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PubMedDate not supplied

CAVE and fishtank virtual-reality displays: a qualitative and quantitative comparison.

We present the results from a qualitative and quantitative user study comparing fishtank virtual-reality (VR) and CAVE displays. The results of the qualitative study show that users preferred the fishtank VR display to the CAVE system for our scientific visualization application because of perceived higher resolution, brightness and crispness of imagery, and comfort of use. The results of the quantitative study show that users performed an abstract visual search task significantly more quickly and more accurately on the fishtank VR display system than in the CAVE. The same study also showed that visual context had no significant effect on task performance for either of the platforms. We suggest that fishtank VR displays are more effective than CAVEs for applications in which the task occurs outside the user's reference frame, the user views and manipulates the virtual world from the outside in, and the size of the virtual object that the user interacts with is smaller than the user's body and fits into the fishtank VR display. The results of both studies support this proposition.

Data Display↗
PubMed2001

Molecular biogeography of cave life: a study using mitochondrial DNA from bathysciine beetles.

This study focuses on phylogenetic relationships in two distinct species assemblages of cave-dwelling beetles with similar disjunct distributions in the Pyrenees and Sardinia. One assemblage contains six species in the genera Ovobathysciola (four species) and Patriziella (two species) on Sardinia and one species of Anillochlamys in the Pyrenees. Species within the two Sardinian genera co-occur in the same karst area. Although, they are believed to be each others closest relative, they have very different body types (globular body with short appendages in Ovobathysciola; elongated body with long appendages in Patriziella), which are believed to reflect different degrees of adaptation to cave life. The other assemblage of Bathysciine beetles includes three species in the genus Speonomus in the Pyrenees and one on Sardinia. All the species are rare and many are endangered. One issue of particular interest was whether Ovobathysciola and Patriziella are reciprocally monophyletic or whether each of the Patriziella species evolved independently from the co-occurring Ovobathysciola species, as the similar morphology of the Patriziella species might be due to convergence rather than common descent. Based on DNA sequences of the cytochrome oxidase I (COI) region of the mtDNA, neither scenario was supported. Rather, the two Patriziella species are sister taxa embedded within the Ovobathysciola radiation. In addition, the well-dated geological history of this region allowed us to calibrate absolute rates of COI evolution, the first such estimates for any insect. Finally this study suggests that the evolutionary acquisition of typical cave adaptations (e.g., elongated body and appendages) may occur at about the same rate as loss of traits (e.g., eyes and pigmentation) associated with cave life.

Animals↗
PubMed2006

Brooding crustaceans in a highly fragmented habitat: the genetic structure of Mediterranean marine cave-dwelling mysid populations.

Habitat fragmentation and climate change are two major threats on biodiversity. Fragmentation limits the number of patches and their decreased connectivity cannot always maintain populations at dynamic equilibrium. The natural extreme fragmentation of marine cave habitats represents an opportunity to understand how these processes interact. The hypothesis of a low gene flow among populations due to a high level of fragmentation was tested by analysing sequence variation in a fragment of the mitochondrial gene of the cytochrome oxidase subunit I in 170 individuals (23 localities across the NW Mediterranean) of two marine cave-dwelling mysids of the genus Hemimysis. The species Hemimysis margalefi recently replaced its congener Hemimysis speluncola, a species shift that could be related to the warming of the Mediterranean Sea and to differences in their thermal tolerances. There were too few H. speluncola samples to further discuss their genetic structuring, but for H. margalefi, the present study revealed high levels of genetic diversity and genetic structuring, as shown by the eight genetically distinct groups identified. The Croatian group might constitute a sibling species due to a strong divergence (15%). Nevertheless, these groups present reduced but orientated gene flow according to the general circulation in the Mediterranean, and fit a stepping-stone model. At local scale (Marseille area, France), gene flow among caves is dependent on unexpected local hydrodynamic barriers, that determine metapopulation sizes. Through the example of mysid species inhabiting marine caves, the present work confirms the strong influence of habitat disjunction (natural fragmentation) on population structure, and stresses the importance of coastal geomorphological features in inducing complex interactions between the circulation of water masses and the circulation of genes.

Animals↗
PubMedDate not supplied

Chemical erosion of the Lilburn Cave system, Kings Canyon National Park, California.

