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Myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) is a complex multifactorial disease that causes increasing morbidity worldwide, and many individuals with ME/CFS symptoms remain undiagnosed due to the lack of diagnostic biomarkers. Its etiology is still unknown, but increasing evidence supports a role of herpesviruses (including HHV-6A and HHV-6B) as potential triggers. Interestingly, the infection by these viruses has been reported to impact the expression of microRNAs (miRNAs), short non-coding RNA sequences which have been suggested to be epigenetic factors modulating ME/CFS pathogenic mechanisms. Notably, the presence of circulating miRNAs in plasma has raised the possibility to use them as valuable biomarkers for distinguishing ME/CFS patients from healthy controls. Thus, this study aimed at determining the role of eight miRNAs, which were selected for their previous association with ME/CFS, as potential circulating biomarkers of the disease. Their presence was quantitatively evaluated in plasma from 40 ME/CFS patients and 20 healthy controls by specific Taqman assays, and the results showed that six out of the eight of the selected miRNAs were differently expressed in patients compared to controls; more specifically, five miRNAs were significantly upregulated (miR-127-3p, miR-142-5p, miR-143-3p, miR-150-5p, and miR-448), and one was downmodulated (miR-140-5p). MiRNA levels directly correlated with disease severity, whereas no significant correlations were observed with the plasma levels of seven pro-inflammatory cytokines or with the presence/load of HHV-6A/6B genome, as judged by specific PCR amplification. The results may open the way for further validation of miRNAs as new potential biomarkers in ME/CFS and increase the knowledge of the complex pathways involved in the ME/CFS development.

Maxillary sinus augmentation is a commonly used procedure for the placement of dental implants. However, the use of natural and synthetic materials in this procedure has resulted in postoperative complications ranging from 12% to 38%. To address this issue, we developed a novel calcium deficient HA/β-TCP bone grafting nanomaterial using a two-step synthesis method with appropriate structural and chemical parameters for sinus lifting applications. We demonstrated that our nanomaterial exhibits high biocompatibility, enhances cell proliferation, and stimulates collagen expression. Furthermore, the degradation of β-TCP in our nanomaterial promotes blood clot formation, which supports cell aggregation and new bone growth. In a clinical trial involving eight cases, we observed the formation of compact bone tissue 8 months after the operation, allowing for the successful installation of dental implants without any early postoperative complications. Our results suggest that our novel bone grafting nanomaterial has the potential to improve the success rate of maxillary sinus augmentation procedures.

By developing several different methods to present 3-dimensional (3D) images, a demand to investigate the interaction with the human visual system is inevitable. Although current estimates centered on stereoscopic depth perception, still our knowledge is low about the effect of non-stereoscopic displays on the visual cortex, both at the sensory and cognitive brain reactions. In this study, we investigated the cortical activity correlated with a volumetric multiplanar image perception in both 3D and 2D by analyzing the event-related potentials (ERPs) and Power Spectral Density (PSD) analysis. The study was designed based on two conditions. The first condition (3D test) was arranged by presenting four constant angular size rings in which one of them was closer to the subjects. The second condition (2D test) was done by adding trials with the same ring features while all rings were presented on the same plane. A volumetric multiplanar display was employed to present the non-stereoscopic visual targets. Moreover, the brain signal was recorded via an EEG amplifier and then analyzed by the EEGLAB toolbox on MATLAB. Event-related potentials (ERPs) studied in three time windows, (50-100ms), (100-200ms), and (200-450ms), correspond with the N1, P2, and P3 components of ERPs. The analysis showed no significant differences in amplitude between two conditions across five occipital and parietal electrodes, even though there was only a significant difference in latency of the P3 component on the Pz electrode. Furthermore, the Power Spectral Density (PSD) of the alpha and the beta oscillation was analyzed. The analysis does not show significant differences between 3D and 2D tasks; nevertheless, slightly higher alpha and beta activities seemed in 2D visualization. To conclude, 3D image representation on the volumetric multiplanar display has no more sensory or cognitive load on the human brain that responded equally to both visual conditions with a slight difference in latency of the P3 component. Moreover, depth perception on a multiplanar display requires less brain activity.

Precise perception of three-dimensional (3D) images is crucial for a rewarding experience when using novel displays. However, the capability of the human visual system to perceive binocular disparities varies across the visual field meaning that depth perception might be affected by the two-dimensional (2D) layout of items on the screen. Nevertheless, potential difficulties in perceiving 3D images during free viewing have received only a little attention so far, limiting opportunities to enhance visual effectiveness of information presentation. The aim of this study was to elucidate how the 2D layout of items in 3D images impacts visual search and distribution of maintaining attention based on the analysis of the viewer’s gaze. Participants were searching for a target which was projected one plane closer to the viewer compared to distractors on a multi-plane display. The 2D layout of items was manipulated by changing the item distance from the center of the display plane from 2° to 8°. As a result, the targets were identified correctly when the items were displayed close to the center of the display plane, however, the number of errors grew with an increase in distance. Moreover, correct responses were given more often when subjects paid more attention to targets compared to other items on the screen. However, a more balanced distribution of attention over time across all items was characteristic of the incorrectly completed trials. Thus, our results suggest that items should be displayed close to each other in a 2D layout to facilitate precise perception of 3D images and considering distribution of attention maintenance based on eye-tracking might be useful in the objective assessment of user experience for novel displays.

Biological motion perception is a specific type of perceptual organization, during which a clear image of a moving human body is perceptually generated in virtue of certain core light dots representing the major joint movements. While the processes of biological motion perception have been studied extensively for almost a century, there is still a debate on whether biological motion task performance can be equally precise across all visual field or is central visual field specified for biological motion perception. The current study explores the processes of biological motion perception and figure–ground segmentation in the central and peripheral visual field, expanding the understanding of perceptual organization across different eccentricities. The method involved three different tasks of visual grouping: (1) a static visual grouping task, (2) a dynamic visual grouping task, and (3) a biological motion detection task. The stimuli in (1) and (2) were generated from 12–13 dots grouped by proximity and common fate, and, in (3), light dots representing human motion. All stimuli were embedded in static or dynamics visual noise and the threshold value for the number of noise dots in which the elements could still be grouped by proximity and/or common fate was determined. The results demonstrate that biological motion can be differentiated from the scrambled set of moving dots in a more intensive visual noise than static and dynamic visual grouping tasks. Furthermore, in all three visual tasks (static and dynamic grouping, and biological motion detection) the performance was significantly worse in the periphery than in the central visual field, and object magnification could not compensate for the reduced performance in any of the three grouping tasks. The preliminary results of nine participants indicate that (a) human motion perception involves specific perceptual processes, providing the high-accuracy perception of the human body and (b) the processes of figure–ground segmentation are governed by the bottom-up processes and the best performance can be achieved only when the object is demonstrated in the central visual field.

