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Sample records for european cave bears

  1. Predormancy omnivory in European cave bears evidenced by a dental microwear analysis of Ursus spelaeus from Goyet, Belgium

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    Peigné, Stéphane; Goillot, Cyrielle; Germonpré, Mietje; Blondel, Cécile; Bignon, Olivier; Merceron, Gildas

    2009-01-01

    Previous morphological and isotopic studies indicate that Late Pleistocene cave bear (Ursus spelaeus) diet ranged from mostly vegetarian to omnivory or even carnivory. However, such analyses do not provide information on seasonal diets, and only provide an average record of diet. A dental microwear analysis of 43 young and adult individuals demonstrate that, during the predormancy period, cave bears from Goyet (Late Pleistocene, Belgium) were not strictly herbivorous, but had a mixed diet composed of hard items (e.g., possibly bone), invertebrates (e.g., insects), meat (ungulates, small vertebrates), and/or plant matter (hard mast, seeds, herbaceous vegetations, and fruits). Therefore, our results indicate that cave bears at Goyet were generalist omnivores during the predormancy period, which is consistent with current data on the dietary ecology of extant bears during this season. These data also raise questions about the ecological role and causes of the extinction of cave bears. PMID:19706401

  2. Dietary ecology of the extinct cave bear: Evidence of omnivory as inferred from dental microwear textures

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    D. Brent Jones; Larisa R.G. DeSantis

    2016-01-01

    The diet of the extinct European cave bear, Ursus spelaeus, has widely been debated. Diverging from the extant brown bear (Ursus arctos) approximately 1.2 million years ago, the cave bear is one of the most ubiquitous fossil bears occurring in Europe during the middle and Late Pleistocene. Early morphological studies suggested that the cave bear was likely specialized on processing tough and/or abrasive foods, while later two-dimensional low-magnification microwear studies suggested that they...

  3. Genomic sequencing of Pleistocene cave bears

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    Noonan, James P.; Hofreiter, Michael; Smith, Doug; Priest, JamesR.; Rohland, Nadin; Rabeder, Gernot; Krause, Johannes; Detter, J. Chris; Paabo, Svante; Rubin, Edward M.

    2005-04-01

    Despite the information content of genomic DNA, ancient DNA studies to date have largely been limited to amplification of mitochondrial DNA due to technical hurdles such as contamination and degradation of ancient DNAs. In this study, we describe two metagenomic libraries constructed using unamplified DNA extracted from the bones of two 40,000-year-old extinct cave bears. Analysis of {approx}1 Mb of sequence from each library showed that, despite significant microbial contamination, 5.8 percent and 1.1 percent of clones in the libraries contain cave bear inserts, yielding 26,861 bp of cave bear genome sequence. Alignment of this sequence to the dog genome, the closest sequenced genome to cave bear in terms of evolutionary distance, revealed roughly the expected ratio of cave bear exons, repeats and conserved noncoding sequences. Only 0.04 percent of all clones sequenced were derived from contamination with modern human DNA. Comparison of cave bear with orthologous sequences from several modern bear species revealed the evolutionary relationship of these lineages. Using the metagenomic approach described here, we have recovered substantial quantities of mammalian genomic sequence more than twice as old as any previously reported, establishing the feasibility of ancient DNA genomic sequencing programs.

  4. Spotted hyena and steppe lion predation behaviours on cave bears of Europe - ?Late Quaternary cave bear extinction as result of predator stress

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    Diedrich, Cajus G.

    2010-05-01

    Cave bears hibernated in caves all over Eurasia (e.g. Rabeder et al., 2000) including alpine regions using mainly larger caves for this purpose. Late Quaternary spotted hyenas Crocuta crocuta spelaea instead occupied mainly areas close to the cave entrances as their dens (Diedrich and Žák 2006, Diedrich 2010). The largest predator, the steppe lion Panthera leo spelaea was only a sporadic cave dweller (Diedrich 2007b, 2009b). His presence and its remains from caves all over Europe can be recently explained best as result of imported carcasses after killing by their largest antagonists, the Late Quaternary spotted hyenas. In some cases the kill might have happened in the hyena den cave itself during the theft of prey remains by lions (Diedrich 2009a). Another reason of their remains in caves of Europe is the hunting onto the herbivorous cave bears, especially during hibernation times, when megafauna prey was less available in the open environments (Diedrich 2009c). These lion remains from caves of Europe, nearly all of which were from adult animals, provide evidence of active predation by lions onto cave bears even in medium high alpine regions (Diedrich 2009b, in review). Lion skeletons in European cave bear dens were therefore often found amongst originally articulated cave bear skeletons or scattered cave bear remains and even close to their hibernation nests (Diedrich et al. 2009c, in review). Not only lions fed on cave bears documented mainly by the large quantities of chewed, punctured and crushed cave bear long-bones; even damaged skulls reveal that hyenas scavenged primarily on cave bear carcasses which were mainly responsible for the destruction of their carcasses and bones (Diedrich 2005, 2009d). Predation and scavenging on cave bears by the two largest Late Quaternary predators C. c. spelaea and P. l. spelaea explains well the large quantity of fragmented cave bear bones over all European caves in low to medium high mountainous elevations, whereas in

  5. Dietary ecology of the extinct cave bear: Evidence of omnivory as inferred from dental microwear textures

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    D. Brent Jones

    2016-12-01

    Full Text Available The diet of the extinct European cave bear, Ursus spelaeus, has widely been debated. Diverging from the extant brown bear (Ursus arctos approximately 1.2 million years ago, the cave bear is one of the most ubiquitous fossil bears occurring in Europe during the middle and Late Pleistocene. Early morphological studies suggested that the cave bear was likely specialized on processing tough and/or abrasive foods, while later two-dimensional low-magnification microwear studies suggested that they were omnivorous and may have consumed more bone than U. arctos. Here, we used dental microwear texture analysis (DMTA to further interpret the diet of the cave bear. Microscopic wear features were assessed and compared to modern ursids, including the cave bears’ closest living relative, U. arctos. Results suggest that U. spelaeus consumed a diet with a diversity of textural properties, similar to most other bears and only distinguishable from the hyper-carnivorous polar bear (Ursus maritimus. Further, only U. maritimus can be distinguished from all bear species here examined (i.e., the giant panda bear, Ailuropoda melanoleuca; sun-bear, Ursus malayanus; spectacled bear, Tremarctos ornatus; American black bear, Ursus americanus; and U. arctos, with significantly greater area-scale fractal complexity (Asfc of microwear surfaces. The DMTA of A. melanoleuca also has significantly lower Asfc than T. ornatus and U. americanus, consistent with observed dietary behavior. As modern bears vary their diets seasonally and across their range, it may be difficult to characterize the dietary ecology of extinct bears using dental microwear alone. Nevertheless, DMTA here demonstrates that U. spelaeus had a diet distinct from the hyper-carnivorous U. maritimus and instead likely consumed food with textural properties most similar to other herbivorous/omnivorous bears. Lastly, the European cave bear and North American giant short-faced bear (Arctodus simus may have had

  6. Ancient DNA reveals differences in behaviour and sociality between brown bears and extinct cave bears.

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    Fortes, Gloria G; Grandal-d'Anglade, Aurora; Kolbe, Ben; Fernandes, Daniel; Meleg, Ioana N; García-Vázquez, Ana; Pinto-Llona, Ana C; Constantin, Silviu; de Torres, Trino J; Ortiz, Jose E; Frischauf, Christine; Rabeder, Gernot; Hofreiter, Michael; Barlow, Axel

    2016-10-01

    Ancient DNA studies have revolutionized the study of extinct species and populations, providing insights on phylogeny, phylogeography, admixture and demographic history. However, inferences on behaviour and sociality have been far less frequent. Here, we investigate the complete mitochondrial genomes of extinct Late Pleistocene cave bears and middle Holocene brown bears that each inhabited multiple geographically proximate caves in northern Spain. In cave bears, we find that, although most caves were occupied simultaneously, each cave almost exclusively contains a unique lineage of closely related haplotypes. This remarkable pattern suggests extreme fidelity to their birth site in cave bears, best described as homing behaviour, and that cave bears formed stable maternal social groups at least for hibernation. In contrast, brown bears do not show any strong association of mitochondrial lineage and cave, suggesting that these two closely related species differed in aspects of their behaviour and sociality. This difference is likely to have contributed to cave bear extinction, which occurred at a time in which competition for caves between bears and humans was likely intense and the ability to rapidly colonize new hibernation sites would have been crucial for the survival of a species so dependent on caves for hibernation as cave bears. Our study demonstrates the potential of ancient DNA to uncover patterns of behaviour and sociality in ancient species and populations, even those that went extinct many tens of thousands of years ago. © 2016 John Wiley & Sons Ltd.

  7. Simulated oxygen isotopes in cave drip water and speleothem calcite in European caves

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    A. Wackerbarth

    2012-11-01

    Full Text Available Interpreting stable oxygen isotope (δ18O records from stalagmites is still one of the complex tasks in speleothem research. Here, we present a novel model-based approach, where we force a model describing the processes and modifications of δ18O from rain water to speleothem calcite (Oxygen isotope Drip water and Stalagmite Model – ODSM with the results of a state-of-the-art atmospheric general circulation model enhanced by explicit isotope diagnostics (ECHAM5-wiso. The approach is neither climate nor cave-specific and allows an integrated assessment of the influence of different varying climate variables, e.g. temperature and precipitation amount, on the isotopic composition of drip water and speleothem calcite.

    First, we apply and evaluate this new approach under present-day climate conditions using observational data from seven caves from different geographical regions in Europe. Each of these caves provides measured δ18O values of drip water and speleothem calcite to which we compare our simulated isotope values. For six of the seven caves modeled δ18O values of drip water and speleothem calcite are in good agreement with observed values. The mismatch of the remaining caves might be caused by the complexity of the cave system, beyond the parameterizations included in our cave model.

    We then examine the response of the cave system to mid-Holocene (6000 yr before present, 6 ka climate conditions by forcing the ODSM with ECHAM5-wiso results from 6 ka simulations. For a set of twelve European caves, we compare the modeled mid-Holocene-to-modern difference in speleothem calcite δ18O to available measurements. We show that the general European changes are simulated well. However, local discrepancies are found, and might be explained either by a too low model resolution, complex local soil-atmosphere interactions affecting evapotranspiration or by cave specific factors

  8. Pitfalls in comparing modern hair and fossil bone collagen C and N isotopic data to reconstruct ancient diets: a case study with cave bears (Ursus spelaeus).

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    Bocherens, Hervé; Grandal-d'Anglade, Aurora; Hobson, Keith A

    2014-01-01

    Stable isotope analyses provide one of the few means to evaluate diet of extinct taxa. However, interpreting isotope data from bone collagen of extinct animals based on isotopic patterns in different tissues of modern animal proxies is precarious. For example, three corrections are needed before making comparisons of recent hair and ancient bone collagen: calibration of carbon-13 variations in atmospheric CO2, different isotopic discrimination between diet-hair keratin and diet-bone collagen, and time averaging of bone collagen versus short-term record in hair keratin. Recently, Robu et al. [Isotopic evidence for dietary flexibility among European Late Pleistocene cave bears (Ursus spelaeus). Can J Zool. 2013;91:227-234] published an article comparing extant carbon (δ(13)C) and nitrogen (δ(15)N) stable isotopic data of European cave bear bone collagen with those of Yellowstone Park grizzly bear hair in order to test the prevailing assumption of a largely vegetarian diet among cave bears. The authors concluded that cave bears were carnivores. This work is unfortunately unfounded as the authors failed to consider the necessary corrections listed above. When these corrections are applied to the Romanian cave bears, these individuals can be then interpreted without involving consumption of high trophic-level food, and environmental changes are probably the reason for the unusual isotopic composition of these cave bears in comparison with other European cave bears, rather than a change of diet. We caution researchers to pay careful attention to these factors when interpreting feeding ecology of extinct fauna using stable isotope techniques.

  9. Late quaternary brown bear (Ursidae: Ursus cf. arctos) from a cave in the Huachuca Mountains, Arizona

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    Nicholas J. Czaplewski; Steve Willsey

    2013-01-01

    In 2008, Steve Willsey discovered the fragmentary cranium of a bear loose on the floor of a cave at about 2270 m elevation near the crest of the Huachuca Mountains. In 2009, we revisited the cave to examine the specimen with the intention of identifying the species. We photographed and measured the main pieces and left them in the cave. The skull is from an adult,...

  10. Low regional diversity of late cave bears mitochondrial DNA at the time of Chauvet Aurignacian paintings

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    Bon, Celine; Berthonaud, Veronique; Fosse, Philippe; Gely, Bernard; Maksud, Frederic; Vitalis, Renaud; Philippe, Michel; van der Plicht, Johannes; Elalouf, Jean-Marc

    The Chauvet-Pont d'Arc and Deux-Ouvertures caves, located along the Ardeche River (France), contain abundant remains of the extinct cave bear (Ursus spelaeus). Because they also display a variety of Palaeolithic anthropogenic evidences, such as the earliest charcoal drawings recorded to date

  11. Complete mitochondrial genome sequence of a Middle Pleistocene cave bear reconstructed from ultrashort DNA fragments.

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    Dabney, Jesse; Knapp, Michael; Glocke, Isabelle; Gansauge, Marie-Theres; Weihmann, Antje; Nickel, Birgit; Valdiosera, Cristina; García, Nuria; Pääbo, Svante; Arsuaga, Juan-Luis; Meyer, Matthias

    2013-09-24

    Although an inverse relationship is expected in ancient DNA samples between the number of surviving DNA fragments and their length, ancient DNA sequencing libraries are strikingly deficient in molecules shorter than 40 bp. We find that a loss of short molecules can occur during DNA extraction and present an improved silica-based extraction protocol that enables their efficient retrieval. In combination with single-stranded DNA library preparation, this method enabled us to reconstruct the mitochondrial genome sequence from a Middle Pleistocene cave bear (Ursus deningeri) bone excavated at Sima de los Huesos in the Sierra de Atapuerca, Spain. Phylogenetic reconstructions indicate that the U. deningeri sequence forms an early diverging sister lineage to all Western European Late Pleistocene cave bears. Our results prove that authentic ancient DNA can be preserved for hundreds of thousand years outside of permafrost. Moreover, the techniques presented enable the retrieval of phylogenetically informative sequences from samples in which virtually all DNA is diminished to fragments shorter than 50 bp.

  12. The effect of body size evolution and ecology on encephalization in cave bears and extant relatives.

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    Veitschegger, Kristof

    2017-06-05

    The evolution of larger brain volumes relative to body size in Mammalia is the subject of an extensive amount of research. Early on palaeontologists were interested in the brain of cave bears, Ursus spelaeus, and described its morphology and size. However, until now, it was not possible to compare the absolute or relative brain size in a phylogenetic context due to the lack of an established phylogeny, comparative material, and phylogenetic comparative methods. In recent years, many tools for comparing traits within phylogenies were developed and the phylogenetic position of cave bears was resolved based on nuclear as well as mtDNA. Cave bears exhibit significantly lower encephalization compared to their contemporary relatives and intraspecific brain mass variation remained rather small. Encephalization was correlated with the combined dormancy-diet score. Body size evolution was a main driver in the degree of encephalization in cave bears as it increased in a much higher pace than brain size. In Ursus spelaeus, brain and body size increase over time albeit differently paced. This rate pattern is different in the highest encephalized bear species within the dataset, Ursus malayanus. The brain size in this species increased while body size heavily decreased compared to its ancestral stage. Early on in the evolution of cave bears encephalization decreased making it one of the least encephalized bear species compared to extant and extinct members of Ursidae. The results give reason to suspect that as herbivorous animals, cave bears might have exhibited a physiological buffer strategy to survive the strong seasonality of their environment. Thus, brain size was probably affected by the negative trade-off with adipose tissue as well as diet. The decrease of relative brain size in the herbivorous Ursus spelaeus is the result of a considerable increase in body size possibly in combination with environmental conditions forcing them to rest during winters.

  13. Late Pleistocene leopards across Europe - northernmost European German population, highest elevated records in the Swiss Alps, complete skeletons in the Bosnia Herzegowina Dinarids and comparison to the Ice Age cave art

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    Diedrich, Cajus G.

    2013-09-01

    European leopard sites in Europe demonstrate Early/Middle Pleistocene out of Africa lowland, and Late Pleistocene Asian alpine migrations being driven by climatic changes. Four different European Pleistocene subspecies are known. The final European Late Pleistocene “Ice Age leopard” Panthera pardus spelaea (Bächler, 1936) is validated taxonomically. The skull shows heavy signs of sexual dimorphism with closest cranial characters to the Caucasian Panthera pardus ciscaucasica (Persian leopard). Late Pleistocene leopards were distributed northernmost, up to S-England with the youngest stratigraphic records by skeletons and cave art in the MIS 2/3 (about 32,000-26,000 BP). The oldest leopard painting left by Late Palaeolithics (Aurignacians/Gravettians) in the Chauvet Cave (S-France) allows the reconstruction of the Ice Age leopard fur spot pattern being close to the snow or Caucasian leopards. The last Ice Age glacial leopard habitat was the mountain/alpine boreal forest (not mammoth steppe lowland), where those hunted even larger prey such as alpine game (Ibex, Chamois). Into some lairs, those imported their prey by short-term cave dwelling (e.g. Baumann's Cave, Harz Mountains, Germany). Only Eurasian Ice Age leopards specialized, similar as other Late Pleistocene large felids (steppe lions), on cave bear predation/scavenging partly very deep in caves. In Vjetrenica Cave (Dinarid Mountains, Bosnia Herzegovina), four adult leopards (two males/two females) of the MIS 3 were found about two km deep from the entrance in a cave bear den, near to one cave bear skeleton, that remained articulated in its nest. Leopards died there, partly being trapped by raising water levels of an active ponor stream, but seem to have been killed possibly either, similar as for lions known, in battles with cave bears in several cave bear den sites of Europe (e.g. Baumann's Cave, Wildkirchli Cave, Vjetrenica Cave). At other large cave sites, with overlap of hyena, wolf and dhole dens at

  14. Hominin-bearing caves and landscape dynamics in the Cradle of Humankind, South Africa

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    Dirks, Paul H. G. M.; Berger, Lee R.

    2013-02-01

    sediment traps on the landscape. Caves in the CoH are distributed along lithological boundaries and NNE and ESE fractures. Fossil-bearing caves have a distinct distribution pattern, with different directional controls, a high degree of clustering, a characteristic spacing of 1700 m or 3400 m, and a characteristic bi-model fractal distribution best explained by a combination of geological and biological controls. It is suggested that clustering of fossil-bearing caves reflects a Lévy flight patterns typical for foraging behavior in animals. The controlling element in this behavior could have been availability of water in or near groups of caves, resulting in preferential occupation of these caves with accumulation of diverse faunal fossil assemblages. The tectonic drivers shaping the dynamic landscape of the CoH did not involve large, seismically active fault lines, but complex interactions between multiple smaller fractures and joints activated in a far field stress controlled by uplift. The landscape of the CoH, with its caves and water sources and dissected landscape provided a setting favored by many animals including hominins. A modern day analog for what the CoH would have looked like 2 My ago is found 50 km east of Johannesburg, near the SE margin of the Johannesburg Dome.

  15. An early Brunhes (age for the Lower Paleolithic tool-bearing Kozarnika cave sediments, Bulgaria

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    Muttoni, Giovanni; Sirakov, Nikolas; Guadelli, Jean-Luc; Kent, Dennis V.; Scardia, Giancarlo; Monesi, Edoardo; Zerboni, Andrea; Ferrara, Enzo

    2017-12-01

    We present a new sedimentological profile and a magnetostratigraphy of the tool-bearing Kozarnika cave sediments from Bulgaria. Modal analysis of cave infilling sedimentary texture indicates that the tool-bearing layers contain a sizable fraction of sediment interpreted as loess. We also find evidence for a relatively thick and well defined normal magnetic polarity in the upper-middle part of the section interpreted as a record of the Brunhes Chron, followed down-section by reverse polarity directions interpreted as a record of the Matuyama Chron. The lowermost levels with Lower Paleolithic tools (Layers 13a-c) lie in the early Brunhes at a nominal maximum age of ∼0.75 Ma, while the Brunhes-Matuyama boundary (0.78 Ma) falls in Layer 13 Lower immediately below. This finding represents a conspicuous revision of previous age estimates for the same tool-bearing layers.

  16. Križna jama (SW Slovenia): Numerical- and correlated-ages from cave bear-bearing sediments

    Czech Academy of Sciences Publication Activity Database

    Bosák, Pavel; Pruner, Petr; Zupan Hajna, N.; Hercman, H.; Mihevc, A.; Wagner, Jan

    2010-01-01

    Roč. 39, č. 3 (2010), s. 529-549 ISSN 0583-6050 R&D Projects: GA AV ČR IAA300130701 Institutional research plan: CEZ:AV0Z30130516 Keywords : magnetostratigraphy * U-series dating * bear cave * Middle/late Pleistocene Subject RIV: DB - Geology ; Mineralogy Impact factor: 0.750, year: 2010 http://carsologica.zrc-sazu.si/downloads/393/Bosak.pdf

  17. On the palaeobiology of the extinct cave bear Ursus spelaeus ROSENMÜLLER. Insights from stable isotope analysis

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    Grandal-D'Anglade, Aurora; Pérez-Rama, Marta; Fernández-Mosquera, Daniel

    2010-05-01

    Isotopic signatures (δ13C, δ15N) of bone collagen are used more and more to obtain the paleobiological data of fossil species. By means of these signatures, for example, the diet type of an extint species may be inferred. Also, the climate in which this species developed may greatly influence on the isotopic signature of its bone collagen. This influence is firstly produced in the initial material of the trophic chain but also may produce variations due to physiological changes caused by climatic changes in the species involved in this trophic chain. The cave bear (Ursus spelaeus ROSENMÜLLER) is a species of broad distribution in the European Pleistocene sites that has been studied from the isotopic point of view, trying to establish its diet type. For the moment, the results vary: though in most cases the isotopic values indicate a preferably herbivore diet type, differences exist between sites of different geographic zones and chronologies. Taking into account that climate influences on the cave bear's physiology through the physiological mechanism of hibernation, it is expected that in bears that lived in different climatic phases, the isotopic signatures will be also different. During hibernation a recycling of nitrogenised compounds is produced for protein synthesis, including bone collagen, so it is expected that the isotopic signature, at least of Nitrogen, will be altered with respect to the synthesized collagen when the bear is active and feeds normally. However, it is difficult to establish up to what extent the isotopic signatures due to hibernation or diet are overlapped. To study the physiological effect of hibernation on isotopic signatures we have selected bone remains of cave bears from populations whose chronologies correspond to different climatic moments, and in different ontogenetic stages, coming from Galician caves (NW of the Iberian Peninsula). Adult individuals show different isotopic signatures depending on their chronology. Juvenile

  18. Stratigraphy, U-Th chronology, and paleoenvironments at Gladysvale Cave: insights into the climatic control of South African hominin-bearing cave deposits.

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    Pickering, Robyn; Hancox, Phillip J; Lee-Thorp, Julia A; Grün, Rainer; Mortimer, Graham E; McCulloch, Malcolm; Berger, Lee R

    2007-11-01

    Gladysvale Cave is one of the few Plio-Pleistocene hominin-bearing cave sites in South Africa that contains a well-stratified cave fill with clastic sediments interspersed with flowstones. The clastic sediments can be divided into units based on the presence of intercalated flowstones, forming flowstone bounded units (FBU). Ten MC-ICP-MS uranium-series dates on several flowstone horizons in the Gladysvale Internal Deposit fan indicate deposition from the late mid-Pleistocene ( approximately 570 ka) to Holocene ( approximately 7 ka) during limited periods of higher effective moisture. Clastic sedimentation occurred during the interceding, presumably more arid, periods. This sequence is not consistent with earlier models for South African caves that simply assumed interglacial sedimentation and glacial erosion. (13)C/(12)C data suggest that flowstone tended to form during periods with higher proportions of C(3) plants in the local vegetation, while clastic sediments reflect higher proportions of C(4) grasses, although this is not always the case. We argue that flowstones are precipitated during periods of higher effective precipitation and restricted cave entrances, while clastic sediments accumulated during periods with more open vegetation. The sedimentary fill of the fossiliferous deposits are, therefore, highly episodic in nature, with large periods of time unlikely to be represented. This has serious implications for the other hominin-bearing caves close by, as these deposits are likely to be similarly episodic. This is especially pertinent when addressing extinction events and reconstructions of paleoenvironments, as large periods of time may be unrecorded. The Gladysvale Cave fill sediments may serve as a climatically forced chronostratigraphic model for these less well-stratified and well-dated Plio-Pleistocene sites.

  19. NEW LOCALITY OF CAVE BEAR (Ursus spelaeus Rosenmüller & Heinroth, 1794 IN BOSNIA AND HERZEGOVINA: MORPHO- ANATOMICAL CHARACTERISTICS OF CRANIAL SKELETON FOUND IN CAVE AT VRELO MOKRANJSKA MILJACKA

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    Lada Lukić-Bilela

    2013-10-01

    Full Text Available During the investigation of the Cave at Vrelo Mokranjska Miljacka, the bone remains of the cave bear (Ursus spelaeus Rosenmüller & Heinroth, 1794 was found. This is the new Pleistocene fauna locality of this extinct species in Bosnia and Herzegovina. Almost complete cranial skeleton belongs to a young adult male. Analyzed morphometric proportions completely fit within the variation range of the Pleistocene cave bear populations in Bosnia and Herzegovina.Key words: Ursus spelaeus, skull, teeth, Cave of Vrelo Mokranjska Miljacka

  20. Contemporary flowstone development links early hominin bearing cave deposits in South Africa

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    Pickering, Robyn; Kramers, Jan D.; Hancox, Philip John; de Ruiter, Darryl J.; Woodhead, Jon D.

    2011-06-01

    The Cradle of Humankind cave sites in South Africa preserve fossil evidence of four early hominin taxa: Australopithecus africanus, Australopithecus sediba, Paranthropus robustus and early Homo. In order to integrate this record into a pan-African scenario of human evolutionary history it is critical to have reliable dates and temporal ranges for the southern African hominins. In the past a lack of precise and accurate chronological data has prevented the evaluation of the temporal relationships between the various sites. Here we report new uranium-lead (U-Pb) radiometric ages obtained from sheets of calcium carbonate flowstone inter-bedded between clastic cave sediments at the site of Swartkrans, providing bracketing ages for the fossiliferous deposits. The fossil bearing units of Swartkrans, specifically the Hanging Remnant and Lower Bank of Member 1, are underlain by flowstone layers dated to 2.25 ± 0.05 Ma and 2.25 ± 0.08 Ma and capped by layers of 1.8 ± 0.01 Ma and 1.7 ± 0.07 Ma. The age bracket of the Member 1 deposits is therefore between 2.31 and 1.64 Ma. However, by combining the U-Pb with biostratigraphic data we suggest that this can be narrowed down to between 1.9 and 1.8 Ma. These data can be compared with other recently dated sites and a radiometrically dated U-Pb age sequence formed: Sterkfontein Member 4, Swartkrans Member 1, Malapa, and Cooper's D. From this new U-Pb dataset, a pattern of contemporary flowstone development emerges, with different caves recording the same flowstone-forming event. Specifically overlapping flowstone formation takes place at Swartkrans and Sterkfontein at ~ 2.29 Ma and ~ 1.77 Ma, and at Sterkfontein and Malapa at ˜ 2.02 Ma. This suggests a regional control over the nature and timing of speleothem development in cave deposits and these flowstone layers could assist in future correlation, both internal to specific deposits and regionally between sites.

  1. Cave bear (Ursus spelaeus Rosenmüller & Heinroth males' den from Velika Pećina in Duboka Near Kučevo, Eastern Serbia

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    Dimitrijević Vesna M.

    2002-01-01

    Full Text Available More a 100 years after the first research in the cave Velika pećina in Duboka near Kučevo cave bear remains were discovered in a small chamber cut off from the passable channels by a 7 m high slope. A whole skull, bones of a forearm in articulation, and other skeleton parts were laying on the cave floor encrusted in travertine cover and in some places overgrown by stalagmites. Bones belonged to adult males, which found there the shelter to hibernate, in a short epizode that ended by closing the channels that once linked this part of the cave to a surface.

  2. THE MOLLUSCAN FAUNA FROM THE UPPER PLEISTOCENE VERTEBRATE-BEARING DEPOSITS OF S. TEODORO CAVE (NORTH-EASTERN SICILY

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    DANIELA ESU

    2007-03-01

    Full Text Available This paper deals with terrestrial, freshwater and marine molluscs collected in the upper Pleistocene deposits of clay, sands and gravels of S. Teodoro Cave (North-eastern Sicily. Beginning from 1998 two trenches have been excavated (1998 and 2002-2004. A highly diversified assemblage of endemic and not endemic vertebrates (elephant, horse, wild ox, deer, wild boar, hyaena, fox, mouse, ground vole, shrew, hedgehog, bats, birds, reptiles, invertebrates (molluscs and vegetal remains have been collected from the two trenches. The molluscan fauna is represented by poor to rich-species assemblages of land and freshwater gastropods and bivalves with Mediterranean-European character. Some species have been found for the first time as fossils in Sicily. The land snails prevail in the 1998 trench showing a persistent arid environment during the time of the sediment deposition. The freshwater species, characteristic of slow-running water, point to the presence of a small water body (stream or spring inside the cave, probably more consistent in the 2002-2004 trench where this fauna prevails. The dispersal of the molluscan fauna of S. Teodoro Cave from the mainland during the low stand sea-level phases of the upper Pleistocene probably belongs to the same dispersal events following the Oxygen Isotope Stage 5e which introduced into the island not endemic faunal elements which are associated with endemic faunal elements in S. Teodoro Cave. Littoral marine reworked molluscs found in the cave deposits probably come from the sedimentary cover of a middle Pleistocene terrace which overlies the roof of the cave. SHORT NOTE

  3. Seasonality of use of Za Hájovnou Cave by bears and lions

    Czech Academy of Sciences Publication Activity Database

    Nývltová Fišáková, Miriam

    2014-01-01

    Roč. 70, 1-2 (2014), s. 103-106 ISSN 0036-5343 Institutional support: RVO:68081758 Keywords : Middle Pleistocene * thin sections * seasonality * caves * the Czech Republic Subject RIV: AC - Archeology, Anthropology, Ethnology

  4. Growth trajectories in the cave bear and its extant relatives: an examination of ontogenetic patterns in phylogeny.

    Science.gov (United States)

    Fuchs, Manuela; Geiger, Madeleine; Stange, Madlen; Sánchez-Villagra, Marcelo R

    2015-11-02

    The study of postnatal ontogeny can provide insights into evolution by offering an understanding of how growth trajectories have evolved resulting in adult morphological disparity. The Ursus lineage is a good subject for studying cranial and mandibular shape and size variation in relation to postnatal ontogeny and phylogeny because it is at the same time not diverse but the species exhibit different feeding ecologies. Cranial and mandibular shapes of Ursus arctos (brown bear), U. maritimus (polar bear), U. americanus (American black bear), and the extinct U. spelaeus (cave bear) were examined, using a three-dimensional geometric morphometric approach. Additionally, ontogenetic series of crania and mandibles of U. arctos and U. spelaeus ranging from newborns to senile age were sampled. The distribution of specimens in morphospace allowed to distinguish species and age classes and the ontogenetic trajectories U. arctos and U. spelaeus were found to be more similar than expected by chance. Cranial shape changes during ontogeny are largely size related whereas the evolution of cranial shape disparity in this clade appears to be more influenced by dietary adaptation than by size and phylogeny. The different feeding ecologies are reflected in different cranial and mandibular shapes among species. The cranial and mandibular shape disparity in the Ursus lineage appears to be more influenced by adaptation to diet than by size or phylogeny. In contrast, the cranial and mandibular shape changes during postnatal ontogeny in U. arctos and U. spelaeus are probably largely size related. The patterns of morphospace occupation of the cranium and the mandible in adults and through ontogeny are different.

  5. Ontogenetic convergence and evolution of foot morphology in European cave salamanders (Family: Plethodontidae

    Directory of Open Access Journals (Sweden)

    Nistri Annamaria

    2010-07-01

    Full Text Available Abstract Background A major goal in evolutionary biology is to understand the evolution of phenotypic diversity. Both natural and sexual selection play a large role in generating phenotypic adaptations, with biomechanical requirements and developmental mechanisms mediating patterns of phenotypic evolution. For many traits, the relative importance of selective and developmental components remains understudied. Results We investigated ontogenetic trajectories of foot morphology in the eight species of European plethodontid cave salamander to test the hypothesis that adult foot morphology was adapted for climbing. Using geometric morphometrics and other approaches, we found that developmental patterns in five species displayed little morphological change during growth (isometry, where the extensive interdigital webbing in adults was best explained as the retention of the juvenile morphological state. By contrast, three species exhibited significant allometry, with an increase in interdigital webbing during growth. Phylogenetic analyses revealed that multiple evolutionary transitions between isometry and allometry of foot webbing have occurred in this lineage. Allometric parameters of foot growth were most similar to those of a tropical species previously shown to be adapted for climbing. Finally, interspecific variation in adult foot morphology was significantly reduced as compared to variation among juveniles, indicating that ontogenetic convergence had resulted in a common adult foot morphology across species. Conclusions The results presented here provide evidence of a complex history of phenotypic evolution in this clade. The common adult phenotype exhibited among species reveals that selection plays an important part in generating patterns of foot diversity in the group. However, developmental trajectories arriving at this common morphology are distinct; with some species displaying developmental stasis (isometry, while others show an increase

  6. Heavy Metals in Brown Bears from the Central European Carpathians

    Directory of Open Access Journals (Sweden)

    O. Čelechovská

    2006-01-01

    Full Text Available The aim of the present study was to assess heavy metal load in the brown bear (Ursus arctos living in the central European Carpathians. Between 2002 and 2004, fifteen bears were examined to evaluate the distribution of cadmium, lead, mercury and copper in the animals' muscles (diaphragm, spleen, liver and kidney. The highest content of cadmium, lead and mercury was found in the kidney (17.4 ± 5.2 mg kg-1, 1.16 ± 0.39 mg kg-1, 0.39 ± 0.25 mg kg-1, whereas the lowest content of the metals was observed in the muscles (0.017 ± 0.009 mg kg-1, 0.299 ± 0.308 mg kg-1, 0.013 ± 0.011 mg kg-1. Second highest concentration of cadmium, lead and mercury was detected in the liver (0.83 ± 0.24 mg kg-1, 0.99 ± 0.61 mg kg-1, 0.11 ± 0.05 mg kg-1. Copper distributions and concentrations in bear tissues were as follows (in descending order: liver (23.9 ± 6.7 mg kg-1, > kidneys (9.0 ± 3.3 mg kg-1, > muscles (1.9 ± 1.6 mg kg-1 and > spleen (1.0 ± 0.2 mg kg-1. As compared with heavy metal load observed in bear tissues between 1988 and 1990, the concentration of cadmium in the muscles and liver was significantly lower (p p p < 0.01. Lead and copper tissue concentrations did not change substantially.

  7. Salt ingestion caves.

    Directory of Open Access Journals (Sweden)

    Lundquist Charles A.

    2006-01-01

    Full Text Available Large vertebrate herbivores, when they find a salt-bearing layer of rock, say in a cliff face, can produce sizable voids where, overgenerations, they have removed and consumed salty rock. The cavities formed by this natural animal process constitute a uniqueclass of caves that can be called salt ingestion caves. Several examples of such caves are described in various publications. Anexample in Mississippi U.S.A., Rock House Cave, was visited by the authors in 2000. It seems to have been formed by deer orbison. Perhaps the most spectacular example is Kitum Cave in Kenya. This cave has been excavated to a length over 100 metersby elephants. An ancient example is La Cueva del Milodon in Chile, which is reported to have been excavated by the now extinctmilodon, a giant ground sloth. Still other possible examples can be cited. This class of caves deserves a careful definition. First, thecavity in rock should meet the size and other conventions of the locally accepted definition of a cave. Of course this requirement differsin detail from country to country, particularly in the matter of size. The intent is to respect the local conventions. The characteristicthat human entry is possible is judged to be a crucial property of any recognized cave definition. Second, the cavity should besignificantly the result of vertebrate animal consumption of salt-bearing rock. The defining process is that rock removed to form thecave is carried away in the digestive track of an animal. While sodium salts are expected to be the norm, other salts for which thereis animal hunger are acceptable. Also some other speleogenesis process, such as solution, should not be excluded as long as it issecondary in formation of a cave in question.

  8. Early cave art and ancient DNA record the origin of European bison

    DEFF Research Database (Denmark)

    Soubrier, Julien; Gower, Graham; Chen, Kefei

    2016-01-01

    The two living species of bison (European and American) are among the few terrestrial megafauna to have survived the late Pleistocene extinctions. Despite the extensive bovid fossil record in Eurasia, the evolutionary history of the European bison (or wisent, Bison bonasus) before the Holocene (<...

  9. The chronology of hand stencils in European Palaeolithic rock art: implications of new U-series results from El Castillo Cave (Cantabria, Spain).

    Science.gov (United States)

    García-Diez, Marcos; Garrido, Daniel; Hoffmann, Dirk; Pettitt, Paul; Pike, Alistair; Zilhão, Joao

    2015-07-20

    The hand stencils of European Paleolithic art tend to be considered of pre-Magdalenian age and scholars have generally assigned them to the Gravettian period. At El Castillo Cave, application of U-series dating to calcite accretions has established a minimum age of 37,290 years for underlying red hand stencils, implying execution in the earlier part of the Aurignacian if not beforehand. Together with the series of red disks, one of which has a minimum age of 40,800 years, these motifs lie at the base of the El Castillo parietal stratigraphy. The similarity in technique and colour support the notion that both kinds of artistic manifestations are synchronic and define an initial, non-figurative phase of European cave art. However, available data indicate that hand stencils continued to be painted subsequently. Currently, the youngest, reliably dated examples fall in the Late Gravettian, approximately 27,000 years ago.

  10. Small-scale modelling of cementation by descending silica-bearing fluids: Explanation of the origin of arenitic caves in South American tepuis

    Science.gov (United States)

    Aubrecht, R.; Lánczos, T.; Schlögl, J.; Audy, M.

    2017-12-01

    Geoscientific research was performed on South American table mountains (tepuis) and in their sandstone cave systems. To explain speleogenesis in these poorly soluble rocks, two theories were introduced: a) arenization theory implying selective weathering of quartz along grain boundaries and releasing of sand grains, b) selective lithification theory implying cementation by descending silica-bearing fluid flow. The latter theory presumes that the descending fluid flow becomes unstable on the interface between two layers with different porosity and splits to separate flow channels (so-called ;finger flow;). The arenites outside these channels remain uncemented. To verify the latter theory, small-scale modelling was performed, using layered sands and sodium-silicate solution. Fine to medium sand was used (0.08-0.5 mm), along with a coarse sand fraction (0.5-1.5 mm). The sands were layered and compacted in a transparent plastic boxes. Three liters of sodium-silicate solution (so-called water glass) were left to drip for several hours to the top of the sediment. The fine-grained layers were perfectly laterally impregnated, whereas the descending fluid flows split to ;fingers; in the coarse-grained layers due their higher hydraulic conductivity. This small-scale laboratory simulation mimics the real diagenesis by descending silica-bearing fluids and matches the real phenomena observed on the tepuis. The resulting cemented constructions closely mimic many geomorphological features observed on tepuis and inside their caves, e.g. ;finger-flow; pillars, overhangs, imperfectly formed (aborted) pillars in forms of hummocks hanging from ceilings, locally also thicker central pillars that originated by merging of smaller fluid-flow channels. The modelling showed that selective lithification theory can explain most of the geomorphological aspects related to the speleogenesis in tepuis.

  11. Steppe lion remains imported by Ice Age spotted hyenas into the Late Pleistocene Perick Caves hyena den in northern Germany

    Science.gov (United States)

    Diedrich, Cajus G.

    2009-05-01

    Upper Pleistocene remains of the Ice Age steppe lion Panthera leo spelaea (Goldfuss, 1810) have been found in the Perick Caves, Sauerland Karst, NW Germany. Bones from many hyenas and their imported prey dating from the Lower to Middle Weichselian have also been recovered from the Perick Cave hyena den. These are commonly cracked or exhibit deep chew marks. The absence of lion cub bones, in contrast to hyena and cave bear cub remains in the Perick Caves, and other caves of northern Germany, excludes the possibility that P. leo spelaea used the cave for raising cubs. Only in the Wilhelms Cave was a single skeleton of a cub found in a hyena den. Evidence of the chewing, nibbling and cracking of lion bones and crania must have resulted from the importation and destruction of lion carcasses (4% of the prey fauna). Similar evidence was preserved at other hyena den caves and open air sites in Germany. The bone material from the Perick and other Central European caves points to antagonistic hyena and lion conflicts, similar to clashes of their modern African relatives.

  12. Admixture and gene flow from Russia in the recovering Northern European brown bear (Ursus arctos).

    Science.gov (United States)

    Kopatz, Alexander; Eiken, Hans Geir; Aspi, Jouni; Kojola, Ilpo; Tobiassen, Camilla; Tirronen, Konstantin F; Danilov, Pjotr I; Hagen, Snorre B

    2014-01-01

    Large carnivores were persecuted to near extinction during the last centuries, but have now recovered in some countries. It has been proposed earlier that the recovery of the Northern European brown bear is supported by migration from Russia. We tested this hypothesis by obtaining for the first time continuous sampling of the whole Finnish bear population, which is located centrally between the Russian and Scandinavian bear populations. The Finnish population is assumed to experience high gene flow from Russian Karelia. If so, no or a low degree of genetic differentiation between Finnish and Russian bears could be expected. We have genotyped bears extensively from all over Finland using 12 validated microsatellite markers and compared their genetic composition to bears from Russian Karelia, Sweden, and Norway. Our fine masked investigation identified two overlapping genetic clusters structured by isolation-by-distance in Finland (pairwise FST = 0.025). One cluster included Russian bears, and migration analyses showed a high number of migrants from Russia into Finland, providing evidence of eastern gene flow as an important driver during recovery. In comparison, both clusters excluded bears from Sweden and Norway, and we found no migrants from Finland in either country, indicating that eastern gene flow was probably not important for the population recovery in Scandinavia. Our analyses on different spatial scales suggest a continuous bear population in Finland and Russian Karelia, separated from Scandinavia.

  13. The Jettencave, Southern Harz Mountains, Germany: Geophysical observations and a structural model of a shallow cave in gypsum/anhydrite-bearing rocks

    Science.gov (United States)

    Kaufmann, Georg; Romanov, Douchko

    2017-12-01

    Gypsum and anhydrite are soluble rocks, where fissures and bedding partings can be enlarged with time by the dissolution of the mineral species through water. The selective enlargement results in sub-surface voids acting as preferential flow path for the drainage of the rock. With time, larger cavities develop, and a network of cave passages can evolve. If the enlarged cave voids are not too deep under the surface, geophysical measurements can be used to detect, identify and trace these structures. We have used gravity measurements (GRAV), electrical resistivity imaging (ERI), self-potential measurements (SP), electrical conductivity measurements (EC), and ground-penetrating radar (GPR) above the cave Jettenhöhle, a cave located in the southern Harz Mountains in Germany. The Jettencave is developed in the Hauptanhydrit formation of the Permian Zechstein sequence, characterised by large breakdown rooms and an exposed water table. The overburden of the cave is only around 10-15 m, and dolomitic rocks are located in close vicinity. We present results from our geophysical surveys in vicinity of the cave. We are able to identify the cave geometry from GRAV, ERI, and GPR measurements, which distinguish the local lithology of the Permian Zechstein rocks in the area. From the ERI and EC measurements, we derive information on the void volume in the soluble rocks. We finally present a three-dimensional structural model of the Jettencave and its surroundings, based on our geophysical results and the hydrological interpretation.

  14. Hypogene caves of the central Appalachian Shenandoah Valley in Virginia

    Science.gov (United States)

    Doctor, Daniel H.; Orndorff, Wil

    2017-01-01

    Several caves in the Shenandoah Valley in Virginia show evidence for early hypogenic conduit development with later-enhanced solution under partly confined phreatic conditions guided by geologic structures. Many (but not all) of these caves have been subsequently invaded by surface waters as a result of erosion and exhumation. Those not so affected are relict phreatic caves, bearing no relation to modern drainage patterns. Field and petrographic evidence shows that carbonate rocks hosting certain relict phreatic caves were dolomitized and/or silicified by early hydrothermal fluid migration in zones that served to locally enhance rock porosity, thus providing preferential pathways for later solution by groundwater flow, and making the surrounding bedrock more resistant to surficial weathering to result in caves that reside within isolated hills on the land surface. Features suggesting that deep phreatic processes dominated the development of these relict caves include (1) cave passage morphologies indicative of ascending fluids, (2) cave plans of irregular pattern, reflecting early maze or anastomosing development, (3) a general lack of cave breakdown and cave streams or cave stream deposits, and (4) calcite wall and pool coatings within isolated caves intersecting the local water table, and within unroofed caves at topographic locations elevated well above the local base level. Episodes of deep karstification were likely separated by long periods of geologic time, encompassing multiple phases of sedimentary fill and excavation within caves, and reflect a complex history of deep fluid migration that set the stage for later shallow speleogenesis that continues today.

  15. Mitochondrial genomes reveal an explosive radiation of extinct and extant bears near the Miocene-Pliocene boundary.

    Science.gov (United States)

    Krause, Johannes; Unger, Tina; Noçon, Aline; Malaspinas, Anna-Sapfo; Kolokotronis, Sergios-Orestis; Stiller, Mathias; Soibelzon, Leopoldo; Spriggs, Helen; Dear, Paul H; Briggs, Adrian W; Bray, Sarah C E; O'Brien, Stephen J; Rabeder, Gernot; Matheus, Paul; Cooper, Alan; Slatkin, Montgomery; Pääbo, Svante; Hofreiter, Michael

    2008-07-28

    Despite being one of the most studied families within the Carnivora, the phylogenetic relationships among the members of the bear family (Ursidae) have long remained unclear. Widely divergent topologies have been suggested based on various data sets and methods. We present a fully resolved phylogeny for ursids based on ten complete mitochondrial genome sequences from all eight living and two recently extinct bear species, the European cave bear (Ursus spelaeus) and the American giant short-faced bear (Arctodus simus). The mitogenomic data yield a well-resolved topology for ursids, with the sloth bear at the basal position within the genus Ursus. The sun bear is the sister taxon to both the American and Asian black bears, and this clade is the sister clade of cave bear, brown bear and polar bear confirming a recent study on bear mitochondrial genomes. Sequences from extinct bears represent the third and fourth Pleistocene species for which complete mitochondrial genomes have been sequenced. Moreover, the cave bear specimen demonstrates that mitogenomic studies can be applied to Pleistocene fossils that have not been preserved in permafrost, and therefore have a broad application within ancient DNA research. Molecular dating of the mtDNA divergence times suggests a rapid radiation of bears in both the Old and New Worlds around 5 million years ago, at the Miocene-Pliocene boundary. This coincides with major global changes, such as the Messinian crisis and the first opening of the Bering Strait, and suggests a global influence of such events on species radiations.

  16. Mesolithic burial place in La Martina Cave (Dinant, Belgium)

    International Nuclear Information System (INIS)

    Dewez, M.; Gilot, E.; Groessens-Van-Dyck, M.C.; Cordy, J.M.

    1995-01-01

    The ''La Martina'' cave is located near Dinant (Belgium). Although the sediments had been shoveled out in the mid XIXth century, a calcic breccia has provided prehistoric bones. We can distinguish a Pleistocene fauna with cave bear, one Mesolithic burial place with two cromagnoid skeletons, from the 6th millennium BC, and some Holocene faunal remains. (authors). 7 refs

  17. Cave age determination

    International Nuclear Information System (INIS)

    Anon.

    1998-01-01

    To determine the age of a cave we have to determine the age of elements which were created at the same moment when the cave was. Usually a cave is dug out by infiltration of acid waters. During this alteration process rocks free some aluminium and potassium ions. In Carlsbad and Lechuguilla caves, scientists have found alunite, this aluminium and potassium sulfate can be dated by using the carbon method of age determination. (A.C.)

  18. Mitochondrial genomes reveal an explosive radiation of extinct and extant bears near the Miocene-Pliocene boundary

    Directory of Open Access Journals (Sweden)

    Rabeder Gernot

    2008-07-01

    Full Text Available Abstract Background Despite being one of the most studied families within the Carnivora, the phylogenetic relationships among the members of the bear family (Ursidae have long remained unclear. Widely divergent topologies have been suggested based on various data sets and methods. Results We present a fully resolved phylogeny for ursids based on ten complete mitochondrial genome sequences from all eight living and two recently extinct bear species, the European cave bear (Ursus spelaeus and the American giant short-faced bear (Arctodus simus. The mitogenomic data yield a well-resolved topology for ursids, with the sloth bear at the basal position within the genus Ursus. The sun bear is the sister taxon to both the American and Asian black bears, and this clade is the sister clade of cave bear, brown bear and polar bear confirming a recent study on bear mitochondrial genomes. Conclusion Sequences from extinct bears represent the third and fourth Pleistocene species for which complete mitochondrial genomes have been sequenced. Moreover, the cave bear specimen demonstrates that mitogenomic studies can be applied to Pleistocene fossils that have not been preserved in permafrost, and therefore have a broad application within ancient DNA research. Molecular dating of the mtDNA divergence times suggests a rapid radiation of bears in both the Old and New Worlds around 5 million years ago, at the Miocene-Pliocene boundary. This coincides with major global changes, such as the Messinian crisis and the first opening of the Bering Strait, and suggests a global influence of such events on species radiations.

  19. Spinal spondylosis and acute intervertebral disc prolapse in a European brown bear (Ursus arctos arctos : clinical communication

    Directory of Open Access Journals (Sweden)

    W.M. Wagner

    2005-06-01

    Full Text Available A 22-year-old male European brown bear (Ursus arctos arctos was presented to the Onderstepoort Veterinary Academic Hospital after an acute onset of hind limb paralysis 4 days earlier. Previous radiographs revealed marked degenerative joint disease of the stifles, tarsi and digits. The clinical findings were consistent with acute disc prolapse. Lateral radiographs of the entire vertebral column were made as well as ventrodorsal pelvic radiographs. The latter were within normal limits. The vertebral column revealed multiple lesions consistent with chronic and acute disc herniations. Lateral compression of the caudal lumbar nerve roots could not be ruled out. Owing to multiple significant findings of the vertebral column and the poor prognosis for full recovery after surgery, the bear was euthanased. The diagnosis of an acute disc prolapse and multiple chronic disc herniations was confirmed on necropsy.

  20. Uranium-series dating of fossil bones from alpine caves

    International Nuclear Information System (INIS)

    Leitner-Wild, E.; Steffan, I.

    1993-01-01

    During the course of an investigation of fossil cave bear populations the uranium-series method for absolute age determination has been applied to bone material. The applicability of the method to bone samples from alpine caves is demonstrated by the concordance of U/Th and U/Pa ages and cross-checks with the radiocarbon method. Stratigraphic agreement between bone ages and carbonate speleothem ages also indicates the potential of the uranium-series method as a suitable tool for the age determination of fossil bones from alpine cave environments. (Author)

  1. Clastic cave deposits in Botovskaya cave (Eastern Siberia, Russian Federation)

    Czech Academy of Sciences Publication Activity Database

    Kadlec, Jaroslav; Chadima, Martin; Lisá, Lenka; Hercman, H.; Osintsev, A.; Oberhänsli, H.

    2008-01-01

    Roč. 70, č. 3 (2008), s. 142-155 ISSN 1090-6924 Institutional research plan: CEZ:AV0Z30130516 Keywords : cave sediments * mineral magnetism * Botovskaya Cave Subject RIV: DE - Earth Magnetism, Geodesy, Geography Impact factor: 0.532, year: 2008 http://www.caves.org/pub/journal/Journal_of_Cave_and_Karst_Studies_volume_70.htm

  2. Speleothem (Cave Deposit) Data

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Records of past temperature, precipitation, and other aspects of climate derived from mineral deposits found in caves. Parameter keywords describe what was measured...

  3. Environmental record in detrital cave sediments in the Botovskaya and Dolganskaya Jama caves (Russian Federation)

    Czech Academy of Sciences Publication Activity Database

    Lisá, Lenka; Kadlec, Jaroslav; Chadima, Martin; Hercman, H.; Oberhansli, H.; Osincev, A.

    2006-01-01

    Roč. 8, - (2006), A10273-A10273 ISSN 1029-7006. [European Geosciences Union General Assembly. 02.04.2006-07.04.2006, Vienna] Institutional research plan: CEZ:AV0Z30130516 Keywords : cave * sediments * micromorphology * magnetic properties * provenance Subject RIV: DB - Geology ; Mineralogy http://www.cosis.net/abstracts/EGU06/10273/EGU06-J-10273-2.pdf

  4. Energy expenditure in caving.

    Directory of Open Access Journals (Sweden)

    Giorgia Antoni

    Full Text Available The aim of this study was to determine the energy expenditure of a group of cavers of both genders and different ages and experience during a 10 hour subterranean exploration, using portable metabolimeters. The impact of caving activity on body composition and hydration were also assessed through bioelectrical impedance, and nutritional habits of cavers surveyed. During cave activity, measured total energy expenditure (TEE was in the range 225-287 kcal/h for women-men (MET = 4.1, respectively; subjects had an energy intake from food in the range 1000-1200 kcal, thus inadequate to restore lost calories. Bayesian statistical analysis estimated the effect of predictive variables on TEE, revealing that experienced subjects had a 5% lower TEE than the less skilled ones and that women required a comparatively larger energy expenditure than men to perform the same task. BIVA (bioelectrical impedance vector analysis showed that subjects were within the range of normal hydration before and after cave activity, but bioelectrical changes indicated a reduction of extracellular water in men, which might result in hypo-osmolal dehydration in the case of prolonged underground exercise. All these facts should be considered when planning cave explorations, preparing training programs for subjects practising caving, and optimizing a diet for cavers. Further, information gathered through this study could be of value to reduce accidents in caves related to increase in fatigue.

  5. Cryogenic Cave Pearls In the Periglacial Zones of Ice Caves

    Czech Academy of Sciences Publication Activity Database

    Žák, Karel; Orvošová, M.; Filippi, Michal; Vlček, M.; Onac, B. P.; Persoiu, A.; Rohovec, Jan; Světlík, Ivo

    2013-01-01

    Roč. 83, č. 2 (2013), s. 207-220 ISSN 1527-1404 R&D Projects: GA ČR GAP210/10/1760 Institutional research plan: CEZ:AV0Z30130516 Institutional support: RVO:67985831 ; RVO:61389005 Keywords : caves * cryogenic caves * ice caves * periglacial zones Subject RIV: DB - Geology ; Mineralogy Impact factor: 1.943, year: 2013

  6. The fungal colonisation of rock-art caves: experimental evidence.

    Science.gov (United States)

    Jurado, Valme; Fernandez-Cortes, Angel; Cuezva, Soledad; Laiz, Leonila; Cañaveras, Juan Carlos; Sanchez-Moral, Sergio; Saiz-Jimenez, Cesareo

    2009-09-01

    The conservation of rock-art paintings in European caves is a matter of increasing interest. This derives from the bacterial colonisation of Altamira Cave, Spain and the recent fungal outbreak of Lascaux Cave, France-both included in the UNESCO World Heritage List. Here, we show direct evidence of a fungal colonisation of rock tablets in a testing system exposed in Altamira Cave. After 2 months, the tablets, previously sterilised, were heavily colonised by fungi and bacteria. Most fungi isolated were labelled as entomopathogens, while the bacteria were those regularly identified in the cave. Rock colonisation was probably promoted by the dissolved organic carbon supplied with the dripping and condensation waters and favoured by the displacement of aerosols towards the interior of the cave, which contributed to the dissemination of microorganisms. The role of arthropods in the dispersal of spores may also help in understanding fungal colonisation. This study evidences the fragility of rock-art caves and demonstrates that microorganisms can easily colonise bare rocks and materials introduced into the cavity.

  7. Magnetic Susceptibility and Heavy Metals in Guano from South Sulawesi Caves

    Science.gov (United States)

    Rifai, H.; Putra, R.; Fadila, M. R.; Erni, E.; Wurster, C. M.

    2018-04-01

    Measurement of some magnetic properties have been performed on vertical profile from South Sulawesi caves (Mampu and Bubau) by using low cost, rapid, sensitive and non destructive magnetic method. The aim is to attempt to use magnetic characters as a fingerprint for anthropogenic pollution in the caves. Guano samples were collected every 5 cm at a certain section of Mampu and Bubau cave, South Sulawesi, starting from surface through 300 cm in depth of mampu Cave and 30 cm of Bubau Cave. The magnetic parameters such as magnetic susceptibility and percentage frequency dependence susceptibility were measured using the Bartington MS2-MS2B instruments and supported by X-Ray Fluoroscence (XRF) to know their element composition. The results show that the samples had variations in magnetic susceptibility from 3.5 to 242.6 x 10‑8 m3/kg for Mampu Cave and from 8.6 to 106.5 x 10‑8 m3/kg for Bubau Cave and also magnetic domain. Then, the XRF results show that the caves contain several heavy metals. Magnetic and heavy metal analyses showing that the magnetic minerals in caves are lithogenic (Fe-bearing minerals) in origin and anthropogenic (Zn content) in the caves.

  8. Differential preservation of vertebrates in Southeast Asian caves

    Directory of Open Access Journals (Sweden)

    Julien Louys

    2017-09-01

    Full Text Available Caves have been an important source of vertebrate fossils for much of Southeast Asia, particularly for the Quaternary. Despite this importance, the mechanisms by which vertebrate remains accumulate and preserve in Southeast Asian caves has never been systematically reviewed or examined. Here, we present the results of three years of cave surveys in Indonesia and Timor-Leste, describing cave systems and their attendant vertebrate accumulations in diverse geological, biogeographical, and environmental settings. While each cave system is unique, we find that the accumulation and preservation of vertebrate remains are highly dependent on local geology and environment. These factors notwithstanding, we find the dominant factor responsible for faunal deposition is the presence or absence of biological accumulating agents, a factor directly dictated by biogeographical history. In small, isolated, volcanic islands, the only significant accumulation occurs in archaeological settings, thereby limiting our understanding of the palaeontology of those islands prior to human arrival. In karstic landscapes on both oceanic and continental islands, our understanding of the long-term preservation of vertebrates is still in its infancy. The formation processes of vertebrate-bearing breccias, their taphonomic histories, and the criteria used to determine whether these represent syngenetic or multiple deposits remain critically understudied. The latter in particular has important implications for arguments on how breccia deposits from the region should be analysed and interpreted when reconstructing palaeoenvironments.

  9. Diet and morphology of extant and recently extinct northern bears

    Science.gov (United States)

    Mattson, David J.

    1998-01-01

    I examined the relationship of diets to skull morphology of extant northern bears and used this information to speculate on diets of the recently extinct cave (Ursus spelaeus) and short-faced (Arctodus simus) bears. Analyses relied upon published skull measurements and food habits of Asiatic (U. thibetanus) and American (U. americanus) black bears, polar bears (U. maritimus), various subspecies of brown bears (U. arctos), and the giant panda (Ailuropoda melanoleuca). Principal components analysis showed major trends in skull morphology related to size, crushing force, and snout shape. Giant pandas, short-faced bears, cave bears, and polar bears exhibited extreme features along these gradients. Diets of brown bears in colder, often non-forested environments were distinguished by large volumes of roots, foliage, and vertebrates, while diets of the 2 black bear species and brown bears occupying broadleaf forests contained greater volumes of mast and invertebrates and overlapped considerably. Fractions of fibrous foods in feces (foliage and roots) were strongly related to skull morphology (R2=0.97)">(R2=0.97). Based on this relationship, feces of cave and short-faced bears were predicted to consist almost wholly of foliage, roots, or both. I hypothesized that cave bears specialized in root grubbing. In contrast, based upon body proportions and features of the ursid digestive tract, I hypothesized that skull features associated with crushing force facilitated a carnivorous rather than herbivorous diet for short-faced bears.

  10. Survey and hydrogeology of Carroll Cave

    Science.gov (United States)

    Carroll Cave, located in Camden County, Missouri, is the largest known cave formed in the Gasconade Dolomite of the Salem Plateau. Despite extensive visitation over the last 50 years and multiple survey efforts, a comprehensive map of the cave has never been produced. In 2002, the Carroll Cave Conse...

  11. Census of biodiversity in marine caves of the eastern Mediterranean Sea

    Directory of Open Access Journals (Sweden)

    V. GEROVASILEIOU

    2015-03-01

    Full Text Available Scientific information on the biodiversity of marine caves in the eastern Mediterranean is limited, especially when considering the extensively studied caves of the north-western and central Mediterranean. Aiming to enhance current knowledge regarding cave communities, this study represents a first assessment of the marine cave biota of the eastern Mediterranean, as this has been defined by the European Union’s Marine Strategy Framework Directive (MSFD. Information retrieved from an extensive overview of relevant scientific documents was combined with original data recorded from 23 marine caves of the north-eastern Mediterranean. Our results report a total of 520 taxa recorded in eastern Mediterranean marine caves to date, the majority of which are sponges, polychaetes, rhodophytes, bivalves, fishes, and gastropods. These include several protected, endemic, and alien species. However, not all taxonomic groups have been equally studied among different areas and future studies are expected to raise the number of endemic and alien species. The overall observed trend is that the reported species number is generally related to sampling effort and scientific expertise. The most well-studied marine cave communities of the eastern Mediterranean are those of the Aegean Sea (especially its northern sector, which presented the highest number of species, followed by those of the Levantine. Furthermore, our research in Aegean caves revealed numerous new records for the marine cave fauna of the eastern basin, while several species are reported for the first time in the marine cave habitat. The critical need for further scientific research, monitoring, and conservation of this unique ecosystem was highlighted by (i the presence of certain species endemic to the eastern Mediterranean coupled with a high proportion of alien species, especially in the Levantine, and (ii the marine cave habitat availability in isolated insular areas of the eastern Mediterranean.

  12. Spiders in caves.

    Science.gov (United States)

    Mammola, Stefano; Isaia, Marco

    2017-04-26

    World experts of different disciplines, from molecular biology to macro-ecology, recognize the value of cave ecosystems as ideal ecological and evolutionary laboratories. Among other subterranean taxa, spiders stand out as intriguing model organisms for their ecological role of top predators, their unique adaptations to the hypogean medium and their sensitivity to anthropogenic disturbance. As the description of the first eyeless spider ( Stalita taenaria ), an array of papers on subterranean spider biology, ecology and evolution has been published, but a comprehensive review on these topics is still lacking. We provide a general overview of the spider families recorded in hypogean habitats worldwide, we review the different adaptations of hypogean spiders to subterranean life, and we summarize the information gathered so far about their origin, population structure, ecology and conservation status. Finally, we point out the limits of the knowledge we currently have regarding hypogean spiders, aiming to stimulate future research. © 2017 The Author(s).

  13. Cave breakdown by vadose weathering.

    Directory of Open Access Journals (Sweden)

    Osborne R. Armstrong L.

    2002-01-01

    Full Text Available Vadose weathering is a significant mechanism for initiating breakdown in caves. Vadose weathering of ore bodies, mineral veins, palaeokarst deposits, non-carbonate keystones and impure, altered or fractured bedrock, which is intersected by caves, will frequently result in breakdown. Breakdown is an active, ongoing process. Breakdown occurs throughout the vadose zone, and is not restricted to large diameter passages, or to cave ceilings. The surfaces of disarticulated blocks are commonly coated, rather than having fresh broken faces, and blocks continue to disintegrate after separating from the bedrock. Not only gypsum, but also hydromagnesite and aragonite are responsible for crystal wedging. It is impossible to study or identify potential breakdown foci by surface surveys alone, in-cave observation and mapping are essential.

  14. Exposure to radon in Cuban tourist caves

    International Nuclear Information System (INIS)

    Carrazana Gonzalez, Jorge; Dominguez Ley, Orlando; Gil Castillo, Reinaldo; Molerio Leon, Leslie

    2008-01-01

    With the objective of estimating the dose, due to Radon-222, received by tour guides and other people who work inside some of the most important tourist caves in the Republic of Cuba, measurements of radon concentrations were carried out in four of these caves: Santo Tomas Cave, Tapiada Cave, Del Indio Cave and Jose Miguel Cave. All these caves are located in the Vinales Valley (Pinar del Rio City), a very important tourist area in the country. The relationship among radon concentration, the concentration of natural radionuclides inside the caves and the geologic characteristics of the specific locations was analyzed. In order to select the most appropriates measurement places, different criteria were taken into account: representatives points of the geology of the caves, level of gamma radiation, exchange of air, places of work inside the caves (cafeterias, restaurants and shops) and places more frequently visited by tour guides. The maximum radon concentration was found in Jose Miguel Cave with a value of 220 Bq/m 3 . The measurement of gamma dose rate inside the caves was carried out with a scintillation detector type Scintrex BGS-3 previously calibrated at SSI, Sweden. The radon concentrations were measured with the equipment Alpha Guard PQ2000/MC50 and SARAD RM2000, both also calibrated at SSI, Sweden. The obtained results indicated that, in the studied caves, the annual dose is not greater than 1 mSv considering a work year of 2000 hours. (author)

  15. GEOMORPHIC ANALYSIS OF MAWSMAI CAVE, MEGHALAYA, INDIA

    Directory of Open Access Journals (Sweden)

    Vibhash Chandra Jha

    2011-12-01

    Full Text Available ABSTRACT Caving is an art which can be best experienced in the mystic Mawsmai Cave of Meghalaya. This Cave is fast becoming a hot tourist’s destination offering great adventurous opportunity to the tourists. The cave is located in the East Khasi Hill region near Cherrapunjee and is made of limestone. The emotion of thrill heightens after entering the cave. The entrance has a narrow vertical opening and is well lit. Due to its location in the world’s largest rainfall region, dripping of water from the cave roofs occurs almost throughout the year. The formation of stalactites and stalagmites create wonderful phenomena specially found in this caves. The conspicuous pillars formed due to the joining of the roof and the floors are an awe-inspiring creativity of the creator of this world. Keywords: Cave, Limestone, Stalactite, Stalagmite, Pillar, Solution.

  16. The future of the CAVE

    KAUST Repository

    DeFanti, Thomas; Acevedo-Feliz, Daniel; Ainsworth, Richard; Brown, Maxine; Cutchin, Steven; Dawe, Gregory; Doerr, Kai-Uwe; Johnson, Andrew; Knox, Christopher; Kooima, Robert; Kuester, Falko; Leigh, Jason; Long, Lance; Otto, Peter; Petrovic, Vid; Ponto, Kevin; Prudhomme, Andrew; Rao, Ramesh; Renambot, Luc; Sandin, Daniel; Schulze, Jurgen; Smarr, Larry; Srinivasan, Madhusudhanan; Weber, Philip; Wickham, Gregory

    2011-01-01

    The CAVE, a walk-in virtual reality environment typically consisting of 4–6 3 m-by-3 m sides of a room made of rear-projected screens, was first conceived and built in 1991. In the nearly two decades since its conception, the supporting technology has improved so that current CAVEs are much brighter, at much higher resolution, and have dramatically improved graphics performance. However, rear-projection-based CAVEs typically must be housed in a 10 m-by-10 m-by-10 m room (allowing space behind the screen walls for the projectors), which limits their deployment to large spaces. The CAVE of the future will be made of tessellated panel displays, eliminating the projection distance, but the implementation of such displays is challenging. Early multi-tile, panel-based, virtual-reality displays have been designed, prototyped, and built for the King Abdullah University of Science and Technology (KAUST) in Saudi Arabia by researchers at the University of California, San Diego, and the University of Illinois at Chicago. New means of image generation and control are considered key contributions to the future viability of the CAVE as a virtual-reality device.

  17. Chronology of guitarrero cave, peru.

    Science.gov (United States)

    Lynch, T F; Gillespie, R; Gowlett, J A; Hedges, R E

    1985-08-30

    Dating by accelerator mass spectrometry of wooden artifacts, cord, and charcoal samples from Guitarrero Cave, Peru, supports the antiquity of South America's earliest textiles and other perishable remains. The new dates are consistent with those obtained from disintegration counters and leave little doubt about the integrity of the lower Preceramic layers and their early cultivars. Re-evaluation of the mode of deposition suggests that most of the remains resulted from short-term use of the cave in the eighth millennium B.C., with a possible brief human visit as early as 12,560 years ago.

  18. 3N Cave: Longest salt cave in the world

    Czech Academy of Sciences Publication Activity Database

    Bruthans, J.; Filippi, Michal; Zare, M.; Asadi, N.; Vilhelm, Z.

    2006-01-01

    Roč. 64, č. 9 (2006), s. 10-18 ISSN 0027-7010 R&D Projects: GA AV ČR(CZ) KJB301110501 Institutional research plan: CEZ:AV0Z30130516 Keywords : salt cave * salt karst * Iran * expedition Namak Subject RIV: DB - Geology ; Mineralogy

  19. Comparing flow-through and static ice cave models for Shoshone Ice Cave

    Directory of Open Access Journals (Sweden)

    Kaj E. Williams

    2015-05-01

    Full Text Available In this paper we suggest a new ice cave type: the “flow-through” ice cave. In a flow-through ice cave external winds blow into the cave and wet cave walls chill the incoming air to the wet-bulb temperature, thereby achieving extra cooling of the cave air. We have investigated an ice cave in Idaho, located in a lava tube that is reported to have airflow through porous wet end-walls and could therefore be a flow-through cave. We have instrumented the site and collected data for one year. In order to determine the actual ice cave type present at Shoshone, we have constructed numerical models for static and flow-through caves (dynamic is not relevant here. The models are driven with exterior measurements of air temperature, relative humidity and wind speed. The model output is interior air temperature and relative humidity. We then compare the output of both models to the measured interior air temperatures and relative humidity. While both the flow-through and static cave models are capable of preserving ice year-round (a net zero or positive ice mass balance, both models show very different cave air temperature and relative humidity output. We find the empirical data support a hybrid model of the static and flow-through models: permitting a static ice cave to have incoming air chilled to the wet-bulb temperature fits the data best for the Shoshone Ice Cave.

  20. The microbiology of Lascaux Cave

    Czech Academy of Sciences Publication Activity Database

    Bastian, F.; Jurado, V.; Nováková, Alena; Alabouvette, C.; Saiz-Jimenez, C.

