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Background：Lumbar disc herniation (LDH) is a common and frequent disease in orthopedics. It is caused by degenerative changes of the lumbar spine and compression of the lumbar nerves, with the main clinical manifestation being painful involvement of the lumbar region and the legs，which in severe cases affects the patient's quality of life. The disease is treated in a variety of ways with varying degrees of efficacy, LDH is mainly treated conservatively with oral medication or external therapy of Traditional Chinese medicine (TCM) for mild cases, while surgery is required for severe cases. LDH surgical treatment is effective, but there are still some patients whose symptoms are difficult to improve after surgery and who are not suitable for surgical treatment. Pestle needle therapy is a unique external therapy of TCM method, which is non-invasive, non-painful, not easily infected, easy to operate, and easy for patients to accept. This study aimed to design a randomized controlled trial (RCT) to explore the effectiveness and safety of pestle needle in the treatment of LDH. Methods：Sixty patients will be enrolled and randomly divided into one of two groups: the pestle needle group and the celecoxib group. The pestle needle group will be treated with pestle needle at Yaoyangguan bazhen, Heche-mingqiang section, BL23, BL25, GB30, BL40, BL57, BL60 for 30 minutes. 5 days is a course of treatment, with an interval of 2 days between courses, a total of 3 courses of treatment. The pestle needle manipulation is performed to the extent that the skin is flushed during the treatment. The celecoxib group participants will take one celecoxib capsule once a day for the duration of the study period. The Japanese Orthopaedic Association Back Pain Evaluation Questionnaire (JOABPEQ) score, Visual Analog Scale（VAS）score and Oswestry Disability Index（ODI）score were used as treatment outcome assessment indicators, while adverse events (AEs) were recorded. Patients were evaluated for efficacy at baseline, at the end of each course of treatment. Discussion: This study will determine whether pestle needle is more effective and safer than celecoxib in the treatment of patients with LDH. Trial registration The trial has been registered with the Chinese Clinical Trial Register (ChiCTR) under the Registration March ChiCTR2200057684.

Background This systematic review aims to evaluate the effectiveness and safety of silver acupuncture in treatment of myofascitis. Methods Electronic databases of all silver acupuncture for myofascitis will be searched at PubMed, Cochrane Library, Springer, Embase, China National Knowledge Infrastructure, Wanfang, and Chinese Biological Medical disc from inception to March 31, 2020, with language restricted in Chinese and English. The primary outcome is visual analog scale, a short pain scale with sensitivity and comparability. Secondary outcomes included Clinical Assessment Scale for Cervical Spondylosis, Japanese Orthopaedic Association Scores, Oswestry dysfunction index, American Orthopaedic Foot and Ankle Society-Ankle Hindfoot scale, Foot and Ankle Ability Measure, The Cumberland ankle instability tool, Pittsburgh sleep quality index, self-rating anxiety scale, self-depression rating scale, and follow-up relapse rate. The systematic review and searches for randomized controlled trials of this therapy for myofascitis. The Cochrane RevMan V5.3 bias assessment tool is implemented to assess bias risk, data integration risk, meta-analysis risk, and subgroup analysis risk (if conditions are met). Mean difference, standard mean deviation, and binary data will be used to represent continuous results. Results This study will provide a comprehensive review and evaluation of the available evidence for the treatment of myofascitis with this therapy. Conclusion This study will provide new evidence to evaluate the effectiveness and side effects of silver acupuncture for myofascitis. Due to the data are not personalized, no formal ethical approval is required. Ethics and dissemination There is no requirement of ethical approval and it will be in print or disseminated by electronic copies. Prospero registration number CRD42020151476.

