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In the last few years, there have been notable developments in organic solar cells using both small molecule donor and acceptor. It has been noted that adding halogens to the end groups of small molecules could enhance the film structure and, consequently, the performance of the devices. In this study, three novel small molecule donors are created. The molecules include a vinyl‐CPDT oligomer with three units, with end‐caps made up of indanedione groups and containing four H, four Cl, and four F substituents. The purpose of the study is to investigate how the halogen substituent affects the photovoltaic characteristics of binary devices made with the non‐fullerene acceptor (NFA) TOCR2 as the acceptor. Having the halogen in the device enhances its effectiveness, and FG5, which has 4‐Cl substituents in the end groups, shows the highest efficiency among all devices with a PCE of 14.39%. Incredibly, the ternary device that is created in normal atmospheric conditions with chloro‐substituted FG5 as the donor, TOCR2 as the acceptor, and the wide band gap NFA DICTF as the third element shows significantly improved efficiency, achieving PCE values of up to 16.35%. [ABSTRACT FROM AUTHOR]

The team orienteering problem (TOP) is an NP‐hard optimization problem with an increasing number of potential applications in smart cities, humanitarian logistics, wildfire surveillance, etc. In the TOP, a fixed fleet of vehicles is employed to obtain rewards by visiting nodes in a network. All vehicles share common origin and destination locations. Since each vehicle has a limitation in time or traveling distance, not all nodes in the network can be visited. Hence, the goal is focused on the maximization of the collected reward, taking into account the aforementioned constraints. Most of the existing literature on the TOP focuses on its deterministic version, where rewards and travel times are assumed to be predefined values. This paper focuses on a more realistic TOP version, where travel times are modeled as random variables, which introduces reliability issues in the solutions due to the route‐length constraint. In order to deal with these complexities, we propose a simheuristic algorithm that hybridizes biased‐randomized heuristics with a variable neighborhood search and MCS. To test the quality of the solutions generated by the proposed simheuristic approach, we employ the well‐known sample average approximation (SAA) method, as well as a combination model that hybridizes the metaheuristic used in the simheuristic approach with the SAA algorithm. The results show that our proposed simheuristic outperforms the SAA and the hybrid model both on the objective function values and computational time. [ABSTRACT FROM AUTHOR]

This paper introduces the three‐dimensional case picking problem (3D‐CPP) and proposes a multistart biased‐randomized algorithm (BRA) to solve it. The 3D‐CPP combines two important topics in modern warehouse logistics: the pallet loading problem and the routing of pickers in manual warehouses. The proposed optimization procedure aims at minimizing the overall distance traveled by the pickers, and is achieved by combining a routing problem (i.e., the order in which picking positions are visited) with a loading problem (i.e., the way in which cases are placed onto the pallet). We also consider additional constraints regarding the weight, vertical support, and strength of the cases. In order to solve this problem, we first propose a constructive heuristic which combines routing and packing procedures. This initial heuristic is then extended into a multistart BRA by employing a skewed probability distribution to introduce a certain degree of randomness during the solution‐construction process. A series of computational experiments allow us to assess the quality of the proposed approach, through a comparison with other algorithms as well as using real‐life data provided by an industrial partner. [ABSTRACT FROM AUTHOR]

Stochastic, as well as fuzzy uncertainty, can be found in most real‐world systems. Considering both types of uncertainties simultaneously makes optimization problems incredibly challenging. In this paper we propose a fuzzy simheuristic to solve the Time Capacitated Arc Routing Problem (TCARP) when the nature of the travel time can either be deterministic, stochastic or fuzzy. The main goal is to find a solution (vehicle routes) that minimizes the total time spent in servicing the required arcs. However, due to uncertainty, other characteristics of the solution are also considered. In particular, we illustrate how reliability concepts can enrich the probabilistic information given to decision‐makers. In order to solve the aforementioned optimization problem, we extend the concept of simheuristic framework so it can also include fuzzy elements. Hence, both stochastic and fuzzy uncertainty are simultaneously incorporated into the CARP. In order to test our approach, classical CARP instances have been adapted and extended so that customers' demands become either stochastic or fuzzy. The experimental results show the effectiveness of the proposed approach when compared with more traditional ones. In particular, our fuzzy simheuristic is capable of generating new best‐known solutions for the stochastic versions of some instances belonging to the tegl, tcarp, val, and rural benchmarks. [ABSTRACT FROM AUTHOR]

Metaheuristic algorithms are employed to solve complex and large‐scale optimization problems in many different fields, from transportation and smart cities to finance. This paper discusses how metaheuristic algorithms are being applied to solve different optimization problems in the area of bioinformatics. While the text provides references to many optimization problems in the area, it focuses on those that have attracted more interest from the optimization community. Among the problems analyzed, the paper discusses in more detail the molecular docking problem, the protein structure prediction, phylogenetic inference, and different string problems. In addition, references to other relevant optimization problems are also given, including those related to medical imaging or gene selection for classification. From the previous analysis, the paper generates insights on research opportunities for the Operations Research and Computer Science communities in the field of bioinformatics. [ABSTRACT FROM AUTHOR]

