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The cyclic GMP-AMP (cGAMP) synthase (cGAS)-stimulator of interferon genes (STING) pathway has a crucial role in combating pathogen infection. However, its aberrant activation is involved in several human disorders. Lysosomes are emerging as key negative regulators of cGAS-STING signaling. Here, we discuss the lysosomal control of cGAS-STING signaling and its implication in human disorders. [ABSTRACT FROM AUTHOR]

Objective. The accurate automatic segmentation of tumors from computed tomography (CT) volumes facilitates early diagnosis and treatment of patients. A significant challenge in tumor segmentation is the integration of the spatial correlations among multiple parts of a CT volume and the context relationship across multiple channels. Approach. We proposed a mutually enhanced multi-view information model (MEMI) to propagate and fuse the spatial correlations and the context relationship and then apply it to lung tumor CT segmentation. First, a feature map was obtained from segmentation backbone encoder, which contained many image region nodes. An attention mechanism from the region node perspective was presented to determine the impact of all the other nodes on a specific node and enhance the node attribute embedding. A gated convolution-based strategy was also designed to integrate the enhanced attributes and the original node features. Second, transformer across multiple channels was constructed to integrate the channel context relationship. Finally, since the encoded node attributes from the gated convolution view and those from the channel transformer view were complementary, an interaction attention mechanism was proposed to propagate the mutual information among the multiple views. Main results. The segmentation performance was evaluated on both public lung tumor dataset and private dataset collected from a hospital. The experimental results demonstrated that MEMI was superior to other compared segmentation methods. Ablation studies showed the contributions of node correlation learning, channel context relationship learning, and mutual information interaction across multiple views to the improved segmentation performance. Utilizing MEMI on multiple segmentation backbones also demonstrated MEMI's generalization ability. Significance. Our model improved the lung tumor segmentation performance by learning the correlations among multiple region nodes, integrating the channel context relationship, and mutual information enhancement from multiple views. [ABSTRACT FROM AUTHOR]

Liquid droplets hanging from solid surfaces are commonplace, but their physics is complex. Examples include dew or raindrops hanging onto wires or droplets accumulating onto a cover placed over warm food or windshields. In these scenarios, determining the force of detachment is crucial to rationally design technologies. Despite much research, a quantitative theoretical framework for detachment force remains elusive. In response, we interrogated the elemental droplet–surface system via comprehensive laboratory and computational experiments. The results reveal that the Young–Laplace equation can be utilized to accurately predict the droplet detachment force. When challenged against experiments with liquids of varying properties and droplet sizes, detaching from smooth and microtextured surfaces of wetting and non-wetting chemical make-ups, the predictions were in an excellent quantitative agreement. This study advances the current understanding of droplet physics and will contribute to the rational development of technologies. Understanding the physics that govern the dynamics of liquid droplets and their interaction with solid surfaces is crucial for a range of industrial applications, from pesticides to solar cells. Here, the authors develop a framework based on the Young-Laplace equation, to predict the force required to detach a drop from flat and microstructured solid surfaces. [ABSTRACT FROM AUTHOR]

Liquid droplets hanging from solid surfaces are commonplace, but their physics is complex. Examples include dew or raindrops hanging onto wires or droplets accumulating onto a cover placed over warm food or windshields. In these scenarios, determining the force of detachment is crucial to rationally design technologies. Despite much research, a quantitative theoretical framework for detachment force remains elusive. In response, we interrogated the elemental droplet–surface system via comprehensive laboratory and computational experiments. The results reveal that the Young–Laplace equation can be utilized to accurately predict the droplet detachment force. When challenged against experiments with liquids of varying properties and droplet sizes, detaching from smooth and microtextured surfaces of wetting and non-wetting chemical make-ups, the predictions were in an excellent quantitative agreement. This study advances the current understanding of droplet physics and will contribute to the rational development of technologies. Understanding the physics that govern the dynamics of liquid droplets and their interaction with solid surfaces is crucial for a range of industrial applications, from pesticides to solar cells. Here, the authors develop a framework based on the Young-Laplace equation, to predict the force required to detach a drop from flat and microstructured solid surfaces. [ABSTRACT FROM AUTHOR]