Background: Chronic low back pain (CLBP) is a clinically common and recurrent disease. However, many trials have shown that auriculotherapy (AT) can effectively treat CLBP. There are currently no systematic reviews of this therapy. The plan aims to evaluate the effectiveness and safety of this treatment in patients with CLBP. Methods: This systematic evaluation will entail an electronic and manual search of all AT for CLBP from inception to January 31, 2020, regardless of the publication status or language. Databases include PubMed, Excerpt Medica Database, Springer, Web of Science, the Cochrane Library, the World Health Organization International Clinical Trial Registration Platform, the Chinese Medicine Database, the China National Knowledge Infrastructure, the Chinese Biomedical Literature Database, the China Science Journal Database, and the Wanfang Database. Other sources of information, including bibliographies and meeting minutes for identified publications, will also be searched. A manual search for grey literature, including unpublished conference articles will be performed. Additionally, any clinical randomized controlled trials related to AT for CLBP, regardless of the publication status and language limitations, will be included in the study. Study selection, data extraction, and research quality assessments will be conducted independently by 2 researchers. The main result was the use of a visual analog scale, a short pain scale, or other effective scale. Secondary outcomes included effectiveness, Oswestry dysfunction index, self-rating anxiety scale, self-depression rating scale, Pittsburgh sleep quality index, follow-up relapse rate, and adverse events. The system searches for randomized controlled trials of this therapy for CLBP. Implement the Cochrane RevMan V5.3 bias assessment tool to assess bias risk, data integration risk, meta-analysis risk, and subgroup analysis risk (if conditions are met). Mean difference, standard mean deviation, and binary data will be used to represent continuous results. Results: This study will provide a comprehensive review and evaluation of the available evidence for the treatment of CLBP using this therapy. Conclusion: This study will provide new evidence to evaluate the effectiveness and side effects of AT on CLBP. Because the data is not personalized, no formal ethical approval is required. PROSPERO registration number: CRD42020151584.

Background This systematic review aims to evaluate the effectiveness of electroacupuncture in treatment of lumbar disc herniation (LDH). Methods Electronic databases of all electroacupuncture for LDH will be searched at PubMed, Cochrane Library, Springer, EMBASE, China National Knowledge Infrastructure (CNKI), Wan-Fang, and Chinese Biological Medical disc, (CBM) from inception to February 29, 2020, with language restricted in Chinese and English. The primary outcome is Japanese Orthopedic Association Scores, a quantification scale for a comprehensive assessment according to patients' subjects feeling and objective function. Secondary outcomes included visual analogue scale (VAS), Oswestry dysfunction index (ODI), Pittsburgh sleep quality index (PSQI), Self-rating anxiety scale (SAS), self-depression rating scale (SDS), follow-up relapse rate. The systematic review and searches for randomized controlled trials of this therapy for LDH. The Cochrane RevMan V5.3 bias assessment tool is implemented to assess bias risk, data integration risk, meta-analysis risk, and subgroup analysis risk (if conditions are met). Mean difference (MD), standard mean deviation (SMD) and binary data will be used to represent continuous results. Results This study will provide a comprehensive review and evaluation of the available evidence for the treatment of LDH with this therapy. Conclusion This study will provide new evidence to evaluate the effectiveness and side effects of electroacupuncture for LDH. Due to the data is not personalized, no formal ethical approval is required.

We have studied the stress-induced martensitic transformation behaviors and the associated elastocaloric effect (eCE) for non-textured polycrystalline all-d-metal Heusler alloys of Ni50Mn32Ti18 and Ni35Co15Mn35Ti15 by a combination of Digital Image Correlation (DIC) and Infrared (IR) thermography techniques. A large but irreversible adiabatic temperature change (ΔTad) of 10.7 K at a strain level of 3.9% is observed for Ni50Mn32Ti18, whereas Ni35Co15Mn35Ti15 exhibits a reversible eCE with ΔTad = 9.0 K at a strain level of 4.6%. At lower strain levels ( 3.2%), Ni50Mn32Ti18 is plastically deformed with small strain variation in space from the DIC map. In contrast, Ni35Co15Mn35Ti15 can be deformed superelastically accompanied by large strain variation in space, which can be ascribed predominately to the crystalline orientation dependence of both the transformation strain and the Young's modulus from different orientated grains under mechanical loading. The improved reversibility of eCE for Ni35Co15Mn35Ti15 is supposed to be associated with the enhancement of d-d hybridization by the introduction of the element Co.

