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1.
BMC Ophthalmol ; 24(1): 16, 2024 Jan 09.
Artículo en Inglés | MEDLINE | ID: mdl-38195490

RESUMEN

BACKGROUND: The diagnosis of dry eye and other common ophthalmological conditions can be supported using patient reported symptoms, which is increasingly useful in contexts such as telemedicine. We aim to ascertain visual symptoms that differentiate dry eye from cataract, glaucoma, or glaucoma suspects. METHODS: Adults with dry eye, glaucoma, cataract, and suspected glaucoma (controls) completed a questionnaire to rate the frequency and severity of 28 visual symptoms. Univariate, followed by multivariable logistic regression with backward stepwise selection (p < 0.05), determined the individual symptoms and set of symptoms best distinguishing dry eye from each of the other conditions. RESULTS: Mean age of 353 patients (94 glaucoma suspect controls, 79 glaucoma, 84 cataract, and 96 dry eye) was 64.1 years (SD = 14.1); 67% were female and 68% White. Dry eye patients reported more frequent light sensitivity (OR = 15.0, 95% CI = 6.3-35.7) and spots in vision (OR = 2.8, 95% CI = 1.2-6.3) compared to glaucoma suspect controls. Compared to glaucoma patients, dry eye patients experienced more frequent light sensitivity (OR = 9.2, 95% CI = 2.0-41.7), but less frequent poor peripheral vision (OR = 0.2, 95% CI = 0.06-0.7), difference in vision between eyes (OR = 0.09, 95% CI = 0.01-0.7), and missing patches of vision (OR = 0.06, 95% CI = 0.009-0.3). Compared to cataract patients, dry eye patients reported more frequent spots in vision (OR = 4.5, 95% CI = 1.5-13.4) and vision variability across the week (OR = 4.7, 95% CI = 1.2-17.7) and were less likely to report worsening vision (OR = 0.1, 95% CI = 0.03-0.4) and blindness (OR = 0.1, 95% CI = 0.02-0.8). CONCLUSION: Visual symptoms may serve as a complementary tool to distinguish dry eye from various ocular conditions, though the symptoms that best distinguish dry eye differ across comparisons. Differentiating how patients visually perceive common eye diseases may be used in a variety of clinical settings to rule out specific conditions.


Asunto(s)
Catarata , Síndromes de Ojo Seco , Glaucoma , Hipertensión Ocular , Baja Visión , Adulto , Humanos , Femenino , Masculino , Estudios Transversales , Fotofobia , Glaucoma/complicaciones , Glaucoma/diagnóstico , Síndromes de Ojo Seco/diagnóstico , Catarata/complicaciones , Catarata/diagnóstico
2.
J Am Chem Soc ; 145(29): 15997-16014, 2023 Jul 26.
Artículo en Inglés | MEDLINE | ID: mdl-37432784

RESUMEN

The alloyed lead/tin (Pb/Sn) halide perovskites have gained significant attention in the development of tandem solar cells and other optoelectronic devices due to their widely tunable absorption edge. To gain a better understanding of the intriguing properties of Pb/Sn perovskites, such as their anomalous bandgap's dependence on stoichiometry, it is important to deepen the understanding of their chemical behavior and local structure. Herein, we investigate a series of two-dimensional Ruddlesden-Popper (RP) and Dion-Jacobson (DJ) phase alloyed Pb/Sn bromide perovskites using butylammonium (BA) and 3-(aminomethyl)pyridinium (3AMPY) as the spacer cations: (BA)2(MA)n-1PbxSnn-xBr3n+1 (n = 1-3) and (3AMPY)(MA)n-1PbxSnn-xBr3n+1 (n = 1-3) through a solution-based approach. Our results show that the ratio and site preference of Pb/Sn atoms are influenced by the layer thickness (n) and spacer cations (A'), as determined by single-crystal X-ray diffraction. Solid-state 1H, 119Sn, and 207Pb NMR spectroscopy analysis shows that the Pb atoms prefer the outer layers in n = 3 members: (BA)2(MA)PbxSnn-xBr10 and (3AMPY)(MA)PbxSnn-xBr10. Layered 2D DJ alloyed Pb/Sn bromide perovskites (3AMPY)(MA)n-1PbxSnn-xBr3n+1 (n = 1-3) demonstrate much narrower optical band gaps, lower energy PL emission peaks, and longer carrier lifetimes compared to those of RP analogs. Density functional theory calculations suggest that Pb-rich alloys (Pb:Sn ∼4:1) for n = 1 compounds are thermodynamically favored over 50:50 (Pb:Sn ∼1:1) compositions. From grazing-incidence wide-angle X-ray scattering (GIWAXS), we see that films in the RP phase orient parallel to the substrate, whereas for DJ cases, random orientations are observed relative to the substrate.

