KINEMATICS OF FOREHAND ATTACK ON ACCELERATED LOOP TECHNIQUES IN TABLE TENNIS - A CASE STUDY

INTRODUCTION: Although the fast forehand attack style of Chinese players has secured for them a leading position in the table tennis world, the accelerated loop technique still presents a problem in competition. However, some elite Chinese forehand attack players have contended very well with players using the accelerated loop technique. This demonstrates that the forehand attack is an effective technique with which to overcome the “loop”. From literature review, we found that cinematographical and electromyographical data on forehand attack on accelerated loop techniques was lacking. The purpose of this paper was to explore the technical characteristics of elite table tennis players performing forehand attack on accelerated loop techniques. In addition, the data collected for this study will provide biomechanical references for coaches and less experienced players

Channel sensing for holographic MIMO surfaces based on interference principle

The Holographic Multiple-Input and Multiple-Output (HMIMO) provides a new paradigm for building a more cost-effective wireless communication architecture. In this paper, we derive the principles of holographic interference theory for electromagnetic wave reception and transmission, whereby the optical holography is extended to communication holography and a channel sensing architecture for holographic MIMO surfaces is established. Unlike the traditional pilot-based MIMO channel estimation approaches, the proposed architecture circumvents the complicated processes like filtering, analog to digital conversion (ADC), down conversion. Instead, it relies on interfering the object waves with a pre-designed reference wave, and therefore reduces the hardware complexity and requires less time-frequency resources for channel estimation. To address the self-interference problem in the holographic recording process, we propose a phase shifting-based interference suppression (PSIS) method according to the structural characteristics of communication hologram and interference composition. We then propose a Prony-based multi-user channel segmentation (PMCS) algorithm to acquire the channel state information (CSI). Our theoretical analysis shows that the estimation error of the PMCS algorithm converges to zero when the number of HMIMO surface antennas is large enough. Simulation results show that under the holographic architecture, our proposed algorithm can accurately estimate the CSI in multi-user scenarios

Deciphering the role of RNA structure in translation efficiency.

BACKGROUND: RNA secondary structure has broad impact on the fate of RNA metabolism. The reduced stability of secondary structures near the translation initiation site/start codon of the coding region promotes the efficiency of translation in both prokaryotic and eukaryotic species. However, the inaccuracy of in silico folding and the focus on the coding region limit our understanding of the global relationship between the whole mRNA structure and translation efficiency. Leveraging high-throughput RNA structure probing data in the transcriptome, we aim to systematically investigate the role of RNA structure in regulating translation efficiency. RESULTS: Here, we analyze the influences of hundreds of sequence and structural features on translation efficiency in the mouse embryonic stem cells (mESCs) and zebrafish developmental stages. Our findings reveal that overall in vivo RNA structure has a higher relative importance in predicting translation efficiency than in vitro RNA structure in both mESCs and zebrafish. Also, RNA structures in 3\u27 untranslated region (UTR) have much stronger influence on translation efficiency compared to those in coding regions or 5\u27 UTR. Furthermore, strong alternation between in vitro and in vivo structures in 3\u27 UTR are detected in highly translated mRNAs in mESCs but not zebrafish. Instead, moderate alteration between in vitro and in vivo RNA structures in the 5\u27 UTR and proximal coding regions are detected in highly translated mRNAs in zebrafish. CONCLUSIONS: Our results suggest the openness of the 3\u27 UTR promotes the translation efficiency in both mice and zebrafish, with the in vivo structure in 3\u27 UTR more important in mice than in zebrafish. This reveals a novel role of RNA secondary structure on translational regulation

RIS-Aided Wireless Communications: Prototyping, Adaptive Beamforming, and Indoor/Outdoor Field Trials