Full accessibility to eXtended Reality Head-Mounted Displays (XR HMDs) includes a requirement for well-functioning eyes and visual system. Eye and vision problems—that affect visual skills and abilities to various degrees—are common and may prevent an individual from comfortably wearing and using XR HMDs. Yet, vision problems have gained little attention in the XR community, making it difficult to assess the degree of accessibility and how to increase inclusivity. This perspective article aims to highlight the need for understanding, assessing, and correcting common eye and vision problems to increase inclusivity—to help broaden a responsible uptake of XR HMDs. There is a need to apply an interdisciplinary, human-centered approach in research. Guidelines are given for conducting reproducible research to contribute to the development of more inclusive XR technologies, through consideration of the individual variations in human visual skills and abilities.

The progression of myopia in young adults due to inadequate accommodation is currently one of the global research challenges. Studies have demonstrated that multifocal contact lenses have a different effect on accommodative response. The aim of this study was to assess the accommodative lag using various design multifocal contact lenses at different working distances. The study was conducted on 10 emmetropic subjects aged 22â28 years. An open-field autorefractor PowerRef 3 was used to assess the response of eye accommodation to stimuli placed at a distance of 25 cm and 40 cm for subjects wearing monofocal and multifocal contact lenses. To determine the effectiveness of contact lens design for accommodative lag compensation, the results of the accommodative lag with and without contact lenses were compared. The measured accommodative lag for stimuli at 40 cm was 1.05 ± 0.11 D and for stimuli at 25 cm 1.53 ± 0.11 D. Regarding the effect of multifocal contact lenses, it was determined that the near vision power zone in the centre of the lens reduces the accommodative lag, while the respective distance vision power zone does not produce a statistically significant change. The near power zone in the centre of the multifocal contact lens effectively affects the accommodative lag by reducing accommodation inaccuracy as effectively as spherical contact lenses with positive power. The addition design for multifocal lenses (Med or Hi) does not significantly affect the accommodative lag. The results of centre-distance multifocal contact lenses depend on the strength of the addition used.

The coronavirus disease caused by the SARS-CoV-2 virus (COVID-19) pandemic has changed not only global epidemiological and economic developments but also the lives of every individual, with particular severity for patients. The number of acute illness cases grew rapidly, significantly increasing the workload of hospitals, and simultaneously, new chronic diseases emerged, such as persistent post-COVID-19 syndrome (PPCS), with unclear etiology, symptoms, and complexity—similar to myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS). Accordingly, the burden of chronic diseases poses new long-term challenges for primary healthcare and requires new approaches to patient care. This chapter provides insight into the integrative approach to healthcare and focuses on potentially new solutions by implementing an integrative attitude to the treatment of post-COVID-19 and ME/CFS patients in primary healthcare. Integrative health coaching contributes the holistic approach to patients’ overall health and resilience through cognitive practice and patient active engagement. The findings of this chapter can enrich the person-centered approach and healthcare system strengthening through holistic measures and systems thinking.

Background and Objectives: For preterm infants, breastmilk plays an important role in their development, but mothers encounter a number of barriers to breastfeeding. The aim of this study was to investigate breastfeeding prevalence in preterm infants and to examine factors that may face mothers when starting to feed at-breast and their impact on the result. Methods: Women (N = 79) with preterm infants (N = 84) were interviewed within the follow-up program in Latvia during a six-month period in 2018 using the original study protocol. Results: 61.9% infants were breastfed and 38.1% were not. The median infant birth weight in breastfed group was 1730 g, the median duration of tube feeding 21 days. The median age when started to feed at-breast 33 days. Later only 40.4% infants were still feeding at-breast. A relationship was found between breastfeeding and the mother’s confidence during pregnancy that she would breastfeed (P

Research purpose. The goal of the current paper is to investigate the impact of internal factors on bank performance. All the performance indicators and explanatory factors have been distinguished from the scientific literature. Design/methodology/approach. To investigate if there was an effect of the distinguishing factors on Latvian banks’ performance, correlation-regression analysis was applied. To test the developed models’ accuracy, determination coefficient, Durbin–Watson coefficient, variance inflation factor (VIF), Cook’s distance and p-value were computed. Findings. The findings revealed that there was a relationship between all the dependent and independent factors, except return on assets (ROA) and return on equity (ROE). ROA has a significant positive relationship only with net commission income, and ROE, with net interest margin and net commission income. Moreover, two regression models were developed and showed that total assets and number of automated teller machines (ATMs) affect the profitability, represented by earnings before interest, taxes, depreciation, and amortization (EBIDTA) and bank value. Originality/value/practical implications. The current findings contribute to the scientific literature dealing with commercial banks’ performance issue and could be used by the banks to develop strategies for maximising profitability.

Summary Introduction Aneurysmal subarachnoid haemorrhage (SAH) is associated with high mortality and morbidity. Rebleeding, cerebral vasospasm (VS) with delayed cerebral ischemia (DCI) are major complications after SAH associated with poor neurological outcome. Aim of the study To summarize the existing research data on the SAH from incidence, risk factors and clinical presentation to diagnostic, monitoring and treatment options after SAH. Materials and Methods Literature review was carried out to identify factors associated with SAH using specific keywords (aneurysmal subarachnoid haemorrhage, rebleeding, cerebral vasospasm, delayed cerebral ischemia) in the PUBMED database. In the time period from 2000 to 2019, 34 full articles were reviewed. Results According to the literature, the key risk factors for cerebral aneurysms and the SAH are hypertension, smoking, chronic alcohol abuse, family history of intracranial aneurysms in first-degree relatives and female sex. The key risk factor for early complication - rebleeding after SAH - is hypertension. The factors responsible for late complications - cerebral VS and DCI after SAH - are initially lower Glasgow coma scale and higher grades of Fisher scale, where grade IV and III predict cerebral VS in 31–37%. Furthermore, hyperglycaemic state, hyponatremia, hypotension and cerebral hypoperfusion, increased level of Troponin correlate with the incidence of cerebral VS and DCI. Although the golden standard to detect cerebral VS is digital subtraction angiography, CT angiography has become a routine examination. Transcranial doppler sonography is recommended and regional cerebral oximetry also seems to be promising. To avoid rebleeding for wide-necked, gigantic aneurysms or when SAH is combined with intraparenchymal hematoma, surgical clipping is preferred. For posterior circulation aneurisms, poor grade SAH and patients with age >70 years superior is endovascular treatment. To avoid late complications, the pharmacological method is used with Nimodipine. Conclusions SAH is still associated with poor clinical outcome due to the development of early and late complications. The highest risk patients are those with low Glasgow coma scale and high grades of Fisher scale. Timely performed obliteration methods of the ruptured aneurysm are crucial and Nimodipine is the main agent to prevent cerebral VS and DCI.

Myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) is a complex disease that is mainly diagnosed based on its clinical symptoms. Biomarkers that could facilitate the diagnosis of ME/CFS are not yet available; therefore, reliable and clinically useful disease indicators are of high importance. The aim of this work was to analyze the association between ME/CFS clinical course severity, presence of HHV-6A/B infection markers, and plasma levels of autoantibodies against adrenergic and muscarinic acetylcholine receptors. A total of 134 patients with ME/CFS and 33 healthy controls were analyzed for the presence of HHV-6A/B using PCRs, and antibodies against beta2-adrenergic receptors (β2AdR) and muscarinic acetylcholine receptors (M3 AChR and M4 AChR) using ELISAs. HHV-6A/B U3 genomic sequence in whole-blood DNA was detected in 19/31 patients with severe ME/CFS, in 18/73 moderate ME/CFS cases, and in 7/30 mild ME/CFS cases. Severity-related differences were found among those with a virus load of more than 1,000 copies/106 PBMCs. Although no disease severity-related differences in anti-β2AdR levels were observed in ME/CFS patients, the median concentration of these antibodies in plasma samples of ME/CFS patients was 1.4 ng/ml, while in healthy controls, it was 0.81 ng/ml, with a statistically significant increased level in those with ME/CFS (p = 0.0103). A significant difference of antibodies against M4 AChR median concentration was found between ME/CFS patients (8.15 ng/ml) and healthy controls (6.45 ng/ml) (p = 0.0250). The levels of anti-M4 plotted against disease severity did not show any difference; however, increased viral load correlates with the increase in anti-M4 level. ME/CFS patients with high HHV-6 load have a more severe course of the disease, thus confirming that the severity of the disease depends on the viral load—the course of the disease is more severe with a higher viral load. An increase in anti-M4 AchR and anti-β2AdR levels is detected in all ME/CFS patient groups in comparison to the control group not depending on ME/CFS clinical course severity. However, the increase in HHV-6 load correlates with the increase in anti-M4 level, and the increase in anti-M4 level, in turn, is associated with the increase in anti-β2AdR level. Elevated levels of antibodies against β2AdR and M4 receptors in ME/CFS patients support their usage as clinical biomarkers in the diagnostic algorithm of ME/CFS.

To develop a method for the preparation of MgO nanoparticles, precatalyst synthesis from magnesium nitrate with ammonia and calcination was performed in presence of PEG in air. Without PEG, the catalysts are inactive. The conversion to hydroxide was performed using a PEG/MgO molar ratio of 1, but, before the calcination, excess of PEG was either saved (PEG1) or increased to 2, 3, or 4 (PEG 2–4). Catalysts were calcined at 400–660 °C and characterized using XRD, N2 adsorption-desorption, TGA, FTIR, and SEM. The FAME yield in the reactions with methanol depend on the PEG ratio used and the calcination temperature. The optimal calcination temperature and highest FAME yield in the 6 h reactions for catalysts PEG1, PEG2, PEG3 and PEG4 were 400 °C, 74%; 500 °C, 80%; 500 °C, 51% and 550 °C, 31%, respectively. The yield dependence on calcination temperature for catalysts with a constant PEG ratio is similar to that of a bell curve, which becomes wider and flatters with an increase in PEG ratio. For most catalysts, the FAME yield increases as the size of the crystallites decreases. The dependence of FAME and the intermediate yield on oil conversion confirms that all catalysts have strong base sites.

The presented article reviews the tasks and methods of recruiting KGB agents among the clergy and laity of the Roman Catholic and Evangelical Lutheran Church in the Latvian SSR from 1944 to 1991. The primary sources of the author’s research are the documents from the archive of the KGB of the LSSR, which have become available for scientific research since December 2018 by the Law of the Republic of Latvia “On the preservation, use of documents of the former State Security Committee and establishing the fact of cooperation of persons with the KGB”. The most significant is the alphabetic file of active agents and the electronic database of operational data “Delta Latvia”. Besides, documents from archives of the Commissar of the Council for Religious Affairs and the Council on Religious Affairs under the Council of Ministers of the USSR in the LSSR, the criminal cases of some convicted priests, stored in the State Archives of Latvia and the author’s interviews with some former KGB agents are used. The review also considers examples that characterise the recruitment methods and the agency’s tasks.

The experience of information support of investment activities, including in the Russian Federation, the Kingdom of the Netherlands, the United Arab Emirates, is analyzed. The paper considers the interactive portal "Investor Roadmap" of the state institution "National Agency of Investment and Privatisation" in the context of its use as an effective tool in attracting foreign direct investment in the economy of the Republic of Belarus in the conditions of digital transformation.

