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1.
Cancer Res Treat ; 2024 May 10.
Article in English | MEDLINE | ID: mdl-38754473

ABSTRACT

Purpose: Triple-negative breast cancer (TNBC) is a particularly challenging subtype of breast cancer, with a poorer prognosis compared to other subtypes. Unfortunately, unlike luminal type cancers, there is no validated biomarker to predict the prognosis of patients with early-stage TNBC. Accurate biomarkers are needed to establish effective therapeutic strategies. Materials and Methods: In this study, we analyzed gene expression profiles of tumor samples from 184 TNBC patients (training cohort, n=76; validation cohort, n=108) using RNA sequencing. Results: By combining weighted gene expression, we identified a 10-gene signature (DGKH, GADD45B, KLF7, LYST, NR6A1, PYCARD, ROBO1, SLC22A20P, SLC24A3, and SLC45A4) that stratified patients by risk score with high sensitivity (92.31%), specificity (92.06%), and accuracy (92.11%) for invasive disease-free survival. The 10-gene signature was validated in a separate institution cohort and supported by meta-analysis for biological relevance to well-known driving pathways in TNBC. Furthermore, the 10-gene signature was the only independent factor for invasive disease-free survival in multivariate analysis when compared to other potential biomarkers of TNBC molecular subtypes and T-cell receptor ß diversity. 10-gene signature also further categorized patients classified as molecular subtypes according to risk scores. Conclusion: Our novel findings may help address the prognostic challenges in TNBC and the 10-gene signature could serve as a novel biomarker for risk-based patient care.

2.
Article in English | MEDLINE | ID: mdl-38750786

ABSTRACT

BACKGROUND: Bone marrow stimulation (BMS), a procedure involving the creation of multiple channels in the greater tuberosity, is often performed alongside arthroscopic rotator cuff repair (ARCR). This study evaluated the effect of BMS on clinical and structural outcomes following ARCR. METHOD: This study involved 204 patients with small, medium, and large full-thickness rotator cuff tears. In all, 103 patients who underwent BMS and ARCR made up the BMS group, while the 101 patients who only had ARCR made up the control group with randomization. Clinical and functional outcomes were assessed before and at 3 months, 6 months, 1 year, and 2 years after surgery, using parameters such as range of motion, functional scores (ASES and constant score), and clinical scores (VAS). Tendon integrity was also examined postoperatively via ultrasound at 6 months and 2 years. RESULTS: There were no significant differences between the two groups concerning range of motion, functional scores (ASES score and constant score), and clinical score (VAS) during the 2-year post-surgery period (all p>0.05). Similarly, the rotator cuff retear rate, as assessed using ultrasonographic tendon integrity checks over 2 years post-surgery, did not significantly vary between the groups (all p>0.05). CONCLUSION: There were no significant disparities in functional scores and clinical outcomes between the BMS and control groups. Further, no significant differences were observed in tendon integrity post-surgery. Therefore, the inclusion or exclusion of BMS is not anticipated to influence the postoperative outcome in ARCR for patients with small, medium, or large rotator cuff tears.

