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1.
Korean J Ophthalmol ; 2024 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-38665113

RESUMO

Purpose: In the present study, we introduce human lacrimal gland imaging using an ultrasound biomicroscopy (UBM) with a soft cover and show their findings. Methods: The representative UBM findings of palpebral lobes in seven subjects (4 with non-Sjögren dry eye syndrome, 1 with Sjögren syndrome, and 2 healthy subjects) were described in this study. To prolapse the palpebral lobe, the examiner pulled the temporal part of the upper eyelid in the superotemporal direction and directed the subject to look in the inferonasal direction. We scanned the palpebral lobes longitudinally and transversely using UBM. We used an Aviso UBM (Quantel Medical, Clermont-Ferrand, France) with a 50 MHz linear probe and ClearScan. Results: In UBM of two healthy subjects, the echogenicity of the lacrimal gland was lower than that of the sclera and homogeneous. But, the parenchyma of a patient with Sjögren dry eye syndrome was quite inhomogeneous compared to the healthy subjects. In two patients with dry eye syndrome, we were able to observe some lobules in the parenchyma. We could find excretory ducts running parallel at the surface of the longitudinal section in some subjects. In the longitudinal UBM scan of a subject, we observed a tubular structure at a depth of 1500 µm that was considered a blood vessel. It ran from the superonasal to the inferotemporal direction. In a subject, we observed a large cyst beneath the conjunctiva. Conclusions: Lacrimal gland imaging using UBM has both advantages of OCT and sonography, and could be useful for evaluating dry eye syndrome.

2.
Ophthalmol Ther ; 2024 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-38581606

RESUMO

INTRODUCTION: This study is a retrospective case series to compare the accuracy of the Barrett toric calculator using predicted posterior corneal astigmatism (PCA) and PCA measurements using swept-source optical coherence tomography (SS-OCT) and a Scheimpflug camera. This evaluation was conducted across different types of anterior and posterior astigmatism. METHODS: A total of 146 eyes from 146 patients implanted with toric intraocular lenses were included. Mean absolute prediction error, standard deviation of prediction error, and the percentage of eyes with prediction errors within ±0.50 diopters (D) were calculated using vector analysis. Biometric measurements were conducted using the IOLMaster 700 and Pentacam HR. A subgroup analysis was conducted based on the orientation of both anterior and posterior corneal astigmatism. RESULTS: The Barrett toric calculator with predicted PCA yielded the best results, with 78.1% having a prediction error ≤ 0.50 D, which was a significantly higher percentage than the Barrett formula with the two versions of measured PCA (P < 0.05). In the subgroup with a horizontally steep meridian PCA using the IOLMaster 700, the Barrett formula with predicted PCA yielded the best results, with 78.3% of cases having a prediction error of less than 0.5 D. This percentage was significantly higher than the other two measured PCA subgroups (P < 0.05). CONCLUSION: The Barrett toric formula with predicted PCA demonstrated a statistically significantly higher proportion of cases with a prediction error ≤ 0.5 D compared to the two measured PCA formulas (from the IOLMaster 700 or Pentacam). This trend persisted even when the posterior corneal astigmatism was horizontally steep.

4.
Korean J Ophthalmol ; 38(2): 105-112, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38351485

RESUMO

PURPOSE: To evaluate the refractive outcomes after ultrathin Descemet stripping automated endothelial keratoplasty (UT-DSAEK) combined with phacoemulsification and intraocular lens implantation (triple procedure) in the South Korean population. METHODS: This retrospective observational study included 37 eyes of 36 patients who underwent the UT-DSAEK triple procedure between 2012 and 2021 in a single tertiary hospital. Preoperative and postoperative refractive outcomes and endothelial parameters at 1, 3, 6, and 12 months were observed. RESULTS: At the final postoperative 12-month period, the average best-corrected visual acuity was 0.4 ± 0.5 in logarithm of the minimum angle of resolution. The mean endothelial cell density at 12 months was 1,841.92 ± 731.24 cells/mm2, indicating no significant endothelial cell loss compared to the baseline (p = 0.128). The mean postoperative central corneal thickness at 12 months was 597.41 ± 86.26 µm. The postoperative mean absolute error at 12 months was 0.96 ± 0.89 diopters (D) and mean error was 0.89 ± 0.97 D. CONCLUSIONS: The results of our South Korean cohort study on UT-DSAEK triple surgery showed favorable and safe outcomes. Regardless of graft thickness, it should be noted that a hyperopic shift of 1.00 to 2.00 D needs to be considered in the case of UT-DSAEK triple surgery.