Multi-year instrumental records for input, throughflow and output waters of the Lilburn Cave system provide control on denudation rates as they respond to seasonal and spatial variability. Data suggest that maximum denudation is in the late fall and early winter. This is when non-snowmelt discharge is at its maximum. At lower discharge rates the volume of water moving through the cave system is the limiting control on the volume of denudation. During periods of snowmelt the limiting control is the rate at which the calcite dissolves. This is probably the result of water flowing through wider channels during these times. Based on instrumental measurements, there is considerable variation in terms of where denudation occurs inside the cave. The loci of dissolution change from year to year. This is to be expected in the dynamic environment of the cave where materials shift routinely. This variability should be studied over longer periods of time in order to more fully understand its extent. The relatively small area of carbonate exposure relative to the area of the drainage basin gives rise to relatively high denudation rates. The carbonate is being removed at a rate of about 5000 metric tons per year, or at about 830 mm/y. This is about five times the rate reported in the humid karst regions of Malaysia. This information indicates that the relative proportion of carbonate in the drainage basin needs to be considered when trying to estimate denudation in other areas.

Calcium Carbonate↗
PubMed2005

Genomic sequencing of Pleistocene cave bears.

Despite the greater information content of genomic DNA, ancient DNA studies have largely been limited to the amplification of mitochondrial sequences. Here we describe metagenomic libraries constructed with unamplified DNA extracted from skeletal remains of two 40,000-year-old extinct cave bears. Analysis of approximately 1 megabase of sequence from each library showed that despite significant microbial contamination, 5.8 and 1.1% of clones contained cave bear inserts, yielding 26,861 base pairs of cave bear genome sequence. Comparison of cave bear and modern bear sequences revealed the evolutionary relationship of these lineages. The metagenomic approach used here establishes the feasibility of ancient DNA genome sequencing programs.

Animals↗
PubMed1985

Maintenance therapy: a two year comparison between Caved-S and cimetidine treatment in the prevention of symptomatic gastric ulcer recurrence.

Eighty two patients with an endoscopically healed gastric ulcer, were treated for two years with either Caved-S tablets, two twice daily or cimetidine 400 mg at night. During the first year, 12% (four out of 34) of the Caved-S group and 10% (four out of 41) of the cimetidine group had an ulcer recurrence. By the end of the second year, the recurrence rate was 29% (nine out of 31) in the Caved-S group, and 25% (eight out of 32) for the cimetidine group. Ulcer relapse occurred frequently in patients with either a dyspeptic history of over six months (p less than 0.05), or a past history of a gastric ulcer (p less than 0.001). Ulcers recurred rapidly after maintenance therapy; Caved-S two out of 22; cimetidine seven out of 23, within four months (NS). This study shows that long term maintenance therapy is safe and reasonably effective. The high recurrence rate after stopping treatment suggests that therapy in high risk or elderly patients should be for life.

Adult↗
PubMed2001

[Cave-associated acute pulmonary histoplasmosis in two Japanese returning from Mexico].

We report cases of cave-associated acute pulmonary histoplasmosis that occurred in two Japanese returning from Yucatan, Mexico. Patient 1 is a 35-year-old woman who worked in a bat-infested cave in Mexico for about 3 weeks. Almost all her colleagues had developed cough, fever and headache after 5 days in the cave. She was asymptomatic but her chest radiograph showed multiple nodules 5-10 mm in diameter throughout both lungs. The histoplasmal mycelial-phase complement fixation titer on admission was 1:16, and 1:128 one month later. Patient 2, the 53-year-old husband of patient 1, was also infected by histoplasma in the cave, and similar nodules were observed in his chest radiograph. His histoplasmal complement fixation titer did not elevate. To date, about 20 cases of pulmonary histoplasmosis have been reported in Japan. The number of imported mycoses in Japan is increasing, and histoplasmosis should be considered in the differential diagnosis of pulmonary nodules in travelers returning from endemic areas.

Acute Disease↗
PubMedDate not supplied

The cave that holds clues to life on Mars.

Deep in Lechuguilla Cave, a researcher ponders slots carved millions of years ago by dripping sulfuric acid. Though the cave was formed by acid bubbling up from below, here gases condensed on the chamber's ceiling and then rained down as acid. Scientists think Mars may also hold caves carved by sulfuric acid. On Earth, almost all other caves are formed by flowing water.

Antibiotics, Antineoplastic↗
PubMed2001

Incidence of chromosomal aberrations and micronuclei in cave tour guides.

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.

Cells, Cultured↗
PubMed1989

Prehistoric parasitism in Tennessee: evidence from the analysis of desiccated fecal material collected from Big Bone Cave, Van Buren County, Tennessee.

