EFEITO DAS ATIVIDADES ANTRÓPICAS NA COBERTURA VEGETAL NA RESERVA FLORESTAL DE MECUBÚRI, MOÇAMBIQUE

O estudo foi realizado na Reserva Florestal de Mecubúri, em Moçambiquee, visando avaliar os efeitos das atividades antrópicas sobre a cobertura florestal. Áreas de queimada, agrícola e de exploração florestal foram comparadas com uma área controle em termos de composição e fitossociologia. Em cada área, foram estabelecidas, de maneira sistemática, parcelas quadrangulares de 20 x 20 m, distantes 20 m uma da outra, sendo realizado o levantamento da vegetação adulta e da regeneração. Foram determinados índices de similaridade, diversidade e riqueza. Os resultados indicaram existir dissimilaridade entre as áreas, sendo que as espécies Julbernardia globiflora, Diplorhynchus condylocarpon, Brachystegia utilis, Millettia stuhlmannii, Afzelia quanzensis, Burkea africana e Cussonia arborea destacaram-se em termos de abundância, frequência, dominância, Índice de Valor de Importância (IVI) e regeneração. O maior número de árvores por hectare foi encontrado na área de controle e o menor número foi encontrado na área agrícola. Com base no índice de dispersão de Morisita, a maior parte das espécies distribui-se de forma aleatória e agrupada. A distribuição diamétrica das árvores seguiu o padrão de J-invertido, característico de florestas naturais. As práticas de queimadas, agricultura e exploração florestal contribuem na redução da cobertura florestal na Reserva Florestal de Mecubúri. Palavras-chave: fitossociologia; conservação; desmatamento. The effect of anthropic activities on forest coverage in the Mecubúri Forest Reserve, Mozambique ABSTRACT: The study was carried out in the Mecubúri Forest Reserve, Mozambique, with the purpose of evaluating the effects of human activities on the forest cover. Burning, agricultural and logging areas were compared with a control area in terms of composition and phytosociology. In each area were systematically established 20 x 20 m quadrangular plots, 20 m apart from each other, in which were carried out the survey of adult vegetation and regeneration. The similarity, diversity and richness indices were determined. The results showed that there is dissimilarity between the areas and the species Julbernardia globiflora, Diplorhynchus condylocarpon, Brachystegia utilis, Millettia stuhlmannii, Afzelia quanzensis, Burkea africana e Cussonia arborea stood out in terms of abundance, frequency, dominance, Importance Value Index (IVI) and regeneration. The largest number of trees per hectare was found in the control area, and the smallest number was found in the agricultural area. Based on the Morisita dispersion index, most species have random and clustered distribution. The diametric structure of the trees followed the inverted-j, typical of natural forests. Burning, agriculture and logging contribute to the reduction of forest cover in the Mecubúri Forest Reserve. Keywords: phytosociology; conservation; deforestation.

Linking Microstructural Integrity and Motor Cortex Excitability in Multiple Sclerosis

Motor skills are frequently impaired in multiple sclerosis (MS) patients following grey and white matter damage with cortical excitability abnormalities. We applied advanced diffusion imaging with 3T magnetic resonance tomography for neurite orientation dispersion and density imaging (NODDI), as well as diffusion tensor imaging (DTI) in 50 MS patients and 49 age-matched healthy controls to quantify microstructural integrity of the motor system. To assess excitability, we determined resting motor thresholds using non-invasive transcranial magnetic stimulation. As measures of cognitive-motor performance, we conducted neuropsychological assessments including the Nine-Hole Peg Test, Trail Making Test part A and B (TMT-A and TMT-B) and the Symbol Digit Modalities Test (SDMT). Patients were evaluated clinically including assessments with the Expanded Disability Status Scale. A hierarchical regression model revealed that lower neurite density index (NDI) in primary motor cortex, suggestive for axonal loss in the grey matter, predicted higher motor thresholds, i.e. reduced excitability in MS patients (p = .009, adjusted r² = 0.117). Furthermore, lower NDI was indicative of decreased cognitive-motor performance (p = .007, adjusted r² = .142 for TMT-A; p = .009, adjusted r² = .129 for TMT-B; p = .006, adjusted r² = .142 for SDMT). Motor WM tracts of patients were characterized by overlapping clusters of lowered NDI (p <.05, Cohen’s d = 0.367) and DTI-based fractional anisotropy (FA) (p <.05, Cohen’s d = 0.300), with NDI exclusively detecting a higher amount of abnormally appearing voxels. Further, orientation dispersion index of motor tracts was increased in patients compared to controls, suggesting a decreased fiber coherence (p <.05, Cohen’s d = 0.232). This study establishes a link between microstructural characteristics and excitability of neural tissue, as well as cognitive-motor performance in multiple sclerosis. We further demonstrate that the NODDI parameters neurite density index and orientation dispersion index detect a larger amount of abnormally appearing voxels in patients compared to healthy controls, as opposed to the classical DTI parameter FA. Our work outlines the potential for microstructure imaging using advanced biophysical models to forecast excitability alterations in neuroinflammation.

