Instrument Size Research Articles

Recent developments in microfluidic passive separation to enable purification of platelets for transfusion

Platelet transfusion is a lifesaving therapy intended to prevent and treat bleeding. However, in addition to platelets, a typical unit also contains a large volume of supernatant that accumulates multiple pro-inflammatory contaminants, including residual leukocytes, microaggregates, microparticles, antibodies, and cytokines. Infusion of this supernatant is responsible for virtually all adverse reactions to platelet transfusions. Conventional methods for removing residual leukocytes (leukoreduction) and reducing the volume of transfused supernatant (volume reduction) struggle to mitigate these risks holistically. Leukoreduction filters can remove leukocytes and microaggregates but fail to reduce supernatant volume, whereas centrifugation can reduce volume, but it is ineffective against larger contaminants and damages platelets. Additionally, platelet purification based on these methods is often too logistically complex, time-consuming, and labor-intensive to implement routinely. Emerging microfluidic technologies offer promising alternatives through passive separation mechanisms that enable cell separation with minimal damage and drastically reduced instrumentation size and facility requirements. This review examines recent innovations in microfluidic cell separation that can be used for leukoreduction and volume reduction of platelets. It begins by defining the performance requirements that any separation method must meet to successfully replace conventional methods currently used to perform these tasks. Standard performance metrics are described, including leukocyte depletion efficiency, degree of volume reduction, processing throughput, and platelet recovery. Finally, the review outlines the primary challenges that must be overcome to enable simple-to-use, disposable microfluidic devices capable of both reducing the platelet unit volume and removing pro-inflammatory contaminants, while preserving most functional platelets for transfusion.

Intracanal antibacterial effects of a bioceramic medication compared with calcium hydroxide pastes in different vehicles

The intracanal antibacterial effectiveness of a bioceramic medication was compared with calcium hydroxide pastes in different vehicles. Extracted mandibular incisors with a single long oval canal were selected and distributed into 5 groups based on anatomically paired micro-computed tomographic analyses. The root canals were prepared up to an instrument size 35/04 and contaminated for 30 days with a mixed bacterial culture from subgingival biofilm added with Enterococcus faecalis. The canals were medicated with Bio-C Temp (Angelus Indústria de Produtos Odontológicos, Londrina, PR, Brazil) or a calcium hydroxide paste in glycerin (CHG), camphorated paramonochlorophenol/ glycerin (CHPG), or 2% chlorhexidine (CHCX). Control specimens were filled with sterile saline. After 7 days, the medication was removed by using rotary instruments and saline irrigation. A supplementary approach was conducted, which consisted of 2.5% NaOCl irrigation and agitation with XP-endo Finisher. Bacteriological samples were taken before application (S1) and after removal (S2) of the intracanal medication, and after the supplementary approach (S3). Bacterial DNA extracted from the samples was quantified using real-time polymerase chain reaction. Bacterial counts were significantly reduced from S1 to S2 in all groups, except for the control group. As for S1-to-S3 changes, all groups (control included) showed significant bacterial reduction. S2-to-S3 changes were only significant in the CHPG and CHCX groups (p<0.05). Intergroup comparisons showed no significant differences in S2 (p>0.05), with all medications significantly better than the control (p<0.05). In S3, only the CHPG and CHCX groups showed further significant bacterial reductions. Categorical data analysis showed no intergroup differences (p>0.05). All tested medications significantly reduced the intracanal bacterial counts, with no significant differences between them. Final NaOCl irrigation and agitation using XP-endo Finisher further enhanced disinfection in the CHCX and CHPG groups.

Experimental Center El Remanso ECER in Choachi-Colombia. A Laboratory Eco-Village to Learn and Co-build a Circular Learning

