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1.
Proc Natl Acad Sci U S A ; 121(1): e2311280120, 2024 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-38147645

RESUMO

The dominant paradigm is that large tracts of Southeast Asia's lowland rainforests were replaced with a "savanna corridor" during the cooler, more seasonal climates of the Last Glacial Maximum (LGM) (23,000 to 19,000 y ago). This interpretation has implications for understanding the resilience of Asia's tropical forests to projected climate change, implying a vulnerability to "savannization". A savanna corridor is also an important foundation for archaeological interpretations of how humans moved through and settled insular Southeast Asia and Australia. Yet an up-to-date, multiproxy, and empirical examination of the palaeoecological evidence for this corridor is lacking. We conducted qualitative and statistical analyses of 59 palaeoecological records across Southeast Asia to test the evidence for LGM savannization and clarify the relationships between methods, biogeography, and ecological change in the region from the start of Late Glacial Period (119,000 y ago) to the present. The pollen records typically show montane forest persistence during the LGM, while δ13C biomarker proxies indicate the expansion of C4-rich grasslands. We reconcile this discrepancy by hypothesizing the expansion of montane forest in the uplands and replacement of rainforest with seasonally dry tropical forest in the lowlands. We also find that smooth forest transitions between 34,000 and 2,000 y ago point to the capacity of Southeast Asia's ecosystems both to resist and recover from climate stressors, suggesting resilience to savannization. Finally, the timing of ecological change observed in our combined datasets indicates an 'early' onset of the LGM in Southeast Asia from ~30,000 y ago.


Assuntos
Ecossistema , Florestas , Humanos , Floresta Úmida , Mudança Climática , Sudeste Asiático
2.
Proc Natl Acad Sci U S A ; 118(40)2021 10 05.
Artigo em Inglês | MEDLINE | ID: mdl-34580210

RESUMO

The environmental crises currently gripping the Earth have been codified in a new proposed geological epoch: the Anthropocene. This epoch, according to the Anthropocene Working Group, began in the mid-20th century and reflects the "great acceleration" that began with industrialization in Europe [J. Zalasiewicz et al., Anthropocene 19, 55-60 (2017)]. Ironically, European ideals of protecting a pristine "wilderness," free from the damaging role of humans, is still often heralded as the antidote to this human-induced crisis [J. E. M. Watson et al., Nature, 563, 27-30 (2018)]. Despite decades of critical engagement by Indigenous and non-Indigenous observers, large international nongovernmental organizations, philanthropists, global institutions, and nation-states continue to uphold the notion of pristine landscapes as wilderness in conservation ideals and practices. In doing so, dominant global conservation policy and public perceptions still fail to recognize that Indigenous and local peoples have long valued, used, and shaped "high-value" biodiverse landscapes. Moreover, the exclusion of people from many of these places under the guise of wilderness protection has degraded their ecological condition and is hastening the demise of a number of highly valued systems. Rather than denying Indigenous and local peoples' agency, access rights, and knowledge in conserving their territories, we draw upon a series of case studies to argue that wilderness is an inappropriate and dehumanizing construct, and that Indigenous and community conservation areas must be legally recognized and supported to enable socially just, empowering, and sustainable conservation across scale.


Assuntos
Povos Indígenas/psicologia , Conhecimento , Meio Selvagem , Conservação dos Recursos Naturais , Humanos
3.
J Acad Mark Sci ; : 1-31, 2022 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-35791312

RESUMO

Resource scarcity, manifested through limited time, money or space, is a prevalent aspect of family life. Drawing on depth interviews with 30 families from diverse demographic backgrounds, this study develops a framework to demonstrate how families respond to resource scarcity. Our research examines how multi-dimensional, concurrent and/or consecutive life events, such as job changes, house moves, or childbirth, create a mismatch between available and required resources to trigger situational resource scarcity. We identify different patterns of adjustments in consumption and resource investment over time, based on families' chronic resources and reliance on support networks. Notably, the greater flexibility afforded by multiple family members is constrained by collective goals, domains of control, tensions and negotiations. Supplementary Information: The online version contains supplementary material available at 10.1007/s11747-022-00882-7.

