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Purpose: Posttraumatic stress disorder (PTSD) is still-underdiagnosed and often accompanied by other psychiatric disorders affecting treatment and outcomes. Case description: Here we present a case report of a 28-year-old female patient with comorbid PTSD, major depressive disorder (MDD), and anorexia nervosa (AN). The patient had been treated with various medications and attended trauma-focused psychotherapy. Because none of these treatments yielded satisfying improvement, the patient was referred for electroconvulsive therapy (ECT). We had to overcome challenges such as the patient's false assumptions about ECT, the simultaneous use of benzodiazepines and the management of the side effects of ECT. The symptoms of MDD and PTSD improved after 12 treatment sessions. Comment: Our report suggests that ECT may be a safe and effective method for treating patients with PTSD and comorbid MDD and AN.
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One-dimensional (1D) perovskites (perovskitoids) occupy an important place among modern semiconducting materials, offering design flexibility together with a wide range of properties. However, most such materials have a large bandgap, which limits their application in photovoltaics. Here, we present a new 1D hybrid perovskite containing the functional cation aminophenyl viologen (APhV). Similar to other materials from the viologen perovskite family, aminophenyl viologen iodidoplumbate(II) (APhV[Pb2I6]·2NMP) exhibits a broad absorption with a narrow and direct bandgap of 1.66 eV, which was calculated from the experimental data and is supported also by our first-principles simulations. Close contact between electron-rich inorganic chains and electron-accepting viologen molecules suggests charge transfer within the hybrid, which is also visible in the density of states. Considering its reasonable thermal stability, aminophenyl viologen iodidoplumbate can find a wide application in photovoltaics.
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Due to the drastic required thermodynamical requirements, a photoelectrode material that can function as both a photocathode and a photoanode remains elusive. In this work, we demonstrate for the first time that, under simulated solar light and without co-catalysts, donor-acceptor conjugated acetylenic polymers (CAPs) exhibit both impressive oxygen evolution (OER) and hydrogen evolution (HER) photocurrents in alkaline and neutral medium, respectively. In particular, poly(2,4,6-tris(4-ethynylphenyl)-1,3,5-triazine) (pTET) provides a benchmark OER photocurrent density of ~200â µA cm-2 at 1.23â V vs. reversible hydrogen electrode (RHE) at pHâ 13 and a remarkable HER photocurrent density of ~190â µA cm-2 at 0.3â V vs. RHE at pHâ 6.8. By combining theoretical investigations and electrochemical-operando Resonance Raman spectroscopy, we show that the OER proceeds with two different mechanisms, with the electron-depleted triple bonds acting as single-site OER in combination with the C4-C5 atoms of the phenyl rings as dual sites. The HER, instead, occurs via an electron transfer from the tri-acetylenic linkages to the triazine rings, which act as the HER active sites. This work represents a novel application of organic-based materials and contributes to the development of high-performance photoelectrochemical catalysts for the solar fuels' generation.
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Repulsive and long-range exciton-exciton interactions are crucial for the exploration of one-dimensional (1D) correlated quantum phases in the solid state. However, the experimental realization of nanoscale confinement of a 1D dipolar exciton has thus far been limited. Here, we demonstrate atomically precise lateral heterojunctions based at transitional-metal dichalcogenides (TMDCs) as a platform for 1D dipolar excitons. The dynamics and transport of the interfacial charge transfer excitons in a type II WSe2-WS1.16Se0.84 lateral heterostructure were spatially and temporally imaged using ultrafast transient reflection microscopy. The expansion of the exciton cloud driven by dipolar repulsion was found to be strongly density dependent and highly anisotropic. The interaction strength between the 1D excitons was determined to be â¼3.9 × 10-14 eV cm-2, corresponding to a dipolar length of 310 nm, which is a factor of 2-3 larger than the interlayer excitons at two-dimensional van der Waals vertical interfaces. These results suggest 1D dipolar excitons with large static in-plane dipole moments in lateral TMDC heterojunctions as an exciting system for investigating quantum many-body physics.
