A novel dual-channel thermo-optic locking method for the whispering gallery mode microresonator

Mode locking can be effectively achieved by using the thermo-optic effects in the whispering gallery mode(WGM)optical microcavity,without the help of external equipment.Therefore,it has the advantages of small size,low integration costs,and self-locking,which shows great potential for application.However,the conventional single-channel microcavity thermal-locking method that relies solely on internal thermal balance will inevitably be disturbed by the external environment.This limitation affects the locking time and stability.Therefore,in this paper,we propose a new method for closed-loop thermal locking of a dual-channel microcavity.The thermal locking of the signal laser and the thermal regulation of the control laser are carried out respectively by synchronously drawing a dual-path tapered fiber.The theoretical model of the thermal dynamics of the dual-channel microcavity system is established,and the influence of the control-laser power on the thermal locking of the signal laser is confirmed.The deviation between the locking voltage of the signal laser and the set point value is used as a closed-loop feedback parameter to achieve long-term and highly stable mode locking of the signal laser.The results show that in the 2.63 h thermal-locking test,the locking stability is an order of magnitude higher than that of the single tapered fiber.This solution addresses the issue of thermal locking being disrupted by the external environment,and offers new possibilities for important applications such as spectroscopy and micro-optical sensor devices.

Early Treatment Outcome of Humeral Shaft Fracture Non-Union in Adults: Comparative Study of Plating versus Interlocking Nailing

Background: Fractures of humeral shaft in adults are common injuries. Humeral shafts non-union either from late presentation after initial treatment by traditional bone setters or failed non-operative orthodox care is a major problem in this part of the world. This non-union is a major treatment challenge with increased cost of care and morbidity in this part of the world. Humeral shaft non-union can be treated with locked intra-medullary nailing (LIMN) or dynamic compression plating (DCP). Study on comparison of these methods of fixation in this part of the world is scarce in literature search, hence the reason for this study. Objective: The objectives of this study are: (1) to compare early clinical outcome following fixation of humeral shaft fracture nonunion with DCP versus LIMN;(2) to compare the time of radiologic fracture union of DCP with LIMN;(3) to compare complications following fixation of humeral shaft fracture nonunion with DCP versus LIMN. Patients and Methods: This was a randomized control study done for 2 years in which fifty adult patients with humeral shaft non-union were recruited. The patients were grouped into 2 (P = DCP & N = LIMN). Forty five of the patients completed the follow up periods of the study and then analyzed. The P group had ORIF with DCP while the N group had ORIF with LIMN. Both groups had grafting with cancellous bones. Each patient was followed up for a period of 6 months at the time which radiographic union is expected. Any patient without clinical and/or radiographic evidence of union after six months of surgery was diagnosed as having recurrent non-union. The data generated was analyzed using SPSS Version 23. The results were presented in charts and tables. The paired t-test was used while considering p value Result: Forty five patients completed follow up. There was a male preponderance (4:1), right humerus predominated (3:2). Motor vehicular accidents were the commonest cause of the fractures (62%). Most non-union fractures occurred at the level of the middle 3rd of the humeral shaft (60%). Failed TBS treatment was the commonest indication for the osteosynthesis (71%). More patients had plating (53%) compared to 47% who had LIMN. Most patients (93.4%) had union between 3 to 6 months irrespective of fixation type with no significant statistical difference between the union rate of DCP and LIMN (p value 0.06) with similar functional outcome and complication rates irrespective of the type of fixation. Conclusion: This study showed that the success rates in term of fracture union, outcome functional grades and complication rates were not directly dependent on the types of the fixation: plating or locked intra-medullary nailing.

Unlocking Cellular Mysteries:Advancements in Single-Cell Omics Analysis with Genome-Scale Metabolic Modeling

The widespread applications of single-cell technologies have generated a large amount of single-cell data,resulting in a growing need for single-cell data analysis and interpretation methods.While methods such as machine learning allow for single-cell data analysis,they cannot interpret the data very well.

