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Abstract Using the flexibility and diversity of material and structure designs possible with 3D printing fiber technology, an all‐solid photonic crystal fiber (PCF) is fabricated using borate (B2O3) doping. The geometry, material, and optical properties of this 3D printed PCF are characterized and analyzed using optical microscopy, scanning electron microscopy (SEM), fiber index profilometry, and Fourier transform infrared (FTIR) microscopy. Analysis demonstrates that B2O3 doped in fabricated PCF has experienced evaporation leading to mass loss during drawing. In addition, there is no observable difference between the structure of substrate silica (SiO2) and the SiO2 nanoparticles. However, microdomain differences may explain enhanced reflectance. Furthermore, a Mach–Zehnder interferometer (MZI) sensor is constructed with this 3D printed solid PCF and applied to temperature, refractive index, tensile force, and bending sensing. The specially designed 3D printed PCF has maximum temperature sensitivity up to Δλ/ΔT ≈0.075 nm °C−1. When immersed in 76.34 wt.% glycerol‐water solution, the sensitivity can be further improved. These results demonstrate that 3D printing fiber technology enables the custom fabrication of highly sensitive optical fiber sensors, increasing opportunities for the development of diverse and flexible sensors and devices for future internet‐of‐things (IoT) applications.

Abstract Eagle syndrome is characterized by the presence of an abnormally elongated styloid process and has been related to different etiologies, including enthesitis, a known feature of spondyloarthropathies. We are describing a case of marked elongation of the styloid process in a patient with pre‐existing ankylosing spondylitis and associated enthesopathy.

The utilisation of plants directly as quantifiable natural sensors is proposed. A case study measuring surface wettability of Aucuba japonica, or Japanese Laurel, plants using a novel smartphone field interrogator is demonstrated. This plant has been naturalised globally from Asia. Top-down contact angle measurements map wettability on-site and characterise a range of properties impacting plant health, such as aging, solar and UV exposure, and pollution. Leaves at an early age or in the shadow of trees are found to be hydrophobic with contact angle θ ~ 99°, while more mature leaves under sunlight are hydrophilic with θ ~ 79°. Direct UVA irradiation at λ = 365 nm is shown to accelerate aging, changing contact angle of one leaf from slightly hydrophobic at θ ~ 91° to be hydrophilic with θ ~ 87° after 30 min. Leaves growing beside a road with heavy traffic are observed to be substantially hydrophilic, as low as θ ~ 47°, arising from increased wettability with particulate accumulation on the leaf surface. Away from the road, the contact angle increases as high as θ ~ 96°. The results demonstrate that contact angle measurements using a portable diagnostic IoT edge device can be taken into the field for environmental detection, pollution assessment and more. Using an Internet connected smartphone combined with a plant sensor allows multiple measurements at multiple locations together in real-time, potentially enabling tracking of parameter change anywhere where plants are present or introduced. This hybrid integration of widely distributed living organic systems with the Internet marks the beginning of a new bionic Internet-of-things (b-IoT).

To address climate change, environmental monitoring and wellness more generally on a global scale, a new concept is presented - the bionic internet-of-things, or b-IoT. We propose the utilization of existing organic “sensor” technology that nature has provided and discuss a future adapting these to an existing inorganic internet to truly open up a global IoT. The use of organisms, in the first instance plants, bring an additional physical and psychological factor, connecting up living in things in a way that is consistent with natural symbiosis but extended over a global and potentially galactic scale. These plants not only monitor the environment, they interact to enable it to thrive, producing an ecosystem that consumes CO2, generates oxygen, recycling land and providing an environment for other organic species to develop. In contemporary real estate development, the need for a more whole ecosystem approach is recognized and that technology plays a vital role towards that. Thus, we identify wellness and wellbeing as an integral part of all future technology development. A fundamental challenge is connecting such sensors to the IoT. We briefly review technologies of relevance in the context of material, health and environmental considerations, and discuss novel transducer mechanisms. To assess sensor capability, we review our recent work on measuring leaf material properties using contact angle mapping, demonstrating a diversity of potential for environmental monitoring from this method alone. We also review some examples of common botanical properties that already exist which can in principle be readily coupled to existing transducers to create the hybrid b-IoT. We briefly speculate into the future of materials at the sensor end and into reaching space that can meet low cost and provide advanced functionality to help connectivity and integrate fibre and fibreless technologies.