Assuntos
Catarata , Transplante de Córnea , Ceratoplastia Endotelial com Remoção da Lâmina Limitante Posterior , Distrofia Endotelial de Fuchs , Humanos , Acuidade Visual , Estudos de Coortes , Refração Ocular , Estudos Retrospectivos , Ceratoplastia Endotelial com Remoção da Lâmina Limitante Posterior/métodos , Endotélio Corneano/transplante , Distrofia Endotelial de Fuchs/cirurgia
5.
Appl Microbiol Biotechnol ; 108(1): 224, 2024 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-38376550

RESUMO

The occurrence of autophagy in recombinant Chinese hamster ovary (rCHO) cell culture has attracted attention due to its effects on therapeutic protein production. Given the significance of glycosylation in therapeutic proteins, this study examined the effects of autophagy-inhibiting chemicals on sialylation of Fc-fusion glycoproteins in rCHO cells. Three chemical autophagy inhibitors known to inhibit different stages were separately treated with two rCHO cell lines that produce the same Fc-fusion glycoprotein derived from DUKX-B11 and DG44. All autophagy inhibitors significantly decreased the sialylation of Fc-fusion glycoprotein in both cell lines. The decrease in sialylation of Fc-fusion glycoprotein is unlikely to be attributed to the release of intracellular enzymes, given the high cell viability and low activity of extracellular sialidases. Interestingly, the five intracellular nucleotide sugars remained abundant in cells treated with autophagy inhibitors. In the mRNA expression profiles of 27 N-glycosylation-related genes using the NanoString nCounter system, no significant differences in gene expression were noted. With the positive effect of supplementing nucleotide sugar precursors on sialylation, attempts were made to enhance the levels of intracellular nucleotide sugars by supplying these precursors. The addition of nucleotide sugar precursors to cultures treated with inhibitors successfully enhanced the sialylation of Fc-fusion glycoproteins compared to the control culture. This was particularly evident under mild stress conditions and not under relatively severe stress conditions, which were characterized by a high decrease in sialylation. These results suggest that inhibiting autophagy in rCHO cell culture decreases sialylation of Fc-fusion glycoprotein by constraining the availability of intracellular nucleotide sugars. KEY POINTS: •  The autophagy inhibition in rCHO cell culture leads to a significant reduction in the sialylation of Fc-fusion glycoprotein. •  The pool of five intracellular nucleotide sugars remained highly abundant in cells treated with autophagy inhibitors. •  Supplementation of nucleotide sugar precursors effectively restores decreased sialylation, particularly under mild stress conditions but not in relatively severe stress conditions.


Assuntos
Autofagia , Glicoproteínas , Animais , Cricetinae , Células CHO , Cricetulus , Glicoproteínas/genética , Nucleotídeos , Açúcares
6.
J Cataract Refract Surg ; 50(5): 453-459, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38270485

RESUMO

PURPOSE: To investigate the correlated factors of corneal endothelial cell density (ECD) loss and ECD change in implantable collamer lens (ICL) explantation patients. SETTING: Seoul St. Mary's Hospital, Seoul, South Korea. DESIGN: Retrospective analysis. METHODS: The study cohort consisted of 93 eyes from 50 patients who underwent ICL explantation. Correlation analysis was performed to assess the ocular parameters associated with ECD loss, while percentage of ECD change (ΔECD%) was monitored up to 6 months postoperatively. Receiver operating characteristic (ROC) curve was used to set cutoff values of ocular parameters to prevent ECD loss after explantation. RESULTS: In multiple regression analysis, high vaulting, high vaulting/anterior chamber depth (ACD), low anterior chamber angle (ACA), and high iris pigmentations are the significant factors of ECD loss. At postoperative 6 months, 14 eyes (15.1%) had decrease (10.5% loss), 47 eyes (51.0%) were stationary, and 32 eyes (34.4%) had increase (12.7% gain) of ECD. The ROC curve analysis showed that vaulting had the highest area under the curve (AUC = 0.822), followed by vaulting/ACD (AUC = 0.821), ECD (AUC = 0.753), and ACA (AUC = 0.723) (all P < .01). Preoperative ECD showed a sensitivity of 77.6% and specificity of 86.7% in preventing ECD loss after explantation, with a cutoff value of 1722 cells/mm 2 , as determined by ROC curve analysis. CONCLUSIONS: Our study demonstrated that high vaulting is a significant factor in ECD loss among ICL-inserted patients. To prevent continuous ECD loss in ICL patients, close monitoring of ECD and making appropriate decisions regarding explantation may be necessary.

