Small Instrument Research Articles

On seismic ambient noise cross-correlation and surface-wave attenuation

SUMMARY We derive a theoretical relationship between the cross correlation of ambient Rayleigh waves (seismic ambient noise) and the attenuation parameter α associated with Rayleigh-wave propagation. In particular, we derive a mathematical expression for the multiplicative factor relating normalized cross correlation to the Rayleigh-wave Green’s function. Based on this expression, we formulate an inverse problem to determine α from cross correlations of recorded ambient signal. We conduct a preliminary application of our algorithm to a relatively small instrument array, conveniently deployed on an island. In our setup, the mentioned multiplicative factor has values of about 2.5–3, which, if neglected, could result in a significant underestimate of α. We find that our inferred values of α are reasonable, in comparison with independently obtained estimates found in the literature. Allowing α to vary with respect to frequency results in a reduction of misfit between observed and predicted cross correlations.

Retrograde Intrarenal Surgery: Scopes, lasers and disposables (part 2)

Flexible instrumentation is the mainstay of minimal invasive stone surgery and this led to the invention of smaller and safer instruments which performed remarkable good to a variety of procedures. Further developments like digital technology and single use ureteroscopes which along with similar technological advances in lasers and disposables transformed flexible surgery in a tool of paramount importance in the intrarenal surgery of various clinical entities. This is the second part of our review of the literature concerning the advances

ScintPi: A Low‐Cost, Easy‐to‐Build GPS Ionospheric Scintillation Monitor for DASI Studies of Space Weather, Education, and Citizen Science Initiatives

AbstractWe report the proposal and results of a low‐cost, easy‐to‐build GPS‐based sensor for detection and monitoring ionospheric irregularities through the detection of amplitude scintillation. The system is based on the Raspberry Pi single‐board computer combined with an Adafruit Ultimate GPS peripheral, which is capable of measuring (at 10‐Hz rate) the intensity of the L1 signals transmitted by GPS satellites. We introduce and discuss results of short‐ and long‐term observations obtained with a prototype of this system deployed in Presidente Prudente, a low magnetic latitude site in Brazil. The deployment and observations were carried out to test the ability of the system to detect ionospheric scintillations and, therefore, monitor the occurrence of ionospheric irregularities associated with equatorial spread F. Our results show that this low‐cost sensor is indeed capable of detecting scintillation events associated with equatorial spread F. Comparison with simultaneous, collocated measurements made by a commercial scintillation monitor are also presented. The joint observations allowed us to quantify the performance of the low‐cost monitor and to identify sources of potential limitations. While the sensor cannot (and it was not intended to) substitute commercial scintillation monitors, the low cost allows its use in studies of ionospheric irregularities (space weather) that require observations made by distributed arrays of small instruments (DASI). Furthermore, the simplicity of the sensor design stimulates its use in educational and citizen science initiatives.

Analysis of ring laser gyroscopes including laser dynamics

Inertial sensors are important at application level and also in fundamental physics. Ring laser gyroscopes, which measure angular rotation rates, are among the most sensitive ones. Large area ring laser reach sensitivities at the level of fractions of prad/s, allowing measurements of relevant geophysical signals. Improvements of a factor 10–100 would make these instruments able to measure general relativity effects; this is the goal e.g. of the GINGER project, an Earth based experiment aiming to test the Lense–Thirring effect with an accuracy of 1%. However, the laser induces non-linearities, effects larger in small scale instruments. We discuss a novel technique to analyse data, able to reduce non-linear laser effects. We apply this technique to data from two ring laser prototypes, and compare the precision of the measurement of the angular rotation rate obtained with the new and the standard methods. We show that the back-scatter problem of the ring laser gyroscopes is negligible with a proper analysis of the data. These results not only allow to improve the performance of large scale ring laser gyroscopes but also pave the way to the development of small scale instruments with nrad/s sensitivity, which are precious for environmental studies and as inertial platforms.