The location routing problem (LRP) integrates operational decisions on vehicle routing operations with strategic decisions on the location of the facilities or depots from which the distribution will take place. In other words, it combines the well-known vehicle routing problem (VRP) with the facility location problem (FLP). Hence, the LRP is an NP-hard combinatorial optimization problem, which justifies the use of metaheuristic approaches whenever large-scale instances need to be solved. In this paper, we explore a realistic version of the LRP in which facilities of different capacities are considered, i.e., the manager has to consider not only the location but also the size of the facilities to open. In order to tackle this optimization problem, three mixed-integer linear formulations are proposed and compared. As expected, they have been proved to be cost- and time- inefficient. Hence, a biased-randomized iterated local search algorithm is proposed. Classical instances for the LRP with homogeneous facilities are naturally extended to test the performance of our approach. [ABSTRACT FROM AUTHOR]

The uncapacitated facility location problem (UFLP) is a popular NP‐hard optimization problem that has been traditionally applied to logistics and supply networks, where decisions are difficult to reverse. However, over the years, many new application domains have emerged, in which real‐time optimization is needed, such as Internet of Vehicles (IoV), virtual network functions placement, and network controller placement. IoV scenarios take into account the presence of multiple roadside units (RSUs) that should be frequently assigned to operating vehicles. To ensure the desired quality of service level, the allocation process needs to be carried out frequently and efficiently, as vehicles' demands change. In this dynamic environment, the mapping of vehicles to RSUs needs to be reoptimized periodically over time. Thus, this article proposes an agile optimization algorithm, which is tested using existing benchmark instances. The experiments show that it can efficiently generate high‐quality and real‐time results in dynamic IoV scenarios. [ABSTRACT FROM AUTHOR]

We show that in HD, active DBS modulates theta/alpha and beta band suppression in the GPi, and we provide evidence on a clear clinical improvement after intervention. (C) Wavelet transformation of 10-seconds data into time-frequency domain showing the equivalent suppression DBS-ON of the theta/alpha frequency band and decrease of the low beta band predominating along LFP recordings. Keywords: LFPs; Huntington's disease; deep brain stimulation; DBS; GPi EN LFPs Huntington's disease deep brain stimulation DBS GPi 518 520 3 03/23/23 20230301 NES 230301 Bilateral globus pallidus internus (GPi) deep brain stimulation (DBS) has been used for the treatment of hyperkinetic symptoms in Huntington's disease (HD).[[1], [3]] However, unlike other movement disorders, there is limited knowledge about the profile of frequency bands that predominate in the GPi in HD and about the effect of DBS on these frequency bands and on related clinical outcomes.[4] In previous studies of HD, local field potentials (LFPs) of the GPi recorded during OFF stimulation (DBS-OFF) showed a dominant theta/alpha activity similar to that observed in other hyperkinetic disorders.[[5]] In the present study, taking advantage of the capabilities of the new Medtronic PERCEPT implantable pulse generator (Medtronic, Minneapolis, MN),[7] we obtained LFPs of the GPi during DBS-OFF and DBS-ON in a gene-mutation carrier (CAG = 43), 43-year-old woman with symptomatic HD, characterized by pharmacologically uncontrollable choreatic movements in both the upper and lower extremities, dystonia, constant right-arm complex motor stereotypes, and vocalizations (Unified Huntington's Disease Rating Scale [UHDRS] total motor score = 82). [Extracted from the article]

Project portfolio management and optimization constitutes a critical activity for organizations in different industrial sectors and business. The scientific literature in this subject is extremely vast, which makes it difficult to understand the connections among the existing approaches and perspectives. This paper provides a clustering map of the existing work on the subject, thus identifying the main trends and approaches from different scientific communities. After analyzing each of the identified clusters, the paper provides insights and emerging trends that can be useful both for researchers and practitioners in the area. [ABSTRACT FROM AUTHOR]

This paper analyzes the permutation flow‐shop problem with delivery dates and cumulative payoffs (whenever these dates are met) under uncertainty conditions. In particular, the paper considers the realistic situation in which processing times are stochastic. The main goal is to find the permutation of jobs that maximizes the expected payoff. In order to achieve this goal, the paper first proposes a biased‐randomized heuristic for the deterministic version of the problem. Then, this heuristic is extended into a metaheuristic by encapsulating it into a variable neighborhood descent framework. Finally, the metaheuristic is extended into a simheuristic by incorporating Monte Carlo simulations. According to the computational experiments, the level of uncertainty has a direct impact on the solutions provided by the simheuristic. Moreover, a risk analysis is performed using two well‐known metrics: the value‐at‐risk and conditional value‐at‐risk. [ABSTRACT FROM AUTHOR]