7.
Cornea ; 2024 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-38251908

RESUMO

PURPOSE: The purpose of this study was to describe a new surgical technique for deep anterior lamellar keratoplasty. METHODS: All pupils in the recipient eyes were dilated preoperatively. Vertical grooving was performed using a crescent blade with a width of 5 mm and a depth of one-third to half corneal thickness on the temporal side of the limbus. Stromal dissection was performed as close as possible to Descemet membrane by observing the gap between the gold line by retinal reflex and the front edge of the crescent blade. Lamellar dissection was performed along the lamellar plane using corneal dissectors. The ophthalmic viscoelastic device was injected into the intrastromal pocket to separate the anterior and posterior stroma and an anterior corneal lamella was excised. A donor cornea was sutured into the recipient bed. RESULTS: In 18 eyes, none of the patients had Descemet membrane rupture during surgery. The mean postoperative residual stromal thickness was 80 ± 31 µm. The mean central corneal thickness after surgery was 660 ± 69 µm. At the last follow-up, the cornea was cleared in all 18 eyes on slit-lamp examination. CONCLUSIONS: We estimated the residual stromal thickness based on the gap between the gold line by the retinal reflex and crescent blade, and intrastromal lamellar dissection was performed using a smooth corneal dissector. Consequently, the surface of stromal dissection was smooth, and the residual stromal thickness was even.

8.
Korean J Ophthalmol ; 38(1): 64-70, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38148689

RESUMO

PURPOSE: In the present study, we determined the prevalence of obstructive meibomian gland dysfunction (MGD), hyposecretory MGD, grossly normal MG, and hypersecretory MGD in patients with dry eye syndrome using lipid layer thickness (LLT) and MG dropout. METHODS: Eighty-eight patients with dry eye syndrome were included in the study. Patients were categorized into four groups according to the LLT and weighted total meiboscore. The proportion of patients in each group was calculated. The age, sex, Ocular Surface Disease Index, LLT, Schirmer, tear film breakup time, cornea stain, weighted total meiboscore, expressibility, and quality of meibum were compared between the four groups. RESULTS: Fifteen eyes (17.0%) had obstructive MGD, two eyes (2.3%) had hyposecretory MGD, 40 eyes (45.5%) had grossly normal MG, and 17 eyes (19.3%) had hypersecretory MGD. The obstructive MGD group was younger than the grossly normal MG group. In obstructive MGD, the ratio of men to women was higher than that of the other groups. However, Ocular Surface Disease Index, Schirmer, tear film breakup time, and corneal stain did not show statistically significant differences between the four groups. The meibum expressibility of the hyposecretoy MGD group was worse than those of the other groups. The meibum expressibility of the hyposecretoy MGD group was poor than those of the obstructive and hypersecretory MGD group. CONCLUSIONS: This categorization was expected to help determine the best treatment method for dry eye syndrome, according to the MG status.