AbstractThe purpose of this article was to show the progress in the implementation of an Eco-Village that incorporated elements of bioconstruction with the use of bamboo-guadua cane framed in a circular design and integrated planning approaches for the increasing resilience in an area of high seismic risk in the Colombian Andes Mountains. Likewise, it included energy transition elements advancing towards decarbonization with the use of solar panels for electricity generation and water heating. At the same time, it integrated clean production linked to regenerative agriculture and circular bioeconomy using closed water circuits from bioprospection purification processes in internal treatment plants, equally, waterless toilets that allow the use of human waste as an input for composting and urine mixed with water for nitrogen fixation in permaculture gardens. Likewise, Experimental Center El Remanso ECER has allowed the application of Interdisciplinary education related to Ecological Engineering Education. The project is framed in the concepts and theories of bioeconomy and degrowth (Georgescu-Roegen, Latouche). An exploratory qualitative methodology was considered based on the participatory action research PAR proposals of Fals Borda. In addition to, the meeting with the traditional knowledge of the indigenous people and the peasant communities of the area in the production and cooking of food and the recovery of soils and ecosystems, as well as, the implementation of associativity processes related to the design and execution of tourist routes. As result of the research, the importance of co-creation, respect for ancestral knowledgement and the dialogue of knowledges are recognized, among others. The used of the small sample size of the different information access instruments were recognized as a limitation in the research. However, future actions linked to the results of the implementation of the PAR are been planned.

Compact, high-resolution spectrometers with grating–metasurface coupling for CO2 detection

Off-axis reflective optical systems are commonly used to minimize the dimensions of spectrometers. However, despite sophisticated off-axis reflective designs, constructing systems with excellent spectral and spatial resolutions, particularly those that can be used for CO2 gas detection in space-based spectrometers, necessitates maintaining a significant overall instrument size. The metasurface is an innovative optical device that can enable spectrometer miniaturization. For CO2 spectral detection in the near-infrared spectral range of 1590–1620 nm, this study proposes a device that integrates a grating with a metasurface for off-axis convergence within the relevant wavelength range. The grating facilitates primary spectral dispersion, whereas the metasurface enables off-axis convergence at different wavelengths. Grating–metasurface coupling effectively enhances the spectral resolution of the spectrometer, mitigating any efficiency losses caused by excessive off-axis angles. The proposed strategy exhibits high potential for on-chip integrated photonics and the fabrication of small-size spaceborne spectrometers.

Lord of the (Magnetic) Rings: Rigid Bronchoscopy for Aspirated Magnetic Foreign Bodies in Tertiary Bronchi

ObjectivesTo describe operative techniques using rigid bronchoscopy and ferromagnetic bronchoscopic equipment to retrieve magnetic foreign bodies in distal tertiary bronchi beyond the reach of traditional optical instrumentation.MethodsA 13‐year‐old presented to the Emergency Department following aspiration of three backing magnets from a magnetic nose ring. Chest radiographs demonstrated a 4 mm × 3 mm foreign body in the right lower lobe 0.5 cm from diaphragm on expiratory film. She was taken to the operating room for removal of an airway foreign body.ResultsThe foreign body was visualized with direct laryngoscopy followed by rigid bronchoscopy in the distal right lower tertiary bronchus. Attempts to pass optical instruments were limited both by distance of the object and size of instrumentation compared to the diameter of the tertiary bronchus. A salivary wire basket and ureteral stone retrieval basket were then passed with endoscopic visualization into the tertiary bronchus but were unable to engage the foreign body. An attempt was made to pass a 2 French Fogarty embolectomy catheter distally, but the catheter was too large to bypass the foreign body. Finally, ferromagnetic pulmonary rat tooth biopsy forceps were advanced into the tertiary bronchus and successfully attracted the magnetic foreign body for safe removal through our rigid bronchoscope.ConclusionWe present a novel method of utilizing ferromagnetic flexible bronchoscopic instruments to safely remove magnetic foreign bodies in the tertiary bronchi beyond the reach of traditional bronchoscopic instruments. Laryngoscope, 2024

