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1.
Castel di Guido near Rome is one of the few open air Middle Pleistocene European sites that has yielded hominid skeletal remains associated with fossil fauna and Acheulean implements. The fossil hominid bones include two femoral shafts, respectively designated Castel di Guido-1 (CdG-1) and CdG-2, an occipital fragment (CdG-3), a right maxilla lacking teeth (CdG-4), a portion of right parietal (CdG-5), a right temporal (CdG-6), and a fragment of left parietal vault (CdG-7). CdG-1 through CdG-4 were collected in 1979-1982 on the surface, together with fossil fauna, where ploughing incised fossiliferous tuffaceous sands. Excavations conducted in the same area from 1980 to 1990 led to the discovery of CdG-5, CdG-6 and CdG-7 within the tuffaceous sands, which were shown to overlay a bone-bearing paleosurface, with abundant evidence of hominid activities. The Castel di Guido hominid assemblage poses intriguing taphonomic questions. The analysis of the physical evidence offered by the bone surfaces, reported in the present study, indicates that the hominid skeletal remains were heavily fragmented before fossilization and exposed to carnivores and rodents, as well as to trampling and/or friction in abrasive sediment. Although definitive conclusions cannot be reached on the basis of the available evidence, it is possible that clusters of incisions localized on specific regions of the Castel di Guido fossil hominid bones might reflect deliberate human manipulations.  相似文献   

2.
Albumin Castel di Sangro is a rare fast-moving variant of human serum albumin which has been discovered in heterozygous form in the serum of an 85-year-old woman living in Castel di Sangro (Abruzzo, Italy). Isoelectric focusing analysis of CNBr fragments from the purified variant allowed us to localize the mutation in fragment CNBr VI (residues 447-548). This fragment was isolated on a preparative scale and subjected to tryptic digestion. Sequential analysis of the abnormal tryptic peptide, purified by reverse-phase and cation-exchange HPLC, revealed that the variant arises from the substitution of lysine 536 by glutamic acid. This amino acid replacement, probably due to a single-base substitution in the structural gene, causes a change in the net charge of -2 units, which is in keeping with both the increased electrophoretic mobility of the native protein and the isoelectric point of the modified CNBr fragment.  相似文献   

3.
4.
Iori A  Di Paolo M 《Parassitologia》1999,41(Z1):53-55
In the present note are reported the results of preliminary studies on tick distribution in two wildlife areas of Abruzzo (National Park of Abruzzo, a mountainous area, approximately 40,000 ha, in Central Apennines, interesting Abruzzo, Latium and Molise regions) and Latium (Capocotta-Castel Porziano Presidential reserve, on the Tyrrhenian coast, 30 km from Rome). Sampling of ticks from domestic and wild mammals as well as from vegetation, was performed in three different areas of the National Park in 1995. Tick species identified include Rhipicephalus bursa, R. sanguineus, Hyalomma marginatum, Haemaphysalis punctata, Dermacentor marginatus, Ixodes ricinus, I. hexagonus. The presence of I. ricinus was discontinuous and sporadic. In Capocotta estate, samplings were performed bimonthly from March to November 1997 in an restricted area (1 ha) with typical Mediterranean flora and fauna. The following species were collected: I. ricinus, Haemaphysalis concinna, D. marginatus, R. bursa, Hy. marginatum. There was a high dominance of I. ricinus and H. concinna.  相似文献   

5.
Sighting frequency of tortoises (Testudo hermanni), standardized by the number of person-hours of field effort, was studied between 1992 and 2013 at three different study areas in central Italy. Although the frequency of tortoise sightings fluctuated substantially across years and among study areas, there was a significant declining trend in all the three areas, with GLM analyses showing also a significant interaction between study area and sampling year. The decreasing trend was higher in Castel Fusano than in the other two sites, with yearly frequency of sightings being independent of search effort in all of the study areas. These trends may indicate population declines, because no other explanations seem plausible. Total rainfall from previous autumn to the study period was positively correlated to tortoise sightings in only one locality. The yearly frequency of sightings of juvenile tortoises did not vary significantly among study areas and across years, thus indicating that simple differences in detectability cannot explain the observed patterns. Summer fires and forest overgrowing seem to explain the tortoise decline in two study areas (Castel Fusano and Oriolo) whereas we were not able to identify any specific reason for tortoise decline in the third study area (Manziana).  相似文献   