3.
Helicobacter ; 29(3): e13096, 2024.
Article in English | MEDLINE | ID: mdl-38790093

ABSTRACT

BACKGROUND: Helicobacter pylori (H. pylori) is a common bacterial infection which predominately drives upper gastrointestinal pathology. We carried out a nationwide serological survey in response to the deficiency of robust African data on H. pylori prevalence, age of acquisition, socio-geographic determinants, and impact on gastric physiology. MATERIALS AND METHODS: This was a cross-sectional study of archival plasma samples collected during the Zambia Population-based HIV impact Assessment (ZAMPHIA) 2016 survey. ZAMPHIA used a two-stage door-to-door stratified cluster sample approach to collect samples from adults and children from age 0 to 59 years (n = 24,266). We randomly retrieved one fifth of these samples from each of Zambia's 10 provinces and used ELISA to test for H. pylori IgG antibodies, pepsinogen 1 and 2 and gastrin-17. A pepsinogen 1:2 ratio of <3 was used to define gastric atrophy. RESULTS: The analysis of 4050 plasma samples (30% <16 years, 53% females) revealed an overall H. pylori seroprevalence of 79%. By the age of 10 years, more than 75% of the children had H. pylori. Urban residence was associated with increased odds (OR 1.8, 95% CI 1.5-2.2, p < 0.001) and HIV infection was associated with reduced odds (OR 0.7, 95% CI 0.5-0.9, p = 0.02) of H. pylori seropositivity. Gastric atrophy was detected in 6% of H. pylori seropositive adults below 45 years of age and 9% in those between 45 and 59 years. CONCLUSIONS: We have confirmed a high prevalence of H. pylori seropositivity in Zambia, predominantly in urban settings. The prevalence of gastric atrophy is broadly consistent with other populations around the globe, but our sample did not include adults over 60 years.


Subject(s)
Antibodies, Bacterial , Helicobacter Infections , Helicobacter pylori , Humans , Zambia/epidemiology , Helicobacter Infections/epidemiology , Helicobacter Infections/microbiology , Female , Male , Adult , Cross-Sectional Studies , Adolescent , Middle Aged , Young Adult , Helicobacter pylori/isolation & purification , Helicobacter pylori/immunology , Child , Child, Preschool , Antibodies, Bacterial/blood , Seroepidemiologic Studies , Infant , Prevalence , Infant, Newborn , Immunoglobulin G/blood , Gastritis, Atrophic/epidemiology , Gastritis, Atrophic/microbiology
4.
Yonsei Med J ; 65(6): 341-347, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38804028

ABSTRACT

PURPOSE: Repeated transcranial direct current stimulation (tDCS) is expected to have the potential to improve cognitive function in patients with mild cognitive impairment (MCI). We aimed to evaluate the efficacy and safety of at-home tDCS for elderly patients with MCI. MATERIALS AND METHODS: Patients aged 60-80 years, who maintained normal daily living but reported objective memory impairments, were enrolled. Active or sham stimulations were applied to the dorsal frontal cortex (left: anode; right: cathode) at home for 2 weeks. Changes in cognitive function were assessed using visual recognition tasks and the Mini-Mental State Exam (MMSE), and safety and efficacy were assessed using self-reports and a remote monitoring application. RESULTS: Of the 19 participants enrolled, 12 participants were included in the efficacy analysis. Response times and MMSE scores significantly improved after active stimulation compared to the sham stimulation; however, there were no significant differences in the proportion of correct responses. The mean compliance of the efficacy group was 97.5%±4.1%. Three participants experienced burns, but no permanent sequelae remained. CONCLUSION: This preliminary result suggests that home-based tDCS may be a promising treatment option for MCI patients; however, it requires more attention and technological development to address safety concerns. CLINICAL TRIAL REGISTRATION: Clinical Research Information Service (CRIS), KCT0002721.


Subject(s)
Cognition , Cognitive Dysfunction , Transcranial Direct Current Stimulation , Aged , Aged, 80 and over , Female , Humans , Male , Middle Aged , Cognition/physiology , Cognitive Dysfunction/therapy , Transcranial Direct Current Stimulation/methods , Treatment Outcome
5.
Nanoscale ; 16(21): 10292-10305, 2024 May 30.
Article in English | MEDLINE | ID: mdl-38721842

ABSTRACT

Barium molybdate nanoparticles exhibiting up-conversion luminescence were synthesized via the solvothermal method. Analysis revealed a prominent signal corresponding to the (112) plane in the XRD pattern, indicating the tetragonal structure of the synthesized nanoparticles. Raman spectroscopy detected the symmetric stretching frequencies of MoO4. When excited at 980 nm, the nanoparticles emitted a green spectrum with peaks at 532 and 553 nm. The luminescence intensity varied with the excitation light source, supporting the mechanism involving energy transfer from Yb-doped Er ions via the two-photon effect of the up-conversion phosphor. Moreover, the synthesized nanoparticles exhibited diminished luminous intensity with increasing temperature, suggesting potential for flexible composite sensor fabrication. Integration with a 980 nm LED chip yielded a green emission color. Furthermore, when applied to banknotes, plastic cards, fabrics, and artwork, the opaque solution mixed with polymers remained invisible to the naked eye; however, under 980 nm laser irradiation, the distinct green color became apparent, offering a viable approach for anti-counterfeiting measures.

