Road freight transport is one of the sectors with the highest greenhouse gas emissions and fuel consumption in the logistics industry. In recent years, due to the increase in carbon dioxide ...emissions, several companies have considered reducing them in their daily logistics operations by means of better routing management. Green vehicle routing problems (GVRPs) constitute a growing problem direction within the interplay of vehicle routing problems and environmental sustainability that aims to provide effective routes while considering environmental concerns. These NP-hard problems are one of the most studied ones in green logistics, and due to their difficulty, there are many different heuristic and hybrid techniques to solve them under the need of having high-quality solutions within reasonable computational time. Given the role and importance of these methods, this review aims at providing a comprehensive overview of them while reviewing their defining strategies and components. In addition, we analyze characteristics and problem components related to how emissions are being considered. Lastly, we map and analyze the benchmarks proposed so far for the different GVRP variants considering emissions.
Prostate Cancer and the Mevalonate Pathway Guerrero-Ochoa, Patricia; Rodríguez-Zapater, Sergio; Anel, Alberto ...
International journal of molecular sciences,
02/2024, Letnik:
25, Številka:
4
Journal Article
Recenzirano
Odprti dostop
Antineoplastic therapies for prostate cancer (PCa) have traditionally centered around the androgen receptor (AR) pathway, which has demonstrated a significant role in oncogenesis. Nevertheless, it is ...becoming progressively apparent that therapeutic strategies must diversify their focus due to the emergence of resistance mechanisms that the tumor employs when subjected to monomolecular treatments. This review illustrates how the dysregulation of the lipid metabolic pathway constitutes a survival strategy adopted by tumors to evade eradication efforts. Integrating this aspect into oncological management could prove valuable in combating PCa.
Endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) is the technique of choice in the study of mediastinal and hilar lesions; however, it can be affected by the insufficiency ...of intact biopsy samples, which might decrease its diagnostic yield for certain conditions, thus requiring re-biopsies or additional diagnostic procedures such as mediastinoscopy when the probability of malignancy remains high. Our objectives were to 1) attempt to reproduce this technique in the same conditions that we performed EBUS-TBNA,
in the bronchoscopy suite and under moderate sedation; 2) describe the method used for its execution; 3) determine its feasibility by accessing different lymph node stations applying our method; and 4) analyse the diagnostic yield and its complications.
This was a prospective study of 50 patients who underwent EBUS-TBNA and EBUS-guided transbronchial mediastinal cryobiopsy (TMC) in a single procedure using a 22-G TBNA needle and a 1.1-mm cryoprobe subsequently between January and August 2022. Patients with mediastinal lesions >1 cm were recruited, and EBUS-TBNA and TMC were performed in the same lymph node station.
The diagnostic yield was 82% and 96% for TBNA and TMC, respectively. Diagnostic yields were similar for sarcoidosis, while cryobiopsy was more sensitive than TBNA in lymphomas and metastatic lymph nodes. As for complications, there was no pneumothorax and in no case was there significant bleeding. There were no complications during the procedure or in the follow-up of these patients.
TMC following our method is a minimally invasive, rapid and safe technique that can be performed in a bronchoscopy suite under moderate sedation, with a higher diagnostic yield than EBUS-TBNA, especially in cases of lymphoproliferative disorders and metastatic lymph nodes or when more biopsy sample is needed for molecular determinations.
Traditionally, reinforced concrete (RC) piles for earth retaining systems have been designed using symmetrical reinforcement. The non-symmetric or asymmetric RC pile is a recently patented structural ...element. Savings of up to 50% of longitudinal reinforcing steel can be obtained using non-symmetrically reinforced piles in comparison with traditional symmetrical ones. In this work, the calculation of the short-term deflection of cracked RC piles using the concept of effective moment of inertia is investigated. Five specimens with both symmetric and asymmetric reinforcements were tested in four-point bending tests. In addition, a numerical finite element analysis of symmetric and non-symmetric circular RC members was also carried out to enlarge the available database. The widely used expressions of effective moments of inertia proposed by Branson and Bischoff (originally conceived for rectangular sections) were adapted to fit experimental and numerical results. Both symmetrically and asymmetrically reinforced concrete elements were studied. Keywords: Bischoff equation; Branson equation; circular reinforced concrete sections; effective moment of inertia; reinforced concrete (RC); wall pile.
Octahedron family: The double-expanded octahedron tensegrity Fernández-Ruiz, Manuel Alejandro; Hernández-Montes, Enrique; Carbonell-Márquez, Juan Francisco ...