Future of Planetary Atmospheric, Surface, and Interior Science Using Radio and Laser Links

AbstractScientific studies using spacecraft radio links, which are shared with communications and navigation functions, have been carried out on almost every solar system exploration mission in the past five decades. They have led to numerous scientific discoveries as well as technological advances. These radio science experiments have investigated the interior structure of every planet in the solar system and several of their satellites, the Moon, and several comets and asteroids and sounded the atmospheres of every planet in the solar system except Mercury, and the atmospheres of Pluto and several large satellites, the Io Plasma Torus, Saturn's and Uranus' rings, and the solar corona. Future experiments at Mercury, the Jovian system, asteroid Psyche, and other targets are currently in various planning and development phases. Over the next 30 years, significant advances in radio and laser link science technologies, including one order of magnitude improvement achievable in range rate and range accuracy and advanced calibration techniques, could enable many additional scientific breakthroughs. Future exploration concepts focus on applications of small spacecraft and entry probes and can include constellations for studies of atmospheric dynamics, interior structures, and surface properties. Selected science‐enabling technologies specific to small spacecraft instrumentation on future missions are under study. Examples include field tests of radio scattering to determine surface properties, constellations for high‐resolution spatial and temporal atmospheric sounding, small science‐quality software‐defined transponders, miniature ultrastable oscillators, and advanced radio‐metric calibrations at the Deep Space Network.

The prevention of accidental aspiration or swallowing small instruments during implant treatment

The prevention of accidental aspiration or swallowing small instruments during implant treatment

Management of endometrial polyps

The epidemiology of endometrial polyps is reported to be between 7.8 and 50% of women. The range remains quite broad and inconsistent due to confounding study factors such as the method of research, population studied, histological type and anatomical location of polyps. The development of polyps is influenced by a multitude of genetic and epigenetic factors. Chromosomes 6,7 and 12 are incriminated in this process. A fraction of these polyps may undergo malignant transformation, most commonly in postmenopausal patients. 3D ultrasound (US) and hysterosalpingo-contrast-sonography (HyCoSy) provide an accurate diagnosis and location of endometrial polyps (EPs). Expectant management is recommended when the polyp is up to 10mm in length, in asymptomatic young patients. When indicated, hysteroscopic removal of polyps can be performed as an outpatient without requiring a general anaesthetic. The use of a small tip diameter hysteroscope and 5Fr instruments offers safe, efficient and low-cost treatment. The hysteroscopic morcellator and shaver are the best surgical option for bigger polyps since it is a quick and time-effective method with the technique easily learned by surgeons.

Kazoo training for L2 pronunciation practice and reduced foreign accentedness?

ABSTRACTThis paper presents a controlled pretest–training–posttest study on using a small membraphone instrument called kazoo for L2 pronunciation practice and reducing foreign accentedness. Learners were recorded for free speech before and after a six-week pronunciation and oral skills course including L2 prosody training with personal kazoos. A control group did not receive any kazoo training but did similar tasks in regular speech. Samples of all learners’ free speech before and after the course were rated for foreign accentedness by L1 speakers. In addition, learners taking part in the kazoo group were interviewed in focus groups to ascertain their views on kazoo training. The results imply that the kazoo has potential as a pronunciation teaching and learning tool. Even if a group-specific analysis did not yield clear results, developing on an individual level was more common in the kazoo group. Moreover, many of the learners found positive aspects about kazooing. However, problems occurred as well; these are also reported on in this paper to hopefully help others who wish to conduct further teaching experiments and develop specialised tasks and materials for kazoo pronunciation practice.

Rapid Antibiofilm Effect of Ag/ZnO Nanocomposites Assisted by Dental LED Curing Light against Facultative Anaerobic Oral Pathogen Streptococcus mutans.

The integration of nanomaterials with clinical therapeutic instruments is a promising approach to improve the effects of nanomaterials. We reported an efficient synergistic antibacterial strategy formed through the combination of Ag/ZnO nanocomposites with a light-emitting diode (LED) curing light, which is a commonly used small instrument in dental clinics. The as-designed integration depicted a significantly enhanced bactericidal effect on facultative anaerobic oral pathogen Streptococcus mutans (S. mutans) both in planktonic and biofilm phases over a very short irradiation time (≤5 min). Further study showed that the combination of LED and Ag/ZnO nanocomposites induced more ·OH and ·O2- generation, which is responsible for the enhanced antibacterial activity. Moreover, this combination could destroy S. mutans biofilm by killing the bacteria embedded within biofilm, inhibiting exopolysaccharide production and down-regulating the biofilm-related gene expression. Therefore, it is proposed that this combination could be applied in dental clinics to realize dental caries prevention and dental restoration simultaneously.

High Strength and Deformation Mechanisms of Al0.3CoCrFeNi High-Entropy Alloy Thin Films Fabricated by Magnetron Sputtering.

