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1.
ACS Appl Mater Interfaces ; 16(28): 36527-36538, 2024 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-38961586

RESUMO

The development of broadband photosensors has become crucial in various fields. Indium-gallium-zinc oxide (IGZO, In:Ga:Zn = 1:1:1) phototransistors with PbS quantum dots (QDs) have shown promising features for such sensors, such as reasonable mobility, low leakage current, good photosensitivity, and low-cost fabrication. However, the instability of PbS QD/IGZO phototransistors under an air atmosphere and prolonged storage remain serious concerns. In this article, two concepts to improve the reliability of PbS QD/IGZO phototransistors were implemented. P-type doping in the PbS QD layer through oxidation allows increasing the built-in potential between IGZO and PbS QDs, leading to enhancement in photoinduced electron-hole pair creation. Second, agglomeration and fusion of a PbS QDs layer were controlled via thermal annealing, which facilitated the transport of photocreated carriers. The p-type doping and interconnection of a PbS QD layer can be achieved by deposition and subsequent thermal annealing of gallium oxide (Ga2O3) on PbS QD/IGZO stacks. The resulting Ga2O3/PbS QD/IGZO phototransistors exhibited high-performance switching characteristics under dark conditions. Notably, they showed a remarkable photoresponsivity of 196.69 ± 4.05 A/W and a detectivity of (5.47 ± 1.4) × 1012 Jones even at a long-wavelength illumination of 1550 nm. While the unpassivated PbS/IGZO phototransistor suffered serious degradation in optical performance after 2 weeks of storage, the Ga2O3/PbS QD/IGZO phototransistor demonstrated enhanced stability, maintaining high performance for over 5 weeks. These findings suggest that Ga2O3/PbS QD/IGZO phototransistors offer a feasible approach for the fabrication of large-scale active matrix broadband photosensor arrays, potentially revolutionizing optical sensing in various cutting-edge applications.

2.
Gland Surg ; 13(6): 852-863, 2024 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-39015706

RESUMO

Background: Although dual-plane subpectoral breast reconstruction has been widely implemented in implant-based breast reconstruction, animation deformities remain an issue. Recent advances in skin flap circulation detection have increased the use of prepectoral reconstruction. A partial muscle-splitting subpectoral plane was introduced to decrease the visibility of the implant edge. However, there is yet to be a direct comparison of these methods for optimal results, including changes in implant position after reconstruction. This study aims to compare the incidence of complications such as rippling, animation deformity, implant upward migration between the dual-plane, the partial muscle splitting subpectoral and the prepectoral reconstruction group. In addition, multivariate analysis was conducted to identify the risk factors of complications. Methods: We retrospectively investigated 349 patients who underwent unilateral direct-to-implant breast reconstruction from January 2017 to October 2020. Implants were inserted into the dual-plane subpectoral (P2) or partial muscle-splitting subpectoral (P1, the muscle slightly covering the upper edge of the implant) or the prepectoral pocket (P0). Postoperative outcomes and at least 2 years of follow-up complications were compared. Results: There was no significant difference in rippling (P=0.62) or visible implant edges on the upper pole (P=0.62) among the three groups. In contrast, the P0 group had a lower incidence of seroma (P=0.008), animation deformity (P<0.001), breast pain (P=0.002), and upward implant migration (P0: 1.09%, P1: 4.68%, P2: 38.37%, P<0.001). According to the multivariate analysis, P2 resulted in a greater risk of seroma (odds ratio: 4.223, P=0.002) and implant upward migration (odds ratio: 74.292, P<0.001) than did P0. Conclusions: P0 and P1 showed better postoperative outcomes than P2. Additionally, P0 had less implant migration than P1. Even though P1 minimally dissects the muscle, the location of the implant may change. Considering that muscle contraction can deteriorate symmetry and aesthetic results, the P0 method may be the most favorable.