New score scale for assessing the risk of establishing chronic heart failure with preserved ejection fraction

The aim of the study was to develop a score scale for assessing the high risk of establishing chronic heart failure with preserved ejection fraction (HFpEF), based on echocardiography (EchoCG) evidence.Materials and methods. A clinical and instrumental study of 175 patients, of which 108 (61.7%) women and 67 (38.3%) men, aged 71 [64; 78] years was performed in the 1st City Clinical Hospital in Minsk in 2017–2018. In order to validate the score scale for assessing the risk of HFpEF establishment in 2019–2020 a reproductive clinical and instrumental study of 129 patients was performed at the Minsk Scientific and Practical Center for Surgery, Transplantology and Hematology, of which 55 (42.6%) were men and 74 (57.4%) women aged 65 [58; 70] years. Inclusion criteria: sinus rhythm, essential arterial hypertension, chronic coronary heart disease: atherosclerotic heart disease, past myocardial infarction of left ventricle (LV), after which at least six months have passed, necessary to stabilize the structural and functional parameters of the LV, HFpEF, informed consent of the patient. Exclusion criteria: primary mitral regurgitation, mitral stenosis, mitral valve repair or prosthetics, congenital heart defects, acute and chronic diseases of the kidneys, lungs. EchoCG was performed on ultrasound machines Siemens Acuson S1000 (Germany) and Vivid E9 (GE Healthcare, USA).Results. The developed scale for assessing the risk of establishing HFpEF in a patient with sinus rhythm including the criteria: LV diastolic dysfunction type II – 47 points, deceleration time of peak E of the transmitral blood flow DTE ≤171 ms – 25 points, the speed of early diastolic movement of the septal part of the mitral fibrous ring e'septal ≤7 cm/s – 25 points, LV early diastolic filling index E/е'septal >7.72 – 20 points, index of the end-systolic volume of the left atrium >34.3 ml/m2 – 24 points, has high diagnostic reliability (AUC 0.96, sensitivity (S) 96.6%, specificity (Sp) 83.2%) and reproducibility of results in an examination cohort of patients (AUC 0.99, S 98.8%, Sp 98.0%). A total score > 45 indicates a high probability of HFpEF. If the total score is ≤45, it is recommended to perform 2D Speckle Tracking EchoCG. The leading patho-functional mechanisms for the development of HFpEF are a decrease of LV global systolic longitudinal strain GLSAVG > −18.9% (S 94.9%, Sp 98.0%), GLS of the right ventricle (RV) > −19.9% (S 76.5%, Sp 88.5%), mechanical dispersion with LV mechanical dispersion index > 54.69 ms (S 70.7%, Sp 90.2%), RV mechanical dispersion index > 50.29 msec (S 78.1%, Sp 73.9%) and ventricular dyssynergy with LV global post systolic index >5.59% (S 82.6%, Sp 87.5%), RV global post systolic index > 2.17% (S 84.5%, Sp 69.9%).Conclusions. The use of the developed scale will improve the efficiency of ultrasound imaging of HFpEF.

Abnormal Neurite Density and Orientation Dispersion in Frontal Lobe Link to Elevated Hyperactive/Impulsive Behaviors in Young Adults with Traumatic Brain Injury

