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The first, to our knowledge, passive, precision, self- alignment technique for direct coupling of vertical cavity surface emitting laser (VCSEL) and photodiode (PD) arrays to an array of polymer buried channel waveguides on a rigid printed circuit board (PCB) is reported. It gives insertion losses as good as the best achieved previously, to within experimental measurement accuracy, but without the need for costly active alignment nor waveguide facet polishing and so is a major step towards a commercially realizable low cost connector. Such an optical connector with four duplex channels each operating at 10 Gb/s (80 Gb/s aggregate) was designed, constructed, and its alignment precision assessed. The alignment technique is applicable to polymer waveguide interconnections on both rigid and flexible multilayer printed circuit boards (PCBs). The dependence of optical coupling loss on misalignments in x, y and z of the VCSEL and PD arrays allows the precision of alignment to be assessed and its reproducibility on multiple mating cycles of the connector is reported. The first recorded measurements of crosstalk between waveguides when the connector is misaligned are reported. Lateral misalignments of the connector to within its tolerance are shown to have no effect on the signal to crosstalk ratio (SCR), to within experimental measurement accuracy. The insertion loss repeatability is similar to that of single mode fiber mechanically transferable (MT) connectors. [ABSTRACT FROM AUTHOR]

The authors have identified a typographical error in their manuscript on page 3591. The inter planar spacing for the (101) plane of anatase TiO SB 2 sb is stated to be measured as 0.32 nm; however, it should be 0.35 nm. The authors apologize for this oversight and for any inconvenience caused.... Further characterization with HR-TEM revealed that the metal salt modifications did not induce any changes in the inter planar spacing as it was measured to be B 0.35 nm b corresponding to the (101) plane of the anatase TiO2 (insets of Figure 1 (b), (d) and (f) respectively). [Extracted from the article]

Carbon nanotubes are shown to be beneficial additives to perovskite solar cells, and the inclusion of such nanomaterials will continue to play a crucial role in the push toward developing efficient and stable device architectures. Herein, titanium dioxide/carbon nanotube composite perovskite solar cells are fabricated, and device performance parameters are correlated with spectroscopic signatures of the materials to understand the origin of performance enhancement. By probing the charge carrier dynamics with photoluminescence and femtosecond transient absorption spectroscopy, the results indicate that charge transfer is not improved by the presence of the carbon nanotubes. Instead, carbon nanotubes are shown to passivate the electronic defect states within the titanium dioxide, which can lead to stronger radiative recombination in the titanium dioxide/carbon nanotube films. The defect passivation allows the perovskite solar cells made using an optimized titanium dioxide/carbon nanotube composite to achieve a peak power conversion efficiency of 20.4% (19% stabilized), which is one of the highest values reported for perovskite solar cells not incorporating a mixed cation light absorbing layer. The results discuss new fundamental understandings for the role of carbon nanomaterials in perovskite solar cells and present a significant step forward in advancing the field of high‐performance photovoltaics. [ABSTRACT FROM AUTHOR]

Organic VLC is an emerging subset of visible light communications that uses organic photonic components as the link transmitter, receiver or both. Recent developments in organic LEDs have enabled high efficiency and brightness devices that can be used for data transmission as in conventional VLC systems. VLC utilizes the visible wavelength range of the electromagnetic spectrum (370?780 nm). Here we demonstrate an organic VLC link using an OLED with 93 kHz bandwidth as the source and a silicon photodetector with 5 MHz bandwidth and a 10 dB gain as the receiver. A wide range of modulation schemes are examined; and, as is commonplace in communications systems, equalization techniques are implemented to maximize data rates into the megabits per second region, and 2.7 Mb/s was achieved. [ABSTRACT FROM AUTHOR]