    2010-01-01

    Roč. 156, č. 3 (2010), s. 644-652 ISSN 1350-0872 Institutional research plan: CEZ:AV0Z60660521 Keywords : Lascaux Cave * microbiology * Paleolithic paintings Subject RIV: EH - Ecology, Behaviour Impact factor: 2.957, year: 2010

  1. Bioaccumulation of eight heavy metals in cave animals from Dashui ...

    African Journals Online (AJOL)

    ajl2

    karst caves and water systems in the caves are well developed. So, heavy metals can contaminate cave envi- ronment and affect cave animals. Karst topography is widely distributed in Guizhou province, China, accounting for 73.8% of the total land area. So, the examination of heavy metal pollution in cave soil and water ...

  2. Environmental conditions of Borra Cave, Visakhapattanam, India

    Directory of Open Access Journals (Sweden)

    Haraprasad Bairagya

    2014-05-01

    Full Text Available Caving is an art which can be best experienced in the mystic Borra of Eastern Ghats and ranked as the second largest cave of India just after Belum Caves situated in the same state Andhrapradesh, India. This Cave is fast becoming a hot tourist?s destination offering great adventurous opportunity to the tourists in the Eastern Ghats. The cave is located in the Ananthagiri hills of the Eastern Ghats region near Visakhapattanam and is made of limestone. The emotion of thrill heightens after entering the cave. The entrance has a narrow vertical opening and is well lit. Due to its location in the sub-equatorial region, dripping of water from the cave roofs occurs almost throughout the year. The formation of stalactites and stalagmites create wonderful phenomena specially found in this cave. The conspicuous pillars formed due to the joining of the roof and the floors are an awe-inspiring creativity of the creator of this world. Various viruses and bacteria are in the cave interior along with different other creatures. The Borra cave helps the Govt. of Andhra Pradesh, India, to earn huge economic benefits for the sake of tourism industry. DOI: http://dx.doi.org/10.3126/ije.v3i2.10526 International Journal of the Environment Vol.3(2 2014: 150-166

  3. Pathogenic and opportunistic microorganisms in caves

    Directory of Open Access Journals (Sweden)

    Sanchez-Moral Sergio

    2010-01-01

    Full Text Available With today’s leisure tourism, the frequency of visits to many caves makes it necessary to know about possible potentially pathogenic microorganisms in caves, determine their reservoirs, and inform the public about the consequences of such visits. Our data reveal that caves could be a potential danger to visitors because of the presence of opportunistic microorganisms, whose existence and possible development in humans is currently unknown.

  4. Candidate cave entrances on Mars

    Science.gov (United States)

    Cushing, Glen E.

    2012-01-01

    This paper presents newly discovered candidate cave entrances into Martian near-surface lava tubes, volcano-tectonic fracture systems, and pit craters and describes their characteristics and exploration possibilities. These candidates are all collapse features that occur either intermittently along laterally continuous trench-like depressions or in the floors of sheer-walled atypical pit craters. As viewed from orbit, locations of most candidates are visibly consistent with known terrestrial features such as tube-fed lava flows, volcano-tectonic fractures, and pit craters, each of which forms by mechanisms that can produce caves. Although we cannot determine subsurface extents of the Martian features discussed here, some may continue unimpeded for many kilometers if terrestrial examples are indeed analogous. The features presented here were identified in images acquired by the Mars Odyssey's Thermal Emission Imaging System visible-wavelength camera, and by the Mars Reconnaissance Orbiter's Context Camera. Select candidates have since been targeted by the High-Resolution Imaging Science Experiment. Martian caves are promising potential sites for future human habitation and astrobiology investigations; understanding their characteristics is critical for long-term mission planning and for developing the necessary exploration technologies.

  5. Measurements of radon levels inside Mexican caves

    International Nuclear Information System (INIS)

    Borau, J.; Gonzalez, A.; Espinosa, G.; Golzarri, J.I.

    1993-01-01

    Living animal species on earth have been exposed to environmental radon from the very beginning of time. The effects of radiation, combined with other natural parameters such as temperature, humidity, salt contents, etc., have most likely influenced the evaluation of different species. Thus, it is important to know and to evaluate the radon levels, among other radioactive elements present in enclosed environments such as caves, especially since those caves were also the dwellings and refuge of the predecessor of man. In this work we present radon level measurements inside some caves with vestiges of ancient inhabitats and some recently discovered natural caves, using Nuclear Track Detectors. (author)

  6. Bearing system

    Science.gov (United States)

    Kapich, Davorin D.

    1987-01-01

    A bearing system includes backup bearings for supporting a rotating shaft upon failure of primary bearings. In the preferred embodiment, the backup bearings are rolling element bearings having their rolling elements disposed out of contact with their associated respective inner races during normal functioning of the primary bearings. Displacement detection sensors are provided for detecting displacement of the shaft upon failure of the primary bearings. Upon detection of the failure of the primary bearings, the rolling elements and inner races of the backup bearings are brought into mutual contact by axial displacement of the shaft.

  7. Millipedes (Diplopoda) from caves of Portugal

    DEFF Research Database (Denmark)

    P. S. Reboleira, Ana Sofia; Enghoff, Henrik

    2014-01-01

    in caves of the mainland and the island of Madeira has provided new data about the distribution and diversity of millipedes. A review of millipedes from caves of Portugal is presented, listing fourteen species belonging to eight families, among which six species are considered troglobionts...

  8. Microbiological and environmental issues in show caves.

    Science.gov (United States)

    Saiz-Jimenez, Cesareo

    2012-07-01

    Cultural tourism expanded in the last half of the twentieth century, and the interest of visitors has come to include caves containing archaeological remains. Some show caves attracted mass tourism, and economical interests prevailed over conservation, which led to a deterioration of the subterranean environment and the rock art. The presence and the role of microorganisms in caves is a topic that is often ignored in cave management. Knowledge of the colonisation patterns, the dispersion mechanisms, and the effect on human health and, when present, over rock art paintings of these microorganisms is of the utmost importance. In this review the most recent advances in the study of microorganisms in caves are presented, together with the environmental implications of the findings.

  9. The Mammoth Cave system, Kentucky, USA

    International Nuclear Information System (INIS)

    Palmer, A. N.

    2016-01-01

    Mammoth Cave is the main attraction of Mammoth Cave National Park. For several decades it has been the longest known cave in the world and currently contains 652 km in 2016 of surveyed passages. It is located in the heart of an extensive karst plateau, in which the stratal dip averages only one degree. The cave is part of a drainage basin of more than 200 km 2 . The cave has been known to local inhabitants for several millennia and contains a rich trove of archaeological and historical artifacts. It contains many speleo biota including several rare and endangered species and has been designated a World Heritage Site and an International Biosphere Reserve (UNESCO). Its many passage levels and sediments contain a record of the fluvial history of most of south-eastern North America. (Author)

  10. Pleistocene cave art from Sulawesi, Indonesia.

    Science.gov (United States)

    Aubert, M; Brumm, A; Ramli, M; Sutikna, T; Saptomo, E W; Hakim, B; Morwood, M J; van den Bergh, G D; Kinsley, L; Dosseto, A

    2014-10-09

    Archaeologists have long been puzzled by the appearance in Europe ∼40-35 thousand years (kyr) ago of a rich corpus of sophisticated artworks, including parietal art (that is, paintings, drawings and engravings on immobile rock surfaces) and portable art (for example, carved figurines), and the absence or scarcity of equivalent, well-dated evidence elsewhere, especially along early human migration routes in South Asia and the Far East, including Wallacea and Australia, where modern humans (Homo sapiens) were established by 50 kyr ago. Here, using uranium-series dating of coralloid speleothems directly associated with 12 human hand stencils and two figurative animal depictions from seven cave sites in the Maros karsts of Sulawesi, we show that rock art traditions on this Indonesian island are at least compatible in age with the oldest European art. The earliest dated image from Maros, with a minimum age of 39.9 kyr, is now the oldest known hand stencil in the world. In addition, a painting of a babirusa ('pig-deer') made at least 35.4 kyr ago is among the earliest dated figurative depictions worldwide, if not the earliest one. Among the implications, it can now be demonstrated that humans were producing rock art by ∼40 kyr ago at opposite ends of the Pleistocene Eurasian world.

  11. PIXE analysis of cave sediments, prehispanic paintings and obsidian cutting tools from Baja California Sur caves

    International Nuclear Information System (INIS)

    Miranda, J.; Oliver, A.; Dacal, A.; Ruvalcaba, J.L.; Cruz, F.; Ortiz, M.E.; Vinas, R.

    1993-01-01

    Elemental PIXE analysis of cave sediments, minerals, pigments of the prehispanic paintings and obsidian cutting tools from caves in Baja California Sur has been carried out with a 0.7 MeV proton beam. The elements analysed in this sample set (Al to Co) provide an idea of the environment of the caves. The obsidian data analysis suggests that the human communities who made these painting used more than one obsidian source to manufacture cutting tools. (orig.)

  12. Bacterial community survey of sediments at Naracoorte Caves, Australia

    Directory of Open Access Journals (Sweden)

    Ball Andrew S.

    2012-07-01

    Full Text Available Bacterial diversity in sediments at UNESCO World Heritage listed Naracoorte Caves was surveyed as part of an investigation carried out in a larger study on assessing microbial communities in caves. Cave selection was based on tourist accessibility; Stick Tomato and Alexandra Cave (> 15000 annual visits and Strawhaven Cave was used as control (no tourist access. Microbial analysis showed that Bacillus was the most commonly detected microbial genus by culture dependent and independent survey of tourist accessible and inaccessible areas of show (tourist accessible and control caves. Other detected sediment bacterial groups were assigned to the Firmicutes, Actinobacteria and Proteobacteria. The survey also showed differences in bacterial diversity in caves with human access compared to the control cave with the control cave having unique microbial sequences (Acinetobacter, Agromyces, Micrococcus and Streptomyces. The show caves had higher bacterial counts, different 16S rDNA based DGGE cluster patterns and principal component groupings compared to Strawhaven. Different factors such as human access, cave use and configurations could have been responsible for the differences observed in the bacterial community cluster patterns (tourist accessible and inaccessible areas of these caves. Cave sediments can therefore act as reservoirs of microorganisms. This might have some implications on cave conservation activities especially if these sediments harbor rock art degrading microorganisms in caves with rock art.

  13. NAK WP-Cave project

    International Nuclear Information System (INIS)

    Svemar, C.

    1985-11-01

    WP-Cave is designed as an egg-shaped underground structure for intermediate storing and final disposal of high-level nuclear waste. Its height, when storing 1600 tonnes of spent fuel, is about 250 m and its diameter 110 m at mid-height. The waste storage has a compact layout and is surrounded by two engineered barriers. The innermost one is a 5 m-wide shield consisting of a mixture of bentonite clay and same which has a low hydraulic conductivity. This shield is surrounded by a so-called hydraulic cage, which initially drains the storage rock mass and, in the long-term diverts, the ground water flow past the storage. In this way an initial dry supervision period can be maintained. After sealing-off the storage and after water-filling, a stagnant chemical environment is established inside the bentonite-sand barrier preventing the disposed waste from being dissolved and from migrating to the geosphere. The programme, as outlined by the Project Board, has considered R and D questions with specific relation to the WP-Cave such as: properties of low-graded bentonite mixtures, function of the hydraulic cage, full-face boring of the storage, geomechanics of the storage and the bentonite-sand barrier, dry ventilation of the storage, temperature distributions and thermal stresses. An initial safety analysis has also been conducted. The hydraulic conductivity of low-grade bentonite mixtures has been measured in laboratory tests and found to be higher than expected. Tests of gas conductivity, for instance, confirm that only low gas pressures would build up inside the bentonite-sand barrier. The initial safety analysis indicates that a compact storage, such as that presented, would allow for the safe isolation of the spent nuclear fuel and would fulfull the radiation protection criterion of 0.1 mSv/year. With 27 refs. (Author)

  14. Visualization framework for CAVE virtual reality systems

    OpenAIRE

    Kageyama, Akira; Tomiyama, Asako

    2016-01-01

    We have developed a software framework for scientific visualization in immersive-type, room-sized virtual reality (VR) systems, or Cave automatic virtual environment (CAVEs). This program, called Multiverse, allows users to select and invoke visualization programs without leaving CAVE’s VR space. Multiverse is a kind of immersive “desktop environment” for users, with a three-dimensional graphical user interface. For application developers, Multiverse is a software framework with useful class ...

  15. Stress analysis of longwall top coal caving

    Energy Technology Data Exchange (ETDEWEB)

    Alehossein, H.; Poulsen, B.A. [CSIRO Exploration & Mining, Brisbane, Qld. (Australia)

    2010-01-15

    Longwall top coal caving (LTCC) is a relatively new method of mining thick coal seams that is currently achieving high productivity and efficiency. The technique is similar to traditional longwall mining in that a cutting head slices coal from the lower section of the coal seam onto a conveyor belt installed in front of the hydraulic support near the cutting face. In modern LTCC an additional rear conveyor belt is located behind the support, to which the flow of the caved coal from the upper part of the seam can be controlled by a moveable flipper attached to the canopy of the support. The mining method relies on the fracturing of the top coal by the front abutment pressure to achieve satisfactory caving into the rear conveyor. This paper develops a yield and caveability criterion based on in situ conditions in the top coal in advance of the mining face (yield) and behind the supports (caveability). Yielding and caving effects are combined into one single number called caving number (CN), which is the multiplication result of caving factor (CF) and yield factor (YF). Analytical derivations are based on in situ stress conditions, Mohr-Coulomb and/or Hoek-Brown rock failure criteria and an on-associated elastoplastic strain softening material behaviour. The yield and caveability criteria are in agreement with results from both numerical studies and mine data. The caving number is normalised to mining conditions of a reference Chinese mine (LMX mine) and is used to assess LTCC performance at fourteen other Chinese working longwalls that have had varying success with the LTCC technology. As a predictive model, results of this analytical/numerical study are useful to assess the potential success of caving in new LTCC operations and in different mining conditions.

  16. Distinction between epigenic and hypogenic maze caves

    Science.gov (United States)

    Palmer, Arthur N.

    2011-11-01

    Certain caves formed by dissolution of bedrock have maze patterns composed of closed loops in which many intersecting fractures or pores have enlarged simultaneously. Their origin can be epigenic (by shallow circulation of meteoric groundwater) or hypogenic (by rising groundwater or production of deep-seated solutional aggressiveness). Epigenic mazes form by diffuse infiltration through a permeable insoluble caprock or by floodwater supplied by sinking streams. Most hypogenic caves involve deep sources of aggressiveness. Transverse hypogenic cave origin is a recently proposed concept in which groundwater of mainly meteoric origin rises across strata in the distal portions of large flow systems, to form mazes in soluble rock sandwiched between permeable but insoluble strata. The distinction between maze types is debated and is usually based on examination of diagnostic cave features and relation of caves to their regional setting. In this paper, the principles of mass transfer are applied to clarify the limits of each model, to show how cave origin is related to groundwater discharge, dissolution rate, and time. The results show that diffuse infiltration and floodwater can each form maze caves at geologically feasible rates (typically within 500 ka). Transverse hypogenic mazes in limestone, to enlarge significantly within 1 Ma, require an unusually high permeability of the non-carbonate beds (generally ≥ 10-4 cm/s), large discharge, and calcite saturation no greater than 90%, which is rare in deep diffuse flow in sedimentary rocks. Deep sources of aggressiveness are usually required. The origin of caves by transverse hypogenic flow is much more favorable in evaporite rocks than in carbonate rocks.

  17. Exposure to radon in Australian tourist caves

    International Nuclear Information System (INIS)

    Solomon, S.B.; Langroo, R.; Lyons, R.G.

    1994-01-01

    In 1991 the International Commission on Radiological Protection(ICRP) produced guidelines and recommendations dealing with workplace exposure to elevated background radiation, in particular, the risk associated with the inhalation of radon and radon progeny. An intervention level of 1000 Bq m -3 has been proposed. Australia has over 40 tourist caves, under the management of the various State Departments or private groups. The limited data available on radon levels in Australian caves would suggest that some of these caves may be in excess of the proposed intervention level, thus presenting a potential health risk for the cave guides. This paper summarises the current information on radon in Australian caves and describes the proposed methodologies to be used for a Worksafe Australia-funded survey of radon levels in Tourist caves within Australia. This survey is to be carried out jointly by researchers at the Australian Radiation Laboratory, University of Auckland and the University of Sydney, during 1994 and 1995. 7 refs., 3 tabs

  18. Eleven bones: More fossil remains of Cave Lions and Cave Hyaenas from the North Sea area

    NARCIS (Netherlands)

    Bosscha Erdbrink, D.P.

    1983-01-01

    Six fossil Cave Lion bones and five fossil Cave Hyaena bones are described. One lion bone and one hyaena bone were dredged from the Westerschelde ( = Western Scheldt, southwestern part of the Netherlands). The other specimens were recovered from the bottom of the North Sea, in the area West and

  19. Millipedes (Diplopoda of twelve caves in Western Mecsek, Southwest Hungary

    Directory of Open Access Journals (Sweden)

    Angyal, D.

    2013-11-01

    Full Text Available Twelve caves of Western Mecsek, Southwest Hungary were examined between September 2010 and April 2013from the millipede (Diplopoda faunistical point of view. Ten species were found in eight caves, which consistedeutroglophile and troglobiont elements as well. The cave with the most diverse fauna was the Törökpince Sinkhole, while thetwo previously also investigated caves, the Abaligeti Cave and the Mánfai-kőlyuk Cave provided less species, which couldbe related to their advanced touristic and industrial utilization.

  20. The Mammoth Cave system, Kentucky, USA; El sistema de la Mammoth Cave, Kentucky, EE.UU

    Energy Technology Data Exchange (ETDEWEB)

    Palmer, A. N.

    2016-07-01

    Mammoth Cave is the main attraction of Mammoth Cave National Park. For several decades it has been the longest known cave in the world and currently contains 652 km in 2016 of surveyed passages. It is located in the heart of an extensive karst plateau, in which the stratal dip averages only one degree. The cave is part of a drainage basin of more than 200 km{sup 2}. The cave has been known to local inhabitants for several millennia and contains a rich trove of archaeological and historical artifacts. It contains many speleo biota including several rare and endangered species and has been designated a World Heritage Site and an International Biosphere Reserve (UNESCO). Its many passage levels and sediments contain a record of the fluvial history of most of south-eastern North America. (Author)

  1. The show cave of Diros vs. wild caves of Peloponnese, Greece - distribution patterns of Cyanobacteria

    Directory of Open Access Journals (Sweden)

    Vasiliki Lamprinou

    2014-09-01

    Full Text Available The karst cave ‘Vlychada’of Diros, one of the oldest show caves in Peloponnese, sustains extended phototrophic biofilms on various substrata – on rocks inside the cave including speleothems, and especially near the artificial lighting installation (‘Lampenflora’. After a survey of the main abiotic parameters (Photosynthetically Active Radiation -PAR, Temperature -T, Relative Humidity -RH, Carbon Dioxide -CO2 three clusters of sampling sites were revealed according to Principal Component Analysis (PCA: i the water gallery section predominately influenced by CO2, ii the dry passages influenced by RH and PAR, and iii the area by the cave exit at the dry section influenced by temperature. The collected samples from the water gallery section and the dry passages of the cave revealed a total of 43 taxa of Cyanobacteria, with the unicellular/colonial forms being the most abundant. The applied non-metric Multi-dimensional Scaling Ordination (nMDS of the cumulative species composition showed a clear distinction between the water gallery section and the dry passages of the cave. Further comparison with previous data from other wild caves of Peloponnese (‘Kastria’, ‘Francthi’, and ‘Selinitsa’ was conducted revealing a distinction between the show cave and the wild ones. Apart from the human impact on cave ecosystems – through aesthetic alteration (‘greening’ of cave decorations by the ‘Lampenflora’, and by the cleaning treatments and restoration projects on the speleothems – identification of the organisms constituting the ‘Lampenflora’ might provide taxonomically and ecologically significant taxa.

  2. Dating the Lascaux cave gour formation

    International Nuclear Information System (INIS)

    Genty, D.; Touma, M.; Konik, S.; Konik, S.; Valladas, H.; Hellstrom, J.; Moreau, C.; Dumoulin, J.P.; Nouet, J.; Dauphin, Y.; Weil, R.

    2011-01-01

    Lascaux Cave is renowned for its outstanding prehistoric paintings, strikingly well-preserved over about 18,000 yr. While stalagmites and stalactites are almost absent in the cave, there is an extensive calcite flow-stone that covered a large part of the cave until its opening for tourists during the 1950's. The deposit comprises a succession of calcite rims, or 'gours', which allowed seepage water to pond in large areas in the cave. Their possible role in preservation of the cave paintings has often been evoked, but until now this deposit has not been studied in detail. Here, we present 24 new radiocarbon accelerator mass spectrometry (AMS) and 6 uranium-thorium (U-Th) analyses from the calcite of the gours, 4 AMS 14 C dates from charcoals trapped in the calcite, and 4 AMS 14 C analyses on organic matter extracted from the calcite. Combining the calibrated 14 C ages obtained on charcoals and organic matter and U-Th ages from 14 C analyses made on the carbonate, has allowed the calculation of the dead carbon proportion (dcp) of the carbonate deposits. The latter, used with the initial atmospheric 14 C activities reconstructed with the new IntCal09 calibration data, allows high-resolution age estimation of the gour calcite samples and their growth rates. The carbonate deposit grew between 9530 and 6635 yr cal BP (for dcp = 10.7 ± 1.8%; 2 s) or between 8518 and 5489 yr cal BP (for dcp = 20.5 ± 1.9%; 2 s). This coincides with humid periods that can be related to the Atlantic period in Europe and to Sapropel 1 in the eastern Mediterranean Sea. However, geomorphological changes at the cave entrance might also have played a role in the gour development. In the 1940's, when humans entered the cave for the first time since its prehistoric occupation, the calcite gours had already been inactive for several thousand years. (authors)

  3. Journal bearing

    Science.gov (United States)

    Menke, John R.; Boeker, Gilbert F.

    1976-05-11

    1. An improved journal bearing comprising in combination a non-rotatable cylindrical bearing member having a first bearing surface, a rotatable cylindrical bearing member having a confronting second bearing surface having a plurality of bearing elements, a source of lubricant adjacent said bearing elements for supplying lubricant thereto, each bearing element consisting of a pair of elongated relatively shallowly depressed surfaces lying in a cylindrical surface co-axial with the non-depressed surface and diverging from one another in the direction of rotation and obliquely arranged with respect to the axis of rotation of said rotatable member to cause a flow of lubricant longitudinally along said depressed surfaces from their distal ends toward their proximal ends as said bearing members are rotated relative to one another, each depressed surface subtending a radial angle of less than 360.degree., and means for rotating said rotatable bearing member to cause the lubricant to flow across and along said depressed surfaces, the flow of lubricant being impeded by the non-depressed portions of said second bearing surface to cause an increase in the lubricant pressure.

  4. Solar activity influence on air temperature regimes in caves

    Science.gov (United States)

    Stoeva, Penka; Mikhalev, Alexander; Stoev, Alexey

    Cave atmospheres are generally included in the processes that happen in the external atmosphere as circulation of the cave air is connected with the most general circulation of the air in the earth’s atmosphere. Such isolated volumes as the air of caves are also influenced by the variations of solar activity. We discuss cave air temperature response to climate and solar and geomagnetic activity for four show caves in Bulgaria studied for a period of 46 years (1968 - 2013). Everyday noon measurements in Ledenika, Saeva dupka, Snezhanka and Uhlovitsa cave have been used. Temperatures of the air in the zone of constant temperatures (ZCT) are compared with surface temperatures recorded at meteorological stations situated near about the caves - in the towns of Vratsa, Lovech, Peshtera and Smolyan, respectively. For comparison, The Hansen cave, Middle cave and Timpanogos cave from the Timpanogos Cave National Monument, Utah, USA situated nearly at the same latitude have also been examined. Our study shows that the correlation between cave air temperature time series and sunspot number is better than that between the cave air temperature and Apmax indices; that t°ZCT is rather connected with the first peak in geomagnetic activity, which is associated with transient solar activity (CMEs) than with the second one, which is higher and connected with the recurrent high speed streams from coronal holes. Air temperatures of all examined show caves, except the Ledenika cave, which is ice cave show decreasing trends. On the contrary, measurements at the meteorological stations show increasing trends in the surface air temperatures. The trend is decreasing for the Timpanogos cave system, USA. The conclusion is that surface temperature trends depend on the climatic zone, in which the cave is situated, and there is no apparent relation between temperatures inside and outside the caves. We consider possible mechanism of solar cosmic rays influence on the air temperatures in caves

  5. Cave Tourism: The Potential of Asar Cave as a Natural Tourism Asset at Lenggong Valley, Perak

    Directory of Open Access Journals (Sweden)

    Rindam Main

    2014-01-01

    Full Text Available The Lenggong Valley, from a standpoint of natural tourism research, presents strengths, weaknesses, opportunities and challenges that can be utilized to help increase the opportunities for the local community to increase their standard of living. Asar Cave comprises one of the caves that are found in Lenggong. A series of external studies have been done on Asar Cave in order to measure its potential for natural tourism in Lenggong. The objective of this study is to discuss caves as a natural resource that has great potential in the growth of the economy of the residents of the Lenggong Valley. Marketing caves as a source of nature tourism helps the government’s achievements in National Key Result Areas, apart from being a form of environmental control as well as helping to increase awareness about environmental education, specifically those associated with caves. The research results find that SWOT analysis presents huge potential for caves to become a source of nature tourism development in Lenggong. Great potential can also be seen from a standpoint of increasing the standard of living of its residents through their involvement in the tourism sector based on local natural assets.

  6. Črna Jama as a cold air trap cave within Postojna Cave, Slovenia

    Science.gov (United States)

    Šebela, Stanka; Turk, Janez

    2017-10-01

    Črna Jama is the coldest section of cave within the Postojna Cave System. Mean annual air temperatures at the Črna Jama 2 site are 5.6 °C (2015) and 5.7 °C (2016), and at the Črna Jama 3 site 7.1 °C (2015) and 7.2 (2016), whereas the mean external air temperature was 10.3 °C (2015) and 10.0 °C (2016). In Lepe Jame, the passage most heavily visited by tourists, the mean cave-air temperature is 10.7 °C (2014-2017). Črna Jama exhibits winter and summer temperature regimes. During warm periods (Tcave Tout), ventilation takes place and dense, cold, outside air sinks into Črna Jama because of the favourable cave entrance morphology. Recent Črna Jama air temperature data (2014-2017) indicate a < 0.5 °C higher temperature than that recorded in historical data since 1933. Črna Jama is the most appropriate place within the Postojna Cave System to study long-term climatic changes. There are hardly any tourist visits to the cave, and human impacts on the cave climate are essentially reduced.

  7. Cave dwellings in the Mediterranean basin

    Directory of Open Access Journals (Sweden)

    Viedma Urdiales Eugenia María

    2011-01-01

    Full Text Available The construction and use of subterranean caves for different functions has been relatively commonplace throughout history in different regions around the world, especially in the Mediterranean basin. Some of them are still standing at the beginning of the 21st century, and are a good example of adaptation to the geographic environment, and a part of the historical heritage. Following a short overview of the different Mediterranean countries, this work pays special attention to the present use of caves as dwelling spaces in Italy, and particularly in Spain where the caves are currently in an interesting process of renovation to meet the needs of the present population. This process is helping to boost the local economy, and it is funded by both private and public sources in several towns in Andalusia (Spain.

  8. Radon in New Zealand tourist caves

    International Nuclear Information System (INIS)

    Lyons, R.G.; Solomon, S.B.; Langroo, R.

    1998-01-01

    Seasonal average radon concentrations in 112 sites in 22 NZ tourist caves have been measured using track etch detectors over an annual cycle. Values ranged from -3 to nearly 10,000 Bq m -3 . Seasonal variation was also very marked with factors of over 50 for the same site in different seasons being recorded. Thirty six percent of the sites exceeded the ICRP guideline of 1000 Bq m -3 at which action to reduce exposure is recommended. Caves are fragile ecological and chemical systems, therefore, may be seriously adversely affected by standard techniques to reduce radon concentrations. They are also complex physical systems, and an understanding of the principles and parameters governing cave aerodynamics is essential when considering options to reduce exposure. This paper discusses possible causes for variations in radon concentrations observed in this study and the implications for viable actions

  9. Cryogenic cave calcite from several Central European caves: age, carbon and a genetic model

    Czech Academy of Sciences Publication Activity Database

    Žák, K.; Urban, J.; Cílek, Václav; Hercman, H.

    2004-01-01

    Roč. 206, 1/2 (2004), s. 119-136 ISSN 0009-2541 R&D Projects: GA ČR(CZ) GA205/02/0449 Keywords : cryogenic calcite * periglacial zone Subject RIV: DB - Geology ; Mineralogy Impact factor: 3.174, year: 2004

  10. GAS BEARING

    Science.gov (United States)

    Skarstrom, C.W.

    1960-09-01

    A gas lubricated bearing for a rotating shaft is described. The assembly comprises a stationary collar having an annular member resiliently supported thereon. The collar and annular member are provided with cooperating gas passages arranged for admission of pressurized gas which supports and lubricates a bearing block fixed to the rotatable shaft. The resilient means for the annular member support the latter against movement away from the bearing block when the assembly is in operation.

  11. Grizzly bear

    Science.gov (United States)

    Schwartz, C.C.; Miller, S.D.; Haroldson, M.A.; Feldhamer, G.; Thompson, B.; Chapman, J.

    2003-01-01

    The grizzly bear inspires fear, awe, and respect in humans to a degree unmatched by any other North American wild mammal. Like other bear species, it can inflict serious injury and death on humans and sometimes does. Unlike the polar bear (Ursus maritimus) of the sparsely inhabited northern arctic, however, grizzly bears still live in areas visited by crowds of people, where presence of the grizzly remains physically real and emotionally dominant. A hike in the wilderness that includes grizzly bears is different from a stroll in a forest from which grizzly bears have been purged; nighttime conversations around the campfire and dreams in the tent reflect the presence of the great bear. Contributing to the aura of the grizzly bear is the mixture of myth and reality about its ferocity. unpredictable disposition, large size, strength, huge canines, long claws, keen senses, swiftness, and playfulness. They share characteristics with humans such as generalist life history strategies. extended periods of maternal care, and omnivorous diets. These factors capture the human imagination in ways distinct from other North American mammals. Precontact Native American legends reflected the same fascination with the grizzly bear as modern stories and legends (Rockwell 1991).

  12. Diurnal Variation of Radon Concentration in the Postojna Cave

    International Nuclear Information System (INIS)

    Gregoric, A.; Vaupotic, J.

    2011-01-01

    Postojna Cave, with 20 km of galleries, is the longest known cave system and also the largest of about 20 show caves in Slovenia and one of the most visited show caves in the world. It is well known that high concentrations of radon are common in karstic caves, although quantities of uranium (238U) in limestone are rather low. The reason for this is low natural ventilation of the underground cavities. Tectonic faults constitute an additional source of radon. Variations of radon concentration in cave air arise from a balance of the emission from cave surfaces and drip waters, decay in cave air, and exchange with the outside atmosphere. Because of its elevated radon concentrations, Postojna Cave has been under permanent radon survey since 1995. The influence of meteorological conditions on the radon levels and their temporal variations depends mostly on the shape of the cave, and the number and directions of cracks, corridors and fissures connecting the cave rooms with the outside atmosphere. The driving force for air movement in horizontal caves, and thus the inflow of fresh air and release of the cave air to the atmosphere, is the temperature difference between the cave air and outdoors, which causes seasonal pattern of radon concentration in the cave with high levels in summer and low in winter. However, on a daily scale different behaviour of radon can be observed at different locations in the cave. In this paper diurnal variation of radon concentration at two locations is presented and discussed. Postojna Cave is a horizontal cave with a stable yearly temperature around 10 degrees of @C. Continuous measurements of radon concentration were carried out from 2005 to 2010 at two locations along the guided tourist trail. Radon concentration was measured with Radim 5 WP monitors (SMM Company, Prague, Czech Republic) with sampling frequency once an hour. The evaluation of five-year radon monitoring at two sites in the Postojna Cave reveals significant diurnal and

  13. {sup 14}C AMS dating Yongcheon cave

    Energy Technology Data Exchange (ETDEWEB)

    Lee, J.H., E-mail: jefflee@snu.ac.kr [AMS Lab., NCIRF, Seoul National University, Seoul 151-742 (Korea, Republic of); Choe, K. [AMS Lab., NCIRF, Seoul National University, Seoul 151-742 (Korea, Republic of); Kim, J.C. [Dept. of Physics and Astronomy, Seoul National University, Seoul 151-742 (Korea, Republic of); Choi, S.H.; Kang, J.; Song, S.; Song, Y.M. [AMS Lab., NCIRF, Seoul National University, Seoul 151-742 (Korea, Republic of); Jang, J.G. [Jeju National Museum, Jeju 690-782 (Korea, Republic of)

    2013-01-15

    The biggest island in South Korea is Jeju Island, which lies 80 km south of the mainland and has one shield volcano, Mt. Halla. The volcanic island and its lava tubes were added to the world heritage list by UNESCO in 2007. Among the many lava tubes on the island, a unique cave had been accidentally found in 2005 while some workers were replacing a telephone pole. Until the discovery, it had been completely isolated from the outside by naturally-built sand blocks. Yongcheon cave is a lime-decorated lava tube showing both the properties of a volcanic lava tube and a limestone cave. This cave, about 3 km in length, is acknowledged to be the best of this type in the world and includes a large clean-water lake, lava falls, and richly developed speleothems inside it. Even though there is archaeological evidence from well preserved pottery that ancient people entered this place, the preservation of artifacts was ensured by a geological change that made later entrance difficult. We have collected charcoal samples scattered around the cave and dated them using AMS. Ages were in the range of ca. 1570-1260 BP (A.D. 340-880) and this corresponds to the Ancient Three Kingdoms and the Unified Silla era in Korean history. The {sup 14}C AMS measurement results presented in this paper on wood charcoal provide precise dates which will be very useful not only to clarify the nature of human activities in this cave but also to provide reference dates when comparing other dating methods.

  14. 14C AMS dating Yongcheon cave

    International Nuclear Information System (INIS)

    Lee, J.H.; Choe, K.; Kim, J.C.; Choi, S.H.; Kang, J.; Song, S.; Song, Y.M.; Jang, J.G.

    2013-01-01

    The biggest island in South Korea is Jeju Island, which lies 80 km south of the mainland and has one shield volcano, Mt. Halla. The volcanic island and its lava tubes were added to the world heritage list by UNESCO in 2007. Among the many lava tubes on the island, a unique cave had been accidentally found in 2005 while some workers were replacing a telephone pole. Until the discovery, it had been completely isolated from the outside by naturally-built sand blocks. Yongcheon cave is a lime-decorated lava tube showing both the properties of a volcanic lava tube and a limestone cave. This cave, about 3 km in length, is acknowledged to be the best of this type in the world and includes a large clean-water lake, lava falls, and richly developed speleothems inside it. Even though there is archaeological evidence from well preserved pottery that ancient people entered this place, the preservation of artifacts was ensured by a geological change that made later entrance difficult. We have collected charcoal samples scattered around the cave and dated them using AMS. Ages were in the range of ca. 1570-1260 BP (A.D. 340–880) and this corresponds to the Ancient Three Kingdoms and the Unified Silla era in Korean history. The 14 C AMS measurement results presented in this paper on wood charcoal provide precise dates which will be very useful not only to clarify the nature of human activities in this cave but also to provide reference dates when comparing other dating methods.

  15. Chemical deposits in volcanic caves of Argentina

    Directory of Open Access Journals (Sweden)

    Carlos Benedetto

    1998-01-01

    Full Text Available During the last Conference of the FEALC (Speleological Federation of Latin America and Caribbean Islands which was held in the town of Malargue, Mendoza, in February 1997, two volcanic caves not far from that town were visited and sampled for cave mineral studies. The first cave (Cueva del Tigre opens close to the Llancanelo lake, some 40 kms far from Malargue and it is a classical lava tube. Part of the walls and of the fallen lava blocks are covered by white translucent fibres and grains. The second visited cave is a small tectonic cavity opened on a lava bed some 100 km southward of Malargue. The cave “El Abrigo de el Manzano” is long no more than 10-12 meters with an average width of 3 meters and it hosts several bird nests, the larger of which is characterized by the presence of a relatively thick pale yellow, pale pink flowstone. Small broken or fallen samples of the secondary chemical deposits of both these caves have been collected in order to detect their mineralogical composition. In the present paper the results of the detailed mineralogical analyses carried out on the sampled material are shortly reported. In the Cueva del Tigre lava tube the main detected minerals are Sylvite, Thenardite, Bloedite and Kieserite, all related to the peculiar dry climate of that area. The flowstone of “El Abrigo de el Manzano” consists of a rather complex admixture of several minerals, the large majority of which are phosphates but also sulfates and silicates, not all yet identified. The origin of all these minerals is related to the interaction between bird guano and volcanic rock.

  16. Dating Petroglyphs from Fugoppe Cave, Japan

    Directory of Open Access Journals (Sweden)

    Masaru Ogawa

    2014-01-01

    Full Text Available For over 20 years, I have tried to establish a relative date for petroglyphs in Fugoppe Cave, Japan. Unsuspected amidst debris accumulating from about 1300 years ago, the petroglyphs were rediscovered accidentally in 1950. From an analysis of petroglyphs on fallen rocks scattered randomly on the site floor, I argue that the artworks date from ca.1900 years ago. The cave itself, formed by wave action, saw its main occupation by pottery-making people from 1700–1500 years ago; although the petroglyphs on the rock walls predated their occupation, it seems unlikely that the occupants attached any meaning to them.

  17. Features of deep cave sediments: their influence on fossil preservation

    Directory of Open Access Journals (Sweden)

    Cobo, R.

    2003-08-01

    Full Text Available We analyse how physical and chemical deep-cave sediment features preserve the morphological and geochemical characteristics of paleontological materials. Detrital sediment chemistry and clast size are fundamental because they provide a soft, impervious and plastic environment in which fossil remains are transported with minimal erosion. Sediment mineralogy provides a carbonate- and phosphate-buffered environment in which molecules of biological origin hydrolyze slower than in open-air environments or even at cave entrance sites. Because permafrost did not develop in the Iberian Peninsula (at least at the altitudes of inhabited caves, sediment desiccation never took place. In addition, sediment -pores were not aerated, which protected fossil remains from air (oxygen-linked weathering. The annual-temperature variation inside sediment was negligible, which contributed to amino acid racemization dating. Collagen amino acid and amino acid racemization analysis of cave bear and man samples from cave sediments dated from different Oxygen Isotope Stages (4": Sidrón, Amutxate, Troskaeta, El Toll, Coro Tracito, Ekain, Lezetxiki, La Pasada, Eirós; 5": Reguerillo and Arrikrutz; 6"-7": Sima de los Huesos demonstrate that important amounts of almost intact collagen still remain in teeth dentine. Fossil DNA search seems to be very promising.En este trabajo se analiza el papel que juegan las características físicas y químicas de los sedimentos de galerías profundas de cuevas en la preservación de los caracteres morfológicos y paleobiomoleculares del material paleontológico incluido en dichos sedimentos. Los aspectos geoquímicos y de tamaño de grano del sedimento son críticos: las características generan un medio blando, plástico e impermeable que permite el transporte -mecánico sin grave deterioro del material (en coladas de barro; las características químicas mineralogía del sediment* proporcionan un ambiente con tampón fosfatado

  18. Investigation of clay sediments and bedrock morphology in caves with seismic traveltime tomography: an application at Alepotrypa Cave (Diros, Greece

    Directory of Open Access Journals (Sweden)

    Lazaros Polymenakos

    2017-01-01

    Full Text Available The deposition of unconsolidated clay sediments in caves, in relation to the buried morphology of the karstic conduit, are important parameters for the study of cave evolution. We introduce the application of an active seismic imaging technique to investigate the clay deposits and bedrock morphology in caves. Seismic traveltime tomography, applied for the first time in cave studies, can assist with the interpretation of cave geomorphology. Utilizing the P-wave velocity contrast between the clay sediments and the surrounding rock mass, we map the buried rock surface and significant sediment interfaces and provide an estimate of the sediment thickness and volume. Our study focuses on the Alepotrypa Cave located in Diros (Peloponnese, Greece, revealing important information for the evolution of the cave. The proposed technique could be applied in caves with significant clay deposits, in order to constrain the clay volume and reconstruct the buried floor shape of the cave. The technique exploits fully the ground morphology and access points in a cave, so it is suitable for a detailed three-dimensional exploration of cave deposits and the underlying cave morphology.

  19. The importance of ants in cave ecology, with new records and behavioral observations of ants in Arizona caves

    Directory of Open Access Journals (Sweden)

    Robert B. Pape

    2016-09-01

    Full Text Available The importance of ants as elements in cave ecology has been mostly unrecognized. A global list of ant species recorded from caves, compiled from a review of existing literature, is presented. This paper also reviews what is currently known about ants occurring in Arizona (USA caves. The diversity and distribution represented in these records suggests ants are relatively common cave visitors (trogloxenes. A general utilization of caves by ants within both temperate and tropical latitudes may be inferred from this combined evidence. Observations of ant behavior in Arizona caves demonstrate a low level and sporadic, but persistent, use of these habitats and their contained resources by individual ant colonies. Documentation of Neivamyrmex sp. preying on cave-inhabiting arthropods is reported here for the first time. Observations of hypogeic army ants in caves suggests they may not penetrate to great vertical depth in search of prey, but can be persistent occupants in relatively shallow, horizontal sections of caves where they may prey on endemic cave animals. First cave records for ten ant species are reported from Arizona caves. These include two species of Neivamyrmex (N. nigrescens Cresson and Neivamyrmex sp.; Formicidae: Dorylinae, four myrmicines (Pheidole portalensis Wilson, Pheidole cf. porcula Wheeler, Solenopsis aurea Wheeler and Stenamma sp. Westwood, one dolichoderine (Forelius keiferi Wheeler and three formicines (Lasius arizonicus Wheeler, L. sitiens Wilson, and Camponotus sp. Mayr.

  20. Trace and macro elements in the femoral bone as indicators of long-term environmental exposure to toxic metals in European brown bear (Ursus arctos) from Croatia.

    Science.gov (United States)

    Lazarus, Maja; Orct, Tatjana; Reljić, Slaven; Sedak, Marija; Bilandžić, Nina; Jurasović, Jasna; Huber, Đuro

    2018-05-21

    We explored the long-term accumulation of aluminium, strontium, cadmium and lead in the compact and trabecular bone of the femoral epiphysis, metaphysis and diaphysis in 41 brown bears (Ursus arctos) from Croatia. Also, we assessed their influence on macro and trace elements (sodium, magnesium, phosphorus, potassium, calcium, manganese, iron, cobalt, copper, zinc and barium) in bears' bone. There were no sex differences in element levels in general, while age was associated with bone length and levels of all elements, except for cadmium. Elements had different levels depending on the part of the bone sampled. More pronounced differences were observed between the compact and trabecular regions, with higher levels of majority of elements found in compact bone. Moderate to high associations (Spearman coefficient, r S  = 0.59-0.97) were confirmed between calcium and potassium, magnesium, phosphorus, manganese, cobalt, zinc, strontium and lead. Lead levels in the bone were below those known to cause adverse health effects, but in 4 of 41 animals they exceeded baseline levels for domestic animals. The femoral bone of the brown bear reflected the accumulative nature of lead and strontium well, as it did the impairment of bone-forming essential element levels associated with these two elements. However, the distribution pattern of elements along the bone was not uniform, so additional care should be taken when choosing on the part of the bone sampled.

  1. Management of brown bears (Ursus arctos) in Europe.

    OpenAIRE

    Klenzendorf, Sybille A.

    1997-01-01

    Management of Brown Bears (Ursus arctos) in Europe. Sybille A. Klenzendorf (Abstract) Successful conservation of brown bears (Ursus arctos) in Europe is associated with public acceptance of damages caused by bears. Recent increases in sheep depredation and beehive damage in central Austria resulted in the deaths of two bears there. Since bear numbers are low in most European populations, alternatives to the elimination of problem bears associated with dam...

  2. Cryogenic Minerals in Caves of the Vizhay River (Northern Urals

    Directory of Open Access Journals (Sweden)

    E. P. Bazarova

    2018-03-01

    Full Text Available New information on the cryogenic mineral formations at the two Vizhay River caves (Northern Urals is given.   Calcite with the insignificant gypsum admixture predominates in the cryogenic material composition from both caves. In addition, the metastable phases of calcite, such as monohydrocalcite and ikaite were found. In the Saksofon Cave, calcite forms both spherulites and complanate grains. In Lednikovaya Cave, the major part of cryomaterial is presented by spherulites, which may suggests the significant supersaturation of solution. In Lednikovaya Сave, the distinct concentric structure with the growth zones denotes the cryogenic material formation in a thin water film under the partial thawing of upper part of long-term ice mound in summer. In Saksofon Cave the growth zones in crystals are poorly developed that probably caused by the seasonal glaciation in the cave and cryogenic minerals are younger than those in the Lednikovaya Cave.

  3. Instrumenting caves to collect hydrologic and geochemical data: case study from James Cave, Virginia

    Science.gov (United States)

    Schreiber, Madeline E.; Schwartz, Benjamin F.; Orndorff, William; Doctor, Daniel H.; Eagle, Sarah D.; Gerst, Jonathan D.

    2015-01-01

    Karst aquifers are productive groundwater systems, supplying approximately 25 % of the world’s drinking water. Sustainable use of this critical water supply requires information about rates of recharge to karst aquifers. The overall goal of this project is to collect long-term, high-resolution hydrologic and geochemical datasets at James Cave, Virginia, to evaluate the quantity and quality of recharge to the karst system. To achieve this goal, the cave has been instrumented for continuous (10-min interval) measurement of the (1) temperature and rate of precipitation; (2) temperature, specific conductance, and rate of epikarst dripwater; (3) temperature of the cave air; and (4) temperature, conductivity, and discharge of the cave stream. Instrumentation has also been installed to collect both composite and grab samples of precipitation, soil water, the cave stream, and dripwater for geochemical analysis. This chapter provides detailed information about the instrumentation, data processing, and data management; shows examples of collected datasets; and discusses recommendations for other researchers interested in hydrologic and geochemical monitoring of cave systems. Results from the research, briefly described here and discussed in more detail in other publications, document a strong seasonality of the start of the recharge season, the extent of the recharge season, and the geochemistry of recharge.

  4. Helium Isotopes and Noble Gas Abundances of Cave Dripping Water in Three Caves in East Asia

    Science.gov (United States)

    Chen, A. T.; Shen, C. C.; Tan, M.; Li, T.; Uemura, R.; Asami, R.

    2015-12-01

    Paleo-temperature recorded in nature archives is a critical parameter to understand climate change in the past. With advantages of unique inert chemical characteristics and sensitive solubilities with temperature, dissolved noble gases in speleothem inclusion water were recently proposed to retrieve terrestrial temperature history. In order to accurately apply this newly-developed speleothem noble gas temperature (NGT) as a reliable proxy, a fundamental issue about behaviors of noble gases in the karst should be first clarified. In this study, we measured noble gas contents in air and dripping water to evaluate any ratio deviation between noble gases. Cave dripping water samples was collected from three selected caves, Shihua Cave in northern China, Furong Cave in southwestern, and Gyukusen Cave in an island located in the western Pacific. For these caves are characterized by a thorough mixing and long-term storage of waters in a karst aquifer by the absence of seasonal oxygen isotope shifts. Ratios of dripping water noble gases are statistically insignificant from air data. Helium isotopic ratios in the dripping water samples match air value. The results indicate that elemental and isotopic signatures of noble gases from air can be frankly preserved in the epikarst and support the fidelity of NGT techniques.

  5. Is radon emission in caves causing deletions in satellite DNA sequences of cave-dwelling crickets?

    Directory of Open Access Journals (Sweden)

    Giuliana Allegrucci

    Full Text Available The most stable isotope of radon, 222Rn, represents the major source of natural radioactivity in confined environments such as mines, caves and houses. In this study, we explored the possible radon-related effects on the genome of Dolichopoda cave crickets (Orthoptera, Rhaphidophoridae sampled in caves with different concentrations of radon. We analyzed specimens from ten populations belonging to two genetically closely related species, D. geniculata and D. laetitiae, and explored the possible association between the radioactivity dose and the level of genetic polymorphism in a specific family of satellite DNA (pDo500 satDNA. Radon concentration in the analyzed caves ranged from 221 to 26,000 Bq/m3. Specimens coming from caves with the highest radon concentration showed also the highest variability estimates in both species, and the increased sequence heterogeneity at pDo500 satDNA level can be explained as an effect of the mutation pressure induced by radon in cave. We discovered a specific category of nuclear DNA, the highly repetitive satellite DNA, where the effects of the exposure at high levels of radon-related ionizing radiation are detectable, suggesting that the satDNA sequences might be a valuable tool to disclose harmful effects also in other organisms exposed to high levels of radon concentration.

  6. Food sources of selected terrestrial cave arthropods

    Czech Academy of Sciences Publication Activity Database

    Smrž, J.; Kováč, L.; Mikeš, J.; Šustr, Vladimír; Lukešová, Alena; Tajovský, Karel; Nováková, Alena; Režňáková, P.

    2015-01-01

    Roč. 16, č. 1 (2015), s. 37-46 ISSN 1768-1448 Grant - others:Vega(SK) 1/0139/09 Institutional research plan: CEZ:AV0Z60660521 Institutional support: RVO:60077344 Keywords : Acari * caves * Collembola * Diplopoda * feeding habits * Isopoda Subject RIV: EG - Zoology

  7. Measurements of Aerosol Characteristics in Skocjan Caves

    International Nuclear Information System (INIS)

    Jovanovic, P.

    2013-01-01

    Measurements of radon concentration and radon progeny concentration (attached and unattached) have been performed in Skocjan caves. In the same time also aerosol concentration (PM 10 ), aerosol size distribution with ten stage Hauke impactor and Scanning Mobility Particle Sizer - SMPS have been performed. The idea was to find impact of outer air and visitors to the aerosol characteristics of cave air. Measurements with impactor have been implemented in summer and winter period, with SMPS only in summer period. Radon concentrations ranged in winter period in region from 500 to 1000 Bq/m 3 , equilibrium factor was about 55 %. In summer period radon concentration increased up to 10 kBq/m 3 , equilibrium factor was about 45 %, and unattached fraction went up to 20 %. Measurements of aerosol size distribution show lower aerosol sizes in winter season (around 1 μm) and bigger aerosol sizes in summer season (around 3 - 6 μm). We could not find good correlation between unattached fraction and aerosol size distribution. Also we could not find clear impact of visitors to the air characteristics in cave. Probably our measuring location was too close to the entrance and the impact of outer air was too high. We will repeat measurements deeper in cave to find better results.(author)

  8. Transfer of environmental signals from the surface to the underground at Ascunsă Cave, Romania

    Science.gov (United States)

    Drăguşin, Virgil; Balan, Sorin; Blamart, Dominique; Lázár Forray, Ferenc; Marin, Constantin; Mirea, Ionuţ; Nagavciuc, Viorica; Orăşeanu, Iancu; Perşoiu, Aurel; Tîrlă, Laura; Tudorache, Alin; Vlaicu, Marius

    2017-10-01

    We present here the results of a 4-year environmental monitoring program at Ascunsă Cave (southwestern Romania) designed to help us understand how climate information is transferred through the karst system and archived by speleothems. The air temperature inside the cave is around 7 °C, with slight differences between the upper and lower parts of the main passage. CO2 concentrations in cave air have a seasonal signal, with summer minima and winter maxima. These might indicate the existence of an organic matter reservoir deep within the epikarst that continues to decompose over the winter, and CO2 concentrations are possibly modulated by seasonal differences in cave ventilation. The maximum values of CO2 show a rise after the summer of 2014, from around 2000 to about 3500 ppm, following a rise in surface temperature. Using two newly designed types of water-air equilibrators, we were able to determine the concentration of CO2 dissolved in drip water by measuring its concentration in the equilibrator headspace and then using Henry's law to calculate its concentration in water. This method opens the possibility of continuous data logging using infrared technology, without the need for costly and less reliable chemical determinations. The local meteoric water line (δ2H = 7.7 δ18O + 10.1), constructed using monthly aggregated rainfall samples, is similar to the global one, revealing the Atlantic as the strongly dominant vapor source. The deuterium excess values, as high as 17 ‰, indicate that precipitation has an important evaporative component, possibly given by moisture recycling over the European continent. The variability of stable isotopes in drip water is similar at all points inside the cave, suggesting that the monitored drip sites are draining a homogenous reservoir. Drip rates, as well as stable isotopes, indicate that the transfer time of water from the surface is on the order of a few days.

  9. Radon survey in caves from Mallorca Island, Spain

    Energy Technology Data Exchange (ETDEWEB)

    Dumitru, Oana A. [Department of Geology, Babeș-Bolyai University, Kogălniceanu 1, 400084 Cluj-Napoca (Romania); School of Geosciences, University of South Florida, 4202 E. Fowler Ave., NES 107 Tampa (United States); Onac, Bogdan P. [School of Geosciences, University of South Florida, 4202 E. Fowler Ave., NES 107 Tampa (United States); Fornós, Joan J. [Departament de Ciències de la Terra, Universitat de les Illes Balears, Crta. Valldemossa km 7.5, 07122 Palma (Mallorca) (Spain); Cosma, Constantin [Environmental Radioactivity and Nuclear Dating Center, Babeș-Bolyai University, Fântânele 30, 400294 Cluj-Napoca (Romania); Ginés, Angel; Ginés, Joaquín [Departament de Ciències de la Terra, Universitat de les Illes Balears, Crta. Valldemossa km 7.5, 07122 Palma (Mallorca) (Spain); Merino, Antoni [Grup Espeleològic de Llubí, Federació Balear d' Espeleologia, c/Uruguai s/n, Palma Arena, 07010 Palma, Illes Balears (Spain)

    2015-09-01

    This study reports radon concentration in the most representative caves of Mallorca, identifying those in which the recommended action level is exceeded, thus posing health risks. Two show caves (Campanet and Artà) and three non-touristic caves (Font, Drac, Vallgornera) were investigated. Data were collected at several locations within each cave for three different periods, from March 2013 to March 2014. Except for Vallgornera, where only one monitoring period was possible, and Artà in which low values were recorded throughout the year, a clear seasonal variability, with higher values during the warm seasons and lower during winter time is prominent. Radon concentrations differed markedly from one cave to another, as well as within the same cave, ranging from below detection limit up to 3060 Bq·m{sup −3}. The results of this study have significant practical implications, making it possible to provide some recommendation to cave administrators and other agencies involved in granting access to the investigated caves. - Highlights: • A survey of radon was carried out in caves from Mallorca, Spain using CR 39 detectors. • Three different seasons are covered: spring, summer, and winter. • Radon level ranges from below detection limit up to 3060 Bq·m{sup −3}. • Seasonal variation is evident (higher values in summer and lower during winter). • Particular recommendations were made to each cave administration.

  10. Fish mitigate trophic depletion in marine cave ecosystems.

    Science.gov (United States)

    Bussotti, Simona; Di Franco, Antonio; Bianchi, Carlo Nike; Chevaldonné, Pierre; Egea, Lea; Fanelli, Emanuela; Lejeusne, Christophe; Musco, Luigi; Navarro-Barranco, Carlos; Pey, Alexis; Planes, Serge; Vieux-Ingrassia, Jean Vincent; Guidetti, Paolo

    2018-06-15

    Dark marine habitats are often characterized by a food-limited condition. Peculiar dark habitats include marine caves, characterized by the absence of light and limited water flow, which lead to reduced fluxes of organic matter for cave-dwelling organisms. We investigated whether the most abundant and common cave-dwelling fish Apogon imberbis has the potential to play the role of trophic vector in Mediterranean marine caves. We first analysed stomach contents to check whether repletion changes according to a nycthemeral cycle. We then identified the prey items, to see whether they belong to species associated with cave habitats or not. Finally, we assessed whether A. imberbis moves outside marine caves at night to feed, by collecting visual census data on A. imberbis density both inside and outside caves, by day and by night. The stomach repletion of individuals sampled early in the morning was significantly higher than later in the day. Most prey were typical of habitats other than caves. A. imberbis was on average more abundant within caves during the day and outside during the night. Our study supports the hypothesis regarding the crucial trophic role of A. imberbis in connecting Mediterranean marine caves with external habitats.

  11. Book Review: Caves and Karst of the Yorkshire Dales

    Science.gov (United States)

    Westaway, Rob

    2015-10-01

    The British Cave Research Association (BCRA) is the research division of the British Caving Association (BCA), itself the principal society in Britain for those interested in caving, with activities including provision of training and safety certification for cavers and managing access to caves. Although some UK cave-related research is carried out by academics, this tends to be restricted to archaeological investigations of caves that have served as human habitations, and to be focused more on the occupants than the caves themselves. In contrast, most cave exploration is undertaken as a leisure activity, under the auspices of clubs affiliated to the BCA/BCRA, this being indeed virtually the only field of Earth science where amateur investigators can continue to make significant discoveries. Many cave explorers are also affiliated with academic researchers, such as managers of dating laboratories; the synergy between these two groups is highly productive, having resulted for instance in the discovery and exploration in recent years of the vast Ogof Draenen cave system in South Wales, which probably dates back to the Early Pleistocene (e.g., Farrant et al., 2014).

  12. Cryogenic cave carbonates from the Cold Wind Cave, Nízke Tatry Mountains, Slovakia: Extending the age range of cryogenic cave carbonate formation to the Saalian

    Directory of Open Access Journals (Sweden)

    Zak K.

    2009-07-01

    Full Text Available Cold Wind Cave, located at elevations ranging between 1,600 and 1,700 m a. s. l. in the main range of the Nízke Tatry Mountains(Slovakia, is linked in origin with the adjacent Dead Bats Cave. Together, these caves form a major cave system located within anarrow tectonic slice of Triassic sediments. Both caves have undergone complex multiphase development. A system of sub-horizontalcave levels characterized by large, tunnel-like corridors was formed during the Tertiary, when elevation differences surroundingthe cave were less pronounced than today. The central part of the Nízke Tatry Mountains, together with the cave systems, wasuplifted during the Neogene and Lower Pleistocene, which changed the drainage pattern of the area completely. The formation ofnumerous steep-sloped vadose channels and widespread cave roof frost shattering characterized cave development throughout theQuaternary.In the Cold Wind Cave, extensive accumulations of loose, morphologically variable crystal aggregates of secondary cave carbonateranging in size between less than 1 mm to about 35 mm was found on the surface of fallen limestone blocks. Based on the C andO stable isotope compositions of the carbonate (δ13C: 0.72 to 6.34 ‰, δ18O: –22.61 to –13.68 ‰ V-PDB and the negative relationbetween δ13C and δ18O, the carbonate crystal aggregates are interpreted as being cryogenic cave carbonate (CCC. Publishedmodels suggest the formation of CCC in slowly freezing water pools, probably on the surface of cave ice, most probably duringtransitions from stadials to interstadials. Though the formation of these carbonates is likely one of the youngest events in thesequence of formation of cave sediments of the studied caves, the 230Th/234U ages of three samples (79.7±2.3, 104.0±2.9, and180.0±6.3 ka are the oldest so far obtained for CCC in Central Europe. This is the first description of CCC formation in one caveduring two glacial periods (Saalian and Weichselian.

  13. Contextualizing Cave Maps as Geospatial Information: Case Study of Indonesia

    Science.gov (United States)

    Reinhart, H.

    2017-12-01

    Caves are the result of solution processes. Because they are happened from geochemical and tectonic activity, they can be considered as geosphere phenomena. As one of the geosphere phenomena, especially at karst landform, caves have spatial dimensions and aspects. Cave’s utilizations and developments are increasing in many sectors such as hydrology, earth science, and tourism industry. However, spatial aspects of caves are poorly concerned dues to the lack of recognition toward cave maps. Many stakeholders have not known significances and importance of cave maps in determining development of a cave. Less information can be considered as the cause. Therefore, it is strongly necessary to put cave maps into the right context in order to make stakeholders realize the significance of it. Also, cave maps will be officially regarded as tools related to policy, development, and conservation act of caves hence they will have regulation in the usages and applications. This paper aims to make the contextualization of cave maps toward legal act. The act which is used is Act Number 4 Year 2011 About Geospatial Information. The contextualization is done by scrutinizing every articles and clauses related to cave maps and seek the contextual elements from both of them. The results are that cave maps can be regarded as geospatial information and classified as thematic geospatial information. The usages of them can be regulated through the Act Number 4 Year 2011. The regulations comprised by data acquisition, database, authorities, surveyor, and the obligation of providing cave maps in planning cave’s development and the environment surrounding.

  14. Minerogenetic mechanisms occurring in the cave environment: an overview

    Directory of Open Access Journals (Sweden)

    Forti Paolo

    2011-07-01

    Full Text Available Perhaps man’s first motivation to explore caves, beyond using them as shelter, was the search for substances that were not availableelsewhere: most of them were minerals. However, for a long time it was believed that the cave environment was not very interestingfrom the mineralogical point of view. This was due to the fact that most cave deposits are normally composed of a singlecompound: calcium carbonate. Therefore, the systematic study of cave mineralogy is of only recent origin. However, although onlya limited number of natural cavities have been investigated in detail, about 350 cave minerals have already been observed, someof which are new to science. The presence of such unexpected richness is a direct consequence of the variety of rocks traversedby water or other fluids before entering a cave and the sediments therein. Different cave environments allow the development ofvarious minerogenetic mechanisms, the most important of which are double exchange reactions, evaporation, oxidation, hydrationdehydration,sublimation, deposition from aerosols and vapors, and segregation. The cave temperature and pH/Eh strictly controlmost of them, although some are driven by microorganisms. The cave environment, due to its long-term stability, can sometimesallow for the development of huge euhedral crystals, such as those found in the Naica caves (Mexico, but the presence of extremelysmall yet complex aggregates of different minerals is far more common. Future development in the field of cave mineralogy will likelybe focused mainly on hydrothermal and sulfuric-acid caves and on the role played by micro-organisms in controlling some of the mostimportant minerogenetic processes in caves.

  15. Pre-excavation studies of prehistoric cave sites by magnetic prospecting

    Science.gov (United States)

    Itkis., Sonia; Matskevich, Zinovii; Meshveliani, Tengiz

    2014-05-01

    lithic material to Mesolithic and Early Neolithic periods. The upper layer is ca 50 cm thick, consists of fine grey silt with few pebbles and includes numerous bones and lithic implements. In this layer two circular dense concentrations of charcoal, possibly fireplaces were discovered. Conclusions 1. The results of magnetic survey obtained in prehistoric cave sites in Israel and Georgia show the high efficiency of the magnetic method for revealing and detailed characterization of caves. 2. The presence of organic materials, e.g. bones, charcoals and ceramics in caves enhances magnetic contrast between non-magnetic bedrock and the cave's fill, increasing the potential of the magnetic method. 3. Revealing enhanced magnetization of soil within studied caves allowed us to develop an approach to reliable interpretation of magnetic data in studied areas References Bar-Oz, G., Belfer-Cohen, A, Meshvelliani, T., Jakeli, N., Matskevich, Z. and Bar-Yosef, O. 2009. Bear in mind: bear hunting in the Mesolithic of the Southern Caucasus, the case of Kotias Klde rockshelter, western Georgia. Archaeology, Ethnology and Anthropology of Eurasia 37 (1): 15-24. Dalan, R. A. and Banerjee, S. K. 1998. Solving archaeological problems using techniques of soil magnetism. Geoarchaeology: An International Journal, Vol. 13, No.1, pp.1-36. Fassbinder, J.W. E. , Stanijek, H. and Vali, H. 1990. Occurence of magnetic bacteria in soil. Nature 343, 161-163. Itkis, S. 2003. Magnetic Susceptibility Measurements of Soil: A Diagnostic Tool for Location of Human Activity Areas (Ch. 14) In: Khalaily, H. and Marder, O. (editors). The Neolithic Site of Abu Ghosh: The 1995 Excavations. IAA Reports, No.19. Jerusalem. p. 129-131. Itkis, S. 2011..Magnetic survey at Ramat Bet Shemesh. In: Dagan Y. (editor). The Ramat Bet Shemesh Regional Project: Landscapes of Settlement from the Paleolithic to the Ottoman Period, IAA Reports, No. 47, Israel Antiquites Authority, Jerusalem 2011, pp. 95-104. Itkis S.E and Eppelbaum L

  16. The magnesium isotope record of cave carbonate archives

    Science.gov (United States)

    Riechelmann, S.; Buhl, D.; Schröder-Ritzrau, A.; Riechelmann, D. F. C.; Richter, D. K.; Vonhof, H. B.; Wassenburg, J. A.; Geske, A.; Spötl, C.; Immenhauser, A.

    2012-11-01

    δ26Mg values of the German speleothems are shifted to higher values due to sampling in detrital layers (Mg-bearing clay minerals) of the speleothems. The data and their interpretation shown here highlight the potential but also the limitations of the magnesium isotope proxy applied in continental climate research. An obvious potential lies in its sensitivity for even subtle changes in soil-zone parameters, a hitherto rather poorly understood but extremely important component in cave archive research. Limitations are most obvious in the low resolution and high sample amount needed for analysis. Future research should focus on experimental and conceptual aspects including quantitative and well-calibrated leaching and precipitation experiments.

  17. The magnesium isotope record of cave carbonate archives

    Directory of Open Access Journals (Sweden)

    S. Riechelmann

    2012-11-01

    affecting soil zone activity and weathering balance. Several δ26Mg values of the Austrian and two δ26Mg values of the German speleothems are shifted to higher values due to sampling in detrital layers (Mg-bearing clay minerals of the speleothems. The data and their interpretation shown here highlight the potential but also the limitations of the magnesium isotope proxy applied in continental climate research. An obvious potential lies in its sensitivity for even subtle changes in soil-zone parameters, a hitherto rather poorly understood but extremely important component in cave archive research. Limitations are most obvious in the low resolution and high sample amount needed for analysis. Future research should focus on experimental and conceptual aspects including quantitative and well-calibrated leaching and precipitation experiments.

  18. Cave Entrance dependent Spore Dispersion of Filamentous Fungi Isolated from Various Sediments of Iron Ore Cave in Brazil: a colloquy on human threats while caving

    Directory of Open Access Journals (Sweden)

    Erika Linzi Silva Taylor

    2014-04-01

    Full Text Available Caves are stable environments with characteristics favoring the development of fungi. The fungal community present in a cave also includes pathogenic and opportunistic species out of which some are also served as energy sources in such energy stared ecosystems. Studies on microbial diversity and their role on such energy starved ecosystem are scarce. The present study was aimed to identify the cultivable filamentous fungi present in the various sediment of an iron ore cave and to recognize them as pathogenic and/or opportunistic species. Further the impact of cave entrance on the spore depositions on various distances dependent sediments were analyzed. The results suggest a diverse microbial community inhabiting the cave and an influence of cave entrance over spore deposition on various sediments. We counted a total of 4,549 filamentous fungi that included 34 species of 12 genera: Acremonium, Aspergillus, Cladosporium, Fusarium, Geotrichum, Paecilomyces, Purpureocillium, Penicillium, Torula, Trichoderma, Mucor and Rhizopus. A positive significant relation was observed between spore deposition and distance from cave entrance (p= 0.001. Areas of potential mycoses risks were recognized. This is the first study on microbiological community of an iron ore cave in the country.

  19. Hotspot mitigation in the StarCAVE

    KAUST Repository

    Rhee, Jordan; Schulze, Jurgen; DeFanti, Thomas A.

    2010-01-01

    Rear-projected screens such as those in Digital Light Projection (DLP) televisions suffer from an image quality problem called hot spotting, where the image is brightest at a point dependent on the viewing angle. In rear-projected mulit-screen configurations such as the StarCAVE at Calit2, this causes discontinuities in brightness at the edges where screens meet, and thus in the 3D image perceived by the user. In the StarCAVE we know the viewer's position in 3D space and we have programmable graphics hardware, so we can mitigate this effect by performing post-processing in the inverse of the pattern, yielding a homogenous image at the output. Our implementation improves brightness homogeneity by a factor of 4 while decreasing frame rate by only 1-3 fps.

  20. Hotspot mitigation in the StarCAVE

    KAUST Repository

    Rhee, Jordan

    2010-01-27

    Rear-projected screens such as those in Digital Light Projection (DLP) televisions suffer from an image quality problem called hot spotting, where the image is brightest at a point dependent on the viewing angle. In rear-projected mulit-screen configurations such as the StarCAVE at Calit2, this causes discontinuities in brightness at the edges where screens meet, and thus in the 3D image perceived by the user. In the StarCAVE we know the viewer\\'s position in 3D space and we have programmable graphics hardware, so we can mitigate this effect by performing post-processing in the inverse of the pattern, yielding a homogenous image at the output. Our implementation improves brightness homogeneity by a factor of 4 while decreasing frame rate by only 1-3 fps.

  1. Sensing Structures Inspired by Blind Cave Fish

    Science.gov (United States)

    McConney, Michael E.; Chen, Nannan; Lu, David; Anderson, Kyle D.; Hu, Huan; Liu, Chang; Tsukruk, Vladimir V.

    2009-03-01

    Blind cave fish, with degenerated non-functioning eyes, have evolved to ``see'' their hydrodynamic environment by using the flow receptors of the lateral line system. The hair-cell receptors are encapsulated in a hydrogel-like material, called a cupula, which increases the sensitivity of the hair-cell receptors by coupling their motion to the surrounding flowing media. We characterized the viscoelastic properties and of blind cave fish cupulae by using colloidal-probe spectroscopy in fluid. A photo-patternable hydrogel with similar properties was developed to mimic the fish receptor coupling structure. Flow-based measurements indicated that the hydrogels enhance drag through increased surface area, but also inherent material properties. These bio-inspired structures endowed micro-fabricated flow sensors with sensitivities rivaling that of fish.

  2. Calcium carbonate concretions in caves : an overview

    International Nuclear Information System (INIS)

    Gewelt, M.; Ek, C.

    1988-01-01

    The scientific work of the last twenty years on calcium carbonate cave deposits (dripstones and flowstones) is presented. Recent studies on speleothems composition, growth, age and paleoclimatic environment are examined. Main new results are related with the development of isotopic and radiometric dating methods. Increasing numbers of dates allow for statistical speleothem repartition studies which could be related with paleoclimates. Two new frequency curves of U-series ages data of speleothems are given. (M.C.B.)

