Simulation of exciton spectra in disordered supramolecular polymers: exciton localization in indolenine squaraine hexamers.

In order to understand the effects of disorder and defects in oligomers and polymers on the localization of excitons, we investigated the spectral properties of the squaraine B hexamer using long range corrected tight-binding TDDFT (lc-TDDFTB) and Frenkel-exciton model based calculations. Employing classical molecular dynamics, the indolenine squaraine hexamers helix was propagated in DCM and acetone to obtain ensembles of realistic structures, which naturally exhibit considerable disorder. The trajectories together with several model squaraine systems were studied to show the profound effects of disorder in the superstructure and disorder of the local monomer geometry on optical properties like absorption and exciton localization.

Perifocal edema and glymphatic system dysfunction: quantitative assessment based on diffusion tensor magnetic resonance imaging.

Background: Pathogenesis of peritumoral cerebral edema is unclear and potentially associated with glymphatic system dysfunction. Diffusion tensor MRI (DT-MRI) with analysis of ALPS (Analysis along the Perivascular Space) index may be valuable for assessment of edema. This approach visualizes fluid flow along perivascular spaces of deep cerebral veins.

Factors influencing peritumoral edema in meningiomas: CT- and MRI-based quantitative assessment.

Unlabelled: Background. Meningiomas may be accompanied by peritumoral edema. Incidence and pathogenesis of edema are nor clearly established.

High-order pump-probe and high-order two-dimensional electronic spectroscopy on the example of squaraine oligomers.

Time-resolved spectroscopy is commonly used to study diverse phenomena in chemistry, biology, and physics. Pump-probe experiments and coherent two-dimensional (2D) spectroscopy have resolved site-to-site energy transfer, visualized electronic couplings, and much more. In both techniques, the lowest-order signal, in a perturbative expansion of the polarization, is of third order in the electric field, which we call a one-quantum (1Q) signal because in 2D spectroscopy it oscillates in the coherence time with the excitation frequency.

Enriched Environment Induces Sex-Specific Changes in the Adult Neurogenesis, Cytokine and miRNA Expression in Rat Hippocampus.

An enriched environment stimulates adult hippocampal plasticity, but the exact cellular and molecular mechanisms are complex, and thus a matter of debate. We studied the behavior and hippocampal neurogenesis in adult male and female Wistar rats that were housed in an enriched environment (EE) for two months. Both EE males and females performed better than control animals in a Barnes maze, meaning that EE enhances spatial memory.

The Effect of Long-Term Emotional and Painful Stress on the Expression of Proinflammatory Cytokine Genes in Rats with High and Low Excitability of the Nervous System.

Stress plays an important role in the pathogenesis of anxiety and depressive disorders. Neuroinflammation is considered as one of the mechanisms by which stress alters the molecular and cellular plasticity in the nervous tissue and thus entails CNS dysfunction. The contribution of genetically determined features of the nervous system to the development of post-stress neuroinflammation has not been sufficiently studied.

Separating single- from multi-particle dynamics in nonlinear spectroscopy.

Quantum states depend on the coordinates of all their constituent particles, with essential multi-particle correlations. Time-resolved laser spectroscopy is widely used to probe the energies and dynamics of excited particles and quasiparticles such as electrons and holes, excitons, plasmons, polaritons or phonons. However, nonlinear signals from single- and multiple-particle excitations are all present simultaneously and cannot be disentangled without a priori knowledge of the system.

[Periventricular changes following hydrocephalus: quantitative MR-based assessment of tissue characteristics].

Objective: To study tissue characteristics of periventricular white matter in patients with open hydrocephalus using DWI MRI and their correlations with CSF flow parameters.

Material And Methods: MRI was performed in 55 patients (35 women and 20 men) with open normal pressure hydrocephalus, as well as 16 patients with malignant occlusive hydrocephalus and interstitial edema (control group). We determined the correlations between severity of hydrocephalus, periventricular lesions and CSF flow parameters considering MR data.

[Comparison of resting state and task-based functional MRI in preoperative mapping in patients with brain gliomas].

Objective: To analyze and compare the results of cerebral cortex mapping with task-based (tb-fMRI) and resting-state functional MRI in patients with glioma of eloquent cortical areas.

Material And Methods: There were 55 patients (24 men and 31 women aged 24 - 74 years, median 39) with glial tumors. In 26 patients, the tumor was located in motor areas.

[Machine learning for resting state fMRI-based preoperative mapping: comparison with task-based fMRI and direct cortical stimulation].

Objective: To develop a system for preoperative prediction of individual activations of motor and speech areas in patients with brain gliomas using resting state fMRI (rsfMRI), task-based fMRI (tb-fMRI), direct cortical stimulation and machine learning methods.

Material And Methods: Thirty-three patients with gliomas (19 females and 14 males aged 19 - 540) underwent DCS-assisted resection of tumor (19 ones with lesion of motor zones and 14 patients with lesions of speech areas). Awake craniotomy was performed in 14 cases.

[Endoscopic transnasal approach in surgical treatment of petrous temporal bone cholesteatoma extending towards the clivus. Three clinical observations and literature review].

Unlabelled: Petrous temporal bone Cholesteatoma is widely described in the literature and accounts for up to 9% of all neoplasms of this localization. These cholesteatomas rarely spread towards the clivus. Isolated clival cholesteatomas are described only as single cases.