Chromatic focus variation microscopy for surface metrology

Optical metrology plays a vital role in a wide range of research and inspection areas in the industry. At present, the market offers a variety of optical metrology instruments, among which the focus variation microscope stands out for its capability of measuring steep surfaces with high slopes. The traditional focus variation (FV) instrument mechanically scans the surface by sweeping the focal plane of the objective lens using linear motion stages and simultaneously capturing images at different scanning positions, forming a stack of images. The mechanical motion stages require regular maintenance and calibration to ensure accuracy over time. Another issue associated with the mechanical scanning methods is their physical size, which creates a limiting factor to compactness for in-situ measurement applications. This work proposes a chromatic focus variation (CFV) method that replaces mechanical scanning with a wavelength scanning mechanism to overcome the above limitations. Unlike traditional focus variation, the CFV system employs a dispersive objective lens (i.e. chromatically aberrated objective lens) to axially shift the focus along the optical axis to provide vertical/depth scanning. This approach brings significant enhancements in measurement speed and reduces the instrument size for on-machine metrology tasks. In this paper, a detailed analysis of the optical performance of the dispersive objective lens is conducted, and then the measurement performance of the proposed CFV system is validated using samples including a step height of 30 µm and a sine wave shape with a peak-to-valley amplitude of 19 µm. The experiment results were compared to those from the state-of-the-art commercial instrument (Alicona G5), which showed a good agreement between the two. Furthermore, a detailed analysis and discussions are provided to investigate the measurement’s accuracy.

Value of ultrathin bronchoscope in improving the endobronchial ultrasound localization rate and diagnosing peripheral pulmonary nodules by cryobiopsy

BackgroundA 3.0-mm ultrathin bronchoscope (UTB) with a 1.7-mm working channel provides better accessibility to peripheral bronchi. A 4.0-mm thin bronchoscope with a larger 2.0-mm working channel facilitates the use of a guide sheath (GS), ensuring repeated sampling from the same location. The 1.1-mm ultrathin cryoprobe has a smaller diameter, overcoming the limitation of the size of biopsy instruments used with UTB. In this study, we compared the endobronchial ultrasound localization rate and diagnostic yield of peripheral lung lesions by cryobiopsy using UTB and thin bronchoscopy combined with GS.MethodsWe retrospectively evaluated 133 patients with peripheral pulmonary lesions with a diameter less than 30 mm who underwent bronchoscopy with either thin bronchoscope or UTB from May 2019 to May 2023. A 3.0-mm UTB combined with rEBUS was used in the UTB group, whereas a 4.0-mm thin bronchoscope combined with rEBUS and GS was used for the thin bronchoscope group. A 1.1-mm ultrathin cryoprobe was used for cryobiopsy in the two groups.ResultsAmong the 133 patients, peripheral pulmonary nodules in 85 subjects were visualized using r-EBUS. The ultrasound localization rate was significantly higher in the UTB group than in the thin bronchoscope group (96.0% vs. 44.6%, respectively; P < 0.001). The diagnostic yield of cryobiopsy specimens from the UTB group was significantly higher compared to the thin bronchoscope group (54.0% vs. 30.1%, respectively; p = 0.006). Univariate analysis demonstrated that the cryobiopsy diagnostic yields of the UTB group were significantly higher for lesions ≤ 20 mm, benign lesions, upper lobe lesions, lesions located lateral one-third from the hilum, and lesions without bronchus sign.ConclusionsUltrathin bronchoscopy combined with cryobiopsy has a superior ultrasound localization rate and diagnostic yield compared to a combination of cryobiopsy and thin bronchoscopy.

Euclid. III. The NISP instrument

The Near-Infrared Spectrometer and Photometer (NISP) on board the satellite provides multiband photometry and $R slitless grism spectroscopy in the 950--2020\,nm wavelength range. In this reference article, we illuminate the background of NISP's functional and calibration requirements, describe the instrument's integral components, and provide all its key properties. We also sketch the processes needed to understand how NISP operates and is calibrated as well as its technical potentials and limitations. Links to articles providing more details and the technical background are included. The NISP's 16 H2RG detectors with a plate scale of $ deliver a field of view of 0.57\,deg$^2$. In photometric mode, NISP reaches a limiting magnitude of sim \,24.5\,AB\,mag in three photometric exposures of about 100\,s in exposure time for point sources and with a S/N of five. For spectroscopy, NISP's point-source sensitivity is a SNR = 3.5 detection of an emission line with flux sim \,$2 $ integrated over two resolution elements of 13.4\ in 3times 560\,s grism exposures at 1.6\ (redshifted Halpha ). Our calibration includes on-ground and in-flight characterisation and monitoring of the pixel-based detector baseline, dark current, non-linearity, and sensitivity to guarantee a relative photometric accuracy better than 1.5&lt;!PCT!&gt; and a relative spectrophotometry better than 0.7&lt;!PCT!&gt;. The wavelength calibration must be accurate to 5\ or better. The NISP is the state-of-the-art instrument in the near-infrared for all science beyond small areas available from HST and JWST -- and it represents an enormous advance from any existing instrumentation due to its combination of field size and high throughput of telescope and instrument. During six-year survey covering 14\,000\,deg$^2$ of extragalactic sky, NISP will be the backbone in determining distances of more than a billion galaxies. Its near-infrared data will become a rich reference imaging and spectroscopy data set for the coming decades.

