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51.
The carbon footprint of flying overseas to conferences, meetings, and workshops to share and build knowledge has been increasingly questioned over the last two decades, especially in environmental and climate sciences, due to the related colossal carbon emissions. Here, we infer the value of scientific meetings through the number of publications produced either directly or indirectly after attending a scientific conference, symposium, or workshop (i.e., the conference‐related production) and the number of publications produced per meeting (i.e., the conference‐related productivity) as proxies for the academic value of these meetings, and relate them to both the number of meetings attended and the related carbon emissions. We show that conference‐related production and productivity, respectively, increase and decay with the number of meetings attended, and noticeably that the less productive people exhibit the largest carbon footprint. Taken together, our results imply that a twofold decrease in the carbon footprint of a given scientist would result in a twofold increase in productivity through a fivefold decrease in the number of meeting attended. In light of these figures, we call for both the implementation of objective and quantitative criteria related to the optimum number of conferences to attend in an effort to maximize scientific productivity while minimizing the related carbon footprint, and the development of a rationale to minimize the carbon emission related to scientific activities. 相似文献
52.
Luiz A. R. Freitas Lilian V. S. Carvalho Jonathan L. M. Fontes Cassiana S. Souza Reginaldo B. Santos Jr. Lara T. Cardoso Claudio P. Figueira Milton S. Fonseca Neto Rafael C. M. F. Dias Manuela S. Solc Marilda S. Gonalves Setondji C. M. A. Yahouedehou Ceuci L. X. Nunes Geraldo G. S. Oliveira Washington L. C. dosSantos 《Journal of cellular and molecular medicine》2021,25(21):10318
53.
Unai López-de-Heredia Pilar Jiménez Pedro Díaz-Fernández Luis Gil 《Journal of Biogeography》2005,32(6):939-949
Aim To analyse the role of the Balearic Islands as a refuge area for evergreen Quercus (cork oak: Quercus suber L., holm oak: Q. ilex L., kermes oak: Q. coccifera L.), by using molecular, historical and palaeobotanical data. Location The Western Mediterranean Basin (Balearic Islands, eastern Iberia, Provence, Sardinia, Corsica, Sicily, Malta, Italy, Northern Africa). Methods We sampled 108 populations and used the PCR‐RFLP technique with five universal cpDNA primers to define haplotypes in the sampled populations. Diversity, differentiation parameters and spatial analysis of the populations, using a spatial version of amova , were linked to the geological history of the Western Mediterranean Basin in order to explain the present spatial pattern of the evergreen Quercus populations in the Balearics. Results Evergreen Quercus cpDNA shows a complex structure, with remnants of ancient diversity in the Balearics. Balearic populations of holm oak are related to Iberian populations, while for cork and kermes oaks, we found both Tyrrhenian and Iberian haplotypes. Main conclusions The complex spatial patterns of cpDNA in Balearic evergreen Quercus appears explicable in terms of a combination of physical (vicariance and long distance dispersal) and biological (introgressive hybridization) factors. The Balearics constitute a glacial refuge area and a reservoir of genetic variation with traces of ancient diversity from Messinian–Pliocene stages. 相似文献
54.
A. G. Ponomarenko 《Paleontological Journal》2008,42(6):600-606
Beetle remains from the Triassic Khey-Yaga locality, Nenets National District, Korotaikha Basin, Nyadeita Formation, Olenekian-Anisian are described. Only isolated elytra have been found. Tetracoleus tshalyshevi gen. et sp. nov. and T. minimus sp. nov. are described and assigned to Tricoleidae, and six new species are described in formal taxa. Tetracoleus is close to Permian tricoleids just found in the Newcastle Group of Australia and the Vyatkian Aristovo locality of northern European Russia. The composition of elytra in the locality is closer to that of Lower Triassic localities than other Middle Triassic localities and characterizes the beginning of a recovery after the Permian-Triassic ecological crisis. Longxianocupes Hong in Liu, Liu et Hong, 1985 is shown to be a junior synonym of Sogdelytron Ponomarenko, 1969. The species Palademosyne ovum Ponomarenko, 2004, P. elongatum Ponomarenko, 2004, and P. latum Ponomarenko, 2004 are transferred to the genus Pseudochrysomelites Handlirsch, 1906. 相似文献
55.
