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1.
Proc Natl Acad Sci U S A ; 121(7): e2311703121, 2024 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-38315863

RESUMO

Global polls have shown that people in high-income countries generally report being more satisfied with their lives than people in low-income countries. The persistence of this correlation, and its similarity to correlations between income and life satisfaction within countries, could lead to the impression that high levels of life satisfaction can only be achieved in wealthy societies. However, global polls have typically overlooked small-scale, nonindustrialized societies, which can provide an alternative test of the consistency of this relationship. Here, we present results from a survey of 2,966 members of Indigenous Peoples and local communities among 19 globally distributed sites. We find that high average levels of life satisfaction, comparable to those of wealthy countries, are reported for numerous populations that have very low monetary incomes. Our results are consistent with the notion that human societies can support very satisfying lives for their members without necessarily requiring high degrees of monetary wealth.


Assuntos
Renda , Satisfação Pessoal , Humanos , Pobreza , Sociedades , Problemas Sociais
2.
Proc Natl Acad Sci U S A ; 120(25): e2219564120, 2023 06 20.
Artigo em Inglês | MEDLINE | ID: mdl-37307470

RESUMO

The daily activities of ≈8 billion people occupy exactly 24 h per day, placing a strict physical limit on what changes can be achieved in the world. These activities form the basis of human behavior, and because of the global integration of societies and economies, many of these activities interact across national borders. Yet, there is no comprehensive overview of how the finite resource of time is allocated at the global scale. Here, we estimate how all humans spend their time using a generalized, physical outcome-based categorization that facilitates the integration of data from hundreds of diverse datasets. Our compilation shows that most waking hours are spent on activities intended to achieve direct outcomes for human minds and bodies (9.4 h/d), while 3.4 h/d are spent modifying our inhabited environments and the world beyond. The remaining 2.1 h/d are devoted to organizing social processes and transportation. We distinguish activities that vary strongly with GDP per capita, including the time allocated to food provision and infrastructure, vs. those that do not vary consistently, such as meals and transportation time. Globally, the time spent directly extracting materials and energy from the Earth system is small, on the order of 5 min per average human day, while the time directly dealing with waste is on the order of 1 min per day, suggesting a large potential scope to modify the allocation of time to these activities. Our results provide a baseline quantification of the temporal composition of global human life that can be expanded and applied to multiple fields of research.


Assuntos
Planeta Terra , Cabeça , Humanos , Refeições , Registros , Meios de Transporte
3.
Proc Natl Acad Sci U S A ; 117(4): 1941-1950, 2020 01 28.
Artigo em Inglês | MEDLINE | ID: mdl-31937662

RESUMO

We present a global time series of street-network sprawl-that is, sprawl as measured through the local connectivity of the street network. Using high-resolution data from OpenStreetMap and a satellite-derived time series of urbanization, we compute and validate changes over time in multidimensional street connectivity measures based on graph-theoretic and geographic concepts. We report on global, national, and city-level trends since 1975 in the street-network disconnectedness index (SNDi), based on every mapped node and edge in the world. Streets in new developments in 90% of the 134 most populous countries have become less connected since 1975, while just 29% show an improving trend since 2000. The same period saw a near doubling in the relative frequency of a street-network type characterized by high circuity, typical of gated communities. We identify persistence in street-network sprawl, indicative of path-dependent processes. Specifically, cities and countries with low connectivity in recent years also had relatively low preexisting connectivity in our earliest time period. We discuss implications for policy intervention in road building in new and expanding cities as a top priority for sustainable urban development.

4.
Environ Sci Technol ; 56(12): 8308-8318, 2022 06 21.
Artigo em Inglês | MEDLINE | ID: mdl-35675631

RESUMO

The Chinese government implemented a national household energy transition program that replaced residential coal heating stoves with electricity-powered heat pumps for space heating in northern China. As part of a baseline assessment of the program, this study investigated variability in personal air pollution exposures within villages and between villages and evaluated exposure patterns by sociodemographic factors. We randomly recruited 446 participants in 50 villages in four districts in rural Beijing and measured 24 h personal exposures to fine particulate matter (PM2.5) and black carbon (BC). The geometric mean personal exposure to PM2.5 and BC was 72 and 2.5 µg/m3, respectively. The variability in PM2.5 and BC exposures was greater within villages than between villages. Study participants who used traditional stoves as their dominant source of space heating were exposed to the highest levels of PM2.5 and BC. Wealthier households tended to burn more coal for space heating, whereas less wealthy households used more biomass. PM2.5 and BC exposures were almost uniformly distributed by socioeconomic status. Future work that combines these results with PM2.5 chemical composition analysis will shed light on whether air pollution source contributors (e.g., industrial, traffic, and household solid fuel burning) follow similar distributions.


