High-power and high-efficiency operation of 1.3 µm-wavelength InP-based photonic-crystal surface-emitting lasers with metal reflector.

We demonstrate high-output-power and high-efficiency operation of 1.3-µm-wavelength InP-based photonic-crystal surface-emitting lasers (PCSELs). By introducing a metal reflector and adjusting the phase of the reflected light via optimization of the thickness of the p-InP cladding layer, we successfully achieve an output power of approximately 400 mW with the slope efficiency of 0.4 W/A and the wall-plug efficiency of 20% under CW conditions. In addition, this PCSEL exhibits a narrow circular beam with a divergence angle below 1.6° even at high output powers under CW conditions at temperatures from 15°C to 50°C. We have also demonstrated an output power of over 12 W under pulsed conditions at room temperature.

Bayesian design of mosaic-based mode multiplexers for various wavelength bands.

Ultracompact mode multiplexers based on mosaic structure for various wavelength bands designed by Bayesian technique are investigated. C-, O-, and C + O band, TE0-TE1 2-mode multiplexers can be designed with the same footprint, by only changing the mosaic-pattern, showing the great flexibility of mosaic-based devices. Bayesian direct binary search method is used for the design, and it is demonstrated that the Bayesian technique is superior to conventional design method in terms of the best-structure search for the same number of iterations. The designed devices are fabricated for Si-waveguide platform, and the proof-of-concept results are obtained. These results indicate that the mosaic-based devices are promising candidates for future compact optical transceivers.

Pre-Extubation Cuffed Tube Leak Test and Subsequent Post-Extubation Laryngeal Edema: Prospective, Single-Center Evaluation of PICU Patients.

OBJECTIVES: We performed our standard air leak, leak percentage, and cuff leak percentage tests in pediatric patients intubated with microcuff pediatric tracheal tubes (MPTTs) just before extubation. We examined the association between test findings and the subsequent occurrence of post-extubation laryngeal edema (PLE). DESIGN: Prospective, single-center, observational study. SETTING: PICU (June 1, 2020 to May 31, 2021). PATIENTS: Pediatric patients intubated and scheduled for extubation during the day shift in the PICU. INTERVENTIONS: Multiple pre-extubation leak tests were performed on each patient immediately before extubation. In our center, the standard leak test is positive if a leak is audible at 30 cm H 2 O applied pressure with the MPTT cuff deflated. Two other tests were calculated in the pressure control-assist control ventilator mode using the following formulas: leak percentage with deflated cuff = (inspiratory tidal volume [V t ]-expiratory V t ) × 100/inspiratory V t ; cuff leak percentage = (expiratory V t with inflated cuff-expiratory V t with deflated cuff) × 100/expiratory V t with inflated cuff. MEASUREMENTS AND MAIN RESULTS: The diagnostic criteria for PLE was made by at least two healthcare professionals and included upper airway stricture with stridor-requiring nebulized epinephrine. Eighty-five pediatric patients (< 15 yr) who had been intubated for at least 12 hours using the MPTT were included. Positive rates for the standard leak, leak percentage (cutoff 10%), and cuff leak percentage (cutoff 10%) tests were 0.27, 0.20, and 0.64, respectively. The standard leak, leak percentage, and cuff leak tests showed sensitivities of 0.36, 0.27, and 0.55, respectively; and specificities of 0.74, 0.81, and 0.35, respectively. PLE occurred in 11 of 85 patients (13%), and there were no instances of needing reintubation. CONCLUSIONS: The pre-extubation leak tests in current practice for intubated pediatric patients in the PICU all lack diagnostic accuracy for PLE.

High-power CW oscillation of 1.3-µm wavelength InP-based photonic-crystal surface-emitting lasers.

We demonstrate high-power continuous-wave (CW) lasing oscillation of 1.3-µm wavelength InP-based photonic-crystal surface-emitting lasers (PCSELs). Single-mode operation with an output power of over 100 mW, a side-mode suppression ratio (SMSR) of over 50 dB, and a narrow single-lobe beam with a divergence angle of below 1.2° are successfully achieved by using a double-lattice photonic crystal structure consisting of high-aspect-ratio deep air holes. The double lattice is designed to enhance both the in-plane optical feedback and the surface radiation effects in the photonic crystal. The coupling coefficients for 180 ∘, +90 ∘, and -90 ∘ diffractions are estimated from the measurements of the photonic band structure as κ1D = 417 cm-1, κ2D+ = 135 cm-1, and κ2D- = 65 cm-1, respectively. The stable single-mode, high-beam-quality operation is attributed to these large coupling coefficients introduced by the asymmetric double-lattice structure.