The SARS-Coronavirus-2 (SARS-CoV-2) infectious disease, COVID-19, has spread rapidly, resulting in a global pandemic with significant mortality. The combination of early diagnosis via rapid screening, contact tracing, social distancing and quarantine has helped to control the pandemic. The absence of real time response and diagnosis is a crucial technology shortfall and is a key reason why current contact tracing methods are inadequate to control spread. In contrast, current information technology combined with a new generation of near-real time tests offers consumer-engaged smartphone-based “lab-in-a-phone” internet-of-things (IoT) connected devices that provide increased pandemic monitoring. This review brings together key aspects required to create an entire global diagnostic ecosystem. Cross-disciplinary understanding and integration of both mechanisms and technologies for effective detection, incidence mapping and disease containment in near real-time is summarized. Available measures to monitor and/or sterilize surfaces, next-generation laboratory and smartphone-based diagnostic approaches can be brought together and networked for instant global monitoring that informs Public Health policy. Cloud-based analysis enabling real-time mapping will enable future pandemic control, drive the suppression and elimination of disease spread, saving millions of lives globally. A new paradigm is introduced – scaled and multiple diagnostics for mapping and spreading of a pandemic rather than traditional accumulation of individual measurements. This can do away with the need for ultra-precise and ultra-accurate analysis by taking mass measurements that can relax tolerances and build resilience through networked analytics and informatics, the basis for novel swarm diagnostics. These include addressing ethical standards, local, national and international collaborative engagement, multidisciplinary and analytical measurements and standards, and data handling and storage protocols.

Top-down contact angle (CA) measurements are used to characterize the green leaves and purple flowers of both old and young the Cattleya warneri orchids. The top-down CA allows the characterization of large surfaces away from the leaf edge, avoiding traditional cutting required for side view CA measurement. This allows large area mapping without damaging leaves making the method amenable to fieldwork and useful in environmental diagnostics. Young leaves are found to be hydrophobic whilst old leaves become practically hydrophilic across their entirety, mostly as a result of continued exposure to changes in the environment over time. The flowers are hydrophobic because of their visual and tactile attractor function for pollinating animals and the self-cleaning of dirt and pathogens. Real-time measurement and mapping of CA of surfaces open a new tool to assess the long-term impact of plant aging, pollution, and more of organisms in the field. The method has clear applications elsewhere such as in industrial probing of surfaces and products.

A fused deposition modeling (FDM) 3D printer extruder was utilized as a micro-furnace draw tower for the direct fabrication of low-cost optical fibers. An air-clad multimode microfiber was drawn from optically transparent polyethylene terephthalate glycol (PETG) filament. A custom-made spooling collection allows for an automatic variation of fiber diameter between ϕ ∼ 72 to 397 μm by tuning the drawing speed. Microstructure imaging as well as the 3D beam profiling of the transmitted beam in the orthogonal axes was used to show good quality, functioning microfiber fabrication with uniform diameter and identical beam profiles for orthogonal axes. The drawn microfiber was used to demonstrate budget smartphone colorimetric-based absorption measurement to detect the degree of adulteration of olive oils with soybean oil.

Fiber drawing from a 3D printed perform was recently discussed to go beyond the limitations of conventional optical fiber manufacturing in terms of structure and materials. In this work, the photosensitivity of silica optical fibers to femtosecond laser light, and fabricated by 3D printing a preform, is investigated. The writing kinetics and the thermal performance of Type II modifications are studied by varying the laser pulse energy and investigating the birefringence response of the femtosecond (fs)-laser written structures. Compared with a conventional telecom single mode fiber (SMF28), the fiber made by 3D printing is found to have similar writing kinetics and thermal performance. Additionally, the thermal stability of the imprinted fs-laser induced nanostructures is investigated based on the Rayleigh–Plesset equation, describing a model of nanopores dissolution underpinning Type II modifications with thermal annealing.

