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Introduction The main goal of this study was to assess the feasibility of a head-mounted display (HMD) providing telemedicine neurosurgical support during a decompressive craniectomy by a military surgeon who is isolated from readily available neurosurgical care. The secondary aim was to assess the usability perceived by the military surgeon and to evaluate technical aspects of the head-mounted display. Materials and Methods After a standard concise lecture, 10 military surgeons performed a decompressive craniectomy on a AnubiFiX-embalmed post-mortem human head. Seven military surgeons used a HMD to receive telemedicine neurosurgical support. In the control group, three military surgeons performed a decompressive craniectomy without guidance. The performance of the decompressive craniectomy was evaluated qualitatively by the supervising neurosurgeon and quantified with the surgeons' operative performance tool. The military surgeons rated the usability of the HMD with the telehealth usability questionnaire. Results All military surgeons performed a decompressive craniectomy adequately directly after a standard concise lecture. The HMD was used to discuss potential errors and reconfirmed essential steps. The military surgeons were very satisfied with the HMD providing telemedicine neurosurgical support. Military surgeons in the control group were faster. The HMD showed no hard technical errors. Conclusions It is feasible to provide telemedicine neurosurgical support with a HMD during a decompressive craniectomy performed by a non-neurosurgically trained military surgeon. All military surgeons showed competence in performing a decompressive craniectomy after receiving a standardized concise lecture. The use of a HMD clearly demonstrated the potential to improve the quality of these neurosurgical procedures performed by military surgeons. [ABSTRACT FROM AUTHOR]

After providing a detailed overview of nanofabrication techniques for plasmonics, we discuss in detail two different approaches for the fabrication of metallic nanostructures based on e-beam lithography. The first approach relies on a negative e-beam resist, followed by ion beam milling, while the second uses a positive e-beam resist and lift-off. Overall, ion beam etching provides smaller and more regular features including tiny gaps between sub-parts, that can be controlled down to about 10 nm. In the lift-off process, the metal atoms are deposited within the resist mask and can diffuse on the substrate, giving rise to the formation of nanoclusters that render the nanostructure outline slightly fuzzy. Scattering cross sections computed for both approaches highlight some spectral differences, which are especially visible for structures that support complex resonances, such as Fano resonances. Both techniques can produce useful nanostructures and the results reported therein should guide the researcher to choose the best suited approach for a given application, depending on the available technology. [ABSTRACT FROM AUTHOR]

The D- and G-band Raman signals from random arrays of vertically aligned, multi-walled carbon nanotubes are significantly enhanced (up to ∼14×) while the signal from the underlying Si substrate is simultaneously attenuated (up to ∼6×) when the nanotubes are dressed, either capped or coated, with Ag. These Ag-induced counter-changes originate with the difference in geometry of the nanotubes and planar Si substrate and contrast in the Ag depositions on the substrate (essentially thin film) and the nanotube (nano-particulate). The surface integral equation technique is used to perform detailed modelling of the electromagnetic response of the system in a computationally efficient manner. Within the modelling the overall antenna response of the Ag-dressed nanotubes is shown to underpin the main contribution to enhancement of the nanotube Raman signal with hot-spots between the Ag nanoparticles making a subsidiary contribution on account of their relatively weak penetration into the nanotube walls. Although additional hot-spot activity likely accounts for a shortfall in modelling relative to experiment it is nonetheless the case that the significant antenna-driven enhancement stands in marked contrast to the hot-spot dominated enhancement of the Raman spectra from molecules adsorbed on the same Ag-dressed structures. The Ag-dressing procedure for amplifying the nanotube Raman output not only allows for ready characterisation of individual nanotubes, but also evidences a small peak at ∼1150 cm−1 (not visible for the bare, undressed nanotube) which is suggested to be due to the presence of trans-polyacetylene in the structures. [ABSTRACT FROM AUTHOR]

