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Adenocarcinoma of the esophagogastric junction (AEG) has a high incidence, and the extent of lymph node dissection (LND) and its impact on prognosis remain controversial. This study aimed to explore the risk factors for lymph node metastasis (LNM) and prognosis in Siewert II/III AEG patients. A retrospective review of 239 Siewert II/III AEG patients surgically treated at Beijing Friendship Hospital from July 2013 to December 2022 was conducted. Preoperative staging was conducted via endoscopy, ultrasound gastroscopy, CT, and biopsy. Depending on the stage, patients received radical gastrectomy with LND and chemotherapy. Clinicopathological data were collected, and survival was monitored semiannually until November 2023. Utilizing logistic regression for data analysis and Cox regression for survival studies, multivariate analysis identified infiltration depth (ORâ =â 0.038, 95% CI: 0.011-0.139, Pâ <â .001), tumor deposit (ORâ =â 0.101, 95% CI: 0.011-0.904, Pâ =â .040), and intravascular cancer embolus (ORâ =â 0.234, 95% CI: 0.108-0.507, Pâ <â .001) as independent predictors of LNM. Lymph nodes No. 1, 2, 3, 4, 7, 10, and 11 were more prone to metastasis in the abdominal cavity. Notably, Siewert III AEG patients showed a higher metastatic rate in nodes No. 5 and No. 6 compared to Siewert II. Mediastinal LNM was predominantly found in nodes No. 110 and No. 111 for Siewert II AEG, with rates of 5.45% and 3.64%, respectively. A 3-year survival analysis underscored LNM as a significant prognostic factor (Pâ =â .001). Siewert II AEG patients should undergo removal of both celiac and mediastinal lymph nodes, specifically nodes No. 1, 2, 3, 4, 7, 10, 11, 110, and 111. Dissection of nodes No. 5 and No. 6 is not indicated for these patients. In contrast, Siewert III AEG patients do not require mediastinal LND, but pyloric lymphadenectomy for nodes No. 5 and No. 6 is essential. The presence of LNM is associated with poorer long-term prognosis. Perioperative chemotherapy may offer a survival advantage for AEG patients.
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Adenocarcinoma , Neoplasias Esofágicas , Neoplasias Gástricas , Humanos , Estudos Retrospectivos , Metástase Linfática/patologia , Neoplasias Gástricas/patologia , Neoplasias Esofágicas/patologia , Prognóstico , Excisão de Linfonodo , Adenocarcinoma/patologia , Junção Esofagogástrica/patologia , Fatores de RiscoRESUMO
Topological photonics provide a promising way to realize more robust optical devices against some defects and environmental perturbations. Quantum logic gates are fundamental units of quantum computers, which are widely used in future quantum information processing. Thus, constructing robust universal quantum logic gates is an important way forward to practical quantum computing. However, the most important problem to be solved is how to construct the quantum-logic-gate-required 2 × 2 beam splitter with topological protection. Here, the experimental realization of the topologically protected contradirectional coupler is reported, which can be employed to realize the quantum logic gates, including control-NOT and Hadamard gates, on the silicon photonic platform. These quantum gates not only have high experimental fidelities but also exhibit a certain degree of tolerances against certain types of defects. This work paves the way for the development of practical optical quantum computations and signal processing.
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Topological photonics provides a new degree of freedom to robustly control electromagnetic fields. To date, most of established topological states in photonics have been employed in Euclidean space. Motivated by unique properties of hyperbolic lattices, which are regular tessellations in non-Euclidean space with a constant negative curvature, the boundary-dominated hyperbolic topological states have been proposed. However, limited by highly crowded boundary resonators and complicated site couplings, the hyperbolic topological insulator has only been experimentally constructed in electric circuits. How to achieve hyperbolic photonic topological insulators is still an open question. Here, we report the experimental realization of hyperbolic photonic topological insulators using coupled ring resonators on silicon chips. Boundary-dominated one-way edge states with pseudospin-dependent propagation directions have been observed. Furthermore, the robustness of edge states in hyperbolic photonic topological insulators is also verified. Our findings have potential applications in the field of designing high-efficient topological photonic devices with enhanced boundary responses.
