Estimation of specific cutting energy in an S235 alloy for multi-directional ultrasonic vibration-assisted machining using the Finite Element Method

The objective of this work is to analyze the influence of the vibration-assisted turning process on the machinability of S235 carbon steel. During the experiments using this vibrational machining process, the vibrational amplitude and frequency of the cutting tool were adjusted to drive the tool tip in an elliptical or linear motion in the feed direction. Furthermore, a finite element analysis was deployed to investigate the mechanical response for different vibration-assisted cutting conditions. The results show how the specific cutting energy and the material’s machinability behave when using different operational cutting parameters, such as vibration frequency and tool tip motion in the x-axis, y-axis, and elliptical (x-y plane) motion. Then, the specific cutting energy and material’s machinability are compared with a conventional turning process, which helps to validate the finite element method (FEM) for the vibration-assisted process. As a result of the operating parameters used, the vibration-assisted machining process leads to a machinability improvement of up to 18% in S235 carbon steel. In particular, higher vibration frequencies were shown to increase the material’s machinability due to the specific cutting energy decrease. Therefore, the finite element method can be used to predict the vibration-assisted cutting and the specific cutting energy, based on predefined cutting parameters.Peer ReviewedPostprint (published version

3D-printed alginate-hydroxyapatite aerogel scaffolds for bone tissue engineering

3D-printing technology allows the automated and reproducible manufacturing of functional structures for tissue engineering with customized geometries and compositions by depositing materials layer-by-layer with high precision. For these purposes, the production of bioactive gel-based 3D-scaffolds made of biocompatible materials with well-defined internal structure comprising a dual (mesoporous and macroporous) and highly interconnected porosity is essential. In this work, aerogel scaffolds for bone regeneration purposes were obtained by an innovative strategy that combines the 3D-printing of alginate-hydroxyapatite (HA) hydrogels and the supercritical CO2 drying of the gels. BET and SEM analyses were performed to assess the textural parameters of the obtained aerogel scaffolds and the dimensional accuracy to the original computer-aided design (CAD) design was also evaluated. The biological characterization of the aerogel scaffolds was also carried out regarding cell viability, adhesion and migration capacity. The obtained alginate-HA aerogel scaffolds were highly porous, biocompatible, with high fidelity to the CAD-pattern and also allowed the attachment and proliferation of mesenchymal stem cells (MSCs). An enhancement of the fibroblast migration toward the damaged area was observed in the presence of the aerogel formulations tested, which is positive in terms of bone regenerationThis work was supported by Xunta de Galicia [ED431C 2020/17], MICINN [PID2020-120010RB-I00], Agencia Estatal de Investigación [AEI] and FEDER funds. Work carried out in the framework of the COST Action CA18125 “Advanced Engineering and Research of aeroGels for Environment and Life Sciences” (AERoGELS) and funded by the European Commission. A.I.-M. acknowledges to Xunta de Galicia for her predoctoral research fellowship [ED481A- 2020/104]. A. Alonso is commended for his technical contribution to this workS

Special Issue: Biopolymers in Drug Delivery and Regenerative Medicine

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Anomalías de la anatomía coronaria. A propósito de un caso

A pesar de los numerosos avances tecnológicos, las anomalías anatómicas coronarias siguen siendo una patología infradiagnosticada que, aunque infrecuente, es potencialmente letal en determinados subgrupos. El objetivo de esta revisión es resaltar aquellos hallazgos que nos deben hacer sospecharlas, así como desarrollar brevemente el abordaje diagnóstico y las posibles opciones terapéuticas disponibles actualmente

Wild boar battues reduce crop damages in a protected area

Agricultural damages caused by wild boar Sus scrofa have given farmers a negative impression of protected areas and their management. To mitigate those damages and the social conflicts that they create, hunting battues involving experienced local hunters were used as a lethal population control method in a protected Iberian wetland. In the Ebro Sotos and Galachos Nature Reserve, Spain, between 1994 and 2011, 259 wild boars were culled during 476 battues. On average, battues involved six hunters and ten dogs, and culling efficiency (number of animals killed per animals seen during battues) was 39 %. The number of battues per year and the area of crop damages caused by wild boar were significantly negatively correlated, demonstrating battue efficiency to decrease damages. Moreover, intermittent population control through culling led to a substantial increase in the wild boar population, with an increase in crop damages. This underlines the importance of constant control. The numbers of hunters and dogs and the number of wild boar seen during battues were strongly correlated. To minimize the conflicts between farmers and the management of protected areas, we suggest that the inexpensive, volunteer-based population control program could be enhanced by incorporating stalking and mobile electric fences

Mesenchymal stem cells secretome : The cornerstone of cell-free regenerative medicine

Mesenchymal stem cells (MSCs) are the most frequently used stem cells in clinical trials due to their easy isolation from various adult tissues, their ability of homing to injury sites and their potential to differentiate into multiple cell types. However, the realization that the beneficial effect of MSCs relies mainly on their paracrine action, rather than on their engraftment in the recipient tissue and subsequent differentiation, has opened the way to cell-free therapeutic strategies in regenerative medicine. All the soluble factors and vesicles secreted by MSCs are commonly known as secretome. MSCs secretome has a key role in cell-to-cell communication and has been proven to be an active mediator of immune-modulation and regeneration both in vitro and in vivo. Moreover, the use of secretome has key advantages over cell-based therapies, such as a lower immunogenicity and easy production, handling and storage. Importantly, MSCs can be modulated to alter their secretome composition to better suit specific therapeutic goals, thus, opening a large number of possibilities. Altogether these advantages now place MSCs secretome at the center of an important number of investigations in different clinical contexts, enabling rapid scientific progress in this field.Supported by Spanish Ministerio de Economía y competitividad, No. RTI2018-097324; Predoctoral program in Biomedicine from the University of Cantabria and the Instituto de Investigación Valdecilla (IDIVAL), No. PREVAL 19/02 and PREVAL 20/01