6.
Int J Periodontics Restorative Dent ; 44(3): 299-307, 2024 05 24.
Article in English | MEDLINE | ID: mdl-38787708

ABSTRACT

This study aimed to investigate the dimensional stability and quality of the alveolar ridge augmented using a synthetic bone block (SBB) at damaged extraction sockets. Four participants were included, and socket augmentation was performed using SBB and a collagen membrane. Intraoral and CBCT scans were performed before extraction (baseline), immediately postoperative (IP), and at 6 months postoperative (6M). At 6M, a trephine biopsy sample was obtained during implant placement, and the sample was observed using synchrotron. Soft tissue profile changes were assessed using profilometric analysis of the intraoral scan data, while dimensional changes in hard tissue were evaluated based on CBCT measurements. Bone quality was analyzed using synchrotron imaging. There were minimal changes in the soft tissue profile between baseline and IP, baseline and 6M, and IP and 6M (0.11 ± 1.08 mm3, 0.02 ± 0.8 mm3, and -0.65 ± 0.82 mm3, respectively). Horizontal bone width was measured at 1-mm increments from the augmented bone crest to 5 mm apically and revealed only a slight reduction (< 1 mm) at all levels between IP and 6M. The augmented bone height was well maintained from IP until 6M (-0.21 ± 0.53 mm). Synchrotron analysis revealed low to moderate bone quality after 6M (percentage of new bone: 16.49% ± 4.91%). Socket augmentation using SBB appears to be a viable technique for regenerating damaged extraction sockets, with the augmented ridge dimensions maintained up to 6M. Further long-term randomized clinical trials are needed.


Subject(s)
Alveolar Ridge Augmentation , Cone-Beam Computed Tomography , Synchrotrons , Tooth Socket , Humans , Tooth Socket/surgery , Tooth Socket/diagnostic imaging , Pilot Projects , Alveolar Ridge Augmentation/methods , Middle Aged , Male , Female , Tooth Extraction , Dental Implantation, Endosseous/methods , Adult , Bone Substitutes/therapeutic use , Aged , Collagen/therapeutic use
7.
ACS Omega ; 9(19): 21587-21594, 2024 May 14.
Article in English | MEDLINE | ID: mdl-38764616

ABSTRACT

Transition metal dichalcogenides (TMDs) are promising candidates for ultrathin functional semiconductor devices. In particular, incorporating plasmonic nanoparticles into TMD-based devices enhances the light-matter interaction for increased absorption efficiency and enables control of device performance such as electronic, electrical, and optical properties. In this heterohybrid structure, manipulating the number of TMD layers and the aggregate size of plasmonic nanoparticles is a straightforward approach to tailoring device performance. In this study, we use photoluminescence (PL) spectroscopy, which is a commonly employed technique for monitoring device performance, to analyze the changes in electronic and optical properties depending on the number of MoS2 layers and the size of the gold nanoparticle (AuNP) aggregate under nonresonant and resonant excitation conditions. The PL intensity in monolayer MoS2/AuNPs increases as the size of aggregates increases irrespective of the excitation conditions. The strain induced by AuNPs causes a red shift, but as the aggregates grow larger, the effect of p-doping increases and the blue shift becomes prominent. In multilayer MoS2/AuNPs, quenched PL intensity is observed under nonresonant excitation, while enhancement is noted under resonant excitation, which is mainly contributed by p-doping and LSPR, respectively. Remarkably, the alteration in the spectral shape due to resonant excitation is evident solely in small aggregates of AuNPs across all layers.

