160 research outputs found
Climate change, in the framework of the Constructal Law
Here we present a simple and transparent alternative to the complex models
of earthβs thermal behaviour under time-changing conditions. We show the one-to-one relationship between changes in atmospheric properties and time-dependent changes in temperature and its distribution on earth. The model accounts for convection and radiation, thermal inertia and changes in albedo (Ο) and greenhouse factor (Ξ³). The
constructal law is used as the principle that governs the evolution of fl ow confi guration on earth. The model showed that for two time-dependent scenarios, (Ξ΄Ο = 0.002;
δγ = 0.011) and (Ξ΄Ο = 0.002; δγ = 0.005) the predicted equatorial and polar temperature
increases and the time scales are (ΞTH = 1.16 K; ΞTL = 1.11 K; 104 years) and (0.41 K;0.41 K; 57 years), respectively. A continuous model of temperature variation was used to predict the thermal response of the Earthβs surface to changes bounded by Ξ΄Ο = δγ and Ξ΄Ο = βδγ. The poleward heat current reaches its maximum in the vicinity of 35Β° latitude,accounting for the position of the Ferrel cell between the Hadley and Polar Cells
Finite element 3-D model of a double quantum ring: effects of electric and laser fields on the interband transition
In this work, the changes in the energy of electrons and holes, oscillator
strength and interband transition time when external fields are applied to a
GaAs/AlGaAs semiconductor double ring grown by the droplet epitaxy technique
are theoretically analyzed. We consider a static electric field and an intense
laser field nonresonant with the quantum structure, with variable intensities
and orientations with respect to the symmetry axis of the quantum ring. In the
formalism of the effective mass approximation for electrons and holes, the
energies and wavefunctions were numerically computed using the finite element
method implemented with an accurate three-dimensional model of the real quantum
ring. Laser dressing of the confining potential was performed using the exact
integration formula at each point. Our results show major differences between
the effects of the two types of applied fields, caused mainly by the static
electric-field-induced strong polarizability of the confined electron-hole
pair. In addition, the effects of both fields exhibit strong anisotropy in the
electronic properties as a result of the particular flattened geometry of the
quantum ring. Proper combinations of field strengths and orientations are
helpful in designing accurate tools for the sensitive manipulation of interband
radiative properties.Comment: 23 pages, 15 figures, 3 table
ΠΠ΅ΡΠΎΠ΄Ρ ΠΏΡΠ΅Π½Π°ΡΠ°Π»ΡΠ½ΠΎΠΉ Π΄ΠΈΠ°Π³Π½ΠΎΡΡΠΈΠΊΠΈ: QF-PCR, ΠΠ°ΡΠΈΠΎΡΠΈΠΏ, FISH, NIFTY
Centrul Medical βRepromedβContemporary cytogenetic and molecular genetic technologies offer a solid basis for an accurate and early diagnosis of genetic diseases. Because of the rapid progress in both areas, the prenatal diagnosis became an efficient instrument both for medical geneticists and gynecologists. The development of complex techniques of prenatal molecular diagnosis has produced a real burst of information, which
requires an appropriate interpretation and application by the clinician for the benefit of the patient. Our purpose is to make a brief analysis of the classical and newest methods of prenatal genetic diagnosis and to evaluate the risks and benefits of each method both for pregnant and fetus.Π‘ΠΎΠ²ΡΠ΅ΠΌΠ΅Π½Π½Π°Ρ ΡΠΈΡΠΎΠ³Π΅Π½Π΅ΡΠΈΠΊΠ° ΡΠΎΠ²ΠΌΠ΅ΡΡΠ½ΠΎ Ρ ΠΏΡΠΎΠ³ΡΠ΅ΡΡΠΎΠΌ ΠΌΠΎΠ»Π΅ΠΊΡΠ»ΡΡΠ½ΠΎ-Π³Π΅Π½Π΅ΡΠΈΡΠ΅ΡΠΊΠΈΡ
ΡΠ΅Ρ
Π½ΠΎΠ»ΠΎΠ³ΠΈΠΉ ΠΏΡΠΎΠ»ΠΎΠΆΠΈΠ»ΠΈ ΠΏΡΡΡ ΠΊ Π±ΠΎΠ»Π΅Π΅ ΡΠΎΡΠ½ΠΎΠΌΡ ΠΈ Π·Π½Π°ΡΠΈΡΠ΅Π»ΡΠ½ΠΎ Π±ΠΎΠ»Π΅Π΅ ΡΠ°Π½Π½Π΅ΠΌΡ Π΄ΠΈΠ°Π³Π½ΠΎΡΡΠΈΡΠΎΠ²Π°Π½ΠΈΡ Π³Π΅Π½Π΅ΡΠΈΡΠ΅ΡΠΊΠΈΡ
Π·Π°Π±ΠΎΠ»Π΅Π²Π°Π½ΠΈΠΉ, ΠΊΠΎΡΠΎΡΡΠ΅ ΡΠ΄Π΅Π»Π°Π»ΠΈ ΠΏΡΠ΅Π½Π°ΡΠ°Π»ΡΠ½ΡΡ Π΄ΠΈΠ°Π³Π½ΠΎΡΡΠΈΠΊΡ Π²Π΅ΡΡΠΌΠ° ΡΡΡΠ΅ΠΊΡΠΈΠ²Π½ΡΠΌ ΠΈΠ½ΡΡΡΡΠΌΠ΅Π½ΡΠΎΠΌ Π΄Π»Ρ Π²ΡΠ°ΡΠ° Π³ΠΈΠ½Π΅ΠΊΠΎΠ»ΠΎΠ³Π° ΠΈ Π³Π΅Π½Π΅ΡΠΈΠΊΠ°.
