Scaled model guidelines for solar coronagraphs' external occulters with an optimized shape.

One of the major challenges faced by externally occulted solar coronagraphs is the suppression of the light diffracted by the occulter edge. It is a contribution to the stray light that overwhelms the coronal signal on the focal plane and must be reduced by modifying the geometrical shape of the occulter. There is a rich literature, mostly experimental, on the appropriate choice of the most suitable shape. The problem arises when huge coronagraphs, such as those in formation flight, shall be tested in a laboratory. A recent contribution [Opt. Lett.41, 757 (2016)OPLEDP0146-959210.1364/OL.41.000757] provides the guidelines for scaling the geometry and replicate in the laboratory the flight diffraction pattern as produced by the whole solar disk and a flight occulter but leaves the conclusion on the occulter scale law somehow unjustified. This paper provides the numerical support for validating that conclusion and presents the first-ever simulation of the diffraction behind an occulter with an optimized shape along the optical axis with the solar disk as a source. This paper, together with Opt. Lett.41, 757 (2016)OPLEDP0146-959210.1364/OL.41.000757, aims at constituting a complete guide for scaling the coronagraphs' geometry.

Auricular acupuncture diagnosis in patients with lumbar hernia.

BACKGROUND: Auricular Acupuncture Diagnosis is a diagnostic method which is essential for the topographic identification on the auricle of the anatomical parts of the body carrying a particular ailment or dysfunction. OBJECTIVE: To identify the specific zones related to lumbar hernia in patients treated with a series of epidural infiltrations with corticosteroids. METHODS: In a consecutive group of thirty patients with lumbar hernia 2 diagnostic methods used in Auricular Acupuncture Diagnosis, Pain Pressure Test and Electric Skin Resistance Test, were applied before the first infiltration (T0), before the second and the third infiltration (T1, T2) and one week after the third infiltration (T3). The parameters, whose variations were analyzed at T0-T3, were the following: the number of points identified; the intensity of pain on a verbal rating scale and the foot-hand distance in cm with bent spine and extended knees. The identified points were reported on the Auricular Sectogram which is a validated graphic system suitable for a correct transcription of the points and indicated for a statistical analysis of their distribution on the different sectors. RESULTS: A significant association was found for some auricular areas, along the series of epidural infiltrations, with a progressive reduction in the number of tender and low electrical resistance points together with a decrease of pain and hand-foot distance. CONCLUSIONS: The auricular zones found with Auricular Acupuncture Diagnosis in our group of patients seem of clinical relevance and could be included in the complementary treatment of lumbar-sciatic pain in lumbar hernia.

Scaled-model guidelines for formation-flying solar coronagraph missions.

Stray light suppression is the main concern in designing a solar coronagraph. The main contribution to the stray light for an externally occulted space-borne solar coronagraph is the light diffracted by the occulter and scattered by the optics. It is mandatory to carefully evaluate the diffraction generated by an external occulter and the impact that it has on the stray light signal on the focal plane. The scientific need for observations to cover a large portion of the heliosphere with an inner field of view as close as possible to the photospheric limb supports the ambition of launching formation-flying giant solar coronagraphs. Their dimension prevents the possibility of replicating the flight geometry in a clean laboratory environment, and the strong need for a scaled model is thus envisaged. The problem of scaling a coronagraph has already been faced for exoplanets, for a single point source on axis at infinity. We face the problem here by adopting an original approach and by introducing the scaling of the solar disk as an extended source.

External occulter laboratory demonstrator for the forthcoming formation flying coronagraphs.

The design and optimization of the external occulter geometry is one of the most discussed topics among solar coronagraph designers. To improve the performance of future coronagraphs and to stretch their inner fields of view toward the solar limb, the new concept of coronagraphs in formation flight has been introduced in the scientific debate. Solar coronagraphs in formation flight require several mechanical and technological constraints to be met, mainly due to the large dimension of the occulter and to the spacecraft's reciprocal alignment. The occulter edge requires special attention to minimize diffraction while being compatible with the handling and integrating of large delicate space components. Moreover, it is practically impossible to set up a full-scale model for laboratory tests. This article describes the design and laboratory tests on a demonstrator for a coronagraph to be operated in formation flight. The demonstrator is based on the principle of the linear edge, thus the presented results cannot be directly extrapolated to the case of the flying circular occulter. Nevertheless, we are able to confirm the results of other authors investigating on smaller coronagraphs and provide further information on the geometry and tolerances of the optimization system. The described work is one of the results of the ESA STARTIGER program on formation flying coronagraphs ["The STARTIGER's demonstrators: toward a new generation of formation flying solar coronagraphs," in 2010 International Conference on Space Optics (ICSO) (2010), paper 39].

