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991.
Citizen science is a research practice that relies on public contributions of data. The strong recognition of its educational value combined with the need for novel methods to handle subsequent large and complex data sets raises the question: Is citizen science effective at science? A quantitative assessment of the contributions of citizen science for its core purpose – scientific research – is lacking. We examined the contribution of citizen science to a review paper by ornithologists in which they formulated ten central claims about the impact of climate change on avian migration. Citizen science was never explicitly mentioned in the review article. For each of the claims, these ornithologists scored their opinions about the amount of research effort invested in each claim and how strongly the claim was supported by evidence. This allowed us to also determine whether their trust in claims was, unwittingly or not, related to the degree to which the claims relied primarily on data generated by citizen scientists. We found that papers based on citizen science constituted between 24 and 77% of the references backing each claim, with no evidence of a mistrust of claims that relied heavily on citizen-science data. We reveal that many of these papers may not easily be recognized as drawing upon volunteer contributions, as the search terms “citizen science” and “volunteer” would have overlooked the majority of the studies that back the ten claims about birds and climate change. Our results suggest that the significance of citizen science to global research, an endeavor that is reliant on long-term information at large spatial scales, might be far greater than is readily perceived. To better understand and track the contributions of citizen science in the future, we urge researchers to use the keyword “citizen science” in papers that draw on efforts of non-professionals. 相似文献
992.
Jingbo Pang Davina H. Rhodes Maria Pini Rand T. Akasheh Karla J. Castellanos Robert J. Cabay Dianne Cooper Mauro Perretti Giamila Fantuzzi 《PloS one》2013,8(2)
Obesity and type 2 diabetes are associated with increased production of Galectin-3 (Gal-3), a protein that modulates inflammation and clearance of glucose adducts. We used Lean and Diet-induced Obese (DIO) WT and Gal-3 KO mice to investigate the role of Gal-3 in modulation of adiposity, glucose metabolism and inflammation. Deficiency of Gal-3 lead to age-dependent development of excess adiposity and systemic inflammation, as indicated by elevated production of acute-phase proteins, number of circulating pro-inflammatory Ly6Chigh monocytes and development of neutrophilia, microcytic anemia and thrombocytosis in 20-week-old Lean and DIO male Gal-3 KO mice. This was associated with impaired fasting glucose, heightened response to a glucose tolerance test and reduced adipose tissue expression of adiponectin, Gal-12, ATGL and PPARγ, in the presence of maintained insulin sensitivity and hepatic expression of gluconeogenic enzymes in 20-week-old Gal-3 KO mice compared to their diet-matched WT controls. Expression of PGC-1α and FGF-21 in the liver of Lean Gal-3 KO mice was comparable to that observed in DIO animals. Impaired fasting glucose and altered responsiveness to a glucose load preceded development of excess adiposity and systemic inflammation, as demonstrated in 12-week-old Gal-3 KO mice. Finally, a role for the microflora in mediating the fasting hyperglycemia, but not the excessive response to a glucose load, of 12-week-old Gal-3 KO mice was demonstrated by administration of antibiotics. In conclusion, Gal-3 is an important modulator of glucose metabolism, adiposity and inflammation. 相似文献
993.
Summary PJU78 is a 2.9-kb cloned human DNA segment derived from Xq24-q26. When used as a hybridization probe, it detects some 25 related sequences dispersed over the genome, including several autosomes and the X and Y chromosomes. Several pJU78-related sequences were chromosomally allocated and five different restriction fragment length polymorphisms detected and partially characterized in population and family studies. This sequence family was not found in non-primate species. The sequence appears to lack CpG-island character and is not detectably expressed in a variety of human tissues. 相似文献
994.
Bernadette Sánchez Kevin D. Pinkston Adina C. Cooper Carlos Luna Shelby T. Wyatt 《应用发育科学》2018,22(1):14-28
The aim of this study was to investigate the processes involved in developing close peer mentoring relationships among African American and Latino male adolescents in a school-based, group peer mentoring program. Qualitative one-on-one in-depth interviews were conducted with six school staff members, who administer the program, and 26 program participants about their experiences in the mentoring program. Data analysis revealed five program processes that led to close mentoring relationships: (a) rapport-building activities, (b) safe space, (c) mutual support, (d) group identity, and (e) trust. These processes ultimately led to bonding and friendship among program members, which further solidified the previous processes. Implications and future directions are discussed. 相似文献
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997.
