170 research outputs found
Serum level of lactate dehydrogenase, homocystein, hemoglobin and platelet in preeclampsia
Objectives: Pre-eclampsia affects approximately 5-8% of pregnant women. The aim of this study was to compare the serum level of Lactate dehydrogenase (LDH), Homocystein, Hemoglubin and platelet in pregnant women diagnosed as pre-eclampsia and a normal group in Gorgan city, Northeastern Iran from 2007-2008. Methodology: In this case control study, 50 cases of pre-eclampsia were compared with the control group women hospitalized in Dezyani hospital. Pre-eclampsia criteria were: Blood pressure more than or equal to 140/90 mm hg and Proteinuria greater or equal to 300 mg/ 24 hours urine sample in the third trimester. Hemoglobin, platelet, LDH and hemocystein were measured. Data were analyzed by the mean of SPSS-14 program & Chi-2 or t-student were used. Results: The difference of BMI and family incomes was significant between two groups (P-value0.01). Hemocystein level was more than normal range in five patients with pre-eclampsia (P-value<0.001). Conclusions: In this study, hemocystein level was significantly higher in pre-eclampsia patients but LDH, hemoglobin and platelet level had no significant difference
Correlation between the cardiorespiratory endurance, dynamic postural control and thoracic kyphosis angle among the students
Background: Any deviation in the normal spinal alignment can alter the cardiorespiratory endurance and the posture control. The aim of present study was to investigate the correlation between cardiorespiratory endurance, dynamic postural control and kyphosis angle among the students. Materials and Methods: This cross-sectional study was carried out on students (n=100; 48 girls and 52 boys) selected randomly according to inclusion criteria. Cardiorespiratory endurance, postural control and kyphosis angle were assessed using shuttle run test, Y balance test and flexible ruler, respectively. Normal distribution of the data was assessed using the Kolmogorov–Smirnov test. Data were analyzed using Pearson correlation product moment and linear regression (P≤0.05). Results: The results showed a significant negative correlation between the cardiorespiratory endurance and kyphosis angle (P=0.012, r=-0.3.3). In addition, a significant negative correlation was observed between the dynamic postural control and kyphosis angle (P=0.003, r=-0.254). Conclusion: According to our findings it seems mandatory for health and school's, sport coaches to screen the student's spinal deformities and evaluate its associated complications (e.g. decreased cardiorespiratory endurance and postural balance)
Application of STATCOM-SMES Compensator for Power System Dynamic Performance Improvement
The growth of distributed generation within the bulk power system will result in the need for greater control of transmission line power flows. Static Synchronous Compensators (STATCOM) can only exchange reactive power with power grid and is effective for improving voltage stability. The integration of Superconducting Magnetic Energy Storage(SMES) with a STATCOM can extend the traditional STATCOM capabilities to four-quadrant bulk power system power flow control and providing exchange both reactive and active power for STATCOM with the ac network. In this paper presents how a SMES system can be connected to the ac system via the dc bus of a STATCOM. It's shown how the integration of STATCOM and SMES allows bus voltage regulation and power oscillation damping (POD) to be achieved simultaneously. The dynamic performance of the integrated STATCOM-SMES is evaluated through simulation by using PSCAD/EMTDC software and shows the compensation effectiveness of this integrated compensator
Regaining the FORS: optical ground-based transmission spectroscopy of the exoplanet WASP-19b with VLT+FORS2
In the past few years, the study of exoplanets has evolved from being pure
discovery, then being more exploratory in nature and finally becoming very
quantitative. In particular, transmission spectroscopy now allows the study of
exoplanetary atmospheres. Such studies rely heavily on space-based or large
ground-based facilities, because one needs to perform time-resolved, high
signal-to-noise spectroscopy. The very recent exchange of the prisms of the
FORS2 atmospheric diffraction corrector on ESO's Very Large Telescope should
allow us to reach higher data quality than was ever possible before. With
FORS2, we have obtained the first optical ground-based transmission spectrum of
WASP-19b, with 20 nm resolution in the 550--830 nm range. For this planet, the
data set represents the highest resolution transmission spectrum obtained to
date. We detect large deviations from planetary atmospheric models in the
transmission spectrum redwards of 790 nm, indicating either additional sources
of opacity not included in the current atmospheric models for WASP-19b or
additional, unexplored sources of systematics. Nonetheless, this work shows the
new potential of FORS2 for studying the atmospheres of exoplanets in greater
detail than has been possible so far.Comment: 7 pages, 9 figures, 3 tables. Accepted for publication in A&
Validity and Reliability of the Jefferson Scale of Empathy, Nursing Student Version R in a Sample of Iranian Oncology Nurses
Background: Empathy is essential in the process of nurse-patient relationships in oncology wards. The lack of a rigorous tool to
measure empathy in oncology nurses makes the research difficult.
Objectives: Modifying a Persian translation of the Jefferson scale of empathy to create an Iranian version of the Jefferson scale of
empathy-nursing student version R (JSE-NS version R), and to determine its validity and reliability in oncology nurses of Tehran
Universities of Medical Sciences.
