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Abstract spt23 plays multiple roles in the thermal tolerance of budding yeast. spt23 regulates unsaturated lipid acid (ULA) content in the cell, which can then significantly affect cellular thermal tolerance. Being a Ty suppressor, spt23 can also interact with transposons (Tys) that are contributors to yeast’s adaptive evolution. Nevertheless, few studies have investigated whether and how much spt23 can exert its regulatory functions through transposons. In this study, expression quantitative trait loci (eQTL) analysis was conducted with thermal-tolerant Saccharomyces cerevisiae strains, and spt23 was identified as one of the most important genes in mutants. spt23-overexpression (OE), deletion (Del), and integrative-expressed (IE) strains were constructed. Their heat tolerance, ethanol production, the expression level of key genes, and lipid acid contents in the cell membranes were measured. Furthermore, LTR (long terminal repeat)-amplicon sequencing was used to profile yeast transposon activities in the treatments. The results showed the Del type had a higher survival rate, biomass, and ethanol production, revealing negative correlations between spt23 expression levels and thermal tolerance. Total unsaturated lipid acid (TULA) contents in cell membranes were lower in the Del type, indicating its negative association with spt23 expression levels. The Del type resulted in the lower richness and higher evenness in LTR distributions, as well as higher transposon activities. The intersection of 3 gene sets and regression analysis revealed the relative weight of spt23’s direct and TY-induced influence is about 4:3. These results suggested a heat tolerance model in which spt23 increases cell thermal tolerance through transcriptional regulation in addition to spt23-transposon triggered unknown responses. Key points • spt23 is a key gene for heat tolerance, important for LA contents but not vital. • Deletion of spt23 decreases in yeast’s LTR richness but not in evenness. • The relative weight of spt23’s direct and TY-induced influence is about 4:3.

Water vapor condensation on superhydrophobic surfaces has received much attention in recent years because of its ability to shed water droplets via coalescence-induced droplet jumping. However, the efficient removal of jumping droplets can be limited by droplets return to the surface due to gravity, entrainment in bulk convective vapor flow, and entrainment in local condensing vapor flow. The return droplet merged with others and induced multi-hop jumping, whose mechanism still remains poorly understood. In this work, a VOF simulation is carried out to investigate the multi-hop jumping. If the returned droplets contact the droplets on the surface before touching the surface, the returned droplet coalesce with the droplets on the surface in the air, which is not conducive to shrinkage and rebounding, and the intrinsic multi-hop jumping process is inhibited. The momentum of the returned droplets is transformed into the momentum of the jumping droplets, and the multi-hop jumping process is strengthened. The multi-hop jumping velocity is linearly related to the velocity of the returned droplet. When the droplet radius ratio is less than 0.615, the momentum generated by the intrinsic multi-hop jumping can be neglected, and the multi-hop jumping velocity can be predicted base on the velocity of the returned droplet. This work will provide effective guidelines for the design of functional SHSs with enhanced droplet jumping for a wide range of industrial applications.

The direction control of self-propelled jumping of droplets has great significance for efficient chip cooling, anti-icing and self-cleaning. The transport mechanism of guided self-propelled jumping needs to be further explored since it is different in many ways from the extensively-studied vertical jumping of coalescing droplets on surfaces without a surface energy gradient. In this work, the VOF method was used to simulate the guided self-propelled jumping of droplets on superhydrophobic, wettability gradient surfaces. The effects of the surface energy gradient and the initial droplet arrangement on the jumping velocity and energy conversion efficiency are investigated. The results show that the jumping direction is tilted to the side with a smaller contact angle, rather than being perpendicular to the surface, due to the uneven force distribution along the three-phase line. In addition, the surface energy gradient reduces the droplet symmetry resulting in a lower energy conversion efficiency.

Hybridization is very common in flowering plants and it plays a significant role in plant evolution and adaptation. Melastoma L. (Melastomataceae) comprises about 80–90 species in tropical Asia and Oceania, among which 41 species occur in Borneo. Natural hybridization is frequently reported in Melastoma in China, but so far there have been no confirmed cases of hybridization in Southeast Asia (including Borneo), where most species occur. Here, we identified a case of natural hybridization between Melastoma malabathricum L. and Melastoma beccarianum Cogn. in Sarawak, Malaysia, by using sequence data of three nuclear genes and one chloroplast intergenic spacer. Melastoma malabathricum is the most widespread species of this genus, occurring in almost the whole range of this genus, while M. beccarianum is a local species endemic to northern Borneo. Our results showed that natural hybridization and introgression occur between M. malabathricum and M. beccarianum, and the introgression was asymmetrical, mainly from M. malabathricum to M. beccarianum. As adaptive traits can be transferred by introgression, our study suggests that natural hybridization should be a significant mechanism for the evolution and adaptation of Melastoma in Southeast Asia. However, introgression from the common species M. malabathricum to the relatively rare species M. beccarianum may cause the decline of M. beccarianum, incurring conservation concern. With a large number of species of Melastoma and almost year‐around flowering in Southeast Asia, more cases of natural hybridization are expected to be found and identified in near future.

