Read by QxMD icon Read

diode laser

Jaidip Jagtap, Gayatri Sharma, Abdul K Parchur, Venkateswara Gogineni, Carmen Bergom, Sarah White, Michael J Flister, Amit Joshi
Vascular supply is a critical component of the tumor microenvironment (TME) and is essential for tumor growth and metastasis, yet the endogenous genetic modifiers that impact vascular function in the TME are largely unknown. To identify the host TME modifiers of tumor vascular function, we combined a novel genetic mapping strategy [Consomic Xenograft Model] with near-infrared (NIR) fluorescence imaging and multiparametric analysis of pharmacokinetic modeling. To detect vascular flow, an intensified cooled camera based dynamic NIR imaging system with 785 nm laser diode based excitation was used to image the whole-body fluorescence emission of intravenously injected indocyanine green dye...
February 1, 2018: Biomedical Optics Express
Robert A Convissar
BACKGROUND: Lasers are promoted as viable adjunctive treatment methods for nonsurgical periodontal pocket reduction; however, the literature supporting this use is lacking. Multiple meta-analyses found no benefit to laser use for this procedure. The American Dental Association issued clinical practice guidelines about laser use in periodontal pockets, concluding that diode, neodymium:yttrium-aluminum-garnet, and erbium lasers have no benefit as adjunctive therapies to scaling and root planing...
March 13, 2018: Journal of the American Dental Association
Tanya Moutray, Jennifer R Evans, Noemi Lois, David J Armstrong, Tunde Peto, Augusto Azuara-Blanco
BACKGROUND: Diabetic retinopathy (DR) is a chronic progressive disease of the retinal microvasculature associated with prolonged hyperglycaemia. Proliferative DR (PDR) is a sight-threatening complication of DR and is characterised by the development of abnormal new vessels in the retina, optic nerve head or anterior segment of the eye. Argon laser photocoagulation has been the gold standard for the treatment of PDR for many years, using regimens evaluated by the Early Treatment of Diabetic Retinopathy Study (ETDRS)...
March 15, 2018: Cochrane Database of Systematic Reviews
N K Stevenson, C T A Brown, J-M Hopkins, M D Dawson, C Kränkel, A A Lagatsky
We report on the first demonstration, to the best of our knowledge, of a diode-pumped Tm:LuScO3 laser. Efficient and broadly tunable continuous wave operation in the 1973-2141 nm region and femtosecond mode-locking through the use of an ion-implanted InGaAsSb quantum-well-based semiconductor saturable absorber mirror are realized. When mode-locked, near-transform-limited pulses as short as 170 fs were generated at 2093 nm with an average output power of 113 mW and a pulse repetition frequency of 115.2 MHz...
March 15, 2018: Optics Letters
Haizhou Huang, Jianhong Huang, Yan Ge, Hui Zheng, Wen Weng, Hongchun Wu, Wenxiong Lin
We realize Ho laser operation in a composite Tm/Ho:YAG gain medium for the first time, to the best of our knowledge, which was integrated via diffusion bonding the Tm-doped and Ho-doped crystals into a single bulk structure. A maximum output power around 6 W was obtained with a slope efficiency of 40.1% and conversion efficiency (CE) of 33.6% from the absorbed 785 nm laser diode to 2122 nm Ho laser, which is comparable with CE in 1.9 μm LD pumped Ho lasers. Such a scheme is demonstrated to be another valid way for Ho laser generation here, which is of significance to be adopted in other host media or waveguide structures for an assessable, compact, and efficient Ho laser...
March 15, 2018: Optics Letters
Rong Ma, Wei Liu, Zhongzhong Qin, Xiaolong Su, Xiaojun Jia, Junxiang Zhang, Jiangrui Gao
Using a nondegenerate four-wave mixing (FWM) process based on a double-Λ scheme in hot cesium vapor, we demonstrate a compact diode-laser-pumped quantum light source for the generation of quantum correlated twin beams with a maximum squeezing of 6.5 dB. The squeezing is observed at a Fourier frequency in the audio band down to 0.7 kHz which, to the best of our knowledge, is the first observation of sub-kilohertz intensity-difference squeezing in an atomic system so far. A phase-matching condition is also investigated in our system, which confirms the spatial-multi-mode characteristics of the FWM process...
March 15, 2018: Optics Letters
Y K Lin, Q H Wu, S Z Wang, A H Wu, L B Su, L H Zheng, J F Chen, Z P Qin, G Q Xie, X D Xu, Q S Song, Q H Yang
The Nd3+ -doped Bi4 Ge3 O12 (BGO) single-crystal fiber (SCF) was successfully grown by the micro-pulling-down method with the resistance heating system. The fluorescence spectrum and transmission spectrum of the Nd:BGO SCF were measured. Excited by a continuous-wave 808-nm laser diode, a fluorescence peak around 1064 nm was observed. At an absorbed pump power of 15.25 W, the Nd:BGO SCF laser delivered a power of 3.37 W with a slope efficiency of 31.2%.