Introduction During tactical combat casualty care, life- and limb-saving procedures might also be performed by combat medics. This study assesses whether it is feasible to use a head-mounted display (HMD) to provide telemedicine (TM) support from a consulted senior surgeon for combat medics when performing a two-incision lower leg fasciotomy. Materials and Methods Nine combat medics were randomized into groups to perform a two-incision lower leg fasciotomy. One group used the Vuzix M400 and the second group used the RealWear HMT-1Z1. A third, control, group received no guidance. In the Vuzix M400 group and RealWear HMT-1Z1 group, a senior surgeon examined the results after the two-incision lower leg fasciotomy was finished to assess the release of compartments, possible collateral damage, and performance of the combat medics. In the control group, these results were examined by a surgical resident with expertise in two-incision lower leg fasciotomies. The resident's operative performance questionnaire was used to score the performance of the combat medics. The telehealth usability questionnaire was used to evaluate the usability of the HMDs as perceived by the combat medics. Results Combat medics using an HMD were considered competent in performing a two-incision lower leg fasciotomy (Vuzix: median 3 [range 0], RealWear: median 3 [range 1]). These combat medics had a significantly better score in their ability to adapt to anatomical variances compared to the control group (Vuzix: median 3 [range 0], RealWear: median 3 [range 0], control: median 1 [range 0]; P  = .018). Combat medics using an HMD were faster than combat medics in the control group (Vuzix: mean 14:14 [SD 3:41], RealWear: mean 15:42 [SD 1:58], control: mean 17:45 [SD 2:02]; P  = .340). The overall satisfaction with both HMDs was 5 out of 7 (Vuzix: median 5 [range 0], RealWear: median 5 [range 1]; P  = .317). Conclusions This study shows that it is feasible to use an HMD to provide TM support performance from a consulted senior surgeon for combat medics when performing a two-incision lower leg fasciotomy. The results of this study suggest that TM support might be useful for combat medics during tactical combat casualty care when performing life- and limb-saving procedures. [ABSTRACT FROM AUTHOR]

In this article, we share our vision for a future nanofactory, where plasmonic trapping is used to control the different manufacturing steps associated with the transformation of initial nanostructures to produce complex compounds. All the different functions existing in a traditional factory can be translated at the nanoscale using the optical forces produced by plasmonic nanostructures. A detailed knowledge of optical forces in plasmonic nanostructures is however essential to design such a nanofactory. To this end, we review the numerical techniques for computing optical forces on nanostructures immersed in a strong optical field and show under which conditions approximate solutions, like the dipole approximation, can be used in a satisfactory manner. Internal optical forces on realistic plasmonic antennas are investigated and the reconfiguration of a Fano-resonant plasmonic system using such internal forces is also studied in detail. [ABSTRACT FROM AUTHOR]

Amplitude and phase measurements of the near-field generated by isolated subwavelength apertures in a gold film are presented. The near-field distribution of such a structure is complex and the measured signal strongly depends on the electric field components effectively detected by the experimental setup. By comparing this signal with 3D vectorial calculations we are able to determine which electric field components are effectively measured. The sensitivity of the phase distribution is key to this measurement. The proposed characterization technique should prove extremely useful to calibrate a Scanning near-field optical microscopy (SNOM) beforehand in order to retrieve quantitative information on the polarization of the field distribution under study. [ABSTRACT FROM AUTHOR]

Patients with RA often fail to comply with their therapy. We investigated the extent of non-compliance with D-penicillamine therapy and also whether patients needed continuous treatment after they had shown a therapeutic response. We developed a simple urinary test, measuring cysteine-penicillamine mixed disulphide by a high performance liquid chromatography technique, as an indicator of compliance. Using this method we evaluated compliance in 59 consecutive RA patients attending rheumatology outpatients for monitoring of D-penicillamine therapy. Evidence of poor compliance was shown in 39%. There was no relationship between poor compliance and disease activity. A possible explanation for this paradox emerged from a therapeutic study of the efficacy of intermittent treatment in patients in partial clinical remission on long-term D-penicillamine. In 14 randomly selected patients the daily dose of D-penicillamine was reduced in frequency over 6 months from 250–750 mg daily to the same dose taken 1 week out of every 4. The patients were compared to matched controls who remained on continuous therapy. After 30 months both the intermittent and continuous therapy groups had similar clinical and laboratory scores for disease activity. Our results suggest that many patients may not comply with their prescribed D-penicillamine regime, but such variation in compliance may not be clinically important since intermittent treatment may sustain response in the longer term. [ABSTRACT FROM PUBLISHER]

We report a high-throughput method for the fabrication of metallic nanogap arrays with high-accuracy over large areas. This method, based on shadow evaporation and interference lithography, achieves sub-10 nm gap sizes with a high accuracy of ±1.5 nm. Controlled fabrication is demonstrated over mm2 areas and for periods of 250 nm. Experiments complemented with numerical simulations indicate that the formation of nanogaps is a robust, self-limiting process that can be applied to wafer-scale substrates. Surface-enhanced Raman scattering (SERS) experiments illustrate the potential for plasmonic sensing with an exceptionally low standard-deviation of the SERS signal below 3% and average enhancement factors exceeding 1 × 106. [ABSTRACT FROM AUTHOR]

In this paper, we present the design, fabrication, and characterization of wire grid polarizers. These polarizers show high extinction ratios and high transmission with structure dimensions that are compatible with current complementary metal-oxide-semiconductor (CMOS) technology. To design these wire grids, we first analyze the transmission properties of single apertures. From the understanding of a single aperture, we apply a modal expansion method to model wire grids. The most promising grids are fabricated on both a glass substrate and CMOS photodiode. An extinction ratio higher than 200 is measured. [ABSTRACT FROM AUTHOR]