8.
J Prosthet Dent ; 2024 May 25.
Article in English | MEDLINE | ID: mdl-38797573

ABSTRACT

STATEMENT OF PROBLEM: Interest is growing in immediately loading definitive implant-supported prostheses. However, it appears that implant protocols are evolving faster than their scientific validation. PURPOSE: The purpose of this scoping review was to identify the current trends, feasibility, and clinical outcomes of a specific clinical loading scenario (type A), where a single definitive implant-retained restoration is delivered within 3 days. The focus question was "In partially edentulous patients requiring an implant-retained prosthesis (population), is immediate loading with a definitive restoration (concept) a viable treatment option (context)?" MATERIAL AND METHODS: An electronic search was conducted in the PubMed, CENTRAL, Scopus, Embase, and Web of Science databases. Two authors independently reviewed the studies, screened titles and abstracts, and performed full-text analysis. Cross-reference checks within the bibliography of included studies, relevant reviews, and guideline were conducted. Bibliometric information and study details were extracted. RESULTS: The search identified 2568 titles after removing duplicates. Four studies involving 91 participant and 100 implant-retained restorations were included in this scoping review. The selected articles were a randomized controlled trial (RCT), a prospective clinical study, and the remaining 2 were case series. The follow-up periods investigated ranged from 6 to 26 months. All studies evaluated marginal bone loss as a primary outcome, and only 1 implant failure was reported. Patient-reported outcome measures were favorable, and no major biological or technical complications were reported in any study. CONCLUSIONS: Immediate loading with a definitive restoration within 3 days appears to be a suitable approach in specific clinical situations.

9.
ACS Appl Mater Interfaces ; 16(13): 16553-16562, 2024 Apr 03.
Article in English | MEDLINE | ID: mdl-38570940

ABSTRACT

In this study, two novel multiple resonance (MR) emitters, DtCzBN and Cy-DtCzBN, were designed based on the well-known BCzBN structure and synthesized for narrowband solution-processed organic light-emitting diodes (OLEDs). Cy-DtCzBN possesses a dimeric V-shaped structure formed by coupling two individual DtCzBN units via a nonconjugated cyclohexane linker. When compared with DtCzBN, Cy-DtCzBN, as a medium-sized molecule, was found to maintain the optical and photophysical properties of the corresponding monomeric unit, DtCzBN, but exhibits high thermal stability, excellent solubility, and good film-forming ability. Additionally, solution-processed OLEDs were fabricated by using two sets of molecules: one set of small molecular hosts and emitters (i.e., mCP and DtCzBN) and the other set of medium-sized molecular hosts and emitters (i.e., Cy-mCP and Cy-DtCzBN). Notably, devices using medium-sized molecular hosts and emitters exhibited similar optical and photophysical properties but showed significantly improved reproducibility and thermal stability compared with those based on small molecular hosts and emitters. Our current study provides some insights into molecular design strategies for thermally stable hosts and emitters, which are highly suitable for solution-processed OLEDs.

10.
J Esthet Restor Dent ; 2024 Apr 09.
Article in English | MEDLINE | ID: mdl-38591169

ABSTRACT

OBJECTIVES: To evaluate clinical, clinician- and patient-reported outcomes (PROs) of two adjacent single posterior implants immediately loaded with definitive single crowns up to 1 year. Ten patients in need of two adjacent posterior single implants were included. All implants were placed applying a fully digital workflow. Definitive screw-retained single zirconia crowns were delivered within 72 h after implant placement. Clinical parameters, patient- and clinician-reported outcomes were assessed up to 1 year of follow-up. CLINICAL CONSIDERATIONS: Clinical outcomes remained stable, with no implant failures or technical and biological complications throughout the observation period. Patient satisfaction was very high at baseline (crown delivery) and remained consistently high at 6 and 12 months of follow-up. Crown insertion 3 days after implant placement was rated as an easy procedure by clinicians. CONCLUSIONS: Two adjacent single implants with immediate definitive restorations (<72 h) in the posterior region appear to be a viable and easy treatment option to shorten the overall treatment time and potentially enhancing patient satisfaction. However, randomized controlled trials are needed to confirm the advantages of this treatment protocol over a delayed loading approach. CLINICAL SIGNIFICANCE: In selected cases, immediate implant loading with definitive restorations in the posterior region appears a valuable and straightforward option to shorten the overall treatment time.