March 15, 2018: Optics Letters
Michael Kolano, Benedict Gräf, Stefan Weber, Daniel Molter, Georg von Freymann
We demonstrate a polarization-multiplexed, single-laser system for terahertz (THz) time-domain spectroscopy without an external delay line. The fiber laser emits two pulse trains with independently adjustable repetition rates, utilizing only one laser-active section and one pump diode. With a standard fiber-coupled THz setup and a polarization-multiplexed optical amplifier, we are able to measure transients with a spectral bandwidth of 1.5 THz and a dynamic range of 50 dB in a measurement time of 1 s. Based on the novel laser architecture, we call this new approach single-laser polarization-controlled optical sampling, or SLAPCOPS...
March 15, 2018: Optics Letters
Shuhei Okuyama, Tadanobu Nagaya, Kazuhide Sato, Fusa Ogata, Yasuhiro Maruoka, Peter L Choyke, Hisataka Kobayashi
Near-infrared photoimmunotherapy (NIR-PIT), a promising cancer therapy utilizing an antibody-photoabsorber conjugate (APC) and NIR light, which induces rapid necrotic cell death only in APC-bound cells. Effective NIR-PIT in mouse models has been achieved using superficial light illumination (SLI) with light emitting diodes (LEDs) or lasers, but in the clinical setting, fiber optic diffusers have been employed to deliver light to deeper tumors. However, the performance of NIR light in tissue delivered by fiber optic diffusers is poorly understood...
February 16, 2018: Oncotarget
Michael Schwake, Andrei Nemes, Jana Dondrop, Juliane Schroeteler, Stephanie Schipmann, Volker Senner, Walter Stummer, Christian Ewelt
BACKGROUND: Light irradiation (635 nm) of cells containing protoporphyrin IX (PPIX) after 5- aminolevulinic acid (5-ALA) pretreatment causes cell death via different pathways including apoptosis and necrosis, as previously demonstrated for malignant glioma cells. OBJECTIVE: To elucidate whether various malignant pediatric brain tumors, which have been shown to accumulate PPIX, would also be susceptible to photodynamic therapy (PDT). METHODS: Medulloblastoma (DAOY, UW228), pNET (PFSK-1), and rhabdoid tumor (BT16) cell lines were incubated with 5-ALA in variable concentrations for 4 h...
March 12, 2018: Neurosurgery
Vo Truong Nhu Ngoc, Trinh Do Van Nga, Dinh-Toi Chu, Le Quynh Anh
Hemophilia-a bleeding disorder due to the lack of clotting factors-is mostly induced by genetic factors. Its most common type is hemophilia A. Hemorrhage in hemophilia A may occur in several different sites of the body, including those inside the oral cavity, such as mucous membrane and gum. However, only a few studies and case reports on dental issues of hemophilia A patients have been conducted. In clinical dentistry, treatment procedures are invasive, possibly leading to more severe bleeding, especially in hemophilia A cases...
March 14, 2018: Special Care in Dentistry
Robson Almeida de Rezende, Daniela Nascimento Silva, Lúcio Frigo
To evaluate low-level laser therapy (LLLT) as an adjunct to enhance postoperative mouth opening after orthognathic surgery. Prospective clinical trial of 82 patients allocated into an intervention group (laser, LG) and a control group (no laser, CG) and subgroups according to the procedure type : (1) surgically assisted rapid maxillary expansion (SARME); (2) maxillary surgery; (3) mandibular surgery; or (4) bimaxillary surgery. LG patients received LLLT immediately after surgery and every 24 h thereafter for 3 days, using a gallium-aluminum-arsenide (GaAlAs) diode laser (780 nm, 28 spots, 14 on each side of the face, output power 2 J/spot)...
March 12, 2018: Lasers in Medical Science
Haizhou Huang, Jianhong Huang, Huagang Liu, Jinhui Li, Zixiong Lin, Yan Ge, Shutao Dai, Jing Deng, Wenxiong Lin
We demonstrate an enhancement mechanism and thermal model for intra-cavity pumped lasers, where resonance enhancement in intra-cavity pumped Ho laser was achieved by manipulating the wavelength-drift nature of the Tm laser for the first time. Optical conversion efficiency of 37.5% from an absorbed 785 nm diode laser to a Ho laser was obtained with a maximum output power of 7.51 W at 2122 nm, which is comparable to the conversion efficiency in 1.9 μm LD pumped Ho lasers. Meanwhile, more severe thermal effects in the Ho-doped gain medium than the Tm-doped one at high power operation were verified based on the built thermal model...
March 5, 2018: Optics Express
Xiaoming Chen, Yanhua Lu, Hao Hu, Lixin Tong, Lei Zhang, Yi Yu, Juntao Wang, Huaijin Ren, Liu Xu
