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Abstract Visual speech recognition (VSR) is a challenging task that has received increasing interest during the last few decades. Current state of the art employs powerful end-to-end architectures based on deep learning which depend on large amounts of data and high computational resources for their estimation. We address the task of VSR for data scarcity scenarios with limited computational resources by using traditional approaches based on hidden Markov models. We present a novel learning strategy that employs information obtained from previous acoustic temporal alignments to improve the visual system performance. Furthermore, we studied multiple visual speech representations and how image resolution or frame rate affect its performance. All these experiments were conducted on the limited data VLRF corpus, a database which offers an audio-visual support to address continuous speech recognition in Spanish. The results show that our approach significantly outperforms the best results achieved on the task to date.

This contribution will analyze the significance and legacy of Next Generation EU (NGEU). It will start by providing a snapshot of the state of the EU's Economic and Monetary Union (EMU) before the pandemic struck in 2020. It will then map out NGEU's likely legacy, arguing that NGEU may change the way the EU raises and spends revenues in the future. The essay will finish by reflecting on how NGEU may change our interpretation of important elements of EMU and affect the ongoing debate about the future of fiscal integration within the EU.

This paper introduces a novel dynamic spectrum sharing (DSS) scheme designed for cell-free massive MIMO (CF-mMIMO) networks. The motivation behind this work arises from the urgent need to enhance spectrum utilization in modern wireless communication systems. Traditional spectrum allocation methods often struggle to meet the diverse spectrum demands of different wireless operators. The proposed approach addresses these challenges by enabling the spectrum provider (SP) to flexibly allocate and sell its spectrum resources, empowering wireless virtual operators to acquire bandwidth efficiently based on their specific needs. In our framework, each wireless operator is represented by a CF-mMIMO network, characterized by an average spectral efficiency metric that quantifies the potential value of additional spectrum acquisition. Leveraging a Stackelberg game formulation, our DSS policy achieves an equilibrium point that optimally allocates bandwidths to operators and determines corresponding prices. This approach not only enhances spectrum utilization but also fosters fair competition among operators. A key innovation of our work lies in the utilization of blockchain technology, where all spectrum transactions are managed through a smart contract. This ensures transparency, integrity, and auditability throughout the spectrum trading process. The novel protocol facilitates seamless information exchange, orchestrates the Stackelberg game dynamics, and delivers conclusive outcomes to both the SP and the CF-mMIMO operators.

Pesticide exposure is an important driver of bee declines. Laboratory toxicity tests provide baseline information on the potential effects of pesticides on bees, but current risk assessment schemes rely on one species, the highly social honey bee, Apis mellifera, and there is uncertainty regarding the extent to which this species is a suitable surrogate for other pollinators. For this reason, Osmia cornuta and Osmia bicornis have been proposed as model solitary bee species in the EU risk assessment scheme. The use of solitary bees in risk assessment requires the development of new methodologies adjusted to the biology of these species. For example, oral dosing methods used with honey bees cannot be readily applied to solitary bees due to differences in feeding behaviour and social interactions. In this study, we describe the “petal method”, a laboratory feeding method, and validate its use in acute and chronic exposure oral tests with Osmia spp. We conducted five experiments in which we compared the performance of several artificial flowers combining visual and olfactory cues against the petal method, or in which variations of the petal method were confronted. We then use the results of these experiments to optimize the feeding arenas and propose standardized methods for both acute and chronic exposure tests. The petal method provides high levels of feeding success, thus reducing the number of bees needed. It works with a wide variety of petal species and with both female and male Osmia spp., thus ensuring reproducibility across studies. To validate the use of the petal method in ecotoxicology tests, we assess the toxicity of a standard reference insecticide, dimethoate, in O. cornuta adults and determine LD50 values for this species. The petal method should facilitate the inclusion of solitary bees in risk assessment schemes therefore increasing the protection coverage of pesticide regulation.