In this paper, we consider a vehicle routing problem in which a fleet of homogeneous vehicles, initially located at a depot, has to satisfy customers' demands in a two‐echelon network: first, the vehicles have to visit intermediate nodes (e.g., a retail center or a consolidation center), where they deliver raw materials or bulk products and collect a number of processed items requested by the customers in their route; then, the vehicles proceed to complete their assigned routes, thus delivering the processed items to the final customers before returning to the depot. During this stage, vehicles might visit other intermediate nodes for reloading new items. In some real‐life scenarios, this problem needs to be solved in just a few seconds or even milliseconds, which leads to the concept of "agile optimization." This might be the case in some rescue operations using drones in humanitarian logistics, where every second can be decisive to save lives. In order to deal with this real‐time two‐echelon vehicle routing problem with pickup and delivery, an original constructive heuristic is proposed. This heuristic is able to provide a feasible and reasonably good solution in just a few milliseconds. The constructive heuristic is extended into a biased‐randomized algorithm using a skewed probability distribution to modify its greedy behavior. This way, parallel runs of the algorithm are able to generate even better results without violating the real‐time constraint. Results show that the proposed methodology generates competitive results in milliseconds, being able to outperform other heuristics from the literature. [ABSTRACT FROM AUTHOR]

In the context of a supply chain for the animal‐feed industry, this paper focuses on optimizing replenishment strategies for silos in multiple farms. Assuming that a supply chain is essentially a value chain, our work aims at narrowing this chasm and putting analytics into practice by identifying and quantifying improvements on specific stages of an animal‐feed supply chain. Motivated by a real‐life case, the paper analyses a rich multi‐period inventory routing problem with homogeneous fleet, stochastic demands, and maximum route length. After describing the problem and reviewing the related literature, we introduce a reactive heuristic, which is then extended into a biased‐randomized simheuristic. Our reactive approach is validated and tested using a series of adapted instances to explore the gap between the solutions it provides and the ones generated by existing nonreactive approaches. [ABSTRACT FROM AUTHOR]

Modern production systems require multiple manufacturing centers—usually distributed among different locations—where the outcomes of each center need to be assembled to generate the final product. This paper discusses the distributed assembly permutation flow‐shop scheduling problem, which consists of two stages: the first stage is composed of several production factories, each of them with a flow‐shop configuration; in the second stage, the outcomes of each flow‐shop are assembled into a final product. The goal here is to minimize the makespan of the entire manufacturing process. With this objective in mind, we present an efficient and parameter‐less algorithm that makes use of a biased‐randomized iterated local search metaheuristic. The efficiency of the proposed method is evaluated through the analysis of an extensive set of computational experiments. The results show that our algorithm offers excellent performance when compared with other state‐of‐the‐art approaches, obtaining several new best solutions. [ABSTRACT FROM AUTHOR]

The inventory routing problem (IRP) combines inventory management and delivery route‐planning decisions. This work presents a simheuristic approach that integrates Monte Carlo simulation within a variable neighborhood search (VNS) framework to solve the multiperiod IRP with stochastic customer demands. In this realistic variant of the problem, our goal is to establish the optimal refill policies for each customer–period combination, that is, those individual refill policies that minimize the total expected cost over the periods. This cost is the aggregation of both expected inventory and routing costs. Our simheuristic algorithm allows to consider the inventory changes between periods generated by the realization of the random demands in each period, which have an impact on the quantities to be delivered in the next period and, therefore, on the associated routing plans. A range of computational experiments are carried out in order to illustrate the potential of our simulation–optimization approach. [ABSTRACT FROM AUTHOR]

In supermarkets, perishable products need to be sold to consumers before a given deadline, after which their monetary value is significantly diminished or even completely lost. In the case of valuable products that should not be wasted, the following operational decision needs to be made as this deadline approaches: which is the best way to reallocate products from stores with surplus inventories to stores with unsatisfied demand? This question results in an optimization problem in which the goal is to minimize total transport cost plus opportunity cost associated with a reduction in market value of products being delivered after a given deadline. Our paper examines this inventory reallocation problem, which is modeled as an extension of the multi‐depot vehicle routing problem with soft deadlines, that is, delivery deadlines can be violated by incurring an opportunity or penalty cost. Being an NP‐hard optimization problem, a metaheuristic algorithm using biased‐randomization techniques is proposed as an effective solution approach. A series of computational experiments contribute to validate our algorithm and to illustrate the potential benefits that can be obtained by reallocating perishable and valuable products in various problem settings. [ABSTRACT FROM AUTHOR]

When capacity constraints have to be considered at each depot due to the existence of a limited number of capacitated vehicles, the multidepot vehicle routing problem (MDVRP) is a nontrivial extension of the well‐known capacitated vehicle routing problem (CVRP). The MDVRP combines a customer‐to‐depot assignment problem with several CVRPs. In real‐life scenarios, it is usual to find uncertainty in the customers' demands. There are few works on the stochastic MDVRP (SMDVRP) and, to the best of our knowledge, most of them assume the existence of an unlimited fleet of vehicles at each depot. This paper presents a simheuristic framework combining Monte Carlo simulation with a metaheuristic algorithm to deal with the SMDVRP with limited fleets (and, therefore, limited depot serving capacity). Its efficiency is tested on a set of stochastic instances, which extend the ones available in the literature for the deterministic version of the problem. [ABSTRACT FROM AUTHOR]

