Random-Gate-Voltage Induced Al’tshuler–Aronov–Spivak Effect in Topological Edge States

Helical edge states are the hallmark of the quantum spin Hall insulator. Recently, several experiments have observed transport signatures contributed by trivial edge states, making it difficult to distinguish between the topologically trivial and nontrivial phases. Here, we show that helical edge states can be identified by the random-gate-voltage induced Φ 0/2-period oscillation of the averaged electron return probability in the interferometer constructed by the edge states. The random gate voltage can highlight the Φ 0/2-period Al’tshuler–Aronov–Spivak oscillation proportional to sin2(2πΦ/Φ 0) by quenching theΦ 0-period Aharonov–Bohm oscillation. It is found that the helical spin texture induced π Berry phase is key to such weak antilocalization behavior with zero return probability at Φ = 0. In contrast, the oscillation for the trivial edge states may exhibit either weak localization or antilocalization depending on the strength of the spin-orbit coupling, which has finite return probability at Φ = 0. Our results provide an effective way for the identification of the helical edge states. The predicted signature is stabilized by the time-reversal symmetry so that it is robust against disorder and does not require any fine adjustment of system.

A Novel Distal Interlocking Screw Guidance System Using a Laser Pointer and a Mechanical Fine-Adjustment Device

In minimally invasive bone fracture reduction surgery, broken femur bones are firmly fixed to a metallic intramedullary nail (IMN) after they are properly aligned. One of the greatest challenges of this process is that surgeons cannot directly see holes on the IMN, which increases the difficulty of the procedure and results in the requirement of taking a large number of X-ray images to find the location and direction of holes. We propose a novel distal interlocking screw guidance system that consists of a parallel guidance system using a laser pointer (PGSLP) and a mechanical fine-adjustment device (FAD). The PGSLP is used to make the planes of the C-arm and FAD parallel. The FAD is used to concentrically align the IMN hole with the guiding hole. The performance of the proposed device was evaluated by a series of experiments. The tilted angle error between the C-arm and FAD was measured to be 1.24 ± 0.715°. The translational error between the IMN hole and guiding hole was measured to be 0.378 ± 0.120 mm. Since the proposed guiding system is simple, cost-effective, and accurate, we expect it will soon be used in real operations.

A Comparative Study of Multi-form Steam Generators Using Concentrated Solar Power

Solar energy reaching Earth can be used as promising renewable energy to overcome the challenges of steam generation processes. Solar concentrators suffer from fine adjustment of solar radiation concentration and high investment cost. Therefore, multi-configuration receivers named the cylindrical cavity receiver, helical receiver, and the absorber-evaporator-tank have been manufactured from the coiled copper tube and brass plates, respectively. Then, they are tested and compared to improve the performance of steam generators. The performance of the absorber-evaporator-tank receiver has been compared with the cylindrical cavity receiver and helical receiver for a period from 10 am to 12 pm. The present investigation shows that the boiling point of water increasing when the pressure of generated steam increases particularly inside the coiled tube, which affects the dryness fraction of the generated steam. The present results show that the efficiency of the absorber-evaporator-tank is greater than the cylindrical cavity and helical receivers for the tested period. It is found that the thermal efficiency for the absorber-evaporator-tank doubles at noon, which indicates an effective solar receiver for generating steam.

Surgical Drill Guide for Insertion of an Infra-Acetabular Screw Based on an Anatomically Precontoured Plate System: A Cadaveric Study

Purpose. Due to the anatomic structure of the pelvis, free-hand placement of screws in the acetabular fracture management can be difficult. Infra-acetabular screw fixation increases acetabular stability by distal fixation of the cup. Aim of this cadaveric study is to investigate if a plate-referenced drill guide can provide save placement of an infra-acetabular screw over a precontoured suprapectineal quadrilateral buttress plate (SQBP). Methods. We constructed a drill guide for an infra-acetabular screw based on the surface of an anatomically precontoured SQBP. A total of 12 adult cadaveric acetabular specimens were used for drill guide-assisted placement of the infra-acetabular screw. The drill guide contains a radiopaque spiral to allow longitudinal fine adjustment of the SQBP along the pelvic brim to assure correct position of the plate-drill-guide construct in relation to the Koehler’s teardrop. After screw placement, we conducted a computed tomography (CT) scan of all specimens to assess the actual position of the screw in relation of the infra-acetabular corridor and the acetabular joint surface. Results. The position of the screw was within the infra-acetabular corridor in all cases. We did not see any intra-articular or intrapelvic screw penetration. The mean distance of the centerline of the screw to the medial border of the infra-acetabular corridor was 3.35 mm. The secure distance to the virtual surface of the femoral head to was 7.3 mm. Conclusions. A plate-referenced drill guide can provide safe placement of an infra-acetabular screw for treatment of acetabular fractures. Radiographic fine adjustment is necessary to access the optimal entry point.