The prospects of using a Reconfigurable Intelligent Surface (RIS) to aid wireless communication systems have recently received much attention from academia and industry. Most papers make theoretical studies based on elementary models, while the prototyping of RIS-aided wireless communication and real-world field trials are scarce. In this paper, we describe a new RIS prototype consisting of 1100 controllable elements working at 5.8 GHz band. We propose an efficient algorithm for configuring the RIS over the air by exploiting the geometrical array properties and a practical receiver-RIS feedback link. In our indoor test, where the transmitter and receiver are separated by a 30 cm thick concrete wall, our RIS prototype provides a 26 dB power gain compared to the baseline case where the RIS is replaced by a copper plate. A 27 dB power gain was observed in the short-distance outdoor measurement. We also carried out long-distance measurements and successfully transmitted a 32 Mbps data stream over 500 m. A 1080p video was live-streamed and it only played smoothly when the RIS was utilized. The power consumption of the RIS is around 1 W. Our paper is vivid proof that the RIS is a very promising technology for future wireless communications.Comment: 13 pages, 18 figures, submitte

Determination of vehicle requirements of AGV system based on discrete event simulation and response surface methodology

The determination of AGV vehicle requirements in a manufacturing system has a great impact on the system performance. This paper first defines the AGV vehicle requirement determination as a general optimization problem, and secondly develops a new AGV vehicle requirement determination method capable of effective solving the problem. This method features with the combination of discrete event simulation (DES), sensitivity analysis, fractional factorial design (FFD) and response surface methodology (RSM). Tests and comparisons with other simulation based methods have shown that the proposed method combining the simulation method with analytical method, can make full use of their respective advantages and overcome the defects of existing methods. It is more practical

Renal protective effect and mechanism research of hypoxia inducible factor-1α inhibitor YC-1 in diabetic nephropathy mice

Objective·To investigate the effect of hypoxia inducible factor-1α (HIF-1α) inhibitor YC-1 on the progression of diabetic nephropathy (DN) in mice and the potential mechanism.Methods·Ten-week-old male db/db mice (DN model) and their nondiabetic wild-type (WT) littermates were divided into 4 groups (n=6) according to whether treated with YC-1 or not: WT group, WT+YC-1 group, DB group, and DB+YC-1 group. The treatment groups were intraperitoneally injected with YC-1 (20 mg·kg-1) once a day, while the non-treatment groups received the same volumes of DMSO injection. After a total of 8 weeks of intervention, blood glucose, body weight, and kidney weight of all mice were measured. Serum, urine and kidney tissue samples were harvested. Serum creatinine, urinary albumin-to-creatinine ratio (UACR), and urine neutropil gelatinase-associated lipocalin (NGAL) levels were detected. The kidneys were stained with ‎hemat‎oxyli‎n-eosin (H-E) and periodic acid-Schiff (PAS) to observe the pathological changes. Masson staining was used to detect fibrosis, collagen-Ⅰ was detected by immunohistochemistry, and α-smooth muscle actin (α-SMA) was detected by Western blotting. The expression of HIF-1α was detected by both Western blotting and immunohistochemistry. TUNEL staining and Western blotting for apoptosis-related proteins were used to observe the cell apoptosis level. Superoxide dismutase (SOD) activity and malondialdehyde (MDA) level were detected by the kits. Endoplasmic reticulum stress (ERS) markers, including immunoglobulin heavy chain binding protein (BiP, also known as GRP78), phospho-protein kinase R-like endoplasmic reticulum kinase (p-PERK), total PERK, phospho-eukaryotic initiation factor 2α (p-eIF2α), total eIF2α, activating transcription factor 4 (ATF4), and C/EBP homologous protein (CHOP), were determined by Western blotting.Results·Compared with the WT group, the DB group showed significant rise of blood glucose, loss of renal function, severe kidney histopathology injuries and kidney fibrosis, increase of renal HIF-1α expression, and aggravated oxidative stress and ERS. Whilst there were no significant changes in blood glucose, YC-1 treatment notably reduced kidney weight/body weight ratio, serum creatinine, UACR, and urine NGAL levels in db/db mice. YC-1 treatment ameliorated kidney histopathology injuries and kidney fibrosis, and decreased the expressions of collagen-Ⅰ and α-SMA. YC-1 treatment also reduced the number of TUNEL positive cells, the expression of HIF-1α and pro-apoptotic proteins including BAX and cleaved caspase-3, and MDA level in the kidneys of db/db mice, while promoting anti-apoptotic protein BCL-2 expression and SOD activity. The expressions of ERS markers GRP78, p-PERK, p-eIF2α, ATF4, and CHOP were likewise significantly decreased in DB+YC-1 group.Conclusion·HIF-1α inhibitor YC-1 inhibits oxidative stress and abnormal activation of ERS, improving cell apoptosis and fibrosis in the kidneys of DN mice, which would attenuate the aggravation of pathological damage and loss of kidney function