A high-efficiency high-power diode-side-pumped quasi-continuous wave (QCW) Nd:YAG ceramic slab laser using zigzag optical path was demonstrated. With an integrating sphere technique, the scattering and absorption coefficient of the ceramic slab were measured to be 0.0024 and 0.0016 cm−1 at 1,064 nm, respectively. Under a pump power of 6.69 kW, an average output power of 2.44 kW at 1,064 nm with a repetition rate of 400 Hz was achieved, corresponding to an optical-to-optical efficiency of 36.5 %. As far as we know, this is the highest conversion efficiency reported for QCW side-pumped single slab Nd:YAG ceramic laser.

Transparent Tm,Ho:YAG ceramic with excellent optical properties was fabricated by solid-state reaction method using high-purity commercial powders as raw materials. Optical absorption and 2.0 μm emission spectra of the ceramic specimen have been studied. The strongest emission corresponds to 5I7 → 5I8 transition of Ho3+ centered at 2.06 μm. As a result, Tm,Ho:YAG ceramic shows potential application in 2.0 μm laser devices.

The scattering is the critical loss mechanism in transparent laser ceramic materials. We present a method to determine the scattering coefficient and absorption coefficient of laser material based on an integrating sphere technique. Here, the neodymium ceramic Nd:YAG samples with Nd3+ ions doping concentration of 1.0 at% are used. For a comparison, a Nd:YAG single crystal with identical concentration is also employed. The measured scattering coefficient and absorption coefficient at 1064 nm for high quality ceramic Nd:YAG were 0.004 cm−1 and 0.001 cm−1, which were very close to that of single crystal. The optical uniformity and wave-front distortion properties were also investigated by means of a Hartmann wavefront analyzer. The following laser performance tests demonstrate a maximum output power of 425 W in a short plano–plano configuration for the high quality Nd:YAG ceramic, which was nearly same with that of single crystal.

We report a high-power, narrow linewidth and tunable quasi-continuous-wave (QCW) yellow laser system at 589.159 nm. The system is of a design employing single-pass sum-frequency generation (SFG) in a LBO crystal by mixing the 1064 nm with 1319 nm lines from a two diode-side-pumped Nd:YAG master oscillator-power amplifier (MOPA) laser system. With the pump power of 35 W at 1064 nm and 25 W at 1319 nm, a 7.5 W QCW output of the SFG yellow laser at 589.159 nm, which is the vacuum wavelength of a general sodium D2 line, is obtained with a linewidth less than 0.7 GHz and a beam-quality factor M 2=1.2. The wavelength of the laser can be precisely step-tuned from 589.148 to 589.167 nm with an increment of 0.13 pm by means of a temperature-controlled etalon.

This letter reports a new class of nonlinear optical (NLO) chromophores, of which 2-dicyanomethylen-3-cyano-4-{2-[2-(4-( N , N -di(2-hydroxyethyl)-amino)phenylazo)-thien-5]- E -vinyl}-5,5-dimethyl-2,5-dihydrofuran ( 2a ) is the prototype with high thermal stability and large optical nonlinearity. Chromophore 2a was synthesized based on the azothiophene conjugated spacer and TCF electron-withdrawing acceptor, and characterized by IR, UV–Vis, MS and NMR spectra. A high decomposition temperature of 244 °C was determined by TGA measurement, and a first hyperpolarizability (zero-frequency hyperpolarizability, β 0 ) as large as 800 × 10 − 30 esu was estimated by HRS technology.

Two series of novel diazo chromophores with tricyanofuran as acceptors and 3,4-disubstituted thiophene as bridges were prepared for second-order nonlinear optical applications. The chromophores were fully characterized using FT-IR, UV–vis, NMR and MS; thermal gravimetric analysis and differential scanning calorimetry revealed that the diazo-based chromophores have excellent thermal stability. The electrooptic coefficients ( γ 33 ) were measured in the chromophores-doped poly(Bisphenol A Carbonate) films at the fundamental wavelength of 1315 nm, and the highest γ 33 achieved was 30 pm/V.