The thermodynamics and kinetics of the structural phase transition from monoclinic VO 2 (M) to rutile VO 2 (R) and vice versa were studied for particulate materials obtained by bead milling of VO 2 (M) powder. Using wet bead milling, we decreased the particle size of VO 2 (M) powder from ∼1 μm to 129 nm. With progressive milling, the switching enthalpy decreased from 47 J g−1 to 29 J g−1 due to a loss of crystallinity. The switching kinetics were studied using Friedman's differential isoconversional method. The activation energy | E α | decreases with increasing difference between the actual temperature of the material and its switching temperature (T 0). Furthermore, | E α | decreases with progressive milling, and kinetic asymmetry is induced. For milled particulate materials, | E α | is lower for the switch from VO 2 (R) to VO 2 (M) than for the opposite switch. For hydrothermally synthesized nanoparticles, | E α | is in the same order of magnitude, albeit with inverse switching asymmetry. Latter may result from different defects that are introduced during both preparation techniques. Applying layers of milled particulate material to glass sheets yielded thermochromic coatings with luminous transmission of 40.7% and solar modulation of 8.3%. This demonstrates that milled VO 2 particles have potential for use in energy efficient thermochromic windows. [Display omitted] • Switching enthalpy of VO 2 particulate material decreases with progressive milling. • Activation energy of the structural phase transition decreases with particle size. • Progressive milling induces asymmetry in switching kinetics of particulate material. • Hydrothermally synthesized particles display inverse asymmetry in kinetics. • Milled VO 2 particulate materials are suited for use in thermochromic windows. [ABSTRACT FROM AUTHOR]

CD56 or neural cell adhesion molecule (NCAM) is a membrane glycoprotein expressed on neural cells, muscle tissues and myeloma cells. Expression of CD56 has been studied in patients with multiple myeloma (MM) with controversial results. The scope of this study was to examine the expression of CD56 in MM patients at diagnosis and investigate its association with clinicopathologic parameters. We retrospectively collected and analyzed data from 109 patients with MM diagnosed over the last decade (January 2010 to June 2020). Expression of CD56 was assessed by immunohistochemistry in bone marrow biopsies and investigated its association with a variety of clinicopathological parameters. For the statistical analysis χ2 test and Mann-Whitney U tests were used to compare categorical and continuous variables in CD56+ and CD56- patients, respectively. Statistical analysis was performed using SPSS 21.0 for Windows (SPSS, Chicago, IL). Based on the expression of CD56 the patient population was divided to CD56+ patients and CD56- patients; Sixty-eight patients were CD56 + and 41 patients were CD56–. Absence of CD56 expression was associated with unfavorable prognostic parameters such as elevated lactate dehydrogenase (LDH) and β2-microglobulin levels, advanced stage according to the International Staging System (ISS) and clonal bone marrow plasma cell infiltration ≥ 60%, but no effect on outcome, while the expression of CD56 was associated with well differentiated neoplastic plasma cells. Our study confirmed that lack of CD56 expression is a possible marker of poor prognosis in patients with MM. The detection of CD56 expression by either immunohistochemistry or flow cytometry is simple and cheap, and it could be incorporated in future prognostic or predictive scores. Prospective studies are needed in order to evaluate the role of expression of CD56 as a predictive biomarker in the era of novel regimens. [ABSTRACT FROM AUTHOR]

Thermochromic vanadium dioxide (VO 2) window coatings hold the promise of reducing the energy consumption of the built environment by passively regulating solar heat gain in response to changing conditions. Composite materials with embedded VO 2 particles have shown greatly improved optical performances compared with thin films, however they typically exhibit broadened phase transition hysteresis and gradient widths, which negatively impacts the overall performance. Here, we present a scalable one-step solution based synthesis for a thermochromic smart window coating based on a vanadium dioxide sol-gel containing silica (SiO 2 nanoparticles. We compare the performance of our nanoparticle composite with thin film VO 2 along with composites formed by mixing VO 2 and SiO 2 sol-gels and find that both composites achieve an acceptable visible transmittance (∼ 50%) along with a comparable and competitive solar modulation (12.5% and 16.8% respectively), roughly double that of the plain VO 2 film (6.7%). However, our SiO 2 nanoparticle containing composite also benefits from a narrow transition hysteresis and gradient width (9.4 ∘C and 2.9 ∘C respectively). We predict that this method may subsequently be combined with metal ion doping to control both the optical and phase transition characteristics to achieve composite films with high overall energy saving performances. • Improved visible transmittance due to reduced visible reflectivity. • SiO 2 particles act as a matrix for VO2 domain growth. • VO 2 domains grow larger and are more uniform in size. • Narrow hysteresis and transition gradient for improved overall performance. [ABSTRACT FROM AUTHOR]