In a global and competitive economy, efficient supply networks are essential for modern enterprises. Horizontal cooperation (HC) concepts represent a promising strategy to increase the performance of supply chains. HC is based on sharing resources and making joint decisions among different agents at the same level of the supply chain. This paper analyzes different cooperation scenarios concerning integrated routing and facility‐location decisions in road transportation: (a) a noncooperative scenario in which all decisions are individually taken (each enterprise addresses its own vehicle routing problem [VRP]); (b) a semicooperative scenario in which route‐planning decisions are jointly taken (facilities and fleets are shared and enterprises face a joint multidepot VRP); and (c) a fully cooperative scenario in which route‐planning and facility‐location decisions are jointly taken (also customers are shared, and thus enterprises face a general location routing problem). Our analysis explores how this increasing level of HC leads to a higher flexibility and, therefore, to a lower total distribution cost. A hybrid metaheuristic algorithm, combining biased randomization with a variable neighborhood search framework, is proposed to solve each scenario. This allows us to quantify the differences among these scenarios, both in terms of monetary and environmental costs. Our solving approach is tested on a range of benchmark instances, outperforming previously reported results. [ABSTRACT FROM AUTHOR]

e‐Commerce activity has been increasing during recent years, and this trend is expected to continue in the near future. e‐Commerce practices are subject to uncertainty conditions and high variability in customers' demands. Considering these characteristics, we propose two facility–location models that represent alternative distribution policies in e‐commerce (one based on outsourcing and another based on in‐house distribution). These models take into account stochastic demands as well as more than one regular supplier per customer. Two methodologies are then introduced to solve these stochastic versions of the well‐known capacitated facility–location problem. The first is a two‐stage stochastic‐programming approach that uses an exact solver. However, we show that this approach is not appropriate for tackle large‐scale instances due to the computational effort required. Accordingly, we also introduce a "simheuristic" approach that is able to deal with large‐scale instances in short computing times. An extensive set of benchmark instances contribute to illustrate the efficiency of our approach, as well as its potential utility in modern e‐commerce practices. [ABSTRACT FROM AUTHOR]

Abstract: This paper analyzes the fleet mixed vehicle‐routing problem with backhauls, a rich and realistic variant of the popular vehicle‐routing problem in which both delivery and pick‐up customers are served from a central depot using a heterogeneous and configurable fleet of vehicles. After a literature review on the issue and a detailed description of the problem, a solution based on a multistart biased‐randomized heuristic is proposed. Our algorithm uses an iterative method that relies on solving a series of smaller instances of the homogeneous‐fleet version of the problem and then using these subsolutions as partial solutions for the original heterogeneous instance. In order to better guide the exploration of the solutions space, the algorithm employs several biased‐randomized processes: a first one for selecting a vehicle type; a second one for sorting the savings list; and a third one to define the number of routes that must be selected from the homogenous‐fleet subsolution. The computational experiments show that our approach is competitive and able to provide 20 new best‐known solutions for a 36‐instance benchmark recently proposed in the literature. [ABSTRACT FROM AUTHOR]

The location routing problem (LRP) involves the three key decision levels in supply chain design, that is, strategic, tactical, and operational levels. It deals with the simultaneous decisions of (a) locating facilities (e.g., depots or warehouses), (b) assigning customers to facilities, and (c) defining routes of vehicles departing from and finishing at each facility to serve the associated customers' demands. In this paper, a two-phase metaheuristic procedure is proposed to deal with the capacitated version of the LRP (CLRP). Here, decisions must be made taking into account limited capacities of both facilities and vehicles. In the first phase (selection of promising solutions), we determine the depots to be opened, perform a fast allocation of customers to open depots, and generate a complete CLRP solution using a fast routing heuristic. This phase is executed several times in order to keep the most promising solutions. In the second phase (solution refinement), for each of the selected solutions we apply a perturbation procedure to the customer allocation followed by a more intensive routing heuristic. Computational experiments are carried out using well-known instances from the literature. Results show that our approach is quite competitive since it offers average gaps below 0.4% with respect to the best-known solutions (BKSs) for all tested sets in short computational times. [ABSTRACT FROM AUTHOR]

This article analyzes the Vehicle Routing Problem with Backhauls, where delivery and pick-up customers are served from a central depot. Initially, we focus in the version with clustered backhauls (VRPCB), where all the customers in the delivery group of the same route have to be served before the first customer in the pick-up group can be visited. The article presents a relatively simple-to-implement yet efficient metaheuristic algorithm that integrates a biased-randomized version of the popular savings heuristic within a metaheuristic framework. A skewed probability distribution is used to induce a biased (oriented) randomization effect on the savings list of routing edges, and a penalty cost is assigned to those edges connecting delivery customers with pick-up customers in order to promote a sequential order in delivery and pick-up activities. In the proposed approach, the fleet size constraint is implicitly relaxed. This feature allows the perturbation process to explore unfeasible but promising regions in the solution space. Then, whenever the number of routes does not match the number of available vehicles, a 'recursive corrective operator' is employed to transform the new solution into a feasible one. Some classical benchmark instances for the VRPCB are selected in order to compare our approach with other state-of-the-art algorithms, and a new best-know solution for a classical benchmark set is obtained. Finally, we analyze the flexibility of our approach by employing it, after a minor adaptation, in the Vehicle Routing Problem with Mixed Backhauls, where linehaul and backhaul customers might appear in any order during a route. © 2017 Wiley Periodicals, Inc. NETWORKS, Vol. 69(3), 241-255 2017 [ABSTRACT FROM AUTHOR]

