581

RESUMO

Clinical validity assessments of gene-disease associations underpin analysis and reporting in diagnostic genomics, and yet wide variability exists in practice, particularly in use of these assessments for virtual gene panel design and maintenance. Harmonization efforts are hampered by the lack of agreed terminology, agreed gene curation standards, and platforms that can be used to identify and resolve discrepancies at scale. We undertook a systematic comparison of the content of 80 virtual gene panels used in two healthcare systems by multiple diagnostic providers in the United Kingdom and Australia. The process was enabled by a shared curation platform, PanelApp, and resulted in the identification and review of 2,144 discordant gene ratings, demonstrating the utility of sharing structured gene-disease validity assessments and collaborative discordance resolution in establishing national and international consensus.


Assuntos
Consenso , Curadoria de Dados/normas , Doenças Genéticas Inatas/genética , Genômica/normas , Anotação de Sequência Molecular/normas , Austrália , Biomarcadores/metabolismo , Curadoria de Dados/métodos , Atenção à Saúde , Expressão Gênica , Ontologia Genética , Doenças Genéticas Inatas/diagnóstico , Doenças Genéticas Inatas/patologia , Genômica/métodos , Humanos , Aplicativos Móveis/provisão & distribuição , Terminologia como Assunto , Reino Unido
14.
Eur J Med Genet ; 64(7): 104213, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33930582

RESUMO

Holt-Oram syndrome (HOS) is a rare, autosomal dominant heart-hand syndrome caused by mutations in the TBX5 gene. A wide spectrum of TBX5 mutations have been reported previously, most resulting in a null allele leading to haploinsufficiency. TBX5 gene duplications have been previously reported in association with typical and atypical HOS phenotypes. Ulnar-Mammary syndrome (UMS) is a distinct rare, autosomal dominant condition caused by mutations in the TBX3 gene. TBX5 and TBX3 are physically linked in cis on human chromosome 12 and contiguous chromosome 12q24 deletions comprising both TBX5 and TBX3 genes have been previously reported but to our knowledge, duplications have never been described. We report on a large German family with at least 17 affected individuals over 6 generations bearing a duplication at 12q24.21 identified on array-CGH comprising both TBX5 and TBX3 genes. Affected patients are presenting with HOS and UMS symptoms, consisting of variable limb anomalies involving the radial and the ulnar rays and cardiac findings such as congenital heart defects, persistent arterial duct or aortic stenosis, and non-classical symptoms, such as supernumerary nipples and cardiomyopathy. Fluorescence in situ hybridisation confirmed a tandem duplication at the 12q24.21 locus. This is the first report of a contiguous TBX3/TBX5 duplication associated with HOS/UMS phenotype.


Assuntos
Anormalidades Múltiplas/genética , Doenças Mamárias/genética , Cardiopatias Congênitas/genética , Comunicação Interatrial/genética , Deformidades Congênitas das Extremidades Inferiores/genética , Fenótipo , Proteínas com Domínio T/genética , Ulna/anormalidades , Deformidades Congênitas das Extremidades Superiores/genética , Anormalidades Múltiplas/patologia , Doenças Mamárias/complicações , Doenças Mamárias/patologia , Feminino , Duplicação Gênica , Cardiopatias Congênitas/complicações , Cardiopatias Congênitas/patologia , Comunicação Interatrial/complicações , Comunicação Interatrial/patologia , Humanos , Deformidades Congênitas das Extremidades Inferiores/complicações , Deformidades Congênitas das Extremidades Inferiores/patologia , Masculino , Linhagem , Ulna/patologia , Deformidades Congênitas das Extremidades Superiores/complicações , Deformidades Congênitas das Extremidades Superiores/patologia
15.
Anal Sci Adv ; 2(5-6): 279-288, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38716159

