Brain effect mechanism of lever positioning manipulation on LDH analgesia based on multimodal MRI: a study protocol.

INTRODUCTION: The clinical symptoms of Lumbar Disc Herniation (LDH) can be effectively ameliorated through Lever Positioning Manipulation (LPM), which is closely linked to the brain's pain-regulating mechanisms. Magnetic Resonance Imaging (MRI) offers an objective and visual means to study how the brain orchestrates the characteristics of analgesic effects. From the perspective of multimodal MRI, we applied functional MRI (fMRI) and Magnetic Resonance Spectrum (MRS) techniques to comprehensively evaluate the characteristics of the effects of LPM on the brain region of LDH from the aspects of brain structure, brain function and brain metabolism. This multimodal MRI technique provides a biological basis for the clinical application of LPM in LDH. METHODS AND ANALYSIS: A total of 60 LDH patients and 30 healthy controls, matched by gender, age, and years of education, will be enrolled in this study. The LDH patients will be divided into two groups (Group 1, n = 30; Group 2, n = 30) using a random number table method. Group 1 will receive LPM treatment once every two days, for a total of 12 times over 4 weeks. Group 2 will receive sham LPM treatment during the same period as Group 1. All 30 healthy controls will be divided into Group 3. Multimodal MRI will be performed on Group 1 and Group 2 at three time points (TPs): before LPM (TP1), after one LPM session (TP2), and after a full course of LPM treatment. The healthy controls (Group 3) will not undergo LPM and will be subject to only a single multimodal MRI scan. Participants in both Group 1 and Group 2 will be required to complete clinical questionnaires. These assessments will focus on pain intensity and functional disorders, using the Visual Analog Scale (VAS) and the Japanese Orthopaedic Association (JOA) scoring systems, respectively. DISCUSSION: The purpose of this study is to investigate the multimodal brain response characteristics of LDH patients after treatment with LPM, with the goal of providing a biological basis for clinical applications. TRIAL REGISTRATION NUMBER: https://clinicaltrials.gov/ct2/show/NCT05613179 , identifier: NCT05613179.

Two-dimensional stretchable blazed wavelength-tunable grating based on PDMS.

This paper reports a two-dimensional stretchable blazed wavelength-tunable grating based on polydimethylsiloxane (PDMS). In the elastic range, stretch the grating along (Y-axis) and perpendicular to (X-axis) the grating line, fix the position of the +1st-order spot to maintain the grating period, and only change the groove angle to tune the blazed wavelength. By stretching the grating up to 20% of the Y-axis, and 5.2% of the X-axis, the groove angle is reduced by 1.33°, and the blazed wavelength of the first-order diffraction shifts toward the short-wave direction by 42.3 nm. The sensitivity of a spectrometer can be enhanced by tuning the blazed wavelength of the PDMS grating to the wavelength of the spectrum peak under observation in the bands from 460.8 nm to 503.1 nm.

Analytical design of a high-performing +1st order diffraction convex grating imaging spectrometer.

A novel concentric spectrometer having one convex grating and one concave mirror, working at ${+}{1}$+1st order diffraction, and with a small size, high resolution, and high diffraction efficiency, is proposed. It can simultaneously achieve high resolution and compactness by increasing the grating groove density. A compact spectrometer operating at a wavelength of 740-790 nm with an excellent imaging quality is designed. Its spectral resolution reaches 0.049 nm, and its diffraction efficiency improves by 27% compared to the conventional Offner spectrometer with convex grating working at ${-}{1}$-1st order diffraction. This is suitable for small, light, and low-cost atmospheric gas monitoring satellites.

Low-stray-light concave holographic gratings processed by combining the methods of photoresist hot-melting and oxygen-ion ashing.

