Figure Correction Research Articles

Adjustable X-ray optics: thin-film actuator measurement and figure correction performance

Adjustable X-ray optics: thin-film actuator measurement and figure correction performance

Sub-nanometre quality X-ray mirrors created using ion beam figuring.

Ion beam figuring (IBF) is a powerful technique for figure correction of X-ray mirrors to a high accuracy. Here, recent technical advancements in the IBF instrument developed at Diamond Light Source are presented and experimental results for figuring of X-ray mirrors are given. The IBF system is equipped with a stable DC gridded ion source (120 mm diameter), a four-axis motion stage to manipulate the optic, a Faraday cup to monitor the ion-beam current, and a camera for alignment. A novel laser speckle angular measurement instrument also provides on-board metrology. To demonstrate the IBF system's capabilities, two silicon X-ray mirrors were processed. For 1D correction, a height error of 0.08 nm r.m.s. and a slope error of 44 nrad r.m.s. were achieved. For 2D correction over a 67 mm × 17 mm clear aperture, a height error of 0.8 nm r.m.s.and a slope error of 230 nrad r.m.s. were obtained. For the 1D case, this optical quality is comparable with the highest-grade, commercially available, X-ray optics.

Correction: Bianchi et al. Quadrotor Trajectory Control Based on Energy-Optimal Reference Generator. Drones 2024, 8, 29

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ASSESSMENT AND DETERMINATION OF MOTIVATIONAL FACTORS FOR WEIGHT LOSS AND INDICATORS OF THE FUNCTIONAL STATE OF OBESE WOMEN IN THE REHABILITATION PROCESS

Resume
 The rapid spread of obesity emphasizes the relevance of studying this issue and requires a detailed investigation, justification, and development of an appropriate physiotherapeutic intervention program tailored to the individual needs of each patient. Therefore, we have decided to dedicate our research to determining the motivational factors for weight loss in these women and analyzing the indicators of their functional status before undergoing a physiotherapeutic intervention program.
 The aim of the research is to develop a comprehensive program of physiotherapeutic interventions for women with obesity based on the study of motivational factors and analysis of existing approaches to obesity treatment, as well as to evaluate its effectiveness.
 Materials and methods. The study included a theoretical analysis of scientific and methodological literature, as well as instrumental examination methods using the remote body composition measuring method BC-418MA TANITA. A total of 68 women aged between 36 and 55 years (mature age) with different degrees of obesity participated in the research. They were divided into two groups: the control group (CG, n=34) and the experimental group (EG, n=34). The control group received rehabilitation measures following the standard treatment protocol, which included dietary №8 and physical exercises. The experimental group participated in a developed and pilot-tested physiotherapeutic intervention program, which included a complex of exercises aimed at improving the functional status of women, considering individual preferences, a modified method of dietary therapy (based on dietary table №8 according to Pevzner), and keeping a motivational journal. The study was conducted at the Sport Life fitness club in Kyiv, located at Mayakovskogo Avenue, 46, Troieshchyna district. The research course lasted for three months.
 Research results. Based on the obtained data, it is evident that both groups experienced a decrease in total body weight and a reduction in specific weight of adipose tissue by the end of the 3rd month. However, it is noteworthy that the level of BMI reduction after the developed program was significantly higher in the experimental group. After completing the course of comprehensive physical therapy, significant reductions in body mass index (BMI) were observed in both groups, with the control group showing a BMI of 29,66 ± 0,9 kg/m2 and the experimental group showing a BMI of 28,03 ± 0,5 kg/m2, (p<0,05).
 Conclusions. The results of the survey of the studied group of women indicate that the vast majority of respondents – 73,0% chose the health factor as the main motivator for losing weight. For 54,4% of women, having a good appearance, especially physical attractiveness, can be achieved by correcting body weight.. The results of the conducted research give grounds for asserting that the use of the diet therapy method and kinesiotherapy exercises developed by us as part of the physical rehabilitation program developed for women of the second mature age with obesity, led to a safe reduction of body weight and the fat component, and the achievement of individually planned results of figure correction. The advantages of the developed program are confirmed by the results of own research.

Nanometer flat blazed x-ray gratings using ion beam figure correction.

