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Abstract Lasing threshold in the conventional lasers is the minimum input power required to initiate laser oscillation. It has been widely accepted that the conventional laser threshold occurring around a unity intracavity photon number can be eliminated in the input-output curve by making the so-called β parameter approach unity. The recent experiments, however, have revealed that even in this case the photon statistics still undergo a transition from coherent to thermal statistics when the intracavity mean photon number is decreased below unity. Since the coherent output is only available above the diminished threshold, the long-sought promise of thresholdless lasers to produce always coherent light has become questionable. Here, we present an always-coherent thresholdless laser based on superradiance by two-level atoms in a quantum superposition state with the same phase traversing a high-Q cavity. Superradiant lasing was observed without the conventional lasing threshold around the unity photon number and the photon statistics remained near coherent even below it. The coherence was improved by reducing the coupling constant as well as the excited-state amplitude in the superposition state. Our results pave a way toward always-coherent thresholdless lasers with more practical media such as quantum dots, nitrogen-vacancy centers and doped ions in crystals.

The percentage of energy consumed by buildings is very large in industry. Recently, the cases of applying smart technology to efficiently improve the energy waste of these buildings are increasing, and this study targets Electrochromic (EC) smart windows. Smart window means a window that can freely change Visible Light Transmittance (VLT) and Solar Heat Gain Coefficient (SHGC). Since windows are the largest medium that can cause energy loss in buildings, the application of smart windows enables efficient energy management. However, this technology currently has a high-cost problem, so a partial application to windows is proposed. This study aims to analyze the relationship between partially applied smart windows and energy loads. Smart windows require an environment control strategy because windows are primarily to provide a comfortable indoor environment. An environmental control strategy was established according to the application area of the smart window, and Useful Daylight Illuminance (UDI) was used. In addition, the energy load of the smart window in which the environmental control strategy was established was derived, and the relationship with the partially applied area was analyzed. This study provides information on how much the partial application of smart windows can save energy wastage in buildings.

Abstract Patients with stroke may develop hyperperfusion after a successful endovascular thrombectomy (EVT). However, the relationship between post-EVT hyperperfusion and clinical outcomes remains unclear and requires further clarification. We reviewed consecutive patients with anterior circulation occlusion who were successfully recanalized with EVT. Based on post-EVT arterial spin-labeling images, hyperperfusion was categorized as follows: global hyperperfusion (GHP), increased cerebral blood flow (CBF) in ≥ 50% of the culprit vessel territory; focal hyperperfusion (FHP), increased CBF in

This study explores Korean pre-service teachers' perceptions, attitudes, and satisfaction with flipped learning courses in a teacher education program. A mixed research method was used to collect the end-of-semester survey (n=62) and individual interview data (n=4). Guided by the four pillars of flipped learning (FL), study results are followed. First, Korean pre-service teachers believed that flipped learning format provided a flexible learning environment where pre-service teachers (PSTs) learn course materials in their own space. This result indicated that their learning happened without the limits of time and space. Second, pre-service teachers showed that their self-directed learning could be enhanced while watching pre-recorded videos before attending the class. Most PSTs agreed that their self-directed learning could be enhanced after participating in the flipped learning courses. Third, pre-service teachers evaluated that the FL course instructor was a professional educator who conveyed the intentional content effectively. Fourth, pre-service teachers were generally satisfied with the FL courses and were willing to take the FL courses again in the future.