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Integrated quantum photonic circuit is a promising platform for the realization of quantum information processing in the future. To achieve the large-scale quantum photonic circuits, the applied quantum logic gates should be as small as possible for the high-density integration on chips. Here, we report the implementation of super-compact universal quantum logic gates on silicon chips by the method of inverse design. In particular, the fabricated controlled-NOT gate and Hadamard gate are both nearly a vacuum wavelength, being the smallest optical quantum gates reported up to now. We further design the quantum circuit by cascading these fundamental gates to perform arbitrary quantum processing, where the corresponding size is about several orders smaller than that of previous quantum photonic circuits. Our study paves the way for the realization of large-scale quantum photonic chips with integrated sources and can have important applications in the field of quantum information processes.
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We report on the first sub-60 fs pulse generated from a diode-pumped SESAM mode-locked Yb-laser based on a non-centrosymmetric Yb:YAl3(BO3)4 crystal as a gain medium. In the continuous-wave regime, pumping with a spatially single-mode, fiber-coupled 976â nm InGaAs laser diode, the Yb:YAl3(BO3)4 laser generated 391â mW at 1041.7â nm with a slope efficiency as high as 65.1%, and a wavelength tuning across 59â nm (1019 to 1078â nm) was achieved. By implementing a commercial SESAM to initiate and sustain the soliton type mode-locking, and using only a 1â mm-thick laser crystal, the Yb:YAl3(BO3)4 laser delivered pulses as short as 56 fs at a central wavelength of 1044.6â nm with an average output power of 76â mW at a pulse repetition rate of â¼67.55â MHz. To the best of our knowledge, this result represents the shortest pulses ever achieved from Yb:YAB crystal.
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Exceptional points (EPs) represent a distinct type of spectral singularity in non-Hermitian systems, and intriguing physics concepts have been studied with optical EPs recently. As a system beyond photonics, the mechanical oscillators coupling with many physical systems are expected to be further exploited EPs for mechanical sensing, topology energy transfer, nonreciprocal dynamics, etc. In this study, we demonstrated on-chip mechanical EPs with a silicon optomechanical zipper cavity, wherein two near-degenerate mechanical breathing modes are coupled via a single colocalized optical mode. By tailoring the dissipative and coherent couplings between two mechanical oscillators, the spectral splitting with 1/2 order response, a distinctive feature of EP, was observed successfully. Our work provides an integrated platform for investigating the physics related to mechanical EPs on silicon chips and suggests their possible applications for ultrasensitive measurements.
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Social media platforms have become the most prominent medium for spreading hate speech, primarily through hateful textual content. An extensive dataset containing emoticons, emojis, hashtags, slang, and contractions is required to detect hate speech on social media based on current trends. Therefore, our dataset is curated from various sources like Kaggle, GitHub, and other websites. This dataset contains hate speech sentences in English and is confined into two classes, one representing hateful content and the other representing non-hateful content. It has 451,709 sentences in total. 371,452 of these are hate speech, and 80,250 are non-hate speech. An augmented balanced dataset with 726,120 samples is also generated to create a custom vocabulary of 145,046 words. The total number of contractions considered in the dataset is 6403. The total number of bad words usually used in hateful content is 377. The text in each sentence of the final dataset, which is utilized for training and cross-validation, is limited to 180 words. The generated contractions dataset can be used for any projects in the area of NLP for data preprocessing. The augmented dataset can help to reduce the number of out-of-vocabulary words, and the hate speech dataset can be used as a classifier to detect hate or no hate on social media platforms.
