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Three volcanic plumes were detected during the Tajogaite volcano eruptive activity (Canary Islands, Spain, September–December 2021) over the Iberian Peninsula. The spatiotemporal evolution of these events is characterised by combining passive satellite remote sensing and ground-based lidar and sun-photometer systems. The inversion algorithm GRASP is used with a suite of ground-based remote sensing instruments such as lidar/ceilometer and sun-photometer from eight sites at different locations throughout the Iberian Peninsula. Satellite observations showed that the volcanic ash plumes remained nearby the Canary Islands covering a mean area of 120 ± 202 km2 during the whole period of eruptive activity and that sulphur dioxide plumes reached the Iberian Peninsula. Remote sensing observations showed that the three events were mainly composed of sulphates, which were transported from the volcano into the free troposphere. The high backscatter-related Ångström exponents for wavelengths 532–1064 nm (1.17 ± 0.20 to 1.40 ± 0.24) and low particle depolarization ratios (0.08 ± 0.02 to 0.09 ± 0.02), measured by the multi-wavelength Raman lidar, hinted at the presence of spherical small particles. The layer aerosol optical depth at 532 nm (AODL532) obtained from lidar measurements contributed between 49% and 82% to the AERONET total column AOD at 532 nm in event II (11–13 October). According to the GRASP retrievals, the layer aerosol optical depth at 440 nm (AODL440) was higher in all sites during event II with values between 0.097 (Badajoz) and 0.233 (Guadiana-UGR) and lower in event III (19–21 October) varying between 0.003 (Granada) and 0.026 (Évora). Compared with the GRASP retrievals of total column AOD at 440 nm, the AODL440 had contributions between 21% and 52% during event II. In the event I (25–28 September), the mean volume concentrations (VC) varied between 5 ± 4 µm3cm-3 (El-Arenosillo/Huelva) and 17 ± 10 µm3cm-3 (Guadiana-UGR), while in event II this variation was fro, Évora team funded by national funds through FCT - Fundação para a Ciência e Tecnologia, I.P., in the framework of the ICT project with the references UIDB/04683/2020 and UIDP/04683/2020 and by TOMAQAPA (PTDC/CTAMET/29678/2017). The authors acknowledge the GRASP-ACE (Grant agreement ID: 778349), ACTRIS-IMP (Grant agreement ID:871115), ATMO-ACCESS (Grant Agreement ID: 101008004), PROBE (COST Action number: CA18235), HARMONIA (COST Action number: CA21119), EUMETNET through the E-PROFILE program and REALISTIC (Grant agreement ID:101086690) projects. The authors acknowledge the support through ACTRIS-2 under grant agreement no.654109. This work was partially supported by the Spanish national projects PID2019-103886RB-I00/AEI/10.13039/501100011033, INTEGRATYON3 (PID2020-117825GB-C21 and PID2020-117825GB-C22), ELPIS (PID2020-120015RB-I00), CLARIN (CGL2016-81092-R), ePOLAAR (RTI2018-097864-B-I00), CAMELIA (PID2019-104205GB-C21/AEI/10.13039/501100011033) and ACTRIS-España (CGL2017-90884REDT), by University of Granada Plan Propio through Singular Laboratory (LS2022-1) program, by the Andalusia Autonomous Government projects AEROPRE (P18-RT-3820) and ADAPNE (P20_00136), by the UGR-FEDER projects DEM3TRIOS (A-RNM-430-UGR20) and MOGATRACO (A-RNM-524-UGR20) and partially by the Scientific Units of Excellence Program (grant no. UCE-PP2017-02), and by the R+D+i grant RTI 2018-097332-B-C22 funded by MCIN/AEI/ 10.13039/501100011033/ and “ERDF A Way of Doing Europe”. M.-Á. López-Cayuela and C.V. Carvajal-Pérez are supported by the INTA predoctoral contract program., Peer Reviewed, Postprint (published version)