Abstract Background Oral ulcers are a common side effect of chemotherapy and affect patients’ quality of life. While stem cell transplantation is a potential treatment for oral ulcers, its efficacy is limited as the stem cells tend to remain in the affected area for a short time. This study aims to develop a treatment for oral ulcers by using trimethyl chitosan (TMC) hydrogel with human tonsil-derived stem cells (hTMSCs) to increase the therapeutic effect of stem cells and investigate their effectiveness. Methods Animals were divided into four experimental groups: Control, TMC hydrogel, hTMSCs, and hTMSCs loaded in TMC hydrogel (Hydrogel + hTMSCs) (each n = 8). Oral ulcers were chemically induced by anesthetizing the rats followed by injection of dilute acetic acid in the right buccal mucosa. After confirming the presence of oral ulcers in the animals, a single subcutaneous injection of 100 µL of each treatment was applied to the ulcer area. Histological analyses were performed to measure inflammatory cells, oral mucosal thickness, and fibrosis levels. The expression level of inflammatory cytokines was also measured using RT-PCR to gauge therapeutic the effect. Results The ulcer size was significantly reduced in the TMC hydrogel + hTMSCs group compared to the control group. The stem cells in the tissue were only observed until Day 3 in the hTMSCs treated group, while the injected stem cells in the TMC Hydrogel + hTMSCs group were still present until day 7. Cytokine analysis related to the inflammatory response in the tissue confirmed that the TMC Hydrogel + hTMSCs treated group demonstrated superior wound healing compared to other experimental groups. Conclusion This study has shown that the adhesion and viability of current stem cell therapies can be resolved by utilizing a hydrogel prepared with TMC and combining it with hTMSCs. The combined treatment can promote rapid healing of oral cavity wounds by enhancing anti-inflammatory effects and expediting wound healing. Therefore, hTMSC loaded in TMC hydrogel was the most effective wound-healing approach among all four treatment groups prolonging stem cell survival. However, further research is necessary to minimize the initial inflammatory response of biomaterials and assess the safety and long-term effects for potential clinical applications.

Abstract Soil microorganisms with diverse bioactive compounds such as Streptomyces are appreciated as valuable resources for the discovery of eco-friendly fungicides. This study isolated a novel Streptomyces from soil samples collected in the organic green tea fields in South Korea. The isolation process involved antifungal activity screening around 2400 culture extracts, revealing a strain designated as S. collinus Inha504 with remarkable antifungal activity against diverse phytopathogenic fungi. S. collinus Inha504 not only inhibited seven phytopathogenic fungi including Fusarium oxysporum and Aspergillus niger in bioassays and but also showed a control effect against F. oxysporum infected red pepper, strawberry, and tomato in the in vivo pot test. Genome mining of S. collinus Inha504 revealed the presence of the biosynthetic gene cluster (BGC) in the chromosome encoding a polyene macrolide which is highly homologous to the lucensomycin (LCM), a compound known for effective in crop disease control. Through genetic confirmation and bioassays, the antifungal activity of S. collinus Inha504 was attributed to the presence of LCM BGC in the chromosome. These results could serve as an effective strategy to select novel Streptomyces strains with valuable biological activity through bioassay-based screening and identify biosynthetic gene clusters responsible for the metabolites using genome mining approach.

Background and Objective This study aimed to assess the effectiveness of acoustic pharyngometry by examining the data before and after adenotonsillectomy in children with sleep-disordered breathing (SDB). Methods This prospective, observational study included 29 children (M/F = 17/12, age = 8.69 ± 2.52 years) with SDB who underwent acoustic pharyngometry before and after adenotonsillectomy. Pre- and postoperative acoustic pharyngometry data, such as the oropharyngeal junction area (OPJ), pharyngeal volume (Vp), glottic area (GL), maximal pharyngeal cross-sectional area (Apmax), minimal pharyngeal cross-sectional area (Apmin), and mean pharyngeal cross-sectional area (Apmean), were compared. Results Before surgery, Apmean was measured at 1.75 ± 0.81 cm2 and increased to 2.24 ± 0.89 cm2 after surgery (p < 0.001); this difference was statistically significant. Moreover, OPJ demonstrated statistically significant changes from 1.03 ± 0.62 cm2 to 1.53 ± 0.77 cm2 (p < 0.001); Apmin measured from 0.99 ± 0.51 cm2 to 1.38 ± 0.69 cm2 (p = 0.003); and Vp increased from 14.45 ± 7.05 cm3 to 18.89 ± 7.72 cm3 (p < 0.001) after surgical treatment. Conclusions Acoustic pharyngometry, a non-invasive and reproducible method, effectively reflects upper airway changes before and after adenotonsillectomy in children with SDB and ATH. This underscores its potential as a valuable tool for objectively evaluating upper airway obstruction caused by ATH in children.

Abstract The advanced patterning process is the basis of integration technology to realize the development of next-generation high-speed, low-power consumption devices. Recently, area-selective atomic layer deposition (AS-ALD), which allows the direct deposition of target materials on the desired area using a deposition barrier, has emerged as an alternative patterning process. However, the AS-ALD process remains challenging to use for the improvement of patterning resolution and selectivity. In this study, we report a superlattice-based AS-ALD (SAS-ALD) process using a two-dimensional (2D) MoS2-MoSe2 lateral superlattice as a pre-defining template. We achieved a minimum half pitch size of a sub-10 nm scale for the resulting AS-ALD on the 2D superlattice template by controlling the duration time of chemical vapor deposition (CVD) precursors. SAS-ALD introduces a mechanism that enables selectivity through the adsorption and diffusion processes of ALD precursors, distinctly different from conventional AS-ALD method. This technique facilitates selective deposition even on small pattern sizes and is compatible with the use of highly reactive precursors like trimethyl aluminum. Moreover, it allows for the selective deposition of a variety of materials, including Al2O3, HfO2, Ru, Te, and Sb2Se3.

