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Reconfigurable optical systems are the object of continuing, intensive research activities, as they hold great promise for realizing a new generation of compact, miniaturized, and flexible optical devices. However, current reconfigurable systems often tune only a single state variable triggered by an external stimulus, thus, leaving out many potential applications. Here we demonstrate a reconfigurable multistate optical system enabled by phase transitions in vanadium dioxide (VO 2 ). By controlling the phase-transition characteristics of VO 2 with simultaneous stimuli, the responses of the optical system can be reconfigured among multiple states. In particular, we show a quadruple-state dynamic plasmonic display that responds to both temperature tuning and hydrogen-doping. Furthermore, we introduce an electron-doping scheme to locally control the phase-transition behavior of VO 2 , enabling an optical encryption device encoded by multiple keys. Our work points the way toward advanced multistate reconfigurable optical systems, which substantially outperform current optical devices in both breadth of capabilities and functionalities., Competing Interests: The authors declare no competing financial interest., (© 2020 American Chemical Society.)

Molecular chirality is a geometric property that is of great importance in chemistry, biology, and medicine. Recently, plasmonic nanostructures that exhibit distinct chiroptical responses have attracted tremendous interest, given their ability to emulate the properties of chiral molecules with tailored and pronounced optical characteristics. However, the optical chirality of such human-made structures is in general static and cannot be manipulated postfabrication. Herein, different concepts to reconfigure the chiroptical responses of plasmonic nano- and micro-objects are outlined. Depending on the utilized strategies and stimuli, the chiroptical signature, the 3D structural conformation, or both can be reconfigured. Optical devices based on plasmonic nanostructures with reconfigurable chirality possess great potential in practical applications, ranging from polarization conversion elements to enantioselective analysis, chiral sensing, and catalysis., (© 2020 The Authors. Published by WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Displays are an indispensable medium to visually convey information in our daily life. Although conventional dye-based color displays have been rigorously advanced by world leading companies, critical issues still remain. For instance, color fading and wavelength-limited resolution restrict further developments. Plasmonic colors emerging from resonant interactions between light and metallic nanostructures can overcome these restrictions. With dynamic characteristics enabled by functional materials, dynamic plasmonic coloration may find a variety of applications in display technologies. In this review, we elucidate basic concepts for dynamic plasmonic color generation and highlight recent advances. In particular, we devote our review to a selection of dynamic controls endowed by functional materials, including magnesium, liquid crystals, electrochromic polymers, and phase change materials. We also discuss their performance in view of potential applications in current display technologies., (Copyright © 2020 The Authors, some rights reserved; exclusive licensee American Association for the Advancement of Science. No claim to original U.S. Government Works. Distributed under a Creative Commons Attribution NonCommercial License 4.0 (CC BY-NC).)

Background: Traumatic peripheral nerve injuries can result in significant functional impairments and long-term sequelae. This study evaluated the long-term outcomes of a chitosan tube implant to protect epineural coaptation after peripheral nerve injuries using 2 different tube versions (different wall thicknesses and resorption characteristics), compared with a control group. The study focused on pain levels, sensory function, and overall functional outcomes., Methods: Patients who received a tube implant around direct coaptation sites of digital nerves were randomized and compared with control patients with no additional tube protection. Pain levels, sensory function, grip force, and functional scores were assessed at time points ranging from 3 months to 5 years postoperatively. Tube biodegradation was measured using high-resolution magnetic resonance neurography and categorized., Results: Patients with the first tube version had higher pain levels compared with the control group after 5 years, and reported more symptoms of numbness and hypersensitivity. Patients with the second version exhibited higher pain levels at 3 months that did not persist at 6 months, but they showed compromised sensory function, with higher 2-point discrimination values compared with the first and control groups. No differences were found in grip force or functional scores between the groups. Magnetic resonance imaging displayed remnants of implants even at long-term follow-up., Conclusions: The findings suggest potential limitations attributable to increased pain and impaired sensory function associated with tube implantation in the long term. In the short term, however, the material seemed to have a protective effect (as published previously). The resorption process was not complete at the end of the 5-year observation period. This might explain the prolonged scarring and inferior long-term results. Future research should focus on improving tube materials and design to minimize adverse effects and enhance functional outcomes., (Copyright © 2024 by the American Society of Plastic Surgeons.)

Metacarpal and phalangeal fractures are the second most frequent fractures of the upper extremity. Treatment goal is to restore the function of the injured hand. Due to better understanding of anatomy and biomechanics as well as the development of locking and low-profile implants for osteosynthesis of such fractures, there is a growing safety when choosing the operative treatment for the correct indication. Nevertheless, conservative treatment of these injuries still plays an important role., Competing Interests: Die Autoren geben an, dass kein Interessenkonflikt besteht., (Georg Thieme Verlag KG Stuttgart · New York.)

