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Historic Building Information Modelling (HBIM) plays a pivotal role in heritage conservation endeavours, offering a robust framework for digitally documenting existing structures and supporting conservation practices. However, HBIM's efficacy hinges upon the implementation of case-specific approaches to address the requirements and resources of each individual asset and context. This paper defines a flexible and generalisable workflow that encompasses various aspects (i.e., documentation, surveying, vulnerability assessment) to support risk-informed decision making in heritage management tailored to the peculiar conservation needs of the structure. This methodology includes an initial investigation covering historical data collection, metric and condition surveys and non-destructive testing. The second stage includes Finite Element Method (FEM) modelling and structural analysis. All data generated and processed are managed in a multi-purpose HBIM model. The methodology is tested on a relevant case study, namely, the church of Santa Ana in Seville, chosen for its historical significance, intricacy and susceptibility to seismic action. The defined level of detail of the HBIM model is sufficient to inform the structural analysis, being balanced by a more accurate representation of the alterations, through linked orthophotos and a comprehensive list of alphanumerical parameters. This ensures an adequate level of information, optimising the trade-off between model complexity, investigation time requirements, computational burden and reliability in the decision-making process. Field testing and FEM analysis provide valuable insight into the main sources of vulnerability in the building, including the connection between the tower and nave and the slenderness of the columns. [ABSTRACT FROM AUTHOR]

Multiwall carbon nanotubes (CNTs) decorated with cobalt oxide (CoO x ) nanoparticles (NPs) are prepared in various synthesis conditions to investigate their capability as oxygen reduction reaction (ORR) catalysts for fuel cells in alkaline media. The synthesis conditions include the use of protecting, reducing or complexing agents and heat treatment. Higher ORR activity is possible for smaller size of Co NPs catalysts due to the enlarged interfaces between Co species and CNTs. The addition of polyvinylpyrrolidone (PVP) as protecting agent and NaBH 4 during the preparation procedure is necessary for obtaining the highest activity since it favors the formation of lower oxidation states for Co species and the incorporation of N groups which improve ORR activity. CNTs loaded with only 1 wt.% of Co NPs prepared by a facile method using PVP, NaBH 4 and subsequent heat treatment at 500 °C under N 2 atmosphere, demonstrates both similar catalytic activity and stability than Pt/Vulcan (20 wt.% Pt on Vulcan). The synergic chemical coupling effects between CNTs and CoO x NPs and the presence of carbon material with pyridinic N and quaternary N groups formed from the protecting agent decomposition, seem to be the main factors responsible for the remarkable electrocatalytic activity. [ABSTRACT FROM AUTHOR]

Simple, cost-effective, and reproducible devices have been prepared for the detection of H 2 at room temperature. Pd, Cu and bimetallic Cu-Pd nanoparticles (prepared by the reduction-by-solvent method) have been loaded on a MWCNT deposit avoiding the use of surfactants or complicated techniques. The devices based on pure Pd nanoparticles have shown a high H 2 sensitivity in the studied H 2 concentration range with low response and recovery times. However, the addition of Cu in the metallic nanoparticles does not result in a considerable improvement. Furthermore, the Pd and Cu-Pd/MWCNTs-based sensors have kept part of their H 2 sensitivity when they have been tested in an O 2 -depleted atmospheres, which is an altogether new finding compared to Pd-based systems. Through these experiments it has been possible to conclude how the main H 2 detection mechanism is the electron transfer from the nanoparticles (when the PdH x is formed) to the carbon nanotubes. [ABSTRACT FROM AUTHOR]

In the propylene epoxidation reaction with Fe-SiO 2 catalysts the presence of iron oxide particles has a detrimental effect due to the total combustion of propylene on these iron species. Thus, the complete elimination of the iron oxide particles is presented as a preliminary strategy in order to increase the selectivity towards propylene oxide in iron-based catalysts. In this sense, a simple post-treatment of the catalysts with alkali or alkaline-earth elements (such as K or Ca, respectively) has proven effective in the total elimination of these iron oxide particles. Furthermore, the addition of K and Ca has modified the physico-chemical properties of the catalysts, decreasing their superficial acidity and (for higher K or Ca loadings) masking/blocking the active sites responsible for the catalytic reaction. With all this, it is shown that K has a higher efficiency removing the iron oxide particles compared with Ca (for the same molar ratios) and that a higher amount of K (compared to Fe) is required for the complete elimination of the iron oxide particles. A considerable propylene oxide selectivity enhancement (up to 65%) has been obtained for the K-promoted Fe 0.005 SiO 2 and Fe 0.01 SiO 2 catalysts using O 2 as sole oxidant. [ABSTRACT FROM AUTHOR]