Slippery lubricant infused porous surfaces (SLIPS) have the potential to address daunting challenges such as undesirable surface fouling/biofouling, icing, etc. However, the depletion of lubricants hampers their practical utility. As a solution, here a rational strategy is introduced that operates synergistically in three parts. First, ultra-high capillary pressure is exploited from the reticular structure of metal-organic frameworks (MOFs) with sub-nanometer pores. Second, the need for geometric compatibility is demonstrated; the lubricant chain diameter must be smaller than the MOF pore to enable lubricant chain intercalation. Lastly, the MOF pore chemistry is tailored to achieve a strong intermolecular interaction for any given MOF/lubricant combination. The strategy is investigated through experiments and quantum/molecular simulations, which show that the approach helps lock the intercalated lubricant chains inside the MOF pores and forms a non-conventional supramolecular structure. The resulting SLIPS (including those with fluorine-free chemistry) not only show typical low wetting hysteresis, friction, and ice adhesion but are uniquely resistant to more stringent tests such as continuous dripping and sliding of water droplets (up to 50 hrs), repeated impacts of high-speed water jets (liquid impact Weber number > 4 × 10 4 ) and prevent bacterial biofilm formation even in dynamic flow conditions. The findings may widen the practical applications of SLIPS., (© 2024 The Author(s). Advanced Materials published by Wiley‐VCH GmbH.)

Self-adaptive thermoregulation, the mechanism living organisms use to balance their temperature, holds great promise for decarbonizing cooling and heating processes. This functionality can be effectively emulated by engineering the thermal emissivity of materials to adapt to background temperature variations. Yet, solutions that marry large emissivity switching ( Δ ϵ ) with scalability, cost-effectiveness, and design freedom are still lacking. Here, we fill this gap by introducing infrared dipole antennas made of tunable thermochromic materials. We demonstrate that non-spherical antennas (rods, stars and flakes) made of vanadium-dioxide can exhibit a massive (~200-fold) increase in their absorption cross-section as temperature rises. Embedding these antennas in polymer films, or simply spraying them directly, creates free-form thermoregulation composites, featuring an outstanding Δ ϵ ~ 0.6 in spectral ranges that can be tuned at will. Our research paves the way for versatile self-adaptive heat management solutions (coatings, fibers, membranes, and films) that could find application in radiative-cooling, heat-sensing, thermal-camouflage, and other., (© 2024. The Author(s).)

Accurate oxygen sensing and cost-effective fabrication are crucial for the adoption of wearable devices inside and outside the clinical setting. Here we introduce a simple strategy to create nonwoven polymeric fibrous mats for a notable contribution towards addressing this need. Although morphological manipulation of polymers for cell culture proliferation is commonplace, especially in the field of regenerative medicine, non-woven structures have not been used for oxygen sensing. We used an airbrush spraying, i.e. solution blowing, to obtain nonwoven fiber meshes embedded with a phosphorescent dye. The fibers serve as a polymer host for the phosphorescent dye and are shown to be non-cytotoxic. Different composite fibrous meshes were prepared and favorable mechanical and oxygen-sensing properties were demonstrated. A Young's modulus of 9.8 MPa was achieved and the maximum oxygen sensitivity improved by a factor of ∼2.9 compared to simple drop cast film. The fibers were also coated with silicone rubbers to produce mechanically robust sensing films. This reduced the sensing performance but improved flexibility and mechanical properties. Lastly, we are able to capture oxygen concentration maps via colorimetry using a smartphone camera, which should offer unique advantages in wider usage. Overall, the introduced composite fiber meshes show a potential to significantly improve cell cultures and healthcare monitoring via absolute oxygen sensing., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Author(s). Published by Elsevier B.V. All rights reserved.)

Optimizing the photon spectrum for photosynthesis concurrently with improving crop yields presents an efficient and sustainable pathway to alleviate global food shortages. Luminescent solar concentrators (LSCs), consisting of transparent host matrices doped with fluorophores, show excellent promise to achieve the desired spectral tailoring. However, conventional LSCs are predominantly engineered for photon concentration, which results in a limited outcoupling efficiency of converted photons. Here, we introduce a scheme to implement LSCs into horticulture (HLSC) by enhancing light extraction. The symmetry of the device is disrupted by incorporating microcone arrays on the bottom surface to mitigate total internal reflection. Both Monte Carlo ray tracing simulations and experimental results have verified that the greatest enhancements in converted light extraction, relative to planar LSCs, are achieved using microcone arrays (base width 50 μm, aspect ratio 1.2) with extruded and protruded profiles (85.15 and 66.55% improvement, respectively). Angularly resolved transmission measurements show that the HLSC device exhibits a broad angular radiation distribution. This characteristic indicates that the HLSC device emits diffuse light, which is conducive to optimal plant growth.