4.
J Lesbian Stud ; 26(4): 338-353, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35980747

RESUMO

In recent decades, it has become increasingly important to reevaluate certain literature and figures in history to discover what was being communicated in the midst of, and through, the silence of minority groups. My particular focus is on the tradition of white female silence and the ways in which Anne Lister and her diaries (as separate entities) contributed to conversations about silence by establishing other methods of communication despite restrictions placed on women's voices at the time. As the main focalizers in the creation and depiction of her societal and sexual identity, I discuss Lister's "crypt hand" diaries, her self-presentation, her inheritance of Shibden Hall, and the contrast they offer between voicing and silencing. Although I argue that through these focalizers Lister does present a certain level of voicing or speaking out, ultimately this is done by using various methods of silence such as coding and implication. I also offer particular analysis of Lister's conceptualization of her own sexuality compared with that of the women she sleeps with and how her inability to fathom their queer identities contributes to a narrative of oppressive patriarchal silence.


Assuntos
Homossexualidade Feminina , Feminino , Humanos , Comunicação , Sexualidade , Grupos Minoritários , Narração
5.
J Acoust Soc Am ; 150(2): 709, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34470329

RESUMO

Much can be learned by investigating the click trains of odontocetes, including estimating the number of vocalizing animals and comparing the acoustic behavior of different individuals. Analyzing such information gathered from groups of echolocating animals in a natural environment is complicated by two main factors: overlapping echolocation produced by multiple animals at the same time, and varying levels of background noise. Starkhammar et al. [(2011a). Biol. Lett. 7(6), 836-839] described an algorithm that measures and compares the frequency spectra of individual clicks to identify groups of clicks produced by different individuals. This study presents an update to this click group separation algorithm that improves performance by comparing multiple click characteristics. There is a focus on reducing error when high background noise levels cause false click detection and recordings are of a limited frequency bandwidth, making the method applicable to a wide range of existing datasets. This method was successfully tested on recordings of free-swimming foraging dolphins with both low and high natural background noise levels. The algorithm can be adjusted via user-set parameters for application to recordings with varying sampling parameters and to species of varying click characteristics, allowing for estimates of the number of echolocating animals in free-swimming groups.


Assuntos
Golfinhos , Ecolocação , Acústica , Algoritmos , Animais , Natação
7.
Ambio ; 53(3): 470-481, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38064113

RESUMO

The Botany Wetlands are the contemporary remnant of a formerly extensive coastal freshwater wetland in the inner-urban suburbs of Sydney (Australia). This site supports a range of ecosystem services, including human physical and mental health benefits, filtration of stormwater runoff from a highly urban and industrial catchment, and accommodation space for floodwater. The wetlands also provide habitat to migratory water birds and act as a connective habitat corridor and refuge for native flora and fauna including endangered ecological communities recognised in state and national legislation. Current management strategies and 'on the ground' practices are informed by a hierarchy of laws and management plans that act to create and reinforce a specific narrative in the material landscape. Here we consider the ecological history of the wetlands, derived from paleoecological data, in the context of this complex network of governance entanglements. We argue that the system bears little resemblance to its long-term character and has been made and continually re-made by a portmanteau of inflexible regulatory structures. We suggest that maintaining ecosystem services in such a complex, hybridized sociolegal-biophysical system requires a critical view of both the power relations and physical processes that shape it.


