On the nonintegrability of equations for long- and short-wave interactions

We examine the integrability of two models used for the interaction of long and short waves in dispersive media. One is more classical but arguably cannot be derived from the underlying water wave equations, while the other one was recently derived. We use the method of Zakharov and Schulman to attempt to construct conserved quantities for these systems at different orders in the magnitude of the solutions. The coupled KdV-NLS model is shown to be nonintegrable, due to the presence of fourth-order resonances. A coupled real KdV - complex KdV system is shown to suffer the same fate, except for three special choices of the coefficients, where higher-order calculations or a different approach are necessary to conclude integrability or the absence thereof.Comment: 9 pages, presented as a poster at The Tenth IMACS International Conference on Nonlinear Evolution Equations and Wave Phenomena: Computation and Theor

A Flexible Electronic Helical Guide Controller

AbstractIn this paper, an Electronic Helical Guide Controller (EHGC) is proposed, for helical gear shaping processes. In most traditional gear shaper machines, the cutter's reciprocating movement is driven by a crank-connecting rod mechanism. Therefore, this study adopts this kind of gear shaper as the machine platform to establish an accurate mathematical model. The control algorithm is embedded in the interpolation module of the CNC system using electronic gearbox techniques to realize special multi-axis linkage control requirements. The crankshaft's angular position is measured and the rotational speed is calculated in each control cycle. The actual position and velocity of the cutter along the Z-axis can be calculated using the geometric relations of the crank-connecting mechanism, and motion in the other axes can be controlled by the electronic gearbox. A special G code with parameters (G83) is also designed and the EHGC control through NC programming is realized in an improvised gear shaping CNC machine. The proposed EHGC is low cost and easy to implement in practice since it does not need a linear grating ruler and a probe on the Z-axis. Furthermore, EHGC allows the flexibility to change a part's helix angle to compensate for distortions caused by heat treatment. Simulations and experiments are performed to verify the effectiveness of the proposed EHGC

Identification of related long non-coding RNAs and mRNAs in subclinical hypothyroidism complicated with type 2 diabetes by transcriptome analysis — a preliminary study

Introduction: The pathology mechanism of subclinical hypothyroidism and subclinical hypothyroidism complicated with type 2 diabetes remained uncertain. We aimed to find potential related long non-coding RNAs (lncRNAs) and mRNAs in the above diseases. Material and methods: Transcriptome sequencing was performed in three patients with subclinical hypothyroidism (S), three patients with subclinical hypothyroidism complicated with type 2 diabetes (SD), and three healthy controls (N). Differentially expressed mRNAs (DEmRNAs) and differentially expressed lncRNAs (DElncRNAs) were screened in S vs. N, SD vs. N, and SD vs. S group, and the nearby and co-expressed DEmRNAs of DElncRNAs were screened in S vs. N and SD vs. N. Moreover, functional analysis of DEmRNAs was then performed by Metascape. Results: In total, 465, 1058, and 943 DEmRNAs were obtained in S vs. N, SD vs. N, SD vs. S, respectively, and 191 overlapping genes were obtained in S vs. N and SD vs. N group. Among which, LAIR2, PNMA6A, and SFRP2 were deduced to be involved in subclinical hypothyroidism, and GPR162, APOL4, and ANK1 were deduced to be associated with subclinical hypothyroidism complicated with type 2 diabetes. A total of 50, 100, and 88 DElncRNAs were obtained in S vs. N, SD vs. N and SD vs. S, respectively. Combining with the interaction network of DElncRNA-DEmRNA, PAX8-AS1, co-expressed with KIR3DL1, was identified to function in subclinical hypothyroidism, and JHDM1D-AS1, co-expressed with ANK1, was deduced to play a role in subclinical hypothyroidism complicated with type 2 diabetes. Conclusions: Dysfunctional lncRNAs and mRNAs may be involved in the development of subclinical hypothyroidism and subclinical hypothyroidism complicated with type 2 diabetes.

Rapid Diagnosis by Microfluidic Techniques

Pathogenic bacteria in an aqueous or airborne environments usually cause infectious diseases in hospital or among the general public. One critical step in the successful treatment of the pathogen-caused infections is rapid diagnosis by identifying the causative microorganisms, which helps to provide early warning of the diseases. However, current standard identification based on cell culture and traditional molecular biotechniques often depends on costly or time-consuming detection methods and equipments, which are not suitable for point-of-care tests. Microfluidic-based technique has recently drawn lots of attention, due to the advantage that it has the potential of providing a faster, more sensitive, and higher-throughput identification of causative pathogens in an automatic manner by integrating micropumps and valves to control the liquid accurately inside the chips. In this chapter, microfluidic techniques for serodiagnosis of amebiasis, allergy, and rapid analysis of airborne bacteria are described. The microfluidic chips that integrate microcolumns, protein microarray, or a staggered herringbone mixer structure with sample to answer capability have been introduced and shown to be powerful in rapid diagnosis especially in medical fields

Vibration modal shapes and strain measurement of the main shaft assembly of a friction hoist

In order to evaluate the reliability of the main shaft unit of a friction hoisting system, strain measurement is a significant method. In this paper, a test rig of a friction hoisting system was built, which could applied periodically changing load on its main shaft unit; The mechanical analysis under the test load was conducted and the boundary limits were obtained; A three dimensional model of the main shaft unit was built in Pro-E and its finite element analysis was performed in ANSYS; With the analytical result, measuring points for strain rosettes were initially selected; Vibration modal shapes of the main shaft unit were analyzed, based on which Modal Assurance Criterion (MAC) was utilized in the Particle Swarm Optimization (PSO) algorithm to make the final decision of the number and positions of the measuring points; A wireless measurement system was developed to acquire strain signals from the optimized measuring positions; The test result verified the efficiency of the methods employed in this paper and revealed how strain of the main shaft unit changes during running process

Median mandibular flexure—the unique physiological phenomenon of the mandible and its clinical significance in implant restoration

Mandibular flexure, characterized by unique biomechanical behaviors such as elastic bending and torsion under functional loading, has emerged as a crucial factor in oral clinical diagnosis and treatment. This paper presents a comprehensive review of the current research status on mandibular flexure, drawing insights from relevant studies retrieved from the PubMed database (www.ncbi.nlm.nih.gov/pubmed), including research conclusions, literature reviews, case reports, and authoritative reference books. This paper thoroughly explores the physiological mechanisms underlying mandibular flexure, discussing different concurrent deformation types and the essential factors influencing this process. Moreover, it explores the profound implications of mandibular flexure on clinical aspects such as bone absorption around dental implants, the precision of prosthesis fabrication, and the selection and design of superstructure materials. Based on the empirical findings, this review provides crucial clinical recommendations. Specifically, it is recommended to exert precise control over the patients mouth opening during impression-taking. Those with a high elastic modulus or bone-tissue-like properties should be prioritized when selecting superstructure materials. Moreover, this review underscores the significance of customizing framework design to accommodate individual variations in facial morphology and occlusal habits. Future research endeavors in this field have the potential to advance clinical diagnosis and treatment approaches, providing opportunities for improvement