Traumatic brain injury is a major public health concern. A significant proportion of individuals experience post-traumatic brain injury behavioral impairments, especially in attention and inhibitory control domains. Traditional diffusion-weighted MRI techniques, such as diffusion tensor imaging, have provided tools to assess white matter structural disruptions reflecting the long-term brain tissue alterations associated with traumatic brain injury. The recently developed neurite orientation dispersion and density imaging is a more advanced diffusion-weighted MRI modality, which provides more refined characterization of brain tissue microstructures by assessing the neurite orientation dispersion and neurite density properties. In this study, we investigated the morphometrical and microstructural alterations at chronic brain injury stage and their relationships with the functional outcomes. Neurite orientation dispersion and density imaging data from 44 young adults with chronic traumatic brain injury (ranging from 18 - 27 years of age; 23 males/21 females) who had no prior-traumatic brain injury history of attention deficits and/or hyperactivity and 45 group-matched normal controls (23 males /22 females) were collected. Maps of fractional anisotropy, neurite orientation dispersion index, and neurite density index were calculated. Vertex-wise and voxel-wise analyses were conducted for gray matter and white matter, respectively. Post-hoc region of interest-based analyses were also performed. Compared to the controls, the group of traumatic brain injury showed significantly increased orientation dispersion index in various gray matter regions and significantly decreased orientation dispersion index in several white matter regions. Brain-behavioral association analyses indicated that the reduced neurite density index of left precentral gyrus and the reduced orientation dispersion index of left superior longitudinal fasciculus were significantly associated with elevated hyperactive/impulsive symptoms in the patients with traumatic brain injury. These findings suggest that traumatic brain injury-induced chronic neurite orientation dispersion alterations of left superior longitudinal fasciculus and left precentral may significantly contribute to post-traumatic brain injury hyperactive/impulsive behaviors in young adults with traumatic brain injury.

Social and Activity Predictors of Novice Specialists’ Professional Self-Concept Development

В статье рассматриваются проблемные вопросы формирования профессионального самоотношения субъекта деятельности на этапе подготовки специалистов в системе высшего образования. Цель исследования — определить особенности профессионального самоотношения будущих специалистов сфер образования, журналистики, лингвистики. Методы исследования: теоретический анализ научной литературы, тестирование, методы описательной статистики, критерий сравнения U Манна — Уитни, дисперсионный факторный анализ. Приведены результаты эмпирического исследования профессионального самоотношения российских и белорусских студентов разных специальностей. Представлены выявленные феномены внутренней конфликтности профессионального самоотношения и противоречия смыслов «Я», связанных с профессией, у будущих специалистов. Осуществлен анализ влияния специфики профессиональной деятельности и ее востребованности в обществе на профессиональное самоотношение будущих специалистов сферы образования (филологи), деловой коммуникации (лингвисты), средств массовой коммуникации (журналисты). Результаты исследования углубляют научные знания о факторах и механизмах профессионального становления личности, а также могут быть использованы специалистами сферы непрерывного профессионального образования в практике системы сопровождения будущих и начинающих педагогов, лингвистов, журналистов. The article treats the problem of developinguniversity students’ professional self-concept. The aim of the research is to identify the peculiarities of professional self-concept in novice teachers, journalists and linguists. Research methods are theoretical analysis, testing, descriptive statistics, the Mann-Whitney U test, dispersion index. The article provides the results of an empirical research of the development of professional self-concept in Russian and Belorussian students. It focuses on the phenomenon of internal contradictions between novice specialists’ professional self-concept and their self-image. The article analyzes the influence of the popularity of a profession and the specifics of professional activities on professional self-concept of novice language teachers, linguists, and journalists. The results of the research give an insight into factors and mechanisms of professional development and can be used by specialists of continuous vocational education as means of providing support to novice teachers, linguists and journalists.

Prediction of the particle size and flow characteristics of powder blends for tableting by near-infrared spectroscopy and chemometrics

The purpose of this research was to apply near-infrared (NIR) spectroscopy in combination with chemometrics to predict particle size and flow characteristics of a meloxicam powder blends for tableting. In order to develop calibration models for particle size (mean particle size, poly-dispersion index), and flow properties (angle of repose and time of flow) prediction, the NIR reflection spectra of different meloxicam powder blends prepared according to an experimental design were analyzed using different preprocessing methods by partial last-square (PLS) regression followed by leaveone-out cross-validation. Very good prediction ability was found for mean particle size, poly-dispersion index, angle of repose, and time of flow in models in whose development no preprocessing spectrum was applied. Also, a good prediction was found preprocessing spectrum such smoothing - moving average for particle size characteristics, and unit vector normalization for powder flow properties. Therefore, NIR-chemometric methods developed in this work can be useful for the prediction of the granulometric properties and parameters related to the flowability of the meloxicam powder blends and may be used as process analytical technology (PAT) tools for process control during meloxicam tablets manufacturing.