608 research outputs found

    Subjective method of refractometry and depth of focus

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    AbstractPurposeTo study the impact of the depth of focus on subjective refraction and distribution of myopic and hyperopic refractions.MethodsA total of 450 eyes of 305 subjects in the age range of 23–34 years were recruited for the study. A distribution of refractions was examined using a traditional method of the subjective refractometry on the basis of point-like posterior focus notion. Correction of the results was made on the assumption that the emmetropic eye retains high visual acuity when applying convex lenses with values which are fewer or equal to the depth of focus values. The following values of the depth of focus were used: ±0.55D, ±0.35D and ±0.2D for visual acuity 1.0, 1.5 and 2.0, respectively.ResultsApplication of the traditional method of refractometry produced the following occurrence of refractions: hypermetropia 59.3%, myopia 22% and emmetropia 18.7%. After correction of the initial results of values of the depth of focus the distribution of refractions was as follows: hypermetropia 12.7%, myopia 22% and emmetropia 65.3%.ConclusionThe traditional method of subjective refractometry with application of trial lenses was developed on the basis of data of large optical aberrations and significant depth of focus which values should be taken into account during interpretation of results of subjective refractometry. Our data regarding to prevalence of emmetropic refraction falls in line with basic science provisions in respect of the physiology of the eye

    Digital Media Image of Business University Professor

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    Digitalization of business and society inevitably affects almost all spheres, and education is not an exception. New high-tech tools and solutions are rapidly coming into this industry, without which further development and implementation of the educational process is no longer possible. Today target audience of any educational organizations is informationally advanced and prefers to source useful information from social networks, often making business decisions based on it. Such conditions put forward new requirements for educational organizations to increase their activity in social networks and, above all, to form a digital image. Professors are the face of any educational organization. Inasmuch as they are the subjects who directly interact with students, their personal digital image plays an important role in shaping corporate image of the university. Relevance of this article is in the research of the digital image process formation by professors of business universities, which are the flagships and market-oriented subjects of local higher education.The article aims to identify the current state of forming the digital image of teachers of entrepreneurial universities in social networks. To achieve the goal, the article discusses the features of an entrepreneurial university and the characteristics of its corporate image, shows the need to form a teacher’s digital image and identifies strategies for such formation in social networks. The study of the activity of Russian entrepreneurial universities’ teachers in social networks was carried out and the comparison of the results with the similar activity of foreign universities’ teachers was made

    Magnetospheric convection from Cluster EDI measurements compared with the ground-based ionospheric convection model IZMEM

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    Cluster/EDI electron drift observations above the Northern and Southern polar cap areas for more than seven and a half years (2001–2008) have been used to derive a statistical model of the high-latitude electric potential distribution for summer conditions. Based on potential pattern for different orientations of the interplanetary magnetic field (IMF) in the GSM y-z-plane, basic convection pattern (BCP) were derived, that represent the main characteristics of the electric potential distribution in dependence on the IMF. The BCPs comprise the IMF-independent potential distribution as well as patterns, which describe the dependence on positive and negative IMF<I>B<sub>z</sub></I> and IMF<I>B<sub>y</sub></I> variations. The full set of BCPs allows to describe the spatial and temporal variation of the high-latitude electric potential (ionospheric convection) for any solar wind IMF condition near the Earth's magnetopause within reasonable ranges. The comparison of the Cluster/EDI model with the IZMEM ionospheric convection model, which was derived from ground-based magnetometer observations, shows a good agreement of the basic patterns and its variation with the IMF. According to the statistical models, there is a two-cell antisunward convection within the polar cap for northward IMF<I>B<sub>z</sub></I>+≤2 nT, while for increasing northward IMF<I>B<sub>z</sub></I>+ there appears a region of sunward convection within the high-latitude daytime sector, which assumes the form of two additional cells with sunward convection between them for IMF<I>B<sub>z</sub></I>+≈4–5 nT. This results in a four-cell convection pattern of the high-latitude convection. In dependence of the ±IMF<I>B<sub>y</sub></I> contribution during sufficiently strong northward IMF<I>B<sub>z</sub></I> conditions, a transformation to three-cell convection patterns takes place