Assuntos
Poluentes Atmosféricos , Poluição do Ar em Ambientes Fechados , Poluição do Ar , Poluentes Atmosféricos/análise , Poluição do Ar/análise , Poluição do Ar em Ambientes Fechados/análise , Pequim , China , Carvão Mineral , Culinária , Exposição Ambiental/análise , Características da Família , Humanos , Material Particulado/análise , População Rural , Fuligem/análise
5.
Indoor Air ; 32(8): e13095, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-36040277

RESUMO

The coronavirus (COVID-19) lockdown in China is thought to have reduced air pollution emissions due to reduced human mobility and economic activities. Few studies have assessed the impacts of COVID-19 on community and indoor air quality in environments with diverse socioeconomic and household energy use patterns. The main goal of this study was to evaluate whether indoor and community air pollution differed before, during, and after the COVID-19 lockdown in homes with different energy use patterns. Using calibrated real-time PM2.5 sensors, we measured indoor and community air quality in 147 homes from 30 villages in Beijing over 4 months including periods before, during, and after the COVID-19 lockdown. Community pollution was higher during the lockdown (61 ± 47 µg/m3 ) compared with before (45 ± 35 µg/m3 , p < 0.001) and after (47 ± 37 µg/m3 , p < 0.001) the lockdown. However, we did not observe significantly increased indoor PM2.5 during the COVID-19 lockdown. Indoor-generated PM2.5 in homes using clean energy for heating without smokers was the lowest compared with those using solid fuel with/without smokers, implying air pollutant emissions are reduced in homes using clean energy. Indoor air quality may not have been impacted by the COVID-19 lockdown in rural settings in China and appeared to be more impacted by the household energy choice and indoor smoking than the COVID-19 lockdown. As clean energy transitions occurred in rural households in northern China, our work highlights the importance of understanding multiple possible indoor sources to interpret the impacts of interventions, intended or otherwise.


Assuntos
Poluentes Atmosféricos , Poluição do Ar em Ambientes Fechados , Poluição do Ar , COVID-19 , Poluentes Atmosféricos/análise , Poluição do Ar/análise , Poluição do Ar em Ambientes Fechados/análise , Pequim/epidemiologia , China/epidemiologia , Controle de Doenças Transmissíveis , Monitoramento Ambiental , Humanos , Material Particulado/análise
6.
Proc Natl Acad Sci U S A ; 112(27): 8244-9, 2015 07 07.
Artigo em Inglês | MEDLINE | ID: mdl-26080422

RESUMO

The urban street network is one of the most permanent features of cities. Once laid down, the pattern of streets determines urban form and the level of sprawl for decades to come. We present a high-resolution time series of urban sprawl, as measured through street network connectivity, in the United States from 1920 to 2012. Sprawl started well before private car ownership was dominant and grew steadily until the mid-1990s. Over the last two decades, however, new streets have become significantly more connected and grid-like; the peak in street-network sprawl in the United States occurred in ∼ 1994. By one measure of connectivity, the mean nodal degree of intersections, sprawl fell by ∼ 9% between 1994 and 2012. We analyze spatial variation in these changes and demonstrate the persistence of sprawl. Places that were built with a low-connectivity street network tend to stay that way, even as the network expands. We also find suggestive evidence that local government policies impact sprawl, as the largest increases in connectivity have occurred in places with policies to promote gridded streets and similar New Urbanist design principles. We provide for public use a county-level version of our street-network sprawl dataset comprising a time series of nearly 100 y.