Social acceleration, the rapidly increasing speeding up of the pace of life, has been described and theorised by contemporary social theorists including Paul Virilio, Ben Agger, Thomas Hylland Eriksen, and Hartmut Rosa. While these theorists use illustrations from education, and others such as Foucault and Adam have considered the relationship between education and time, there has been little theorisation of dromology (a term Virilio coined to describe the 'science' of speed) in education studies itself. Given its growing importance as a 'grand theory' in social science, this paper calls for educationalists to recognise the value of theories of social acceleration to gain a better understanding of contemporary educational practices and how the COVID-19 pandemic is illustrative of this.

The regeneration of UV-written long period gratings (LPG) in boron-codoped germanosilicate “W” fibre is demonstrated and studied. They survive temperatures over 1000 °C. Compared with regenerated FBGs fabricated in the same type of fibre, the evolution curves of LPGs during regeneration and post-annealing reveal even more detail of glass relaxation. Piece-wise temperature dependence is observed, indicating the onset of a phase transition of glass in the core and inner cladding at ~500 °C and ~250 °C, and the melting of inner cladding between 860 °C and 900 °C. An asymmetric spectral response with increasing and decreasing annealing temperature points to the complex process dependent material system response. Resonant wavelength tuning by adjusting the dwell temperature at which regeneration is undertaken is demonstrated, showing a shorter resonant wavelength and shorter time for stabilisation with higher dwell temperatures. All the regenerated LPGs are nearly strain-insensitive and cannot be tuned by applying loads during annealing as done for regenerated FBGs.

A dual 830 and 980 nm pumping scheme is proposed aiming at broadening and flattening the spectral performance of bismuth/erbium codoped multicomponent fiber (BEDF). The spectral properties of distinct Bi active centers (BACs) associated with germanium (BAC-Ge), aluminium (BAC-Al), phosphorus (BAC-P) and silicon (BAC-Si) are characterized under single pumping of 830 and 980 nm, respectively. Based on the emission slope efficiencies of BAC-Al (∼1100 nm) and BAC-Si (∼1430 nm) under single pumping of 830 and 980 nm, the dual pumping scheme with the optimal pump power ratio of 25 (980 nm VS 830 nm) is determined to achieve flat, ultrabroadband luminescence spectra covering the wavelength range 950-1600 nm. The dual pumping scheme is further demonstrated on the on-off gain performance of BEDF. It is found under the pump power ratio of ∼8 (980 VS 830 nm), The gain spectrum has been flattened and broadened over 300 nm (1300-1600 nm) with an average gain coefficient of ∼1.5 dBm-1. The spectral coverage is approximately 1.5 and 3 times wider compared to single pumping of 830 and 980 nm pumping, respectively. The energy level diagrams of 830 and 980 nm are also constructed separately in view of the optical characteristic, which further clarifies the advantage for dual pumping. The proposed dual 830 and 980 nm pumping scheme with the multicomponent BEDF shows great potential in various broadband optical applications such as uniform ASE source, broadband amplifier and tuneable laser in NIR band.

Recently, we showed that femtosecond laser induced “nanogratings” consist of thin regions with a low refractive index (Δn = −0.15), due to the formation of nanoporous silica surrounded by regions with a positive index change. In this paper, we investigate a wide range of laser parameters to achieve very high retardance within a single layer; as much as 350 nm at λ = 546 nm but also to minimize the competing losses. We show that the total retardance depends on the number of layers present and can be accumulated in the direction of laser propagation to values higher than 1600 nm. This opens the door to using these nanostructures as refined building blocks for novel optical elements based on strong retardance.

The room temperature deposition of self-assembling silica nanoparticles onto D-shaped optical fibres (“D-fibre”), drawn from milled preforms fabricated by modified chemical vapour deposition (MCVD), is studied. Vertical dip-and-withdraw produces tapered layers, with one end thicker (surface coverage >0.85) than the other, whilst horizontal dip-and-withdraw produces much more uniform layers over the core region. The propagation of induced fracturing over the core region during drying is overcome using a simple protrusion of the inner cladding. Thick coatings are discernible through thin film interference colouring, but thinner coatings require scanning electron microscopy (SEM) imaging. Here, we show that fluorescence imaging, using Rhodamine B, in this example, can provide some qualitative and speedy assessment of coverage.