  3. 76 FR 42654 - Endangered and Threatened Wildlife and Plants; Petition To List Grand Canyon Cave Pseudoscorpion

    Science.gov (United States)

    2011-07-19

    ... from 1977 to 1978. Eight caves were examined including Babylon Cave, Crystal Forest Cave, Land's End...) describes examining the walls, ceilings, and floors for animals and invertebrates. He identified 12...

  4. Calculating flux to predict future cave radon concentrations

    Czech Academy of Sciences Publication Activity Database

    Rowberry, Matthew David; Martí, Xavier; Frontera, C.; Van De Wiel, M.J.; Briestenský, Miloš

    2016-01-01

    Roč. 157, JUN (2016), 16-26 ISSN 0265-931X R&D Projects: GA MŠk LM2010008 Institutional support: RVO:67985891 ; RVO:68378271 Keywords : cave radon concentration * cave radon flux * cave ventilation * radioactive decay * fault slip * numerical modelling Subject RIV: DC - Siesmology, Volcanology, Earth Structure; BG - Nuclear, Atomic and Molecular Physics, Colliders (FZU-D) Impact factor: 2.310, year: 2016

  5. Depth Perception in Cave and Panorama

    DEFF Research Database (Denmark)

    Mullins, Michael; Strojan, Tadeja Zupancic

    2004-01-01

    This study compares aspects of spatial perception in a physical environment and its virtual representations in a CAVE and Panorama, derived from recent research. To measure accuracy of spatial perception, participants in an experiment were asked to look at identical objects in the three environme......, learning and training in virtual environments; in architectural education; and participatory design processes, in which the dialogue between real and imagined space may take place in virtual . reality environments...... environments and then locate them and identify their shape on scaled drawings.  Results are presented together with statistical analysis. In a discussion of the results, the paper addresses the two hypothetical assertions ? that depth perception in physical reality and its virtual representations in CAVE......This study compares aspects of spatial perception in a physical environment and its virtual representations in a CAVE and Panorama, derived from recent research. To measure accuracy of spatial perception, participants in an experiment were asked to look at identical objects in the three...

  6. Radiocarbon intercomparison program for Chauvet Cave

    International Nuclear Information System (INIS)

    Cuzange, M.T.; Delque-Kolic, E.; Oberlin, C.; Goslar, T.; Grootes, P.M.; Nadeau, M.J.; Higham, T.; Ramsey, C.B.; Kaltnecker, E.; Paterne, M.; Valladas, H.; Van der Plicht, J.; Van der Plicht, J.; Clottes, J.; Geneste, J.M.

    2007-01-01

    We present the first results of an accelerator mass spectrometry (AMS) radiocarbon intercomparison program on 3 different charcoal samples collected in one of the hearths of the Megaceros gallery of Chauvet Cave (Ardeche, France). This cave, rich in parietal decoration, is important for the study of the appearance and evolution of prehistoric art because certain drawings have been 14 C dated to the Aurignacian period at the beginning of the Upper Paleolithic. The new dates indicate an age of about 32,000 BP, which is consistent with this attribution and in agreement with the results from the same sector of the cave measured previously at the Laboratoire des Sciences du Climat et de l'Environnement (LSCE). Six laboratories were involved in the intercomparison. Samples were measured in 4 AMS facilities: Center for Isotope Research, Groningen University, the Netherlands; the Oxford Radiocarbon Accelerator Unit, UK; the Centre de datation par le carbone 14, Univ. Claude Bernard Lyon 1, France (measured by AMS facilities of Poznan University, Poland); and the LSCE, UMR CEA-CNRS-UVSQ, France (measured by the Leibniz-Labor of Christian-Albrechts-Universitat Kiel, Germany). (authors)

  7. An Investigation of Meromixis in Cave Pools, Lechuguilla Cave, New Mexico.

    Directory of Open Access Journals (Sweden)

    David B. Levy

    2008-07-01

    Full Text Available Chemical characteristics of permanent stratification in cave pools (meromixis may provide insight into the geochemical origin and evolution of cave pool waters. The objective of this study was to test the hypothesis that some pools in Lechuguilla Cave may be subject to ectogenic meromixis, where permanent chemical stratification is induced by input of relatively saline or fresh water from an external source. However, because organic C concentrations in Lechuguilla waters are low (typically 0.9 m, and are probably the result of localized and transient atmospheric CO2(g concentrations. At LOBG, an EC increase of 93 µS cm-1 at the 0.9-m depth suggests meromictic conditions which are ectogenic, possibly due to surface inflow of fresh water as drips or seepage into a pre-existing layer of higher salinity.

  8. Some deep caves in Biokovo Mountain (Croatia)

    Science.gov (United States)

    Garasic, Mladen; Garasic, Davor

    2014-05-01

    The investigation of 3 caves explored more than 1000 meters in depth in the Dinaric karst area in Croatia, has been in progress for a considerable period of time. These are complex speleological features situated in the longest mountain range of the Dinaric karst, i.e. at the Northern Velebit mountain range. In fact, these caves have been studied for over two decades now. The first one is a cave system of Lukina jama (Luke's Cave) - Trojama cave, which has been investigated until the depth of 1421 meters (Jalžić, 2007; Šmida, 1993). Its total length is 3731 meters and a new expedition will soon continue to investigate this pit through speleodiving in siphons. The second greatest cave by depth is Slovačka jama (Slovak Cave), 1320 meters in depth, with cave chanals measuring 5677 meters in total length. The third greatest cave by depth is the Cave system of Velebita, reaching down to 1026 m in depth, with the chanal length of 3176 meters (Bakšić, 2006a; 2006b). However, another 3 speleological sites, which can rightly be added to those deeper than 1000 m, have recently been discovered. These are three caverns that were discovered during construction of the Sveti Ilija Tunnel that passes through Mt. Biokovo, in the Dinaric karst area. These caverns undoubtedly point to the link with the ground surface, while the rock overburden above the tunnel in the zone where the caverns were discovered ranges from 1250 and 1350 meters. Bats from the ground surface were found in the caverns and, according to measurements, they are situated in the depth from 200 and 300 meters below the tunnel level. This would mean that the depth of these newly found caves ranges from 1450 and 1650 m, when observed from the ground surface. There are several hundreds of known caves in Biokovo, and the deepest ones discovered so far are Jama Mokre noge (Wet Feet Cave) 831 m in depth, and Jama Amfora (Amphora Cave) 788 m in depth (Bockovac, 1999; Bakšić & all, 2002; Lacković & all, 2001

  9. Discovery of a diverse cave flora in China

    Science.gov (United States)

    Wen, Fang

    2018-01-01

    Few studies document plants in caves. Our field observations of a widespread and seemingly angiosperm-rich cave flora in SW China lead us to test the following hypotheses, 1) SW China caves contain a diverse vascular plant flora, 2) that this is a relic of a largely absent forest type lacking endemic species, and 3) that the light environment plants occupy in caves is not distinct from non-cave habitats. To do so we surveyed 61 caves and used species accumulation curves (SAC) to estimate the total diversity of this flora and used a subsample of 14 caves to characterise the light environment. We used regional floras and existing conservation assessments to evaluate the conservation value of this flora. We used observations on human disturbance within caves to evaluate anthropogenic activities. Four-hundred-and-eighteen vascular plant species were documented with SACs predicting a total diversity of 529–846. Ninety-three percent of the species documented are known karst forest species, 7% are endemic to caves and 81% of the species are angiosperms. We demonstrate that the light environment in caves is distinct to that of terrestrial habitats and that a subset of the flora likely grow in the lowest light levels documented for vascularised plants. Our results suggest that the proportion of species threatened with extinction is like that for the terrestrial habitat and that almost half of the entrance caverns sampled showed signs of human disturbance. We believe that this is the first time that such an extensive sample of cave flora has been undertaken and that such a diverse vascular plant flora has been observed in caves which we predict occurs elsewhere in SE Asia. We argue that the cave flora is an extension of the karst forest understory present prior to catastrophic deforestation in the 20thC. We suggest that within SW China caves serve as both refuges and a valuable source of germplasm for the restoration of karst forest. We also propose that caves represent a

  10. Discovery of a diverse cave flora in China.

    Science.gov (United States)

    Monro, Alexandre K; Bystriakova, Nadia; Fu, Longfei; Wen, Fang; Wei, Yigang

    2018-01-01

    Few studies document plants in caves. Our field observations of a widespread and seemingly angiosperm-rich cave flora in SW China lead us to test the following hypotheses, 1) SW China caves contain a diverse vascular plant flora, 2) that this is a relic of a largely absent forest type lacking endemic species, and 3) that the light environment plants occupy in caves is not distinct from non-cave habitats. To do so we surveyed 61 caves and used species accumulation curves (SAC) to estimate the total diversity of this flora and used a subsample of 14 caves to characterise the light environment. We used regional floras and existing conservation assessments to evaluate the conservation value of this flora. We used observations on human disturbance within caves to evaluate anthropogenic activities. Four-hundred-and-eighteen vascular plant species were documented with SACs predicting a total diversity of 529-846. Ninety-three percent of the species documented are known karst forest species, 7% are endemic to caves and 81% of the species are angiosperms. We demonstrate that the light environment in caves is distinct to that of terrestrial habitats and that a subset of the flora likely grow in the lowest light levels documented for vascularised plants. Our results suggest that the proportion of species threatened with extinction is like that for the terrestrial habitat and that almost half of the entrance caverns sampled showed signs of human disturbance. We believe that this is the first time that such an extensive sample of cave flora has been undertaken and that such a diverse vascular plant flora has been observed in caves which we predict occurs elsewhere in SE Asia. We argue that the cave flora is an extension of the karst forest understory present prior to catastrophic deforestation in the 20thC. We suggest that within SW China caves serve as both refuges and a valuable source of germplasm for the restoration of karst forest. We also propose that caves represent a

  11. Radon in an underground cave system in Victoria

    International Nuclear Information System (INIS)

    Hedt, J.C.; Boal, T.J.

    1998-01-01

    Radon levels in a cave system in Victoria have been measured. The variation of radon and radon progeny levels with time, position throughout the cave and season have been determined. The radiation exposure of tour guides were estimated. The data is being used to develop a radiation management plan for the tour guides. Radon concentration within a cave system was proven to be dependent to a large extent upon the rate of air exchange with outside. Cave ventilation is the single most important factor in determining if there is diurnal variation in the radon concentration

  12. Caves as observatories for atmospheric thermal tides: an example from Ascunsă Cave, Romania

    Directory of Open Access Journals (Sweden)

    Virgil Drăgușin

    2018-01-01

    Full Text Available As part of a microclimate study at Ascunsă Cave, Romania, we used Gemini Tinytag Plus 2 data loggers to record cave air temperature variability. At one of the monitoring points we recognized the presence of semidiurnal cycles on the order of a few thousands of a degree Celsius that could be produced under the influence of the semidiurnal tidal components of the Sun (S2 or the Moon (M2. Using a Gemini Tinytag Plus 2 data logger with an external probe we measured core rock temperature and showed that it does not influence the cave air temperature on such short time scales. We thus rejected the possibility that Earth tides, mostly produced by the lunar tidal influence on the Earth’s crust, would have had a semidiurnal influence on cave air temperature. Moreover, time series analysis revealed a 12.00-hour periodicity in temperature data, specific for the S2, allowing us to assign these variations to the influence of the thermo-tidal action of the Sun. Using the Ideal Gas Law and assuming a constant volume and amount of air, we calculated that a theoretical change in atmospheric pressure of around 40 Pa was needed to produce the temperature changes we observed. This agrees with published values of atmospheric pressure changes induced by the semidiurnal solar component of the thermal tides (S2(t. We thus can assign the observed temperature changes to semidiurnal atmospheric pressure changes (S2(p induced by the thermal excitation of the Sun. Our study signals the possibility that readily available data from cave monitoring studies around the world could be used in the study of atmospheric tides. Moreover, it appears that Ascunsă Cave acts as a natural meteorological filter on a short time scale, removing the direct thermal influences of the Sun (especially night and day differences and preserving only the barometric information from the surface.

  13. Hydrological characterization of cave drip waters in a porous limestone: Golgotha Cave, Western Australia

    Science.gov (United States)

    Mahmud, Kashif; Mariethoz, Gregoire; Baker, Andy; Treble, Pauline C.

    2018-02-01

    Cave drip water response to surface meteorological conditions is complex due to the heterogeneity of water movement in the karst unsaturated zone. Previous studies have focused on the monitoring of fractured rock limestones that have little or no primary porosity. In this study, we aim to further understand infiltration water hydrology in the Tamala Limestone of SW Australia, which is Quaternary aeolianite with primary porosity. We build on our previous studies of the Golgotha Cave system and utilize the existing spatial survey of 29 automated cave drip loggers and a lidar-based flow classification scheme, conducted in the two main chambers of this cave. We find that a daily sampling frequency at our cave site optimizes the capture of drip variability with the least possible sampling artifacts. With the optimum sampling frequency, most of the drip sites show persistent autocorrelation for at least a month, typically much longer, indicating ample storage of water feeding all stalactites investigated. Drip discharge histograms are highly variable, showing sometimes multimodal distributions. Histogram skewness is shown to relate to the wetter-than-average 2013 hydrological year and modality is affected by seasonality. The hydrological classification scheme with respect to mean discharge and the flow variation can distinguish between groundwater flow types in limestones with primary porosity, and the technique could be used to characterize different karst flow paths when high-frequency automated drip logger data are available. We observe little difference in the coefficient of variation (COV) between flow classification types, probably reflecting the ample storage due to the dominance of primary porosity at this cave site. Moreover, we do not find any relationship between drip variability and discharge within similar flow type. Finally, a combination of multidimensional scaling (MDS) and clustering by k means is used to classify similar drip types based on time series

  14. Hydrological characterization of cave drip waters in a porous limestone: Golgotha Cave, Western Australia

    Directory of Open Access Journals (Sweden)

    K. Mahmud

    2018-02-01

    Full Text Available Cave drip water response to surface meteorological conditions is complex due to the heterogeneity of water movement in the karst unsaturated zone. Previous studies have focused on the monitoring of fractured rock limestones that have little or no primary porosity. In this study, we aim to further understand infiltration water hydrology in the Tamala Limestone of SW Australia, which is Quaternary aeolianite with primary porosity. We build on our previous studies of the Golgotha Cave system and utilize the existing spatial survey of 29 automated cave drip loggers and a lidar-based flow classification scheme, conducted in the two main chambers of this cave. We find that a daily sampling frequency at our cave site optimizes the capture of drip variability with the least possible sampling artifacts. With the optimum sampling frequency, most of the drip sites show persistent autocorrelation for at least a month, typically much longer, indicating ample storage of water feeding all stalactites investigated. Drip discharge histograms are highly variable, showing sometimes multimodal distributions. Histogram skewness is shown to relate to the wetter-than-average 2013 hydrological year and modality is affected by seasonality. The hydrological classification scheme with respect to mean discharge and the flow variation can distinguish between groundwater flow types in limestones with primary porosity, and the technique could be used to characterize different karst flow paths when high-frequency automated drip logger data are available. We observe little difference in the coefficient of variation (COV between flow classification types, probably reflecting the ample storage due to the dominance of primary porosity at this cave site. Moreover, we do not find any relationship between drip variability and discharge within similar flow type. Finally, a combination of multidimensional scaling (MDS and clustering by k means is used to classify similar drip

  15. Hydrodynamic bearings

    CERN Document Server

    Bonneau, Dominique; Souchet, Dominique

    2014-01-01

    This Series provides the necessary elements to the development and validation of numerical prediction models for hydrodynamic bearings. This book describes the rheological models and the equations of lubrication. It also presents the numerical approaches used to solve the above equations by finite differences, finite volumes and finite elements methods.

  16. Long-time duration of gravitaty induced caves versus landslide aktivity in the Late Glacial-Holocene. Polish Flysch Carpathians case study

    Czech Academy of Sciences Publication Activity Database

    Margielewski, W.; Urban, J.; Zernitskaya, V.; Žák, Karel; Szura, C.

    2017-01-01

    Roč. 120 (2017), s. 30-32 ISSN 0944-4122. [Central European Geomorphology Conference /4./. 09.10.2017-13.10.2017, Bayreuth] Institutional support: RVO:67985831 Keywords : caves * Late Glacial-Holocene * Polish Flysch Carpathians Subject RIV: DB - Geology ; Mineralogy

  17. In-depth analyses of paleolithic pigments in cave climatic conditions

    Science.gov (United States)

    Touron, Stéphanie; Trichereau, Barbara; Syvilay, Delphine

    2017-07-01

    Painted caves are a specific environment which preservation needs multidisciplinary studies carried out within the different actors. The actions set-up must follow national and European ethics and treaties and be as less invasive as possible to preserve the integrity of the site. Studying colorants in caves should meet these expectations and take into account on-field conditions: high humidity rate, reduced access to electricity, etc. Therefore, non-invasive analyses should be preferred. However, their limits restrict the field of application and sometimes sampling and laboratory analyses must be used to answer the problematic. It is especially true when the pigment is covered by calcite. For this purpose, the Laser-Induced Breakdown Spectroscopy (LIBS) has been assessed to identify the composition with stratigraphic analyses. This study carries out in-depth profile on laboratory samples in conditions close to the ones meet in caves. Samples were prepared on a calcareous substrate using three pigments: red ochre, manganese black and carbon black and two binding media: water and saliva. All samples have been covered by calcite. Four sets of measurements have then been done using the LIBS instrument. The in-depth profiles were obtained using the Standard Normal Variate (SNV) normalization. For all the samples, the pigment layer was identified in the second or third shot, the calcite layer being quite thin. However, the results remain promising with the carbon black pigment but not really conclusive, the carbon being generally quite difficult to quantify.

  18. Radon exposure in uranium mining industry vs. exposure in tourist caves

    International Nuclear Information System (INIS)

    Quindos Poncela, L.; Fernandez Navarro, P.; Sainz Fernandez, C.; Gomez Arozamena, J.; Bordonoba Perez, M.

    2004-01-01

    There is a fairly general consensus among health physicists and radiation professionals that exposure to radon progeny is the largest and most variable contribution to the population's exposure to natural sources of radiation. However, this exposure is the subject of continuing debate concerning the validity of risk assessment and recommendations on how to act in radon-prone areas. The purpose of this contribution is to situate the radon issue in Spain in two very different settings. The first is a uranium mining industry located in Saelices el Chico (Salamanca), which is under strict control of the Spanish Nuclear Safety Council (CSN). We have measured radon concentrations in different workplaces in this mine over a five-year period. The second setting comprises four tourist caves, three of which are located in the province of Cantabria and the fourth on the Canary Island of Lanzarote. These caves are not subject to any administrative control of radiation exposure. Measured air 222 Rn concentrations were used to estimate annual effective doses due to radon inhalation in the two settings, and dose values were found to be from 2 to 10 times lower in the uranium mine than in the tourist caves. These results were analysed in the context of the new European Basic Safety Standards Directive (EU-BSS, 1996). (authors)

  19. Assessing the origin of unusual organic formations in lava caves from Canary Islands (Spain)

    Science.gov (United States)

    Miller, Ana Z.; de la Rosa, Jose M.; Garcia-Sanchez, Angela M.; Pereira, Manuel F. C.; Jurado, Valme; Fernández, Octavio; Knicker, Heike; Saiz-Jimenez, Cesareo

    2016-04-01

    -over-even in the series of n-alkanes observed for the topsoil and black deposits has been recognized as an indication of fire. The 13C NMR spectrum of the black deposits showed a mixture of alkyl and O-alkyl compounds, carboxylic compounds and polysaccharides. Stable isotope analysis of δ 13C performed on the cave black deposits, topsoil and vegetation confirmed that the source of the organic fraction of the sample is a combination of partially charred vegetation (mainly Erica) and organic compounds from the andic soil over the cave. Therefore, these black deposits are the result of an input of plant organic matter and charred vegetation into the cave from rock fractures, which may constitute an important source of energy for cave organisms. Acknowledgments: AZM and JMR acknowledge the support from the Marie Curie Fellowships within the 7th European Community Framework Programme (Grants PIEF-GA-2012-328689-DECAVE and PCIG12-GA-2012-333784-Biocharisma respectively). The authors acknowledge the Spanish Ministry of Economy and Competitiveness (project CGL2013-41674-P) and FEDER funds for financial support.

  20. Deciphering the complete mitochondrial genome and phylogeny of the extinct cave bear in the Paleolithic painted cave of Chauvet

    NARCIS (Netherlands)

    Bon, Céline; Caudy, Nicolas; De Dieuleveult, Maud; Fosse, Philippe; Philippe, Michel; Maksud, Frédéric; Beraud-Colomb, Éliane; Bouzaid, Eric; Kefi, Rym; Laugier, Christelle; Rousseau, Bernard; Casane, Didier; Van Der Plicht, Johannes; Elalouf, Jean-Marc

    2008-01-01

    Retrieving a large amount of genetic information from extinct species was demonstrated feasible, but complete mitochondrial genome sequences have only been deciphered for the moa, a bird that became extinct a few hundred years ago, and for Pleistocene species, such as the woolly mammoth and the

  1. Analysis of the main factors affecting the evaluation of the dose in workplaces: the case of tourist caves

    International Nuclear Information System (INIS)

    Sainz, C.; Santiago Quindos, L.; Fuente, I.; Nicolas, J.; Quindos, L.

    2006-01-01

    Since 2001, Spanish law incorporated EURATOM basic standards for radiological protection, which include a request at the European Communities Member States to determine the working places on which exposure to natural radiation is significant. On Title VII (BOE 178/2001) radiation coming from natural sources has analogous role than radiation emitted from artificial ones used to. High concentrations of radon exist in several workplaces like tourist caves mainly because of the low ventilation rates existing at these enclosures. In this sense, in its 1990 publication, the ICRP recommended that high exposures of radon in workplace could be regarded as the responsibility of the operating management and should be considered as occupational exposure. In developed caves in which guides provide tours for the general public great care is needed for taking remedial actions concerning radon, because in some circumstances forced ventilation may alter the humidity inside the cave affecting the some of the formations or paintings that attract tourists. Tourist guides can work about 1900 hours per year, so the only option to protect them and other cave workers from radon exposure is to apply an appropriate system of radiation protection mainly based on limitation of exposure by restricting the amount of time spent in the cave. The information needed for carrying out the above mentioned protecting actions is related with the specific characteristics of the cave concerning the behaviour of radon and it decay products. In order to perform a precise effective dose calculation, factors like unattached progeny fraction (fp), equilibrium factor (F) and particle concentration (Z) are of main importance. One of the specific characteristic of the caves is the high unattached fraction due to very low particle concentration. The fp values can be higher than 0.1, for places with low ventilation and without additional aerosol sources, with Z -3 .In this work the results of the first stage of

  2. Analysis of the main factors affecting the evaluation of the dose in workplaces: the case of tourist caves

    Energy Technology Data Exchange (ETDEWEB)

    Sainz, C.; Santiago Quindos, L.; Fuente, I.; Nicolas, J.; Quindos, L. [Cantabria Univ., Dept. of Medical Physics. RADON Group, Faculty of Medicine, (Spain)

    2006-07-01

    Since 2001, Spanish law incorporated EURATOM basic standards for radiological protection, which include a request at the European Communities Member States to determine the working places on which exposure to natural radiation is significant. On Title VII (BOE 178/2001) radiation coming from natural sources has analogous role than radiation emitted from artificial ones used to. High concentrations of radon exist in several workplaces like tourist caves mainly because of the low ventilation rates existing at these enclosures. In this sense, in its 1990 publication, the ICRP recommended that high exposures of radon in workplace could be regarded as the responsibility of the operating management and should be considered as occupational exposure. In developed caves in which guides provide tours for the general public great care is needed for taking remedial actions concerning radon, because in some circumstances forced ventilation may alter the humidity inside the cave affecting the some of the formations or paintings that attract tourists. Tourist guides can work about 1900 hours per year, so the only option to protect them and other cave workers from radon exposure is to apply an appropriate system of radiation protection mainly based on limitation of exposure by restricting the amount of time spent in the cave. The information needed for carrying out the above mentioned protecting actions is related with the specific characteristics of the cave concerning the behaviour of radon and it decay products. In order to perform a precise effective dose calculation, factors like unattached progeny fraction (fp), equilibrium factor (F) and particle concentration (Z) are of main importance. One of the specific characteristic of the caves is the high unattached fraction due to very low particle concentration. The fp values can be higher than 0.1, for places with low ventilation and without additional aerosol sources, with Z < 4 103 particle cm{sup -3}.In this work the results

  3. The archaeal diversity in a cave system and its implications for life on other planets

    Science.gov (United States)

    Leuko, Stefan; Rettberg, Petra; De Waele, Jo; Bessone, Loredana; Sauro, Francesco; Sanna, Laura

    The quest of exploring and looking for life in new places is a human desire since centuries. Nowadays, we are not only looking on planet Earth any more, but our endeavours focus on nearby planets in our solar system. At this point in time, we are not able to send manned missions to other planets, but to be ready and prepared for the day, training today is pivotal. Developed by the European Space Agency (ESA) since 2008, these CAVES missions (Cooperative Adventure for Valuing and Exercising human behaviour and performance Skills), prepare astronauts to work safely and effectively and solve problems as a multicultural team while exploring uncharted underground natural areas (i.e. caves) using space procedures. The hypogean environment is also of great interest for astrobiological research as cave conditions may resemble those in extra-terrestrial environments. Besides the main focus of exploration and skill training, future astronauts are also trained in taking microbiological samples for analysis during the exploration and for further analysis in the lab. During the 2013 mission, astronauts collected soil samples and employed flocked swaps to sample areas with little or no visible soil. Microscopic analysis back in the lab revealed a diverse spectrum of different cell shapes and sizes. Samples were further analysed employing molecular tools such as RFLP analysis, 16s rRNA clone libraries and sequence analysis. RFLP pattern analysis revealed that the community can be divided in 9 main groups and several single patterns. The largest group (40% of all analysed clones) belong to the clade of ammonia oxidizing archaea Nitrosopumilus spp.. Dividing the results by sampling point, it showed that the highest diversity of organisms was located on the flocked swaps, which is interesting as the sample was taken from a rock surface with no visible organic matter. By analysis low energy systems like a cave, we may be able to find clues for what could be necessary to survive on a

  4. A geochronological approach for cave evolution in the Cantabrian Coast (Pindal Cave, NW Spain)

    Science.gov (United States)

    Jimenez-Sanchez, M.; Bischoff, J.L.; Stoll, H.; Aranburu, A.

    2006-01-01

    Some of the oldest speleothems in the North Cantabrian Coast (Spain) are reported for the first time in this work. Pindal Cave is developed at 24 m above sea level, in a karstic massif reaching its highest surface in a marine terrace (rasa) located at 50-64 m above the present sea level. Several phases of evolution were previously recognized into the cave, including block collapse of the roof, episodic flooding and detrital sedimentation, and chemical precipitation of at least four speleothem generations over both alluvial and collapse deposits. Three of these speleothem generations have been dated by U/Th. The first generation yielded ages from 124,2 ?? 1, 5 ka BP to 73,1 ?? 0,9 ka BP, giving a minimum age for the main detritic sediments in the cave. The second one is not dated. The third generation gives an age of 3,71 ?? 0,4 ka BP (mathematically corrected to 2.7 ?? 0.5 ka BP), while for the youngest generation, with actively growing stalagmites in the cave, basal ages of 200 years BP are estimated by counting annual laminae. The data suggest a tentative maximum elevation rate close to 0, 2 mm/yr for the Cantabrian Margin in this area, although further chronological studies will be needed to check this hypothesis. ?? 2006 Gebru??der Borntraeger.

  5. World Register of marine Cave Species (WoRCS: a new Thematic Species Database for marine and anchialine cave biodiversity

    Directory of Open Access Journals (Sweden)

    Vasilis Gerovasileiou

    2016-09-01

    Full Text Available Scientific exploration of marine cave environments and anchialine ecosystems over recent decades has led to outstanding discoveries of novel taxa, increasing our knowledge of biodiversity. However, biological research on underwater caves has taken place only in a few areas of the world and relevant information remains fragmented in isolated publications and databases. This fragmentation makes assessing the conservation status of marine cave species especially problematic, and this issue should be addressed urgently given the stresses resulting from planned and rampant development in the coastal zone worldwide. The goal of the World Register of marine Cave Species (WoRCS initiative is to create a comprehensive taxonomic and ecological database of known species from marine caves and anchialine systems worldwide and to present this as a Thematic Species Database (TSD of the World Register of marine Species (WoRMS. WoRCS will incorporate ecological data (e.g., type of environment, salinity regimes, and cave zone as well as geographical information on the distribution of species in cave and anchialine environments. Biodiversity data will be progressively assembled from individual database sources at regional, national or local levels, as well as from literature sources (estimate: >20,000 existing records of cave-dwelling species scattered in several databases. Information will be organized in the WoRCS database following a standard glossary based on existing terminology. Cave-related information will be managed by the WoRCS thematic editors with all data dynamically linked to WoRMS and its team of taxonomic editors. In order to mobilize data into global biogeographic databases, a Gazetteer of the Marine and Anchialine Caves of the World will be established. The presence records of species could be eventually georeferenced for submission to the Ocean Biogeographic Information System (OBIS and constitute an important dataset for biogeographical and

  6. Bearing structures

    International Nuclear Information System (INIS)

    Lee, A.S.; Preece, G.E.

    1988-01-01

    A hydrostatic bearing for the lower end of the vertical shaft of a sodium pump comprises a support shell encircling the shaft and a bush located between the shell and shaft. Liquid sodium is fed from the pump outlet to the bush/shaft and bush/shell interfaces to provide hydrostatic support. The bush outer surface and the shell inner surface are of complementary part-spherical shape and the bush floats relative to the shaft so that the bush can align itself with the shaft axis. Monitoring of the relative rotational speed of the bush with respect to the shaft (such rotation being induced by the viscous drag forces present) is also performed for the purposes of detecting abnormal operation of the bearing or partial seizure, at least one magnet is rotatable with the bush, and a magnetic sensor provides an output having a frequency related to the speed of the bush. (author)

  7. Radon Exposures in the Caves of Tenerife (Canary Islands)

    International Nuclear Information System (INIS)

    Pinza-Molina, C.; Alcaide, J.M.; Rodriques-Bethencourt, R.; Hernandez-Armas, J.

    1999-01-01

    There are more than a hundred volcanic caves and pits of various lengths on the island of Tenerife (Canary Islands, Spain). The results are presented of atmospheric radon measurements performed in three of these caves and in three pits. One of the caves selected, El Viento Cave, is nearly 20 km in length and is the longest volcanic tube in the Canarian archipelago and the second longest in the world. The measurements were performed over two distinct periods during the year using passive polycarbonate detectors. The mean radon concentrations range between 0.3 and 8 kBq.m -3 , the maximum value corresponds to a site located at 1850 m from the mouth of El Viento Cave. Possible touristic development of these caves has been taken into account in estimating the effective doses for visitors and guides (considered separately). The values obtained range from 0.3 to 100 μSv per visit for visitors. The largest effective dose would correspond to that for guides at 41 mSv.y -1 in the Viento Cave. This result would make protection against radiological hazards obligatory if the cave were to be developed as a site for tourism. (author)

  8. Measurements of radon concentrations at caves in Jeju

    Energy Technology Data Exchange (ETDEWEB)

    Go, S. H.; Kang, D. H.; Jung, B. J. [Cheju National University, Cheju (Korea, Republic of)

    2004-07-01

    Radon is a radioactive gas emitting {alpha} particles. It is chemically stable due to its inert characteristic. While its daughter products, {sup 218}Po, {sup 214}Bi, {sup 214}Pb and {sup 214}Po, attached with aerosol particles, is known to cause lung cancer. As radon is produced from uranium and thorium, it accumulates in poorly ventilative underground voids such as caves and mine. Radon concentrations at caves in Jeju were measured in this study. The measurements were made by setting three CR-39 detectors for 70 days at 2 {approx} 4 positions in Manjang, Hyupjae and Ssangyong caves. The radon levels of the caves spread 403.1 . 606.7 Bq/m{sup 3}. With these results, it is concluded that the Jeju caves have 6 times higher radon concentrations than ordinary house of 65.3 Bq/m{sup 3} and that they are higher than Seoul subway stations due to poor ventilation. While, the caves in Jeju have lower radon concentrations than limestone caves of Robin Hood. The radon concentration in the middle of Manjang cave is slightly higher than the action level in the work place of 500 Bq/m{sup 3} suggested by the ICRP. The measurement errors are estimated to be less than 5 % from its calibration factor.

  9. Measurements of radon concentrations at caves in Jeju

    International Nuclear Information System (INIS)

    Go, S. H.; Kang, D. H.; Jung, B. J.

    2004-01-01

    Radon is a radioactive gas emitting α particles. It is chemically stable due to its inert characteristic. While its daughter products, 218 Po, 214 Bi, 214 Pb and 214 Po, attached with aerosol particles, is known to cause lung cancer. As radon is produced from uranium and thorium, it accumulates in poorly ventilative underground voids such as caves and mine. Radon concentrations at caves in Jeju were measured in this study. The measurements were made by setting three CR-39 detectors for 70 days at 2 ∼ 4 positions in Manjang, Hyupjae and Ssangyong caves. The radon levels of the caves spread 403.1 . 606.7 Bq/m 3 . With these results, it is concluded that the Jeju caves have 6 times higher radon concentrations than ordinary house of 65.3 Bq/m 3 and that they are higher than Seoul subway stations due to poor ventilation. While, the caves in Jeju have lower radon concentrations than limestone caves of Robin Hood. The radon concentration in the middle of Manjang cave is slightly higher than the action level in the work place of 500 Bq/m 3 suggested by the ICRP. The measurement errors are estimated to be less than 5 % from its calibration factor

  10. Journal Bearings

    Directory of Open Access Journals (Sweden)

    Renato Brancati

    1999-01-01

    determined after acquiring and analysing the orbits described by the journal axis for assigned unbalance values in different operating conditions. Analysis of the results shows some particular operating features that were not entirely predicted by the theoretical model and which may give rise to malfunctions in the rotor-tilting pad bearings system. The tests were carried out in the rotor dynamics laboratory of the Dipartimento di Ingegneria Meccanica per l'Energetica at the University of Naples.

  11. Camshaft bearing arrangement

    Energy Technology Data Exchange (ETDEWEB)

    Aoi, K.; Ozawa, T.

    1986-06-10

    A bearing arrangement is described for the camshaft of an internal combustion engine or the like which camshaft is formed along its length in axial order with a first bearing surface, a first cam lobe, a second bearing surface, a second cam lobe, a third bearing surface, a third cam lobe and a fourth bearing surface, the improvement comprising first bearing means extending around substantially the full circumference of the first bearing surface and journaling the first bearing surface, second bearing means extending around substantially less than the circumference of the second bearing surface and journaling the second bearing surface, third bearing means extending around substantially less than the circumference of the third bearing surface and journaling the third bearing surface, and fourth bearing means extending around substantially the full circumference of the fourth bearing surface and journaling the first bearing surface.

  12. Petrographic and geochemical study on cave pearls from Kanaan Cave (Lebanon

    Directory of Open Access Journals (Sweden)

    Nader Fadi H.

    2007-01-01

    Full Text Available The Kanaan cave is situated at the coastal zone, north of Beirut City (capital of Lebanon. The cave is located within the upper part of the Jurassic Kesrouane Formation (Liassic to Oxfordian which consists mainly of micritic limestone. Twenty seven cave pearls were subjected to petrographic (conventional and scanning electron microscopy and geochemical analyses (major/trace elements and stable isotopes. The cave pearls were found in an agitated splash-pool with low mud content. They are believed to have formed through chemical precipitation of calcite in water over-saturated with calcium. The nucleus and micritic laminae show δ18OV-PDB values of about -5.0‰ and δ13C V-PDB values of -11.8‰, while the surrounding calcite spar laminae resulted in δ18OV-PDB ranging between -5.3 and -5.2‰, and δ13C V-PDB between -12.3 and -12.1‰. A genesis/diagenesis model for these speleothems is proposed involving recrystallization which has selectively affected the inner layers of the cave pearls. This is chiefly invoked by sparry calcite crystals ‘invading’ the inner micrite cortical laminae and the nuclei (cross-cutting the pre-existing mud-envelopes, and the slight depletion in δ18O values from inner to outer cortical layers. The calculated δ18OV-SMOW of the water (-4.2‰ matches with data on meteoric water signature for the central eastern Mediterranean region.

  13. Urang Cave Karst Environmental Development, as Tourism Object

    Directory of Open Access Journals (Sweden)

    Srijono Srijono

    2013-12-01

    Full Text Available Karst environment become an alternative tourist destination as well as to boost local revenues. In karst environments in Grobogan District, Central Java Province, formed Urang Cave, with an interesting endokarst phenomenon. This study aims to do zoning district Urang Cave as tourist sites. The research method is using contour maps as a base map of Urang Cave karst environment geomorphological mapping. Geomorphological data processing is using ArcView GIS 3.3 program. Land use map refers to RBI, scale 1:25.000. Geomorphological analysis refers to the Ministry of Energy and Mineral Resources No. 1456.K/20/MEM/2000, and petrography. Each development zone is analyzed its geophysical environmental element, then set scoring and value summation. For comprehensive environmental element analysis, chemical analysis of rocks, and water-soil chemistry. In reference to Minister of Energy Mineral Resource decrees No. 1456/K/20/MEM/2000, Urang Cave zoning defined into 3 (three zone, as follow: the Protected Zone, Cultivation Zone 1, and Cultivation Zone 2. Protected Zone, consists of Urang Cave tunnel/hallway with a unique spheleothem in it. This zone as a cave tracking site tourism, potential to produce karst water as a decent drinking water while maintaining hardness. Cultivation Zone 1 is spreading about 200 m in distance from outer appearance of spring around the cave hallway. In this zone mining of cave sediments may be done in the inactive form caves, without changing the state of the existing major exokarst morphology. Cultivation Zone 2, an outer zone, located farthest from the tunnel/hallway Urang Cave. Utilization of this zone as a limestone mining quarry, although only on a small scale.

  14. A cave response to environmental changes in the Late Pleistocene: a study of Budimirica Cave sediments, Macedonia

    Czech Academy of Sciences Publication Activity Database

    Temovski, M.; Pruner, Petr; Hercman, H.; Bosák, Pavel

    2016-01-01

    Roč. 69, č. 3 (2016), s. 307-316 ISSN 1330-030X Institutional support: RVO:67985831 Keywords : cave sediments * palaeoenvironmental changes * Late Pleistocene * Budimirica Cave * Macedonia Subject RIV: DB - Geology ; Mineralogy Impact factor: 0.595, year: 2016 http://www. geologia -croatica.hr/ojs/index.php/GC

  15. World Register of marine Cave Species (WoRCS): a new Thematic Species Database for marine and anchialine cave biodiversity

    NARCIS (Netherlands)

    Gerovasileiou, Vasilis; Martínez, Alejandro; Álvarez, Fernando; Boxshall, Geoff; Humphreys, William F.; Jaume, Damià; Becking, L.E.; Muricy, Guilherme; Hengstum, van Peter J.; Dekeyzer, Stefanie; Decock, Wim; Vanhoorne, Bart; Vandepitte, Leen; Bailly, Nicolas; Iliffe, Thomas M.

    2016-01-01

    Scientific exploration of marine cave environments and anchialine ecosystems over recent decades has led to outstanding discoveries of novel taxa, increasing our knowledge of biodiversity. However, biological research on underwater caves has taken place only in a few areas of the world and relevant

  16. Fossil human remains from Bolomor Cave (Valencia, Spain).

    Science.gov (United States)

    Arsuaga, Juan Luis; Fernández Peris, Josep; Gracia-Téllez, Ana; Quam, Rolf; Carretero, José Miguel; Barciela González, Virginia; Blasco, Ruth; Cuartero, Felipe; Sañudo, Pablo

    2012-05-01

    Systematic excavations carried out since 1989 at Bolomor Cave have led to the recovery of four Pleistocene human fossil remains, consisting of a fibular fragment, two isolated teeth, and a nearly complete adult parietal bone. All of these specimens date to the late Middle and early Late Pleistocene (MIS 7-5e). The fibular fragment shows thick cortical bone, an archaic feature found in non-modern (i.e. non-Homo sapiens) members of the genus Homo. Among the dental remains, the lack of a midtrigonid crest in the M(1) represents a departure from the morphology reported for the majority of Neandertal specimens, while the large dimensions and pronounced shoveling of the marginal ridges in the C(1) are similar to other European Middle and late Pleistocene fossils. The parietal bone is very thick, with dimensions that generally fall above Neandertal fossils and resemble more closely the Middle Pleistocene Atapuerca (SH) adult specimens. Based on the presence of archaic features, all the fossils from Bolomor are attributed to the Neandertal evolutionary lineage. Copyright © 2012 Elsevier Ltd. All rights reserved.

  17. Seven Possible Cave Skylights on Mars

    Science.gov (United States)

    2007-01-01

    [figure removed for brevity, see original site] Figure 1 Seven very dark holes on the north slope of a Martian volcano have been proposed as possible cave skylights, based on day-night temperature patterns suggesting they are openings to subsurface spaces. These six excerpts of images taken in visible-wavelength light by the Thermal Emission Imaging System camera on NASA's Mars Odyssey orbiter show the seven openings. Solar illumination comes from the left in each frame. The volcano is Arsia Mons, at 9 degrees south latitude, 239 degrees east longitude. The features have been given informal names to aid comparative discussion (see figure 1). They range in diameter from about 100 meters (328 feet) to about 225 meters (738 feet). The candidate cave skylights are (A) 'Dena,' (B) 'Chloe,' (C) 'Wendy,' (D) 'Annie,' (E) 'Abby' (left) and 'Nikki,' and (F) 'Jeanne.' Arrows signify north and the direction of illumination. Mars Odyssey is managed by NASA's Jet Propulsion Laboratory, a division of the California Institute of Technology, Pasadena, for NASA's Science Mission Directorate, Washington. Lockheed Martin Space Systems, Denver, is the prime contractor for the project and built the spacecraft. The orbiter's Thermal Emission Imaging System was developed by Arizona State University, Tempe, in collaboration with Raytheon Santa Barbara Remote Sensing, Santa Barbara, Calif., and is operated by Arizona State University.

  18. Eogenetic caves in conglomerate: an example from Udin Boršt, Slovenia

    Directory of Open Access Journals (Sweden)

    Lipar Matej

    2011-01-01

    Full Text Available Udin Boršt is a karstified terrace of carbonate rock, which is of fluvioglacial origin, and is situated in the north-western part of Slovenia. There are 15 registered caves, which have been interpreted as caves in conglomerate, while karst of Udin Boršt itself was interpreted as conglomerate karst, shallow karst or isolated karst. In this article, caves in Udin Boršt have been interpreted as eogenetic caves. Based on porosity and bedding material, different types of caves and cave passages have developed. Four general types of eogenetic caves found in Udin Boršt are; linear stream caves, shelter caves, breakdown caves and vadose shafts.

  19. Management in a neotropical show cave: planning for invertebrates conservation

    Directory of Open Access Journals (Sweden)

    Thais Giovannini Pellegrini

    2012-07-01

    Full Text Available Lapa Nova is a dolomitic cave about 4.5 km long located in northwestern Minas Gerais state, Brazil. The cave experiences intense tourism, concentrated over a single period of the year, during the Feast of Our Lady of Lapa. In order to evaluate the impacts felt by the invertebrate community from this tourism, a new methodology was proposed. Four types of areas (intense visitation area, outlying visitation areas, moderate visitation areas and no-visitation areas were sampled for invertebrates. There was one sampling prior and another on the last day of the 128th feast, to evaluate the effects of visitation on cave-dwelling invertebrates. Results show that invertebrate populations residing in more intensely visited areas of the cave undergo changes in distribution following the event. As a consequence of tourism, invertebrates shift to outlying locations from the visited area, which serve as refuges to the communities. Apparently, the fact that there are places inside Lapa Nova inaccessible to tourists reduces the impact suffered by the invertebrate community, as those sites serve as refuges for cave-dwelling organisms during the pilgrimage. A proper management plan was devised for the tourism/religious use of the cave. It consists basically of delimiting marked pathways for tourists, allowing invertebrates to seek shelter at locations outside visited areas and keeping no-visitation areas off-limits to tourism based on the results of the visitation effects on cave-dwelling invertebrates.

  20. Radon in the Creswell Crags Permian limestone caves

    International Nuclear Information System (INIS)

    Gillmore, G.K.; Phillips, P.S.; Denman, A.R.; Gilbertson, D.D.

    2002-01-01

    An investigation of radon levels in the caves of Creswell Crags, Derbyshire, an important Site of Special Scientific Interest (SSSI) shows that the Lower Magnesian Limestone (Permian) caves have moderate to raised radon gas levels (27-7800 Bq m -3 ) which generally increase with increasing distance into the caves from the entrance regions. This feature is partly explained in terms of cave ventilation and topography. While these levels are generally below the Action Level in the workplace (400 Bq m -3 in the UK), they are above the Action Level for domestic properties (200 Bq m -3 ). Creswell Crags has approximately 40,000 visitors per year and therefore a quantification of effective dose is important for both visitors and guides to the Robin Hood show cave. Due to short exposure times the dose received by visitors is low (0.0016 mSv/visit) and regulations concerning exposure are not contravened. Similarly, the dose received by guides is fairly low (0.4 mSv/annum) due in part to current working practice. However, the risk to researchers entering the more inaccessible areas of the cave system is higher (0.06 mSv/visit). This survey also investigated the effect of seasonal variations on recorded radon concentration. From this work summer to winter ratios of between 1.1 and 9.51 were determined for different locations within the largest cave system

  1. Radon concentration measurements in the desert caves of Saudi Arabia

    International Nuclear Information System (INIS)

    Al-Mustafa, Hanan; Al-Jarallah, M.I.; Fazal-ur-Rehman; Abu-Jarad, F.

    2005-01-01

    Beneath the harsh deserts of Saudi Arabia lie dark chambers and complex mazes filled with strange shapes and wondrous beauty. Radon concentration measurements have been carried out in the desert caves of Al-Somman Plateau in the Eastern Province of Saudi Arabia. Passive radon dosimeters, based on alpha particle etch track detectors with an inlet filter, were used in this study. A total of 59 dosimeters were placed in five caves for a period of six months. Out of 59 dosimeters, 37 could be collected for analysis. Measurements showed significant variations in radon concentrations in caves depending upon their natural ventilation. The results of the study show that the average radon concentration in the different caves ranges from 74 up to 451Bqm -3 . The average radon concentration in four of the caves was low in the range 74-114Bqm -3 . However, one cave showed an average radon concentration of 451Bqm -3 . Radon is not a problem for tourists in the majority of caves. However, sometimes it may imply some limitation to the working time of guides

  2. Radon concentration measurements in the desert caves of Saudi Arabia

    Energy Technology Data Exchange (ETDEWEB)

    Al-Mustafa, Hanan [Women College, P. O. Box 838, Dammam 31113 (Saudi Arabia); Al-Jarallah, M.I. [Department of Physics, King Fahd University of Petroleum and Minerals, Dhahran 31261 (Saudi Arabia)]. E-mail: mibrahim@kfupm.edu.sa; Fazal-ur-Rehman [Department of Physics, King Fahd University of Petroleum and Minerals, Dhahran 31261 (Saudi Arabia); Abu-Jarad, F. [Radiation Protection Unit, Environmental Protection Department, Saudi Aramco P.O. Box 13027, Dhahran 31311 (Saudi Arabia)

    2005-11-15

    Beneath the harsh deserts of Saudi Arabia lie dark chambers and complex mazes filled with strange shapes and wondrous beauty. Radon concentration measurements have been carried out in the desert caves of Al-Somman Plateau in the Eastern Province of Saudi Arabia. Passive radon dosimeters, based on alpha particle etch track detectors with an inlet filter, were used in this study. A total of 59 dosimeters were placed in five caves for a period of six months. Out of 59 dosimeters, 37 could be collected for analysis. Measurements showed significant variations in radon concentrations in caves depending upon their natural ventilation. The results of the study show that the average radon concentration in the different caves ranges from 74 up to 451Bqm{sup -3}. The average radon concentration in four of the caves was low in the range 74-114Bqm{sup -3}. However, one cave showed an average radon concentration of 451Bqm{sup -3}. Radon is not a problem for tourists in the majority of caves. However, sometimes it may imply some limitation to the working time of guides.

  3. ComputerApplications and Virtual Environments (CAVE)

    Science.gov (United States)

    1993-01-01

    Virtual Reality (VR) can provide cost effective methods to design and evaluate components and systems for maintenance and refurbishment operations. The Marshall Space Flight Centerr (MSFC) in Huntsville, Alabama began to utilize VR for design analysis in the X-34 experimental reusable space vehicle. Analysts at MSFC's Computer Applications and Virtual Environments (CAVE) used Head Mounted Displays (HMD) (pictured), spatial trackers and gesture inputs as a means to animate or inhabit a properly sized virtual human model. These models were used in a VR scenario as a way to determine functionality of space and maintenance requirements for the virtual X-34. The primary functions of the virtual X-34 mockup was to support operations development and design analysis for engine removal, the engine compartment and the aft fuselage. This capability provided general visualization support to engineers and designers at MSFC and to the System Design Freeze Review at Orbital Sciences Corporation (OSC). The X-34 program was cancelled in 2001.

  4. Pathologies in the extinct Pleistocene Eurasian steppe lion Panthera leo spelaea ()-Results of fights with hyenas, bears and lions and other ecological stresses.

    Science.gov (United States)

    Rothschild, Bruce M; Diedrich, Cajus G

    2012-12-01

    Late Pleistocene Eurasian steppe lions Panthera leo spelaea (Goldfuss, 1810) frequently (3 of 13) have skull damage attributable to bites. Such evidence is found only in lions from hyena or cave bear dens. Wounds on frontal and parietal bones appear to be the result of battles during cave bear hunts, by antagonistic conflicts with hyenas, and less often from fights with conspecifics. Skull bite damage is extremely rare in modern lions, suggesting that this Eurasian lion pathology is the result of inter-specific (with cave bears) rather than intra-specific conflicts. The sex specificity of maxillary porosity (found only in lions among modern felidae) is also documented in its close genetic relation, P. l. spelaea. The pattern of skeletal exostotic reaction reveals them to have been pursuit rather than ambush predators. Copyright © 2012 Elsevier Inc. All rights reserved.

  5. Roof instability characteristics and pre-grouting of the roof caving zone in residual coal mining

    Science.gov (United States)

    Zhao, Tong; Liu, Changyou

    2017-12-01

    Abandoned roadways and roof caving zones are commonly found in residual coal, and can destroy the integrity of the coal seam and roof. Resulting from mining-induced stress, continuous collapse and fracture instability in roof caving zones (RCZs) jeopardize the safety and efficiency of residual coal mining. Based on the engineering geology conditions of remining face 3101 in Shenghua Mine, the roof fracture and instability features of the RCZ were analyzed through physical simulation, theoretical analysis, and field measurements. In this case, influenced by the RCZ, the main roof across the RCZ fractured and rotated towards the goaf, greatly increasing the working resistance, and crushing the supports. The sudden instability of the coal pillars weakened its support of the main roof, thus resulting in long-key blocks across the RCZ and hinged roof structures, which significantly decreased the stability of the underlying immediate roof. This study establishes a mechanical model for the interactions between the surrounding rock and the supports in the RCZ, determines the reasonable working resistance, and examines the use of pre-grouting solidification restoration technology (PSRT) to solidify the RCZ and reinforce the coal pillars—thus increasing their bearing capacity. Field measurements revealed no roof flaking, inhomogeneous loading or support crushing, indicating that the PSRT effectively controlled the surrounding rock of the RCZ.

  6. First assessment on the air CO2 dynamic in the show caves of tropical karst, Vietnam

    Directory of Open Access Journals (Sweden)

    Duc A. Trinh

    2018-01-01

    Full Text Available In this study, air, water, and host rock in show caves in a Vietnam’s karst region was monitored and analyzed to identify the ventilation regime and track the cave air CO2 sources. In general, the studied caves are well ventilated. In dynamic – multiple entrance caves, air ventilation is described with the use of U shape model. In static – single entrance cave, air circulation is explained by cold air trap model. Both ventilation models suggest that air is more circulated in winter than in summer. Seasonally, the cave air CO2 increases from early spring to summer. Value in the deepest part of the single-entrance cave is approximately 1,000 ppmv and 8,000 ppmv in early spring and summer, respectively. In multiple-entrance and wet caves, CO2 level is fairly constant all over the show section, increasing from 500 ppmv in early spring to 2,000 ppmv in summer. Data of microclimate, CO2 content, and particularly δ13C show that cave air, particularly in single entrance cave, has higher CO2 concentration during summer due to a stagnation of cave air circulation and an elevated CO2 input from soil and epikarst. The cave air CO2 increase is also observed after intense rainfalls. A factor that increase cave air CO2 in show caves during the festive days could probably be huma n exhaling but the extent of human factor in these studied cave systems should be further investigated. Cave waters including cave pools and streams mediate CO2 level in wet caves. Above all, the atmospheric fraction of CO2 is always dominant (>60% in all cave sections.

  7. Organochlorine residues in bat guano from nine Mexican caves, 1991

    Science.gov (United States)

    Clark, D.R.; Moreno-Valdez, A.; Mora, M.A.

    1995-01-01

    Samples of bat guano, primarily from Mexican free-tailed bats (Tadarida brasiliensis), were collected at nine bat roosts in caves in northern and eastern Mexico and analysed for organochlorine residues. DDE, the most abundant residue found in each cave, was highest (0.99 p.p.m. dry weight) at Ojuela Cave, Durango. Other studies of DDE in bat guano indicate that this concentration is too low to reflect harmful concentrations in the bats themselves. The DDE at Ojuela may represent either lingering residues from use of DDT years ago in the Ojuela area of perhaps depuration loss from migrant bats with summer maternity roost(s) in a DDE-contaminated area such as Carlsbad Cavern, New Mexico. Presence of o,p-DDT at Tio Bartolo Cave, Nuevo Leon, indicates recent use of DDT, but the concentration of this contaminant was low. Possible impacts on bat colonies of the organophosphorus and carbamate insecticides now in extensive use are unknown.

  8. Urban landscape and architectural workshop Škocjan Caves 2007

    Directory of Open Access Journals (Sweden)

    Andrej Mahovič

    2012-01-01

    Full Text Available The fundamental aim and purpose of the Škocjan Caves 2007 student workshop was for students participating in the seminar of the Faculty of Architecture in Ljubljana to recognise and address some specific spatial and design issues for the further sustainable development of the Škocjan Caves. The working hypothesis of the workshop was that, in spite of significant results in the protection and development of the Caves which have been achieved in the past ten years, it is still necessary to address some spatial issues through an academic process, and to offer different architectural and spatial solutions. The aforesaid is even more important as the Caves are recognised as the only natural and cultural heritage of the Republic of Slovenia to be listed as a UNESCO World Heritage site since 1986.

  9. Center for Advanced Energy Studies: Computer Assisted Virtual Environment (CAVE)

    Data.gov (United States)

    Federal Laboratory Consortium — The laboratory contains a four-walled 3D computer assisted virtual environment - or CAVE TM — that allows scientists and engineers to literally walk into their data...

  10. Luminescence dating at Rose cottage cave: a progress report

    CSIR Research Space (South Africa)

    Woodborne, S

    1997-10-01

    Full Text Available Deal with infrared-stimulated luminescence and thermoluminescence dates from Rose Cottage Cave in South Africa. Discrepancy between luminescence and radiocarbon dates; Concentration of radioactive elements in sediments before and after leaching...

  11. Ancient photosynthetic eukaryote biofilms in an Atacama Desert coastal cave

    Science.gov (United States)

    Azua-Bustos, A.; Gonzalez-Silva, C.; Mancilla, R.A.; Salas, L.; Palma, R.E.; Wynne, J.J.; McKay, C.P.; Vicuna, R.

    2009-01-01

    Caves offer a stable and protected environment from harsh and changing outside prevailing conditions. Hence, they represent an interesting habitat for studying life in extreme environments. Here, we report the presence of a member of the ancient eukaryote red algae Cyanidium group in a coastal cave of the hyperarid Atacama Desert. This microorganism was found to form a seemingly monospecific biofilm growing under extremely low photon flux levels. Our work suggests that this species, Cyanidium sp. Atacama, is a new member of a recently proposed novel monophyletic lineage of mesophilic "cave" Cyanidium sp., distinct from the remaining three other lineages which are all thermo-acidophilic. The cave described in this work may represent an evolutionary island for life in the midst of the Atacama Desert. ?? Springer Science + Business Media, LLC 2009.

  12. Simultaneous caving and surface restoration system for oil shale mining

    Energy Technology Data Exchange (ETDEWEB)

    Allsman, P.T.

    1968-10-01

    A modified caving method is introduced for mining oil shale and simultaneous restoration of the land surface by return of spent shale onto the subsided area. Other methods have been designed to mine the relatively thin richer beds occurring near outcrops in the Piceance Creek Basin of NW. Colorado. Since the discovery of the much thicker beds in the N.-central part of the basin, some attention has focused on in situ and open-pit methods of recovery. Although caving has been recognized as a possible means of mining shale, most people have been skeptical of its success. This stems from the unknown and salient factors of cavability and size of broken rock with caving. Wisdom would seem to dictate that serious evaluation of the caving method be made along with the other methods.

  13. Minerals cave, Volcan Irazu, Costa Rica: description, mineralogy and origin

    International Nuclear Information System (INIS)

    Ulloa, Andres; Campos-Fernandez, Cristian S.; Rojas, Leonardo

    2013-01-01

    Two caves are found in the NW sector of the main crater of the Volcan Irazu at the base of the crown of a glide. The caves are located in an area of structural weakness of the massif developed in sequences of pyroclasts with hydrothermal alteration. Several explorations are organized for the recognition of the caves. The purpose has been of collecting samples and photographs for mineralogical and topographic analyses, through X-ray diffractometry. The minerals present in the samples are compared and identified by means of PDF-2 power x-ray diffraction database of the 2007 ICDD, International Center for Diffraction Data. The origin of the caves has been studied, and it is suggested to carry out other of complement studies [es

  14. The biogeochemistry of anchialine caves: Progress and possibilities

    Science.gov (United States)

    Pohlman, John W.

    2011-01-01

    Recent investigations of anchialine caves and sinkholes have identified complex food webs dependent on detrital and, in some cases, chemosynthetically produced organic matter. Chemosynthetic microbes in anchialine systems obtain energy from reduced compounds produced during organic matter degradation (e.g., sulfide, ammonium, and methane), similar to what occurs in deep ocean cold seeps and mud volcanoes, but distinct from dominant processes operating at hydrothermal vents and sulfurous mineral caves where the primary energy source is mantle derived. This review includes case studies from both anchialine and non-anchialine habitats, where evidence for in situ chemosynthetic production of organic matter and its subsequent transfer to higher trophic level metazoans is documented. The energy sources and pathways identified are synthesized to develop conceptual models for elemental cycles and energy cascades that occur within oligotrophic and eutrophic anchialine caves. Strategies and techniques for testing the hypothesis of chemosynthesis as an active process in anchialine caves are also suggested.

  15. Exposure of tour guides to Radon at the Cango caves

    International Nuclear Information System (INIS)

    Pule, O.J.; Lindsay, R.

    2008-01-01

    Full text: A study was commissioned by the National Nuclear Regulator of South Africa to investigate the radon levels in the Cango caves and the associated radiological exposure to tour guides. The Cango caves are about 1.3 km in length and are visited by about 300000 tourists per annum due to their natural beauty. This study followed an earlier investigation by the Department of Health which indicated levels in excess of 1000 Bqm -3 which could lead to excess exposure of the cave tour guides. Radon in the various cave chambers and radon exposure of tour guides was measured using RAD-7 continuous radon monitor, electrets ion chambers and personnel monitoring electrets respectively. The measurements in the cave were done during summer and winter seasons to determine any variations between the seasons. The occupancy time for individual guides and equilibrium factor were also investigated. The radon concentration in the cave range from 1000 Bqm -3 to more than 2000 Bqm -3 with equilibrium factor of approximately 0.4, and the variation between winter and summer measurements are insignificant. The radon exposure levels to tour guides differ due to various time periods they spent in the caves. The average dose to tour guides due to radon is 7 mSv -a and the highest exposure is about 10 mSv -a . The exposure to tourists is found to be insignificant due to time they spent in the cave. The regulatory authority is currently investigating what action is necessary to protect the tour guides. (author)

  16. Hurricane Impact on Seepage Water in Larga Cave, Puerto Rico

    Science.gov (United States)

    Vieten, Rolf; Warken, Sophie; Winter, Amos; Schröder-Ritzrau, Andrea; Scholz, Denis; Spötl, Christoph

    2018-03-01

    Hurricane-induced rainfall over Puerto Rico has characteristic δ18O values which are more negative than local rainfall events. Thus, hurricanes may be recorded in speleothems from Larga cave, Puerto Rico, as characteristic oxygen isotope excursions. Samples of 84 local rainfall events between 2012 and 2013 ranged from -6.2 to +0.3‰, whereas nine rainfall samples belonging to a rainband of hurricane Isaac (23-24 August 2012) ranged from -11.8 to -7.1‰. Cave monitoring covered the hurricane season of 2014 and investigated the impact of hurricane rainfall on drip water chemistry. δ18O values were measured in cumulative monthly rainwater samples above the cave. Inside the cave, δ18O values of instantaneous drip water samples were analyzed and drip rates were recorded at six drip sites. Most effective recharge appears to occur during the wet months (April-May and August-November). δ18O values of instantaneous drip water samples ranged from -3.5 to -2.4‰. In April 2014 and April 2015 some drip sites showed more negative δ18O values than the effective rainfall (-2.9‰), implying an influence of hurricane rainfall reaching the cave via stratified seepage flow months to years after the event. Speleothems from these drip sites in Larga cave have a high potential for paleotempestology studies.

  17. Cave-dwelling pholcid spiders (Araneae, Pholcidae: a review

    Directory of Open Access Journals (Sweden)

    Bernhard A. Huber

    2018-06-01

    Full Text Available Pholcidae are ubiquitous spiders in tropical and subtropical caves around the globe, yet very little is known about cave-dwelling pholcids beyond what is provided in taxonomic descriptions and faunistic papers. This paper provides a review based on a literature survey and unpublished information, while pointing out potential biases and promising future projects. A total of 473 native (i.e. non-introduced species of Pholcidae have been collected in about 1000 caves. The large majority of cave-dwelling pholcids are not troglomorphic; a list of 86 troglomorphic species is provided, including 21 eyeless species and 21 species with strongly reduced eyes. Most troglomorphic pholcids are representatives of only two genera: Anopsicus Chamberlin & Ivie, 1938 and Metagonia Simon, 1893. Mexico is by far the richest country in terms of troglomorphic pholcids, followed by several islands and mainland SE Asia. The apparent dominance of Mexico may partly be due to collectors’ and taxonomists’ biases. Most caves harbor only one pholcid species, but 91 caves harbor two and more species (up to five species. Most troglomorphic pholcids belong to two subfamilies (Modisiminae, Pholcinae, very few belong to Smeringopinae and Arteminae, none to Ninetinae. This is in agreement with the recent finding that within Pholcidae, microhabitat changes in general are concentrated in Modisiminae and Pholcinae.

  18. Cave monitoring in the Béke and Baradla caves (Northeastern Hungary: implications for the conditions for the formation cave carbonates

    Directory of Open Access Journals (Sweden)

    György Czuppon

    2018-01-01

    Full Text Available In order to use speleothems in the reconstruction of past climate and environmental changes it is necessary to understand the environmental and hydrological processes that determine the physico-chemical conditions of carbonate precipitation and hence speleothem formation. Therefore, in this study an extended monitoring program was conducted in the Béke and Baradla caves located in the Aggtelek region (Northeastern Hungary. The studied caves are rich in speleothem and flowstone occurrences with great potential for paleoclimatology studies. The monitoring activity included measurements of atmospheric and cave temperatures, CO2 concentration in cave air, as well as chemical and isotopic compositions of water samples (drip water, precipitation and in situ carbonate precipitates. The hydrogen and oxygen isotope compositions of drip waters showed no seasonal variation at any of the collection sites, indicating a well-mixed karstic aquifer. This implies that the isotopic compositions of local speleothems were able to record multiannual isotopic changes inherited from stable isotopes in the drip water. CO2 concentration showed seasonality (high values in summer and low values in winter in both caves, likely affecting carbonate precipitation or corrosion and consequently stalagmite growth. Systematic variations among Mg/Ca and Sr/Ca, Na/Ca, and Si/Ca element ratios were detected in the drip water suggesting Prior Calcite Precipitation (PCP. As PCP is characteristic of periods of reduced infiltration during drier weather conditions, the variations in drip water chemistry and drip rates indicate that the hydrological conditions also varied significantly during the studied period. This hydrological variability appears to affect not only trace element composition but also the isotopic composition of modern carbonate precipitates. In summary, these findings imply that the speleothems from the studied caves were able to record the hydrological changes

  19. Morphometry and distribution of isolated caves as a guide for phreatic and confined paleohydrological conditions

    Science.gov (United States)

    Frumkin, Amos; Fischhendler, Itay

    2005-04-01

    Isolated caves are a special cave type common in most karst terrains, formed by prolonged slow water flow where aggressivity is locally boosted. The morphometry and distribution of isolated caves are used here to reconstruct the paleohydrology of a karstic mountain range. Within a homogenous karstic rock sequence, two main types of isolated caves are distinguished, and each is associated with a special hydrogeologic setting: maze caves form by rising water in the confined zone of the aquifer, under the Mt. Scopus Group (Israel) confinement, while chamber caves are formed in phreatic conditions, apparently by lateral flow mixing with a vadose input from above.

  20. The WP-CAVE concept for an underground high-level nuclear waste repository

    International Nuclear Information System (INIS)

    Pettersson, G.

    1984-02-01

    A central, nearly spherical cave, of diameter 40 m is excavated in rock and the waste fuel is placed in it. The fuel canisters are placed in cylindrical holes in large concrete balls which are stored at the bottom of a central stack in the cave. Other empty balls fill the rest of the cave. By natural convection, the heat is evenly distributed in the cave and the surrounding central rock body. A clay barrier, which completely surrounds the rock body, prevents ground water circulation for a very long time and protects the cave against tectonic movements. The cave can store approx. 350 tons of fuel after the 10 years of intermediate storage

  1. Cure from the cave: volcanic cave actinomycetes and their potential in drug discovery

    Directory of Open Access Journals (Sweden)

    Cheeptham N.

    2013-01-01

    Full Text Available Volcanic caves have been little studied for their potential as sources of novel microbial species and bioactive compounds with new scaffolds. We present the f irst study of volcanic cave microbiology from Canada and suggest that this habitat has great potential for the isolation of novel bioactive substances. Sample locat ions were plot ted on a contour map that was compiled in ArcView 3.2. Over 400 bacterial isolates were obtained from the Helmcken Falls cave in Wells Gray Provincial Park, British Columbia. From our preliminary screen, of 400 isolates tested, 1% showed activity against extended spectrum ß-lactamase E. coli, 1.75% against Escherichia coli, 2.25% against Acinetobacter baumannii, and 26.50% against Klebsiella pneumoniae. In addition, 10.25% showed activity against Micrococcus luteus, 2% against methicillin resistant Staphylococcus aureus, 9.25% against Mycobacterium smegmatis, 6.25% Pseudomonas aeruginosa and 7.5% against Candida albicans. Chemical and physical characteristics of three rock wall samples were studied using scanning electron microscopy and f lame atomic absorption spectrometry. Calcium (Ca, iron (Fe, and aluminum (Al were the most abundant components while magnesium (Mg, sodium (Na, arsenic (As, lead (Pb, chromium (Cr, and barium (Ba were second most abundant with cadmium (Cd and potassium (K were the least abundant in our samples. Scanning electron microscopy (SEM showed the presence of microscopic life forms in all three rock wall samples. 16S rRNA gene sequencing of 82 isolates revealed that 65 (79.3% of the strains belong to the Streptomyces genus and 5 (6.1% were members of Bacillus, Pseudomonas, Nocardia and Erwinia genera. Interestingly, twelve (14.6% of the 16S rRNA sequences showed similarity to unidentif ied ribosomal RNA sequences in the library databases, the sequences of these isolates need to be further investigated using the EzTaxon-e database (http://eztaxon-e. ezbiocloud.net/ to determine whether

  2. Morphology and evolution of sulphuric acid caves in South Italy

    Science.gov (United States)

    D'Angeli, Ilenia M.; De Waele, Jo; Galdenzi, Sandro; Madonia, Giuliana; Parise, Mario; Vattano, Marco

    2016-04-01

    Sulphuric acid speleogenesis (SAS) related to the upwelling of acid water enriched in H2S and CO2 represents an unusual way of cave development. Since meteoric infiltration waters are not necessarily involved in speleogenesis, caves can form without the typical associated karst expressions (i.e. dolines) at the surface. The main mechanism of sulphuric acid dissolution is the oxidation of H2S (Jones et al., 2015) which can be amplified by bacterial mediation (Engel et al., 2004). In these conditions, carbonate dissolution associated with gypsum replacement, is generally believed to be faster than the normal epigenic one (De Waele et al., 2016). In Italy several SAS caves have been identified, but only few systems have been studied in detail: Frasassi and Acquasanta Terme (Marche)(Galdenzi et al., 2010), Monte Cucco (Umbria) (Galdenzi & Menichetti, 1995), and Montecchio (Tuscany) (Piccini et al., 2015). Other preliminary studies have been carried out in Calabria (Galdenzi, 2007) and Sicily (De Waele et al., 2016). Several less studied SAS cave systems located in South Italy, and in particular in Apulia (Santa Cesarea Terme), Sicily (Acqua Fitusa, Acqua Mintina) and Calabria (Mt. Sellaro and Cassano allo Ionio) have been selected in the framework of a PhD thesis on SAS caves and their speleogenesis. Using both limestone tablet weight loss (Galdenzi et al., 2012) and micro erosion meter (MEM) (Furlani et al., 2010) methods the dissolution rate above and under water in the caves will be quantified. Geomorphological observations, landscape analysis using GIS tools, and the analysis of gypsum and other secondary minerals (alunite and jarosite) (stable isotopes and dating) will help to reconstruct the speleogenetic stages of cave formation. Preliminary microbiological analysis will determine the microbial diversity and ecology in the biofilms. References Engel S.A., Stern L.A., Bennett P.C., 2004 - Microbial contributions to cave formation: New insight into sulfuric acid

  3. Radon measurements using track detector in Wadi Sannur cave

    International Nuclear Information System (INIS)

    Shahin, F.; Eissa, M.F.; Mostafa, R.M.