How to model and implement connections between physical and virtual models for digital twin application

Digital twin (DT) is a virtual mirror (representation) of a physical world or a system along its lifecycle. As for a complex discrete manufacturing system (DMS), it is a digital model for emulating or reproducing the functions or actions of a real manufacturing system by giving the system simulation information or directly driven by a real system with proper connections between the DT model and the real-world system. It is a key building block for smart factory and manufacturing under the Industry 4.0 paradigm. The key research question is how to effectively create a DT model during the design stage of a complex manufacturing system and to make it usable throughout the system's lifecycle such as the production stage. Given that there are some existing discussions on DT framework development, this paper focuses on the modeling methods for rapidly creating a virtual model and the connection implementation mechanism between a physical world production system at a workshop level and its mirrored virtual model. To reach above goals, in this paper, the discrete event system (DES) modeling theory is applied to the three-dimension DT model. First, for formally representing a manufacturing system and creating its virtual model, seven basic elements: controller, executor, processor, buffer, flowing entity, virtual service node and logistics path of a DMS have been identified and the concept of the logistics path network and the service cell is introduced to uniformly describe a manufacturing system. Second, for implementing interconnection and interaction, a new interconnection and data interaction mechanism between the physical system and its virtual model for through-life applications has been designed. With them, each service cell consists of seven elements and encapsulates input/output information and control logic. All the discrete cells are constructed and mapped onto different production-process-oriented digital manufacturing modules by integrating logical, geometric and data models. As a result, the virtual-physical connection is realized to form a DT model. The proposed virtual modeling method and the associated connection mechanism have been applied to a real-world workshop DT to demonstrate its practicality and usefulness

Bi-level dynamic scheduling architecture based on service unit digital twin agents

Pure reactive scheduling is one of the core technologies to solve the complex dynamic disturbance factors in real-time. The emergence of CPS, digital twin, cloud computing, big data and other new technologies based on the industrial Internet enables information acquisition and pure reactive scheduling more practical to some extent. However, how to build a new architecture to solve the problems which traditional dynamic scheduling methods cannot solve becomes a new research challenge. Therefore, this paper designs a new bi-level distributed dynamic workshop scheduling architecture, which is based on the workshop digital twin scheduling agent and multiple service unit digital twin scheduling agents. Within this architecture, scheduling a physical workshop is decomposed to the whole workshop scheduling in the first level and its service unit scheduling in the second level. On the first level, the whole workshop scheduling is executed by its virtual workshop coordination (scheduling) agent embedded with the workshop digital twin consisting of multi-service unit digital twins. On the second level, each service unit scheduling coordinated by the first level scheduling is executed in a distributed way by the corresponding service unit scheduling agent associated with its service unit digital twin. The benefits of the new architecture include (1) if a dynamic scheduling only requires a single service unit scheduling, it will then be performed in the corresponding service unit scheduling without involving other service units, which will make the scheduling locally, simply and robustly. (2) when a dynamic scheduling requires changes in multiple service units in a coordinated way, the first level scheduling will be executed and then coordinate the second level service unit scheduling accordingly. This divide-and-then-conquer strategy will make the scheduling easier and practical. The proposed architecture has been tested to illustrate its feasibility and practicality

Development of a Fully Human Anti-PDGFRβ Antibody That Suppresses Growth of Human Tumor Xenografts and Enhances Antitumor Activity of an Anti-VEGFR2 Antibody

