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1.
Sci Adv ; 9(41): eadh9513, 2023 Oct 13.
Artigo em Inglês | MEDLINE | ID: mdl-37824627

RESUMO

Antarctic climate warming and atmospheric CO2 rise during the last deglaciation may be attributed in part to sea ice reduction in the Southern Ocean. Yet, glacial-interglacial Antarctic sea ice dynamics and underlying mechanisms are poorly constrained, as robust sea ice proxy evidence is sparse. Here, we present a molecular biomarker-based sea ice record that resolves the spring/summer sea ice variability off East Antarctica during the past 40 thousand years (ka). Our results indicate that substantial sea ice reduction culminated rapidly and contemporaneously with upwelling of carbon-enriched waters in the Southern Ocean at the onset of the last deglaciation but began at least ~2 ka earlier probably driven by an increasing local integrated summer insolation. Our findings suggest that sea ice reduction and associated feedbacks facilitated stratification breakup and outgassing of CO2 in the Southern Ocean and warming in Antarctica but may also have played a leading role in initializing these deglacial processes in the Southern Hemisphere.

2.
Neurobiol Sleep Circadian Rhythms ; 15: 100100, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37484687

RESUMO

The Unified Theory suggests that sleep is a process that developed in eukaryotic animals from a relationship with an endosymbiotic bacterium. Over evolutionary time the bacterium evolved into the modern mitochondrion that continues to exert an effect on sleep patterns, e.g. the bacterium Wolbachia establishes an endosymbiotic relationship with Drosophila and many other species of insects and is able to change the host's behaviour by making it sleep. The hypothesis is supported by other host-parasite relationships, e.g., Trypanosoma brucei which causes day-time sleepiness and night-time insomnia in humans and cattle. For eukaryotes such as Monocercomonoids that don't contain mitochondria we find no evidence of them sleeping. Mitochondria produce the neurotransmitter gamma aminobutyric acid (GABA), and ornithine a precursor of the neurotransmitter GABA, together with substances such as 3,4dihydroxy phenylalanine (DOPA) a precursor for the neurotransmitter dopamine: These substances have been shown to affect the sleep/wake cycles in animals such as Drosophilia and Hydra. Eukaryote animals have traded the very positive side of having mitochondria providing aerobic respiration for them with the negative side of having to sleep. NREM (Quiet sleep) is the process endosymbionts have imposed upon their host eukaryotes and REM (Active sleep) is the push-back adaptation of eukaryotes with brains, returning to wakefulness.

3.
BMC Psychiatry ; 22(1): 817, 2022 12 21.
Artigo em Inglês | MEDLINE | ID: mdl-36544126

RESUMO

BACKGROUND: Depression is a common condition among cancer patients, across several points in the disease trajectory. Although presenting higher prevalence rates than the general population, it is often not reported or remains unnoticed. Moreover, somatic symptoms of depression are common in the oncological context and should not be dismissed as a general symptom of cancer. It becomes even more challenging to track psychological distress in the period after the treatment, where connection with the healthcare system typically becomes sporadic. The main goal of the FAITH project is to remotely identify and predict depressive symptoms in cancer survivors, based on a federated machine learning (ML) approach, towards optimization of privacy. METHODS: FAITH will remotely analyse depression markers, predicting their negative trends. These markers will be treated in distinct categories, namely nutrition, sleep, activity and voice, assessed in part through wearable technologies. The study will include 300 patients who have had a previous diagnosis of breast or lung cancer and will be recruited 1 to 5 years after the end of primary cancer. The study will be organized as a 12-month longitudinal prospective observational cohort study, with monthly assessments to evaluate depression symptoms and quality of life among cancer survivors. The primary endpoint is the severity of depressive symptoms as measured by the Hamilton Depression Rating Scale (Ham-D) at months 3, 6, 9 and 12. Secondary outcomes include self-reported anxiety and depression symptoms (HADS scale), and perceived quality of life (EORTC questionnaires), at baseline and monthly. Based on the predictive models gathered during the study, FAITH will also aim at further developing a conceptual federated learning framework, enabling to build machine learning models for the prediction and monitoring of depression without direct access to user's personal data. DISCUSSION: Improvements in the objectivity of psychiatric assessment are necessary. Wearable technologies can provide potential indicators of depression and anxiety and be used for biofeedback. If the FAITH application is effective, it will provide healthcare systems with a novel and innovative method to screen depressive symptoms in oncological settings. TRIAL REGISTRATION: Trial ID: ISRCTN10423782 . Date registered: 21/03/2022.