Assuntos
Síndromes do Olho Seco , Disfunção da Glândula Tarsal , Masculino , Humanos , Feminino , Disfunção da Glândula Tarsal/diagnóstico , Glândulas Tarsais/diagnóstico por imagem , Estudos Retrospectivos , Síndromes do Olho Seco/diagnóstico , Lágrimas , Lipídeos
9.
Clin Ophthalmol ; 17: 3353-3363, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37941777

RESUMO

Purpose: This study assessed post-market clinical outcomes of the Clareon monofocal intraocular lens (IOL) preloaded in the AutonoMe Delivery System in a real-world setting of Korean patients. Methods: This prospective, multicenter, single-arm study in Korea was conducted from July 2020 to December 2021. Patients were ≥20 years old with unilateral or bilateral cataracts who received Clareon IOLs (CNA0T0) preloaded in an automated injector system. Best corrected distance visual acuity (BCDVA) and uncorrected distance visual acuity (UCDVA) were evaluated under photopic conditions. Surgeon delivery system preference was assessed using a survey questionnaire. Glistenings, surface haze, adverse events, posterior capsule opacification (PCO), and Nd:YAG capsulotomy rates were also assessed during the 12-month postoperative follow-up. Results: Mean ± SD monocular BCDVA was 0.02 ± 0.11 and 0.00 ± 0.10 logMAR at 1 month and 12 months, respectively. BCDVA of 0.2 logMAR or better was achieved by 94.4% and 99.1% of eyes at 1 month and 12 months after implantation, respectively. Mean monocular UCDVA was 0.11 ± 0.14 and 0.07 ± 0.13 logMAR at 1 month and 12 months, respectively. UCDVA of 0.3 logMAR or better was achieved by 97.4% of eyes at 12 months after implantation. Preparation of the automated injector system was rated as "very easy" or "easy" and CNA0T0 IOL delivery was rated as "very controllable" or "controllable" by all surgeons. Only grade 0 glistenings and no surface haze were observed during the 12-month follow-up. No clinically significant PCO or Nd:YAG capsulotomy were reported throughout the study; clinically nonsignificant PCO was reported in 23% of eyes. Conclusion: This 12-month real-world study of the CNA0T0 IOL and the automated injector system demonstrated excellent visual outcomes and high surgeon satisfaction.

10.
Small ; : e2304814, 2023 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-37875646

RESUMO

Owing to the limited electrochemical stability window of carbonate electrolytes, the initial formation of a solid electrolyte interphase and surface film on the negative and positive electrode surfaces by the decomposition of the electrolyte component is inevitable for the operation of lithium secondary batteries. The deposited film on the surface of the active material is vital for reducing further electrochemical side reactions at the surface; hence, the manipulation of this formation process is necessary for the appropriate operation of the assembled battery system. In this study, the thermal decomposition of LiPF6 salt is used as a surface passivation agent, which is autocatalytically formed during high-temperature storage. The thermally formed difluorophosphoric acid is subsequently oxidized on the partially charged high-Ni positive electrode surface, which improves the cycleability of lithium metal cells via phosphorus- and fluorine-based surface film formation. Moreover, the improvement in the high-temperature cycleability is demonstrated by controlling the formation process in the lithium-ion pouch cell with a short period of high-temperature storage before battery usage.

11.
Parasites Hosts Dis ; 61(3): 317-324, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37648238

RESUMO

Standard- and large-sized eggs of Trichuris trichiura were found in the feces of schoolchildren in Yangon, Myanmar during epidemiological surveys and mass deworming with albendazole in 2017-2019. The standard-sized eggs were identified as those of T. trichiura, but it was necessary to exclude the possibility of the large-sized eggs belonging to Trichuris vulpis, a dog whipworm. We conducted morphological and molecular studies to determine the species of the 2 types of Trichuris eggs. Individual eggs of both sizes were isolated from Kato-Katz fecal smears (n=20) and mechanically destroyed using a 23G injection needle. Nuclear DNA was extracted, and the 18S rRNA region was sequenced in 15 standard-sized eggs and 15 large-sized eggs. The average size of standard-sized eggs (T. trichiura) was 55.2×26.1 µm (range: 51.7-57.6×21.3-28.0 µm; n=97), whereas the size of large-sized eggs was 69.3×32.0 µm (range: 65.1-76.4×30.1-34.5 µm; n=20), slightly smaller than the known size of T. vulpis. Regarding standard-sized eggs, the 18S rRNA nucleotide sequences exhibited 100% homology with T. trichiura deposited in GenBank and 88.6-90.5% homology with T. vulpis. Regarding large-sized eggs, the nucleotide sequences showed 99.8-100% homology with T. trichiura in GenBank and 89.6-90.7% homology with T. vulpis. Both standard- and large-sized eggs of Trichuris spp. found in Myanmar schoolchildren during 2017-2019 were morphologically and molecularly confirmed to belong to T. trichiura. The conversion of eggs from smaller to large sizes might be due to anthelmintic treatments with albendazole.