3.
Sci Rep ; 14(1): 16322, 2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-39009704

RESUMO

Age-related macular degeneration (AMD) is one of the leading causes of blindness. AMD is currently incurable; the best solution is to prevent its occurrence. To develop drugs for AMD, it is crucial to have a model system that mimics the symptoms and mechanisms in patients. It is most important to develop safer and more effective anti-AMD drug. In this study, the dose of A2E and the intensity of blue light were evaluated to establish an appropriate atrophic in vitro model of AMD and anti-AMD effect and therapeutic mechanism of Codonopsis lanceolata. The experimental groups included a control group an AMD group treated with A2E and blue light, a lutein group treated with 25 µM lutein after AMD induction, and three groups treated with different doses of C. lanceolata (10, 20, and 50 µg/mL) after AMD induction. Intrinsic apoptotic pathway (Bcl-2 family), anti-oxidative system (Keap1/Nrf2/HO-1 antioxidant response element), and anti-carbonyl effect (4-hydroxynonenal [4-HNE]) were evaluated using immunofluorescence, MTT, TUNEL, FACS, and western blotting analyses. A2E accumulation in the cytoplasm of ARPE-19 cells depending on the dose of A2E. Cell viability of ARPE-19 cells according to the dose of A2E and/or blue light intensity. The population of apoptotic or necrotic cells increased based on the A2E dose and blue light intensity. Codonopsis lanceolata dose-dependently prevented cell death which was induced by A2E and blue light. The antiapoptotic effect of that was caused by activating Keap1/Nrf2/HO-1 pathway, suppressing 4-HNE, and modulating Bcl-2 family proteins like increase of antiapoptotic proteins such as Bcl-2 and Bcl-XL and decrease of proapoptotic protein such as Bim. Based on these findings, 30 µM A2E and 20 mW/cm2 blue light on adult retinal pigment epithelium-19 cells was an appropriate condition for AMD model and C. lanceolata shows promise as an anti-AMD agent.


Assuntos
Apoptose , Codonopsis , Degeneração Macular , Fator 2 Relacionado a NF-E2 , Estresse Oxidativo , Codonopsis/química , Humanos , Degeneração Macular/tratamento farmacológico , Degeneração Macular/metabolismo , Degeneração Macular/patologia , Estresse Oxidativo/efeitos dos fármacos , Apoptose/efeitos dos fármacos , Fator 2 Relacionado a NF-E2/metabolismo , Extratos Vegetais/farmacologia , Antioxidantes/farmacologia , Proteína 1 Associada a ECH Semelhante a Kelch/metabolismo , Linhagem Celular , Aldeídos/farmacologia , Epitélio Pigmentado da Retina/efeitos dos fármacos , Epitélio Pigmentado da Retina/metabolismo , Epitélio Pigmentado da Retina/patologia , Luz/efeitos adversos , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo
4.
BMC Musculoskelet Disord ; 25(1): 534, 2024 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-38997683

RESUMO

BACKGROUND: The rotational change after using a flexible intramedullary (IM) nail for femoral shaft fractures has been a concern for many surgeons. Recently, a statistical shape model (SSM) was developed for the three-dimensional reconstruction of the femur from two-dimensional plain radiographs. In this study, we measured postoperative femoral anteversion (FAV) in patients diagnosed with femoral shaft fractures who were treated with flexible IM nails and investigated age-related changes in FAV using the SSM. METHODS: This study used radiographic data collected from six regional tertiary centers specializing in pediatric trauma in South Korea. Patients diagnosed with femoral shaft fractures between September 2002 and June 2020 and patients aged < 18 years with at least two anteroposterior (AP) and lateral (LAT) femur plain radiographs obtained at least three months apart were included. A linear mixed model (LMM) was used for statistical analysis. RESULTS: Overall, 72 patients were included in the study. The average patient age was 7.6 years and the average follow-up duration was 6.8 years. The average FAV of immediate postoperative images was 27.5 ± 11.5°. Out of 72 patients, 52 patients (72.2%) showed immediate postoperative FAV greater than 20°. The average FAV in patients with initial FAV > 20° was 32.74°, and the LMM showed that FAV decreased by 2.5° (p = 0.0001) with each 1-year increase from the time of initial trauma. CONCLUSIONS: This study explored changes in FAV after femoral shaft fracture using a newly developed technology that allows 3D reconstruction from uncalibrated 2D images. There was a pattern of change on the rotation of the femur after initial fixation, with a 2.5° decrease of FAV per year.