Software Process Simulation Modeling: Systematic literature review

Changes and continuous progress in logistics and productive systems make the realization of improvements in decision making necessary. Simulation is a good support tool for this type of decisions because it allows reproducing processes virtually to study their behavior, to analyze the impact of possible changes or to compare different design alternatives without the high cost of scale experiments. Although process simulation is usually focused on industrial processes, over the last two decades, new proposals have emerged to bring simulation techniques into software engineering. This paper describes a Systematic Literature Review (SLR) which returned 8070 papers (published from 2013 to 2019) by a systematic search in 4 digital libraries. After conducting this SLR, 36 Software Process Simulation Modeling (SPSM) works were selected as primary studies and were documented following a specific characterization scheme. This scheme allows characterizing each proposal according to the paradigm used and its technology base as well as its future line of work. Our purpose is to identify trends and directions for future research on SPSM after identifying and studying which proposals in this topic have been defined and the relationships and dependencies between these proposals in the last five years. After finishing this review, it is possible to conclude that SPSM continues to be a topic that is very much addressed by the scientific community, but each contribution has been proposed with particular goals. This review also concludes that Agent-Based Simulation and System Dynamics paradigm is increasing and decreasing, respectively, its trend among SPSM proposals in the last five years. Regarding Discrete-Event Simulation paradigm, it seems that it is strengthening its position among research community in recent years to design new approaches.Ministerio de Economía y Competitividad TIN2016-76956-C3-2-

Every Fish Counts: Challenging Length–Weight Relationship Bias in Discards

Bycatch is a significant issue in global fisheries and understanding the length–weight relationships (LWR) of fish species can provide valuable insights for stock assessment and management efforts. In this study, we estimated the LWR of 74 fish species in trawl fleet discards from the Gulf of Cadiz, including 24 species for which LWR data had not been previously reported in this region. LWR was calculated from the formula W = aLb where parameter a is the intercept of the equation, related to body shape, and parameter b is the slope, which indicates the type of growth of the species. A total of 20,007 individuals from 40 families were measured and weighed. The most abundant species were Engraulis encrasicolus, Trachurus trachurus, Serranus hepatus, Sardina pilchardus, Capros aper, and Diplodus bellottii, and the Sparidae family was the most represented with ten species. The parameter b, which represents the type of growth, ranged from 2.1607 to 3.7040. A positive allometric growth trend was observed in 64% of the species. The inclusion of individuals with a low sample size proved useful, particularly for first reports in a new study area. However, caution should be taken when using these data, as the estimates of the length–weight relationship for these species may be less precise. Further studies with larger sample sizes are needed to confirm the results and improve the accuracy of the estimates. Overall, our findings contribute to the understanding of the LWR of fish species in the Gulf of Cadiz, informing future research and management efforts in the region.This research has been carried out within the framework of the ECOFISH project: ecoinnovative strategies for sustainable fishing in the Gulf of Cadiz SPA. This initiative has been supported by the Biodiversity Foundation, the Ministry for Ecological Transition and Demographic Challenge, through the Pleamar Program, co-financed by the European Maritime and Fisheries Fund (EMFF) [grant number: 2019-016/PV/PLEAMAR18/PT; 2020-013/PV/PLEAMAR19/PT; 2020- 055/PV/PLEAMAR20/PT; 2021/PV/PLEAMAR20-21/PT; 2021-060/PV/PLEAMAR21/PT]

Predicting response to transdiagnostic iCBT for emotional disorders from patient and therapist involvement

Background Transdiagnostic iCBT has been shown to be effective for the treatment of emotional disorders. Less is known about the optimal level of therapist and patient involvement in these interventions. Specific characteristics of Internet-delivered interventions include treatment adherence (e.g., amount of review of the materials) and guidance (e.g., amount of therapist support). Exploring the importance of these elements in treatment outcome may help to maximize the efficiency of Internet-delivered psychological interventions. Aim In this study, we aimed to analyze the relationship between patient and therapist involvement (i.e., platform usage and amount of therapist guidance) in a sample of patients with emotional disorders who received transdiagnostic iCBT in Spanish public specialized mental healthcare services. Method This is a secondary analysis of a randomized controlled trial. The sample included 63 patients who completed transdiagnostic iCBT for emotional disorders. Platform usage metrics included number of logins into the platform and number of times the participants reviewed the modules. Therapist guidance was measured as the number of support phone calls with a therapist and their total duration (minutes). Logistic regressions and ROC analyses were performed to explore the predictive value of platform usage and therapist guidance in symptom reduction. Clinical outcomes included depressive and anxiety symptoms assessed at baseline and post-intervention. The bivariate relationship between the platform usage and therapist guidance variables was also explored. Results Overall, platform usage and therapist guidance were not associated with symptom improvement. However, the patient and therapist involvement parameters were intercorrelated. Specifically, the number of calls and their duration were associated with a greater number of logins (r = 0.61; p < .001) and more frequent reviews of the modules (0.46 ≤ r ≤ 0.60; p < .001). Higher baseline depression and anxiety were, respectively, associated with greater improvements in depression (r = −0.37, p = .003) and anxiety after treatment completion (r = −0.48, p < .001). Discussion The results suggest that there is no reliable cut-off point for platform usage and therapist guidance in predicting optimal symptom reduction. However, significant associations were found between platform usage and guidance variables that warrant additional research. More research on this topic is necessary to further clarify the role of these and other platform usage and guidance variables in Internet-delivered iCBT outcomes