The principal motivation for this paper is to reduce stray light and line roughness in concave holographic gratings (CHG). Compared with other previously reported line-smoothing grating techniques such as dynamic-exposure near-field holography, we successfully improve the line smoothing of CHG to approximately 10 nm from 2 nm. Our method uses optimization technologies and a combination of photoresist hot-melting (PHM) and oxygen-ion ashing (OIA), thereby improving the degree of stray light before and after optimization by one order of magnitude; the level processed by OIA, PHM, and OIA successively is ${7.85} \times {{10}^{ - 5}}$7.85×10-5. Combining the two technologies, we achieve lower stray light and straighter groove lines for the concave gratings, which is more effective, easy to implement, and incurs a low cost.

Optimized multielement accommodative intraocular lens with a four-freeform-surface Alvarez lens and a separate aspheric lens.

This paper proposes an accommodative intraocular lens (IOL), which consists of a two-element Alvarez lens and an aspheric lens for changing focal power and refractive power, respectively. The four-freeform-surface Alvarez lens is optimized for a multiple field of view; further, the aspheric lens also corrects the aberrations induced by the corneal asphericity of the human eye over the whole range of accommodation. A simulation using optical design software demonstrates its excellent performance in that the values of the modulation transfer function at 100 cycles/mm all reach ∼0.4 with a ±5° field of view for 3 and 5 mm pupils.

Multifacet echelle grating for intensity broadening on spectral plane fabricated by rotating ion-beam etching.

This paper describes a new type of multifacet echelle grating (MFEG) for use in an echelle spectrometer. This new type of echelle grating broadens the spectral distribution on the spectral plane. We built a geometric model of MFEG to analyze the influence of the blaze angle and number of facet shapes on the spectral evolution. A dual-facet echelle grating and a four-facet echelle grating with different parameters were fabricated by rotating ion-beam etching with a self-shadowing rotating mask, based on the existing single-facet echelle grating (SFEG) with a line density of 52.7 g/mm and a blaze angle of 63.5°. The distributions of diffraction efficiency for different orders were measured with a He-Ne laser (632.8 nm); furthermore, these echelle gratings were applied in an echelle spectrometer (ICP-OES, Plasma2000), and testing spectra were obtained. The experimental results demonstrate that the MFEG can broaden the intensity distribution on the spectral plane, overcoming the weak spectral margin signal of SFEG spectrometers.

Research on Straightness Error Compensation of Grating Ruling Machine.

Echelle grating is a kind of special diffraction grating. Working with high diffraction orders and big diffraction angle, which has the advantages of high resolution and full wave shining. It has been widely used in high-end spectrum instrument, which greatly promoted the development of aerospace, astronomy, medical, military, environment and other cutting-edge technology. However, professional scoring system needs to be customized, and the price is very expensive. The use of sophisticated ultra precision machining equipment to process in the ladder grating can greatly reduce the preparation cost of the mother plate of the ladder grating. Due to the bad straightness and high accumulative error of ultra precision single point diamond lathe, it can't satisfy the demand of preparation when preparing the echelle grating, casuing the bad diffraction wave front. In order to reduce the straightness error, this paper comes up with the error compensation for the single point diamond lathe. Firstly, we make the first compensation based on the accumulative error curve. When the compensation ratio is 0.75 to 0.85, the peak valley value (pv) of the diffraction wave front is about 400 nm, reaching its greatest effect of the first straightness compensation. Secondly, we make the straightness compensation according to the diffraction wave front curve of the blazed order. The pv of the diffraction wave front is about 83nm. The results show that the diffraction wave front is greatly improved which is beneficial to improve the quality of the grating, and has a guiding role in the actual grating characterization.

[The research of UV-responsive sensitivity enhancement of fluorescent coating films by MgF2 layer].

A low cost and less complicated expansion approach of wavelength responses with a Lumogen phosphor coating was adopted, as they increased the quantum efficiency of CCD and CMOS detectors in ultra-violet by absorbing UV light and then re emitting visible light. In this paper, the sensitivity enhancement of fluorescence coatings was studied by adding an anti-reflection film or barrier film to reduce the loss of the scattering and reflection on the incident interface. The Lumogen and MgF2/Lumogen film were deposited on quartz glasses by physical vacuum deposition. The surface morphology, transmittance spectrum, reflectance spectrum and fluorescence emission spectrum were obtained by atomic force microscope (AFM), spectrophotometer and fluorescence spectrometer, respectively. The results indicated that MgF2 film had obvious positive effect on reducing scattering and reflection loss in 500-700 nm, and enhancing the absorption of Lumogen coating in ultraviolet spectrum. Meanwhile, the fluorescent emission intensity had a substantial increase by smoothing the film surface and thus reducing the light scattering. At the same time, the MgF2 layer could protect Lumogen coating from damaging and contamination, which give a prolong lifetime of the UV-responsive CCD sensors with fluorescent coatings.