Π Π°Π·ΡΠ°Π±ΠΎΡΠΊΠ° Π±ΠΎΠ»Π΅Π΅ ΡΠ»ΠΎΠΆΠ½ΡΡ
ΠΌΠΎΠ»Π΅ΠΊΡΠ»ΡΡΠ½ΡΡ
ΠΌΠ΅ΡΠΎΠ΄ΠΎΠ² ΠΏΡΠ΅Π½Π°ΡΠ°Π»ΡΠ½ΠΎΠΉ Π΄ΠΈΠ°Π³Π½ΠΎΡΡΠΈΠΊΠΈ ΠΏΡΠΈΠ²Π΅Π»Π° ΠΊ Π²Π·ΡΡΠ²Ρ ΠΈΠ½ΡΠΎΡΠΌΠ°ΡΠΈΠΈ, ΠΊΠΎΡΠΎΡΠ°Ρ Π΄ΠΎΠ»ΠΆΠ½Π° Π±ΡΡΡ ΠΏΡΠΈΠΌΠ΅Π½Π΅Π½Π° Π²ΡΠ°ΡΠ°ΠΌΠΈ Π΄Π»Ρ Π±Π»Π°Π³Π° ΠΏΠ°ΡΠΈΠ΅Π½ΡΠΎΠ². Π‘ ΠΏΠΎΠΌΠΎΡΡΡ ΡΡΠΎΠΉ ΡΡΠ°ΡΡΠΈ ΠΌΡ Ρ
ΠΎΡΠΈΠΌ ΡΠ΄Π΅Π»Π°ΡΡ ΠΊΡΠ°ΡΠΊΠΈΠΉ Π°Π½Π°Π»ΠΈΠ· ΠΊΠ»Π°ΡΡΠΈΡΠ΅ΡΠΊΠΈΡ
ΠΈ Π½ΠΎΠ²Π΅ΠΉΡΠΈΡ
ΠΌΠ΅ΡΠΎΠ΄ΠΎΠ² Π΄Π»Ρ ΠΏΡΠ΅Π½Π°ΡΠ°Π»ΡΠ½ΠΎΠΉ Π΄ΠΈΠ°Π³Π½ΠΎΡΡΠΈΠΊΠΈ Π³Π΅Π½Π΅ΡΠΈΡΠ΅ΡΠΊΠΈΡ
Π·Π°Π±ΠΎΠ»Π΅Π²Π°Π½ΠΈΠΉ,
Π²Π·Π²Π΅ΡΠΈΡΡ ΠΏΠΎΠ»ΡΠ·Ρ ΠΈ ΡΠΈΡΠΊ ΠΊΠ°ΠΆΠ΄ΠΎΠ³ΠΎ ΠΌΠ΅ΡΠΎΠ΄Π° ΠΊΠ°ΠΊ Π΄Π»Ρ Π±Π΅ΡΠ΅ΠΌΠ΅Π½Π½ΠΎΠΉ, ΡΠ°ΠΊ ΠΈ Π΄Π»Ρ ΠΏΠ»ΠΎΠ΄Π°
ΠΠ΅ΡΠΎΠ΄Ρ ΠΏΡΠ΅Π½Π°ΡΠ°Π»ΡΠ½ΠΎΠ³ΠΎ Π³Π΅Π½Π΅ΡΠΈΡΠ΅ΡΠΊΠΎΠ³ΠΎ ΡΠΊΡΠΈΠ½ΠΈΠ½Π³Π°. ΠΠ²ΠΎΠΉΠ½ΠΎΠΉ, ΡΡΠΎΠΉΠ½ΠΎΠΉ ΠΈ ΡΠ΅ΡΠ²Π΅ΡΠ½ΠΎΠΉ ΡΠ΅ΡΡΡ
Centrul Medical βRepromedβAntenatal screening of hereditary diseases and congenital malformations during the first and second trimester of
pregnancy is an important tool for the evaluation of the intrauterine fetal condition. Special attention is paid to the principles of antenatal screening organization, echographic markers, and biochemical methods of fetal development assessment. Antenatal genetic screening includes fetal ultrasound and biochemical screening (estimation of certain plasmatic markers, which fluctuate in cases of certain fetal diseases).