Background: Total proctocolectomy (TPC) followed by ileal pouch-anal anastomosis (IPAA) remains the only viable option whenever different treatment modalities fail in patients with ulcerative colitis (UC)., Objective: Prospective cohort pre/post study examining the anal defecatory function and competence in UC patients undergoing TPC plus IPAA using high-resolution anorectal manometry (HR-ARM)., Patients: Patients undergoing TPC and IPAA were enrolled in the study and subjected to HR-ARM prior to and 6 months after surgery. The anal resting, squeeze and push pressures were recorded, together with the rectal sensation and the rectal balloon expulsion test. The number of bowel movements, symptoms/signs related to fecal incontinence, as well as the IBDQ-32 quality of life questionnaires were documented during both HR-ARM visits., Results: A total of 20 consecutive UC patients were recruited in our study. The mean (SD) number of bowel movements before the TPC plus IPAA was 10.1 (2.8), while the same number after the pouch surgery was 7.7 (3.1) [ P  = 0.01]. Symptoms or signs of fecal incontinence were noted in one of our patients prior to the operation; however, none of our patients reported any such symptoms after the pouch surgery. The median (IQR) IBDQ-32 questionnaire scores before and after surgery were 121.5 (13.5) and 142.5 (16.0) respectively. At the same time, the anorectal function remained intact since both the anal resting and squeeze pressures were not significantly changed., Conclusion: UC patients subjected to TPC-IPAA exhibit improved bowel movements and a normal anal defecatory function and competence post-surgery., (Copyright © 2023 Wolters Kluwer Health, Inc. All rights reserved.)

Whilst it is now well recognized that some natural surfaces such as seemingly fragile insect wings possess extraordinary antimicrobial properties, a quest to engineer similar nanopatterned surfaces (NPSs) is ongoing. The stake is high as biofouling impacts critical infrastructure leading to massive social and economic burden with an antimicrobial resistance (AMR) issue at the forefront. AMR is one of the most imminent health challenges the world is facing today. Here, in the effort to find more sustainable solutions, the NPSs are proposed as highly promising technology as their antimicrobial activity arises from the topographical features, which could be realized on multiple material surfaces. To fully exploit these potentials however, it is crucial to mechanistically understand the underlying killing pathways. Thus far, several mechanisms have been proposed, yet they all have one thing in common. The antimicrobial process is initiated with bacteria contacting nanopatterns, which then imposes mechanical stress onto bacterial cell wall. Hence, the activity is called "mechano-bactericidal". From this point on, however, the suggested mechanisms start to diverge partly due to our limited understanding of force interactions at the interface. The aim of this mini review is to analyze the state-of-the-art in proposed killing mechanisms by categorizing them based on the characteristics of their driving force. We also highlight the current gaps and possible future directions in investigating the mechanisms, particularly by shifting towards quantification of forces at play and more elaborated biochemical assays, which can aid validating the current hypotheses., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2024 Pirouz, Papakonstantinou and Michalska.)

Enzymatic electrochemical sensors have become the leading glucose detection technology due to their rapid response, affordability, portability, selectivity, and sensitivity. However, the performance of these sensors is highly dependent on the surface properties of the electrode material used to store glucose oxidase and its ability to retain enzymatic activity under variable environmental conditions. Mesoporous thin films have recently attracted considerable attention as promising candidates for enzyme storage and activity preservation due to their well-defined nanoarchitecture and tunable surface properties. Herein, we systematically compare pathways for the immobilization of glucose oxidase (GOx) and their effectiveness in electrochemical glucose sensing, following modification protocols that lead to the electrostatic attraction (amino functionalization), covalent bonding (aldehyde functionalization), and electrostatic repulsion (oxygen plasma treatment) of the ordered porous aluminosilicate-coated electrodes. By direct comparison using a quartz crystal microbalance, we demonstrate that glucose oxidase can be loaded in a nanoarchitecture with a pore size of ∼50 nm and pore interconnections of ∼35 nm using the native aluminosilicate surface, as well as after amino or aldehyde surface modification, while oxygen plasma exposure of the native surface inhibits glucose oxidase loading. Despite a variety of routes for enzyme loading, quantitative electrochemical glucose sensing between 0 and 20 mM was only possible when the porous surface was functionalized with amino groups, which we relate to the role of surface chemistry in accessing the underlying substrate. Our results highlight the impact of rational surface modification on electrochemical biosensing performance and demonstrate the potential of tailoring porous nanoarchitecture surfaces for biosensing applications., Competing Interests: The authors declare no competing financial interest., (© 2023 The Authors. Published by American Chemical Society.)

