Mathematical Model for the Formation of University Contingents on the Basis of Population Dynamics Equations

The mathematical model of two competitive universities for limited contingent of applicants, offered by L.A. Serkov, has been simplified up to level, allowing to investigate it by methods of the qualitative theory of dynamic systems. 8 critical points of the simplified dynamic system are defined and the analysis of their stability are made. It has allowed receiving all regimes of education system’s behavio

Theorem about the number and structure of the singular points n-dimensional dynamical system of population dynamics Lotka-Volterra in context of informational analysis and modeling

By elementary methods of combinatorial mathematics and uniqueness of solutions systems of linear algebraic equations for non degenerate cases proved a theorem about the number and structure of the singular points of n-dimensional dynamical system of population a dynamics Lotka-Volterra model. Showed that the number of singular points for this system is equal to 2 and their structure on a combination of zero nand nonzero coordinates coincides with the binomial coefficientsyesBelgorod State Universit

Mathematical Modeling of Training and Dynamics of Scientific Personnel

Qualitative and numerical analysis of mathematical model of training and dynamics of scientific personnel, which is a dynamic system of third order, describing the interaction of scientific personnel without degrees, candidates and doctors of sciences were don

Black Carbon and Particulate Matter Concentrations in Eastern Mediterranean Urban Conditions: An Assessment Based on Integrated Stationary and Mobile Observations

There is a paucity of comprehensive air quality data from urban areas in the Middle East. In this study, portable instrumentation was used to measure size-fractioned aerosol number, mass, and black carbon concentrations in Amman and Zarqa, Jordan. Submicron particle number concentrations at stationary urban background sites in Amman and Zarqa exhibited a characteristic diurnal pattern, with the highest concentrations during traffic rush hours (2–5 × 104 cm−3 in Amman and 2–7 × 104 cm−3 in Zarqa). Super-micron particle number concentrations varied considerably in Amman (1–10 cm−3). Mobile measurements identified spatial variations and local hotspots in aerosol levels within both cities. Walking paths around the University of Jordan campus showed increasing concentrations with proximity to main roads with mean values of 8 × 104 cm−3, 87 µg/m3, 62 µg/m3, and 7.7 µg/m3 for submicron, PM10, PM2.5, and black carbon (BC), respectively. Walking paths in the Amman city center showed moderately high concentrations (mean 105 cm−3, 120 µg/m3, 85 µg/m3, and 8.1 µg/m3 for submicron aerosols, PM10, PM2.5, and black carbon, respectively). Similar levels were found along walking paths in the Zarqa city center. On-road measurements showed high submicron concentrations (>105 cm−3). The lowest submicron concentration

Antiproliferative activity of five garcinia species collected in Sabah, Malaysian Borneo against estrogen receptor-human breast carcinoma (MCF-7) cell line

Garcinia species are well-known for their unique properties of having natural secondary metabolite compounds called xanthone as well as their ethnomedicinal values such as antioxidant, anticancer, anti-inflammatory and antibacterial properties. The study was conducted to investigate the antiproliferative activity of peel, flesh and seed extracts of G. dulcis, G. parvifolia, G. nitida, G. mangostana var. mangosta and G. cambogia collected from Malaysian Borneo (Sabah) against estrogen receptor-positive human breast carcinoma (MCF-7) cells. The antiproliferative activity was assessed using 3-(4,5-dimethylthiazol-2-yl)-2,5- diphenyltetrazolium bromide (MTT) assay. The results showed that G. dulcis seed induced strongest antiproliferative activity against MCF-7 cancer cell line with the IC50 value of 2.5±0.0 μg/ml, followed by G. dulcis flesh, G. mangostana var. mangostana peel and G. dulcis peel with IC50 values of 9.33 ± 3.21, 11.17 ± 1.04 and 17.67 ± 2.08 μg/ml, respectively. Meanwhile, the IC50 value for G. cambogia peel was 56.67 ± 10.5 μg/ml. No IC50 value was detected in all parts of G. parvifolia and G. nitida at concentration tested (<100 μg/ml). Overall, this study clearly showed that the whole fruit of G. dulcis displayed potent cytotoxic effect by inducing antiproliferative activity at low concentration. Further studies are needed in the future to develop this fruit as pharmaceutical and nutraceutical product for the treatment and prevention against cancer

Regional Inhaled Deposited Dose of Urban Aerosols in an Eastern Mediterranean City