Recently, high-entropy alloy thin films (HEATFs) with nanocrystalline structures and high hardness were developed by magnetron sputtering technique and have exciting potential to make small structure devices and precision instruments with sizes ranging from nanometers to micrometers. However, the strength and deformation mechanisms are still unclear. In this work, nanocrystalline Al0.3CoCrFeNi HEATFs with a thickness of ~4 μm were prepared. The microstructures of the thin films were comprehensively characterized, and the mechanical properties were systematically studied. It was found that the thin film was smooth, with a roughness of less than 5 nm. The chemical composition of the high entropy alloy thin film was homogeneous with a main single face-centered cubic (FCC) structure. Furthermore, it was observed that the hardness and the yield strength of the high-entropy alloy thin film was about three times that of the bulk samples, and the plastic deformation was inhomogeneous. Our results could provide an in-depth understanding of the mechanics and deformation mechanism for future design of nanocrystalline HEATFs with desired properties.

Abstract WP139: MRI Evaluation and Functional Assessment of Brain Injury Improvement After 3K3A-Activated Protein C Treatment for Murine White Matter Stroke

Introduction: Subcortical white matter stroke (WMS) accounts for 25% of all incidences of stroke and results in severe motor and cognitive disability. WMS stands as the second leading cause of dementia and is notably prevalent in older adults. Activated protein C (APC), a plasma serine protease with potent antithrombotic and cell-signaling activities, was engineered to reduce bleeding risk while retaining normal cell-signaling activities (anti-inflammatory, anti-apoptotic, and neuroregenerative, etc. activities). The engineered variant, 3K3A-APC, is neuroprotective in preclinical models of ischemic stroke with large infarcts involving common large arteries and gray matter. A multicenter Phase 2 randomized clinical trial enrolled 110 patients to assess the safety, pharmacokinetics, and efficacy of human recombinant 3K3A-APC in acute ischemic stroke patients following endovascular treatments (NCT02222714). Methods: In this new study, a murine WMS was induced by the vasoconstrictor N5-(1-iminoethyl)-L-ornithine, dihydrochloride (L-Nio) by injection into the subcortical white matter ventral to the mouse forelimb motor cortex using the Neurostar motorized ultra-precise small animal stereotaxic instrument. Mice received intravenously 0.2 mg/kg recombinant murine 3K3A-APC or saline at 4, 24, 48 and 72 h after L-Nio. Then MRI scans were performed using a 7T PET/MRI scanner (MR Solutions) and a standard quadrature coil at 1 and 7 days after the stroke. Results: Both MRI and histological results showed that 3K3A-APC significantly reduced the lesion volume, increased the viability of oligodendrocytes and neurons, and protected against blood brain barrier damage at 1 and 7 days after stroke. Behavioral tests showed that 3K3A-APC improved functional recovery. Conclusions: These results demonstrated that 3K3A-APC might be an effective treatment for white matter stroke.

Distributed Arrays of Small Instruments (NSF)

Federal Grants & ContractsVolume 43, Issue 4 p. 1-1 Grants Alerts Distributed Arrays of Small Instruments (NSF) First published: 15 January 2019 https://doi.org/10.1002/fgc.30211Read the full textAboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinkedInRedditWechat No abstract is available for this article. Volume43, Issue417 January 2019Pages 1-1 RelatedInformation

Ozonesonde Quality Assurance: The JOSIE-SHADOZ (2017) Experience.

The ozonesonde is a small balloon-borne instrument that is attached to a standard radiosonde to measure profiles of ozone from the surface to 35 km with ~100-m vertical resolution. Ozonesonde data constitute a mainstay of satellite calibration and are used for climatologies and analysis of trends, especially in the lower stratosphere where satellites are most uncertain. The electrochemical-concentration cell (ECC) ozonesonde has been deployed at ~100 stations worldwide since the 1960s, with changes over time in manufacture and procedures, including details of the cell chemical solution and data processing. As a consequence, there are biases among different stations and discontinuities in profile time-series from individual site records. For 22 years the Jülich [Germany] Ozone Sonde Intercomparison Experiment (JOSIE) has periodically tested ozonesondes in a simulation chamber designated the World Calibration Centre for Ozonesondes (WCCOS) by WMO. In October-November 2017 a JOSIE campaign evaluated the sondes and procedures used in SHADOZ (Southern Hemisphere Additional Ozonesondes), a 14-station sonde network operating in the tropics and subtropics. A distinctive feature of the 2017 JOSIE was that the tests were conducted by operators from eight SHADOZ stations. Experimental protocols for the SHADOZ sonde configurations, which represent most of those in use today, are described, along with preliminary results. SHADOZ stations that follow WMO-recommended protocols record total ozone within 3% of the JOSIE reference instrument. These results and prior JOSIEs demonstrate that regular testing is essential to maintain best practices in ozonesonde operations and to ensure high-quality data for the satellite and ozone assessment communities.