In this study, a new segmentation strategy is presented for the full-wave analysis of directly coupled cavity filters in substrate integrated waveguide (SIW) technology. The whole SIW filter is enclosed inside an external fictitious rectangular waveguide, which does not affect the propagation inside the SIW assuming that the SIW is well designed and there is no significant power leakage. The external rectangular waveguide allows to easily segment the structure into building blocks that are composed of circular metallic vias inside a rectangular waveguide. The generalised scattering matrix of these building blocks is obtained with highly efficient techniques specifically suited for the analysis of H-plane rectangular waveguide devices. Some building blocks are repeated along the structure, and their scattering matrix has to be computed only once. The scattering matrices of all the building blocks are cascaded and the scattering matrix of the whole filter is obtained. A SIW filter of eight coupled cavities with a bandpass response centred at 11 GHz is analysed. Results from this analysis show that the computational time has been significantly reduced when compared with other specific SIW analysis methods or with commercial general purpose software, while maintaining a good accuracy. [ABSTRACT FROM AUTHOR]

This paper proposes a hybrid approach for solving the multidepot vehicle routing problem (MDVRP) with a limited number of identical vehicles per depot. Our approach, which only uses a few parameters, combines 'biased randomization'-use of nonsymmetric probability distributions to generate randomness-with the iterated local search (ILS) metaheuristic. Two biased-randomized processes are employed at different stages of the ILS framework in order to (a) assign customers to depots following a randomized priority criterion-this allows for fast generation of alternative allocation maps and (b) improving routing solutions associated with a 'promising' allocation map-this is done by randomizing the classical savings heuristic. These biased-randomized processes rely on the use of the geometric probability distribution, which is characterized by a single and bounded parameter. Being an approach with few parameters, our algorithm does not require troublesome fine-tuning processes, which tend to be time consuming. Using standard benchmarks, the computational experiments show the efficiency of the proposed algorithm. Despite its hybrid nature, our approach is relatively easy to implement and can be parallelized in a very natural way, which makes it an interesting alternative for practical applications of the MDVRP. [ABSTRACT FROM AUTHOR]

This paper discusses horizontal cooperation in road transportation and supports the relevance of this praxis as a way of reducing delivery costs and greenhouse gas emissions. In a competitive market, costs reduction due to economies of scale in short and long run constitutes a key issue for small and medium enterprises. The paper reviews the existing literature on the topic and then examines different scenarios in order to quantify the savings in route costs that can be attained throughout horizontal cooperation. This numerical analysis is based on a set of well-known benchmarks for the Multidepot Vehicle Routing Problem, which has been adapted to illustrate a realistic but seldom considered example of horizontal cooperation. An Iterated Local Search algorithm is proposed to obtain high-quality solutions for this collaborative scenario, while noncollaborative scenarios are solved using a well-tested algorithm for the Capacitated Vehicle Routing Problem. The savings in routing costs-both regarding distance-based and environmental costs-are computed taking into account different geographical distributions of customers with respect to their assigned service providers. [ABSTRACT FROM AUTHOR]

Using synchrotron-based X-ray diffraction measurements, we identified crystalline material in two particles of extraterrestrial origin extracted from the Stardust Interstellar Dust Collector. The first particle, I1047,1,34 (Hylabrook), consisted of a mosaiced olivine grain approximately 1 µm in size with internal strain fields up to 0.3%. The unit cell dimensions were a = 4.85 ± 0.08 Å, b = 10.34 ± 0.16 Å, c = 6.08 ± 0.13 Å (2σ). The second particle, I1043,1,30 (Orion), contained an olivine grain ≈ 2 µm in length and >500 nm in width. It was polycrystalline with both mosaiced domains varying over ≈ 20 [ABSTRACT FROM AUTHOR]