In this paper, we present two proposals for multi-two-party contract signing with blockchain support. In the scenario in this paper, a customer wants to purchase products/services from multiple vendors with the requirement that she wants all or none of the products. Our proposals satisfy the security requirements for contract signing: fairness, timeliness, nonrepudiation, effectiveness and confidentiality. Furthermore, one of the two proposals requires the execution of blockchain functions only in the case of dishonest behaviour (bc-optimistic). The only previous solution found in the literature for the multi-two-party contract signing scenario requires the use of a trusted third party (TTP); however, the approach is highly inefficient, requiring the exchange of many messages. Our proposals are much more efficient than the TTP-based proposal, as our proposal reduces the number of exchanged messages required to complete multi-two-party contract signing. As the use of blockchain incurs a fee, we prove the technological and economic viability of our proposals on different blockchains.

Current pesticide risk assessment practices use the honey bee, Apis mellifera L., as a surrogate to characterize the likelihood of chemical exposure of a candidate pesticide for all bee species. Bees make up a diverse insect group that provides critical pollination services to both managed and wild ecosystems. Accordingly, they display a diversity of behaviors and vary greatly in their lifestyles and phenologies, such as their timing of emergence, degree of sociality, and foraging and nesting behaviors. Some of these factors may lead to disparate or variable routes of exposure when compared to honey bees. For those that possess life histories that are distinct from A. mellifera, further risk assessments may be warranted. In January 2017, 40 bee researchers, representative of regulatory agencies, academia, and agrochemical industries, gathered to discuss the current state of science on pesticide exposure to non-Apis bees and to determine how well honey bee exposure estimates, implemented by different regulatory agencies, may be protective for non-Apis bees. Workshop participants determined that although current risk assessment procedures for honey bees are largely conservative, several routes of exposure are unique to non-Apis bees and warranted further investigation. In this forum article, we discuss these key routes of exposure relevant to non-Apis bees and identify important research gaps that can help inform future bee risk assessment decisions.

In this article, we present the first proposal for contract signing based on blockchain that meets the requirements of fairness, hard-timeliness, and bc-optimism. The proposal, thanks to the use of blockchain, does not require the use of trusted third parties (TTPs), thus avoiding a point of failure and the problem of signatories having to agree on a TTP that is trusted by both. The presented protocol is fair because it is designed such that no honest signatory can be placed at a disadvantage. It meets the hard-timeliness requirement because both signatories can end the execution of the protocol at any time they wish. Finally, the proposal is bc-optimistic because blockchain functions are only executed in case of exception (and not in each execution of the protocol), with consequent savings when working with public blockchains. No previous proposal simultaneously met these three requirements. In addition to the above, this article clarifies the concept of timeliness, which previously has been defined in a confusing way (starting with the authors who used the term for the first time). We conducted a security review that allowed us to verify that our proposal meets the desired requirements. Furthermore, we provide the specifications of a smart contract designed for the Ethereum blockchain family and verified the economic feasibility of the proposal, ensuring it can be aligned with the financial requirements of different scenarios.

Promotional schemes, such as promotional points and coupons, are highly effective marketing tools. Through these schemes, merchants can obtain customer loyalty or attract new customers, and customers can obtain benefits when purchasing goods or services. Therefore, the use of promotional schemes is considered to be a win-win strategy. Promotional points are becoming an increasingly popular way of providing customers with discounts or gifts to incentivise the purchase of some products. However, some security issues should be addressed: forgery, double-spending, privacy, etc. Blockchain is gaining popularity in academic research and business applications, as it has the potential to change business models in numerous sectors of the economy. The characteristics of blockchain (security, immutability, efficiency, etc.) can help to provide secure solutions for blockchain-based applications in the marketing field. In this paper, we propose a multimerchant, blockchain-based promotional point scheme that allows points to be transferred between customers and preserves customers’ privacy.