6.
The Castel di Guido site, with an estimated age of approximately 300,000 years, has yielded abundant animal remains, Acheulian stone and bone bifaces, and small tools. On the surface of the original deposit, turned over by agricultural activities, fragments of human remains were discovered between 1980 and 1986, including a temporal bone described here.  相似文献   

7.
The use of quantitative metrics to gauge the impact of scholarly publications, authors, and disciplines is predicated on the availability of reliable usage and annotation data. Citation and download counts are widely available from digital libraries. However, current annotation systems rely on proprietary labels, refer to journals but not articles or authors, and are manually curated. To address these limitations, we propose a social framework based on crowdsourced annotations of scholars, designed to keep up with the rapidly evolving disciplinary and interdisciplinary landscape. We describe a system called Scholarometer, which provides a service to scholars by computing citation-based impact measures. This creates an incentive for users to provide disciplinary annotations of authors, which in turn can be used to compute disciplinary metrics. We first present the system architecture and several heuristics to deal with noisy bibliographic and annotation data. We report on data sharing and interactive visualization services enabled by Scholarometer. Usage statistics, illustrating the data collected and shared through the framework, suggest that the proposed crowdsourcing approach can be successful. Secondly, we illustrate how the disciplinary bibliometric indicators elicited by Scholarometer allow us to implement for the first time a universal impact measure proposed in the literature. Our evaluation suggests that this metric provides an effective means for comparing scholarly impact across disciplinary boundaries.  相似文献   

8.
To understand the biology of the interactome, the covisualization of protein interactions and other protein-related data is required. In this study, we have adapted a 3-D network visualization platform, GEOMI, to allow the coanalysis of protein-protein interaction networks with proteomic parameters such as protein localization, abundance, physicochemical parameters, post-translational modifications, and gene ontology classification. Working with Saccharomyces cerevisiae data, we show that rich and interactive visualizations, constructed from multidimensional orthogonal data, provide insights on the complexity of the interactome and its role in biological processes and the architecture of the cell. We present the first organelle-specific interaction networks, that provide subinteractomes of high biological interest. We further present some of the first views of the interactome built from a new combination of yeast two-hybrid data and stable protein complexes, which are likely to approximate the true workings of stable and transient aspects of the interactome. The GEOMI tool and all interactome data are freely available by contacting the authors.  相似文献   

9.
Combining molecular and morphological evidence, an invasive ant in Missouri and Illinois, USA, is identified as Tetramorium tsushimae Emery, 1925, a polygynous-polycalic species native to East Asia. T. tsushimae is recorded as invasive for the first time. RFLP and worker morphometrics provide tools for reliable determination. Mitochondrial DNA data reveal the probable geographic origin of the invasive populations to be Japan. The first two authors contributed equally to this work.  相似文献   

10.
本文在实际测量数据的基础上,提出一种运用主成分分析的方法对数据进行筛选和匹配,进而对人体和猕猴作典型相关分析,从而得出这种替代是有意义的.  相似文献   

11.
The Protein Data Bank (PDB) is the worldwide repository of 3D structures of proteins, nucleic acids and complex assemblies. The PDB’s large corpus of data (> 100,000 structures) and related citations provide a well-organized and extensive test set for developing and understanding data citation and access metrics. In this paper, we present a systematic investigation of how authors cite PDB as a data repository. We describe a novel metric based on information cascade constructed by exploring the citation network to measure influence between competing works and apply that to analyze different data citation practices to PDB. Based on this new metric, we found that the original publication of RCSB PDB in the year 2000 continues to attract most citations though many follow-up updates were published. None of these follow-up publications by members of the wwPDB organization can compete with the original publication in terms of citations and influence. Meanwhile, authors increasingly choose to use URLs of PDB in the text instead of citing PDB papers, leading to disruption of the growth of the literature citations. A comparison of data usage statistics and paper citations shows that PDB Web access is highly correlated with URL mentions in the text. The results reveal the trend of how authors cite a biomedical data repository and may provide useful insight of how to measure the impact of a data repository.  相似文献   

