Universal method for holographic grating recording: multimode deformable mirrors generating Clebsch-Zernike polynomials.

Recording methods for making aberration-corrected holographic gratings are greatly simplified by use of a plane multimode deformable mirror (MDM) upon one of the two recording beams. It is shown that MDM compensators easily provide the superposition of many interesting active optics modes, which we have named Clebsch-Zernike modes. When we apply only a uniform loading or no loading at all onto the rear side of the MDM clear aperture, the available Clebsch-Zernike modes are made to belong to a subclass of the Zernike modes that includes the three modes of the third-order aberration theory as well as a well-defined part of the Zernike higher-order modes. Such a recording method is considered to be universal, since it does not require the use of a sophisticated optical system such as a compensator. Active optics 12-arm MDM's in the vase form have been designed from the elasticity theory. The design of six-arm MDM's is currently carried out with theoretical results. As an example of the method, the recording of three holographic gratings of the Hubble Space Telescope Cosmic Origins Spectrograph has been investigated. Substantial improvements in image quality have been found by use of a six-arm MDM as recording compensator. The result is that aberrations of much higher order can simultaneously be corrected so that the residual blur images of the spectra occupy areas approximately 10 (direction of dispersion) x 3 (cross dispersion) = 30 times smaller--also in terms of pixel number--than those obtained by our American colleagues. Therefore the active optics recording method appears to provide substantial gains in resolving power and in sensitivity: (i) For all three gratings the spectral resolution would be increased by a factor of 10, and (ii), in addition, for the two higher dispersion gratings, the limiting magnitude on the sky appears to be increased by a magnitude of approximately 1-1.2.

High-dispersion spherical holographic gratings in a modified rowland mounting.

For holographic gratings requiring an extreme dispersion, I consider a modified Rowland mounting, in which the recording laser sources are moved away from the grating, to reduce the uncorrected higher-order aberrations. In addition, I choose the geometric parameters such that first-type coma is corrected. Then a plane multimode deformable mirror (MDM) or two auxiliary spherical holographic gratings (R3 device) are used to aberrate the grating's recording sources; correction up to the fourth order is sufficient to obtain high image quality. Applied to the FUSE-Lyman (FUSE is Far Ultraviolet Spectroscopic Explorer) grating, with a groove density as high as 5767 grooves/mm, these recording devices produce a resolution (chromatic resolving power) as great as 611,000 with the MDM and 3,030,000 with the R3 device. These results far exceed the specified performance of 30,000. Since diffraction limits the resolution to 482,000, the images are diffraction limited with both devices.

Recording high-dispersion spherical holographic gratings in a modified Rowland mounting by use of a multimode deformable mirror.

To reduce the uncorrected higher-order aberrations for holographic gratings requiring an extreme dispersion, we have modified the Rowland mounting by moving the recording laser sources away from the grating. Then, with a multimode deformable plane mirror to record the grating, the correction of all the aberrations up to the fourth order inclusive is found sufficient to obtain a high-quality image. Applied to the FUSE-LYMAN grating, with a groove density of as much as 5740 grooves/mm, for which a resolution of 30,000 was required, this new recording device produces a resolution from 139,000 to 222,000 over the spectral range.

Effects of PVC bags sterilization process on the 5-fluorouracil stability.

The stability and compatibility of 5-fluorouracil (5-FU) in undiluted or diluted admixtures stored in beta-radiation sterilized portable poly(vinyl chloride) (PVC) infusion bags were investigated. Admixtures containing 5-FU 50 mg ml(-1) not diluted or 25 mg ml(-1) diluted in 0.9% sodium chloride injection were placed in 100 or 250 ml empty PVC reservoirs sterilized initially by beta-irradiation. They were protected from light and placed at 37 degrees C. Two ml quantities were withdrawn immediately after preparation and after storage for 1, 2, 3, 4, 5, 6, 7 and 14 days. For each condition, samples from each admixture were tested for drug concentration by stability-indicating high-performance liquid chromatography. The admixtures were also monitored for precipitation, color change and pH. Evaporative water loss from the containers was also measured. 5-FU was compatible with PVC containers in all tested conditions for 14 days. No loss of drug and no color change were detected throughout the storage period. pH values were stable and neither precipitation nor loss of water through the reservoirs was observed when drug 50 or 25 mg ml(-1) (diluted using 0.9% sodium chloride) was stored in 100 ml capacity polyvinyl PVC bags. However, when stored in 250 ml capacity PVC bags, the 5-FU solution showed precipitation after 13 and 14 days of storage, but no drug loss was detected due to a substantial loss of water. The precipitation of the drug was due to the decrease of pH induced by the dehydrochlorination of PVC during beta-irradiation leading to the formation of hydrochloric acid in solution. Differences observed between 100 and 250 ml capacity bags can be explained by the greater area of PVC present in 250 ml reservoirs, and consequently more HCl formed. Finally, more plasticizer, di-(2-ethylhexyl) phthalate (DEHP), was then detected in drug solutions stored in 250 ml PVC bags. So, we recommend the use of 100 ml bags to store 5-FU at longer storage times and higher temperatures.