Effects of increasing instrument size and taper on the disinfection and shaping of mandibular incisors.

This study assessed canal preparation effects on disinfection and dentin preservation. Thirty mandibular incisors were paired into two experimental groups (n = 10). Following contamination, the initial microbial sample was collected. Instruments 30/0.03 (Group 1) and 30/0.05 (Group 2) were employed and a second sample was obtained. Canals were enlarged using instruments 40/0.03 and 40/0.05, respectively, and a third sample was collected. Final irrigation was performed, and sample S4 obtained. A final scan evaluated volume, surface area, unprepared areas, removed dentin and dentin thickness. Data were analysed using Student t-test, Mann-Whitney, Kruskal-Wallis and Dunn tests. A significant difference was observed between S1 and other time points (p < 0.05). Comparison between groups showed no differences in bacterial loads and in the percentage of microbial reduction (p > 0.05). Group 2 exhibited greater reduction in dentin thickness than group 1 in the mesial aspect of the root (p < 0.05). Instrument 30/0.03 might provide effective disinfection and safety during mandibular incisors canal preparation.

Dynamic Photoelastic Analysis of Stress Distribution in Simulated Canals Using Rotary Instruments with Varied Tip and Taper Sizes: A Quasi-3D Approach

IntroductionTo compare the stress produced on the walls of simulated canals by rotary instruments with varied tip and taper sizes. MethodsNinety isotropic transparent blocks, each containing a 60-degree curved canal, were distributed into 18 groups (n = 5) based on the instrument tip (sizes 10, 15, 20, 25, 30, and 35) and taper (sizes 0.02, 0.04, and 0.06). The blocks were fixed in a circular polariscope setup for dark field analysis. A digital camera was employed to capture the real-time birefringence patterns generated by each instrument. Digital image frames, corresponding to the instrument reaching the end of each canal third, were extracted and evaluated by 2 independent observers for the stress generation on canal walls. The data analysis employed a semi-quantitative scale ranging from 0 to 5. Cohen's Kappa coefficient test was used to determine the inter-observer agreement while the results were compared using Kruskal–Wallis test followed by an all-pairwise posthoc procedure (α = 5%). ResultsInter-observer agreement was 0.95. A significant influence of the tip size on stress was observed across the coronal (P = .011), middle (P = .006), and apical (P = .026) thirds. In contrast, taper size did not affect the stress induced at the coronal (P = .509), middle (P = .958), or apical (P = .493) thirds. The variations in tip and taper sizes did not result in a significant stress differences among the thirds (P = .181). ConclusionsThe stress significantly increased across all canal thirds with larger tip sizes of rotary instruments, whereas the taper sizes did not influence the stress when compared to the canal thirds.

Camera sheath with transformable head for minimally invasive surgical instruments

Introduction This paper presents a camera sheath that can be assembled to various minimally invasive surgical instruments and provide the localized view of the instrument tip. Material and methods The advanced transformable head structure (ATHS) that overcomes the trade-off between the camera resolution and the instrument size is designed for the sheath. Design solutions to maintain the alignment between the camera’s line of sight and the instrument tip direction during the transformation of the ATHS are derived and applied to the prototype of the sheath. Results The design solution ensured proper alignment between the line of sight and the tip direction. The prototype was used with the curved micro-debrider blades in simulated functional endoscopic sinus surgery (FESS). Deep regions of the sinus that were not observable with the conventional endoscopes was accessed and observed using the prototype. Conclusions The presented camera sheath allows the delivery of the instrument and camera to the surgical site with minimal increase in port size. It may be applied to various surgeries to reduce invasiveness and provide additional visual information to the surgeons.

Smartphone-Integrated Wireless Portable Potentiostat to Develop 5th-Generation Dengue Pocket Aptasensor toward Portronicx-Approach.