Autophagy has emerged as a key regulator of cell metabolism. Recently, we have demonstrated that autophagy is involved in RNA metabolism by regulating ribosomal RNA (rRNA) synthesis. We found that autophagy-deficient cells display much higher 47S precursor rRNA level, which is caused by the accumulation of SQSTM1/p62 (sequestosome 1) but not other autophagy receptors. Mechanistically, SQSTM1 accumulation potentiates the activation of MTOR (mechanistic target of rapamycin kinase) complex 1 (MTORC1) signaling, which facilitates the assembly of RNA polymerase I pre-initiation complex at ribosomal DNA (rDNA) promoter regions and leads to the activation of rDNA transcription. Finally, we showed that SQSTM1 accumulation is responsible for the increase in protein synthesis, cell growth and cell proliferation in autophagy-deficient cells. Taken together, our findings reveal a regulatory role of autophagy and autophagy receptor SQSTM1 in rRNA synthesis and may provide novel mechanisms for the hyperactivated rDNA transcription in autophagy-related human diseases. Abbreviations: 5-FUrd: 5-fluorouridine; LAP: MAP1LC3/LC3-associated phagocytosis; MAP1LC3/LC3: microtubule associated protein 1 light chain 3; MTOR: mechanistic target of rapamycin kinase; PIC: pre-initiation complex; POLR1: RNA polymerase I; POLR1A: RNA polymerase I subunit A; rDNA: ribosomal DNA; RRN3: RRN3 homolog, RNA polymerase I transcription factor; rRNA: ribosomal RNA; SQSTM1/p62: sequestosome 1; TP53INP2: tumor protein p53 inducible nuclear protein 2; UBTF: upstream binding transcription factor. [ABSTRACT FROM AUTHOR]

[Display omitted] • SiO 2 @polymer nanoparticles with different surface charges are prepared for drilling fluid loss reduction. • Electrostatic forces between SiO 2 @polymer and bentonite play the decisive role in reducing fluid loss. • Electrostatic repulsion induces slow formation of thin and compact filter cake. • Electrostatic attraction induces fast formation of thick and loose filter cake. To elucidate the effects of filtration reducers' surface charge on drilling fluid filtration performance, three kinds of SiO 2 @polymer nanoparticles with different surface charges are prepared. When these nanoparticles are added into bentonite-based drilling fluids as filtration reducers, the negatively charged nanoparticles show the best filtration reduction performance while the positively charged nanoparticles show the most inferior filtration reduction performance. Moreover, more negative charges induce better filtration reduction performance. Conversely, more positive charges induce more inferior filtration reduction performance. The filtration performance of drilling fluids is decided by the compactness of the filter cake. And the interactions among the particles in the drilling fluids play an important role in affecting the compactness of filter cake. The electrostatic attraction forces between the positively charged nanoparticles and negatively charged bentonite particles promoted the aggregation before the formation of incompact filter cake, and the electrostatic repulsion forces between the negatively charged nanoparticles and negatively charged bentonite particles slowed down the aggregation of particles to form more compact filter cakes. These findings demonstrate the decisive role of surface charge of filtration reducers, which could provide guidance for searching suitable filtration controlling additives for drilling fluids in the future. [ABSTRACT FROM AUTHOR]

TIGIT is an emerging novel checkpoint target that is expressed on both tumor-infiltrating T cells and NK cells. Some current investigational antibodies targeting TIGIT have also achieved dramatic antitumor efficacy in late clinical research. Most recently, the relevance of NK cell–associated TIGIT signaling pathway to tumors' evasion of the immune system has been clearly revealed, which endows NK cells with a pivotal role in the therapeutic effects of TIGIT blockade. In this article, we describe a novel anti-TIGIT monoclonal antibody, AET2010, which was acquired from a phage-displayed human single-chain antibody library through a cell panning strategy. With emphasis on its regulation of NK cells, we confirmed the excellent ex vivo and in vivo antitumor immunity of AET2010 mediated by the NK-92MI cells. Intriguingly, our work also revealed that AET2010 displays a lower affinity but parallel avidity and activity relative to MK7684, an investigational monoclonal antibody from MSD, implying a reasonable balance of potency and potential side effects for AET2010. Together, these results are promising and warrant further development of AET2010. • We applied a cell panning strategy to select therapeutic antibodies from a phage-displayed human antibody library. • We identified a novel candidate therapeutic antibody with a low risk of potential side effects but undiminished efficacy. • The novel anti-TIGIT antibody exhibited excellent ex vivo and in vivo antitumor immunity mediated by NK-92MI cells. • This is the first report assessing the activity of TIGIT antibodies in a xenograft model with adoptive injection of NK-92MI. [ABSTRACT FROM AUTHOR]

In this paper, we study an on-line scheduling problem that is motivated by applications such as carpooling. The ride requests arrive on-line over-list and specify the service locations (among m locations). The goal is to determine a schedule that maximizes the number of satisfied requests using k servers. We consider two variants of the problem with respect to constraints on the service location: in the monotone service direction variant, the service locations of the requests assigned to a server must be monotonic; in the strict monotone service direction variant, the service locations must be strictly monotonic. We present lower bounds on the competitive ratio for both variants. For the monotone service direction variant, we give an optimal straightforward algorithm if k ≥ m and we prove that no deterministic on-line algorithm can achieve a constant competitive ratio if k < m. For the strict monotone service direction variant, we give a lower bound max ⁡ { 2 (m − 1) m , 1 } on the competitive ratio of barely deterministic algorithms if k > 2 , and a lower bound of max ⁡ { m 2 , 1 } if k ≤ 2. We propose a Balanced Interval Algorithm for the strict monotone service direction variant if k > 2 and report some numerical experiments to evaluate the efficiency of this algorithm. • We introduce two on-line algorithm problems with monotone service direction constraints which are applied for carpooling system. • We discuss the lower bounds and upper bounds of these two problems. • We propose a balanced interval algorithm and measure the algorithm performance with numerical experiments. [ABSTRACT FROM AUTHOR]

