ORIENTATION IN SPACE, VESTIBULAR FUNCTION AND OCULAR TRACKING IN THE CHANGED GRAVITATIONAL ENVIRONMENT

2020 ◽  
Vol 54 (6) ◽  
pp. 50-57
Author(s):  
L.N. Kornilova ◽  
Keyword(s):  
Eye Movements ◽  
Spatial Perception ◽  
Sensory Deprivation ◽  
Space Station ◽  
Vestibular Function ◽  
Sensory Stimulation ◽  
The Body ◽  
Fixational Eye Movements ◽  
Ocular Tracking ◽  
The Impact

The paper reports results of the author's sensorimotor physiology studies made under the guidance of I.B.Kozlovskaya. The vestibular function and ocular tracking tests were performed by more than 100 cosmonauts prior to and after long-term missions to the Mir and International space station. Fifty two of them implemented these tests between mission days 129 to 215. We studies orientation illusions, spontaneous eye movements, static vestibulo-ocular response to head turns (static otolith-cervical reflex), dynamic vestibulo-ocular reactions to the head roll about the body axis, precision of fixational eye movements, and smooth tracking. Results of testing in the real changed gravity were compared with the data from 7 to 21-day simulation studies in horizontal dry immersion. The tests revealed 4 forms of vestibular disorders characterized by disturbances of spatial perception, orientation illusions, inversions of vection illusions, weakening of static and strengthening of dynamic vestibulo-ocular reactions, a new visual tracking strategy termed a saccadic approximation, that is the gaze approaches or tracks a target using a series of saccadic movements. In addition, the tests made it possible to specify the impact of afferentation deficit (sensory deprivation) on accuracy of ocular and ocular-manual tracking and validate additional sensory stimulation as a method to counteract the effects of sensory deprivation in real and simulated microgravity.

scholarly journals Microsaccades in applied environments: Real-world applications of fixational eye movement measurements

2020 ◽  
Vol 12 (6) ◽  
Author(s):  
Robert G Alexander ◽  
Stephen L Macknik ◽  
Susana Martinez-Conde
Keyword(s):  
Eye Movements ◽  
Eye Movement ◽  
Athletic Training ◽  
Real World ◽  
High Speed ◽  
Sensory Deprivation ◽  
Assessment Tools ◽  
Current Evidence ◽  
Fixational Eye Movements ◽  
Real World Applications

Across a wide variety of research environments, the recording of microsaccades and other fixational eye movements has provided insight and solutions into practical problems. Here we review the literature on fixational eye movements—especially microsaccades—in applied and ecologically-valid scenarios. Recent technical advances allow noninvasive fixational eye movement recordings in real-world contexts, while observers perform a variety of tasks. Thus, fixational eye movement measures have been obtained in a host of real-world scenarios, such as in connection with driver fatigue, vestibular sensory deprivation in astronauts, and elite athletic training, among others. Here we present the state of the art in the practical applications of fixational eye movement research, examine its potential future uses, and discuss the benefits of including microsaccade measures in existing eye movement detection technologies. Current evidence supports the inclusion of fixational eye movement measures in real-world contexts, as part of the development of new or improved oculomotor assessment tools. The real-world applications of fixational eye movement measurements will only grow larger and wider as affordable high-speed and high-spatial resolution eye trackers become increasingly prevalent.

Eye movements during torso rotations in labyrinthine-defective subjects

1999 ◽  
Vol 9 (6) ◽  
pp. 401-412
Author(s):  
Y.P. Ivanenko ◽  
I. Viaud-Delmon ◽  
A. Sémont ◽  
V.S. Gurfinkel ◽  
A. Berthoz
Keyword(s):  
Eye Movements ◽  
Slow Component ◽  
Low Frequency ◽  
Vestibular Function ◽  
Head Rotation ◽  
Normal Subjects ◽  
The Body ◽  
Vestibular Loss ◽  
Significant Difference ◽  
Oculomotor Responses