Ear acupuncture in the treatment of migraine attacks: a randomized trial on the efficacy of appropriate versus inappropriate acupoints.

Ear acupuncture can be a useful mean for controlling migraine pain. It has been shown that a technique called the Needle Contact Test (NCT) can identify the most efficacious ear acupoints for reducing current migraine pain through just a few seconds of needle contact. The majority of the points were located on the antero-internal part of the antitragus (area M) on the same side of pain. The aim of this study was to verify the therapeutic value of area M and to compare it with an area of the ear (representation of the sciatic nerve, area S) which probably does not have a therapeutic effect on migraine attacks. We studied 94 females suffering from migraine without aura, diagnosed according to the ICHD-II criteria, during the attack. They were randomly subdivided into two groups: in group A, tender points located in area M, positive to NCT were inserted; in group B, the unsuitable area (S) was treated. Changes in pain intensity were measured using a VAS scale at various times of the study. During treatment, there was a highly significant trend in the reduction of the VAS value in group A (Anova for repeated measures: p < 0.001), whereas no significance was observed in group B. VAS values were significantly lower in group A than in group B at 10, 30, 60 and 120 min after needle insertion. This study suggests that the therapeutic specificity of auricular points exists and is linked to the somatotopic representation of our body on the ear.

Ear acupoint detection before and after hysteroscopy: is it possible to clarify the representation of the uterus on the outer ear?

BACKGROUND: In the auricular maps introduced over the past 50 years by the French and Chinese schools, most organs and systems overlap consistently. One exception is the reproductive system, which shows a markedly different somatotopic representation-for example, for the uterus and the ovary. OBJECTIVE: To identify the distribution of points with increased tenderness to pressure or with reduced electrical resistance, on the outer ear of a group of women undergoing hysteroscopy. METHODS: For diagnostic purposes the auricles of 78 women were examined before and after hysteroscopy using a pain-pressure test and electrical skin resistance test. The points identified were transcribed onto a graphic system called Sectogram. Spatial cluster analysis was used to identify the statistically significant clusters of sectors with a higher concentration of points appearing after hysteroscopy. RESULTS: The points identified after hysteroscopy tend to be concentrated in specific areas not previously recognised and which only partially overlap with the French and Chinese representation of the uterus. CONCLUSION: When auricular acupuncture is applied to reduce discomfort during hysteroscopy, particular attention must be paid when choosing the points/areas to be stimulated, which are not only those indicated in the Chinese or French maps.

Ear acupuncture in unilateral migraine pain.

The needle contact test (NCT) is a diagnostic technique useful to identify, through the contact of the needle on the skin of the ear, the most efficacious points for reducing pain during a migraine attack. The aim of this study was to identify the most important auricular zones for pain control by applying the NCT in a group of 15 women during a unilateral attack of migraine without aura. We also assessed how effective the insertion of a semi-permanent needle in these zones was in reducing the migraine pain during the next 24 h. The most effective tender points in pain control were located on the antero-internal part of the antitragus, the anterior part of the lobe and the upper auricular concha ipsilateral to the side of pain. The insertion of a semi-permanent needle in these zones allowed stable control of the migraine pain, which occurred within 30 min and persisted at the same levels 24 h later (ANOVA for repeated measures: p < 0.01). Pain was tested by using a visual analogue scale; the values recorded were the following: 7.6 +/- 1.6 at baseline and 4.3 +/- 1.7; 4.1 +/- 1.9; 3.9 +/- 1.8; 3.4 +/- 1.8; 2.3 +/- 1.6 after, respectively, 15, 30, 60, 120 min and 24 h.

Stray-light analysis for the SCORE coronagraphs of HERSCHEL.