Selective transport and concentration of molecules to specified regions on a substrate both enhances the potential to detect such molecules and provides a path to spatially localize such molecules prior to initiation of subsequent chemical reactions. Here, we first embed radially symmetric α-, β-, and γ-cyclodextrin gradients in a hydrogel matrix. Driven by host-guest interactions between the cyclodextrins and the target molecule, we observe these gradients can serve to direct 2D molecular transport. Using xanthene dyes and organophosphates as target molecules, we found the transport metrics, e.g., selectivity, rate, and concentration limits, are strongly dependent on the specific cyclodextrin forming the gradient. In all cases, as the concentrating power of the gradient increased, the rate of target concentration slowed, which we hypothesize is because stronger interactions between the target and the cyclodextrin decrease the rate of target diffusion. The concentration enhancement for the nerve agent simulant 4-methylumbelliferyl phosphate (15.8) is the greatest when the gradient is formed using β-cyclodextrin while directed concentration of cyanomethyl phosphonate, a smaller non-aromatic organophosphate, is observed only for the smaller α-CD. To provide a near real-time read-out of the concentration of the analyte, we used an array of IR resonant metallic nanoantennas tuned to a specific IR absorption band of the analyte to enhance the IR signal generated by the analyte., (© 2019 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Proteins perform a variety of essential functions in living cells and thus are of critical interest for drug delivery as well as disease biomarkers. The different functions are derived from a hugely diverse set of structures, fueling interest in their conformational states. Surface-enhanced infrared absorption spectroscopy has been utilized to detect and discriminate protein monomers. As an important step forward, we are investigating collagen peptides consisting of  a  triple helix. While they constitute the main structural building blocks in many complex proteins, they are also a perfect model system for the complex proteins relevant in biological systems. Their complex spectroscopic information as well as the overall small size present a significant challenge for their detection and discrimination. Using resonant plasmonic nanoslits, which are known to show larger specificity compared to nanoantennas, we overcome this challenge. We perform in vitro surface-enhanced absorption spectroscopy studies and track the conformational changes of these collagen peptides under two different external stimuli, which are temperature and chemical surroundings. Modeling the coupling between the amide I vibrational modes and the plasmonic resonance, we can extract the conformational state of the collages and thus monitor the folding and unfolding dynamics of even a single monolayer. This leads to new prospects in studies of single layers of proteins and their folding behavior in minute amounts in a living environment.

Monosaccharides, which include the simple sugars such as glucose and fructose, are among the most important carbohydrates in the human diet. Certain chronic diseases, e.g., diabetes mellitus, are associated with anomalous glucose blood levels. Detecting and measuring the levels of monosaccharides in vivo or in aqueous solutions is thus of the utmost importance in life science, health, and point-of-care applications. Noninvasive sensing would avoid problems such as pain and potential infection hazards. Here, with the help of surface enhanced infrared absorption (SEIRA) spectroscopy, we demonstrate the reliable optical detection in the mid-infrared spectral range of pure glucose and fructose solutions as well as mixtures of both in aqueous solution. We utilize a reflection flow cell geometry with physiologically relevant concentrations as small as 10 g/L. As significant improvement over the standard baseline correction employed in SEIRA applications, we utilize principal component analysis (PCA) as machine learning algorithm, which is ideally suited for the extraction of vibrational data. We anticipate our results as important step in biosensing applications that will stimulate efforts to further improve the employed SEIRA substrates, the noise level of the spectroscopic light source, as well as the flow cell environment en route to significantly higher sensitivities and quantitative analysis, even in tear drops.

Proteins and peptides play a predominant role in biochemical reactions of living cells. In these complex environments, not only the constitution of the molecules but also their three-dimensional configuration defines their functionality. This so-called secondary structure of proteins is crucial for understanding their function in living matter. Misfolding, for example, is suspected as the cause of neurodegenerative diseases such as Alzheimer's and Parkinson's disease. Ultimately, it is necessary to study a single protein and its folding dynamics. Here, we report a first step in this direction, namely ultrasensitive detection and discrimination of in vitro polypeptide folding and unfolding processes using resonant plasmonic nanoantennas for surface-enhanced vibrational spectroscopy. We utilize poly-l-lysine as a model system which has been functionalized on the gold surface. By in vitro infrared spectroscopy of a single molecular monolayer at the amide I vibrations we directly monitor the reversible conformational changes between α-helix and β-sheet states induced by controlled external chemical stimuli. Our scheme in combination with advanced positioning of the peptides and proteins and more brilliant light sources is highly promising for ultrasensitive in vitro studies down to the single protein level.