International journal of solids and structures,
06/2019, Letnik:
165
Journal Article
Recenzirano
Odprti dostop
The octahedron family of tensegrity structures is presented in this research. The octahedron and the expanded octahedron (well-known tensegrities in the literature) are the first and second ...components of the family. A new tensegrity is presented: the double-expanded octahedron. This new tensegrity form was obtained following the connectivity pattern of the octahedron family presented in this work. The values of the force densities or force:length ratios that satisfy the minimum required rank deficiency of the force density matrix were computed analytically. Two types of solutions are obtained: full and folded forms. Results show that each lower member of the octahedron family is a folded form of a superior member of this family. Several examples are shown.
Display omitted
This article is about the current agricultural scenario, where large‐scale production causes large amounts of food to be transported to various points of consumption, causing substantial emissions of ...so‐called greenhouse gases and increasing the carbon footprint. Land use optimization and land parcel allocation are essential areas of agriculture research that currently represent relevant challenges and are classified as combinatorial optimization problems. In this context, the Selection and Allocation of Land Parcels Problem (SA‐LPP) is proposed; its goal is to optimize the selection and allocation of land parcels with rectangular shapes in small areas available for food production. We propose a reformulation of the SA‐LPP as a variant of the two‐dimensional orthogonal packing problem (2OPP), called Group‐2OPP. This problem was solved through a Mixed‐Integer Linear Programming (MILP) model, but due to the model complexity, we also propose a Greedy Randomized Adaptive Search Procedure metaheuristic approach. Some sensitivity analyses were performed as well to evaluate the impact of parameters on the solutions. Computational results show that the proposed metaheuristic outperforms the MILP model in terms of solution quality and computational times.
The generation of energy from renewable sources is a fundamental aspect for the sustainable development of society, and several energy sources such as solar, biomass, biogas, and wind must be used to ...the maximum to meet existing needs. In Chile, there are villages that are off-grid. A real case study is presented in this research. To meet the needs of this village we have proposed a mathematical optimization model using a CPLEX optimizer to generate the necessary energy power while minimizing the cost of energy (COE). In this study, different scenarios have been evaluated with respect to the existing energy availabilities, for example, in different periods of the year, demonstrated in terms of economic costs, the viability of resources such as biomass and biogas, and the viability of the energy production of wind power given the associated high costs. Finally, the effect of the use of renewable energy in consideration of CO2 emissions is studied in our research.
•We review the resource-constrained multi-project scheduling problem from its inception.•We propose a taxonomy to classify related literature based on problem features.•We classify and analyze ...solution methods and proposed benchmarks for this problem.•Related applications in real environments are discussed.
Project Management is becoming increasingly crucial in competitive environments such as manufacturing and the service industries. The Resource-Constrained Multi-Project Scheduling Problem (RCMPSP) consists of assigning start times to jobs corresponding to two or more projects that must be executed simultaneously while respecting the precedence between jobs and limited resources. The existing rise in the study of the RCMPSP resulted in numerous works on the topic while proposing different problem features. This research analyzes different variants of the problem based on aspects related to jobs, projects, relationships, resources, and time management. Moreover, based on the problem variants considered in the collected works, a taxonomy allowing (i) the identification and positioning of each RCMPSP variant and (ii) the analysis of the current state-of-the-art of the problem is proposed. In addition, the solution methods proposed to solve RCMPSPs are classified and analyzed, together with the benchmarks used to validate such approaches. Finally, this review paper discusses the RCMPSP connection to practice and provides future research opportunities in light of recent advances.
This study introduces a method for identifying territories ideal for establishing photovoltaic (PV) plants for green hydrogen (GH2) production in the Antofagasta region of northern Chile, a location ...celebrated for its outstanding solar energy potential. Assessing the viability of PV plant installation necessitates a balanced consideration of technical aspects and socio-environmental constraints, such as the proximity to areas of ecological importance and indigenous communities, to identify potential zones for solar and non-conventional renewable energy (NCRE)-based hydrogen production.
To tackle this challenge, we propose a methodology that utilizes geospatial analysis, integrating Geographic Information System (GIS) tools with sensitivity analysis, to determine the most suitable sites for PV plant installation in the Antofagasta region. Our geospatial analysis employs the QGIS software to identify these optimal locations, while sensitivity analysis uses the Sørensen–Dice coefficient method to assess the similarity among chosen socio-environmental variables.
Applying this methodology to the Antofagasta region reveals that a significant area within a 15 km radius of existing road networks and electrical substations is favorable for photovoltaic projects. Our sensitivity analysis further highlights the limiting effects of socio-environmental factors and their interactions. Moreover, our research finds that enlarging areas of socio-environmental importance could increase the total hydrogen production by about 10% per commune, indicating the impact of these factors on the potential for renewable energy production.
•Methodology for identifying suitable locations for installing green hydrogen PV plants.•Integrating socio-environmental and technical factors for green hydrogen plant installations.•Geospatial analysis through GIS to identify suitable locations for PV plants.•Sensitivity analysis to evaluate the similarity among socio-environmental factors.•Sustainable integration of green hydrogen in Chile’s energy transition.
PDF
