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The ridge waveguide on the TGG crystal has been fabricated through the combination of the ion implantation and the femtosecond laser ablation. Firstly, optical planar waveguide was formed on the to...

The work reports on the preparation and optical characterization of 75P2O5-15B2O3-9Al2O3-Bi2O3 glass by using the melt-quenching method and absorption spectroscopy, respectively. Further, 0.4-MeV proton implantation of a fluence of 8.0 × 1016 ions/cm2 was carried out on this glassy sample and it was tested as a waveguide at a wavelength of 632.8 nm for the first time to our knowledge. The m-line curves of the waveguide were measured before and after successive annealing treatments. The formation theory of the planar waveguides is discussed through simulations of the energy loss distribution and analysis of the reconstructed refractive index profile. The results should be useful in the design and fabrication of bismuth-doped phosphate glass and its use in integrated photonics devices.

In this work, we report the fabrication of an optical waveguide by single-energy H+ ion implantation in the Er3+-doped phosphate glass. The ion implantation conditions are with energy of 0.4 MeV and a fluence of 8.0×1016 ions/cm2. The dark mode spectrum of the waveguide structure was measured by the prism coupling experiment. The refractive index change along with the penetration depth was fitted by using the reflectivity calculation method (RCM). Finally, the calculated near-field light intensity distribution shows superior waveguide properties, which demonstrates its promising potentials for compact optical integrated devices.

The optical planar waveguides were fabricated by proton implantation with an energy of 400 keV and a dose of 8 × 1016 ions / cm2 or 400-keV helium-ion implantation with a fluence of 6 × 1016 ions / cm2 in the fluoride lead silicate glass. The morphologies were studied by a Zeiss microscope to estimate the thickness of the waveguides. The annealing effects on the fluoride lead silicate glass waveguides were investigated by 60 min annealing cycles at different temperatures ranging from 260°C to 310°C in air atmosphere. The dark-mode spectra and corresponding effective refractive indices before and after the thermal treatments were measured by the prism coupling system. The Stopping and Range of Ions in Matter 2013 code was used to simulate the irradiation process and calculate the energy losses. The refractive index distributions were reconstructed by the reflectivity calculation method. The near-field light intensity profiles of the proton and helium-ion implanted fluoride lead silicate glass waveguides were measured by the end-face coupling system. The comparison of optical properties between the proton-implanted waveguide and helium-ion implanted one was carried out. The experimental results show that the helium-ion implantation is more suitable for the fabrication of the fluoride lead silicate glass optical waveguides and the He + -implanted waveguide has better optical propagation performances.

Background: Coronavirus disease 2019 (COVID-19) is a respiratory infectious disease with a high fatality rate. Up to now, there are an estimated 26 million confirmed cases and 865,000 deaths around the world. But no effective way can control this disease. As the country that first discovered and treated the COVID-19, China has formed relatively mature prevention and treatment methods such as “3 prescriptions and 3 drugs.” Xuan Fei Bai Du Fang, as a member of “3 prescriptions and 3 drugs,” has very good clinical effects Methods: The PubMed, EMBASE, ClinicalTrials.gov, Cochrane Library, China National Knowledge Infrastructure, and Wanfang databases were searched for randomized controlled studies published to date. This study only screens clinical randomized controlled trials on QFBDF for COVID-19 to evaluate its efficacy and safety. Import all literatures that meet the requirements into Endnote X9 software. The information was finally cross-checked by 2 reviewers. Papers selected for review were assessed for risk of bias according to the criteria. Quality assessment on design of study, risk of bias, indirectness and imprecision were assessed using the GRADE framework. Where sufficient studies were available, publication bias was assessed visually using funnel plots. Relative risks for primary and secondary outcomes were calculated on an intent-to-treat basis and pooled using random effects meta-analysis. the continuous is expressed by mean difference or standard mean difference, eventually the data is synthesized using a fixed effect model or a random effect model depending on whether or not heterogeneity exists. The heterogeneity of studies will be evaluated by Q-test and I2 statistic with RevMan5.3. Results: The time from a positive diagnosis to a negative result of 2 consecutive nucleic acid tests (not on the same day), cure rate. The results of our research will be published in a peer-reviewed journal. Conclusion: The purpose of this systematic review is to provide new evidence for the effectiveness and safety of Xuan Fei Bai Du Fang in the treatment of COVID-19. PROSPERO registration number: CRD42020213950.