With the development of nanometer accuracy stitching interferometry, ion beam figuring (IBF) of x-ray mirrors can now be achieved with unprecedented performance. However, the process of producing x-ray diffraction gratings on these surfaces may degrade the figure quality due to process errors introduced during the ruling of the grating grooves. To address this challenge, we have investigated the post-production correction of gratings using IBF, where stitching interferometry is used to provide in-process feedback. A concern with ion beam correction in this case is that ions will induce enough surface mobility of atoms to cause smoothing of the grating structure and degradation of diffraction efficiency. In this study we found however that it is possible to achieve a nanometer-level planarity of the global grating surface with IBF, while preserving the grating structure. The preservation was so good, that we could not detect a change in the diffraction efficiency after ion beam correction. This is of major importance in achieving ultra-high spectral resolution, and the preservation of brightness for coherent x-ray beams.

Plasma Figure Correction Method Based on Multiple Distributed Material Removal Functions.

In the process of plasma figure correction for a quartz sub-mirror, the plasma parallel removal process and ink masking layer are combined for the first time. A universal plasma figure correction method based on multiple distributed material removal functions is demonstrated, and its technological characteristics are analyzed. Through this method, the processing time is independent of the workpiece aperture, which saves time for the material removal function to scan along the trajectory. After seven iterations, the form error of the quartz element is converged from the initial figure error of ~114 nm RMS to a figure error of ~28 nm RMS, which shows the practical potential of the plasma figure correction method based on multiple distributed material removal functions in optical element manufacturing and the possibility of becoming a new stage process in the optical manufacturing chain.

Figure correction of a Wolter mirror master mandrel by organic abrasive machining.

In this study, figure correction of a master mandrel of a Wolter mirror by organic abrasive machining (OAM) was demonstrated. In OAM, a flow of slurry, dispersed with organic particles, locally removes the surface of a workpiece in contact with a rotating machining tool. A computer-controlled machining system was used to perform the selective removal of a fused silica surface at a spatial resolution of 200 µm. A master mandrel of a Wolter mirror for soft x-ray microscopes was fabricated with a figure accuracy of <1nm root mean square, which is sufficient for diffraction-limited imaging at a wavelength of 10nm.

Fabrication of ultrashort sub-meter-radius x-ray mirrors using dynamic stencil deposition with figure correction

This paper presents nanometer-scale production and metrology methods for elliptic-cylindrical x-ray mirrors with an unprecedentedly small tangential radius of curvature of 160 mm. Sub-millimeter-scale figure correction is conducted based on dynamic stencil deposition. The deposition flux through one or two shadow masks is examined by a comparison to a simple model. The masked deposition flux distribution is improved, leading to film thickness profiles that are 50 times sharper in terms of aspect ratio than those obtained using existing differential deposition approaches. Surface roughness deterioration is also effectively suppressed. A 2-mm-long 160-mm-radius mirror is produced with a width of 10 mm and measured using simple interferometry. The results are confirmed by conventional mirror metrology, contact profilometry, and x-ray ptychography. The x-ray focusing profile is diffraction-limited with a 142-nm focus size at a photon energy of 300 eV. The proposed methods have the potential to enhance the ultraprecise fabrication of highly curved mirrors, thus benefiting nanoscale photon-hungry x-ray techniques.

Surface figure correction with roughness reduction using carbon-doped platinum film for high-precision X-ray mirror fabrication.

To obtain the surface shape of an X-ray mirror with high precision, a differential deposition method was used instead of a direct removal method. To modify the mirror surface shape using the differential deposition method, it is necessary to coat it with a thick film, and the co-deposition method is used to suppress the increase in surface roughness. The addition of C to the Pt thin film, which is often used as an X-ray optical thin film, resulted in lower surface roughness compared with that with the Pt coating alone, and the stress change according to the thin film thickness was evaluated. Differential deposition controls the speed of the substrate during coating based on continuous motion. The stage was controlled by calculating the dwell time through deconvolution calculations based on the accurate measurement of the unit coating distribution and target shape. We successfully fabricated an X-ray mirror with high precision. This study indicated that an X-ray mirror surface could be manufactured by modifying the surface shape at a micrometer level through the coating. Changing the shape of existing mirrors can not only result in the manufacture of high-precision X-ray mirrors but also improve their performance.