There are several types of screening (depending on the number of performed biochemical tests): double test (combined test), triple test, and quadruple test. Screening tests are not pretending to be the source of the final diagnosis. They rather give a possibility to identify the group of pregnant with an increased risk of certain fetal pathologies, which require specific diagnostic methods. The current recommendations are presented for general practitioners, gynecologists, specialists in genetics, and patients.ΠΡΠ΅Π½Π°ΡΠ°Π»ΡΠ½ΡΠΉ ΡΠΊΡΠΈΠ½ΠΈΠ½Π³ Π½Π°ΡΠ»Π΅Π΄ΡΡΠ²Π΅Π½Π½ΡΡ
ΠΈ Π²ΡΠΎΠΆΠ΄Π΅Π½Π½ΡΡ
Π·Π°Π±ΠΎΠ»Π΅Π²Π°Π½ΠΈΠΉ Π² ΠΏΠ΅ΡΠ²ΠΎΠΌ ΠΈ Π²ΡΠΎΡΠΎΠΌ ΡΡΠΈΠΌΠ΅ΡΡΡΠ΅ Π±Π΅ΡΠ΅ΠΌΠ΅Π½Π½ΠΎΡΡΠΈ ΡΠΏΠΎΡΠΎΠ±ΡΡΠ²ΡΠ΅Ρ ΠΏΠΎΠ»ΡΡΠ΅Π½ΠΈΡ Π΄ΠΎΠΏΠΎΠ»Π½ΠΈΡΠ΅Π»ΡΠ½ΠΎΠΉ ΠΈΠ½ΡΠΎΡΠΌΠ°ΡΠΈΠΈ ΠΎΡΠ½ΠΎΡΠΈΡΠ΅Π»ΡΠ½ΠΎ Π·Π΄ΠΎΡΠΎΠ²ΡΡ ΠΏΠ»ΠΎΠ΄Π°. ΠΡΠΎΠ±ΠΎΠ΅ Π²Π½ΠΈΠΌΠ°Π½ΠΈΠ΅ ΡΠ΄Π΅Π»Π΅Π½ΠΎ ΠΏΡΠΈΠ½ΡΠΈΠΏΠ°ΠΌ ΠΎΡΠ³Π°Π½ΠΈΠ·Π°ΡΠΈΠΈ ΠΏΡΠ΅Π½Π°ΡΠ°Π»ΡΠ½ΠΎΠ³ΠΎ ΡΠΊΡΠΈΠ½ΠΈΠ½Π³Π°, ΡΠ»ΡΡΡΠ°Π·Π²ΡΠΊΠΎΠ²ΡΠΌ ΠΌΠ°ΡΠΊΠ΅ΡΠ°ΠΌ ΠΈ Π±ΠΈΠΎΡ