Abstract Purpose The primary aim of the present study is to report the late acute hematogenous (LAH) prosthetic joint infection (PJI) cure rate following Total knee arthroplasty (TKA) treated by means of debridement, antibiotics, and implant retention (DAIR) in a long‐term follow‐up. The secondary purpose is to report the functional outcomes at that follow‐up and to compare them with a non‐infected group. Material and Methods This study cohort consists of 2,498 TKA performed from September 2005 to April 2010 that had a minimum follow‐up of 10 years. The diagnosis of PJI and classification into LAH was done in accordance with the Zimmerli criteria. The primary outcome was the failure rate, defined as death before the end of antibiotic treatment, a further surgical intervention for treatment of infection, life‐long antibiotic suppressive treatment or chronic infection. The Knee Society Score (KSS) was used to evaluate clinical outcomes. Results Ten patients were diagnosed with acute hematogenous PJI during the study period (0.4%). All of them were managed with DAIR, which was performed by a knee surgeon and/or PJI surgeon. The failure rate was 0% at the 8.5‐year (SD, 2.4) follow‐up mark. The KSS score was 82.1 vs. 84.1 (p n.s.) at final follow‐up. Conclusion Although the literature suggests that TKA DAIR for LAH periprosthetic joint infection is associated with high rates of failure, the results presented here suggest a high cure rate with good functional outcomes. Level of evidence Level II, prospective cohort study.

Abstract Background The aim of the present study was to evaluate the incidence of unsuspected PJI when prosthetic revisions are thoroughly evaluated by PJI dedicated orthopedic surgeon before surgery. The hypothesis is that the incidence of unsuspected PJI is reduced by applying this protocol. Methods This is a historical cohort study carried out in one university hospital. The prosthetic revision assessment was carried out in January 2019. From that date on, all patients that were programmed for hip or knee revision (either by an orthopedic surgeon specialized or not in septic revisions) were scheduled for a preoperative visit with the same orthopedic surgeon specialized in septic revisions. The diagnostic algorithm applied was based on the Pro-Implant Foundation diagnostic criteria. Prior to the revision assessment, the indication for joint aspiration was done at the surgeons’ discretion (non-specialized in septic revisions) and the preoperative identification of PJI was also done by a hip or knee surgeon (not specialized in septic surgery). Results Based on the PIF criteria, there were 15 infections among the revisions in group 1 and 18 PJI in group 2 (p > 0.05). The most interesting finding was that there were 7 patients with unsuspected positive cultures in group 1. That represents 11% of all revisions. No patient in group 2 was found with unsuspected positive cultures (p

Visual speech recognition (VSR) is a challenging task that aims to interpret speech based solely on lip movements. However, although remarkable results have recently been reached in the field, this task remains an open research problem due to different challenges, such as visual ambiguities, the intra-personal variability among speakers, and the complex modeling of silence. Nonetheless, these challenges can be alleviated when the task is approached from a speaker-dependent perspective. Our work focuses on the adaptation of end-to-end VSR systems to a specific speaker. Hence, we propose two different adaptation methods based on the conventional fine-tuning technique, the so-called Adapters. We conduct a comparative study in terms of performance while considering different deployment aspects such as training time and storage cost. Results on the Spanish LIP-RTVE database show that both methods are able to obtain recognition rates comparable to the state of the art, even when only a limited amount of training data is available. Although it incurs a deterioration in performance, the Adapters-based method presents a more scalable and efficient solution, significantly reducing the training time and storage cost by up to 80%.

One of the most severe complications of primary total knee arthroplasty (TKA) is prosthetic joint infection. Currently, the use of antibiotic-loaded cement for the prevention of infection is still controversial. The aim of the present study was to evaluate if the use of antibiotic-loaded cement reduces the infection rate in primary TKA in long-term follow-up (more than 5 years average follow-up). This study is the follow-up extension of a prospective randomized study, with 2,893 cemented TKA performed between 2005 and 2010 at our institution. There were 2 different cohorts depending on which bone cement was used: without antibiotics (control group) or those loaded with erythromycin and colistin (study group). All patients received the same systemic prophylactic antibiotics. The patients were followed for a minimum of twelve months. The diagnosis of prosthetic joint infection was done according to Zimmerli criteria. In 1,452 patients, the prosthetic components were fixed using bone cement without antibiotics, whereas in 1,441 patients, bone cement was loaded with erythromycin and colistin. Both groups were comparable in terms of all the possible risk factors studied. We found a total of 53 deep infections, with a mean rate of 1.8%. There were no differences between the groups as to whether bone cement with or without antibiotics had been used (P =.58). The average duration of follow-up was 8.7 years. In terms of prosthetic revision due to aseptic loosening, there were no differences between groups (P =.32), with 33 revision arthroplasties in the control group and 37 in the study group. Moreover, we analyzed the erythromycin resistance rate, with no differences between both groups (P =.6). The use of erythromycin and colistin-loaded bone cement in TKA did not lead to a decrease in the rate of infection in long-term follow-up, a finding that suggests that its use would not be indicated in the general population. [ABSTRACT FROM AUTHOR]