    2008-01-01

    The most important contributors to the committed effective dose received by population due to natural sources are the short-lived decay products of radon ( 222 Rn). In natural voids, such as caves, most radon will enter the system from diffusion across the rock-air interface. It is well known that factors such as air pressure and temperature control the distribution of radon. The radon concentration measurements in the Wadi Sannur cave in Beni-Suef governorate in the period from 14 th of July 2005 to 17 th of October 2005. The average radon concentrations in the right, left and whole first cave are 916.12 ± 179.09, 819.63 ± 54.72 and 873.90± 147.11 Bq m -3 respectively. The measurements were performed using track etch detector of type Cr-39. After exposure, all detectors were etched chemically in 6.25 M NaOH solution at 70 C degrees for 6 h. The tracks were counted with an optical microscope magnifying 400 times. The average temperature inside the first cave during the period of measurements is 25-26 C degrees. The annual effective doses for the workers and visitors in the cave have been calculated. The average radon concentration in the Wadi Sannur cave, was 873.90 ± 147.11 Bq m -3 . The annual effective doses for worker and visitor in the cave were 1.33 ± 0.24 and 0.041 ± 0.007 mSv respectively. The doses are within the international recommended dose of 1.15 mSv. (author)

  4. WP-Cave - assessment of feasibility, safety and development potential

    International Nuclear Information System (INIS)

    1989-09-01

    According to SKB R and D-programme 1986, alternative disposal methods will be investigated to provide a basis for selecting a site and a repository system for the Swedish spent nuclear fuel. The present report is a comparison between the WP-Cave and the reference concept KBS-3. The comparison has resulted in the following conclusions: - Both concepts are judged to be able to provide adequate safety. - A utilization of the potential of the WP-Cave requires, however, extensive development in areas where the current state of knowledge and available data are incomplete. - The higher temperatures in the WP-Cave lead to greater uncertainty as to long-term performance. Reducing this uncertainty would require many yaers of research and substantial resources. - Both repositories, including the barriers they incorporate, could be built with a normal adaption of available technology. -It is not possible to say today whether it would be simpler to find suitable sites for one design or the other. - The WP-Cave is considerably more expensive. A future research direction based on a concentrated emplacement of spent fuel along the lines of the WP-Cave is therefore judged to entail greater uncertainty as regards the possibilities of achieving acceptable safety and to require greater resources for research and development, at the same time as the costs of building the repository would be higher. The studies of the WP-Cave as an integral system should therfore be discontinued. Certain barrier designs in the WP-Cave could also be utulized in repository designs with lower temperature, for example the reduction potential of the steel canisters and the hydraulic cage's diversion of groundwater. Studies within these areas are being conducted within SKB and should continue

  5. Analysis of the Condition and Development Opportunities of Cave Tourism in Primorsko-Goranska County

    Directory of Open Access Journals (Sweden)

    Rade Knežević

    2011-04-01

    Full Text Available This paper examines caves as morphological factors of tourism development in Primorsko-Goranska County. The primary aim is to promote cave heritage parallel with the development of cave tourism. The methodological framework is based on analyzing material in the archives of tourist boards, taking an inventory of cave resources (case study, conducting interviews, and making a SWOT analysis of cave tourism development. Research results show that caves represent a complex resource in the tourist trade of Primorsko-Goranska County, to which little importance has been attached up to date (priority being given to mass tourism. In the context of tourism development, caves fall into four groups. The first group comprises caves that have a long tradition, but show signs of aging as a tourism product. The second group includes caves that were once open to the public, but were later closed for some reason. The third group consists of caves on the seaside or seabed visited by speleologists-divers. The fourth group is made up of potential cave sites that have been evaluated as being attractive, but is located in hard-to-access areas, making their valorisation in tourism purpose more difficult. Only Lokvarka Cave has a substantial influence on the development of special interest tourism in Lokve, while in all other cases, the role of caves in the tourism offering needs to be revalorised.

  6. Numerical simulation of formation and preservation of Ningwu ice cave, Shanxi, China

    Science.gov (United States)

    Yang, S.; Shi, Y.

    2015-10-01

    Ice caves exist in locations where annual average air temperature is higher than 0 °C. An example is Ningwu ice cave, Shanxi Province, the largest ice cave in China. In order to quantitatively investigate the mechanism of formation and preservation of the ice cave, we use the finite-element method to simulate the heat transfer process at this ice cave. There are two major control factors. First, there is the seasonal asymmetric heat transfer. Heat is transferred into the ice cave from outside very inefficiently by conduction in spring, summer and fall. In winter, thermal convection occurs that transfers heat very efficiently out of the ice cave, thus cooling it down. Secondly, ice-water phase change provides a heat barrier for heat transfer into the cave in summer. The calculation also helps to evaluate effects of global warming, tourists, colored lights, climatic conditions, etc. for sustainable development of the ice cave as a tourism resource. In some other ice caves in China, managers have installed airtight doors at these ice caves' entrances with the intention of "protecting" these caves, but this in fact prevents cooling in winter and these cave ices will entirely melt within tens of years.

  7. Paleo-watertable definition using cave ferromanganese stromatolites and associated cave-wall notches (Sierra de Arnero, Spain)

    Science.gov (United States)

    Rossi, Carlos; Villalaín, Juan J.; Lozano, Rafael P.; Hellstrom, John

    2016-05-01

    The steeply-dipping-dolostone-hosted caves of the Sierra de Arnero (N Spain) contain low-gradient relict canyons with up to ten mapped levels of ferromanganese stromatolites and associated wall notches over a vertical range of 85 m, the highest occurring 460 m above base level. Despite a plausible speleogenetic contribution by pyrite oxidation, and the irregular cave-wall mesomorphologies suggestive of hypogenic speleogenesis, the Arnero relict caves are dominantly epigenic, as indicated by the conduit pattern and the abundant allogenic sediments. Allogenic input declined over time due to a piracy-related decrease in the drainage area of allogenic streams, explaining the large size of the relict Arnero caves relative to the limited present-day outcrop area of the karstified carbonates. Allogenic-sediment input also explains the observed change from watertable canyons to phreatic conduits in the paleo-downstream direction. Stromatolites and notches arguably formed in cave-stream passages at the watertable. The best-defined paleo-watertables show an overall slope of 1.7°, consistent with the present-day relief of the watertable, with higher-slope segments caused by barriers related to sulfide mineralization. The formation of watertable stromatolites favored wall notching by the combined effect of enhanced acidity by Mn-Fe oxidation and shielding of cave floors against erosion. Abrasive bedload further contributed to notch formation by promoting lateral mechanical erosion and protecting passage floors. The irregular wallrock erosional forms of Arnero caves are related partly to paragenesis and partly to the porous nature of the host dolostones, which favored irregular dissolution near passage walls, generating friable halos. Subsequent mechanical erosion contributed to generate spongework patterns. The dolostone porosity also contributes to explain the paradox that virtually all Arnero caves are developed in dolostone despite being less soluble than adjacent

  8. Building 887: An Aladdin's Cave for Physicists

    CERN Multimedia

    2001-01-01

    Building 887 on the Prévessin site is home to numerous experiments bringing together physicists and engineers from around the world. Its diversity makes the huge building a replica of CERN in miniature. The Installation unit of the SL EA group in front of the support structure for the ATLAS muon chambers. From left to right, seated: Pierre Gimenez, Yves Bonnet, Yves Naveau, Alain Pinget, Christian Becquet, Camille Adenot; standing: Philippe Guillot, Thierry Reynes, Monserrat Zurita-Perez, Claude Ferrari et Denis Gacon. The big wheel to be used for the ATLAS muon chambers (see below) is much the most spectacular installation currently occupying Building 887. But it is far from being the only attraction. Push open the heavy doors of this immense hall and it is a bit like entering a physicists' Aladdin's cave. The building, 55 metres wide and 300 metres long, is a treasure trove of engineering and technology, a CERN in miniature, housing dozens of collaborations from all over the world. With its 150...

  9. Tamarugite from Diana Cave (SW Romania) -first true karst occurrence

    Science.gov (United States)

    Pušcaš, C. M.; Onac, B. P.; Effenberger, H. S.; Povarǎ, I.

    2012-04-01

    Diana Cave is located within the town limits of Baile Herculane (SW Romania) and develops as a 14 m long, westward oriented, unique passage guided by the Diana fault [1]. At the far end of the cave, the thermo-mineral Diana Spring wells forth. In the early 1970s a mine gallery that intersected the cave was created to drain the water into a pumping station and the original cave passage was somewhat altered and reinforced with concrete. Today the concrete and the silty limestone cave walls are heavily corroded by H2SO4 outgassing from the hot water (ca. 50°C) and display abundant gypsum crusts, soggy aggregates of native S, and a variety of more exotic sulfates. Among them, a mineral that has been previously identified in caves only in connection to volcanic activity, either as thermal springs or fumaroles [2]: tamarugite [NaAl(SO4)26H2O]. It was [3] that first mentioned the occurrence of this Na and Al sulfate in Diana Cave, our research aiming to give a detailed description of this mineral, its paragenesis, and mechanisms of precipitation. Recently, tamarugite has also been identified in a sulfuric acid cave from Greece [4]. Along with powder X-ray diffractions coupled with Rietveld refinement, scanning electron microscope, and electron probe micro-analysis, δ18O and δ34S compositions of the sulfate mineral as well as precipitates from the water were analyzed to identify and better constrain the genesis of this rare sulfate. Regrettably, the crystal size of our specimens is inappropriate for identification by means of single crystal X-ray diffraction. Physical and chemical parameters of Diana Spring were as well measured on several occasions. Geochemical analysis suggests that the minute, white tamarugite flakes precipitated in Diana Cave as a result of the interactions between the thermo-mineral water or water vapor and the original limestone bedrock and concrete that blankets the mine gallery. [1] Povara, I., Diaconu, G., Goran, C. (1972). Observations pr

  10. Cave exploitation by an usual epigean species: a review on the current knowledge on fire salamander breeding in cave

    Directory of Open Access Journals (Sweden)

    Raoul Manenti

    2017-11-01

    Full Text Available The fire salamander (Salamandra salamandra is a relatively common epigean amphibian, widely distributed throughout Europe, which usually gives birth to aquatic larvae. Even if epigean streams represent the most common places in which the species breeds, in some countries caves with underground waters are also used. To improve our understanding of the habitat features allowing successful breeding of salamanders in underground sites, we combined an exhaustive review of the available literature, especially the grey one, with direct observations performed from 2008 to 2017 in several natural and artificial caves of Lombardy, Liguria and Tuscany (Italy, Ariège and Provence (France. We provide a synthesis of published and unpublished caves in which the fire salamander breeding has been observed, along with a synthesis of the investigated ecological, behavioural and morphological traits. The use of underground sites is reported in several published papers and appears to be a common phenomenon not limited to single karst areas. The absence of predators, the relative stability of the aquatic habitats and the possibility to exploit new ecological resources are environmental factors that favour the breeding of the fire salamander. Our synthesis suggests that breeding of fire salamanders in caves is not a random event, but a widespread phenomenon that may be linked to specific biogeographical factors. Further insights may be obtained by performing genetic analyses on both cave and epigean populations, and considering larger landscape scales for ecological studies as well. Gene flow between salamanders that breed in caves and in streams probably occurs, but on the other hand, assortative mating might limit it, thus allowing the conservation of local adaptations driving successful cave colonisation.

  11. The CAVE (TM) automatic virtual environment: Characteristics and applications

    Science.gov (United States)

    Kenyon, Robert V.

    1995-01-01

    Virtual reality may best be defined as the wide-field presentation of computer-generated, multi-sensory information that tracks a user in real time. In addition to the more well-known modes of virtual reality -- head-mounted displays and boom-mounted displays -- the Electronic Visualization Laboratory at the University of Illinois at Chicago recently introduced a third mode: a room constructed from large screens on which the graphics are projected on to three walls and the floor. The CAVE is a multi-person, room sized, high resolution, 3D video and audio environment. Graphics are rear projected in stereo onto three walls and the floor, and viewed with stereo glasses. As a viewer wearing a location sensor moves within its display boundaries, the correct perspective and stereo projections of the environment are updated, and the image moves with and surrounds the viewer. The other viewers in the CAVE are like passengers in a bus, along for the ride. 'CAVE,' the name selected for the virtual reality theater, is both a recursive acronym (Cave Automatic Virtual Environment) and a reference to 'The Simile of the Cave' found in Plato's 'Republic,' in which the philosopher explores the ideas of perception, reality, and illusion. Plato used the analogy of a person facing the back of a cave alive with shadows that are his/her only basis for ideas of what real objects are. Rather than having evolved from video games or flight simulation, the CAVE has its motivation rooted in scientific visualization and the SIGGRAPH 92 Showcase effort. The CAVE was designed to be a useful tool for scientific visualization. The Showcase event was an experiment; the Showcase chair and committee advocated an environment for computational scientists to interactively present their research at a major professional conference in a one-to-many format on high-end workstations attached to large projection screens. The CAVE was developed as a 'virtual reality theater' with scientific content and

  12. Passive magnetic bearing configurations

    Science.gov (United States)

    Post, Richard F [Walnut Creek, CA

    2011-01-25

    A journal bearing provides vertical and radial stability to a rotor of a passive magnetic bearing system when the rotor is not rotating and when it is rotating. In the passive magnetic bearing system, the rotor has a vertical axis of rotation. Without the journal bearing, the rotor is vertically and radially unstable when stationary, and is vertically stable and radially unstable when rotating.

  13. Eastern Cave- and Crevice-Dwelling Bats Potentially Impacted by USACE Reservoir Operations

    National Research Council Canada - National Science Library

    Martin, C.O

    2002-01-01

    ...; Kasul, Martin, and Allen 2000). This note provides information on six species of forest bats that roost in caves or cave-like structures and potentially occur on Corps projects in the Eastern United States...

  14. The Evaluation of a Motion Base Driving Simulator in a Cave at TACOM

    National Research Council Canada - National Science Library

    Mollenhauer, M. A; Romano, R. A; Brumm, B

    2004-01-01

    The purpose of this presentation is to describe the highlights of a research program designed to investigate the feasibility of creating a motion base driving simulator in a Cave Automatic Virtual Environment (CAVE...

  15. The potential of perennial cave ice in isotope palaeoclimatology

    International Nuclear Information System (INIS)

    Yonge, Charles J.; MacDonald, William D.

    1999-01-01

    Perennial ice from caves on and to the east of the Canadian Great Divide yield delta O 18 and delta D values which are usually high measurements where compared with the average precipitation for the region. Furthermore, these ice data fall below and along lines of lower slope than the Global Meteoric Water Line. To explain the observed relationships, we propose the following process. a vapour-ice isotopic fractionation mechanism operates on warm season vapour when it precipitates as hoar ice on entering the caves. The subsequent fall of hoar to the cave floor through mechanical overloading along with ice derived from ground-water seepage (with a mean annual isotopic composition), results in massive ice formation of a mixed composition. This mixed composition is what is observed in the characteristic relationships found here. Such findings suggest that a warm versus cold climate interpretation for ancient cave ice may be the opposite of that found in the more familiar polar and glacial ice caves. (Author) 3 figs., 1 tab., 12 refs

  16. Structural and hydrological controls on the development of a river cave in marble (Tapagem Cave - SE Brazil

    Directory of Open Access Journals (Sweden)

    William Sallun Filho

    2015-01-01

    Full Text Available Tapagem Cave (or Devil’s Cave is a river cave developed in the dolomite marble karst of the Serra do André Lopes (State of São Paulo, southeastern Brazil. Although this region is a plateau with significant variation in elevation and a humid subtropical climate, the cave is an anomalous feature in the André Lopes karst because there are few other caves. The marble, which is in a synclinal structure with subjacent phyllites, is a karst aquifer perched above the regional base level (Ribeira River and has little allogenic recharge. The cave developed on a secondary anticline on the northwest flank of the marble synform forming a blind valley, the Tapagem River sink, that is an underground tributary of Ostras River. Development of the cave is due to the entrenchment of the Ostras through-valley and the large allogenic catchment area of the sink. In plan view, the morphology of the cave can be divided into three different sectors. The first sector, known as the Tourist Sector, has extensive collapse rooms, fossil passages and a variety of speleothems of notable dimensions. The second and most extensive sector is the river passage, which is a sinuous gallery controlled by marble banding with NE-SW cleavage and NW-SE fractures. In cross-section, the passages are vadose canyons up to 70 m in height, controlled by the marble banding. Four NW-SE diabase dykes in this passage do not affect its direction in plan view. The third sector is an extensive network of passages and collapse rooms, which are interlaced in plan view and on different levels, forming a maze pattern. Initially, the Tapagem and Ostras Rivers developed on a gentle surface and flowed into the Ribeira River. With the entrenchment of the Ostras through-valley, the Tapagem River partially infiltrated via a paleosink into the upper passage of the “Erectus Room," remaining a half-blind valley. Following a series of collapses and obstructions, the River next infiltrated via the current

  17. A review of factors affecting cave climates for hibernating bats in temperate North America

    Science.gov (United States)

    Roger W. Perry

    2013-01-01

    The fungal pathogen Geomyces destructans, which causes white-nose syndrome in bats, thrives in the cold and moist conditions found in caves where bats hibernate. To aid managers and researchers address this disease, an updated and accessible review of cave hibernacula and cave microclimates is presented. To maximize energy savings and reduce...

  18. A Framework for Aligning Instructional Design Strategies with Affordances of CAVE Immersive Virtual Reality Systems

    Science.gov (United States)

    Ritz, Leah T.; Buss, Alan R.

    2016-01-01

    Increasing availability of immersive virtual reality (IVR) systems, such as the Cave Automatic Virtual Environment (CAVE) and head-mounted displays, for use in education contexts is providing new opportunities and challenges for instructional designers. By highlighting the affordances of IVR specific to the CAVE, the authors emphasize the…

  19. Guanophilic fungi in three caves of southwestern Puerto Rico

    Directory of Open Access Journals (Sweden)

    Nieves-Rivera Angel M.

    2009-01-01

    Full Text Available Fifty species of guanophilic (bat guano-loving fungi were isolated from field-collected samples within three caves in southwesternPuerto Rico; most were mitosporic fungi (23 species. The caves studied were Cueva La Tuna (Cabo Rojo, Cueva de Malano(Sistema de Los Chorros, San Germán, and Cueva Viento (El Convento Cave-Spring System, Guayanilla-Peñuelas. The mostconspicuous fungus by far was the zygomycete Circinella umbellata (Mucorales. Circinella umbellata dominated the bat guanoincubation chambers (Petri dishes lined with sterile filter paper moistened with sterile water at ambient laboratory conditions.Nineteen species of basidiomycetes (e.g., Ganoderma cf. resinaceum, Geastrum cf. minimum, Lepiota sp., Polyporus sp., Ramariasp. and three species of ascomycetes (Hypoxylon sp., Xylaria anisopleura, and X. kegeliana were also recorded. They were foundon soil, rotting leaves, bark and rotting wood, buried in bat guano located below natural skylights or sinkholes.

  20. The chronology of Moncks Cave, Canterbury, New Zealand

    International Nuclear Information System (INIS)

    Jacomb, C.

    2008-01-01

    Moncks Cave is a key site in understanding the nature and course of change to Maori culture during the early period of New Zealand prehistory because of the range of both perishable and non-perishable artefacts found there in 1889. Understood to have been completely excavated at that time, the interpretation of the material culture of the site has been rendered difficult by the absence of chronological or stratigraphic provenance data. Recent investigations at Moncks Cave revealed several intact cultural deposits, including both faunal and artefactual remains. Eleven radiocarbon determinations on marine shell suggest that the cave was occupied some time between the mid-fourteenth and mid-fifteenth centuries AD. Although the dates cannot be directly correlated with any particular artefact, the results have important implications for the interpretation of the place of the site and its contents as a whole in the context of the New Zealand prehistoric sequence. (author). 22 refs., 5 figs., 1 tab

  1. Radon and thoron in cave dwellings (Yan'an, China)

    International Nuclear Information System (INIS)

    Wiegand, J.; Feige, S.; Xie Quingling; Schreiber, U.; Wieditz, K.; Wittmann, C.; Luo Xiarong

    2000-01-01

    222 Rn and 220 Rn concentrations were measured in cave dwellings and brick houses in the region of Yan'an (China) during summer 1997. The underground dwellings are built into Quaternary loess, and all investigated houses are founded on it. The median values of indoor 222 Rn and 220 Rn concentrations are 42 (n = 18) and 77Bq m -3 (n = 15) for brick houses and 92 (n = 23) and 215 (n = 17) Bq m -3 for cave dwellings. To classify the dwellings in respect to their cave-character, the fraction of walls having a direct contact to the loess is calculated for each dwelling. While the 222 Rn concentrations are increasing with higher fractions, the 220 Rn concentrations are not correlated with this fraction. On the other hand, due to the short half-life of 220 Rn the distance from the measuring point to the walls is negatively correlated with the 220 Rn concentration, while there is no correlation with the 222 Rn concentration. Therefore, concentric isolines of 220 Rn concentrations showing a strong gradient were detected in cave dwellings. An influence of the ventilation rate is distinct for 222 Rn but weak for 220 Rn. The effective dose rates for 222 Rn and 220 Rn and their progenies are calculated for brick houses (2.7 mSv y -1 ), cave dwellings (7.1 mSv y -1 ), and for traditional cave dwellings with a bed foundation built with loess (16.7 mSv y -1 ). These calculations are based on summer measurements only. It is expected that the true effective dose rates will be significantly higher

  2. Secondary sulfate minerals from Alum Cave Bluff: Microscopy and microanalysis

    Energy Technology Data Exchange (ETDEWEB)

    Lauf, R.J.

    1997-07-01

    Microcrystals of secondary sulfate minerals from Alum Cave Bluff, Great Smoky Mountains National Park, were examined by scanning electron microscopy and identified by X-ray fluorescence (XRF) in the SEM. Among the samples the author discovered three new rare-earth sulfates: coskrenite-(Ce), levinsonite-(Y), and zugshunstite-(Ce). Other minerals illustrated in this report include sulfur, tschermigite, gypsum, epsomite, melanterite, halotrichite, apjohnite, jarosite, slavikite, magnesiocopiapite, and diadochite. Additional specimens whose identification is more tentative include pickeringite, aluminite, basaluminite, and botryogen. Alum Cave is a ``Dana locality`` for apjohnite and potash alum, and is the first documented North American occurrence of slavikite.

  3. A radon survey performed in caves in Slovenia

    International Nuclear Information System (INIS)

    Jovanovic, P.

    2002-01-01

    A survey of radon and radon decay product concentrations in several caves in a limestone region in Slovenia was initiated in 1986. In the period from 1989 to 1998, monthly surveys were undertaken in several caves which are open to tourists or used for speleotherapy purposes. The reason for carrying out these surveys, were dose estimates obtained for the guides and medical staff working in the caves. Daily average radon gas concentration determined ranged from several 100 Bq/m 3 up to 27 kBq/m 3 . Higher values were measured in the summer period. The equilibrium factors derived ranged from 0.05 to 0.89, with the higher values being measured in the winter period in vertical caves. In horizontal caves (with two entrances located opposite one another) these values ranged between 0.55 and 0.89. Annual doses estimated on the basis of various lung models ranged from 10 mSv to 85 mSv per year and per 2000 working hours. A significant difference was observed between the doses estimated by means of dosimetric models, and those estimated on the basis of the epidemiological model presented in ICRP 65. The value for the unattached fraction indicated in ICRP 65 is about 3%, but our measurements performed in the caves yielded higher values of up to 15%, with this highest value being determined in the Postojna cave. In the coming years, we will perform measurements to obtain the values for concentrations of unattached particles of radon daughters and values for particle-size distribution in the 3 different caves with the highest occupancy times for visitors. There are no regulations in force in Slovenia affecting exposures to elevated radon and radon daughter concentrations among underground workers. The health inspectorate can impose radiation monitoring measures for the purposes of performing dose calculations for underground workers. The results from such monitoring measures will contribute to the establishment of an ordinance regulating the performance of measurements at low

  4. Mechanical characteristics of fully mechanized top-coal caving face and surrounding rock stress shell

    Energy Technology Data Exchange (ETDEWEB)

    Xie Guang-xiang [Anhui University of Science and Technology, Huainan (China)

    2005-06-15

    The distribution of surrounding rock stress in fully mechanized top-coal caving (FMTC) face was fully researched by large-scale and non-linear three-dimensional numerical simulation and equivalent laboratory. The results show that, there is the structure that is made of macroscopical stress shell composed of high stress binds in overlying strata of FMTC face. Stress shell, which bears and pass load of overlying strata, is primary supporting body. The stress in skewback of stress shell forms abutment pressure of surrounding rock in vicinity of working face. Bond-beam structure lies in reducing zone under stress shell. It only bear partial burden of strata under stress shell. The uppermost mechanical characteristic of FMTC face is lying in the low stress area under stress shell. It is the essential cause of strata behaviors of FMTC face relaxation. On the basis of analyzing stress shell, the mechanical essence that top coal performs a function of bedding is demonstrated. 4 refs., 7 figs.

  5. Differences between caves with and without bats in a Brazilian karst habitat

    Directory of Open Access Journals (Sweden)

    Camila G. Torquetti

    2017-10-01

    Full Text Available ABSTRACT. Since bats shelter in roosts during their period of diurnal inactivity, the quality and availability of roosts are important aspects of their ecology. Karst areas have great potential for the availability of day roosts, since they form caves, which serve as bat shelters. Here we characterize the caves used by bats in a preserved karst area of Southeastern Brazil. Using logistic regression analysis we identified the cave characteristics that influence bat occupation. Sixty-six caves were characterized based on measurements of internal height and width, height and width of the entrance(s of the cave, number of entrances, maximum horizontal development of cave, and internal temperature and humidity. In nineteen months we found 14 species in 32 caves. Most species were eventually recorded in multiple caves, with the exception of D. rotundus, G. soricina and A. planirostris, which were always found in the same caves. Desmodus rotundus showed maternity roost fidelity. We found no differences in microclimate between the caves that are occupied and those that are not. In other words, the microclimate of the caves studied herein can be characterized as stable over the years. The only predictor affecting the presence of bats in the study area was the cave’s maximum horizontal development: the caves that are occupied have greater horizontal development. Based on our results, we conclude that bats occupy many of the caves and that some species are more frequent in certain caves than in others, including some roosts that are used as maternity roosts. These findings indicate that these caves are important resources for the bats in the karst environment studied, and should be preserved.

  6. Luminescence chronology of cave sediments at the Atapuerca paleoanthropological site, Spain.

    Science.gov (United States)

    Berger, G W; Pérez-González, A; Carbonell, E; Arsuaga, J L; Bermúdez de Castro, J-M; Ku, T-L

    2008-08-01

    Ascertaining the timing of the peopling of Europe, after the first out-of-Africa demographic expansion at the end of the Pliocene, is of great interest to paleoanthropologists. One of the earliest direct evidences for fossil hominins in western Europe comes from an infilled karstic cave site called Gran Dolina at Atapuerca, in a stratum approximately 1.5m below the Brunhes-Matuyama (B-M) geomagnetic boundary (780ka) within lithostratigraphic unit TD6. However, most of the meters of fossil- and tool-bearing strata at Gran Dolina have been difficult to date. Therefore, we applied both thermoluminescence (TL) and infrared-stimulated-luminescence (IRSL) multi-aliquot dating methods to fine-silt fractions from sediment samples within Gran Dolina and the nearby Galería cave site. We also applied these methods to samples from the present-day surface soils on the surrounding limestone hill slopes to test the luminescence-clock-zeroing-by-daylight assumption. Within the uppermost 4m of the cave deposits at Gran Dolina, TL and paired TL and IRSL ages range stratigraphically from 198+/-19ka to 244+/-26ka. Throughout Gran Dolina, all luminescence results are stratigraphically self-consistent and, excepting results from two stratigraphic units, are consistent with prior ESR-U-series ages from progressively deeper strata. Thermoluminescence ages culminate at 960+/-120ka approximately 1m below the 780ka B-M boundary. At Galería, with one exception, TL and IRSL ages range stratigraphically downward from 185+/-26ka to 503+/-95ka at the base of the lowermost surface-inwash facies. These results indicate that TL and (sometimes) IRSL are useful dating tools for karstic inwash sediments older than ca. 100ka, and that a more accurate chronostratigraphic correlation is now possible among the main Atapuerca sites (Gran Dolina, Galería, Sima de los Huesos). Furthermore, the oldest TL age of ca. 960ka from Gran Dolina, consistent with biostratigraphic and paleomagnetic evidence, implies

  7. Study of aerosols collected in a speleotherapeutic cave situated below Budapest, Hungary

    Energy Technology Data Exchange (ETDEWEB)

    Kertesz, Zs. E-mail: zsofi@moon.atomki.hu; Borbely-Kiss, I.; Hunyadi, I

    1999-04-02

    The Szemlohegy-cave is one of the well-known hydrothermal caves of the Rozsadomb area of Budapest, which have been used for speleotherapy of respiratory diseases for years. It is known from the periodically changing airborne radon activity concentration data, that airflow of seasonally reversed direction are formed along the cave passages and fissures due to the temperature difference between the surface and cave air. This means that an intensive interaction takes place between the cave and its environment. The pollution of nearby waters and the urban atmospheric air represents a real danger for these caves below Buda, which recently became the part of the UNESCO World Heritage. The study of cave aerosols should be very important from the point of view of either the control possibilities of the environmental impact or speleotherapy, and probably helps in getting acquainted with the cave-forming processes. In this work we applied our standard aerosol sampling method to the high-humidity environment of the caves, and we studied the elemental composition, size fractionation as well as the spatial distribution and the seasonal variation of cave aerosols. Thanks to the sensitivity of PIXE traces of anthropogenic pollution of the Budapest air are shown in the Szemlohegy-cave. Measured elemental concentrations remained less than one-tenth the air quality standard valid for the increasingly protected areas.

  8. Study of aerosols collected in a speleotherapeutic cave situated below Budapest, Hungary

    International Nuclear Information System (INIS)

    Kertesz, Zs.; Borbely-Kiss, I.; Hunyadi, I.

    1999-01-01

    The Szemlohegy-cave is one of the well-known hydrothermal caves of the Rozsadomb area of Budapest, which have been used for speleotherapy of respiratory diseases for years. It is known from the periodically changing airborne radon activity concentration data, that airflow of seasonally reversed direction are formed along the cave passages and fissures due to the temperature difference between the surface and cave air. This means that an intensive interaction takes place between the cave and its environment. The pollution of nearby waters and the urban atmospheric air represents a real danger for these caves below Buda, which recently became the part of the UNESCO World Heritage. The study of cave aerosols should be very important from the point of view of either the control possibilities of the environmental impact or speleotherapy, and probably helps in getting acquainted with the cave-forming processes. In this work we applied our standard aerosol sampling method to the high-humidity environment of the caves, and we studied the elemental composition, size fractionation as well as the spatial distribution and the seasonal variation of cave aerosols. Thanks to the sensitivity of PIXE traces of anthropogenic pollution of the Budapest air are shown in the Szemlohegy-cave. Measured elemental concentrations remained less than one-tenth the air quality standard valid for the increasingly protected areas

  9. Profiling bacterial diversity in a limestone cave of the western Loess Plateau of China

    Directory of Open Access Journals (Sweden)

    Yucheng eWu

    2015-03-01

    Full Text Available Bacteria and archaea sustain subsurface cave ecosystems by dominating primary production and fueling biogeochemical cyclings, despite the permanent darkness and shortage of nutrients. However, the heterogeneity and underlying mechanism of microbial diversity in caves, in particular those well connect to surface environment are largely unexplored. In this study, we examined the bacterial abundance and composition in Jinjia Cave, a small and shallow limestone cave located on the western Loess Plateau of China, by enumerating and pyrosequencing small subunit (SSU rRNA genes. The results clearly reveal the contrasting bacterial community compositions in relation to cave habitat types, i.e., rock wall deposit, aquatic sediment and sinkhole soil, which are differentially connected to the surface environment. The deposits on the cave walls were dominated by putative cave-specific bacterial lineages within the -Proteobacteria or Actinobacteria that are routinely found on cave rocks around the world. In addition, sequence identity with known functional groups suggests enrichments of chemolithotrophic bacteria potentially involved in autotrophic C fixation and inorganic N transformation on rock surfaces. By contrast, bacterial communities in aquatic sediments were more closely related to those in the overlying soils. This is consistent with the similarity in elemental composition between the cave sediment and the overlying soil, implicating the influence of mineral chemistry on cave microhabitat and bacterial composition. These findings provide compelling molecular evidence of the bacterial community heterogeneity in an East Asian cave, which might be controlled by both subsurface and surface environments.

  10. Characterization and management trends of negative and positive impacts of tourism in show caves

    Directory of Open Access Journals (Sweden)

    Heros Augusto Santos Lobo

    2015-08-01

    Full Text Available Caves are one of the most fragile environments on Earth ’s surface, in function of physical, atmospheric and biological specificities. The natural characteristics associated with cultural aspects of local people are the reasons to tourist potential of caves. However, the tourist use of caves can generate negative impacts on the environment. This consequence happens when inappropriate procedures of planning and management of tourism are used. Negative impacts are described in this review, as also indications of management techniques to avoid, decrease or eliminate the negative consequences of tourism in caves. Positive impacts are also presented, in order to achieve a sustainable tourism in show caves. The conclusion argues that the negative impacts should not be considered as impediments to tourism in caves. It is important to know these impacts and use it as a key to get previous answers which allow to raise the sustainability of show caves.

  11. The architectural form of Qikou Cave dwellings in Chinese "Earth" culture

    Science.gov (United States)

    Chen, Xuanchen; Feng, Xinqun

    2018-03-01

    Cave building is not only a kind of architecture with unique style, but also a manifestation of Chinese traditional culture. Cave culture is an important part of Chinese traditional culture. The main purpose of this thesis which studies the architectural form of Qikou Cave, is to analyze how the cave building plays a positive role in promoting the development and application of modern resources and in cultural transmission. Based on a large amount of literature material, and taking Qikou Cave as an example, by studying the morphological characteristics of cave building, the paper takes an optimistic outlook on its future development and the sustainable development of the resources. It is expected that the cave culture can be further explored to promote the traditional Chinese culture and to drive the development of modern construction industry and resource conservation.

  12. Main karst and caves of Switzerland; El karst y las cuevas mas importantes de Suiza

    Energy Technology Data Exchange (ETDEWEB)

    Jeannin, P. Y.

    2016-07-01

    This paper presents an overview of the main karst areas and cave systems in Switzerland. The first part encloses descriptions of the main geological units that hold karst and caves in the country and summarizes a brief history of research and protection of the cave environments. The second part presents three regions enclosing large cave systems. Two regions in the Alps enclose some of the largest limestone caves in Europe: Siebenhengste (Siebenhengste cave system with ∼160 km and Barenschacht with 70 km) and Bodmeren-Silberen (Holloch cave system with 200 km and Silberen System with 39 km). These systems are also among the deepest with depths ranging between 880 and 1340 m. The third example is from the Jura Mountains (northern Switzerland). (Author)

  13. Late Holocene climate and environmental change from Asiul cave speleothems: interpretations in light of modern cave monitoring.

    Science.gov (United States)

    Smith, Andrew; Wynn, Peter; Barker, Philip; Leng, Melanie; Noble, Steve; Tych, Wlodek

    2017-04-01

    Northern Iberia offers an excellent location to study fluctuations in North Atlantic Ocean (NA) conditions and the impact that changes in the NA have on atmospheric systems, which dominate Europe's climate. Two speleothems from Cueva de Asiul (Matienzo, N. Spain) have been used to reconstruct rainfall variability in N. Spain throughout the Holocene (Smith et al., 2016a). The carbonate δ18O records from these speleothems are interpreted in the light of a rigorous modern cave monitoring program undertaken at Cueva de Asiul (Smith et al., 2016b). Drip water δ18O reflects a modern rainfall amount effect whilst δ13C appears influenced by Prior Calcite Precipitation (PCP) in the short term and changes in vegetation at long timescales. The speleothem δ18O shows that long duration ( 1500 year) cycles in wetting and drying are prevalent in N. Spain during the Holocene and that dry climate phases are related to the timing of cold events (Bond et al., 2001) in the NA. Here we look in more detail at one of these speleothems, assessing both δ18O and δ13C during the last two thousand years. We show that Cueva de Asiul speleothems not only preserve long duration climate cycles in δ18O, but that they also appear influenced by shorter duration changes in the North Atlantic Oscillation (NAO), in-sync with other NAO archives (Olsen et al., 2012). However, the Cueva de Asiul record does not appear to preserve a predominately positive NAO signal during the Medieval Climate Anomaly (MCA) as is common within many European archives (Trouet et al., 2009), possibly due to the sites' close proximity to the NA and localised oceanic weather systems (Moreno et al., 2012). Alongside climatic changes, the speleothem δ13C shows a clear transition toward higher isotope values around 360 years BP (BP=1950), signalling a major environmental change in the region possibly due to anthropogenic removal of vast swathes of natural forest to support ship building and industry related to the Spanish

  14. Blow Hole Cave: An unroofed cave on San Salvador Island, the Bahamas, and its importance for detection of paleokarst caves on fossil carbonate platforms

    Czech Academy of Sciences Publication Activity Database

    Bosák, Pavel; Mylroie, J. E.; Hladil, Jindřich; Carew, J. L.; Slavík, Ladislav

    2002-01-01

    Roč. 31, č. 3 (2002), s. 51-74 ISSN 0583-6050. [Karstological School - Classical Karst: Types of Karst /10./. Pstojna, 26.06.2002-28.06.2002] R&D Projects: GA AV ČR IAA3013809; GA AV ČR IAA3013209 Keywords : carbonate platforms * unroofed caves * gamma-ray spectrometry and wellogging Subject RIV: DB - Geology ; Mineralogy http://carsologica.zrc-sazu.si/downloads/313/slavik.pdf

  15. Teddy Bear Stories

    DEFF Research Database (Denmark)

    van Leeuwen, Theo; Caldas-Coulthardt, Carmen

    2014-01-01

    This paper presents a semiotic analysis of a key cultural artefact, the teddy bear. After introducing the iconography of the teddy bear, it analyses different kinds of stories to show how teddy bears are endowed with meaning in everyday life: stories from children's books, reminiscenses by adults...... bears have traditionally centred on interpersonal relations within the nuclear family, but have recently been institutionalized and commercialized....

  16. Bioaccumulation of eight heavy metals in cave animals from Dashui ...

    African Journals Online (AJOL)

    The results showed that zinc contents in Porcellio scaber from Dashui and Malang caves were 448.80 and 598.00 mg/kg, respectively, which is the highest among all these 8 metals, while Pb was not detected in Diestrammena marmorata and Rhinolophidae pearsoni, suggesting that both animals were incapable of or poor ...

  17. Mineral magnetic environmental record in clastic cave deposits

    Czech Academy of Sciences Publication Activity Database

    Šlechta, Stanislav; Kadlec, Jaroslav

    2008-01-01

    Roč. 38, special issue (2008), s. 134-134 ISSN 1335-2806. [Paleo, Rock and Environmental Magnetism. Castle Meeting /11./. 22.06.2008-28.06.2008, Bojnice] Institutional research plan: CEZ:AV0Z30130516 Keywords : mineral magnetic environmental reconstruction * cave sediments * Moravian Karst Subject RIV: DE - Earth Magnetism, Geodesy, Geography

  18. Study of firedamp release in sub-level caving

    Energy Technology Data Exchange (ETDEWEB)

    Castano, F.S.; Sanz Delgado, M.A.; Iturriaga Trenor, S.; Alberdi Vinas, C.

    1988-01-01

    The field work developed in the pits of 'Hullera Vasco-Leonesa' in Santa Lucia (Leon) to control firedamp release is described. Conclusions obtained concerning gas emission, irregularity and firedamp balance in sub-level caving winning faces are discussed. Some definitions of basic concepts in firedamp studies are also included. 7 figs.

  19. Full Immersive Virtual Environment Cave[TM] in Chemistry Education

    Science.gov (United States)

    Limniou, M.; Roberts, D.; Papadopoulos, N.

    2008-01-01

    By comparing two-dimensional (2D) chemical animations designed for computer's desktop with three-dimensional (3D) chemical animations designed for the full immersive virtual reality environment CAVE[TM] we studied how virtual reality environments could raise student's interest and motivation for learning. By using the 3ds max[TM], we can visualize…

  20. Inside the neutrino cave, close to the target complex

    CERN Multimedia

    CERN PhotoLab

    1976-01-01

    The photo shows on the left the shielding of the target complex, T9 and T11 for the wide and narrow beams. The direction of the primary proton beam faces the camera. Between the shielding and the cave wall are housed the magnets cooling pipes. The pulley block allows displacements inside the shielding.

  1. Incidence of chromosomal aberrations and micronuclei in cave tour guides.

    Science.gov (United States)

    Bilban, M; Bilban-Jakopin, C; Vrhovec, S

    2001-01-01

    An analysis of structural chromosomal aberrations (SCA) and micronucleus tests (MN) were performed in 38 subjects, cave tour guides and in appropriate control group. The dominant type of chromosomal aberrations in tourist guides were chromosomal breaks (0.013 per cell) and acentric fragments (0.011 per cell). In the control group, these aberrations were present up to 0.008 on cells. Considering the analysed cells of the guides in total (33,556), the incidence of dicentric and rings range is below 0.0008 on cells, even though three dicentric and ring chromosoms were found already in the first 1000 in vitro metaphases of some guides. Only 0.0003 dicentrics and neither other translocations were found in control group (ambiental exposure). The incidence of micronuclei in cytokinesis blocked lymphocytes ranged from 12-32 per 500 CB cells in the cave tour guides and from 4-11 per 500 CB cells in control group. Measurements of radon and its daughters were performed at different locations in the cave. Annual doses from 40-60 mSv were estimated per 2000 work hours for cave guides. The changes found in the genome of somatic cells may be related to the exposure doses of radon and its daughters, although smoking should not be ignored.

  2. Radon in Austrian tourist mines and show caves

    International Nuclear Information System (INIS)

    Ringer, W.; Graeser, J.

    2009-01-01

    The radon situation in tourist mines and show caves is barely investigated in Austria. This paper investigates the influence of its determining factors, such as climate, structure and geology. For this purpose, long-term time-resolved measurements over 6 to 12 months in 4 tourist mines and 2 show caves - with 5 to 9 measuring points each - have been carried out to obtain the course of radon concentration throughout the year. In addition, temperature and air-pressure were measured and compared to the data outside where available. Results suggest that the dominating factors of the average radon concentration are structure and location (geology) of the tunnel-system, whereas the diurnal and annual variation is mainly caused by the changing airflow, which is driven by the difference in temperature inside and outside. Downcast air is connected with very low radon concentrations, upcast air with high concentrations. In some locations the maximum values appear when the airflow ceases. But airflow can be different in different parts of mines and caves. Systems close to the surface show generally lower radon levels than the ones located deeper underground. Due to variation of structure, geology and local climate, the radon situation in mines and caves can only be described by simultaneous measurements at several measuring points. (orig.)

  3. Preliminary study of radioactive waste disposal in granitic underground caves

    International Nuclear Information System (INIS)

    Carvalho, J.F. de; Carajilescov, P.

    1984-01-01

    To date, the disposal of radioactive wastes is one of the major problems faced by the nuclear industry. The utilization of granitic underground caves surrounded by a clay envelope is suggested as a safe alternative for such disposal. A preliminary analysis of the dimensions of those deposits is done. (Author) [pt

  4. Energy and speleogenesis: Key determinants of terrestrial species richness in caves.

    Science.gov (United States)

    Jiménez-Valverde, Alberto; Sendra, Alberto; Garay, Policarp; Reboleira, Ana Sofia P S

    2017-12-01

    The aim of this study was to unravel the relative role played by speleogenesis (i.e., the process in which a cave is formed), landscape-scale variables, and geophysical factors in the determination of species richness in caves. Biological inventories from 21 caves located in the southeastern Iberian Peninsula along with partial least square (PLS) regression analysis were used to assess the relative importance of the different explanatory variables. The caves were grouped according to the similarity in their species composition; the effect that spatial distance could have on similarity was also studied using correlation between matrices. The energy and speleogenesis of caves accounted for 44.3% of the variation in species richness. The trophic level of each cave was the most significant factor in PLS regression analysis, and epigenic caves (i.e., those formed by the action of percolating water) had significantly more species than hypogenic ones (i.e., those formed by the action of upward flows in confined aquifers). Dissimilarity among the caves was very high (multiple-site β sim  = 0.92). Two main groups of caves were revealed through the cluster analysis, one formed by the western caves and the other by the eastern ones. The significant-but low-correlation found between faunistic dissimilarity and geographical distance ( r  =   .16) disappeared once the caves were split into the two groups. The extreme beta-diversity suggests a very low connection among the caves and/or a very low dispersal capacity of the species. In the region under study, two main factors are intimately related to the richness of terrestrial subterranean species in caves: the amount of organic material (trophic level) and the formation process (genesis). This is the first time that the history of a cave genesis has been quantitatively considered to assess its importance in explaining richness patterns in comparison with other factors more widely recognized.

  5. A multi-proxy reconstruction of Holocene climate change from Blessberg Cave, Germany

    Science.gov (United States)

    Breitenbach, Sebastian F. M.; Plessen, Birgit; Wenz, Sarah; Leonhardt, Jens; Tjallingii, Rik; Scholz, Denis; Jochum, Klaus Peter; Marwan, Norbert

    2016-04-01

    Although Holocene climate dynamics were relatively stable compared to glacial conditions, climatic changes had significant impact on ecosystems and human society on various timescales (Mayewski et al. 2004, Donges et al. 2015, Tan et al. 2015). Precious few high-resolution records on Holocene temperature and precipitation conditions in Central Europe are available (e.g., von Grafenstein et al. 1999, Fohlmeister et al. 2012). Here we present a speleothem-based reconstruction of past climate dynamics from Blessberg Cave, Thuringia, central Germany. Three calcitic stalagmites were recovered when the cave was discovered during tunneling operations in 2008. Samples BB-1, -2 and -3 were precisely dated by the 230Th/U-method, with errors between 10 and 160 years (2σ). The combined record covers large parts of the Holocene (10 - 0.4 ka BP). δ13C and δ18O were analysed at 100 μm resolution. To gain additional insights in infiltration conditions, Sr/Ca and S/Ca were measured on BB-1 and BB-3 using an Röntgenanalytik Eagle XXL μXRF scanner. Differences to other central European records (e.g., von Grafenstein et al. 1999, Fohlmeister et al. 2012) suggest complex interaction between multiple factors influencing speleothem δ18O in Blessberg Cave. Furthermore, no clear influence of the North Atlantic Oscillation on our proxies is found. However, a link across the N Atlantic realm is indicated by a centennial-scale correlation between Blessberg δ18O values and minerogenic input into lake SS1220 in Greenland over the last 5 ka (Olsen et al. 2012). In addition, recurrence analysis indicates an imprint of Atlantic Bond events on Blessberg δ18O values (Marwan et al. 2014), corroborating the suggested link with high northern latitudes. Larger runoff into the Greenland lake seems to be associated with lower δ18O, higher δ13C and S/Ca ratios, as well as lower Sr/Ca ratios in Blessberg Cave speleothems. This might be linked to lower local temperature and/or changes in

  6. Palaeoclimate Research in Villars Cave (Dordogne, SW-France

    Directory of Open Access Journals (Sweden)

    Genty Dominique

    2008-10-01

    Full Text Available Villars Cave is a typical shallow cave from South-West France (45.44°N; 0.78°E; 175 m asl that has provided several speleothempalaeoclimatic records such as the millennial scale variability of the Last Glacial period and the Last Deglaciation. Monitoring theVillars cave environment over a 13-year period has helped in the understanding of the stable isotopic speleothem content and inthe hydrology. For example, it was demonstrated that most of the calcite CaCO3 carbon comes from the soil CO2, which explainsthe sensitivity of the δ13C to any vegetation and climatic changes. Drip rate monitoring, carried out under four stalactites from thelower and upper galleries, has shown a well marked seasonality of the seepage water with high flow rates during winter and spring.A time delay of about two months is observed between the water excess (estimated from outside meteorological stations and thedrip rate in the cave. A great heterogeneity in the flow rate amplitude variations and in the annual quantity of water between twonearby stalactites is observed, confirming the complexity of the micro-fissure network system in the unsaturated zone. At a dailyscale, the air pressure and drip rates are anti-correlated probably because of pressure stress on the fissure network. Cave air CO2concentration follows soil CO2 production and is correlated with its δ13C content. Since the beginning of the monitoring, the cave airtemperature, in both lower and upper galleries, displays a warming trend of ~+0.4°C±0.1/10yrs. This might be the consequence ofthe outside temperature increase that reaches the Villars Cave galleries through thermal wave conduction. Chemistry monitoringover a few years has shown that the seepage water of the lower gallery stations is significantly more concentrated in trace and minorelements (i.e. Sr, Mg, Ba, U than the upper stations, probably due to the 10-20 m depth difference between these galleries, whichimplies a different seepage pathway

  7. Mapping planetary caves with an autonomous, heterogeneous robot team

    Science.gov (United States)

    Husain, Ammar; Jones, Heather; Kannan, Balajee; Wong, Uland; Pimentel, Tiago; Tang, Sarah; Daftry, Shreyansh; Huber, Steven; Whittaker, William L.

    Caves on other planetary bodies offer sheltered habitat for future human explorers and numerous clues to a planet's past for scientists. While recent orbital imagery provides exciting new details about cave entrances on the Moon and Mars, the interiors of these caves are still unknown and not observable from orbit. Multi-robot teams offer unique solutions for exploration and modeling subsurface voids during precursor missions. Robot teams that are diverse in terms of size, mobility, sensing, and capability can provide great advantages, but this diversity, coupled with inherently distinct low-level behavior architectures, makes coordination a challenge. This paper presents a framework that consists of an autonomous frontier and capability-based task generator, a distributed market-based strategy for coordinating and allocating tasks to the different team members, and a communication paradigm for seamless interaction between the different robots in the system. Robots have different sensors, (in the representative robot team used for testing: 2D mapping sensors, 3D modeling sensors, or no exteroceptive sensors), and varying levels of mobility. Tasks are generated to explore, model, and take science samples. Based on an individual robot's capability and associated cost for executing a generated task, a robot is autonomously selected for task execution. The robots create coarse online maps and store collected data for high resolution offline modeling. The coordination approach has been field tested at a mock cave site with highly-unstructured natural terrain, as well as an outdoor patio area. Initial results are promising for applicability of the proposed multi-robot framework to exploration and modeling of planetary caves.

  8. Reproductive Seasonality in Nesticus (Araneae: Nesticidae) Cave Spiders.

    Science.gov (United States)

    Carver, Linnea M; Perlaky, Patricia; Cressler, Alan; Zigler, Kirk S

    2016-01-01

    Spiders of the family Nesticidae are members of cave communities around the world with cave-obligate (troglobiotic) species known from North America, Europe, Asia and the Indo-Pacific. A radiation of Nesticus (Araneae: Nesticidae) in the southern Appalachians includes ten troglobiotic species. Many of these species are of conservation interest due to their small ranges, with four species being single-cave endemics. Despite conservation concerns and their important role as predators in cave communities, we know little about reproduction and feeding in this group. We addressed this knowledge gap by examining populations of two species on a monthly basis for one year. We made further observations on several other species and populations, totaling 671 individual spider observations. This more than doubled the reported observations of reproduction and feeding in troglobiotic Nesticus. Female Nesticus carry egg sacs, facilitating the determination of the timing and frequency of reproduction. We found that Nesticus exhibit reproductive seasonality. Females carried egg sacs from May through October, with a peak in frequency in June. These spiders were rarely observed with prey; only 3.3% (22/671) of individuals were observed with prey items. The frequency at which prey items were observed did not vary by season. Common prey items were flies, beetles and millipedes. Troglobiotic species constituted approximately half of all prey items observed. This result represents a greater proportion of troglobiotic prey than has been reported for various troglophilic spiders. Although our findings shed light on the life history of troglobiotic Nesticus and on their role in cave ecosystems, further work is necessary to support effective conservation planning for many of these rare species.

  9. Speleogenesis, geometry, and topology of caves: A quantitative study of 3D karst conduits

    Science.gov (United States)

    Jouves, Johan; Viseur, Sophie; Arfib, Bruno; Baudement, Cécile; Camus, Hubert; Collon, Pauline; Guglielmi, Yves

    2017-12-01

    Karst systems are hierarchically spatially organized three-dimensional (3D) networks of conduits behaving as drains for groundwater flow. Recently, geostatistical approaches proposed to generate karst networks from data and parameters stemming from analogous observed karst features. Other studies have qualitatively highlighted relationships between speleogenetic processes and cave patterns. However, few studies have been performed to quantitatively define these relationships. This paper reports a quantitative study of cave geometries and topologies that takes the underlying speleogenetic processes into account. In order to study the spatial organization of caves, a 3D numerical database was built from 26 caves, corresponding to 621 km of cumulative cave passages representative of the variety of karst network patterns. The database includes 3D speleological surveys for which the speleogenetic context is known, allowing the polygenic karst networks to be divided into 48 monogenic cave samples and classified into four cave patterns: vadose branchwork (VB), water-table cave (WTC), looping cave (LC), and angular maze (AM). Eight morphometric cave descriptors were calculated, four geometrical parameters (width-height ratio, tortuosity, curvature, and vertical index) and four topological ones (degree of node connectivity, α and γ graph indices, and ramification index) respectively. The results were validated by statistical analyses (Kruskal-Wallis test and PCA). The VB patterns are clearly distinct from AM ones and from a third group including WTC and LC. A quantitative database of cave morphology characteristics is provided, depending on their speleogenetic processes. These characteristics can be used to constrain and/or validate 3D geostatistical simulations. This study shows how important it is to relate the geometry and connectivity of cave networks to recharge and flow processes. Conversely, the approach developed here provides proxies to estimate the evolution of

  10. Reconciling Mining with the Conservation of Cave Biodiversity: A Quantitative Baseline to Help Establish Conservation Priorities.

    Science.gov (United States)

    Jaffé, Rodolfo; Prous, Xavier; Zampaulo, Robson; Giannini, Tereza C; Imperatriz-Fonseca, Vera L; Maurity, Clóvis; Oliveira, Guilherme; Brandi, Iuri V; Siqueira, José O

    2016-01-01

    Caves pose significant challenges for mining projects, since they harbor many endemic and threatened species, and must therefore be protected. Recent discussions between academia, environmental protection agencies, and industry partners, have highlighted problems with the current Brazilian legislation for the protection of caves. While the licensing process is long, complex and cumbersome, the criteria used to assign caves into conservation relevance categories are often subjective, with relevance being mainly determined by the presence of obligate cave dwellers (troglobites) and their presumed rarity. However, the rarity of these troglobitic species is questionable, as most remain unidentified to the species level and their habitats and distribution ranges are poorly known. Using data from 844 iron caves retrieved from different speleology reports for the Carajás region (South-Eastern Amazon, Brazil), one of the world's largest deposits of high-grade iron ore, we assess the influence of different cave characteristics on four biodiversity proxies (species richness, presence of troglobites, presence of rare troglobites, and presence of resident bat populations). We then examine how the current relevance classification scheme ranks caves with different biodiversity indicators. Large caves were found to be important reservoirs of biodiversity, so they should be prioritized in conservation programs. Our results also reveal spatial autocorrelation in all the biodiversity proxies assessed, indicating that iron caves should be treated as components of a cave network immersed in the karst landscape. Finally, we show that by prioritizing the conservation of rare troglobites, the current relevance classification scheme is undermining overall cave biodiversity and leaving ecologically important caves unprotected. We argue that conservation efforts should target subterranean habitats as a whole and propose an alternative relevance ranking scheme, which could help simplify the

  11. Seasonal Temperature Variations controlling Cave Ventilation Processes in Cueva Larga, Puerto Rico

    Science.gov (United States)

    Winter, A.; Vieten, R.; Warken, S. F.; Schrӧder-Ritzrau, A.; Miller, T. E.; Scholz, D.

    2016-12-01

    Two years of monthly monitoring result in much better understanding of ventilation processes in caves. Cueva Larga, a tropical cave in Puerto Rico is 1440 m long with a large main passage (about 116,000 m3). Cave air pCO2 in the main passage varied seasonally, between 600 ppm in winter and 1800 ppm in summer. The seasonal variability in cave pCO2 made it possible to estimate a cave air exchange time of 36±5 days and a winter ventilation rate of 3,200±800 m3/day for the main cave passage. Calculations of virtual temperature and differences between cave and surface temperature show that the seasonal temperature cycle is the main driver of the alternation between a well-ventilated winter mode and a near-stagnant summer mode. The winter mode is characterized by a positive buoyancy contrast at night leading to maximal cave ventilation, while during summer ventilation is at a minimum. Between winter and summer, a transitional mode of partial cave ventilation is observed. On shorter time scales (diurnal to weekly), cave pCO2 is also influenced by atmospheric pressure but this variation is one order of magnitude lower than the seasonal pCO2 change. The cave morphology of Cueva Larga including its large volume, tubular shape and the obstructed cave entrance geometry are important boundary conditions for the observed ventilation patterns. Our findings emphasize that cave systems with varying morphology have to be studied individually in order to correctly describe ventilation processes.

  12. Ancient lineage, young troglobites: recent colonization of caves by Nesticella spiders.

    Science.gov (United States)

    Zhang, Yuanyuan; Li, Shuqiang

    2013-09-04

    The evolution and origin of cave organisms is a recurring issue in evolutionary studies, but analyses are often hindered by the inaccessibility of caves, morphological convergence, and complex colonization processes. Here we investigated the evolutionary history of Nesticella cave spiders, which are mainly distributed in the Yunnan-Guizhou Plateau, China. With comprehensive sampling and phylogenetic and coalescent-based analyses, we investigated the tempo and mode of diversification and the origins of these troglobites. We also aimed to determine which factors have influenced the diversification of this little-known group. Coalescent-based species delimitation validated the 18 species recognized by morphological inspection and also suggested the existence of cryptic lineages. Divergence time estimates suggested that Nesticella cave spiders in the Yunnan-Guizhou Plateau constituted a monophyletic troglobite clade that originated in the middle Miocene (11.1-18.6 Ma). Although the Yunnan-Guizhou Plateau clade was composed exclusively of troglobite species, suggesting an ancient common subterranean ancestor, we favor multiple, independent cave colonizations during the Pleistocene over a single ancient cave colonization event to explain the origin of these cave faunas. The diversification of plateau Nesticella has been greatly influenced by the sequential uplift of the plateau and likely reflects multiple cave colonizations over time by epigean ancestors during Pleistocene glacial advances. We concluded that plateau cave Nesticella represent an ancient group of spiders, but with young troglobite lineages that invaded caves only recently. The absence of extant epigean relatives and nearly complete isolation among caves supported their relict status. Our work highlights the importance of comprehensive sampling for studies of subterranean diversity and the evolution of cave organisms. The existence of potentially cryptic species and the relict status of Nesticella

  13. Sources of sulphate minerals in limestone cave-a possible evidence of anthropogenic activity: a case study in Črna Jama Cave (Slovenia).

    Science.gov (United States)

    Jarc, Simona; Miler, Miloš; Šebela, Stanka; Zupančič, Nina

    2017-12-01

    In the caves, the formation of cave minerals is a consequence of a variety of chemical reactions, some of them also due to human activity. There are many caves in Slovenia, but sulphate minerals are not very often reported and analysed. In this study, the presence of sulphate minerals is detected by SEM/EDS analysis of speleothems from Črna Jama, a cave near Kočevje (southern Slovenia). The cave is characterised by its dark, almost black colour on cave walls, floor and speleothems. Anthropogenic influence in the cave is still visible, including the remains of a fireplace, some inscriptions on the walls and wooden containers. The analyses of some of the black-coated speleothems reveal the presence of calcium sulphate, confirmed by XRD as gypsum. Gypsum crystals are around 50 μm in size, and they occur in thin crusts. Additionally, some rare authigenic baryte crystals a few micrometres in size are detected. The sulphates δ 34 S value in gypsum found on dark coloured speleothems is + 10.4‰ Vienna Canyon Diablo Troilite (VCDT), while the sulphate δ 34 S of the bedrock is + 8.6‰ VCDT. The more likely source of sulphate ions is thus biomass burning rather than bedrock. Also, bedrock and biomass ash are a very probable source of calcium and barium. The highly probable pyrogenous origin of sulphates draws attention to human impact on cave mineralogy.

  14. Mitochondrial DNA from El Mirador cave (Atapuerca, Spain reveals the heterogeneity of Chalcolithic populations.

    Directory of Open Access Journals (Sweden)

    Daniel Gómez-Sánchez

    Full Text Available Previous mitochondrial DNA analyses on ancient European remains have suggested that the current distribution of haplogroup H was modeled by the expansion of the Bell Beaker culture (ca 4,500-4,050 years BP out of Iberia during the Chalcolithic period. However, little is known on the genetic composition of contemporaneous Iberian populations that do not carry the archaeological tool kit defining this culture. Here we have retrieved mitochondrial DNA (mtDNA sequences from 19 individuals from a Chalcolithic sample from El Mirador cave in Spain, dated to 4,760-4,200 years BP and we have analyzed the haplogroup composition in the context of modern and ancient populations. Regarding extant African, Asian and European populations, El Mirador shows affinities with Near Eastern groups. In different analyses with other ancient samples, El Mirador clusters with Middle and Late Neolithic populations from Germany, belonging to the Rössen, the Salzmünde and the Baalberge archaeological cultures but not with contemporaneous Bell Beakers. Our analyses support the existence of a common genetic signal between Western and Central Europe during the Middle and Late Neolithic and points to a heterogeneous genetic landscape among Chalcolithic groups.

  15. Polar bears, Ursus maritimus

    Science.gov (United States)

    Rode, Karyn D.; Stirling, Ian

    2017-01-01

    Polar bears are the largest of the eight species of bears found worldwide and are covered in a pigment-free fur giving them the appearance of being white. They are the most carnivorous of bear species consuming a high-fat diet, primarily of ice-associated seals and other marine mammals. They range throughout the circumpolar Arctic to the southernmost extent of seasonal pack ice.

  16. Determination of the Radon Concentration and Radioactivity Level in Karaca Cave

    International Nuclear Information System (INIS)

    Kara, A.

    2008-01-01

    In this study, the radon gas concentration in the Karaca cave which is open to tourism has been determined and the negative effects of radon gas on people were discussed. Karaca cave (Gumushane) is visited by many tourists every year. The measurements of radon gas concentration which affects the health of human beings negatively and even causes the lung cancer when it reaches high points have been done for the summer and winter season. LR-115 passive radon detector was used to determine radon concentrations in the cave both winter and summer season. The average radon concentration in the Karaca cave were determined as 823 Bq/m 3 and 1023 Bq/m 3 for the summer and winter season, respectively. Moreover, to find out the natural radioactivity in the cave, the gamma spectroscopic analysis of soil, stone and stalagmite samples were carried out and their relations with the radon gas in the cave atmosphere was analyzed

  17. Mediterranean Recluse Spider, Loxosceles rufescens (Araneae: Sicariidae from Charkhab Cave, Southern Iran

    Directory of Open Access Journals (Sweden)

    Saber Sadeghi

    2017-04-01

    Full Text Available Background: The best-known dangerous spiders belong to the six genera. The genus Loxosceles or violin spiders are well known for their ability to cause skin necrosis or loxoscelism. All Loxosceles species have medical im­portance due to their necrotizing venom. The present article reports the occurrence of L. rufescens in Charkhab Cave, south of Iran (Larestan.Methods: The specimens were collected from the Charkhab Cave using handling forceps, paintbrush and aspirator and preserved in 96% ethanol.Results: Loxosceles rufescens, a medically important spider, is recorded from Charkhab Cave in Fars Province (southwest of Iran. Identification of L. rufescens was performed based on external morphology and the features of male genitalia.Conclusion: Presence of L. rufescens in south of Iran especially in a cave confirmed that this species is a widely distributed species in Iran. Therefore, cavers or cave visitors should be aware of this poisonous spider in caves.

  18. Geophysical exploration in vicinity of the Unicorn Cave, South Harz Mountains, Germany

    Science.gov (United States)

    Kaufmann, Georg; Romanov, Douchko; Nielbock, Ralf

    2010-05-01

    The Unicorn Cave in the southern Harz Mountains in Germany is located in an outcrop of dolomite from the Zechstein formation, which is underlain by Grauwacke rocks. The cave, about 600 meters long, consists of several large chambers, which are connected by a gallery following the main fault alignments in E/W, NE/SW, and NW/SE direction. The overburden of the cave is shallow, between 10 and 30 m. We have used this cave site to perform a sensitivity test for both gravimetric and geoelectic methods above the cave. Additionally, geoelectic mapping has been used to assess the thickness of the cave sediments in one of the chambers. Our results show a clear signal in the Bouguer anomaly, which can only be explained by a combined model of the void space and the sediment filling. Geoelectric results are less clear, but support the gravimetry.

  19. Evolution and adaptation of marine annelids in interstitial and cave habitats

    DEFF Research Database (Denmark)

    Martinez Garcia, Alejandro

    relatives in cave subterranean ecological refugia. Active colonization and ecological speciation to particular cave niches has been alternatively suggested, but the evaluation of that scenario is obscured by the dominance of crustaceans in anchialine habitats, ecologically similar out and inside caves....... The main goal of this thesis is to explore the evolutionary processes behind colonization and adaptation to submarine cave ecosystems in the Atlantic Ocean using annelids as a model, mainly when they involved ancestrally interstitial forms. In order to do that, we studied selected lineages of annelids...... with cave and interstitial representatives, mainly the families Protodrilidae, Nerillidae, Saccocirridae and Scalibregmatidae. The studies combined the characterization of ancestral and cave habitats, with morphological investigations and phylogenetic analyses founded on extensive taxon coverage...

  20. Measurements of seasonal and daily radon daughter concentration fluctuations in National Park Service caves

    International Nuclear Information System (INIS)

    Yarborough, K.A.

    1977-01-01

    The National Park Service (NPS) is studying levels of airborne alpha radiation from radon and thoron in all NPS administered caves in which tours for visitors are regularly conducted. The NPS research has the dual but complementary objectives of safeguarding health at the NPS administered caves, and to develop data on alpha radiation levels and on natural airflows in NPS caves. The results reported here for NPS caves describe concepts hypothesized for the objectives. In addition the data can be used by various agencies to clarify health standards for exposures to low airborne alpha radiation levels in cave environments. These results show daily and seasonal trends and the influence of natural ventilation by air circulation for each cave investigated

  1. Hollow volcanic tumulus caves of Kilauea Caldera, Hawaii County, Hawaii

    Directory of Open Access Journals (Sweden)

    William R. Halliday

    1998-01-01

    Full Text Available In addition to lava tube caves with commonly noted features, sizable subcrustal spaces of several types exist on the floor of Kilauea Caldera. Most of these are formed by drainage of partially stabilized volcanic structures enlarged or formed by injection of very fluid lava beneath a plastic crust. Most conspicuous are hollow tumuli, possibly first described by Walker in 1991. Walker mapped and described the outer chamber of Tumulus E-I Cave. Further exploration has revealed that it has a hyperthermic inner room beneath an adjoining tumulus with no connection evident on the surface. Two lengthy, sinuous hollow tumuli also are present in this part of the caldera. These findings support Walkers conclusions that hollow tumuli provide valuable insights into tumulus-forming mechanisms, and provide information about the processes of emplacement of pahoehoe sheet flows.

  2. A diverse intrinsic antibiotic resistome from a cave bacterium.

    Science.gov (United States)

    Pawlowski, Andrew C; Wang, Wenliang; Koteva, Kalinka; Barton, Hazel A; McArthur, Andrew G; Wright, Gerard D

    2016-12-08

    Antibiotic resistance is ancient and widespread in environmental bacteria. These are therefore reservoirs of resistance elements and reflective of the natural history of antibiotics and resistance. In a previous study, we discovered that multi-drug resistance is common in bacteria isolated from Lechuguilla Cave, an underground ecosystem that has been isolated from the surface for over 4 Myr. Here we use whole-genome sequencing, functional genomics and biochemical assays to reveal the intrinsic resistome of Paenibacillus sp. LC231, a cave bacterial isolate that is resistant to most clinically used antibiotics. We systematically link resistance phenotype to genotype and in doing so, identify 18 chromosomal resistance elements, including five determinants without characterized homologues and three mechanisms not previously shown to be involved in antibiotic resistance. A resistome comparison across related surface Paenibacillus affirms the conservation of resistance over millions of years and establishes the longevity of these genes in this genus.

  3. Exposure to radon in caves and abandoned mines

    International Nuclear Information System (INIS)

    Dixon, D.W.

    1996-01-01

    The significance for health of exposure to radon daughters during leisure excursions in discussed mines or caves is considered for visitors with interests in speleology, mineral collecting, mining history and youth training. General members of the public might also enter tunnels. Potential annual exposures based on radon measurements in various mines and caves are estimated and it is concluded that the annual exposure of individuals who undertake frequent and prolonged trips to underground systems might exceed 10 6 Bq h m -3 . Exposures to general members of the public are likely to be much lower. The National Radiological Protection Board has developed proposals for a coherent and comprehensive scheme to promote dose limitation in a wide range of circumstances. These are described, with current initiatives on consultation with National Associations, local Government and many special interest groups. (author)

  4. Decommissioning of fuel PIE caves at Berkeley Nuclear Laboratories

    International Nuclear Information System (INIS)

    Brant, A.W.

    1990-01-01

    This paper describes the first major contract awarded to private industry to carry out decommissioning of a facility with significant radiation levels. The work required operatives to work in pressurised suits, entry times were significantly affected by sources of radiation in the Caves, being as low as thirty minutes per day initially. The Caves at Berkeley Nuclear Laboratories carry out post irradiation examination of fuel elements support units and reactor core components from CEGB power stations. The decommissioning work is part of an overall refurbishment of the facility to allow the receipt of AGR Fuel Stringer Component direct from power stations. The paper describes the decommissioning and decontamination of the facility from the remote removal and clean up work carried out by the client to the hands-on work. It includes reference to entry times, work patterns, interfaces with the client and the operations of the laboratory. Details of a specially adapted size reduction method are given. (Author)

  5. Ancient mitochondrial DNA reveals convergent evolution of giant short-faced bears (Tremarctinae) in North and South America.