Assuntos
Depressão , Neoplasias , Humanos , Depressão/psicologia , Qualidade de Vida , Inteligência Artificial , Estudos Prospectivos , Ansiedade/psicologia , Resultado do Tratamento , Neoplasias/complicações , Neoplasias/terapia , Estudos Observacionais como Assunto
4.
Sensors (Basel) ; 21(14)2021 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-34300547

RESUMO

The number of people living with dementia in the world is rising at an unprecedented rate, and no country will be spared. Furthermore, neither decisive treatment nor effective medicines have yet become effective. One potential alternative to this emerging challenge is utilizing supportive technologies and services that not only assist people with dementia to do their daily activities safely and independently, but also reduce the overwhelming pressure on their caregivers. Thus, for this study, a systematic literature review is conducted in an attempt to gain an overview of the latest findings in this field of study and to address some commercially available supportive technologies and services that have potential application for people living with dementia. To this end, 30 potential supportive technologies and 15 active supportive services are identified from the literature and related websites. The technologies and services are classified into different classes and subclasses (according to their functionalities, capabilities, and features) aiming to facilitate their understanding and evaluation. The results of this work are aimed as a base for designing, integrating, developing, adapting, and customizing potential multimodal solutions for the specific needs of vulnerable people of our societies, such as those who suffer from different degrees of dementia.


Assuntos
Demência , Cuidadores , Demência/terapia , Humanos , Tecnologia
5.
Sci Rep ; 10(1): 462, 2020 01 16.
Artigo em Inglês | MEDLINE | ID: mdl-31949172

RESUMO

Submerged paloeshorelines preserved on the continental shelf indicate the depths of the most frequent (modal) low sea-levels within the glacial stages of the Late Quaternary. Here we have determined the south-east Australian shelf configuration when sea level was 40 m and 60 m below present-day sea-level (depths of the most persistent paleoshorelines within the last 120 ka), and we resolve the wave climate variations influencing the sediment transport pathways over this period. We present evidence demonstrating that the combination of shelf morphological evolution, changes in sea-level and variations in wave climate is responsible for latitudinal changes in sediment transport and deposition during the interglacial states. The paleoshoreline and shelf evolution is key to understanding the distribution of present-day shelf sand deposits and the contemporary sand budget response to future wave climate changes.

6.
Sensors (Basel) ; 18(10)2018 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-30308942

RESUMO

The Internet of Things (IoT) concept has attracted a lot of attention from the research and innovation community for a number of years already. One of the key drivers for this hype towards the IoT is its applicability to a plethora of different application domains. However, infrastructures enabling experimental assessment of IoT solutions are scarce. Being able to test and assess the behavior and the performance of any piece of technology (i.e., protocol, algorithm, application, service, etc.) under real-world circumstances is of utmost importance to increase the acceptance and reduce the time to market of these innovative developments. This paper describes the federation of eleven IoT deployments from heterogeneous application domains (e.g., smart cities, maritime, smart building, crowd-sensing, smart grid, etc.) with over 10,000 IoT devices overall which produce hundreds of thousands of observations per day. The paper summarizes the resources that are made available through a cloud-based platform. The main contributions from this paper are twofold. In the one hand, the insightful summary of the federated data resources are relevant to the experimenters that might be seeking for an experimental infrastructure to assess their innovations. On the other hand, the identification of the challenges met during the testbed integration process, as well as the mitigation strategies that have been implemented to face them, are of interest for testbed providers that can be considering to join the federation.

