| 1. |
- Burvall, Anna, et al.
(författare)
-
Communication modes applied to axicons
- 2004
-
Ingår i: Optics Express. - 1094-4087. ; 12:3, s. 377-383
-
Tidskriftsartikel (refereegranskat)abstract
- The communication modes, which constitute a convenient method for the propagation and information analysis of optical fields, are formulated in the generalized axicon geometry. The transmitting region is the axicon’s annular aperture, and the observation domain is the optical axis containing the focal line segment. We show that in rotational symmetry one may employ the prolate spheroidal wave functions to represent the communication modes. Further, in usual circumstances the modes can be approximated by quadratic waves in the aperture domain and by sinc functions in the image domain. Both the exact communication modes and the approximate technique are confirmed numerically, with linear axicons as examples.
|
|
| 2. |
- Burvall, Anna, 1976-, et al.
(författare)
-
Communication modes for information content analysis
- 2004
-
Ingår i: LFNM 2004. - : IEEE conference proceedings. - 0780384296 ; , s. 112-114
-
Konferensbidrag (övrigt vetenskapligt/konstnärligt)abstract
- Approximate modes which give physical understanding for the communication modes theory,are discussed. For the geometry consisting of two line or square apertures, perpendicular to the optical axis, this approximation leads to exactly the same modes as Gabor's theory would yield.
|
|
| 3. |
- Burvall, Anna, et al.
(författare)
-
Communication modes in axicon imaging
- 2004
-
Ingår i: Riao/Optilas 2004: 5th Iberoamerican Meeting On Optics And 8th Latin American Meeting On Optics, Lasers, And Their Applications, Pts 1-3: Ico Regional Meeting. - : SPIE. - 081945575X ; , s. 1133-1137
-
Konferensbidrag (refereegranskat)abstract
- The communication modes are an increasingly frequently used technique for studying the radiation, propagation, and scattering of light. The method is unusual in the way that it gives the information content and the resolution of the fields. It also allows for the possibility of including the noise considerations in the calculations. We present a brief summary of the communication modes method, together with our latest contribution: the communication modes for the axicon geometry.
|
|
| 4. |
- Friberg, Bertil, 1950, et al.
(författare)
-
Long-term follow-up of severely atrophic edentulous mandibles reconstructed with short Brånemark implants.
- 2000
-
Ingår i: Clinical implant dentistry and related research. - 1523-0899. ; 2:4, s. 184-9
-
Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND: Oral implant treatment (Brånemark System) of edentulous mandibles has been presented in numerous studies. However, with regard to the severely atrophic lower jaw, no long-term follow-up studies with solely short implants are available. PURPOSE: The purpose of the present investigation was to retrospectively follow the long-term treatment outcome of patients with severely resorbed edentulous mandibles being subjected to oral implant placement with short (6-7 mm) Brånemark implants. MATERIALS AND METHODS: A total of 247 standard (7 mm long, Ø 3.75 mm) and 13 wide (6 mm long, Ø 5 mm) implants were inserted in 49 patients, all of whom exhibited severe resorption of edentate mandibles. Fixed implant-supported prostheses were manufactured for 45 patients, whereas 4 patients received overdentures. The patients were followed for a mean period of 8 years (range, 1-14 yr). RESULTS: Seventeen implants failed during the study period (cumulative implant survival rate 95.5% at 5-yr and 92.3% at 10-yr follow-up). Implant-supported constructions were worn continuously throughout the investigation by all study subjects. Marginal bone loss, measured after 1, 5, and 10 years of function, concurred with studies of Brånemark implants placed in more voluminous mandibles. No major clinical or construction complications occurred in the followed patients. CONCLUSIONS: The outcome of the present study showed that placement of short Brånemark implants without the use of bone grafting procedures for reconstruction of severely atrophic edentulous mandibles is a highly predictable treatment procedure.
|
|
| 5. |
- Lasaitiene, Daina, 1970, et al.