Darba tēma ir “Roku higiēniskās apstrādes attīstības vēsture Latvijā no 20. gadsimta 20. gadiem māsu profesijā”. Latvijā par šo tēmu pirmais pētījums tika veikts 2017.gadā un uzrādīja, ka personālam nav pietiekošu zināšanu pareizā roku higiēniskā apstrādē. Pasaulē veiktie pētījumi arī parāda, ka roku higiēnisko apstrādi neievēro pietiekami, un ir nepieciešams māsas un citu veselības aprūpē strādājošo personālu vairāk izglītot par roku mazgāšanu un dezinfekciju. Darba mērķis ir noskaidrot roku higiēniskās apstrādes vēsturi Latvijā no 20. gadsimta 20. gadiem māsu profesijā. Pētījuma uzdevumi ir analizēt vēsturiskos materiālus, dokumentus un citu pieejamo literatūru, izstrādāt strukturētu interviju, mērķtiecīgi atlasīt respondentus, veikt respondentu intervēšanu, salīdzināt rezultātus no literatūras avotiem un iegūtos rezultātus no intervijām, apstrādāt un apkopot saņemto informāciju un izvirzīt secinājumus. Pētījuma jautājums - kā attīstījās roku higiēniskā apstrāde Latvijā no 20. gadsimta 20. gadiem māsu profesijā? Pētījumā tika izmantota kvalitatīvā metode, pētījuma instruments ir dokumentu analīzes protokols un strukturēta intervija. Pētījums tika veikts no 04.05.2022 līdz 16.05.22, pētījumā piedalījās 6 respondenti. Katrs no respondentiem atbildēja uz intervijas jautājumiem un pastāstīja par savu pieredzi roku higiēniskajā apstrādē mācību procesā un profesionālajā darbībā. Rezultāti uzrādīja, ka 20. gadsimta otrajā pusē nebija tik plaši pieejami un izmantoti dezinfekcijas līdzekļi un bija problēmas ar mācību materiāliem, salīdzinot ar 21. gadsimtu un mūsdienām., The topic of the work is "History of the development of hand hygienic treatment in Latvia from the 1920s in the nursing profession". The first study on this topic in Latvia was conducted in 2017 and showed that the staff did not have sufficient knowledge of the proper hand hygienic treatment. Global research also shows that hand hygiene is not being followed enough and that there is a need to educate nurses and other healthcare professionals more about hand washing and disinfection. The aim of the work is to find out the history of hand hygienic treatment in Latvia from the 1920s in the nursing profession. The tasks of the research are to analyze historical materials, documents and other available literature, to develop a structured interview, to select respondents, to interview respondents, to compare results from literature sources and results obtained from interviews, to process and summarize the received information and draw conclusions. Research question - how did the hygienic treatment of hands develop in Latvia from the 1920s in the nursing profession? Qualitative method is used in research, the research tool is a document analysis protocol and a structured interview. The research was carried out from 04.05.2022 to 16.05.22, in research participated 6 respondents. Each of the respondents answered the interview questions and told about their experience in hand hygiene in the learning process and professional activities. The results showed that disinfectants were less widely available and used in the 20th century and that there were problems with teaching materials compared to 21st century and today.

Background and ObjectivesGenetic testing has become an integral part of health care, allowing the confirmation of thousands of hereditary diseases, including neuromuscular disorders (NMDs). The reported average prevalence of individual inherited NMDs is 3.7–4.99 per 10,000. This number varies greatly in the selected populations after applying population-wide studies. The aim of this study was to evaluate the effect of genetic analysis as the first-tier test in patients with NMD and to calculate the disease prevalence and allelic frequencies for reoccurring genetic variants.MethodsPatients with NMD from Latvia with molecular tests confirming their diagnosis in 2008–2020 were included in this retrospective study.ResultsDiagnosis was confirmed in 153 unique cases of all persons tested. Next-generation sequencing resulted in a detection rate of 37%. Two of the most common childhood-onset NMDs in our population were spinal muscular atrophy and dystrophinopathies, with a birth prevalence of 1.01 per 10,000 newborns and 2.08 per 10,000 (male newborn population), respectively. The calculated point prevalence was 0.079 per 10,000 for facioscapulohumeral muscular dystrophy type 1, 0.078 per 10,000 for limb-girdle muscular dystrophy, 0.073 per 10,000 for nondystrophic congenital myotonia, 0.052 per 10,000 for spinobulbar muscular atrophy, and 0.047 per 10,000 for type 1 myotonic dystrophy.DiscussionDNA diagnostics is a successful approach. The carrier frequencies of the common CAPN3, FKRP, SPG11, and HINT1 gene variants as well as that of the SMN1 gene exon 7 deletion in the population of Latvia are comparable with data from Europe. The carrier frequency of the CLCN1 gene variant c.2680C>T p.(Arg894Ter) is 2.11%, and consequently, congenital myotonia is the most frequent NMD in our population.

The onset of the COVID-19 pandemic required not only the reorientation of learning to remote form but also a change in the form of state-funded school lunches. One of the forms of school catering allowance was food packs, which obligated parents to prepare a warm lunch for the pupil from products included in food packs. As the responsibility for providing a warm lunch for the pupil was transferred to the parents, it was important to understand the parents’ experience. The survey was used to gather parents’ experiences of school catering allowance received during the pandemic using survey administration software—Google forms; 5166 respondents from different regions of Latvia took part in the survey. The school catering allowance in the form of food packs (83.7%) can be considered successful as over 70% of respondents rated it as positive, giving a rating of 7 (good) or above. Parents from Vidzeme and Latgale had the most positive experience with food packs. The parents appreciated the support they received, stating that it provided a certain sense of security during the crisis. Parental dissatisfaction was related to the composition of food packs, lack of local products and unacceptable products, such as canned meat and fish.

Respiratory diseases are one of the leading causes of death in the world, which is why a lot of attention has been recently paid to studying the possible mechanisms for the development of pulmonary diseases and assessing the impact on their course. The microbiota plays an important role in these processes and influences the functionality of the human immune system. Thus, alterations in the normal microflora contribute to a reduction in immunity and a more severe course of diseases. In this review, we summarized the information about gut and lung microbiota interactions with particular attention to their influence on the course of chronic obstructive pulmonary disease (COPD).

In 2010 in Latvia, invasive pneumococcal disease (IPD) became a cause for concern and vaccination of infants with four doses of 7–valent pneumococcal conjugate vaccine (PCV7) commenced. In 2012, 10–valent pneumococcal conjugate vaccine (PCV10) (three doses at 2, 4, and 12–15 month of age) vaccination was introduced. We described incidence and serotype distribution of IPD in Latvia and investigated serotypes associated with death from IPD based on surveillance data. Adult vaccination against pneumococcal infection is not included in the national immunization program. Laboratory confirmed IPD cases are passively notified to the Center for Disease Prevention and Control of Latvia (CDPC) by laboratories and clinicians. We calculated incidence by age, sex, case fatality, and trend in serotypes by conducting a retrospective population-based cross-sectional study based on national IPD surveillance data. From 2012 to 2018 466 cases of IPD were reported. The highest notified incidence was in 2015 at 4.4/100,000, which fell to 3.9 in 2018. The highest mean annual IPD incidence was in infants (4.8) and in the elderly (6.0). PCV10 vaccine serotypes were the most prevalent in IPD cases up to 2015 with a decreasing trend from 50% (20/40) in 2012 to 19% (14/74) in 2018 (chi2 test for trend of odds = 0.000). PCV23nonPCV13 vaccine serotypes had an increasing trend and rose from 18% (7/40) to 34% (25/74) (chi2 test for trend of odds = 0.000). Non-Vaccine serotypes had an increasing trend and rose from 13% (5/40) to 27% (20/74) (chi2 test for trend of odds = 0.038). Reported total case fatality was 19% (87/466). The highest, at 36% (20/56), was reported in 2013. After adjusting for age, Streptococcus pneumoniae serotype 3 was associated with death from IPD (adjusted OR 2.3 95%CI 1.25–4.12 p 0.007). Surveillance data indicate evidence of serotype replacement with an increasing trend of serotype 19A and PPV23nonPCV13 and Non-Vaccine serotypes. Serotype 3 and age were associated with fatal IPD outcome. Further studies of S. pneumoniae carriage would be useful in providing more evidence to characterize serotypes' circulation.