Terbium scandium aluminum garnet crystal is a promising material which has excellent characteristics for magneto-optical devices. We report on the fabrication of optical planar and ridge waveguides in the terbium scandium aluminum garnet by using combination of helium ion implantation and precise diamond blade dicing. The conditions for the ion implantation are an energy of 400 keV and a fluence of 6 × 1016 ions/cm2. The rotating velocity and cutting speed of the diamond blade were set to be 20,000 rpm and 0.1 mm/s, respectively. The implantation depth and distributions of energy loss were calculated by the stopping and range of ions in matter 2013. The refractive index distribution and the dark-mode spectrum for the implanted planar waveguide were obtained by the reflectivity calculation method and the prism coupling system, respectively. The near-field intensity profiles of both the planar and ridge waveguides were measured by the end-face coupling technique. The optical guiding properties of the terbium scandium aluminum garnet waveguides suggest that they can serve as candidates for optical waveguide isolators.

In this work, we report on the preparation and characterization of the planar and ridge optical waveguides in the E r 3 + -doped germanate glass by combining hydrogen ion implantation and precise diamond blade dicing. The nuclear energy loss and the implantation depth were calculated by the SRIM 2013 software. The refractive index profile was obtained by the reflectivity calculation method. The dark-mode spectrum and the near-field intensity distribution were measured by the prism coupling system and end-face coupling technique, respectively. This work has important reference significance for the development of E r 3 + -doped germanate glass active devices in the optical communication field.

Planar waveguides in magneto-optical glasses (tb3+-doped aluminum borosilicate glasses) have been produced by a 550-kev proton implantation at a dose of 4.0 x 10(16) ions/cm(2) for the first time to our knowledge. after annealing at 260 degrees c for 1.0 h, the dark-mode spectra and near-field intensity distributions are measured by the prism-coupling and end-face coupling methods. the damage profile, refractive index distribution and light propagation mode of the planar waveguide are numerically calculated by srim 2010, rcm and fd-bpm, respectively. the effects of implantation on the structural and optical properties are investigated by raman and absorption spectra. it suggests that the proton-implanted tb3+-doped aluminum borosilicate glass waveguide is a good candidate for a waveguide isolator in optical fiber communication and all-optical communication. (c) 2016 elsevier ltd. all rights reserved.

Chronic vascular complications are the major causes of death and disability of type 2 diabetes mellitus (T2DM) patients. von Willebrand factor (vWF) is involved in pathogenesis of cardiovascular diseases (CVD). Previous studies showed elevated plasma levels of vWF in T2DM patients with CVD, but the association has not been validated. The aim of this meta-analysis was to compare plasma levels of vWF in T2DM patients with and without CVD. We performed a meta-analysis based on published case-control studies of vWF in T2DM patients with and without CVD indexed in PubMed and other databases updated to April 2018. After independently assessing methodological quality and extracting data, 9 eligible studies were obtained including 576 cases and 632 controls. The standard mean difference (SMD) and 95% confidence intervals (95% CI) were calculated using random-effects model. Meta-analysis showed that plasma level of vWF was significantly higher in T2DM patients with CVD than T2DM patients without CVD (SMD = 0.61; 95% CI, 0.32-0.90; P

