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Transcranial magneto-acoustic electrical stimulation (TMAES) is a novel method of brain nerve regulation and research, which uses induction current generated by the coupling of ultrasound and magnetic field to regulate neural electrical activity in different brain regions. As the second special envoy of nerve signal, calcium plays a key role in nerve signal transmission. In order to investigate the effect of TMAES on prefrontal cortex electrical activity, 15 mice were divided into control group, ultrasound stimulation (TUS) group and TMAES group. The TMAES group received 2.6 W/cm 2 and 0.3 T of magnetic induction intensity, the TUS group received only ultrasound stimulation, and the control group received no ultrasound and magnetic field for one week. The calcium ion concentration in the prefrontal cortex of mice was recorded in real time by optical fiber photometric detection technology. The new object recognition experiment was conducted to compare the behavioral differences and the time-frequency distribution of calcium signal in each group. The results showed that the mean value of calcium transient signal in the TMAES group was (4.84 ± 0.11)% within 10 s after the stimulation, which was higher than that in the TUS group (4.40 ± 0.10)% and the control group (4.22 ± 0.08)%, and the waveform of calcium transient signal was slower, suggesting that calcium metabolism was faster. The main energy band of the TMAES group was 0-20 Hz, that of the TUS group was 0-12 Hz and that of the control group was 0-8 Hz. The cognitive index was 0.71 in the TMAES group, 0.63 in the TUS group, and 0.58 in the control group, indicating that both ultrasonic and magneto-acoustic stimulation could improve the cognitive ability of mice, but the effect of the TMAES group was better than that of the TUS group. These results suggest that TMAES can change the calcium homeostasis of prefrontal cortex nerve clusters, regulate the discharge activity of prefrontal nerve clusters, and promote cognitive function. The results of this study provide data support and reference for further exploration of the deep neural mechanism of TMAES.
Subject(s)
Animals , Mice , Acoustics , Brain , Calcium , Electric Stimulation , Prefrontal Cortex , Transcranial Direct Current Stimulation , Transcranial Magnetic StimulationABSTRACT
Objective To explore the results, feasibility and existing problems of semi-quantitative and quantitative risk assessment models in the assessment of chemical hazard exposure in optical fiber manufacturing enterprises. Methods The chemical hazard factors of an optical fiber enterprise in Wuhan were investigated, detected and evaluated, and the semi-quantitative and quantitative risk assessment models of occupational health of chemical hazard factors in the workplace were used for risk assessment. Results In the semi-quantitative risk assessment model, the consistency between the contact index method and the comprehensive index method was good (Kappa=0.820, P2=0.539，P<0.05), and the results were grade 1, 2, 3 and 5. The non-carcinogenic risk hazard quotient of the quantitative risk assessment model was not consistent with the three semi-quantitative methods (Kappa=0), and the results were grade 1, 2, 3, 4 and 5. Conclusion The semi-quantitative risk assessment model is more suitable for the risk assessment of the optical fiber industry than the quantitative risk assessment model.
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La gutapercha es químicamente un polímero a base de isopreno, impermeable, no poroso y radiopaco entre otras características, empleado desde el siglo XIX; sin embargo manifiesta algunos inconvenientes propios del material, lo cual ha dado lugar al nacimiento de otros materiales para mejorar sus propiedades. Recientemente se ha desarrollado y caracterizado un material novedoso a base de fibra óptica recubierta por nano partículas de plata (FONP), propuesto como un material alternativo para la obturación de conductos radiculares. En el presente estudio se seleccionaron 24 dientes para conformar cuatro grupos experimentales comparativos entre la obturación con fibra óptica y con gutapercha, ambos con el sellador AH Plus. Las raíces fueron obturadas en grupos de diez y almacenadas en solución salina a 37 oC. La filtración apical se midió desde el extremo apical de la interfaz del material hasta la extensión más coronal del tinte observado microscópicamente. Se empleó la herramienta de LAS EZ V3.0 (Leica Microsystems, Switzerland), los datos se tabularon y se analizaron. Resultados: Las mediciones de microfiltración a nivel apical e intraconductos manifestaron diferencias en favor de la gutapercha, donde los grupos experimentales manifestaron una filtración promedio correspondiente a 0.872 mm en el grupo de Gutapercha/AH-PLUS y de 2.390 mm con técnica lateral utilizando FONP/AH-PLUS, aun así se evidenció que las propiedades de sellado de la fibra óptica con nanopartículas fueron suficientes para considerarlo como un material de obturación de conductos radiculares dentales como posible sustituto de la gutapercha (AU)