Background and objectives: There is still an uncertainty regarding the clinical symptomatology and the diagnostic criteria in terms of myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS), as different diagnostic criteria exist. Our aim is to identify the core symptoms of ME/CFS in the outpatient setting in Riga, to distinguish symptoms in patients with ME/CFS and those with symptoms of fatigue, and to investigate patient thoughts on the onset, symptoms, treatment and effect of ME/CFS. Materials and methods: Total of 65 Caucasian patients from an ambulatory care setting were included in the study. Questionnaires, specialist evaluation of the patients and visual analogue scale (VAS) measurements were used to objectify the findings. Results: The study showed that ME/CFS with comorbidities is associated with a more severe disease. A negative correlation was found regarding an increase in age and number of current symptoms, as well as an increase in VAS score and the duration of fatigue and age in the ME/CFS without comorbidities group. Conclusions: Comorbidities tend to present with a more severe course of ME/CFS. Fatigue, myalgia, arthralgia and sleep disturbances tend to be more prevalent in the ME/CFS patients compared to the non-ME/CFS patients. VAS score has a tendency to decrease with age and duration of fatigue. Nonsteroidal anti-inflammatory drugs are the most commonly used pharmacological drug class that reduces ME/CFS symptoms.

New visualization approaches are being actively developed aiming to mitigate the effect of vergence-accommodation conflict in stereoscopic augmented reality; however, high interindividual variability in spatial performance makes it difficult to predict user gain. To address this issue, we investigated the effects of consistent and inconsistent binocular and focus cues on perceptual matching in the stereoscopic environment of augmented reality using a head-mounted display that was driven in multifocal and single focal plane modes. Participants matched the distance of a real object with images projected at three viewing distances, concordant with the display focal planes when driven in the multifocal mode. As a result, consistency of depth cues facilitated faster perceptual judgments on spatial relations. Moreover, the individuals with mild binocular and accommodative disorders benefited from the visualization of information on the focal planes corresponding to image planes more than individuals with normal vision, which was reflected in performance accuracy. Because symptoms and complaints may be absent when the functionality of the sensorimotor system is reduced, the results indicate the need for a detailed assessment of visual functions in research on spatial performance. This study highlights that the development of a visualization system that reduces visual stress and improves user performance should be a priority for the successful implementation of augmented reality displays.

The effect of gamma irradiation on Gd2O3 films was studied using the thermostimulated exoelectron emission (TSEE) technique. The films were deposited on a glass and Si/SiO2 substrates using an extraction-pyrolytic method. Crystalline structure, chemical composition, film thickness and surface morphology were characterized by means of X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM) and atomic force microscopy (AFM). The films were irradiated by 10 MeV gamma photons and TSEE was measured from the irradiated films. It was found that gamma irradiation decreases TSEE intensity and the area below TSEE spectral curves. A linear correlation between the relative decrease in the area and the delivered dose was observed in a dose range of 0–10 Gy. These findings suggest that gamma radiation might decrease the density of trapped electrons present in the as-grown Gd2O3 films or create competing electron traps that inhibit TSEE from the films.

Wilson’s disease (WD) is a copper metabolism disorder, caused by allelic variants in the ATP7B gene. Wilson’s disease can be diagnosed by clinical symptoms, increased copper and decreased cerulopasmin levels, which could all also be by other genetic variants beyond the ATP7B gene, e.g., disturbed ceruloplasmin biosynthesis can be caused by pathogenic allelic variants of the CP gene. Copper metabolism in the organism is affected by several molecules, but pathogenic variants and related phenotypes are described with COMMD1 and ATOX1 genes. The aim of the study was to test other genes, CP, ATOX1 and COMMD1, for possible influence to the manifestation of WD. Patients were enrolled on the basis of Leipzig’s diagnostic criteria, 64 unrelated patients with confirmed WD. Direct sequencing of promoter region of the CP gene and ATOX1 and COMMD1 gene exons was conducted. Statistically significant differences were found between the two variants in the CP gene and the ATP7B genotype (rs66508328 variant AA genotype and the rs11708215 variant GG genotype) were more common in WD patients with an unconfirmed ATP7B genotype. One allelic (intronic) variant was found in the ATOX1 gene without causing the functional changes of the gene. Three allelic variants were identified in the COMMD1 gene. No statistically significant differences were found between allele and genotype frequencies and the first clinical manifestations of WD. Different variants of the CP gene contributed to a WD-like phenotype in clinically confirmed WD patients with neurological symptoms and without identified pathogenic variants in the ATP7B gene. Allelic variants in the ATOX1 and COMMD1 genes do not modify the clinical manifestation of WD in Latvian patients. (266 words)

Microwave-assisted hydrothermal synthesis of TiO2 nanofibers under various temperature and pressure conditions were done in this research. High quality TiO2 nanofiber coatings where obtained when temperature was in range 240 – 245 °C and pressure was 27.3 – 29.1 bar. Obtained TiO2 nanofiber coatings are with a specific surface area of ​​151.5 to 158.9 m2· g-1 before calcination. Comparing with nanopowder photocatalysts nanofiber coatings photocatalysts can be much easier removed from solution after the photocatalysis process. Such coatings with relative large specific surface area are with higher potential application in industry.

Data on migration flows suggest that young people are highly mobile. Yet, there are gaps in the evidence concerning the factors driving young people’s international migration in Latvia. Latvia is a potentially interesting case because of the high rate of migration from the country, but also because it is a complex ethnic and linguistic environment. Latvian and Russian speaking populations are shown to have diverse migration drivers, and this study addresses the differences in attitudes to studying and living abroad for adolescents at the time of school graduation. Literature suggests that Russian-speaking population have higher propensity to emigrate. We aim to contribute to the literature by exploring differences in migration intentions between Latvian and Russian speaking high school graduates.This study is based on individual-level survey data of secondary school graduates in Latvia in 2020, amidst COVID-19 pandemic. We analyse the strength of migration intentions from definitely not leaving Latvia to surely planning to emigrate. We conclude that Russian-speakers exhibit stronger intentions to emigrate compared Latvian-speaking youngsters, driven by wider networks and expected higher returns to their human capital abroad.