The electrochemical synthesis of hydrogen peroxide (H 2 O 2 ) via a two-electron (2 e - ) oxygen reduction reaction (ORR) process provides a promising alternative to replace the energy-intensive anthraquinone process. Herein, we develop a facile template-protected strategy to synthesize a highly active quinone-rich porous carbon catalyst for H 2 O 2 electrochemical production. The optimized PCC 900 material exhibits remarkable activity and selectivity, of which the onset potential reaches 0.83 V vs. reversible hydrogen electrode in 0.1 M KOH and the H 2 O 2 selectivity is over 95 % in a wide potential range. Comprehensive synchrotron-based near-edge X-ray absorption fine structure (NEXAFS) spectroscopy combined with electrocatalytic characterizations reveals the positive correlation between quinone content and 2 e - ORR performance. The effectiveness of chair-form quinone groups as the most efficient active sites is highlighted by the molecule-mimic strategy and theoretical analysis., (© 2023 The Authors. Angewandte Chemie International Edition published by Wiley-VCH GmbH.)

Fiber-optic hydrophones (FOHs) are widely used to detect high-intensity focused ultrasound (HIFU) fields. The most common type consists of an uncoated single-mode fiber with a perpendicularly cleaved end face. The main disadvantage of these hydrophones is their low signal-to-noise ratio (SNR). To increase the SNR, signal averaging is performed, but the associated increased acquisition times hinder ultrasound field scans. In this study, with a view to increasing SNR while withstanding HIFU pressures, the bare FOH paradigm is extended to include a partially reflective coating on the fiber end face. Here, a numerical model based on the general transfer-matrix method was implemented. Based on the simulation results, a single-layer, 172 nm TiO 2 -coated FOH was fabricated. The frequency range of the hydrophone was verified from 1 to 30 MHz. The SNR of the acoustic measurement with the coated sensor was 21 dB higher than that of the uncoated one. The coated sensor successfully withstood a peak positive pressure of 35 MPa for 6000 pulses.

Luminescent solar concentrators (LSCs) have shown the ability to realize spectral conversion, which could tailor the solar spectrum to better match photosynthesis requirements. However, conventional LSCs are designed to trap, rather than extract, spectrally converted light. Here, we propose an effective method for improving outcoupling efficiency based on protruded and extruded micro-cone arrays patterned on the bottom surface of LSCs. Using Monte Carlo ray tracing, we estimate a maximum external quantum efficiency (EQE) of 37.73% for our horticulture LSC (HLSC), corresponding to 53.78% improvement relative to conventional, planar LSCs. Additionally, structured HLSCs provide diffuse light, which is beneficial for plant growth. Our micro-patterned surfaces provide a solution to light trapping in LSCs and a foundation for the practical application of HLSCs.

Absolute oxygen sensors based on quenching of phosphorescence have been the subject of numerous studies for the monitoring of biological environments. Here, we used simple fabrication techniques with readily available polymers to obtain high performance phosphorescent films. Specifically, evaporation-based phase separation and the breath figure technique were used to induce porosity. The pore sizes ranged from ∼ 37 nm to ∼ 141 μ m while the maximum average porosity achieved was ∼ 74%. The oxygen sensing properties were evaluated via a standarised calibration procedure with an optoelectronic setup in both transmission and reflection based configurations. When comparing non-porous and porous films, the highest improvements achieved were a factor of ∼ 7.9 in dynamic range and ∼ 7.3 in maximum sensitivity, followed by an improved linearity with a half-sensitivity point at 43% O 2 V/V. Also, the recovery time was reduced by an order of magnitude in the high porosity film and all samples prepared were not affected by variations in the humidity of the surrounding environment. Despite the use of common polymers, the fabrication techniques employed led to the significant enhancement of oxygen sensing properties and elucidated the relation between porous film morphologies and sensing performance., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© 2022 The Authors.)

