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Up-conversion single-photon detectors (UCSPD) are based on sum-frequency generation of the telecom band single-photons to near-infrared wavelengths at which efficient and low-noise silicon single-photon detectors are available. Moreover, because of high dynamic range of silicon single-photon detectors, UCSPD is suitable for high-speed quantum communication. UCSPDs reported to date, however, have a very narrow fixed window of detectable wavelengths, severely limiting their applications in wavelength-multiplexed quantum networks. In this work, we report a tunable UCSPD module that covers the complete telecom C band, making it suitable for quantum communication networks based on sharing wavelength-multiplexed entangled photons.

Four homalotine species-Anomognathus armatus (Sharp), Heterota onorum Maruyama, Neosilusa ceylonica (Kraatz), and Silusa lanuginosa Sharp-and three genera-Anomognathus Solier, Neosilusa Cameron, Silusa Erichson-are identified for the first time in Korea. The tribe Homalotini can be distinguished from other related tribes by the combination of the following characters: tarsal formula 4-4-5; mandible with patch or rows of denticles in ventral molar region; base of medial setae of prementum very close together, setal insertions in contact in many, setae displaced one behind the other in some; medial pseudopore field of prementum very narrow in many. Habitus photographs, diagnoses, and illustrations of male genitalia of these four species are provided.

Category: Ankle Arthritis; Sports Introduction/Purpose: Repetitive ankle sprains can cause various intra-articular pathologies, and there is a relatively clear consensus on the relationship between chronic ankle instability and osteoarthritis. However, information on the natural course in patients with chronic ankle instability and treatment options for preventing degenerative changes remain limited. This study aimed to compare the intermediate-term prognoses between patients with surgical and non-surgical treatment. Methods: This study included 44 patients who underwent lateral stabilization procedure (anatomical ligament repair or reconstruction) and 62 patients with conservative treatment for chronic ankle instability conjunction with early-stage arthritis of Takakura grade 2. Daily living and sport activities were evaluated using the Foot and Ankle Ability Measure (FAAM). Progression of osteoarthritis was evaluated through periodic weight-bearing radiographs. Additionally, the correlation between clinical evaluation score and the presence of progressive osteoarthritis was analyzed. Results: The FAAM score significantly improved from a mean of 48.8 points preoperatively to 83.6 points at final follow-up (p <.001) in the surgical group, while it also improved in the non-surgical group from a mean of 65.9 points to 74.1 points (p = 0.188). There was no significant difference in daily living ability of the FAAM score between the two groups at final follow-up (88.6 vs 81.4 points, p = 0.385), but the surgical group showed better results than the non-surgical group in sports ability (79.4 vs. 67.3 points, p <.001). The incidence of progression of osteoarthritis grade was not significantly different between surgery group (15.9%) and non-surgical group (17.7%) (p = 0.861). Conclusion: Patients with early medial osteoarthritis accompanied by chronic lateral ankle instability who underwent surgical and non-surgical treatment showed similar intermediate-term clinical outcomes. However, in terms of sports activity ability, the surgical group showed superior results compared to the non-surgical group. The radiological prognosis based on the Takakura grade of degenerative arthritis also showed similar results in both groups. There was a significant difference in clinical evaluation scores between patients with and without progressive osteoarthritis. [ABSTRACT FROM AUTHOR]

Up-conversion single-photon detectors (UCSPD) are based on sum-frequency generation of the telecom band single-photons to near-infrared wavelengths at which efficient and low-noise silicon single-photon detectors are available. Moreover, because of high dynamic range of silicon single-photon detectors, UCSPD is suitable for high-speed quantum communication. UCSPDs reported to date, however, have a very narrow fixed window of detectable wavelengths, severely limiting their applications in wavelength-multiplexed quantum networks. In this work, we report a tunable UCSPD module that covers the complete telecom C band, making it suitable for quantum communication networks based on sharing wavelength-multiplexed entangled photons. [ABSTRACT FROM AUTHOR]

We report a quantum random number generator based on the photon-number--path entangled state that is prepared by means of two-photon quantum interference at a beam splitter. The randomness in our scheme is truly quantum mechanical in origin since it results from the projection measurement of the entangled two-photon state. The generated bit sequences satisfy the standard randomness test. OCIS codes: 270.5585, 030.5260, 190.7110.