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PRCIS: Subgrouping of angle closure mechanisms based on the swept-source optical coherence tomography images may help to identify the predominant underlying anatomic mechanism, evaluate personal treatment, and improve the better outcomes. PURPOSE: The purpose of this study was to evaluate changes in anterior segment parameters in Caucasian eyes with different angle closure mechanisms before and after laser peripheral iridotomy (LPI). METHODS: Sixty-six subjects underwent swept-source optical coherence tomography (CASIA, Tomey Corporation) angle imaging in the dark before and 7 days after LPI. On the basis of the baseline swept-source optical coherence tomography images, the eyes were categorized into 4 angle closure mechanisms, namely pupillary block (PB), plateau iris configuration (PIC), thick peripheral iris (TPI), and large lens vault (LLV). Sixteen out of 128 cross-sectional images (11.25 degrees apart) per volume scan were selected for analysis. We used a generalized estimating equation to compare quantitative parameters among angle closure mechanisms and between before and after LPI after adjusting the intereye correlation. RESULTS: The mean age of subjects was 67.7±9.2 years, with the majority being female (82.2%). One hundred twenty-nine eyes (67 primary angle closure suspects, 34 primary angle closure, and 28 primary angle closure glaucoma) were categorized into PB (n=71, 55%), PIC (n=40, 31%), TPI (n=14, 10.9%), and LLV (n=4, 3.1%). Anterior chamber depth was the shallowest in the LLV, followed by TPI, PB, and PIC group at baseline. Widening of the angle and reduction of the iris curvature (IC) due to LPI were observed in all groups (all P <0.01). When compared to the PB group, the LPI-induced angle widening in the TPI group was significantly less even though the iris curvature reduction in the TPI group was greater (all P <0.05). CONCLUSIONS: In patients with angle closure, anterior segment morphology and LPI-induced angle widening were different among the various angle closure mechanisms.
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Glaucoma de Ángulo Cerrado , Terapia por Láser , Láseres de Estado Sólido , Trastornos de la Pupila , Humanos , Femenino , Persona de Mediana Edad , Anciano , Masculino , Segmento Anterior del Ojo/diagnóstico por imagen , Iridectomía/métodos , Presión Intraocular , Glaucoma de Ángulo Cerrado/diagnóstico , Glaucoma de Ángulo Cerrado/cirugía , Iris/cirugía , Terapia por Láser/métodos , Tomografía de Coherencia Óptica/métodos , GonioscopíaRESUMEN
Few-layer organic nanosheets are becoming increasingly attractive as two-dimensional (2D) materials due to their precise atomic connectivity and tailor-made pores. However, most strategies for synthesizing nanosheets rely on surface-assisted methods or top-down exfoliation of stacked materials. A bottom-up approach with well-designed building blocks would be the convenient pathway to achieve the bulk-scale synthesis of 2D nanosheets with uniform size and crystallinity. Herein, we have synthesized crystalline covalent organic framework nanosheets (CONs) by reacting tetratopic thianthrene tetraaldehyde (THT) and aliphatic diamines. The bent geometry of thianthrene in THT retards the out-of-plane stacking, while the flexible diamines introduce dynamic characteristics into the framework, facilitating nanosheet formation. Successful isoreticulation with five diamines with two to six carbon chain lengths generalizes the design strategy. Microscopic imaging reveals that the odd and even diamine-based CONs transmute to different nanostructures, such as nanotubes and hollow spheres. The single-crystal X-ray diffraction structure of repeating units indicates that the odd-even linker units of diamines introduce irregular-regular curvature in the backbone, aiding such dimensionality conversion. Theoretical calculations shed more light on nanosheet stacking and rolling behavior with respect to the odd-even effects.