RESUMO

In this paper, we demonstrate the suitability, sensitivity, and precision of low-cost and easy-to-use ion-selective electrodes (ISEs) for concurrent detection of NH4 + and NO3 - in soil and water by technical and non-technical end-users to enable efficient soil and water management exposed to chronic reactive nitrogen loading. We developed a simplified methodology for sample preparation followed by the demonstration of an analytical methodology resulting in improvements of sensitivity and precision of ISEs. Herein, we compared and contrasted ISEs with traditional laboratory-based technique such as Flow Injection Analysis (FIA) and portable colorimetric assay followed by comparisons of linear regression and Bayesian nonlinear calibration approaches applied on both direct potentiometry and standard addition modes of analysis in terms of in-field applications and improvement of sensitivity and precision. The ISEs were validated for sensing on a range of ambient soil and water samples representing a range of NH4 + and NO3 - concentrations from pristine to excessive saturation conditions. Herein developed methodology showed excellent agreement with lab-based and portable analytical techniques while demonstrating improvements in precision and sensitivity analysis illustrated by a decrease in confidence intervals by 50-60%. We also demonstrated the utilization of the entire ISE response curve thus removing the biases originating from linear approximation which is often currently employed. Therefore, we show that ISEs are robust yet low cost and an easy to use technology that can enable high-frequency measurement of mineral N and help to improve our understanding of N transformation processes as influenced by soil management, fertilization, land use, and climate change.

16.
Proc Natl Acad Sci U S A ; 117(41): 25302-25309, 2020 10 13.
Artigo em Inglês | MEDLINE | ID: mdl-32989142

RESUMO

Falling atmospheric CO2 levels led to cooling through the Eocene and the expansion of Antarctic ice sheets close to their modern size near the beginning of the Oligocene, a period of poorly documented climate. Here, we present a record of climate evolution across the entire Oligocene (33.9 to 23.0 Ma) based on TEX86 sea surface temperature (SST) estimates from southwestern Atlantic Deep Sea Drilling Project Site 516 (paleolatitude ∼36°S) and western equatorial Atlantic Ocean Drilling Project Site 929 (paleolatitude ∼0°), combined with a compilation of existing SST records and climate modeling. In this relatively low CO2 Oligocene world (∼300 to 700 ppm), warm climates similar to those of the late Eocene continued with only brief interruptions, while the Antarctic ice sheet waxed and waned. SSTs are spatially heterogenous, but generally support late Oligocene warming coincident with declining atmospheric CO2 This Oligocene warmth, especially at high latitudes, belies a simple relationship between climate and atmospheric CO2 and/or ocean gateways, and is only partially explained by current climate models. Although the dominant climate drivers of this enigmatic Oligocene world remain unclear, our results help fill a gap in understanding past Cenozoic climates and the way long-term climate sensitivity responded to varying background climate states.

17.
Sci Adv ; 6(28)2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32937545

RESUMO

Marine protists are integral to the structure and function of pelagic ecosystems and marine carbon cycling, with rhizarian biomass alone accounting for more than half of all mesozooplankton in the oligotrophic oceans. Yet, understanding how their environment shapes diversity within species and across taxa is limited by a paucity of observations of heritability and life history. Here, we present observations of asexual reproduction, morphologic plasticity, and ontogeny in the planktic foraminifer Neogloboquadrina pachyderma in laboratory culture. Our results demonstrate that planktic foraminifera reproduce both sexually and asexually and demonstrate extensive phenotypic plasticity in response to nonheritable factors. These two processes fundamentally explain the rapid spatial and temporal response of even imperceptibly low populations of planktic foraminifera to optimal conditions and the diversity and ubiquity of these species across the range of environmental conditions that occur in the ocean.

19.
Science ; 367(6475): 266-272, 2020 01 17.
Artigo em Inglês | MEDLINE | ID: mdl-31949074

RESUMO

The cause of the end-Cretaceous mass extinction is vigorously debated, owing to the occurrence of a very large bolide impact and flood basalt volcanism near the boundary. Disentangling their relative importance is complicated by uncertainty regarding kill mechanisms and the relative timing of volcanogenic outgassing, impact, and extinction. We used carbon cycle modeling and paleotemperature records to constrain the timing of volcanogenic outgassing. We found support for major outgassing beginning and ending distinctly before the impact, with only the impact coinciding with mass extinction and biologically amplified carbon cycle change. Our models show that these extinction-related carbon cycle changes would have allowed the ocean to absorb massive amounts of carbon dioxide, thus limiting the global warming otherwise expected from postextinction volcanism.


Assuntos
Ciclo do Carbono , Extinção Biológica , Erupções Vulcânicas , Dióxido de Carbono/análise , Aquecimento Global , México , Modelos Teóricos
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