ΠΈΠΌΠΈΡΠ΅ΡΠΊΠΈΠΌ ΠΌΠ΅ΡΠΎΠ΄Π°ΠΌ Π΄ΠΈΠ°Π³Π½ΠΎΡΡΠΈΠΊΠΈ ΡΠ°Π·Π²ΠΈΡΠΈΡ ΠΏΠ»ΠΎΠ΄Π°. ΠΡΠ΅Π½Π°ΡΠ°Π»ΡΠ½ΡΠΉ Π³Π΅Π½Π΅ΡΠΈΡΠ΅ΡΠΊΠΈΠΉ ΡΠΊΡΠΈΠ½ΠΈΠ½Π³ Π²ΠΊΠ»ΡΡΠ°Π΅Ρ Π² ΡΠ΅Π±Ρ ΡΠ»ΡΡΡΠ°Π·Π²ΡΠΊΠΎΠ²ΠΎΠΉ ΠΈ Π±ΠΈΠΎΡ
ΠΈΠΌΠΈΡΠ΅ΡΠΊΠΈΠΉ ΡΠΊΡΠΈΠ½ΠΈΠ½Π³, ΡΠΎ Π΅ΡΡΡ ΠΎΠΏΡΠ΅Π΄Π΅Π»Π΅Π½ΠΈΠ΅ ΡΠ΅ΡΠΎΠ»ΠΎΠ³ΠΈΡΠ΅ΡΠΊΠΈΡ
ΠΌΠ°ΡΠΊΠ΅ΡΠΎΠ², ΠΈΠ·ΠΌΠ΅Π½ΡΡΡΠΈΡ
ΡΡ ΠΏΡΠΈ Π½Π΅ΠΊΠΎΡΠΎΡΡΡ
ΠΏΠ°ΡΠΎΠ»ΠΎΠ³ΠΈΡΡ
. ΠΡΡΡ Π½Π΅ΡΠΊΠΎΠ»ΡΠΊΠΎ ΡΠΈΠΏΠΎΠ² ΡΠΊΡΠΈΠ½ΠΈΠ½Π³Π°: Π΄Π²ΠΎΠΉΠ½ΠΎΠΉ ΡΠ΅ΡΡ (ΠΊΠΎΠΌΠ±ΠΈΠ½ΠΈΡΠΎΠ²Π°Π½Π½ΡΠΉ ΡΠ΅ΡΡ), ΡΡΠΎΠΉΠ½ΠΎΠΉ ΡΠ΅ΡΡ ΠΈ ΡΠ΅ΡΠ²Π΅ΡΠ½ΠΎΠΉ
ΡΠ΅ΡΡ β Π² Π·Π°Π²ΠΈΡΠΈΠΌΠΎΡΡΠΈ ΠΎΡ ΠΊΠΎΠ»ΠΈΡΠ΅ΡΡΠ²Π° Π±ΠΈΠΎΡ
ΠΈΠΌΠΈΡΠ΅ΡΠΊΠΈΡ
ΠΏΠΎΠΊΠ°Π·Π°ΡΠ΅Π»Π΅ΠΉ.
Π‘ΠΊΡΠΈΠ½ΠΈΠ½Π³ΠΎΠ²ΡΠ΅ ΡΠ΅ΡΡΡ ΠΏΡΠ΅Π΄Π½Π°Π·Π½Π°ΡΠ΅Π½Ρ Π½Π΅ Π΄Π»Ρ ΠΎΠΊΠΎΠ½ΡΠ°ΡΠ΅Π»ΡΠ½ΠΎΠ³ΠΎ Π΄ΠΈΠ°Π³Π½ΠΎΠ·Π°, Π° Π΄Π»Ρ Π²ΡΡΠ²Π»Π΅Π½ΠΈΡ Π±Π΅ΡΠ΅ΠΌΠ΅Π½Π½ΡΡ
ΠΆΠ΅Π½ΡΠΈΠ½, ΠΈΠΌΠ΅ΡΡΠΈΡ
Π²ΡΡΠΎΠΊΠΈΠΉ ΡΠΈΡΠΊ ΠΏΡΠΈ Π½Π΅ΠΊΠΎΡΠΎΡΡΡ
ΠΏΠ°ΡΠΎΠ»ΠΎΠ³ΠΈΡΡ
ΠΏΠ»ΠΎΠ΄Π°, ΠΊΠΎΡΠΎΡΡΠΌ ΡΠ΅ΠΊΠΎΠΌΠ΅Π½Π΄ΡΠ΅ΡΡΡ Π΄ΠΈΠ°Π³Π½ΠΎΡΡΠΈΡΠ΅ΡΠΊΠΈΠ΅ ΠΈΡΡΠ»Π΅Π΄ΠΎΠ²Π°Π½ΠΈΡ. Π‘ΡΠ°ΡΡΡ ΡΠΎΠ΄Π΅ΡΠΆΠΈΡ ΡΠ΅ΠΊΠΎΠΌΠ΅Π½Π΄Π°ΡΠΈΠΈ ΠΊΠ°ΠΊ Π΄Π»Ρ ΡΠ΅ΠΌΠ΅ΠΉΠ½ΡΡ
Π²ΡΠ°ΡΠ΅ΠΉ, Π³ΠΈΠ½Π΅ΠΊΠΎΠ»ΠΎΠ³ΠΎΠ² ΠΈ Π³Π΅Π½Π΅ΡΠΈΠΊΠΎΠ², ΡΠ°ΠΊ ΠΈ Π΄Π»Ρ ΠΏΠ°ΡΠΈΠ΅Π½ΡΠΎΠ²
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