Abrasive slurry jet machining system using polyurethane@silica core-shell particles for internal surfaces of axisymmetric x-ray mirrors.

Abrasive machining has been used for inner surface processing of various hollow components. In this study, we applied an in-air fluid jet as a precision machining method for the inner surface of an axisymmetric x-ray mirror whose inner diameter was less than 10mm. We employed an abrasive with a polyurethane@silica core-shell structure, which has a low density of about 1.2 g/cm3 and a relatively large particle size of about 15 µm. By using this abrasive, a practical removal rate and a smooth machined surface were simultaneously obtained. We performed figure corrections for an axisymmetric mirror and improved the circumferential figure accuracy to a sub-10nm root mean square level. To evaluate the machining performance in the longitudinal direction of the ellipsoidal surface, we also performed periodic figure fabrication on the inner surface of a 114 mm-long nickel ellipsoidal mirror. X-ray ptychography, an optical phase retrieval method, was also employed as a three-dimensional figure measurement technique of the mirror. The wavefield of the x-ray beam focused by the processed ellipsoidal mirror was observed with the ptychographic system at SPring-8, a synchrotron radiation facility. The retrieval calculations for the wavefront error confirmed that a sinusoidal waveform with a period of 12mm was fabricated on the mirror surface. These experimental results suggest that a nanoscale figure fabrication cycle for the inner surface consisting of jet machining and wavefront measurement has been successfully constructed. We expect this technique to be utilized in the fabrication of error-free optical mirrors and various parts having hollow shapes.

Compression microvibration: Experience of using the method for the physiotherapeutic treatment of cellulite

BACKGROUND: Cellulite treatment and figure correction are among the most demanded requests in aesthetic medicine centers, which determines the high social and medical and economic significance of the problem, stimulates the active use of modern medical technologies. AIM: evaluation of the effectiveness of the non-invasive method of compression microvibration in the treatment of cellulite in women of peri- and postmenopausal age. MATERIAL AND METHODS: A single center prospective cohort study was conducted in which 27 female volunteers with mild to moderate gynoid lipodystrophy took part. All participants completed the Endospheres Therapy course according to the standard protocol: 12 procedures for 60 minutes twice a week using the Endospheres Therapy Body compression microvibration apparatus. Before and after the completion of the course of procedures, anthropometric parameters (linear and weight dimensions of the body) were measured, fat, lean, active cellular and skeletal muscle mass, specific basal metabolism, total and extracellular fluid, bioimpedance phase angle were evaluated using bioimpedancemetry. To obtain a subjective assessment of the effectiveness and quality of the procedures received, all participants underwent anonymous testing. RESULTS: Under observation were 27 women, who made up 3 clinical groups of 9 women each in accordance with age criteria: group 1 ― before menopause (age 4049 years); group 2 ― menopause (5059 years) and group 3 ― postmenopause (6069 years). After the Endospheres Therapy course, the mean group body mass index values did not change, however, a weight loss of 3.47.4 kg, a decrease in waist and hips by 2.23.02.5 cm, 4.15.36.3 cm in the respective age groups. In the first group of participants, the fat mass index decreased by 16.4% (p 0.005), active cell mass increased by almost 15% (p 0.005), skeletal muscle mass ― by 13% (p 0.005), the specific basic metabolism ― by 10% (p 0.005), the value of phase angle after the course Endospheres Therapy increased statistically significantly by 16% (p 0.05). In other age groups, bioimpedance measurements were similar, but less pronounced. After the procedures, in some cases, study participants reported a slight tingling/squeezing sensation, slight muscle soreness, reminiscent of the state after exercise, and temporary slight redness of the skin. CONCLUSION: The results obtained allow us to state the effectiveness and safety of the use of Endospheres Therapy in the treatment of cellulite, as a pathogenetically substantiated method of physiotherapy that affects the improvement of the skin condition, the transformation of the fat component, the increase in cell metabolism, muscle tone, stimulation of lymphatic drainage and tissue trophism.