Assuntos
Planejamento de Cidades/estatística & dados numéricos , Planejamento Ambiental/estatística & dados numéricos , Meios de Transporte/estatística & dados numéricos , Reforma Urbana/estatística & dados numéricos , Cidades , Planejamento de Cidades/legislação & jurisprudência , Planejamento de Cidades/tendências , Simulação por Computador , Planejamento Ambiental/legislação & jurisprudência , Planejamento Ambiental/tendências , Previsões , Geografia , Regulamentação Governamental , Humanos , Modelos Teóricos , Fatores de Tempo , Estados Unidos , Reforma Urbana/legislação & jurisprudência , Reforma Urbana/tendências
7.
J Exp Biol ; 218(Pt 11): 1767-76, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25908057

RESUMO

The heart and left ventricle of the marsupial western grey kangaroo Macropus fuliginosus exhibit biphasic allometric growth, whereby a negative shift in the trajectory of cardiac growth occurs at pouch exit. In this study, we used transmission electron microscopy to examine the scaling of left ventricle cardiomyocyte ultrastructure across development in the western grey kangaroo over a 190-fold body mass range (0.355-67.5 kg). The volume-density (%) of myofibrils, mitochondria, sarcoplasmic reticuli and T-tubules increase significantly during in-pouch growth, such that the absolute volume (ml) of these organelles scales with body mass (Mb; kg) with steep hyperallometry: 1.41Mb (1.38), 0.64Mb (1.29), 0.066Mb (1.45) and 0.035Mb (1.87), respectively. Maturation of the left ventricle ultrastructure coincides with pouch vacation, as organelle volume-densities scale independent of body mass across post-pouch development, such that absolute organelle volumes scale in parallel and with relatively shallow hypoallometry: 4.65Mb (0.79), 1.75Mb (0.77), 0.21Mb (0.79) and 0.35Mb (0.79), respectively. The steep hyperallometry of organelle volumes and volume-densities across in-pouch growth is consistent with the improved contractile performance of isolated cardiac muscle during fetal development in placental mammals, and is probably critical in augmenting cardiac output to levels necessary for endothermy and independent locomotion in the young kangaroo as it prepares for pouch exit. The shallow hypoallometry of organelle volumes during post-pouch growth suggests a decrease in relative cardiac requirements as body mass increases in free-roaming kangaroos, which is possibly because the energy required for hopping is independent of speed, and the capacity for energy storage during hopping could increase as the kangaroo grows.


Assuntos
Macropodidae/anatomia & histologia , Miócitos Cardíacos/ultraestrutura , Retículo Sarcoplasmático/ultraestrutura , Animais , Peso Corporal , Ventrículos do Coração/crescimento & desenvolvimento , Ventrículos do Coração/ultraestrutura , Macropodidae/crescimento & desenvolvimento , Mitocôndrias/ultraestrutura , Miofibrilas/ultraestrutura , Remodelação Ventricular
8.
bioRxiv ; 2023 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-36945541