Assuntos
Pinos Ortopédicos , Fraturas do Fêmur , Fêmur , Fixação Intramedular de Fraturas , Humanos , Fraturas do Fêmur/cirurgia , Fraturas do Fêmur/diagnóstico por imagem , Fixação Intramedular de Fraturas/instrumentação , Fixação Intramedular de Fraturas/métodos , Fixação Intramedular de Fraturas/efeitos adversos , Criança , Feminino , Masculino , Pré-Escolar , Adolescente , Fêmur/cirurgia , Fêmur/diagnóstico por imagem , Estudos Retrospectivos , República da Coreia/epidemiologia , Resultado do Tratamento , Seguimentos , Anteversão Óssea/diagnóstico por imagem , Anteversão Óssea/etiologia , Imageamento Tridimensional
5.
J Gastric Cancer ; 24(3): 257-266, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38960885

RESUMO

PURPOSE: We conducted a randomized prospective trial (KLASS-07 trial) to compare laparoscopy-assisted distal gastrectomy (LADG) and totally laparoscopic distal gastrectomy (TLDG) for gastric cancer. In this interim report, we describe short-term results in terms of morbidity and mortality. METHODS AND METHODS: The sample size was 442 participants. At the time of the interim analysis, 314 patients were enrolled and randomized. After excluding patients who did not undergo planned surgeries, we performed a modified per-protocol analysis of 151 and 145 patients in the LADG and TLDG groups, respectively. RESULTS: The baseline characteristics, including comorbidity status, did not differ between the LADG and TLDG groups. Blood loss was somewhat higher in the LADG group, but statistical significance was not attained (76.76±72.63 vs. 62.91±65.68 mL; P=0.087). Neither the required transfusion level nor the operation or reconstruction time differed between the 2 groups. The mini-laparotomy incision in the LADG group was significantly longer than the extended umbilical incision required for specimen removal in the TLDG group (4.79±0.82 vs. 3.89±0.83 cm; P<0.001). There were no between-group differences in the time to solid food intake, hospital stay, pain score, or complications within 30 days postoperatively. No mortality was observed in either group. CONCLUSIONS: Short-term morbidity and mortality rates did not differ between the LADG and TLDG groups. The KLASS-07 trial is currently underway. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT03393182.


Assuntos
Gastrectomia , Laparoscopia , Neoplasias Gástricas , Humanos , Neoplasias Gástricas/cirurgia , Neoplasias Gástricas/mortalidade , Gastrectomia/métodos , Gastrectomia/efeitos adversos , Gastrectomia/mortalidade , Laparoscopia/métodos , Laparoscopia/efeitos adversos , Laparoscopia/mortalidade , Feminino , Masculino , Pessoa de Meia-Idade , Idoso , Estudos Prospectivos , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/mortalidade , Complicações Pós-Operatórias/etiologia , Morbidade , Adulto
7.
Artigo em Inglês | MEDLINE | ID: mdl-38962280

RESUMO

Age related macular degeneration and other retinal degenerative disorders are characterized by disruption of the outer blood retinal barrier (oBRB) with subsequent ischemia, neovascularization, and atrophy. Despite the treatment advances, there remains no curative therapy, and no treatment targeted at regenerating native-like tissue for patients with late stages of the disease. Here we present advances in tissue engineering, focusing on bioprinting methods of generating tissue allowing for safe and reliable production of oBRB as well as tissue reprogramming with induced pluripotent stem cells for transplantation. We compare these approaches to organ-on-a-chip models for studying the dynamic nature of physiologic conditions. Highlighted within this review are studies that employ good manufacturing practices and use clinical grade methods that minimize potential risk to patients. Lastly, we illustrate recent clinical applications demonstrating both safety and efficacy for direct patient use. These advances provide an avenue for drug discovery and ultimately transplantation.

