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121.
122.
Lower Miocene siliciclastic sediments of the Vöckla Schichten and Atzbacher Sande, Austria, contain a shallow-water trace-fossil assemblage of the Cruziana ichnofacies includingSkolithos isp.,Planolites ? beverleyensis, Ophiomorpha annulata, O.nodosa, Rosselia socialis, Cylindrichnus concentricus, Scolicia isp., andBichordites monastiriensis. The ichnogenusRosselia and the ichnospeciesRosselia socialis are revised. Analysis ofScolicia isp. andB. monastiriensis provides new information about their morphology and ichnotaxonomy. 相似文献
123.
Carles Grau Romuald Ginhoux Alejandro Riera Thanh Lam Nguyen Hubert Chauvat Michel Berg Julià L. Amengual Alvaro Pascual-Leone Giulio Ruffini 《PloS one》2014,9(8)
Human sensory and motor systems provide the natural means for the exchange of information between individuals, and, hence, the basis for human civilization. The recent development of brain-computer interfaces (BCI) has provided an important element for the creation of brain-to-brain communication systems, and precise brain stimulation techniques are now available for the realization of non-invasive computer-brain interfaces (CBI). These technologies, BCI and CBI, can be combined to realize the vision of non-invasive, computer-mediated brain-to-brain (B2B) communication between subjects (hyperinteraction). Here we demonstrate the conscious transmission of information between human brains through the intact scalp and without intervention of motor or peripheral sensory systems. Pseudo-random binary streams encoding words were transmitted between the minds of emitter and receiver subjects separated by great distances, representing the realization of the first human brain-to-brain interface. In a series of experiments, we established internet-mediated B2B communication by combining a BCI based on voluntary motor imagery-controlled electroencephalographic (EEG) changes with a CBI inducing the conscious perception of phosphenes (light flashes) through neuronavigated, robotized transcranial magnetic stimulation (TMS), with special care taken to block sensory (tactile, visual or auditory) cues. Our results provide a critical proof-of-principle demonstration for the development of conscious B2B communication technologies. More fully developed, related implementations will open new research venues in cognitive, social and clinical neuroscience and the scientific study of consciousness. We envision that hyperinteraction technologies will eventually have a profound impact on the social structure of our civilization and raise important ethical issues. 相似文献
124.
Integrated species delimitation and conservation implications of an endangered weevil Pachyrhynchus sonani (Coleoptera: Curculionidae) in Green and Orchid Islands of Taiwan
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YEN‐TING CHEN HUI‐YUN TSENG MING‐LUEN JENG YONG‐CHAO SU WEN‐SAN HUANG CHUNG‐PING LIN 《Systematic Entomology》2017,42(4):796-813
Oceanic islands are productive habitats for generating new species and high endemism, which is primarily due to their geographical isolation, smaller population sizes and local adaptation. However, the short divergence times and subtle morphological or ecological divergence of insular organisms may obscure species identity, so the cryptic endemism on islands may be underestimated. The endangered weevil Pachyrhynchus sonani Kôno (Coleoptera: Curculionidae: Entiminae: Pachyrhynchini) is endemic to Green Island and Orchid Island of the Taiwan‐Luzon Archipelago and displays widespread variation in coloration and host range, thus raising questions regarding its species boundaries and degree of cryptic diversity. We tested the species boundaries of P. sonani using an integrated approach that combined morphological (body size and shape, genital shape, coloration and cuticular scale), genetic (four genes and restriction site‐associated DNA sequencing, RAD‐seq) and ecological (host range and distribution) diversity. The results indicated that all the morphological datasets for male P. sonani, except for the colour spectrum, reveal overlapping but statistically significant differences between islands. In contrast, the morphology of the female P. sonani showed minimum divergence between island populations. The populations of P. sonani on the two islands were significantly different in their host ranges, and the genetic clustering and phylogenies of P. sonani established two valid evolutionary species. Integrated species delimitation combining morphological, molecular and ecological characters supported two distinct species of P. sonani from Green Island and Orchid Island. The Green Island population was described as P. jitanasaius sp.n. Chen & Lin, and it is recommended that its threatened conservation status be recognized. Our findings suggest that the inter‐island speciation of endemic organisms inhabiting both islands may be more common than previously thought, and they highlight the possibility that the cryptic diversity of small oceanic islands may still be largely underestimated. 相似文献