Assuntos
Albendazol , Manduca , Animais , Cães , Mianmar/epidemiologia , RNA Ribossômico 18S/genética , Trichuris/genética , Fezes
12.
ACS Nano ; 17(16): 15931-15941, 2023 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-37548961

RESUMO

For realizing all-solid-state batteries (ASSBs), it is highly desirable to develop a robust solid electrolyte (SE) that has exceptional ionic conductivity and electrochemical stability at room temperature. While argyrodite-type Li6PS5Cl (LPSCl) SE has garnered attention for its relatively high ionic conductivity (∼3.19 × 10-3 S cm-1), it tends to emit hydrogen sulfide (H2S) in the presence of moisture, which can hinder the performance of ASSBs. To address this issue, researchers are exploring approaches that promote structural stability and moisture resistance through elemental doping or substitution. Herein, we suggest using zeolite imidazolate framework-8 as a moisture absorbent in LPSCl without modifying the structure of the SE or the electrode configuration. By incorporating highly ordered porous materials, we demonstrate that ASSBs configured with LPSCl SE display stable cyclability due to effective and long-lasting moisture absorption. This approach not only improves the overall quality of ASSBs but also lays the foundation for developing a moisture-resistant sulfide electrolyte.

13.
Transl Vis Sci Technol ; 12(7): 5, 2023 07 03.
Artigo em Inglês | MEDLINE | ID: mdl-37405796

RESUMO

Purpose: To use the revised model eye to observe and compare how the world is perceived by patients with monofocal intraocular lens (IOL), Eyhance, bifocal IOL, and Symfony, and check its performance. Methods: The new mobile model eye consists of an artificial cornea, an IOL, a wet cell, an adjustable lens tube, a lens tube, an objective lens, a tube lens, and a digital single-lens reflex camera. We collected photographs of distant buildings and streets at night, videos of the focusing process, and videos of United States Air Force resolution target from 6 m to 15 cm and analyzed them quantitatively. Results: In this revised model eye using an objective lens, an artificial cornea similar to the human cornea could be used. Using a digital single-lens reflex camera, high-resolution imaging was possible without an additional computer. Fine focusing was possible using an adjustable lens tube. For monofocal IOL, the contrast modulation was 0.39 at 6 m and decreased consistently. It was nearly 0 as the model eye got closer than 1.6 m. For Eyhance, the contrast modulation was 0.40 at 6 m. It then decreased and increased again. At 1.3 m, it was 0.07 and then decreased again. For Symfony, the contrast modulation was 0.18 at 6 m. Symfony showed the characteristics of a bifocal IOL with low add diopter. Halos (234 pixels) were observed around lights, although smaller than those seen with bifocal IOL (432 pixels). Conclusions: We could objectively observe and compare how patients with monofocal IOL, Eyhance, bifocal IOL, and Symfony perceived the world using this revised model eye. Translational Relevance: Data obtained by this new mobile model eye can be used to help patients select their IOLs before cataract surgeries.


Assuntos
Lentes Intraoculares , Humanos , Acuidade Visual , Visão Ocular
14.
Genes (Basel) ; 14(6)2023 05 23.
Artigo em Inglês | MEDLINE | ID: mdl-37372311

RESUMO

Mammals experience similar stages of embryonic development, birth, infancy, youth, adolescence, maturity, and senescence. While embryonic developmental processes have been extensively researched, many molecular mechanisms regulating the different life stages after birth, such as aging, remain unresolved. We investigated the conserved and global molecular transitions in transcriptional remodeling with age in dogs of 15 breeds, which revealed that genes underlying hormone level regulation and developmental programs were differentially regulated during aging. Subsequently, we show that the candidate genes associated with tumorigenesis also exhibit age-dependent DNA methylation patterns, which might have contributed to the tumor state through inhibiting the plasticity of cell differentiation processes during aging, and ultimately suggesting the molecular events that link the processes of aging and cancer. These results highlight that the rate of age-related transcriptional remodeling is influenced not only by the lifespan, but also by the timing of critical physiological milestones.