8.
Sci Rep ; 14(1): 15472, 2024 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-38969796

RESUMO

This study evaluated the determinants of mortality and the T cell immune response in patients with persistent Staphylococcus aureus bacteremia (SAB). This was a prospective cohort study and patients with confirmed SAB were enrolled from 2008 to 2020. We compared clinical, microbiological, and genotypic features between surviving and deceased patients with persistent SAB. The concentrations of cytokines and the proportions of IFN-γ secreting CD4+ T cells were measured serially during the bacteremia period. Of the 1760 patients, 242 had persistent bacteremia (PB), and 49 PB patients died within 30 days. In the multivariate analysis, the APACHE II score and female sex were independently associated with 30 days mortality. The level of IL-10 was significantly increased in the plasma of patients with a high Pitt bacteremia score and those who died within 12 weeks from the index day. The proportion of IFN-γ-secreting CD4+ T cells were the highest just before the positive-to-negative conversion of blood cultures in patients with a low Pitt bacteremia score and those who survived for 12 weeks. The level of IL-10 is correlated with clinical outcomes in PB patients. IFN-γ secreting CD4+ T cells might play a pivotal role in SAB PB.


Assuntos
Bacteriemia , Linfócitos T CD4-Positivos , Infecções Estafilocócicas , Staphylococcus aureus , Humanos , Masculino , Feminino , Bacteriemia/mortalidade , Bacteriemia/microbiologia , Bacteriemia/imunologia , Linfócitos T CD4-Positivos/imunologia , Infecções Estafilocócicas/mortalidade , Infecções Estafilocócicas/imunologia , Infecções Estafilocócicas/microbiologia , Staphylococcus aureus/imunologia , Pessoa de Meia-Idade , Fatores de Risco , Idoso , Estudos Prospectivos , Interferon gama/sangue , Interferon gama/metabolismo , Interleucina-10/sangue , Adulto , Citocinas/sangue , Citocinas/metabolismo
9.
Microbiol Spectr ; : e0033324, 2024 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-38916352

RESUMO

The incidence of heterogeneous vancomycin-intermediate Staphylococcus aureus (hVISA) infection is increasing and is associated with vancomycin treatment failures. However, studies investigating the risk factors for treatment failure in hVISA infection are limited. Patients with hVISA bacteremia treated with vancomycin over 7 days between August 2008 and June 2020 were enrolled in this study. Clinical and microbiological characteristics were compared between vancomycin treatment failure and success groups to identify the risk factors for vancomycin treatment failure. Among the 180 patients with hVISA bacteremia, 102 patients treated with vancomycin over 7 days were included. Vancomycin treatment failed in 80 (78%) patients. Patients in the vancomycin treatment failure group were older (P < 0.001) and more frequently had solid cancer (P = 0.04) than those in the vancomycin treatment success group. Solid organ transplantation (SOT) was more frequent (P < 0.001) in the vancomycin treatment success group. The Charlson comorbidity index (P = 0.01) and Acute Physiology and Chronic Health Evaluation II scores (P < 0.001) were higher in the vancomycin treatment failure group. In multivariate analysis, independent risk factors for vancomycin treatment failure were old age and severity of bacteremia. SOT and vancomycin minimal inhibitory concentration (MIC) ≤ 1.0 mg/L using the broth microdilution (BMD) method were associated with successful vancomycin treatment. Old age and infection severity were independent risk factors for vancomycin treatment failure. Vancomycin MIC using the BMD method is an important risk factor for vancomycin treatment failure, and its use should be considered in hVISA bacteremia.IMPORTANCEIn this study, we assessed the clinical and microbiological characteristics of heterogeneous vancomycin-intermediated Staphylococcus aureus (hVISA) bacteremia and identified risk factors for vancomycin treatment failure. We found that advanced age and severity of infection were independent risk factors for vancomycin treatment failure. On the other hand, solid organ transplantation and a low vancomycin minimal inhibitory concentration were associated with successful vancomycin treatment. This study highlights the importance of vancomycin minimal inhibitory concentration in hVISA bacteremia.

10.
Adv Colloid Interface Sci ; 331: 103245, 2024 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-38945073

RESUMO

Quantum dots (QDs), a novel category of semiconductor materials, exhibit extraordinary capabilities in tuning optical characteristics. Their emergence in biophotonics has been noteworthy, particularly in bio-imaging, biosensing, and theranostics applications. Although conventional QDs such as PbS, CdSe, CdS, and HgTe have garnered attention for their promising features, the presence of heavy metals in these QDs poses significant challenges for biological use. To address these concerns, the development of Ag chalcogenide QDs has gained prominence owing to their near-infrared emission and exceptionally low toxicity, rendering them suitable for biological applications. This review explores recent advancements in Ag chalcogenide QDs, focusing on their synthesis methodologies, surface chemistry modifications, and wide-ranging applications in biomedicine. Additionally, it identifies future directions in material science, highlighting the potential of these innovative QDs in revolutionizing the field.