RESUMO

Bacteroides, the prominent bacteria in the human gut, play a crucial role in degrading complex polysaccharides. Their abundance is influenced by phages belonging to the Crassvirales order. Despite identifying over 600 Crassvirales genomes computationally, only few have been successfully isolated. Continued efforts in isolation of more Crassvirales genomes can provide insights into phage-host-evolution and infection mechanisms. We focused on wastewater samples, as potential sources of phages infecting various Bacteroides hosts. Sequencing, assembly, and characterization of isolated phages revealed 14 complete genomes belonging to three novel Crassvirales species infecting Bacteroides cellulosilyticus WH2. These species, Kehishuvirus sp. 'tikkala' strain Bc01, Kolpuevirus sp. 'frurule' strain Bc03, and 'Rudgehvirus jaberico' strain Bc11, spanned two families, and three genera, displaying a broad range of virion productions. Upon testing all successfully cultured Crassvirales species and their respective bacterial hosts, we discovered that they do not exhibit co-evolutionary patterns with their bacterial hosts. Furthermore, we observed variations in gene similarity, with greater shared similarity observed within genera. However, despite belonging to different genera, the three novel species shared a unique structural gene that encodes the tail spike protein. When investigating the relationship between this gene and host interaction, we discovered evidence of purifying selection, indicating its functional importance. Moreover, our analysis demonstrated that this tail spike protein binds to the TonB-dependent receptors present on the bacterial host surface. Combining these observations, our findings provide insights into phage-host interactions and present three Crassvirales species as an ideal system for controlled infectivity experiments on one of the most dominant members of the human enteric virome. Impact statement: Bacteriophages play a crucial role in shaping microbial communities within the human gut. Among the most dominant bacteriophages in the human gut microbiome are Crassvirales phages, which infect Bacteroides. Despite being widely distributed, only a few Crassvirales genomes have been isolated, leading to a limited understanding of their biology, ecology, and evolution. This study isolated and characterized three novel Crassvirales genomes belonging to two different families, and three genera, but infecting one bacterial host, Bacteroides cellulosilyticus WH2. Notably, the observation confirmed the phages are not co-evolving with their bacterial hosts, rather have a shared ability to exploit similar features in their bacterial host. Additionally, the identification of a critical viral protein undergoing purifying selection and interacting with the bacterial receptors opens doors to targeted therapies against bacterial infections. Given Bacteroides role in polysaccharide degradation in the human gut, our findings advance our understanding of the phage-host interactions and could have important implications for the development of phage-based therapies. These discoveries may hold implications for improving gut health and metabolism to support overall well-being. Data summary: The genomes used in this research are available on Sequence Read Archive (SRA) within the project, PRJNA737576. Bacteroides cellulosilyticus WH2, Kehishuvirus sp. 'tikkala' strain Bc01, Kolpuevirus sp. ' frurule' strain Bc03, and 'Rudgehvirus jaberico' strain Bc11 are all available on GenBank with accessions NZ_CP072251.1 ( B. cellulosilyticus WH2), QQ198717 (Bc01), QQ198718 (Bc03), and QQ198719 (Bc11), and we are working on making the strains available through ATCC. The 3D protein structures for the three Crassvirales genomes are available to download at doi.org/10.25451/flinders.21946034.

9.
Microb Genom ; 9(9)2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37665209

RESUMO

Bacteroides, the prominent bacteria in the human gut, play a crucial role in degrading complex polysaccharides. Their abundance is influenced by phages belonging to the Crassvirales order. Despite identifying over 600 Crassvirales genomes computationally, only few have been successfully isolated. Continued efforts in isolation of more Crassvirales genomes can provide insights into phage-host-evolution and infection mechanisms. We focused on wastewater samples, as potential sources of phages infecting various Bacteroides hosts. Sequencing, assembly, and characterization of isolated phages revealed 14 complete genomes belonging to three novel Crassvirales species infecting Bacteroides cellulosilyticus WH2. These species, Kehishuvirus sp. 'tikkala' strain Bc01, Kolpuevirus sp. 'frurule' strain Bc03, and 'Rudgehvirus jaberico' strain Bc11, spanned two families, and three genera, displaying a broad range of virion productions. Upon testing all successfully cultured Crassvirales species and their respective bacterial hosts, we discovered that they do not exhibit co-evolutionary patterns with their bacterial hosts. Furthermore, we observed variations in gene similarity, with greater shared similarity observed within genera. However, despite belonging to different genera, the three novel species shared a unique structural gene that encodes the tail spike protein. When investigating the relationship between this gene and host interaction, we discovered evidence of purifying selection, indicating its functional importance. Moreover, our analysis demonstrated that this tail spike protein binds to the TonB-dependent receptors present on the bacterial host surface. Combining these observations, our findings provide insights into phage-host interactions and present three Crassvirales species as an ideal system for controlled infectivity experiments on one of the most dominant members of the human enteric virome.


Assuntos
Bacteriófagos , Glicoproteína da Espícula de Coronavírus , Humanos , Bactérias , Bacteriófagos/genética , Bacteroides/genética
10.
PLoS One ; 17(7): e0270583, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35834510

