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PURPOSE: To measure the choroidal circulatory parameters Han Chinese children aged 4-14 years from Southwest China, and to explore the relationships between these parameters and age, axial length (AL), and choroidal thickness (ChT). METHODS: 284 eyes from 142 subjects were included in this cross-sectional study. All participants underwent cycloplegic refraction and IOLMaster500 examination. Swept-source optical coherence tomography (SS-OCT) was used to measure submacular choroidal thickness, choroidal vascular volume (CVV), choroidal stromal volume (CSV), choroidal vascularity index (CVI), and CVV/CSV ratio. RESULTS: In this population, the mean CVV was 2.92 ± 0.55 mm3, CSV was 4.69 ± 0.68 mm3, CVI was 38.22 ± 2.46 %, and CVV/CSV ratio was 62.11 ± 6.44 %. Multivariable regression analyses showed that both CVV and CSV were negatively correlated with AL (both P < 0.001) and positively correlated with ChT (both P < 0.001), while age showed no significant correlation with them (both P > 0.05). However, the correlations between CVI and age were not uniform rectilinear. Among participants aged ≤8 years, CVI showed no correlation with age (P > 0.05), while among those aged >8 years, it was positively correlated with age (P < 0.01). CVV/CSV ratio was positively correlated with ChT and age (both P < 0.01). CONCLUSION: After the age of 8, age was positively correlated with CVI. ChT was well correlated with CVI. Longer AL and thinner ChT were associated with reduced CVV and CSV, with CVV decreasing more rapidly than CSV.
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Corioide , Tomografia de Coerência Óptica , Humanos , Criança , Adolescente , Masculino , Pré-Escolar , Feminino , Corioide/irrigação sanguínea , Corioide/diagnóstico por imagem , Estudos Transversais , Tomografia de Coerência Óptica/métodos , China , Comprimento Axial do Olho , População do Leste AsiáticoRESUMO
BACKGROUND: Cardiovascular disease (CVD) is a chronic disease with a serious prognosis, and obesity is a risk factor for CVD. Lipid accumulation product index (LAP) is a new indicator of obesity, waist circumference, and triglycerides were included in the formula, but its association with CVD is inconsistent. Therefore, this study researched the effect of LAP levels on CVD. METHODS: This prospective cohort study was based on the Kailuan cohort. A total of 95,981 participants who completed the first physical examination in 2006 and had no history of CVD or LAP absence were included. The participants were divided into four groups according to the LAP quartile (Q1 - Q4). Up until December 31, 2022, incidence density was calculated for each group. The hazard ratio (HR) and 95% confidence interval (CI) of CVD in each group were calculated by the Cox proportional hazards model. RESULTS: During a median follow-up period of 15.95 years, 9925 incident CVD events occurred (2123 myocardial infarction and 8096 stroke). There were differences in potential confounders among the four groups (P < 0.001). The incidence density and 95% CI of CVD in Q1-Q4 groups were 4.76(4.54, 5.00), 6 0.50(6.24, 6.77), 8.13(7.84, 8.44) and 9.34(9.02, 9.67), respectively. There were significant differences in the survival curves among the four groups by log-rank test (P < 0.001). After adjusting for potential confounders, Cox proportional hazards model results showed that compared with the Q1 group, the HR and 95% CI of CVD in the Q2, Q3, and Q4 groups were1.15(1.08, 1.23), 1.29(1.21, 1.38) and 1.39(1.30, 1.49), respectively. The HR and 95%CI of myocardial infarction were 1.28(1.10, 1.49), 1.71(1.47, 1.98) and 1.92(1.64, 2.23), respectively. The HR and 95%CI of stroke were 1.11 (1.03, 1.19), 1.20 (1.12, 1.29) and 1.28 (1.19, 1.38), respectively. After subgroup analysis by gender, there was no significant interaction (P = 0.169), and the relationship between LAP and CVD in different genders was consistent with the main results. After subgroup analysis by age, there was a significant interaction (P = 0.007), and the association between LAP and CVD in different age groups was consistent with the main results. After subgroup analysis by BMI, there was no significant interaction (P = 0.506), and the association between LAP and CVD in different BMI groups was consistent with the main results. The results remained robust after sensitivity analyses. For each unit increase in ln(LAP), the HR and 95%CI of CVD were 4.07 (3.92, 4.23). CONCLUSION: This study demonstrated that the risk of CVD increased with the increase of LAP level. The risk of CVD in group Q2 - Q4 was 1.15, 1.29, and 1.39 times higher than that in group Q1, respectively. CLINICAL TRIAL REGISTRATION NUMBER: ChiCTR2000029767.