[Performance comparison of coronene film for UV-CCD prepared by spin-coating and physical vapor deposition].

In the present paper, the methods of spin-coating and physical vapor deposition (PVD) were researched to prepare the coronene film for UV-CCD, and their properties were characterized and compared with each other. The results of the experiment show that the process of spin-coating is relatively simple, which takes advantage of materials and retains the inherent crystal structure of coronene. However, the roughness of the film is a little more than that of PVD method; the film prepared by PVD method can absorb ultraviolet more effectively and then emits fluorescence with more intensity. Compared with the method of spin-coating, the surface of PVD film is more smoothly, and the process of thermal evaporation changes the crystal structure of coronene and forms another new crystalline state according to the XRD graph. While the whole process of PVD is morecomplex and it needs larger cost of production than spin-coating method. Besides, the comparison research work provided theoretical direction for preparing the photoluminescence down-conversion film under different requirements, such as fluorescence intensity, surface roughness and cost of production.

[Retrospective analysis for clinical and histopathological characteristics of basal cell carcinoma in 418 patients].

OBJECTIVE: To investigate the clinical and histopathological characteristics of basal cell carcinoma (BCC) in Chinese patients. METHODS: Clinical and pathological data of BCC confirmed by histology from 2010 to 2012 in Peking University First Hospital were retrospectively analyzed. RESULTS: Among 418 patients enrolled, the male/female ratio was 0.77:1. The average age was (65.39±13.51) years. Among the patients younger than 60 years who occupied 29% of all the cases, the male/female ratio was 1.16:1. In terms of the histology subtypes of the BCCs, 81.8% were nodular, followed by superficial (9.8%), and the others were in very small proportion. The head and face were the most common sites of BCC (86.6%). All morpheaform subtypes, and the majority of the nodular subtypes were located on the head and face, whereas the trunk and extremities were the most common locations for the others. Clinically, 86.6% of the BCC were pigmented and 80.4% were not ulcerated. The diagnostic accordance rates of BCC on the head and face (84.7%) and on the trunk (79.1%) were higher than those on the extremities (46.2%, P<0.05). CONCLUSION: The most clinical and histopathological characteristics of our cases were similar to those of Caucasian. This study displays some unique characteristics. The young and middle aged patients occupied relative higher proportion, and their gender ration was different from that of the aged group. Tumor with hyperpigmentation was popular and few cases were ulcerated. In this study, multiple BCC cases were seldom, and the BCC patients with nevus sebaceous were older than those in other reports. The research of the diagnostic accordance rates of BCC revealed that both doctors and patients should pay more attention to BCC.

[General calculation method of diffraction efficiency of concave blazed gratings].

In order to make diffraction energy of concave gratings more concentrated in the desired order, the present paper puts forward that the concave blazed grating with variable groove angles could be fabricated on the concave substrates by mechanical ruling method, and the theoretical method of simultaneously calculating the diffraction efficiency in the main section and non-main section is deduced by using Fresnel-Kirchhoff's diffraction formula, which makes up the shortage of the diffraction efficiency calculated only in the main section. Finally, the diffraction efficiency curves varied with wavelength is simulated by Matlab software, and the variation laws of the diffraction efficiency are compared for different production methods and application parameters, which provides a valuable reference for the design and production of the concave gratings.

[Preparation by spin-coating technology and characterization of UV-enhanced Lumogen film].