Metasurfaces enable manipulation of light propagation at an unprecedented level, benefitting from a number of merits unavailable to conventional optical elements, such as ultracompactness, precise phase and polarization control at deep subwavelength scale, and multifunctionalities. Recent progress in this field has witnessed a plethora of functional metasurfaces, ranging from lenses and vortex beam generation to holography. However, research endeavors have been mainly devoted to static devices, exploiting only a glimpse of opportunities that metasurfaces can offer. We demonstrate a dynamic metasurface platform, which allows independent manipulation of addressable subwavelength pixels at visible frequencies through controlled chemical reactions. In particular, we create dynamic metasurface holograms for advanced optical information processing and encryption. Plasmonic nanorods tailored to exhibit hierarchical reaction kinetics upon hydrogenation/dehydrogenation constitute addressable pixels in multiplexed metasurfaces. The helicity of light, hydrogen, oxygen, and reaction duration serve as multiple keys to encrypt the metasurfaces. One single metasurface can be deciphered into manifold messages with customized keys, featuring a compact data storage scheme as well as a high level of information security. Our work suggests a novel route to protect and transmit classified data, where highly restricted access of information is imposed.

Background: Vascularized composite allotransplantation (VCA) is a rapidly expanding field of transplantation and provides a potential treatment for complex tissue defects. Peripheral blood mononuclear cells (PBMCs) shortly incubated with the antibiotic and chemotherapeutic agent mitomycin C (MMC) can suppress allogeneic T cell response and control allograft rejection in various organ transplantation models. MMC-incubated PBMCs (MICs) are currently being tested in a phase I clinical trial in kidney transplant patients. Previous studies with MICs in a complex VCA model showed the immunomodulatory potential of these cells. The aim of this study is to optimize and evaluate the use of MICs in combination with a standard immunosuppressive drug in VCA., Methods: Fully mismatched rats were used as hind limb donors [Lewis (RT1 1 )] and recipients [Brown-Norway (RT1 n )]. Sixty allogeneic hind limb transplantations were performed in six groups. Group A received donor-derived MICs combined with a temporary ciclosporin A (CsA) treatment. Group B received MICs in combination with a temporarily administered reduced dose of CsA. Group C served as a control and received a standard CsA dose temporarily without an additional administration of MICs, whereas Group D was solely medicated with a reduced CsA dose. Group E received no immunosuppressive therapy, neither CsA nor MICs. Group F was given a continuous standard immunosuppressive regimen consisting of CsA and prednisolone. The endpoint of the study was the onset of allograft rejection which was assessed clinically and histologically., Results: In group A and B, the rejection-free interval of the allograft was significantly prolonged to an average of 23.1 ± 1.7 and 24.7 ± 1.8 days compared to the corresponding control groups (p < 0.01). Rejection in groups C, D, and E was noted after 14.3 ± 1.1, 7.8 ± 0.7, and 6.9 ± 0.6 days. No rejection occurred in control group F during the follow-up period of 100 days. No adverse events have been noted., Conclusion: The findings of this study show that the combination of MICs with a temporary CsA treatment significantly prolongs the rejection-free interval in a complex VCA model. The combination of MICs with CsA showed no adverse events such as graft-versus-host disease. MICs, which are generated by a simple and reliable in vitro technique, represent a potential therapeutic tool for prolonging allograft survival through immunomodulation.

In this article, a chiral plasmonic hydrogen-sensing platform using palladium-based nanohelices is demonstrated. Such 3D chiral nanostructures fabricated by nanoglancing angle deposition exhibit strong circular dichroism both experimentally and theoretically. The chiroptical properties of the palladium nanohelices are altered upon hydrogen uptake and sensitively depend on the hydrogen concentration. Such properties are well suited for remote and spark-free hydrogen sensing in the flammable range. Hysteresis is reduced, when an increasing amount of gold is utilized in the palladium-gold hybrid helices. As a result, the linearity of the circular dichroism in response to hydrogen is significantly improved. The chiral plasmonic sensor scheme is of potential interest for hydrogen-sensing applications, where good linearity and high sensitivity are required., (© 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

We demonstrate surface enhanced infrared absorption spectroscopy using 1-dimensional highly doped semiconductors based on Si-doped InAsSb plasmonic nano-antennas. Engineering the plasmonic array to support the localized surface plasmon resonance aligned with the molecular vibrational absorption mode of interest involves finely setting the doping level and nano-antenna width. Heavily doped nano-antennas require a wider size compared to lightly doped resonators. Increasing the doping level, and consequently the width of the nano-antenna, enhances the vibrational absorption of a ~15 nm thick organic layer up to 2 orders of magnitude compared to the unstructured sample and therefore improves sensing. These results pave the way towards molecule fingerprint sensor manufacturing by tailoring the plasmonic resonators to get a maximum surface enhanced infrared absorption at the target vibrational mode.