12.
Two methods of aerobiological collection, the Burkard(Hirst-based) and the Cour, were compared using datafrom pollen collected at Bellaterra (Barcelona, Spain)between 1994 and 1996. Results for three pollen taxaof allergenic relevance (Urticaceae, Poaceae andOlea) are presented. This study confirmed thedifficulty of finding a reliable conversion formulabetween these sampling methods, as has been found byseveral other authors.An alternative statistical analysis was carried outusing categorical data, the pollen concentration databeing first converted into an ordinal scale with fivelevels based on local records. Our analysis shows thatboth methods provide essentially the sameinformation.  相似文献   

13.
A character of special interest in evolutionary studies is usually optimized on a phylogenetic tree, with or without the outgroups employed in that analysis. Both practices are never justified and look like arbitrary choices. Focusing on one example, we draw the conclusion that authors retain or remove outgroups depending on the way these outgroups sample the diversity of states of the character(s) of special interest. The topology without outgroups is often used by authors when different outgroup taxa non‐exhaustively sample the different states of the character of interest outside of the ingroup. This can make the analysis incoherent, because its different steps are not based on the same data matrix (outgroups are removed in the last step). It can provide several incoherent and possibly different patterns for a same character of interest, one issuing from the first step of phylogeny construction and the other resulting from the a posteriori optimization on the truncated topology. Phylogenetic analyses should be designed to minimize this problem, selecting outgroup and ingroup taxa whose diversity of character states is needed for reconstructing the evolutionary history of the character of interest. © The Willi Hennig Society 2004.  相似文献   

14.
The authors provide the data on the effect of emotional painful stress (EPS) of varying duration on the activity of natural killers (NK) of August rats' spleen 1 to 9 days after exposure to stress is discontinued. The activity of NK was tested against target cells K 562 labeled with 51Cr in a 14-hour test. The effect of stress was found to depend on the duration of the stressor reaction. 1 1/2- and 3-hour stress activated NK, while prolonged 6-hour stress suppressed the activity of natural killers within the first 2 days, followed by the recovery by day 7-9 of the activity of lymphocytes having natural cytotoxicity. Tiloron, a synthetic inducer of endogenous interferon, corrected the post-stressor depression of NK activity.  相似文献   

15.
The main aim of this paper, by the authors' intention, was to attempt to study and provide evidence for that routine transabdominal sonography has great capacities in diagnosing small intestinal strangulation and obstruction ileus caused by commissures or tumors. The data of 48 cases of small intestinal ileus (27 of its strangulation form and 21 of its obturation one) were analyzed. The paper details guidelines on ultrasonographic techniques and the ultrasound semiotics of this pathology. It is the first time that the authors give individual methodological and semiotic approaches at sonography in this group of papers. They present a particularly clinical picture in combination with ultrasonographic data by providing their constant comparison, which serves as an additional support of the results of this paper. In the authors' opinion, the findings suggest that transabdominal sonography may be a successful basic diagnostic technique for strangulation and obturation forms of small intestinal ileus.  相似文献   

16.
本文首先阐述了作为我国亚热带地区某些森林植物群落优势种或主要伴生种的木莲(Manglietia fordiana)在我国分布的概况;其次,对以我国亚热带地区特有植物(木莲)为建群种的稀有林型进行了分析。江西木莲林分布于井冈山和官山自然保护区。笔者建议研究以珍稀植物为主要种类的植被类型及其生境条件,为保护这些物种提供原始资料。  相似文献   