Objectives. This study aimed to compare the oncological outcomes of partial versus superficial or total parotidectomy for superficial T1 or T2 primary parotid cancers and investigate their prognostic factors and recurrence patterns. Methods. The medical records of 77 patients with T1–2 primary parotid malignancies between May 2003 and March 2022 were retrospectively reviewed. Univariate and multivariate analyses were performed to evaluate the prognostic factors associated with overall survival, disease-free survival, and local and distant recurrence. Results. The average follow-up duration was 70.2 months (range, 12–202 months). The 5-year overall and disease-free survival rates were 88.7% and 77.1%, respectively. Twenty-two patients underwent partial parotidectomy, and 55 underwent superficial or total parotidectomy. There were no significant differences in the disease recurrence (P=0.320) and mortality rates (P=0.884) of the partial and superficial or total parotidectomy groups. The mean duration of surgery was shorter and the overall complication rates were significantly lower in the partial group than in the superficial or total parotidectomy group (P=0.049). Sixteen cases of recurrence occurred during the study period (20.8%). Univariate analyses showed that high-grade tumors (P=0.006), lymphovascular invasion (P=0.046), and regional lymph node metastasis (P=0.010) were significant risk factors for disease recurrence. Multivariate analysis identified regional lymph node metastasis as an independent prognostic factor for disease recurrence (P=0.027), and lymphovascular invasion as an independent prognostic factor for overall survival (P=0.033). Conclusion. The conservative surgical approach of partial parotidectomy can yield oncological outcomes comparable to those of superficial or total parotidectomy with careful patient selection in T1-2 parotid cancers.

This study introduces a new approach in Korean morphological analysis combining dictionary-based techniques with Transformer-based deep learning models. The key innovation is the use of a BERT-based reranking system, significantly enhancing the accuracy of traditional morphological analysis. The method generates multiple suboptimal paths, then employs BERT models for reranking, leveraging their advanced language comprehension. Results show remarkable performance improvements, with the first-stage reranking achieving over 20% improvement in error reduction rate compared with existing models. The second stage, using another BERT variant, further increases this improvement to over 30%. This indicates a significant leap in accuracy, validating the effectiveness of merging dictionary-based analysis with contemporary deep learning. The study suggests future exploration in refined integrations of dictionary and deep learning methods as well as using probabilistic models for enhanced morphological analysis. This hybrid approach sets a new benchmark in the field and offers insights for similar challenges in language processing applications.

We propose a method to automatically predict Alzheimer’s disease from speech data using the ChatGPT large language model. Alzheimer’s disease patients often exhibit distinctive characteristics when describing images, such as difficulties in recalling words, grammar errors, repetitive language, and incoherent narratives. For prediction, we initially employ a speech recognition system to transcribe participants’ speech into text. We then gather opinions by inputting the transcribed text into ChatGPT as well as a prompt designed to solicit fluency evaluations. Subsequently, we extract embeddings from the speech, text, and opinions by the pretrained models. Finally, we use a classifier consisting of transformer blocks and linear layers to identify participants with this type of dementia. Experiments are conducted using the extensively used ADReSSo dataset. The results yield a maximum accuracy of 87.3% when speech, text, and opinions are used in conjunction. This finding suggests the potential of leveraging evaluation feedback from language models to address challenges in Alzheimer’s disease recognition.

In this paper, a new Complete Coverage Path Planning (CCPP) scheme is proposed which combines path planning and dynamic tracking for robot operating system-based robots. For the path planning, firstly a sub-area division algorithm is considered to decompose the occupancy map according to the wall or obstacle position after simultaneous localization and mapping process. For each sub-area, an “S” shape path planning is employed, and then a Bidirectional A-star connects them. Additionally, the dynamic tracking ensures that the robot moves continuously. Simulation results show that the coverage ratio of the planning path is improved as 98% by the proposed scheme.