Physical Restraints in Critically Ill Children: A Multicenter Longitudinal Point Prevalence Study.

OBJECTIVES: We elucidate to investigate the prevalence of and factors associated with the use of physical restraints among critically ill or injured children in PICUs. DESIGN: This was a multicenter, longitudinal point prevalence study. SETTING: We included 26 PICUs in Japan. PATIENTS: Included children were 1 month to 10 years old. We screened all admitted patients in the PICUs on three study dates (in March, June, and September 2019). INTERVENTION: None. MEASUREMENTS AND MAIN RESULTS: We collected prevalence and demographic characteristics of critically ill or injured children with physical restraints, as well as details of physical restraints, including indications and treatments provided. A total of 398 children were screened in the participating PICUs on the three data collection dates. The prevalence of children with physical restraints was 53% (211/398). Wrist restraint bands were the most frequently used means (55%, 117/211) for potential contingent events. The adjusted odds of using physical restraint in patients 1-2 years old was 2.3 (95% CI, 1.3-4.0) compared with children less than 1 year old. When looking at the individual hospital effect, units without a prespecified practice policy for physical restraints management or those with more than 10 beds were more likely to use physical restraints. CONCLUSIONS: The prevalence of physical restraints in critically ill or injured children was high, and significant variation was observed among PICUs. Our study findings suggested that patient age, unit size, and practice policy of physical restraint could be associated with more frequent use of physical restraints.

Quasi-continuous tuning of a 1.3-µm-wavelength superstructure grating distributed Bragg reflector laser by enhancing carrier-induced refractive index change.

To overcome the limitation of the small tuning range of 1.3-µm-wavelength distributed Bragg reflector (DBR) lasers using the carrier-plasma effect, we designed a DBR structure with InAlAs carrier confinement layers and an InGaAlAs core layer. We found that the enhanced carrier density and small effective mass of electrons in the core layer of the DBR regions resulted in a wide Bragg wavelength shift. The enhanced refractive-index change due to the new structure enabled us to fabricate the world's first 1.3-µm-wavelength superstructure-grating DBR laser with a quasi-continuous tuning range of over 30 nm.

[EFFECTIVENESS OF ADD-ON SUBLINGUAL IMMUNOTHERAPY FOR THE TREATMENT OF JAPANESE CEDAR POLLINOSIS-ASSOCIATED ALLERGIC ASTHMA IS IT POSSIBLE TO REDUCE THE DOSE OF INHALED CORTICOSTEROID BY ADDING SUBLINGUAL IMMUNOTHERAPY?]

BACKGROUND: This study investigated the effect of adjuvant sublingual immunotherapy (SLIT) on inhaled corticosteroid (ICS) dose in patients with pollinosis-associated asthma. METHODS: We retrospectively evaluated patients with cedar pollinosis-associated asthma who initiated pharmacotherapy with or without adjuvant SLIT therapy from December 2014 to December 2016 and who continued treatment for 3 years. Changes in ICS dose (fluticasone propionate or its equivalent), antihistamine use, leukotriene antagonist use and intranasal corticosteroid (INCS) use over the 3-year period were compared. RESULTS: The study included 36 and 35 patients in the add-on SLIT and standard treatment groups, respectively. At 3 years, the add-on SLIT group showed a significant decline in ICS dose (p = 0.024). Although leukotriene antagonist use and INCS use did not differ between the two groups, the percentage of patients using antihistamines at 3 years was significantly lower in the add-on SLIT group than in the standard treatment group (p = 0.009); one in three patients on adjuvant SLIT therapy was able to discontinue ICS treatment. Patients who discontinued ICS treatment were younger (44.6±13.3 years vs. 55.0±14.1 years, p = 0.042), had a higher FEV1% predicted (109.9±14.4 vs. 94.8±18.6, p = 0.02), and were on a lower treatment step (2.1±0.7 vs. 3.0±0.8, p = 0.002) than those who did not. CONCLUSION: The addition of SLIT to standard pharmacotherapy resulted in a significant reduction in ICS dose at 3 years.

Inter-layer light transition in hybrid III-V/Si waveguides integrated by µ-transfer printing.