Percolation diffusion into long (11.5 cm) self-assembled, ordered mesoporous microfibres is studied using optical transmission and laser ablation inductive coupled mass spectrometry (LA-ICP-MS). Optical transmission based diffusion studies reveal rapid penetration ( 80 μm2∙s−1) of Rhodamine B with very little percolation of larger molecules such as zinc tetraphenylporphyrin (ZnTPP) observed under similar loading conditions. The failure of ZnTPP to enter the microfibre was confirmed, in higher resolution, using LA-ICP-MS. In the latter case, LA-ICP-MS was used to determine the diffusion of zinc acetate dihydrate, D~3 × 10−4 nm2∙s−1. The large differences between the molecules are accounted for by proposing ordered solvent and structure assisted accelerated diffusion of the Rhodamine B based on its hydrophilicity relative to the zinc compounds. The broader implications and applications for filtration, molecular sieves and a range of devices and uses are described.

Linewidth measurements of a distributed feedback (DFB) fibre laser are made using delayed self heterodyne interferometry (DHSI) with both Mach-Zehnder and Michelson interferometer configurations. Voigt fitting is used to extract and compare the Lorentzian and Gaussian linewidths and associated sources of noise. The respective measurements are wL (MZI) = (1.6 ± 0.2) kHz and wL (MI) = (1.4 ± 0.1) kHz. The Michelson with Faraday rotator mirrors gives a slightly narrower linewidth with significantly reduced error. This is explained by the unscrambling of polarisation drift using the Faraday rotator mirrors, confirmed by comparing with non-rotating standard gold coated fibre end mirrors.

The blue OLED emission from a mobile phone was characterised, revealing a sharp emission band centred at λ = 445 nm with a 3dB bandwidth Δλ ~ 20 nm. It was used to excite Rhodamine 123 doped within a “giant” mesostructured silica sphere during fabrication through evaporative self-assembly of silica nanoparticles. Fluorescence was able to be detected using a standard optical microscope fitted with a green transmission pass filter and cooled CCD and with 1 ms exposure time demonstrating the potential of mobile platforms as the basis for portable diagnostics in the field.

A regenerated optical fibre Bragg grating that survives temperature cycling up to 1,295°C is demonstrated. A model based on seeded crystallisation or amorphisation is proposed.

A new class of refractive index sensors using solid core photonic crystal fibres isdemonstrated. Coherent scattering at the cladding lattice is used to optically characterizematerials inserted into the fibre holes. The liquid to solid phase transition of water uponfreezing to ice 1h is characterized by determining the refractive index.

Between the late 60's and early 90's intensive exploitation of residual soil for civil construction took place in the municipality of Ubatuba, North Coast of São Paulo State. Tropical climatic conditions associated with a hilly landscape bordered by the Atlantic Ocean gave rise to thick (10-30m) weathering profiles derived from Precambrian granitic-gneissic rocks. Exploitation of large volumes of this material required only very simple technology, which on the other hand has caused highly adverse environmental impacts, such asdeforestation, soil erosion, land instability hazards, scenic eterioration, pollution and disturbance of local water flow regime. This paper deals with the devising of strategies thus identifying stakeholders and describing their roles both on the dereliction and reclamation processes related with residual soil exploitation. The evaluation approach focused on the analysis of the regulatory framework and its practical implications and issues in terms of licensing for mining operations, commercialization of construction materials, and the relations of such mining activities with regional and urban planning. A survey of stakeholderviewpoints was successfully achieved through a two-day workshop. The attendance included decision-makers, officials and representatives of governmental and regulatory bodies (Federal, State and Municipal), environmental research institutions, private miners (entrepreneurs) and consultants, public attorney, and NGOs. The outcomes have ndicated that State and local authorities properly managed to stop illegal exploitation of residual soil in the early 90´s. However no land reclamation was undertaken until present. One of the main problems would be related with the procedures for mining and environmental licensing that were considered to be too complex and long (usually involving up to seven decisional instances and 2,5 years in average). Other key issues and needs identified included: a)organization of a database in a Geographic Information System; b) formulation of a Regional Mining Directive Plan consonant with the other Management Plans; c) regulation of land ownership; d) regulatory framework able to reconcile development and preservation so that to prevent illegal mining; e) development of integrated models for reclamation taking comprehensive consideration to aggregate production, reduction of risks and land recovering.