The HERSCHEL (Helium Resonance Scattering in the Corona and Heliosphere) suborbital mission scientific payload consists of two extreme ultraviolet (EUV) coronagraphs forming the SCORE (Sounding Coronagraph Experiment) and an EUV Sun disk imager. The mission will be of great importance for the investigation of solar wind dynamics by obtaining the first global image of the Sun (disk and corona) in the He ii30.4 nm line. The most stringent requirement for the optical design of a coronagraph is stray-light reduction. We summarize the stray-light analysis for the SCORE coronagraphs, which are characterized by an innovative optical design, optimized for stray-light reduction.

Optical design of a high-spatial-resolution extreme-ultraviolet spectroheliograph for the transition region.

A spectroheliograph dedicated to the observation of the solar disk in the extreme-ultraviolet OV spectral line at 62.97 nm is described. As demonstrated in the Skylab SO-82A spectroheliograph [Appl. Opt. 16, 870 (1977)], this line is uniquely suited to characterize solar plasma in the important 250, 000 K temperature regime. No multilayer coating or suitable filter is yet available to select this wavelength, so an optical design based on a double spectrograph with a spatial filter to remove the unwanted radiation has been developed. Analysis of the optical design shows that this instrument can obtain a 1 arcsec spatial resolution (two pixels) with a relatively high image-acquisition cadence. A preliminary tolerance analysis has been performed. A simple method of instrument alignment in visible light is also described.

Acupuncture reflexotherapy in the treatment of sensory urgency that persists after transurethral resection of the prostate: a preliminary report.

AIMS: In this study, we wanted to evaluate whether acupuncture reflexotherapy is able to treat the sensory irritative components of LUTS (lower urinary tract symptoms) that persist after transurethral resection of the prostate. METHODS: We have evaluated 42 patients, randomly selected into three groups: 14 patients received placebo, 15 patients received oxybutynin, and 13 patient were treated with electrostimulation by acupuncture reflexotherapy. RESULTS: Before treatment, the mean maximum flow rate (Qmax) was 21.0 +/- 3.2 mL/sec, the mean International Prostate Symptom Score (I-PSS) score was 12.9 +/- 4.2, the mean I-PSS Quality of Life (IPSS QoL) score was 3.6 +/- 1.2. At the first check-up performed after 3 months, we could observe that the I-PSS and QoL scores were 12.6 +/- 4.3 and 3.8 +/- 1.3 in the group who received placebo; the scores decreased to 11.1 +/- 3.2 and to 3.1 +/- 1.0, respectively, in the 15 patients treated with oxybutynin and decreased to 6.1 +/- 2.6 and 1.3 +/- 1.1, respectively, in the 13 patients who underwent acupuncture reflexotherapy. At 1-year follow-up, these parameters were practically similar. The voiding diaries allowed us to deduce that the average number of daytime voidings decreased by 8% in patients who received oxybutynin and decreased by 20% in 13 patients who underwent reflexotherapy; the average number of nocturnal micturitions decreased by approximately 20% and 60%, respectively, in patients who received oxybutynin and reflexotherapy. CONCLUSIONS: This study has pointed out that acupuncture reflexotherapy has a real benefit in patients with sensory urgency that persists after transurethral resection of the prostate.

Characterization of materials for a vacuum-ultraviolet polarization analyzer.

Astronomical measurements in the vacuum-UV spectral region (30-190 nm) require space instruments and techniques that are at the boundary between visible and x-ray techniques. In vacuum-UV polarimetry, transmission polarizers must be replaced by reflection polarizers because of the lack of transparent materials in the 30-105-nm range. The general features of a single reflection polarization analyzer for the vacuum UV are introduced and described, with particular emphasis on astrophysical applications. In particular, we discuss the trade-off conditions for optimum polarization and throughput of a single-reflection surface in the vacuum UV, introducing a quality factor parameter. The polarization performances of various reflecting materials are obtained with a reflecting vacuum-UV polarization analyzer laboratory model designed and built to measure the state of linear polarization. On the basis of a comparison of the quality factors, calcium fluoride is determined to be the best-performing material. Finally, we discuss the laboratory polarimetric characterization of the material properties for astronomical application of the polarization analyzer.