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MA2 Z4 monolayers form a new class of hexagonal non-centrosymmetric materials hosting extraordinary spin-valley physics. While only two compounds (MoSi2 N4 and WSi2 N4 ) are recently synthesized, theory predicts interesting (opto)electronic properties of a whole new family of such two-dimensional (2D) materials. Here, the chemical trends of band gaps and spin-orbit splittings of bands in selected MSi2 Z4 (M = Mo, W; Z = N, P, As, Sb) compounds are studied from first-principles. Effective Bethe-Salpeter-equation-based calculations reveal high exciton binding energies. Evolution of excitonic energies under external magnetic field is predicted by providing their effective g-factors and diamagnetic coefficients, which can be directly compared to experimental values. In particular, large positive g-factors are predicted for excitons involving higher conduction bands. In view of these predictions, MSi2 Z4 monolayers yield a new platform to study excitons and are attractive for optoelectronic devices, also in the form of heterostructures. In addition, a spin-orbit induced bands inversion is observed in the heaviest studied compound, WSi2 Sb4 , a hallmark of its topological nature.
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The synthesis of homogeneous covalent organic framework (COF) thin films on a desired substrate with decent crystallinity, porosity, and uniform thickness has great potential for optoelectronic applications. We have used a solution-processable sphere transmutation process to synthesize 300 ± 20 nm uniform COF thin films on a 2 × 2 cm2 TiO2-coated fluorine-doped tin oxide (FTO) surface. This process controls the nucleation of COF crystallites and molecular morphology that helps the nanospheres to arrange periodically to form homogeneous COF thin films. We have synthesized four COF thin films (TpDPP, TpEtBt, TpTab, and TpTta) with different functional backbones. In a close agreement between the experiment and density functional theory, the TpEtBr COF film showed the lowest optical band gap (2.26 eV) and highest excited-state lifetime (8.52 ns) among all four COF films. Hence, the TpEtBr COF film can participate in efficient charge generation and separation. We constructed optoelectronic devices having a glass/FTO/TiO2/COF-film/Au architecture, which serves as a model system to study the optoelectronic charge transport properties of COF thin films under dark and illuminated conditions. Visible light with a calibrated intensity of 100 mW cm-2 was used for the excitation of COF thin films. All of the COF thin films exhibit significant photocurrent after illumination with visible light in comparison to the dark. Hence, all of the COF films behave as good photoactive substrates with minimal pinhole defects. The fabricated out-of-plane photodetector device based on the TpEtBr COF thin film exhibits high photocurrent density (2.65 ± 0.24 mA cm-2 at 0.5 V) and hole mobility (8.15 ± 0.64 ×10-3 cm2 V-1 S-1) compared to other as-synthesized films, indicating the best photoactive characteristics.
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In cove-edged zigzag graphene nanoribbons (ZGNR-Cs), one terminal CH group per length unit is removed on each zigzag edge, forming a regular pattern of coves that controls their electronic structure. Based on three structural parameters that unambiguously characterize the atomistic structure of ZGNR-Cs, we present a scheme that classifies their electronic state (i.e., if they are metallic, topological insulators, or trivial semiconductors) for all possible widths N, unit lengths a, and cove position offsets at both edges b, thus showing the direct structure-electronic structure relation. We further present an empirical formula to estimate the band gap of the semiconducting ribbons from N, a, and b. Finally, we identify all geometrically possible ribbon terminations and provide rules to construct ZGNR-Cs with a well-defined electronic structure.
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The ß-emitting 99 Tc isotope is a high-yield fission product in 235 U and 239 Pu nuclear reactors, raising special concern in nuclear waste management due to its long half-life and the high mobility of pertechnetate (TcO4 - ). Under the conditions of deep nuclear waste repositories, Tc is retained through biotic and abiotic reduction of TcO4 - to compounds like amorphous TcO2 â xH2 O precipitates. It is generally accepted that these precipitates have linear (Tc(µ-O)2 (H2 O)2 )n chains, with trans H2 O. Although corresponding Tc-Tc and Tc-O distances have been obtained from extended X-ray absorption fine structure (EXAFS) spectroscopy, this structure is largely based on analogy with other compounds. Here, we combine density-functional theory with EXAFS measurements of fresh and aged samples to show that, instead, TcO2 â xH2 O forms zigzag chains that undergo a slow aging process whereby they combine to form longer chains and, later, a tridimensional structure that might lead to a new TcO2 polymorph.