    Gel-Based Proteomics of Clinical Samples Identifies Potential Serological Biomarkers for Early Detection of Colorectal Cancer

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    The burden of colorectal cancer (CRC) is considerable—approximately 1.8 million people are diagnosed each year with CRC and of these about half will succumb to the disease. In the case of CRC, there is strong evidence that an early diagnosis leads to a better prognosis, with metastatic CRC having a 5-year survival that is only slightly greater than 10% compared with up to 90% for stage I CRC. Clearly, biomarkers for the early detection of CRC would have a major clinical impact. We implemented a coherent gel-based proteomics biomarker discovery platform for the identification of clinically useful biomarkers for the early detection of CRC. Potential protein biomarkers were identified by a 2D gel-based analysis of a cohort composed of 128 CRC and site-matched normal tissue biopsies. Potential biomarkers were prioritized and assays to quantitatively measure plasma expression of the candidate biomarkers were developed. Those biomarkers that fulfilled the preset criteria for technical validity were validated in a case-control set of plasma samples, including 70 patients with CRC, adenomas, or non-cancer diseases and healthy individuals in each group. We identified 63 consistently upregulated polypeptides (factor of four-fold or more) in our proteomics analysis. We selected 10 out of these 63 upregulated polypeptides, and established assays to measure the concentration of each one of the ten biomarkers in plasma samples. Biomarker levels were analyzed in plasma samples from healthy individuals, individuals with adenomas, CRC patients, and patients with non-cancer diseases and we identified one protein, tropomyosin 3 (Tpm3) that could discriminate CRC at a significant level (p = 0.0146). Our results suggest that at least one of the identified proteins, Tpm3, could be used as a biomarker in the early detection of CRC, and further studies should provide unequivocal evidence for the real-life clinical validity and usefulness of Tpm3

    Characteristics of the electrojet during intense magnetic disturbances

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    Hall current variations in different time sectors during six magnetic storms from the summer seasons in 2003 and 2005 (Ritter, 2018) are examined, namely three storms in the day–night meridional sector and three storms in the dawn–dusk sector. The sequence of the phenomena, their structure and positions, and the strength of the polar (PE) and the auroral (AE) Hall electrojets were investigated using scalar magnetic field measurements obtained from the CHAllenging Minisatellite Payload (CHAMP) satellite in accordance with the study of Ritter et al. (2004a). We analyzed the correlations of the PE and AE as well as the obtained regression relations of the magnetic latitude MLat and the electrojet current intensity I with auroral and ring current activity, the interplanetary magnetic field, and the Newell et al. (2007) coupling function for the state of the solar wind. The following typical characteristics of the electrojets were revealed:The PE appears in the daytime sector at MLat&thinsp; ∼ 80°–73°, with a westward or an eastward direction depending on the interplanetary magnetic field (IMF) By component (By&thinsp; &lt; &thinsp;0&thinsp;nT or By&thinsp; &gt; &thinsp;0&thinsp;nT). Changes in the current flow direction in the PE can occur repeatedly during the storm, but only due to changes in the IMF By orientation. The PE increases with the intensity of the IMF By component from I ∼ 0.4&thinsp;A&thinsp;m−1 for By ∼ 0&thinsp;nT up to I ∼ 1.0&thinsp;A&thinsp;m−1 for By ∼ 23&thinsp;nT. The MLat position of the PE does not depend on the direction and intensity of the By component.There is no connection between MLat and I in the PE and the symmetric part of the magnetospheric ring current (index SymH). There is a correlation between I in the PE and the AsyH index, but only a very weak interconnection of this index with the MLat of the PE.Substorms occurring before the storm's main phase are accompanied by the appearance of an eastward electrojet (EE) at MLat&thinsp; ∼ 64° as well as that of a westward electrojet (WE). In the nighttime sector, a WE appears at MLat&thinsp; ∼ 64°. During the main phase both electrojets persist. The daytime EE and the nighttime WE shift toward sub-auroral latitudes of MLat&thinsp; ∼ 56° and grow in intensity up to I ∼ 1.5&thinsp;A&thinsp;m−1. The WE is then located about 6° closer to the pole than the EE during evening hours and about 2°–3° closer during daytime hours.</p

