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151.
Comparative characterization of CD271+ and CD271− subpopulations of CD34+ human adipose‐derived stromal cells
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152.
Jo?o Victor Leite Dias Dimas Ramon Mota Queiroz Helen Rodrigues Martins David Eladio Gorla Herton Helder Rocha Pires Liléia Diotaiuti 《Memórias do Instituto Oswaldo Cruz》2016,111(1):43-50
Reports of triatomine infestation in urban areas have increased. We analysed the
spatial distribution of infestation by triatomines in the urban area of Diamantina,
in the state of Minas Gerais, Brazil. Triatomines were obtained by community-based
entomological surveillance. Spatial patterns of infestation were analysed by Ripley’s
K function and Kernel density estimator. Normalised difference vegetation index
(NDVI) and land cover derived from satellite imagery were compared between infested
and uninfested areas. A total of 140 adults of four species were captured (100
Triatoma vitticeps, 25Panstrongylus geniculatus,
8 Panstrongylus megistus, and 7 Triatoma
arthurneivai specimens). In total, 87.9% were captured within domiciles.
Infection by trypanosomes was observed in 19.6% of 107 examined insects. The spatial
distributions ofT. vitticeps, P. geniculatus,
T. arthurneivai, and trypanosome-positive triatomines were
clustered, occurring mainly in peripheral areas. NDVI values were statistically
higher in areas infested by T. vitticeps and P.
geniculatus. Buildings infested by these species were located closer to
open fields, whereas infestations of P. megistus andT.
arthurneivai were closer to bare soil. Human occupation and modification
of natural areas may be involved in triatomine invasion, exposing the population to
these vectors. 相似文献
153.
Improved Performance and Reliability of p‐i‐n Perovskite Solar Cells via Doped Metal Oxides
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Perovskite photovoltaics (PVs) have attracted attention because of their excellent power conversion efficiency (PCE). Critical issues related to large‐area PV performance, reliability, and lifetime need to be addressed. Here, it is shown that doped metal oxides can provide ideal electron selectivity, improved reliability, and stability for perovskite PVs. This study reports p‐i‐n perovskite PVs with device areas ranging from 0.09 cm2 to 0.5 cm2 incorporating a thick aluminum‐doped zinc oxide (AZO) electron selective contact with hysteresis‐free PCE of over 13% and high fill factor values in the range of 80%. AZO provides suitable energy levels for carrier selectivity, neutralizes the presence of pinholes, and provides intimate interfaces. Devices using AZO exhibit an average PCE increase of over 20% compared with the devices without AZO and maintain the high PCE for the larger area devices reported. Furthermore, the device stability of p‐i‐n perovskite solar cells under the ISOS‐D‐1 is enhanced when AZO is used, and maintains 100% of the initial PCE for over 1000 h of exposure when AZO/Au is used as the top electrode. The results indicate the importance of doped metal oxides as carrier selective contacts to achieve reliable and high‐performance long‐lived large‐area perovskite solar cells. 相似文献
154.
Amino Acid Interaction with and Adsorption on Clays: FT-IR and Mössbauer Spectroscopy and X-ray Diffractometry Investigations 总被引:1,自引:1,他引:0
Luís O. B. Benetoli Cláudio M. D. de Souza Klébson L. da Silva Ivan G. de SouzaJr Henrique de Santana Andrea PaesanoJr Antonio C. S. da Costa Cássia Thaïs B. V. Zaia Dimas A. M. Zaia 《Origins of life and evolution of the biosphere》2007,37(6):479-493
In the present paper, the adsorption of amino acids (Ala, Met, Gln, Cys, Asp, Lys, His) on clays (bentonite, kaolinite) was studied at different pH (3.00, 6.00, 8.00). The amino acids were dissolved in seawater, which contains the major elements. There were two main findings in this study. First, amino acids with a charged R group (Asp, Lys, His) and Cys were adsorbed on clays more than Ala, Met and Gln (uncharged R groups). However, 74% of the amino acids in the proteins of modern organisms have uncharged R groups. These results raise some questions about the role of minerals in providing a prebiotic concentration mechanism for amino acids. Several mechanisms are also discussed that could produce peptide with a greater proportion of amino acids with uncharged R groups. Second, Cys could play an important role in prebiotic chemistry besides participating in the structure of peptides/proteins. The FT-IR spectra showed that the adsorption of amino acids on the clays occurs through the amine group. However, the Cys/clay interaction occurs through the sulfhydryl and amine groups. X-ray diffractometry showed that pH affects the bentonite interlayer, and at pH 3.00 the expansion of Cys/bentonite was greater than that of the samples of ethylene glycol/bentonite saturated with Mg. The Mössbauer spectrum for the sample with absorbed Cys showed a large increase (~20%) in ferrous ions. This means that Cys was able to partially reduce iron present in bentonite. This result is similar to that which occurs with aconitase where the ferric ions are reduced to Fe 2.5. 相似文献
155.