Assuntos
Conservação dos Recursos Naturais , Ecossistema , Humanos , Áreas Alagadas , Austrália , Água Doce
8.
BMC Res Notes ; 17(1): 36, 2024 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-38268014

RESUMO

OBJECTIVE: With an increasingly ageing population and osteoarthritis prevalence, the quantification of nociceptive signals responsible for painful movements and individual responses could lead to better treatment and monitoring solutions. Changes in electrodermal activity (EDA) can be detected via changes in skin conductance (SC) and measured using finger electrodes on a wearable sensor, providing objective information for increased physiological stress response. RESULTS: To provide EDA response preliminary data, this was recorded with healthy volunteers on an array of activities while receiving a noxious stimulus. This provides a defined scenario that can be utilised as protocol feasibility testing. Raw signal extraction, processing and statistical analysis was performed using mean SC values on all participant data. The application of the stimuli resulted in a significant average increase (p < 0.05) in mean SC in four out of five activities with significant gender differences (p < 0.05) in SC and self-reported pain scores and large effect sizes. Though EDA parameters are a promising tool for nociceptive response indicators, limitations including motion artifact sensitivities and lack of previous movement-based EDA published data result in restricted analysis understanding. Refined processing pipelines with signal decomposition tools could be utilised in a protocol that quantifies nociceptive response clinically meaningfully.


Assuntos
Resposta Galvânica da Pele , Nociceptividade , Humanos , Movimento , Envelhecimento , Eletrodos
9.
Geobiology ; 22(3): e12599, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38745401

RESUMO

Studying past ecosystems from ancient environmental DNA preserved in lake sediments (sedaDNA) is a rapidly expanding field. This research has mainly involved Holocene sediments from lakes in cool climates, with little known about the suitability of sedaDNA to reconstruct substantially older ecosystems in the warm tropics. Here, we report the successful recovery of chloroplast trnL (UAA) sequences (trnL-P6 loop) from the sedimentary record of Lake Towuti (Sulawesi, Indonesia) to elucidate changes in regional tropical vegetation assemblages during the lake's Late Quaternary paleodepositional history. After the stringent removal of contaminants and sequence artifacts, taxonomic assignment of the remaining genuine trnL-P6 reads showed that native nitrogen-fixing legumes, C3 grasses, and shallow wetland vegetation (Alocasia) were most strongly associated with >1-million-year-old (>1 Ma) peats and silts (114-98.8 m composite depth; mcd), which were deposited in a landscape of active river channels, shallow lakes, and peat-swamps. A statistically significant shift toward partly submerged shoreline vegetation that was likely rooted in anoxic muddy soils (i.e., peatland forest trees and wetland C3 grasses (Oryzaceae) and nutrient-demanding aquatic herbs (presumably Oenanthe javanica)) occurred at 76 mcd (~0.8 Ma), ~0.2 Ma after the transition into a permanent lake. This wetland vegetation was most strongly associated with diatom ooze (46-37 mcd), thought to be deposited during maximum nutrient availability and primary productivity. Herbs (Brassicaceae), trees/shrubs (Fabaceae and Theaceae), and C3 grasses correlated with inorganic parameters, indicating increased drainage of ultramafic sediments and laterite soils from the lakes' catchment, particularly at times of inferred drying. Downcore variability in trnL-P6 from tropical forest trees (Toona), shady ground cover herbs (Zingiberaceae), and tree orchids (Luisia) most strongly correlated with sediments of a predominantly felsic signature considered to be originating from the catchment of the Loeha River draining into Lake Towuti during wetter climate conditions. However, the co-correlation with dry climate-adapted trees (i.e., Castanopsis or Lithocarpus) plus C4 grasses suggests that increased precipitation seasonality also contributed to the increased drainage of felsic Loeha River sediments. This multiproxy approach shows that despite elevated in situ temperatures, tropical lake sediments potentially comprise long-term archives of ancient environmental DNA for reconstructing ecosystems, which warrants further exploration.


Assuntos
DNA Antigo , Sedimentos Geológicos , Lagos , Lagos/química , Indonésia , DNA Antigo/análise , Plantas , Clima Tropical , Ecossistema , DNA de Plantas/genética
10.
Stem Cells ; 30(10): 2175-87, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22887864