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Single-atom catalysts (SACs), as promising alternatives to Pt-based catalysts, suffer from the limited choice of center metals and low single-atom loading. Here, we report a pentacoordinated Zr-based SAC with nontrivial axial O ligands (denoted O-Zr-N-C) for oxygen reduction reaction (ORR). The O ligand downshifts the d-band center of Zr and confers Zr sites with stable local structure and proper adsorption capability for intermediates. Consequently, the ORR performance of O-Zr-N-C prominently surpasses that of commercial Pt/C, achieving a half-wave potential of 0.91â V vs. reversible hydrogen electrode and outstanding durability (92 % current retention after 130-hour operation). Moreover, the Zr site shows good resistance towards aggregation, enabling the synthesis of Zr-based SAC with high loading (9.1â wt%). With the high-loading catalyst, the zinc-air battery (ZAB) delivers a record-high power density of 324â mW cm-2 among those of SAC-based ZABs.
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PtSe2 is one of the most promising materials for the next generation of piezoresistive sensors. However, the large-scale synthesis of homogeneous thin films with reproducible electromechanical properties is challenging due to polycrystallinity. It is shown that stacking phases other than the 1T phase become thermodynamically available at elevated temperatures that are common during synthesis. It is shown that these phases can make up a significant fraction in a polycrystalline thin film and discuss methods to characterize them, including their Seebeck coefficients. Lastly, their gauge factors, which vary strongly and heavily impact the performance of a nanoelectromechanical device are estimated.
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The potential of metal-organic frameworks (MOFs) for applications in optoelectronics results from a unique combination of interesting photophysical properties and straightforward tunability of organic and inorganic units. Here, it is demonstrated that using MOF approach chromophores can be assembled into well-ordered 1D arrays using metal-oxo strands as lead structure, and the resulting porphyrinic rows exhibit unique photophysical properties and allow the realization of highly sensitive photodetectors. A porphyrinic MOF thin film, In-TCPP surface-coordinated MOF thin films with [021] orientation is fabricated using a layer-by-layer method, from In(NO3)3 and TCPP (5,10,15,20-(4-carboxyphenyl)porphyrin). Detailed experimental and theoretical analysis reveals that the assembly yields a structure where In-oxo strands running parallel to the substrate fix the chromophoric linkers to yield 1D arrays of porphyrins. The frontier orbitals of this highly anisotropic arrangement are localized in these columnar arrangements of porphyrins and result in high photoactivity, which is exploited to fabricate a photodetector with record (as compared to other organic materials) responsivity in visible regime of 7.28 × 1014 Jones and short rise/fall times (0.07/0.04 s). This oriented MOF thin film-based high-sensitive photodetector provides a new avenue to use inorganic, stable lead structures to assemble organic semiconductors into regular arrays, thus creating a huge potential for the fabrication of optoelectronic devices.
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van der Waals heterostructures are currently the focus of intense investigation; this is essentially due to the unprecedented flexibility offered by the total relaxation of lattice matching requirements and their new and exotic properties compared to the individual layers. Here, we investigate the hybrid transition-metal dichalcogenide/2D perovskite heterostructure WS2/(PEA)2PbI4 (where PEA stands for phenylethylammonium). We present the first density functional theory (DFT) calculations of a heterostructure ensemble, which reveal a novel band alignment, where direct electron transfer is blocked by the organic spacer of the 2D perovskite. In contrast, the valence band forms a cascade from WS2 through the PEA to the PbI4 layer allowing hole transfer. These predictions are supported by optical spectroscopy studies, which provide compelling evidence for both charge transfer and nonradiative transfer of the excitation (energy transfer) between the layers. Our results show that TMD/2D perovskite (where TMD stands for transition-metal dichalcogenides) heterostructures provide a flexible and convenient way to engineer the band alignment.