High-resolution multicolor printing based on pixelated optical nanostructures is of great importance for promoting advances in color display science. So far, most of the work in this field has been focused on achieving static colors, limiting many potential applications. This inevitably calls for the development of dynamic color displays with advanced and innovative functionalities. In this Letter, we demonstrate a novel dynamic color printing scheme using magnesium-based pixelated Fabry-Pérot cavities by gray scale nanolithography. With controlled hydrogenation and dehydrogenation, magnesium undergoes unique metal and dielectric transitions, enabling distinct blank and color states from the pixelated Fabry-Pérot resonators. Following such a scheme, we first demonstrate dynamic Ishihara plates, in which the encrypted images can only be read out using hydrogen as information decoding key. We also demonstrate a new type of dynamic color generation, which enables fascinating transformations between black/white printing and color printing with fine tonal tuning. Our work will find wide-ranging applications in full-color printing and displays, colorimetric sensing, information encryption and anticounterfeiting.

Background  This paper investigates and discusses the effect of perioperative plexus catheter treatment in former CRPS patients. Patients and Methods A retrospective matched-pair analysis was conducted on 10 CRPS patients with comparable injuries, who underwent surgery in the disease-free interval. In 10 cases, the procedure was performed with perioperative plexus catheter treatment (intervention group), whereas 10 patients did not receive perioperative plexus catheter treatment (control group). Results  In the intervention group, after a follow-up time of 105 (20-184) days after the last surgical procedure, pain intensity on the visual analogue scale (VAS; 0 to 10) was 6.4 (4-8), fingertip-to-palm distance averaged 3.2 (0-7.6) cm, active range of wrist motion was 47.5 (0-95), and grip strength was 9.2 (2.1-16.6) kg. In the control group, after a follow-up time of 129 (19-410) days since the last surgical procedure, pain intensity on the visual analogue scale was 6 (3-10), fingertip-to-palm distance averaged 2.7 (0-4.5) cm, active range of wrist-motion was 64 (0-125), and grip strength was 12.4 (0.8-23.8) kg. There was no significant difference between the groups. There was no recurrence of CRPS disease in either group after surgery. Conclusion  There is no evidence so far for perioperative plexus catheter treatment to prevent recurrence in former CRPS patients., Competing Interests: Interessenkonflikte: Die Autoren geben an, dass kein Interessenkonflikt besteht., (Georg Thieme Verlag KG Stuttgart · New York.)

Background  High-pressure injection injuries are devastating injuries that often lead to an amputation of the primarily affected finger. The available literature mainly focuses on amputation rates, while there is a lack of knowledge regarding functional results. Patients and Methods  Between 1998 and 2016, 47 cases of high-pressure injection injuries of the hand were registered in our department. Out of these, data of 26 patients, all men with an average age of 42 (18-62) years, were included in a retrospective follow-up examination after 4 (1-12) years. We recorded DASH scores, pain intensity on visual analogue scales (VAS, 1-10), fingertip-to-palm distance, active range of wrist motion, grip strength, and two-point-discrimination ability (2PD). The statistical analysis was descriptive and was performed by analysis of correlation. Results  The average DASH score of these 26 patients was 45 (30-93), pain intensity was 2.5 (0-9) on the VAS, fingertip-to-palm distance was 1 (0-4) cm. Active range of wrist motion was 99 (77-122) % of the contralateral side. Average grip strength was reduced to 67 (0-164) % of the contralateral side. Average 2PD was 9 (2-25) mm. Nineteen out of 26 patients returned to work. An amputation was necessary in 7 out of 26 cases. These patients had more pain and less grip strength. High latency from injury to operative treatment impaired functional outcome, which was statistically significant for DASH (p < 0.05). A trend to poorer outcomes was noted in cases of a more distal lesion and injection of toxic substances, whereas high injection pressure had no negative influence. Conclusion  High-pressure injection injuries have serious consequences regarding hand function and frequently cause chronic pain. This affects patients with finger preservation as well as patients requiring an amputation. A further evaluation of prognostic factors requires a metaanalysis of functional parameters. The DASH score seems to be an expedient assessment tool., Competing Interests: Interessenkonflikt: Die Autoren geben an, dass kein Interessenkonflikt besteht., (Georg Thieme Verlag KG Stuttgart · New York.)

