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Sn-silica catalyzes cheese whey to lactic acid in a fluidized bed reactor
Get PDFWorldwide, the dairy industry produces 200 million tons per year of whey. Among the most abundant components of cheese whey is lactose, a low-priced raw material for nutraceuticals, animal feed, and high value products such as lactic acid (LA)., a specialty chemical platform in the pharmaceutical, cosmetic, and in the food industry, and is the precursor to polylactic acid, a biodegradable polymer. Here, we propose a fluidized bed process that atomizes an aqueous lactose solution directly into a catalytic bed operating at 325∘C to produce LA. We synthesized silica supported Sn catalysts by varying the metal loading (from 0 to 0.1 g g−1 of Sn) and analyzed its physicochemical properties. This research highlights the critical role of Sn as an active site to hydrolyse/isomerize/retro-aldol/dehydrate/crack lactose to lactic acid in a gas phase environment. All catalysts achieved complete conversion. SiO2 impregnated with 0.1 g g−1 Sn catalyst achieved the maximum lactic acid yield of 23 % at 2 h of the reaction. Lactic acid yield declined thereafter due to coke blocking the active catalytic sites. XPS, Raman and CHN analysis highlighted changes in carbon distribution and evidence of coke accumulation in the spent catalyst. This article brings new findings related to significant challenges related to the continuous operation of a fluidized bed reactor in the conversion of lactose and strategies to mitigate agglomeration and coke formation.Funding for open access charge: Universidad de Málaga / CBU
In vivo assessment of ankle stability during dynamic exercises: scoping review
No full textBackground: The ankle joint plays a key role in stabilizing the lower limb during interaction
with ground reaction forces. Instability can result in pain, weakness, and impaired
movement. Although assessing ankle stability is important, few studies examine existing
in vivo methodologies for dynamic load assessment, limiting effective injury management.
Objective: To identify in vivo techniques using objective measurement tools for assessing
ankle stability during dynamic exercise. Methods: A scoping review was performed based
on PRISMA-ScR criteria. Five databases—PubMed, PEDro, Embase, SPORTDiscus, and
CDSR—were searched from inception to September 2024. Results: Out of 1678 records,
32 studies met the inclusion criteria. A total of 1142 subjects were included: 293 females
(25.6%), 819 males (71.7%), and 30 unspecified (2.62%). Six categories of dynamic exercise
were identified: analytical, functional, balance, stair climbing, running, and walking. The
techniques used included 3D motion capture, force and pressure platforms, dynamometry,
electromyography, accelerometers, pressure and speed sensors, instrumented treadmills,
and inertial measurement units. Conclusions: The 3D motion capture systems (240 Hz)
and the force platforms (1000 Hz) were most frequently used in functional tasks and
walking. Combining these with multisegmented foot models appears optimal, though
tool selection depends on study goals. This review enhances our understanding of ankle
stability assessment
CRDT-based knowledge synchronisation in an Internet of Robotics Things ecosystem for Ambient Assisted Living
No full textIntegrating IoT and assistive robots in the design of Ambient Assisted Living (AAL) frameworks has proven to be a useful solution for monitoring and assisting elderly people at home. As a way to manage the information captured and assess the person’s condition, respond to emergencies, promote physical or cognitive exercises, etc., these systems can also integrate a Virtual Caregiver (VC). Given the diversity of technologies deployed in such an AAL framework, deciding how to manage knowledge appropriately can be complex. This paper proposes to organise the AAL framework as a distributed system, i.e., as a collection of autonomous software agents that provide users with a single coherent response. In this distributed system, agents are deployed locally and handle replicas of the knowledge model. The problem of merging these replicas into a consistent representation, therefore arises.The
-CRDT (Conflict-free Replicated Data Type) synchronisation mechanism is employed to ensure the eventual consistency with low communication overhead. To manage the dynamics of the AAL ecosystem, the
-CRDT is combined with the publish/subscribe interaction protocol. In this way, the performance of the IoT, the robot and the VC, through the functionalities that depend on them, is efficiently adapted to changes in the context. To demonstrate the validity of the proposal, two use cases have been designed in which a collaborative response from the system is required. The first one deals with a possible fall of the user at home, while the second one deals with the problem of helping the person move small objects around the flat. The measured values of latency or consistency in the data show that the proposal works satisfactorily.Funding for open access charge: Universidad de Málaga / CBU
Real-Time FTM-based Victim Positioning System Using Heterogeneous Robots in Remote and Outdoor Scenarios.