Platelet-derived growth factor receptor β (PDGFRβ) is upregulated in most of solid tumors. It is expressed by pericytes/smooth muscle cells, fibroblast, macrophage, and certain tumor cells. Several PDGF receptor-related antagonists are being developed as potential antitumor agents and have demonstrated promising antitumor activity in both preclinical and clinical settings. Here, we produced a fully human neutralizing antibody, IMC-2C5, directed against PDGFRβ from an antibody phage display library. IMC-2C5 binds to both human and mouse PDGFRβ and blocks PDGF-B from binding to the receptor. IMC-2C5 also blocks ligand-stimulated activation of PDGFRβ and downstream signaling molecules in tumor cells. In animal studies, IMC-2C5 significantly delayed the growth of OVCAR-8 and NCI-H460 human tumor xenografts in nude mice but failed to show antitumor activities in OVCAR-5 and Caki-1 xenografts. Our results indicate that the antitumor efficacy of IMC-2C5 is primarily due to its effects on tumor stroma, rather than on tumor cells directly. Combination of IMC-2C5 and DC101, an anti-mouse vascular endothelial growth factor receptor 2 antibody, resulted in significantly enhanced antitumor activity in BxPC-3, NCI-H460, and HCT-116 xenografts, compared with DC101 alone, and the trend of additive effects to DC101 treatment in several other tumor models. ELISA analysis of NCI-H460 tumor homogenates showed that IMC-2C5 attenuated protein level of vascular endothelial growth factor and basic fibroblast growth factor elevated by DC101 treatment. Finally, IMC-2C5 showed a trend of additive effects when combined with DC101/chemotherapy in MIA-PaCa-2 and NCI-H460 models. Taken together, these results lend great support to the use of PDGFRβ antagonists in combination with other antiangiogenic agents in the treatment of a broad range of human cancers

Superiority of integrated cervicothoracic immobilization in the setup of lung cancer patients treated with supraclavicular station irradiation

ObjectiveTo investigate the superiority of the integrated cervicothoracic immobilization devices (ICTID) on the mobility of the supraclavicular station in lung cancer patients requiring both primary lung lesion and positive supraclavicular lymph nodes irradiation.MethodsOne hundred patients with lung cancer were prospectively enrolled in the study. The following four different fixation methods are used for CT simulation positioning: thoracoabdominal flat immobilization device fixation with arms lifting (TAFID group), head-neck-shoulder immobilization device fixation with arms on the body sides (HNSID group), ICTID fixation with arms on the body sides (ICTID arms-down group), and n ICTID fixation with arms lifting (ICTID arms-up group). Cone-beam computed tomography (CBCT) images are taken daily or weekly before treatment, to assess anatomical changes during the radiotherapy course.ResultsThe translation errors in X (left-right direction), Y (head-foot direction), and Z (abdomen-back direction) directions of the ICTID arms-up, TAFID, ICTID arms-down and HNSID groups were (0.15 ± 0.18) cm, (0.15 ± 0.16) cm, (0.16 ± 0.16) cm, and (0.15 ± 0.20) cm; (0.15 ± 0.15) cm, (0.21 ± 0.25) cm, (0.28 ± 0.23) cm, and (0.27 ± 0.21) cm; (0.13 ± 0.14) cm, (0.15 ± 0.14) cm, (0.17 ± 0.13) cm, and (0.16 ± 0.14) cm, respectively. Among them, the ICTID arms-up group had the minimal setup errors in X direction than those in ICTID arms-down (p=0.001) and HNSID groups (p=0.001), and in Y direction than those in TAFID (p<0.001), and in Z direction than those in ICTID arms-down (p<0.001) and TAFID groups (p=0.034). For the rotational errors of the four groups in the directions of sagittal plane, transverse plane, and coronal plane, the ICTID arms-up group had the smallest setup errors in the sagittal plane than that of TAFID groups and similar rotation setup errors with those of the other three groups.ConclusionFor patients requiring radiation of primary lung lesion and positive supraclavicular lymph nodes, an integrated frame fixation device is preferred the ICTID arms-up methods provide the smallest set up error and satisfied repeatability of body position, compared with TAFID and HNSID