Smartphones' widespread availability and worldwide connection are advancing the idea of mobile-based healthcare and promise to transform the business of biosensors. Biosensors based on smartphones have been investigated in several ways, including employing a smartphone in place of a detector or as an instrumental interface. The current work demonstrates the first successful detection of dengue virus using a smartphone-based pocket sensor combined with a wireless potentiostat. The platform developed comprises a smartphone, a wireless portable potentiostat, an Android app, and a three-electrode setup. The combination of portable diagnostic with electronic application is referred to as "Portronicx", and this is the first time that the term "Portronicx" has been used in a dengue sensor, so the current study has the potential to be commercialized in the market with the tag line "Portronicx-commercialization" in the future. Miniaturization improves alternative setup options in terms of instrument size, affordability, mobility, touch-mobile display, and design versatility. The current work proved the excellent combination of a wireless potentiostat with an aptasensor to detect dengue antigen within 20 s with good LOD (0.1 μg/mL) and easy to carry in their pockets. The created platform also performed effectively in human serum. This study replaced all of the instruments with a lightweight touch smartphone, paving the way for the production of fifth-generation electrochemical aptasensors, with potential implications for healthcare applications on the verge of commercialization.

Marine soundscape monitoring from underwater autonomous vehicles—Passive acoustic monitoring gliders

Ocean gliders are buoyancy-driven autonomous underwater platforms, able to collect oceanographic measurements along vertical profiles during multi-months missions, covering thousands of kilometers. They glide quietly through the water column without propulsion noise and are therefore extremely suitable for Passive Acoustic Monitoring (PAM) of the marine environment. From PAM glider data in the Mediterranean Sea and the Southern Ocean, we illustrate the current and potential uses of PAM gliders for the study of physical oceanography, biology, ecology and for regulatory purposes. We evaluate limiting factors for PAM glider survey, such as platform-generated and flow noise, instrument size and power constraints, profiling ability and movement of the platform. We provide recommendations and good practices for typical PAM glider surveys and present future developments identified by the PAM glider community to further develop the readiness level and societal impact of PAM glider observation: (1) Calibration of the PAM glider to collect absolute sound levels; (2) adapted sampling methods and statistical analysis techniques to perform population density estimation; and (3) Integration of PAM glider observation to existing monitoring programs.

A portable frequency‐domain electromagnetic detection system

SummaryFrequency‐domain detection stands as a critical method in remote geophysical exploration; however, its practical application is constrained by the considerable size of the requisite instrumentation. In this paper, we present a compact frequency domain electromagnetic detection system. The integration of intelligent power devices and a novel hardware architecture substantially diminishes the system's dimensions, thereby enhancing its portability. Furthermore, the system design incorporates sinusoidal pulse width modulation and digital phase‐locked amplification to ensure the efficacy of the proposed system. Both the transmitter and receiver system are constrained to dimensions smaller than 1.5 m. Subsequent experimental validation attests to the exemplary hardware performance of the proposed system, with the transmitting voltage of the transmitter circuit attaining 500 V, and the receiver circuit exhibiting a sensitivity as low as 10−8 V. Significantly, this design paradigm not only facilitates the integration of transmitter and receiver systems for frequency‐domain electromagnetic detection but also introduces novel prospects for the application of frequency‐domain electromagnetic detection methods across diverse fields.

Soft Tissue Robotic Assisted Orbital Surgery Using da Vinci SP: A Cadaveric Experience.

Robotic surgical techniques have transformed many surgical specialties however robotic techniques and applications have been much more limited in ophthalmology. This study aims to evaluate the feasibility of robotic assisted orbital surgery using a single-port novel robotic platform, the da Vinci SP. A series of orbital procedures were performed in cadaveric specimens utilizing the da Vinci SP robotic system. The procedures performed included lacrimal gland dissection and biopsy, medial and lateral orbital wall dissections, enucleation, and lid-sparing orbital exenteration. Successful completion of each procedure was defined by the operating surgeon and was considered the primary outcome and marker of feasibility. Seven cadaveric procedures were performed in 3 cadaveric specimens. All 7 procedures were completed successfully without complication. Setup optimization occurred throughout the study and setup and operative times were acceptable. Three instrument arms and 1 endoscope were utilized throughout the study allowing 3 arm operating and dynamic retraction. Instrument size was found to limit surgical access and precision particular at the orbital apex. This preclinical study demonstrates that the da Vinci SP can be utilized within the orbit and is feasible for several applications. Robotic surgical systems offer significant advantages over conventional techniques and should be embraced. However, current commercially available robotic platforms are not optimized for the orbit and have their limitations although they may be suitable for some clinical applications.

