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Pulsed light OR IPL

Xiang Zhong, Xicheng Gao, Huaxia Deng, Shisong Zhao, Mengchao Ma, Jin Zhang, Jianquan Li
A pulse-width multiplexing method for reducing the nuisance-alarm rate of a phase-sensitive optical time-domain reflectometer ( ϕ -OTDR) is described. In this method, light pulses of different pulse-widths are injected into the sensing fiber; the data acquired at different pulse-widths are regarded as the outputs of different sensors; and these data are then processed by a multisensor data fusion algorithm. In laboratory tests with a sensing fiber on a vibrating table, the effects of pulse-width on the signal-to-noise ratio (SNR) of the ϕ -OTDR data are observed...
October 18, 2018: Sensors
Wenjin Wang, Albertus C den Brinker, Gerard de Haan
This paper introduces a new method to automate heart-rate detection using remote photoplethysmography (rPPG). The method replaces the commonly used region of interest (RoI) detection and tracking, and does not require initialization. Instead, it combines a number of candidate pulse-signals computed in the parallel, each biased towards differently colored objects in the scene. The method is based on the observation that the temporally averaged colors of video objects (skin and background) are usually quite stable over time in typical application-driven scenarios, such as the monitoring of a subject sleeping in bed, or an infant in an incubator...
August 1, 2018: Biomedical Optics Express
Jianbei Huang, Henrik Hartmann, Heidi Hellén, Armin Wisthaler, Erica Perreca, Alexander Weinhold, Alexander Rücker, Nicole M van Dam, Jonathan Gershenzon, Susan E Trumbore, Thomas Behrendt
Volatile organic compounds (VOC) play important roles in atmospheric chemistry, plant ecology and physiology, and biogenic VOC (BVOC) emitted by plants is the largest VOC source. Our knowledge about how environmental drivers (e.g. carbon, light and temperature) may regulate BVOC emissions is limited because they are often not controlled. We combined a greenhouse facility to manipulate atmospheric CO2 ([CO2 ]) with proton-transfer-reaction mass spectrometry (PTR-MS) and cavity ring-down spectroscopy to investigate the regulation of BVOC in Norway spruce...
October 18, 2018: Environmental Science & Technology
John B West, Daniel L Wang, Gordon Kim Prisk, Janelle M Fine, Amy Bellinghausen, Matthew P Light, Daniel R Crouch
A new noninvasive method was used to measure the impairment of pulmonary gas exchange in 34 patients with lung disease, and the results were compared with the traditional ideal alveolar-arterial PO2 difference (A-aDO2 ) calculated from arterial blood gases. The end-tidal PO2 was measured from the expired gas during steady-state breathing, the arterial PO2 was derived from a pulse oximeter if the SpO2 was 95% or less, which was the case for 23 patients. The difference between the end-tidal and the calculated PO2 was defined as the Oxygen Deficit...
October 18, 2018: American Journal of Physiology. Lung Cellular and Molecular Physiology
Satoshi Iihama, Yong Xu, Marwan Deb, Grégory Malinowski, Michel Hehn, Jon Gorchon, Eric E Fullerton, Stéphane Mangin
All-optical ultrafast magnetization switching in magnetic material thin film without the assistance of an applied external magnetic field is explored for future ultrafast and energy-efficient magnetic storage and memories. It is shown that femtosecond (fs) light pulses induce magnetization reversal in a large variety of magnetic materials. However, so far, only GdFeCo-based ferrimagnetic thin films exhibit magnetization switching via a single optical pulse. Here, the single-pulse switching of Co/Pt multilayers within a magnetic spin-valve structure ([Co/Pt]/Cu/GdFeCo) is demonstrated and four possible magnetic configurations of the spin valve can be accessed using a sequence of single fs light pulses...
October 18, 2018: Advanced Materials
Tihana Žugčić, Radhia Abdelkebir, Francisco J Barba, Anet Rezek-Jambrak, Fernando Gálvez, Sol Zamuz, Daniel Granato, José M Lorenzo
Physicochemical parameters (pH, colour and texture), proximate composition (moisture, protein, lipid and ash content), amino acid content, and taste profile of beef patties elaborated with soy (control), pulses (pea, lentil and bean) and microalgal ( Chlorella and Spirulina ) proteins were assessed. The pH, colour, ash content, total, essential and non-essential amino acids and amino acid content were significantly different among the beef patties studied. In this regard, beef patties prepared with pea protein presented the highest values for pH; whereas beef patties manufactured with pea also showed the highest values for lightness and patties elaborated with bean the highest values for redness...
November 2018: Journal of Food Science and Technology
Ohad Yossef Hay, Meir Cohen, Itamar Nitzan, Yair Kasirer, Sarit Shahroor-Karni, Yitzhak Yitzhaky, Shlomo Engelberg, Meir Nitzan
Oxygen saturation in arterial blood (SaO₂) provides information about the performance of the respiratory system. Non-invasive measurement of SaO₂ by commercial pulse oximeters (SpO₂) make use of photoplethysmographic pulses in the red and infrared regions and utilizes the different spectra of light absorption by oxygenated and de-oxygenated hemoglobin. Because light scattering and optical path-lengths differ between the two wavelengths, commercial pulse oximeters require empirical calibration which is based on SaO₂ measurement in extracted arterial blood...