Association of circulating 25-hydroxyvitamin D levels with hypertension and blood pressure values in Korean adults: A Mendelian randomization study on a subset of the Korea National Health and Nutrition Survey 2011-2012 population.

BACKGROUND/OBJECTIVESLower circulating 25-hydroxyvitamin D [25(OH)D] levels are associated with a higher risk of hypertension (HTN); however, it remains unclear whether the relationship is causal. We aimed to evaluate the causal effects of circulating 25(OH)D levels on the prevalence of HTN in the Korean population using the Mendelian randomization (MR) approach.SUBJECTS/METHODSEpidemiological data, serum 25(OH)D data, and genomic DNA biospecimens were obtained from 2,591 participants, a subset of the study population in the Korea National Health and Nutrition Survey 2011-2012. Five 25(OH)D-related single nucleotide polymorphisms (SNPs; DHCR7 rs12785878, CYP2R1 rs10741657, CYP2R1 rs12794714, CYP24A1 rs6013897, and GC rs2282679), identified a priori from genome-wide association studies, were used as instrument variables (IVs) for serum 25(OH)D levels. In the MR analysis, we performed IV analyses using the two-stage least squares method.RESULTSIn the observational analysis, circulating 25(OH)D levels were found to be inversely associated with the HTN prevalence in ordinary least squares models (odds ratio: 0.97, 95% confidence interval: 0.96, 0.99) after adjusting for the potential confounders. There were differences in the circulating 25(OH)D levels across genotypes of individual SNPs. In the MR analysis, using individual SNPs as IVs, 25(OH)D levels were not associated with the HTN prevalence.CONCLUSIONSWe found no association between genetically determined circulating 25(OH)D levels and HTN in Korean adults. Our results are listed owing to the relatively small sample size and possible weak instrument bias; therefore, further studies are needed to confirm these results.

Fully Integrated Liquid-Core Waveguide Fluorescence Lifetime Detection Microsystem for DNA Biosensing

Time-resolved fluorescence is a widely adopted technique for DNA detection due to its high sensitivity and selectivity. However, due to stringent requirements on optics and electronics, instrumentation with time-resolved capability is bulky and expensive, prohibiting their use in portable and point-of-care applications. In this work, a fully-integrated DNA biosensor based on liquid-core waveguide (LCW) optics for fluorescence lifetime analysis is presented. The DNA biosensor encompasses all-custom bioassay, optics and electronics into a microsystem, delivering a near sample-to-answer level of integration. Lifetime, rather than intensity, is exploited as the analytical signal from the V-carbazole probe for the first time. Excitation propagation within the LCW is investigated both analytically and in simulations to achieve high excitation rejection and low temporal dispersion, enabling the proposed LCW-based system with much smaller instrumentation size to deliver comparable lifetime measurement accuracy to traditional systems. Detection of DNA down to 15 base pairs at a low detection limit of 1.38 nM demonstrates the high applicability of the proposed biosensor for compact, application-specific, and low-cost diagnostics devices.

Rapid and sensitive label-free determination of aflatoxin M1 levels in milk through a White Light Reflectance Spectroscopy immunosensor

A miniaturized optical immunosensor based on White Light Reflectance Spectroscopy (WLRS) for the rapid and label-free detection of aflatoxin M1 (AFM1) in milk samples has been developed. WLRS sensing system consists of the measurement set-up and the biochip. The first encompasses the reflection probe, the light source and the spectrometer, while the latter is a Si chip with a SiO2 layer on top where an AFM1-bovine serum albumin conjugate has been immobilized. The assay was performed by running mixtures of rabbit polyclonal anti-AFM1 antibody with the calibrators or the samples, followed by reaction with biotinylated anti-rabbit IgG antibody and streptavidin. The assay cycle was completed in 25 min, the limit of detection was 6 pg/mL, and the linear working range extended from 0.012 to 2.0 ng/mL. The assay was repeatable (intra-and inter-assay coefficients of variation ranged from 2.1 to 6.3% and 3.5 to 8.2%, respectively) and accurate (percent recovery values ranged from 92.5 to 110%). AFM1 could be detected with the immunosensor developed in both processed and unprocessed milk of different animal species without any dilution. The excellent analytical characteristics and the small instrument size make the proposed sensor suitable for accurate low-cost AFM1 determination in milk samples at the point-of-need.