Jonathan A. Cooper 《The Journal of cell biology》2013,201(5):725-740
Synaptic vesicles are embedded in a complex filamentous network at the presynaptic terminal. Before fusion, vesicles are linked to the active zone (AZ) by short filaments (tethers). The identity of the molecules that form and regulate tethers remains unknown, but Rab3-interacting molecule (RIM) is a prominent candidate, given its central role in AZ organization. In this paper, we analyzed presynaptic architecture of RIM1α knockout (KO) mice by cryo–electron tomography. In stark contrast to previous work on dehydrated, chemically fixed samples, our data show significant alterations in vesicle distribution and AZ tethering that could provide a structural basis for the functional deficits of RIM1α KO synapses. Proteasome inhibition reversed these structural defects, suggesting a functional recovery confirmed by electrophysiological recordings. Altogether, our results not only point to the ubiquitin–proteasome system as an important regulator of presynaptic architecture and function but also show that the tethering machinery plays a critical role in exocytosis, converging into a structural model of synaptic vesicle priming by RIM1α. 相似文献
998.
Don G. Benson JR. 《Biotechnic & histochemistry》1966,41(3):155-158
Paraffin sections from tissue fixed 4-12 hr in 10% formalin containing 0.5% cetyl pyridinium chloride, and washed 2 hr, were stained as follows: (1) Hydrolyze in 5 N HCl at room temperature for 8.5-9 min, or use standard Feulgen hydrolysis at 60 C. (2) Stain in azure A-Schiff, 0.5% in bisulfite bleach (1 N HCl, 5; 10% Na2S2O5, 5; and distilled water 90—parts by volume) for 10 min. (3) Place in bisulfite bleach 2 changes, 2 min each; wash in water, 1-2 min. (4) Stain in Alcian blue (0.1% in 0.01 2V HCl, pH 2.0) for 10 min. (5) Place in 0.01 N HCl for 2-3 min; wash in water for 1-2 min. (6) Oxidize in 0.5% HIO4 for 5 min; wash in water, 1-2 min. (7) Stain in Schiff's leucofuchsiu, 10 min. (8) Treat with bisulfite bleach as in step 3; wash in running water, 10 min. (9) Stain in naphthol yellow S (0.01% in 1% acetic acid) for 1-2 min. (10) Place in 1% acetic acid for 2 min, dehydrate in tertiary butanol, clear and cover. Result: DNA is deep blue; acidic mucins are light blue; neutral polysaccharides, red to magenta; and proteins, yellow. Proper timing of the hydrolysis for the Feulgen reaction is the most critical step. Overhydrolysis results in green nuclei (staining by naphthol yellow S) whereas purplish nuclei are the results of insufficient hydrolysis. 相似文献
999.
Summary Myocardial preservation during open heart surgery in children was studied using biopsies of the right ventricle taken at the beginning and end of a bypass with a Tru-Cut biopsy needle. Three assessments were used: (1) semi-quantitative cytochemical grading of Baker's acid haematein reaction, and the distribution of succinate dehydrogenase and myosin ATPase; (2) microdensitometry of the succinate dehydrogenase activity; and (3) quantitative birefringence measurements to assess the response of the myocardial fibres to ATP and calcium. For each assessment, the values at the beginning and end of the bypass were compared. In a series of 42 children, two died in low cardiac output and three others required substantial inotropic support. No patient showed deterioration in the overall cytochemical assessment. Two patients showed deterioration in birefringence, one died and one had low cardiac output. The remaining three patients who had post-operative problems had low birefringence values at the beginning of bypass. Thirty-two patients were used for the microdensitometric assays, one died and three required substantial inotropic support. Succinate dehydrogenase activity decreased significantly during bypass in only two patients. One of these died and the other required substantial inotropic support. 相似文献
1000.
J R Cooper 《Life sciences》1989,45(21):2041-2042
In experiments where the release of labeled acetylcholine is to be determined, the addition of choline oxidase to the incubation medium prevents any reuptake of choline. In addition, since betaine, the oxidation product of choline is not extractable into tetraphenylboron - butyronitrile, no further procedure to eliminate choline is required. 相似文献