Structure dependent optoelectronic properties of monolayer antimonene, bismuthene and their binary compound.

Two-dimensional (2D) antimonene, bismuthene, and their binary compound 2D BiSb possess high spin-orbit coupling (SOC) and potential topological insulator properties upon engineering their structural and chemical properties. Based on many-body first-principles calculations, we show that these materials can exhibit isotropic or anisotropic optoelectronic properties depending on their geometry, i.e. buckled (hb) or asymmetrical washboard (aw) phases. SOC significantly alters their optoelectronic properties, which is predominantly evident in 2D bismuthene. hb-antimonene absorbs light in the visible and partially in the ultraviolet regimes, while the absorption band edge for aw-antimonene, hb- and aw-bismuthene is set at the infrared region, absorption being spread as a broadband optical response through the spectral range. An exciton binding with 0.18 eV energy is detected for hb-bismuthene. Due to their broadband optical response, antimonene, bismuthene, and their binary compound offer possibilities towards applications as 2D materials in solar cells, light-emitting devices, photodetectors and light modulation.

Onset of vertical bonds in new GaN multilayers: beyond van der Waals solids.

A suspended single layer of GaN in a honeycomb structure is stable in a planar geometry. By stacking these GaN layers one can construct bilayers or multilayers, even new three-dimensional (3D) periodic structures. In this study, we clarified how the planar layers are buckled with the onset of vertical Ga-N bonds. Among the four stable phases of bilayer GaN, only one of them maintains the planar geometry, which is bound by weak van der Waals interactions. For the remaining three phases, the layers are buckled with the onset of weak vertical bonds, and attain total energies slightly lower than that of the planar geometry. Structural phase changes, as well as direct-indirect band transitions take place under strain and electrostatic charging. The vertical bonds become shorter in multilayers, and eventually attain the bulk value. Among the stable phases of 3D periodic GaN, only one with a graphite-like structure behaves as a layered, van der Waals solid; whereby others are 3D uniform crystals beyond the van der Waals solid.

The effect of strain and functionalization on the optical properties of borophene.

Following its synthesis, borophene has drawn noticeable attention due to its remarkable intrinsic properties. Understanding and modifying these properties are crucial for implementation of borophene in high-technological applications. In this study, we employed ab initio techniques to examine the variation of the optoelectronic properties of buckled borophene by strain and surface functionalization. We find that the optical response can be tuned by applying compressive/tensile strain and covering the surface with hydrogen and fluorine atoms. It is shown that the variations in optical properties can be correlated with structural deformations and modifications in the electronic band structure. Revealing the tunability of the optical response of borophene can pave the way for its potential uses in various optoelectronic devices.

The effect of a single intravitreal implantation of dexamethasone on the fellow eye in bilateral non-infectious uveitis - case report.

OBJECTIVE: To present the influence of dexamethasone intravitreal implant due to macular edema in non-infectious uveitis in the fellow eye. PATIENTS AND METHODS: A 25-year-old patient with a long history of juvenile arthritis with concomitant recurrent bilateral uveitis, complicated with increases of intraocular pressure and macular edema was treated with a single intravitreal dexamethasone implant into the eye with lower visual acuity. RESULTS: During a 36-month follow-up, the patient's bilateral visual acuity improved. The retinal thickness in both maculae decreased. CONCLUSIONS: Treating macular edema in the course of recurrent uveitis accompanying a systemic disease with dexamethasone depot in vitreous may play a beneficial role also in the fellow eye, when affected. This therapeutic effect in the fellow eye may suggest that the medication can penetrate into the circulatory system and reach such other organs as the fellow eye.

Vitreous amyloidosis in two sisters as the indication of transthyretin-related familial form of systemic amyloidosis among liver transplantation candidates.

Vitreous amyloidosis, a rare condition characteristic of the familial form of systemic amyloidosis with polyneuropathy, is caused by a mutation in the transthyretin (TTR) gene. Herein we have presented 2 sisters with involvement of the vitreous body, which prompted a subsequent diagnosis of the TTR-related, familial form of systemic amyloidosis. Due to the progressive character of the disease and poor prognosis, the patients have been considered for liver transplantation, which at present is the only treatment option for this disease.

Pemphigoid-like ocular lesions in patients with graft-versus-host disease following allogeneic bone marrow transplantation.

We present two patients who developed keratitis sicca and pemphigoid-like symptoms following allogeneic bone marrow transplantation (BMT). The diagnosis of ocular graft-versus-host disease (GvHD) was considerably delayed in both. They were admitted to the reference ophthalmology and posttransplant care departments years after allogeneic BMT, when skin biopsy revealed changes typical for chronic GvHD. In both cases either systemic or local immunosuppressive treatment led to improvement of the clinical condition but did not significantly change patients' quality of life.

The effect of TPP, theophylline and theobromine on the angiogenic activity of mononuclear leucocytes obtained from diabetic patients with proliferative retinopathy.

Tolpa Peat Preparation (TPP) administered in various doses does not influence the ability of mononuclear cells (MNC) obtained from diabetic patients with proliferative retinopathy to induce neovascularization response in H-LIA test. Methylxanthines (theophylline, theobromine) significantly decrease the angiogenic activity of these cells. The therapeutic value of these drugs in proliferative retinopathy should be evaluated.

[Evaluation of pupillary reaction to light flash in patients with retinitis pigmentosa]. / Ocena reakcji zrenicy na blysk swietlny u pacjentów ze zwyrodnieniem barwnikowym siatkówki.

Twenty four patients with retinal pigment dystrophy were subjected to examination of pupillary reaction. Evaluated was the amplitude of pupillary reaction on a standard light flash. The results received were compared with the field changes. It was noted that the amplitude is diminished depending on the changes in the visual field.

[Atypical clinical picture of uveal melanoma]. / Nietypowy obraz kliniczny czerniaka naczyniówki.

Presented is a case of uveal melanoma in the posterior segment of the eye. It has been accompanied by an inflammatory reaction of the anterior segment which made impossible the visual evaluation of the fundus.

[Clinical evaluation of Ocuflur]. / Ocena kliniczna preparatu Ocuflur.

Presented is the initial clinical evaluation of Ocuflur, a compound of Allergan. The influence of the drug on the size of the pupil and the reaction of the pupil to a light flash was tested in volunteer subjects. The efficacy of the drug was tested intraoperatively.