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Energy transfer upconversion (ETU) coefficient plays a crucial role in investigating complex laser systems as it greatly influences both the laser output behavior and heat generation. For some quasi-three-energy-level lasers based on Er3+ doped, Ho3+ doped and codoped gain media, the available theoretical studies relied on some unreasonable approximations due to the lack of spectroscopic data, notably the ETU coefficient. We put forward what we believe is a novel approach to overcome the difficulties caused by wavelength jump occurred in aforementioned laser systems. Based on net gain cross-section analysis and rate equations modelling, the functional relationship between the ETU coefficient, the laser power and pump power at the jumping wavelength are established. ETU coefficients and their temperature dependences of Er,Yb:YAB crystals with different crystal doped concentrations are experimentally determined for the first time. The results reveal that the ETU process in Er,Yb:YAB laser system is 5â¼35 times stronger than that in Er3+ and Yb3+ codoped phosphate glass. The determination of these spectroscopic data paves the way for precise modelling of laser system based on Er,Yb:YAB or similar gain media.
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Lasers differ from other light sources in that they are coherent, and their coherence makes them indispensable to both fundamental research and practical application. In optomechanical cavities, photon and phonon lasing is facilitated by the ability of photons and phonons to interact intensively and excite one another coherently. The lasing linewidths of both phonons and photons are critical for practical application. This study investigates the lasing linewidths of photons and phonons from the underlying dynamics in an optomechanical cavity. We find that the linewidths can be accounted for by two distinct physical mechanisms in two regimes, namely the normal regime and the reversed regime, where the intrinsic optical decay rate is either larger or smaller than the intrinsic mechanical decay rate. In the normal regime, an ultra-narrow spectral linewidth of 5.4 kHz for phonon lasing at 6.22 GHz can be achieved regardless of the linewidth of the pump light, while these results are counterintuitively unattainable for photon lasing in the reversed regime. These results pave the way towards harnessing the coherence of both photons and phonons in silicon photonic devices and reshaping their spectra, potentially opening up new technologies in sensing, metrology, spectroscopy, and signal processing, as well as in applications requiring sources that offer an ultra-high degree of coherence.
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An eye-safe 1567 nm continuous-wave laser with a maximum output power of 50 mW and a slope efficiency of 21.1% was demonstrated in an Er:Yb:Ba3Gd(PO4)3 crystal. By using a Co2+:MgAl2O4 crystal with an initial transmission of 95% as a saturable absorber, a stable passively Q-switched pulsed laser was also realized in the crystal. The effects of the output coupler transmission and cavity length on pulsed performance were investigated. At an absorbed pump power of 350 mW, a 1541 nm Er:Yb:Ba3Gd(PO4)3 pulsed laser with a repetition frequency of 0.86 kHz, duration of 38 ns, energy of 21.2 µJ, and peak output power of 0.56 kW was obtained.
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Medicine is a fast-moving field, and the number of medical publications has increased rapidly over recent years. How to find relevant information from this vast pool of research effectively and efficiently has therefore become highly challenges. Previous studies have demonstrated that data fusion can improve search performance if properly utilized. However, in most cases effectiveness is the only concern and efficiency is not considered. A fusion-based system is by nature more complicated and expensive computationally than other retrieval models such as BM25, because many component retrieval systems and an extra layer of fusion are required. The number of component retrieval systems involved is an important indicator of complexity of the fusion-based system. We aim to select the optimal k-subset of component retrieval systems for any given number k, to optimize both fusion performance and reduce the cost of data fusion. A clustering-based approach is proposed. First all the candidates are divided into clusters by the Chameleon clustering algorithm, then representatives from every cluster are chosen by Sequential Forward Selection for fusion. Evaluated with two datasets from TREC, the proposed method performs more effectively than the other baseline methods including the state-of-the-art subset selection method significantly. When either of the two typical fusion methods is used, an improvement rate of over 10% is observed for both measures Mean Average Precision and Recall-level Precision, and an improvement rate of over 5% is observed for both measures Precision at 10 document level and Mean Reciprocal Rank.