11.
Eval Program Plann ; 106: 102463, 2024 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-38925047

RESUMO

This study comprehensively explores the factors that lead to low performers in an organization. A thorough literature review was conducted to construct an interview guide and obtain classification criteria for the factors that lead to low performers. Managers and low performers at multiple firms were interviewed individually to understand the various phenomena related to low performers in organizations. Based on the content of these interviews, 12 factors, classified into individual, leader, work, and organizational dimensions, were identified after three rounds of revisions by business administration experts. Next, a case study of Korea's S Life Insurance Company was conducted to examine the practical implications of the factors that contribute to creating low performers. In this case study, the analytic hierarchy process (AHP), involving eight departmental heads S Life Insurance Company's HR division, was utilized to identify the main factors that must be considered when evaluating low performers. While previous studies have examined low performers either at the individual, organizational, or institutional levels, this study presents a comprehensive and integrated evaluation framework of the factors that cause low performers. The proposed framework facilitates the identification and evaluation of low performers in various organizations and industries, and thus has practical implications in terms of establishing strategies to manage low performers more efficiently and improve organizational performance.

12.
Cancers (Basel) ; 16(12)2024 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-38927908

RESUMO

BACKGROUND/OBJECTIVE: This study aimed to compare complication rates between pylorus-preserving gastrectomy (PPG) and distal gastrectomy (DG) using Korean nationwide survey data and propensity score weighting (PSW). PPG preserves gastric function but may lead to more postoperative complications than DG. METHODS AND RESULTS: We analyzed 9424 gastric cancer patients who underwent either DG (n = 9183) or PPG (n = 241). PSW balanced variables such as age, sex, TNM stage, comorbidities, ASA score, and surgical approach. Before PSW, 87.8% of DG patients and 87.1% of PPG patients had no complications (p = 0.053). Severe complications (Clavien-Dindo IIIa or higher) were more frequent in PPG (6.6%) than in DG (3.8%) (p = 0.039). After PSW, overall complication rates (p = 0.960) and severe complication rates (p = 0.574) were similar between groups. Incidence rates of anastomotic stricture and leakage were higher in PPG (2.9% and 1.7%) compared to DG (0.6% and 0.5%) (p = 0.001 and 0.036) before PSW, but these differences were not significant after PSW (p = 0.999 and 0.123). CONCLUSION: The PSW-adjusted analysis indicates no significant difference in overall and severe complication rates between PPG and DG in gastric cancer patients.

13.
J Chem Phys ; 160(23)2024 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-38888374

RESUMO

To tackle the challenge of ground-level ozone pollution, this study proposed a potential catalytic design approach for ozone decomposition using Cu-Mn bimetallic oxide. This approach is grounded in an understanding of the intrinsic reactivity for catalyst and incorporates a novel potassium-driven low-temperature oxidation process for catalyst synthesis. The research highlights the creation of a highly reactive Cu-Mn oxide phase with extensive defect coverage, leading to significantly increased reaction rates. It also identifies the MnO2(100) facet as a crucial active phase, where oxygen vacancies simultaneously enhance O3 adsorption and decomposition, albeit with a concurrent risk of O2 poisoning due to the stabilization of adsorbed O2. Crucially, the incorporation of Cu offsets the effects of oxygen vacancies, influencing conversion rates and lessening O2 poisoning. The synergistic interplay between Cu and oxygen vacancies elevates the performance of the defect-rich Cu-Mn oxide catalyst. By combining computational and experimental methods, this study not only advances the understanding of the Cu-Mn oxide system for ozone decomposition but also contributes valuable insights into developing more efficient catalysts to mitigate ozone pollution.