Many catalytic applications use conventional heating to increase the temperature to allow the desired reaction. A novel methodology is presented for the preparation of magnetic zeolite-based catalysts, allowing more efficient radiofrequency heating. These nanoreactors are tested in the isomerisation of citronellal with successful results and without any apparent deactivation. [ABSTRACT FROM AUTHOR]

Palladium nanoparticles (Pd NPs) were synthesized by the reduction-by-solvent method using polyvinylpirrolidone (PVP) as capping agent. The nonstatic interaction between PVP and the metallic surface may change the properties of the NPs due to the different possible interactions, through either the O or N atoms of the PVP. In order to analyze these effects and their repercussions in their catalytic performance, Pd NPs with various PVP/Pd molar ratios (1, 10, and 20) were prepared, deposited on silica, and tested in the formic acid decomposition reaction. The catalytic tests were conducted using catalysts prepared by loading NPs with three different time lapses between their purification and their deposition on the silica support (1 day, 1 month, and 6 months). CO adsorption, FTIR spectroscopy, XPS, and TEM characterization were used to determine the accessibility of the Pd NPs surface sites, the electronic state of Pd, and the average NPs size, respectively. The H2 production from the formic acid decomposition reaction has a strong dependence on the Pd surface features, which in turn are related to the NPs aging time due to the progressive removal of the PVP. [ABSTRACT FROM AUTHOR]

Background: Studies in adults show that with a 3 or 4 cm distance between active and reference electrodes, maximum amplitude and latency values of sensitive nerve action potentials are obtained. The purpose of this study was to identify, in healthy children, the interelectrode distances at which the amplitude and peak latency do not differ significantly from those obtained with the intereletrode distance at which the maximum values are obtained. Methods: Four reference electrodes were placed at 1, 2, 3 and 4 cm distance from the active electrode. The electrode signal was recorded simultaneously with a physical jumper between the four channels. A sample of 66 median nerves was analyzed in children aged 5 to 9 years. Amplitude and latency maximum values were obtained with an interelectrode distance of 4 cm. Values obtained with 4 cm were compared against those obtained with 1, 2 and 3 cm interelectrode distances. Results: Amplitude values did not show significant difference with 3 and 4 cm interelectrode distances (p = 0.216). With regard to latency, the values did not indicate significant difference with the 4 and 3 cm interelectrode distances (p = 0.266). Conclusions: The amplitude increase resulting from interelectrode distance augmentation is not influenced by the peripheral nerve growth process in children. The optimal distance for the record of the nerve potential actions was similar to that seen in adults. [ABSTRACT FROM AUTHOR]

Abstract: Pd and bimetallic Ni50Pd50 nanoparticles protected by polyvinylpyrrolidone (PVP) have been synthesized by the reduction-by-solvent method and deposited on single wall carbon nanotubes (SWCNTs) to be tested as H2 sensors. The SWCNTs were deposited by drop casting from different suspensions. The Pd nanoparticles-based sensors show a very reproducible performance with good sensitivity and very low response times (few seconds) for different H2 concentrations, ranging from 0.2% to 5% vol. H2 in air at atmospheric pressure. The influence of the metal nanoparticle composition, the quality of SWCNTs suspension and the metal loading have been studied, observing that all these parameters play an important role in the H2 sensor performance. Evidence for water formation during the H2 detection on Pd nanoparticles has been found, and its repercussion on the behaviour of the assembled sensors is discussed. The sensor preparation procedure detailed in this work has proven to be simple and reproducible to prepare cost-effective and highly efficient H2 sensors that perform very well under real application conditions. [Copyright &y& Elsevier]

Background: Treatment-resistant major depression (MDD) and obsessive–compulsive disorder (OCD) remain a major cause of suffering and disability. These disorders may be treated with functional neurosurgery that almost always is bilateral but some patients might benefit from unilateral procedures. Methods: We performed a unilateral right anterior capsulotomy (AC) in a 45-year-old right-handed woman with MDD and comorbid OCD. This unilateral procedure was based on the results of neuropsychological testing and an 18-Fluorodeoxyglucose positron emission tomography (FDG-PET) that revealed right hemisphere deficits in this patient. Results: Following surgery, Hamilton Depression scale (HAM-D) decreased 57% at 1 and 2 years and 54% at 3 years and Yale-Brown Obsessive-Compulsive Scale (Y-BOCS) decreased 58% at 1 year, 77% at 2 years, and 96% at 3 years. There was a slight decrement of verbal memory and phonemic fluency after the procedure that could also be related to changes in medication. Right basal ganglia abnormalities revealed by FDG-PET remained unchanged 16 months postoperatively. Conclusions: Overall this unilateral right AC was effective for the treatment of this woman's disorders with minimal adverse side effects. [ABSTRACT FROM AUTHOR]