Hard X-ray, quantitative, fluorescence elemental imaging was performed on the ID22 NI nanoprobe and ID22 microprobe beam lines of the European Synchrotron Research facility ( ESRF) in Grenoble, France, on eight interstellar candidate impact features in the framework of the NASA Stardust Interstellar Preliminary Examination ( ISPE). Three features were unambiguous tracks, and the other five were identified as possible, but not definite, impact features. Overall, we produced an absolute quantification of elemental abundances in the 15 ≤ Z ≤ 30 range by means of corrections of the beam parameters, reference materials, and fundamental atomic parameters. Seven features were ruled out as interstellar dust candidates ( ISDC) based on compositional arguments. One of the three tracks, I1043,1,30,0,0, contained, at the time of our analysis, two physically separated, micrometer-sized terminal particles, the most promising ISDCs, Orion and Sirius. We found that the Sirius particle was a fairly homogenous Ni-bearing particle and contained about 33 fg of distributed high-Z elements (Z > 12). Orion was a highly heterogeneous Fe-bearing particle and contained about 59 fg of heavy elements located in hundred nanometer phases, forming an irregular mantle that surrounded a low-Z core. X-ray diffraction ( XRD) measurements revealed Sirius to be amorphous, whereas Orion contained partially crystalline material (Gainsforth et al. 2014). Within the mantle, one grain was relatively Fe-Ni-Mn-rich; other zones were relatively Mn-Cr-Ti-rich and may correspond to different spinel populations. For absolute quantification purposes, Orion was assigned to a mineralogical assemblage of forsterite, spinel, and an unknown Fe-bearing phase, while Sirius was most likely composed of an amorphous Mg-bearing material with minor Ni and Fe. Owing to its nearly chondritic abundances of the nonvolatile elements Ca, Ti, Co, and Ni with respect to Fe, in combination with the presence of olivine and spinel as inferred from XRD measurements, Orion had a high probability of being extraterrestrial in origin. [ABSTRACT FROM AUTHOR]

This paper proposes an efficient algorithm, with a reduced number of parameters, for solving the two-dimensional loading-capacitated vehicle routing problem (2L-CVRP). This problem combines two of the most important issues in logistics, that is, vehicle routing and packing problems. Our approach contemplates unrestricted loading including the possibility of applying 90° rotations to each rectangular-shaped item while loading it into the vehicle, which is a realistic assumption seldom considered in the existing literature. The algorithm uses a multistart approach that is designed to avoid local minima and also to make the algorithm an easily parallelizable one. At each restart, a biased randomization of a savings-based routing algorithm is combined with an enhanced version of a classical packing heuristic to produce feasible good solutions for the 2L-CVRP. The proposed algorithm has been compared with the classical benchmarks for two different 2L-CVRP variants, that is, with and without item rotations. Experimental results show that our approach outperforms several best-known solutions from previous work, both in terms of quality and the computational time needed to obtain them. [ABSTRACT FROM AUTHOR]

Iterated local search (ILS) is a powerful framework for developing efficient algorithms for the permutation flow-shop problem (PFSP). These algorithms are relatively simple to implement and use very few parameters, which facilitates the associated fine-tuning process. Therefore, they constitute an attractive solution for real-life applications. In this paper, we discuss some parallelization, parametrization, and randomization issues related to ILS-based algorithms for solving the PFSP. In particular, the following research questions are analyzed: (a) Is it possible to simplify even more the parameter setting in an ILS framework without affecting performance? (b) How do parallelized versions of these algorithms behave as we simultaneously vary the number of different runs and the computation time? (c) For a parallelized version of these algorithms, is it worthwhile to randomize the initial solution so that different starting points are considered? (d) Are these algorithms affected by the use of a 'good-quality' pseudorandom number generator? In this paper, we introduce the new ILS-ESP (where ESP is efficient, simple, and parallelizable) algorithm that is specifically designed to take advantage of parallel computing, allowing us to obtain competitive results in 'real time' for all tested instances. The ILS-ESP also uses 'natural' parameters, which simplifies the calibration process. An extensive set of computational experiments has been carried out in order to answer the aforementioned research questions. [ABSTRACT FROM AUTHOR]

Translational and clinical cancer research, as well as clinical trials and treatment of cancer, are essentially structured based on the organ in which tumors originate. However, the recent explosion of knowledge about the molecular characteristics of tumors is opening a new way to tackle cancer. This article proposes a different approach to the classification of cancer with important implications for treatment and for basic, translational, and clinical research. The authors postulate that cancers from diverse organs of origin with similar molecular traits should be managed together. The common molecular features observed in different tumors determine clinical actions in a better way than organ-based classification. Thus, comparisons between tumors residing in different locations but with shared molecular characteristics will improve the therapeutic approach and the understanding of the biology of cancer. CA Cancer J Clin 2014;64:70-74. © 2013 American Cancer Society. [ABSTRACT FROM AUTHOR]

This paper presents an innovative academic experience regarding the use of PlanetLab-an open large-scale platform over the Internet-in engineering courses on distributed systems. By integrating a live-deployment environment such as PlanetLab into distributed-systems courses, software implementations developed by students can interact with instructors' implementations in a real Internet-distributed scenario. To the best of our knowledge, this is the first experience regarding the use of the PlanetLab nodes available over Internet to teach distributed computing concepts to engineering students, since most of the existing literature on distributed-systems courses describes only learning experiences in lab-simulated or lab-emulated scenarios. As discussed in this paper, experimenting with a real laboratory over the Internet adds some complexity to students' practical activities, but it also facilitates a deeper and more intensive learning experience. A survey among students shows some clear benefits of this approach over the use of simulation labs, as well as some pitfalls that must be avoided whenever possible. The paper ends with a set of recommendations for instructors that might want to design similar courses as well as with an overview of future work to be performed in this field. © 2010 Wiley Periodicals, Inc. Comput Appl Eng Educ 21: 265-275, 2013 [ABSTRACT FROM AUTHOR]