BACKGROUND: Bone density is the most important determinant of osteoporotic fractures, which lead to significant morbidity, disability and mortality for older persons, particularly women. Sensitive periods for bone mineralization in infancy, childhood and adolescence overlap with those for height attainment. After peak density is reached in early adulthood, there is age-related decline. We ask whether bone density, as height, reflects economic conditions. SUBJECTS AND METHODS: Using the third National Health and Nutrition Examination Survey, a probability sample of the US population which over-sampled Blacks and Mexican Americans, we examine the associations between adult bone mineral content (BMC) adjusted for bone and body size and three economic indicators: education, height and the poverty income ratio (PIR). We compare four groups: US-born Whites, Blacks and Mexican Americans and Mexican-born Mexican Americans. RESULTS: Education is positively associated with BMC only for White women, although there are similar, non-significant associations for Black women and White and Black men. For women, BMC is more strongly associated with height for Mexican Americans, especially the Mexican-born, than for Whites. For men, the only significant association is a negative one with education for men born in Mexico. PIR is not significantly associated with BMC, although there is pattern of lower income being associated with lower BMC for Whites and Blacks and higher BMC for Mexican Americans. CONCLUSION: Bone density does not reflect economic conditions as strongly or consistently as does physical stature. However, for women there is evidence that lower economic status in childhood or adolescence is associated with lower bone density. 相似文献
56.
Elwin G. Smith Rosemarie A. De Clerck-Floate Brian H. Van Hezewijk James R. Moyer Eva Pavlik 《Biological Control》2009,48(3):281-286
The cost of rearing the root-feeding weevil, Mogulones cruciger Herbst, to control the invasive weed houndstongue (Cynoglossum officinale L.) was determined for two managed production methods. Production in an insectary setting provides control over rearing and all adult weevils that emerge can be collected, but required facility investment and high labor input. Mass-rearing in a managed ‘field crop’ setting required less facilities and labor while the insects were multiplying, but capture of the emerged adults was challenging and labor intensive. Estimated per adult weevil production costs were $CDN 2.65 for the insectary approach, and from $CDN 0.10 to $CDN 0.14 for mass-rearing in the managed field crop setting. Even though collection of adult weevils in the field crop production system was challenging, commercial production of M. cruciger should consider use of this mass-rearing method because of its lower cost. 相似文献
57.
Ana I. Dittel Charles E. Epifanio 《Journal of experimental marine biology and ecology》2009,374(2):79-92
The Chinese mitten crab Eriocheir sinensis is a native of freshwater and estuarine habitats along the east coast of Asia. Invasive populations have existed in northern Europe since the early 20th century, and more recently a breeding population has become established in the San Francisco Bay system along the west coast of North America. Ballast water is the most probable vector for both invasions, although there is also potential for escape from ethnic markets and from the ornamental aquarium industry. Invasive populations of mitten crabs have caused millions of dollars in economic and ecological damage. Economic impacts center largely on the burrowing activity of the crabs, which damages stream banks and levees, and the annual spawning migration, which interferes with fishing activities and irrigation projects. Chinese mitten crabs have recently appeared in the Chesapeake and Delaware Bays on the east coast of the USA, and there are confirmed reports of breeding females in both estuaries. The potential for large populations of mitten crabs in these estuaries has not been determined. This paper presents a review of the biology and ecology of native and invasive populations of the species and provides recommendations for research relevant to the prediction of future mitten crab invasions. 相似文献
58.