Methods: This is a methodological study with cross-sectional design, conducted in 2015. The translation and modification process
was conducted according to the World Health Organization guidelines and an Iranian version of the scale was created. Different
types of validity, including face and content validity together with construct and convergent validity were assessed. Construct validity
was evaluated in a convenience sample of oncology nurses (n = 181) through confirmatory (CFA) and exploratory factor analysis
(EFA). By correlation assessment between the total score of the JSE-NS version R and the subscales of the interpersonal reactivity index
(IRI), convergent validity was tested. Reliability was ascertained by assessing the internal consistency and stability of the scale.
The data were analyzed using SPSS-13 and LISREL 8.8.
Results: Face and content validity of the scale was confirmed by an expert panel. The initial CFA did not show a three-factor structure
of empathy, thus an EFA was run and a four-factor model with a grand factor was extracted. Subsequently, the results of the final
CFA confirmed acceptable goodness of fit indices for the four-factor structure of empathy, and the scale explained 63% of variances
in the data. Convergent validity showed a significant correlation between the total score of the scale and most subscales of the IRI
(P < 0.001). Cronbach’s alpha value (0.86) and the ICC level (0.90) showed satisfactory results in oncology nurses.
Conclusions: The Iranian version of the Jefferson scale of empathy-NS version R is a psychometrically sound instrument, implying
that it is suitable for measurement of empathy in oncology nurses
Probing the atmosphere of a sub-Jovian planet orbiting a cool dwarf
We derive the 0.01 m binned transmission spectrum, between 0.74 and 1.0
m, of WASP-80b from low resolution spectra obtained with the FORS2
instrument attached to ESO's Very Large Telescope. The combination of the fact
that WASP-80 is an active star, together with instrumental and telluric
factors, introduces correlated noise in the observed transit light curves,
which we treat quantitatively using Gaussian Processes. Comparison of our
results together with those from previous studies, to theoretically calculated
models reveals an equilibrium temperature in agreement with the previously
measured value of 825K, and a sub-solar metallicity, as well as an atmosphere
depleted of molecular species with absorption bands in the IR ().
Our transmission spectrum alone shows evidence for additional absorption from
the potassium core and wing, whereby its presence is detected from analysis of
narrow 0.003 m bin light curves (). Further observations with
visible and near-UV filters will be required to expand this spectrum and
provide more in-depth knowledge of the atmosphere. These detections are only
made possible through an instrument-dependent baseline model and a careful
analysis of systematics in the data.Comment: 13 pages, 11 figures, 3 tables. Accepted for publication in MNRA
Dynamic Modeling and Simulation of a STATCOM/SMES Compensator in Power Systems
The advent of Flexible AC Transmission Systems (FACTS) is giving rise to a new family of electronic equipment emerging to controlling and optimizing the performance of power system, e.g. STATCOM. Static synchronous compensator (STATCOM) is one of the most widely used FACTS devices. This paper presents the integration of STATCOM coupled with superconducting magnetic energy storage (SMES) device in order to provide power oscillation damping in power systems. The additional of energy storage allows the combined compensator to exchange both reactive and active power with the ac network and also capability of the STATCOM is enhanced. This paper describes the structure and characteristics of STATCOM/SMES. In addition, using a proper control scheme, STATCOM/SMES is tested on an IEEE 3-bus system and more effective performance of the presented STATCOM/SMES compensator is evaluated with alone STATCOM through the dynamic simulation by using PSCAD/EMTDC software
Dynamic Modeling and Simulation of a STATCOM/SMES Compensator in Power Systems
The advent of Flexible AC Transmission Systems (FACTS) is giving rise to a new family of electronic equipment emerging to controlling and optimizing the performance of power system, e.g. STATCOM. Static synchronous compensator (STATCOM) is one of the most widely used FACTS devices. This paper presents the integration of STATCOM coupled with superconducting magnetic energy storage (SMES) device in order to provide power oscillation damping in power systems. The additional of energy storage allows the combined compensator to exchange both reactive and active power with the ac network and also capability of the STATCOM is enhanced. This paper describes the structure and characteristics of STATCOM/SMES. In addition, using a proper control scheme, STATCOM/SMES is tested on an IEEE 3-bus system and more effective performance of the presented STATCOM/SMES compensator is evaluated with alone STATCOM through the dynamic simulation by using PSCAD/EMTDC software
The Role of Nitrogen in Inducing Salt Stress Tolerance in Crocus sativus L.: Assessment Based on Plant Growth and Ions Distribution in Leaves
Making FORS2 fit for exoplanet observations (again)
For about three years, it was known that precision spectrophotometry with
FORS2 suffered from systematic errors that made quantitative observations of
planetary transits impossible. We identified the Longitudinal Atmospheric
Dispersion Compensator (LADC) as the most likely culprit, and therefore engaged
in a project to exchange the LADC prisms with the uncoated ones from FORS1.
This led to a significant improvement in the depth of FORS2 zero points, a
reduction in the systematic noise, and should make FORS2 again competitive for
transmission spectroscopy of exoplanets.Comment: To appear in the March issue of the ESO Messenge
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