This paper reports a novel nonlinear optical polymer BP-AVT-TCV functionalized with a thiophene- and tricyanovinyl-substituted chromophore. BP-AVT-TCV was synthesized by the post-tricyanovinylation of an epoxy-based precursor polymer BP-AVT, and had a high molar functionalization degree of chromophore (70 mol.%). It had an enhanced glass transition temperature (Tg = 164 °C) compared with BP-AVT (Tg = 114 °C), and a high decomposition temperature (Td,5% = 295 °C). BP-AVT-TCV was further cross-linked to achieve the three-dimensional (3D) network of thermosetting polyurethane (PU). The poled PU films revealed an electro-optic (EO) coefficient (γ33) value of 21 pm/V at a wavelength of 1315 nm. The structures of the polymers were confirmed by FT-IR, UV–Vis, and 1H NMR spectra.

The fabrication and characteristics of a new type of polymeric electro-optic modulator with double channels in attenuated total reflection (ATR) configuration, made of a thermally crosslinkable polyurethane, has been demonstrated in this paper. The fabrication procedure of proposed double-channel ATR modulator is extremely simple, it can be implemented by replacing a single electrode with two discrete electrodes in a single channel ATR modulator. Independent operation of both channels is demonstrated at a modulation speed of 500 MHz. The total measured insertion loss of the modulator is below 1.5 dB. There are no measurable cross talks due to the large horizontal separation of two channels and the small vertical separation of the electrode pair. A long-term thermal stability of the fabrication modulator at an elevated temperature, 100 °C, is obtained due to crosslinking polyurethane as the waveguide layer of the devices.

A device-quality second-order nonlinear optical (NLO) polymer prepared by post-functionalization of an epoxy-based precursor polymer exhibits an improved processability, such as good solubility in common organic solvents and excellent film-forming property. Toluene-2,4-diisocyanate as a cross-linking agent was used to cross-link the NLO polymer to create a three-dimensional (3D) network of polyurethane during poling. Using this thermosetting polyurethane, an electro-optic (EO) modulator based on attenuated-total-reflection (ATR) technology was fabricated successfully, and its performance was discussed. The highest EO coefficient of 16 pm/V for this modulator measured at a wavelength of 832 nm was obtained by an improved ATR method, and a high temporal stability of the poling-induced order was observed at elevated temperature up to 100 °C.

Magnesium ethoxide was used for the first time in the synthesis of the titled compounds. In these preparations, product yields were significantly improved compared with similar synthesis catalyzed by other metal ethoxides. The effectiveness of magnesium ethoxide as catalyst was tentatively rationalized.

Polymeric optical waveguides based on a new synthesized bisphenol A–aldehyde polymer (PA-1 resin) have been fabricated using photolithography and reactive ion etching technique. The polymer is novel with relatively high refractive index, low birefringence and absorption at the optical communication wavelengths. The single-mode channel waveguides exhibit a propagation loss of 0.41 ± 0.05 dB/cm at a wavelength of 1.31 μ m and 0.5 ± 0.05 dB/cm at 1.55 μ m for both the TE and TM polarizations. The polarization-dependent loss of the waveguides is 0.1 ± 0.05 dB/cm at these wavelengths.

Multi-channel light modulation, which is based on the attenuated total reflection (ATR) configuration, is proposed in this paper. The device consists of a prism and a polymer optical waveguide. Guided modes which give rise to the resonance dips in the ATR spectrum are employed to act as the modulation channels. Double channel's modulation with the same modulation signal has been demonstrated in the proposed device.

Prepolymers containing vanadyl phthalocyanines, prepared by the reaction of amino-substituted vanadyl phthalocyanines and diglycidyl ether of biphenol A, can be cured to give transparent network polymeric films, which show absorptions at 780 nm and 820 nm, respectively. The films are stable to organic solvents, inorganic bases and acids. Ultrafast optical responses were observed for both polymers with typical decay time of about 240 fs.

A high light-induced damage threshold attenuated-total-reflection modulator is fabricated by replacing the metal film with poly(methyl methacrylate) as coupling layer, and the optimum conditions of the device are analyzed by calculating the reflectivity of a prism-waveguide configuration. The light-induced damage thresholds as high as ∼4 W/cm 2 and ∼0.2 MW/cm 2 for CW laser and ns pulses, respectively, are obtained. The device offers potentials in wireless optical communication for long distance transmission and applications in ultrashort laser systems such as energy balance, mode-locking or Q-switching.