The tumor protein p53‐inducible nuclear protein 2 (TP53INP2) has been reported to participate in autophagy by interacting with autophagosome‐localized autophagy‐related protein 8 (Atg8) family proteins, including LC3. Here, we uncover a novel function for TP53INP2 in the autophagic degradation of proteins. We identify the ubiquitin‐interacting motif (UIM) of TP53INP2 that mediates its binding to ubiquitin and ubiquitinated proteins. TP53INP2 lacking the UIM is able to displace autophagic adaptor p62 from LC3, which leads to accumulation of ubiquitinated proteins in cells. Furthermore, overexpression of TP53INP2 lacking the UIM sensitizes cells to chloroquine treatment. Our findings indicate that TP53INP2 may act as a novel autophagic adaptor through recruiting ubquitinated substrates to autophagosomes for degradation. [ABSTRACT FROM AUTHOR]

Water renewal through the Bohai Strait largely dominates the water quality of the semi-enclosed Bohai Sea (BS), which connects only to the northern Yellow Sea (NYS) through the strait. Although the peak water transport through the Bohai Strait occurs in summer, the spatially averaged water residence time of the BS shows no significant decrease compared to other periods. A three-dimensional model is applied to unravel the detailed structure and dynamic processes of the summertime NYS water transport from the northern Laotieshan Channel to the BS interior. Model results from both climatological and hindcasting cases show that despite a large amount of the NYS water enters the strait, they are confined to the Laotieshan Channel between the Central Bank and Dalian surrounded by a strong Ω-shaped tidal front and could not move further north into the Liaodong Bay. The strong along-front flow steered by the topography forms a counter-clockwise circulation pattern in the strait zone, resulting in most of water southward movement east of the Central Bank, then join the outflow south of the strait and leave for the NYS. The Central Bank and the topographic sill north of the Laotieshan Channel act as a barrier that significantly reduces the water exchange between the strait zone and the BS interior, in particular the Liaodong Bay. Particle-tracking experiments suggest that less than 10% of particles released in the NYS could finally reach the BS interior, and among of them only a small portion of them could move further north into the Liaodong Bay. Momentum diagnostics suggest that the water transport northwest of the strait is dominated by geostrophic balance in the Ω-shaped frontal region. Sensitivity experiments indicate that tides promote the surface water transport from the NYS to the BS interior. The realistic wind forcing including synoptic events may facilitate the water transport from the strait to the BS interior by modulating the barotropic and baroclinic pressure gradient than that with the climatological wind case. [ABSTRACT FROM AUTHOR]

Given a set of n points, which is a unit set of m colored sets, we study the minimum circle to cover one of each colored set at least. In this paper, we study some problems of optimizing some properties of color-spanning set. Firstly, we show a way to find a color-spanning set for each point and constitute a union of color-spanning sets without FCVD (The Farthest Color Voronoi Diagram). The approach to find each color-spanning set is based on the nearest neighbor points which have different colors. For every color-spanning set, we can find a enclosing circle to cover all points of each color-spanning set, which is a good approximate for MDCS (The Minimum Diameter Color-Spanning Set) problem. We propose an approximation algorithm for the SECSC (The Smallest Color-Spanning Circle) problem with 2-factor approximation result. For | P | = n and | Q | = m , the worst running time of our algorithm is O ( n 2 ) . Although these results are not as good as previous results with FCVD, the performance of our algorithms in R d is much better than others. Moreover, an approximation algorithm can solve problem of minimum perimeter of the color-spanning set faster with time of O ( n 2 + n m log ⁡ n ) and ratio 6 . This result improved the ratio with only a little cost of time complexity. At last, we give an example for the 2-center SECSC problem. A fast computation of 2-center enclosing circle is proposed with time of O ( n 2 ) , but the ratio depends on the gap between the nearest distinct colored distance. [ABSTRACT FROM AUTHOR]

In this paper, we consider the online hierarchical scheduling problem on two parallel machines, with the objective of maximizing the minimum machine load. Since no competitive algorithm exists for this problem, we consider the semi-online version with bounded processing times, in which the processing times are bounded by an interval [ 1 , α ] where α ≥ 1 . We prove that no algorithm can have a competitive ratio less than 1 + α and present an optimal algorithm. Moreover, if we further know the sum of jobs' processing times in advance, we prove that no algorithm can have a competitive ratio less than α where 1 ≤ α < 2 , and propose an α -competitive algorithm for this case. [ABSTRACT FROM AUTHOR]