This document is a response to a letter to the editor regarding a study on telemedicine-guided lower leg fasciotomy performed by combat medics in austere military environments. The authors address several points raised in the letter, including the testing of Head-Mounted Displays (HMDs) in realistic military environments, connectivity solutions for telemedicine support, and the integration of Artificial Intelligence (AI) in medical care. They express interest in continued collaboration and state that the study was partly funded by the Dutch Ministry of Defense. The authors also provide information on the institutional review board approval and funding sources for the study. [Extracted from the article]

Polarisation charge formed on nanostructure surfaces upon optical excitation provides a useful tool to understand the underlying physics of plasmonic systems. Plasmonic simulations in the frequency domain typically calculate the polarisation charge as a complex quantity. In this paper, we provide a pedagogical treatment of the complex nature of the polarisation charge and its relevance in plasmonics, and discuss how naively extracting the real part of the complex quantities to obtain physical information can lead to pitfalls. We analyse the charge distributions on various plasmonic systems and explain how to understand and visualise them clearly using techniques such as phase-correction and polarisation ellipse representation, to extract the underlying physical information. [ABSTRACT FROM AUTHOR]

The construction, alignment, and performance of a setup for broadband wide-angle dispersion measurements, with emphasis on surface plasmon resonance (SPR) measurements, are presented in comprehensive detail. In contrast with most SPR instruments working with a monochromatic source, this setup takes advantage of a broadband/white light source and has full capability for automated angle vs. wavelength dispersion measurements for any arbitrary nanostructure array. A cylindrical prism is used rather than a triangular one in order to mitigate refraction induced effects and allow for such measurements. Although seemingly simple, this instrument requires use of many non-trivial methods in order to achieve proper alignment over all angles of incidence. Here we describe the alignment procedure for such a setup, the pitfalls introduced from the finite beam width incident onto the cylindrical prism, and deviations in the reflected/transmitted beam resulting from the finite thickness of the sample substrate. We address every one of these issues and provide experimental evidences on the success of this instrument and the alignment procedure used. [ABSTRACT FROM AUTHOR]

Introduction: Advanced bleeding control options for truncal and junctional haemorrhage including resuscitative endovascular balloon occlusion of the aorta (REBOA) have been used in managing catastrophic bleeding. The primary aim is to report on potential indications for advanced bleeding control in combat casualties during the Dutch deployment in Uruzgan, Afghanistan, between August 2006 and August 2010. The secondary aim is to report on training methods for advanced bleeding control in (para)medical personnel., Methods: The trauma registry from the Dutch role 2 enhanced medical treatment facility at Tarin Kowt, Uruzgan, Afghanistan, was used to analyse patients who sustained a battle injury with major haemorrhage. Furthermore, a comprehensive search was performed on training (para)medical personnel in advanced bleeding control., Results: There were 212 possible indications for advanced bleeding control with mortality of 28.8% (61/212). These possible indications consisted of 1.9% (4/212) junctional lower extremity injuries with a 75% (3/4) mortality rate, 59% (125/212) visceral vascular injuries with a mortality rate of 12.5% (26/125). The junctional and visceral injuries (n=129) were all potential indications for advanced bleeding control options, such as REBOA. Further 39.2% (83/212) casualties with central thoracic or neck injuries had a mortality rate of 38.6% (32/83). Based on an Abbreviated Injury Scale chest or abdomen score ≥461 indications for advanced bleeding control were identified. A 24-hour average of 8.8 packets of red blood cells, 4.2 packets of plasma and 1.9 packets of platelets was used to prevent exsanguination. The total out-of-hospital survival rate was 64% (39/61)., Conclusion: Retrospective analysis revealed 212 potential indications for advanced bleeding control with a mortality of 28.8% (61/212). Advanced bleeding control, such as REBOA, might have improved survival in approximately 61 of 212 casualties. Advanced bleeding control could be used as an adjunct to improve outcomes in major truncal or junctional haemorrhage in prehospital, remote settings and implementation should be considered. Vascular access training and REBOA placement for (para)medical military personnel should be explored in future research., Competing Interests: Competing interests: None declared., (© Author(s) (or their employer(s)) 2020. No commercial re-use. See rights and permissions. Published by BMJ.)

