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Constrained multiobjective optimization problems (CMOPs) involve both conflicting objective functions and various constraints. Due to the presence of constraints, CMOPs' Pareto-optimal solutions are very likely lying on constraint boundaries. The experience from the constrained single-objective optimization has shown that to quickly obtain such an optimal solution, the search should surround the boundary of the feasible region from both the feasible and infeasible sides. In this article, we extend this idea to cope with CMOPs and, accordingly, we propose a novel constrained multiobjective evolutionary algorithm with bidirectional coevolution, called BiCo. BiCo maintains two populations, that is: 1) the main population and 2) the archive population. To update the main population, the constraint-domination principle is equipped with an NSGA-II variant to move the population into the feasible region and then to guide the population toward the Pareto front (PF) from the feasible side of the search space. While for updating the archive population, a nondominated sorting procedure and an angle-based selection scheme are conducted in sequence to drive the population toward the PF within the infeasible region while maintaining good diversity. As a result, BiCo can get close to the PF from two complementary directions. In addition, to coordinate the interaction between the main and archive populations, in BiCo, a restricted mating selection mechanism is developed to choose appropriate mating parents. Comprehensive experiments have been conducted on three sets of CMOP benchmark functions and six real-world CMOPs. The experimental results suggest that BiCo can obtain quite competitive performance in comparison to eight state-of-the-art-constrained multiobjective evolutionary optimizers.

Objectives The aim of this study was to explore the difference in target vessel failure (TVF) 3 years after intravascular ultrasound (IVUS) guidance versus angiographic guidance among all comers undergoing second-generation drug-eluting stent (DES) implantation. Background The multicenter randomized ULTIMATE (Intravascular Ultrasound Guided Drug Eluting Stents Implantation in “All-Comers” Coronary Lesions) trial showed a lower incidence of 1-year TVF after IVUS-guided DES implantation among all comers compared with angiographic guidance. However, the 3-year clinical outcomes of the ULTIMATE trial remain unknown. Methods A total of 1,448 all comers undergoing DES implantation who were randomly assigned to either IVUS guidance or angiographic guidance in the ULTIMATE trial were followed for 3 years. The primary endpoint was the risk for TVF at 3 years. The safety endpoint was definite or probable stent thrombosis (ST). Results At 3 years, TVF occurred in 47 patients (6.6%) in the IVUS-guided group and in 76 patients (10.7%) in the angiography-guided group (p = 0.01), driven mainly by the decrease in clinically driven target vessel revascularization (4.5% vs. 6.9%; p = 0.05). The rate of definite or probable ST was 0.1% in the IVUS-guided group and 1.1% in the angiography-guided group (p = 0.02). Notably, the IVUS-defined optimal procedure was associated with a significant reduction in 3-year TVF relative to that with the suboptimal procedure. Conclusions IVUS-guided DES implantation was associated with significantly lower rates of TVF and ST during 3-year follow-up among all comers, particularly those who underwent the IVUS-defined optimal procedure compared with those with angiographic guidance. (Intravascular Ultrasound Guided Drug Eluting Stents Implantation in “All-Comers” Coronary Lesions; NCT02215915 )

This paper studies a multiuser cooperative mobile edge computing offloading (called CoMECO) system in a multiuser interference environment, in which delay-sensitive tasks may be executed on local devices, cooperative devices, or the primary MEC server. In this system, we jointly optimize the offloading decision and computation resource allocation for minimizing the total energy consumption of all mobile users under the delay constraint. If this problem is solved directly, the offloading decision and computation resource allocation are generally generated separately at the same time. Note, however, that they are closely coupled. Therefore, under this condition, their dependency is not well considered, thus leading to poor performance. We transform this problem into a bilevel optimization problem, in which the offloading decision is generated in the upper level, and then the optimal allocation of computation resources is obtained in the lower level based on the given offloading decision. In this way, the dependency between the offloading decision and computation resource allocation can be fully taken into account. Subsequently, a bilevel optimization approach, called BiJOR, is proposed. In BiJOR, candidate modes are first pruned to reduce the number of infeasible offloading decisions. Afterward, the upper-level optimization problem is solved by ant colony system (ACS). Furthermore, a sorting strategy is incorporated into ACS to construct feasible offloading decisions with a higher probability and a local search operator is designed in ACS to accelerate the convergence. For the lower-level optimization problem, it is solved by the monotonic optimization method. In addition, BiJOR is extended to deal with a complex scenario with the channel selection. Extensive experiments are carried out to investigate the performance of BiJOR on two sets of instances with up to 400 mobile users. The experimental results demonstrate the effectiveness of BiJOR and the superiority of the CoMECO system.