RESUMO

The expression and function of several multidrug transporters (including ABCB1 and ABCG2) have been studied in human cancer cells and in mouse and human adult stem cells. However, the expression of ABCG2 in human embryonic stem cells (hESCs) remains unclear. Limited and contradictory results in the literature from two research groups have raised questions regarding its expression and function. In this study, we used quantitative real-time PCR, Northern blots, whole genome RNA sequencing, Western blots, and immunofluorescence microscopy to study ABCG2 expression in hESCs. We found that full-length ABCG2 mRNA transcripts are expressed in undifferentiated hESC lines. However, ABCG2 protein was undetectable even under embryoid body differentiation or cytotoxic drug induction. Moreover, surface ABCG2 protein was coexpressed with the differentiation marker stage-specific embryonic antigen-1 of hESCs, following constant BMP-4 signaling at days 4 and 6. This expression was tightly correlated with the downregulation of two microRNAs (miRNAs) (i.e., hsa-miR-519c and hsa-miR-520h). Transfection of miRNA mimics and inhibitors of these two miRNAs confirmed their direct involvement in the regulation ABCG2 translation. Our findings clarify the controversy regarding the expression of the ABCG2 gene and also provide new insights into translational control of the expression of membrane transporter mRNAs by miRNAs in hESCs.


Assuntos
Transportadores de Cassetes de Ligação de ATP/genética , Células-Tronco Embrionárias/metabolismo , Regulação da Expressão Gênica , MicroRNAs/genética , Proteínas de Neoplasias/genética , RNA Mensageiro/biossíntese , Membro 2 da Subfamília G de Transportadores de Cassetes de Ligação de ATP , Transportadores de Cassetes de Ligação de ATP/metabolismo , Animais , Proteína Morfogenética Óssea 4/genética , Proteína Morfogenética Óssea 4/metabolismo , Diferenciação Celular , Células Cultivadas , Células-Tronco Embrionárias/citologia , Células Alimentadoras , Fibroblastos , Humanos , Antígenos CD15/genética , Antígenos CD15/metabolismo , Camundongos , MicroRNAs/metabolismo , Proteínas de Neoplasias/metabolismo , Biossíntese de Proteínas , Transfecção
11.
Transl Perioper Pain Med ; 9(1): 416-420, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35296038

RESUMO

Congenital heart diseases (CHDs) are the most common of all congenital birth anomalies. As the survival of patients with CHDs continues to improve, this patient population is presenting for non-cardiac procedures more frequently than in the past. With ambulatory based procedures becoming increasingly common, it is critical to consider how we should best triage these patients for procedures in ambulatory settings. This paper reviews the current literature on the subject and considers strategies to guide future management.

12.
Front Rehabil Sci ; 3: 1005000, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36451804

RESUMO

The objective of this project is to produce a review of available and validated technologies suitable for gathering biomechanical and functional research data in patients with osteoarthritis (OA), outside of a traditionally fixed laboratory setting. A scoping review was conducted using defined search terms across three databases (Scopus, Ovid MEDLINE, and PEDro), and additional sources of information from grey literature were added. One author carried out an initial title and abstract review, and two authors independently completed full-text screenings. Out of the total 5,164 articles screened, 75 were included based on inclusion criteria covering a range of technologies in articles published from 2015. These were subsequently categorised by technology type, parameters measured, level of remoteness, and a separate table of commercially available systems. The results concluded that from the growing number of available and emerging technologies, there is a well-established range in use and further in development. Of particular note are the wide-ranging available inertial measurement unit systems and the breadth of technology available to record basic gait spatiotemporal measures with highly beneficial and informative functional outputs. With the majority of technologies categorised as suitable for part-remote use, the number of technologies that are usable and fully remote is rare and they usually employ smartphone software to enable this. With many systems being developed for camera-based technology, such technology is likely to increase in usability and availability as computational models are being developed with increased sensitivities to recognise patterns of movement, enabling data collection in the wider environment and reducing costs and creating a better understanding of OA patient biomechanical and functional movement data.

