64 research outputs found
Color Effects Associated with the 1999 Microlensing Brightness Peaks in Gravitationally Lensed Quasar Q2237+0305
Photometry of the Q2237+0305gravitational lens in VRI spectral bands with the
1.5-m telescope of the high-altitude Maidanak observatory in 1995-2000 is
presented. Monitoring of Q2237+0305 in July-October 2000, made at nearly daily
basis, did not reveal rapid (night-to-night and intranight) variations of
brightness of the components during this time period. Rather slow changes of
magnitudes of the components were observed, such as 0.08 mag fading of B and C
components and 0.05 mag brightening of D in R band during July 23 - October 7,
2000. By good luck three nights in 1999 were almost at the time of the strong
brightness peak of image C, and approximately in the middle of the ascending
slope of the image A brightness peak. The C component was the most blue one in
the system in 1998 and 1999, having changed its (V-I) color from 0.56 mag to
0.12 mag since August 1997, while its brightness increased almost 1.2 mag
during this time period. The A component behaved similarly between August 1998
and August 2000, having become 0.47 mag brighter in R, and at the same time,
0.15 mag bluer. A correlation between the color variations and variations of
magnitudes of the components is demonstrated to be significant and reaches
0.75, with a regression line slope of 0.33. A color (V-I) vrs color (V-R) plot
shows the components settled in a cluster, stretched along a line with a slope
of 1.31. Both slopes are noticeably smaller than those expected if a standard
galactic interstellar reddening law were responsible for the differences
between the colors of images and their variations over time. We attribute the
brightness and color changes to microlensing of the quasar's structure, which
we conclude is more compact at shorter wavelengths, as predicted by most quasar
models featuring an energizing central source.Comment: 14 pages, 7 figures, LaTeX, submitted to A&
К чему приводит неограниченное право на развод?
Article is devoted to changes of the Russian family legislation in the XX century. Laws of the Russian Empire provided very few reasons for divorce. At the end of XIX - the beginning of the XX centuries the part of the intellectuals demanded liberalization of the legislation. The reforms which happened after October revolution of 1917 considerably changed all system of family values that led to strengthening of crisis of a family.Статья посвящена изменениям российского семейного законодательства в ХХ в. Законы Российской империи предусматривали немного причин для развода. В конце ХIХ - начале ХХ вв. часть интеллигенции требовала либерализации законодательства. Реформы, произошедшие после Октябрьской революции 1917 г., радикально изменили всю систему семейных ценностей, что привело к усилению кризиса семьи
Time delays in PG1115+080: new estimates
We report new estimates of the time delays in the quadruple gravitationally
lensed quasar PG1115+080, obtained from the monitoring data in filter R with
the 1.5-m telescope at the Maidanak Mountain (Uzbekistan, Central Asia) in
2004-2006. The time delays are 16.4 days between images C and B, and 12 days
between C and A1+A2, with image C being leading for both pairs. The only known
estimates of the time delays in PG1115 are those based on observations by
Schechter et al. (1997) -- 23.7 and 9.4 days between images C and B, C and
A1+A2, respectively, as calculated by Schechter et al., and 25 and 13.3 days as
revised by Barkana (1997) for the same image components with the use of another
method. The new values of time delays in PG 1115+080 may be expected to provide
larger estimates of the Hubble constant thus decreasing a diversity between the
H_0 estimates taken from gravitationally lensed quasars and with other methods.Comment: 5 pages, 2 figures, Accepted for publication in MNRAS Letter
Recommended from our members
Epidemiology and Forecast of the Prevalence of Esophageal Cancer in the Countries of Central and Eastern Europe
In this article the problems of the prevalence of esophageal cancer and the spatial distribution of mortality rates from this disease are considered using as examples the NUTS 2 regions in six countries of Central and Eastern Europe (Austria, Germany, the Czech Republic, Poland, Slovakia and Hungary). The rates of mortality from esophageal cancer are analyzed by statistical methods and by spatial econometrics. A study is carried out of the features of the spatial distribution of the rates of mortality from esophageal cancer. It allows us to determine more and less epidemiologically affected regions and to carry out more detailed studies on the link between the mortality rates from esophageal cancer and various factors, such as the environmental situation, socio-demographic characteristics of the population, culture and nature of nutrition, the general health status of the population, the availability of resources and the level of healthcare in the region. By means of the multifactor regression model we forecast the rates of mortality from esophageal cancer, taking into account characteristics of the countries, the dynamics of the number of patients with diseases of the esophagus and the general time trend
PG 1115+080: variations of the A2/A1 flux ratio and new values of the time delays
We report the results of our multicolor observations of PG 1115+080 with the
1.5-m telescope of the Maidanak Observatory (Uzbekistan, Central Asia) in
2001-2006. Monitoring data in filter R spanning the 2004, 2005 and 2006 seasons
(76 data points) demonstrate distinct brightness variations of the source
quasar with the total amplitude of almost 0.4 mag. Our R light curves have
shown image C leading B by 16.4d and image (A1+A2) by 12d that is inconsistent
with the previous estimates obtained by Schechter et al. in 1997 - 24.7d
between B and C and 9.4d between (A1+A2) and C. The new values of time delays
in PG 1115+080 must result in larger values for the Hubble constant, thus