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In van der Waals heterostructures of 2D transition-metal dichalcogenides (2D TMDCs) electron and hole states are spatially localized in different layers forming long-lived interlayer excitons. Here, the influence of additional electron or hole layers on the electronic properties of a MoS2 /WSe2 heterobilayer (HBL), which is a direct bandgap material, is investigated from first principles. Additional layers modify the interlayer hybridization, mostly affecting the quasiparticle energy and real-space extend of hole states at the Γ and electron states at the Q valleys. For a sufficient number of additional layers, the band edges move from K to Q or Γ, respectively. Adding electron layers to the HBL leads to more delocalized K and Q states, while Γ states do not extend much beyond the HBL, even when more hole layers are added. These results suggest a simple and yet powerful way to tune band edges and the real-space extent of the electron and hole wave functions in TMDC heterostructures, potentially affecting strongly the lifetime and dynamics of interlayer excitons.
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PRCIS: Laser peripheral iridotomy (LPI) widened the iridocorneal angle and flattened the iris circumferentially in Caucasian eyes and baseline refractive error, lens vault, and iris volume play a significant role in the angle widening. PURPOSE: The purpose of this study was to investigate circumferential angle widening and iris changes after LPI using swept-source optical coherence tomography (SS-OCT) in Caucasian eyes with the use of novel anterior segment parameters. MATERIALS AND METHODS: A total of 130 eyes (68 primary angle-closure suspect, 34 primary angle closure, and 28 primary angle-closure glaucoma eyes) of 66 subjects underwent 360-degree SS-OCT (SS-1000 CASIA) angle imaging and gonioscopy in the dark before and 7, 30, 90 days after LPI. For each eye, 16 frames (11.25 degree apart) were selected for analysis from 128 cross-sectional images, and novel 2-dimensional and 3-dimensional anterior segment parameters namely angle opening distance area (AODA) and the trabecular-iris space volume (TISV) 750 µm from the scleral spur, as well as iris parameters such as iris thickness (IT750 and IT2000), iris curvature, and iris curvature area were measured for each image. RESULTS: AODA and TISV were significantly increased and the iris curvature and iris curvature area were significantly decreased at days 7, 30, and 90 after LPI when compared with their baseline (all P<0.001) but there was no significant change in the IT750 and IT2000 (all P>0.05). The multivariable linear regression model showed a significant association of ΔAODA with refractive error (ß=-0.23, P=0.013), lens vault (ß=2.8, P=0.007), and iris volume (ß=-0.11, P=0.027) after adjusting for age and sex. CONCLUSIONS: LPI widened the iridocorneal angle and flattened the iris circumferentially in Caucasian eyes in this study. Baseline refractive error, lens vault, and iris volume play a significant role in the circumferential angle widening by LPI.
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Glaucoma de Ángulo Cerrado , Terapia por Láser , Segmento Anterior del Ojo/diagnóstico por imagen , Glaucoma de Ángulo Cerrado/cirugía , Gonioscopía , Humanos , Presión Intraocular , Iridectomía , Iris/diagnóstico por imagen , Iris/cirugía , Rayos Láser , Estudios Prospectivos , Tomografía de Coherencia ÓpticaRESUMEN
Highly ordered titanium oxide films grown on a Pt3Ti(111) alloy surface were utilized for the controlled immobilization and tip-induced electric field-triggered electronic manipulation of nanoscopic W3O9 clusters. Depending on the operating conditions, two different stable oxide phases, z'-TiO x and w'-TiO x , were produced. These phases show a strong effect on the adsorption characteristics and reactivity of W3O9 clusters, which are formed as a result of thermal evaporation of WO3 powder on the complex TiO x /Pt3Ti(111) surfaces under ultra-high vacuum conditions. The physisorbed tritungsten nano-oxides were found as isolated single units located on the metallic attraction points or as supramolecular self-assemblies with a W3O9-capped hexagonal scaffold of W3O9 units. By applying scanning tunneling microscopy to the W3O9-(W3O9)6 structures, individual units underwent a tip-induced reduction to W3O8. At elevated temperatures, agglomeration and growth of large WO3 islands, which thickness is strongly limited to a maximum of two unit cells, were observed. The findings boost progress toward template-directed nucleation, growth, networking, and charge state manipulation of functional molecular nanostructures on surfaces using operando techniques.