Gutta-percha is chemically an Isoprene-based polymer, impervious, non-porous and radiopaque, among other characteristics, used since the 19th century, it manifests some disadvantages inherent to the material, which has led to the birth of new materials with improved properties. Recently, a novel material based on optical fiber covered by silver nanoparticles (FONP) has been developed, characterized and proposed as an alternative material for root canal obturation. In the present study, 24 teeth were selected and divided into four comparative experimental groups for obturation with fiber optics and gutta-percha, both with the AH Plus sealer. The roots were sealed in groups of ten and stored in saline at 37 oC. Apical filtration test was performed from the apical end of the material interface to the most coronal extension of the dye observed microscopically. The LAS EZ V3.0 tool was used to make the measurements and the data was tabulated and analyzed. Results: Measurements of microfiltration at the apical and intracanal level showed differences in favor of gutta-percha, where the experimental groups showed an average filtration of 0.872 mm in the Gutapercha/AH-PLUS group and 2.390 mm using FONP/AH-PLUS, even so, it was evidenced that the sealing properties of the optical fiber with nanoparticles are sufficient to consider this material as a proper filling material for dental root canals as a substitute for gutta-percha (AU)
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Root Canal Filling Materials , Optical Fibers , Gutta-Percha , In Vitro Techniques , Pilot Projects , Silver Compounds , Dental Leakage , Metal NanoparticlesABSTRACT
@#AIM: To observe the clinical effects of minimally invasive scleral buckling combined with 25G cannula intra-optical fiber lighting in the treatment of rhegmatogenous retinal detachment with the help of non-contact wide angle lens.<p>METHODS: We retrospectively analyzed 43 patients with rhegmatogenous retinal detachment from May 2011 to March 2015 in our hospital. The retinal tear locations of these patients analyzed preoperatively by pre-set lens and three-mirror contact-lens were uncertain. We detected the retinal tears intraoperatively by non-contact wide angle lens with the help of 25G cannula intra-optical fiber lighting. The tears were sealed by minimally invasive scleral buckling. The patients were followed up at 1wk, 1mo, 3mo and 6mo postoperatively. The vison and intraocular pressure were recorded with the same equipment and methods as preoperatively did. The retina reattachment and tear sealing status were also observed.<p>RESULTS: The retina were reattached by one operation in 41 patients and the reattachment rate was 95.3%. One patient suffered from incomplete retina reattachment, effusion under the retina, poor position of compressed retinal area, and succeeded by minimally invasive scleral buckling once again. One patient developed new retina tear and completely reattached by vitrectomy.<p>CONCLUSION:For those patients with uncertain retinal detachment preoperatively, minimally invasive scleral buckling combined with 25G cannula intra-optical fiber lighting could increase the success rate. The statistical analysis in large samples and the long-term complications should be further investigated.
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Fiber photometry is a sensitive and easy way to detect changes in fluorescent signals. The combination of fiber photometry with various fluorescent biomarkers has substantially advanced neuroscience research over the last decade. Despite the wide use of fiber photometry in biomedical fields, the lack of a detailed and comprehensive protocol has limited progress and sometimes complicated the interpretation of data. Here, we describe detailed procedures of fiber photometry for the long-term monitoring of neuronal activity in freely-behaving animals, including surgery, apparatus setup, data collection, and analysis.
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Animals , Female , Male , Mice , Brain , Metabolism , Calcium Signaling , Neurons , Metabolism , Neurosurgical Procedures , Optical Fibers , Optical Imaging , Methods , Photometry , MethodsABSTRACT
The method of optogenetics is a new light-control ccll technology which has developed rapidly in the field of neuro- science in the past decade. This technique is also called "a new technology destined to win the Nobel Prize in the 21st century". The bioengineering technology integrates many disciplines of optics, genetics, computer science, genetic engineering, cell biology, clectrophysiology and more. This new multi-disciplinary cross-disciplinary new technology has greatly promoted the development of neuroscience, extending to animal behavior, clinical medicine, molecular biology, cell biology and many other fields. Animal behavior research is about the study of the function, mechanism, development and evolution of animal behavior, which plays an important role in the development of neuro- science. This article describes the specific process and characteristics of optogenetics, and its application in animal behavior research, aiming at a brief review of the latest research progress in optogenetics technology.
