294 research outputs found
MILOPrOductIOn Of vIabLe Miscanthus gigantheus rhIzOMes at fertILe and degraded sOIL
abstract ArAndjelovic, M., G. drAzic, j. MilovAnovic and S. AlekSic, 2014. Miloproduction of viable Miscanthus gigantheus rhizomes at fertile and degraded soil. Bulg. J. Agric. Sci., 20: 1189-1194 expanding supplies of home grown biomass and facilitation of the development and competitiveness of a supply chain in an sustainable manner, presents a core of government's strategy, for energy development in republic of Serbia. Growing agroenergy corps may be one of the solutions according to analysis that were carried out. one of these corps that was found to be especially amenable due to its potentially high productivity and cultivation on degraded terrain is Miscanthus giganteus. The possibility of producing after mentioned plant for the biomass supply chain, at very low cost is the main aim of this study. due to its sterility Miscanthus giganteus can only by propagated by vegetative division. Potential of production of viable rhizome on terrains with different rate of fertility was followed by method of experiments on the field. 6 parameters that were following growth of the rhizome and planting survival rate were monitored. According to the results, main factors that affect production of viable rhizomes are age of mother plants, and biotic effects of weed vegetation. Size of rhizomes and nursery fertilization shoved significantly smaller effect. This study concentrates on available data regarding the potential directions by which Miscanthus material could achieve maximum production, by high density planting
AXES at TRECVID 2012: KIS, INS, and MED
The AXES project participated in the interactive instance search task (INS), the known-item search task (KIS), and the multimedia event detection task (MED) for TRECVid 2012. As in our TRECVid 2011 system, we used nearly identical search systems and user interfaces for both INS and KIS. Our interactive INS and KIS systems focused this year on using classifiers trained at query time with positive examples collected from external search engines. Participants in our KIS experiments were media professionals from the BBC; our INS experiments were carried out by students and researchers at Dublin City University. We performed comparatively well in both experiments. Our best KIS run found 13 of the 25 topics, and our best INS runs outperformed all other submitted runs in terms of P@100. For MED, the system presented was based on a minimal number of low-level descriptors, which we chose to be as large as computationally feasible. These descriptors are aggregated to produce high-dimensional video-level signatures, which are used to train a set of linear classifiers. Our MED system achieved the second-best score of all submitted runs in the main track, and best score in the ad-hoc track, suggesting that a simple system based on state-of-the-art low-level descriptors can give relatively high performance. This paper describes in detail our KIS, INS, and MED systems and the results and findings of our experiments
Chimpanzee identification and social network construction through an online citizen science platform
Abstract Citizen science has grown rapidly in popularity in recent years due to its potential to educate and engage the public while providing a means to address a myriad of scientific questions. However, the rise in popularity of citizen science has also been accompanied by concerns about the quality of data emerging from citizen science research projects. We assessed data quality in the online citizen scientist platform Chimp&See, which hosts camera trap videos of chimpanzees (Pan troglodytes) and other species across Equatorial Africa. In particular, we compared detection and identification of individual chimpanzees by citizen scientists with that of experts with years of experience studying those chimpanzees. We found that citizen scientists typically detected the same number of individual chimpanzees as experts, but assigned far fewer identifications (IDs) to those individuals. Those IDs assigned, however, were nearly always in agreement with the IDs provided by experts. We applied the data sets of citizen scientists and experts by constructing social networks from each. We found that both social networks were relatively robust and shared a similar structure, as well as having positively correlated individual network positions. Our findings demonstrate that, although citizen scientists produced a smaller data set based on fewer confirmed IDs, the data strongly reflect expert classifications and can be used for meaningful assessments of group structure and dynamics. This approach expands opportunities for social research and conservation monitoring in great apes and many other individually identifiable species
Long-term inference of population size and habitat use in a socially dynamic population of wild western lowland gorillas
Genetic estimation of population sizes has been critical for monitoring cryptic and rare species; however, population estimates do not inherently reveal the permanence or stability of the population under study. Thus, it is important to monitor not only the number of individuals in a population, but also how they are associated in groups and how those groups are distributed across the landscape. Adding to the challenge of obtaining such information with high precision for endangered and elusive species is the need for long-term collection of such data. In this study we compare sampling approaches and genotype non-invasive genetic samples to estimate the number and distribution of wild western lowland gorillas occupying a ˘005Ctextasciitildeþinspace100 km2 area in Loango National Park, Gabon, for the periods 2005–2007 and 2014–2017. Based on the number of genotyped individuals we inferred a minimum of 83 gorillas during the first and 81 gorillas during the second study period. We also obtained similar capture–recapture population size estimates for the two periods despite variance in social dynamics like group formations, group dissolutions and individual dispersal. We furthermore found area fidelity for two groups that were sampled for 10–12 years, despite variation in group membership. Our results revealed how individual movements link groups in a `network' and show that western lowland gorilla populations can show a high degree of temporal and geographic stability concurrent with substantial social dynamics
