Library

X
feed icon rss

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
  • 1
    Electronic Resource
    Electronic Resource
    Effect of induced fracturing based on a natural fracture system in a dimension stone quarry in the Offerdal Nappe, Sweden (2000)
    Springer
    Bulletin of engineering geology and the environment 58 (2000), S. 215-225 
    Details
    ISSN: 1435-9537
    Keywords: Key words Induced fracturing ; Natural fracture system ; Dimension stone quarry ; Offerdal Nappe ; Mots clés Fracturation induite ; Système de fracturation ; Carrière de roche ornementale ; Nappe de l'Offerdal
    Source: Springer Online Journal Archives 1860-2000
    Topics: Geosciences
    Description / Table of Contents: Résumé L'importance de la fracturation induite par des tirs de mine en carrière a étéétudiée dans la région de Landögssjö, comté de Jämtland (Suède), où la roche ornementale "quartzite Flammet" de la nappe de l'Offerdal est exploitée. Deux cartes des traces de fractures ont été comparées: l'une d'un secteur de la carrière, où les fracturations naturelles et induites sont analysées, l'autre d'un secteur sans carrière où seules les discontinuités naturelles sont présentes. Ces deux types de fracturation, naturelles ou induites, ont donc été distinguées. Le système de fracturation a été décrit en prenant en compte l'orientation, l'extension, l'espacement des fractures et leurs terminaisons. Deux types de terminaisons de fractures induites par le découpage à l'explosif ont été définis: type A: des fractures coalescentes avec au moins une extrémité rejoignant un trou de foration; type B: des fractures coalescentes avec une extrémité rejoignant une fracture de type A. Les fractures de type A augmentent la densité de fracturation initiale jusqu'à 23%. Considérant les fractures de type A et de type B ensemble, une augmentation jusqu'à 36% a été notée. Dans cette analyse, environ 17% des volumes rocheux étudiés présente une augmentation de la fracturation après une opération de découpage à l'explosif.
    Notes: Abstract  The degree of induced fracturing related to bench blasting has been investigated in the Offerdal Nappe in the Landögssjö area, in the county of Jämtland, Sweden where the dimension stone "Flammet Quartzite" is quarried. Two fracture trace maps have been compiled; one from an area within the quarry, where natural and induced fracturing are analysed, and a second from an area where no quarrying has taken place, i.e. where only natural fractures appear. This means that it is possible to take into account differences between natural fractures and induced fractures. The fracture system has been described in the investigated areas according to fracture set orientation, size, frequency and occurrence. Two types of fracture occurrence related to blasting have been defined: (1) coalescing fractures with at least one end terminating in a drill hole (type A), and (2) coalescing fractures with one end terminating in a type A fracture (type B). Fractures of type A increase the fracture frequency by up to 23%. Considering fractures of type A and B together, an increase of up to 36% has been noted. In this investigation, approximately 17% of the rock volume shows increased fracturing from the blasting operation.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/s100640050077
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 2
    Electronic Resource
    Electronic Resource
    Pulmonary complications of umbilical venous catheters (1995)
    Springer
    Pediatric radiology 25 (1995), S. 149-152 
    Details
    ISSN: 1432-1998
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Umbilical venous catheters that are pushed in too far will usually cross the atrial septum and may dislodge in a pulmonary vein. The authors report eight neonates with radiographic documentation of this catheter malposition together with either a localized pulmonary opacification or an autopsy report of a pulmonary hemorrhage or infarction corresponding to the catheter position. The lung injury ranged from a transient edema to hemorrhagic pulmonary infarction and hydrothorax. In two cases autopsy demonstrated localized infarction without previous radiographic signs of catheter-related injury.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF02010332
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 3
    Electronic Resource
    Electronic Resource
    Dopaminergic innervation of striatal grafts placed into different sites of normal striatum: differences in the tyrosine hydroxylase immunoreactive growth pattern (1997)
    Springer
    Experimental brain research 113 (1997), S. 13-23 
    Details
    ISSN: 1432-1106