Locking system strengthened by biomimetic mineralized collagen putty for the treatment of osteoporotic proximal humeral fractures

The current study is to observe the effect of the locking system strengthened by biomimetic mineralized collagen putty for the treatment of senile proximal humeral osteoporotic fractures.From January 2012 to December 2015,80 cases of senile patients with osteoporotic proximal humeral fractures were randomly divided into an observation group and a control group,each group with a total of 40 cases.The control group was simply treated with locking plate.The observation group was treated with locking plate in combination with biomimetic mineralized collagen putty.The therapeutic effect thereby was observed.The excellent and satisfactory rate was 90%in observation group and was 72.5%in control group.The difference between the two groups was statistically significant(χ^(2)=5.3312,P<0.05).The fracture healing time was 11.8263.62 weeks in observation group and 19.7865.46 weeks in control group.The shoulder joint function score was 89.6368.12 in observation group and 76.9268.18 in control group.There was significant difference between the two groups(t=7.1272;12.7834,P<0.05).The complication rate was 10%in the observation group and 32.5%in the control group(χ^(2)=7.3786,P<0.05).Locking system strengthened by biomimetic mineralized collagen putty has advantages such as accelerating healing of senile proximal humeral fracture,improving the therapeutic effect,reducing the complications.As one of the optimal internal fixation method,it provides a new option for better treatment of senile osteoporotic fracture.

Novel homodyne frequency-shifting interference pattern locking system

We present a novel homodyne frequency-shifting interference pattern locking system to enhance the exposure contrast of interference lithography and scanning beam interference lithography（SBIL）. The novel interference pattern locking system employs a special homodyne redundant phase measurement interferometer（HRPMI） as the sensor and an acousto-opto modulator（AOM） as the actuator. The HRPMI offers the highly accurate value as well as the direction recognition of the interference pattern drift from four quadrature interference signals. The AOM provides a very fine resolution with a high speed for phase modulation. A compact and concise system with a short optical path can be achieved with this new scheme and a small power laser head in tens of microwatts is sufficient for exposure and phase locking, which results in a relatively low-cost system compared with the heterodyne system. More importantly, the accuracy of the system is at a high level as well as having robustness to environmental fluctuation. The experiment results show that the short-time（4 s） accuracy of the system is 0.0481 rad e3σT at present. Moreover, the phase of the interference pattern can also be set arbitrarily to any value with a high accuracy in a relatively large range, which indicates that the system can also be extended to the SBIL application.

Improvements in Iodine Stabilized He-Ne Easers at 474 THz (633 nm) with Compatible System of Third and Fifth Harmonic Locking

We have developed two 474 THz(633 nm)new iodine stabilized He-Ne lasers with compatible system of third and fifth harmonic locking.The frequency stability is 1.0×10-11/ 1s and 3.5×10-12 / 10s with third harmonic locking,and corresponding values are 1.3×10-11/1s and 4.0×10-12/ 10s with fifth harmonic locking.We found that the frequency difference between the same component with third and fifth harmonic locking are from 5 kHz to SO kHz.Our experiment and analysis indicate that the center of fifth harmonic signals is closer to the Lorentzian center in iodine absorption component than one of the third harmonic signals,and the reproducibility with fifth harmonic locking is also better than one with third harmonic locking.

Partitioned k-Exclusion Real-Time Locking Protocol Motivated by Multicore Multi-GPU Systems

Graphic processing units （GPUs） have been widely recognized as cost-efficient co-processors with acceptable size, weight, and power consumption. However, adopting GPUs in real-time systems is still challenging, due to the lack in framework for real-time analysis. In order to guarantee real-time requirements while maintaining system utilization ~in modern heterogeneous systems, such as multicore multi-GPU systems, a novel suspension-based k-exclusion real-time locking protocol and the associated suspension-aware schedulability analysis are proposed. The proposed protocol provides a synchronization framework that enables multiple GPUs to be efficiently integrated in multicore real-time systems. Comparative evaluations show that the proposed methods improve upon the existing work in terms of schedulability.