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Most patients with myopia have dry eye, which has been shown to adversely affect ocular symptoms, myopia progression, and quality of life in patients with myopia. Needle prickling has been shown to be effective in providing symptom relief in patients with myopia and dry eye. Press needle is a long-lasting, easy-to-operate, and inexpensive traditional Chinese medicine treatment. The standard practice of needle insertion is very important for the treatment of myopia and dry eye. The specific steps include selecting the appropriate acupoints, piercing them with appropriate needles, and fixing them in the skin or subcutaneously at the acupoints, burying them for 2 days, resting for 1 day; the course of treatment lasts for 2 weeks. Specifically, the following indicators were assessed: uncorrected visual acuity and the ocular surface disease index. This article will explain how to standardize the operation of a press needle in the treatment of myopia and dry eye.
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Terapia por Acupuntura , Síndromes do Olho Seco , Medicina Tradicional Chinesa , Miopia , Humanos , Síndromes do Olho Seco/terapia , Miopia/terapia , Medicina Tradicional Chinesa/métodos , Terapia por Acupuntura/métodos , Terapia por Acupuntura/instrumentação , AgulhasRESUMO
BACKGROUND: Refractive errors are one of the most common ocular conditions among children and adolescents, with myopia showing an increasing prevalence and early onset in this population. Recent studies have identified a correlation between refractive errors and ocular biometric parameters. METHODS: A systematic search was conducted in electronic databases including PubMed, EMBASE, Cochrane Library, Web of Science, and Medline from January 1, 2012, to May 1, 2023. Various ocular biometric parameters were summarized under different refractive states, including axial length (AL), central corneal thickness (CCT), anterior chamber depth (ACD), lens thickness (LT), corneal curvature (CC), Corneal curvature radius (CR),axial length-to-corneal radius ratio (AL/CR ratio), choroidal thickness (ChT), retinal thickness (RT), retinal nerve fiber layer thickness (RNFL), and retinal blood density (VD). The differences in these parameters among different refractive states were analyzed using Stata software with fixed or random-effects models, taking into account the assessed heterogeneity level. RESULTS: This meta-analysis included a total of 69 studies involving 128,178 eyes, including 48,795 emmetropic eyes, 60,691 myopic eyes, 13,983 hyperopic eyes, 2,040 low myopic eyes, 1,201 moderate myopic eyes, and 1,468 high myopic eyes. The results of our study demonstrated that, compared to the control group (emmetropic group), the myopic group and low, moderate, and high myopic groups showed significant increases in AL, AL/CR ratio, and ACD, while the hyperopic group exhibited significant decreases. Compared to the control group, the myopic group had a significantly increase for CC, while CR, CCT, perifoveal RT, subfoveal ChT, foveal ChT, parafoveal ChT, perifoveal (except nasal) ChT, and pRNFL (except temporal) significantly decreased. Compared to the control group, the hyperopic group had a significantly increase for subfoveal ChT, foveal ChT, parafoveal ChT, perifoveal ChT, and nasal pRNFL. Compared to the control group, the low and moderate myopic groups had a significantly decreases for the CCT, parafoveal RT (except nasal), perifoveal RT (except nasal), and pRNFL (except superior and temporal). Compared to the control group, the high myopic group had a significantly increase for CR, while LT, perifoveal ChT (except nasal), parafoveal RT, perifoveal RT, and pRNFL (except temporal) had significant decreased. CONCLUSION: The changes of ocular biometric parameters in children and adolescents are closely related to refractive errors. Ocular biometric parameters devices, as effective non-invasive techniques, provide objective biological markers for monitoring refractive errors such as myopia.
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Hiperopia , Miopia , Erros de Refração , Humanos , Criança , Adolescente , Tomografia de Coerência Óptica/métodos , Retina , Refração Ocular , Biometria/métodosRESUMO
The physical and chemical properties of nanoribbon edges are important for characterizing nanoribbons and applying them in electronic devices, sensors, and catalysts. The mechanical response of molybdenum disulfide nanoribbons, which is an important issue for their application in thin resonators, is expected to be affected by the edge structure, albeit this result is not yet being reported. In this work, the width-dependent Young's modulus is precisely measured in single-layer molybdenum disulfide nanoribbons with armchair edges using the developed nanomechanical measurement based on a transmission electron microscope. The Young's modulus remains constant at ≈166 GPa above 3 nm width, but is inversely proportional to the width below 3 nm, suggesting a higher bond stiffness for the armchair edges. Supporting the experimental results, the density functional theory calculations show that buckling causes electron transfer from the Mo atoms at the edges to the S atoms on both sides to increase the Coulomb attraction.