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BACKGROUND: To evaluate the relationship between bleb vascularity and surgical outcome one year after mitomycin C (MMC) augmented trabeculectomy. METHODS: This was a prospective study of 51 eyes of 44 patients after MMC-augmented primary trabeculectomy with follow-up of 12 months. The total vessel area of a bleb was measured with ImageJ software on color photographs of the bleb on day 1 and 14, then months 1, 3, 6 and 12 after trabeculectomy. Blebs were classified clinically as successful (intraocular pressure (IOP) ≤ 18 mmHg and a >30% reduction in IOP without antiglaucoma medications or additional surgical interventions) or failed. Linear regression analysis was performed to determine the correlation of bleb vascularity with IOP and outcome. RESULTS: At 1 year, 40 eyes (78.4%) were classified as successful and 11 eyes (21.6%) as failed. The mean bleb vascularity at 1, 3 and 12 months after surgery was significantly higher in failed blebs (16.31% vs. 13.01%, p = 0.005, 14.93% vs. 10.15%, p = 0.001, 8.99% vs. 6.37%, p = 0.011, respectively). There were no significant differences in mean bleb vascularity at 1 and 14 days postoperatively in successful and failed blebs. The results revealed a significant association between vessel area at 1 and 3 months after trabeculectomy with IOP at 6 months postoperatively (p = 0.005 and p = 0.009, respectively). CONCLUSIONS: In this prospective study, we demonstrated a strong relationship between bleb vascularity and the surgical outcomes of trabeculectomy. Vascularity of the filtering bleb during early postoperative period was not correlated with IOP or success of trabeculectomy at one year. Increased bleb vascularity 1, 3 and 12 months after trabeculectomy appears to predict surgical failure at 1 year after trabeculectomy.
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Detailed derivation of the analytical, reciprocal-space approach of Hessian calculation within the self-consistent-charge density-functional based tight-binding framework (SCC-DFTB) is presented. This approach provides an accurate and efficient way for obtaining the SCC-DFTB Hessian of periodic systems. Its superiority with respect to the traditional numerical force differentiation method is demonstrated for doped graphene, graphene nanoribbons, boron-nitride nanotubes, bulk zinc-oxide, and other systems.
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A promising strategy for new electrically conductive coordination polymers is the combination of d10 metal ions, which tolerate short metal···metal distances, with dithiolene linkers, known for their "non-innocent" redox behavior. This study explores the coordination chemistry of 2,3-pyrazinedithiol (H2pdt) toward Cu+ and Ag+ ions, highlighting similarities and differences. The synthetic approach, starting with the fully protonated ligand, allowed the isolation of a homoleptic bis(dithiolene) complex with formal CuI atoms, [Cu(H2pdt)2]Cl (1). This complex was further transformed to a 1D coordination polymer with short metal···metal distances, 1D[Cu(Hpdt)] (2Cu). The larger Ag+ ion directly built up a very similar coordination polymer, 1D[Ag(Hpdt)] (2Ag), without any appearance of an intermediate metal complex. The coordination polymer 1D[Cu(H2pdt)I] (4), like complex 1, bears fully protonated H2pdt ligands in their dithione form. Upon heating, both compounds underwent auto-oxidation coupled with a dehydrogenation of the ligand to form the open-shell neutral copper(II) complex [Cu(Hpdt)2] (3) and the coordination polymer 1D[Cu2I2(H2pdt)(Hpdt)] (5), respectively. For all presented compounds, crystal structures are discussed in-depth. Furthermore, properties of 1, 3, and those of the three 1D coordination polymers, 2Ag, 2Cu, and 4, were investigated by UV-vis-NIR spectroscopy, cyclic voltammetry, and variable-temperature magnetic susceptibility, and direct current (dc)-conductivity measurements. The experimental results are compared and discussed with the aid of DFT simulations.