Augment with Care: Enhancing Graph Contrastive Learning with Selective Spectrum Perturbation

In recent years, Graph Contrastive Learning (GCL) has shown remarkable effectiveness in learning representations on graphs. As a component of GCL, good augmentation views are supposed to be invariant to the important information while discarding the unimportant part. Existing augmentation views with perturbed graph structures are usually based on random topology corruption in the spatial domain; however, from perspectives of the spectral domain, this approach may be ineffective as it fails to pose tailored impacts on the information of different frequencies, thus weakening the agreement between the augmentation views. By a preliminary experiment, we show that the impacts caused by spatial random perturbation are approximately evenly distributed among frequency bands, which may harm the invariance of augmentations required by contrastive learning frameworks. To address this issue, we argue that the perturbation should be selectively posed on the information concerning different frequencies. In this paper, we propose GASSER which poses tailored perturbation on the specific frequencies of graph structures in spectral domain, and the edge perturbation is selectively guided by the spectral hints. As shown by extensive experiments and theoretical analysis, the augmentation views are adaptive and controllable, as well as heuristically fitting the homophily ratios and spectrum of graph structures

Conformally Anodizing Hierarchical Structure in a Deformed Tube towards Energy-saving Liquid Transportation

The creation of drag-reducing surfaces in deformed tubes is of vital importance to thermal management, energy, and environmental applications. However, it remains a great challenge to tailor the surface structure and wettability inside the deformed tubes of slim and complicated feature. Here, we describe an electrochemical anodization strategy to achieve uniform and superhydrophobic coating of TiO2 nanotube arrays throughout the inner surface in deformed/bend titanium tubes. Guided by a hybrid carbon fibre cathode, conformal electric field can be generated to adaptatively fit the complex geometries in the deformed tube, where the structural design with rigid insulating beads can self-stabilize the hybrid cathode at the coaxial position of the tube with the electrolyte flow. As a result, we obtain a superhydrophobic coating with a water contact angle of 157° and contact angle hysteresis of less than 10°. Substantial drag reduction can be realised with an overall reduction up to 25.8 % for the anodized U-shaped tube. Furthermore, we demonstrate to spatially coat tubes with complex geometries, to achieve energy-saving liquid transportation. This facile coating strategy has great implications in liquid transport processes with the user-friendly approach to engineer surface regardless of the deformation of tube/pipe

Heat-Shock Protein 90 Promotes Nuclear Transport of Herpes Simplex Virus 1 Capsid Protein by Interacting with Acetylated Tubulin

Although it is known that inhibitors of heat shock protein 90 (Hsp90) can inhibit herpes simplex virus type 1 (HSV-1) infection, the role of Hsp90 in HSV-1 entry and the antiviral mechanisms of Hsp90 inhibitors remain unclear. In this study, we found that Hsp90 inhibitors have potent antiviral activity against standard or drug-resistant HSV-1 strains and viral gene and protein synthesis are inhibited in an early phase. More detailed studies demonstrated that Hsp90 is upregulated by virus entry and it interacts with virus. Hsp90 knockdown by siRNA or treatment with Hsp90 inhibitors significantly inhibited the nuclear transport of viral capsid protein (ICP5) at the early stage of HSV-1 infection. In contrast, overexpression of Hsp90 restored the nuclear transport that was prevented by the Hsp90 inhibitors, suggesting that Hsp90 is required for nuclear transport of viral capsid protein. Furthermore, HSV-1 infection enhanced acetylation of α-tubulin and Hsp90 interacted with the acetylated α-tubulin, which is suppressed by Hsp90 inhibition. These results demonstrate that Hsp90, by interacting with acetylated α-tubulin, plays a crucial role in viral capsid protein nuclear transport and may provide novel insight into the role of Hsp90 in HSV-1 infection and offer a promising strategy to overcome drug-resistance

Are you a human or a humanoid: Predictive user modelling through behavioural analysis of online gameplay data

