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1.
Sci Total Environ ; 500-501: 34-43, 2014 Dec 01.
Article in English | MEDLINE | ID: mdl-25217742

ABSTRACT

We investigated the ability of summer (Avena sativa [oat], Trifolium incarnatum [crimson clover], Chenopodium [goosefoot]) and winter (Vicia villosa [hairy vetch], Secale Cereale L. [Rye], Brassica napus L. partim [rape]) cover crops, including a mixed species treatment, to extract copper from an organic vineyard soil in situ and the microbial communities that may support it. Clover had the highest copper content (14.3mgCukg(-1) DM). However, it was the amount of total biomass production that determined which species was most effective at overall copper removal per hectare. The winter crop rye produced significantly higher amounts of biomass (3532kgDMha(-1)) and, therefore, removed significantly higher amounts of copper (14,920mgCuha(-1)), despite less accumulation of copper in plant shoots. The maximum annual removal rate, a summation of best performing summer and winter crops, would be 0.033kgCuha(-1)y(-1). Due to this low annual extraction efficiency, which is less than the 6kgCuha(-1)y(-1) permitted for application, phytoextraction cannot be recommended as a general method of copper extraction from vineyards. Copper concentration did not influence aboveground or belowground properties, as indicated by sampling at two distances from the grapevine row with different soil copper concentrations. Soil microorganisms may have become tolerant to the copper levels at this site. Microbial biomass and soil enzyme activities (arylsulfatase and phosphatase) were instead driven by seasonal fluxes of resource pools. Gram+ bacteria were associated with high soil moisture, while fungi seemed to be driven by extractable carbon, which was linked to high plant biomass. There was no microbial group associated with the increased phytoextraction of copper. Moreover, treatment did not influence the abundance, activity or community structure of soil microorganisms.


Subject(s)
Agriculture , Copper/metabolism , Crops, Agricultural/metabolism , Soil Microbiology , Soil Pollutants/metabolism , Biodegradation, Environmental , Copper/analysis , Crops, Agricultural/growth & development , Soil/chemistry , Soil Pollutants/analysis , Vicia/growth & development
2.
Comput Biol Med ; 33(3): 277-92, 2003 May.
Article in English | MEDLINE | ID: mdl-12726806

ABSTRACT

We discuss computationally efficient techniques for confidential storage and transmission of medical image data. Two types of partial encryption techniques based on AES are proposed. The first encrypts a subset of bitplanes of plain image data whereas the second encrypts parts of the JPEG2000 bitstream. We find that encrypting between 20% and 50% of the visual data is sufficient to provide high confidentiality.


Subject(s)
Confidentiality , Image Processing, Computer-Assisted/methods , Information Storage and Retrieval/methods , Humans
3.
Am J Ophthalmol ; 116(4): 489-96, 1993 Oct 15.
Article in English | MEDLINE | ID: mdl-8213981

ABSTRACT

The multiport illumination system was developed as a fiberoptically illuminated pars plana cannula system for vitreous surgery. The retinal irradiance of the multiport illumination system and several other commonly used endoilluminators (light pipes) measured at 5 mm are comparable, ranging from 94 to 256 mW/cm2. In the actual surgical setting, however, the retinal irradiance of the multiport illumination system is far less (56 mW/cm2) because the end of the fiberoptic cables are fixated in the pars plana 16.5 mm away from the retinal surface. A reduction in the maximal intensity (100%) to 50% reduces the retinal irradiance by approximately two thirds to 3.7 mW/cm2. The light emitted by the multiport illumination system used in conjunction with a long-wave pass filter with a cutoff wavelength of 420 nm reduces the amount of short-wavelength light by one third to about 4% of the overall irradiance.


Subject(s)
Lighting/methods , Ophthalmology/instrumentation , Retina/physiology , Vitreous Body/surgery , Eye Diseases/surgery , Fiber Optic Technology/instrumentation , Humans , Lighting/adverse effects , Radiation Injuries , Retina/injuries , Sensory Thresholds , Surgical Equipment
5.
Psychol Rep ; 64(1): 195-201, 1989 Feb.
Article in English | MEDLINE | ID: mdl-2928429

ABSTRACT

The study was designed to assess the stability of WISC-R profiles of 36 learning disabled children given the WISC-R two times. The mean time between tests was 2.5 yr. The pattern reported for learning disabled children on Bannatyne's categories was evident for the group at both times, however, this pattern was not found for the majority of subjects. Analysis indicated a decrease over time in Verbal IQs, Full Scale IQs, and Bannatyne's Conceptual category, confirming previous findings. Possible reasons for the changes in scores are discussed.


Subject(s)
Learning Disabilities/diagnosis , Wechsler Scales , Child , Female , Humans , Learning Disabilities/psychology , Male , Psychometrics
6.
Percept Mot Skills ; 59(2): 415-21, 1984 Oct.
Article in English | MEDLINE | ID: mdl-6514490

ABSTRACT

The WISC-R was administered to 19 learning disabled students at the time of diagnosis and following a period of time in special program placements. Group analyses indicated fluctuations between testing times in the Verbal and Full-Scale IQs and the V-P IQ discrepancies. Small but significant differences in Verbal, Performance and V-P scatter indices were observed at one or both testings in comparison to the normal standardization sample. Although the suggested group pattern for learning disabled children based on the Bannatyne categories was confirmed on both occasions, there was considerable variation for individual subjects.