11.
Sci Rep ; 14(1): 7787, 2024 04 02.
Article in English | MEDLINE | ID: mdl-38565933

ABSTRACT

This retrospective study aimed to determine risk factors associated with post-operative bleeding after dentoalveolar surgery in patients taking anticoagulants. Patients taking anticoagulants who were planned to undergo periodontal flap operation, tooth extraction or implant surgery were included. Patients were divided into two subgroups according to the maintenance of anticoagulants following medical consultation: (1) maintenance group and (2) discontinuation group. The analysed patient-related factors included systemic diseases, maintenance of anticoagulants and types of anticoagulant. Intra- and post-operative treatment-related factors, haemostatic methods and post-operative bleeding were collected for statistical analyses. There were 35 post-operative bleeding complications (6.5%) in the 537 included patients: 21 (8.6%) in maintenance group and 14 (4.8%) in discontinuation group. The type of anticoagulant (p = 0.037), tooth extraction combined with bone grafting (p = 0.016) and type of implant surgery (p = 0.032) were significantly related to the post-operative bleeding rate. In the maintenance group, atrial fibrillation [odds ratio (OR) = 6.051] and vitamin K inhibitors (OR = 3.679) were associated with a significantly higher bleeding risk. From this result, it can be inferred that the decision to continue anticoagulants should be made carefully based on the types of anticoagulant and the characteristics of dentoalveolar surgeries performed: extraction with bone grafting, multiple implantations and involvement of maxillary arch.


Subject(s)
Anticoagulants , Atrial Fibrillation , Humans , Anticoagulants/adverse effects , Cohort Studies , Retrospective Studies , Postoperative Hemorrhage/etiology , Postoperative Hemorrhage/chemically induced , Tooth Extraction/adverse effects , Atrial Fibrillation/complications , Administration, Oral
12.
Bioengineering (Basel) ; 11(3)2024 Feb 24.
Article in English | MEDLINE | ID: mdl-38534489

ABSTRACT

This animal study was aimed to evaluate the efficacy of new bone formation and volume maintenance according to the particle type and the collagen membrane function for grafted octacalcium phosphate (OCP) in rabbit calvarial defects. The synthetic bone substitutes were prepared in powder form with 90% OCP and granular form with 76% OCP, respectively. The calvarial defects were divided into four groups according to the particle type and the membrane application. All specimens were acquired 2 weeks (n = 5) and 8 weeks (n = 5) after surgery. According to the micro-CT results, the new bone volume increased at 2 weeks in the 76% OCP groups compared to the 90% OCP groups, and the bone volume ratio was significantly lower in the 90% OCP group after 2 weeks. The histomorphometric analysis results indicated that the new bone area and its ratio in all experimental groups were increased at 8 weeks except for the group with 90% OCP without a membrane. Furthermore, the residual bone graft area and its ratio in the 90% OCP groups were decreased at 8 weeks. In conclusion, all types of OCP could be applied as biocompatible bone graft materials regardless of its density and membrane application. Neither the OCP concentration nor the membrane application had a significant effect on new bone formation in the defect area, but the higher the OCP concentration, the less graft volume maintenance was needed.

14.
iScience ; 27(2): 109022, 2024 Feb 16.
Article in English | MEDLINE | ID: mdl-38357664

ABSTRACT

Cardiovascular disease (CVD) remains a pressing global health concern. While traditional risk prediction methods such as the Framingham and American College of Cardiology/American Heart Association (ACC/AHA) risk scores have been widely used in the practice, artificial intelligence (AI), especially GPT-4, offers new opportunities. Utilizing large scale of multi-center data from 47,468 UK Biobank participants and 5,718 KoGES participants, this study quantitatively evaluated the predictive capabilities of GPT-4 in comparison with traditional models. Our results suggest that the GPT-based score showed commendably comparable performance in CVD prediction when compared to traditional models (AUROC on UKB: 0.725 for GPT-4, 0.733 for ACC/AHA, 0.728 for Framingham; KoGES: 0.664 for GPT-4, 0.674 for ACC/AHA, 0.675 for Framingham). Even with omission of certain variables, GPT-4's performance was robust, demonstrating its adaptability to data-scarce situations. In conclusion, this study emphasizes the promising role of GPT-4 in predicting CVD risks across varied ethnic datasets, pointing toward its expansive future applications in the medical practice.