13.
J Bodyw Mov Ther ; 29: 60-67, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-35248290

RESUMO

BACKGROUND: Despite the lack of objective evidence, spinal manual therapies have been common practice for many years, particularly for treatment of lower back pain (LBP). This exploratory study measured and analysed the effect of a spinal mobilisation intervention on muscle tissue quality in LBP sufferers. METHODS: 40 people with LBP participated in a within-subject repeated measures cross-over study with intervention and control conditions. A myometer was used to assess the change in para-spinal muscle tissue quality before and after the intervention. Analysis considered the magnitude of muscle response together with individual covariates as potential contributors. RESULTS: A significant post-intervention reduction was observed in muscle stiffness (p = 0.012, η 2 partial = 0.15), tone (p = 0.001, η 2 partial = 0.25) and elasticity (p = 0.001, η 2 partial = 0.24). Significant increases were seen in 2 variables post-control: stiffness (p = 0.004, η 2 partial = 0.19), tone (p = 0.006, η 2 partial = 0.18) and a significant decrease in elasticity (p ˂ 0.000, η 2 partial = 0.3). Significant contributing covariates include baseline stiffness, BMI, waist circumference and sex. Baseline stiffness and tone were significantly correlated to their response levels. CONCLUSIONS: The significant reduction in all muscle tissue qualities following the intervention provide preliminary data for an evidence-based LBP therapeutic. Baseline stiffness, BMI, waist circumference and sex could act as significant contributors to magnitude of response. The results warrant further investigation into spinal mobilisation therapies to further build the objective evidence base.


Assuntos
Dor Lombar , Estudos Cross-Over , Elasticidade , Humanos , Dor Lombar/terapia , Músculos , Coluna Vertebral
14.
Behav Processes ; 200: 104691, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35750114

RESUMO

A division of labor with role specialization is defined as individuals specializing in a subtask during repetitions of a group task. While this behavior is ubiquitous among humans, there are only four candidates found among non-eusocial mammals: lions, mice, chimpanzees, and bottlenose dolphins. Bottlenose dolphins in the Cedar Keys, Florida, engage in role specialized "driver-barrier feeding", where a "driver" dolphin herds mullet towards "barrier" dolphins. Thus trapped, the mullet leap out of the water where the dolphins catch them in air. To investigate whether dolphins use acoustic cues or signals to coordinate this behavior, vocalizations were recorded before and during driver-barrier feeding. Results of fine-scale audio and video analysis during 81 events by 7 different driver individuals suggest that barrier animals coordinate movements during these events by cueing on the driver's echolocation. Analysis of dolphin whistle occurrence before driving events versus another foraging technique, which does not involve role specialization, revealed significantly higher whistle production immediately prior to driver-barrier events. Possible whistle functions include signaling motivation, recruiting individuals to participate, and/or behavioral coordination. While the use of cues and signals is common in humans completing role-specialized tasks, this is the first study to investigate the use of vocalizations in the coordination of a role-specialized behavior in a non-human mammal.


Assuntos
Golfinho Nariz-de-Garrafa , Ecolocação , Acústica , Animais , Comunicação , Humanos , Camundongos , Vocalização Animal
15.
Osteoarthr Cartil Open ; 4(1): 100236, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36474476

RESUMO

Background: Osteoarthritis is a heterogeneous condition characterised by a wide variety of factors and represents a worldwide healthcare challenge. There are multiple clinical and research specialisms involved in the diagnosis, prognosis and treatment of osteoarthritis, and there may be opportunities to share or pool data which are currently not being utilised. However, there are challenges to doing so which require carefully structured solutions and partnership working. Methods: Interviews were conducted with nine experts from various fields within osteoarthritis research. A semi-structured approach was used, and thematic analysis applied to the results. Results: Generally, osteoarthritis researchers were supportive of data sharing, provided it is done responsibly and without impacting data integrity. Benefits identified included increasing typically low-powered data, the potential for machine learning opportunities, and the potential for improved patient outcomes. However, a number of challenges were identified, relating to: data security, data harmonisation, storage costs, ethical considerations and governance. Conclusions: There is clear support for increased data sharing and partnership working in osteoarthritis research. Further investigation will be required to navigate the complex issues identified; however, it is clear that collaborative opportunities should be better facilitated and there may be innovative ways to do this. It is also clear that nomenclature within different disciplines could be better streamlined, to improve existing opportunities to harmonise data.