Silicon nanostructuring imparts unique material properties including antireflectivity, antifogging, anti-icing, self-cleaning, and/or antimicrobial activity. To tune these properties however, a good control over features' size and shape is essential. Here, a versatile fabrication process is presented to achieve tailored silicon nanostructures (thin/thick pillars, sharp/truncated/re-entrant cones), of pitch down to ∼50 nm, and high-aspect ratio (>10). The approach relies on pre-assembled block copolymer (BCP) micelles and their direct transfer into a glass hard mask of an arbitrary thickness, now enabled by our recently reported regenerative secondary mask lithography. During this pattern transfer, not only can the mask diameter be decreased but also uniquely increased, constituting the first method to achieve such tunability without necessitating a different molecular weight BCP. Consequently, the hard mask modulation (height, diameter) advances the flexibility in attainable inter-pillar spacing, aspect ratios, and re-entrant profiles (= glass on silicon). Combined with adjusted silicon etch conditions, the morphology of nanopatterns can be highly customized. The process control and scalability enable uniform patterning of a 6-inch wafer which is verified through cross-wafer excellent antireflectivity (<5%) and water-repellency (advancing contact angle 158°; hysteresis 1°). The implementation of this approach to silicon nanostructuring is envisioned to be far-reaching, facilitating fundamental studies and targeting applications spanning solar panels, antifogging/antibacterial surfaces, sensing, amongst many others.

Nature-inspired nanopatterning offers exciting multifunctionality spanning antireflectance and the ability to repel water/fog, oils, and bacteria; strongly dependent upon nanofeature size and morphology. However, such patterning in glass is notoriously difficult, paradoxically, due to the same outstanding chemical and thermal stability that make glass so attractive. Here, regenerative secondary mask lithography is introduced and exploited to enable customized glass nanopillars through dynamic nanoscale tunability of the side-wall profile and aspect ratio (>7). The method is simple and versatile, comprising just two steps. First, sub-wavelength scalable soft etch masks (55-350 nm) are generated through an example of block copolymer micelles or nanoimprinted photoresist. Second, their inherent durability problem is addressed by an innovative cyclic etching, when the original mask becomes embedded within a protective secondary organic mask, which is tuned and regenerated, permitting dynamic nanofeature profiling with etching selectivity >1:32. It is envisioned that such structuring in glass will facilitate fundamental studies and be useful for numerous practical applications-from displays to architectural windows. To showcase the potential, glass features are tailored to achieve excellent broadband omnidirectional antireflectivity, self-cleaning, and unique antibacterial activity toward Staphylococcus aureus., (© 2021 The Authors. Advanced Materials published by Wiley-VCH GmbH.)

Slippery liquid infused porous surfaces (SLIPS) are an important class of repellent materials, comprising micro/nanotextures infused with a lubricating liquid. Unlike superhydrophobic surfaces, SLIPS do not rely on a stable air-liquid interface and thus can better manage low surface tension fluids, are less susceptible to damage under physical stress, and are able to self-heal. However, these collective properties are only efficient as long as the lubricant remains infused, which has proved challenging. We hypothesized that, in comparison to a nanohole and nanopillar morphology, the "hybrid" morphology of a hole within a nanopillar, namely a nanotube, would be able to retain and redistribute lubricant more effectively, owing to capillary forces trapping a reservoir of lubricant within the tube, while lubricant between tubes can facilitate redistribution to depleted areas. By virtue of recent fabrication advances in spacer defined intrinsic multiple patterning (SDIMP), we fabricated an array of silicon nanotubes and equivalent arrays of nanoholes and nanopillars (pitch, 560 nm; height, 2 μm). After infusing the nanostructures (prerendered hydrophobic) with lubricant Krytox 1525, we probed the lubricant stability under dynamic conditions and correlated the degree of the lubricant film discontinuity to changes in the contact angle hysteresis. As a proof of concept, the durability test, which involved consecutive deposition of droplets onto the surface amounting to 0.5 L, revealed 2-fold and 1.5-fold enhancements of lubricant retention in nanotubes in comparison to nanopillars and nanoholes, respectively, showing a clear trajectory for prolonging the lifetime of a slippery surface.

Background: Hepatic dysfunction in patients with classical Hodgkin lymphoma (cHL) is of multifactorial aetiology. Prompt evaluation with laboratory tests and imaging methods is sufficient for diagnosis in most cases. Intrahepatic cholestasis and vanishing bile duct syndrome (VBDS) may complicate cHL as rare paraneoplastic phenomena. Liver biopsy provides crucial evidence of cholestasis, and ductopenia, if present, confirms the diagnosis of VBDS., Case Report: We report on a cHL patient that presented with jaundice and bulky mediastinal disease and unfold the therapeutic dilemmas we confronted. Marked hyperbilirubinemia was successfully reversed with brentuximab vedotin (BV) at a dose of 1.2 mg/kg and the patient was subsequently treated with doxorubicin, bleomycin, vinblastine and dacarbazine (ABVD) at full doses, achieving complete metabolic response. A literature review of intrahepatic cholestasis in cHL is also presented based on currently available data with focus on treatment options and clinicopathologic associations., Conclusion: VBDS and intrahepatic cholestasis are rare and potentially fatal complications of cHL. Their prompt recognition and appropriate treatment can dramatically affect cHL patients' outcome. BV, used at a reduced dose as a bridging therapy, should be considered as a high-priority treatment plan in these challenging cases., (Copyright © 2021 International Institute of Anticancer Research (Dr. George J. Delinasios), All rights reserved.)