14.
Heliyon ; 10(11): e31643, 2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38882331

RESUMO

This study analyzed spatiotemporal variation and long-term trends in water quality indicators and trophic state conditions in an Asian temperate reservoir, Juam Reservoir (JR), and developed models that forecast algal chlorophyll (CHL-a) over a period of 30 years, 1993-2022. The analysis revealed that there were longitudinal gradients in water quality indicators along the reservoir, with notable influences from tributaries and seasonal variations in nutrient regimes and suspended solids. The empirical model showed phosphorus was found to be the key determinant of algal biomass, while suspended solids played a significant role in regulating water transparency. The trophic state indices indicated varying levels of trophic status, ranging from mesotrophic to eutrophic. Eutrophic states were particularly observed in zones after the summer monsoons, indicating a heightened risk of algal blooms, which were more prevalent in flood years. The analysis of trophic state index deviation suggested that phosphorus availability strongly influences the reservoir trophic status, with several episodes of non-algal turbidity at each site during Mon. Increases in non-algal turbidity were more prevalent during the monsoon in flood years. This study also highlighted overall long-term trends in certain water quality parameters, albeit with indications of shifting pollution sources towards non-biodegradable organic matter. According to the machine learning tests, a random forest (RF) model strongly predicted CHL-a (R2 = 0.72, p < 0.01), except for algal biomass peaks (>60 µg/L), compared to all other models. Overall, our research suggests that CHL-a and trophic variation are primarily regulated by the monsoon intensity and predicted well by the machine learning RF model.

15.
Nat Commun ; 15(1): 5162, 2024 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-38890313

RESUMO

Two-dimensional (2D) ferroelectric materials have emerged as significant platforms for multi-functional three-dimensional (3D) integrated electronic devices. Among 2D ferroelectric materials, ferro-ionic CuInP2S6 has the potential to achieve the versatile advances in neuromorphic computing systems due to its phase tunability and ferro-ionic characteristics. As CuInP2S6 exhibits a ferroelectric phase with insulating properties at room temperature, the external temperature and electrical field should be required to activate the ferro-ionic conduction. Nevertheless, such external conditions inevitably facilitate stochastic ionic conduction, which completely limits the practical applications of 2D ferro-ionic materials. Herein, free-standing 2D ferroelectric heterostructure is mechanically manipulated for nano-confined conductive filaments growth in free-standing 2D ferro-ionic memristor. The ultra-high mechanical bending is selectively facilitated at the free-standing area to spatially activate the ferro-ionic conduction, which allows the deterministic local positioning of Cu+ ion transport. According to the local flexoelectric engineering, 5.76×102-fold increased maximum current is observed within vertical shear strain 720 nN, which is theoretically supported by the 3D flexoelectric simulation. In conclusion, we envision that our universal free-standing platform can provide the extendable geometric solution for ultra-efficient self-powered system and reliable neuromorphic device.

17.
ACS Nano ; 18(24): 16051-16058, 2024 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-38840340

RESUMO

Indium phosphide (InP) quantum dots (QDs) have attracted significant interest as next-generation light-emitting materials. However, the synthesis of blue-emitting InP-based QDs has lagged behind that of established green- and red-emitting InP QDs. Herein, we present a strategy to synthesize blue-emitting QDs by forming an InGaP alloy composition. The introduction of asymmetric In-carboxylate and Ga-carboxylate complexes resulted in a balanced synthetic reactivity between In-P and Ga-P, leading to the formation of InGaP alloyed QDs. The resultant In1-xGaxP alloyed QDs exhibited a broad range of photoluminescence (PL) tunability, spanning from 535 nm (InP) to 465 nm (In0.62Ga0.38P), depending on the In/Ga ratio used in the synthesis. In contrast, synthesis with symmetric In-carboxylate and Ga-carboxylate complexes produced a core/shell structure of InP/GaP QDs, which did not exhibit a blue shift of the PL peak with Ga addition. By employing a core/shell structure of In0.62Ga0.38P/ZnS QDs, we achieved a PL quantum yield of 42% at 475 nm. This work highlights the material-processing strategy essential for forming alloyed structures in III-V ternary systems.