16.
Philos Trans R Soc Lond B Biol Sci ; 377(1849): 20200495, 2022 04 25.
Artigo em Inglês | MEDLINE | ID: mdl-35249390

RESUMO

Oceania is a key region for studying human dispersals, adaptations and interactions with other hominin populations. Although archaeological evidence now reveals occupation of the region by approximately 65-45 000 years ago, its human fossil record, which has the best potential to provide direct insights into ecological adaptations and population relationships, has remained much more elusive. Here, we apply radiocarbon dating and stable isotope approaches to the earliest human remains so far excavated on the islands of Near and Remote Oceania to explore the chronology and diets of the first preserved human individuals to step across these Pacific frontiers. We demonstrate that the oldest human (or indeed hominin) fossil outside of the mainland New Guinea-Aru area dates to approximately 11 800 years ago. Furthermore, although these early sea-faring populations have been associated with a specialized coastal adaptation, we show that Late Pleistocene-Holocene humans living on islands in the Bismarck Archipelago and in Vanuatu display a persistent reliance on interior tropical forest resources. We argue that local tropical habitats, rather than purely coasts or, later, arriving domesticates, should be emphasized in discussions of human diets and cultural practices from the onset of our species' arrival in this part of the world. This article is part of the theme issue 'Tropical forests in the deep human past'.


Assuntos
Fósseis , Hominidae , Animais , Peixes , Florestas , Humanos , Oceania , Datação Radiométrica
17.
PLoS One ; 16(6): e0252718, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34115776

RESUMO

BACKGROUND: Continuous positive airway pressure (CPAP) is the gold standard of care in providing non-invasive positive pressure support to neonates in respiratory distress in high-resource settings. While safety has been demonstrated in low-resource settings, there is a lack of knowledge on the barriers and facilitators to proper implementation. OBJECTIVE: To identify and describe the barriers, facilitators, and priorities for future implementation of CPAP for neonates and infants in low-resource settings. METHODS: A systematic search (database inception to March 6, 2020) was performed on MEDLINE, Embase, Web of Science, CINAHL, Global Health, and the WHO Global Index Medicus using PRISMA-ScR guidelines. Original research articles pertaining to implementation of CPAP devices in low-resource settings, provider or parent perspectives and experiences with CPAP, cost-benefit analyses, and cost-effectiveness studies were included. Inductive content analysis was conducted. FINDINGS: 1385 article were screened and 54 studies across 19 countries met inclusion criteria. Six major themes emerged: device attributes, patient experiences, parent experiences, provider experiences, barriers, and facilitators. Nasal trauma was the most commonly reported complication. Barriers included unreliable electricity and lack of bioengineering support. Facilitators included training, mentorship and empowerment of healthcare providers. Device design, supply chain infrastructure, and training models were imperative to the adoption and sustainability of CPAP. CONCLUSION: Sustainable implementation of CPAP in low resource settings requires easy-to-use devices, ready access to consumables, and holistic, user-driven training. Further research is necessary on standardizing metrics, interventions that support optimal provider performance, and conditions needed for successful long-term health system integration.


Assuntos
Pressão Positiva Contínua nas Vias Aéreas/métodos , Síndrome do Desconforto Respiratório do Recém-Nascido/terapia , Pressão Positiva Contínua nas Vias Aéreas/efeitos adversos , Pressão Positiva Contínua nas Vias Aéreas/economia , Pressão Positiva Contínua nas Vias Aéreas/estatística & dados numéricos , Países em Desenvolvimento , Humanos , Lactente , Recém-Nascido , Síndrome do Desconforto Respiratório do Recém-Nascido/epidemiologia
18.
Nat Ecol Evol ; 5(8): 1174-1184, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34112995

