•Two different real time simulators designs were presented and compared in the paper.•Both designs are based on the Simulink and on the real time Linux.•First design is using DAQ cards as the I/O ...interface.•Second design is using IEC61850-based Ethernet communication as the I/O interface.•Both designs provide cheaper alternative for the commercial solutions.
Hardware-in-the-loop simulations might be considered as the most advanced method of power system protection testing. However, availability of these devices remains significantly low due to the cost barrier and sizes of the simulator. A rapid growth of the Matlab/Simulink tools and IEC61850 open source libraries in recent years has opened the possibilities of designing proprietary real time simulators that are comparable with commercial solutions. This paper presents two simulator designs - one based on DAQ cards and the second one based on IEC61850 services. The performance limits of the simulators in the real time were compared in this paper. Furthermore, it was proven that the performance of these simulators is sufficient to conduct successful tests of protection relays. Consequently, the examples of protection relays testing results were discussed. Finally, it was explained why the presented designs might substantially support new protection algorithms verification. It is due to the high availability and the reduced device size.
Childhood education programmes aiming at incorporating topics related to
science, technology, engineering, and mathematics (STEM) have gained
recognition as key levers in the progress of education ...for all students.
Inspiring young people to take part in the discovery and delivery of science
is of paramount importance not only for their well-being but also for their
future human development. To address this need, an outreach model entitled
OH-Kids was designed to empower pupils through the development of high-quality STEM
learning experiences based on a research project. The model is an
opportunity for primary school learners to meet geoscientists while
receiving the take-home message that anyone can get involved in scientific
activities. The effort is part of a research project aimed at the real-time
monitoring of precipitation in Mexico City, which is a smart solution to
rainfall monitoring using information and communications technologies. The
argument behind this effort is that in order to produce the next generation
of problem-solvers, education should ensure that learners develop an
appreciation and working familiarity with a real-world project. Results show
success at introducing the role of researchers and STEM topics to
6–12-year-old learners.
Thyroid hormones (T
3
, T
4
) are well known modulators of different cellular signals including the sphingomyelin pathway. However, studies regarding downstream effects of T
3
on sphingolipid ...metabolism in skeletal muscle are scarce. In the present work we sought to investigate the effects of hyperthyroidism on the activity of the key enzymes of ceramide metabolism as well as the content of fundamental sphingolipids. Based on fiber/metabolic differences, we chose three different skeletal muscles, with diverse fiber compositions: soleus (slow-twitch oxidative), red (fast-twitch oxidative-glycolytic) and white (fast-twitch glycolytic) section of gastrocnemius. We demonstrated that T
3
induced accumulation of sphinganine, ceramide, sphingosine, as well as sphingomyelin, mostly in soleus and in red, but not white section of gastrocnemius. Concomitantly, the activity of serine palmitoyltransferase and acid/neutral ceramidase was increased in more oxidative muscles. In conclusion, hyperthyroidism induced fiber specific changes in the content of sphingolipids that were relatively more related to de novo synthesis of ceramide rather than to its generation via hydrolysis of sphingomyelin.
Abstract Background Ovarian serous cystadenomas are rare in children. No case of recurrence after surgical resection in a premenarchal girl has been published. Case An 8-year-old presented with ...abdominal pain and ultrasound showed bilateral ovarian cystic masses with normal clinical and laboratory exam. Cystectomies were performed revealing serous cystadenomas. Ten months later, her pain returned and ultrasound showed new cysts. Persistence of cysts and symptoms required repeat surgery with the same pathology. Summary and conclusion Premenarchal girls with ovarian cystic masses require surgical intervention in cases of persistent symptoms, uncertain diagnosis, or concern for ovarian torsion. With reassuring imaging and tumor markers, conservation of the ovary can be achieved with cystectomy alone. Ultrasound follow-up is recommended after surgical resection until bimanual exam can be performed.
The aim of the study was to evaluate the nitrogen removal and its effects on the plant's growth and leaves morphology. using two subsurface vertical flow (VF bed), with different depths (0.24 m
2
× ...0.70 m; 0.24 m
2
× 0.35 m) and nitrogen load increments. The VF bed were planted with Vetiveria zizanioides, filled with light expanded clay aggregates (Leca®NR 10/20) and fed in parallel mode with synthetic wastewater. High ammonium nitrogen concentration (NH
4
+
-N from 68 ± 3 to 290 ± 8 mg L
−1
) was used without toxicity symptoms in plants, although the effects of ammonium nitrogen load were stopped the growth of the plants. Significant differences between ammonium nitrogen removed in each VF bed obtained for total nitrogen (TN
infl
.) ≥ 27 ± 0.8 g m
−2
d
−1
. The nitrification was contributed to ammonium nitrogen removal because was found higher values of nitrate and nitrite in the effluent. These values were more higher in VF bed 1 than in the VF bed 2, since ammonium nitrogen removal were also more higher in VF bed 1 than in the VF bed 2. Total nitrogen mass balance was carried out and the results show that the nitrification/denitrification process occurred with nitrogen plants uptake. It was observed that the VF bed depth has an influence on all nitrogen removal processes. As higher the depth root system it is seemed to favour the creation of zones with different oxidations conditions that allow the nitrogen compounds to be removed intensively.
A sum rule of superconvergence type for parity violating amplitudes (p.v. analogue of the Gerasimov-Drell-Hearn sum rule) is discussed. The parity violating polarized photon-induced processes for the ...proton target are considered in the framework of effective low energy theories and phenomenological models based on p.v. nucleon-meson effective interactions. It is argued that the verification of the sum rule in future high intensity polarized photon beam experiments is feasible.
Dissolution of guanine in neutral solutions was obscured by peculiar behavior of guanine, indicating an apparent dependence of solubility on the amount of solid guanine used. Here, we demonstrate ...that the problem is caused by the formation of tiny guanine nanoparticles that tend to grow forming stable particles of ca. 800 nm size. This effect can be minimalized by using small quantities of guanine powder for dissolution. We also show that assuming a constant, independent of pH, concentration of neutral form of guanine, at 25 °C equal 25.4 μM, and applying known p K
values related to its dissociation or protonation, it is possible to calculate the concentrations of all conjugate acids and bases of guanine at the given pH value, and by summing them up, the guanine solubility.
Measurements of the longitudinal spin cross section asymmetry for deep inelastic muonnucleon interactions with two high transverse momentum hadrons (
p
T
>
0.7
GeV
) in the final state are presented ...for SMC data for polarized proton and deuteron and for data on polarized deuteron from COMPASS taken in 2002 and 2003. The muon asymmetries determined with a cut on
Q
2
>
1
GeV
2
in SMC are:
A
p
=
0.03
±
0.057
±
0.01
and
A
d
=
0.070
±
0.076
±
0.010
, respectively. From these values a gluon polarization
Δ
G
/
G
=
−
0.20
±
0.28
±
0.10
was obtained at an average fraction of nucleon momentum carried by gluons
η
=
0.07
. The measured asymmetry (with cut on
Q
2
>
1
GeV
2
) in COMPASS is
(
A
d
/
D
)
=
−
0.015
±
0.08
±
0.013
where D is depolarization factor and the gluon polarization
Δ
G
/
G
=
0.06
±
0.31
±
0.06
was obtained at
η
=
0.13
±
0.08
.
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