Mbp1p is a component of MBF (MluI cell cycle box binding factor, Mbp1p-Swi6p) and is well known to regulate the G1–S transition of the cell cycle. However, few studies have provided clues regarding its role in fermentation. This work aimed to recognize the function of the MBP1 gene in ethanol fermentation in a wild-type industrial Saccharomyces cerevisiae strain. MBP1 deletion caused an obvious decrease in the final ethanol concentration under oxygen-limited (without agitation), but not under aerobic, conditions (130 rpm). Furthermore, the mbp1Δ strain showed 84% and 35% decreases in respiration intensity under aerobic and oxygen-limited conditions, respectively. These findings indicate that MBP1 plays an important role in responding to variations in oxygen content and is involved in the regulation of respiration and fermentation. Unexpectedly, mbp1Δ also showed pseudohyphal growth, in which cells elongated and remained connected in a multicellular arrangement on yeast extract-peptone-dextrose (YPD) plates. In addition, mbp1Δ showed an increase in cell volume, associated with a decrease in the fraction of budded cells. These results provide more detailed information about the function of MBP1 and suggest some clues to efficiently improve ethanol production by industrially engineered yeast strains. IMPORTANCE Saccharomyces cerevisiae is an especially favorable organism used for ethanol production. However, inhibitors and high osmolarity conferred by fermentation broth, and high concentrations of ethanol as fermentation runs to completion, affect cell growth and ethanol production. Therefore, yeast strains with high performance, such as rapid growth, high tolerance, and high ethanol productivity, are highly desirable. Great efforts have been made to improve their performance by evolutionary engineering, and industrial strains may be a better start than laboratory ones for industrial-scale ethanol production. The significance of our research is uncovering the function of MBP1 in ethanol fermentation in a wild-type industrial S. cerevisiae strain, which may provide clues to engineer better-performance yeast in producing ethanol. Furthermore, the results that lacking MBP1 caused pseudohyphal growth on YPD plates could shed light on the development of xylose-fermenting S. cerevisiae, as using xylose as the sole carbon source also caused pseudohyphal growth.

Entity matching (EM) refers to the problem of identifying tuple pairs in one or more relations that refer to the same real world entities. Supervised machine learning (ML) approaches, and deep learning based approaches in particular, typically achieve state-of-the-art matching results. However, these approaches require many labeled examples, in the form of matching and non-matching pairs, which are expensive and time-consuming to label. In this paper, we introduce Panda, a weakly supervised system specifically designed for EM. Panda uses the same labeling function abstraction as Snorkel, where labeling functions (LF) are user-provided programs that can generate large amounts of (somewhat noisy) labels quickly and cheaply, which can then be combined via a labeling model to generate accurate final predictions. To support users developing LFs for EM, Panda provides an integrated development environment (IDE) that lives in a modern browser architecture. Panda's IDE facilitates the development, debugging, and life-cycle management of LFs in the context of EM tasks, similar to how IDEs such as Visual Studio or Eclipse excel in general-purpose programming. Panda's IDE includes many novel features purpose-built for EM, such as smart data sampling, a builtin library of EM utility functions, automatically generated LFs, visual debugging of LFs, and finally, an EM-specific labeling model. We show in this demo that Panda IDE can greatly accelerate the development of high-quality EM solutions using weak supervision., Comment: video can be found at https://chu-data-lab.cc.gatech.edu/ml-for-data-integration/

Impacting between the multilayer Kelly bar and the power head has a detrimental effect on the drilling system and may cause huge losses to the construction engineering and machinery. This study is a further development of the vibro-impact mechanism, and especially, the study considers the constraint of the steel rope on the multilayer Kelly bar. Efficient analytical models are presented, and the total responses are obtained. Three types of displacement response are found by changing the matching relationship of global parameters. The first type has the optimal vibration control performance with the shortest path and no periodicity. The second type is inferior to the first type. The third type has the worst vibration-control performance with the longest path and periodicity. Then this article proposes the general feasibility to get the first type of displacement response and the most effective way is controlling the steel rope velocity. The research provides the foundation for the intelligent control of steel rope velocity on the rig machine.