Summary Shuttling of macromolecules between different cellular compartments helps regulate the timing and extent of different cellular activities. Here, we report that LC3, a key initiator of autophagy that cycles between the nucleus and cytoplasm, becomes selectively activated in the nucleus during starvation through deacetylation by the nuclear deacetylase Sirt1. Deacetylation of LC3 at K49 and K51 by Sirt1 allows LC3 to interact with the nuclear protein DOR and return to the cytoplasm with DOR, where it is able to bind Atg7 and other autophagy factors and undergo phosphatidylethanolamine conjugation to preautophagic membranes. The association of deacetylated LC3 with autophagic factors shifts LC3’s distribution from the nucleus toward the cytoplasm. Thus, an acetylation-deacetylation cycle ensures that LC3 effectively redistributes in an activated form from nucleus to cytoplasm, where it plays a central role in autophagy to enable the cell to cope with the lack of external nutrients. [ABSTRACT FROM AUTHOR]

Abstract: In this paper, we consider two semi-online scheduling problems of parallel machines with two GoS (grade of service) levels and unit processing time, in which the objective is to minimize the makespan. Assume that the GoS levels of the first s machines are 2 and that of the last machines are 1 where m is the number of machines. The first problem is the lookahead version where an online algorithm is able to foresee the information of the next k jobs. The second problem is the buffer version where a buffer is available for storing at most g jobs. For the both versions, we prove that the lookahead ability or the buffer is useless for designing algorithm when or . We also show that no online algorithm has a competitive ratio less than for any constant k or g. Moreover, we present two optimal online algorithms for and . At last, for the case with only two machines, we prove that the two algorithms can get their best possible competitive ratio when and . [Copyright &y& Elsevier]

Abstract: In the problem of online time series search introduced by El-Yaniv et al. (2001) , a player observes prices one by one over time and shall select exactly one of the prices on its arrival without the knowledge of future prices, aiming to maximize the selected price. In this paper, we extend the problem by introducing profit function. Considering two cases where the search duration is either known or unknown beforehand, we propose two optimal deterministic algorithms respectively. The models and results in this paper generalize those of El-Yaniv et al. (2001) . [Copyright &y& Elsevier]

Abstract: We consider online scheduling problems to minimize modified total tardiness. The problems are online in the sense that jobs arrive over time. For each job , its processing time , due date and weight become known at its arrival time (or release time) . Preemption is not allowed. We first show that there is no finite competitive ratio for problem . So we focus on problem and show that D-SWPT (Delayed Shortest Weighted Processing Time) algorithm is -competitive. We further study two problems and , where and denote resumable and non-resumable models respectively, and denotes a non-available time interval with and . We give a lower bound of for both problems and prove that (Modified D-SWPT) is and -competitive in the resumable and non-resumable models, respectively. Moreover, we extend the upper bounds to the scenario of parallel machine scheduling with uniform job weight and an assumption that all machines have the same non-available time interval . A lower bound of is given as well for the scenario. [Copyright &y& Elsevier]

Abstract: We consider two problems of online scheduling on two uniform machines: online scheduling under a grade of service (GoS) and online scheduling with reassignment. These problems are online in the sense that when a job presents, we have to irrevocably assign it to one of the machines before the next job is seen. The objective is to minimize the makespan. In the first problem, GoS means that some jobs have to be processed by some machine so that they can be guaranteed a higher quality. Assume that the speed of the higher GoS machine is normalized to 1, while the speed of the other one is . We show that a lower bound of competitive ratio is in the case and in the case . Then we propose and analyze two online algorithms: HSF algorithm and EX-ONLINE algorithm. HSF is optimal in the case where and , where and denote the total processing time of jobs which request higher GoS machine and the total processing time of jobs which request the normal one, respectively. EX-ONLINE is optimal in the case . In the second problem, we study two subproblems and proposed in [Z. Tan, S. Yu, Online scheduling with reassignment, Operations Research Letters 36 (2008) 250–254]. Assume that the speeds of 2 uniform machines are 1 and , respectively. For where we can reassign the last jobs of the sequence, we show a lower bound of competitive ratio . For where we can reassign arbitrary jobs, we show a lower bound of competitive ratio . We propose a -competitive algorithm HSF-1 for both and . For , we propose a -competitive algorithm EX-RA, which is superior to HSF-1 when . [Copyright &y& Elsevier]

Abstract: In multiperson decision making situations, it is quite natural that different decision makers who may have different background and knowledge will provide their preferences by different kinds of preference relations. This paper proposes a linguistic multiperson decision making model (LMDMM) based on linguistic preference relations, integrating fuzzy preference relations, different types of multiplicative preference relations and multigranular linguistic preference relations. In the LMDMM, several transformation functions are first obtained to relate fuzzy preference relations and different types of multiplicative preference relations with multigranular linguistic preference relations. Then, we design the selection process of the LMDMM, based on the use of the fuzzy majority and the extended ordered weighted averaging operator (or the 2-tuple ordered weighted averaging operator), and discuss conditions under which the proposed selection process satisfies the social choice axioms. At last, we analyze the internal consistency of the proposed transformation functions. The results in this paper are helpful to complete Chiclana et al.''s fuzzy decision model [Integrating three representation models in fuzzy multipurpose decision making based on fuzzy preference relations, Fuzzy Sets and Systems 97 (1998) 33–48]. [Copyright &y& Elsevier]