Eight samples of desiccated human feces collected from Big Bone Cave (40VB103), Van Buren County, Tennessee, were analyzed to determine the presence of ecto- and endoparasitic infection among the prehistoric population using the cave. Radiocarbon-dated torch material from the cave indicated that it was a locus of human activity 2,177 +/- 145 yr ago. Parasitic species identified were: Ascaris lumbricoides, Enterobius vermicularis, fleas of the tribe Phalacropsyllini, and protozoan cysts. The cysts were identified as Giardia using an indirect immunofluorescent antibody test. The only report of Giardia in a prehistoric context is the identification of cysts in 2 1,800-yr-old paleofecal specimens from a cave in Israel. This is the first report of Giardia from paleofeces in the New World.

Animals↗
PubMedDate not supplied

[Karyotypic analysis of human cell lines (CaVe and HeLa) by the method of differential staining of chromosomes].

Karyological analysis of CaVe (human stomach cancer) and HeLa cell lines was carried out by means of differential Giemsa staining. In the CaVe cells 12 marker chromosomes were revealed, seven of them similar to those found in our HeLa cell strain. Four markers in our HeLa subline and seven in CaVe cells were similar to those of HeLa sublines described in literature. The authors have arrived at the conclusion that the CaVe line isolated in 1961 was contaminated and now represents a variant of HeLa cell line.

Cell Line↗
PubMed1984

Histoplasma capsulatum. Isolation from an Australian cave environment and from a patient.

The fungus Histoplasma capsulatum, although commonly found in bat-frequented caves in many countries, has not previously been isolated from that environment in Australia. This report describes the isolation of H. capsulatum from several sources, including cave soil, the organs of mice exposed to the cave environment, and the sputum of a patient clinically diagnosed as having acute pulmonary histoplasmosis after exposure to the cave environment.

Acute Disease↗
PubMed1995

[Studies on the bionomics of Phlebotomus chinensis in mountain cave and its relation to control in northern Sichuan].

After a survey of the gonotrophic cycle of 5147 female Phlebotomus chinensis collected from the caves in the mountain area 1500 m above sea level in Nanping County, Sichuan Province where this sandfly was proved to be the typical predominant wild species living mostly in the wild cave at a very high density, a large cave was sprayed with alphamethrin at a dosage of 50 mg/m2 in July, 1993. As a result, the sandfly density dropped to zero spanning over a period of two peak seasons. The authors consider that the residual effect of alphamethrin as long enough to suppress sandfly density in the cave for at least two years, and stress that the spray is a favourable measure in all the year round in reducing the sandfly population density and preventing visceral leishmaniasis.

Animals↗
PubMed1997

[A case of epidermoid tumor inside the Meckel's cave].

An epidermoid tumor inside the Meckel's cave is rare. The symptoms caused by this tumor include trigeminal neuralgia, facial hypesthesia and paresis of the 3rd, 4th and 6th nerves. A case of epidermoid tumor inside Meckel's cave was presented. A 54-year-old female who had complained of 3rd nerve palsy with right facial hypesthesia since 3 years before was referred to our clinic. Magnetic resonance imaging (MRI) showed the tumor at Meckel's cave. The tumor removal was performed using the orbito-zygomatic approach. To avoid injury of the internal carotid artery and nerves inside the cavernous sinus, removal of the tumor inside the capsule was carried out leaving the capsule. Postoperatively, the tumor removal was confirmed by MRI and improvement of the 3rd and the 5th nerve palsy was obtained three months after surgery. This case suggests that the capsule of the tumor inside the Meckel's cave should be allowed to remain to avoid injury of the adjacent 4th, 5th and 6th nerves and of the internal carotid artery.

Brain Diseases↗
PubMed1978

Treatment of advanced Hodgkin's disease with B-CAVE following MOPP failure.

Between March 1973, and December 1976, 22 patients who developed disease progression during or after MOPP therapy were treated with a new combination, B-CAVe (Bleomycin 5 mg/m2 iv days 1, 28, 35; CCNU 100 mg/m2 po day 1; adriamycin 60 mg/m2 iv day 1; and vinblastine 5 mg/m2 iv day 1). Objective responses were achieved in 17 of 22 patients (77%) and 11 of 22 responses were complete (50%). The actuarial survival for all patients is 16.4 months. For complete responders the median is 24 months with 2 complete responders dead without evidence of Hodgkin's Disease. Median relapse free survival for complete responders has not been reached at 35+ months while that for partial responders is 14 months. Significant adriamycin cardiotoxicity was encountered in two patients. There were no life threatening bacterial infections during B-CAVe. Two patients died of Pneumocystis carinii several months after cessation of therapy. B-CAVe is effective in the therapy of advanced Hodgkin's disease after MOPP failure, and this regimen is comparable to other previously reported MOPP salvage combinations.

Adolescent↗
PubMedDate not supplied

Measurement of the concentration of radon gas in the Toirano's caves (Liguria).