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Isolable T-shaped planar pnictogen compounds R3Pn were reported more than three decades ago and have been attracting burgeoning interest in recent years; T-shaped planar group 14 anions, isoelectronic to R3Pn, however, are still unknown. Herein, we report the synthesis, full characterization, and reactivity of the first crystalline T-shaped planar group 14 anion 4 bearing a trinitrogen pincer ligand. DFT calculations indicate that the tricoordinate germanium center features both an unoccupied 4p orbital and two lone pairs of electrons. Its electron-rich nature allows for the nucleophilic attack on the methyl iodine giving methyl-substituted complex 5 and facile oxidation of the germanium center by elemental sulfur and selenium to furnish unpresented organic anions bearing terminal Ge[double bond, length as m-dash]Ch (Ch = S or Se) double bonds.
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Chichibabin's hydrocarbon and viologens are among the most famous diradicaloids and organic redox systems, respectively. However, each has its own disadvantages: the instability of the former and its charged species, and the closed-shell nature of the neutral species derived from the latter, respectively. Herein, we report that terminal borylation and central distortion of 4,4'-bipyridine allow us to readily isolate the first bis-BN-based analogues (1 and 2) of Chichibabin's hydrocarbon with three stable redox states and tunable ground states. Electrochemically, both compounds exhibit two reversible oxidation processes with wide redox ranges. One- and two-electron chemical oxidations of 1 afford the crystalline radical cation 1Ë+ and dication 12+, respectively. Moreover, the ground states of 1 and 2 are tunable with 1 as a closed-shell singlet and the tetramethyl-substituted 2 as an open-shell singlet, the latter of which could be thermally excited to its triplet state because of the small singlet-triplet gap.
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The heaviest pnictogen-dipyrromethenes DPMPnCl2 (Pn = Sb, 3; Bi 4), which are direct analogues of boron-dipyrromethene (BODIPY), have been readily prepared and isolated as crystalline solids. Both compounds display green photoluminescence with small full widths at half maximum in toluene. Moreover, the reduction of 3 with sodium metal afforded the cyclic dicoordinate stibinidene 5.
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Anionic oxoboranes and neutral iminoboranes, which are isoelectronic to ketones and alkynes, respectively, have attracted much attention because of their unique structures and various reactivity. However, acid/base-free oxoboranes and iminoboranes are still limited, and readily accessible examples with diverse electronic and steric characteristics are highly desirable. Herein, we report the first syntheses of the acyclic anionic oxoborane 2 and iminoborane 4 bearing two boryl ligands, both of which are acid/base-free. Spectroscopic analysis, X-ray crystallography, and theoretical calculations reveal that 2 and 4 possess a polarized terminal BâO double bond and central B≡N triple bond, respectively.
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Two radical cations of bis-BN-based analogues of Thiele's hydrocarbons were facilely synthesized, fully characterized, and theoretically investigated. One-electron oxidation leads to the reduced bond length alternation and NICS values of the central C4N2 rings, suggesting the decreasing antiaromatic character. The spin density of the radical cations is significantly delocalized over the central linkers with a small contribution from two terminal N-heterocyclic boryl units.
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The first bis(imino)carbazolate pincer ligand supported mononuclear Ga(I) compound LGa: (3) was synthesized and fully characterized. Oxidation of 3 with elemental selenium afforded the dinuclear Ga(III) compound [LGa(µ-Se)]2 (4) bearing two bridging Se atoms. Ligand substitution of Cr(CO)6 with 3 under UV light irradiation afforded the gallylene-chromium complex LGa: â Cr(CO)5 (5). In addition, the attempted synthesis of the aluminium analogue LAl: through reduction of LAlI2 (7) only led to isolation of the dinuclear Al(III) compound (LAlI)2 (8), most probably formed through the C-C coupling of two imino radicals.