(författare)
-
Neonatal ACE inhibition in rats interferes with lung development
- 2004
-
Ingår i: Clin Physiol Funct Imaging. - : Wiley. - 1475-0961 .- 1475-097X. ; 24:1, s. 65-8
-
Tidskriftsartikel (refereegranskat)abstract
- The renin-angiotensin system (RAS) is developmentally up-regulated and it is essential for kidney development in several species. Given the fact that the rat lung undergoes postnatal development, the mammalian lung possesses the highest angiotensin-converting enzyme (ACE) levels and ACE activity increases during the first weeks postpartum, we tested the hypothesis that ACE inhibition influences postnatal lung development. Rats were given the ACE inhibitor enalapril (10 mg kg(-1)) from 0 to 9 days of age and their lungs were examined at day 4 and 9. Lung structure was evaluated by means of light microscopy, and surface tension of bronchoalveolar lavage fluid was measured by means of a Wilhelmy balance. Neonatal ACE inhibition lowered the surface tension of bronchoalveolar lavage fluid and caused widening of respiratory airspaces and thinning of alveolar septa. Our results suggest that early postnatal ACE inhibition in rats interferes with lung development.
|
|
| 6. |
- Ljung, Thomas, 1961-, et al.
(författare)
-
Treatment of abdominally obese men with a serotonin reuptake inhibitor: a pilot study.
- 2001
-
Ingår i: Journal of internal medicine. - : Wiley. - 0954-6820 .- 1365-2796. ; 250:3, s. 219-24
-
Tidskriftsartikel (refereegranskat)abstract
- OBJECTIVE: To investigate the effects of a selective serotonin reuptake inhibitor (SSRI) on the neuroendocrine and autonomic nervous system perturbations found in abdominal obesity. DESIGN: Treatment for 6 months with citalopram and for 6 months with placebo using a double-blind, cross-over design, with a 2-month wash-out period between treatment periods. SUBJECTS: Sixteen healthy men, 45-60 years, moderately obese and with an abdominal fat distribution. MEASUREMENTS: Anthropometry, three different depression rating scales, serum lipids, testosterone, IGF-I, oral glucose tolerance test (OGTT), pituitary stimulation with corticotropin releasing hormone (CRH), arithmetic stress test, and excretion of cortisol and metoxycatecholamines in urine, collected during 24 h. RESULTS: Cortisol concentrations in the morning were low before treatment, indicating a perturbed function of the hypothalamic-pituitary-adrenal (HPA) axis. After treatment with citalopram morning cortisol concentrations rose to normal. Cortisol concentrations after stimulation with CRH or stress were elevated by citalopram treatment, but urinary cortisol excretion was unchanged. The glucose concentrations after OGTT (120 min) tended to be reduced, with unchanged insulin concentrations, whilst other metabolic values did not change during treatment. Heart rate after administration of CRH, and during laboratory stress test, decreased by treatment with citalopram. Diurnal urinary excretion of metoxycatecholamines tended to decrease. Neither body mass index nor waist/hip circumference ratio decreased. Depression scores were within normal limits before treatment and did not change. CONCLUSION: The results of this pilot study indicate improvements in the regulation of neuroendocrine-autonomic systems as well as metabolism in abdominal obesity during treatment with an SSRI.
|
|
| 7. |
- Sandman, Per-Olof, et al.
(författare)
-
Kommentarer
- 2004
-
Ingår i: Närståendes behov. - Stockholm : Svensk sjuksköterskeförening. - 9185060097 ; , s. 44-48
-
Bokkapitel (övrigt vetenskapligt/konstnärligt)
|
|
| 8. |
- Thaning, Anna, et al.
(författare)
-
Limits of diffractive optics by communication modes
- 2003
-
Ingår i: Journal of Optics. A, Pure and applied optics. - : IOP Publishing. - 1464-4258 .- 1741-3567. ; 5, s. 153-158
-
Tidskriftsartikel (refereegranskat)abstract
- We apply the concept of communication modes, previously employed in information theory, to diffractive optics. The communication modes are used to study the resolution of one-dimensional optical systems in the Fresnel regime. Using the modes, which in this geometry are prolate spheroidal wavefunctions, the best achievable approximation to a given target field can be assessed. In this paper, the field propagation in terms of the communication modes is demonstrated numerically, and the results on resolution are confirmed by Fourier analysis.
|
|
| 9. |
- Woin, Per, 1958-, et al.