3.
Inorg Chem ; 62(39): 15971-15982, 2023 Oct 02.
Artículo en Inglés | MEDLINE | ID: mdl-37721531

RESUMEN

Metal sulfide ion exchange materials (MSIEs) are of interest for nuclear waste remediation applications. We report the high stability of two structurally related metal sulfide ion exchange materials, Na2xMg2y-xSn4-yS8 (Mg-NMS) and Na2SnS3 (Na-NMS), in strongly acid media, in addition to the preparation of Na2xNi2y-xSn4-yS8 (Ni-NMS). Their formation progress during synthesis is studied with in-situ methods, with the target phases appearing in <15 min, reaction completion in <12 h, and high yields (75-80%). Upon contact with nitric or hydrochloric acid, these materials topotactically exchange Na+ for H+, proceeding in a stepwise protonation pathway for Na5.33Sn2.67S8. Na-NMS is stable in 2 M HNO3 and Mg-NMS is stable in 4 M HNO3 for up to 4 h, while both NMS materials are stable in 6 M HCl for up to 4 days. However, the treatment of Mg-NMS and Na-NMS with 2-6 M H2SO4 reveals a much slower protonation process since after 4 h of contact both NMS and HMS are present in the solution. The resultant protonated materials, H2xMg2y-xSn4-yS8 and H4x[(HyNay-1)1.33xSn4--1.33x]S8, are themselves solid acids and readily react with and intercalate a variety of organic amines, where the band gap of the resultant adduct is influenced by amine choice and can be tuned within the range of 1.88(5)-2.27(5) eV. The work function energy values for all materials were extracted from photoemission yield spectroscopy in air (PYSA) measurements and range from 5.47 (2) to 5.76 (2) eV, and the relative band alignments of the materials are discussed. DFT calculations suggest that the electronic structure of Na2MgSn3S8 and H2MgSn3S8 makes them indirect gap semiconductors with multi-valley band edges, with carriers confined to the [MgSn3S8]2- layers. Light electron effective masses indicate high electron mobilities.

4.
J Am Chem Soc ; 144(28): 12789-12799, 2022 Jul 20.
Artículo en Inglés | MEDLINE | ID: mdl-35797169

RESUMEN

Lithium chalcogenides have been understudied, owing to the difficulty in managing the chemical reactivity of lithium. These materials are of interest as potential ion conductors and thermal neutron detectors. In this study, we describe three new cubic lithium copper chalcotitanates that crystallize in the P4̅3m space group. LiCu3TiS4, a = 5.5064(6) Å, and LiCu3TiSe4, a = 5.7122(7) Å, represent two members of a new stuffed diamond-type crystal structure, while LiCu3TiTe4, a = 5.9830(7) Å crystallized into a similar structure exhibiting lithium and copper mixed occupancy. These structures can be understood as hybrids of the zinc-blende and sulvanite structure types. In situ powder X-ray diffraction was utilized to construct a "panoramic" reaction map for the preparation of LiCu3TiTe4, facilitating the design of a rational synthesis and uncovering three new transient phases. LiCu3TiS4 and LiCu3TiSe4 are thermally stable up to 1000 °C under vacuum, while LiCu3TiTe4 partially decomposes when slowly cooled to 400 °C. Density functional theory calculations suggest that these compounds are indirect band gap semiconductors. The measured work functions are 4.77(5), 4.56(5), and 4.69(5) eV, and the measured band gaps are 2.23(5), 1.86(5), and 1.34(5) eV for the S, Se, and Te analogues, respectively.