October 15, 2018: Sensors
Shou Yu Zhang, Chen Xiang, Xi Jie Zhou, Shu Rong Liu, Xiao Peng Cheng, Kai Wang
The study of photosynthetic fluorescence characteristics of algae is important for the analy-sis of photosynthesis and carbon sequestration of algae. In July 2017, six common species of macroalgae found in Gouqi seaweed beds were collected, including Ulva pertusa, Cladophora stimpsonii, Grateloupia livida, Sargassum thunbergii, Polysiphonia urceolata, and Hizikia fusifarme. In the field, the maximal quantum yieids of photosystem2(Fv /Fm ) and rapid curves (RLCs) were mea-sured by using pulse-amplitude modulated fluorometer (Diving-PAM)...
October 2018: Ying Yong Sheng Tai Xue Bao, the Journal of Applied Ecology
XiaoZhao Zhang, Nan Song, Lan Gong
PURPOSE: To evaluate the clinical efficacy of Lumenis® M22TM intense pulse light (IPL) in reduction of ocular Demodex infestation in eyelashes in a prospective study. METHODS: Forty patients with ocular demodicosis were recruited. Then half were randomly picked to receive the IPL treatment, while the other half got 5% tea tree oil (as the control group). Demodex counts, the ocular surface disease index (OSDI) score, lid margin abnormalities, conjunctival congestion, tear break up time (TBUT), corneal staining with fluorescein, meibomian gland (MG) expressibility, meibum quality, modified Schirmer I test with anaesthetic (SIT), were assessed on the day before treatment and after treatment of 30 days and 90 days...
October 15, 2018: Current Eye Research
Yu Sawashima, Daiki Yamanaka, Itsuki Takamoto, Atsushi Matsunaka, Yasuhiro Awatsuji, Kenzo Nishio
Light-in-flight (LIF) recording by holography is a powerful technique for observing ultrashort light pulse propagation. However, the recordable time of the technique has been limited by the lateral length of the holographic plate. Then, to extend the recordable time of LIF recording by holography, we proposed a space-division multiplexing technique of holograms, which divides the holographic plate longitudinally and uses double reference light pulses. We experimentally demonstrated that the recordable time becomes twice as long as before for the first time, to the best of our knowledge, using the proposed technique...
October 15, 2018: Optics Letters
Hannah L Nathan, Nicola Vousden, Elodie Lawley, Annemarie de Greeff, Natasha L Hezelgrave, Nicola Sloan, Nina Tanna, Shivaprasad S Goudar, Muchabayiwa F Gidiri, Jane Sandall, Lucy C Chappell, Andrew H Shennan
Objectives: Haemorrhage, hypertension, sepsis and abortion complications (often from haemorrhage or sepsis) contribute to 60% of all maternal deaths. Each is associated with vital signs (blood pressure (BP) and pulse) abnormalities, and the majority of deaths are preventable through simple and timely intervention. This paper presents the development and evaluation of the CRADLE Vital Signs Alert (VSA), an accurate, low-cost and easy-to-use device measuring BP and pulse with an integrated traffic light early warning system...
October 2018: BMJ Innovations
Giulio Simone, Dario Di Carlo Rasi, Xander de Vries, Gaël H L Heintges, Stefan C J Meskers, René A J Janssen, Gerwin H Gelinck
Photovoltaic retinal prostheses show great potential to restore sight in patients suffering from degenerative eye diseases by electrical stimulation of the surviving neurons in the retinal network. Herein, organic photodiodes (OPDs) sensitive to near-infrared (NIR) light are evaluated as photovoltaic pixels for future application in retinal prostheses. Single-junction and tandem OPDs are compared. In the latter, two nominally identical single-junction cells are processed on top of each other, effectively doubling the open-circuit voltage (V OC )...
October 15, 2018: Advanced Materials
S W G J W Chinthaka, R L Satarasinghe, S Senanayake, W A P S R Weerarathne, A A M Anfaz, M P Deraniyagala
BACKGROUND: Lymphadenopathy is not an uncommon presentation of adult onset Still's disease: it is present in up to two thirds of patients with adult onset Still's disease. The characteristic appearance of lymphadenopathy is described as intense, paracortical immunoblastic hyperplasia. Changes in light microscopy may resemble lymphoma, but immunohistochemistry reveals a benign polyclonal B cell hyperplasia. CASE PRESENTATION: We describe a 67-year-old Sri Lankan woman who manifested relapsing prolonged fever, raised inflammatory markers, arthralgia, myalgia, transient skin rash, and cervical lymphadenopathy histologically characterized by noncaseating granulomatous adenitis with central suppuration...