We calculated the regional deposited dose of inhaled particulate matter based on number/mass concentrations in Amman, Jordan. The dose rate was the highest during exercising but was generally lower for females compared to males. The fine particles dose rate was 10(10)-10(11) particles/h (10(1)-10(2) mu g/h). The PM10 dose rate was 49-439 mu g/h for males and 36-381 mu g/h for females. While resting, the PM10 deposited in the head airways was 67-77% and 8-12% in the tracheobronchial region. When exercising, the head airways received 37-44% of the PM10, whereas the tracheobronchial region received 31-35%. About 8% (exercise) and 14-16% (rest) of the PM2.5 was received in the head airways, whereas the alveolar received 74-76% (exercise) and 54-62% (rest). Extending the results for common exposure scenarios in the city revealed alarming results for service workers and police officers; they might receive 50 mu g/h PM2.5 and 220 mu g/h PM10 while doing their duty on main roads adjacent to traffic. This is especially critical for a pregnant police officer. Outdoor athletic activities (e.g., jogging along main roads) are associated with high PM2.5 and PM10 dose rates (100 mu g/h and -425 mu g/h, respectively).Peer reviewe

Regional Inhaled Deposited Dose of Urban Aerosols in an Eastern Mediterranean City

We calculated the regional deposited dose of inhaled particulate matter based on number/mass concentrations in Amman, Jordan. The dose rate was the highest during exercising but was generally lower for females compared to males. The fine particles dose rate was 1010–1011 particles/h (101–102 µg/h). The PM10 dose rate was 49–439 µg/h for males and 36–381 µg/h for females. While resting, the PM10 deposited in the head airways was 67–77% and 8–12% in the tracheobronchial region. When exercising, the head airways received 37–44% of the PM10, whereas the tracheobronchial region received 31–35%. About 8% (exercise) and 14–16% (rest) of the PM2.5 was received in the head airways, whereas the alveolar received 74–76% (exercise) and 54–62% (rest). Extending the results for common exposure scenarios in the city revealed alarming results for service workers and police officers; they might receive PM2.5 and 220 µg/h PM10 while doing their duty on main roads adjacent to traffic. This is especially critical for a pregnant police officer. Outdoor athletic activities (e.g., jogging along main roads) are associated with high PM2.5 and PM10 dose rates (100 µg/h and ~425 µg/h, respectively)

Regional Inhaled Deposited Dose of Urban Aerosols in an Eastern Mediterranean City

We calculated the regional deposited dose of inhaled particulate matter based on number/mass concentrations in Amman, Jordan. The dose rate was the highest during exercising but was generally lower for females compared to males. The fine particles dose rate was 1010–1011 particles/h (101–102 µg/h). The PM10 dose rate was 49–439 µg/h for males and 36–381 µg/h for females. While resting, the PM10 deposited in the head airways was 67–77% and 8–12% in the tracheobronchial region. When exercising, the head airways received 37–44% of the PM10, whereas the tracheobronchial region received 31–35%. About 8% (exercise) and 14–16% (rest) of the PM2.5 was received in the head airways, whereas the alveolar received 74–76% (exercise) and 54–62% (rest). Extending the results for common exposure scenarios in the city revealed alarming results for service workers and police officers; they might receive PM2.5 and 220 µg/h PM10 while doing their duty on main roads adjacent to traffic. This is especially critical for a pregnant police officer. Outdoor athletic activities (e.g., jogging along main roads) are associated with high PM2.5 and PM10 dose rates (100 µg/h and ~425 µg/h, respectively)

High frequency magnetic oscillations of the organic metal θ\theta-(ET)4_4ZnBr4_4(C6_6H4_4Cl2_2) in pulsed magnetic field of up to 81 T

De Haas-van Alphen oscillations of the organic metal $\theta$-(ET)$_4$ZnBr$_4$(C$_6$H$_4$Cl$_2$) are studied in pulsed magnetic fields up to 81 T. The long decay time of the pulse allows determining reliable field-dependent amplitudes of Fourier components with frequencies up to several kiloteslas. The Fourier spectrum is in agreement with the model of a linear chain of coupled orbits. In this model, all the observed frequencies are linear combinations of the frequency linked to the basic orbit $\alpha$ and to the magnetic-breakdown orbit $\beta$.Comment: 6 pages, 4 figure

Accessing elite nurses for research: reflections on the theoretical and practical issues of telephone interviewing

Elite groups are interesting as they frequently are powerful (in terms of position, knowledge and influence) and enjoy considerable authority. It is important, therefore, to involve them in research concerned with understanding social contexts and processes. This is particularly pertinent in healthcare, where considerable strategic development and change are features of everyday practice that may be guided or perceived as being guided, by elites. This paper evolved from a study investigating the availability and role of nurses whose remit involved leading nursing research and development within acute NHS Trusts in two health regions in Southern England. The study design included telephone interviews with Directors of Nursing Services during which time the researchers engaged in a reflective analysis of their experiences of conducting research with an `elite' group. Important issues identified were the role of gatekeepers, engagement with elites and the use of the telephone interview method in this context. The paper examines these issues and makes a case for involving executive nurses in further research. The paper also offers strategies to help researchers design and implement telephone interview studies successfully to maximise access to the views and experiences of `hard to reach groups', such as elites, while minimising the associated disruption