The work reports on a concise investigation on the application of the proton implantation and the femtosecond laser ablation for the infrared two-dimensional waveguide formation in the Nd3+-doped phosphate glass. The Nd3+-doped phosphate glass was firstly irradiated by the 400-keVprotons with a fluence of 8.0 × 1016 ions/cm2 and then ablated by the femtosecond laser with 800-nm central wavelength, 1.0-kHz repetition rate and 120-fs pulse duration. The optical microscope image of the end-face was captured by an optical microscope for the implanted and ablated Nd3+-doped phosphate glass. The intervals between two neighbor grooves was 30 μm. The guiding characteristics of the 2D waveguide were measured by the end-face coupling technique. The results suggest that a 2D waveguide operating at 976 nm is fabricated in the Nd3+-doped phosphate glass. The hybrid fabrication technique opens a versatile and flexible way toward 2D photonic devices in the Nd3+-doped phosphate glass.

Ion implantation and precise diamond blade dicing are amazing tools allowing the accurate formation of waveguide structures. In this work, we report on the fabrication and assessment of a ridge waveguide in the high-gain Nd3+-doped laser glass by the 400-keV H+-ion implantation with a fluence of 8.0 × 1016 ions/cm2 and the precise diamond blade dicing at a rotating speed of 2.0 × 104 rpm. The relative atom displacement induced by the proton implantation was simulated by the SRIM 2013. The cross section of the two-dimension structure was captured by a microscope and its lateral dimensions were 3.75 μm × 10 μm. The optical confinement of the ridge waveguide was recorded by the technique of the end-face coupling and its propagation loss was about 3.9 dB/cm at 976 nm. The ridge waveguide supported mono-mode at 976 nm can serve as a photonic device.

An optical waveguide is an important dielectric device that guides the propagation of light waves. Ion implantation is a competitive waveguide preparation technique with advantages including reliance, simpleness and flexibility. In this work, a 400-keV helium ion implantation with a fluence of [Formula: see text] ions/cm2 was carried out to manufacture a planar waveguide on the surface of the fused silica glass. The formation mechanism of the waveguide was analyzed by the nuclear energy deposition based on the SRIM 2013 and the refractive index distribution with the help of the reflectivity calculation method (RCM). The geometry structure and the guiding performance of the waveguide were studied by the metallographic microscope and the end-face coupling system, respectively. The investigation on the fabrication and characteristics of fused silica glass optical waveguides is of great significance for the development of passive devices in the field of optical communications.

Gain guided and index alternate-guided (GGIA-G) fiber is suggested by our group recently. In order to grasp more laser performance of the GGIA-G fiber, the threshold characteristics of the fiber laser is analyzed in this work. Firstly, the improved rate equations of the forward pumped GGIA-G fiber laser are established and solved. Secondly, the threshold pump power of the GG-IG fiber, GG-IAG fiber and GGIA-G fiber are compared, and the effects of parameters including Nd3+ concentration N, fiber length L, fiber core radius a, refractive index difference Δn and output mirror reflectivity R2 on the threshold pump power Pth are discussed in detail, separately. Finally, the method of designing the fiber parameters for single mode laser operation is given out. When R1s=1.0, R2s =0.8, a=50 μm, N=1.0×1020 cm−3, L2: L=0.2 and Δn=-0.005, the allowed fiber length range for single mode laser operation is about 4.1 cm∼9.0 cm. The related research results will be helpful to the better application of the GGIA-G fiber.

There are many joint forms of shield tunnel lining segments. The new types of joints mainly include plug-in type and slide-in type where few researches concerning whose mechanical properties. This paper aims to construct a full-size numerical simulation model of the selected slide-in quick coupling joint and accomplish a fine prefabricated model. Given the complexity of the mechanics on the joint, loading and constraints are designed into the simulation model which achieves a successful simulation on various working conditions. The numerical results show that joint deformation can be reduced by optimizing the connectors’ position; A strengthening on the structure of C-type embedded groove can improve the overall bearing capacity of segment joint; Axial force can significantly reduce the deformation of the joint. Therefore, this research will help facilitate the effective design of the new type of shield tunnel joint.

