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101.
Silas Bergen Manuela M. Huso Adam E. Duerr Melissa A. Braham Todd E. Katzner Sara Schmuecker Tricia A. Miller 《Ecology and evolution》2022,12(2)
- Recent advances in digital data collection have spurred accumulation of immense quantities of data that have potential to lead to remarkable ecological insight, but that also present analytic challenges. In the case of biologging data from birds, common analytical approaches to classifying movement behaviors are largely inappropriate for these massive data sets.
- We apply a framework for using K‐means clustering to classify bird behavior using points from short time interval GPS tracks. K‐means clustering is a well‐known and computationally efficient statistical tool that has been used in animal movement studies primarily for clustering segments of consecutive points. To illustrate the utility of our approach, we apply K‐means clustering to six focal variables derived from GPS data collected at 1–11 s intervals from free‐flying bald eagles (Haliaeetus leucocephalus) throughout the state of Iowa, USA. We illustrate how these data can be used to identify behaviors and life‐stage‐ and age‐related variation in behavior.
- After filtering for data quality, the K‐means algorithm identified four clusters in >2 million GPS telemetry data points. These four clusters corresponded to three movement states: ascending, flapping, and gliding flight; and one non‐moving state: perching. Mapping these states illustrated how they corresponded tightly to expectations derived from natural history observations; for example, long periods of ascending flight were often followed by long gliding descents, birds alternated between flapping and gliding flight.
- The K‐means clustering approach we applied is both an efficient and effective mechanism to classify and interpret short‐interval biologging data to understand movement behaviors. Furthermore, because it can apply to an abundance of very short, irregular, and high‐dimensional movement data, it provides insight into small‐scale variation in behavior that would not be possible with many other analytical approaches.
102.
Enrica Cappellozza Federico Boschi Maddalena Sguizzato Elisabetta Esposito Rita Cortesi Manuela Malatesta Laura Calderan 《European journal of histochemistry : EJH》2022,66(1)
The investigation of the absorption of drug delivery systems, designed for the transport of therapeutic molecules inside the body, could be relatively simplified by the fluorophore association and tracking by means of bio-imaging techniques (i.e., optical in vivo imaging or confocal and multiphoton microscopy). However, when a fluorescence signal comes out from the skin, its specific detection can be problematic. Skin high autofluorescence can hinder the observation of administered exogenous fluorophores conjugated to drug delivery systems, making it more challenging to detect their biodistribution. In the present study, we have developed a method based on the spectrofluorometric analysis of skin samples to discriminate the fluorescent signal coming from administered fluorescent molecules from the background. Moreover, we gave a semi-quantitative evaluation of the signal intensity. Thus, we distinguished two gel formulations loading the fluorophore rhodamine B (called GEL RHO and GEL SLN-RHO). The two formulations of gels, one of which containing solid lipid nanoparticles (GEL RHO-SLN), were administered on skin explants incubated in a bioreactor, and the penetration was evaluated at different time points (2 and 6 hours). Cryostatic sections of skin samples were observed with confocal laser scanning microscopy, and a spectrofluorometric analysis was performed. Significantly higher signal intensity in the samples administered with SLN-RHO GEL, with a preferential accumulation in the hair bulbs, was found. Reaching also the deeper layers of the hair shaft after 6 hours, the solid lipid nanoparticles thickened with polymer represent a suitable drug delivery system for transcutaneous administration.Key words: Organ culture, bioreactor, transcutaneous biodistribution, spectrofluorimetric analysis 相似文献
103.
Manuela de O. Ramalho Leonardo Menino Rodrigo F. Souza Dbora Y. Kayano Juliana M. C. Alves Ricardo Harakava Victor H. Nagatani Otvio G. M. Silva Odair C. Bueno Maria S. C. Morini 《Genetics and molecular biology》2022,45(1)
In South America, Solenopsis saevissima and S. invicta are the most common fire ants. Nests are founded in areas under anthropic interference like urban or rural areas, but S. invicta is found preferentially in those with the greatest anthropic interference. However, we do not know the rates at which they exist in anthropized areas next to high density of native vegetation. Areas with 60 to 90% of native Atlantic Forest were selected to verify the occurrence of both species in rural and urban areas. We investigated the molecular diversity and applied the reconstruction of the ancestral state analysis for each species. A total of 186 nests were analyzed and we found that the two species had the same proportion in the urban area. However, S. saevissima had a higher rate of prevalence in the rural area, in addition to having a greater number of haplotypes and ancestry associated with this type of habitat for the region. S. invicta had the same number of haplotypes in both rural and urban regions, and less haplotypic diversity. We conclude that S. saevissima is a species typically associated with rural areas and S. invicta, although present, is not dominant in urban areas. Keywords: Biodiversity, haplotype diversity, DNA barcoding, mtDNA 相似文献
104.