5.
Inorg Chem ; 61(34): 13525-13531, 2022 Aug 29.
Artículo en Inglés | MEDLINE | ID: mdl-35960253

RESUMEN

RbInSn2S6 and CsInSn2S6 are yellow two-dimensional (2D) semiconductors featuring anionic SnS2-type layers of edge-sharing (In/Sn)S6 octahedra. These structures are directly derived from the parent structure of SnS2 by replacement of Sn4+ atoms with A+ and In3+ atoms. The compounds crystallize, isotypic to the ion-exchange material KInSn2S6. They adopt the triclinic space group R3̅m (no. 166). The compounds have similar indirect optical band gaps of 2.31(5) eV for Rb and 2.47(5) eV Cs. The measured work functions for each material are ∼5.38 eV. The density functional theory-calculated effective mass values exhibit strong anisotropy due to the 2D nature of the crystal structures and in the case of CsInSn2S6 for hole carriers along the a, b, and c crystallographic directions are 0.30 m0, 0.34 m0, and 2.54 m0, respectively, while for electrons are 0.06 m0, 0.07 m0, and 0.47 m0, respectively.

6.
Environ Sci Technol ; 56(12): 8590-8598, 2022 06 21.
Artículo en Inglés | MEDLINE | ID: mdl-35647805

RESUMEN

Removal of chromate (CrO42-) and pertechnetate (TcO4-) from the Hanford Low Activity Waste (LAW) is beneficial as it impacts the cost, life cycle, operational complexity of the Waste Treatment and Immobilization Plant (WTP), and integrity of vitrified glass for nuclear waste disposal. Here, we report the application of [MoIV3S13]2- intercalated layer double hydroxides (LDH-Mo3S13) for the removal of CrO42- as a surrogate for TcO4-, from ppm to ppb levels from water and a simulated LAW off-gas condensate of Hanford's WTP. LDH-Mo3S13 removes CrO42- from the LAW condensate stream, having a pH of 7.5, from ppm (∼9.086 × 104 ppb of Cr6+) to below 1 ppb levels with distribution constant (Kd) values of up to ∼107 mL/g. Analysis of postadsorbed solids indicates that CrO42- removal mainly proceeds by reduction of Cr6+ to Cr3+. This study sets the first example of a metal sulfide intercalated LDH for the removal of CrO42-, as relevant to TcO4-, from the simulated off-gas condensate streams of Hanford's LAW melter which contains highly concentrated competitive anions, namely F-, Cl-, CO32-, NO3-, BO33-, NO2-, SO42-, and B4O72-. LDH-Mo3S13's remarkable removal efficiency makes it a promising sorbent to remediate CrO42-/TcO4- from surface water and an off-gas condensate of nuclear waste.


Asunto(s)
Residuos Radiactivos , Cromatos , Hidróxidos , Agua
7.
Am J Ophthalmol ; 269: 84-93, 2024 Jul 06.
Artículo en Inglés | MEDLINE | ID: mdl-38972497