Background: The primary aim was to assess survival of opening wedge high tibial osteotomy (HTO) for medial compartment osteoarthritis. The secondary aim was to identify independent predictors of early conversion to total knee arthroplasty (TKA)., Methods: During the 18-year period (1994-2011) 111 opening wedge HTO were performed at the study centre. Mean age was 45 years (range 18-68) and the majority male (84%). Mean follow-up was 12 (range six to 21) years. Failure was defined as conversion to TKA. Kaplan-Meier, Cox regression and receiver operating curve (ROC) analyses were performed., Results: Forty (36.0%) HTO failed at a mean of 6.3 years (range one to 15). By Kaplan-Meier analysis, the five-year survival rate was 84% (95% confidence interval (CI) 82.6-85.4), 10-year rate 65% (95% CI 63.5-66.5) and 15-year rate 55% (95% CI 53.3-56.7). Cox regression analysis identified older age (hazard ratio (HR) 1.07 for each additional year, 95% CI 1.03-1.11, p b 0.001) and female gender (HR 2.37, 95% CI 1.06-5.33, p = 0.04) as independent predictors of failure. ROC analysis identified a threshold age of 47 years above which the risk of failure increased significantly (area under curve 0.72, 95% CI 0.62-0.81, p b 0.001). Cox regression analysis, adjusting for covariates, identified a significantly greater (HR 2.49, 95% CI 1.26-4.91, p = 0.01) risk of failure in patients aged 47 years old or more., Conclusion: The risk of early conversion to TKA is significantly increased in females and those older than 47. These risk factors should be considered pre-operatively when planning intervention for isolated medial compartment osteoarthritis., (Copyright © 2018 Elsevier B.V. All rights reserved.)

C-reactive protein (CRP) is one of the most expressed proteins in blood during acute phase inflammation, and its minute level increase has also been recognized for the clinical diagnosis of cardio vascular diseases. Unfortunately, the available commercial immunoassays are labour intensive, require large sample volumes, and have practical limitations, such as low stability and high production costs. Hence, we have developed a simple, cost effective, and label-free electrochemical immunoassay for the measurement of CRP in a drop of serum sample using an immunosensor strip made up of a screen printed carbon electrode (SPE) modified with anti-CRP functionalized gold nanoparticles (AuNPs). The measurement relies on the decrease of the oxidation current of the redox indicator Fe 3+ /Fe 2+ , resulting from the immunoreaction between CRP and anti-CRP. Under optimal conditions, the present immunoassay measures CRP in a linear range from 0.4-200 nM (0.047-23.6 µg mL -1 ), with a detection limit of 0.15 nM (17 ng mL -1 , S/N = 3) and sensitivity of 90.7 nA nM -1 , in addition to a good reproducibility and storage stability. The analytical applicability of the presented immunoassay is verified by CRP measurements in human blood serum samples. This work provides the basis for a low-priced, safe, and easy-to-use point-of-care immunosensor assay to measure CRP at clinically relevant concentrations., Competing Interests: The authors declare no conflict of interest.

Large tibial defects present a challenging scenario for the orthopaedic surgeon, particularly in the paediatric patient. Most management options, such as the vascularised fibular graft or Ilizarov technique, require microsurgical techniques or specialist equipment. In an austere environment, acute shortening or limb amputation may be most appropriate. However, limb salvage may be achieved by ipsilateral fibular transfer. In a one-stage operation, the fibular graft is harvested and either placed in the tibial defect in an intramedullary position or secured to the tibia with screws. We present two paediatric cases where this approach was used to preserve the lower limb despite extensive explosive trauma. In the first case, an 11 cm tibial defect was managed with an ipsilateral fibular graft. The graft was placed in an intercalary position proximally, with medial displacement of the ankle and fixation of the fibula as a strut graft. In the second case, a 10 cm tibial defect was managed with an ipsilateral fibular graft, using intercalary placement proximally and distally. Both children returned to weight bearing with crutches within several months of surgery. For large tibial defects, ipsilateral fibular transfer is an effective one-stage operation that represents a viable alternative to amputation in austere environments., (Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.)

We exploit the versatility provided by metal-dielectric composites to demonstrate controllable coherent perfect absorption (CPA) or anti-lasing in a slab of heterogeneous medium. The slab is illuminated by coherent light from both sides, at the same angle of incidence and the conditions required for CPA are investigated as a function of the different system parameters. Our calculations clearly elucidate the role of absorption as a necessary prerequisite for CPA. We further demonstrate the controllability of the CPA frequency to the extent of having the same at two distinct frequencies even in presence of dispersion, rendering the realization of anti-lasers more flexible.

The electric field enhancement associated with detailed structure within novel optical antenna nanostructures is modeled using the surface integral equation technique in the context of surface-enhanced Raman scattering (SERS). The antennae comprise random arrays of vertically aligned, multiwalled carbon nanotubes dressed with highly granular Ag. Different types of "hot-spot" underpinning the SERS are identified, but contrasting characteristics are revealed. Those at the outer edges of the Ag grains are antenna driven with field enhancement amplified in antenna antinodes while intergrain hotspots are largely independent of antenna activity. Hot-spots between the tops of antennae leaning towards each other also appear to benefit from antenna amplification.