Abstract: For a given convex polygon with inner angle no less than and boundary edge bounded by for , where is a given standard bar’s length, we investigate the problem of triangulating the polygon using some Steiner points such that (i) the length of each edge in triangulation is bounded by , where is a given constant and meets , and (ii) the number of non-standard bars in the triangulation is minimum. This problem is motivated by practical applications and has not been studied previously. In this paper, we present a heuristic to solve the above problem, which is based on the heuristic to generate a triangular mesh with less number of non-standard bars and shorter maximal edge length, and a process to make the length of each edge lower bounded. Our procedure is simple and easily implemented for this problem, and we prove that it has good performance guaranteed. [Copyright &y& Elsevier]

Abstract: In this paper, we study the performance of Saitou and Nei''s neighbor-joining method for phylogenetic reconstruction. We show that the edge radius of the method is . This improves an result by Atteson [The performance of neighbor-joining methods of phylogenetic reconstruction, Algorithmica 25 (1999) 251–278] and Xu et al. [A lower bound on the edge radius of Saitou and Nei''s method for phylogenetic reconstruction, Inform. Process. Lett. 94(5) (2005) 225–230]. Previously, only an upper bound and a lower bound were known. [Copyright &y& Elsevier]

In this paper, some results concerning the k-truck problem are produced. Firstly, the algorithms and their complexity concerning the off-line k-truck problem are discussed. Following that, a lower bound of competitive ratio (1+θ)·k/(θ·k+2) for the on-line k-truck problem is given, where θ is the ratio of cost of the loaded truck and the empty truck on the same distance, and a relevant lower bound for the on-line k-taxi problem followed naturally. Thirdly, based on the Position Maintaining Strategy (PMS), some new results which are slightly better than those of [11] for general cases are obtained. For example, a c-competitive or (c/θ+1/θ+1)-competitive algorithm for the on-line k-truck problem depending on the value of θ, where c is the competitive ratio of some algorithm to a relevant k-server problem, is developed. The Partial-Greedy Algorithm (PG) is used as well to solve this problem on a line with n nodes and is proved to be a (1+(n-k)/θ)-competitive algorithm for this case. Finally, the concepts of the on-line k-truck problem are extended to obtain a new variant: Deeper On-line k-Truck Problem (DTP). We claim that results of PMS for the STP (Standard Truck Problem) hold for the DTP. [ABSTRACT FROM AUTHOR]

Simple Summary: To investigate the genetic reprogramming that drives intestinal epithelial cells (IECs) maturation along the crypt-villus axis, entCerocytes were sequentially isolated from the villus tip to the crypts of porcine small intestine. The present study obtained the intestinal upper villus epithelial cells (F1) and crypt epithelial cells (F3) of 21-day suckling piglets using the divalent chelation and precipitation technique. By mRNA high-throughput sequencing analysis of F1 and F3, it was shown that a total of 672 unigenes were differentially expressed between F1 and F3, including 224 highly expressed and 448 minimally expressed unigenes. The greatest number of differentially expressed genes enriched in signal transduction, e.g., Wnt, Hippo, TGF-beta, mTOR, PI3K-Akt, and MAPK signaling pathways, were closely related to the differentiation, proliferation, maturation and apoptosis of IECs. Our results provide important information for identifying new regulators of IECs differentiation and maturation. Moreover, they can also provide insights into the regulatory mechanisms underlying intestinal epithelial cell renewal and the rapid repair of intestinal mucosal oxidative damage. It is well known that the small intestinal epithelial cells of mammals rapidly undergo differentiation, maturation, and apoptosis. However, few studies have defined the physiological state and gene expression changes of enterocytes along the crypt-villus axis in suckling piglets. In the present study, we obtained the intestinal upper villus epithelial cells (F1) and crypt epithelial cells (F3) of 21-day suckling piglets using the divalent chelation and precipitation technique. The activities of alkaline phosphatase, sucrase, and lactase of F1 were significantly higher (p < 0.05) than those of F3. To explore the differences at the gene transcription level, we compared the global transcriptional profiles of F1 and F3 using RNA-seq analysis technology. A total of 672 differentially expressed genes (DEGs) were identified between F1 and F3, including 224 highly expressed and 448 minimally expressed unigenes. Functional analyses indicated that some DEGs were involved in the transcriptional regulation of nutrient transportation (SLC15A1, SLC5A1, and SLC3A1), cell differentiation (LGR5, HOXA5 and KLF4), cell proliferation (PLK2 and TGFB3), transcriptional regulation (JUN, FOS and ATF3), and signaling transduction (WNT10B and BMP1), suggesting that these genes were related to intestinal epithelial cell maturation and cell renewal. Gene Ontology (GO) enrichment analysis showed that the DEGs were mainly associated with binding, catalytic activity, enzyme regulator activity, and molecular transducer activity. Furthermore, KEGG pathway analysis revealed that the DGEs were categorized into 284 significantly enriched pathways. The greatest number of DEGs enriched in signal transduction, some of which (Wnt, Hippo, TGF-beta, mTOR, PI3K-Akt, and MAPK signaling pathways) were closely related to the differentiation, proliferation, maturation and apoptosis of intestinal epithelial cells. We validated the expression levels of eight DEGs in F1 and F3 using qRT-PCR. The present study revealed temporal and regional changes in mRNA expression between F1 and F3 of suckling piglets, which provides insights into the regulatory mechanisms underlying intestinal epithelial cell renewal and the rapid repair of intestinal mucosal damage. [ABSTRACT FROM AUTHOR]