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Graphene nanoribbon is an attractive material for nano-electronic devices, as their electrical transport performance can be controlled by their edge structures. However, in most cases, the electrical transport has been investigated only for graphene nanoribbons fabricated on a substrate, which hinders the appearance of intrinsic electrical transport due to screening effects. In this study, we developed special devices based on silicon chips for transmission electron microscopy to observe a monolayer graphene nanoribbon suspended between two gold electrodes. Moreover, with the development of an in-situ transmission electron microscopy holder, the current-voltage characteristics were achieved simultaneously with observing and modifying the structure. We found that the current-voltage characteristics differed between 1.5 nm-wide graphene nanoribbons with armchair and zigzag edge structures. The energy gap of the zigzag edge was more than two-fold larger than that of the armchair edge and exhibited an abrupt jump above a critical bias voltage in the differential conductance curve. Thus, our in-situ transmission electron microscopy method is promising for elucidating the structural dependence of electrical conduction in two-dimensional materials.
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BACKGROUND: Coronavirus disease 2019 (COVID-19) is a global pandemic caused by the Severe Acute Respiratory Syndrome Coronavirus-2 (SARS-CoV-2). There is no specific cure for this disease, and the clinical management mainly depends on supportive treatment. This disease may affect SARS-CoV-2 conjunctivitis. Yuxingcao eye drops is used in treating COVID-19 conjunctivitis in China. METHODS: A comprehensive literature search will be conducted. Two methodological trained researchers will read the title, abstract, and full texts and independently select the qualified literature according to inclusion and exclusion criteria. After assessment of the risk of bias and data extraction, we will conduct meta-analyses for outcomes related to COVID-19 conjunctivitis. The heterogeneity of data will be investigated by Cochrane X and I tests. Then publication bias assessment will be conducted by funnel plot analysis and Egger test. RESULTS: The results of our research will be published in a peer-reviewed journal. CONCLUSION: Our study aims to systematically present the clinical evidence of Yuxingcao eye drops in treating COVID-19 conjunctivitis, which will be of significant meaning for further research and clinical practice. PROSPERO REGISTRATION NUMBER: PROSPERO CRD42020209059.
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COVID-19/complicações , Conjuntivite/tratamento farmacológico , Conjuntivite/etiologia , Medicamentos de Ervas Chinesas/uso terapêutico , Ensaios Clínicos como Assunto , Conjuntivite/virologia , Medicamentos de Ervas Chinesas/administração & dosagem , Medicamentos de Ervas Chinesas/efeitos adversos , Humanos , Soluções Oftálmicas , Pandemias , Projetos de Pesquisa , SARS-CoV-2RESUMO
Investigation of optical properties of Ce3+-activated phosphors is not only of practical importance for various applications but also of fundamental importance for providing a basis to understand relevant properties of other lanthanide ions in the same host. We report herein a combined experimental and theoretical study of optical properties of Ce3+ in Li4SrCa(SiO4)2. Photoluminescence properties of the material prepared by a solid-state reaction method are investigated with excitation energies in the vacuum-ultraviolet (VUV) to ultraviolet (UV) range at low temperatures. The band maxima in the excitation spectra are assigned with respect to 4f â 5d transitions of Ce3+ at the Sr and Ca sites, from comparison between experimental and ab initio predicted transition energies. As a result of the two-site occupation, the material displays luminescence at 300-500 nm with a high thermal quenching temperature (>500 K), consistent with the calculated large gaps (â¼1.40 eV) between the emitting 5d levels and the bottom of the host conduction band. On the basis of experimental and calculated results for Ce3+ in Li4SrCa(SiO4)2, the energy-level diagram for the 4f ground states and the lowest 5d states of all trivalent and divalent lanthanide ions at the Sr and Ca sites of the same host is constructed and discussed in association with experimental findings.
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A series of Ln-doped KSrPO4 (Ln = Ce3+, Eu3+, Eu2+, Pr3+) phosphors are prepared through a high-temperature solid-state method. The KSrPO4 compound is confirmed to possess a ß-K2SO4 structure with the Pnma group by Rietveld refinement, and the temperature-dependent lattice parameters are investigated with the powder X-ray diffraction results at different temperatures. Ce3+ and Eu3+ ions are introduced to probe the crystal field strength (CFS) and the lanthanide site symmetry by using VUV-UV-vis spectroscopy. The temperature-dependent luminescence properties of KSrPO4: Ce3+/Eu2+ exhibit an excellent thermal stability of Ce3+/Eu2+ luminescence. Based on the VUV-UV-vis spectra of Ce3+ and Eu3+ doped KSrPO4, the vacuum referred binding energy (VRBE) scheme is constructed to understand the redox properties of Eu, the 5d energy levels of Pr3+ and the thermal quenching characteristics of Ce3+ and Eu2+ luminescence.