RESUMEN

OBJECTIVE: To compare sociodemographic factors in patients presenting to the emergency department (ED) with emergent and nonemergent eye-related concerns. DESIGN: Cross-sectional multicenter study. SUBJECTS: 60,677 patients with eye-related concerns who visited EDs at Bascom Palmer Eye Institute, Wills Eye Hospital, Massachusetts Eye and Ear, and Johns Hopkins Hospital/Wilmer Eye Institute from January 1, 2019, until December 31, 2019. METHODS: Descriptive statistics were performed using Stata, version 17. MAIN OUTCOME MEASURES: (1) Sociodemographic factors associated with emergent diagnoses, (2) visit patterns across ED settings (ie, standard ED vs eye ED), and (3) the most common emergent and nonemergent diagnoses. RESULTS: A total of 60,677 eye-related ED encounters were included in the study, including 22,434 at Bascom Palmer Eye Institute, 16,124 at Wills Eye Hospital, 15,487 at Massachusetts Eye and Ear, and 6632 at Johns Hopkins Hospital/Wilmer Eye Institute. Most patients had nonemergent diagnoses (56.7%). Males (odds ratio [OR] 1.85, 95% CI 1.79-1.92) were more likely to have an emergent diagnosis than females. Patients with private or employer-based insurance (OR 0.88, 95% CI 0.81-0.96), Medicare (OR 0.80, 95% CI 0.72-0.87), and Medicaid (OR 0.81, 95% CI 0.74-0.89) were all less likely to have an emergent diagnosis than uninsured patients. Those with Veteran or military insurance (OR 1.08, 95% CI 0.87-1.34) were equally likely to have an emergent diagnosis compared with uninsured patients. Non-White Hispanic patients (OR 1.26, 95% CI 1.12-1.42) were more likely to present with an emergent condition than White patients. Patients seen in the standard ED setting were more likely to have emergent diagnoses than those who visited standalone eye EDs (P < .001). The most common emergent diagnoses were corneal abrasion (12.97%), extraocular foreign body (7.61%), and corneal ulcer (7.06%). The most common nonemergent diagnoses were dry eye (7.90%), posterior vitreous detachment (7.76%), and chalazion (6.57%). CONCLUSIONS: ED setting was associated with the acuity of patient diagnoses. Lack of insurance coverage and non-White Hispanic race or ethnicity were associated with emergent eye-related ED visits. Improving access to ophthalmic care in these populations may reduce the incidence of preventable eye emergencies related to untreated chronic conditions. This combined with measures to redirect nonemergent issues to outpatient clinics may alleviate ED overload.

8.
Sci Adv ; 10(31): eado8272, 2024 Aug 02.
Artículo en Inglés | MEDLINE | ID: mdl-39083609

RESUMEN

The growth of layered 2D compounds is a key ingredient in finding new phenomena in quantum materials, optoelectronics, and energy conversion. Here, we report SnP2Se6, a van der Waals chiral (R3 space group) semiconductor with an indirect bandgap of 1.36 to 1.41 electron volts. Exfoliated SnP2Se6 flakes are integrated into high-performance field-effect transistors with electron mobilities >100 cm2/Vs and on/off ratios >106 at room temperature. Upon excitation at a wavelength of 515.6 nanometer, SnP2Se6 phototransistors show high gain (>4 × 104) at low intensity (≈10-6 W/cm2) and fast photoresponse (< 5 microsecond) with concurrent gain of ≈52.9 at high intensity (≈56.6 mW/cm2) at a gate voltage of 60 V across 300-nm-thick SiO2 dielectric layer. The combination of high carrier mobility and the non-centrosymmetric crystal structure results in a strong intrinsic bulk photovoltaic effect; under local excitation at normal incidence at 532 nm, short circuit currents exceed 8 mA/cm2 at 20.6 W/cm2.