Spectroscopic infrared chemical imaging is ideally suited for label-free and spatially resolved characterization of molecular species, but often suffers from low infrared absorption cross sections. Here, we overcome this limitation by utilizing confined electromagnetic near-fields of resonantly excited plasmonic nanoantennas, which enhance the molecular absorption by orders of magnitude. In the experiments, we evaporate microstructured chemical patterns of C 60 and pentacene with nanometer thickness on top of homogeneous arrays of tailored nanoantennas. Broadband mid-infrared spectra containing plasmonic and vibrational information were acquired with diffraction-limited resolution using a two-dimensional focal plane array detector. Evaluating the enhanced infrared absorption at the respective frequencies, spatially resolved chemical images were obtained. In these chemical images, the microstructured chemical patterns are only visible if nanoantennas are used. This confirms the superior performance of our approach over conventional spectroscopic infrared imaging. In addition to the improved sensitivity, our technique provides chemical selectivity, which would not be available with plasmonic imaging that is based on refractive index sensing. To extend the accessible spectral bandwidth of nanoantenna-enhanced spectroscopic imaging, we employed nanostructures with dual-band resonances, providing broadband plasmonic enhancement and sensitivity. Our results demonstrate the potential of nanoantenna-enhanced spectroscopic infrared chemical imaging for spatially resolved characterization of organic layers with thicknesses of several nanometers. This is of potential interest for medical applications which are currently hampered by state-of-art infrared techniques, e.g., for distinguishing cancerous from healthy tissues.

Infrared spectroscopy is a powerful tool widely used in research and industry for a label-free and unambiguous identification of molecular species. Inconveniently, its application to spectroscopic analysis of minute amounts of materials, for example, in sensing applications, is hampered by the low infrared absorption cross-sections. Surface-enhanced infrared spectroscopy using resonant metal nanoantennas, or short "resonant SEIRA", overcomes this limitation. Resonantly excited, such metal nanostructures feature collective oscillations of electrons (plasmons), providing huge electromagnetic fields on the nanometer scale. Infrared vibrations of molecules located in these fields are enhanced by orders of magnitude enabling a spectroscopic characterization with unprecedented sensitivity. In this Review, we introduce the concept of resonant SEIRA and discuss the underlying physics, particularly, the resonant coupling between molecular and antenna excitations as well as the spatial extent of the enhancement and its scaling with frequency. On the basis of these fundamentals, different routes to maximize the SEIRA enhancement are reviewed including the choice of nanostructures geometries, arrangements, and materials. Furthermore, first applications such as the detection of proteins, the monitoring of dynamic processes, and hyperspectral infrared chemical imaging are discussed, demonstrating the sensitivity and broad applicability of resonant SEIRA.

Finger replantations demand technical excellence in microsurgery and hand trauma care. The objective of this study was to determine whether finger replantations constitute an appropriate and safe procedure for residency training. Additionally, the prognostic risk factors for the need to take a replanted finger back to the operation room and replant failure were analyzed.All patients who underwent finger replantation after complete amputation between 2007 and 2015 were included in a retrospective comparative study. These patients were either treated by an attending plastic surgeon (cohort 1) or by a postgraduate year 5 or 6 resident under supervision (cohort 2). Logistic regression analysis was used to identify the prognostic risk factors for emergent take backs and replant failures.A total of 109 completely amputated fingers were replanted in 89 patients. Fifty-seven digits were replanted in cohort 1, and 52 digits were replanted in cohort 2. Patient demographic data revealed an equal distribution between the two cohorts with an overall finger-replantation success rate of 67.0%. The prognostic risk factors related to increased take back and replant failure rates were fewer than two venous anastomoses (take back odds ratio [AOR], 0.27; confidence interval (CI), 0.12-0.63; and replant failure AOR, 0.21; 95% CI, 0.08-0.55) and intraoperative noticeable problems regarding the vascular anastomoses (take back AOR, 2.26; 95% CI, 0.96-5.33 and replant failure AOR, 2.45; 95% CI, 1.00-6.00). The type of surgeon did not exhibit an influence on the risk of take back (OR, 1.14; 95% CI, 0.53-2.41) or replant failure (OR, 1.03; 95% CI, 0.46-2.30). Similarly, after adjusting for all risk factors, the risks for take backs (AOR, 1.04; 95% CI, 0.46-2.36) and replant failures (AOR, 0.91; 95% CI, 0.38-2.19) did not differ between the 2 cohorts.Finger replantations can be applied as a safe procedure in residency training under standardized conditions and do not negatively affect quality of care. Technical proficiency in microsurgery and elective and trauma hand care as well as supervision by an experienced plastic or hand surgeon are mandatory. Regardless of the surgeons' experience, fewer than 2 venous anastomoses and the presence of intraoperative vascular anomalies represent significant prognostic risk factors for postoperative complications.