Cavity preparation model in rat maxillary first molars: A pilot study

Objective: To conduct a standardized method for cavity preparation on the palatal surface of rat maxillary molars and to introduce a standardized method for tooth correct alignment within the specimen during the wax embedding procedure to better detect cavity position within the examined slides. Materials and methods: Six male Wistar rats, aged 4-6 weeks, were used. The maxillary molars of three animals were sectioned in the frontal plane to identify the thickness of hard tissue on the palatal surface of the first molar which was (250-300µm). The end-cutting bur (with a cutting head diameter of 0.2mm) was suitable for preparing a dentinal cavity (70-80µm) depth. Cavity preparation was then performed using the same bur on the tooth surface in the other three animals. Rats are then euthanized before dissecting, fixing, and demineralizing the teeth. For better alignment of teeth samples during the waxing procedure, K-file endodontic instrument size #8 was dipped in Indian ink. The file tip was inserted on the jaw bone at the buccal side of the tooth in a region opposed to the prepared cavity on the palatal side. Moreover, a small Dycal applicator instrument was used to mark the jaw bone on the mesial side of teeth samples as an orientation for the cutting surface. Results: Well-defined sections were obtained with a clear cavity extension within dentin and without any signs of pulp exposure in all samples. Conclusion: This pilot was conducted to perform an easy procedure for cavity preparation in rat molar teeth to obtain a clear histopathological section.

A comparative study of the cutting efficiency of diamond rotary instruments with different grit sizes with a low-speed electric handpiece against zirconia specimens

The use of zirconia in dentistry has increased. However, little attention has been given to the difficulty experienced by clinicians when cutting zirconia restorations intraorally. Evidence for which grit size and type of rotary instrument is best for cutting zirconia intraorally is lacking. The purpose of this in vitro study was to identify the most efficient diamond rotary instrument grit size for cutting zirconia intraorally. Efficiency was measured by comparing the cutting depth of each rotary instrument into zirconia, analyzing zirconia specimens for surface damage after cutting, and measuring instrument deterioration. Thirty zirconia specimens of the same measurements were used as test specimens and cut with 30 diamond rotary instruments with different grit sizes. An electric handpiece was used with constant force (1.7N), speed (40 000rpm), time (1min), and water flow rate (25mL/min) to produce comparative data. The mean cutting efficiency values were compared by analysis, and the median values were compared by the nonparametric Kruskal-Wallis test (α=.05). Each test was followed up with pair wise comparisons of the mean or median values if significance was indicated. The greatest cutting depth was achieved with a fine-grit instrument with a mean cutting depth of 5.79mm compared with 4.54mm for the coarse-grit instrument (P=.032). The greatest damage to zirconia was done by the coarse- and supercoarse-grit instruments (both 33%), with no substrate damage by the superfine-, fine-, and medium-grit instruments. The greatest instrument deterioration was found on the supercoarse rotary instruments (9.05%). With only 3 exceptions, the power calculations were all sufficient and above 83%. The fine grit rotary instrument (between 40 and 50µm) was the most efficient, achieving the greatest cutting depth, with no detectable macroscopic damage to the zirconia and minimal instrument deterioration.

Female Surgical Ergonomics in Otolaryngology: A National Survey Study.