We demonstrate low-loss and broadband light transition from III-V functional layers to a Si platform via two-stage adiabatic-crossing coupler waveguides. A 900-µm-long and 2.7-µm-thick III-V film waveguide consisting of a GaInAsP core and InP cladding layers is transferred onto an air-cladding Si photonic chip by the µ-transfer printing (µ-TP) method. An average optical coupling loss per joint of 1.26 dB is obtained in C + L telecommunication bands (1530-1635 nm). The correlation between alignment offset and measured optical coupling loss is discussed with the frequency distribution of µ-TP samples. We also performed a photoluminescence measurement to investigate the material properties in the GaInAsP layer to see if they are distorted by the strong bending stress produced during the pick-up and print steps of the µ-TP process. The peak intensity reduction of 80-90% and a wavelength shift of 0-5 nm (blue shift) were observed after the process. The series of fundamental studies presented here, which combine multiple analyses, contribute to improving our understanding of III-V/Si photonic integration by µ-TP.

Continous-wave lasing operation of 1.3-µm wavelength InP-based photonic crystal surface-emitting lasers using MOVPE regrowth.

We report on electrically driven InP-based photonic-crystal surface-emitting lasers (PCSELs), which possess a deep-air-hole photonic crystal (PC) structure underneath an active region formed by metal-organic vapor-phase-epitaxial (MOVPE) regrowth. Single-mode continuous-wave (CW) lasing operation in 1.3-µm wavelength is successfully achieved at a temperature of 15°C. It is shown that the enhancement of lateral growth during the MOVPE regrowth process of air holes enables the formation of deep air holes with an atomically flat and thin overlayer, whose thickness is less than 100 nm. A threshold current of 120 mA (threshold current density = 0.68 kA/cm2) is obtained in a device with a diameter of 150 µm. A doughnut-like far-field pattern with the narrow beam divergence of less than 1° is observed. Strong optical confinement in the PC structure is revealed from measurements of the photonic band structure, and this strong optical confinement leads to the single-mode CW lasing operation with a low threshold current density.

Enhanced Fourier-transform method for high-density fringe analysis by iterative spectrum narrowing.

We propose a model-based fringe analysis technique that enables the Fourier transform method to analyze dense fringe patterns with large phase variations. The conventional Fourier-transform method has a limited dynamic range of measurable phase because the Fourier spectra broadened by large phase variations cannot be separated by the spatial carrier frequency. Our model-based iterative technique effectively narrows the broad spectrum and reduces phase errors. Results of simulations and experiments are presented that demonstrate the validity of the proposed spectrum-narrowing technique for high-density fringe patterns.

Harmine promotes molar root development via SMAD1/5/8 phosphorylation.

Tooth and bone are major tissues involved in physiological calcification in the body, and they use similar molecular pathways for development, homeostasis, and regeneration. Harmine (HMN) is a natural small compound that stimulates osteoblast differentiation in vitro and in vivo. Here we examined the biological effect of HMN on the postnatal development of molar tooth roots and periodontal tissues. HMN supported the formation of tooth roots and periodontal tissues in developing tooth germs. In tooth germ organ culture, HMN promoted the elongation of Hertwig's epithelial root sheath (HERS) and stimulated cell proliferation in HERS and dental follicle-derived tissues, including dental papillae and dental follicles. HMN stimulated cell proliferation and cell movement of HERS-derived cells without mesenchymal cells in vitro and directly induced the phosphorylation of SMAD1/5/8 protein in HERS-derived cells. Our results indicated that HMN was the first natural small compound to stimulate postnatal development of tooth germs.

Pathogenesis of primordial odontogenic tumour based on tumourigenesis and odontogenesis.

OBJECTIVE: Primordial odontogenic tumour (POT) is a rare benign mixed epithelial and mesenchymal odontogenic tumour. POT is composed of dental papilla-like tissue covered with cuboidal to columnar epithelium that resembles to inner and outer enamel epithelium of the enamel organ without dental hard tissue formation. The aim of this study was to examine pathogenesis of POT based on tumourigenesis and odontogenesis. SUBJECTS AND METHODS: Six cases of POT were submitted for study. DNA analysis and transcriptome analysis were performed by next-generation sequencing. Expression of amelogenin, ameloblastin and dentin sialophosphoprotein (DSPP) was examined by immunohistochemistry. RESULTS: There were no gene mutations detected in any of analysed 151 cancer- and 42 odontogenesis-associated genes. Enamel protein-coding genes of Amelx, Ambn and Enam, and dentin protein-coding genes of Col1a1, Dspp, Nes and Dmp1 were expressed, whereas expression of dentinogenesis-associated genes of Bglap, Ibsp and Nfic was negative or very weak suggesting inhibition of dentin formation in POT after odontoblast differentiation. Immunoreactivity of amelogenin, ameloblastin and DSPP was detected in POT. CONCLUSIONS: Pathogenesis of POT is considered to be genetically different from other odontogenic tumours. It is suggested that inhibition of enamel and dentin formation in POT is due to defects in dentin formation process.