Analysis of stresses and shape changes in thin substrates with stressed film patterning using femtosecond laser micromachining

The accurate, high-throughput fabrication of light weight optical systems for applications like next-generation space telescopes and semiconductor wafers is both crucial and challenging. A potential solution is to first fabricate thin substrates with traditional methods, then apply surface stress to bend them into desired shapes to correct residual height errors. We have developed a stress-based figure correction method for thin silicon mirrors using a femtosecond laser micromachining technique to generate patterned stress fields, through the removal of selective stressed film regions and adjacent substrate regions. In this paper, we present an in-depth analysis for the laser-induced stresses and resulting shape changes of thin mirrors due to the periodic patterning of a stressed film (silicon oxide) on silicon substrates using femtosecond laser surface ablation. Experimental results are presented, and a 3D finite element model (FEM) is developed to study the substrate curvature in directions parallel and perpendicular to the patterned troughs in the substrates. We simulate the stress relief process in the thin-film/substrate system, and the numerical predictions compare reasonably well with curvature measurements for several different geometrical combinations of depth, width and spacing of the patterned troughs, achieving >82% quantitative agreement with the experiments. It is also shown in the simulations that certain geometries of patterned troughs induce more dramatic shape changes and counter-intuitive reversals of curvature in the direction perpendicular to the troughs, and a qualitative explanation involving the Poisson effect is presented. The 3D finite element methods and findings of this paper can be used to determine the optimal parameters of the stressed film patterns for figure correction of thin telescope mirrors and other types of thin substrates used in the semiconductor industry.

Figure Correction of a Quartz Sub-Mirror for a Transmissive Diffractive Segmented Telescope by Reactive Ion Figuring

A quartz sub-mirror was figure-corrected in a parallel removal process for the first time. An Reactive Ion Figuring (RIF) process with a simple and universal masking method was demonstrated, and the 350-mm quartz sub-mirror was figure-corrected from the initial figure error of ~23 nm RMS to the final figure error of ~8 nm RMS in total effective figuring time of ~52 minutes after 4 iterations, which exhibited the actual potential of RIF on the figure-correction of quartz optical elements and the possibility on applying RIF to meet the requirement of mass production for sub-mirrors of transmissive diffractive segmented telescopes.

Femtosecond laser micromachining for stress-based figure correction of thin mirrors

The fabrication of a large number of high-resolution thin-shell mirrors for future space telescopes remains challenging, especially for revolutionary mission concepts such as NASA’s Lynx X-ray Surveyor. It is generally harder to fabricate thin mirrors to the exact shape than thicker ones, and the coatings deposited onto mirror surfaces to increase the reflectivity typically have high intrinsic stress that deforms the mirrors further. Since the rapid development of femtosecond laser technologies over the last few decades has triggered wide applications in materials processing, we have developed a mirror figure correction and stress compensation method using a femtosecond laser micromachining technique for stress-based surface shaping of thin-shell x-ray optics. We employ a femtosecond laser to selectively remove regions of a stressed film that is grown onto the back surface of the mirror, to modify the stress states of the mirror. In this paper, we present experimental results to create both isotropic and anisotropic stress states on thin flat silicon mirrors with thermal oxide ( S i O 2 ) films using femtosecond lasers. We show that equibiaxial stress can be generated through uniformly micromachined holes, while non-equibiaxial stress arises from the ablation of equally spaced troughs. We also present results from strength tests to show how this process minimally affects the strength of mirrors. These developments are beneficial to the high-throughput correction of thin-shell mirrors for future space-based x-ray telescopes.

Erratum: Correction of Figures. Association between the Blautia/Bacteroides Ratio and Altered Body Mass Index after Bariatric Surgery

Erratum: Correction of Figures. Association between the Blautia/Bacteroides Ratio and Altered Body Mass Index after Bariatric Surgery

Fabrication of soft x-ray monolithic Wolter mirror based on surface scanning measurement using touch probe.