Purpose: The clinical course after major burns is characterized by microcirculatory changes and consecutive capillary leakage. However, current clinical monitoring does not properly assess microcirculation, whereas macrohemodynamic changes are continuously evaluated. Here, we assess if macrohemodynamic and microhemodynamic parameters after burn trauma are correlated in a rat model., Methods: Burn plasma harvested from donor rats 4 hours after thermal injury (30% total body surface area, 100 °C water, 12 seconds) was administered intravenously to healthy animals during 2 hours of intravital microscopy (burn group [BG]). Shamburn plasma (same procedure but water at 37°C) was transferred for negative controls (shamburn group [SBG]). Intravital microscopy was performed at 0, 60, and 120 minutes to assess capillary leakage measuring fluorescein isothiocyanate-albumin extravasation. Macrocirculation was assessed using mean arterial pressure and heart rate, whereas microcirculation was evaluated using red blood cell velocity, venular diameter, venular wall shear rate and plasma extravasation at 0, 60, and 120 minutes in postcapillary venules., Results: Thirty mesenteric venules (16 animals) in SBG and 31 mesenteric venules (15 animals) in BG were observed during intravital microscopy. Mean arterial pressure and heart rate remained within acceptable margins and showed no significant differences, neither within nor between groups. Significant correlations between macrohemodynamic and microhemodynamic conditions were neither observed for BG nor SBG, except from a significant correlation of MAP and plasma extravasation at T60. However, at T120 mesenteric venules in the BG clearly showed microvascular burn edema, whereas venules in SBG did not., Conclusions: Stabilization of macrohemodynamic conditions may not necessarily have positive effects on microcirculatory derangements-a fact that has not been shown for burns yet, that is-however, well described for sepsis. Further studies are required to show whether distinct monitoring of microcirculation may offer new approaches for burn trauma treatment.

We perform far-field spectroscopy of infrared metal antennas on silicon oxide layers of different thickness, where we find a splitting of the plasmonic resonance. This splitting can result in a transparency window, corresponding to suppression of antenna scattering, respectively "cloaking" of the antenna. Backed up by theory, we show that this effect is caused by strong coupling between the metal antenna plasmons and the surface phonon polaritons in the oxide layer. The effect is a kind of induced transparency in which the strength of the phonon-polariton field plays the crucial role. It represents a further tuning possibility for the optical performance of infrared devices.

Background: In the current literature, there are reports of associations between complex regional pain syndromes (CRPS) and carpal tunnel syndromes (CTS). The aim of this study was to determine the prevalence of both disease patterns in hand rehabilitation patients and to investigate whether there is a correlation between CTS and CRPS. Furthermore, differences in the healing process of patients with and without additional CTS, and the effectiveness of the rehabilitative therapy for both diseases, were investigated., Patients and Methods: The computerised medical records of 791 patients in the years 2009-2015 who had been in hand rehabilitation were retrospectively analysed. At the beginning and end of rehabilitation, measurements were made of pain by visual analogue scales (VAS, 0-10), grip strength and finger mobility (mean distance from finger pulp to palmar D2-D5). The clinical course was statistically analysed. CRPS diagnosis was confirmed clinically by a pain therapist, CTS diagnosis was confirmed by neurological and neurophysiological examination. Surgical therapy was performed despite CRPS diagnosis., Results: The prevalence of CRPS was 161/1000 and of CTS 62/1000; the co-prevalence of the 2 diagnoses was 24/1000 (p<0.0001). In the CRPS group, after a mean of 8 (1-21) weeks of rehabilitative therapy, mean pain was reduced from 5 (1-10) to 3 (0-9), grip strength improved from 10 (0-39)kg to 18.5 (2.5-45.5)kg and finger mobility increased from 2.9 (0-7.6)cm to 1.8 (0-7.8)cm. In the CRPS+CTS group, after a mean of 6.8 (3-23) weeks of rehabilitative therapy, mean pain was reduced from 5 (0-8) to 2.6 (0-5), grip strength improved from 9.7 (2.4-25.5)kg to 17.4 (0.9-47.4)kg and finger mobility increased from 2.7 (0-5.3)cm to 1.7 (0-5.3)cm. Improvement over the period of rehabilitation was significant in both groups, though the period of therapy was significantly shorter in the CRPS+CTS group., Conclusion: CRPS and CTS are often associated. Rehabilitative therapy was effective for CRPS- and CRPS+CTS patients., (© Georg Thieme Verlag KG Stuttgart · New York.)

