Abstract
This study investigates the antifragility of organizations, especially in strategic sectors highly exposed to disruptive events. Based on a qualitative approach with case studies in the wine and textile sectors in Portugal, the findings indicate that financial and market strength, as resilience capabilities, operate interdependently and are reinforced by digital maturity and supply chain integration. Companies with financial robustness and strong market intelligence tend to be more agile in strategically investing and reallocating resources during crises. The research adopts an expanded definition of antifragility, which incorporates resilience, innovation, and strategic reconfiguration in the face of disruptions. It concludes that organizational antifragility results from the articulation of financial resources, market intelligence, and digital collaboration, offering a sustainable competitive advantage in the face of uncertainty. The study contributes to theoretical debates and provides practical recommendations for managers and policymakers.

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[No abstract available]

Abstract
The present study investigates the impact of a virtual Vernier effect in the fundamental state and first harmonic to enhance the sensitivity of a strain sensor. A fibre loop mirror (FLM) combined with an internal elliptical cladding (IEC) fibre section was used as the sensor, while a virtual reference spectrum derived from theoretical equations enabled the Vernier effect. For the individual sensor, a sensitivity of 15.39 ± 0.03 pmµe?¹ and a free spectral range (FSR) of 4.22 ± 0.01 nm are obtained. For the virtual Vernier effect, a detuning of 0.15 m is used in both states, resulting in an FSR of 30.2 ± 0.1 nm. A sensitivity of 109.8 ± 0.7 pmµe?¹ is achieved for the fundamental state, associated with a figure of merit (FoM) of 1.01 ± 0.03, and a sensitivity of 230 ± 2 pmµe?¹ for the first harmonic, associated with a figure of merit (FoM) of 2.1 ± 0.1. This work demonstrates the feasibility of implementing the virtual Vernier effect, not only enabling Vernier effect amplification but also reducing implementation complexity and increasing system robustness under harsh conditions.

Abstract
The decoupling of temperature and refractive index measurements was achieved by exploiting the properties of the asymmetric spectrum generated by Fano resonance, resulting from the interference between the Bragg reflection of the grating and the Fresnel reflection at the fiber tip. This spectral asymmetry enabled the implementation of a combined wavelength-based and intensity-based interrogation scheme. By separating the influence of each parameter in the spectral response, it was possible to measure the refractive index independently, without interference from temperature variations. A refractive index sensor with a minimum detectable change of delta = 1.2 & times; 10(-4) RIU was demonstrated. In addition to introducing a novel structure that leverages Fano resonance, the sensor was also applied as an evaporation rate sensor. The results demonstrate its potential for a wide range of applications, serving as a foundation for the development of future optical sensing technologies.

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Abstract
This study experimentally investigates the impact of EDFA pump power on the State of Polarization (SOP) in optical fiber systems at 1550 nm, with particular relevance for distributed sensing applications. Using a tunable laser and polarimeter, three power levels were tested:-18 dBm,-20 dBm, and-23 dBm. Results show that polarization stability is strongly affected by power: while-18 dBm and-20 dBm provided repeatable SOP and phase behavior,-23 dBm caused significant phase shifts and Stokes parameter drift. Furthermore, for EDFA output powers greater than 0 dBm, the polarization state exhibits a strong dependence on optical power. Despite these effects, Polarization Dependent Gain (PDG) remained low (~ 0.46 dB), confirming the EDFA meets commercial specifications. The study highlights a trade-off where lower input powers, though avoiding saturation, can worsen polarization instability in short fiber systems, which is critical for optical communication and distributed sensing design.