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A series of Ce3+-doped (Ca,Sr)2Al2SiO7 phosphors with different Ce3+ and Ca2+/Sr2+ concentrations were prepared by a high temperature solid-state reaction technique. To get insight into the structure-luminescence relationship, the impact of incorporation of Sr2+ on structure of (Ca,Sr)2Al2SiO7 was first investigated via Rietveld refinement of high quality X-ray diffraction (XRD) data, and then the VUV-UV excitation and UV-vis emission spectra of (Ca,Sr)2Al2SiO7:Ce3+ were collected at low temperature. The results reveal that the crystal structure evolution of (Ca,Sr)2Al2SiO7:Ce3+ has influences on band gaps and Ce3+ luminescence properties including 4f-5di (i = 1-5) transition energies, radiative lifetime, emission intensity, quantum efficiency, and thermal stability. Moreover, the influence of Sr2+ content on the energy of Eu3+-O2- charge-transfer states (CTS) in (Ca,Sr)2Al2SiO7:Eu3+ was studied in order to construct vacuum referred binding energy (VRBE) schemes with the aim to further understand the luminescence properties of (Ca,Sr)2Al2SiO7:Ce3+. Finally, X-ray excited luminescence (XEL) spectra were measured to evaluate the possibility of (Ca,Sr)2Al2SiO7:Ce3+ as a scintillation material.
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Based on the experimentally synthesized dye JZ145, we designed a series of novel D-A-π-A dyes SPL201-SPL211 with different π-conjugated bridges and a new auxiliary withdrawing group for highly efficient dye-sensitized solar cells (DSSCs) using density functional theory (DFT) and time-dependent DFT(TDDFT). The molecular structures, energy levels, absorption spectra, light-harvesting efficiency (LHE), driving force of injection(ΔGinj) and regeneration(ΔGreg), electron dipole moment (µnormal) and lifetime of the first excited state(τ) were all scrutinized in details. Results reveal that the additional withdrawing group A2 and the π-conjugated group di-η-hexyl-substituted cyclopentadithiophene (CPDT) are more promising functional groups for the organic dyes with D-A-π-A structure. We further designed SPL212 and SPL213 by employing indoline group as donor, the above screened functional groups as π-conjugated bridge and additional withdrawing group, biscarbodithiolic acid and dicyanovinyl sulfonic acid groups as acceptor group. We found that SPL212 exhibits not only a higher molar extinction coefficient with an increment of 30.8%, larger excited state lifetime and an obvious redshift of 201nm but also a broader absorption spectrum covering the entire visible range even up to near-IR of 1200nm compared to JZ145. So, SPL212 can be used as a promising candidate for DSSCs. In addition, the results also prove that biscarbodithiolic acid may be more favorable than dicyanovinylsulfonic acid as acceptor group in DSSCs.
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Developing highly efficient organic dyes with panchromatic visible light harvesting for dye-sensitized solar cells (DSSCs) is still one of the most important scientific challenges. Here, we design a series of phenothiazine derivative organic dyes with donor-π-acceptor (D-π-A) structure using density functional theory (DFT) and time-dependent DFT (TDDFT) based on experimentally synthesized typical SH-6 organic dyes. Results indicate that the newly designed BUCT13 - BUCT30 dyes show smaller HOMO-LUMO energy gaps, higher molar extinction coefficients and obvious redshifts compared to the SH-6 dye, and the maximum absorption peaks of eight dyes are greater than 650 nm among the newly designed dyes. In particular, BUCT27 exhibits a 234 nm redshift and the maximum molar extinction coefficient with an increment of about 80% compared to the SH-6 dye. BUCT19 exhibits not only a 269 nm redshift and higher molar extinction coefficient with an increment of about 50% compared to the SH-6 dye, but the extremely broad absorption spectrum covering the entire visible range up to the near-IR region of 1200 nm. It is expected that this work can provide a new strategy and guidance for the investigation of these dye-sensitized devices.
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A high color purity red emission is obtained in Pr(3+) activated NaGdTiO(4) (NGTP) materials. The International Commission on Illumination (CIE) chromaticity coordinates are calculated to be 0.663, 0.337, which are very close to the National Television System Committee (NTSC) red color 0.67, 0.34. The good color coordinates are due to intensive quenching of (3)P(0)-(3)H(4) emissions through the metal-to-metal intervalence charge transfer. Interestingly, the high color purity red emitting is observed not only under UV light excitation but also under low-voltage cathode ray excitation. The results indicate that NGTP may have a potential application in field emission displays.