Assuntos
Envelhecimento , Transcriptoma , Gravidez , Feminino , Animais , Cães , Envelhecimento/genética , Metilação de DNA/genética , Longevidade , Mamíferos/genética
15.
Ann Med ; 55(1): 2228192, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37354028

RESUMO

PURPOSE: We sought to evaluate the expression of matrix metalloproteinase-9 (MMP-9) in dry eyes treated with 0.05% cyclosporin A and 3.0% diquafosol tetrasodium. METHODS: One-hundred ninety-five eyes of 195 patients with dry eye were divided into three groups as follows: group 1, cyclosporin group (n = 69); group 2, diquafosol group (n = 59); and group 3, artificial tears eyes (n = 67). All eyes were treated and followed up for three months. Schirmer I Test, corneal staining, tear-film break-up time (TBUT), and tear-film MMP-9 content were measured at three months and compared between groups. The expression of MMP-9 was confirmed using a point-of-care test device (InflammaDry®; RPS Diagnostics, Sarasota, FL, USA) and graded as zero to four points. RESULTS: At the third month, MMP-9 expression was lower in group 1 as compared with in groups 2 and 3 (p = 0.020 and 0.006, respectively). The mean MMP-9 grade according to point-of-care testing was also lower in group 1 than in groups 2 or 3 (p = 0.002 and 0.038, respectively). MMP-9 showed a correlation with corneal staining in both groups 1 and 2 (all p < 0.001) and with Schirmer I Test and TBUT in group 1 (p = 0.018 and 0.015, respectively). CONCLUSIONS: MMP-9 expression and grade were lower after treatment with cyclosporin than after treatment with diquafosol in the dry eye disease. Anti-inflammatory treatment can decrease ocular MMP-9 levels in dry eye disease.


MMP-9 expression and grade were lower after treatment with cyclosporin than after treatment with diquafosol in the dry eye disease. Anti-inflammatory treatment can decrease ocular MMP-9 levels in dry eye disease.


Assuntos
Ciclosporina , Síndromes do Olho Seco , Humanos , Ciclosporina/uso terapêutico , Metaloproteinase 9 da Matriz , Síndromes do Olho Seco/tratamento farmacológico , Nucleotídeos de Uracila/uso terapêutico
16.
Small ; 19(28): e2301754, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-36970771

RESUMO

The uncontrollable dendritic growth of metallic lithium during repeated cycling in carbonate electrolytes is a crucial obstacle hindering the practical use of Li-metal batteries (LMBs). Among numerous approaches proposed to mitigate the intrinsic constraints of Li metal, the design of a functional separator is an attractive approach to effectively suppress the growth of Li dendrites because direct contact with both the Li metal surface and the electrolyte is maintained. Here, a newly designed all-in-one separator containing bifunctional CaCO3 nanoparticles (CPP separator) is proposed to achieve the flattening of Li deposits on the Li electrode. Strong interactions between the highly polar CaCO3 nanoparticles and the polar solvent reduces the ionic radius of the Li+ -solvent complex, thus increasing the Li+ transference number and leading to a reduced concentration overpotential in the electrolyte-filled separator. Furthermore, the integration of CaCO3 nanoparticles into the separator induces the spontaneous formation of mechanically-strong and lithiophilic CaLi2 at the Li/separator interface, which effectively decreases the nucleation overpotential toward Li plating. As a result, the Li deposits exhibit dendrite-free planar morphologies, thus enabling excellent cycling performance in LMBs configured with a high-Ni cathode in a carbonate electrolyte under practical operating conditions.