Surface structuring provides a broad range of water-repellent materials known for their ability to reflect millimetre-sized raindrops. Dispelling water at the considerably reduced scale of fog or dew, however, constitutes a significant challenge, owing to the comparable size of droplets and structures. Nonetheless, a surface comprising nanocones was recently reported to exhibit strong anti-fogging behaviour, unlike pillars of the same size. To elucidate the origin of these differences, we systematically compare families of nanotexture that transition from pillars to sharp cones. Through environmental electron microscopy and modelling, we show that microdroplets condensing on sharp cones adopt a highly non-adhesive state, even at radii as low as 1.5 µm, contrasting with the behaviour on pillars where pinning results in impedance of droplet ejection. We establish the antifogging abilities to be universal over the range of our cone geometries, which speaks to the unique character of the nanocone geometry to repel dew. Truncated cones are finally shown to provide both pinning and a high degree of hydrophobicity, opposing characteristics that lead to a different, yet efficient, mechanism of dew ejection that relies on multiple coalescences.

Small form-factor sensors are widely used in minimally invasive intravascular diagnostic procedures. Manufacturing complexities associated with miniaturizing current fiber-optic probes, particularly for multi-parameter sensing, severely constrain their adoption outside of niche fields. It is especially challenging to rapidly prototype and iterate upon sensor designs to optimize performance for medical devices. In this work, a novel technique to construct a microscale extrinsic fiber-optic sensor with a confined air cavity and sub-micron geometric resolution is presented. The confined air cavity is enclosed between a 3 μm thick pressure-sensitive distal diaphragm and a proximal temperature-sensitive plano-convex microlens segment unresponsive to changes in external pressure. Simultaneous pressure and temperature measurements are possible through optical interrogation via phase-resolved low-coherence interferometry (LCI). Upon characterization in a simulated intravascular environment, we find these sensors capable of detecting pressure changes down to 0.11 mmHg (in the range of 760 to 1060 mmHg) and temperature changes of 0.036 °C (in the range 34 to 50 °C). By virtue of these sensitivity values suited to intravascular physiological monitoring, and the scope of design flexibility enabled by the precision-fabricated photoresist microstructure, it is envisaged that this technique will enable construction of a wide range of fiber-optic sensors for guiding minimally invasive medical procedures.

Luminescent solar concentrators (LSCs) have recently emerged as a promising receiver technology in free-space optical communications due to their inherent ability to collect light from a wide field-of-view and concentrate it into small areas, thus leading to high optical gains. Several high-speed communication systems integrating LSCs in their detector blocks have already been demonstrated, with the majority of efforts so far being devoted to maximising the received optical power and the system's field-of-view. However, LSCs may pose a severe bottleneck on the bandwidth of such communication channels due to the comparably slow timescale of the fluorescence events involved, a situation further aggravated by the inherent reabsorption in these systems, and yet, an in-depth study into such dynamic effects remains absent in the field. To fill this gap, we have developed a comprehensive analytical solution that delineates the fundamental bandwidth limits of LSCs as optical detectors in arbitrary free-space optical links, and establishes their equivalence with simple RC low-pass electrical circuits. Furthermore, we demonstrate a time-domain Monte Carlo simulation platform, an indispensable tool in the multiparameter optimisation of LSC-based receiver systems. Our work offers vital insight into LSC system dynamic behaviour and paves the way to evaluate the technology for a wide range of applications, including visible light communications, high-speed video recording, and real-time biological imaging, to name a few.