reducing difference between its estimates taken from the gravitational lenses
and with other methods. Also, we analyzed variability of the A2/A1 flux ratio,
as well as color changes in the archetypal "fold" lens PG 1115+080. We found
the A1/A2 flux ratio to grow during 2001-2006 and to be larger at longer
wavelengths. In particular, the A2/A1 flux ratio reached 0.85 in filter I in
2006. We also present evidence that both the A1 and A2 images might have
undergone microlensing during 2001-2006, with the descending phase for A1 and
initial phase for A2. We find that the A2/A1 flux ratio anomaly in PG 1115 can
be well explained both by microlensing and by finite distance of the source
quasar from the caustic fold.Comment: 14 pages, 7 figures, 8 tables, Accepted for publication in MNRA
Immediate results of surgical treatment of postinfarction left ventricular aneurysms by restoring the optimal volume and geometry of the left ventricle
The article presents an analysis of surgical remodeling of the left ventricle of the heart in patients with postinfarction aneurysms. The original and traditional methods of plastics are compared. This shows the possibility of preoperative calculation of the final diastolic volume and the formation of a conical, close to natural, form of the left ventricle. The advantages of the original method of plasticity of postinfarction aneurysms are demonstrated.В работе представлен анализ хирургического ремоделирования левого желудочка сердца у больных с постинфарктными аневризмами. Проведено сравнение оригинального и традиционных способов пластики. При этом показаны возможность дооперационного расчета конечного диастолического объема и формирование конической, близкой к естественной, формы левого желудочка. Продемонстрированы преимущества оригинального способа пластики постинфарктных аневризм
Surgical correction of ischemic mitral regurgitation in patients with chronic post-infarction left ventricular aneurysm
Patients with postinfarction left ventricular aneurysm (PLVA) and mitral regurgitation rank among the most serious patient groups whose surgical treatment is associated with high risk. Development of cardiosurgery and significant improvement of surgical outcomes so far have not yet resulted in unambiguous indications and a one-for-all approach to the surgery of PLVA combined with mitral regurgitation. A broad spectrum of surgical modalities is allowed. Based on its own performance practice and capacity, each clinic opts for its own extent of aggressive approach to patient treatment. Development of new and more improved surgical treatment strategies will enable one to come much closer to the finding of optimal ways to correct PLVA with ischemic mitral insufficiency.Больные с постинфарктной аневризмой левого желудочка (ПАЛЖ) и митральной регургитацией составляют одну из наиболее тяжелых групп пациентов, оперативное лечение которых сопряжено с большим риском. развитие кардиохирургии и значительное улучшение результатов операций на сегодняшний день не привело к формированию однозначных показаний и единого подхода к хирургии ПАЛЖ в сочетании с митральной регургитацией. В выборе подходов лечения допускается широкий спектр действий. каждая клиника, основываясь на собственном опыте и возможностях, выбирает степень агрессивности в отношении лечения пациентов. разработка новых, более совершенных методов оперативного лечения позволит в еще большей степени приблизиться к открытию оптимальных способов коррекции ПАЛЖ в сочетании с ишемической недостаточностью МК
Around-the-clock observations of the Q0957+561A,B gravitationally lensed quasar. II. Results for the second observing season
We report on an observing campaign in 2001 March to monitor the brightness of the later arriving Q0957+561B image in order to compare with the previously published brightness observations of the (first-arriving) A image. The 12 participating observatories provided 3543 image frames, which we have analyzed for brightness fluctuations. From our classical methods for time-delay determination, we find a 417.09 ± 0.07 day time delay, which should be free of effects due to incomplete sampling. During the campaign period, the quasar brightness was relatively constant and only small fluctuations were found; we compare the structure function for the new data with structure function estimates for the 1995-1996 epoch and show that the structure function during our observing interval is unusually depressed. We also examine the data for any evidence of correlated fluctuations at zero lag. We discuss the limits of our ability to measure the cosmological time delay if the quasar's emitting surface is time resolved, as seems likely
The Human Serum Metabolome
Continuing improvements in analytical technology along with an increased interest in performing comprehensive, quantitative metabolic profiling, is leading to increased interest pressures within the metabolomics community to develop centralized metabolite reference resources for certain clinically important biofluids, such as cerebrospinal fluid, urine and blood. As part of an ongoing effort to systematically characterize the human metabolome through the Human Metabolome Project, we have undertaken the task of characterizing the human serum metabolome. In doing so, we have combined targeted and non-targeted NMR, GC-MS and LC-MS methods with computer-aided literature mining to identify and quantify a comprehensive, if not absolutely complete, set of metabolites commonly detected and quantified (with today's technology) in the human serum metabolome. Our use of multiple metabolomics platforms and technologies allowed us to substantially enhance the level of metabolome coverage while critically assessing the relative strengths and weaknesses of these platforms or technologies. Tables containing the complete set of 4229 confirmed and highly probable human serum compounds, their concentrations, related literature references and links to their known disease associations are freely available at http://www.serummetabolome.ca
- …