We study an online scheduling problem that is motivated by applications such as car-sharing. Users submit ride requests, and the scheduler aims to accept requests of maximum total profit using a single server (car). Each ride request specifies the pick-up time and the pick-up location (among two locations, with the other location being the destination). The scheduler has to decide whether or not to accept a request immediately at the time when the request is submitted (booking time). We consider two variants of the problem with respect to constraints on the booking time: In the fixed booking time variant, a request must be submitted a fixed amount of time before the pick-up time. In the variable booking time variant, a request can be submitted at any time during a certain time interval that precedes the pick-up time. We present lower bounds on the competitive ratio of deterministic and randomized algorithms for both variants and propose a greedy algorithm that achieves the best possible competitive ratio among deterministic algorithms. [ABSTRACT FROM AUTHOR]

Atrazine is a widely-applied herbicide used primarily to control weeds, which can persist in the ecosystem and exert potential toxicity to phytoplankton in the aquatic environment. In this study, acute toxicity of atrazine on microalgae Chlorella sp. was investigated with different initial cell densities (1 × 105 and 1 × 106 cells mL−1) and exposure periods (4 d and 8 d). Both growth rate and photosynthetic parameters of the microalgae in response of atrazine stress were determined to find out the sensitive indices and toxicological mechanisms. Because of the independence of initial cell density as well as the high sensitivity and reliability, the performance index PI ABS was verified as the most convincing photosynthetic parameter for indicating IC 50 of atrazine on Chlorella sp., being superior to the traditional parameters of growth rate and F V / F M. The IP amplitude (Δ F IP , fluorescence amplitude of the I-to-P-rise in the OJIP curve) was another sensitive biomarker to reflect atrazine stress. Results from chlorophyll fluorescence transient revealed that atrazine damaged the photosystem II (PS II) reaction center, suppressed the electron transport at the donor and receptor sides, and acted on the absorption, transfer, and utilization of light energy. Our results provide confirmatory references for understanding the toxicity and mechanisms of atrazine on freshwater microalgae. Image 1081 • Atrazine IC 50 was calculated and compared with different photosynthetic indices. • IC 50 assessed by PI ABS is the most sensitive indicator for atrazine toxicity. • The variation of PI ABS was independent of cell number (i.e. biomass). • Δ F IP was sensitive to reflect the atrazine stress. • Atrazine toxicity lies in obstruction of light absorption and electron transfer. [ABSTRACT FROM AUTHOR]

Paclitaxel-induced peripheral neuropathic pain (PIPNP) is a major therapy- and dose-limiting side effect that is extremely laborious to treat. Resveratrol (Res), with a structure name of 3,5,40-trihydroxystilbene, is a kind of natural polyphenolic chemical with plenty of useful characteristics such as anti-inflammatory, and anti-oxidative stress. However, the impact of Res on PIPNP remains unclear. Therefore, the current study intends to examine the analgesic effect of Res on PIPNP. In the present study, the results revealed that Res could effectively prevent the development of paclitaxel-induced PIPNP in a dose-dependent manner when repeated doses of Res were given during PIPNP induction. This prophylactic effect of Res was involved in inhibited paclitaxel-induced up-regulation of TRPV1 instead of TRPA1 in the dorsal root ganglia. Furthermore, the inhibition of TRPV1 up-regulation by Res may be involved in a phosphorylation of ERK mechanism. In summary, we conclude that Res plays an intriguing role in the prevention of PIPNP and thus may work as a therapeutic compound for treating and preventing PIPNP. [ABSTRACT FROM AUTHOR]

Based on the classical MapReduce concept, we propose an extended MapReduce scheduling model. In the extended MapReduce scheduling problem, we assumed that each job contains an open-map task (the map task can be divided into multiple unparallel operations) and series-reduce tasks (each reduce task consists of only one operation). Different from the classical MapReduce scheduling problem, we also assume that all the operations cannot be processed in parallel, and the machine settings are unrelated machines. For solving the extended MapReduce scheduling problem, we establish a mixed-integer programming model with the minimum makespan as the objective function. We then propose a genetic algorithm, a simulated annealing algorithm, and an L-F algorithm to solve this problem. Numerical experiments show that L-F algorithm has better performance in solving this problem. [ABSTRACT FROM AUTHOR]