Crosstalk Between Trophoblasts and Decidual Immune Cells: The Cornerstone of Maternal-Fetal Immunotolerance

The success of pregnancy relies on the fine adjustment of the maternal immune system to tolerate the allogeneic fetus. Trophoblasts carrying paternal antigens are the only fetal-derived cells that come into direct contact with the maternal immune cells at the maternal–fetal interface. The crosstalk between trophoblasts and decidual immune cells (DICs) via cell–cell direct interaction and soluble factors such as chemokines and cytokines is a core event contributing to the unique immunotolerant microenvironment. Abnormal trophoblasts–DICs crosstalk can lead to dysregulated immune situations, which is well known to be a potential cause of a series of pregnancy complications including recurrent spontaneous abortion (RSA), which is the most common one. Immunotherapy has been applied to RSA. However, its development has been far less rapid or mature than that of cancer immunotherapy. Elucidating the mechanism of maternal–fetal immune tolerance, the theoretical basis for RSA immunotherapy, not only helps to understand the establishment and maintenance of normal pregnancy but also provides new therapeutic strategies and promotes the progress of immunotherapy against pregnancy-related diseases caused by disrupted immunotolerance. In this review, we focus on recent progress in the maternal–fetal immune tolerance mediated by trophoblasts–DICs crosstalk and clinical application of immunotherapy in RSA. Advancement in this area will further accelerate the basic research and clinical transformation of reproductive immunity and tumor immunity.

Effective Design of Graphene Patch Arrays for Adjustable Plane-Wave Scattering

In this paper, the scattering properties of graphene patches are investigated to design arrays that are able to control effectively plane wave propagation. Initially, single patches are examined in terms of their radar cross-section and surface wave generation. Moreover, an array of four identical elements is designed and thoroughly investigated indicating that electrostatic bias field has not a significant effect. However, the application of non-uniform biasing on the same setup reveals the fine adjustment of the scattered wave’s main lobe direction.

Magnetic resonance imaging-guided disc–condyle relationship adjustment via articulation: a technical note and case series

A normal disc–condyle relationship is crucial to the health and function of the temporomandibular joint. We herein introduce a novel technique that can precisely and rapidly restore the disc–condyle relationship. An initial bite rim was made, and the patient was instructed to wear this bite rim during magnetic resonance imaging (MRI) scanning. A quick MRI scan was performed, and the disc–condyle relationship and direction and vector of the displacement was measured. Adjustments to the mandible position were made on an articulator based on the measurements, after which a second bite rim was made. A second quick preview MRI scan was immediately performed, and the images were evaluated and measured again. Additional adjustments were made as needed, and the preview scan was repeated until an ideal disc–condyle relationship was achieved. Once a good disc–condyle relationship was acquired, the mandible position was recorded as the treatment mandible position, and a splint was fabricated. MRI visualization enabled precise and very fine adjustment of the disc–condyle relationship by articulating. This technique might help to simplify the clinical process and improve treatment effectiveness.

Analysis of the Mechanisms for Compensation in Clock B

This chapter assesses the design requirements of the grasshopper escapement, the pendulum and suspension spring to provide compensation for changing density and viscosity of the air surrounding the pendulum and changing escapement torque. It assesses the key components of the Harrison system: a pendulum bob of modest mass; a pendulum operating at a large running arc; and the grasshopper escapement’s increased torque delivery, ability to run without lubrication, its composers that allow fine adjustment to the torques delivered before and after the escaping arcs are reached and the importance of the thickness of the suspension spring that runs within circular cheeks. It also compares the system to the traditional pendulum clock design that traditionally employs a pendulum with a large mass and high-quality factor—high Q. Furthermore, it discusses Harrison’s stipulation that the pendulum needed to slightly reduce its length when warm.