The heterogeneous helical cladding (HHC) fiber is a new type of extreme large mode area fiber proposed by our group firstly. In this work, Nd 3 + -doped phosphate glass HHC fibers with different core radius r ( 60 μ m – 175 μ m ) and different helix pitch Λ (5.25 cm and 10.5 cm) were fabricated successfully. Firstly, the fiber preform glass was designed and prepared, and the performance of which was measured. Secondly, the HHC fiber preform was made by rod-in-tube method. Thirdly, the HHC fiber was obtained by the spiral drawing method, then the loss and gain performance of which were measured. Based on the experiment results, the following conclusions can be drawn: the larger the Λ (or r), the lower the loss coefficient L, and when r (or Λ ) is the same, the larger the Λ (or r), the higher the net gain coefficient. This work will facilitate the further exploration and application of the HHC fiber.

The k9 glass emerges as the promising host for the waveguide formation, owing to its unique optical properties. Ion implantation is a powerful technique for the fabrication of optical waveguides. In this work, the 400-keV proton implantation at a dose of [Formula: see text] [Formula: see text] was performed on the k9 glass to manufacture optical waveguide. Continuous annealing treatment at intervals of [Formula: see text] was used to enhance the guiding performances of the waveguide. The dark-mode spectrum and the refractive index profile of the waveguide were obtained by a prism coupling system and a reflectivity calculation method, respectively. The near-filed intensity distribution was measured by an end-face coupling equipment. The results suggest that the light field can be confined within the waveguide layer.

In this paper, the fabrication of optical planar waveguide in PTR glass by proton implantation is reported for the first time to our knowledge. The planar waveguide with a width of approximately 3.4 μm was generated under the condition of 400 keV H+ ion implantation with a dose of 8.0 × 1016 ions ‧ cm−2 at room temperature. The formation mechanism of PTR glass waveguide was illustrated with the aid of the SRIM program. The optical characteristics of the PTR waveguide, such as refractive index profile and near-field intensity distribution, were investigated in detail. The fabricated PTR waveguide presents a structure of both index-well and optical barrier according to the reconstructed refractive index profile. The finite-difference beam propagation method was carried out to simulate guiding modal distribution. Besides, in order to study the thermal stability of the H+-implanted PTR waveguide, annealing treatment was conducted at different temperatures.

Sm[Formula: see text]-doped bismuthate glass has been synthesized by means of the classic melt-quenching technique. Its optical properties were characterized, which included refractive index, absorption and fluorescence spectra. The measured data suggest that the Sm[Formula: see text]-doped bismuthate glass is suitable for optoelectronic applications. A Sm[Formula: see text]-doped bismuthate glass waveguide operating at 1.539 [Formula: see text]m has been manufactured by using the proton implantation with a 0.4 MeV energy and a 8.0 × 10[Formula: see text] ions⋅cm[Formula: see text] fluence for the first time to our knowledge. The effective refractive indices of the propagation modes for the glass waveguide were obtained by the m-line technique. The energy loss caused by the collision of the irradiated protons and the nuclei of the target Sm[Formula: see text]-doped bismuthate glass was calculated by the SRIM 2013. The refractive index profile and the near-field guided mode distribution for the waveguide structure were fitted through the reflectivity calculation method (RCM) and the FD-BPM method, respectively. The proton-implanted Sm[Formula: see text]-doped bismuthate glass waveguide is an alternative for an integrated device in the telecommunication band.

In this work, the high-gain Nd3+-doped laser glass was chosen as the target material, and the optical waveguide was formed on the glass by the H+ ion implantation under the conditions of a 8.0 × 1016-ions cm−2 fluence and a 0.4 MeV energy. The post-annealing at 200 °C for 1 h was applied to improve the optical quality of the waveguide. A metallographic microscope was used to detect changes in morphology caused by implanted ions in the high-gain Nd3+-doped laser glass. The characteristics of the ion-implanted high-gain Nd3+-doped laser glass optical waveguide, such as the dark-mode profiles and the near-field intensity distributions, were measured by experimental instruments including a prism coupler and an end-coupling system. The effects of nuclear energy loss of implanted ions on the refractive index variation of the substrate were analyzed by the reflectivity calculation method. The interaction mechanism of implanted protons with the high-gain Nd3+-doped laser glass was discussed by the SRIM 2013 code. It lays a theoretical and experimental basis for the development of high-gain Nd3+-doped glass waveguide lasers and amplifiers.