Locking plates for distal fibula fractures in young and elderly patients:A retrospective study

BACKGROUND Ankle fractures are common injuries in the young and elderly populations.To prevent post-traumatic arthritis,an anatomic reconstruction of the ankle structure is mandatory.Open reduction and internal fixation is the treatment of choice among orthopaedics.Conventional plates allow stability of the fracture if bone quality is present.Locking plates might offer an advantage for the treatment of lateral malleolar fracture in patients with comminution,severe instability,distal fractures,or osteoporotic bone.Our hospital introduced a new locking plate for fracture of the distal fibula.AIM To evaluate locking plates in terms of outcomes and complications in young and elderly patients.METHODS We retrospectively reviewed a total of 67 patients treated for displaced distal fibula fractures.Demographic data,number of comorbidities,use of inter fragmentary screw,complication,time of fracture healing,partial or full weight bearing,and reoperation were recorded for all patients.Clinical outcome was assessed by the American Orthopedic Foot and Ankle Society clinical scoring system.Radiographs were obtained at 4,8,12,16,20,and 24 wk until radiographic union was obtained.RESULTS All patients displayed complete bony union on radiographic assessment,and no patients developed any serious complications.We observed two superficial infections,one delayed wound healing,and two plate intolerances.Significant differences were observed between the two age groups in terms of radiographic healing(11.9 wk in younger patients vs 13.7 wk in older patients;P=0.011)and in the American Orthopedic Foot and Ankle Society score at 6 mo after surgery(88.2 in younger patients vs 86.0 in older patients;P=0.001)and at 12 mo after surgery(92.6 in younger patients vs 90.0 in older patients;P=0.000).CONCLUSION Locking plates provide a stable and rigid fixation in multifragmentary and comminuted fractures or in the presence of poor bone quality.

Quantum Locking and the Meissner Effect Lead to the Origin and Stability of the Saturn Rings System

It is demonstrated how superconducting iced particles of the protoplanetary cloud of Saturn are coming to magnetic equator plane and create the stable enough rings disk. There are two steps. First, after appearance of the Saturn magnetic field due to Meissner phenomenon, all particles orbits are moving to the magnetic equator plane. Finally they become distributed as rings and gaps like iron particles around magnet on laboratory table. And they are separated from each other by the magnetic field expelled from them. It takes up to few tens of thousands years with ten meters rings disk thickness. Second, because of quantum locking all particles become to be locked within magnetic well at the magnetic equator plane due to Abrikosov vortex for superconductor. Finally each particle is locked within three-dimensional magnetic well. It works even when particles have small fraction of superconductor. During the rings evolution some contribution to the disk also could come from the collision-generated debris of the current moon, coming meteorites and from the geysers like it happened due to magnetic coupling of Saturn and Enceladus. The rings are relict of the early days of the magnetic field of Saturn system.

Perspectives of spin-valley locking devices

Valleytronics is an emerging field of research which utilizes the valley degree of freedom to encode information.However,it is technically nontrivial to produce a stable valley polarization and to achieve efficient control and manipulation of valleys.Spin–valley locking refers to the coupling between spin and valley degrees of freedom in the materials with large spin–orbit coupling(SOC)and enables the manipulation of valleys indirectly through controlling spins.Here,we review the recent advances in spin–valley locking physics and outline possible device implications.In particular,we focus on the spin–valley locking induced by SOC and external electric field in certain two-dimensional materials with inversion symmetry and demonstrate the intriguing switchable valley–spin polarization,which can be utilized to design the promising electronic devices,namely,valley-spin valves and logic gates.