A major performance index for analyzing a stochastic transport network is the two-terminal capacity reliability Rd, defined as the probability that d units of goods can be successfully transported via stochastic arc capacities from the source to the destination. This paper presents an efficient d-minimal path method to calculate Rd based on some newly obtained results. The proposed method uses a simple method to check d-minimal path candidates and a more efficient approach to remove duplicate d-minimal paths that are the biggest obstacle in solving d-minimal paths, along with an indication of the advantage over the existing methods. Besides, sensitivity analysis is adopted to explore the most important arc whose reliability change affects the network reliability most significantly, which helps supervisor identify and enhance the critical arcs for improving the network reliability more effectively. Computational and application examples demonstrate the efficiency and utility of the method, respectively.

Constrained multiobjective optimization problems (CMOPs) are frequently encountered in real-world applications, which usually involve constraints in both the decision and objective spaces. However, current artificial CMOPs never consider constraints in the decision space (i.e., decision constraints) and constraints in the objective space (i.e., objective constraints) at the same time. As a result, they have a limited capability to simulate practical scenes. To remedy this issue, a set of CMOPs, named DOC, is constructed in this paper. It is the first attempt to consider both the decision and objective constraints simultaneously in the design of artificial CMOPs. Specifically, in DOC, various decision constraints (e.g., inequality constraints, equality constraints, linear constraints, and nonlinear constraints) are collected from real-world applications, thus making the feasible region in the decision space have different properties (e.g., nonlinear, extremely small, and multimodal). On the other hand, some simple and controllable objective constraints are devised to reduce the feasible region in the objective space and to make the Pareto front have diverse characteristics (e.g., continuous, discrete, mixed, and degenerate). As a whole, DOC poses a great challenge for a constrained multiobjective evolutionary algorithm (CMOEA) to obtain a set of well-distributed and well-converged feasible solutions. In order to enhance current CMOEAs’ performance on DOC, a simple and efficient two-phase framework, named ToP, is proposed in this paper. In ToP, the first phase is implemented to find the promising feasible area by transforming a CMOP into a constrained single-objective optimization problem. Then in the second phase, a specific CMOEA is executed to obtain the final solutions. ToP is applied to four state-of-the-art CMOEAs, and the experimental results suggest that it is quite effective.

Background Double kissing (DK) crush approach for patients with coronary bifurcation lesions, particularly localized at distal left main or lesions with increased complexity, is associated with significant reduction in clinical events when compared with provisional stenting. Recently, randomized clinical trial has demonstrated the net clinical benefits by intravascular ultrasound (IVUS)-guided implantation of drug-eluting stent in all-comers. However, the improvement in clinical outcome after DK crush treatment guided by IVUS over angiography guidance for patients with complex bifurcation lesions have never been studied in a randomized fashion. Trial design DKCRUSH VIII study is a prospective, multicenter, randomized controlled trial designed to assess superiority of IVUS-guided vs angiography-guided DK crush stenting in patients with complex bifurcation lesions according to DEFINITION criteria. A total of 556 patients with complex bifurcation lesions will be randomly (1:1 of ratio) assigned to IVUS-guided or angiography-guided DK crush stenting group. The primary end point is the rate of 12-month target vessel failure, including cardiac death, target vessel myocardial infarction, or clinically driven target vessel revascularization. The secondary end points consist of the individual component of primary end point, all-cause death, myocardial infarction, and in-stent restenosis. The safety end point is the incidence of definite or probable stent thrombosis. An angiographic follow-up will be performed for all patients at 13 months and clinical follow-up will be continued annually until 3 years after the index procedure. Conclusions DKCRUSH VIII trial is the first study designed to evaluate the differences in efficacy and safety between IVUS-guided and angiography-guided DK crush stenting in patients with complex true bifurcation lesions. This study will also provide IVUS-derived criteria to define optimal DK crush stenting for bifurcation lesions at higher complexity.