As an effective way to increase the UV response for CCD/CMOS, the advantage of the Lumogen film is the simple process and low cost. In the present paper the Lumogen film was deposited onto fused silica slides by the spin-coating way, which has less damage than PVD physical vacuum deposition) way. The main test and analysis of the thin-film include transmission spectrum, absorption spectrum, and excitation and emission spectrum. It was showed that these coatings were transmitted well in visible region (lambda > 400 nm), and emitted a yellowish green glow centered at -525 nm together with a wide excitation spectrum range from 200 to 400 nm. The synthesis shows that Lumogen coatings match accurately with the detected spectrum of conventional silicon-based image sensors, which makes this kind of thin films an ultraviolet responsive coating for sensors.

[Preparation and spectral characterization of Lumogen coatings for UV-responsive CCD image sensors].

Traditional charge-coupled devices (usually front-illuminated CCDs) and complementary metal oxide semiconductor (CMOS) have lower response in ultraviolet region particularly. The reason is that polysilicon gate material absorbs the ultraviolet radiation highly, which leads to a barricade of the radiation penetrating the gate to the channel of CCD. To enhance the detective responsibility of CCD in the ultraviolet region, a feasible method is to coat the surface of CCD polysilicon gate with a thin film. The thin film should have the ability of converting the ultraviolet to visible in order to enable the UV radiation to "penetrate" the polysilicon gate. An organic coating to convert the UV radiation to visible has been developed in the present paper. Lumogen thin films were deposited on fused silica substrates by vacuum evaporation of an organic dye called Lumogen Yellow S0790. Analysis of organic functional groups was used to study the luminescence mechanism of Lumogen. The optical constants of coatings were calculated by spectroscopic ellipsometry. The results indicate that Lumogen exhibits photoluminescence continuously owing to four kinds of double bonds in each Lumogen molecule. The refractive index of Lumogen film was approximately 1.3, which indicates that this film could be considered an antireflection coating. Finally, the spectral properties of Lumogen coatings were characterized by transmission, absorption, photoluminescence emission, and excitation spectra. It is showed that these coatings were transmitted well in visible region (lambda > 470 nm), and emitted a yellowish green glow centered at approximately 523 nm together with a wide excitation spectrum field from 240 nm to 490 nm. The synthesis shows that Lumogen coatings match accurately with the detected spectrum of conventional silicon-based image sensors, which makes this kind of thin films an ultraviolet responsive coating for sensors.

[Investigation of multi-wavelength effect during the measurement of UV-enhanced film's emission spectrum].

The UV-responsive detector is a dual-use device for civilian and military after the laser and IR-responsive sensors. Typical image sensor coated with a layer of down-convert frequency thin film on it's photosurface to enhance UV response is the key technology of enhancing UV-response. The UV-enhanced thin film was made in the experimental laboratory using the Zn2SiO4:Mn phosphor by spin coating method. Two peaks at 520 and 560 nm respectively in the emission spectrum of the UV-enhanced film were found by SP1702 spectrograph when the excitation wavelength was 260 and 280 nm. The peaks were found in the process of experiment of measuring and counting the quantum efficiency of UV-enhanced thin film. But the light peaks at 520 and 560 nm are not the emission light peaks by the exciting light of 260 and 280 nm. The reason why the light at 520 and 560 nm is not the emission light was analyzed based on the measurement principle of grating spectrograph. The reasons for the multi-wavelength of light overlaps during the measurement of emission spectrum were also discussed. And the equipment used to separate the overlapped different wavelengths was designed, which will be used to resolve the problem of the overlap of multi-wavelength.

Preparation of high laser induced damage threshold antireflection film using interrupted ion assisted deposition.

Single layers and antireflection films were deposited by electron beam evaporation, ion assisted deposition and interrupted ion assisted deposition, respectively. Antireflection film of quite high laser damage threshold (18J/cm2) deposited by interrupted ion assisted deposition were got. The electric field distribution, weak absorption, and residual stress of films and their relations to damage threshold were investigated. It was shown that the laser induced damage threshold of film was the result of competition of disadvantages and advantages, and interrupted ion assisted deposition was one of the valuable methods for preparing high laser induced damage threshold films.