Replacement of a novel candidate ethanol fermentation-associated regulatory gene

Computer game is an important research direction in the field of artificial intelligence. Among them, incomplete information poker games are relatively difficult to implement compared to the intelligent algorithm of chess games. Dou Dizhu game is a kind of incomplete information game poker game. This paper uses convolution neural network, through the analysis large number of game data, to obtain a better landlord identity card model. Experimental results show that the model can provide efficient and reasonable results in Dou Dizhu games, similar to poker played by humans.

Spt proteins are defined as a large family of transcription regulators of the yeast Saccharomyces cerevisiae. They are crucial components of the SAGA complex that regulates transcription through interaction with the TATA box in the upstream region of the target genes. About 10% of total gene transcriptions are related to Spt proteins and these genes are highly related to environmental stress response. Such vast regulation network and complex mechanisms have become a hotspot. Spt proteins are also important to suppress transposon-induced mutations, being a switch on regulation of transposon behaviors and adaptive evolution of Saccharomyces cerevisiae. Besides that, some Spt proteins are directly involved in regulating unsaturated lipid acids synthesis, which could remold the cell membrane to resist environmental stresses. Here, we review Spt proteins, the advances in Spt proteins study, and their potential applications in improving yeast's stress resistance through transcription regulation, transposon activity regulation and cell membrane alternation.Spt 是一大类参与酿酒酵母转录调控的蛋白质。Spt 蛋白是SAGA 复合体的组成部分，该复合体与基因上游TATA 框区域相互作用而发挥调控作用。根据目前的研究，约有10%的酿酒酵母基因转录受到Spt 蛋白的调控，且与环境压力下上调基因的调控密切相关。Spt 蛋白参与的庞大的调控网络及其复杂的调节机制是当前一个研究热点。Spt 蛋白还具有转座子抑制的功能，是转座子功能调控和适应性进化意义上的重要“开关”。除此之外，一些Spt 蛋白可以直接调控不饱和脂肪酸的合成，从而直接影响细胞膜重塑，对于酵母广泛抗性具有重要意义。文中从以上3 个维度对迄今为止Spt 蛋白的研究进展进行综述，结合前期研究工作，对于Spt 蛋白通过转录调控、细胞膜转变、转座活性调节用以增强酿酒酵母抗性的潜在作用谨作展望。.

As AlphaGo come into view, artificial intelligence for board games once again becomes the focus of the world, while the research for card games isn't deep enough. At present, the study of computer game algorithm of board games is more than in card games. One reason for this is the algorithms of card games are more difficult to implement than board games due to the imperfect information nature of the card games. We present a method that based on rules. We carry on research on card splitting, bidding, playing and following of Dou Dizhu. Experimental results show higher ratio of winning of our method than the method with simple strategies.

Most of hydraulic strand jacks cannot fulfill consecutive motion of lifting or lowering. Non-consecutive motion will generate additional inertial force that probably changes initial stress distribution of large and heavy structure in addition to be time-consuming. To solve the problem, an electrohydraulic system and corresponding strand jack were developed. The new strand jack uses two lifting cylinders to alternate lifting (lowering). The velocity difference between the two lifting cylinders is a key parameter to achieve smooth transferring-load and consecutive motion. The working principle of lifting is different from that of lowering. Electrohydraulic system is presented. To get the least values of velocity difference and the transferring-load stroke, the method of double-objective optimum is applied. Test results verify that the strand jack and electrohydraulic system can fulfill consecutive motion of lifting and lowering.

Part of the Central Ring Fast Autoroad in Shanghai, Beihong Vehicular Undercrossing Tunnel is a two-way, eight-lane vehicular tunnel of 126-m long, 34.2-m wide, and 7.85-m high. An electrohydraulic control system for synchronously jacked box tunneling was developed in the project. Estimation of jacking force is essential prerequisite of design of electrohydraulic system. Volume speed-regulating hydraulic circuit rather than throttle circuit was used to adjust flow rate, and the rotating speed of driving motor of main pump is controlled by variable voltage variable frequency (VVVF) technology. Three-level structure of control system was employed. A “double-object synchronization” control scheme enables 112 cylinders to coordinate the extending action, and automatically achieve synchronous motion and posture control of box and uniform load distribution to each pump unit. Differences are controlled within ± 40 mm during the whole jacking process.