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Abstract Introduction Polymer optical fibers (POF) are lightweight, present high elastic strain limits, fracture toughness, flexibility in bend, and are not influenced by electromagnetic fields. These characteristics enable the application of POF as curvature sensor and can overcome the limitations of the conventional technologies, especially for wearable and soft robotics devices. Nevertheless, POF based curvature sensors can suffer from environmental and light source power deviations. This paper presents a compensation technique for the environmental and light source power deviations in a POF curvature sensor. Methods The curvature sensor was submitted to variations of temperature, humidity and light source power to characterize the sensor response and evaluate the proposed compensation technique. In addition, tests with the simultaneous variation of the angle and light source power variation were performed. Results Results show that temperature and humidity effects do not lead to significative errors on the sensor measurement for wearable devices application, where a hardware-based compact and portable compensation technique of the light source deviation is applied. Moreover, the sensor with the compensation technique developed is compared with a potentiometer for dynamic measurements and the root-mean-square error of about 1° is obtained, which is lower than sensors based on similar operation principle presented in the literature and some commercially available devices. Conclusions The compensation technique proposed was able to compensate power deviations applied and resulted in a sensor with low errors with the additional advantages of compactness and low-cost, which enable its application as wearable sensors and on the instrumentation of wearable robots.
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Objective To evaluate the efficacy and safety of endoscopy-assisted percutaneous interventional procedure with a 980-nm laser for the treatment of venous malformations.Methods A total of 167 patients with venous malformation were enrolled,including 102 females and 65 males,whose age ranged from 0.5 to 60 years.Skin lesions occurred on the limbs in 66 patients,on the head and face in 48,on the chest and abdomen in 24,on the back in 13,on the neck in 10,as well as on the scrotum in 6.A 980-nm laser operated at pulse width of 0 ms-2.5 s and pulse energy of 0-20 W with a 400 μm-diameter optical fiber.Puncture was performed after circular infiltration anesthesia around skin lesions,and then the optical fiber was inserted at the same puncture point to directly or indirectly destruct the vascular wall by photothermal effects and thermal coagulation.For deep lesions around important anatomical structures,the interventional therapy was performed with the assistance of endoscopy or ultrasound.According to the size and shape of tumors,these tumors were irradiated back and forth with speeds of 2 cm/s-4 cm/s.The optical fiber was also inserted in different directions in a fan-shaped pattern for 3-5 sessions until tumors were shrunken or even disappeared.The time interval between two treatments was 3 months,and all the patients were followed up for 4 months on average.Results Of the 167 patients,148 (88.6％)were cured,11 (6.6％) markedly improved,4(2.4％) improved,and 4(2.4％) unimproved.The response rate was 97.6％.Totally,159 patients were satisfied with the therapeutic effects after 1 session of treatment,and 8 were improved after 2 sessions of treatment with a time interval of 3 months.In addition,mild postoperative pigmentation occurred in 6 (3.6％) cases,and skin burns in 3 (1.8％) cases.After 3 months,the above symptoms were improved significantly.Two (1.2％) patients had vascular recanalization and residual lesions,but they were improved after reoperation.No adverse reactions were observed,such as bleeding,scar,tendon and nerve injuries,and dysfunction.Conclusion A 980-nm laser percutaneously delivered through an optical fiber is safe and effective for the treatment of venous malformation.
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Based on the plasmon coupling effect in gold nanoparticles core-satellite nanostructures linked by thymine(T)-rich DNA hybridization and the specific Hg2+-mediated T-Hg2+-T base pair, a novel localized surface plasmon resonance (LSPR) optical fiber sensor was proposed and developed for Hg2+ detection in water.The Hg2+-induced conformational change in T-rich DNA sequence inhibited the DNA hybridization reaction, weakened the plasmon coupling effect and leaded to the change of LSPR resonance wavelength.The concentration of Hg2+ was quantitatively determined by the resonance wavelength redshift.The linear range of Hg2+ detection was about 5-150 nmol/L with LOD about 3.4 nmol/L.The specificity of the sensor was proved great by evaluating the response to other heavy metal ions such as Zn2+, Mg2+, Pb2+ and so on.This sensor was applied in environmental water detection by standard addition method,with the RSD less than 4.8% and recoveries of 94.2%-105.4%.
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Proteins presence and differences of the expression level can clarify the physiological or pathological changes in organisms;so the quantitative detection of proteins is vital for disease mechanism research;diagnosis and prognosis evaluation.Traditional protein quantitation methods at the tissue level reflected the average protein expression in cells;but ignore the differences between individual cells.In contrast;approaches for quantitative detection at single-cell level can better reflect the differences.Recently;a number of approaches for such detec-tion have been proposed;including microfluidics;microwell-based technology;optical fiber nanobiosensor;activity-based probe technology and mass spectrometry.The principles;advantages and drawbacks of these approaches are briefly introduced in this review.
