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71.
This work presents the optimized luminescence spectra for the Ce3+,Sm3+-doped NaSrPO4 phosphor that was synthesized using a wet chemical method. Ce3+ and Sm3+ are activator impurities that show spectral splitting bands that corresponds to the d–f and f–f transitions, respectively. These impurity elements shows the characteristics spectral bands when doped with the NaSrPO4 host lattice. Spectral splitting in the Ce3+ excitation band was monitored in the 240–340 nm range, in which the observed bands were located at 269 nm, 292 nm and 321 nm, and emission bands were observed in the broad spectral range 330–430 nm. However, when Sm3+ ion was doped in the same host lattice we obtained a characteristic emission band at 590 and 645 nm in the orange–red region, under sharp excitation bands located at 345, 361, 375, and 403 nm respectively. Also, we carried out energy transfer analysis in the Ce3+/Dy3+-doped NaSrPO4 phosphor. Further crystalline phase and the nanophase nature of the phosphor compound were confirmed using X-ray diffraction and transmission electron microscopy analyses. 相似文献
72.
The spatial extent of animal movement is a key consideration when designing conservation measures, such as marine protected areas. Methods to assess territory size in the marine environment, however, are labour intensive and/or expensive. Here, we explore a novel method to investigate the spatial ecology of territorial fishes by examining their reactions to an artificial light stimulus. During benthic towed video surveys conducted in Lyme Bay, southwest England, several species of wrasse (Labridae) have frequently been observed pursuing a laser projected onto the seabed. While the motivation behind ‘laser‐chasing’ is unclear, we quantified the spatial aspects of this behaviour by comparing chase distance and chase likelihood between and within species, to determine the potential utility of this method for investigating space use and aggression in wild fishes. Cuckoo wrasse (Labrus mixtus) were significantly more likely to display agonistic behaviour towards the laser than Goldsinny wrasse (Ctenolabrus rupestris). Goldsinny wrasse displayed a positive relationship between total length and chase‐distance, but not Cuckoo wrasse. The observed species differences may relate to behavioural factors affecting the motivation behind ‘laser‐chasing’, which is discussed. Chases by the cuckoo wrasse were significantly longer than those by Goldsinny wrasse, and these chase distances were used to estimate theoretical territory sizes for each species. To our knowledge, this is the first study to explore the spatial aspects of the reactions to an artificial stimulus by wild fishes. The potential to develop the method to directly investigate aspects of territoriality and aggression in wild fishes is discussed, including necessary further refinements and testing. Wild wrasses are increasingly exploited in Europe to provide cleaner fish for salmonid aquaculture, and we encourage the development of methods to inform spatial conservation measures for these ubiquitous and iconic species. 相似文献
73.
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75.
Miguel Amzquita Geny Carolina Silva Diego Antonio Restrepo Linda Margarita Ibata Rafael Nio Maximiliano Bustacara Víctor Alexander Senz Dieric Anderson Díaz Milena Alarcn Luz Adriana Quintero 《Biomédica : revista del Instituto Nacional de Salud》2022,42(2):290
Introduction:
The detection of the human papillomavirus (HPV) through the combination of the HPV test and other techniques such as cytology has impacted the detection and timely treatment of lesions associated with cervical cancer.Objective:
To estimate the budgetary impact of the strategy of early detection of HPV with DNA test genotyping with reflex cytology versus conventional cytology in women aged 30 to 65 years attending the cervical cancer screening program at a health benefit managing entity in Colombia.Materials and methods:
Using a decision tree and a Markov model, the clinical implications and direct costs of screening, diagnosis, and treatment were estimated in a cohort of women. The analysis considered two screening cycles and their annual costs. The data on the prevalence of clinical results and the costs were taken from the health managing entity. The information on the progression, persistence, and regression of the health states were taken from the ATHENA study.Results:
The screening scheme with the HPV test, genotyping, and reflex cytology compared to conventional cytology was cost-saving. The average cost per screening cycle with the HPV test was estimated at COP $ 129,201,363 and with cytology at COP $ 186,309,952, i.e., a saving of COP $ 57,108,589 (30.7%).Conclusion:
The implementation of the screening strategy under evaluation suggests prospective savings derived from the early detection of health states associated with the development of cervical cancer. 相似文献76.