Theory and computation of three cosmic origin spectrograph aspheric gratings recorded with a multimode deformable mirror.

The theory of three Cosmic Origin Spectrograph holographic gratings recorded with a deformable plane mirror is presented. Their working conditions are severe, since they have to correct the strong spherical aberration and the field astigmatism of the Hubble Space Telescope. Recorded on aspherized substrates, the gratings produce images that are diffraction limited with regard to spectral resolution.

Third-generation holographic Rowland mounting: fourth-order theory.

The third-generation holographic Rowland mount consists of a Rowland-mounted, optimally recorded holographic spherical grating, referred to as an optimized Rowland grating (ORG), whose recording sources are aberrated by two auxiliary ORG's. The main purpose of this mount is to avoid any aspherical surface while providing control over all the parameters needed to correct the aberrations up to and including the fourth order. Earlier [Appl. Opt. 30, 4019-4025 (1991)], we considered the case of a moderate coma c2. We now give the fourth-order theory, apply it to the high-dispersion (4600 grooves/mm) grating considered previously, and obtain for it diffraction-limited images.

[Analysis of hematopoietic growth factor prescriptions in 19 french cancer centers]. / Analyse de la prescription de facteurs de croissance hématopoïétique dans 19 centres anticancéreux français. Groupe de pharmaciens de la Fédération nationale des centres de lutte contre le cancer.

Medical prescription of hematopoietic growth factors (HGF) was analysed in 19 anticancer french centers during 2 months. About 4% of anticancer chemotherapeutic cycles prescribed during this period were supported by HGF prescription. The mean duration of treatment was 8 days. Among the 755 collected prescriptions, two tumor localizations represented about 50% of the prescriptions: malignant non Hodgkin lymphomas and breast cancer. The other main localizations concerned adult or pediatric soft tissue sarcomas (18%), testicular cancer (7%) and gynecologic tumors (6%). The prescription for primary prophylaxis for febrile neutropenia remains the main use of HGF (44%). The respect of the guidelines established by the F|d|ration nationale des centres de lutte contre le cancer was analyzed. Overall, 66% of the prescriptions were in adequation with these guidelines. Whereas the consommation of HGF decreased in the 19 considered institutions, it did not reach a plateau and could decrease in institutions which are awaked to the international and national recommendations.

Recording method for obtaining high-resolution holographic gratings through use of multimode deformable plane mirrors.

We propose a new way of recording in which a spherical blank and a deformable mirror are used to obtain high-resolution holographic gratings. The reflection of one of the two laser recording waves upon this mirror provides the deformations necessary to image correction to as much as seventh-order aberrations inclusively.

Theory of spherical holographic gratings recorded by use of a multimode deformable mirror.

We present the theory of spherical holographic gratings recorded by use of a deformable plane mirror and consider its application to the optimized Rowland Mounting. We illustrate the efficiency of such a mounting by computing two high-resolution gratings (3800 grooves/mm) with f/24 and f/10 apertures.

Illustration of the use of multimode deformable plane mirrors to record high-resolution concave gratings: results for the Cosmic Origins Spectrograph gratings of the Hubble Space Telescope.

To illustrate the efficiency of using a deformable plane mirror to record holographic gratings, we have computed the three gratings for the Cosmic Origins Spectrograph. Their working conditions are severe, since they have to correct the residual spherical aberration of the Hubble Space Telescope. Nevertheless, all images obtained are largely diffraction limited with regard to the resolution.