Background: Nerve tubes are used for bridging of short nerve gaps and for coating of primary end-to-end nerve sutures. This article provides an overview of available implants and their application. Also it presents a retrospective planning study aiming to determine the static 2-point discrimination after primary peripheral nerve repair with and without the use of a nerve tube. The results have been used to determine the sample size of a prospective randomised trial., Patients and Methods: 54 peripheral nerve injuries of 41 patients were treated by primary end-to-end nerve sutures with or without the additional use of a nerve tube (n=28 and n=26, respectively). 38 digital nerves and 16 median and ulnar nerves were affected. Nerve tubes were used for the repair of 15 digital nerves and 13 median and ulnar nerves. Clinical follow-up was performed 46 months after surgery (patients without nerve tubes) and 18 months after surgery (patients with nerve tubes), respectively. Static 2-point discrimination (2PD) was measured by double-tip compasses (weight: 18 g) and patients were examined for clinical signs of neuroma. Further examinations included grip strength as a percentage value compared with the uninjured hand and, in case of finger injuries, the range of motion in the proximal and distal interphalangeal joints, Strickland score, DASH score and implant-associated complications., Results: In patients with primary end-to-end sutures for finger injuries, there were no statistically significant differences between treatment with and without nerve tubes regarding 2PD, grip strength, DASH- or Strickland score. However, 2PD values of patients with nerve tubes had an increased spread. Average 2PD in digital nerves was 4.5 mm (3-15; SD: 3.9) without nerve tubes and 5.5 mm (3-15; SD: 5) with nerve tubes. Average 2PD after lesions of the median and ulnar nerves was 10 mm (3-15; SD: 5.9 and 5.4, respectively) in both groups., Conclusion: The additional use of a nerve tube showed no superiority in this planning study. The expected average 2PD is 5 mm after digital nerve injuries and 10 mm after lesions of the median or ulnar nerves., (© Georg Thieme Verlag KG Stuttgart · New York.)

The sensitivity in surface enhanced infrared spectroscopy (SEIRS) strongly depends on where the resonant excitation is spectrally located compared to the molecular vibration that is to be enhanced. In this contribution, we study the effect of coupling in the electromagnetic properties of 2D gold nanorod arrays in the IR. We also study the SEIRS activity of higher order resonant excitations in long nanoantennas to identify polaritonic signals of a supporting SiO2 layer with nanometer thickness (3 nm) on a silicon substrate. [ABSTRACT FROM AUTHOR]

Background: Bioethanol-fueled fireplaces are popular interior home decoration accessories. Although their safety is promoted frequently, actual presentations of severe burn injuries in our burn intensive care unit (ICU) have focused the authors on safety problems with these devices. In this article we want to explore the mechanisms for these accidents and state our experiences with this increasingly relevant risk for severe burn injuries., Materials and Methods: The computerized medical records of all burn intensive care patients in our burn unit between 2000 and 2014 were studied. Since 2010, 12 patients with bioethanol associated burn injuries were identified. Their data was compared to the values of all patients, except the ones injured by bioethanol fireplaces that presented themselves to our burn ICU between the years 2010 and 2014., Results: At time of admission the bioethanol patients had a mean ABSI-score of 4.8 (+/- 2.2 standard deviation (SD)). A mean of 17 percent (+/- 9.1 SD) body surface area was burned. Involvement of face and hands was very common. An operative treatment was needed in 8 cases. A median of 20 days of hospitalization (range 3-121) and a median of 4.5 days on the ICU (range 1-64) were necessary. No patient died. In most cases the injuries happened while refilling or while starting the fire, even though safety instructions were followed. In the control group, consisting of 748 patients, the mean ABSI-score was 5.6 (+/- 2.7 SD). A mean of 16.5 percent (+/- 10.1 SD) body surface area was burned. Treatment required a median of 3 days on the burn ICU (range 1-120). Regarding these parameters, the burden of disease was comparable in both groups., Conclusion: Bioethanol-fueled fireplaces for interior home decoration are a potential source for severe burn accidents even by intended use., (Copyright © 2015 Elsevier Ltd and ISBI. All rights reserved.)

