Library

feed icon rss

Your email was sent successfully. Check your inbox.

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

Proceed reservation?

Export
Filter
  • 2005-2009  (1)
  • 1995-1999  (1)
  • 1
    Electronic Resource
    Electronic Resource
    Oxford, UK; Malden, USA : Blackwell Science Inc
    Ground water monitoring & remediation 25 (2005), S. 0 
    ISSN: 1745-6592
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Energy, Environment Protection, Nuclear Power Engineering , Geosciences
    Notes: This study examines the effects of sequential filtration on the particle abundance and lead concentrations in ground water from four monitoring wells in New Jersey with a history of high turbidity, elevated metal concentrations, or where differences in metal concentrations exist between filtered and unfiltered samples. In these monitoring wells, both transportable suspended particles, such as colloidal particles that are suspended in solution, and nontransportable particles that are disturbed during sample collection but not considered mobile transportable species may be present in solution with potential overlap in particle size distribution. Filtration, particularly the operational pore size (25 to 0.45 μm) of the filter, was evaluated as a method to obtain a representative sample of the transportable metal, as defined by the dissolved phase and particles that are persistently suspended in solution. Two monitoring wells at the Denzer-Schaefer site, a silty/clay aquifer with high particle concentrations (〉8900 mg/L) from samples taken with bailers and a low-flow purge (LFP) pump, showed that a filter of pore size 25 μm could remove 60% to 90% of soil-derived particles, with minimal loss of suspended particles from solution. The two monitoring wells within the highly conductive Picatinny Arsenal sand aquifer provided higher particle abundance with the samples collected with bailers (4300 to 6500 mg/L) than with the LFP pump (4 to 11 mg/L), indicating greater artificial particle disruption with a bailer. At Picatinny Arsenal, the major portion of nontransportable particles in the ground water samples could be removed by filtration through a 25–μm pore size filter, with a minimal loss in suspended particles. Filtration of ground water through a 25–μm pore size filter followed by acidification at the sampling site would provide investigators a tool to examine particle transport in aquifers where there exists the potential for artificial particle disruption during sampling.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 2
    Electronic Resource
    Electronic Resource
    Springer
    Cardiovascular drugs and therapy 10 (1997), S. 767-773 
    ISSN: 1573-7241
    Keywords: adenosine ; angioplasty ; ATPase ; catecholamines ; glycolysis ; 5′-nucleotidase ; preconditioning ; protein kinase C
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Preconditioning is an effective means of protecting the heart against prolonged ischemia by pretreating it with a minor insult, and the present paper reviews various controversies in this highly active field of research. In many models, adenosine plays a role by triggering the activation of protein kinase C. It may work in conjunction with other agents, such as bradykinin, but the putative role of noradrenaline is uncertain. Regulation of the enzyme producing adenosine (i.e., 5′-nucleotidase) has been reported during preconditioning but, because its activity does not seem to be associated with infarct size, it is unlikely that the hydrolase plays a pivotal role. Controversial data have been published on the involvement of mitochondrial ATPase, which may be ascribed to the poor time resolution of the experiments described; however, we do not believe that either acidosis or tissue ATP are important factors in triggering preconditioning. The role of glycolysis in the preconditioning effect remains to be firmly established; opposite mechanisms are activated in low-flow and stop-flow protocols. Although species differences regarding preconditioning exist, they seem to be more of a quantitative than a qualitative nature. The phenomenon could be clinically relevant because evidence is accumulating that preconditioning may take place during bypass surgery and coronary angioplasty if longer balloonocclusion times are used.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...