To assess the nature and impact surgical ergonomic challenges experienced by female otolaryngologists. National survey study. Female otolaryngology residents, fellows and attendings recruited via social media posting and email distribution. We distributed a survey study to female otolaryngologists throughout the United States. The height and glove size of participants reporting difficulties with equipment and instruments were compared to those not reporting difficulties. Ninety-six female otolaryngologists participated in our study, comprised of 43% residents, 10% fellows, and 47% attendings. Ninety percent of participants reported difficulties using equipment and 77% of participants reported difficulty with instruments, the most common being nasal endoscopic instruments (28%). The vast majority of participants reported pain during and (or) after the operation (92%). Head and neck (53%) and rhinology (44%) were identified as particularly challenging specialities, but only 25% of participants reported that ergonomics affected their career plans. Participants felt that adjustable equipment (60%), a variety of sizes of instruments (43%), and more discussion around ergonomics (47%) would help. Respondents reported adjusting the operating room to accommodate their size took extra time (44%) and was a mental burden (39%). Participants reporting difficulties with operating room equipment were significantly shorter than those without difficulties (64 inches vs 67 inches, P = .037), and those reporting difficulties with instruments had a smaller median glove size (6 vs 6.5, P = .018). Surgical ergonomics represent a challenge for female otolaryngologists, particularly those with smaller hands and shorter height. Partnering with industry, we must address the needs of an increasingly diverse workforce to ensure that all surgeons can operate effectively and comfortably.

Unlocking ultimate precision of intensity and area ratio measurements in Raman spectroscopy: Insights from simulation, experimentation, and theory and implications for isotope ratio analysis

AbstractThe intensity ratio (αI) and area ratio (αA) obtained using Raman spectroscopy are used widely to characterize the physical properties of gases, fluids, and solids, but the underlying parameters which affect their precision ( and ) have not been elucidated. We use simulations, experiments, and theoretical analyses to investigate the effects of instrumental performance, analytical conditions, and sample size on and . We identified the parameters which strongly influence : (1) the weaker peak intensity Iw; (2) the ratio of the bandwidth to pixel resolution of the weaker peak Γw/Δxw; (3) the degree of detector saturation; (4) with readout noise σR, dark noise σD, and shot noise σS; (5) drift; and (6) sample size. Theoretical and simulation results show that, when Γw/Δxw ≪ (Γs/Δxs)/αI, increasing Iw or Γw/Δxw by n times can improve by a factor of . Results showed that is a measure of how much the achievable in the experiment differs from that under ideal analytical conditions (i.e., ). When is not the case (i.e., when Iw is low), reducing σD or σR by decreasing the readout speed, setting a lower charge coupled device (CCD) sensitivity, reducing number of readouts, or narrowing vertical binning width can improve . We demonstrated that evaluations of or based on small sample sizes can engender physically unattainable precision. When the sample size is n = 5, 10, or 20, the average uncertainties of and correspond, respectively, to approximately 30%, 20%, and 15%. Giving an accurate and comparable assessment for and necessitates the reporting of intensity (in units of electrons), bandwidth, Δx, and the sample size.

Simultaneous Detection of SARS-CoV-2 Nucleoprotein and Receptor Binding Domain by a Multi-Area Reflectance Spectroscopy Sensor.

The COVID-19 pandemic has emphasized the urgent need for point-of-care methods suitable for the rapid and reliable diagnosis of viral infections. To address this demand, we report the rapid, label-free simultaneous determination of two SARS-CoV-2 proteins, namely, the nucleoprotein and the receptor binding domain peptide of S1 protein, by implementing a bioanalytical device based on Multi Area Reflectance Spectroscopy. Simultaneous detection of these two proteins is achieved by using silicon chips with adjacent areas of different silicon dioxide thickness on top, each of which is modified with an antibody specific to either the nucleoprotein or the receptor binding domain of SARS-CoV-2. Both areas were illuminated by a single probe that also collected the reflected light, directing it to a spectrometer. The online conversion of the combined reflection spectra from the two silicon dioxide areas into the respective adlayer thickness enabled real-time monitoring of immunoreactions taking place on the two areas. Several antibodies have been tested to define the pair, providing the higher specific signal following a non-competitive immunoassay format. Biotinylated secondary antibodies and streptavidin were used to enhance the specific signal. Both proteins were detected in less than 12 min, with detection limits of 1.0 ng/mL. The assays demonstrated high repeatability with intra- and inter-assay coefficients of variation lower than 10%. Moreover, the recovery of both proteins from spiked samples prepared in extraction buffer from a commercial self-test kit for SARS-CoV-2 collection from nasopharyngeal swabs ranged from 90.0 to 110%. The short assay duration in combination with the excellent analytical performance and the compact instrument size render the proposed device and assay suitable for point-of-care applications.