41 research outputs found

    Frequency comb assisted two-photon vibrational spectroscopy

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    We report a setup for high-resolution two-photon spectroscopy using a mid-infrared continuous wave optical parametric oscillator (CW-OPO) and a near-infrared diode laser as the excitation sources, both of which are locked to fully stabilized optical frequency combs. The diode laser is directly locked to a commercial near-infrared optical frequency comb using an optical phase-locked loop. The near-infrared frequency comb is also used to synchronously pump a degenerate femtosecond optical parametric oscillator to produce a fully stabilized mid-infrared frequency comb. The beat frequency between the mid-infrared comb and the CW-OPO is then stabilized through frequency locking. We used the setup to measure a double resonant two-photon transition to a symmetric vibrational state of acetylene with a sub-Doppler resolution and high signal-to-noise ratio. (C) 2017 Optical Society of AmericaPeer reviewe

    Step-modulated decay cavity ring-down detection for double resonance spectroscopy

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    A method of measuring double resonant two-photon signal and background from a single cavity ring-down decay is introduced. This is achieved by modulating the double resonance loss via one of the light sources exciting the transition. The noise performance of the method is characterized theoretically and experimentally. The addition of a new parameter to the fitting function introduces a minor noise increase due to parameter correlation. However, the concurrent recording of the background can extend the stable measurement time. Alternatively, the method allows a faster measurement speed, while still recording the background, which is often advantageous in double resonance measurements. Finally, the method is insensitive to changes in the cavity decay rate at short timescales and can lead to improved performance if they have significant contribution to the final noise level compared to the detector noise. (C) 2018 Optical Society of America under the terms of the OSA Open Access Publishing AgreementPeer reviewe

    What makes people approve or condemn mind upload technology? Untangling the effects of sexual disgust, purity, and science fiction familiarity

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    The idea of separating a person's consciousness and transferring it to another medium-'mind upload'-is being actively discussed in science, philosophy, and science fiction. Mind upload technologies are currently also being developed by private companies in Silicon Valley, and similar technological developments have received significant funding in the EU. Mind upload has important existential and ethical implications, yet little is known about how ordinary people actually feel about it. The current paper aims to provide a thorough moral psychological evaluation about various cognitive factors that explain people's feelings and reactions towards the use of mind upload technology. In four studies (including pilot) with a total of 952 participants, it was shown that biological and cultural cognitive factors help to determine how strongly people condemn mind upload. Both experimental manipulations in a laboratory and cross-sectional correlative online study designs were employed. The results showed that people who value purity norms and have higher sexual disgust sensitivity are more inclined to condemn mind upload. Furthermore, people who are anxious about death and condemn suicidal acts were more accepting of mind upload. Finally, higher science fiction literacy and/or hobbyism strongly predicted approval of mind upload. Several possible confounding factors were ruled out, including personality, values, individual tendencies towards rationality, and theory of mind capacities. Possible idiosyncrasies in the stimulus materials (whether consciousness is uploaded onto a computer, chimpanzee, artificial brain, or android; and whether the person's body physically dies during the process) were ruled out. The core findings inform ongoing philosophical discussions on how mind upload could (or should) be used in the future, and imply that mind upload is a much more salient topic for the general population than previously thought.Peer reviewe

    Synovial fluid detection in intra-articular injections using a bioimpedance probe (BIP) needle-a clinical study

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    Intra-articular glucocorticoid injections are the recommended treatment for active arthritis, but accurate positioning of the needle may be challenging. Inexperienced physicians might decide not to inject because an unsuccessful injection impairs clinical outcome and may lead to complications; however, choosing not to inject may impair or delay the best possible treatment. Here, we address this problem by introducing a novel Bioimpedance Probe (BIP) Needle-guidance method that was tested in a clinical study. The BIP Needle was utilized for detection of synovial fluid. It measures real-time bioimpedance spectra and identifies when the needle tip is in contact with the synovial fluid. Injections into 80 joints with active arthritis were performed by an experienced rheumatologist using the BIP Needle. The location of the BIP Needle was ensured by aspiration of synovial fluid, absence of resistance during injection, and/or using real-time ultrasound imaging. Sensitivity and specificity of the device for synovial fluid detection were 86 % (CI 75-93 %) and 85 % (CI 74-92 %), respectively. The BIP Needles showed high spatial resolution and differentiated the synovial fluid from the surrounding tissues. However, lack of synovial fluid, anatomic variability, and intra-articular structures challenged the technology. The BIP Needles provided adequate results in intra-articular injections. Performance of the device was good even in small joints, which may be the most difficult for inexperienced physicians. Further performance improvement can be expected when more data is collected for mathematical models. Overall, this novel method showed potential to be used in real-time needle guidance.Peer reviewe