7.
Fungal Biol ; 117(2): 112-23, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23452949

RESUMO

Studies were conducted to determine how Phytophthora cinnamomi survives during hot and dry Mediterranean summers in areas with limited surviving susceptible hosts. Two Western Australian herbaceous perennials Chamaescilla corymbosa and Stylidium diuroides and one Western Australian annual Trachymene pilosa were collected weekly from a naturally infested site from the Eucalyptus marginata (jarrah) forest from winter to spring and less frequently during summer 2011/2012. Selfed oospores, thick-walled chlamydospores, and stromata of P. cinnamomi were observed in each species. Oospores and thick-walled chlamydospores germinated in planta confirming their viability. This is the first report of autogamy by P. cinnamomi in naturally infected plants. Stromata, reported for the first time for P. cinnamomi, were densely aggregated inside host cells, and germinated in planta with multiple germ tubes with hyphae capable of producing oospores and chlamydospores. Trachymene pilosa was completely asymptomatic, S. diuroides did not develop root lesions but some plants wilted, whilst C. corymbosa remained asymptomatic above ground but lesions developed on some tubers. The presence of haustoria suggests that P. cinnamomi grows biotrophically in some hosts. Asymptomatic, biotrophic growth of P. cinnamomi in some annual and herbaceous perennials and the production of a range of survival structures have implications for pathogen persistence over summer and its management.


Assuntos
Magnoliopsida/parasitologia , Phytophthora/crescimento & desenvolvimento , Doenças das Plantas/parasitologia , Raízes de Plantas/parasitologia , Sobrevivência Celular , Phytophthora/genética , Phytophthora/isolamento & purificação , Esporos/crescimento & desenvolvimento
8.
J Exp Bot ; 64(6): 1731-43, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23404904

RESUMO

Phosphite (H2PO⁻3) induces a range of physiological and developmental responses in plants by disturbing the homeostasis of the macronutrient phosphate. Because of its close structural resemblance to phosphate, phosphite impairs the sensing, membrane transport, and subcellular compartmentation of phosphate. In addition, phosphite induces plant defence responses by an as yet unknown mode of action. In this study, the acclimation of Arabidopsis thaliana plants to a sustained phosphite supply in the growth medium was investigated and compared with plants growing under varying phosphate supplies. Unlike phosphate, phosphite did not suppress the formation of lateral roots in several Arabidopsis accessions. In addition, the expression of well-documented phosphate-starvation-induced genes, such as miRNA399d and At4, was not repressed by phosphite accumulation, whilst the induction of PHT1;1 and PAP1 was accentuated. Thus, a mimicking of phosphate by phosphite was not observed for these classical phosphate-starvation responses. Metabolomic analysis of phosphite-treated plants showed changes in several metabolite pools, most prominently those of aspartate, asparagine, glutamate, and serine. These alterations in amino acid pools provide novel insights for the understanding of phosphite-induced pathogen resistance.


Assuntos
Aclimatação , Arabidopsis/efeitos dos fármacos , Fosfitos/farmacologia , Arabidopsis/crescimento & desenvolvimento , Arabidopsis/metabolismo , Proteínas de Arabidopsis/metabolismo , Transporte Biológico , Meios de Cultura/metabolismo , Cromatografia Gasosa-Espectrometria de Massas , Regulação da Expressão Gênica de Plantas , Metaboloma , MicroRNAs/metabolismo , Proteínas Associadas a Pancreatite , Proteínas de Transporte de Fosfato/metabolismo , Fosfatos/metabolismo , Fosfatos/farmacologia , Fosfitos/metabolismo , Raízes de Plantas/efeitos dos fármacos , Raízes de Plantas/crescimento & desenvolvimento , Brotos de Planta/efeitos dos fármacos , Brotos de Planta/metabolismo , RNA de Plantas/metabolismo , Estresse Fisiológico , Fatores de Transcrição/metabolismo
9.
Anal Biochem ; 412(1): 74-8, 2011 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-21241651

RESUMO

A sensitive fluorometric assay for the quantification of phosphite has been developed. The assay uses the enzymatic oxidation of phosphite to phosphate by a recombinant phosphite dehydrogenase with NAD(+) as cosubstrate to produce the highly fluorescent reaction product resorufin. The optimized assay can be carried out in a 96-well microtiter plate format for high-throughput screening purposes and has a detection limit of 0.25 nmol phosphite. We used the method to quantify phosphite levels in plant tissue extracts and to determine phosphite dehydrogenase activity in transgenic plants. The assay is suitable for other biological or environmental samples. Because phosphite is a widely used fungicide to protect plants from pathogenic oomycetes, the assay provides a cost-effective and easy-to-use method to monitor the fate of phosphite following application.