    The molecular basis of protein toxin HicA-dependent binding of the protein antitoxin HicB to DNA

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    This is the final version. Available from the publisher via the DOI in this record.Experimental SAXS data and derived models of both HicB4 and HicAB4 have been deposited in the Small Angle Scattering Biological Data Bank (SASBDB) under the accession codes SASDD45 and SASDD55.Toxin-antitoxin (TA) systems are present in many bacteria and play important roles in bacterial growth, physiology, and pathogenicity. Those that are best studied are the type II TA systems, in which both toxins and antitoxins are proteins. The HicAB system is one of the prototypic TA systems, found in many bacterial species. Complex interactions between the protein toxin (HicA), the protein antitoxin (HicB), and the DNA upstream of the encoding genes regulate the activity of this system, but few structural details are available about how HicA destabilizes the HicB-DNA complex. Here, we determined the X-ray structures of HicB and the HicAB complex to 1.8 and 2.5 Å resolution respectively and characterized their DNA interactions. This revealed that HicB forms a tetramer and HicA and HicB form a hetero-octameric complex that involves structural reorganization of the C-terminal (DNA-binding) region of HicB. Our observations indicated that HicA has a profound impact on binding of HicB to DNA sequences upstream of hicAB in a stoichiometric-dependent way. At low ratios of HicA:HicB, there was no effect on DNA binding, but at higher ratios, the affinity for DNA declined cooperatively, driving dissociation of the HicA:HicB:DNA complex.These results reveal the structural mechanisms by which HicA de-represses the HicB-DNA complex.Biotechnology and Biological Sciences Research Council (BBSRC