Aim The present study aimed to assess the benefits of two-stent techniques for patients with DEFINITION criteria-defined complex coronary bifurcation lesions. Methods and results In total, 653 patients with complex bifurcation lesions at 49 international centres were randomly assigned to undergo the systematic two-stent technique (two-stent group) or provisional stenting (provisional group). The primary endpoint was the composite of target lesion failure (TLF) at the 1-year follow-up, including cardiac death, target vessel myocardial infarction (TVMI), and clinically driven target lesion revascularization (TLR). The safety endpoint was definite or probable stent thrombosis. At the 1-year follow-up, TLF occurred in 37 (11.4%) and 20 (6.1%) patients in the provisional and two-stent groups, respectively [77.8%: double-kissing crush; hazard ratio (HR) 0.52, 95% confidence interval (CI) 0.30–0.90; P = 0.019], largely driven by increased TVMI (7.1%, HR 0.43, 95% CI 0.20–0.90; P = 0.025) and clinically driven TLR (5.5%, HR 0.43, 95% CI 0.19–1.00; P = 0.049) in the provisional group. At the 1 year after indexed procedures, the incidence of cardiac death was 2.5% in the provisional group, non-significant to 2.1% in the two-stent group (HR 0.86, 95% CI 0.31–2.37; P = 0.772). Conclusion For DEFINITION criteria-defined complex coronary bifurcation lesions, the systematic two-stent approach was associated with a significant improvement in clinical outcomes compared with the provisional stenting approach. Further study is urgently warranted to identify the mechanisms contributing to the increased rate of TVMI after provisional stenting. Study registration http://www.clinicaltrials.com; Identifier: NCT02284750.

Background Intravascular ultrasound (IVUS)-guided drug-eluting stent (DES) implantation is associated with fewer major adverse cardiovascular events compared with angiography guidance for patients with individual lesion subset. However, the beneficial effect on major adverse cardiovascular event outcome of IVUS guidance over angiography guidance in all-comers who undergo DES implantation still remains understudied. Objectives This study aimed to determine the benefits of IVUS guidance over angiography guidance during DES implantation in all-comer patients. Methods A total of 1,448 all-comer patients who required DES implantation were randomly assigned (1:1 ratio) to either an IVUS guidance or angiography guidance group. The primary endpoint was target-vessel failure (TVF) at 12 months, including cardiac death, target-vessel myocardial infarction, and clinically driven target-vessel revascularization (TVR). The procedure was defined as a success if all IVUS-defined optimal criteria were met. Results At 12 months follow-up, 60 TVFs (4.2%) occurred, with 21 (2.9%) in the IVUS group and 39 (5.4%) in the angiography group (hazard ratio [HR]: 0.530; 95% confidence interval [CI]: 0.312 to 0.901; p = 0.019). In the IVUS group, TVF was recorded in 1.6% of patients with successful procedures, compared with 4.4% in patients who failed to achieve all optimal criteria (HR: 0.349; 95% CI: 0.135 to 0.898; p = 0.029). The significant reduction of clinically driven target-lesion revascularization or definite stent thrombosis (HR: 0.407; 95% CI: 0.188 to 0.880; p = 0.018) based on lesion-level analysis by IVUS guidance was not achieved when the patient-level analysis was performed. Conclusions The present study demonstrates that IVUS-guided DES implantation significantly improved clinical outcome in all-comers, particularly for patients who had an IVUS-defined optimal procedure, compared with angiography guidance. (Intravascular Ultrasound Guided Drug Eluting Stents Implantation in “All-Comers” Coronary Lesions [ULTIMATE]; NCT02215915)