We present investigations into a narrow-linewidth, quasi-continuous-wave pulsed all-solid-state amplified spontaneous emission (ASE) source by use of a novel multiple-pass zigzag slab amplifier. The SE fluorescence emitted from a Nd:YAG slab active medium acts as the seed and is amplified back and forth 8 times through the same slab. Thanks to the angular multiplexing nature of the zigzag slab, high-intensity 1064-nm ASE output can be produced without unwanted self-lasing in this configuration. Experimentally, the output energy, optical conversion efficiency, pulse dynamics, spectral property, and beam quality of the ASE source are studied when the Nd:YAG slab end-pumped by two high-brightness laser diode arrays...
March 5, 2018: Optics Express
Liangbi Su, Xinsheng Guo, Dapeng Jiang, Qinghui Wu, Zhipeng Qin, Guoqiang Xie
3 at.% Er:SrF2 laser crystals with high optical quality were successfully grown using the temperature gradient technique (TGT). The intense mid-infrared emission was observed around 2.7 μm with excitation by a 970 nm LD. Based on the Judd-Ofelt theory, the emission cross-sections of the4 I13/2 -4 I11/2 transition were calculated by using the Fuchtbauer-Ladenburg (FL) method. Efficient continuous-wave laser operation at 2.8 µm was achieved with the lightly-doped 3 at.% Er:SrF2 crystal pumped by a 970 nm laser diode...
March 5, 2018: Optics Express
Ximing Ren, Peter W R Connolly, Abderrahim Halimi, Yoann Altmann, Stephen McLaughlin, Istvan Gyongy, Robert K Henderson, Gerald S Buller
A CMOS single-photon avalanche diode (SPAD) quanta image sensor is used to reconstruct depth and intensity profiles when operating in a range-gated mode used in conjunction with pulsed laser illumination. By designing the CMOS SPAD array to acquire photons within a pre-determined temporal gate, the need for timing circuitry was avoided and it was therefore possible to have an enhanced fill factor (61% in this case) and a frame rate (100,000 frames per second) that is more difficult to achieve in a SPAD array which uses time-correlated single-photon counting...
March 5, 2018: Optics Express
M D Rotondaro, B V Zhdanov, M K Shaffer, R J Knize
We performed a measurement of the beam quality of an optimized moderate power cesium Diode Pumped Alkali Laser (DPAL). The DPAL used a stable resonator and operated in continuous wave mode using a static cell filled with metallic cesium and a mixture of methane and helium at 200 and 400 torr respectively. In this work, we characterized the spatial quality of the DPAL output beam. As a result of these experiments we determined the output beam quality was excellent (M2 < 1.2) in the whole range of pump power used (up to 11...
March 5, 2018: Optics Express
Yulei Bai, Yanzhou Zhou, Zhaoshui He, Shengli Xie
A new method for the synthesis of wavenumber series before and after mode hopping is proposed for depth-resolved wavenumber scanning interferometry. The classical Fourier transform is not suitable for mode hopping; consequently, the wavenumber scanning range of diode lasers is rather narrow, reducing the depth resolution and measurement accuracy. We show that the discontinuity in wavenumber domain interferograms caused by mode hopping can be removed by introducing the phase compensation of the interference spectrum...
March 5, 2018: Optics Express
Mustafa Cem Terzi, Cihan Agalar, Sari Habip, Aras Emre Canda, Naciye Cigdem Arslan, Funda Obuz
BACKGROUND: Primary closure of the fistula tract using energy emitted by a radial fiber connected to a diode laser is a novel procedure for treating perianal fistulas. OBJECTIVE: The aim of this study was to determine the long-term effectiveness of this new technique. DESIGN: The surgical objective was to seal the fistula tract using laser energy. SETTINGS: The study was conducted at a single day-case surgery center...
March 8, 2018: Diseases of the Colon and Rectum
Robert Naumann, Martin Goez
We present a novel photoredox catalytic system that delivers synthetically useable concentrations of hydrated electrons when illuminated with a green light-emitting diode (LED). The catalyst is a ruthenium complex protected by an anionic micelle, and the urate dianion serves as sacrificial donor confined to the aqueous bulk. Through its chemical properties, that donor not only suppresses charge recombination that would limit the electron yield but also enables this system to perform cross couplings via hydrated electrons, for which we report the first examples...
March 12, 2018: Chemistry: a European Journal
Fetch more papers »
Fetching more papers... Fetching...
Read by QxMD. Sign in or create an account to discover new knowledge that matter to you.
Remove bar
Read by QxMD icon Read

Search Tips

Use Boolean operators: AND/OR

diabetic AND foot
diabetes OR diabetic

Exclude a word using the 'minus' sign

Virchow -triad

Use Parentheses

water AND (cup OR glass)

Add an asterisk (*) at end of a word to include word stems

Neuro* will search for Neurology, Neuroscientist, Neurological, and so on

Use quotes to search for an exact phrase

"primary prevention of cancer"
(heart or cardiac or cardio*) AND arrest -"American Heart Association"