RESUMO

Time use studies quantify what people do, over particular time intervals. The results of these studies have illuminated diverse and important aspects of societies and economies, from populations around the world. Yet, these efforts have advanced in a fragmented manner, using non-standardized descriptions (lexicons) of time use that often require researchers to make arbitrary designations among non-exclusive categories, and are not easily translated between disciplines. Here we propose a new approach, assembling multiple dimensions of time use to construct what we call the human chronome, as a means to provide novel interdisciplinary perspectives on fundamental aspects of human behaviour and experience. The approach is enabled by parallel lexicons, each of which aims for low ambiguity by focusing on a single coherent categorical dimension, and which can then be combined to provide a multi-dimensional characterization. Each lexicon should follow a single, consistent theoretical orientation, ensure exhaustiveness and exclusivity, and minimize ambiguity arising from temporal and social aggregation. As a pragmatic first step towards this goal, we describe the development of the Motivating- Outcome- Oriented General Activity Lexicon (MOOGAL). The MOOGAL is theoretically oriented towards the outcomes of activities, is applicable to any human from hunter-gatherers to modern urbanites, and deliberately focuses on the physical outcomes which motivate the undertaking of activities to reduce ambiguity from social aggregation. We illustrate the utility of the MOOGAL by comparing it with existing economic, sociological and anthropological lexicons, showing that it exhaustively covers the previously-defined activities with low ambiguity, and apply it to time use and economic data from two countries. Our results support the feasibility of using generalized lexicons to incorporate diverse observational constraints on time use, thereby providing a rich interdisciplinary perspective on the human system that is particularly relevant to the current period of rapid social, technological and environmental change.


Assuntos
Estudos Interdisciplinares , Motivação , Humanos
11.
SN Soc Sci ; 1(7): 176, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34723202

RESUMO

The growing maturity of the "science of happiness" raises the prospect of enabling government policy to be more accountable to the measurable subjective experience of the population. In its ideal form, the application of this science promises to inform decision makers about the likely distribution of life satisfaction resulting from any prospective policy, allowing for the selection of more optimal policy. Such "budgeting for wellbeing" invites three natural objections, beyond normative quibbles with the subjective objective: (1) non-incremental changes are unlikely in large bureaucracies, so a new accounting system for devising and costing government policies and budgets is too radical, (2) governments do not have an authoritative set of credible cost/benefit coefficients to use in analysis, and (3) long-run objectives, risks, and environmental considerations cannot be feasibly captured in quantitative projections of human subjective wellbeing. Three institutions are needed to address these challenges. I describe (a) an evolving collection of largely objective indicators for monitoring progress, with life satisfaction providing quantitative structure and overarching visibility to the system, (b) a publicly curated, evidence-based Database of Happiness Coefficients, and (c) independent public agencies that decide on a growing list of material constraints on the economy. Rather than overwhelmingly novel, these features have antecedents and analogues. Moreover, most civil service decision-making and projection-making apparatuses need not change. Also, there will be no less room nor less need for political debate and platforms. While shifting society to human-centred measures of progress may be radically transformative in the long run, it can be initiated smoothly and non-disruptively.

12.
PLoS One ; 16(1): e0244569, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33439863

RESUMO

Economic growth is often assumed to improve happiness for people in low income countries, although the association between monetary income and subjective well-being has been a subject of debate. We test this assumption by comparing three different measures of subjective well-being in very low-income communities with different levels of monetization. Contrary to expectations, all three measures of subjective well-being were very high in the least-monetized sites and comparable to those found among citizens of wealthy nations. The reported drivers of happiness shifted with increasing monetization: from enjoying experiential activities in contact with nature at the less monetized sites, to social and economic factors at the more monetized sites. Our results suggest that high levels of subjective well-being can be achieved with minimal monetization, challenging the perception that economic growth will raise life satisfaction among low income populations.


Assuntos
Felicidade , Satisfação Pessoal , Adulto , Desenvolvimento Econômico , Feminino , Humanos , Renda , Masculino , Pessoa de Meia-Idade , Fatores Socioeconômicos
13.
Reprod Fertil Dev ; 21(3): 428-39, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19261220

RESUMO

The Australian murine rodent, the plains mouse (Pseudomys australis), possesses a highly complex sperm head, in which there are, in addition to an apical hook, two ventral processes that extend from its upper concave surface. The present study set out to determine the temporal deposition and distribution of the proteins within these structures during late spermiogenesis by light and electron microscopy using various antibodies to bull and laboratory rat sperm-head cytoskeletal proteins. The findings show that there are two phases of protein deposition. In the first phase, perinuclear theca proteins are deposited at the base of the ventral processes around the acrosomal extensions of the developing spermatids. In the second phase, as the ventral processes expand, actin and then perforatorial proteins are laid down during which time the processes become progressively more bilaterally flattened. These various proteins are moulded together to give rise to the two very large cytoskeletal structures that extend from the upper concave surface of the sperm head. They may be involved in binding the spermatozoon to the outer surface of the zona pellucida and/or in aiding the spermatozoon in zona penetration at the time of fertilisation.