9.
J Glaucoma ; 32(8): 631-639, 2023 08 01.
Artículo en Inglés | MEDLINE | ID: mdl-37311015

RESUMEN

PRCIS: Cataract, glaucoma, and glaucoma suspect patients report differing visual symptoms. Asking patients about their visual symptoms may provide useful diagnostic information and inform decision-making in patients with comorbid conditions. PURPOSE: To compare visual symptoms in glaucoma, glaucoma suspect (controls), and cataract patients. METHODS: Glaucoma, cataract, and glaucoma suspect patients at Wilmer Eye Institute responded to a questionnaire rating the frequency and severity of 28 symptoms. Univariate and multivariable logistic regression determined the symptoms that best differentiate each disease pair. RESULTS: In all, 257 patients (mean age: 67.4 ± 13.4 y; 57.2% female; 41.2% employed), including 79 glaucoma, 84 cataract, and 94 glaucoma suspect patients, participated. Compared with glaucoma suspects, glaucoma patients were more likely to report poor peripheral vision (OR 11.29, 95% CI: 3.73-34.16), better vision in 1 eye (OR 5.48, 95% CI: 1.33-22.64), and light sensitivity (OR 4.85, 95% CI: 1.78-13.24), explaining 40% of the variance in diagnosis (ie, glaucoma vs. glaucoma suspect). Compared with controls, cataract patients were more likely to report light sensitivity (OR 3.33, 95% CI: 1.56-7.10) and worsening vision (OR 12.20, 95% CI: 5.33-27.89), explaining 26% of the variance in diagnosis (ie, cataract vs. glaucoma suspect). Compared with cataract patients, glaucoma patients were more likely to report poor peripheral vision (OR 7.24, 95% CI: 2.53-20.72) and missing patches (OR 4.91, 95% CI: 1.52-15.84), but less likely to report worsening vision (OR 0.08, 95% CI 0.03-0.22), explaining 33% of the variance in diagnosis (ie, glaucoma vs. cataract). CONCLUSIONS: Visual symptoms distinguish disease state to a moderate degree in glaucoma, cataract, and glaucoma suspect patients. Asking about visual symptoms may serve as a useful diagnostic adjunct and inform decision-making, for example, in glaucoma patients considering cataract surgery.


Asunto(s)
Extracción de Catarata , Catarata , Glaucoma , Hipertensión Ocular , Humanos , Femenino , Persona de Mediana Edad , Anciano , Anciano de 80 o más Años , Masculino , Fotofobia , Presión Intraocular , Agudeza Visual , Glaucoma/complicaciones , Glaucoma/diagnóstico , Hipertensión Ocular/diagnóstico , Catarata/complicaciones , Catarata/diagnóstico
10.
Am J Ophthalmol ; 254: 36-43, 2023 10.
Artículo en Inglés | MEDLINE | ID: mdl-36965840

RESUMEN

PURPOSE: To characterize the most common ophthalmic conditions seen in the emergency department (ED) DESIGN: Cross-sectional study METHODS: This is a multicenter study of 64,988 patients who visited the Bascom Palmer Eye Institute, Massachusetts Eye and Ear, Wills Eye Hospital, and Johns Hopkins Hospital/Wilmer Eye Institute from January 1, 2019, until December 31, 2019. Demographic and primary diagnosis data were extracted including gender, age, race, ethnicity, insurance type, and ophthalmology consult status. Descriptive statistics were performed on all data using STATA IC 14 (64-bit). RESULTS: A total of 64,988 patients with primary ocular diagnoses were seen across all 4 EDs. The majority of patients were White (63.1%), non-Hispanic/Latino (64.8%), and female (52.3%). The most frequently seen age group was 50-64 years (28.6%). The most common diagnoses across all institutions were conjunctivitis (7.91%), corneal abrasions (5.61%), dry eye (4.49%), posterior vitreous detachments (4.15%), chalazions (3.71%), corneal ulcers (3.01%), subconjunctival hemorrhages (2.96%), corneal foreign bodies (2.94%), retinal detachments (2.51%), and glaucoma (2.12%). Specifically, viral conjunctivitis (2283 of 5139, 44.4%) and primary open-angle glaucoma (382 of 1379, 27.7%) were the most frequently seen subtypes of conjunctivitis and glaucoma. CONCLUSIONS: The most regularly treated ophthalmic conditions in high-volume EDs tend to be lower acuity diagnoses. To combat ED overcrowding and rising health care costs in the United States, we suggest diverting eye-related ED visits to a specialized eye ED service or same-day eye clinic appointment in addition to expanding education for patients and primary care clinicians.