In modern manufacturing industries, one production planning decision is generally impacted by not only limited processing capability but also uncertain processing environment together with carbon emission constraint. Therefore it is hard to meet all the customers’ demands by one manufacturer in a given production planning period. Motivated by these facts in the shared manufacturing era, this work investigates the problem of single machine scheduling with uncertain processing times of jobs, where job rejection and outsourcing options are both allowed. For the objective of maximizing the expected total profit, i.e., the revenue of completed jobs minus total costs together with penalties induced by outsourcing, delays, breach of contract and job rejections, a two-stage stochastic mixed-integer program is established. Two unsupervised machine learning methods, i.e., K-means and K-medoids, are integrated into the Sample Average Approximation (SAA) approach to improve the problem-solving efficiency. Two machine learning approaches based on the above two unsupervised machine learning methods are further adopted to cope with each realization of uncertain parameters. Numerical results demonstrate the effectiveness of the proposed methods. [ABSTRACT FROM AUTHOR]

Letting P be a set of n points in the plane, the discrete minimax 2-center problem (D M M 2 C P) is to find two disks centered at { p 1 , p 2 } ∈ P that minimize the maximum of two terms, namely, the Euclidean distance between two centers and the distance of any other point to the closer center. The mixed minimax 2-center problem (M M M 2 C P) is when one of the two centers is not in P. We present algorithms solving the D M M 2 C P and M M M 2 C P. The time complexities of solving the D M M 2 C P and M M M 2 C P are O (n 2 log ⁡ n) and O (n 2 log 2 ⁡ n) respectively. Furthermore, we consider two Steiner minimum sum dipolar spanning tree problems, in which one of the two dipoles is a Steiner point and the dipoles are both Steiner points. These two problems are shown to be solvable in O (n log ⁡ n) and O (n) time respectively. [ABSTRACT FROM AUTHOR]

Aryl methyl thioethers (III)/(VI) and methylene-bridged arylamines (IV)/(VII) are synthesized via highly regioselective para-methylthiolation/bridging methylenation of arylamines (I) and (V) using DMSO as the methylthio or methylene source. [ABSTRACT FROM AUTHOR]

Both electron-rich and electron-deficient substrates can be used and various functional groups are tolerated. [ABSTRACT FROM AUTHOR]

The factors of industry environment risks to enterprise financial activities are considered; seven kinds of industry environment risks influencing enterprise financial activities are chosen as state variables. The eighth paper is "Nonlinear Effect Analysis of Electricity Price on Household Electricity Consumption" by Zhang and Wen; they investigated the scenario effect of per capita income and regional differences in urbanization development on the relationship between electricity sales price and urban household electricity consumption. Accurate energy forecasting is essential to achieve greater efficiency and reliability in power system operation and security, energy pricing problems, and scheduling and planning of energy supply systems, among other areas. [Extracted from the article]

In group decision making (GDM) situations, it is quite natural that the decision makers who may have different background and knowledge will provide their preferences by means of different linguistic term sets. Specifically, multi-granular linguistic term sets that are not uniformly and symmetrically distributed will be employed. To deal with this type of GDM problems, this paper proposes a consensus-based GDM model by using two existing 2-tuple linguistic representation models (i.e., the Herrera and Martínez model and the Wang and Hao model), which we called the GDM model based on multi-granular unbalanced 2-tuple linguistic preference relations. First, the framework of the GDM model with multi-granular unbalanced 2-tuple linguistic preference relations is proposed. Then, the transformation function is obtained to relate multi-granular unbalanced linguistic preference relations with uniform balanced linguistic preference relations. Further, a consensus model is presented to help the decision makers reach a consensus. This consensus model not only provides a new way to simultaneously manage individual consistency and group consensus in a linear programming model, but also minimizes information loss (or consensus cost) when reaching the established consensus level. Finally, an example is given to illustrate the feasibility and validity of the proposed model. [ABSTRACT FROM AUTHOR]

Abstract: In this paper, we propose the concept of distribution assessments in a linguistic term set, and study the operational laws of linguistic distribution assessments. The weighted averaging operator and the ordered weighted averaging operator for linguistic distribution assessments are presented. We also develop the concept of distribution linguistic preference relations, whose elements are linguistic distribution assessments. Further, we study the consistency and consensus measures for group decision making based on distribution linguistic preference relations. Two desirable properties of the proposed measures are shown. A consensus model also has been developed to help decision makers improve the consensus level among distribution linguistic preference relations. Finally, illustrative numerical examples are given. The results in this paper provide a theoretic basis for the application of linguistic distribution assessments in group decision making. [Copyright &y& Elsevier]

By using the 2-tuple fuzzy linguistic representation model and by proposing the concept of the individual consistency evaluations, this paper develops a 2-tuple linguistic index to measure the consistency degree of linguistic preference relations. Comparing with the existing numerical consistency indexes, the proposed linguistic index not only measures the consistency degree of linguistic preference relations via a linguistic way, but also can reflect the individual difference on consistency degree of linguistic preference relations. Further, this paper proposes an algorithm to improving consistency degree in linguistic preference relations, and the proof of the convergence of this algorithm is also given. The results in this paper provide a theoretic basis for the application of consistent linguistic preference relations in decision making problems. [ABSTRACT FROM AUTHOR]