The aim of this study was to examine whether the chronic loss of vestibular function modifies perceptual and oculomotor responses during torso rotations in darkness. Subjects (4 patients with complete vestibular loss and 7 healthy volunteers) were seated on a rotating chair. Stimuli consisted of sinusoidal chair rotations ( ± 30 ∘ , 0.1 Hz and 0.011 Hz). We used 2 conditions: space stationary head (neck stimulation) and space stationary head and shoulders (torso stimulation). Horizontal eye deviations and slow component of eye movements were analysed. The results showed that eye movements and perception of head motion in space during neck stimulation were similar to those during torso stimulation both in normal and labyrinthine-defective (LD) subjects. During low-frequency chair rotations (0.011 Hz) all subjects perceived illusory head or head and shoulder rotation in space (as if the lower part of the body was stationary relative to the room) and shifted their gaze in the direction of illusory head rotation. In these conditions there was no significant difference in eye movements between normal and LD subjects. During higher frequency chair rotations (0.1 Hz), LD subjects had significantly larger eye deviations as well as increases in the gain of the slow component of eye movements relative to normals. In these conditions patients mostly perceived illusory head or head and shoulder rotation in space while normal subjects mainly perceived the head as stationary in space. The results indicate that 1) neck and torso rotations can evoke similar ocular responses in LD subjects, 2) the chronic loss of vestibular function modifies the representation of axial body segment motion relative to space.

scholarly journals Fixational eye movement waveforms in amblyopia: Characteristics of fast and slow eye movements

2019 ◽  
Vol 12 (6) ◽  
Author(s):  
Sarah Linda Kang ◽  
Sinem B. Beylergil ◽  
Jorge Otero-Millan ◽  
Aasef Shaikh ◽  
Fatema Ghasia
Keyword(s):  
Visual Acuity ◽  
Eye Movements ◽  
Eye Movement ◽  
Treatment Effectiveness ◽  
Eye Diseases ◽  
Fixational Eye Movements ◽  
Fixation Stability ◽  
Slow Eye Movements ◽  
Fixational Saccades ◽  
The Impact

Fixational eye movements comprise of fast microsaccades alternating with slow inter-saccadic drifts. These physiologic eye movements play an important role in visual perception.  Amblyopic patients are known to have fixation instability, particularly of the amblyopic eye. We examined eye movement abnormalities that contribute to this instability. We found that fixation stability is affected by the presence of fusion maldevelopment nystagmus (FMN). However, some amblyopes can have nystagmus without nasally directed slow phases and reversal in direction of the quick phase on ocular occlusion, features seen in FMN. In patients without nystagmus, we found increased amplitude of fixational saccades and inter-saccadic drifts. We categorized amblyopia patients by type (anisometropic, strabismic, or mixed) and eye movement waveform (no nystagmus, nystagmus without FMN, and FMN). We found specific fast and slow eye movement abnormalities of the fellow and amblyopic eye during fellow, amblyopic and both eyes viewing conditions across eye movement waveforms and types of amblyopia. These eye movement abnormalities can serve as biomarkers that can predict the impact of amblyopia as measured by visual acuity and stereopsis. Evaluation of fixational eye movements in amblyopia could be important to diagnose these common eye diseases and predict treatment effectiveness. 

scholarly journals Eye tracker as an implied social presence: awareness of being eye-tracked induces social-norm-based looking behaviour

2019 ◽  
Vol 12 (2) ◽  
Author(s):  
Hoo Keat Wong ◽  
Ian D. Stephen
Keyword(s):  
Eye Movements ◽  
Eye Movement ◽  
Social Presence ◽  
Recognition Task ◽  
Movement Pattern ◽  
The Body ◽  
Eye Tracker ◽  
Movement Behaviour ◽  
Area Of Interest ◽  
The Impact

Human behaviour is not only influenced by the physical presence of others, but also implied social presence. According to Risko and Kingstone (2011), an eye tracker can represent an implied social presence which could influence individuals’ gaze behaviour. This study examines the impact of awareness of being eye-tracked on eye movement behaviour in a laboratory setting.  During a classic yes/no face recognition task, participants were made to believe that their eye movements were recorded (or not recorded) by eye trackers. Their looking patterns with and without the awareness of being eye-tracked were compared while perceiving social (faces, faces-and-bodies) and non-social (inanimate objects) video stimuli. Area-of-interest (AOI) analysis revealed that misinformed participants (who were not aware that their eye movements were being recorded) looked more at the body (chest and waist) compared to informed participants (who believed they were being eye-tracked), whereas informed participants fixated longer on the mouth and shorter on the eyes of female models than misinformed participants did. These findings highlight the potential impact of an awareness of being eye tracked on one’s eye movement pattern when perceiving a social stimulus. We therefore suggest that even within laboratory settings an eye tracker may function as an implied social presence that leads individuals to modify their eye movement behaviour according to socially-derived inhibitory norms.