    Science.gov (United States)

    Mitchell, Kieren J; Bray, Sarah C; Bover, Pere; Soibelzon, Leopoldo; Schubert, Blaine W; Prevosti, Francisco; Prieto, Alfredo; Martin, Fabiana; Austin, Jeremy J; Cooper, Alan

    2016-04-01

    The Tremarctinae are a subfamily of bears endemic to the New World, including two of the largest terrestrial mammalian carnivores that have ever lived: the giant, short-faced bears Arctodus simus from North America and Arctotherium angustidens from South America (greater than or equal to 1000 kg). Arctotherium angustidens became extinct during the Early Pleistocene, whereas Arctodus simus went extinct at the very end of the Pleistocene. The only living tremarctine is the spectacled bear (Tremarctos ornatus), a largely herbivorous bear that is today only found in South America. The relationships among the spectacled bears (Tremarctos), South American short-faced bears (Arctotherium) and North American short-faced bears (Arctodus) remain uncertain. In this study, we sequenced a mitochondrial genome from an Arctotherium femur preserved in a Chilean cave. Our molecular phylogenetic analyses revealed that the South American short-faced bears were more closely related to the extant South American spectacled bear than to the North American short-faced bears. This result suggests striking convergent evolution of giant forms in the two groups of short-faced bears (Arctodus and Arctotherium), potentially as an adaptation to dominate competition for megafaunal carcasses. © 2016 The Author(s).

  6. EcoBears

    DEFF Research Database (Denmark)

    Nielsen, Nick; Pedersen, Sandra Bleuenn; Sørensen, Jens Ager

    2015-01-01

    In this paper, we introduce the EcoBears concept that aims to augment household appliances with functional and aesthetic features to promote their "use'' and "longevity of use'' to prevent their disposal. The EcoBears also aim to support the communication of environmental issues in the home setting....... We present our initial design and implementation of the EcoBears that consist of two bear modules (a mother and her cub). We also present our preliminary concept validations and lessons learned to be considered for future directions....

  7. Bearing restoration by grinding

    Science.gov (United States)

    Hanau, H.; Parker, R. J.; Zaretsky, E. V.; Chen, S. M.; Bull, H. L.

    1976-01-01

    A joint program was undertaken by the NASA Lewis Research Center and the Army Aviation Systems Command to restore by grinding those rolling-element bearings which are currently being discarded at aircraft engine and transmission overhaul. Three bearing types were selected from the UH-1 helicopter engine (T-53) and transmission for the pilot program. No bearing failures occurred related to the restoration by grinding process. The risk and cost of a bearing restoration by grinding programs was analyzed. A microeconomic impact analysis was performed.

  8. Polar bears at risk

    Energy Technology Data Exchange (ETDEWEB)

    Norris, S.; Rosentrater, L.; Eid, P.M. [WWF International Arctic Programme, Oslo (Norway)

    2002-05-01

    Polar bears, the world's largest terrestrial carnivore, spend much of their lives on the arctic sea ice. This is where they hunt and move between feeding, denning, and resting areas. The world population, estimated at 22,000 bears, is made up of 20 relatively distinct populations varying in size from a few hundred to a few thousand animals. About 60 per cent of all polar bears are found in Canada. In general, the status of this species is stable, although there are pronounced differences between populations. Reductions in the extent and thickness of sea ice has lead the IUCN Polar Bear Specialist Group to describe climate change as one of the major threats facing polar bears today. Though the long-term effects of climate change will vary in different areas of the Arctic, impacts on the condition and reproductive success of polar bears and their prey are likely to be negative. Longer ice-free periods resulting from earlier break-up of sea ice in the spring and later formation in the fall is already impacting polar bears in the southern portions of their range. In Canada's Hudson Bay, for example, bears hunt on the ice through the winter and into early summer, after which the ice melts completely, forcing bears ashore to fast on stored fat until freeze-up in the fall. The time bears have on the ice to hunt and build up their body condition is cut short when the ice melts early. Studies from Hudson Bay show that for every week earlier that ice break-up occurs, bears will come ashore 10 kg lighter and in poorer condition. It is likely that populations of polar bears dividing their time between land and sea will be severely reduced and local extinctions may occur as greenhouse gas emissions continue to rise and sea ice melts. Expected changes in regional weather patterns will also impact polar bears. Rain in the late winter can cause maternity dens to collapse before females and cubs have departed, thus exposing occupants to the elements and to predators. Such

  9. Asymmetric Meckel Cave Enlargement: A Potential Marker of PHACES Syndrome.

    Science.gov (United States)

    Wright, J N; Wycoco, V

    2017-06-01

    PHACES syndrome is a complex of morphologic abnormalities of unknown cause and includes posterior fossa abnormalities; head and neck infantile hemangiomas; arterial, cardiac, and eye anomalies; and sternal or abdominal wall defects. Accurate identification of the syndrome is important for optimal treatment. The purpose of this study was to investigate the incidence of asymmetric Meckel cave enlargement, a potential novel imaging marker, in a population of patients referred for evaluation of possible PHACES syndrome. Eighty-five patients referred for neuroimaging evaluation of possible PHACES syndrome were identified and stratified on the basis of their ultimate clinical PHACES diagnosis categorization into PHACES, possible PHACES, or not PHACES. MR imaging studies were subsequently reviewed for the presence or absence of unilateral Meckel cave enlargement, with the reviewer blinded to the ultimate PHACES syndrome categorization. Twenty-five of 85 patients (29%) were ultimately categorized as having PHACES or possible PHACES according to consensus guidelines. Asymmetric Meckel cave enlargement was present in 76% (19/25) of these patients and in 82% (19/23) of only those patients with definite PHACES. This finding was present in none of the 60 patients determined not to have PHACES syndrome. In 7/19 patients (37%) with this finding, subtle MR imaging abnormalities consistent with PHACES were missed on the initial MR imaging interpretation. Asymmetric Meckel cave enlargement was a common feature of patients with PHACES in our cohort and may serve as a novel imaging marker. Increased awareness of this imaging feature has the potential to increase the diagnostic accuracy of PHACES. © 2017 by American Journal of Neuroradiology.

  10. Post-speleogenetic biogenic modification of Gomantong Caves, Sabah, Borneo

    Science.gov (United States)

    Lundberg, Joyce; McFarlane, Donald A.

    2012-07-01

    The Gomantong cave system of eastern Sabah, Malaysia, is well-known as an important site for harvesting edible bird-nests and, more recently, as a tourist attraction. Although the biology of the Gomantong system has been repeatedly studied, very little attention has been given to the geomorphology. Here, we report on the impact of geobiological modification in the development of the modern aspect of the cave, an important but little recognized feature of tropical caves. Basic modeling of the metabolic outputs from bats and birds (CO2, H2O, heat) reveals that post-speleogenetic biogenic corrosion can erode bedrock by between ~ 3.0 mm/ka (1 m/~300 ka) and ~ 4.6 mm/ka (1 m/~200 ka). Modeling at high densities of bats yields rates of corrosion of ~ 34 mm/ka (or 1 m/~30 ka). Sub-aerial corrosion creates a previously undescribed speleological feature, the apse-flute, which is semicircular in cross-section and ~ 80 cm wide. It is vertical regardless of rock properties, developing in parallel but apparently completely independently, and often unbroken from roof to floor. They end at a blind hemi-spherical top with no extraneous water source. Half-dome ceiling conch pockets are remnants of previous apse-fluting. Sub-cutaneous corrosion creates the floor-level guano notch formed by organic acid dissolution of bedrock in contact with guano. Speleogenetic assessment suggests that as much as 70-95% of the total volume of the modern cave may have been opened by direct subaerial biogenic dissolution and biogenically-induced collapse, and by sub-cutaneous removal of limestone, over a timescale of 1-2 Ma.

  11. Reconstruction of bomb 14C time history recorded in the stalagmite from Postojna Cave

    International Nuclear Information System (INIS)

    Vokal, B.; Genty, D.; Obelic, B.

    2002-01-01

    The karstic caves provide valuable resources for reconstruction of environmental conditions on the continent in the past. This is possible due to the great stability of climatic conditions within a cave. Secondary minerals deposited in caves, known as speleothems, preserve records of long-term climatic and environmental changes at the site of their deposition and in the vicinity. The purity of speleothems and their chemical and physical stability make them exceptionally well suited for detailed geochemical and isotopic analysis

  12. Insectivorous bat reproduction and human cave visitation in Cambodia: A perfect conservation storm?

    Science.gov (United States)

    Cappelle, Julien; Hoem, Thavry

    2018-01-01

    Cave roosting bats represent an important component of Southeast Asian bat diversity and are vulnerable to human disturbance during critical reproductive periods (pregnancy, lactation and weaning). Because dramatic growth of cave tourism in recent decades has raised concerns about impacts on cave bats in the region, we assessed the reproductive phenology of two insectivorous species (Hipposideros larvatus sensu lato and Taphozous melanopogon) at three caves in Cambodia for 23 months in 2014–2016 and evaluated human visitation to these sites between 2007 and 2014. Despite the differing foraging strategies employed by the two taxa, the temporal consistency observed in proportions of pregnant, lactating and juvenile bats indicates that their major birth peaks coincide with the time of greatest cave visitation annually, particularly for domestic visitors and namely during the Cambodian new year in April. They also reflect rainfall patterns and correspond with the reproductive phenology of insectivorous cave bats in Vietnam. These findings were predictable because 1) insect biomass and thus food availability for insectivorous bats are optimal for ensuring survival of young following this period, and 2) the Khmer new year is the most significant month for religious ceremonies and thus domestic cave visitation nationally, due to the abundance of Buddhist shrines and temples in Cambodian caves. While the impact of visitor disturbance on bat population recruitment cannot be empirically assessed due to lack of historical data, it is nonetheless likely to have been considerable and raises a conservation concern. Further, because growing evidence suggests that insectivorous cave bats exhibit reproductive synchrony across continental Southeast Asia where countless cave shrines are heavily frequented during April in Theravada Buddhist countries (e.g., Myanmar, Thailand, Cambodia and Laos), our results may have wider applicability in the region. We consequently advocate for

  13. Technical devices of powered roof support for the top coal caving as automation objects

    Science.gov (United States)

    Nikitenko, M. S.; Kizilov, S. A.; Nikolaev, P. I.; Kuznetsov, I. S.

    2018-05-01

    In the paper technical devices for the top coal caving as automation objects in the composition of the longwall mining complex (LTCC) are considered. The proposed concept for automation of the top coal caving process allows caving efficiency to be ensured, coal dilution to be prevented, conveyor overloading to be prevented, the shearer service personnel to be unloaded, the influence of the “human factor” to be reduced.

  14. Insectivorous bat reproduction and human cave visitation in Cambodia: A perfect conservation storm?

    Science.gov (United States)

    Lim, Thona; Cappelle, Julien; Hoem, Thavry; Furey, Neil

    2018-01-01

    Cave roosting bats represent an important component of Southeast Asian bat diversity and are vulnerable to human disturbance during critical reproductive periods (pregnancy, lactation and weaning). Because dramatic growth of cave tourism in recent decades has raised concerns about impacts on cave bats in the region, we assessed the reproductive phenology of two insectivorous species (Hipposideros larvatus sensu lato and Taphozous melanopogon) at three caves in Cambodia for 23 months in 2014-2016 and evaluated human visitation to these sites between 2007 and 2014. Despite the differing foraging strategies employed by the two taxa, the temporal consistency observed in proportions of pregnant, lactating and juvenile bats indicates that their major birth peaks coincide with the time of greatest cave visitation annually, particularly for domestic visitors and namely during the Cambodian new year in April. They also reflect rainfall patterns and correspond with the reproductive phenology of insectivorous cave bats in Vietnam. These findings were predictable because 1) insect biomass and thus food availability for insectivorous bats are optimal for ensuring survival of young following this period, and 2) the Khmer new year is the most significant month for religious ceremonies and thus domestic cave visitation nationally, due to the abundance of Buddhist shrines and temples in Cambodian caves. While the impact of visitor disturbance on bat population recruitment cannot be empirically assessed due to lack of historical data, it is nonetheless likely to have been considerable and raises a conservation concern. Further, because growing evidence suggests that insectivorous cave bats exhibit reproductive synchrony across continental Southeast Asia where countless cave shrines are heavily frequented during April in Theravada Buddhist countries (e.g., Myanmar, Thailand, Cambodia and Laos), our results may have wider applicability in the region. We consequently advocate for

  15. Insectivorous bat reproduction and human cave visitation in Cambodia: A perfect conservation storm?

    Directory of Open Access Journals (Sweden)

    Thona Lim

    Full Text Available Cave roosting bats represent an important component of Southeast Asian bat diversity and are vulnerable to human disturbance during critical reproductive periods (pregnancy, lactation and weaning. Because dramatic growth of cave tourism in recent decades has raised concerns about impacts on cave bats in the region, we assessed the reproductive phenology of two insectivorous species (Hipposideros larvatus sensu lato and Taphozous melanopogon at three caves in Cambodia for 23 months in 2014-2016 and evaluated human visitation to these sites between 2007 and 2014. Despite the differing foraging strategies employed by the two taxa, the temporal consistency observed in proportions of pregnant, lactating and juvenile bats indicates that their major birth peaks coincide with the time of greatest cave visitation annually, particularly for domestic visitors and namely during the Cambodian new year in April. They also reflect rainfall patterns and correspond with the reproductive phenology of insectivorous cave bats in Vietnam. These findings were predictable because 1 insect biomass and thus food availability for insectivorous bats are optimal for ensuring survival of young following this period, and 2 the Khmer new year is the most significant month for religious ceremonies and thus domestic cave visitation nationally, due to the abundance of Buddhist shrines and temples in Cambodian caves. While the impact of visitor disturbance on bat population recruitment cannot be empirically assessed due to lack of historical data, it is nonetheless likely to have been considerable and raises a conservation concern. Further, because growing evidence suggests that insectivorous cave bats exhibit reproductive synchrony across continental Southeast Asia where countless cave shrines are heavily frequented during April in Theravada Buddhist countries (e.g., Myanmar, Thailand, Cambodia and Laos, our results may have wider applicability in the region. We consequently

  16. Direct measurement of present-day tectonic movement and associated radon flux in Postojna Cave, Slovenia

    Czech Academy of Sciences Publication Activity Database

    Šebela, S.; Vaupotič, J.; Košťák, Blahoslav; Stemberk, Josef

    2010-01-01

    Roč. 72, č. 1 (2010), s. 21-34 ISSN 1090-6924 R&D Projects: GA ČR GA205/09/2024; GA MŠk MEB091005 Institutional research plan: CEZ:AV0Z30460519 Keywords : fault displacements * radon flux * Postojna Cave Subject RIV: DB - Geology ; Mineralogy Impact factor: 0.842, year: 2010 www.caves.org/pub/journal/Journal_of_Cave_and_Karst_Studies_volume_72.htm

  17. Investigation of Sediment Pathways and Concealed Sedimentological Features in Hidden River Cave, Kentucky

    Science.gov (United States)

    Feist, S.; Maclachlan, J. C.; Reinhardt, E. G.; McNeill-Jewer, C.; Eyles, C.

    2016-12-01

    Hidden River Cave is part of a cave system hydrogeologically related to Mammoth Cave in Kentucky and is a multi-level active cave system with 25km of mapped passages. Upper levels experience flow during flood events and lower levels have continuously flowing water. Improper industrial and domestic waste disposal and poor understanding of local hydrogeology lead to contamination of Hidden River Cave in the early 1940s. Previously used for hydroelectric power generation and as a source of potable water the cave was closed to the public for almost 50 years. A new sewage treatment plant and remediation efforts since 1989 have improved the cave system's health. This project focuses on sedimentological studies in the Hidden River Cave system. Water and sediment transport in the cave are being investigated using sediment cores, surface sediment samples and water level data. An Itrax core scanner is used to analyze sediment cores for elemental concentrations, magnetic susceptibility, radiography, and high resolution photography. Horizons of metal concentrations in the core allow correlation of sedimentation events in the cave system. Thecamoebian (testate amoebae) microfossils identified in surface samples allow for further constraint of sediment sources, sedimentation rates, and paleoclimatic analysis. Dive recorders monitor water levels, providing data to further understand the movement of sediment through the cave system. A general time constraint on the sediment's age is based on the presence of microplastic in the surface samples and sediment cores, and data from radiocarbon and lead-210 dating. The integration of various sedimentological data allows for better understanding of sedimentation processes and their record of paleoenvironmental change in the cave system. Sediment studies and methodologies from this project can be applied to other karst systems, and have important applications for communities living on karst landscapes and their water management policies.

  18. A cave population of Isbrueckerichthys alipionis (Gosline, 1947 in the Upper Ribeira karst area, southeastern Brazil (Siluriformes: Loricariidae

    Directory of Open Access Journals (Sweden)

    Eleonora Trajano

    Full Text Available A cave population of the armored catfish Isbrueckerichthys alipionis is reported from the Santana Cave, in the rio Betari watershed, Upper Ribeira karst area, Iporanga, São Paulo State, southeastern Brazil. The cave population was compared to an epigean population of I. alipionis and no significant differences where found in morphology or degree of pigmentation. As the cave population is known for at least 30 years and is apparently isolated from epigean streams, it is classified as troglophilic. The discovery of this troglophilic species in the Santana Cave is an additional strong argument for the conservation of that cave.

  19. The Caves of Naica: a decade of research

    International Nuclear Information System (INIS)

    Gazquez, F.; Calaforra, J. M.; Porti, P.; Badino, G.

    2016-01-01

    The caves of the Naica Mine have been the subject of study by scientists from up to seven counties over the past decade. Up to fifty research works have published to date, most relating to the origin of the giant selenite crystals of the Cueva de los Cristales. Nevertheless, a great deal of knowledge has been generated about other relevant aspects of the Naica system. This paper puts together the vast information available about the Naica caves, from the discovery of the Cueva de los Cristales in 2000 to the more recent investigations addressing mineralogy, microclimatology and the use of gypsum speleothems as a palaeo-environmental proxy. Special attention has been paid to novel research lines that have started to use the speleothems of Naica as a study case, particularly in fields such as Astrobiology and Planetary geology. Moreover, the conservation challenges which these caves will face in the near future as consequence of the end of mining activities have also been addressed in this article. (Author)

  20. Cave-dwelling bats (Mammalia: Chiroptera) and conservation concerns in South central Mindanao, Philippines

    OpenAIRE

    Krizler C. Tanalgo; John Aries G. Tabora

    2015-01-01

    The stable microclimate in caves provides a relatively constant habitat for many bat species in the Philippines, but human encroachment continues to disrupt this habitat and imperil many of the species roosting in the caves.  In South central Mindanao, the diversity and conservation status of cave bats remain undocumented and unexplored.  We employed mist-netting to capture bats from five different caves within the town of Kabacan, northern Cotabato, Philippines.  A total of 14 bat species we...

  1. Occurrence of organic wastewater and other contaminants in cave streams in northeastern Oklahoma and northwestern Arkansas

    Science.gov (United States)

    Bidwell, Joseph R.; Becker, C.; Hensley, S.; Stark, R.; Meyer, M.T.

    2010-01-01

    The prevalence of organic wastewater compounds in surface waters of the United States has been reported in a number of recent studies. In karstic areas, surface contaminants might be transported to groundwater and, ultimately, cave ecosystems, where they might impact resident biota. In this study, polar organic chemical integrative samplers (POCISs) and semipermeable membrane devices (SPMDs) were deployed in six caves and two surface-water sites located within the Ozark Plateau of northeastern Oklahoma and northwestern Arkansas in order to detect potential chemical contaminants in these systems. All caves sampled were known to contain populations of the threatened Ozark cavefish (Amblyopsis rosae). The surface-water site in Oklahoma was downstream from the outfall of a municipal wastewater treatment plant and a previous study indicated a hydrologic link between this stream and one of the caves. A total of 83 chemicals were detected in the POCIS and SPMD extracts from the surface-water and cave sites. Of these, 55 chemicals were detected in the caves. Regardless of the sampler used, more compounds were detected in the Oklahoma surface-water site than in the Arkansas site or the caves. The organic wastewater chemicals with the greatest mass measured in the sampler extracts included sterols (cholesterol and ??-sitosterol), plasticizers [diethylhexylphthalate and tris (2-butoxyethyl) phosphate], the herbicide bromacil, and the fragrance indole. Sampler extracts from most of the cave sites did not contain many wastewater contaminants, although extracts from samplers in the Oklahoma surfacewater site and the cave hydrologically linked to it had similar levels of diethylhexyphthalate and common detections of carbamazapine, sulfamethoxazole, benzophenone, N-diethyl-3-methylbenzamide (DEET), and octophenol monoethoxylate. Further evaluation of this system is warranted due to potential ongoing transport of wastewaterassociated chemicals into the cave. Halogenated organics

  2. The significance of the second cave episode in Jerome’s Vita Malchi

    Directory of Open Access Journals (Sweden)

    Jacobus P. Kritzinger

    2014-02-01

    Full Text Available The authors argue that the second cave episode in Jerome’s Vita Malchi Monachi Captivi should, in view of the similarities with the first cave episode and the high incidence of literary devices employed in it, be recognised for its value in the interpretation of this vita. The book was intended as a defence of, and an exhortation to a life of celibacy and this dual purpose is clearly demonstrated in both episodes in which a cave is used as the setting. The second cave episode has been neglected in the scholarly debate about the purpose of the book and this article attempts to set the record straight.

  3. A conservation status index, as an auxiliary tool for the management of cave environments

    Directory of Open Access Journals (Sweden)

    Christiane Ramos Donato

    2014-09-01

    Full Text Available The conservation of the Speleological Heritage involves bioecological, geomorphological and anthropogenic studies, both from inside the caves and from the external environments that surround them. This study presents a method to rank caves according to their priority for conservation and restoration. Nine caves were evaluated: indicators related to the environmental impacts and the vulnerability status presented by those caves (intrinsic features and the values scored in a ‘Cave Conservation Index’ (CCI were established. We also used a rapid assessment protocol to measure cave vulnerability for prioritization of conservation/restoration actions (RAP-cr comparing natural cavities with the same lithology, due to “strictu sensu” peculiarities. Based on the protocols applied in caves of the municipality of Laranjeiras, Sergipe, Northeastern Brazil, we concluded that the present method attended to the needs for the classification of the caves into categories of conservation/restoration status, using little time and financial effort, through rapid diagnostics that facilitate the comparisons. In this perspective, the CCI can be used to indicate areas that should be protected and caves that should be prioritized to have initiated activities of conservation and restoration.

  4. The role of natural ventilation in the exposure to radon in the Postojna Cave

    Science.gov (United States)

    Gregorič, A.; Smerajec, M.; Vaupotič, J.

    2012-04-01

    Postojna Cave is the biggest of 21 show caves in Slovenia and one of present day's most visited show caves in the world. Long and branched out cave system, large entrances at different levels, inflow of the Pivka river, and large variation of the outdoor air temperature and precipitation, make the Postojna Cave also a very complex climatic system in which each part shows different conditions. The cave is only naturally ventilated and it is therefore characterised by high radon concentration, which depends on the ventilation regime in different seasons, resulting in typical annual cycles of radon levels in the cave air. Postojna Cave is a typical horizontal cave, where the difference between outside and cave air temperature represents the main driving force for air circulation. In winter, when the cave temperature is higher than outside, cave air is released from the cave into the outdoor atmosphere due to the air draught caused by the 'chimney effect', thus allowing fresh and cold outdoor air to enter the cave through low lying openings. This effect is not operative in summer, when the outside temperature is higher than in the cave, and air draught is minimal or reversed. In addition, air circulation can be locally altered due to other processes, like changing level of Pivka river during the rainy season and local geomorphologic characteristics of cave passages. High radon concentration in the Postojna Cave is the reason for thorough studies of the methodology for dose estimates of the personnel working in the cave. Due to high relative humidity and low air circulation, the cave air is characterised by very low particle concentration, which play an important role in radon dosimetry. Therefore parallel monitoring of radioactive aerosols of radon decay products (RnDP) and general (non-radioactive) aerosols in the particle size range of 10-1100 nm was performed in the air of Postojna Cave at the lowest point of tourist path in summer, winter and both transitional

  5. Environmental drivers of phototrophic biofilms in an Alpine show cave (SW-Italian Alps)

    International Nuclear Information System (INIS)

    Piano, E.; Bona, F.; Falasco, E.; La Morgia, V.; Badino, G.; Isaia, M.

    2015-01-01

    The proliferation of lampenflora is a major threat for the conservation of show caves, since phototrophic organisms cause physical, chemical and aesthetic damage to speleothems. In this paper we examine the environmental factors influencing the presence and the growth of the three main photosynthetic groups composing phototrophic biofilms in the Bossea show cave (SW-Italian Alps). The presence and the primary production of cyanobacteria, diatoms and green algae were detected with BenthoTorch®, an instrument for in situ measurement of chlorophyll a concentration that has never been used before in caves. By means of different techniques of regression analysis, we highlighted the response of the three photosynthetic groups to different environmental factors. Illuminance proved to be the main factor influencing positively both the probability of the presence and the productivity of the three groups. The presence of seeping water on the substrate and the distance from the cave entrance proved to play an important role in determining patterns of colonization. By means of GIS techniques, we provide thematic maps of the cave, providing a representation of pattern of the density of the three examined photosynthetic groups within different areas of the cave. The same approach may apply to other show caves, aiming at providing suggestions for the cave management (i.e. cleaning of the cave walls and positioning of artificial lights) and reduce impact caused by tourism. - Highlights: • We used a PAM fluorimeter on autotrophic biofilms in a show cave for the first time. • We modelled the environmental factors influencing phototrophic biofilms. • Illuminance, moisture and distance from the entrance proved to be significant. • We produced thematic maps illustrating our results. • We provide suggestions for cave management

  6. Environmental drivers of phototrophic biofilms in an Alpine show cave (SW-Italian Alps)

    Energy Technology Data Exchange (ETDEWEB)

    Piano, E., E-mail: elena.piano@unito.it [Department of Life Sciences and Systems Biology, University of Turin, Via Accademia Albertina 13, 10123 Turin (Italy); Bona, F.; Falasco, E. [Department of Life Sciences and Systems Biology, University of Turin, Via Accademia Albertina 13, 10123 Turin (Italy); La Morgia, V. [ISPRA, via Ca' Fornacetta, 9, 40064 Ozzano dell' Emilia (Italy); Badino, G. [Department of Physics, University of Turin, Via P. Giuria 1, 10125 Turin (Italy); Isaia, M. [Department of Life Sciences and Systems Biology, University of Turin, Via Accademia Albertina 13, 10123 Turin (Italy)

    2015-12-01

    The proliferation of lampenflora is a major threat for the conservation of show caves, since phototrophic organisms cause physical, chemical and aesthetic damage to speleothems. In this paper we examine the environmental factors influencing the presence and the growth of the three main photosynthetic groups composing phototrophic biofilms in the Bossea show cave (SW-Italian Alps). The presence and the primary production of cyanobacteria, diatoms and green algae were detected with BenthoTorch®, an instrument for in situ measurement of chlorophyll a concentration that has never been used before in caves. By means of different techniques of regression analysis, we highlighted the response of the three photosynthetic groups to different environmental factors. Illuminance proved to be the main factor influencing positively both the probability of the presence and the productivity of the three groups. The presence of seeping water on the substrate and the distance from the cave entrance proved to play an important role in determining patterns of colonization. By means of GIS techniques, we provide thematic maps of the cave, providing a representation of pattern of the density of the three examined photosynthetic groups within different areas of the cave. The same approach may apply to other show caves, aiming at providing suggestions for the cave management (i.e. cleaning of the cave walls and positioning of artificial lights) and reduce impact caused by tourism. - Highlights: • We used a PAM fluorimeter on autotrophic biofilms in a show cave for the first time. • We modelled the environmental factors influencing phototrophic biofilms. • Illuminance, moisture and distance from the entrance proved to be significant. • We produced thematic maps illustrating our results. • We provide suggestions for cave management.

  7. The genesis of a lava cave in the Deccan Volcanic Province (Maharashtra, India

    Directory of Open Access Journals (Sweden)

    Nikhil R. Pawar

    2016-01-01

    Full Text Available Lava tubes and channels forming lava distributaries have been recognized from different parts of western Deccan Volcanic Province (DVP. Openings of smaller dimension have been documented from the pāhoehoe flows around Pune, in the western DVP. A small lava cave is exposed in Ghoradeshwar hill, near Pune. Detailed field studies of the physical characteristics, structure and morphology of the flows hosting the lava tube has been carried out. This is the first detailed documentation of a lava cave from the DVP. The lava cave occurs in a compound pāhoehoe flow of Karla Formation, characterized by the presence of lobes, toes and small scale features like squeeze-ups. Field observations and measurements reveal that the dimensions of the cave are small, with low roof and a maximum width of 108 cm. The cave morphology along the 20 m passage varies from circular to semi-circular, with a twilight zone to the north. The gentle micro-topography at Ghoradeshwar controlled the advancement of pāhoehoe lobes and toes within the sheet lobe. The pre-flow gradients towards the north led to the progression of flow from the east, where the cave opening is presently seen. Dimensions and related morphology of the lava cave suggest that it can be best described as a small sub-crustal cave formed by draining of an inflated of pāhoehoe lava lobe. At Ghoradeshwar, besides the natural lava cave, Buddhist caves carved in pāhoehoe lava flows are also observed, indicating that early man took advantage of the existing openings in pāhoehoe flows and sculpted the caves to suit their requirements.

  8. Chemical Ecology of Cave-Dwelling Millipedes: Defensive Secretions of the Typhloiulini (Diplopoda, Julida, Julidae).

    Science.gov (United States)

    Makarov, Slobodan E; Bodner, Michaela; Reineke, Doris; Vujisić, Ljubodrag V; Todosijević, Marina M; Antić, Dragan Ž; Vagalinski, Boyan; Lučić, Luka R; Mitić, Bojan M; Mitov, Plamen; Anđelković, Boban D; Lucić, Sofija Pavković; Vajs, Vlatka; Tomić, Vladimir T; Raspotnig, Günther

    2017-04-01

    Cave animals live under highly constant ecological conditions and in permanent darkness, and many evolutionary adaptations of cave-dwellers have been triggered by their specific environment. A similar "cave effect" leading to pronounced chemical interactions under such conditions may be assumed, but the chemoecology of troglobionts is mostly unknown. We investigated the defensive chemistry of a largely cave-dwelling julid group, the controversial tribe "Typhloiulini", and we included some cave-dwelling and some endogean representatives. While chemical defense in juliform diplopods is known to be highly uniform, and mainly based on methyl- and methoxy-substituted benzoquinones, the defensive secretions of typhloiulines contained ethyl-benzoquinones and related compounds. Interestingly, ethyl-benzoquinones were found in some, but not all cave-dwelling typhloiulines, and some non-cave dwellers also contained these compounds. On the other hand, ethyl-benzoquinones were not detected in troglobiont nor in endogean typhloiuline outgroups. In order to explain the taxonomic pattern of ethyl-benzoquinone occurrence, and to unravel whether a cave-effect triggered ethyl-benzoquinone evolution, we classed the "Typhloiulini" investigated here within a phylogenetic framework of julid taxa, and traced the evolutionary history of ethyl-benzoquinones in typhloiulines in relation to cave-dwelling. The results indicated a cave-independent evolution of ethyl-substituted benzoquinones, indicating the absence of a "cave effect" on the secretions of troglobiont Typhloiulini. Ethyl-benzoquinones probably evolved early in an epi- or endogean ancestor of a clade including several, but not all Typhloiulus (basically comprising a taxonomic entity known as "Typhloiulus sensu stricto") and Serboiulus. Ethyl-benzoquinones are proposed as novel and valuable chemical characters for julid systematics.

  9. Bermuda: Search for Deep Water Caves 2009 on the R/V Endurance between 20090905 and 20090930

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Deep-water marine caves are one of the Earth's last largely unexplored frontiers of undiscovered fauna (animal life). More than 150 limestone caves are known to...

  10. Typhlonesticus gocmeni sp. n., a new cave-dwelling blind spider species from the Aegean region of Turkey (Araneae, Nesticidae

    Directory of Open Access Journals (Sweden)

    Carles Ribera

    2014-06-01

    Full Text Available A new species of the troglobitic spider genus Typhlonesticus is described from specimens found in Keloğlan Cave (Denizli Province, Dodurgalar Town, Turkey. Typhlonesticus gocmeni sp. n. is described on the basis of both sexes; and its phylogenetic relationships with closely related European genera and species are discussed based on morphological and molecular data (the cox1, rrnL and H3 genes. Three new combinations are proposed: Typhlonesticus idriacus (Roewer, 1931, comb. n., Typhlonesticus morisii (Brignoli, 1975 comb. n. and Typhlonesticus obcaecatus (Simon, 1907, comb. n. all ex. Nesticus.

  11. Ultra-precision bearings

    CERN Document Server

    Wardle, F

    2015-01-01

    Ultra-precision bearings can achieve extreme accuracy of rotation, making them ideal for use in numerous applications across a variety of fields, including hard disk drives, roundness measuring machines and optical scanners. Ultraprecision Bearings provides a detailed review of the different types of bearing and their properties, as well as an analysis of the factors that influence motion error, stiffness and damping. Following an introduction to basic principles of motion error, each chapter of the book is then devoted to the basic principles and properties of a specific type of bearin

  12. Feasibility Study of Padarangin Cave Slogohimo Wonogiri for Eco-Tourism

    Directory of Open Access Journals (Sweden)

    Kuswaji Dwi Priyono

    2004-01-01

    Full Text Available Area of Karst of mount Sewu in countryside of Padarangin own immeasurable of potency to be developed by besides activity of mining namely the tourism activity. Cave of nature found enable to can be developed as tourism, but date not yet been known how big potency of relevant tourism with the cave.  In line with the problems, this research aim to provide basic data of potency of cave and assess elegibility of cave. Padarangin for ecotourism in Wonogiri Regeny. Method used by survey of field and interview resident. Result of research indicate that cave of Padarangin have mount of cave at height 848 m msl which relative narrow, chamber horizontal as long as 63,8 m and vertical in 32,5 m. Needed by a special equipment to enter cave with capasities 10 – 15 people once the visit/incoming, owning value of sakral trusted by local society. The cave competent to be developed as tourism object of special enthusasm with visit limited.

  13. A world review of fungi, yeasts, and slime molds in caves

    Directory of Open Access Journals (Sweden)

    McAlpine Donald F.

    2013-01-01

    Full Text Available We provide a review of fungi, yeasts, and slime molds that have been found in natural solution caves and mines worldwide. Such habitats provide frequent roost sites for bats, and in eastern North America the environmental conditions that support white-nose syndrome, a lethal fungal disease currently devastating bat populations. A list of 1029 species of fungi, slime moulds, and yeasts in 518 genera have been documented from caves and mines worldwide in 225 articles. Ascomycota dominate the cave environment. Most research has been conducted in temperate climates, especially in Europe. A mean of 17.9±24.4SD fungal species are reported per study. Questions remain about the origin and ecological roles of fungi in caves, and which, if any, are cave-specialists. In the northern hemisphere, caves are generally characterized by relatively stable, low temperatures and a lack of organic substrates. This environment favors communities of oligotrophic, psychrotolerant fungi. Data that may help explain how cave environmental features and faunas inf luence the introduction and transmission of cave fungi remains scant.

  14. Phylogenetic diversity of fungal communities in areas accessible and not accessible to tourists in Naracoorte Caves.

    Science.gov (United States)

    Adetutu, Eric M; Thorpe, Krystal; Bourne, Steven; Cao, Xiangsheng; Shahsavari, Esmaeil; Kirby, Greg; Ball, Andrew S

    2011-01-01

    The fungal diversity in areas accessible and not accessible to tourists at UNESCO World Heritage-listed Naracoorte Caves was investigated with culture-dependent and culture-independent techniques for assistance in cave management protocol development. The caves were selected based on tourist numbers and configurations: Stick Tomato (open, high numbers), Alexandra (lockable openings, high numbers) and Strawhaven (control; no access). Culture-based survey revealed Ascomycota dominance irrespective of sampling area with Microascales (Trichurus sp.) being most frequently isolated. Some Hypocreales-like sequences belonging to Fusarium sp., Trichoderma sp. and Neonectria sp. (Stick Tomato) were cultured only from areas not accessible to tourists. These orders also were detected by DGGE assay irrespective of sampling area. The predominance of Ascomycota (especially Microascales) suggested their important ecological roles in these caves. Culture-independent analysis showed higher Shannon fungal diversity values (from ITS-based DGGE profiles) in tourist-accessible areas of these caves than in inaccessible areas with the fungal community banding patterns being substantially different in Stick Tomato Cave. Further investigations are needed to determine the cause of the differences in the fungal communities of Stick Tomato Cave, although cave-related factors such as use, configuration and sediment heterogeneity might have contributed to these differences.

  15. Identification of Martian Cave Skylights Using the Temperature Change During Day and Night

    Directory of Open Access Journals (Sweden)

    Jongil Jung

    2014-06-01

    Full Text Available Recently, cave candidates have been discovered on other planets besides the Earth, such as the Moon and Mars. When we go to other planets, caves could be possible human habitats providing natural protection from cosmic threats. In this study, seven cave candidates have been found on Pavonis Mons and Ascraeus Mons in Tharsis Montes on Mars. The cave candidates were selected using the images of the Context Camera (CTX on the Mars Reconnaissance Orbiter (MRO. The Context Camera could provide images with the high resolution of 6 meter per pixel. The diameter of the candidates ranges from 50 to 100m. Cushing et al. (2007 have analyzed the temperature change at daytime and nighttime using the Thermal Emission Imaging System (THEMIS for the sites of potential cave candidates. Similarly, we have examined the temperature change at daytime and at nighttime for seven cave candidates using the method of Cushing et al. (2007. Among those, only one candidate showed a distinct temperature change. However, we cannot verify a cave based on the temperature change only and further study is required for the improvement of this method to identify caves more clearly.

  16. Identification of Martian Cave Skylights Using the Temperature Change During Day and Night

    Science.gov (United States)

    Jung, Jongil; Yi, Yu; Kim, Eojin

    2014-06-01

    Recently, cave candidates have been discovered on other planets besides the Earth, such as the Moon and Mars. When we go to other planets, caves could be possible human habitats providing natural protection from cosmic threats. In this study, seven cave candidates have been found on Pavonis Mons and Ascraeus Mons in Tharsis Montes on Mars. The cave candidates were selected using the images of the Context Camera (CTX) on the Mars Reconnaissance Orbiter (MRO). The Context Camera could provide images with the high resolution of 6 meter per pixel. The diameter of the candidates ranges from 50 to 100m. Cushing et al. (2007) have analyzed the temperature change at daytime and nighttime using the Thermal Emission Imaging System (THEMIS) for the sites of potential cave candidates. Similarly, we have examined the temperature change at daytime and at nighttime for seven cave candidates using the method of Cushing et al. (2007). Among those, only one candidate showed a distinct temperature change. However, we cannot verify a cave based on the temperature change only and further study is required for the improvement of this method to identify caves more clearly.

  17. Aerosol particle size distribution in building and caves: impact to the radon-related dose evaluation

    International Nuclear Information System (INIS)

    Berka, Z.; Thinova, L.; Brandejsova, E.; Zdimal, V.; Fronka, A.; Milka, D.

    2004-01-01

    The results of evaluation of the aerosol particle size spectra observed in the Bozkov cave are presented and compared with the spectra observed in residential areas. The radon-to-dose conversion factor is discussed, as is the correction factor referred to as the cave factor. (P.A.)

  18. Metagenomic Analysis from the Interior of a Speleothem in Tjuv-Ante's Cave, Northern Sweden.

    Directory of Open Access Journals (Sweden)

    Marie Lisandra Zepeda Mendoza

    Full Text Available Speleothems are secondary mineral deposits normally formed by water supersaturated with calcium carbonate percolating into underground caves, and are often associated with low-nutrient and mostly non-phototrophic conditions. Tjuv-Ante's cave is a shallow-depth cave formed by the action of waves, with granite and dolerite as major components, and opal-A and calcite as part of the speleothems, making it a rare kind of cave. We generated two DNA shotgun sequencing metagenomic datasets from the interior of a speleothem from Tjuv-Ante's cave representing areas of old and relatively recent speleothem formation. We used these datasets to perform i an evaluation of the use of these speleothems as past biodiversity archives, ii functional and taxonomic profiling of the speleothem's different formation periods, and iii taxonomic comparison of the metagenomic results to previous microscopic analyses from a nearby speleothem of the same cave. Our analyses confirm the abundance of Actinobacteria and fungi as previously reported by microscopic analyses on this cave, however we also discovered a larger biodiversity. Interestingly, we identified photosynthetic genes, as well as genes related to iron and sulphur metabolism, suggesting the presence of chemoautotrophs. Furthermore, we identified taxa and functions related to biomineralization. However, we could not confidently establish the use of this type of speleothems as biological paleoarchives due to the potential leaching from the outside of the cave and the DNA damage that we propose has been caused by the fungal chemical etching.

  19. Sistema Faro, Isla de Mona, Puerto Rico: speleogenesis of the worlds largest flank margin cave

    International Nuclear Information System (INIS)

    Lace, M. J.; Kambesis, P. N.; Mylroie, J. E.

    2016-01-01

    Isla de Mona, a small, uplifted carbonate plateau jutting out of the waters of the Mona Passage, is an incredibly fragile and densely karstic environment. Expedition work was conducted by the Isla de Mona Project in cooperation with the Departamento Recursos Naturales y Ambientales de Puerto Rico (DRNA), including contributions from many researchers and cavers volunteering from across the U.S and Puerto Rico in the course of 12 separate expeditions, spanning a 14 year period (1998 to 2013). Over 200 caves have been documented on the island to date, the majority of this inventory is composed of flank margin caves but also includes sea caves, pit caves and talus caves. The most extensive example of cave development on the island is Sistema Faro - a sprawling maze-like series of chambers formed within the eastern point of the island with over 40 cliffside entrances overlooking the Caribbean Sea. Detailed cartography and analysis of the geomorphology and development of the Sistema Faro has helped form a complex model of carbonate island cave development as a function of tectonic uplift, lithology, sea level changes, karst hydrogeology and cliff retreat. This communication examines the roles these controls have played in the genesis of the world's largest flank margin cave. (Author)

  20. DNA analysis of fecal bacteria to augment an epikarst dye trace study at Crump's Cave, Kentucky

    Science.gov (United States)

    A rainfall simulation experiment was performed to investigate the transport behavior of fecal-derived bacteria through shallow karst soils and through the epikarst. The experiment was conducted at Cave Springs Cavern located just south of Mammoth Cave National Park on the Sinkhole Plain of South Cen...

  1. Geological conditions of origin of the Potočka zijalka cave

    Directory of Open Access Journals (Sweden)

    Stanko Buser

    2002-12-01

    Full Text Available In the Potočka zijalka cave on Mt. Ol{eva in Southern Karavanke during excavation of cave sediments of Würm age that contain cultural remains of the Cromagnon Man also large amounts of gravel were before the Badenian transgression, from the Central Alps during Miocene.

  2. Sediments of Biśnik Cave (Poland): Lithology and stratigraphy of the Middle Palaeolithic site

    Czech Academy of Sciences Publication Activity Database

    Krajcarz, M. T.; Bosák, Pavel; Šlechta, Stanislav; Pruner, Petr; Komar, M.; Dresler, J.; Madeyska, T.

    326/327, April (2014), s. 6-19 ISSN 1040-6182 R&D Projects: GA AV ČR IAA300130701 Institutional research plan: CEZ:AV0Z30130516 Institutional support: RVO:67985831 Keywords : karsology * caves * Biśnik Cave (Poland) Subject RIV: DB - Geology ; Mineralogy Impact factor: 2.062, year: 2014

  3. Mimogonellus dreybrodti sp. n., a new cave-inhabiting Osoriinae from Laos (Coleoptera: Staphylinidae).

    Science.gov (United States)

    Yin, Zi-Wei; Steiner, Helmut

    2017-10-17

    A new osoriine species, Mimogonellus dreybrodti Yin & Steiner, sp. n., collected from a cave in Houaphanh Province, Laos, is described and illustrated. This represents the third Mimogonellus species in Asia, and the first in the genus known to inhabit a cave environment.

  4. Phylogeography of Sardinian cave salamanders (genus Hydromantes) is mainly determined by geomorphology.

    Science.gov (United States)

    Chiari, Ylenia; van der Meijden, Arie; Mucedda, Mauro; Lourenço, João M; Hochkirch, Axel; Veith, Michael

    2012-01-01

    Detecting the factors that determine the interruption of gene flow between populations is key to understanding how speciation occurs. In this context, caves are an excellent system for studying processes of colonization, differentiation and speciation, since they represent discrete geographical units often with known geological histories. Here, we asked whether discontinuous calcareous areas and cave systems represent major barriers to gene flow within and among the five species of Sardinian cave salamanders (genus Hydromantes) and whether intraspecific genetic structure parallels geographic distance within and among caves. We generated mitochondrial cytochrome b gene sequences from 184 individuals representing 48 populations, and used a Bayesian phylogeographic approach to infer possible areas of cladogenesis for these species and reconstruct historical and current dispersal routes among distinct populations. Our results show deep genetic divergence within and among all Sardinian cave salamander species, which can mostly be attributed to the effects of mountains and discontinuities in major calcareous areas and cave systems acting as barriers to gene flow. While these salamander species can also occur outside caves, our results indicate that there is a very poor dispersal of these species between separate cave systems.

  5. Distribution of meiofaunal abundances in a marine cave complex with secondary openings and freshwater filtrations

    DEFF Research Database (Denmark)

    Riera, Rodrigo; Monterroso, Óscar; Núñez, Jorge

    2018-01-01

    Submerged sea caves are priority areas for conservation according to the Habitat Directive 92/43/CEE because of their unique biodiversity. A limited number of publications exist about communities living on sediments inside caves, mostly focused on the macrofaunal fraction (>0.5-mm body size). Mei...

  6. Pisgah Lava Cave Communication Test: Science Case Study for the Networked Constellations Initiative

    Science.gov (United States)

    Belov, K.; Ellison, D.; Fraeman, A.

    2017-01-01

    As part of the science case study for the Networked Constellations initiative, a team of JPL scientists explore the possibility of a mission to study the lava caves on Mars. Natural caves on Mars and the Moon present a unique opportunity to learn about the planetary geology and to provide a shelter for human explorers. Due to power and communication challenges, a network of assets has significant advantages over a single asset sent inside a cave. However, communication between the assets and the data downlink present significant difficulties due to the presence of rough walls, boulders, and other obstacles with unknown dielectric constant inside a typical cave, disturbing the propagation of the radio waves. A detailed study is needed to establish the limitations of the current communication technologies and to develop requirements for the new communication technology applicable to the cave environment. On May 4 of 2017, Konstantin Belov, Doug Ellison, and Abby Fraeman visited a lava cave in Pisgah, CA. The purpose of the visit was to build a 3D map of the cave, which could be used to create a model of radio wave propagation, and to conduct a series of communication tests using off-the-shelf equipment to verify the in-cave communication challenges. This experiment should be considered as a simple 'proof of concept' and is the subject of this report.

  7. Hydrogeology of the Sterkfontein Cave System, Cradle of Humankind, South Africa

    CSIR Research Space (South Africa)

    Hobbs, Philip J

    2017-09-01

    Full Text Available A water level rise of almost 3 m in the space of two years in the Sterkfontein Cave system since late-2009 necessitated the re-routing of the tourist path through the cave to successively higher elevations on three occasions. It also raisedconcern...

  8. 36 CFR 290.3 - Nomination, evaluation, and designation of significant caves.

    Science.gov (United States)

    2010-07-01

    ..., DEPARTMENT OF AGRICULTURE CAVE RESOURCES MANAGEMENT § 290.3 Nomination, evaluation, and designation of... on National Forest System lands shall possess one or more of the following features, characteristics... information. (4) Hydrologic. The cave is a part of a hydrologic system or contains water which is important to...

  9. Invertebrate fossils from cave sediments: A new proxy for pre-Quaternary paleoenvironments

    Czech Academy of Sciences Publication Activity Database

    Moldovan, O.T.; Mihevc, A.; Miko, L.; Constantin, S.; Meleg, I. N.; Petculescu, A.; Bosák, Pavel

    2011-01-01

    Roč. 8, č. 7 (2011), s. 1825-1837 ISSN 1726-4170 R&D Projects: GA AV ČR IAA300130701 Institutional research plan: CEZ:AV0Z30130516 Keywords : fossil invertebrates * Oribatida * Pliocene/Pleistocene * caves * caves (Slovenia) Subject RIV: DB - Geology ; Mineralogy Impact factor: 3.859, year: 2011

  10. Application of Ground Penetrating Radar Supported by Mineralogical-Geochemical Methods for Mapping Unroofed Cave Sediments

    Directory of Open Access Journals (Sweden)

    Teja Čeru

    2018-04-01

    Full Text Available Ground penetrating radar (GPR using a special unshielded 50 MHz Rough Terrain Antenna (RTA in combination with a shielded 250 MHz antenna was used to study the capability of this geophysical method for detecting cave sediments. Allochthonous cave sediments found in the study area of Lanski vrh (W Slovenia are now exposed on the karst surface in the so-called “unroofed caves” due to a general lowering of the surface (denudation of carbonate rocks and can provide valuable evidence of the karst development. In the first phase, GPR profiles were measured at three test locations, where cave sediments are clearly evident on the surface and appear with flowstone. It turned out that cave sediments are clearly visible on GPR radargrams as areas of strong signal attenuation. Based on this finding, GPR profiling was used in several other places where direct indicators of unroofed caves or other indicators for speleogenesis are not present due to strong surface reshaping. The influence of various field conditions, especially water content, on GPR measurements was also analysed by comparing radargrams measured in various field conditions. Further mineralogical-geochemical analyses were conducted to better understand the factors that influence the attenuation in the area of cave sediments. Samples of cave sediments and soils on carbonate rocks (rendzina were taken for X-ray diffraction (XRD and X-ray fluorescence (XRF analyses to compare the mineral and geochemical compositions of both sediments. Results show that cave sediments contain higher amounts of clay minerals and iron/aluminium oxides/hydroxides which, in addition to the thickness of cave sediments, can play an important role in the depth of penetration. Differences in the mineral composition also lead to water retention in cave sediments even through dry periods which additionally contribute to increased attenuation with respect to surrounding soils. The GPR method has proven to be reliable for

  11. Roller bearing geometry design

    Science.gov (United States)

    Savage, M.; Pinkston, B. H. W.

    1976-01-01

    A theory of kinematic stabilization of rolling cylinders is extended and applied to the design of cylindrical roller bearings. The kinematic stabilization mechanism puts a reverse skew into the rolling elements by changing the roller taper. Twelve basic bearing modification designs are identified amd modeled. Four have single transverse convex curvature in their rollers while eight have rollers which have compound transverse curvature made up of a central cylindrical band surrounded by symmetric bands with slope and transverse curvature. The bearing designs are modeled for restoring torque per unit axial displacement, contact stress capacity, and contact area including dynamic loading, misalignment sensitivity and roller proportion. Design programs are available which size the single transverse curvature roller designs for a series of roller slopes and load separations and which design the compound roller bearings for a series of slopes and transverse radii of curvature. The compound rollers are proportioned to have equal contact stresses and minimum size. Design examples are also given.

  12. DW_BEAR

    Data.gov (United States)

    Department of Homeland Security — Subset of BEAR (Bi-Weekly Examination Analysis and Reporting) data used for financial audit remediation reporting within the Coast Guard Business Intelligence (CGBI)...

  13. Stability numerical analysis of soil cave in karst area to drawdown of underground water level

    Science.gov (United States)

    Mo, Yizheng; Xiao, Rencheng; Deng, Zongwei

    2018-05-01

    With the underground water level falling, the reliable estimates of the stability and deformation characteristics of soil caves in karst region area are required for analysis used for engineering design. Aimed at this goal, combined with practical engineering and field geotechnical test, detail analysis on vertical maximum displacement of top, vertical maximum displacement of surface, maximum principal stress and maximum shear stress were conducted by finite element software, with an emphasis on two varying factors: the size and the depth of soil cave. The calculations on the soil cave show that, its stability of soil cave is affected by both the size and depth, and only when extending a certain limit, the collapse occurred along with the falling of underground water; Additionally, its maximum shear stress is in arch toes, and its deformation curve trend of maximum displacement is similar to the maximum shear stress, which further verified that the collapse of soil cave was mainly due to shear-failure.

  14. Effect of soil-rock system on speleothems weathering in Bailong Cave, Yunnan Province, China*

    Science.gov (United States)

    Wang, Jing; Song, Lin-hua

    2005-01-01

    Bailong Cave with its well-developed Middle Triassic calcareous dolomite’s system was opened as a show cave for visitors in 1988. The speleothem scenery has been strongly weathered as white powder on the outer layers. Study of the cave winds, permeability of soil-rock system and the chemical compositions of the dripping water indicated: (1) The cave dimension structure distinctively affects the cave winds, which were stronger at narrow places. (2) Based on the different soil grain size distribution, clay was the highest in composition in the soil. The response sense of dripping water to the rainwater percolation was slow. The density of joints and other openings in dolomite make the dolomite as mesh seepage body forming piles of thin and high columns and stalactites. (3) Study of 9 dripping water samples by HYDROWIN computer program showed that the major mineral in the water was dolomite. PMID:15682505

  15. Occupational exposure to radon in Australian Tourist Caves an Australian-wide study of radon levels

    Energy Technology Data Exchange (ETDEWEB)

    Solomon, S B; Langroo, R; Peggie, J R [Australian Radiation Laboratory. Yallambie, VIC (Australia); Lyons, R G [University of Auckland, Auckland, (New Zealand). Department of Physics; James, J M [University of Sydney, Sydney, NSW (Australia). Department of Chemisty

    1996-02-01

    The study described in this report sets out to determine which Australian show caves have long- term radon levels in excess of the proposed action level of 1000 Bq m{sup -3}. The collaborative study between the Australian Radiation Laboratory (ARL), the University of Sydney and the University of Auckland, was carried out with the support of a Research Grant from Worksafe Australia. The aims of this study were to measure radon levels for each season over a period of one year, at representative sites in all developed show caves around Australia, to determine yearly average radon levels for each cave tour, based on these site measurements, to estimate the radiation doses to the tour guides employed in these caves, and to identify caves with radon concentrations in excess of the action level. (authors) 7 refs., 10 tabs., 2 figs.

  16. Occupational exposure to radon in Australian Tourist Caves an Australian-wide study of radon levels

    International Nuclear Information System (INIS)

    Solomon, S.B.; Langroo, R.; Peggie, J.R.; Lyons, R.G.; James, J.M.

    1996-02-01

    The study described in this report sets out to determine which Australian show caves have long- term radon levels in excess of the proposed action level of 1000 Bq m -3 . The collaborative study between the Australian Radiation Laboratory (ARL), the University of Sydney and the University of Auckland, was carried out with the support of a Research Grant from Worksafe Australia. The aims of this study were to measure radon levels for each season over a period of one year, at representative sites in all developed show caves around Australia, to determine yearly average radon levels for each cave tour, based on these site measurements, to estimate the radiation doses to the tour guides employed in these caves, and to identify caves with radon concentrations in excess of the action level. (authors)

  17. U-series dating of Paleolithic art in 11 caves in Spain.

    Science.gov (United States)

    Pike, A W G; Hoffmann, D L; García-Diez, M; Pettitt, P B; Alcolea, J; De Balbín, R; González-Sainz, C; de las Heras, C; Lasheras, J A; Montes, R; Zilhão, J

    2012-06-15

    Paleolithic cave art is an exceptional archive of early human symbolic behavior, but because obtaining reliable dates has been difficult, its chronology is still poorly understood after more than a century of study. We present uranium-series disequilibrium dates of calcite deposits overlying or underlying art found in 11 caves, including the United Nations Educational, Scientific, and Cultural Organization (UNESCO) World Heritage sites of Altamira, El Castillo, and Tito Bustillo, Spain. The results demonstrate that the tradition of decorating caves extends back at least to the Early Aurignacian period, with minimum ages of 40.8 thousand years for a red disk, 37.3 thousand years for a hand stencil, and 35.6 thousand years for a claviform-like symbol. These minimum ages reveal either that cave art was a part of the cultural repertoire of the first anatomically modern humans in Europe or that perhaps Neandertals also engaged in painting caves.

  18. The Astrobiology of the Subsurface: Exploring Cave Habitats on Earth, Mars and Beyond

    Science.gov (United States)

    Boston, Penelope Jane

    2016-01-01

    We are using the spectacular underground landscapes of Earth caves as models for the subsurfaces of other planets. Caves have been detected on the Moon and Mars and are strongly suspected for other bodies in the Solar System including some of the ice covered Ocean Worlds that orbit gas giant planets. The caves we explore and study include many extreme conditions of relevance to planetary astrobiology exploration including high and low temperatures, gas atmospheres poisonous to humans but where exotic microbes can flourish, highly acidic or salty fluids, heavy metals, and high background radiation levels. Some cave microorganisms eat their way through bedrock, some live in battery acid conditions, some produce unusual biominerals and rare cave formations, and many produce compounds of potential pharmaceutical and industrial significance. We study these unique lifeforms and the physical and chemical biosignatures that they leave behind. Such traces can be used to provide a "Field Guide to Unknown Organisms" for developing life detection space missions.

  19. Detecting and characterizing unroofed caves by ground penetrating radar

    Science.gov (United States)

    Čeru, Teja; Šegina, Ela; Knez, Martin; Benac, Čedomir; Gosar, Andrej

    2018-02-01

    The bare karst surface in the southeastern part of Krk Island (Croatia) is characterized by different surface karst features, such as valley-like shallow linear depressions and partially or fully sediment-filled depressions of various shapes and sizes. They were noticed due to locally increased thickness of sediment and enhanced vegetation but had not yet been systematically studied and defined. Considering only the geometry of the investigated surface features and the rare traces of cave environments detected by field surveys, it was unclear which processes (surface karstification and/or speleogenesis) contributed most to their formation. The low-frequency ground penetrating radar (GPR) method using a special 50 MHz RTA antenna was applied to study and describe these karst features. Three study sites were chosen and 5 km of GPR profiles were positioned to include various surface features. The results obtained from the GPR investigation lead to the following conclusions: (1) an increased thickness of sediment was detected in all the investigated depressions indicating their considerable depth; (2) areas between different depressions expressed as attenuated zones in GPR images reveal their interconnection; (3) transitions between surface and underground features are characterized by a collapsed passage visible in the GPR data; and (4) an underground continuation of surface valley-like depressions was detected, proving the speleogenetic origin of such features. Subsurface information obtained using GPR indicates that the valley-like depressions, irregular depressions completely or partially filled with sediment, and some dolines are associated with a nearly 4 km-long unroofed cave and developed as a result of karst denudation. In the regional context, these results suggest long-lasting karstification processes in the area, in contrast to the pre-karstic fluvial phase previously assumed to have occurred here. This research is the first application of the GPR method to

  20. Exposure to radon in the Gadime Cave, Kosovo.

    Science.gov (United States)

    Bahtijari, M; Vaupotic, J; Gregoric, A; Stegnar, P; Kobal, I

    2008-02-01

    Air radon concentration was measured in summer and winter at 11 points along the tourist guided route in the Gadime Cave in Kosovo using alpha scintillation cells and etched track detectors. At two points in summer, values higher than 1700Bqm(-3) were observed; they otherwise were in the range 400-1000Bqm(-3). Values were lower in winter. The effective dose received by a person during a 90min visit is 3.7microSv in summer and 2.5microSv in winter. For a tourist guide the annual effective dose is less than 3.5mSv.

  1. Exposure to radon in the Gadime Cave, Kosovo

    International Nuclear Information System (INIS)

    Bahtijari, M.; Vaupotic, J.; Gregoric, A.; Stegnar, P.; Kobal, I.

    2008-01-01

    Air radon concentration was measured in summer and winter at 11 points along the tourist guided route in the Gadime Cave in Kosovo using alpha scintillation cells and etched track detectors. At two points in summer, values higher than 1700 Bq m -3 were observed; they otherwise were in the range 400-1000 Bq m -3 . Values were lower in winter. The effective dose received by a person during a 90 min visit is 3.7 μSv in summer and 2.5 μSv in winter. For a tourist guide the annual effective dose is less than 3.5 mSv

  2. Exposure to radon in the Gadime Cave, Kosovo

    Energy Technology Data Exchange (ETDEWEB)

    Bahtijari, M. [Faculty of Education, University of Prishtina, Prishtina, Kosovo (Country Unknown); Vaupotic, J.; Gregoric, A.; Stegnar, P. [Jozef Stefan Institute, PO Box 3000, 1001 Ljubljana (Slovenia); Kobal, I. [Jozef Stefan Institute, PO Box 3000, 1001 Ljubljana (Slovenia)], E-mail: ivan.kobal@ijs.si

    2008-02-15

    Air radon concentration was measured in summer and winter at 11 points along the tourist guided route in the Gadime Cave in Kosovo using alpha scintillation cells and etched track detectors. At two points in summer, values higher than 1700 Bq m{sup -3} were observed; they otherwise were in the range 400-1000 Bq m{sup -3}. Values were lower in winter. The effective dose received by a person during a 90 min visit is 3.7 {mu}Sv in summer and 2.5 {mu}Sv in winter. For a tourist guide the annual effective dose is less than 3.5 mSv.

  3. 118-C-4 Horizontal Rod Cave Characterization Report

    International Nuclear Information System (INIS)

    Encke, B.D.; Thoren, R.A.

    1998-03-01

    This report addresses the characterization data collected from 118-C- 4 Horizontal Rod Cave in December 1996 and August 1997. The characterization activities evaluated the radiological status and identified hazardous materials locations. The scope of this report is limited to the 118-C-4 Facility Structure. Information in this report can be used to identify the waste streams, provide specific chemical and radiological data to aid in planning decontamination and decommissioning (D ampersand D) activities, and allow proper disposal of the demolition debris, as required by the Comprehensive Environmental Response, Compensation, and Liability Act of 1980

  4. Designing user models in a virtual cave environment

    Energy Technology Data Exchange (ETDEWEB)

    Brown-VanHoozer, S. [Argonne National Lab., Idaho Falls, ID (United States); Hudson, R. [Argonne National Lab., IL (United States); Gokhale, N. [Madge Networks, San Jose, CA (United States)

    1995-12-31

    In this paper, the results of a first study into the use of virtual reality for human factor studies and design of simple and complex models of control systems, components, and processes are described. The objective was to design a model in a virtual environment that would reflect more characteristics of the user`s mental model of a system and fewer of the designer`s. The technology of a CAVE{trademark} virtual environment and the methodology of Neuro Linguistic Programming were employed in this study.

  5. Rolling bearing analysis

    CERN Document Server

    Harris, Tedric A

    2001-01-01

    One of the most well-known experts in the field brings cutting-edge research to practitioners in the new edition of this important reference. Covers the improved mathematical calculations for rolling bearing endurance developed by the American Society of Mechanical Engineers and the Society of Lubrication and Tribology Engineers. Updated with new material on Condition-Based Maintenance, new testing methods, and new bearing materials.

  6. Gear bearing drive

    Science.gov (United States)

    Mavroidis, Constantinos (Inventor); Vranish, John M. (Inventor); Weinberg, Brian (Inventor)

    2011-01-01

    A gear bearing drive provides a compact mechanism that operates as an actuator providing torque and as a joint providing support. The drive includes a gear arrangement integrating an external rotor DC motor within a sun gear. Locking surfaces maintain the components of the drive in alignment and provide support for axial loads and moments. The gear bearing drive has a variety of applications, including as a joint in robotic arms and prosthetic limbs.

  7. Load responsive hydrodynamic bearing

    Science.gov (United States)

    Kalsi, Manmohan S.; Somogyi, Dezso; Dietle, Lannie L.

    2002-01-01

    A load responsive hydrodynamic bearing is provided in the form of a thrust bearing or journal bearing for supporting, guiding and lubricating a relatively rotatable member to minimize wear thereof responsive to relative rotation under severe load. In the space between spaced relatively rotatable members and in the presence of a liquid or grease lubricant, one or more continuous ring shaped integral generally circular bearing bodies each define at least one dynamic surface and a plurality of support regions. Each of the support regions defines a static surface which is oriented in generally opposed relation with the dynamic surface for contact with one of the relatively rotatable members. A plurality of flexing regions are defined by the generally circular body of the bearing and are integral with and located between adjacent support regions. Each of the flexing regions has a first beam-like element being connected by an integral flexible hinge with one of the support regions and a second beam-like element having an integral flexible hinge connection with an adjacent support region. A least one local weakening geometry of the flexing region is located intermediate the first and second beam-like elements. In response to application of load from one of the relatively rotatable elements to the bearing, the beam-like elements and the local weakening geometry become flexed, causing the dynamic surface to deform and establish a hydrodynamic geometry for wedging lubricant into the dynamic interface.

  8. Genotyping of Capreolus pygargus fossil DNA from Denisova cave reveals phylogenetic relationships between ancient and modern populations.

    Directory of Open Access Journals (Sweden)

    Nadezhda V Vorobieva

    Full Text Available BACKGROUND: The extant roe deer (Capreolus Gray, 1821 includes two species: the European roe deer (C. capreolus and the Siberian roe deer (C. pygargus that are distinguished by morphological and karyotypical differences. The Siberian roe deer occupies a vast area of Asia and is considerably less studied than the European roe deer. Modern systematics of the Siberian roe deer remain controversial with 4 morphological subspecies. Roe deer fossilized bones are quite abundant in Denisova cave (Altai Mountains, South Siberia, where dozens of both extant and extinct mammalian species from modern Holocene to Middle Pleistocene have been retrieved. METHODOLOGY/PRINCIPAL FINDINGS: We analyzed a 629 bp fragment of the mitochondrial control region from ancient bones of 10 Holocene and four Pleistocene Siberian roe deer from Denisova cave as well as 37 modern specimen belonging to populations from Altai, Tian Shan (Kyrgyzstan, Yakutia, Novosibirsk region and the Russian Far East. Genealogical reconstructions indicated that most Holocene haplotypes were probably ancestral for modern roe deer populations of Western Siberia and Tian Shan. One of the Pleistocene haplotypes was possibly ancestral for modern Yakutian populations, and two extinct Pleistocene haplotypes were close to modern roe deer from Tian Shan and Yakutia. Most modern geographical populations (except for West Siberian Plains are heterogeneous and there is some tentative evidence for structure. However, we did not find any distinct phylogenetic signal characterizing particular subspecies in either modern or ancient samples. CONCLUSION/SIGNIFICANCE: Analysis of mitochondrial DNA from both ancient and modern samples of Siberian roe deer shed new light on understanding the evolutionary history of roe deer. Our data indicate that during the last 50,000 years multiple replacements of populations of the Siberian roe deer took place in the Altai Mountains correlating with climatic changes. The Siberian

  9. Geological constraints on cave development in the plateau-gorge karst of South China (Wulong, Chongqing)

    Science.gov (United States)

    Szczygieł, Jacek; Golicz, Mateusz; Hercman, Helena; Lynch, Erin

    2018-03-01

    The Houping Tiankeng cluster is a part of the South China Karst UNESCO World Natural Heritage Site. Within the distinctive Wulong plateau-gorge karst, > 200 km of cave passages have been documented to date. This paper focuses on detailed tectonic and morphological research on the Luo Shui Kong cave, enriched with U-series dating of speleothems and complemented by morphometric analysis of the San Wang Dong and Er Wang Dong caves. All of these caves exhibit three regional levels of cave development: 1) 1040-1020 m a.s.l.; 2) 900-840 m a.s.l.; and 3) 740-660 m a.s.l. The Houping Tiankeng area is a carbonate rock sequence several hundred meters thick, overlain by the less soluble Lower Ordovician strata, limiting recharge points to faults exposing underlying easily soluble formations. This leads to the domination of concentrated, high-volume inflow and thus results in caves of large volume in the plateau-gorge karst. Shafts connecting the surface with cave passages located underneath formed along faults, changing the hydrogeological pattern through karst water capture and remodeling of existing conduits, albeit mainly by increasing their overall dimensions rather than by deepening them. The most favorable structures for cave-level development are two sets of joints conjugated with gently inclined bedding. Since these joints are characterized by a small vertical extent, downward development is limited. Hence, most of the passages are wide but not deep canyons and typical of a water-table cave pattern. Places where the fault plane is eroded from the surface and where, at the same time, an underneath cave chamber ceiling expands upwards are particularly predisposed to the formation of a tiankeng.

  10. Microbial communities in dark oligotrophic volcanic ice cave ecosystems of Mt. Erebus, Antarctica

    Directory of Open Access Journals (Sweden)

    Bradley M. Tebo

    2015-03-01

    Full Text Available The Earth’s crust hosts a subsurface, dark, and oligotrophic biosphere that is poorly understood in terms of the energy supporting its biomass production and impact on food webs at the Earth’s surface. Dark oligotrophic volcanic ecosystems (DOVEs are good environments for investigations of life in the absence of sunlight as they are poor in organics, rich in chemical reactants and well known for chemical exchange with Earth’s surface systems. Ice caves near the summit of Mt. Erebus (Antarctica offer DOVEs in a polar alpine environment that is starved in organics and with oxygenated hydrothermal circulation in highly reducing host rock. We surveyed the microbial communities using PCR, cloning, sequencing and analysis of the small subunit (16S ribosomal and Ribulose-1,5-bisphosphate Carboxylase/Oxygenase (RubisCO genes in sediment samples from three different caves, two that are completely dark and one that receives snow-filtered sunlight seasonally. The microbial communities in all three caves are composed primarily of Bacteria and fungi; Archaea were not detected. The bacterial communities from these ice caves display low phylogenetic diversity, but with a remarkable diversity of RubisCO genes including new deeply branching Form I clades, implicating the Calvin-Benson-Bassham cycle as a pathway of CO2 fixation. The microbial communities in one of the dark caves, Warren Cave, which has a remarkably low phylogenetic diversity, were analyzed in more detail to gain a possible perspective on the energetic basis of the microbial ecosystem in the cave. Atmospheric carbon (CO2 and CO, including from volcanic emissions, likely supplies carbon and/or some of the energy requirements of chemoautotrophic microbial communities in Warren Cave and probably other Mt. Erebus ice caves. Our work casts a first glimpse at Mt. Erebus ice caves as natural laboratories for exploring carbon, energy and nutrient sources in the subsurface biosphere and the

  11. SKB WP-cave project. Radionuclide release from the near-field in a WP-cave repository

    International Nuclear Information System (INIS)

    Lindgren, M.; Skagius, K.