October 15, 2018: Journal of Medical Case Reports
Victoria Strong, Torsten Möller, Ann-Sofie Tillman, Stefan Träff, Louise Guevara, Mike Martin, Sharon Redrobe, Kate White
OBJECTIVE: To characterize the cardiopulmonary characteristics of two different anaesthetic protocols (tiletamine/zolazepam ± medetomidine) and their suitability for the immobilization of healthy chimpanzees undergoing cardiac assessment. STUDY DESIGN: Prospective, clinical, longitudinal study. ANIMALS: Six chimpanzees (Pan troglodytes) aged 4-16 years weighing 19.5-78.5 kg were anaesthetized on two occasions. METHODS: Anaesthesia was induced with tiletamine/zolazepam (TZ) (3-4 mg kg-1 ) or tiletamine/zolazepam (2 mg kg-1 ) and medetomidine (0...
August 23, 2018: Veterinary Anaesthesia and Analgesia
Himadri Shekhar Dhar, Matthias Zens, Dmitry O Krimer, Stefan Rotter
Mesoscopic spin ensembles coupled to a cavity offer the exciting prospect of observing complex nonclassical phenomena that pool the microscopic features from a few spins with those of macroscopic spin ensembles. Here, we demonstrate how the collective interactions in an ensemble of as many as a hundred spins can be harnessed to obtain a periodic pulse train of nonclassical light. To unravel the full quantum dynamics and photon statistics, we develop a time-adaptive variational renormalization group method that accurately captures the underlying Lindbladian dynamics of the mesoscopic spin-cavity system...
September 28, 2018: Physical Review Letters
Matthew P Light, Thalia N Casimire, Catherine Chua, Viachaslau Koushyk, Omar E Burschtin, Indu Ayappa, David M Rapoport
RATIONALE: Home sleep apnea testing (HSAT) typically does not include electroencephalogram (EEG) monitoring for sleep assessment. In patients with insomnia and low sleep efficiency, overestimation of the sleep period can result from absence of EEG, which will reduce sleep disordered breathing (SDB) indices and may lead to a false-negative result. OBJECTIVE: To validate a single channel frontal EEG for scoring sleep versus wake against full EEG during polysomnography, and then to examine the utility of adding this single channel EEG to standard HSAT to prevent false-negative results...
October 11, 2018: Sleep & Breathing, Schlaf & Atmung
Todd L Stincic, Pasha Grachev, Martha A Bosch, Oline K Rønnekleiv, Martin J Kelly
Energy balance is regulated by anorexigenic proopiomelanocortin (POMC) and orexigenic neuropeptide Y/agouti-related peptide (NPY/AgRP) neurons of the hypothalamic arcuate nucleus. POMC neurons make extensive projections and are thought to release both amino acid and peptide neurotransmitters. However, whether they communicate directly with NPY/AgRP neurons is debated. Initially, using single-cell RT-PCR, we determined that mouse POMCeGFP neurons express Slc17a6 ( Vglut2 ) and Slc18a2 ( Vmat2 ), but not Slc31a1 ( Vgat ) mRNA, suggesting glutamate and non-canonical GABA release...
July 2018: ENeuro
YunKyoung Ko, Seong Dae Yun, Suk-Min Hong, Yonghyun Ha, Chang-Hoon Choi, N Jon Shah, Jörg Felder
PURPOSE: Functional MRI (fMRI) is a well-established method used to investigate localised brain activation by virtue of the blood oxygen level dependent (BOLD) effect. It often relies on visual presentations using beam projectors, liquid crystal display (LCD) screens, and goggle systems. In this study, we designed an MR compatible, low-cost display unit based on organic light-emitting diodes (OLED) and demonstrated its performance. METHODS: A 3.8" dual OLED module and an MIPI-to-HDMI converter board were used...
2018: PloS One
Jing Liu, Bryan Yan, Yuanting Zhang, Xiao-Rong Ding, Su Peng, Ni Zhao
OBJECTIVE: To fight the "silent killer" hypertension, continuous blood pressure (BP) monitoring has been one of the most desired functions in wearable electronics. However, current BP measuring principles and protocols either involve a vessel occlusion process with a cuff or require multiple sensing nodes on the body, which makes it difficult to implement them in compact wearable electronics like smartwatches and wristbands with long-term wearability. METHODS: In this work, we proposed a highly-compact multi-wavelength photoplethysmography (MWPPG) module and a depth-resolved MWPPG approach for continuous monitoring of BP and systemic vascular resistance (SVR)...
October 9, 2018: IEEE Transactions on Bio-medical Engineering
P Yu Serdobintsev, A S Melnikov, A A Pastor, N A Timofeev, M A Khodorkovskiy
Direct measurement of the rates of nonradiative relaxation processes in electronically excited xenon clusters was carried out. The clusters were created in a pulsed supersonic beam and two-photon excited by femtosecond laser pulses with a wavelength of 263 nm. The measurements were performed using the pump-probe method and electron spectroscopy. It is shown that relaxation of light clusters XeN (N < 15) predominantly occurs by desorption of excited xenon atoms with a characteristic time constant of 3 ps...
May 21, 2018: Journal of Chemical Physics
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