    Moral psychology of sex robots : An experimental study − how pathogen disgust is associated with interhuman sex but not interandroid sex

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    The idea of sex with robots seems to fascinate the general public, raising both enthusiasm and revulsion. We ran two experimental studies (Ns = 172 and 260) where we compared people’s reactions to variants of stories about a person visiting a bordello. Our results show that paying for the services of a sex robot is condemned less harshly than paying for the services of a human sex worker, especially if the payer is married. We have for the first time experimentally confirmed that people are somewhat unsure about whether using a sex robot while in a committed monogamous relationship should be considered as infidelity. We also shed light on the psychological factors influencing attitudes toward sex robots, including disgust sensitivity and interest in science fiction. Our results indicate that sex with a robot is indeed genuinely considered as sex, and a sex robot is genuinely seen as a robot; thus, we show that standard research methods on sexuality and robotics are also applicable in research on sex robotics.Peer reviewe

    Broadband photoacoustic spectroscopy of 14CH4 with a high-power mid-infrared optical frequency comb

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    We report a photoacoustic spectroscopy setup with a high-power mid-infrared frequency comb as the light source. The setup is used in broadband spectroscopy of radiocarbon methane. Owing to the high sensitivity of a cantilever-enhanced photoacoustic cell and the high-power light source, we can reach a detection limit below 100 ppb in a broadband measurement with a sample volume of only a few milliliters. The first infrared spectrum of 14CH4 is reported and given a preliminary assignment. The results lay a foundation for the development of optical detection systems for radiocarbon methane.We report a photoacoustic spectroscopy setup with a high-power mid-infrared frequency comb as the light source. The setup is used in broadband spectroscopy of radiocarbon methane. Owing to the high sensitivity of a cantilever-enhanced photoacoustic cell and the high-power light source, we can reach a detection limit below 100 ppb in a broadband measurement with a sample volume of only a few milliliters. The first infrared spectrum of (CH4)-C-14 is reported and given a preliminary assignment. The results lay a foundation for the development of optical detection systems for radiocarbon methane. (c) 2019 Optical Society of AmericaPeer reviewe

    Traumatic lumbar punctures in diagnostic and intrathecal treatment punctures of pediatric hemato-oncology patients

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    Successful first diagnostic lumbar puncture (LP) is crucial because intrathecal chemotherapy has not yet protected the central nervous system against cancer cells. If blood contaminates the cerebrospinal fluid (CSF) with blasts, they may enter the central neural system and compromise the patient's health. We retrospectively determined the incidence of traumatic lumbar punctures (TLP) in 2,507 LPs of 250 pediatric hemato-oncology patients aged from one to 18 years, including both diagnostic and intrathecal treatment procedures, and 2,617 LPs of 1,525 other age-matched pediatric patients. We used >= 10 erythrocytes/mu L in the CSF sample as the criterion of TLP. TLPs were less frequent in hemato-oncology patients than in other patients (31.6% vs. 48.5%, p < 0.0001). The incidence of TLP was significantly lower in the first diagnostic LP than in subsequent intrathecal treatment LPs (20.5% vs. 31.6%, p = 0.0046). According to logistic regression analysis, the odds of TLP was 1.6-fold if the LP procedure was not performed in the hemato-oncology department. The odds of the patient's next LP being traumatic were threefold if the previous first LP was traumatic. A week or less time between the first and next LP tripled the odds of TLP as well. The patient's age category was not significantly associated with the incidence of TLP. Given the risks of TLP, hemato-oncology patients' first diagnostic LP should include administration of chemotherapy, as generally recommended, and be performed under general anesthesia or deep sedation by an experienced physician to optimize not only the success of the first LP procedure but also following procedures