The ESRF synchrotron beamline ID22, dedicated to hard X-ray microanalysis and consisting of the combination of X-ray fluorescence, X-ray absorption spectroscopy, diffraction and 2D/3D X-ray imaging techniques, is one of the most versatile instruments in hard X-ray microscopy science. This paper describes the present beamline characteristics, recent technical developments, as well as a few scientific examples from recent years of the beamline operation. The upgrade plans to adapt the beamline to the growing needs of the user community are briefly discussed. [ABSTRACT FROM AUTHOR]

We base the ALGACEA-1 method on Clarke–Wright's savings estimates, using Monte Carlo techniques for node selection. This procedure controls the assigned probabilities for node selection using a bounded Entropy function. Similarly, we have discussed the parameter tuning for this method with the purpose of obtaining a good algorithm performance. Finally, some computational results are given to show the quality of the solutions provided by ALGACEA-1 in a real case and in some benchmarking instances. [ABSTRACT FROM AUTHOR]

There is extensive empirical research on the potential destabilizing effects of futures trading activity on spot market volatility. Rather than just focusing on spot volatility, the authors deal with the contemporaneous relationship between futures trading volume and the overall probability distribution of spot market returns. Empirical evidence using intraday data from the Spanish stock index futures market over the period 2000–2002 is provided. Their findings reveal that the density function of spot return conditional to spot volume depends on unexpected futures trading volume. [ABSTRACT FROM AUTHOR]

To ascertain the possible implications of the nitric oxide (NO•) producing system in striatal senescence, and by using immunohistochemistry and image-processing approaches, we describe the presence of the enzyme nitric oxide synthase (NOS), the NADPH-diaphorase (NADPH-d) histochemical marker, and nitrotyrosine-derived complexes (N-Tyr) in the striatum of adult and aged rats. The results showed neuronal NOS immunoreactive (nNOS-IR) aspiny medium-sized neurons and nervous fibres in both age groups, with no variation in the percentage of immunoreactive area but a significant decrease in the intensity and in the number of somata with age, which were not related to the observed increase with age of the striatal bundles of the white matter. In addition, NADPH-d activity was detected in neurons with morphology similar to that of the nNOS-IR cells; a decrease in the percentage of area per field and in the number of cells, but an increase in the intensity of staining for the NADPH-d histochemical marker, were detected with age. The number of neuronal NADPH-d somata was higher than for the nNOS-IR ones in both age groups. Moreover, N-Tyr-IR complexes were observed in cells (neurons and glia) and fibres, with a significant increase in the percentage of the area of immunoreaction, related to the increase of white matter, but a decrease in intensity for the aged group. On the other hand, we did not detect the inducible isoform (iNOS) either in adult or in aged rats. Taken together, these results support the contention that NADPH-d staining is not such an unambiguous marker for nNOS, and that increased protein nitration may participate in striatal aging. Microsc. Res. Tech. 64:304-311, 2004. © 2004 Wiley-Liss, Inc. [ABSTRACT FROM AUTHOR]

Objective: To determine the presence of eggs, larva, cysts and oocysts of intestinal parasites in the soil of a suburb of Neuquén city during 1 year in order to evaluate their seasonal fluctuations in relation to climatic data and soil characteristics in the studied area.Methods: A total of 107 soil samples were processed for parasite isolation by sedimentation and flotation methods during the four seasons of the year. Meteorological data were registered and physical, chemical and structural characteristics of the soil were analysed.Results: About 28.9% of the soil samples were positive for at least one parasite form. Six protozoa species (cysts of Entamoeba sp., Enteromonas sp., Endolimax sp., Giardia sp., Iodamoeba sp. and coccidia oocysts) were recovered, but neither larvae nor eggs of human or animal helminths parasites were detected. The percentage of contaminated soil samples and the diversity of species showed a marked decrease in the warm and dry months of the summer. The soil was sandy, without vegetable cover, well drained, and with scarce organic matter content.Conclusion: The frequencies of parasite recovery and the number of species show seasonal fluctuations related to the rainfall. The importance of soil as a risk factor for the transmission of intestinal parasites in the studied area is conditioned by its structural characteristics, which prevent retaining the humidity, and by climatic variables. The interrelation of both factors determines unfavourable conditions that could explain the low level of contamination observed in soil as well as the absence of eggs and helminth larvae. [ABSTRACT FROM AUTHOR]

The article presents a case study of a 47-year-old man with chronic alcoholism that complains of severe abdominal pain with vomiting and nausea after taking large amount of food and alcohol. The patient was diagnosed with intra-abdominal hypertension (IAH) with compression of the inferior vena cava caused by pancreatic pseudocyst (PP). The PP was decompressed and controlled through computed tomography (CT) by inserting two drainage tubes obtaining 2700 milliliter (ml) of gray liquid.