15.
Gut ; 73(3): 407-441, 2024 02 23.
Article in English | MEDLINE | ID: mdl-38383142

ABSTRACT

At the end of the last century, a far-sighted 'working party' held in Sydney, Australia addressed the clinicopathological issues related to gastric inflammatory diseases. A few years later, an international conference held in Houston, Texas, USA critically updated the seminal Sydney classification. In line with these initiatives, Kyoto Global Consensus Report, flanked by the Maastricht-Florence conferences, added new clinical evidence to the gastritis clinicopathological puzzle.The most relevant topics related to the gastric inflammatory diseases have been addressed by the Real-world Gastritis Initiative (RE.GA.IN.), from disease definitions to the clinical diagnosis and prognosis. This paper reports the conclusions of the RE.GA.IN. consensus process, which culminated in Venice in November 2022 after more than 8 months of intense global scientific deliberations. A forum of gastritis scholars from five continents participated in the multidisciplinary RE.GA.IN. consensus. After lively debates on the most controversial aspects of the gastritis spectrum, the RE.GA.IN. Faculty amalgamated complementary knowledge to distil patient-centred, evidence-based statements to assist health professionals in their real-world clinical practice. The sections of this report focus on: the epidemiology of gastritis; Helicobacter pylori as dominant aetiology of environmental gastritis and as the most important determinant of the gastric oncogenetic field; the evolving knowledge on gastric autoimmunity; the clinicopathological relevance of gastric microbiota; the new diagnostic horizons of endoscopy; and the clinical priority of histologically reporting gastritis in terms of staging. The ultimate goal of RE.GA.IN. was and remains the promotion of further improvement in the clinical management of patients with gastritis.


Subject(s)
Gastritis , Helicobacter Infections , Helicobacter pylori , Stomach Neoplasms , Humans , Helicobacter Infections/complications , Helicobacter Infections/diagnosis , Helicobacter Infections/pathology , Gastritis/diagnosis , Gastritis/epidemiology , Gastritis/pathology , Endoscopy , Stomach Neoplasms/pathology , Gastric Mucosa/pathology
16.
J Clin Periodontol ; 51(6): 766-773, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38356227

ABSTRACT

AIM: To test whether early implant placement into the extraction socket containing an uncalcified provisional matrix leads to successful osseointegration and stable marginal bone levels. MATERIALS AND METHODS: In six mongrel dogs, the mandibular molars were extracted. Three weeks later, early implant placement was performed according to three experimental protocols: (i) flapless implant placement with preservation of the provisional matrix; (ii) flap elevation, socket debridement and implant placement; and (iii) flap elevation, socket debridement, implant placement and guided bone regeneration (GBR). One untreated extraction socket served as a control group. Data analyses were based on histologic slides 3 months after implant placement. RESULTS: There were no differences in bone-to-implant contact between the three experimental groups (66.97%, 58.89% and 60.89%, respectively) (inter-group comparison p = .42). Marginal bone levels, first bone-to-implant contact as well as the thickness of the connective tissue did not reveal any significant differences between the groups (p = .85, .60 and .65, respectively). CONCLUSIONS: Flapless early implant placement into posterior extraction sockets was as effective as an open flap approach in conjunction with GBR. Mineralization of the socket seems to occur irrespective of the presence of dental implants or biomaterials.