Primordial Odontogenic Tumor: A case report with histopathological analyses.

Primordial odontogenic tumor (POT) is a benign mixed epithelial and mesenchymal odontogenic tumor included into the current World Health Organization (WHO) classification of Head and Neck tumours in 2017. As far as the authors have confirmed, only eight cases of this tumor have been reported so far. This paper reports a case of POT that occurred in the right mandible of a 5-year-old patient. Panoramic radiograph showed a well-defined homogeneous radiolucency displacing the unerupted second deciduous molar to the deep part of the mandible. Histopathologically, the tumor was composed of cell-rich mesenchymal tissue with myxoid areas, surrounded by columnar epithelium and non-keratinized cuboidal epithelium in the outer layers. The histopathological diagnosis was POT. The expression patterns of cytokeratins (CK) 14, 18, 19, vimentin and CD34 suggested that the grade of differentiation of the POT was approximately equivalent to that of normal primary tooth germ tissues in cap stage to late bell stage.

Development of myelofibrosis during eltrombopag treatment in a patient with immune thrombocytopenia.

Eltrombopag, a thrombopoietin (TPO) receptor agonist, is effective for treating refractory immune thrombocytopenia (ITP). However, the development of bone marrow fibrosis is a concern. A 78-year-old man was diagnosed with ITP in 2004. His platelet count did not increase after eltrombopag treatment initiation in 2014. However, anemia progressed, along with the presence of immature myelocytes, erythroblasts, and tear drop cells. At 8 months after initiating eltrombopag treatment, the patient underwent a bone marrow biopsy that showed grade 2 myelofibrosis. Hence, eltrombopag was discontinued. In our experience with this case indicates that careful observation is required while using TPO receptor agonists.

Regulatory mechanisms of Hertwig׳s epithelial root sheath formation and anomaly correlated with root length.

Teeth are composed of two domains, the enamel-covered crown and cementum-covered root. The mechanism for determining the transition from crown to root is important for understanding root anomaly diseases. Hertwig׳s epithelial root sheath (HERS) is derived from the dental epithelium and is known to drive the growth of root dentin and periodontal tissue. Some clinical cases of hypoplastic tooth root are caused by the cessation of HERS development. Understanding the mechanisms of HERS development will contribute to the study of the disease and dental regenerative medicine. However, the developmental biology of tooth root formation has not been fully studied, particularly regarding HERS formation. Here, we describe the mechanisms of HERS formation on the basis of analysis of cell dynamics using imaging and summarize how the growth factor and its receptor regulate cell behavior of the dental epithelium.

Feasibility and perceptions of a benzodiazepine deprescribing quality improvement initiative for primary care providers in Japan.

BACKGROUND: Quality improvement (QI) initiatives in primary care in Japan are rare. One crucial area for QI is the appropriate prescription of benzodiazepines due to the large and growing elderly population in the country. OBJECTIVE: This study aimed to determine the feasibility and other perceptions of a Benzodiazepine receptor agonist medications (BZRAs) deprescribing QI initiative for primary care providers (PCPs) in Japanese primary care clinics. DESIGN: A qualitative study within a QI initiative. PARTICIPANTS: We recruited 11 semi-public clinics and 13 providers in Japan to participate in a BZRAs deprescribing initiative from 2020 to 2021. After stratifying the clinics according to size, we randomly allocated implementation clinics to either an Audit only or an Audit plus Coaching group. INTERVENTIONS: For the Audit, we presented clinics with two BZRAs-related indicators. We provided monthly web-based meetings for the Coaching to support their QI activities. APPROACH: After the nine-month initiative, we conducted semi-structured interviews and used content analysis to identify themes. We organized the themes and assessed the key factors of implementation using the Consolidated Framework for Implementation Research (CFIR) framework. KEY RESULTS: Audit plus Coaching was perceived as more valuable than Audit only intervention. Participants expressed intellectual curiosity about the QI initiative from resources outside their clinic. However, adopting a team-based QI approach in a small clinic was perceived as challenging, and selecting the indicators was important for meaningful QI. CONCLUSION: The small size of the clinic could be a potential barrier, but enhancing academic curiosity may facilitate QI initiatives in primary care in Japan. Further implementation trials are needed to evaluate the possibility of QI with more various indicators and a more extended period of time.