Coren L. Apicella Alyssa N. Crittenden Victoria A. Tobolsky 《Evolution and human behavior》2017,38(5):592-603
Observed economic and labor disparities between the sexes may, in part, result from evolved sex differences in risk preferences. Using incentivized economic games, we report on sex differences in risk preferences in the Hadza, a population of hunter-gatherers. One game played in 2010 (n = 233) found that more Hadza males than females prefer to gamble for a chance to earn more maize rather than settle for a sure, but smaller, amount. Similarly, a second game played in 2013 (n = 102) found that male Hadza gamble a greater proportion of honey for a chance to earn more compared to female Hadza. Effect sizes are small to medium. We find weak evidence that risk-taking increases in men as their mating opportunities increase. In both games, the sex difference widens throughout childhood and is greatest among adolescents; though note that child samples are small. We explore developmental trends further using observational data on food returns in children (n = 357). Our data suggest that while the mean number of calories boys bring to camp remains stable with age, the variance in their caloric returns increases. Among girls, the variance remains stable with increased age. Both the economic games and food return data are consistent with the sexual division of labor wherein boys, beginning in late childhood, begin to target riskier foods. To the extent that the Hadza allow us to make inferences about long-standing patterns of human behavior, we suggest that sex differences in risk preferences may have been present long before agriculture and the modern work environment. 相似文献
59.
Xiaoyu Huang Xueting An Xue Gao Ningning Wang Jia Liu Yong Zhang Guoyan Qi Chao Zhang 《Journal of neurochemistry》2024,168(3):224-237
Serum amyloid A (SAA) is a clinically useful inflammatory marker involved in the pathogenesis of autoimmune diseases. This study aimed to explore the SAA levels in a cohort of patients with myasthenia gravis (MG) in relation to disease-related clinical parameters and myasthenic crisis (MC) and elucidate the effects of SAA on immune response. A total of 82 MG patients including 50 new-onset MG patients and 32 MC patients were enrolled in this study. Baseline data and laboratory parameters of all enrolled MG patients were routinely recorded through electronic medical systems. SAA levels were measured by enzyme-linked immunosorbent assay (ELISA) kit. CD4+ T and CD19+ B cell subsets were analyzed by flow cytometry. In vitro, human recombinant SAA (Apo-SAA) was applied to stimulate peripheral blood mononuclear cells (PBMCs) from MG patients to observe the effect on T and B cell differentiation. Our results indicated that SAA levels in new-onset MG patients were higher than those in controls and were positively correlated with QMG score, MGFA classification, plasmablast cells, IL-6, and IL-17 levels. Subgroup analysis revealed that SAA levels were increased in generalized MG (GMG) patients than in ocular MG (OMG), as well as elevated in late-onset MG (LOMG) than in early-onset MG (EOMG) and higher in MGFA III/IV compared with MGFA I/II. The ROC curve demonstrated that SAA showed good diagnostic value for MC, especially when combined with NLR. In vitro, Apo-SAA promoted the Th1 cells, Th17 cells, plasmablast cells, and plasma cells differentiation in MG PBMCs. The present findings suggested that SAA was increased in MG patients and promoted expansion of CD4+ T cell and CD19+ B cell subsets, which implicated in the severity of MG patients.
60.
The inclusion of carbon stock enhancements under the Reducing Emissions from Deforestation and Forest Degradation (REDD+) framework will likely drive a rapid increase in biosequestration projects that remove carbon from the atmosphere through rehabilitation of degraded primary rain forests. Such projects could also present an important opportunity to reverse losses of biodiversity from degraded rain forests, but concern has recently been expressed that management interventions to increase carbon stocks may conflict with biodiversity conservation. Focusing on a large‐scale rain forest rehabilitation project in northern Borneo, we examine: (i) how intensive rehabilitation of selectively logged forests affected patterns of bird community composition and (ii) whether changes in vegetation structure explain observed shifts in avian guild structure and species composition. Bird composition differed between unlogged, naturally regenerating logged, and rehabilitated logged habitats, with the avifauna of rehabilitated forest more similar to that of naturally regenerating forest. Crucially, rehabilitation did not adversely affect either those species that declined after logging or those species that are IUCN Red Listed. Rehabilitation reduced the prevalence of vines and shrubs within regenerating forest, and across all habitats, the abundance and species richness of all birds and of obligate frugivores were positively related to vine prevalence. In contrast, the abundance and richness of frugivore–insectivore generalists and of salliers were negatively related to vines, suggesting that avifaunal responses to forest rehabilitation were attributable to liberation cutting of vines. Management intervention to increase carbon stocks had little adverse effect on avian biodiversity and we therefore argue that rain forest rehabilitation should play a strong role in future REDD+ agreements. 相似文献