Growth parameters and production of the population of D. obesulus at the exposed sandy beach of Sarapampa (100 km south of Lima) were estimated. Monthly samplings were carried out during a year (October 2005-August 2006) in 6 stations distributed throughout the beach. Length- frequency distributions were elaborated and the growth parameters of the Von Bertalanffy growth equation (VBGE) determined by ELEFAN I. Total mortality rate (Z) was estimated by the length- based catch curve method and production of somatic and shell components were estimated by the mass specific growth rate method. Growth parameters were estimated as K= 0.991 and L∞= 33.70 mm and total mortality as Z= 3.28. Mean biomass was calculated using the relation length-shell and free wet mass (SFWM = 0.0003 L3.-61 ) as 54.10 g SFWM.m -2. The average production of this species was calculated in terms of ash free dry weight in 3.76 g AFDW.m-2 .year-1. Individuals ranging from 22 to 23 mm contributed most to the total production (10.3%). Mean annual turnover rate (P/ B̅) was 1.20. Growth and production of this species is compared with other species of the same genus. [ABSTRACT FROM AUTHOR]

This study analyzes and compares the growth and survival of juvenile Argopecten purpuratus cultivated in suspended and bottom systems in Casma, Ancash-Peru. From July 29th to October 21th, 2006 an experiment was installed using pearl nets and yards with individuals of 10mm² (0.067g of soft tissue) at densities of 816, 2450, and 4080 indiv/m . Every two weeks individuals were measured (mm, shell height) and weighted (g, total and tissue weight) and dead scallops counted. Additionally information on production costs was recorded in order to compare profits in both systems. At the end of the experiment height and weight were higher in suspended than in bottom system and showed an inverse relation with density. Growth rates in height and weight in suspended system ranged from 0.07 to 0.43 mm/day and from 0.009 and 0.100 g/day and in bottom system varied between 0.11 and 0.26 mm/day and between 0.007 and 0.045 g/day, respectively. Survival was higher in suspended (96.8%) than in bottom systems (84.8%). The ANOVA showed a significant effect of density and culture system on growth and survival of juvenile scallops (P<0.01). The cost-benefit analysis demonstrated that scallop culture in bottom systems is more profitable than in suspended systems. Maximum profit is reached in bottom systems at a density of 4080 ind/m² and at 816 ind/m² in suspended systems. The feasibility of the adoption of bottom systems for culture of juveniles by enterprises and fisherman is discussed. [ABSTRACT FROM AUTHOR]

The main purpose of this paper is to estimate 2D and 3D transformation parameters. All the group transformations are represented in terms of their Lie algebra elements. The Lie algebra approach assures to follow the shortest path or geodesic in the involved Lie group. For the estimation of the Lie algebra parameters, we take advantage of the theory of system identification. Two experiments are presented to show the potential of the method. First, we carry out the estimation of the affine or projective parameters related to the transformation involved in monocular region tracking. Second, we develop a monocular method to estimate 3D motion of an object in the visual space. In the latter, the six parameters of the rigid motion are estimated based on measurements of the six parameters of the affine transformation in the image. [Copyright &y& Elsevier]

In this paper, an embedded design for implementing a real-time photovoltaic (PV) system emulator with user-defined environmental conditions is proposed. The design implemented on a Sitara Cortex 9 ARM processor allows the evaluation of PV cells in a low-cost, portable and affordable system. This embedded PV emulation system uses an LCD screen to establish a human-system interface (HSI), and it contains an extensible database of commercial PV cells with their manufacturer’s datasheet parameters. Based on the accurate two-diode model, the proposed design allows the generation of high precision I – V , P – V characteristic curves with the embedded ARM, which represents an affordable and simple solution. Experimental results demonstrate the accuracy of the real-time embedded system for different solar cells and environmental conditions. [ABSTRACT FROM AUTHOR]