Many shared views of both scholars and practitioners reflect spatial planning as a place-creating process that must be understood from a multi-level perspective. Formal and informal planning modes have variations in planning practices in different countries. In this study, we aimed to evaluate the interaction of formal and informal spatial planning in the frame of the spatial planning system in the Baltic Sea region. We were searching to highlight the involvement possibilities of territorial communities in the spatial planning process around the Baltic Sea region, focusing on coastal areas and their specific features in Latvia, Estonia, the Åland Islands of Finland, and Sweden. Involved experts expressed views based on a pre-developed model to identify how institutionalized formal spatial planning relates with informal interventions. This allowed the development and proposal of a model for coastal area spatial planning and implementation. We concluded that in the spatial planning approach, the governance works differently in different countries, and coastal area spatial planning differs from regular spatial planning. The information base is sufficient to initiate spatial planning at the municipal level, but municipalities should be more active, involving territorial communities in the planning, implementation, and control of municipal spatial planning, as this ensures a greater interest in the use of planning outcome.

The main objective of this study was to investigate the association between final-year students’ anxiety level and quality of life (QOL) with their academic achievements. A longitudinal study was performed in regular schools and in high-rated gymnasiums at the beginning and at the end of the school year. Multiple linear regression models were built for the association between level of anxiety/QOL with academic achievements. Type of school and gender—but not the level of anxiety—were the main predictors of academic achievements of 287 adolescents (e.g., for mathematics, the effect estimates were: β = −1.71 [95% confidence interval −2.21, −1.21], β = −0.50 [−0.95, −0.06], β = 0.09 [−0.02, 0.20] for the type of school, gender, and changes in level of anxiety, respectively). To conclude, particular efforts should be made to reduce the level of anxiety in girls, especially those that study in high-rated schools.

The aim of this study was to analyse the volumetric and crossectional parameters of masseter and medial pterygoid muscles in the relation with mandibular skeletal morphology in individuals with different underlying growth patterns in the vertical dimension.The study originally involved 76 individuals with definite clinical and radiological criteria: 31 skeletal Class III and 26 skeletal Class II patients before the orthognathic surgery and 20 skeletal class I (normal) individuals with complaints of wisdom teeth and associated medical problems. On the basis of cephalometric measurement of the mandibular plane and sella-nasion (MP-SN), the study sample was categorised according to the vertical facial dimension in 3 different growth pattern subgroups: 19 subjects with horizontal growth pattern, 25 subjects with vertical growth pattern and 33 subjects with neutral growth pattern. MRI was performed for the masseter and medial pterygoid muscles, and volume and cross-sectional area measurements were performed. Cone beam computed tomography (CBCT) investigation was performed for the assessment of craniofacial structures and the following measurements of the mandibular parameters were obtained: height of ramus, length of mandibular corpus, overall mandibular length, inter-angular width and intercondylar width.There were statistically significant differences among all study groups regarding masseter volume (p0.006) and CSA (p0.006), with the highest values in the horizontal growth pattern group and the lowest values in vertical growth pattern group. After Bonferroni correction, statistically significant difference (p0.004 and p0.008) was noted between the horizontal and vertical growth pattern groups, respectively. A similar tendency was observed for the medial pterygoid, but with no statistical significance. A statistically significant negative correlation was observed between MP-SN and the volume of masseter and medial pterygoid in the overall sample. Of the seven muscular and mandibular variables included in the regression analysis, the final model included only four variables that were significantly associated with MP-SN and explained 37% of its variance (masseter volume (p=0.017), mandibular overall length (p0.001), height of mandibular ramus (p=0.003), and length of mandibular corpus (p0.001)).The masseter muscle seems to be more sensitive to the variation in mandibular morphology than the medial pterygoid muscle, and volume as the biomechanical characteristic seems to be a more significant parameter of the size of the interaction with vertical skeletal growth patterns.

By highlighting the essential features of dark tourism and its development trends, the author focuses on Holocaust memorial sites in Latvia as possible destinations for dark tourism routes. The article points to the ambiguous and often contrastive attitude of the local community towards the use of these places for dark tourism purposes, which is related to the way how and whether local communities and different social groups preserve Holocaust events in their living memories. According to the author, Holocaust memorial sites can be described as the sites of selected silence, and this designation quite accurately describes how society in Latvia remembers and preserves memories of its tragic historical heritage.

Pure phase and mixed phase TiO$_2$ nanoparticles have been produced using a pyrolytic method from a non-aqueous carboxylate precursor. The precursor was prepared by a multiphase cation exchange using pentanoic acid (C$_4$H$_9$COOH). The thermal stability, polymorph content, morphology, size distribution and surface region of the produced nanoparticles were studied by TGA/DSC, XRD, FTIR and TEM. High quality monodisperse nanoparticles have been produced in the size range from 7 to 27 nm. The nanoparticles showed room temperature ferromagnetism revealed by VSM within bound polaron model. The carboxylate precursor is a good alternative to standard sol-gel to produce nanoparticles free from impurities.

Iron deficiency is one of the leading risk factors for disability and death worldwide. Targeted iron supplementation with pharmaceuticals is widely used, but oral iron salt ingestion often causes side effects—nausea, vomiting, abdominal pain. The present study demonstrated that red beetroot juice (RBRJ) contains a compound or compound complex with the ability to specifically stimulate duodenal iron absorption, shown in experiments in vitro, in situ and in vivo. The effect does not depend on juice sugar and ascorbic acid concentration. Fractionated RBRJ impact on iron absorption is dose dependent. This phenomenon is described for the first time.