Presents a case report of a patient with diagnosis of systemic lupus erythematosus and secondary antiphospholipid syndrome who had a mass in the right atrium. Details of the case report; Description of the formation of thrombi; Image of the right atrium of the patient; Assessment of intracardiac masses.

A call for papers for the special issue of the "International Transactions of Operational Research," on metaheuristics is presented. [ABSTRACT FROM PUBLISHER]

Abstract: The hub location problem has gained attention over the last decades. In telecommunications network, a hub is a place of concurrence in where the work of the network is centralized with the purpose of delivering out the data that arrives from one or more directions to other destinations. There are different versions of the hub location problem depending upon (1) the existence or not of restrictions on the capacity related to the volume of flow a hub is allowed to support, (2) the existence or not of a set‐up cost associated with selecting any node as a hub, etc. In these types of configurations, the hubs serve as connection point between 2 installations, allowing, in this way, to replace a large amount of direct connections between all pair of the nodes, therefore, minimizing the total transportation cost of the network. Thus, this work proposes a 2‐stage metaheuristic based on the combination of biased‐randomized technique with an iterated local search framework for solving the uncapacitated single allocation p‐hub median problem, with computational results that validate the methodology for large‐size instances from the literature. [ABSTRACT FROM AUTHOR]

Our objective is to evaluate prevalence changes of overweight (OW) and obesity (O) in 12 to 19 year old women, using data from two National Nutrition Surveys (1999 and 2006). Both surveys have probabilistic complex design. We have data from 1799 teenagers for 1999 and 2683 for 2006. The nutritional status is calculated using the Body Mass Index (BMI = kg/m2). To classify female teenagers as being overweight or obese, we used the distribution and cutoff values proposed by the International Obesity Task Force (IOTF). We consider only data values between 10 and 58 kg/m 2 for BMI and -5.5 and 3.0 for HAZ. We observed a change in OW prevalence from 21.6 to 23.3 (7.8%). In O the change was from 6.9 to 9.2 (33.3%). It is estimated that by 2006 more than two millions of women suffer OW + O. The most important prevalence increase is around 17 years. The O prevalence in the last seven years in Mexican teenager women is alarming, because it occurs in all the age groups. It is urgent to apply strategies and programs focused in obesity control and prevention. [ABSTRACT FROM AUTHOR]

This study evaluate the effectiveness of a nation-wide program distributing milk fortified with 10 mg of iron (gluconate), 10 mg zinc (oxide), vitamin C and other micronutrients on the linear growth and body composition of 1084 Mexican toddlers 12-30 mo of age. Children were randomly assigned to receive daily either 500 mL of fortified milk for 2 years (FM2Y) or non-fortified milk for one year followed by fortified milk the second years (FM1Y), under the normal operation conditions of the program. A comparable third group that never received fortified milk was assembled the second year (C) selected from the same communities. Body height and weight at 0 and 2 years, and Fat-free mass (FFM) by impedanciometry, physical activity by accelerometry at 2 years after intervention were measured. Means from linear regression models, adjusting for basal measurements of the variables, age, sex, socioeconomic status and nesting within the communities were calculated. Prevalences were compared by X2. Means height (FM2Y=99.8±3.2 cm, FM1Y=99.3±3.3 cm vs C group=97.1± 3.1 cm, p<0,001); FFM (FM2Y=10.4±0.87 kg, FM1Y=10.3.7±0.87 kg vs 9.7±0.91 kg C, p<0.001); AF (FM2Y=288±115 kcal, FM1Y= 321±115 kcal and C=241±109 kcal, p<0.001) were higher in the FM2Y and FM1Y than in the C group. The basal prevalence of stunting lessened from 11.5 % to 6.3% FM2Y, 8.3% FM1Y and 11.9% in the C group. This program distributing milk fortified with iron and zinc to 5 million children demonstrated to be effective to improve the quantity and quality of growth. [ABSTRACT FROM AUTHOR]

This study evaluated the effectiveness of a Federal Government program that distributes milk fortified with 10 mg of iron (gluconate), 10 mg zinc (oxide), vitamin C and other micronutrients at subsidized prices on the prevalence of anemia and iron deficiency in 1084 Mexican toddlers 12-30 mo of age. Children were randomly assigned to receive daily either 500 mL of fortified milk for 2 years (FM2Y) or non-fortified milk for one year followed by fortified milk the second years (FM1Y), under the normal operation conditions of the program. A comparable third group that never received fortified milk was assembled the second year (C) selected from the same communities. Hemoglobin, serum ferritin (F), soluble transferrin receptors (sTfR) and PCR were measured a 0 and 2 years after initiation of intervention. The basal prevalence of anemia (41.4%) and iron deficiency (44%) decreased to 3.3 and 10%, respectively in FM2 and to 2.4 and 7.4%, respectively in FM groups. Final prevalences of anemia and iron deficiency were lower than in C group (9% and 16.1%, p¡Ü0.0001, and p¡Ü0.003, respectively). After three years of the implemented this highly effective program outreaching 5 million children, 1.5 million oh them were cured from anemia and iron deficiency and the associated loss of capacities was most probably curved. [ABSTRACT FROM AUTHOR]