RESUMO

It has been suggested that Iberian arrival in the Americas in 1492 and subsequent dramatic depopulation led to forest regrowth that had global impacts on atmospheric CO2 concentrations and surface temperatures. Despite tropical forests representing the most important terrestrial carbon stock globally, systematic examination of historical afforestation in these habitats in the Neotropics is lacking. Additionally, there has been no assessment of similar depopulation-afforestation dynamics in other parts of the global tropics that were incorporated into the Spanish Empire. Here, we compile and semi-quantitatively analyse pollen records from the regions claimed by the Spanish in the Atlantic and Pacific to provide pan-tropical insights into European colonial impacts on forest dynamics. Our results suggest that periods of afforestation over the past millennium varied across space and time and depended on social, economic and biogeographic contexts. We argue that this reveals the unequal and divergent origins of the Anthropocene as a socio-political and biophysical process, highlighting the need for higher-resolution, targeted analyses to fully elucidate pre-colonial and colonial era human-tropical landscape interactions.


Assuntos
Florestas , Clima Tropical , América , Ásia , Ecossistema , Humanos
19.
Nat Biotechnol ; 25(7): 803-16, 2007 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-17572666

RESUMO

The International Stem Cell Initiative characterized 59 human embryonic stem cell lines from 17 laboratories worldwide. Despite diverse genotypes and different techniques used for derivation and maintenance, all lines exhibited similar expression patterns for several markers of human embryonic stem cells. They expressed the glycolipid antigens SSEA3 and SSEA4, the keratan sulfate antigens TRA-1-60, TRA-1-81, GCTM2 and GCT343, and the protein antigens CD9, Thy1 (also known as CD90), tissue-nonspecific alkaline phosphatase and class 1 HLA, as well as the strongly developmentally regulated genes NANOG, POU5F1 (formerly known as OCT4), TDGF1, DNMT3B, GABRB3 and GDF3. Nevertheless, the lines were not identical: differences in expression of several lineage markers were evident, and several imprinted genes showed generally similar allele-specific expression patterns, but some gene-dependent variation was observed. Also, some female lines expressed readily detectable levels of XIST whereas others did not. No significant contamination of the lines with mycoplasma, bacteria or cytopathic viruses was detected.


Assuntos
Células-Tronco Embrionárias/citologia , Regulação da Expressão Gênica no Desenvolvimento , Fosfatase Alcalina/metabolismo , Antígenos CD/biossíntese , Biotecnologia/métodos , Diferenciação Celular , Linhagem da Célula , Membrana Celular/metabolismo , Células Cultivadas , Análise por Conglomerados , Feminino , Perfilação da Expressão Gênica , Genótipo , Glicolipídeos/química , Humanos , Glicoproteínas de Membrana/biossíntese , Tetraspanina 29
20.
J Anal Toxicol ; 33(2): 99-103, 2009 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19239735

RESUMO

Dextromethorphan is a widely available over-the-counter antitussive that produces intoxicating, hallucinogenic, and dissociative effects at doses significantly exceeding the therapeutic range. We report the deaths of five teenage males in three incidents in three states (WA, FL, and VA) who purposefully ingested large doses of dextromethorphan for recreational purposes and died as a result of the direct toxic effects of the drug. The dextromethorphan was obtained from the same internet supplier in each case. Postmortem blood dextromethorphan concentrations ranged from 950 to 3230 ng/mL (median 1890 ng/mL). Three subjects had diphenhydramine present, one had a trace of alprazolam, and two were positive for cannabinoids. In each case, the death was attributed to dextromethorphan toxicity or toxicity from dextromethorphan and other drugs. The article discusses the metabolism, pharmacology, and potential for drug interactions for dextromethorphan and the likely mechanisms for toxicity. The dextromethorphan concentrations in all five subjects significantly exceeded the therapeutic range and are consistent with concentrations reported in other cases of dextromethorphan abuse and toxicity. The deaths resulted in the prosecution of three individuals involved in sale or distribution of the drug.


Assuntos
Dextrometorfano/sangue , Dextrometorfano/intoxicação , Internet , Marketing/métodos , Transtornos Relacionados ao Uso de Substâncias , Adolescente , Evolução Fatal , Humanos , Masculino , Marketing/legislação & jurisprudência , Intoxicação/sangue , Transtornos Relacionados ao Uso de Substâncias/sangue , Adulto Jovem
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