    1989-04-01

    The release of radionuclides from the bentonite-sand barrier (near-field) in a WP-cave repository for high level radioactive waste has been studied. Calculations were made for two cases; a Low Flow Through Case and a High Flow Through Case. The difference between the two cases lies in the assumed hydraulic properties of the bentonite-sand barrier and the system inside the barrier. The effect on the nuclide release of solubility limitations, sorption capacity of the barriers, radiolytic fuel oxidation rate as well as the thickness of the bentonite-sand barrier, were also investigated for the Low Flow Through Case. (authors)

  12. Late Holocene environmental reconstruction using cave sediments from Belize

    Science.gov (United States)

    Polk, Jason S.; van Beynen, Philip E.; Reeder, Philip P.

    2007-07-01

    Cave sediments collected from Reflection Cave on the Vaca Plateau, Belize show variations in the δ13C values of their fulvic acids (FAs), which indicate periods of vegetation change caused by climatic and Maya influences during the late Holocene. The δ13C values range from - 27.11‰ to - 21.52‰, a shift of ˜ 5.59‰, which suggests fluctuating contributions of C 3 and C 4 plants throughout the last 2.5 ka, with C 4 plant input reflecting periods of Maya agriculture. Maya activity in the study area occurred at different intensities from ˜ 2600 cal yr BP until ˜ 1500 cal yr BP, after which agricultural practices waned as the Maya depopulated the area. These changes in plant assemblages were in response to changes in available water resources, with increased aridity leading to the eventual abandonment of agricultural areas. The Ix Chel archaeological site, located in the study area, is a highland site that would have been among the first agricultural settlements to be affected during periods of aridity. During these periods, minimal water resources would have been available in this highly karstified, well-drained area, and supplemental groundwater extraction would have been difficult due to the extreme depth of the water table.

  13. Forensic Fluid Dynamics and the Indian Spring (1991) cave collapse problem

    Science.gov (United States)

    Nof, D.

    2013-05-01

    The collapse of the Indian spring cave (Florida) in 1991 was unique because it occurred while cave divers were in the cave. For the most part, the submerged cave is large enough to accommodate a passing truck so the cave divers were not in touch with its walls and it is hard to imagine why would it naturally collapse just when the divers were in it. Recently, Nof and Paldor (2010) resolved this apparent paradox by suggesting that resonance in the air pockets in the cavern, created by breathing (open circuit) divers, may have contributed to the collapse. In this scenario, divers present in the cavern during the dive may have (unknowingly) caused the collapse through the pressurized air/gas that they release with each breath. When the breathing period of the diver(s) matches the natural oscillations period of the "cave oscillator", the ensuing resonance causes the air pressure in the pockets to increase uncontrollably. Here, we place the above theory on a more solid ground. To do so, we first extended the resonance theory from our original two-pockets, symmetrical U-tube model (with two identical branches that were not specifically identified within the cave system) to a one (identified) pocket in the cavern and a very broad basin (identified, of course) that serves as the other branch of the U-tube. Our methodology is to apply familiar fluid dynamics principles to the situation that occurred in the cave. We did so, step-by-step, on the basis of our interviews with four out of the five surviving cave-divers. Namely, we dissected their testimonies to arrive at a physically plausible scenario determined on basis of a fluid dynamics application to the natural flow in the cave and the flow induced by the compressed air released by the divers as well as the collapsed mud. We found that the oscillation period was larger than what we earlier calculated (still relevant to the case, nevertheless), and that, in contrast to what most cave divers believe, there was a temporary

  14. Climate Drives Polar Bear Origins

    Science.gov (United States)

    In their provocative analysis of northern bears (“Nuclear genomic sequences reveal that polar bears are an old and distinct bear lineage,” Reports, 20 April, p. 344), F. Hailer et al. use independent nuclear loci to show that polar bears originated during the middle Pleistocene, rather than during t...

  15. Watchable Wildlife: The Black Bear

    Science.gov (United States)

    Lynn L. Rogers

    1992-01-01

    Black bears are the bears people most often encounter. Black bears live in forests over much of North America, unlike grizzlies that live only in Alaska, northern and western Canada, and the northern Rocky Mountains. This brochure presents the latest information on black bear life and how this species responds to an ever-increasing number of campers, hikers, and...

  16. European Union

    International Nuclear Information System (INIS)

    Schaller, K.

    1995-01-01

    Different instruments used by European Commission of the European Union for financial support radioactive waste management activities in the Russian Federation are outlined. Three particular programmes in the area are described

  17. Tribology of alternative bearings.

    Science.gov (United States)

    Fisher, John; Jin, Zhongmin; Tipper, Joanne; Stone, Martin; Ingham, Eileen

    2006-12-01

    The tribological performance and biological activity of the wear debris produced has been compared for highly cross-linked polyethylene, ceramic-on-ceramic, metal-on-metal, and modified metal bearings in a series of in vitro studies from a single laboratory. The functional lifetime demand of young and active patients is 10-fold greater than the estimated functional lifetime of traditional polyethylene. There is considerable interest in using larger diameter heads in these high demand patients. Highly cross-linked polyethylene show a four-fold reduction in functional biological activity. Ceramic-on-ceramic bearings have the lowest wear rates and least reactive wear debris. The functional biological activity is 20-fold lower than with highly cross-linked polyethylene. Hence, ceramic-on-ceramic bearings address the tribological lifetime demand of highly active patients. Metal-on-metal bearings have substantially lower wear rates than highly cross-linked polyethylene and wear decreases with head diameter. Bedding in wear is also lower with reduced radial clearance. Differential hardness ceramic-on-metal bearings and the application of ceramic-like coatings reduce metal wear and ion levels.

  18. Discussion: European Commission policy

    International Nuclear Information System (INIS)

    Coldwell, R.

    1993-01-01

    This paper documents the debate which arose following two papers presented to a seminar run by the Centre for the Study of Regulated Industries, on 11th November 1992, on European Commission (EC) energy policies. The issues raised cover how an internal market for electricity and natural gas will be implemented under a proposed EC directive, bearing in mind the level of opposition from a number of Member States. How this Directive will apply to vertically integrated structures, such as Scottish Electricity Industry, is also considered. (UK)

  19. Karst and Caves of the Black Hills, South Dakota, USA; Karst y cuevas de las Black Hills, Dakota del Sur, EE.UU

    Energy Technology Data Exchange (ETDEWEB)

    Palmer, A. N.

    2016-07-01

    The caves of the Black Hills are located in Carboniferous limestone and dolomite of the Madison Formation in western South Dakota. The climate is semi-arid, and surface karst features are few. Entrances to known caves are rather small, and the two largest caves, Wind Cave and Jewel Cave, were discovered only in the late 1880s and in 1900, respectively. Intermittent exploration and mapping have been conducted by local volunteers, National Park Service staff, and the National Speleological Society. Jewel Cave, in Jewel Cave National Monument, contains 290 km of mapped passages; and Wind Cave, in Wind Cave National Park, contains 230 km. They are the third and sixth longest known caves in the world. (Author)

  20. Isotopic investigations of the waters from the Movile Cave - Mangalia area

    International Nuclear Information System (INIS)

    Feurdean, Lucia; Feurdean, Victor

    2001-01-01

    As a conservative tracer in carbonate rocks deuterium was used to determine the unelucidated problems of water origin in the Movile Cave-Mangalia, which is the unique ecosystem from the world based on chemoautotrophic conditions. According to the δD values the water from Movile Cave is meteoric in origin but can not originate from local site. The groundwater from neighboring area of cave has their recharge area at high altitude and considerable distance. δD values of water samples present time variations with a distinct seasonal effect. The seasonal δD values are shifted with a half meteoric cycle vs. normal succession of seasonal maximum and minimum values. Water seems to be originated from the Prebalkan Plateau situated in the south of Dobrogea. The study indicates that the intrusion of water in the karst occurs by conduit flow and hydrostatic pressure. The geometry of conduit controls the movement of the water. The cave and the Karaoban Lake is the discharge area of two main components of groundwater: the first is coming from southwest and has isotope characteristic similar to lower altitude water (500 m) and the second is moving from southeast and has the isotope composition similar to high altitude water (>1000 m). The Movile Cave and Karaoban Lake are connected and the cave water is discharged by overflow mechanism isolating the cave from atmosphere. (authors)

  1. Investigation of tracking systems properties in CAVE-type virtual reality systems

    Science.gov (United States)

    Szymaniak, Magda; Mazikowski, Adam; Meironke, Michał

    2017-08-01

    In recent years, many scientific and industrial centers in the world developed a virtual reality systems or laboratories. One of the most advanced solutions are Immersive 3D Visualization Lab (I3DVL), a CAVE-type (Cave Automatic Virtual Environment) laboratory. It contains two CAVE-type installations: six-screen installation arranged in a form of a cube, and four-screen installation, a simplified version of the previous one. The user feeling of "immersion" and interaction with virtual world depend on many factors, in particular on the accuracy of the tracking system of the user. In this paper properties of the tracking systems applied in I3DVL was investigated. For analysis two parameters were selected: the accuracy of the tracking system and the range of detection of markers by the tracking system in space of the CAVE. Measurements of system accuracy were performed for six-screen installation, equipped with four tracking cameras for three axes: X, Y, Z. Rotation around the Y axis was also analyzed. Measured tracking system shows good linear and rotating accuracy. The biggest issue was the range of the monitoring of markers inside the CAVE. It turned out, that the tracking system lose sight of the markers in the corners of the installation. For comparison, for a simplified version of CAVE (four-screen installation), equipped with eight tracking cameras, this problem was not occur. Obtained results will allow for improvement of cave quality.

  2. In situ acetylene reduction activity of Scytonema julianum in Vapor cave (Spain

    Directory of Open Access Journals (Sweden)

    Asencio Antonia Dolores

    2011-01-01

    Full Text Available Nitrogen fixation was measured in situ for the first time by acetylene reduction for a greyish mat composed of Scytonema julianum in cave- like environments. Mat-specific rates (129.9-215.7 nmol C2 H4 m-2 s-1 for daytime fixation and 65.1-120.6 nmol C2 H4 m-2 s-1 for nighttime fixation recorded in the Vapor cave differed considerably due to the energy reserves stored during photosynthesis being exhausted and used in the dark phase. The most influential environmental parameter for nitrogen fixation in the Vapor cave is temperature in the daytime and nighttime fixations. Nitrogen fixation by cyanobacteria may contribute considerably to the overall nitrogen cycle in harsh environments such as caves. Nitrogenase activity in Scytonema julianum was roughly 30 times higher than that of Scytonema mirabile, which also grew in cave environments, which is due to the characteristics of each site. The entrance of Vapour cave (Spain faces SE, measures 0.75 x 0.6 m and opens to shafts of a total depth of 80 m. Its dimensions and environmental conditions (relative humidity up to 100%; maximum temperature, 43oC imply that it is isolated from external influences, and that the microclimate differs substantially from that experienced externally. Nitrogen fixation, photon flux density, relative humidity and temperature in the Vapor cave were taken hourly over a 24-hour period in winter.

  3. Caving thickness effects of surrounding rocks macro stress shell evolving characteristics

    Institute of Scientific and Technical Information of China (English)

    XIE Guang-xiang; YANG Ke

    2009-01-01

    In order to explore the influence of different caving thicknesses on the MSS dis-tribution and evolving characteristics of surrounding rocks in unsymmetrical disposal and fully mechanized top-coal caving (FMTC), based on unsymmetrical disposal characteris-tics, the analyses of numerical simulation, material simulation and in-situ observation were synthetically applied according to the geological and technical conditions of the 1151(3) working face in Xieqiao Mine. The results show that the stress peak value of the MSS-base and the ratio of MSS-body height to caving thickness are nonlinear and inversely proportional to the caving thickness. The MSS-base width, the MSS-body height, the MSS-base distance to working face wall and the rise distance of MSS-base beside coal pillar are nonlinear and directly proportional to the caving thickness. The characteristics of MSS distribution and its evolving rules of surrounding rocks and the integrated caving thickness effects are obtained. The investigations will provide lots of theoretic references to the surrounding rocks' stability control of the working face and roadway, roadway layout, gas extraction and exploitation, and efficiency of caving, etc.

  4. CaveMan Enterprise version 1.0 Software Validation and Verification.

    Energy Technology Data Exchange (ETDEWEB)

    Hart, David

    2014-10-01

    The U.S. Department of Energy Strategic Petroleum Reserve stores crude oil in caverns solution-mined in salt domes along the Gulf Coast of Louisiana and Texas. The CaveMan software program has been used since the late 1990s as one tool to analyze pressure mea- surements monitored at each cavern. The purpose of this monitoring is to catch potential cavern integrity issues as soon as possible. The CaveMan software was written in Microsoft Visual Basic, and embedded in a Microsoft Excel workbook; this method of running the CaveMan software is no longer sustainable. As such, a new version called CaveMan Enter- prise has been developed. CaveMan Enterprise version 1.0 does not have any changes to the CaveMan numerical models. CaveMan Enterprise represents, instead, a change from desktop-managed work- books to an enterprise framework, moving data management into coordinated databases and porting the numerical modeling codes into the Python programming language. This document provides a report of the code validation and verification testing.

  5. Diversity and role of cave-dwelling hematophagous insects in pathogen transmission in the Afrotropical region.

    Science.gov (United States)

    Obame-Nkoghe, Judicaël; Leroy, Eric-Maurice; Paupy, Christophe

    2017-04-12

    The progressive anthropization of caves for food resources or economic purposes increases human exposure to pathogens that naturally infect cave-dwelling animals. The presence of wild or domestic animals in the immediate surroundings of caves also may contribute to increasing the risk of emergence of such pathogens. Some zoonotic pathogens are transmitted through direct contact, but many others require arthropod vectors, such as blood-feeding insects. In Africa, hematophagous insects often play a key role in the epidemiology of many pathogens; however, their ecology in cave habitats remains poorly known. During the last decades, several investigations carried out in Afrotropical caves suggested the medical and veterinary importance particularly of insect taxa of the Diptera order. Therefore, the role of some of these insects as vectors of pathogens that infect cave-dwelling vertebrates has been studied. The present review summarizes these findings, brings insights into the diversity of cave-dwelling hematophagous Diptera and their involvement in pathogen transmission, and finally discusses new challenges and future research directions.

  6. Unexpected diversity of sandflies (Diptera: Psychodidae) in tourist caves in Northern Thailand.

    Science.gov (United States)

    Sukantamala, Jedsada; Sing, Kong-Wah; Jaturas, Narong; Polseela, Raxsina; Wilson, John-James

    2017-11-01

    Certain species of Phlebotomine sandflies (Diptera: Psychodidae) are vectors of the protozoa which causes leishmaniasis. Sandflies are found breeding in enclosed places like caves. Thailand is a popular tourist destination, including for ecotourism activities like caving, which increases the risk of contact between tourists and sandflies. Surveillance of sandflies is important for monitoring this risk but identification of species based on morphology is challenged by phenotypic plasticity and cryptic diversity. DNA barcodes have been used for the identification of sandflies in Thailand. We collected sandflies using CDC light trap from four tourist caves in Northern Thailand. Female sandflies were provisionally sorted into 13 morphospecies and 19 unidentified specimens. DNA was extracted from the thorax and legs of sandflies and the DNA barcode region of cytochrome c oxidase I mtDNA amplified and sequenced. The specimens were sorted into 22 molecular operational taxonomic units (MOTU) based on the 145 DNA barcodes, which is significantly more than the morphospecies. Several of the taxa thought to be present in multiple caves, based on morphospecies sorting, split into cave-specific MOTU which likely represent cryptic species. Several MOTU reported in an earlier study from Wihan Cave, Thailand, were also found in these caves. This supports the use of DNA barcodes to investigate species diversity of sandflies and their useful role in surveillance of sandflies in Thailand.

  7. Partial tooth gear bearings

    Science.gov (United States)

    Vranish, John M. (Inventor)

    2010-01-01

    A partial gear bearing including an upper half, comprising peak partial teeth, and a lower, or bottom, half, comprising valley partial teeth. The upper half also has an integrated roller section between each of the peak partial teeth with a radius equal to the gear pitch radius of the radially outwardly extending peak partial teeth. Conversely, the lower half has an integrated roller section between each of the valley half teeth with a radius also equal to the gear pitch radius of the peak partial teeth. The valley partial teeth extend radially inwardly from its roller section. The peak and valley partial teeth are exactly out of phase with each other, as are the roller sections of the upper and lower halves. Essentially, the end roller bearing of the typical gear bearing has been integrated into the normal gear tooth pattern.

  8. Local adaptation and pronounced genetic differentiation in an extremophile fish, Poecilia mexicana, inhabiting a Mexican cave with toxic hydrogen sulphide.

    Science.gov (United States)

    Plath, M; Hauswaldt, J S; Moll, K; Tobler, M; García De León, F J; Schlupp, I; Tiedemann, R

    2007-03-01

    We investigated genetic differentiation and migration patterns in a small livebearing fish, Poecilia mexicana, inhabiting a sulfidic Mexican limestone cave (Cueva del Azufre). We examined fish from three different cave chambers, the sulfidic surface creek draining the cave (El Azufre) and a nearby surface creek without the toxic hydrogen sulphide (Arroyo Cristal). Using microsatellite analysis of 10 unlinked loci, we found pronounced genetic differentiation among the three major habitats: Arroyo Cristal, El Azufre and the cave. Genetic differentiation was also found within the cave between different pools. An estimation of first-generation migrants suggests that (i) migration is unidirectional, out of the cave, and (ii) migration among different cave chambers occurs to some extent. We investigated if the pattern of genetic differentiation is also reflected in a morphological trait, eye size. Relatively large eyes were found in surface habitats, small eyes in the anterior cave chambers, and the smallest eyes were detected in the innermost cave chamber (XIII). This pattern shows some congruence with a previously proposed morphocline in eye size. However, our data do not support the proposed mechanism for this morphocline, namely that it would be maintained by migration from both directions into the middle cave chambers. This would have led to an increased variance in eye size in the middle cave chambers, which we did not find. Restricted gene flow between the cave and the surface can be explained by local adaptations to extreme environmental conditions, namely H2S and absence of light. Within the cave system, habitat properties are patchy, and genetic differentiation between cave chambers despite migration could indicate local adaptation at an even smaller scale.

  9. Estimation of deep infiltration in unsaturated limestone environments using cave lidar and drip count data

    Science.gov (United States)

    Mahmud, K.; Mariethoz, G.; Baker, A.; Treble, P. C.; Markowska, M.; McGuire, E.

    2016-01-01

    Limestone aeolianites constitute karstic aquifers covering much of the western and southern Australian coastal fringe. They are a key groundwater resource for a range of industries such as winery and tourism, and provide important ecosystem services such as habitat for stygofauna. Moreover, recharge estimation is important for understanding the water cycle, for contaminant transport, for water management, and for stalagmite-based paleoclimate reconstructions. Caves offer a natural inception point to observe both the long-term groundwater recharge and the preferential movement of water through the unsaturated zone of such limestone. With the availability of automated drip rate logging systems and remote sensing techniques, it is now possible to deploy the combination of these methods for larger-scale studies of infiltration processes within a cave. In this study, we utilize a spatial survey of automated cave drip monitoring in two large chambers of Golgotha Cave, south-western Western Australia (SWWA), with the aim of better understanding infiltration water movement and the relationship between infiltration, stalactite morphology, and unsaturated zone recharge. By applying morphological analysis of ceiling features from Terrestrial LiDAR (T-LiDAR) data, coupled with drip time series and climate data from 2012 to 2014, we demonstrate the nature of the relationships between infiltration through fractures in the limestone and unsaturated zone recharge. Similarities between drip rate time series are interpreted in terms of flow patterns, cave chamber morphology, and lithology. Moreover, we develop a new technique to estimate recharge in large-scale caves, engaging flow classification to determine the cave ceiling area covered by each flow category and drip data for the entire observation period, to calculate the total volume of cave discharge. This new technique can be applied to other cave sites to identify highly focussed areas of recharge and can help to better

  10. A Transcriptomic Analysis of Cave, Surface, and Hybrid Isopod Crustaceans of the Species Asellus aquaticus.

    Directory of Open Access Journals (Sweden)

    Bethany A Stahl

    Full Text Available Cave animals, compared to surface-dwelling relatives, tend to have reduced eyes and pigment, longer appendages, and enhanced mechanosensory structures. Pressing questions include how certain cave-related traits are gained and lost, and if they originate through the same or different genetic programs in independent lineages. An excellent system for exploring these questions is the isopod, Asellus aquaticus. This species includes multiple cave and surface populations that have numerous morphological differences between them. A key feature is that hybrids between cave and surface individuals are viable, which enables genetic crosses and linkage analyses. Here, we advance this system by analyzing single animal transcriptomes of Asellus aquaticus. We use high throughput sequencing of non-normalized cDNA derived from the head of a surface-dwelling male, the head of a cave-dwelling male, the head of a hybrid male (produced by crossing a surface individual with a cave individual, and a pooled sample of surface embryos and hatchlings. Assembling reads from surface and cave head RNA pools yielded an integrated transcriptome comprised of 23,984 contigs. Using this integrated assembly as a reference transcriptome, we aligned reads from surface-, cave- and hybrid- head tissue and pooled surface embryos and hatchlings. Our approach identified 742 SNPs and placed four new candidate genes to an existing linkage map for A. aquaticus. In addition, we examined SNPs for allele-specific expression differences in the hybrid individual. All of these resources will facilitate identification of genes and associated changes responsible for cave adaptation in A. aquaticus and, in concert with analyses of other species, will inform our understanding of the evolutionary processes accompanying adaptation to the subterranean environment.

  11. Evolution of cave Axiokebuita and Speleobregma (Scalibregmatidae, Annelida)

    DEFF Research Database (Denmark)

    Martinez Garcia, Alejandro; Di Domenico, Maikon; Worsaae, Katrine

    2013-01-01

    The evolutionary history of Axiokebuita and Speleobregma, two poorly known lineages of annelids exclusive from deep-sea or marine caves but always from crevicular habitats, is explored here. Speleobregma lanzaroteum Bertelsen, 1986, and Axiokebuita cavernicola sp. n. are described from anchialine...... ciliated palps. Our results support two independent cave colonization events, favoured by the preadaptation of the members of Axiokebuita-Speleobregma lineage to crevicular habitats.......The evolutionary history of Axiokebuita and Speleobregma, two poorly known lineages of annelids exclusive from deep-sea or marine caves but always from crevicular habitats, is explored here. Speleobregma lanzaroteum Bertelsen, 1986, and Axiokebuita cavernicola sp. n. are described from anchialine...

  12. Electronic microscopy and EDX characterization of teotihuacan prehispanic mortar from the cave under the sun pyramid

    Energy Technology Data Exchange (ETDEWEB)

    Martinez, T. [Faculty of Chemistry, National University of Mexico, Building D, CU (O4510) Mexico, D.F. (Mexico)]. E-mail: tmc@servidor.unam.mx; Martinez, G. [Coordinacion Nacional de Conservacion del Patrimonio Cultural. Xicontencatl y General Anaya s/n. (04120) Mexico, D.F. (Mexico); Mendoza, D. [National Institute of Nuclear Research.. Carr. Mexico-Toluca Km 36.5 (52045), Salazar, Ocoyoacac, Edo. de Mexico (Mexico); Juarez, F. [Institute of Geophysics, National University of Mexico, Circuito Institutos, CU (04510) Mexico, D.F. (Mexico); Cabrera, L. [Faculty of Chemistry, National University of Mexico, Building D, CU (O4510) Mexico, D.F. (Mexico)

    2005-12-01

    A cave (102 m long) under the structure of the Sun pyramid of the prehispanic Teotihuacan City indicates the importance of the pyramid. Studies of the cave mortar samples using energy dispersive X-ray (EDX) fluorescence, scanning electron microscopy (SEM) and X-ray diffraction (XRD) showed no difference in the chemical elemental composition. The elements can be distributed in three groups: major, minor and trace elements. The minerals identified were compatible with the origins of the cave and with the magnetic pattern.

  13. Biochemical mechanisms of resistance to p-nitrochlorobenzene of karst caves microorganisms

    Directory of Open Access Journals (Sweden)

    O. S. Suslova

    2015-08-01

    Full Text Available The biochemical mechanisms of resistance to persistent organic xenobiotic p-nitrochlorobenzene (NCB of bacterial strains isolated from two cave clays ecosystems – Mushkarova Yama (Podolia, Ukraine and Kuybyshevskaya (Western Caucasus, Abkhazia have been established. It has been determined that chemoorganotrophic karst caves strains could interact with NCB and transform it reducing the nitro group with formation of p-chloroaniline (ClA followed by further destruction of NCB aromatic ring. This explained high resistance of caves strains to NCB. The studied strains could potentially be used in wastewater treatment from nitrochloraromatic compounds.

  14. Tamarugite in the Steam-Condensate Alteration Paragenesis in Diana Cave (SW Romania)

    Science.gov (United States)

    Puscas, C. M.; Onac, B. P.; Effenberger, H. S.; Povară, I.

    2012-12-01

    The double-salt hydrate tamarugite [NaAl(SO4)2 6H2O] is an uncommon mineral in the cave environment, forming as a result of chemical reactions between water and bedrock only under very specific conditions. The Diana Cave hosts a unique tamarugite occurrence, the first one to be reported from a typical karst environment. The cave is located within the limits of Băile Herculane township in the Cerna Mountains, SW Romania. It consists of a 14 m long, westward-oriented single passage, developed along the Diana Fault. In 1974 a concrete-clad mine gallery was created to channel the thermal water (Diana 1+2 Spring) flowing through the cave to a pumping station. The spring's chemical and physical parameters fluctuated through time, averaging 51.98° C, discharge of 0.96 Ls-1, pH of 7.46, 5768.66 ppm TDS, 9303 μScm-1 conductivity, 5.02 salinity. The major chemical components of the thermo-mineral water in Diana Cave are, Na+ (1392.57 ppm), K+ (58.55 ppm), Ca2+ (725.16 ppm), Mg2+ (10.78 ppm), Cl- (3376.83 ppm), and SO42- (92.27 ppm), and H2S (24.05 ppm), with traces of Si, Fe2+, Br+, I-, and Li+. The general air circulation pattern within the cave is fairly simple: cold air from the outside sweeps into the cave along the floor, heats up at the contact with the thermo-mineral water, ascends, and exists the cave along the ceiling. At the contact with the cold walls of the Diana Cave, the hot steam condenses and gives rise to a rich and exotic sulfate-mineral paragenesis (including halotrichite-series minerals, gypsum, bassanite, anhydrite, epsomite, alunite, halite, native sulfur, etc.). The most exotic minerals precipitate at or below the contact between the Tithonic - Neocomian limestone and the overlaying Cretaceous shaly limestone, as a result of steam-condensate alteration. Minerogenetic mechanisms responsible for the peculiar sulfate mineral assemblage in Diana Cave are evaporation, oxidation, hydrolysis, double exchange reactions, and deposition from vapours or

  15. Magnetically leviated superconducting bearing

    Science.gov (United States)

    Weinberger, Bernard R.; Lynds, Jr., Lahmer

    1993-01-01

    A magnetically levitated superconducting bearing includes a magnet (2) mounted on a shaft (12) that is rotatable around an axis of rotation and a Type II superconductor (6) supported on a stator (14) in proximity to the magnet (2). The superconductor (6) is positioned so that when it is cooled to its superconducting state in the presence of a magnetic field, it interacts with the magnet (2) to produce an attractive force that levitates the magnet (2) and supports a load on the shaft (12). The interaction between the superconductor (6) and magnet(2) also produces surface screening currents (8) that generate a repulsive force perpendicular to the load. The bearing also has means for maintaining the superconductor at a temperature below its critical temperature (16, 18). The bearing could also be constructed so the magnet (2) is supported on the stator (14) and the superconductor (6) is mounted on the shaft (12). The bearing can be operated by cooling the superconductor (6) to its superconducting state in the presence of a magnetic field.

  16. Investigations into stress shell characteristics of surrounding rock in fully mechanized top-coal caving face

    Energy Technology Data Exchange (ETDEWEB)

    Xie, G.X.; Chang, J.C.; Yang, K. [Anhui University of Science and Technology, Huainan (China)

    2009-01-15

    A key issue in underground mining is to understand and master the evolving patterns of stress induced by mining, and to control and utilize the action of rock pressure. Numerical and physical modeling tests have been carried out to investigate the distribution patterns of stress in the rock surrounding a fully mechanized top-coal caving (FMTC) face. The results showed that a macro-stress shell composed of high stress exists in the rock surrounding an FMTC face. The stress of the shell is higher than its internal and external stress and the stresses at its skewback producing abutment pressure for the surrounding rock. The stress shell lies in the virgin coal and rock mass in the vicinity of the face and its sagging zone. The stress shell, which bears and transfers the loads of overlying strata, acts as the primary supporting system of forces, and is the corpus of characterizing three-dimensional and macro-rock pressure distribution of mining face. Its external and internal shape changes with the variations in the working face structure as the face advances. Within the low-stress zone inside the stress shell, another structure, i.e. voussoir beam, which only bears parts of the load from the lower-lying strata, will produce periodic pressures on the face instead of great dynamic pressure even if the beam ruptures and loses stability. The results show that the FMTC face is situated within the lower-stress zone, which is protected by the stress shell of the overlying surrounding rock. We give an explanation of lower occurrence of rock pressure on FMTC faces, and reveal the mechanical nature of the top coal of an FMTC face acting as a 'cushion'. The strata behaviors of the face and its neighboring gates are under control of the stress shell. Drastic rock pressure in mine may occur when the balance of the stress shell is destruction or the forces system of the stress shell transfers. Crown Copyright

  17. Evolution of coprophagy and nutrient absorption in a Cave Salamander

    Directory of Open Access Journals (Sweden)

    Daphne Soares

    2017-11-01

    Full Text Available The transition from carnivory to omnivory is poorly understood. The ability to feed at more than one trophic level theoretically increases an animal’s fitness in a novel environment. Because of the absence of light and photosynthesis, most subterranean ecosystems are characterized by very few trophic levels, such that food scarcity is a challenge in many subterranean habitats. One strategy against starvation is to expand diet breadth. Grotto Salamanders (Eurycea spelaea (Stejneger, 1892 are known to ingest bat guano deliberately, challenging the general understanding that salamanders are strictly carnivorous. Here we tested the hypothesis that grotto salamanders have broadened their diet related to cave adaptation and found that, although coprophagous behavior is present, salamanders are unable to acquire sufficient nutrition from bat guano alone. Our results suggest that the coprophagic behavior has emerged prior to physiological or gut biome adaptations.

  18. Radiocarbon chronology of Manot Cave, Israel and Upper Paleolithic dispersals

    Science.gov (United States)

    Alex, Bridget; Barzilai, Omry; Hershkovitz, Israel; Marder, Ofer; Berna, Francesco; Caracuta, Valentina; Abulafia, Talia; Davis, Lauren; Goder-Goldberger, Mae; Lavi, Ron; Mintz, Eugenia; Regev, Lior; Bar-Yosef Mayer, Daniella; Tejero, José-Miguel; Yeshurun, Reuven; Ayalon, Avner; Bar-Matthews, Mira; Yasur, Gal; Frumkin, Amos; Latimer, Bruce; Hans, Mark G.; Boaretto, Elisabetta

    2017-01-01

    The timing of archeological industries in the Levant is central for understanding the spread of modern humans with Upper Paleolithic traditions. We report a high-resolution radiocarbon chronology for Early Upper Paleolithic industries (Early Ahmarian and Levantine Aurignacian) from the newly excavated site of Manot Cave, Israel. The dates confirm that the Early Ahmarian industry was present by 46,000 calibrated years before the present (cal BP), and the Levantine Aurignacian occurred at least between 38,000 and 34,000 cal BP. This timing is consistent with proposed migrations or technological diffusions between the Near East and Europe. Specifically, the Ahmarian could have led to the development of the Protoaurignacian in Europe, and the Aurignacian in Europe could have spread back to the Near East as the Levantine Aurignacian. PMID:29152566

  19. Application of fractal theory to top-coal caving

    International Nuclear Information System (INIS)

    Xie, H.; Zhou, H.W.

    2008-01-01

    The experiences of underground coal mining in China show that coal in a thick hard coal seam with a hard roof, the so-called 'double hard coal seam', is difficult to be excavated by top-coal caving technique. In order to solve the problem, a top-coal weakening technique is proposed in this paper. In the present study, fractal geometry provides a new description of the fracture mechanism for blasting. By means of theoretical analysis of the relationship between the fractal dimension of blasting fragments and the dynamite specific energy, a mechanical model for describing the size distribution of top-coal and the dissipation of blasting energy is proposed. The theoretical results are in agreement with laboratory and in situ test results. Moreover, it is shown that the fractal dimension of coal fragments can be used as an index for optimizing the blasting parameters for a top-coal weakening technique

  20. Isotopic measurement in ice, Ledenica Cave, Velebit, Croatia

    International Nuclear Information System (INIS)

    Horvatincic, N.

    1996-01-01

    The distribution of radioactive tritium ( 3 H) and stable isotopes of hydrogen ( 2 H/ 1 H) and oxygen ( 18 O/ 16 O) was determined in 45 m long ice deposit found in the Ledenica Cave, Velebit Mt., Croatia. The aim of this work was to determine the influence of the significant radioactive contamination of the atmosphere in sixties to the naturally protected environment. We took ice samples from the ice deposit at each 20 cm from the surface up to 1 m, then at the 3rd, 4th, and 5th m and at the 30th and 40 th m from the surface. The tritium analyses showed the following: The tritium activity at the surface is 1.3 Bq/L, similar as tritium concentration in the recent precipitation in Zagreb area. The maximum tritium activity was measured at the 3th m from the surface, 2.8 Bq/L. It means that the ice layer originated from the time period of 1960-1965 when, because of the thermonuclear weapon tests, the tritium activity of the atmosphere was significantly higher than today. The estimated time period of the ice deposit formation according to the tritium activity distribution and assuming the uniform sedimentation rate of ice, was app. 500 years. This is in good agreement with the 14 C age of ice deposit is 450±100 years. d 18 O and d 2 H values for ice samples range between -6.74 promilles and -10.25 promilles, and -50.3 promilles and -67.9 promilles, respectively. These values indicate the influence mostly of continental climate with dominant part of winter precipitation. A sample of speleothem from the Ledenica Cave was also dated by the 14 C and 230 Th/ 234 U dating methods. The 230 Th/ 234 U age is 301000±55000 years. (author)

  1. First investigations of an ice core from Eisriesenwelt cave (Austria

    Directory of Open Access Journals (Sweden)

    B. May

    2011-02-01

    Full Text Available Investigations into the genesis and dynamical properties of cave ice are essential for assessing the climate significance of these underground glaciers. We drilled an ice core through a 7.1 m-thick ice body filling a large cavern of the dynamic ice cave Eisenriesenwelt (Austria. In addition to visual core inspections, quasi-continuous measurements at 2 cm resolution comprised particulate matter, stable water isotope (δ18O, δD and electrolytic conductivity profiles supplemented by specifically selected samples analyzed for tritium and radiocarbon. We found that recent ablation led to an almost complete loss of bomb-derived tritium removing any ice accumulated since, at least, the early fifties leaving the actual ice surface even below the natural tritium level. The small particulate organic masses rendered radiocarbon dating inconclusive, though a crude estimate gave a basal ice age in the order of several thousand years. The visual stratigraphy and all investigated parameters showed a clear dichotomy between the upper 2 m and the bottom 3 m of the core, which points to a substantial change in the ice formation process. Main features of the core comprise the changing appearance and composition of distinct cryocalcite layers, extremely low total ion content and a surprisingly high variability of the isotope signature. Co-isotope evaluation (δD versus δ18O of the core in comparison with data from precipitation and karst spring water clearly indicate that ice formation is governed by (slow freezing of dripping water.

  2. The physicochemical characterization of cave paintings of Baja California

    International Nuclear Information System (INIS)

    Valdez, B.; Cobo, J.; Schorr, M.; Cota, L.; Oviedo, F.

    2006-01-01

    The Palaeolithic paintings of Baja California constitute an important contribution to the national, historic and cultural patrimony of Mexico. The aim of this investigation was to determine the physicochemical characteristics, the microstructure and texture of these polychrome paintings, painted on rocks encountered in the mountainous, desert/arid zones of Baja California and Baja California South. The first stage of this work was devoted to the examination and recording of the cave paintings of 'El Vallecito', a narrow fluvial valley displaying large granitic rocks emerging from the sandy soil. Tiny painting samples were collected and analyzed by SEM, EDS and FTIR techniques. The painters used four main colours: red, black, yellow and white. The paint raw materials are mineral pigments: white (kaolin, calcite, and gypsum), red (hematite), yellow (ochre, limonite), black (charcoal from burnt wood or calcined bones) and water as a diluent and/or a binder, all encountered in the painters habitat. The minerals were collected, ground and sometimes heated to change their tone. By mixing with water, a spreadable paste or a thick slurry was produced, which was applied with the fingers for lines or a piece of animal skin for figures, respectively. The 100% solids, dry paint converts into a dense, hard layer, incrusted into the grainy, rough, hollow granite rock surface. This paint might be called s tone on stone , explaining its permanence for centuries enduring heat, wind and weather. A simulation of the painting technique was done at the Materials and Corrosion Laboratory, UABC by collecting mineral pigments, preparing the paint as a paste or slurry and applying it on a granitic rock. Knowing the paint composition, production and application techniques will be useful in e conservation and restoration of cave paintings and stone-built, ancient structures such as pyramids, cathedrals and monuments. (Author)

  3. Aspergillus baeticus sp. nov. and Aspergillus thesauricus sp. nov., two species in section Usti from Spanish caves.

    Science.gov (United States)

    Nováková, Alena; Hubka, Vit; Saiz-Jimenez, Cesareo; Kolarik, Miroslav

    2012-11-01

    Two novel species of Aspergillus that are clearly distinct from all known species in section Usti were revealed during a study of microfungal communities in Spanish caves. The novel species identified in this study and additional species of Aspergillus section Usti are associated with places and substrates related to human activities in caves. Novel species are described using data from four loci (ITS, benA, caM and rpb2), morphology and basic chemical and physiological analyses. Members of the species Aspergillus thesauricus sp. nov. were isolated from various substrates, including decaying organic matter, cave air and cave sediment of the Cueva del Tesoro Cave (the Treasure cave); the species is represented by twelve isolates and is most closely related to the recently described Aspergillus germanicus. Members of the species Aspergillus baeticus sp. nov. were isolated from cave sediment in the Gruta de las Maravillas Cave (the Grotto of the Marvels); the species is represented by two isolates. An additional isolate was found in the Cueva del Tesoro Cave and in the Demänovská Peace Cave (Slovakia), suggesting a potentially wide distribution of this micro-organism. The species is related to Aspergillus ustus and Aspergillus pseudoustus. Both species were unable to grow at 37 °C, and a weakly positive, light greenish yellow Ehrlich reaction was observed in A. thesauricus. Unique morphological features alone are sufficient to distinguish both species from related taxa.

  4. Annual and transient signatures of gas exchange and transport in the Castañar de Ibor cave (Spain

    Directory of Open Access Journals (Sweden)

    Fernandez-Cortes A.

    2009-07-01

    Full Text Available The large microclimatic stability is a basic characteristic of the subterranean karst systems and causes a high sensitivity to changesin environmental conditions. High-accuracy monitoring of Castañar de Ibor cave (Spain determined the temporal evolution of theaerodynamic processes and ventilation rate by tracking CO2 and 222Rn levels over a twelve-month period. This cave is characterizedby a very stable microclimate, with high and relatively constant radon content (the mean value is 32200 Bq/m3, roughly, and thestandard deviation is 7600 Bq/m3 and a moderate and quite stable CO2 concentration (the mean value is 3730 ppm and the standarddeviation is 250 ppm. Beside the general patterns of cave microclimate throughout an annual cycle, some particular microclimaticprocesses are described with regard to the gas exchange between the cave and the outside atmosphere. There is a complexmicroclimatic functional relationship between the meteorological and cave microclimate conditions and the diffusion and flow of tracergases from the fractures and the pore system of soil and host rock to cave atmosphere. Transient variations of tracer gas on cave airare controlled by natural barometric fluxes and anthropogenic forced ventilation due to uncontrolled opening of cave entrance. Theshort-term fluctuations of gas levels on cave air reveal distinct patterns during the exhalation process of theses gases from the netof fissures and pores to the cave atmosphere, depending on the isolation effect of soil and host rock.

  5. European communion

    DEFF Research Database (Denmark)

    Manners, Ian James

    2013-01-01

    Political theory of European union, through an engagement between political concepts and theoretical understandings, provides a means of identifying the EU as a political object. It is argued that understanding the projects, processes and products of European union, based on ‘sharing’ or ‘communion......’, provides a better means of perceiving the EU as a political object rather than terms such as ‘integration’ or ‘co-operation’. The concept of ‘European communion’ is defined as the ‘subjective sharing of relationships’, understood as the extent to which individuals or groups believe themselves to be sharing...... relations (or not), and the consequences of these beliefs for European political projects, processes and products. By exploring European communion through an engagement with contemporary political theory, using very brief illustrations from the Treaty of Lisbon, the article also suggests that European...

  6. The Unicorn Cave, Southern Harz Mountains, Germany: From known passages to unknown extensions with the help of geophysical surveys

    Science.gov (United States)

    Kaufmann, Georg; Nielbock, Ralf; Romanov, Douchko

    2015-12-01

    In soluble rocks (limestone, dolomite, anhydrite, gypsum, …), fissures and bedding partings can be enlarged with time by both physical and chemical dissolution of the host rock. With time, larger cavities evolve, and a network of cave passages can evolve. If the enlarged cave voids are not too deep under the surface, geophysical measurements can be used to detect, identify and trace these karst structures, e.g.: (i) gravity revealing air- and sediment-filled cave voids through negative Bouguer anomalies, (ii) electrical resistivity imaging (ERI) mapping different infillings of cavities either as high resistivities from air-filled voids or dry soft sediments, or low resistivities from saturated sediments, and (iii) groundwater flow through electrical potential differences (SP) arising from dislocated ionic charges from the walls of the underground flow paths. We have used gravity, ERI, and SP methods both in and above the Unicorn Cave located in the southern Harz Mountains in Germany. The Unicorn Cave is a show cave developed in the Werra dolomite formation of the Permian Zechstein sequence, characterised by large trunk passages interrupted by larger rooms. The overburden of the cave is only around 15 m, and passages are filled with sediments reaching infill thicknesses up to 40 m. We present results from our geophysical surveys above the known cave and its northern and southern extension, and from the cave interior. We identify the cave geometry and its infill from gravity and ERI measurements, predict previously unknown parts of the cave, and subsequently confirm the existence of these new passages through drilling. From the wealth of geophysical data acquired we derive a three-dimensional structural model of the Unicorn Cave and its surrounding, especially the cave infill.

  7. Using the CAVE virtual-reality environment as an aid to 3-D electromagnetic field computation

    International Nuclear Information System (INIS)

    Turner, L.R.; Levine, D.; Huang, M.; Papka, M.

    1995-01-01

    One of the major problems in three-dimensional (3-D) field computation is visualizing the resulting 3-D field distributions. A virtual-reality environment, such as the CAVE, (CAVE Automatic Virtual Environment) is helping to overcome this problem, thus making the results of computation more usable for designers and users of magnets and other electromagnetic devices. As a demonstration of the capabilities of the CAVE, the elliptical multipole wiggler (EMW), an insertion device being designed for the Advanced Photon Source (APS) now being commissioned at Argonne National Laboratory (ANL), wa made visible, along with its fields and beam orbits. Other uses of the CAVE in preprocessing and postprocessing computation for electromagnetic applications are also discussed

  8. Bermuda Deep Water Caves 2011: Dives of Discovery between 20110607 and 20110627

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — During the three week NOAA Ocean Exploration project, Bermuda Deep Water Caves 2011: Dives of Discovery, our four member deep team, aided by numerous assistants,...

  9. Evaluating visual discomfort in stereoscopic projection-based CAVE system with a close viewing distance

    Science.gov (United States)

    Song, Weitao; Weng, Dongdong; Feng, Dan; Li, Yuqian; Liu, Yue; Wang, Yongtian

    2015-05-01

    As one of popular immersive Virtual Reality (VR) systems, stereoscopic cave automatic virtual environment (CAVE) system is typically consisted of 4 to 6 3m-by-3m sides of a room made of rear-projected screens. While many endeavors have been made to reduce the size of the projection-based CAVE system, the issue of asthenopia caused by lengthy exposure to stereoscopic images in such CAVE with a close viewing distance was seldom tangled. In this paper, we propose a light-weighted approach which utilizes a convex eyepiece to reduce visual discomfort induced by stereoscopic vision. An empirical experiment was conducted to examine the feasibility of convex eyepiece in a large depth of field (DOF) at close viewing distance both objectively and subjectively. The result shows the positive effects of convex eyepiece on the relief of eyestrain.

  10. Reassessing Coxcatlan Cave and the early history of domesticated plants in Mesoamerica.

    Science.gov (United States)

    Smith, Bruce D

    2005-07-05

    Reanalysis and direct accelerator mass spectrometry radiocarbon dating of the cucurbit assemblage from Coxcatlan Cave provide information on the timing and sequence of the initial appearance of three domesticated plants in the Tehuacán Valley (Puebla, Mexico) and allow reassessment of the overall temporal context of plant domestication in Mexico. Cucurbita pepo is the earliest documented domesticate in the cave, dating to 7,920 calibrated calendrical (cal) years B.P. The bottle gourd (Lagenaria siceraria) is dated at 7,200 cal years B.P. Cucurbita argyrosperma does not appear until 2,065 cal years B.P. The earlier identification of Cucurbita moschata specimens is not confirmed. Seventy-one radiocarbon dates, including 23 accelerator mass spectrometry dates on cucurbits, provide ample evidence of postdepositional vertical displacement of organic materials in the western half of Coxcatlan Cave, but they also indicate that the eastern half of the cave was largely undisturbed.

  11. Cave Holography – Out of the lab and under the ground

    International Nuclear Information System (INIS)

    Klayer, J

    2013-01-01

    This paper describes the combination of my hobbies, caving and holography. Most traditional holography involves bringing the objects to a lab with all the necessary holography equipment mounted on a stable table. I instead bring all the equipment assembled as a portable unit to the natural formations in a cave with the cave itself being the stable table. The first successes were Denisyuks made with a HeNe or laser diode and spatial filter mounted on a tripod. For greater depth, transmission holograms were made with a DPSS laser in several configurations sometimes using fiber optics to route the reference beam and sometimes a spatial filter and mirrors. The cave environment presents unique obstacles that have been overcome as evidenced by the beautiful holograms made.

  12. Three new cave-dwelling trechine ground beetles from eastern and southeastern Serbia (Coleoptera: Carabidae: Trechinae

    Directory of Open Access Journals (Sweden)

    Ćurčić S.B.

    2014-01-01

    Full Text Available Three new troglobitic trechine ground beetle species are described from three caves in eastern and southeastern Serbia: Duvalius (Paraduvalius bogovinae sp. n., from the Bogovinska Pećina Cave, village of Bogovina, Kučajske Planine Mts., near Boljevac, eastern Serbia; D. (P. milutini sp. n., from the Samar cave system, village of Kopajkošara, Mt. Kalafat, near Svrljig, southeastern Serbia, and D. (P. beljanicae sp. n., from the Velika Atula Cave, village of Strmosten, Mt. Beljanica, near Despotovac, eastern Serbia. The new species are easily distinguished from relatives. All important morphological features, along with the diagnoses and illustrations of the new taxa are presented. The new species are relicts and endemics of eastern and southeastern Serbia. They probably belong to old phyletic lineages of Tertiary or even pre-Tertiary origin. [Projekat Ministarstva nauke Republike Srbije, br. 173038

  13. Microwhip scorpions (Palpigradi) feed on heterotrophic cyanobacteria in Slovak caves - a curiosity among Arachnida

    Czech Academy of Sciences Publication Activity Database

    Smrž, J.; Kováč, L.; Mikeš, J.; Lukešová, Alena

    2013-01-01

    Roč. 8, č. 10 (2013), e75989 E-ISSN 1932-6203 Institutional support: RVO:60077344 Keywords : microwhip scorpions * heterotrophic cyanobacteria * Slovak caves Subject RIV: EG - Zoology Impact factor: 3.534, year: 2013

  14. 43 CFR 37.11 - Nomination, evaluation, and designation of significant caves.

    Science.gov (United States)

    2010-10-01

    ... disturbance or impact; or, the length, volume, total depth, pit depth, height, or similar measurements are... provision in § 37.12 of this part. (g) Decision final. Decisions to designate or not designate a cave as...

  15. Engineering geologic conditions at the sinkhole entrance to Logan Cave, Benton County, Arkansas

    Science.gov (United States)

    Schulz, William H.; McKenna, Jonathan P.

    2004-01-01

    Logan Cave, located in Benton County, Arkansas, is inhabited by several endangered and threatened species. The cave and surrounding area was designated a National Wildlife Refuge under the control of the U.S. Fish and Wildlife Service (USFWS) in 1989. Cave researchers access the cave through a steep-sided sinkhole entrance, which also is one of the two access points used by endangered bats. There is evidence of instability of one of the entrance slopes that has raised concerns that the entrance could close if slope failure was to occur. At the request of USFWS, we performed an engineering geologic investigation of the sinkhole to evaluate stability of this slope, which is comprised of soil, and other mechanisms of sediment transport into the cave entrance. The investigation included engineering geologic mapping, sampling and laboratory testing of subsurface geologic materials, and slope-stability analysis. We found that the sinkhole slope that extends into the entrance of the cave is comprised of sandy and gravelly soil to the depths explored (6.4 meters). This soil likely was deposited as alluvium within a previous, larger sinkhole. Based on properties of the alluvium, geometry of the slope, and results of finite-element slope-stability analyses, we conclude that the slope is marginally stable. Future failures of the slope probably would be relatively thin and small, thus several would be required to completely close the cave entrance. However, sediment is accumulating within the cave entrance due to foot traffic of those accessing the cave, surface-water erosion and transport, and shallow slope failures from the other sinkhole slopes. We conclude that the entrance will be closed by sediment in the future, similar to another entrance that we identified that completely closed in the past. Several measures could be taken to reduce the potential for closure of the cave entrance, including periodic sediment removal, installation of materials that reduce erosion by

  16. Climatic control on the growth of gigantic gypsum crystals within hypogenic caves (Naica mine, Mexico)?

    Science.gov (United States)

    Garofalo, Paolo S.; Fricker, Mattias B.; Günther, Detlef; Forti, Paolo; Mercuri, Anna-Maria; Loreti, Mara; Capaccioni, Bruno

    2010-01-01

    Three hypogenic caves within the Naica mine of Mexico ( Cueva de los Cristales — CLC, Ojo de la Reina — OR, and Cueva de las Velas — CLV) host spectacular gypsum crystals up to 11 m in length. These caves are close to another shallow cave of the area ( Cueva de las Espadas — CLE), with which they cover a 160 m-deep vertical section of the local drainage basin. Similar to other hypogenic caves, all these caves lack a direct connection with the land surface and should be unrelated with climate. A record of multi-technique fluid inclusion data and pollen spectra from cave and mine gypsum indicates surprisingly that climatic changes occurring at Naica could have controlled fluid composition in these caves, and hence crystal growth. Microthermometry and LA-ICP-Mass Spectrometry of fluid inclusions indicate that the shallow, chemically peculiar, saline fluid (up to 7.7 eq. wt.%NaCl) of CLE could have formed from evaporation, during a dry and hot climatic period. The fluid of the deep caves was instead of low salinity (˜ 3.5 eq. wt.% NaCl) and chemically homogeneous, and was poorly affected by evaporation. We propose that mixing of these two fluids, generated at different depths of the Naica drainage basin, determined the stable supersaturation conditions for the gigantic gypsum crystals to grow. Fluid mixing was controlled by the hydraulic communication between CLE and the other deep caves, and must have taken place during cycles of warm-dry and fresh-wet climatic periods, which are known to have occurred in the region. Pollen grains from a 35 ka-old gypsum crystal of CLC corresponds to a fairly homogenous catchment basin made of a mixed broadleaf wet forest, which suggests precipitation during a fresh-wet climatic period and confirms our interpretation of the fluid inclusion data. The unusual combination of geological and geochemical factors of Naica suggests that other hypogenic caves found elsewhere may not host similar crystals. However, this work shows that

  17. Recreational Impacts on the Microclimate of the Gorilla Limestone Cave in Shoushan National Nature Park of Taiwan

    Science.gov (United States)

    Chen, Chun; Ho, Lih-Der

    2017-04-01

    This study reports a continuous microclimate monitoring carried out in the Gorilla Cave (Kaohsiung, Taiwan) between December 2015 and December 2016. This limestone cave is located in the Mt. Shoushan, which is mainly composed of limestone and mudstone. This study tried to assess the recreational impacts to the microclimate of the cave by monitoring the CO2, temperature, humidity and barometric pressure. Two monitoring stations were set up respectively at the front part (station A) and the end of the cave (station B). We also set up an auto-operated time-lapse camera at the entrance of the cave to record the numbers of tourists, and their entering time and the durations in cave. As carbon dioxide in the limestone cave may have negative impact to both speleothems and visitors, our presentation focuses on the variations of CO2 concentration in the Gorilla Cave. Daily and seasonal fluctuations of CO2 concentration were observed. The fluctuations are closely related with the temperature outside the cave. In summer, when the temperature outside the cave maintained at 30。C, fluctuations of CO2 concentration in the cave will become chaotic. The CO2 concentration would fluctuate around 1000ppm most of the day, but it would be relatively low ( 500ppm) during the noon. In winter, when temperature outside the cave maintained below 25゜C, the fluctuation of CO2 concentration in cave presented a steady state ( 400-500 ppm). Only at the noon, the temperature outside the cave rose above 25 ゜C, the CO2 concentration inside the cave would increase. There were 1,517 tourists entered the cave during the monitoring period. The average number of visitors in a group is 13, and each group averagely stayed for 15 minutes. Over half of the visitors (776 tourists) entered the cave in December, due to lower humidity, drier in the cave and less dripping water in winter. After tourists entered the cave, the CO2 concentration value of station A rose instantly. However, most tourists stayed

  18. The present day genesis and evolution of cave minerals inside the Ojo de la Reina Cave (Naica Mine, Mexico

    Directory of Open Access Journals (Sweden)

    Badino Giovanni

    2011-07-01

    Full Text Available Ojo de la Reina is the first and the smallest cave intersected at the -290 level in the Naica Mine (Mexico, therefore it was the firstcavity in which the lowering of temperature induced by mine ventilation caused condensation over crystals’ surface since 2005. Theconsequent dissolution of the gypsum crystals and subsequent condensed water evaporation lead to the deposition of several newminerals, among which some highly soluble Mg/Na compounds (bloedite, epsomite, halite, hexahydrite, kieserite, starkeyite. Thesingle available source of Mg and Na ions in this minerogenetic environment is represented by the huge fluid inclusions widespreadwithin the crystals. The condensation occurs mainly along the widened principal exfoliation (010 planes, and allows to an easy andfast opening of the fluid inclusions that consequently drip Mg-rich fluids stored inside them. Finally the evaporation of the relativelysmall volumes of involved water allows to the development of the high soluble Mg and Na compounds.

  19. Effects of Active Exploration and Passive Observation on Spatial Learning in a CAVE

    OpenAIRE

    Melanson, Brian; Kelso, John; Bowman, Doug A.

    2002-01-01

    This experiment was a modification of Paul N. Wilson's 1999 study entitled "Active Exploration of a Virtual Environment Does Not Promote Orientation or Memory for Objects." It was hoped that changing the immersion level from a standard desktop monitor to a more immersive CAVE environment would change the results of this experiment. All subjects explored a three-dimensional virtual environment in a CAVE. Active subjects were given controls to choose their own path and explore th...

  20. Longwall top coal caving (LTCC) mining technologies with roof softening by hydraulic fracturing method

    Science.gov (United States)

    Klishin, V.; Nikitenko, S.; Opruk, G.

    2018-05-01

    The paper discusses advanced top coal caving technologies for thick coal seams and addresses some issues of incomplete coal extraction, which can result in the environmental damage, landscape change, air and water pollution and endogenous fires. The authors put forward a fundamentally new, having no equivalent and ecology-friendly method to difficult-to-cave roof coal – directional hydraulic fracturing and nonexplosive disintegration.

  1. Phlebotomines (Diptera, Psychodidae in caves of the Serra da Bodoquena, Mato Grosso do Sul State, Brazil

    Directory of Open Access Journals (Sweden)

    Eunice A. B. Galati

    2003-01-01

    Full Text Available The present paper deals with the phlebotomine species captured during the period from January 1998 to June 2000 in 12 caves located in the Serra da Bodoquena, situated in the south central region of Mato Grosso do Sul State, Brazil. Three of the caves are situated further north (in Bodoquena county, seven in the central area (Bonito county and two in the south (Jardim county. These last two caves and three of those in Bonito are located at the west side of the ridge. Eighteen species of phlebotomines were captured within the caves: Brumptomyia avellari (Costa Lima, 1932, Brumptomyia brumpti (Larrousse, 1920, Brumptomyia cunhai (Mangabeira, 1942, Brumptomyia galindoi (Fairchild & Hertig, 1947, Evandromyia corumbaensis (Galati, Nunes, Oshiro & Rego, 1989, Lutzomyia almerioi Galati & Nunes, 1999, Lutzomyia longipalpis (Lutz & Neiva, 1912, Martinsmyia oliveirai (Martins, Falcão & Silva, 1970, Micropygomyia acanthopharynx (Martins, Falcão & Silva, 1962, Micropygomyia peresi (Mangabeira, 1942, Micropygomyia quinquefer (Dyar, 1929, Nyssomyia whitmani (Antunes & Coutinho, 1939, Psathyromyia campograndensis (Oliveira, Andrade-Filho, Falcão & Brazil, 2001, Psathyromyia punctigeniculata (Floch & Abonnenc, 1944, Psathyromyia shannoni (Dyar, 1929, Pintomyia kuscheli (Le Pont, Martinez, Torrez-Espejo & Dujardin, 1998, Sciopemyia sordellii (Shannon & Del Ponte, 1927 and Sciopemyia sp. A total of 29,599 phlebotomine sandflies was obtained. Lutzomyia almerioi was absolutely predominant (91.5% over the other species on both sides of the Bodoquena ridge, with the exception of the southern caves in which it was absent. It presents summer predominance, with nocturnal and diurnal activities. The species breeds in the caves and was captured during daytime both in the dark area and in the mouth of the caves. Martinsmyia oliveirai, the second most frequent sandfly, also presents a summer peak and only predominated over the other species in one cave, in which there

  2. Marine Caves of the Mediterranean Sea: A Sponge Biodiversity Reservoir within a Biodiversity Hotspot

    Science.gov (United States)

    Gerovasileiou, Vasilis; Voultsiadou, Eleni

    2012-01-01

    Marine caves are widely acknowledged for their unique biodiversity and constitute a typical feature of the Mediterranean coastline. Herein an attempt was made to evaluate the ecological significance of this particular ecosystem in the Mediterranean Sea, which is considered a biodiversity hotspot. This was accomplished by using Porifera, which dominate the rocky sublittoral substrata, as a reference group in a meta-analytical approach, combining primary research data from the Aegean Sea (eastern Mediterranean) with data derived from the literature. In total 311 species from all poriferan classes were recorded, representing 45.7% of the Mediterranean Porifera. Demospongiae and Homoscleromorpha are highly represented in marine caves at the family (88%), generic (70%), and species level (47.5%), the latter being the most favored group along with Dictyoceratida and Lithistida. Several rare and cave-exclusive species were reported from only one or few caves, indicating the fragmentation and peculiarity of this unique ecosystem. Species richness and phylogenetic diversity varied among Mediterranean areas; the former was positively correlated with research effort, being higher in the northern Mediterranean, while the latter was generally higher in caves than in the overall sponge assemblages of each area. Resemblance analysis among areas revealed that cavernicolous sponge assemblages followed a pattern quite similar to that of the overall Mediterranean assemblages. The same pattern was exhibited by the zoogeographic affinities of cave sponges: species with Atlanto-Mediterranean distribution and Mediterranean endemics prevailed (more than 40% each), 70% of them having warm-water affinities, since most caves were studied in shallow waters. According to our findings, Mediterranean marine caves appear to be important sponge biodiversity reservoirs of high representativeness and great scientific interest, deserving further detailed study and protection. PMID:22808070

  3. Application of combined shrinkage stoping and pillarless sublevel caving mining method to a uranium deposit

    International Nuclear Information System (INIS)

    Fan Changjun

    2012-01-01

    Pillarless sublevel caving mining method was used to mining ores in a uranium mine. Because ore-rock interface changed greatly, this part of ores can not be recovered effectively in the mining process, resulting in the permanent loss of these ores. Aimed at the problem, a combined shrinkage stoping and pillarless sublevel caving mining method is presented. Practices show that the ore recovery is increased, dilution rate is declined, and mining safety is improved greatly by using the combined method. (authors)

  4. Hydrothermal phenomena in Risovaca cave and within Vencac massif Shumadies, Serbia

    Directory of Open Access Journals (Sweden)

    Wrzak-Tomić Janina

    2004-01-01

    Full Text Available In the Risovaca cave are found, for the karst, atypical alteration in the limestones structure. Also, morphogenesis of the object can not be logically interpret. Those differences are result of hydrothermal process in initial phase of karstic cycle. And then activity of hot water and hot emanations brought up to the metasomatism and destruction of rock, enormous excrete of ornaments and later, ceiling collapse and fill up of cave room.

  5. Predicting the Occurrence of Cave-Inhabiting Fauna Based on Features of the Earth Surface Environment.

    Science.gov (United States)

    Christman, Mary C; Doctor, Daniel H; Niemiller, Matthew L; Weary, David J; Young, John A; Zigler, Kirk S; Culver, David C

    2016-01-01

    One of the most challenging fauna to study in situ is the obligate cave fauna because of the difficulty of sampling. Cave-limited species display patchy and restricted distributions, but it is often unclear whether the observed distribution is a sampling artifact or a true restriction in range. Further, the drivers of the distribution could be local environmental conditions, such as cave humidity, or they could be associated with surface features that are surrogates for cave conditions. If surface features can be used to predict the distribution of important cave taxa, then conservation management is more easily obtained. We examined the hypothesis that the presence of major faunal groups of cave obligate species could be predicted based on features of the earth surface. Georeferenced records of cave obligate amphipods, crayfish, fish, isopods, beetles, millipedes, pseudoscorpions, spiders, and springtails within the area of Appalachian Landscape Conservation Cooperative in the eastern United States (Illinois to Virginia and New York to Alabama) were assigned to 20 x 20 km grid cells. Habitat suitability for these faunal groups was modeled using logistic regression with twenty predictor variables within each grid cell, such as percent karst, soil features, temperature, precipitation, and elevation. Models successfully predicted the presence of a group greater than 65% of the time (mean = 88%) for the presence of single grid cell endemics, and for all faunal groups except pseudoscorpions. The most common predictor variables were latitude, percent karst, and the standard deviation of the Topographic Position Index (TPI), a measure of landscape rugosity within each grid cell. The overall success of these models points to a number of important connections between the surface and cave environments, and some of these, especially soil features and topographic variability, suggest new research directions. These models should prove to be useful tools in predicting the

  6. Behavioral response of cave and surface Asellus aquaticus to water current

    OpenAIRE

    Dacar, Maja

    2017-01-01

    There are many questions regarding what influences the emergence of new species. Firstly and above all, is the appearance of differences within a certain specie, where a certain part is isolated from the group and continues its own evolution. One of these differences appear between the surface- and cave-dwelling Asellus aquaticus, as the ability to hold on to their surface. The discovery of these differences was carried out using a method of experiment, namely on the cave-dwelling Asellus ...

  7. Underground cosmic-ray measurement for morphological reconstruction of the ''Grotta Gigante'' natural cave

    International Nuclear Information System (INIS)

    Caffau, E.; Coren, F.; Giannini, G.

    1997-01-01

    Measurement of the muon flux as a function of direction inside the Grotta Gigante natural cave near Trieste (Italy) was carried out using a tracking apparatus. The measured flux, depending in a well established way on the zenith angle and the rock mass crossed by the muons, allowed the determination of the shape of the cave vault which could be compared with that known from topography and related to the available microgravimetric data of the area. (orig.)

  8. Quaternary faulting in the Tatra Mountains, evidence from cave morphology and fault-slip analysis

    OpenAIRE

    Szczygieł Jacek

    2015-01-01

    Tectonically deformed cave passages in the Tatra Mts (Central Western Carpathians) indicate some fault activity during the Quaternary. Displacements occur in the youngest passages of the caves indicating (based on previous U-series dating of speleothems) an Eemian or younger age for those faults, and so one tectonic stage. On the basis of stress analysis and geomorphological observations, two different mechanisms are proposed as responsible for the development of these displacements. The firs...

  9. Actuators for Active Magnetic Bearings

    Directory of Open Access Journals (Sweden)

    Eric H. Maslen

    2017-10-01

    Full Text Available The literature of active magnetic bearing (AMB technology dates back to at least 1937 when the earliest work that clearly describes an active magnetic bearing system was published by Jesse Beams [...

  10. The paradigm of grizzly bear restoration in North America

    Science.gov (United States)

    Schwartz, C. C.; Maehr, David S.; Noss, Reed F.; Larkin, J.L.

    2002-01-01

    Grizzly bear restoration and recovery is a controversial, highly politicized process. By 1959, when the Craigheads began their pioneering work on Yellowstone grizzly bears, the species had been reduced to a remnant of its historic range. Prior to the colonization of North America by Europeans, the grizzly lived in relatively pristine habitats with aboriginal Native Americans. As civilization expanded, humans changed the face of the landscape, converting grizzly bear habitat to farms and ranches. People killed grizzlies to protect livestock and eliminate a perceived threat to human safety. In concert, habitat loss and direct human-caused mortality had effectively eliminated the grizzly from 95 percent of its historic range in the conterminous United States by the 1920s (Servheen 1989). Grizzly bear numbers had been reduced nearly 98 percent by 1975 when the species was listed as threatened under the Endangered Species Act (ESA) (USFWS 1993).

  11. Lead-free bearing alloys for engine applications

    Science.gov (United States)

    Ratke, Lorenz; Ågren, John; Ludwig, Andreas; Tonn, Babette; Gránásy, László; Mathiesen, Ragnvald; Arnberg, Lars; Anger, Gerd; Reifenhäuser, Bernd; Lauer, Michael; Garen, Rune; Gust, Edgar

    2005-10-01

    Recent developments to reduce the fuel consumption, emission and air pollution, size and weight of engines for automotive, truck, ship propulsion and electrical power generation lead to temperature and load conditions within the engines that cannot be borne by conventional bearings. Presently, only costly multilayer bearings with electroplated or sputtered surface coatings can cope with the load/speed combinations required. Ecological considerations in recent years led to a ban by the European Commission on the use of lead in cars a problem for the standard bronze-lead bearing material. This MAP project is therefore developing an aluminium-based lead-free bearing material with sufficient hardness, wear and friction properties and good corrosion resistance. Only alloys made of components immiscible in the molten state can meet the demanding requirements. Space experimentation plays a crucial role in optimising the cast microstructure for such applications.

  12. Monitoring of radon gas in caves of the Yorkshire Dales, United Kingdom

    International Nuclear Information System (INIS)

    Langridge, D; Stokes, R P; Jackson, C P

    2010-01-01

    A number of vocational training courses are held in caves in the Yorkshire Dales region of the United Kingdom. The instructors and students involved in these courses have the potential to be exposed to enhanced levels of radon ( 222 Rn) and its progeny as a result of their occupations. A prior radiological risk assessment for the training courses recommended that an environmental monitoring programme be carried out to establish the radon concentrations in the caves, and that the caving instructors wear personal radon dosemeters. Radon gas concentrations varied seasonally, being at their highest in summer and their lowest in winter. The lowest result was 40 Bq m -3 recorded in Lower Longchurn cave during winter, whilst the highest result was 4440 Bq m -3 recorded in Crackpot cave during the summer. As the individuals involved in the caving are entering atmospheres with radon gas concentrations in excess of 400 Bq m -3 , the Ionising Radiation Regulations 1999 (GB Parliament 2000 Ionising Radiations Regulations 1999 (London: Stationary Office) SI 1999/3232) apply. A system of work is therefore in place to control exposure to radon. This system of work stipulates an initial dose investigation level of 1 mSv, a second dose investigation level of 2 mSv and an annual dose limit of 6 mSv. The highest annual dose recorded to date is 2.2 mSv, although the average (median) annual dose is only 0.5 mSv.

  13. Cave-dwelling bats (Mammalia: Chiroptera and conservation concerns in South central Mindanao, Philippines

    Directory of Open Access Journals (Sweden)

    Krizler C. Tanalgo

    2015-12-01

    Full Text Available The stable microclimate in caves provides a relatively constant habitat for many bat species in the Philippines, but human encroachment continues to disrupt this habitat and imperil many of the species roosting in the caves.  In South central Mindanao, the diversity and conservation status of cave bats remain undocumented and unexplored.  We employed mist-netting to capture bats from five different caves within the town of Kabacan, northern Cotabato, Philippines.  A total of 14 bat species were identified including the Philippine endemics Hipposideros pygmaeus and Ptenochirus jagori and the threatened Megaerops wetmorei. However, despite the declining conservation status of the bats, local disturbance such as bat hunting for bush meat and unregulated tourism are currently taking place in the caves.  Large species such as Eonycteris spelaea and Rousettus amplexicaudatus are killed almost every day for food and trade.  Therefore, the high species richness, and the presence of endemic and threatened species coupled with the occurrence of anthropogenic disturbances in caves suggests the need for an urgent and effective conservation intervention involving the local government and public community. 