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Algoritmos , Armazenamento e Recuperação da Informação , Análise por ConglomeradosRESUMO
Passively Q-switched Er:Yb:LuAl3(BO3)4 pulse microlasers were investigated at a low repetition frequency of 10-200 Hz. End-pumped by a 975.6 nm quasi-continuous-wave laser diode with pump pulse width of 0.5 ms and period of 10 ms, a stable 1522 nm pulse microlaser with single pulse energy of 48.3 µJ, duration of 1.9 ns, repetition frequency of 100 Hz, peak output power of 25.4 kW and beam quality factor less than 1.2 was realized at a pump beam waist diameter of 260 µm. This eye-safe passively Q-switched pulse microlaser with high peak output power and narrow duration can be used in the portable laser rangefinder.
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An optical neural network is proposed and demonstrated with programmable matrix transformation and nonlinear activation function of photodetection (square-law detection). Based on discrete phase-coherent spatial modes, the dimensionality of programmable optical matrix operations is 30â¼37, which is implemented by spatial light modulators. With this architecture, all-optical classification tasks of handwritten digits, objects and depth images are performed. The accuracy values of 85.0% and 81.0% are experimentally evaluated for MNIST (Modified National Institute of Standards and Technology) digit and MNIST fashion tasks, respectively. Due to the parallel nature of matrix multiplication, the processing speed of our proposed architecture is potentially as high as 7.4â¼74â T FLOPs per second (with 10â¼100â GHz detector).
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It has remained a big challenge to grow large crystals of compounds at very anisotropic crystal growth rates. GdPO4 is such an example, which usually grows into a needle-like shape. This work solved this problem by using Li+ ions, predicted by first-principles calculations, to adjust the crystal morphology of GdPO4. Based on the calculated surface energies and the polar properties of the surfaces, we identified two crystal planes, i.e. (-102) and (-111), which can be used to adjust the morphology of the GdPO4 crystal by using extrinsic cations in the flux system. With a predicted Li containing flux system, Li2O-MoO3-B2O3, a large crystal with a record size, 10.0 × 9.0 × 18.2 mm3, was grown by using the top-seeded solution growth (TSSG) method. Based on the grown large crystal and the polarized Raman measurements, four new Raman bands missing in early studies and other bands were unambiguously assigned. By introducing a new formula, the phonon-phonon interactions were shown to be weak in the temperature range from 83 to 803 K. Our study indicates that the crystal of GdPO4 can be used as a promising laser host material working under relatively high temperature conditions.
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Monodisperse Tb-doped NaCeF4 nanocrystals were synthesized via a hydrothermal method. The morphology, and room temperature and temperature dependent luminescent properties were investigated. Excited at 254 nm, the emissions of Ce3+ at 270-370 nm and those of Tb3+ at 475-700 nm can be observed. The strongest visible emission was observed in NaCeF4:20 at% Tb with a quantum yield of 49%. The efficiency of energy transfer from Ce3+ to Tb3+ increases with the Tb3+ doping concentration and reaches 95% for NaCeF4:30 at% Tb. The ratio of Tb3+ emission to Ce3+ emission is sensitive to temperature, and the relative sensitivity was calculated to be 1.0% °C-1 at 60 °C. The mechanisms for this thermal dependence were analyzed in terms of non-radiative relaxation and energy migration.
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We demonstrate a comprehensive characterization of the diode-pumped Yb:Bi4Si3O12 laser operating in the continuous-wave and soliton mode-locked regimes. Pumping with a 650 mW, single-transverse mode, fiber-coupled laser diode, a maximum continuous-wave output power amounted to 213 mW with a slope efficiency up to 57.6%. A broadband wavelength tuning range of more than 70 nm was achieved in CW regime with a fused silica prism. Applying a SESAM as mode locker, nearly transform-limited pulses as short as 113 fs were generated for a maximum average power of 53 mW and a pulse repetition rate of â¼106 MHz. To the best of our knowledge, this is the first report on passively mode-locked operation with the Yb:Bi4Si3O12 crystal.