17.
Social factors constitute an important component of the environment of many animals and have a profound influence on their physiology and behavior. Studies of social influences on circadian rhythms have been hampered by a methodological trade-off: automatic data acquisition systems obtain high-quality data but are effective only for individually isolated animals and therefore compromise by requiring a context that may not be sociobiologically relevant. Human observers can monitor animal activity in complex social environments but are limited in the resolution and quality of data that can be gathered. The authors developed and validated a method for prolonged, automatic, high-quality monitoring of focal honey bees in a relatively complex social environment and with minimal illumination. The method can be adapted for studies on other animals. The authors show that the system provides a reliable estimation of the actual path of a focal bee, only rarely misses its location for > 1 min, and removes most nonspecific signals from the background. Using this system, the authors provide the first evidence of social influence on the ontogeny of activity rhythms. Young bees that were housed with old foragers show ~24-h rhythms in locomotor activity at a younger age and with stronger rhythms than bees housed with a similar number of young bees. By contrast, the maturation of the hypopharyngeal glands was slower in bees housed with foragers, similar to findings in previous studies. The morphology and function of the hypopharyngeal glands vary along with age-based division of labor. Therefore, these findings indicate that social inhibition of task-related maturation was effective in the experimental setup. This study suggests that although the ontogeny of circadian rhythms is typically correlated with the age-based division of labor, their social regulation is different.  相似文献   

18.
Confirming the literature data the authors describe that the heart rate is smaller in the newborn rats than in adult ones and increases until the adult values during the first two weeks of life. On the other hand, the blood thyroid hormone exhibits the same pattern, showing an early postnatal increment. As, according the Adolph's data (1967), the heart rate enhancement is not due to the catecholamines, the authors suppose that such enhancement might conceivably depend on thyroid hormone increment.  相似文献   

19.
The authors present here mathematical models in which levels of subjective alertness and cognitive throughput are predicted by three components that interact with one another in a nonlinear manner. These components are (1) a homeostatic component (H) that falls in a sigmoidal manner during wake and rises in a saturating exponential manner at a rate that is determined by circadian phase during sleep; (2) a circadian component (C) that is a function of the output of our mathematical model of the effect of light on the circadian pacemaker, with the amplitude further regulated by the level of H; and (3) a sleep inertia component (W) that rises in a saturating exponential manner after waketime. The authors first construct initial models of subjective alertness and cognitive throughput based on the results of sleep inertia studies, sleep deprivation studies initiated across all circadian phases, 28-h forced desynchrony studies, and alertness and performance dose response curves to sleep. These initial models are then refined using data from nearly one hundred fifty 30- to 50-h sleep deprivation studies in which subjects woke at their habitual times. The interactive three-component models presented here are able to predict even the fine details of neurobehavioral data from sleep deprivation studies and, after further validation, may provide a powerful tool for the design of safe shift work and travel schedules, including those in which people are exposed to unusual patterns of light.  相似文献   

20.
The achievement of a robust, effective and responsible form of data sharing is currently regarded as a priority for biological and bio-medical research. Empirical evaluations of data sharing may be regarded as an indispensable first step in the identification of critical aspects and the development of strategies aimed at increasing availability of research data for the scientific community as a whole. Research concerning human genetic variation represents a potential forerunner in the establishment of widespread sharing of primary datasets. However, no specific analysis has been conducted to date in order to ascertain whether the sharing of primary datasets is common-practice in this research field. To this aim, we analyzed a total of 543 mitochondrial and Y chromosomal datasets reported in 508 papers indexed in the Pubmed database from 2008 to 2011. A substantial portion of datasets (21.9%) was found to have been withheld, while neither strong editorial policies nor high impact factor proved to be effective in increasing the sharing rate beyond the current figure of 80.5%. Disaggregating datasets for research fields, we could observe a substantially lower sharing in medical than evolutionary and forensic genetics, more evident for whole mtDNA sequences (15.0% vs 99.6%). The low rate of positive responses to e-mail requests sent to corresponding authors of withheld datasets (28.6%) suggests that sharing should be regarded as a prerequisite for final paper acceptance, while making authors deposit their results in open online databases which provide data quality control seems to provide the best-practice standard. Finally, we estimated that 29.8% to 32.9% of total resources are used to generate withheld datasets, implying that an important portion of research funding does not produce shared knowledge. By making the scientific community and the public aware of this important aspect, we may help popularize a more effective culture of data sharing.  相似文献   

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