Intelligent agents are widely used in robotics, gaming and simulation. A key issue is modelling human behaviours so that intelligent agents can use a human’s behavioural model to imitate them and predict their next moves. In this article, we use Internet-based multiplayer online gaming (MOG) as a case study to present our approach to predictive user modelling through behavioural analysis of online gameplay data. As latency is an inherited bottleneck of the Internet and is likely to remain so into a foreseeable future, a lot of efforts have been made to address the resulting issues. Most of the existing latency handling techniques are based on the assumption that latency is within an acceptable threshold so that they can alleviate or even completely hide its negative impact on players’ quality of experience (QoE) that directly determines consumers’ satisfaction of the provided MOG services. While this assumption is mostly valid, it is worth noting that a player’s Internet connection latency always fluctuates (known as jitter), possibly to the extent of exceeding a MOG’s designated threshold in which case none of the techniques can handle properly but disconnecting the player from the gameplay session. Forcing a player to quit prematurely simply due to a spike of unusual high latency has a significant negative impact both on the gameplay’s fairness and on the player’s QoE. To improve customer satisfaction of a MOG service, we propose a more tolerant approach by temporarily substituting a player with a humanoid bot in the event of latency hikes so that the player always remains in the gameplay session. The challenge in this approach is to create a personalised humanoid bot that can imitate the playing pattern of the individual human player being substituted. Our solution is to first extract key variables that have impact on the human player’s decision-makings through behavioural analysis of the player’s historical gameplay data, then model the relationships among these variables, and finally creates the player’s humanoid bot with the model. In this paper, we use a multiplayer online pong game as a case study to explain behavioural variables, modelling techniques, processes, outcomes, and performance studies

Exploring market competition over topics in spatio-temporal document collections

With the prominence of location-based services and social networks in recent years, huge amounts of spatio-temporal document collections (e.g., geo-tagged tweets) have been generated. These data collections often imply user’s ideas on different products and thus are helpful for business owners to explore hot topics of their brands and the competition relation to other brands in different spatial regions during different periods. In this work, we aim to mine the topics and the market competition of different brands over each topic for a category of business (e.g., coffeehouses) from spatio-temporal documents within a user-specified region and time period. To support such spatio-temporal search online in an exploratory manner, we propose a novel framework equipped by (1) a generative model for mining topics and market competition, (2) an Octree-based off-line pre-training method for the model and (3) an efficient algorithm for combining pre-trained models to return the topics and market competition on each topic within a user-specified pair of region and time span. Extensive experiments show that our framework is able to improve the runtime by up to an order of magnitude compared with baselines while achieving similar model quality in terms of training log-likelihood.Agency for Science, Technology and Research (A*STAR)Ministry of Education (MOE)This work was supported in part by a MOE Tier-2 grant MOE2016-T2-1-137, a MOE Tier-1 grant RG31/17, and NSFC under the grant 61772537. It was also partially supported under the A*STAR TSRP fund 1424200021

3D Printing of Silicone Elastomers for Soft Actuators

A procedure for 3D printing of silicone elastomers with a direct ink writing (DIW) process has demonstrated great potential in areas as diverse as flexible electronics, medical devices, and soft robotics. In this report, we propose a comprehensive guide for printing highly stretchable silicones in response to material, equipment and process dilemmas. Specifically, we first tested the material properties of Dow Corning 737, then modeled and simulated two commonly used needles to select a suitable needle, followed by parameter optimization experiments using the built DIW printer to find out the appropriate printing speed and layer height with a defined air pressure and needle diameter. Finally, the optimal combination of parameters was obtained. For further demonstration, artificial muscles and structurally complex soft grippers were also printed directly to verify the feasibility of high-precision 3D printing of soft actuators with soft materials. We believe that this work could provide a guide for further work using the DIW process to print soft matter in a wide range of application scenarios

Selection of candidates for surgery as local therapy among early-stage small cell lung cancer patients: a population-based analysis