Catalytic Hydroconversion of 5-HMF to Value-Added Chemicals: Insights into the Role of Catalyst Properties and Feedstock Purity.

5-hydroxymethylfurfural (HMF) is an important bio-derived platform molecule that is generally obtained from hexoses via acid-catalyzed dehydration. It can be effectively transformed into a variety of value-added derivatives, thus being an ideal candidate for fossil replacement. Both HMF oxidation and hydrogenation processes enable the synthesis of numerous chemicals, monomers for polymerization, and biofuel precursors.

Fluorescence band exchange narrowing in a series of squaraine oligomers: energetic vs. structural disorder.

The influence of oligosquaraine chain length on the energies and shape of absorption and emission bands and the exciton coherence length is studied in CHCl where the oligomers adopt a random coil structure. From the observed fluorescence band narrowing an effective coherence length of N = 2.5 was estimated for the nonamer.

Application of HRGS for forensic characterization of uranium oxides, pure uranium metals and uranium alloys.

A nondestructive iterative method for uranium-bearing material characterization with HRGS developed earlier in Burdeinyi et al. (2020) is applied to determine matrix densities, uranium mass fraction and uranium isotope masses of uranium ore, UO and UO powders, fuel elements in the form of UO microspheres, uranium metal and uranium alloys. It is shown that UO powders with uranium mass fraction of about 84% can be distinguished from the powders of UO with uranium mass fraction of about 87%; uranium products in the form of liquid or loose powder with matrix density of 0.

Correction: From wavelike to sub-diffusive motion: exciton dynamics and interaction in squaraine copolymers of varying length.

[This corrects the article DOI: 10.1039/C9SC04367E.].

Solvent Induced Helix Folding of Defined Indolenine Squaraine Oligomers.

A protecting group strategy was employed to synthesise a series of indolenine squaraine dye oligomers up to the nonamer. The longer oligomers show a distinct solvent dependence of the absorption spectra, that is, either a strong blue shift or a strong red shift of the lowest energy bands in the near infrared spectral region. This behaviour is explained by exciton coupling theory as being due to H- or J-type coupling of transition moments.

Ultrafast Energy Transfer Dynamics in a Squaraine Heterotriad.

A squaraine heterotriad consisting of three different covalently linked squaraine chromophores was synthesized, and its absorption spectra were interpreted in terms of Kasha's exciton coupling theory. Using the exciton couplings derived from model dyads (ca. 700 cm) as the input, we were able to predict the exciton state energies of the heterotriad.

Feasibility of generalised diffusion kurtosis imaging approach for brain glioma grading.

Purpose: An accurate differentiation of brain glioma grade constitutes an important clinical issue. Powerful non-invasive approach based on diffusion MRI has already demonstrated its feasibility in glioma grade stratification. However, the conventional diffusion tensor (DTI) and kurtosis imaging (DKI) demonstrated moderate sensitivity and performance in glioma grading.

A new nondestructive iterative method for forensics characterization of uranium-bearing materials by HRGS.

In addition to the isotopic composition of a radioactive material, the high-resolution gamma spectrometry (HRGS) allows one to quantify physical characteristics of the material, which are important for nuclear forensics. A quantitative assessment of these characteristics requires two input parameters: the sample density and the mass fraction of radioactive material in the matrix. A method is proposed to determine these parameters provided that the enrichment and the total mass of the material are known.

[Breast cancer metastasis into a giant hormone-inactive pituitary adenoma adenoma. (Clinical case and literature review)].

Brain metastases of various types of cancer are diagnosed in 8-10% of all cancer patients. In the world literature, only 30 cases of cancer metastasis to the pituitary adenoma are described. This article presents yet another observation of a patient with breast cancer metastasis into the hormone-inactive pituitary adenoma at the Burdenko neurosurgical center, Russia The patient underwent endoscopic endonasal transsphenoid removal of the neoplasm.

[Transsphenoid extirpation of pituitary adenomas in patients with McCune-Albright syndrome (two cases from practice and literature review)].

Introduction: McCune-Albright Syndrome is a rare genetic disease characterized by the formation of fibrous osteodysplasia foci of various localization, including the bones of skull base. Having a gross lesion of the main bone body and the simultaneous formation of the pituitary adenoma, its transnasal removal becomes very difficult.

Material And Methods: Two clinical observations are presented where at patients with the classic manifestation of McCune-Albright syndrome we were able to successfully remove somatotropinomas with endoextrasellar growth.

From wavelike to sub-diffusive motion: exciton dynamics and interaction in squaraine copolymers of varying length.

Exciton transport and exciton-exciton interactions in molecular aggregates and polymers are of great importance in natural photosynthesis, organic electronics, and related areas of research. Both the experimental observation and theoretical description of these processes across time and length scales, including the transition from the initial wavelike motion to the following long-range exciton transport, are highly challenging. Therefore, while exciton dynamics at small scales are often treated explicitly, long-range exciton transport is typically described phenomenologically by normal diffusion.

[Correlation of intracranial pressure and diameter of the sheath of the optic nerve by computed tomography in severe traumatic brain injury].

Background: Noninvasive techniques to evaluate intracranial pressure (ICP) are important for everyday practice in intensive care and neurosurgery departments. CT data can be used to evaluate the optic nerve sheath diameter (ONSD) and, indirectly, the ICP value. The ONSD value is an additional criterion in deciding on invasive monitoring of ICP.