Assuntos
Proteínas do Citoesqueleto/análise , Murinae , Cabeça do Espermatozoide/química , Acrossomo/química , Actinas/análise , Animais , Austrália , Núcleo Celular/química , Eletroforese em Gel de Poliacrilamida , Imuno-Histoquímica , Masculino , Microscopia Eletrônica , Cabeça do Espermatozoide/ultraestrutura , Espermátides/química , Espermátides/ultraestrutura , Espermatogênese , Testículo/química , Testículo/ultraestrutura , Fatores de Tempo
14.
Nat Commun ; 10(1): 161, 2019 01 11.
Artigo em Inglês | MEDLINE | ID: mdl-30635565

RESUMO

Subjective well-being surveys show large and consistent variation among countries, much of which can be predicted from a small number of social and economic proxy variables. But the degree to which these life evaluations might feasibly change over coming decades, at the global scale, has not previously been estimated. Here, we use observed historical trends in the proxy variables to constrain feasible future projections of self-reported life evaluations to the year 2050. We find that projected effects of macroeconomic variables tend to lead to modest improvements of global average life evaluations. In contrast, scenarios based on non-material variables project future global average life evaluations covering a much wider range, lying anywhere from the top 15% to the bottom 25% of present-day countries. These results highlight the critical role of non-material factors such as social supports, freedoms, and fairness in determining the future of human well-being.


Assuntos
Saúde Global/tendências , Qualidade de Vida , Fatores Sociológicos , Previsões , Humanos , Organização para a Cooperação e Desenvolvimento Econômico
15.
PLoS One ; 14(11): e0223078, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31770386

RESUMO

Disconnected urban street networks, which we call "street-network sprawl," are strongly associated with increased vehicle travel, energy use and CO2 emissions, as shown by previous research in Europe and North America. In this paper, we provide the first systematic and globally commensurable measures of street-network sprawl based on graph-theoretic and geographic concepts. Using data on all 46 million km of mapped streets worldwide, we compute these measures for the entire Earth at the highest possible resolution. We generate a summary scalar measure for street-network sprawl, the Street-Network Disconnectedness index (SNDi), as well as a data-driven multidimensional classification that identifies eight empirical street-network types that span the spectrum of connectivity, from gridiron to dendritic (tree-like) and circuitous networks. Our qualitative validation shows that both the scalar and multidimensional measures are meaningfully comparable within and across countries, and successfully capture varied dimensions of walkability and urban development. We further show that in select high-income countries, our measures explain cross-sectional variation in household transportation decisions, and a one standard-deviation increase in SNDi is associated with an extra 0.25 standard deviations in cars owned per household. We aggregate our measures to the scale of countries, cities, and smaller geographies and describe patterns in street-network sprawl around the world. Latin America, Japan, South Korea, much of Europe, and North Africa stand out for their low levels of street-network sprawl, while the highest levels are found in south-east Asia, the United States, and the British Isles. Our calculations provide the foundation for future work to understand urban processes, predict future pathways of transportation energy consumption and emissions, and identify effective policy responses.


Assuntos
Mapas como Assunto , Meios de Transporte , Cidades , Humanos , Renda , Internacionalidade , População , Planejamento Social , Análise Espacial
16.
PLoS One ; 14(10): e0224742, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31661515

RESUMO

[This corrects the article DOI: 10.1371/journal.pone.0180698.].

17.
PLoS One ; 14(1): e0210091, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30673727

RESUMO

This paper presents a new public-use dataset for community-level life satisfaction in Canada, based on more than 500,000 observations from the Canadian Community Health Surveys and the General Social Surveys. The country is divided into 1216 similarly sampled geographic regions, using natural, built, and administrative boundaries. A cross-validation exercise suggests that our choice of minimum sampling thresholds approximately maximizes the predictive power of our estimates. The resulting dataset reveals robust differences in life satisfaction between and across urban and rural communities. We compare aggregated life satisfaction data with a range of key census variables to illustrate some of the ways in which lives differ in the most and least happy communities.