Abstract Background Surgery and radiotherapy are considered local therapies for small cell lung cancer (SCLC). The present study aimed to select candidates for surgery as local therapy among patients with stage I or II SCLC, based on the eighth edition of the TNM classification for lung cancer. Methods Patients diagnosed with SCLC between 2004 and 2013 were selected from the Surveillance, Epidemiology, And End Results database. The TNM stage of SCLC in these patients was re-classified according to the eighth edition of the TNM classification for lung cancer. Patients with stage I or II SCLC were included in the present study. Overall survival (OS) and lung cancer-specific survival (LCSS) were separately compared in the different TNM stages between patients who received surgery and radiotherapy as local therapy. Multivariate analysis was applied to evaluate multiple factors associated with survival. Results Among the 2129 patients included in the present study, 387 (18.2%) received surgery, 1032 (48.5%) underwent radiotherapy as local therapy, 154 (7.2%) underwent surgery and radiotherapy, and 556 (26.1%) did not undergo either surgery or radiotherapy. Among patients with T1-2N0 (tumor size ≤ 50 mm without positive lymph nodes) disease, patients who underwent surgery had higher 5-year OS and LCSS rates than patients who received radiotherapy (T1N0: 46.0% vs. 23.8%, P < 0.001, and 58.4% vs. 36.4%, P < 0.001, respectively; T2N0: 42.6% vs. 24.7%, P = 0.004, and 48.8% vs. 31.3%, P = 0.011, respectively). Multivariate analysis results revealed that surgery was associated with low risk of death. However, among T3N0 or T1-2N1 (stage IIB) SCLC patients, patients who underwent surgery did not have higher 5-year OS and LCSS rates than patients who received radiotherapy (T3N0: 16.2% vs. 26.5%, P = 0.085, and 28.7% vs. 30.9%, P = 0.372, respectively; T1-2N1: 20.3% vs. 29.0%, P = 0.146, and 25.6% vs. 35.5%, P = 0.064, respectively). Conclusions Based on the assumption that the overwhelming majority of stage I or II SCLC patients who underwent surgery or radiotherapy also received certain types of systemic therapy, only patients with T1-2N0 SCLC may benefit from surgery as local therapy. Patients with T3N0 or T1-2N1 SCLC may consider radiotherapy as local therapy

Numerical and experimental study of VM type pulse tube cryocooler with multi-bypass operating below 4 K

International audienceThe Vuilleumier (VM) type pulse tube cryocooler (VPTC) is a new kind of 4 K cryocooler which had been experimentally verified. This paper presents the recent advances on a 4 K VPTC in our laboratory. First, the mechanism of multi-bypass was numerically studied using Sage software. The results showed that the function of the multi-bypass is not only similar to a double-inlet, but also to an orifice, which makes the VPTC work like a two-stage cryocooler. Based on the simulation results, the performance of VPTC was experimentally studied. Under its optimal operating conditions, a no-load temperature of 3.7 K has been obtained, which is the first demonstration of a single-stage VPTC obtaining temperatures below 4 K. It can supply about 14mW cooling power at 4.2 K and about 100 mW cooling power at 35 K simultaneously, which has potential application as the pre-cooler for an adiabatic demagnetization refrigerator (ADR). Finally, based on this VPTC, a new mK cooling chain for HUBS (Hot Universe Baryon Surveyor) satellite is proposed and its prospect has also been theoretically analyzed

Predictive Value of Folate Receptor-Positive Circulating Tumor Cells for the Preoperative Diagnosis of Lymph Node Metastasis in Patients with Lung Adenocarcinoma

Noninvasive assessments of the risk of lymph node metastasis (LNM) in patients with lung adenocarcinoma (LAD) are of great value for selecting individualized treatment options. However, the diagnostic accuracies of different preoperative LN evaluation methods in routine clinical practice are not satisfactory. Here, an assessment to detect folate receptor (FR)-positive circulating tumor cells (CTCs) based on ligand-targeted enzyme-linked polymerization is established. FR-positive CTCs have the potential to improve the specificity and sensitivity of diagnosing LNM in lung cancer patients. The addition of CTC level improved the diagnostic efficiency of the initial prediction model that comprises other clinical parameters. A nomogram for predicting preoperative LNM is established, which showed good prediction and calibration capacities and achieved an average area under the curve of 0.786. Good correlations are observed between the CTC level and nodal classifications, such as the number of positive LNs and the ratio of the number of positive LNs to removed LNs (LN ratio or LNR). The ligand-targeted enzyme-linked polymerization-assisted assessment of CTCs enables noninvasive detection and has a useful predictive value for the preoperative diagnosis of LNM in patients with LAD