In the framework of Industry 4.0, collaborative manufacturing across different supply chains is one of the most important business models. In order to avoid the uneven distribution of service requirements among service providers (i.e., non-equalization phenomenon), a lot of service strategies with different characteristics can be taken as candidate solutions to adjust the matching between service providers and service consumers. Based on the background, how to identify the application conditions of various service strategies in complex environment has become a serious challenge in the field. To solve this problem, the computational experiment-based evaluation method is proposed in this paper, including customization of service strategy, construction of experiment system, and experiment analysis of service strategy. In this paper, three possible service strategies are built to deal with the non-equalization phenomenon, i.e., non-equalization strategy, equalization strategy, collaborative equalization strategy. Experiment results show that: collaborative equalization strategy can effectively enhance the service utilization rate and reduce the completion time in short supply environment; equalization strategy is the optimal one in oversupply market environment. This case study can show that the proposed method is feasible and the result is satisfactory.

Feature selection is of particular importance in the field of drug discovery. Many methods have been put forward for feature selection during recent decades. Among them, evolutionary computation has gained increasing attention owing to its superior global search ability. However, there still lacks a simple and efficient software for drug developers to take advantage of evolutionary computation for feature selection. To remedy this issue, in this paper, a user-friendly and standalone software, named ECoFFeS, is developed. ECoFFeS is expected to lower the entry barrier for drug developers to deal with feature selection problems at hand by using evolutionary algorithms. To the best of our knowledge, it is the first software integrating a set of evolutionary algorithms (including two modified evolutionary algorithms proposed by the authors) with various evaluation combinations for feature selection. Specifically, ECoFFeS considers both single-objective and multi-objective evolutionary algorithms, and both regression- and classification-based models to meet different requirements. Five data sets in drug discovery are collected in ECoFFeS. In addition, to reduce the total analysis time, the parallel execution technique is incorporated into ECoFFeS. The source code of ECoFFeS can be available from https://github.com/JiaweiHuang/ECoFFeS/ .

A challenging research topic in wireless sensor network is prolonging the network lifetime by optimizing the network energy expenditure. The paper explores an enhanced energy optimization routing protocol which uses double cluster heads in a clustering wireless sensor network. The double cluster heads which are determined by energy welfare function are referred to as main cluster head and assistant one, respectively. To balance nodes energy, a formula for the energy overhead is presented to make the sensor node join a temporary cluster with low energy consuming during cluster set-up stage. Then, during the routing selection, relay nodes communicate sensory information to the sink by using combining single-hop and multi-hop technology. The selection of relay nodes depends on the weight values involving information of residual energy, the number of nodes in the cluster, selected times as relay nodes, and a distance between two nodes. The improved protocol is evaluated via simulation experiments and compared with some existing protocols. The simulation results demonstrate that the proposed protocol outperforms the relevant protocols in energy utilization efficiency. Especially, the network lifetime is prolonged due to decreasing energy consuming of the cluster head.

Background: Provisional stenting (PS) is the most common technique used to treat distal left main (LM) bifurcation lesions in patients with unprotected LM coronary artery disease undergoing...