Phosphatidylserine on viable sperm and phagocytic machinery in oocytes regulate mammalian fertilization
Fertilization is essential for species survival. Although Izumo1 and Juno are critical for initial interaction between gametes, additional molecules necessary for sperm: egg fusion on both the sperm and the oocyte remain to be defined. Here, we show that phosphatidylserine (PtdSer) is exposed on the head region of viable and motile sperm, with PtdSer exposure progressively increasing during sperm transit through the epididymis. Functionally, masking phosphatidylserine on sperm via three different approaches inhibits fertilization. On the oocyte, phosphatidylserine recognition receptors BAl1, CD36, Tim-4, and Mer-TK contribute to fertilization. Further, oocytes lacking the cytoplasmic ELMO1, or functional disruption of RAC1 (both of which signal downstream of BAl1/BAl3), also affect sperm entry into oocytes. Intriguingly, mammalian sperm could fuse with skeletal myoblasts, requiring PtdSer on sperm and BAl1/3, ELMO2, RAC1 in myoblasts. Collectively, these data identify phosphatidylserine on viable sperm and PtdSer recognition receptors on oocytes as key players in sperm: egg fusion
AXES at TRECVid 2011
Abstract
The AXES project participated in the interactive known-item search task (KIS) and the interactive instance search task (INS) for TRECVid 2011. We used the same system architecture and a nearly identical user interface for both the KIS and INS tasks. Both systems made use of text search on ASR, visual concept detectors, and visual similarity search. The user experiments were carried out with media professionals and media students at the Netherlands Institute for Sound and Vision, with media professionals performing the KIS task and media students participating in the INS task. This paper describes the results and findings of our experiments
Cost-effective scat-detection dogs: unleashing a powerful new tool for international mammalian conservation biology
Recently, detection dogs have been utilized to collect fecal samples from cryptic and rare mammals. Despite the great promise of this technique for conservation biology, its broader application has been limited by the high cost (tens to hundreds of thousands of dollars) and logistical challenges of employing a scat-detection dog team while conducting international, collaborative research. Through an international collaboration of primatologists and the Chinese Ministry of Public Security, we trained and used a detection dog to find scat from three species of unhabituated, free-ranging primates, for less than $3,000. We collected 137 non-human primate fecal samples that we confirmed by sequencing taxonomically informative genetic markers. Our detection dog team had a 92% accuracy rate, significantly outperforming our human-only team. Our results demonstrate that detection dogs can locate fecal samples from unhabituated primates with variable diets, locomotion, and grouping patterns, despite challenging field conditions. We provide a model for in-country training, while also building local capacity for conservation and genetic monitoring. Unlike previous efforts, our approach will allow for the wide adoption of scat-detection dogs in international conservation biology
The Internal, External and Extended Microbiomes of Hominins
The social structure of primates has recently been shown to influence the composition of their microbiomes. What is less clear is how primate microbiomes might in turn influence their social behavior, either in general or with particular reference to hominins. Here we use a comparative approach to understand how microbiomes of hominins have, or might have, changed since the last common ancestor (LCA) of chimpanzees and humans, roughly six million years ago. We focus on microbiomes associated with social evolution, namely those hosted or influenced by stomachs, intestines, armpits, and food fermentation. In doing so, we highlight the potential influence of microbiomes in hominin evolution while also offering a series of hypotheses and questions with regard to evolution of human stomach acidity, the factors structuring gut microbiomes, the functional consequences of changes in armpit ecology, and whether Homo erectus was engaged in fermentation. We conclude by briefly considering the possibility that hominin social behavior was influenced by prosocial microbes whose fitness was favored by social interactions among individual hominins
The AXES research video search system
We will demonstrate a multimedia content information retrieval engine developed for audiovisual digital libraries targeted at academic researchers and journalists. It is the second of three multimedia IR systems being developed by the AXES project1. The system brings together traditional text IR and state-of-the-art content indexing and retrieval technologies to allow users to search and browse digital libraries in novel ways. Key features include: metadata and ASR search and filtering, on-the-fly visual concept classification (categories, faces, places, and logos), and similarity search (instances and faces)
Geographically structured genomic diversity of non-human primate-infecting Treponema pallidum subsp. pertenue
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