The Impact of Shariah Governance and Corporate Governance on the Risk Management Practices: Evidence from Local and Foreign Islamic Banks in Malaysia

2018 ◽  
Vol 15 (2) ◽  
pp. 1-20
Author(s):  
Sabri Embi ◽  
Zurina Shafii
Keyword(s):  
Risk Management ◽  
Corporate Governance ◽  
Management Practices ◽  
Principal Component ◽  
T Test ◽  
The Body ◽  
Primary Data ◽  
Islamic Banks ◽  
Shariah Governance ◽  
The Impact

The purpose of this study is to examine the impact of Shariah governance and corporate governance (CG) on the risk management practices (RMPs) of local Islamic banks and foreign Islamic banks operating in Malaysia. The Shariah governance comprises the Shariah review (SR) and Shariah audit (SA) variables. The study also evaluates the level of RMPs, CG, SR, and SA between these two type of banks. With the aid of SPSS version 20, the items for RMPs, CG, SR, and SA were subjected to principal component analysis (PCA). From the PCA, one component or factor was extracted each for the CG, SR, and RMPs while another two factors were extracted for the SA. Primary data was collected using a self-administered survey questionnaire. The questionnaire covers four aspects ; CG, SR, SA, and RMPs. The data received from the 300 usable questionnaires were subjected to correlation and regression analyses as well as an independent t-test. The result of correlation analysis shows that all the four variables have large positive correlations with each other indicating a strong and significant relationship between them. From the regression analysis undertaken, CG, SR, and SA together explained 52.3 percent of the RMPs and CG emerged as the most influential variable that impacts the RMPs. The independent t-test carried out shows that there were significant differences in the CG and SA between the local and foreign Islamic banks. However, there were no significant differences between the two types of the bank in relation to SR and RMPs. The study has contributed to the body of knowledge and is beneficial to academicians, industry players, regulators, and other stakeholders.

Influence of DAFS-25+polizon composition on blood and functional state of liver of steers at fattening

2020 ◽  
pp. 15-18
Author(s):  
Inna R. Kilmetova ◽  
◽  
Igor A. Rodin ◽  
Nazira I. Khayrullina ◽  
Nikolay G. Fenchenko ◽  
...  
Keyword(s):  
Functional State ◽  
White Blood Cells ◽  
Live Weight ◽  
The Body ◽  
Farm Animals ◽  
Control Group ◽  
Standard Diet ◽  
The Impact ◽  
Experimental Group ◽  
Stimulation Of

Summary. The disbalanced feeding and the uneven distribution of micro- and macroelements in the environment leads to a trace element, in particular hypomelanosis. To accelerate the growth and preservation of young farm animals include in the diet of various biological additives and drugs, which include selenium. For stimulation of weight gain in the livestock industry, as well as for the prevention and treatment of pathological processes in addition to micro - and macrouse amino acids, primarily methionine. The aim of this work was to study the influence of composition of DAFS-25+Polizon on morpho-biochemical parameters of blood and functional state of the liver in fattening bulls of black-motley breed in the conditions of the Republic of Bashkortostan. Experiments using were conducted on bull-calves of black-motley breed of the properties in the properties age from 6 to 15 months. The first experimental group during the experiment was additionally given the composition of DAFS-25+Polizon at a dose of 2 mg/kg, the animals of the control group received a standard diet. To assess the impact of the composition DAFS-25+Polizon on metabolism cattle studied morphological and biochemical indicators of blood and conducted histological examination of the liver. It is established that the use of the composition of DAFS-25+Polizon at a dose of 2 mg/kg increases the number of erythrocytes and hemoglobin in the experimental group and reduces the amount of white blood cells. The serum content of total protein, phosphorus and calcium increases in the group of experimental animals. Microscopic examination of the liver revealed no changes in the structure of the organ and hepatocytes in the experimental group, whereas in the control group hemodynamic disorders and dystrophic changes in liver cells were observed. Thus, the use of the composition DAFS-25+Polizon at a dose of 2 mg/kg of live weight in fattening bulls black-and-white breed contributes to the increase of redox processes in the body, stimulation of metabolism, prevent the development of liver disorders of cellular mechanisms of metabolism, optimizes the structure of the liver, which generally provides higher productivity.