  14. Potential collapse due to geological structures influence in Seropan Cave, Gunung Kidul, Yogyakarta, Indonesia

    Science.gov (United States)

    Nugroho, B.; Pranantya, P. A.; Witjahjati, R.; Rofinus

    2018-01-01

    This study aims to estimate the potential collapse in the Seropan cave, based on the existing geological structure conditions in the cave. This is very necessary because in the Seropan cave will be built Microhydro installation for power plants. The electricity will be used to raise the underground river water in the cave to a barren soil surface, which can be used for surface irrigation. The method used is analysis the quality of rock mass along the cave. Analysis of rock mass quality using Geomechanical Classification or Rock Mass Rating (RMR), to determine the magnitude of the effect of geological structure on rock mass stability. The research path is divided into several sections and quality analysis is performed on each section. The results show that the influence of geological structure is very large and along the cave where the research there are several places that have the potential to collapse, so need to get serious attention in handling it. Nevertheless, the construction of this Microhydro installation can still be carried out by making a reinforcement on potentially collapsing parts

  15. Modeling of luminance distribution in CAVE-type virtual reality systems

    Science.gov (United States)

    Meironke, Michał; Mazikowski, Adam

    2017-08-01

    At present, one of the most advanced virtual reality systems are CAVE-type (Cave Automatic Virtual Environment) installations. Such systems are usually consisted of four, five or six projection screens and in case of six screens arranged in form of a cube. Providing the user with a high level of immersion feeling in such systems is largely dependent of optical properties of the system. The modeling of physical phenomena plays nowadays a huge role in the most fields of science and technology. It allows to simulate work of device without a need to make any changes in the physical constructions. In this paper distribution of luminance in CAVE-type virtual reality systems were modelled. Calculations were performed for the model of 6-walled CAVE-type installation, based on Immersive 3D Visualization Laboratory, situated at the Faculty of Electronics, Telecommunications and Informatics at the Gdańsk University of Technology. Tests have been carried out for two different scattering distribution of the screen material in order to check how these characteristicinfluence on the luminance distribution of the whole CAVE. The basis assumption and simplification of modeled CAVE-type installation and results were presented. The brief discussion about the results and usefulness of developed model were also carried out.

  16. Microhabitat use, population densities, and size distributions of sulfur cave-dwelling Poecilia mexicana.

    Science.gov (United States)

    Jourdan, Jonas; Bierbach, David; Riesch, Rüdiger; Schießl, Angela; Wigh, Adriana; Arias-Rodriguez, Lenin; Indy, Jeane Rimber; Klaus, Sebastian; Zimmer, Claudia; Plath, Martin

    2014-01-01

    The Cueva del Azufre in Tabasco, Mexico, is a nutrient-rich cave and its inhabitants need to cope with high levels of dissolved hydrogen sulfide and extreme hypoxia. One of the successful colonizers of this cave is the poeciliid fish Poecilia mexicana, which has received considerable attention as a model organism to examine evolutionary adaptations to extreme environmental conditions. Nonetheless, basic ecological data on the endemic cave molly population are still missing; here we aim to provide data on population densities, size class compositions and use of different microhabitats. We found high overall densities in the cave and highest densities at the middle part of the cave with more than 200 individuals per square meter. These sites have lower H2S concentrations compared to the inner parts where most large sulfide sources are located, but they are annually exposed to a religious harvesting ceremony of local Zoque people called La Pesca. We found a marked shift in size/age compositions towards an overabundance of smaller, juvenile fish at those sites. We discuss these findings in relation to several environmental gradients within the cave (i.e., differences in toxicity and lighting conditions), but we also tentatively argue that the annual fish harvest during a religious ceremony (La Pesca) locally diminishes competition (and possibly, cannibalism by large adults), which is followed by a phase of overcompensation of fish densities.

  17. Meckel's cave access: anatomic study comparing the endoscopic transantral and endonasal approaches.

    Science.gov (United States)

    Van Rompaey, Jason; Suruliraj, Anand; Carrau, Ricardo; Panizza, Benedict; Solares, C Arturo

    2014-04-01

    Recent advances in endonasal endoscopy have facilitated the surgical access to the lateral skull base including areas such as Meckel's cave. This approach has been well documented, however, few studies have outlined transantral specific access to Meckel's. A transantral approach provides a direct pathway to this region obviating the need for extensive endonasal and transsphenoidal resection. Our aim in this study is to compare the anatomical perspectives obtained in endonasal and transantral approaches. We prepared 14 cadaveric specimens with intravascular injections of colored latex. Eight cadavers underwent endoscopic endonasal transpterygoid approaches to Meckel's cave. Six additional specimens underwent an endoscopic transantral approach to the same region. Photographic evidence was obtained for review. 30 CT scans were analyzed to measure comparative distances to Meckel's cave for both approaches. The endoscopic approaches provided a direct access to the anterior and inferior portions of Meckel's cave. However, the transantral approach required shorter instrumentation, and did not require clearing of the endonasal corridor. This approach gave an anterior view of Meckel's cave making posterior dissection more difficult. A transantral approach to Meckel's cave provides access similar to the endonasal approach with minimal invasiveness. Some of the morbidity associated with extensive endonasal resection could possibly be avoided. Better understanding of the complex skull base anatomy, from different perspectives, helps to improve current endoscopic skull base surgery and to develop new alternatives, consequently, leading to improvements in safety and efficacy.

  18. Observations on the Cave-Associated Beetles (Coleoptera of Nova Scotia, Canada

    Directory of Open Access Journals (Sweden)

    Moseley M.

    2009-07-01

    Full Text Available The cave-associated invertebrates of Nova Scotia constitute a fauna at a very early stage of post-glacial recolonization. TheColeoptera are characterized by low species diversity. A staphylinid Quedius spelaeus spelaeus, a predator, is the only regularlyencountered beetle. Ten other terrestrial species registered from cave environments in the province are collected infrequently. Theyinclude three other rove-beetles: Brathinus nitidus, Gennadota canadensis and Atheta annexa. The latter two together with Catopsgratiosus (Leiodidae constitute a small group of cave-associated beetles found in decompositional situations. Quedius s. spelaeusand a small suite of other guanophiles live in accumulations of porcupine dung: Agolinus leopardus (Scarabaeidae, Corticariaserrata (Latrididae, and Acrotrichis castanea (Ptilidae. Two adventive weevils Otiorhynchus ligneus and Barypeithes pellucidus(Curculionidae collected in shallow cave passages are seasonal transients; Dermestes lardarius (Dermestidae, recorded fromone cave, was probably an accidental (stray. Five of the terrestrial beetles are adventive Palaearctic species. Aquatic beetles arecollected infrequently. Four taxa have been recorded: Agabus larsoni (Dytiscidae may be habitual in regional caves; another Agabussp. (probably semivittatus, Dytiscus sp. (Dytiscidae, and Crenitis digesta (Hydrophilidae are accidentals. The distribution andecology of recorded species are discussed, and attention is drawn to the association of beetles found in a Nova Scotia “ice cave”.

  19. Concentration and stable carbon isotopic composition of CO2 in cave air of Postojnska jama, Slovenia

    Directory of Open Access Journals (Sweden)

    Magda Mandic

    2013-09-01

    Full Text Available Partial pressure of CO2 (pCO2 and its isotopic composition (δ13CairCO2 were measured in Postojnska jama, Slovenia, at 10 locations inside the cave and outside the cave during a one-year period. At all interior locations the pCO2 was higher and δ13CairCO2 lower than in the outside atmosphere. Strong seasonal fluctuations in both parameters were observed at locations deeper in the cave, which are isolated from the cave air circulation. By using a binary mixing model of two sources of CO2, one of them being the atmospheric CO2, we show that the excess of CO2 in the cave air has a δ13C value of -23.3 ± 0.7 ‰, in reasonable agreement with the previously measured soil-CO2 δ13C values. The stable isotope data suggest that soil CO2 is brought to the cave by drip water.

  20. Studies of condensation/evaporation processes in the Glowworm Cave, New Zealand

    Directory of Open Access Journals (Sweden)

    de Freitas Chris R.

    2006-07-01

    Full Text Available The condensation/evaporation process is important in caves, especially in tourist caves where there is carbon dioxide enriched air caused by visitors. The cycle of condensation and evaporation of condensate is believed to enhance condensation corrosion. The problem is condensation is difficult to measure. This study addresses the problem and reports on a method for measuring and modelling condensation rates in a limestone cave. Electronic sensors for measuring condensation and evaporation of the condensate as part of a single continuous process of water vapour flux are tested and used to collect 12 months of data. The study site is the Glowworm tourist cave in New Zealand. The work describes an explanatory model of processes leading to condensation using data based on measurements of condensation and evaporation as part of a single continuous process of water vapour flux. The results show that the model works well. However, one of the most important messages from the research reported here is the introduction of the condensation sensor. The results show that condensation in caves can actually be measured and monitored, virtually in real time. In conjunction with the recent developments in data logging equipment, this opens exciting perspectives in cave climate studies, and, more generally, in hydrogeological studies in karst terrains.

  1. Experimental Research on Internal Behaviors of Caved Rocks under the Uniaxial Confined Compression

    Directory of Open Access Journals (Sweden)

    Yu-jiang Zhang

    2017-01-01

    Full Text Available As main composition of longwall gob, caved rocks’ behaviors and their impacts under compression crucially influence strata control, subsidence, associated resources extraction, and many other aspects. However, current researches are based on a whole sample, due to looseness of caved rocks and limitation of observation technology. In this paper, an experiment system was built to investigate internal behaviors of caved rocks’ sample, under the uniaxial confined compression, including movement and breakage behavior by the digital image processing technologies. The results show that the compression process of caved rocks could be divided into two stages by relative density. Boundary effect and changes of voids and contact pressure among caved rocks lead to different movement law in different position in sample’s interior. A stratification phenomenon of breakage was discovered, which presents breakage concentration in the middle of the sample. The nonlinear movement and shear dislocation induced by shifts among caved rocks are the reason of the breakage stratification phenomenon. This phenomenon would have an effect on the permeability and seepage research of similar medium.

  2. “Spray Technique: Tracing the Sketch Traditions of Limestone Cave in Lenggong, Perak”

    Directory of Open Access Journals (Sweden)

    Yahaya Fatan Hamamah

    2015-01-01

    Full Text Available Archaeological research provides the widest opportunity for researchers to analyse various aspects and disciplines appropriate to the subject and the object of choice. Subject and object selection is the work of exploration artefacts found in particular sites and archaeological heritage. Exploration and excavation on of a world heritage site such as Lenggong enables researchers to uncover various archaeological artefacts that are rich and meaningful. To find evidence of the strength and benefits of an artefact, further studies on each artefact should be carried out continuously. This essay will track the wisdom of the ancient artists use to produce paintings in a limestone cave in Lenggong, Perak, using spray techniques. Some artefacts that are identified as cave paintings show a very interesting sketch technique that are unique and special. This essay will also examine some of the cave paintings in other caves in Perak and also other caves in several countries as comparison. Studies involving cave paintings in Malaysia are new compared to Western countries. Thus, the study of one of the technique which is spray technique can open the eyes of the audience to acknowledge and recognise the ancient heritage. It also hoped that this study is able to increase the body of knowledge that goes beyond the boundaries of the arts district and the country.

  3. The Astrobiology of the Subsurface: Caves and Rock Fracture Habitats on Earth, Mars and Beyond

    Science.gov (United States)

    Boston, Penelope J.

    2017-01-01

    The Astrobiology of the Subsurface: Exploring Cave Habitats on Earth, Mars and Beyond. We are using the spectacular underground landscapes of Earth caves as models for the subsurfaces of other planets. Caves have been detected on the Moon and Mars and are strongly suspected for other bodies in the Solar System including some of the ice covered Ocean Worlds that orbit gas giant planets. The caves we explore and study include many extreme conditions of relevance to planetary astrobiology exploration including high and low temperatures, gas atmospheres poisonous to humans but where exotic microbes can fluorish, highly acidic or salty fluids, heavy metals, and high background radiation levels. Some cave microorganisms eat their way through bedrock, some live in battery acid conditions, some produce unusual biominerals and rare cave formations, and many produce compounds of potential pharmaceutical and industrial significance. We study these unique lifeforms and the physical and chemical biosignatures that they leave behind. Such traces can be used to provide a Field Guide to Unknown Organisms for developing life detection space missions.

  4. Delayed child-bearing.

    Science.gov (United States)

    Johnson, Jo-Ann; Tough, Suzanne

    2012-01-01

    To provide an overview of delayed child-bearing and to describe the implications for women and health care providers. Delayed child-bearing, which has increased greatly in recent decades, is associated with an increased risk of infertility, pregnancy complications, and adverse pregnancy outcome. This guideline provides information that will optimize the counselling and care of Canadian women with respect to their reproductive choices. Maternal age is the most important determinant of fertility, and obstetric and perinatal risks increase with maternal age. Many women are unaware of the success rates or limitations of assisted reproductive technology and of the increased medical risks of delayed child-bearing, including multiple births, preterm delivery, stillbirth, and Caesarean section. This guideline provides a framework to address these issues. Studies published between 2000 and August 2010 were retrieved through searches of PubMed and the Cochrane Library using appropriate key words (delayed child-bearing, deferred pregnancy, maternal age, assisted reproductive technology, infertility, and multiple births) and MeSH terms (maternal age, reproductive behaviour, fertility). The Internet was also searched using similar key words, and national and international medical specialty societies were searched for clinical practice guidelines and position statements. Data were extracted based on the aims, sample, authors, year, and results. The quality of evidence was rated using the criteria described in the Report of the Canadian Task Force on Preventive Health Care (Table 1). The Society of Obstetricians and Gynaecologists of Canada. RECOMMENDATIONS 1. Women who delay child-bearing are at increased risk of infertility. Prospective parents, especially women, should know that their fecundity and fertility begin to decline significantly after 32 years of age. Prospective parents should know that assisted reproductive technologies cannot guarantee a live birth or completely

  5. Government Risk-Bearing

    CERN Document Server

    1993-01-01

    The u.s. government bulks large in the nation's financial markets. The huge volume of government-issued and -sponsored debt affects the pricing and volume ofprivate debt and, consequently, resource allocation between competing alternatives. What is often not fully appreciated is the substantial influence the federal government wields overresource allocation through its provisionofcreditandrisk-bearing services to the private economy. Because peopleand firms generally seekto avoid risk, atsomeprice they are willing to pay another party to assume the risk they would otherwise face. Insurance companies are a class of private-sector firms one commonly thinks of as providing these services. As the federal government has expanded its presence in the U.S. economy during this century, it has increasingly developed programs aimed at bearing risks that the private sector either would not take on at any price, or would take on but atapricethoughtto besogreatthatmostpotentialbeneficiarieswouldnotpurchase the coverage. To...

  6. Passive magnetic bearing system

    Science.gov (United States)

    Post, Richard F.

    2014-09-02

    An axial stabilizer for the rotor of a magnetic bearing provides external control of stiffness through switching in external inductances. External control also allows the stabilizer to become a part of a passive/active magnetic bearing system that requires no external source of power and no position sensor. Stabilizers for displacements transverse to the axis of rotation are provided that require only a single cylindrical Halbach array in its operation, and thus are especially suited for use in high rotation speed applications, such as flywheel energy storage systems. The elimination of the need of an inner cylindrical array solves the difficult mechanical problem of supplying support against centrifugal forces for the magnets of that array. Compensation is provided for the temperature variation of the strength of the magnetic fields of the permanent magnets in the levitating magnet arrays.

  7. Stacked magnet superconducting bearing

    International Nuclear Information System (INIS)

    Rigney, T.K. II; Saville, M.P.

    1993-01-01

    A superconducting bearing is described, comprising: a plurality of permanent magnets magnetized end-to-end and stacked side-by-side in alternating polarity, such that flux lines flow between ends of adjacent magnets; isolating means, disposed between said adjacent magnets, for reducing flux leakage between opposing sides of said adjacent magnets; and a member made of superconducting material having at least one surface in communication with said flux lines

  8. Radium bearing waste disposal

    International Nuclear Information System (INIS)

    Tope, W.G.; Nixon, D.A.; Smith, M.L.; Stone, T.J.; Vogel, R.A.; Schofield, W.D.

    1995-01-01

    Fernald radium bearing ore residue waste, stored within Silos 1 and 2 (K-65) and Silo 3, will be vitrified for disposal at the Nevada Test Site (NTS). A comprehensive, parametric evaluation of waste form, packaging, and transportation alternatives was completed to identify the most cost-effective approach. The impacts of waste loading, waste form, regulatory requirements, NTS waste acceptance criteria, as-low-as-reasonably-achievable principles, and material handling costs were factored into the recommended approach

  9. European Institutions?

    NARCIS (Netherlands)

    Meacham, Darian

    2016-01-01

    The aim of this article is to sketch a phenomenological theory of political institutions and to apply it to some objections and questions raised by Pierre Manent about the project of the European Union and more specifically the question of “European Construction”, i.e. what is the aim of the

  10. European Whiteness?

    DEFF Research Database (Denmark)

    Blaagaard, Bolette

    2008-01-01

    Born out of the United States’ (U.S.) history of slavery and segregation and intertwined with gender studies and feminism, the field of critical whiteness studies does not fit easily into a European setting and the particular historical context that entails. In order for a field of European...

  11. Magnetic translator bearings

    Science.gov (United States)

    Hockney, Richard L. (Inventor); Downer, James R. (Inventor); Eisenhaure, David B. (Inventor); Hawkey, Timothy J. (Inventor); Johnson, Bruce G. (Inventor)

    1990-01-01

    A magnetic bearing system for enabling translational motion includes a carriage and a shaft for movably supporting the carriage; a first magnetic bearing fixed to one of the carriage and shaft and slidably received in a first channel of the other of the carriage and shaft. The first channel is generally U shaped with two side walls and a back wall. The magnetic bearing includes a pair of spaced magnetic pole pieces, each pole piece having a pair of electromagnetic coils mounted on poles on opposite ends of the pole piece proximate the side walls, and a third electromagnetic coil mounted on a pole of the pole piece proximate the backwall; a motion sensor for sensing translational motion along two axes and rotationally about three axes of the carriage and shaft relative to each other; and a correction circuit responsive to the sensor for generating a correction signal to drive the coils to compensate for any misalignment sensed between the carriage and the shaft.

  12. Cave invertebrates in Espírito Santo state, Brazil: a primary analysis of endemism, threats and conservation priorities

    Directory of Open Access Journals (Sweden)

    Marconi Souza Silva

    2015-08-01

    Full Text Available The cave-dwelling invertebrates were studied according to their composition, biodiversity, distribution and threats in the Atlantic Forest Central Biodiversity Corridor, a priority area for conservation actions in Brazil. Twelve obligate cave species were found, plus 495 troglophile species. Araneae (103 spp., Coleoptera (61 spp., Diptera (56 spp. and Lepidoptera (38 spp. were the richest taxa. The richness was higher in the carbonate caves (63 spp., sd = 16.7 and the highest diversity in granitic caves (H´= 2.68, sd = 0.5. The spatial turnover was 63.45 and similarity less than 30%. The total richness was correlated with the linear extension of the caves (Rs = 0.757, p ≤ 0.05. Surrounding area deforestation and religious and tourist use were the main threats. Emergency attention is recommended regarding protective actions, management and conservation of caves of extremely high biological importance.

  13. The Sinicization of Dunhuang Mogao Cave Buddhist Art

    Directory of Open Access Journals (Sweden)

    Ōhashi Katsuaki

    2014-02-01

    Full Text Available The introduction of Indian Buddhism in China occurred around the Christian era. However, Indian Buddhism was not directly accepted by the Han Chinese as they could not rival the philosophical religions which were already in existence. The existing philosophical religions were Confucianism and Taoism; therefore Indian Buddhism was not a necessity for the Han Chinese. Large volumes of Indian Buddhist scriptures, written in ancient Hindustani, began to be translated into Chinese, known as the ‘Chinese Translation Project.’ Accordingly, Chinese translations of Buddhist scriptures appeared. As for the Chinese translations, it was clear that ancient Chinese philosophies were instilled into these translations in order to make them more easily acceptable by the Han Chinese. It took a long period of time, around 200 years, for Indian Buddhism to assimilate into Chinese culture. Once Indian Buddhism was embraced by East Asia’s largest developed country, the foundations of Chinese civilization such as Chinese characters, paintings, sculptures, crafts, architecture, construction, and casting methods, then were transformed by Chinese Buddhism and Chinese Buddhist art. In the instance when one developed civilized country adopts features of another developed civilization, it takes a long period of time for harmonization to occur. However, within a short period of time, Chinese Buddhism became a significant culture within the East Asia region, and was accepted in the surrounding regions of China, such as the Korean Peninsula and islands of Japan. However, soon after the collapse of the Han Dynasty in 220A.D, the country was divided into three parts and the troubled time of 5 Hu 16 Guo began. Most aristocrats, bureaucrats and people in Chang’an became refugees, escaping towards the southern area of the Gansu River. Among them, painters and sculptors from Chang’an created splendid wall paintings and produced luxurious clay statues in the Mogao Caves. At

  14. Bearing for liquid metal pump

    International Nuclear Information System (INIS)

    Dickinson, R.J.; Pennell, W.E.; Wasko, J.

    1984-01-01

    A liquid metal pump bearing support comprises a series of tangentially oriented spokes that connect the bearing cylinder to the pump internals structure. The spokes may be arranged in a plurality of planes extending from the bearing cylinder to the pump internals with the spokes in one plane being arranged alternately with those in the next plane. The bearing support structure provides the pump with sufficient lateral support for the bearing structure together with the capability of accommodating differential thermal expansion without adversely affecting pump performance

  15. Assessment of Brown Bear\\'s (Ursus arctos syriacus Winter Habitat Using Geographically Weighted Regression and Generalized Linear Model in South of Iran

    Directory of Open Access Journals (Sweden)

    A. A. Zarei

    2016-03-01

    Full Text Available Winter dens are one of the important components of brown bear's (Ursus arctos syriacus habitat, affecting their reproduction and survival. Therefore identification of factors affecting the habitat selection and suitable denning areas in the conservation of our largest carnivore is necessary. We used Geographically Weighted Logistic Regression (GWLR and Generalized Linear Model (GLM for modeling suitability of denning habitat in Kouhkhom region in Fars province. In the present research, 20 dens (presence locations and 20 caves where signs of bear were not found (absence locations were used as dependent variables and six environmental factors were used for each location as independent variables. The results of GLM showed that variables of distance to settlements, altitude, and distance to water were the most important parameters affecting suitability of the brown bear's denning habitat. The results of GWLR showed the significant local variations in the relationship between occurrence of brown bear dens and the variable of distance to settlements. Based on the results of both models, suitable habitats for denning of the species are impassable areas in the mountains and inaccessible for humans.

  16. Competition of wormholes during the evolution of cave passages

    Science.gov (United States)

    Gabrovsek, Franci; Dreybrodt, Wolfgang

    2017-04-01

    Reactive fronts in two-dimensional plane parallel fractures, with constant head difference between input and output and with diffusion controlled first order reaction rates R = keff ṡ (Ceq - C), where keff = k ṡ (1 + ka/6D)-1, are instable to infinitesimal perturbations in fracture aperture width (1), causing spontaneous fingering of the reactive front resulting in the formation of wormholes. C is the actual concentration and Ceq the equilibrium concentration, a, is the actual aperture width of the fracture , and D the constant of molecular diffusion. Fingering happens also in plane-parallel rough fractures where it is triggered by the existence of statistically more favorable pathways. The same behavior is observed in rectangular two-dimensional networks of "one-dimensional" smooth fractures used in modeling the evolution of caves in soluble rock (2). Here the formation of caves can be regarded as the evolution of wormholes along the two-dimensional network. Once fingering has been triggered, either by instability or by roughness, many small fingers compete with each other and only a few survive. Here we investigate the competition between two seeded fingers in initially homogeneous fracture networks with identical aperture width of all fractures and also in inhomogeneous ones where the aperture widths are distributed log normally. In both cases our modeling reveals the rules of competition: By instability one of the fingers grows faster than its competitor therefore penetrating somewhat deeper. As a consequence the hydraulic head at its tip is higher than that close to the tip of the shorter finger. Therefore the fractures connecting the tip regions of both fingers carry flow from the deep finger to the tip region of its competitor. This cross-flow is replaced by increasing inflow of aggressive solution into the input of the winner, enhancing further dissolution and growth. On the other hand the cross-flow increases the head at the tip of the losing finger

  17. Radon exposure, chromosomal aberrations, and genetic polymorphisms in selected Slovak cave workers

    International Nuclear Information System (INIS)

    Musak, L.; Pec, M.; Vicanova, M.; Vodicka, P.; Hanova, M.; Buchancova, J.; Moravcikova, K.; Klimentova, G.; Vodickova, L.

    2005-01-01

    The aim of work was genotoxic risk assessment of the Slovak show cave workers employed by the Slovak Caves Administration in Liptovsky Mikulas. They are guides or administrators of the four Slovak show caves: Vazecka, Demanovska, Bystrianska, and Harmanecka. We examined 51 workers exposed to radon, with average age 35.64 years ± 6.63 (SD) and average exposition time 9.78 years ± 6.27 (SD). They are 43 men (i.e. 84.31 %) and 9 women (i.e. 15.69 %). The control group consisted of 32 healthy workers from Faculty Hospital in Martin. The workers were not exposed to any genotoxic agents. The average age is 31.84 years ± 5.84(SD). From every subject we evaluated 100 mitosis, i.e. 5100 mitosis from exposed workers and 3200 mitosis from control subjects. In exposed group we found in 111 cells chromosomal aberrations, this present 2.18 % Ab.c. ± 0.19 (SEM), and in control 1 st group 1.53 % ± 0.16 (SEM). There are 106 breaks (95.50%), and 5 exchanges (4.50%) on chromosomes. The highest number of Ab.c. we detected in workers of Vazecka (2.63 % Ab.c) and Bystrianska (2.00 % Ab.c.) caves. There is a significant increase (P < 0.05) in the mean number of Ab.c. in workers of cave Vazecka as compared to control. In 15 cases (i.e. 28.30 %) we found increase or high exposure to genotoxic agents, we found any difference between sex, and any dependence of the number of Ab.c. on age and time of exposure. The Vazecka cave workers showed three times higher mean effective doses all the year round (milliSievert) than workers additional caves. The measured values of radiation in the caves and mines exceeded the permissible limits and Regional Hygienist of the Central Slovakia declared in 1981 the risk zones and, at the same time, the monitoring of working atmosphere was initiated. Our evaluations referred to certain exposition of this carcinogen in cave workers too. The essence of prevention is based in the lowering of ionizing radiation and improvement of the sanitary

  18. Bearing construction for refrigeration compresssor

    Science.gov (United States)

    Middleton, Marc G.; Nelson, Richard T.

    1988-01-01

    A hermetic refrigeration compressor has a cylinder block and a crankshaft rotatable about a vertical axis to reciprocate a piston in a cylinder on the cylinder block. A separate bearing housing is secured to the central portion of the cylinder block and extends vertically along the crankshaft, where it carries a pair of roller bearings to journal the crankshaft. The crankshaft has a radially extending flange which is journaled by a thrust-type roller bearing above the bearing housing to absorb the vertical forces on the crankshaft so that all three of the roller bearings are between the crankshaft and the bearing housing to maintain and control the close tolerances required by such bearings.

  19. Mamalia, Chiroptera, Vespertilionidae: Filling hibernacula distribution gaps for cave roosting bats from Iowa (U.S.A..

    Directory of Open Access Journals (Sweden)

    Dixon, J. W.

    2010-01-01

    Full Text Available Adequate roost sites for hibernacula are an important factor in the distribution and abundance of temperate batspecies and knowledge of specific hibernacula is necessary to make sound management decisions. Caves are recognized asone of the most important roosting sites for bats, yet surveys in caves are uncommon in North America. This paper presentsdata on the distribution and abundance of bats hibernating in Iowa (U.S.A. caves and includes new hibernacula records.These are the first published records of bats in Iowa caves in almost 25 years.

  20. Hydrochemical controls on aragonite versus calcite precipitation in cave dripwaters

    Science.gov (United States)

    Rossi, Carlos; Lozano, Rafael P.

    2016-11-01

    Despite the paleoclimatic relevance of primary calcite to aragonite transitions in stalagmites, the relative role of fluid Mg/Ca ratio, supersaturation and CO32- concentration in controlling such transitions is still incompletely understood. Accordingly, we have monitored the hydrochemistry of 50 drips and 8 pools that are currently precipitating calcite and/or aragonite in El Soplao and Torca Ancha Caves (N. Spain), investigating the mineralogy and geochemistry of the CaCO3 precipitates on the corresponding natural speleothem surfaces. The data reveal that, apart from possible substrate effects, dripwater Mg/Ca is the only obvious control on CaCO3 polymorphism in the studied stalagmites and pools, where calcite- and aragonite-precipitating dripwaters are separated by an initial (i.e. at stalactite tips) Mg/Ca threshold at ≈1.1 mol/mol. Within the analyzed ranges of pH (8.2-8.6), CO32- concentration (1-6 mg/L), supersaturation (SIaragonite: 0.08-1.08; SIcalcite: 0.23-1.24), drip rate (0.2-81 drops/min) and dissolved Zn (6-90 μg/L), we observe no unequivocal influence of these parameters on CaCO3 mineralogy. Despite the almost complete overlapping supersaturations of calcite- and aragonite-precipitating waters, the latter are on average less supersaturated because the waters having Mg/Ca above ∼1.1 have mostly achieved such high ratios by previously precipitating calcite. Both calcite and aragonite precipitated at or near oxygen isotopic equilibrium, and Mg incorporation into calcite was consistent with literature-based predictions, indicating that in the studied cases CaCO3 precipitation was not significantly influenced by strong kinetic effects. In the studied cases, the calcites that precipitate at ∼11 °C from dripwaters with initial Mg/Ca approaching ∼1.1 incorporate ∼5 mol% MgCO3, close to the published value above which calcite solubility exceeds aragonite solubility, suggesting that aragonite precipitation in high-relative-humidity caves is

  1. 77 FR 70423 - Black Bear Hydro Partners, LLC and Black Bear Development Holdings, LLC and Black Bear SO, LLC...

    Science.gov (United States)

    2012-11-26

    ... Bear Hydro Partners, LLC and Black Bear Development Holdings, LLC and Black Bear SO, LLC; Notice of..., 2012, Black Bear Hydro Partners, LLC, sole licensee (transferor) and Black Bear Development Holdings, LLC and Black Bear SO, LLC (transferees) filed an application for the partial the transfer of licenses...

  2. Introgressive hybridization: brown bears as vectors for polar bear alleles.

    Science.gov (United States)

    Hailer, Frank

    2015-03-01

    The dynamics and consequences of introgression can inform about numerous evolutionary processes. Biologists have therefore long been interested in hybridization. One challenge, however, lies in the identification of nonadmixed genotypes that can serve as a baseline for accurate quantification of admixture. In this issue of Molecular Ecology, Cahill et al. (2015) analyse a genomic data set of 28 polar bears, eight brown bears and one American black bear. Polar bear alleles are found to be introgressed into brown bears not only near a previously identified admixture zone on the Alaskan Admiralty, Baranof and Chichagof (ABC) Islands, but also far into the North American mainland. Elegantly contrasting admixture levels at autosomal and X chromosomal markers, Cahill and colleagues infer that male-biased dispersal has spread these introgressed alleles away from the Late Pleistocene contact zone. Compared to a previous study on the ABC Island population in which an Alaskan brown bear served as a putatively admixture-free reference, Cahill et al. (2015) utilize a newly sequenced Swedish brown bear as admixture baseline. This approach reveals that brown bears have been impacted by introgression from polar bears to a larger extent (up to 8.8% of their genome), than previously known, including the bear that had previously served as admixture baseline. No evidence for introgression of brown bear into polar bear is found, which the authors argue could be a consequence of selection. Besides adding new exciting pieces to the puzzle of polar/brown bear evolutionary history, the study by Cahill and colleagues highlights that wildlife genomics is moving from analysing single genomes towards a landscape genomics approach. © 2015 John Wiley & Sons Ltd.

  3. Selective Europeanization

    DEFF Research Database (Denmark)

    Hoch Jovanovic, Tamara; Lynggaard, Kennet

    2014-01-01

    and rules. The article examines the reasons for both resistance and selectiveness to Europeanization of the Danish minority policy through a “path dependency” perspective accentuating decision makers’ reluctance to deviate from existing institutional commitments, even in subsequently significantly altered...... political contexts at the European level. We further show how the “translation” of international norms to a domestic context has worked to reinforce the original institutional setup, dating back to the mid-1950s. The translation of European-level minority policy developed in the 1990s and 2000s works most...

  4. 222 Rn exposure assessment in the caves of Parque Estadual Turistico do Alto Ribeira (PETAR)

    International Nuclear Information System (INIS)

    Alberigi, Simone

    2006-01-01

    In the present work, radon concentrations in six caves of PETAR - Parque Estadual Turistico do Alto Ribeira (High Ribeira River Touristic State Park) were carried out with Makrofol E solid state nuclear track detectors (SSNTD) and used to assess the annual effective dose received by regional tour guides. The park has four visitation centers: Santana, Ouro Grosso, Caboclos e Casa de Pedra and receives nearly 40,000 people annually. The caves evaluated were Couto, Agua Suja, Laje Branca, Morro Preto and Santana, from Santana center and Alambari de Baixo from Ouro Grosso center, for being the most frequently visited caves. The exposure period of the SSNTD was, at least, three months, over a period of 26 months, from October 2003 to November 2005.The 222 Rn concentrations lay in a range from 153 Bq.m -3 to 6607 Bq.m -3 and we observed that, in general, for chilly weather, the radon levels decrease. The annual effective dose, considering the most realistic scenario, with geometric mean concentrations, an equilibrium factor of 0.5 and annual exposure time for each cave, varied from 0.2 mSv.a -1 for the Couto cave, strongly ventilated, to 4.0 mSv.a -1 for the Santana cave, the most frequently visited and no external communication. For the worst scenario, with arithmetic mean concentrations, equilibrium factor 1 and annual exposure time for all caves, the annual effective dose was 16.1 mSv.a -1 . All assessed effective doses received by the tour guides are bellow 20 mSv.a -1 suggested as an annual effective dose limit for occupational exposure by the International Commission of Radiological Protection (ICRP 60, 1990). (author)

  5. Report of a three-year monitoring programme at Heshang Cave, Central China

    Directory of Open Access Journals (Sweden)

    Chaoyong Hu

    2008-10-01

    Full Text Available Heshang Cave is situated in central China (30º27’N, 110º25’E; 294 m in the middle reaches of the Yangtze Valley, a region stronglyimpacted by the East Asian Monsoon. It contains large annually-laminated Holocene and late Pleistocene stalagmites which capture pastmonsoon behaviour with seasonal resolution, and could enhance understanding of the amplitude and frequency of monsoon behaviour indifferent climate states. In this paper, we present results of a 3-year monitoring programme at Heshang. T loggers outside the cave agree closely with T data from nearby meteorological stations. T at the site of growth of the largest recovered stalagmite averages 18ºC (identical to mean annual T outside the cave with a seasonal amplitude of 5ºC (about one fifth of the external cycle. Rainfall measurements from a station 3 km from the cave indicate strong summer monsoon rain in 2004 and 2005, but rather weaker summer rain (by ≈30% in 2006.Drip rate at the monitoring site has a base flow of 14 drips/minute and shows a sharp increase to ≈40 drips/minute early in the summerrains of 2004 and 2005, followed by a gradual return to base-flow as the monsoon weakens. This abrupt change presumably representsthreshold behaviour in the hydrological system. This threshold is not passed in 2006 and there is no abrupt increase in drip rate, indicating the sensitivity of this site (and presumably of speleothem chemistry in this cave to monsoon rainfall. Results are also reported from a 10-month deployment of a Stalagmate drip counter, and for CO2 levels in Heshang Cave. Overall, this monitoring work represents an essential dataset for interpretation of the chemistry of drip waters, of carbonates grown on glass slides and, ultimately, of long speleothem records of past climate from Heshang Cave.

  6. New updated results of paleomagnetic dating of cave deposits exposed in Za Hájovnou Cave, Javoříčko Karst

    Czech Academy of Sciences Publication Activity Database

    Kadlec, Jaroslav; Čížková, Kristýna; Šlechta, Stanislav

    2014-01-01

    Roč. 70, 1-2 (2014), s. 27-34 ISSN 0036-5343 Institutional support: RVO:67985530 ; RVO:67985831 Keywords : Javoříčko Karst * Za Hájovnou Cave * Early and Middle Pleistocene * paleomagnetic dating Subject RIV: DB - Geology ; Mineralogy

  7. Orthothermographies and 3D modeling as potential tools in ice caves studies: the Peña Castil Ice Cave (Picos de Europa, Northern Spain

    Directory of Open Access Journals (Sweden)

    Fernando Berenguer-Sempere

    2014-01-01

    Full Text Available Currently there are many studies focused on the investigation of climatic and glaciological condition of ice caves. Here we present another way to address these studies, applying some methods already used in fields other than geomorphology. The versatility and accuracy provided by the use of modern topography and thermography techniques, using Terrestrial Laser Scanner and current thermographic cameras- and the creation of 3D thermographic models and orthothermographies derived from them - is shown to be a useful tool as it is difficult to obtain data from fieldwork and traditional methods used in caves. This paper presents the potential uses of combined TLS and thermographic techniques for monitoring some important climatological parameters in the sensitive periglacial environment of the Iberian Atlantic high mountains: Peña Castil Ice Cave (Picos de Europa, Northern Spain. A systematic application of such combined technologies to these kind of caves, is expected to contribute to a quantitative and concise characterization of the evolution of the ice as shown by the results of this study.

  8. Diversity of cultivable bacteria involved in the formation of macroscopic microbial colonies (Cave silver on the walls of a cave in Slovenia

    Directory of Open Access Journals (Sweden)

    Blagajana Herzog Velikonja

    2014-01-01

    Full Text Available Karstic caves often support white, yellow, grey or pink microbial colonies that are termed ‘cave silver’ by speleologists. Using various sample pre-treatments and culture media, a wide variety of bacteria associated with these colonies were recovered from a cave in Slovenia, Pajsarjeva jama. Decreasing the inoculum size resulted in significant increases in viable counts, while pre-treatments had the opposite effect with the exception of microwave irradiation. While all growth media yielded viable counts, the maximal counts were observed on a low-nutrient TWA medium. Based on the 16S rRNA gene sequence of OTU representatives, the majority of the 80 isolates examined belonged to Streptomyces (25%, Micrococcus (16% and Rhodococcus (10% Other abundant groups were Pseudomonas (9%, Agrobacterium (8%, Lysobacter (6% and Paenibacillus (5%, while members of genera Microbacterium, Agrococcus, Arthrobacter, Bacillus, Kocuria, Oerskovia, Sphingomonas, Aerococcus, and Bosea represented a minor portion of cultivable diversity encountered. Members of Streptomyces and Agrobacterium were common to all samples. Although these microorganisms readily form colonies under laboratory conditions, they were unrelated to abundant environmental phylotypes recovered from same samples in a previous study. However, the comparative 16S rRNA analysis showed that microorganisms highly related to the ones obtained in this study were cultivated from other subterranean environments indicating that they might represent true microbial cave dwellers.

  9. Self lubricating fluid bearings

    International Nuclear Information System (INIS)

    Kapich, D.D.

    1980-01-01

    The invention concerns self lubricating fluid bearings, which are used in a shaft sealed system extending two regions. These regions contain fluids, which have to be isolated. A first seal is fluid tight for the first region between the carter shaft and the shaft. The second seal is fluid tight between the carter and the shaft, it communicates with the second region. The first fluid region is the environment surrounding the shaft carter. The second fluid region is a part of a nuclear reactor which contains the cooling fluid. The shaft is conceived to drive a reactor circulating and cooling fluid [fr

  10. Performance and safety analysis of WP-cave concept

    International Nuclear Information System (INIS)

    Skagius, K.; Svemar, C.

    1989-08-01

    The report presents a performance safety, and cost analysis of the WP-cave, WPC, concept. In the performance analysis, questions specific to the WPC have been addressed which have been identified to require more detailed studies. Based on the outcome of this analysis, a safety analysis has been made which comprises of the modeling and calculation of radionuclide transport from the repository to the biosphere and the resulting dose exposure to man. The result of the safety analysis indicates that the present design of a WPC repository may give unacceptably high doses. By improving the properties of the bentonite/sand barrier such that the hydraulic conductivity is reduced, or by changing the short-lived steel canisters to more long-lived canisters, e.g. copper canisters, it is judged possible to achieve a sufficiently low level of dose exposure rates to man. The cost for a WPC repository of the studied design is significantly higher than for a KBS-3 repository considering the Swedish conditions and the Swedish amount of spent fuel. The major costs are connected to the excavation and backfilling of the bentonite/sand barrier. The potential for cost savings is high but it is not judged possible to account for savings in such a way that the WPC concept shows lower cost than the KBS-3 concept. (34 figs., 33 tabs., 29 refs.)

  11. Mishmarot Calendars from Qumran Cave 4: Congruence and Divergence

    Science.gov (United States)

    Snyder, George, Jr.

    1997-09-01

    This study examines the calendar observed by the sect whose writings have been found in the caves of the Judean desert. Chapter I introduces the Qumran calendar as an outgrowth of the 364-day pseudo-solar year described in the astronomical chapters of 1 Enoch and defended in the Book of Jubilees. The Temple Scroll completes a calendric foundation by making canonical several summer harvest festivals not found in the Hebrew Scriptures. Chapters II through VII detail the eight mishmarot manuscripts, providing text, translation, and analysis toward understanding the fully developed calendric structure. These investigations manifest arguments that establish the beginning of the sect's lunar month at the full moon, present coordination methodologies that balance the 364-day solar year with the 354-day lunar one, and reveal two different arrangements of the festival cycle. The Conclusion gathers under the heads of Enoch and Jubilees evidence to propose two sectarian calendar traditions and brings forward other texts which could be similarly categorized. Three appendices and a glossary support the discussion from non-mishmarot calendars and presenting an eclectic six-year calendar in full detail.

  12. European Security

    DEFF Research Database (Denmark)

    Møller, Bjørn

    Theoretical chapters on "Security", "Organisations" and "Regions," Historical Chapters on "Europe and Its Distinguishing Features" and on "The United Nations," "NATO," "The CSCE/OSCE and the Council of Europe" and "The European Union"......Theoretical chapters on "Security", "Organisations" and "Regions," Historical Chapters on "Europe and Its Distinguishing Features" and on "The United Nations," "NATO," "The CSCE/OSCE and the Council of Europe" and "The European Union"...

  13. High Resolution Time Series Cave Ventilation Processes and the Effects on Cave Air Chemistry and Drip Waters: Speleoclimatology and Proxy Calibration

    Science.gov (United States)

    Kowalczk, A. J.; Froelich, P. N.; Gaffka, C.; Tremaine, D.

    2008-12-01

    Continuous high resolution (sub-hourly), long-term (Nov 2007-present) monitoring of cave air chemistry (Temperature, Relative Humidity, Barometric Pressure, Radon-222, CO2, Air flow, Wind speed and direction) in a shallow subtropical cave (Hollow Ridge) in N Florida reveals two major ventilation mechanisms: 1) ventilation driven by winds across the cave entrances, and 2) ventilation driven by density differences between atmospheric and cave air. The degree and type of ventilation strongly influence the 222Rn and CO2 of cave air, which in turn affects the timing and extent of calcite deposition in speleothems. The degree of ventilation is estimated using a cave air CO2-δ13CO2 Keeling Plot, or a simple radon deficiency model. Results show cave air has an atmospheric component ranging from 10-90%. During fall and winter, average CO2 (700 ppmv) and 222Rn (50-100 dpm/L) are lower than in spring and summer (CO2 = 1200 ppmv; 222Rn = 1000 dpm/L) due to increased winter ventilation. Decreased ventilation during the summer allows CO2 and 222Rn levels to rise. Winter daily ventilation is primarily a function of density gradients between cave air and atmospheric air, while summer daily ventilation is primarily a function of late morning NW-NE winds above the cave. Stable isotope analyses of drip water (fracture drip and pore flow drip) and aquifer water from Hollow Ridge agree with previous isotope studies of drip water at Florida Caverns State Park, 2 km to the NE. During summer, isotopic composition of pore flow drip water (δ18O -3.8 to -4.0 per mil; δD -17.3 to -20.2 per mil VSMOW) and aquifer water (δ18O -4.0 per mil; δD -18.0 to -21.1 per mil) are similar to average annual weighted isotopic composition of precipitation (δ18O -3.6 per mil) while fracture drip waters (δ18O -3 to -3.4 per mil; δD -11.9 to -14.3 per mil) likely reflect the isotopic composition of individual precipitation events. Pore flow drip waters δ18O are weakly correlated with drip rates

  14. European Community.

    Science.gov (United States)

    1987-05-01

    The European Community was established in 1951 to reconcile France and Germany after World War II and to make possible the eventual federation of Europe. By 1986, there were 12 member countries: France, Italy, Belgium, the Federal Republic of Germany, Luxembourg, the Netherlands, Denmark, Ireland, the United Kingdom, Greece, Spain, and Portugal. Principal areas of concern are internal and external trade, agriculture, monetary coordination, fisheries, common industrial and commercial policies, assistance, science and research, and common social and regional policies. The European Community has a budget of US$34.035 billion/year, funded by customs duties and 1.4% of each member's value-added tax. The treaties establishing the European Community call for members to form a common market, a common customs tariff, and common agricultural, transport, economic, and nuclear policies. Major European Community institutions include the Commission, Council of Ministers, European Parliament, Court of Justice, and Economic and Social Committee. The Community is the world's largest trading unit, accounting for 15% of world trade. The 2 main goals of the Community's industrial policy are to create an open internal market and to promote technological innovation in order to improve international competitiveness. The European Community aims to contribute to the economic and social development of Third World countries as well.

  15. Spatial and temporal changes in invertebrate assemblage structure from the entrance to deep-cave zone of a temperate marble cave

    Directory of Open Access Journals (Sweden)

    Benjamin W. Tobin

    2013-09-01

    Full Text Available Seasonality in surface weather results in seasonal temperature and humidity changes in caves. Ecological and physiological differences among trogloxenes, troglophiles, and troglobionts result in species-dependent responses to this variability. To investigate these responses, we conducted five biological inventories in a marble cave in the Sierra Nevada Range, California, USA between May and December 2010. The cave was divided into six quadrats and temperature was continuously logged in each (humidity was logged at the entrance and in the deep cave. With increasing distance from the entrance, temperature changes were increasingly attenuated and lagged relative to surface temperature. Linear regressions were created to determine the relationship between measured environmental variables and diversity for cavernicoles (troglobionts and troglophiles and trogloxenes cave– wide and in the transition zone. Diversity for cavernicoles and trogloxenes peaked in the entrance and deep cave zones, respectively. Quadrat, date, 2-week antecedent temperature average, 2-week antecedent temperature range, and trogloxene abundance explained 76% of cavernicole diversity variability. Quadrat explained 55% of trogloxene diversity variability. In the transition zone, trogloxene abundance explained 26% of cavernicole variability and 2-week antecedent temperature and 2-week antecedent temperature range explained 40% of trogloxene variability. In the transition zone, trogloxene diversity was inversely related to 2-week antecedent temperature average and 2-week antecedent temperature range, suggesting that species were moving into the transition zone when temperature was most stable. In a CCA of cavernicoles distribution data and environmental variables, 35% of variation in species-specific distributions was attributable to quadrat, and non-significant percentages were explained by date and environmental variables. Differences in assemblage structure among quadrats were

  16. Nanoprecipitation in bearing steels

    International Nuclear Information System (INIS)

    Barrow, A.T.W.; Rivera-Diaz-del-Castillo, P.E.J.

    2011-01-01

    θ-phase is the main hardening species in bearing steels and appears in both martensitically and bainitically hardened microstructures. This work presents a survey of the microstrucural features accompanying nanoprecipitation in bearing steels. Nanoprecipitate structures formed in 1C-1.5Cr wt.% with additions of Cr, Mn, Mo, Si and Ni are studied. The work is combined with thermodynamic calculations and neural networks to predict the expected matrix composition, and whether this will transform martensitically or bainitically. Martensite tetragonality, composition and the amount of retained austenite are related to hardness and the type of nanoprecipitate structures in martensitic grades. The θ-phase volume fraction, the duration of the bainite to austenite transformation and the amount of retained austenite are related to hardness and a detailed quantitative description of the precipitate nanostructures. Such description includes compositional studies using energy-dispersive spectroscopy, which shows that nanoprecipitate formation takes place under paraequilibrium. Special attention is devoted to a novel two-step bainite tempering process which shows maximum hardness; we prove that this is the most effective process for incorporating solute into the precipitates, which are finer than those resulting from one-step banitic transformation processes.

  17. Superconducting bearings in flywheels

    Energy Technology Data Exchange (ETDEWEB)

    Coombs, T.A.; Campbell, A.M.; Ganney, I.; Lo, W. [Cambridge Univ. (United Kingdom). Interdisciplinary Research Centre in Superconductivity (IRC); Twardowski, T. [International Energy Systems, Chester High Road, Neston, South Wirral (United Kingdom); Dawson, B. [British Nuclear Fuels, Capenhurst, South Wirral (United Kingdom)

    1998-05-01

    Investigations are being carried out into the use of superconducting magnetic bearings to levitate energy storage flywheels. In a planned program of work, Cambridge University are aiming to produce a practical bearing system for Pirouette(TM). The Pirouette(TM) system is designed to provide 5 kWh of recoverable energy which is currently recoverable at a rate of 5 kW (future revisions will provide up to 50 kW). IES (a British Nuclear Fuels subsidiary) the owners of the Pirouette(TM) machine have supplied Cambridge with a flywheel. This flywheel weighs >40 kg and is being levitated using an Evershed-type arrangement in which the superconductor is being used to stabilize the interaction between two magnets. To date we have demonstrated stable levitation in static and low speed tests in a rig designed for low speeds of rotation in air. A second rig which is currently under construction at BNFL will run in vacuum at speeds of up to 50 (orig.) 5 refs.

  18. Cave Conservation Priority Index to Adopt a Rapid Protection Strategy: A Case Study in Brazilian Atlantic Rain Forest

    Science.gov (United States)

    Souza Silva, Marconi; Martins, Rogério Parentoni; Ferreira, Rodrigo Lopes

    2015-02-01

    Cave environments are characterized by possessing specialized fauna living in high environmental stability with limited food conditions. These fauna are highly vulnerable to impacts, because this condition can frequently be easily altered. Moreover, environmental determinants of the biodiversity patterns of caves remain poorly understood and protected. Therefore, the main goal of this work is to propose a cave conservation priority index (CCPi) for a rapid assessment for troglobiotic and troglophile protection. Furthermore, the troglobiotic diversity, distribution and threats have been mapped in the Brazilian Atlantic forest. To propose the CCPi, the human impacts and richness of troglobiotic and troglophile species of 100 caves were associated. Data related to troglomorphic/troglobiotic fauna from another 200 caves were used to map the troglobiotic diversity and distribution. The CCPi reveals extremely high conservation priority for 15 % of the caves, high for 36 % and average for 46 % of the caves. Fourteen caves with extremely high priorities should have urgent conservation and management actions. The geographical distribution of the 221 known troglobiotic/troglomorphic species allowed us to select 19 karst areas that need conservation actions. Seven areas were considered to have urgent priority for conservation actions. The two richest areas correspond to the "iron quadrangle" with iron ore caves (67 spp.) and the "Açungui limestone group" (56 spp.). Both areas have several caves and are important aquifers. The use of the CCPi can prevent future losses because it helps assessors to select caves with priorities for conservation which should receive emergency attention in relation to protection, management and conservation actions.

  19. Winter distribution and use of high elevation caves as foraging sites by the endangered Hawaiian hoary bat, Lasiurus cinereus semotus

    Science.gov (United States)

    Bonaccorso, Frank; Montoya-Aiona, Kristina; Pinzari, Corinna A.; Todd, Christopher M.

    2016-01-01

    We examine altitudinal movements involving unusual use of caves by Hawaiian hoary bats, Lasiurus cinereus semotus, during winter and spring in the Mauna Loa Forest Reserve (MLFR), Hawai‘i Island. Acoustic detection of hoary bat vocalizations, were recorded with regularity outside 13 lava tube cave entrances situated between 2,200 to 3,600 m asl from November 2012 to April 2013. Vocalizations were most numerous in November and December with the number of call events and echolocation pulses decreasing through the following months. Bat activity was positively correlated with air temperature and negatively correlated with wind speed. Visual searches found no evidence of hibernacula nor do Hawaiian hoary bats appear to shelter by day in these caves. Nevertheless, bats fly deep into caves as evidenced by numerous carcasses found in cave interiors. The occurrence of feeding buzzes around cave entrances and visual observations of bats flying in acrobatic fashion in cave interiors point to the use of these spaces as foraging sites. Peridroma moth species (Noctuidae), the only abundant nocturnal, flying insect sheltering in large numbers in rock rubble and on cave walls in the MLFR, apparently serve as the principal prey attracting hoary bats during winter to lava tube caves in the upper MLFR. Caves above 3,000 m on Mauna Loa harbor temperatures suitable for Pseudogymnoascus destructansfungi, the causative agent of White-nose Syndrome that is highly lethal to some species of North American cave-dwelling bats. We discuss the potential for White-nose Syndrome to establish and affect Hawaiian hoary bats.

  20. Basaltic caves at Craters of the Moon National Monument and Preserve as analogs for Mars

    Science.gov (United States)

    Hinman, N. W.; Richardson, C. D.; McHenry, L.; Scott, J. R.

    2010-12-01

    Basaltic caves and lava tubes offer stable physicochemical conditions for formation of secondary minerals. Such features, putatively observed on Mars, intercept groundwater to weather country rock, leading to formation of secondary minerals. Further, caves are stable environments to search for evidence of past life, as they could offer protection from the oxidizing martian atmosphere. Searching for signs of life in a cave that could protect bio/organic compounds would preclude the need for risky drilling on Mars. Craters of the Moon National Monument (COM) offers an opportunity to study caves in Holocene iron-rich basalt flows to characterize secondary mineral deposits and search for organic compounds associated with secondary minerals; COM basalts are a good analog for martian basalts because of their high iron but other elements are higher at COM than on Mars. The Blue Dragon flow (~2.1 ka) contains the majority of the accessible caves and lava tubes. Two types of secondary mineral deposits were observed in these caves: ceiling coatings and crack or floor precipitates. Hematite, silica, and calcite comprise ceiling coatings. The crack and floor precipitates are white, efflorescent deposits in cavities along cave walls and ceilings or in localized mounds on cave floors. The secondary minerals in crack and floor precipitates are mainly thenardite and mirabilite with some minor concentrations of trona and/or burkeite. Organic compounds were found associated with the efflorescent deposits. Formation of the deposits is likely due to chemical leaching of basalt by meteoritic water. To test this, fluids collected from the ceiling and walls of the caves were analyzed. Solutions were modeled with the geochemical code, PHREEQC. The model tracked composition as water evaporated. Selected minerals were allowed to precipitate as they became oversaturated. Among the first minerals to become oversaturated were quartz and calcite, which are observed in ceiling deposits. Iron

  1. Radon Concentration in Caves of Croatia - Assesing Effective Radon Doses for Occupational Workers and Visitors

    International Nuclear Information System (INIS)

    Radolic, V.; Miklavcic, I.; Poje, M.; Stanic, D.; Vukovic, B.; Paar, D.

    2011-01-01

    Radon monitoring at potentially highly radioactive location such as caves is important to assess the radiological hazards to occupational workers and occasional visitors. In its Publication 65 the ICRP has produced recommendations dealing with exposure to elevated background radiation, in particular, the risk associated with the inhalation of radon and radon progeny. Recommended annual effective dose from radon 222Rn and its short-lived progeny for workers should not exceed 20 mSv and for occasional users (visitors) the same recommendation is 1 mSv. Measurements were performed with series of track etched detectors (LR115 - type II) in several caves in Croatia. The obtained values for the radon concentration ranged from ambient values up to several thousand Bq m -3 . Radon concentration was measured in about 20 caves of Velebit and Zumberak mountains and the highest radon concentration was in Lubuska jama (3.8 kBq m -3 ) and cave Dolaca (21.8 kBq m -3 ), respectively. Djurovica cave is especially interesting because of its huge tourist potential due to its location bellow Dubrovnik airport. Its mean annual radon concentration of 17.6 kBq m -3 classifies Djurovica cave among caves with high radon concentration. A visitor during half an hour visit at summer time would receive an effective dose of 30.6 μSv. Calculated mean dose rate of 44 μSv/h means that workers (mainly tourist guides) should limit their time inside cave to 454 hours per year. Manita pec is the only cave open for tourists on the territory of Paklenica National Park. The preliminary radon measurements performed during summer 2010, gave an average radon concentration of 1.1 kBq m -3 . An exposure to average dose rate of 3.7 μSv/h means that the tourist guides would receive an effective dose of 0.42 mSv during summer period according to their working schedule. A visitor during half an hour visits would receive an effective dose of 1.86 μSv. (author)

  2. Near Surface Geophysical Methods Applied to the Rising Star Cave System

    Science.gov (United States)

    Webb, S. J.; Naidoo, M.; Elliott, M. C.; Kruger, A.; Roberts, E.; Dirks, P.

    2017-12-01

    The Rising Star Cave system is located approximately 40 km northwest of Johannesburg in the Malmani dolomites (Chuniespoort group,Transvaal Supergroup). The cave system is extensive with 4 km of mapped passages and chambers. The Dinaledi chamber, host to the Homo Naledi fossils, is reached by following a tortuous route with squeezes as small as 20 cm. The chamber is located 30 m below surface and 80 m from the entrance. The enigmatic find of fossils from at least 15 individual hominins, without the presence of other species, led to the idea of deliberate burial. The present access route is difficult and it is unclear how early hominins were able to navigate it, prompting the suggestion of an undiscovered entrance. We are using near surface geophysical methods to investigate possible connections between the surface and the caves. Using a Geometrics Cs-vapor Walkmag, we collected preliminary ground magnetic intensity measurements over a region 300 m x 200 m, using 1 m station spacing and 10 m line spacing. The average magnetic variation along line is 200 nT. We also collected over 100 susceptibility measurements on outcropping lithologies, surface soil and cave sediments using a SM-30 susceptibility meter. The surface soil was one to two orders of magnitude higher than surrounding lithologies (average = 1.5 x 10-3 SI) and the cave sediment samples were slightly higher (average = 3.07 x 10-3 SI). We were able to collect GPR data (GSSI SIR-3000, 400 MHz) in selected spots on the cave floor with the goal of locating the cave floor beneath the sediments. Dolomites usually have low magnetic susceptibilities, but erosion products of the nearby magnetic Hospital Hill or Rooihoogte shales may have been transported into or onto the cave system. This is a likely cause of the magnetic anomalies and larger amplitude anomalies may indicate an accumulation of sediments, extending to depth. These anomalies will be further investigated using gravity to determine if there are

  3. X-ray analysis of aerosol samples from a therapeutic cave

    Energy Technology Data Exchange (ETDEWEB)

    Alfoeldy, B. E-mail: alfi@sunserv.kfki.hu; Toeroek, Sz.; Kocsonya, A.; Szokefalvi-Nagy, Z.; Balla, Md.I

    2001-04-01

    Cave therapy is an efficient therapeutic method to cure asthma, the exact healing effect, however, is not clarified, yet. This study is motivated by the basic assumption that aerosols do play the key role in the cave therapy. This study is based on measurements of single aerosol particles originating from a therapeutic cave of Budapest, Hungary (Szemlohegyi cave). Aerosol particles have been collected in the regions arranged for the therapeutic treatment. Samples were further analysed for chemical and morphological aspects, determining the particle size distribution and classifying them according to elemental composition. Three particle classes have been detected based on major element concentration: alumino-silicate, quartz and calcium carbonate. Calcium ions have well-known physiological influence: anti-spastic, anti-inflammation and excretion reducing effects. Inflammation, accompanying spasm and extreme excretion production cause the smothering stigma, the so-called asthma. Therefore it could be assumed that calcium ions present in high concentration in the cave's atmosphere is the major cause of the healing effect.

  4. Bomb-spike dating of a mummified baboon in Ludwig Cave, Namibia

    Directory of Open Access Journals (Sweden)

    Hodgins Greg

    2007-01-01

    Full Text Available In 1982 a mummified adult female baboon was discovered on a ledge in Ludwig Cave in Namibia. A toe bone was removed for dating in July 1995. AMS radiocarbon dating of bone collagen, tendon, and skin indicates a post-modern age. Application of the atomic bomb-spike calibration curve suggests death in late 1977 and an age at death of around 19 years. Baboons roost in the cave and the mummified female, along with a mummified juvenile male discovered in 2002 and three rotting corpses discovered in 1995, were probably chased by other baboons or by leopards down a ca. 6 m drop during the rainy season, and were unable to climb the steep and very slippery slope to escape. The large number of baboons trapped in the cave in less than 20 years, and mummification of two individuals on dry, dusty ledges in the cave, may explain why large numbers of baboon skeletons have been discovered in ancient bone breccias (up to 4 Ma old in a number of caves throughout Southern Africa.

  5. Hearth-side socioeconomics, hunting and paleoecology during the late Lower Paleolithic at Qesem Cave, Israel.

    Science.gov (United States)

    Stiner, Mary C; Gopher, Avi; Barkai, Ran

    2011-02-01

    The late Lower Paleolithic archaeofaunas of Qesem Cave in the southern Levant span 400-200 ka and associate with Acheulo-Yabrudian (mainly Amudian) industries. The large mammals are exclusively Eurasian in origin and formed under relatively cool, moist conditions. The zooarchaeological findings testify to large game hunting, hearth-centered carcass processing and meat sharing during the late Lower Paleolithic, not unlike the patterns known from Middle and Upper Paleolithic caves in the region. Well-defined hearth features are rarely preserved in Qesem Cave, but the heterogeneous distributions of burned bones indicate areas of frequent hearth rebuilding throughout the occupation sequence. The hominins delayed consumption of high quality body parts until they could be moved to the cave, where hearths were hubs of processing activities and social interaction. Paradoxically, the cut marks on the Qesem bones are both more abundant and more randomly oriented than those observed in Middle and Upper Paleolithic cases in the Levant. These results suggest that several individuals were directly involved in cutting meat from the bones and that the social mechanics of meat sharing during the late Lower Paleolithic at Qesem Cave differed from those typical of both the Middle and Upper Paleolithic in the region. Copyright © 2010 Elsevier Ltd. All rights reserved.

  6. Passive seismic tomography application for cave monitoring in DOZ underground mine PT. Freeport Indonesia

    International Nuclear Information System (INIS)

    Nurhandoko, Bagus Endar B.; Wely, Woen; Setiadi, Herlan; Riyanto, Erwin

    2015-01-01

    It is already known that tomography has a great impact for analyzing and mapping unknown objects based on inversion, travel time as well as waveform inversion. Therefore, tomography has used in wide area, not only in medical but also in petroleum as well as mining. Recently, tomography method is being applied in several mining industries. A case study of tomography imaging has been carried out in DOZ ( Deep Ore Zone ) block caving mine, Tembagapura, Papua. Many researchers are undergoing to investigate the properties of DOZ cave not only outside but also inside which is unknown. Tomography takes a part for determining this objective.The sources are natural from the seismic events that caused by mining induced seismicity and rocks deformation activity, therefore it is called as passive seismic. These microseismic travel time data are processed by Simultaneous Iterative Reconstruction Technique (SIRT). The result of the inversion can be used for DOZ cave monitoring. These information must be used for identifying weak zone inside the cave. In addition, these results of tomography can be used to determine DOZ and cave information to support mine activity in PT. Freeport Indonesia

  7. Digital Preservation of Ancient Maya Cave Architecture: Recent Field Efforts in Quintana Roo, Mexico

    Science.gov (United States)

    Rissolo, D.; Lo, E.; Hess, M. R.; Meyer, D. E.; Amador, F. E.

    2017-08-01

    The presence of ancient Maya shrines in caves serves as unequivocal evidence for the ritual appropriation of these subterranean spaces and their significance with respect to Maya religious practice. Detailed study of the miniature masonry temples and altar features in the caves of Quintana Roo, Mexico reveals a strong stylistic and likely functional correspondence between these structures and their terrestrial counterparts at Postclassic sites. The Proyecto Arquitectura Subterranea de Quintana Roo (coordinated by the Center of Interdisciplinary Science for Art, Architecture, and Archaeology, or CISA3, at the University of California, San Diego and in collaboration with the Instituto Nacional de Antropologia e Historia in Mexico) is conducting a survey and program of digital documentation of both the pristine and impacted cave shrines of the region. Once an area is developed and populated, and access is opened to caves containing ancient architectural features, they are soon vandalized - often resulting in the complete obliteration of these rare miniature buildings and their diagnostic architectural elements. This emergent situation necessitates the use of rapid reality-capture tools; however, the physical challenges of working in caves requires researchers of adapt increasingly common architectural documentation methodologies to more adverse field conditions.

  8. Microbial communities in a coastal cave: Cova des Pas de Vallgornera (Mallorca, Western Mediterranean

    Directory of Open Access Journals (Sweden)

    Antoni Busquets

    2014-05-01

    Full Text Available As a part of an ongoing project on the role of microbes in the biogeochemistry of Majorcan caves, the species diversity of microbial communities present in cave pools of anchialine waters in the Cova des Pas de Vallgornera (Mallorca, western Mediterranean is investigated by a culture-dependent method. Two-hundred and forty-eight strains isolated from this characteristic cave environment of the littoral karst are identified by whole-cell-MALDI-TOF mass spectrometry and phylogeneticaly by 16S rRNA gene sequences. Total cell counts and species diversity of the bacterial communities decreas with the distance to the entrance of the cave and to the sea. Strains are mainly identified as members of the Gammaproteobacteria and Actinobacteria. Around 20% of the isolates are able to precipitate carbonates. Calcite is the predominant phase, growing in all the precipitates, although struvite is also found in one Pseudomonas and in one Aspergillus cultures. Differences in crystal characteristics of external shape (habit and growth are observed according to the bacterial species promoting the precipitates. Bacteria associated with multicolored ferromanganese deposits, present in several parts of the cave, are also studied and are identified as Pseudomonas benzenivorans and Nocardioides luteus. The preponderance of Pseudomonas species and the possible contribution of bacteria in calcite deposition are discussed.

  9. Cova des Pas de Vallgornera, (Mallorca, Spain: history of exploration and cave description

    Directory of Open Access Journals (Sweden)

    Antoni Merino

    2014-05-01

    Full Text Available The Cova des Pas de Vallgornera lies in the Llucmajor municipality, in southern Mallorca, and is the longest cave in the Balearic Islands. Currently its surveyed length is over 74,000 metres, including more than 17,000 of underwater extensions. The cave was discovered accidentally in 1968, but it was in 2004 when a major breakthrough shed light on its real extension and importance. The cave roughly shows two tiers of passages, apart from the underwater extensions, the first one is between 7 and 11 m above the mean sea level, the second one is about at the water table level. The importance of the cave is not only related to its extension, but also to the presence of a wide variety of speleothems and outstanding solutional morphologies that evidence a complex evolution. The cave is under the protection of Conselleria de Medi Ambient, Govern de les Illes Balears (the Regional Environmental Authority and was declared Site of Community Importance, within the Natura 2000 Network

  10. Cooperative hunting and meat sharing 400-200 kya at Qesem Cave, Israel.

    Science.gov (United States)

    Stiner, Mary C; Barkai, Ran; Gopher, Avi

    2009-08-11

    Zooarchaeological research at Qesem Cave, Israel demonstrates that large-game hunting was a regular practice by the late Lower Paleolithic period. The 400- to 200,000-year-old fallow deer assemblages from this cave provide early examples of prime-age-focused ungulate hunting, a human predator-prey relationship that has persisted into recent times. The meat diet at Qesem centered on large game and was supplemented with tortoises. These hominins hunted cooperatively, and consumption of the highest quality parts of large prey was delayed until the food could be moved to the cave and processed with the aid of blade cutting tools and fire. Delayed consumption of high-quality body parts implies that the meat was shared with other members of the group. The types of cut marks on upper limb bones indicate simple flesh removal activities only. The Qesem cut marks are both more abundant and more randomly oriented than those observed in Middle and Upper Paleolithic cases in the Levant, suggesting that more (skilled and unskilled) individuals were directly involved in cutting meat from the bones at Qesem Cave. Among recent humans, butchering of large animals normally involves a chain of focused tasks performed by one or just a few persons, and butchering guides many of the formalities of meat distribution and sharing that follow. The results from Qesem Cave raise new hypotheses about possible differences in the mechanics of meat sharing between the late Lower Paleolithic and Middle Paleolithic.

  11. Passive seismic tomography application for cave monitoring in DOZ underground mine PT. Freeport Indonesia

    Energy Technology Data Exchange (ETDEWEB)

    Nurhandoko, Bagus Endar B.; Wely, Woen; Setiadi, Herlan [WISFIR Laboratory, Earth Physics and Complex System Division, Physics Department, Faculty of Mathematics and Natural Sciences, Institut Teknologi Bandung (Indonesia); Riyanto, Erwin [Geotechnical and Hydrology PT. Freeport Indonesia wonbin-ww@hotmail.com (Indonesia)

    2015-04-16

    It is already known that tomography has a great impact for analyzing and mapping unknown objects based on inversion, travel time as well as waveform inversion. Therefore, tomography has used in wide area, not only in medical but also in petroleum as well as mining. Recently, tomography method is being applied in several mining industries. A case study of tomography imaging has been carried out in DOZ ( Deep Ore Zone ) block caving mine, Tembagapura, Papua. Many researchers are undergoing to investigate the properties of DOZ cave not only outside but also inside which is unknown. Tomography takes a part for determining this objective.The sources are natural from the seismic events that caused by mining induced seismicity and rocks deformation activity, therefore it is called as passive seismic. These microseismic travel time data are processed by Simultaneous Iterative Reconstruction Technique (SIRT). The result of the inversion can be used for DOZ cave monitoring. These information must be used for identifying weak zone inside the cave. In addition, these results of tomography can be used to determine DOZ and cave information to support mine activity in PT. Freeport Indonesia.