Ecuador harbors an astounding number of ecosystems and species. However, anthropogenic land-use changes are the primary drivers of biodiversity loss in major taxonomic groups, especially insects. Among them, the Scarabaeinae subfamily containing dung beetles, is an excellent taxon for studying alpha, beta, and functional diversity, as well as modified landscapes allowing us to infer whether agriculture, human settlements, and the environment variables, affect their structure and distribution. Furthermore, recent approaches on dung beetle´s knowledge, focus mostly on taxonomy, therefore there is a growing interest on ecological analysis that will help us understand and solve hypothesis and questions about their behavior, species loss, and distribution. To understand the main drivers of dung beetle’s distribution, functionality and behavior, we conducted various analysis utilizing a museum database from the National Institute of Biodiversity, Ecuador (INABIO) of over 5000 dung beetle specimens collected throughout the country, addressing the following questions: i) How does tribe distribution vary across climatic and elevational gradients? ii) How does functional and taxonomic beta diversity vary across spatial scales? iii) How different agriculture systems promote biodiversity and iv) How human settlements affect their functional biodiversity? To address these questions, we performed generalized linear models to estimate Ecuador’s distributions based on climate to explore potential predictor variables, along with taxonomic and functional beta diversity across scales. In addition to this, we used functional and diversity analyses, beta diversity and NMDS, along with GLM’s to determine how agricultural practices and human settlements affect their diversity in Ecuador. We have found that their distribution is mainly influenced by biogeography and climate as their main ecological and environmental factors, Kichua settlements in the Amazon do not alter their functional di, Ecuador alberga una asombrosa cantidad de ecosistemas y especies. Sin embargo, los cambios antropogénicos y el cambio en el uso de la tierra son los principales impulsores de la pérdida de biodiversidad en muchos grupos taxonómicos; entre ellos, los Scarabaeinae o escarabajos estercoleros, un excelente taxón para estudiar la diversidad alfa, beta y funcional de paisajes modificados permitiéndonos inferir si la agricultura, los asentamientos humanos y las variables ambientales afectan su estructura y distribución. Además, los enfoques recientes sobre el conocimiento estos escarabajos se centran en taxonomía, por lo que existe un interés creciente en el análisis ecológico que ayuda a comprender, resolver hipótesis y preguntas sobre su comportamiento, pérdida de especies y distribución. Para comprender los principales impulsores de la distribución, la funcionalidad y el comportamiento de los escarabajos coprófagos, realizamos varios análisis utilizando la base de datos del museo del Instituto Nacional de Biodiversidad de Ecuador (INABIO) con más de 5000 especímenes de escarabajos coprófagos recolectados en todo el país, abordando las siguientes preguntas de variación y distribución de escarabajos en gradientes climáticos y altitudinales, variación de la diversidad beta funcional y taxonómica a través de las escalas espaciales, ¿Cómo los diferentes sistemas agrícolas promueven la biodiversidad y ¿Cómo los asentamientos humanos afectan su biodiversidad funcional? Para abordarlas, realizamos modelos lineales generalizados estimando las distribuciones de Ecuador en función del clima, junto con diversidad beta funcional y taxonómica en todas las escalas. Además de esto, utilizamos análisis funcional y de diversidad alfa y beta, con NMDS, para determinar cómo las prácticas agrícolas y los asentamientos humanos afectan su diversidad en el Ecuador. Encontramos que la distribución está influenciada principalmente por la biogeografía y el clima como sus principales factores ecol

Remote attestation is a powerful mechanism that allows a verifier to know if the hardware of an IoT (Internet-of-Thing) device (acting as a prover) has been counterfeited or tampered with and if its firmware has been altered. Remote attestation is based on collecting and reporting measurements in a trusted way, and should be lightweight for resource-constrained IoT devices. This work proposes to include a low-cost Root of Trust for Measuring and Reporting (RoTMR) in the prover, based on the combination of a Physically Unclonable Function (PUF) and an Attestation Read-Only Memory (A-ROM), and to use hash-based digital signatures in the attestation protocol. The proposed RoTMR is addressed to IoT devices based on a microcontroller that executes some application code (the measurable object) located in an external non-volatile memory accessible by an attacker. The secret keys required by the digital signatures are not stored but reconstructed using the PUF. The A-ROM contains the attestation instructions and ensures that its contents cannot be altered and that its instructions are executed sequentially without modification. The use of hash-based digital signatures makes the solution quantum-resistant and very robust because its security relies solely on the unidirectionality of a hash function. The proposed attestation protocol takes advantage of the fact that One-Time Signature (OTS) generation and Many-Time Signature (MTS) verification are very well suited for low-end devices, and the MTS scheme is suitable for the verifier application context. The proposal was validated experimentally with the ESP32 microcontroller, which is widely employed in IoT devices, by using its SRAM as PUF and implementing WOTS+, which is a type of Winternitz One-Time Signature scheme (WOTS), the One-Time Signature of Smart Digital Signatures scheme (SDS-OTS), and the MTS schemes constructed with them. The OTS schemes require smaller codes and thus smaller A-ROM than MTS and ECDSA (Elliptic C

Homomorphic encryption is a powerful mechanism that allows sensitive data, such as biometric data, to be compared in a protected way, revealing only the comparison result when the private key is known. This is very useful for non-device-centric authentication architectures with clients that provide protected data and external servers that authenticate them. While many reported solutions do not follow standards and are not resistant to quantum computer attacks, this work proposes a secure biometric authentication scheme that applies homomorphic encryption based on the Classic McEliece public-key encryption algorithm, which is a round 4 candidate of the NIST post-quantum standardization process. The scheme applies specific steps to transform the features extracted from biometric samples. Its use is proposed in a non-device-centric biometric authentication architecture that ensures user privacy. Irreversibility, revocability and unlinkability are satisfied and the scheme is robust to stolen-device, False-Acceptance Rate (FAR) and similarity-based attacks as well as to honest-but-curious servers. In addition to the security achieved by the McEliece system, which remains stable over 40 years of attacks, the proposal allows for very reduced storage and communication overheads as well as low computational cost. A practical implementation of a non-device-centric facial authentication system is illustrated based on the generation and comparison of protected FaceNet embeddings. Experimental results with public databases show that the proposed scheme improves the accuracy and the False-Acceptance Rate of the unprotected scheme, maintaining the False-Rejection Rate, allows real-time execution in clients and servers for Classic McEliece security parameter sets of 128 and 256 bits (mceliece348864 and mceliece6688128, respectively), and reduces storage requirements in more than 90.5% compared to the most reduced-size homomorphic encryption-based schemes with post-quantum security