Akihiro Saito Mizuho Shimizu Hitomi Nakamura Shoko Maeno Riko Katase Eitaro Miwa Kyoko Higuchi Kintake Sonoike 《FEBS letters》2014
HvLhcb1 a major light-harvesting chlorophyll a/b-binding protein in barley, is a critical player in sustainable growth under Fe deficiency. Here, we demonstrate that Fe deficiency induces phosphorylation of HvLhcb1 proteins leading to their migration from grana stacks to stroma thylakoid membranes. HvLhcb1 remained phosphorylated even in the dark and apparently independently of state transition, which represents a mechanism for short-term acclimation. Our data suggest that the constitutive phosphorylation-triggered translocation of HvLhcb1 under Fe deficiency contributes to optimization of the excitation balance between photosystem II and photosystem I, the latter of which is a main target of Fe deficiency. 相似文献
77.
coResearchers have long appreciated the significant relationship between body size and an animal's overall adaptive strategy and life history. However, much more emphasis has been placed on interpreting body size than on the actual calculation of it. One measure of size that is especially important for human evolutionary studies is stature. Despite a long history of investigation, stature estimation remains plagued by two methodological problems: (1) the choice of the statistical estimator, and (2) the choice of the reference population from which to derive the parameters.This work addresses both of these problems in estimating stature for fossil hominids, with special reference to A.L. 288-1 (Australopithecus afarensis) and WT 15000 (Homo erectus). Three reference samples of known stature with maximum humerus and femur lengths are used in this study: a large (n=2209) human sample from North America, a smaller sample of modern human pygmies (n=19) from Africa, and a sample of wild-collected African great apes (n=85). Five regression techniques are used to estimate stature in the fossil hominids using both univariate and multivariate parameters derived from the reference samples: classical calibration, inverse calibration, major axis, reduced major axis and the zero-intercept ratio model. We also explore a new diagnostic to test extrapolation and allometric differences with multivariate data, and we calculate 95% confidence intervals to examine the range of variation in estimates for A.L. 288-1, WT 15000 and the new Bouri hominid (contemporary with [corrected] Australopithecus garhi). Results frequently vary depending on whether the data are univariate or multivariate. Unique limb proportions and fragmented remains complicate the choice of estimator. We are usually left in the end with the classical calibrator as the best choice. It is the maximum likelihood estimator that performs best overall, especially in scenarios where extrapolation occurs away from the mean of the reference sample. The new diagnostic appears to be a quick and efficient way to determine at the outset whether extrapolation exists in size and/or shape of the long bones between the reference sample and the target specimen. 相似文献
78.
Judith C. Madden Vera Rogiers Mathieu Vinken 《Philosophical transactions of the Royal Society of London. Series B, Biological sciences》2014,369(1656)
There is a long history of using both in silico and in vitro methods to predict adverse effects in humans and environmental species where toxicity data are lacking. Currently, there is a great deal of interest in applying these methods to the development of so-called ‘adverse outcome pathway’ (AOP) constructs. The AOP approach provides a framework for organizing information at the chemical and biological level, allowing evidence from both in silico and in vitro studies to be rationally combined to fill gaps in knowledge concerning toxicological events. Fundamental to this new paradigm is a greater understanding of the mechanisms of toxicity and, in particular, where these mechanisms may be conserved across taxa, such as between model animals and related wild species. This presents an opportunity to make predictions across diverse species, where empirical data are unlikely to become available as is the case for most species of wildlife. 相似文献
79.
由于人类活动导致的海洋生境、生态系统以及生物资源的衰退已经引起了全球的高度重视。以生态修复的原理为基础,综述了海洋生境修复和生物资源养护的关键设施、关键技术、监测与效果评价以及综合管理的国内外研究进展,并对海洋生境修复与生物资源养护的研究热点和重点进行了展望,以期为我国海洋生境修复和生物资源养护提供参考。 相似文献
80.
BACKGROUND AND AIMS: The objective of this study is to examine the palynological diversity of Balsaminaceae (two genera/+/-1000 species), Tetrameristaceae (two genera/two species) and Pellicieraceae (one genus/one species). The diversity found will be used to infer the systematic value of pollen features within the balsaminoid clade. METHODS: Pollen morphology and ultrastructure of 29 species, representing all families of the balsaminoid clade except Marcgraviaceae, are investigated by means of light microscopy, scanning electron microscopy and transmission electron microscopy. KEY RESULTS: Balsaminaceae pollen is small to medium sized with three to four apertures, which can be either colpate or porate, and a sexine sculpturing varying from coarsely reticulate to almost microreticulate. Tetrameristaceae pollen is small sized, 3-colporate, with a heterobrochate reticulate sculpturing and granules present in the lumina. Pellicieraceae pollen is large sized, 3-colporate with long ectocolpi and a perforate sexine sculpturing with large verrucae. Furthermore, Pelliciera is characterized by the occurrence of aggregated orbicules, while orbicules are completely absent in both Balsaminaceae and Tetrameristaceae. Balsaminaceae pollen differs from the other balsaminoid families due to the occurrence of colpate or porate grains with an oblate to peroblate shape, a very thin foot layer and a lamellated endexine. CONCLUSIONS: From a pollen morphological point of view, Balsaminaceae are completely different from the other balsaminoid families. Therefore, no pollen morphological synapomorphies could be defined for the balsaminoid clade. However, various pollen features were observed that could indicate a possible relationship between Tetrameristaceae, Pellicieraceae and Marcgraviaceae. Despite the palynological similarities in the latter three families, it remains unclear to what extent they are related to each other. 相似文献