Background: Complex peripheral nerve injuries of the hand include at least 300,000 cases per year in Europe. The standard treatment involves a microsurgical end-to-end suture of traumatic sensory nerve lesions of the hand without a gap. The objective of this study protocol is to evaluate whether the additional use of a chitosan nerve tube in primary repair of traumatic sensory nerve lesions of the hand without a gap has an effect on the recovery of sensitivity., Methods/design: We planned a randomized double-blind controlled multicenter trial with a parallel group design in order to show superiority for the additional use of a chitosan nerve tube. This study will enroll 100 participants with traumatic sensory nerve lesions of the hand without a gap from three Trauma Care Centers. Participants will be randomized in a 1:1 ratio to primary microsurgical repair of the injured nerve with the additional use of a chitosan nerve tube or direct tension free microsurgical repair of the injured nerve alone. The static two-point discrimination of the injured finger after 6 months will be the primary outcome parameter., Discussion: In the proposed study, the additional use of a chitosan nerve tube for a primary microsurgical repair of traumatic sensory nerve lesions of the hand without a gap will be evaluated in a prospective randomized double-blind controlled multicenter trial for the first time to create the highest possible evidence for the procedure., Trial Registration: ClinicalTrials.gov Identifier: NCT02372669 . Protocol Registration Receipt on 27 February 2015.

We report on the impact of the differing spectral near- and far-field properties of resonantly excited gold nanoantennas on the vibrational signal enhancement in surface-enhanced infrared absorption (SEIRA). The knowledge on both spectral characteristics is of considerable importance for the optimization of plasmonic nanostructures for surface-enhanced spectroscopy techniques. From infrared micro-spectroscopic measurements, we simultaneously obtain spectral information on the plasmonic far-field response and, via SEIRA spectroscopy of a test molecule, on the near-field enhancement. The molecular test layer of 4,4'-bis(N-carbazolyl)-1,1'-biphenyl (CBP) was deposited on the surface of gold nanoantennas with different lengths and thus different far-field resonance energies. We carefully studied the Fano-type vibrational lines in a broad spectral window, in particular, how the various vibrational signals are enhanced in relation to the ratio of the far-field plasmonic resonance and the molecular vibrational frequencies. As a detailed experimental proof of former simulation studies, we show the clearly red-shifted maximum SEIRA enhancement compared to the far-field resonance.

A switchable perfect absorber with multispectral thermal imaging capability is presented. Aluminum nanoantenna arrays above a germanium antimony telluride (GST) spacer layer and aluminum mirror provide efficient wavelength-tunable absorption in the mid-infrared. Utilizing the amorphous-to-crystalline phase transition in GST, this device offers switchable absorption with strong reflectance contrast at resonance and large phase-change-induced spectral shifts., (© 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

In this paper, we present the design and fabrication of a plasmonic metasurface based on titanium dioxide (TiO2) nanowire arrays integrated with plasmonic layers. The structure is engineered to produce Fano resonances within the visible spectrum, resulting from the coupling of localized surface plasmon resonances, lattice modes, and nanowire's optical modes. Experimentally, we show that by tuning the geometrical features of the metasurface, such as the length, diameter, and period of the nanowires, a high-quality factor single peak can be achieved in the reflection spectra, resulting in vivid structural colors in bright field. To our knowledge, this is the first demonstration of such vivid colors with nanowire arrays in bright field reflections. When characterized by refractive index fluids around the refractive index of water, the plasmonic metasurface also showed great potential for biochemical colorimetric sensing. The best design demonstrated a bulk sensitivity of 183 nm/RIU with high Q resonance features and linear changes in color values using image processing. [ABSTRACT FROM AUTHOR]

Developing switchable and multifunctional metasurfaces is essential for high-integration photonics. However, most previous studies encountered challenges such as limited degrees of freedom, simple tuning of predefined functionality, and complicated control systems. Here, we develop a general strategy to construct switchable and multifunctional metasurfaces. Two spin-modulated wave-controls are enabled by the proposed high-efficiency metasurface, which is designed using both resonant and geometric phases. Furthermore, the switchable wavefront tailoring can also be achieved by flexibly altering the lattice constant and reforming the phase retardation of the metasurfaces based on the "rotating square" (RS) kirigami technique. As a proof of concept, a kirigami metasurface is designed that successfully demonstrates dynamic controls of three-channel beam steering. In addition, another kirigami metasurface is built for realizing tri-channel complex wavefront engineering, including straight beam focusing, tilted beam focusing, and anomalous reflection. By altering the polarization of input waves as well as transformation states, the functionality of the metadevice can be switched flexibly among three different channels. Microwave experiments show good agreement with full-wave simulations, clearly demonstrating the performance of the metadevices. This strategy exhibits advantages such as flexible control, low cost, and multiple and switchable functionalities, providing a new pathway for achieving switchable wavefront engineering. [ABSTRACT FROM AUTHOR]