In recent decades, there has been a growing interest in the development of functional, fluorine-free superhydrophobic surfaces with improved adhesion for better applicability into real-world problems. Here, we compare two different methods, spin coating and aerosol-assisted chemical vapor deposition (AACVD), for the synthesis of transparent fluorine-free superhydrophobic coatings. The material was made from a nanocomposite of (3-aminopropyl)triethoxysilane (APTES) functional mesoporous silica nanoparticles and titanium cross-linked polydimethylsiloxane with particle concentrations between 9 to 50 wt %. The silane that was used to lower the surface energy consisted of a long hydrocarbon chain without fluorine groups to reduce the environmental impact of the composite coating. Both spin coating and AACVD resulted in the formation of superhydrophobic surfaces with advancing contact angles up to 168°, a hysteresis of 3°, and a transparency of 90% at 550 nm. AACVD has proven to produce more uniform coatings with concentrations as low as 9 wt %, reaching superhydrophobicity. The metal oxide cross-linking improves the adhesion of the coating to the glass. Overall, AACVD was the more optimal method to prepare superhydrophobic coatings compared to spin coating due to higher contact angles, adhesion, and scalability of the fabrication process.

Miniaturised high-resolution imaging devices are valuable for guiding minimally invasive procedures such as vascular stent placements. Here, we present all-optical rotational B-mode pulse-echo ultrasound imaging. With this device, ultrasound transmission and reception are performed with light. The all-optical transducer in the probe comprised an optical fibre that delivered pulsed excitation light to an optical head at the distal end with a multi-walled carbon nanotube and polydimethylsiloxane composite coating. This coating was photoacoustically excited to generate a highly directional ultrasound beam perpendicular to the optical fibre axis. A concave Fabry-Pérot cavity at the distal end of an optical fibre, which was interrogated with a tuneable continuous-wave laser, served as an omnidirectional ultrasound receiver. The transmitted ultrasound had a -6 dB bandwidth of 31.3 MHz and a peak-to-peak pressure of 1.87 MPa, as measured at 1.5 mm from the probe. The receiver had a noise equivalent pressure <100 Pa over a 20 MHz bandwidth. With a maximum outer probe diameter of 1.25 mm, the probe provided imaging with an axial resolution better than 50 µm, and a real-time imaging rate of 5 frames per second. To investigate the capabilities of the probe, intraluminal imaging was performed in healthy swine carotid arteries. The results demonstrate that the all-optical probe is viable for clinical rotational ultrasound imaging.

The aim of thermochromic window coatings is to reduce the energy consumption in the built environment by passively switching between a high solar transmitting state at low temperatures and low solar transmitting state at high temperatures. Previous studies have highlighted the negative impact of phase transition hysteresis on the performance of reflection based thermochromic films. However in the literature, the best reported results have depended on vanadium dioxide nanoparticle composites and anti-reflective structures that modulate light via changes in absorption rather than reflection. In light of these factors, this work aims to demonstrate theoretically, how the effects of phase transition hysteresis and gradient differ between absorbing and non-absorbing thermochromic films. To quantify and compare the performance of films with different transition characteristics, we define a metric based on the varying net energy flux through the window over the course of a year, including thermal energy re-radiated into the building from the film. Specifically, and importantly for the field, we demonstrate that a pseudo-photochromic effect in absorbing thermochromic films mitigates the detrimental effects of phase transition hysteresis and gradient that have been reported for reflection based thermochromic films. We find that for moderate hysteresis widths of 15 °C, the performance of the non-absorbing case drops to ~60% of its initial value whilst the performance of the absorbing film only drops to ~95%. As a result we find that the absorbing case outperforms the non-absorbing case when hysteresis widths are greater than 8 °C.

Surface-enhanced Raman spectroscopy (SERS) has been widely utilised as a sensitive analytical technique for the detection of trace levels of organic molecules. The detection of organic compounds in the gas phase is particularly challenging due to the low concentration of adsorbed molecules on the surface of the SERS substrate. This is particularly the case for explosive materials, which typically have very low vapour pressures, limiting the use of SERS for their identification. In this work, silver nanocubes (AgNCs) were developed as a highly sensitive SERS substrate with very low limit-of-detection (LOD) for explosive materials down to the femtomolar (10 -15 M) range. Unlike typical gold-based nanostructures, the AgNCs were found suitable for the detection of both aromatic and aliphatic explosives, enabling detection with high specificity at low concentration. SERS studies were first carried out using a model analyte, Rhodamine-6G (Rh-6G), as a probe molecule. The SERS enhancement factor was estimated as 8.71 × 10 10 in this case. Further studies involved femtomolar concentrations of 2,4-dinitrotoluene (DNT) and nanomolar concentrations of 1,3,5-trinitroperhydro-1,3,5-triazine (RDX), as well as vapour phase detection of DNT.