    СТАН БІОЦЕНОЗУ ПІХВИ ВАГІТНИХ З АНТЕНАТАЛЬНОЮ ЗАГИБЕЛЛЮ ПЛОДА

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    The aim of study – to learn the microbial biocenosis of the vagina with antenatal loss of the fetus.Materials and Methods. We examined 55 women, 30 of whom with antenatal death of fetus (АDF, principle group) and 25 women with live childbirth (control group), comparable in age, parity, somatic pathology with the main group. The study of infectious status included: microscopic examination of vaginal smears; bacteriological culture on the flora of the contents of the cervical canal; PCR diagnostics of the contents of the cervical canal, bacteriological culture of urine.Results and Discussion. The analysis showed that among women with AFD the incidence rate (number of diseases per person) was 0.77 or 76.7 ± 4.3 %, this is 2.4 times more than in the pregnant control group (morbidity rate 0.32 or 32 ± 3.1 %, p &lt;0.05). A frequent complication of the first half of pregnancy was early gestosis, menacing abortion, anemia (p &lt;0.05). The level of infection in the main group was 2.6 times higher than in the control group (p &lt;0.05). All women with vaginal infection were treated. It should be noted that during pregnancy, infection is often characterized by an asymptomatic course and frequent relapses, which may be due to changes in the hormonal balance, the presence of an immunosuppression factor associated with globulins in the serum.Concluions. In pregnant women with AFD, the peincipal risk factors for intrauterine infection of the fetus are urogenital infections of mother, chronic foci of infection in the woman's body, their aggravation during pregnancy, infectious diseases during gestation. It is necessary to make attention to the presence of a burdened obstetric-gynecological history. Activation of opportunistic flora and prolonged exposure to an infectious agent contribute to the development of immune disorders, which in turn exacerbate the dysbiotic state, thereby supporting the inflammatory process and significantly increasing the risk of intrauterine infection of the fetus until its antenatal death.Цель исследования – изучение микробного биоценоза влагалища беременных при антенатальной гибели плода.Материалы и методы. Обследовано 55 женщин, из них 30 женщин с антенатальной гибелью плода (АГП, основная группа) и 25 женщин с рождением живых детей (контрольная группа), сопоставимых по возрасту, паритету, соматической патологии. Исследование инфекционного статуса включало: микроскопическое исследование влагалищных мазков; бактериологический посев на флору содержимого цервикального канала; ПЦР-диагностику содержимого цервикального канала.Результаты исследования и их обсуждение. Проведенный анализ показал, что среди женщин с АГП коэффициент заболеваемости (число заболеваний на одного человека) составил 0,77 или (76,7±4,3) %, это в 2,4 раза выше, чем у беременных контрольной группы (коэффициент заболеваемости 0,32 или (32±3,1) %, р&lt;0,05). Достоверно чаще у пациенток основной группы беременность сопровождалась ранними и поздними гестозами, угрожающим абортом, анемией (р&lt;0,05). Уровень инфицирования при взятии на учет в основной группе был в 2,6 раза выше, чем в контрольной (р&lt;0,05). Всем женщинам с инфицированием влагалища была проведена санация. При поступлении в стационар при сравнении микробиоценоза цервикального канала у женщин с АГП и нормальным течением беременности выявлены значительные различияв количественном и качественном составе микрофлоры.Выводы. У беременных с АГП основными факторами риска внутриутробного инфицирования плода являются урогенитальные инфекции у матери, хронические очаги инфекции в организме женщины, их обострение во время беременности, инфекционные заболевания в период гестации, наличие отягощенного акушерско-гинекологического анамнеза. Активация условно-патогенной флоры и длительное воздействие инфекционного агента способствуют развитию иммунных нарушений, которые, в свою очередь, еще больше усугубляют дисбиотическое состояние, поддерживая тем самым воспалительныйпроцесс и значительно повышая риск внутриутробного инфицирования плода, вплоть до его антенатальной гибели.Мета дослідження. Метою нашого дослідження було вивчення мікробного біоценозу піхви вагітних з антенатальною загибеллМатеріал і методи дослідження. Обстежено 55 жінок, з них 30 жінок з антенатальною загибеллю плода (АЗП, основна група) та 25 жінок з народженням живих дітей (контрольна група), порівняних за віком, паритетом, соматичною патологією. Дослідження інфекційного статусу включало: мікроскопічне дослідження вагінальних мазків; бактеріологічний посів на флору вмісту цервікального каналу; ПЛР-діагностику вмісту цервікального каналу. Результати дослідження та їх обговорення. Проведений аналіз показав, що серед жінок з АЗП коефіцієнт захворюваності (число захворювань на одну людину) становив 0,77 або 76,7 ± 4,3%, це в 2,4 рази більше, ніж у вагітних контрольної групи (коефіцієнт захворюваності 0, 32 або 32 ± 3,1%, р &lt;0,05). Достовірно частіше у пацієнток основної групи вагітність супроводжувалася ранніми та пізніми гестозами, загрозливим абортом, анемією (р &lt;0,05). Рівень інфікування піхви при взятті на облік в основній групі був у2,6 рази вищим, ніж у контрольній (р &lt;0,05). Всім жінкам з інфікуванням піхви була проведена санація. При надходженні в стаціонар при порівнянні мікробіоценозу цервікального каналу у жінок з АЗП і нормальним перебігом вагітності виявлені значні відмінності в кількісному і якісному складі мікрофлори.Висновки. У вагітних з АЗП основними факторами ризику внутрішньоутробного інфікування плода є урогенітальні інфекції у матері, хронічні вогнища інфекції в організмі жінки, їх загострення під час вагітності, інфекційні захворювання в період гестації, наявність обтяженого акушерсько-гінекологічного анамнезу. Активація умовно-патогенної флори і тривалий вплив інфекційного агента сприяють розвитку імунних порушень, які, в свою чергу, ще більше посилюють дисбіотичний стан, підтримуючи тим самим запальний процес і значно підвищуючи ризик внутрішньоутробного інфікування плода аж до його антенатальної загибелі
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