    Keywords: Transplant ; Striatum ; Substantia nigra ; Patch-matrix ; Regeneration ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract When patients with Parkinson’s disease initially show symptoms, approximately 80–85% of their dopaminergic nerve fibers in the striatum have degenerated. It is thus of importance to develop strategies to try to rescue the remaining dopaminergic neurons and to stimulate them to induce sprouting. In this study the goal was to examine whether the different subgroups of dopaminergic neurons in the ventral mesencephalon projecting to the basal ganglia have different sprouting capacities when stimulated by the trophic effect of a fetal striatal graft. Lateral ganglionic eminence was implanted into the lateral ventricle, the midportion of dorsal striatum, globus pallidus, or ventral striatum. Solid tissue pieces from 13- to 15-mm fetuses were stereotactically implanted into adult female Sprague-Dawley rats. At postgrafting week 4 the animals were perfused and processed for tyrosine hydroxylase (TH) immunohistochemistry. Transplants placed in the lateral ventricle were TH-negative, except for two cases with TH-positive fibers where the ependymal layer was disrupted, thereby allowing direct contact between the graft and the adjacent host striatum. The transplants placed into dorsal striatum were innervated by small patches of dopaminergic nerve fibers. Areas between the TH-positive patchy structures remained TH-negative. In grafts placed into globus pallidus, both patchy structures and a less dense TH-positive nerve fiber network was noted. The TH-positive growth pattern in transplants placed in ventral striatum was also devided into patchy and widespread growth. Grafts placed in globus pallidus and ventral striatum revealed significantly larger areas of TH-positive innervation compared with that measured in grafts placed in dorsal striatum and the lateral ventricle. In conclusion, it is possible to induce sprouting of TH-immunoreactive nerve fibers from all areas examined. The most potent areas to initiate dopaminergic growth were the globus pallidus and ventral striatum, where both a patchy dense and a widespread, less dense growth was induced. Thus, if using a trophic stimulus to induce sprouting from remaining dopaminergic nerve fibers in Parkinson’s disease, the preferential target to induce sprouting would be ventromedial striatum and growth would be guided toward dorsal striatum owing to the enhanced dopaminergic growth properties in the ventromedial areas.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF02454138
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 4
    Electronic Resource
    Electronic Resource
    Prediction of a fracture system from an excavated ditch in the central Caledonides, Sweden (2000)
    Springer
    Bulletin of engineering geology and the environment 58 (2000), S. 159-165 
    Details
    ISSN: 1435-9537
    Keywords: Key words Fracture ; Dimension stone Quarry ; Prediction ; Caledonides ; Sweden
    Source: Springer Online Journal Archives 1860-2000
    Topics: Geosciences
    Description / Table of Contents: Résumé La prospection de roches dimensionnelles dans la région de Finnsäter (nappe d'Offerdal, Calédonides de Suède) est réalisée dans une région où le substratum n'affleure pas et ne permet donc pas d'évaluer la qualité probable de la roche et le taux de récupération effectif. Il est donc nécessaire de connaître le système local de fracturation. L'article présente une étude de cas réalisée dans la région de Finnsäter où une cartographie à partir de tranchées a été réalisée pour prévoir le système de fracturation. Une comparaison a été faite entre une carte de fracturation extrapolée à partir des données d'une cartographie de tranchées et une carte établie à partir d'une grande surface de substratum dégagée, afin d'évaluer si la méthode de cartographie permet de se prononcer sur l'exploitabilité en carrière.
    Notes: Abstract  Prospecting for the dimension stone Offerdalsskiffer in the Finnsäter area, Offerdal Nappe, Swedish Caledonides, is mainly undertaken where no bedrock is exposed in order to assess the likely quality of the rock and the effective recovery ratio. A knowledge of the local fracture system is therefore required. The paper discusses a case study undertaken in the Finnsäter area of Sweden where ditch mapping was carried out to predict the fracture system. A comparsion was made of a fracture map extrapolated from the ditch mapping data and that prepared from a larger cleared bedrock surface in order to assess its potential for quarry viability.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/s100640050010
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...