An injection-locking diode laser at 671 nm with a wide tuning range up to 6 GHz

We present a compact injection-locking diode laser module to generate 671 nm laser light with a high output power up to 150 m W.The module adopts a master-slave injection-locking scheme,and the injection-locking state is monitored using the transmission spectrum from a Fabry-Perot interferometer.Beat frequency spectrum measurement shows that the injection-locked slave laser has no other frequency components within the 150-MHz detection bandwidth.It is found that without additional electronic feedback,the slave laser can follow the master laser over a wide range of 6 GHz.All the elements of the module are commercially available,which favors fast construction of a complete 671-nm laser system for the preparation of cold^(6)Li atoms with only one research-grade diode laser as the seeding source.

Knee locking caused by osteochondroma of the proximal tibia adjacent to the pes anserinus:A case report

BACKGROUND Osteochondroma is one of the most common benign bone tumors,and it may cause bone and joint deformities and limited range of motion of an adjacent joint.The pes anserinus region is one of the most frequent sites of osteochondroma,but knee locking caused by osteochondromas in the pes anserinus region is extremely rare.CASE SUMMARY We describe a 13-year-old Japanese girl’s extra-articular knee locking that occurred when the semitendinosus tendon got caught in osteochondroma that had developed in the pes anserinus region.The osteochondroma was surgically resected.The postoperative outcome has been excellent,with no recurrence of knee locking or tumor one-year post-surgery.CONCLUSION When a young person develops knee locking,the possibility of extra-articular as well as intra-articular locking should be considered.Osteochondroma,one of the causes of extra-articular locking,can be treated with surgery with good postoperative results.

Triggering,clicking,locking and crepitus of the finger:A comprehensive overview

Triggering,locking,clicking,and crepitus of the fingers are common symptoms patients present with.Even though crepitus and triggering can occur as part of the same underlying diagnosis,it is important to differentiate between them,as they usually indicate different possible diagnoses.The differential diagnoses that should be considered include trigger finger,metacarpophalangeal joint(MCPJ)arthritis,fractures or dislocations,extensor digitorum communis subluxation or dislocation,locked MCPJ,avascular necrosis of the metacarpal head,and Dupuytren’s disease.A thorough clinical examination with appropriate special investigations can permit the clinician to make the correct diagnosis.Appropriate management of a confirmed diagnosis is successful in providing symptomatic improvement.

Unlocking the Brain’s Gateway to Methamphetamine Addiction

What secret molecular key enables methamphetamine,or meth for short,to ruthlessly hijack the brain’s reward system,leading countless individuals down spiral paths of addiction?Thanks to innovative research reported this month in Nature,we finally have critical clues.

Fixation of Calcaneal Tuberosity Beavis II Fracture in Elderly Patients Using Locking Plate Combined with Tension Screw

Background:Calcaneus is the largest bone of foot and the main load-bearing structure of heel.The incidence of simple calcaneal tubercle avulsion fracture is low,accounting for about 1%to 3%of all calcaneal fractures.Beavis II fracture has large bone fracture,obvious displacement,obvious soft tissue irritation,and often leads to skin necrosis.It needs surgical treatment,reduction and fixation as soon as possible.Although open reduction and tension screw internal fixation is used for Beavis II calcaneal tubercle fracture,but the failure rate is more common.Methods:This study retrospectively analyzed the surgical treatment of calcaneal tubercle Beavis II fracture over 55 years old in our hospital from January 2013 to January 2019.The patients were treated with tension screw combined with locking plate,and followed up and analyzed.Results:12 patients in this group were followed up for 12 to 36 months(mean 20 months).After operation,the fracture healed smoothly in all patients,the healing time was 8 to 12 weeks(mean 10.7 weeks),and there were no complications such as poor incision healing,fracture displacement,internal fixation loosening,fracture and so on.When the patients were followed up 18 weeks after operation,the AOFAS score was 47 to 100,with an average of 91.1,of which 8 cases were excellent,3 good and 1 poor,with an excellent and good rate of 91.7%.Conclusion:Our hospital has been treated with tension screw combined with locking plate,fixed firmly,can early functional exercise,achieved good results.