Rapid detection method and portable device based on the photothermal effect of gold nanoparticles

Gold nanoparticle (GNP)-labeled immunochromatography test strip (ICTS) has been widely used in different fields, but its sensitivity still require further improvement. In this work, a rapid and quantitative test strip detection method based on the photothermal effect of GNPs was established using a temperature sensor. A portable sensor device was fabricated based on the above method, and the main operating parameters were optimized. Three types of analyte models (cells, macromolecules, and small molecules) were chosen to evaluate the application of the sensor device using the commercial ICTS. The detection limit is at least 1 order of magnitude lower than that of the traditional visual detection ICTS. The other strip type of dot immunogold filtration test was adopted to further improve the sensitivity. The sensitivity of the sensor detection method was similar to that of the infrared camera method, and the proposed sensor device has obvious advantage of low-cost, as well as the usage of a small portable instrument, ease of use and rapid test. The portable sensor device based on the photothermal effect of GNPs can be used as a new and promising device for simple, quantitative, rapid, and on-site screening of analyte by ICTS.

Comparing postoperative complication of LigaSure Small Jaw instrument with clamp and tie method in thyroidectomy patients: a randomized controlled trial [IRCT2014010516077N1

BackgroundLigaSure® Small Jaw (LSJ) has been recently introduced as an energy-based vessel sealing device, which has provided better intraoperative and postoperative outcomes in thyroidectomies, compared to conventional technique. In the current study, we aimed to examine the efficiency of hand-sewn and LSJ thyroidectomy, based on operation time and perioperative complications.MethodsAll patients with the diagnosis of multinodular goiter, thyroid cancers, retrosternal goiter and other indications for thyroid surgeries, enrolled. Of 550 patients, 261 patients randomly assigned to the conventional group (A) and 274 patients to LigaSure Small Jaw group (B). Study groups compared concerning operative time, recurrent laryngeal nerve (RLN) injury, hypocalcemia, and postoperative complications.ResultsThere was no significant difference regarding demographic data between groups A and B. During total thyroidectomy, intraoperative blood loss was 64.42 ± 20.72 ml and 49.64 ± 17.92 ml in groups A and B, respectively (P 0.043). Operative time was significantly lower in LSJ group compared to the conventional group in total and subtotal thyroidectomy (P 0.002; P 0.001). Three patients who underwent conventional total thyroidectomy had RLN palsy. However, there was no significant difference between techniques regarding RLN injury (P 0.134).Postoperative total and ionized serum calcium levels decreased compared to preoperative levels in both conventional and LSJ technique; however, changes in total and ionized serum calcium were more severe in patients with conventional thyroidectomy (total calcium, P < 0.0001) (ionized calcium, P 0.005).ConclusionThe LigaSure Small Jaw device decreases operative time and intraoperative bleeding compared to conventional technique. Besides, changes in total and ionized calcium levels in patients with LSJ thyroidectomy are subtle compared to HS technique.Trial registrationRegistered in Iranian Registry of Clinical Trials (www.irct.com), trial registration: IRCT2014010516077N1, Registered: 23 May 2014).

Diagnosing intellectual disability: detecting big concerns with small instruments.

This commentary is on the original article by McKenzie et al. on pages 444–450 of this issue.

Liquid-Infused Surfaces on Electrosurgical Instruments with Exceptional Antiadhesion and Low-Damage Performances.

Electrosurgery based on electrosurgical instruments plays an important role in clinical surgery owing to its advantages of ease of operation, low damage, and less pain to the patient. But soft tissue adhesion on electrosurgical instruments is still a major obstacle to improve the operation efficiency and achieve a better surgical result, regardless of so many developed methods to enhance the antiadhesion performance. In this paper, we successfully demonstrated that liquid-infused surfaces (LISs) can significantly improve the antiadhesion performance of electrosurgical instruments. We developed a microcontact printing method to assist the structure fabrication on the small instrument tip to prepare a firmly liquid-held surface. Soft tissue cutting experiments showed that LIS could not only significantly reduce the adhesion force between the tissue and the instrument tip but also lead to a much smaller charring wound. The underlying mechanism was discussed, and further experiments concluded that LIS have a better duration capability. Our study provides a new insight into the antiadhesion design for electrosurgical instruments.