Comparative assessment of morphological mechanisms of maintaining structural liver homeostasis in the dynamics of exposure to coal-rock dust and sodium fluoride on the body

2020 ◽  
pp. 189-194
Author(s):  
M. S. Bugaeva ◽  
O. I. Bondarev ◽  
N. N. Mikhailova ◽  
L. G. Gorokhova
Keyword(s):  
Sodium Fluoride ◽  
Morphological Changes ◽  
The Body ◽  
System Level ◽  
Production Factor ◽  
Coal Rock ◽  
The Impact ◽  
Structural Homeostasis ◽  
Rock Dust

Introduction. The impact on the body of such factors of the production environment as coal-rock dust and fluorine compounds leads to certain shift s in strict indicators of homeostasis at the system level. Maintaining the relative constancy of the internal environment of the body is provided by the functional consistency of all organs and systems, the leading of which is the liver. Organ repair plays a crucial role in restoring the structure of genetic material and maintaining normal cell viability. When this mechanism is damaged, the compensatory capabilities of the organ are disrupted, homeostasis is disrupted at the cellular and organizational levels, and the development of the main pathological processes is noted.The aim of the study is to compare the morphological mechanisms of maintaining structural homeostasis of the liver in the dynamics of the impact on the body of coal-rock dust and sodium fluoride.Materials and methods. Experimental studies were conducted on adult white male laboratory rats. Features of morphological mechanisms for maintaining structural homeostasis of the liver in the dynamics of exposure to coal-rock dust and sodium fluoride were studied on experimental models of pneumoconiosis and fluoride intoxication. For histological examination in experimental animals, liver sampling was performed after 1, 3, 6, 9, 12 weeks of the experiment.Results. The specificity of morphological changes in the liver depending on the harmful production factor was revealed. It is shown that chronic exposure to coal-rock dust and sodium fluoride is characterized by the development of similar morphological changes in the liver and its vessels from the predominance of the initial compensatory-adaptive to pronounced violations of the stromal and parenchymal components. Long-term inhalation of coal-rock dust at 1–3 weeks of seeding triggers adaptive mechanisms in the liver in the form of increased functional activity of cells, formation of double-core hepatocytes, activation of immunocompetent cells and endotheliocytes, ensuring the preservation of the parenchyma and the general morphostructure of the organ until the 12th week of the experiment. Exposure to sodium fluoride leads to early disruption of liver compensatory mechanisms and the development of dystrophic changes in the parenchyma with the formation of necrosis foci as early as the 6th week of the experiment.Conclusions. The study of mechanisms for compensating the liver structure in conditions of long-term exposure to coal-rock dust and sodium fluoride, as well as processes that indicate their failure, and the timing of their occurrence, is of theoretical and practical importance for developing recommendations for the timely prevention and correction of pathological conditions developing in employees of the aluminum and coal industry.The authors declare no conflict of interests.

Experience in the use of double broncholytic therapy in occupational practice

2019 ◽  
pp. 303-307
Author(s):  
Elena A. Beigel ◽  
Natalya G. Kuptsova ◽  
Elena V. Katamanova ◽  
Oksana V. Ushakova ◽  
Oleg L. Lakhman
Keyword(s):  
Quality Of Life ◽  
Personal Data ◽  
The Body ◽  
Step Test ◽  
Aluminum Production ◽  
Chronic Obstructive ◽  
Body Plethysmography ◽  
Occupational Copd ◽  
The Impact