A new active clamping zero-voltage switching (ZVS) pulse-width modulation (PWM) current-fed half-bridge converter (CFHB) is proposed in this paper. Its active clamping snubber (ACS) can not only absorb the voltage surge across the turned-off switch, but also achieve the ZVS of all power switches. Moreover, it can be applied to all current-fed power conversion topologies and its operation as well as structure is very simple. Since auxiliary switches in the snubber circuit are switched in a complementary way to main switches, an additional PWM IC is not necessary. In addition, it does not need any clamp winding and auxiliary circuit besides additional two power switches and one capacitor while the conventional current-fed half bridge converter has to be equipped with two clamp windings, two ZVS circuits, and two snubbers. Therefore, it can ensure the higher operating frequency, smaller-sized reactive components, lower cost of production, easier implementation, and higher efficiency. The operational principle, theoretical analysis, and design considerations are presented. To confirm the operation, validity, and features of the proposed circuit, experimental results from a 200-W, 24-200 Vdc prototype are presented. Index Terms--DC/DC power conversion, snubbers, switched mode power supplies.

Category: Sports; Ankle Introduction/Purpose: Even after a considerable period following the modified Broström procedure, it is not uncommon for individuals to fail to fully regain their pre-injury sports activity capabilities. Return to sports activity can be influenced by various factors beyond the patient's determination (hope for sports activity), including residual pain or swelling, inadequate mechanical stability, deficits in postural control abilities or proprioception, among others. This study aimed to investigate the factors influencing the return to sports activity after anatomical ligament repair for chronic ankle instability. Methods: We conducted a study involving 62 patients under the age of 35 who underwent the modified Broström procedure for chronic ankle instability and were followed up for over 3 years. Among them, 51 patients (82.3%) were able to return to their pre-injury level of sports activity (return group), while 11 patients (17.7%) experienced some or significant limitations (non-return group). Clinical outcomes were evaluated using the Foot and Ankle Outcome Score (FAOS) and the Foot and Ankle Ability Measure (FAAM). Mechanical stability was assessed through physical examination and stress radiography. peroneal strength was evaluated using Biodex isokinetic dynamometer to measure peak torque and total work during eversion movement. Postural control abilities were analyzed using the static and dynamic stability assessment modes of Biodex posturography. Results: There was a significant difference between the two groups in FAOS pain (94.7 points in return group vs 85.1 points in non-return group, p=0.004) and sports (91.2 points vs 78.8 points, p<.001) subscales. In FAAM assessment, there was a significant difference in the sports activity (90.5 points vs 77.4 points, p<.001). Recurrence of mechanical instability was confirmed in 2 patients (3.9%) in the return group and 4 patients (36.4%) in the non-return group. There were no significant differences between the groups in evertor peak torque and total work. Regarding posturography assessment, static postural control ability(overall stability index) did not show significant differences between the groups, but significant differences were observed in dynamic postural control ability (1.4 vs 2.3, p=0.002). Conclusion: It has been analyzed that residual pain, recurrence of mechanical instability, and inadequate recovery of dynamic postural control ability affect the return to pre-injury level of sports activity after the modified Broström procedure for chronic ankle instability. It is deemed necessary to develop effective treatment strategies considering these factors during the rehabilitation process aimed at returning to sports activity after surgery. [ABSTRACT FROM AUTHOR]

Efficient photon–photon interaction is one of the key elements for realizing quantum information processing. The interaction, however, must often be mediated through an atomic medium due to the bosonic nature of photons, and the interaction time, which is critically linked to the efficiency, depends on the properties of the atom–photon interaction. While the electromagnetically induced transparency effect does offer the possibility of photonic quantum memory, it does not enhance the interaction time as it fully maps the photonic state to an atomic state. The stationary light pulse (SLP) effect, on the contrary, traps the photonic state inside an atomic medium with zero group velocity, opening up the possibility of enhanced interaction time. In this work, we report the first experimental demonstration of trapping a free-propagating single-photon into a cold atomic ensemble via the quantum SLP (QSLP) process. We conclusively show that the quantum properties of the single-photon state are preserved well during the QSLP process. Our work paves the way for new approaches for efficient photon–photon interactions, exotic photonic states, and many-body simulations in photonic systems. [ABSTRACT FROM AUTHOR]

In a quantum network involving multiple communicating parties, an important goal is to establish high-quality pairwise entanglement among the users without introducing multiple entangled-photon sources which would necessarily complicate the overall network setup. Moreover, it is preferable that the pairwise entanglement of photons is in the time-bin degree of freedom as the photonic time-bin qubit is ideally suited for fiber-optic distribution. Here, we report an experimental demonstration of a field-deployable quantum communication network involving multiple users, all of whom share pairwise entanglement in the time-bin degree of freedom of photons. In particular, by utilizing a single spontaneous-parametric down-conversion source which produces a broadband pair of photons and the wavelength-division demultiplexing/multiplexing technology, all the communicating parties within the network are always simultaneously ready for quantum communication. To further demonstrate the practical feasibility of a quantum network with time-bin entanglement over a wavelength-multiplexed fiber network, we demonstrate entangled-photon quantum key distribution with three users, each separated by 60 km of optical fibers. [ABSTRACT FROM AUTHOR]