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Peroxisomal membrane proteins (PMPs) from the Swiss-Webster mouse are analyzed and compared to those of rats and humans using sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) and immunoblotting. A purification procedure for fresh mouse, rat, or human biopsy liver which enriches peroxisomal/mitochondrial marker enzyme ratios over 100-fold is characterized. When analyzed by SDS-PAGE, membranes of purified liver peroxisomes are shown to contain the same complement of 145-, 70-, 55-, 36-, and 22-kDa PMPs in rats, mice, and humans. A rabbit polyclonal antibody raised against mouse peroxisomal membranes demonstrates immunoreactivity to 145- and 70-kDa proteins in fresh liver homogenates from all three species and in control or Zellweger syndrome fibroblasts from humans. Human autopsy or placental tissues which were refrigerated before analysis exhibited 105-, 55-, and 36-kDa peptides which may be derived from the 145- and 70-kDa peptides. Such conversions, if related to degradation, may explain difficulties in purifying peroxisomes from human autopsy specimens. Variable amounts of the 55-kDa peptide also occurred in mouse adrenal and lung, and the conversion of higher to lower molecular weight PMPs could not be demonstrated by in vitro incubation of mouse liver. Further definition of the structure and variability of mammalian PMPs should be helpful in understanding polyenzymopathies such as Zellweger syndrome. 相似文献
127.
Xavier Ruiz Lluis Jover Vittorio Pedrocchi Daniel Oro Jacob Gonzlez‐Sols 《Journal of avian biology》2000,31(4):567-575
During the Audouin's Gull's breeding season at the Ebro Delta in 1993, 24 fresh eggs from eight three-egg clutches (modal clutch-size) were collected at the peak of the laying period. Eggs were processed to obtain formalin-fixed yolks, which were halved and stained using the potassium dichromate method. Digitized images of the yolks were examined to assess the daily rates of yolk deposition. We used these data in combination with egg compositional analysis to build a model of energy demands during the formation of an average clutch in Audouin's Gull. To show how the different parameters of clutch formation affect the daily energy investment peak, we performed a simulation analysis in which the rapid yolk development (RYD) period, the follicle triggering interval (FTI), the laying interval (LI) and the albumen synthesis period (ASP) were allowed to vary simultaneously. In our sample, the mean RYD period was seven days with a range from six to eight days. There were no significant differences in yolk volume among eggs in a clutch, but albumen volume was significantly smaller in third eggs. According to our model the albumen synthesis of the a-egg coincides with the energy demand peak for clutch formation. This peak represents an increase by ca. 42% in female energy requirements. Values obtained from the simulation analysis showed that only the ASP of the a-egg and the RYD durations of the second and third follicles produced noticeable reductions in peak energy investment. We predict that in gulls, whose laying intervals seem to be kept constant, significant increases of the durations of the RYD periods of second and third eggs, or even significant reductions of yolk size of these eggs, may operate simultaneously to match the energy demands during clutch formation to the prevailing food conditions. 相似文献
128.
Loïc Pellissier Charlotte Ndiribe Anne Dubuis Jean‐Nicolas Pradervand Nicolas Salamin Antoine Guisan Sergio Rasmann 《Ecology letters》2013,16(5):600-608
Understanding drivers of biodiversity patterns is of prime importance in this era of severe environmental crisis. More diverse plant communities have been postulated to represent a larger functional trait‐space, more likely to sustain a diverse assembly of herbivore species. Here, we expand this hypothesis to integrate environmental, functional and phylogenetic variation of plant communities as factors explaining the diversity of lepidopteran assemblages along elevation gradients in the Swiss Western Alps. According to expectations, we found that the association between butterflies and their host plants is highly phylogenetically structured. Multiple regression analyses showed the combined effect of climate, functional traits and phylogenetic diversity in structuring butterfly communities. Furthermore, we provide the first evidence that plant phylogenetic beta diversity is the major driver explaining butterfly phylogenetic beta diversity. Along ecological gradients, the bottom up control of herbivore diversity is thus driven by phylogenetically structured turnover of plant traits as well as environmental variables. 相似文献
129.