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A single longitudinal-mode passively Q-switched 1537 nm pulse microchip laser was realized in an Er:Yb:Lu2Si2O7 crystal. The effects of the pump beam diameter and output mirror transmission on pulse characteristics of the Er:Yb:Lu2Si2O7 microchip laser were investigated, when a Co2+:MgAl2O4 saturable absorber with an initial transmission of 95% was used. At an absorbed pump power of 3.4 W, a 1537 nm single-longitudinal-mode pulse laser with energy of 25.8 µJ, repetition frequency of 0.89 kHz, duration of 4.3 ns, and peak output power of 6.0 kW was obtained, when the pump beam diameter and output mirror transmission were 420 µm and 3.0%, respectively. The beam quality factor of output laser with TEM00 mode was less than 1.3.
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OBJECTIVE: To evaluate the effectiveness of pedicled skin flap of foreskin for phalloplasty and Sugita surgical method in the treatment of complete concealed penis. METHODS: The clinical data of 46 children with complete concealed penis between January 2016 and January 2018 were analyzed retrospectively. Among which, 25 cases were treated with pedicled skin flap of foreskin for phalloplasty (group A) and 21 cases were treated with Sugita surgical method (group B) with an average age of 4.7 years (range, 2 years and 8 months to 11 years). At 3 months after operation, the concealed penis recovery was scored from three aspects of postoperative penis length (the difference of the penis length between at 3 months after operation and before operation), penis appearance, and skin appearance (the total score was 10). And the parents evaluation of satisfaction degree of penis exposure, penis appearance, and foreskin appearance after surgical correction was collected. RESULTS: Eighteen cases (72.0%) in group A and 15 cases (71.4%) in group B were followed up with an average of 13 months (range, 3-36 months). The incisions healed well in both groups, and there was no flap dehiscence, infection, necrosis, and penile erectile dysfunction. The penile length of the two groups increased significantly at 3 months after operation ( P<0.05); there was no significant difference between the two groups in terms of penis length and increased length at 3 months after operation and score of increase penis length after operation ( P>0.05). No penile retraction occurred in the two groups. And there was no significant difference between the two groups in penis appearance score, but the penis appearance score, skin appearance score, and total score of group A were significantly better than those of group B ( P<0.05). At 3 months after operation, the satisfaction rate of penis exposure in group A and group B was 88.9% and 80.0%, respectively, with no significant difference ( χ 2=0.50, P=0.48); the satisfaction rate of penis appearance was 72.2% and 53.3%, and the satisfaction rate of foreskin appearance was 94.4% and 53.3%, respectively, and the differences were significant ( χ 2=5.13, P=0.03; χ 2=7.53, P=0.01). CONCLUSION: Both surgical methods are suitable for correction of complete concealed penis, and the penile length gets a satisfactory recovery. However, the lymphedema of the prepuce after Sugita surgical method is serious, which can easily lead to poor appearance of the penis after operation. In general, the effectiveness of pedicled skin flap of foreskin for phalloplasty is better than that of the Sugita surgical method.
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Prepúcio do Pênis , Procedimentos de Cirurgia Plástica , Criança , Prepúcio do Pênis/cirurgia , Humanos , Lactente , Masculino , Pênis/cirurgia , Estudos Retrospectivos , Procedimentos Cirúrgicos Urológicos MasculinosRESUMO
We reported an electro-optically cavity-dumped Q-switched Er:Yb:YAl3(BO3)4 pulse laser for the first time. A 1531.1 nm pulse laser with an average output power of 521 mW, energy of 10 µJ, and a duration of 3.1 ns was achieved at a repetition rate of 100 kHz under the quasi-continuous-wave pumping. The pulse characteristics of the laser were investigated in detail. The result shows that the depolarization effects and the length of high voltage (HV) time applied to the EO-switch had significant impacts on the pulse characteristics.