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Objective To establish a stable and simple method of tracheal intubation in rodents and to establish various models that needs of endotracheal intubation .Method Sixty Kunming mice anesthetized by midazlam and ketamin, were intubated by 22 GA arterial puncture needle casing with optical fiber .Then connect the casing and ventilator and make sure the casing has been into the trachea .Result 60 mice were all successfully intubated by casing with optical fiber with no throat mucosa bleeding, edema.Glottis and trachea don’t present complications such as tracheal stenosis 7d later.Conclusion Fiber mediated intubation is a simple and useful method .It has a success rate with low incidence of complications .
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Objective:To develop a UV optical fiber in situ process monitoring method for the dissolution behavior of five cepha-lexin solid dosage forms and compare the drug dissolution behavior of different cephalexin preparations. Methods: The dissolution of five different cephalexin preparations was on-line monitored according to the dissolution method for cephalexin tablets in Chinese Phar-macopeia (2010 edition) combined with a six channel optical fiber chemical sensor in situ dissolution monitor. Results:The dissolu-tion curves could show the drug release characteristics of different cephalexin preparations, and the five different preparations exhibited various drug release features. Conclusion:An in-situ, real time, on-line and process analysis of dissolution can be obtained by optical fiber dissolution test system automatically. The release characteristics of different preparations can be presented through dissolution curves directly, which can provide reference for the overall assessment of drug internal quality and clinical medication.
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In this study, we have fabricated a fiber-optic dosimeter for a proton beam therapy dosimetry. We have measured scintillating lights with the various kinds of organic scintillators and selected the BCF-12 as a sensor-tip material due to its highest light output and peak/plateau ratio. To determine the optimum diameter of BCF-12, we have measured scintillating lights according to the energy losses of proton beams in a water phantom. Also, we determined the adequate length of organic scintillator by measuring scintillating lights according to the incident angles of proton beam. Using an optimized fiber-optic dosimeter, we have measured scintillating lights according to the dose rates and monitor units of proton accelerator.
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Light , Optical Fibers , Organothiophosphorus Compounds , Proton Therapy , Protons , WaterABSTRACT
In this study, we have fabricated a one-dimensional fiber-optic dosimeter for electron beam therapy dosimetry. Each fiber-optic dosimeter has an organic scintillator with a plastic optical fiber and it is embedded and arrayed in the plastic phantom to measure one-dimensional high energy electron beam profile of clinical linear accelerator. The scintillating lights generated from each sensor probe are guided by plastic optical fibers to the multi-channel photodiode amplifier system. We have measured one-dimensional electron beam profiles in a PMMA phantom according to different field sizes and energies of electron beam. Also, the isodose and three-dimensional percent depth dose curves in a PMMA phantom are obtained using a one-dimensional fiber-optic dosimeter with different electron beam energies.
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Electrons , Light , Optical Fibers , Particle Accelerators , Plastics , Polymethyl MethacrylateABSTRACT
Objective Focusing on the problem such as slow scanning speed, complex system design and low light efficiency, a new parallel confocal 3D profile detecting method based on optical fiber technology, which realizes whole-field confocal detecting, is proposed. Methods The optical fiber plate generates an 2D point light source array, which splits one light beam into N2 subbeams and act the role of pinholes as point source and point detecting to filter the stray light and reflect light. By introducing the construction and working principle of the multi-beam 3D detecting system, the feasibility is investigated. Results Experiment result indicates that the optical fiber technology is applicable in rotation. The measuring parameters that influence the detecting can easily be adapted to satisfy different requirments of measurement. Compared with the conventional confocal method, the parallel confocal detecting system using optical fiber plate is simple in the mechanism, the measuring field is larger and the speed is faster.
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Objective To design a new type of fluorescence detection optical system for dedicated neonatal PKU screening. Methods The system selects super-luminance UVLED for excitation light source, uses different diameter quartz fiber and Y -type optical fiber which consists of glass fiber bundles, and self focusing optical fiber for collimating light and photomultiplier tubes for testing. Results The system has many features, such as simple structure, small size and high sensitivity. Conclusion The clinic screening requirements are met by the system and a new means of rapid detection is provided for PKU screening in large quantities.