Background Wilson disease (WD) is an autosomal recessive disorder of copper metabolism caused by allelic variants in ATP7B gene. More than 500 distinct variants have been reported, the most common WD causing allelic variant in the patients from Central, Eastern, and Northern Europe is H1069Q. Methods All Latvian patients with clinically confirmed WD were screened for the most common mutation p.H1069Q by PCR Bi-PASA method. Direct DNA sequencing of gene ATP7B (all 21 exons) was performed for the patients with WD symptoms, being either heterozygous for H1069Q or without it on any allele. Results We identified 15 different allelic variants along with eight non-disease-causing allelic variants. Based on the gene molecular analysis and patients' clinical data variant p.His1069Gln was found in 66.9% of WD alleles. Wide clinical variability was observed among individuals with the same ATP7B genotype. The results of our study confirm that neurological manifestations of WD are typically present later than the liver disease but no significant association between the presence/absence of the most common genetic variant and mode of initial WD presentation or age at presentation was identified. Conclusions (1) The most prevalent mutation in Latvian patients with Wilson disease was c.3207C>A (p.His1069Gln); (2) No significant phenotype–genotype correlation was found in Latvian patients with Wilson disease; (3) The estimated prevalence of Wilson disease in Latvia is 1 of 24,000 cases which is higher than frequently quoted prevalence of 1: 30,000.

Before World War II Latvia had several strong traditional religious communities: Lutheran, Roman Catholic, Baptist, Russian Old Believers and Orthodox. After the war, the Soviet regime extended the persecution of these communities eliminating the most disobedient clergymen and church members. The property of religious groups was nationalized, and many parishes were abolished. Even after the repressions, religious communities continued to be active. However, to preserve their faith, they had to seek compromises with the Soviet regime, including with the KGB. The chapter focuses on the two main Christian churches in Latvia, the Roman Catholic Church and the Evangelical Lutheran Church, explaining a nuanced history of their collaboration with the Soviets and the current view of the leaders of both churches on this dark past.

Encefalomielitis miàlgica/síndrome de fatiga crònica; Cura; Diagnòstic Myalgic encephalomyelitis/chronic fatigue syndrome; Care; Diagnosis Encefalomielitis miálgica/síndrome de fatiga crónica; Cuidado; Diagnóstico Designed by a group of ME/CFS researchers and health professionals, the European Network on Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (EUROMENE) has received funding from the European Cooperation in Science and Technology (COST)—COST action 15111—from 2016 to 2020. The main goal of the Cost Action was to assess the existing knowledge and experience on health care delivery for people with Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS) in European countries, and to enhance coordinated research and health care provision in this field. We report our findings and make recommendations for clinical diagnosis, health services and care for people with ME/CFS in Europe, as prepared by the group of clinicians and researchers from 22 countries and 55 European health professionals and researchers, who have been informed by people with ME/CFS. This research received no external funding. EUROMENE receives funding for networking activities from the COST programme (COST Action 15111), via the COST Association.

Contains fulltext : 240193.pdf (Publisher’s version ) (Open Access) Many children have undetected vision problems or insufficient visual information processing that may be a factor in lower academic outcomes. The aim of this paper is to contribute to a better understanding of the importance of vision screening for school-aged children, and to investigate the possibilities of how eye-tracking (ET) technologies can support this. While there are indications that these technologies can support vision screening, a broad understanding of how to apply them and by whom, and if it is possible to utilize them at schools, is lacking. We review interdisciplinary research on performing vision investigations, and discuss current challenges for technology support. The focus is on exploring the possibilities of ET technologies to better support screening and handling of vision disorders, especially by non-vision experts. The data orginate from a literature survey of peer-reviewed journals and conference articles complemented by secondary sources, following a rapid review methodology. We highlight current trends in supportive technologies for vision screening, and identify the involved stakeholders and the research studies that discuss how to develop more supportive ET technologies for vision screening and training by non-experts 23 p.

Introduction Vision problems affect academic performance, social and mental health. Most traditional vision screening methods rely on human expert assessments based on a set of vision tests. As technology advances, new instruments and computerised tools are available for complementing vision screening. The scoping review based on this protocol aims to investigate current technologies for vision screening, what vision tests can be complemented by technologies, and how these can support vision screening by providing measurements. Methods and analysis The planned review will utilise the PRISMA extension for Scoping Reviews (PRISMA-ScR) tool. Electronic search will be performed in databases, including Web of Science, MEDLINE (Ovid), Scopus, Engineering Village, Cochrane and Embase. We will perform a systematic search in selected reference databases without the limitation on publications dates, or country of studies. Reference management software, like EndNote and DistillerSR, will be used to remove duplicate entries. Two authors will independently analyse the studies for inclusion eligibility. Conflicts will be resolved by discussion. We will extract the types of technologies, types of vision tests they complement and the measurements for the included studies. Overall findings will be synthesised by thematic analysis and mapping to the logic model. Ethics and dissemination Ethical approval is not required for this review, as it will only summarise existing published data. We will publish the findings in an open access, peer-reviewed journal. We expect that the review results will be useful for vision screening experts, developers, researchers, and policymakers.

Designed by a group of ME/CFS researchers and health professionals, the European Network on Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (EUROMENE) has received funding from the European Cooperation is Science and Technology (COST) (https://www.cost.eu/cost-actions/what-are-cost-actions/ ) - COST action 15111 - from 2016 to 2020. The main goal of the Cost Action was to assess the existing fragmented knowledge and experience on health care delivery for people with Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS) in European countries, and to enhance coordinated research and health care provision in this field. We report on the recommendations for clinical diagnosis, heath services and care for people with ME/CFS in Europe, as prepared by the group of clinicians and researchers from 22 countries and 55 European health professionals and researchers, who have been informed by people with ME/CFS (https://www.cost.eu/actions/CA15111/#tabs|Name:overview).

Topics concerning food and diets have gained prominence in academic writing, policy debates and media coverage, not least due to public health problems, sedentary lifestyles, and concerns regarding dietary habits and the impact of food production on climate change. The purpose of this paper is to reveal the ways dietary practices have been framed in the media through an analysis of Latvian print and digital media articles. A selection of 192 media articles published between 2014 and 2019 were analysed through the perspective of framing. The analysis identifies three prominent frames found in Latvian media: (i) a biomedical frame, (ii) a psychological frame, and (iii) a social practice frame. The frames are connected by several cross-cutting themes: individualisation, self-disciplining, gendering, and medicalisation. The results suggest that the media portray unhealthy dietary as the responsibility of individuals, whilst ignoring, with some exceptions, the impact of broader societal and food system processes. These results call for more attention to be paid by media content creators to the diversity of actors involved in food production, consumption and distribution and their inter-connections, as well as the impact that food systems have on economic, social, and ecological sustainability.