Summary Background Cholangiocarcinoma (CCA) is a common biliary malignancy that results in high mortality and poor survival rates. The diagnostic capacity of miRNAs in CCA detection is still controversial. Current meta-analysis evaluate the evidence on the capacity of miRNAs for CCA diagnosis. Methods A systematic literature search for relevant articles in PubMed, Embase and Web of science database up to 10 April 2016 was conducted. The pooled sensitivity, specificity, positive and negative likelihood ratios (PLR and NLR, respectively), diagnostic odds ratio (DOR) and area under the curve (AUC) were pooled to assess the overall diagnostic value of miRNA. Subgroup analysis was further applied to explore the between-study heterogeneity. Publication bias was assessed with Deeks’ funnel plot. Statistical analysis was carried out using RevMan 5.2 and MetaDisc 1.4. Results A total of 501 patients and 248 controls from 14 studies in 8 articles were included in this meta-analysis. The pooled sensitivity and specialty were 0.83 (0.80–0.86) and 0.79 (0.75–0.83), respectively. The pooled PLR was 3.96 (2.64–5.94), NLR was 0.25 (0.19–0.34), DOR was 18.1 (9.79–33.5) and pooled AUC was 0.88 (0.85–0.90). Subgroup analyses indicated that the serum miRNA assays showed highly accurate CCA diagnosis. The diagnostic capacity was more accurate in Caucasians than in Asians. Conclusions The miRNA assays are promising diagnostic tools for CCA detection with moderate accuracy. However, further prospective studies were needed to confirm this results before clinical application.

Background Provisional stenting (PS) is effective for great majority of patients with coronary bifurcation lesions. Double kissing (DK) crush approach demonstrated significant reduction of target lesion revascularization (TLR) for patients with more complex bifurcation lesion when compared with PS. Furthermore, DK crush technique was associated with lower rate of composite major adverse cardiac event (MACE), revascularization and stent thrombosis (ST) for patients with unprotected distal left main coronary artery bifurcation lesions (ULMb), compared to culotte stenting approach. The DKCRUSH V trial is designed to elucidate the benefits of DK crush over PS in patients with ULMb. Study design DKCRUSH V is a randomized, prospective, multinational clinical trial designed to evaluate the efficacy and safety of DK crush over PS for patients with ULMb. Subjects with Medina 1,1,1 or 0,1,1 ULMb will be randomized in a 1:1 fashion to PS or DK crush. The primary endpoint is target lesion failure (TLF) including target vessel myocardial infarction, cardiac death and TLR. Other endpoints address individual event of primary endpoint, and target vessel revascularization. The safety objective is the ST. Recruitment began in January 2012 and was completed in December 2015; 484 patients were randomized. The trial will continue until at least 56 adjudicated primary endpoints occur. Conclusions The DKCRUSH V study is investigating if DK crush approach versus PS will reduce the incidence of TLF in patients with symptomatic ULMb.

The present study aimed to analyze the incidence of SF and its correlation with clinical events after DES implantation and the outcome of re-intervention for symptomatic in-stent restenosis (ISR) induced by stent fracture (SF).SF is associated with a high rate of clinical events after the implantation of drug-eluting stents (DES). However, the chronological rate of SF and the effect of SF on clinical outcomes from a large patient population remain underreported.A total of 6,555 patients with 16482 DES in 10751 diseased vessels and surveillance angiography between November 2003 and January 2014 were prospectively studied. The primary endpoints included the incidence of SF, in-stent restenosis (ISR), target lesion revascularization (TLR), and definite stent thrombosis (ST) at the end of follow-up before and after propensity score matching. Clinical outcomes after TLR were also followed up.The SF rate was detected in 803 (12.3%) patients, 3,630 (22.0%) stents, and 1,852 (17.2%) diseased vessels. SF increased over time. SF was associated with higher unadjusted rates of ISR (42.1%), TLR (24.8%, n = 379), and definite ST (4.6%) compared with stents without fracture (10.7%, 6.6%, and 1.03%, all p 0.001), and the differences remained significant after propensity score matching (all p 0.05). There was no significant difference in any-cause or cardiac mortality between patients with and without SF. After 1,523 days of follow-up since the first surveillance angiography, repeat ISR was detected in 90 of 379 (23.8%) stents after reintervention, and 6 (7.5%) stents required repeat TLR.SF is more frequently observed after DES implantation. TLR was required in almost one-fourth of fractured stents. Increased events in the SF group did not translate into a difference in mortality compared with the non-SF group. Reintervention was associated with acceptable clinical results.