克服“Locking”发散性的有限元研究进展

从克服Ｌｏｃｋｉｎｇ发散性到高性能格式的研究发展是过去十年有限元法研究的一个重要方面．本文认为所谓高性能有限元方法是一种特别的低阶位移格式，它具有如下的理论和计算优点：（１）保持物理力学问题固有的数学物理特征；（２）因此，应用于工程数值模拟，它是“鲁棒”的、高效的．按此立场，评论介绍了在计算结构力学和计算流体力学中发展的克服两类Ｌｏｃｋｉｎｇ发散性的有限元方法．

On the generation of high-quality Nyquist pulses in mode-locked fiber lasers

Nyquist pulses have wide applications in many areas,from electronics to optics.Mode-locked lasers are ideal platforms to generate such pulses.However,how to generate high-quality Nyquist pulses in mode-locked lasers remains elusive.We address this problem by managing different physical effects in mode-locked fiber lasers through extensive numerical simulations.We find that net dispersion,linear loss,gain and filter shaping can affect the quality of Nyquist pulses significantly.We also demonstrate that Nyquist pulses experience similariton shaping due to the nonlinear attractor effect in the gain medium.Our work may contribute to the design of Nyquist pulse sources and enrich the understanding of pulse shaping dynamics in mode-locked lasers.

Dissipative soliton resonance within different dispersion regimes in a single mode-locked laser

Dissipative soliton resonance(DSR) was previously studied in separated mode-locked fiber lasers within different dispersion regimes including anomalous, near-zero and normal dispersion. Here we propose a method to study DSR in a single mode-locked laser in these different dispersion regimes. This is achieved by virtue of a waveshaper which can control the laser dispersion readily using software, avoiding the usual tedious cutback method. We find that dispersion has a negligible effect on DSR since the pulse duration keeps constant while dispersion is varied. Moreover, we examine the dynamics of DSR on the parameters of the SA including modulation depth and saturation power, and find that the pulse duration can be changed in a large range when the saturation power is decreased. Our numerical simulations could be important to guide relative experimental studies.

Phase-locked single-mode terahertz quantum cascade lasers array

We demonstrated a scheme of phase-locked terahertz quantum cascade lasers(THz QCLs)array,with a single-mode pulse power of 108 mW at 13 K.The device utilizes a Talbot cavity to achieve phase locking among five ridge lasers with first-order buried distributed feedback(DFB)grating,resulting in nearly five times amplification of the single-mode power.Due to the optimum length of Talbot cavity depends on wavelength,the combination of Talbot cavity with the DFB grating leads to better power amplification than the combination with multimode Fabry-Perot(F-P)cavities.The Talbot cavity facet reflects light back to the ridge array direction and achieves self-imaging in the array,enabling phase-locked operation of ridges.We set the spacing between adjacent elements to be 220μm,much larger than the free-space wavelength,ensuring the operation of the fundamental supermode throughout the laser's dynamic range and obtaining a high-brightness far-field distribution.This scheme provides a new approach for enhancing the single-mode power of THz QCLs.

Electric modulation of the Fermi arc spin transport via three-terminal configuration in topological semimetal nanowires

Spin–momentum locking is a key feature of the topological surface state, which plays an important role in spintronics.The electrical detection of current-induced spin polarization protected by the spin–momentum locking in nonmagnetic systems provides a new platform for developing spintronics, while previous studies were mostly based on magnetic materials.In this study, the spin transport measurement of Dirac semimetal Cd_(3)As_(2) was studied by three-terminal geometry, and a hysteresis loop signal with high resistance and low resistance state was observed. The hysteresis was reversed by reversing the current direction, which illustrates the spin–momentum locking feature of Cd_(3)As_(2). Furthermore, we realized the on–off states of the spin signals through electric modulation of the Fermi arc via the three-terminal configuration, which enables the great potential of Cd_(3)As_(2) in spin field-effect transistors.