Subject(s)
Osseointegration , Tooth Socket , Animals , Dogs , Osseointegration/physiology , Tooth Socket/surgery , Tooth Extraction , Surgical Flaps/surgery , Guided Tissue Regeneration, Periodontal/methods , Dental Implantation, Endosseous/methods , Dental Implants , Mandible/surgery , Debridement , Connective Tissue , Molar , Immediate Dental Implant Loading/methods
18.
Nano Lett ; 24(8): 2574-2580, 2024 Feb 28.
Article in English | MEDLINE | ID: mdl-38349338

ABSTRACT

The highly programmable and responsive molecular recognition properties of DNA provide unparalleled opportunities for fabricating dynamic nanostructures capable of structural transformation in response to various external stimuli. However, they typically operate in tightly controlled environments because certain conditions (ionic strength, pH, temperature, etc.) must be met for DNA duplex formation. In this study, we adopted site-specific enzymatic ligation and DNA-based layer-by-layer thin film fabrication to build shape-morphing DNA-linked nanoparticle films operational in a broad range of environments. The ligated films remained intact in unusual conditions such as pure water and high temperature causing dissociation of DNA duplexes and showed predictable and reversible shape morphing in response to various environmental changes and DNA exchange reactions. Furthermore, domain-selective ligation combined with photoinduced interlayer mixing allowed for the fabrication of unusual edge-sealed double-layered films through midlayer etching, which is difficult to realize by other methods.


Subject(s)
Nanoparticles , Nanostructures , DNA/chemistry , Water , Temperature
19.
Nanomaterials (Basel) ; 14(4)2024 Feb 12.
Article in English | MEDLINE | ID: mdl-38392722

ABSTRACT

This study developed an advanced 850 nm centered distributed Bragg reflector (DBR) (broadband DBR) composed of nanomaterial-based multiple structures to improve the optical efficiency of an 850 nm near-infrared light-emitting diode (NIR-LED). A combined 850 nm centered broadband DBR was fabricated by growing an 800 nm centered ten-pair DBR on a 900 nm centered ten-pair DBR (denoted as a combined DBR). The combined DBR exhibited a slightly wider peak band than conventional DBRs. Furthermore, the peak band width of the combined DBR significantly increased upon using a reflective AlAs buffer layer that reduced the overlapped reflection. The output power (20.5 mW) of NIR-LED chips using the combined DBR with an AlAs buffer layer exceeded that of a conventional 850 nm centered DBR (14.5 mW) by more than 40%. Results indicated that combining the optical conditions of wavelengths and the AlAs buffer layer effectively strengthened the broadband effect of the DBR and increased the optical efficiency of the 850 nm NIR-LED.

20.
Sci Rep ; 14(1): 317, 2024 01 03.
Article in English | MEDLINE | ID: mdl-38172381

ABSTRACT

The study of the large paraphyletic group of extinct 'palaeoniscoid' fishes has shed light on the diversity and evolutionary history of basal actinopterygians. However, only a little ontogenetic information about 'palaeoniscoids' is known because their records in the early stages of development are scarce. Here, we report on a growth series of 'palaeoniscoids' in the juvenile stage from the Upper Triassic Amisan Formation of South Korea. Fourteen specimens, including five counterpart specimens, represent a new taxon, Megalomatia minima gen. et sp. nov., exhibiting ontogeny and exceptional preservation with the eyes possibly containing the crystalline lens, the otoliths, and the lateral line canals without covering scales. This discovery allows us to discuss the adaptations and evolution of basal actinopterygians in more detail than before. The otoliths in situ of Megalomatia support the previous interpretation that basal actinopterygians have a sagitta as the largest otolith. The trunk lateral line canal, which runs under the scales instead of passing through them, represents a plesiomorphic gnathostome trait. Notably, the large protruded eyes suggest that Megalomatia probably has binocular vision, which would have played a significant role in targeting and catching prey with the primitive jaw structure. In addition, the firstly formed skeletal elements such as the jaws, pectoral girdle, and opercular series, and the posteroanterior pattern of squamation development are likely linked to the adaptation of young individuals to increase their viability for feeding, respiration, and swimming.


Subject(s)
Fossils , Jaw , Animals , Fishes , Republic of Korea , Phylogeny
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