A successful design which used FPGA to do Positive/Zero/Negative Justification for adapting E1 (2.048Mbit/s) to SDH C-12 is presented. Gray code is adopted to realize the sampling of write pointer in reading clock domain and induct frequency doubling technology to deduct/insert reading clock, and a positioning counting device is set to complete the positioning insert of specified bytes. Asynchronous FIFO and Ping-Pong operation technique are both adopted. The design realizes stimulation, placement and routing under Quartus II 9.0 circumstances. It is a reusable hardware module which increases performance when compared to existing solutions.

Nd3+:SrAlF5 nanocrystals embedded fluorophosphate glass–ceramics were prepared by the melt quenching and subsequent thermal treatment method. The formation of SrAlF5 nanocrystals in the glass was confirmed by X-ray diffraction and scanning electron microscope. The fluorescence intensity and lifetime of the glass–ceramics increased with the increase of size of nanocrystals. Importantly, by controlling growth of nanocrystals, an obvious enhancement of lifetime (725 μs) emerged in the glass–ceramics heat-treated at 510 °C and the transmittance can reach to 72.2 % at 1049 nm. The enhanced fluorescence intensity and lifetime were ascribed to the comfortable local environment to the Nd3+ ion and scattering of the nanoparticle embedded into the glass matrix.

Tb3+-doped aluminum borosilicate glasses are important magneto-optical materials for optical isolators. Optical waveguides are basic components in integrated photonics. By using the ion implantation technique, optical guiding structures can be produced in Tb3+-doped aluminum borosilicate glasses, and miniaturized waveguide isolators can be realized. In this paper, planar waveguides have been fabricated in Tb3+-doped aluminum borosilicate glasses by (6.0 + 5.5) MeV carbon ion implantation at doses of (8.0 + 4.0) × 1013 ions/cm2. The optical properties of optical waveguides are measured by equipments of prism coupling and end-face coupling systems. They are also analyzed by simulation programs of intensity calculation method and beam propagation method. The waveguides with good optical performances suggest potential applications on fabrication of waveguide isolators in Tb3+-doped aluminum borosilicate glasses.

Rationale: In patients with pituitary thyroid hormone resistance, the ability of the pituitary gland to detect (and down-regulate) the increase of triiodothyronine is selectively impaired, while the periphery remains sensitive to triiodothyronine levels, producing symptoms of peripheral thyrotoxicity. Subsequently, there is no feedback of pituitary production of thyroid-stimulating hormone (TSH), which is responsible for this hyperthyroidism. Patient concerns: We report a case of a 46-year-old Chinese woman diagnosed with a thyroid nodule, with normal thyroid function. She underwent conventional subtotal thyroidectomy, and replacement therapy (levothyroxine) was used for as convention. However, it was later proven that she had pituitary resistance to thyroid hormone, as supra-physiological doses of levothyroxine were required to normalize TSH levels, which resulted in peripheral thyrotoxicity. Diagnoses: Based on the patient's symptoms, laboratory tests results, imaging examinations, and genetic analysis (which noted a gene mutation), a diagnosis of pituitary resistance to thyroid hormones was confirmed. Interventions: The dose of levothyroxine was adjusted periodically and β-adrenergic blocker was used as symptomatic treatment. Outcomes: The outcome in the reported case has been satisfactory despite the persistence of non-suppressed TSH. Lessons: An inappropriate level of TSH should always be evaluated. We found a new mutation (H435A) of the thyroid hormone receptor beta gene, which allowed for the establishment of a definitive diagnosis.