(författare)
-
Effects of the pyrethroid insecticide cypermethrin on a freshwater community studied under field conditions : II. Direct and indirect effects on the species composition
- 2003
-
Ingår i: Aquatic Toxicology. - Amsterdam : Elsevier. - 0166-445X .- 1879-1514. ; 63:4, s. 373-389
-
Tidskriftsartikel (refereegranskat)abstract
- The effects of cypermethrin, a commonly used pyrethroid insecticide, were studied in small in situ enclosures situatedin an eutrophic lake over an 11-day period. The experimental design used a regression principle that included threeuntreated controls and a gradient of six unreplicated cypermethrin concentrations, ranging from 0.01 to 6 mg/l. Thispaper is the second in a series of two and describes the effects on the species composition of the crustacean, rotifer,periphyton and phytoplankton communities. Multivariate ordination technique (redundancy analysis (RDA) combinedwith Monte Carlo permutation tests) showed that exposure to cypermethrin caused significant changes in the speciescomposition of the communities. Changes in the structure of the communities were observed following exposure to anominal concentration of 0.13 mg cypermethrin per litre above. The direct acute effect of exposure to cypermethrin wasa rapid decrease of many species of crustacean zooplankton. The alterations in crustacean species composition wereprobably due to variations in susceptibility to the direct toxic effects of cypermethrin. No effects concentration (NEC)for individual zooplankton species were calculated using inverse regression and revealed that copepod nauplii were themost sensitive (NEC /0.01 mg/l) of the crustacean groups examined. The observed alterations of the speciescomposition of the autotrophic communities as well as of the rotifers were most likely caused indirectly bycypermethrin, mediated through the direct negative effects of the insecticide on the crustacean grazers. The results ofthis experiment provide further knowledge about the direct and indirect effects of pesticide stress on the ecosystem level.They also show that there is a variation in sensitivity between different species of zooplankton under natural conditionsand thus exemplify the necessity of multispecies approaches in the risk assessment of pesticides.
|
|
| 10. |
- Woin, Per, 1958-, et al.
(författare)
-
Effects of the pyrethroid insecticide, cypermethrin, on a freshwater community studied under field conditions : I. Direct and indirect effects on abundance measures of organisms at different trophic levels.
- 2003
-
Ingår i: Aquatic Toxicology. - Amsterdam : Elsevier. - 0166-445X .- 1879-1514. ; 63:4, s. 357-371
-
Tidskriftsartikel (refereegranskat)abstract
- The effects of the pyrethroid insecticide cypermethrin on a natural freshwater community were studied in small in situenclosures over an 11-day period. The experiment was conducted in a eutrophic lake using a regression design thatincluded three untreated controls and a gradient of six unreplicated cypermethrin concentrations, ranging from 0.01 to6.1 mg/l. This paper is the first in a series of two, and describes the fate of cypermethrin and its effects on the abundanceof crustaceans, rotifers, protozoans (cilliates and heterotrophic nanoflagellates (HNF)) and bacteria and the biomass ofperiphytic and planktonic algae. The concentration of cypermethrin decreased quickly during the experiment, with ahalf-life of 48 h for the total and 25 h for the dissolved fractions of cypermethrin, respectively. Cypermethrin proved tobe acutely toxic to crustaceans in enclosures receiving nominal cypermethrin concentrations of ]/0.13 mg/l. No EffectConcentration (NEC) and median Effect Concentration (EC50) for the total crustacean community and cladoceran andcopepod subgroups ranged between 0.02 /0.07 and 0.04 /0.17 mg/l, respectively, with copepods being less sensitive thancladocerans. The abundance of rotifers, protozoans and bacteria and the chlorophyll-a concentration of planktonic andperiphytic algae was significantly related to the concentration of cypermethrin. All groups proliferated within 2 /7 daysafter the cypermethrin application in those enclosures where the abundance of crustaceans was seriously affected bycypermethrin (i.e. ]/0.13 mg/l). We hypothesise that the proliferation of rotifers, protozoans, bacteria and algae was dueto a reduced grazer control from crustaceans and thereby mediated indirectly by cypermethrin. The results of thisexperiment provide knowledge on how an entire microplankton community may respond to pyrethroids in nature, andthe indirect effects observed on the community clearly demonstrates the necessity of multispecies field experiments inecotoxicological risk assessment
|
|