Asunto(s)
Conjuntivitis , Glaucoma de Ángulo Abierto , Glaucoma , Humanos , Femenino , Estados Unidos/epidemiología , Persona de Mediana Edad , Estudios Transversales , Servicio de Urgencia en Hospital
11.
Adv Mater ; 34(44): e2202709, 2022 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-36062547

RESUMEN

Interplay between structural and photophysical properties of metal halide perovskites is critical to their utility in optoelectronics, but there is limited understanding of lattice response upon photoexcitation. Here, 2D perovskites butylammonium lead iodide, (BA)2 PbI4 , and phenethylammonium lead iodide, (PEA)2 PbI4 , are investigated using ultrafast transient X-ray diffraction as a function of optical excitation fluence to discern structural dynamics. Both powder X-ray diffraction and time-resolved photoluminescence linewidths narrow over 1 ns following optical excitation for the fluence range studied, concurrent with slight redshifting of the optical bandgaps. These observations are attributed to transient relaxation and ordering of distorted lead iodide octahedra stimulated mainly by electron-hole pair creation. The c axis expands up to 0.37% over hundreds of picoseconds; reflections sampling the a and b axes undergo one tenth of this expansion with the same timescale. Post-photoexcitation appearance of the (110) reflection in (BA)2 PbI4 would suggest a transient phase transition, however, through new single-crystal XRD, reflections are found that violate glide plane conditions in the reported Pbca structure. The static structure space group is reassigned as P21 21 21 . With this, a nonequilibrium phase transition is ruled out. These findings offer increased understanding of remarkable lattice response in 2D perovskites upon excitation.

12.
Elife ; 102021 04 27.
Artículo en Inglés | MEDLINE | ID: mdl-33904394

RESUMEN

Cortical interneurons establish inhibitory microcircuits throughout the neocortex and their dysfunction has been implicated in epilepsy and neuropsychiatric diseases. Developmentally, interneurons migrate from a distal progenitor domain in order to populate the neocortex - a process that occurs at a slower rate in humans than in mice. In this study, we sought to identify factors that regulate the rate of interneuron maturation across the two species. Using embryonic mouse development as a model system, we found that the process of initiating interneuron migration is regulated by blood vessels of the medial ganglionic eminence (MGE), an interneuron progenitor domain. We identified two endothelial cell-derived paracrine factors, SPARC and SerpinE1, that enhance interneuron migration in mouse MGE explants and organotypic cultures. Moreover, pre-treatment of human stem cell-derived interneurons (hSC-interneurons) with SPARC and SerpinE1 prior to transplantation into neonatal mouse cortex enhanced their migration and morphological elaboration in the host cortex. Further, SPARC and SerpinE1-treated hSC-interneurons also exhibited more mature electrophysiological characteristics compared to controls. Overall, our studies suggest a critical role for CNS vasculature in regulating interneuron developmental maturation in both mice and humans.


Asunto(s)
Movimiento Celular/efectos de los fármacos , Corteza Cerebral/metabolismo , Células Madre Pluripotentes Inducidas/efectos de los fármacos , Interneuronas/efectos de los fármacos , Eminencia Media/irrigación sanguínea , Células-Madre Neurales/efectos de los fármacos , Neurogénesis/efectos de los fármacos , Osteonectina/farmacología , Inhibidor 1 de Activador Plasminogénico/farmacología , Potenciales de Acción , Animales , Corteza Cerebral/embriología , Corteza Cerebral/cirugía , Células Endoteliales/metabolismo , Células HEK293 , Humanos , Células Madre Pluripotentes Inducidas/metabolismo , Células Madre Pluripotentes Inducidas/trasplante , Interneuronas/metabolismo , Interneuronas/trasplante , Péptidos y Proteínas de Señalización Intracelular/genética , Péptidos y Proteínas de Señalización Intracelular/metabolismo , Eminencia Media/embriología , Proteínas de la Membrana/genética , Proteínas de la Membrana/metabolismo , Ratones de la Cepa 129 , Ratones Endogámicos C57BL , Ratones Endogámicos NOD , Ratones Noqueados , Neovascularización Fisiológica , Células-Madre Neurales/metabolismo , Células-Madre Neurales/trasplante , Osteonectina/metabolismo , Comunicación Paracrina , Inhibidor 1 de Activador Plasminogénico/metabolismo , Transducción de Señal
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