Introduction. Occupational chronic obstructive pulmonary disease (COPD) is one of the leading nosological forms of occupational respiratory disease. Numerous studies have shown high effectiveness of the combination of indacaterol/glycopyrronium (Ultibro®breezhaler®) on the impact on clinical and functional indicators in the treatment of COPD in General practice.The aim of the investigation the case of occupational COPD with the analysis of the dynamics of functional indicators, tolerance to physical load and evaluation of the quality of life of workers engaged in aluminum production by using combination of indacaterol/glycopyrronium.Materials and methods. The random sampling method included 20 men, workers of aluminum production, with the established diagnosis of professional COPD at the age of 40 to 60 years. The survey was conducted (Borg scale, medical Research Council scale (mMRC) and COPD Assessment Test (CAT). Functional methods of studies were conducted: spirometry, body plethysmography, electrocardiography (ECG) and the six-minute stepper test (6-MST).Results. Against the background of 8 weeks of therapy, the volume of forced exhalation for 1 minute (FEV1) increased by 14.7% and amounted to 67.90% of the due values, the forced vital capacity of the lungs (FVC) increased by 11.3% and amounted to 76.95% of the due. According to the body plethysmography (BPG) is set to decrease in residual lung volume on average by 13.4% and static hyperinflation, confirmed by the decrease in functional residual volume (FRV) of 18.8%. During the study period increased physical activity of patients. The average difference between the distance traveled in the six-minute step test before and after treatment was 58.8 m. The analysis of personal data showed that the quality of life of patients improved, the total score in the questionnaire CAT at the beginning of the study was 16.9 points, and after 8 weeks decreased by 63% and amounted to 10.7 points.Conclusions: The Results indicate a positive effect of combination therapy with indacaterol/glycopyrronium on the course and progression of occupational COPD.

Studying Abroad in Nepal: Assessing Impact

2003 ◽  
Vol 9 (1) ◽  
pp. 175-188 ◽  
Author(s):  
Patricia Farrell ◽  
Murari Suvedi
Keyword(s):  
Personal Development ◽  
Intellectual Development ◽  
Longitudinal Research ◽  
Adult Learning Theory ◽  
Academic Program ◽  
The Body ◽  
Study Abroad Programs ◽  
Studying Abroad ◽  
Perceived Impact ◽  
The Impact

The purpose of this study is to analyze the reported or perceived impact of studying in Nepal on student’s academic program, personal development and intellectual development. The study draws upon adult learning theory to analyze survey instrument data, interviews, and case studies to discern the impact of the program on college students and to contribute to the body of longitudinal research on U.S. study abroad programs.

REPEATED LONG-TERM SPACE FLIGHTS: PROTEOMIC INVESTIGATIONS OF COSMONAUTS' BLOOD

2020 ◽  
Vol 54 (5) ◽  
pp. 15-22
Author(s):  
I.M. Larina ◽  
◽  
D.N. Kashirina ◽  
K.S. Kireev ◽  
A.I. Grigoriev ◽  
...  
Keyword(s):  
Bone Structure ◽  
Space Station ◽  
The Body ◽  
Coagulation Cascade ◽  
Chemical Components ◽  
Blood Proteins ◽  
Blood Indices ◽  
Before And After ◽  
Biochemical Indices

We performed the first ever comparative analysis of modifications in the proteome, ionogram and some other blood plasma biochemical indices of 18 male cosmonauts (44 ± 6 years of age) before and after maiden or repeated long-term missions to the Russian segment of the International space station (ISS RS). Levels of proteins, substrates and ions as well as chemical components were measured using the LC-MS-based proteomics and routine biochemical techniques. A total of 256 to 281 indices were investigated with the methods of descriptive statistic, regression analysis, and access to bioinformatics resources. It was shown that blood indices recovery from the maiden and repeated missions reflects changes in the body systems and goes at a various speed. The results of measurements made prior to launch and on day 7 after landing are dependent on the number of missions. The bioinformatics techniques showed that after maiden missions both the mediator proteins of alkaline phosphatase (AP) and blood proteins with reliably changing concentrations are associated with the bio-processes including stress, metabolism and DNA reparation, apoptosis, catabolism and proteolysis. During early re-adaptation from repeated missions the AP level was affected by bone remodeling, phosphorylation, angiogenesis and coagulation cascade suggesting a distinct and urgent trigger of the processes of bone structure and mineralization.

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