Abstract: The consistency measure is a vital basis for group decision making (GDM) based on fuzzy preference relations, and includes two subproblems: individual consistency and consensus consistency. This paper proposes linear optimization models for solving some issues on consistency of fuzzy preference relations, such as individual consistency construction, consensus model and management of incomplete fuzzy preference relations. Our proposal optimally preserves original preference information in constructing individual consistency and reaching consensus (in Manhattan distance sense), and maximizes the consistency level of fuzzy preference relations in calculating the missing values of incomplete fuzzy preference relations. Linear optimization models can be solved in very little computational time using readily available softwares. Therefore, the results in this paper are also of simplicity and convenience for the application of consistent fuzzy preference relations in GDM problems. [Copyright &y& Elsevier]

In group decision making, consensus models are decision aid tools and help experts modify their individual opinions to reach a closer agreement. Based on the concept of minimum-cost consensus, this paper proposes a novel framework to achieve minimum-cost consensus under aggregation operators. Analytical results indicate that the proposed framework reduces to the consensus model of Ben-Arieh when the selected aggregation operator is the ordered weighted averaging (OWA) operator with weight vector (1/2, \ldots, 0, \ldots, 1/2)^T. Furthermore, this paper closely examines the minimum-cost consensus models with a linear cost function under the common aggregation operators (e.g., the weighted averaging operator and the OWA operator). Linear-programming-based approaches are also developed to solve these models. The results of this paper significantly contribute to efforts to develop the consensus model of Ben-Arieh [ABSTRACT FROM PUBLISHER]

Parametric search is a useful tool in geometric optimization. Invented by Nimrod Megiddo in 1983, it has been widely used in computational geometry. Unfortunately, this technique has rarely been used in the combinatorial optimization community in China. In this paper, we introduce parametric search via three new geometric optimization applications. [ABSTRACT FROM AUTHOR]

Abstract: We study two online problems on uniform machines with speeds . The problems are online in the sense that all jobs arrive over time. Each job’s characteristics, such as processing time and weight become known at its arrival time. For the first problem , we prove that R-LIST algorithm is -competitive. For the second problem , we show that WSPT-1 algorithm is -competitive if for . Then we study a special case where . We obtain that algorithm WSPT-1 is -competitive if . [Copyright &y& Elsevier]

Chiclana, Herrera and Herrera-Viedma studied conditions under which the reciprocity property is maintained in the aggregation of reciprocal fuzzy preference relations using the OWA operator guided by a relative linguistic quantifier. In this note, we focus on the reciprocity in the aggregation of fuzzy preference relations (that is, the additive reciprocity is not assumed) using the OWA operator. By defining a reciprocity index for measuring the non-reciprocity degree of fuzzy preference relations, we show that a sufficient (but not necessary) condition under which a “collective” fuzzy preference relation, obtained by aggregating a set of “individual” fuzzy preference relations using an OWA operator guided by a linguistic quantifier with parameter and , has a reciprocity index no greater than the largest of the corresponding “individual” reciprocity indexes. Our result is helpful to complete Chiclana et al.''s decision model [F. Chiclana, F. Herrera, E. Herrera-Viedma, Integrating three representation models in fuzzy multipurpose decision making based on fuzzy preference relations, Fuzzy Sets and Systems 97 (1998) 33–48]. [Copyright &y& Elsevier]

Given a set P of n points in the plane, the two-circle point-labeling problem consists of placing 2n uniform, non-intersecting, maximum-size open circles such that each point touches exactly two circles. It is known that this problem is NP-hard to approximate. In this paper we give a simple algorithm that improves the best previously known approximation factor from 4/(1 + √33) ≈ 0.5931 to 2/3. The main steps of our algorithm are as follows. We first compute the Voronoi diagram, then label each point optimally within its cell, compute the smallest label diameter over all points and finally shrink all labels to this size. We keep the O(n log n) time and O(n) space bounds of the previously best algorithm. [ABSTRACT FROM AUTHOR]

Operation management of automated storage and retrieval system (AS/RS) has a great impact on system performance and is a hot research topic. Most existing works for AS/RS operation management address determining storage and retrieval (S/R) machine sequence and minimizing its travel time. In the paper, we study a new bi-objective S/R machine sequencing problem with task release time and due date in a two-depot AS/RS. The objective is to minimize the total travel time of the S/R machine and the total tardiness simultaneously. For the problem, a new bi-objective mixed integer linear programming model is established. Based on problem property analysis, an exact ϵ -constraint method, a non-dominated sorting genetic algorithm II and a promising heuristic are devised for the problem. Especially, the computational results show the efficiency and effectiveness of the proposed algorithms. [ABSTRACT FROM AUTHOR]