Background: We compared the efficiency of two MRI diffusion weighted imaging (DWI) techniques: DWI with SPIR (DWISPIR) and DWI with STIR (DWISTIR), to estimate their eligibility for quantitative assessment of Crohn’s disease activity in children and adults. Methods: In inflamed terminal ileum segments (n = 32 in adults, n = 46 in children), Magnetic Resonance Index of Activity (MaRIA) was calculated, ADC values of both DWI techniques were measured, and the corresponding Clermont scores calculated. ADC values of both DWI techniques were compared between both and within each patient group, assessing their mutual correlation. Correlations between MaRIA and the corresponding ADC values, and Clermont scores based on both DWI techniques were estimated. Results: No correlation between ADC of DWISPIR and DWISTIR was observed (rho = 0.27, p = 0.13 in adults, rho = 0.20, p = 0.17 in children). The correlation between MaRIA and Clermont scores was strong in both techniques—in SPIR, rho = 0.93; p < 0.0005 in adults, rho = 0.98, p < 0.0005 in children, and, in STIR, rho = 0.89; p < 0.0005 in adults, rho = 0.95, p < 0.0005 in children. The correlation between ADC and MaRIA was moderate negative for DWISTIR (rho = 0.93, p < 0.0005 in adults, rho = 0.95, p < 0.0005 in children), but, in DWISTIR, no correlation between ADC and MaRIA score was observed in adults (rho = −0.001, p = 0.99), whereas children presented low negative correlation (rho = −0.374, p = 0.01). Conclusions: DWISTIR is not suitable for quantitative assessment of Crohn’s disease activity both in children and adult patients.

In Latvia, the learners of secondary school as a requirement gets acquainted with basics of research – selection of literature, data collection and processing, communication and presentation skills.The present article deals with an analysis of the themes and texts (corpus) of the research papers (RP) in Health Science worked out by the authors of the top-ranked RP presented in the Scientific Conference of High School Learners of Latvia from 2016 to 2019. A logical inductive content analysis of features specific to each RP, and sequential categorization and grouping into a higher level of components were performed. The quantitative data were processed by using AntConc, IBM SPSS Statistics 22 and Microsoft Excel software.The aim of the research was to find out the themes and content variations of RP, and the characteristics of the language – tokens, types and keywords.The results show that there is a thematic uniformity in RP. The statistical characteristics of language differ in terms of lexical diversity and the frequency of keywords and their collocations. Mostly individual keywords dominate.The results obtained can be used to develop recommendations for learners and teachers as a model for theme selection, presentation of research and criteria for evaluating RP.

Human herpes virus-6 (HHV-6) and human herpes virus-7 (HHV-7) are immunomodulating viruses potentially affecting the nervous system. We evaluated the influence of HHV-6 and HHV-7 infections on fibromyalgia (FM) clinical course. Forty-three FM patients and 50 control group participants were enrolled. 39.50% (n = 17) FM patients had light A delta and C nerve fiber damage, 27.91% (n = 12) had severe A delta and C nerve fiber damage. 67.44% (n = 29) FM patients had loss of warm sensation in feet, loss of heat pain sensation, and increased cold pain sensation (34.90%,n = 15 in both findings). HHV-6 and HHV-7 genomic sequences in peripheral blood DNA in 23/43 (51.00%) and 34/43 (75.50%) of samples from FM patients and in 3/50 (6.00%) and 26/50 (52.00%) of samples from the control group individuals were detected. Active HHV-6 (plasma viremia) or HHV-7 infection was revealed only in FM patients (4/23, 17.40% and 4/34, 11.80%, respectively). A statistically significant moderate positive correlation was found between A delta and C nerve fiber damage severity and HHV-6 infection (p r = 0.410). 23/43 patients from the FM group and control group participants HHV-6 and 34/45 HHV-7 did have infection markers. A statistically significant moderate positive correlation was found between A delta and C nerve fiber damage severity and HHV-6 infection (p r = 0.410). No difference was found between detection frequency of persistent HHV-6 and HHV-7 infection between FM patients and the control group. Statistically significant correlation was observed between quantitation of changes in QST thermal modalities and HHV-6 infection. There was no correlation between A delta and C nerve fiber damage and HHV-7 infection.

Despite the market saturation with a wide range of calcium preparations in dietary supplements as well as in pharmaceuticals, calcium product safety and efficacy remain an item for further optimization. Bones and teeth mainly consist of calcium phosphate, but tablets and capsules are predominantly produced from calcium carbonate. On the other hand, in human food Ca2+ is bound with a lot of anions—carbonates, sulphates, chlorides, phosphates, citrates, oxalates etc. It seems that traditional calcium formulations due its low bioavailability cannot provide all spectra of biological calcium-dependant effects and dietary calcium might be safer and more effective than traditional calcium supplements and medicines. To increase calcium salt efficacy a new formulation of calcium salts has been developed. It is a mixture (water suspension) of amorphous calcium carbonate, citrate, hydrocarbonate, as well as magnesium hydrocarbonate and hydrocitrate as stabilizers. The capacity of a cockerel’s duodenal mucosa to absorb Ca2+ after peroral ingestion of the mentioned composition in vivo was as much as 126% higher in comparison with CaCO3 suspension intake. Vitamin D3 enhanced the amorphous antirachitic activity of calcium salts. The aim of the study was to compare original amorphous calcium salt composition bioavailability with Ca salts most often in food and medicines, as well as to evaluate the antirachitic activity of the mentioned composition in combination with vitamin D3 in chickens.

The change of corneal shape in keratoconus subjects can impact the optical quality of the eye on the retina and it reduces the contrast sensitivity by light scattering. The aim of our study was to estimate the keratoconus subjects’ contrast sensitivity and visual acuity depending on keratoconus apex position. We included 45 keratoconus subjects (77 eyes), which have keratoconus in the first to the third stage, in our study. There were 33 eyes with keratoconus apex in the central part of the cornea and 46 eyes with keratoconus apex in the periphery of the cornea. Contrast sensitivity and visual acuity were measured at 3 m with and without the best possible spectacle correction using the FrACT program 3.9.3. The contrast sensitivity was measured at following frequencies – 1, 3, 5, 7, 9, 11, 13, and 15 cpd. The results showed that keratoconus subjects have lower contrast sensitivity in all spatial frequencies than subjects without pathological changes. The lowest contrast sensitivity was in keratoconus subjects with a central apex position compared to contrast sensitivity with peripheral apex position. The difference of contrast sensitivity between subjects with and without pathology increased up to 11 cpd but remained rather constant at the highest spatial frequencies – 11, 13, and 15 cpd. There was statistically significant difference between the median of visual acuity in subjects with central apex (0.42 decimal system) and subjects with peripheral apex (0.60 decimal system).