Assuntos
Ensaios Enzimáticos/métodos , Corantes Fluorescentes/química , Fosfitos/análise , Arabidopsis/química , NAD , NADH NADPH Oxirredutases/genética , NADH NADPH Oxirredutases/metabolismo , Oxazinas/química , Oxazinas/metabolismo , Oxirredução , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo
10.
Mol Genet Genomics ; 284(6): 425-35, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-20882389

RESUMO

Phosphite, an analog of phosphate is used to control oomycete diseases on a wide range of horticultural crops and in native ecosystems. In this study, we investigated morphological and transcriptional changes induced in Phytophthora cinnamomi by phosphite. Cytological observations revealed that phosphite caused hyphal distortions and lysis of cell walls and had an adverse effect on hyphal growth. At the molecular level, the expression levels of 43 transcripts were changed. Many of these encoded proteins involved in cell wall synthesis, or cytoskeleton functioning. The results of both the microscopic and molecular investigations are consistent with phosphite inhibiting the function of the cytoskeleton and cell wall synthesis.


Assuntos
Fosfitos/farmacologia , Phytophthora/efeitos dos fármacos , Phytophthora/genética , Sequência de Bases , Parede Celular/efeitos dos fármacos , Parede Celular/metabolismo , Citoesqueleto/efeitos dos fármacos , Citoesqueleto/metabolismo , Primers do DNA/genética , Expressão Gênica/efeitos dos fármacos , Perfilação da Expressão Gênica , Análise de Sequência com Séries de Oligonucleotídeos , Phytophthora/crescimento & desenvolvimento , Phytophthora/metabolismo , Doenças das Plantas/parasitologia , Reação em Cadeia da Polimerase Via Transcriptase Reversa
11.
Crit Rev Microbiol ; 35(3): 169-81, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19624253

RESUMO

Species of the genus Phytophthora are arguably the most destructive plant pathogens causing widespread damage to many horticultural and ornamental species, and to native ecosystems throughout the world. Globalization has increased the volume of plants being transported over long distances and has increased the spread of Phytophthora species. As traditional detection methods such as baiting or direct isolation are incapable of handling the large volume of material to be tested, researchers have developed more rapid and specific antibody and DNA based tests. This review compares the performance of the different types of tests used for detection of Phytophthora.


Assuntos
Técnicas Microbiológicas/métodos , Phytophthora/isolamento & purificação , Doenças das Plantas/microbiologia , Plantas/microbiologia , Proteínas de Algas/isolamento & purificação , DNA de Algas/isolamento & purificação , Ensaio de Imunoadsorção Enzimática/métodos , Phytophthora/química , Phytophthora/genética , Reação em Cadeia da Polimerase/métodos
13.
Fungal Genet Biol ; 35(3): 197-212, 2002 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-11929210

RESUMO

We report the development of four microsatellite loci into genetic markers for the diploid oomycete plant pathogen Phytophthora cinnamomi and that (AC)(n) and (AG)(n) microsatellites are significantly less frequent than in plant and mammal genomes. A minisatellite motif 14 bp long was also discovered. The four microsatellite loci were used to analyze sexual progeny from four separate crosses of P. cinnamomi. A large proportion of non-Mendelian inheritance was observed across all loci in all four crosses, including inheritance of more than two alleles at a locus and noninheritance of alleles from either parent at a locus. The aberrant inheritance is best explained by nondisjunction at meiosis in both the A1 parent and the A2 trisomic parents, resulting in aneuploid progeny. Two loci on the putative trisomic chromosome showed linkage and no loci were linked to mating type. One aneuploid offspring was shown to have lost alleles at two loci following subculture over 4 years, indicating that aneuploid progeny may not be mitotically stable.


Assuntos
Genes Fúngicos/genética , Genes Fúngicos Tipo Acasalamento , Repetições de Microssatélites , Phytophthora/genética , Aneuploidia , Mapeamento Cromossômico , Cruzamentos Genéticos , Primers do DNA
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