Assuntos
Felicidade , Inquéritos Epidemiológicos/estatística & dados numéricos , Satisfação Pessoal , Características de Residência/estatística & dados numéricos , Inquéritos e Questionários/estatística & dados numéricos , Canadá , Humanos , População Rural/estatística & dados numéricos , Fatores Socioeconômicos , População Urbana/estatística & dados numéricos
18.
Case Rep Transplant ; 2018: 3264921, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29854547

RESUMO

Neutropenic enterocolitis (NE) historically primarily affects pediatric patients with leukemia who are undergoing chemotherapy or who have recently received bone marrow transplants. Although a few case reports have shown NE occurring outside of this typical population, to our knowledge, this is the first published case of NE occurring in the setting of pediatric heart transplant. This patient was diagnosed several months after pediatric heart transplant, with radiographs showing evidence of pneumatosis intestinalis. Although NE does not typically affect solid organ transplant patients, this patient had a variety of risk factors that may have predisposed her to development of NE such as severe neutropenia, supratherapeutic tacrolimus level, immunosuppression with cytotoxic agents, and elevated Epstein-Barr viral load. Fortunately, this patient improved with bowel rest, fluids, antibiotics, and alteration of her immunosuppressive regimen. However, NE can be fatal, and thus it is an important condition to consider, even in patients without leukemia or on chemotherapeutic regimens.

19.
J Morphol ; 268(8): 683-9, 2007 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-17492780

RESUMO

The structural organization of the spermatozoon from the Eurasian beaver, Castor fiber (Family: Castoridae), was determined and compared to that of other sciuromorph rodents. The beaver spermatozoon has a head, which is variable in form but usually paddle-shaped, with a small nucleus and very large acrosome, and a tail that is relatively short compared to that of most other rodents. Transmission electron microscopy indicates that in most testicular spermatozoa the acrosome projects apically, although in a few it becomes partly flexed. During the final stages of maturation, however, the acrosome becomes highly folded so that the apical segment comes to lie alongside part of the acrosome that occurs lateral to the nucleus, with, in some cases, fusion taking place between the outer acrosomal membranes. The sperm nucleus is wedge-shaped, being broader basally and narrowing apically with an occasional large nuclear vacuole occurring. This spermatozoon structure is markedly different from that found in the other species of Geomyoidea, which is the sister group of the Castoridae. The findings thus emphasize the highly divergent nature of the beaver spermatozoon and demonstrate that, within the proposed Infraorder Castorimorpha, very large differences in sperm structure have evolved.


Assuntos
Roedores/anatomia & histologia , Cabeça do Espermatozoide/ultraestrutura , Cauda do Espermatozoide/ultraestrutura , Animais , Ásia , Evolução Biológica , Europa (Continente) , Masculino , Microscopia Eletrônica de Varredura , Microscopia Eletrônica de Transmissão , Especificidade da Espécie
20.
PLoS One ; 12(8): e0180698, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28797037

RESUMO

OpenStreetMap, a crowdsourced geographic database, provides the only global-level, openly licensed source of geospatial road data, and the only national-level source in many countries. However, researchers, policy makers, and citizens who want to make use of OpenStreetMap (OSM) have little information about whether it can be relied upon in a particular geographic setting. In this paper, we use two complementary, independent methods to assess the completeness of OSM road data in each country in the world. First, we undertake a visual assessment of OSM data against satellite imagery, which provides the input for estimates based on a multilevel regression and poststratification model. Second, we fit sigmoid curves to the cumulative length of contributions, and use them to estimate the saturation level for each country. Both techniques may have more general use for assessing the development and saturation of crowd-sourced data. Our results show that in many places, researchers and policymakers can rely on the completeness of OSM, or will soon be able to do so. We find (i) that globally, OSM is ∼83% complete, and more than 40% of countries-including several in the developing world-have a fully mapped street network; (ii) that well-governed countries with good Internet access tend to be more complete, and that completeness has a U-shaped relationship with population density-both sparsely populated areas and dense cities are the best mapped; and (iii) that existing global datasets used by the World Bank undercount roads by more than 30%.


Assuntos
Sistemas de Informação Geográfica , Mapeamento Geográfico , Mapas como Assunto , Imagens de Satélites , Cidades , Bases de Dados Factuais , Humanos , Veículos Automotores , Instalações de Transporte
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