  12. Cave development in an uplifting fold-and-thrust belt of the Tatra Mountains, Poland

    Directory of Open Access Journals (Sweden)

    Jacek Szczygiel

    2015-09-01

    Full Text Available Detailed structural analysis and geomorphological observations supplemented by the analysis of the distribution of karst conduit directions have been performed in 23 morphologically diverse caves in the Tatra Mountains. Based on these studies, a development scheme of vadose cave passages has been proposed for the most common geological settings in the fold-and-thrust-belt: (1 single-plain faults, (2 multiple fault cores, (3 bedding plane fractures and (4 hinge zones of recumbent folds. Results indicate that the dynamics of the massif (local gravity sliding in the nearby slope zone and regional stress fields, along with the structural pattern, influences the predisposition of structural and stratigraphic discontinuities to karst drainage. Constant tectonic stress fields affected the massif during the entire speleogenesis. This led to the rejuvenation of the same displacements in successive tectonic events, which resulted in promoting this reactivated structures in successive speleogenetic phases. Structures along which older cave levels had developed were also utilized later by vadose and phreatic drainage, leading to the intersection of the vadose passages with elevated paleo-phreatic cave levels. Independently, formation of entirely vadose caves, guided by the same group of weak and rejuvenated planes, was enabled. In the Tatras, the concentric and recumbent geometry of the main folds resulted in steep dipping of the bedding planes over a distance up to a few hundred meters which makes the bedding plane fractures subject to karst water circulation in these geologic and geodynamic settings.

  13. A clustering approach applied to time-lapse ERT interpretation - Case study of Lascaux cave

    Science.gov (United States)

    Xu, Shan; Sirieix, Colette; Riss, Joëlle; Malaurent, Philippe

    2017-09-01

    The Lascaux cave, located in southwest France, is one of the most important prehistoric cave in the world that shows Paleolithic paintings. This study aims to characterize the structure of the weathered epikarst setting located above the cave using Time-Lapse Electrical Resistivity Tomography (ERT) combined with local hydrogeological and climatic environmental data. Twenty ERT profiles were carried out for two years and helped us to record the seasonal and spatial variations of the electrical resistivity of the hydraulic upstream area of the Lascaux cave. The 20 interpreted resistivity models were merged into a single synthetic model using a multidimensional statistical method (Hierarchical Agglomerative Clustering). The individual blocks from the synthetic model associated with a similar resistivity variability were gathered into 7 clusters. We combined the resistivity temporal variations with climatic and hydrogeological data to propose a geo-electrical model that relates to a conceptual geological model. We provide a geological interpretation for each cluster regarding epikarst features. The superficial clusters (no 1 & 2) are linked to effective rainfall and trees, probably a fractured limestone. Another two clusters (no 6 & 7) are linked to detrital formations (sand and clay respectively). The cluster 3 may correspond to a marly limestone that forms a non-permeable horizon. Finally, the electrical behavior of the last two clusters (no 4 & 5) is correlated with the variation of flow rate; they may be a privileged feed zone of the flow in the cave.

  14. DIGITAL PRESERVATION OF ANCIENT MAYA CAVE ARCHITECTURE: RECENT FIELD EFFORTS IN QUINTANA ROO, MEXICO

    Directory of Open Access Journals (Sweden)

    D. Rissolo

    2017-08-01

    Full Text Available The presence of ancient Maya shrines in caves serves as unequivocal evidence for the ritual appropriation of these subterranean spaces and their significance with respect to Maya religious practice. Detailed study of the miniature masonry temples and altar features in the caves of Quintana Roo, Mexico reveals a strong stylistic and likely functional correspondence between these structures and their terrestrial counterparts at Postclassic sites. The Proyecto Arquitectura Subterranea de Quintana Roo (coordinated by the Center of Interdisciplinary Science for Art, Architecture, and Archaeology, or CISA3, at the University of California, San Diego and in collaboration with the Instituto Nacional de Antropologia e Historia in Mexico is conducting a survey and program of digital documentation of both the pristine and impacted cave shrines of the region. Once an area is developed and populated, and access is opened to caves containing ancient architectural features, they are soon vandalized – often resulting in the complete obliteration of these rare miniature buildings and their diagnostic architectural elements. This emergent situation necessitates the use of rapid reality-capture tools; however, the physical challenges of working in caves requires researchers of adapt increasingly common architectural documentation methodologies to more adverse field conditions.

  15. Geomorphometric analysis of cave ceiling channels mapped with 3-D terrestrial laser scanning

    Science.gov (United States)

    Gallay, Michal; Hochmuth, Zdenko; Kaňuk, Ján; Hofierka, Jaroslav

    2016-05-01

    The change of hydrological conditions during the evolution of caves in carbonate rocks often results in a complex subterranean geomorphology, which comprises specific landforms such as ceiling channels, anastomosing half tubes, or speleothems organized vertically in different levels. Studying such complex environments traditionally requires tedious mapping; however, this is being replaced with terrestrial laser scanning technology. Laser scanning overcomes the problem of reaching high ceilings, providing new options to map underground landscapes with unprecedented level of detail and accuracy. The acquired point cloud can be handled conveniently with dedicated software, but applying traditional geomorphometry to analyse the cave surface is limited. This is because geomorphometry has been focused on parameterization and analysis of surficial terrain. The theoretical and methodological concept has been based on two-dimensional (2-D) scalar fields, which are sufficient for most cases of the surficial terrain. The terrain surface is modelled with a bivariate function of altitude (elevation) and represented by a raster digital elevation model. However, the cave is a 3-D entity; therefore, a different approach is required for geomorphometric analysis. In this paper, we demonstrate the benefits of high-resolution cave mapping and 3-D modelling to better understand the palaeohydrography of the Domica cave in Slovakia. This methodological approach adopted traditional geomorphometric methods in a unique manner and also new methods used in 3-D computer graphics, which can be applied to study other 3-D geomorphological forms.

  16. X-ray analysis of aerosol samples from a therapeutic cave

    International Nuclear Information System (INIS)

    Alfoeldy, B.; Toeroek, Sz.; Kocsonya, A.; Szokefalvi-Nagy, Z.; Balla, Md.I.

    2001-01-01

    Cave therapy is an efficient therapeutic method to cure asthma, the exact healing effect, however, is not clarified, yet. This study is motivated by the basic assumption that aerosols do play the key role in the cave therapy. This study is based on measurements of single aerosol particles originating from a therapeutic cave of Budapest, Hungary (Szemlohegyi cave). Aerosol particles have been collected in the regions arranged for the therapeutic treatment. Samples were further analysed for chemical and morphological aspects, determining the particle size distribution and classifying them according to elemental composition. Three particle classes have been detected based on major element concentration: alumino-silicate, quartz and calcium carbonate. Calcium ions have well-known physiological influence: anti-spastic, anti-inflammation and excretion reducing effects. Inflammation, accompanying spasm and extreme excretion production cause the smothering stigma, the so-called asthma. Therefore it could be assumed that calcium ions present in high concentration in the cave's atmosphere is the major cause of the healing effect

  17. THE STRUCTURE OF SOIL MESOFAUNA AND MACROFAUNA IN GRODA CAVE, GUNUNGKIDUL

    Directory of Open Access Journals (Sweden)

    Andri Prasetyo

    2016-10-01

      The number of soil macrofauna and mesofauna in Groda Cave can be used as an indicator of bats abundance since bat droppings are food for macrofauna and mesofauna soils. The purpose of this study are to determine the community structure of Groda Cave soil macrofauna and mesofauna  and its correlation with the content of N, P, K. The method used is the observation, taking of macrofauna and mesofauna soils using pit fall traps and tool green technique. Testing the N, P, K of the soil was conducted in Balai Pengkajian Teknologi Pertanian (BPTP Yogyakarta. The analysis technique used Shannon diversity index-Wienner, Margaleff wealth index, frequency of attendance of  macrofauna and mesofauna soils and its correlation with N, P, K of the land in Groda Cave. The results obtained are that six families mesofauna and 20 families macrofauna soils with moderate diversity index, the highest wealth index was in the Margaleff lit zone, the frequency of the highest attendance in the light zone is Formicidae (0.12, ie dim zones Isotomidae and Diptera (a brown (0.04 and the dark zone is Gryllacididae (0.05. The correlation showed the more the content of N, P, K, the fewer mesofauna and macrofauna soils were found. The uniqueness found in this study is the discovery of one species of Isotomidae in Groda Cave, which has been considered spreading only in Sulawesi, Sumatera, Bali, Lombok, Ternate and Papua.   Keywords: community structure, mesofauna soil, macrofauna soil, Groda Cave

  18. Computational design of rolling bearings

    CERN Document Server

    Nguyen-Schäfer, Hung

    2016-01-01

    This book comprehensively presents the computational design of rolling bearings dealing with many interdisciplinary difficult working fields. They encompass elastohydrodynamics (EHD), Hertzian contact theory, oil-film thickness in elastohydrodynamic lubrication (EHL), bearing dynamics, tribology of surface textures, fatigue failure mechanisms, fatigue lifetimes of rolling bearings and lubricating greases, Weibull distribution, rotor balancing, and airborne noises (NVH) in the rolling bearings. Furthermore, the readers are provided with hands-on essential formulas based on the up-to-date DIN ISO norms and helpful examples for computational design of rolling bearings. The topics are intended for undergraduate and graduate students in mechanical and material engineering, research scientists, and practicing engineers who want to understand the interactions between these working fields and to know how to design the rolling bearings for automotive industry and many other industries.

  19. Molecular phylogeography of the brown bear (Ursus arctos) in Northeastern Asia based on analyses of complete mitochondrial DNA sequences.

    Science.gov (United States)

    Hirata, Daisuke; Mano, Tsutomu; Abramov, Alexei V; Baryshnikov, Gennady F; Kosintsev, Pavel A; Vorobiev, Alexandr A; Raichev, Evgeny G; Tsunoda, Hiroshi; Kaneko, Yayoi; Murata, Koichi; Fukui, Daisuke; Masuda, Ryuichi

    2013-07-01

    To further elucidate the migration history of the brown bears (Ursus arctos) on Hokkaido Island, Japan, we analyzed the complete mitochondrial DNA (mtDNA) sequences of 35 brown bears from Hokkaido, the southern Kuril Islands (Etorofu and Kunashiri), Sakhalin Island, and the Eurasian Continent (continental Russia, Bulgaria, and Tibet), and those of four polar bears. Based on these sequences, we reconstructed the maternal phylogeny of the brown bear and estimated divergence times to investigate the timing of brown bear migrations, especially in northeastern Eurasia. Our gene tree showed the mtDNA haplotypes of all 73 brown and polar bears to be divided into eight divergent lineages. The brown bear on Hokkaido was divided into three lineages (central, eastern, and southern). The Sakhalin brown bear grouped with eastern European and western Alaskan brown bears. Etorofu and Kunashiri brown bears were closely related to eastern Hokkaido brown bears and could have diverged from the eastern Hokkaido lineage after formation of the channel between Hokkaido and the southern Kuril Islands. Tibetan brown bears diverged early in the eastern lineage. Southern Hokkaido brown bears were closely related to North American brown bears.

  20. European Commission policies

    International Nuclear Information System (INIS)

    Coldwell, R.

    1993-01-01

    This debate discusses the debate surrounding the proposed European Community (EC) Directive on the completion of the internal energy market for natural gas and electric power. The context in which the liberalisation program is proposed is described for electricity, considering political issues, international ownership patterns and trade between Eastern and Western Europe. The author then argues for Member States to be consistent and fair, bearing in mind existing variations in liberalisation of national energy markets. Finally the components of the directive are examined. The United Kingdom, with its already liberalised electricity industry has much to gain from the Directive, while other countries which oppose it, are seen as protecting the vested interests of their own utilities. (UK)

  1. Grease lubrication in rolling bearings

    CERN Document Server

    Lugt, Piet M

    2012-01-01

    The definitive book on the science of grease lubrication for roller and needle bearings in industrial and vehicle engineering. Grease Lubrication in Rolling Bearings provides an overview of the existing knowledge on the various aspects of grease lubrication (including lubrication systems) and the state of the art models that exist today. The book reviews the physical and chemical aspects of grease lubrication, primarily directed towards lubrication of rolling bearings. The first part of the book covers grease composition, properties and rheology, including thermal

  2. Hydrostatic and hybrid bearing design

    CERN Document Server

    Rowe, W B

    1983-01-01

    Hydrostatic and Hybrid Bearing Design is a 15-chapter book that focuses on the bearing design and testing. This book first describes the application of hydrostatic bearings, as well as the device pressure, flow, force, power, and temperature. Subsequent chapters discuss the load and flow rate of thrust pads; circuit design, flow control, load, and stiffness; and the basis of the design procedures and selection of tolerances. The specific types of bearings, their design, dynamics, and experimental methods and testing are also shown. This book will be very valuable to students of engineering des

  3. European visit

    CERN Multimedia

    2006-01-01

    The European Commissioner for Science and Research, Janez Potočnik, (on the right) visited the CMS assembly hall accompanied by Jim Virdee, Deputy Spokesman of CMS (on the left), and Robert Aymar, Director-General of CERN. The European Commissioner for Science and Research, Janez Potočnik, visited CERN on Tuesday 31 January. He was welcomed by the Director-General, Robert Aymar, who described the missions and current activities of CERN to him, in particular the realisation of the LHC with its three components: accelerator, detectors, storage and processing of data. The European Commissioner then visited the CMS assembly hall, then the hall for testing the LHC magnets and the ATLAS cavern. During this first visit since his appointment at the end of 2004, Janez Potočnik appeared very interested by the operation of CERN, an example of successful scientific co-operation on a European scale. The many projects (30 on average) that CERN and the European Commission carry out jointly for the benefit of res...

  4. Coarsely crystalline cryogenic cave carbonate – a new archive to estimate the Last Glacial minimum permafrost depth in Central Europe

    Czech Academy of Sciences Publication Activity Database

    Žák, Karel; Richter, D. K.; Filippi, Michal; Živor, Roman; Deininger, M.; Mangini, A.; Scholz, D.

    2012-01-01

    Roč. 8, č. 6 (2012), s. 1821-1837 ISSN 1814-9324 R&D Projects: GA ČR GAP210/10/1760 Institutional research plan: CEZ:AV0Z30130516 Keywords : caves * cave carbonate * permafrost * Last Glacial Subject RIV: DB - Geology ; Mineralogy Impact factor: 3.556, year: 2012

  5. Indoor radon concentration levels in Mexican caves, using nuclear track methodology, and the relationship with living habits of the bats

    International Nuclear Information System (INIS)

    Espinosa, G.; Golzarri, J.I.; Vega-Orihuela, E.; Morales-Malacara, J.B.

    2013-01-01

    This work presents the results of a study of the radon levels in four caves in Mexico: Los Riscos Cave and El Judio Cave in the State of Queretaro, and Coyozochico Cave and Karmidas Cave in the State of Puebla. The measurements were made using the passive closed-end cup system, with CR-39 (Lantrack R ) as detection material, and following protocols established for the measurement of indoor radon, developed at the Dosimetry Applications Project of the Physics Institute of the Universidad Nacional Autonoma de Mexico. The radon concentration at one location with Karmidas Cave reached more than 60,000 Bq/m 3 , while concentrations in the other three caves varied from 83.1-1216.0 Bq/m 3 , was found. During the study was observed an interesting coincidence between the radon concentration distribution inside the caves, and the bat colonies location. In general, the bat colonies are located at the medium or low radon concentration levels zones. (author)

  6. European hadrons

    International Nuclear Information System (INIS)

    Anon.

    1986-01-01

    The European Hadron Facility (EHF) is a project for particle and nuclear physics in the 1990s which would consist of a fast cycling high intensity proton synchrotron of about 30 GeV primary energy and providing a varied spectrum of intense high quality secondary beams (polarized protons, pions, muons, kaons, antiprotons, neutrinos). The physics case of this project has been studied over the last two years by a European group of particle and nuclear physicists (EHF Study Group), whilst the conceptual design for the accelerator complex was worked out (and is still being worked on) by an international group of machine experts (EHF Design Study Group). Both aspects have been discussed in recent years in a series of working parties, topical seminars, and workshops held in Freiburg, Trieste, Heidelberg, Karlsruhe, Les Rasses and Villigen. This long series of meetings culminated in the International Conference on a European Hadron Facility held in Mainz from 10-14 March

  7. Seasonal variation measurements of radon levels in caves using SSNTD method

    International Nuclear Information System (INIS)

    Espinosa, G.; Golzarri, J.I.; Gammage, R.B.; Sajo-Bohus, L.; Viccon-Pale, J.; Signoret-Poillon, M.

    2008-01-01

    The results of radon concentration measurements inside of the Gabriel caves of Mexico, during three consecutive two-month periods covering almost three seasons, are reported in the present work. The radio-ecological importance of this site is related to the radon and its concentration-dynamic behavior in the cave. Further interest in radiation safety motivated this initiative since routine biological field work is done, with people spending long periods of time there. CR-39 passive nuclear track detector was chosen for this survey. Radon concentration levels decrease during the rainy season and show different values depending on the ventilation and geometeorological structure. Measured values range between 956 and 4931Bqm -3 , an indication that radon doses may exceed the allowed values for workers. This project is part of a larger study of indoor radon alpha emitters in Mexican caves

  8. Seasonal variation measurements of radon levels in caves using SSNTD method

    Energy Technology Data Exchange (ETDEWEB)

    Espinosa, G. [Instituto de Fisica, Universidad Nacional Autonoma de Mexico, Apartado Postal 20-364, 01000 Mexico, D.F. (Mexico)], E-mail: espinosa@fisica.unam.mx; Golzarri, J.I. [Instituto de Fisica, Universidad Nacional Autonoma de Mexico, Apartado Postal 20-364, 01000 Mexico, D.F. (Mexico); Gammage, R.B. [Oak Ridge National Laboratory, PO Box 2008, Oak Ridge, TN 37831-6480 (United States); Sajo-Bohus, L. [Departamento de Fisica, Universidad Simon Bolivar (Venezuela); Viccon-Pale, J.; Signoret-Poillon, M. [El Hombre y su Ambiente, UAM-Xochimilco, Mexico D.F. (Mexico)

    2008-08-15

    The results of radon concentration measurements inside of the Gabriel caves of Mexico, during three consecutive two-month periods covering almost three seasons, are reported in the present work. The radio-ecological importance of this site is related to the radon and its concentration-dynamic behavior in the cave. Further interest in radiation safety motivated this initiative since routine biological field work is done, with people spending long periods of time there. CR-39 passive nuclear track detector was chosen for this survey. Radon concentration levels decrease during the rainy season and show different values depending on the ventilation and geometeorological structure. Measured values range between 956 and 4931Bqm{sup -3}, an indication that radon doses may exceed the allowed values for workers. This project is part of a larger study of indoor radon alpha emitters in Mexican caves.

  9. A note on the occurrence of a crayback stalagmite at Niah Caves, Borneo

    Directory of Open Access Journals (Sweden)

    Lundberg Joyce

    2011-01-01

    Full Text Available Crayback stalagmites have mainly been reported from New South Wales, Australia. Here we document a small crayback in the entrance of Painted Cave (Kain Hitam, part of the Niah Caves complex in Sarawak, Borneo. Measuring some 65 cm in length and 18 cm in height, this deposit is elongate in the direction of the dominant wind and thus oriented towards the natural tunnel entrance. It shows the classic humpbacked long profile, made up of small transverse segments or plates, in this case the tail extending towards the entrance. The dark blue-green colour down the centre suggests that cyanobacterial growth follows the track of the wind-deflected roof drip. The dry silty cave sediment provides material for accretion onto the biological mat. This is the only example known from Borneo and one of the very few known from outside of Australia.

  10. Radon continuous monitoring in Altamira Cave (northern Spain) to assess user's annual effective dose

    International Nuclear Information System (INIS)

    Lario, J.; Sanchez-Moral, S.; Canaveras, J.C.; Cuezva, S.; Soler, V.

    2005-01-01

    In this work, we present the values of radon concentration, measured by continuous monitoring during a complete annual cycle in the Polychromes Hall of Altamira Cave in order to undertake more precise calculations of annual effective dose for guides and visitors in tourist caves. The 222 Rn levels monitored inside the cave ranges from 186 Bq m -3 to 7120 Bq m -3 , with an annual average of 3562 Bq m -3 . In order to more accurately estimate effective dose we use three scenarios with different equilibrium factors (F=0.5, 0.7 and 1.0) together with different dose conversion factors proposed in the literature. Neither effective dose exceeds international recommendations. Moreover, with an automatic radon monitoring system the time remaining to reach the maximum annual dose recommended could be automatically updated

  11. Behaviour of the Pleistocene marsupial lion deduced from claw marks in a southwestern Australian cave.

    Science.gov (United States)

    Arman, Samuel D; Prideaux, Gavin J

    2016-02-15

    The marsupial lion, Thylacoleo carnifex, was the largest-ever marsupial carnivore, and is one of the most iconic extinct Australian vertebrates. With a highly-specialised dentition, powerful forelimbs and a robust build, its overall morphology is not approached by any other mammal. However, despite >150 years of attention, fundamental aspects of its biology remain unresolved. Here we analyse an assemblage of claw marks preserved on surfaces in a cave and deduce that they were generated by marsupial lions. The distribution and skewed size range of claw marks within the cave elucidate two key aspects of marsupial lion biology: they were excellent climbers and reared young in caves. Scrutiny of >10,000 co-located Pleistocene bones reveals few if any marsupial lion tooth marks, which dovetails with the morphology-based interpretation of the species as a flesh specialist.

  12. On some new cave-dwelling ground beetles (Coleoptera: Carabidae: Trechini from eastern Serbia

    Directory of Open Access Journals (Sweden)

    Vrbica Maja

    2013-01-01

    Full Text Available The following new cavernicolous ground beetle taxa are described from three caves in eastern Serbia: Duvalius (Paraduvalius trifunovici sp. n., from the Mandina Pećina Cave, village of Zlot, near Bor, Kučajske Planine Mts., D. (P. rtanjensis sp. n., from the Golema Porica Pit, Mt. Rtanj, and Glabroduvalius gen. n., G. tupiznicensis sp. n., from the Gornja Lenovačka Pećina Cave, village of Lenovac, near Zaječar, Mt. Tupižnica. The new taxa are easily distinguished from related organisms. All important morphological features have been listed, along with the diagnoses and illustrations of the taxa. The new taxa are relicts and endemics of eastern Serbia and probably belong to old phyletic lineages of Tertiary or even pre-Tertiary origin. [Projekat Ministarstva nauke Republike Srbije, br. 173038, br. 43001 i br. 43002

  13. U-series dating and stable isotope records of speleothem records from the Scladina Cave (Belgium)

    Science.gov (United States)

    van der Lubbe, Jeroen; Bonjean, Dominique; Hellstrom, John; Verheyden, Sophie; Vonhof, Hubert

    2015-04-01

    The Scladina cave, situated in the village of Sclayn (Ardennes, Belgium) at the southern bank of the Meuse, is famous for its Neanderthal fossils and artefacts. The infilling of the cave consists of a succession of flowstone layers interbedded with reworked loess sediment from outside the cave. The younger flowstone layers correspond to interglacials MIS 5 and the Holocene, while the reworked loess sediments represent cooler conditions. By careful diagenetic screening, well-preserved speleothem material was selected for U-series dating and stable isotope analysis of calcite and fluid inclusions. The results provide important new constraints on the age of Neanderthal fossils and artefacts, and bracket the time periods with a hydroclimate favorable for speleothem growth. The combination of fluid inclusion and calcite isotope analysis documents climate variability in the interglacials at high temporal resolution.

  14. More than horse paintings in Ekain Cave (Deba, Gipuzkoa: Palaeolithic digital engravings in Western Europe

    Directory of Open Access Journals (Sweden)

    Blanca Ochoa

    2018-06-01

    Full Text Available Technological advances are enabling the discovery of new caves with rock art and of new graphic units in already known and studied caves. In this framework, a discovery was made in an unexplored gallery in Ekain (Deba, Gipuzkoa, a small passage named La Fontana. Figurative representations (horses and non-figurative marks (simple strokes were traced on both walls using digital engraving on decalcified clay. This discovery prompted the re-study of depictions executed with the same technique in the final part of Azkenzaldei gallery, where a new ensemble of representations, mostly non-figurative, was also found. Since it is impossible to date these representations directly, we apply a stylistic analysis to establish their chronology. The comparison with other depictions in the same cave might point towards their execution during advanced phases of the Magdalenian.

  15. Seasonal variations of {sup 14}C and δ{sup 13}C for cave drip waters in Ryugashi Cave, Shizuoka Prefecture, central Japan

    Energy Technology Data Exchange (ETDEWEB)

    Minami, Masayo, E-mail: minami@nendai.nagoya-u.ac.jp [Center for Chronological Research, Nagoya University, Nagoya 464-8602 (Japan); Kato, Tomomi [Graduate School of Environmental Studies, Nagoya University, Nagoya 464-8601 (Japan); Horikawa, Keiji [Department of Environmental Biology and Chemistry, Toyama University, Toyama 930-8555 (Japan); Nakamura, Toshio [Center for Chronological Research, Nagoya University, Nagoya 464-8602 (Japan)

    2015-11-01

    Speleothem {sup 14}C has recently emerged as a potentially powerful proxy for hydrology changes in comparison with atmospheric {sup 14}C calibration curve, rather than as a direct dating tool, apart from a time marker using bomb peak of {sup 14}C. Some possible causes for the relationship between speleothem {sup 14}C content (or dead carbon fraction: DCF) and karst hydrology have been proposed, such as changes in temperature, precipitation, drip water flow dynamics, cave air ventilation, soil air pCO{sub 2}. In this study, we investigated seasonal variation in {sup 14}C and δ{sup 13}C of drip water in Ryugashi Cave, Shizuoka Prefecture, central Japan, to examine the causes of the {sup 14}C and δ{sup 13}C variations in a speleothem. The results show that different {sup 14}C concentrations and δ{sup 13}C values of drip water from the Ryugashi Cave, were exhibited at different sites of the Caves No. 1, No. 3, and No. 4, which have different temperature, air pCO{sub 2}, and flow paths. Further, the {sup 14}C and δ{sup 13}C of drip waters showed seasonal variations at all sites, which were lower in fall and winter, and higher in spring and summer, though the extent of the variations was different among the sites. The {sup 14}C in drip waters tended to be correlated with the drip rates: {sup 14}C tended to be higher in drip waters with higher drip rates, and also correlated with rainfall amount around the Ryugashi Cave, especially for the drip waters in Cave No. 3, which are considered to have simpler flow paths. The increase in rainfall amount could bring the increase in drip rate of drip water, and then the decrease in interaction between solution and karst, resulting in {sup 14}C increase (DCF decrease) in drip water. Accordingly, the reconstruction of precipitation could be performed using {sup 14}C variation in a speleothem formed by drip water with simple flow dynamics.

  16. Geochemical characteristics of cave drip water respond to ENSO based on a 6-year monitoring work in Yangkou Cave, Southwest China

    Science.gov (United States)

    Chen, Chao-Jun; Li, Ting-Yong

    2018-06-01

    The scientific explanation of speleothem δ18O in Chinese monsoon region is a greatly debated issue. Modern cave monitoring combined with instrument observation maybe is an essential solution to deal with this issue. During the period from 2011 to 2016, we monitored local precipitation, soil water in three soil profiles, and six drip water sites in Yangkou Cave, which is located in Chongqing City, Southwest China. This article presents measurements about δ18O, δD and Mg/Ca ratios of drip water and compared these geochemical proxies with contemporaneous atmospheric circulations. The main conclusions are: (1) As water migrates from precipitation to soil water to cave drip water, the amplitudes of seasonal variations in δD and δ18O decreased gradually. Due to the existence of complex hydrogeological conditions, the range of variation and the seasonal characteristics of δD and δ18O differ among the drip sites where samples were collected, but the interannual variability is nearly the same. The drip water Mg/Ca ratios are mainly regulated by changes in hydrological conditions in the epikarst zone, with higher values during winter months than that during summer months. (2) When an El Niño event occurs, the Western Pacific Subtropical High (WPSH) is migrated westward, and the production of near-source water vapor from the western Pacific and the South China Sea increases, leading to higher δ18O values in the precipitation and the cave drip water. The drip water Mg/Ca ratios were significantly lower with increased summer precipitation. On the other hand, during La Niña events, the WPSH is migrated eastward, and inputs of water vapor that has traveled greater distances (from the Indian Ocean) become comparatively important, resulting in lower δ18O values in the precipitation and the cave drip water. The drip water Mg/Ca ratios were higher with decreased summer precipitation. In summary, the interannual variability of δ18O in the drip waters of Yangkou Cave

  17. Earthquakes as collapse precursors at the Han-sur-Lesse Cave in the Belgian Ardennes

    Science.gov (United States)

    Camelbeeck, Thierry; Quinif, Yves; Verheyden, Sophie; Vanneste, Kris; Knuts, Elisabeth

    2018-05-01

    Collapse activation is an ongoing process in the evolution of karstic networks related to the weakening of cave vaults. Because collapses are infrequent, few have been directly observed, making it challenging to evaluate the role of external processes in their initiation and triggering. Here, we study the two most recent collapses in the Dôme chamber of the Han-sur-Lesse Cave (Belgian Ardenne) that occurred on or shortly after 3rd December 1828 and between the 13th and 14th of March 1984. Because of the low probability that the two earthquakes that generated the strongest ground motions in Han-sur-Lesse since 1800, on 23rd February 1828 (Mw = 5.1 in Central Belgium) and 8th November 1983 (Mw = 4.8 in Liège) occurred by coincidence less than one year before these collapses, we suggest that the collapses are related to these earthquakes. We argue that the earthquakes accelerated the cave vault instability, leading to the collapses by the action of other factors weakening the host rock. In particular, the 1828 collapse was likely triggered by a smaller Mw = 4.2 nearby earthquake. The 1984 collapse followed two months of heavy rainfall that would have increased water infiltration and pressure in the rock mass favoring destabilization of the cave ceiling. Lamina counting of a stalagmite growing on the 1828 debris dates the collapse at 1826 ± 9 CE, demonstrating the possibility of dating previous collapses with a few years of uncertainty. Furthermore, our study opens new perspectives for studying collapses and their chronology both in the Han-sur-Lesse Cave and in other karstic networks. We suggest that earthquake activity could play a stronger role than previously thought in initiating cave collapses.

  18. Detection of abandoned mines/caves using airborne LWIR hyperspectral data

    Science.gov (United States)

    Shen, Sylvia S.; Roettiger, Kurt A.

    2012-09-01

    The detection of underground structures, both natural and man-made, continues to be an important requirement in both the military/intelligence and civil communities. There are estimates that as many as 70,000 abandoned mines/caves exist across the nation. These mines represent significant hazards to public health and safety, and they are of concern to Government agencies at the local, state, and federal levels. NASA is interested in the detection of caves on Mars and the Moon in anticipation of future manned space missions. And, the military/ intelligence community is interested in detecting caves, mines, and other underground structures that may be used to conceal the production of weapons of mass destruction or to harbor insurgents or other persons of interest by the terrorists. Locating these mines/caves scattered over millions of square miles is an enormous task, and limited resources necessitate the development of an efficient and effective broad area search strategy using remote sensing technologies. This paper describes an internally-funded research project of The Aerospace Corporation (Aerospace) to assess the feasibility of using airborne hyperspectral data to detect abandoned cave/mine entrances in a broad-area search application. In this research, we have demonstrated the potential utility of using thermal contrast between the cave/mine entrance and the ambient environment as a discriminatory signature. We have also demonstrated the use of a water vapor absorption line at12.55 μm and a quartz absorption feature at 9.25 μm as discriminatory signatures. Further work is required to assess the broader applicability of these signatures.

  19. Fast reactor fuel reprocessing plant D1206: disassembly cave window 4 replacement

    International Nuclear Information System (INIS)

    Sutherland, H.G.; Beckitt, S.; Potts, A.B.

    1996-01-01

    At UKAEA's fast reactor reprocessing plant at Dounreay, the containment glass on the zinc bromide cave viewing window tank failed after 13 years active use. External shielding was fitted and the window tank subsequently drained to make it safe. Fuel cropping operations carried out behind the window were resited to enable cave work to continue whilst a project team made arrangements and plans to replace the damaged window. Because of the complexity of the task and high (alpha, beta, gamma and neutron) radiation levels in excess of 500 Sv/hr a rehearsal facility was built to develop the remote handling techniques to be employed in the task. (UK)

  20. First record of a cave species of Euscorpiops Vachon from Viet Nam (Scorpiones, Euscorpiidae, Scorpiopinae).

    Science.gov (United States)

    Lourenço, Wilson R; Pham, Dinh-Sac

    2013-07-01

    Euscorpiops cavernicola sp. n., belonging to the family Euscorpiidae Laurie, is described on the basis of two male and two female specimens collected in the Hua Ma cave located in the Quang Khe commune, Ba Be district of Bac Kan province in Viet Nam. The new species presents most features exhibited by scorpions within the genus Euscorpiops, however it may represent the first discovered Scorpiopinae species exhibiting certain adaptations to cave life. Copyright © 2013 Académie des sciences. Published by Elsevier SAS. All rights reserved.

  1. The materiality of dung: the manipulation of dung in Neolithic Mediterranean caves

    Directory of Open Access Journals (Sweden)

    Dimitrij Mlekuž

    2009-12-01

    Full Text Available This paper discusses the formation of layers of burnt herbivore dung in Neolithic, Eneolithic and Bronze Age Mediterranean caves. While these layers are clearly connected with transhumant pastoralism and the practice of keeping herds in the caves, their formation should not be seen as the result of purely practical and ‘rational’ reasons. In this paper, I develop an argument that they are remnants of a complex manipulation of substances which includes burning dung to make white ash. Thus instead of seeing dung as a culturally neutral refuse which has to be disposed of, we might see its burning and deposition as the cultural manipulation of potent substance.

  2. Microbially induced iron precipitation associated with a neutrophilic spring at Borra Caves, Vishakhapatnam, India.

    Science.gov (United States)

    Baskar, Sushmitha; Baskar, Ramanathan; Thorseth, Ingunn H; Ovreås, Lise; Pedersen, Rolf B

    2012-04-01

    The present investigation uncovers various pieces of evidence for the possible biologically induced mineralization in iron mats associated with a pH-neutral spring in the Borra caves, Vishakhapatnam, India. Electron microscopy [scanning electron microscopy (SEM) and transmission electron microscopy (TEM)] demonstrated large numbers of (i) hollow tubes (diameter ∼1 μm) resembling sheaths of the iron-oxidizing bacteria Leptothrix, (ii) thin (diameter springs. Understanding biogenic iron oxides in caves has important astrobiological applications as it provides a potential tool for the detection of extraterrestrial life.

  3. Comparative study of acetylcholinesterase and glutathione S-transferase activities of closely related cave and surface Asellus aquaticus (Isopoda: Crustacea.

    Directory of Open Access Journals (Sweden)

    Anita Jemec

    Full Text Available The freshwater isopod crustacean Asellus aquaticus has recently been developed as an emerging invertebrate cave model for studying evolutionary and developmental biology. Mostly morphological and genetic differences between cave and surface A. aquaticus populations have been described up to now, while scarce data are available on other aspects, including physiology. The purpose of this study was to advance our understanding of the physiological differences between cave A. aquaticus and its surface-dwelling counterparts. We sampled two surface populations from the surface section of the sinking Pivka River (central Slovenia, Europe, i.e. locality Pivka Polje, and locality Planina Polje, and one cave population from the subterranean section of the sinking Pivka River, i.e. locality Planina Cave. Animals were sampled in spring, summer and autumn. We measured the activities of acetylcholinesterase (AChE and glutathione S-transferase (GST in individuals snap-frozen in the field immediately after collection. Acetylcholinesterase is likely related to animals' locomotor activity, while GST activity is related to the metabolic activity of an organism. Our study shows significantly lower AChE and GST activities in the cave population in comparison to both surface A. aquaticus populations. This confirms the assumption that cave A. aquaticus have lower locomotor and metabolic activity than surface A. aquaticus in their respective natural environments. In surface A. aquaticus populations, seasonal fluctuations in GST activity were observed, while these were less pronounced in individuals from the more stable cave environment. On the other hand, AChE activity was generally season-independent in all populations. To our knowledge, this is the first study of its kind conducted in A. aquaticus. Our results show that among closely related cave and surface A. aquaticus populations also physiological differences are present besides the morphological and genetic

  4. Superconducting bearings for flywheel applications

    Energy Technology Data Exchange (ETDEWEB)

    Abrahamsen, Asger Bech

    2001-05-01

    A literature study on the application of superconducting bearings in energy storage flywheel systems. The physics of magnetic levitation and superconductors are presented in the first part of the report, followed by a discussion of the literature found on the applications of superconducting bearings in flywheels. (au)

  5. Superconducting bearings for flywheel applications

    DEFF Research Database (Denmark)

    Abrahamsen, A.B.

    2001-01-01

    A literature study on the application of superconducting bearings in energy storage flywheel systems. The physics of magnetic levitation and superconductors are presented in the first part of the report, followed by a discussion of the literature found onthe applications of superconducting bearings...

  6. New directional archeomagnetic data of burned cave sediments from Switzerland and geomagnetic field variations in Central Europe

    Science.gov (United States)

    Kapper, K. L.; Donadini, F.; Mauvilly, M.; Panovska, S.; Hirt, A. M.

    2014-08-01

    This paper presents new directional archeomagnetic data from nine Meso-/Neolithic fireplaces, sampled in a cave shelter, at Arconciel, in western Switzerland. Rock magnetic measurements indicate a homogenous magnetic mineralogy in all fireplaces, with magnetite as the main magnetic carrier. The remanent magnetization is stable and generally shows one characteristic directional component. Nine new directions, which were obtained from Arconciel, are combined with 356 other archeomagnetic data from a circular area with a radius of 700 km around this site, to obtain a penalized least square spline fit for the past 9000 yr. We found in general good agreement with other local compilations, such as the Balkan curve, the regional SCHA.DIF.8k model and with lake sediments from UK, Fennoscandia and Switzerland. Nevertheless, a time lag of several centuries is observed for a declination maximum between the archeomagnetic spline fit and the other European data records around 5900 BC. This time lag is also observed in the Swiss lake sediment record; therefore we interpret this shift as a local feature of the Earth's magnetic field.

  7. European Cinema

    NARCIS (Netherlands)

    Elsaesser, Thomas

    2005-01-01

    In the face of renewed competition from Hollywood since the early 1980s and the challenges posed to Europe's national cinemas by the fall of the Wall in 1989, independent filmmaking in Europe has begun to re-invent itself. European Cinema: Face to Face with Hollywood re-assesses the different

  8. Space Station alpha joint bearing

    Science.gov (United States)

    Everman, Michael R.; Jones, P. Alan; Spencer, Porter A.

    1987-01-01

    Perhaps the most critical structural system aboard the Space Station is the Solar Alpha Rotary Joint which helps align the power generation system with the sun. The joint must provide structural support and controlled rotation to the outboard transverse booms as well as power and data transfer across the joint. The Solar Alpha Rotary Joint is composed of two transition sections and an integral, large diameter bearing. Alpha joint bearing design presents a particularly interesting problem because of its large size and need for high reliability, stiffness, and on orbit maintability. The discrete roller bearing developed is a novel refinement to cam follower technology. It offers thermal compensation and ease of on-orbit maintenance that are not found in conventional rolling element bearings. How the bearing design evolved is summarized. Driving requirements are reviewed, alternative concepts assessed, and the selected design is described.

  9. Flywheel Challenge: HTS Magnetic Bearing

    International Nuclear Information System (INIS)

    Werfel, F N; Floegel-Delor, U; Riedel, T; Rothfeld, R; Wippich, D; Goebel, B

    2006-01-01

    A 200 mm cylindrical engineering prototype high temperature superconducting (HTS) was designed and fabricated. Measurements show that the 17 kg PM rotor can suspend safely 1000 kg in axial direction and 470 kg radially. The rationale for the bearing performance is to stabilize a 400 kg rotor of a new compact 5 kWh/280 kW flywheel energy storage system (COM - FESS). Measurements of the magnetic bearing force, stiffness and drag-torque are presented indicated the successful targeting a milestone in the HTS bearing technology. The influence of the PM configuration and the YBCO temperature on the bearing performance was experimentally studied, providing high-force or high-stiffness behaviour. The axial stiffness 5 kN/mm at 0.5 mm displacement is the highest value of a HTS bearing we know

  10. An absolutely dated high-resolution stalagmite record from Lianhua Cave in central China: Climate forcing and comparison with Wanxiang Cave and Dongge Cave records over the past 2000 years

    Science.gov (United States)

    Li, Hong-Chun; Yin, Jian-Jun; Shen, Chuan-Chou; Mii, Horng-Sheng; Li, Ting-Yong

    2015-04-01

    A 33-cm long aragonite stalagmite (LHD-1) from Lianhua Cave has been dated by MC-ICPMS 230Th/U method on 41 horizons. Very high U contents (1~6ppm) and low Th contents yield excellent 230Th/U dates which provide reliable chronology of the stalagmite on sub-decadal time scale over the past 3350 years. A total of 1716 samples have been measured for δ18O and δ13C, spanning annual resolution over the past 1820 years. The stalagmite δ18O is not only influenced by the 'amount effect', but also affected by the moisture source. Enhanced the tropical monsoon trough under strong EASM brings higher spring quarter rainfall with isotopically light monsoonal moisture in the cave site, resulting in lighter stalagmite δ18O. On decadal or longer time scales, increased solar activity produces warmer condition and stronger summer monsoon which lead to wet climates. On interannual-to-decadal scales, the Walker Circulation under El Niño conditions during cold periods will shift toward the central Pacific and result in weakening of EASM. Under such a circumstance, dry climates will be prevailed in the study area. Based on the δ18O and δ13C records, we have deciphered climatic and vegetation changes of the study area in decadal scales. The highly precise dated LHD-1 record has been compared with previous published Wanxiang Cave and Dongge Cave records. Although some similarities can be found, there are major discrepancies among the three well-dated records, especially during AD 500-700 and AD 1300-1600. In additional, the major weak monsoon periods defined in the Wanxiang Cave record during late Tang Dynasty, late Yuan Dynasty and late Ming Dynasty are not supported by the LHD-1 record. The heaviest δ18O peaks (more than five continuous heavy values) over the past 2000 years appeared around AD 1990-2003, 1657-1662, 1220-1228, 663-669, 363-370, and 1082-1090 (in the order of heavy to light). None of these periods occurred Chinese dynasty collapse.

  11. Journal bearing impedance descriptions for rotordynamic applications

    NARCIS (Netherlands)

    Childs, D.W.; Moes, H.; Leeuwen, van H.J.

    1977-01-01

    Bearing impedance vectors are introduced for plain journal bearings which define the bearing reaction force components as a function of the bearing motion. Impedance descriptions are developed directly for the approximate Ocvirk (short) and Sommerfeld (long) bearing solutions. The impedance vector

  12. Past surface conditions and speleogenesis as inferred from cave sediments in the Great Cave of Șălitrari Mountain (SW Romania

    Directory of Open Access Journals (Sweden)

    Cristina M. Pușcaș

    2010-08-01

    Full Text Available Abstract In one of the passages in the Great Cave of Șălitrari Mountain the floor is completely covered by an alluvial deposit at least 6 m in thickness, ranging from boulders, and cobbles, to sand and clay, topped by a layer of dry bat guano. Sediment and mineral samples collected from six profiles underwent broad analyses to determine their petrological and mineralogical makeup, grain-size distribution, and paleoclimatic significance. The complicated facies alternation suggests frequent changes in the former stream’s hydrological parameters, with frequent flooding, leading to the hypothesis that the climate was somewhat wetter than today. Both the mineralogical composition of the sediment (ranging from quartz, mica, gypsum, phosphates, and calcite to garnet, zircon, titanite, olivine, serpentine, tourmaline, sphalerite, pyrite/chalcopyrite, and feldspars and the petrological composition of the larger clasts (limestone, sandstone, mudstone, granitoids, serpentinite, amphibolite, diorite, gneiss, quartzite, microconglomerate, and schist ascribe the potential source rocks to an area with contrasting lithologies, such as amphibolites, felsic and basic metaigneous, and metasedimentary rocks, mixed with a variety of detritic rocks. These rock types are not entirely comprised by the catchment area of the modern Presacina Brook, thus implying that due either to hydrological conditions, or to changes in the base level caused by river down cutting or active tectonics, the former source area was much more extensive. Based on morphological and sedimentological criteria, the cave started under pipe-full flow conditions, and further evolved during a prolonged and complex vadose phase. Evidence to support the existence of hypogene conditions is also present. Once the underground stream left the cave and most of the sediment was removed, speleothem precipitation was initiated. In this contribution we put forward evidence that argue for an extra

  13. Fossil remains of the cave animal Marifugia cavatica in the unroofed cave in the Črnotiče quarry, W Slovenia

    Directory of Open Access Journals (Sweden)

    Andrej Mihevc

    2002-12-01

    Full Text Available The paper is a report on the discovery of tubes of a fossilised cave serpulid in a roofless cave in the quarry near village Črnotiče. The site and shape of the fossilised tubes are described. The animals lived attached to the scallops in the wall of the water filled passage. The passage was later filled with clay deposits, followed by a layer of sinter several metres thick. The roof of the passage has been removed by karst denudation and the sinter now reaches to the surface.Fragments of tubes of animals of various sizes have been preserved, attached to the rock wall; those tubes that grew at a right angle to the wall have broken off but been preserved in the sediment. In terms of their dimension and shape the tubes remind one of the tubes of the more recent cave serpulid Marifugia cavatica Absolon and Hrabe. Thedating of the nearby sediments by palaeomagnetic method show that the minimum age of the serpulids is 1.7 Ma, but greater age is more probable.

  14. A juvenile subfossil crocodylian from Anjohibe Cave, Northwestern Madagascar

    Directory of Open Access Journals (Sweden)

    Joshua C. Mathews

    2016-09-01

    Full Text Available Madagascar’s subfossil record preserves a diverse community of animals including elephant birds, pygmy hippopotamus, giant lemurs, turtles, crocodiles, bats, rodents, and carnivorans. These fossil accumulations give us a window into the island’s past from 80,000 years ago to a mere few hundred years ago, recording the extinction of some groups and the persistence of others. The crocodylian subfossil record is limited to two taxa, Voay robustus and Crocodylus niloticus, found at sites distributed throughout the island. V. robustus is extinct while C. niloticus is still found on the island today, but whether these two species overlapped temporally, or if Voay was driven to extinction by competing with Crocodylus remains unknown. While their size and presumed behavior was similar to each other, nearly nothing is known about the growth and development of Voay, as the overwhelming majority of fossil specimens represent mature adult individuals. Here we describe a nearly complete juvenile crocodylian specimen from Anjohibe Cave, northwestern Madagascar. The specimen is referred to Crocodylus based on the presence of caviconchal recesses on the medial wall of the maxillae, and to C. niloticus based on the presence of an oval shaped internal choana, lack of rostral ornamentation and a long narrow snout. However, as there are currently no described juvenile specimens of Voay robustus, it is important to recognize that some of the defining characteristics of that genus may have changed through ontogeny. Elements include a nearly complete skull and many postcranial elements (cervical, thoracic, sacral, and caudal vertebrae, pectoral elements, pelvic elements, forelimb and hindlimb elements, osteoderms. Crocodylus niloticus currently inhabits Madagascar but is locally extinct from this particular region; radiometric dating indicates an age of ∼460–310 years before present (BP. This specimen clearly represents a juvenile based on the extremely small

  15. Eastern slopes grizzly bear project

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2001-01-01

    The cumulative effects of human activities on the grizzly bears in the central Canadian Rockies are not well known. As a result, a project was initiated in 1994 to address the urgent requirement for accurate scientific information on the habitat and populations of grizzly bears in the area of the Banff National Park and Kananaskis Country. This area is probably the most heavily used and developed area where the grizzly still survives. The information gathered throughout the course of this study will be used to better protect and manage the bears and other sensitive carnivores in the region. Using telemetry, researchers are monitoring 25 grizzly bears which were radio-collared in a 22,000 square-kilometer area in the upper Bow Valley drainage of the eastern Alberta slopes. The researchers involved in the project are working with representatives from Husky Oil and Talisman Energy on the sound development of the Moose Mountain oil and gas field without adversely affecting the grizzly bear population. Information collected over seven years indicated that the grizzly bears have few and infrequent offspring. Using the information gathered so far, the location of the Moose Mountain to Jumping Pound pipeline was carefully selected, since the bears recover very slowly from high mortality, and also considering that the food and cover had already been compromised by the high number of roads, trails and other human activities in the area. The status of the population and habitat of the grizzly bear will be assessed upon the conclusion of the field research phase in 2001. Models will be updated using the data obtained during eight years and will assist in the understanding of complex variables that affect grizzly bears.

  16. EFFECT OF BEARING MACROGEOMETRY ON BEARING PERFORMANCE IN ELASTOHYDRODYNAMIC LUBRICATION

    Directory of Open Access Journals (Sweden)

    Emin GÜLLÜ

    2000-01-01

    Full Text Available During manufacturing, ideal dimension and mutual positioning of machine elements proposed in project desing can be achieved only within certain range of tolerances. These tolerances, being classified in two groups, related to micro and macro geometry of machine elements, don't have to effect the functioning of these elements. So, as for all machine elements, investigation of the effects of macro and micro tolerances for journal bearings is important. In this study, we have investigated the effect of macro geometric irregularities of journal bearings on performance characteristics. In this regard, we have studied the change of bearing performance in respect to deviation from ideal circle for an elliptic shaft with small ovality rolling in circular journal bearing.

  17. The Impact of Geomorphology and Human Disturbances on the Faunal Distributions in Tiquara and Angico Caves of Campo Formoso, Bahia, Brazil

    Directory of Open Access Journals (Sweden)

    André Vieira de Araujo

    2015-04-01

    Full Text Available Characterization of fauna is important for the understanding of communities and ecosystems, enabling the design of actions for conservation. In the present piece of work, we identified total 45 morphospecies belonging to the order Acarina, Pseudoscorpionida, Dictyoptera, Araneida, Amblypygi, Isopoda, Plecoptera, Amphipoda, Zygentoma, Spirostreptida, Coleoptera, Collembola, Diptera, Ensifera, Heteroptera, Hymenoptera, Lepidoptera and Psocoptera from two distinct types of caves of Campo Formoso, state of Bahia in Brazil. It was made to provide subsidies for conservation studies. The targeted caves were Tiquara Cave suffered for many years from saltpeter extraction and Angico Cave less visited cave having high tourist potential. Though the conservation status is much better in Angico cave, but we found comparatively more morphospecies in Tiquara cave.

  18. Questioning current practice in brown bear, Ursus arctos, conservation in Europe that undervalues taxonomy

    Energy Technology Data Exchange (ETDEWEB)

    Gippoliti, S.

    2016-07-01

    The present paper highlights problems associated with the currently–accepted taxonomy of brown bear, Ursus arctos, and their consequences for conservation at the European level. The enormous morphological variability within Ursus arctos is not acknowledged in current taxonomy and conservation practice. Seven major clades are recognized in Ursus arctos by molecular researchers, and although Western Europe maintains most of the populations belonging to the relict Clade 1 brown bear lineage, no reference to this is made in current conservation policy. Furthermore, the tiny population of Apennine brown bears, characterized by unique skull morphology, is not even recognized as a distinct ESU (evolutionari significant unit) by current European legislation, nor is it included in the IUCN Red List. This may have serious consequences as brown bear conservation in Western Europe has been mainly based on restocking and reintroduction programs. (Author)

  19. Non-contacting "snubber bearing" for passive magnetic bearing systems

    Science.gov (United States)

    Post, Richard F

    2017-08-22

    A new non-contacting magnetic "snubber" bearing is provided for application to rotating systems such as vehicular electromechanical battery systems subject to frequent accelerations. The design is such that in the equilibrium position the drag force of the snubber is very small (milliwatts). However in a typical case, if the rotor is displaced by as little as 2 millimeters a large restoring force is generated without any physical contact between the stationary and rotating parts of the snubber bearing.

  20. Bears, Big and Little. Young Discovery Library Series.

    Science.gov (United States)

    Pfeffer, Pierre

    This book is written for children 5 through 10. Part of a series designed to develop their curiosity, fascinate them and educate them, this volume describes: (1) the eight species of bears, including black bear, brown bear, grizzly bear, spectacled bear, sun bear, sloth bear, polar bear, and giant panda; (2) geographical habitats of bears; (3)…

  1. Identification of ancient textile fibres from Khirbet Qumran caves using synchrotron radiation microbeam diffraction

    Energy Technology Data Exchange (ETDEWEB)

    Mueller, Martin [Institut fuer Experimentelle und Angewandte Physik der Christian, Albrechts, Universitaet zu Kiel, Leibnizstr. 19, D-24098 Kiel (Germany)]. E-mail: mmueller@physik.uni-kiel.de; Murphy, Bridget [Institut fuer Experimentelle und Angewandte Physik der Christian, Albrechts, Universitaet zu Kiel, Leibnizstr. 19, D-24098 Kiel (Germany); Burghammer, Manfred [European Synchrotron Radiation Facility, B.P. 220, F-38043 Grenoble Cedex (France); Riekel, Christian [European Synchrotron Radiation Facility, B.P. 220, F-38043 Grenoble Cedex (France); Roberts, Mark [Daresbury Laboratory, Keckwick Lane, Warrington WA4 4AD (United Kingdom); Papiz, Miroslav [Daresbury Laboratory, Keckwick Lane, Warrington WA4 4AD (United Kingdom); Clarke, David [Daresbury Laboratory, Keckwick Lane, Warrington WA4 4AD (United Kingdom); Gunneweg, Jan [Institute of Archaeology, The Hebrew University of Jerusalem, Mount Scopus, Jerusalem (Israel); Pantos, Emmanuel [Daresbury Laboratory, Keckwick Lane, Warrington WA4 4AD (United Kingdom)

    2004-10-08

    Archaeological textiles fragments from the caves of Qumran in the Dead Sea region were investigated by means of X-ray microbeam diffraction on single fibres. This non-destructive technique made the identification of the used plant textile fibres possible. Apart from bast fibres (mainly flax), cotton was identified which was most unexpected in the archaeological context.

  2. Dynamics of complex microbiota and enzymes in Divle Cave cheese and their biochemical consequences

    NARCIS (Netherlands)

    Ozturkoglu Budak, S.

    2016-01-01

    Divle Cave cheese is a raw ewe’s milk cheese ripened with the aid of a rich microbiota and a wide range of protease and lipase enzymes secreted by individual strains belong to this microbial community. The study presented in this thesis mainly aims to define the diversity and evolution of the

  3. Avifaunal changes revealed in Quaternary deposits near Waitomo Caves, North Island, New Zealand

    International Nuclear Information System (INIS)

    Worthy, T.H.; Swabey, E.J.

    2002-01-01

    Late Pleistocene (23,000-10,000 14 C yr BP) and Holocene (10,000 14 C yr - present BP) avifaunas are described from the Henry Lambert and associated passages in Gardners Gut Cave, Waitomo Caves, North Island, New Zealand. Nine radiocarbon dates on bones and three uranium series dates on speleothems support the dating of the sites. These data are augmented by six new dates and reanalysis of the avifaunas from F1c Cave, also in the Waitomo karst. A distinctive Pleistocene avifauna characterised by the moa Euryapterix curtus and Pachyornis mappini and the North Island goose (Cnemiornis gracilis) with common associates including New Zealand coot (Fulica prisca), North Island takahe (Porphyrio mantelli), Finsch's duck (Euryanas finschi), and North Island kokako (Callaeas wilsoni) was present. The presence of kokako, saddleback (Philesturnus rufusater), and robin (Petroica longipes) in the Pleistocene deposits and the absence of grassland taxa such as pipit (Anthus noveaseelandiae) and quail (Coturnix novaezelandiae) indicate that the vegetation about Gardners Gut Cave included tall shrubland and probably lacked much grassland, even over the Last Glacial Maximum. The Holocene at Waitomo was characterised by a moa fauna dominated by Anomalopteryx didiformis, although both Euryapteryx curtus and Pachyornis mappini persisted in small numbers. The frequent occurrence of kakapo (Strigops habroptilus), weka (Gallirallus australis), and brown teal (Anas chlorotis) typifies Holocene avifaunas; Cnemiornis and Fulica are unknown from Holocene deposits in the area. (author). 45 refs., 7 figs., 8 tabs

  4. Integrated geophysical surveys to assess the structural conditions of a karstic cave of archaeological importance

    Directory of Open Access Journals (Sweden)

    G. Leucci

    2005-01-01

    Full Text Available An integrated geophysical survey using both the electrical resistivity tomography (ERT and ground-penetrating radar (GPR methods was undertaken over a cave of great archaeological interest in southern Italy. The survey was performed to assess the stability of the carbonate rock roof of the cave. A geophysical survey was preferred to boreholes and geotechnical tests, in order to avoid the risk of mass movements. The interpretation of integrated data from ERT and GPR resulted in an evaluation of some of the electromagnetic (EM characteristics (such as the EM wave velocity and the detection of discontinuities (fractures in the carbonate rock. It is well known that rock fractures constitute a serious problem in cave maintenance, and progressive cracking within the bed rock is considered to be one of the main causes of collapse. An analysis of the back-scattered energy was also required for the GPR data interpretation. Cracks within the bedrock were detected to a depth of about 2 m by using GPR, which allowed for the identification of the loosened zone around the cave.

  5. 77 FR 59221 - Information Collection Activities: Timpanogos Cave National Monument Visitor and Community Survey

    Science.gov (United States)

    2012-09-26

    ... of how each of the above management issue affects their overall quality of visit experience. Visitors... collect visitors and local community members' perceptions and evaluations of four management issues (1... management issues: (1) Cave tour size and frequency. (2) Ticketing process and fees. (3) Concession service...

  6. Antibacterial Secondary Metabolites from the Cave Sponge Xestospongia sp.

    Directory of Open Access Journals (Sweden)

    Sridevi Ankisetty

    2012-05-01

    Full Text Available Chemical investigation of the cave sponge Xestospongia sp. resulted in the isolation of three new polyacetylenic long chain compounds along with two known metabolites. The structures of the new metabolites were established by NMR and MS analyses. The antibacterial activity of the new metabolites was also evaluated.

  7. Monitoring of microbial indicator groups in caves through the use of RIDA ® COUNT kits

    Czech Academy of Sciences Publication Activity Database

    Mulec, J.; Krištůfek, Václav; Chroňáková, Alica

    2012-01-01

    Roč. 41, 2/3 (2012), s. 287-296 ISSN 0583-6050 R&D Projects: GA MŠk LC06066 Grant - others:SSJ(SK) ITMS 24150120041-OPZP-P05-09-01 Institutional support: RVO:60077344 Keywords : caves * microorganisms * monitoring * human impact * water quality Subject RIV: EE - Microbiology, Virology Impact factor: 0.542, year: 2012

  8. Wintering bats of the upper Snake River Plain: occurrence in lava-tube caves

    Energy Technology Data Exchange (ETDEWEB)

    Genter, D.L.

    1986-04-30

    Distribution and habitat selection of hibernating bats at the Idaho National Engineering Laboratory (INEL) and adjacent area are reported. Exploration of over 30 lava-tube caves revealed that two species, Myotis leibii and Plecotus townsendii, hibernate in the upper Snake River Plain. Five species, M. lucifugus, M. evotis, Eptesicus fuscus, Lasionycteris noctivagans, and Lasiurus cinereus are considered migratory. Myotis leibii and P. townsendii hibernate throughout much of the area, occasionally in mixed-species groups. Myotis leibii uses the dark and protected regions of the cave, usually wedged into tiny pockets and crevices near or at the highest portion of the ceiling. Individuals of P. townsendii may be found at any height or depth in the cave. Temperature appears to be primary limiting factor in habitat selection. Myotis leibii was found in significantly cooler air temperatures than P. townsendii. Neither species tolerated continuous temperatures below 1.5 C. Relative humidity does not seem to be a significant factor in the distribution or habitat selection of the two species in lava-tube caves. 18 references, 1 figure, 1 table.

  9. Adits, Caves, Karizi-Qanats, and Tunnels in Afghanistan: An Annotated Bibliography

    Science.gov (United States)

    2005-11-30

    explained to the district governors of relevant districts.” Iniguex, Lorena and Thomas S. Lauder . October 10, 2001. “Caves in Afghanistan.” Los...Delivery is scheduled in 2008, Dyer said, and there’s been some integration investment and "shifting of money to the left to make sure we get the

  10. SECOND RADIOCARBON INTERCOMPARISON PROGRAM FOR THE CHAUVET-PONT D'ARC CAVE, ARDECHE, FRANCE

    NARCIS (Netherlands)

    Quiles, A.; Valladas, H.; Geneste, J-M; Clottes, J.; Baffier, D.; Berthier, B.; Brock, F.; Ramsey, C. Bronk; Delque-Kolic, E.; Dumoulin, J-P; Hajdas, I.; Hippe, K.; Hodgins, G. W. L.; Hogg, A.; Jull, A. J. T.; Kaltnecker, E.; de Martino, M.; Oberlin, C.; Petchey, F.; Steier, P.; Synal, H-A; van der Plicht, J.; Wild, E. M.; Zazzo, A.

    2014-01-01

    The Chauvet-Pont d'Arc Cave is one of the most important sites for the study of the earliest manifestations and development of prehistoric art at the beginning of the Upper Paleolithic. Different dating techniques have been performed thus far (AMS C-14, U/Th TIMS, Cl-36 dating) to model the

  11. Influence of Mining Pollution on Metal Bioaccumulation and Biomarker Responses in Cave Dwelling Fish, Clarias gariepinus.

    Science.gov (United States)

    du Preez, Gerhard; Wepener, Victor

    2016-07-01

    Cave ecosystems remain largely unstudied and risk being severely degraded as a result of anthropogenic activities. The Wonderfontein Cave, situated in the extensive gold mining region of the Witwatersrand Basin, is one such system that hosts a population of Clarias gariepinus, which is exposed to the influx of polluted mine water from the Wonderfontein Spruit River. The aim of this study was to investigate the bioaccumulation of metals, as well as relevant biomarkers, in C. gariepinus specimens sampled from the Wonderfontein Cave during high (April 2013) and low (September 2013) flow surveys. Results were also compared to a surface population associated with the Wonderfontein Spruit River. There were temporal differences in metal bioaccumulation patterns and this was attributed to the lack of dilution during the low flow period. Metals associated with acid mine drainage, i.e. Co, Mn and Zn were significantly higher in the Wonderfontein Cave population and were reflected in an increase in oxidative stress biomarkers (catalase, protein carbonyls and superoxide dismutase) and the induction of metallothionein, a biomarker of metal exposure. The surface population was exposed to metals associated with geological weathering processes, i.e. Fe and Al.

  12. Diverse archaeal community of a bat guano pile in Domica Cave (Slovak Karst, Slovakia)

    Czech Academy of Sciences Publication Activity Database

    Chroňáková, Alica; Horák, Aleš; Elhottová, Dana; Krištůfek, Václav

    2009-01-01

    Roč. 54, č. 5 (2009), s. 436-446 ISSN 0015-5632 R&D Projects: GA MŠk LC06066 Institutional research plan: CEZ:AV0Z60660521; CEZ:AV0Z60220518 Keywords : archaeal community * bat guano pile * Domica Cave Subject RIV: EH - Ecology, Behaviour Impact factor: 0.978, year: 2009

  13. Diversity and biocide susceptibility of fungal assemblages dwelling in the Art Gallery of Magura Cave, Bulgaria

    Czech Academy of Sciences Publication Activity Database

    Mitova, M.M.; Iliev, M.; Nováková, Alena; Gorbushina, A.A.; Groudeva, V.I.; Martin-Sanchez, P.M.

    2017-01-01

    Roč. 46, č. 1 (2017), s. 67-80 ISSN 0392-6672 Institutional support: RVO:61388971 Keywords : fungi * cultivable microorganisms * rock-art caves Subject RIV: EE - Microbiology, Virology OBOR OECD: Microbiology Impact factor: 1.439, year: 2016

  14. Direct radiocarbon dates for prehistoric paintings at the Altamira, El Castillo and Niaux caves

    International Nuclear Information System (INIS)

    Valladas, H.; Cachier, H.; Maurice, P.; Arnold, M.; Quiros, F.B. de; Valdes, V.C.; Uzquiano, P.

    1992-01-01

    Among things that most strikingly distinguish modern humans from other hominids and the rest of the animal kingdom is the ability to represent things and events pictorially. Complex paintings of the type discovered in the Altamira, El Castillo, Niaux and Lascaux caves represent an important stepping stone in the cultural evolution of humankind. Until now dates were derived from style or dated remains left by prehistoric visitors and could be biased by prolonged occupation or visits unrelated to painting activity. Here we report the first radiocarbon dates for the charcoal used to draw stylistically similar bisons in these caves: 14,000 ± 400 yr BP in the Spanish caves of Altamira, 12,990 ± 200 yr BP in El Castillo, and 12,890 ± 160 yr BP for a bison of different style in the French Pyrenean cave of Niaux. Our results demonstrate the imprecise nature of stylistic dating and show that painting dates derived from remains of human activities should be used with caution. (Author)

  15. Spatially dense drip hydrological monitoring and infiltration behaviour at the Wellington Caves, South East Australia

    Directory of Open Access Journals (Sweden)

    Jex Catherine N.

    2012-07-01

    Full Text Available Despite the fact that karst regions are recognised as significant groundwater resources, the nature of groundwater flow paths in the unsaturated zone of such fractured rock is at present poorly understood. Many traditional methods for constraining groundwater flow regimes in karst aquifers are focussed on the faster drainage components and are unable to inform on the smaller fracture or matrix-flow components of the system. Caves however, offer a natural inception point to observe both the long term storage and the preferential movement of water through the unsaturated zone of such fractured carbonate rock by monitoring of drip rates of stalactites, soda straws and seepage from fractures/micro fissures that emerge in the cave ceiling. Here we present the largest spatial survey of automated cave drip rate monitoring published to date with the aim of better understanding both karst drip water hydrogeology and the relationship between drip hydrology and surface climate. By the application of cross correlation functions and multi-dimensional scaling, clustered by k-means technique, we demonstrate the nature of the relationships between drip behaviour and initial surface infiltration and similarity amongst the drip rate time series themselves that may be interpreted in terms of flow regimes and cave chamber morphology and lithology.

  16. The diversity and evolution of microbiota in traditional Turkish Divle Cave cheese during ripening

    NARCIS (Netherlands)

    Budak, S. O.; Figge, M. J.; Houbraken, J.; de Vries, R. P.

    2016-01-01

    The microbial diversity of traditional Turkish Divle Cave cheese was evaluated in three independent batches. Using molecular techniques, twenty three bacterial species were identified in the interior and outer part of the cheese on days 60 and 120. Bacilli and Gammaproteobacteria classes were

  17. Notes on LCW Activation Calculation for Neutron Imaging Operations in the North Cave of Building 194

    Energy Technology Data Exchange (ETDEWEB)

    Anderson, S. G. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

    2017-09-20

    This note estimates the amount of activation that could be produced in the Facilities-provided Low Conductivity Water (LCW) that is proposed to be used for cooling of electromagnets and beam stops in the Neutron Imaging (NI) accelerator project in the North Cave of Building 194.

  18. Age constraints for Palaeolithic cave art by U-Th dating of thin carbonate crusts

    Science.gov (United States)

    Hoffmann, Dirk; Pike, Alistair; Garcia-Diez, Marcos; Pettitt, Paul; Zilhão, João

    2015-04-01

    U-series dating is an important geochronological tool which is widely applied for instance in speleothem based palaeoclimate research. It has also great potential to provide age constraints for Archaeology, especially for sites or artefacts in cave environments. We present our methods to conduct precise U-Th dating of calcite crusts that formed on top of cave paintings. Recent developments in multi-collector (MC) inductively coupled plasma mass spectrometry (ICPMS) U-series dating greatly improved the precision of this method, and sample sizes needed to obtain reliable results were significantly reduced. Based on these developments the U-series technique can be applied for accurate dating of thin calcite crusts covering cave art at many sites, while taking care not to harm the art underneath. The method provides minimum ages for the covered art and, where possible, also maximum ages by dating the flowstone layer the art is painted on. The U-Th method has been used in a number of recent projects to date calcite precipitates above and occasionally below cave paintings in Spain. Initial results from Cantabria have shown that the earliest dated paintings are older than 41.4 ± 0.6 ka, dating at least to the Early Aurignacian period and present a far longer chronology than that based so far on radiocarbon dating. Here we outline our methodology and the steps we take to demonstrate the reliability of U-Th dates, and present some recent results of our ongoing U-Th dating programme.

  19. Speleothems from Mawsmai and Krem Phyllut caves, Meghalaya, India: some evidences on biogenic activities

    Science.gov (United States)

    Baskar, Sushmitha; Baskar, R.; Lee, Natuschka; Theophilus, P. K.

    2009-05-01

    The Mawsmai cave and Krem Phyllut caves, East Khasi hills, Meghalaya, India has so far not yet attracted the attention of geomicrobiologists. Observations and hypotheses on the possible influence of identified microorganisms for speleothem formations in Meghalaya are reported for the first time. XRD studies identified calcite in speleothems and gypsum in cave wall deposits as the dominant minerals. SEM-EDAX showed interesting microfabric features showing strong resemblance with fossilised bacteria, calcified filaments, needle calcite and numerous nano scale calcite crystals, highly weathered and disintegrated crystals of calcite, that point towards a significant microbial influence in its genesis. Thin section petrography showed laminated stromatolitic features. The microorganisms identified by conventional isolation and further evaluation of isolates by molecular techniques include Bacillus cereus, Bacillus mycoides, Bacillus licheniformis, Micrococcus luteus, and Actinomycetes. Microscopic observations also showed unidentifiable cocci and four unidentifiable strains of CaSO4 (gypsum) precipitating bacteria. Experimental studies confirmed that these bacteria are able to precipitate calcium minerals (calcite, gypsum, minor amounts of dolomite) in the laboratory. These results allow us to postulate that species like these may contribute to active biogenic influence in the cave formations at Meghalaya.

  20. Palygorskite from cave sediments: case study from Wadi Haqil, United Arab Emirates

    Czech Academy of Sciences Publication Activity Database

    Zupan Hajna, N.; Skála, Roman; Al-Farraj, A.; Šťastný, Martin; Bosák, Pavel

    2016-01-01

    Roč. 9, č. 17 (2016), č. článku 689. ISSN 1866-7511 Institutional support: RVO:67985831 Keywords : palygorskite * gypsum * cave sediments * X-ray powder diffraction * scanning electron microscopy * Ras Al-Khaimah Emirate Subject RIV: DB - Geology ; Mineralogy Impact factor: 0.955, year: 2016