    Real-time detection of cerebrospinal fluid with bioimpedance needle in paediatric lumbar puncture

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    Background Lumbar puncture is a common clinical procedure that can occasionally be difficult. Various needle guidance methods can facilitate performing this procedure, but at the expense of special expertise, equipment and facility. In the present study, we evaluated the clinical feasibility of a novel bioimpedance needle system regarding its ability to detect cerebrospinal fluid (CSF) in paediatric lumbar punctures.Methods We performed 40 lumbar puncture procedures using the bioimpedance needle system in 37 paediatric patients, aged from 0 days to 17 months, as a part of their prescribed examinations in two university hospitals. The bioimpedance needle is similar to a conventional 22G cutting-edge spinal needle with a stylet, except the needle and stylet are configured as a bipolar electrode with high spatial resolution. The system measures in real-time when the needle tip reaches the subarachnoid space containing CSF. The procedure was considered successful when the erythrocyte count was determined from the obtained CSF sample.Results Subarachnoid space was verifiably reached in 28 out of 40 procedures (70%). Bioimpedance needle system detected CSF in 23 out of these 28 successful procedures (82%) while failed in 3 out of 28 procedures (11%). No adverse events were reported.Conclusion Bioimpedance spinal needle system was found clinically feasible in paediatric lumbar punctures, and it may offer an objective and simple means to detect the time point when the needle tip is in contact with the cerebrospinal fluid.</div

    Double resonant absorption measurement of acetylene symmetric vibrational states probed with cavity ring down spectroscopy

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    A novel mid-infrared/near-infrared double resonant absorption setup for studying infrared-inactive vibrational states is presented. A strong vibrational transition in the mid-infrared region is excited using an idler beam from a singly resonant continuous-wave optical parametric oscillator, to populate an intermediate vibrational state. High output power of the optical parametric oscillator and the strength of the mid-infrared transition result in efficient population transfer to the intermediate state, which allows measuring secondary transitions from this state with a high signal-to-noise ratio. A secondary, near-infrared transition from the intermediate state is probed using cavity ring-down spectroscopy, which provides high sensitivity in this wavelength region. Due to the narrow linewidths of the excitation sources, the rovibrational lines of the secondary transition are measured with sub-Doppler resolution. The setup is used to access a previously unreported symmetric vibrational state of acetylene, nu(1) + nu(2) + nu(3) + nu(1)(4) + nu(-1)(5) in the normal mode notation. Single-photon transitions to this state from the vibrational ground state are forbidden. Ten lines of the newly measured state are observed and fitted with the linear least-squares method to extract the band parameters. The vibrational term value was measured to be at 9775.0018(45) cm(-1), the rotational parameter B was 1.162 222(37) cm(-1), and the quartic centrifugal distortion parameter D was 3.998(62) x 10(-6) cm(-1), where the numbers in the parenthesis are one-standard errors in the least significant digits. Published by AIP Publishing.Peer reviewe

    Moral psychology of nursing robots : Exploring the role of robots in dilemmas of patient autonomy

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    Artificial intelligences (AIs) are widely used in tasks ranging from transportation to healthcare and military, but it is not yet known how people prefer them to act in ethically difficult situations. In five studies (an anthropological field study, n = 30, and four experiments, total n = 2150), we presented people with vignettes where a human or an advanced robot nurse is ordered by a doctor to forcefully medicate an unwilling patient. Participants were more accepting of a human nurse's than a robot nurse's forceful medication of the patient, and more accepting of (human or robot) nurses who respected patient autonomy rather than those that followed the orders to forcefully medicate (Study 2). The findings were robust against the perceived competence of the robot (Study 3), moral luck (whether the patient lived or died afterwards; Study 4), and command chain effects (Study 5; fully automated supervision or not). Thus, people prefer robots capable of disobeying orders in favour of abstract moral principles like valuing personal autonomy. Our studies fit in a new era in research, where moral psychological phenomena no longer reflect only interactions between people, but between people and autonomous AIs.Peer reviewe
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