18.
ACS Appl Mater Interfaces ; 16(27): 35505-35515, 2024 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-38935928

RESUMO

The commercialization of 3D heterogeneous integration through hybrid bonding has accelerated, and accordingly, Cu-polymer bonding has gained significant attention as a means of overcoming the limitations of conventional Cu-SiO2 hybrid bonding, offering high compatibility with other fabrication processes. Polymers offer robust bonding strength and a low dielectric constant, enabling high-speed signal transmission with high reliability, but suffer from low thermomechanical stability. Thermomechanical stability of polymers was not achieved previously because of thermal degradation and unstable anchoring. To overcome these limitations, wafer-scale Cu-polymer bonding via N-heterocyclic carbene (NHC) nanolayers was presented for 3D heterogeneous integration, affording ultrastable packing density, crystallinity, and thermal properties. NHC nanolayers were deposited on copper electrodes via electrochemical deposition, and wafer-scale 3D heterogeneous integration was achieved by adhesive bonding at 170 °C for 1 min. Ultrastable conductivity and thermomechanical properties were observed by the spatial mapping of conductivity, work function, and force-distance curves. With regard to the characterization of NHC nanolayers, low-temperature bonding, robust corrosion inhibition, enhanced electrical conductivity, back-end-of-line process compatibility, and fabrication process reduction, NHC Cu/polymer bonding provides versatile advances in 3D heterogeneous integration, indicating that NHC Cu/polymer bonding can be utilized as a platform for future 3D vertical chip architectures.

19.
Am J Perinatol ; 2024 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-38889887

RESUMO

OBJECTIVE: This study aimed to determine the effect of the Omicron variant on pregnancy-related and neonatal outcomes among the Black-dominant population. STUDY DESIGN: We performed a single-center, retrospective cohort study during the prepandemic period from December 1, 2019, to February 29, 2020, and the Omicron surging period from December 1, 2021, to February 28, 2022. A total of 518 pregnant women were admitted for delivery during the study period. Multiple gestations (n = 21) and deliveries at less than 20 weeks of gestation (n = 5) were excluded. We analyzed and compared the sociodemographic and clinical data from mothers and their neonates between the two cohorts as well as between severe acute respiratory syndrome-coronavirus-2 (SARS-CoV-2) positive and negative mothers during the Omicron surge. Subgroup analyses were also conducted specifically among the Black-only population. RESULTS: The cohorts were predominantly Black (88.6%), with smaller proportions of Hispanic (8.9%), Asian (0.8%), White (0.8%), and other ethnicities (0.8%). Of 492 singleton deliveries, 275 live births, 8 (2.8%) stillbirths, and 31 (11.3%) preterm births (PTBs) occurred during the prepandemic period, and 207 live births, 2 (1%) stillbirths, and 33 (15.9%) PTBs occurred during the Omicron wave. There was no statistically significant difference in the rates of PTBs, stillbirths, medically indicated PTBs, and cesarean delivery between the two cohorts. SARS-CoV-2-positive mothers were not at an increased risk of adverse outcomes. However, neonatal intensive care unit (NICU) admission rate significantly increased among neonates born to SARS-CoV-2 positive mothers compared with negative mothers (32.3 vs. 16.5%, p = 0.038). In subgroup analyses among Black individuals, this difference was not observed. CONCLUSION: There was no significant difference in pregnancy-related or neonatal outcomes in the Black-dominant population between the two cohorts. SARS-CoV-2 infection did not alter these findings except for an increased NICU admission rate among neonates born to SARS-CoV-2-positive mothers. KEY POINTS: · Most pregnant women infected with SARS-CoV-2 during the Omicron wave were asymptomatic.. · The Omicron wave did not increase the risk of pregnancy-related or neonatal adverse outcomes when compared with the prepandemic period.. · Maternal SARS-CoV-2 infection increased NICU admission rate.. · Among Black individuals, no significant increase in adverse outcomes was observed during the Omicron pandemic..

20.
Polymers (Basel) ; 16(10)2024 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-38794540

RESUMO

This study develops a vitamin C controlled-release system, trackable via color changes as a function of vitamin C release. The system is composed of coaxial microfibers prepared via coaxial electrospinning, with a core of poly(ethylene oxide) (PEO) incorporating vitamin C, and a shell composed of polycaprolactone (PCL) containing polydiacetylene (PDA) as the color-changing material. The shell thickness is controlled by adjusting the amount of PCL ejected during electrospinning, allowing regulation of the release rate of vitamin C. When vitamin C added to PEO penetrates the PCL layer, the color of PDA changes from blue to red, indicating a color change. The results of this study can be applied to devices that require immediate detection of vitamin C release levels.

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