Subject(s)
Learning Disabilities/diagnosis , Wechsler Scales , Child , Education, Special , Female , Humans , Intelligence , Learning Disabilities/psychology , Male , Psychometrics
7.
Z Geburtshilfe Perinatol ; 183(5): 335-8, 1979 Oct.
Article in German | MEDLINE | ID: mdl-543182

ABSTRACT

Two groups each consisting of twelve healthy students received Fenoterol (0,03 microgram/kg/min) alone or in combination with Verapamil (1,2 micrograms/kg/min) intravenously. In both groups, heart rate, arterial blood pressure amplitude and echocardiographically determined left ventricular contractility parameters increased significantly and equally. These results suggest that Verapamil does not counteract the positive chronotropic and inotropic effect of Fenoterol.


Subject(s)
Ethanolamines/therapeutic use , Fenoterol/therapeutic use , Verapamil/therapeutic use , Adult , Blood Pressure/drug effects , Drug Interactions , Heart Rate/drug effects , Heart Ventricles/drug effects , Humans , Male
8.
Histochem J ; 11(3): 337-44, 1979 May.
Article in English | MEDLINE | ID: mdl-457441

ABSTRACT

The present study is concerned with artifacts likely to occur in a horseradish peroxidase exclusion test. Incubation of murine peritoneal macrophages and lymphocytes with the peroxidase showed a close relationship between the number of living cells and the percentage of cells excluding the tracer. The penetration of the cytoplasm by horseradish peroxidase is attributed to an increase in the permeability of the cell membrane during the incubation (ranging from 10 to 120 min). It was not increased by the presence of tracer throughout the incubation period. However, concomitant fixation of the cell in the presence of horseradish peroxidase caused an increase in the influx of the tracer. The horseradish peroxidase exclusing test applied to the guinea-pig organ of Corti has proved to be valid provided that: (a) mechanical lesions prior to the tracer incubation are avoided; (b) incubation is terminated by removal of the extracellular tracer; (c) fixation is carried out as soon as possible; (d) a low concentration of horseradish peroxidase is used; and (e) specimens are incubated in diaminobenzidine-H2O2 medium for the shortest possible period. Although fixation-induced cytoplasmic infiltration by horseradish peroxidase was not detected in cochlear specimens, the findings call attention to possible sources of error and define the level of significance of the test. Horseradish peroxidase does not appear to be a cytotoxic agent under the conditions used.


Subject(s)
Cell Membrane Permeability , Cochlea/injuries , Horseradish Peroxidase , Organ of Corti/injuries , Peroxidases , Animals , Guinea Pigs , Histocytochemistry , Organ of Corti/ultrastructure
9.
Anat Anz ; 144(4): 383-92, 1978 Sep.
Article in German | MEDLINE | ID: mdl-742724

ABSTRACT

Morphological findings evidenced the impulse noise trauma primarily a mechanical lesion of cells. The loss of mechanically damaged sensory cells results in the initial decline of cochlear microphonics. Due to mechanical lesions many sites of leakage in the wall of the cochlear duct give way to the diffusion of components of either lymph, which will produce a general functional disturbance associated with additional decline of microphonics. The functional restoration of the inner ear requires the previous repair of the endo/perilymphatic barrier.


Subject(s)
Cochlea/pathology , Hearing Loss, Noise-Induced/pathology , Animals , Cochlea/physiopathology , Electrophysiology , Guinea Pigs , Hearing Loss, Noise-Induced/physiopathology , Histocytochemistry , Horseradish Peroxidase
10.
Experientia ; 34(3): 363-4, 1978 Mar 15.
Article in English | MEDLINE | ID: mdl-631267

ABSTRACT

Rapid loss of cochlear microphonics in guinea-pigs previously exposed to high-energy impulse noise was shown to be related to the breakdown of the endolymphatic boundary. The cochlear duct was rendered leaky by deterioration of the reticular membrane, and damage of sensory and supporting cells.


Subject(s)
Cochlea/pathology , Endolymph , Hearing Loss, Noise-Induced/physiopathology , Labyrinthine Fluids , Animals , Cochlear Duct/pathology , Guinea Pigs , Hair Cells, Auditory/pathology , Organ of Corti/pathology
11.
Z Mikrosk Anat Forsch ; 92(4): 731-43, 1978.
Article in German | MEDLINE | ID: mdl-86244

ABSTRACT

Following perilymphatic perfusion and injection into the cisterna cerebello-medullaris, respectively, the distribution pattern of horseradish peroxidase in the cochlea of the guinea pig was studied light and electron microscopically. The findings prove effective tight junctions (zonulae occludentes) between the cells of the epithelial lining of the endolymphatic compartment. At the level of the reticular membrane the tight junctions are far more extended than elsewhere at the cochlear duct epithelium. From the findings a fairly rapid exchange is suggestive between the lymphatic space of the organ of Corti and the tympanic scale. Various types of cells of the cochlear duct actively take up considerable amounts of peroxidase. However, endocytosis of peroxidase by hair cells and particularly by the outer ones is rather scanty. Passive permeation of the tracer through the membran of undamaged hair cells was disproven.


Subject(s)
Cochlea/ultrastructure , Horseradish Peroxidase , Peroxidases , Staining and Labeling/methods , Animals , Cochlear Duct/ultrastructure , Ear, Inner/ultrastructure , Epithelium/ultrastructure , Female , Guinea Pigs , Hair Cells, Auditory/ultrastructure , Intercellular Junctions/ultrastructure , Labyrinthine Fluids/physiology , Male , Organ of Corti/ultrastructure
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