The monolithic Wolter mirror is an ideal optical device for focusing soft x rays to a submicron-sized spot, with the advantages of high efficiency, large acceptance, achromaticity, and robustness to alignment error. The fabrication process for this type of mirror has not been established because of the difficulty in highly accurate figure measurement of free-form surfaces with small radii of curvature and steep profiles. In this study, we employed tactile scanning measurement for surface characterization to fabricate a high-precision Wolter mirror. First, it was demonstrated that the touch probe measurement did not leave scratches on the raw surface of the mirror substrate. Next, the measurement capability of the surface profiler was assessed, and the data analysis conditions were determined. Finally, the Wolter mirror was fabricated through repeated figure correction based on the tactile measurement, and the figure error of the final surface was evaluated. Wave-optical simulations that used this error as reference suggested that the size of the beam focused by the mirror was equivalent to the theoretical value at 1000 eV. The reflected image with uniform intensity distribution obtained at SPring-8 also revealed the effectiveness of the present fabrication approach based on tactile measurement.

Stress tensor mesostructures for deterministic figuring of thin substrates

Accessing the immense value of freeform surfaces for mass-sensitive applications such as space optics or metaform optical components requires fabrication processes that are suited to figuring thin substrates. We present stress tensor mesostructures for precisely correcting figure errors, even after microstructures or coatings have been applied to the optical surface. These mesostructures can be fabricated using standard semiconductor fabrication equipment. We introduce three different mesostructure types that each spatially control the three required stress tensor components over the surface of thin substrates, each offering relative advantages. We patterned all three mesostructures on the backsides of silicon wafers to demonstrate freeform figure generation and correction. Stress tensor mesostructures can enable low-cost accurate figuring of the thin substrates that will become increasingly important for lightweight and metasurface optics.

Organic abrasive machining system for optical fabrication with 0.1-mm spatial resolution.

High-precision optics for short-wavelength regions, such as x rays and extreme ultraviolet light, generally require nanometer-level figure accuracy on their surfaces. Such optics are finished via a numerically controlled figure correction process in which the dwelling time of the machining tool on the workpiece is controlled. Due to the limitation of the machined spot size, it is difficult to remove mid-spatial-frequency (1 to 10mm-1) errors on an optical surface. To realize a high-spatial-resolution figure correction process for high-precision optics, we have been developing the organic abrasive machining (OAM) technique, which can generate a 100 µm machined spot using a small elastic rotation tool in a slurry that includes acrylic particles. In this study, an OAM apparatus that can measure the machining load was constructed. The effects of the machining and slurry conditions were investigated and high-spatial-resolution machining on a flat glass substrate was demonstrated. The root-mean-square roughness of the surface after OAM processing was below 0.2nm. Patterns with a minimum line and space size of 100 µm were successfully fabricated.

Correction: Systematic identification of celastrol-binding proteins reveals that Shoc2 is inhibited by celastrol.

The authors of the original article “Systematic identification of Celastrol-binding proteins reveals that Shoc2 is inhibited by Celastrol” (Biosci Rep (2018) 38(6), DOI: 10.1042/BSR20181233) would like to correct Figure 1 of their article. During figure preparation for the submission of their manuscript, their NC image file had inadvertently been used twice, and the DMSO image had been labelled as the 0.1 image in error. The correct version of Figure 1C is present in this Correction. The authors apologise for the errors made and for any inconvenience caused. They confirm that these figure corrections do not impact the data interpretation and conclusions of their paper.

Using mobile applications as one of the means of a healthy lifestyle

The article systematizes data on the use of the most popular mobile applications designed to increase the level of motivation of student youth. We analyzed Internet resources in order to analyze the features and benefits of free and paid mobile applications that are available for gadgets on the operating system iOS and Android. We conducted a questionnaire which aimed to determine the motives for the use of modern mobile applications by students of different ages. Thus, the use of mobile gadgets and applications to them increases the motivation to exercise, stimulates young people's interest in their own health. All applications are aimed at leading a healthy lifestyle, improving health, improving physical fitness and increasing motivation to exercise. Most young people use mobile applications in the following areas: general physical training; walking, running; strength training; control of physical fitness; proper nutrition; water balance. Among the motives of young people for the use of mobile applications in the process of physical culture and health classes are identified: figure correction, lack of time to visit the gym. Mobile applications help to adhere to the schedule, plan and mode of training, diversify daily activities and help control water balance and product selection.