Novel hierarchical SiO 2 monolithic microreactors loaded with either Pd or Pt nanoparticles have been prepared in fused silica capillaries and tested in the Preferential Oxidation of CO (PrOx) reaction. Pd and Pt nanoparticles were prepared by the reduction by solvent method and the support used was a mesoporous SiO 2 monolith prepared by a well-established sol–gel methodology. Comparison of the activity with an equivalent powder catalyst indicated that the microreactors show an enhanced catalytic behavior (both in terms of CO conversion and selectivity) due to the superior mass and heat transfer processes that take place inside the microchannel. TOF values at low CO conversions have been found to be ∼2.5 times higher in the microreactors than in the powder catalyst and the residence time seems to have a noticeable influence over the selectivity of the catalysts designed for this reaction. The Pd and Pt flexible microreactors developed in this work have proven to be effective for the CO oxidation reaction both in the presence and absence of H 2 , standing out as a very interesting and suitable option for the development of CO purification systems of small dimensions for portable and on-board applications. [ABSTRACT FROM AUTHOR]

Agave tequilana Weber var. azul fibers (ATF) are widely used as a reinforcement material despite their polarity makes them incompatible with hydrophobic matrices. Consequently, ATF are commonly modified employing different chemical processes (e.g., mercerization and coupling agents) to change their surface characteristics to improve the interface between the fibers and the polymeric matrix. Nevertheless, these treatments could damage the fibers during the process, negatively affecting their natural properties. The use of nanotechnology to repair this natural material could help to restore its intrinsic properties and give it new ones as antibacterial activity. In this work, chemically treated ATF were used as templates for the biosynthesis of silver nanoparticles (AgNPs) using a natural extract obtained from Agave tequilana Weber var. azul leaves (ATL) as reducing agent. Scanning and transmission electron microscopy images as well as dynamic light scattering results indicate that stable nanometric particles were successfully synthesized on all fibers. X-ray photoelectron spectroscopy and X-ray diffraction results confirm the composition of the nanoparticles. Tensile tests indicate that AgNPs improved the mechanical properties of fibers previously mercerized and treated with maleic anhydride grafted polyethylene as coupling agent. Additionally, an antibacterial effect against S. enterica was conferred to ATF due to the presence of AgNPs. [ABSTRACT FROM AUTHOR]

Electric arc furnaces (EAFs) contribute to almost one third of the global steel production. Arc furnaces use a large amount of electrical energy to process scrap or reduced iron and are relevant to study because small improvements in their efficiency account for significant energy savings. Optimal controllers need to be designed and proposed to enhance both process performance and energy consumption. Due to the random and chaotic nature of the electric arcs, neural networks and other soft computing techniques have been used for modeling EAFs. This study proposes a methodology for modeling EAFs that considers the time varying arc length as a relevant input parameter to the arc furnace model. Based on actual voltages and current measurements taken from an arc furnace, it was possible to estimate an arc length suitable for modeling the arc furnace using neural networks. The obtained results show that the model reproduces not only the stable arc conditions but also the unstable arc conditions, which are difficult to identify in a real heat process. The presented model can be applied for the development and testing of control systems to improve furnace energy efficiency and productivity. [ABSTRACT FROM AUTHOR]

This paper focuses on the synthesis of nanocomposite materials, TiO/SAPO-34, using the sol-gel method, which involves preparing a mixture between as-synthesized or calcined SAPO-34 zeolite and TiO gel under hydrothermal crystallization and then calcining it at 400 °C for the formation of the TiO anatase phase. The structural and textural features of the obtained materials were determined by various physico-chemical techniques such as thermogravimetric analysis, X-ray diffraction, scanning electronic microscopy, nitrogen sorption at 77 K, energy dispersive X-ray analysis and ultraviolet-visible spectrometry. The DRX results showed that calcination at 400 °C of the mixture between the calcined SAPO-34 and TiO gel led to the collapse of the original framework of zeolite, but formed the anatase TiO in a nano-spherical morphology; however, the use of as-synthesized SAPO-34 supports provides a mixture phase between SAPO-34 and TiO anatase after calcination. The photocatalytic properties of the SAPO-34/TiO and TiO-type materials were tested for the removal of methylene blue (MB) dye. The MB degradation proved to increase as a function of contact time, catalyst mass and the initial concentration of MB. [ABSTRACT FROM AUTHOR]