Novel NLO azo-based chromophores containing strong electron-withdrawing groups and benzene or thiazole moiety as conjugated bridges were synthesized and characterized. β values were measured by HRS method, they are in the range of 238–1459 × 10−30 esu at the fundamental wavelength of 800 nm. For chromopheres 3 and 4, β values at the fundamental wavelength of 1064 nm were also measured, they are 1575 × 10−30 esu and 935 × 10−30 esu, respectively. Thermal stabilities for these chromophores are reported. We also discuss the effects of different acceptors and conjugating moieties on β.

We have synthesized a polyurethane NLO polymer with 2-dicyanomethylene-3-cyano-5, 5-dimethyl-4-p-N, N-diethanol-aminostyrene-2, 5-dihydrofuran (DAS-TCF) chromophore. Micro- and macroscopic optical nonlinearities including the molecular hyperpolarizability of the chromophore and electro-optic coefficient of its polyurethane film at various wavelengths have been measured by typical optical methods (HRS and ATR techniques), and also by a modified solvatochromism method.

We suggest a three-dimensional theoretical model to explain the origin of light wave propagation in a quasiwaveguide structure formed by a thin film of refractive index smaller than the substrate. The physical principles involved are illustrated by the use of a combination of multiple-wave interference and coherent multiple scattering. Not only the theoretical details and the important analytic formulas describing the properties of wave propagation in the quasiwaveguide were given, but also the positions and linewidths of the quasiwaveguide modes, the intensity distribution in the film, the intensity of the reflected spot, and the intensity distribution of the scattered light (m lines) are studied in detail. We divide the modes in the quasiwaveguide into three kinds: cavity modes, leaky modes, and degenerate modes. Some interesting problems are discussed. We investigate the properties of wave propagation in a quasiwaveguide made with a doped polymer film and discuss the origin of scattering.

Refractive-index-modulated holographic gratings have been recorded for the first time in the interior of polymer bulk, by a femtosecond laser at 800 nm. The polymer bulk was prepared by doping an azo dye, HPNA in polymethylmethacrylate. This sample preparation process is quite simple. Multi-photon absorption and, as a result, photoinduced changes in isomer population were postulated as a brief discussion on the mechanism of the grating formation.

Using the post-azo coupling reaction in organic solvents, we synthesized two series of nonlinear optical (NLO) polyamic acids with four different NLO chromophores. The properties of these polymers were characterized and compared. We found that increasing the electron withdrawing ability or replacing the benzene ring in the π-conjugated system with thiophene will result in the red shift of the maximum absorption band and enhancement of the nonlinear optical response.

We have studied the effect of the reading beam on the decay process of the photoinduced second-order susceptibility χ(2) in both the guest-host system (disperse red 1-doped polymethyl methactrylate) and the side-chain system (disperse red 19-functionalized polyimide polymer). Both experimentally and theoretically, we have proved that the reading beam has the erasure effect on the decay process, that is, χ(2) decays faster in the high intensity than in the low intensity of the reading beam. Furthermore, the relationship between the time constant τB of the slow component of the decay process and the intensity of the reading beam I1.06 is derived from the theoretical equations, which is fitted well with the experimental results. Based on the fitting parameters, we also compare, quantitatively, the thermal-induced orientational diffusion of trans- and the quantum efficiency of trans-to-cis photoisomerization in the two systems.

The thermal optical coefficient (TOC) and volume thermal expansion coefficient (TEC or β) of poly(methyl methacrylate) (PMMA) polymers doped with azobenzene dyes were investigated. A novel approach for determining the TEC has been suggested and a non-linear variation in the TOC with increasing wt% of the dopant has been observed and tentatively explained. In addition, the refractive index (RI) contrast necessary for forming a waveguide was demonstrated to be easily achievable by adding a higher-refractive-index material to the blank polymer. Copyright © 2000 John Wiley & Sons, Ltd.

The hydroxyl groups formed during the reaction of DGEBA (diglycidyl ether of bisphenol A) and aniline are used for the first time to form crosslinkable polyurethane. The very active diisocyanate groups as a pure reagent are only introduced to the reaction system at the last step of the crosslinking reaction, which greatly improves the preparation procedure. A very good film-forming property was found and a d33 value as high as 320 pm V− was measured for the poled polymer film. Copyright © 2000 John Wiley & Sons, Ltd.