Manuela G. Neuman Helmut K. Seitz Rolf Teschke Stephen Malnick Kamisha L. Johnson-Davis Lawrence B. Cohen Anit German Nicolas Hohmann Bernhardo Moreira George Moussa Mihai Opris 《Current issues in molecular biology》2022,44(3):1294
Hepatic cells are sensitive to internal and external signals. Ethanol is one of the oldest and most widely used drugs in the world. The focus on the mechanistic engine of the alcohol-induced injury has been in the liver, which is responsible for the pathways of alcohol metabolism. Ethanol undergoes a phase I type of reaction, mainly catalyzed by the cytoplasmic enzyme, alcohol dehydrogenase (ADH), and by the microsomal ethanol-oxidizing system (MEOS). Reactive oxygen species (ROS) generated by cytochrome (CYP) 2E1 activity and MEOS contribute to ethanol-induced toxicity. We aimed to: (1) Describe the cellular, pathophysiological and clinical effects of alcohol misuse on the liver; (2) Select the biomarkers and analytical methods utilized by the clinical laboratory to assess alcohol exposure; (3) Provide therapeutic ideas to prevent/reduce alcohol-induced liver injury; (4) Provide up-to-date knowledge regarding the Corona virus and its affect on the liver; (5) Link rare diseases with alcohol consumption. The current review contributes to risk identification of patients with alcoholic, as well as non-alcoholic, liver disease and metabolic syndrome. Additional prevalence of ethnic, genetic, and viral vulnerabilities are presented. 相似文献
105.
R Bartoli E Lozupone L Resta 《Bollettino della Società italiana di biologia sperimentale》1990,66(1):83-89
This study reports the results of the histo-pathological investigation on the stapes (fragments or complets) of 46 patients (34 females and 12 males) with clinical diagnosis of stapedial otosclerosis and submitted to stapedectomy. Otospongiotic and otosclerotic areas have been found only in some cases; more frequently, erosion cavities filled with fibrous tissue and round-cells infiltration with lymphocytes and/or macrophages have been seen. Osteoclasts were observed only in few cases. Blue mantles have been observed in about half of the cases. Our findings show that non specific chronic inflammation should be more frequent than otospongiosis or otosclerotic foci, and indicate that a phlogosis could be the pathogenetic agent of this disease. This conclusion is in agreement with our previous research, and has been recently confirmed by the observations in stapes of otosclerotic patients of viral antigens and antibodies. 相似文献
106.
Molecular, morphological and morphometric analyses were conducted on several samples of Cainocreadium labracis (Opecoelidae), a trematode parasitic in marine teleosts. The samples were isolated from several specimens of Dicentrarchus labrax, the type host, and Dentex dentex. The molecular analysis of complete Internal Transcribed Spacer sequences of ribosomal DNA revealed that specimens isolated from each host species form two well-defined groups, whose sequence divergence reaches 7.5%. The morphological study showed that the two groups can be distinguished by several characters, including the level of maximum body breadth, the relative position of the testes, the shape of the cirrus pouch, and the extent of the uterus. Multivariate analyses of morphometrics demonstrated consistency of most of the characters for discriminating the two groups. Our results show that C. labracis specimens isolated from D. labrax and D. dentex represent clearly distinct entities from molecular, morphological and statistical points of view, which has enabled us to describe a new species, Cainocreadium dentecis n. sp. 相似文献
107.
108.
109.
Pereira MM Bandeiras TM Fernandes AS Lemos RS Melo AM Teixeira M 《Journal of bioenergetics and biomembranes》2004,36(1):93-105
Thermophiles are organisms that grow optimally above 50 degrees C and up to approximately 120 degrees C. These extreme conditions must have led to specific characteristics of the cellular components. In this paper we extensively analyze the types of respiratory complexes from thermophilic aerobic prokaryotes. The different membrane-bound complexes so far characterized are described, and the genomic data available for thermophilic archaea and bacteria are analyzed. It is observed that no specific characteristics can be associated to thermophilicity as the different types of complexes I-IV are present randomly in thermophilic aerobic organisms, as well as in mesophiles. Rather, the extensive genomic analyses indicate that the differences concerning the several complexes are related to the organism phylogeny, i.e., to evolution and lateral gene transfer events. 相似文献
110.
Tormopsolus orientalis Yamaguti, 1934, is redescribed from Seriola dumerili from off Corsica, Majorca and Águilas, SE Spain. The vitellarium is interrupted at the level of the ovary and both testes, and a bipartite seminal vesicle is found in many specimens. Oral sucker papillae are always seen. Type-specimens and voucher specimens from off Japan, Bermuda, Panama, Curaçao and the Great Barrier Reef have been compared with the Mediterranean species. Specimens of T. medius Reimer, 1983, from Mozambique have been studied and this species is synonymised with T. orientalis. 相似文献