The Upper Cretaceous-Paleogene genus Trinocladus that is based on T. tripolitanus Raineri, 1922, originally described from Libyan material, is morphologically well constrained. Its species are commonly distinguished on the basis of their biometrics. However, the narrow Gaussian distribution reported for some measurements may result from post-mortem dynamic sorting as suggested by a review of the surrounding microfacies. An examination of Brazilian material of the type-species suggests a slightly club-shaped thallus morphology. Two “false Permocalculus” species originally described by Johnson and the type-material of which has been reexamined are formally reascribed to the genus Trinocladus. T. budaensis, the smallest one, has slightly club-shaped thallus, too. T. elliotti is poorly mineralized and insufficiently documented. In addition to T. tripolitanus, Raineri described a tiny species which was later revised by Pia, i.e., Dissocladella ondulata. D. bonardii, a name recently introduced by Radoi?i? et al. and which is based on Raineri’s original material, is considered here as an objective junior synonym of D. ondulata. 相似文献
156.
Adrian C. Kong Alex Kitto Dimas E. Pineda Roberto A. Miki Daniel T. Alfonso Israel Alfonso 《The Iowa orthopaedic journal》2021,41(2):95
BackgroundVarious surgical techniques for treating avulsions of the flexor digitorum profundus tendon at the distal phalanx have been published but no ideal technique has emerged. We introduce a new all-internal 4-anchor flexor tendon repair technique and evaluate outcomes in three clinical cases.MethodsIn this retrospective case series, we reviewed three patients that sustained an avulsion of the flexor digitorum profundus tendon at the distal phalanx. All patients were surgically treated with the four-anchor repair technique. Two titanium anchors were inserted into the distal phalanx and two all-suture anchors were inserted distal to the first set of anchors. The tendon was then attached to these four anchors using a Krackow stitch pattern and the anchors were sown to each other. Active flexion and extension of the proximal and distal interphalangeal joint were measured at 3-month, 12-month, and 5-year follow-up. Postoperative complications were documented.ResultsAll patients achieved excellent clinical outcomes according to assessment criteria. At 3-month follow-up, all patients regained full flexion; two patients had full extension, while one patient was 3 degrees short of full extension. At 12-month follow-up, all patients had full flexion and extension. Five-year follow-up demonstrated the same results with no loss of function, sensation or grip strength. The repairs healed without rupture, and no complications were reported.ConclusionThe 4-anchor flexor tendon repair is a viable surgical technique for zone 1 flexor digitorum profundus tendon repair or reconstruction. Further studies are needed to replicate these promising results and biomechanically validate this technique.Level of Evidence: IV 相似文献
157.
Kemmer D Podowski RM Yusuf D Brumm J Cheung W Wahlestedt C Lenhard B Wasserman WW 《PloS one》2008,3(1):e1440
Background
We introduce the Gene Characterization Index, a bioinformatics method for scoring the extent to which a protein-encoding gene is functionally described. Inherently a reflection of human perception, the Gene Characterization Index is applied for assessing the characterization status of individual genes, thus serving the advancement of both genome annotation and applied genomics research by rapid and unbiased identification of groups of uncharacterized genes for diverse applications such as directed functional studies and delineation of novel drug targets.Methodology/Principal Findings
The scoring procedure is based on a global survey of researchers, who assigned characterization scores from 1 (poor) to 10 (extensive) for a sample of genes based on major online resources. By evaluating the survey as training data, we developed a bioinformatics procedure to assign gene characterization scores to all genes in the human genome. We analyzed snapshots of functional genome annotation over a period of 6 years to assess temporal changes reflected by the increase of the average Gene Characterization Index. Applying the Gene Characterization Index to genes within pharmaceutically relevant classes, we confirmed known drug targets as high-scoring genes and revealed potentially interesting novel targets with low characterization indexes. Removing known drug targets and genes linked to sequence-related patent filings from the entirety of indexed genes, we identified sets of low-scoring genes particularly suited for further experimental investigation.Conclusions/Significance
The Gene Characterization Index is intended to serve as a tool to the scientific community and granting agencies for focusing resources and efforts on unexplored areas of the genome. The Gene Characterization Index is available from http://cisreg.ca/gci/. 相似文献158.