Efficient optical poling of a crosslinkable polyurethane film, in which a high crosslinking density can result, is experimentally investigated and compared with corona poling. The photoinduced orientation and the crosslinking processes of the chromophores can be performed separately. The heating rate and the final curing temperature are crucial for the optical poling procedure. Through thermal curing of the sample, the stability properties of photoinduced polar order are demonstrated to be dramatically enhanced, especially its photostability. It is also shown that corona poling is more effective than optical poling in the case of a crosslinkable thick film.

A comparison of temperature-dependent optical poling between two azopolymers, a side-chain polymer system (disperse red 19-functionalized polyimide polymer) and a guest-host polymer (dispersed red 1-doped polymethyl methacrylate), has been performed at various poling temperatures ranging from 25 to 70 °C. The observed saturation levels of induced second-order nonlinear susceptibility in all cases could be resolved into two components with a faster and a slower decay process after poling, which were respectively attributed to the cis-to-trans isomerization and the loss of induced polar order by orientational diffusion of azo chromophores. The saturation level and its slower decay component were observed to increase with the increase of poling temperature in the side-chain polymer, but to decrease in the guest-host system. The faster decay components were observed to decrease with poling temperature in both the systems. The decay times of the faster component decreased with temperature in the two polymers. ...

Employing all-optical poling technique, we propose a novel method for optical storage based on the mechanism of orientational hole burning and photoinduced molecular reorientation of azobenzene. Recording of an optical binary image was experimentally demonstrated. The recorded information can be stored for a long time and also can be erased rapidly with a circularly polarized light. Furthermore, wavelength conversion of optical image is obtainable using such method. The storage characteristics of two different polymer systems, azo-doped poly(methyl methacrylate) (PMMA) and azo-functionalized polyimide (PI), were investigated and compared.

A series of electro-optic polyimides containing azobenzene side-chain have been synthesized and characterized. The key step in the synthesis was the diazonium coupling to aniline-containing poly(amic acid) in nonaqueous solvent. The chromophore density was determined by 1HNMR spectroscopy. High chromophore density up to 100% by mole has been obtained due to the utilizing of the novel synthetic method, resulting in a large electro-optic coefficient. These polymers show high thermal stability monitored by TGA and UV/Vis measurements. The prepolymer poly(amic acid)s are soluble in many organic solvents and have good film forming property.

Synthesis of three novel crosslinked polyimides with push-pull azobenzene group has been developed. 4-Nitre4′-[N, N-bis (2-aminoethyl)]aminoazobenzene was first prepared, then poly(amic acid) prepolymer, one crosslinkable component, was obtained by aminolysis of alternating styrene-maleic anhydride copolymer, alternating thiophene-maleic anhydride copolymer or alternating benzofuran-maleic anhydride copolymer with it, and at last the crosslinked second-order nonlinear optical polyimide was synthesized by crosslinking and imidizing poly (amic acid) prepolymer with corresponding alternating copolymer. The crosslinking and imidizing processes were studied by IR and UV-Vis spectra. The chromophore density in one of the crosslinkable components, poly(amic acid) prepolymer, and the thermal stability of crosslinked polyimide thin film were measured by UV-Vis spectra.

Permanent optical poling was achieved in a crosslinkable system, a polyurethane with disperse red 19. Thermal stability of light-induced second order susceptibility was investigated for samples poled at different temperatures. The induced susceptibility d33 of the sample poled at 85°C was measured to be 46 pm/V, and could be stable at that poling temperature. Experimentally, it was demonstrated that the chemical crosslinking of the polymer matrix in optical poling procedures resulted in good stability of polar orientation of the nonlinear optical chromophores.

Picosecond optical bistable behaviors in an optical quasi-waveguide and a planar waveguide made with metallophthalocyanine-doped polymer films were demonstrated. Input–output curves with hysteresis characteristics were measured at 532 nm. In the quasi-waveguide through the observation on the bistabilities of the reflected light at various offset angles, the responsibility of high-order modes for the bistable behaviors was investigated by using the mode spectra. The non-linearity giving rise to optical bistability was predominantly electronic in origin. © 1997 Elsevier Science S.A.