The radioactive gas radon, intermediate term of the decay series of uranium and thorium, is the main contamination source of underground places and may be a risk for high concentration and long exposure time. European and Italian law requires radon concentration to be measured in workplaces and, if the "action level" of 500 Bq/m3 is reached, proper actions must be made in order to decrease the dose commitment. Considering natural showcaves or artificial cavities open to public, the exposition of the visitors is frequently small, due to the short residence time, but accompanying people, remaining underground for long time, may be subject to appreciable dose and the radon concentration should therefore be monitored. The high humidity in natural caves may impair the use of some measuring devices. Therefore, different detection methods were compared (ZnS scintillation counters, E-PERM electret ionisation chambers, cellulose nitrate alpha-track dosimeters) to select the best procedure for long-term investigation. The LR-115 (Kodak) alpha-track dosimeters were insensitive to humidity and permitted to monitor a great number of places at the same time. Measurements have been carried out in the speleological and archaeological site of the Toirano's Caves (Savona, Liguria, Italy) and several points were monitored for two years. Radon concentration strongly depends on the site and changes during the year, due to the difference between internal and external temperature. The maximum dose commitment during the visitors tour, considering the average yearly value of radon concentration, was found to be between 1.5 and 4 microSv. It was found that no risk exists for visitors, but the evaluation of the dose absorbed by the guides and their classification according to the radiation protection law requires a complete monitoring of the average yearly concentration of radon and of the total time spent by each worker into the cave.

Air Pollutants, Radioactive↗
PubMed1990

On the differences between two pelvises of Mousterian context from the Qafzeh and Kebara caves, Israel.

Two pelvises from a similar archaeological context have been discovered in recent years in two different caves in Israel. The pelvis from the Qafzeh cave (Qafzeh 9) was dated by means of thermoluminescence at approximately 95 kyr BP. All available measurement values, the most significant being those of the diagnostic obturator region, fall within those of the modern range. The other pelvis emanates from the Kebara cave and differs fundamentally from modern pelvises and from the Qafzeh specimen, although the Kebara pelvis is 30,000 years younger than the latter. As in other remains of Neandertal pelvises, the superior pubic ramus of the Kebara hominid is extremely long and slender and exhibits a cross section unlike that of modern humans. The absolute height of the obturator region is very small. It is these measurements and proportions that set the Kebara pelvis apart from both modern pelvises and the specimen from Qafzeh. The morphological differences and the chronological relationship between the two fossil pelvises support the concept of two distinct evolutionary lineages for these hominids.

Adult↗
PubMed2004

Somatostatin in the brain of the cave salamander, Hydromantes genei (Amphibia, Plethodontidae): immunohistochemical localization and biochemical characterization.

The distribution of somatostatin-like immunoreactivity in the brain of the cave salamander Hydromantes genei (Amphibia, Plethodontidae) was investigated by using two distinct antisera raised against somatostatin-14. Most somatostatin-positive cells were detected in the ependymal cell layer surrounding the ventricles. These cells possessed the typical morphological characteristics of tanycytes or radial glial cells. Double-labeling with an antiserum against somatostatin and a monoclonal antibody against glial fibrillary acidic protein showed that somatostatin-immunoreactive cells lining the ventricles also exhibited GFAP-like immunoreactivity. Injection of the neurotracer biocytin into the lateral ventricle revealed that neurons lining the ventricles did not contain somatostatin-like immunoreactivity. In the telencephalon, somatostatin-like immunoreactivity was confined to radial glial cells. In the diencephalon, in addition to somatostatin-immunoreactive cells in the ependyma, positive cell bodies were also found in the periventricular preoptic nucleus, the infundibular nucleus, the epiphysis, and the subcommissural organ. In the metencephalon, positive cell bodies were found in the auricula cerebelli, whereas in the rhombencephalon numerous somatostatin-immunoreactive cells were seen lining the ventricular cavity. Immunoreactive nerve fibers were observed in the hypothalamus-median eminence complex. In the pituitary, a discrete group of somatostatin-positive cells was found in the pars distalis. High-performance liquid chromatography analysis of brain extracts revealed that the immunoreactive material coeluted with somatostatin-14. The present results show that the somatostatin peptidergic system in the brain of the cave salamander has a more simple organization than those described in the brain of frog and other vertebrates. This feature is probably related to the expression of high pedomorphic characters in plethodontids. The distribution of somatostatin-like immunoreactivity suggests that, in the cave salamander, somatostatin may act as a neurotransmitter and/or neuromodulator, a central regulator of fluid homeostasis, and a hypophysiotropic neurohormone.

Animals↗