17.
J Appl Res Intellect Disabil ; 36(4): 777-786, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-36896654

RESUMO

BACKGROUND: Single-parent families with children with disabilities need greater attention given the notable increase in their number and their additional difficulties. Single parents in East Asian countries, especially, may face greater risks than their peers elsewhere, given the region's unique cultural background. METHOD: The study used a mixed methods design; we administered a risk assessment survey to 354 families of children with intellectual and developmental disabilities and conducted in-depth interviews with eight single parents. RESULTS: Compared to two-parent families, single-parent families faced greater risks with respect to family relationships, economic status and legal rights. In the interviews, single parents reported a range of challenges, including sole parental responsibilities, poor physical and mental health, social isolation and alienation, the stress of juggling care and work, and difficulty accessing services. CONCLUSION: These findings offer implications for future policy and practices concerning single parents in South Korea.


Assuntos
Deficiência Intelectual , Pais Solteiros , Criança , Humanos , Deficiências do Desenvolvimento , Pais/psicologia , Fatores Socioeconômicos
18.
Artigo em Inglês | MEDLINE | ID: mdl-36753413

RESUMO

Though lithium-ion batteries (LIBs) have seen a meteoric rise in worldwide deployment over the last decade, they should be further advanced in constant demand of higher rate capability and wider temperature adaptability. A solid electrolyte interphase (SEI) is the essential part of LIBs, determining the charge-discharge performance and degradation behavior. Herein, improvement of the SEI properties is achieved by regulating the electrochemical double layer structure with a nonsacrificial electrolyte additive, that is, lithium nonafluoro-1-butanesulfonate. The anion adsorption of the additive affects the decomposition behavior of other additive and solvent species, and the generated SEI at the graphite electrode becomes thinner and more uniform, leading to decreased impedance and finally resulting in improved energy efficiency, power capability, and fast charging performance of the graphite/NCM811 cell. Furthermore, the low-temperature cycleability at -20 °C is considerably enhanced with no dendritic Li metal deposition at the negative electrode surface. A mechanistic study on the interfacial phenomena and the effect is carried out by using various theoretical and experimental methods, such as density functional theory calculations, electrochemical quartz crystal microbalance, and transmission electron microscopy. Consequently, the approach of SEI modification with the nonsacrificial electrolyte additive can be one of the effective ways to advance LIB technology in future.

19.
ACS Appl Mater Interfaces ; 15(8): 10744-10751, 2023 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-36787511

RESUMO

This study validates the beneficial role of residual Li compounds on the surface of Ni-rich cathode materials (LiNixCoyMnzO2, NCM). Residual Li compounds on Ni-rich NCM are naturally formed during the synthesis procedure, which degrades the initial Coulombic efficiency and generates slurry gelation during electrode fabrication in Li-ion batteries (LIBs) using liquid electrolytes. To solve this problem, washing pretreatment is usually introduced to remove residual Li compounds on the NCM surface. In contrast to LIBs, we found that residual Li compounds can serve as a functional layer that suppresses the interfacial side reactions of the NCM in all-solid-state batteries (ASSBs). The formation of resistive phosphate-based compounds from the undesirable side reaction during the initial charging step is suppressed by the residual Li compounds on the surface of the NCM, thereby reducing polarization growth in ASSBs and enhancing rate performances. The advantageous effects of the intrinsic residual Li compounds on the NCM surface suggest that the essential washing process of the NCM for the liquid-based LIB system should be reconsidered for ASSB systems.

20.
ACS Appl Mater Interfaces ; 15(5): 6923-6932, 2023 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-36715535

RESUMO

The lithium (Li) metal anode is highly desirable for high-energy density batteries. During prolonged Li plating-stripping, however, dendritic Li formation and growth are probabilistically high, allowing physical contact between the two electrodes, which results in a cell short-circuit. Engineering the separator is a promising and facile way to suppress dendritic growth. When a conventional coating approach is applied, it usually sacrifices the bare separator structure and severely increases the thickness, ultimately decreasing the volumetric density. Herein, we introduce dielectric silicon oxide with the feature of bi-morphological form, i.e., backbone-covered and backbone-anchored, onto the conventional polyethylene separator without any volumetric change. These functionally vary the Li+ transference number and the ionic conductivity so as to modulate Li-ion solvation and self-scavenging of Li dendrites. The proposed separator paves the way to maximizing the full cell performance of Li/NCM622 toward practical application.

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