Get PDFAccurate victim localization in Remote, Outdoor, Unstructured, and Disaster (ROUD) scenarios remains a significant challenge due to limited infrastructure, complex terrains, and time constraints inherent in Search and Rescue (SAR) operations. This article introduces an innovative real-time positioning system that leverages Fine Time Measurement (FTM), a feature of the IEEE 802.11mc amendment, to detect WiFi-enabled devices typically carried by potential victims. The system integrates a Hybrid Wireless Sensor Network (H-WSN) composed of static and mobile anchors mounted on Uncrewed Ground and Aerial Vehicles (UGVs and UAVs), within a Robot Operating System (ROS)-based architecture. A centralized Feedback Information System (FIS) processes real-time RTT data from the field, executes a multilateration algorithm, and provides live geolocation updates to SAR coordinators. The system was validated during a large-scale SAR drill, successfully locating two types of victims—a semi-hidden surface victim and a buried victim—within a 2000m2 area in under 7 minutes, without any filtering or post-processing. The maximum positioning error was 22.87m for the buried victim and 17.14m for the surface one. The complete system, including source code, dataset, and a containerized environment, is openly available to support reproducibility and further research, highlighting the potential of robotic and wireless technologies to enhance disaster response through accurate, real-time localization in complex environments
Fuzzy time series analysis: Expanding the scope with fuzzy numbers
Get PDFThis article delves into the process of fuzzifying time series, which entails converting a conventional time series into a time-indexed sequence of fuzzy numbers. The focus lies on the well-established practice of fuzzifying time series when a predefined degree of uncertainty is known, employing fuzzy numbers to quantify volatility or vagueness. To address practical challenges associated with volatility or vagueness quantification, we introduce the concept of informed time series. An algorithm is proposed to derive fuzzy time series, and findings include the examination of structural breaks within the realm of fuzzy time series. Additionally, this article underscores the significance of employing topological tools in the analysis of fuzzy time series, accentuating the role of these tools in extracting insights and unraveling intricate relationships within the data.Funding for open access charge: Universidad de Málaga / CBU
Secure Multi-Party Computation: Constructions and Applications in Blockchain
Get PDFProtection of data in use is a new paradigm that aims to provide data owners with mechanisms to ensure that their data is not exposed, even when it is part of a computation. Within this paradigm, Privacy Enhancing Technologies (PETs) in general, and Secure Multi-Party Computation (MPC) in particular, offer interesting possibilities for security, mainly by relying on cryptographic techniques. Among the wide range of applications that can benefit from MPC, we identify one of great interest that lacks privacy by default: blockchain. Blockchain technologies require data to be publicly available in order to guarantee the verifiability and correctness of their results, but this implies an obstacle for many use cases to be adopted in the decentralized environment.
This thesis is devoted to the study of MPC from a practical point of view, and mainly to the relations that exist between MPC and blockchain. This work is carried out at different levels, from the more general to the more specific. More specifically, we provide an analysis and discussion of different MPC protocols and their peculiarities when used in real systems. We also provide specific solutions to achieve privacy-preserving applications in the blockchain ecosystem by relying on MPC. We approach this not from a specific application, but from a general computational approach, where MPC serves as a confidentiality layer that can be invoked from smart contracts. On the other hand, at the cryptographic level, we provide a new solution to achieve an efficient and dynamic delivery of secret shared data to outsourced MPC committees. This allows data owners to benefit from sending a single ciphertext that can be shared publicly, and also from selecting the specific committee to share the data after it has been encrypted and stored.This new construction, namely Oblivious Sharing Re-Encryption (OSRE), benefits some scenarios, such as those in which IoT devices send periodic data, or those in blockchain that rely on MPC for confidential computations. Finally, we also provide three applications where PETs in general and MPC in particular offer privacy and usability improvements: Private Set Intersection (PSI) computations in consortium blockchains, a privacy-preserving use of location data for a crowd counting application, and a decentralized mixer service in Bitcoin with reversible unlinkability that achieves accountability and compliance while ensuring that payments remain private
FICHA Nº 6. Personal laboral al servicio de las Administraciones Públicas.
No full textENLACE DEL REPOSITORIO DE LA UNIVERSIDAD DE SEVILLA DONDE LA OBRA SE ENCUENTRA EN ABIERTO
https://hdl.handle.net/11441/166924FICHA Nº 6. Personal laboral al servicio de las Administraciones PúblicasUniversidad de Sevill
Effect of different custom-made foot orthotics on foot joint stiffness in individuals with structural hallux limitus: A quasi-experimental study
Get PDFBackground: Normal dorsiflexion of the first metatarsophalangeal joint during dynamic activities is critical for
effective propulsion. Therapeutic foot orthotics may address the pathomechanical loading and joint kinematics
issues faced by this population. This study aims to evaluate the effect of two different types of Custom-made foot
orthosis compared to shod condition on the stiffness of the rearfoot, midfoot, and 1st metatarsophalangeal joint
during walking in patients with Structural Hallux Limitus.
Methods: This quasi-experimental study used a repeated-measures design with a single cohort. 24 participants
with structural hallux limitus were sampled. Two custom-made Foot Orthotics – a cut-out and an anterior
forefoot stabiliser element – were compared under three conditions using minimalist SAGURO neoprene shoes:
shod, shod with cut-out custom-made foot orthosis, and shod with anterior forefoot stabiliser element foot
orthosis. Kinematic data were captured using a modified Bruening model. We examined the variable stiffness
(quantified in Nm/Kg/rad).
Findings: Significant differences were found in dynamic stiffness only between Anterior forefoot stabiliser
element custom-made foot orthosis, and the patient shod during the propulsion phase at the 1st Meta-
tarsophalangeal joint (R2 = 0,07 p = 0.027) and a difference of 0,86 Nm/kg/rad. No significant differences were
observed for dynamic stiffness in any other phase of the stance period across all conditions.
Interpretation: The Anterior forefoot stabiliser element, in particular, significantly increases the stiffness of the 1st
Metatarsophalangeal joint compared to walking shod.Funding for open access charge is provided by Universidad de Malaga/CBU