In this article, we present the first solution for multi-party certified email that achieves fairness and confidentiality without the intervention of a TTP but with blockchain support when problems arise. Our solution preserves the confidentiality of the mail exchanged between the sender and the recipients even when the blockchain is involved. We provide a proof of concept implementation based on Ethereum smart contracts that shows it is feasible from a practical point of view. Because the functions of a smart contract are only executed on the blockchain in the case of conflict, costs are minimised compared to solutions that execute the functions on the blockchain in all cases (on-chain solutions). Moreover, the solution can be integrated into the existing email infrastructure.

El objeto de este artículo es contribuir a la aportación de una información detallada acerca de la batería de San Francisco de Paula, fortificación construida en el lado sureste de la ciudad de San Juan de Puerto Rico, para evitar posibles desembarcos enemigos en este sector. Son muy pocos los autores que mencionan esta obra y se desconoce el momento exacto de su construcción, aunque varias fuentes gráficas y documentales localizadas en el Archivo General Militar de Madrid, el Archivo Histórico Nacional y el Archivo General de Puerto Rico, analizadas para este estudio, permiten constatar que fue levantada a finales del siglo XVIII por el ingeniero militar, de origen español, Juan Francisco Mestre.

Background: Total knee arthroplasty (TKA) has become the gold standard for the definitive treatment of knee osteoarthritis. One crucial aspect in the implantation of a TKA is the precise orientation of the femoral and tibial components. The main purpose of the present study is to assess, in patients undergoing total knee replacement, whether the difference between the planned angulation in the distal femoral cut and the angulation obtained in the postoperative radiological control is low enough to consider the conventional bone-cutting guides reliable. Methods: A retrospective study was designed with a consecutive series of patients who had undergone primary total knee arthroplasty using conventional instrumentation over one year. The authors analysed the main variable (bone cuts) while considering different variables (age, gender, surgeon, prosthesis, laterality, constraint, body mass index and alignment) to identify different patient patterns that justify the results in the main variable. Descriptive variables were analysed using the Mann–Whitney U and Kruskal–Wallis tests. Additionally, the correlation between continuous variables was explored in accordance with the Spearman correlation. Results: A total of 340 patients with a mean age of 75 ± 9.16 years were finally included in the present study. The mean absolute error of the main variable for the femoral coronal bone cut was 1.89° (SD 1.53). For the tibial coronal bone cut, it was 1.31° (SD 2.54). These values correspond to what remains after subtracting the radiological angulation obtained in the postoperative period from the planned intraoperative angulation of the distal femoral cut. No associations were observed between the main variable (the angulation of the proximal tibial cut and distal femoral cut) and the rest of variables for either the femur or tibia. Conclusion: A discrepancy between the planned angulation and the final radiological measure on the coronal plane of the femur and tibia using conventional cutting guides has been demonstrated. The degree of deviation is low enough that it probably does not affect clinical outcomes. Therefore, the use of conventional cutting guides will continue to be an appropriate tool to perform bone cuts in knee replacement surgery.

El objeto de este artículo es analizar el primer sistema de alumbrado marítimo construido por la Corona española en varios puntos estratégicos del litoral de Puerto Rico e islas adyacentes a mediados del siglo XIX, con el fin de asegurar y desarrollar el comercio y la economía insular, garantizar mayor seguridad a la navegación, reforzar la defensa de los principales puertos comerciales y evitar posibles desembarcos enemigos. El estudio está basado en el análisis de varias fuentes gráficas y documentales custodiadas en el Archivo Histórico Nacional, desconocidas hasta la fecha, las cuales permiten examinar de manera detallada la construcción de cada uno de los faros. Además de contribuir a la aportación de información inédita, acerca de los ingenieros de obras públicas que trabajaron en la isla durante esta centuria, cuya labor ha pasado desapercibida para historiadores y expertos en Arquitectura.