The EICAT+ framework enables classification of positive impacts of alien taxa on native biodiversity
Giovanni Vimercati Anna F. Probert Lara Volery Ruben Bernardo-Madrid Sandro Bertolino Vanessa Cspedes Franz Essl Thomas Evans Belinda Gallardo Laure Gallien Pablo Gonzlez-Moreno Marie Charlotte Grange Cang Hui Jonathan M. Jeschke Stelios Katsanevakis Ingolf Kühn Sabrina Kumschick Jan Pergl Petr Pyek Loren Rieseberg Tamara B. Robinson Wolf-Christian Saul Cascade J. B. Sorte Montserrat Vil John R. U. Wilson Sven Bacher 《PLoS biology》2022,20(8)
Species introduced through human-related activities beyond their native range, termed alien species, have various impacts worldwide. The IUCN Environmental Impact Classification for Alien Taxa (EICAT) is a global standard to assess negative impacts of alien species on native biodiversity. Alien species can also positively affect biodiversity (for instance, through food and habitat provisioning or dispersal facilitation) but there is currently no standardized and evidence-based system to classify positive impacts. We fill this gap by proposing EICAT+, which uses 5 semiquantitative scenarios to categorize the magnitude of positive impacts, and describes underlying mechanisms. EICAT+ can be applied to all alien taxa at different spatial and organizational scales. The application of EICAT+ expands our understanding of the consequences of biological invasions and can inform conservation decisions.Various schemes assess negative impacts of alien species on native biodiversity, but alien species can also positively affect biodiversity. This Consensus View proposes EICAT+, a scheme which uses five semi-quantitative scenarios to categorise positive impacts, describes underlying mechanisms, and can be applied to all alien taxa and across various invasion contexts. 相似文献
159.
The conformation of DNA complexes formed with various 3-amino- and 3,8-diamino-phenanthridinium derivatives were examined by CD and fluorescence methods. The CD of these complexes is characterized by major bands in the 300–350-nm and the 400–550-nm regions. The CD properties of the complexes formed with diaminophenanthridinium derivatives suggest that the structure of such complexes is well represented by the intercalation complex formed between DNA and ethidium bromide. The substantial and regular increases in ellipticities near 308 nm that occur with increasing DNA-bound diaminophenanthridinium to DNA phosphate ratios (r) may result from direct interactions between molecules intercalated in neighbouring binding sites. In contrast, the changes in the shape of the CD of DNA complexes of monoaminophenanthridinium derivatives with r and the much lower maximum ellipticities attained suggest that near-neighbor interactions among intercalated monoaminophenanthridinium derivatives occur much less efficiently than in the corresponding diamino complexes, if at all. Although alternative explanations for the differences in the optical properties between the mono- and diaminophenanthridinium complexes of DNA may be offered, such results seem to indicate that complexes formed with monoaminophenanthridinium derivatives are characterized by a conformation which is quite distinct and different from that of the DNA–diaminophenanthridinium complexes. This conclusion is further supported by the considerable increase in fluorescence that accompanies the binding of the diaminophenanthridinium derivatives to DNA as compared to the minor increases, which occur upon the binding of the monoaminophenanthridinium compounds. The importance of conformation as a factor influencing template, function, especially with respect to the RNA polymerase-catalyzed synthesis of RNA, is now well appreciated. Therefore, methods which could provide information readily about changes in the conformation of a template, i.e., as a result of dye intercalation, are expected to facilitate our understanding of the effects of conformational change on the function and activity of templates. 相似文献
160.
Bruna S. Bitencourt Tiffany M. Dimas Pedro G. Da Silva Elder F. Morato 《Ecological Entomology》2020,45(2):259-268
1. The habitat heterogeneity hypothesis predicts that heterogeneous habitats may provide more niches and diverse ways of exploiting environmental resources, thereby allowing more species to coexist, persist and diversify. 2. We aimed to investigate how an edge-interior gradient related to forest complexity influences species composition, abundance and richness of dung beetles in the western Amazon rainforest. We expected dung beetle abundance and richness to increase along the forest edge-interior gradient, in accordance with the habitat heterogeneity hypothesis. We also expected strong changes in species composition driven by species turnover in the forest interior and nestedness along the forest edges. We sampled dung beetles using baited pitfall traps across an edge-interior gradient. We also assessed the variation in forest features along the edge-interior gradient to identify changes in forest complexity. 3. Both species richness and abundance of dung beetles increased along the forest edge-interior, following the gradient of forest complexity. The Sorensen dissimilarity of dung beetle assemblages was higher among sampling units placed near the forest edge, although neither turnover, nor nestedness was different between the extremes of the forest edge-interior gradient. There was a clear compositional change along the edge-interior gradient mostly driven by species turnover. Individual indicator value analysis revealed that species were strongly associated with the forest interior conditions. 4. The simplification of the Amazon rainforest near clearings causes compositional changes in dung beetle assemblages. These changes are characterised by species-poor and low-abundance assemblages and may impair dung beetle ecological functions and therefore forest recovery. 相似文献