Background: Treatment-resistant major depression (MDD) and obsessive-compulsive disorder (OCD) remain a major cause of suffering and disability. These disorders may be treated with functional neurosurgery that almost always is bilateral but some patients might benefit from unilateral procedures. Methods: We performed a unilateral right anterior capsulotomy (AC) in a 45-year-old right-handed woman with MDD and comorbid OCD. This unilateral procedure was based on the results of neuropsychological testing and an 18-Fluorodeoxyglucose positron emission tomography (FDG-PET) that revealed right hemisphere deficits in this patient. Results: Following surgery, Hamilton Depression scale (HAM-D) decreased 57% at 1 and 2 years and 54% at 3 years and Yale-Brown Obsessive-Compulsive Scale (Y-BOCS) decreased 58% at 1 year, 77% at 2 years, and 96% at 3 years. There was a slight decrement of verbal memory and phonemic fluency after the procedure that could also be related to changes in medication. Right basal ganglia abnormalities revealed by FDG-PET remained unchanged 16 months postoperatively. Conclusions: Overall this unilateral right AC was effective for the treatment of this woman's disorders with minimal adverse side effects. [ABSTRACT FROM AUTHOR]

Background. Elastosonography is a tool which, since its introduction in 1991, is applied to conventional ultrasound to analyze and provide morphological data different from that obtained in mode B. It is used to assess the elasticity of different components of mammary tissue showing the properties of lesions by evaluating their elasticity when subjected to external compression. Because elasticity is lower in rigid than in soft lesions, this data could prove useful as an auxiliary tool in diagnosing breast cancer: it is a known principle that malignant lesions are less elastic, and therefore present greater resistance to displacement than benign lesions. purpose. Evaluate the diagnostic usefulness of elastosonography as a complementary tool to conventional ultrasound in the study of probably benign, American College of Radiology (ACR) category BI-RADS 3 mammary lesions, by relating its results with cyto/histological diagnosis as standard reference. Material and methods. Comparative, transverse, retrospective, retrolective study. Thirty-eight patients with lesions assessed by elastosonography and their correlation with the cyto/histological result were analyzed by kappa coefficient of diagnostic correlation. Positive and negative predictive values were established for the lesions studied, corresponding to category BI-RADS 3. results. Of 38 patients, 35 (92.2%) presented lesions in benign category in elastosonography and the cyto/histological result was also benign; 3 patients (7.8%) presented benign lesions in elastosonography but their cyto/histological result was malignant. The morphological characteristics of the lesions were: 31 nodular lesions (81.57%) and 7 cystic lesions (18.43 %), of which 5 corresponded to complex cysts. analysis and discussion. Elastosonography showed diagnostic accuracy of 92.1%, similar to that found by Tardivon et al. (87.5%). Elastosonography proved more useful to classify nodular images of small size and posterior localization as cystic than conventional ultrasound which assesses only the morphological appearance of the lesion without considering other properties of the tissues. Conclusion. In our work elastosonography proved to be a useful diagnostic complement for managing BI-RADS 3 lesions. Negative elastosonographic results led to a change of the initial classification of lesions while positive elastosonographic results were decisive to change the expectation to direct intervention to obtain a histopathological correlation. This new echographic tool is promising because i t adds certainty to the diagnosis and is especially useful in lesions cataloged in mode B as probably benign. [ABSTRACT FROM AUTHOR]

The emergence of modern technologies, such as Wireless Sensor Networks (WSNs), the Internet-of-Things (IoT), and Machine-to-Machine (M2M) communications, involves the use of batteries, which pose a serious environmental risk, with billions of batteries disposed of every year. However, the combination of sensors and wireless communication devices is extremely power-hungry. Energy Harvesting (EH) is fundamental in enabling the use of low-power electronic devices that derive their energy from external sources, such as Microbial Fuel Cells (MFC), solar power, thermal and kinetic energy, among others. Plant Microbial Fuel Cell (PMFC) is a prominent clean energy source and a step towards the development of self-powered systems in indoor and outdoor environments. One of the main challenges with PMFCs is the dynamic power supply, dynamic charging rates and low-energy supply. In this paper, a PMFC-based energy harvester system is proposed for the implementation of autonomous self-powered sensor nodes with IoT and cloud-based service communication protocols. The PMFC design is specifically adapted with the proposed EH circuit for the implementation of IoT-WSN based applications. The PMFC-EH system has a maximum power point at 0.71 V, a current density of 5 mA cm − 2 , and a power density of 3.5 mW cm − 2 with a single plant. Considering a sensor node with a current consumption of 0.35 mA, the PMFC-EH green energy system allows a power autonomy for real-time data processing of IoT-based low-power WSN systems. [ABSTRACT FROM AUTHOR]